JP5309677B2 - Method for producing hard coat film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing a hard coating film having high hardness and sufficient resistance to curling of a cured coat while preventing blocking failure and to provide a hard coating film produced by the production method, a polarizing plate using the same, and a display unit. <P>SOLUTION: The method for producing a hard coating film comprises coating a transparent film substrate with a hard coating layer-forming material so as to produce a hard coating film, wherein the hard coating layer-forming material contains at least one type of multifunctional acrylate and the coating steps comprise at least the steps of coating, drying, irradiating, and heating at 40&deg;C or higher after irradiation. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to a method for producing a hard coat film, a hard coat film produced by the production method, a polarizing plate using the same, and a display device.

  Plastics are used in various fields for reasons such as good processability, light weight, and low cost. However, the processability is good, but there are drawbacks such as softness and easy scratching on the surface. In order to improve this drawback, it is common to coat a hard coat material and provide a protective layer on the surface. As this hard coat material, the active energy ray-curable resin composition is used because it has advantages such as (1) being fast curable and (2) having low energy cost.

  In recent years, display bodies such as a liquid crystal display, a plasma display, and a touch panel display provided with a film having a hard coat material as a protective layer on the surface thereof are rapidly spreading. In particular, liquid crystal displays have become larger and are used by an unspecified number of consumers, so hard coat materials used for them have higher hardness, scratch resistance, and curling of the film when cured. It is requested. For this reason, in order to require higher hardness and scratch resistance and to improve workability, there is also a demand for an active energy ray-curable resin composition in which the curl of the cured film is small. The following techniques are disclosed with respect to the said subject. Norbornane diisocyanate, acrylate having at least one hydroxyl group selected from the group consisting of pentaerythritol tri (meth) acrylate, dipentaerythritol penta (meth) acrylate and bis (2- (meth) acryloyloxyethyl) hydroxyethyl isocyanurate Acrylate (A) which is an addition reaction product with glycidyl (meth) acrylate having a polyfunctional acrylate (B) having 3 or more (meth) acryloyl groups in one molecule and / or an epoxy group in the side chain A hard coat material using an actinic ray curable resin composition for a film protective layer containing a polymer (C) having a (meth) acryloyl group obtained by reacting an α, β-unsaturated carboxylic acid with a polymer is disclosed. (For example, refer to Patent Document 1). This blends norbornane diisocyanate, a specific acrylate resin having a hydroxyl group, and the like, thereby achieving high hardness, scratch resistance, and curling of the cured film.

  The hard coat film is provided with a hard coat layer on at least one surface of a transparent film substrate, and the hard coat layer is formed of two urethane acrylates, polyol (meth) acrylates and hydroxyl groups. A hard coat film including a (meth) acrylic polymer having an alkyl group as described above is disclosed (for example, see Patent Document 2). Similar to Patent Document 1, high hardness and curling of the cured film are suppressed by blending a specific acrylate resin and acrylic polymer.

However, in the above-described technique or the like, when high hardness is to be obtained, it is necessary to increase the irradiation amount of active energy rays, so that suppression of curing shrinkage cannot be obtained, and curling of the cured coating is not sufficiently suppressed. Moreover, since materials, such as a specific acrylate resin, are used, it leads also to high cost. Also, for example, when a hard coat layer and a surface on which a hard coat layer is not formed are overlapped in a state where a high temperature and high humidity period such as summer is assumed, or the hard coat film is wound in a roll shape. When stored in the removed state, problems such as sticking to each other (blocking) and scratches on the hard coat layer surface occur, and reflection is applied by applying an antireflection layer on the blocked hard coat layer. When the prevention film is formed, there is a problem that a uniform surface cannot be obtained and the skin is distorted. These have led to a decline in product value and productivity, and an immediate solution has been desired.
JP 2007-131837 A JP 2007-46031 A

  Accordingly, an object of the present invention is to provide a method for producing a hard coat film having high hardness, sufficient curl resistance of a cured film, and further preventing blocking failure. Furthermore, it is providing the hard coat film manufactured by this manufacturing method, a polarizing plate using the same, and a display apparatus.

  The above object of the present invention is achieved by the following configurations.

1. In a method for producing a hard coat film in which a hard coat layer forming material is coated on a transparent film substrate to produce a hard coat film, the hard coat layer forming material contains at least one polyfunctional acrylate, and a coating step but at least the coating, drying, irradiation, and Ri Do the step of the heat treatment by light irradiation after 60 ° C. or more, the step of the heat treatment is intended to take place after being wound into a roll after the light irradiation There, the production method of the hard coat film heating temperature in the step of the heat treatment, characterized in Rukoto temperature is raised at 0.3 to 5 ° C. / hour.

2 . 2. The method for producing a hard coat film as described in 1 above, wherein the heat treatment step is a heat treatment at 80 ° C. or higher.

3 . 3. The method for producing a hard coat film as described in 2 above, wherein the heat treatment step is a heat treatment at 120 ° C. or higher.

4 . The method for producing a hard coat film according to any one of the above items 1 to 3 , wherein the heating temperature in the heat treatment step is lowered at a rate of 0.3 to 5 ° C / hour.

5 . The said transparent film base material is a cellulose-ester film, The manufacturing method of the hard coat film of any one of said 1-4 characterized by the above-mentioned.

6 . 6. The method for producing a hard coat film as described in 5 above, wherein the cellulose ester film is produced by a melt casting method.

  According to the present invention, it is possible to provide a method for producing a hard coat film having high hardness, sufficient curl resistance of a cured film, and further preventing blocking failure. Furthermore, the hard coat film manufactured by this manufacturing method, the polarizing plate using the same, and a display apparatus can be provided.

  The best mode for carrying out the present invention will be described in detail below, but the present invention is not limited thereto.

  The method for producing a hard coat film of the present invention is a production method for producing a hard coat film by coating a hard coat layer forming material on a transparent film substrate, wherein the hard coat layer forming material is at least one multifunctional acrylate. And the coating step comprises at least coating, drying, light irradiation, and heat treatment at 40 ° C. or higher after light irradiation (hereinafter also referred to as aging treatment in the present invention).

  Japanese Patent Application Laid-Open No. 2006-145737 discloses an antiglare antireflection film characterized by subjecting a hard coat layer to a surface treatment followed by an aging treatment and then a low refractive index layer. The purpose of this patent is to perform an aging treatment after the surface treatment of the hard coat layer in order to uniformly and uniformly apply the low refractive index layer on the upper layer of the hard coat layer.

  Japanese Patent Application Laid-Open No. 2007-3766 has a step of coating a functional thin film by continuously conveying the long film in a method for producing an optical film in which a functional thin film is provided on a long film, After the coating, a method for producing an optical film is disclosed in which the optical film is wound up in a roll shape at a temperature of 50 ° C. or higher and subsequently subjected to a heat treatment at 50 ° C. or higher for one day or longer. This patent is a technique for producing a uniform optical film without color unevenness by heat-treating the antireflection layer, which is a functional thin film, at 50 ° C. or higher. Both of the two patent documents are techniques related to the coating on the hard coat layer of the low refractive index layer or the antireflection layer, but by heat treatment after the light irradiation of the present invention, the hardness is high, There is no description about the effect of having a sufficient cured film curl resistance and increasing the blocking resistance of the hard coat layer, and it was surprising that it cannot be predicted from the conventional knowledge.

  Hereinafter, the present invention will be described in detail.

<< Heat treatment process >>
In the present invention, the heat treatment step includes, for example, a form in which the heat treatment is subsequently performed after coating, drying, and light irradiation as shown in FIG. In addition, after coating, drying, and light irradiation as shown in FIG. 2, the roll of the wound hard coat film is placed on a movable carriage and moved, and in the heat treatment chamber shown by A in FIG. The form processed by time is mentioned. Alternatively, after the heat treatment in FIG. 1, a form in which the heat treatment is performed in the heat treatment chamber illustrated in FIG. In addition, the heat treatment step needs to be performed in a place where the temperature and humidity can be adjusted in order to stably perform the heat treatment, and is preferably performed in a heat treatment chamber such as a clean room free from dust.

  A preferable temperature for the heat treatment is 40 ° C. or higher, more preferably 60 ° C. or higher, more preferably 80 ° C. or higher, and particularly preferably 120 ° C. or higher. Further, the upper limit temperature is appropriately set from the characteristics of the base film. For example, in the case of the form as shown in FIG. 1, the heat treatment is preferably performed at 45 ° C. or higher for 30 seconds to 10 minutes, more preferably at 70 ° C. or higher for 30 seconds to 10 minutes. Is preferred. In the case of a form like FIG. 2, it is preferable to carry out for 1 hour-30 days in the temperature range of 50 to 140 degreeC. Furthermore, it is more preferable to carry out at 60 ° C. to 140 ° C. for 1 hour to 30 days. The effect is not changed for 30 days or more, and preferably within 30 days. The heat treatment time in the present invention refers to a time during which the atmosphere temperature of the heat zone or the heat treatment chamber is kept constant at a desired temperature, and does not include the time for temperature rise and time for temperature drop. To do.

  The temperature to be held is preferably in the range of ± 5 ° C. of the set temperature. There may be a plurality of heat treatment chambers A. In that case, it may be designed so that each temperature can be changed. In order to increase the temperature difference between the inside and outside of the roll of the optical film roll when the temperature rises rapidly in the heating zone and the heat treatment chamber, it is preferable to gradually raise or lower the temperature. It is particularly preferable that the temperature is 3 to 5 ° C./hour because the object and effects of the present invention are easily exhibited.

  FIG. 1 is a schematic view showing a step of performing heat treatment continuously after irradiation with actinic rays according to the present invention.

  The long film Y is fed out from the feed roll 1, transported by the transport roller 2, and a hard coat layer is applied by the extrusion coater 3. At this time, the hard coat layer may be a single layer structure or a plurality of layers. Next, the long film Y coated with the hard coat layer is dried in the drying zone 5. The temperature of the drying zone 5 is preferably 50 to 150 ° C. Drying is performed by blowing warm air whose temperature and humidity are controlled from the front surface, back surface, or both surfaces of the long film Y. After drying, the thin film is cured by irradiating with actinic rays such as ultraviolet rays by an air-cooled actinic ray lamp 6a in the actinic ray irradiation lamp unit 6. Alternatively, the half-cure state can be achieved by controlling the irradiation amount and irradiation conditions. Actinic ray irradiation can also be performed in a state in which the long film Y is wound around the opposing roll 4 whose temperature is controlled to 20 to 120 ° C. in advance.

At that time, it is also preferable to send cooling air from the air cooling air ventilation port 6b to adjust the temperature of the actinic ray irradiation section, and to supply N2 gas from the N2 supply chamber in order to promote hardening of the hard coat layer. Is also preferable. As an example of the actinic ray lamp, a low pressure mercury lamp, a medium pressure mercury lamp, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a carbon arc lamp, a metal halide lamp, a xenon lamp, or the like can be used. These light sources are preferably air-cooled or water-cooled. The irradiation conditions vary depending on individual lamps, the dose of active ray is preferably a ^{50mJ / cm 2 ~1J / cm 2} , particularly preferably 50 to 500 mJ / cm ^2. Further, it is preferable to reduce the oxygen concentration to 0.01% to 5% by nitrogen purge in the irradiated portion.

  Subsequently, after irradiating actinic light, it heat-processes in the heating zone 7. In the heating zone 7, the long film Y is heated at a predetermined temperature for a predetermined time by the transport rollers 2 arranged above and below.

  When the heat treatment is performed, it is preferably performed while applying a tension in the film transport direction or the width direction, and the applied tension is preferably 50 to 500 N / m, and more preferably 250 to 500 N / m. In the range of 250 to 500 N / m, the object effect of the present invention is more effectively exhibited. When it exceeds 500 N / m, it becomes difficult to maintain the flatness of the film.

  The width tension applying method is not particularly limited, and may be a free span, a back roll or the like. In addition, a method of applying tension in the width direction using a width regulating device (tenter) is also effective, preferably stretching at 3.0% or less, more preferably 0.05% to 1.0%. This is more effective. Thereby, a film excellent in blocking resistance can be obtained.

  The long film Y subjected to the heat treatment is taken up as a take-up roll 9 in the take-up chamber 8. In that case, it is also preferable to carry out while blowing hot air of a predetermined temperature from the hot air outlet 10. As a measure for preventing electrification and dust adhesion, the hot air is preferably adjusted to a relative humidity in the range of 10 to 70% RH, preferably 20 to 70% RH, particularly 40 to 60% RH. Moreover, it is preferable that warm air is an ion wind, and it is preferable to install a static elimination apparatus and an air cleaner in the vicinity of the winding part.

  FIG. 2 is a schematic view in which after the coating, drying, and light irradiation according to the present invention, the wound hard coat film roll is placed on a movable carriage 12 and heat-treated in the heat treatment chamber A.

  In the heat treatment, the hard coat film roll wound on the movable carriage 12 is moved, and the heat treatment is performed in the heat treatment chamber A at a necessary temperature and a required number of days. The heat treatment chamber A is designed so that the temperature can be appropriately changed, and a rapid temperature increase increases the temperature difference between the inside and outside of the winding of the hard coat film roll, so that the temperature can be gradually increased or decreased. It is preferably designed to be able to do so. That is, it is preferable that the rate of temperature rise or the rate of temperature fall is 0.3 to 5 ° C./hour because the object and effects of the present invention are easily exhibited.

  If the rate of temperature increase during the heat treatment is too fast, the film suddenly expands and wrinkles or the like are liable to enter the vicinity of the core. Moreover, if it is slow, productivity will be inferior and it is not realistic. There is no particular limitation on the temperature rising pattern, and a linear, curvilinear or stepwise pattern may be taken for optimization. Further, there may be a temporary temperature drop during the temperature rising period.

  In addition, the hard coat film according to the present invention is preferably subjected to knurling in order to prevent blocking or to maintain a good winding shape. The knurling process should just be formed in the at least one surface of the film, and may be formed in both surfaces. The thickness of the knurling part is preferably larger than the film thickness of the hard coat layer, and the thickness of the knurling part is preferably in the range of 5 to 30 μm. Preferably it is the range of 10-25 micrometers.

  When winding the hard coat film into a roll, the wound core may be of any material as long as it is a cylindrical core, preferably a hollow plastic core, Any heat-resistant plastic that can withstand the heat treatment temperature may be used, and examples thereof include phenol resins, xylene resins, melamine resins, polyester resins, and epoxy resins. A thermosetting resin reinforced with a filler such as glass fiber is preferred. The number of windings on these winding cores is preferably 100 windings or more, more preferably 500 windings or more, and the winding thickness is preferably 5 cm or more.

  When the heat treatment is performed in a state where the roll having the long-winding hard coat film wound around the plastic core is wound, the roll is preferably rotated, and the rotation is performed once per minute. The following speeds are preferred, and may be continuous or intermittent. Moreover, it is also preferable to perform the roll rewinding once or more during the heating period.

  In order to rotate the long hard coat film wound around the core during the heat treatment, it is preferable to provide a dedicated turntable in the heat treatment chamber. More preferably, the hard coat film is set on a dedicated carriage having a heat-resistant rotation function and rotated during the heat treatment in the heating chamber.

  It is also preferable that the hard coat film roll after the heat treatment is carried, for example, to a rewinding step (not shown) and cooled to room temperature while the hard coat film is rewinded to obtain a rewind roll. Further, in the rewinding step, it is preferable to pass through an atmosphere having a relative humidity of 10 to 70% RH or to wind in the atmosphere. When the relative humidity is preferably 20 to 70% RH, particularly 40 to 60% RH, a good hard coat film roll can be obtained without static electricity failure or collapse of the winding shape. The film rewinding speed is 1 to 200 m / min, preferably 10 to 100 m / min. At the time of rewinding, it is preferable that the film is drawn out and brought into contact with at least one roller in order to lower the film temperature.

  When rotating or rewinding these rolls, there is a possibility that static electricity failure or scratches may occur on the film. It is preferable to install a static eliminator or in a clean room. The surface of the contact roller during rewinding is smooth. It is preferable to use one having a high value.

  As the heating means, hot air blowing, contact heat transfer using a heating roll, induction heating using a microwave, radiant heat heating using an infrared heater, or the like can be used. As the infrared heater, an electric, gas, oil or steam far infrared ceramic heater can be used. A commercially available infrared heater (for example, manufactured by Noritake Company Limited) may be used. An oil-type or steam-type infrared heater using oil or steam as the heat medium is preferable from the viewpoint of explosion prevention in an atmosphere in which an organic solvent coexists.

  Moreover, the film temperature and heating temperature at the time of a heating can be measured with the non-contact-type infrared thermometer generally marketed. Further, feedback control may be performed on the heating means in order to control the temperature range.

《Hard coat layer》
The hard coat layer according to the present invention will be described.

  The hard coat layer according to the present invention is provided on at least one surface of the transparent film substrate. In the present invention, it is preferable to perform a heat treatment after forming the hard coat layer, and further provide a functional layer such as an antireflection layer (high refractive index layer, low refractive index layer, etc.) thereon.

  In addition, the hard coat film in this invention means the film whose pencil hardness is H-8H. Most preferably, it is 2H-6H. The pencil hardness is evaluated by pencil hardness evaluation specified by JIS K 5400 using a test pencil specified by JIS S 6006 after the prepared hard coat film is conditioned at a temperature of 25 ° C. and a relative humidity of 60% for 2 hours. It is the value measured according to the method.

(Polyfunctional acrylate)
In general, an actinic ray curable resin such as ultraviolet rays is used as the hard coat layer composition, and the present invention is characterized by containing a polyfunctional acrylate as such an actinic ray curable resin. The polyfunctional acrylate is preferably selected from the group consisting of pentaerythritol polyfunctional acrylate, dipentaerythritol polyfunctional acrylate, pentaerythritol polyfunctional methacrylate, and dipentaerythritol polyfunctional methacrylate. Here, the polyfunctional acrylate is a compound having two or more acryloyloxy groups and / or methacryloyloxy groups in the molecule.

  Examples of the polyfunctional acrylate monomer include ethylene glycol diacrylate, diethylene glycol diacrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, trimethylolpropane triacrylate, trimethylolethane triacrylate, and tetramethylolmethane triacrylate. , Tetramethylolmethane tetraacrylate, pentaglycerol triacrylate, pentaerythritol diacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, glycerol triacrylate, dipentaerythritol triacrylate, dipentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, dipentaerythritol Lithol hexaacrylate, tris (acryloyloxyethyl) isocyanurate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, 1,6-hexanediol dimethacrylate, neopentyl glycol dimethacrylate, trimethylolpropane trimethacrylate, trimethylolethane trimethacrylate, Tetramethylol methane trimethacrylate, tetramethylol methane tetramethacrylate, pentaglycerol trimethacrylate, pentaerythritol dimethacrylate, pentaerythritol trimethacrylate, pentaerythritol tetramethacrylate, glycerol trimethacrylate, dipentaerythritol trimethacrylate, dipentaerythritol tetramethacrylate Acrylate, dipentaerythritol penta methacrylate, dipentaerythritol hexa methacrylate, isobornyl acrylate and the like preferably. These compounds are used alone or in admixture of two or more. Moreover, oligomers, such as a dimer and a trimer of the said monomer, may be sufficient.

  The addition amount of the actinic ray curable resin is preferably 15% by mass or more and less than 70% by mass in the solid content in the hard coat composition.

  In order to accelerate the curing of the actinic ray curable resin, a photopolymerization initiator and an acrylic compound having at least two polymerizable unsaturated bonds in the molecule are contained in a mass ratio of 20: 100 to 0.01: 100. It is preferable.

  Specific examples of the photopolymerization initiator include acetophenone, benzophenone, hydroxybenzophenone, Michler's ketone, α-amyloxime ester, thioxanthone, and derivatives thereof, but are not particularly limited thereto.

In the hard coat layer according to the present invention, a binder such as a known thermoplastic resin, thermosetting resin, or hydrophilic resin such as gelatin can be mixed with the actinic ray curable resin. These resins preferably have a polar group in the molecule. Examples of the polar _{group, -COOM, -OH, -NR 2,} -NR 3 X, -SO 3 M, -OSO 3 M, -PO 3 M 2, -OPO 3 M ( wherein, M represents a hydrogen atom, an alkali A metal or an ammonium group, X represents an acid forming an amine salt, R represents a hydrogen atom or an alkyl group).

  Commercially available actinic radiation curable resins that can be used in the present invention include ADEKA OPTMER KR / BY series: KR-400, KR-410, KR-550, KR-566, KR-567, BY-320B (Asahi) Manufactured by Denka Co., Ltd.); Koei Hard A-101-KK, A-101-WS, C-302, C-401-N, C-501, M-101, M-102, T-102, D-102 NS-101, FT-102Q8, MAG-1-P20, AG-106, M-101-C (manufactured by Guangei Chemical Co., Ltd.); Seika Beam PHC2210 (S), PHC X-9 (K-3), PHC2213 , DP-10, DP-20, DP-30, P1000, P1100, P1200, P1300, P1400, P1500, P1600, SCR900 (Daiichi Seikagaku Corporation KRM7033, KRM7039, KRM7130, KRM7131, UVECRYL29201, UVECRYL29202 (manufactured by Daicel UCB); RC-5015, RC-5016, RC-5020, RC-5031, RC-5100, RC-5102, RC -5120, RC-5122, RC-5152, RC-5171, RC-5180, RC-5181 (Dainippon Ink Chemical Co., Ltd.); 340 clear (manufactured by China Paint Co., Ltd.); Sunrad H-601, RC-750, RC-700, RC-600, RC-500, RC-611, RC-612 (manufactured by Sanyo Chemical Industries); SP -1509, SP-1507 (manufactured by Showa Polymer Co., Ltd.); RCC-15C (manufactured by Grace Japan Co., Ltd.), Aronix M-6100, M-8030, M-8060 (manufactured by Toagosei Co., Ltd.); B420 (manufactured by Shin-Nakamura Chemical Co., Ltd.) or the like can be appropriately selected and used.

