JP4935393B2 - Antireflection film, and polarizing plate and display device using the same - Google Patents

Description

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

  In recent years, the development of thin and light notebook PCs and thin and large-screen TVs has progressed, and along with this, surface protective films and protective films for polarizing plates used in display devices have become increasingly thinner, larger, and higher in performance. The demand is getting stronger. In particular, a display device (for example, a liquid crystal display, a plasma display, etc.) using a functional film provided with an anti-reflection layer for improving visibility, or provided with an anti-glare layer with an uneven surface to scatter reflected light. Has come to be used a lot.

  Various types of antireflection layers have been improved in performance and performance, and various types of front plates with these functions are bonded to liquid crystal display polarizers, etc. to improve the visibility of the display. A method of imparting a function is used. (For example, refer to Patent Document 1.) These optical films used as the front plate are often provided with an antireflection layer formed by coating, vapor deposition, sputtering, or the like.

  However, when the metal oxide layer constituting the antireflection film is applied, streaky coating unevenness is likely to occur, and improvement thereof has been demanded. In particular, when the width of the base film is 1.4 m or more, coating unevenness is likely to occur, and improvement thereof has been demanded.

Similarly, the color unevenness of the antireflection layer becomes conspicuous when it is widened, and the improvement thereof has been demanded.
JP 2002-182005 A

  Accordingly, an object of the present invention is to provide an antireflection film having improved stripe-like coating unevenness and reflected color unevenness, and a polarizing plate and a display device using the same even with a wide antireflection film. is there.

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

1. In the antireflection film having a hard coat layer and an antireflection layer on at least one surface of the transparent resin film, at least one layer contains an ionic liquid ,
The antireflective layer has a high refractive index layer, the high refractive index layer contains an ionic liquid;
The antireflective film, wherein the high refractive index layer has a refractive index of 1.5 to 2.2 .

  2. 2. The antireflection film as described in 1 above, wherein the antireflection layer has a low refractive index layer, and the low refractive index layer contains hollow silica-based fine particles.

3 . A polarizing plate, wherein the antireflection film according to 1 or 2 is bonded to at least one surface of a polarizer.

4 . 3. A display device comprising the antireflection film described in 1 or 2 or the polarizing plate described in 3 above.

  An object of the present invention is to provide an antireflection film with improved striped coating unevenness and uneven reflection color, and a polarizing plate and a display device using the same even if it is a wide antireflection film.

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

  The antireflection film of the present invention has a hard coat layer and an antireflection layer on at least one surface of a transparent resin film, and at least one layer contains an ionic liquid.

  The ionic liquid used in the present invention is a salt having a melting point lower than room temperature and liquid at room temperature, and room temperature means 25 ° C. In the present invention, at least one of the hard coat layer and the antireflection layer is preferably 0.01 to 30% by mass, more preferably 0.1 to 20% by mass, and still more preferably 0.5 to 10%. It is characterized in that streaky coating unevenness and color unevenness can be improved by the inclusion by mass%.

  An ionic liquid is also called an ionic liquid. Generally, a salt is solid at room temperature, and is known to melt when heated to several hundred degrees. On the other hand, a so-called ionic liquid that is in a liquid state at room temperature in a predetermined combination of organic cation and anion has been found. The reason why this ionic liquid becomes liquid at a temperature near room temperature is presumed to be related to the size of ions and the electrostatic interaction between ions. Furthermore, the ionic liquid has a low vapor pressure, non-volatility, and at the same time has the characteristics of non-combustibility and flame retardancy. This is presumed to be because ions are restrained due to the electrostatic interaction between molecules.

  The inventors of the present invention, in particular, as a result of intensive studies on coating unevenness of the antireflection layer, found that the unevenness of the antireflection layer is reduced by providing a layer containing an ionic liquid. The layer containing the ionic liquid is preferably either a hard coat layer or an antireflection layer, and particularly preferably added to the high refractive index layer. As a result, not only the unevenness of the high refractive index layer is reduced, but also the unevenness of the low refractive index layer is reduced, and it is considered that a uniform antireflection layer is formed. The reason is not well understood, but the high refractive index layer and the low refractive index layer constituting the antireflection layer contain metal oxide particles, and when applying a coating composition containing these, it is applied. The ionic liquid contained in the composition or the inclusion in the adjacent layer is considered to contribute to the reduction of unevenness. There is a possibility that the metal oxide contained in the antireflection layer is uniformly dispersed, which may lead to elimination of unevenness. By containing the ionic liquid, ions of the ionic liquid, the metal oxide, the solvent used, and the binder The metal oxide may be uniformly dispersed due to the dynamic interaction.

  In the present invention, the antireflection layer has a low refractive index layer, the low refractive index layer contains hollow silica particles, or the antireflection layer has a high refractive index layer, and the high refractive index layer It is a preferable aspect to contain an ionic liquid.

  Hereinafter, the present invention will be described in detail.

<Ionic liquid>
The ionic liquid used in the present invention is a compound composed of an organic cation and an anion, and a compound having a melting point of 25 ° C. or lower is preferable. For example, examples of the organic cation include imidazolium, pyridinium, piperidinium, quaternary ammonium, and phosphonium.

  The imidazolium salt is represented by the following general formula (1).

In general formula (1), R < ₁ > -R < ₃ > shows hydrogen, an alkyl group, or an alkoxy group, As an alkyl group or an alkoxy group, it is preferable that it is C1-C20, and 1-8 are especially preferable. Specific examples include 1-ethyl-3-methylimidazolium salt, 1-butyl-3-methylimidazolium salt, 1-hexyl-3-methylimidazolium salt, 1-octyl-3-methylimidazolium salt, 1 -Decyl-3-methylimidazolium salt, 1-dodecyl-3-methylimidazolium salt, 1-tetradecyl-3-methylimidazolium salt, 1-hexadecyl-3-methylimidazolium salt, 1-octadecyl-3-methyl Examples include imidazolium salts, 1-ethyl-2,3-dimethylimidazolium salts, 1-butyl-2,3-dimethylimidazolium salts, 1-hexyl-2,3-dimethylimidazolium salts, and the like. Among these, 1-ethyl-3-methylimidazolium salt and 1-butyl-3-methylimidazolium salt are particularly preferable.

  The pyridinium salt is represented by the following general formula (2).

  In general formula (2), R represents hydrogen, an alkyl group or an alkoxy group, and the alkyl group or alkoxy group preferably has 1 to 20 carbon atoms, and particularly preferably 1 to 8 carbon atoms.

  Specific examples include 1-ethylpyridinium salt, 1-butylpyridinium salt, 1-hexylpyridinium salt and the like. Among these, 1-ethylpyridinium salt and 1-butylpyridinium salt are particularly preferable.

  The quaternary ammonium salt is represented by the following general formula (3).

In general formula (3), R < ₁ > -R < ₄ > shows hydrogen, an alkyl group, or an alkoxy group, As an alkyl group or an alkoxy group, it is preferable that it is C1-C20, and 1-8 are especially preferable.

  Specific examples include aliphatic quaternary ammonium salts. Specific examples include trimethyl-hexylammonium salt, N, N-diethyl-N-methyl-N- (2-methoxyethyl) ammonium salt, trimethylhexylammonium salt, trimethyloctylammonium salt, and the like. In particular, N, N-diethyl-N-methyl-N- (2-methoxyethyl) ammonium salt is preferred.

  It is also possible to use a piperidinium salt represented by the following general formula 4.

  In General Formula (4), R1 to R2 represent hydrogen or an alkyl group, and the alkyl group is preferably an alkyl group having 1 to 20 carbon atoms, particularly preferably 1 to 8.

  In general formulas (1) to (4), it is also possible to use a Zwitterionic ionic liquid having a carboxylic acid group or a sulfonic acid group as part of the alkyl group.

  Further, pyrrolinium salt, phenylindolium salt, alkylindolium salt, alkylcarbazolium salt, pyrazolium salt, pyrrolidinium salt, and the like can also be used.

  Furthermore, it is possible to design the compound obtained by combining with an anion to have a low melting point, and since it has an affinity with an organic solvent, the organic cation is preferably an imidazolium-based, pyridinium-based, or piperidinium-based one. In the quaternary ammonium system, a compound having a long alkyl chain length is preferred. Specifically, 1-ethyl-3-methylimidazolium salt, 1-butyl-3-methylimidazolium salt, 1-hexyl-3-methylimidazolium salt, 1-octyl-3-methylimidazolium salt, 1 -Decyl-3-methylimidazolium salt, 1-dodecyl-3-methylimidazolium salt, 1-tetradecyl-3-methylimidazolium salt, 1-hexadecyl-3-methylimidazolium salt, 1-octadecyl-3-methyl Imidazolium salt, 1-butyl-2,3-dimethylimidazolium salt, 1-hexyl-2,3-dimethylimidazolium salt, 1-butylpyridinium salt, 1-hexylpyridinium salt, trimethyloctylammonium salt, piperidinium salt, etc. Is preferred.

  On the other hand, examples of the anion include lithium ion, bromine ion, chlorine ion, lactate ion, hexafluorophosphate, tetrafluoroborate, bis (trifluoromethanesulfonyl) imide, trifluoromethanesulfonate, and the like.

  In addition, the safety of materials such as toxicity, and the ability to lower the melting point of compounds obtained by combining with organic cations are possible. As anions, lithium ions, bromine ions, chlorine Ions, lactate ions, hexafluorophosphate, bis (trifluoromethanesulfonyl) imide, and trifluoromethanesulfonate are preferable, and lithium ions, bromine ions, chloride ions, and lactate ions are more preferable.

  Specific examples of the ionic liquid include 1-ethyl-3-methylimidazolium bromide, 1-ethyl-3-methylimidazolium chloride, 1-ethyl-3-methylimidazolium lactate, 1-ethyl-3-methylimidazolium. Hexafluorophosphate, 1-butyl-3-methylimidazolium chloride, 1-butyl-3-methylimidazolium bis (trifluoromethanesulfonyl) imide, 1-butyl-3-methylimidazolium hexafluorophosphate, 1-butyl -3-methylimidazolium tetrafluoroborate, 1-butyl-3-methylimidazolium trifluoromethanesulfonate, 1-butyl-3-methylimidazolium lactate, 1-hexyl-3-methylimidazolium bromide, 1- Xyl-3-methylimidazolium chloride, 1-hexyl-3-methylimidazolium hexafluorophosphate, 1-hexyl-3-methylimidazolium tetrafluoroborate, 1-hexyl-3-methylimidazolium trifluoromethanesulfonate 1-octyl-3-methylimidazolium chloride, 1-octyl-3-methylimidazolium hexafluorophosphate, 1-decyl-3-methylimidazolium chloride, 1-dodecyl-3-methylimidazolium chloride, 1- Hexadecyl-3-methylimidazolium chloride, 1-octadecyl-3-methylimidazolium chloride, 1-ethyl-2,3-dimethylimidazolium bromide, 1-ethyl-2,3-dimethylimidazolium Chloride, 1-butyl-2,3-dimethylimidazolium chloride, 1-butyl-2,3-dimethylimidazolium bromide, 1-butyl-2,3-dimethylimidazolium tetrafluoroborate, 1-hexyl-2,3 -Dimethylimidazolium bromide, 1-hexyl-2,3-dimethylimidazolium chloride, 1-hexyl-2,3-dimethylimidazolium tetrafluoroborate, 1-hexyl-2,3-dimethylimidazolium trifluoromethanesulfonate 1-ethylpyridinium bromide, 1-ethylpyridinium chloride, 1-butylpyridinium bromide, 1-butylpyridinium chloride, 1-butylpyridinium hexafluorophosphate, 1-butylpyridinium trifluoro Methane sulfonate, 1-hexylpyridinium bromide, 1-hexylpyridinium chloride, 1-hexylpyridinium hexafluorophosphate, 1-hexylpyridinium tetrafluoroborate, 1-hexylpyridinium trifluoromethanesulfonate, N, N-diethyl -N-methyl-N- (2-methoxyethyl) ammonium tetrafluoroborate, N, N-diethyl-N-methyl-N- (2-methoxyethyl) ammonium bis (trifluoromethanesulfonyl) imide, trimethylhexylammonium bis (Trifluoromethanesulfonyl) imide, trimethyloctylammonium bis (trifluoromethanesulfonyl) imide, trimethylpropylammonium bis (trifluoromethane Sulfonyl) imide, 2-methyl-1-pyrrolinium hexafluoroborate, 1-ethyl-2-phenylindolium hexafluoroborate, 1,2-dimethylindolium hexafluoroborate, 1-ethylcarbazolium hexafluoroborate 1-methylpyrazolium hexafluoroborate, 1-methylpyrrolidinium hexafluoroborate and the like.

  Furthermore, from the viewpoint of material safety and affinity with an organic solvent, the following compounds are preferred as the ionic liquid. Specific examples include 1-ethyl-3-methylimidazolium lactate, 1-ethyl-3-methylimidazolium hexafluorophosphate, 1-butyl-3-methylimidazolium bis (trifluoromethanesulfonyl) imide, 1-butyl. -3-methylimidazolium hexafluorophosphate, 1-butyl-3-methylimidazolium trifluoromethanesulfonate, 1-butyl-3-methylimidazolium lactate, 1-hexyl-3-methylimidazolium hexafluorophosphate 1-hexyl-3-methylimidazolium trifluoromethanesulfonate, 1-octyl-3-methylimidazolium chloride, 1-octyl-3-methylimidazolium hexafluorophosphate, 1-decyl- -Methylimidazolium chloride, 1-dodecyl-3-methylimidazolium chloride, 1-hexadecyl-3-methylimidazolium chloride, 1-octadecyl-3-methylimidazolium chloride, 1-hexyl-2,3-dimethylimidazolium Bromide, 1-hexyl-2,3-dimethylimidazolium chloride, 1-hexyl-2,3-dimethylimidazolium trifluoromethanesulfonate, 1-butylpyridinium bromide, 1-butylpyridinium chloride, 1-butylpyridinium hexafluoro Phosphate, 1-butylpyridinium trifluoromethanesulfonate, 1-hexylpyridinium bromide, 1-hexylpyridinium chloride, 1-hexylpyridinium hexaful Lophosphate, 1-hexylpyridinium trifluoromethanesulfonate, N, N-diethyl-N-methyl-N- (2-methoxyethyl) ammonium bis (trifluoromethanesulfonyl) imide, trimethylhexylammonium bis (trifluoromethanesulfonyl) imide Trimethyloctylammonium bis (trifluoromethanesulfonyl) imide and trimethylpropylammonium bis (trifluoromethanesulfonyl) imide are preferable.

  A commercially available ionic liquid can be preferably used.

  In the present invention, at least one of the hard coat layer and the antireflection layer is preferably 0.01 to 30% by mass, more preferably 0.1 to 20% by mass, and still more preferably 0.5 to 10% by mass. By containing, striped coating unevenness and color unevenness are improved. In particular, it is preferable to contain the antireflective layer in the high refractive index layer because it exhibits a remarkable effect in improving coating properties.

  As described above, in the present invention, the ionic liquid is preferably a compound composed of an organic cation and an anion, and the melting point of the compound is preferably 25 ° C. or lower. From the viewpoint of handling at the time of addition of the ionic liquid and stability in the coating solution, the melting point of the ionic liquid is more preferably 20 ° C. or less, and further preferably 10 ° C. or less.

  In the present invention, the boiling point of the ionic liquid is preferably 400 ° C. or higher. More preferably, it is 450 degreeC or more, More preferably, it is 500 degreeC or more. When the boiling point was less than 400 ° C., the stability of the ionic liquid during long-term storage sometimes decreased.

  In the present invention, the molecular weight of the ionic liquid is preferably less than 1000, more preferably less than 750, and still more preferably less than 500. If the molecular weight of the ionic liquid is less than 1000, the liquid viscosity is easy to control and the coating property is good.

<Antireflection layer>
Next, the antireflection layer provided on the transparent resin film will be described.

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

[Hard coat layer: Actinic radiation curable resin layer]
In the antireflection film of the present invention, a layer containing an actinic radiation curable resin is provided as a hard coat layer between the transparent resin film and the antireflection layer.

