JP2009186773A - Antireflection film, polarizing plate using the same, and display - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an antireflection film having high physical strength (crack preventing properties), reducing the occurrence of foreign matter failure and application irregularity in a large area antireflection film, remarkably increasing anti-staining of the large area antireflection film and improving the productivity of the large area antireflection film in the antireflection film used for the surface of an image display, such as, liquid crystal display (LCD), and to provide a polarizing plate that uses the film and a display. <P>SOLUTION: The antireflection film having composition of a transparent film base material-a high refractive index layer-a low refractive index layer regulates that Martens hardness (HMs) of the surface of the high-refractive index layer, when pressing the surface of the high-refractive index layer with a micro hardness tester has 250-350 N/mm<SP>2</SP>, or designates that the Martens hardness (HMs) of the surface of the low refractive index layer, when pressing the surface of the low refractive index layer with the micro hardness tester, has 250-350 N/mm<SP>2</SP>. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an antireflection film, a polarizing plate using the same, and a display device.

  The development of the display field in recent years is remarkable, and it has been used in every scene, indoors and outdoors. It is not just for displaying still images / moving images, but, as represented by touch panels, there are many opportunities for users to directly touch the display part of the display. The demand for strength to the environment is also increasing.

  In general, an antireflection film is used in an image display device such as a cathode ray tube display device (CRT), a plasma display (PDP), an electroluminescence display (ELD), or a liquid crystal display device (LCD). In order to prevent the reflection of an image, it has a function of reducing the reflectance by optical interference of the multilayer thin film, and is disposed on the outermost surface of the display.

In general, the antireflection is performed by forming a low refractive index layer having a lower refractive index than the lower layer directly on the transparent film substrate or via another layer. Further, when the surface of the optical article is damaged, the visibility of the display panel is deteriorated, so that hard performance is imparted to the antireflection film. Furthermore, since the optical article made of plastic is insulative, it is charged with static electricity or the like, and anti-static performance is imparted to prevent the visibility of the display panel from being deteriorated due to dust adhering to the surface. It is demanded.
JP 2002-267804 A In JP-A-2006-35624, Patent Document 1 and Patent Document 2 disclose, as a method for imparting these hard performance and antistatic performance, a hard coat layer is formed on a transparent film substrate, and a metal oxide is formed thereon. A method for producing an antireflection film is described in which an antistatic layer containing bismuth is formed, and a low refractive index layer having a lower refractive index than that of the lower layer is further formed thereon.

  One of keywords in the display field in recent years is an increase in screen size. There is a need for a technique that can stably produce large-screen displays of 40 inches or more in large quantities.

  Large-screen displays require a large-area optical film, and in order to produce large-screen displays stably and in large quantities, it is essential to reduce foreign matter failure and uneven coating in large-area antireflection films. It becomes.

  However, the method for producing an antireflection film described in Patent Documents 1 and 2 has a problem that foreign matter failure and coating unevenness in the large-area antireflection film cannot be reduced.

  The object of the present invention is to solve the above-mentioned problems of the prior art, have high physical strength, and enable foreign matter failure and coating unevenness in the large area antireflection film to be reduced. An object of the present invention is to provide an antireflection film, a polarizing plate using the same, and a display device that can greatly increase the productivity and can improve the productivity of a large-area antireflection film.

  As a result of intensive studies in view of the above points, the present inventor, as a result of an antireflection film having a transparent film substrate-high refractive index layer-low refractive index layer structure, on the surface of the high refractive index layer, a microhardness meter. By defining the Martens hardness of the surface of the high refractive index layer when a predetermined thickness is pressed in, the range where the film density of the high refractive index layer is low and the film strength is weak can be removed. The trouble of laminating the low refractive index layer on the surface can be avoided and the range of the weakness (flexibility degradation) of the film surface of the high refractive index layer can be removed. It has been found that troubles when laminating a low refractive index layer can be avoided.

  In addition, the present inventors similarly, when the antireflection film having the configuration of transparent film substrate-high refractive index layer-low refractive index layer is pressed into the surface of the low refractive index layer to a predetermined thickness with a microhardness meter By defining the Martens hardness on the surface of the low refractive index layer, it is possible to remove the range where the film density of the low refractive index layer is low and the film strength is weak, and the antifouling property is deteriorated on the surface of the low refractive index layer. In addition to preventing the occurrence of cracks during the production of antireflection films, it is possible to eliminate the range of fragility (flexibility deterioration) of the film surface of the low refractive index layer. And consequently, the antifouling property of the large-area antireflection film can be greatly increased, and the productivity of the large-area antireflection film can be improved, and the present invention has been completed. so That.

In order to achieve the above object, the invention of claim 1 includes a high refractive index layer having a refractive index higher than that of the transparent film substrate and a low refractive index lower than that of the transparent film substrate on the transparent film substrate. An antireflection film having a refractive index layer, and the Martens hardness (HMs) of the surface of the high refractive index layer when the surface of the high refractive index layer is pressed with a microhardness meter is 250 N / mm ² or more, 350 N / mm It is characterized by having ² or less.

  Here, the Martens hardness (HMs) on the surface of the high refractive index layer is a microhardness meter using a Vickers indenter and a triangular pyramid indenter having an angle between ridges of 115 degrees. In the load test force-indentation depth curve when the indenter is pushed down to approximately 1/10 of the thickness of the refractive index layer, the maximum load test force (Fmax) obtained from the load test force-indentation depth curve ) Is a value defined by the following equation from the slope (m) in which the indentation depth from the 50% value to the 90% value is proportional to the square root of the load test force.

1HMs = 1 / (26.43m ² )
The invention according to claim 2 is an antireflection film comprising a high refractive index layer having a refractive index higher than that of the transparent film substrate and a low refractive index layer having a refractive index lower than that of the transparent film substrate on the transparent film substrate. And the Martens hardness (HMs) of the surface of the low refractive index layer when the surface of the low refractive index layer is pressed with a microhardness meter has a value of 250 N / mm ² or more and 350 N / mm ² or less. It is a feature.

  Here, the Martens hardness (HMs) on the surface of the low refractive index layer is a microhardness meter using a Vickers indenter and a triangular pyramid indenter with an angle between ridges of 115 degrees. In the load test force-indentation depth curve when the indenter is pushed down to approximately 1/10 of the thickness of the refractive index layer, the maximum load test force (Fmax) obtained from the load test force-indentation depth curve ) Is a value defined by the following equation from the slope (m) in which the indentation depth from the 50% value to the 90% value is proportional to the square root of the load test force.

1HMs = 1 / (26.43m ² )
The invention of the polarizing plate according to claim 3 is characterized in that the antireflection film according to claim 1 or 2 is bonded to at least one of the two surfaces of the polarizer.

  The invention of a display device according to claim 4 is characterized in that the antireflection film according to claim 1 or 2 is used.

  The invention of a display device according to a fifth aspect is characterized in that the polarizing plate according to the third aspect is used.

The invention of claim 1 is an antireflection film having a structure of transparent film substrate-high refractive index layer-low refractive index layer, and the surface of the high refractive index layer when the surface of the high refractive index layer is pressed with a microhardness meter. The Martens hardness (HMs) is 250 N / mm ² or more and 350 N / mm ² or less. According to the invention of claim 1, the Martens hardness of the surface of the high refractive index layer of the antireflection film is specified. The effect of having high physical strength, enabling foreign matter failure and coating unevenness to be reduced, greatly increasing the antifouling property of the antireflection film, and improving the film productivity. Play.

Similarly, the invention of claim 2 is an antireflection film having a configuration of a transparent film substrate-a high refractive index layer-a low refractive index layer, and the low refractive index when the surface of the low refractive index layer is pressed with a microhardness meter. The layer surface has a Martens hardness (HMs) of 250 N / mm ² or more and 350 N / mm ² or less. According to the invention of claim 2, the Martens hardness of the low refractive index layer surface of the antireflection film is increased. By defining it, it has high physical strength, can reduce foreign matter failure and coating unevenness, can greatly increase the antifouling property of the antireflection film, and improve the productivity of the film There is an effect that can be done.

  The invention of a polarizing plate according to claim 3 is obtained by bonding the antireflection film having high physical strength and antifouling property according to claim 1 or 2 to at least one of both surfaces of the polarizer. Therefore, according to the invention of the polarizing plate of claim 3, when this is used for a display device, the antifouling durability of the surface of the display device is excellent and the visibility is excellent.

  The invention of the display device according to claim 4 uses the antireflection film having high physical strength and antifouling property according to claim 1 or 2, and according to the invention of the display device according to claim 4, the surface of the display device The antifouling durability is excellent, and there is an effect that the visibility is excellent.

  The invention of the display device of claim 5 uses the polarizing plate of claim 3, and according to the display device of claim 5, the antifouling durability of the display device surface is excellent and the visibility is excellent. There is an effect that.

  Next, embodiments of the present invention will be described, but the present invention is not limited thereto.

One antireflection film according to the present invention has a high refractive index layer having a refractive index higher than that of the transparent film substrate and a low refractive index layer having a refractive index lower than that of the transparent film substrate on the transparent film substrate. An antireflection film having a Martens hardness (HMs) of 250 N / mm ² or more and 350 N / mm ² or less when the surface of the high refractive index layer is pressed with a microhardness meter. is there.

  Here, the definition of the Martens hardness (HMs) on the surface of the high refractive index layer is as described above.

  The Martens hardness (HMs) of the surface of the high refractive index layer when the surface of the high refractive index layer is pressed with a micro hardness meter is the approximate thickness of the high refractive index layer. It means the Martens hardness (HMs) when pushed in by a thickness of 1/10.

  In general, the high refractive index layer of the antireflection film has a Martens hardness (HMs) value that varies depending on the composition of the high refractive index layer-forming resin composition that forms the layer. The prevention film is defined by the Martens hardness of the surface of the high refractive index layer when such a surface of the high refractive index layer is pressed by a microhardness meter to a predetermined thickness.

Here, if the Martens hardness (HMs) of the surface of the high refractive index layer when the surface of the high refractive index layer of the antireflection film is pressed with a microhardness meter is less than 250 N / mm ² , the film of the high refractive index layer When the low refractive index layer is laminated on the high refractive index layer because the density is low and the film strength is weak, components such as a solvent contained in the low refractive index layer penetrate into the high refractive index layer portion, resulting in high refraction. Since the rate layer swells and a product different from the intended design is produced, it is not preferable.

Further, when the Martens hardness (HMs) of the surface of the high refractive index layer when the surface of the high refractive index layer is pushed with a microhardness meter exceeds 350 N / mm ² , the film surface of the high refractive index layer is overcured. As a result, the brittleness (flexibility deterioration) is increased, and for example, cracks are generated during production in a roll-to-roll, and when a low refractive index layer is laminated, a film is formed at the crack part. Thickness unevenness occurs, or components such as solvents contained in the low refractive index layer penetrate into the high refractive index layer part from the crack part, and the high refractive index layer swells. It is not preferable because a different one is completed.

  As described above, the larger the production area of the antireflection film, the higher the probability of occurrence of foreign matter failure and uneven coating due to cracks in the high refractive index layer. Therefore, according to the present invention, the surface of the high refractive index layer is pushed with a microhardness meter. Even when the production area is large, the yield can be reduced by keeping the Martens hardness (HMs) on the surface of the high refractive index layer within the above specified range.

Another one of the antireflection films according to the present invention comprises a high refractive index layer having a refractive index higher than that of the transparent film substrate and a low refractive index layer having a refractive index lower than that of the transparent film substrate on the transparent film substrate. The Martens hardness (HMs) of the surface of the low refractive index layer when the surface of the low refractive index layer is pressed with a microhardness meter is 250 N / mm ² or more and 350 N / mm ² or less. It is what you have.

  Here, the Martens hardness (HMs) of the surface of the low refractive index layer when the surface of the low refractive index layer is pushed with a microhardness meter is the film thickness of the low refractive index layer. It means the Martens hardness (HMs) when pushed in by about 1/10 of the thickness.

  In general, the low refractive index layer of the antireflection film has a Martens hardness (HMs) value that varies depending on the composition of the low refractive index layer-forming resin composition that forms the layer. The prevention film is defined by the Martens hardness of the surface of the low refractive index layer when such a surface of the low refractive index layer is pressed into a predetermined thickness with a microhardness meter.

  In addition, the microhardness meter which measures Martens hardness can be effectively measured with respect to the layer which has a thickness of 0.1 nm or more.

Here, if the Martens hardness (HMs) of the surface of the low refractive index layer when the surface of the low refractive index layer is pressed with a microhardness meter is less than 250 N / mm ² , the film density of the low refractive index layer is small. Since the film strength is weak, the antifouling property on the surface deteriorates, which is not preferable.

Moreover, when the Martens hardness (HMs) of the low refractive index layer surface when the low refractive index layer surface is pressed with a microhardness meter exceeds 350 N / mm ² , the film surface of the low refractive index layer is in an overcured state. This increases the brittleness (flexibility deterioration), and for example, causes cracking during production in a roll to roll, which is not preferable.

  As described above, the larger the production area of the antireflection film, the higher the probability of occurrence of foreign matter failure and uneven coating due to cracks in the low refractive index layer. Therefore, according to the present invention, the surface of the low refractive index layer is pushed in with a microhardness meter. Even when the production area is large, the yield can be reduced by keeping the Martens hardness (HMs) on the surface of the low refractive index layer within the specified range.

  Next, the high refractive index layer having a higher refractive index than the transparent film substrate used in the antireflection film of the present invention will be described.

(High refractive index layer)
The high refractive index layer as used in the field of this invention means a layer higher than the refractive index of a transparent film base material. The preferable refractive index of the high refractive index layer is preferably in the range of 1.5 to 2.2 when measured at a temperature of 23 ° C. and a wavelength of 550 nm. The means for adjusting the refractive index of the high refractive index layer is dominated by the type and addition amount of the conductive particles, and therefore the refractive index of the conductive particles described below is 1.60 to 2.60. Preferably, it is 1.65 to 2.50.

  Further, the film thickness of the high refractive index layer is preferably 5 nm to 1 μm, more preferably 10 nm to 0.3 μm, and most preferably 30 nm to 0.2 μm from the characteristics as an optical interference layer. preferable.

  Further, the high refractive index layer may contain organic or inorganic fine particles as means for adjusting the refractive index. In particular, among the inorganic fine particles, the metal oxide fine particles can be used as a means for adjusting the refractive index of the high refractive index layer, and can impart conductivity to the high refractive index layer, so that an antireflection film is produced by roll-to-roll. At this time, dust in the air and foreign matter such as a transparent film substrate piece generated slightly during conveyance of the antireflection film are not actively adsorbed, which is preferable.

  The metal oxide fine particles contained in the high refractive index layer in the present invention are among the group consisting of antimony oxide, tin oxide, zinc oxide, tin indium oxide (ITO), tin antimonate (ATO), and zinc antimonate. Particularly preferred is at least one conductive particle selected from the group consisting of:

  The metal oxide fine particles contained in the high refractive index layer in the present invention are among the group consisting of antimony oxide, tin oxide, zinc oxide, tin indium oxide (ITO), tin antimonate (ATO), and zinc antimonate. Particularly preferred is at least one conductive particle selected from the group consisting of:

  The average particle diameter of primary particles of these conductive particles is in the range of 10 nm to 200 nm, more preferably 20 to 150 nm, and particularly preferably 30 to 100 nm. The average particle diameter of the conductive particles can be measured from an electron micrograph taken with a scanning electron microscope (SEM) or the like. Further, it may be measured by a particle size distribution meter using a dynamic light scattering method or a static light scattering method. 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 conductive particles is preferably a rice grain shape, a spherical shape, a cubic shape, a spindle shape, a needle shape, or an indefinite shape.

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

  The amount of the conductive particles used is preferably 5% by mass to 85% by mass, more preferably 10% by mass to 80% by mass, and most preferably 20% by mass to 75% by mass in the high refractive index layer. When the amount used is small, a desired refractive index cannot be obtained, and when it is too large, film strength is deteriorated.

  The conductive particles are supplied to a coating liquid 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 methanol, ethanol, and isopropanol are particularly preferable.

  Moreover, electroconductive particle can be disperse | distributed in a 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.

  Furthermore, you may contain the electroconductive particle which has a core / shell structure. 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.

  The high refractive index layer may contain an actinic radiation curable resin as a binder for the conductive particles in order to improve the film formability and physical properties of the coating film.

  As such actinic radiation curable resin, a monomer or oligomer having two or more functional groups that cause a polymerization reaction directly by irradiation with ultraviolet rays or electron beams or indirectly by the action of a photopolymerization initiator may be used. it can. Examples of the functional group include a group having an unsaturated double bond such as a (meth) acryloyloxy group, an epoxy group, and a silanol group. Among these, radically polymerizable monomers and oligomers having two or more unsaturated double bonds can be preferably used. You may combine a photoinitiator as needed. As such actinic radiation curable resin, polyol acrylate, epoxy acrylate, urethane acrylate, polyester acrylate or a mixture thereof is used. For example, a polyfunctional acrylate compound etc. are mentioned, It is preferable that it is a compound chosen from the group which consists of a pentaerythritol polyfunctional acrylate, a dipentaerythritol polyfunctional acrylate, a pentaerythritol polyfunctional methacrylate, and a dipentaerythritol polyfunctional methacrylate. Here, the polyfunctional acrylate compound is a compound having two or more acryloyloxy groups and / or methacryloyloxy groups in the molecule.

  Examples of the monomer of the polyfunctional acrylate compound include ethylene glycol diacrylate, diethylene glycol diacrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, trimethylolpropane triacrylate, trimethylolethane triacrylate, and tetramethylolmethanetriacrylate. Acrylate, tetramethylolmethane tetraacrylate, pentaglycerol triacrylate, pentaerythritol diacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, glycerin triacrylate, dipentaerythritol triacrylate, dipentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, Dipen Erythritol hexaacrylate, tris (acryloyloxyethyl) isocyanurate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, 1,6-hexanediol dimethacrylate, neopentyl glycol dimethacrylate, trimethylolpropane trimethacrylate, trimethylolethane trimethacrylate, tetra Methylol methane trimethacrylate, tetramethylol methane tetramethacrylate, pentaglycerol trimethacrylate, pentaerythritol dimethacrylate, pentaerythritol trimethacrylate, pentaerythritol tetramethacrylate, glycerin trimethacrylate, dipentaerythritol trimethacrylate, dipentaerythritol te La methacrylate, dipentaerythritol penta methacrylate, dipentaerythritol hexa methacrylate preferred. 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.

  In addition to the polyfunctional acrylate compound as described above, actinic radiation curable type containing methylene oxide, ethylene oxide, propylene oxide, 1,3-dioxane, 1,4-dioxane structure in the structure of actinic radiation curable resin A resin may be used.

  Examples of such actinic ray curable resins include methoxy polyethylene glycol acrylate, methoxy polyethylene glycol methacrylate, ethoxylated phenyl acrylate, ethoxylated phenyl methacrylate, ethoxylated 2-methyl-1,3-propanediol diacrylate, and ethoxylated 2-methyl. -1,3-propanediol dimethacrylate, ethoxylated bisphenol A diacrylate, ethoxylated propoxylated bisphenol A dimethacrylate, ethoxylated trimethylolpropane triacrylate, ethoxylated trimethylolpropane trimethacrylate, ethoxylated pentaerythritol tetraacrylate, propoxylated Ditrimethylolpropane tetraacrylate, propoxylated pentaerythritol tetraacrylate And dioxane glycol diacrylate and dioxane glycol dimethacrylate are preferred, and in particular, one or two functional groups that cause a polymerization reaction directly by irradiation with ultraviolet rays or electron beams or indirectly by the action of a photopolymerization initiator. Those having one are particularly preferred.

  The addition amount of the actinic radiation 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 the curing of the actinic radiation curable resin, it contains a photopolymerization initiator and an acrylic compound having two or more polymerizable unsaturated bonds in the molecule in a mass ratio of 1: 2 to 1:10. Is preferred.

  The mixing ratio of the actinic radiation curable resin and the conductive particles contained in the high refractive index of the antireflection film according to the present invention is a solid content in a range of 1: 3 to 5: 3, and more preferably 1: 1. .5 to 1.6: 1, more preferably 1.5: 1.2 to 1.5: 1. If it is outside this range, for example, if there are too few conductive particles, adhesion will not be able to be taken, the effect will be lost, and antistatic properties will deteriorate, and if there are too many conductive particles, during production of the antireflection film The conductive particles contained excessively fall off and adhere to the surface of the film being coated, which causes an appearance failure, which is not 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. Absent.

  An organic solvent is preferably used when applying the high refractive index layer. Examples of the organic solvent include alcohols (eg, 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, thiodiglycol, etc.), polyhydric alcohol ethers ( For example, ethylene glycol monomethyl ether, ethylene glycol 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, ethylenediamine, diethylenediamine, trie Lentetramine, tetraethylenepentamine, polyethyleneimine, pentamethyldiethylenetriamine, tetramethylpropylenediamine, etc.), amides (eg, formamide, N, N-dimethylformamide, N, N-dimethylacetamide, etc.), heterocyclics (eg, 2-pyrrolidone, N-methyl-2-pyrrolidone, cyclohexyl pyrrolidone, 2-oxazolidone, 1,3-dimethyl-2-imidazolidinone, etc.), sulfoxides (eg dimethyl sulfoxide etc.), sulfones (eg sulfolane) Etc.), urea, acetonitrile, acetone and the like, and alcohols, polyhydric alcohols, and polyhydric alcohol ethers are particularly preferable.

  For the high refractive index layer, a wet film thickness of 0.1% is applied to the surface of the transparent film or hard coat layer using a gravure coater, dip coater, reverse coater, wire bar coater, die coater, spray coating, ink jet coating, or the like. It is formed by coating at ˜100 μm, followed by heating and drying after coating, and curing as necessary. The content described in the low refractive index layer described later can be used in the curing step.

  The dry film thickness is adjusted to the above film thickness by adjusting the solid content concentration of the coating composition.

(Low refractive index layer)
Next, the low refractive index layer of the antireflection film according to the present invention will be described.

  In the low refractive index layer of the antireflection film according to the present invention, a layer having a refractive index lower than that of the transparent film substrate is referred to as a low refractive index layer. A specific refractive index is preferably in the range of 1.30 to 1.45 at 23 ° C. and a wavelength of 550 nm. Further, 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 further preferably 30 nm to 0.2 μm, from the characteristics as the optical interference layer.

  It is preferable that the low refractive index layer of the antireflection film according to the present invention contains hollow particles from the characteristics as an optical interference layer such as a low refractive index.

  The hollow particles are (1) a composite particle comprising a porous particle and a coating layer provided on the surface of the porous particle, or (2) a cavity inside, and the content is a solvent, gas or porous substance It is a hollow particle filled with.

  Note that the cavity particles are particles having a cavity inside, and the cavity is surrounded by 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. The average particle size of such hollow particles is 5 to 200 nm, preferably 10 to 70 nm. The particle size of the hollow particles is preferably monodispersed with a coefficient of variation of 1 to 40%.

  The average particle diameter of the hollow silica particles used in the present invention 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.