  Further, the hard coat layer may contain fine particles of an inorganic compound or an organic compound in order to adjust the scratch resistance, slipperiness and refractive index.

  Examples of inorganic fine particles used in the hard coat layer include silicon oxide, titanium oxide, aluminum oxide, tin oxide, indium oxide, ITO, zinc oxide, zirconium oxide, magnesium oxide, calcium carbonate, calcium carbonate, talc, clay, and calcined kaolin. And calcined calcium silicate, hydrated calcium silicate, aluminum silicate, magnesium silicate and calcium phosphate. In particular, silicon oxide, titanium oxide, aluminum oxide, zirconium oxide, magnesium oxide and the like are preferably used.

  Organic particles include polymethacrylic acid methyl acrylate resin powder, acrylic styrene resin powder, polymethyl methacrylate resin powder, silicon resin powder, polystyrene resin powder, polycarbonate resin powder, benzoguanamine resin powder, melamine resin powder. An ultraviolet curable resin composition such as polyolefin resin powder, polyester resin powder, polyamide resin powder, polyimide resin powder, or polyfluoroethylene resin powder can be added. Particularly preferred are cross-linked polystyrene particles (for example, SX-130H, SX-200H, SX-350H manufactured by Soken Chemical), polymethyl methacrylate particles (for example, MX150, MX300 manufactured by Soken Chemical), and fluorine-containing acrylic resin fine particles. The Examples of the fluorine-containing acrylic resin fine particles include commercial products such as FS-701 manufactured by Nippon Paint. Examples of the acrylic particles include Nippon Paint: S-4000, and examples of the acrylic-styrene particles include Nippon Paint: S-1200, MG-251.

  The average particle diameter of these fine particle powders is preferably 0.01 to 5 μm, more preferably 0.1 to 5.0 μm, and particularly preferably 0.1 to 4.0 μm. Moreover, it is preferable to contain 2 or more types of microparticles | fine-particles from which a particle size differs. The proportion of the ultraviolet curable resin composition and the fine particles is desirably blended so as to be 0.1 to 30 parts by mass with respect to 100 parts by mass of the resin composition.

  In order to increase the heat resistance of the hard coat layer, an antioxidant that does not inhibit the photocuring reaction can be selected and used. Examples include hindered phenol derivatives, thiopropionic acid derivatives, phosphite derivatives, and the like. Specifically, for example, 4,4′-thiobis (6-tert-3-methylphenol), 4,4′-butylidenebis (6-tert-butyl-3-methylphenol), 1,3,5-tris (3,5-di-tert-butyl-4-hydroxybenzyl) isocyanurate, 2,4,6-tris (3,5-di-tert-butyl-4-hydroxybenzyl) mesitylene, di-octadecyl-4- Examples thereof include hydroxy-3,5-di-tert-butylbenzyl phosphate.

  These hard coat layers can be coated by a known method such as a gravure coater, a dip coater, a reverse coater, a wire bar coater, a die coater, or an ink jet method. After application, it is heat-dried and UV-cured.

  The hard coat layer coating solution may contain a solvent, or may be appropriately contained and diluted as necessary. Examples of the organic solvent contained in the coating solution include hydrocarbons (toluene, xylene), alcohols (methanol, ethanol, isopropanol, butanol, cyclohexanol), ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone), It can be appropriately selected from esters (methyl acetate, ethyl acetate, methyl lactate), glycol ethers, and other organic solvents, or a mixture thereof can be used. Propylene glycol monoalkyl ether (1 to 4 carbon atoms of the alkyl group) or propylene glycol monoalkyl ether acetate ester (1 to 4 carbon atoms of the alkyl group) is 5% by mass or more, more preferably 5 to 80%. It is preferable to use the organic solvent containing at least mass%.

  The hard coat layer has a center line average roughness (Ra) defined by JIS B 0601 of 0.001 to 0.1 μm, or a fine hard coat layer and Ra is adjusted to 0.1 to 1 μm. An antiglare hard coat layer may also be used. The center line average roughness (Ra) is preferably measured by an optical interference type surface roughness measuring instrument, and can be measured, for example, using a non-contact surface fine shape measuring device WYKO NT-2000 manufactured by WYKO.

  Further, the hard coat layer preferably contains a silicone surfactant or a polyoxyether compound. As the silicone surfactant, polyether-modified silicone is preferable, and specifically, BYK-UV3500, BYK-UV3510, BYK-333, BYK-331, BYK-337 (manufactured by BYK-Chemical Japan), TSF4440, TSF4445, TSF4446, TSF4452, TSF4460 (GE Toshiba Silicone), KF-351, KF-351A, KF-352, KF-353, KF-354, KF-355, KF-615, KF-618, KF-945, KF- 6004 (polyether-modified silicone oil; manufactured by Shin-Etsu Chemical Co., Ltd.), and the like, but are not limited thereto.

  Of the polyoxyether compounds, the polyoxyethylene oleyl ether compound is preferable, and is generally a compound represented by the general formula (α).

Formula (α) C ₁₈ H ₃₅ —O (C ₂ H ₄ O) nH
In the formula, n represents 2 to 40.

  The average addition number (n) of ethylene oxide with respect to the oleyl part is 2 to 40, preferably 2 to 10, more preferably 2 to 9, and further preferably 2 to 8. The compound of the general formula (α) can be obtained by reacting ethylene oxide with oleyl alcohol.

  Specific products include Emulgen 404 (polyoxyethylene (4) oleyl ether), Emulgen 408 (polyoxyethylene (8) oleyl ether), Emulgen 409P (polyoxyethylene (9) oleyl ether), Emulgen 420 (polyoxy) Ethylene (13) oleyl ether), Emulgen 430 (polyoxyethylene (30) oleyl ether) or more, Kao Corporation, NOFBLEEAO-9905 (polyoxyethylene (5) oleyl ether) manufactured by NOF Corporation.

  Note that () represents the number n. Nonionic polyoxyether compounds may be used alone or in combination of two or more.

  These improve applicability | paintability and it is preferable to add these components in 0.01-3 mass% with respect to the solid content component in a coating liquid.

  Further, the hard coat layer may contain a fluorine-siloxane graft polymer.

  The fluorine-siloxane graft polymer refers to a copolymer polymer obtained by grafting polysiloxane containing siloxane and / or organosiloxane alone and / or organopolysiloxane to at least a fluorine-based resin. Examples of commercially available products include ZX-022H, ZX-007C, ZX-049, and ZX-047-D manufactured by Fuji Kasei Kogyo Co., Ltd. These compounds may be used as a mixture. Fluorine-siloxane graft polymer should be used in a coating solution that has a mass ratio of actinic ray curable resin to fluorine-siloxane graft polymer: energy-active radiation curable resin = 0.05: 100 to 5.00: 100. To preferred.

  The hard coat layer may have a multilayer structure of two or more layers. One of the layers may be a so-called conductive layer containing, for example, conductive fine particles, a π-conjugated conductive polymer, or an ionic polymer. Examples of the π-conjugated conductive polymer include polythiophene, poly (3-methylthiophene), poly (3-ethylthiophene), poly (3-propylthiophene), poly (3-butylthiophene), and poly (3-hexylthiophene). , Poly (3-octylthiophene), poly (3-decylthiophene), poly (3-dodecylthiophene), poly (3-bromothiophene), poly (3-chlorothiophene), poly (3-cyanothiophene), poly (3-phenylthiophene), poly (3,4-dimethylthiophene), poly (3,4-dibutylthiophene), poly (3-hydroxythiophene), poly (3-methoxythiophene), poly (3-ethoxythiophene) , Poly (3-butoxythiophene), poly (3-hexyloxythiophene), poly (3 Octyloxythiophene), poly (3-decyloxythiophene), poly (3-dodecyloxythiophene), poly (3,4-dihydroxythiophene), poly (3,4-dimethoxythiophene), poly (3,4-di Ethoxythiophene), poly (3,4-dipropoxythiophene), poly (3,4-dibutoxythiophene), poly (3,4-dihexyloxythiophene), poly (3,4-dioctyloxythiophene), poly ( 3,4-didecyloxythiophene), poly (3,4-didodecyloxythiophene), poly (3,4-ethylenedioxythiophene), poly (3,4-propylenedioxythiophene), poly (3,4 4-butenedioxythiophene), poly (3-methyl-4-methoxythiophene), poly (3-methyl-4 -Ethoxythiophene), poly (3-carboxythiophene), poly (3-methyl-4-carboxythiophene), poly (3-methyl-4-carboxyethylthiophene), poly (3-methyl-4-carboxybutylthiophene) , Polypyrrole, poly (N-methylpyrrole), poly (3-methylpyrrole), poly (3-ethylpyrrole), poly (3-N-propylpyrrole), poly (3-butylpyrrole), poly (3-octyl) Pyrrole), poly (3-decylpyrrole), poly (3-dodecylpyrrole), poly (3,4-dimethylpyrrole), poly (3,4-dibutylpyrrole), poly (3-carboxypyrrole), poly (3 -Methyl-4-carboxypyrrole), poly (3-methyl-4-carboxyethylpyrrole), poly (3-methyl 4-carboxybutylpyrrole), poly (3-hydroxypyrrole), poly (3-methoxypyrrole), poly (3-ethoxypyrrole), poly (3-butoxypyrrole), poly (3-hexyloxypyrrole), poly ( 3-methyl-4-hexyloxypyrrole), polyaniline, poly (2-methylaniline), poly (3-isobutylaniline), poly (2-anilinesulfonic acid), poly (3-anilinesulfonic acid) and the like. . Each of these may be used alone or two types of copolymers can be suitably used.

  Further, the ionic polymer may contain a color tone adjusting agent (dye or pigment) having a color tone adjusting function as a color correction filter for various display elements, or may contain an electromagnetic wave blocking agent or an infrared absorber. It is preferable to have each function.

  As the coating method of the hard coat layer coating solution, the above-described methods can be used. The coating amount is suitably 0.1 to 40 μm, preferably 0.5 to 30 μm, as the wet film thickness. Moreover, as a dry film thickness, it is an average film thickness of 0.1-30 micrometers, Preferably it is 1-20 micrometers.

  The hard coat layer is preferably irradiated with ultraviolet rays after coating and drying, and the irradiation time for obtaining the necessary amount of active light irradiation is preferably about 0.1 second to 1 minute, and the curing efficiency of the ultraviolet curable resin Or from the viewpoint of work efficiency, 0.1 to 10 seconds is more preferable.

Moreover, it is preferable that the illuminance of these actinic ray irradiation parts is 0.05-0.2 W / m < ² >.

<Antireflection layer>
The hard coat film according to the present invention may be a hard coat film having an antireflection function for external light (hereinafter also referred to as an antireflection film) in which an antireflection layer is coated as an upper layer.

  The antireflection layer is preferably laminated in consideration of the refractive index, the film thickness, the number of layers, the layer order, and the like so that the reflectance is reduced by optical interference. The antireflection layer is preferably composed of a low refractive index layer having a refractive index lower than that of the support, or a combination of a high refractive index layer having a refractive index higher than that of the support and a low refractive index layer. Particularly preferably, it is an antireflection layer composed of three or more refractive index layers, and three layers having different refractive indexes from the support side are divided into medium refractive index layers (high refractive index layers having a higher refractive index than the support). Are preferably laminated in the order of a layer having a lower refractive index) / a high refractive index layer / a low refractive index layer. Alternatively, an antireflection layer having a layer structure of four or more layers in which two or more high refractive index layers and two or more low refractive index layers are alternately laminated is also preferably used.

  Although the following structures can be considered as a layer structure of a film, it is not limited to this.

Film substrate / Hard coat layer Film substrate / Hard coat layer / Medium refractive index layer / Low refractive index layer Film substrate / Hard coat layer / Medium refractive index layer / High refractive index layer / Low refractive index layer Film substrate / Hard base layer / low refractive index layer Film base / hard coat layer / conductive layer Film base / hard coat layer / conductive layer / low refractive index layer Film base / hard coat layer / high refractive index layer (conductive Layer) / low refractive index layer film substrate / hard coat layer / antiglare layer film substrate / hard coat layer / antiglare layer / low refractive index layer film substrate / conductive layer / hard coat layer / low refractive layer Rate layer Back coat layer / film substrate / hard coat layer Back coat layer / film substrate / hard coat layer / antiglare layer Back coat layer / film substrate / hard coat layer / conductive layer Back coat layer / film base Material / C Coating layer / low refractive index layer back coating layer / film substrate / hard coating layer / medium refractive index layer / low refractive index layer back coating layer / film substrate / hard coating layer / antiglare layer back coating layer / film base Material / hard coat layer / antiglare layer / low refractive index layer back coat layer / film substrate / hard coat layer / conductive layer / low refractive index layer back coat layer / film substrate / hard coat layer / high refractive index Layer (conductive layer) / low refractive index layer back coat layer / film substrate / conductive layer / hard coat layer / low refractive index layer [low refractive index layer]
The low refractive index layer preferably contains silica-based fine particles, and the refractive index is lower than the refractive index of the film substrate as a support, and is 1.30 to 1.45 at 23 ° C. and a wavelength of 550 nm. It is preferable that it is the range of these.

  The film thickness of the low refractive index layer is preferably 5 nm to 0.5 μm, more preferably 10 nm to 0.3 μm, and most preferably 30 nm to 0.2 μm.

  The composition for forming a low refractive index layer preferably contains at least one kind of particles having an outer shell layer and porous or hollow inside as silica-based fine particles. In particular, the particles having the outer shell layer and having a porous or hollow interior are preferably hollow silica-based fine particles.

  The composition for forming a low refractive index layer may contain an organosilicon compound represented by the following general formula (OSi-1) or a hydrolyzate thereof, or a polycondensate thereof.

General formula (OSi-1): Si (OR) ₄
In the organic silicon compound represented by the general formula, R represents an alkyl group having 1 to 4 carbon atoms. Specifically, tetramethoxysilane, tetraethoxysilane, tetraisopropoxysilane and the like are preferably used.

  In addition, a silane coupling agent, a curing agent, a surfactant and the like may be added as necessary.

(Hollow silica fine particles)
The hollow silica-based fine particles are (I) composite particles comprising porous particles and a coating layer provided on the surface of the porous particles, or (II) having cavities inside, and the contents are solvent, gas or porous It is a hollow particle filled with a porous material. Note that the low refractive index layer only needs to contain either (I) composite particles or (II) hollow particles, or both.

  Note that the cavity particles are particles having a cavity inside, and the cavity is covered with a coating layer (also referred to as a particle wall). The cavity is filled with contents such as a solvent, a gas, or a porous material used at the time of preparation. It is desirable that the average particle size of such hollow fine particles is in the range of 5 to 300 nm, preferably 10 to 200 nm. The average particle diameter of the hollow fine particles to be used is desirably 3/2 to 1/10, preferably 2/3 to 1/10, of the average film thickness of the low refractive index layer to be formed. These hollow fine particles are preferably used in a state of being dispersed in an appropriate medium in order to form a low refractive index layer. As the dispersion medium, water, alcohol (for example, methanol, ethanol, isopropyl alcohol) and ketone (for example, methyl ethyl ketone, methyl isobutyl ketone), ketone alcohol (for example, diacetone alcohol), or a mixed solvent containing these is preferable.

  The thickness of the coating layer of the composite particles or the thickness of the particle walls of the hollow particles is desirably in the range of 1 to 20 nm, preferably 2 to 15 nm. In the case of composite particles, if the thickness of the coating layer is less than 1 nm, the particles may not be completely covered, and it is easy to use a silicate monomer or oligomer having a low polymerization degree, which is a coating liquid component described later. In some cases, the refractive index of the particles is increased by entering the voids inside the composite particles, and the effect of low refractive index may not be sufficiently obtained. When the thickness of the coating layer exceeds 20 nm, the silicic acid monomer and oligomer do not enter the inside, but the porosity (pore volume) of the composite particles is lowered and the effect of low refractive index is sufficiently obtained. It may not be possible. In the case of hollow particles, if the particle wall thickness is less than 1 nm, the particle shape may not be maintained, and even if the thickness exceeds 20 nm, the effect of low refractive index may not be sufficiently exhibited. .

The coating layer of the composite particles or the particle wall of the hollow particles is preferably composed mainly of silica. Moreover, components other than silica may be contained, and specifically, Al ₂ O ₃ , B ₂ O ₃ , TiO ₂ , ZrO ₂ , SnO ₂ , CeO ₂ , P ₂ O ₃ , Sb ₂ O _3. , MoO ₃ , ZnO ₂ , WO _{3 and the} like. Examples of the porous particles constituting the composite particles include those made of silica, those made of silica and an inorganic compound other than silica, and those made of CaF ₂ , NaF, NaAlF ₆ , MgF, and the like. Among these, porous particles made of a composite oxide of silica and an inorganic compound other than silica are particularly preferable. Examples of inorganic compounds other than silica include Al ₂ O ₃ , B ₂ O ₃ , TiO ₂ , ZrO ₂ , SnO ₂ , CeO ₂ , P ₂ O ₃ , Sb ₂ O ₃ , MoO ₃ , ZnO ₂ and WO _3. 1 type or 2 types or more can be mentioned. In such porous particles, the molar ratio MO _X / SiO ₂ when the silica is expressed by SiO ₂ and the inorganic compound other than silica is expressed in terms of oxide (MO _X ) is 0.0001 to 1.0, Preferably it is in the range of 0.001 to 0.3. It is difficult to obtain a porous particle having a molar ratio MO _X / SiO ₂ of less than 0.0001. Even if it is obtained, a pore volume is small and particles having a low refractive index cannot be obtained. In addition, when the molar ratio MO _X / SiO _{2 of} the porous particles exceeds 1.0, the ratio of silica decreases, so that the pore volume increases and it is difficult to obtain a material having a lower refractive index. is there.

  The pore volume of such porous particles is desirably in the range of 0.1 to 1.5 ml / g, preferably 0.2 to 1.5 ml / g. If the pore volume is less than 0.1 ml / g, particles having a sufficiently reduced refractive index cannot be obtained. If the pore volume exceeds 1.5 ml / g, the strength of the fine particles is lowered, and the strength of the resulting coating may be lowered. is there.

  In addition, the pore volume of such porous particles can be determined by a mercury intrusion method. Examples of the contents of the hollow particles include a solvent, a gas, and a porous substance used at the time of preparing the particles. The solvent may contain an unreacted particle precursor used when preparing the hollow particles, the catalyst used, and the like. Moreover, what consists of the compound illustrated by the said porous particle as a porous substance is mentioned. These contents may be composed of a single component or may be a mixture of a plurality of components.

  As a method for producing such hollow fine particles, for example, the method for preparing composite oxide colloidal particles disclosed in paragraphs [0010] to [0033] of JP-A-7-133105 is suitably employed. Specifically, when the composite particles are composed of silica and an inorganic compound other than silica, hollow fine particles are produced from the following first to third steps.

First Step: Preparation of Porous Particle Precursor In the first step, an alkali aqueous solution of a silica raw material and an inorganic compound raw material other than silica is separately prepared in advance, or a silica raw material and an inorganic compound raw material other than silica are prepared in advance. A mixed aqueous solution is prepared, and this aqueous solution is gradually added to an aqueous alkaline solution having a pH of 10 or more while stirring according to the composite ratio of the target composite oxide to prepare a porous particle precursor.

  As the silica raw material, alkali metal, ammonium or organic base silicate is used. Sodium silicate (water glass) or potassium silicate is used as the alkali metal silicate. Examples of the organic base include quaternary ammonium salts such as tetraethylammonium salt, and amines such as monoethanolamine, diethanolamine, and triethanolamine. The ammonium silicate or the organic base silicate includes an alkaline solution obtained by adding ammonia, a quaternary ammonium hydroxide, an amine compound or the like to a silicic acid solution.

  In addition, alkali-soluble inorganic compounds are used as raw materials for inorganic compounds other than silica. Specifically, an oxo acid of an element selected from Al, B, Ti, Zr, Sn, Ce, P, Sb, Mo, Zn, W, etc., an alkali metal salt or alkaline earth metal salt of the oxo acid, ammonium And salts and quaternary ammonium salts. More specifically, sodium aluminate, sodium tetraborate, zirconyl ammonium carbonate, potassium antimonate, potassium stannate, sodium aluminosilicate, sodium molybdate, cerium ammonium nitrate, and sodium phosphate are suitable.

Although the pH value of the mixed aqueous solution changes simultaneously with the addition of these aqueous solutions, an operation for controlling the pH value within a predetermined range is not particularly required. The aqueous solution finally has a pH value determined by the type of inorganic oxide and the mixing ratio thereof. There is no restriction | limiting in particular in the addition rate of the aqueous solution at this time. Further, in the production of composite oxide particles, a dispersion of seed particles can be used as a starting material. The seed particles are not particularly limited, but inorganic oxides such as SiO ₂ , Al ₂ O ₃ , TiO ₂ or ZrO ₂ or fine particles of these composite oxides are used. Usually, these sols are used. Can do. Furthermore, the porous particle precursor dispersion obtained by the above production method may be used as a seed particle dispersion. When using a seed particle dispersion, the pH of the seed particle dispersion is adjusted to 10 or higher, and then an aqueous solution of the compound is added to the above-mentioned alkaline aqueous solution while stirring. Also in this case, it is not always necessary to control the pH of the dispersion. When seed particles are used in this way, it is easy to control the particle size of the porous particles to be prepared, and particles with uniform particle sizes can be obtained.

