JP2006119599A - Method of manufacturing optical film, apparatus of manufacturing the same, optical film, polarizing sheet and image display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing an antireflection film having satisfactory antireflection performance and moreover excellent scratch resistance, to provide an antireflection film obtained by the manufacturing method and further to provide a polarizing sheet and an image display device provided with the antireflection film. <P>SOLUTION: In the method of manufacturing the antireflection film having an antireflection layer made of at least one layer on a transparent substrate, at least one layer on the transparent substrate is formed according to a layer forming method comprising the following processes (1) and (2). In the process (1), a coated layer is applied on the transparent substrate and, in the process (2), the coated layer is cured by being irradiated with ionizing radiation in the environment of oxygen concentration lower than that in the air. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a manufacturing method and manufacturing apparatus for an optical film excellent in scratch resistance (particularly, an antireflection film having low reflectance and excellent scratch resistance), and an optical film obtained by the manufacturing method. Furthermore, it is related with the polarizing plate and image display apparatus which comprised this optical film.

  In display devices such as cathode ray tube display (CRT), plasma display (PDP) electroluminescence display (ELD) and liquid crystal display (LCD), protective films for polarizing plates, retardation plates, reflectors, viewing angle widening films Various functional optical films such as an optical compensation film, an antiglare film, a brightness enhancement film, a color correction filter, a color separation film, an ultraviolet or infrared cut film, an antistatic film, and an antireflection film are used. When these films are damaged during production or after being manufactured, they are recognized as image defects, so that strong abrasion resistance is required.

  Among the above, the antireflection film is generally used for a display device such as a cathode ray tube display (CRT), a plasma display (PDP), an electroluminescence display (ELD), and a liquid crystal display (LCD) to reduce contrast due to reflection of external light. In order to prevent reflection of images and images, it is arranged on the outermost surface of the display so as to reduce the reflectance by using the principle of optical interference. For this reason, the establishment of scratches is high, and imparting excellent abrasion resistance was an important issue.

  Such an antireflection film forms a low refractive index layer with an appropriate film thickness on the outermost surface, and optionally a high refractive index layer, a medium refractive index layer, a hard coat layer, etc. between the support (base material). It can produce by doing. In order to realize a low reflectance, a material having a refractive index as low as possible is desired for the low refractive index layer. Further, since the antireflection film is used on the outermost surface of the display, high scratch resistance is required. In order to realize high scratch resistance in a thin film having a thickness of around 100 nm, the strength of the coating itself and the adhesion to the lower layer are required.

  In order to lower the refractive index of the material, there are means of introducing fluorine atoms and lowering the density (introducing voids), but both are in the direction that the film strength and adhesion are impaired and the scratch resistance is lowered, and low It has been difficult to achieve both refractive index and high scratch resistance.

  Patent Documents 1 to 3 describe means for reducing the coefficient of friction on the surface of the film by introducing a polysiloxane structure into the fluorine-containing polymer and improving the scratch resistance. This means is effective to some extent for improving the scratch resistance, but sufficient scratch resistance cannot be obtained only by this method for a film having insufficient essential film strength and interfacial adhesion.

On the other hand, Patent Document 4 describes that the hardness is increased by curing a photocurable resin at a low oxygen concentration. However, in order to efficiently produce an antireflection film with a web (also referred to as a web), there is a limit to the concentration at which nitrogen can be replaced, and satisfactory hardness cannot be obtained.
Patent Documents 5 to 10 describe specific means for nitrogen substitution, but in order to reduce the oxygen concentration until a thin film such as a low refractive index layer is sufficiently cured, a large amount of nitrogen is used. There is a problem that it is necessary and the manufacturing cost increases.
Patent Document 11 describes a method of irradiating ionizing radiation by wrapping around the surface of a hot roll, which is also insufficient to sufficiently cure a special thin film such as a low refractive index layer. .

  Patent Documents 12 and 13 describe increasing the curing sensitivity of the color filter composition by using an oxime compound as the radical polymerization initiator. It was not possible to cure to a sufficient hardness for curing a thin film.

On the other hand, the dip coating method, the micro gravure method, the reverse roll coating method, and the like have been mainly used as the coating method when manufacturing an optical film, particularly an antireflection film. In the dip coating method, vibration of the coating liquid in the liquid receiving tank is inevitable, and stepped unevenness is likely to occur. In the reverse roll coating method and the micro gravure method, stepped unevenness is likely to occur due to roll eccentricity and deflection related to coating. Furthermore, in the microgravure method, coating amount unevenness is likely to occur due to the manufacturing accuracy of the gravure roll and the change with time of the roll and blade due to the contact between the blade and the gravure roll. Further, since these coating methods are post-measuring methods, it is relatively difficult to ensure a stable film thickness. As a pre-measuring method, a method of applying an antireflection film by a die coating method has been proposed. Unevenness occurred remarkably and it was difficult to maintain film thickness stability.
The film thickness unevenness of the antireflection layer is visually detected as color unevenness when applied to an image display device, which is a big problem that impairs quality, and this stabilization has been desired.
JP-A-11-189621 Japanese Patent Laid-Open No. 11-228631 JP 2000-313709 A JP 2002-156508 A JP 11-268240 A Japanese Patent Laid-Open No. 60-90762 JP 59-112870 JP-A-4-301456 Japanese Patent Laid-Open No. 3-67697 JP 2003-300215 A Japanese Patent Publication No. 7-51641 JP 2000-80068 A JP 2001-264530 A

An object of the present invention is to provide a stable production method of an optical film having improved scratch resistance and an optical film obtained by the method.
Another object of the present invention is to provide a stable method for producing an antireflection film having improved anti-scratch properties while having sufficient antireflection ability, and an antireflection film obtained by the method.
Furthermore, in addition to the above, a stable manufacturing method of an optical film (particularly an antireflection film) capable of giving a high-quality image display device while suppressing color unevenness due to the coating process, and an optical film obtained by the method Is to provide.
Another object of the present invention is to provide a polarizing plate and an image display device having such a reflective film.

As a result of intensive studies, the present inventors have found that the above object of the present invention is achieved by the following method for producing an antireflection film, the antireflection film obtained by the method, a polarizing plate, and an image display device. .
[1] A method for producing an optical film having a functional layer comprising at least one layer on a transparent substrate, wherein at least one layer laminated on the transparent substrate is subjected to the following steps (1) and (2): A method for producing an optical film, comprising: forming a layer by a layer forming method. (Layer formation method (I))
(1) A step of coating an application layer on a transparent substrate,
(2) By irradiating ionizing radiation in an oxygen concentration atmosphere lower than the oxygen concentration in the atmosphere,
A step of curing the coating layer.
[2] A method for producing an optical film having a functional layer comprising at least one layer on a transparent substrate, wherein at least one layer laminated on the transparent substrate is subjected to the following steps (1) to (3): The method for producing an optical film as described in the above item [1], further comprising: a layer forming method in which a transporting step (2) and a curing step (3) below are continuously performed.
(1) A step of coating an application layer on a transparent substrate,
(2) A step of transporting the film having the coating layer in an oxygen concentration atmosphere lower than the oxygen concentration in the air,
(3) A step of irradiating the film with ionizing radiation in an atmosphere having an oxygen concentration of 3% by volume or less to cure the coating layer.
[3] A method for producing an optical film having a functional layer comprising at least one layer on a transparent substrate, wherein at least one of the layers laminated on the transparent substrate is subjected to the following (1) to (3): The method for producing an optical film as described in the above [1], comprising a step of forming a layer and a layer forming method in which the following transport step (2) and curing step (3) are continuously performed.
(1) A step of coating an application layer on a transparent substrate,
(2) A step of transporting the film having the coating layer in an oxygen concentration atmosphere lower than the oxygen concentration in the air,
(3) A step of curing the coating layer by irradiating the film with ionizing radiation while heating the film so that the film surface temperature is 25 ° C. or higher in an atmosphere having an oxygen concentration of 3% by volume or less.
[4] A method for producing an optical film having a functional layer comprising at least one layer on a transparent substrate, wherein at least one layer laminated on the transparent substrate is subjected to the following steps (1) to (3): The method for producing an optical film as described in the above item [1], further comprising: a layer forming method in which a transporting step (2) and a curing step (3) below are continuously performed.
(1) A step of coating an application layer on a transparent substrate,
(2) A step of conveying the film having the coating layer in an oxygen concentration atmosphere lower than the oxygen concentration in the atmosphere while heating the film surface temperature to be 25 ° C. or higher,
(3) A step of irradiating the film with ionizing radiation in an atmosphere having an oxygen concentration of 3% by volume or less to cure the coating layer.
[5] A method for producing an optical film having a functional layer comprising at least one layer on a transparent substrate, wherein at least one layer laminated on the transparent substrate is subjected to the following steps (1) to (3): The method for producing an optical film as described in the above item [1], further comprising: a layer forming method in which a transporting step (2) and a curing step (3) below are continuously performed.
(1) A step of coating an application layer on a transparent substrate,
(2) A step of conveying the film having the coating layer in an oxygen concentration atmosphere lower than the oxygen concentration in the atmosphere while heating the film surface temperature to be 25 ° C. or higher,
(3) A step of curing the coating layer by irradiating the film with ionizing radiation while heating the film so that the film surface temperature is 25 ° C. or higher in an atmosphere having an oxygen concentration of 3% by volume or less.
[6] A method for producing an optical film having at least one functional layer on a transparent substrate, wherein the layer forming method according to any one of [1] to [5] is applied by ionizing radiation irradiation. An optical process comprising a step of transporting the cured film while heating so that the film surface temperature is 25 ° C. or higher in an atmosphere having an oxygen concentration of 3% by volume or less, following the layer curing step. A method for producing a film.
[7] The heating performed during and / or before the ionizing radiation irradiation and / or the heating after the ionizing radiation irradiation is performed so that the film surface temperature is 25 ° C. or higher and 170 ° C. or lower. The manufacturing method of the optical film in any one of said [3]-[6].
[8] The above-mentioned [3], wherein the heating performed at and / or before the irradiation of the ionizing radiation and / or the heating after the irradiation of the ionizing radiation is performed by bringing the film into contact with a heated roll. -The manufacturing method of the optical film in any one of [7].
[9] The above [3] to [3], wherein the heating performed at and / or before the irradiation of the ionizing radiation and / or the heating after the irradiation of the ionizing radiation is performed by blowing heated nitrogen gas. 7] The manufacturing method of the optical film in any one of.
[10] In the method for producing an optical film according to any one of [1] to [9], the transporting step and / or the curing step by irradiation with ionizing radiation are each performed in a low oxygen concentration zone substituted with nitrogen. And a method for producing an optical film, characterized by exhausting nitrogen in a zone for performing a curing step by irradiation with ionizing radiation to a zone for performing a previous step and / or a zone for performing a subsequent step.
[11] A method for producing an optical film having at least one functional layer on a transparent substrate, including at least one layer laminated on the transparent substrate, including the following steps (1) to (3): And the manufacturing method (layer formation method (II)) characterized by forming by the layer formation method in which process (2) and (3) are performed continuously.
(1) A step of coating an application layer on a transparent substrate,
(2) A step of irradiating the film having the coating layer with ionizing radiation in an atmosphere having an oxygen concentration of 3% by volume or less,
(3) A step of maintaining the film after irradiation with ionizing radiation at a film surface temperature of 60 ° C. or less in an atmosphere having an oxygen concentration of 3% by volume or less.
[12] In the method for producing an optical film described in [11] above, before the step of irradiating with ionizing radiation in an atmosphere having an oxygen concentration of 3% by volume or less, at the time of the ionizing radiation irradiation step with an oxygen concentration of 3% by volume or less. The manufacturing method of the optical film characterized by having the process conveyed in the atmosphere more than oxygen concentration of this.
[13] Temperature difference between the film surface temperature in the step of irradiating the ionizing radiation and the film surface temperature in the step of maintaining the film surface temperature at 60 ° C. or lower in an atmosphere having an oxygen concentration of 3% by volume or lower that is continuous with this step. Is within 20 degreeC, The manufacturing method of the optical film as described in said [11] or [12] characterized by the above-mentioned.
[14] A method for producing an optical film having at least one functional layer on a transparent substrate, wherein at least one layer laminated on the transparent support includes the following steps (1) and (2): A method for producing an optical film (layer forming method (III)), which is characterized by being formed by a layer forming method.
(1) A step of applying and drying a coating liquid containing an ionizing radiation curable compound on a web containing a transparent substrate that continuously runs, and forming a coating layer;
(2) The coating layer on the web is irradiated with ionizing radiation in an atmosphere having an oxygen concentration of 3% by volume or less, and an atmosphere having an oxygen concentration of 3% by volume or less for 0.5 seconds or longer from the start of ionizing radiation irradiation. Maintaining the web underneath and curing the coating layer.
[15] A method for producing an optical film having at least one functional layer on a transparent substrate, wherein at least one layer laminated on the transparent support includes the following steps (1) to (3): And the manufacturing method (layer formation method (III-1)) characterized by forming by the layer formation method in which process (2) and (3) is performed continuously.
(1) A step of applying and drying a coating liquid containing an ionizing radiation curable compound on a web containing a transparent substrate that continuously runs, and forming a coating layer;
(2) a step of spraying an inert gas directly on the surface of the coating layer on the web;
(3) The coating layer on the web is irradiated with ionizing radiation in an atmosphere having an oxygen concentration of 3% by volume or less, and an atmosphere having an oxygen concentration of 3% by volume or less for 0.5 seconds or longer from the start of ionizing radiation irradiation. Maintaining the web underneath and curing the coating layer.
[16] A method for producing an optical film having at least one functional layer on a transparent substrate, wherein at least one layer laminated on the transparent support includes the following steps (1) and (2): A method for producing an optical film (layer forming method (IV)), characterized by being formed by a layer forming method.
(1) A step of applying and drying a coating liquid containing an ionizing radiation curable compound on a web containing a transparent substrate that continuously runs, and forming a coating layer;
(2) The coating layer on the web is irradiated with ionizing radiation in an atmosphere having an oxygen concentration of 3% by volume or less, and an oxygen concentration of 3 volume is maintained until the polymerization reaction of the ionizing radiation curable compound is completed by 50% or more. % Maintaining the web under an atmosphere of less than or equal to% and curing the coating layer.
[17] A method for producing an optical film having at least one functional layer on a transparent substrate, wherein at least one layer laminated on the transparent support includes the following steps (1) to (3): And the manufacturing method (layer formation method (IV-1)) characterized by forming by the layer formation method in which process (2) and (3) are performed continuously.
(1) A step of applying and drying a coating liquid containing an ionizing radiation curable compound on a web containing a transparent substrate that continuously runs, and forming a coating layer;
(2) a step of spraying an inert gas directly on the surface of the coating layer on the web;
(3) The coating layer on the web is irradiated with ionizing radiation in an atmosphere having an oxygen concentration of 3% by volume or less, and the oxygen concentration of 3 volume is maintained until the polymerization reaction of the ionizing radiation curable compound is completed by 50% or more. % Maintaining the web under an atmosphere of less than or equal to% and curing the coating layer.
[18] In the method for producing an optical film as described in [17] above, before the step of irradiating the web with ionizing radiation in an atmosphere having an oxygen concentration of 3% by volume or less, an oxygen concentration of 3% by volume or less and ionizing radiation is applied. A method for producing an optical film, comprising a step of conveying the web in an atmosphere having an oxygen concentration equal to or higher than an oxygen concentration in the irradiating step.
[19] In the curing step of the coating layer, the ionizing radiation is irradiated to the coating layer on the web a plurality of times in an atmosphere having an oxygen concentration of 3% by volume or less, and at least two of these ionizing radiations are continuously applied. The method for producing an optical film as described in any one of [14] to [18], wherein the method is performed in an ionizing radiation reaction chamber having an oxygen concentration of 3% by volume or less.
[20] The method for producing an optical film as described in any one of [14] to [19] above, wherein the curing step is performed while heating so that the coating layer surface temperature on the web is 60 ° C. or higher. A method for producing an optical film.
[21] A method for continuously producing an optical film having at least one functional layer on a transparent substrate in a web state, wherein at least one of the layers laminated on the transparent support is the following (1) and A method for producing an optical film (layer forming method (V)), characterized in that the optical film is formed by a layer forming method including the step (2).
(1) A step of applying and drying a coating solution containing at least one oxime-based polymerization initiator on a transparent web substrate to form a coating layer, (2) a coating layer on the transparent web substrate, Irradiating with ionizing radiation in an atmosphere with an oxygen concentration of 3% by volume or less, and maintaining the transparent web substrate in an atmosphere with an oxygen concentration of 3% by volume or less for 0.5 seconds or more from the start of irradiation with ionizing radiation. The step of curing the coating layer.
[22] A method for continuously producing an optical film having at least one functional layer on a transparent substrate in a web state, wherein at least one of the layers laminated on the transparent support is the following (1) and A method for producing an optical film (layer formation method (V-1)), characterized in that the optical film is formed by a layer formation method including the step (2).
(1) A step of applying and drying a coating liquid containing at least one oxime polymerization initiator on a transparent web substrate to form a coating layer;
(2) The coating layer on the transparent web substrate is irradiated with ionizing radiation while being heated so that the film surface temperature is 60 ° C. or higher in an atmosphere having an oxygen concentration of 3% by volume or less, thereby curing the coating layer. Process.
[23] A method for continuously producing an optical film having at least one functional layer on a transparent substrate in a web state, wherein at least one of the layers laminated on the transparent support is the following (1) and A method for producing an optical film (layer formation method (V-2)), characterized in that the optical film is formed by a layer formation method including the step (2).
(1) A step of applying and drying a coating liquid containing at least one oxime polymerization initiator on a transparent web substrate to form a coating layer;
(2) Irradiating the coating layer on the transparent web substrate with ionizing radiation while heating so that the film surface temperature is 60 ° C. or higher in an atmosphere having an oxygen concentration of 3% by volume or less, and starting irradiation with ionizing radiation For 0.5 second or more, and maintaining the transparent web substrate in an atmosphere having an oxygen concentration of 3% by volume or less to cure the coating layer.
[24] In the step of curing the coating layer, the coating layer on the web is irradiated with the ionizing radiation a plurality of times in an atmosphere having an oxygen concentration of 3% by volume or less, and at least two of these ionizing radiations are continuously applied. The method for producing an optical film as described in any one of the above [21] to [23], which is performed in an ionizing radiation reaction chamber having an oxygen concentration of 3% by volume or less.
[25] In the method for producing an optical film according to any one of [14] to [24], an anterior chamber in which an inert gas is injected into the web having the continuously running coating layer to have a low oxygen concentration. And the web is further carried into an ionizing radiation reaction chamber having an oxygen concentration of 3% by volume or less into which an inert gas is installed continuously with the anterior chamber, and the coating layer in the ionizing radiation reaction chamber is loaded with the web. A method for producing an optical film, comprising performing a curing step.
[26] The method for producing an optical film as described in [25] above, wherein the inert gas injected into the ionizing radiation reaction chamber is blown out from at least a web entrance side of the ionizing radiation reaction chamber. A method for producing an optical film.
[27] The above [25], wherein the gap between the ionizing radiation reaction chamber and the front chamber constituting the web entrance side with the coating layer surface on the web is 0.2 to 15 mm. ] Or the manufacturing method of the optical film as described in [26].
[28] At least one of the surfaces constituting the web entrance side of the ionizing radiation reaction chamber and the front chamber is movable, and passes through the joining member joining the web. The structure according to any one of the above [25] to [27], wherein at least the thickness of the joining member is escaped (that is, the gap is increased by at least the thickness). Manufacturing method of optical film.
[29] The method for producing an optical film as described in any one of [1] to [28], wherein the ionizing radiation is ultraviolet rays.
[30] The method for producing the optical film, wherein the land of the tip lip of the slot die is brought close to the surface of the web continuously supported by a backup roll, and the coating liquid is applied from the slot of the tip lip. Have
When the coating liquid has a land length in the web traveling direction of the tip lip on the web traveling direction side of the slot die of 30 μm or more and 100 μm or less, and the slot die is set at the coating position, the traveling direction of the web The gap between the tip lip on the opposite side of the web and the web is applied using a coating apparatus installed so that the gap between the tip lip on the web traveling direction side and the web is 30 μm or more and 120 μm or less. The method for producing an optical film according to any one of [1] to [29].
[31] The viscosity of the coating solution applied is 2.0 [mPa · sec] or less, and the amount of the coating solution applied to the web surface is 2.0 to 5.0 [ml / m ² ]. The method for producing an optical film as described in [30] above, wherein
[32] The method for producing an optical film as described in [30] or [31], wherein the coating solution is applied to a continuously running web surface at a speed of 25 [m / min] or more.
[33] An optical film produced by the production method according to any one of [1] to [32].
[34] A manufacturing apparatus for producing an optical film having at least one functional layer on a transparent substrate, an ionizing radiation reaction chamber in which ionizing radiation is irradiated, and a front chamber (in other words, in front of the ionizing radiation reaction chamber) For example, a transparent base material that is adjacent to the reaction chamber and has a coating layer in each of the ionizing radiation reaction chamber and the front chamber is provided. A device equipped with a web entrance for carrying in a web, wherein the ionizing radiation reaction chamber and the front chamber are each kept at a low oxygen concentration by injecting an inert gas, and are introduced into the ionizing radiation reaction chamber. The apparatus for producing an optical film, wherein the injected inert gas blows out from the web entrance of the ionizing radiation reaction chamber.
[35] The gap with the surface of the coating layer formed on the web is 0.2 to 15 mm in at least one of the surfaces constituting the web entrance side of the ionizing radiation reaction chamber and the front chamber. The apparatus for producing an optical film according to [34].
[36] In at least one of the surfaces constituting the web entrance side of the ionizing radiation reaction chamber and the front chamber, at least a part of the surface constituting the web entrance side is movable, and passes through the joining member joining the web. The optical film according to the above [34] or [35], wherein at least the thickness of the joining member is escaped (that is, the gap is increased by at least the thickness). Manufacturing equipment.
[37] An antireflection film produced by the method according to any one of [1] to [32].
[38] Any one of the above [1] to [32], wherein the functional layer has a low refractive index layer having a thickness of 200 nm or less, and the low refractive index layer is formed by the layer forming method. The antireflection film as described in 1.
[39] The antireflection film as described in [38] above, wherein the low refractive index layer constituting the antireflection film contains a fluorine-containing polymer.
[40] The antireflection film as described in [39] above, wherein the fluoropolymer is a fluoropolymer represented by the following general formula 1.

[In General Formula 1, L represents a linking group having 1 to 10 carbon atoms, and m represents 0 or 1. X represents a hydrogen atom or a methyl group. A represents a polymerization unit of any vinyl monomer, and may be a single component or a plurality of components. x, y, and z represent mol% of each constituent component, and represent values satisfying 30 ≦ x ≦ 60, 5 ≦ y ≦ 70, and 0 ≦ z ≦ 65. ]
[41] The antireflection film as described in any one of [38] to [40], wherein the low refractive index layer contains hollow silica fine particles.
[42] A polarizing plate comprising a polarizing film and a protective film laminated on both surfaces thereof, wherein at least one of the two protective films has any one of the above [37] to [41] A polarizing plate using the antireflection film as described above.
[43] An image display device comprising the antireflection film according to any one of [37] to [41] or the polarizing plate according to [42] on an outermost surface of a display.

By the method for producing an optical film of the present invention, in particular, the method for producing an antireflection film, an antireflection film having sufficient antireflection ability and improved scratch resistance can be provided.
The image display device provided with the antireflection film or polarizing plate produced according to the present invention has little reflection of external light and reflection of the background, has extremely high visibility, and excellent scratch resistance.

  Hereinafter, the present invention will be described in detail. In the present specification, when a numerical value represents a physical property value, a characteristic value, etc., the description “(numerical value 1) to (numerical value 2)” means “(numerical value 1) or more and (numerical value 2) or less”. .

[Layer structure of optical film]
The optical film of the present invention has at least one functional layer on a transparent substrate (hereinafter also referred to as a substrate film). Examples of the functional layer herein include an antistatic layer, a hard coat layer (cured resin layer), an antireflection layer, an antiglare layer, an optical compensation layer, an alignment layer, and a liquid crystal layer. The antireflection film has a hard coat layer, which will be described later, on the transparent base material as necessary, and further has a refractive index, a film thickness, the number of layers and a layer order so that the reflectance is reduced by optical interference. The antireflection layer is laminated in consideration of the above. Hereinafter, the optical film of the present invention will be described in detail by taking an antireflection film as an example. The method for producing the optical film of the present invention is described in JP-A-9-73081 and JP-A-9-73016. This method can also be applied to the method for producing a high-hardness surface film described in JP-A-2003-335984 and JP-A-2003-341006.
The simplest configuration of the antireflection film is a substrate in which only a low refractive index layer is coated. In order to further reduce the reflectance, the antireflection layer is preferably composed of a combination of a high refractive index layer having a higher refractive index than the substrate and a low refractive index layer having a lower refractive index than the substrate. Examples of configurations include two layers of a high refractive index layer / low refractive index layer from the base material side, and three layers having different refractive indices, a medium refractive index layer (having a higher refractive index than the base material or the hard coat layer). , A layer having a lower refractive index than a high refractive index layer) / a high refractive index layer / a low refractive index layer, and the like. Among them, from the viewpoint of durability, optical properties, cost, productivity, etc., it has an antireflection layer laminated in the order of medium refractive index layer / high refractive index layer / low refractive index layer on a substrate having a hard coat layer. Are preferred. Further, the antireflection film of the present invention may have an antiglare layer, an antistatic layer or the like.

The example of the preferable structure of the antireflection film of this invention is shown below.
Base film / low refractive index layer,
Base film / antiglare layer / low refractive index layer,
Base film / hard coat layer / antiglare layer / low refractive index layer,
Base film / hard coat layer / high refractive index layer / low refractive index layer,
Base film / hard coat layer / medium refractive index layer / high refractive index layer / low refractive index layer,
Base film / antiglare layer / high refractive index layer / low refractive index layer,
Base film / antiglare layer / medium refractive index layer / high refractive index layer / low refractive index layer,
Base film / antistatic layer / hard coat layer / medium refractive index layer / high refractive index layer / low refractive index layer,
Antistatic layer / base film / hard coat layer / medium refractive index layer / high refractive index layer / low refractive index layer,
Base film / antistatic layer / antiglare layer / medium refractive index layer / high refractive index layer / low refractive index layer,
Antistatic layer / base film / antiglare layer / medium refractive index layer / high refractive index layer / low refractive index layer,
Antistatic layer / base film / antiglare layer / high refractive index layer / low refractive index layer / high refractive index layer / low refractive index layer.
In the above, the anti-glare layer may be an internal scattering layer having no irregularities on the surface.
The antireflection film of the present invention is not particularly limited to these layer configurations as long as the reflectance can be reduced by optical interference. The high refractive index layer may be a light diffusing layer having no antiglare property. The antistatic layer is preferably a layer containing conductive polymer particles or metal oxide fine particles (for example, SnO ₂ , ITO), and can be provided by coating or atmospheric pressure plasma treatment.

[Method for forming film]
The method for producing an optical film of the present invention is characterized in that at least one of the layers laminated on the transparent substrate of the optical film is formed by any one of the following (I) to (V) layer forming methods. . In particular, when the optical film is an antireflection film, it is preferable that the low refractive index layer as the outermost layer is formed by the following layer forming method.

(Layer formation method (I))
A layer forming method including the following steps (1) and (2).
(1) A step of coating an application layer on a transparent substrate,
(2) A step of curing the coating layer by irradiating ionizing radiation in an oxygen concentration atmosphere lower than the oxygen concentration in the atmosphere.

Hereinafter, the layer forming method (I) according to the present invention will be described.
The coating layer on the transparent substrate is formed by applying a coating composition (coating liquid) of the layer to be formed on the transparent substrate and drying it. The method for applying the coating solution is not particularly limited. In addition, the transparent substrate of the present invention may be either cut out or web-like, but is preferably web-like in terms of production cost.

The step of irradiating with ionizing radiation is an environment where the oxygen concentration is lower than the atmospheric oxygen concentration, preferably 3% by volume or less, more preferably 1% by volume or less, and even more preferably 0.1% by volume or less from the viewpoint of film hardness. Perform below.
In the step of irradiating the ionizing radiation, it is necessary that the oxygen concentration is lower than the oxygen concentration in the atmosphere.

In the layer forming method (I), immediately before the step of irradiating the film on which the coating layer has been applied (coated / dried) with ionizing radiation, the film is subjected to an atmosphere having a low oxygen concentration lower than the atmospheric oxygen concentration (hereinafter referred to as irradiation). It is preferable to provide a step of conveying in a pre-low oxygen concentration zone. By performing the curing step by ionizing radiation irradiation continuously with the conveying step, the oxygen concentration inside the coating film surface and inside can be effectively reduced, and curing can be promoted.
In addition, the aspect which performs a hardening process continuously with a conveyance process is the air | atmosphere immediately before approaching an ionizing radiation irradiation zone for the film carried in the low oxygen concentration atmosphere (henceforth an ionizing radiation irradiation zone) which performs a hardening process. This is a mode in which a low oxygen concentration zone lower than the oxygen concentration in the inside is passed. For example, a mode in which the conveyance step and the curing step are sequentially performed in the same chamber maintained at a low oxygen concentration is also conceivable. The transporting process may include a film drying process.
The upper limit of the oxygen concentration in the transport step before the ionizing radiation irradiation may be less than the oxygen concentration in the atmosphere, preferably 15% by volume or less, more preferably 10% by volume or less, and most preferably 5% by volume or less.
Further, the lower limit of the oxygen concentration in the transporting step before the ionizing radiation irradiation may be an oxygen concentration equal to or higher than the step of irradiating ionizing radiation from the viewpoint of cost.

Moreover, in the said layer formation method, it is preferable to heat a film at the time of the ionizing radiation irradiation process and / or the conveyance process before ionizing radiation irradiation. The heating temperature of the film is preferably such that the film surface of the film is 25 ° C or higher, more preferably the film surface is 25 ° C to 170 ° C, more preferably 60 ° C to 170 ° C, and most preferably 80 ° C. Heat to ~ 130 ° C. By heating at the time of the conveyance process before ionizing radiation irradiation, smooth heating at the time of ionizing radiation irradiation can be promoted. On the other hand, by heating at the time of irradiation with ionizing radiation, the curing reaction initiated by ionizing radiation is accelerated by heat, and a film excellent in physical strength and chemical resistance can be formed. By making the temperature 25 ° C. or higher, the effect of heating can be easily obtained. The film surface means the vicinity of the film surface of the layer to be cured.
Further, the time during which the film surface is maintained at the above temperature is preferably from 0.1 second to 300 seconds, more preferably from 0.1 second to 10 seconds from the start of ionizing radiation irradiation. If the time for maintaining the film surface temperature in the above temperature range is too short, the reaction of the curable composition forming the film cannot be promoted. On the other hand, if the length is too long, the optical performance of the film deteriorates, and manufacturing problems such as an increase in equipment occur.
The heating method is not particularly limited, but a method of heating the roll to contact the film, a method of spraying heated nitrogen, irradiation with far infrared rays or infrared rays is preferable. A method of flowing hot water or steam through a rotating metal roll described in Japanese Patent No. 2523574 can also be used.

A more preferred embodiment of the layer forming method (I) is shown below.
(Layer formation method (I) -1)
A layer forming method comprising the following steps (1) to (3), wherein the following (2) conveying step and (3) curing step are continuously performed.
(1) A step of coating an application layer on a transparent substrate,
(2) A step of transporting the film having the coating layer in an oxygen concentration atmosphere lower than the oxygen concentration in the air,
(3) A step of irradiating the film with ionizing radiation in an atmosphere having an oxygen concentration of 3% by volume or less to cure the coating layer.

(Layer formation method (I) -2)
A layer forming method comprising the following steps (1) to (3), wherein the following (2) conveying step and (3) curing step are continuously performed.
(1) A step of coating an application layer on a transparent substrate,
(2) A step of transporting the film having the coating layer in an oxygen concentration atmosphere lower than the oxygen concentration in the air,
(3) A step of curing the coating layer by irradiating the film with ionizing radiation while heating the film so that the film surface temperature is 25 ° C. or higher in an atmosphere having an oxygen concentration of 3% by volume or less.

(Layer formation method (I) -3)
A layer forming method comprising the following steps (1) to (3), wherein the following (2) conveying step and (3) curing step are continuously performed.
(1) A step of coating an application layer on a transparent substrate,
(2) A step of conveying the film having the coating layer in an oxygen concentration atmosphere lower than the oxygen concentration in the atmosphere while heating the film surface temperature to be 25 ° C. or higher,
(3) A step of irradiating the film with ionizing radiation in an atmosphere having an oxygen concentration of 3% by volume or less to cure the coating layer.

(Layer formation method (I) -4)
A layer forming method comprising the following steps (1) to (3), wherein the following (2) conveying step and (3) curing step are continuously performed.
(1) A step of coating an application layer on a transparent substrate,
(2) A step of conveying the film having the coating layer in an oxygen concentration atmosphere lower than the oxygen concentration in the atmosphere while heating the film surface temperature to be 25 ° C. or higher,
(3) A step of curing the coating layer by irradiating the film with ionizing radiation while heating the film so that the film surface temperature is 25 ° C. or higher in an atmosphere having an oxygen concentration of 3% by volume or less.

In the layer forming method (layer forming method and layer forming method (I) -1 to 4), the cured film is further subjected to an oxygen concentration of 3% by volume or less continuously in the curing step by irradiation with ionizing radiation. You may have the process conveyed, heating film surface temperature to 25 degreeC or more.
The oxygen concentration during the conveying step after curing is more preferably 3% by volume or less, still more preferably 1% by volume or less. The film surface temperature at the time of heating, the holding time of the film surface temperature, the heating method, and the like are the same as those in the transport step before curing described above.
By heating the film after irradiation with ionizing radiation, there is an effect that the polymerization reaction further proceeds even in the polymer film formed with time.
By these layer forming methods, it is possible to produce an antireflection film having improved anti-scratch properties while having sufficient antireflection performance.

  As a means for reducing the oxygen concentration, the atmosphere (nitrogen concentration of about 79% by volume, oxygen concentration of about 21% by volume) is preferably replaced with another inert gas, and replacement with nitrogen (nitrogen purge) is particularly preferable. .

In the production method of the present invention, the steps of irradiating with ionizing radiation, the transporting step before irradiating with ionizing radiation, and the heating step after irradiation with ionizing radiation performed as necessary are separated from each other. Alternatively, it may be performed in a low oxygen concentration atmosphere (low oxygen concentration concentration zone) controlled to a desired oxygen concentration, which may be continuous. From the viewpoint of reducing the production cost, the inert gas used to lower the oxygen concentration in the ionizing radiation irradiation zone is used as a low oxygen concentration zone (pre-irradiation low oxygen concentration zone) and / or after that. It is preferable to exhaust to a low oxygen concentration zone where the process is performed (low oxygen concentration zone after irradiation) and to effectively use the inert gas.
Note that the present invention is not limited to the above process, and any process may be performed in a low oxygen concentration atmosphere. Moreover, when ionizing radiation irradiation is performed by dividing the ionizing radiation irradiation zone into a plurality of zones, a low oxygen concentration zone may be provided between the zones.

(Layer formation method (II))
The layer forming method (II) is a method for producing an optical film having at least one functional layer on a transparent substrate, and includes at least one layer (at least one functional layer) laminated on the transparent substrate. A method for producing an optical film, comprising the following steps (1) to (3) and a layer forming method in which steps (2) and (3) are continuously performed.
(1) A step of coating an application layer on a transparent substrate,
(2) A step of irradiating the film having the coating layer with ionizing radiation in an atmosphere having an oxygen concentration of 3% by volume or less,
(3) A step of maintaining the film after irradiation with ionizing radiation at a film surface temperature of 60 ° C. or less in an atmosphere having an oxygen concentration of 3% by volume or less.

Hereinafter, the layer forming method (II) will be described.
At least one of the above functional layers of the optical film, particularly the antireflection film, has a film surface temperature in an atmosphere having an oxygen concentration of 3% by volume or less continuously with the step of irradiating ionizing radiation in an atmosphere having an oxygen concentration of 3% by volume or less. It is cured and formed by a process of maintaining the temperature to be 60 ° C. or lower.
As described above, by providing a step of maintaining the film surface temperature at 60 ° C. or lower in an atmosphere having an oxygen concentration of 3% by volume or less continuously with the step of irradiating ionizing radiation at an oxygen concentration of 3% by volume or less. The film can be sufficiently cured to form a film excellent in physical strength and chemical resistance. Further, since the film surface temperature is kept low at 60 ° C. or lower during curing, not only the film formation is stable and the surface shape is excellent, but also performance such as scratch resistance can be made uniform in the surface.
The oxygen concentration at the time of ionizing radiation irradiation is 3% by volume or less, preferably 1% by volume or less, and more preferably 0.1% or less. Moreover, the oxygen concentration in the process after ionizing radiation irradiation is 3 volume%, Preferably it is 1 volume% or less, More preferably, it is 0.1 volume% or less.
As a means for reducing the oxygen concentration, it is preferable to replace the atmosphere (nitrogen concentration of about 79% by volume, oxygen concentration of about 21% by volume) with another inert gas, particularly preferably with nitrogen (nitrogen purge). It is.

In the layer forming method (II), a step of maintaining the film surface temperature of the optical film at 60 ° C. or lower in an atmosphere having an oxygen concentration of 3% by volume or lower is performed continuously with ionizing radiation irradiation. The film surface temperature of the optical film is preferably maintained at 30 to 60 ° C., more preferably 40 to 60 ° C. If the temperature is too low, the curing progresses slowly and the rub resistance deteriorates.On the other hand, if the temperature is too high, handling problems such as wrinkles occur in the surface and the uniformity of the in-plane performance also deteriorates. Resulting in.
Although there is no particular limitation on the film surface temperature at the time of ionizing radiation irradiation, the film surface temperature in the step of maintaining the film surface temperature at 60 ° C. or less after ionizing radiation irradiation from the uniformity of handling properties and in-plane performance The difference from the film surface temperature during irradiation with ionizing radiation is preferably within 20 ° C., more preferably 10 ° C. or less.
The time during which the film is kept at the above temperature after irradiation with ionizing radiation is preferably from 0.1 second to 300 seconds, more preferably from 0.1 second to 10 seconds from the end of irradiation with ionizing radiation. If the time for keeping the film surface temperature in the above temperature range is too short, the reaction of the curable composition that forms the film cannot be promoted. Manufacturing problems such as enlargement also occur.
Although there is no particular limitation on the method of bringing the film surface temperature of the film to a desired temperature of 60 ° C. or less, a method of heating a roll to contact the film, a method of blowing heated nitrogen, irradiation of far infrared rays or infrared rays is preferable. . A method of flowing hot water or steam through a rotating metal roll described in Japanese Patent No. 2523574 can also be used. On the other hand, when the film surface temperature of the film is likely to exceed 60 ° C. due to irradiation with ionizing radiation, a method of cooling the roll and bringing it into contact with the film can be used.
When the optical film is an antireflection film, it is preferable that a low refractive index layer, which is the outermost layer, be formed by this method.

Furthermore, in the layer forming method (II), before the ionizing radiation irradiation step, the coating film before passing through the ionizing radiation irradiation step is an atmosphere having an oxygen concentration of 3% by volume or less and an oxygen concentration at the time of the ionizing radiation irradiation step (hereinafter, It is preferable to have a step of conveying in a pre-irradiation low oxygen zone). By carrying it in an atmosphere having a low oxygen concentration before the step of irradiating with ionizing radiation, the oxygen concentration inside the coating film surface and inside can be effectively reduced, and curing can be promoted. The conveyance here may be an embodiment in which a film having a coating film on a transparent substrate passes through a pre-irradiation low oxygen zone and is continuously irradiated with ionizing radiation. May include a drying step and a heating step.
The oxygen concentration in the transport step before ionizing radiation irradiation is preferably 3% by volume or less, more preferably 1% volume or less, and further preferably 0.1% or less. Further, the lower limit of the oxygen concentration in the transporting step before the ionizing radiation irradiation can be optimized as appropriate from the equipment investment and running cost, but is preferably equal to or higher than the oxygen concentration in the ionizing radiation irradiation step.

(Layer formation method (III))
The method for producing an optical film of the layer forming method (III) has a step of forming at least one functional layer on the transparent substrate by the following steps (1) and (2).
(1) The process of apply | coating and drying the coating liquid containing an ionizing radiation curable compound on the web containing a transparent base material which drive | works continuously, and forms an application layer,
(2) The coating layer on the web is irradiated with ionizing radiation in an atmosphere having an oxygen concentration of 3% by volume or less, and an atmosphere having an oxygen concentration of 3% by volume or less for 0.5 seconds or longer from the start of ionizing radiation irradiation. A step of maintaining the web under and curing the coating layer (hereinafter, the step of curing the coating layer of (2) may be referred to as a “curing step”).
Hereinafter, the layer forming method (III) will be described.

