JP5022597B2 - Optical film, antireflection film, polarizing plate, and image display device - Google Patents

Description

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

  Optical functional films are generally applied to image display devices such as cathode ray tube display devices (CRT), plasma displays (PDP), electroluminescence displays (ELD), and liquid crystal display devices (LCD). . Examples of such an optical film include an antireflection film, an antiglare film, a light scattering film, an optical compensation film, and a polarizing plate.

  These optical films are generally formed by a thin layer by a physical adsorption method such as a vacuum deposition method such as sputtering or an atmospheric pressure plasma deposition method. It is easy to deal with and has high productivity, and the demand has been increasing in recent years.

  Thin layer formation by a coating method often provides a functional layer by applying a solution onto a transparent support, particularly by applying a solution containing an organic solvent. However, since the above optical film is used in a visually recognized image display device, extremely strict quality is required for coating failures such as streaks during coating and drying unevenness. In particular, as the screen size of the image display device is increased, it becomes easy to recognize even a weak application failure, so that it is required that there is almost no application failure.

  By the way, a cellulose acylate film, particularly a cellulose triacetate film is generally used as the transparent support of the optical film. This cellulose acylate film is generally produced by a solution casting method or a melt casting method, but the solution casting method can produce a good film having higher flatness than the melt casting method. . For example, Patent Document 1 describes a method for producing a cellulose acylate film. For this reason, the solution casting method is generally employed in practice.

  Moreover, it is common to add a plasticizer to such a cellulose acylate film in order to control the flexibility and moisture permeability of the transparent support. Patent Document 2 describes a method for controlling the surface amount of such a plasticizer.

  In the cellulose acylate film as described above, since the cellulose acylate and the plasticizer have solubility in a solvent, when a coating layer with an organic solvent is directly applied on the cellulose acylate film, Influence of solubility and permeability. Patent Document 3 describes a method for controlling adhesion and optical properties by controlling the solvent species and ratios having different solubility in a support when an optical functional layer is applied to such a cellulose acylate film. Has been.

Japanese Patent Publication No. 5-17844 JP-A-8-57879 JP 2002-169001 A

When applying a coating solution containing an organic solvent to a cellulose acylate film containing a plasticizer as described above, the coating properties and drying are dependent on the affinity and solubility of the cellulose acylate and the plasticizer and the organic solvent. Affects sex.
The coating liquid usually contains components that form an optical functional layer and a physical functional layer. As a coating solvent, it is necessary to select a solvent having good solubility and stability of the contained components. In addition, when coating and processing using a coating solution containing an organic solvent, there are few problems with human health, ecosystem damage, and environmental safety from the viewpoint of the working environment and residual solvent in the finished optical film. It is necessary to select a solvent.
The purpose of the present invention is that when applying a coating solution containing an organic solvent on a cellulose acylate film, the stability of the coating solution is good, and the harmfulness and environmental burden due to the coating solvent are small. It is to provide a high-quality optical film with less coating failure.
Another object of the present invention is to provide a manufacturing method for forming such an optical film.
Still another object of the present invention is to provide a polarizing plate using the optical film.
Still another object of the present invention is to provide an image display device comprising the optical film or the polarizing plate.

（一般式１中、Ｒ ^１ は水素原子、メチル基、メトキシ基、無置換のアルコキシカルボニル基、シアノ基、フッ素原子、または塩素原子を表す。
Ｙは、単結合、＊−ＣＯＯ−＊＊、＊−ＣＯＮＨ−＊＊、または、＊−Ｏ−＊＊を表す。
Ｌは２価の連結鎖を表す。
Ｒ ^２ 〜Ｒ ^４ は、各々独立に、ハロゲン原子、水酸基、無置換のアルコキシ基、または無置換のアルキル基を表す。
Ｒ ^５ は水素原子、または無置換のアルキル基を表す。
Ｒ ^６ は置換もしくは無置換のアルキル基、置換もしくは無置換のアリール基を表す。
ｌはｌ＝１００−ｍの数式を満たす数を表し、ｍは０〜５０の数を表す。
なお、該加水分解物および／またはその部分縮合物は、特定のｌ及びｍを有する一般式１で表される化合物の複数種の混合物の加水分解物および／またはその部分縮合物であってもよい。）
〔９〕
上記〔１〕〜〔４〕、〔６〕〜〔８〕のいずれかに記載の光学フィルムが、偏光板における偏光子の２枚の保護フィルムのうちの一方に用いられていることを特徴とする偏光板。
〔１０〕
上記〔６〕〜〔８〕のいずれかに記載の光学フィルム、または上記〔９〕に記載の偏光板が、ディスプレイの最表面に用いられていることを特徴とする画像表示装置。
本発明は上記〔１〕〜〔１０〕に関するものであるが、参考のためその他の事項（例えば下記１〜１９に記載の事項など）についても記載した。
１．少なくとも１層の機能層が設けられている透明支持体の厚みムラが平均厚みの±５％以下であり、かつ該透明支持体の機能層塗布面側の表面可塑剤量のムラが表面可塑剤の平均可塑剤量の±２０％以下であることを特徴とする光学フィルム。
２．少なくとも１層の機能層が設けられている前記透明支持体の厚みムラが、長手方向１ｍ以上かつ幅方向１ｍ以上の範囲で平均膜みの±５％以下であり、前記透明支持体の機能層塗布面側の表面可塑剤量のムラが、長手１ｍ以上かつ幅方向１ｍ以上の範囲で表面可塑剤の平均残存量の±２０％以下であることを特徴とする光学フィルム。
３．前記透明支持体の平均厚みが２０μｍ以上１２０μｍ以下であることを特徴とする上記１または２に記載の光学フィルム。
４．前記透明支持体がセルローストリアセテートであることを特徴とする上記１〜３のいずれかに記載の光学フィルム。
５．前記少なくとも１層の機能層が低屈折率層であり、反射防止能を持つことを特徴とした上記１〜４のいずれかに記載の光学フィルム。
６．前記低屈折率層中に、平均粒径が該低屈折率層の厚みの３０％以上１５０％以下にあるシリカ微粒子が少なくとも１種含有されていることを特徴とする上記５に記載の反射防止フィルム。
７．前記低屈折率層中に含有されているシリカ微粒子の少なくとも１種が、中空のシリカ微粒子であり、該シリカ微粒子の屈折率が１．１７〜１．４０であることを特徴とする上記６に記載の反射防止フィルム。
８．前記低屈折率層のバインダーに含フッ素ポリマーを用いることを特徴とする上記５〜７に記載の反射防止フィルム。
９．前記含フッ素ポリマーが、含フッ素ビニルモノマー重合単位および側鎖に（メタ）アクリロイル基を有する重合単位を含み、主鎖が炭素原子のみからなる共重合体（Ｐ）であることを特徴とする上記８に記載の反射防止フィルム。
１０．共重合体（Ｐ）が下記一般式２で表されることを特徴とする上記９に記載の反射防止フィルム。
一般式２ As a result of intensive studies, the present inventor can control the coating amount and solvent permeability by using a transparent support having specific physical properties when applying a functional layer on the transparent support. It has been found that an optical film with good quality can be provided with few coating failures such as coating stripes and uneven drying.
According to the present invention, an optical film having the following constitution, a production method thereof, an antireflection film, a polarizing plate, and an image display device are provided, and the above object is achieved.
[1]
An optical film in which at least one functional layer is provided on a long transparent support, and the thickness unevenness of the transparent support is ± 5% or less of the average thickness. For a total of 25 points, the plasticizer amount is 3 to 10% by mass, and 5 points are equally spaced in the width direction of 1 m and 5 points in the longitudinal direction of 1 m on the functional layer coating surface side of the transparent support. An optical film characterized in that the variation in the measured amount of surface plasticizer is ± 20% or less of the average remaining amount of surface plasticizer.
Here, the surface plasticizer amount refers to the amount of plasticizer from the surface to 2 μm thickness calculated from the plasticizer absorption peak intensity ratio by ATR-IR measurement.
[2]
The thickness unevenness of the transparent support is within ± 5% of the average thickness in the range of 1 m or more in the longitudinal direction and 1 m or more in the width direction, and the variation in the amount of surface plasticizer on the functional layer application surface side of the support is longitudinal. The optical film as described in [1] above, which is within ± 20% of the average remaining amount of the surface plasticizer in the range of 1 m or more and 1 m or more in the width direction.
[3]
The optical film as described in [1] or [2] above, wherein the average thickness of the transparent support is from 20 μm to 120 μm.
[4]
The optical film as described in any one of [1] to [3] above, wherein the transparent support is cellulose triacetate.
[5]
After a cellulose acylate film having a plasticizer amount of 3 to 10% by mass is formed and the residual solvent amount of the cellulose acylate film is 5% by mass or less, a heat treatment at 100 ° C. to 160 ° C. is performed for 60 seconds or more. The optical film as described in [1] above, wherein the method is carried out for 900 seconds or less, and the cellulose acylate film is used as a transparent support, and at least one functional layer is coated on the transparent support. Production method.
[6]
The optical film as described in any one of [1] to [4] above, wherein at least one functional layer is a low refractive index layer and has antireflection ability.
[7]
Any one of [1] to [4] or [6] above, wherein a solvent that partially dissolves or swells the transparent support is used in the coating solution for forming at least one functional layer. Optical film.
[8]
[1] to [4], [6] above, wherein at least one functional layer contains a hydrolyzate of organosilane represented by the following general formula 1 and / or a partial condensate thereof: [7] The optical film according to any one of [7].
General formula 1

(In General Formula 1, R ¹ represents a hydrogen atom, a methyl group, a methoxy group, an unsubstituted alkoxycarbonyl group, a cyano group, a fluorine atom, or a chlorine atom.
Y represents a single bond, * -COO-**, * -CONH-**, or * -O-**.
L represents a divalent linking chain.
R ^{2 to} R ⁴ each independently represent a halogen atom, a hydroxyl group, an unsubstituted alkoxy group, or an unsubstituted alkyl group.
R ⁵ represents a hydrogen atom or an unsubstituted alkyl group.
R ⁶ represents a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group.
l represents a number satisfying the mathematical formula of l = 100−m, and m represents a number from 0 to 50.
The hydrolyzate and / or its partial condensate may be a hydrolyzate and / or its partial condensate of a mixture of a plurality of compounds represented by general formula 1 having specific l and m. Good. )
[9]
The optical film according to any one of [1] to [4] and [6] to [8] is used for one of two protective films of a polarizer in a polarizing plate. Polarizing plate.
[10]
An optical display according to any one of [6] to [8] or a polarizing plate according to [9] is used on the outermost surface of a display.
The present invention relates to the above [1] to [10], but other matters (for example, matters described in the following 1 to 19) are also described for reference.
1. The thickness unevenness of the transparent support provided with at least one functional layer is ± 5% or less of the average thickness, and the surface plasticizer amount unevenness of the surface of the transparent support on which the functional layer is applied An optical film characterized by being an average plasticizer amount of ± 20% or less.
2. The thickness unevenness of the transparent support provided with at least one functional layer is ± 5% or less of the average film thickness in the range of 1 m or more in the longitudinal direction and 1 m or more in the width direction, and the functional layer of the transparent support An optical film characterized in that the unevenness of the surface plasticizer amount on the coated surface side is within ± 20% of the average remaining amount of the surface plasticizer in the range of 1 m or more in the longitudinal direction and 1 m or more in the width direction.
3. 3. The optical film as described in 1 or 2 above, wherein the transparent support has an average thickness of 20 μm or more and 120 μm or less.
4). 4. The optical film as described in any one of 1 to 3 above, wherein the transparent support is cellulose triacetate.
5. 5. The optical film as described in any one of 1 to 4 above, wherein the at least one functional layer is a low refractive index layer and has antireflection ability.
6). 6. The antireflection according to 5 above, wherein the low refractive index layer contains at least one kind of silica fine particles having an average particle diameter of 30% to 150% of the thickness of the low refractive index layer. the film.
7). The above 6 characterized in that at least one kind of silica fine particles contained in the low refractive index layer is hollow silica fine particles, and the refractive index of the silica fine particles is 1.17 to 1.40. The antireflection film as described.
8). 8. The antireflection film as described in 5 to 7 above, wherein a fluorine-containing polymer is used for the binder of the low refractive index layer.
9. The fluorine-containing polymer is a copolymer (P) comprising a fluorine-containing vinyl monomer polymerization unit and a polymerization unit having a (meth) acryloyl group in a side chain, and the main chain consisting of only carbon atoms. 8. The antireflection film according to 8.
10. 10. The antireflection film as described in 9 above, wherein the copolymer (P) is represented by the following general formula 2.
General formula 2

In General Formula 2, L represents a linking group having 1 to 10 carbon atoms, and m represents 0 or 1. X represents a hydrogen atom or a methyl group. A represents a polymerization unit of any vinyl monomer, and may be a single component or a plurality of components. x, y, and z represent mol% of each constituent component, and represent values satisfying 30 ≦ x ≦ 60, 5 ≦ y ≦ 70, and 0 ≦ z ≦ 65.
11. 11. The optical film as described in any one of 1 to 10 above, wherein a solvent that partially dissolves or swells the transparent support is used in the coating liquid that forms the at least one functional layer.
12. The optical film as described in any one of 1 to 11 above, wherein at least one functional layer contains a hydrolyzate of organosilane represented by the following general formula 1 and / or a partial condensate thereof: .
General formula 1

(In General Formula 1, R ¹ represents a hydrogen atom, a methyl group, a methoxy group, an unsubstituted alkoxycarbonyl group, a cyano group, a fluorine atom, or a chlorine atom.
Y represents a single bond, * -COO-**, * -CONH-**, or * -O-**.
L represents a divalent linking chain.
R ^{2 to} R ⁴ each independently represent a halogen atom, a hydroxyl group, an unsubstituted alkoxy group, or an unsubstituted alkyl group.
R ⁵ represents a hydrogen atom or an unsubstituted alkyl group.
R ⁶ represents a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group.
l represents a number satisfying the mathematical formula of l = 100−m, and m represents a number from 0 to 50.
The hydrolyzate and / or its partial condensate may be a hydrolyzate and / or its partial condensate of a mixture of a plurality of compounds represented by general formula 1 having specific l and m. Good. )

13. The optical film as described in any one of 1 to 12 above, wherein any one of a hard coat layer, an antiglare layer, a light diffusion layer, and a high refractive index layer is provided as the at least one functional layer.
14 A high refractive index layer is provided as the at least one functional layer, and the high refractive index layer contains inorganic fine particles containing titanium dioxide as a main component and containing at least one element selected from cobalt, aluminum, and zirconium. 14. The optical film as described in 13 above, which is a constituent layer having a refractive index of 1.55 to 2.40.
15. The optical film in any one of said 1-14 is used for one of the two protective films of the polarizer in a polarizing plate, The polarizing plate characterized by the above-mentioned.
16. Of the two protective films of the polarizer, the film other than the antireflection film is an optical compensation film having an optical compensation layer comprising an optically anisotropic layer, and the optically anisotropic layer has a discotic structural unit. An angle formed by the disc surface of the discotic structural unit and the surface protective film surface, wherein the disc surface of the discotic structural unit is inclined with respect to the surface protective film surface. 16. The polarizing plate as described in 15 above, wherein is changed in the depth direction of the optically anisotropic layer.
17. 16 above, wherein at least one of the two protective films of the polarizer is a cellulose acylate film characterized by satisfying the following formulas (I) and (II): The polarizing plate as described.
(I): 0 ≦ Re (630) ≦ 10 and | Rth (630) | ≦ 25
(II): | Re (400) −Re (700) | ≦ 10 and | Rth (400) −Rth (700) | ≦ 35
18. 15. An image display device, wherein the optical film according to any one of 1 to 14 or the polarizing plate according to any one of 15 to 17 is used on an outermost surface of a display.
19. 18. A TN, STN, VA, IPS, or OCB mode transmissive, reflective, or transflective liquid crystal display device having at least one polarizing plate described in 15 to 17 above.

  The present invention provides a high-quality optical film with few coating failures such as coating stripes and drying unevenness. In addition, the present invention provides a method for forming an optical film in which the stability of the coating liquid is good, the harmfulness of the coating solvent and the environmental load are small, and coating failures such as coating stripes and drying unevenness are small.

The optical film of the present invention will be described in detail below.
The optical film of the present invention is an optical film having a process of directly applying a coating liquid containing an organic solvent on a support composed of a cellulose acylate film.
The optical film of the present invention, particularly the antireflection film, is excellent in scratch resistance while having sufficient antireflection properties. Further, the image display device provided with the optical film or antireflection film of the present invention, and the image display device provided with a polarizing plate using the optical film or antireflection film of the present invention are reflected in the reflection of external light and the reflection of the background. There is little dust and visibility is extremely high.
Hereinafter, the transparent support, the coating layer on the support, and other layers will be described in this order. In the present specification, the description “(numerical value A) to (numerical value B)” representing a physical property value means “(numerical value A) or more and (numerical value B) or less”.

<Transparent support>
A plastic film is preferably used as the transparent support of the optical film of the present invention. As the polymer forming the plastic film, cellulose acylate (eg, cellulose triacylate, cellulose diacylate, typically TAC-TD80U, TD80UF, etc. manufactured by Fuji Photo Film Co., Ltd.), polyamide, polycarbonate, polyester (eg, Polyethylene terephthalate, polyethylene naphthalate), polystyrene, polyolefin, norbornene resin (Arton: trade name, manufactured by JSR Corporation), amorphous polyolefin (Zeonex: trade name, manufactured by Nippon Zeon Corporation), and the like. Among these, cellulose triacylate, polyethylene terephthalate, and polyethylene naphthalate are preferable, and cellulose triacylate is particularly preferable.

The cellulose acylate film of the present invention is obtained by adding various additives to the following cellulose acylate and processing the film, and a functional layer can be formed on the film support by solution coating.

Examples of cellulose as a raw material for the cellulose acylate film used in the present invention include cotton linter, kenaf, wood pulp (hardwood pulp, conifer pulp), and any cellulose ester obtained from any raw material cellulose can be used. May be used.
In the present invention, cellulose acylate is produced by esterification from cellulose, and it is particularly preferable to use cellulose obtained by purifying linter, kenaf and pulp.

In the present invention, cellulose acylate is a carboxylic acid ester having 2 to 22 carbon atoms in total.
The acyl group having 2 to 22 carbon atoms of the cellulose acylate used in the present invention may be an aliphatic group or an aryl group, and is not particularly limited. They are, for example, alkyl carbonyl esters, alkenyl carbonyl esters, cycloalkyl carbonyl esters, aromatic carbonyl esters, aromatic alkyl carbonyl esters, etc. of cellulose, each of which may further have a substituted group. Among these, preferable acyl groups include acetyl, propionyl, butanoyl, heptanoyl, hexanoyl, octanoyl, decanoyl, dodecanoyl, tridecanoyl, tetradecanoyl, hexadecanoyl, octadecanoyl, cyclohexanecarbonyl, adamantanecarbonyl, oleoyl, Examples thereof include phenylacetyl, benzoyl, naphthylcarbonyl, cinnamoyl group and the like. Among these, more preferred acyl groups are acetyl, propionyl, butanoyl, pentanoyl, hexanoyl, cyclohexanecarbonyl, dodecanoyl, octadecanoyl, oleoyl, benzoyl, naphthylcarbonyl, cinnamoyl and the like.
The method for synthesizing cellulose acylate is described in detail on page 9 of JIII Journal of Technical Disclosure No. 2001-1745 (issued on March 15, 2001, Invention Association).

The cellulose acylate of the present invention preferably has a degree of substitution with a hydroxyl group of cellulose satisfying the following mathematical formulas (III) and (IV).
Formula (III): 2.3 ≦ SA ′ + SB ′ ≦ 3.0
Formula (IV): 0 ≦ SA ′ ≦ 3.0

  Here, SA ′ is the substitution degree of the acetyl group substituting the hydrogen atom of the hydroxyl group of cellulose, and SB ′ is the substitution degree of the acyl group having 3 to 22 carbon atoms substituting the hydrogen atom of the hydroxyl group of cellulose. Represents. SA represents an acetyl group substituting a hydrogen atom of a hydroxyl group of cellulose, and SB represents an acyl group having 3 to 22 carbon atoms substituting a hydrogen atom of a hydroxyl group of cellulose.