  The silica raw material and the inorganic compound raw material described above have high solubility on the alkali side. However, when both are mixed in this highly soluble pH region, the solubility of oxo acid ions such as silicate ions and aluminate ions decreases, and these composites precipitate and grow into fine particles, or seed particles. It grows on the top and particle growth occurs. Therefore, it is not always necessary to perform pH control as in the conventional method for precipitation and growth of fine particles.

The composite ratio of silica and an inorganic compound other than silica in the first step is that the inorganic compound relative to silica is converted to an oxide (MO _X ), and the molar ratio of MO _X / SiO ₂ is 0.05 to 2.0, Preferably it is in the range of 0.2-2.0. Within this range, the pore volume of the porous particles increases as the proportion of silica decreases. However, even when the molar ratio exceeds 2.0, the pore volume of the porous particles hardly increases. On the other hand, when the molar ratio is less than 0.05, the pore volume becomes small. When preparing the hollow particles, the molar ratio of MO _X / SiO ₂ is preferably in the range of 0.25 to 2.0.

Second step: Removal of inorganic compound other than silica from porous particles In the second step, inorganic compounds other than silica (elements other than silicon and oxygen) are obtained from the porous particle precursor obtained in the first step. At least a portion is selectively removed. As a specific removal method, the inorganic compound in the porous particle precursor is dissolved and removed using a mineral acid or an organic acid, or is contacted with a cation exchange resin for ion exchange removal.

  The porous particle precursor obtained in the first step is a particle having a network structure in which silicon and an inorganic compound constituent element are bonded through oxygen. By removing the inorganic compound (elements other than silicon and oxygen) from the porous particle precursor in this way, porous particles having a larger porosity and a larger pore volume can be obtained. Further, if the amount of removing the inorganic oxide (elements other than silicon and oxygen) from the porous particle precursor is increased, the hollow particles can be prepared.

  In addition, prior to removing inorganic compounds other than silica from the porous particle precursor, fluorine-substituted, obtained by dealkalizing an alkali metal salt of silica into the porous particle precursor dispersion obtained in the first step. It is preferable to add a silicic acid solution containing an alkyl group-containing silane compound or a hydrolyzable organosilicon compound to form a silica protective film. The thickness of the silica protective film may be 0.5 to 15 nm. Even if the silica protective film is formed, the protective film in this step is porous and thin, so that it is possible to remove inorganic compounds other than silica described above from the porous particle precursor.

  By forming such a silica protective film, inorganic compounds other than silica described above can be removed from the porous particle precursor while maintaining the particle shape. Further, when forming the silica coating layer described later, the pores of the porous particles are not blocked by the coating layer, and therefore the silica coating layer described later is formed without reducing the pore volume. Can do. Note that when the amount of the inorganic compound to be removed is small, the particles are not broken, and thus it is not always necessary to form a protective film.

  When preparing hollow particles, it is desirable to form this silica protective film. When preparing the hollow particles, the inorganic compound is removed to obtain a hollow particle precursor composed of a silica protective film, a solvent in the silica protective film, and an undissolved porous solid content. When a coating layer to be described later is formed on the precursor, the formed coating layer becomes a particle wall to form hollow particles.

The amount of the silica source added for forming the silica protective film is preferably small as long as the particle shape can be maintained. If the amount of the silica source is too large, the silica protective film becomes too thick, and it may be difficult to remove inorganic compounds other than silica from the porous particle precursor. The hydrolyzable organic silicon compound used for the silica protective film formed of the general formula _{R n Si (OR ') 4} -n [R, R': an alkyl group, an aryl group, a vinyl group, such as acrylic group An alkoxysilane represented by a hydrocarbon group, n = 0, 1, 2, or 3] can be used. In particular, tetraalkoxysilanes such as fluorine-substituted tetramethoxysilane, tetraethoxysilane, and tetraisopropoxysilane are preferably used.

  As an addition method, a solution obtained by adding a small amount of alkali or acid as a catalyst to a mixed solution of these alkoxysilane, pure water, and alcohol is added to the dispersion of the porous particles, and the alkoxysilane is hydrolyzed. The produced silicic acid polymer is deposited on the surface of the inorganic oxide particles. At this time, alkoxysilane, alcohol, and catalyst may be simultaneously added to the dispersion. As the alkali catalyst, ammonia, an alkali metal hydroxide, or an amine can be used. As the acid catalyst, various inorganic acids and organic acids can be used.

  When the dispersion medium of the porous particle precursor is water alone or when the ratio of water to the organic solvent is high, a silica protective film can be formed using a silicic acid solution. When a silicic acid solution is used, a predetermined amount of the silicic acid solution is added to the dispersion, and at the same time an alkali is added to deposit the silicic acid solution on the surface of the porous particles. In addition, you may produce a silica protective film together using a silicic acid liquid and the said alkoxysilane.

Third step: Formation of silica coating layer In the third step, the porous particle dispersion prepared in the second step (in the case of hollow particles, the hollow particle precursor dispersion) contains a fluorine-substituted alkyl group-containing silane compound. By adding a hydrolyzable organosilicon compound or silicic acid solution, the surface of the particles is coated with a polymer such as a hydrolyzable organosilicon compound or silicic acid solution to form a silica coating layer.

The hydrolyzable organic silicon compound used for the silica coating layer formed, the above-mentioned such general formula _{R n Si (OR ') 4} -n [R, R': an alkyl group, an aryl group, a vinyl group, An alkoxysilane represented by a hydrocarbon group such as an acryl group, n = 0, 1, 2, or 3] can be used. In particular, tetraalkoxysilanes such as tetramethoxysilane, tetraethoxysilane, and tetraisopropoxysilane are preferably used.

  As an addition method, a solution obtained by adding a small amount of alkali or acid as a catalyst to a mixed solution of these alkoxysilane, pure water, and alcohol is used as a dispersion of the porous particles (in the case of hollow particles, a hollow particle precursor). In addition, the silicic acid polymer produced by hydrolyzing alkoxysilane is deposited on the surface of the porous particles (in the case of hollow particles, hollow particle precursors). At this time, alkoxysilane, alcohol, and catalyst may be simultaneously added to the dispersion. As the alkali catalyst, ammonia, an alkali metal hydroxide, or an amine can be used. As the acid catalyst, various inorganic acids and organic acids can be used.

  When the dispersion medium of porous particles (in the case of hollow particles, the hollow particle precursor) is water alone or a mixed solvent with an organic solvent and the mixed solvent has a high ratio of water to the organic solvent, a silicate solution You may form a coating layer using. The silicic acid solution is an aqueous solution of a low silicic acid polymer obtained by dealkalizing an aqueous solution of an alkali metal silicate such as water glass by ion exchange treatment.

  The silicic acid solution is added to the dispersion of porous particles (in the case of hollow particles, hollow particle precursors), and at the same time, alkali is added to make the low-silicic acid polymer into porous particles (in the case of hollow particles, hollow particle precursors). ) Deposit on the surface. In addition, you may use a silicic acid liquid for the coating layer formation in combination with the said alkoxysilane. The addition amount of the organosilicon compound or silicic acid solution used for forming the coating layer only needs to be sufficient to cover the surface of the colloidal particles, and the finally obtained silica coating layer has a thickness of 1 to 20 nm. In such an amount, it is added in a dispersion of porous particles (in the case of hollow particles, a hollow particle precursor). When the silica protective film is formed, the organosilicon compound or the silicate solution is added in such an amount that the total thickness of the silica protective film and the silica coating layer is in the range of 1 to 20 nm.

  Next, the dispersion liquid of the particles on which the coating layer is formed is heat-treated. By the heat treatment, in the case of porous particles, the silica coating layer covering the surface of the porous particles is densified, and a dispersion of composite particles in which the porous particles are coated with the silica coating layer is obtained. In the case of a hollow particle precursor, the formed coating layer is densified to form hollow particle walls, and a dispersion of hollow particles having cavities filled with a solvent, gas, or porous solid content is obtained.

  The heat treatment temperature at this time is not particularly limited as long as it can close the fine pores of the silica coating layer, and is preferably in the range of 80 to 300 ° C. When the heat treatment temperature is less than 80 ° C., the fine pores of the silica coating layer may not be completely closed and densified, and the treatment time may take a long time. Further, when the heat treatment temperature exceeds 300 ° C. for a long time, fine particles may be formed, and the effect of low refractive index may not be obtained.

  The refractive index of the inorganic fine particles thus obtained is as low as less than 1.42. Such inorganic fine particles are presumed to have a low refractive index because the porosity inside the porous particles is maintained or the inside is hollow. As the hollow silica-based fine particles, those commercially available from Catalyst Kasei Co., Ltd. can be preferably used.

  The content of the hollow silica-based fine particles having an outer shell layer and porous or hollow inside is preferably 10 to 50% by mass. In order to obtain the effect of a low refractive index, the content is preferably 15% by mass or more, and when it exceeds 50% by mass, the binder component is decreased and the film strength becomes insufficient. Most preferably, it is 20-50 mass%.

  As a method of adding to the low refractive index layer, for example, a solution obtained by adding a small amount of alkali or acid as a catalyst to a mixed solution of the tetraalkoxysilane, pure water, and alcohol is added to the dispersion of the hollow silica fine particles. The silicic acid polymer produced by hydrolyzing tetraalkoxysilane is deposited on the surface of the hollow silica fine particles. At this time, tetraalkoxysilane, alcohol, and catalyst may be simultaneously added to the dispersion. As the alkali catalyst, ammonia, an alkali metal hydroxide, or an amine can be used. As the acid catalyst, various inorganic acids and organic acids can be used.

  The silica-based fine particles may be those produced by the production method described in the WO2007 / 099814 pamphlet.

  Further, the low refractive index layer may contain a fluorine-substituted alkyl group-containing silane compound represented by the following general formula (OSi-2).

  The fluorine-substituted alkyl group-containing silane compound represented by the general formula (OSi-2) will be described.

In the formula, R ^{1 to} R ⁶ are alkyl groups having 1 to 16 carbon atoms, preferably 1 to 4 carbon atoms, halogenated alkyl groups having 1 to 6 carbon atoms, preferably 1 to 4 carbon atoms, and 6 to 12 carbon atoms, preferably 6 carbon atoms. 10 to 10 aryl groups, 7 to 14 carbon atoms, preferably 7 to 12 alkylaryl groups, arylalkyl groups, 2 to 8 carbon atoms, preferably 2 to 6 alkenyl groups, or 1 to 6 carbon atoms, preferably 1 to 3 alkoxy groups, a hydrogen atom or a halogen atom.

Rf represents-(CaHbFc)-, a is an integer of 1 to 12, b + c is 2a, b is an integer of 0 to 24, and c is an integer of 0 to 24. Such Rf is preferably a group having a fluoroalkylene group and an alkylene group. Specifically, examples of such fluorine-containing silicone compounds include (MeO) ₃ SiC ₂ H ₄ C ₂ F ₄ C ₂ H ₄ Si (MeO) ₃ , (MeO) ₃ SiC ₂ H ₄ C ₄ F ₈ C _{2 H 4 Si (MeO) 3} , (MeO) 3 SiC 2 H 4 C 6 F 12 C 2 H 4 Si (MeO) 3, (H 5 C 2 O) 3 SiC 2 H 4 C 4 F 8 C 2 H _{4 Si (OC 2 H 5)} 3, include methoxy disilane compound or the like represented by _{(H 5 C 2 O) 3} SiC 2 H 4 C 6 F 12 C 2 H 4 Si (OC 2 H 5) 3.

  If the fluorine-containing alkyl group-containing silane compound is included as a binder, the transparent film itself is hydrophobic, so the transparent film is not sufficiently densified and is porous or cracked. Even if it has a void or a void, entry into the transparent film by chemicals such as moisture, acid and alkali is suppressed. Furthermore, fine particles such as metals contained in the conductive layer which is the substrate surface or the lower layer do not react with chemicals such as moisture, acid and alkali. For this reason, such a transparent film has excellent chemical resistance.

  In addition, when a fluorine-substituted alkyl group-containing silane compound is included as a binder, not only the hydrophobic property but also the slipperiness (low contact resistance) is obtained, and thus a transparent film having excellent scratch strength can be obtained. Can do. Further, when the binder contains a fluorine-substituted alkyl group-containing silane compound having such a structural unit, when the conductive layer is formed in the lower layer, the shrinkage rate of the binder is equivalent to that of the conductive layer. Therefore, it is possible to form a transparent film having excellent adhesion to the conductive layer. Furthermore, when the transparent film is heat-treated, the conductive layer is not peeled off due to the difference in shrinkage rate, and a portion having no electrical contact is not generated in the transparent conductive layer. For this reason, sufficient electroconductivity can be maintained as a whole film.

  A transparent film containing a fluorine-substituted alkyl group-containing silane compound and hollow silica-based fine particles having the outer shell layer and being porous or hollow inside has high scratch strength and is evaluated by eraser strength or nail strength. The film strength is high, the pencil hardness is high, and a transparent film excellent in strength can be formed.

  The low refractive index layer may contain a silane coupling agent. Silane coupling agents include methyltrimethoxysilane, methyltriethoxysilane, methyltrimethoxyethoxysilane, methyltriacetoxysilane, methyltributoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, vinyltrimethoxysilane, vinyltrimethoxysilane. Ethoxysilane, vinyltriacetoxysilane, vinyltrimethoxyethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, phenyltriacetoxysilane, γ-chloropropyltrimethoxysilane, γ-chloropropyltriethoxysilane, γ-chloropropyltri Acetoxysilane, 3,3,3-trifluoropropyltrimethoxysilane, γ-glycidyloxypropyltrimethoxysilane, γ-glycidyloxypropyltri Ethoxysilane, γ- (β-glycidyloxyethoxy) propyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltriethoxysilane, γ- Acryloyloxypropyltrimethoxysilane, γ-methacryloyloxypropyltrimethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, N- Examples include β- (aminoethyl) -γ-aminopropyltrimethoxysilane and β-cyanoethyltriethoxysilane.

  Examples of silane coupling agents having a disubstituted alkyl group with respect to silicon include dimethyldimethoxysilane, phenylmethyldimethoxysilane, dimethyldiethoxysilane, phenylmethyldiethoxysilane, and γ-glycidyloxypropylmethyldiethoxysilane. Γ-glycidyloxypropylmethyldimethoxysilane, γ-glycidyloxypropylphenyldiethoxysilane, γ-chloropropylmethyldiethoxysilane, dimethyldiacetoxysilane, γ-acryloyloxypropylmethyldimethoxysilane, γ-acryloyloxypropylmethyldi Ethoxysilane, γ-methacryloyloxypropylmethyldimethoxysilane, γ-methacryloyloxypropylmethyldiethoxysilane, γ-mercaptopropylmethyldimeth Shishiran, .gamma.-mercaptopropyl methyl diethoxy silane, .gamma.-aminopropyl methyl dimethoxy silane, .gamma.-aminopropyl methyl diethoxy silane, methyl vinyl dimethoxy silane, and methyl vinyl diethoxy silane.

  Among these, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltriacetoxysilane, vinyltrimethoxyethoxysilane, γ-acryloyloxypropyltrimethoxysilane and γ-methacryloyloxypropyltrimethoxysilane having a double bond in the molecule. Γ-acryloyloxypropylmethyldimethoxysilane, γ-acryloyloxypropylmethyldiethoxysilane, γ-methacryloyloxypropylmethyldimethoxysilane, and γ-methacryloyloxypropylmethyldiethoxy having a disubstituted alkyl group with respect to silicon Silane, methylvinyldimethoxysilane and methylvinyldiethoxysilane are preferred, and γ-acryloyloxypropyltrimethoxysilane and γ-methacryloyloxyp Particularly preferred are propyltrimethoxysilane, γ-acryloyloxypropylmethyldimethoxysilane, γ-acryloyloxypropylmethyldiethoxysilane, γ-methacryloyloxypropylmethyldimethoxysilane and γ-methacryloyloxypropylmethyldiethoxysilane.

  Two or more coupling agents may be used in combination. In addition to the silane coupling agents shown above, other silane coupling agents may be used. Other silane coupling agents include alkyl esters of orthosilicate (eg, methyl orthosilicate, ethyl orthosilicate, n-propyl orthosilicate, i-propyl orthosilicate, n-butyl orthosilicate, sec-butyl orthosilicate, orthosilicate). Acid t-butyl) and its hydrolyzate.

The low refractive index layer may contain a silicon compound represented by CF ₃ (CF ₂ ) nCH ₂ CH ₂ Si (OR ₁ ) ₃ . (In the formula, R1 represents an alkyl group having 1 to 5 carbon atoms, and n represents an integer of 0 to 12.) Specific examples of the compound include trifluoropropyltrimethoxysilane and trifluoropropyl. Examples include triethoxysilane, tridecafluorooctyltrimethoxysilane, tridecafluorooctyltriethoxysilane, heptadecafluorodecyltrimethoxysilane, heptadecafluorodecyltriethoxysilane, and these are used alone or in combination of two or more. Can be used.

_{It may} also contain H 2 NCONH (CH) mSi ( OR2) silicon compound in the terminal position represented by ₃ having a ureido group _(H 2 NCONH-). (In the formula, R2 represents an alkyl group having 1 to 5 carbon atoms, and m represents an integer of 1 to 5.) Specific compounds include γ-ureidopropyltrimethoxysilane and γ-ureido. Examples thereof include propyltriethoxysilane and γ-ureidopropyltripropoxysilane. Among these, γ-ureidopropyltrimethoxysilane, γ-ureidopropyltriethoxysilane, and the like are particularly preferable.

  In addition, the low refractive index layer can use, for example, polyvinyl alcohol, polyoxyethylene, polymethyl methacrylate, polymethyl acrylate, fluoroacrylate, diacetyl cellulose, triacetyl cellulose, nitrocellulose, polyester, alkyd resin, etc. as a binder. .

  In addition, the low refractive index layer includes, for example, polyvinyl alcohol, polyoxyethylene, polymethyl methacrylate, polymethyl acrylate, fluoroacrylate, diacetyl cellulose, triacetyl cellulose, nitrocellulose, polyester, and alkyd resin as a binder.

  The low refractive index layer preferably contains 5 to 80% by mass of binder as a whole. The binder has a function of adhering the hollow silica-based fine particles and maintaining the structure of the low refractive index layer including voids. The usage-amount of a binder is suitably adjusted so that the intensity | strength of a low refractive index layer can be maintained, without filling a space | gap.

(solvent)
The low refractive index layer preferably contains an organic solvent. Specific examples of organic solvents include alcohols (eg, methanol, ethanol, isopropanol, butanol, benzyl alcohol), ketones (eg, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone), esters (eg, methyl acetate, ethyl acetate). , Propyl acetate, butyl acetate, methyl formate, ethyl formate, propyl formate, butyl formate), aliphatic hydrocarbons (eg, hexane, cyclohexane), halogenated hydrocarbons (eg, methylene chloride, chloroform, carbon tetrachloride), aromatic Group hydrocarbon (eg, benzene, toluene, xylene), amide (eg, dimethylformamide, dimethylacetamide, n-methylpyrrolidone), ether (eg, diethyl ether, dioxane, tetrahydrofuran), ether alcohol (eg, 1-methoxy-2-propanol). Of these, toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone and butanol are particularly preferable.

  The solid content concentration in the low refractive index layer coating composition is preferably 1 to 4% by mass. By making the solid content concentration 4% by mass or less, coating unevenness is less likely to occur, and the content is 1% by mass or more. By doing so, the drying load is reduced.

(High refractive index layer)
The antireflection layer may have the following high refractive index layer in addition to the above-described low refractive index layer.

  The high refractive index layer preferably contains metal oxide fine particles. The kind of metal oxide fine particles is not particularly limited, and Ti, Zr, Sn, Sb, Cu, Fe, Mn, Pb, Cd, As, Cr, Hg, Zn, Al, Mg, Si, P and S A metal oxide having at least one element selected from the group consisting of Al, In, Sn, Sb, Nb, a halogen element, Ta and the like is doped with a minute amount of atoms. May be. A mixture of these may also be used. In the present invention, at least one metal oxide fine particle selected from zirconium oxide, antimony oxide, tin oxide, zinc oxide, indium tin oxide (ITO), antimony doped tin oxide (ATO), and zinc antimonate is used. It is particularly preferable to use it as the main component. In particular, it is preferable to contain zinc antimonate particles.

  The average particle diameter of the primary particles of these metal oxide fine particles is in the range of 10 nm to 200 nm, particularly preferably 10 to 150 nm. The average particle diameter of the metal oxide fine particles can be measured from an electron micrograph taken with a scanning electron microscope (SEM) or the like. You may measure by the particle size distribution meter etc. which utilize a dynamic light scattering method, a static light scattering method, etc. If the particle size is too small, aggregation tends to occur and the dispersibility deteriorates. If the particle size is too large, the haze is remarkably increased. The shape of the metal oxide fine particles is preferably a rice grain shape, a spherical shape, a cubic shape, a spindle shape, a needle shape, or an indefinite shape.

  Specifically, the refractive index of the high refractive index layer is higher than the refractive index of the film as the support, and is preferably in the range of 1.5 to 2.2 when measured at 23 ° C. and a wavelength of 550 nm. The means for adjusting the refractive index of the high refractive index layer is that the kind and addition amount of the metal oxide fine particles are dominant, so that the refractive index of the metal oxide fine particles is preferably 1.80 to 2.60, More preferably, it is 1.85 to 2.50.