Irradiation with ionizing radiation is performed in an atmosphere having an oxygen concentration of 3% by volume or less. More preferably, it is 1 volume% or less, More preferably, it is 0.1 volume% or less. In order to reduce the oxygen concentration more than necessary, a large amount of inert gas is required, which is not preferable from the viewpoint of production cost. As a means for reducing the oxygen concentration, it is preferable to replace the atmosphere (nitrogen concentration of about 79% by volume, oxygen concentration of about 21% by volume) with another inert gas, particularly preferably with nitrogen (nitrogen purge). It is.
In the layer forming method (III), the coating layer on the web is irradiated with ionizing radiation in an atmosphere having an oxygen concentration of 3% by volume or less, and the atmosphere having an oxygen concentration of 3% by volume or less is applied for 0.5 seconds or more from the start of irradiation. The coating layer is cured by maintaining under. In the layer forming method (III), it is preferable to maintain the web in an atmosphere having an oxygen concentration of 3% by volume or less even after the end of ionizing radiation irradiation. The maintenance time is preferably 0.7 seconds to 60 seconds, more preferably 0.7 seconds to 10 seconds from the start of irradiation. If it is less than 0.5 seconds, the curing reaction cannot be completed and sufficient curing cannot be performed. The oxygen concentration at the time of maintenance is more preferably 1% by volume or less, and still more preferably 0.1% by volume or less. Maintaining low oxygen conditions for a long time is not preferable because the equipment becomes large and a large amount of inert gas is required.
In the present specification, the “web” may be the base material itself or may be one in which another functional layer is formed on the base material.

In the layer forming method (III), it is preferable that the curing step is performed in an ionizing radiation irradiation reaction chamber (hereinafter sometimes simply referred to as “reaction chamber”) controlled to a desired oxygen concentration. When supplying the inert gas to the ionizing radiation reaction chamber, the reaction chamber is designed to remove the air transported by the web transport by slightly blowing it to the web entrance side of the reaction chamber (the entrance to which the web is loaded). Can be effectively reduced, and the substantial oxygen concentration on the extreme surface where the inhibition of curing by oxygen is large can be efficiently reduced. The direction of the inert gas flow on the web entrance side of the reaction chamber can be controlled by adjusting the balance between supply and exhaust of the reaction chamber. In addition, it is also preferable as a method for removing the carried air that the inert gas is blown directly on the surface of the coating layer on the web immediately before the coating layer on the web is irradiated with ionizing radiation.
In particular, it is preferable that the low refractive index layer which is the outermost layer and is thin is cured by this method.

It is also preferable to provide a front chamber before the reaction chamber. The anterior chamber is preferably replaced with an inert gas and has a low oxygen concentration, preferably an oxygen concentration of 3% or less and an oxygen concentration of the reaction chamber or more. It may be possible to simply pass (carry) the web before irradiation with ionizing radiation through the front chamber, and by directly spraying the surface of the coating layer on the web of the inert gas, which is a method for removing the above-described conducted air. Also good.
By providing the front chamber and excluding oxygen on the surface of the coating layer of the web in advance, it becomes possible to maintain a low oxygen concentration in the reaction chamber, and the curing can proceed more efficiently.

Further, at least one of the side surfaces constituting the web entrance side of the ionizing radiation reaction chamber or the front chamber has a gap of 0.2 to 15 mm with the surface of the coating layer on the web in order to use the inert gas efficiently. It is preferable that the thickness is 0.2 to 10 mm, and most preferably 0.2 to 5 mm. Here, the gap refers to the length between the surface of the coating layer on the web and the upper end of the web entrance on the side surface constituting the web entrance side.
However, in order to continuously manufacture the web, it is necessary to join and connect the webs, and a method of sticking with a joining tape or the like is widely used for joining. For this reason, if the gap between the entrance of the ionizing radiation reaction chamber or the front chamber and the surface of the coating layer on the web is too narrow, there arises a problem that the joining member such as the joining tape is caught. For this reason, in order to narrow the gap, it is preferable to make at least a part of the entrance surface of the ionizing radiation reaction chamber or the front chamber movable and to widen the gap by the junction thickness when the junction enters. In order to realize this, (A) an ionization radiation reaction chamber or an entrance surface of an anterior chamber is made movable forward and backward, and when the joint passes, it moves forward and backward to widen the gap, or (B) The entrance surface of the ionizing radiation reaction chamber or the front chamber can be moved vertically with respect to the web surface, and the gap can be widened by moving up and down as the joint passes.

Hereinafter, taking the operation of the web entrance surface of the front chamber as an example, an example of the operation of the reaction chamber or the web entrance surface of the front chamber applicable in the layer forming method (III) will be described based on FIGS. In the following description of the drawings, a web having a coating layer (not shown) is simply referred to as “web”).
FIG. 1 is a schematic view of a production apparatus having an ionizing radiation reaction chamber and an anterior chamber used in the layer forming method (III).
FIG. 2 is a side view showing an example of the operation of the web entrance surface of the production apparatus equipped with the ionizing radiation reaction chamber and the front chamber used in the layer forming method (III), and shows the mode (A). . The apparatus having the configuration of FIG. 2 detects a joining member with a sensor before the joining member that joins and joins the web enters the front chamber entrance at the time of web conveyance, and the sensor and the sensor through a control unit (not shown). An air cylinder attached to at least a part of the web entrance surface of the anterior chamber that operates in conjunction with it allows the entrance surface to be moved back and forth in the direction of web travel, thereby escaping the thickness of the joining member. It is something that can be done.

  3 and 4 are views showing the above-described embodiment (B), FIG. 3 is a view schematically showing the web entrance surface of the front chamber, and FIG. 4 is an operation of the web entrance surface of the front chamber. FIG. A gap between the web and the entrance surface is determined by making a part of the web entrance surface of the front chamber movable and contacting both ends of the web with the bearing touch roll. When the joining member passes, the bearing touch roll gets over the joining member, and the gap at the web entrance surface is kept constant. The moving means at the entrance is not limited as long as it can escape the joint.

In the layer formation method (III), when the coating layer on the web is cured, it is also preferable to perform the ionizing radiation irradiation performed in an atmosphere of 3% by volume or less in the curing step in a plurality of times.
In this case, it is preferable that the ionizing radiation irradiation is performed at least twice in a reaction chamber having a continuous oxygen concentration of 3% by volume or less. By performing multiple times of ionizing radiation irradiation in the same low oxygen concentration reaction chamber, the reaction time required for curing can be effectively ensured. In particular, when the production speed is increased for high productivity, multiple ionizing radiation irradiations are required to secure the energy of ionizing radiation necessary for the curing reaction, and this is combined with ensuring the reaction time necessary for the curing reaction. The above aspect is effective.
“Consecutive reaction chamber” refers to an embodiment in which ionizing radiation is irradiated at least twice in a reaction chamber having an oxygen concentration of 3% by volume or at least two reaction chambers having an oxygen concentration of 3% by volume or less. There is an embodiment in which the gap is a low oxygen zone having an oxygen concentration of 3 vol% or less. In the latter case, each reaction chamber may have a different oxygen concentration as long as the oxygen concentration is 3% by volume or less.

  It is also preferable to perform the curing step while heating the web such that the coating layer surface temperature is 60 ° C. or higher by the layer forming method (III). By performing the curing step while heating, the curing reaction is accelerated by heat, and a film excellent in physical strength and chemical resistance can be formed.

  The heating is preferably performed at a coating layer surface temperature of 60 ° C. or higher and 170 ° C. or lower. When the temperature is lower than 60 ° C., the curing by heating is small, while when the temperature exceeds 170 ° C., problems such as deformation of the base material occur. A more preferable temperature is 60 ° C to 100 ° C. Further, the time for which the surface temperature of the coating layer reaches the above temperature is preferably 0.1 second or more and 300 seconds or less from the start of ionizing radiation irradiation, and more preferably 10 seconds or less. If the time for maintaining the temperature of the coating layer surface temperature in the above temperature range is too short, the reaction of the curable composition for forming the film cannot be promoted. There are also problems in manufacturing such as an increase in size.

  The heating method is not particularly limited, but a method of heating a roll to contact the web, a method of spraying heated nitrogen, irradiation with far infrared rays or infrared rays is preferable. A method of heating a rotating metal roll described in Japanese Patent No. 2523574 by flowing a medium such as hot water, steam or oil can also be used. As a heating means, a dielectric heating roll or the like may be used.

(Layer formation method (IV))
The method for producing an optical film of the layer forming method (IV) includes a step of forming at least one functional layer on the transparent substrate by the following steps (1) and (2).
(1) The process of apply | coating and drying the coating liquid containing an ionizing radiation curable compound on the web containing a transparent base material which drive | works continuously, and forms an application layer,
(2) The coating layer on the web is irradiated with ionizing radiation in an atmosphere having an oxygen concentration of 3% by volume or less, and until the polymerization reaction of the ionizing radiation curable compound is completed by 50% or more, the oxygen concentration is 3% by volume. A step of maintaining the web under the following atmosphere and curing the coating layer. (Hereinafter, the step of curing the coating layer of (2) may be referred to as “curing step”).
Hereinafter, the layer forming method (IV) will be described.

The reaction rate (polymerization rate) of the polymerization reaction of the ionizing radiation curable compound can be measured by an infrared absorption measurement method described in Polymer Analysis Handbook (Japan Society for Analytical Chemistry, Polymer Analysis Research Roundtable). More specifically, the corresponding functional layer is applied as a single layer on polyethylene terephthalate or triacetyl cellulose, and a sample is prepared by ionizing radiation curing under a drying step and predetermined conditions. The sample is rubbed with KBr powder, and the rubbed KBr powder is finely mixed in a mortar, and then infrared absorption is measured. The measuring apparatus used was a FT-IR apparatus AVATAR360 manufactured by Nicole Co., Ltd., and the number of integration was 40. The same measurement is performed on a sample that has not been irradiated with ionizing radiation, and the ratio of the measured values obtained from the two samples is defined as the polymerization rate.
When exposed to conditions under an atmosphere with a polymerization rate of less than 50% and an oxygen concentration of more than 3% by volume, the reaction stops and problems such as a decrease in scratch resistance occur. The polymerization rate is more preferably 70% or more and 98% or less, and further preferably 80% or more and 98% or less. However, increasing the polymerization rate more than necessary has problems such as an increase in the amount of inert gas used and an increase in the low oxygen zone.

Irradiation with ionizing radiation is performed in an atmosphere having an oxygen concentration of 3% by volume or less. More preferably, it is 1 volume% or less, More preferably, it is 0.1 volume% or less. In order to reduce the oxygen concentration more than necessary, a large amount of inert gas is required, which is not preferable from the viewpoint of production cost. As a means for reducing the oxygen concentration, it is preferable to replace the atmosphere (nitrogen concentration of about 79% by volume, oxygen concentration of about 21% by volume) with another inert gas, particularly preferably with nitrogen (nitrogen purge). It is.
In the present specification, the “web” may be the base material itself or may be one in which another functional layer is formed on the base material.

In the layer forming method (IV), it is preferable that the curing step is performed in an ionizing radiation irradiation reaction chamber (hereinafter sometimes simply referred to as “reaction chamber”) controlled to a desired oxygen concentration. When supplying the inert gas to the ionizing radiation reaction chamber, the reaction chamber is designed to remove the air transported by the web transport by slightly blowing it to the web entrance side of the reaction chamber (the entrance to which the web is loaded). Can be effectively reduced, and the substantial oxygen concentration on the extreme surface where the inhibition of curing by oxygen is large can be efficiently reduced. The direction of the inert gas flow on the web entrance side of the reaction chamber can be controlled by adjusting the balance between supply and exhaust of the reaction chamber. In addition, it is also preferable as a method for removing the carried air that the inert gas is blown directly on the surface of the coating layer on the web immediately before the coating layer on the web is irradiated with ionizing radiation.
In particular, it is preferable that the low refractive index layer which is the outermost layer and is thin is cured by this method.

It is also preferable to provide a front chamber before the reaction chamber. The anterior chamber is preferably replaced with an inert gas and has a low oxygen concentration, preferably an oxygen concentration of 3% or less and an oxygen concentration of the reaction chamber or more. In the front chamber, it may be possible to only pass (convey) the web before irradiation with ionizing radiation through the front chamber. You may spray.
By providing the front chamber and excluding oxygen on the surface of the coating layer of the web in advance, it becomes possible to maintain a low oxygen concentration in the reaction chamber, and the curing can proceed more efficiently.

Further, at least one of the side surfaces constituting the web entrance side of the ionizing radiation reaction chamber or the front chamber has a gap of 0.2 to 15 mm with the surface of the coating layer on the web in order to use the inert gas efficiently. It is preferable that the thickness is 0.2 to 10 mm, and most preferably 0.2 to 5 mm. Here, the gap refers to the length between the surface of the coating layer on the web and the upper end of the web entrance on the side surface constituting the web entrance side.
However, in order to continuously manufacture the web, it is necessary to join and connect the webs, and a method of sticking with a joining tape or the like is widely used for joining. For this reason, if the gap between the entrance of the ionizing radiation reaction chamber or the front chamber and the surface of the coating layer on the web is too narrow, there arises a problem that the joining member such as the joining tape is caught. For this reason, in order to narrow the gap, it is preferable to make at least a part of the entrance surface of the ionizing radiation reaction chamber or the front chamber movable and to widen the gap by the junction thickness when the junction enters. In order to realize this, (A) an ionization radiation reaction chamber or an entrance surface of an anterior chamber is made movable forward and backward, and when the joint passes, it moves forward and backward to widen the gap, or (B) The entrance surface of the ionizing radiation reaction chamber or the front chamber can be moved vertically with respect to the web surface, and the gap can be widened by moving up and down as the joint passes.

Hereinafter, taking the operation of the web entrance surface of the front chamber as an example, an example of the operation of the reaction chamber or the web entrance surface of the front chamber applicable in the layer forming method (IV) will be described based on FIGS. In the following description of the drawings, a web having a coating layer (not shown) is simply referred to as “web”).
FIG. 1 is a schematic view of a production apparatus including an ionizing radiation reaction chamber and an anterior chamber used in the layer forming method (IV).
FIG. 2 is a side view showing an example of the operation of the web entrance surface of the production apparatus equipped with the ionizing radiation reaction chamber and the front chamber used in the layer forming method (IV), and shows the mode (A). . The apparatus having the configuration of FIG. 2 detects a joining member with a sensor before the joining member that joins and joins the web enters the front chamber entrance at the time of web conveyance, and the sensor and the sensor through a control unit (not shown). An air cylinder attached to at least a part of the web entrance surface of the anterior chamber that operates in conjunction with it allows the entrance surface to be moved back and forth in the direction of web travel, thereby escaping the thickness of the joining member. It is something that can be done.

  3 and 4 are views showing the above-described embodiment (B), FIG. 3 is a view schematically showing the web entrance surface of the front chamber, and FIG. 4 is an operation of the web entrance surface of the front chamber. FIG. A gap between the web and the entrance surface is determined by making a part of the web entrance surface of the front chamber movable and contacting both ends of the web with the bearing touch roll. When the joining member passes, the bearing touch roll gets over the joining member, and the gap at the web entrance surface is kept constant. The moving means at the entrance is not limited as long as it can escape the joint.

In the layer forming method (IV), when the coating layer on the web is cured, it is also preferable to perform ionizing radiation irradiation performed in an atmosphere of 3% by volume or less in the curing step in a plurality of times.
In this case, it is preferable that the ionizing radiation irradiation is performed at least twice in a reaction chamber having a continuous oxygen concentration of 3% by volume or less. By performing multiple times of ionizing radiation irradiation in the same low oxygen concentration reaction chamber, the reaction time required for curing can be effectively ensured. In particular, when the production speed is increased for high productivity, multiple ionizing radiation irradiations are required to secure the energy of ionizing radiation necessary for the curing reaction, and this is combined with ensuring the reaction time necessary for the curing reaction. The above aspect is effective.
“Consecutive reaction chamber” refers to an embodiment in which ionizing radiation is irradiated at least twice in a reaction chamber having an oxygen concentration of 3% by volume or at least two reaction chambers having an oxygen concentration of 3% by volume or less. There is an embodiment in which the gap is a low oxygen zone having an oxygen concentration of 3% by volume or less. In the latter case, each reaction chamber may have a different oxygen concentration as long as the oxygen concentration is 3% by volume or less.

  In the layer forming method (IV), it is also preferable to perform the curing step while heating the web so that the coating layer surface temperature is 60 ° C. or higher. By performing the curing step while heating, the curing reaction is accelerated by heat, and a film excellent in physical strength and chemical resistance can be formed. In addition, since the polymerization is completed quickly, there is an advantage that the size of the low oxygen zone can be reduced.

  The heating is preferably performed at a coating layer surface temperature of 60 ° C. or higher and 170 ° C. or lower. When the temperature is lower than 60 ° C., the curing by heating is small, while when the temperature exceeds 170 ° C., problems such as deformation of the base material occur. A more preferable temperature is 60 ° C to 100 ° C. Further, the time for which the surface temperature of the coating layer reaches the above temperature is preferably 0.1 second or more and 300 seconds or less from the start of ionizing radiation irradiation, and more preferably 10 seconds or less. If the time for maintaining the temperature of the coating layer surface temperature in the above temperature range is too short, the reaction of the curable composition for forming the film cannot be promoted. There are also problems in manufacturing such as an increase in size.

  The heating method is not particularly limited, but a method of heating a roll to contact the web, a method of spraying heated nitrogen, irradiation with far infrared rays or infrared rays is preferable. A method of heating a rotating metal roll described in Japanese Patent No. 2523574 by flowing a medium such as hot water, steam or oil can also be used. As a heating means, a dielectric heating roll or the like may be used.

(Layer formation method (V))
The layer forming method (V) is a method of continuously producing an optical film having at least one functional layer on a transparent substrate in a web state, and at least one layer laminated on the transparent support, It is formed by the layer formation method including the process of following (1) and (2), It is the method characterized by the above-mentioned.
(1) A step of applying and drying a coating solution containing at least one oxime-based polymerization initiator on a transparent web substrate to form a coating layer, (2) a coating layer on the transparent web substrate, Irradiating ionizing radiation in an atmosphere having an oxygen concentration of 3% by volume or less, and maintaining the transparent web substrate in an atmosphere having an oxygen concentration of 3% by volume or less for 0.5 seconds or more from the start of ionizing radiation irradiation, A step of curing the coating layer.

Hereinafter, the layer forming method (V) will be described.
In the layer forming method (V), at least one of the constituent layers on the transparent web substrate is oxime-based, particularly at least one of the initiators described in the following general formulas (1) to (4) on the transparent web substrate. A step of applying and drying the coating solution to be contained, irradiating with ionizing radiation in an atmosphere having an oxygen concentration of 3% by volume or less, and maintaining the atmosphere having an oxygen concentration of 3% by volume or less for 0.5 seconds or more from the start of ionizing radiation irradiation It is a method of forming by curing.

[In the formula (1), R ¹ is a phenyl group (however, an alkyl group having 1 to 6 carbon atoms, a phenyl group, a halogen atom, —OR ⁸ , —SR ⁹ or —N (R ¹⁰ ) (R ¹¹ ) 1 Or an alkyl group having 1 to 20 carbon atoms (provided that when the alkyl group has 2 to 20 carbon atoms, it has one or more oxygen atoms between main chain carbon atoms, And / or may be substituted with one or more hydroxyl groups), a cycloalkyl group having 5 to 8 carbon atoms, an alkanoyl group having 2 to 20 carbon atoms, a benzoyl group (however, an alkyl group having 1 to 6 carbon atoms, A phenyl group, —OR ⁸ , —SR ⁹ or —N (R ¹⁰ ) (R ¹¹ ), which may be substituted with one or more.), A C 2-12 alkoxycarbonyl group (provided that the carbon of the alkoxy group) When the number is 2 to 11, the alkoxy group is 1 between main chain carbon atoms. Having at least one oxygen atom and / or optionally substituted with one or more hydroxyl groups), a phenoxycarbonyl group (provided that the alkyl group has 1 to 6 carbon atoms, a phenyl group, a halogen atom, -OR ⁸ Or may be substituted with one or more of —N (R ¹⁰ ) (R ¹¹ ).), A cyano group, a nitro group, —CON (R ¹⁰ ) (R ¹¹ ), a haloalkyl group having 1 to 4 carbon atoms, —S (O) _m —R ¹² (wherein R ¹² represents an alkyl group having 1 to 6 carbon atoms, and m is 1 or 2), —S (O) _m —R ¹³ (where R ¹³ Represents an aryl group having 6 to 12 carbon atoms, which may be substituted with an alkyl group having 1 to 12 carbon atoms, and m is 1 or 2.), an alkoxysulfonyl group having 1 to 6 carbon atoms, and a carbon number 6 Represents 10 to 10 aryloxysulfonyl group, or diphenylphosphinoyl group;

R ² is an alkanoyl group having 2 to 12 carbon atoms (however, it may be substituted with one or more of a halogen atom or a cyano group), and having 4 to 6 carbon atoms whose double bond is not conjugated with a carbonyl group. Substituted with one or more of an alkenoyl group, a benzoyl group (wherein the alkyl group has 1 to 6 carbon atoms, a halogen atom, a cyano group, —OR ⁸ , —SR ⁹ or —N (R ¹⁰ ) (R ¹¹ )) 2) an alkoxycarbonyl group having 2 to 6 carbon atoms, or a phenoxycarbonyl group (which may be substituted with one or more alkyl groups having 1 to 6 carbon atoms or halogen atoms);

R ³ , R ⁴ , R ⁵ , R ⁶ and R ⁷ are each independently a hydrogen atom, a halogen atom, an alkyl group having 1 to 12 carbon atoms, a cyclopentyl group, a cyclohexyl group, or a phenyl group (provided that —OR ⁸ , -SR ⁹ or -N (R ¹⁰⁾ may be substituted with (R ¹¹⁾ 1 or more.), a benzyl group, a benzoyl group, an alkanoyl group having 2 to 12 carbon atoms, alkoxy of 2 to 12 carbon atoms A carbonyl group (provided that when the alkoxy group has 2 to 11 carbon atoms, the alkoxy group may have one or more oxygen atoms between main chain carbon atoms and / or be substituted with one or more hydroxyl groups) Phenoxycarbonyl group, —OR ⁸ (wherein R ⁸ may form a 5-membered ring or a 6-membered ring together with one of the carbon atoms in the phenyl ring or a substituent to the phenyl ring). Good), -SR ⁹ ( However, R ⁹ may form a 5-membered ring or a 6-membered ring together with one of the carbon atoms in the phenyl ring or in the substituent to the phenyl ring.), —S (O) R ⁹ (However, R ⁹ may form a 5-membered ring or a 6-membered ring together with one of the carbon atoms in the phenyl ring or in the substituent to the phenyl ring), —SO ₂ R ⁹ ( R ⁹ may form a 5-membered ring or a 6-membered ring together with one of the carbon atoms in the phenyl ring or in the substituent to the phenyl ring.), Or —N (R ¹⁰ ) (R ¹¹ ) (However, R ¹⁰ and / or R ¹¹ may form a 5-membered ring or a 6-membered ring together with one of the carbon atoms in the phenyl ring or in the substituent to the phenyl ring. .) indicates, and ^{R 3, R 4, R 5} , at least one -OR ⁸ of and R ⁶ and R ^7, -SR ⁹ or -N R ¹⁰⁾ be a (R ^11);

R ⁸ is a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, a substituted alkyl group having 2 to 6 carbon atoms {provided that the substituent is a hydroxyl group, a mercapto group, a cyano group, an alkoxy group having 1 to 4 carbon atoms, An alkenyloxy group having 3 to 6 carbon atoms, a 2-cyanoethoxy group, a 2- (alkoxycarbonyl) ethoxy group having 4 to 7 carbon atoms, an alkylcarbonyloxy group having 2 to 5 carbon atoms, a phenylcarbonyloxy group, a carboxyl group, or It consists of one or more alkoxycarbonyl groups having 2 to 5 carbon atoms. }, An alkyl group having 2 to 6 carbon atoms having one or more oxygen atoms between main chain carbon atoms, an alkanoyl group having 2 to 8 carbon atoms, — (CH ₂ CH ₂ O) _n H (where n is 1) An alkenyl group having 3 to 12 carbon atoms, an alkenoyl group having 3 to 6 carbon atoms, a cyclohexyl group, a phenyl group (however, a halogen atom, an alkyl group having 1 to 12 carbon atoms, or a carbon number of 1). To 4 alkoxy groups), a phenylalkyl group having 7 to 9 carbon atoms, —Si (R ¹⁴ ) _r (R ¹⁵ ) _3-r (wherein R ¹⁴ has 1 to 8 carbon atoms) Represents an alkyl group, R ¹⁵ represents a phenyl group, and r is an integer of 1 to 3).

Group represented by the following formula

Or a group represented by the following formula

Indicates;
R ⁹ is a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, an alkenyl group having 3 to 12 carbon atoms, a cyclohexyl group, a substituted alkyl group having 2 to 6 carbon atoms {provided that the substituent includes a hydroxyl group, a mercapto group, Cyano group, alkoxy group having 1 to 4 carbon atoms, alkenyloxy group having 3 to 6 carbon atoms, 2-cyanoethoxy group, 2- (alkoxycarbonyl) ethoxy group having 4 to 7 carbon atoms, alkyl having 2 to 5 carbon atoms It consists of one or more of a carbonyloxy group, a phenylcarbonyloxy group, a carboxyl group or an alkoxycarbonyl group having 2 to 5 carbon atoms. }, An alkyl group having 2 to 12 carbon atoms having at least one oxygen atom or sulfur atom between main chain carbon atoms, a phenyl group (however, a halogen atom, an alkyl group having 1 to 12 carbon atoms or a carbon number of 1 to 4) A phenylalkyl group having 7 to 9 carbon atoms,

Group represented by the following formula

Or a group represented by the following formula

Indicates;
R ¹⁰ and R ¹¹ are each independently a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, a hydroxyalkyl group having 2 to 4 carbon atoms, an alkoxyalkyl group having 2 to 10 carbon atoms, or an alkenyl group having 3 to 5 carbon atoms. , A cycloalkyl group having 5 to 12 carbon atoms, a phenylalkyl group having 7 to 9 carbon atoms, a phenyl group (provided that it is substituted with one or more of an alkyl group having 1 to 12 carbon atoms or an alkoxy group having 1 to 4 carbon atoms) Or an alkanoyl group having 2 to 3 carbon atoms, an alkenoyl group having 3 to 6 carbon atoms, or a benzoyl group, or an alkylene group having 2 to 6 carbon atoms in combination of R ¹⁰ and R ¹¹ ( However, the main chain carbon atoms between the one or more oxygen atoms or -NR ⁸ - or having, and / or a hydroxyl group, an alkoxy group having 1 to 4 carbon atoms, alkanoyloxy group or Benzoiruoki C2-4 May be substituted with one or more groups.) Or show, or when R ¹⁰ is a hydrogen atom, R ¹¹ is

Group represented by the following formula

Or a group represented by the following formula

Indicates;
R ¹⁶ represents an alkoxycarbonyl group having 2 to 12 carbon atoms (provided that when the alkoxy group has 2 to 11 carbon atoms, the alkoxy group has one or more oxygen atoms between main chain carbon atoms, and / or May be substituted with one or more hydroxyl groups), a phenoxycarbonyl group (however, an alkyl group having 1 to 6 carbon atoms, a halogen atom, a phenyl group, —OR ⁸ or —N (R ¹⁰ ) (R ¹¹ )). 1 or more may be substituted.), A cycloalkyl group having 5 to 8 carbon atoms, —CON (R ¹⁰ ) (R ¹¹ ), a cyano group, a substituted phenyl group (provided that the substituent is —SR ⁹ ), or an alkyl group having 1 to 12 carbon atoms (provided that it is substituted with one or more of a halogen atom, a hydroxyl group, —OR ² , a phenyl group, a halogenated phenyl group or —SR ⁹ ), and / or Or oxygen between main chain carbon atoms One or more of atoms or —NH (CO) — may be present);

M ¹ represents a direct bond or —R ¹⁷ —O—; M ² represents a direct bond or —R ¹⁷ —S—; M ³ represents a direct bond, a piperazino group or —R ¹⁷ —NH—; R ¹⁷ Is an alkylene group having 1 to 12 carbon atoms (however, when the carbon number is 2 to 12, it may have 1 to 5 oxygen atoms, sulfur atoms, or —NR ¹⁰ — between main chain carbon atoms). ). ]

In [Equation ^{(2), R 2, R} 3, R 4, R 5, R 6 and R ⁷ each R ^2, R ³ of formula ^{(1), R 4, R} 5, R 6 and R ⁷ as defined M is an alkylene group having 1 to 12 carbon atoms, a cyclohexylene group, a phenylene group, —COO—R ¹⁸ —OCO—, —COO— (CH ₂ CH ₂ O) _n —CO— (where n is 1) Represents an integer of ˜20), or —CO—R ¹⁸ —CO—;
R ¹⁸ represents an alkylene group having 2 to 12 carbon atoms. ]

[In the formula (3), R ² is the same meaning as R ² in formula (1); if R ¹⁹ is an alkoxycarbonyl group having 2 to 12 carbon atoms (provided that the carbon number of the alkoxy group of 2 to 11, the The alkoxy group has one or more oxygen atoms between main chain carbon atoms and / or may be substituted with one or more hydroxyl groups), a phenoxycarbonyl group (however, an alkyl group having 1 to 6 carbon atoms) , A halogen atom, a phenyl group, optionally substituted with one or more of —OR ⁸ or —N (R ¹⁰ ) (R ¹¹ ), a cycloalkyl group having 5 to 8 carbon atoms, —CON (R ¹⁰ ) (R ¹¹ ), a cyano group, or a substituted phenyl group (wherein the substituent is —SR ⁹ ), or a carbon atom in the phenyl ring having R ²⁰ , R ²¹ and R ²² combine to form a a through 5-membered ring or 6-membered cyclic group R ⁹ At best, or R ^20, when at least one of R ²¹ and R ²² is -SR ^9, alkyl group {where 1 to 12 carbon atoms, when the number of carbon atoms of 2 to 12, between the main chain carbon atoms One or more of an oxygen atom or —NH (CO) — and / or a halogen atom, a hydroxyl group, —OR ² , a phenyl group, a halogenated phenyl group or a substituted phenyl group (provided that the substituent is —SR ⁹ 1) or more of them may be substituted. };

R ²⁰ , R ²¹ and R ²² are each independently a hydrogen atom, a halogen atom, an alkyl group having 1 to 12 carbon atoms, a cyclopentyl group, a cyclohexyl group, a phenyl group (provided that —OR ⁸ , —SR ⁹ or —N ( R ¹⁰ ) (may be substituted with one or more of (R ¹¹ ))), a benzyl group, a benzoyl group, an alkanoyl group having 2 to 12 carbon atoms, an alkoxycarbonyl group having 2 to 12 carbon atoms (provided that the alkoxy group When the number of carbon atoms is 2 to 11, the alkoxy group may have one or more oxygen atoms between main chain carbon atoms and / or may be substituted with one or more hydroxyl groups), a phenoxycarbonyl group, -OR ⁸ (where, R ⁸ together with one of the carbon atoms in the substituent to or phenyl ring in the phenyl ring, may form a 5- membered ring or 6-membered ring.), - SR ⁹ (However, R ⁹ is phenylene Together with one of the carbon atoms in the substituent to or phenyl ring in the ring, may form a 5- membered ring or 6-membered ring), -. S (O) R 9, -SO 2 R 9 Or —N (R ¹⁰ ) (R ¹¹ ) (wherein R ¹⁰ and / or R ¹¹ together with one of the carbon atoms in the phenyl ring or in the substituent to the phenyl ring, And at least one of R ²⁰ , R ²¹ and R ²² is —OR ⁸ , —SR ⁹ or —N (R ¹⁰ ) (R ¹¹ ); ^8, R ^9, R ¹⁰ and R ¹¹ are the same with each R ^8, R ^9, R ¹⁰ and R ¹¹ of formula (1). ]

[In the formula (4), R ² and M is R ² and M as defined in formula (2), respectively formula (1); R ^20, R ²¹ and R ²² each R ²⁰ of formula (3), Synonymous with R ²¹ and R ²² . ]

Although there is no restriction | limiting in particular in the usage-amount of an initiator, It is preferable to use in 0.1-15 mass parts with respect to 100 mass parts of polyfunctional monomers, More preferably, it is 1-10 mass parts. In addition, the initiators (1) to (4) may be used in a plurality of types, or may be used in combination with other radical polymerization initiators or photosensitizers.
Specific examples of the compound include compounds described in JP-A No. 2000-80068 or JP-A No. 2001-264530, but are not particularly limited thereto.
Examples of the compounds described in JP 2000-80068 A are shown below. (Exemplary compounds 1 to 21)

In the layer forming method (V), after applying and drying the coating solution containing the initiator on the web substrate, the ionizing radiation is irradiated in an atmosphere having an oxygen concentration of 3% by volume or less and the ionizing radiation irradiation is started from 0. Curing is performed by maintaining the atmosphere in an oxygen concentration of 3% by volume or less for 5 seconds or more. By supplying inert gas to the ionizing radiation reaction chamber and making it slightly blown to the web entrance side of the reaction chamber, it is possible to effectively reduce the oxygen concentration in the reaction chamber by eliminating the carry air accompanying the web transfer, It is possible to efficiently reduce the substantial oxygen concentration on the pole surface where the inhibition of curing by oxygen is large. The direction of the inert gas flow on the web entrance side of the irradiation chamber can be controlled by adjusting the balance between supply and exhaust of the irradiation chamber.
Blowing an inert gas directly onto the web surface is also preferably used as a method for removing carried air.
In particular, it is preferable that the low refractive index layer which is the outermost layer and has a small film thickness is cured by this method.

  Further, by providing a front chamber in front of the reaction chamber and excluding oxygen on the web surface in advance, the curing can proceed more efficiently. Further, the side surface constituting the web entrance side of the ionizing radiation reaction chamber or the front chamber is preferably 0.2 to 15 mm in gap with the web surface in order to use the inert gas efficiently, more preferably, 0.1%. The thickness is preferably 2 to 10 mm, and most preferably 0.2 to 5 mm. However, in order to continuously manufacture the web, it is necessary to join and connect the webs, and a method of sticking with a joining tape or the like is widely used for joining. For this reason, if the gap between the entrance surface of the ionizing radiation reaction chamber or the front chamber and the web is too narrow, there arises a problem that the joining member such as the joining tape is caught. For this reason, in order to narrow the gap, it is preferable to make at least a part of the entrance surface of the ionizing radiation reaction chamber or the front chamber movable, and to widen the gap by the junction thickness when the junction enters. In order to realize this, the entrance surface of the ionizing radiation reaction chamber or the front chamber is made movable in the forward and backward direction, and when the joint passes, the gap is moved back and forth to widen the gap, The chamber entrance surface can be moved vertically with respect to the web surface, and when the joint passes, it can be moved up and down to widen the gap (see Example E-14, FIGS. 1 to 4). .

The oxygen concentration in the atmosphere when irradiating with ionizing radiation is 3% by volume or less, preferably 1% by volume or less, and more preferably 0.1% by volume or less. In order to reduce the oxygen concentration more than necessary, a large amount of inert gas such as nitrogen is required, which is not preferable from the viewpoint of production cost. As a means for reducing the oxygen concentration, it is preferable to replace the atmosphere (nitrogen concentration of about 79% by volume, oxygen concentration of about 21% by volume) with another inert gas, particularly preferably with nitrogen (nitrogen purge). It is.
In the layer forming method (V), at least one layer laminated on the transparent substrate is irradiated with ionizing radiation in an atmosphere having an oxygen concentration of 3% by volume or less, and 0.5 seconds or more from the start of ionizing radiation irradiation, and the oxygen concentration is 3 volumes. % Atmosphere is maintained. 0.7 seconds or more and 60 seconds or less are preferable, and 0.7 seconds or more and 10 seconds or less are more preferable. If it is 0.5 seconds or less, the curing reaction cannot be completed and sufficient curing cannot be performed. Also, maintaining low oxygen conditions for a long time is not preferable because the equipment becomes large and a large amount of inert gas is required.
In the layer forming method (V), at least one layer laminated on the transparent substrate can be cured by ionizing radiation multiple times. In this case, it is preferable that at least two ionizing radiations are performed in a continuous reaction chamber in which the oxygen concentration does not exceed 3% by volume. By performing multiple times of ionizing radiation irradiation in the same low oxygen concentration reaction chamber, the reaction time required for curing can be effectively ensured.
In particular, when the production rate is increased for high productivity, multiple ionizing radiation irradiations are necessary to ensure the energy of ionizing radiation necessary for the curing reaction, and this is combined with ensuring the reaction time necessary for the curing reaction. The above aspect is effective.

In the layer formation method (V), it is preferable that at least one layer laminated on the transparent substrate is cured by a process of heating to a film surface temperature of 60 ° C. or higher and irradiating with ionizing radiation in an atmosphere having an oxygen concentration of 3% by volume or lower. . It is also preferable to heat in an atmosphere having an oxygen concentration of 3% by volume or less simultaneously and / or continuously with ionizing radiation irradiation. The curing reaction is accelerated by heat, and a film having excellent physical strength and chemical resistance can be formed.
It is preferable that the film surface is heated at 60 ° C. or higher and 170 ° C. or lower. At 60 ° C. or lower, there is little curing by heating, and at 170 ° C. or higher, problems such as deformation of the substrate occur. Furthermore, this preferable temperature is 60 degreeC-100 degreeC. The film surface refers to the film surface temperature of the layer to be cured. Further, the time for the film to reach the temperature is preferably 0.1 seconds or more and 300 seconds or less, more preferably 10 seconds or less from the start of UV irradiation. If the time for maintaining the temperature of the film surface in the above temperature range is too short, the reaction of the curable composition that forms the film cannot be accelerated, and conversely, if it is too long, the optical performance of the film deteriorates and the equipment is large. Manufacturing problems such as

  There is no particular limitation on the heating method, but a method of heating a roll to contact the film, a method of spraying heated nitrogen, irradiation with far infrared rays or infrared rays is preferable. A method of heating a rotating metal roll described in Japanese Patent No. 2523574 by flowing a medium such as hot water, steam or oil can also be used. As a heating means, a dielectric heating roll or the like may be used.

[Ionizing radiation species]
The ionizing radiation species in the present invention is not particularly limited, and is appropriately selected from ultraviolet rays, electron beams, near ultraviolet rays, visible light, near infrared rays, infrared rays, X-rays, and the like depending on the type of curable composition forming a film. You can choose. In the present invention, irradiation with ultraviolet rays is preferred. Ultraviolet curing is preferred because the polymerization rate is fast and the equipment can be made compact, and there are abundant and low-priced compound types that can be selected.
In the case of ultraviolet rays, an ultra-high pressure mercury lamp, a high pressure mercury lamp, a low pressure mercury lamp, a carbon arc, a xenon arc, a metal halide lamp, etc. can be used. In the case of electron beam irradiation, energy of 50 to 1000 keV emitted from various electron beam accelerators such as Cockloft Walton type, bandegraph type, resonant transformation type, insulated core transformer type, linear type, dynamitron type, and high frequency type. An electron beam having the following is used.

[Film-forming binder]
In the present invention, it is possible to use an ionizing radiation curable compound, preferably a compound having an ethylenically unsaturated group, as the main film forming binder component of the film forming composition. It is preferable in terms of properties. The main film-forming binder component refers to a component that occupies 10% by mass or more and 100% by mass or less of the film-forming component excluding inorganic particles. Preferably, they are 20 mass% or more and 100 mass% or less, More preferably, they are 30 mass% or more and 95% or less.
In the present specification, the “ionizing radiation curable compound” may be any compound that is cured by irradiation with ionizing radiation, and includes any of monomers, oligomers, and polymers.
The main film-forming binder is preferably a polymer having a saturated hydrocarbon chain or a polyether chain as the main chain, and more preferably a polymer having a saturated hydrocarbon chain as the main chain. Furthermore, these polymers preferably have a crosslinked structure.
As the binder polymer having a saturated hydrocarbon chain as the main chain and having a crosslinked structure, a (co) polymer of monomers having two or more ethylenically unsaturated groups is preferable.
Furthermore, in the case of a high refractive index, the monomer structure may contain at least one atom selected from an aromatic ring, a halogen atom other than fluorine, a sulfur atom, a phosphorus atom, and a nitrogen atom. preferable.

Examples of the monomer having two or more ethylenically unsaturated groups include esters of polyhydric alcohol and (meth) acrylic acid (eg, ethylene glycol di (meth) acrylate, 1,4-cyclohexanediacrylate, pentaerythritol tetra ( (Meth) acrylate), pentaerythritol tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolethane tri (meth) acrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, di Pentaerythritol hexa (meth) acrylate, pentaerythritol hexa (meth) acrylate, 1,2,3-cyclohexanetetramethacrylate, polyurethane polyacrylate, polyester poly Acrylate), vinylbenzene and its derivatives (eg, 1,4-divinylbenzene, 4-vinylbenzoic acid-2-acryloylethyl ester, 1,4-divinylcyclohexanone), vinylsulfone (eg, divinylsulfone), acrylamide (eg, , Methylenebisacrylamide) and methacrylamide.
Two or more of these monomers may be used in combination. In the present specification, “(meth) acrylate”, “(meth) acryloyl”, and “(meth) acrylic acid” are “acrylate or methacrylate”, “acryloyl or methacryloyl”, “acrylic acid or methacrylic acid”, respectively. ".

  Furthermore, specific examples of the high refractive index monomer include bis (4-methacryloylthiophenyl) sulfide, vinyl naphthalene, vinyl phenyl sulfide, 4-methacryloxyphenyl-4′-methoxyphenyl thioether, and the like. Two or more of these monomers may be used in combination.

  Polymerization of the monomer having an ethylenically unsaturated group can be performed by irradiation with ionizing radiation or heating in the presence of a photo radical initiator or a thermal radical initiator.