Glucose units having β-1,4 bonds constituting cellulose have free hydroxyl groups at the 2nd, 3rd and 6th positions. Cellulose acylate is a polymer obtained by esterifying some or all of these hydroxyl groups with acyl groups. The degree of acyl substitution means the proportion of cellulose esterified at each of the 2-position, 3-position and 6-position (100% esterification at each position is substitution degree 1).
In the present invention, the total sum of substitution degrees of SA and SB (SA ′ + SB ′) is more preferably 2.6 to 3.0, and particularly preferably 2.80 to 3.00.
Further, the degree of substitution (SA ′) of SA is more preferably 1.4 to 3.0, and particularly 2.3 to 2.9.

Furthermore, it is preferable that the following mathematical formula (V) is satisfied at the same time.
Formula (V): 0 ≦ SB ”≦ 1.2
Here, SB ″ represents a C 3 or C 4 acyl group substituting a hydrogen atom of a hydroxyl group of cellulose.
Further, SB ″ is preferably 28% or more of the substituent at the 6-position hydroxyl group, more preferably 30% or more is the substituent at the 6-position hydroxyl group, more preferably 31% or more, and particularly preferably 32% or more. It is also preferred that the substituent is a hydroxyl group at the 6-position. Furthermore, the sum of the substitution degrees of SA ′ and SB ″ at the 6-position of the cellulose acylate is 0.8 or more, more preferably 0.85 or more, A cellulose acylate film having a value of 0.90 or more can also be mentioned as a preferable example. These cellulose acylate films can produce a solution having a preferable solubility, and in particular, a non-chlorine organic solvent can produce a good solution.
The degree of substitution can be obtained by calculating the degree of binding of fatty acids bound to hydroxyl groups in cellulose. As a measuring method, it can measure based on ASTM D-817-91 and ASTM D-817-96.
The state of substitution of the acyl group with the hydroxyl group is measured by ¹³ C-NMR method.

  In the cellulose acylate film of the present invention, it is preferable that the polymer component constituting the film is substantially composed of cellulose acylate having the above definition. “Substantially” means 55% by mass or more (preferably 70% by mass or more, more preferably 80% by mass or more) of the total polymer components. The cellulose acylate may be used alone or in combination of two or more.

The degree of polymerization of the cellulose acylate preferably used in the present invention is a viscosity average degree of polymerization of 200 to 700, preferably 230 to 550, more preferably 230 to 350, and particularly preferably a viscosity average degree of polymerization of 240 to 320. The average degree of polymerization can be measured by Uda et al.'S intrinsic viscosity method (Kazuo Uda, Hideo Saito, Journal of Textile Society, Vol. 18, No. 1, pages 105-120, 1962). Further details are described in JP-A-9-95538.
The number average molecular weight Mn of the cellulose acylate is preferably in the range of 7 × 10 ^{4 to} 25 × 10 ⁴ , more preferably in the range of 8 × 10 ⁴ to 15 × 10 ⁴ . The ratio of the cellulose acylate to the mass average molecular weight Mw, Mw / Mn, is preferably 1.0 to 5.0, more preferably 1.0 to 3.0. In addition, the average molecular weight and molecular weight distribution of a cellulose ester can be measured using a high performance liquid chromatography, Mn and Mw can be calculated using this, and Mw / Mn can be calculated.

  As the cellulose acylate film used in the present invention, a cellulose acylate in a range satisfying the above-mentioned formulas (1) and (2) is preferably used.

[Plasticizer]
Next, the plasticizer used for the cellulose acylate film of the present invention will be described. The plasticizer is a component added to impart flexibility to the cellulose acylate film, improve dimensional stability, improve moisture resistance, and reduce curl. As the plasticizer used in the present invention, a plasticizer conventionally known as a plasticizer for cellulose acylate can be used. As these conventional plasticizers, for example, phosphate ester plasticizers, phthalate ester plasticizers, glycolate plasticizers and the like can be preferably used. For phosphate ester plasticizers, triphenyl phosphate, tricresyl phosphate, cresyl diphenyl phosphate, octyl diphenyl phosphate, diphenyl biphenyl phosphate, trioctyl phosphate, tributyl phosphate, etc. For phthalate ester plasticizers, diethyl phthalate, dimethoxy Ethyl phthalate, dimethyl phthalate, dioctyl phthalate, dibutyl phthalate, di-2-ethylhexyl phthalate, glycolate plasticizers may use butyl phthalyl butyl glycolate, ethyl phthalyl ethyl glycolate, methyl phthalyl ethyl glycolate, etc. it can. Further, the plasticizer is preferably kept stably and uniformly distributed in the film, and is preferably excellent in exudation and hardly hydrolyzed.

  It is also preferable to use an aliphatic polyhydric alcohol ester as the plasticizer of the present invention. The aliphatic polyhydric alcohol ester of the present invention is an ester of a dihydric or higher aliphatic polyhydric alcohol and one or more monocarboxylic acids.

(Aliphatic polyhydric alcohol)
The aliphatic polyhydric alcohol used in the present invention is a dihydric or higher alcohol and is represented by the following general formula (A).
Formula (A): R _1- (OH) _n
Here, R ₁ is an n-valent aliphatic organic group, n is a positive integer of 2 or more, and a plurality of OH groups each independently represents an alcoholic or phenolic hydroxyl group.
Examples of the n-valent aliphatic organic group include an alkylene group (eg, methylene group, ethylene group, trimethylene group, tetramethylene group, etc.), an alkenylene group (eg, ethenylene group, etc.), an alkynylene group (eg, ethynylene group, etc.), a cycloalkylene group. (For example, 1,4-cyclohexanediyl group) and alkanetriyl group (for example, 1,2,3-propanetriyl group). The n-valent aliphatic organic group includes those having a substituent (for example, a hydroxy group, an alkyl group, a halogen atom, etc.). n is preferably from 2 to 20.
Examples of preferable polyhydric alcohol include, for example, adonitol, arabitol, ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, 1,2-propanediol, 1,3-propanediol, dipropylene glycol, tripropylene glycol, 1 , 2-butanediol, 1,3-butanediol, 1,4-butanediol, dibutylene glycol, 1,2,4-butanetriol, 1,5-pentanediol, 1,6-hexanediol, hexanetriol, Examples thereof include galactitol, mannitol, 3-methylpentane-1,3,5-triol, pinacol, sorbitol, trimethylolpropane, trimethylolethane, xylitol and the like. In particular, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, sorbitol, trimethylolpropane, and xylitol are preferable.

(Monocarboxylic acid)
There is no restriction | limiting in particular as monocarboxylic acid in the polyhydric alcohol ester of this invention, Well-known aliphatic monocarboxylic acid, alicyclic monocarboxylic acid, aromatic monocarboxylic acid, etc. can be used. Use of an alicyclic monocarboxylic acid or aromatic monocarboxylic acid is preferred in terms of improving moisture permeability and retention. Examples of preferred monocarboxylic acids include the following, but the present invention is not limited thereto. As the aliphatic monocarboxylic acid, a fatty acid having a straight chain or side chain having 1 to 32 carbon atoms can be preferably used. The number of carbon atoms is more preferably 1-20, and particularly preferably 1-10. When acetic acid is contained, compatibility with the cellulose ester is increased, and it is also preferable to use a mixture of acetic acid and another monocarboxylic acid.
Preferred aliphatic monocarboxylic acids include acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, enanthic acid, caprylic acid, pelargonic acid, capric acid, 2-ethyl-hexanecarboxylic acid, undecylic acid, lauric acid, tridecylic acid , Saturated fatty acids such as myristic acid, pentadecylic acid, palmitic acid, heptadecylic acid, stearic acid, nonadecanoic acid, arachidic acid, behenic acid, lignoceric acid, serotic acid, heptacosanoic acid, montanic acid, melicic acid, laccelic acid, undecylenic acid, Examples thereof include unsaturated fatty acids such as oleic acid, sorbic acid, linoleic acid, linolenic acid and arachidonic acid. These may further have a substituent.

Examples of preferred alicyclic monocarboxylic acids include cyclopentane carboxylic acid, cyclohexane carboxylic acid, cyclooctane carboxylic acid, bicyclononane carboxylic acid, bicyclodecane carboxylic acid, norbornene carboxylic acid, adamantane carboxylic acid and other carboxylic acids or their Derivatives can be mentioned. Examples of preferred aromatic monocarboxylic acids include those in which an alkyl group is introduced into the benzene ring of benzoic acid such as benzoic acid and toluic acid, and two or more benzene rings such as biphenylcarboxylic acid, naphthalenecarboxylic acid, and tetralincarboxylic acid. The aromatic monocarboxylic acid which has, or those derivatives can be mentioned. Benzoic acid is particularly preferable.

(Polyhydric alcohol ester)
The molecular weight of the polyhydric alcohol ester used in the present invention is not particularly limited, but is preferably 300-1500, and more preferably 350-750. The larger one is preferable in terms of exudation, and the smaller one is preferable in terms of moisture permeability and compatibility with the cellulose ester.

The carboxylic acid in the polyhydric alcohol ester of the present invention may be one kind or a mixture of two or more kinds. Moreover, all the OH groups in the polyhydric alcohol may be esterified, or a part of the OH groups may be left as they are. Preferably, it has 3 or more aromatic rings or cycloalkyl rings in the molecule.
Examples of the polyhydric alcohol ester used in the present invention are shown below.

The plasticizer particularly preferred in the present invention is preferably a liquid having a boiling point of 200 ° C. or higher and a liquid at 25 ° C., or a solid having a melting point of 25 to 250 ° C. More preferred are plasticizers having a boiling point of 250 ° C. or higher and a liquid at 25 ° C. or a solid having a melting point of 25 to 200 ° C. When the plasticizer is a liquid, the purification is usually carried out by distillation under reduced pressure, but higher vacuum is preferable. In the present invention, it is particularly preferable to use a plasticizer having a vapor pressure at 200 ° C. of 1333 Pa or less. A compound having a vapor pressure of 667 Pa or less, more preferably 133 to 1 Pa is preferred.
In the present invention, particularly preferable plasticizers are phosphate ester plasticizers and aliphatic polyhydric alcohol ester plasticizers. More preferred are phosphate ester plasticizers.

The cellulose acylate film of the present invention preferably has a moisture permeability of 20 to 300 (g / m ² ; 24 h, 25 ° C., 90% RH), and 20 to 260 (g / m ² ; 24 h, 25 ° C., 90% RH). ) Is more preferable, and 20 to 200 (g / m ² ; 24 h, 25 ° C., 90% RH) is most preferable.

It is also preferable that the plasticizer of the present invention has a low exudation property. The exuding property refers to the property that the mass of the film is reduced by precipitation or volatilization of an additive such as a plasticizer outside the film in a high-temperature and high-humidity environment. After measuring the mass after standing for 1 day at 55% RH, the sample was left for 2 weeks under the conditions of 80 ° C. and 90% RH. The mass was measured and calculated by the following formula.
Exudability = {(sample mass before treatment−sample mass after treatment) / sample mass before treatment} × 100 (%)
The exudation property is preferably 2.0% or less, more preferably 1.0% or less, more preferably 0.5% or less, and further preferably 0.1% or less.

The type and amount of the plasticizer are determined from a comprehensive viewpoint such as physical properties such as flexibility, moisture permeability, oozing property, and adhesiveness of the film of the present invention. In the present invention, cellulose acylate is used. It was found that when the film was directly coated with an organic solvent, the coating property of the upper layer was greatly affected.
In the cellulose acylate film of the present invention, the amount of the plasticizer in the cellulose acylate is preferably 3 to 20% by mass, more preferably 5 to 15% by mass, and particularly preferably 5 to 12% by mass with respect to the total film. .

When coating the coating liquid directly on the cellulose acylate film containing the plasticizer of the present invention, unevenness in the amount of plasticizer on the surface of the coated film has a significant effect on the coating properties and drying properties when coating the coating solution. I found out that This is because the organic solvent component in the coating solution penetrates into the transparent support, and as a result, the coating property of the support during coating changes, and the drying of the coating solution is promoted by the penetration of the organic solvent component. Or, the coating surface unevenness changes due to the penetration of components of the coating film at the same time as the penetration of the solvent, etc., and influences on coating and drying unevenness due to the change in the aggregation state of the particle components in the coating film, etc. It is considered a thing. In any case, small unevenness in the surface plasticizer amount of the cellulose acylate film is effective for improving the coating and drying unevenness of the present invention.
The plasticizer content of the cellulose acylate film can be determined by methods such as infrared absorption spectroscopy (IR) and Fourier transform infrared absorption spectroscopy (FT-IR). This method is generally a method in which the strength of the IR absorption peak of the plasticizer and the IR absorption peak of the cellulose acylate are measured to determine the plasticizer / cellulose acylate ratio. For example, JP-A-8-57879, a plasticizer absorption peak (1390 cm ^-1), the intensity of the absorption peak (1470 cm ^-1) of the cellulose acylate was measured, is shown a method of determining the intensity ratio Yes. The content of the plasticizer can be determined by preparing a calibration curve using a sample in which the plasticizer / cellulose acylate ratio is changed.
Further, the amount of the surface plasticizer of the cellulose acylate is considered to be an amount of the plasticizer in the range of about 5 μm from the surface, particularly about 2 μm from the surface, which affects the coating property of the present invention. In order to measure the amount of plasticizer on the surface, a section of the film cross section is prepared, and the amount of plasticizer near the surface is measured by laser transmission IR (surface of about 10 μm), total reflection It can be measured by a method by IR measurement (ATR-IR) (surface to a range of about 2 μm). As the method for measuring the amount of surface plasticizer of the present invention, the amount of surface plasticizer is usually ATR-IR because it is used as a composition analysis of the surface and the composition in the range of about 0.2 to 2 μm from the surface is known. Shown in the measurement results. However, the amount of the plasticizer may be quantified by another type of measurement method. However, the amount of the surface plasticizer of the present invention is not defined by the amount of the plasticizer on the extreme surface (0.1 μm or less).

In the cellulose acylate film of the present invention, the amount of the surface plasticizer is preferably 1% by mass to 20% by mass. More preferably, it is 3 to 15% by mass, still more preferably 3 to 12% by mass, and particularly preferably 3 to 10% by mass.
In the present invention, the smaller the surface plasticizer amount unevenness (or variation), the better the tendency for coating unevenness and drying unevenness. The unevenness of the surface plasticizer amount is preferably ± 20% or less of the average residual amount. More preferably, it is ± 15% or less, and further preferably ± 10% or less.
In this case, “surface plasticizer amount unevenness (or variation)” is obtained by sampling a total of 25 points, 5 points at equal intervals in the width direction of 1 m and 5 points at equal intervals in the length direction of 1 m. The amounts are measured and preferably they are ± 20% or less of the average remaining amount.
The unevenness in the amount of the surface plasticizer increases as the area of the cellulose acylate film increases. However, in order to improve the coating and drying unevenness of the present invention, it is preferable that the unevenness of the surface plasticizer amount falls within the range of the above average residual amount in at least an area of 1 m or more in the longitudinal direction and 1 m or more in the width direction. . More preferably, it is within the range of the average remaining amount in an area of 10 m or more in the longitudinal direction and 1.2 m or more in the width direction.

  The unevenness in the amount of the surface plasticizer as described above can be changed by the amount of plasticizer added to the entire film, the casting method of the cellulose acylate film, the drying method during casting, and the drying method after casting. Specifically, the time from casting to peeling of the cellulose acylate film, the drying method, the heat treatment after film formation, the conveyance speed, and the like. These methods are described later in [Method for producing cellulose acylate film].

  In the present invention, it is also preferable that the amount of the plasticizer on the surface is smaller than the amount of the plasticizer in the entire film because the applicability can be improved while maintaining the flexibility of the film. This comparison of the amount of plasticizer can be confirmed by comparing the transmission IR of the film thickness with the surface IR. Such control of the amount of plasticizer is possible by the above-described casting and drying methods.

  The cellulose acylate film according to the present invention preferably contains hydrophobic fine particles in order to improve the mechanical strength and dimensional stability of the film and to improve moisture resistance. The primary average particle diameter of the fine particles is preferably 1 to 100 nm from the viewpoint of keeping the haze low, and the apparent specific gravity of the fine particles is preferably 70 g / liter or more. The addition amount of the fine particles is preferably 0.01 to 10 parts by mass, particularly 0.05 to 7 parts by mass with respect to 100 parts by mass of cellulose acylate.

Preferred specific examples of the fine particles include inorganic compounds such as silicon-containing compounds, silicon dioxide, titanium oxide, zinc oxide, aluminum oxide, barium oxide, zirconium oxide, strontium oxide, antimony oxide, tin oxide, tin oxide / antimony carbonate, Calcium, talc, clay, calcined kaolin, calcined calcium silicate, hydrated calcium silicate, aluminum silicate, magnesium silicate and calcium phosphate, ITO, zinc antimonate, etc. are preferred, more preferably inorganic compounds containing silicon and zirconium oxide However, since the haze increase of the cellulose acylate film can be suppressed, silicon dioxide is particularly preferably used.
The surface of the fine particles is preferably subjected to a hydrophobic treatment, and the surface treatment agent is preferably an organic compound having a polar group having an affinity for the surface of the fine particles or a coupling agent.

[Ultraviolet absorber]
The cellulose acylate film of the present invention contains an ultraviolet absorber for improving the light resistance of the film itself or for preventing deterioration of image display members such as a polarizing plate, a liquid crystal compound of an image display device, and an organic EL compound.
Use a UV absorber that has an excellent ability to absorb ultraviolet light with a wavelength of 370 nm or less from the viewpoint of preventing deterioration of the liquid crystal and absorbs as little visible light as possible with a wavelength of 400 nm or more from the viewpoint of good image display properties. Is preferred.
Examples include, but are not limited to, oxybenzophenone compounds, benzotriazole compounds, salicylic acid ester compounds, benzophenone compounds, cyanoacrylate compounds, nickel complex compounds, and the like.

Although the specific example as a ultraviolet absorber is listed below, this invention is not limited to these.
2- (2'-hydroxy-5'-methylphenyl) benzotriazole, 2- (2'-hydroxy-3 ', 5'-di-tert-butylphenyl) benzotriazole, 2- (2'-hydroxy-3) '-Tert-butyl-5'-methylphenyl) benzotriazole, 2- (2'-hydroxy-3', 5'-di-tert-butylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy -3 '-(3 ", 4", 5 ", 6" -tetrahydrophthalimidomethyl) -5'-methylphenyl) benzotriazole, 2,2-methylenebis (4- (1,1,3,3-tetramethyl) Butyl) -6- (2H-benzotriazol-2-yl) phenol), 2- (2'-hydroxy-3'-tert-butyl-5'-methylphenyl)- -Chlorobenzotriazole, 2,4-dihydroxybenzophenone, 2,2'-dihydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxy-5-sulfobenzophenone, bis (2-methoxy-4-hydroxy-5-benzoyl) Phenylmethane), (2,4-bis- (n-octylthio) -6- (4-hydroxy-3,5-di-tert-butylanilino) -1,3,5-triazine, 2 (2'-hydroxy- 3 ', 5'-di-tert-butylphenyl) -5-chlorobenzotriazole, (2 (2'-hydroxy-3', 5'-di-tert-amylphenyl) -5-chlorobenzotriazole, 2, 6-di-tert-butyl-p-cresol, pentaerythrityl-tetrakis [3- (3,5-di-tert- Til-4-hydroxyphenyl) propionate], triethylene glycol-bis [3- (3-tert-butyl-5-methyl-4-hydroxyphenyl) propionate], 1,6-hexanediol-bis [3- (3 , 5-di-tert-butyl-4-hydroxyphenyl) propionate], 2,4-bis- (n-octylthio) -6- (4-hydroxy-3,5-di-tert-butylanilino) -1,3 , 5-triazine, 2- (2'-hydroxy-4'-hexyloxyphenyl) -4,6-diphenyltriazine, 2,2-thio-diethylenebis [3- (3,5-di-tert-butyl -4-hydroxyphenyl) propionate], octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate Onate, N, N′-hexamethylenebis (3,5-di-tert-butyl-4-hydroxy-hydrocinnamide), 1,3,5-trimethyl-2,4,6-tris (3,5-di-) tert-butyl-4-hydroxybenzyl) benzene, tris- (3,5-di-tert-butyl-4-hydroxybenzyl) -isocyanurate, phenyl salicylate, p-tert-butyl salicylate, 2,4-dihydroxybenzophenone 2,2'-dihydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxy-5-sulfobenzophenone, bis (2-methoxy-4-hydroxy-5-benzoylphenylmethane 2'-ethylhexyl-2- Cyano-3,3-diphenyl acrylate, ethyl-2-cyano-3- (3 ', 4'- Etc. Chi dioxy phenyl) -2-acrylate.
Moreover, the ultraviolet absorber described in JP-A-6-148430 can also be preferably used.