  The metal oxide fine particles may be surface-treated with an organic compound. By modifying the surface of the metal oxide fine particles with an organic compound, the dispersion stability in an organic solvent is improved, the dispersion particle size can be easily controlled, and aggregation and sedimentation over time can be suppressed. . For this reason, the surface modification amount with a preferable organic compound is 0.1 mass%-5 mass% with respect to metal oxide particle, More preferably, it is 0.5 mass%-3 mass%. Examples of the organic compound used for the surface treatment include polyols, alkanolamines, stearic acid, silane coupling agents, and titanate coupling agents. Of these, silane coupling agents are preferred. Two or more kinds of surface treatments may be combined.

  The thickness of the high refractive index layer containing the metal oxide fine particles is preferably 5 nm to 1 μm, more preferably 10 nm to 0.2 μm, and most preferably 30 nm to 0.1 μm.

  The ratio of the metal oxide fine particles to be used and a binder such as actinic ray curable resin to be described later varies depending on the kind of metal oxide fine particles, the particle size, etc., but the volume ratio of the former 1 to the latter 2 to the former 2 The latter one is preferable.

  The amount of the metal oxide fine particles used in the present invention is preferably 5% by mass to 85% by mass in the high refractive index layer, more preferably 10% by mass to 80% by mass, and most preferably 20% to 75% by mass. preferable. If the amount used is small, the desired refractive index and the effect of the present invention cannot be obtained, and if it is too large, the film strength deteriorates.

  The metal oxide fine particles are supplied to a coating solution for forming a high refractive index layer in a dispersion state dispersed in a medium. As a dispersion medium for metal oxide particles, it is preferable to use a liquid having a boiling point of 60 to 170 ° C. Specific examples of the dispersion solvent include water, alcohol (eg, methanol, ethanol, isopropanol, butanol, benzyl alcohol), ketone (eg, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone), ketone alcohol (eg, diacetone alcohol). , Esters (eg, methyl acetate, ethyl acetate, propyl acetate, butyl acetate, methyl formate, ethyl formate, propyl formate, butyl formate), aliphatic hydrocarbons (eg, hexane, cyclohexane), halogenated hydrocarbons (eg, methylene) Chloride, chloroform, carbon tetrachloride), aromatic hydrocarbons (eg, benzene, toluene, xylene), amides (eg, dimethylformamide, dimethylacetamide, n-methylpyrrolidone), ethers (eg, diethyl ether, dioxane, Tiger hydrofuran), ether alcohols (e.g., 1-methoxy-2-propanol), propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate. Of these, toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone and butanol are particularly preferable.

  The metal oxide fine particles can be dispersed in the medium using a disperser. Examples of the disperser include a sand grinder mill (eg, a bead mill with pins), a high-speed impeller mill, a pebble mill, a roller mill, an attritor, and a colloid mill. A sand grinder mill and a high-speed impeller mill are particularly preferred. Further, preliminary dispersion processing may be performed. Examples of the disperser used for the preliminary dispersion treatment include a ball mill, a three-roll mill, a kneader, and an extruder. It is also preferable to contain a dispersant.

  In the present invention, metal oxide fine particles having a core / shell structure may be further contained. One layer of the shell may be formed around the core, or a plurality of layers may be formed in order to further improve the light resistance. The core is preferably completely covered by the shell.

  For the core, titanium oxide (rutile type, anatase type, amorphous type, etc.), zirconium oxide, zinc oxide, cerium oxide, indium oxide doped with tin, tin oxide doped with antimony, etc. can be used. Titanium may be the main component.

  The shell is preferably formed of a metal oxide or sulfide containing an inorganic compound other than titanium oxide as a main component. For example, an inorganic compound mainly composed of silicon dioxide (silica), aluminum oxide (alumina) zirconium oxide, zinc oxide, tin oxide, antimony oxide, indium oxide, iron oxide, zinc sulfide, or the like is used. Of these, alumina, silica, and zirconia (zirconium oxide) are preferable. A mixture of these may also be used.

  The coating amount of the shell with respect to the core is 2 to 50% by mass as an average coating amount. Preferably it is 3-40 mass%, More preferably, it is 4-25 mass%. When the coating amount of the shell is large, the refractive index of the fine particles is lowered, and when the coating amount is too small, the light resistance is deteriorated. Two or more inorganic fine particles may be used in combination.

  The titanium oxide used as a core can use what was produced by the liquid phase method or the gaseous-phase method. As a method for forming the shell around the core, for example, U.S. Pat. No. 3,410,708, JP-B-58-47061, U.S. Pat. No. 2,885,366, and U.S. Pat. No. 1, British Patent No. 1,134,249, US Pat. No. 3,383,231, British Patent No. 2,629,953, No. 1,365,999, etc. Can do.

  The high refractive index layer or the low refractive index layer described above can contain a compound represented by the following general formula (CL1) or a chelate compound thereof, and can improve physical properties such as hardness.

Formula (CL1) _An MB _x-n
In the formula, M represents a metal atom, A represents a hydrolyzable functional group or a hydrocarbon group having a hydrolyzable functional group, and B represents an atomic group covalently or ionically bonded to the metal atom M. x represents the valence of the metal atom M, and n represents an integer of 2 or more and x or less.

  Examples of the hydrolyzable functional group A include halogens such as alkoxyl groups and chloro atoms, ester groups and amide groups. The metal compound belonging to the general formula (CL1) includes an alkoxide having two or more alkoxyl groups directly bonded to a metal atom, or a chelate compound thereof. Preferable metal compounds include titanium alkoxide, zirconium alkoxide, or chelate compounds thereof. Titanium alkoxide has a high reaction rate and a high refractive index and is easy to handle. However, since it has a photocatalytic action, its light resistance deteriorates when added in a large amount. Zirconium alkoxide has a high refractive index but tends to become cloudy, so care must be taken in dew point management during coating. Moreover, since titanium alkoxide has the effect of promoting the reaction of the ultraviolet curable resin and metal alkoxide, the physical properties of the coating film can be improved by adding a small amount.

  Examples of the titanium alkoxide include tetramethoxy titanium, tetraethoxy titanium, tetra-iso-propoxy titanium, tetra-n-propoxy titanium, tetra-n-butoxy titanium, tetra-sec-butoxy titanium, tetra-tert-butoxy titanium, and the like. Is mentioned.

  Examples of the zirconium alkoxide include tetramethoxy zirconium, tetraethoxy zirconium, tetra-iso-propoxy zirconium, tetra-n-propoxy zirconium, tetra-n-butoxy zirconium, tetra-sec-butoxy zirconium, tetra-tert-butoxy zirconium and the like. Is mentioned.

  Preferred chelating agents for forming a chelate compound by coordination with a free metal compound include alkanolamines such as diethanolamine and triethanolamine, glycols such as ethylene glycol, diethylene glycol and propylene glycol, acetylacetone and acetoacetic acid. Examples thereof include ethyl and the like having a molecular weight of 10,000 or less. By using these chelating agents, it is possible to form a chelate compound that is stable against water mixing and is excellent in the effect of reinforcing the coating film.

  The addition amount of the metal compound is preferably adjusted so that the content of the metal oxide derived from the metal compound contained in the high refractive index layer is 0.3 to 5% by mass. If it is less than 0.3% by mass, the scratch resistance is insufficient, and if it exceeds 5% by mass, the light resistance tends to deteriorate.

  The high refractive index layer preferably contains an actinic ray curable resin as a binder for the metal oxide fine particles in order to improve the film formability and physical properties of the coating film. As the actinic ray curable resin, a monomer or oligomer having two or more functional groups that cause a polymerization reaction directly by irradiation with actinic rays such as ultraviolet rays or electron beams or indirectly by the action of a photopolymerization initiator is used. be able to. In the present invention, a polyol acrylate, an epoxy acrylate, a urethane acrylate, a polyester acrylate or a mixture thereof is preferable. For example, the polyfunctional acrylate compound described in the hard coat layer is preferable.

  The addition amount of the actinic ray curable resin is preferably 15% by mass or more and less than 50% by mass in the solid content in the high refractive index composition.

  In order to accelerate curing of the actinic ray curable resin, it is preferable to contain a photopolymerization initiator and an acrylic compound having two or more polymerizable unsaturated bonds in the molecule in a mass ratio of 3: 7 to 1: 9. .

  In order to accelerate the curing of the actinic ray curable resin, it is preferable to contain a photopolymerization initiator. The addition amount of the photopolymerization initiator is preferably contained in a mass ratio of photopolymerization initiator: active light curable resin = 3: 7 to 1: 9.

  Specific examples of the photopolymerization initiator include acetophenone, benzophenone, hydroxybenzophenone, Michler's ketone, α-amyloxime ester, thioxanthone, and derivatives thereof, but are not particularly limited thereto.

  Examples of the organic solvent used for coating the high refractive index layer include alcohols (for example, methanol, ethanol, propanol, isopropanol, butanol, isobutanol, secondary butanol, tertiary butanol, pentanol, hexanol, cyclohexanol). , Benzyl alcohol, etc.), polyhydric alcohols (for example, ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, polypropylene glycol, butylene glycol, hexanediol, pentanediol, glycerin, hexanetriol, thio Diglycol, etc.), polyhydric alcohol ethers (eg, ethylene glycol monomethyl ether, Lenglycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monomethyl ether, diethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monobutyl ether, ethylene glycol monomethyl ether acetate, triethylene glycol monomethyl ether, triethylene glycol monoethyl Ether, ethylene glycol monophenyl ether, propylene glycol monophenyl ether, etc.), amines (for example, ethanolamine, diethanolamine, triethanolamine, N-methyldiethanolamine, N-ethyldiethanolamine, morpholine, N-ethylmorpholine, ether) Range amine, diethylenediamine, triethylenetetramine, tetraethylenepentamine, polyethyleneimine, pentamethyldiethylenetriamine, tetramethylpropylenediamine, etc.), amides (eg, formamide, N, N-dimethylformamide, N, N-dimethylacetamide, etc.) ), Heterocyclic rings (for example, 2-pyrrolidone, N-methyl-2-pyrrolidone, cyclohexyl pyrrolidone, 2-oxazolidone, 1,3-dimethyl-2-imidazolidinone), sulfoxides (for example, dimethyl sulfoxide) , Sulfones (e.g., sulfolane), urea, acetonitrile, acetone and the like, and alcohols, polyhydric alcohols, and polyhydric alcohol ethers are particularly preferable.

[Conductive layer]
The conductive layer can be provided on the film substrate, for example, between the film substrate and the hard coat layer, between the hard coat layer and the antireflection layer, or the side on which the antireflection layer is provided. It can be coated on the opposite side of the film substrate.

  The conductive layer provides a function to prevent the hard coat film from being charged when handling a support (resin film, etc.), and specifically includes an ionic conductive material and conductive fine particles. This is done by providing a layer to be used. Here, the ion conductive substance is a substance that shows electric conductivity and contains ions that are carriers for carrying electricity, and examples include ionic polymer compounds.

The surface specific resistance of the conductive layer is preferably adjusted to 10 ¹¹ Ω / □ (25 ° C., 55% RH) or less, more preferably 10 ¹⁰ Ω / □ (25 ° C., 55% RH) or less. Particularly preferably, it is 10 ⁹ Ω / □ (25 ° C., 55% RH) or less.

  Here, although details of the measurement of the surface specific resistance value are described in the Examples, the sample was conditioned for 24 hours under the conditions of 25 ° C. and 55% RH, and a terraohm meter model VE-30 manufactured by Kawaguchi Electric Co., Ltd. was used. Use to measure.

  On the conductive layer, an overcoat layer is further provided as the outermost surface layer. The surface specific resistance value is measured by substantially conducting the surface specific resistance value on the outermost surface layer on the side where the conductive layer is provided. It is defined as the surface resistivity value of the conductive layer.

  In order to adjust the surface specific resistance value of the conductive layer to the above-described range, conductive materials as shown below are preferably used.

  As the conductive material, the above-described π-conjugated conductive polymer, ionic polymer compound, metal oxide, and the like are preferably used.

  Examples of the ionic polymer compound include anionic polymer compounds such as those described in JP-B-49-23828, JP-A-49-23827, and JP-A-47-28937; JP-B-55-734, JP-A-50-54672 Ionene type polymers having a dissociating group in the main chain, as seen in JP-B Nos. 59-14735, 57-18175, 57-18176, 57-56059, etc .; No. 57-15376, No. 53-45231, No. 55-145783, No. 55-65950, No. 55-67746, No. 57-11342, No. 57-19735, No. 58-56858. No., JP-A 61-27853, 62-9346, and a cationic pendant type poly having a cationic dissociation group in the side chain. Chromatography; and the like.

  Particularly preferred ionic polymer compounds include polymers having units of the following general formulas [P], [Pa] and [Pb].

In the formula, R ₃ , R ₄ , R ₅ and R ₆ represent a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms, and R ₃ and R ₄ and / or R ₅ and R ₆ are bonded to each other, such as piperazine. A nitrogen-containing heterocycle may be formed. A, B and D are each a substituted or unsubstituted alkylene group having 2 to 10 carbon atoms, an arylene group, an alkenylene group, an arylenealkylene _{group, -R 7 COR 8 -, -} R 9 COOR 10 OCOR 11 -, - R 12 _{OCR 13 COOR 14 -, - R} 15 - (oR 16) m -, - R 17 CONHR 18 NHCOR 19 -, - R 20 OCONHR 21 NHCOR 22 - or _{-R 25} NHCONHR ₂₄ NHCONHR 25 - represents a. R ₇ , R ₈ , R ₉ , R ₁₁ , R ₁₂ , R ₁₄ , R ₁₅ , R ₁₆ , R ₁₇ , R ₁₉ , R ₂₀ , R ₂₂ , R ₂₃ and R ₂₅ are alkylene groups, R ₁₀ , R ₁₃ , R ₁₈ , R ₂₁ and R ₂₄ are each a linking group selected from a substituted or unsubstituted alkylene group, alkenylene group, arylene group, arylene alkylene group and alkylene arylene group, and m represents a positive integer of 1 to 4. , X ⁻ represents an anion.

  However, when A is an alkylene group, a hydroxyalkylene group or an arylenealkylene group, it is preferable that B is not an alkylene group, a hydroxylalkylene group or an arylenealkylene group.

E represents a simple bond, —NHCOR ₂₆ CONH— or a group selected from D. R ₂₆ represents a substituted or unsubstituted alkylene group, alkenylene group, arylene group, arylene alkylene group, or alkylene arylene group.

Z ₁ and Z ₂ are linked to E in the form of a quaternary salt of a group of nonmetal atoms (≡N ⁺ [X ⁻ ] ⁻ necessary for forming a 5-membered or 6-membered ring together with —N═C— group. May be).

  n represents an integer of 5 to 300.

  Among them, a quaternary ammonium cationic polymer having molecular crosslinking is particularly preferable, and a quaternary ammonium cationic polymer not containing chlorine ions and having molecular crosslinking is particularly preferably used from the viewpoint of environmental safety such as prevention of dioxin generation.

  Specific examples of the ionic polymer compound used in the present invention are listed below, but the present invention is not limited to these.

The ionic polymer compound may be used alone, or several types of ionic polymer compounds may be used in combination. The content of the ionic polymer compound in the resin film is preferably 0.02 g to 1.0 g / m ² , particularly preferably 0.02 g to 0.5 g / m ² .

The conductive material contains at least one element selected from the group consisting of Sn, Ti, In, Al, Zn, Si, Mg, Ba, Mo, W and V as a main component, and has a volume. A conductive material having a resistivity of 10 ⁷ Ω · cm or less is preferably used.

  Examples of the conductive material include metal oxides and composite oxides having the above elements.

Examples of metal oxides are preferably ZnO, TiO ₂ , SnO ₂ , Al ₂ O ₃ , In ₂ O ₃ , SiO ₂ , MgO, BaO, MoO ₂ , V ₂ O ₅ , or a composite oxide thereof. In particular, ZnO, TiO ₂ and SnO ₂ are preferred. Examples of containing different atoms include, for example, addition of Al, In, etc. to ZnO, addition of Nb, Ta, etc. to TiO ₂ , and addition of Sb, Nb, halogen elements, etc. to SnO ₂ . Addition is effective. The amount of these different atoms added is preferably in the range of 0.01 to 25 mol%, particularly preferably in the range of 0.1 to 15 mol%.

In addition, the volume resistivity of these metal oxide powders having conductivity is 10 ⁷ Ω · cm or less, particularly 10 ⁵ Ω · cm or less.

  Further, fine particles may be added to the conductive layer. Examples thereof include fine particles containing silica, colloidal silica, alumina, alumina sol, kaolin, talc, mica, calcium carbonate and the like as constituent components.

  The average particle diameter of the fine particles described above is preferably 0.01 μm to 10 μm, more preferably 0.01 μm to 5 μm, and the addition amount is 0.05 part to 10 parts by mass with respect to the solid content in the coating agent. Parts are preferred, with 0.1 to 5 parts being particularly preferred.

  Moreover, in order for a conductive layer to show sufficient antistatic effect and to maintain easy adhesion with an overcoat layer, it is preferable to contain a cellulose ester resin or an acrylic resin.

  Examples of the cellulose ester resin include cellulose derivatives such as cellulose diacetate, cellulose triacetate, cellulose acetate propionate, cellulose acetate butyrate, cellulose acetate phthalate, and cellulose nitrate.

  Examples of the acrylic resin include Acrypet MD, VH, MF, V (Mitsubishi Rayon Co., Ltd.), Hyperl M4003, M-4005, M-4006, M-4202, M-5000, M -5001, M-4501 (manufactured by Negami Kogyo Co., Ltd.), Dialnal BR-50, BR-52, BR-53, BR-60, BR-64, BR-73, BR-75, BR-77, BR- 79, BR-80, BR-82, BR-83, BR-85, BR-87, BR-88, BR-90, BR-93, BR-95, BR-100, BR-101, BR-102, BR-105, BR-106, BR-107, BR-108, BR-112, BR-113, BR-115, BR-116, BR-117, BR-118, etc. (Mitsubishi Rayon Co., Ltd.) Various homopolymers and copolymers to produce Le and methacrylic monomer as a raw material is preferably used.

  The resin used here is preferably 60% by mass or more, more preferably 80% by mass or more of the total resin used in the conductive layer, and an actinic ray curable resin or thermosetting resin is added as necessary. You can also These resins are coated as a binder in a state dissolved in the following solvent.

  For the coating composition for coating the conductive layer, the following solvents are preferably used. As the solvent, hydrocarbons, alcohols, ketones, esters, glycol ethers, and other solvents (methylene chloride) can be appropriately mixed and used, but are not particularly limited thereto.

  Examples of the hydrocarbons include benzene, toluene, xylene, hexane, cyclohexane and the like, and examples of alcohols include methanol, ethanol, n-propyl alcohol, iso-propyl alcohol, n-butanol, 2-butanol, tert- Examples include butanol, pentanol, 2-methyl-2-butanol, and cyclohexanol. Examples of ketones include acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone. Examples of esters include methyl formate, ethyl formate, Examples thereof include methyl acetate, ethyl acetate, isopropyl acetate, amyl acetate, ethyl lactate, and methyl lactate. Examples of glycol ethers (C1 to C4) include methyl cellosolve, ethyl cellosolve, propylene glycol monomethyl ester. As terrestrial (PGME), propylene glycol monoethyl ether, propylene glycol mono-n-propyl ether, propylene glycol monoisopropyl ether, propylene glycol monobutyl ether, or propylene glycol mono (C1-C4) alkyl ether esters, propylene glycol monomethyl Examples of ether acetate, propylene glycol monoethyl ether acetate, and other solvents include methylene chloride and N-methylpyrrolidone. Although not particularly limited to these, a solvent in which these are appropriately mixed is also preferably used.

  As a coating method of the conductive layer coating composition, using a gravure coater, dip coater, wire bar coater, reverse coater, extrusion coater, etc., the coating solution film thickness (sometimes referred to as wet film thickness) is 1 to 100 μm. In particular, 5 to 30 μm is preferable.

[Back coat layer]
In the hard coat film of the present invention, a back coat layer is preferably provided on the surface opposite to the side on which the hard coat layer is provided. The back coat layer is provided in order to correct curling caused by providing a hard coat layer or other layers. That is, the degree of curling can be balanced by imparting the property of being rounded with the surface on which the backcoat layer is provided facing inward. The back coat layer is preferably applied also as an anti-blocking layer. In this case, it is preferable that fine particles are added to the back coat layer coating composition in order to provide an anti-blocking function.

  As fine particles added to the back coat layer, examples of inorganic compounds include silicon dioxide, titanium dioxide, aluminum oxide, zirconium oxide, calcium carbonate, calcium carbonate, talc, clay, calcined kaolin, calcined calcium silicate, tin oxide, and oxidation. Mention may be made of indium, zinc oxide, ITO, hydrated calcium silicate, aluminum silicate, magnesium silicate and calcium phosphate.

  These fine particles are commercially available under the trade names of, for example, Aerosil R972, R972V, R974, R812, 200, 200V, 300, R202, OX50, and TT600 (manufactured by Nippon Aerosil Co., Ltd.). . Zirconium oxide fine particles are commercially available, for example, under the trade names Aerosil R976 and R811 (manufactured by Nippon Aerosil Co., Ltd.) and can be used. Examples of the polymer include silicone resin, fluororesin, and acrylic resin. Silicone resins are preferable, and those having a three-dimensional network structure are particularly preferable. For example, Tospearl 103, 105, 108, 120, 145, 3120, and 240 (manufactured by Toshiba Silicone Co., Ltd.) It is marketed by name and can be used.

  Among these, Aerosil 200V and Aerosil R972V are particularly preferably used because they have a large anti-blocking effect while keeping haze low. In the hard coat film of the present invention, the dynamic friction coefficient on the back side of the actinic ray curable resin layer is preferably 0.9 or less, particularly preferably 0.1 to 0.9.