Photo radical polymerization initiators include acetophenones, benzoins, benzophenones, phosphine oxides, ketals, anthraquinones, thioxanthones, azo compounds, peroxides, 2,3-dialkyldione compounds, disulfide compounds , Fluoroamine compounds, aromatic sulfoniums and the like.
Examples of acetophenones include 2,2-diethoxyacetophenone, p-dimethylacetophenone, 1-hydroxy-dimethylphenyl ketone, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-4-methylthio-2-morpholinopropiophenone, 2-Benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone is included. Also included are 2,2-dimethoxyacetophenone, 1-hydroxy-dimethyl-p-isopropylphenylketone, 4-phenoxydichloroacetophenone, 4-t-butyl-dichloroacetophenone.

Examples of benzoins include benzoin benzene sulfonate, benzoin toluene sulfonate, benzoin methyl ether, benzoin ethyl ether and benzoin isopropyl ether. Also included are benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, and benzyldimethyl ketal.
Examples of the benzophenones include benzophenone, 2,4-dichlorobenzophenone, 4,4-dichlorobenzophenone and p-chlorobenzophenone, hydroxybenzophenone. Also included are 4-benzoyl-4′-methyldiphenyl sulfide, 4,4′-dimethylaminobenzophenone (Michler ketone), 3,3 ′, 4,4′-tetra (t-butylperoxycarbonyl) benzophenone, and the like.
Examples of phosphine oxides include 2,4,6-trimethylbenzoyldiphenylphosphine oxide.

Examples of the photo radical polymerization initiator include lophine dimers, onium salts, borate salts, active esters, active halogens, inorganic complexes, and coumarins.
Examples of active esters include 1,2-octanedione, 1- [4- (phenylthio)-, 2- (O-benzoyloxime)], sulfonic acid esters, cyclic active ester compounds, and the like. Specifically, Examples 1 to 21 described in JP-A 2000-80068 are particularly preferable.
Examples of the onium salts include aromatic diazonium salts, aromatic iodonium salts, and aromatic sulfonium salts.
Examples of borate salts include ion complexes with cationic dyes.

  Examples of active halogens are S-triazine and oxathiazole compounds. 2- (p-methoxyphenyl) -4,6-bis (trichloromethyl) -s-triazine, 2- (p-methoxyphenyl) ) -4,6-bis (trichloromethyl) -s-triazine, 2- (p-styrylphenyl) -4,6-bis (trichloromethyl) -s-triazine, 2- (3-Br-4-di ( Ethyl acetate) amino) phenyl) -4,6-bis (trichloromethyl) -s-triazine, 2-trihalomethyl-5- (p-methoxyphenyl) -1,3,4-oxadiazole. Specifically, p. 14 to p. 30 in JP-A-58-15503, p. 6 to p. 10 in JP-A 55-77742, No. 1 to No. 8 in p. 287 in JP-B 60-27673, Compounds such as Nos. 1 to 17 of p443 to p444 of No. 60-239736 and Nos. 1 to 19 of US-4701399 are particularly preferable.

Examples of inorganic complexes include bis (η ⁵ -2,4-cyclopentadien-1-yl) -bis (2,6-difluoro-3- (1H-pyrrol-1-yl) -phenyl) titanium.
Examples of coumarins include 3-ketocoumarin.
These initiators may be used alone or in combination.
“Latest UV Curing Technology”, Technical Information Association, 1991, p. 159 and “UV curing system” written by Kayo Kiyomi, 1989, published by General Technology Center, p. 65-148, are useful for the present invention.

  Commercially available photocleavable photoradical polymerization initiators include Irgacure (651, 184, 819, 907, 1870 (CGI-403 / Irg184 = 7/3 mixed initiator, 500) manufactured by Ciba Specialty Chemicals Co., Ltd. , 369, 1173, 2959, 4265, 4263, etc.), OXE01), etc., and Kayacure (DETX-S, BP-100, BDMK, CTX, BMS, 2-EAQ, ABQ, CPTX, EPD, manufactured by Nippon Kayaku Co., Ltd. , ITX, QTX, BTC, MCA, etc.), Esacure (KIP100F, KB1, EB3, BP, X33, KT046, KT37, KIP150, TZT) manufactured by Sartomer, and combinations thereof are preferable examples.

The photo radical initiator is preferably used in the range of 0.1 to 15 parts by mass, more preferably in the range of 1 to 10 parts by mass with respect to 100 parts by mass of the polyfunctional monomer.
In addition to the photopolymerization initiator, a photosensitizer may be used. Specific examples of the photosensitizer include n-butylamine, triethylamine, tri-n-butylphosphine, Michler's ketone and thioxanthone.
Furthermore, one or more auxiliary agents such as an azide compound, a thiourea compound, and a mercapto compound may be used in combination.
Examples of commercially available photosensitizers include Kayacure (DMBI, EPA) manufactured by Nippon Kayaku Co., Ltd.

As the thermal radical initiator, organic or inorganic peroxides, organic azo, diazo compounds, and the like can be used.
Specifically, benzoyl peroxide, halogen benzoyl peroxide, lauroyl peroxide, acetyl peroxide, dibutyl peroxide, cumene hydroperoxide, butyl hydroperoxide as organic peroxides, hydrogen peroxide, peroxides as inorganic peroxides. 2,2′-azobis (isobutyronitrile), 2,2′-azobis (propionitrile), 1,1′-azobis (cyclohexanecarbonitrile), etc. as diazo compounds such as ammonium sulfate and potassium persulfate Examples of the compound include diazoaminobenzene and p-nitrobenzenediazonium.

  In the present invention, a polymer having a polyether as a main chain can also be used, and a ring-opening polymer of a polyfunctional epoxy compound is preferable. The ring-opening polymerization of the polyfunctional epoxy compound can be performed by irradiation with ionizing radiation or heating in the presence of a photoacid generator or a thermal acid generator. Known photoacid generators and thermal acid generators can be used.

Instead of or in addition to a monomer having two or more ethylenically unsaturated groups, a monomer having a crosslinkable functional group is used to introduce a crosslinkable functional group into the polymer, and by reaction of this crosslinkable functional group, A crosslinked structure may be introduced into the binder polymer.
Examples of the crosslinkable functional group include isocyanate group, epoxy group, aziridine group, oxazoline group, aldehyde group, carbonyl group, hydrazine group, carboxyl group, methylol group and active methylene group. Vinylsulfonic acid, acid anhydride, cyanoacrylate derivative, melamine, etherified methylol, ester and urethane, and metal alkoxide such as tetramethoxysilane can also be used as a monomer for introducing a crosslinked structure. A functional group that exhibits crosslinkability as a result of the decomposition reaction, such as a block isocyanate group, may be used. That is, in the present invention, the crosslinkable functional group may not react immediately but may exhibit reactivity as a result of decomposition.
These binder polymers having a crosslinkable functional group can form a crosslinked structure by heating after coating.
In this invention, it is not limited to said ionizing radiation curable compound, A curable composition can be selected suitably for every functional layer. Hereinafter, each functional layer will be described in detail.

[Material for low refractive index layer]
The low refractive index layer is preferably formed by a cured film of a copolymer having a repeating unit derived from a fluorine-containing vinyl monomer and a repeating unit having a (meth) acryloyl group in the side chain as essential constituent components. The copolymer-derived component preferably occupies 60% by mass or more, more preferably 70% by mass or more, and particularly preferably 80% by mass or more. From the viewpoint of achieving both low refractive index and film hardness, a curing agent such as polyfunctional (meth) acrylate is also preferably used in an addition amount within a range that does not impair the compatibility.
In addition, compounds described in JP-A-11-228631 are also preferably used.

The refractive index of the low refractive index layer is preferably 1.20 to 1.46, more preferably 1.25 to 1.46, and particularly preferably 1.30 to 1.46.
The thickness of the low refractive index layer is preferably 200 nm or less, more preferably 50 to 200 nm, and even more preferably 70 to 100 nm. The haze of the low refractive index layer is preferably 3% or less, more preferably 2% or less, and most preferably 1% or less. The specific strength of the low refractive index layer is preferably H or higher, more preferably 2H or higher, and most preferably 3H or higher in a pencil hardness test under a 500 g load.
Further, in order to improve the antifouling performance of the antireflection film, it is preferable that the contact angle of the surface with respect to water is 90 ° or more. More preferably, it is 95 ° or more, and particularly preferably 100 ° or more.

The copolymer preferably used for the low refractive index layer of the present invention will be described below.
Examples of the fluorine-containing vinyl monomer include fluoroolefins (for example, fluoroethylene, vinylidene fluoride, tetrafluoroethylene, hexafluoropropylene, etc.), (meth) acrylic acid moieties or fully fluorinated alkyl ester derivatives (for example, biscoat 6FM (trade name) , Osaka Organic Chemical Industry Co., Ltd.), R-2020 (trade name, manufactured by Daikin Industries, Ltd.), etc.), and fully or partially fluorinated vinyl ethers, and the like, preferably perfluoroolefins, Hexafluoropropylene is particularly preferred from the viewpoints of refractive index, solubility, transparency, availability and the like. Increasing the composition ratio of these fluorine-containing vinyl monomers can lower the refractive index but lowers the film strength. In the present invention, it is preferable to introduce the fluorine-containing vinyl monomer so that the fluorine content of the copolymer is 20 to 60% by mass, more preferably 25 to 55% by mass, and particularly preferably 30 to 50% by mass. This is a case of mass%.

  The copolymer of the present invention preferably has a repeating unit having a (meth) acryloyl group in the side chain as an essential component. If the composition ratio of these (meth) acryloyl group-containing repeating units is increased, the film strength is improved, but the refractive index is also increased. Generally, the (meth) acryloyl group-containing repeating unit preferably accounts for 5 to 90% by mass, more preferably 30 to 70% by mass, although it varies depending on the type of repeating unit derived from the fluorine-containing vinyl monomer. It is particularly preferred to account for ~ 60% by weight.

  In the copolymer useful for the present invention, in addition to the repeating unit derived from the above-mentioned fluorine-containing vinyl monomer and the repeating unit having a (meth) acryloyl group in the side chain, it contributes to adhesion to the substrate and Tg of the polymer (film hardness). And other vinyl monomers can be copolymerized as appropriate from various viewpoints such as solubility in a solvent, transparency, slipperiness, dust resistance and antifouling properties. A plurality of these vinyl monomers may be combined depending on the purpose, and are preferably introduced in the range of 0 to 65 mol% in the copolymer in total, and in the range of 0 to 40 mol%. More preferably, it is particularly preferably in the range of 0 to 30 mol%.

  The vinyl monomer unit that can be used in combination is not particularly limited. For example, olefins (ethylene, propylene, isoprene, vinyl chloride, vinylidene chloride, etc.), acrylic esters (methyl acrylate, ethyl acrylate, -2-ethylhexyl acrylate) , 2-hydroxyethyl acrylate), methacrylic acid esters (methyl methacrylate, ethyl methacrylate, butyl methacrylate, 2-hydroxyethyl methacrylate, etc.), styrene derivatives (styrene, p-hydroxymethylstyrene, p- Methoxystyrene, etc.), vinyl ethers (methyl vinyl ether, ethyl vinyl ether, cyclohexyl vinyl ether, hydroxyethyl vinyl ether, hydroxybutyl vinyl ether, etc.), vinyl esters (vinyl acetate, vinyl propionate, Vinyl cinnamate, etc.), unsaturated carboxylic acids (acrylic acid, methacrylic acid, crotonic acid, maleic acid, itaconic acid, etc.), acrylamides (N, N-dimethylacrylamide, N-tert-butylacrylamide, N-cyclohexylacrylamide, etc.) ), Methacrylamides (N, N-dimethylmethacrylamide), acrylonitrile and the like.

  In the present invention, a fluorine-containing polymer represented by the following general formula 1 is preferably used.

In General Formula 1, L represents a linking group having 1 to 10 carbon atoms, more preferably a linking group having 1 to 6 carbon atoms, particularly preferably a linking group having 2 to 4 carbon atoms, It may have a branched structure, may have a ring structure, and may have a heteroatom selected from O, N, and S.
Preferred examples include * — (CH ₂ ) ₂ —O — **, * — (CH ₂ ) ₂ —NH — **, * — (CH ₂ ) ₄ —O — **, * — (CH ₂ ). ₆ —O — **, — (CH ₂ ) ₂ —O— (CH ₂ ) ₂ —O — **, * —CONH— (CH ₂ ) ₃ —O — **, * —CH ₂ CH (OH) _{CH 2 -O - **, * -CH} 2 CH 2 OCONH (CH 2) 3 -O - ** (* represents a linking site on the polymer main chain side and ** (meth) linking site acryloyl group side And the like. m represents 0 or 1;

  In general formula 1, X represents a hydrogen atom or a methyl group. From the viewpoint of curing reactivity, a hydrogen atom is more preferable.

  In the general formula 1, A represents a repeating unit derived from an arbitrary vinyl monomer, and is not particularly limited as long as it is a constituent component of a monomer copolymerizable with hexafluoropropylene. Tg (contributes to film hardness), solubility in solvents, transparency, slipperiness, dust / antifouling properties, etc., can be selected as appropriate, depending on the purpose, depending on the single or multiple vinyl monomers It may be configured.

  Preferred examples of the vinyl monomer include methyl vinyl ether, ethyl vinyl ether, t-butyl vinyl ether, cyclohexyl vinyl ether, isopropyl vinyl ether, hydroxyethyl vinyl ether, hydroxybutyl vinyl ether, glycidyl vinyl ether, allyl vinyl ether and other vinyl ethers, vinyl acetate, propionic acid Vinyl esters such as vinyl and vinyl butyrate, methyl (meth) acrylate, ethyl (meth) acrylate, hydroxyethyl (meth) acrylate, glycidyl methacrylate, allyl (meth) acrylate, (meth) acryloyloxypropyltrimethoxysilane, etc. (Meth) acrylates, styrene, styrene derivatives such as p-hydroxymethylstyrene, crotonic acid, malein , There may be mentioned unsaturated carboxylic acids and derivatives thereof such as itaconic acid, more preferably a vinyl ether derivative, vinyl ester derivatives, particularly preferably a vinyl ether derivative.

  x, y, and z represent mol% of each constituent component, and represent values satisfying 30 ≦ x ≦ 60, 5 ≦ y ≦ 70, and 0 ≦ z ≦ 65. Preferably, 35 ≦ x ≦ 55, 30 ≦ y ≦ 60, and 0 ≦ z ≦ 20, and particularly preferably 40 ≦ x ≦ 55, 40 ≦ y ≦ 55, and 0 ≦ z ≦ 10.

  As a particularly preferred embodiment of the copolymer used in the present invention, general formula 2 can be mentioned.

In general formula 2, X, x, and y have the same meaning as in general formula 1, and the preferred ranges are also the same.
n represents an integer of 2 ≦ n ≦ 10, preferably 2 ≦ n ≦ 6, and particularly preferably 2 ≦ n ≦ 4.
B represents a unit of a repeating unit derived from an arbitrary vinyl monomer, and may be composed of a single composition or a plurality of compositions. As an example, what was demonstrated as an example of A in the said General formula 1 is applicable.
z1 and z2 represent mol% of each repeating unit, and represent values satisfying 0 ≦ z1 ≦ 65 and 0 ≦ z2 ≦ 65. It is preferable that 0 ≦ z1 ≦ 30 and 0 ≦ z2 ≦ 10 respectively, and it is particularly preferable that 0 ≦ z1 ≦ 10 and 0 ≦ z2 ≦ 5.

  The copolymer represented by the general formula 1 or 2 can be synthesized, for example, by introducing a (meth) acryloyl group into a copolymer comprising a hexafluoropropylene component and a hydroxyalkyl vinyl ether component.

  Although the preferable example of a useful copolymer in the low refractive index layer of this invention is shown below, this invention is not limited to these.

  The copolymer used for this invention is compoundable by the method as described in Unexamined-Japanese-Patent No. 2004-45462. The copolymer used in the present invention was synthesized by synthesizing precursors such as a hydroxyl group-containing polymer by various polymerization methods other than those described above, for example, solution polymerization, precipitation polymerization, suspension polymerization, bulk polymerization, and emulsion polymerization. Then, it can also carry out by introduce | transducing a (meth) acryloyl group by the said polymer reaction. The polymerization reaction can be performed by a known operation such as a batch system, a semi-continuous system, or a continuous system.

The polymerization initiation method includes a method using a radical initiator, a method of irradiating light or radiation, a method of irradiating ionizing radiation, and the like.
These polymerization methods and polymerization initiation methods are, for example, the revised version of Tsuruta Junji “Polymer Synthesis Method” (published by Nikkan Kogyo Shimbun, 1971), Takatsu Otsu, Masato Kinoshita, “Experimental Methods for Polymer Synthesis” It is described on pages 124-154, published in 1972.

  Among the above polymerization methods, a solution polymerization method using a radical initiator is particularly preferable. Examples of the solvent used in the solution polymerization method include ethyl acetate, butyl acetate, acetone, methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK), cyclohexanone, tetrahydrofuran, dioxane, N, N-dimethylformamide, N, N-dimethylacetamide, Benzene, toluene, acetonitrile, methylene chloride, chloroform, dichloroethane, methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, or a mixture of two or more kinds of organic solvents may be used. A mixed solvent may be used.

  The polymerization temperature needs to be set in relation to the molecular weight of the polymer to be produced, the type of initiator, etc., and can be from 0 ° C. or lower to 100 ° C. or higher, but it is preferable to carry out the polymerization in the range of 50 to 100 ° C.

  The reaction pressure can be selected as appropriate, but usually 1 to 100 kPa, particularly about 1 to 30 kPa is desirable. The reaction time is about 5 to 30 hours.

  As the reprecipitation solvent for the obtained polymer, isopropanol, hexane, methanol and the like are preferable.

  Moreover, as a preferable form of the copolymer used for a low refractive index layer, what is represented by the said General formula 1, ie, the thing of General formula 1 and General formula 2 of Unexamined-Japanese-Patent No. 2004-45462 is mentioned. Preferred specific examples are described in the publications [0043] to [0047], and synthesis methods are described in [0048] to [0053].

The inorganic particles that can be preferably used in the low refractive index layer in the antireflection film of the present invention will be described.
The coating amount of the inorganic fine particles is preferably ^{1mg / m 2 ~100mg / m 2} , more preferably ^{5mg / m 2 ~80mg / m 2} , more preferably from ^{10mg / m 2 ~60mg / m 2} . If the amount is too small, the effect of improving the scratch resistance is reduced. If the amount is too large, fine irregularities are formed on the surface of the low refractive index layer, and the appearance such as black tightening and the integrated reflectance are deteriorated.
Since the inorganic fine particles are contained in the low refractive index layer, it is desirable that the inorganic fine particles have a low refractive index. Examples thereof include fine particles of silica or hollow silica.

In the present invention, it is preferable to use hollow silica fine particles in order to reduce the refractive index of the low refractive index layer. The hollow silica fine particles preferably have a refractive index of 1.15 to 1.40, more preferably 1.17 to 1.40, still more preferably 1.17 to 1.35, and most preferably 1.17 to 1. 30. The refractive index here represents the refractive index of the entire particle, and does not represent the refractive index of only the outer shell silica forming the hollow silica fine particles. At this time, if the radius of the cavity in the particle is a and the radius of the particle outer shell is b, the porosity x expressed by the following formula (VIII) is (Formula VIII)
^{x = (4πa 3/3)} / (4πb 3/3) × 100
The porosity x is preferably 10 to 60%, more preferably 20 to 60%, and most preferably 30 to 60%. If hollow silica fine particles are made to have a lower refractive index and a higher porosity, the thickness of the outer shell becomes thinner and the strength of the particles becomes weaker. Rate particles are not preferred.
The method for producing hollow silica is described in, for example, Japanese Patent Application Laid-Open Nos. 2001-233611 and 2002-79616. In particular, particles having cavities inside the shell and having fine pores in the shell are particularly preferred. The refractive index of these hollow silica fine particles can be calculated by the method described in JP-A-2002-79616. The refractive index of these hollow silica particles was measured with an Abbe refractometer (manufactured by Atago Co., Ltd.).

The coating amount of the hollow silica fine particles is preferably ^{1mg / m 2 ~100mg / m 2} , more preferably ^{5mg / m 2 ~80mg / m 2} , more preferably from ^{10mg / m 2 ~60mg / m 2} . If the amount is too small, the effect of lowering the refractive index and the effect of improving the scratch resistance is reduced. If the amount is too large, fine irregularities are formed on the surface of the low refractive index layer, and the appearance such as black tightening and the integrated reflectance are deteriorated.
The average particle diameter of the hollow silica fine particles is preferably 30% or more and 150% or less of the thickness of the low refractive index layer, more preferably 35% or more and 80% or less, and further preferably 40% or more and 60% or less. That is, if the thickness of the low refractive index layer is 100 nm, the particle size of the hollow silica is preferably 30 nm to 150 nm, more preferably 35 nm to 80 nm, and still more preferably 40 nm to 60 nm.
If the particle size of the hollow silica fine particles is too small, the ratio of cavities will decrease and the refractive index will not decrease.If it is too large, fine irregularities will be formed on the surface of the low refractive index layer, the appearance of black tightening, integrated reflectance, etc. Gets worse. The hollow silica fine particles may be either crystalline or amorphous, and are preferably monodisperse particles. The shape is most preferably a spherical diameter, but there is no problem even if the shape is indefinite.
Moreover, two or more types of hollow silica having different particle average particle sizes can be used in combination. Here, the average particle diameter of the hollow silica can be determined from an electron micrograph.
Surface area of the hollow silica fine particles in the present invention is preferably from 20 to 300 m ² / g, more preferably 30~120m ² / g, most preferably 40~90m ² / g. The surface area can be determined by the BET method using nitrogen.

  Moreover, the refractive index of this layer can be reduced by containing hollow particles in the low refractive index layer. When the hollow particles are used, the refractive index of the layer is preferably 1.20 or more and 1.46 or less, more preferably 1.25 or more and 1.41 or less, and most preferably 1.30 or more and 1.39 or less. It is.

In the present invention, silica fine particles having no voids can be used in combination with hollow silica fine particles. The average particle diameter of the silica fine particles without voids is preferably 30% or more and 150% or less, more preferably 35% or more and 80% or less, and further preferably 40% or more and 60% or less of the thickness of the low refractive index layer. That is, when the thickness of the low refractive index layer is 100 nm, the particle diameter of the silica fine particles is preferably 30 nm to 150 nm, more preferably 35 nm to 80 nm, and still more preferably 40 nm to 60 nm.
If the particle size of the silica fine particles is too small, the effect of improving the scratch resistance is reduced. If it is too large, fine irregularities are formed on the surface of the low refractive index layer, and the appearance such as black tightening and the integrated reflectance are deteriorated.
The silica fine particles may be either crystalline or amorphous, and may be monodispersed particles or aggregated particles as long as a predetermined particle size is satisfied. The shape is most preferably a spherical diameter, but there is no problem even if the shape is indefinite.
Here, the average particle diameter of the inorganic fine particles is measured by a Coulter counter.
Further, at least one kind of silica fine particles having an average particle size of less than 25% of the thickness of the low refractive index layer (referred to as “small size particle size silica particles”) is used as silica fine particles having the above particle size (“large size particles”). It can also be used in combination with “diameter silica particles”.
Since the fine silica particles having a small particle size can exist in the gaps between the fine silica particles having a large particle size, they can contribute as a retaining agent for the fine silica particles having a large particle size.
When the low refractive index layer is 100 nm, the average particle size of the silica fine particles having a small size is preferably from 1 nm to 20 nm, more preferably from 5 nm to 15 nm, and particularly preferably from 10 nm to 15 nm. Use of such silica fine particles is preferable in terms of raw material costs and a retaining agent effect.

Hollow silica fine particles and silica fine particles are used in plasma dispersion treatment or corona discharge treatment in order to stabilize dispersion in the dispersion or coating solution, or to increase the affinity and binding properties with the binder component. A physical surface treatment or a chemical surface treatment with a surfactant or a coupling agent may be performed. The use of a coupling agent is particularly preferred. As the coupling agent, an alkoxy metal compound (eg, titanium coupling agent, silane coupling agent) is preferably used. Among these, treatment with a silane coupling agent having an acryloyl group or a methacryloyl group is particularly effective.
The above-mentioned coupling agent is used as a surface treatment agent for the inorganic fine particles of the low refractive index layer in advance for surface treatment prior to the preparation of the layer coating solution, and is further added as an additive during the preparation of the layer coating solution. It is preferable to make it contain in a layer.
The hollow silica fine particles and the silica fine particles are preferably dispersed in the medium in advance before the surface treatment in order to reduce the load of the surface treatment. Specific examples of the surface treatment agent and the catalyst that can be preferably used in the semi-invention include organosilane compounds and catalysts described in WO 2004/017105.

  In the present invention, it is preferable to add a hydrolyzate of organosilane and / or a partial condensate (sol) thereof from the viewpoint of improving the film strength. The preferable addition amount of sol is preferably 2 to 200% by mass of the inorganic oxide particles, more preferably 5 to 100% by mass, and most preferably 10 to 50% by mass. Preferable organosilanes include those described in paragraph numbers [0028] to [0045] of JP-A No. 2004-170901.

In the present invention, it is preferable to reduce the surface free energy on the surface of the antireflection film from the viewpoint of improving the antifouling property. Specifically, it is preferable to use a fluorine-containing compound or a compound having a polysiloxane structure (silicone compound) for the low refractive index layer.
Examples of the additive having a polysiloxane structure include reactive group-containing polysiloxanes (for example, KF-100T, X-22-169AS, KF-102, X-22-3701IE, X-22-164B, X-22-5002, X-22-173B, X-22-174D, X-22-167B, X-22-161AS (above trade name, manufactured by Shin-Etsu Chemical Co., Ltd.), AK-5, AK-30, AK-32 (above (Trade name, manufactured by Toa Gosei Co., Ltd.), Silaplane FM0725, Silaplane FM0721 (above trade name, manufactured by Chisso Corporation), DMS-U22, RMS-033, RMS-083, UMS-182, DMS-H21, DMS-H31, HMS-301, FMS121, FMS123, FMS131, FMS141, FMS221 (above trade names, Gelest It is also preferable to add the above).
In addition, X-22-174DX, X-22-2426, X-22-164B, X22-164C, X-22-170DX, X-22-176D, X-22-1821 (above) manufactured by Shin-Etsu Chemical Co., Ltd. (Trade name), manufactured by Chisso Corporation, FM-0725, FM-7725, FM-4421, FM-5521, FM6621, FM-1121, Gelest DMS-U22, RMS-033, RMS-083, UMS-182, Examples thereof include, but are not limited to, DMS-H21, DMS-H31, HMS-301, FMS121, FMS123, FMS131, FMS141, and FMS221 (and above are trade names).
In addition, silicone compounds described in [Table 2] and [Table 3] of JP-A No. 2003-112383 can also be preferably used. Furthermore, the compounds described in paragraph numbers [0031] to [0044] of JP-A No. 2003-329804 can also be preferably used. These polysiloxanes are preferably added in the range of 0.1 to 10% by mass of the total solid content of the low refractive index layer, particularly preferably 1 to 5% by mass.

The fluoropolymer can be polymerized by irradiation with ionizing radiation or heating in the presence of the above-mentioned photo radical initiator or thermal radical initiator.
Therefore, a coating solution containing the above-mentioned fluoropolymer, photoradical initiator or thermal radical initiator, and inorganic fine particles is prepared, and after coating the coating solution on a transparent substrate, it is cured by ionizing radiation or heat polymerization reaction. Thus, a low refractive index layer can be formed.

[Hard coat layer]
The hard coat layer has a hard coat property for improving the scratch resistance of the film. Moreover, it is preferably used also for the purpose of contributing to the film the light diffusibility due to scattering of at least one of surface scattering and internal scattering. Accordingly, the curable composition for forming the hard coat layer preferably contains a translucent resin for imparting hard coat properties and translucent particles for imparting light diffusibility, and further required. Accordingly, it is preferable to contain an inorganic filler for increasing the refractive index, preventing crosslinking shrinkage, and increasing the strength.

  The thickness of the hard coat layer is preferably 1 to 10 μm and more preferably 1.2 to 6 μm for the purpose of imparting hard coat properties. When the film thickness is in the above range, the hard coat property is sufficiently imparted, and further, the curability and brittleness are not deteriorated and the workability is not lowered.

The translucent resin is preferably a binder polymer having a saturated hydrocarbon chain or a polyether chain as a main chain, and more preferably a binder polymer having a saturated hydrocarbon chain as a main chain. The binder polymer preferably has a crosslinked structure.
As the binder polymer having a saturated hydrocarbon chain as a main chain, a polymer of an ethylenically unsaturated monomer is preferable. As the binder polymer having a saturated hydrocarbon chain as the main chain and having a crosslinked structure, a (co) polymer of monomers having two or more ethylenically unsaturated groups is preferable.
In order to make the binder polymer have a higher refractive index, the monomer structure contains an aromatic ring and at least one atom selected from halogen atoms other than fluorine, sulfur atoms, phosphorus atoms, and nitrogen atoms. A refractive index monomer can also be selected.

  Examples of the monomer having two or more ethylenically unsaturated groups include esters of polyhydric alcohol and (meth) acrylic acid [for example, ethylene glycol di (meth) acrylate, butanediol di (meth) acrylate, hexanediol di ( (Meth) acrylate, 1,4-cyclohexanediacrylate, pentaerythritol tetra (meth) acrylate, pentaerythritol tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolethane tri (meth) acrylate, dipentaerythritol tetra (Meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, pentaerythritol hexa (meth) acrylate, 1,2,3-si Rhohexanetetramethacrylate, polyurethane polyacrylate, polyester polyacrylate], ethylene oxide-modified products of the above esters, vinylbenzene and derivatives thereof (eg, 1,4-divinylbenzene, 4-vinylbenzoic acid-2-acryloylethyl ester, 1,4-divinylcyclohexanone], vinyl sulfone (eg, divinyl sulfone), acrylamide (eg, methylene bisacrylamide) and methacrylamide. Two or more of these monomers may be used in combination.

  Specific examples of the high refractive index monomer include bis (4-methacryloylthiophenyl) sulfide, vinyl naphthalene, vinyl phenyl sulfide, 4-methacryloxyphenyl-4′-methoxyphenyl thioether, and the like. Two or more of these monomers may be used in combination.

Polymerization of these monomers having an ethylenically unsaturated group can be performed by irradiation with ionizing radiation or heating in the presence of the polymerization initiator contained in the low refractive index layer.
Accordingly, the hard coat layer comprises a monomer for forming a light-transmitting resin such as the above-mentioned ethylenically unsaturated monomer, an initiator that generates radicals by ionizing radiation or heat, light-transmitting particles, and if necessary inorganic fine particles. It can be formed by preparing a coating solution to be contained and curing the coating solution on a transparent substrate by ionizing radiation or a polymerization reaction with heat.

  In addition to the polymerization initiator that generates radicals by ionizing radiation or heat, a photosensitizer that may be contained in the low refractive index layer may be used.

The polymer having a polyether as the main chain is preferably a ring-opening polymer of a polyfunctional epoxy compound. The ring-opening polymerization of the polyfunctional epoxy compound can be performed by irradiation with ionizing radiation or heating in the presence of a photoacid generator or a thermal acid generator.
Accordingly, a coating solution containing a polyfunctional epoxy compound, a photoacid generator or a thermal acid generator, translucent particles and inorganic fine particles is prepared, and the coating solution is applied onto a transparent substrate and then polymerized by ionizing radiation or heat. It can be cured by reaction to form a hard coat layer.

Instead of or in addition to a monomer having two or more ethylenically unsaturated groups, a monomer having a crosslinkable functional group is used to introduce a crosslinkable functional group into the polymer, and by reaction of this crosslinkable functional group, A crosslinked structure may be introduced into the binder polymer.
Examples of the crosslinkable functional group include isocyanate group, epoxy group, aziridine group, oxazoline group, aldehyde group, carbonyl group, hydrazine group, carboxyl group, methylol group and active methylene group. Vinylsulfonic acid, acid anhydride, cyanoacrylate derivative, melamine, etherified methylol, ester and urethane, and metal alkoxide such as tetramethoxysilane can also be used as a monomer for introducing a crosslinked structure. A functional group that exhibits crosslinkability as a result of the decomposition reaction, such as a block isocyanate group, may be used. That is, in the present invention, the crosslinkable functional group may not react immediately but may exhibit reactivity as a result of decomposition.
These binder polymers having a crosslinkable functional group can form a crosslinked structure by heating after coating.
The haze of the hard coat layer varies depending on the function imparted to the antireflection film.
When maintaining the sharpness of the image, suppressing the reflectance of the surface, and having no light scattering function, the haze value is preferably as low as possible, specifically 10% or less, more preferably 5% or less. Yes, most preferably 2% or less.
On the other hand, in addition to the function of suppressing the reflectance of the surface, when it becomes difficult to see the pattern, color unevenness, brightness unevenness, etc. of the liquid crystal panel due to scattering, or the function of expanding the viewing angle due to scattering is given, the haze value is 10 % To 90%, more preferably 15% to 80%, and most preferably 20% to 70%.

The translucent particles used in the hard coat layer are used for the purpose of imparting antiglare property or light diffusibility, and have an average particle size of 0.5 to 5 μm, preferably 1.0 to 4.0 μm. is there.
If the average particle size is less than 0.5 μm, the light scattering angle distribution spreads to a wide angle, resulting in a decrease in the character resolution of the display, and it becomes difficult to form surface irregularities, resulting in insufficient antiglare properties. Therefore, it is not preferable. On the other hand, when the thickness exceeds 5 μm, it is necessary to increase the thickness of the hard coat layer, which causes problems such as an increase in curling and an increase in material cost.
Specific examples of the translucent particles include particles of inorganic compounds such as silica particles and TiO ₂ particles; acrylic particles, crosslinked acrylic particles, methacrylic particles, crosslinked methacrylic particles, polystyrene particles, crosslinked styrene particles, melamine resin particles, Preferred examples include resin particles such as benzoguanamine resin particles. Of these, crosslinked styrene particles, crosslinked acrylic particles, crosslinked acrylic styrene particles, and silica particles are preferable.
The translucent particles can be either spherical or indefinite.

  Moreover, you may use together and use 2 or more types of translucent particle | grains from which a particle diameter differs. It is possible to impart an antiglare property with a light-transmitting particle having a larger particle size and to impart another optical characteristic with a light-transmitting particle having a smaller particle size. For example, when an antireflection film is attached to a high-definition display of 133 ppi or higher, it is required that there is no problem in optical performance called glare. Glare is derived from the fact that the unevenness of the film surface (which contributes to antiglare properties) causes the pixels to be enlarged or reduced and loses brightness uniformity, but is smaller than the light-transmitting particles that impart antiglare properties. The diameter can be greatly improved by using translucent particles different from the refractive index of the binder.

  Further, the particle size distribution of the translucent particles is most preferably monodispersed, and the particle size of each particle is preferably as close as possible. For example, when a particle having a particle size of 20% or more than the average particle size is defined as a coarse particle, the proportion of the coarse particle is preferably 1% or less, more preferably 0.1% of the total number of particles. Or less, more preferably 0.01% or less. The translucent particles having such a particle size distribution are obtained by classification after a normal synthesis reaction, and a more preferable distribution can be obtained by increasing the number of classifications or increasing the degree thereof.

The light-transmitting particles are preferably 3 to 30% by mass in the total solid content of the hard coat layer in consideration of light scattering effect, image resolution, surface turbidity, glare and the like in the formed hard coat layer. Formulated to contain. More preferably, it is 5-20 mass%.
Moreover, the density of the translucent particles is preferably 10 to 1000 mg / m ² , more preferably 100 to 700 mg / m ² .
The particle size distribution of the translucent particles is measured by a Coulter counter method, and the measured distribution is converted into a particle number distribution.

In order to increase the refractive index of the hard coat layer, in addition to the above light-transmitting particles, at least one metal selected from titanium, zirconium, aluminum, indium, zinc, tin, and antimony is used. It is preferable to contain inorganic fine particles made of an oxide and having an average particle size of 0.2 μm or less, preferably 0.1 μm or less, more preferably 0.06 μm or less.
Conversely, in order to increase the difference in refractive index from the light-transmitting particles, the hard coat layer using the high-refractive index light-transmitting particles uses silicon oxide to keep the refractive index of the layer low. It is also preferable. The preferred particle size is the same as that of the inorganic fine particles.
Specific examples of the inorganic fine particles used for the hard coat layer include TiO ₂ , ZrO ₂ , Al ₂ O ₃ , In ₂ O ₃ , ZnO, SnO ₂ , Sb ₂ O ₃ , ITO and SiO ₂ . TiO ₂ and ZrO ₂ are particularly preferable from the viewpoint of increasing the refractive index. The inorganic fine particles are also preferably subjected to a silane coupling treatment or a titanium coupling treatment on the surface, and a surface treatment agent having a functional group capable of reacting with a binder species on the fine particle surface is preferably used.
When using these inorganic fine particles, the addition amount is preferably 10 to 90% by mass, more preferably 20 to 80% by mass, and particularly preferably 30 to 75% by mass with respect to the total mass of the hard coat layer. It is.
Such inorganic fine particles have a particle size sufficiently smaller than the wavelength of light and therefore do not scatter, and a dispersion in which the fine particles are dispersed in a binder polymer behaves as an optically uniform substance.
Also, at least one of an organosilane compound, a hydrolyzate of organosilane and / or a partial condensate (sol) thereof can be used for the hard coat layer.
The amount of the sol component added to the layers other than the low refractive index layer is preferably 0.001 to 50% by mass, more preferably 0.01 to 20% by mass, based on the total solid content of the containing layer (added layer). 05-10 mass% is still more preferable, and 0.1-5 mass% is especially preferable. In the case of the hard coat layer, the organosilane compound is preferably used because the restriction on the amount of the organosilane compound or its sol component added is not as strict as the low refractive index layer.

The bulk refractive index of the mixture of translucent resin and translucent particles is preferably 1.48 to 2.00, more preferably 1.50 to 1.80. In order to set the refractive index within the above range, the kind and amount ratio of the light-transmitting resin and the light-transmitting particles may be appropriately selected. How to select can be easily known experimentally in advance.
The difference in refractive index between the translucent resin and the translucent particles (the refractive index of the translucent particles−the refractive index of the translucent resin) is preferably 0.02 to 0.2, and more preferably 0.05. ~ 0.15. When this difference is within the above range, the effect of internal scattering is sufficient, no glare occurs, and the film surface does not become cloudy.
The refractive index of the translucent resin is preferably 1.45 to 2.00, more preferably 1.48 to 1.70.
Here, the refractive index of the translucent resin can be quantitatively evaluated by directly measuring it with an Abbe refractometer or by measuring a spectral reflection spectrum or a spectral ellipsometry.

In order to ensure surface uniformity such as uneven coating, uneven drying, point defects, etc., the hard coat layer should be coated with either a fluorine-based or silicone-based surfactant, or both for forming a hard coat layer. Contained in the liquid. In particular, a fluorine-based surfactant is preferably used because an effect of improving surface defects such as coating unevenness, drying unevenness, and point defects of the antireflection film of the present invention appears in a smaller addition amount.
The purpose is to increase productivity by giving high-speed coating suitability while improving surface uniformity.

[Anti-glare layer]
Next, the antiglare layer will be described below.
The antiglare layer is formed for the purpose of contributing to the film antiglare properties due to surface scattering and preferably hard coat properties for improving the scratch resistance of the film. Therefore, it preferably contains a translucent resin capable of imparting hard coat properties, translucent fine particles for imparting antiglare properties, and a solvent as essential components. As the light-transmitting resin and the light-transmitting fine particles, the same hard coat as that described above can be used.
Below, the suitable structural example of the antireflection film of this invention is demonstrated, referring drawings. Here, FIG. 5 is a cross-sectional view schematically showing an example of an antireflection film having antiglare properties.

An antiglare antireflection film 1 shown in FIG. 5 includes a transparent base material 2, an antiglare layer 3 formed on the transparent base material 2, and a low refractive index layer 4 formed on the antiglare layer 3. Consists of. By forming the low refractive index layer on the antiglare layer with a film thickness of about ¼ of the wavelength of light, surface reflection can be reduced by the principle of thin film interference.
The antiglare layer 3 includes a translucent resin and translucent fine particles 5 dispersed in the translucent resin.
In the antireflection film having the above configuration, the refractive index of each layer preferably satisfies the following relationship.
The refractive index of the antiglare layer> the refractive index of the transparent substrate> the refractive index of the low refractive index layer In the present invention, the antiglare layer having antiglare properties preferably has both antiglare properties and hard coat properties, In this embodiment, although what was formed by 1 layer is illustrated, you may be comprised by multiple layers, for example, 2 layers-4 layers. Moreover, although you may provide directly on a transparent base material like this embodiment, you may provide via other layers, such as an antistatic layer and a moisture-proof layer.

