JP2010139941A - Hard coat film, method of manufacturing hard coat film, sheet polarizer and display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hard coat film having high hardness, and restraining blocking due to winding compaction of the film to attain excellent flatness, and a method of manufacturing the hard coat film. <P>SOLUTION: In this hard coat film having a hard coat layer on a transparent film base material, the film thickness of the hard coat layer is 8-40 μm, and the transparent film base contains cellulose ester resin generated by esterification reaction between polybasic acid or its anhydride and polyhydric alcohol, or ring-opening polymerization of L-lactide and D-lactide in the presence of cellulose ester. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a hard coat film, a method for producing a hard coat film, a polarizing plate, and a display device.

  In recent years, as the performance of the outermost surface of the image display device, it is easily damaged by physical damage, and if it is damaged, the quality of the displayed image is impaired. Therefore, a film having a hard coat material as a protective layer (hereinafter referred to as a hard coat film) is used on the surface. Display bodies such as provided liquid crystal displays and plasma displays are rapidly spreading. In particular, since the liquid crystal display is enlarged and used by an unspecified number of consumers, the hard coat material used for the liquid crystal display is required to have higher hardness. However, if the thickness of the hard coat layer is increased in order to obtain higher hardness, there is a problem that curling due to curing shrinkage of the hard coat layer increases.

  Also, for example, when a hard coat layer and a surface on which a hard coat layer is not formed are overlapped in a state where a high temperature and high humidity period such as summer is assumed, or the hard coat film is wound in a roll shape. If you keep it in a state where it is taken, the surfaces will stick together (blocking), and the hard coat layer surface is likely to be damaged, and the curl due to curing shrinkage is particularly large. As a result, it was difficult to obtain an air layer between the films, and the films were more easily blocked. This has led to a decline in product value and productivity, and an immediate solution has been desired.

As blocking prevention, the technique of the vinylidene chloride resin-type aqueous coating agent containing hydrophilic inorganic powder is known, for example (for example, refer patent document 1 and patent document 2). However, the antiblocking effect of the film having the high hardness hard coat layer was not sufficient.
JP-A-5-132645 JP 9-291250 A

  Accordingly, an object of the present invention is to provide a hard coat film having high hardness and excellent flatness in which blocking due to film tightening is suppressed, and a method for producing the hard coat film.

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

  1. In a hard coat film having a hard coat layer on a transparent film substrate, the thickness of the hard coat layer is 8 μm or more and 40 μm or less, and the transparent film substrate is represented by the following general formula (1) or (2 A hard coat film comprising a cellulose ester resin having at least one repeating unit represented by the formula:

[In formula, A and B represent a C1-C12 bivalent hydrocarbon group or a C1-C12 bivalent hydrocarbon group substituted by the hydroxyl group. However, A and B may be the same or different. ]
2. 2. The hard coat film as described in 1 above, wherein the transparent film base material contains a thermoplastic acrylic resin, and the thermoplastic acrylic resin is contained in an amount of 10 parts by mass or more based on 100 parts by mass of the cellulose ester resin.

  3. 2. The hard coat film according to 1, wherein the transparent film substrate contains a thermoplastic acrylic resin, and the thermoplastic acrylic resin is contained in an amount of 50 parts by mass or more based on 100 parts by mass of the cellulose ester resin.

  4). 4. The hard coat film as described in any one of 1 to 3 above, wherein the hard coat layer contains reactive silica particles (Xa) surface-treated with an organic compound having a polymerizable unsaturated group. .

5). The Martens hardness of the hard coat layer (HMS) is, 400 N / mm ² or more, the hard coating film according to any one of the 1 to 4, characterized in that there at 800 N / mm ² or less.

  6). 6. The hard coat film according to any one of 1 to 5, wherein the transparent film substrate has a thickness of 10 μm or more and 30 μm or less.

  7). In the formation of the hard coat layer of the hard coat film of any one of said 1-6, it comprises the process of heat-processing after light irradiation, The manufacturing method of the hard coat film characterized by the above-mentioned.

  8). 8. The method for producing a hard coat film as described in 7 above, wherein in the heat treatment step, the hard coat film is tensioned at 300 N to 500 N / m in the conveyance direction or the width direction.

  9. A polarizing plate characterized by using the hard coat film described in any one of items 1 to 6 on one side.

  10. 10. A display device using the polarizing plate as described in 9 above.

  According to the present invention, it is possible to provide a hard coat film having high hardness and excellent flatness in which blocking due to tightening of the film is suppressed, and a method for producing the hard coat film. Moreover, a polarizing plate and a display device using the hard coat film can be provided.

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

  The hard coat film of the present invention is a hard coat film having a hard coat layer on a transparent film substrate, the film thickness of the hard coat layer is 8 μm or more and 40 μm or less, and the transparent film substrate is It contains a cellulose ester resin having at least one repeating unit represented by the general formula (1) or (2).

  In the present invention, it is likely to occur when the hard coat layer thickness (dry film thickness) is increased (8 μm or more and 40 μm or less) in order to form a hard hard coat layer. It has been found that blocking can be remarkably suppressed by providing the hard coat layer on a transparent film using the cellulose ester resin having the specific structure, and the present invention has been achieved.

  Hereinafter, the hard coat layer which is one of the features of the present invention will be described.

<Hard coat layer>
In the present invention, the film thickness (dry film thickness) of the hard coat layer is 8 μm or more and 40 μm or less, preferably 14 μm or more and 26 μm or less from the viewpoint of exhibiting high hardness. By setting the film thickness within the above range, the surface hardness, blocking resistance, and flatness are all excellent. When the film thickness is thinner than 8 μm, it is impossible to obtain both high hardness and blocking resistance, which are the effects of the present invention. On the other hand, if the film thickness is larger than 40 μm, it is difficult to maintain the flatness of the hard coat layer, and the quality as a protective film of the image display device cannot be obtained.

  High hardness is desired because it is less likely to be scratched during use on the surface of a display device such as an LCD or in the polarizing plate forming process, and the high hardness in the present invention means that the pencil hardness, which is an index of hardness, is 3H or more. More preferably, it is 4H or more.

  For the pencil hardness, the prepared hard coat film is conditioned at a temperature of 23 ° C. and a relative humidity of 55% for 2 hours or more, and then using a test pencil specified by JIS S 6006, the pencil hardness specified by JIS K 5400. It is the value measured according to the evaluation method.

Moreover, Martens hardness of the hard coat (HMS) is, 400 N / mm ² or more, and preferably 800 N / mm ² or less. By adjusting the Martens hardness within this range, the surface hardness is excellent, and the object effect of the present invention is more effectively exhibited.

  Martens hardness (Vickers hardness) is a microhardness meter using a Vickers indenter and a triangular pyramid indenter whose angle between ridges is 115 degrees. The hard coat surface of the film is approximately 1 / th of the film thickness of the hard coat layer. In the load test force-indentation depth curve when the indenter is pushed down to a thickness of 10, the indentation from the 50% value to the 90% value of the maximum load test force (Fmax) obtained from the load test force-indentation depth curve From the slope (m) in which the depth is proportional to the square root of the load test force, it is a value defined by the following formula.

1HMs = 1 / (26.4m ² )
Next, the resin binder that forms the hard coat layer will be described. As the resin binder, an active energy ray curable resin is preferable. The active energy ray-curable resin refers to a resin that is cured through a crosslinking reaction or the like by irradiation with active rays such as ultraviolet rays or electron beams. As the active energy ray curable resin, a component containing a monomer having an ethylenically unsaturated double bond is preferably used, and the active energy ray curable resin layer is cured by irradiation with an active ray such as an ultraviolet ray or an electron beam. It is formed. Typical examples of the active energy ray curable resin include an ultraviolet curable resin and an electron beam curable resin. Particularly, the ultraviolet curable resin is excellent in mechanical film strength (abrasion resistance, pencil hardness). preferable.

  As the ultraviolet curable resin, a polyfunctional acrylate is preferable. The polyfunctional acrylate is preferably selected from the group consisting of pentaerythritol polyfunctional acrylate, dipentaerythritol polyfunctional acrylate, pentaerythritol polyfunctional methacrylate, and dipentaerythritol polyfunctional methacrylate. Here, the polyfunctional acrylate is a compound having two or more acryloyloxy groups and / or methacryloyloxy groups in the molecule.

  Examples of the polyfunctional acrylate monomer include ethylene glycol diacrylate, diethylene glycol diacrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, trimethylolpropane triacrylate, trimethylolethane triacrylate, and tetramethylolmethane triacrylate. , Tetramethylolmethane tetraacrylate, pentaglycerol triacrylate, pentaerythritol diacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, glycerin triacrylate, dipentaerythritol triacrylate, dipentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, dipentaerythritol Ritolol hexaacrylate, tris (acryloyloxyethyl) isocyanurate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, 1,6-hexanediol dimethacrylate, neopentyl glycol dimethacrylate, trimethylolpropane trimethacrylate, trimethylolethane trimethacrylate, Tetramethylol methane trimethacrylate, tetramethylol methane tetramethacrylate, pentaglycerol trimethacrylate, pentaerythritol dimethacrylate, pentaerythritol trimethacrylate, pentaerythritol tetramethacrylate, glycerol trimethacrylate, dipentaerythritol trimethacrylate, dipentaerythritol tetramethacrylate Acrylate, dipentaerythritol penta methacrylate, dipentaerythritol hexa methacrylate, isobornyl acrylate and the like preferably. These compounds are used alone or in admixture of two or more. Moreover, oligomers, such as a dimer and a trimer of the said monomer, may be sufficient. In the hard coat layer forming composition (hereinafter also referred to as a hard coat layer coating solution), the amount of the energy active ray curable resin added is preferably 15% by mass or more and less than 70% by mass in the solid content.

  The hard coat layer preferably contains a photopolymerization initiator in order to accelerate the curing of the energy active ray curable resin. The amount of the photopolymerization initiator is preferably a mass ratio of photopolymerization initiator; energy active ray curable resin = 20: 100 to 0.01: 100.

  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.

  For the hard coat layer, a binder such as a thermoplastic resin, a thermosetting resin, or a hydrophilic resin such as gelatin can also be used. Further, the hard coat layer may contain particles of an inorganic compound or an organic compound in order to adjust slipperiness and refractive index.

  Inorganic particles used for 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, calcined kaolin And calcined calcium silicate, hydrated calcium silicate, aluminum silicate, magnesium silicate and calcium phosphate. In particular, silicon oxide, titanium oxide, aluminum oxide, zirconium oxide, magnesium oxide and the like are preferably used.

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

  The average particle diameter of these fine particle powders is preferably 0.01 to 5 μm, more preferably 0.1 to 5.0 μm, and particularly preferably 0.1 to 4.0 μm. Moreover, it is preferable to contain 2 or more types of microparticles | fine-particles from which a particle size differs. The ratio of the 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 curable resin composition.

  In the present invention, reactive silica particles (Xa) surface-treated with an organic compound having a polymerizable unsaturated group are included in the hard coat layer in order to better exhibit the intended effect after a more severe durability test. It is preferable. Hereinafter, the reactive silica particles (Xa) surface-treated with an organic compound having a polymerizable unsaturated group will be described.

<Silica particles>
Known silica particles can be used. Further, the shape may be spherical or irregular, and is not limited to ordinary colloidal silica, and may be hollow particles, porous particles, core / shell particles, or the like.

Moreover, the number average particle diameter of the silica particles determined by the dynamic light scattering method is preferably 30 nm or more, more preferably 30 to 200 nm, and particularly preferably 40 to 80 nm. If the number average particle diameter of the silica particles is less than 30 nm, the hardness of the cured film may be reduced. If it is greater than 200 nm, the stability of the liquid (precipitation, Is difficult to obtain. The silica particles are preferably colloidal silica having a pH of 2.0 to 6.5. The dispersion medium of silica particles is preferably water or an organic solvent. Examples of organic solvents include alcohols such as methanol, isopropyl alcohol, ethylene glycol, butanol, and ethylene glycol monopropyl ether; ketones such as methyl ethyl ketone and methyl isobutyl ketone; aromatic hydrocarbons such as toluene and xylene; dimethylformamide, dimethyl Examples include amides such as acetamide and N-methylpyrrolidone; esters such as ethyl acetate, butyl acetate and γ-butyrolactone; and organic solvents such as ethers such as tetrahydrofuran and 1,4-dioxane. Of these, alcohols and ketones are preferred. These organic solvents can be used alone or in combination of two or more as a dispersion medium. As a commercial item, Nissan Chemical Industries Co., Ltd. MEK-ST-L, IPA-ST-L, IPA-ST-ZL etc. can be mentioned as colloidal silica, for example.
<Organic compound having a polymerizable unsaturated group>
The reactive silica particles (Xa) are obtained by surface treatment with an organic compound having a polymerizable unsaturated group (hereinafter referred to as “organic compound (X)”). The organic compound (X) used for the production of the reactive silica particles (Xa) is a compound having a polymerizable unsaturated group, preferably an ethylenically unsaturated group, and further has a group represented by the following general formula (a). It is preferable that it is an organic compound to contain. Further, it includes a [—O—C (═O) —NH—] group, and further includes a [—O—C (═S) —NH—] group and a [—S—C (═O) —NH—] group. It is preferable that at least one of these is included. The organic compound is preferably a compound having a silanol group in the molecule or a compound that generates a silanol group by hydrolysis.

[In General Formula (a), U represents NH, O (oxygen atom) or S (sulfur atom), and V represents O or S. ]
[1] Ethylenically unsaturated group Although there is no restriction | limiting in particular as an ethylenically unsaturated group contained in organic compound (X), For example, an acryloyl group, a methacryloyl group, and a vinyl group can be mentioned as a suitable example.

This ethylenically unsaturated group is a structural unit that undergoes addition polymerization with active radical species.
[2] The group represented by the general formula (a) The group [—UC (═V) —NH—] represented by the formula (a) contained in the organic compound is specifically represented by [—O—C. (═O) —NH—], [—O—C (═S) —NH—], [—S—C (═O) —NH—], [—NH—C (═O) —NH—]. , [—NH—C (═S) —NH—], and [—S—C (═S) —NH—]. These groups can be used individually by 1 type or in combination of 2 or more types. Among them, from the viewpoint of thermal stability, [—O—C (═O) —NH—] group, [—O—C (═S) —NH—] group and [—S—C (═O) — It is preferable to use in combination with at least one of the NH-] groups.

The group [—UC— (V) —NH—] represented by the formula (a) generates an appropriate cohesive force due to hydrogen bonding between molecules, and has excellent mechanical strength and group when cured. Excellent adhesion to materials and adjacent layers.
[3] Silanol groups or compounds that generate silanol groups by hydrolysis Examples of compounds that generate silanol groups include compounds in which an alkoxy group, aryloxy group, acetoxy group, amino group, halogen atom, or the like is bonded to a silicon atom. However, a compound in which an alkoxy group or an aryloxy group is bonded to a silicon atom, that is, an alkoxysilyl group-containing compound or an aryloxysilyl group-containing compound is preferable.
[4] Preferred embodiment As a preferred specific example, for example, a compound represented by the following general formula (b) can be mentioned.

In the general formula (b), R ²¹ and R ²² may be the same or different, and are a hydrogen atom, an alkyl group having 1 to 8 carbon atoms or an aryl group, for example, methyl, ethyl, propyl, butyl, octyl , Phenyl, xylyl group and the like. Here, j is an integer of 1 to 3.

Examples of the group represented by [(R ²¹ O) _j R ²² _3-j Si—] include a trimethoxysilyl group, a triethoxysilyl group, a triphenoxysilyl group, a methyldimethoxysilyl group, and a dimethylmethoxysilyl group. Can be mentioned. Of these groups, a trimethoxysilyl group or a triethoxysilyl group is preferable.

R ²³ is a divalent organic group having an aliphatic or aromatic structure having 1 to 12 carbon atoms, and may include a chain, branched, or cyclic structure. Specific examples include methylene, ethylene, propylene, butylene, hexamethylene, cyclohexylene, phenylene, xylylene, dodecamethylene and the like.

R ²⁴ is a divalent organic group, and is usually selected from divalent organic groups having a molecular weight of 14 to 10,000, preferably a molecular weight of 76 to 500. Specific examples include a chain polyalkylene group such as hexamethylene, octamethylene, and dodecamethylene; an alicyclic or polycyclic divalent organic group such as cyclohexylene and norbornylene; and 2 such as phenylene, naphthylene, biphenylene, and polyphenylene. Valent aromatic group; and these alkyl group-substituted and aryl group-substituted products. These divalent organic groups may contain an atomic group containing an element other than carbon and hydrogen atoms, and may contain a polyether bond, a polyester bond, a polyamide bond, and a polycarbonate bond.

R ²⁵ is a (k + 1) -valent organic group, and is preferably selected from a chain, branched or cyclic saturated hydrocarbon group and unsaturated hydrocarbon group.

  Z represents a monovalent organic group having a polymerizable unsaturated group in the molecule that undergoes an intermolecular crosslinking reaction in the presence of an active radical species. K is preferably an integer of 1 to 20, more preferably an integer of 1 to 10, and particularly preferably an integer of 1 to 5.

  Specific examples of the compound represented by the general formula (b) include compounds represented by the following (b-1) or the following (b-2).

[In (b-1) and (b-2), “Acryl” represents an acryloyl group. “Me” represents a methyl group. ]
For the synthesis of the organic compound (X), for example, the method described in JP-A-9-100111 can be used. Preferably, mercaptopropyltrimethoxysilane and isophorone diisocyanate are mixed in the presence of dibutyltin dilaurate and reacted at 60 to 70 ° C. for several hours, then pentaerythritol triacrylate is added, and further at 60 to 70 ° C. for several hours. Produced by reacting to some extent.

<(Xa) reactive silica particles>
The organic compound (X) is mixed with silica particles, hydrolyzed, and bonded together.

  The binding amount of the organic compound (X) to the silica particles is preferably 0.01% by mass or more, more preferably 0.1% by mass or more, based on 100% by mass of the reactive silica particles (Xa). Especially preferably, it is 1 mass% or more. Within the above range, the dispersibility is excellent, and the mechanical strength of the obtained cured product is also excellent.