  The fine particles contained in the backcoat layer are preferably contained in an amount of 0.1 to 50% by mass, more preferably 0.1 to 10% by mass with respect to the binder. The increase in haze when a backcoat layer is provided is preferably 1% or less, more preferably 0.5% or less, and particularly preferably 0.0 to 0.1%.

  Examples of the solvent used for coating the backcoat layer include dioxane, acetone, methyl ethyl ketone, methyl isobutyl ketone, N, N-dimethylformamide, methyl acetate, ethyl acetate, trichloroethylene, methylene chloride, ethylene chloride, tetrachloroethane, trichloroethane, Chloroform, water, methanol, ethanol, n-propyl alcohol, i-propyl alcohol, n-butanol, cyclohexanone, cyclohexanol, propylene glycol monomethyl ether, propylene glycol monoethyl ether, or hydrocarbons (toluene, xylene) Are used in appropriate combinations.

  It is preferable to apply these coating compositions on the surface of the hard coat film with a gravure coater, dip coater, reverse coater, wire bar coater, die coater, spray coating, ink jet coating or the like with a wet film thickness of 1 to 100 μm. Is particularly preferably 5 to 30 μm.

  Examples of the resin used as the binder of the backcoat layer include vinyl chloride-vinyl acetate copolymer, vinyl chloride resin, vinyl acetate resin, vinyl acetate-vinyl alcohol copolymer, partially hydrolyzed vinyl chloride-vinyl acetate copolymer. Polymer, vinyl chloride-vinylidene chloride copolymer, vinyl chloride-acrylonitrile copolymer, ethylene-vinyl alcohol copolymer, chlorinated polyvinyl chloride, ethylene-vinyl chloride copolymer, ethylene-vinyl acetate copolymer, etc. Vinyl polymer or copolymer, nitrocellulose, cellulose acetate propionate (preferably acetyl group substitution degree 1.8-2.3, propionyl group substitution degree 0.1-1.0), diacetyl cellulose, cellulose Cellulose derivatives such as acetate butyrate resin, maleic acid and / or Or acrylic acid copolymer, acrylic ester copolymer, acrylonitrile-styrene copolymer, chlorinated polyethylene, acrylonitrile-chlorinated polyethylene-styrene copolymer, methyl methacrylate-butadiene-styrene copolymer, acrylic resin , Polyvinyl alcohol resin, polyvinyl acetal resin, polyvinyl butyral resin, urethane resin, polyester polyurethane resin, polyether polyurethane resin, polycarbonate polyurethane resin, polyester resin, polyether resin, polyamide resin, amino resin, styrene-butadiene resin, butadiene-acrylonitrile Examples thereof include, but are not limited to, rubber resins such as resins, silicone resins, fluorine resins, and the like. For example, as an acrylic resin, Acrypet MD, VH, MF, V (manufactured by Mitsubishi Rayon Co., Ltd.), Hyperl M-4003, M-4005, M-4006, M-4202, M-5000, M-5001, M-4501 (manufactured by Negami Kogyo Co., Ltd.), Dialnal BR-50, BR-52, BR-53, BR-60, BR-64, BR-73, BR-75, BR-77, BR-79, BR -80, BR-82, BR-83, BR-85, BR-87, BR-88, BR-90, BR-93, BR-95, BR-100, BR-101, BR-102, BR-105 BR-106, BR-107, BR-108, BR-112, BR-113, BR-115, BR-116, BR-117, BR-118, etc. (Mitsubishi Rayon Co., Ltd.) acrylic and The methacrylic monomers are commercially available various homopolymers and copolymers, etc. was prepared as a raw material, it is also possible to select a preferred mono from this appropriate. For example, as a resin used as a binder, it is preferable to use a blend of acetylated cellulose such as cellulose diacetate and cellulose acetate prohyonate and an acrylic resin, and fine particles made of an acrylic resin are used to refract the fine particles and the binder. By making the rate difference 0 to less than 0.02, a highly transparent back coat layer can be obtained.

  The order in which the backcoat layer is applied may be before or after the hardcoat layer is applied, but when the backcoat layer also serves as an anti-blocking layer, it is preferably applied first. Alternatively, the backcoat layer can be applied in two or more steps. Moreover, it is also preferable that the backcoat layer also serves as an easy-adhesion layer for improving the adhesion with the polarizer.

(Reflectivity of antireflection layer)
The reflectance of the antireflection layer can be measured with a spectrophotometer. At that time, after the surface on the measurement side of the sample is roughened, the light absorption treatment is performed using a black spray, and then the reflected light in the visible light region (400 to 700 nm) is measured. The reflectance is preferably as low as possible, but the average value in the visible light wavelength is preferably 1.5% or less, and the minimum reflectance is preferably 0.8% or less. Moreover, it is preferable to have a flat reflection spectrum in the wavelength region of visible light.

  In addition, the reflection hue on the surface of the display device that has been subjected to the antireflection treatment is often colored red or blue because the reflectance in the short wavelength region and the long wavelength region is high in the visible light region due to the design of the antireflection film. The color tone of the reflected light varies depending on the application, and when used on the outermost surface of a flat-screen television or the like, a neutral color tone is preferred. In this case, generally preferred reflection hue ranges are 0.17 ≦ x ≦ 0.27 and 0.07 ≦ y ≦ 0.17 on the XYZ color system (CIE1931 color system).

  The film thicknesses of the high refractive index layer and the low refractive index layer can be obtained by calculation according to a conventional method in consideration of the reflectance and the color of reflected light based on the refractive index of each layer.

(Surface treatment and coating)
You may surface-treat before apply | coating each layer. Examples of the surface treatment method include a cleaning method, an alkali treatment method, a flame plasma treatment method, a high frequency discharge plasma method, an electron beam method, an ion beam method, a sputtering method, an acid treatment, a corona treatment method, and an atmospheric pressure glow discharge plasma method. It is done.

  The corona treatment can be performed using a corona treatment having a multi-knife electrode of SOFTAL (Sophthal), an apparatus commercially available from Kasuga Electric Co., Ltd., Toyo Electric Co., Ltd., or the like. The intensity of the corona discharge treatment depends on the distance between the electrodes, the output per unit area, and the generator frequency.

As one electrode (A electrode) of the corona treatment apparatus, a commercially available one can be used, but the material can be selected from aluminum, stainless steel and the like. The other is an electrode (B electrode) for holding a plastic film, and is a roll electrode installed at a certain distance from the A electrode so that the corona treatment is carried out stably and uniformly. A commercially available one can also be used, and the material is preferably a roll made of ceramic, silicon, EPT rubber, hyperon rubber or the like on a roll made of aluminum, stainless steel, or a metal thereof. It is done. The frequency used for the corona treatment is a frequency of 20 kHz or more and 100 kHz or less, and a frequency of 30 kHz to 60 kHz is preferable. When the frequency is lowered, the uniformity of the corona treatment is deteriorated and unevenness of the corona treatment occurs. In addition, when the frequency is increased, there is no particular problem when performing high-output corona treatment, but when performing low-output corona treatment, it becomes difficult to perform stable processing, resulting in uneven processing. Occurs. The output of the corona treatment is 10 to 500 W · min. / M ² but 20 to 400 W · min. An output of / m ² is preferred. The distance between the electrode and the film is 5 mm or more and 50 mm or less, preferably 10 mm or more and 35 mm or less. When the gap opens, a higher voltage is required to maintain a constant output, and unevenness is likely to occur. On the other hand, if the gap is too narrow, the applied voltage becomes too low and unevenness is likely to occur. Further, when the film is transported and continuously processed, the film comes into contact with the electrodes and scratches are generated.

  As an alkali treatment method, the film is generally immersed in an alkali solution, then washed with water and dried. Further, after the alkali treatment, neutralization in an acidic water step may be performed, followed by washing with water and drying. Examples of the alkaline solution include a potassium hydroxide solution and a sodium hydroxide solution, and the prescribed concentration of hydroxide ions is preferably 0.1 to 3N, and more preferably 0.5N to 2N. Adhesiveness between the hard coat layer and the low refractive index layer can be obtained by setting the content in the above range. The temperature of the alkaline solution is preferably in the range of 25 to 90 ° C., more preferably 40 to 70 ° C., from the viewpoint of precipitation of the alkaline solution. The alkali treatment time is 5 seconds to 5 minutes, preferably 30 seconds to 3 minutes.

  Moreover, you may use the method as described in Unexamined-Japanese-Patent No. 2003-313326 and Unexamined-Japanese-Patent No. 2007-332253, for example, for alkali treatment.

  Plasma treatments such as flame plasma treatment, high-frequency discharge plasma, and atmospheric pressure glow discharge plasma are disclosed in JP-A-2004-352777, JP-A-2004-352777, JP-A-2007-314707, and the like. You can refer to the technology. Moreover, AP-T series etc. which are the atmospheric pressure plasma processing apparatus by Sekisui Chemical Co., Ltd. can be used as a processing apparatus. These surface treatments are preferably used when an antireflection layer is provided on the hard coat layer of the hard coat film produced by the production method of the present invention. Further, as the treatment in that case, an alkali saponification treatment method and Plasma treatment is preferred.

  Each layer of the antireflection layer uses a dip coating method, an air knife coating method, a curtain coating method, a roller coating method, a wire bar coating method, a gravure coating method, a micro gravure coating method and an extrusion coating method on a film substrate. And can be formed by coating. At the time of application, it is preferable that the hard coat film is unwound in a roll shape with a width of 1.4 to 4 m, applied, dried and cured, and then wound into a roll shape. .

  Furthermore, the hard coat film of this invention may heat-process at 50-160 degreeC in the state wound up in roll shape, after laminating | stacking the said antireflection layer on a film surface. The period of the heat treatment may be appropriately determined depending on the set temperature. For example, if it is 50 ° C., it preferably ranges from 3 days to less than 30 days, and if it is 160 ° C., it ranges from 10 minutes to 1 day. preferable. Usually, it is preferably set at a relatively low temperature so that the heat treatment effect at the outside of the winding, the center of the winding, and the core is not biased, and is preferably performed at around 50 to 60 ° C. for about 7 days.

<< Transparent film substrate >>
The base film used for the production of the hard coat film is preferably easy to produce, optically isotropic, such as a hard coat layer or an antireflection layer, and preferably optically transparent. . Any of these may be used, for example, cellulose ester films such as cellulose diacetate film, cellulose acetate butyrate film, cellulose triacetate film, polyester film, polycarbonate film, polyarylate film, polysulfone. Film (including polyethersulfone), polyester film such as polyethylene terephthalate, polyethylene naphthalate, polyethylene film, polypropylene film, cellophane, polyvinylidene chloride film, polyvinyl alcohol film, ethylene vinyl alcohol film, syndiotactic polystyrene film, Norbornene resin film, polymethylpentene film, polyether ketone film Lum, polyether ketone imide film, a polyamide film, a fluororesin film, a nylon film, a cycloolefin polymer film, polymethyl methacrylate film or there may be mentioned acrylic film or the like, but are not limited to. Among these, cellulose ester films (for example, Konica Minoltak KC8UX2M, KC4UX2M, KC4UY, KC8UT, KC5UN, KC12UR, KC8UCR-3, KC8UCR-4 (above, manufactured by Konica Minolta Opto Co., Ltd.)), polycarbonate film, polysulfone (Polysulfone) (Including ether sulfone) film and cycloolefin polymer film are preferable, and particularly preferable from the viewpoints of the objective effects of the present invention being better, manufacturing, cost, transparency, isotropy, adhesiveness, etc. And cellulose ester films such as cellulose triacetate film and cellulose acetate propionate film.

  When producing a cellulose ester film, a method of forming a film after dissolving in an organic halogen compound such as methylene chloride or a solvent such as dioxolane, acetone, methyl acetate, or methyl acetoacetate is generally used. Esters tend to leave the solvent used for dissolution. The elastic modulus of the film tends to decrease due to the influence of the remaining solvent, and plastic deformation is likely to occur, so that the object effect of the present invention is hardly exhibited. For this reason, it is preferable that the transparent film substrate is produced by a melt casting film forming method in the case where the transparent film substrate is a cellulose ester film.

[Melt casting method]
In the present invention, it is preferable to use a cellulose ester film formed by melt casting as a transparent film substrate of a hard coat film.

  More specifically, the heat melting molding method can be classified into a melt extrusion molding method, a press molding method, an inflation method, an injection molding method, a blow molding method, a stretch molding method, and the like. Among these, in order to obtain a hard coat film having excellent mechanical strength and surface accuracy, the melt extrusion method is excellent.

  Here, the film forming material is heated to develop its fluidity and then extruded and formed on a drum or an endless belt, which is included in the melt casting method referred to in the present invention as a melt casting film forming method.

(Cellulose ester)
The cellulose resin is a single or mixed acid ester of cellulose which shows the structure of a cellulose ester and contains at least one of a fatty acyl group and a substituted or unsubstituted aromatic acyl group.

  The cellulose ester constituting the transparent film substrate of the present invention is at least selected from cellulose acetate, cellulose propionate, cellulose butyrate, cellulose acetate propionate, cellulose acetate butyrate, cellulose acetate phthalate, and cellulose phthalate. One type is preferable.

  Among these, particularly preferable cellulose esters include cellulose acetate, cellulose propionate, cellulose butyrate, cellulose acetate propionate, and cellulose acetate butyrate.

  As the substitution degree of the mixed fatty acid ester, more preferable cellulose acetate propionate and lower fatty acid ester of cellulose acetate butyrate have an acyl group having 2 to 4 carbon atoms as a substituent, and the substitution degree of an acetyl group is X. When the substitution degree of the propionyl group or the butyryl group is Y, it is a cellulose resin containing a cellulose ester that simultaneously satisfies the following formulas (I) and (II).

Formula (I) 2.6 ≦ X + Y ≦ 3.0
Formula (II) 0 ≦ X ≦ 2.5
Among these, cellulose acetate propionate is particularly preferably used, and among them, 1.9 ≦ X ≦ 2.5 and 0.1 ≦ Y ≦ 0.9 are preferable. The portion not substituted with the acyl group usually exists as a hydroxyl group. These can be synthesized by known methods.

  Furthermore, the average molecular weight of the cellulose ester is preferably 70000-200000 in terms of number average molecular weight (Mn), more preferably 100000-200000. Further, those having a weight average molecular weight Mw / number average molecular weight Mn ratio of 1.5 to 5.5 are preferably used, particularly preferably 2.0 to 5.0, and further preferably 2.5 to 5.0. More preferably, a cellulose ester of 3.0 to 5.0 is preferably used.

  Since the average molecular weight and molecular weight distribution of the cellulose ester can be measured using high performance liquid chromatography, the number average molecular weight (Mn) and the mass average molecular weight (Mw) can be calculated using this, and the ratio can be calculated.

  The measurement conditions are as follows.

Solvent: Methylene chloride Column: Shodex K806, K805, K803G (Used by connecting three Showa Denko Co., Ltd.)
Column temperature: 25 ° C
Sample concentration: 0.1% by mass
Detector: RI Model 504 (manufactured by GL Sciences)
Pump: L6000 (manufactured by Hitachi, Ltd.)
Flow rate: 1.0ml / min
Calibration curve: Standard polystyrene STK standard polystyrene (manufactured by Tosoh Corporation) Mw = 1,000,000-500 calibration curves with 13 samples were used. The 13 samples are preferably used at approximately equal intervals.

[Raw material cellulose]
The raw material cellulose of the cellulose ester may be wood pulp or cotton linter, and the wood pulp may be softwood or hardwood, but softwood is more preferable. A cotton linter is preferably used from the viewpoint of peelability during film formation. The cellulose ester made from these can be mixed suitably or can be used independently.

  For example, the ratio of cellulose ester derived from cellulose linter: cellulose ester derived from wood pulp (coniferous): cellulose ester derived from wood pulp (hardwood) is 100: 0: 0, 90: 10: 0, 85: 15: 0, 50:50: 0, 20: 80: 0, 10: 90: 0, 0: 100: 0, 0: 0: 100, 80:10:10, 85: 0: 15, 40:30:30.

[Raw polymer shape]
<Particle size / size distribution>
The shape of the raw material polymer including the cellulose resin is preferably in the range of 1 to 10 mm in particle size. This is when the particle size distribution is measured, the average particle size is between 1 and 10 mm, and 90% by mass or more. The particles are in the range of 1-10 mm. The particle size distribution can be measured, for example, using a particle size distribution measuring device such as Nikkiso Co., Ltd. particle size distribution measuring device Microtrac MT3000, Shimadzu Corporation SALD-2000A.

  Moreover, after dispersing a raw material polymer in water, it can be measured by taking a micrograph and analyzing the image.

<Bulk specific gravity>
The bulk specific gravity of the raw material polymer including the cellulose resin can be determined by measuring the mass of the powder filled in a container having a known volume. For example, Tsutsui Rika Instruments Co., Ltd. B. By using a dedicated measuring instrument such as a D powder characteristic measuring instrument, it is possible to measure easily and accurately.

  In the present invention, the bulk specific gravity is preferably in the range of 0.1 to 1.0. B. It means that the loosely packed bulk specific gravity measured using the D powder characteristic measuring device takes a value between 0.1 and 1.0.

  If the bulk specific gravity is less than 0.1, it becomes fluffy, and handling such as transportation and weighing is extremely bad. When it is larger than 1.0, a problem occurs in that the storage silo is in a compacted state and cannot be discharged by bridging. Therefore, it is preferable to be within the above range.

[Drying: Removal of volatile components]
Film formation by the melt casting method is significantly different from the solution casting method, and if a volatile component is present in the material to be cast, it is not preferable from the viewpoint of ensuring the flatness and transparency of the film. This is because transparency deteriorates when volatile components are mixed into the formed film, and when a film is formed by extrusion from a die-slit, the film surface becomes a factor that causes streaking and induces deterioration in flatness. There are things to do. Therefore, when film-forming processing of a film constituent material, it is not preferable that a component that volatilizes in a temperature region lower than the melting temperature for film formation is present from the viewpoint of avoiding the generation of volatile components during heating and melting.

  Examples of the volatile component include moisture absorbed by any of the film constituent materials, or a solvent mixed before the material is purchased or at the time of synthesis, and includes volatilization caused by evaporation, sublimation, or decomposition by heating. The solvent here is different from the solvent for preparing the resin as a solution as a solution casting, and is contained in a trace amount in the film constituting material. Therefore, selection of the film constituent material is important in avoiding the generation of volatile components.

  It is preferable that the film constituent material used for melt casting removes volatile components typified by the moisture and the solvent before film formation or during heating. As this removal method, a so-called known drying method can be applied, and it can be performed by a method such as a heating method, a decompression method, a heating decompression method, etc., or even in an atmosphere in which nitrogen is selected as the inert gas. Good. When these known drying methods are performed, it is preferable in terms of film quality to be performed in a temperature range where the film constituting material does not decompose.

  For example, the water or solvent remaining after removal in the drying step is 20% by mass or less, preferably 10% by mass or less, more preferably 5% by mass or less, and still more preferably, with respect to the total mass of the film constituting material. Is 1% by mass or less.

  The drying temperature at this time is intended to reduce the generation of volatile components by drying before film formation, but as described above, the drying temperature is set to a temperature satisfying the following relationship.

Tmix <Tm−a ≦ Tdry <Tg
(In the formula, Tmix represents the temperature during powder mixing, Tm-a represents the melting point of the stabilizer, Tdry represents the drying temperature of the powder mixture, and Tg represents the glass transition temperature of the cellulose resin.)
A specifically preferable drying temperature is preferably 100 ° C. or higher and Tg or lower of the material to be dried. Including the viewpoint of avoiding fusion between materials, the drying temperature is more preferably 100 ° C. or more and (Tg−5) ° C. or less. Further, the drying is performed at a temperature equal to or higher than the melting point of at least one stabilizer, preferably at a higher temperature.

  A preferable drying time is 0.5 to 24 hours, more preferably 1 to 18 hours, and still more preferably 1.5 to 12 hours.

  The drying process may be separated in two or more stages. For example, the film may be formed through storage of the material in the preliminary drying process and a previous drying process performed immediately before film formation to one week before film formation.

<Granulation>
Prior to producing a transparent film substrate by the melt casting method using the dried film constituent material, the film constituent material can be granulated. The granulation as used herein is a method of extruding and cutting from a screen having a desired shape by applying pressure as it is in a powder, and a method of extruding and cutting from a screen having a desired shape by kneading with a biaxial rotor or the like at a temperature below the melting point. Say etc.

  The shape of the granulated body is not particularly limited, such as a cylindrical shape, a spherical shape, a rectangular parallelepiped shape, and an indefinite shape. Although it depends on the granulation mechanism of the granulator, when measuring the particle size of the granulated material, the total of those smaller than 1 mm and larger than 10 mm is preferably less than 10% by mass, and the screw diameter of the extruder, etc. The size is determined accordingly.

  When granulating, it is also preferable to perform granulation by applying a certain pressure or by applying a temperature below the melting point of the polymer.

  When granulating, additives such as a plasticizer, an antioxidant, a heat stabilizer, a slip agent, etc., which will be described later, can be mixed and granulated.

  As the granulator, a commercially available one can be used. For example, Fuji Paudal Co., Ltd. disk pelleter F-5 to 440, Nippon Steel Works Co., Ltd. large granulator CMP, CIM series, etc., Examples include press pelleters FMP-180N to 800N manufactured by Chiyoda Giken Co., Ltd., and cylindrical granulators FG-250 to 600 manufactured by Fukae Powtex Co., Ltd.

(Additive)
Examples of additives include plasticizers, antioxidants, acid scavengers, light stabilizers, peroxide decomposers, radical scavengers, metal deactivators, ultraviolet absorbers, matting agents, dyes, and pigments. . Moreover, if it has the said function, the additive which is not classified into this is also used.