When an antiglare layer is provided on the antireflection film of the present invention, the center line average roughness Ra is 0.08 to 0.30 μm, and the 10-point average roughness Rz is 10 times or less of Ra, the average as the surface uneven shape of the film. The mountain valley distance Sm is 1 to 100 μm, the standard deviation of the height of the convex part from the deepest part of the unevenness is 0.5 μm or less, the standard deviation of the average mountain valley distance Sm based on the center line is 20 μm or less, It is preferable to design the surface to be 10% or more because sufficient anti-glare properties and a visually uniform mat feeling can be achieved. If Ra is less than 0.08, sufficient antiglare property cannot be obtained, and if it exceeds 0.30, problems such as glare and surface whitening when external light is reflected occur.
Further, the minimum reflectance of the reflected light in the CIE 1976 L ^* a ^* b ^* color space under the C light source is in the range of a ^* value −2 to 2, b ^* value −3 to 3, 380 nm to 780 nm. A ratio between the value and the maximum value of 0.5 to 0.99 is preferable because the color of the reflected light becomes neutral. Moreover, when the b ^* value of the transmitted light under the C light source is set to 0 to 3, the yellow color of white display when applied to a display device is reduced, which is preferable.

  In addition, in the case of imparting antiglare properties to the antireflection film of the present invention, the haze resulting from internal scattering of the optical properties (hereinafter referred to as internal haze) is preferably 5% to 20%, More preferably, it is 5% to 15%. If the internal haze is less than 5%, combinations of materials that can be used are limited, and it is difficult to match antiglare and other characteristic values, and the cost is high. When the internal scattering exceeds 20%, the dark room contrast is greatly deteriorated. Further, haze caused by surface scattering (hereinafter referred to as surface haze) is preferably 1% to 10%, more preferably 2% to 7%, and a transmission image at a comb width of 0.5 mm. A sharpness of 5% to 30% is preferable because sufficient antiglare properties and improvement in image blur and dark room contrast reduction are compatible. If the surface haze is less than 1%, the antiglare property is insufficient, and if it exceeds 10%, problems such as whitening of the surface when external light is reflected occur. Moreover, it is preferable that the specular reflectance is 2.5% or less and the transmittance is 90% or more because reflection of external light can be suppressed and visibility is improved.

[High (medium) refractive index layer]
In order to impart better antireflection performance to the antireflection film of the present invention, it is preferable to provide a high refractive index layer and / or a medium refractive index layer. The refractive index of the high refractive index layer in the antireflection film of the present invention is preferably 1.60 to 2.40, and more preferably 1.70 to 2.20. The refractive index of the middle refractive index layer is adjusted to be a value between the refractive index of the low refractive index layer and the refractive index of the high refractive index layer. The refractive index of the middle refractive index layer is preferably 1.55 to 1.80. The haze of the high refractive index layer and the medium refractive index layer is preferably 3% or less. The refractive index can be adjusted as appropriate by adjusting the amount of inorganic filler or binder used.

The high (medium) refractive index layer is made of an oxide of at least one metal selected from titanium, zirconium, aluminum, indium, zinc, tin, and antimony in order to increase the refractive index of the layer. Is preferably 0.2 μm or less, preferably 0.1 μm or less, more preferably 0.06 μm or less.
Further, in order to increase the difference in refractive index from the mat particles contained in the high (medium) refractive index layer, the high (medium) refractive index layer using the high refractive index mat particles has a low refractive index. It is also preferred to use silicon oxide to maintain. The preferred particle size is the same as that of the inorganic filler in the hard coat layer described above.
Specific examples of the inorganic filler used in the high (medium) refractive index layer include TiO ₂ , ZrO ₂ , Al ₂ O ₃ , In ₂ O ₃ , ZnO, SnO ₂ , Sb ₂ O ₃ , ITO and SiO _2. Can be mentioned. TiO ₂ and ZrO ₂ are particularly preferable from the viewpoint of increasing the refractive index. The surface of the inorganic filler is preferably subjected to a silane coupling treatment or a titanium coupling treatment, and a surface treatment agent having a functional group capable of reacting with a binder species on the filler surface is preferably used.
The addition amount of these inorganic fillers is adjusted according to the required refractive index, but in the case of a high refractive index layer, it is preferably 10 to 90% of the total mass, more preferably 20 to 80%, Especially preferably, it is 30 to 70%.
In addition, since such a filler has a particle size sufficiently smaller than the wavelength of light, scattering does not occur, and a dispersion in which the filler is dispersed in a binder polymer behaves as an optically uniform substance.

  The high (medium) refractive index layer used in the present invention is preferably a film-forming binder component necessary for matrix formation (the aforementioned hard coat layer) in the dispersion liquid in which the inorganic fine particles are dispersed in the dispersion medium as described above. A monomer having two or more ethylenically unsaturated groups as described in 1), a photopolymerization initiator and the like to form a coating composition for forming a high refractive index layer, and for forming a high refractive index layer on a transparent substrate. The coating composition is preferably applied and cured by a crosslinking reaction or a polymerization reaction of an ionizing radiation curable compound (for example, a polyfunctional monomer or a polyfunctional oligomer).

  It is preferable to use a photopolymerization initiator for the polymerization reaction of the photopolymerizable polyfunctional monomer. As the photopolymerization initiator, a photoradical polymerization initiator and a photocationic polymerization initiator are preferable, and a photoradical polymerization initiator is particularly preferable. As the radical photopolymerization initiator, the same one as the above-mentioned low refractive index layer is used.

In addition to the above-mentioned components (inorganic fine particles, polymerization initiators, photosensitizers, etc.), the high (medium) refractive index layer contains resins, surfactants, antistatic agents, coupling agents, thickeners, and coloring prevention. Agent, coloring agent (pigment, dye), anti-glare imparting particles, antifoaming agent, leveling agent, flame retardant, ultraviolet absorber, infrared absorber, adhesion promoter, polymerization inhibitor, antioxidant, surface modifier In addition, conductive metal fine particles can be added.
The film thickness of the high (medium) refractive index layer can be appropriately designed depending on the application. When a high (medium) refractive index layer is used as the optical interference layer, the thickness is preferably 30 to 200 nm, more preferably 50 to 170 nm, and particularly preferably 60 to 150 nm.

[Transparent substrate]
As the transparent substrate of the antireflection film of the present invention, it is preferable to use a plastic film. As the polymer forming the plastic film, cellulose acylate (eg, cellulose triacetate, cellulose diacetate, cellulose acetate propionate, cellulose acetate butyrate, typically TAC-TD80U, TD80UF, etc. manufactured by Fuji Photo Film), Polyamide, polycarbonate, polyester (eg, polyethylene terephthalate, polyethylene naphthalate), polystyrene, polyolefin, norbornene resin (Arton: trade name, manufactured by JSR), amorphous polyolefin (ZEONEX: trade name, manufactured by ZEON Corporation), Etc. Of these, triacetyl cellulose, polyethylene terephthalate, and polyethylene naphthalate are preferable, and triacetyl cellulose is particularly preferable. Also, the cellulose acylate film substantially free of halogenated hydrocarbons such as dichloromethane and the production method thereof are disclosed in JIII Journal of Technical Disclosure (Publication No. 2001-1745, published on March 15, 2001; The cellulose acylate described here can also be preferably used in the present invention.

[Coating method]
The optical film of the present invention, particularly the antireflection film, can be formed by the following method, but is not limited to this method. Hereinafter, the method for forming a coating film of the optical film of the present invention will be described taking an antireflection film as an example.
[Method for producing antireflection film]
<Formation by application of antireflection film>
When the antireflection film has a multi-layer configuration, each layer laminated on the transparent substrate includes a dip coating method, an air knife coating method, a curtain coating method, a roller coating method, a die coating method, a wire bar coating method, a gravure coating method, It can be formed by coating by an extrusion coating method (described in US Pat. No. 2,681,294). Two or more layers may be applied simultaneously. The method of simultaneous application is described in US Pat. Nos. 2,761,791, 2,941,898, 3,508,947, and 3,526,528 and Yuji Harasaki, Coating Engineering, page 253, Asakura Shoten (1973).

In order to continuously produce the antireflection film of the present invention, a step of continuously feeding a roll-shaped base film, a step of applying and drying a coating liquid (that is, a step of forming a coating layer), a coating film The process of hardening (coating layer) and the process of winding up the base film which has the hardened layer are performed.
The base film is continuously fed from the roll-shaped base film to the clean room. In the clean room, the static electricity charged in the base film is removed by the electrostatic static neutralizer, and then it adheres to the base film. Remove the foreign material that has been removed with a dust remover. Subsequently, the coating solution is applied onto the base film in the coating unit installed in the clean room, and the coated base film is sent to the drying room and dried.
The base film having the dried coating layer is fed from the drying chamber to the radiation curing chamber, irradiated with radiation, and the monomer contained in the coating layer is polymerized and cured. Furthermore, if necessary, the base film having a layer cured by radiation is sent to the thermosetting section and heated to complete the curing, and the base film having the cured layer is wound up and rolled. It becomes.

The above process may be performed every time each layer is formed, or a plurality of coating units-drying chambers-radiation curing units-thermosetting chambers may be provided to form each layer continuously. In view of the above, it is preferable to continuously form each layer. An example of the configuration of an apparatus for continuously applying each layer is shown in FIG. The apparatus has a necessary number of film forming units 100, 200, 300, and 400 appropriately installed between the step 6 for continuously feeding a roll-shaped base film and the step 7 for winding the roll-shaped base film. Is. The apparatus shown in FIG. 6 is an example of a configuration when four layers are continuously applied without winding up, but it is of course possible to change the number of film forming units according to the layer configuration. The film forming unit 100 includes a process 101 for applying a coating liquid, a process 102 for drying a coating film, and a process 103 for curing the coating film. For example, in the case of producing an antireflection film having a hard coat layer, a medium refractive index layer, a high refractive index layer and a low refractive index layer, the hard coat layer is prepared using an apparatus in which three film forming units are installed. It is more preferable to continuously feed out a roll-shaped substrate film coated with a medium refractive index layer, a high refractive index layer, and a low refractive index layer in order in each film forming unit, and to wind the film. Using the apparatus shown in FIG. 6 in which four units are installed, a roll-shaped base film is continuously fed, and a hard coat layer, a medium refractive index layer, a high refractive index layer, and a low refractive index layer are manufactured. More preferably, the film unit is sequentially coated and then wound.
Hereinafter, each of the coating process and the conveyance / curing process will be described.

In the present invention, a die coating method is preferably used as a coating method from the viewpoint of a higher production rate. The die coating method is preferably used because it can achieve a high level of productivity and a surface shape without coating unevenness.
As a manufacturing method of the antireflection film of the present invention, the following coating method using such a die coating method is preferable.
That is, the manufacturing method includes a coating step of applying a coating liquid from the slot of the tip lip by bringing the land of the tip lip of the slot die close to the surface of the web supported continuously by the backup roll. The slot die has a slot die whose land length in the web traveling direction of the tip lip on the web traveling direction side of the slot die is 30 μm or more and 100 μm or less, and is opposite to the web traveling direction when the slot die is set at the coating position. The gap between the tip lip and the web on the side is larger by 30 μm or more and 120 μm or less than the gap between the tip lip on the web traveling direction side and the web (hereinafter, this numerical limitation is referred to as “over bit length”). Apply each layer on the transparent base material of the antireflection film using a coating device installed Preferred.
In particular, a die coater that can be preferably used in the production method of the present invention will be described below with reference to the drawings. The die coater can be used when the wet coating amount is small (20 ml / m ² or less), and is preferable.

<Die coater configuration>
FIG. 7 is a cross-sectional view of a coater (coating device) using a slot die that can suitably implement the present invention.
The coater 10 includes a backup roll 11 and a slot die 13, and the coating liquid 14 is discharged from the slot die 13 in a bead shape 14 a and applied to the web W that is continuously supported by the backup roll 11. Thus, the coating film 14b is formed on the web W.

  Inside the slot die 13, a pocket 15 and a slot 16 are formed. The pocket 15 has a curved section and a straight section, and may be substantially circular or semicircular. The pocket 15 extends with its cross-sectional shape in the width direction of the slot die 13 (here, the width direction of the slot die 13 refers to the front side or the back side toward the drawing shown in FIG. 7). In the liquid storage space for the applied coating solution, the effective extension length is generally equal to or slightly longer than the coating width. The supply of the coating liquid 14 to the pocket 15 is performed from the side surface of the slot die 13 or from the center of the surface opposite to the slot opening 16a. The pocket 15 is provided with a stopper (not shown) that prevents the coating liquid 14 from leaking out.

  The slot 16 is a flow path of the coating liquid 14 from the pocket 15 to the web W, and has a cross-sectional shape in the width direction of the slot die 13 similarly to the pocket 15, and the opening 16a located on the web side is generally Using a thing such as a width regulating plate (not shown), the length is adjusted to be approximately the same as the coating width. The angle between the slot tip of the slot 16 and the tangent in the running direction of the web W of the backup roll 11 is preferably 30 ° or more and 90 ° or less.

The tip lip 17 of the slot die 13 where the opening 16a of the slot 16 is located is tapered, and the tip is a flat portion 18 called a land. The upstream side of the land 18 with respect to the slot 16 in the moving direction of the web W (the moving direction, that is, the direction opposite to the arrow direction in the figure) is the upstream lip land 18a, and the downstream side (the moving direction side) is downstream. This is called side lip land 18b.
The gap between the upstream lip land 18a and the web W is larger in the above-mentioned range than the gap between the downstream lip land 18b and the web W. The length of the downstream lip land land 18b is in the above-described range.
Referring to FIG. 8A, the part relating to the numerical limitation described above will be described. The land length on the web traveling direction side is a portion indicated by _ILO in FIG. Is a portion indicated by LO in FIG.

Next, with reference to FIG. 8, the coating apparatus preferably used for the implementation of the method for producing an antireflection film of the present invention will be described in comparison with a conventional coating apparatus. Here, FIG. 8 shows the sectional shape of the slot die 13 in comparison with the conventional one, (A) shows the slot die 13 of the present invention, and (B) shows the conventional slot die 30. Yes.
In the conventional slot die 30, the distance between the upstream lip land 31a and the web of the downstream lip land 31b is equal. Reference numeral 32 denotes a pocket, and 33 denotes a slot.
On the other hand, in the slot die 13 of the present invention, the downstream side lip land length I _LO is shortened, whereby the wet film thickness of 20 μm or less can be applied with high accuracy.

The land length I _UP of the upstream lip land 18a is not particularly limited, but is preferably used in the range of 500 μm to 1 mm. As described above, the land length I _LO of the downstream lip land 18b is preferably 30 μm or more and 100 μm or less, more preferably 30 μm or more and 80 μm or less, and most preferably 30 μm or more and 60 μm or less. If the land length I _LO of the downstream lip is 30 μm or more, it is preferable that the edge or land of the tip lip is difficult to be chipped, and the generation of streaks on the coating film can be suppressed. Easy to do.
Furthermore, the spread of the coating liquid on the downstream side can be suppressed, which is preferable. Spreading of the coating liquid on the downstream side due to wetting means non-uniformity of the wetting line and leads to a problem of causing a defective shape such as a streak on the coating surface. On the other hand, if the land length I _LO of the downstream lip is 100 μm or less, the bead 14a can be formed. When the coating solution forms the bead 14a, thin layer coating can be performed.

Further, the downstream lip land 18b has an overbite shape closer to the web W than the upstream lip land 18a. Therefore, the degree of decompression can be reduced, and a bead formation 14a suitable for thin film coating is possible. The difference in distance between the downstream side lip land 18b and the web W of the upstream side lip land 18a (hereinafter referred to as overbit length LO) is preferably 30 μm or more and 120 μm or less, more preferably 30 μm or more and 100 μm or less, and most preferably 30 μm. It is 80 μm or less. When the slot die 13 has an overbite shape, the gap _GL between the tip lip 17 and the web W indicates the gap between the downstream lip land 18b and the web W.

Next, with reference to FIG. 9, the entire coating process will be described.
FIG. 9 is a perspective view showing the slot die 13 and its periphery in the coating process performed in the production of the antireflection film of the present invention. A decompression chamber 40 is installed at a position where it does not come into contact with the slot die 13 on the side opposite to the traveling direction side of the web W (that is, on the upstream side of the bead 14a) so that sufficient decompression adjustment can be performed on the bead 14a. Vacuum chamber 40, the gap between its operating efficiency has a back plate 40a and side plates 40b for holding a gap between the back plate 40a and the web W G _B, the side plate 40b and the web W G _S exists.
The relationship between the decompression chamber 40 and the web W will be described with reference to FIGS. 10 and 11 are cross-sectional views showing the decompression chamber 40 and the web W that are close to each other.
Side plate 40b and the back plate 40a is may be of the chamber 40 body and integrally as shown in FIG. 10, for example, the back plate 40a to be appropriately changed gap G _B as shown in FIG. 11 to the chamber 40 A structure that is fastened with a screw 40c or the like may be used. In any structure, portions that are actually opened between the back plate 40a and the web W and between the side plate 40b and the web W are defined as gaps G _B and G _S , respectively. The gap G _B between the back plate 40a and the web W of the decompression chamber 40, when the vacuum chamber 40 is placed under the web W and the slot die 13 as shown in FIG. 9, the uppermost end of the back plate 40a to the web W Indicates the gap.

Is preferably installed to be larger than the gap G _L (see FIG. 8) between the end lip 17 and the web W of the back plate 40a and the clearance between the web W G _B the slot die 13, thereby the eccentricity of the backup roll 11 It is possible to suppress a change in the degree of decompression in the vicinity of the bead due to. For example, when the gap G _L between the end lip 17 and the web W of the slot die 13 is 30μm or more 100μm or less, the gap G _B between the back plate 40a and the web W is preferably 100μm or 500μm or less.

<Material and accuracy>
The length in the web running direction of the traveling direction side of the end lip of the web (the downstream lip land length shown in FIG. 8 (A) l _LO) is preferably in the range described above, also the l _LO It is preferable that the fluctuation width in the slot die width direction is within 20 μm. Within this range, it is preferable that the bead does not become unstable due to slight disturbance.
As for the material of the tip lip of the slot die, it is not preferable to use a material such as stainless steel because it will sag at the stage of die processing. In the case of stainless steel or the like, it is difficult to satisfy the accuracy of the tip lip even if the downstream lip land length l _LO is in the range of 30 to 100 μm. In order to maintain high processing accuracy, it is preferable to use a cemented carbide material as described in Japanese Patent No. 2817053. Specifically, at least the tip lip of the slot die is preferably made of a cemented carbide formed by bonding carbide crystals having an average particle size of 5 μm or less. Cemented carbides include carbide crystal particles such as tungsten carbide (hereinafter referred to as WC) bonded by a bonding metal such as cobalt, and other bonding metals include titanium, tantalum, niobium, and mixed metals thereof. Can also be used. The average particle size of the WC crystal is more preferably 3 μm or less.
The downstream lip land length l _LO is important for realizing high-precision coating, and it is desirable to control the fluctuation width of the gap _{GL in} the slot die width direction. It is desirable that the backup roll 11 and the tip lip 17 achieve straightness within a range in which the fluctuation range of the gap _{GL in} the slot die width direction can be controlled. Preferably, the straightness of the tip lip 17 and the backup roll 11 is set so that the fluctuation width of the gap _{GL in} the slot die width direction is 5 μm or less.

In the antireflection film of the present invention, it is preferable to laminate at least a high refractive index layer and a low refractive index layer. In the laminated structure, when a foreign matter such as dust or dust is present, bright spot defects are easily noticeable. The bright spot defect in the present invention is a defect that can be seen by reflection on the coating film as described above, and can be detected by an operation such as black coating on the back surface of the antireflection film after coating. The bright spot defects that can be visually observed are generally 50 μm or more. When there are many bright spot defects, the yield at the time of manufacture falls, and a large-area antireflection film cannot be manufactured.
In the antireflection film of the present invention, the number of bright spot defects is 20 or less per square meter, preferably 10 or less, more preferably 5 or less, and particularly preferably 1 or less.

In order to prepare an antireflection film with few bright spot defects, it is possible to precisely control the degree of dispersion of the high-refractive index ultrafine particles in the coating material for the high-refractive index layer, and to perform a fine filtration operation of the coating solution.
At the same time, each layer forming the antireflection layer is subjected to a dust process on the film before the coating process in the coating unit and the drying process performed in the drying chamber are performed in a high clean air atmosphere, and before the coating is performed. It is preferable that dust is sufficiently removed. The air cleanliness of the coating process and the drying process is preferably class 10 (353 particles / (cubic meter) or less of particles of 0.5 μm or more) based on the standard of air cleanliness in the US Federal Standard 209E, Preferably, it is preferably class 1 (particles of 0.5 μm or more are 35.5 particles / (cubic meter) or less) or more. Moreover, it is more preferable that the degree of air cleanliness is high also in the feeding and winding parts other than the coating-drying process.

As a dust removal method used in a dust removal step as a pre-process for coating, a method of pressing a nonwoven fabric, a blade or the like against the film surface described in JP-A-59-150571, described in JP-A-10-309553 Highly clean air is blown at a high speed to peel off the deposit from the film surface, and suction is performed at a suction port adjacent to the film. Ultrasonic-vibrated compressed air described in JP-A-7-333613 is sprayed onto the deposit. And a dry dust removal method such as a method of peeling and suctioning (manufactured by Shinkosha, New Ultra Cleaner, etc.).
In addition, a method of introducing a film into a cleaning tank and peeling off the adhered material by an ultrasonic vibrator, supplying a cleaning liquid to the film described in Japanese Patent Publication No. 49-13020, and then blowing and sucking high-speed air As described in JP-A-2001-38306, a wet dust removal method such as a method in which the web is continuously rubbed with a roll wetted with a liquid and then the liquid is sprayed onto the rubbed surface to be washed. Can do. Among such dust removal methods, a method using ultrasonic dust removal or a method using wet dust removal is particularly preferable from the viewpoint of dust removal effect.

  In addition, it is particularly preferable to remove static electricity on the base film before performing such a dust removal step in terms of increasing dust removal efficiency and suppressing dust adhesion. As such a static elimination method, a corona discharge ionizer, a light irradiation ionizer such as UV or soft X-ray, or the like can be used. The charged voltage of the base film before and after dust removal and application is desirably 1000 V or less, preferably 300 V or less, and particularly preferably 100 V or less.

(Dispersion medium for coating)
The dispersion medium for coating is not particularly limited. You may use individually or in mixture of 2 or more types. Preferred dispersion media include aromatic hydrocarbons such as toluene, xylene and styrene, chlorinated aromatic hydrocarbons such as chlorobenzene and orthodichlorobenzene, methane derivatives such as monochloromethane, ethane derivatives such as monochloroethane, and the like. Chlorinated aliphatic hydrocarbons, alcohols such as methanol, isopropyl alcohol and isobutyl alcohol, esters such as methyl acetate and ethyl acetate, ethers such as ethyl ether and 1,4-dioxane, acetone, methyl ethyl ketone, methyl isobutyl ketone, Examples include ketones such as cyclohexanone, glycol ethers such as ethylene glycol monomethyl ether, alicyclic hydrocarbons such as cyclohexane, aliphatic hydrocarbons such as normal hexane, and mixtures of aliphatic or aromatic hydrocarbons. Among these solvents, a dispersion medium for coating prepared by alone or a mixture of two or more ketones is particularly preferable.

[Coating liquid properties]
In the above-described coating method, the upper limit speed at which coating can be performed is greatly affected by the liquid physical properties, so it is necessary to control the liquid physical properties, particularly the viscosity and surface tension, at the moment of coating.
The viscosity is preferably 2.0 [mPa · sec] or less, more preferably 1.5 [mPa · sec] or less, and most preferably 1.0 [mPa · sec] or less. Since there are some coating solutions whose viscosity changes depending on the shear rate, the above value indicates the viscosity at the shear rate at the moment of coating. When a thixotropic agent is added to the coating solution, the viscosity is low at the time of coating with high shear, and when the coating solution is hardly sheared, if the viscosity is high, unevenness during drying is less likely to occur, which is preferable. The viscosity was measured using a vibration viscometer CJV-5000 (manufactured by A & D Co., Ltd.), the measurement range was 50 mV, and the measurement temperature was 25 ° C.
Moreover, although it is not a liquid physical property, the quantity of the coating liquid apply | coated to a web also affects the upper limit speed | rate which can be apply | coated. Preferably the amount of the coating solution to be applied on the web is 2.0~5.0 [ml / m ^2], and more preferably 3.0~5.0 [ml / m ^2]. Increasing the amount of coating liquid applied to the web increases the maximum speed at which coating is possible, but increasing the amount of coating liquid applied to the web increases the load on drying, so the liquid formulation / process It is preferable to determine the amount of coating solution to be applied to the optimal web depending on the conditions.
The surface tension of the coating solution is preferably in the range of 15 to 36 [mN / m].
It is preferable to reduce the surface tension by adding a leveling agent or the like because unevenness during drying is suppressed. On the other hand, if the surface tension is too low, the upper limit speed that can be applied is reduced, and therefore the range of 17 to 32 [mN / m] is more preferable, and the range of 19 to 26 [mN / m] is more preferable.
The speed | rate which apply | coats a coating liquid to a web surface becomes like this. Preferably it is 25 [m / min] or more, More preferably, it is 40-100 [m / min].
<Application speed>
By achieving the accuracy of the backup roller 11 and the tip lip 17 as described above, the coating method employed in the present invention has high film thickness stability during high-speed coating. Furthermore, since the coating method employed in the present invention is a pre-measuring method, it is easy to ensure a stable film thickness even during high-speed coating.

  The coating method employed in the present invention can be applied at high speed and with good film thickness stability to a coating solution having a low coating amount such as the antireflection film of the present invention. Although application is possible by other application methods, the dip coating method inevitably causes vibration of the application liquid in the liquid receiving tank, and stepped unevenness is likely to occur. In the reverse roll coating method and the micro gravure method, stepped unevenness is likely to occur due to roll eccentricity and deflection related to coating.

  Also, in the microgravure method, coating amount unevenness is likely to occur due to the manufacturing accuracy of the gravure roll and the change with time of the roll and blade due to the contact between the blade and the gravure roll. Moreover, since these application methods are post-measuring methods, it is difficult to ensure a stable film thickness. By using the production method of the present invention, it is preferable from the viewpoint of productivity to apply at a rate of 25 m / min or more.

(filtration)
The coating solution used for coating is preferably filtered before coating. As a filter for filtration, it is preferable to use a filter having a pore diameter as small as possible within a range in which components in the coating solution are not removed. For the filtration, a filter having an absolute filtration accuracy of 0.1 to 10 μm is used, and a filter having an absolute filtration accuracy of 0.1 to 5 μm is preferably used. The thickness of the filter is preferably 0.1 to 10 mm, and more preferably 0.2 to 2 mm. In that case, the filtration pressure is preferably 1.5 MPa or less, more preferably 1.0 MPa or less, and further preferably 0.2 MPa or less.
The filtration filter member is not particularly limited as long as it does not affect the coating solution. Specifically, the same thing as the filtration member of the wet dispersion of an inorganic compound mentioned above is mentioned.
It is also preferable to ultrasonically disperse the filtered coating solution immediately before coating to assist defoaming and dispersion holding of the dispersion.

[Polarizer]
The polarizing plate is mainly composed of two protective films that sandwich the polarizing film from both sides. The antireflection film of the present invention is preferably used for at least one of the two protective films sandwiching the polarizing film from both sides. Since the antireflection film of the present invention also serves as a protective film, the production cost of the polarizing plate can be reduced. Further, by using the antireflection film of the present invention as the outermost layer, reflection of external light and the like can be prevented, and a polarizing plate having excellent scratch resistance, antifouling property and the like can be obtained.

As the polarizing film, a known polarizing film or a polarizing film cut out from a long polarizing film whose absorption axis is neither parallel nor perpendicular to the longitudinal direction may be used. A long polarizing film whose absorption axis is neither parallel nor perpendicular to the longitudinal direction is produced by the following method.
That is, a polarizing film stretched by applying tension while holding both ends of a continuously supplied polymer film by a holding means, stretched at least 1.1 to 20.0 times in the film width direction, The progress of the film is such that the difference between the moving speeds in the longitudinal direction of the holding device is within 3%, and the angle formed by the film moving direction at the exit of the step of holding both ends of the film and the substantial stretching direction of the film is inclined by 20 to 70 °. The film can be produced by a stretching method in which the direction is bent while holding both ends of the film. In particular, those inclined by 45 ° are preferably used from the viewpoint of productivity.

  The method for stretching the polymer film is described in detail in paragraphs [0020] to [0030] of JP-A-2002-86554.

[Saponification]
When the antireflection film of the present invention is used in a liquid crystal display device, it is disposed on the outermost surface of the display by providing an adhesive layer on one side. Further, the antireflection film of the present invention and a polarizing plate may be used in combination. When the transparent substrate is triacetyl cellulose, triacetyl cellulose is used as a protective film for protecting the polarizing layer of the polarizing plate. Therefore, it is preferable in terms of cost to use the antireflection film of the present invention as it is for the protective film.

The antireflection film of the present invention is a transparent base material for sufficient adhesion when it is disposed on the outermost surface of a display by providing an adhesive layer on one side or used as it is as a protective film for a polarizing plate. It is preferable to carry out a saponification treatment after forming an outermost layer mainly composed of a fluorine-containing polymer. The saponification treatment is performed by a known method, for example, by immersing the film in an alkali solution for an appropriate time. After being immersed in the alkaline solution, it is preferable to sufficiently wash with water or neutralize the alkaline component by dipping in a dilute acid so that the alkaline component does not remain in the film.
By performing the saponification treatment, the surface of the transparent substrate opposite to the side having the outermost layer is hydrophilized.
The hydrophilized surface is particularly effective for improving the adhesion with a polarizing film containing polyvinyl alcohol as a main component. In addition, the hydrophilic surface makes it difficult for dust in the air to adhere to it, so that it is difficult for dust to enter between the polarizing film and the antireflection film when adhered to the polarizing film, and this prevents point defects caused by dust. It is valid.
The saponification treatment is preferably carried out so that the contact angle of water on the surface of the transparent substrate opposite to the side having the outermost layer is 40 ° or less. More preferably, it is 30 ° or less, particularly preferably 20 ° or less.

Specific means for the alkali saponification treatment can be selected from the following two means (1) and (2). (1) is superior in that it can be processed in the same process as a general-purpose triacetylcellulose film, but since the surface of the antireflection layer is saponified, the antireflection layer deteriorates due to alkali hydrolysis of the surface. The problem that the treatment liquid becomes dirty can be a problem. In that case, although it becomes a special process, (2) is excellent.
(1) After the antireflection layer is formed on the transparent substrate, the back surface of the film is saponified by immersing it in an alkaline solution at least once.
(2) Before or after the formation of the antireflection layer on the transparent substrate, the alkaline solution is applied to the surface of the antireflection film opposite to the surface on which the antireflection film is formed, and is heated, washed with water and / or inside By summing, only the back surface of the film is saponified.

[Image display device]
The image display device of the present invention is characterized in that at least one of the above-described antireflection film and polarizing plate (polarizing plate with antireflection ability) is disposed on the image display surface. The antireflection film and polarizing plate of the present invention can be applied to an image display device such as a liquid crystal display device (LCD) or an organic EL display.

  Any conventionally known liquid crystal display device can be used. For example, supervised by Tatsuo Uchida, “Reflective color LCD integrated technology” {CMC, published in 1999}, “New development of flat panel display” {Research Division, Toray Research Center, published in 1996}, “Liquid crystal related market” And the future prospects (first volume), (second volume) "{Fuji Chimera Research Institute, Inc., published in 2003}, and the like.

  The antireflection film of the present invention, when used as one side of the surface protective film of the polarizing film, is twisted nematic (TN), super twisted nematic (STN), vertical alignment (VA), in-plane switching (IPS), optical It can be preferably used for a transmissive, reflective, or transflective liquid crystal display device of a mode such as a curry compensate bend cell (OCB).

  In addition, the polarizing plate of the present invention realizes a good contrast and a wide viewing angle even when the size of the attached liquid crystal display device display image is 17 inches or more, and prevents hue change and transfer of external light. This is preferable because it has good durability.

<VA mode liquid crystal display device>
In a VA mode liquid crystal cell, rod-like liquid crystalline molecules are aligned substantially vertically when no voltage is applied.
The VA mode liquid crystal cell includes (1) a narrowly-defined VA mode liquid crystal cell in which rod-like liquid crystalline molecules are aligned substantially vertically when no voltage is applied, and substantially horizontally when a voltage is applied (Japanese Patent Laid-Open No. 2). 176625 (in Japanese Patent Publication No. 176625), and (2) a liquid crystal cell (SID97, Digest of tech. Papers (Preliminary Proceed) 28 (1997) 845 in which the VA mode is converted into a multi-domain (for MVA mode) in order to expand the viewing angle. ), (3) Liquid crystal cell in a mode (n-ASM mode) in which rod-like liquid crystalline molecules are substantially vertically aligned when no voltage is applied and twisted multi-domain alignment is applied when a voltage is applied (Preliminary collections 58-59 of the Japanese Liquid Crystal Society) (1998)) and (4) SURVAIVAL mode liquid crystal cells (announced at LCD International 98).
For a VA mode liquid crystal cell, a polarizing plate prepared by combining a triacetyl cellulose film stretched biaxially with the antireflection film of the present invention is preferably used. As for a method for producing a biaxially stretched triacetyl cellulose film, for example, the methods described in JP-A Nos. 2001-249223 and 2003-170492 are preferably used.

<OCB mode liquid crystal display device>
The OCB mode liquid crystal cell is a liquid crystal display device using a bend alignment mode liquid crystal cell in which rod-like liquid crystalline molecules are aligned in a substantially opposite direction (symmetrically) between the upper part and the lower part of the liquid crystal cell. It is disclosed in the specifications of Japanese Patent Nos. 45882525 and 5410422. Since the rod-like liquid crystal molecules are symmetrically aligned at the upper and lower portions of the liquid crystal cell, the bend alignment mode liquid crystal cell has a self-optical compensation function. Therefore, this liquid crystal mode is also referred to as an OCB (Optically Compensatory Bend) liquid crystal mode. The bend alignment mode liquid crystal display device has an advantage of high response speed.

  Similarly to the TN mode, the liquid crystal cell in the OCB mode is in a black display, and the alignment state in the liquid crystal cell is such that the rod-like liquid crystal molecules rise in the center of the cell and the rod-like liquid crystal molecules lie in the vicinity of the cell substrate. .

<TN mode liquid crystal display device>
The TN mode liquid crystal cell is most frequently used as a color TFT liquid crystal display device, and many publications are cited. The alignment state in the liquid crystal cell in the TN mode black display is an alignment state in which the rod-like liquid crystalline molecules rise at the center of the cell and the rod-like liquid crystalline molecules lie in the vicinity of the cell substrate.

  In a TN mode liquid crystal cell, rod-like liquid crystalline molecules are substantially horizontally aligned when no voltage is applied, and is most frequently used as a color TFT liquid crystal display device, and is described in many documents. For example, it is described in “EL, PDP, LCD display” published by Toray Research Center (2001).

<IPS mode liquid crystal display device>
In the IPS mode liquid crystal cell, the liquid crystal molecules are always rotated in a horizontal plane with respect to the substrate, and are aligned so as to have a slight angle with respect to the longitudinal direction of the electrode when no electric field is applied. When an electric field is applied, the liquid crystal molecules change direction in the direction of the electric field. The light transmittance can be changed by arranging the polarizing plates sandwiching the liquid crystal cell at a predetermined angle. As the liquid crystal molecules, nematic liquid crystal having a positive dielectric anisotropy Δε is used. The thickness of the liquid crystal layer is more than 2.8 μm and less than 4.5 μm. This is because when the retardation Δn · d is more than 0.25 μm and less than 0.32 μm, a transmittance characteristic having almost no wavelength dependency within the visible light range can be obtained. By combining the polarizing plates, the maximum transmittance can be obtained when the liquid crystal molecules are rotated 45 ° from the rubbing direction to the electric field direction. The thickness of the liquid crystal layer is controlled by polymer beads. Of course, the same gap can be obtained with glass bead fiber or resin columnar spacers. The liquid crystal molecules are not particularly limited as long as they are nematic liquid crystals. The larger the value of the dielectric anisotropy Δε, the lower the drive voltage, and the smaller the refractive index anisotropy Δn, the thicker the liquid crystal layer, the shorter the liquid crystal sealing time, and the liquid crystal layer Variation in thickness can be reduced.

  In particular, for a TN mode or IPS mode liquid crystal display device, as described in JP-A-2001-100043, an optical compensation film having a viewing angle expansion effect is used as a protective film having two polarizing films on both sides. Among them, by using it on the surface opposite to the antireflection film of the present invention, a polarizing plate having an antireflection effect and a viewing angle widening effect can be obtained with the thickness of one polarizing plate, which is particularly preferable.

<Other LCD mode>
For the ECB mode and STN mode liquid crystal display devices, the polarizing plate of the present invention can be provided in the same manner as described above.

<Display device>
The liquid crystal display device can be formed according to the conventional method. That is, a liquid crystal display device is generally formed by incorporating a drive circuit by appropriately combining liquid crystal cells, an optical film, and, if necessary, components such as an illumination system. In this invention, there is no limitation in particular except the point which uses the liquid crystal display element by this invention, and it can apply according to the former.

  In forming the liquid crystal display device, for example, appropriate components such as a prism array, a lens array sheet, a light scattering plate, a light guide plate, and a backlight can be arranged in one or more layers at appropriate positions. Further, by combining with a λ / 4 plate, it can be used to reduce the reflected light from the surface and inside as a polarizing plate for reflective liquid crystal or a surface protective plate for organic EL display.

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the scope of the present invention should not be construed as being limited thereto.
In this embodiment, “part” means “part by mass”.

(Embodiment of layer forming method (I))
[Example A-1]
(Preparation of coating solution for hard coat layer)
The following composition was put into a mixing tank and stirred to obtain a hard coat layer coating solution.
750.0 parts by weight of trimethylolpropane triacrylate (Biscoat # 295 (manufactured by Osaka Organic Chemical Co., Ltd.)), 270.0 parts by weight of polyglycidyl methacrylate having a mass average molecular weight of 15000, 730.0 parts by weight of methyl ethyl ketone, 500.0 cyclohexanone Mass parts and 50.0 parts by mass of a photopolymerization initiator (Irgacure 184, manufactured by Ciba Specialty Chemicals Co., Ltd.) were added and stirred, and filtered through a polypropylene filter having a pore size of 0.4 μm for the hard coat layer. A polyglycidyl methacrylate was prepared by dissolving glycidyl methacrylate in methyl ethyl ketone (MEK) and reacting at 80 ° C. for 2 hours while adding a thermal polymerization initiator (V-65 (manufactured by Wako Pure Chemical Industries, Ltd.)). The obtained reaction solution was dropped into hexane, and the precipitate was Obtained by pressure dry.

(Preparation of titanium dioxide fine particle dispersion)
As the titanium dioxide fine particles, titanium dioxide fine particles (MPT-129C, manufactured by Ishihara Sangyo Co., Ltd., TiO ₂ : Co ₃ O ₄ : containing cobalt and surface-treated with aluminum hydroxide and zirconium hydroxide: Al ₂ O ₃ : ZrO ₂ = 90.5: 3.0: 4.0: 0.5 weight ratio) was used.
The following dispersant (41.1 parts by mass) and cyclohexanone (701.8 parts by mass) were added to 257.1 parts by mass of the particles and dispersed by dynomill to prepare a titanium dioxide dispersion having a weight average diameter of 70 nm.

Dispersant

(Preparation of coating solution for medium refractive index layer)
In 99.1 parts by mass of the above titanium dioxide dispersion, 68.0 parts by mass of a mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (DPHA, manufactured by Nippon Kayaku Co., Ltd.), a photopolymerization initiator (Irgacure 907) 3.6 parts by mass, manufactured by Ciba Specialty Chemicals Co., Ltd., 1.2 parts by mass of photosensitizer (Kayacure DETX, manufactured by Nippon Kayaku Co., Ltd.), 279.6 parts by mass of methyl ethyl ketone, and 1049.0 of cyclohexanone. A part by mass was added and stirred. After sufficiently stirring, the solution was filtered through a polypropylene filter having a pore diameter of 0.4 μm to prepare a coating solution for a medium refractive index layer.

(Preparation of coating solution for high refractive index layer)
To 469.8 parts by mass of the above titanium dioxide dispersion, 40.0 parts by mass of a mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (DPHA, Nippon Kayaku Co., Ltd.), a photopolymerization initiator (Irgacure 907) 3.3 parts by mass, manufactured by Ciba Specialty Chemicals Co., Ltd., 1.1 parts by mass of photosensitizer (Kayacure-DETX, manufactured by Nippon Kayaku Co., Ltd.), 526.2 parts by mass of methyl ethyl ketone, and cyclohexanone 459 .6 parts by mass was added and stirred. The solution was filtered through a polypropylene filter having a pore diameter of 0.4 μm to prepare a coating solution for a high refractive index layer.

(Preparation of coating solution for low refractive index layer)
The copolymer P-3 described in the present text was dissolved in methyl isobutyl ketone (MIBK) to a concentration of 7% by mass, and a terminal methacrylate group-containing silicone resin X-22-164C (manufactured by Shin-Etsu Chemical Co., Ltd.) was solidified. The photo-radical generator Irgacure OXE01 (trade name) was added at 5% by mass with respect to the solid content to prepare a coating solution for a low refractive index layer.

(Preparation of antireflection film 101)
A hard coat layer coating solution was applied onto a triacetyl cellulose film (TD80UF, manufactured by Fuji Photo Film Co., Ltd.) having a thickness of 80 μm using a gravure coater. After drying at 100 ° C., an irradiance of 400 mW / cm using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) of 160 W / cm while purging with nitrogen so that the oxygen concentration becomes 1.0 vol% or less. ^{2. The} coating layer was cured by irradiating ultraviolet rays with an irradiation amount of 300 mJ / cm ² to form a hard coat layer having a thickness of 8 μm.
On the hard coat layer, a medium refractive index layer coating solution, a high refractive index layer coating solution, and a low refractive index layer coating solution were successively applied using a gravure coater having three coating stations.