Further, for example, hydrazine-based metal deactivators such as N, N′-bis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionyl] hydrazine and tris (2,4-di-tert A phosphorus processing stabilizer such as -butylphenyl) phosphite may be used in combination.
0.0001-1.0 mass part is preferable with respect to 100 mass parts of cellulose acylates, and, as for the addition amount of these stabilizer compounds, 0.001-0.1 mass part is still more preferable.

The ultraviolet absorber according to the present invention desirably has a transmittance of 20% or less at a wavelength of 370 nm, preferably 10% or less, more preferably 5% or less.
Two or more kinds of ultraviolet absorbers may be used. The ultraviolet absorber may be added to the dope after being dissolved in an organic solvent such as alcohol, methylene chloride, dioxolane, or directly in the dope composition. For an inorganic powder that does not dissolve in an organic solvent, a dissolver or a sand mill is used in the organic solvent and cellulose ester to disperse and then added to the dope.
In this invention, the usage-amount of a ultraviolet absorber is 0.1-15 mass parts with respect to 100 mass parts of cellulose acylates, Preferably it is 0.5-10 mass parts, More preferably, it is 0.8-7 mass parts. .

In addition, as the ultraviolet absorbent of the present invention, an ultraviolet absorbent polymer having less adverse effects such as poor adhesion due to precipitation and an increase in haze is also preferable. These are copolymerized polymers, and are a copolymer of an ultraviolet-absorbing monomer having an molar absorption coefficient at 380 nm of 4000 or more and an ethylenically unsaturated monomer, and the mass average molecular weight of the copolymer is 2000 to 2000. 20000 UV-absorbing copolymer is preferred in that it has less precipitation.
If the molar extinction coefficient at 380 nm is 4000 or more, it indicates that the ultraviolet absorption performance is good, and an effect sufficient to block the ultraviolet light is obtained, without the optical film itself being colored yellow, The transparency of the optical film is improved.

  As the ultraviolet absorbing monomer used in the ultraviolet absorbing copolymer in the present invention, a monomer having a molar extinction coefficient at 380 nm of 4000 or more, preferably 8000 or more, more preferably 10,000 or more is used. When the molar extinction coefficient at 380 nm is less than 4000, a large amount of addition is necessary to obtain the desired UV absorption performance, and the transparency is significantly lowered due to an increase in haze or precipitation of an ultraviolet absorber, and the film strength. The tendency to decrease is large.

Furthermore, the UV-absorbing monomer used in the UV-absorbing copolymer requires that the ratio of the molar extinction coefficient at 400 nm to the molar extinction coefficient at 380 nm is 20 or more. Largely unsuitable for optical film applications.
That is, in order to suppress absorption of light near 400 nm, which is closer to the visible range, and obtain desired UV absorption performance, it is preferable in the present invention to contain an ultraviolet absorbing monomer having high performance of absorbing ultraviolet light. .

a. UV-absorbing monomer Examples of the UV-absorbing monomer include salicylic acid-based UV absorbers (phenyl salicylate, p-tert-butyl salicylate, etc.) or benzophenone-based UV absorbers (2,4-dihydroxybenzophenone, 2,2'-dihydroxy-). 4,4'-dimethoxybenzophenone, etc.), benzotriazole ultraviolet absorbers (2- (2'-hydroxy-3'-tert-butyl-5'-methylphenyl) -5-chlorobenzotriazole, 2- (2 ' -Hydroxy-3 ', 5'-di-tert-butylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-3', 5'-di-tert-amyl-phenyl) benzotriazole and the like), Cyanoacrylate-based UV absorber (2'-ethylhexyl-2-sia -3,3-diphenyl acrylate, ethyl-2-cyano-3- (3 ', 4'-methylenedioxyphenyl) -acrylate, etc.), triazine ultraviolet absorbers (2- (2'-hydroxy-4' -Hexyloxyphenyl) -4,6-diphenyltriazine and the like, and compounds described in JP-A Nos. 58-185677 and 59-149350 are known.
As the ultraviolet absorbing monomer in the present invention, a basic skeleton is appropriately selected from various known types of ultraviolet absorbers as described above, and a substituent containing an ethylenically unsaturated bond is introduced. It is preferable to select and use a polymerizable compound having a molar extinction coefficient at 380 nm of 4000 or more. As the ultraviolet absorbing monomer of the present invention, a benzotriazole compound is preferably used from the viewpoint of storage stability.

  A particularly preferred ultraviolet absorbing monomer is represented by the following general formula 3.

General formula 3

In General Formula 3, R ¹¹ represents a halogen atom, or a group that substitutes on the benzene ring via an oxygen atom, a nitrogen atom, or a sulfur atom, and R ¹² represents a hydrogen atom, an aliphatic group, an aromatic group, Or R ¹³ , R ¹⁵ , and R ¹⁶ each independently represents a hydrogen atom, an aliphatic group, an aromatic group, or a heterocyclic group, and R ¹⁴ represents an oxygen atom or a nitrogen atom. Represents a substituent on the benzene ring. However, any one of the groups represented by R ¹¹ to R ¹⁶ has a group having the following structure as a partial structure. n represents an integer from 1 to 4.

In the above structure, L represents a divalent linking group, and R ¹ represents a hydrogen atom or an alkyl group.

  Although the preferable ultraviolet-absorbing monomer used by this invention is illustrated below, it is not limited to these.

b. Polymer A preferable UV-absorbing copolymer used in the present invention is a copolymer of the UV-absorbing monomer and the ethylenically unsaturated monomer, and the copolymer has a mass average molecular weight of 2000 to 20000. Preferably, it is 7000-15000.
In the case of a homopolymer of a UV-absorbing monomer, the haze is remarkably increased and the transparency is greatly reduced, so that it is not suitable for optical film applications. In addition, the homopolymer of the UV-absorbing monomer has low solubility in a solvent and is inferior in workability when forming a film. In addition, when the mass average molecular weight is in the above range, the compatibility with the resin is good, and there is no oozing or coloring on the film surface even over time.

  Examples of the ethylenically unsaturated monomer copolymerizable with the ultraviolet absorbing monomer include methacrylic acid and ester derivatives thereof (methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, i-butyl methacrylate, methacrylic acid). t-butyl, octyl methacrylate, cyclohexyl methacrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, tetrahydrofurfuryl methacrylate, benzyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, etc.), or Acrylic acid and its ester derivatives (methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, i-butyl acrylate, t-butyl acrylate, octyl acrylate Cyclohexyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, tetrahydrofurfuryl acrylate, 2-ethoxyethyl acrylate, diethylene glycol ethoxylate acrylate, 3-methoxybutyl acrylate, benzyl acrylate, Dimethylaminoethyl acrylate, diethylaminoethyl acrylate, etc.), alkyl vinyl ether (methyl vinyl ether, ethyl vinyl ether, butyl vinyl ether, etc.), alkyl vinyl ester (vinyl formate, vinyl acetate, vinyl butyrate, vinyl caproate, vinyl stearate, etc.), Examples include acrylonitrile, vinyl chloride, and styrene.

Among these ethylenically unsaturated monomers, an acrylic acid ester having a hydroxyl group or an ether bond, or a methacrylic acid ester (for example, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, tetrahydrofurfuryl methacrylate, acrylic acid 2 -Hydroxyethyl, 2-hydroxypropyl acrylate, tetrahydrofurfuryl acrylate, 2-ethoxyethyl acrylate, diethylene glycol ethoxylate acrylate, 3-methoxybutyl acrylate) are preferred. These may be used alone or in combination of two or more to be copolymerized with the ultraviolet absorbing monomer.
The use ratio of the ethylenically unsaturated monomer copolymerizable with the ultraviolet absorbing monomer is the compatibility between the obtained ultraviolet absorbing copolymer polymer and the transparent resin, the transparency and mechanical strength of the optical film, the desired ultraviolet ray. It is selected in consideration of the absorption performance, the addition amount of the copolymer polymer and the haze increase, the solubility of the copolymer polymer in the solvent, and the like. Preferably, both are blended so that the UV-absorbing monomer is contained in the copolymer in an amount of 20 to 70% by mass, more preferably 30 to 60% by mass.

  As a method for polymerizing the ultraviolet-absorbing copolymer in the present invention, conventionally known methods can be widely employed, and examples thereof include radical polymerization, anionic polymerization, and cationic polymerization. Examples of the initiator for the radical polymerization method include azo compounds and peroxides, and examples thereof include azobisisobutyronitrile (AIBN), azobisisobutyric acid diester derivatives, and benzoyl peroxide. The polymerization solvent is not particularly limited. For example, aromatic hydrocarbon solvents such as toluene and chlorobenzene, halogenated hydrocarbon solvents such as dichloroethane and chloroform, ether solvents such as tetrahydrofuran and dioxane, and amide solvents such as dimethylformamide. And alcohol solvents such as methanol, ester solvents such as methyl acetate and ethyl acetate, ketone solvents such as acetone, cyclohexanone and methyl ethyl ketone, and water solvents. Depending on the selection of the solvent, solution polymerization that polymerizes in a homogeneous system, precipitation polymerization that precipitates the produced polymer, and emulsion polymerization that polymerizes in a micelle state can also be performed.

  The mass average molecular weight of the ultraviolet-absorbing copolymer 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 50 to 100 ° C.

The ultraviolet-absorbing copolymer is preferably mixed at a rate of 0.01 to 40% by mass, more preferably 0.5 to 10% by mass with respect to cellulose acylate. At this time, the haze is not particularly limited as long as the haze when the optical film is formed is 0.5 or less, but the haze is preferably 0.2 or less. More preferably, the haze when the optical film is formed is 0.2 or less, and the transmittance at 380 nm is 10% or less.
In addition, the ultraviolet-absorbing copolymer can be used together with other low-molecular compounds, high-molecular compounds, inorganic compounds, etc., if necessary, when mixed with a transparent resin. For example, the UV-absorbing copolymer polymer and other low-molecular UV absorbers may be mixed with the transparent resin at the same time, and additives such as antioxidants, plasticizers and flame retardants may be mixed at the same time. preferable.

(Other additives)
Furthermore, in the cellulose acylate composition of the present invention, other various additives (for example, deterioration inhibitors (for example, antioxidants, peroxide decomposition agents, radical inhibitors, Metal deactivators, acid scavengers, amines, etc.), optical anisotropy control agents, release agents, antistatic agents, infrared absorbers, etc.) may be added, and these may be solid or oily. That is, the melting point and boiling point are not particularly limited. As the infrared absorbing dye, for example, those described in JP-A-2001-194522 are used.
These additives may be added at any time in the dope preparation process, but may be added to the final preparation process of the dope preparation process by adding the preparation process. Furthermore, the amount of each material added is not particularly limited as long as the function is manifested. Moreover, when a cellulose acylate film is formed from a multilayer, the kind and addition amount of the additive of each layer may differ. For example, although it describes in Unexamined-Japanese-Patent No. 2001-151902 etc., these are techniques conventionally known. Furthermore, for these details, materials described in detail on pages 16 to 22 in the Invention Association Public Technical Bulletin No. 2001-1745 (issued March 15, 2001, Invention Association) are preferably used. The amount of these additives to be used is preferably suitably used in the range of 0.001 to 20% by mass in the entire cellulose acylate composition.

The thickness of the transparent support of the present invention is generally 20 to 120 μm, preferably 25 to 80 μm, more preferably 30 to 60 μm. When the thickness is in the above range, the cutting of the support and the generation of wrinkles during production are suppressed, the polarizing plate and the display device are thinned, and further, the optical properties, cost, productivity, processing efficiency, etc. are excellent.
Further, the thickness unevenness is within ± 5% of the average thickness, preferably within ± 4%, and more preferably within ± 3%. Within this variation, the support thickness is excellent without substantially affecting the antireflection property of the support.
In order to make the thickness unevenness within ± 5%, (1) it does not contain a low molecular weight substance (oligomer) of cellulose acylate, and (2) a composition mainly composed of cellulose acylate for forming the polymer film. Adjusting the concentration and viscosity when casting a solution (dope) dissolved in an organic solvent, (3) Adjusting the drying temperature of the film surface in the drying process, the air volume when using the drying air, the wind direction, etc. Etc. are effective. The dissolution step, the casting step and the drying step are described in [Method for producing cellulose acylate film] described later.
The transparent support of the present invention is preferably in the form of a long roll having a length of 100 to 5000 m and a width of 0.7 to 2 m. When the transparent support is in the form of a roll, the optical film, antireflection film, polarizing plate protective film and image display device of the present invention are thinned and lightened, and the transmittance and the brightness are improved by improving the contrast and the like. Good optical characteristics can be stably obtained, and a long and wide support can be handled with good handling properties without causing problems such as wrinkles.
The thickness unevenness of the transparent support described above increases as the area of the cellulose acylate film increases. However, in order to improve the coating and drying unevenness of the present invention, the thickness unevenness preferably falls within the above range of the average thickness in an area of at least 1 m in the longitudinal direction and 1 m or more in the width direction. More preferably, the average thickness is within the range of 10 m or more in the longitudinal direction and 1.2 m or more in the width direction.
The cellulose acylate film used in the present invention preferably has a curl value in the width direction of -7 / m to + 7 / m. Particularly preferred is -5 / m to + 5 / m. When installing a coating layer to be described later on a long and wide cellulose acylate film, if the curl value in the width direction of the film is within the above-mentioned range, the film is handled easily and the film is cut. Will not occur. Also, at the edge and center of the film, the film will come into strong contact with the transport rolls to generate dust, and foreign matter will not adhere to the film. It can be within the allowable range. In addition, by setting the curl to the above range, bubbles can be prevented from entering when the polarizing film is bonded.
The curl value can be measured according to a measurement method (ANSI / ASCPH1.29-1985) defined by the American National Standards Institute.

[Method for producing cellulose acylate film]
The cellulose acylate film used as the support of the present invention is preferably produced by a solution casting method (solvent casting method). In the solution casting method, a solution in which the cellulose acylate or the like is dissolved in an organic solvent (dope ).

(Solution preparation process)
The organic solvent used in the solution casting method is not particularly limited as long as it is an organic solvent usually used in the solution casting method. For example, a solubility parameter in the range of 17 to 22 is preferable. Specifically, a lower aliphatic hydrocarbon chloride, a lower aliphatic alcohol, a ketone having 3 to 12 carbon atoms, an ester having 3 to 12 carbon atoms, an ether having 3 to 12 carbon atoms, and the number of carbon atoms Examples thereof include aliphatic hydrocarbons having 5 to 8 and aromatic hydrocarbons having 6 to 12 carbon atoms.
The ether, ketone and ester may have a cyclic structure. A compound having two or more functional groups of ether, ketone and ester (that is, —O—, —CO— and —COO—) can also be used as the organic solvent. Furthermore, the organic solvent may have another functional group such as an alcoholic hydroxyl group. In the case where the organic solvent is an organic solvent having two or more types of functional groups, the number of carbon atoms may be within the range of the above-mentioned preferable carbon number of the compound having any functional group.
Specifically, for example, compounds described in detail in the above-mentioned public technical number 2001-1745 p12-16 can be mentioned.

  Specific examples of organic solvents that dissolve cellulose acylate include hydrocarbons (eg, benzene, toluene), halogenated hydrocarbons (eg, methylene chloride, chlorobenzene), alcohols (eg, methanol, ethanol, diethylene glycol), Examples include ketones (eg, acetone), esters (eg, methyl acetate, ethyl acetate, propyl acetate) and ethers (eg, tetrahydrofuran, methyl cellosolve).

Of these, halogenated hydrocarbons having 1 to 7 carbon atoms are preferably used, and methylene chloride is particularly preferably used. In addition to methylene chloride, one kind of alcohol having 1 to 5 carbon atoms, from the viewpoint of physical properties such as solubility of cellulose acylate, peelability from the support, mechanical strength of the film, and further optical properties, It is preferable to mix several types. 2-25 mass% is preferable with respect to the whole solvent, and, as for content of alcohol, 5-20 mass% is more preferable. Specific examples of the alcohol include methanol, ethanol, n-propanol, isopropanol, n-butanol, etc., but methanol, ethanol, n-butanol, or a mixture thereof is preferably used.

  Technically, halogenated hydrocarbons such as methylene chloride can be used without problems, but from the viewpoint of the global environment and working environment, the organic solvent preferably does not substantially contain halogenated hydrocarbons. “Substantially free” means that the proportion of halogenated hydrocarbon in the organic solvent is less than 5% by mass (preferably less than 2% by mass). Moreover, it is preferable that halogenated hydrocarbons such as methylene chloride are not detected at all from the produced cellulose acylate film.

Such non-chlorine-based solvents include those described in paragraphs [0021] to [0025] of JP-A No. 2002-146043, paragraph numbers [0016] to [0021] of JP-A No. 2002-146045, and the like. An example is given.
The non-chlorine solvent is a mixed solvent of at least one organic solvent selected from ethers, ketones and esters having 3 to 12 carbon atoms and an alcohol, wherein the alcohol content in the previous solvent is A mixed solvent of 2 to 40% by mass is preferred.
An aromatic or aliphatic hydrocarbon having 5 to 10 carbon atoms may be added to the mixed solvent in an amount of 0 to 10 vol%. Examples of the hydrocarbon include cyclohexane, hexane, benzene, toluene and xylene.
In particular, it is preferable to use a mixed solvent in which two or more kinds of organic solvents are mixed, and particularly preferably, three or more kinds of mixed solvents different from each other, wherein the first solvent is a ketone having 3 to 4 carbon atoms and The ester having 3 to 4 carbon atoms or a mixture thereof, the second solvent is selected from ketones having 5 to 7 carbon atoms or acetoacetate, and the boiling point is 30 to 170 ° C. as the third solvent. Are preferably selected from alcohols having a boiling point of 30 to 170 ° C.
In particular, a mixed solvent of acetate, ketone and alcohol is used, which is a mixture of 20 to 90% by mass of acetate, 5 to 60% by mass of ketone, and 5 to 30% by mass of alcohol. It is preferable from the viewpoint of the solubility of cellulose acylate.
The blending ratio of the alcohols in the mixed solvent is preferably 2 vol% or more and 40 vol% or less, more preferably 3 vol% or more and 30 vol% or less, and further preferably 5 vol% or more and 20 vol% or less in the total solvent.

  The alcohol is preferably a monoalcohol or dialcohol having 1 to 8 carbon atoms or a fluoroalcohol having 2 to 10 carbon atoms, more preferably methanol, ethanol, 1-propanol, 2-propanol, 1- Butanol, 2-butanol, tert-butanol, 1-pentanol, 2-methyl-2-butanol, cyclohexanol, ethylene glycol, 2-fluoroethanol, 2,2,2-trifluoroethanol, 2,2,3 3-tetrafluoro-1-propanol is mentioned. These may be added alone or in admixture of two or more.

In addition to the above organic solvent, the dope may contain fluoroalcohol in an amount of 10% by mass or less, more preferably 5% by mass or less of the total organic solvent amount, thereby improving the transparency of the film or increasing the solubility. Is preferable. Examples of the fluoroalcohol include compounds described in paragraph No. [0020] of JP-A-8-143709 and paragraph No. [0037] of JP-A-11-60807. These fluoroalcohols may be used alone or in combination.
In the present invention, when preparing the dope, the container may be filled with an inert gas such as nitrogen gas.
Further, the viscosity of the dope just before film formation may be in a range where casting can be performed, and is usually adjusted to a range of 10 ps · s to 2000 ps · s, particularly 30 ps · s to 400 ps. -The range of s is preferable.