  Of these, stabilizers such as antioxidants, acid scavengers, and light stabilizers play an important role in terms of function together with the plasticizer. At least one of these stabilizers is preferably dried together with the cellulose resin before heating and melting.

  Antioxidation of film constituent materials is represented by coloring and molecular weight reduction, including decomposition reactions that have not been elucidated, such as capture of acid generated by decomposition, or suppression or prohibition of decomposition reaction caused by radical species due to light or heat. In order to give the function which suppresses the production | generation of the volatile component by the quality change and decomposition | disassembly of material, the above-mentioned stabilizer is used.

  In addition, the presence of the above-mentioned stabilizer suppresses the formation of a colored substance in the visible light region at the time of heating and melting, or the total light transmittance and haze (cloud value) generated by mixing volatile components in the film. It is excellent in that the performance unfavorable as a transparent film base material such as an increase in the temperature can be suppressed or eliminated.

  In addition, since the hard coat film of this invention will affect the display image of a liquid crystal display device when haze (cloud value) exceeds 2%, Preferably it is less than 1%, More preferably, it is less than 0.5%. As an index of colorability, yellowness (yellow index, YI) can be used, preferably 3.0 or less, more preferably 1.0 or less. The hard coat film of the present invention preferably has a transmittance of 85% or more.

  In the above-described film constituent material storage or film forming process, deterioration reactions due to oxygen or moisture in the air may occur simultaneously. In this case, in addition to the stabilizing action of the stabilizer, it is also preferable in the present invention to reduce the humidity and oxygen concentration in the air. Known techniques include use of nitrogen or argon as an inert gas, degassing operation under reduced pressure to vacuum, and operation in a sealed environment, and it is preferable to use at least one of these methods together with the stabilizer. .

  Hereinafter, the additive will be described in more detail.

(Plasticizer)
The addition of a compound known as a plasticizer to the transparent film substrate is preferable from the viewpoint of film modification such as improvement of mechanical properties, imparting flexibility, imparting water absorption resistance, and reducing moisture permeability. Further, in the melt casting method carried out in the present invention, it can be melted at a temperature lower than the glass transition temperature of the cellulose ester used alone by adding a plasticizer, or the viscosity of the film constituting material is lowered at the same heating temperature. it can.

  Here, the melting temperature of the film constituting material means a temperature at which the material is heated to exhibit fluidity.

  As the plasticizer, for example, phosphate ester derivatives and carboxylic acid ester derivatives are preferably used. Further, a polymer obtained by polymerizing an ethylenically unsaturated monomer having a weight average molecular weight of 500 to 10,000 described in JP-A-2003-12859, an acrylic polymer, an acrylic polymer having an aromatic ring in the side chain, or cyclohexyl An acrylic polymer having a group in the side chain is also preferably used.

  Specific plasticizers include phosphate ester plasticizers, ethylene glycol ester plasticizers, glycerin ester plasticizers, diglycerin ester plasticizers (fatty acid esters), polyhydric alcohol ester plasticizers, dicarboxylic acid esters. System plasticizers, polycarboxylic acid ester plasticizers, polymer plasticizers, and the like. Of these, polyhydric alcohol ester plasticizers, dicarboxylic acid ester plasticizers and polycarboxylic acid ester plasticizers are preferred. Further, the plasticizer may be a liquid or a solid, and is preferably colorless due to restrictions on the composition. Thermally, it is preferably stable at a higher temperature, and the decomposition start temperature is preferably 150 ° C. or higher, more preferably 200 ° C. or higher. The addition amount may be as long as it does not adversely affect the optical properties and mechanical properties, and the blending amount is appropriately selected within the range not impairing the object of the present invention, and preferably 0.001 to 50 parts by mass with respect to 100 parts by mass of the cellulose ester. More preferably, it is 0.01-30 mass parts. 0.1-15 mass% is especially preferable.

  Hereinafter, although the specific example of a plasticizer is given, it is not limited to these.

  Phosphate ester plasticizers: specifically, phosphoric acid alkyl esters such as triacetyl phosphate and tributyl phosphate, phosphoric acid cycloalkyl esters such as tricyclobenthyl phosphate and cyclohexyl phosphate, triphenyl phosphate, tricresyl phosphate And phosphoric acid aryl esters such as cresylphenyl phosphate, octyl diphenyl phosphate, diphenyl biphenyl phosphate, trioctyl phosphate, tributyl phosphate, trinaphthyl phosphate, trixylyl phosphate, tris ortho-biphenyl phosphate. These substituents may be the same or different, and may be further substituted. Moreover, the mix of an alkyl group, a cycloalkyl group, and an aryl group may be sufficient, and substituents may couple | bond together by the covalent bond.

  Also alkylene bis (dialkyl phosphate) such as ethylene bis (dimethyl phosphate), butylene bis (diethyl phosphate), alkylene bis (diaryl phosphate) such as ethylene bis (diphenyl phosphate), propylene bis (dinaphthyl phosphate), phenylene bis (dibutyl phosphate) ), Arylene bis (dialkyl phosphate) such as biphenylene bis (dioctyl phosphate), phosphate esters such as arylene bis (diaryl phosphate) such as phenylene bis (diphenyl phosphate) and naphthylene bis (ditoluyl phosphate). These substituents may be the same or different, and may be further substituted. Moreover, the mix of an alkyl group, a cycloalkyl group, and an aryl group may be sufficient, and substituents may couple | bond together by the covalent bond.

  Furthermore, the partial structure of phosphate ester may be part of the polymer, or may be regularly pendant, and also introduced into part of the molecular structure of additives such as antioxidants, acid scavengers, UV absorbers, etc. May be. Among the above-mentioned compounds, phosphoric acid aryl ester and arylene bis (diaryl phosphate) are preferable, and specifically, triphenyl phosphate and phenylene bis (diphenyl phosphate) are preferable.

  Ethylene glycol ester plasticizer: Specifically, ethylene glycol alkyl ester plasticizers such as ethylene glycol diacetate and ethylene glycol dibutyrate, ethylene glycol dicyclopropyl carboxylate, ethylene glycol dicyclohexyl carboxylate and the like Examples include ethylene glycol cycloalkyl ester plasticizers and ethylene glycol aryl ester plasticizers such as ethylene glycol dibenzoate and ethylene glycol di4-methylbenzoate. These alkylate groups, cycloalkylate groups, and arylate groups may be the same or different, and may be further substituted. Moreover, the mix of an alkylate group, a cycloalkylate group, and an arylate group may be sufficient, and these substituents may couple | bond together by the covalent bond. Further, the ethylene glycol part may be substituted, and the ethylene glycol ester partial structure may be part of the polymer or regularly pendant, and may be an antioxidant, an acid scavenger, an ultraviolet absorber, etc. It may be introduced into a part of the molecular structure of the additive.

  Glycerin ester plasticizers: Specifically, glycerol alkyl esters such as triacetin, tributyrin, glycerol diacetate caprylate, glycerol oleate propionate, and glycerin cycloalkyl esters such as glycerol tricyclopropyl carboxylate and glycerol tricyclohexyl carboxylate Glyceryl aryl esters such as glycerin tribenzoate and glycerin 4-methylbenzoate, diglycerin tetraacetylate, diglycerin tetrapropionate, diglycerin acetate tricaprylate, diglycerin alkyl esters such as diglycerin tetralaurate, di Diglycerides such as glycerin tetracyclobutylcarboxylate and diglycerin tetracyclopentylcarboxylate Emissions cycloalkyl esters, diglycerin tetrabenzoate, diglycerin aryl ester such as diglycerin 3-methylbenzoate or the like. These alkylate groups, cycloalkylcarboxylate groups, and arylate groups may be the same or different, and may be further substituted. Moreover, the mix of alkylate group, a cycloalkyl carboxylate group, and an arylate group may be sufficient, and these substituents may couple | bond together by the covalent bond. Furthermore, the glycerin and diglycerin part may be substituted, and the partial structure of the glycerin ester and diglycerin ester may be part of the polymer or regularly pendant, and may be an antioxidant or an acid scavenger. Or may be introduced into a part of the molecular structure of an additive such as an ultraviolet absorber.

  Polyhydric alcohol ester plasticizer: Specific examples include polyhydric alcohol ester plasticizers described in paragraphs [30] to [33] of JP-A No. 2003-12823.

  These alkylate groups, cycloalkylcarboxylate groups, and arylate groups may be the same or different, and may be further substituted. Moreover, the mix of alkylate group, a cycloalkyl carboxylate group, and an arylate group may be sufficient, and these substituents may couple | bond together by the covalent bond. Furthermore, the polyhydric alcohol part may be substituted, and the partial structure of the polyhydric alcohol may be part of the polymer or regularly pendant, and may be an antioxidant, an acid scavenger, an ultraviolet absorber. May be introduced into a part of the molecular structure of the additive.

  Dicarboxylic acid ester plasticizers: Specifically, alkyldocarboxylic acid alkyl ester plasticizers such as didodecyl malonate (C1), dioctyl adipate (C4), dibutyl sebacate (C8), dicyclopentyl succinate, Alkyl dicarboxylic acid cycloalkyl ester plasticizers such as dicyclohexyl adipate, alkyl dicarboxylic acid aryl ester plasticizers such as diphenyl succinate and di4-methylphenyl glutarate, dihexyl-1,4-cyclohexanedicarboxylate, Cycloalkyldicarboxylic acid alkyl ester plasticizers such as didecylbicyclo [2.2.1] heptane-2,3-dicarboxylate, dicyclohexyl-1,2-cyclobutanedicarboxylate, dicyclopropyl-1,2 Cycloalkyldicarboxylic acid cycloalkyl ester plasticizers such as cyclohexyl dicarboxylate, aryl cycloalkyldicarboxylates such as diphenyl-1,1-cyclopropyldicarboxylate, di2-naphthyl-1,4-cyclohexanedicarboxylate Ester plasticizers, aryl dicarboxylic acid alkyl ester plasticizers such as diethyl phthalate, dimethyl phthalate, dioctyl phthalate, dibutyl phthalate and di-2-ethylhexyl phthalate, and aryl dicarboxylic acid cycloalkyls such as dicyclopropyl phthalate and dicyclohexyl phthalate Examples include ester plasticizers and aryl dicarboxylic acid aryl ester plasticizers such as diphenyl phthalate and di4-methylphenyl phthalate. These alkoxy groups and cycloalkoxy groups may be the same or different, may be mono-substituted, and these substituents may be further substituted. The alkyl group and cycloalkyl group may be mixed, or these substituents may be bonded together by a covalent bond. Furthermore, the aromatic ring of phthalic acid may be substituted, and a multimer such as a dimer, trimer or tetramer may be used. Also, the partial structure of phthalate ester may be part of the polymer or regularly pendant to the polymer, and it may be part of the molecular structure of additives such as antioxidants, acid scavengers, and UV absorbers. It may be introduced.

  Polycarboxylic acid ester plasticizers: Specifically, alkyl polycarboxylic acid alkyl ester plastics such as tridodecyl tricarbarate and tributyl-meso-butane-1,2,3,4-tetracarboxylate Agents, alkyl polyvalent carboxylic acid cycloalkyl ester type plasticizers such as tricyclohexyl tricarbarate, tricyclopropyl-2-hydroxy-1,2,3-propanetricarboxylate, triphenyl 2-hydroxy-1,2 Alkyl polycarboxylic acid aryl ester plasticizers such as 1,3-propanetricarboxylate, tetra-3-methylphenyltetrahydrofuran-2,3,4,5-tetracarboxylate, tetrahexyl-1,2,3,4 -Cyclobutane tetracarboxylate, tetrabutyl-1,2, 1,4-cyclopentanetetracarboxylate and other cycloalkyl polycarboxylic acid alkyl ester plasticizers, tetracyclopropyl-1,2,3,4-cyclobutanetetracarboxylate, tricyclohexyl-1,3,5-cyclohexyl Cycloalkyl polycarboxylic acid cycloalkyl ester plasticizers such as tricarboxylate, triphenyl-1,3,5-cyclohexyl tricarboxylate, hexa-4-methylphenyl-1,2,3,4,5,6 -Cycloalkyl polycarboxylic acid aryl ester plasticizers such as cyclohexyl hexacarboxylate, tridodecylbenzene-1,2,4-tricarboxylate, tetraoctylbenzene-1,2,4,5-tetracarboxylate, etc. Aryl polycarboxylic acid Lester ester plasticizer, aryl polyvalent carboxylic acid cycloalkyl ester plasticizer tri such as tricyclopentylbenzene-1,3,5-tricarboxylate, tetracyclohexylbenzene-1,2,3,5-tetracarboxylate Aryl polycarboxylic acid aryl ester-based plasticizers such as phenylbenzene-1,3,5-tetracartoxylate and hexa-4-methylphenylbenzene-1,2,3,4,5,6-hexacarboxylate Can be mentioned. These alkoxy groups and cycloalkoxy groups may be the same or different, may be mono-substituted, and these substituents may be further substituted. The alkyl group and cycloalkyl group may be mixed, or these substituents may be bonded together by a covalent bond. Furthermore, the aromatic ring of phthalic acid may be substituted, and a multimer such as a dimer, trimer or tetramer may be used. Also, the partial structure of phthalate ester may be part of the polymer or regularly pendant to the polymer, and it may be part of the molecular structure of additives such as antioxidants, acid scavengers, and UV absorbers. It may be introduced.

  Polymer plasticizer: Specifically, aliphatic hydrocarbon polymer, alicyclic hydrocarbon polymer, acrylic polymer such as polyethyl acrylate and polymethyl methacrylate, polyvinyl isobutyl ether, poly N-vinyl pyrrolidone, etc. Examples include vinyl polymers, polystyrene, styrene polymers such as poly-4-hydroxystyrene, polybutylene succinate, polyesters such as polyethylene terephthalate and polyethylene naphthalate, polyethers such as polyethylene oxide and polypropylene oxide, polyamides, polyurethanes, and polyureas. It is done. The number average molecular weight is preferably about 1,000 to 500,000, particularly preferably 5,000 to 200,000. If it is 1,000 or less, a problem arises in volatility, and if it exceeds 500,000, the plasticizing ability is lowered, which adversely affects the mechanical properties of the cellulose ester derivative composition. These polymer plasticizers may be a homopolymer composed of one type of repeating unit or a copolymer having a plurality of repeating structures. Two or more of the above polymers may be used in combination, and other plasticizers, antioxidants, acid scavengers, ultraviolet absorbers, slip agents, matting agents, and the like may be included.

  The addition amount of these compounds is preferably used in the range of 0.5% by mass to less than 50% by mass, more preferably 1% by mass to 30% by mass with respect to the resin in which the plasticizer constitutes the film. %, More preferably in the range of 1% by weight to less than 15% by weight.

  Among the plasticizers, it is preferable that no volatile component is generated during heat melting. Specific examples include nonvolatile phosphate esters described in JP-A-6-501040. For example, among arylene bis (diaryl phosphate) esters and the above exemplified compounds, trimethylolpropane tribenzoate is preferable. It is not limited to.

  When the volatile component is caused by thermal decomposition of the plasticizer, the thermal decomposition temperature Td-p (1.0) of the plasticizer is defined as the temperature at which the mass decreases by 1.0% by mass. Higher than that. This is because the amount of the plasticizer added to the cellulose ester is larger than that of other film constituent materials, and the presence of the volatile component has a great influence on the quality of the obtained film. The thermal decomposition temperature Td-p (1.0) can be measured with a commercially available differential thermogravimetric analysis (TG-DTA) apparatus.

  The same applies to stabilizers such as antioxidants, acid scavengers, and light stabilizers, which will be described later, and satisfying the following relationship with the film constituent materials satisfies the physical properties of the obtained transparent film substrate. Preferred above. As a matter of course, when the melting temperature exceeds the decomposition temperature of the plasticizer and stabilizer, the physical properties of the obtained transparent film substrate are lowered.

Tm <Td-p (1.0)
Tm <Td-a (1.0)
(In the formula, Tm is a melting temperature of a film constituting material formed at a temperature of 120 ° C. or more and 250 ° C. or less, Td-p (1.0) is a temperature when 1.0% by mass of the plasticizer is reduced, Td− a (1.0) represents the decomposition temperature when the stabilizer is reduced by 1.0 mass%.)
(Antioxidant)
The antioxidant which is a stabilizer will be described.

  Antioxidants include phenolic antioxidants, phosphorus antioxidants, sulfur antioxidants, heat-resistant processing stabilizers, oxygen scavengers, etc. Among them, phenolic antioxidants, particularly alkyl-substituted phenolic compounds Antioxidants are preferred. By blending these antioxidants, it is possible to prevent coloration or strength reduction of the molded product due to heat, oxidative degradation, or the like during molding without reducing transparency, heat resistance, and the like. These antioxidants can be used alone or in combination of two or more, and the blending amount thereof is appropriately selected within a range not impairing the object of the present invention, but with respect to 100 parts by mass of the cellulose ester. It is preferably 0.001 to 5 parts by mass, more preferably 0.01 to 1 part by mass.

  The hindered phenolic antioxidant compound is a known compound, and is described in, for example, columns 12 to 14 of U.S. Pat. No. 4,839,405, and includes a 2,6-dialkylphenol derivative compound. It is.

  Specific examples of the hindered phenol compound include n-octadecyl = 3- (3,5-di-t-butyl-4-hydroxyphenyl) -propionate, n-octadecyl = 3- (3,5-di-t- Butyl-4-hydroxyphenyl) -acetate, n-octadecyl = 3,5-di-t-butyl-4-hydroxybenzoate, n-hexyl = 3,5-di-t-butyl-4-hydroxyphenylbenzoate, n -Dodecyl = 3,5-di-tert-butyl-4-hydroxyphenylbenzoate, neo-dodecyl = 3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate, dodecyl = β (3,5 -Di-t-butyl-4-hydroxyphenyl) propionate, ethyl = α- (4-hydroxy-3,5-di-t-butylphenyl) isobuty Rate, octadecyl = α- (4-hydroxy-3,5-di-t-butylphenyl) isobutyrate, octadecyl = α- (4-hydroxy-3,5-di-t-butyl-4-hydroxyphenyl) propionate, 2- (n-octylthio) ethyl = 3,5-di-t-butyl-4-hydroxy-benzoate, 2- (n-octylthio) ethyl = 3,5-di-t-butyl-4-hydroxy-phenylacetate 2- (n-octadecylthio) ethyl = 3,5-di-t-butyl-4-hydroxyphenyl acetate, 2- (n-octadecylthio) ethyl = 3,5-di-t-butyl-4-hydroxy -Benzoate, 2- (2-hydroxyethylthio) ethyl = 3,5-di-t-butyl-4-hydroxybenzoate, diethyl glycol = bi Su- (3,5-di-tert-butyl-4-hydroxy-phenyl) propionate, 2- (n-octadecylthio) ethyl = 3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate , Stearamide-N, N-bis- [ethylene = 3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], n-butylimino-N, N-bis- [ethylene = 3- (3 , 5-di-tert-butyl-4-hydroxyphenyl) propionate], 2- (2-stearoyloxyethylthio) ethyl = 3,5-di-tert-butyl-4-hydroxybenzoate, 2- (2-stearoyl) Oxyethylthio) ethyl = 7- (3-methyl-5-tert-butyl-4-hydroxyphenyl) heptanoate, 1,2-propylene glycol = bis- 3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], ethylene glycol = bis- [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], neopentyl Glycol = bis- [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], ethylene glycol = bis- (3,5-di-t-butyl-4-hydroxyphenyl acetate), glycerin -Ln-octadecanoate-2,3-bis- (3,5-di-t-butyl-4-hydroxyphenylacetate), pentaerythritol-tetrakis- [3- (3 ', 5'-di -T-butyl-4'-hydroxyphenyl) propionate], 1,1,1-trimethylolethane-tris- [3- (3,5-di-t-butyl) -4-hydroxyphenyl) propionate], sorbitol hexa- [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], 2-hydroxyethyl = 7- (3-methyl-5-t- Butyl-4-hydroxyphenyl) propionate, 2-stearoyloxyethyl = 7- (3-methyl-5-tert-butyl-4-hydroxyphenyl) heptanoate, 1,6-n-hexanediol-bis [(3 ′, 5'-di-tert-butyl-4-hydroxyphenyl) propionate], pentaerythritol-tetrakis (3,5-di-tert-butyl-4-hydroxyhydrocinnamate). Hindered phenolic antioxidants of the above type are commercially available from Ciba Specialty Chemicals under the trade names “Irganox 1076” and “Irganox 1010”, for example.

  Specific examples of other antioxidants include phosphorus antioxidants such as trisnonylphenyl phosphite, triphenyl phosphite, tris (2,4-di-tert-butylphenyl) phosphite, and dilauryl-3. , 3'-thiodipropionate, dimyristyl-3,3'-thiodipropionate, distearyl-3,3'-thiodipropionate, pentaerythrityltetrakis (3-laurylthiopropionate), etc. System antioxidant, 2-tert-butyl-6- (3-tert-butyl-2-hydroxy-5-methylbenzyl) -4-methylphenyl acrylate, 2- [1- (2-hydroxy-3,5- Di-tert-pentylphenyl) ethyl] -4,6-di-tert-pentylphenyl acrylate 3,4-dihydro-2H-1-benzopyran compound, 3,3′-spirodichroman compound, 1,1-spiroindane compound, morpholine, thiomorpholine, thiomorpholine oxide, described in JP-B-08-27508, Examples include thiomorpholine dioxide, compounds having a piperazine skeleton in the partial structure, oxygen scavengers such as dialkoxybenzene compounds described in JP-A-3-174150, and the like. These antioxidant partial structures may be part of the polymer or regularly pendant to the polymer.