  Moreover, the compounding ratio of the silica particles in the raw material during the production of the reactive silica particles (Xa) is preferably 5 to 99% by mass, and more preferably 10 to 98% by mass. The content of the silica particles constituting the reactive silica particles (Xa) is preferably 65 to 95% by mass.

  The content of the reactive silica particles (Xa) in the hard coat layer coating composition is preferably 5 to 80% by mass, and preferably 10 to 80% by mass when the total solid content in the composition is 100% by mass. % Is more preferable. By using it in the ratio of this range, it exists stably in a composition and it is easy to exhibit the target effect of this invention.

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

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

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

  Further, in the antiglare hard coat layer, an uneven shape may be formed on the hard coat surface by embossing with a roll or a master.

  The hard coat layer may contain the above-described fluorine compound or silicone compound. Moreover, you may contain the surfactant shown below. Specifically, Kao Corporation make: Emulgen 102KG (6.3), Emulgen 103 (8.1), Emulgen 104P (9.6), Emulgen 105 (9.7), Emulgen 106 (10.5), Emulgen 108 (12.1), Emulgen 109P (13.6), Emulgen 120 (15.3), Emulgen 123P (16.9), Emulgen 147 (16.3), Emulgen 210P (10.7), Emulgen 220 (14.2), Emulgen 306P (9.4), Emulgen 320P (13.9), Emulgen 404 (8.8), Emulgen 408 (10.0), Emulgen 409PV (12.0), Emulgen 420 (13 .6), Emulgen 430 (16.2), Emulgen 705 (10.5), Emulgen 707 (12.1), Margen 709 (13.3), Emulgen 1108 (13.5), Emulgen 1118S-70 (16.4), Emulgen 1135S-70 (17.9), Emulgen 2020G-HA (13.0), Emulgen 2025G (15 .7), Emulgen LS-106 (12.5), Emulgen LS-110 (13.4), Emulgen LS-114 (14.0), Emulgen MS-110 (12.7), Emulgen A-60 (12) .8), Emulgen A-90 (14.5), Emulgen A-500 (18.0), Emulgen B-66 (13.2), Latemul PD-420 (12.6), Latemulu PD-430 (14 .4), Latemul PD-430S (14.4), Latemul PD-450 (16.2), Rheodor SP-L10 (8.6), Leo SP-P10 (6.7), Rhedol SP-S10V (4.7), Rhedol SP-S20 (4.4), Rhedol SP-O10V (4.3), Rhedol Super SP-L10 (8. 6), Rheodor AS10V (4.7), Rheodor AO-10V (4.3), Rheodor AO-15V (3.7), Emazole L-10V (8.6), Emazole P-10V (6.7) , Emazole S-10V (4.7), Emazole O-10V (4.3), Rhedol TW-L120 (16.7), Rhedol TW-L106 (13.3), Rhedol TW-P120 (15.6) , Rhedol TW-S120V (14.9), Rheodor TW-S106V (9.6), Rhedol TW-S320V (10.5), Rhedol TW-O120V (1 5.0), Rheodor TW-O106V (10.0), Rheodor TW-O320V (11.0), Rheodor Super TW-L120 (16.7), Rheodor 430V (10.5), Rheodor 440V (11. 8), Rhedol 460V (13.8), Rhedol MS-60 (3.5), Rhedol MS-165V (11.0), Excel T-95 (3.8), Excel VS-95 (3.8) , Excel O-95R (3.5), Excel 200 (3.5), Excel 122V (3.5), Emanon 1112 (13.7), Emanon 4110 (11.6), Emanon CH-25 (10. 7), Emanon CH-40 (12.5), Emanon CH-60 (K) (14.0), Emanon CH-80 (15.0), Amite 102 ( .3), Amit 105 (9.8), Amit 105A (10.8), Amit 302 (5.1), Amit 320 (15.4), Aminone PK-02S (5.5), Aminone L-02 (5.8), manufactured by Nissin Chemical Industry Co., Ltd .: Surfinol 104E (4), Surfinol 104H (4), Surfinol 104A (4), Surfinol 104BC (4), Surfinol 104DPM (4), Surfy Nord 104PA (4), Surfinol 104PG-50 (4), Surfinol 104S (4), Surfinol 420 (4), Surfinol 440 (8), Surfinol 465 (13), Surfinol 485 (17), Surfinol SE (6), Surfinol SE-F (6), Surfinol 61 (6), Sir Inol 604 (8), Surfinol 2502 (8), Surfinol 82 (4), Surfinol DF110D (3), Surfinol CT111 (8-11), Surfinol CT121 (11-15), Surfinol CT136 (13 ), Surfinol TG (9), Surfinol GA (13), Orphine STG (9-10), Orphin E1004 (7-9), Orphin E1010 (13-14), Shin-Etsu Chemical Co., Ltd .: X-22 -4272 (7), X-22-6266 (8), KF-351 (12), KF-352 (7), KF-353 (10), KF-354L (16), KF-355A (12), KF-615A (10), KF-945 (4), KF-618 (11), KF-6011 (12), KF-601 5 (4), KF-6004 (5), and the like. Figures in parentheses indicate HLB values. The HLB value is Hydrophile-Lipophile-Balance, hydrophilic-lipophilic-balance, and is a value indicating the hydrophilicity or lipophilicity of a compound. The smaller the HLB value, the higher the lipophilicity, and the higher the value, the higher the hydrophilicity.

  The fluorine compound, silicone compound and surfactant have a mass ratio of the fluorine compound, silicone compound and surfactant: active light curable resin = 0.05: 100-5. Use at 00: 100 exists stably in the hard coat layer forming composition and in the hard coat layer.

  The hard coat layer further has a vinyl group and a carboxyl group in the side chain of the polyurethane resin as a curing aid, has a weight average molecular weight of 10,000 to 30,000, and a double bond equivalent of 500 to 2,000. An acrylic polymer having a vinyl group in a polymer or a side chain of the polymer, having a weight average molecular weight (Mw) of 10,000 or more and 100,000 or less, a double bond equivalent of 1,000 or less, and a polymer Tg of −50 ° C. or more and 120 ° C. or less, Other functional thiol compounds may be included. Examples of other functional thiol compounds include 1,4-bis (3-mercaptobutyryloxy) butane, pentaerythritol tetrakis (3-mercaptobutyrate), 1,3,5-tris (3-mercaptobutyloxyethyl)- 1,3,5-triazine-2,4,6 (1H, 3H, 5H) -trione and the like. Commercially available products include Showa Denko Co., Ltd., trade name Karenz MT series, and the like.

  Moreover, you may contain a fluorine-acrylic copolymer resin. The fluorine-acrylic copolymer resin is a copolymer resin composed of a fluorine monomer and an acrylic monomer, and a block copolymer composed of a fluorine monomer segment and an acrylic monomer segment is particularly preferable. The molecular weight of the fluorine-acrylic copolymer resin is 5,000 to 1,000,000 in terms of number average molecular weight, preferably 10,000 to 300,000, and more preferably 10,000 to 100,000. In the production of the fluorine-acrylic copolymer resin, polymeric peroxide was used as a polymerization initiator. It can be produced by a known production process (for example, Japanese Patent Publication No. 5-41668 and Japanese Patent Publication No. 5-59942). Polymeric peroxide is a compound having two or more peroxy bonds in one molecule. As the polymer peroxide, one or more of various polymer peroxides described in JP-B-5-59942 can be used. As a commercial item of fluorine-acrylic copolymer resin, the brand name of Nippon Oil & Fat Co., Ltd. Modiper F-200, Modiper F-600, Modiper F-2020, etc. are mentioned.

  Moreover, it is preferable that the refractive index of a hard-coat layer is adjusted to the range of 1.4-2.2 by 23 degreeC and wavelength 550nm measurement. The means for adjusting the refractive index can be achieved by adding metal oxide fine particles and the like. Metal oxide The metal oxide fine particles used preferably have a refractive index of 1.80 to 2.60, more preferably 1.85 to 2.50.

  The kind of metal oxide fine particles is not particularly limited, and Ti, Zr, Sn, Sb, Cu, Fe, Mn, Pb, Cd, As, Cr, Hg, Zn, Al, Mg, Si, P and S A metal oxide having at least one element selected from the group consisting of Al, In, Sn, Sb, Nb, a halogen element, Ta and the like is doped with a minute amount of atoms. May be. A mixture of these may also be used. In the present invention, at least one metal oxide fine particle selected from 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.

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

  The hard coat layer may contain a π-conjugated conductive polymer. The π-conjugated conductive polymer can be used as long as it is an organic polymer having a main chain composed of a π-conjugated system. Examples thereof include polythiophenes, polypyrroles, polyanilines, polyphenylenes, polyacetylenes, polyphenylene vinylenes, polyacenes, polythiophene vinylenes, and copolymers thereof. From the viewpoint of ease of polymerization and stability, polythiophenes, polyanilines, and polyacetylenes are preferable.

  The π-conjugated conductive polymer can provide sufficient conductivity and solubility in a binder resin even if it is not substituted, but in order to further improve conductivity and solubility, an alkyl group, a carboxy group, a sulfo group, an alkoxy group. A functional group such as a group, a hydroxy group, or a cyano group may be introduced.

Moreover, you may contain an ionic compound. The ionic compounds, imidazolium, pyridinium-based, alicyclic amine-based, aliphatic amine, cations and _BF ⁴ aliphatic phosphonium -, PF ₆ ^- inorganic ion system such, _CF 3 SO ₂ ^- , (CF ₃ SO ₂ ) ₂ N ⁻ , CF ₃ CO ₂ ^—, etc. Examples of the ionic compound include anionic polymer compounds such as those described in JP-B-49-23828, JP-A-49-23827, and JP-A-47-28937, JP-B-55-734, and JP-A-50-54672. Ionene type polymer having a dissociating group in the main chain, as shown in JP-B-59-14735, JP-B-57-18175, JP-B-57-18176, 57-56059, etc. No. 57-15376, No. 53-45231, No. 55-145783, No. 55-65950, No. 55-67746, No. 57-11342, No. 57-19735, No. 58-56858. No., JP-A 61-27853, 62-9346, and a cationic pendant type having a cationic dissociation group in the side chain Rimmer, etc. can be mentioned. It is also desirable to contain an ionene conductive polymer or a quaternary ammonium cation conductive polymer resin (for example, P-1 shown below) having intermolecular crosslinking described in JP-A-9-203810. The polymer compounds described above are generally in the particle size range of about 0.05 μm to 0.5 μm, preferably in the range of 0.05 μm to 0.2 μm. The ratio of the polymer to the binder is preferably 10 to 400 parts by mass of the binder with respect to 100 parts by mass of the polymer, particularly preferably 100 parts by mass of the binder with respect to 100 parts by mass of the polymer. -200 parts by mass.

  In addition, as a color correction filter for various display elements, a color tone adjusting agent (dye or pigment, etc.) having a color tone adjusting function, an electromagnetic wave blocking agent, an infrared absorber, or the like may be included.

(Coating process)
In the formation of the hard coat layer, since the effects of the present invention can be easily obtained, the hard coat layer is preferably subjected to light irradiation after coating and drying and further subjected to a heat treatment.

  An example of the heat treatment step is as shown in FIG. In addition, the heat treatment step needs to be performed in a place where the temperature and humidity can be adjusted, and is preferably performed in a clean room without dust.

  A preferable temperature for the heat treatment is 80 ° C. or higher, more preferably 120 ° C. or higher, from the viewpoint that the target effect is better exhibited. Further, the heat treatment time is preferably 20 minutes or less. Even if the heat treatment is carried out for a time longer than 20 minutes, the objective effect obtained better is not changed, and the film tends to be deteriorated in appearance such as discoloration or deformation due to heat.

  The heat treatment time here refers to a time during which the temperature is kept constant at a desired temperature, and does not include the time when the temperature is raised and the time when the temperature is lowered.

  The temperature to be held is preferably in the range of ± 5 ° C. of the set temperature. There may be a plurality of heat treatment steps. In that case, it may be designed so that each temperature can be changed.

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

At that time, it is also preferable to send cooling air from the air cooling air vent 6b to adjust the temperature of the actinic ray irradiating unit, and N ₂ gas is supplied from the N ₂ supply chamber to promote hardening of the hard coat layer. It is also preferable to do.

As examples of the light irradiation lamp, a low pressure mercury lamp, a medium pressure mercury lamp, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a carbon arc lamp, a metal halide lamp, a xenon lamp, or the like can be used. These light sources are preferably air-cooled or water-cooled. The irradiation conditions vary depending on individual lamps, the dose of active ray is preferably a ^{50mJ / cm 2 ~1J / cm 2} , particularly preferably 50 to 500 mJ / cm ^2. Further, it is preferable to reduce the oxygen concentration to 0.01% to 5% by nitrogen purge in the irradiated portion.

  When irradiating actinic radiation, it is preferably performed while applying tension in the film transport direction, and more preferably while applying tension in the width direction. The tension to be applied is preferably 30 to 500 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 with further excellent flatness. The width tension applying method is not particularly limited, and may be a free span, a back roll or the like. Moreover, the method of providing tension | tensile_strength using a width control apparatus in the width direction is also effective, Preferably it is extending | stretching at 3.0% or less, More preferably, it is 0.05%-1.0%.

  Next, after the light irradiation, heat treatment is performed in the heating zone 7. In the heating zone 7, the long film Y is heated at a predetermined temperature for a predetermined time by the transport rollers 2 arranged above and below.

  In the heat treatment step, it is preferably performed while applying a tension in the film transport direction or the width direction, and the applied tension is preferably 50 to 500 N / m, more preferably 300 to 500 N / m. At 300 to 500 N / m, the objective effect of the present invention is better exhibited after a more severe durability test. When it exceeds 500 N / m, it becomes difficult to maintain the flatness of the film. The width tension applying method is not particularly limited, and may be a free span, a back roll or the like. Moreover, the method of providing tension | tensile_strength using a width control apparatus in the width direction is also effective, Preferably it is extending | stretching 3.0% or less, More preferably, it is 0.05%-1.0% extending | stretching.

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

  As shown in FIG. 2, the heat treatment may be performed by applying a roll of the hard coat film wound on the movable carriage 12 after the application, drying, and light irradiation, and performing the heat treatment in the heat treatment chamber A.

  In the heat treatment A, it is preferable to gradually increase or decrease the temperature in order to prevent a temperature difference between the inside and outside of the roll of the film roll due to a rapid temperature increase and avoid wrinkles and the like near the winding core. . Specifically, the rate of temperature increase and the rate of temperature decrease are preferably 0.3 to 5 ° C./hour.

  Moreover, in order to prevent blocking and to keep a winding form favorable, it is preferable to give a knurling process. The knurling process should just be formed in the at least one surface of the film, and may be formed in both surfaces. The thickness of the knurling part is preferably larger than the film thickness of the hard coat layer, and the thickness of the knurling part is preferably in the range of 5 to 30 μm. Preferably it is the range of 10-25 micrometers.

  In addition, as the winding core when winding the hard coat film in a roll shape, any material may be used as long as it is a cylindrical core, preferably a hollow plastic core, and a plastic material As long as it is a heat-resistant plastic that can withstand the heat treatment temperature, any resin such as phenol resin, xylene resin, melamine resin, polyester resin, and epoxy resin can be used. A thermosetting resin reinforced with a filler such as glass fiber is preferred. The number of windings on these winding cores is preferably 100 windings or more, more preferably 500 windings or more, and the winding thickness is preferably 5 cm or more. Moreover, when performing the said heat processing in the state which wound the hard coat film wound up in roll shape, you may rotate this 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 also preferable to perform the roll rewinding once or more during the heating period.

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

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

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

  As the heating means in the heat treatment step, hot air blowing, contact heat transfer using a heating roll, induction heating using a microwave, radiant heat heating using an infrared heater, or the like can be used. As the infrared heater, an electric, gas, oil or steam far infrared ceramic heater can be used. A commercially available infrared heater (for example, manufactured by Noritake Company Limited) may be used. An oil-type or steam-type infrared heater using oil or steam as the heat medium is preferable from the viewpoint of explosion prevention in an atmosphere in which an organic solvent coexists. Moreover, the film temperature and heating temperature at the time of a heating can be measured with the non-contact-type infrared thermometer generally marketed. Further, feedback control may be performed on the heating means in order to control the temperature range.

  As a coating method of these hard coat layers, it can be applied 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.

  It is preferable to apply with a wet film thickness of 0.1 to 100 μm on one surface of the base film using the coating method.

  The hard coat layer may be a single layer or a multilayer structure of two or more layers.

  The hard coat layer may be subjected to the following surface treatment. Examples of the surface treatment method include a cleaning method, an alkali saponification treatment method, a plasma treatment 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.

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

  Further, the alkali saponification treatment may be performed by applying an alkali solution to the hard coat layer surface. For example, the methods described in JP-A Nos. 2003-313326 and 2007-332253 may be used.

  Examples of the plasma treatment include flame plasma treatment, atmospheric pressure plasma treatment, and atmospheric pressure plasma treatment.

  As plasma treatment, plasma treatment techniques disclosed in Japanese Patent Application Laid-Open Nos. 2004-352777, 2004-352777, 2007-314707, and the like can also be referred to.

  Further, the pure water contact angle on the surface of the hard coat layer after the surface treatment is 60 ° or less because, for example, when a low refractive index layer is provided on the hard coat layer, the adhesion between the hard coat layer and the hard coat layer is improved. preferable. The contact angle can be measured based on JIS K 2396.

<Antireflection film>
The low refractive index layer may be laminated directly or via another layer on the hard coat layer according to the present invention to have an antireflection function. By having an antireflection function, an effect of improving the visibility when incorporated in an image display device can be obtained.

<Low refractive index layer>
A low refractive index layer means a layer lower than the refractive index of a film base material. A specific refractive index is preferably in the range of 1.20 to 1.45 at 23 ° C. and a wavelength of 550 nm. Further, the film thickness of the low refractive index layer is preferably 5 nm to 0.5 μm, more preferably 10 nm to 0.3 μm, and further preferably 30 nm to 0.2 μm, from the characteristics as an optical interference layer.