The medium refractive index layer was dried at 90 ° C. for 30 seconds, and the ultraviolet curing condition was 180 W / cm air-cooled metal halide lamp (eye graphics) while purging with nitrogen so that the atmosphere had an oxygen concentration of 1.0% by volume or less. ), And the irradiation dose was 400 mW / cm ² and the irradiation dose was 400 mJ / cm ² .
The medium refractive index layer after curing had a refractive index of 1.630 and a film thickness of 67 nm.

The drying condition of the high refractive index layer is 90 ° C. for 30 seconds, and the ultraviolet curing condition is a 240 W / cm air-cooled metal halide lamp (eye graphics) while purging with nitrogen so that the atmosphere has an oxygen concentration of 1.0% by volume or less. ), And the irradiation dose was 600 mW / cm ² and the irradiation dose was 400 mJ / cm ² .
The cured high refractive index layer had a refractive index of 1.905 and a film thickness of 107 nm.

The drying conditions for the low refractive index layer were 90 ° C. and 30 seconds. The UV curing conditions were as follows: an air cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) having an illuminance of 600 mW / cm ² while purging with nitrogen so that the atmosphere had an oxygen concentration of 0.1% by volume or less. The irradiation dose was 600 mJ / cm ² .
The low refractive index layer after curing had a refractive index of 1.440 and a film thickness of 85 nm. Thus, the antireflection film 101 was produced.
Only the curing conditions of the low refractive index layer were changed to the conditions shown in Table 1, and Samples 102 to 112 were produced. In the case of heating after ultraviolet irradiation, the film after irradiation was brought into contact with a rotating metal roll through which hot water or pressurized steam was passed. In addition, the film temperature in the sample which is not heated (for example, sample 101) is based on the reaction heat at the time of ultraviolet irradiation.

The following items were evaluated for the obtained film. The results are shown in Table 2.
[Specular reflectance]
An adapter ARV-474 is attached to a spectroscopic hardness meter V-550 (manufactured by JASCO Corporation), and the specular reflectance at an incident angle of -5 degrees is measured at an incident angle of 5 degrees in a wavelength range of 380 to 780 nm. The average reflectance at 650 nm was calculated and the antireflection property was evaluated.
[Pencil hardness]
The pencil hardness evaluation described in JIS K 5400 was performed. After conditioning the antireflection film at a temperature of 25 ° C. and a humidity of 60% RH for 2 hours, it was evaluated using the H-5H test pencil specified in JIS S 6006 at a load of 500 g as follows. The highest hardness that results in OK was taken as the evaluation value.
In evaluation of n = 5, there is no scratch to one scratch: OK
In evaluation of n = 5, 3 or more scratches: NG

[Steel wool scuff resistance]
The state of scratches was observed when a load of 1.96 N / cm ² was applied to steel steel of # 0000 and reciprocated 30 times, and the following five stages were evaluated.
◎: Scratch not found ○: Slightly invisible scratch △: Clearly visible scratch ×: Clearly visible scratch XX: Delamination of the film occurred thing

From the formation conditions of the present invention, it can be seen that the antireflection film of the present invention is excellent in scratch resistance while having sufficient antireflection performance. The post-heating time is preferably 0.1 seconds or longer.
Further, in the present invention, stable performance can be ensured even if the oxygen concentration and irradiation amount at the time of ultraviolet irradiation are varied.

[Example A-2]
In the preparation methods of Samples 102, 103, 104, 105, 108, and 109 of Example A-1, samples 113 to 118 that differ only in passing through a nitrogen-substituted zone before the ultraviolet irradiation zone were prepared, and the same evaluation was performed. went. Samples 119 and 120 differ from each other only in passing through a nitrogen-substituted zone before the ultraviolet irradiation zone in the method for producing the sample 105 in Example A-1.
In the case of heating after ultraviolet irradiation, the film after irradiation was brought into contact with a rotating metal roll through which hot water or pressurized steam was passed.

The results are shown in Table 4. By passing through a low oxygen concentration nitrogen substitution zone before ultraviolet irradiation, an improvement in scratch resistance is observed. Curing became significant when combined with the step of passing through a heated nitrogen substitution zone with low oxygen concentration after UV irradiation.
In addition, it was confirmed that the scratch resistance was improved by heating a low oxygen concentration nitrogen-substituted zone before ultraviolet irradiation.

[Example A-3]
As a result of performing the same evaluation by changing the fluorine-containing polymer used in the low refractive index layer in Examples A-1 and A-2 to P-1 and P-2 described in the text (replacement with equal mass), Example A-1 The same effect as in ˜2 was obtained.

[Example A-4]
(Preparation of coating solution for hard coat layer)
The following composition was put into a mixing tank and stirred to obtain a hard coat layer coating solution.
───────────────────────────────────
Coating composition for hard coat layer ───────────────────────────────────
Desolite Z7404 (Zirconia fine particle-containing hard coat composition liquid: solid content concentration 60
wt%, zirconia fine particle content 70 wt% vs. solid content, average particle size about 20 nm, solvent composition M
IBK: MEK = 9: 1, including initiator, manufactured by JSR Corporation)
100 parts by mass DPHA (UV curable resin: manufactured by Nippon Kayaku Co., Ltd.) 31 parts by mass KBM-5103 (silane coupling agent: manufactured by Shin-Etsu Chemical Co., Ltd.)
10 parts by mass KE-P150 (1.5 μm silica particles: manufactured by Nippon Shokubai Co., Ltd.)
8.9 parts by mass MXS-300 (3 μm crosslinked PMMA particles: manufactured by Soken Chemical Co., Ltd.)
3.4 parts by mass MEK 29 parts by mass MIBK 13 parts by mass ───────────────────────────────────

(Preparation of coating solution for low refractive index layer)
A coating solution for a low refractive index layer was prepared in the same manner as in Example A-1.

(Preparation of antireflection film 401)
A triacetyl cellulose film (TD80U, manufactured by Fuji Photo Film Co., Ltd.) is rolled out as a transparent substrate, and the above hard coat layer coating solution has a gravure pattern of 135 lines / inch and a depth of 60 μm. Using a micro gravure roll with a diameter of 50 mm and a doctor blade, it was applied at a transfer speed of 10 m / min, dried at 60 ° C. for 150 seconds, and further under a nitrogen purge, a 160 W / cm air-cooled metal halide lamp (eye graphics ( using Ltd.)), illuminance 400 mW / cm ^2, thereby curing the coated layer by an irradiation dose of 250 mJ / cm ^2, to form a hard coat layer it was wound. After curing, the gravure roll rotation speed was adjusted so that the thickness of the hard coat layer was 3.6 μm.

The transparent base material coated with the hard coat layer was unwound again, and the coating liquid for the low refractive index layer was coated with a microgravure roll having a diameter of 200 lines / inch and a gravure pattern having a depth of 30 μm and a diameter of 50 mm and a doctor blade. Using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) with an oxygen concentration of 0.1% by volume after applying for 30 seconds at 90 ° C. and applying at a conveyance speed of 10 m / min. It was used to irradiate ultraviolet rays having an illuminance of 600 mW / cm ² and an irradiation amount of 400 mJ / cm ² to form a low refractive index layer and wind it up. After curing, the rotation speed of the gravure roll was adjusted so that the thickness of the low refractive index layer was 100 nm. In the case of heating after ultraviolet irradiation, the film after irradiation was brought into contact with a rotating metal roll through which hot water or pressurized steam was passed.
Samples 402 to 412 were prepared by changing the curing conditions of the low refractive index layer as shown in Table 5.

These samples were evaluated in the same manner as in Example A-1. The results are shown in Table 6.
It can be seen that the formation method of the present invention provides an antireflection film having excellent scratch resistance while maintaining antireflection performance.

[Example A-5]
In the production methods of Samples 402, 403, 404, 405, 408, and 409 of Example A-4, Samples 413 to 418 that differ only in passing through a nitrogen-substituted zone before the ultraviolet irradiation zone were produced, and the same evaluation was performed. Went. Samples 419 and 420 differ from each other only in passing through a nitrogen-substituted zone before the ultraviolet irradiation zone in the method for producing the sample 405 of Example A-3.

  The results are shown in Table 8. By passing through a low oxygen concentration nitrogen substitution zone before ultraviolet irradiation, an improvement in scratch resistance is observed. Further, the curing becomes remarkable by combining with a process of passing through a heated nitrogen substitution zone having a low oxygen concentration after ultraviolet irradiation.

[Example A-6]
When the antireflective film which changed the coating liquid for low refractive index layers of Examples A-1 to 5 into the following coating liquids A and B for low refractive index layers was produced and evaluated, the same effects of the present invention were obtained. Was confirmed.
By using the hollow silica fine particles, it was possible to produce a low-reflectance antireflection film having further excellent scratch resistance.

(Preparation of sol solution a)
A stirrer, a reactor equipped with a reflux condenser, 120 parts of methyl ethyl ketone, 100 parts of acryloyloxypropyltrimethoxysilane (KBM-5103, manufactured by Shin-Etsu Chemical Co., Ltd.), diisopropoxyaluminum ethyl acetoacetate (trade name: Kerope EP) -12, manufactured by HOPE PHARMACEUTICAL CO., LTD.) After mixing, 30 parts of ion-exchanged water was added and reacted at 60 ° C. for 4 hours, followed by cooling to room temperature to obtain sol solution a. The mass average molecular weight was 1600, and among the components higher than the oligomer component, the component having a molecular weight of 1000 to 20000 was 100%. Further, from the gas chromatography analysis, the raw material acryloyloxypropyltrimethoxysilane did not remain at all.

(Preparation of hollow silica fine particle dispersion)
Hollow silica fine particle sol (Isopropyl alcohol silica sol, CS60-IPA manufactured by Catalyst Chemical Industry Co., Ltd., average particle diameter 60 nm, shell thickness 10 nm, silica concentration 20%, silica particle refractive index 1.31) in 500 parts, acryloyloxypropyl After adding and mixing 30 parts of trimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., KBM-5103) and 1.5 parts of diisopropoxyaluminum ethyl acetate (trade name: Kellop EP-12, manufactured by Hope Pharmaceutical Co., Ltd.) Nine parts of ion-exchanged water was added. After making it react at 60 degreeC for 8 hours, it cooled to room temperature and added 1.8 parts of acetylacetone, and obtained the hollow silica dispersion liquid. The resulting hollow silica dispersion had a solid content concentration of 18% by mass and a refractive index after solvent drying of 1.31.

(Preparation of coating solution A for low refractive index layer)
───────────────────────────────────
Composition A for low refractive index layer ───────────────────────────────────
DPHA 3.3g
Hollow silica fine particle dispersion 40.0g
RMS-033 0.7g
Irgacure OXE01 0.2g
Sol liquid a 6.2g
Methyl ethyl ketone 290.6g
Cyclohexanone 9.0g
───────────────────────────────────

(Preparation of coating solution B for low refractive index layer)
───────────────────────────────────
Composition B for low refractive index layer ───────────────────────────────────
DPHA 1.4g
Copolymer P-3 5.6 g
Hollow silica fine particle dispersion 20.0g
RMS-033 0.7g
Irgacure OXE01 0.2g
Sol liquid a 6.2g
Methyl ethyl ketone 306.9g
Cyclohexanone 9.0g
───────────────────────────────────

The compounds used are shown below.
KBM-5103: Silane coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd.).
DPHA: A mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (manufactured by Nippon Kayaku Co., Ltd.)
RMS-033: Reactive silicone (manufactured by Gelest Co., Ltd.)
Irgacure OXE01: Photopolymerization initiator (manufactured by Ciba Specialty Chemicals)

[Example A-7]
When the antireflective film which changed the coating liquid for low refractive index layers of Examples A-1 to 5 into the following coating liquid C for low refractive index layers was produced and evaluated, the same effects of the present invention were obtained. It could be confirmed. The same effect was also obtained with a low refractive index layer in which Opstar JN7228A was replaced with JTA113 (manufactured by JSR Co., Ltd.) having an increased degree of cross-linking with equal mass.

(Preparation of coating solution C for low refractive index layer)
The following composition was put into a mixing tank, stirred, and then filtered through a polypropylene filter having a pore size of 1 μm to prepare a coating solution C for a low refractive index layer.
───────────────────────────────────
Coating C solution composition for low refractive index layer ───────────────────────────────────
OPSTAR JN7228A (thermally crosslinkable fluorine-containing polymer composition liquid containing polysiloxane and hydroxyl group, manufactured by JSR Corporation)
100 parts by mass MEK-ST (silica dispersion, average particle size 15 nm, manufactured by Nissan Chemical Co., Ltd.)
4.3 parts by mass MEK-ST with different particle size (silica dispersion, average particle size 45 nm, manufactured by Nissan Chemical Co., Ltd.)
5.1 parts by mass Sol solution a 2.2 parts by mass MEK 15 parts by mass cyclohexanone 3.6 parts by mass ─────────────────────────── ────────

  The low-refractive-index layer coating solution is applied at a conveyance speed of 10 m / min using a micro gravure roll having a diameter of 200 lines / inch and a gravure pattern with a depth of 30 μm and a doctor blade at a conveyance speed of 10 m / min. After drying for 150 seconds, the sample was further dried at 140 ° C. for 12 minutes, and then irradiated with ultraviolet rays described in Example A-1 to prepare a sample. The rotation speed of the gravure roll was adjusted so that the thickness of the low refractive index layer after curing was 100 nm.

[Example A-8]
(Preparation of protective film for polarizing plate)
A saponification solution in which a 1.5 mol / L sodium hydroxide aqueous solution was kept at 50 ° C. was prepared.
Furthermore, a 0.005 mol / L dilute sulfuric acid aqueous solution was prepared.
In the antireflection films prepared in Examples A-1 to A-7, the surface of the transparent substrate opposite to the side having the cured layer of the present invention was saponified using the saponification solution.
The aqueous sodium hydroxide solution on the surface of the saponified transparent substrate is thoroughly washed with water, then washed with the above diluted sulfuric acid aqueous solution, and further, the diluted sulfuric acid aqueous solution is thoroughly washed with water and sufficiently dried at 100 ° C. It was.
When the contact angle of the surface of the saponified transparent substrate on the side opposite to the side having the hardened layer of the antireflection film was evaluated, it was 40 degrees or less. Thus, the protective film for polarizing plates was produced.

[Example A-9]
(Preparation of polarizing plate)
A polyvinyl alcohol film having a thickness of 75 μm (manufactured by Kuraray Co., Ltd.) was immersed in an aqueous solution consisting of 1000 parts by mass of water, 7 parts by mass of iodine, and 105 parts by mass of potassium iodide to adsorb iodine.
Subsequently, this film was uniaxially stretched 4.4 times in the longitudinal direction in a 4% by mass boric acid aqueous solution, and then dried in a tension state to produce a polarizing film.
Saponification of the antireflection film (protective film for polarizing plate) produced in Examples A-1 to 7 which was saponified in Example A-8 on one surface of the polarizing film using a polyvinyl alcohol-based adhesive as an adhesive The treated triacetyl cellulose surface was bonded. Further, a triacetyl cellulose film saponified in the same manner as described above was bonded to the other surface of the polarizing film using the same polyvinyl alcohol-based adhesive.

(Evaluation of image display device)
The TN, STN, IPS, VA, OCB mode transmission type, reflection type, or transflective type in which the polarizing plate of the present invention thus prepared is mounted so that the antireflection film is the outermost surface of the display. The liquid crystal display device was excellent in antireflection performance and extremely excellent in visibility. In particular, the effect is remarkable in the VA mode.

[Example A-10]
(Preparation of polarizing plate)
In the optical compensation film (Wide View Film SA 12B, manufactured by Fuji Photo Film Co., Ltd.), the surface opposite to the side having the optical compensation layer was saponified under the same conditions as in Example A-8. The polarizing film prepared in Example A-9 was prepared in Examples A-1 to 7 which were saponified in Example A-8 on one surface of the polarizing film using a polyvinyl alcohol adhesive as an adhesive. The anti-reflection film (protective film for polarizing plate) of saponified triacetyl cellulose was bonded to each other. Further, the triacetyl cellulose surface of the saponified optical compensation film was bonded to the other surface of the polarizing film using the same polyvinyl alcohol adhesive.

(Evaluation of image display device)
The TN, STN, IPS, VA, OCB mode transmission type, reflection type, or transflective type in which the polarizing plate of the present invention thus prepared is mounted so that the antireflection film is the outermost surface of the display. The liquid crystal display device has better contrast in the bright room than the liquid crystal display device equipped with a polarizing plate that does not use an optical compensation film, has a very wide viewing angle in the vertical and horizontal directions, and has excellent antireflection performance and extremely high visibility. The display and display quality were excellent.
In particular, the effect is remarkable in the VA mode.

[Example A-11]
In the production method of the antireflection film 108, the coating solution formulation of the low refractive index layer was changed to LL-61 below, and coating was performed at a coating speed of 25 m / min using the following die coater. Then, after drying at 90 ° C. for 30 seconds, using a 240 W / cm air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) while purging with nitrogen so that the atmosphere has an oxygen concentration of 0.1% by volume or less, An ultraviolet ray having an illuminance of 600 mW / cm ² and an irradiation amount of 400 mJ / cm ² was irradiated to form a low refractive index layer (refractive index 1.45, film thickness 83 nm). In this way, an antireflection film (11-1) was produced.
Furthermore, antireflection films (11-2) to (11-5) were produced by changing the low refractive index layer coating solution to LL-62 to 65.

(Die coater configuration)
The slot die 13 has an upstream lip land length I _UP of 0.5 mm, a downstream lip land length I _LO of 50 μm, a length of the opening of the slot 16 in the web running direction of 150 μm, and a length of the slot 16 of 50 mm. I used one. The gap between the upstream lip land 18a and the web is made 50 μm longer than the gap between the downstream lip land 18b and the web (hereinafter referred to as an overbite length of 50 μm), and the gap _GL between the downstream lip land 18b and the web is The thickness was set to 50 μm. Further, the gap G _S between the side plate 40b and the web of the decompression chamber 40, and the gap G _B between the back plate 40a and the web were both 200 [mu] m.

(Preparation of coating solution for low refractive index layer (LL-61))
152.4 parts by mass of a solution obtained by dissolving the copolymer P-3 described in this text in methyl ethyl ketone so as to have a concentration of 23.7% by mass, a terminal methacrylate group-containing silicone resin X-22-164C (manufactured by Shin-Etsu Chemical Co., Ltd.) ) 1.1 parts by weight, 1.8 parts by weight of photo radical generator Irgacure 1870 (manufactured by Ciba Specialty Chemicals), 815.9 parts by weight of methyl ethyl ketone, and 28.8 parts by weight of cyclohexanone were added and stirred. . The mixture was filtered through a PTFE filter having a pore diameter of 0.45 μm to prepare a coating solution for low refractive index layer (LL-61). The viscosity of the coating solution was 0.61 [mPa · sec], the surface tension was 24 [mN / m], and the amount of the coating solution applied to the transparent substrate was 2.8 [ml / m ² ]. .

(Preparation of coating solution for low refractive index layer (LL-62))
426.6 parts by mass of a solution obtained by dissolving the above copolymer P-3 in methyl ethyl ketone so as to have a concentration of 23.7% by mass, terminal methacrylate group-containing silicone resin X-22-164C (manufactured by Shin-Etsu Chemical Co., Ltd.) 3.0 parts by mass, 5.1 parts by mass of photoradical generator Irgacure 1870 (manufactured by Ciba Specialty Chemicals Co., Ltd.), 538.6 parts by mass of methyl ethyl ketone, and 26.7 parts by mass of cyclohexanone were added and stirred. The mixture was filtered through a PTFE filter having a pore diameter of 0.45 μm to prepare a coating solution for low refractive index layer (LL-62). The viscosity of the coating solution was 1.0 [mPa · sec], the surface tension was 24 [mN / m], and the amount of the coating solution applied to the transparent substrate was 1.5 [ml / m ² ]. .

(Preparation of coating solution for low refractive index layer (LL-63))
213.3 parts by mass of a solution obtained by dissolving the above copolymer P-3 in methyl ethyl ketone to a concentration of 23.7% by mass, terminal methacrylate group-containing silicone resin X-22-164C (manufactured by Shin-Etsu Chemical Co., Ltd.) 1.5 parts by mass, 2.5 parts by mass of photoradical generator Irgacure 1870 (manufactured by Ciba Specialty Chemicals), 754.3 parts by mass of methyl ethyl ketone, and 28.4 parts by mass of cyclohexanone were added and stirred. The mixture was filtered through a PTFE filter having a pore diameter of 0.45 μm to prepare a coating solution for low refractive index layer (LL-63). The viscosity of the coating solution was 0.76 [mPa · sec], the surface tension was 24 [mN / m], and the amount of the coating solution applied to the transparent substrate was 2.0 [ml / m ² ]. .

(Preparation of coating solution for low refractive index layer (LL-64))
85.3 parts by mass of a solution obtained by dissolving the above copolymer P-3 in methyl ethyl ketone so as to have a concentration of 23.7% by mass, terminal methacrylate group-containing silicone resin X-22-164C (manufactured by Shin-Etsu Chemical Co., Ltd.) 0.6 parts by mass, 1.0 part by mass of photoradical generator Irgacure 1870 (manufactured by Ciba Specialty Chemicals), 883.7 parts by mass of methyl ethyl ketone, and 29.3 parts by mass of cyclohexanone were added and stirred. The mixture was filtered through a PTFE filter having a pore diameter of 0.45 μm to prepare a coating solution for low refractive index layer (LL-64). The viscosity of the coating solution was 0.49 [mPa · sec], the surface tension was 24 [mN / m], and the amount of the coating solution applied to the transparent substrate was 5.0 [ml / m ² ]. .

(Preparation of coating solution for low refractive index layer (LL-65))
71.1 parts by mass of a solution obtained by dissolving the above copolymer P-3 in methyl ethyl ketone so as to have a concentration of 23.7% by mass, a terminal methacrylate group-containing silicone resin X-22-164C (manufactured by Shin-Etsu Chemical Co., Ltd.) 0.5 parts by mass, 0.8 parts by mass of photoradical generator Irgacure 907 (manufactured by Ciba Specialty Chemicals Co., Ltd.), 898.1 parts by mass of methyl ethyl ketone, and 29.5 parts by mass of cyclohexanone were added and stirred. The mixture was filtered through a PTFE filter having a pore diameter of 0.45 μm to prepare a coating solution for low refractive index layer (LL-65). The viscosity of the coating solution was 0.46 [mPa · sec], the surface tension was 24 [mN / m], and the amount of the coating solution applied to the transparent substrate was 6.0 [ml / m ² ]. .

The surface shapes of the antireflection films (11-1) to (11-5) prepared by changing the coating solution for the low refractive index layer to LL-61 to LL-65 were evaluated. The results are shown in Table 9. When the amount of the coating solution applied to the transparent substrate is 2 ml / m ² or more, the coating solution can be applied. However, when the amount is 1.5 ml / m ² , the entire surface cannot be applied uniformly, and an antireflection film is created. I couldn't. In addition, when the amount of the coating solution applied to the transparent substrate is 6 ml / m ² , the coating is possible, but since the amount of the coating solution is large, drying is not in time, and vertical streaky unevenness caused by the wind. Occurred on the entire surface.
When the display apparatus was produced for the obtained antireflection film (11-1), (11-3), (11-4) in the same procedure as Example A-10, Example A- produced with a gravure coater There was less color unevenness than the 10 display devices, and the quality was high.

[Example A-12]
Antireflection films (12-1) to (12-4) were produced in the same manner as the antireflection film (11-1) except that the downstream lip land length I _L0 was 10 μm, 30 μm, 100 μm, and 120 μm. The results are shown in Table 10. When the length of the downstream lip land is in the range of 30 μm to 100 μm, an antireflection film free from surface failure can be obtained. In the antireflection film (12-1), streaky unevenness occurs in the longitudinal direction of the base, and the antireflection film (12-4) cannot form the beads 14a at the same speed as the antireflection film (11-1). Application was impossible. Application was possible by reducing the application speed to half, but streaky irregularities occurred in the longitudinal direction of the base. When the antireflection films (12-2) and (12-3) were produced by the same procedure as in Example A-10, the background reflection was very small, and the color of the reflected light was significantly reduced. Furthermore, a display device with very high display quality in which uniformity within the display surface was ensured was obtained. On the other hand, when an antireflection film obtained from the antireflection films (12-1) and (12-4) is prepared in the same procedure as in Example A-10, uneven coloring is visually recognized in the display device. I couldn't say it was high quality.

[Example A-13]
Coating was performed in the same manner as (11-1) except that the overcoat length LO of the die coater was 0 μm, 30 μm, 120 μm, and 150 μm, and antireflection films (13-1) to (13-4) were produced. . The results are shown in Table 11. When the overbite length is in the range of 30 μm to 120 μm, an antireflection film free from surface defects can be obtained. Application was possible with the antireflection film (13-1), but stepped unevenness was recognized in the base width direction when the surface shape was seen. Further, in the antireflection film (13-4), the beads 14a could not be formed at the same speed as (13-1), and the coating was impossible. Application was possible by reducing the application speed to half, but streaky irregularities occurred in the longitudinal direction of the base. In the antireflection films (13-2) and (13-3), when a display device was prepared in the same procedure as in Example A-10, the reflection of the background was extremely small, and the color of the reflected light was significantly reduced. Furthermore, a display device with very high display quality in which uniformity within the display surface was ensured was obtained. On the other hand, when a display device is prepared with the antireflection films (13-1) and (13-4) in the same procedure as in Example A-10, uneven coloring is visually recognized in the display device, which cannot be said to be high quality. It was.

  The curing conditions for preparing 11-1, 3 and 4 in Table 9 are shown in Sample No. Even if it changed to 105-107, 111, and 112, respectively, the evaluation result of the obtained film was not different from the result of Table 9, Table 10, and Table 11.

(Embodiment of layer forming method (II))
[Example B-1]
(Preparation of coating solution for hard coat layer)
The following composition was put into a mixing tank and stirred to obtain a hard coat layer coating solution.
750.0 parts by weight of trimethylolpropane triacrylate (Biscoat # 295, manufactured by Osaka Organic Chemical Co., Ltd.), 270.0 parts by weight of polyglycidyl methacrylate having a mass average molecular weight of 15000, 730.0 parts by weight of methyl ethyl ketone, 500.0 cyclohexanone 50.0 parts by mass and 50.0 parts by mass of a photopolymerization initiator (Irgacure 184, manufactured by Ciba Specialty Chemicals Co., Ltd.) were added and stirred. The solution was filtered through a polypropylene filter having a pore size of 0.4 μm to prepare a coating solution for a hard coat layer. Polyglycidyl methacrylate is obtained by dissolving glycidyl methacrylate in methyl ethyl ketone (MEK) and reacting at 80 ° C. for 2 hours while adding a thermal polymerization initiator (V-65 (manufactured by Wako Pure Chemical Industries, Ltd.)). The solution was added dropwise to hexane, and the precipitate was dried under reduced pressure.

(Preparation of titanium dioxide fine particle dispersion)
As the titanium dioxide fine particles, titanium dioxide fine particles (MPT-129C, manufactured by Ishihara Sangyo Co., Ltd., TiO ₂ : Co ₃ O ₄ : containing cobalt and surface-treated with aluminum hydroxide and zirconium hydroxide: Al ₂ O ₃ : ZrO ₂ = 90.5: 3.0: 4.0: 0.5 weight ratio) was used.
The following dispersant (41.1 parts by mass) and cyclohexanone (701.8 parts by mass) were added to 257.1 parts by mass of the particles and dispersed by dynomill to prepare a titanium dioxide dispersion having a weight average diameter of 70 nm.
<Dispersant>

(Preparation of coating solution for medium refractive index layer)
In 99.1 parts by mass of the above titanium dioxide dispersion, 68.0 parts by mass of a mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (DPHA, manufactured by Nippon Kayaku Co., Ltd.), a photopolymerization initiator (Irgacure 907) 3.6 parts by mass, manufactured by Ciba Specialty Chemicals Co., Ltd., 1.2 parts by mass of photosensitizer (Kayacure DETX, manufactured by Nippon Kayaku Co., Ltd.), 279.6 parts by mass of methyl ethyl ketone, and 1049.0 of cyclohexanone. A part by mass was added and stirred. After sufficiently stirring, the solution was filtered through a polypropylene filter having a pore diameter of 0.4 μm to prepare a coating solution for a medium refractive index layer.

(Preparation of coating solution for high refractive index layer)
To 469.8 parts by mass of the above titanium dioxide dispersion, 40.0 parts by mass of a mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (DPHA, Nippon Kayaku Co., Ltd.), a photopolymerization initiator (Irgacure 907) 3.3 parts by mass, manufactured by Ciba Specialty Chemicals Co., Ltd., 1.1 parts by mass of photosensitizer (Kayacure-DETX, manufactured by Nippon Kayaku Co., Ltd.), 526.2 parts by mass of methyl ethyl ketone, and cyclohexanone 459 .6 parts by mass was added and stirred. The solution was filtered through a polypropylene filter having a pore diameter of 0.4 μm to prepare a coating solution for a high refractive index layer.

(Preparation of coating solution for low refractive index layer)
A copolymer P-3 described in JP-A-2004-45462 is dissolved in methyl isobutyl ketone so as to have a concentration of 7% by mass, and a terminal methacrylate group-containing silicone resin X-22-164C (manufactured by Shin-Etsu Chemical Co., Ltd.) ) 3% based on the solid content and 5% by mass of the above-mentioned photoradical generator Irgacure 907 (manufactured by Ciba Specialty Chemicals Co., Ltd.) based on the solid content to prepare a coating solution for a low refractive index layer. .

(Preparation of antireflection film 101)
A hard coat layer coating solution was applied onto a triacetyl cellulose film (TD80UF, manufactured by Fuji Photo Film Co., Ltd.) having a thickness of 80 μm using a gravure coater. After drying at 100 ° C., an irradiance of 400 mW / cm using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) of 160 W / cm while purging with nitrogen so that the oxygen concentration becomes 1.0 vol% or less. ^{2. The} coating layer was cured by irradiating ultraviolet rays with an irradiation amount of 300 mJ / cm ² to form a hard coat layer having a thickness of 8 μm.
On the hard coat layer, a medium refractive index layer coating solution, a high refractive index layer coating solution, and a low refractive index layer coating solution were successively applied using a gravure coater having three coating stations.

The medium refractive index layer was dried at 90 ° C. for 30 seconds, and the ultraviolet curing condition was 180 W / cm air-cooled metal halide lamp (eye graphics) while purging with nitrogen so that the atmosphere had an oxygen concentration of 1.0% by volume or less. ), And the irradiation dose was 400 mW / cm ² and the irradiation dose was 400 mJ / cm ² .
The medium refractive index layer after curing had a refractive index of 1.630 and a film thickness of 67 nm.

The drying condition of the high refractive index layer is 90 ° C. for 30 seconds, and the ultraviolet curing condition is a 240 W / cm air-cooled metal halide lamp (eye graphics) while purging with nitrogen so that the atmosphere has an oxygen concentration of 1.0% by volume or less. ), And the irradiation dose was 600 mW / cm ² and the irradiation dose was 400 mJ / cm ² .
The cured high refractive index layer had a refractive index of 1.905 and a film thickness of 107 nm.

The low refractive index layer was dried at 90 ° C. for 30 seconds, and the ultraviolet curing condition was 240 W / cm air-cooled metal halide lamp (eye graphics) while purging with nitrogen so that the atmosphere had an oxygen concentration of 0.1% by volume or less. ), And the irradiation amount was 600 mW / cm ² and the irradiation amount was 600 mJ / cm ² .
The low refractive index layer after curing had a refractive index of 1.440 and a film thickness of 85 nm. Thus, the antireflection film 101 was produced.
Only the curing conditions of the low refractive index layer were changed to the conditions shown in Table 12, and Samples 102 to 116 were produced. In the case of heating after ultraviolet irradiation, the film after irradiation was brought into contact with a rotating metal roll through which hot water or pressurized steam was passed.

The following items were evaluated for the obtained film. The results are shown in Table 13.
[Specular reflectance]
An adapter ARV-474 is attached to a spectroscopic hardness meter V-550 (manufactured by JASCO Corp.), and a specular reflectance at an incident angle of -5 degrees is measured at an incident angle of 5 degrees in a wavelength range of 380 to 780 nm. The average reflectance at 650 nm was calculated and the antireflection property was evaluated.
[Pencil hardness]
The pencil hardness evaluation described in JIS K 5400 was performed. After conditioning the antireflection film at a temperature of 25 ° C. and a humidity of 60% RH for 2 hours, it was evaluated using the H-5H test pencil specified in JIS S 6006 at a load of 500 g as follows. The highest hardness that results in OK was taken as the evaluation value.
In evaluation of n = 5, there is no scratch to one scratch: OK
In evaluation of n = 5, 3 or more scratches: NG

[Steel wool scuff resistance]
The state of scratches was observed when a load of 1.96 N / cm ² was applied to steel steel of # 0000 and reciprocated 30 times, and the following five stages were evaluated.
◎: Scratch not found ○: Slightly invisible scratch △: Clearly visible scratch ×: Clearly visible scratch XX: Delamination of the film occurred thing

[In-plane uniformity]
20 points were taken from the prepared sample 1m ² , the steel wool rubbing resistance was tested, and the variation was evaluated in the following three stages.
○: The variation was within 0.5 rank △: The variation was 1 rank ×: The variation was 1 rank or more
[Dimensional change]
In order to estimate the dimensional change, which is the cause of wrinkles, the change rate (%) of the length in the width direction of the sample when left for 12 hours at the temperature at the time of each UV irradiation was estimated.
[Surface]
The surface shape of the film surface was observed visually.

According to the curing conditions of the present invention, it was found that the antireflection film of the present invention was excellent in scratch resistance while having sufficient antireflection performance. When the temperature after UV irradiation was high, the uniformity of in-plane performance was poor, and surface problems such as wrinkles also occurred.
Further, in the present invention, stable performance can be ensured even if the oxygen concentration and irradiation amount at the time of ultraviolet irradiation are varied.

[Example B-2]
In the preparation methods of Samples 109 and 116 of Example B-1, only samples 119 to 122 (Samples 119 and 120 are different from the preparation method of Sample 109, Sample 121 and 122 was manufactured by the manufacturing method of the sample 116), and the same evaluation was performed. The film surface temperature of the film was adjusted by changing the temperature of the metal plate in contact with the film back surface. The results are shown in Table 14.

  It has been found that the temperature difference between the film surface temperature during UV irradiation and the film surface temperature in the subsequent steps is preferably 20 ° C. or less from the viewpoint of in-plane uniformity and surface shape.

[Example B-3]
In the preparation methods of Samples 108 and 109 of Example B-1, Samples 123 to 128 differing only in passing through a zone substituted with nitrogen before the ultraviolet irradiation zone were prepared, and the same evaluation was performed. The maintenance time is the time during which the film surface temperature of the film is maintained at a desired temperature.

  The results are shown in Table 16. Scratch resistance was improved by passing through a zone having an oxygen concentration of 3% or less.

[Example B-4]
In Examples B-1 to B-3, the fluorine-containing polymer used in the low refractive index layer was changed to copolymers P-1 and P-2 described in JP-A-2004-45462, respectively (equal mass replacement), and the same evaluation was performed. As a result, the same effects as in Examples B-1 to B-3 were obtained.

[Example B-5]
(Preparation of coating solution for hard coat layer)
The following composition was put into a mixing tank and stirred to obtain a hard coat layer coating solution.
────────────────────────────────────────
Coating composition for hard coat layer ────────────────────────────────────────
Desolite Z7404 100 parts by weight (Zirconia fine particle-containing hard coat composition liquid: solid content concentration 60 wt%, zirconia fine particle content 70 wt% vs. solid content, average particle diameter of about 20 nm, solvent composition MIBK: MEK = 9: 1
, Made by JSR Corporation)
DPHA (UV curable resin: manufactured by Nippon Kayaku Co., Ltd.) 31 parts by mass KBM-5103 (silane coupling agent: manufactured by Shin-Etsu Chemical Co., Ltd.)
10 parts by mass KE-P150 (1.5 μm silica particles: manufactured by Nippon Shokubai Co., Ltd.) 8.9 parts by mass MXS-300 (3 μm cross-linked PMMA particles: manufactured by Soken Chemical Co., Ltd.) 3.4 parts by mass MEK 29 parts by mass MIBK 13 parts by mass
────────────────────────────────────────

(Preparation of coating solution for low refractive index layer)
A coating solution for a low refractive index layer was prepared in the same manner as in Example B-1.

(Preparation of antireflection film 501)
A triacetyl cellulose film (TD80U, manufactured by Fuji Photo Film Co., Ltd.) is rolled out as a transparent substrate, and the above hard coat layer coating solution has a gravure pattern of 135 lines / inch and a depth of 60 μm. Using a micro gravure roll with a diameter of 50 mm and a doctor blade, it was applied at a transfer speed of 10 m / min, dried at 60 ° C. for 150 seconds, and further under a nitrogen purge, a 160 W / cm air-cooled metal halide lamp (eye graphics ( using Ltd.)), illuminance 400 mW / cm ^2, thereby curing the coated layer by an irradiation dose of 250 mJ / cm ^2, to form a hard coat layer it was wound. After curing, the gravure roll rotation speed was adjusted so that the thickness of the hard coat layer was 3.6 μm.

The transparent base material coated with the hard coat layer was unwound again, and the coating liquid for the low refractive index layer was coated with a microgravure roll having a diameter of 200 lines / inch and a gravure pattern having a depth of 30 μm and a diameter of 50 mm and a doctor blade. Using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) with an oxygen concentration of 0.1% by volume after applying for 30 seconds at 90 ° C. and applying at a conveyance speed of 10 m / min. It was used to irradiate ultraviolet rays having an illuminance of 600 mW / cm ² and an irradiation amount of 400 mJ / cm ² to form a low refractive index layer and wind it up. After curing, the rotation speed of the gravure roll was adjusted so that the thickness of the low refractive index layer was 100 nm. In the case of heating after ultraviolet irradiation, the film after irradiation was brought into contact with a rotating metal roll through which hot water or pressurized steam was passed.

  Samples 502 to 516 were prepared by changing the curing conditions of the low refractive index layer as shown in Table 17.

These samples were evaluated in the same manner as in Example B-1. The results are shown in Table 18.
It was found that by the curing method of the present invention, excellent scratch resistance was obtained while maintaining antireflection performance.

[Example B-6]
In the preparation methods of Samples 508 and 509 of Example B-5, Samples 517 to 522 that differ only in passing through a nitrogen-substituted zone before the ultraviolet irradiation zone were prepared, and the same evaluation was performed. The maintenance time is the time during which the film surface temperature of the film is maintained at a desired temperature.

  The results are shown in Table 20. Scratch resistance is improved by passing through a zone having an oxygen concentration of 3% or less.

[Example B-7]
The low refractive index layer coating liquids of Examples B-1 to 6 were changed to the following low refractive index layer coating liquids A and B, respectively, and evaluations were made, and similar effects of the present invention could be confirmed.
By using the hollow silica particles, it was possible to produce a low-reflectance antireflection film with further excellent scratch resistance.

(Preparation of sol solution a)
A stirrer, a reactor equipped with a reflux condenser, 120 parts of methyl ethyl ketone, 100 parts of acryloyloxypropyltrimethoxysilane (KBM-5103, manufactured by Shin-Etsu Chemical Co., Ltd.), diisopropoxyaluminum ethyl acetoacetate (trade name: Kerope EP) -12, manufactured by HOPE PHARMACEUTICAL CO., LTD.) After mixing, 30 parts of ion-exchanged water was added and reacted at 60 ° C. for 4 hours, followed by cooling to room temperature to obtain sol solution a. The mass average molecular weight was 1600, and among the components higher than the oligomer component, the component having a molecular weight of 1000 to 20000 was 100%. Further, from the gas chromatography analysis, the raw material acryloyloxypropyltrimethoxysilane did not remain at all.

(Preparation of hollow silica fine particle dispersion)
In 500 parts of hollow silica fine particle sol (isopropyl alcohol silica sol, CS60-IPA manufactured by Catalytic Chemical Industry Co., Ltd., average particle diameter 60 nm, shell thickness 10 nm, silica concentration 20%, silica particle refractive index 1.31), acryloyloxypropyl After adding and mixing 30 parts of trimethoxysilane (Shin-Etsu Chemical Co., Ltd., KBM-5103) and 1.5 parts of diisopropoxyaluminum ethyl acetoacetate (trade name: Kerope EP-12, manufactured by Hope Pharmaceutical Co., Ltd.) 9 parts of ion exchange water were added. After making it react at 60 degreeC for 8 hours, it cooled to room temperature and added 1.8 parts of acetylacetone, and obtained the hollow silica dispersion liquid. The resulting hollow silica dispersion had a solid content concentration of 18% by mass and a refractive index after solvent drying of 1.31.