(Acid scavenger)
Since cellulose ester is also decomposed by acid at high temperatures, the transparent film substrate of the present invention preferably contains an acid scavenger as a stabilizer.

  Any useful acid scavenger can be used without limitation as long as it is a compound that reacts with an acid to inactivate the acid. Among them, the epoxy group described in US Pat. No. 4,137,201 is particularly useful. A compound having is preferred. Epoxy compounds as such acid scavengers are known in the art and are derived by condensation of various polyglycol diglycidyl ethers, particularly about 8-40 moles of ethylene oxide per mole of polyglycol. Glycol, diglycidyl ether of glycerol, metal epoxy compounds (such as those conventionally used in and together with vinyl chloride polymer compositions), epoxidized ether condensation products, diphenols of bisphenol A Glycidyl ether (i.e., 4,4'-dihydroxydiphenyldimethylmethane), epoxidized unsaturated fatty acid ester (especially an ester of an alkyl of about 4 to 2 carbon atoms of a fatty acid of 2 to 22 carbon atoms (e.g. butyl Epoxy stearate And epoxidized vegetable oils and other unsaturated natural oils (sometimes these are epoxidized natural glycerides, which can be represented and exemplified by compositions of various epoxidized long chain fatty acid triglycerides and the like (eg, epoxidized soybean oil and the like) Or unsaturated fatty acids, which generally contain 12 to 22 carbon atoms). Moreover, EPON 815C can also be preferably used as a commercially available epoxy group-containing epoxide resin compound.

  Furthermore, examples of acid scavengers that can be used other than the above include oxetane compounds, oxazoline compounds, organic earth salts of alkaline earth metals and acetylacetonate complexes, and paragraphs 68 to 105 of JP-A-5-194788. Is included.

  In addition, although an acid scavenger may be called an acid scavenger, an acid capture agent, an acid catcher etc., in this invention, it can use without a difference by these names.

(Light stabilizer)
Transparent film substrates include hindered amine light stabilizer (HALS) compounds as stabilizers for external light and light from backlights of liquid crystal displays, which are known compounds, for example, US Pat. No. 5,619,956 and US Pat. No. 4,839,405, columns 3-5, 2,2,6,6-tetraalkylpiperidine. Compounds, or their acid addition salts or complexes of them with metal compounds are included.

  Specific examples of hindered amine light stabilizer compounds include 4-hydroxy-2,2,6,6-tetramethylpiperidine, 1-allyl-4-hydroxy-2,2,6,6-tetramethylpiperidine, 1-benzyl. -4-hydroxy-2,2,6,6-tetramethylpiperidine, 1- (4-tert-butyl-2-butenyl) -4-hydroxy-2,2,6,6-tetramethylpiperidine, 4-stearoyl Oxy-2,2,6,6-tetramethylpiperidine, 1-ethyl-4-salicyloyloxy-2,2,6,6-tetramethylpiperidine, 4-methacryloyloxy-1,2,2,6 6-pentamethylpiperidine, 1,2,2,6,6-pentamethylpiperidin-4-yl-β (3,5-di-t-butyl-4-hydroxyphenyl) -propionate, -Benzyl-2,2,6,6-tetramethyl-4-piperidinyl maleate, (di-2,2,6,6-tetramethylpiperidin-4-yl) -adipate, (di- 2,2,6,6-tetramethylpiperidin-4-yl) -sebacate, (di-1,2,3,6-tetramethyl-2,6-diethyl-piperidin-4-yl) -sebacate, (di -1-allyl-2,2,6,6-tetramethyl-piperidin-4-yl) -phthalate, 1-acetyl-2,2,6,6-tetramethylpiperidin-4-yl-acetate, trimellitic acid- Tri- (2,2,6,6-tetramethylpiperidin-4-yl) ester, 1-acryloyl-4-benzyloxy-2,2,6,6-tetramethylpiperidine, dibutyl-malonic acid-di -(1,2,2,6,6-pentamethyl-piperidin-4-yl) -ester, dibenzyl-malonic acid-di- (1,2,3,6-tetramethyl-2,6-diethyl-piperidine- 4-yl) -ester, dimethyl-bis- (2,2,6,6-tetramethylpiperidine-4-oxy) -silane, tris- (1-propyl-2,2,6,6-tetramethylpiperidine- 4-yl) -phosphite, tris- (1-propyl-2,2,6,6-tetramethylpiperidin-4-yl) -phosphate, N, N′-bis- (2,2,6,6- Tetramethylpiperidin-4-yl) -hexamethylene-1,6-diamine, N, N'-bis- (2,2,6,6-tetramethylpiperidin-4-yl) -hexamethylene-1,6- Diacetamide, 1-acetyl -4- (N-cyclohexylacetamide) -2,2,6,6-tetramethyl-piperidine, 4-benzylamino-2,2,6,6-tetramethylpiperidine, N, N'-bis- (2, 2,6,6-tetramethylpiperidin-4-yl) -N, N'-dibutyl-adipamide, N, N'-bis- (2,2,6,6-tetramethylpiperidin-4-yl) -N , N'-dicyclohexyl- (2-hydroxypropylene), N, N'-bis- (2,2,6,6-tetramethylpiperidin-4-yl) -p-xylylene-diamine, 4- (bis-2 -Hydroxyethyl) -amino-1,2,2,6,6-pentamethylpiperidine, 4-methacrylamide-1,2,2,6,6-pentamethylpiperidine, α-cyano-β-methyl-β- [N- (2,2 6,6-tetramethyl-piperidin-4-yl)] - amino - and methyl acrylate and the like.

  At least one or more stabilizers in the film-forming material can be selected, and the amount added is preferably 0.001% by mass to 5% by mass with respect to the mass of the cellulose ester. More preferably, it is 0.005 mass% or more and 3 mass% or less, More preferably, it is 0.01 mass% or more and 0.8 mass% or less.

(UV absorber)
When the hard coat film of the present invention is used as a polarizer protective film used on the viewing side with respect to the liquid crystal cell, it is preferable to further contain an ultraviolet absorber. The ultraviolet absorber is a material having an effect of preventing the material constituting the film from being decomposed by ultraviolet rays in an environment used after production. Cellulose ester itself is a material that is relatively resistant to ultraviolet rays, but other additives may be compounds that are weak against ultraviolet rays, and polarizers and liquid crystal cells are also vulnerable to ultraviolet rays. In addition, it is preferable that at least the polarizer protective film on the side exposed to external light and the polarizer protective film on the side on which the backlight of the liquid crystal display is incident contain an ultraviolet absorber.

  As such an ultraviolet absorber, from the viewpoint of preventing deterioration of a polarizer and a display device with respect to ultraviolet rays, the ultraviolet absorber has an excellent ability to absorb ultraviolet rays having a wavelength of 370 nm or less, and from the viewpoint of liquid crystal display properties, visible light having a wavelength of 400 nm or more. Those that absorb less are preferred. Examples include oxybenzophenone compounds, benzotriazole compounds, triazine compounds, salicylic acid ester compounds, benzophenone compounds, cyanoacrylate compounds, nickel complex compounds, and the like. Triazole compounds are preferable, and benzotriazole compounds are particularly preferable. Moreover, you may use the ultraviolet absorber of Unexamined-Japanese-Patent No. 10-182621, Unexamined-Japanese-Patent No. 8-337574, and the polymeric ultraviolet absorber of Unexamined-Japanese-Patent No. 6-148430.

  Specific examples of useful benzotriazole ultraviolet absorbers include 2- (2′-hydroxy-5′-methylphenyl) benzotriazole, 2- (2′-hydroxy-3 ′, 5′-di-tert-butylphenyl). ) Benzotriazole, 2- (2'-hydroxy-3'-tert-butyl-5'-methylphenyl) benzotriazole, 2- (2'-hydroxy-3 ', 5'-di-tert-butylphenyl)- 5-chlorobenzotriazole, 2- (2′-hydroxy-3 ′-(3 ″, 4 ″, 5 ″, 6 ″ -tetrahydrophthalimidomethyl) -5′-methylphenyl) benzotriazole, 2,2-methylenebis ( 4- (1,1,3,3-tetramethylbutyl) -6- (2H-benzotriazol-2-yl) phenol), 2- (2'-hydro Cis-3'-tert-butyl-5'-methylphenyl) -5-chlorobenzotriazole, 2- (2H-benzotriazol-2-yl) -6- (linear and side chain dodecyl) -4-methylphenol Octyl-3- [3-tert-butyl-4-hydroxy-5- (chloro-2H-benzotriazol-2-yl) phenyl] propionate and 2-ethylhexyl-3- [3-tert-butyl-4-hydroxy Examples include, but are not limited to, a mixture of -5- (5-chloro-2H-benzotriazol-2-yl) phenyl] propionate.

  As commercially available products, TINUVIN 109, TINUVIN 171, TINUVIN 234, and TINUVIN 360 (all manufactured by Ciba Japan) may be used.

  Specific examples of benzophenone compounds include 2,4-dihydroxybenzophenone, 2,2'-dihydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxy-5-sulfobenzophenone, bis (2-methoxy-4-hydroxy- 5-benzoylphenyl) methane and the like can be mentioned, but are not limited thereto.

  In the present invention, the ultraviolet absorber is preferably added in an amount of 0.1 to 20% by mass, more preferably 0.5 to 10% by mass, and further preferably 1 to 5% by mass. Two or more of these may be used in combination.

(Matting agent)
The transparent film substrate can be added with fine particles such as a matting agent in order to impart slipperiness, and examples of the fine particles include inorganic compound fine particles and organic compound fine particles. The matting agent is preferably as fine as possible. Examples of the fine particles include silicon dioxide, titanium dioxide, aluminum oxide, zirconium oxide, calcium carbonate, kaolin, talc, calcined calcium silicate, hydrated calcium silicate, aluminum silicate, Examples thereof include inorganic fine particles such as magnesium silicate and calcium phosphate, and crosslinked polymer fine particles. Among these, silicon dioxide is preferable because it can reduce the haze of the film. In many cases, fine particles such as silicon dioxide are surface-treated with an organic material, but such a material is preferable because it can reduce the haze of the film.

  Preferred organic substances for the surface treatment include halosilanes, alkoxysilanes, silazane, siloxane and the like. The larger the average particle size of the fine particles, the greater the sliding effect, and the smaller the average particle size, the better the transparency. The average particle size of the secondary particles of the fine particles is in the range of 0.05 to 1.0 μm. The average particle size of secondary particles of the fine particles is preferably 5 to 50 nm, more preferably 7 to 14 nm. These fine particles are preferably used in the cellulose ester film in order to generate irregularities of 0.01 to 1.0 μm on the surface of the cellulose ester film. The content of the fine particles in the cellulose ester is preferably 0.005 to 0.3% by mass with respect to the cellulose ester.

  Examples of the fine particles of silicon dioxide include Aerosil 200, 200V, 300, R972, R972V, R974, R202, R812, OX50, TT600 manufactured by Nippon Aerosil Co., Ltd., preferably Aerosil 200V, R972. , R972V, R974, R202, R812. Two or more kinds of these fine particles may be used in combination. When using 2 or more types together, it can mix and use in arbitrary ratios. In this case, fine particles having different average particle sizes and materials, for example, Aerosil 200V and R972V can be used in a mass ratio of 0.1: 99.9 to 99.9: 0.1.

  The presence of fine particles in the film used as the matting agent can be used for another purpose to improve the strength of the film. In addition, the presence of the fine particles in the film can improve the orientation of the cellulose ester constituting the transparent film substrate of the present invention.

(Film formation)
For the transparent film substrate, for example, a mixture of a cellulose ester and an additive is hot-air dried or vacuum dried, then melt-extruded, extruded into a film form from a T-die, and taken up by a roll adjusted to a temperature of 50 to 150 ° C. Is preferred. At this time, nipping with two rolls is preferable from the viewpoint of improving flatness.

  For melt extrusion, a single screw extruder, a twin screw extruder, or a single screw extruder may be connected downstream of the twin screw extruder, but a twin screw extruder is used from the viewpoint of uniformly dispersing the aforementioned additives. It is preferable. Furthermore, it is preferable to replace or depressurize the raw material supply and melting processes such as the raw material tank, the raw material charging section, and the inside of the extruder with an inert gas such as nitrogen gas.

  The temperature during the melt extrusion is preferably in the range of Tg or more and Tg + 100 ° C. or less. Furthermore, it is preferable that it is the range of Tg + 10 degreeC or more and Tg + 90 degreeC or less.

  When a polarizing plate is produced using the transparent film substrate of the present invention as a polarizing plate protective film, the cellulose ester film is particularly preferably a film stretched in the width direction or the film forming direction.

  The unstretched film peeled from the cooling roll described above is brought into the glass transition temperature (Tg) -50 ° C. to Tg + 100 ° C. of the cellulose ester via a plurality of roll groups and / or a heating device such as an infrared heater. It is preferable to heat and stretch in one or more stages. Next, it is preferable that the cellulose ester film stretched in the longitudinal direction obtained as described above is transversely stretched within a temperature range of Tg-50 ° C to Tg + 100 ° C and then heat-set.

  In the case of transverse stretching, it is preferable to perform transverse stretching while sequentially raising the temperature difference in the range of 1 to 50 ° C. in a stretching region divided into two or more, because the distribution of physical properties in the width direction can be reduced. Further, after the transverse stretching, it is preferable that the film is held at a temperature of Tg-40 ° C. or higher at a temperature equal to or lower than the final transverse stretching temperature for 0.01 to 5 minutes because the distribution of physical properties in the width direction can be further reduced.

  In the heat setting, heat setting is usually performed for 0.5 to 300 seconds at a temperature higher than the final transverse stretching temperature and within a temperature range of Tg-20 ° C or lower. At this time, it is preferable to heat-fix while sequentially raising the temperature difference in the range of 1 to 100 ° C. in the region divided into two or more.

  The heat-set film is usually cooled to Tg or less, and clip holding portions at both ends of the film are cut and wound. At this time, it is preferable to perform a relaxation treatment of 0.1 to 10% in the horizontal direction and / or the vertical direction within the temperature range of the final heat setting temperature or lower and Tg or higher. In addition, it is preferable that the cooling is gradually performed from the final heat setting temperature to Tg at a cooling rate of 100 ° C. or less per second. Means for cooling and relaxation treatment are not particularly limited, and can be performed by a conventionally known means. In particular, it is preferable to carry out these treatments while sequentially cooling in a plurality of temperature ranges from the viewpoint of improving the dimensional stability of the film. The cooling rate is a value obtained by (T1−Tg) / t, where T1 is the final heat setting temperature and t is the time until the film reaches Tg from the final heat setting temperature.

  More optimal conditions of these heat setting conditions, cooling, and relaxation treatment conditions vary depending on the cellulose ester constituting the film, so the physical properties of the obtained biaxially stretched film should be measured and adjusted appropriately to have desirable characteristics. It may be determined by.

  In the film forming process, the clip gripping portions at both ends of the cut film are pulverized or granulated as necessary, and then used as a film material of the same product type or as a film material of a different product type. It may be reused.

  A cellulose ester film having a laminated structure can also be produced by co-extruding compositions containing cellulose resins having different additive concentrations such as the above-mentioned plasticizer, ultraviolet absorber and matting agent. For example, a cellulose ester film having a structure of skin layer / core layer / skin layer can be produced. For example, the matting agent can be contained in the skin layer in a large amount or only in the skin layer. The plasticizer and the ultraviolet absorber can be contained in the core layer more than the skin layer, and may be contained only in the core layer. In addition, the type of plasticizer and ultraviolet absorber can be changed between the core layer and the skin layer. For example, the skin layer contains a low-volatile plasticizer and / or an ultraviolet absorber, and the core layer has excellent plasticity. It is also possible to add a plasticizer or an ultraviolet absorber excellent in ultraviolet absorption. The Tg of the skin layer and the core layer may be different, and the Tg of the core layer is preferably lower than the Tg of the skin layer. Also, the viscosity of the melt containing the cellulose ester during melt casting may be different between the skin layer and the core layer, and the viscosity of the skin layer> the viscosity of the core layer or the viscosity of the core layer ≧ the viscosity of the skin layer may be used.

  The hard coat film of the present invention is preferably used for a polarizing plate protective film. When using as a polarizing plate protective film, the manufacturing method of a polarizing plate is not specifically limited, It can manufacture by a general method. The obtained hard coat film was treated with an alkali, and a polyvinyl alcohol film was immersed and stretched in an iodine solution, and a polarizer protective film was attached to both sides of the polarizer using a completely saponified polyvinyl alcohol aqueous solution on both sides of the polarizer. There is a method of matching, and it is preferable that the hard coat film of the present invention is directly bonded to the polarizer on at least one side.

  The transparent film substrate preferably has a surface roughness Ra of 1 μm or less. When Ra is larger than 1 μm, when the above-described various functional layers are provided, the surface may become uneven or remain as convex defects, and smoothness and gloss may be impaired. In order to reduce Ra to 1 μm or less, the surface of the take-up roll and the drawing roll immediately after melt extrusion is made into a mirror surface, or the surface of the take-up roll immediately after being taken by the roll is nipped between the mirror surface rolls, This is achieved by appropriately selecting the magnification and the stretching speed. It is also effective to reduce Ra by sharpening the lip edge of the melt-extrusion die or mirroring the surface in contact with the molten resin inside the die.

  When the hard coat film of the present invention is a polarizing plate protective film, the thickness of the protective film is preferably 10 to 500 μm. In particular, it is preferably 20 μm or more, and more preferably 35 μm or more. Moreover, 150 micrometers or less, Furthermore 120 micrometers or less are preferable. Most preferably, it is 25 or more and 90 micrometers. If the hard coat film is thicker than the above region, the polarizing plate after polarizing plate processing becomes too thick, so that it is not suitable for the purpose of thin and light in liquid crystal displays used for notebook personal computers and mobile electronic devices. On the other hand, if it is thinner than the above-mentioned region, it is not preferable because it becomes difficult to develop retardation, the moisture permeability of the film becomes high, and the ability to protect the polarizer from humidity decreases.

"Polarizer"
A polarizing plate using the hard coat film of the present invention will be described.

  The polarizing plate can be produced by a general method. The back surface side of the hard coat film of the present invention is subjected to alkali saponification treatment, and a completely hardened polyvinyl alcohol aqueous solution is used on at least one surface of a polarizing film prepared by immersing and stretching the treated hard coat film in an iodine solution. It is preferable to bond them together. The hard coat film may be used on the other surface, or another polarizing plate protective film may be used. With respect to the hard coat film of the present invention, the polarizing plate protective film used on the other surface has an in-plane retardation Ro of 590 nm, an optical compensation film having a phase difference of 20 to 70 nm and Rt of 100 to 400 nm. It is preferable to use a retardation film. These can be prepared, for example, by the methods described in JP-A No. 2002-71957 and Japanese Patent Application No. 2002-155395. Alternatively, it is preferable to use a polarizing plate protective film that also serves as an optical compensation film having an optically anisotropic layer formed by aligning a liquid crystal compound such as a discotic liquid crystal. For example, the optically anisotropic layer can be formed by the method described in JP-A-2003-98348. Alternatively, a non-oriented film having a retardation Ro of 590 nm of 0 to 5 nm and an Rt of -20 to +20 nm described in JP-A No. 2003-12859 is also preferably used.

  By using in combination with the hard coat film of the present invention, a polarizing plate having excellent flatness and a stable viewing angle expansion effect can be obtained.

  As a polarizing plate protective film used on the back side, as a commercially available cellulose ester film, KC8UX2MW, KC4UX, KC5UX, KC4UY, KC8UY, KC12UR, KC4UEW, KC8UCR-3, KC8UCR-4, KC8UCR-5, KC4FR-1, KC4F-1, -2, KC8UE, KC4UE (manufactured by Konica Minolta Opto Co., Ltd.) and the like are preferably used.

  The polarizing film, which is the main component of the polarizing plate, is an element that transmits only light having a polarization plane in a certain direction. A typical polarizing film known at present is a polyvinyl alcohol polarizing film, which is a polyvinyl alcohol film. There are ones in which iodine is dyed on a system film and ones in which a dichroic dye is dyed, but it is not limited to this. As the polarizing film, a polyvinyl alcohol aqueous solution is formed and dyed by uniaxially stretching or dyed, or uniaxially stretched after dyeing, and then preferably subjected to a durability treatment with a boron compound. A polarizing film having a thickness of 5 to 30 μm, preferably 8 to 15 μm, is preferably used. On the surface of the polarizing film, one side of the hard coat film of the present invention is bonded to form a polarizing plate. It is preferably bonded with an aqueous adhesive mainly composed of completely saponified polyvinyl alcohol or the like.

<Display device>
By incorporating a polarizing plate produced using the hard coat film of the present invention into a display device, the display device of the present invention having various visibility can be produced.

  The hard coat film of the present invention is incorporated in the polarizing plate, and is a reflective type, transmissive type, transflective type LCD or TN type, STN type, OCB type, HAN type, VA type (PVA type, MVA type), IPS type, It is preferably used in various drive-type liquid crystal display devices such as OCB type.

  In addition, the hard coat film of the present invention is excellent in scratch resistance and flatness, and is preferably used in various display devices such as a plasma display, a field emission display, an organic EL display, an inorganic EL display, and electronic paper.

  EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.

Example 1
[Production of cellulose ester film]
(Synthesis of cellulose ester C1)
With reference to Example B of JP-T-6-501040, the amount of propionic acid and acetic acid was adjusted to synthesize cellulose ester C1 with the acetyl group substitution degree and propionyl group substitution degree adjusted as follows. .

C1: acetyl group substitution degree 1.9, propionyl group substitution degree 0.7, total acyl group substitution degree 2.60
The substitution degree of the obtained cellulose ester was calculated based on ASTM-D817-96. The weight average molecular weight of the cellulose ester C1 was 130,000 as a result of measurement using the high performance liquid chromatography.