  Further, in addition to the low refractive index layer, an antireflection layer may be configured by further combining a high refractive index layer having a higher refractive index than the support. Further, a medium refractive index layer (a layer having a higher refractive index than the support and a lower refractive index than the high refractive index layer) may be laminated. Moreover, you may provide a backcoat layer in the film back surface.

  Specific examples of the layer structure of the antireflection film include the following, but are not limited thereto.

Transparent film / Hard coat layer / Medium refractive index layer / Low refractive index layer Transparent film / Hard coat layer / Medium refractive index layer / High refractive index layer / Low refractive index layer Transparent film / Hard coat layer / Low refractive index layer Transparent film / Hard coat layer / conductive layer / low refractive index layer Transparent film / hard coat layer / high refractive index layer (conductive layer) / low refractive index layer Transparent film / hard coat layer / antiglare layer / low refractive index layer Back coat layer / transparent film / hard coat layer / low refractive index layer Back coat layer / transparent film / hard coat layer / medium refractive index layer / low refractive index layer Back coat layer / transparent film / hard coat layer / antiglare layer / Low refractive index layer Back coat layer / Transparent film / Hard coat layer / Conductive layer / Low refractive index layer Back coat layer / Transparent film / Hard coat layer / High refractive index layer (conductive layer) / Low refractive index layer Low The composition for forming a refractive layer may contain at least one kind of particles having an outer shell layer and porous or hollow inside as silica-based fine particles. The porous or hollow particles are preferably hollow silica-based fine particles.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

  As a method of adding to the low refractive index layer, for example, a solution obtained by adding a small amount of alkali or acid as a catalyst to a mixed solution of the tetraalkoxysilane, pure water, and alcohol is added to the dispersion of the hollow silica fine particles. The silicic acid polymer produced by hydrolyzing tetraalkoxysilane is deposited on the surface of the hollow silica fine particles. At this time, tetraalkoxysilane, alcohol, and catalyst may be simultaneously added to the dispersion. As the alkali catalyst, ammonia, an alkali metal hydroxide, or an amine can be used. As the acid catalyst, various inorganic acids and organic acids can be used. Silica-based fine particles may be those produced by the production method described in WO2007 / 099814.

(binder)
Moreover, it is preferable that the low refractive index layer contains the above-described cationic polymerizable compound as a binder from the viewpoint that the objective effect can be better exhibited. As the cationic polymerizable compound, the compounds described in the hard coat layer described above can be used. In addition, it is also preferable to use the above acid or photoacid generator as a compound that accelerates the polymerization of the cationic polymerizable compound. These acids and photoacid generators are preferably added in a proportion of 0.1 to 20 parts by mass, more preferably 0.5 to 15 parts by mass with respect to 100 parts by mass of the cationic polymerizable compound. From the viewpoint of stability in the composition for forming a low refractive index layer, polymerization reactivity, and the like.

  Moreover, you may use a radically polymerizable compound as a binder. As the radical polymerizable compound, the compounds described in the hard coat layer described above can be used.

  In order to accelerate curing of the radical polymerizable compound, it is preferable to use a photopolymerization initiator, and it is preferable to contain the photopolymerization initiator and the radical polymerizable compound in a mass ratio of 20: 100 to 0.01: 100.

  Furthermore, the fluorine substituted alkyl group containing silane compound represented by the said general formula (OSi-2) can also be contained.

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

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

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

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

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

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

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

The low refractive index layer may contain a silicon compound represented by CF ₃ (CF ₂ ) nCH ₂ CH ₂ Si (OR ₁ ) ₃ . (In the formula, R1 represents an alkyl group having 1 to 5 carbon atoms, and n represents an integer of 0 to 12.) Specific examples of the compound include trifluoropropyltrimethoxysilane and trifluoropropyl. Examples include triethoxysilane, tridecafluorooctyltrimethoxysilane, tridecafluorooctyltriethoxysilane, heptadecafluorodecyltrimethoxysilane, heptadecafluorodecyltriethoxysilane, and these are used alone or in combination of two or more. Can be used. _{It may} also contain H 2 NCONH (CH) mSi ( OR2) silicon compound in the terminal position represented by ₃ having a ureido group _(H 2 NCONH-). (In the formula, R2 represents an alkyl group having 1 to 5 carbon atoms, and m represents an integer of 1 to 5.) Specific compounds include γ-ureidopropyltrimethoxysilane and γ-ureido. Examples thereof include propyltriethoxysilane and γ-ureidopropyltripropoxysilane. Among these, γ-ureidopropyltrimethoxysilane, γ-ureidopropyltriethoxysilane, and the like are particularly preferable.

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

  In addition, examples of the binder include polyvinyl alcohol, polyoxyethylene, polymethyl methacrylate, polymethyl acrylate, fluoroacrylate, diacetyl cellulose, triacetyl cellulose, nitrocellulose, polyester, and alkyd resin.

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

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

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

  The low refractive index layer is coated with the above coating composition for forming the low refractive index layer using a known method such as a gravure coater, dip coater, reverse coater, wire bar coater, die coater, ink jet method, and the like. It is formed by drying and curing as necessary.

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

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

Here, the wavelength range of the irradiated light is not particularly limited, but light having a wavelength in the ultraviolet region is preferably used. Specifically, a low pressure mercury lamp, a medium pressure mercury lamp, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a carbon arc lamp, a metal halide lamp, a xenon lamp, or the like can be used. Irradiation conditions vary depending on each lamp, but the irradiation amount of active rays is usually 5 to 500 mJ / cm ² , preferably 5 to 150 mJ / cm ² , and particularly preferably 20 to 100 mJ / cm ² .

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

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

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

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

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

  The ratio of the metal oxide fine particles to be used and a binder such as an actinic ray curable resin to be described later varies depending on the kind of metal oxide fine particles, the particle size, etc. The latter one is preferable. The amount of the metal oxide fine particles used is preferably 5% by mass to 85% by mass, more preferably 10% by mass to 80% by mass, and most preferably 20% by mass to 75% by mass in the high refractive index layer. If the amount used is small, the desired refractive index and the effect of the present invention cannot be obtained, and if it is too large, the film strength deteriorates.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

  The addition amount of the radical polymerizable compound is preferably 15% by mass or more and less than 50% by mass in the solid content in the high refractive index composition.

  In order to accelerate curing of the radically polymerizable compound, it is preferable to contain a photopolymerization initiator. The addition amount of the photopolymerization initiator is preferably contained in a mass ratio of photopolymerization initiator: radically polymerizable compound = 3: 7 to 1: 9.

  As the photopolymerization initiator, specifically, the compounds described in the hard coat layer described above can be used.

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

  The high refractive index layer is obtained by applying the above composition to the hard coat layer surface with a wet film thickness of 0.1 to 100 μm using a gravure coater, dip coater, reverse coater, wire bar coater, die coater, spray coating, ink jet coating or the like. After coating, it is dried by heating, and cured as necessary. The content described in the low refractive index layer can be used in the curing step. The dry film thickness is adjusted to the above film thickness by adjusting the solid content concentration of the coating composition.

<Conductive layer>
The conductive layer can be provided on the transparent film substrate. For example, the conductive layer is provided between the hard coat layer and the antireflection layer or on the transparent film on the side opposite to the side on which the antireflection layer is provided. can do.

  The conductive layer imparts a function of preventing the first protective film from being charged during handling. Specifically, the π-conjugated conductive polymer and ionic polymer compound described above are applied to the hard coat layer. A metal oxide or the like is preferably used.

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

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

  An overcoat layer may be further provided on the conductive layer as the outermost surface layer, but the surface specific resistance value is measured by measuring the surface specific resistance value on the outermost surface layer on the side where the conductive layer is provided. It is defined as the surface specific resistance value of the conductive layer.

  Furthermore, examples of the ionic polymer compound include anionic polymer compounds such as those described in JP-B-49-23828, JP-A-49-23827, and JP-A-47-28937; JP-B-55-734, JP-A-50 Ionene type polymers having a dissociation group in the main chain as seen in JP-B-54672, JP-B-59-14735, JP-A-57-18175, JP-A-57-18176, JP-A-57-56059, etc .; No. -13223, No. 57-15376, No. 53-45231, No. 55-145578, No. 55-65950, No. 55-67746, No. 57-11342, No. 57-19735, No. 58 Cationic pendant having a cationic dissociation group in the side chain as seen in JP-A-56858, JP-A-61-27853, and 62-9346 Polymers; and the like. Among them, a quaternary ammonium cationic polymer having molecular crosslinking is particularly preferable, and a quaternary ammonium cationic polymer not containing chlorine ions and having molecular crosslinking is particularly preferably used from the viewpoint of environmental safety such as prevention of dioxin generation.

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

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

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

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

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

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

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

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

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

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

<Back coat layer>
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. In the hard coat film of the present invention, the dynamic friction coefficient on the back side of the actinic ray curable resin layer is preferably 0.9 or less, particularly preferably 0.1 to 0.9.

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

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

  It is preferable to apply these coating compositions on the surface of the hard coat film by using a gravure coater, dip coater, reverse coater, wire bar coater, die coater, spray coating, ink jet coating or the like with a wet film thickness of 1 to 100 μm. In particular, the thickness is 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. As the acrylic resin, the above-described compounds can be used for the conductive layer.

  As the resin used as the binder, it is preferable to use a blend of acetylated cellulose and acrylic resin such as cellulose diacetate and cellulose acetate prothionate, and the refractive index difference between the fine particles and the binder using fine particles made of acrylic resin. By setting the value to less than 0 to 0.02, a highly transparent back coat layer can be obtained.

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

(Reflectivity of antireflection layer)
The reflectance of the antireflection layer can be measured with a spectrophotometer or a spectrocolorimeter. At that time, after the surface on the measurement side of the sample is roughened, the light absorption treatment is performed by attaching a black spray, a black acrylic plate, etc., and then the reflected light in the visible light region (400 to 700 nm) is measured. To do.

  The lower the reflectivity, the better. However, the average value in the visible light region wavelength is 2.0% or less, and an external light antireflection function when used on the outermost surface of an image display device such as an LCD is suitably obtained. It is preferable from the point which is made. 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). Further, the range in which the distance Δxy of (x, y) = (0.31, 0.31) on the xy plane is 0.05 or less is preferable because it is closer to neutral with no color, and 0.03 or less is preferable. Further preferred. The color tone can be calculated from the refractive index of each layer in accordance with a conventional method in consideration of the reflectance and the color of reflected light.
<Cellulose ester resin having at least one repeating unit represented by formula (1) or (2)>
The cellulose ester resin having at least one repeating unit represented by formula (1) or (2), which is one of the features of the present invention constituting the transparent film, will be described.

  By using the cellulose ester resin having the specific structure as a film base material, film deformation hardly occurs and smoothness is maintained. Therefore, the desired effect is exhibited by combining with the above-described high hardness hard coat layer. The cellulose ester resin having at least one repeating unit represented by the following general formula (1) or (2) will be described in detail.

[In formula, A and B represent a C1-C12 bivalent hydrocarbon group or a C1-C12 bivalent hydrocarbon group substituted by the hydroxyl group. However, A and B may be the same or different. ]
It is a cellulose ester resin having at least one repeating unit represented by the general formula (1) or (2).

Specific examples of A are given below.
A-1-CH ₂ CH _{2-
A-2 -CH 2 CH 2 CH} 2 -
A-3 -CH = CH-

A-6 —CH ₂ C (CH ₃ ) ₂ —
Specific examples of B are given below.
B-1 _{-CH 2} CH 2 -
B-2-CH ₂ CH ₂ CH ₂ CH _2-

  The cellulose ester resin having a repeating unit represented by the general formula (1) or (2) is already partly by cellulose having an unsubstituted hydroxyl group or an acyl group such as an acetyl group, a propionyl group, a butyryl group, or a phthalyl group. Esterification reaction of polybasic acid or its anhydride with polyhydric alcohol or ring-opening polymerization of L-lactide, D-lactide, L-lactic acid, D- It can be obtained by carrying out self-condensation of lactic acid.

  Examples of the polybasic acid anhydride used in the esterification reaction include, but are not limited to, maleic anhydride, phthalic anhydride, and fumaric anhydride.

  Examples of the polyhydric alcohol that can be used in the esterification reaction include glycerin, ethylene glycol, and propylene glycol, but are not particularly limited.

  As the catalyst used for the esterification reaction, the reaction can be carried out without a catalyst, but a known Lewis acid catalyst or the like can be used. Examples of catalysts that can be used include metals such as tin, zinc, titanium, bismuth, zirconium, germanium, antimony, sodium, potassium, and aluminum, and derivatives thereof. Particularly, the derivatives include metal organic compounds, carbonates, oxides, halides. Is preferred. Specific examples include octyl tin, tin chloride, zinc chloride, titanium chloride, alkoxy titanium, germanium oxide, zirconium oxide, antimony trioxide, and alkyl aluminum. Moreover, an acid catalyst typified by p-toluenesulfonic acid can also be used as the catalyst. Moreover, in order to accelerate | stimulate the dehydration reaction of carboxylic acid and alcohol, you may add well-known compounds, such as carbodiimide and dimethylaminopyridine.

  Such a reaction may be a reaction in an organic solvent capable of dissolving cellulose ester and other compounds to be reacted, or a reaction using a batch kneader capable of heating and stirring while adding a shearing force. It may be by reaction using a uniaxial or biaxial extruder.

  The repeating unit represented by the general formula (1) or (2) can be appropriately contained in the range of 0.5 to 190% by mass with respect to cellulose.

  Although the substitution degree of this cellulose ester can be selected suitably, it is preferable that it is 2.2-3 from the point of thermoplasticity and heat workability.

  In the cellulose ester resin having at least one repeating unit represented by the general formula (1) or (2), when the hydrogen atom of the hydroxyl group of cellulose is a fatty acid ester with an aliphatic acyl group, the aliphatic acyl group is Specific examples thereof include 2 to 20 carbon atoms and include acetyl, propionyl, butyryl, isobutyryl, valeryl, pivaloyl, hexanoyl, octanoyl, lauroyl, stearoyl and the like.

  The polymerization degree of the cellulose ester resin having at least one repeating unit represented by the general formula (1) or (2) is not particularly limited, and is, for example, a viscosity average polymerization degree of 70 or more (for example, 80 to 800). It may be selected from the range of 100 to 500, preferably 110 to 400, and more preferably about 120 to 350.

The repeating unit represented by the general formula (1) or (2) is, for example, 80 to 10,000, preferably 100 to 5000, more preferably about 200 to 2000, particularly 300 to 1500, as the number average molecular weight of the portion. Usually, it may be less than 1000. In addition, the number average molecular weight of only the repeating unit which the said cellulose ester has was calculated | required by comparing with the GPC data which converted the cellulose ester before esterification reaction, and the cellulose ester after reaction into polystyrene, or < ¹ > H-NMR.

  An oligomer or polyester having a repeating unit represented by formula (1) or (2) as a side reaction when the repeating unit represented by formula (1) or (2) is introduced into cellulose or cellulose ester However, since these compounds act as plasticizers, they need not be completely removed by purification. If content is 30 mass% or less with respect to a cellulose ester, there will be little change in the property of a cellulose ester. From the viewpoint of plasticity, it is preferably 0.5 to 20% by mass. These oligomers and polyesters have a number average molecular weight of 300 to 10,000, and preferably 500 to 8,000 from the viewpoint of plasticity.

  Further, a graft copolymerized modified glucan derivative (modified cellulose derivative) described in JP-A-2008-197561 is also a cellulose ester resin having at least one repeating unit represented by the general formula (1) or (2) of the present invention. Can be used.

  Further, a transparent film containing a cellulose ester resin having at least one repeating unit represented by the general formula (1) or (2) (hereinafter simply referred to as a repeating unit represented by the general formula (1) or (2)) It is preferable that the cellulose ester film having) or simply the cellulose ester film) has the following characteristics.

Transmittance: 80% or more
0nm ≦ Ro ≦ 330nm
−100 nm ≦ Rt ≦ 340 nm
Ro = (nx−ny) × d
Rt = ((nx + ny) / 2−nz) × d
(Where nx is the refractive index in the slow axis direction in the plane of the cellulose ester film, ny is the refractive index in the direction perpendicular to the slow axis in the plane, nz is the refractive index in the thickness direction, and d is the refractive index in the thickness direction) (Represents the thickness (nm) of the cellulose ester film. The refractive index is measured at 590 nm.)
The refractive index can be obtained at a wavelength of 590 nm under an environment of 23 ° C. and 55% RH using, for example, KOBRA-21ADH (Oji Scientific Instruments). The content of the solvent is preferably 0.01% by mass or less.

  In addition, the film thickness of the cellulose ester film is preferably 100 μm or less from the viewpoint of handleability when used as an optical film and the ability to reduce the thickness of a liquid crystal display panel.

  In particular, in the case of a thin film having a cellulose ester film thickness of 30 μm or less, the effects of the present invention can be easily obtained, and it is preferably 10 μm or more from the practical point of view.

  The cellulose ester film has a length of 100 m to 9000 m, more preferably 1000 m to 7000 m, and a width of 1.2 m or more, and more preferably 1.4 to 4 m. The cellulose ester film is preferably roll-shaped. By making the length and width of the film within the above ranges and handling them in a roll shape, it is excellent in handleability and productivity, and the object effects of the present invention are easily exhibited.

The film containing a cellulose ester resin having at least one repeating unit represented by the general formula (1) or (2) preferably has few bright spot foreign substances. The bright spot foreign matter preferably has a bright spot diameter of 0.01 mm or more and 200 pieces / cm ² or less, more preferably 100 pieces / cm ² or less, and preferably 50 pieces / cm ² or less. 30 / cm ² or less, preferably 10 / cm ² or less, and most preferably none.

Moreover, it is preferable that it is 200 pieces / cm < ² > or less also about a bright spot of 0.005-0.01 mm or less, Furthermore, it is preferable that it is 100 pieces / cm < ² > or less, and it is 50 pieces / cm < ² > or less. The number is preferably 30 pieces / cm ² or less, more preferably 10 pieces / cm ² or less, and most preferably none.