(Preparation of coating solution A for low refractive index layer)
DPHA 3.3g
Hollow silica fine particle dispersion 40.0g
RMS-033 0.7g
Irgacure 907 0.2g
Sol liquid a 6.2g
Methyl ethyl ketone 290.6g
Cyclohexanone 9.0g

(Preparation of coating solution B for low refractive index layer)
DPHA 1.4g
5.6 g of copolymer P-3 described in JP-A-2004-45462
Hollow silica fine particle dispersion 20.0g
RMS-033 0.7g
Irgacure 907 0.2g
Sol liquid a 6.2g
Methyl ethyl ketone 306.9g
Cyclohexanone 9.0g

The compounds used are shown below.
KBM-5103: Silane coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd.).
DPHA: A mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (manufactured by Nippon Kayaku Co., Ltd.)
RMS-033: Reactive silicone (Gelest)
Irgacure 907: Photopolymerization initiator (Ciba Specialty Chemicals Co., Ltd.)

[Example B-8]
The low refractive index layer coating liquids of Examples B-1 to B-6 were changed to the following low refractive index layer coating liquids C, respectively, and evaluations were made, and similar effects of the present invention could be confirmed. The same effect was obtained with a low refractive index layer in which OPSTA JN7228A was replaced with JTA113 (manufactured by JSR Co., Ltd.) having an increased degree of cross-linking with equal weight.

(Preparation of coating solution C for low refractive index layer)
The following composition was put into a mixing tank, stirred, and then filtered through a polypropylene filter having a pore size of 1 μm to prepare a coating solution C for a low refractive index layer.
────────────────────────────────────────
Coating composition C for low refractive index layer ─────────────────────────────────────────
OPSTAR JN7228A (polysiloxane and hydroxyl group-containing thermally crosslinkable fluorine-containing polymer composition: manufactured by JSR Corporation) 100 parts by mass MEK-ST (silica dispersion, average particle size 15 nm: manufactured by Nissan Chemical Industries, Ltd.)
4.3 parts by mass MEK-ST with different particle size (silica dispersion, average particle size 45 nm: manufactured by Nissan Chemical Co., Ltd.)
5.1 parts by mass Sol solution a (prepared in Example B-7) 2.2 parts by mass MEK 15 parts by mass Cyclohexanone 3.6 parts by mass ──────────────── ────────────────────────

  The low-refractive index layer coating liquid C was applied at a conveyance speed of 10 m / min using a microgravure roll with a diameter of 50 mm and a doctor blade having a gravure pattern of 200 lines / inch and a depth of 30 μm, and 120 ° C. After drying for 150 seconds, ultraviolet irradiation of Examples B-1 to 6 was performed. After curing, the rotation speed of the gravure roll was adjusted so that the thickness of the low refractive index layer was 100 nm.

[Example B-9]
(Preparation of protective film for polarizing plate)
A saponification solution in which a 1.5 mol / L sodium hydroxide aqueous solution was kept at 50 ° C. was prepared.
Furthermore, a 0.005 mol / L dilute sulfuric acid aqueous solution was prepared.
In the antireflection films prepared in Examples B-1 to 8, the surface of the transparent substrate opposite to the side having the high refractive index layer of the present invention was saponified using the saponification solution.
The aqueous sodium hydroxide solution on the surface of the saponified transparent substrate is thoroughly washed with water, then washed with the above diluted sulfuric acid aqueous solution, and further, the diluted sulfuric acid aqueous solution is thoroughly washed with water and sufficiently dried at 100 ° C. It was.
When the contact angle of the surface of the saponified transparent substrate on the side opposite to the side having the high refractive index layer of the antireflection film was evaluated, it was 40 degrees or less. Thus, the protective film for polarizing plates was produced.

[Example B-10]
(Preparation of polarizing plate)
A polyvinyl alcohol film having a thickness of 75 μm (manufactured by Kuraray Co., Ltd.) was immersed in an aqueous solution consisting of 1000 parts by mass of water, 7 parts by mass of iodine, and 105 parts by mass of potassium iodide to adsorb iodine.
Subsequently, this film was uniaxially stretched 4.4 times in the longitudinal direction in a 4% by mass boric acid aqueous solution, and then dried in a tension state to produce a polarizing film.
A saponified triacetyl cellulose surface of the antireflection film of the present invention (protective film for polarizing plate) was bonded to one surface of the polarizing film using a polyvinyl alcohol-based adhesive as an adhesive. Further, a triacetyl cellulose film saponified in the same manner as described above was bonded to the other surface of the polarizing film using the same polyvinyl alcohol-based adhesive.

(Evaluation of image display device)
The TN, STN, IPS, VA, OCB mode transmission type, reflection type, or transflective type in which the polarizing plate of the present invention thus prepared is mounted so that the antireflection film is the outermost surface of the display. The liquid crystal display device was excellent in antireflection performance and extremely excellent in visibility. In particular, the effect is remarkable in the VA mode.

[Example B-11]
(Preparation of polarizing plate)
In the optical compensation film having an optical compensation layer (Wide View Film SA 12B, manufactured by Fuji Photo Film Co., Ltd.), the surface opposite to the side having the optical compensation layer is saponified under the same conditions as in Example B-9. did.
An antireflection film (protective film for polarizing plate) saponified in Example B-9 on one surface of the polarizing film using a polyvinyl alcohol-based adhesive as an adhesive for the polarizing film prepared in Example B-10 The saponified triacetyl cellulose surfaces were bonded to each other. Further, the triacetyl cellulose surface of the saponified optical compensation film was bonded to the other surface of the polarizing film using the same polyvinyl alcohol adhesive.

(Evaluation of image display device)
The TN, STN, IPS, VA, OCB mode transmission type, reflection type, or transflective type in which the polarizing plate of the present invention thus prepared is mounted so that the antireflection film is the outermost surface of the display. The liquid crystal display device has better contrast in the bright room than the liquid crystal display device equipped with a polarizing plate that does not use an optical compensation film, has a very wide viewing angle in the vertical and horizontal directions, and has excellent antireflection performance and extremely high visibility. The display and display quality were excellent.
In particular, the effect is remarkable in the VA mode.

[Example B-12]
In the production method of the antireflection film 109 of Example B-1, the coating solution formulation of the low refractive index layer was changed to LL-61 below, and coating was performed at a coating speed of 25 m / min using the following die coater.
Then, after drying at 90 ° C. for 30 seconds, using a 240 W / cm air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) while purging with nitrogen so that the atmosphere has an oxygen concentration of 0.1% by volume or less, An ultraviolet ray having an illuminance of 600 mW / cm ² and an irradiation amount of 400 mJ / cm ² was irradiated to form a low refractive index layer (refractive index 1.45, film thickness 83 nm). In this way, an antireflection film (11-1) was produced.
Furthermore, antireflection films (11-2) to (11-5) were produced by changing the low refractive index layer coating solution to LL-62 to 65.

(Die coater configuration)
The slot die 13 has an upstream lip land length I _UP of 0.5 mm, a downstream lip land length I _LO of 50 μm, a length of the opening of the slot 16 in the web running direction of 150 μm, and a length of the slot 16 of 50 mm. I used one. The gap between the upstream lip land 18a and the web is made 50 μm longer than the gap between the downstream lip land 18b and the web (hereinafter referred to as an overbite length of 50 μm), and the gap _GL between the downstream lip land 18b and the web is The thickness was set to 50 μm. Further, the gap G _S between the side plate 40b and the web of the decompression chamber 40, and the gap G _B between the back plate 40a and the web were both 200 [mu] m.

(Preparation of coating solution for low refractive index layer (LL-61))
152.4 parts by mass of a solution obtained by dissolving the copolymer P-3 described in JP-A-2004-45462 in methyl ethyl ketone so as to have a concentration of 23.7% by mass, a terminal methacrylate group-containing silicone resin X-22-164C ( (Shin-Etsu Chemical Co., Ltd.) 1.1 parts by mass, photo radical generator Irgacure 907 (Ciba Specialty Chemicals Co., Ltd.) 1.8 parts by mass, methyl ethyl ketone 815.9 parts by mass, and cyclohexanone 28.8 parts by mass Was added and stirred. The mixture was filtered through a PTFE filter having a pore diameter of 0.45 μm to prepare a coating solution for low refractive index layer (LL-61). The viscosity of the coating solution was 0.61 [mPa · sec], the surface tension was 24 [mN / m], and the amount of the coating solution applied to the transparent substrate was 2.8 [ml / m ² ]. .

(Preparation of coating solution for low refractive index layer (LL-62))
426.6 parts by mass of a solution obtained by dissolving the above copolymer P-3 in methyl ethyl ketone so as to have a concentration of 23.7% by mass, terminal methacrylate group-containing silicone resin X-22-164C (manufactured by Shin-Etsu Chemical Co., Ltd.) 3.0 parts by mass, 5.1 parts by mass of photo radical generator Irgacure 907 (manufactured by Ciba Specialty Chemicals), 538.6 parts by mass of methyl ethyl ketone, and 26.7 parts by mass of cyclohexanone were added and stirred. The mixture was filtered through a PTFE filter having a pore diameter of 0.45 μm to prepare a coating solution for low refractive index layer (LL-62). The viscosity of the coating solution was 1.0 [mPa · sec], the surface tension was 24 [mN / m], and the amount of the coating solution applied to the transparent substrate was 1.5 [ml / m ² ]. .

(Preparation of coating solution for low refractive index layer (LL-63))
213.3 parts by mass of a solution obtained by dissolving the above copolymer P-3 in methyl ethyl ketone to a concentration of 23.7% by mass, terminal methacrylate group-containing silicone resin X-22-164C (manufactured by Shin-Etsu Chemical Co., Ltd.) 1.5 parts by mass, 2.5 parts by mass of photoradical generator Irgacure 907 (manufactured by Ciba Specialty Chemicals Co., Ltd.), 754.3 parts by mass of methyl ethyl ketone, and 28.4 parts by mass of cyclohexanone were added and stirred. The mixture was filtered through a PTFE filter having a pore diameter of 0.45 μm to prepare a coating solution for low refractive index layer (LL-63). The viscosity of the coating solution was 0.76 [mPa · sec], the surface tension was 24 [mN / m], and the amount of the coating solution applied to the transparent substrate was 2.0 [ml / m ² ]. .

(Preparation of coating solution for low refractive index layer (LL-64))
85.3 parts by mass of a solution obtained by dissolving the above copolymer P-3 in methyl ethyl ketone so as to have a concentration of 23.7% by mass, terminal methacrylate group-containing silicone resin X-22-164C (manufactured by Shin-Etsu Chemical Co., Ltd.) 0.6 parts by mass, 1.0 part by mass of photoradical generator Irgacure 907 (manufactured by Ciba Specialty Chemicals Co., Ltd.), 883.7 parts by mass of methyl ethyl ketone, and 29.3 parts by mass of cyclohexanone were added and stirred. The mixture was filtered through a PTFE filter having a pore diameter of 0.45 μm to prepare a coating solution for low refractive index layer (LL-64). The viscosity of the coating solution was 0.49 [mPa · sec], the surface tension was 24 [mN / m], and the amount of the coating solution applied to the transparent substrate was 5.0 [ml / m ² ]. .

(Preparation of coating solution for low refractive index layer (LL-65))
71.1 parts by mass of a solution obtained by dissolving the above copolymer P-3 in methyl ethyl ketone so as to have a concentration of 23.7% by mass, a terminal methacrylate group-containing silicone resin X-22-164C (manufactured by Shin-Etsu Chemical Co., Ltd.) 0.5 parts by mass, 0.8 parts by mass of photoradical generator Irgacure 907 (manufactured by Ciba Specialty Chemicals Co., Ltd.), 898.1 parts by mass of methyl ethyl ketone, and 29.5 parts by mass of cyclohexanone were added and stirred. The mixture was filtered through a PTFE filter having a pore diameter of 0.45 μm to prepare a coating solution for low refractive index layer (LL-65). The viscosity of the coating solution was 0.46 [mPa · sec], the surface tension was 24 [mN / m], and the amount of the coating solution applied to the transparent substrate was 6.0 [ml / m ² ]. .

The surface shapes of the antireflection films (11-1) to (11-5) prepared by changing the coating solution for the low refractive index layer to LL-61 to LL-65 were evaluated. The results are shown in Table 21. When the amount of the coating solution applied to the transparent substrate is 2 ml / m ² or more, the coating solution can be applied. However, when the amount is 1.5 ml / m ² , the entire surface cannot be applied uniformly, and an antireflection film is created. I couldn't. In addition, when the amount of the coating solution applied to the transparent substrate is 6 ml / m ² , the coating is possible, but since the amount of the coating solution is large, drying is not in time, and vertical streaky unevenness caused by the wind. Occurred on the entire surface.
When the display apparatus was produced for the obtained antireflection film (11-1), (11-3), (11-4) in the same procedure as Example B-11, Example B- produced with a gravure coater was used. There was less color unevenness than the 11 display devices, and the quality was high.

[Example B-13]
Antireflection films (12-1) to (12-4) were produced in the same manner as the antireflection film (11-1) except that the downstream lip land length I _L0 was 10 μm, 30 μm, 100 μm, and 120 μm. The results are shown in Table 22. When the length of the downstream lip land is in the range of 30 μm to 100 μm, an antireflection film free from surface failure can be obtained. In the antireflection film (12-1), streaky unevenness occurs in the longitudinal direction of the base, and the antireflection film (12-4) cannot form the beads 14a at the same speed as the antireflection film (11-1). Application was impossible. Application was possible by reducing the application speed to half, but streaky irregularities occurred in the longitudinal direction of the base. When the antireflection films (12-2) and (12-3) were produced by the same procedure as in Example B-11, the background reflection was very small, and the color of the reflected light was significantly reduced. Furthermore, a display device with very high display quality in which uniformity within the display surface was ensured was obtained. On the other hand, when an antireflection film obtained from the antireflection films (12-1) and (12-4) is produced in the same procedure as in Example B-11, uneven coloring is visually recognized in the display device. I couldn't say it was high quality.

[Example B-14]
Coating was performed in the same manner as (11-1) except that the overcoat length LO of the die coater was 0 μm, 30 μm, 120 μm, and 150 μm, and antireflection films (13-1) to (13-4) were produced. . The results are shown in Table 23. When the overbite length is in the range of 30 μm to 120 μm, an antireflection film free from surface defects can be obtained. Application was possible with the antireflection film (13-1), but stepped unevenness was recognized in the base width direction when the surface shape was seen. Further, in the antireflection film (13-4), the beads 14a could not be formed at the same speed as (13-1), and the coating was impossible. Application was possible by reducing the application speed to half, but streaky irregularities occurred in the longitudinal direction of the base. In the antireflection films (13-2) and (13-3), when a display device was prepared in the same procedure as in Example B-11, the reflection of the background was extremely small, and the color of the reflected light was significantly reduced. Furthermore, a display device with very high display quality in which uniformity within the display surface was ensured was obtained. On the other hand, when a display device is created with the antireflection films (13-1) and (13-4) in the same procedure as in Example B-11, uneven coloring is visually recognized in the display device, which cannot be said to be high quality. It was.

(Embodiment of layer forming method (III))
[Example C-1]
(Preparation of coating solution for hard coat layer)
The following composition was put into a mixing tank and stirred to obtain a hard coat layer coating solution.
750.0 parts by weight of trimethylolpropane triacrylate (Biscoat # 295 (manufactured by Osaka Organic Chemical Co., Ltd.)), 270.0 parts by mass of polyglycidyl methacrylate having a mass average molecular weight of 15000, 730.0 parts by mass of methyl ethyl ketone, 500.0 cyclohexanone Mass parts and 50.0 parts by mass of a photopolymerization initiator (Irgacure 184, manufactured by Ciba Specialty Chemicals Co., Ltd.) were added and stirred, and filtered through a polypropylene filter having a pore size of 0.4 μm for the hard coat layer. A polyglycidyl methacrylate was prepared by dissolving glycidyl methacrylate (manufactured by Daicel Chemical Industries, Ltd.) in methyl ethyl ketone (MEK) and adding a thermal polymerization initiator (V-65 (manufactured by Wako Pure Chemical Industries, Ltd.)). Reaction solution obtained by reacting at 80 ° C. for 2 hours while dropping. It was added dropwise to hexane, and the precipitate obtained was dried under reduced pressure.

(Preparation of titanium dioxide fine particle dispersion)
As the titanium dioxide fine particles, titanium dioxide fine particles (MPT-129C, manufactured by Ishihara Sangyo Co., Ltd., TiO ₂ : Co ₃ O ₄ : containing cobalt and surface-treated with aluminum hydroxide and zirconium hydroxide: Al ₂ O ₃ : ZrO ₂ = 90.5: 3.0: 4.0: 0.5 weight ratio) was used.
The following dispersant (41.1 parts by mass) and cyclohexanone (701.8 parts by mass) were added to 257.1 parts by mass of the particles and dispersed by dynomill to prepare a titanium dioxide dispersion having a weight average diameter of 70 nm.
Dispersant

(Preparation of coating solution for medium refractive index layer)
In 99.1 parts by mass of the above titanium dioxide dispersion, 68.0 parts by mass of a mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (DPHA, manufactured by Nippon Kayaku Co., Ltd.), a photopolymerization initiator (Irgacure 907) 3.6 parts by mass, manufactured by Ciba Specialty Chemicals Co., Ltd., 1.2 parts by mass of photosensitizer (Kayacure DETX, manufactured by Nippon Kayaku Co., Ltd.), 279.6 parts by mass of methyl ethyl ketone, and 1049.0 of cyclohexanone. A part by mass was added and stirred. After sufficiently stirring, the solution was filtered through a polypropylene filter having a pore diameter of 0.4 μm to prepare a coating solution for a medium refractive index layer.

(Preparation of coating solution for high refractive index layer)
To 469.8 parts by mass of the above titanium dioxide dispersion, 40.0 parts by mass of a mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (DPHA, Nippon Kayaku Co., Ltd.), a photopolymerization initiator (Irgacure 907) 3.3 parts by mass, manufactured by Ciba Specialty Chemicals Co., Ltd., 1.1 parts by mass of photosensitizer (Kayacure-DETX, manufactured by Nippon Kayaku Co., Ltd.), 526.2 parts by mass of methyl ethyl ketone, and cyclohexanone 459 .6 parts by mass was added and stirred. The solution was filtered through a polypropylene filter having a pore diameter of 0.4 μm to prepare a coating solution for a high refractive index layer.

(Preparation of coating solution for low refractive index layer)
A copolymer P-3 described in JP-A-2004-45462 is dissolved in methyl isobutyl ketone so as to have a concentration of 7% by mass, and a terminal methacrylate group-containing silicone resin X-22-164C (Shin-Etsu Chemical Co., Ltd.) 3% of the solid content and 5% by mass of the photoradical generator Irgacure 907 (trade name) based on the solid content to prepare a coating solution for a low refractive index layer.

(Preparation of antireflection film 101)
A hard coat layer coating solution was applied onto a triacetyl cellulose film (TD-80UF, manufactured by Fuji Photo Film Co., Ltd.) having a thickness of 80 μm using a gravure coater. After drying at 100 ° C., an irradiance of 400 mW / cm using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) of 160 W / cm while purging with nitrogen so that the oxygen concentration becomes 1.0 vol% or less. ^{2. The} coating layer was cured by irradiating ultraviolet rays with an irradiation amount of 300 mJ / cm ² to form a hard coat layer having a thickness of 8 μm.
On the hard coat layer, a medium refractive index layer coating solution, a high refractive index layer coating solution, and a low refractive index layer coating solution are continuously applied at a speed of 30 m / min using a gravure coater having three coating stations. And applied.

The medium refractive index layer was dried at 90 ° C. for 30 seconds, and the ultraviolet curing condition was 180 W / cm air-cooled metal halide lamp (eye graphics) while purging with nitrogen so that the atmosphere had an oxygen concentration of 1.0% by volume or less. ), And the irradiation dose was 400 mW / cm ² and the irradiation dose was 400 mJ / cm ² .
The medium refractive index layer after curing had a refractive index of 1.630 and a film thickness of 67 nm.

The drying condition of the high refractive index layer is 90 ° C. for 30 seconds, and the ultraviolet curing condition is a 240 W / cm air-cooled metal halide lamp (eye graphics) while purging with nitrogen so that the atmosphere has an oxygen concentration of 1.0% by volume or less. ), And the irradiation dose was 600 mW / cm ² and the irradiation dose was 400 mJ / cm ² .
The cured high refractive index layer had a refractive index of 1.905 and a film thickness of 107 nm.

Drying conditions of the low refractive index layer 90 ° C., and 30 seconds, 1.40 m in the reaction chamber of the nitrogen purge (0.2 m ³ as the ultraviolet curing conditions the oxygen concentration falls below the ambient 0.1% by volume ³ / Using a 240 W / cm air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.), the irradiation amount was 600 mW / cm ² and the irradiation amount was 600 mJ / cm ² .
The low refractive index layer after curing had a refractive index of 1.440 and a film thickness of 85 nm. Thus, the antireflection film 101 was produced.
Only the curing conditions of the low refractive index layer were changed to the conditions shown in Table 24, and Samples 102 to 116 were produced. A continuous front chamber was provided immediately before the UV irradiation reaction chamber, and nitrogen gas was blown there. The nozzle position was set so that the blown nitrogen gas directly hit the film surface. The exhaust of the reaction chamber and the front chamber was adjusted so that nitrogen gas was blown out from the web entrance of the front chamber. The gap between the web entrance and the surface of the coating layer on the web was 4 mm.
The ultraviolet irradiation amount when the coating speed was changed was set so that the irradiation amount became constant by changing the illuminance.

The following items were evaluated for the obtained film. The results are shown in Table 25.
[Specular reflectance]
An adapter ARV-474 is attached to a spectroscopic hardness meter V-550 (manufactured by JASCO Corporation), and the specular reflectance at an incident angle of -5 degrees is measured at an incident angle of 5 degrees in a wavelength range of 380 to 780 nm. The average reflectance at 650 nm was calculated and the antireflection property was evaluated.
[Pencil hardness]
The pencil hardness evaluation described in JIS K 5400 was performed. After conditioning the antireflection film at a temperature of 25 ° C. and a humidity of 60% RH for 2 hours, it was evaluated using the H-5H test pencil specified in JIS S 6006 at a load of 500 g as follows. The highest hardness that results in OK was taken as the evaluation value.
In evaluation of n = 5, there is no scratch to one scratch: OK
In evaluation of n = 5, 3 or more scratches: NG

[Steel wool scuff resistance]
The state of scratches was observed when a load of 1.96 N / cm ² was applied to steel steel of # 0000 and reciprocated 30 times, and the following five stages were evaluated.
◎: Scratch not found ○: Slightly invisible scratch △: Clearly visible scratch ×: Clearly visible scratch XX: Delamination of the film occurred thing

  According to the curing conditions of the present invention, it was found that the antireflection film of the present invention was excellent in scratch resistance while having sufficient antireflection performance. Further, it was found that by blowing nitrogen, the scratch resistance was excellent even when the oxygen concentration in the reaction chamber was the same.

[Example C-2]
In the preparation methods of Samples 103 and 115 of Example C-1, sample samples 117 to 119 that are different only in that the film surface temperature at the time of ultraviolet irradiation was raised (the same production method as Sample 103 except that the temperature was raised), 120 to 122 (same production method as the sample 115 except that the temperature was raised) was produced, and the same evaluation was performed.
The temperature of the film surface was adjusted by changing the temperature of the metal plate in contact with the film back surface.

  In the present invention, further superior scratch resistance was obtained by raising the temperature during UV irradiation to 60 ° C. or higher.

[Example C-3]
Samples 123 to 126 in Table 27 were prepared by changing the number of divisions of ultraviolet irradiation and the presence or absence of nitrogen substitution between ultraviolet irradiations in the method for manufacturing the sample 103 prepared in Example C-1.
Evaluation similar to Example C-1 was performed with respect to these samples.
In the ultraviolet irradiation division, the illuminance was adjusted so that the total irradiation amount was constant. The results are shown in Table 28.
It was found that, even when the ultraviolet irradiation was divided and the illuminance at one time was reduced, the oxygen concentration was reduced to 3% by volume or less so that the abrasion resistance was not deteriorated and high-speed production suitability was obtained.

[Example C-4]
In the preparation method of the sample 103 of Example C-1, the gap between the front chamber entrance and the web surface and the flow of nitrogen gas on the entrance side are changed, and the oxygen concentration in the ultraviolet irradiation reaction chamber becomes constant at 0.08%. Thus, the amount of purge nitrogen gas was adjusted to prepare Samples 127 to 130, and the same evaluation as in Example C-1 was performed.
It was found that a low oxygen concentration can be maintained with a small amount of nitrogen gas by narrowing the gap and adjusting the exhaust gas so that the nitrogen gas at the inlet side of the web is slightly blown out.

[Example C-5]
The fluorine-containing copolymer P-3 used in the coating solution for the low refractive index layer in Examples C-1 to 4 was changed to P-1 and P-2 of the copolymer described in JP-A-2004-45462. As a result of carrying out the same preparation and evaluation by changing each (replacement with equal mass), the same effects as in Examples C-1 to C-4 were obtained.

[Example C-6]
(Preparation of coating solution for hard coat layer)
The following composition was put into a mixing tank and stirred to obtain a hard coat layer coating solution.
───────────────────────────────────────
Coating solution composition for hard coat layer ───────────────────────────────────────
Desolite Z7404 (Hardcoat composition liquid containing zirconia fine particles: solid content concentration 60 wt%, zirconia fine particle content 70 wt% vs. solid content, average particle diameter of about 20 nm, solvent composition MIBK: MEK = 9: 1, JSR Corporation 100 parts by mass DPHA (UV curable resin: manufactured by Nippon Kayaku Co., Ltd.) 31 parts by mass KBM-5103 (silane coupling agent: manufactured by Shin-Etsu Chemical Co., Ltd.)
10 parts by mass KE-P150 (1.5 μm silica particles: manufactured by Nippon Shokubai Co., Ltd.)
8.9 parts by mass MXS-300 (3 μm crosslinked PMMA particles: manufactured by Soken Chemical Co., Ltd.)
3.4 parts by weight MEK (methyl ethyl ketone) 29 parts by weight MIBK (methyl isobutyl ketone) 13 parts by weight ──────────────────────────── ─────────

(Preparation of coating solution for low refractive index layer)
A coating solution for a low refractive index layer was prepared in the same manner as in Example C-1.

(Preparation of antireflection film 501)
As a transparent substrate, a triacetyl cellulose film (TD80U, manufactured by Fuji Photo Film Co., Ltd.) is unwound in a roll form, and the above coating liquid for hard coat layer has a gravure pattern of 135 lines / inch and a depth of 60 μm. Using a micro gravure roll with a diameter of 50 mm and a doctor blade, the coating was carried out at a conveyance speed of 10 m / min, dried at 60 ° C. for 150 seconds, and further under a nitrogen purge, a 160 W / cm air-cooled metal halide lamp (eye graphics ( Co., Ltd.) was used to cure the coating layer by irradiating ultraviolet rays with an illuminance of 400 mW / cm ² and an irradiation amount of 250 mJ / cm ² to form a hard coat layer 1 and wound it. After curing, the gravure roll rotation speed was adjusted so that the thickness of the hard coat layer was 3.6 μm.

The transparent base material coated with the hard coat layer was unwound again, and the coating liquid for the low refractive index layer was coated with a microgravure roll having a diameter of 200 lines / inch and a gravure pattern having a depth of 30 μm and a diameter of 50 mm and a doctor blade. Using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) with an oxygen concentration of 0.1% by volume after applying for 30 seconds at 90 ° C. and applying at a conveyance speed of 10 m / min. It was used to irradiate ultraviolet rays having an illuminance of 600 mW / cm ² and an irradiation amount of 400 mJ / cm ² to form a low refractive index layer and wind it up. After curing, the rotation speed of the gravure roll was adjusted so that the thickness of the low refractive index layer was 100 nm.

  Samples 502 to 516 were prepared by changing the curing conditions of the low refractive index layer as shown in Table 30.

These samples were evaluated in the same manner as in Example C-1. The results are shown in Table 31.
It was found that by the curing method of the present invention, excellent scratch resistance was obtained while maintaining antireflection performance.

[Example C-7]
The low refractive index layer coating liquids of Examples C-1 to C-6 were prepared and evaluated by changing to the following low refractive index layer coating liquids A and B, respectively, and similar effects of the present invention could be confirmed.
By using the hollow silica particles, it was possible to produce an antireflection film having further excellent abrasion resistance and a lower reflectance.

(Preparation of sol solution a)
A reactor equipped with a stirrer and a reflux condenser, 120 parts of methyl ethyl ketone, 100 parts of acryloyloxypropyltrimethoxysilane (KBM-5103, manufactured by Shin-Etsu Chemical Co., Ltd.), diisopropoxyaluminum ethyl acetoacetate ("Kelope EP-12") “Hope Pharmaceutical Co., Ltd.) 3 parts was added and mixed, and then 30 parts of ion-exchanged water was added and reacted at 60 ° C. for 4 hours, and then cooled to room temperature to obtain sol solution a. The mass average molecular weight was 1600, and among the components higher than the oligomer component, the component having a molecular weight of 1000 to 20000 was 100%. Further, from the gas chromatography analysis, the raw material acryloyloxypropyltrimethoxysilane did not remain at all.

(Preparation of hollow silica fine particle dispersion)
Hollow silica fine particle sol (particle size about 40-50 nm, shell thickness 6-8 nm, refractive index 1.31, solid content concentration 20%, main solvent isopropyl alcohol, particle size according to Preparation Example 4 of JP-A-2002-79616 500 parts, 30 parts acryloyloxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., KBM-5103), and diisopropoxyaluminum ethyl acetoacetate ("Kerope EP-12" Hope Pharmaceutical Co., Ltd.) (Product made) After 1.5 parts were added and mixed, 9 parts of ion-exchanged water was added. After making it react at 60 degreeC for 8 hours, it cooled to room temperature and added 1.8 parts of acetylacetone, and obtained the hollow silica dispersion liquid. The resulting hollow silica dispersion had a solid content concentration of 18% by mass and a refractive index after solvent drying of 1.31.

(Preparation of coating solution A for low refractive index layer)
DPHA 3.3g
Hollow silica fine particle dispersion 40.0g
RMS-033 0.7g
Irgacure 907 0.2g
Sol liquid a 6.2g
Methyl ethyl ketone 290.6g
Cyclohexanone 9.0g

(Preparation of coating solution B for low refractive index layer)
DPHA 1.4g
Copolymer P-3 (described in JP 2004-45462 A) 5.6 g
Hollow silica fine particle dispersion 20.0g
RMS-033 0.7g
Irgacure 907 0.2g
Sol liquid a 6.2g
Methyl ethyl ketone 306.9g
Cyclohexanone 9.0g

The compounds used are shown below.
KBM-5103: Silane coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd.).
DPHA: A mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (manufactured by Nippon Kayaku Co., Ltd.)
RMS-033: Reactive silicone (manufactured by Gelest Co., Ltd.)
Irgacure 907: Photopolymerization initiator (Ciba Specialty Chemicals Co., Ltd.)

[Example C-8]
When the coating liquid for low refractive index layer of Examples C-1 to 7 was changed to the following coating liquid C for low refractive index layer and was prepared and evaluated, the same effects of the present invention were confirmed. The same effect was obtained even when the coating solution for low refractive index layer in which OPSTA JN7228A was replaced with JTA113 (manufactured by JSR Co., Ltd.) having a higher degree of cross-linking with equal weight was used.

(Preparation of sol solution a)
A reactor equipped with a stirrer and a reflux condenser, 120 parts of methyl ethyl ketone, 100 parts of acryloyloxypropyltrimethoxysilane (KBM-5103 (trade name); manufactured by Shin-Etsu Chemical Co., Ltd.), diisopropoxyaluminum ethyl acetoacetate ("Kelope EP") After adding 3 parts of “-12” manufactured by Hope Pharmaceutical Co., Ltd. and mixing, 30 parts of ion-exchanged water was added and reacted at 60 ° C. for 4 hours, followed by cooling to room temperature to obtain sol solution a. The mass average molecular weight was 1800, and among the components higher than the oligomer component, the component having a molecular weight of 1000 to 20000 was 100%. Further, from the gas chromatography analysis, the raw material acryloyloxypropyltrimethoxysilane did not remain at all.

(Preparation of coating solution C for low refractive index layer)
The following composition was put into a mixing tank, stirred, and then filtered through a polypropylene filter having a pore size of 1 μm to prepare a coating solution C for a low refractive index layer.
────────────────────────────────────
Composition C for low refractive index layer ────────────────────────────────────
OPSTAR JN7228A (polysiloxane and hydroxyl group-containing thermally crosslinkable fluorine-containing polymer composition: manufactured by JSR Corporation) 100 parts by mass MEK-ST (silica dispersion, average particle size 15 nm: manufactured by Nissan Chemical Industries, Ltd.)
4.3 parts by mass MEK-ST with different particle size (silica dispersion, average particle size 45 nm: manufactured by Nissan Chemical Co., Ltd.)
5.1 parts by mass Sol solution a 2.2 parts by mass MEK 15 parts by mass cyclohexanone 3.6 parts by mass ─────────────────────────── ─────────

The coating liquid for the low refractive index layer was applied under the condition of a conveyance speed of 10 m / min using a micro gravure roll having a diameter of 200 lines / inch and a gravure pattern having a depth of 30 μm and a doctor blade at a conveyance speed of 10 m / min. After drying for 150 seconds, after further drying at 140 ° C. for 12 minutes, using a 240 W / cm air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) under a nitrogen purge, an illuminance of 400 mW / cm ² and an irradiation amount The ultraviolet irradiation of Examples C-1 to 7 was performed at 900 mJ / cm ² . After curing, the rotation speed of the gravure roll was adjusted so that the thickness of the low refractive index layer was 100 nm.

[Example C-9]
(Preparation of protective film for polarizing plate)
A saponification solution in which a 1.5 mol / L sodium hydroxide aqueous solution was kept at 50 ° C. was prepared.
Furthermore, a 0.005 mol / L dilute sulfuric acid aqueous solution was prepared.
In the antireflection films prepared in Examples C-1 to C-8, the surface of the transparent substrate opposite to the side having the low refractive index layer of the present invention was saponified using the saponification solution.
The aqueous sodium hydroxide solution on the surface of the saponified transparent substrate is thoroughly washed with water, then washed with the above diluted sulfuric acid aqueous solution, and further, the diluted sulfuric acid aqueous solution is thoroughly washed with water and sufficiently dried at 100 ° C. It was.
When the contact angle of the surface of the saponified transparent substrate on the side opposite to the side having the low refractive index layer of the antireflection film was evaluated, it was 40 degrees or less. Thus, the protective film for polarizing plates was produced.

(Preparation of polarizing plate)
A polyvinyl alcohol film having a thickness of 75 μm (manufactured by Kuraray Co., Ltd.) was immersed in an aqueous solution consisting of 1000 parts by mass of water, 7 parts by mass of iodine, and 105 parts by mass of potassium iodide to adsorb iodine.
Subsequently, this film was uniaxially stretched 4.4 times in the longitudinal direction in a 4% by mass boric acid aqueous solution, and then dried in a tension state to produce a polarizing film.
Triacetyl cellulose obtained by saponifying the antireflection film (protective film for polarizing plate) of the present invention produced in Examples C-1 to 8 on one surface of a polarizing film using a polyvinyl alcohol-based adhesive as an adhesive. The surfaces were pasted together. Further, a triacetyl cellulose film saponified in the same manner as described above was bonded to the other surface of the polarizing film using the same polyvinyl alcohol-based adhesive.

(Evaluation of image display device)
The TN, STN, IPS, VA, OCB mode transmission type, reflection type, or transflective type in which the polarizing plate of the present invention thus prepared is mounted so that the antireflection film is the outermost surface of the display. The liquid crystal display device was excellent in antireflection performance and extremely excellent in visibility. In particular, the effect is remarkable in the VA mode.

[Example C-10]
(Preparation of polarizing plate)
In an optical compensation film having an optical compensation layer (Wide View Film SA 12B, manufactured by Fuji Photo Film Co., Ltd.), the surface opposite to the side having the optical compensation layer is saponified under the same conditions as in Example C-9. did.
Using the polyvinyl alcohol adhesive as an adhesive for the polarizing film prepared in Example C-9, the antireflection film (protecting plate for polarizing plate) prepared in Examples C-1 to 8 on one surface of the polarizing film. The saponified triacetyl cellulose surfaces of the film) were bonded together. Further, the triacetyl cellulose surface of the saponified optical compensation film was bonded to the other surface of the polarizing film using the same polyvinyl alcohol adhesive.

(Evaluation of image display device)
The TN, STN, IPS, VA, OCB mode transmission type, reflection type, or transflective type in which the polarizing plate of the present invention thus prepared is mounted so that the antireflection film is the outermost surface of the display. The liquid crystal display device has better contrast in the bright room than the liquid crystal display device equipped with a polarizing plate that does not use an optical compensation film, has a very wide viewing angle in the vertical and horizontal directions, and has excellent antireflection performance and extremely high visibility. The display and display quality were excellent.
In particular, the effect is remarkable in the VA mode.

[Example C-11]
In the production method of the antireflection film 103 produced in Example C-1, the coating solution formulation for the low refractive index layer was changed to LL-61 below, and coating was performed at a coating speed of 25 m / min using the following die coater. Thereafter, the film was dried at 90 ° C. for 30 seconds, and then irradiated with ultraviolet rays under the same conditions as the antireflection film 103 to form a low refractive index layer (refractive index 1.45, film thickness 83 nm). In this way, an antireflection film (11-1) was produced. Furthermore, antireflection films (11-2) to (11-5) were produced by changing the low refractive index layer coating solution to LL-62 to 65.

(Die coater configuration)
The slot die 13 has an upstream lip land length I _UP of 0.5 mm, a downstream lip land length I _LO of 50 μm, a length of the opening of the slot 16 in the web running direction of 150 μm, and a length of the slot 16 of 50 mm. I used one. The gap between the upstream lip land 18a and the web is made 50 μm longer than the gap between the downstream lip land 18b and the web (hereinafter referred to as an overbite length of 50 μm), and the gap _GL between the downstream lip land 18b and the web is The thickness was set to 50 μm. Further, the gap G _B between the gap G _S, and the back plate 40a and the web between the side plate 40b and the web of the decompression chamber 40 were both 200 [mu] m.

(Preparation of coating solution for low refractive index layer (LL-61))
152.4 parts by mass of a solution obtained by dissolving the copolymer P-3 described in JP-A-2004-45462 in methyl ethyl ketone so as to have a concentration of 23.7% by mass, a terminal methacrylate group-containing silicone resin X-22-164C ( (Shin-Etsu Chemical Co., Ltd.) 1.1 parts by mass, photo radical generator Irgacure 907 (Ciba Specialty Chemicals Co., Ltd.) 1.8 parts by mass, methyl ethyl ketone 815.9 parts by mass, and cyclohexanone 28.8 parts by mass Was added and stirred. The mixture was filtered through a PTFE filter having a pore diameter of 0.45 μm to prepare a coating solution for low refractive index layer (LL-61). The viscosity of the coating solution was 0.61 [mPa · sec], the surface tension was 24 [mN / m], and the amount of the coating solution applied to the transparent substrate was 2.8 [ml / m ² ]. .

(Preparation of coating solution for low refractive index layer (LL-62))
426.6 parts by mass of a solution obtained by dissolving the above copolymer P-3 in methyl ethyl ketone so as to have a concentration of 23.7% by mass, terminal methacrylate group-containing silicone resin X-22-164C (manufactured by Shin-Etsu Chemical Co., Ltd.) 3.0 parts by mass, 5.1 parts by mass of photo radical generator Irgacure 907 (manufactured by Ciba Specialty Chemicals), 538.6 parts by mass of methyl ethyl ketone, and 26.7 parts by mass of cyclohexanone were added and stirred. The mixture was filtered through a PTFE filter having a pore diameter of 0.45 μm to prepare a coating solution for low refractive index layer (LL-62). The viscosity of the coating solution was 1.0 [mPa · sec], the surface tension was 24 [mN / m], and the amount of the coating solution applied to the transparent substrate was 1.5 [ml / m ² ]. .

(Preparation of coating solution for low refractive index layer (LL-63))
213.3 parts by mass of a solution obtained by dissolving the above copolymer P-3 in methyl ethyl ketone to a concentration of 23.7% by mass, terminal methacrylate group-containing silicone resin X-22-164C (manufactured by Shin-Etsu Chemical Co., Ltd.) 1.5 parts by mass, 2.5 parts by mass of photoradical generator Irgacure 907 (manufactured by Ciba Specialty Chemicals Co., Ltd.), 754.3 parts by mass of methyl ethyl ketone, and 28.4 parts by mass of cyclohexanone were added and stirred. The mixture was filtered through a PTFE filter having a pore diameter of 0.45 μm to prepare a coating solution for low refractive index layer (LL-63). The viscosity of the coating solution was 0.76 [mPa · sec], the surface tension was 24 [mN / m], and the amount of the coating solution applied to the transparent substrate was 2.0 [ml / m ² ]. .

(Preparation of coating solution for low refractive index layer (LL-64))
85.3 parts by mass of a solution obtained by dissolving the above copolymer P-3 in methyl ethyl ketone so as to have a concentration of 23.7% by mass, terminal methacrylate group-containing silicone resin X-22-164C (manufactured by Shin-Etsu Chemical Co., Ltd.) 0.6 parts by mass, 1.0 part by mass of photoradical generator Irgacure 907 (manufactured by Ciba Specialty Chemicals Co., Ltd.), 883.7 parts by mass of methyl ethyl ketone, and 29.3 parts by mass of cyclohexanone were added and stirred. The mixture was filtered through a PTFE filter having a pore diameter of 0.45 μm to prepare a coating solution for low refractive index layer (LL-64). The viscosity of the coating solution was 0.49 [mPa · sec], the surface tension was 24 [mN / m], and the amount of the coating solution applied to the transparent substrate was 5.0 [ml / m ² ]. .