  The “active ray curable resin layer” according to the present invention is a layer mainly composed of a resin that is cured through a crosslinking reaction or the like by irradiation with active rays such as ultraviolet rays or electron beams (also referred to as “active energy rays”). Say. 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-A-59-151110 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 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 US Pat. 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.

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

  Examples of specific compounds include trimethylolpropane triacrylate, ditrimethylolpropane tetraacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol hexaacrylate, alkyl-modified dipentaerythritol pentaacrylate, and the like. .

  The cured resin layer thus obtained may contain fine particles of an inorganic compound or an organic compound in order to adjust the scratch resistance, slipperiness and refractive index.

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

  Organic particles include polymethacrylic acid methyl acrylate resin powder, acrylic styrene resin powder, polymethyl methacrylate resin powder, silicon resin powder, polystyrene resin powder, polycarbonate resin powder, benzoguanamine resin powder, melamine resin powder. Polyolefin resin powder, polyester resin powder, polyamide resin powder, polyimide resin powder, or polyfluoroethylene resin powder can be added to the ultraviolet curable resin composition. Particularly preferred are 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 fine particle powders is preferably 0.01 to 5 μm, more preferably 0.1 to 5.0 μm, and particularly preferably 0.1 to 4.0 μm. Moreover, it is preferable to contain 2 or more types of microparticles | fine-particles from which a particle size differs. The proportion of the ultraviolet curable resin composition and the fine particles is desirably blended so as to be 0.1 to 30 parts by mass with respect to 100 parts by mass of the resin composition.

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

As a light source for curing an ultraviolet curable resin by a photocuring reaction to form a cured film layer, any light source that generates ultraviolet rays 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 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 .

  Moreover, when irradiating actinic radiation, it is preferable to carry out while applying tension | tensile_strength in the conveyance direction of a film, More preferably, it is performing applying tension | tensile_strength also 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 hard coat layer coating solution may contain a solvent, or may be appropriately contained and diluted as necessary. Examples of the organic solvent contained in the coating solution include hydrocarbons (toluene, xylene), alcohols (methanol, ethanol, isopropanol, butanol, cyclohexanol), ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone), These may be appropriately selected from esters (methyl acetate, ethyl acetate, methyl lactate), glycol ethers, and other organic solvents, or may be used by mixing them. Propylene glycol monoalkyl ether (1 to 4 carbon atoms of the alkyl group) or propylene glycol monoalkyl ether acetate ester (1 to 4 carbon atoms of the alkyl group) is 5% by mass or more, more preferably 5 to 80%. It is preferable to use the organic solvent containing at least mass%.

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

  Further, the hard coat layer preferably contains a silicone surfactant or a polyoxyether compound. These improve applicability | paintability and it is preferable to add these components in 0.01-3 mass% with respect to the solid content component in a coating liquid.

(Surfactant)
The silicone surfactant used in the present invention will be described.

  The silicone surfactant used in the present invention includes silicone oil.

  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.

  Of these, nonionic surfactants having a hydrophobic group composed of dimethylpolysiloxane and a hydrophilic group composed of polyoxyalkylene are preferred.

  A nonionic surfactant is a generic term for surfactants that do not have a group capable of dissociating into ions in an aqueous solution. In addition to a hydrophobic group, a hydrophilic group includes a hydroxyl group of a polyhydric alcohol, a polyoxyalkylene chain (poly Oxyethylene) or the like as a hydrophilic group. The hydrophilicity becomes stronger as the number of alcoholic hydroxyl groups increases and as the polyoxyalkylene chain (polyoxyethylene chain) becomes longer.

  Next, silicone oil will be described. Silicone oils can be broadly classified into straight silicone oils and modified silicone oils depending on the type of organic group bonded to silicon atoms. Straight silicone oil refers to those bonded with a methyl group, a phenyl group, or a hydrogen atom 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 Straight silicone oil 1-1. Non-reactive silicone oil: dimethyl, methylphenyl substitution, etc. 1-2. Reactive silicone oil: methyl hydrogen substitution, etc. Modified silicone oil Modified silicone oil was born by introducing various organic groups into dimethyl silicone oil 2-1. Non-reactive silicone oil: alkyl, alkyl / aralkyl, alkyl / polyether, polyether, higher fatty acid ester substitution, etc.
Alkyl / aralkyl-modified silicone oil is a silicone oil in which a part of methyl group of dimethyl silicone oil is replaced with a long-chain alkyl group or a phenylalkyl group,
Polyether-modified silicone oil is a silicone-based polymer surfactant in which hydrophilic polyoxyalkylene is introduced into hydrophobic dimethyl silicone,
Higher fatty acid-modified silicone oil is a silicone oil in which a part of methyl group of dimethyl silicone oil is replaced with higher fatty acid ester,
Amino-modified silicone oil is a silicone oil having a structure in which a part of methyl group of silicone oil is substituted with 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 replaced 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 2-2. Reactive silicone oil: Of these, amino, epoxy, carboxyl, alcohol substitution, etc. Of these, polyether-modified silicone oil is preferable from the viewpoint of the object and effect of the present invention. The number average molecular weight of the polyether-modified silicone oil is, for example, 1,000 to 100,000, preferably 2000 to 50,000.

  Specific examples of these silicone surfactants (silicone oils) include, for example, SH200, BY16-873, PRX413 (dimethylsilicone oil; manufactured by Toray Dow Corning Silicone Co., Ltd.), SH510, SH550, SH710 (methylphenyl). Silicone oil; manufactured by Toray Dow Corning Silicone Co., Ltd.), SH203, SH230, SF8416 (alkyl-modified silicone oil; manufactured by Toray Dow Corning Silicone Co., Ltd.), SF8417, BY16-208, BY16-209, BY16- 849, BY16-872 (amino-modified silicone oil; manufactured by Toray Dow Corning Silicone Co., Ltd.), SF8411, SF8413, BY16-855D (epoxy-modified silicone oil; Toray Dowconi) Manufactured by Silicone Co., Ltd.), BY16-848, BY16-201 (alcohol-modified silicone oil; manufactured by Toray Dow Corning Silicone Co., Ltd.), BY16-152 (methacrylate-modified silicone oil; Toray Dow Corning Silicone) FZ-2222, FZ-2207 (dimethylpolysiloxane / polyethylene oxide linear block copolymer; FZ series manufactured by Nihon Unicar), KF-101, KF-102, KF-105 (epoxy-modified) Silicone oil; manufactured by Shin-Etsu Chemical Co., Ltd.), KF-8008, KF-861, KF-8002 (amino-modified silicone oil; manufactured by Shin-Etsu Chemical Co., Ltd.), KF-6001, KF-6002 (carbinol-modified silicone oil; Shin-Etsu Chemical) Manufactured by Kogyo Co., Ltd.), X-22-16 A, X-22-2404 (methacryl-modified silicone oil; manufactured by Shin-Etsu Chemical Co., Ltd.), KF-412, KF-414 (alkyl-modified silicone oil; manufactured by Shin-Etsu Chemical Co., Ltd.), KF-910 (ester-modified silicone oil; Shin-Etsu) Chemical Industry), SH3749, SH3748, SH8400, SF8410, SF8427, BY16-004, SF8428, SH3771, SH3746, BY16-036 (polyether-modified silicone oil; manufactured by Toray Dow Corning Silicone Co., Ltd.), BYK- UV3500, BYK-UV3510, BYK-333, BYK-331, BYK-337 (manufactured by polyether-modified silicone oil Big Chemi-Japan), TSF4440, TSF4445, TSF4446, TSF4452, TSF 4460 (polyether-modified silicone oil; manufactured by GE Toshiba Silicone), KF-351, KF-351A, KF-352, KF-353, KF-354, KF-355, KF-615, KF-618, KF-945, Examples thereof include, but are not limited to, KF-6004 (polyether-modified silicone oil; manufactured by Shin-Etsu Chemical Co., Ltd.).

  On the other hand, examples of nonionic polyoxyether compounds include polyoxyethylene alkyl ether compounds such as polyoxyethylene alkyl ether, polyoxyethylene lauryl ether, polyoxyethylene cetyl ether, polyoxyethylene stearyl ether, and polyoxyethylene. Examples thereof include polyoxyalkylphenyl ether compounds such as nonylphenyl ether and polyoxyethylene octylphenyl ether, polyoxyalkylene alkyl ether, polyoxyethylene higher alcohol ether, polyoxyethylene octyldodecyl ether and the like.

  As commercially available products of polyoxyethylene alkyl ether, Emulgen 1108, Emulgen 1118S-70 (manufactured by Kao Corporation), and as commercially available products of polyoxyethylene lauryl ether, Emulgen 103, Emulgen 104P, Emulgen 105, Emulgen 106, Emulgen 108 , Emulgen 109P, Emulgen 120, Emulgen 123P, Emulgen 147, Emulgen 150, Emulgen 130K (above Kao), polyoxyethylene cetyl ether, Emulgen 210P, Emulgen 220 (above Kao), Polyoxy Commercially available products of ethylene stearyl ether include Emulgen 220, Emulgen 306P (manufactured by Kao Corporation), and commercially available products of polyoxyalkylene alkyl ether include Emulgen. S-106, Emulgen LS-110, Emulgen LS-114, Examples of commercially available Emulgen MS-110 (Kao Corporation) Polyoxyethylene higher alcohol ethers, Emulgen 705, Emulgen 707, Emulgen 709, and the like. Among these nonionic polyoxyether compounds, a polyoxyethylene oleyl ether compound is preferable, and a compound generally represented by the general formula (5).

Formula _{(5) C 18 H 35 -O} (C 2 H 4 O) nH
In the formula, n represents 2 to 40.

  The average addition number (n) of ethylene oxide with respect to the oleyl part is 2 to 40, preferably 2 to 10. The compound of the general formula (5) can be obtained by reacting ethylene oxide and oleyl alcohol.

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

  In addition, () represents the number of 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 In order to obtain the effects of the present invention, it is preferably 0.20: 1.0.

  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, and more preferably 0.8% by mass. It is 2 mass%-4.0 mass%, and the anti-reflective film especially excellent in chemical-resistance, surface hardness, and wet heat resistant adhesion is obtained in this range.

  Further, a fluorine surfactant, an acrylic copolymer, an acetylene glycol compound or other nonionic surfactant, a radical polymerizable nonionic surfactant, or the like may be used in combination.

  Commercially available fluorosurfactants include Fluorard FC-430 and FC170 manufactured by Sumitomo 3M Limited, MegaFuck F177, F471, and F482 manufactured by Dainippon Ink and Chemicals, Inc. Examples of the acrylic copolymer include BYK-361N and BYK-358N manufactured by BYK Japan.

  Other nonionic surfactants include polyoxyethylene monolaurate, polyoxyethylene monostearate, polyoxyalkyl ester compounds such as polyoxyethylene monooleate, sorbitan monolaurate, sorbitan monostearate, sorbitan mono And sorbitan ester compounds such as oleate.

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

  Examples of the radical polymerizable nonionic surfactant include polyoxyalkylenes such as “RMA-564”, “RMA-568”, “RMA-1114” [trade name, manufactured by Nippon Emulsifier Co., Ltd.]. Examples thereof include alkylphenyl ether (meth) acrylate-based 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 fine 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. Or a pigment or the like) or an electromagnetic wave blocking agent or an infrared absorbing agent or the like to have the respective functions.

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

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

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

(Low refractive index layer)
The refractive index of the low refractive index layer according to the present invention is preferably lower than the refractive index of the transparent resin film as the support, and is preferably in the range of 1.30 to 1.45 at 23 ° C. and a wavelength of 550 nm.

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

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

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

General formula (OSi-1): Si (OR) ₄
(In the formula, R is an alkyl group, preferably an alkyl group having 1 to 4 carbon atoms.)
In addition, a silane coupling agent, a curing agent, a surfactant and the like may be added as necessary.

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

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

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

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

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

  In addition, the pore volume of such porous particles can be determined by a mercury intrusion method. Examples of the contents of the hollow particles include a solvent, a gas, and a porous substance used at the time of preparing the particles. The solvent may contain an unreacted particle precursor used when preparing the hollow particles, the catalyst used, and the like. Examples of the porous substance include those composed of the compounds exemplified for the porous particles. These contents may be composed of a single component or may be a mixture of a plurality of components.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

  In the organic silicon compound represented by the general formula (OSi-1), R represents an alkyl group having 1 to 4 carbon atoms.

  Specifically, tetramethoxysilane, tetraethoxysilane, tetraisopropoxysilane and the like are preferably used.

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

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

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

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

Rf represents-(C _a H _b F _c )-, a is an integer of 1 to 12, b + c is 2a, b is an integer of 0 to 24, and c is an integer of 0 to 24. Such Rf is preferably a group having a fluoroalkylene group and an alkylene group. Specifically, as such a fluorine-containing silicone compound, (MeO) ₃ SiC ₂ H ₄ C ₂ F ₄ C ₂ H ₄ Si (MeO) ₃ , (MeO) ₃ SiC ₂ H ₄ C ₄ F ₈ C ₂ H ₄ Si (MeO) ₃ , (MeO) ₃ SiC ₂ H ₄ C ₆ F ₁₂ C ₂ H ₄ Si (MeO) ₃ , (H ₅ C ₂ O) ₃ SiC ₂ H ₄ C ₄ F ₈ C ₂ H Examples include methoxydisilane compounds represented by ₄ Si (OC ₂ H ₅ ) ₃ , (H ₅ C ₂ O) ₃ SiC ₂ H ₄ C ₆ F ₁₂ C ₂ H ₄ Si (OC ₂ H ₅ ) ₃ , and the like.

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

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

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

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

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

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

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

  Examples of the polymer used as the other binder of the low refractive index layer include polyvinyl alcohol, polyoxyethylene, polymethyl methacrylate, polymethyl acrylate, fluoroacrylate, diacetyl cellulose, triacetyl cellulose, nitrocellulose, polyester, and alkyd resin. Can be mentioned.

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

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

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

(High refractive index layer)
In the present invention, the antireflective layer preferably has the following high refractive index layer in addition to the above-described low refractive index layer, and the high refractive index layer contains the ionic liquid according to the present invention. Is preferred.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

General formula (CL1) _An MB _xn
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 above formula (2) includes an alkoxide having two or more alkoxyl groups bonded directly to a metal atom, or a chelate compound thereof. Preferable metal compounds include titanium alkoxide, zirconium alkoxide, or chelate compounds thereof. Titanium alkoxide has a high reaction rate and a high refractive index and is easy to handle. However, since it has a photocatalytic action, its light resistance deteriorates when added in a large amount. Zirconium alkoxide has a high refractive index but tends to become cloudy, so care must be taken in dew point management during coating. Moreover, since titanium alkoxide has the effect of promoting the reaction between the ultraviolet curable resin and the metal alkoxide, the physical properties of the coating film can be improved even by adding a small amount.

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

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

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

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

  The high refractive index layer according to the present invention can contain an ionizing radiation curable resin as a binder for the metal oxide fine particles in order to improve the film formability and physical properties of the coating film. As the ionizing radiation curable resin, a monomer or oligomer having two or more functional groups that cause polymerization reaction directly by irradiation of ionizing radiation such as ultraviolet rays or electron beams or indirectly by the action of a photopolymerization initiator is used. Can be used. 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 an ionizing 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, tetramethylol methane 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, glycerol 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.

  The addition amount of the ionizing 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 ionizing radiation curable resin according to the present invention, the photopolymerization initiator and the acrylic compound having two or more polymerizable unsaturated bonds in the molecule are in a mass ratio of 3: 7 to 1: 9. It is preferable to contain.