Regarding the preparation of the dope, the dissolution method is not particularly limited, and may be a room temperature dissolution method, a cooling dissolution method or a high temperature dissolution method, or a combination thereof. With respect to these, for example, JP-A-5-163301, JP-A-61-106628, JP-A-58-127737, JP-A-9-95544, JP-A-10-95854, JP-A-10-95854 -45950, JP-A-2000-53784, JP-A-11-322946, JP-A-11-322947, JP-A-2-276830, JP-A-2000-273239, JP-A-11-. JP-A No. 71463, JP-A No. 04-259511, JP-A No. 2000-273184, JP-A No. 11-323017, JP-A No. 11-302388, and the like. The method for dissolving the raw material polymer of the support described in the above in the organic solvent is appropriately used in the present invention. It can be applied to the technology. Furthermore, when a cellulose acylate is used as the polymer, the cellulose acylate dope solution is usually concentrated and filtered. Similarly, the above-mentioned Kokai No. 2001-1745 p. 25 in detail. In addition, when making it melt | dissolve at high temperature, the case where it is more than the boiling point of the organic solvent to be used is almost, and in that case, it uses in a pressurized state.
Further, the dope contains the plasticizer, the fine particles, and, if necessary, other additives such as a retardation adjusting agent and an ultraviolet absorber.

(Method of adding and mixing fine particles)
When adding the fine particles to the cellulose acylate solution, it is important that the coarse particles as described above do not exist and that the particles are stably dispersed so as not to cause aggregation or precipitation. For example, a desired cellulose acylate solution can be obtained without any particular limitation. A method of mixing and dispersing the fine particles in the dope after preparing a dispersion separately from the dope adjustment is preferable.
Additives other than the above fine particles may be added, for example, at the stage of mixing the cellulose acylate and the solvent, or the additive may be added after preparing a mixed solution with the cellulose acylate and the solvent. Further, it may be added and mixed immediately before casting the dope, which is a so-called immediately preceding addition method, and the mixing is used by installing screw-type kneading online. Mixing of these additives may be performed by adding the additive itself, but it may be dissolved in advance using a solvent or binder (preferably cellulose acylate) or may be dispersed and stabilized as the case may be. Use is also a preferred embodiment.

(Film forming process)
Next, a method for producing a film using a dope in the present invention will be described. As a method and equipment for producing a cellulose acylate film, a conventionally known solution casting film forming method and solution casting film forming apparatus called a drum method or a band method used for cellulose acylate film production can be used. .
Explaining the film forming process, a dope (cellulose acylate solution) prepared from a dissolving machine (kettle) is temporarily stored in a storage kettle, and the foam contained in the dope is defoamed for final preparation. It is important to remove aggregates and foreign matters from the prepared dope by microfiltration. Specifically, it is preferable to use a filter having a pore diameter as small as possible within a range in which components in the dope solution are not removed. For the filtration, a filter having an absolute filtration accuracy of 0.1 to 100 μm is used, and a filter having an absolute filtration accuracy of 0.1 to 25 μm is preferably used. The thickness of the filter is preferably 0.1 to 10 mm, and more preferably 0.2 to 2 mm. In that case, the filtration pressure is 15 kgf / cm ² or less, more preferably 10 kgf / cm ² or less,
Furthermore, it is preferable to filter at ² kgf / cm ² or less.

In addition, for microfiltration, it is also preferable to perform filtration several times while sequentially reducing the pore size of the filter.
The type of filter medium for microfiltration is not particularly limited as long as it has the above performance, and examples thereof include a filament type, a felt type, and a mesh type. The material of the filter medium for finely filtering the dispersion is not particularly limited as long as it has the above performance and does not adversely affect the coating solution. Examples thereof include stainless steel, polyethylene, polypropylene, and nylon.

  The prepared dope is fed from the dope discharge port to the pressure die through a pressure metering gear pump capable of delivering a constant amount of liquid with high accuracy, for example, by the rotational speed, and the dope is run endlessly from the die (slit) of the pressure die. The dope film (also referred to as a web) is peeled off from the metal support at the peeling point where the metal support has been cast evenly on the metal support and the metal support has substantially gone around. Both ends of the obtained web are sandwiched between clips, transported by a tenter while keeping the width, dried, then transported by a roll group of a drying device, dried, and wound up to a predetermined length by a winder. The combination of the tenter and the roll group dryer varies depending on the purpose.

  The metal support used in the casting step preferably has an arithmetic average roughness (Ra) of 0.015 μm or less and a ten-point average roughness (Rz) of 0.05 μm or less. More preferably, the arithmetic average roughness (Ra) is 0.001 to 0.01 μm, and the ten-point average roughness (Rz) is 0.001 to 0.02 μm. More preferably, the (Ra) / (Rz) ratio is 0.15 or more. Thus, by setting the surface roughness of the metal support within a predetermined range, the web can be easily and uniformly peeled from the metal support, and the surface shape of the film after film formation can be controlled within the scope of the present invention. .

About each of these manufacturing processes (Categorized into casting (including co-casting), drying, peeling, stretching, etc.), the above-mentioned public technical numbers No. 2001-1745, p. The process described in detail in 25-30 is preferred. In the casting process, one kind of dope may be cast as a single layer, or two or more kinds of dopes obtained by dissolving different polymers may be co-cast by simultaneous or sequential means. .
In the step of casting the cellulose acylate solution, the solution temperature is preferably −10 to 57 ° C. Moreover, when casting the said cellulose acylate solution, it is preferable that the temperature of the process is kept at -10-57 degreeC. Furthermore, the metal support for casting the cellulose acylate solution preferably has a surface temperature of -20 to 40 ° C.

In particular, in the step of forming a film from a dope comprising the composition as described above, a drying step is important in order to carry out the added compound without aggregation or uneven distribution.
The drying of the dope on the support is generally performed by applying hot air from the surface side of the support (drum or belt), that is, the surface of the web on the support, or applying hot air from the back of the drum or belt, There is a liquid heat transfer method in which the temperature controlled liquid is contacted from the back side opposite to the belt or drum dope casting surface and the drum or belt is heated by heat transfer to control the surface temperature. The method is preferred. The surface temperature of the support before casting may be any number as long as it is not higher than the boiling point of the solvent used for the dope. However, in order to promote drying and to lose fluidity on the support, the temperature may be set to 1 to 10 ° C lower than the boiling point of the lowest boiling solvent used. preferable.

The drying temperature in the drying step of the cellulose acylate film to obtain a film by drying the dope cast in a band shape is preferably 5 to 250 ° C, particularly preferably 20 to 180 ° C. Further, in order to remove the residual solvent, it is preferably used to dry at 30 to 160 ° C., and in that case, the residual solvent is evaporated by drying with high-temperature air whose temperature is changed successively. The above method is described in Japanese Patent Publication No. 5-17844. According to this method, it is possible to shorten the time from casting to stripping. The drying temperature, the amount of drying air, and the drying time vary depending on the solvent used, and may be appropriately selected according to the type and combination of the solvents used.
The amount of residual solvent in the final finished film is preferably 2% by mass or less, and more preferably 0.4% by mass or less in order to obtain a film having good dimensional stability. In the present invention, the stripping time can be further shortened with a stripping agent, and the resistance at the time of stripping is reduced, so that the surface shape (such as unevenness in the lateral direction during stripping, unevenness due to gel residue) is eliminated. Can be obtained.

Specifically, the average drying speed from dope casting to stripping is preferably more than 300 mass% / min and 1000 mass in consideration of maintaining good productivity and suppressing the occurrence of wind unevenness. % / Min or less, more preferably more than 400% by mass / min and 900% by mass / min or less, most preferably more than 500% by mass / min and 800% by mass / min or less.
The average drying speed is a value obtained by dividing the amount of change in the solvent content of the casting dope by the time.
To adjust the average drying speed, the temperature of the drying air, the air volume, the concentration of the solvent gas, the surface temperature of the casting support, the temperature of the casting dope, the wet thickness of the casting dope, the solvent of the casting dope It can be performed by appropriately adjusting the composition and the like.

(Peeling process)
In this step, the web in which the solvent is evaporated on the metal support is peeled off at the peeling position. The peeled web is sent to the next process. If the residual solvent amount of the web at the time of peeling (the following formula) is too large, peeling will be difficult, or conversely, if it is peeled off after sufficiently drying on the metal support, part of the web will be peeled off in the middle . There is a gel casting method (gel casting) as a method for increasing the film forming speed (the film forming speed can be increased because the film is peeled off while the residual solvent amount is as large as possible). For example, a poor solvent for the cellulose ester is added to the dope, and the dope is cast and then gelled, and the temperature of the metal support is lowered to gel. By gelling on a metal support and increasing the strength of the film at the time of peeling, peeling can be accelerated and the film forming speed can be increased. The amount of residual solvent after peeling can be determined according to the strength of the drying condition of the web on the metal support, the length of the metal support, and the like.
It is preferable to peel in the range of 5-400 mass% of the residual solvent amount of the web in this peeling position. Furthermore, it is preferable to set it as 10-350 mass%. In the case of peeling at a time when the amount of residual solvent is larger, if the web is too soft, flatness at the time of peeling is impaired, and slippage and vertical stripes due to peeling tension are likely to occur.
In the present invention, the peeling residual solvent amount can be expressed by the following equation.

Residual solvent amount (% by mass) = {(MN) / N} × 100
Here, M is the mass of the web at any point in time, and N is the mass after drying the web of M mass at 110 ° C. for 3 hours.
Further, the time until the web is peeled from the metal support is preferably 1 second or more and 120 seconds or less. More preferably, it is 2 seconds or more and 100 seconds or less, and particularly preferably 3 seconds or more and 90 seconds or less. The shorter the time, the higher the casting speed and the higher the productivity, but the web becomes difficult to handle.
In the drying process after peeling from the support, the film tends to shrink in the width direction by evaporation of the solvent. Shrinkage increases with drying at higher temperatures. In order to improve the flatness of the finished film, it is preferable to dry while suppressing the shrinkage as much as possible. From this point, for example, a method of drying the entire drying process or a part of the process as shown in Japanese Patent Application Laid-Open No. 62-46625 while holding the width at both ends of the web with a clip in the width direction (tenter method) )
Is preferred.

  In the present invention, the casting speed is preferably 10 to 200 m / min.

(Drying and stretching process)
After peeling, the web is generally dried using a drying device that alternately conveys the web through rolls arranged in a staggered manner, a tenter device that clips and conveys both ends of the web with clips, or both devices. As a drying means, hot air is generally blown on both sides of the web, but there is also a means for heating by applying a microweb instead of the wind. Too much drying tends to impair the flatness of the finished film. Throughout, the drying temperature is usually in the range of 40 to 250 ° C. More preferably, it is 40-180 degreeC. The drying temperature, the amount of drying air, and the drying time differ depending on the solvent used, and the drying conditions may be appropriately selected according to the type and combination of the solvents used.
Finally, it is preferable to dry under the condition that the residual solvent amount in the finished cellulose acylate film is in the range of 0.01 to 1.5% by mass. More preferably, it is 0.01-1.0 mass%.

  The casting and drying processes as described above are basically set according to the casting method, casting speed, stripping method, surface quality, etc. The amount of plasticizer on the surface can be changed. Specifically, in order to reduce the amount of plasticizer on the surface, promoting drying on the metal support during casting, peeling off the metal support quickly, as disclosed in JP-A-8-57879 There is a method of performing a heat treatment at a temperature of 100 to 160 ° C. after the residual solvent of the film becomes 5% by mass or less. Also, since the surface not in contact with the metal support during casting tends to be delayed in drying, the surface plasticizer amount tends to be large, and the surface not in contact with the metal support tends to have a small amount of surface plasticizer. The surface that is not in contact with the film can be used for coating, but since it is not in contact with the metal support, the surface quality may be deteriorated due to the flatness of the film. Among the methods for changing the amount of the surface plasticizer as described above, the method of performing heat treatment at 100 ° C. to 160 ° C. is particularly preferable because the amount of the surface plasticizer can be lowered while maintaining the total amount of the plasticizer. Such a heat treatment temperature is preferably 120 ° C. or higher and 150 ° C. or lower. The heat treatment time is preferably 30 seconds or more and 1200 seconds or less, more preferably 60 seconds or more and 900 seconds or less, and particularly preferably 120 seconds or more and 600 seconds or less.

(Stretching process)
The cellulose acylate film is preferably stretched by 0.5 to 300% at least during uniaxial casting or after casting.
In the casting step, it is preferable to perform uniaxial stretching only in one direction such as the casting direction (longitudinal direction) or biaxial stretching in the casting direction and the other direction (lateral direction).
By stretching the produced cellulose acylate film, it is possible to adjust the mechanical strength and further the optical properties (retardation value) of the film. At this time, the draw ratio is preferably 3 to 100%.
When the following (1) or (2) or both stretching methods are employed, the flatness of the film, the strength of the film, the optical characteristics, etc. can be adjusted within a predetermined range.
(1) The film is stretched in the width direction at a stretching ratio of 3 to 40%, more preferably 7 to 38%, and still more preferably 15 to 35%. Subsequently, treatment is performed at 20 to 160 ° C. while expanding in the longitudinal direction from 0.4% to 5%, more preferably from 0.7% to 4%, and even more preferably from 1% to 3.5%.
(2) A temperature difference is given to the front and back during stretching. The temperature of the surface in contact with the substrate (band or drum) at the time of casting is higher by 2 ° C. or higher and 20 ° C. or lower, more preferably 3 ° C. or higher and 15 ° C. or lower, more preferably 4 ° C. or higher and 12 ° C. or lower. To do.
By such a method, the uneven distribution of additives (plasticizer, ultrafine particles, UV absorber, etc.) added in the film during the stretching process is eliminated, and the optical properties of the obtained film are homogenized. And mechanical properties are improved.

  Further, the dope may be cast simultaneously with other functional layers (for example, an adhesive layer, a dye layer, an antistatic layer, an antihalation layer, a UV absorption layer, a polarizing layer).

As described above, in the present invention, the support is a cellulose acylate film, and the cellulose acylate film is obtained by converting cellulose acylate into a substantially non-chlorine solvent. A film prepared by a solution preparing step for preparing a cellulose acylate solution, a film forming step for forming a cellulose acylate film from the cellulose acylate solution, and a stretching step for stretching the cellulose acylate film is preferable. .
In order to make the film thickness variation width of the cellulose acylate film within ± 3%, (1) adjust the concentration and viscosity when casting a solution (dope) in which the cellulose acylate film is dissolved in an organic solvent, (2) It is effective to adjust the drying temperature of the film surface in the drying step, the air volume when using the drying air, the wind direction, and the like.

[Characteristics of cellulose acylate film (surface shape)]
In the optical film of the present invention, the cellulose acylate film used as a support preferably has a specific surface shape. Hereinafter, the surface shape of the cellulose acylate film will be described.
The surface of the cellulose acylate film on which the antireflection layer is provided has an arithmetic average roughness (Ra) of the surface irregularity of the film based on JIS B0601-1994 of 0.0005 to 0.1 μm, a ten-point average roughness (Rz). ) Is 0.001 to 0.3 μm, and the maximum height (Ry) is 0.5 μm or less, preferably (Ra) is 0.0002 to 0.05 μm, (Rz) is 0.005 to 0.1 μm, (Ry) is 0.3 μm or less, particularly preferably (Ra) is 0.001 to 0.02 μm, (Rz) is 0.002 to 0.05 μm, and (Ry) is 0.1 μm or less.
The above range is preferable for providing an optical functional layer having a uniform coated surface with no coating unevenness and good adhesion between the support and the coated film.

Furthermore, in the fine surface irregularity form, the ratio (Ra / Rz) of arithmetic average roughness (Ra) to ten-point average roughness (Rz) is preferably 0.1 or more, and JIS B0601-1994. It is preferable that the average space | interval (Sm) of the film surface unevenness | corrugation based on is 2 micrometers or less. Here, the relationship between Ra and Rz indicates the uniformity of surface irregularities. More preferably, the (Ra / Rz) ratio is 0.15 or more and the average interval (Sm) is 1 to 0.1, and particularly preferably the (Ra / Rz) ratio is 0.2 or more and the average interval (Sm) is 0.1 to 0.001 μm.
The concave and convex shapes on the surface can be evaluated with a transmission electron microscope (TEM), an atomic force microscope (AFM), or the like.
The number of optical defects having a visual size of 100 μm or more in the cellulose acylate film is preferably 1 or less per 1 m ² from the viewpoint of reducing visual defects and improving the yield.
This optical defect can be observed using a polarizing microscope with the slow axis of the film parallel to the absorption axis of the polarizer under crossed Nicols. The defects that appear as bright spots are approximated in a circular area, and those having a diameter of 100 μm or more are counted. Bright spots of 100 μm or more can be easily observed with the naked eye.
That is, the surface of the cellulose acylate film has an arithmetic average roughness (Ra) of surface irregularities based on JIS B0601-1994 of 0.0005 to 0.1 μm, and a ten-point average roughness (Rz) of 0.001. The number of optical defects having an average distance (Sm) of up to 0.3 μm and surface irregularities of 2 μm or less and a visual size of 100 μm or more is ² per 1 m 2.
The number is preferably 1 or less, particularly 1 or less.

[Optical properties of film]
The cellulose acylate film preferably has a light transmittance of 90% or more and a haze of 1% or less. More preferably, the light transmittance is 92% or more and the haze is 0 to 0.5%.
The haze value can be measured using a haze meter (for example, MODEL 1001DP manufactured by Nippon Denshoku Industries Co., Ltd., HR-100 manufactured by Murakami Color Research Laboratory, etc.) according to JIS-K-7105.

[Mechanical properties of film]
(Tear strength)
The cellulose acylate film has a tear strength of 2 g or more based on the tear test method (Elmendorf tear method) of JIS K7128-2: 1998. This is preferable. More preferably, it is 5-25g, More preferably, it is 6-25g. Further, in terms of 60 μm, 8 g or more is preferable, and more preferably 8 to 15 g.
Specifically, it can be measured using a light load tear strength tester after conditioning a sample piece of 50 mm × 64 mm under the conditions of 25 ° C. and 65% RH for 2 hours.

(Scratch strength)
The scratch strength is preferably 2 g or more, more preferably 5 g or more, and particularly preferably 10 g or more. By setting it as this range, the scratch resistance and handling property of the film surface can be maintained without any problem.
The scratch strength can be evaluated with a load (g) that allows the surface of the support to be scratched using a sapphire needle having a cone apex angle of 90 degrees and a tip radius of 0.25 m, and the scratch mark can be visually confirmed.

[Residual solvent amount of film]
Curling can be suppressed by setting the residual solvent amount of the support used in the present invention to 0 to 1.5%. The residual solvent amount is more preferably 0 to 1.0%.
This is presumably because the main effect factor is that the free volume is reduced by reducing the amount of residual solvent during film formation by the solvent casting method described above.
Specifically, it is preferable to dry under the condition that the residual solvent amount with respect to the cellulose acylate film is in the range of 0.01 to 1.5% by mass. More preferably, it is 0.01-1.0 mass%.

[Water permeability and moisture content of film]
The moisture permeability of the cellulose acylate film used in the present invention is preferably within the aforementioned range in the method described in JIS standard JIS Z0208 (temperature 25 ° C., humidity 90% RH). Thereby, the adhesion failure of the antireflection layer is reduced, and when incorporated in a liquid crystal display device as a protective film for an optical compensation film or a polarizing plate, a change in color and a decrease in viewing angle are not caused.
The moisture permeability measurement method is described in “Polymer Physical Properties II” (Polymer Experiment Course 4 Kyoritsu Shuppan) p. 285-294: The method described in the measurement of vapor permeation amount (mass method, thermometer method, vapor pressure method, adsorption amount method) can also be applied.

The water content of the cellulose acylate film is 0.3-12 g / m ² at 30 ° C. and 85% RH regardless of the film thickness so as not to impair the adhesiveness with water-soluble polymers such as polyvinyl alcohol. Preferably there is. And more preferably 0.5 to 5 g / ^{m 2.}
If it is larger than 12 g / m ^{2, the} dependency of retardation due to a change in humidity increases, which is not preferable.

  Moreover, at least one surface of the cellulose acylate film of the present invention may be surface-treated. Examples of the surface treatment include vacuum glow discharge treatment, atmospheric pressure plasma discharge treatment, ultraviolet irradiation treatment, corona treatment, flame treatment, acid treatment or alkali treatment.