(Preparation of coating solution for low refractive index layer (LL-65))
71.1 parts by mass of a solution obtained by dissolving the above copolymer P-3 in methyl ethyl ketone so as to have a concentration of 23.7% by mass, a terminal methacrylate group-containing silicone resin X-22-164C (manufactured by Shin-Etsu Chemical Co., Ltd.) 0.5 parts by mass, 0.8 parts by mass of photoradical generator Irgacure 907 (manufactured by Ciba Specialty Chemicals Co., Ltd.), 898.1 parts by mass of methyl ethyl ketone, and 29.5 parts by mass of cyclohexanone were added and stirred. The mixture was filtered through a PTFE filter having a pore diameter of 0.45 μm to prepare a coating solution for low refractive index layer (LL-65). The viscosity of the coating solution was 0.46 [mPa · sec], the surface tension was 24 [mN / m], and the amount of the coating solution applied to the transparent substrate was 6.0 [ml / m ² ]. .

The surface shapes of the antireflection films (11-1) to (11-5) prepared by changing the coating solution for the low refractive index layer to LL-61 to LL-65 were evaluated. The results are shown in Table 32. When the amount of the coating solution applied to the transparent substrate is 2 ml / m ² or more, the coating solution can be applied. However, when the amount is 1.5 ml / m ² , the entire surface cannot be applied uniformly, and an antireflection film is created. I couldn't. In addition, when the amount of the coating solution applied to the transparent substrate is 6 ml / m ² , the coating is possible, but since the amount of the coating solution is large, drying is not in time, and vertical streaky unevenness caused by the wind. Occurred on the entire surface.

[Evaluation of antireflection film]
The surface state of the obtained antireflection film was evaluated. Further, the average reflectance was measured in the same manner as in Example C-1.

(Surface shape)
The back surface of the film 1 m ² after coating all the layers was black-coated with magic ink, and then the uniformity of the density of the coated surface was visually evaluated.
○: Contrast difference is inconspicuous ×: Contrast difference is conspicuous

  When the display apparatus was created for the obtained antireflection films (11-1), (11-3), and (11-4) in the same procedure as in Examples C-9 and 10, examples produced with a gravure coater There was less color unevenness than the display devices of C-9 and 10, and the quality was high.

[Example C-12]
Antireflection films (12-1) to (12-5) were produced in the same manner as the antireflection film (11-1) except that the downstream lip land length ILO was changed to 10 μm, 30 μm, 70 μm, 100 μm, and 120 μm. The results are shown in Table 33. When the length of the downstream lip land is in the range of 30 μm to 100 μm, an antireflection film free from surface failure can be obtained. In the antireflection film (12-1), streaky unevenness occurs in the longitudinal direction of the base, and the antireflection film (12-5) cannot form the bead 14a at the same speed as the antireflection film (12-1). Application was impossible. Application was possible by reducing the application speed to half, but streaky irregularities occurred in the longitudinal direction of the base. When a display device was prepared for the antireflection films (12-2) to (12-4) in the same procedure as in Examples C-9 and 10, the background reflection was very small, and the color of the reflected light was significantly reduced. Furthermore, a display device with very high display quality in which uniformity within the display surface is ensured was obtained. On the other hand, when an antireflection film obtained from the antireflection films (12-1) and (12-5) is produced in the same procedure as in Examples C-9 and 10, color unevenness appears in the display device. It was visually recognized and could not be said to be high quality.

[Example C-13]
Coating is performed in the same manner as (11-1) except that the overcoating length L _O of the die coater is 0 μm, 30 μm, 120 μm, and 150 μm, and antireflection films (13-1) to (13-5) are produced. did. The results are shown in Table 34. When the overbite length is in the range of 30 μm to 120 μm, an antireflection film free from surface defects can be obtained. Application was possible with the antireflection film (13-1), but stepped unevenness was recognized in the base width direction when the surface shape was seen. Further, in the antireflection film (13-5), the bead 14a could not be formed at the same speed as (13-1), and the coating was impossible. Application was possible by reducing the application speed to half, but streaky irregularities occurred in the longitudinal direction of the base. In the antireflection films (13-2) to (13-4), when a display device was prepared in the same procedure as in Examples C-9 and 10, the background reflection was very small and the color of the reflected light was remarkably reduced. Furthermore, a display device with very high display quality in which uniformity within the display surface is ensured was obtained. On the other hand, when a display device is created with the antireflection films (13-1) and (13-5) in the same procedure as in Examples C-9 and 10, uneven coloring is visually recognized in the display device, and what is high quality? I could not say it.

(Embodiment of layer forming method (IV))
[Example D-1]
(Preparation of coating solution for hard coat layer)
The following composition was put into a mixing tank and stirred to obtain a hard coat layer coating solution.
750.0 parts by weight of trimethylolpropane triacrylate (Biscoat # 295 (manufactured by Osaka Organic Chemical Co., Ltd.)), 270.0 parts by mass of polyglycidyl methacrylate having a mass average molecular weight of 15000, 730.0 parts by mass of methyl ethyl ketone, 500.0 cyclohexanone Mass parts and 50.0 parts by mass of a photopolymerization initiator (Irgacure 184, Nippon Ciba Geigy Co., Ltd.) were added and stirred, and filtered through a polypropylene filter having a pore size of 0.4 μm to obtain a coating solution for a hard coat layer. Polyglycidyl methacrylate was prepared by dissolving glycidyl methacrylate (manufactured by Daicel Chemical Industries, Ltd.) in methyl ethyl ketone (MEK) and adding a thermal polymerization initiator (V-65 (manufactured by Wako Pure Chemical Industries, Ltd.)) dropwise. Reaction was performed at 80 ° C. for 2 hours, and the resulting reaction solution was dropped into hexane. , The precipitate obtained was dried under reduced pressure.

(Preparation of titanium dioxide fine particle dispersion)
As the titanium dioxide fine particles, titanium dioxide fine particles (MPT-129C, manufactured by Ishihara Sangyo Co., Ltd., TiO ₂ : Co ₃ O ₄ : containing cobalt and surface-treated with aluminum hydroxide and zirconium hydroxide: Al ₂ O ₃ : ZrO ₂ = 90.5: 3.0: 4.0: 0.5 weight ratio) was used.
The following dispersant (41.1 parts by mass) and cyclohexanone (701.8 parts by mass) were added to 257.1 parts by mass of the particles and dispersed by dynomill to prepare a titanium dioxide dispersion having a weight average diameter of 70 nm.
Dispersant

(Preparation of coating solution for medium refractive index layer)
In 99.1 parts by mass of the above titanium dioxide dispersion, 68.0 parts by mass of a mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (DPHA, manufactured by Nippon Kayaku Co., Ltd.), a photopolymerization initiator (Irgacure 907) 3.6 parts by mass, manufactured by Ciba Specialty Chemicals Co., Ltd., 1.2 parts by mass of photosensitizer (Kayacure DETX, manufactured by Nippon Kayaku Co., Ltd.), 279.6 parts by mass of methyl ethyl ketone, and 1049.0 of cyclohexanone. A part by mass was added and stirred. After sufficiently stirring, the solution was filtered through a polypropylene filter having a pore diameter of 0.4 μm to prepare a coating solution for a medium refractive index layer.

(Preparation of coating solution for high refractive index layer)
To 469.8 parts by mass of the above titanium dioxide dispersion, 40.0 parts by mass of a mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (DPHA, Nippon Kayaku Co., Ltd.), a photopolymerization initiator (Irgacure 907) 3.3 parts by mass, manufactured by Ciba Specialty Chemicals Co., Ltd., 1.1 parts by mass of photosensitizer (Kayacure-DETX, manufactured by Nippon Kayaku Co., Ltd.), 526.2 parts by mass of methyl ethyl ketone, and cyclohexanone 459 .6 parts by mass was added and stirred. The solution was filtered through a polypropylene filter having a pore diameter of 0.4 μm to prepare a coating solution for a high refractive index layer.

(Preparation of coating solution for low refractive index layer)
The copolymer P-3-1 described in the text of the present invention is dissolved in methyl isobutyl ketone so as to have a concentration of 7% by mass, and a terminal methacrylate group-containing silicone resin X-22-164C (manufactured by Shin-Etsu Chemical Co., Ltd.) ) 3% with respect to the solid content and 5% by mass of the photo radical generator Irgacure 907 (trade name) with respect to the solid content to prepare a coating solution for a low refractive index layer.

(Preparation of antireflection film 101)
A hard coat layer coating solution was applied onto a triacetyl cellulose film (TD-80UF, manufactured by Fuji Photo Film Co., Ltd.) having a thickness of 80 μm using a gravure coater. After drying at 100 ° C., an irradiance of 400 mW / cm using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) of 160 W / cm while purging with nitrogen so that the oxygen concentration becomes 1.0 vol% or less. ^{2. The} coating layer was cured by irradiating ultraviolet rays with an irradiation amount of 300 mJ / cm ² to form a hard coat layer having a thickness of 8 μm.
A medium refractive index layer coating solution, a high refractive index layer coating solution, and a low refractive index layer coating solution are coated on the hard coat layer at a speed of 5 to 100 m / min using a gravure coater having three coating stations. It was applied continuously.

The medium refractive index layer was dried at 90 ° C. for 30 seconds, and the ultraviolet curing condition was 180 W / cm air-cooled metal halide lamp (eye graphics) while purging with nitrogen so that the atmosphere had an oxygen concentration of 1.0% by volume or less. ), And the irradiation dose was 400 mW / cm ² and the irradiation dose was 400 mJ / cm ² .
The medium refractive index layer after curing had a refractive index of 1.630 and a film thickness of 67 nm.

The drying condition of the high refractive index layer is 90 ° C. for 30 seconds, and the ultraviolet curing condition is a 240 W / cm air-cooled metal halide lamp (eye graphics) while purging with nitrogen so that the atmosphere has an oxygen concentration of 1.0% by volume or less. ), And the irradiation dose was 600 mW / cm ² and the irradiation dose was 400 mJ / cm ² .
The cured high refractive index layer had a refractive index of 1.905 and a film thickness of 107 nm.

Drying conditions of the low refractive index layer 90 ° C., and 30 seconds, 1.40 m in the reaction chamber of the nitrogen purge (0.2 m ³ as the ultraviolet curing conditions the oxygen concentration falls below the ambient 0.1% by volume ³ / Using a 240 W / cm air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.), the irradiation amount was 600 mW / cm ² and the irradiation amount was 600 mJ / cm ² .
The low refractive index layer after curing had a refractive index of 1.440 and a film thickness of 85 nm. Thus, the antireflection film 101 was produced.
Only the curing conditions of the low refractive index layer were changed to the conditions shown in Table 35, and Samples 102 to 116 were produced. A continuous front chamber was provided immediately before the UV irradiation chamber, and nitrogen gas was blown there. The nozzle position was set so that the blown nitrogen gas directly hit the film surface. In addition, the irradiation chamber and the exhaust in the anterior chamber were adjusted so that an inert gas was blown out from the web entrance of the anterior chamber. The gap between the web entrance and the surface of the coating layer on the web was 4 mm.
The reaction rate was adjusted by changing the UV irradiation amount and the time until leaving the low oxygen zone.

  For the measurement of the polymerization reaction rate, only a low refractive index layer was coated on a polyethylene terephthalate film, and a sample was prepared by ionizing radiation curing under the above drying step and predetermined conditions. The sample was rubbed with KBr powder, and the rubbed KBr powder was finely mixed in a mortar, and the infrared absorption was measured. The measuring apparatus used was a FT-IR apparatus AVATAR360 manufactured by Nicole Co., Ltd., and the number of integrations was 40 times. The same measurement was performed on a sample that was not irradiated with ionizing radiation, and the ratio of the measured values obtained from the two samples was defined as the polymerization rate.

The following items were evaluated for the obtained film. The results are shown in Table 36.
[Specular reflectance]
An adapter ARV-474 is attached to a spectroscopic hardness meter V-550 (manufactured by JASCO Corporation), and the specular reflectance at an incident angle of -5 degrees is measured at an incident angle of 5 degrees in a wavelength range of 380 to 780 nm. The average reflectance at 650 nm was calculated and the antireflection property was evaluated.
[Pencil hardness]
The pencil hardness evaluation described in JIS K 5400 was performed. After conditioning the antireflection film at a temperature of 25 ° C. and a humidity of 60% RH for 2 hours, it was evaluated using the H-5H test pencil specified in JIS S 6006 at a load of 500 g as follows. The highest hardness that results in OK was taken as the evaluation value.
In evaluation of n = 5, there is no scratch to one scratch: OK
In evaluation of n = 5, 3 or more scratches: NG

[Steel wool scuff resistance]
The state of scratches was observed when a load of 1.96 N / cm ² was applied to steel steel of # 0000 and reciprocated 30 times, and the following five stages were evaluated.
◎: Scratch not found ○: Slightly invisible scratch △: Clearly visible scratch ×: Clearly visible scratch XX: Delamination of the film occurred thing

  From the curing conditions of the present invention, it can be seen that the antireflection film of the present invention is excellent in scratch resistance while having sufficient antireflection performance. By blowing nitrogen, the scratch resistance is excellent even if the oxygen concentration in the reaction chamber is the same.

[Example D-2]
In the preparation methods of Samples 102 and 110 of Example D-1, Samples 117 to 119 (the same method as Sample 102, except that the temperature was raised), which differed only in that the film surface temperature during ultraviolet irradiation was increased, 120 to 122 (same method as the sample 110 except that the temperature was raised) was prepared, and the same evaluation was performed.
The temperature of the film surface was adjusted by changing the temperature of the metal plate in contact with the film back surface.

In the present invention, by further increasing the film surface temperature during UV irradiation to 60 ° C. or higher, further excellent scratch resistance was obtained.
[Example D-3]
Samples 123 to 126 in Table 38 were prepared by changing the number of divisions of ultraviolet irradiation and the presence or absence of nitrogen substitution between the ultraviolet irradiations in the method for manufacturing the sample 102 prepared in Example D-1. These samples were evaluated in the same manner as in Example D-1.
In the ultraviolet irradiation division, the illuminance was adjusted so that the total irradiation amount was constant. The results are shown in Table 39.
It was found that, by dividing the ultraviolet irradiation and setting the illuminance for one time to an oxygen concentration of 3% by volume or less, the scratch resistance is not deteriorated and the high-speed production is suitable.

[Example D-4]
In the preparation method of the sample 102, the amount of nitrogen gas for purging is changed so that the gap between the front chamber entrance and the web surface of the front chamber and the flow of nitrogen gas on the entrance side are changed and the oxygen concentration in the ultraviolet irradiation chamber is constant at 0.1%. Were prepared, samples 127 to 130 were prepared, and the same evaluation as in Example D-1 was performed.
It was found that a low oxygen concentration can be maintained with a small amount of nitrogen gas by narrowing the gap and adjusting the exhaust gas so that the nitrogen gas at the inlet side of the web is slightly blown out.

[Example D-5]
In Examples D-1 to 4, the fluorine-containing polymer used in the coating solution for the low refractive index layer was changed to P-1-1 and P-2-1 described in the main text (equal mass replacement), and the same production and evaluation were performed. As a result, the same effects as in Examples D-1 to D-4 were obtained.

[Example D-6]
(Preparation of coating solution for hard coat layer)
The following composition was put into a mixing tank and stirred to obtain a hard coat layer coating solution.
─────────────────────────────────────
Coating composition for hard coat layer ─────────────────────────────────────
Desolite Z7404 100 parts by mass (Zirconia fine particle-containing hard coat composition liquid: solid content concentration 60 wt%, zirconia fine particle content 70 wt% to solid content, average particle diameter of about 20 nm, solvent composition MIBK: MEK = 9: 1,
(Made by JSR Corporation)
DPHA (UV curable resin: Nippon Kayaku Co., Ltd.) 31 parts by weight KBM-5103 (Silane coupling agent: Shin-Etsu Chemical Co., Ltd.)
10 parts by mass KE-P150 (1.5 μm silica particles: manufactured by Nippon Shokubai Co., Ltd.) 8.9 parts by mass MXS-300 (3 μm crosslinked PMMA particles: manufactured by Soken Chemical Co., Ltd.) 3.4 parts by mass MEK 29 parts by mass MIBK 13 parts by mass ─────────────────────────────────────

(Preparation of coating solution for low refractive index layer)
A coating solution for a low refractive index layer was prepared in the same manner as in Example D-1.

(Preparation of antireflection film 501)
As a transparent substrate, a triacetyl cellulose film (TD80U, manufactured by Fuji Photo Film Co., Ltd.) is unwound in a roll form, and the above coating liquid for hard coat layer has a gravure pattern of 135 lines / inch and a depth of 60 μm. Using a micro gravure roll with a diameter of 50 mm and a doctor blade, the coating was carried out at a conveyance speed of 10 m / min, dried at 60 ° C. for 150 seconds, and further under a nitrogen purge, a 160 W / cm air-cooled metal halide lamp (eye graphics ( Co., Ltd.) was used to cure the coating layer by irradiating ultraviolet rays with an illuminance of 400 mW / cm ² and an irradiation amount of 250 mJ / cm ² to form a hard coat layer 1 and wound it. After curing, the gravure roll rotation speed was adjusted so that the thickness of the hard coat layer was 3.6 μm.

The transparent base material coated with the hard coat layer was unwound again, and the coating liquid for the low refractive index layer was coated with a microgravure roll having a diameter of 200 lines / inch and a gravure pattern having a depth of 30 μm and a diameter of 50 mm and a doctor blade. Using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) with an oxygen concentration of 0.1% by volume after applying for 30 seconds at 90 ° C. and applying at a conveyance speed of 10 m / min. It was used to irradiate ultraviolet rays having an illuminance of 600 mW / cm ² and an irradiation amount of 400 mJ / cm ² to form a low refractive index layer and wind it up. After curing, the rotation speed of the gravure roll was adjusted so that the thickness of the low refractive index layer was 100 nm.

  Samples 502 to 516 were prepared by changing the curing conditions of the low refractive index layer as shown in Table 41.

These samples were evaluated in the same manner as in Example D-1. The results are shown in Table 42.
It can be seen that by the curing method of the present invention, excellent scratch resistance can be obtained while maintaining antireflection performance.

[Example D-7]
The low refractive index layer coating liquids of Examples D-1 to 6 were changed to the following low refractive index layer coating liquids A and B, respectively, and evaluations were made, and similar effects of the present invention could be confirmed.
By using the hollow silica particles, it was possible to produce a low-reflectance antireflection film with further excellent scratch resistance.

(Preparation of sol solution a)
A stirrer, a reactor equipped with a reflux condenser, 120 parts of methyl ethyl ketone, 100 parts of acryloyloxypropyltrimethoxysilane (KBM-5103, manufactured by Shin-Etsu Chemical Co., Ltd.), diisopropoxyaluminum ethyl acetoacetate (Kelope EP-12, After 3 parts of Hope Pharmaceutical Co., Ltd. were added and mixed, 30 parts of ion-exchanged water was added and reacted at 60 ° C. for 4 hours, and then cooled to room temperature to obtain sol solution a. The mass average molecular weight was 1600, and among the components higher than the oligomer component, the component having a molecular weight of 1000 to 20000 was 100%. Further, from the gas chromatography analysis, the raw material acryloyloxypropyltrimethoxysilane did not remain at all.

(Preparation of hollow silica fine particle dispersion)
Hollow silica fine particle sol (particle size about 40-50 nm, shell thickness 6-8 nm, refractive index 1.31, solid content concentration 20%, main solvent isopropyl alcohol, particle size according to Preparation Example 4 of JP-A-2002-79616 500 parts, 30 parts of acryloyloxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., KBM-5103), and diisopropoxyaluminum ethyl acetoacetate (Kelope EP-12, manufactured by Hope Pharmaceutical Co., Ltd.) ) After 1.5 parts were added and mixed, 9 parts of ion-exchanged water was added. After making it react at 60 degreeC for 8 hours, it cooled to room temperature and added 1.8 parts of acetylacetone, and obtained the hollow silica dispersion liquid. The resulting hollow silica dispersion had a solid content concentration of 18% by mass and a refractive index after solvent drying of 1.31.

(Preparation of coating solution A for low refractive index layer)
DPHA 3.3g
Hollow silica fine particle dispersion 40.0g
RMS-033 0.7g
Irgacure 907 0.2g
Sol liquid a 6.2g
Methyl ethyl ketone 290.6g
Cyclohexanone 9.0g

(Preparation of coating solution B for low refractive index layer)
DPHA 1.4g
Copolymer P-3-1 5.6g

Hollow silica fine particle dispersion 20.0g
RMS-033 0.7g
Irgacure 907 0.2g
Sol liquid a 6.2g
Methyl ethyl ketone 306.9g
Cyclohexanone 9.0g

The compounds used are shown below.
KBM-5103: Silane coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd.).
DPHA: A mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (manufactured by Nippon Kayaku Co., Ltd.)
RMS-033: Reactive silicone (manufactured by Gelest Co., Ltd.)
Irgacure 907: Photopolymerization initiator (Ciba Specialty Chemicals Co., Ltd.)

[Example D-8]
(Preparation of protective film for polarizing plate)
A saponification solution in which a 1.5 mol / L sodium hydroxide aqueous solution was kept at 50 ° C. was prepared. Furthermore, a 0.005 mol / L dilute sulfuric acid aqueous solution was prepared.
In the antireflection films prepared in Examples D-1 to 7, the surface of the transparent substrate opposite to the side having the low refractive index layer of the present invention was saponified using the saponification solution.
The aqueous sodium hydroxide solution on the surface of the saponified transparent substrate is thoroughly washed with water, then washed with the above diluted sulfuric acid aqueous solution, and further, the diluted sulfuric acid aqueous solution is thoroughly washed with water and sufficiently dried at 100 ° C. It was.
When the contact angle of the surface of the saponified transparent substrate on the side opposite to the side having the low refractive index layer of the antireflection film was evaluated, it was 40 degrees or less. Thus, the protective film for polarizing plates was produced.

(Preparation of polarizing plate)
A polyvinyl alcohol film having a thickness of 75 μm (manufactured by Kuraray Co., Ltd.) was immersed in an aqueous solution consisting of 1000 parts by mass of water, 7 parts by mass of iodine, and 105 parts by mass of potassium iodide to adsorb iodine.
Subsequently, this film was uniaxially stretched 4.4 times in the longitudinal direction in a 4% by mass boric acid aqueous solution, and then dried in a tension state to produce a polarizing film.
A saponified triacetyl cellulose surface of the antireflection film of the present invention (protective film for polarizing plate) was bonded to one surface of the polarizing film using a polyvinyl alcohol-based adhesive as an adhesive. Further, a triacetyl cellulose film saponified in the same manner as described above was bonded to the other surface of the polarizing film using the same polyvinyl alcohol-based adhesive.

(Evaluation of image display device)
The TN, STN, IPS, VA, OCB mode transmission type, reflection type, or transflective type in which the polarizing plate of the present invention thus prepared is mounted so that the antireflection film is the outermost surface of the display. The liquid crystal display device was excellent in antireflection performance and extremely excellent in visibility. In particular, the effect is remarkable in the VA mode.

[Example D-9]
(Preparation of polarizing plate)
In an optical compensation film having an optical compensation layer (Wide View Film SA 12B, manufactured by Fuji Photo Film Co., Ltd.), the surface opposite to the side having the optical compensation layer is saponified under the same conditions as in Example D-8. did.
Using the polyvinyl alcohol-based adhesive as the adhesive for the polarizing film prepared in Example D-8, the antireflection film (protecting plate for polarizing plate) prepared in Examples D-1 to 7 on one surface of the polarizing film The saponified triacetyl cellulose surfaces of the film) were bonded together. Further, the triacetyl cellulose surface of the saponified optical compensation film was bonded to the other surface of the polarizing film using the same polyvinyl alcohol adhesive.

(Evaluation of image display device)
The TN, STN, IPS, VA, OCB mode transmission type, reflection type, or transflective type in which the polarizing plate of the present invention thus prepared is mounted so that the antireflection film is the outermost surface of the display. The liquid crystal display device has better contrast in the bright room than the liquid crystal display device equipped with a polarizing plate that does not use an optical compensation film, has a very wide viewing angle in the vertical and horizontal directions, and has excellent antireflection performance and extremely high visibility. The display and display quality were excellent.
In particular, the effect is remarkable in the VA mode.
[Example D-10]
In the production method of the antireflection film 103, the coating solution formulation of the low refractive index layer was changed to LL-61, and coating was performed at a coating speed of 25 m / min using the following die coater. Thereafter, the film was dried at 90 ° C. for 30 seconds, and then irradiated with ultraviolet rays under the same conditions as the antireflection film 103 to form a low refractive index layer (refractive index 1.45, film thickness 83 nm). In this way, an antireflection film (10-1) was produced.
Furthermore, the antireflective films (10-2) to (10-5) were produced by changing the low refractive index layer coating solution to LL-62 to 65.

(Die coater configuration)
The slot die 13 has an upstream lip land length I _UP of 0.5 mm, a downstream lip land length I _LO of 50 μm, a length of the opening of the slot 16 in the web running direction of 150 μm, and a length of the slot 16 of 50 mm. I used one. The gap between the upstream lip land 18a and the web 12 is 50 μm longer than the gap between the downstream lip land 18b and the web 12 (hereinafter referred to as an overbite length of 50 μm), and the gap between the downstream lip land 18b and the web 12 is set. _GL was set to 50 μm. Further, the gap G _B between the gap G _S, and the back plate 40a and the web 12 between the side plate 40b and the web 12 of the decompression chamber 40 were both 200 [mu] m.

(Preparation of coating solution for low refractive index layer (LL-61))
152.4 parts by mass of a solution prepared by dissolving the following copolymer in methyl ethyl ketone so as to have a concentration of 23.7% by mass, 1.1 mass of a terminal methacrylate group-containing silicone resin X-22-164C (manufactured by Shin-Etsu Chemical Co., Ltd.) Part, 1.8 parts by mass of photoradical generator Irgacure 907 (trade name), 815.9 parts by mass of methyl ethyl ketone, and 28.8 parts by mass of cyclohexanone were added and stirred. The mixture was filtered through a PTFE filter having a pore diameter of 0.45 μm to prepare a coating solution for low refractive index layer (LL-61). The viscosity of the coating solution was 0.61 [mPa · sec], the surface tension was 24 [mN / m], and the amount of the coating solution applied to the transparent support was 2.8 [ml / m ² ]. .

(Preparation of coating solution for low refractive index layer (LL-62))
426.6 parts by mass of a solution obtained by dissolving the above copolymer in methyl ethyl ketone so as to have a concentration of 23.7% by mass, terminal methacrylate group-containing silicone resin X-22-164C (manufactured by Shin-Etsu Chemical Co., Ltd.) 3.0 Mass parts, 5.1 parts by mass of photoradical generator Irgacure 907 (trade name), 538.6 parts by mass of methyl ethyl ketone, and 26.7 parts by mass of cyclohexanone were added and stirred. The mixture was filtered through a PTFE filter having a pore diameter of 0.45 μm to prepare a coating solution for low refractive index layer (LL-62). The viscosity of the coating solution was 1.0 [mPa · sec], the surface tension was 24 [mN / m], and the amount of the coating solution applied to the transparent support was 1.5 [ml / m ² ]. .

(Preparation of coating solution for low refractive index layer (LL-63))
213.3 parts by mass of a solution obtained by dissolving the above copolymer in methyl ethyl ketone to a concentration of 23.7% by mass, terminal methacrylate group-containing silicone resin X-22-164C (manufactured by Shin-Etsu Chemical Co., Ltd.) 1.5 Mass parts, 2.5 parts by mass of photoradical generator Irgacure 907 (trade name), 754.3 parts by mass of methyl ethyl ketone, and 28.4 parts by mass of cyclohexanone were added and stirred. The mixture was filtered through a PTFE filter having a pore diameter of 0.45 μm to prepare a coating solution for low refractive index layer (LL-63). The viscosity of the coating solution was 0.76 [mPa · sec], the surface tension was 24 [mN / m], and the amount of the coating solution applied to the transparent support was 2.0 [ml / m ² ]. .

(Preparation of coating solution for low refractive index layer (LL-64))
85.3 parts by mass of a solution obtained by dissolving the above copolymer in methyl ethyl ketone so as to have a concentration of 23.7% by mass, terminal methacrylate group-containing silicone resin X-22-164C (manufactured by Shin-Etsu Chemical Co., Ltd.) 0.6 1 part by mass, 1.0 part by mass of photoradical generator Irgacure 907 (trade name), 883.7 parts by mass of methyl ethyl ketone, and 29.3 parts by mass of cyclohexanone were added and stirred. The mixture was filtered through a PTFE filter having a pore diameter of 0.45 μm to prepare a coating solution for low refractive index layer (LL-64). The viscosity of the coating solution was 0.49 [mPa · sec], the surface tension was 24 [mN / m], and the amount of the coating solution applied to the transparent support was 5.0 [ml / m ² ]. .

(Preparation of coating solution for low refractive index layer (LL-65))
71.1 parts by mass of a solution obtained by dissolving the above copolymer in methyl ethyl ketone to a concentration of 23.7% by mass, terminal methacrylate group-containing silicone resin X-22-164C (manufactured by Shin-Etsu Chemical Co., Ltd.) 0.5 Mass parts, 0.8 parts by mass of photoradical generator Irgacure 907 (trade name), 898.1 parts by mass of methyl ethyl ketone, and 29.5 parts by mass of cyclohexanone were added and stirred. The mixture was filtered through a PTFE filter having a pore diameter of 0.45 μm to prepare a coating solution for low refractive index layer (LL-65). The viscosity of the coating solution was 0.46 [mPa · sec], the surface tension was 24 [mN / m], and the amount of the coating solution applied to the transparent support was 6.0 [ml / m ² ]. .

The surface condition when the coating solution for the low refractive index layer was changed to LL-61 to LL-65 was evaluated. The results are shown in Table 43. When the amount of the coating solution applied to the transparent support is 2 ml / m ² or more, it is possible to apply the coating solution, but at 1.5 ml / m ² , the entire surface cannot be applied uniformly and an antireflection film is created. I couldn't. In addition, when the amount of the coating solution to be applied to the transparent support is 6 ml / m ² , the coating is possible, but since the amount of the coating solution is large, drying is not in time, and vertical streaky unevenness caused by the wind. Occurred on the entire surface.

[Evaluation of antireflection film]
The surface state of the obtained antireflection film was evaluated. Further, the average reflectance was measured in the same manner as in Example D-1.

(Surface shape)
The back surface of the film 1 m ² after coating all the layers was black-coated with magic ink, and then the uniformity of the density of the coated surface was visually evaluated.
○: Contrast difference is inconspicuous ×: Contrast difference is conspicuous

  When the display apparatus was produced for the obtained antireflection film (10-1), (10-3), (10-4) in the same procedure as Example D-8 and 9, the Example produced with the gravure coater. There was less color unevenness and higher quality than the display devices of D-8 and 9.

[Example D-11]
Antireflection films (11-1) to (11-5) were produced in the same manner as the antireflection film (10-1) except that the downstream lip land length IL0 was changed to 10 μm, 30 μm, 70 μm, 100 μm, and 120 μm. The results are shown in Table 44. When the length of the downstream lip land is in the range of 30 μm to 100 μm, an antireflection film free from surface failure can be obtained. In the antireflection film (11-1), streaky unevenness occurs in the longitudinal direction of the base, and the antireflection film (11-5) cannot form the beads 14a at the same speed as the antireflection film (11-1). Application was impossible. Application was possible by reducing the application speed to half, but streaky irregularities occurred in the longitudinal direction of the base. When a display device was prepared for the antireflection films (11-2) to (11-4) in the same manner as in Examples D-8 and 9, there was very little reflection of the background, and the color of the reflected light was significantly reduced. Furthermore, a display device with very high display quality in which uniformity within the display surface is ensured was obtained. On the other hand, when an antireflection film obtained from the antireflection films (11-1) and (11-5) is produced in the same procedure as in Examples D-8 and 9, color unevenness is found in the display device. It is visually recognized and cannot be said to be high quality.

[Example D-12]
Coating was performed in the same manner as (10-1) except that the overcoating length LO of the die coater was 0 μm, 30 μm, 120 μm, and 150 μm, and antireflection films (12-1) to (12-5) were produced. . The results are shown in Table 45. When the overbite length is in the range of 30 μm to 120 μm, an antireflection film free from surface defects can be obtained. Application was possible with the antireflection film (12-1), but stepped unevenness was recognized in the base width direction when the surface shape was seen. Further, in the antireflection film (12-5), the bead 14a could not be formed at the same speed as (12-1), and the coating was impossible. Application was possible by reducing the application speed to half, but streaky irregularities occurred in the longitudinal direction of the base. In the antireflection films (12-2) to (12-4), when a display device was prepared in the same procedure as in Examples D-8 and 9, there was very little reflection of the background, and the color of reflected light was significantly reduced. Furthermore, a display device with very high display quality in which uniformity within the display surface is ensured was obtained. On the other hand, when a display device is created with the same procedures as in Examples D-8 and 9 using the antireflection films (12-1) and (12-5), uneven coloring is visually recognized in the display device, and what is high quality? I could not say it.

(Embodiment of layer forming method (V))
[Example E-1]
(Preparation of coating solution for hard coat layer)
The following composition was put into a mixing tank and stirred to obtain a hard coat layer coating solution.
750.0 parts by weight of trimethylolpropane triacrylate (Biscoat # 295 (manufactured by Osaka Organic Chemical Co., Ltd.)), 270.0 parts by weight of polyglycidyl methacrylate having a mass average molecular weight of 15000, 730.0 parts by weight of methyl ethyl ketone, 500.0 cyclohexanone Mass parts and 50.0 parts by mass of a photopolymerization initiator (Irgacure 184, manufactured by Ciba Specialty Chemicals Co., Ltd.) were added and stirred, and filtered through a polypropylene filter having a pore size of 0.4 μm for the hard coat layer. The polyglycidyl methacrylate was dissolved in methyl ethyl ketone (MEK) and reacted at 80 ° C. for 2 hours while dropwise adding a thermal polymerization initiator V-65 (manufactured by Wako Pure Chemical Industries, Ltd.). The resulting reaction solution was added dropwise to hexane, and the precipitate It was obtained by drying under reduced pressure.

(Preparation of titanium dioxide fine particle dispersion)
As the titanium dioxide fine particles, titanium dioxide fine particles (MPT-129C, manufactured by Ishihara Sangyo Co., Ltd., TiO ₂ : Co ₃ O ₄ : containing cobalt and subjected to surface treatment using aluminum hydroxide and zirconium hydroxide: Al ₂ O ₃ : ZrO ₂ = 90.5: 3.0: 4.0: 0.5 weight ratio) was used.
The following dispersant (41.1 parts by mass) and cyclohexanone (701.8 parts by mass) were added to 257.1 parts by mass of the particles and dispersed by dynomill to prepare a titanium dioxide dispersion having a weight average diameter of 70 nm.

Dispersant

(Preparation of coating solution for medium refractive index layer)
In 99.1 parts by mass of the above titanium dioxide dispersion, 68.0 parts by mass of a mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (DPHA, manufactured by Nippon Kayaku Co., Ltd.), a photopolymerization initiator (Irgacure 907) 3.6 parts by mass, manufactured by Ciba Specialty Chemicals Co., Ltd., 1.2 parts by mass of photosensitizer (Kayacure DETX, manufactured by Nippon Kayaku Co., Ltd.), 279.6 parts by mass of methyl ethyl ketone, and 1049.0 of cyclohexanone. A part by mass was added and stirred. After sufficiently stirring, the solution was filtered through a polypropylene filter having a pore diameter of 0.4 μm to prepare a coating solution for a medium refractive index layer.

(Preparation of coating solution for high refractive index layer)
To 469.8 parts by mass of the above titanium dioxide dispersion, 40.0 parts by mass of a mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (DPHA, Nippon Kayaku Co., Ltd.), a photopolymerization initiator (Irgacure 907) 3.3 parts by mass, manufactured by Ciba Specialty Chemicals Co., Ltd., 1.1 parts by mass of photosensitizer (Kayacure DETX, manufactured by Nippon Kayaku Co., Ltd.), 526.2 parts by mass of methyl ethyl ketone, and cyclohexanone 459. 6 parts by mass was added and stirred. The solution was filtered through a polypropylene filter having a pore diameter of 0.4 μm to prepare a coating solution for a high refractive index layer.

(Preparation of coating solution for low refractive index layer)
The copolymer P-3 described in the present invention is dissolved in methyl isobutyl ketone so as to have a concentration of 7% by mass, and a terminal methacrylate group-containing silicone resin X-22-164C (manufactured by Shin-Etsu Chemical Co., Ltd.) 3% of the solid content and 5% by mass of the photo radical generator Irgacure 907 (trade name) based on the solid content were prepared to prepare a coating solution for a low refractive index layer.

(Preparation of antireflection film 101)
A hard coat layer coating solution was applied onto a triacetyl cellulose film (TD80UF, manufactured by Fuji Photo Film Co., Ltd.) having a thickness of 80 μm using a gravure coater. After drying at 100 ° C., an irradiance of 400 mW / cm using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) of 160 W / cm while purging with nitrogen so that the oxygen concentration becomes 1.0 vol% or less. ^{2. The} coating layer was cured by irradiating ultraviolet rays with an irradiation amount of 300 mJ / cm ² to form a hard coat layer having a thickness of 8 μm.
A medium refractive index layer coating solution, a high refractive index layer coating solution, and a low refractive index layer coating solution on a hard coat layer at a speed of 5 to 100 m / min using a gravure coater having three coating stations. It was applied continuously.

The medium refractive index layer was dried at 90 ° C. for 30 seconds, and the ultraviolet curing condition was 180 W / cm air-cooled metal halide lamp (eye graphics) while purging with nitrogen so that the atmosphere had an oxygen concentration of 1.0% by volume or less. ), And the irradiation dose was 200 mW / cm ² and the irradiation dose was 200 mJ / cm ² .
The medium refractive index layer after curing had a refractive index of 1.630 and a film thickness of 67 nm.

The drying condition of the high refractive index layer is 90 ° C. for 30 seconds, and the ultraviolet curing condition is a 240 W / cm air-cooled metal halide lamp (eye graphics) while purging with nitrogen so that the atmosphere has an oxygen concentration of 1.0% by volume or less. ), And the irradiation dose was 600 mW / cm ² and the irradiation dose was 400 mJ / cm ² .
The cured high refractive index layer had a refractive index of 1.905 and a film thickness of 107 nm.

The drying condition of the low refractive index layer is 90 ° C. for 30 seconds, and the ultraviolet curing condition is nitrogen purge (in a 0.2 m ³ reaction chamber, 1.40 m ³ / Using a 240 W / cm air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.), the irradiation amount was 200 mW / cm ² and the irradiation amount was 200 mJ / cm ² .
The low refractive index layer after curing had a refractive index of 1.440 and a film thickness of 85 nm. Thus, the antireflection film 101 was produced.
Samples 102 to 116 were prepared by changing the initiator type and curing conditions of the low refractive index layer to those shown in Table 46. The amount of initiator was replaced by this weight. Nitrogen gas was blown by providing a front chamber continuous immediately before the UV irradiation chamber, and setting the position of the nozzle so that the inert gas directly hit the film surface. In addition, the irradiation chamber and the exhaust in the anterior chamber were adjusted so that an inert gas was blown out from the web entrance of the anterior chamber. The gap between the web entrance and the web surface was 4 mm.
The ultraviolet irradiation amount when the coating speed was changed was set so that the irradiation amount became constant by changing the illuminance.

In addition, the said exemplary compound 21 grade | etc., Has already been described in this specification as a compound (1-21) as described in Unexamined-Japanese-Patent No. 2000-80068. In particular, the exemplified compound 21 is described below again.
(Exemplary Compound 21)

The following items were evaluated for the obtained film. The results are shown in Table 47.
[Specular reflectance]
A spectroscopic hardness meter V-550 (manufactured by JASCO Corporation) is fitted with an adapter ARV-474, and the specular reflectance at an incident angle of -5 degrees at an incident angle of 5 degrees is measured in a wavelength range of 380 to 780 nm. The average reflectance at 650 nm was calculated and the antireflection property was evaluated.
[Pencil hardness]
The pencil hardness evaluation described in JIS K 5400 was performed. After conditioning the antireflection film at a temperature of 25 ° C. and a humidity of 60% RH for 2 hours, it was evaluated using the H-5H test pencil specified in JIS S 6006 at a load of 500 g as follows. The highest hardness that results in OK was taken as the evaluation value.
In evaluation of n = 5, there is no scratch to one scratch: OK
In evaluation of n = 5, 3 or more scratches: NG

[Steel wool scuff resistance]
The state of scratches was observed when a load of 1.96 N / cm ² was applied to steel steel of # 0000 and reciprocated 30 times, and the following five stages were evaluated.
◎: Scratch not found ○: Slightly invisible scratch △: Clearly visible scratch ×: Clearly visible scratch XX: Delamination of the film occurred thing

  It can be seen that by using the initiator of the present invention and curing under the curing conditions of the present invention, the antireflection film has excellent antireflection performance while having sufficient antireflection performance. By blowing nitrogen, the scratch resistance is excellent even if the oxygen concentration in the reaction chamber is the same.