  The average particle diameter of the hollow particles used in the present invention is appropriately selected according to the thickness of the transparent film of the low refractive index layer to be formed, and is 3/2 to 1/10, preferably 2 of the film thickness of the transparent film. / 3 to 1/10 is desirable. These hollow 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), ketone (for example, methyl ethyl ketone, methyl isobutyl ketone), ketone alcohol (for example, diacetone alcohol), propylene monomethyl ether, propylene glycol monomethyl ether acetate and the like are preferable. .

  The thickness of the coating layer of the composite particles or the thickness of the particle walls of the hollow particles is 1 to 40 nm, preferably 1 to 20 nm, more 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 the coating liquid component can easily enter the composite particles to reduce the internal porosity. However, the effect of lowering the refractive index may not be obtained sufficiently. In addition, when the thickness of the coating layer exceeds 20 nm, the coating liquid component does not enter the inside, but the porosity (pore volume) of the composite particles is lowered and the effect of lowering the refractive index cannot be sufficiently obtained. Sometimes.

  In the case of hollow particles, when the particle wall thickness is less than 1 nm, the particle shape may not be maintained, and even when the thickness exceeds 20 nm, the effect of lowering the refractive index may not be sufficiently exhibited. is there.

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, 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. Of these, porous particles made of a composite oxide of silica and an inorganic compound other than silica are particularly suitable.

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 or more types can be mentioned. In such porous particles, silica expressed as SiO _2, in terms of oxide of the inorganic compound other than silica (MO _x) with expressed molar ratio when: MOx / SiO ₂ is 0.0001 to 1.0, Preferably it is in the range of 0.001 to 0.3.

A porous particle having a molar ratio of MOx / SiO ₂ of less than 0.0001 is difficult to obtain, and even if obtained, a pore volume is small and particles having a low refractive index cannot be obtained. Further, when the molar ratio of the porous particles: MOx / SiO ₂ exceeds 1.0, the silica ratio decreases, so that the pore volume increases and it may be difficult to obtain a low refractive index.

  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. When the pore volume is less than 0.1 ml / g, particles having a sufficiently reduced refractive index cannot be obtained, and when the pore volume exceeds 1.5 ml / g, the strength of the 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 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 particles, for example, the method for preparing composite oxide colloidal particles disclosed in paragraphs [0010] to [0033] of JP-A-7-133105 is preferably employed. Specifically, when the composite particles are composed of silica and an inorganic compound other than silica, hollow particles can be produced by carrying out 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 mixed aqueous solution of a silica raw material and an inorganic compound raw material other than silica is prepared in advance. According to the composite ratio of the target composite oxide, a porous particle precursor is prepared by gradually adding it to an alkaline aqueous solution having a pH of 10 or more while stirring.

  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, and inorganic oxide particles such as SiO ₂ , Al ₂ O ₃ , TiO ₂ , or ZrO ₂ , or composite oxide particles thereof are used. Usually, these sols are used. be able to. Furthermore, the porous particle precursor dispersion obtained by the above production method may be used as a seed particle dispersion.

  When the seed particle dispersion is used, the pH of the seed particle dispersion is adjusted to 10 or more, and then an aqueous solution of the above compound is added to the 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 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 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 oxide (MOx), and the molar ratio of MOx / SiO ₂ is 0.05 to 2.0, preferably It is desirable to be within the range of 0.2 to 2.0. Within this range, the pore volume of the porous particles increases as the silica proportion 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 hollow particles, the molar ratio of MOx / SiO ₂ is preferably in the range of 0.25 to 2.0.

(Second step: removal of inorganic compounds other than silica from porous particles)
In the second step, at least a part of inorganic compounds other than silica (elements other than silicon and oxygen) is selectively removed from the porous particle precursor obtained in the first step. 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 form a silica protective film by adding a silicic acid solution containing an alkyl group-containing silane compound, an organic silicon compound, a hydrolyzate thereof, or a polycondensate thereof. The thickness of the silica protective film may be 0.5 to 40 nm, preferably 0.5 to 15 nm. Even if a 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 from the porous particle precursor. is there.

  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. be able to. 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.

  Further, 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 body, 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 organosilicon compound used for forming the silica protective film, its hydrolyzate or its polycondensate is represented by the following general formula (1).
R _n Si (OR ′) _4-n (1)
In the formula, R and R ′ represent a hydrocarbon group such as an alkyl group, an aryl group, a vinyl group, and an acrylic group, and n represents 0, 1, 2, or 3.

The alkoxysilane represented by these can be used. In particular, tetraalkoxysilanes such as fluorine-substituted tetramethoxysilane, tetraethoxysilane, and tetraisopropoxysilane are preferably used.

  As a method of addition, 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 porous particles, and then alkoxysilane, pure water, and alcohol are added. A solution obtained by adding a small amount of alkali or acid as a catalyst to a mixed solution of the above is added to a dispersion of porous particles, and a silicic acid polymer produced by hydrolyzing alkoxysilane is deposited on the surface of 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.

(3rd process: Formation of a silica coating layer)
In the third step, a hydrolyzable organosilicon compound or silica containing a fluorine-substituted alkyl group-containing silane compound is added to the porous particle dispersion (in the case of hollow particles, a hollow particle precursor dispersion) prepared in the second step. By adding an acid solution or the like, the surface of the particles is coated with a hydrolyzable organosilicon compound or a polymer such as a silicic acid solution to form a silica coating layer.

  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 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 40 nm, Preferably, it is added in an amount of 1 to 20 nm in a dispersion of porous particles (in the case of hollow particles, 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 40 nm, preferably 1 to 20 nm. The

  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 lowering the refractive index may not be obtained.

  The refractive index of the hollow silica particles thus obtained is as low as less than 1.42. Such hollow silica particles are presumed to have a low refractive index because the porosity inside the porous particles is maintained or the inside is hollow.

  From the viewpoint of stability when added to the coating composition, the hollow particles are preferably hollow particles in which a polymer having a hydrocarbon main chain is covalently bonded to the surface.

  Next, hollow particles in which a polymer having a hydrocarbon main chain is covalently bonded will be described. The polymer having a hydrocarbon main chain is a direct covalent bond, or a binder is interposed between the silica on the surface of the hollow silica particles and the polymer having the hydrocarbon main chain, and the silica and the binder are covalently bonded. It also refers to a covalent bond between a binder and a polymer. As the binder, a coupling agent is preferably used.

  Hollow particles in which a polymer having a hydrocarbon main chain is covalently bonded can be (1) capable of forming a covalent bond with the hollow silica particle surface in a state where the hollow silica particle surface is untreated or treated with a coupling agent or the like. A method in which a polymer having a functional group is reacted and the polymer is grafted on the surface of the hollow silica particles, or (2) a single amount from the surface of the hollow silica particles in a state where the surface of the hollow silica particles is untreated or treated with a coupling agent or the like. The polymer can be produced by polymerizing the body to grow a polymer chain and surface grafting. As a specific manufacturing method, the method described in JP-A-2006-257308 can be used.

  In the above production method, from the viewpoint of improving the surface modification rate, a method in which a monomer is polymerized from the surface of the hollow silica particles to grow a polymer chain and surface grafting is preferable. More preferred is a method in which hollow silica particles are surface-treated with a coupling agent containing a functional group having a polymerization initiating ability or a chain transfer ability, monomers are polymerized therefrom, polymer chains are grown, and surface grafting is performed. As a surface treatment agent (coupling agent) for introducing a functional group having polymerization initiating ability or chain transfer ability into hollow silica particles, an alkoxy metal compound (for example, titanium coupling agent, alkoxysilane compound (silane coupling agent) )) Is preferably used.

  The hollow silica particles may contain two or more kinds of hollow silica particles having different average particle diameters.

  Next, a coating composition for forming a low refractive index layer other than at least hollow silica particles having a porous or hollow interior will be described.

  By controlling the surface (film surface) pH of the low refractive index layer to 2 to 7, reaction in the low refractive index layer is suppressed, which is preferable in terms of improving the durability of the antireflection film at high humidity. More preferably, the surface (film surface) pH of the low refractive index layer is 2-4. In order to control the surface (film surface) pH of the low refractive index layer, it is preferable to add a compound having at least one pKa value in the range of pKa2 to 7 to the composition forming the low refractive index layer.

  PKa is an acid dissociation constant in the following acid dissociation reaction, which is a logarithmic value of Ka, and is a numerical value represented by pKa = −log10Ka.

HA ← → [H ⁺ ] [A ⁻ ]
Ka = [H ⁺ ] [A ⁻ ] / [HA]
As used herein, H ⁺ represents an acidic species, and A ⁻ represents a conjugate base.

  Specific compounds having at least one pKa value in the range of pKa2 to 7 include aliphatic dibasic acids, imidazoles represented by the following general formula (2), or derivatives thereof. In particular, it is preferable to contain imidazole represented by the following general formula (2) or a derivative thereof in the low refractive index layer forming composition from the standpoint of further exerting the effect even after a more severe durability test.

(R ¹ ) nA (2)
R ¹ represents a hydrogen atom, an amino group or an alkyl group having 1 to 3 carbon atoms, an alkenyl group and a halogen atom which may be substituted by a hydroxyl group, and when there are a plurality of R ^{1 s} , they may be the same or different. The amino group represented by R ¹ may be substituted with 1 or 2 methyl groups or ethyl groups. The alkyl group and alkenyl group may be substituted with an alkyl group having 1 to 3 carbon atoms. n is an integer of 1 to 3. A represents an imidazolyl group.

  Next, specific examples of imidazole represented by the above general formula (2) or derivatives thereof will be shown, but the present invention is not limited thereto. In addition, imidazole or its derivatives can be purchased and used.

1-methylimidazole 2-methylimidazole 4-methylimidazole 4- (2-hydroxyethyl) imidazole 4- (2-aminoethyl) imidazole 2- (2-hydroxyethyl) imidazole 2-ethylimidazole 2-vinylimidazole 4-propyl Imidazole 2,4-Dimethylimidazole 2-Chloroimidazole 4,5-Di (2-hydroxyethyl) imidazole As the aliphatic dibasic acid, formic acid, propionic acid, malonic acid, succinic acid, tartaric acid, malic acid, maleic acid, Examples include fumaric acid, glutaric acid, adipic acid, acetic acid, and the like. Among these, acetic acid is preferable.

  The stability of the coating composition is that the aliphatic dibasic acid or the imidazole represented by the general formula (2) or a derivative thereof is 0.05 to 10.0% by mass in the low refractive index layer coating composition. From the point of view, it is preferable.

  The coating composition for forming 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), 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 solid content concentration in the coating composition for forming the low refractive index layer is preferably 1 to 4% by mass. By setting the solid content concentration to 4% by mass or less, coating unevenness is less likely to occur, and 1% by mass. By setting it as% or more, the drying load is reduced.

  The coating composition for forming the low refractive index layer preferably contains a fluorine-based or silicone-based surfactant. Inclusion of the surfactant is effective for reducing coating unevenness and improving the antifouling property of the film surface.

  Fluorosurfactants include perfluoroalkyl group-containing monomers, oligomers, and polymers as the core, and include derivatives such as polyoxyethylene alkyl ether, polyoxyethylene alkyl allyl ether, and polyoxyethylene. It is done.

  Commercially available fluorine-based surfactants can also be used, for example, Surflon S-381, S-382, SC-101, SC-102, SC-103, SC-104 (Asahi Glass Co., Ltd.) , FLORARD FC-430, FC-431, FC-173 (Fluorochemicals-manufactured by Sumitomo 3M), F-top EF352, EF301, EF303 (made by Shin-Akita Kasei Co., Ltd.), Schwegau Fluer 8035, 8036 (Manufactured by Schwegman), BM1000, BM1100 (manufactured by BM Himmy), Megafac F-171, F-470 (manufactured by Dainippon Ink & Chemicals, Inc.), and the like.

  The fluorine content of the fluorosurfactant is 0.05 to 2% by mass, preferably 0.1 to 1% by mass. One or two or more of the above fluorosurfactants can be used in combination.

  Next, the silicone surfactant will be described.

  Silicone surfactants can be broadly classified into straight silicone oils and modified silicone oils depending on the type of organic group bonded to the silicon atom.

  Here, the straight silicone oil refers to one in which a methyl group, a phenyl group, or a hydrogen atom is bonded as a substituent. A modified silicone oil is one having a component that is secondarily derived from a straight silicone oil. On the other hand, it can be classified from the reactivity of silicone oil. These are summarized as follows.

(Silicone oil)
1. Straight silicone oil 1-1. Non-reactive silicone oil: dimethyl, methylphenyl substitution, etc. 1-2. Reactive silicone oil: methyl hydrogen substitution and the like.

2. Modified silicone oil Modified silicone oil is born by introducing various organic groups into dimethyl silicone oil.

  2-1. Non-reactive modified silicone oil: alkyl, alkyl / aralkyl, alkyl / polyether, polyether, higher fatty acid ester substitution, etc.

  The alkyl / aralkyl-modified silicone oil is a silicone oil in which a part of the methyl group of dimethyl silicone oil is substituted with a long-chain alkyl group or a phenylalkyl group.

  The polyether-modified silicone oil is a surfactant in which hydrophobic dimethyl silicone is introduced into hydrophilic polyoxyalkylene.

  The higher fatty acid-modified silicone oil is a silicone oil in which a part of the methyl group of dimethyl silicone oil is replaced with a higher fatty acid ester.

  The amino-modified silicone oil is a silicone oil having a structure in which a part of the methyl group of the silicone oil is substituted with an aminoalkyl group.

  The epoxy-modified silicone oil is a silicone oil having a structure in which a part of the methyl group of the silicone oil is substituted with an epoxy group-containing alkyl group.

  The carboxyl-modified or alcohol-modified silicone oil is a silicone oil having a structure in which a part of the methyl group of the silicone oil is substituted with a carboxyl group or a hydroxyl group-containing alkyl group.

  Of these, polyether-modified silicone oil is preferably added. The number average molecular weight of the polyether-modified silicone oil is, for example, 1,000 to 100,000, preferably 2,000 to 50,000. When the number average molecular weight is less than 1,000, the drying property of the coating film is low. Conversely, if the number average molecular weight exceeds 100,000, bleeding out to the coating surface becomes difficult.

  Specific products include L-45, L-9300, FZ-3704, FZ-3703, FZ-3720, FZ-3786, FZ-3501, FZ-3504, FZ-3508, FZ-3705, FZ-3707. , FZ-3710, FZ-3750, FZ-3760, FZ-3785, FZ-3785, Y-7499 (manufactured by Nippon Unicar Co., Ltd.), KF96L, KF96, KF96H, KF99, KF54, KF965, KF968, KF56, KF995, KF351, KF351A, KF352, KF353, KF354, KF355, KF615, KF618, KF945, KF6004, FL100 (manufactured by Shin-Etsu Chemical Co., Ltd.), surfactant BYK series, BYK-300 / 302, BYK-306, BYK-307, BYK-31 BYK-315, BYK-320, BYK-322, BYK-323, BYK-325, BYK-330, BYK-331, BYK-333, BYK-337, BYK-340, BYK-344, BYK-370, BYK -375, BYK-377, BYK-352, BYK-354, BYK-355 / 356, BYK-358N / 361N, BYK-357, BYK-390, BYK-392, BYK-UV3500, BYK-UV3510, BYK-UV3570 BYK-Silclean 3700 (manufactured by Big Chemie Japan), XC96-723, YF3800, XF3905, YF3057, YF3807, YF3802, YF3897 (manufactured by GE Toshiba Silicone), and the like.

  The silicone surfactant is a surfactant obtained by substituting a part of the methyl group of the silicone oil with a hydrophilic group. The position of substitution includes a side chain of silicone oil, both ends, one end, both end side chains, and the like. Examples of the hydrophilic group include polyether, polyglycerin, pyrrolidone, betaine, sulfate, phosphate, and quaternary salt.

  As the silicone surfactant, a nonionic surfactant having a hydrophobic group composed of dimethylpolysiloxane and a hydrophilic group composed of polyoxyalkylene is preferable.

  A nonionic surfactant is a generic term for surfactants that do not have a group capable of dissociating into ions in an aqueous solution. Oxyethylene) or the like as a hydrophilic group. Hydrophilicity increases as the number of alcoholic hydroxyl groups increases and as the polyoxyalkylene chain (polyoxyethylene chain) becomes longer. When a nonionic surfactant composed of dimethylpolysiloxane as a hydrophobic group and polyoxyalkylene as a hydrophilic group is used, unevenness of the low refractive index layer and antifouling property of the film surface are improved. It is thought that the hydrophobic group made of polymethylsiloxane is oriented on the surface and forms a film surface that is not easily soiled.

  Specific examples of the nonionic surfactant include, for example, silicone surfactants SILWET L-77, L-720, L-7001, L-7002, L-7604, Y-7006, FZ-2101, FZ-2104, FZ. -2105, FZ-2110, FZ-2118, FZ-2120, FZ-2122, FZ-2123, FZ-2130, FZ-2154, FZ-2161, FZ-2162, FZ-2163, FZ-2164, FZ-2166 FZ-2191, SUPERSILWET SS-2801, SS-2802, SS-2803, SS-2804, SS-2805 (manufactured by Nihon Unicar Co., Ltd.) and the like.

  Preferred structures of these nonionic surfactants comprising a hydrophobic group of dimethylpolysiloxane and a hydrophilic group of polyoxyalkylene include linear structures in which dimethylpolysiloxane structural portions and polyoxyalkylene chains are alternately and repeatedly bonded. A block copolymer is preferred. It is preferable from unevenness suppression and leveling properties when a coating composition for forming a low refractive index layer is applied. Specific examples of these include silicone surfactants ABN SILWET FZ-2203, FZ-2207, FZ-2208, and FZ-2222 (manufactured by Nihon Unicar Co., Ltd.).

  The coating composition for forming the low refractive index layer has a reactive modified silicone resin (also referred to as a reactive modified silicone oil) described below from the viewpoint that it is easy to exert an effect even after a durability test under more severe conditions. It is preferable to contain.

  2-2. Reactive modified silicone oil: amino, epoxy, carboxyl, alcohol substitution, etc.

  The reactive modified silicone resin is a reactive type modified silicone resin in which the side chain, one end or both ends of polysiloxane is substituted with amino, epoxy, carboxyl, hydroxyl group, methacryl, mercapto, phenol or the like. As amino-modified silicone resins, specifically, KF-860, KF-861, X-22-161A, X-22-161B (above, manufactured by Shin-Etsu Chemical Co., Ltd.), FM-3311, FM-3325 (above, Chisso Co., Ltd.), epoxy-modified silicone resins such as KF-105, X-22-163A, X-22-163B, KF-101, KF-1001 (above, Shin-Etsu Chemical Co., Ltd.), polyether-modified X-22-4272, X-22-4952 as silicone resins, X-22-3701E, X-22-3710 (above, manufactured by Shin-Etsu Chemical Co., Ltd.) as carboxyl-modified silicone resins, and carbinol-modified silicone resins KF-6001, KF-6003 (Shin-Etsu Chemical Co., Ltd.), methacryl-modified silicone X-22-164C (made by Shin-Etsu Chemical Co., Ltd.) as the resin, KF-2001 (made by Shin-Etsu Chemical Co., Ltd.) as the mercapto-modified silicone resin, and X-22-1821 as the phenol-modified silicone resin (The above is manufactured by Shin-Etsu Chemical Co., Ltd.). Examples of the hydroxyl group-modified silicone resin include FM-4411, FM-4421, FM-DA21, FM-DA26 (manufactured by Chisso Corporation). In addition, X-22-170DX, X-22-2426, X-22-176F (manufactured by Shin-Etsu Chemical Co., Ltd.) and the like are also included.

  The above-described surfactants may be used in combination with other surfactants. Also, for example, anionic surfactants such as sulfonate, sulfate, phosphate, etc. You may use together with nonionic surfactants, such as an ether type | mold and ether ester type | mold etc. which have oxyethylene chain hydrophilic group. The addition amount of the surfactant described above is 0.05 to 3.0% by mass in the low refractive index layer coating composition, not only to improve the water repellency, oil repellency and antifouling property of the coating film. From the standpoint of exerting an effect on the scratch resistance of the surface.

  The coating composition for forming the low refractive index layer can contain other silica particles. Here, the other silica particles are not particularly limited, and examples thereof include colloidal silica. Specific examples of colloidal silica are those in which silicon dioxide is dispersed in water or an organic solvent in a colloidal form, and are not particularly limited, but are spherical, acicular or beaded.

  The average particle size of the colloidal silica is preferably in the range of 50 to 300 nm, and is preferably monodispersed with a coefficient of variation of 1 to 40%. The average particle diameter 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.

  Colloidal silica is commercially available, and examples thereof include the Snowtex series of Nissan Chemical Industries, the Cataloid-S series of Catalytic Chemical Industry, and the Lebasil series of Bayer. Further, bead-like colloidal silica in which primary particles of colloidal silica or silica cation-modified with alumina sol or aluminum hydroxide are bonded to each other with metal ions having a valence of 2 or more and connected in a bead shape is also preferably used. There are beaded colloidal silicas such as SNOWTEX-AK series, SNOWTEX-PS series, SNOWTEX-UP series of NISSAN CHEMICAL INDUSTRIES, and specifically IPS-ST-L (isopropanol dispersion, particle size 40-50 nm, Solid content 30%), MEK-ST-MS (methyl ethyl ketone dispersion, particle diameter 17-23 nm, solid content 35) and the like.

  When colloidal silica is contained in the low refractive index layer-forming coating composition, it is preferably 10 to 60% by mass, more preferably 30 to 60% by mass, based on the solid content in the low refractive index layer, from the viewpoint of film strength. .

  Moreover, it is preferable that 5-80 mass% binder is included in the coating composition for low refractive index layer formation with respect to solid content in a low refractive index layer. The binder has a function of adhering particles such as hollow silica particles and maintaining the structure of the low refractive index layer including voids. The usage-amount of a binder is adjusted so that the intensity | strength of a low-refractive-index layer can be maintained, without filling a space | gap.

  Examples of binders include alkoxy metal compounds and hydrolysates or polycondensates thereof, and also polyvinyl alcohol, polyoxyethylene, polymethyl methacrylate, polymethyl acrylate, diacetyl cellulose, triacetyl cellulose, nitrocellulose, polyester, and alkyd resins. , Fluoroacrylate, fluorine-containing polymer and the like. Examples of the fluoropolymer include fluoroolefins (for example, fluoroethylene, vinylidene fluoride, tetrafluoroethylene, perfluorooctylethylene, hexafluoropropylene, perfluoro-2,2-dimethyl-1,3-dioxole, etc.) Examples thereof include partial acrylic acid or fully fluorinated alkyl ester derivatives (for example, Biscoat 6FM (manufactured by Osaka Organic Chemical Co., Ltd.) and M-2020 (manufactured by Daikin)), and fully or partially fluorinated vinyl ethers. Are perfluoroolefins, and hexafluoropropylene is particularly preferable from the viewpoint of refractive index, solubility, transparency, availability, and the like.