  In the present invention, the transparent film contains a thermoplastic acrylic resin from the point of exhibiting the intended effect after a more severe durability test, and it is contained at 10 parts by mass or more with respect to 100 parts by mass of the cellulose ester resin. preferable. More preferably, it is contained at 50 parts by mass or more with respect to 100 parts by mass of the contained cellulose ester resin. Although there is no restriction | limiting in particular as an upper limit of addition amount, From a compatible point with a cellulose resin, it is preferable to contain at 2000 mass parts or less with respect to 100 mass parts of said cellulose-ester resins. Moreover, from the point which improves the transparency of a transparent film, it is necessary to contain an acrylic resin and a cellulose-ester resin in a compatible state.

  The thermoplastic acrylic resin includes a methacrylic resin. Although it does not restrict | limit especially as resin, What consists of 50-99 mass% of methyl methacrylate units and 1-50 mass% of other monomer units copolymerizable with this is preferable. Other monomers that can be copolymerized include alkyl methacrylates having 2 to 18 carbon atoms, alkyl acrylates having 1 to 18 carbon atoms, acrylic acid, methacrylic acid, and the like. Saturated acids, maleic acids, fumaric acids, unsaturated group-containing divalent carboxylic acids such as itaconic acid, aromatic vinyl compounds such as styrene and α-methylstyrene, α, β-unsaturated nitriles such as acrylonitrile and methacrylonitrile, Maleic anhydride, maleimide, N-substituted maleimide, glutaric anhydride and the like can be mentioned, and these can be used alone or in combination of two or more monomers.

  Among these, methyl acrylate, ethyl acrylate, n-propyl acrylate, n-butyl acrylate, s-butyl acrylate, 2-ethylhexyl acrylate, and the like are preferable from the viewpoint of thermal decomposition resistance and fluidity of the copolymer. n-Butyl acrylate is particularly preferably used.

  The thermoplastic acrylic resin preferably exhibits a weight average molecular weight (Mw) of 80,000 to 500,000, and more preferably within a range of 110,000 to 500,000, since the objective effects of the present invention are exhibited well.

  The weight average molecular weight of the acrylic resin can be measured by gel permeation chromatography. The measurement conditions are as follows.

Solvent: Methylene chloride Column: Shodex K806, K805, K803G (Used by connecting three Showa Denko Co., Ltd.)
Column temperature: 25 ° C
Sample concentration: 0.1% by mass
Detector: RI Model 504 (manufactured by GL Sciences)
Pump: L6000 (manufactured by Hitachi, Ltd.)
Flow rate: 1.0ml / min
Calibration curve: Standard polystyrene STK standard polystyrene (manufactured by Tosoh Corporation) Mw = 2,800,000-500 calibration curves with 13 samples were used. The 13 samples are preferably used at approximately equal intervals.

  There is no restriction | limiting in particular as a manufacturing method of an acrylic resin, You may use any well-known methods, such as suspension polymerization, emulsion polymerization, block polymerization, or solution polymerization. Here, as a polymerization initiator, a normal peroxide type and an azo type can be used, and a redox type can also be used. Regarding the polymerization temperature, suspension or emulsion polymerization may be performed at 30 to 100 ° C, and bulk or solution polymerization may be performed at 80 to 160 ° C. In order to control the reduced viscosity of the obtained copolymer, polymerization can be carried out using alkyl mercaptan or the like as a chain transfer agent.

  Commercial products can also be used. For example, Delpet 60N, 80N (Asahi Kasei Chemicals Co., Ltd.), Dialal BR52, BR80, BR83, BR85, BR88 (Mitsubishi Rayon Co., Ltd.), KT75 (Electrochemical Industry Co., Ltd.) and the like can be mentioned. . Two or more acrylic resins can be used in combination.

<Acrylic particles>
The transparent film may contain acrylic particles because the film is excellent in brittleness.

  Acrylic particles represent an acrylic component present in a particle state (also referred to as an incompatible state) in a film substrate containing the thermoplastic acrylic resin and the cellulose ester resin in a compatible state.

  The acrylic particles are obtained by, for example, collecting a predetermined amount of the prepared film base material, dissolving it in a solvent, stirring, and sufficiently dissolving and dispersing it. A PTFE membrane having a pore diameter less than the average particle diameter of the acrylic particles. It is preferable that the weight of the insoluble matter filtered and collected using a filter is 90% by mass or more of the acrylic particles added to the film substrate.

  The acrylic particles are not particularly limited, but are preferably acrylic particles having a layer structure of two or more layers, and particularly preferably the following multilayer structure acrylic granular composite.

  The multilayer structure acrylic granular composite is formed by laminating an innermost hard layer polymer, a cross-linked soft layer polymer exhibiting rubber elasticity, and an outermost hard layer polymer from the center to the outer periphery. This refers to a particulate acrylic polymer having a structure.

  That is, the multilayer structure acrylic granular composite is a multilayer structure acrylic granular composite comprising an innermost hard layer, a crosslinked soft layer, and an outermost hard layer from the central portion toward the outer peripheral portion. This three-layer core / shell structure multilayer structure acrylic granular composite is preferably used.

  The particle diameter of the acrylic particles is not particularly limited, but is preferably 10 nm or more and 1000 nm or less, more preferably 20 nm or more and 500 nm or less, and particularly 50 nm or more and 400 nm or less. Most preferred.

  Examples of commercially available acrylic particles include “Metablene” manufactured by Mitsubishi Rayon Co., “Kaneace” manufactured by Kaneka Chemical Co., Ltd., “Paraloid” manufactured by Kureha Chemical Co., Ltd., “Acryloid” manufactured by Rohm and Haas, “STAPHYLOID” manufactured by Kogyo Co., Ltd., “Parapet SA” manufactured by Kuraray Co., Ltd., Metabrene W-341 (C2) (manufactured by Mitsubishi Rayon Co., Ltd.), Chemisnow MR-2G (C3), MS-300X (C4) (Soken Chemical ( And the like).

  The acrylic fine particles are acrylic fine particles: thermoplastic acrylic resin and cellulose ester resin total mass = 0.5: 100 to the total mass of the thermoplastic acrylic resin and the cellulose ester resin constituting the transparent film. It is preferable to make it contain in the range of 30: 100, More preferably, it is the range of the total mass of acrylic fine particles: acrylic resin and cellulose-ester resin = 1.0: 100-15: 100.

<Additives>
The film containing a cellulose ester resin having at least one repeating unit represented by the general formula (1) or (2) is an acrylic polymer and at least one of at least one of a pyranose structure and a furanose structure, 12 to 12 It may contain at least one selected from the following sugar ester compounds obtained by esterifying all or part of the OH groups of the structure.

<Sugar ester compound>
Examples of the sugar ester compound include glucose, galactose, mannose, fructose, xylose, arabinose, lactose, sucrose, cellobiose, cellotriose, maltotriose, raffinose and the like, and those having both a furanose structure and a pyranose structure are particularly preferable. An example is sucrose.

  The sugar ester compound is one in which part or all of the hydroxyl groups of the sugar compound are esterified or a mixture thereof.

  The sugar ester compound is a compound obtained by condensing 1 or more and 12 or less of at least one pyranose structure or furanose structure represented by the following general formula (A). However, R11-R15, R21-R25 represents a C2-C22 acyl group or a hydrogen atom, m and n represent the integer of 0-12, respectively, and m + n represents the integer of 1-12.

R _{11 to} R ₁₅ and R _{21 to} R ₂₅ are preferably a benzoyl group or a hydrogen atom. The benzoyl group may further have a substituent R26 (p is 0 to 5), and examples thereof include an alkyl group, an alkenyl group, an alkoxyl group, and a phenyl group. Further, these alkyl groups, alkenyl groups, and phenyl groups are It may have a substituent. Oligosaccharides can also be produced by a similar method.

As a commercial item, monopet SB (Daiichi Kogyo Seiyaku Co., Ltd. product) etc. are mentioned, for example.
<Acrylic polymer>
An acrylic polymer may be added to a film containing a cellulose ester resin having at least one repeating unit represented by the general formula (1) or (2). Here, the acrylic polymer includes a methacrylic polymer. When an acrylic polymer is contained, it preferably exhibits negative birefringence in the stretching direction as a function, and the structure is not particularly limited, but is obtained by polymerizing an ethylenically unsaturated monomer. It is preferable that the polymer has a weight average molecular weight of 500 to 30,000. The acrylic polymer having a weight average molecular weight of 500 to 30,000 may be an acrylic polymer having an aromatic ring in the side chain or an acrylic polymer having a cyclohexyl group in the side chain.

  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.

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

  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.

  Examples of the acrylic polymer include an ethylenically unsaturated monomer Xa having no aromatic ring and a hydroxyl group in the molecule, an ethylenically unsaturated monomer Xb having no aromatic ring in the molecule and a hydroxyl group, and Xa and Xb. Polymer X having a weight average molecular weight of 2000 or more and 30000 or less obtained by copolymerization with a copolymerizable ethylenically unsaturated monomer, or ethylenically unsaturated monomer Ya having no aromatic ring and copolymerized with Ya The polymer Y is preferably a polymer Y having a weight average molecular weight of 500 or more and 3000 or less obtained by polymerizing a possible ethylenically unsaturated monomer.

[Polymer X, Polymer Y]
As a method for adjusting the Ro and Rt of the cellulose ester film with the repeating unit represented by the general formula (1) or (2), an ethylenically unsaturated monomer Xa having no aromatic ring and no hydroxyl group in the molecule, Weight average molecular weight 2000 or more and 30000 or less obtained by copolymerizing ethylenically unsaturated and nomeric Xb having a hydroxyl group and copolymerizable ethylenically unsaturated monomer excluding Xa and Xb High molecular weight polymer X, and more preferably, a weight average molecular weight obtained by polymerizing an ethylenically unsaturated monomer Ya having no aromatic ring and an ethylenically unsaturated monomer copolymerizable with Ya It is preferable to contain a polymer Y having a low molecular weight of 500 or more and 3000 or less.

  Polymer X can be copolymerized with ethylenically unsaturated monomer Xa having no aromatic ring and hydroxyl group in the molecule and ethylenically unsaturated monomer Xb having no aromatic ring in the molecule and having a hydroxyl group, excluding Xa and Xb It is a polymer having a weight average molecular weight of 2000 or more and 30000 or less obtained by copolymerization with an ethylenically unsaturated monomer.

  Preferably, Xa is an acrylic or methacrylic monomer having no aromatic ring and hydroxyl group in the molecule, and Xb is an acrylic or methacrylic monomer having no aromatic ring and having a hydroxyl group in the molecule.

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

Formula (X)
-[Xa] m- [Xb] n- [Xc] p-
In the general formula (X), Xa represents an ethylenically unsaturated monomer having no aromatic ring and hydroxyl group in the molecule, and Xb represents an ethylenically unsaturated monomer having no aromatic ring and having a hydroxyl group in the molecule. Xc represents a copolymerizable ethylenically unsaturated monomer excluding Xa and Xb. m, n, and p each represent a molar composition ratio. However, m ≠ 0 and m + n + p = 100.

  Furthermore, the polymer X is preferably 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 general formula (X-1), R1 and R3 each represent a hydrogen atom or a methyl group. R2 represents an alkyl group having 1 to 12 carbon atoms or a cycloalkyl group. R4 is _{-CH 2 -, - C 2 H} 4 - or _-C 3 _{H 6} - represents a. Xc _{is, [CH 2 -C (-R1)} (- CO 2 R2)] representing the a polymerizable monomer unit or _{[CH 2 -C (-R3) (} - - CO 2 R4-OH)]. m, n, and p represent a molar composition ratio. However, m ≠ 0 and m + n + p = 100.

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

  In X, the hydroxyl group means not only a hydroxyl group but also a group having an ethylene oxide chain. Examples of the ethylenically unsaturated monomer Xa having no aromatic ring and hydroxyl 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), etc. The thing changed into acid ester can be mentioned. Among these, methyl acrylate, ethyl acrylate, methyl methacrylate, ethyl methacrylate, and propyl methacrylate (i-, n-) are preferable.

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

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

  The molar composition ratio m: n of Xa and Xb 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 there are many X and molar composition ratios, compatibility with a cellulose ester will improve, but the retardation value Rt of a film thickness direction will become large. 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.

  The molecular weight of the high molecular weight polymer X is more preferably 5000 or more and 30000 or less, and still more preferably 8000 or more and 25000 or less.

  By setting the weight average molecular weight to 5,000 or more, it is preferable because advantages such as little dimensional change under high temperature and high humidity of the cellulose ester film having the repeating unit represented by the general formula (1) or (2) are obtained.

  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 are suppressed.

  The weight average molecular weight of the polymer X according to 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 from room temperature to 130 ° C., preferably from 50 ° C. to 100 ° C., but this temperature or the polymerization reaction time can be adjusted.

  In addition, a weight average molecular weight etc. can be calculated | required according to the above-mentioned method.

  The polymer Y is a polymer having a weight average molecular weight of 500 or more and 3000 or less obtained by polymerizing an ethylenically unsaturated monomer Ya having no aromatic ring. A weight average molecular weight of 500 or more is preferred because the residual monomer in 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 is represented by the following general formula (Y).

General formula (Y)
-[Ya] k- [Yb] q-
In the general formula (Y), Ya represents an ethylenically unsaturated monomer having no aromatic ring, and Yb represents an ethylenically unsaturated monomer copolymerizable with Ya. k and q each represent a molar composition ratio. However, k ≠ 0 and k + q = 100.

  The polymer Y is more preferably a polymer represented by the following general formula (Y-1).

General formula (Y-1)
_{- [CH 2 -C (-R5)} (- CO 2 R6)] k- [Yb] q-
In the general formula (Y-1), R5 represents a hydrogen atom or a methyl group, respectively. R6 represents an alkyl group having 1 to 12 carbon atoms or a cycloalkyl group. Yb represents a monomer unit copolymerizable with [CH ₂ —C (—R 5) (— CO ₂ R 6)]. k and q each represent a molar composition ratio. However, k ≠ 0 and k + q = 100.

Yb is a _{Ya [CH 2 -C (-R5)} (- CO 2 R6)] and is not particularly limited as long as it is copolymerizable ethylenically unsaturated monomers. Yb may be plural. k + q = 100, q is preferably 0-30.

  The ethylenically unsaturated monomer Ya constituting the polymer Y obtained by polymerizing the 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-), acrylic Acid heptyl (n-, i-), octyl acrylate (n-, i-), nonyl acrylate (n-, i-), myristyl acrylate (n-, i-), cyclohexyl acrylate, acrylic acid ( 2-ethylhexyl), 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 weight as uniform 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 using a chain transfer agent such as carbon tetrachloride, a method using a polymerization terminator such as benzoquinone and dinitrobenzene in addition to the polymerization initiator, and further disclosed in JP 2000-128911 or 2000-344823 Examples thereof include a method of bulk polymerization using a compound having one thiol group and a secondary hydroxyl group, or a polymerization catalyst in which the compound and an organometallic compound are used in combination, and any of them is preferably used.

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

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

  The hydroxyl value is measured in accordance with JIS K 0070 (1992). This hydroxyl value is defined as the number of mg of potassium hydroxide required to neutralize acetic acid bound to the sample 1 and acetylated and bound to the hydroxyl group.

  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
In the formula, B is the amount (ml) of 0.5 mol / L potassium hydroxide ethanol solution used for the blank test, C is the amount (ml) of 0.5 mol / L potassium hydroxide ethanol solution used for titration, f is a factor of a 0.5 mol / L potassium hydroxide ethanol solution, D is an acid value, and 28.05 is 1/2 of 1 mol amount 56.11 of potassium hydroxide.

  Both the above-mentioned polymer X and polymer Y are excellent in compatibility with a film containing a cellulose ester resin having at least one repeating unit represented by the general formula (1) or (2), and can be evaporated or volatilized. It has excellent productivity, good retention as a protective film for polarizing plates, low moisture permeability, and excellent dimensional stability.

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% = (mass of polymer X / mass of 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 (Xg + Yg) in the formula (i) is 10 to 35% by mass. If the polymer X and the polymer Y are 5 mass% or more as a total amount with respect to the total mass of the cellulose ester, the polymer X and the polymer Y have a sufficient effect for adjusting the retardation value Rt. The polymer X and the polymer Y are directly added and kneaded as a material constituting the melting described later.

  A film containing a cellulose ester resin having at least one repeating unit represented by the general formula (1) or (2) is a plasticizer that imparts processability to the film, an antioxidant that prevents deterioration of the film, You may contain additives, such as the ultraviolet absorber which provides an ultraviolet-absorbing function, the microparticles | fine-particles (mat | matte agent) which provide slipperiness to a film, and the retardation adjusting agent which adjusts the retardation of a film.

<Other additives>
As other additives, it is necessary to appropriately select a plasticizer.

<Plasticizer>
In production of a film containing a cellulose ester resin having at least one repeating unit represented by the general formula (1) or (2), it is preferable to contain at least one plasticizer in the film-forming material.

  The plasticizer can be used alone or in combination of two or more, but at least one is a polyhydric alcohol ester plasticizer having a molecular weight of 350 to 1500 having a structure in which an organic acid and a trivalent or higher alcohol are condensed. Is preferred.

  Other plasticizers that can be used are not particularly limited, but are preferably polyhydric alcohol ester plasticizers, aromatic-terminated polyester plasticizers, glycolate plasticizers, phthalate ester plasticizers, fatty acid esters. It is selected from system plasticizers, polymer plasticizers, sugar ester compounds and the like.

If the amount of the plasticizer used is less than 1% by mass with respect to the cellulose derivative, the effect of reducing the moisture permeability of the film is small, which is not preferred. -20 mass% is preferable. Hereinafter, preferred plasticizers will be described.
(Polyhydric ester plasticizer)
The polyhydric alcohol ester plasticizer is an ester of an organic acid and a polyhydric alcohol, and the organic acid is represented by the following general formula (3).