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

  Examples of the organic solvent used for coating the high refractive index layer according to the present invention include alcohols (for example, methanol, ethanol, propanol, isopropanol, butanol, isobutanol, secondary butanol, tertiary butanol, pentanol, Hexanol, cyclohexanol, benzyl alcohol, etc.), polyhydric alcohols (for example, ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, polypropylene glycol, butylene glycol, hexanediol, pentanediol, glycerin, Hexanetriol, thiodiglycol, etc.), polyhydric alcohol ethers (eg, 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 (eg, ethanolamine, diethanolamine, triethanolamine, N-methyldiethanolamine, N-ethyldiethanolamine, morpholine, N-ethylmolybdenum) Holin, ethylenediamine, diethylenediamine, triethylenetetramine, tetraethylenepentamine, polyethyleneimine, pentamethyldiethylenetriamine, tetramethylpropylenediamine, etc.), amides (eg, formamide, N, N-dimethylformamide, N, N-dimethylacetamide) Etc.), heterocyclic rings (for example, 2-pyrrolidone, N-methyl-2-pyrrolidone, cyclohexyl pyrrolidone, 2-oxazolidone, 1,3-dimethyl-2-imidazolidinone, etc.), sulfoxides (for example, dimethyl sulfoxide, etc.) ), Sulfones (for example, sulfolane, etc.), urea, acetonitrile, acetone and the like, and alcohols, polyhydric alcohols, and polyhydric alcohol ethers are particularly preferable.

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

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

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

  Among these, Aerosil 200V and Aerosil R972V are particularly preferably used because they have a large anti-blocking effect while keeping haze low. 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 fine 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.

  These coating compositions are preferably applied to the surface of the transparent resin 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. Is particularly preferably 5 to 30 μm. Examples of the resin used as the binder of the backcoat layer include vinyl chloride-vinyl acetate copolymer, vinyl chloride resin, vinyl acetate resin, vinyl acetate-vinyl alcohol copolymer, partially hydrolyzed vinyl chloride-vinyl acetate copolymer. Polymer, vinyl chloride-vinylidene chloride copolymer, vinyl chloride-acrylonitrile copolymer, ethylene-vinyl alcohol copolymer, chlorinated polyvinyl chloride, ethylene-vinyl chloride copolymer, ethylene-vinyl acetate copolymer, etc. Vinyl polymer or copolymer, nitrocellulose, cellulose acetate propionate (preferably acetyl group substitution degree 1.8-2.3, propionyl group substitution degree 0.1-1.0), diacetyl cellulose, cellulose Cellulose derivatives such as acetate butyrate resin, maleic acid and / or Or acrylic acid copolymer, acrylic ester copolymer, acrylonitrile-styrene copolymer, chlorinated polyethylene, acrylonitrile-chlorinated polyethylene-styrene copolymer, methyl methacrylate-butadiene-styrene copolymer, acrylic resin , Polyvinyl alcohol resin, polyvinyl acetal resin, polyvinyl butyral resin, urethane resin, polyester polyurethane resin, polyether polyurethane resin, polycarbonate polyurethane resin, polyester resin, polyether resin, polyamide resin, amino resin, styrene-butadiene resin, butadiene-acrylonitrile Examples thereof include, but are not limited to, rubber resins such as resins, silicone resins, fluorine resins, and the like. For example, as an acrylic resin, Acrypet MD, VH, MF, V (manufactured by Mitsubishi Rayon Co., Ltd.), Hyperl M-4003, M-4005, M-4006, M-4202, M-5000, M-5001, M-4501 (manufactured by Negami Kogyo Co., Ltd.), Dialnal BR-50, BR-52, BR-53, BR-60, BR-64, BR-73, BR-75, BR-77, BR-79, BR -80, BR-82, BR-83, BR-85, BR-87, BR-88, BR-90, BR-93, BR-95, BR-100, BR-101, BR-102, BR-105 BR-106, BR-107, BR-108, BR-112, BR-113, BR-115, BR-116, BR-117, BR-118, etc. (Mitsubishi Rayon Co., Ltd.) acrylic and The methacrylic monomers are commercially available various homopolymers and copolymers, etc. was prepared as a raw material, it is also possible to select a preferred mono from this appropriate. For example, as a resin used as a binder, it is preferable to use a blend of cellulose ester such as cellulose diacetate and cellulose acetate prothionate and an acrylic resin, and the refractive index of the fine particles and the binder using fine particles made of an acrylic resin. By setting the difference to be less than 0 to 0.02, a highly transparent back coat layer can be obtained.

  The order of coating the backcoat layer may be before or after coating the active energy ray curable resin layer of the antireflection film of the present invention, but when the backcoat layer also serves as an antiblocking layer, it is coated first. It is desirable. Alternatively, the backcoat layer can be applied in two or more steps. Moreover, it is also preferable that the backcoat layer also serves as an easy-adhesion layer for improving the adhesion with the polarizer.

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

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

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

  In the present invention, the surface treatment is preferably performed before each layer is applied. 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 more between the electrodes under atmospheric pressure and discharging it. An apparatus commercially available from Kasuga Electric Co., Ltd. or Toyo Electric Co., Ltd. Can be used. 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 aluminum, stainless steel, or a metal thereof, and a roll lined with ceramic, silicon, EPT rubber, hyperon rubber, or the like. 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 is difficult to perform stable processing, resulting in uneven processing. Will occur. 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.

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

  Furthermore, the antireflection film of the present invention is produced by a production method in which the hard coat layer and the antireflection layer are laminated on a transparent resin film, and then heat-treated at 50 to 160 ° C. while being wound up in a roll shape. It is preferable. The period of the heat treatment may be appropriately determined depending on the set temperature. For example, if it is 50 ° C., it preferably ranges from 3 days to less than 30 days, and if it is 160 ° C., it ranges from 10 minutes to 1 day. preferable. Usually, it is preferably set at a relatively low temperature so that the heat treatment effect at the outside of the winding, the center of the winding, and the core is not biased, and is preferably performed at around 50 to 60 ° C. for about 7 days.

  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 without dust.

  When winding the antireflection film coated with the functional thin film into a roll, the winding core is not particularly limited as long as it is a cylindrical core, but is preferably a hollow plastic core, and the plastic material is heated. A heat-resistant plastic that can withstand the processing temperature is preferable, and examples thereof include resins such as phenol resin, xylene resin, melamine resin, polyester resin, and epoxy resin. 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.

  In this way, when the heat treatment is performed in a state where the functional thin film is coated on the long plastic film substrate and the roll wound around the plastic core is wound, it is preferable to rotate the roll. The rotation is preferably performed at a speed of 1 rotation or less per minute, and may be continuous or intermittent. Moreover, it is preferable to perform rewinding of the roll once or more during the heating period.

  In order to rotate the long antireflection film roll wound around the core during the heat treatment, it is preferable to provide a dedicated turntable in the heat treatment chamber.

  In the case of intermittent rotation, the stop time is preferably within 10 hours, the stop position is preferably made uniform in the circumferential direction, and the stop time is within 10 minutes. More preferred. Most preferred is continuous rotation.

  As for the rotation speed in continuous rotation, the time required for one rotation is preferably 10 hours or less, and if it is early, it becomes a burden on the apparatus, so the range of 15 minutes to 2 hours is substantially preferable.

  In the case of a dedicated carriage having a rotation function, it is preferable that the antireflection film roll can be rotated during movement and storage. In this case, rotation is effective as a countermeasure against black bands that occur when the storage period is long. To work.

<Transparent resin film>
The transparent resin film used for this invention is demonstrated.

  The transparent resin film used in the present invention is easy to manufacture, has good adhesion to the actinic radiation curable resin layer, is optically isotropic, is optically transparent, etc. Is mentioned as a preferable requirement.

  The term “transparent” as used in the present invention 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-type films, such as a cellulose diacetate film, a cellulose triacetate film, a cellulose acetate propionate film, a cellulose acetate butyrate film, a polyester-type 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, polyetherketone film, polyetherketoneimide film, polyamide film, fluororesin film, nylon film, A polymethyl methacrylate film, an acrylic film, a glass plate, etc. can be mentioned. Among these, a cellulose ester film, a polycarbonate film, a polysulfone (including polyether sulfone) film, and a cycloolefin polymer film are preferable. In the present invention, in particular, a cellulose ester film (for example, Konica Minoltack, product name KC8UX, KC4UX, KC5UX, KC8UCR3, KC8UCR4, KC8UCR5, KC8UY, KC4UY, KC4UE, KC12UR (above, manufactured by Konica Minolta Opto Co., Ltd.) are preferably used from the viewpoints of cost, transparency, adhesiveness and the like. These films may be films produced by melt casting film formation or films produced by solution casting film formation.

  In the present invention, it is preferable to use a cellulose ester film (hereinafter also referred to as a cellulose ester film) as the transparent resin 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 acetyl group is X and the substitution degree of propionyl group or butyryl group is Y, hard coat layer and antireflection on transparent resin film having mixed fatty acid ester of cellulose where X and Y are in the following range An antireflection film provided with a layer is preferred.

2.3 ≦ X + Y ≦ 3.0
0.1 ≦ Y ≦ 2.0
In particular, 2.5 ≦ X + Y ≦ 2.9
It is preferable that 0.3 ≦ Y ≦ 1.2.

  The transparent resin film of the present invention is a transparent resin having a free volume radius of 0.250 to 0.310 nm required by the positron annihilation lifetime method in order to obtain an antireflection film having little flatness due to heat treatment and excellent flatness. A resin film is preferred. Furthermore, a transparent resin film having a total free volume parameter of 1.0 to 2.0 is more preferable. A cellulose ester film is particularly preferable.

  The free volume in this invention represents the space | gap part which is not occupied by the cellulose-ester molecular chain. 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 You can ask.

<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 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
In accordance with the above measurement conditions, positron annihilation lifetime measurement is performed, and three-component analysis is performed by the nonlinear least square method, and τ1, τ2, and τ3 are set from the ones with the smallest annihilation lifetime, and the corresponding intensities are I ₁ , I ₂ , 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. τ3 corresponds to positron annihilation in the vacancies, and it is considered that the larger the τ3, the larger the vacancy size.

τ3 = (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.

  Further, the total free volume parameter VP was obtained by the following equation.

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

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

  The positron annihilation lifetime method is described in, 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” can be referred to. .

  The free volume radius of the cellulose ester film used in the present invention 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. It may be industrially difficult to produce a cellulose ester film having a free volume radius of less than 0.250 nm or a total free volume parameter of less than 1.0. 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. Moreover, the preferable range of a total free volume parameter is 1.0-2.0, and a more preferable range is 1.2-1.8. If the total free volume parameter is less than 1.8, the stability to heat treatment is further increased, which is preferable. Moreover, it is preferable that the half value width of a free volume radius is 0.04-0.1 nm.

  The method for setting the free volume radius and the total free volume parameter of the cellulose ester film containing at least a plasticizer and a cellulose ester within a predetermined range is not particularly limited, but these can be controlled by the following method.

  The cellulose ester film having a free volume radius determined by the positron annihilation lifetime method of 0.250 to 0.315 nm, preferably 0.250 to 0.310 nm, and a total free volume parameter of 1.0 to 2.0 is at least a plasticizer. And a dope containing cellulose ester is cast to produce a web, stretched in a state containing a solvent, and then dried until the residual solvent amount is less than 0.3% to obtain a cellulose ester film. This is further processed at 105 to 155 ° C. in an atmosphere with an atmosphere substitution rate of 12 times / hour or more, preferably 12 to 45 times / hour, so that the predetermined free volume radius and total free volume parameters can be obtained. A certain cellulose ester film can be obtained.

The atmosphere replacement rate is defined as follows. When the atmosphere capacity of the heat treatment chamber is V (m ³ ) and the fresh air flow rate is FA (m ³ / hr), the atmosphere of the heat treatment chamber per unit time determined by the following formula is Fresh-air. Is the number of replacements by. “Fresh-air” means that the air blown into the heat treatment chamber is not a wind that is recirculated and does not contain a volatilized solvent or plasticizer or a fresh air from which they are removed. Yes.

Atmosphere replacement rate = FA / V (times / hour)
When the processing temperature exceeds 155 ° C., flatness is liable to be lowered, so that careful attention is required for conveyance. Furthermore, it is preferably used as the transparent resin film used in the present invention by being treated in an atmosphere maintained at an atmosphere substitution rate of 12 times / hour or more in the treatment section.

  This is because the atmosphere substitution rate of 12 times / hour or more can sufficiently reduce the plasticizer concentration in the atmosphere by the plasticizer volatilized from the cellulose ester film, and reattachment to the film is reduced. It is presumed that this contributes to obtaining the effects of the present invention by using the transparent resin film thus produced. In a normal drying process, the atmosphere substitution rate is 10 times / hour or less. If the substitution rate is increased more than necessary, the cost increases, which is not preferable. Also, since the web tends to flutter due to flapping, it is not preferable to increase it particularly when producing a cellulose ester film. Once the drying is completed and the residual solvent amount is reduced, the atmosphere substitution rate can be increased. However, if it exceeds 45 times, the cost of the air conditioner will increase extremely, which is not practical. The treatment time under these conditions is preferably 1 minute to 1 hour. If it is less than 1 minute, it is difficult to make a free volume radius into a predetermined range, and it is preferable that it is 1 hour or less in order to acquire the effect by this process.

  Further, in this treatment step, pressure treatment in the thickness direction can also control the free volume radius and the total free volume parameter within a more preferable range. A preferable pressure is 0.5 to 10 kPa. The amount of residual solvent when applying pressure is desirably less than 0.3%.

  The conventional cellulose ester film not subjected to such treatment has a free volume radius exceeding 0.315.

  The cellulose as a raw material for the cellulose ester used in the present invention is not particularly limited, and examples thereof include cotton linters, wood pulp (derived from coniferous trees, derived from broadleaf trees), 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).

  Cellulose ester used in the present invention As described above, a mixture of cellulose having propionate group or butyrate group in addition to acetyl group such as cellulose acetate propionate, cellulose acetate butyrate, or cellulose acetate propionate butyrate Fatty acid esters are particularly preferably used. The butyryl group that forms butyrate may be linear or branched.

  Cellulose acetate propionate containing a propionate group as a substituent has excellent water resistance and is useful as a film for liquid crystal image display devices.

  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.

  The cellulose ester film preferred as the transparent resin of the present invention is a casting of an endless metal belt or a rotating metal drum that transfers a cellulose ester solution (dope) generally called a solution casting method, for example, infinitely. The dope is cast (casted) from a pressure die on a support for manufacturing, and is produced by a method of 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 good solvents described above, methylene chloride or methyl acetate, which is excellent in 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 dope described above onto a 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. It is also used as a gelling solvent for facilitating the dissolution, and when these ratios are 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.

  When a cellulose ester film is used for the antireflection film of the present invention, it is preferable to contain 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 comprising an ester of a dihydric 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 (6).

Formula (6) R ₁ — (OH) _n
However, R ₁ represents an n-valent organic group, n represents a positive integer of 2 or more, and the 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, and xylitol. 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 the polyhydric alcohol ester of this invention, 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 thereto.

  As the aliphatic monocarboxylic acid, a fatty acid having a straight chain or a 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 preferable alicyclic monocarboxylic acids include cyclopentanecarboxylic acid, cyclohexanecarboxylic acid, cyclooctanecarboxylic acid, and 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 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>
The cellulose ester film used in the present invention preferably contains an acrylic polymer having a negative average birefringence in the stretching direction and having a weight average molecular weight of 500 or more and 30000 or less, and the acrylic polymer has an aromatic ring side. An acrylic polymer having a chain or an acrylic polymer having a cyclohexyl group in a side chain is preferred.

  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 too much.

  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 of using a chain transfer agent such as carbon tetrachloride, a method of using a polymerization terminator such as benzoquinone and dinitrobenzene in addition to the polymerization initiator, and further, Japanese Patent Application Laid-Open No. 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. Although used, the method described in the publication is particularly preferable.

  Although the monomer as a monomer unit which comprises the polymer useful for this invention is mentioned below, it is not limited to this.

  The ethylenically unsaturated monomer unit constituting the polymer obtained by polymerizing the ethylenically unsaturated monomer is as a vinyl ester, for example, vinyl acetate, vinyl propionate, vinyl butyrate, vinyl valerate, vinyl pivalate, caproic acid. Vinyl, vinyl caprate, vinyl laurate, vinyl myristate, vinyl palmitate, vinyl stearate, vinyl cyclohexanecarboxylate, vinyl octylate, vinyl methacrylate, vinyl crotonate, vinyl sorbate, vinyl benzoate, vinyl cinnamate Etc .; As acrylate ester, 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 Cyclohexyl acid, acrylic acid (2-ethylhexyl), benzyl acrylate, phenethyl acrylate, 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-p-hydroxymethylphenyl, acrylic acid-p- (2-hydroxyethyl) phenyl, etc .; The above acrylic acid ester is changed to methacrylic acid ester; Examples thereof include acrylic acid, methacrylic acid, maleic anhydride, crotonic acid, itaconic acid and the like. The polymer composed of the above monomers may be a copolymer or a homopolymer, and is preferably a vinyl ester homopolymer, a vinyl ester copolymer, or a copolymer of vinyl ester and acrylic acid or methacrylic acid ester.