  As the alkoxy metal compound, the organosilicon compound described in the above-mentioned section of the high refractive index layer, its hydrolyzate or its polycondensate is particularly preferable because of its excellent properties as a binder for the hollow silica particles.

  The low refractive index layer can contain a compound represented by the following general formula (3) or a chelate compound thereof, and can improve physical properties such as hardness.

AnMBx-n (3)
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 (3) 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, aluminum alkoxide or chelate compounds thereof.

  Preferred chelating agents for coordination with free metal compounds to form chelate compounds include alkanolamines such as diethanolamine and triethanolamine, glycols such as ethylene glycol, diethylene glycol and propylene glycol, acetylacetone and acetoacetate 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 amount of the chelate compound added is preferably adjusted to be 0.3 to 5% by mass in the low refractive index layer. 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 low refractive index layer is a gravure coater, a dip coater, a reverse coater, a wire bar coater, a die coater, a known method such as an inkjet method, and the above coating composition for forming the low refractive index layer is applied, and after coating, It is formed by heat drying and curing treatment as necessary.

  The coating amount is suitably 0.05 to 100 μm, preferably 0.1 to 50 μm, as the wet film thickness. Further, the solid content concentration of the coating composition is adjusted so that the dry film thickness becomes the film pressure.

Moreover, after forming a low refractive index layer, you may include the process of heat-processing at the temperature of 50-160 degreeC. The period of the heat treatment may be appropriately determined depending on the set temperature. For example, if it is 50 ° C., it is preferably a period of 3 days or more and less than 30 days, and if it is 160 ° C., a range of 10 minutes or more and 1 day or less is preferable. . Examples of the curing method include a method of thermosetting by heating, a method of curing by irradiation with light such as ultraviolet rays, and the like. In the case of thermosetting, the heating temperature is preferably 50 to 300 ° C, preferably 60 to 250 ° C, more preferably 80 to 150 ° C. When curing by light irradiation, exposure of the irradiation light is ^{preferably, 100mJ / cm 2 ~500mJ / cm} 2 and more preferably ^{10mJ / cm 2 ~10J / cm 2} .

Here, the wavelength range of the irradiated light is not particularly limited, but light having a wavelength in the ultraviolet region is preferably used. Specifically, 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. Irradiation conditions vary depending on each lamp, but the irradiation amount of active rays is usually 5 to 500 mJ / cm ² , preferably 5 to 150 mJ / cm ² , and particularly preferably 20 to 100 mJ / cm ² .

(Hard coat layer: actinic radiation curable resin layer)
The antireflection film of the present invention is provided with a layer containing an actinic radiation curable resin as a hard coat layer between the transparent film substrate and the antireflection layer. It is preferable because it is difficult to be damaged in the process of making the polarizing plate.

  The actinic radiation curable resin layer refers to a layer mainly composed of a resin that is cured through a crosslinking reaction or the like by irradiation with actinic rays such as ultraviolet rays or electron beams. As the actinic radiation curable resin, a component containing a monomer having an ethylenically unsaturated double bond is preferably used, and an actinic radiation curable resin layer is formed by curing by irradiation with actinic radiation such as ultraviolet rays or electron beams. The Typical examples of the actinic radiation curable resin include an ultraviolet curable resin and an electron beam curable resin, and a resin curable by ultraviolet irradiation is preferable.

  As the ultraviolet curable resin, for example, an ultraviolet curable urethane acrylate resin, an ultraviolet curable polyester acrylate resin, an ultraviolet curable epoxy acrylate resin, an ultraviolet curable polyol acrylate resin, or an ultraviolet curable epoxy resin is preferable. Used. Of these, ultraviolet curable acrylate resins are preferred.

  The UV curable acrylic urethane resin generally includes 2-hydroxyethyl acrylate and 2-hydroxyethyl methacrylate (hereinafter referred to as acrylate) in addition to a product obtained by reacting a polyester polyol with an isocyanate monomer or a prepolymer. It can be easily obtained by reacting an acrylate monomer having a hydroxyl group such as 2-hydroxypropyl acrylate. For example, those described in JP 59-151110 A can be used.

  For example, a mixture of 100 parts Unidic 17-806 (Dainippon Ink Co., Ltd.) and 1 part Coronate L (Nihon Polyurethane Co., Ltd.) is preferably used.

  Examples of UV curable polyester acrylate resins include those which are easily formed when 2-hydroxyethyl acrylate and 2-hydroxy acrylate monomers are generally reacted with polyester polyols. JP-A-59-151112 Those described in the publication can be used.

  Specific examples of the ultraviolet curable epoxy acrylate resin include an epoxy acrylate as an oligomer, a reactive diluent and a photopolymerization initiator added thereto, and reacted to form an oligomer. Those described in Japanese Patent No. 105738 can be used.

  Specific examples of UV curable polyol acrylate resins include trimethylolpropane triacrylate, ditrimethylolpropane tetraacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol hexaacrylate, alkyl-modified dipentaerythritol pentaacrylate, etc. Can be mentioned.

  Specific examples of photopolymerization initiators for these ultraviolet curable resins include benzoin and its derivatives, acetophenone, benzophenone, hydroxybenzophenone, Michler's ketone, α-amyloxime ester, thioxanthone, and derivatives thereof. You may use with a photosensitizer. The photopolymerization initiator can also be used as a photosensitizer. In addition, when using an epoxy acrylate photopolymerization initiator, a sensitizer such as n-butylamine, triethylamine, tri-n-butylphosphine can be used. The photopolymerization initiator or photosensitizer used in the ultraviolet curable resin composition is 0.1 to 15 parts by mass, preferably 1 to 10 parts by mass with respect to 100 parts by mass of the composition.

  Examples of the resin monomer may include general monomers such as methyl acrylate, ethyl acrylate, butyl acrylate, benzyl acrylate, cyclohexyl acrylate, vinyl acetate, and styrene as monomers having one unsaturated double bond. In addition, monomers having two or more unsaturated double bonds include ethylene glycol diacrylate, propylene glycol diacrylate, divinylbenzene, 1,4-cyclohexane diacrylate, 1,4-cyclohexyldimethyl adiacrylate, and the above trimethylolpropane. Examples thereof include triacrylate and pentaerythritol tetraacryl ester. As commercial products, Adekaoptomer KR / BY series: KR-400, KR-410, KR-550, KR-566, KR-567, BY-320B (manufactured by Asahi Denka Co., Ltd.); 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 (manufactured by Dainichi Seika Kogyo Co., Ltd.); KRM7033, KRM7039 KRM 7130, KRM 7131, UVECRYL 29201, UVECRYL 29202 (manufactured by Daicel UC Corporation); 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.); Sun Rad H-601, RC-750, RC-700, RC-600, RC-500, RC-611, RC-612 (Sanyo Chemical Industries Co., Ltd.); 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.), etc. Available. Examples of specific compounds include trimethylolpropane triacrylate, ditrimethylolpropane tetraacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol hexaacrylate, alkyl-modified dipentaerythritol pentaacrylate, and the like. .

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

  Inorganic particles include silicon oxide, titanium oxide, aluminum oxide, tin oxide, indium oxide, ITO, zinc oxide, zirconium oxide, magnesium oxide, calcium carbonate, calcium carbonate, talc, clay, calcined kaolin, calcined calcium silicate, water Mention may be made of Japanese 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. As organic particles, 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, A polyolefin resin powder, a polyester resin powder, a polyamide resin powder, a polyimide resin powder, a polyfluoroethylene resin powder, or the like can be added. Preferred particles include cross-linked polystyrene particles (for example, SX-130H, SX-200H, SX-350H manufactured by Soken Chemical) and polymethyl methacrylate-based particles (for example, MX150, MX300 manufactured by Soken Chemical).

  The average particle size of these particles is preferably 0.01 to 5 μm, and more preferably 0.1 to 5.0 μm, and further 0.1 to 4.0 μm is added to the coating composition for forming the hard coat layer. It is preferable from the stability of the composition.

  Moreover, you may contain 2 or more types of particle | grains from which a particle size differs. The proportion of the ultraviolet curable resin and the 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.

  Also, the hard coat layer is coated with a coating composition for forming the hard coat layer using a known method such as a gravure coater, dip coater, reverse coater, wire bar coater, die coater, ink jet method, etc. And can be formed by UV curing. 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.

As a light source for the ultraviolet curing treatment, any light source that generates ultraviolet light can be used without limitation. For example, 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. Irradiation conditions vary depending on each lamp, but the irradiation amount of ultraviolet rays is usually 5 to 500 mJ / cm ² , preferably 5 to 150 mJ / cm ² , and particularly preferably 20 to 100 mJ / cm ² .

  Moreover, when irradiating actinic rays including ultraviolet rays, it is preferably performed while applying tension in the film transport direction, and more preferably while applying tension in the width direction. The tension to be applied is preferably 30 to 300 N / m. The method for applying tension is not particularly limited, and tension may be applied in the transport direction on the back roll, or tension may be applied in the width direction or biaxial direction by a tenter. This makes it possible to obtain a film having further excellent flatness.

  The coating composition formed by the hard coat layer may contain a solvent. Examples of the organic solvent contained in the coating composition include hydrocarbons (toluene, xylene), alcohols (methanol, ethanol, isopropanol, butanol, cyclohexanol), and ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone). , Esters (methyl acetate, ethyl acetate, methyl lactate), glycol ethers, and other organic solvents may be appropriately selected or mixed for use.

  As the organic solvent, propylene glycol monoalkyl ether (1 to 4 carbon atoms of the alkyl group) or propylene glycol monoalkyl ether acetate (1 to 4 carbon atoms of the alkyl group) is preferable. Moreover, as content of an organic solvent, 5-80 mass% is preferable in a coating composition.

  The hard coat layer has a center line average roughness (Ra) defined by JIS B 0601 of 0.001 to 0.1 μm, a hard hard coat layer, or particles are added to adjust Ra to 0.1 to 1 μm. An antiglare hard coat layer is preferred. The center line average roughness (Ra) is preferably measured by an optical interference type surface roughness measuring instrument, for example, by using a non-contact surface fine shape measuring device “WYKO NT-2000” manufactured by WYKO. it can.

  Further, the hard coat layer preferably contains the silicone surfactant or polyoxyether compound described in the low refractive index layer. These enhance the applicability. Moreover, it is preferable to add these components in 0.01-3 mass% with respect to the solid content component in a coating liquid.

  Examples of the polyoxyether compound include polyoxyethylene alkyl ether, polyoxyethylene lauryl ether, polyoxyethylene cetyl ether, polyoxyethylene alkyl ether compounds such as polyoxyethylene stearyl ether, polyoxyethylene nonylphenyl ether, polyoxyethylene Polyoxyalkyl phenyl ether compounds such as ethylene octyl phenyl ether, polyoxyalkylene alkyl ether, polyoxyethylene higher alcohol ether, polyoxyethylene octyldodecyl ether and the like can be mentioned. Commercially available products of polyoxyethylene alkyl ether include Emulgen 1108, Emulgen 1118S-70 (above, manufactured by Kao Corporation), and commercially available products of polyoxyethylene lauryl ether include Emulgen 103, Emulgen 104P, Emulgen 105, Emulgen 106, Emulgen 108, Emulgen 109P, Emulgen 120, Emulgen 123P, Emulgen 147, Emulgen 150, Emulgen 130K (above, manufactured by Kao Corporation), and polyoxyethylene cetyl ether are commercially available products of Emulgen 210P, Emulgen 220 (above, manufactured by Kao Corporation) As commercially available products of polyoxyethylene stearyl ether, Emulgen 220, Emulgen 306P (above, manufactured by Kao Corporation), and commercially available products of polyoxyalkylene alkyl ether include Examples of commercially available products of Rugen LS-106, Emulgen LS-110, Emulgen LS-114, Emulgen MS-110 (manufactured by Kao Corporation) polyoxyethylene higher alcohol ether include Emulgen 705, Emulgen 707, and Emulgen 709. .

  Among these nonionic polyoxyether compounds, polyoxyethylene oleyl ether compounds are preferable, and are compounds represented by the following general formula (4).

_{C 18 H 35 -O (C 2} H 4 O) nH ... (4)
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. Moreover, the compound of the said General formula (4) is obtained by making ethylene oxide and oleyl alcohol react.

  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] (above, manufactured by 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.

  The mass ratio of the silicone surfactant and the polyoxyether compound in the hard coat layer is 1.0: 1.0 to 0.10: 1.0, more preferably 0.70: 1.0 to It is 0.20: 1.0, and it is preferable when it contains by the said mass ratio, when obtaining an effect.

  The preferable content of the nonionic polyoxyether compound and the silicone surfactant in the hard coat layer is preferably 0.1% by mass to 8.0% by mass, more preferably 0.0% by mass in terms of the total content of both. It is 2 mass%-4.0 mass%, and it exists stably in a hard-coat layer by adding in this range.

  Moreover, you may use together the said fluorosurfactant, an acryl-type copolymer, an acetylene glycol type compound or a nonionic surfactant, a radically polymerizable nonionic surfactant, etc.

  Nonionic surfactants include polyoxyethylene monolaurate, polyoxyethylene monostearate, polyoxyalkyl ester compounds such as polyoxyethylene monooleate, sorbitan monolaurate, sorbitan monostearate, sorbitan monooleate, etc. Sorbitan ester compounds, and the like.

  Examples of the acetylene glycol compounds include Surfinol 104E, Surfinol 104PA, Surfinol 420, Surfinol 440, and Dynal 604 (manufactured by Nissin Chemical Industry Co., Ltd.).

  Examples of the radical polymerizable nonionic surfactant include polyoxyalkylene alkyl such as “RMA-564”, “RMA-568”, “RMA-1114” [trade name, manufactured by Nippon Emulsifier Co., Ltd.]. Examples include phenyl ether (meth) acrylate polymerizable surfactants.

  The hard coat layer may have a multilayer structure of two or more layers. One of the layers may be, for example, a so-called antistatic layer containing conductive particles or an ionic polymer, or a color tone adjusting agent (dye having a color tone adjusting function as a color correction filter for various display elements. Alternatively, a pigment or the like may be contained, or an electromagnetic wave blocking agent or an infrared absorber may be contained to have each function.

(Back coat layer)
In the antireflection film of the present invention, a back coat layer may be provided on the surface opposite to the side provided with the hard coat layer. The back coat layer is provided in order to correct curling caused by providing the antireflection layer. 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, and in this case, particles of an inorganic compound or an organic compound are added to the back coat layer coating composition in order to provide an anti-blocking function. It is preferable.

  As 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 particles include, for example, Aerosil R972, R972V, R974, R812, 200, 200V, 300, R202, OX50, TT600 (manufactured by Nippon Aerosil Co., Ltd.), Seahoster KE-P10, KE-P30, KE- P50, KE-P100, KE-P150, and KE-P250 (above, manufactured by Nippon Shokubai Co., Ltd.) are commercially available and can be used.

  Examples of organic compounds include silicone resins, fluororesins, and acrylic resins. 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.) Are commercially available and can be used.

  Among these, Aerosil 200V, Aerosil R972V, Seahoster KE-P30, KE-P50, and KE-P100 are particularly preferably used because they have a large anti-blocking effect while keeping haze low. The antireflection film used in the present invention preferably has a dynamic friction coefficient on the back side of the active energy ray-curable resin layer of 0.9 or less, particularly 0.1 to 0.9.

  The particles contained in the backcoat layer are 0.1 to 50% by weight, preferably 0.1 to 10% by weight, based on the binder. When the back coat layer is provided, the increase in haze 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.

  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 Fine methacrylic monomer 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 cellulose ester such as cellulose diacetate and cellulose acetate propionate and an acrylic resin, and using an acrylic resin particle, the refractive index of the particle and the binder By setting the difference to be less than 0 to 0.02, a highly transparent back coat layer can be obtained.

  These coating compositions are preferably applied to the surface of the transparent film with a wet film thickness of 1 to 100 μm using a gravure coater, dip coater, reverse coater, wire bar coater, die coater, spray coating, ink jet coating or the like. In particular, the thickness is preferably 5 to 30 μm.

  Moreover, a backcoat layer is formed by heat-drying after application | coating and carrying out the hardening process as needed. The content described in the low refractive index layer can be used for the curing treatment.

  The backcoat layer can be applied in two or more steps. Further, the backcoat layer may also serve as an easy adhesion layer for improving the adhesion with the polarizer.

  When each layer is formed by coating as described above, the transparent film is unwound in a roll form with a width of 1.4 to 4 m, applied, dried and cured, and then rolled. It is preferably wound up. Moreover, after laminating | stacking an antireflection layer, it is manufactured by the manufacturing method which heat-processes at 50-160 degreeC in the state wound up by roll shape, and the efficiency and stability at the time of apply | coating an antireflection film long It is preferable from the property. The heat treatment period may be appropriately determined depending on the set temperature. For example, if it is 50 ° C., it is preferably a period of 3 days or more and less than 30 days, and if it is 160 ° C., a range of 10 minutes or more and 1 day or less is preferable. . Usually, it is preferably set at a relatively low temperature so that the heat treatment effect on the outside of the winding, the center of the winding, and the core is not biased, and it is preferably performed at around 50 to 60 ° C. for about 7 days.

  In order to stably perform the heat treatment, it is necessary to perform in a place where the temperature and humidity can be adjusted, and it is preferable to perform in a heat treatment chamber such as a clean room free from dust.

  The winding core for winding the antireflection film into a roll is not particularly limited as long as it is a cylindrical core, but is preferably a hollow plastic core, and the plastic material is a heat resistant plastic that can withstand heat treatment temperatures. Preferred examples include resins such as phenol resins, xylene resins, melamine resins, polyester resins, and epoxy resins. A thermosetting resin reinforced with a filler such as glass fiber is preferable. 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.

(Reflectivity of antireflection film)
The reflectance of the antireflection film of the present invention can be measured with a spectrophotometer. At that time, after roughening the back side of the measurement side of the sample, light absorption treatment is performed using a black spray, and then reflected light in the visible light region (400 to 700 nm) is measured. The lower the reflectivity, the better. However, the average value in the visible light wavelength is preferably 2.5% or less, and the minimum reflectivity is preferably 1.5% or less. Moreover, if a reflectance is 2.5% or less, it can be regarded as the antireflection film of this invention.

  It is preferable to have a flat reflection spectrum in the visible light wavelength region.

  Also, the reflection hue on the surface of the image display device subjected to the antireflection treatment is often colored red or blue because the reflectance of the short wavelength region or the long wavelength region is high in the visible light region due to the design of the antireflection film. However, the color tone of 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, the generally preferred reflection hue range is the XYZ color system (CIE 1931 color system).
0.17 ≦ x ≦ 0.33,
0.10 ≦ y ≦ 0.33.

  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.

  It is preferable to perform a surface treatment before applying 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 is a treatment performed by applying a high voltage of 1 kV or higher between the electrodes under atmospheric pressure and discharging it, and using a device commercially available from Kasuga Electric Co., Ltd. or Toyo Electric Co., Ltd. Can be done. 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 used in the present invention is a frequency of 20 kHz to 100 kHz, 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 1 to 5 W · min. / M ² but ² to 4 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 is opened, 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. Furthermore, when the film is transported and continuously processed, the film comes into contact with the electrodes and scratches are generated.

  The alkali treatment method is not particularly limited as long as it is a method in which a film coated with a hard coat layer is immersed in an alkaline aqueous solution.

  As the aqueous alkali solution, an aqueous sodium hydroxide solution, an aqueous potassium hydroxide solution, an aqueous ammonia solution or the like can be used, and an aqueous sodium hydroxide solution is particularly preferable.

  The alkali concentration of the aqueous alkali solution, for example, sodium hydroxide concentration is preferably 0.1 to 25% by mass, and more preferably 0.5 to 15% by mass. The alkali treatment temperature is usually 10 to 80 ° C, preferably 20 to 60 ° C.

  The alkali treatment time is 5 seconds to 5 minutes, preferably 30 seconds to 3 minutes. The film after the alkali treatment is preferably neutralized with acidic water and then thoroughly washed with water.

(Transparent film substrate)
The transparent film base material which consists of a transparent resin film used for this invention is demonstrated.

  As a transparent film base material, it is preferable that the production is easy, the adhesiveness with the actinic radiation curable resin layer is good, the optical isotropic property, the optical transparency, etc. Can be mentioned.

  The term “transparent” as used herein means that the visible light transmittance is 60% or more, preferably 80% or more, and particularly preferably 90% or more.

  Although it will not specifically limit if it has said property, For example, cellulose ester films, such as a cellulose diacetate film, a cellulose triacetate film, a cellulose acetate propionate film, a cellulose acetate butyrate film, a polyester film, a polycarbonate Film, polyarylate film, polysulfone (including polyethersulfone) film, polyester film such as polyethylene terephthalate and polyethylene naphthalate, polyethylene film, polypropylene film, cellophane, polyvinylidene chloride film, polyvinyl alcohol film, ethylene vinyl alcohol Film, syndiotactic polystyrene film, cycloolefin polymer fill (Arton (manufactured by JSR), Zeonex, Zeonore (manufactured by Nippon Zeon)), polyvinyl acetal, polymethylpentene film, polyether ketone film, polyether ketone imide film, polyamide film, fluororesin film, nylon film, A polymethyl methacrylate film, an acrylic film, a glass plate, etc. can be mentioned.

  Among them, a cellulose ester film, a polycarbonate film, a polysulfone (including polyether sulfone) film, and a cycloolefin polymer film are preferable. In the present invention, as the cellulose ester film, for example, KC8UX2MW, KC4UX, KC5UX, KC4UY , KC8UY, KC12UR, KC4UEW, KC8UCR-3, KC8UCR-4, KC8UCR-5, KC4FR-1, KC4FR-2 (manufactured by Konica Minolta Opto Co., Ltd.) are in terms of manufacturing, cost, transparency, adhesiveness, etc. Are preferably used.

  These films may be films produced by melt casting film formation or films produced by solution casting film formation.

  As the transparent film substrate, it is preferable to use a cellulose ester film (hereinafter also referred to as a cellulose ester film). As the cellulose ester, cellulose acetate, cellulose acetate butyrate, and cellulose acetate propionate are preferable. Among them, cellulose acetate butyrate, cellulose acetate phthalate, and cellulose acetate propionate are preferably used.

  In particular, when the substitution degree of the acetyl group is X and the substitution degree of the propionyl group or butyryl group is Y, it is preferable to use a cellulose ester film in which X and Y are in the following ranges.

2.3 ≦ X + Y ≦ 3.0 0.1 ≦ Y ≦ 2.0
In particular, it is preferable that 2.5 ≦ X + Y ≦ 2.9 3 ≦ Y ≦ 1.2.

  Hereinafter, the cellulose ester film which is a preferable transparent film will be described in detail.

  The cellulose ester film preferably has a free volume radius of 0.250 to 0.310 nm determined by the positron annihilation lifetime method in order to obtain an antireflection film with little flatness due to heat treatment and excellent flatness. Furthermore, it is more preferable that it is a cellulose-ester film whose total free volume parameter is 1.0-2.0.