In the formula, R _{1 to} R ₅ represent a hydrogen atom or a cycloalkyl group, an aralkyl group, an alkoxy group, a cycloalkoxy group, an aryloxy group, an aralkyloxy group, an acyl group, a carbonyloxy group, an oxycarbonyl group, or an oxycarbonyloxy group. These may be further substituted. L represents a linking group and represents a substituted or unsubstituted alkylene group, an oxygen atom, or a direct bond.

The cycloalkyl group represented by R ₁ to R _5, preferably a cycloalkyl group having 3 to 8 carbon atoms, specifically cyclopropyl, cyclopentyl, groups such as cyclohexyl. These groups may be substituted, and preferred substituents include halogen atoms such as chlorine atom, bromine atom, fluorine atom, hydroxyl group, alkyl group, alkoxy group, cycloalkoxy group, aralkyl group (this phenyl group). The group may be further substituted with an alkyl group or a halogen atom), an alkenyl group such as a vinyl group or an allyl group, or a phenyl group (this phenyl group may be further substituted with an alkyl group or a halogen atom). Phenoxy group (this phenyl group may be further substituted by an alkyl group or a halogen atom), an acyl group having 2 to 8 carbon atoms such as an acetyl group or a propionyl group, an acetyloxy group, or a propionyloxy group. And an unsubstituted carbonyloxy group having 2 to 8 carbon atoms such as a group.

The aralkyl group represented by R _{1 to} R ₅ represents a group such as a benzyl group, a phenethyl group, and a γ-phenylpropyl group, and these groups may be substituted. Preferred substituents include The group which may be substituted with the said cycloalkyl group can be mentioned similarly.

Examples of the alkoxy group represented by R _{1 to} R ₅ include an alkoxy group having 1 to 8 carbon atoms, specifically, methoxy, ethoxy, n-propoxy, n-butoxy, n-octyloxy, isopropoxy. , Alkoxy groups such as isobutoxy, 2-ethylhexyloxy, or t-butoxy.

  These groups may be substituted, and preferred substituents include halogen atoms such as chlorine atom, bromine atom, fluorine atom, hydroxyl group, alkoxy group, cycloalkoxy group, aralkyl group (this phenyl group). May be substituted with an alkyl group or a halogen atom), an alkenyl group, a phenyl group (this phenyl group may be further substituted with an alkyl group or a halogen atom), an aryloxy group (for example, phenoxy) An acyl group such as an acetyl group or a propionyl group, or an aryl group such as an acetyloxy group or a propionyloxy group (the phenyl group may be further substituted with an alkyl group or a halogen atom). Arylcarbonyl groups such as unsubstituted acyloxy groups and benzoyloxy groups Shi group.

Examples of the cycloalkoxy group represented by R _{1 to} R ₅ include an unsubstituted cycloalkoxy group having 1 to 8 carbon atoms, specifically cyclopropyloxy, cyclopentyloxy, cyclohexyloxy. And the like.

  In addition, these groups may be substituted, and preferable examples thereof include the same groups that may be substituted with the cycloalkyl group.

Examples of the aryloxy group represented by R _{1 to} R ₅ include a phenoxy group, and the phenyl group includes a substituent that may be substituted with the cycloalkyl group such as an alkyl group or a halogen atom. May be substituted.

Examples of the aralkyloxy group represented by R _{1 to} R ₅ include a benzyloxy group and a phenethyloxy group, and these substituents may be further substituted. Preferred substituents include the above cycloalkyl The group which may be substituted with a group can be mentioned similarly.

Examples of the acyl group represented by R _{1 to} R ₅ include an unsubstituted acyl group having 2 to 8 carbon atoms such as an acetyl group and a propionyl group (the hydrocarbon group of the acyl group includes alkyl, alkenyl, alkynyl). These substituents may be further substituted, and preferred substituents include the same groups that may be substituted with the cycloalkyl group.

As the carbonyloxy group represented by R _{1 to} R ₅ , an unsubstituted acyloxy group having 2 to 8 carbon atoms such as acetyloxy group and propionyloxy group (the hydrocarbon group of the acyl group is alkyl, alkenyl, alkynyl). And arylcarbonyloxy groups such as a benzoyloxy group, and these groups may be further substituted with the same groups as those which may be substituted with the cycloalkyl group.

The oxycarbonyl group represented by R _{1 to} R ₅ represents an alkoxycarbonyl group such as a methoxycarbonyl group, an ethoxycarbonyl group or a propyloxycarbonyl group, or an aryloxycarbonyl group such as a phenoxycarbonyl group.

  These substituents may be further substituted, and preferred examples of the substituent include the same groups that may be substituted with the cycloalkyl group.

The oxycarbonyloxy group represented by R _{1 to} R ₅ represents an alkoxycarbonyloxy group having 1 to 8 carbon atoms such as a methoxycarbonyloxy group, and these substituents may be further substituted and are preferably substituted. Examples of the group include the same groups that may be substituted on the cycloalkyl group.

Any one of R _{1 to} R ₅ may be connected to each other to form a ring structure.

The linking group represented by L represents a substituted or unsubstituted alkylene group, an oxygen atom, or a direct bond, and the alkylene group is a group such as a methylene group, an ethylene group, or a propylene group. These groups may be further substituted with the groups mentioned as groups that may be substituted with the groups represented by R _{1 to} R ₅ .

  Among these, a direct bond and an aromatic carboxylic acid are particularly preferable as the linking group represented by L.

  Further, the organic acid represented by the general formula (3) constituting the ester compound serving as a plasticizer includes at least R1 or R2 as the alkoxy group, acyl group, oxycarbonyl group, carbonyloxy group, oxycarbonyloxy group. Those having a group are preferred. A compound having a plurality of substituents is also preferred.

  In addition, the organic acid which substitutes the hydroxyl group of trihydric or more alcohol may be single type, or may be multiple types.

  The trihydric or higher alcohol compound that reacts with the organic acid represented by the general formula (3) to form a polyhydric alcohol ester compound is preferably a 3-20 valent aliphatic polyhydric alcohol. As for the above alcohol, what is represented by following General formula (4) is preferable.

Formula (4) R '-(OH) m
In the formula, R ′ represents an m-valent organic group, m represents a positive integer of 3 or more, and the OH group represents an alcoholic hydroxyl group. Particularly preferred is a polyhydric alcohol having 3 or 4 as m.

  Examples of preferred polyhydric alcohols include, but are not limited to, the following.

  Adonitol, arabitol, 1,2,4-butanetriol, 1,2,3-hexanetriol, 1,2,6-hexanetriol, glycerin, diglycerin, erythritol, pentaerythritol, dipentaerythritol, tripentaerythritol, ga Examples include lactitol, inositol, mannitol, 3-methylpentane-1,3,5-triol, pinacol, sorbitol, trimethylolpropane, trimethylolethane, and xylitol.

  In particular, glycerin, trimethylolethane, trimethylolpropane, and pentaerythritol are preferable.

  The ester of the organic acid represented by the general formula (3) and the trihydric or higher polyhydric alcohol represented by the general formula (4) can be synthesized by a known method. In the examples, typical synthesis examples are shown. For example, the organic acid represented by the general formula (3) and the polyhydric alcohol represented by the general formula (4) are condensed and esterified in the presence of an acid, for example. There are a method, a method in which an organic acid is preliminarily converted into an acid chloride or an acid anhydride and a reaction with a polyhydric alcohol, a method in which a phenyl ester of an organic acid is reacted with a polyhydric alcohol, and the like. It is preferable to select a method with good yield.

  As a plasticizer comprising an organic acid represented by the general formula (3) and an ester of a trihydric or higher polyhydric alcohol represented by the general formula (4), a compound represented by the following general formula (5) is preferable. .

In the formula, R _{6 to} R ₂₀ represent a hydrogen atom or a cycloalkyl group, an aralkyl group, an alkoxy group, a cycloalkoxy group, an aryloxy group, an aralkyloxy group, an acyl group, a carbonyloxy group, an oxycarbonyl group, or an oxycarbonyloxy group. These may be further substituted. R21 represents a hydrogen atom or an alkyl group.

Cycloalkyl groups R ₆ to R _20, aralkyl group, alkoxy group, cycloalkoxy group, aryloxy group, aralkyloxy group, acyl group, carbonyloxy group, an oxycarbonyl group, for oxy carbonyloxy group, the general formula ( The same group as R < ₁ > -R < ₅ > of 3) is mentioned.

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

<Aromatic terminal polyester plasticizer>
An aromatic terminal polyester plasticizer represented by the following general formula (6) can be used.

General formula (6) B- (GA) n-GB
(In the formula, B is an arylcarboxylic acid residue, G is an alkylene glycol residue having 2 to 12 carbon atoms, an aryl glycol residue having 6 to 12 carbon atoms, or an oxyalkylene glycol residue having 4 to 12 carbon atoms, A Represents an alkylene dicarboxylic acid residue having 4 to 12 carbon atoms or an aryl dicarboxylic acid residue having 6 to 12 carbon atoms, and n represents an integer of 1 or more.)
In general formula (6), an arylcarboxylic acid residue represented by B and an alkylene glycol residue or oxyalkylene glycol residue or arylglycol residue represented by G, an alkylenedicarboxylic acid residue or aryldicarboxylic acid represented by A And is obtained by the same reaction as a normal polyester compound.

  Examples of the arylcarboxylic acid component of the aromatic-terminated polyester plasticizer include benzoic acid, para-tert-butylbenzoic acid, orthotoluic acid, metatoluic acid, p-toluic acid, dimethylbenzoic acid, ethylbenzoic acid, normal propylbenzoic acid, amino There exist benzoic acid, acetoxybenzoic acid, etc., These can be used as a 1 type, or 2 or more types of mixture, respectively.

  Examples of the alkylene glycol component having 2 to 12 carbon atoms of the aromatic terminal polyester plasticizer include ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,2-butanediol, and 1,3-butanediol. 1,2-propanediol, 2-methyl 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 2,2-dimethyl-1,3-propanediol (neopentyl glycol), 2,2-diethyl-1,3-propanediol (3,3-dimethylolpentane), 2-n-butyl-2-ethyl-1,3-propanediol (3,3-dimethylolheptane), 3-methyl -1,5-pentanediol 1,6-hexanediol, 2,2,4-trimethyl 1,3-pentanediol, 2- There are til 1,3-hexanediol, 2-methyl 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,12-octadecanediol, and the like. Used as a mixture of two or more.

  In particular, an alkylene glycol having 2 to 12 carbon atoms is particularly preferable because of excellent compatibility with a cellulose ester.

  Examples of the oxyalkylene glycol component having 4 to 12 carbon atoms of the aromatic terminal polyester plasticizer include diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, and tripropylene glycol. Can be used as one or a mixture of two or more.

  Examples of the alkylene dicarboxylic acid component having 4 to 12 carbon atoms of the aromatic terminal polyester plasticizer include succinic acid, maleic acid, fumaric acid, glutaric acid, adipic acid, azelaic acid, sebacic acid, and dodecanedicarboxylic acid. These are each used as one or a mixture of two or more.

  Examples of the arylene dicarboxylic acid component having 6 to 12 carbon atoms include phthalic acid, terephthalic acid, isophthalic acid, 1,5 naphthalene dicarboxylic acid, and 1,4 naphthalene dicarboxylic acid.

  In the aromatic terminal polyester plasticizer, n is preferably 1 or more and 100 or less, and the number average molecular weight is preferably 300 to 1500, more preferably 400 to 1000.

  The acid value is 0.5 mgKOH / g or less, the hydroxyl value is 25 mgKOH / g or less, more preferably the acid value is 0.3 mgKOH / g or less, and the hydroxyl value is 15 mgKOH / g or less.

  The aromatic terminal polyester plasticizer represented by the general formula (6) is preferably contained in an amount of 0.5 to 30% by mass with respect to the cellulose ester.

  Although the specific compound of an aromatic terminal polyester plasticizer is shown, it is not limited to this.

(Polymer plasticizer)
The cellulose ester film preferably uses a polymer plasticizer other than the acrylic polymer.

  Specifically, aliphatic hydrocarbon polymers, alicyclic hydrocarbon polymers, polyvinyl isobutyl ether, vinyl polymers such as poly N-vinyl pyrrolidone, copolymers of methyl methacrylate and N-vinyl pyrrolidone (for example, Copolymerization ratio (any ratio between 1:99 and 99: 1), polystyrene, styrene-based polymers such as poly-4-hydroxystyrene, polybutylene succinate, polyesters such as polyethylene terephthalate, polyethylene naphthalate, polyethylene oxide, polypropylene Examples include polyethers such as oxides, 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 1,000 or less, the volatility becomes large, and if it exceeds 500,000, the plasticizing ability tends to decrease, which may adversely affect the mechanical properties of the cellulose ester retardation film.

  These polymer plasticizers may be a homopolymer composed of one monomer repeating unit or a copolymer having a repeating structure of a plurality of monomers. Two or more of the above polymers may be used in combination.

  Further, the method for measuring the amount of plasticizer on the surface is not particularly limited. For example, a knife or the like is used to quantitatively analyze the surface of the film by cutting it about 20 nm or the amount of plasticizer in the thickness direction of the film is measured by IR or atomic absorption It is quantified using a method such as scanning with the above.

<Antioxidant>
As the antioxidant, those which are generally known can be used. In particular, lactone, sulfur, phenol, double bond, hindered amine, and phosphorus compounds can be preferably used.

  For example, the thing containing what is marketed by the brand name "IrgafosXP40" and "IrgafosXP60" from Ciba Japan KK is preferable.

  The phenolic compound preferably has a 2,6-dialkylphenol structure. For example, Ciba Japan Co., Ltd., “Irganox 1076”, “Irganox 1010”, ADEKA “ADEKA STAB AO-50” And those commercially available.

  Examples of the phosphorous compounds are Sumitomo Chemical Co., Ltd., “Sumilizer GP”, ADEKA Co., Ltd., “ADK STAB PEP-24G”, “ADK STAB PEP-36” and “ADK STAB 3010”, Ciba Japan Co., Ltd. "IRGAFOS P-EPQ", a product name and "GSY-P101" sold by Sakai Chemical Industry Co., Ltd. are preferable.

  The hindered amine compound is preferably commercially available from Ciba Japan Co., Ltd. as “Tinuvin 144 (AO2)” and “Tinvin 770”, and from ADEKA Co., Ltd. as “ADK STAB LA-52”.

  As the sulfur compound, for example, those commercially available from Sumitomo Chemical Co., Ltd. under the trade names of “Sumilizer TPL-R” and “Sumilizer TP-D” are preferable.

  The above-mentioned double bond type compounds are preferably those commercially available from Sumitomo Chemical Co., Ltd. under the trade names “Sumilizer GM” and “Sumilizer GS”.

  Furthermore, it is possible to include a compound having an epoxy group as described in US Pat. No. 4,137,201 as an acid and an agent.

  The amount of these antioxidants and the like to be appropriately added is determined in accordance with the process at the time of recycling, but generally 0.05 to 20% by mass, preferably with respect to the resin as the main raw material of the film Is added in the range of 0.1 to 1% by mass.

  These antioxidants can obtain a synergistic effect by using several different types of compounds in combination rather than using only one kind. For example, the combined use of lactone, phosphorus, phenol and double bond compounds is preferred.

<Retardation adjuster>
You may make the compound for adjusting retardation in the transparent film containing the cellulose-ester resin which has a repeating unit represented by General formula (1) or (2) contain.

  As the compound to be added for adjusting the retardation, an aromatic compound having two or more aromatic rings as described in EP 911,656A2 can also be used.

  Two or more aromatic compounds may be used in combination. The aromatic ring of the aromatic compound includes an aromatic heterocyclic ring in addition to the aromatic hydrocarbon ring. An aromatic heterocyclic ring is particularly preferred, and the aromatic heterocyclic ring is generally an unsaturated heterocyclic ring. Of these, compounds having a 1,3,5-triazine ring are particularly preferred.

<Colorant>
It is preferred to use a colorant. The colorant means a dye or a pigment, and refers to a colorant having an effect of making the color tone of a liquid crystal screen blue or adjusting a yellow index and reducing haze. Various dyes and pigments can be used as the colorant, but anthraquinone dyes, azo dyes, phthalocyanine pigments and the like are effective.

<Ultraviolet absorber>
The ultraviolet absorber is not particularly limited, and examples thereof include oxybenzophenone compounds, benzotriazole compounds, salicylic acid ester compounds, benzophenone compounds, cyanoacrylate compounds, triazine compounds, nickel complex compounds, inorganic powders, and the like. . It is good also as a polymer type ultraviolet absorber.

<Matting agent>
It is preferable to add a matting agent in order to impart the slipperiness of the film. As the matting agent, any inorganic compound or organic compound may be used as long as it has heat resistance at the time of melting without impairing the transparency of the resulting film. For example, talc, mica, zeolite, diatomaceous earth, calcined siliceous earth, Kaolin, sericite, bentonite, smectite, clay, silica, quartz powder, glass beads, glass powder, glass flake, milled fiber, wollastonite, boron nitride, boron carbide, titanium boride, magnesium carbonate, heavy calcium carbonate, Light calcium carbonate, calcium silicate, aluminum silicate, magnesium silicate, magnesium aluminosilicate, alumina, silica, zinc oxide, titanium dioxide, iron oxide, magnesium oxide, zirconium oxide, aluminum hydroxide, calcium hydroxide, magnesium hydroxide, calcium sulfate , Barium sulphate, silicon carbide, aluminum carbide, titanium carbide, aluminum nitride, silicon nitride, titanium nitride, and white carbon. These matting agents can be used alone or in combination of two or more. By using particles having different particle sizes and shapes (for example, acicular and spherical), both transparency and slipperiness can be made highly compatible.

  Among these, silicon dioxide is particularly preferably used since it has a refractive index close to that of cellulose ester and is excellent in transparency (haze). Specific examples of silicon dioxide include Aerosil 200V, Aerosil R972V, Aerosil R972, R974, R812, 200, 300, R202, OX50, TT600 (above Nippon Aerosil Co., Ltd.), Sea Hoster KEP-10, Sea Hoster KEP-30, Commercial products having trade names such as Seahoster KEP-50 (above, made by Nippon Shokubai Co., Ltd.), Silo Hovic 100 (made by Fuji Silysia), Nip Seal E220A (made by Nippon Silica Kogyo), Admafine SO (made by Admatechs), etc. Can be preferably used.