  In the present invention, an acrylic polymer (simply referred to as an acrylic polymer) refers to a homopolymer or 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.

  A polymer obtained by polymerizing the above ethylenically unsaturated monomer, an acrylic polymer, an acrylic polymer having an aromatic ring in the side chain, and an acrylic polymer 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.

  In the present invention, 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. A compound having one thiol group and a secondary hydroxyl group as described in JP-A No. 2000-128911 or 2000-344823, or a polymerization catalyst using the compound and an organometallic compound in combination The method described in the above publication is particularly preferred.

  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. In the present invention, 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 preferred 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.

  Further, the cellulose ester film used in the present invention is composed of an ethylenically unsaturated monomer Xa having no aromatic ring and a hydrophilic group in the molecule and an ethylenically unsaturated group having no hydrophilic ring and having a hydrophilic group in the molecule. A weight average molecular weight of 500 or more obtained by polymerizing a polymer X having a weight average molecular weight of 5000 or more and 30000 or less obtained by copolymerization with the monomer Xb, and more preferably an ethylenically unsaturated monomer Ya having no aromatic ring. It is preferable to contain 3000 or less polymer Y.

(Polymer X, Polymer Y)
The polymer X used in the present invention comprises 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 and having a hydrophilic group in the molecule. It is a polymer having a weight average molecular weight of 5,000 to 30,000 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 used in the present invention is represented by the following general formula (X).

Formula (X)
-(Xa) m- (Xb) n- (Xc) p-
More preferably, it is a polymer represented by the following general formula (X-1).

Formula (X-1)
_{- [CH 2 -C (-R1)} (- CO 2 R2)] m- [CH 2 -C (-R3) (- CO 2 R4-OH) -] n- [Xc] p-
(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 or a cycloalkyl group. R ₄ represents —CH ₂ —, —C ₂ H ₄ — or —C _3. H ₆ -. .Xc representing a is Xa, .m representing a monomer unit polymerizable with Xb, n and p each indicate a molar ratio, however m ≠ 0, n ≠ 0, k ≠ 0, m + n + p = 100 .)
Although the monomer as a monomer unit which comprises the polymer X used for this invention is mentioned below, it is not limited to this.

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

  Examples of the ethylenically unsaturated monomer Xa having no aromatic ring and no hydrophilic group in the molecule include methyl acrylate, ethyl acrylate, propyl acrylate (i-, n-), and 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-ethoxyethyl) ) Or the like, or those obtained by replacing the acrylic ester with a methacrylic ester. 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), List acrylic acid (2-hydroxypropyl), acrylic acid (3-hydroxypropyl), acrylic acid (4-hydroxybutyl), acrylic acid (2-hydroxybutyl), or those in which these acrylic acids are replaced by methacrylic acid. Acrylic acid (2-hydroxyethyl) and methacrylic acid (2-hydroxyethyl), acrylic acid (2-hydroxypropyl), and acrylic acid (3-hydroxypropyl) are preferable.

  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 m: n of Xa, Xb and Xc is preferably in the range of 99: 1 to 65:35, 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, the compatibility with the cellulose ester is improved, but the retardation value Rt in the film thickness direction is increased. When the molar composition ratio of Xb is large, the compatibility is deteriorated, but the effect of reducing Rt is high. Further, if the molar composition ratio of Xb exceeds the above range, haze tends to occur during film formation, and 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, 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 used in the present invention 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 room temperature to 130 ° C., preferably 50 ° C. to 100 ° C., and this temperature or the polymerization reaction time can be adjusted.

  The measuring method of a weight average molecular weight can be based on the following method.

(Weight average molecular weight measurement method)
The weight average molecular weight Mw was 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 Corp.) Mw = 100000-500 calibration curves with 13 samples were used. Thirteen samples are used at approximately equal intervals.

  The polymer Y used in the present invention 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.

  A weight average molecular weight of 500 or more is preferable because the residual monomer of the polymer is reduced. Moreover, it is preferable to set it as 3000 or less in order to maintain retardation value Rt fall performance.

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

  The polymer Y used in the present invention is represented by the following general formula (Y).

General formula (Y)
-(Ya) k- (Yb) q-
More preferably, it is a polymer represented by the following general formula (Y-1).

General formula (Y-1)
_{- [CH 2 -C (-R5)} (- CO 2 R6)] k- [Yb] q-
(Wherein, R5 is, .Yb .R6 representing H or CH ₃ is representing an alkyl group or a cycloalkyl group having 1 to 12 carbon atoms, .k and q represents the Ya and copolymerizable monomer units, This represents the 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, for example, acrylic acid, methacrylic acid And 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 polymers X and 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. 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 of using a chain transfer agent such as carbon tetrachloride, a method of using a polymerization terminator such as benzoquinone and dinitrobenzene in addition to the polymerization initiator, and further, Japanese Patent Application Laid-Open No. 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, a polymerization method using a compound having a thiol group and a secondary hydroxyl group in the molecule as a chain transfer agent. It is preferred.

  In this case, the terminal of the polymer X and 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 polymers X and Y and the cellulose ester can be adjusted.

  The hydroxyl values of the polymers X and Y are preferably 30 to 150 [mg KOH / g].

(Measurement method of hydroxyl value)
This measurement conforms to JIS K 0070 (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, 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
(Wherein B is the amount of 0.5 mol / L potassium hydroxide ethanol solution used in the blank test (ml), and C is the amount of 0.5 mol / L potassium hydroxide ethanol solution used in the titration (ml). F is a factor of 0.5 mol / L potassium hydroxide ethanol solution, D is an acid value, and 28.05 is 1/2 of 1 mol amount of potassium hydroxide 56.11)
The above-mentioned polymer X and polymer Y are both excellent in compatibility with cellulose ester, excellent in productivity without evaporation and volatilization, good retention as a protective film for polarizing plates, low moisture permeability, and dimensional stability. Are better.

The content of the polymer X and the polymer Y in the cellulose ester film is preferably in a 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.

  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 retardation value Rt. 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 liquid described later, or can be added to the dope liquid 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 amount is too small, deterioration of flatness is recognized, and if it is too large, bleeding out tends to occur. The mass ratio between the polyhydric alcohol ester plasticizer and the other plasticizer is preferably in the range of 1: 4 to 4: 1, 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, which is not preferable.

  An ultraviolet absorber is preferably used for the antireflection film of the present invention.

  As the ultraviolet absorber, those excellent in the ability to absorb ultraviolet rays having a wavelength of 370 nm or less and having little 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 ultraviolet absorbers preferably used in the present invention include, for example, oxybenzophenone compounds, benzotriazole compounds, salicylic acid ester compounds, benzophenone compounds, cyanoacrylate compounds, triazine compounds, nickel complex compounds, and the like. However, it is not limited to these.

  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- 4-Hydroxy-5- (5-chloro-2H-benzotriazol-2-yl) phenyl] propionate (TINUVIN109, 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 ultraviolet absorber preferably used in the present invention, a benzotriazole-based ultraviolet absorber and a benzophenone-based ultraviolet absorber that are highly transparent and excellent in preventing the deterioration of the polarizing plate and the liquid crystal are preferable, and unnecessary coloring is less. A benzotriazole-based ultraviolet absorber is particularly preferably used.

  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.

  Further, the polymer ultraviolet absorber described in the general formula (1) or general formula (2) described in JP-A-6-148430 and the general formulas (3), (6), and (7) described in Japanese Patent Application No. 2000-156039 (Or UV-absorbing polymer) is also preferably used. As a polymer ultraviolet absorber, PUVA-30M (manufactured by Otsuka Chemical Co., Ltd.) and the like are commercially available.

  Moreover, in order to provide slipperiness to the cellulose-ester film used for this invention, the microparticles | fine-particles similar to what is described with the application layer containing the above-mentioned actinic radiation curable resin can be used.

  As fine particles, as examples of inorganic compounds, 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. Fine particles containing silicon are preferable in terms of low turbidity, and silicon dioxide is particularly preferable.

  The average primary particle diameter of the fine 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 of these fine particles in the cellulose ester film is preferably 0.05 to 1% by mass, particularly preferably 0.1 to 0.5% by mass. In the case of a cellulose ester film having a multilayer structure by the co-casting method, it is preferable to contain fine particles of this addition amount on the surface.

  Silicon dioxide fine 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.). it can.

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

  Polymer particles can also be used as the fine 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.) It is marketed by name and can be used.

  Among these, Aerosil 200V and Aerosil R972V are particularly preferably used because they have a large effect of reducing the friction coefficient while keeping the turbidity of the cellulose ester film low. In the cellulose ester film used in the present invention, it is preferable that the coefficient of dynamic friction on the side opposite to the side where the hard coat layer is provided is 1.0 or less.

<Method for producing cellulose ester film>
Next, the solution casting method will be described first for the method for producing a cellulose ester film.

(Solution casting method)
Manufacture of the cellulose ester film by the solution casting method is a step of preparing a dope by dissolving the cellulose ester and additives in a solvent, a step of casting the dope on a belt-shaped or drum-shaped metal support, and casting. It is performed by a step of drying the dope as a web, a step of peeling from the metal support, a step of stretching or maintaining the width, a step of drying, and a step of winding the finished film.

  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.

  Although the good solvent used for this invention is not specifically limited, Organic halogen compounds, such as a methylene chloride, dioxolanes, acetone, methyl acetate, methyl acetoacetate, etc. are mentioned. Particularly preferred is methylene chloride or methyl acetate.

  Moreover, although the poor solvent used for this invention is not specifically limited, For example, methanol, ethanol, n-butanol, cyclohexane, cyclohexanone, etc. are used preferably. 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.

  The 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, it is preferable that the absolute filtration accuracy is small in order to remove insoluble matters and the like. 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.

  There are no particular restrictions on the material of the filter medium, and ordinary filter media can be used. However, plastic filter media such as polypropylene and Teflon (registered trademark), and metal filter media such as stainless steel do not drop off fibers. preferable. It is preferable to remove and reduce impurities, particularly bright spot foreign matter, contained in the raw material cellulose ester by filtration.

A bright spot foreign substance is when two polarizing plates are placed in a crossed Nicol state, a cellulose ester film is placed between them, light is applied from the side of one polarizing plate, and observed from the side of the other polarizing plate. It is a point (foreign matter) where light from the opposite side appears to leak, and the number of bright spots having a diameter of 0.01 mm or more is preferably 200 / 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.

  Here, the dope casting will be described.

  The metal support in the casting (casting) step preferably has a mirror-finished surface, and a stainless steel belt or a drum whose surface is plated with a casting is preferably used as the metal support. 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. A higher temperature is preferred because the web can be dried faster, but if it is too high, the web may foam or the 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 warm 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, there may be cases where wind at a temperature higher than the target temperature is used while preventing foaming. . 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
Note that M is the mass of a sample collected 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 method of drying while transporting the web by a tenter method is adopted.

  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 hard-coat layer of a cellulose-ester film can use a 0.001-1 micrometer thing.

(Melt casting method)
The cellulose ester film used for the antireflection film according to the present invention is also preferably formed by a melt casting method.

  The molding method by melt casting that heats and melts without using the solvent (for example, methylene chloride, etc.) used in the solution casting method, more specifically, melt extrusion molding method, press molding method, inflation method, injection molding method And can be classified into blow molding, stretch molding 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.

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

  In the present invention, the cellulose ester and other additives such as a stabilizer added if necessary are preferably mixed before melting, and more preferably the cellulose ester and the additive are 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, or a ribbon mixer 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 necessary, but 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 it is Tg or more with respect to the glass transition temperature Tg of the film. Tg + 100 ° C. or lower, preferably Tg + 10 ° C. or higher, and Tg + 90 ° C. or lower. 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, 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 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 described above is heated in a range of Tg + 100 ° C. from the glass transition temperature (Tg) of the cellulose ester via a heating device such as a plurality of roll groups and / or an infrared heater, 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.

  It is preferable to perform heat processing, conveying normally for 0.5 to 300 second within the range of Tg-20 degreeC-extending | stretching temperature.

  The heat-treated film is usually cooled to Tg or less, 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 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. In particular, it is preferable to perform these treatments while sequentially cooling in a plurality of temperature ranges from the viewpoint of improving the dimensional stability of the film. The cooling rate is a value obtained by (T1-Tg) / t, where T1 is the final heat treatment temperature and t is the time until the film reaches Tg from the final heat treatment temperature.

  The additive preferably used when manufacturing a transparent resin film by the melt casting method 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 resin film used in the present invention is formed at a high temperature of 200 ° C. or higher. It is preferable to contain in.

  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, for the purpose of the present invention, it is preferable to include an antioxidant as a deterioration preventing agent in the film forming material.

  The deterioration preventing agent in the film-forming material used in the present invention can be selected from at least one or more. The amount to be added is 0.01% with respect to the mass of the cellulose ester used in the present invention. The mass is preferably from 10% by mass to 10% by mass, more preferably from 0.1% by mass to 5.0% by mass, and still more preferably from 0.2% by mass to 2.0% by mass.

  In addition, it is preferable that the addition amount of the deterioration inhibitor is larger than the above range of the addition amount because it causes a decrease in transparency as a transparent resin film from the viewpoint of compatibility with the cellulose ester, and the film may become brittle. Absent.

  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.

  When the film-forming material is heat-melted, and when the heat-melted material is used in a post-process, or when used as a product under the consumer, the presence of the above-mentioned deterioration preventive agent It is excellent in terms of reducing the strength and deterioration of optical transparency due to deterioration and decomposition, or maintaining the strength inherent to the material.

  If the film-forming material is significantly deteriorated by heating, coloring may occur and it may not be used as an antireflection film. Moreover, when there exists an extending | stretching process after a casting process, when a film forming material deteriorates remarkably by heating, the formed film will become weak and it will become easy to produce a fracture | rupture in an extending process.

  Therefore, the presence of the above-mentioned deterioration preventing agent suppresses the generation of a colored material in the visible light region at the time of heating and melting, or a volatile component generated by decomposition of the material constituting the film at the time of heating and melting. It is also excellent in that it can suppress or eliminate deterioration that is undesirable as an antireflection film such as a decrease in transmittance and haze value caused by the above.

  In the present invention, the display image of the liquid crystal display device is affected when the haze value of the film exceeds 1%. Therefore, the haze value is preferably less than 1%, more preferably less than 0.5%. As an index of colorability, yellowness (yellow index, YI) can be used, preferably 3.0 or less, more preferably 1.0 or less. Yellowness can be measured based on JIS-K7103.

  In the above-described film forming material storage or film forming process, deterioration reactions due to oxygen or moisture in the air may occur simultaneously. In this case, in addition to the stabilizing action of the deterioration preventing agent, reducing the humidity and oxygen concentration in the air can be preferably used in combination for realizing the present invention. This includes the use of nitrogen or argon as an inert gas as a known technique, degassing operation under reduced pressure to vacuum, and operation in a sealed environment, and at least one of these three methods is the presence of the stabilizer. It is preferable to use together.

<Antioxidant>
Since cellulose ester is decomposed not only by heat but also by oxygen at a high temperature, the antireflection film of the present invention preferably contains an antioxidant as a deterioration preventing agent.

  The antioxidant useful in the present invention can be used without limitation as long as it is a compound that suppresses deterioration of the film-forming material due to oxygen, and among them, a phenolic antioxidant, a phosphorus antioxidant, and a sulfur antioxidant. Agents, alkyl radical scavengers, 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 agents, a phosphorus-based antioxidant and an alkyl radical scavenger. By blending these antioxidants, it is possible to prevent coloring and 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 the 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 No. 839,405, and 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 useful in the present invention 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, from Sumitomo Chemical Co., Ltd., “Sumizer GP”, from Asahi Denka Kogyo Co., Ltd., “ADK STAB PEP-24G”, “ADK STAB PEP-36”, “ADK STAB 3010”, “ It is commercially available under the trade 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 from Ciba Specialty Chemicals Co., Ltd. under the trade name “IRGAFOS P-EPQ” and from Sakai Chemical Industry Co., Ltd. as “GSY-P101”.