  In addition, the said free volume represents the space | gap part which is not occupied by the molecular chain of a transparent film. This can be measured using the positron annihilation lifetime method. Specifically, by measuring the time from the incidence of positrons to the sample until annihilation, non-destructively observing information on the vacancies, the size of the free volume, the number concentration, etc. from the annihilation lifetime Can be sought.

(Measurement of free volume radius and total free volume parameters by positron annihilation lifetime method)
The positron annihilation lifetime and relative intensity were measured under the following measurement conditions.

(Measurement condition)
Positron beam source: 22 NaCl (strength 1.85 MBq)
Gamma ray detector: Plastic scintillator + photomultiplier tube Time resolution: 290ps
Measurement temperature: 23 ° C
Total count: 1 million counts Sample size: 20 mm x 15 mm
Twenty pieces of sample sections cut to 20 mm × 15 mm were stacked to a thickness of about 2 mm. The sample was vacuum dried for 24 hours before measurement.

Irradiation area: About 10mmφ
Time per channel: 23.3ps / ch
According to the above measurement conditions, carried out positron annihilation lifetime spectroscopy, and 3 component analysis by non-linear least squares method, starting with the lowest annihilation lifetime, tau _1, tau _2, and tau _3, I ₁ the intensity corresponding thereto, I ₂ and I ₃ (I ₁ + I ₂ + I ₃ = 100%).

From the average annihilation lifetime τ3 having the longest lifetime, the free volume radius R ₃ (nm) was determined using the following formula. τ ₃ corresponds to positron annihilation in the pores, it is believed that the pore size as τ ₃ is large is large.

τ ₃ = (1/2) [1- {R ₃ / (R ₃ +0.166)}
+ (1 / 2π) sin {2πR ₃ / (R ₃ +0.166)}] − 1
Here, 0.166 (nm) corresponds to the thickness of the electron layer leached from the hole wall.

Furthermore, the total free volume parameter _Vp was determined by the following equation.

V ₃ = {(4/3) π (R ₃ ) 3} (nm ³ )
V _p = I ₃ (%) × V ₃ (nm ³ )
Here, I ₃ (%) corresponds to the relative number concentration of vacancies, and thus V _p corresponds to the relative amount of vacancies.

  The above measurement was repeated twice, and the average value was obtained.

  For example, MATERIAL STAGE vol.4, No.5 2004 p21-25, Toray Research Center THE TRC NEWS No.80 (Jul.2002) p20-22, "Bunseki" (1988, pp.11- 20) “Evaluation of free volume of polymer by positron annihilation method” is published and can be referred to.

  The free volume radius in the cellulose ester film is 0.250 to 0.315 nm, preferably 0.250 to 0.310 nm, and a more preferable range is 0.285 to 0.305 nm. The free volume radius is less than 0.250 nm. When the free volume radius is 0.250 to 0.315 nm, the base material deformation with respect to the heat treatment is small, and an antireflection film excellent in flatness can be obtained.

  The raw material of the cellulose ester forming the cellulose ester film is not particularly limited, and examples thereof include cotton linter, wood pulp (derived from coniferous tree, derived from broadleaf tree), kenaf and the like. Moreover, the cellulose ester obtained from them can be mixed and used in arbitrary ratios, respectively. When the acylating agent is an acid anhydride (acetic anhydride, propionic anhydride, butyric anhydride), these cellulose esters use an organic solvent such as acetic acid or an organic solvent such as methylene chloride, and It can be obtained by reacting with a cellulose raw material using a protic catalyst.

When the acylating agent is acid chloride (CH ₃ COCl, C ₂ H ₅ COCl, C ₃ H ₇ COCl), the reaction is carried out using a basic compound such as an amine as a catalyst. Specifically, it can be synthesized with reference to the method described in JP-A-10-45804.

  In addition, the cellulose ester used in the present invention is obtained by mixing and reacting the amount of the acylating agent in accordance with the degree of substitution. In the cellulose ester, these acylating agents react with hydroxyl groups of cellulose molecules. Cellulose molecules are composed of many glucose units linked together, and the glucose unit has three hydroxyl groups. The number of acyl groups derived from these three hydroxyl groups is called the degree of substitution (mol%). For example, cellulose triacetate has acetyl groups bonded to all three hydroxyl groups of the glucose unit (actually 2.6 to 3.0).

  The measuring method of the substitution degree of an acyl group can be measured according to the rule of ASTM-D817-96.

  The number average molecular weight of the cellulose ester is preferably from 50,000 to 250,000 because the mechanical strength when molded is high and an appropriate dope viscosity is obtained, and more preferably from 80,000 to 150,000.

  Cellulose ester film is a solution in which a cellulose ester solution (dope), commonly referred to as a solution casting film forming method, is pressed onto a casting support of an endless metal belt or rotating metal drum, for example. It is manufactured by casting a dope from a die and forming a film.

  As the organic solvent used for preparing these dopes, it is preferable that the cellulose ester can be dissolved and has an appropriate boiling point. For example, methylene chloride, methyl acetate, ethyl acetate, amyl acetate, methyl acetoacetate, acetone, tetrahydrofuran 1,3-dioxolane, 1,4-dioxane, cyclohexanone, ethyl formate, 2,2,2-trifluoroethanol, 2,2,3,3-tetrafluoro-1-propanol, 1,3-difluoro-2 -Propanol, 1,1,1,3,3,3-hexafluoro-2-methyl-2-propanol, 1,1,1,3,3,3-hexafluoro-2-propanol, 2,2,3 , 3,3-pentafluoro-1-propanol, nitroethane, 1,3-dimethyl-2-imidazolidinone, etc. Can, organic halogen compounds such as methylene chloride, dioxolane derivatives, methyl acetate, ethyl acetate, acetone, methyl acetoacetate, and the like are preferable organic solvents (i.e., good solvent), and as.

  Moreover, as shown in the following film forming process, it is used from the viewpoint of preventing foaming in the web when the solvent is dried from the web (dope film) formed on the casting support in the solvent evaporation process. The boiling point of the organic solvent is preferably 30 to 80 ° C. For example, the good solvent described above has a boiling point of methylene chloride (boiling point 40.4 ° C), methyl acetate (boiling point 56.32 ° C), acetone (boiling point 56.56 ° C). 3 ° C.), ethyl acetate (boiling point 76.82 ° C.) and the like.

  Among the above good solvents, methylene chloride or methyl acetate having excellent solubility is preferably used.

  In addition to the organic solvent, it is preferable to contain 0.1 to 40% by mass of an alcohol having 1 to 4 carbon atoms. It is particularly preferable that the alcohol is contained at 5 to 30% by mass.

  After casting the above dope onto the casting support, the solvent starts to evaporate and the alcohol ratio increases and the web (dope film) gels, making the web strong and peeling from the casting support. When it is used as a gelling solvent for facilitating or the ratio of these is small, it also has a role of promoting the dissolution of the cellulose ester of the non-chlorine organic solvent.

  Examples of the alcohol having 1 to 4 carbon atoms include methanol, ethanol, n-propanol, iso-propanol, n-butanol, sec-butanol, tert-butanol and the like.

  Of these solvents, ethanol is preferred because it has good dope stability, relatively low boiling point, good drying properties, and no toxicity. It is preferable to use a solvent containing 5 to 30% by mass of ethanol with respect to 70 to 95% by mass of methylene chloride. Methyl acetate can be used in place of methylene chloride. At this time, the dope may be prepared by a cooling dissolution method.

  The cellulose ester film preferably contains the following plasticizer. Examples of plasticizers include phosphate ester plasticizers, polyhydric alcohol ester plasticizers, phthalate ester plasticizers, trimellitic ester plasticizers, pyromellitic acid plasticizers, glycolate plasticizers, Citric acid ester plasticizers, polyester plasticizers, fatty acid ester plasticizers, polycarboxylic acid ester plasticizers, and the like can be preferably used.

  Among these, polyhydric alcohol ester plasticizers, phthalate ester plasticizers, citrate ester plasticizers, fatty acid ester plasticizers, glycolate plasticizers, polycarboxylic acid ester plasticizers, and the like are preferable. In particular, it is preferable to use a polyhydric alcohol ester plasticizer, which is preferable because the pencil hardness of the hard coat layer can be stably obtained as 4H or more.

  The polyhydric alcohol ester plasticizer is a plasticizer composed of an ester of a divalent or higher aliphatic polyhydric alcohol and a monocarboxylic acid, and preferably has an aromatic ring or a cycloalkyl ring in the molecule. Preferably it is a 2-20 valent aliphatic polyhydric alcohol ester.

  The polyhydric alcohol preferably used in the present invention is represented by the following general formula (5).

R ^1- (OH) n (5)
In the formula, R ¹ represents an n-valent organic group, n represents a positive integer of 2 or more, and an OH group represents an alcoholic and / or phenolic hydroxyl group.

  Examples of preferred polyhydric alcohols include the following, but the present invention is not limited to these.

  Adonitol, arabitol, ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, 1,2-propanediol, 1,3-propanediol, dipropylene glycol, tripropylene glycol, 1,2-butanediol, 1,3- Butanediol, 1,4-butanediol, dibutylene glycol, 1,2,4-butanetriol, 1,5-pentanediol, 1,6-hexanediol, hexanetriol, galactitol, mannitol, 3-methylpentane- Examples include 1,3,5-triol, pinacol, sorbitol, trimethylolpropane, trimethylolethane, xylitol and the like. In particular, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, sorbitol, trimethylolpropane, and xylitol are preferable.

  There is no restriction | limiting in particular as monocarboxylic acid used for polyhydric alcohol ester, Well-known aliphatic monocarboxylic acid, alicyclic monocarboxylic acid, aromatic monocarboxylic acid, etc. can be used. Use of an alicyclic monocarboxylic acid or aromatic monocarboxylic acid is preferred in terms of improving moisture permeability and retention.

  Examples of preferred monocarboxylic acids include the following, but the present invention is not limited to these.

  As the aliphatic monocarboxylic acid, a fatty acid having a straight chain or side chain having 1 to 32 carbon atoms can be preferably used. The number of carbon atoms is more preferably 1-20, and particularly preferably 1-10. When acetic acid is contained, the compatibility with the cellulose ester is increased, and it is also preferable to use a mixture of acetic acid and another monocarboxylic acid.

  Preferred aliphatic monocarboxylic acids include acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, enanthic acid, caprylic acid, pelargonic acid, capric acid, 2-ethyl-hexanoic acid, undecylic acid, lauric acid, tridecylic acid, Saturated fatty acids such as myristic acid, pentadecylic acid, palmitic acid, heptadecylic acid, stearic acid, nonadecanoic acid, arachidic acid, behenic acid, lignoceric acid, serotic acid, heptacosanoic acid, montanic acid, melicic acid, laccelic acid, undecylenic acid, olein Examples thereof include unsaturated fatty acids such as acid, sorbic acid, linoleic acid, linolenic acid, and arachidonic acid.

  Examples of preferred alicyclic monocarboxylic acids include cyclopentane carboxylic acid, cyclohexane carboxylic acid, cyclooctane carboxylic acid, or derivatives thereof.

  Examples of preferred aromatic monocarboxylic acids include those in which 1 to 3 alkoxy groups such as an alkyl group, a methoxy group or an ethoxy group are introduced into the benzene ring of benzoic acid such as benzoic acid or toluic acid, biphenylcarboxylic acid, Examples thereof include aromatic monocarboxylic acids having two or more benzene rings such as naphthalenecarboxylic acid and tetralincarboxylic acid, or derivatives thereof. Benzoic acid is particularly preferable.

  The molecular weight of the polyhydric alcohol ester is not particularly limited, but is preferably 300 to 1500, and more preferably 350 to 750. A higher molecular weight is preferred because it is less likely to volatilize, and a smaller one is preferred in terms of moisture permeability and compatibility with cellulose ester.

  The carboxylic acid used for the polyhydric alcohol ester may be one kind or a mixture of two or more kinds. Moreover, all the OH groups in the polyhydric alcohol may be esterified, or a part of the OH groups may be left as they are.

Below, the specific compound of a polyhydric alcohol ester is illustrated.

  The glycolate plasticizer is not particularly limited, but alkylphthalylalkyl glycolates can be preferably used. Examples of alkyl phthalyl alkyl glycolates include methyl phthalyl methyl glycolate, ethyl phthalyl ethyl glycolate, propyl phthalyl propyl glycolate, butyl phthalyl butyl glycolate, octyl phthalyl octyl glycolate, methyl phthalyl ethyl Glycolate, ethyl phthalyl methyl glycolate, ethyl phthalyl propyl glycolate, methyl phthalyl butyl glycolate, ethyl phthalyl butyl glycolate, butyl phthalyl methyl glycolate, butyl phthalyl ethyl glycolate, propyl phthalyl butyl glycol Butyl phthalyl propyl glycolate, methyl phthalyl octyl glycolate, ethyl phthalyl octyl glycolate, octyl phthalyl methyl glycolate, octyl phthalate Ethyl glycolate, and the like.

  Examples of the phthalate ester plasticizer include diethyl phthalate, dimethoxyethyl phthalate, dimethyl phthalate, dioctyl phthalate, dibutyl phthalate, di-2-ethylhexyl phthalate, dioctyl phthalate, dicyclohexyl phthalate, and dicyclohexyl terephthalate.

  Examples of the citrate plasticizer include acetyl trimethyl citrate, acetyl triethyl citrate, and acetyl tributyl citrate.

  Examples of fatty acid ester plasticizers include butyl oleate, methylacetyl ricinoleate, and dibutyl sebacate.

  Polycarboxylic acid ester plasticizers can also be preferably used. Specifically, it is preferable to add the polyvalent carboxylic acid ester described in paragraphs [0015] to [0020] of JP-A No. 2002-265639 as one of the plasticizers.

    In addition, phosphate plasticizers can also be used as other plasticizers, such as triphenyl phosphate, tricresyl phosphate, cresyl diphenyl phosphate, octyl diphenyl phosphate, diphenyl biphenyl phosphate, trioctyl phosphate, tributyl phosphate, etc. It is done.

  In addition, it is also preferable to contain an acrylic polymer described in JP-A-2003-12859.

(Acrylic polymer)
It is preferable that a cellulose-ester film contains the acrylic polymer whose weight average molecular weight which shows negative orientation birefringence with respect to a extending | stretching direction is 500-30000.

  By controlling the composition of the polymer so that the weight average molecular weight of the polymer is 500 or more and 30000 or less, the compatibility between the cellulose ester and the polymer can be improved.

  In particular, for an acrylic polymer, an acrylic polymer having an aromatic ring in the side chain, or an acrylic polymer having a cyclohexyl group in the side chain, if the weight average molecular weight is preferably 500 or more and 10,000 or less, in addition to the above, The transparency of the cellulose ester film is excellent, the moisture permeability is extremely low, and it exhibits excellent performance as an antireflection film.

  Since the polymer has a weight average molecular weight of 500 or more and 30000 or less, it is considered to be between the oligomer and the low molecular weight polymer. In order to synthesize such a polymer, it is difficult to control the molecular weight in normal polymerization, and it is desirable to use a method that can align the molecular weight as much as possible by a method that does not increase the molecular weight.

  Such polymerization methods include a method using a peroxide polymerization initiator such as cumene peroxide and t-butyl hydroperoxide, a method using a polymerization initiator in a larger amount than normal polymerization, and a mercapto compound in addition to the polymerization initiator. And a method using a chain transfer agent such as carbon tetrachloride, a method using a polymerization terminator such as benzoquinone and dinitrobenzene in addition to the polymerization initiator, and further disclosed in JP 2000-128911 or 2000-344823 Examples thereof include a compound having one thiol group and a secondary hydroxyl group, or a bulk polymerization method using a polymerization catalyst in which the compound and an organometallic compound are used in combination. In particular, the method described in the publication is preferable.

  In the present invention, the acrylic polymer refers to a homopolymer or a copolymer of acrylic acid or methacrylic acid alkyl ester having no monomer unit having an aromatic ring or a cyclohexyl group. An acrylic polymer having an aromatic ring in the side chain is an acrylic polymer that always contains an acrylic acid or methacrylic acid ester monomer unit having an aromatic ring.

  The acrylic polymer having a cyclohexyl group in the side chain is an acrylic polymer containing an acrylic acid or methacrylic acid ester monomer unit having a cyclohexyl group.

  Examples of the acrylate monomer having no aromatic ring and cyclohexyl group include, for example, methyl acrylate, ethyl acrylate, propyl acrylate (i-, n-), butyl acrylate (n-, i-, s-, t-), pentyl acrylate (n-, i-, s-), hexyl acrylate (n-, i-), heptyl acrylate (n-, i-), octyl acrylate (n-, i-) , Nonyl acrylate (n-, i-), myristyl acrylate (n-, i-), acrylic acid (2-ethylhexyl), acrylic acid (ε-caprolactone), acrylic acid (2-hydroxyethyl), acrylic acid (2-hydroxypropyl), acrylic acid (3-hydroxypropyl), acrylic acid (4-hydroxybutyl), acrylic acid (2-hydroxybutyl), acrylic acid 2-methoxy-ethyl), acrylic acid (2-ethoxyethyl), or the acrylic acid ester may include those obtained by changing the methacrylic acid ester.

  The acrylic polymer is a homopolymer or copolymer of the above-mentioned monomers, but the acrylic acid methyl ester monomer unit preferably has 30% by mass or more, and the methacrylic acid methyl ester monomer unit has 40% by mass or more. preferable. In particular, a homopolymer of methyl acrylate or methyl methacrylate is preferred.

  Examples of acrylic acid or methacrylic acid ester monomers having an aromatic ring include phenyl acrylate, phenyl methacrylate, acrylic acid (2 or 4-chlorophenyl), methacrylic acid (2 or 4-chlorophenyl), and acrylic acid (2 or 3 Or 4-ethoxycarbonylphenyl), methacrylic acid (2 or 3 or 4-ethoxycarbonylphenyl), acrylic acid (o or m or p-tolyl), methacrylic acid (o or m or p-tolyl), benzyl acrylate, Benzyl methacrylate, phenethyl acrylate, phenethyl methacrylate, acrylic acid (2-naphthyl) and the like can be mentioned, but benzyl acrylate, benzyl methacrylate, phenethyl acrylate, and phenethyl methacrylate are preferably used. That.

  Among acrylic polymers having an aromatic ring in the side chain, the acrylic acid or methacrylic acid ester monomer unit having an aromatic ring has 20 to 40% by mass, and the acrylic acid or methacrylic acid methyl ester monomer unit is 50 to 80% by mass. % Is preferable. The polymer preferably has 2 to 20% by mass of acrylic acid or methacrylic acid ester monomer units having a hydroxyl group.

  Examples of the acrylate monomer having a cyclohexyl group include cyclohexyl acrylate, cyclohexyl methacrylate, acrylic acid (4-methylcyclohexyl), methacrylic acid (4-methylcyclohexyl), acrylic acid (4-ethylcyclohexyl), and methacrylic acid. (4-ethylcyclohexyl) and the like can be mentioned, but cyclohexyl acrylate and cyclohexyl methacrylate can be preferably used.

  In the acrylic polymer having a cyclohexyl group in the side chain, the acrylic acid or methacrylic acid ester monomer unit having a cyclohexyl group has 20 to 40% by mass and preferably 50 to 80% by mass. Moreover, it is preferable to have 2-20 mass% of acrylic acid or methacrylic acid ester monomer units having a hydroxyl group in the polymer.

  Polymers obtained by polymerizing the above ethylenically unsaturated monomers, acrylic polymers, acrylic polymers having an aromatic ring in the side chain, and acrylic polymers having a cyclohexyl group in the side chain are all excellent in compatibility with the cellulose resin.

  In the case of an acrylic acid or methacrylic acid ester monomer having these hydroxyl groups, it is not a homopolymer but a structural unit of a copolymer. In this case, it is preferable that the acrylic acid or methacrylic acid ester monomer unit having a hydroxyl group is contained in the acrylic polymer in an amount of 2 to 20% by mass.

  A polymer having a hydroxyl group in the side chain can also be preferably used. The monomer unit having a hydroxyl group is the same as the monomer described above, but acrylic acid or methacrylic acid ester is preferable. For example, acrylic acid (2-hydroxyethyl), acrylic acid (2-hydroxypropyl), acrylic acid (3 -Hydroxypropyl), acrylic acid (4-hydroxybutyl), acrylic acid (2-hydroxybutyl), acrylic acid-p-hydroxymethylphenyl, acrylic acid-p- (2-hydroxyethyl) phenyl, or these acrylic acids. The thing replaced by methacrylic acid can be mentioned, Preferably, it is 2-hydroxyethyl acrylate and 2-hydroxyethyl methacrylate. The acrylic acid ester or methacrylic acid ester monomer unit having a hydroxyl group in the polymer is preferably contained in the polymer in an amount of 2 to 20% by mass, more preferably 2 to 10% by mass.

  A polymer containing 2 to 20% by mass of the above-mentioned monomer unit having a hydroxyl group, of course, is excellent in compatibility with cellulose ester, retention, dimensional stability, low moisture permeability, and polarized light. It is particularly excellent in adhesiveness with a polarizer as a plate protective film, and has the effect of improving the durability of the polarizing plate.

  The method of having a hydroxyl group at at least one terminal of the main chain of the acrylic polymer is not particularly limited as long as it has a hydroxyl group at the terminal of the main chain, but azobis (2-hydroxyethylbutyrate) A method using a radical polymerization initiator having such a hydroxyl group, a method using a chain transfer agent having a hydroxyl group such as 2-mercaptoethanol, a method using a polymerization terminator having a hydroxyl group, and terminating a hydroxyl group by living ion polymerization. And a method comprising a compound having one thiol group and a secondary hydroxyl group as described in Japanese Patent Application Laid-Open No. 2000-344823, or a combination of the compound and an organometallic compound. It can be obtained by a bulk polymerization method using a catalyst, and the method described in the publication is particularly preferable.

  The polymer produced by the method related to the description in this publication is commercially available as Act Flow Series manufactured by Soken Chemical Co., Ltd., and can be preferably used. The polymer having a hydroxyl group at the terminal and / or the polymer having a hydroxyl group in a side chain has an effect of significantly improving the compatibility and transparency of the polymer.

  Furthermore, a polymer using styrene as an ethylenically unsaturated monomer exhibiting negative orientation birefringence with respect to the stretching direction is preferable in order to develop negative refraction. Examples of styrenes include styrene, methyl styrene, dimethyl styrene, trimethyl styrene, ethyl styrene, isopropyl styrene, chloromethyl styrene, methoxy styrene, acetoxy styrene, chloro styrene, dichloro styrene, bromo styrene, and vinyl benzoic acid methyl ester. Although it is mentioned, it is not a thing limited to these.

  It may be copolymerized with the exemplified monomers listed as the unsaturated ethylenic monomer, or may be used by being dissolved in a cellulose ester using two or more kinds of the above polymers for the purpose of controlling birefringence.

  In addition, the cellulose ester film contains an ethylenically unsaturated monomer Xa having no aromatic ring and a hydrophilic group in the molecule and an ethylenically unsaturated monomer Xb having no aromatic ring in the molecule and having a hydrophilic group. Polymer Y having a weight average molecular weight of 5,000 to 30,000 obtained by polymerization, and more preferably a polymer Y having a weight average molecular weight of 500 to 3,000 obtained by polymerizing an ethylenically unsaturated monomer Ya having no aromatic ring It is preferable to contain.