  The shape of the particles can be used without particular limitation, such as indefinite shape, needle shape, flat shape, spherical shape, etc. However, the use of spherical particles is particularly preferable because the transparency of the resulting film can be improved. When the particle size is close to the wavelength of visible light, light is scattered and the transparency is deteriorated. Therefore, the particle size is preferably smaller than the wavelength of visible light, and more preferably ½ or less of the wavelength of visible light. .

  If the size of the particles is too small, the slipperiness may not be improved, so the range of 80 nm to 180 nm is particularly preferable.

  The particle size means the size of the aggregate when the particle is an aggregate of primary particles. Moreover, when a particle is not spherical, it means the diameter of a circle corresponding to the projected area.

<Viscosity reducing agent>
For the purpose of reducing the melt viscosity, a hydrogen bonding solvent can be added. The hydrogen bonding solvent is J.I. N. As described in Israel Ativili, “Intermolecular Forces and Surface Forces” (Takeshi Kondo, Hiroyuki Oshima, Maglow Hill Publishing, 1991) and electrically negative atoms (oxygen, nitrogen, fluorine, chlorine) An organic solvent capable of producing a hydrogen atom-mediated “bond” between a hydrogen atom covalently bonded to an electronegative atom, ie, a bond having a large bond moment and containing hydrogen, such as O—H (Oxygen hydrogen bond), N—H (nitrogen hydrogen bond), and organic solvent that can arrange adjacent molecules by including F—H (fluorine hydrogen bond).

  These have the ability to form stronger hydrogen bonds with cellulose than intermolecular hydrogen bonds of cellulose resin. In the melt casting method performed in the present invention, the glass transition temperature of the cellulose resin used alone is higher than that. The melting temperature of the cellulose resin composition can be lowered by adding a hydrogen bonding solvent.

  Alternatively, the melt viscosity of the cellulose resin composition containing a hydrogen bonding solvent can be lowered than that of the cellulose resin at the same melting temperature.

  Examples of the hydrogen bonding solvent include alcohols: for example, methanol, ethanol, propanol, isopropanol, n-butanol, sec-butanol, t-butanol, 2-ethylhexanol, heptanol, octanol, nonanol, dodecanol, ethylene glycol, Propylene glycol, hexylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, methyl cellosolve, ethyl cellosolve, butyl cellosolve, hexyl cellosolve, glycerin, etc., ketones: acetone, methyl ethyl ketone, etc., carboxylic acids: eg formic acid, acetic acid, propionic acid, Butyric acid, etc., ethers: eg, diethyl ether, tetrahydrofuran, dioxane, etc., Pyrrolidones: eg, N-methyl Pyrrolidone, etc., amines: for example, can be exemplified trimethylamine, pyridine, etc., and the like.

  These hydrogen bonding solvents can be used alone or in admixture of two or more. Among these, alcohol, ketone, and ether are preferable, and methanol, ethanol, propanol, isopropanol, octanol, dodecanol, ethylene glycol, glycerin, acetone, and tetrahydrofuran are particularly preferable. Furthermore, water-soluble solvents such as methanol, ethanol, propanol, isopropanol, ethylene glycol, glycerin, acetone, and tetrahydrofuran are particularly preferable. Here, water-soluble means that the solubility in 100 g of water is 10 g or more. These solvents are volatilized at the time of melt film formation, and finally the content of the solvent is 0.01% by mass or less.

  Hereinafter, the film forming method of the cellulose ester film described above will be described.

<Melt casting method>
Melt casting is a process in which a composition containing an additive such as a cellulose ester and a plasticizer is heated and melted to a temperature showing fluidity, and then a melt containing the flowable cellulose ester is cast. Defined as melt film formation. More specifically, the heat melting molding method can be classified into a melt extrusion molding method, a press molding method, an inflation method, an injection molding method, a blow molding method, a stretch molding method, and the like. Among these, in order to obtain a cellulose ester film excellent in mechanical strength and surface accuracy, the melt extrusion method is excellent.

  Hereinafter, the melt casting film forming method will be described.

(Process for producing molten pellets of cellulose ester and additives)
It is preferable that a plurality of raw materials used for melt extrusion are usually kneaded and pelletized in advance. Pelletization may be performed by a known method. For example, dry cellulose ester, plasticizer, and other additives are fed to an extruder using a feeder, kneaded using a single or twin screw extruder, and extruded from a die into a strand. Can be done by water cooling or air cooling and cutting. It is important to dry the raw material before extruding to prevent decomposition of the raw material. In particular, since the cellulose ester easily absorbs moisture, it is preferable to dry it at 70 to 140 ° C. for 3 hours or more with a dehumidifying hot air dryer or a vacuum dryer to keep the moisture content at 200 ppm or less, and further 100 ppm or less.

  The additives may be mixed before being supplied to the extruder, or may be supplied by individual feeders. A small amount of additives such as antioxidants are preferably mixed in advance in order to mix more uniformly.

  Mixing of the antioxidants may be performed by mixing solids, and if necessary, the antioxidant may be dissolved in a solvent, impregnated with cellulose ester and mixed, or sprayed and mixed. Also good.

  A vacuum nauter mixer or the like is preferable because drying and mixing can be performed simultaneously. Moreover, when touching with air, such as an exit from a feeder part or die | dye, it is preferable to set it as atmosphere, such as dehumidified air and dehumidified N2 gas.

  In addition, it is preferable to keep the supply hopper and the like to the extruder warm because moisture absorption can be prevented.

  Matting agents, UV absorbers, and the like may be applied to the obtained pellets or added in an extruder during film formation.

  The extruder is preferably processed at as low a temperature as possible so as to be able to be pelletized so that the shearing force is suppressed and the resin does not deteriorate (decrease in molecular weight, coloring, gel formation, etc.). For example, in the case of a twin screw extruder, it is preferable to rotate in the same direction using a deep groove type screw. From the uniformity of kneading, the meshing type is preferable.

  Kneader discs can improve kneadability, but care must be taken against shearing heat generation. Mixability is sufficient without using a kneader disk. The suction from the vent hole may be performed as necessary. Since there is almost no volatile component at low temperatures, there may be no vent hole.

(Process of extruding a melt of cellulose ester and additive from the die)
The polymer dried after dehumidifying hot air, vacuum or reduced pressure was removed using a uniaxial or biaxial extruder, the melting temperature during extrusion was about 200 to 300 ° C, and filtered through a leaf disk type filter to remove foreign matter. Then, it is cast into a film from a T die and solidified on a cooling roll.

  When introducing from the supply hopper to the extruder, it is preferable to prevent oxidative decomposition or the like under vacuum, reduced pressure, or inert gas atmosphere.

  The extrusion flow rate is preferably performed stably by introducing a gear pump or the like. Further, a stainless fiber sintered filter is preferably used as a filter used for removing foreign substances.

  The stainless steel fiber sintered filter is a united stainless steel fiber body that is intricately intertwined and compressed, and the contact points are sintered and integrated. The density of the fiber is changed depending on the thickness of the fiber and the amount of compression, and the filtration accuracy is improved. Can be adjusted.

  It is preferable to use a multilayer body in which the filtration accuracy is repeated coarsely and densely multiple times. Further, it is preferable to adopt a configuration in which the filtration accuracy is sequentially increased or a method in which coarse and dense filtration accuracy is repeated, so that the filtration life of the filter can be extended and the accuracy of capturing foreign matters and gels can be improved.

  If flaws or foreign matter adhere to the die, streaky defects may occur. Such defects are also referred to as die lines, but in order to reduce surface defects such as die lines, it is preferable that the piping from the extruder to the die has a structure in which the resin retention portion is minimized. It is preferable to use a die that has as few scratches as possible inside the lip.

  The inner surface that contacts the molten resin such as an extruder or a die is preferably subjected to surface treatment that makes it difficult for the molten resin to adhere to the surface by reducing the surface roughness or using a material having a low surface energy. Specifically, a hard chrome plated or ceramic sprayed material is polished so that the surface roughness is 0.2 S or less.

  Additives such as plasticizers may be mixed with the resin in advance, or may be kneaded in the middle of the extruder. In order to add uniformly, it is preferable to use a mixing apparatus such as a static mixer.

(Process of casting while pressing the melt extruded from the die between the cooling roll and the elastic touch roll)
The film temperature on the touch roll side when the film is nipped between the cooling roll and the elastic touch roll is preferably Tg or more and Tg + 110 ° C. or less of the film. A well-known roll can be used for the roll which has the elastic body surface used for such a purpose. When peeling the film from the cooling roll, it is preferable to control the tension to prevent deformation of the film.

(Stretching process)
The film obtained as described above passes through the step of contacting the cooling roll, and then is further stretched in MD and TD at a stretching speed of 400% / min to 1500% / min, and the film is at least in the film forming direction or width. It is preferable to stretch 50% to 200% in either of the hand directions. This stretching step determines the elastic modulus of MD and TD of the present invention. As a method of stretching, a known roll stretching machine or tenter can be preferably used. It is preferable that the stretching temperature is usually performed in a temperature range of Tg to Tg + 60 ° C. of the resin constituting the film.

  The glass transition temperature Tg of the film constituting material can be controlled by varying the material type constituting the film and the ratio of the constituting material. When producing a retardation film, Tg is 110 ° C. or higher, preferably 125 ° C. or higher. If the Tg of the film is too high, the temperature is increased when the film constituent material is made into a film, so that the energy consumption for heating is increased, and the material itself may be decomposed when it is made into a film, resulting in coloring. Therefore, Tg is preferably 250 ° C. or lower.

  The stretching step may be carried out by known heat setting conditions, cooling, and relaxation treatment, and may be appropriately adjusted so as to have the characteristics required for the target retardation film.

  The stretching is preferably performed under a uniform temperature distribution controlled in the width direction. The temperature is preferably within ± 2 ° C, more preferably within ± 1 ° C, and particularly preferably within ± 0.5 ° C.

  Prior to winding, the ends may be slit and cut to the width of the product, and knurling (embossing) may be applied to both ends to prevent sticking or scratching during winding. The knurling method can process a metal ring having an uneven pattern on its side surface by heating or pressing.

  In addition, since the film has deform | transformed and cannot use as a product normally, the holding | grip part of the clip of both ends of a film is cut out and reused.

  The stretch ratio is 1% to 250%, more preferably 2% to 200%, and still more preferably 3% to 150% on at least one side. Although it may be stretched evenly in the vertical and horizontal directions, it is more preferable to stretch one of the stretch ratios more than the other and stretch the same.

  Either length (MD) or width (TD) may be increased, but the smaller draw ratio is preferably 0% to 30%, more preferably 0% to 25%, and still more preferably 0% to 20%. %. The larger draw ratio is 1% to 250%, more preferably 10% to 200%, and still more preferably 30% to 150%.

Stretch ratio (%) = 100 × {(Length after stretching) − (Length before stretching)} / (Length before stretching)
These longitudinal stretching and lateral stretching may be performed independently (uniaxial stretching) or may be performed in combination (biaxial stretching). In the case of biaxial stretching, it may be carried out in the longitudinal and transverse sequential manners (sequential stretching) or simultaneously (simultaneous stretching).

  Following such stretching, it is preferable to relax 0% to 10% in the longitudinal or transverse direction. Furthermore, it is also preferable to heat-fix at 150-250 degreeC for 1 second-3 minutes following extending | stretching.

  Here, Ro indicates in-plane retardation, the difference between the refractive index in the in-plane film forming direction MD and the refractive index in the width direction TD is multiplied by the thickness, and Rt indicates the thickness direction retardation. The difference between the in-plane refractive index (average of the film forming direction MD and the width direction TD) and the refractive index in the thickness direction is multiplied by the thickness.

  Stretching can be performed sequentially or simultaneously with respect to, for example, the film forming direction and the width direction of the film. At this time, if the stretching ratio in at least one direction is too small, a sufficient phase difference cannot be obtained, and if it is too large, stretching becomes difficult and film breakage may occur.

  Stretching in biaxial directions perpendicular to each other is an effective method for bringing the refractive indexes nx, ny, and nz of the film within a predetermined range.

  Here, nx is the refractive index in the film MD direction, ny is the refractive index in the TD direction, and nz is the refractive index in the thickness direction.

  For example, when stretching in the film forming direction, if the shrinkage in the width direction is too large, the value of nz becomes too large. In this case, the width shrinkage of the film can be suppressed or improved by stretching in the width direction. When stretching in the width direction, the refractive index may be distributed in the width direction.

  This distribution may appear when the tenter method is used, and by stretching the film in the width direction, a shrinkage force is generated in the center of the film, and the phenomenon is caused by the end being fixed, It is thought to be a so-called Boeing phenomenon.

  Even in this case, by stretching in the film forming direction, the bowing phenomenon can be suppressed and the distribution of retardation in the width direction can be reduced. By stretching in biaxial directions perpendicular to each other, film thickness fluctuations of the obtained film can be reduced. If the film thickness variation is too large, the phase difference becomes uneven, and unevenness such as coloring may be a problem when used in a liquid crystal display.

  The film thickness variation of the aforementioned cellulose ester film is preferably in the range of ± 3%, more preferably ± 1%.

  After stretching, after slitting the end of the film to a product width with a slitter, the film is subjected to knurling (embossing) on both ends of the film by a knurling device consisting of an embossing ring and a back roll, and a winder By taking up with, it prevents the cellulose ester film (original winding) from sticking and the generation of scratches.

(Solution casting film formation)
In film production by solution casting, a step of preparing a dope by dissolving a resin and an additive in a solvent, a step of casting the dope on a belt-shaped or drum-shaped metal support, and using the cast dope as a web It is performed by a step of drying, a step of peeling from the metal support, a step of stretching or maintaining the width, a step of further drying, and a step of winding up the finished film. The resin concentration in the dope is preferably higher because the drying load after casting on the metal support can be reduced, but if the resin concentration is too high, the load during filtration increases and the filtration accuracy deteriorates. . As a density | concentration which makes these compatible, 10-35 mass% is preferable, More preferably, it is 15-25 mass%.

  The metal support in the casting (casting) step preferably has a mirror-finished surface. As the metal support, a stainless steel belt or a drum whose surface is plated with a casting is preferably used. The cast width can be 1 to 4 m. The surface temperature of the metal support in the casting step is set to −50 ° C. to a temperature at which the solvent boils and does not foam. A higher temperature is preferable because the web can be dried faster, but if it is too high, the web may foam or the flatness may deteriorate. The 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%.

  The amount of residual solvent is defined by the following formula.

Residual solvent amount (% by mass) = {(MN) / N} × 100
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.

  In the film drying step, 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, and particularly preferably. 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 the film drying step, it is preferable to carry out the treatment while transporting in an atmosphere with an atmosphere substitution rate of 12 times / hour or more, preferably 12 to 45 times / hour.

The atmosphere substitution 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 wind blown into the heat treatment chamber is not a wind that is recycled and reused, and it means a fresh wind that does not contain volatilized solvent or plasticizer or has been removed. Yes.

Atmosphere replacement rate = FA / V (times / hour)
An atmosphere substitution rate of 12 times / hour or more is preferable because the plasticizer concentration in the atmosphere due to the plasticizer volatilized from the film can be sufficiently reduced, and reattachment to the film can be reduced.

(Form of hard coat film)
In recent years, thinning of image display devices has progressed, and thin films are also desired for members such as protective films and polarizing films used in image display devices. Conventionally, when the protective film is thinned, the film elasticity is lowered and is easily deformed. When the protective film is stored in a roll shape, the films adhere to each other and are likely to be blocked.

  The hard coat film of the present invention is easy to exert the effects of the present invention when the cellulose ester film, which is a transparent film, has a thin film thickness of 30 μm or less and is stored in a roll shape. In view of production efficiency, the hard coat film is preferably long, specifically 1000 m or more, preferably 3000 m or more, and more preferably 5000 m or more. In addition, the hard coat film (transparent film) is preferably a thin film when stored as a long film.

<Polarizing plate>
A polarizing plate using the hard coat film of the present invention will be described.

  The polarizing plate can be produced by a general method. The back surface side of the hard coat film of the present invention is subjected to alkali saponification treatment, and a completely hardened polyvinyl alcohol aqueous solution is used on at least one surface of a polarizing film prepared by immersing and stretching the treated hard coat film in an iodine solution. It is preferable to bond them together. The hard coat film may be used on the other surface, or another protective film may be used. The protective film used on the other surface of the hard coat film of the present invention is an optical compensation film (retardation) having an in-plane retardation Ro of 590 nm, a retardation of 20 to 100 nm, and an Rt of 100 to 400 nm. It is preferable to use a 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 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 or a nematic liquid crystal. For example, the optically anisotropic layer can be formed by the method described in JP-A-2003-98348. Alternatively, a non-oriented film having a retardation Ro of 590 nm of 0 to 5 nm and an Rt of -20 to +20 nm described in JP-A No. 2003-12859 is also preferably used. By using the hard coat film of the present invention in combination with a polarizing plate, a polarizing plate having excellent flatness can be obtained. As the protective film used on the back side, polyester film such as polyethylene terephthalate and polyethylene naphthalate, polyethylene film, polypropylene film, polycycloolefin film, cellophane, cellulose acetate film, cellulose acetate butyrate film, cellulose acetate phthalate film, cellulose Acetate propionate film, cellulose triacetate, cellulose ester such as cellulose nitrate or derivatives thereof, polyvinylidene chloride film, polyvinyl alcohol film, ethylene vinyl alcohol film, syndiotactic polystyrene film, polycarbonate film, cyclohexane Olefin polymer film ( For example, ARTON (manufactured by JSR), ZEONEX, ZEONOR (manufactured by ZEON CORPORATION), polymethylpentene film, polyetherketone film, polyethersulfone film, polysulfone film, polyetherketoneimide film, polyamide film, acrylic film Or a polyacrylate film etc. can be mentioned. Cellulose ester films such as cellulose acetate propionate film and cellulose triacetate film (TAC film) are commercially available films, such as Konica Minolta Op KONICA MINOLTATAC KC8UX, KC4UX, KC5UX, KC8UCR3, KC8UCR4, KC8UCR5, KC8UY KC4UY, KC12UR, KC16UR, KC4UE, KC8UE, KC4FR-1, KC4FR-2, etc. are preferably used. In addition, a cycloolefin polymer film, a polycarbonate film, a polyester film, or a polyacrylic film can also be preferably used in terms of transparency, mechanical properties, and lack of optical anisotropy.