<Coating solution>
Next, in the present invention, the coating liquid applied on the cellulose acylate film is shown.
In the present invention, a coating solution containing an organic solvent is applied directly on the cellulose acylate film. The coating solution containing an organic solvent generally contains components that form layers having characteristics such as an optical functional layer and a physical functional layer. Here, coating directly on the support means coating in a state where no layer is provided between the coating liquid and the support surface, and various surface treatments are applied to the surface of the cellulose acylate film. May be. However, it is preferable to apply the organic solvent directly on the cellulose acylate film that has not been surface-treated.

In the coating liquid for forming the optical functional layer and the physical functional layer, the type of solvent is selected from the viewpoints of the solubility and stability of the components contained in the coating liquid and the dispersion stability of the particle components. From such points, ketones, esters, hydrocarbons, and halogenated hydrocarbons are suitable. For organic solvents used for coating, consideration should be given to the safety of the human body and ecosystem, explosion-proof safety, greenhouse effect due to environmental release, ozone depletion, etc. It is necessary. From such a viewpoint, solvents of ketones and esters are suitable and are most commonly used.
However, the ketone and ester solvents are soluble and permeable to the cellulose acylate film of the present invention, and partially dissolve or swell the transparent support. For this reason, when coating is performed, coating unevenness and drying unevenness may occur due to changes in coating properties due to solubility and permeability, changes in drying properties, changes in permeability due to drying conditions, and the like.
In order to adjust the solubility and the permeability, a method of applying an insoluble solvent in addition to a solvent for dissolving cellulose acylate is disclosed in Japanese Patent Application Laid-Open No. 2002-169001. This suppresses changes in optical properties due to penetration of components in the coating solution and improves adhesion by penetration.
On the other hand, in the application of organic solvent to cellulose acylate film, we examined the improvement of the coating surface condition, and the plasticizer content on the surface in cellulose acylate greatly affects the coating solution of the present invention. I found. It has been found that this can be adjusted based on the permeability of the solvent type used to the cellulose acylate film as the base material.

Specific examples of ketones and esters used in the present invention include low-boiling solvents having a boiling point of 100 ° C. or lower, acetone (56.1 ° C .: hereinafter omitted), 2-butanone (= methyl ethyl ketone). : Ketones such as MEK, 79.6), and esters such as ethyl formate (54.2), methyl acetate (57.8), ethyl acetate (77.1), isopropyl acetate (89), and the like.
Examples of the high boiling point solvent having a boiling point of 100 ° C. or higher include butyl acetate (126), isobutyl acetate (118), cyclohexanone (155.7), 2-methyl-4-pentanone (= methyl isobutyl ketone: MIBK). 115.9), 2-octanone (173), diacetone alcohol (168), and the like. Of these, acetone, methyl ethyl ketone, methyl acetate, ethyl acetate, cyclohexanone, methyl isobutyl ketone and the like are preferable. However, the organic solvent of the present invention is not limited to the above.

  It is also preferable to mix a solvent having almost no permeability to the cellulose acylate film with the above ketone-based and ester-based solvents. As such a solvent, the above-mentioned ketones and esters which are hardly permeable can be selected. In addition, alcohols, amides, ethers, ether esters, aliphatic hydrocarbons, aromatics Various solvents such as group hydrocarbons and halogenated hydrocarbons can be used. Moreover, it can also be used by mixing with solvents other than organic solvents, such as water and a fluorine-type solvent. The selection of these solvents is appropriately selected from the viewpoints of solubility of components contained in the coating solution, reactivity, stability of added particles, drying properties in the drying process, viscosity adjustment, etc., and mixing The ratio can be selected.

  Specific examples of the above solvents include, in addition to the ketones and esters described above, low boiling solvents having a boiling point of 100 ° C. or lower, such as hexane (boiling point 68.7), heptane (98.4), cyclohexane. (80.7), hydrocarbons such as benzene (80.1), dichloromethane (39.8), chloroform (61.2), carbon tetrachloride (76.8), 1,2-dichloroethane (83.5) ), Halogenated hydrocarbons such as trichlorethylene (87.2), ethers such as diethyl ether (34.6), diisopropyl ether (68.5), dipropyl ether (90.5), tetrahydrofuran (66), Methanol (64.5), ethanol (78.3), 2-propanol (82.4), 1-propanol (97.2), 2-butanol (99 5), alcohols such as t- butanol (82.5), acetonitrile (81.6), cyano compounds such as propionitrile (97.4), carbon disulfide (46.2), and the like.

  Examples of the solvent having a boiling point of 100 ° C. or higher include, for example, octane (125.7), toluene (110.6), xylene (138), tetrachloroethylene (121.2), chlorobenzene (131.7), dioxane (101 .3), dibutyl ether (142.4), 1-butanol (117.7), iso-butanol (107.9), propylene glycol monomethyl ether (120), N, N-dimethylformamide (153), N, N-dimethylacetamide (166), dimethyl sulfoxide (189), and the like. However, the organic solvent of the present invention is not limited to the above.

  In addition, about the above solvent, it is preferable to select a solvent seed | species and a solvent composition suitably on the basis of the permeability | transmittance of the solvent to a cellulose acylate film. The penetrability of various solvents can be determined by curling properties when coating solutions containing various solvents are applied, and the penetrating depth of the applied components. As a method for checking the permeability of a dye, a dye or the like is mixed in a solvent, and a cellulose acylate film as a base material is immersed in the solvent for a certain period of time. There is a way to see the depth of soaking. For example, when a commercially available cellulose triacetate film TD-80U is immersed in a solvent containing a dye for 2 seconds and dried at 45 ° C. for 5 minutes, the solvent penetration degree is as follows: MIBK 0%, MEK 50%, cyclohexanone 10% , Acetone 100%, ethyl acetate 1%, toluene 0%, methanol 1%, and the like. The solvent that permeates the cellulose acylate film is a solvent having a permeability of about 2% or more by the above method, and a solvent that is less than 2% can be regarded as a solvent that does not penetrate. As one example, specific examples of solvents that are permeable to the cellulose triacetate film include ketones such as acetone, MEK, cyclohexanone, diacetone alcohol, and esters such as methyl acetate. Non-permeable solvents include ketones such as MIBK, 2-octanone, esters as ethyl acetate, other hydrocarbon hexanes, cyclohexane, benzene, toluene, xylene, etc., alcohols as methanol, ethanol, propanol, butanol Etc. However, these penetrating / non-penetrating solvents vary depending on the composition of the cellulose acylate of the base material, the type of plasticizer, and the like.

Further, among the above solvents, it is preferable to mix a non-permeable solvent in addition to the ketone and ester solvents of the present invention. Further, the ketone and ester of the present invention are more preferably permeable solvents. Furthermore, it is particularly preferable that the permeable and non-permeable solvents are ketones and esters. In view of the above, particularly preferred are MEK / MIBK mixed solvents, MIBK / cyclohexanone mixed solvents, and the like. These mixing ratios can be appropriately adjusted from the viewpoints of drying properties, solubility of coating solution components, permeability to the substrate, and the like.
In addition, in order to adjust the drying property, viscosity, surface tension and the like of the solvent, several kinds of solvents having different characteristics can be mixed and used. In particular, mixing of a solvent having a high boiling point is preferable for providing solubility of the components therein, providing dispersion stability, suppressing deterioration of drying unevenness due to rapid drying of the coating liquid, and suppressing increase in moisture content of the coating liquid.

<Functional layer application>
Next, the coating layer provided by coating of a coating solution containing an organic solvent in the optical film of the present invention will be described. The coating layer in the present invention has properties such as an optical functional layer and a physical functional layer. Examples of the optical functional layer include an antiglare layer, a light diffusion layer, a low refractive index layer, a high refractive index layer, an optical compensation layer, and the like. Examples of the physical functional layer include a hard coat layer. Of course, the optical functional layer may also serve as a physical functional layer, for example, an antiglare hard coat layer.
In the present invention, an antiglare (hard coat) layer, a light diffusion layer, a hard coat layer and the like are preferably applied directly onto the cellulose acylate.

As one embodiment of the present invention, a basic configuration of an antireflection film, which is a preferred embodiment of the optical functional film of the present invention, will be described with reference to the drawings.
The cross-sectional view schematically shown in FIG. 1 (a) is an example of the antireflection film of the present invention. The antireflection film 1 includes a transparent support 2, three types of functional layers (a hard coat layer 3, an antiglare layer). Layer structure of the functional hard coat layer 4 and the low refractive index layer 5). Matte particles 6 are dispersed in the antiglare hard coat layer 4 and the refractive index of the material other than the matte particles 6 of the antiglare hard coat layer 4 is in the range of 1.50 to 2.00. The refractive index of the low refractive index layer 5 is preferably in the range of 1.35 to 1.49. In the present invention, the functional layer may be a hard coat layer having an antiglare property as described above, a hard coat layer not having an antiglare property, a light diffusion layer, a single layer, a plurality of layers, For example, it may be composed of 2 to 4 layers. The low refractive index layer which is a functional layer is coated on the outermost layer.
Further, the low refractive index layer preferably satisfies the following formula (VI) from the viewpoint of reducing the reflectance.
Formula (VI): (m / 4) × 0.7 <n ₁ d ₁ <(m / 4) × 1.3
In the formula, m is a positive odd number, n ₁ is the refractive index of the low refractive index layer, and d ₁ is the film thickness (nm) of the low refractive index layer. Further, λ is a wavelength, which is a value in the range of 500 to 550 nm.
In addition, satisfy | filling said numerical formula (VI) means that m (positive odd number, usually 1) which satisfy | fills numerical formula (VI) exists in the said wavelength range.

The cross-sectional view schematically shown in FIG. 1 (b) is an example of the antireflection film of the present invention. The antireflection film 1 includes a transparent support 2, each functional layer (hard coat layer 3, medium refractive index). Layer 7, high refractive index layer 8), and low refractive index layer (outermost layer) 5. The transparent support 2, the medium refractive index layer 7, the high refractive index layer 8, and the low refractive index layer 5 have refractive indexes that satisfy the following relationship.
Refractive index of high refractive index layer> refractive index of medium refractive index layer> refractive index of transparent support> refractive index of low refractive index layer In the layer structure as shown in FIG. As described above, the medium refractive index layer satisfies the following formula (VII), the high refractive index layer satisfies the following formula (VIII), and the low refractive index layer satisfies the following formula (IX). It is preferable at the point which can produce the antireflection film which has prevention performance.

Formula (VII): (hλ / 4) × 0.7 <n ₁ d ₁ <(hλ / 4) × 1.3
In formula (VII), h is a positive integer (generally 1, 2 or 3), n ₁ is the refractive index of the medium refractive index layer, and d ₁ is the layer thickness (nm) of the medium refractive index layer. It is. λ is the wavelength (nm) of visible light, and is a value in the range of 380 to 680 nm.
Formula (VIII): (iλ / 4) × 0.7 <n ₂ d ₂ <(iλ / 4) × 1.3
In formula (VIII), i is a positive integer (generally 1, 2 or 3), n ₂ is the refractive index of the high refractive index layer, and d ₂ is the layer thickness (nm) of the high refractive index layer. is there. λ is the wavelength (nm) of visible light, and is a value in the range of 380 to 680 nm.

Formula (IX): (jλ / 4) × 0.7 <n ₃ d ₃ <(jλ / 4) × 1.3
In formula (IX), j is a positive odd number (generally 1), n ₃ is the refractive index of the low refractive index layer, and d ₃ is the layer thickness (nm) of the low refractive index layer. λ is the wavelength (nm) of visible light, and is a value in the range of 380 to 680 nm.

In the layer configuration as shown in FIG. 1B, the medium refractive index layer satisfies the following formula (X), the high refractive index layer satisfies the following formula (XI), and the low refractive index layer satisfies the following formula (XII). Particularly preferred. Here, λ is 500 nm, h is 1, i is 2, and j is 1.
Formula (X):
(Hλ / 4) × 0.80 <n ₁ d ₁ <(hλ / 4) × 1.00
Formula (XI):
(Iλ / 4) × 0.75 <n ₂ d ₂ <(iλ / 4) × 0.95
Formula (XII):
(Jλ / 4) × 0.95 <n ₃ d ₃ <(jλ / 4) × 1.05

  The high refractive index, medium refractive index, and low refractive index described here refer to the relative refractive index between layers. Moreover, in FIG.1 (b), the high refractive index layer is used as a light interference layer, and the antireflection film which has the very outstanding antireflection performance can be produced.

Next, each functional layer of the optical film of the present invention will be described.
[Anti-glare hard coat layer]
The antiglare hard coat layer of the present invention will be described below.
The antiglare hard coat layer is a binder for imparting hard coat properties as main components, matte particles for imparting antiglare properties, and an inorganic material for increasing the refractive index, preventing crosslinking shrinkage, and increasing the strength. It is formed from a filler or the like.
The binder is preferably a polymer having a saturated hydrocarbon chain or a polyether chain as the main chain, and more preferably a polymer having a saturated hydrocarbon chain as the main chain. The binder polymer preferably has a crosslinked structure.
As the binder polymer having a saturated hydrocarbon chain as a main chain, a polymer of an ethylenically unsaturated monomer (binder precursor) is preferable. As the binder polymer having a saturated hydrocarbon chain as the main chain and having a crosslinked structure, a (co) polymer of monomers having two or more ethylenically unsaturated groups is preferable.
In order to obtain a high refractive index, the monomer structure preferably contains an aromatic ring or at least one atom selected from halogen atoms other than fluorine, sulfur atoms, phosphorus atoms, and nitrogen atoms.

  Examples of the binder include polyfunctional monomers and polyfunctional oligomers having radically polymerizable or cationically polymerizable groups.

Examples of the radical polymerizable functional group include an ethylenically unsaturated group such as a (meth) acryloyl group, a vinyloxy group, a styryl group, and an allyl group. Among them, a (meth) acryloyl group is preferable. It is preferable to contain a polyfunctional monomer containing two or more radically polymerizable groups in the molecule.

  The radical polymerizable polyfunctional monomer is preferably selected from compounds having at least two terminal ethylenically unsaturated bonds. Preferably, it is a compound having 2 to 6 terminal ethylenically unsaturated bonds in the molecule. Such a compound group is widely known in the polymer material field, and these can be used without particular limitation in the present invention. These can have chemical forms such as, for example, monomers, prepolymers (ie, dimers, trimers and oligomers) or mixtures thereof, and copolymers thereof.

  These binder components are preferably resins having an acrylate functional group, such as relatively low molecular weight polyester resins, polyether resins, acrylic resins, epoxy resins, urethane resins, alkyd resins, spiroacetal resins, polybutadiene resins. , Oligomers or prepolymers such as (meth) acrylates of polyfunctional compounds such as polythiol polyene resins and polyhydric alcohols (hereinafter, acrylate and methacrylate are referred to as (meth) acrylates). . Specific examples of the polyfunctional monomer include, for example, trimethylolpropane tri (meth) acrylate, EO-modified trimethylolpropane tri (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, hexanediol (meth) acrylate, and tripropylene glycol. Di (meth) acrylate, diethylene glycol di (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, dipentaerythritol hexa (meth) acrylate and penta (Meth) acrylate mixtures, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, etc.It is also preferable to mix a monofunctional monomer such as ethyl (meth) acrylate, ethylhexyl (meth) acrylate, styrene, vinyltoluene, or N-vinylpyrrolidone.

  In addition, for example, as a polymerizable ester compound (monoester or polyester) of an aliphatic polyhydric alcohol compound and an unsaturated carboxylic acid, paragraph numbers [0026] to [0027] of JP-A-2001-139663 are disclosed. And the compounds described. Further, for example, vinyl methacrylate, allyl methacrylate, allyl acrylate, aliphatic alcohol esters described in JP-B-46-27926, JP-B-51-47334, JP-A-57-196231, and JP-A-2 Those having an aromatic skeleton described in JP-A No. 226149 and those having an amino group described in JP-A No. 1-165613 are also preferably used. In addition, a vinylurethane compound containing two or more polymerizable vinyl groups in one molecule (Japanese Patent Publication No. 48-41708), urethane acrylates (Japanese Patent Publication No. 2-16765), an ethylene oxide skeleton Urethane compounds (Japanese Examined Patent Publication No. 62-39418), polyester acrylates (Japanese Examined Patent Publication No. 52-30490, etc.), and further described in Journal of Japan Adhesion Association Vol. 20 (7), 300-308 (1984) These photocurable monomers and oligomers can also be used.

  As these binders, commercially available products such as Nippon Kayaku Co., Ltd., Osaka Organic Chemical Co., Ltd., Dainippon Ink Chemical, Toa Gosei, Mitsubishi Chemical, etc. can be used.

Two or more of these actinic radiation curable resins may be used in combination. Of these, particularly preferred are pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, dipentaerythritol hexa (meth) acrylate and penta (meth) acrylate. A mixture of trimethylolpropane tri (meth) acrylate, EO-modified trimethylolpropane tri (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, and the like.

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

Polymerization of the monomer having an ethylenically unsaturated group can be performed by irradiation with ionizing radiation or heating in the presence of a photo radical initiator or a thermal radical initiator.
Accordingly, a coating liquid containing a monomer having an ethylenically unsaturated group, a photo radical initiator or a thermal radical initiator, mat particles, and an inorganic filler is prepared, and the coating liquid is applied on a transparent support and then ionizing radiation or heat is applied. It can be cured by a polymerization reaction to form an antireflection film.

As radical photopolymerization initiators, acetophenones, benzoins, benzophenones, phosphine oxides, ketals, anthraquinones, thioxanthones, azo compounds, peroxides, 2,3-alkyldione compounds, disulfide compounds And fluoroamine compounds and aromatic sulfoniums. Examples of acetophenones include 2,2-ethoxyacetophenone, p-methylacetophenone, 1-hydroxydimethylphenyl ketone, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-4-methylthio-2-morpholinopropiophenone and 2- Benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone is included. Examples of benzoins include benzoin benzene sulfonate, benzoin toluene sulfonate, benzoin methyl ether, benzoin ethyl ether and benzoin isopropyl ether. Examples of benzophenones include benzophenone, 2,4-chlorobenzophenone, 4,4-dichlorobenzophenone and p-chlorobenzophenone. Examples of phosphine oxides include 2,4,6-trimethylbenzoyldiphenylphosphine oxide.
Various examples are described in the latest UV curing technology (P.159, issuer; Kazuhiro Takashiro, publisher; Technical Information Association, Inc., published in 1991), which is useful for the present invention.
Preferable examples of commercially available photocleavable photoradical polymerization initiators include Irgacure (651, 184, 907) manufactured by Nippon Ciba-Geigy Co., Ltd.
Further, as described in JP-A-6-41468, it is also preferably used in combination of two photopolymerization initiators.
It is preferable to use a photoinitiator in the range of 0.1-15 mass parts with respect to 100 mass parts of polyfunctional monomers, More preferably, it is the range of 1-10 mass parts.
In addition to the photopolymerization initiator, a photosensitizer may be used. Specific examples of the photosensitizer include n-butylamine, triethylamine, tri-n-butylphosphine, Michler's ketone and thioxanthone.

As the thermal radical initiator, organic or inorganic peroxides, organic azo, diazo compounds, and the like can be used.
Specifically, benzoyl peroxide, halogen benzoyl peroxide, lauroyl peroxide, acetyl peroxide, dibutyl peroxide, cumene hydroperoxide, butyl hydroperoxide as organic peroxides, hydrogen peroxide, peroxides as inorganic peroxides. Ammonium sulfate, potassium persulfate, etc., 2-azo-bis-isobutyronitrile, 2-azo-bis-propionitrile, 2-azo-bis-cyclohexanedinitrile, etc. as diazo compounds, diazoaminobenzene, p-nitrobenzenediazonium Etc.

The polymer having a polyether as the main chain is preferably a ring-opening polymer of a polyfunctional epoxy compound. The ring-opening polymerization of the polyfunctional epoxy compound can be performed by irradiation with ionizing radiation or heating in the presence of a photoacid generator or a thermal acid generator.
Therefore, a coating liquid containing a polyfunctional epoxy compound, a photoacid generator or a thermal acid generator, matte particles and an inorganic filler is prepared, and the coating liquid is applied on a transparent support and then subjected to a polymerization reaction by ionizing radiation or heat. It can be cured to form an antireflective film.