(Polymer X, Polymer Y)
The polymer X used in the present invention includes an ethylenically unsaturated monomer Xa having no aromatic ring and a hydrophilic group in the molecule, and an ethylenically unsaturated monomer Xb having no aromatic ring in the molecule and having a hydrophilic group. Is a polymer having a weight average molecular weight of 5,000 or more and 30,000 or less obtained by copolymerization.

  Preferably, Xa is an acrylic or methacrylic monomer that does not have an aromatic ring and a hydrophilic group in the molecule, and Xb is an acrylic or methacrylic monomer that does not have an aromatic ring in the molecule and has a hydrophilic group.

  The polymer X is represented by the following general formula (6).

-(Xa) m- (Xb) n- (Xc) p- (6)
More preferably, it is a polymer represented by the following general formula (7).

_{^{- [CH 2 -C (-R 1}} ) (- CO 2 R 2)] m- [CH 2 -C (-R 3)
^{_{(-CO 2 R 4 -OH) -}} ] n- [Xc] p- ... (7)
(In the formula, R ¹ and R ³ represent H or CH _3. R ² represents an alkyl group having 1 to 12 carbon atoms and a cycloalkyl group. R ⁴ represents —CH ₂ —, —C ₂ H ₄ —. Or -C ₃ H _6- , Xc represents a monomer unit polymerizable to Xa and Xb, m, n and p represent molar composition ratios, provided that m ≠ 0, n ≠ 0, k ≠ 0, m + n + p = 100.)
In the present invention, monomers as monomer units constituting the acrylic polymer X are listed below, but are not limited thereto.

  In the acrylic polymer X, the hydrophilic group means a group having a hydroxyl group or an ethylene oxide chain.

  The ethylenically unsaturated monomer Xa having no aromatic ring and no hydrophilic group in the molecule includes, for example, methyl acrylate, ethyl acrylate, propyl acrylate (i-, n-), butyl acrylate (n-, i-, s-, t-), pentyl acrylate (n-, i-, s-), hexyl acrylate (n-, i-), heptyl acrylate (n-, i-), octyl acrylate (n-, i-), nonyl acrylate (n-, i-), myristyl acrylate (n-, i-), acrylic acid (2-ethylhexyl), acrylic acid (ε-caprolactone), etc., or the above acrylate ester What changed to the methacrylic acid ester can be mentioned.

  Among these, methyl acrylate, ethyl acrylate, methyl methacrylate, ethyl methacrylate, and propyl methacrylate (i-, n-) are preferable.

  The ethylenically unsaturated monomer Xb having no aromatic ring in the molecule and having a hydrophilic group is preferably acrylic acid or methacrylic acid ester as a monomer unit having a hydroxyl group. For example, acrylic acid (2-hydroxyethyl), acrylic Examples include acid (2-hydroxypropyl), acrylic acid (3-hydroxypropyl), acrylic acid (4-hydroxybutyl), acrylic acid (2-hydroxybutyl), or those obtained by replacing these acrylic acids with methacrylic acid. Preferred are acrylic acid (2-hydroxyethyl), methacrylic acid (2-hydroxyethyl), acrylic acid (2-hydroxypropyl), and acrylic acid (3-hydroxypropyl).

  Xc is not particularly limited as long as it is an ethylenically unsaturated monomer other than Xa and Xb and copolymerizable, but preferably has no aromatic ring.

  The molar composition ratio of Xa, Xb, and Xc = m: n is preferably in the range of 99: 1 to 65:35, and more preferably in the range of 95: 5 to 75:25. P of Xc is 0-10. Xc may be a plurality of monomer units.

  When the molar composition ratio of Xa is large, compatibility with the cellulose ester is improved, but the film thickness direction retardation (Rt) value is increased. When the molar composition ratio of Xb is large, the compatibility is deteriorated, but the effect of reducing the thickness direction retardation (Rt) is high. Further, if the molar composition ratio of Xb exceeds the above range, haze tends to occur during film formation. It is preferable to optimize these and determine the molar composition ratio of Xa and Xb.

  As for the molecular weight of the polymer X, the weight average molecular weight is from 5,000 to 30,000, and more preferably from 8,000 to 25,000.

  By setting the weight average molecular weight to 5,000 or more, it is preferable because the cellulose ester film has advantages such as less dimensional change under high temperature and high humidity and less curling as a polarizing plate protective film. When the weight average molecular weight is 30000 or less, the compatibility with the cellulose ester is further improved, and bleeding out under high temperature and high humidity, and further haze generation immediately after film formation is suppressed.

  The weight average molecular weight of the polymer X can be adjusted by a known molecular weight adjusting method. Examples of such a molecular weight adjusting method include a method of adding a chain transfer agent such as carbon tetrachloride, lauryl mercaptan, octyl thioglycolate, and the like. The polymerization temperature is usually from room temperature to 130 ° C., preferably from 50 ° C. to 100 ° C., but this temperature or the polymerization reaction time can be adjusted.

  Next, the polymer Y is a polymer having a weight average molecular weight of 500 or more and 3000 or less obtained by polymerizing an ethylenically unsaturated monomer Ya having no aromatic ring.

  Here, when the weight average molecular weight of the polymer Y is 500 or more, the residual monomer of the polymer decreases, which is preferable. Moreover, it is preferable to make the weight average molecular weight of the polymer Y 3000 or less in order to maintain the fall performance of the thickness direction retardation (Rt) value.

  Ya is preferably an acrylic or methacrylic monomer having no aromatic ring.

  The polymer Y is represented by the following general formula (8).

-(Ya) k- (Yb) q- (8)
More preferably, it is a polymer represented by the following general formula (9).

_{^{- [CH 2 -C (-R 5}} ) (- CO 2 R 6)] k- [Yb] q- ... (9)
(Wherein R ⁵ represents H or CH ₃ , R ⁶ represents an alkyl group or a cycloalkyl group having 1 to 12 carbon atoms, Yb represents a monomer unit copolymerizable with Ya, and k and q represents a molar composition ratio, where k ≠ 0 and k + q = 100.
Yb is not particularly limited as long as it is an ethylenically unsaturated monomer copolymerizable with Ya. Yb may be plural. k + q = 100, q is preferably 0-30.

  The ethylenically unsaturated monomer Ya constituting the polymer Y obtained by polymerizing an ethylenically unsaturated monomer having no aromatic ring is, for example, methyl acrylate, ethyl acrylate, propyl acrylate (i- , N-), butyl acrylate (n-, i-, s-, t-), pentyl acrylate (n-, i-, s-), hexyl acrylate (n-, i-), heptyl acrylate (N-, i-), octyl acrylate (n-, i-), nonyl acrylate (n-, i-), myristyl acrylate (n-, i-), cyclohexyl acrylate, acrylic acid (2- Ethyl hexyl), acrylic acid (ε-caprolactone), acrylic acid (2-hydroxyethyl), acrylic acid (2-hydroxypropyl), acrylic acid (3-hydroxypropiyl) ), Acrylic acid (4-hydroxybutyl), acrylic acid (2-hydroxybutyl), methacrylic acid ester, the above acrylic acid ester changed to methacrylic acid ester; unsaturated acid such as acrylic acid, methacrylic acid, Mention may be made of maleic anhydride, crotonic acid, itaconic acid and the like.

  Yb is not particularly limited as long as it is an ethylenically unsaturated monomer copolymerizable with Ya. Examples of vinyl esters include vinyl acetate, vinyl propionate, vinyl butyrate, vinyl valerate, vinyl pivalate, and vinyl caproate. Vinyl caprate, vinyl laurate, vinyl myristate, vinyl palmitate, vinyl stearate, vinyl cyclohexanecarboxylate, vinyl octylate, vinyl methacrylate, vinyl crotonate, vinyl sorbate, vinyl cinnamate and the like are preferred. Yb may be plural.

  In order to synthesize the polymer X and the polymer Y, it is difficult to control the molecular weight in normal polymerization, and it is desirable to use a method that can make the molecular weights as uniform as possible without increasing the molecular weight.

  Polymerization methods of polymer X and polymer Y include a method using a peroxide polymerization initiator such as cumene peroxide and t-butyl hydroperoxide, a method using a polymerization initiator in a larger amount than normal polymerization, and a polymerization start. A method using a chain transfer agent such as a mercapto compound or carbon tetrachloride in addition to the agent, a method using a polymerization terminator such as benzoquinone or dinitrobenzene in addition to the polymerization initiator, and JP 2000-128911 A or Examples thereof include a method of bulk polymerization using a compound having one thiol group and a secondary hydroxyl group described in JP-A-2000-344823, or a polymerization catalyst in which the compound and an organometallic compound are used in combination. .

  The polymer Y is preferably a polymerization method using a compound having a thiol group and a secondary hydroxyl group in the molecule as a chain transfer agent. In this case, the terminal of the polymer Y has a hydroxyl group and a thioether resulting from the polymerization catalyst and the chain transfer agent. By this terminal residue, the compatibility between the polymer Y and the cellulose ester can be adjusted.

  The hydroxyl value of the polymer X and the polymer Y is preferably 30 to 150 [mg KOH / g].

  Here, the measurement of a hydroxyl value is based on JISK0070 (1992). This hydroxyl value is defined as the number of mg of potassium hydroxide required to neutralize acetic acid bonded to a hydroxyl group when 1 g of a sample is acetylated. Specifically, a sample xg (about 1 g) is precisely weighed in a flask, and 20 ml of an acetylating reagent (a solution obtained by adding pyridine to 20 ml of acetic anhydride to 400 ml) is accurately added thereto. An air cooling tube is attached to the mouth of the flask and heated in a glycerin bath at 95-100 ° C. After 1 hour and 30 minutes, the mixture is cooled, 1 ml of purified water is added from an air condenser, and acetic anhydride is decomposed into acetic acid. Next, titration is performed with a 0.5 mol / L potassium hydroxide ethanol solution using a potentiometric titrator, and the inflection point of the obtained titration curve is set as the end point. Further, as a blank test, titration is performed without a sample, and an inflection point of the titration curve is obtained. The hydroxyl value is calculated by the following formula.

Hydroxyl value = {(BC) × f × 28.05 / x} + D
(In the formula, B is the amount of 0.5 mol / L potassium hydroxide ethanol solution (ml) used for the blank test, and C is the amount of 0.5 mol / L potassium hydroxide ethanol solution used for titration ( ml), f is a factor of 0.5 mol / L potassium hydroxide ethanol solution, D is acid value, and 28.05 is 1/2 of 1 mol amount of potassium hydroxide 56.11)
The content of the polymer X and the polymer Y in the cellulose ester film is preferably in the range satisfying the following formulas (i) and (ii). When the content of the polymer X is xg (mass% = the mass of the polymer X / the mass of the cellulose ester × 100) and the content of the polymer Y is yg (mass%),
Formula (i) 5 ≦ xg + yg ≦ 35 (mass%)
Formula (ii) 0.05 ≦ yg / (xg + yg) ≦ 0.4
A preferable range of the formula (i) is 10 to 25% by mass.

  In addition, the weight average molecular weight Mw of a polymer can be measured using gel permeation chromatography.

  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. Thirteen samples are used at approximately equal intervals.

  If the total amount of the polymer X and the polymer Y is 5% by mass or more, the polymer X and the polymer Y sufficiently act to reduce the thickness direction retardation (Rt) value. Moreover, if it is 35 mass% or less as a total amount, adhesiveness with polarizer PVA is favorable.

  The polymer X and the polymer Y can be directly added and dissolved as a material constituting the dope solution described later, or can be added to the dope solution after being previously dissolved in an organic solvent for dissolving the cellulose ester.

  The total content of the plasticizer in the cellulose ester film is preferably 5 to 20% by mass, more preferably 6 to 16% by mass, and particularly preferably 8 to 13% by mass with respect to the total solid content. The contents of the two kinds of plasticizers are each at least 1% by mass, preferably 2% by mass or more.

  The polyhydric alcohol ester plasticizer is preferably contained in an amount of 1 to 15% by mass, particularly preferably 3 to 11% by mass. If the content of the polyhydric alcohol ester plasticizer is small, deterioration of planarity is recognized, and if it is too large, bleeding out is likely to occur. The mass ratio of the polyhydric alcohol ester plasticizer and the other plasticizer is preferably in the range of 1: 4 to 4: 1, and more preferably 1: 3 to 3: 1. If the amount of the plasticizer added is too large or too small, the film is liable to be deformed and is not preferable.

(Solution casting film forming method)
The cellulose ester film is produced by a solution casting method, in which a cellulose ester and an additive are dissolved in a solvent to prepare a dope, a dope is cast on a belt-shaped or drum-shaped metal support, It is performed by a step of drying the stretched dope as a web, a step of peeling from the metal support, a step of stretching or maintaining the width, a step of further drying, and a step of winding the finished film.

  First, the process for preparing the dope will be described. The concentration of cellulose ester in the dope is preferably higher because the drying load after casting on the metal support can be reduced. However, if the concentration of cellulose ester is too high, the load during filtration increases and the filtration accuracy increases. Becomes worse. The concentration for achieving both of these is preferably 10 to 35% by mass, and more preferably 15 to 25% by mass.

  The solvent used in the dope may be used alone or in combination of two or more, but it is preferable to use a mixture of a good solvent and a poor solvent of cellulose ester in terms of production efficiency, and there are many good solvents. This is preferable from the viewpoint of the solubility of the cellulose ester. The preferable range of the mixing ratio of the good solvent and the poor solvent is 70 to 98% by mass for the good solvent and 2 to 30% by mass for the poor solvent. With a good solvent and a poor solvent, what dissolve | melts the cellulose ester to be used independently is defined as a good solvent, and what poorly swells or does not melt | dissolve is defined as a poor solvent. Therefore, depending on the acyl group substitution degree of the cellulose ester, the good solvent and the poor solvent change. For example, when acetone is used as the solvent, the cellulose ester acetate ester (acetyl group substitution degree 2.4) and cellulose acetate propionate are good. As a solvent, cellulose acetate (acetyl group substitution degree 2.8) is a poor solvent.

  The good solvent used in the present invention is not particularly limited, and examples thereof include organic halogen compounds such as methylene chloride, dioxolanes, acetone, methyl acetate, and methyl acetoacetate. Particularly preferred is methylene chloride or methyl acetate.

  Moreover, the poor solvent used in the present invention is not particularly limited, but for example, methanol, ethanol, n-butanol, cyclohexane, cyclohexanone, and the like are preferably used. Moreover, it is preferable that 0.01-2 mass% of water contains in dope.

  A general method can be used as a dissolution method of the cellulose ester when preparing the dope described above. When heating and pressurization are combined, it is possible to heat above the boiling point at normal pressure. It is preferable to stir and dissolve while heating at a temperature that is equal to or higher than the boiling point of the solvent at normal pressure and that the solvent does not boil under pressure, in order to prevent the generation of massive undissolved materials called gels and mamacos. Moreover, after mixing a cellulose ester with a poor solvent and making it wet or swell, the method of adding a good solvent and melt | dissolving is also used preferably.

  Pressurization may be performed by a method of injecting an inert gas such as nitrogen gas or a method of increasing the vapor pressure of the solvent by heating. Heating is preferably performed from the outside. For example, a jacket type is preferable because temperature control is easy.

  The heating temperature with the addition of the solvent is preferably higher from the viewpoint of the solubility of the cellulose ester, but if the heating temperature is too high, the required pressure increases and the productivity deteriorates. A preferable heating temperature is 45 to 120 ° C, more preferably 60 to 110 ° C, and still more preferably 70 ° C to 105 ° C. The pressure is adjusted so that the solvent does not boil at the set temperature.

  Alternatively, a cooling dissolution method is also preferably used, whereby the cellulose ester can be dissolved in a solvent such as methyl acetate.

  Next, this cellulose ester solution is filtered using a suitable filter medium such as filter paper. As the filter medium, in order to remove insoluble matters and the like, it is preferable that the absolute filtration accuracy is small. However, if the absolute filtration accuracy is too small, there is a problem that the filter medium is likely to be clogged. For this reason, a filter medium with an absolute filtration accuracy of 0.008 mm or less is preferable, a filter medium with 0.001 to 0.008 mm is more preferable, and a filter medium with 0.003 to 0.006 mm is more preferable.

  The material of the filter medium is not particularly limited, and a normal filter medium can be used. However, a plastic filter medium such as polypropylene or Teflon (registered trademark), or a metal filter medium such as stainless steel may cause fibers to fall off. Less preferred. It is preferable to remove and reduce impurities, particularly bright spot foreign matter, contained in the raw material cellulose ester by filtration.

In this specification, the bright spot foreign material is arranged in a crossed Nicol state with two polarizing plates, a cellulose ester film is placed between them, light is applied from one polarizing plate side, It is a point (foreign matter) that light from the opposite side appears to leak when observed from the side, and the number of bright spots having a diameter of 0.01 mm or more is preferably 200 pieces / cm ² or less. More preferably, it is 100 pieces / cm < ² > or less, More preferably, it is 50 pieces / m < ² > or less, More preferably, it is 0-10 pieces / cm < ² > or less. Further, it is preferable that the number of bright spots of 0.01 mm or less is small.

  The dope can be filtered by a normal method, but the method of filtering while heating at a temperature not lower than the boiling point of the solvent at normal pressure and in a range where the solvent does not boil under pressure is the filtration pressure before and after filtration. The increase in the difference (referred to as differential pressure) is small and preferable. A preferred temperature is 45 to 120 ° C, more preferably 45 to 70 ° C, and even more preferably 45 to 55 ° C.

  A smaller filtration pressure is preferred. The filtration pressure is preferably 1.6 MPa or less, more preferably 1.2 MPa or less, and further preferably 1.0 MPa or less.

  Next, dope casting will be described.

  The metal support in the casting (casting) step preferably has a mirror-finished surface. As the metal support, a stainless steel belt or a drum whose surface is plated with a casting is preferably used.

  The cast width can be 1 to 4 m. The surface temperature of the metal support in the casting step is set to −50 ° C. to a temperature at which the solvent boils and does not foam. Higher temperatures are preferable because the web can be dried faster, but if the temperature is too high, the web may foam or flatness may deteriorate. A preferable support temperature is appropriately determined at 0 to 100 ° C, and more preferably 5 to 30 ° C. Alternatively, it is also a preferable method that the web is gelled by cooling and peeled from the drum in a state containing a large amount of residual solvent.

  The method for controlling the temperature of the metal support is not particularly limited, and there are a method of blowing hot air or cold air, and a method of contacting hot water with the back side of the metal support. It is preferable to use hot water because heat transfer is performed efficiently, so that the time until the temperature of the metal support becomes constant is short. When using warm air, considering the temperature drop of the web due to the latent heat of vaporization of the solvent, while using warm air above the boiling point of the solvent and preventing foaming, there are cases where wind at a temperature higher than the target temperature is used. is there. In particular, it is preferable to perform drying efficiently by changing the temperature of the support and the temperature of the drying air during the period from casting to peeling.

  In order for the cellulose ester film to exhibit good flatness, the residual solvent amount when peeling the web from the metal support is preferably 10 to 150% by mass, more preferably 20 to 40% by mass or 60 to 130% by mass. Especially preferably, it is 20-30 mass% or 70-120 mass%.

  In the present invention, the amount of residual solvent is defined by the following formula.

Residual solvent amount (% by mass) = {(MN) / N} × 100
Here, M is the mass of a sample taken at any time during or after the production of the web or film, and N is the mass after heating M at 115 ° C. for 1 hour.

  Further, in the drying step of the cellulose ester film, the web is peeled off from the metal support, and further dried, and the residual solvent amount is preferably 1% by mass or less, more preferably 0.1% by mass or less, Especially preferably, it is 0-0.01 mass% or less.

  In the film drying process, generally, a roll drying method (a method in which a plurality of rolls arranged on the upper and lower sides are alternately passed through and dried) or a tenter method is used while drying the web.

  In order to produce the cellulose ester film for the antireflection film of the present invention, the web is stretched in the conveying direction where the residual solvent amount of the web immediately after peeling from the metal support is large, and both ends of the web are gripped with clips or the like. It is particularly preferable to perform stretching in the width direction by a tenter method. A preferable draw ratio in both the machine direction and the transverse direction is 1.01 to 1.3 times, and more preferably 1.05 to 1.15 times. It is preferable that the area is 1.12 to 1.44 times, and preferably 1.15 to 1.32 times due to longitudinal and lateral stretching. This can be determined by the draw ratio in the longitudinal direction × the draw ratio in the transverse direction. If one of the stretching ratios in the machine direction and the transverse direction is less than 1.01, the flatness is likely to deteriorate due to ultraviolet irradiation when the hard coat layer is formed.

  In order to stretch in the machine direction immediately after peeling, it is preferable to stretch by peeling tension and subsequent transport tension. For example, it is preferable to peel at a peeling tension of 210 N / m or more, and particularly preferably 220 to 300 N / m.

  The means for drying the web is not particularly limited, and can be generally performed with hot air, infrared rays, a heating roll, microwave, or the like, but it is preferably performed with hot air in terms of simplicity.

    The drying temperature in the web drying step is preferably increased stepwise from 30 to 200 ° C, and more preferably stepwise increased from 50 to 180 ° C in order to improve dimensional stability.

  Although the film thickness of a cellulose-ester film is not specifically limited, 10-200 micrometers is used preferably. In particular, it was difficult to obtain an antireflection film excellent in flatness and scratch resistance with a thin film of 10 to 70 μm. According to the present invention, a thin antireflection film excellent in flatness and scratch resistance was obtained. And the film thickness of the cellulose ester film is particularly preferably 10 to 70 μm. More preferably, it is 20-60 micrometers. Most preferably, it is 35-60 micrometers. Moreover, the cellulose ester film made into the multilayer structure by the co-casting method can also be used preferably. Even when the cellulose ester has a multilayer structure, it has a layer containing an ultraviolet absorber and a plasticizer, and it may be a core layer, a skin layer, or both.

  The antireflection film of the present invention has a width of 1 m or more and preferably has a width of 1.4 to 4 m. Especially preferably, it is 1.4-3 m. If it exceeds 4 m, conveyance becomes difficult. Moreover, the centerline average roughness (Ra) of the surface which provides the antireflection layer of a cellulose-ester film can use a 0.001-1 micrometer thing.

(Melt casting method)
The cellulose ester film is also preferably formed by a melt casting film forming method.

  The molding method by melt casting that is heated and melted without using the solvent (for example, methylene chloride, etc.) used in the solution casting film forming method, more specifically, melt extrusion molding method, press molding method, inflation method, injection It can be classified into molding method, blow molding method, stretch molding method and the like. Among these, in order to obtain a cellulose ester film excellent in mechanical strength, surface accuracy and the like, the melt extrusion method is excellent.

  A mixture of cellulose ester and additives is dried with hot air or vacuum, then melt extruded, extruded into a film from a T-die, and brought into close contact with a cooling drum by an electrostatic application method, etc., and cooled and solidified to obtain an unstretched film . The temperature of the cooling drum is preferably maintained at 90 to 150 ° C.