(Preparation of cellulose ester film 1)
Cellulose ester film 1 was produced by melt casting with the following composition.

<Cellulose ester film 1 composition>
Cellulose ester: C1 94 parts by mass Plasticizer: Glycerin tribenzoate 5 parts by mass Irganox 1010 (manufactured by Ciba Japan) 0.5 part by mass Irgafos P-EPG (manufactured by Ciba Japan) 0.3 part by mass HP-136 ( 0.2 parts by mass The above cellulose ester was dried under reduced pressure at 70 ° C. for 3 hours and cooled to room temperature, and then each additive was mixed.

  The above mixture was formed into a film by a manufacturing apparatus using an elastic touch roll. In a nitrogen atmosphere, it was melted at 240 ° C., extruded from the casting die onto the first cooling roll, and molded by pressing the film between the first cooling roll and the touch roll. Further, silica particles (manufactured by Nippon Aerosil Co., Ltd.) were added as a slip agent from the hopper opening in the middle of the extruder so as to be 0.1 part by mass.

  The heat bolt was adjusted so that the gap width of the casting die was 0.5 mm within 30 mm from the end in the width direction of the film and 1 mm at other locations. As a touch roll, 80 degreeC water was poured as cooling water in the inside.

  The circumference of the first cooling roller from the position P1 where the resin extruded from the casting die contacts the first cooling roll to the position P2 at the upstream end in the first cooling roll rotation direction of the nip between the first cooling roll and the touch roll. The length L along the surface was set to 20 mm. Thereafter, the touch roll was separated from the first cooling roll, and the temperature T of the melted part immediately before being sandwiched in the nip between the first cooling roll and the touch roll was measured. The temperature T of the melted part immediately before being squeezed by the nip between the first cooling roll and the touch roll is a thermometer (HA-200E manufactured by Anritsu Keiki Co., Ltd.) at a position 1 mm upstream from the nip upstream end P2. It was measured by. As a result of the measurement, the temperature T was 141 ° C. The linear pressure of the touch roll against the first cooling roll was 14.7 N / cm. Furthermore, after being introduced into a tenter and stretched 1.3 times at 160 ° C in the width direction, it was cooled to 30 ° C while relaxing 3% in the width direction, then released from the clip, the clip gripping part was cut off, and both ends of the film Was subjected to a knurling process with a width of 10 mm and a height of 5 μm, and wound on a winding core with a winding tension of 220 N / m and a taper of 40%. The winding core had an inner diameter of 152 mm, an outer diameter of 165 to 180 mm, and a length of 1550 mm. A prepreg resin obtained by impregnating glass fibers and carbon fibers with an epoxy resin was used as the core material for the core. The surface of the core was coated with an epoxy conductive resin, the surface was polished, and the surface roughness Ra was finished to 0.3 μm. In addition, the film thickness was 80 micrometers and the winding length was 3500 m, and the cellulose-ester film 1 was produced.

[Production of hard coat film]
(Preparation of hard coat film 1)
Using the cellulose ester film 1 described above, a hard coat film 1 was prepared according to the following procedure.

On the cellulose ester film 1, the following hard coat layer coating composition 1 is filtered through a polypropylene filter having a pore size of 0.4 μm to prepare a hard coat layer coating solution, and a microgravure coater using the apparatus of FIG. After irradiating at 70 ° C. and purging with nitrogen so that the atmosphere has an oxygen concentration of 1.0% by volume or less, the illuminance of the irradiated part is 100 mW / cm ² and the irradiation amount is 0 with an ultraviolet lamp. After the coating layer was cured at 0.1 J / cm ² to form a hard coat layer with a dry film thickness of 9 μm, the hard coat layer was subsequently applied so that the following back coat layer coating composition 1 had a wet film thickness of 10 μm. The surface opposite to the surface was coated with an extrusion coater and dried to produce a hard coat film 1 and wound up.

  The hard coat film 1 passed through the heat treatment zone 7 of FIG. 1, but was not subjected to the heat treatment (room temperature: 25 ° C.), and the conveyance tension was also appropriate (200 N / m).

<Hard coat layer composition 1>
(Preparation of fluorine-siloxane graft polymer 1)
Hereinafter, commercially available product names of materials used for preparing the fluorine-siloxane graft polymer 1 are shown.

Cefalcoat CF-803 (hydroxyl value 60, number average molecular weight 15,000; manufactured by Central Glass Co., Ltd.)
Silaplane FM-0721 (number average molecular weight 5,000; manufactured by Chisso Corporation)
Perbutyl O (t-butylperoxy-2-ethylhexanoate; manufactured by NOF Corporation)
Sumidur N3200 (hexuremethylene diisocyanate biuret type prepolymer; manufactured by Sumitomo Bayer Urethane Co., Ltd.)
[Synthesis of radical polymerizable fluororesin (A)]
In a glass reactor equipped with a mechanical stirrer, thermometer, condenser and dry nitrogen gas inlet, cefal coat CF-803 (1554 parts by mass), xylene (233 parts by mass), and 2-isocyanatoethyl methacrylate (6 3 parts by mass) and heated to 80 ° C. in a dry nitrogen atmosphere. After reacting at 80 ° C. for 2 hours and confirming that the absorption of isocyanate disappeared by the infrared absorption spectrum of the sample, the reaction mixture was taken out and 50% by mass of radically polymerizable fluororesin (A) via a urethane bond. Got.

  Next, the above synthesized radical polymerizable fluororesin (A) (26.1 parts by mass), xylene (19.5 parts) were added to a glass reactor equipped with a mechanical stirrer, a thermometer, a condenser and a dry nitrogen gas inlet. Parts by weight), n-butyl acetate (16.3 parts by weight), methyl methacrylate (2.4 parts by weight), n-butyl methacrylate (1.8 parts by weight), lauryl methacrylate (1.8 parts by weight), 2- Hydroxyethyl methacrylate (1.8 parts by mass), FM-0721 (5.2 parts by mass), and perbutyl O (0.1 parts by mass) were added and heated to 90 ° C. in a nitrogen atmosphere. Held for hours. Perbutyl O (0.1 part) was added, and the solution was further maintained at 90 ° C. for 5 hours to obtain a 35 mass% fluorine-siloxane graft polymer 1 solution having a weight average molecular weight of 171,000.

  The weight average molecular weight was determined by GPC. The mass% of the fluorine-siloxane graft polymer 1 was determined by HPLC (liquid chromatography).

  The following materials were stirred and mixed to obtain hard coat layer coating composition 1.

(Polyfunctional acrylate)
Pentaerythritol triacrylate 20 parts by mass Pentaerythritol tetraacrylate 50 parts by mass Dipentaerythritol hexaacrylate 30 parts by mass Dipentaerythritol pentaacrylate 30 parts by mass (photopolymerization initiator)
Irgacure 184 (Ciba Japan) 5 parts by mass Irgacure 907 (Ciba Japan) 10 parts by mass (additive)
Fluorine-siloxane graft polymer 1 (35% by mass) 5 parts by mass Pentaerythritol tetrakis (3-mercaptobutyrate) 2.5 parts by mass (solvent)
Propylene glycol monomethyl ether 10 parts by weight Methyl acetate 20 parts by weight Acetone 20 parts by weight Methyl ethyl ketone 60 parts by weight Cyclohexanone 20 parts by weight <Backcoat layer coating composition 1>
Diacetyl cellulose 0.6 parts by weight Acetone 35 parts by weight Methyl ethyl ketone 35 parts by weight Methanol 35 parts by weight A 2% methanol dispersion of silica particles (KE-P30, manufactured by Nippon Shokubai Co., Ltd.)
16 parts by mass [Production of hard coat films 2 to 5]
Similarly to the hard coat film 1, under the conditions described in Table 1, the heat treatment conditions and tension in the heat treatment zone 7 of FIG. 1 were changed to produce hard coat film films 2 to 5.

[Preparation of hard coat films 6-20]
In the heat treatment chamber A of FIG. 2, the heat treatment temperature, the heat treatment time, the temperature rise temperature, and the temperature fall temperature of the hard coat film produced and wound in the same manner as the hard coat film 1 are changed as shown in Table 1. Hard coat films 6 to 20 were produced.

[Production of hard coat films 21 and 22]
The heat treatment is performed in the heat treatment zone 7 of FIG. 1 in the same manner as the hard coat film 3, and then the heat treatment is performed in the heat treatment chamber A of FIG. Produced.

[Preparation of hard coat film 23]
Instead of the heat treatment zone 7 in FIG. 1, the film is conveyed using a tenter device capable of heat treatment shown in FIG. 3, and stretched by 0.1% in the width direction of the film. Heat treatment was performed under conditions to produce a hard coat film 23.

  After applying the hard coat layer to the hard coat films 1 to 23 produced as described above, it was determined by visual inspection whether the cured film was curled. As a result, no curl was observed in any of the films.

<< Evaluation of hard coat film >>
The following evaluation was implemented using produced hard coat films 1-23.

(Scratch resistance)
A load of 200 g / cm ² was applied to # 0000 steel wool (SW) in an environment of 23 ° C. and 55% RH on the hard coat film, and the number of scratches per 1 cm width when 10 reciprocations were measured. In addition, the number of scratches is measured at a place where the number of scratches is the largest among the portions where the load is applied. If it is 10 / cm or less, there is no practical problem, but 5 / cm or less is preferable, and 3 / cm or less is more preferable.

(Evaluation of blocking properties)
The degree of occurrence of blocking when the hard coat film was unwound from the wound roll was visually evaluated according to the following criteria.

◎: No blocking ○: There is no trace or deformation on the sample to the extent that a light peeling sound is made Δ: There is no deformation, but a trace remains on the sample ×: There is deformation and irregularities remain on the sample Evaluation results are shown in Table 2 below .

  From the results in Table 2, it can be seen that the hard coat film produced by the production method of the present invention is excellent in curling resistance, and further excellent in scratch resistance (high hardness) and blocking property. Among them, the heating temperature after light irradiation is increased to 60 ° C. or higher, 80 ° C. or higher, and further 120 ° C. or higher, and in the heat treatment process, a tension of 250 N / m to 500 N / m is applied in the conveying direction. Thus, it can be seen that the above-described particularly excellent effect is exhibited.

Example 2
[Preparation of antireflection films 1 to 23]
Next, the following high refractive index layer coating solution 1 was applied onto the hard coat films 1 to 23 produced in Example 1, and further the low refractive index layer coating solution 1 was applied thereon and dried, followed by 120 ° C. And then cured by irradiating with ultraviolet rays, and a high refractive index layer having a thickness of 120 nm and a low refractive index layer having a thickness of 85 nm are provided and wound into a roll, and then at 60 ° C. for 5 days. Anti-reflection films 1 to 23 were produced by heat aging treatment. The refractive index of the high refractive index layer was 1.60, and the refractive index of the low refractive index layer was 1.38. The center line average roughness (Ra) of the surface of the low refractive index layer was 100 nm or less and was smooth.

(High refractive index layer coating solution 1)
Tetra (n) butoxytitanium 3 parts by weight Conductive ITO fine particles (ELCOM V2504, ITO sol, solid content 20% by weight, manufactured by Catalytic Chemical) 200 parts by weight Dipentaerythritol hexaacrylate (matrix) 50 parts by weight Irgacure 184 (initiating photopolymerization) Agent) 3 parts by mass γ-methacryloxypropylmethoxysilane (KBM503 manufactured by Shin-Etsu Chemical Co., Ltd.)
8 parts by mass Poly-n-butyl methacrylate (matrix) 5 parts by mass Propylene glycol monomethyl ether (PGME) 720 parts by mass Isopropyl alcohol 1470 parts by mass Methyl ethyl ketone (MEK) 250 parts by mass <Preparation of tetraethoxysilane hydrolyzate A>
Tetraethoxysilane hydrolyzate A was prepared by mixing 58 g of tetraethoxysilane and 114 g of ethanol and adding 60 g of an acetic acid aqueous solution (1%) thereto, followed by stirring at 25 ° C. for 1 hour.
(Low refractive index layer coating solution 1)
Tetraethoxysilane hydrolyzate A 59.5 parts by mass The following silica-based fine particles P-1 35 parts by mass γ-methacryloxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., KBM503)
5 parts by mass FZ-2222 (Nihon Unicar, 10% propylene glycol monomethyl ether solution) 0.5 parts by mass Isopropyl alcohol 500 parts by mass Propylene glycol monomethyl ether (PGME) 300 parts by mass Methyl ethyl ketone (MEK) 100 parts by mass <Silica-based fine particles Preparation of P-1>
A mixture of 100 g of silica sol having an average particle diameter of 5 nm and a SiO ₂ concentration of 20% by mass and 1900 g of pure water was heated to 80 ° C. The pH of this reaction mother liquor was 10.5, and 9000 g of 0.98 mass% sodium silicate aqueous solution as SiO ₂ and 9000 g of 1.02 mass% sodium aluminate aqueous solution as Al ₂ O ₃ were simultaneously added to the mother liquor. did. Meanwhile, the temperature of the reaction solution was kept at 80 ° C. The pH of the reaction solution rose to 12.5 immediately after the addition and hardly changed thereafter. After completion of the addition, the reaction solution was cooled to room temperature and washed with an ultrafiltration membrane to prepare a SiO ₂ .Al ₂ O ₃ core particle dispersion having a solid content concentration of 20% by mass. (Process (a))
1700 g of pure water is added to 500 g of this core particle dispersion and heated to 98 ° C., and while maintaining this temperature, a silicate solution (SiO ₂₎ obtained by dealkalizing a sodium silicate aqueous solution with a cation exchange resin. A dispersion of core particles in which 3000 g (concentration of 3.5% by mass) was added to form a first silica coating layer was obtained. (Process (b))
Next, 1125 g of pure water is added to 500 g of the core particle dispersion liquid that has been washed with an ultrafiltration membrane to form a first silica coating layer having a solid content concentration of 13% by mass, and concentrated hydrochloric acid (35.5%) is further added dropwise. The pH was adjusted to 1.0 and dealumination was performed. Next, the aluminum salt dissolved in the ultrafiltration membrane is separated while adding 10 L of hydrochloric acid aqueous solution of pH 3 and 5 L of pure water, and SiO ₂ · Al in which some of the constituent components of the core particles forming the first silica coating layer are removed. A dispersion of ₂ O ₃ porous particles was prepared (step (c)). A mixture of 1500 g of the above porous particle dispersion, 500 g of pure water, 1,750 g of ethanol, and 626 g of 28% ammonia water is heated to 35 ° C., and then 104 g of ethyl silicate (SiO ₂ 28 mass%) is added, The surface of the porous particles on which the first silica coating layer was formed was coated with a hydrolyzed polycondensate of ethyl silicate to form a second silica coating layer. Next, a dispersion of silica-based fine particles (P-1) having a solid content concentration of 20% by mass in which the solvent was replaced with ethanol using an ultrafiltration membrane was prepared.

The thickness of the first silica coating layer of the hollow silica-based fine particles was 3 nm, the average particle size was 47 nm, MOx / SiO ₂ (molar ratio) was 0.0017, and the refractive index was 1.28. Here, the average particle diameter was measured by a dynamic light scattering method.

(Reflective color unevenness)
The reflected color unevenness was visually evaluated according to the following criteria.

◎: Change in color tone of reflected light is not recognized ○: Change in color tone of reflected light is recognized in a small part (less than 10% of area)
Δ: Partial change in color of reflected light is recognized (10% or more and less than 30% of area)
X: Change in color tone of reflected light was observed as a whole. The results are shown in Table 2, but it was found that the antireflection film produced using the hard coat film of the present invention showed excellent unevenness in reflected color. .

Example 3
In accordance with the following method, antireflection films 1, 14, and 19 produced using hard coat films 1, 14, and 19 and Konica Minolta Tack KC8UCR-3 (made by Konica Minolta Opto Co., Ltd.), each of which is a retardation film, each 1 A polarizing plate was produced using the sheet as a polarizing plate protective film.

(A) Production of Polarizing Film A long polyvinyl alcohol film having a thickness of 120 μm was uniaxially stretched (temperature: 110 ° C., stretch ratio: 5 times). This was immersed in an aqueous solution composed of 0.075 g of iodine, 5 g of potassium iodide, and 100 g of water for 60 seconds, and then immersed in an aqueous solution at 68 ° C. composed of 6 g of potassium iodide, 7.5 g of boric acid, and 100 g of water. . This was washed with water and dried to obtain a long polarizing film.

(B) Production of Polarizing Plate Next, according to the following Steps 1 to 5, the polarizing film and the polarizing plate protective film were bonded together to produce a polarizing plate.

  Step 1: The antireflection film and KC8UCR-3 were immersed in a 2 mol / L sodium hydroxide solution at 60 ° C. for 90 seconds, then washed with water and dried. A surface of the antireflection film provided with the antireflection layer was previously protected with a peelable protective film (PET).

  Process 2: The above-mentioned polarizing film was immersed for 1 to 2 seconds in the polyvinyl alcohol adhesive tank of 2 mass% of solid content.

  Step 3: Excess adhesive adhered to the polarizing film in Step 2 was lightly removed, and it was sandwiched between KC8UCR-3 that had been subjected to alkali treatment in Step 1 and an antireflection film, and laminated.

Process 4: It bonded together by the speed of about 2 m / min with the pressure of 20-30 N / cm < ² > with the two rotating rollers. At this time, care was taken to prevent bubbles from entering.

  Step 5: The sample prepared in Step 4 in a dryer at 80 ° C. was dried for 2 minutes to prepare a polarizing plate.

  The polarizing plate on the outermost surface of a commercially available liquid crystal display panel (NEC color liquid crystal display MultiSync LCD1525J: model name LA-1529HM) is carefully peeled off, and the polarizing plate with the polarization direction aligned is placed on the surface side with the antireflection film A liquid crystal display device was produced by pasting in this manner.

  As a result of the evaluation, the liquid crystal display device using the antireflection films 14 and 19 of the present invention was superior in visibility, color tone, and displayability as compared with the comparative example using the antireflection film 1 of the comparative example.

Example 4
Except that the hard coat layer coating composition 1 of Example 1 was changed to the following antiglare hard coat layer coating solution, the antiglare hard coat films 1 to 23 were produced, and the scratch resistance and blocking properties were improved. When evaluated, Example 1 was reproduced and had excellent scratch resistance and blocking properties. The center line average roughness Ra on the surface of the antiglare hard coat film was 120 nm. The center line average roughness Ra is a numerical value defined in JIS B 0601, and was measured using a non-contact surface fine shape measuring device WYKO NT-2000.

  Furthermore, using the antiglare hard coat films 1 to 23 in the same manner as in Examples 2 and 3, an antiglare antireflection film, a polarizing plate using the same, and a liquid crystal display device were produced. The liquid crystal display device using the antiglare hard coat film had excellent antiglare properties as well as good visibility, color tone, and display properties.

(Anti-glare hard coat layer coating solution)
Acetone 45 parts by weight Ethyl acetate 45 parts by weight PGME (propylene glycol monomethyl ether) 10 parts by weight Pentaerythritol triacrylate 30 parts by weight Pentaerythritol tetraacrylate 45 parts by weight Urethane acrylate (trade name U-4HA, manufactured by Shin-Nakamura Chemical Co., Ltd.) 25 Part by mass Fluorine-containing polymethyl methacrylate fine particles (Negami Kogyo Co., Ltd., average particle size 3.5 μm)
20 parts by mass 1-hydroxy-cyclohexyl-phenyl-ketone (Irgacure 184, manufactured by Ciba Japan) 5 parts by mass 2-methyl-1- [4- (methylthio) phenyl] -2-monoforino-1-one (Irgacure 907) 3 parts by weight BYK-331 (silicone surfactant, manufactured by Big Chemie Japan Co., Ltd.)
0.5 parts by mass

It is the schematic which showed the process of heat-processing continuously after active light irradiation which concerns on this invention. It is the schematic which heat-processes the hard coat film roll after winding which concerns on this invention in the heat processing chamber A. FIG. It is a schematic diagram of the tenter apparatus used in the examples.

Explanation of symbols

Y elongated film 1 feed roll 2 transport roller 3 extrusion coater 4 counter roll 5 drying zones 6 active ray irradiation lamp unit 6a cooling actinic ray lamps 6b air-cooling Air vents 6c N ₂ for supplying the chamber 7 heating zones 8 take-up chamber 9 Winding roll 10 Hot air outlet 12 Movable carriage 15 Winding core A Heat treatment chamber

Claims (6)

In a method for producing a hard coat film in which a hard coat layer forming material is coated on a transparent film substrate to produce a hard coat film, the hard coat layer forming material contains at least one polyfunctional acrylate, and a coating step Comprises at least coating, drying, light irradiation, and heat treatment at 60 ° C. or higher after light irradiation,
The step of performing the heat treatment is performed after being wound into a roll after the light irradiation,
The method for producing a hard coat film, wherein the heating temperature in the heat treatment step is raised at a rate of 0.3 to 5 ° C / hour. The method for producing a hard coat film according to claim 1, wherein the heat treatment step is a heat treatment at 80 ° C. or higher. The method for producing a hard coat film according to claim 2, wherein the heat treatment step is a heat treatment at 120 ° C. or higher. The method for producing a hard coat film according to any one of claims 1 to 3, wherein the heating temperature in the heat treatment step is lowered at 0.3 to 5 ° C / hour. The said transparent film base material is a cellulose-ester film, The manufacturing method of the hard coat film of any one of Claims 1-4 characterized by the above-mentioned. 6. The method for producing a hard coat film according to claim 5 , wherein the cellulose ester film is produced by a melt casting film forming method.

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