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

  The binder of the antiglare hard coat layer is added in an amount of 20 to 95% by mass based on the solid content of the coating composition of the layer.

For the purpose of imparting antiglare properties, the antiglare hard coat layer is a matte particle having an average particle size of 1 to 10 μm, preferably 1.5 to 7.0 μm, such as inorganic compound particles or resin, for the purpose of imparting antiglare properties. Contains particles.
As specific examples of the mat particles, particles of inorganic compounds such as silica particles and TiO ₂ particles; resin particles such as acrylic particles, crosslinked acrylic particles, polystyrene particles, crosslinked styrene particles, melamine resin particles, and benzoguanamine resin particles are preferable. Can be mentioned. Of these, crosslinked styrene particles, crosslinked acrylic particles, and silica particles are preferred.
As the shape of the mat particle, either a true sphere or an indefinite shape can be used.

  Two or more kinds of mat particles having different particle diameters may be used in combination. It is possible to impart anti-glare properties with mat particles having a larger particle size and to impart other optical characteristics with mat particles having a smaller particle size. For example, when an antireflection film is attached to a high-definition display of 133 ppi or higher, it is required that there is no problem in optical performance called glare. Glare originates from the fact that the pixels are enlarged or reduced due to unevenness existing on the film surface (contributing to anti-glare properties) and lose uniformity of brightness, but with a particle size smaller than that of mat particles that provide anti-glare properties. It can be greatly improved by using mat particles having a different refractive index from the binder.

Furthermore, the particle size distribution of the mat particles is most preferably monodisperse, and the particle sizes of the particles are preferably closer to each other. For example, when a particle having a particle size of 20% or more than the average particle size is defined as a coarse particle, the proportion of the coarse particle is preferably 1% or less, more preferably 0.1% of the total number of particles. Or less, more preferably 0.01% or less. Matt particles having such a particle size distribution are obtained by classification after a normal synthesis reaction, and a matting agent having a more preferable distribution can be obtained by increasing the number of classifications or increasing the degree of classification.

The mat particles are contained in the antiglare hard coat layer so that the amount of mat particles in the formed antiglare hard coat layer is preferably 10 to 2000 mg / m ² , more preferably 100 to 1400 mg / m ^2. Is done.
The particle size distribution of the matte particles is measured by a Coulter counter method, and the measured distribution is converted into a particle number distribution.

In order to increase the refractive index of the antiglare hard coat layer, in addition to the above mat particles, at least one metal selected from titanium, zirconium, aluminum, indium, zinc, tin and antimony is used. It is preferable to contain an inorganic filler made of an oxide and having an average particle size of 0.2 μm or less, preferably 0.1 μm or less, more preferably 0.06 μm or less.
Conversely, in order to increase the difference in refractive index from the matte particles, an anti-glare hard coat layer using high-refractive index matte particles uses silicon oxide to keep the refractive index of the layer low. Is also preferable. The preferred particle size is the same as that of the aforementioned inorganic filler.
Specific examples of the inorganic filler used in the antiglare hard coat layer include TiO ₂ , ZrO ₂ , Al ₂ O ₃ , In ₂ O ₃ , ZnO, SnO ₂ , Sb ₂ O ₃ , ITO and SiO _2. It is done. TiO ₂ and ZrO ₂ are particularly preferable from the viewpoint of increasing the refractive index. The surface of the inorganic filler is preferably subjected to a silane coupling treatment or a titanium coupling treatment, and a surface treatment agent having a functional group capable of reacting with a binder species on the filler surface is preferably used.
The amount of these inorganic fillers added is preferably 10 to 90% of the total mass of the antiglare hard coat layer, more preferably 20 to 80%, and particularly preferably 30 to 75%.
Such a filler does not scatter because the particle size is sufficiently smaller than the wavelength of light, and a dispersion in which the filler is dispersed in a binder polymer behaves as an optically uniform substance.

  The bulk refractive index of the mixture of binder and inorganic filler in the antiglare hard coat layer of the present invention is preferably 1.48 to 2.00, more preferably 1.50 to 1.80. In order to make the refractive index within the above range, the kind and amount ratio of the binder and the inorganic filler may be appropriately selected. How to select can be easily known experimentally in advance.

  The film thickness of the antiglare hard coat layer is preferably 1 to 10 μm, and more preferably 1.2 to 8 μm.

(Organosilane sol)
At least one of the functional layers constituting the antireflection film of the present invention includes at least one component of an organosilane compound, a hydrolyzate thereof and a partial condensate thereof, a so-called sol, in the coating liquid forming the layer. It is preferable in terms of scratch resistance to contain a component (hereinafter sometimes referred to as such). This sol component is condensed by a drying and heating process after coating the coating solution to form a cured product, which becomes a binder for the layer. Moreover, when this hardened | cured material has a polymerizable unsaturated bond, the binder which has a three-dimensional structure is formed by irradiation of actinic light.
The organosilane compound is preferably one represented by the following general formula 4.
General formula 4: (R < ¹⁰ >) _m- Si (X) _4-m
In the above general formula 4, R ¹⁰ represents a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group. As an alkyl group, a C1-C30 alkyl group is preferable, More preferably, it is C1-C16, Most preferably, it is a C1-C6 thing. Specific examples of the alkyl group include methyl, ethyl, propyl, isopropyl, hexyl, decyl, hexadecyl and the like. Examples of the aryl group include phenyl and naphthyl, and a phenyl group is preferable.
X represents a hydroxyl group or a hydrolyzable group, for example, an alkoxy group (preferably an alkoxy group having 1 to 5 carbon atoms, such as a methoxy group or an ethoxy group), a halogen atom (for example, Cl, Br, I or the like). ) And R ² COO (R ² is preferably a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, such as CH ₃ COO, C ₂ H ₅ COO, etc.), preferably An alkoxy group, particularly preferably a methoxy group or an ethoxy group.
m represents an integer of 1 to 3, preferably 1 or 2, and particularly preferably 1.

In general formula 4, when R ¹⁰ or X there are a plurality, a plurality of R ¹⁰ or X groups may be different, even the same, respectively.
The substituent contained in R ¹⁰ is not particularly limited, but a halogen atom (fluorine, chlorine, bromine, etc.), a hydroxyl group, a mercapto group, a carboxyl group, an epoxy group, an alkyl group (methyl, ethyl, i-propyl, propyl, t-butyl etc.), aryl groups (phenyl, naphthyl etc.), aromatic heterocyclic groups (furyl, pyrazolyl, pyridyl etc.), alkoxy groups (methoxy, ethoxy, i-propoxy, hexyloxy etc.), aryloxy (phenoxy etc.) ), Alkylthio groups (methylthio, ethylthio, etc.), arylthio groups (phenylthio, etc.), alkenyl groups (vinyl, 1-propenyl, etc.), acyloxy groups (acetoxy, acryloyloxy, methacryloyloxy, etc.), alkoxycarbonyl groups (methoxycarbonyl, ethoxy) Carbonyl), arylo Xyloxycarbonyl groups (phenoxycarbonyl, etc.), carbamoyl groups (carbamoyl, N-methylcarbamoyl, N, N-dimethylcarbamoyl, N-methyl-N-octylcarbamoyl, etc.), acylamino groups (acetylamino, benzoylamino, acrylicamino, methacrylic) Amino) and the like, and these substituents may be further substituted.

In the general formula 4, when there are a plurality of R ¹⁰ , at least one of them is preferably a substituted alkyl group or a substituted aryl group. Among them, an organosilane compound having a vinyl polymerizable substituent represented by the following general formula 1 Is preferred.
General formula 1

In the above general formula 1, R ¹ represents a hydrogen atom, a methyl group, a methoxy group, an alkoxycarbonyl group, a cyano group, a fluorine atom, or a chlorine atom. Examples of the alkoxycarbonyl group include a methoxycarbonyl group and an ethoxycarbonyl group. A hydrogen atom, a methyl group, a methoxy group, a methoxycarbonyl group, a cyano group, a fluorine atom and a chlorine atom are preferred, a hydrogen atom, a methyl group, a methoxycarbonyl group, a fluorine atom and a chlorine atom are more preferred, and a hydrogen atom and a methyl group Is particularly preferred.
Y represents a single bond or * -COO-**, * -CONH-** or * -O-**, preferably a single bond, * -COO-** or * -CONH-**, * -COO-** is more preferable, and * -COO-** is particularly preferable. * Represents a position bonded to ═C (R ¹ ) —, and ** represents a position bonded to L.

  In General Formula 1, L represents a divalent linking chain. Specifically, a substituted or unsubstituted alkylene group, a substituted or unsubstituted arylene group, a substituted or unsubstituted alkylene group having a linking group (for example, ether, ester, amide, etc.) inside, and a linking group inside. A substituted or unsubstituted arylene group, a substituted or unsubstituted alkylene group, a substituted or unsubstituted arylene group, an alkylene group having a linking group therein is preferred, an unsubstituted alkylene group, an unsubstituted arylene group Further, an alkylene group having an ether or ester linking group inside is more preferable, an unsubstituted alkylene group, and an alkylene group having an ether or ester linking group inside is particularly preferable. Examples of the substituent include a halogen, a hydroxyl group, a mercapto group, a carboxyl group, an epoxy group, an alkyl group, and an aryl group, and these substituents may be further substituted.

In General Formula 1, l represents a number satisfying the mathematical formula of l = 100−m, and m represents a number from 0 to 50. As for m, the number of 0-40 is more preferable, and the number of 0-30 is especially preferable.
R ^{2 to} R ⁴ are preferably a halogen atom, a hydroxyl group, an unsubstituted alkoxy group, or an unsubstituted alkyl group. R ^{2 to} R ⁴ are more preferably a chlorine atom, a hydroxyl group, or an unsubstituted alkoxy group having 1 to 6 carbon atoms, more preferably a hydroxyl group or an alkoxy group having 1 to 3 carbon atoms, and particularly preferably a hydroxyl group or a methoxy group.
R ⁵ represents a hydrogen atom or an unsubstituted alkyl group. R ⁵ is preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, particularly preferably a hydrogen atom or a methyl group.

In general formula 1, R ⁶ represents a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group. As an alkyl group, a C1-C30 alkyl group is preferable, More preferably, it is C1-C16, Most preferably, it is a C1-C6 thing. Specific examples of the alkyl group include methyl, ethyl, propyl, isopropyl, hexyl, decyl, hexadecyl and the like. Examples of the aryl group include phenyl and naphthyl, and a phenyl group is preferable. The substituent contained in R ⁶ is not particularly limited, but a halogen atom (fluorine, chlorine, bromine, etc.), a hydroxyl group, a mercapto group, a carboxyl group, an epoxy group, an alkyl group (methyl, ethyl, i-propyl, propyl, t-butyl etc.), aryl groups (phenyl, naphthyl etc.), aromatic heterocyclic groups (furyl, pyrazolyl, pyridyl etc.), alkoxy groups (methoxy, ethoxy, i-propoxy, hexyloxy etc.), aryloxy (phenoxy etc.) ), Alkylthio groups (methylthio, ethylthio, etc.), arylthio groups (phenylthio, etc.), alkenyl groups (vinyl, 1-propenyl, etc.), acyloxy groups (acetoxy, acryloyloxy, methacryloyloxy, etc.), alkoxycarbonyl groups (methoxycarbonyl, ethoxy) Carbonyl, etc.), aryloxy Sicarbonyl group (phenoxycarbonyl etc.), carbamoyl group (carbamoyl, N-methylcarbamoyl, N, N-dimethylcarbamoyl, N-methyl-N-octylcarbamoyl etc.), acylamino group (acetylamino, benzoylamino, acrylamino, methacryl) Amino) and the like, and these substituents may be further substituted. A polymerizable functional group other than the vinyl polymerizable group such as an epoxy group or an isocyanate group is also preferable as a substituent. The substituent for R ⁶ is more preferably a hydroxyl group or an unsubstituted alkyl group, more preferably a hydroxyl group or an alkyl group having 1 to 3 carbon atoms, and particularly preferably a hydroxyl group or a methyl group.

  Two or more compounds of the general formula 1 may be used in combination. In particular, the compound of the general formula 1 can be synthesized using a plurality of silane compounds as starting materials. Although the specific example of the starting material of the compound of General formula 4 and the compound represented by General formula 1 is shown below, it is not limited.

_{M-48: CH 3 -Si (} OCH 3) 3
_{M-49: C 2 H 5} -Si (OCH 3) 3
_{M-50: t-C 4} H 9 -Si (OCH 3) 3

Of these, (M-1), (M-2), and (M-25) are particularly preferable as the organosilane containing a polymerizable group.
In order to obtain the effect of the present invention, the content of the organosilane containing the vinyl polymerizable group in the hydrolyzate of organosilane and / or its partial condensate is preferably 30% by mass to 100% by mass, The mass% is more preferably 100% by mass, and more preferably 70% by mass to 95% by mass. When solids are not easily generated, the liquid is not turbid, pot life is not easily deteriorated, the molecular weight is easily controlled (suppressing the increase in molecular weight), or the content of polymerizable groups is sufficient, and the polymerization process is performed. The content of the organosilane containing the vinyl polymerizable group is preferably 30% by mass or more from the viewpoint of easily improving the performance (for example, scratch resistance of the antireflection film). When synthesizing the compound represented by the general formula 1, (M-1) and (M-2) as the organosilane containing the vinyl polymerizable group, and (MM) as the organosilane having no vinyl polymerizable group. It is preferable to use one of each of −19) to (M-21) and (M-48) in combination with the above amounts.

  At least one of the hydrolyzate of organosilane of the present invention and its partial condensate is preferably suppressed in terms of volatility in order to stabilize the performance of the coated product, specifically, at 105 ° C. per hour. The volatilization amount is preferably 5% by mass or less, more preferably 3% by mass or less, and particularly preferably 1% by mass or less.

The hydrolyzate and partial condensate of the organosilane compound used in the present invention will be described in detail.
The hydrolysis reaction of organosilane and the subsequent condensation reaction are generally carried out in the presence of a catalyst. Catalysts include inorganic acids such as hydrochloric acid, sulfuric acid and nitric acid; organic acids such as oxalic acid, acetic acid, butyric acid, maleic acid, citric acid, formic acid, methanesulfonic acid and toluenesulfonic acid; sodium hydroxide, potassium hydroxide and ammonia Inorganic bases such as triethylamine, pyridine, etc .; metal alkoxides such as triisopropoxyaluminum, tetrabutoxyzirconium, tetrabutyltitanate, dibutyltin dilaurate; metals such as Zr, Ti or Al Metal chelate compounds and the like; F-containing compounds such as KF and NH ₄ F may be mentioned.
The said catalyst may be used independently or may use multiple types together.

  Among inorganic acids, hydrochloric acid, sulfuric acid, and organic acids preferably have an acid dissociation constant in water (pKa value (25 ° C.)) of 4.5 or less, and an acid dissociation constant in hydrochloric acid, sulfuric acid, or water of 3.0 or less. More preferred is an organic acid, hydrochloric acid, sulfuric acid, an organic acid having an acid dissociation constant of 2.5 or less in water is more preferred, an organic acid having an acid dissociation constant in water of 2.5 or less is more preferred, and methanesulfonic acid Further, oxalic acid, phthalic acid, and malonic acid are more preferable, and oxalic acid is particularly preferable.

The organosilane hydrolysis / condensation reaction can be carried out in the absence of a solvent or in a solvent, but an organic solvent is preferably used in order to mix the components uniformly. For example, alcohols, aromatic hydrocarbons, ethers, Ketones and esters are preferred.
The solvent preferably dissolves the organosilane and the catalyst. In addition, it is preferable in the process that an organic solvent is used as a coating liquid or a part of the coating liquid, and those that do not impair solubility or dispersibility when mixed with other materials such as a fluorine-containing polymer are preferable.

Among these, examples of the alcohols include monohydric alcohols and dihydric alcohols. Among these, monohydric alcohols are preferably saturated aliphatic alcohols having 1 to 8 carbon atoms.
Specific examples of these alcohols include methanol, ethanol, n-propyl alcohol, i-propyl alcohol, n-butyl alcohol, sec-butyl alcohol, tert-butyl alcohol, ethylene glycol, diethylene glycol, triethylene glycol, ethylene glycol. Examples thereof include monobutyl ether and ethylene glycol monoethyl ether acetate.

Specific examples of aromatic hydrocarbons include benzene, toluene and xylene, specific examples of ethers include tetrahydrofuran and dioxane, and specific examples of ketones include acetone, methyl ethyl ketone, and methyl isobutyl ketone. Specific examples of esters such as diisobutylketone and the like include ethyl acetate, propyl acetate, butyl acetate, and propylene carbonate.
These organic solvents can be used alone or in combination of two or more. The concentration of the solid content in the reaction is not particularly limited, but is usually in the range of 1% to 100%, more preferably in the range of 1% to 90%, and particularly preferably in the range of 20% to 70%. It is.

  In the hydrolysis / condensation reaction of organosilane, 0.05 to 2 mol, preferably 0.1 to 1 mol of water is added to 1 mol of hydrolyzable group of organosilane, and in the presence or absence of the above solvent. It is carried out by stirring at 25-100 ° C. in the presence and in the presence of a catalyst.

The weight average molecular weight of the organosilane hydrolyzate containing a vinyl polymerizable group and the partial condensate thereof is preferably 450 to 20000, more preferably 500 to 10,000, and more preferably 550, when a component having a molecular weight of less than 300 is excluded. 5000 is more preferable, 600-300
0 is more preferable.
Of the components having a molecular weight of 300 or more in the hydrolyzate of organosilane and its partial condensate, the component having a molecular weight of more than 20000 is preferably 20% by mass or less, more preferably 10% by mass or less. More preferably, it is at most mass%.
Moreover, it is preferable that the component of molecular weight 1000-20000 is 20 mass% or more among the components of molecular weight 300 or more in the hydrolyzate of organosilane and its partial condensate. When it is 20% by mass or more, a cured film obtained by curing such a curable composition containing a hydrolyzate of organosilane and a partial condensate thereof is excellent in transparency and adhesion to a substrate.

Here, the weight average molecular weight and molecular weight were converted to polystyrene by GTH analyzer using a column of TSKgel GMHxL, TSKgel G4000HxL, TSKgel G2000HxL (both trade names manufactured by Tosoh Corporation), and solvent THF and differential refractometer detection. The content is the area% of the peak in the molecular weight range when the peak area of the component having a molecular weight of 300 or more is defined as 100%.
The dispersity (weight average molecule / number average molecular weight) is preferably 3.0 to 1.1, more preferably 2.5 to 1.1, still more preferably 2.0 to 1.1, and 1.5 to 1. 1 is particularly preferred.

By ²⁹ Si-NMR analysis of the hydrolyzate and partial condensate of organosilane, it can be confirmed that X in the general formula 4 is condensed in the form of -OSi.
At this time, when three bonds of Si are condensed in the form of -OSi (T3), when two bonds of Si are condensed in the form of -OSi (T2), one bond of Si is- When the condensation is performed in the form of OSi (T1), and the case where Si is not condensed at all (T0), the condensation rate α is expressed by the formula (XIII): α = (T3 × 3 + T2 × 2 + T1 × 1) / 3 / (T3 + T2 + T1 + T0)
The condensation rate is preferably 0.2 to 0.95, more preferably 0.3 to 0.93, and particularly preferably 0.4 to 0.9.
If it is less than 0.1, hydrolysis and condensation are not sufficient, and monomer components increase, so that curing is not sufficient. If it is greater than 0.95, hydrolysis and condensation proceed too much and hydrolyzable groups are consumed. For this reason, the interaction between the binder polymer, the resin substrate, the inorganic fine particles and the like is lowered, and even if these are used, it is difficult to obtain the effect.