  As the phosphorus antioxidant useful in the present invention, a phosphonite compound is preferable, and among them, 4,4 ′ such as tetrakis (2,4-di-t-butyl-phenyl) -4,4′-biphenylenediphosphonite. -Biphenylene diphosphonite compounds are preferred, and tetrakis (2,4-di-t-butyl-5-methylphenyl) -4,4'-biphenylene diphosphonite is particularly preferred.

(Alkyl radical scavenger)
In the present invention, the “alkyl radical scavenger” means a compound having a group that can react rapidly with an alkyl radical and giving a stable product that does not undergo subsequent reaction after reaction with the alkyl radical.

  Preferred alkyl radical scavengers in the present invention include a compound represented by the following general formula (7) and a compound represented by the following general formula (8).

[Wherein, R ₁ represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and R ₂ and R ₃ each independently represents an alkyl group having 1 to 8 carbon atoms. ]

[Wherein, R _{12 to} R ₁₅ each independently represent a hydrogen atom or a substituent, R ₁₆ represents a hydrogen atom or a substituent, and n represents an integer of 1 to 4. When n is 1, R ₁₁ represents a substituent, and when n is an integer of 2 to 4, R ₁₁ represents a divalent to tetravalent linking group. ]
Hereinafter, although the compound represented with the said General formula (7) used for this invention is demonstrated to a specific example, this invention is not limited to these.

In the general formula (7), R ₁ represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, particularly preferably a hydrogen atom or a methyl group. is there.

R ₂ and R ₃ each independently represents an alkyl group having 1 to 8 carbon atoms, and may be linear or have a branched structure or a ring structure. R ₂ and R ₃ are preferably a structure represented by “* —C (CH ₃ ) ₂ —R ′” containing a quaternary carbon (* represents a linking site to an aromatic ring, and R ′ represents a carbon number of 1 Represents an alkyl group of ˜5). R ₂ is more preferably a tert-butyl group, a tert-amyl group or a tert-octyl group. R ₃ is more preferably a tert-butyl group or a tert-amyl group.

  The compound represented by the general formula (7) is commercially available from Sumitomo Chemical Co., Ltd. under the trade names of “Sumilizer GM” and “Sumilizer GS”.

  Although the specific example of a compound represented by the said General formula (7) below is illustrated, this invention is not limited to these.

  Next, although the compound represented by the said General formula (8) used for this invention is demonstrated to a specific example, this invention is not limited to these.

In General formula (8), R < ₁₂ > -R < ₁₅ > represents a hydrogen atom or a substituent each independently. R ₁₂ and R ₁₃ , R ₁₃ and R ₁₄ , or R ₁₄ and R ₁₅ may be bonded to each other to form a ring. R ₁₆ represents a hydrogen atom or a substituent, n represents an integer of 1 to 4, and when n is 1, R ₁₁ represents a substituent, and when n is an integer of 2 to 4, R ₁₁ is Represents a divalent to tetravalent linking group.

When R _{12 to} R ₁₅ represent a substituent, the substituent is not particularly limited. For example, an alkyl group (for example, a methyl group, an ethyl group, a propyl group, an isopropyl group, a t-butyl group, a pentyl group, Hexyl group, octyl group, dodecyl group, trifluoromethyl group, etc.), cycloalkyl group (eg, cyclopentyl group, cyclohexyl group, etc.), aryl group (eg, phenyl group, naphthyl group, etc.), acylamino group (eg, acetylamino) Group, benzoylamino group, etc.), alkylthio group (eg, methylthio group, ethylthio group, etc.), arylthio group (eg, phenylthio group, naphthylthio group, etc.), alkenyl group (eg, vinyl group, 2-propenyl group, 3-butenyl) Group, 1-methyl-3-propenyl group, 3-pentenyl group, 1-methyl-3-butenyl group, 4-hexenyl group, cyclohexenyl group, etc.), halogen atom (eg, fluorine atom, chlorine atom, bromine atom, iodine atom, etc.), alkynyl group (eg, propargyl group, etc.), heterocyclic group (eg, pyridyl group, thiazolyl, etc.) Group, oxazolyl group, imidazolyl group, etc.), alkylsulfonyl group (eg, methylsulfonyl group, ethylsulfonyl group etc.), arylsulfonyl group (eg, phenylsulfonyl group, naphthylsulfonyl group etc.), alkylsulfinyl group (eg, methylsulfinyl group) Group), arylsulfinyl group (for example, phenylsulfinyl group), phosphono group, acyl group (for example, acetyl group, pivaloyl group, benzoyl group), carbamoyl group (for example, aminocarbonyl group, methylaminocarbonyl group, dimethyl group) Aminocarbo Group, butylaminocarbonyl group, cyclohexylaminocarbonyl group, phenylaminocarbonyl group, 2-pyridylaminocarbonyl group, etc.), sulfamoyl group (for example, aminosulfonyl group, methylaminosulfonyl group, dimethylaminosulfonyl group, butylaminosulfonyl group, Hexylaminosulfonyl group, cyclohexylaminosulfonyl group, octylaminosulfonyl group, dodecylaminosulfonyl group, phenylaminosulfonyl group, naphthylaminosulfonyl group, 2-pyridylaminosulfonyl group, etc.), sulfonamide group (for example, methanesulfonamide group, benzene) Sulfonamide group etc.), cyano group, alkoxy group (eg methoxy group, ethoxy group, propoxy group etc.), aryloxy group (eg phenoxy group, naphtho group) Oxy group), heterocyclic oxy group, siloxy group, acyloxy group (for example, acetyloxy group, benzoyloxy group, etc.), sulfonic acid group, sulfonic acid salt, aminocarbonyloxy group, amino group (for example, amino group, Ethylamino group, dimethylamino group, butylamino group, cyclopentylamino group, 2-ethylhexylamino group, dodecylamino group, etc.), anilino group (for example, phenylamino group, chlorophenylamino group, toluidino group, anisidino group, naphthylamino group) 2-pyridylamino group, etc.), imide group, ureido group (for example, methylureido group, ethylureido group, pentylureido group, cyclohexylureido group, octylureido group, dodecylureido group, phenylureido group, naphthylureido group, 2- Pyridylaminoure Id group etc.), alkoxycarbonylamino group (eg methoxycarbonylamino group, phenoxycarbonylamino group etc.), alkoxycarbonyl group (eg methoxycarbonyl group, ethoxycarbonyl group, phenoxycarbonyl etc.), aryloxycarbonyl group (eg Phenoxycarbonyl group, etc.), heterocyclic thio group, thioureido group, carboxyl group, carboxylic acid salt, hydroxyl group, mercapto group, nitro group and the like. These substituents may be further substituted with the same substituent.

In the general formula (8), R _{12 to} R ₁₅ are preferably a hydrogen atom or an alkyl group.

In the general formula (8), R ₁₆ represents a hydrogen atom or a substituent, and examples of the substituent represented by R ₁₆ include the same groups as the substituents represented by R _{12 to} R ₁₅ . In particular, R ₁₆ is preferably a hydrogen atom.

In the general formula (8), n represents an integer of 1 to 4, but when n is 1, R ₁₁ represents a substituent, and the substituent is the same as the substituent represented by R _{12 to} R _15. Can be mentioned. When n is an integer of 2 to 4, R ₁₁ correspondingly represents a divalent to tetravalent linking group.

When R ₁₁ represents a divalent to tetravalent linking group, examples of the divalent linking group include a divalent alkylene group that may have a substituent, a divalent arylene group that may have a substituent, An oxygen atom, a nitrogen atom, a sulfur atom, or a combination of these linking groups can be exemplified.

  Examples of the trivalent linking group include a trivalent alkylene group which may have a substituent, a trivalent arylene group which may have a substituent, a nitrogen atom, or a combination of these linking groups. Examples of the tetravalent linking group include a tetravalent alkylene group which may have a substituent, a tetravalent arylene group which may have a substituent, or a combination of these linking groups. Can do.

In the general formula (8), n is preferably 1, and R ₁₁ at that time is preferably a substituted or unsubstituted phenyl group. The substituent includes an alkyl group having 1 to 18 carbon atoms, and 1 to 18 carbon atoms. Alkoxy groups having 1 to 8 carbon atoms and alkoxy groups having 1 to 8 carbon atoms are more preferable.

  Specific examples of the compound represented by the general formula (8) in the present invention are shown below, but the present invention is not limited thereto.

(Other antioxidants)
Specific examples of the other antioxidants include dilauryl 3,3-thiodipropionate, dimyristyl 3,3′-thiodipropionate, distearyl 3,3-thiodipropionate, lauryl stearyl 3,3. -Thiodipropionate, pentaerythritol-tetrakis (β-lauryl-thio-propionate), 3,9-bis (2-dodecylthioethyl) -2,4,8,10-tetraoxaspiro [5,5] undecane And sulfur-based antioxidants such as The above-mentioned type of sulfur-based compound is commercially available from Sumitomo Chemical Co., Ltd. under the trade names “Sumilizer TPL-R” and “Sumilizer TP-D”, for example. Furthermore, 3,4-dihydro-2H-1-benzopyran compounds, 3,3′-spirodichroman compounds, 1,1-spiroindane compounds, morpholine, thiomorpholine, thio described in JP-B-08-27508 Examples include morpholine oxide, thiomorpholine dioxide, compounds having a piperazine skeleton in the partial structure, and oxygen scavengers such as dialkoxybenzene compounds described in JP-A-3-174150. These antioxidant partial structures may be part of the polymer or regularly pendant to the polymer.

《Hindered amine light stabilizer》
In the present invention, a hindered amine light stabilizer (HALS) is used as an anti-deterioration agent during heat melting of a film-forming material, and as an anti-deterioration agent against external light exposed as a polarizer protective film after production or light from a backlight of a liquid crystal display. Compounds, which are known compounds, such as columns 5-11 of US Pat. No. 4,619,956 and columns 3-5 of US Pat. No. 4,839,405. 2,2,6,6-tetraalkylpiperidine compounds, or their acid addition salts or complexes of them 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 trade names “TINUVIN 144” and “TINUVIN 770” and “ADK STAB LA-52” from Asahi Denka Kogyo Co., Ltd.

  In the present invention, 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, based on the mass of the cellulose ester used in the present invention. Further, it is preferable to add 0.5 to 2% by mass. Two or more of these may be used in combination.

<Acid scavenger>
Cellulose ester is preferably decomposed by an acid in a high temperature environment where melt film formation is performed, and therefore the antireflection film of the present invention preferably contains an acid scavenger as an anti-degradation agent. Any acid scavenger useful in the present invention can be used without limitation as long as it is a compound that reacts with an acid to inactivate the acid, and is described in U.S. Pat. No. 4,137,201. A compound having an epoxy group is preferred. Epoxy compounds as such acid scavengers are known in the art and are derived by condensation of various polyglycol diglycidyl ethers, particularly about 8 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) And epoxidized vegetable oils and other unsaturated natural oils (sometimes epoxies) that 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.) Natural fatty glycerides or unsaturated fatty acids, which generally contain 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.

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

  In 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>
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.

  In this invention, it is preferable to add a metal deactivator 0.0002-2 mass% with respect to the mass of the cellulose ester used for this invention, Furthermore, it is preferable to add 0.0005-2 mass%. Furthermore, it is preferable to add 0.001-1 mass%. Two or more of these may be used in combination.

<Plasticizer>
In forming the antireflection film by melt casting according to the present invention, it is preferable to add at least one plasticizer in the film forming material.

  Generally, a plasticizer is an additive having an effect of improving brittleness or imparting flexibility by adding it to a polymer. In the present invention, a plasticizer is melted. It can be used as an additive that lowers the temperature or as an additive that lowers the viscosity of the film-forming material at the same temperature. Since it is possible to suppress the degradation of the cellulose ester during the melting process by lowering the melting temperature or lowering the melt viscosity, in the present invention, any material having such an effect can be used as a plasticizer without limitation. Can do. Such a melting point lowering effect / viscosity reduction lowering can be more easily obtained when a plasticizer to be added has a melting point or glass transition temperature lower than the glass transition temperature of the cellulose ester.

  In addition, the addition of a plasticizer may improve the mechanical properties of the cellulose ester film, improve the tear strength, impart water resistance resistance, and reduce moisture permeability. It is more preferable to use as a plasticizer.

  In addition, the plasticizer also has an effect of suppressing degradation in the hot melt process of the cellulose ester by adding as described above, but the effect is due to a physical effect and not due to a chemical effect. In the present invention, it is not classified as a deterioration inhibitor.

  Examples of the plasticizer that satisfies the above-described conditions and is used in the present invention include the above-described phosphate ester plasticizers, polyhydric alcohol ester plasticizers (ethylene glycol ester plasticizers, glycerin ester plasticizers, Diglycerin ester plasticizers), polycarboxylic acid ester plasticizers, carbohydrate ester plasticizers, polymer plasticizers, and the like. Moreover, the above-mentioned acrylic polymer can also be used.

  Of these, polyhydric alcohol ester plasticizers and polycarboxylic acid ester plasticizers are preferred, and polyhydric alcohol ester plasticizers are more preferred. Further, the plasticizer may be a liquid or a solid, and is preferably colorless due to restrictions on the composition. The addition amount may be as long as it does not adversely affect the optical properties and mechanical properties, and the blending amount is appropriately selected within the range not impairing the object of the present invention, and preferably 1 to the mass of the cellulose ester used in the present invention. It is a cellulose-ester film characterized by containing 25 mass%. When the content is less than 1% by mass, the effect of improving the flatness is not recognized, and when the content is more than 25% by mass, bleeding out easily occurs and the temporal stability of the film decreases, which is not preferable. More preferred is a cellulose ester film containing 3 to 20% by mass of a plasticizer, and still more preferred is a cellulose ester film containing 5 to 15% by mass.

  In the melt casting method, an ester plasticizer comprising a polyhydric alcohol and a monovalent carboxylic acid, and an ester plasticizer comprising a polyhydric carboxylic acid and a monohydric alcohol are preferred because of their high affinity with the cellulose ester, An ester plasticizer comprising a polyhydric alcohol and a monovalent carboxylic acid is particularly preferred because it further increases the affinity with the cellulose ester.

  More specifically, examples of the polyhydric alcohol that is a raw material of the ester plasticizer preferably used in the present invention include the following, but the present invention is not limited thereto.

  Adonitol, arabitol, ethylene glycol, glycerin, diglycerin, 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-1,3,5-triol, pinacol, sorbitol, trimethylolpropane, ditrimethylolpropane, trimethylolethane, pentaethysitol, dipentaerythritol, xylene Mention may be made of the toll and the like. In particular, ethylene glycol, glycerin, and trimethylolpropane are preferable.

  Examples of preferred organic acids include acetic acid, propionic acid, butyric acid, isobutyric acid, pivalic acid, acrylic acid, methacrylic acid, cyclohexanecarboxylic acid, benzoic acid, anisic acid, 3,4,5-trimethoxybenzoic acid, toluyl Acid, tert-butylbenzoic acid, naphthoic acid, picolinic acid, etc. are mentioned, but polyhydric alcohol ester is formed by unsaturated carboxylic acid, for example, aromatic carboxylic acid, which is highly effective in reducing moisture permeability of cellulose ester It is preferable.

  One type of organic acid may be used for the polyhydric alcohol ester, or a mixture of two or more types may be used. 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.

  Specific examples of ethylene glycol ester plasticizers that are one of the polyhydric alcohol esters include ethylene glycol alkyl ester plasticizers such as ethylene glycol diacetate and ethylene glycol dibutyrate, and ethylene glycol dicyclopropyl. Examples thereof include ethylene glycol cycloalkyl ester plasticizers such as carboxylate and ethylene glycol dicyclohexylcarboxylate, and ethylene glycol aryl ester plasticizers such as ethylene glycol dibenzoate and ethylene glycol di4-methylbenzoate. These alkylate groups, cycloalkylate groups, and arylate groups may be the same or different, and may be further substituted. Further, it may be a mix of alkylate group, cycloalkylate group and arylate group, and these substituents may be covalently bonded. Further, the ethylene glycol part may be substituted, and the ethylene glycol ester partial structure may be part of the polymer or regularly pendant, and may be an antioxidant, an acid scavenger, an ultraviolet absorber, etc. It may be introduced into a part of the molecular structure of the additive.