  The polarizing film, which is the main component of the polarizing plate, is an element that transmits only light having a polarization plane in a certain direction. A typical polarizing film known at present is a polyvinyl alcohol polarizing film, which is a polyvinyl alcohol film. There are ones in which iodine is dyed on a system film and ones in which a dichroic dye is dyed, but it is not limited to this. As the polarizing film, a polyvinyl alcohol aqueous solution is formed and dyed by uniaxially stretching or dyed, or uniaxially stretched after dyeing, and then preferably subjected to a durability treatment with a boron compound. A polarizing film having a thickness of 5 to 30 μm, preferably 8 to 15 μm, is preferably used. On the surface of the polarizing film, one side of the hard coat film of the present invention is bonded to form a polarizing plate. It is preferably bonded with an aqueous adhesive mainly composed of completely saponified polyvinyl alcohol or the like. Further, the longer the polarizing plate, 1500 m, 2500 m, and 5000 m, are more preferable in terms of production efficiency.

<Display device>
By incorporating the polarizing plate produced using the hard coat film of the present invention into a display device, the display device of the present invention excellent in various visibility, flatness and surface hardness can be produced.

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

  Moreover, it is preferably used for various display devices such as a plasma display, a field emission display, an organic EL display, an inorganic EL display, and electronic paper.

  The liquid crystal display device of the present invention is used for a large liquid crystal television. As a screen size, it can be used for 17 or more types, preferably 26 to 100 types.

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

Example 1
Examples of the present invention will be described below, but the present invention is not limited thereto.

<Preparation of hard coat film 1>
<Production of Cellulose Ester Film A (Production of Transparent Film Consisting of Cellulose Ester Resin Having At least One Repeating Unit Represented by General Formula (1) or (2))>
(Synthesis of cellulose ester X)
To the reactor, 80 parts of cellulose acetate (Daicel Chemical Industries, Ltd., L-20, substitution degree 2.41) was added and dried under reduced pressure at 110 ° C. for 4 hours, 4 Torr (1 Torr is 133.322 Pa). . Thereafter, purging was performed with dry nitrogen, a reflux condenser was attached, 20 parts of ε-caprolactone and 67 parts of cyclohexanone that had been dried and distilled in advance were added, and the mixture was heated to 160 ° C. and stirred to dissolve cellulose acetate uniformly. To this reaction solution, 0.25 part of monobutyltin trioctylate was added and heated at 160 ° C. with stirring for 2 hours. Thereafter, the reaction solution was cooled to room temperature to terminate the reaction and obtain a reaction product. Furthermore, 10 parts of the reaction product was dissolved in 90 parts of chloroform, and then slowly dropped into 900 parts of a large excess of methanol, and the precipitated precipitate was filtered to remove the homopolymer of ε-caprolactone. . Furthermore, it heat-dried at 60 degreeC for 5 hours or more, and obtained the cellulose ester X which (epsilon) -caprolactone reacted with the cellulose acetate. And the primary structure of the cellulose ester obtained by < ¹ > H-NMR was analyzed. As a result, the average number of moles of ε-caprolactone reacted per mole of glucose unit was 0.43, the average degree of substitution was 0.08, and the average degree of polymerization was 5.1.

(Preparation of dope solution A)
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 solution A.

(Dope solution A)
Cellulose ester X 100 parts by mass Monopet SB (sugar ester compound) 9 parts by mass Silicon oxide fine particles 0.1 parts by mass (Aerosil R972V, manufactured by Nippon Aerosil Co., Ltd.)
Methylene chloride 400 parts by weight Ethanol 40 parts by weight Butanol 5 parts by weight The above materials are mixed to prepare a dope solution A. From the casting die in which the obtained dope solution A is kept at 35 ° C., stainless steel endless The web was formed by casting on a support composed of a belt and having a temperature of 35 ° C. Next, the web was dried on the support, and the web was peeled from the support with a peeling roll when the residual solvent amount of the web reached 100% by mass.

  Next, the web is transported while being dried with a drying air of 100 ° C. in a transport drying process using a plurality of rolls arranged on the upper and lower sides. Subsequently, both ends of the web are gripped by the tenter shown in FIG. (TD) was stretched to 1.2 times that before stretching. After stretching with a tenter, the web was dried with a drying air of 140 ° C. in a conveying and drying process using a plurality of rolls arranged vertically. After cooling to room temperature, both ends were subjected to a knurling process having a width of 1 cm and an average height of 15 μm and wound up to prepare a cellulose ester film A having a width of 1.5 m, a film thickness of 30 μm, a length of 6900 m, and a length. The draw ratio of the web conveyance direction (MD) 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.

Next, a hard coat layer coating solution is prepared by filtering the following hard coat layer coating composition 1 on the produced cellulose ester film A through a polypropylene filter having a pore size of 0.4 μm, and using the apparatus shown in FIG. After irradiating at 70 ° C. and purging with nitrogen so that the atmosphere has an oxygen concentration of 1.0% by volume or less, the illuminance of the irradiated part is 300 mW / cm ² and the irradiation amount is 0.3 J using an ultraviolet lamp. / Cm ² , and the coating layer is cured, and in the heat treatment zone 7 of FIG. 1, heat treatment is performed at 130 ° C. for 5 minutes at a conveyance tension of 300 N / m to form a hard coat layer having a dry film thickness of 18 μm. Film 1 was prepared and wound up.

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

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

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

  The weight average molecular weight was determined by GPC. Moreover, the mass% of the fluorine-siloxane graft polymer I was calculated | required by HPLC (liquid chromatography).

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

Pentaerythritol triacrylate 20.0 parts by mass Pentaerythritol tetraacrylate 50.0 parts by mass Dipentaerythritol hexaacrylate 30.0 parts by mass Dipentaerythritol pentaacrylate 30.0 parts by mass Irgacure 184 5.0 parts by mass (Ciba Japan Co., Ltd.) Made)
Fluoro-siloxane graft polymer I prepared above (35% by mass) 5.0 parts by mass Sea Hoster KEP-50 (powdered silica particles, average particle size 0.47 to 0.61 μm, manufactured by Nippon Shokubai Co., Ltd.) 24.3 Parts by mass propylene glycol monomethyl ether 20 parts by mass methyl acetate 40 parts by mass methyl ethyl ketone 60 parts by mass (measurement of Martens hardness)
The Martens hardness (HMs) of the hard coat layer surface of the hard coat film 1 was measured using a micro hardness meter. That is, using a microhardness meter (trade name, DUH-212, manufactured by Shimadzu Corporation) using a Vickers indenter and a triangular pyramid indenter having an angle of 115 degrees, first, a hard coat layer on the surface of the hard coat film The indenter was pushed to a thickness of about 1/10 of the film thickness, and a load test force-indentation depth curve when the indenter was pushed in was created. Next, from the created load test force-indentation depth curve, the indentation depth from the 50% value to the 90% value of the maximum load test force (Fmax) is as follows from the slope (m) proportional to the square root of the load test force. The Martens hardness (Hms) value of the hard coat layer surface defined by the formula was calculated.

1HMs = 1 / (26.4m ² )
As a result, the Martens hardness (HMs) of the hard coat layer surface of the hard coat film 1 was 408 N / mm ² .

<Preparation of hard coat films 2-4>
Similarly to the hard coat film 1, under the conditions shown in Table 1, the heat treatment conditions and tension in the heat treatment zone 7 of FIG. 1 were changed to produce hard coat film films 2 to 4. Further, the Martens hardness (HMs) on the surface of the hard coat layer was also measured and listed in Table 1.

<Preparation of hard coat films 5-10>
In preparation of the hard coat film 1, the film thickness was changed as shown in Table 1 to prepare hard coat film films 5 to 10. Further, the Martens hardness (HMs) on the surface of the hard coat layer was also measured and listed in Table 1.

<Preparation of hard coat film 11>
In the production of the hard coat film 1, a hard coat film 11 was produced in the same manner except that the transparent film was changed to the following cellulose ester film B.

<Preparation of cellulose ester film B>
(Synthesis of cellulose ester Y)
To the reactor, 80 parts of cellulose acetate (Daicel Chemical Industries, Ltd., L-20, substitution degree 2.41) was added and dried under reduced pressure at 110 ° C. for 4 hours, 4 Torr (1 Torr is 133.322 Pa). . Then, purging with dry nitrogen, attaching a reflux condenser, adding 80 parts of L-lactide (manufactured by Musashino Chemical Laboratories) and 67 parts of cyclohexanone that were dried and distilled in advance, and heating and stirring to 160 ° C. The cellulose acetate was uniformly dissolved. To this reaction solution, 0.25 part of monobutyltin trioctylate was added and heated at 160 ° C. with stirring for 2 hours. Thereafter, the reaction solution was cooled to room temperature to terminate the reaction and obtain a reaction product. Furthermore, 10 parts of the reaction product was dissolved in 90 parts of chloroform, and then slowly dropped into 900 parts of a large excess of methanol, and the precipitated precipitate was filtered off to remove the L-lactide homopolymer. . Furthermore, it heat-dried at 60 degreeC for 5 hours or more, and obtained the cellulose ester Y which (epsilon) -caprolactone reacted with the cellulose acetate. And the primary structure of the cellulose ester obtained by < ¹ > H-NMR was analyzed. As a result, the primary structure of the graft obtained by ¹ H-NMR was analyzed. As a result, the average number of moles of L-lactide reacted per mole of glucose unit was 1.80, the average degree of substitution was 0.33, and the average degree of polymerization was 7.1.

(Preparation of dope solution B)
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 solution B.

(Dope solution B)
Cellulose ester Y 100 parts by mass Monopet SB (sugar ester compound) 9 parts by mass Silicon oxide fine particles 0.1 parts by mass (Aerosil R972V, manufactured by Nippon Aerosil Co., Ltd.)
Methylene chloride 400 parts by weight Ethanol 40 parts by weight Butanol 5 parts by weight The above materials are mixed to prepare a dope solution B, and the obtained dope solution B is made of stainless steel endless from a casting die kept at a temperature of 35 ° C. The web was formed by casting on a support composed of a belt and having a temperature of 35 ° C. Next, the web was dried on the support, and the web was peeled from the support with a peeling roll when the residual solvent amount of the web reached 100% by mass.

  Next, the web is transported while being dried with a drying air of 100 ° C. in a transport drying process using a plurality of rolls arranged on the upper and lower sides. Subsequently, both ends of the web are gripped by a tenter and then stretched in the width direction (TD) at 130 ° C. It extended | stretched so that it might become 1.2 times before. After stretching with a tenter, the web was dried with a drying air of 140 ° C. in a conveying and drying process using a plurality of rolls arranged vertically. After cooling to room temperature, both ends were subjected to a knurling process having a width of 1 cm and an average height of 15 μm, and wound to prepare a cellulose ester film B having a width of 1.5 m, a film thickness of 30 μm, a length of 6900 m, and a length. The draw ratio of the web conveyance direction (MD) 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.

<Preparation of hard coat film 12>
In the production of the hard coat film 1, a hard coat film 12 was produced in the same manner except that the transparent film was changed to the cellulose triacetate film 1 described below.

(Preparation of cellulose triacetate film 1)
(Preparation of dope solution C)
The following materials were sequentially put into a sealed container, the temperature in the container was raised from 20 ° C. to 80 ° C., and then stirred for 3 hours while maintaining the temperature at 80 ° C. to completely dissolve the cellulose triacetate. . The silicon oxide fine particles were dispersed and added in a solution of a solvent to be added in advance and a small amount of cellulose triacetate. This dope was filtered using a filter paper (Azumi filter paper No. 244 manufactured by Azumi Filter Paper Co., Ltd.) to obtain a dope solution C.

(Dope solution C)
Cellulose triacetate (acetyl group substitution degree 2.9) 100 parts by weight Triphenyl phosphate (plasticizer) 7 parts by weight Biphenyl diphenyl phosphate (plasticizer) 4 parts by weight Fine particles of silicon oxide 0.1 part by weight (Aerosil R972V, Nippon Aerosil Co., Ltd.) Made)
Methylene chloride 400 parts by weight Ethanol 40 parts by weight Butanol 5 parts by weight The above materials are mixed to prepare a dope liquid C, and the obtained dope liquid C is passed through a casting die kept at a temperature of 35 ° C. A web was formed by casting on a support made of an endless belt made at a temperature of 35 ° C. Next, the web was dried on the support, and the web was peeled from the support with a peeling roll when the residual solvent amount of the web reached 100% by mass.

  Next, the web is transported while being dried with a drying air of 100 ° C. in a drying process of transport by a plurality of rolls arranged on the top and bottom, and subsequently grips both ends of the web with a tenter, and then in the width direction (TD) at 130 ° C. It extended | stretched so that it might be 1.2 times before extending | stretching. After stretching with a tenter, the web was dried with a drying air of 140 ° C. in a conveying and drying process using a plurality of rolls arranged vertically. Next, the mixture was cooled to room temperature, and both ends were subjected to a knurling process having a width of 1 cm and an average height of 15 μm and wound up to prepare a cellulose triacetate film 1 having a width of 1.5 m, a film thickness of 30 μm, and a length of 6900 m.

<Preparation of hard coat film 13>
In the production of the hard coat film 1, the cellulose ester film A is a cycloolefin polymer 1 (COP1: thickness 30 μm) produced with reference to Example 3 of JP-A-2006-291192, and surface treatment is performed by atmospheric pressure plasma treatment. Thereafter, a hard coat film 13 was produced in the same manner except that a hard coat layer was formed.

<Preparation of cycloolefin polymer film 1 (COP1)>
(Synthesis of cycloolefin polymer 1)
In a reaction vessel purged with nitrogen, 225 parts of 8-methyl-8-carboxymethyltetracyclo [4.4.0.12, 5.17,10] -3-dodecene and bicyclo [2.2.1] hept- 25 parts of 2-ene, 18 parts of 1-hexene as a molecular weight regulator and 750 parts of toluene as a solvent were charged, and this solution was heated to 60 ° C. Next, 0.62 parts of a toluene solution containing 1.5 mol / l of triethylaluminum as a polymerization catalyst and tungsten hexachloride modified with t-butanol and methanol (t-butanol: methanol: tungsten) were added to the solution in the reaction vessel. = 0.35 mol: 0.3 mol: 1 mol) containing 3.7 parts of a 0.05 mol / l toluene solution, and the system was opened by heating and stirring at 80 ° C. for 3 hours. A ring-opening copolymer solution was obtained by a ring copolymerization reaction. The polymerization conversion rate in this polymerization reaction was 97%, and the intrinsic viscosity (η _inh ) in 30 ° C. chloroform of the ring-opening copolymer constituting the obtained ring-opening copolymer solution was measured. The autoclave was charged with 4000 parts of the resulting ring-opening copolymer solution that was 65 dl / g, and carbonylchlorohydridotris (triphenylphosphine) ruthenium: RuHCl (CO) [P (C ₆ H _{5) 3] 3} was added 0.48 parts of a hydrogen gas pressure of 100 kg / cm ^2, was subjected to hydrogenation reaction by heating for 3 hours stirring under the conditions of reaction temperature of 165 ° C.. After cooling the obtained reaction solution (hydrogenated polymer solution), the hydrogen gas was released. This reaction solution was poured into a large amount of methanol to separate and recover a coagulated product, which was dried to obtain a hydrogenated polymer (hereinafter “cycloolefin polymer 1”). With respect to the obtained cycloolefin polymer 1, the hydrogenation rate was measured by means of 400 MHz ¹ H-NMR spectrum and found to be 99.9%. Further, when the number average molecular weight (Mn) and the mass average molecular weight (Mw) in terms of polystyrene were measured by the GPC method (solvent: tetrahydrofuran), the number average molecular weight (Mn) was 39,000, and the mass average molecular weight (Mw) was 126. The molecular weight distribution (Mw / Mn) was 3.23.

(Preparation of dope solution D)
Cycloolefin polymer 1 was dissolved in toluene to a concentration of 30%. The solution viscosity at room temperature of the obtained solution was 30,000 mPa · s. To this solution, pentaerythrityltetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] as an antioxidant was added in an amount of 0.1 mass per 100 mass parts of the cycloolefin polymer. And 0.1 part by mass of silicon oxide fine particles and 100 parts by mass of cycloolefin polymer 1 were added to prepare a dope solution D.

  The obtained dope solution D was filtered using a metal fiber sintered filter made by Nippon Pole with a pore diameter of 5 μm while controlling the flow rate of the solution so that the differential pressure was within 0.4 MPa, and then kept at a temperature of 35 ° C. The cast die was passed through and cast on a support made of stainless steel endless belt at a temperature of 35 ° C. to form a web. Next, the web was dried on the support, and the web was peeled from the support with a peeling roll when the residual solvent amount of the web reached 80% by mass.

Next, the web is transported while being dried with a drying air of 110 ° C. in a drying process of transport by a plurality of rolls arranged on the top and bottom, and subsequently grips both ends of the web with a tenter, and then in the width direction (TD) at 150 ° C. It extended | stretched so that it might be 1.2 times before extending | stretching. After stretching with a tenter, the web was dried with a drying air of 165 ° C. in a transport drying process using a plurality of rolls arranged vertically. Next, it was cooled to room temperature, and both ends were subjected to a knurling process having a width of 1 cm and an average height of 15 μm and wound up to prepare a cycloolefin polymer film 1 having a width of 1.5 m, a film thickness of 30 μm, and a length of 6900 m.
<< Evaluation of hard coat film >>
The following evaluation was implemented using the produced hard coat films 1-13.