In the present invention, (wherein, ^{R 3} represents an alkyl group having 1 to 10 carbon atoms) Formula ^R 3 OH alcohol of the general formula ^R 4 COCH ₂ COR ⁵ (formula represented by, ^{R 4} is carbon From Zr, Ti, or Al having a ligand represented by a compound represented by an alkyl group having 1 to 10 carbon atoms, R ⁵ represents an alkyl group having 1 to 10 carbon atoms or an alkoxy group having 1 to 10 carbon atoms) Hydrolysis is preferably performed by stirring at 25 to 100 ° C. in the presence of at least one metal chelate compound having a selected metal as a central metal. Alternatively, when an F-containing compound is used for the catalyst, the F-containing compound has the ability to completely proceed with hydrolysis and condensation, so the degree of polymerization can be determined by selecting the amount of water to be added, and any molecular weight can be set Therefore, it is preferable. That is, in order to adjust the organosilane hydrolyzate / partial condensate having an average degree of polymerization M, (M-1) mol of water may be used with respect to M mol of hydrolyzable organosilane.

Metal chelate compounds (wherein, _{R 3} represents an alkyl group having 1 to 10 carbon atoms) Formula ^R 3 OH alcohol and ^R 4 COCH ₂ COR ⁵ (wherein represented by, ^{R 4} is C 1 -C To 10 alkyl groups, R ⁵ represents an alkyl group having 1 to 10 carbon atoms or an alkoxy group having 1 to 10 carbon atoms), and is selected from Zr, Ti, and Al. Any metal having a metal as a central metal can be suitably used without particular limitation. Within this category, two or more metal chelate compounds may be used in combination. The metal chelate compound used in the present invention has the general formula Zr (OR ³ ) _p1 (R ⁴ COCHCOR ⁵ ) _p2 , Ti (OR ³ ) _q1 (R ₄ COCHCOR ⁵ ) _q2 , and Al (OR ³ ) _r1 (R ⁴ Those selected from the group of compounds represented by COCHCOR ⁵ ) _r2 are preferred, and they serve to promote the condensation reaction of the hydrolyzate and partial condensate of the organosilane compound.
R ³ and R ⁴ in the metal chelate compound may be the same or different and each is an alkyl group having 1 to 10 carbon atoms, specifically, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, sec -Butyl group, t-butyl group, n-pentyl group, phenyl group and the like. R ⁵ represents an alkyl group having 1 to 10 carbon atoms as described above, or an alkoxy group having 1 to 10 carbon atoms such as a methoxy group, an ethoxy group, an n-propoxy group, an i-propoxy group, and n-butoxy. Group, sec-butoxy group, t-butoxy group and the like. Moreover, p1, p2, q1, q2, r1, and r2 in the metal chelate compound represent integers determined so as to be p1 + p2 = 4, q1 + q2 = 4, and r1 + r2 = 3, respectively.

Specific examples of these metal chelate compounds include tri-n-butoxyethyl acetoacetate zirconium, di-n-butoxybis (ethylacetoacetate) zirconium, n-butoxytris (ethylacetoacetate) zirconium, tetrakis (n-propylacetate). Zirconium chelate compounds such as acetate) zirconium, tetrakis (acetylacetoacetate) zirconium, tetrakis (ethylacetoacetate) zirconium; diisopropoxy bis (ethylacetoacetate) titanium, diisopropoxy bis (acetylacetate) titanium, diiso Titanium chelate compounds such as propoxy bis (acetylacetone) titanium; diisopropoxyethyl acetoacetate aluminum, diisopropyl Poxyacetylacetonate aluminum, isopropoxybis (ethylacetoacetate) aluminum, isopropoxybis (acetylacetonate) aluminum, tris (ethylacetoacetate) aluminum, tris (acetylacetonato) aluminum, monoacetylacetonate bis (ethyl) An aluminum chelate compound such as acetoacetate) aluminum.
Among these metal chelate compounds, tri-n-butoxyethyl acetoacetate zirconium, diisopropoxybis (acetylacetonato) titanium, diisopropoxyethyl acetoacetate aluminum, and tris (ethyl acetoacetate) aluminum are preferable. These metal chelate compounds can be used individually by 1 type or in mixture of 2 or more types. Moreover, the partial hydrolyzate of these metal chelate compounds can also be used.

  The metal chelate compound is preferably used in a proportion of 0.01 to 50% by mass, more preferably 0.1 to 50% by mass, and still more preferably 0.5 to 10% by mass with respect to the organosilane compound. By using the metal chelate compound in the above range, the condensation reaction of the organosilane compound is fast, the durability of the coating film is good, and the hydrolyzate and partial condensate of the organosilane compound and the metal chelate compound are contained. The storage stability of the composition is good.

  In addition to the composition containing the sol component and the metal chelate compound, at least one of a β-diketone compound and a β-ketoester compound may be added to the functional layer coating solution used in the optical film of the present invention. preferable. This will be further described below.

In the present invention, at least one of a β-diketone compound and a β-ketoester compound represented by the general formula R ⁴ COCH ₂ COR ⁵ is used as a stability improver for the composition used in the present invention. It works. That is, by coordinating with a metal atom in the metal chelate compound (at least one of zirconium, titanium and aluminum compounds), condensation of hydrolyzate and partial condensate of organosilane compound by these metal chelate compounds It is considered that the action of accelerating the reaction is suppressed and the action of improving the storage stability of the resulting composition is achieved. R ⁴ and R ⁵ constituting the β- diketone compound and β- ketoester compound are the same as R ⁴ and R ⁵ constituting the metal chelate compound.

  Specific examples of the β-diketone compound and β-ketoester compound include acetylacetone, methyl acetoacetate, ethyl acetoacetate, acetoacetate-n-propyl, acetoacetate-i-propyl, acetoacetate-n-butyl, acetoacetate- sec-butyl, acetoacetate-t-butyl, 2,4-hexane-dione, 2,4-heptane-dione, 3,5-heptane-dione, 2,4-octane-dione, 2,4-nonane-dione , 5-methyl-hexane-dione and the like. Of these, ethyl acetoacetate and acetylacetone are preferred, and acetylacetone is particularly preferred. These β-diketone compounds and β-ketoester compounds can be used alone or in admixture of two or more. In the present invention, the β-diketone compound and the β-ketoester compound are preferably used in an amount of 2 mol or more, more preferably 3 to 20 mol, per 1 mol of the metal chelate compound. If it is less than 2 mol, the storage stability of the resulting composition may be inferior, which is not preferable.

The content of the hydrolyzate and partial condensate of the organosilane compound is preferably small in the case of a relatively thin antireflection layer and large in the case of a thick hard coat layer or antiglare layer. The content is preferably 0.1 to 50% by mass, and preferably 0.5 to 30% by mass based on the total solid content of the containing layer (added layer), considering the effect, refractive index, film shape / surface shape, and the like. More preferred is 1 to 15% by mass.
In the present invention, first, a composition containing at least one of the hydrolyzate and partial condensate of the organosilane compound and a metal chelate compound is prepared. It is preferable to coat the liquid containing the above in a coating liquid containing at least one layer of a hard coat layer or a low refractive index layer.

(Surfactant)
In addition, for the coating solution of the present invention, in order to improve coating properties, uniform drying, and impart high-speed coating suitability, either or both of a fluorine-based component and a silicone-based component having a surfactant activity are coated. It is preferable to add to the composition. These surface active components may be added for surface wettability, antifouling property, dustproof property, chargeability adjustment and the like.

  Preferable examples of the silicone compound include those having a substituent at at least one of the end of the compound chain and the side chain, which contains a plurality of dimethylsilyloxy units as repeating units. The compound chain containing dimethylsilyloxy as a repeating unit may contain a structural unit other than dimethylsilyloxy. The substituents may be the same or different, and a plurality of substituents are preferable. Examples of preferred substituents include acryloyl group, methacryloyl group, vinyl group, aryl group, cinnamoyl group, epoxy group, oxetanyl group, hydroxyl group, fluoroalkyl group, polyoxyalkylene group, carboxyl group, amino group and the like. Can be mentioned.

  Although there is no restriction | limiting in particular in the molecular weight of a silicone type compound, It is preferable that it is 100,000 or less, It is especially preferable that it is 50,000 or less, It is most preferable that it is 3000-30000. The silicone atom content of the silicone compound is not particularly limited, but is preferably 18.0% by mass or more, particularly preferably 25.0 to 37.8% by mass, and 30.0 to 37. Most preferably, it is 0.0 mass%.

  Examples of preferable silicone compounds include, but are not limited to, those described in paragraph No. [0068] of JP-A-2004-42278.

A compound containing a fluoroalkyl group is also preferred as an additive. The fluoroalkyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, and a straight chain [eg, —CF ₂ CF ₃ , —CH ₂ (CF ₂ ) ₄ H, —CH ₂ (CF ₂ ) ₈ CF ₃ , —CH ₂ CH ₂ (CF ₂ ) ₄ H, etc.], but branched structures [eg, —CH (CF ₃ ) ₂ , —CH ₂ CF (CF ₃ ) ₂ , —CH (CH ₃ ) CF ₂ CF ₃ , —CH (CH ₃ ) (CF ₂ ) ₅ CF ₂ H, etc.], an alicyclic structure (preferably a 5- or 6-membered ring such as a perfluorocyclohexyl group). , A perfluorocyclopentyl group or an alkyl group substituted with these, and may have an ether bond (for example, —CH ₂ OCH ₂ CF ₂ CF ₃ , —CH ₂ CH ₂ OCH ₂ C). ₄ F ₈ H, - _{H 2 CH 2 OCH 2 CH 2} C 8 F 17, -CH 2 CH 2 OCF 2 CF 2 OCF 2 CF 2 H , etc.). A plurality of the fluoroalkyl groups may be contained in the same molecule.

  The fluorine-based compound may be a polymer or an oligomer with a compound not containing a fluorine atom, and the molecular weight is not particularly limited and is used. Although there is no restriction | limiting in particular in fluorine atom content of a fluorine-type compound, It is preferable that it is 20 mass% or more, It is especially preferable that it is 30-70 mass%, It is most preferable that it is 40-70 mass%. Examples of preferable fluorine-based compounds include “R-2020”, “M-2020”, “R-3833”, “M-3833” [trade name: manufactured by Daikin Chemical Industries, Ltd.]; -171, F-172, F-179A, F-780-F, defender MCF-300 [trade name: manufactured by Dainippon Ink, Inc.] and the like, but are not limited thereto.

  Of the above additives, it is particularly preferable to contain a fluoroalkyl group-containing copolymer in the coating composition. This fluoroalkyl group-containing copolymer is preferable because an effect of improving surface defects such as coating unevenness, drying unevenness, and point defects of an optical film appears with a smaller addition amount.

  Furthermore, by selecting the structure of the following fluoroalkyl group-containing copolymer, the copolymer unevenly distributed on the surface of the functional layer is extracted into the upper solvent when the upper layer (for example, a low refractive index layer) is applied, thereby preventing the antireflection of the present invention. When the film is formed, it is also preferable not to exist on the functional layer surface (functional layer interface). Moreover, adjusting the addition amount of the fluoroaliphatic group-containing copolymer is also effective in improving the above effect.

  Specifically, such a method includes adding a fluoroaliphatic group-containing copolymer containing 10% by mass or more of a polymer unit of a fluoroaliphatic group-containing monomer in the coating solution, and then adding the fluoroaliphatic group-containing copolymer. In order to segregate the surface (conforms to the uneven distribution and consent) and to obtain adhesion with the upper layer, a solvent of a coating solution for forming the upper layer is applied on the functional layer containing the fluoroaliphatic group-containing copolymer. In this method, the surface free energy of the functional layer is changed by 1 mN / m or more by drying, particularly 3 mN / m or more.

Fluoroaliphatic group-containing copolymer (sometimes abbreviated as "fluorine-based polymer") is fluoroalkyl having a perfluoroalkyl group or a C 4+ CF 2 _H- group carbon number of 4 or more carbon atoms in a side chain A copolymer having a group is preferred.
Among them, an acrylic resin, a methacrylic resin, and a copolymerizable with the repeating unit (polymerized unit) corresponding to the monomer (i) below and the repeating unit (polymerized unit) corresponding to the monomer (ii) below. Copolymers with vinyl monomers are useful. Examples of such monomers include Polymer Handbook 2nd ed. , J .; Brandrup, Wiley interscience (1975) Chapter 2 Pages 1-483 can be used.
For example, acrylic acid, methacrylic acid, acrylic acid esters, methacrylic acid esters,
Examples thereof include compounds having one addition polymerizable unsaturated bond selected from acrylamides, methacrylamides, allyl compounds, vinyl ethers, vinyl esters and the like.

(I) Fluoroaliphatic group-containing monomer represented by the following general formula 6

In the general formula 6, R ¹ represents a hydrogen atom, a halogen atom or a methyl group, preferably a hydrogen atom or a methyl group. X represents an oxygen atom, a sulfur atom or —N (R ¹² ) —, more preferably an oxygen atom or —N (R ¹² ) —, and still more preferably an oxygen atom. R ¹² represents a hydrogen atom or an optionally substituted alkyl group having 1 to 8 carbon atoms, more preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and further preferably a hydrogen atom or a methyl group. R _f represents —CF ₃ or —CF ₂ H.
M in the general formula 6 represents an integer of 1 to 6, more preferably 1 to 3, and still more preferably 1.
N in the general formula 6 represents an integer of 1 to 17, more preferably 4 to 11, and still more preferably 6 to 7. R _f is preferably —CF ₂ H.
Two or more kinds of polymer units derived from the fluoroaliphatic group-containing monomer represented by the general formula 6 may be contained in the fluorine-based polymer as a constituent component.

(Ii) Monomer represented by the following general formula 7 copolymerizable with the above (i)

In the general formula 7, R ¹³ represents a hydrogen atom, a halogen atom or a methyl group, a hydrogen atom, more preferably a methyl group. Y represents an oxygen atom, a sulfur atom or —N (R ¹⁵ ) —, more preferably an oxygen atom or —N (R ¹⁵ ) —, and still more preferably an oxygen atom. R ¹⁵ represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms, more preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and still more preferably a hydrogen atom or a methyl group.
R ¹⁴ is a linear, branched, or cyclic alkyl group having 1 to 60 carbon atoms that may have a substituent, or an aromatic group that may have a substituent (for example, a phenyl group or a naphthyl group). ). The alkyl group may include a poly (alkyleneoxy) group. A linear, branched or cyclic alkyl group having 1 to 12 carbon atoms, an alkyl group containing a poly (alkyleneoxy) group having 5 to 40 carbon atoms, or an aromatic group having 6 to 18 carbon atoms is more preferable. Alkyl groups including 8 linear, branched, or cyclic alkyl groups and poly (alkyleneoxy) groups having 5 to 30 carbon atoms are highly preferred. The poly (alkyleneoxy) group will be described below.

Poly (alkyleneoxy) groups can be represented by (OR) x, R is an alkylene group having 2 to 4 carbon atoms, such as _{-CH 2 CH 2 -, - CH} 2 CH 2 CH 2 -, - CH It is preferably (CH ₃ ) CH ₂ — or —CH (CH ₃ ) CH (CH ₃ ) —. x represents 2-30, 2-20 are preferable and 4-15 are more preferable.
The oxyalkylene units in the poly (oxyalkylene) group may be the same as in poly (oxypropylene), or two or more different oxyalkylenes may be randomly distributed. It may be a linear or branched oxypropylene or oxyethylene unit, or a linear or branched oxypropylene unit block and an oxyethylene unit block.
The poly (oxyalkylene) chain may also include those linked by one or more chain bonds (for example, —CONH—Ph—NHCO—, —S—, etc .: Ph represents a phenylene group). If the chain bond has a valence of 3 or more, this provides a means for obtaining branched oxyalkylene units. When this copolymer is used in the present invention, the molecular weight of the poly (oxyalkylene) group is suitably from 250 to 3,000.
Poly (oxyalkylene) acrylates and methacrylates are commercially available hydroxypoly (oxyalkylene) materials such as trade name “Pluronic” (manufactured by Asahi Denka Kogyo Co., Ltd.), Adeka polyether (manufactured by Asahi Denka Kogyo Co., Ltd.). ) "Carbowax (Glyco Products)", "Triton" [Toriton (Rohm and Haas) and PEG (Daiichi Kogyo Seiyaku Co., Ltd.) Can be produced by reacting them with acrylic acid, methacrylic acid, acrylic chloride, methacrylic chloride or acrylic anhydride, etc. Separately, poly (oxyalkylene) diacrylate produced by a known method is used. You can also.

  The amount of the fluoroaliphatic group-containing monomer represented by the general formula 6 used in the production of the fluoropolymer used in the present invention is 10% by mass or more based on the total amount of the fluoropolymer monomer, Preferably it is 50 mass% or more, More preferably, it is 70-100 mass%, More preferably, it is the range of 80-100 mass%.

The preferred weight average molecular weight of the fluoropolymer used in the present invention is preferably 3000 to 100,000, more preferably 6,000 to 80,000, and still more preferably 8,000 to 60,000.
Here, the mass average molecular weight and the molecular weight were converted to polystyrene by GTH analyzer using a column of TSKgel GMHxL, TSKgel G4000HxL, TSKgel G2000HxL (both trade names manufactured by Tosoh Corp.), and detection by solvent THF and differential refractometer. Is the molecular weight. The molecular weight was calculated from the peak area of 300 or more components.

  Furthermore, the preferable addition amount of the fluorine-based polymer used in the present invention is 0.001 to 5 mass with respect to the mass of the coating solution from the viewpoint of expression of the effect due to the addition, drying, and suppression of occurrence of surface failure. %, Preferably 0.005 to 3% by mass, and more preferably 0.01 to 1% by mass.

  Hereinafter, examples of specific structures of the fluorine-based polymer according to the present invention are shown, but the present invention is not limited thereto. In addition, the number in a formula shows the molar ratio of each monomer component. Mw represents a mass average molecular weight.

  In addition, additives for purposes such as antistatic properties, conductivity, and hardness adjustment can also be used in the antiglare hard coat layer of the present invention.

The above antiglare hard coat film of the present invention preferably has a film thickness of 0.5 μm or more and 20 μm or less in order to impart physical strength and antiglare properties. More preferably, they are 0.7 micrometer or more and 15 micrometers or less, Most preferably, they are 1 micrometer or more and 10 micrometers or less. Moreover, the coating thickness as a coating film when applying these layers is set according to the concentration, viscosity, drying property, etc. of the coating solution, but preferably 1 cc to 40 cc per 1 m ² , more preferably ² cc to 30 cc. In particular, 5 to 25 cc is preferable. The cellulose acylate film of the present invention and the improvement effect due to the selection of the solvent composition are effective even in a region where the coating amount is small, but the effect is particularly large in a region where the coating amount is large, and more preferably 10 cc to 25 cc.

[Light diffusion layer]
The purpose of the light diffusing layer in the optical functional film of the present invention is to enlarge the viewing angle (particularly the downward viewing angle) of the liquid crystal display device and to reduce contrast, gradation or black-and-white reversal, even if the viewing angle in the viewing direction changes. It is to suppress the hue change.
The present inventors have confirmed that the intensity distribution of scattered light measured with a goniophotometer correlates with the viewing angle improvement effect. That is, as the light emitted from the backlight is diffused by the effect of internal scattering of the translucent fine particles contained in the light diffusion film installed on the surface of the polarizing plate on the viewing side, the viewing angle characteristics are improved. However, if it is diffused too much, backscattering will increase and the front luminance will decrease, or the scattering will be too great and the image clarity will deteriorate. Therefore, it is necessary to control the scattered light intensity distribution within a certain range. Therefore, as a result of intensive studies, in order to achieve the desired visual characteristics, the scattered light intensity at 30 °, which correlates particularly with the visual angle improvement effect, is 0.01 with respect to the light intensity at the output angle 0 ° of the scattered light profile. % To 0.2% is preferable, 0.02% to 0.15% is more preferable, and 0.03% to 0.1% is particularly preferable.
The scattered light profile can be measured using the automatic variable angle photometer GP-5 manufactured by Murakami Color Research Laboratory Co., Ltd. for the created light scattering film.

  The light diffusing layer of the present invention is formed from a binder, an inorganic filler, and translucent fine particles, and the binder and the inorganic filler can be the same as those described above for the antiglare hard coat layer. The same is used.

  The binder of the light diffusing layer is added in an amount of 5 to 80% by mass based on the solid content of the coating composition of the layer.

  The light diffusion layer of the present invention preferably has a hard coat function. In this light diffusion layer, the binder, initiator, particles, and other additives described in the antiglare hard coat layer can be used in the same manner.