  The cellulose ester and other additives such as a stabilizer added as necessary are preferably mixed before melting, and more preferably mixed before heating. Mixing may be performed by a mixer or the like, or may be performed in the cellulose ester preparation process. When a mixer is used, a general mixer such as a V-type mixer, a conical screw type mixer, a horizontal cylindrical type mixer, a Henschel mixer, a ribbon mixer, or the like can be used.

  After the film constituent materials are mixed as described above, the mixture may be directly melted and formed into a film using an extruder, but once the film constituent materials are pelletized, the pellets are extruded. The film may be melted to form a film. In addition, when the film constituent material includes a plurality of materials having different melting points, a so-called braided semi-melt is once produced at a temperature at which only a material having a low melting point is melted, and the semi-melt is put into an extruder. It is also possible to form a film. If the film component contains a material that is easily pyrolyzed, in order to reduce the number of times of melting, a method of directly forming a film without producing pellets, or after making a paste-like semi-molten material as described above A method of forming a film is preferred.

  As the extruder, various commercially available extruders can be used, but a melt-kneading extruder is preferable, and a single-screw extruder or a twin-screw extruder may be used. When forming a film directly without producing pellets from film constituent materials, it is preferable to use a twin-screw extruder because an appropriate degree of kneading is required. However, even with a single-screw extruder, the screw shape is a Maddock type. By changing to a kneading type screw such as unimelt or dull mage, moderate kneading can be obtained, so that it can be used. When a pellet or braided semi-melt is once used as a film constituent material, it can be used in either a single screw extruder or a twin screw extruder.

  In the extruder and in the cooling step after extrusion, it is preferable to reduce the oxygen concentration by replacing with an inert gas such as nitrogen gas or reducing the pressure.

  The melting temperature of the film constituent material in the extruder varies depending on the viscosity and discharge amount of the film constituent material, the thickness of the sheet to be manufactured, etc., but generally, with respect to the glass transition temperature (Tg) of the film, Tg or more and Tg + 100 ° C. or less, preferably Tg + 10 ° C. or more and Tg + 90 ° C. or less. Specifically, the temperature during melt extrusion is preferably 150 to 300 ° C, and particularly preferably 180 to 270 ° C. Furthermore, it is preferable that it is the range of 200-250 degreeC.

  The melt viscosity at the time of extrusion is 10 to 100,000 poise, preferably 100 to 10,000 poise.

  Further, the residence time of the film constituting material in the extruder is preferably shorter, and is within 5 minutes, preferably within 3 minutes, more preferably within 2 minutes. Although the residence time depends on the type of the extruder 1 and the extrusion conditions, it can be shortened by adjusting the material supply amount, L / D, screw rotation speed, screw groove depth, etc. It is.

  Extruded into a film by the above extruder, brought into close contact with a cooling drum by an electrostatic application method or the like, cooled and solidified to obtain an unstretched film. The temperature of the cooling drum is preferably maintained at 90 to 150 ° C.

  The cellulose ester film used in the present invention is particularly preferably a film stretched in the width direction or the film forming direction.

  The unstretched film peeled off from the cooling drum is heated within a range of Tg + 100 ° C. from the glass transition temperature (Tg) of the cellulose ester via a plurality of roll groups and / or a heating device such as an infrared heater. In addition, it is preferable to perform single-stage or multistage longitudinal stretching.

  Next, the cellulose ester film stretched in the longitudinal direction obtained as described above is preferably stretched in the transverse direction and then heat-treated.

  The heat treatment is preferably carried out while being conveyed for 0.5 to 300 seconds in the range of glass transition temperature (Tg) −20 ° C. to stretching temperature.

  The heat-treated film is usually cooled to a glass transition temperature (Tg) or lower, and clip holding portions at both ends of the film are cut and wound. Further, the cooling is preferably performed by gradually cooling from the final heat treatment temperature to the glass transition temperature (Tg) at a cooling rate of 100 ° C. or less per second.

  The means for cooling is not particularly limited, and can be performed by a conventionally known means. However, it is preferable to perform these treatments while sequentially cooling in a plurality of temperature ranges in view 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 treatment temperature and t is the time until the film reaches Tg from the final heat treatment temperature.

  An ultraviolet absorber is preferably used for the cellulose ester film.

  As the ultraviolet absorber, those excellent in the ability to absorb ultraviolet rays having a wavelength of 370 nm or less and having a small absorption of visible light having a wavelength of 400 nm or more are preferably used from the viewpoint of good liquid crystal display properties.

  Specific examples of the ultraviolet absorber include, for example, oxybenzophenone compounds, benzotriazole compounds, salicylic acid ester compounds, benzophenone compounds, cyanoacrylate compounds, triazine compounds, nickel complex compounds, and the like. It is not limited to.

  Specific examples of the benzotriazole-based ultraviolet absorbers include the following ultraviolet absorbers, but the present invention is not limited thereto.

UV-1: 2- (2'-hydroxy-5'-methylphenyl) benzotriazole UV-2: 2- (2'-hydroxy-3 ', 5'-di-tert-butylphenyl) benzotriazole UV-3 : 2- (2'-hydroxy-3'-tert-butyl-5'-methylphenyl) benzotriazole UV-4: 2- (2'-hydroxy-3 ', 5'-di-tert-butylphenyl)- 5-Chlorobenzotriazole UV-5: 2- (2'-hydroxy-3 '-(3 ", 4", 5 ", 6" -tetrahydrophthalimidomethyl) -5'-methylphenyl) benzotriazole UV-6: 2,2-methylenebis (4- (1,1,3,3-tetramethylbutyl) -6- (2H-benzotriazol-2-yl) phenol)
UV-7: 2- (2'-hydroxy-3'-tert-butyl-5'-methylphenyl) -5-chlorobenzotriazole UV-8: 2- (2H-benzotriazol-2-yl) -6 (Linear and side chain dodecyl) -4-methylphenol (TINUVIN171, manufactured by Ciba)
UV-9: Octyl-3- [3-tert-butyl-4-hydroxy-5- (chloro-2H-benzotriazol-2-yl) phenyl] propionate and 2-ethylhexyl-3- [3-tert-butyl- Mixture of 4-hydroxy-5- (5-chloro-2H-benzotriazol-2-yl) phenyl] propionate (TINUVIN 109, manufactured by Ciba)
Moreover, although the following specific example is shown as a benzophenone series ultraviolet absorber, this invention is not limited to these.

UV-10: 2,4-dihydroxybenzophenone UV-11: 2,2'-dihydroxy-4-methoxybenzophenone UV-12: 2-hydroxy-4-methoxy-5-sulfobenzophenone UV-13: Bis (2-methoxy -4-hydroxy-5-benzoylphenylmethane)
As the UV absorber preferably used, a benzotriazole UV absorber and a benzophenone UV absorber that are highly transparent and excellent in preventing the deterioration of the polarizing plate and the liquid crystal are preferable, and the benzotriazole type with less unnecessary coloring. A UV absorber is particularly preferably used. As commercial products, TINUVIN 326, TINUVIN 109, TINUVIN 171, TINUVIN 900, TINUVIN 928, TINUVIN 928, TINUVIN 360 (all manufactured by Ciba Specialty Chemicals) LA31 (manufactured by Asahi Denka), Sumisorb 250 (manufactured by Sumitomo Chemical), and RUVA-100 (manufactured by Otsuka Chemical).

  Moreover, the ultraviolet absorber whose distribution coefficient described in Unexamined-Japanese-Patent No. 2001-187825 is 9.2 or more improves the surface quality of a long film, and is excellent also in applicability | paintability. In particular, it is preferable to use an ultraviolet absorber having a distribution coefficient of 10.1 or more.

  Moreover, in order to provide slipperiness to a cellulose-ester film, the particle | grains similar to what is described in the application layer containing the above-mentioned active ray curable resin can be used.

  As particles, examples of inorganic compounds include silicon dioxide, titanium dioxide, aluminum oxide, zirconium oxide, calcium carbonate, calcium carbonate, talc, clay, calcined kaolin, calcined calcium silicate, hydrated calcium silicate, aluminum silicate And magnesium silicate and calcium phosphate. Particles containing silicon are preferred from the viewpoint of low turbidity, and silicon dioxide is particularly preferred.

  The average primary particle diameter of the particles is preferably 5 to 50 nm, and more preferably 7 to 20 nm. These are preferably contained mainly as secondary aggregates having a particle size of 0.05 to 0.3 μm. The content is preferably 0.05 to 1% by mass, particularly preferably 0.1 to 0.5% by mass.

  Silicon dioxide particles are commercially available under the trade names of, for example, Aerosil R972, R972V, R974, R812, 200, 200V, 300, R202, OX50, TT600 (manufactured by Nippon Aerosil Co., Ltd.), and these particles are used. can do.

  Zirconium oxide particles are commercially available, for example, under the trade names Aerosil R976 and R811 (manufactured by Nippon Aerosil Co., Ltd.), and can be used.

  Polymer particles can also be used as the particles, and examples of the polymer include silicone resins, fluororesins, and acrylic resins. 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.) Are commercially available and can be used.

  Among these, Aerosil 200V and Aerosil R972V are particularly preferably used because they have a large effect of reducing the friction coefficient while keeping turbidity low.

  Moreover, it is preferable to contain the deterioration inhibitor demonstrated below in a cellulose-ester film. Next, the deterioration preventing agent will be described.

(Deterioration inhibitor)
The deterioration preventing agent is a material that suppresses decomposition of a polymer by heat, oxygen, moisture, acid, or the like by a chemical action. In the case of the melt casting method, the transparent substrate film used in the present invention is formed at a high temperature of 200 ° C. or more. It is preferable to make it contain in material.

  It is represented by coloring and molecular weight reduction, including decomposition reactions that have not been elucidated, such as preventing oxidation of film-forming materials, capturing acid generated by decomposition, and suppressing or prohibiting decomposition reactions caused by radical species due to light or heat. Degradation inhibitors are used to suppress the generation of volatile components due to deterioration and material decomposition.

  Examples of the degradation inhibitor include, but are not limited to, an antioxidant, a hindered amine light stabilizer, an acid scavenger, and a metal deactivator. These are described in JP-A-3-199201, JP-A-5-1907073, JP-A-5-194789, JP-A-5-271471, JP-A-6-107854, and the like. Among these, it is preferable that an antioxidant is included as a deterioration preventing agent in the film forming material.

  At least one or more kinds of deterioration preventing agents in the film forming material can be selected, and the amount added from the transparency of the film is the addition of the deterioration preventing agent with respect to 100% by mass of the transparent substrate resin forming the transparent substrate film. The amount is preferably 0.01% by mass or more and 10% by mass or less, more preferably 0.1% by mass or more and 5.0% by mass or less, and further preferably 0.2% by mass or more and 2.0% by mass. It is as follows.

  The film-forming material can be stored by dividing the constituent material into one or a plurality of types of pellets for the purpose of avoiding material alteration and hygroscopicity. Pelletization may improve the mixing or compatibility of the melt during heating, or may ensure the optical uniformity of the resulting film.

(Antioxidant)
Moreover, it is preferable to contain the antioxidant demonstrated below in a cellulose-ester film. Any antioxidant can be used without limitation as long as it is a compound that suppresses the deterioration of the film-forming material due to oxygen. Among them, a phenol-based antioxidant, a phosphorus-based antioxidant, a sulfur-based antioxidant, an alkyl radical scavenger, and the like. Agents, peroxide decomposers, oxygen scavengers and the like. Among these, phenolic antioxidants, phosphorus antioxidants, and alkyl radical scavengers are preferable, but it is more preferable to use a combination of two of a phenolic antioxidant and a phosphorus antioxidant, and phenolic antioxidants. It is most preferable to use a combination of three of an agent, a phosphorus-based antioxidant, and an alkyl radical scavenger. By blending these antioxidants, it is possible to prevent coloration or strength reduction of the molded product due to heat during heat molding or deterioration due to thermal oxidation without lowering transparency, heat resistance and the like. These antioxidants can be used singly 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 the cellulose ester used in the present invention. Is preferably 0.01% by mass or more and 10% by mass or less, more preferably 0.1% by mass or more and 5.0% by mass or less, and still more preferably 0.2% by mass or more and 2.0% by mass. % Or less.

(Phenolic antioxidant)
Phenol-based antioxidants are known compounds. In addition to alkyl group-substituted phenols such as para-t-butylphenol and para- (1,1,3,3-tetramethylbutyl) phenol, for example, US Pat. Examples include 2,6-dialkylphenol derivative compounds, so-called hindered phenol compounds, described in columns 12 to 14 of the specification of 839,405. Among these, hindered phenol compounds are preferable.

  Specific examples of the hindered phenol 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-t-butyl-4-hydroxyphenylbenzoate, neo-dodecyl 3- (3,5-di-t-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-phenyl acetate, 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 bis- (3,5-di -T-butyl-4-hydroxy-phenyl) propionate, 2- (n-octadecylthio) ethyl 3- (3,5-di-t-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-t-butyl-4-hydroxyphenyl) ) Propionate], 2- (2-stearoyloxyethylthio) ethyl 3,5-di-t-butyl-4-hydroxybenzoate, 2- (2-stearoyloxyethylthio) ethyl 7- (3-methyl-5- t-butyl-4-hydroxyphenyl) heptanoate, 1,2-propylene glycol bis- [3- (3,5-di-t-butyl- -Hydroxyphenyl) propionate], ethylene glycol bis- [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], neopentylglycol bis- [3- (3,5-di-t- Butyl-4-hydroxyphenyl) propionate], ethylene glycol bis- (3,5-di-t-butyl-4-hydroxyphenyl acetate), glycerin-1-n-octadecanoate-2,3-bis- ( 3,5-di-t-butyl-4-hydroxyphenyl acetate), pentaerythritol-tetrakis- [3- (3 ', 5'-di-t-butyl-4'-hydroxyphenyl) propionate], 1,1 , 1-Trimethylolethane-tris- [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propione ), Sorbitol hexa- [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], 2-hydroxyethyl 7- (3-methyl-5-tbutyl-4-hydroxyphenyl) propionate 2-stearoyloxyethyl 7- (3-methyl-5-t-butyl-4-hydroxyphenyl) heptanoate, 1,6-n-hexanediol-bis [(3 ', 5'-di-t-butyl- 4-hydroxyphenyl) propionate], pentaerythritol-tetrakis (3,5-di-t-butyl-4-hydroxyhydrocinnamate). The above type of phenolic compounds are commercially available from Ciba Specialty Chemicals under the trade names “IRGANOX1076” and “IRGANOX1010”, for example.

(Phosphorus antioxidant)
Examples of phosphorus antioxidants include phosphite compounds and phosphonite compounds. Specific examples of the phosphite compound include triphenyl phosphite, diphenylisodecyl phosphite, phenyl diisodecyl phosphite, tris (nonylphenyl) phosphite, tris (dinonylphenyl) phosphite, tris (2,4-di -T-butylphenyl) phosphite, tris (2,4-di-t-butyl-5-methylphenyl) phosphite, 10- (3,5-di-t-butyl-4-hydroxybenzyl) -9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, 6- [3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propoxy] -2,4,8,10- Mono such as tetra-t-butyldibenz [d, f] [1.3.2] dioxaphosphine, tridecyl phosphite Sphite compounds; 4,4'-butylidene-bis (3-methyl-6-tert-butylphenyl-di-tridecyl phosphite), 4,4'-isopropylidene-bis (phenyl-di-alkyl (C12- And diphosphite compounds such as C15) phosphite). The above type of phosphite compounds are, for example, Sumitomo Chemical Co., Ltd., “Sumilizer GP”, Asahi Denka Kogyo Co., Ltd. “ADK STAB PEP-24G”, “ADK STAB PEP-36”, “ADK STAB 3010”, “ It is marketed under the brand names of “ADK STAB HP-10” and “ADK STAB 2112”.

  Specific examples of the phosphonite compound include dimethyl-phenylphosphonite, di-t-butyl-phenylphosphonite, diphenyl-phenylphosphonite, di- (4-pentyl-phenyl) -phenylphosphonite, di- (2- t-butyl-phenyl) -phenylphosphonite, di- (2-methyl-3-pentyl-phenyl) -phenylphosphonite, di- (2-methyl-4-octyl-phenyl) -phenylphosphonite, di- ( 3-butyl-4-methyl-phenyl) -phenylphosphonite, di- (3-hexyl-4-ethyl-phenyl) -phenylphosphonite, di- (2,4,6-trimethylphenyl) -phenylphosphonite, Di- (2,3-dimethyl-4-ethyl-phenyl) -phenylphosphonite, di- (2,6-diethi -3-butylphenyl) -phenylphosphonite, di- (2,3-dipropyl-5-butylphenyl) -phenylphosphonite, di- (2,4,6-tri-t-butylphenyl) -phenylphosphonite Bis (2,4-di-t-butyl-5-methylphenyl) biphenyl-4-yl-phosphonite, bis (2,4-di-t-butyl-5-methylphenyl) -4 '-(bis ( 2,4-di-tert-butyl-5-methylphenoxy) phosphino) biphenyl-4-yl-phosphonite, tetrakis (2,4-di-tert-butyl-phenyl) -4,4'-biphenylenediphosphonite, Tetrakis (2,5-di-t-butyl-phenyl) -4,4'-biphenylenediphosphonite, tetrakis (3,5-di-t-butyl-phenyl) -4,4'-bif Nylene diphosphonite, tetrakis (2,3,4-trimethylphenyl) -4,4'-biphenylene diphosphonite, tetrakis (2,3-dimethyl-5-ethyl-phenyl) -4,4'-biphenylene diphospho Knight, tetrakis (2,3-dimethyl-4-propylphenyl) -4,4'-biphenylene diphosphonite, tetrakis (2,3-dimethyl-5-t-butylphenyl) -4,4'-biphenylene diphospho Knight, tetrakis (2,5-dimethyl-4-t-butylphenyl) -4,4'-biphenylene diphosphonite, tetrakis (2,3-diethyl-5-methylphenyl) -4,4'-biphenylene diphospho Knight, tetrakis (2,6-diethyl-4-methylphenyl) -4,4'-biphenylenediphosphonite, tetrakis (2,4,5-triethylphenyl) -4,4'-biphenylenediphosphonite, tetrakis (2,6-diethyl-4-propylphenyl) -4,4'-biphenylenediphosphonite, tetrakis (2, 5-diethyl-6-butylphenyl) -4,4'-biphenylenediphosphonite, tetrakis (2,3-diethyl-5-t-butylphenyl) -4,4'-biphenylenediphosphonite, tetrakis (2, 5-diethyl-6-tert-butylphenyl) -4,4'-biphenylenediphosphonite, tetrakis (2,3-dipropyl-5-methylphenyl) -4,4'-biphenylenediphosphonite, tetrakis (2, 6-dipropyl-4-methylphenyl) -4,4'-biphenylenediphosphonite, tetrakis (2,6-dipropyl-5- Tilphenyl) -4,4'-biphenylenediphosphonite, tetrakis (2,3-dipropyl-6-butylphenyl) -4,4'-biphenylenediphosphonite, tetrakis (2,6-dipropyl-5-butylphenyl) -4,4'-biphenylenediphosphonite, tetrakis (2,3-dibutyl-4-methylphenyl) -4,4'-biphenylenediphosphonite, tetrakis (2,5-dibutyl-3-methylphenyl) -4 , 4'-biphenylenediphosphonite, tetrakis (2,6-dibutyl-4-methylphenyl) -4,4'-biphenylenediphosphonite, tetrakis (2,4-di-t-butyl-3-methylphenyl) -4,4'-biphenylenediphosphonite, tetrakis (2,4-di-t-butyl-5-methylphenyl) -4 4'-biphenylenediphosphonite, tetrakis (2,4-di-t-butyl-6-methylphenyl) -4,4'-biphenylenediphosphonite, tetrakis (2,5-di-t-butyl-3- Methylphenyl) -4,4'-biphenylenediphosphonite, tetrakis (2,5-di-t-butyl-4-methylphenyl) -4,4'-biphenylenediphosphonite, tetrakis (2,5-di-) t-butyl-6-methylphenyl) -4,4'-biphenylenediphosphonite, tetrakis (2,6-di-t-butyl-3-methylphenyl) -4,4'-biphenylenediphosphonite, tetrakis ( 2,6-di-t-butyl-4-methylphenyl) -4,4'-biphenylenediphosphonite, tetrakis (2,6-di-t-butyl-5-methylphenyl) -4,4'-biphenylenediphosphonite, tetrakis (2,3-dibutyl-4-ethylphenyl) -4,4'-biphenylenediphosphonite, tetrakis (2,4-dibutyl-3-ethylphenyl) -4 , 4'-biphenylenediphosphonite, tetrakis (2,5-dibutyl-4-ethylphenyl) -4,4'-biphenylenediphosphonite, tetrakis (2,4-di-t-butyl-3-ethylphenyl) -4,4'-biphenylenediphosphonite, tetrakis (2,4-di-t-butyl-5-ethylphenyl) -4,4'-biphenylenediphosphonite, tetrakis (2,4-di-t-butyl) -6-ethylphenyl) -4,4'-biphenylenediphosphonite, tetrakis (2,5-di-t-butyl-3-ethylphenyl) -4,4'- Phenylenediphosphonite, tetrakis (2,5-di-t-butyl-4-ethylphenyl) -4,4'-biphenylenediphosphonite, tetrakis (2,5-di-t-butyl-6-ethylphenyl) -4,4'-biphenylenediphosphonite, tetrakis (2,6-di-t-butyl-3-ethylphenyl) -4,4'-biphenylenediphosphonite, tetrakis (2,6-di-t-butyl) -4-ethylphenyl) -4,4'-biphenylenediphosphonite, tetrakis (2,6-di-t-butyl-5-ethylphenyl) -4,4'-biphenylenediphosphonite, tetrakis (2,3 , 4-tributylphenyl) -4,4'-biphenylenediphosphonite, tetrakis (2,4,6-tri-t-butylphenyl) -4,4'-biphenylene Phosphonite, and the like. The phosphorus compound of the above type is commercially available, for example, from Ciba Specialty Chemicals Co., Ltd. under the trade name “IRGAFOSP-EPQ” and from Sakai Chemical Industry Co., Ltd. as “GSY-P101”.

  As the phosphorus antioxidant, phosphonite compounds are preferable, and among them, 4,4'-biphenylene diphosphonite such as tetrakis (2,4-di-t-butyl-phenyl) -4,4'-biphenylene diphosphonite. Compounds are preferred and tetrakis (2,4-di-t-butyl-5-methylphenyl) -4,4'-biphenylenediphosphonite is particularly preferred.

(Alkyl radical scavenger)
The cellulose ester film preferably contains an alkyl radical scavenger described below. The term “alkyl radical scavenger” as used herein means a compound that has a group with which an alkyl radical can react rapidly and gives a stable product in which no subsequent reaction occurs after the reaction with the alkyl radical.

  Alkyl radical scavengers are commercially available from Sumitomo Chemical Co., Ltd. under the trade names “Sumilizer GM” and “Sumilizer GS”.