[Example E-2]
In the production methods of the samples 103 and 107 of Example E-1, samples 117 to 122 differing only in that the film temperature at the time of ultraviolet irradiation was increased were produced, and the same evaluation was performed.
The temperature of the film surface was adjusted by changing the temperature of the metal plate in contact with the back surface of the film.

  In the present invention, further superior scratch resistance was obtained by raising the temperature during UV irradiation to 60 ° C. or higher.

[Example E-3]
Samples 123 to 126 in Table 49 were prepared by changing the number of times of ultraviolet irradiation and the presence or absence of nitrogen substitution between the samples 107 prepared in Example E-1. These samples were evaluated in the same manner as in Example E-1.
In the ultraviolet irradiation division, the illuminance was adjusted so that the total irradiation amount was constant. The results are shown in Table 50.
By dividing the ultraviolet irradiation and setting the illuminance for one time to an oxygen concentration of 3% by volume or less, the deterioration of the scratch resistance is eliminated, and high-speed production suitability is achieved.

[Example E-4]
In the sample 107 manufacturing method manufactured in Example E-1, the gap with the web at the front chamber entrance and the flow of nitrogen gas at the entrance side were changed, and the oxygen concentration in the ultraviolet irradiation chamber was kept constant at 0.08%. The amount of purge nitrogen gas was adjusted to prepare samples 127 to 130, and the same evaluation as in Example E-1 was performed.
It can be seen that a low oxygen concentration can be maintained with a small amount of nitrogen gas by narrowing the gap and adjusting the exhaust gas so that the nitrogen gas at the inlet side of the web is slightly blown out.

[Example E-5]
As a result of performing the same evaluation by changing the fluorine-containing polymer used in the low refractive index layer in Examples E-1 to E-4 to P-1 and P-2 described in the text (equal mass replacement), Example E-1 The same effects as in -4 were obtained.

[Example E-6]
(Preparation of coating solution for hard coat layer)
The following composition was put into a mixing tank and stirred to obtain a hard coat layer coating solution.
───────────────────────────────────────
Coating solution composition for hard coat layer ───────────────────────────────────────
Desolite Z7404 100 parts by mass (Zirconia fine particle-containing hard coat composition liquid: solid content concentration 60 wt%,
Zirconia fine particle content 70 wt% vs. solid content, average particle diameter of about 20 nm,
(Solvent composition MIBK: MEK = 9: 1, manufactured by JSR Corporation)
DPHA (UV curable resin: Nippon Kayaku Co., Ltd.) 31 parts by weight KBM-5103 (Silane coupling agent: Shin-Etsu Chemical Co., Ltd.) 10 parts by weight KE-P150 (1.5 μm silica particles: Nippon Shokubai) 8.9 parts by mass MXS-300 (3 μm cross-linked PMMA particles: manufactured by Soken Chemical Co., Ltd.) 3.4 parts by mass Methyl ethyl ketone (MEK) 29 parts by mass Methyl isobutyl ketone (MIBK) 13 parts by mass ────────────────────────────────────

(Preparation of coating solution for low refractive index layer)
A coating solution for a low refractive index layer was prepared in the same manner as in Example E-1.

(Preparation of antireflection film 601)
A triacetyl cellulose film (TD80U, manufactured by Fuji Photo Film Co., Ltd.) is unwound in a roll form as a transparent substrate, and the above coating liquid for hard coat layer has a gravure pattern with 135 lines / inch and a depth of 60 μm. Using a micro gravure roll with a diameter of 50 mm and a doctor blade, the coating was carried out at a conveyance speed of 10 m / min, dried at 60 ° C. for 150 seconds, and further under a nitrogen purge, a 160 W / cm air-cooled metal halide lamp (eye graphics ( The coating layer was cured by irradiating with ultraviolet rays having an illuminance of 400 mW / cm ² and an irradiation amount of 250 mJ / cm ² , and the hard coat layer 1 was formed and wound. After curing, the gravure roll rotation speed was adjusted so that the thickness of the hard coat layer was 3.6 μm.

The transparent base material coated with the hard coat layer was unwound again, and the coating liquid for the low refractive index layer was coated with a microgravure roll having a diameter of 200 lines / inch and a gravure pattern having a depth of 30 μm and a diameter of 50 mm and a doctor blade. Using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) with an oxygen concentration of 0.1% by volume after applying for 30 seconds at 90 ° C. and applying at a conveyance speed of 10 m / min. It was used to irradiate ultraviolet rays having an illuminance of 600 mW / cm ² and an irradiation amount of 400 mJ / cm ² to form a low refractive index layer and wind it up. After curing, the rotation speed of the gravure roll was adjusted so that the thickness of the low refractive index layer was 100 nm. In the case of heating after ultraviolet irradiation, the film after irradiation was brought into contact with a rotating metal roll through which hot water or pressurized steam was passed.

  Samples 602 to 616 were prepared by changing the curing conditions of the low refractive index layer as shown in Table 52.

These samples were evaluated in the same manner as in Example E-1. The results are shown in Table 53.
It can be seen that by the curing method of the present invention, excellent scratch resistance can be obtained while maintaining antireflection performance.

[Example E-7]
The low-refractive index layers of Examples E-1 to 6 were changed to the following low-refractive index layers A and B, respectively, and evaluation was performed, and similar effects of the present invention could be confirmed.
By using the hollow silica particles, it was possible to produce a low-reflectance antireflection film with further excellent scratch resistance.

(Preparation of sol solution a)
A stirrer, a reactor equipped with a reflux condenser, 120 parts of methyl ethyl ketone, 100 parts of acryloyloxypropyltrimethoxysilane (KBM-5103, manufactured by Shin-Etsu Chemical Co., Ltd.), 3 parts of diisopropoxyaluminum ethyl acetoacetate were added and mixed. Thereafter, 30 parts of ion-exchanged water was added and reacted at 60 ° C. for 4 hours, and then cooled to room temperature to obtain sol solution a. The mass average molecular weight was 1600, and among the components higher than the oligomer component, the component having a molecular weight of 1000 to 20000 was 100%. Further, from the gas chromatography analysis, the raw material acryloyloxypropyltrimethoxysilane did not remain at all.

(Preparation of hollow silica fine particle dispersion)
Hollow silica fine particle sol (particle size about 40-50 nm, shell thickness 6-8 nm, refractive index 1.31, solid content concentration 20%, main solvent isopropyl alcohol, particle size according to Preparation Example 4 of JP-A-2002-79616 500 parts, acryloyloxypropyltrimethoxysilane (Shin-Etsu Chemical Co., Ltd., KBM-5103) 30 parts, and diisopropoxyaluminum ethyl acetoacetate (Kelope EP-12, manufactured by Hope Pharmaceutical Co., Ltd.) ) After 1.5 parts were added and mixed, 9 parts of ion-exchanged water was added. After making it react at 60 degreeC for 8 hours, it cooled to room temperature and added 1.8 parts of acetylacetone, and obtained the hollow silica dispersion liquid. The resulting hollow silica dispersion had a solid content concentration of 18% by mass and a refractive index after solvent drying of 1.31.

(Preparation of coating solution A for low refractive index layer)
DPHA 3.3g
Hollow silica fine particle dispersion 40.0g
RMS-033 0.7g
Illustrative Compound 21 0.2g
Sol liquid a 6.2g
Methyl ethyl ketone 290.6g
Cyclohexanone 9.0g

(Preparation of coating solution B for low refractive index layer)
DPHA 1.4g
Copolymer P-3 5.6 g
Hollow silica fine particle dispersion 20.0g
RMS-033 0.7g
Illustrative Compound 21 0.2g
Sol liquid a 6.2g
Methyl ethyl ketone 306.9g
Cyclohexanone 9.0g

The compounds used are shown below.
KBM-5103: Silane coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd.).
DPHA: A mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (manufactured by Nippon Kayaku Co., Ltd.)
RMS-033: Reactive silicone (manufactured by Gelest Co., Ltd.)

[Example E-8]
The low refractive index layers of Examples E-1 to 7 were respectively changed to the following low refractive index layers C and evaluated, and the same effects of the present invention could be confirmed. The same effect was also obtained with a low refractive index layer in which OPSTA JN7228A was replaced with JTA113 (manufactured by JSR Co., Ltd.) having a higher degree of cross-linking with equal weight.
(Preparation of sol solution a)
A reactor equipped with a stirrer and a reflux condenser, 120 parts of methyl ethyl ketone, 100 parts of acryloyloxypropyltrimethoxysilane (KBM5103 (trade name); manufactured by Shin-Etsu Chemical Co., Ltd.), diisopropoxyaluminum ethyl acetoacetate (Kelope EP-12, After 3 parts of Hope Pharmaceutical Co., Ltd. were added and mixed, 30 parts of ion-exchanged water was added and reacted at 60 ° C. for 4 hours, and then cooled to room temperature to obtain sol solution a. The mass average molecular weight was 1800, and among the components higher than the oligomer component, the component having a molecular weight of 1000 to 20000 was 100%. Further, from the gas chromatography analysis, the raw material acryloyloxypropyltrimethoxysilane did not remain at all.

(Preparation of coating solution C for low refractive index layer)
The following composition was put into a mixing tank, stirred, and then filtered through a polypropylene filter having a pore size of 1 μm to prepare a coating solution C for a low refractive index layer.
───────────────────────────────────────
Composition C for low refractive index layer ───────────────────────────────────────
OPSTAR JN7228A (Polysiloxane and hydroxyl group-containing thermally crosslinkable fluorine-containing polymer composition solution: manufactured by JSR Corporation) 100 parts by mass MEK-ST
(Silica dispersion average particle size 15 nm: manufactured by Nissan Chemical Co., Ltd.) 4.3 parts by mass MEK-ST-L (MEK-ST different diameter product)
(Silica dispersion average particle size 45 nm: manufactured by Nissan Chemical Co., Ltd.) 5.1 parts by mass Sol solution a 2.2 parts by mass Exemplary compound 21 5.0 parts by mass Methyl ethyl ketone 15 parts by mass Cyclohexanone 3.6 parts by mass ────────────────────────────────────

The low-refractive index layer coating liquid C was applied at a conveyance speed of 10 m / min using a microgravure roll with a diameter of 50 mm and a doctor blade having a gravure pattern of 200 lines / inch and a depth of 30 μm, and 120 ° C. After drying for 150 seconds at 140 ° C. for 12 minutes, using a 240 W / cm air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) under a nitrogen purge, an illuminance of 200 mW / cm ² and an irradiation amount of 450 mJ / Cm ² of ultraviolet light was irradiated to form a low refractive index layer and wound up. After curing, the rotation speed of the gravure roll was adjusted so that the thickness of the low refractive index layer was 100 nm [Example E-9]
(Preparation of protective film for polarizing plate)
A saponification solution in which a 1.5 mol / L sodium hydroxide aqueous solution was kept at 50 ° C. was prepared.
Further, a 0.005 mol / L dilute sulfuric acid aqueous solution was prepared.
In the antireflection films produced in Examples E-1 to 7, the surface of the transparent substrate opposite to the side having the high refractive index layer of the present invention was saponified using the saponification solution.
The aqueous sodium hydroxide solution on the surface of the saponified transparent substrate is thoroughly washed with water, then washed with the above diluted sulfuric acid aqueous solution, and further, the diluted sulfuric acid aqueous solution is thoroughly washed with water and sufficiently dried at 100 ° C. It was.
When the contact angle of the surface of the saponified transparent substrate on the side opposite to the side having the high refractive index layer of the antireflection film was evaluated, it was 40 degrees or less. Thus, the protective film for polarizing plates was produced.

(Preparation of polarizing plate)
A polyvinyl alcohol film having a thickness of 75 μm (manufactured by Kuraray Co., Ltd.) was immersed in an aqueous solution consisting of 1000 parts by mass of water, 7 parts by mass of iodine, and 105 parts by mass of potassium iodide to adsorb iodine.
Subsequently, this film was uniaxially stretched 4.4 times in the longitudinal direction in a 4% by mass boric acid aqueous solution, and then dried in a tension state to produce a polarizing film.
A saponified triacetyl cellulose surface of the antireflection film of the present invention (protective film for polarizing plate) was bonded to one surface of the polarizing film using a polyvinyl alcohol-based adhesive as an adhesive. Further, a triacetyl cellulose film saponified in the same manner as described above was bonded to the other surface of the polarizing film using the same polyvinyl alcohol-based adhesive.

(Evaluation of image display device)
The TN, STN, IPS, VA, OCB mode transmission type, reflection type, or transflective type in which the polarizing plate of the present invention thus prepared is mounted so that the antireflection film is the outermost surface of the display. The liquid crystal display device was excellent in antireflection performance and extremely excellent in visibility. In particular, the effect is remarkable in the VA mode.

[Example E-10]
(Preparation of polarizing plate)
In an optical compensation film having an optical compensation layer (wide view film SA 12B, manufactured by Fuji Photo Film Co., Ltd.), the surface opposite to the side having the optical compensation layer is saponified under the same conditions as in Example E-4. did.
Using the polyvinyl alcohol adhesive as the adhesive for the polarizing film prepared in Example E-9, the antireflection film (protecting plate for polarizing plate) prepared in Examples E-1 to 7 on one surface of the polarizing film The saponified triacetyl cellulose surfaces of the film) were bonded together. Further, the triacetyl cellulose surface of the saponified optical compensation film was bonded to the other surface of the polarizing film using the same polyvinyl alcohol adhesive.

(Evaluation of image display device)
The TN, STN, IPS, VA, OCB mode transmission type, reflection type, or transflective type in which the polarizing plate of the present invention thus prepared is mounted so that the antireflection film is the outermost surface of the display. The liquid crystal display device has better contrast in the bright room than the liquid crystal display device equipped with a polarizing plate that does not use an optical compensation film, has a very wide viewing angle in the vertical and horizontal directions, and has excellent antireflection performance and extremely high visibility. The display and display quality were excellent.
In particular, the effect is remarkable in the VA mode.

[Example E-11]
In the production method of the antireflection film of Example E-1, the coating solution formulation of the low refractive index layer was changed to LL-61 below, and coating was performed at a coating speed of 25 m / min using the following die coater. Then, after drying at 90 ° C. for 30 seconds, using a 240 W / cm air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) while purging with nitrogen so that the atmosphere has an oxygen concentration of 0.1% by volume or less, An ultraviolet ray having an illuminance of 600 mW / cm ² and an irradiation amount of 400 mJ / cm ² was irradiated to form a low refractive index layer (refractive index 1.45, film thickness 83 nm). In this way, an antireflection film (11-1) was produced.
Furthermore, the antireflective films (11-2) to (11-5) were produced by changing the low refractive index layer coating solution to the following LL-62 to 65.

(Die coater configuration)
The slot die 13 has an upstream lip land length I _UP of 0.5 mm, a downstream lip land length I _LO of 50 μm, a length of the opening of the slot 16 in the web running direction of 150 μm, and a length of the slot 16 of 50 mm. I used one. The gap between the upstream lip land 18a and the web 12 is 50 μm longer than the gap between the downstream lip land 18b and the web 12 (hereinafter referred to as an overbite length of 50 μm), and the gap between the downstream lip land 18b and the web 12 is set. _GL was set to 50 μm. Further, the gap G _B between the gap G _S, and the back plate 40a and the web 12 between the side plate 40b and the web 12 of the decompression chamber 40 were both 200 [mu] m.

(Preparation of coating solution for low refractive index layer (LL-61))
152.4 parts by mass of a solution obtained by dissolving the following fluorine-containing copolymer in methyl ethyl ketone so as to have a concentration of 23.7% by mass, a terminal methacrylate group-containing silicone resin X-22-164C (manufactured by Shin-Etsu Chemical Co., Ltd.) 1 0.1 part by mass, 1.8 parts by mass of a photoradical generator (Exemplary Compound 21), 815.9 parts by mass of methyl ethyl ketone, and 28.8 parts by mass of cyclohexanone were added and stirred. The mixture was filtered through a PTFE filter having a pore diameter of 0.45 μm to prepare a coating solution for low refractive index layer (LL-61). The viscosity of the coating solution was 0.61 [mPa · sec], the surface tension was 24 [mN / m], and the amount of the coating solution applied to the transparent support was 2.8 [ml / m ² ]. .

(Preparation of coating solution for low refractive index layer (LL-62))
426.6 parts by mass of a solution obtained by dissolving the above fluorinated copolymer in methyl ethyl ketone to a concentration of 23.7% by mass, terminal methacrylate group-containing silicone resin X-22-164C (manufactured by Shin-Etsu Chemical Co., Ltd.) 3 0.0 parts by mass, 5.1 parts by mass of a photo radical generator (Exemplary Compound 21), 538.6 parts by mass of methyl ethyl ketone, and 26.7 parts by mass of cyclohexanone were added and stirred. The mixture was filtered through a PTFE filter having a pore diameter of 0.45 μm to prepare a coating solution for low refractive index layer (LL-62). The viscosity of the coating solution was 1.0 [mPa · sec], the surface tension was 24 [mN / m], and the amount of the coating solution applied to the transparent support was 1.5 [ml / m ² ]. .

(Preparation of coating solution for low refractive index layer (LL-63))
213.3 parts by mass of a solution obtained by dissolving the above fluorinated copolymer in methyl ethyl ketone so as to have a concentration of 23.7% by mass, a terminal methacrylate group-containing silicone resin X-22-164C (manufactured by Shin-Etsu Chemical Co., Ltd.) 1 0.5 parts by mass, 2.5 parts by mass of a photo radical generator (Exemplary Compound 21), 754.3 parts by mass of methyl ethyl ketone, and 28.4 parts by mass of cyclohexanone were added and stirred. The mixture was filtered through a PTFE filter having a pore diameter of 0.45 μm to prepare a coating solution for low refractive index layer (LL-63). The viscosity of the coating solution was 0.76 [mPa · sec], the surface tension was 24 [mN / m], and the amount of the coating solution applied to the transparent support was 2.0 [ml / m ² ]. .

(Preparation of coating solution for low refractive index layer (LL-64))
85.3 parts by mass of a solution obtained by dissolving the above fluorinated copolymer in methyl ethyl ketone so as to have a concentration of 23.7% by mass, a terminal methacrylate group-containing silicone resin X-22-164C (manufactured by Shin-Etsu Chemical Co., Ltd.) 0 .6 parts by mass, 1.0 part by mass of a photoradical generator (Exemplary Compound 21), 883.7 parts by mass of methyl ethyl ketone, and 29.3 parts by mass of cyclohexanone were added and stirred. The mixture was filtered through a PTFE filter having a pore diameter of 0.45 μm to prepare a coating solution for low refractive index layer (LL-64). The viscosity of the coating solution was 0.49 [mPa · sec], the surface tension was 24 [mN / m], and the amount of the coating solution applied to the transparent support was 5.0 [ml / m ² ]. .

(Preparation of coating solution for low refractive index layer (LL-65))
71.1 parts by mass of a solution obtained by dissolving the above fluorinated copolymer in methyl ethyl ketone so as to have a concentration of 23.7% by mass, a terminal methacrylate group-containing silicone resin X-22-164C (manufactured by Shin-Etsu Chemical Co., Ltd.) 0 0.5 parts by mass, 0.8 parts by mass of a photo radical generator (Exemplary Compound 21), 898.1 parts by mass of methyl ethyl ketone, and 29.5 parts by mass of cyclohexanone were added and stirred. The mixture was filtered through a PTFE filter having a pore diameter of 0.45 μm to prepare a coating solution for low refractive index layer (LL-65). The viscosity of the coating solution was 0.46 [mPa · sec], the surface tension was 24 [mN / m], and the amount of the coating solution applied to the transparent support was 6.0 [ml / m ² ]. .
The surface condition when the coating solution for the low refractive index layer was changed to LL-61 to LL-65 was evaluated. The results are shown in Table 54. When the amount of the coating solution applied to the transparent support is 2 ml / m ² or more, it is possible to apply the coating solution, but at 1.5 ml / m ² , the entire surface cannot be applied uniformly and an antireflection film is created. I couldn't. In addition, when the amount of the coating solution to be applied to the transparent support is 6 ml / m ² , the coating is possible, but since the amount of the coating solution is large, drying is not in time, and vertical streaky unevenness caused by the wind. Occurred on the entire surface.

[Evaluation of antireflection film]
The surface state of the obtained antireflection film was evaluated. Further, the average reflectance was measured in the same manner as in Example E-1.
(Surface shape)
The back surface of the film 1 m ² after coating all the layers was black-coated with magic ink, and then the uniformity of the density of the coated surface was visually evaluated.
○: Contrast difference is inconspicuous ×: Contrast difference is conspicuous The obtained antireflection films (11-1), (11-3) and (11-4) are displayed in the same procedure as in Examples E-9 and 10. When the device was produced, the color unevenness was less than that of the display devices of Examples E-9 and 10 produced by a gravure coater, and the quality was high.

[Example E-12]
Antireflection films (12-1) to (12-5) were produced in the same manner as the antireflection film (11-1) except that the downstream lip land length I _L0 was 10 μm, 30 μm, 70 μm, 100 μm, and 120 μm. . The results are shown in Table 55. When the length of the downstream lip land is in the range of 30 μm to 100 μm, an antireflection film that does not cause surface failure is obtained. In the antireflection film (12-1), streaky unevenness occurs in the longitudinal direction of the base, and the antireflection film (12-5) cannot form the bead 14a at the same speed as the antireflection film (12-1). Application was impossible. Application was possible by reducing the application speed to half, but streaky irregularities occurred in the longitudinal direction of the base. When a display device was prepared for the antireflection films (12-2) to (12-4) in the same procedure as in Examples E-9 and E-10, the background reflection was very small, and the color of the reflected light was low. A display device with a very high display quality, which is remarkably reduced and in which uniformity within the display surface is ensured, was obtained. On the other hand, when an antireflection film obtained from the antireflection films (12-1) and (12-5) is produced in the same procedure as in Examples E-8 and 9, color unevenness is observed in the display device. It is visually recognized and cannot be said to be high quality.

[Example E-13]
Except that the overcoat length LO of the die coater was set to 0 μm, 30 μm, 70 μm, 120 μm, and 150 μm, coating was performed in the same manner as (11-1), and antireflection films (13-1) to (13-5) were applied. Created. The results are shown in Table 56. When the overbite length is in the range of 30 μm to 120 μm, an antireflection film that does not cause surface defects can be obtained. Application was possible with the antireflection film (13-1), but stepped unevenness was recognized in the base width direction when the surface shape was seen. Further, in the antireflection film (13-5), the bead 14a could not be formed at the same speed as (13-1), and the coating was impossible. Application was possible by reducing the application speed to half, but streaky irregularities occurred in the longitudinal direction of the base. In the antireflection films (13-2) to (13-4), when a display device was prepared in the same procedure as in Examples E-9 and 10, the background reflection was very small and the color of the reflected light was remarkably reduced. Furthermore, a display device with very high display quality in which uniformity within the display surface is ensured was obtained. On the other hand, when a display device is created with the antireflection films (13-1) and (13-5) in the same procedure as in Example E-9, 10, uneven coloring is visually recognized in the display device, and what is high quality? I can not say.

[Example E-14]
(UV / ionizing radiation reaction chamber or front chamber web entrance surface device operation example)
It is preferable that at least a part of the entrance surface of the ionizing radiation reaction chamber or the front chamber is movable so that the joining portion of the joining tape does not get caught, and when the joining portion enters, the gap is widened by the joining thickness. For this purpose, for example, (A) an ionization radiation reaction chamber or an entrance surface of the anterior chamber is moved back and forth in the traveling direction, and the gap moves by moving back and forth when the joint passes, or (B) The entrance surface of the ionizing radiation reaction chamber or the front chamber can be moved in the vertical direction with respect to the web surface, and the gap can be expanded by moving up and down as the joint passes.
FIG. 1 is a schematic view of a production apparatus including an ionizing radiation irradiation chamber and an anterior chamber according to the present invention.
FIG. 2 is a side view showing an example of the apparatus operation on the web entrance surface of the manufacturing apparatus equipped with the ionizing radiation irradiation chamber and the front chamber of the present invention, and shows the mode (A). The apparatus having the configuration of FIG. 2 detects the joining member with a sensor before the joining member joining and connecting the webs enters the front chamber entrance during the web conveyance, and the sensor and the sensor through the control unit (not shown). An air cylinder attached to at least a part of the web entrance surface of the front chamber that operates in conjunction with it allows the entrance surface to move back and forth in the direction of web travel, thereby escaping the thickness of the joining member. It is something that can be done.

3 and 4 are views showing the above-described embodiment (B), FIG. 3 is a view schematically showing the web entrance surface of the front chamber, and FIG. 4 is an operation of the web entrance surface of the front chamber. FIG. A gap between the web and the entrance surface is determined by making a part of the web surface of the front chamber web movable and making contact with both ends of the web with bearing touch rolls. When the joining member passes, the bearing touch roll gets over the joining member, and the gap of the entrance surface is kept constant.
The movable means at the entrance is not limited to the above embodiment as long as it can escape the joint.

It is the schematic diagram which showed the manufacturing apparatus which comprised the ionizing-radiation reaction chamber and the front chamber used in layer formation method (III)-(V). It is the side view which showed an example of operation | movement of the web entrance surface of the manufacturing apparatus which comprised the ionizing radiation reaction chamber used in layer formation method (III)-(V) and the front chamber. It is the figure which showed typically an example of the web entrance surface of the front chamber of the manufacturing apparatus which comprised the ionizing radiation reaction chamber used in layer formation method (III)-(V) and the front chamber. It is the side view which showed typically the operation | movement of the web entrance surface of the front chamber of FIG. It is sectional drawing which shows typically an example of the anti-reflective film which has anti-glare property. It is a schematic diagram which shows an example of a structure of the apparatus for manufacturing the antireflection film of this invention. It is a schematic sectional drawing which shows one Embodiment of the die-coater preferably used in this invention. (A) It is an enlarged view of the die coater of FIG. (B) It is a schematic sectional drawing which shows the conventional slot die. It is a perspective view which shows the slot die of the coating process implemented in manufacture of the antireflection film of this invention, and its periphery. It is sectional drawing which shows typically the relationship between the pressure reduction chamber of FIG. 9, and a web. It is sectional drawing which shows typically the relationship between the pressure reduction chamber of FIG. 9, and a web.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Anti-glare antireflection film 2 Transparent base material 3 Anti-glare layer 4 Low refractive index layer 5 Translucent fine particle W Web 6 Base film roll 7 Winding roll 100,200,300,400 Film-forming unit 101,201 , 301, 401 Coating unit 102, 202, 302, 402 Drying unit 103, 203, 303, 403 Curing device 10 Coater 11 Backup roll 13 Slot die 14 Coating solution 14a Bead shape 14b Coating film 15 Pocket 16 Slot 16a Slot opening 17 Tip lip 18 Land (flat part)
18a Upstream lip land 18b Downstream lip land I _LO Land length of the downstream lip land 18b I _UP Land length of the upstream lip land 18a LO Over bit length _GL Gap between the tip lip 17 and the web W 30 Slot die the gap between the gap G _S side plate 40b and the web W between 31a upstream lip land 31b downstream lip land 32 pocket 33 slot 40 vacuum chamber 40a back plate 40b side plate 40c screws G _B back plate 40a and the web W

Claims (37)

A method for producing an optical film having at least one functional layer on a transparent substrate, wherein at least one layer laminated on the transparent substrate is formed by a layer forming method including the following steps (1) and (2): A method for producing an optical film, comprising: forming an optical film.
(1) A step of coating an application layer on a transparent substrate,
(2) A step of curing the coating layer by irradiating ionizing radiation in an oxygen concentration atmosphere lower than the oxygen concentration in the atmosphere. A method for producing an optical film having at least one functional layer on a transparent substrate, including at least one layer laminated on the transparent substrate, including the following steps (1) to (3): The method for producing an optical film according to claim 1, wherein the method is formed by a layer forming method in which the transporting step (2) and the curing step (3) are continuously performed.
(1) A step of coating an application layer on a transparent substrate,
(2) A step of transporting the film having the coating layer in an oxygen concentration atmosphere lower than the oxygen concentration in the air,
(3) A step of irradiating the film with ionizing radiation in an atmosphere having an oxygen concentration of 3% by volume or less to cure the coating layer. A method for producing an optical film having at least one functional layer on a transparent substrate, including at least one layer laminated on the transparent substrate, including the following steps (1) to (3): The method for producing an optical film according to claim 1, wherein the method is formed by a layer forming method in which the transporting step (2) and the curing step (3) are continuously performed.
(1) A step of coating an application layer on a transparent substrate,
(2) A step of transporting the film having the coating layer in an oxygen concentration atmosphere lower than the oxygen concentration in the air,
(3) A step of curing the coating layer by irradiating the film with ionizing radiation while heating the film so that the film surface temperature is 25 ° C. or higher in an atmosphere having an oxygen concentration of 3% by volume or less. A method for producing an optical film having at least one functional layer on a transparent substrate, including at least one layer laminated on the transparent substrate, including the following steps (1) to (3): The method for producing an optical film according to claim 1, wherein the method is formed by a layer forming method in which the transporting step (2) and the curing step (3) are continuously performed.
(1) A step of coating an application layer on a transparent substrate,
(2) A step of conveying the film having the coating layer in an oxygen concentration atmosphere lower than the oxygen concentration in the atmosphere while heating the film surface temperature to be 25 ° C. or higher,
(3) A step of irradiating the film with ionizing radiation in an atmosphere having an oxygen concentration of 3% by volume or less to cure the coating layer. A method for producing an optical film having at least one functional layer on a transparent substrate, including at least one layer laminated on the transparent substrate, including the following steps (1) to (3): The method for producing an optical film according to claim 1, wherein the method is formed by a layer forming method in which the transporting step (2) and the curing step (3) are continuously performed.
(1) A step of coating an application layer on a transparent substrate,
(2) A step of conveying the film having the coating layer in an oxygen concentration atmosphere lower than the oxygen concentration in the atmosphere while heating the film surface temperature to be 25 ° C. or higher,
(3) A step of curing the coating layer by irradiating the film with ionizing radiation while heating the film so that the film surface temperature is 25 ° C. or higher in an atmosphere having an oxygen concentration of 3% by volume or less.   A method for producing an optical film having at least one functional layer on a transparent substrate, wherein the layer forming method according to any one of claims 1 to 5 is continued to a curing step of the coating layer by ionizing radiation irradiation. And a step of transporting the cured film while heating so that the film surface temperature is 25 ° C. or higher in an atmosphere having an oxygen concentration of 3% by volume or less. A method for producing an optical film having at least one functional layer on a transparent substrate, comprising at least one layer laminated on the transparent substrate, comprising the following steps (1) to (3): (2) and (3) are formed by the layer forming method performed continuously, The manufacturing method of the optical film characterized by the above-mentioned.
(1) A step of coating an application layer on a transparent substrate,
(2) A step of irradiating the film having the coating layer with ionizing radiation in an atmosphere having an oxygen concentration of 3% by volume or less,
(3) A step of maintaining the film after irradiation with ionizing radiation at a film surface temperature of 60 ° C. or less in an atmosphere having an oxygen concentration of 3% by volume or less.   In the manufacturing method of the optical film of Claim 7, Before the process of irradiating ionizing radiation in the atmosphere with the said oxygen concentration of 3 volume% or less, oxygen concentration is 3 volume% or less and more than the oxygen concentration at the time of an ionizing radiation irradiation process The manufacturing method of the optical film characterized by having the process conveyed in the atmosphere of this.   The temperature difference between the film surface temperature in the step of irradiating the ionizing radiation and the film surface temperature in the step of maintaining the film surface temperature at 60 ° C. or lower in an atmosphere having an oxygen concentration of 3% by volume or lower that is continuous with this step is 20 The method for producing an optical film according to claim 7 or 8, wherein the method is within a temperature range. A method for producing an optical film having at least one functional layer on a transparent substrate, wherein at least one layer laminated on the transparent support comprises the following steps (1) and (2): The manufacturing method of the optical film characterized by forming by these.
(1) A step of applying and drying a coating liquid containing an ionizing radiation curable compound on a web containing a transparent substrate that continuously runs, and forming a coating layer;
(2) The coating layer on the web is irradiated with ionizing radiation in an atmosphere having an oxygen concentration of 3% by volume or less, and an atmosphere having an oxygen concentration of 3% by volume or less for 0.5 seconds or longer from the start of ionizing radiation irradiation. Maintaining the web underneath and curing the coating layer. A method for producing an optical film having at least one functional layer on a transparent substrate, comprising at least one layer laminated on a transparent support, comprising the following steps (1) to (3): A method for producing an optical film, characterized in that the optical film is formed by a layer forming method in which steps (2) and (3) are continuously performed.
(1) A step of applying and drying a coating liquid containing an ionizing radiation curable compound on a web containing a transparent substrate that continuously runs, and forming a coating layer;
(2) a step of spraying an inert gas directly on the surface of the coating layer on the web;
(3) The coating layer on the web is irradiated with ionizing radiation in an atmosphere having an oxygen concentration of 3% by volume or less, and an atmosphere having an oxygen concentration of 3% by volume or less for 0.5 seconds or longer from the start of ionizing radiation irradiation. Maintaining the web underneath and curing the coating layer. A method for producing an optical film having at least one functional layer on a transparent substrate, wherein at least one layer laminated on the transparent support comprises the following steps (1) and (2): The manufacturing method of the optical film characterized by the above-mentioned.
(1) A step of applying and drying a coating liquid containing an ionizing radiation curable compound on a web containing a transparent substrate that continuously runs, and forming a coating layer;
(2) The coating layer on the web is irradiated with ionizing radiation in an atmosphere having an oxygen concentration of 3% by volume or less, and an oxygen concentration of 3 volume is maintained until the polymerization reaction of the ionizing radiation curable compound is completed by 50% or more. % Maintaining the web under an atmosphere of less than or equal to% and curing the coating layer. A method for producing an optical film having at least one functional layer on a transparent substrate, comprising at least one layer laminated on a transparent support, comprising the following steps (1) to (3): A method for producing an optical film, characterized in that the optical film is formed by a layer forming method in which steps (2) and (3) are continuously performed.
(1) A step of applying and drying a coating liquid containing an ionizing radiation curable compound on a web containing a transparent substrate that continuously runs, and forming a coating layer;
(2) a step of spraying an inert gas directly on the surface of the coating layer on the web;
(3) The coating layer on the web is irradiated with ionizing radiation in an atmosphere having an oxygen concentration of 3% by volume or less, and the oxygen concentration of 3 volume is maintained until the polymerization reaction of the ionizing radiation curable compound is completed by 50% or more. % Maintaining the web under an atmosphere of less than or equal to% and curing the coating layer.   In the curing step of the coating layer, the ionizing radiation is irradiated to the coating layer on the web a plurality of times in an atmosphere having an oxygen concentration of 3% by volume or less, and at least two of these ionizing radiation irradiations are continuously performed. The method for producing an optical film according to claim 10, wherein the method is performed in an ionizing radiation reaction chamber of 3% by volume or less.   The method for producing an optical film according to any one of claims 10 to 14, wherein the curing step is performed while heating so that the coating layer surface temperature on the web is 60 ° C or higher. Method.   16. The method for producing an optical film according to claim 10, wherein the web having the continuously running coating layer is passed through a front chamber made of an inert gas injected into a low oxygen concentration, and further the web. Is carried into an ionizing radiation reaction chamber having an oxygen concentration of 3% by volume or less injected with an inert gas installed continuously with the anterior chamber, and the coating layer is cured in the ionizing radiation reaction chamber. A method for producing an optical film.   The method for producing an optical film according to claim 16, wherein the inert gas injected into the ionizing radiation reaction chamber is blown out from at least a web entrance side of the ionizing radiation reaction chamber. Production method.   The gap with the coating layer surface on the web is 0.2 to 15 mm in at least one of the surfaces constituting the web entrance side of the ionizing radiation reaction chamber and the front chamber according to claim 16 or 17. The manufacturing method of the optical film of description.   In at least one of the surfaces constituting the web entrance side of the ionizing radiation reaction chamber and the front chamber, at least a part of the surface constituting the web entrance side is movable, and when passing through the joining member joining the web, at least The method for producing an optical film according to any one of claims 16 to 18, wherein the thickness of the joining member escapes. A method for continuously producing an optical film having at least one functional layer on a transparent substrate in a web state, wherein at least one of the layers laminated on the transparent support is the following (1) and (2) A method for producing an optical film, characterized in that the optical film is formed by a layer forming method comprising the steps of:
(1) A step of applying and drying a coating solution containing at least one oxime-based polymerization initiator on a transparent web substrate to form a coating layer, (2) a coating layer on the transparent web substrate, Irradiating ionizing radiation in an atmosphere having an oxygen concentration of 3% by volume or less, and maintaining the transparent web substrate in an atmosphere having an oxygen concentration of 3% by volume or less for 0.5 seconds or more from the start of ionizing radiation irradiation, A step of curing the coating layer. A method for continuously producing an optical film having at least one functional layer on a transparent substrate in a web state, wherein at least one of the layers laminated on the transparent support is the following (1) and (2) A method for producing an optical film, characterized in that the optical film is formed by a layer forming method comprising the steps of:
(1) A step of applying and drying a coating liquid containing at least one oxime polymerization initiator on a transparent web substrate to form a coating layer;
(2) Irradiating the coating layer on the transparent web substrate with ionizing radiation while heating so that the film surface temperature is 60 ° C. or higher in an atmosphere having an oxygen concentration of 3% by volume or less, and starting irradiation with ionizing radiation For 0.5 second or more, and maintaining the transparent web substrate in an atmosphere having an oxygen concentration of 3% by volume or less to cure the coating layer.   The optical film manufacturing method according to claim 20 or 21, wherein the web having the continuously running coating layer is passed through an anterior chamber in which an inert gas is injected to obtain a low oxygen concentration, and the web is further passed through the web. An optical system characterized in that it is carried into an ionizing radiation reaction chamber having an oxygen concentration of 3% by volume or less injected with an inert gas installed continuously with the front chamber, and the coating layer is cured in the ionizing radiation reaction chamber. A method for producing a film.   The method for producing an optical film according to claim 1, wherein the ionizing radiation is ultraviolet light. The method for producing the optical film has a step of applying a coating liquid from the slot of the tip lip by bringing the land of the tip lip of the slot die close to the surface of the web that is continuously supported by a backup roll, and
When the coating liquid has a land length in the web traveling direction of the tip lip on the web traveling direction side of the slot die of 30 μm or more and 100 μm or less, and the slot die is set at the coating position, the traveling direction of the web The gap between the tip lip on the opposite side of the web and the web is applied using a coating apparatus installed so that the gap between the tip lip on the web traveling direction side and the web is 30 μm or more and 120 μm or less. The method for producing an optical film according to claim 1. The viscosity at the time of application | coating of the said coating liquid is 2.0 [mPa * sec] or less, and the quantity of the coating liquid apply | coated to the web surface is 2.0-5.0 [ml / m < ² >]. The method for producing an optical film according to claim 24.   The method for producing an optical film according to claim 24 or 25, wherein the coating liquid is applied to a continuously running web surface at a speed of 25 [m / min] or more.   An optical film produced by the method according to claim 1.   A manufacturing apparatus for producing an optical film having at least one functional layer on a transparent substrate, comprising an ionizing radiation reaction chamber in which ionizing radiation irradiation is performed, and a front chamber in front of the ionizing radiation reaction chamber, and The ionizing radiation reaction chamber and the front chamber each have a web entrance for carrying a web containing a transparent base material having a coating layer and continuously running, wherein the ionizing radiation reaction chamber and the front chamber are An optical film that is maintained at a low oxygen concentration by being injected with an inert gas and that the inert gas injected into the ionizing radiation reaction chamber is blown out from the web entrance of the ionizing radiation reaction chamber. Manufacturing equipment.   The gap with the surface of the coating layer formed on the web is 0.2 to 15 mm in at least one of the surfaces constituting the web entrance side of the ionizing radiation reaction chamber and the front chamber. 28. An optical film manufacturing apparatus according to 28.   In at least one of the surfaces constituting the web entrance side of the ionizing radiation reaction chamber and the front chamber, at least a part of the surface constituting the web entrance side is movable, and when passing through the joining member joining the web, at least 30. The apparatus for producing an optical film according to claim 28, wherein the thickness of the joining member is escaped.   An antireflection film produced by the method according to claim 1.   The antireflection film according to any one of claims 1 to 27, wherein the functional layer has a low refractive index layer having a thickness of 200 nm or less, and the low refractive index layer is formed by the layer forming method. .   The antireflective film according to claim 32, wherein the low refractive index layer constituting the antireflective film contains a fluorine-containing polymer. 34. The antireflection film according to claim 33, wherein the fluoropolymer is a fluoropolymer represented by the following general formula 1.

[In General Formula 1, L represents a linking group having 1 to 10 carbon atoms, and m represents 0 or 1. X represents a hydrogen atom or a methyl group. A represents a polymerization unit of any vinyl monomer, and may be a single component or a plurality of components. x, y, and z represent mol% of each constituent component, and represent values satisfying 30 ≦ x ≦ 60, 5 ≦ y ≦ 70, and 0 ≦ z ≦ 65. ]   The antireflection film according to any one of claims 32 to 34, wherein the low refractive index layer contains hollow silica fine particles.   It is a polarizing plate which has a polarizing film and the protective film laminated | stacked on both surfaces, Comprising: The antireflection film in any one of Claims 31-35 is provided in at least one of these two protective films. A polarizing plate characterized by being used.   An image display device comprising the antireflection film according to any one of claims 31 to 35 or the polarizing plate according to claim 36 on an outermost surface of the display.

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