  Specific examples of the glycerin ester plasticizer that is one of the polyhydric alcohol esters include glycerol alkyl esters such as triacetin, tributyrin, glycerol diacetate caprylate, glycerol oleate propionate, and glycerol tricyclopropylcarboxylate. Glycerol glycerol esters such as glycerol tricyclohexyl carboxylate, glycerol aryl esters such as glycerol tribenzoate and glycerol 4-methylbenzoate, diglycerol tetraacetylate, diglycerol tetrapropionate, diglycerol acetate tricaprylate, diglycerol Tetralaurate, diglycerin alkyl ester, diglycerin tetracyclobutylcarboxylate, diglycerin tet Diglycerol cycloalkyl esters such as cyclopentyl carboxylate, diglycerin tetrabenzoate, diglycerin aryl ester such as diglycerin 3-methylbenzoate or the like. These alkylate groups, cycloalkylcarboxylate groups, and arylate groups may be the same or different, and may be further substituted. Further, it may be a mixture of alkylate group, cycloalkylcarboxylate group, and arylate group, and these substituents may be bonded by a covalent bond. Furthermore, the glycerin and diglycerin part may be substituted, the partial structure of the glycerin ester and the diglycerin ester may be part of the polymer or regularly pendant, and the antioxidant, acid scavenger, You may introduce | transduce into a part of molecular structure of additives, such as a ultraviolet absorber.

  Specific examples of other polyhydric alcohol ester plasticizers include polyhydric alcohol ester plasticizers described in paragraphs 30 to 33 of JP-A No. 2003-12823.

  These alkylate groups, cycloalkylcarboxylate groups, and arylate groups may be the same or different, and may be further substituted. Further, it may be a mixture of alkylate group, cycloalkylcarboxylate group, and arylate group, and these substituents may be bonded by a covalent bond. Furthermore, the polyhydric alcohol part may be substituted, and the partial structure of the polyhydric alcohol may be part of the polymer or regularly pendant, and may be an antioxidant, an acid scavenger, an ultraviolet absorber. May be introduced into a part of the molecular structure of the additive.

  Among the ester plasticizers composed of the polyhydric alcohol and the monovalent carboxylic acid, alkyl polyhydric alcohol aryl esters are preferred. Specifically, the above-mentioned ethylene glycol dibenzoate, glycerin tribenzoate, diglycerin tetrabenzoate, Exemplified compound 16 described in paragraph 31 of JP2003-12823A can be mentioned.

  Specific examples of the dicarboxylic acid ester plasticizer that is one of polyvalent carboxylic acid esters include alkyl dicarboxylic acids such as didodecyl malonate (C1), dioctyl adipate (C4), and dibutyl sebacate (C8). Alkyl ester plasticizers, alkyl dicarboxylic acid cycloalkyl ester plasticizers such as dicyclopentyl succinate and dicyclohexyl adipate, and alkyl dicarboxylic acid aryl ester plastics such as diphenyl succinate and di-4-methylphenyl glutarate , Dicyclohexyl-1,4-cyclohexanedicarboxylate, didecylbicyclo [2.2.1] heptane-2,3-dicarboxylate and other cycloalkyldicarboxylic acid alkyl ester plasticizers, dicyclohexyl-1,2 -Cyclobutane Cycloalkyldicarboxylic acid cycloalkyl ester type plasticizers such as carboxylate and dicyclopropyl-1,2-cyclohexyldicarboxylate, diphenyl-1,1-cyclopropyldicarboxylate, di2-naphthyl-1,4- Cycloalkyldicarboxylic acid aryl ester plasticizers such as cyclohexane dicarboxylate, aryl dicarboxylic acid alkyl ester plasticizers such as diethyl phthalate, dimethyl phthalate, dioctyl phthalate, dibutyl phthalate, and di-2-ethylhexyl phthalate, dicyclopropyl Aryl dicarboxylic acid cycloalkyl ester plasticizers such as phthalate and dicyclohexyl phthalate, and aryl dicarboxylic acid esters such as diphenyl phthalate and di4-methylphenyl phthalate Ester plasticizers, glycolic acid ester plasticizers such as butyl phthalyl butyl glycolate and ethyl phthalyl ethyl glycolate, citric acid plastics such as acetyl trimethyl citrate, acetyl triethyl citrate and acetyl tributyl citrate Agents and the like. These alkoxy groups and cycloalkoxy groups may be the same or different, may be mono-substituted, and these substituents may be further substituted. The alkyl group and cycloalkyl group may be mixed, and these substituents may be bonded together by a covalent bond. Furthermore, the aromatic ring of phthalic acid may be substituted, and a multimer such as a dimer, trimer or tetramer may be used. Also, the partial structure of phthalate ester may be part of the polymer, or may be regularly pendant to the polymer, and part of the molecular structure of additives such as antioxidants, acid scavengers, UV absorbers It may be introduced.

  Examples of other polycarboxylic acid ester plasticizers include alkyl polycarboxylic acid alkyl esters such as tridodecyl tricarbarate and tributyl-meso-butane-1,2,3,4-tetracarboxylate. Plasticizers, alkylpolycarboxylic acid cycloalkyl ester plasticizers such as tricyclohexyltricarbarate, tricyclopropyl-2-hydroxy-1,2,3-propanetricarboxylate, triphenyl 2-hydroxy- Alkyl polyvalent carboxylic acid aryl ester plasticizers such as 1,2,3-propanetricarboxylate, tetra-3-methylphenyltetrahydrofuran-2,3,4,5-tetracarboxylate, tetrahexyl-1,2, 3,4-cyclobutanetetracarboxylate, tetrabu Cycloalkyl polycarboxylic acid alkyl ester plasticizers such as ru-1,2,3,4-cyclopentanetetracarboxylate, tetracyclopropyl-1,2,3,4-cyclobutanetetracarboxylate, tricyclohexyl- Cycloalkyl polycarboxylic acid cycloalkyl ester plasticizers such as 1,3,5-cyclohexyl tricarboxylate, triphenyl-1,3,5-cyclohexyl tricarboxylate, hexa-4-methylphenyl-1,2, Cycloalkyl polycarboxylic acid aryl ester plasticizers such as 3,4,5,6-cyclohexylhexacarboxylate, tridodecylbenzene-1,2,4-tricarboxylate, tetraoctylbenzene-1,2,4 , 5-tetracarboxylate and other aryl polyvalent Rubinoic acid alkyl ester plasticizers, tricyclopentylbenzene-1,3,5-tricarboxylate, tetracyclohexylbenzene-1,2,3,5-tetracarboxylate and other aryl polyvalent carboxylic acid cycloalkyl esters Plasticizers of aryl polyvalent carboxylic acid aryl esters such as plasticizers triphenylbenzene-1,3,5-tetracarboxylate, hexa-4-methylphenylbenzene-1,2,3,4,5,6-hexacarboxylate Agents. These alkoxy groups and cycloalkoxy groups may be the same or different, and may be mono-substituted, and these substituents may be further substituted. The alkyl group and cycloalkyl group may be mixed, and these substituents may be bonded together by a covalent bond. Furthermore, the aromatic ring of phthalic acid may be substituted, and a multimer such as a dimer, trimer or tetramer may be used. Also, the partial structure of phthalate ester may be part of the polymer or regularly pendant into the polymer, and introduced into part of the molecular structure of additives such as antioxidants, acid scavengers, UV absorbers, etc. May be.

  Among the ester plasticizers composed of the polyvalent carboxylic acid and the monohydric alcohol, alkyl dicarboxylic acid alkyl esters are preferable, and specific examples include the dioctyl adipate.

  Examples of other plasticizers used in the present invention include phosphate ester plasticizers, carbohydrate ester plasticizers, and polymer plasticizers.

  Specific examples of the phosphoric acid ester plasticizer include phosphoric acid alkyl esters such as triacetyl phosphate and tributyl phosphate, phosphoric acid cycloalkyl esters such as tricyclopentyl phosphate and cyclohexyl phosphate, triphenyl phosphate, and trichlorate. Examples thereof include phosphoric acid aryl esters such as zil phosphate, cresyl phenyl phosphate, octyl diphenyl phosphate, diphenyl biphenyl phosphate, trioctyl phosphate, tributyl phosphate, trinaphthyl phosphate, trixylyl phosphate, tris ortho-biphenyl phosphate. These substituents may be the same or different, and may be further substituted. Moreover, the mix of an alkyl group, a cycloalkyl group, and an aryl group may be sufficient, and substituents may couple | bond together by the covalent bond.

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

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

  Next, the carbohydrate ester plasticizer will be described. The carbohydrate means a monosaccharide, disaccharide or trisaccharide in which the saccharide is present in the form of pyranose or furanose (6-membered ring or 5-membered ring). Non-limiting examples of carbohydrates include glucose, saccharose, lactose, cellobiose, mannose, xylose, ribose, galactose, arabinose, fructose, sorbose, cellotriose and raffinose. The carbohydrate ester refers to an ester compound formed by dehydration condensation of a carbohydrate hydroxyl group and a carboxylic acid, and specifically means an aliphatic carboxylic acid ester or an aromatic carboxylic acid ester of a carbohydrate. Examples of the aliphatic carboxylic acid include acetic acid and propionic acid, and examples of the aromatic carboxylic acid include benzoic acid, toluic acid, and anisic acid. Carbohydrates have a number of hydroxyl groups depending on the type, but even if a part of the hydroxyl group reacts with the carboxylic acid to form an ester compound, the whole hydroxyl group reacts with the carboxylic acid to form an ester compound. Also good. In the present invention, it is preferable that all of the hydroxyl groups react with the carboxylic acid to form an ester compound.

  Specific examples of the carbohydrate ester plasticizer include glucose pentaacetate, glucose pentapropionate, glucose pentabylate, saccharose octaacetate, saccharose octabenzoate and the like. Among these, saccharose octaacetate, saccharose Octabenzoate is more preferred.

  Specific examples of the polymer plasticizer include aliphatic hydrocarbon polymers, alicyclic hydrocarbon polymers, polyethyl acrylate, polymethyl methacrylate, methyl methacrylate and 2-hydroxyethyl methacrylate. Polymers, acrylic polymers such as copolymers of methyl methacrylate, methyl acrylate and methacrylate-2-hydroxyethyl, vinyl polymers such as polyvinyl isobutyl ether and poly N-vinyl pyrrolidone, polystyrene, poly 4-hydroxy Examples thereof include styrene polymers such as styrene, polyesters such as polybutylene succinate, polyethylene terephthalate and polyethylene naphthalate, polyethers such as polyethylene oxide and polypropylene oxide, polyamides, polyurethanes and polyureas. The number average molecular weight is preferably about 1,000 to 500,000, particularly preferably 5,000 to 200,000. If it is 1000 or less, a problem arises in volatility, and if it exceeds 500000, the plasticizing ability is lowered, and the mechanical properties of the cellulose ester film are adversely affected. These polymer plasticizers may be a homopolymer composed of one type of repeating unit or a copolymer having a plurality of repeating structures. Two or more of the above polymers may be used in combination.

  The cellulose ester film used in the present invention contains 1 to 25% by mass of an ester plasticizer comprising a polyhydric alcohol and a monovalent carboxylic acid, and an ester plasticizer comprising a polyvalent carboxylic acid and a monohydric alcohol. However, it may be used in combination with other plasticizers.

  In the cellulose ester film used in the present invention, an ester plasticizer comprising a polyhydric alcohol and a monovalent carboxylic acid is more preferred, but an ester plasticizer comprising a trivalent or higher alcohol and a monovalent carboxylic acid is a cellulose ester. High compatibility and high addition rate, so there is no bleed out even when other plasticizers and additives are used together. And additives are most preferable because they can be easily used together.

<Ultraviolet absorber>
Examples of the ultraviolet absorber used in the melt casting method include the aforementioned oxybenzophenone compounds, benzotriazole compounds, salicylic acid ester compounds, benzophenone compounds, cyanoacrylate compounds, nickel complex compounds, triazine compounds, and the like. However, a benzophenone compound, a benzotriazole compound and a triazine compound with little coloring are preferable. Further, ultraviolet absorbers described in JP-A Nos. 10-182621 and 8-337574, and polymer ultraviolet absorbers described in JP-A Nos. 6-148430 and 2003-113317 may be 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 Co., Ltd.), and RUVA-100 (manufactured by Otsuka Chemical).

  In this invention, it is preferable to add 0.1-10 mass% of ultraviolet absorbers with respect to the mass of a cellulose ester, Furthermore, it is preferable to add 0.2-5 mass%, Furthermore, 0.5- It is preferable to add 3% by mass. Two or more of these may be used in combination.

  The benzotriazole structure or triazine structure may be part of the polymer, or may be regularly pendant to the polymer, and part of the molecular structure of other additives such as plasticizers, antioxidants, and acid scavengers. May be introduced.

  Although it does not specifically limit as a conventionally well-known ultraviolet absorptive polymer, For example, the polymer which homopolymerized RUVA-93 (made by Otsuka Chemical), the polymer which copolymerized RUVA-93, and another monomer, etc. are mentioned. . Specific examples include PUVA-30M obtained by copolymerization of RUVA-93 and methyl methacrylate at a ratio (mass ratio) of 3: 7, and PUVA-50M obtained by copolymerization at a ratio of 5: 5 (mass ratio). It is done. Furthermore, the polymer etc. which are described in Unexamined-Japanese-Patent No. 2003-113317 are mentioned.

<Other additives>
Other additives include, for example, the aforementioned acrylic polymer, matting agent, filler, inorganic compounds such as silica and silicate, dyes, pigments, phosphors, dichroic dyes, retardation control agents, refractive index adjusting agents, Examples thereof include a gas permeation inhibitor, an antibacterial agent, and a biodegradability imparting agent. Moreover, the additive which is not classified into this can be used if it has the said function.

  Then, as a method of incorporating these additives into the cellulose ester, each material is mixed in a solid or liquid state, heated and melted and kneaded to obtain a uniform melt, and then cast into a transparent resin film. Even in the formation method, all materials are dissolved in advance using a solvent to obtain a uniform solution, and then the solvent is removed to form a mixture of the additive and the cellulose ester, which is heated and melted. The transparent resin film may be formed by casting.

"Polarizer"
A polarizing plate using the antireflection film of 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 590 nm, an optical compensation film having a phase difference of 20 to 70 nm and Rt of 100 to 400 nm. A phase difference film). These can be prepared, for example, by the methods described in JP-A No. 2002-71957 and Japanese Patent Application No. 2002-155395. Alternatively, it is preferable to use a polarizing plate protective film that also serves as an optical compensation film having an optically anisotropic layer formed by aligning a liquid crystal compound such as a discotic liquid crystal. For example, the optically anisotropic layer can be formed by the method described in JP-A-2003-98348. Alternatively, a non-oriented film with Ro of 590 nm to 0 to 5 nm and 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) is 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.

<Display device>
By incorporating the antireflection film surface of the present invention on the viewing surface side of the display device, various display devices of the present invention having excellent visibility can be produced. The antireflection film of the present invention is incorporated in the polarizing plate, and is reflective, transmissive, transflective LCD or TN, STN, OCB, HAN, VA (PVA, MVA), IPS, 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 display devices such as paper.

  In particular, the antireflection film of the present invention was processed as a front plate filter of a plasma display, and the mounted plasma display was a display device having excellent visibility without light interference unevenness. In addition, even a 30-inch or larger large-screen plasma display display device has the effect of reducing color unevenness and wavy unevenness, and preventing eyestrain from being watched for a long time. The antireflection film of the present invention also had good antistatic properties.

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

  The ionic liquid used for the Example first is shown below.