(Hindered amine light stabilizer)
Cellulose ester films have hindered amine light stabilizers (degradation inhibitors for film-forming materials during heat melting, and as degradation inhibitors for external light exposed as a polarizer protective film after production and light from the backlight of liquid crystal displays) It is preferred to add a HALS) compound. Examples of the hindered amine light stabilizer are described in US Pat. No. 4,619,956, columns 5-11 and US Pat. No. 4,839,405, columns 3-5. 2,2,6,6-tetraalkylpiperidine compounds, or acid addition salts thereof or complexes of these with metal compounds.

  Specific examples of the hindered amine light stabilizer include bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis (2,2,6,6-tetramethyl-4-piperidyl) succinate, bis ( 1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, bis (N-octoxy-2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis (N-benzyloxy-2, 2,6,6-tetramethyl-4-piperidyl) sebacate, bis (N-cyclohexyloxy-2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis (1,2,2,6,6) -Pentamethyl-4-piperidyl) 2- (3,5-di-t-butyl-4-hydroxybenzyl) -2-butylmalonate, bis (1-acryloyl-2,2,6,6- Tramethyl-4-piperidyl) 2,2-bis (3,5-di-tert-butyl-4-hydroxybenzyl) -2-butylmalonate, bis (1,2,2,6,6-pentamethyl-4- Piperidyl) decanedioate, 2,2,6,6-tetramethyl-4-piperidyl methacrylate, 4- [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionyloxy] -1- [ 2- (3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionyloxy) ethyl] -2,2,6,6-tetramethylpiperidine, 2-methyl-2- (2,2, 6,6-tetramethyl-4-piperidyl) amino-N- (2,2,6,6-tetramethyl-4-piperidyl) propionamide, tetrakis (2,2,6,6-tetramethyl-4-piperidyl) 1,2,3,4-butane tetracarboxylate, tetrakis (1,2,2,6,6-pentamethyl-4-piperidyl) 1,2,3,4-butane tetracarboxylate, and the like.

  Further, it may be a polymer type compound. As specific examples, N, N ′, N ″, N ″ ′-tetrakis- [4,6-bis- [butyl- (N-methyl-2,2,6, 6-tetramethylpiperidin-4-yl) amino] -triazin-2-yl] -4,7-diazadecane-1,10-diamine, dibutylamine and 1,3,5-triazine-N, N′-bis ( 2,2,6,6-tetramethyl-4-piperidyl) -1,6-hexamethylenediamine and N- (2,2,6,6-tetramethyl-4-piperidyl) butylamine polycondensate, di Polycondensate of butylamine, 1,3,5-triazine and N, N′-bis (2,2,6,6-tetramethyl-4-piperidyl) butylamine, poly [{(1,1,3,3 -Tetramethylbutyl) amino-1,3,5-tri Gin-2,4-diyl} {(2,2,6,6-tetramethyl-4-piperidyl) imino} hexamethylene {(2,2,6,6-tetramethyl-4-piperidyl) imino}], Weight of 1,6-hexanediamine-N, N'-bis (2,2,6,6-tetramethyl-4-piperidyl) and morpholine-2,4,6-trichloro-1,3,5-triazine Condensate, poly [(6-morpholino-s-triazine-2,4-diyl) [(2,2,6,6-tetramethyl-4-piperidyl) imino] -hexamethylene [(2,2,6, 6-tetramethyl-4-piperidyl) imino]] and other high molecular weight HALS in which a plurality of piperidine rings are bonded via a triazine skeleton; dimethyl succinate and 4-hydroxy-2,2,6,6-tetramethyl-1 -Piperidine Etano 1,2,3,4-butanetetracarboxylic acid, 1,2,2,6,6-pentamethyl-4-piperidinol and 3,9-bis (2-hydroxy-1,1-dimethyl) (Ethyl) -2,4,8,10-tetraoxaspiro [5,5] undecane and the like, and the like are exemplified by compounds in which a piperidine ring is bonded through an ester bond, but the present invention is not limited thereto. It is not a thing.

  Among these, polycondensates of dibutylamine, 1,3,5-triazine and N, N′-bis (2,2,6,6-tetramethyl-4-piperidyl) butylamine, poly [{(1, 1,3,3-tetramethylbutyl) amino-1,3,5-triazine-2,4-diyl} {(2,2,6,6-tetramethyl-4-piperidyl) imino} hexamethylene {(2 , 2,6,6-tetramethyl-4-piperidyl) imino}], a polymer of dimethyl succinate and 4-hydroxy-2,2,6,6-tetramethyl-1-piperidineethanol, etc. Those having a molecular weight (Mn) of 2,000 to 5,000 are preferred.

  Hindered amine compounds of the above type are commercially available, for example, from Ciba Specialty Chemicals under the product names “TINUVIN 144” and “TINUVIN 770” and from Asahi Denka Kogyo Co., Ltd. under the name “ADK STAB LA-52”.

  The hindered amine light stabilizer is preferably added in an amount of 0.1 to 10% by mass, more preferably 0.2 to 5% by mass, more preferably 0.5 to the mass of the cellulose ester used in the present invention. It is preferable to add ~ 2 mass%. Two or more of these may be used in combination.

(Acid scavenger)
It is preferable that an acid scavenger is contained in the cellulose ester film because it suppresses decomposition by an acid in a high temperature environment. The acid scavenger can be used without limitation as long as it is a compound that reacts with an acid to inactivate the acid, and among them, an epoxy as described in US Pat. Compounds having a group are 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 to 40 moles of ethylene oxide per mole of polyglycol. Glycol, diglycidyl ether of glycerol, etc., metal epoxy compounds (such as those conventionally used in and with vinyl chloride polymer compositions), epoxidized ether condensation products, diphenols of bisphenol A Glycidyl ether (ie, 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 (for example, Butyl epoxy stearate Epoxidized vegetable oils and other unsaturated natural oils, which may be represented and exemplified by compositions of various epoxidized long chain fatty acid triglycerides and the like (eg, epoxidized soybean oil, epoxidized linseed oil, etc.) As epoxidized natural glycerides or unsaturated fatty acids, which generally contain from 12 to 22 carbon atoms). Moreover, EPON 815C and other epoxidized ether oligomer condensation products can also be preferably used as commercially available epoxy group-containing epoxide resin compounds.

  In addition to the above, acid scavengers that can be used include oxetane compounds, oxazoline compounds, alkaline earth metal organic acid salts and acetylacetonate complexes, and paragraphs [0068] to JP-A-5-194788. [0105] are included.

  In the present invention, the acid scavenger is preferably added in an amount of 0.1 to 10% by mass, more preferably 0.2 to 5% by mass, based on the mass of the cellulose ester used in the present invention. Furthermore, it is preferable to add 0.5-2 mass%. Two or more of these may be used in combination.

  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.

(Metal deactivator)
It is also preferred that the cellulose ester film contains a metal deactivator. A metal deactivator means a metal ion deactivating compound that acts as an initiator or a catalyst in an oxidation reaction, and examples thereof include hydrazide compounds, oxalic acid diamide compounds, triazole compounds, and the like. N'-bis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionyl] hydrazine, 2-hydroxyethyl oxalic acid diamide, 2-hydroxy-N- (1H-1,2,4- And triazol-3-yl) benzamide and N- (5-tert-butyl-2-ethoxyphenyl) -N '-(2-ethylphenyl) oxalic acid amide.

  The metal deactivator is preferably added in an amount of 0.0002 to 2% by mass, more preferably 0.0005 to 2% by mass, and more preferably 0.001 to 100% by mass of the resin of the transparent base film. It is preferable to add ~ 1 mass%. Two or more of these may be used in combination.

(Other additives)
For the cellulose ester film, as other additives, for example, dyes, pigments, phosphors, dichroic dyes, retardation control agents, refractive index regulators, gas permeation inhibitors, antibacterial agents, biodegradability imparting agents, etc. May be added.

  And, as a method of incorporating these additives into the cellulose ester film, the respective materials are mixed as solid or liquid, heated and melted and kneaded to obtain a uniform melt, and then cast into a cellulose ester film. Even in the method of forming a film, all materials may be dissolved in advance using a solvent or the like to obtain a uniform solution, and then the solvent may be removed and contained in a mixture of an additive and a cellulose ester film.

The antireflection film according to the present invention is an antireflection film having a transparent film substrate-high refractive index layer-low refractive index layer structure, and the surface of the high refractive index layer when the surface of the high refractive index layer is pressed with a microhardness meter. According to the present invention, by defining the Martens hardness of the surface of the high-refractive index layer of the antireflection film, the Martens hardness (HMs) of 250N / mm ² or more and 350N / mm ² or less is defined. In addition to having high physical strength, it is possible to reduce foreign matter failures and coating unevenness, thereby greatly increasing the antifouling property of the antireflection film and improving the productivity of the film.

Similarly, the antireflection film according to the present invention is an antireflection film having a structure of a transparent film substrate-a high refractive index layer-a low refractive index layer, and when the surface of the low refractive index layer is pressed with a microhardness meter. The Martens hardness (HMs) on the surface of the low refractive index layer is 250 N / mm ² or more and 350 N / mm ² or less. According to the present invention, the Martens hardness on the surface of the low refractive index layer of the antireflection film is reduced. By defining it, it has high physical strength, can reduce foreign matter failure and coating unevenness, can greatly increase the antifouling property of the antireflection film, and improve the productivity of the film it can.

(Polarizer)
The polarizing plate using the antireflection film according to the present invention will be described.

  The polarizing plate can be produced by a general method. The back surface side of the antireflection film of the present invention is subjected to alkali saponification treatment, and a completely saponified polyvinyl alcohol aqueous solution is used on at least one surface of a polarizing film prepared by immersing and stretching the treated antireflection film in an iodine solution. It is preferable to bond them together. The antireflection film may be used on the other surface, or another polarizing plate protective film may be used.

  With respect to the antireflection film of the present invention, the polarizing plate protective film used on the other surface has an in-plane retardation (Ro) of 20 to 70 nm and a thickness direction retardation (Rt) of 100 to 400 nm. It is preferably an optical compensation film (retardation film).

  The retardation values Ro and Rt can be measured using an automatic birefringence meter. For example, using KOBRA-21ADH (manufactured by Oji Scientific Instruments Co., Ltd.), the wavelength can be obtained at 590 nm in an environment of a temperature of 23 ° C. and a humidity of 55% RH.

  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, an unoriented film having an in-plane retardation (Ro) of 0 to 5 nm and a thickness direction retardation (Rt) of -20 to +20 nm is also preferably used.

  By using in combination with the antireflection 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 (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 antireflection 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.

(Image display device)
By incorporating the antireflection film surface of the present invention on the viewing surface side of the image display device, the image display device of the present invention having various visibility can be produced.

  The antireflection film of the present invention is incorporated in a polarizing plate, and is a reflection type, transmission type, transflective LCD or TN type, STN type, OCB type, HAN type, VA type (PVA type, MVA type), IPS type, etc. It is preferably used in LCDs of various drive systems. In addition, the antireflection film of the present invention has significantly less color unevenness in the reflected light of the antireflection layer, and has a low reflectance and excellent flatness, and is a plasma display, field emission display, organic EL display, inorganic EL display, electronic It is also preferably used for various image display devices such as paper.

  In particular, a plasma display in which the antireflection film of the present invention is processed as a front plate filter of a plasma display and is mounted is an image display device having excellent visibility without uneven light interference. In addition, even a 30-inch or larger plasma display image display device has an effect that there is little color unevenness and wavy unevenness, and eyes are not tired even during long-time viewing. The antireflection film of the present invention also has good antistatic properties.

  Examples of the present invention will be described below, but the present invention is not limited thereto.

Example 1
An antireflection film according to the present invention was prepared. The high refractive index layer or the low refractive index layer of the antireflection film may be the surface of the high refractive index layer or the low refractive index layer depending on the composition of the resin composition for forming the high refractive index layer or the low refractive index layer. The value of the surface Martens hardness (HMs) varies, and various antireflection films according to the present invention and various antireflection films for comparison are prepared below.

  First, the transparent film base material was produced by the solution casting film forming method using the following dope composition.

(Dope composition)
Cellulose triacetate (average degree of acetylation 61.0%) 100 parts by weight Triphenyl phosphate 8 parts by weight Ethylphthalyl ethyl glycolate 2 parts by weight Tinuvin 109 (manufactured by Ciba Specialty Chemicals) 1 part by weight Tinuvin 171 (Ciba Specialty Chemicals) 1 part by weight Methylene chloride 430 parts by weight Methanol 90 parts by weight The above materials are put into a sealed container, kept at a temperature of 80 ° C. under pressure, and completely dissolved with stirring to obtain a dope composition. It was.

  Next, the dope composition was filtered, cooled and maintained at a temperature of 33 ° C., cast on a casting belt made of a stainless steel band from a casting die, a web was formed, and the film was peeled off by a peeling roll.

  Thereafter, the web was stretched 1.1 times in the width direction by a tenter, and then dried by a film drying apparatus having a large number of transport rolls arranged in a staggered manner as viewed from the side, and knurling with a height of 10 μm was formed at both ends. A transparent film substrate made of a transparent cellulose triacetate film was prepared by winding up with a winding roll. Here, the transparent film base material had a film thickness of 80 μm, a width of 1.5 m, and a length of 3000 m.

(Hard coat layer)
The above-mentioned transparent film substrate is die-coated with the following coating composition for a hard coat layer, dried at a temperature of 80 ° C., and then cured by irradiating with 0.2 J / cm ² ultraviolet rays with a high-pressure mercury lamp, and having a thickness of 6 μm. A hard coat layer was formed.

(Coating composition for hard coat layer)
Pentaerythritol triacrylate 30 parts by mass Pentaerythritol tetraacrylate 45 parts by mass Urethane acrylate 25 parts by mass (U-4HA, manufactured by Shin-Nakamura Chemical Co., Ltd.)
Photopolymerization initiator 1:
1-hydroxy-cyclohexyl-phenyl-ketone 5 parts by mass (Irgacure 184, manufactured by Ciba Specialty Chemicals Co., Ltd.)
Photopolymerization initiator 2:
2-Methyl-1- [4- (methylthio) phenyl] -2
-Morpholinopropan-1-one 3 parts by mass (Irgacure 907, manufactured by Ciba Specialty Chemicals Co., Ltd.)
0.5 parts by mass of polyoxyethylene oleyl ether (Emulgen 404, manufactured by Kao Corporation)
Propylene glycol monomethyl ether 10 parts by weight Methyl acetate 45 parts by weight Acetone 45 parts by weight Next, on the surface opposite to the hard coat layer of the transparent film substrate, the following back coat layer coating composition was applied to a wet film thickness of 14 μm. Then, it was die-coated so as to be dried at a temperature of 80 ° C., wound up, and provided with a backcoat layer.

(Coating composition for back coat layer)
Diacetylcellulose 0.6 parts by weight Acetone 35 parts by weight Methyl ethyl ketone 35 parts by weight Methanol 35 parts by weight 2% methanol dispersion of silica particles 16 parts by weight (KE-P30, manufactured by Nippon Shokubai Co., Ltd.)
(Preparation of antireflection film 1)
The antireflective film 1 was produced by applying the following high refractive index layer and low refractive index layer in this order on the surface of the hard coat layer produced above.

(Preparation of high refractive index layer 1)
On the hard coat layer prepared above, the following coating composition 1 for a high refractive index layer is die-coated, dried at a temperature of 50 ° C. for 1 minute, and then cured by irradiation with ultraviolet rays of 0.1 J / cm ² to obtain a thickness. A high refractive index layer 1 having a thickness of 130 nm was provided.

(Coating composition 1 for high refractive index layer)
25 parts by mass of zinc antimonate sol (CX-Z610M-F2, manufactured by Nissan Chemical Industries, Ltd.)
30 parts by mass of dioxane glycol diacrylate (NK ester A-DOG: manufactured by Shin-Nakamura Chemical Co., Ltd.)
2 parts by mass of photopolymerization initiator 1 (Irgacure 184: manufactured by Ciba Specialty Chemicals Co., Ltd.)
3 parts by weight of photopolymerization initiator 2 (Irgacure 907: Ciba Specialty Chemicals Co., Ltd.)
3-Methacryloyloxypropyltrimethoxysilane 5 parts by mass (KBM-503, manufactured by Shin-Etsu Chemical Co., Ltd.)
5 parts by mass of 10% propylene glycol monomethyl ether solution of polyoxyalkylenedimethylpolysiloxane copolymer (FZ-2207, manufactured by Toray Dow Corning)
Propylene glycol monomethyl ether 360 parts by mass Isopropyl alcohol 360 parts by mass Methyl ethyl ketone 200 parts by mass (Measurement of Martens hardness)
For the high refractive index layer 1 formed on the surface of the hard coat layer, the Martens hardness (HMs) on the surface of the high refractive index layer 1 was measured using a micro hardness meter.

  That is, for the high refractive index layer 1 formed on the hard coat layer surface, a micro hardness tester (trade name, DUH-211, manufactured by Shimadzu Corporation) using a Vickers indenter and a triangular pyramid indenter whose ridgeline angle is 115 degrees. ) Was used to create a load test force-indentation depth curve when the indenter was pushed into the surface of the high refractive index layer 1 to a thickness of about 1/10 of the film thickness of the high refractive index layer 1. The indentation depth from the 50% value to the 90% value of the maximum load test force (Fmax) obtained from the load test force-indentation depth curve for the high refractive index layer 1 is proportional to the square root of the load test force. From the inclination (m), the value of the Martens hardness (HMs) of the surface of the high refractive index layer 1 defined by the following formula was calculated. The obtained results are shown in Table 1 below.

HMs = 1 / (26.43 m ² )
(Preparation of low refractive index layer 1)
Next, on the surface of the high refractive index layer 1, the following coating composition 1 for low refractive index layer is die-coated, dried at a temperature of 50 ° C. for 1 minute, and then irradiated with ultraviolet rays at 0.1 J / cm ^2. The antireflective film 1 was prepared by providing the low refractive index layer 1 so as to have a thickness of 80 nm by further thermosetting at a temperature of 120 ° C. for 1 minute.

(Coating composition 1 for low refractive index layer)
Tetraethoxysilane hydrolyzate 1 70 parts by mass Hollow silica-based particle dispersion 1 40 parts by mass 3-acryloxypropyltrimethoxysilane 3 parts by mass (KBM5103: manufactured by Shin-Etsu Chemical Co., Ltd.)
6 parts by mass of 10% isopropyl alcohol solution of aluminum ethyl acetoacetate diisopropylate (ALCH, manufactured by Kawaken Fine Chemical Co., Ltd.)
α-Butyl-ω- [3- {2,2-bis (hydroxymethyl)
Butoxy} propyl] polydimethylsiloxane 10% isopropyl alcohol solution 2 parts by mass (Silaplane FM-DA21, manufactured by Chisso Corporation)
Propylene glycol monomethyl ether 450 parts by weight Isopropyl alcohol 450 parts by weight (Preparation of tetraethoxysilane hydrolyzate 1)
Tetraethoxysilane hydrolyzate 1 was prepared by mixing 230 g of tetraethoxysilane and 440 g of ethanol, adding 120 g of 2% aqueous acetic acid solution thereto, and then stirring in a water bath at 25 ° C. for 20 hours.

(Preparation of hollow silica particle dispersion 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 with a solid content concentration of 20% by mass (step 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 on which the first silica coating layer was formed was obtained by adding 3000 g (concentration: 3.5% by mass) (step b).

  Next, 1125 g of pure water is added to 500 g of the core particle dispersion liquid on which the first silica coating layer having a solid content concentration of 13 mass% is formed by washing with an ultrafiltration membrane, and concentrated hydrochloric acid (35.5%) is further added dropwise. The pH was adjusted to 1.0 and dealumination was performed.

Next, while adding 10 L of hydrochloric acid aqueous solution of pH 3 and 5 L of pure water, the aluminum salt dissolved in the ultrafiltration membrane was separated, and SiO _2. A dispersion of Al 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, 1750 g of ethanol, and 626 g of 28% ammonia water was heated to 35 ° C., and then 104 g of ethyl silicate (SiO ₂ 28 mass%) was added. The surface of the porous particles on which the silica coating layer was formed was coated with a hydrolyzed polycondensate of ethyl silicate to form a second silica coating layer. Next, a dispersion 1 of hollow silica particles having a solid content concentration of 20% by mass was prepared by replacing the solvent with ethanol using an ultrafiltration membrane.

The thickness of the first silica coating layer of the hollow silica-based particles was 3 nm, the average particle size was 45 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.

Example 2
(Preparation of antireflection film 2)
The antireflection film 2 is produced in the same manner as in Example 1, except that the following high refractive index layer is used instead of the coating composition 1 for high refractive index layer, except for the case of Example 1. The coating composition 2 is used.

(High refractive index layer coating composition 2)
35 parts by mass of zinc antimonate sol methanol dispersion (CX-Z610M-F2, manufactured by Nissan Chemical Industries, Ltd.)
Pentaerythritol triacrylate 20 parts by mass Pentaerythritol tetraacrylate 35 parts by mass Photopolymerization initiator 1 3 parts by mass (Irgacure 184: manufactured by Ciba Specialty Chemicals Co., Ltd.)
Photopolymerization initiator 2 4 parts by mass (Irgacure 907: Ciba Specialty Chemicals Co., Ltd.)
3-Methacryloyloxypropyltrimethoxysilane 5 parts by mass (KBM-503, manufactured by Shin-Etsu Chemical Co., Ltd.)
5 parts by mass of 10% propylene glycol monomethyl ether solution of polyoxyalkylenedimethylpolysiloxane copolymer (FZ-2207, manufactured by Toray Dow Corning)
Propylene glycol monomethyl ether 360 parts by mass Isopropyl alcohol 360 parts by mass Methyl ethyl ketone 200 parts by mass (Measurement of Martens hardness)
For the high refractive index layer 2 formed on the surface of the hard coat layer, the Martens hardness (HMs) on the surface of the high refractive index layer 2 was measured using a micro hardness meter in the same manner as in Example 1. The obtained results are shown in Table 1 below.

Example 3
(Preparation of antireflection film 3)
The antireflection film 3 is produced in the same manner as in Example 1. The difference from Example 1 is that the following high refractive index layer is used instead of the coating composition 1 for high refractive index layer. The coating composition 3 is used.

(High refractive index layer coating composition 3)
Ditrimethylolpropane triacrylate 15 parts by mass Dioxane glycol diacrylate 40 parts by mass (NK ester A-DOG, manufactured by Shin-Nakamura Chemical Co., Ltd.)
2 parts by mass of photopolymerization initiator 1 (Irgacure 184: manufactured by Ciba Specialty Chemicals Co., Ltd.)
3 parts by weight of photopolymerization initiator 2 (Irgacure 907: Ciba Specialty Chemicals Co., Ltd.)
5 parts by mass of 10% propylene glycol monomethyl ether solution of polyoxyalkylenedimethylpolysiloxane copolymer (FZ-2207, manufactured by Toray Dow Corning)
Acetone 250 parts by weight Methyl ethyl ketone 200 parts by weight Cyclohexanone 50 parts by weight (Measurement of Martens hardness)
For the high refractive index layer 3 formed on the surface of the hard coat layer, the Martens hardness (HMs) on the surface of the high refractive index layer 3 was measured using a micro hardness meter in the same manner as in Example 1. The obtained results are shown in Table 1 below.