(Surface hardness: pencil hardness)
The surface hardness of the hard coat films 1 to 13 was evaluated by a pencil hardness test. Using the test pencil specified by JIS-S6006, according to the pencil hardness evaluation method specified by JIS-K5400, the surface of the hard coat layer was scratched 5 times with a pencil of each hardness using a weight of 500 g, and scratches were 1 The hardness up to the book was measured. The higher the number, the higher the hardness. In the present invention, 3H or more has high hardness.

(Blocking resistance evaluation)
The roll film of the hard coat films 1-13 produced above (a state where the hard coat layer and the layer not forming the hard coat overlap) was stored for 11 days in a constant temperature bath at 55 ° C. and a relative humidity of 80%. . Next, the blocking property after storage was evaluated based on the following criteria by visual observation from the surface. The results are shown in Table 1.

  A: Sticking area 0%, no blocking observed.

  ○: The sticking area is less than 2%, and slightly blocking occurs.

Δ: Although the sticking area is 2% or more and less than 10%, blocking is occurring,
There is no problem in practical use.

  X: The sticking area is 10% to less than 40%, and blocking occurs.

  XX: The sticking area is 40% or more, which is extremely problematic for practical use.

(Flatness)
Ten sets of daylight direct fluorescent lamps (FLR40S • D / MX manufactured by Panasonic Corporation) 40W × 2 were set on a ceiling portion 3 m high from the floor, with 1.5 m intervals. Next, each 1 m of the hard coat films 1 to 13 was cut out, placed on a black desk 80 cm from the floor with the hard coat layer on the surface side so that the fluorescent lamp was perpendicular to the hard coat film, and evaluated according to the following criteria. .

○: Fluorescent lamp looks straight △: Fluorescent lamp appears to be slightly bent, but it is at a level that does not cause any practical problems.

  X: The fluorescent lamp looks bent.

(Comprehensive evaluation)
From the evaluation of hardness, blocking resistance and flatness, Table 1 shows the overall evaluation as a general evaluation.

A: Hardness of 4H or more, blocking and flatness of ◯ or more ○: Hardness of 3H or more, blocking and flatness of ◯ or more Δ: Hardness of 3H or more, blocking and flatness of △,
Alternatively, either blocking or flatness is Δ, and the other is ◯ or more. X: Hardness is 3H or more, and either blocking or flatness is X or less. XX: Hardness is less than 3H. level.

  The obtained results are shown in Table 1.

  As can be seen from the results in Table 1, a cellulose ester film having a hard coat layer thickness of 8 μm or more and 40 μm or less and having at least one repeating unit represented by the general formula (1) or (2) in the transparent film is used. Therefore, it is excellent in all of high hardness, flatness and blocking resistance. In particular, when the film thickness of the hard coat layer is 14 μm or more and 26 μm or less, the excellent effect of the present invention is exhibited.

  When the thickness of the hard coat layer is thinner than 8 μm, the blocking property is excellent, but high hardness cannot be obtained.

  When the film thickness of the hard coat layer is thicker than 40 μm, high hardness is obtained, but good performance in blocking property and flatness cannot be obtained.

Example 2
<Preparation of hard coat films 14 and 15>
In the production of the hard coat film 2, the heat treatment zone 7 of FIG. 1 was passed through, but the heat treatment was not performed (room temperature: 25 ° C.), except that the condition of the conveyance tension was changed to the actual condition (200 N / m), A hard coat film 14 was produced. Further, in the production of the hard coat film 2, the hard coat film 15 was produced in the same manner except that the condition of the transport tension was changed to 550 N / m.

  The Martens hardness (HMs) of the hard coat layer surfaces of the hard coat films 14 and 15 was also measured and listed in Table 2.

  Next, the hard coat films 14 and 15 produced above and the hard coat film 2 produced in Example 1 were evaluated in the same manner as in Example 1 except that the storage period of the blocking resistance evaluation was changed to 16 days. The obtained results are shown in Table 2.

  As can be seen from the results in Table 2, it can be seen that a hard coat film with more excellent blocking resistance can be obtained by setting the heat treatment and the transport tension to 300 N / m or more after the light irradiation. Moreover, the outstanding planarity is also acquired by making conveyance tension into 500 N / m or less.

Example 3
<Preparation of hard coat film 16>
In the production of the hard coat film 1, a hard coat film 16 was produced in the same manner except that the hard coat layer coating composition 1 was changed to the following hard coat layer coating composition 2. Next, the hard coat film 16 produced above and the hard coat film 1 produced in Example 1 were the same as in Example 1 except that the durability test condition for blocking resistance evaluation was changed to 70 ° C. and 90% relative humidity. evaluated. The obtained results are shown in Table 3. The Martens hardness of the hard coat film 16 is also shown in Table 3.
(Hard coat layer composition 2)
<Preparation of reactive silica particles (Xa)>
(Preparation of organic compound (X) having a polymerizable unsaturated group)
To a solution consisting of 23 parts of mercaptopropyltrimethoxysilane and 0.5 parts of dibutyltin dilaurate, 60 parts of isophorone diisocyanate was added dropwise at 50 ° C. over 1 hour while stirring and then stirred at 70 ° C. for 3 hours. NK ester A-TMM-3LM-N manufactured by Shin-Nakamura Chemical Co., Ltd. (202 parts of a solution composed of 60% by mass of pentaerythritol triacrylate and 40% by mass of pentaerythritol tetraacrylate) was added dropwise at 30 ° C. over 1 hour, and then 60 ° C. The specific organic compound (S1) was obtained by heating and stirring at 3 ° C. The infrared absorption spectrum of the product had an absorption peak of 2550 cm ⁻¹ characteristic of the mercapto group in the raw material and 2260 cm ⁻ characteristic of the isocyanate group. ¹ disappears, and a new 1660 cm ⁻¹ characteristic of the carbonyl in the [—O—C (═O) —NH—] and [—S—C (═O) —NH—] groups. Peak and 1720 cm ⁻¹ peak characteristic of acryloyl group were observed, and acryloyl group as a polymerizable unsaturated group and [—S—C (═O) —NH It was shown that a specific organic compound having both a [-] group and a [-O-C (= O) -NH-] group was formed, 9.36 parts of the composition prepared above (with polymerizable unsaturated groups). Containing 7.28 parts of organic compound (X)), silica particle dispersion (silica concentration 31%, MEK sol manufactured by Nissan Chemical Industries) 98.07 parts, ion-exchanged water 0.13 parts, and p-hydroxyphenyl monomethyl ether After 0.01 part of the mixed liquid is stirred at 60 ° C. for 4 hours, 1.45 parts of orthoformate methyl ester is added, and the mixture is further heated and stirred at the same temperature for 1 hour to obtain a dispersion of reactive silica particles (Xa). 2 g of this dispersion was weighed in an aluminum dish, dried on a hot plate at 175 ° C. for 1 hour, and weighed to determine the solid content, which was 35.7%. The average particle size was 40 nm. In this, the average particle diameter was measured by a transmission electron microscope.

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

Pentaerythritol triacrylate 20.0 parts by mass Pentaerythritol tetraacrylate 50.0 parts by mass Dipentaerythritol hexaacrylate 30.0 parts by mass Dipentaerythritol pentaacrylate 30.0 parts by mass Irgacure 184 5.0 parts by mass (Ciba Japan Co., Ltd.) Made)
Fluoro-siloxane graft polymer I prepared above (35% by mass) 5.0 parts by mass Reactive silica particle dispersion (reactive silica particles (Xa) 35.7%) 68 parts by mass Propylene glycol monomethyl ether 20 parts by mass Methyl acetate 40 parts by weight

  As can be seen from the results in Table 3, by including reactive silica particles (Xa) surface-treated with an organic compound having a polymerizable unsaturated group in the hard coat layer, it is excellent in blocking resistance after a more severe durability test. In addition, high hardness performance can be obtained.

Example 4
<Preparation of hard coat films 17-22>
In the production of the hard coat film 1, the cellulose ester film A is a cellulose ester resin having at least one repeating unit represented by the general formula (1) or (2) (described as cellulose ester X in Table 4) and thermoplasticity. A dope solution was prepared by mixing acrylic resin at a ratio shown in Table 4. Next, a cellulose ester resin / thermoplastic acrylic resin film was produced using these dope solutions, and hard coat films 17 to 22 were produced in the same manner except that these films were used as substrates. Next, for the hard coat films 17 to 22 produced above and the hard coat film 1 produced in Example 1, the durability test conditions for blocking resistance evaluation were 70 ° C. relative humidity 90%, and the storage period was changed to 20 days. Were evaluated in the same manner as in Example 1. The results obtained are shown in Table 4. Table 4 also shows the Martens hardness of the hard coat films 17 to 22. As the thermoplastic acrylic resin, Dianal BR85 (weight average molecular weight (Mw): 280000, manufactured by Mitsubishi Rayon Co., Ltd.) was used.

  As can be seen from the results in Table 4, the transparent film is heated with respect to 100 parts by mass of the cellulose ester resin having at least one repeating unit represented by the general formula (1) or (2) and the cellulose ester resin. It turns out that it is excellent in blocking resistance after a more severe durability test by containing a plastic acrylic resin in the ratio in 10 mass parts or more. Furthermore, high hardness performance is obtained in addition to excellent blocking resistance by containing a thermoplastic acrylic resin in a proportion of 50 parts by mass or more with respect to 100 parts by mass of the cellulose ester resin.

Reference example 1
<Preparation of antireflection films 1 and 2>
The hard coat films 1 and 13 prepared in Example 1 and subjected to the durability test (stored in a constant temperature bath at 55 ° C. and 80% for 11 days) were again drawn out, and atmospheric pressure plasma treatment was performed on the hard coat layer. Then, after applying and drying the following low refractive index layer coating solution 1, it was thermally cured at 120 ° C. for 5 minutes, further cured by irradiation with ultraviolet rays, and a low refractive index layer having a thickness of 85 nm was provided and wound into a roll. I took it. Subsequently, the film was subjected to heat aging treatment at 45 ° C. for 5 days to produce antireflection films 1 and 2.

  The refractive index of the low refractive index layer was 1.38. The center line average roughness (Ra) of the surface of the low refractive index layer was 100 nm or less and was smooth.

(Low refractive index layer coating solution 1)
<Preparation of tetraethoxysilane hydrolyzate A>
Tetraethoxysilane hydrolyzate A was prepared by mixing 58 g of tetraethoxysilane and 114 g of ethanol and adding 60 g of an acetic acid aqueous solution (1%) thereto, followed by stirring at 25 ° C. for 1 hour.

Tetraethoxysilane hydrolyzate A 59.5 parts by mass The following silica-based fine particles P-1 35 parts by mass γ-methacryloxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., KBM503)
5 parts by mass FZ-2222 (Nihon Unicar, 10% propylene glycol monomethyl ether solution) 0.5 parts by mass Isopropyl alcohol 500 parts by mass Propylene glycol monomethyl ether (PGME) 300 parts by mass Methyl ethyl ketone (MEK) 100 parts by mass <Silica-based fine particles Preparation of P-1>
A mixture of 100 g of silica sol having an average particle diameter of 5 nm and a SiO ₂ concentration of 20% by mass and 1900 g of pure water was heated to 80 ° C. The pH of this reaction mother liquor was 10.5, and 9000 g of 0.98 mass% sodium silicate aqueous solution as SiO ₂ and 9000 g of 1.02 mass% sodium aluminate aqueous solution as Al ₂ O ₃ were simultaneously added to the mother liquor. did. Meanwhile, the temperature of the reaction solution was kept at 80 ° C. The pH of the reaction solution rose to 12.5 immediately after the addition and hardly changed thereafter. After completion of the addition, the reaction solution was cooled to room temperature and washed with an ultrafiltration membrane to prepare a SiO ₂ .Al ₂ O ₃ core particle dispersion having a solid content concentration of 20% by mass. (Process (a))
1700 g of pure water is added to 500 g of this core particle dispersion and heated to 98 ° C., and while maintaining this temperature, a silicate solution (SiO ₂₎ obtained by dealkalizing a sodium silicate aqueous solution with a cation exchange resin. A dispersion of core particles in which 3000 g (concentration of 3.5% by mass) was added to form a first silica coating layer was obtained. (Process (b))
Next, 1125 g of pure water is added to 500 g of the core particle dispersion liquid that has been washed with an ultrafiltration membrane to form a first silica coating layer having a solid content concentration of 13% by mass, and concentrated hydrochloric acid (35.5%) is further added dropwise. The pH was adjusted to 1.0 and dealumination was performed. Next, the aluminum salt dissolved in the ultrafiltration membrane is separated while adding 10 L of hydrochloric acid aqueous solution of pH 3 and 5 L of pure water, and SiO ₂ · Al in which some of the constituent components of the core particles forming the first silica coating layer are removed. A dispersion of ₂ O ₃ porous particles was prepared (step (c)). A mixture of 1500 g of the above porous particle dispersion, 500 g of pure water, 1,750 g of ethanol, and 626 g of 28% ammonia water is heated to 35 ° C., and then 104 g of ethyl silicate (SiO ₂ 28 mass%) is added, A first silica coating layer was formed.

  The surface of the porous particles was coated with a hydrolyzed polycondensate of ethyl silicate to form a second silica coating layer. Next, a dispersion of silica-based fine particles (P-1) having a solid content concentration of 20% by mass in which the solvent was replaced with ethanol using an ultrafiltration membrane was prepared.

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

(Reflective color unevenness)
The reflection color unevenness was evaluated by the following criteria by visual observation of the produced antireflection film. The results are shown in Table 5.

◎: 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

  As can be seen from the results in Table 5, it was found that the antireflection film produced using the hard coat film of the present invention showed excellent performance in uneven reflection color.

Example 5
According to the following method, the hard coat films 1 to 13 prepared in Example 1 and subjected to the durability test (stored in a constant temperature bath at 55 ° C. and 80% for 11 days) and Konica Minolta Tack KC4FR-1 (retardation film) Polarizers 101 to 113 were produced using one each as a polarizing plate protective film, manufactured by Konica Minolta Opto Corporation.
(A) Production of Polarizing Film A long polyvinyl alcohol film having a thickness of 120 μm was uniaxially stretched (temperature: 110 ° C., stretch ratio: 5 times). This was immersed in an aqueous solution composed of 0.075 g of iodine, 5 g of potassium iodide, and 100 g of water for 60 seconds, and then immersed in an aqueous solution at 68 ° C. composed of 6 g of potassium iodide, 7.5 g of boric acid, and 100 g of water. . This was washed with water and dried to obtain a long polarizing film.

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

  Step 1: The hard coat film and KC4FR-1 were 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 KC4FR-1 and the hard coat film that had been subjected to alkali treatment in Step 1, and laminated.

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

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

  Carefully peel off the polarizing plate on the outermost surface of a commercially available liquid crystal display panel (NEC color liquid crystal display MultiSync LCD1525J: model name LA-1529HM). The liquid crystal display devices 501 to 513 were attached so as to be on the surface side. As a result of comparing the smoothness and visibility of the produced liquid crystal display device, the liquid crystal display device using the hard coat film of the present invention has both smoothness and visibility as compared with those using the hard coat film of the comparative example. It was good.

Example 6
In the production of the hard coat film 1 of Example 1, hard coat films 23 and 24 were produced in the same manner except that the film thickness of the cellulose ester film A as the base film was changed to 10 μm and 8 μm. Next, the hard coat films 1, 23 and 24 were evaluated in the same manner as in Example 1. The results obtained are shown in Table 6.

  As can be seen from the results in Table 6, it can be seen that the effect of the present invention is satisfactorily exhibited when the thickness of the base film is 10 μm or more.

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

Explanation of symbols

Y Long film 1 Feeding roll 2 Conveying roller 3 Extrusion coater 4 Opposing roll 5 Drying zone 6 Actinic ray irradiation lamp unit 6a Air-cooling actinic ray lamp 6b Air cooling air vent 6c N2 supply chamber 7 Heating zone 8 Winding chamber 9 Winding Take-up roll 10 Hot air outlet 12 Moveable cart 15 Winding core A Heat treatment chamber

Claims (10)

In a hard coat film having a hard coat layer on a transparent film substrate, the thickness of the hard coat layer is 8 μm or more and 40 μm or less, and the transparent film substrate is represented by the following general formula (1) or (2 A hard coat film comprising a cellulose ester resin having at least one repeating unit represented by

[In formula, A and B represent a C1-C12 bivalent hydrocarbon group or a C1-C12 bivalent hydrocarbon group substituted by the hydroxyl group. However, A and B may be the same or different. ] The hard coat film according to claim 1, wherein the transparent film substrate contains a thermoplastic acrylic resin, and the thermoplastic acrylic resin is contained in an amount of 10 parts by mass or more based on 100 parts by mass of the cellulose ester resin. . The hard coat film according to claim 1, wherein the transparent film substrate contains a thermoplastic acrylic resin, and the thermoplastic acrylic resin is contained in an amount of 50 parts by mass or more based on 100 parts by mass of the cellulose ester resin. . The hard coat according to any one of claims 1 to 3, wherein the hard coat layer contains reactive silica particles (Xa) surface-treated with an organic compound having a polymerizable unsaturated group. the film. The Martens hardness of the hard coat layer (HMS) is, 400 N / mm ² or more, the hard coating film according to claim 1, characterized in that there at 800 N / mm ² or less. The film thickness of the said transparent film base material is 10 micrometers or more and 30 micrometers or less, The hard coat film of any one of Claims 1-5 characterized by the above-mentioned. In the formation of the hard coat layer of the hard coat film of any one of Claims 1-6, it comprises the process of heat-processing after light irradiation, The manufacturing method of the hard coat film characterized by the above-mentioned. The method for producing a hard coat film according to claim 7, wherein in the heat treatment step, the hard coat film is tensioned at 300 N to 500 N / m in the conveyance direction or the width direction. A polarizing plate characterized by using the hard coat film according to any one of claims 1 to 6 on one surface. A display device comprising the polarizing plate according to claim 9.

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