Ionic liquid 1: 1-butyl-3-methylimidazolium octylsulfate
Ionic liquid 2: 1-butyl-3-methylimidazolium hexafluorophosphate
Ionic liquid 3: 1-ethyl-2,3,5-trimethylpyrazolium bistrifluoromethanesulfonylimide Ionic liquid 4: 1-ethyl-3-methylimidazolium trifluoromethanesulfonate Ionic liquid 5: Glycidyltrimethylammonium trifluoromethanesulfonate ion Liquid 6: Glycidyltrimethylammonium bis (trifluoromethanesulfonyl) imide Ionic liquid 7: 1-Butyl-3-methylpyridinium bis (trifluoromethanesulfonyl) imide Ionic liquid 8: Diallyldimethylammonium bis (trifluoromethanesulfonyl) imide Example 1
(Production of cellulose ester films 1 to 6)
<Preparation of dope solution>
The following materials were sequentially put into a sealed container, the temperature in the container was raised from 20 ° C. to 80 ° C., and the mixture was stirred for 3 hours while maintaining the temperature at 80 ° C. to completely dissolve the cellulose ester. . The silicon oxide fine particles were added dispersed in a solution of a solvent to be added in advance and a small amount of cellulose ester. This dope was filtered using a filter paper (Azumi filter paper No. 244 manufactured by Azumi Filter Paper Co., Ltd.) to obtain a dope liquid A, a dope liquid B, and a dope liquid C.

(Preparation of dope solution A)
Cellulose ester (cellulose triacetate; acetyl group substitution degree 2.9)
100 parts by mass Trimethylolpropane tribenzoate 5 parts by mass Ethylphthalyl ethyl glycolate 5 parts by mass Silicon oxide fine particles (Aerosil R972V (produced by Nippon Aerosil Co., Ltd.))
0.1 parts by weight Tinuvin 109 (manufactured by Ciba Specialty Chemicals) 1 part by weight Tinuvin 171 (manufactured by Ciba Specialty Chemicals) 1 part by weight Methylene chloride 400 parts by weight Ethanol 40 parts by weight Butanol 5 parts by weight The dope solution prepared as described above A is passed through a casting die kept at 35 ° C. onto a 35 ° C. support made of a stainless steel endless belt to form a web, dried on the support, and the residual solvent amount of the web is 80 After drying on a support until it became mass%, the web was peeled from the support with a peeling roll.

  Next, the web is transported while being dried with a drying air of 90 ° C. in a transport and drying process using a plurality of rolls arranged on the top and bottom, subsequently gripping both end portions of the web with a tenter, and then before stretching in the width direction at 130 ° C. The film was stretched so as to be 1 time. After stretching with a tenter, the web was dried with a drying air of 135 ° C. in a transport drying process using a plurality of rolls arranged vertically. After heat-treating for 15 minutes in an atmosphere with an atmosphere substitution rate of 15 (times / hour) in the drying process, the film was cooled to room temperature and wound up. A long cellulose ester film 1 was produced. The draw ratio in the web conveyance direction immediately after peeling calculated from the rotational speed of the stainless steel band support and the operating speed of the tenter was 1.1 times.

  A cellulose ester film 2 was produced in the same manner except that the film thickness was 40 μm.

Note that the atmosphere substitution rate is expressed in terms of Fresh-air as the atmosphere per unit time determined by the following equation when the atmosphere capacity is V (m ³ ) and the fresh air flow rate is FA (m ³ / hr) in the heat treatment chamber. The number of replacements.

Atmosphere replacement rate = FA / V (times / hour)
Cellulose ester film 3 (film thickness 80 μm) and cellulose ester film 4 (film thickness 40 μm) were produced in the same manner except that dope liquid A was changed to dope liquid B.

(Preparation of dope solution B)
Dope B was obtained in the same manner except that the material used was changed to the following material.

Cellulose ester (cellulose acetate propionate; acetyl group substitution degree 1.9, propionyl group substitution degree 0.9) 100 parts by weight Triphenyl phosphate 10 parts by weight Biphenyl diphenyl phosphate 2 parts by weight Silicon oxide fine particles (Aerosil R972V (Nippon Aerosil Co., Ltd.) Company-made))
0.1 parts by weight Tinuvin 109 (manufactured by Ciba Specialty Chemicals) 1 part by weight Tinuvin 171 (manufactured by Ciba Specialty Chemicals) 1 part by weight Methyl acetate 300 parts by weight Ethanol 70 parts by weight Butanol 5 parts by weight Dope solution A as dope solution C A cellulose ester film 5 (film thickness of 80 μm) and a cellulose ester film 6 (film thickness of 40 μm) were produced in the same manner except for the change.

(Preparation of dope solution C)
Dope C was obtained in the same manner except that the material used was changed to the following material.

Cellulose ester (cellulose acetate propionate; acetyl group substitution degree 1.9, propionyl group substitution degree 0.9) 100 parts by mass Trimethylolpropane tribenzoate 5 parts by mass Copolymer of methyl acrylate and 2-hydroxyethyl methacrylate (each Molar ratio of monomer component 9: 1, weight average molecular weight 4000) 8 parts by mass Silicon oxide fine particles (Aerosil R972V (produced by Nippon Aerosil Co., Ltd.))
0.1 parts by weight Tinuvin 109 (manufactured by Ciba Specialty Chemicals) 1 part by weight Tinuvin 171 (manufactured by Ciba Specialty Chemicals) 1 part by weight Methylene chloride 325 parts by weight Ethanol 70 parts by weight Butanol 5 parts by weight (cellulose ester by melt casting method) Production of films 7 and 8)
<Cellulose ester>
C-1: Cellulose acetate propionate (acetyl group substitution degree 1.3, propionyl group substitution degree 1.3, molecular weight Mn = 60000, molecular weight Mw = 18000, Mw / Mn = 3)
<Plasticizer>
Trimethylolpropane tribenzoate (additive)
Additive a IRGANOX-1010 (Ciba Specialty Chemicals)
Additive b Sumilizer GS (manufactured by Sumitomo Chemical Co., Ltd.)
Additive c GSY-P101 (manufactured by Sakai Chemical Industry Co., Ltd.)
<Ultraviolet absorber>
Tinuvin 360 (manufactured by Ciba Specialty Chemicals)
<Matting agent>
Aerosil 200V (0.016μm silica fine particles, manufactured by Nippon Aerosil Co., Ltd.)
Cellulose ester C-1 100 parts by mass, plasticizer 10 parts by mass, additive a 0.5 parts by mass, additive b 0.3 parts by mass, additive c 0.3 parts by mass, ultraviolet absorber 0.5 parts by mass Part, 0.2 part by mass of matting agent was added and mixed for 30 minutes with a tumbler mixer.

  The obtained mixture was dried by a dehumidifying hot air dryer (Matsui Seisakusho DMZ2) at a hot air temperature of 150 ° C. and a dew point of −36 ° C. Next, in a nitrogen atmosphere, this mixture was supplied to a Technobel Co., Ltd. twin-screw extruder, melted at 250 ° C., and melt-extruded at a draw ratio of 15 to each elastic touch roll whose temperature was adjusted to 120 ° C. The sheet was conveyed between the roll and the cooling roll, passed between the three take-up rolls and stretched 1.5 times in the width direction by a tenter, and then the edge was slit and wound around a winder.

  The thickness of the wound film was adjusted by the amount of extrusion and the rotational speed of the take-up roll to produce a cellulose ester film 7 (film thickness 80 μm) and a cellulose ester film 8 (film thickness 40 μm) having a width of 2.3 m.

(Preparation of antireflection film)
The above prepared cellulose ester films 1 to 8 and the following commercially available cellulose ester films (Konica Minoltak KC8UX2MW, KC4UY, KC4UE, KC4FR-1, KC8UCR-5, manufactured by Konica Minolta Opto Co., Ltd.) support (transparent resin film) ) And an antireflection film was prepared according to the following procedure.

Cellulose ester film 9: Konica Minoltack KC8UX2MW
Cellulose ester film 10: Konica Minoltack KC4UY
Cellulose ester film 11: Konica Minolta KC4UE
Cellulose ester film 12: Konica Minoltack KC4FR-1
Cellulose ester film 13: Konica Minoltack KC8UCR-5
The refractive index of each layer constituting the antireflection layer was measured by the following method.

(Refractive index)
The refractive index of each refractive index layer was calculated | required from the measurement result of the spectral reflectance of the spectrophotometer about the sample which coated each layer on the hard coat film produced below. The spectrophotometer uses U-4000 type (manufactured by Hitachi, Ltd.), and after roughening the back side of the measurement side of the sample, light absorption treatment is performed with black spray to prevent reflection of light on the back side. The reflectance in the visible light region (400 nm to 700 nm) was measured under the condition of regular reflection at 5 degrees.

(Particle size of metal oxide fine particles)
As for the particle diameter of the metal oxide fine particles used, 100 fine particles were observed with an electron microscope (SEM), the diameter of a circle circumscribing each fine particle was taken as the particle diameter, and the average value was taken as the particle diameter.

<< Production of hard coat film >>
On the produced cellulose ester film 1, the following hard coat layer composition is filtered through a polypropylene filter having a pore size of 0.4 μm to prepare a hard coat layer coating solution, which is applied using a micro gravure coater, After drying at 90 ° C., an ultraviolet lamp is used to cure the coating layer with an illuminance of the irradiated part of 100 mW / cm ² and an irradiation amount of 0.2 J / cm ² to form a hard coat layer having a dry film thickness of 10 μm. Coat film 1 was produced.

  The following back coat layer composition 1 was applied on the surface opposite to the surface coated with the hard coat layer so as to have a wet film thickness of 14 μm by an extrusion coater and dried at 85 ° C.

(Hard coat layer composition 1)
The following materials were stirred and mixed to obtain hard coat layer composition 1.

Pentaerythritol triacrylate 20 parts by mass Pentaerythritol tetraacrylate 60 parts by mass Urethane acrylate (trade name U-4HA manufactured by Shin-Nakamura Chemical Co., Ltd.) 50 parts by mass Irgacure 184 (manufactured by Ciba Specialty Chemicals) 20 parts by mass Irgacure 907 (Ciba Specialty Chemicals Co., Ltd.) 12 parts by weight Polyether-modified silicone oil (KF-351, Shin-Etsu Chemical Co., Ltd.) 0.8 parts by weight Polyoxyalkyl ether (Emulgen 1108, Kao Corporation) 1.0 part by weight Propylene glycol monomethyl ether 110 110 parts by mass of ethyl acetate <Backcoat layer composition 1>
Acetone 54 parts by weight Methyl ethyl ketone 24 parts by weight Methanol 22 parts by weight Cellulose ester (cellulose acetate propionate; acetyl group substitution degree 1.9, propionyl group substitution degree 0.8) 0.6 part by weight Ultrafine silica 2% acetone dispersion (Aerosil 200V manufactured by Nippon Aerosil Co., Ltd.) 0.2 parts by mass Similarly, the film thickness of the cellulose ester film, the hard coat layer composition, and the hard coat layer is changed as shown in Table 1, and the hard coat film 2 to 25 were produced.

(Hard coat layer composition 2)
The following materials were stirred and mixed to obtain hard coat layer composition 2.

Acrylic monomer; KAYARAD DPHA (dipentaerythritol hexaacrylate, Nippon Kayaku) 220 parts by mass Irgacure 184 (manufactured by Ciba Specialty Chemicals) 20 parts by mass Silicone surfactant (FZ-2207, manufactured by Nippon Unicar Co., Ltd.) ) 10% propylene glycol monomethyl ether solution 2 parts by weight Propylene glycol monomethyl ether 110 parts by weight Ethyl acetate 110 parts by weight (Hardcoat layer composition 3)
The following materials were stirred and mixed to obtain hard coat layer composition 3.

Acrylic monomer; KAYARAD DPHA (dipentaerythritol hexaacrylate, manufactured by Nippon Kayaku) 220 parts by mass Irgacure 184 (manufactured by Ciba Specialty Chemicals) 20 parts by mass Ionic liquid 1 20 parts by mass Silicone surfactant (FZ-2207, Nippon Unicar Co., Ltd.) 10% propylene glycol monomethyl ether solution 2 parts by weight propylene glycol monomethyl ether 110 parts by weight ethyl acetate 110 parts by weight (hard coat layer composition 4)
The following materials were stirred and mixed to obtain hard coat layer composition 4.

Pentaerythritol triacrylate 20 parts by mass Pentaerythritol tetraacrylate 60 parts by mass Urethane acrylate (trade name U-4HA manufactured by Shin-Nakamura Chemical Co., Ltd.) 50 parts by mass Irgacure 184 (manufactured by Ciba Specialty Chemicals) 20 parts by mass Irgacure 907 (Ciba Specialty Chemicals Co., Ltd.) 12 parts by mass Polyether-modified silicone oil (KF-351, Shin-Etsu Chemical Co., Ltd.) 0.8 parts by mass Polyoxyalkyl ether (Emulgen 1108, manufactured by Kao Corporation) 1.0 part by mass Ionic liquid 2 5 parts by mass Parts propylene glycol monomethyl ether 110 parts by weight ethyl acetate 110 parts by weight (hard coat layer composition 5)
The following materials were stirred and mixed to obtain hard coat layer composition 5 (antiglare hard coat layer).

Pentaerythritol triacrylate 20 parts by mass Pentaerythritol tetraacrylate 60 parts by mass Urethane acrylate (trade name U-4HA manufactured by Shin-Nakamura Chemical Co., Ltd.) 50 parts by mass Irgacure 184 (manufactured by Ciba Specialty Chemicals) 20 parts by mass Irgacure 907 (Ciba Specialty Chemicals Co., Ltd.) 12 parts by mass Polyether-modified silicone oil (KF-351, Shin-Etsu Chemical Co., Ltd.) 0.8 parts by mass Polyoxyalkyl ether (Emulgen 1108, Kao Corporation) 1.0 part by mass Cross-linked polystyrene particles Average primary Particle size 3.5 μm 5 parts by mass Silica particles Particle size 0.1 μm 5 parts by mass Ionic liquid 3 1 part by mass Propylene glycol monomethyl ether 110 parts by mass Ethyl acetate 110 parts by mass (Hardcoat layer composition 6)
The following materials were stirred and mixed to obtain hard coat layer composition 6.

Acrylic monomer; KAYARAD DPHA (dipentaerythritol hexaacrylate, Nippon Kayaku) 220 parts by mass Irgacure 184 (manufactured by Ciba Specialty Chemicals) 20 parts by mass Ionic liquid 5 10 parts by mass Silicon-based surfactant (FZ-2207, Nippon Unicar Co., Ltd.) 10% propylene glycol monomethyl ether solution 2 parts by weight propylene glycol monomethyl ether 110 parts by weight ethyl acetate 110 parts by weight (hard coat layer composition 7)
The following materials were stirred and mixed to obtain hard coat layer composition 7.

Acrylic monomer; KAYARAD DPHA (dipentaerythritol hexaacrylate, manufactured by Nippon Kayaku) 220 parts by mass Irgacure 184 (manufactured by Ciba Specialty Chemicals) 20 parts by mass Ionic liquid 6 10 parts by mass Silicon-based surfactant (FZ-2207, Nippon Unicar Co., Ltd.) 10% propylene glycol monomethyl ether solution 2 parts by weight propylene glycol monomethyl ether 110 parts by weight ethyl acetate 110 parts by weight (hard coat layer composition 8)
The following materials were stirred and mixed to obtain hard coat layer composition 8.

Acrylic monomer; KAYARAD DPHA (dipentaerythritol hexaacrylate, Nippon Kayaku) 220 parts by mass Irgacure 184 (manufactured by Ciba Specialty Chemicals) 20 parts by mass Ionic liquid 7 10 parts by mass Silicon-based surfactant (FZ-2207, Nippon Unicar Co., Ltd.) 10% propylene glycol monomethyl ether solution 2 parts by weight Propylene glycol monomethyl ether 110 parts by weight Ethyl acetate 110 parts by weight (Hardcoat layer composition 9)
The following materials were stirred and mixed to obtain hard coat layer composition 9.

Acrylic monomer; KAYARAD DPHA (dipentaerythritol hexaacrylate, Nippon Kayaku) 220 parts by mass Irgacure 184 (manufactured by Ciba Specialty Chemicals) 20 parts by mass Ionic liquid 8 10 parts by mass Silicon-based surfactant (FZ-2207, Nippon Unicar Co., Ltd.) 10% propylene glycol monomethyl ether solution 2 parts by weight propylene glycol monomethyl ether 110 parts by weight ethyl acetate 110 parts by weight (hard coat layer composition 10)
The following materials were stirred and mixed to obtain a hard coat layer composition 10.