Comparative Example 1
(Preparation of comparative antireflection film 1)
For comparison, an antireflection film 1 for comparison is produced in the same manner as in Example 1, except that the coating composition 1 for the high refractive index layer is different from that in Example 1. The comparative high refractive index layer coating composition 1 described below was used to form the comparative high refractive index layer 1, and the following comparative coating composition 1 was used instead of the low refractive index layer coating composition 1. The low refractive index layer 1 for comparison is formed using the coating composition 1 for low refractive index layer.

(Coating composition 1 for high refractive index layer for comparison)
Dimethylolpropane triacrylate 15 parts by mass Dioxane glycol diacrylate 40 parts by mass (NK ester A-DOG: manufactured by Shin-Nakamura Chemical Co., Ltd.)
2 parts by mass of photopolymerization initiator 1 (Irgacure 184: manufactured by Ciba Specialty Chemicals Co., Ltd.)
3 parts by weight of photopolymerization initiator 2 (Irgacure 907: Ciba Specialty Chemicals Co., Ltd.)
5 parts by mass of 10% propylene glycol monomethyl ether solution of polyoxyalkylenedimethylpolysiloxane copolymer (FZ-2207, manufactured by Toray Dow Corning)
Acetone 250 parts by weight Methyl ethyl ketone 200 parts by weight Cyclohexanone 50 parts by weight (Measurement of Martens hardness)
For the comparative high refractive index layer 1 formed on the hard coat layer surface, the Martens hardness (HMs) of the comparative high refractive index layer 1 surface was measured using a micro hardness tester as in the case of Example 1 above. Measured. The obtained results are shown in Table 1 below.

(Comparative coating composition for low refractive index layer 1)
Tetraethoxysilane hydrolyzate 1 70 parts by mass Hollow silica-based particle dispersion 1 40 parts by mass 3-acryloxypropyltrimethoxysilane 3 parts by mass (KBM5103: manufactured by Shin-Etsu Chemical Co., Ltd.)
α-Butyl-ω- [3- {2,2-bis (hydroxymethyl)
Butoxy} propyl] polydimethylsiloxane 10% isopropyl alcohol solution 2 parts by mass (Silaplane FM-DA21, manufactured by Chisso Corporation)
Propylene glycol monomethyl ether 450 parts by weight Isopropyl alcohol 450 parts by weight Comparative Example 2
(Preparation of comparative antireflection film 2)
For comparison, an antireflection film 1 for comparison is produced in the same manner as in the case of Comparative Example 1, except that the coating composition 1 for high refractive index layer is different from the case of Comparative Example 1 above. The comparative high refractive index layer 2 is formed using the following comparative high refractive index layer coating composition 2.

(Coating composition 2 for high refractive index layer for comparison)
Trimethylolpropane triacrylate 20 parts by mass Dipentaerythritol hexaacrylate 60 parts by mass Photopolymerization initiator 1 6 parts by mass (Irgacure 184: manufactured by Ciba Specialty Chemicals)
6 parts by mass of photopolymerization initiator 2 (Irgacure 907: Ciba Specialty Chemicals Co., Ltd.)
Colloidal silica methyl ethyl ketone dispersion 30 parts by mass (MEK-ST, manufactured by Nissan Chemical Industries)
Propylene glycol monomethyl ether 250 parts by mass Isopropyl alcohol 360 parts by mass Methyl ethyl ketone 120 parts by mass (Measurement of Martens hardness)
For the comparative high refractive index layer 2 formed on the hard coat layer surface, the Martens hardness (HMs) of the comparative high refractive index layer 2 surface was measured using a micro hardness tester in the same manner as in Example 1 above. Measured. The obtained results are shown in Table 1 below.

(Evaluation of antireflection film)
About each of the antireflection films of Examples 1 to 3 and Comparative Examples 1 and 2 produced as described above, solvent resistance (solvent penetration resistance), antifouling property, crack resistance, and occurrence of foreign matter failure Each was evaluated, and the obtained results are shown in Table 1 below.

(Solvent resistance)
The surface of each of the antireflection film samples of Examples 1 to 3 and Comparative Examples 1 and 2 was strongly rubbed 10 times with a woven fabric impregnated with ethanol (trade name, Bencott, manufactured by Asahi Kasei Co., Ltd.) and then visually observed. Evaluation was performed according to the following criteria.

○: No change △: Some peel slightly ×: Peel (antifouling)
The surface of each antireflective film sample was contaminated with an oily red marking pen (magic ink, oily, very thick, manufactured by Teranishi Chemical Co., Ltd.), 18 hours later, wiped with gauze dipped in petroleum benzine, and then ethanol Washed with, lightly wiped with dry gauze, the state of contamination was observed, and the antifouling property was evaluated according to the following criteria.

◎: No trace of contamination is observed and the marking pen ink is repelled very well ○: No trace of contamination is observed △: Trace of contamination is faintly observed X: Trace of contamination is clearly recognized (Crack resistance)
Samples of each antireflection film are stored using a cycle thermo tester for 24 hours under conditions of a temperature of 80 ° C. and a humidity of 20% RH, and under conditions of a temperature of 80 ° C. and a humidity of 80% RH for 24 hours, respectively. This was repeated for 17 days. Next, the sample of each antireflection film after 17 days was wound around a round bar having a diameter of 5 mm and a diameter of 10 mm, and the occurrence of cracks was observed and evaluated according to the following criteria. In addition, it shows that the tolerance of a crack is so weak that the crack has generate | occur | produced on the conditions with a large diameter of a round bar.

◎: No cracks occurred when wound on a round bar of any diameter ○: When wound on a round bar with a diameter of 5 mm, there was a trace of winding △: When wound on a round bar with a diameter of 5 mm A crack occurred when wound on a round bar with a diameter of 10 mm (occurrence of foreign matter failure)
With respect to each antireflection film sample, the number of foreign matter failures with a size of 50 μm or more per 10 cm 2 of the film was counted visually and with an optical microscope, and converted to the number per 1 m ² . The occurrence of foreign object failure was evaluated according to the following criteria.

A: A foreign matter failure with a size of 50 μm or more observed visually and with an optical microscope
Less than 3 / m ² ○: Foreign matter failure of 50 μm or larger observed visually and with an optical microscope
3 / m ² or more and less than 5 / m ² Δ: Foreign matter failure having a size of 50 μm or more observed visually and with an optical microscope
5 pieces / m ² or more and less than 10 pieces / m ² ×: foreign matter failure having a size of 50 μm or more observed visually and with an optical microscope
10 / m ² or more (preparation of polarizing film)
Next, in order to produce a polarizing plate and a liquid crystal display panel using the same using the antireflection films of Examples 1 to 3 and Comparative Examples 1 and 2 according to the present invention, first, a polarizing film is produced. did.

  In the production of the polarizing film, a 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 consisting 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 of 68 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 polarizing film.

(Preparation of polarizing plate)
Next, according to the following Step 1 to Step 5, the polarizing film, each of the antireflection films prepared in Examples 1 to 3 and Comparative Examples 1 and 2, and a cellulose ester film having a commercially available retardation (trade name, Konica Minolta Tac Co., Ltd., manufactured by Konica Minolta Opto Co., Ltd.) was bonded together so that the low refractive index layer was on the outside, and a polarizing plate was produced.

  Step 1: The antireflection films of Examples 1 to 3 and Comparative Examples 1 and 2 and the cellulose ester film were immersed in a 2 mol / L sodium hydroxide solution at a temperature of 50 ° C. for 60 seconds, and then washed with water. It dried and the antireflection film and the cellulose-ester film which saponified the side bonded with a polarizing film were obtained.

  Step 2: The polarizing film was immersed in a polyvinyl alcohol adhesive tank having a solid content of 2% by mass for 1 to 2 seconds.

  Step 3: Gently wipe off the excess adhesive adhering to the polarizing film in Step 2, laminating the cellulose ester film saponified in Step 1 on one side of this polarizing film, and then on the other side of the polarizing film Then, the antireflection film saponified in Step 1 was laminated so that the low refractive index layer was on the outside.

Step 4: pressure 20-30 N / cm ² the polarizing film arranged in the step 3, the conveying speed was pasted at approximately 2m / min.

  Step 5: The polarizing film, the cellulose ester film, and the antireflection film laminated film prepared in Step 4 were dried in an 80 ° C. dryer for 2 minutes to prepare a polarizing plate.

(Production of liquid crystal display panel)
Next, the polarizing plate on the outermost surface of a commercially available liquid crystal display panel (manufactured by NEC, color liquid crystal display, MultiSync, LCD1525J: model name, LA-1529HM) was carefully peeled off, and Examples 1 to 3 and Comparative Example 1 were here. Each of the polarizing plates prepared using the antireflection films of No. 1 and No. 2 was bonded to prepare various liquid crystal display panels. The obtained liquid crystal display panels were evaluated for coating unevenness visibility.

(LCD panel evaluation)
About the various liquid crystal panels obtained as described above, the coating unevenness visibility was evaluated as follows. The obtained results are shown in Table 1 below.

(Application unevenness visibility / display panel)
The polarizing plate on the outermost surface of a commercially available liquid crystal display panel (VA type) was carefully peeled off, and the polarizing plate produced using the antireflection film of Examples 1 to 3 described above, and the reflection of Comparative Examples 1 and 2 Each polarizing plate produced using a prevention film was attached.

  The various liquid crystal display panels obtained as described above are placed on a desk 80 cm high from the floor, and a daylight direct fluorescent lamp (trade name: FLR40S · D is placed on the ceiling 3 m high from the floor. / M-X, manufactured by Matsushita Electric Industrial Co., Ltd.) One set of 40W × 2 was arranged in 10 sets at 1.5 m intervals.

  Here, when the evaluator is in front of the display surface of the liquid crystal panel, the fluorescent lamp is arranged so that the fluorescent lamp comes to the ceiling from the evaluator's overhead to the rear. The liquid crystal panel was tilted 25 ° from the vertical direction with respect to the desk so that a fluorescent lamp was reflected, and the coating unevenness of the liquid crystal display panel sample at that time was evaluated according to the following criteria.

○: Color unevenness due to application is not observed at all on the liquid crystal display panel sample. Δ: Color unevenness due to application is slightly observed on the liquid crystal display panel sample. ×: Color unevenness due to application is observed severely on the liquid crystal display panel sample. Ru

  As is clear from the results of Table 1 above, the antireflection films of Examples 1 to 3 according to the present invention are excellent in solvent resistance, for example, even when a coating liquid having another function is applied to the upper layer, The solvent contained in the coating solution does not penetrate into the lower layer and is excellent in coating property. In addition, the antireflection films of Examples 1 to 3 according to the present invention have high physical strength (crack resistance and scratch resistance) and can reduce foreign matter failure and coating unevenness, thereby preventing the antireflection film from being stained. It was possible to greatly increase the property. And, the larger the production area of the antireflection film, the higher the probability of occurrence of foreign matter failure due to cracks. According to the present invention, the high refractive index layer when the surface of the high refractive index layer is pushed with a microhardness meter. By defining the surface Martens hardness (HMs) within a predetermined range, even if the production area was large, the yield could be reduced and the film productivity could be improved.

  Furthermore, according to the liquid crystal panel which bonded the polarizing plate produced using the antireflection film of Examples 1-3 by this invention, respectively, there was no coating nonuniformity and it was excellent in visibility.

  On the other hand, since the antireflection films of Comparative Examples 1 and 2 have a Martens hardness (HMs) on the surface of the comparative high refractive index layer outside the scope of the present invention, the solvent resistance is poor. The coating property was also inferior. In addition, the antireflection films of Comparative Examples 1 and 2 have inferior physical strength (crack resistance), foreign matter failure cannot be reduced, and the antifouling properties of the antireflection film are also deteriorated. When the production area of the prevention film is increased, the probability of occurrence of a foreign matter failure due to a crack is increased, so that the yield is further deteriorated and the productivity of the film may be lowered.

  Moreover, according to the liquid crystal panel which each bonded the polarizing plate produced using the antireflection film of the comparative examples 1 and 2, the coating nonuniformity generate | occur | produced and it was inferior to visibility.

Example 4
An antireflection film according to the present invention was prepared. Using the transparent film base material which consists of the cellulose triacetate film produced in the said Example 1, the hard-coat layer is formed on the surface similarly to the case of the said Example 1, Moreover, the hard coat of a transparent film base material A back coat layer was formed on the surface opposite to the layer in the same manner as in Example 1.

(Preparation of antireflection film 4)
The high refractive index layer 1 is coated on the surface of the hard coat layer produced in the same manner as in Example 1 above, and the low refractive index layer 1 is applied on the surface of the high refractive index layer 1 above. The antireflection film 4 was prepared by coating in the same manner as in 1.

(Measurement of Martens hardness)
For the low refractive index layer 1 on the surface of the antireflection film 4, the Martens hardness (HMs) on the surface of the low refractive index layer 1 was measured using a micro hardness meter.

  That is, for the low refractive index layer 1 described above, using a microhardness meter (trade name, DUH-211, manufactured by Shimadzu Corporation) using a Vickers indenter and a triangular pyramid indenter whose ridgeline angle is 115 degrees, A load test force-indentation depth curve was created when the indenter was pushed into the surface of the refractive index layer 1 to a thickness of about 1/10 of the thickness of the low refractive index layer 1. The indentation depth from the 50% value to the 90% value of the maximum load test force (Fmax) obtained from the load test force-indentation depth curve for the low refractive index layer 1 is proportional to the square root of the load test force. From the inclination (m), the value of the Martens hardness (HMs) of the surface of the low refractive index layer 1 defined by the following formula was calculated. The obtained results are shown in Table 2 below.

HMs = 1 / (26.43 m ² )
Example 5
(Preparation of antireflection film 5)
The antireflection film 5 is produced in the same manner as in Example 4. The difference from Example 4 is that the following low refractive index layer is used instead of the coating composition 1 for low refractive index layer. The coating composition 2 is used.

(Low refractive index layer coating composition 2)
Tetraethoxysilane hydrolyzate 1 85 parts by mass Hollow silica-based particle dispersion 1 15 parts by mass 3-acryloxypropyltrimethoxysilane 3 parts by mass (KBM5103: manufactured by Shin-Etsu Chemical Co., Ltd.)
10% isopropyl alcohol solution of aluminum ethyl acetoacetate diisopropinate (ALCH: manufactured by Kawaken Fine Chemical Co., Ltd.) 6 parts by mass α-butyl-ω- [3- {2,2-bis (hydroxymethyl)
Butoxy} propyl] polydimethylsiloxane 10% isopropyl alcohol solution 2 parts by mass (Silaplane FM-DA21, manufactured by Chisso Corporation)
450 parts by mass of propylene glycol monomethyl ether 450 parts by mass of isopropyl alcohol (measurement of Martens hardness)
For the low refractive index layer 2 formed on the surface of the high refractive index layer 1, the Martens hardness (HMs) on the surface of the low refractive index layer 2 is measured using a micro hardness tester as in the case of Example 4. It was measured. The obtained results are shown in Table 2 below.

Example 6
(Preparation of antireflection film 3)
The antireflection film 6 is produced in the same manner as in Example 4. The difference from the case of Example 4 is that the following low refractive index layer is used instead of the coating composition 1 for low refractive index layer. The coating composition 3 is used.

(Low refractive index layer coating composition 3)
Tetraethoxysilane hydrolyzate 2 70 parts by mass Hollow silica-based particle dispersion 1 40 parts by mass 3-acryloxypropyltrimethoxysilane 3 parts by mass (KBM5103: manufactured by Shin-Etsu Chemical Co., Ltd.)
α-Butyl-ω- [3- {2,2-bis (hydroxymethyl)
Butoxy} propyl] polydimethylsiloxane 10% isopropyl alcohol solution 2 parts by mass (Silaplane FM-DA21, manufactured by Chisso Corporation)
450 parts by mass of propylene glycol monomethyl ether 450 parts by mass of isopropyl alcohol (measurement of Martens hardness)
For the low refractive index layer 3 formed on the surface of the high refractive index layer 1, the Martens hardness (HMs) on the surface of the low refractive index layer 3 is measured using a micro hardness tester as in the case of Example 4 above. It was measured. The obtained results are shown in Table 2 below.

Comparative Example 3
(Preparation of comparative antireflection film 3)
For comparison, an antireflection film 3 for comparison is produced in the same manner as in Example 4, except that the coating composition 1 for the high refractive index layer is different from that in Example 4. The comparative low refractive index layer coating composition 1 of Comparative Example 1 was used to form the comparative low refractive index layer 1 and the low refractive index layer coating composition 1 was used instead of the above. The comparative low refractive index layer coating composition 1 of Comparative Example 1 was used to form the comparative low refractive index layer 1.

(Measurement of Martens hardness)
For the comparative low refractive index layer 1 on the surface of the comparative antireflective film 3, the Martens hardness (HMs) of the comparative low refractive index layer 1 surface was measured using a microhardness meter in the same manner as in Example 4 above. Measured. The obtained results are shown in Table 2 below.

Comparative Example 4
(Preparation of comparative antireflection film 4)
For comparison, an antireflection film 4 for comparison is produced in the same manner as in the case of Comparative Example 3. The difference from the case of Comparative Example 3 is that the coating composition 1 for comparative low refractive index layer is used. Instead, the comparative low refractive index layer 2 was formed using the following coating composition 2 for comparative low refractive index layer.

(Coating composition 2 for high refractive index layer for comparison)
Tetraethoxysilane hydrolyzate 1 85 parts by mass Hollow silica-based particle dispersion 1 15 parts by mass 3-acryloxypropyltrimethoxysilane 3 parts by mass (KBM5103: manufactured by Shin-Etsu Chemical Co., Ltd.)
6 parts by mass of 10% isopropyl alcohol solution of aluminum ethyl acetoacetate diisopropylate (ALCH, manufactured by Kawaken Fine Chemical Co., Ltd.)
α-Butyl-ω- [3- {2,2-bis (hydroxymethyl)
Butoxy} propyl] polydimethylsiloxane 10% isopropyl alcohol solution 2 parts by mass (Silaplane FM-DA21, manufactured by Chisso Corporation)
450 parts by mass of propylene glycol monomethyl ether 450 parts by mass of isopropyl alcohol (measurement of Martens hardness)
For the comparative low refractive index layer 2 on the surface of the comparative antireflection film 4, the Martens hardness (HMs) of the comparative low refractive index layer 2 surface was measured using a micro hardness tester as in the case of Example 4 above. Measured. The obtained results are shown in Table 2 below.

(Evaluation of antireflection film)
About each antireflection film of Examples 4-6 produced as mentioned above, and Comparative Examples 3 and 4, solvent resistance (solvent penetration resistance), antifouling property, crack resistance, and generation | occurrence | production of a foreign material failure Each was evaluated, and the results obtained are shown in Table 2 below.

(Preparation of polarizing film)
Next, using the antireflection films of Examples 4 to 6 and Comparative Examples 3 and 4 according to the present invention, as in Examples 1 to 3 and Comparative Examples 1 and 2, a polarizing plate, and A liquid crystal display panel using this was produced.

(LCD panel evaluation)
About the various liquid crystal panels obtained as described above, the coating unevenness visibility was evaluated as follows. The obtained results are shown in Table 2 below.

  As is apparent from the results of Table 2 above, the antireflection films of Examples 4 to 6 according to the present invention are excellent in solvent resistance. For example, even when a coating liquid having another function is applied to the upper layer, The solvent contained in the coating solution does not penetrate into the lower layer and is excellent in coating property. In addition, the antireflection films of Examples 4 to 6 according to the present invention have a high physical strength (crack resistance) and can reduce foreign matter failure, thereby greatly increasing the antifouling property of the antireflection film. It was something that could be done. And, the larger the production area of the antireflection film, the higher the probability of occurrence of foreign matter failure due to cracks. According to the present invention, the low refractive index layer when the surface of the low refractive index layer is pushed with a microhardness meter. By defining the surface Martens hardness (HMs) within a predetermined range, even if the production area was large, the yield could be reduced and the film productivity could be improved.

  Furthermore, according to the liquid crystal panel which bonded the polarizing plate produced using the antireflection film of Examples 4-6 by this invention, respectively, there was no coating nonuniformity and it was excellent in visibility.

  On the other hand, the antireflection films of Comparative Examples 3 and 4 are inferior in solvent resistance because the Martens hardness (HMs) on the surface of the comparative high refractive index layer is outside the scope of the present invention. The coating property was also inferior. In addition, the antireflection films of Comparative Examples 3 and 4 have inferior physical strength (crack resistance), cannot reduce foreign matter failure, and the antifouling properties of the antireflection film are also deteriorated. When the production area of the prevention film is increased, the probability of occurrence of a foreign matter failure due to a crack is increased, so that the yield is further deteriorated and the productivity of the film may be lowered.

  Moreover, according to the liquid crystal panel which each bonded the polarizing plate produced using the antireflection film of the comparative examples 3 and 4, the coating nonuniformity generate | occur | produced and it was inferior to visibility.

Claims (5)

An antireflection film having a high refractive index layer having a refractive index higher than that of the transparent film substrate and a low refractive index layer having a refractive index lower than that of the transparent film substrate on the transparent film substrate. The antireflective film characterized by having a Martens hardness (HMs) of the surface of the high refractive index layer when the surface of the layer is pressed with a microhardness meter is 250 N / mm ² or more and 350 N / mm ² or less. .
Here, the Martens hardness (HMs) on the surface of the high refractive index layer is a microhardness meter using a Vickers indenter and a triangular pyramid indenter having an angle between ridges of 115 degrees. In the load test force-indentation depth curve when the indenter is pushed down to approximately 1/10 of the thickness of the refractive index layer, the maximum load test force (Fmax) obtained from the load test force-indentation depth curve ) Is a value defined by the following equation from the slope (m) in which the indentation depth from the 50% value to the 90% value is proportional to the square root of the load test force.
1HMs = 1 / (26.43m ² ) An antireflection film having a high refractive index layer having a refractive index higher than that of the transparent film substrate and a low refractive index layer having a refractive index lower than that of the transparent film substrate on the transparent film substrate, and having a low refractive index. An antireflection film characterized in that the Martens hardness (HMs) of the surface of the low refractive index layer when the surface of the layer is pressed with a microhardness meter is 250 N / mm ² or more and 350 N / mm ² or less. .
In this case, the Martens hardness (HMs) on the surface of the low refractive index layer is a microhardness meter using a Vickers indenter and a triangular pyramid indenter with an angle between ridges of 115 degrees. It is calculated as described above from the value of the maximum load test force (Fmax) obtained from the load test force-indentation depth curve when the indenter is pushed down to approximately 1/10 of the thickness of the rate layer. .   A polarizing plate, wherein the antireflection film according to claim 1 or 2 is bonded to at least one of both surfaces of a polarizer.   A display device comprising the antireflection film according to claim 1.   A display device comprising the polarizing plate according to claim 3.