Acrylic monomer; KAYARAD DPHA (dipentaerythritol hexaacrylate, Nippon Kayaku) 220 parts by mass Irgacure 184 (manufactured by Ciba Specialty Chemicals) 20 parts by mass Ionic liquid 4 2 parts by mass Silicon-based surfactant (FZ-2207, Nippon Unicar Co., Ltd.) 10% propylene glycol monomethyl ether solution 2 parts by mass Propylene glycol monomethyl ether 110 parts by mass Ethyl acetate 110 parts by mass

<< Preparation of antireflection films 101-144 >>
On the hard coat film 1 produced as described above, an antireflection film 101 was produced by coating an antireflection layer in the order of a high refractive index layer and then a low refractive index layer as follows.

<Preparation of antireflection layer: high refractive index layer>
On the hard coat film 1, the following high refractive index layer coating composition 1 is applied by an extrusion coater, dried at 80 ° C. for 1 minute, then cured by irradiation with ultraviolet rays of 0.1 J / cm ² , and further at 100 ° C. The high refractive index layer 1 was provided so as to be thermally cured for 1 minute and to have a thickness of 78 nm.

  The refractive index of this high refractive index layer was 1.6.

(High refractive index layer coating composition 1)
Isopropyl alcohol solution of metal oxide fine particles (solid content 20%, ITO particles, primary average particle diameter 50 nm) 55 parts by mass Metal compound: Ti (OBu) ₄ (tetra-n-butoxytitanium) 1.3 parts by mass Ionizing radiation curing Mold resin: Dipentaerythritol hexaacrylate
3.2 parts by mass Photopolymerization initiator: Irgacure 184 (manufactured by Ciba Specialty Chemicals)
0.8 part by mass Ionic liquid 1 0.3 part by mass 10% propylene glycol monomethyl ether solution of silicon surfactant (FZ-2207, manufactured by Nippon Unicar Co., Ltd.) 1.5 parts by mass Propylene glycol monomethyl ether 120 parts by mass Isopropyl alcohol 240 parts by weight Methyl ethyl ketone 40 parts by weight (High refractive index layer coating composition 2)
Isopropyl alcohol solution of metal oxide fine particles (solid content 20%, ITO particles, primary average particle diameter 50 nm) 55 parts by mass Metal compound: Ti (OBu) ₄ (tetra-n-butoxytitanium) 1.3 parts by mass Pentaerythritol tri Acrylate 1.2 parts by mass Pentaerythritol tetraacrylate 1.3 parts by mass Urethane acrylate (trade name: U-4HA, Shin-Nakamura Chemical Co., Ltd.) 0.7 parts by mass Photopolymerization initiator: Irgacure 184 (Ciba Specialty Chemicals Co., Ltd.) Made)
1.8 parts by mass Ionic liquid 4 0.2 parts by mass 10% propylene glycol monomethyl ether solution of silicon surfactant (FZ-2207, manufactured by Nippon Unicar Co., Ltd.) 1.5 parts by mass Propylene glycol monomethyl ether 120 parts by mass Isopropyl alcohol 240 parts by weight Methyl ethyl ketone 40 parts by weight (High refractive index layer coating composition 3)
<Preparation of particle dispersion A>
Methanol-dispersed antimony double oxide colloid (solid content 60%, zinc antimonate sol manufactured by Nissan Chemical Industries, Ltd., trade name: Celnax CX-Z610M-F2) 6.0 kg of isopropyl alcohol was gradually stirred with stirring. To prepare a particle dispersion A.

PGME (propylene glycol monomethyl ether) 40 parts by mass Isopropyl alcohol 25 parts by mass Methyl ethyl ketone 25 parts by mass Pentaerythritol triacrylate 0.9 parts by mass Pentaerythritol tetraacrylate 1.0 part by mass Urethane acrylate (trade name: U-4HA Shin-Nakamura Chemical 0.6 parts by mass Ionic liquid 3 0.1 parts by mass Particle dispersion A 20 parts by mass Irgacure 184 (manufactured by Ciba Specialty Chemicals) 0.4 parts by mass Irgacure 907 (manufactured by Ciba Specialty Chemicals) 0.2 part by mass 10% propylene glycol monomethyl ether solution of silicon-based surfactant (FZ-2207, manufactured by Nippon Unicar Co., Ltd.) 0.4 part by mass (high refractive index layer coating composition 4)
Isopropyl alcohol solution of metal oxide fine particles (solid content 20%, ITO particles, primary average particle diameter 50 nm) 55 parts by mass Metal compound: Ti (OBu) ₄ (tetra-n-butoxytitanium) 1.3 parts by mass Ionizing radiation curing Type resin: dipentaerythritol hexaacrylate 3.2 parts by mass Photopolymerization initiator: Irgacure 184 (manufactured by Ciba Specialty Chemicals)
2.8 parts by mass 10% propylene glycol monomethyl ether solution of silicon surfactant (FZ-2207, manufactured by Nippon Unicar Co., Ltd.) 1.5 parts by mass Propylene glycol monomethyl ether 120 parts by mass Isopropyl alcohol 240 parts by mass Methyl ethyl ketone 40 parts by mass Part (High refractive index layer coating composition 5)
<Preparation of particle dispersion A>
Methanol-dispersed antimony double oxide colloid (solid content 60%, zinc antimonate sol manufactured by Nissan Chemical Industries, Ltd., trade name: Celnax CX-Z610M-F2) 6.0 kg of isopropyl alcohol was gradually stirred with stirring. To prepare a particle dispersion A.

PGME (propylene glycol monomethyl ether) 40 parts by mass Isopropyl alcohol 25 parts by mass Methyl ethyl ketone 25 parts by mass Pentaerythritol triacrylate 0.9 parts by mass Pentaerythritol tetraacrylate 1.0 part by mass Urethane acrylate (trade name: U-4HA Shin-Nakamura Chemical 0.6 parts by mass Particle dispersion A 20 parts by mass Irgacure 184 (manufactured by Ciba Specialty Chemicals) 0.4 parts by mass Irgacure 907 (manufactured by Ciba Specialty Chemicals) 0.2 parts by mass Silicon-based interface 0.4% by mass of 10% propylene glycol monomethyl ether solution of activator (FZ-2207, Nippon Unicar Co., Ltd.) << Preparation of antireflection layer: low refractive index layer >>
On the high refractive index layer, the following low refractive index layer coating composition 1 is applied by an extrusion coater, dried at 100 ° C. for 1 minute, cured by irradiation with ultraviolet rays of 0.1 J / cm ² , and Heat-cured at 120 ° C. for 5 minutes, a low refractive index layer was provided so as to have a thickness of 95 nm, and an antireflection film 101 shown in Table 2 was produced. The refractive index of this low refractive index layer was 1.37.

(Low refractive index layer coating composition 1)
<Preparation of tetraethoxysilane hydrolyzate A>
Tetraethoxysilane hydrolyzate A 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 the mixture at room temperature (25 ° C.) for 26 hours.

Propylene glycol monomethyl ether 430 parts by mass Isopropyl alcohol 430 parts by mass Tetraethoxysilane hydrolyzate A 120 parts by mass γ-methacryloxypropyltrimethoxysilane (trade name: KBM503, manufactured by Shin-Etsu Chemical Co., Ltd.) 3 parts by mass Isopropyl alcohol-dispersed hollow silica sol (Solid content 20%, Silica sol manufactured by Catalyst Kasei Kogyo Co., Ltd., trade name: ELCOM V-8209) 40 parts by mass Aluminum ethyl acetoacetate diisopropylate 3 parts by mass Silicone surfactant (FZ-2207, Nippon Unicar Co., Ltd.) 3% by weight of 10% propylene glycol monomethyl ether solution manufactured on the hard coat films 2 to 30 except that the hard coat film, the high refractive index layer composition and the low refractive index layer composition shown in Table 2 were changed. , Anti In the same manner as the antireflection film 101 provided with the high refractive index layer and a low refractive index layer, thereby fabricating an antireflection film 102-144.

(Preparation of low refractive index layer coating composition 2)
<Preparation of tetraethoxysilane hydrolyzate A>
Tetraethoxysilane hydrolyzate A 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 the mixture at room temperature (25 ° C.) for 26 hours.

Propylene glycol monomethyl ether 430 parts by mass Isopropyl alcohol 430 parts by mass Tetraethoxysilane hydrolyzate A 120 parts by mass γ-methacryloxypropyltrimethoxysilane (trade name: KBM503, manufactured by Shin-Etsu Chemical Co., Ltd.) 3.0 parts by mass Isopropyl alcohol dispersion Hollow silica sol (solid content 20%, silica sol manufactured by Catalyst Kasei Kogyo Co., Ltd., trade name: ELCOM V-8209) 40 parts by mass Aluminum ethyl acetoacetate diisopropylate 3.0 parts by mass Ionic liquid 1 0.3 parts by mass Silicon-based interface 3 parts by mass of 10% propylene glycol monomethyl ether liquid of activator (FZ-2207, manufactured by Nippon Unicar Co., Ltd.) <Heat treatment of antireflection film>
The produced antireflection films 101 to 144 were each wound around a plastic core with a winding length of 2500 m. Using this antireflection film roll, heat treatment was performed at 80 ° C. for 4 days in a heat treatment chamber.

"Evaluation methods"
The produced antireflection film samples were evaluated by the following methods. The evaluation results are shown in Table 2.

(Reflectance)
Using a spectrophotometer (U-4000, manufactured by Hitachi, Ltd.), the spectral reflectance at an incident angle of 5 ° was measured in a wavelength region of 380 to 780 nm. Since the antireflection performance is better as the reflectance is smaller in a wide wavelength region, the minimum reflectance at 450 to 650 nm is obtained from the measurement result. In the measurement, the back surface on the observation side was roughened, and then light absorption processing was performed using a black spray to prevent reflection of light on the back surface of the film, and the reflectance was measured.

  As a result, the reflectance of each of the antireflection films 101 to 144 was less than 1%.

(Evaluation of muscle failure)
The streaks on the film surface were visually observed and evaluated based on the following criteria.

Evaluation criteria:
◎: Excellent level without failure ○: Very few muscle failures, but in practically negligible range, good level △: Average level of conventional products that can be practically used although there are some muscle failures ×: Unusable because of many muscle failures (evaluation of reflection color unevenness)
The reflection color unevenness was visually evaluated according to the following criteria.

◎: Change in color tone of reflected light is not recognized ○: Change in color tone of reflected light is recognized in a small part (less than 10% of area)
Δ: Partial change in color of reflected light is recognized (10% or more and less than 30% of area)
X: Change in color tone of reflected light is recognized as a whole

  It is clear that the antireflection films 101 to 130 of the present invention are excellent in muscle failure and uneven reflection color. Moreover, it turns out that the effect of this invention improves more by containing the ionic liquid which concerns on this invention in a high refractive index layer.

Example 2
Next, polarizing plates were produced as follows using the antireflection films 101 to 144 produced in Example 1, and these polarizing plates were incorporated into a liquid crystal display panel (image display device) to evaluate the visibility.

  In accordance with the following method, polarizing plates 101 to 144 are prepared using one of each of the above antireflection films 101 to 144 and KC4FR-1 (manufactured by Konica Minolta Opto Co., Ltd.) as a polarizing plate protective film. Produced.

(A) Production of polarizing film 100 parts by mass of polyvinyl alcohol (hereinafter abbreviated as PVA) having a saponification degree of 99.95 mol% and a polymerization degree of 2400 was melt-kneaded with 10 parts by mass of glycerin and 170 parts by mass of water. After defoaming, the film was melt extruded from a T die onto a metal roll to form a film. Then, it dried and heat-processed and obtained the PVA film. The obtained PVA film had an average thickness of 40 μm, a moisture content of 4.4%, and a film width of 3 m.

  The aforementioned PVA film was processed in the order of pre-swelling, dyeing, uniaxial stretching by a wet method, fixing treatment, drying, and heat treatment to produce a polarizing film. The PVA film was pre-swelled by immersing it in water at 30 ° C. for 30 seconds and immersed in an aqueous solution at 35 ° C. having an iodine concentration of 0.4 g / liter and a potassium iodide concentration of 40 g / liter for 3 minutes. Subsequently, the film was uniaxially stretched 6 times in an aqueous solution of boric acid concentration 4% at 50 ° C. under a tension of 700 N / m. The potassium iodide concentration 40 g / liter, boric acid concentration 40 g / liter, Fixation was performed by immersing in an aqueous solution at 30 ° C. with a zinc chloride concentration of 10 g / liter for 5 minutes. Thereafter, the PVA film was taken out, dried with hot air at 40 ° C., and further subjected to heat treatment at 100 ° C. for 5 minutes. The obtained polarizing film had an average thickness of 15 μm.

(B) Preparation of polarizing plate Subsequently, according to the following processes 1-5, the polarizing film and the protective film for polarizing plates were bonded together, and the polarizing plates 101-144 were produced.

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

  Similarly, the optical compensation film was immersed in a 2 mol / L sodium hydroxide solution at 60 ° C. for 90 seconds, then washed with water and dried.

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

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

Process 4: It bonded together at the speed | rate of 10 m / min with the pressure of 20-30 N / cm < ² > with the two rotating rollers. At this time, care was taken to prevent bubbles from entering.

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

  A polarizing plate on the outermost surface of a commercially available liquid crystal display panel (VA type) was carefully peeled off, and polarizing plates 101 to 144 having the same polarization direction were attached thereto.

  The liquid crystal panels 1 to 56 obtained as described above are placed on a desk 80 cm high from the floor, and a daylight direct fluorescent lamp (FLR40S · D / MX) is placed on the ceiling 3 m high from the floor. Matsushita Electric Industrial Co., Ltd.) 40W × 2 were set as one set, and 10 sets were arranged at 1.5 m intervals. At this time, 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 by 25 ° from the vertical direction with respect to the desk, and a fluorescent lamp was reflected so that the visibility of the screen (visibility) was evaluated as follows.

A: You don't have to worry about the movement of the nearest fluorescent light, and you can clearly read characters with a font size of 8 or less. B: The reflection of the nearby fluorescent light is a little worrisome, but you don't care about the distance. Can manage to read characters with a font size of 8 or less C: It is difficult to read characters with a font size of 8 or less. Worrying, the imprinted part cannot read characters with a font size of 8 or less. As a result of the evaluation, both the antireflection film of the present invention and the liquid crystal panel using the polarizing plate have an evaluation result of B or more. Visibility was better than a liquid crystal panel using a comparative antireflection film and a polarizing plate.

  Moreover, in the said polarizing plate preparation process, it is the same except having changed KC4FR-1 (made by Konica Minolta Opto Co., Ltd.) which is a cellulose ester type optical compensation film into a cellulose ester film KC4UE (made by Konica Minolta Opto Co., Ltd.). Thus, polarizing plates 201 to 244 were produced.

  The polarizing plates on both sides of a commercially available liquid crystal display panel (IPS type) were carefully peeled off, and polarizing plates 201 to 244 having the same polarization direction were attached thereto. As a result of the evaluation, both the antireflection film of the present invention and the liquid crystal panel using the polarizing plate were evaluation results of B or more, and the visibility was better than the liquid crystal panel using the comparative antireflection film and the polarizing plate. . In particular, the evaluation using the antireflection film in which the ionic liquid according to the present invention is contained in the high refractive index layer has a visibility evaluation of A.

Claims (4)

In the antireflection film having a hard coat layer and an antireflection layer on at least one surface of the transparent resin film, at least one layer contains an ionic liquid ,
The antireflective layer has a high refractive index layer, the high refractive index layer contains an ionic liquid;
The antireflective film, wherein the high refractive index layer has a refractive index of 1.5 to 2.2 . The antireflection film according to claim 1, wherein the antireflection layer has a low refractive index layer, and the low refractive index layer contains hollow silica-based fine particles. A polarizing plate comprising the antireflection film according to claim 1 or 2 bonded to at least one surface of a polarizer. The antireflection film according to claim 1 or 2, the display device characterized by using the polarizing plate according to or claim 3,.