[High refractive index layer]
In the antireflection film of the present invention, a high refractive index layer can be preferably used in order to impart better antireflection performance.

(Inorganic fine particles mainly composed of titanium dioxide)
The high refractive index layer of the present invention contains inorganic fine particles mainly composed of titanium dioxide containing at least one element selected from cobalt, aluminum, and zirconium. The main component means a component having the largest content (mass%) among the components constituting the particles.
The refractive index of the high refractive index layer of the present invention is a refractive index of 1.55 to 2.40, which is a so-called high refractive index layer or a medium refractive index layer. The layer may be collectively referred to as a high refractive index layer.
The inorganic fine particles mainly composed of titanium dioxide in the present invention preferably have a refractive index of 1.90 to 2.80, more preferably 2.10 to 2.80, and 2.20 to 2.80. 80 is most preferred.
The mass average diameter of primary particles of inorganic fine particles mainly composed of titanium dioxide is preferably 1 to 200 nm, more preferably 1 to 150 nm, still more preferably 1 to 100 nm, and particularly preferably 1 to 80 nm.

The particle diameter of the inorganic fine particles can be measured by a light scattering method or an electron micrograph. The specific surface area of the inorganic fine particles is preferably 10 to 400 m ² / g, more preferably from 20 to 200 m ² / g, and most preferably from 30 to 150 m ² / g.
The crystal structure of the inorganic fine particles containing titanium dioxide as a main component is preferably a rutile, rutile / anatase mixed crystal, anatase or amorphous structure, particularly preferably a rutile structure. The main component means a component having the largest content (mass%) among the components constituting the particles.

By containing at least one element selected from Co, Al and Zr in the inorganic fine particles mainly composed of titanium dioxide, the photocatalytic activity of titanium dioxide can be suppressed, and the weather resistance of the high refractive index layer of the present invention Can be improved.
In particular, the preferred element is Co. It is also preferable to use two or more types in combination.
The content of Co, Al or Zr with respect to Ti is preferably 0.05 to 30% by mass, more preferably 0.1 to 10% by mass, and further preferably 0.2 to 7% by mass with respect to Ti. %, Particularly preferably 0.3 to 5% by mass, most preferably 0.5 to 3% by mass.
Co, Al, and Zr can be present in at least one of the inside and the surface of the inorganic fine particles mainly composed of titanium dioxide, but are preferably present inside the inorganic fine particles mainly composed of titanium dioxide. Most preferably it is present both inside and on the surface.
There are various methods for causing Co, Al, and Zr to exist (for example, dope) in the inorganic fine particles mainly composed of titanium dioxide. For example, an ion implantation method (Vol. 18, No. 5, pp. 262-268, 1998; Yasushi Aoki), JP-A-11-263620, JP-A-11-512336, European Patent Application No. 0335773. And the method described in JP-A-5-330825.
Techniques for introducing Co, Al, and Zr in the process of forming inorganic fine particles containing titanium dioxide as a main component (for example, Japanese Patent Application Laid-Open No. 11-512336, European Patent Application Publication No. 0335773, Japanese Patent Application Laid-Open No. Hei 5- No. 330308) is particularly preferable.
Co, Al, and Zr are also preferably present as oxides.
The inorganic fine particles containing titanium dioxide as the main component can further contain other elements depending on the purpose. Other elements may be included as impurities. Examples of other elements include Sn, Sb, Cu, Fe, Mn, Pb, Cd, As, Cr, Hg, Zn, Mg, Si, P, and S.

The inorganic fine particles mainly composed of titanium dioxide used in the present invention may be surface-treated. The surface treatment is performed using an inorganic compound or an organic compound. Examples of inorganic compounds used for the surface treatment include inorganic compounds containing cobalt (CoO ₂ , Co ₂ O ₃ , Co ₃ O _4, etc.) and inorganic compounds containing aluminum (Al ₂ O ₃ , Al (OH) ₃ Etc.), zirconium-containing inorganic compounds (such as ZrO ₂ and Zr (OH) ₄ ), silicon-containing inorganic compounds (such as SiO ₂ ), and iron-containing inorganic compounds (such as Fe ₂ O ₃ ). .
An inorganic compound containing cobalt, an inorganic compound containing aluminum, and an inorganic compound containing zirconium are particularly preferable, and an inorganic compound containing cobalt, Al (OH) ₃ , and Zr (OH) ₄ are most preferable.
Examples of organic compounds used for the surface treatment include polyols, alkanolamines, stearic acid, silane coupling agents, and titanate coupling agents. Silane coupling agents are most preferred.

Examples of titanate coupling agents include metal alkoxides such as tetramethoxy titanium, tetraethoxy titanium, and throat tetraisopropoxy titanium, and preneact (KR-TTS, KR-46B, KR-55, KR-41B, etc .; Ajinomoto Co., Inc. ))).
Examples of the organic compound used for the surface treatment include polyols, alkanolamines, and other organic compounds having an anionic group, and particularly preferable are organic compounds having a carboxyl group, a sulfonic acid group, or a phosphoric acid group. is there.
Stearic acid, lauric acid, oleic acid, linoleic acid, linolenic acid and the like can be preferably used.
The organic compound used for the surface treatment preferably further has a crosslinked or polymerizable functional group. Crosslinkable or polymerizable functional groups include ethylenically unsaturated groups (for example, (meth) acrylic groups, allyl groups, styryl groups, vinyloxy groups, etc.) that can undergo addition reactions and polymerization reactions with radical species, cationic polymerizable groups (Epoxy groups, oxatanyl groups, vinyloxy groups, etc.), polycondensation reactive groups (hydrolyzable silyl groups, etc., N-methylol groups) and the like can be mentioned, and groups having an ethylenically unsaturated group are preferred.

Two or more kinds of these surface treatments can be used in combination. It is particularly preferable to use an inorganic compound containing aluminum and an inorganic compound containing zirconium in combination.
The inorganic fine particles mainly composed of titanium dioxide of the present invention may have a core / shell structure by surface treatment as described in JP-A No. 2001-166104.

  The shape of the inorganic fine particles mainly composed of titanium dioxide contained in the high refractive index layer is preferably a rice grain shape, a spherical shape, a cubic shape, a spindle shape or an indefinite shape, and particularly preferably an indefinite shape or a spindle shape. is there.

(Dispersant)
A dispersant can be used to disperse the inorganic fine particles mainly composed of titanium dioxide used in the high refractive index layer of the present invention.
In order to disperse the inorganic fine particles mainly composed of titanium dioxide of the present invention, it is particularly preferable to use a dispersant having an anionic group.
As the anionic group, a group having an acidic proton such as a carboxyl group, a sulfonic acid group (and a sulfo group), a phosphoric acid group (and a phosphono group), or a sulfonamide group, or a salt thereof is effective. A sulfonic acid group, a phosphoric acid group and a salt thereof are preferable, and a carboxyl group and a phosphoric acid group are particularly preferable. The number of anionic groups contained in the dispersant per molecule may be one or more.
A plurality of anionic groups may be contained for the purpose of further improving the dispersibility of the inorganic fine particles. The average number is preferably 2 or more, more preferably 5 or more, and particularly preferably 10 or more. Moreover, the anionic group contained in a dispersing agent may contain multiple types in 1 molecule.

The dispersant preferably further contains a crosslinkable or polymerizable functional group. Crosslinkable or polymerizable functional groups include ethylenically unsaturated groups (for example, (meth) acryloyl groups, allyl groups, styryl groups, vinyloxy groups, etc.) that can undergo addition reactions and polymerization reactions with radical species, and cationic polymerizable groups (epoxies). Groups, oxatanyl groups, vinyloxy groups, etc.), polycondensation reactive groups (hydrolyzable silyl groups, etc., N-methylol groups) and the like, and functional groups having an ethylenically unsaturated group are preferred.
A preferred dispersant used for dispersion of inorganic fine particles mainly composed of titanium dioxide used in the high refractive index layer of the present invention has an anionic group and a crosslinkable or polymerizable functional group, and the crosslinkable or polymerizable functional group. In the side chain.
The weight average molecular weight (Mw) of the dispersant having an anionic group and a crosslinkable or polymerizable functional group and having the crosslinkable or polymerizable functional group in the side chain is not particularly limited, but is preferably 1000 or more. . The more preferable mass average molecular weight (Mw) of the dispersant is 2,000 to 1,000,000, more preferably 5,000 to 200,000, and particularly preferably 10,000 to 100,000.

As the anionic group, a group having an acidic proton such as a carboxyl group, a sulfonic acid group (sulfo), a phosphoric acid group (phosphono), a sulfonamide group, or a salt thereof is effective, and in particular, a carboxyl group, a sulfonic acid group, A phosphoric acid group or a salt thereof is preferable, and a carboxyl group and a phosphoric acid group are particularly preferable. The average number of anionic groups contained in the dispersant per molecule is preferably 2 or more, more preferably 5 or more, and particularly preferably 10 or more. Moreover, the anionic group contained in a dispersing agent may contain multiple types in 1 molecule.

The dispersant having an anionic group and a crosslinkable or polymerizable functional group and having the crosslinkable or polymerizable functional group in the side chain has the anionic group in the side chain or terminal.
Particularly preferred dispersants are those having an anionic group in the side chain. In the dispersant having an anionic group in the side chain, the composition of the anionic group-containing repeating unit is in the range of 10 ^{−4 to} 100 mol%, preferably 1 to 50 mol%, particularly preferably 5 in the total repeating units. ˜20 mol%.

  Examples of the cross-linkable or polymerizable functional group include ethylenically unsaturated groups (for example, (meth) acryl group, allyl group, styryl group, vinyloxy group, etc.) capable of addition reaction / polymerization reaction with radical species, cationic polymerizable group (epoxy) Groups, oxatanyl groups, vinyloxy groups, etc.), polycondensation reactive groups (hydrolyzable silyl groups, etc., N-methylol groups), and the like. Preferred are groups having an ethylenically unsaturated group.

  The average number of cross-linkable or polymerizable functional groups contained in the dispersant per molecule is preferably 2 or more, more preferably 5 or more, and particularly preferably 10 or more. Moreover, the crosslinking or polymerizable functional group contained in the dispersant may contain a plurality of types in one molecule.

In the preferred dispersant for use in the present invention, examples of the repeating unit having an ethylenically unsaturated group in the side chain include poly-1,2-butadiene and poly-1,2-isoprene structures or (meth) acrylic acid. An ester or amide repeating unit to which a specific residue (the R group of —COOR or —CONHR) is bonded can be used. Examples of the specific residue (R _{group), - (CH 2) n} -CR 21 = CR 22 R 23, - (CH 2 O) n-CH 2 CR 21 = CR 22 R 23, - (CH _{2 CH 2 O) n-CH} 2 CR 21 = CR 22 R 23, - (CH 2) n-NH-CO-O-CH 2 CR 21 = CR 22 R 23, - (CH 2) n-O-CO —CR ₂₁ ═CR ₂₂ R ₂₃ and — (CH ₂ CH ₂ O) ₂ —X (R _{21 to} R ₂₃ are each a hydrogen atom, a halogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group, or an alkoxy group. R ₂₁ and R ₂₂ or R ₂₃ may be bonded to each other to form a ring, n is an integer of 1 to 10, and X is a dicyclopentadienyl residue. There are). Specific examples of R of the ester residue include —CH ₂ CH═CH ₂ (corresponding to an allyl (meth) acrylate polymer described in JP-A No. 64-17047), —CH ₂ CH ₂ O—CH ₂ CH. _{= CH 2, -CH 2 CH 2} OCOCH = CH 2, -CH 2 CH 2 OCOC (CH 3) = CH 2, -CH 2 C (CH 3) = CH 2, -CH 2 CH = CH-C 6 H ₅ , —CH ₂ CH ₂ OCOCH═CH—C ₆ H ₅ , —CH ₂ CH ₂ —NHCOO—CH ₂ CH═CH ₂ and —CH ₂ CH ₂ O—X (X is a dicyclopentadienyl residue) Is included. Specific examples of R of the amide residue include —CH ₂ CH═CH ₂ , —CH ₂ CH ₂ —Y (Y is a 1-cyclohexenyl residue) and —CH ₂ CH ₂ —OCO—CH═CH ₂ , _{-CH 2 CH 2 -OCO-C (} CH 3) = CH 2 are included.

  In the dispersant having an ethylenically unsaturated group, a free radical (a polymerization initiation radical or a growth radical of a polymerization process of a polymerizable compound) is added to the unsaturated bond group, and the polymer compound is directly or between molecules. Addition polymerization is carried out through the polymerization chain, and a crosslink is formed between the molecules to cure. Alternatively, atoms in the molecule (for example, hydrogen atoms on carbon atoms adjacent to the unsaturated bond group) are extracted by free radicals to form polymer radicals that are bonded together to form a bridge between the molecules. Harden.

The cross-linkable or polymerizable functional group-containing unit may constitute all repeating units other than the anionic group-containing repeating unit, preferably 5 to 50 mol% of the total cross-linking or repeating unit, particularly Preferably it is 5-30 mol%.
A preferable dispersant of the present invention may be a copolymer with an appropriate monomer other than a monomer having a crosslinkable or polymerizable functional group or an anionic group. Although it does not specifically limit regarding a copolymerization component, It selects from various viewpoints, such as dispersion stability, compatibility with another monomer component, and the intensity | strength of a formed film. Preferable examples include methyl (meth) acrylate, n-butyl (meth) acrylate, t-butyl (meth) acrylate, cyclohexyl (meth) acrylate, styrene and the like.
The preferred dispersant form of the present invention is not particularly limited, but is preferably a block copolymer or a random copolymer, and particularly preferably a random copolymer from the viewpoint of cost and synthetic ease.

  As the dispersant preferably used in the present invention, compounds described in “Chemical Formula 1” to “Chemical Formula 6” of JP-A-2004-29705 can be used. The dispersant for the present invention is not limited to these.

  The amount of the dispersant used relative to the inorganic fine particles is preferably in the range of 1 to 50% by mass, more preferably in the range of 5 to 30% by mass, and most preferably 5 to 20% by mass. Two or more dispersants may be used in combination.

(High refractive index layer and formation method thereof)
The inorganic fine particles mainly composed of titanium dioxide used for the high refractive index layer are used for forming the high refractive index layer in a dispersion state.
In the dispersion of the inorganic fine particles, it is dispersed in a dispersion medium in the presence of the dispersant.
As the dispersion medium, a liquid having a boiling point of 60 to 170 ° C. is preferably used. Examples of dispersion media include water, alcohol (eg, methanol, ethanol, isopropanol, butanol, benzyl alcohol), ketone (eg, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone), ester (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 Hydrocarbon (eg, benzene, toluene, xylene), amide (eg, dimethylformamide, dimethylacetamide, n-methylpyrrolidone), ether (eg, diethyl ether, dioxane, tetrahydrofuran), ether alcohol (eg, 1-methyl) Carboxymethyl-2-propanol) are included. Toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone and butanol are preferred.
Particularly preferred dispersion media are methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone and toluene.

The inorganic fine particles are dispersed using a disperser. Examples of dispersers include sand grinder mills (eg, pinned bead mills), high speed impeller mills, pebble mills, roller mills, attritors and colloid mills. 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.
The inorganic fine particles are preferably made as fine as possible in the dispersion medium, and the mass average diameter is 1 to 200 nm. Preferably it is 5-150 nm, More preferably, it is 10-100 nm, Most preferably, it is 10-80 nm.
By refining the inorganic fine particles to 200 nm or less, a high refractive index layer that does not impair the transparency can be formed.

  The high-refractive index layer used in the present invention is preferably added to the dispersion liquid in which the inorganic fine particles are dispersed in the dispersion medium as described above, preferably a binder precursor necessary for matrix formation (of the antiglare hard coat layer described above). The same as the binder precursor), a photopolymerization initiator, etc. are added to form a coating composition for forming a high refractive index layer, and the coating composition for forming a high refractive index layer is coated on a transparent support, and ionized. It is preferably formed by curing by a crosslinking reaction or a polymerization reaction of a radiation curable compound (for example, a polyfunctional monomer or a polyfunctional oligomer).

Furthermore, it is preferable to cause the binder of the high refractive index layer to undergo a crosslinking reaction or a polymerization reaction with the dispersant simultaneously with or after the coating of the layer.
The binder of the high refractive index layer produced in this way is, for example, the above-mentioned preferred dispersant and ionizing radiation-curable polyfunctional monomer or polyfunctional oligomer undergo a crosslinking or polymerization reaction, and the binder is anionic. The base is incorporated. Furthermore, the binder of the high refractive index layer has a function in which the anionic group maintains the dispersed state of the inorganic fine particles, and the cross-linked or polymerized structure imparts a film forming ability to the binder to contain the inorganic fine particles. Improves physical strength, chemical resistance, and weather resistance.

It is preferable to use a photopolymerization initiator for the polymerization reaction of the photopolymerizable polyfunctional monomer. As the photopolymerization initiator, a photoradical polymerization initiator and a photocationic polymerization initiator are preferable, and a photoradical polymerization initiator is particularly preferable.
As the radical photopolymerization initiator, the same antiglare hard coat layer as described above can be used.

In the high refractive index layer, the binder preferably further has a silanol group. When the binder further has a silanol group, the physical strength, chemical resistance, and weather resistance of the high refractive index layer are further improved.
For example, the silanol group may be obtained by applying the silane coupling agent represented by the general formula 4 having a crosslinkable or polymerizable functional group, a partial hydrolyzate thereof, or a condensate thereof to the above coating composition for forming a high refractive index layer. Then, the coating composition is coated on a transparent support, and the above-mentioned dispersant, polyfunctional monomer or polyfunctional oligomer, the silane coupling agent represented by the general formula 4, the partial hydrolyzate thereof, or the condensation thereof The product can be introduced into the binder by crosslinking reaction or polymerization reaction.

In the high refractive index layer, the binder preferably has an amino group or a quaternary ammonium group.
For the binder of the high refractive index layer having an amino group or quaternary ammonium group, for example, a monomer having a crosslinkable or polymerizable functional group and an amino group or quaternary ammonium group is added to the coating composition for forming the above high refractive index layer. And it can form by apply | coating a coating composition on a transparent support body, carrying out a crosslinking reaction or a polymerization reaction with said dispersing agent, a polyfunctional monomer, and a polyfunctional oligomer.

  A monomer having an amino group or a quaternary ammonium group functions as a dispersion aid for inorganic fine particles in the coating composition. Furthermore, after coating, a dispersant, a polyfunctional monomer or a polyfunctional oligomer is crosslinked or polymerized to form a binder, thereby maintaining good dispersibility of the inorganic fine particles in the high refractive index layer, physical strength, resistance A high refractive index layer excellent in chemical properties and weather resistance can be produced.

Preferred monomers having an amino group or a quaternary ammonium group include N, N-dimethylaminoethyl (meth) acrylate, N, N-dimethylaminopropyl (meth) acrylate, (meth) acrylic acid hydroxypropyltrimethylammonium chloride,
Examples thereof include dimethylallylammonium chloride.
It is preferable that the usage-amount with respect to the dispersing agent of the monomer which has an amino group or a quaternary ammonium group is 1-40 mass%, More preferably, it is 3-30 mass%, Most preferably, it is 3-20 mass%. If the binder is formed by crosslinking or polymerization reaction simultaneously with or after the application of the high refractive index layer, these monomers can be effectively functioned before the application of the high refractive index layer.

  The crosslinked or polymerized binder has a structure in which the main chain of the polymer is crosslinked or polymerized. Examples of the polymer main chain include polyolefin (saturated hydrocarbon), polyether, polyurea, polyurethane, polyester, polyamine, polyamide and melamine resin. A polyolefin main chain, a polyether main chain and a polyurea main chain are preferable, a polyolefin main chain and a polyether main chain are more preferable, and a polyolefin main chain is most preferable.

  The polyolefin main chain is composed of a saturated hydrocarbon. The polyolefin main chain is obtained, for example, by an addition polymerization reaction of an unsaturated polymerizable group. The polyether main chain has repeating units bonded by an ether bond (—O—). The polyether main chain is obtained, for example, by a ring-opening polymerization reaction of an epoxy group. In the polyurea main chain, repeating units are bonded by a urea bond (—NH—CO—NH—). The polyurea main chain is obtained, for example, by a condensation polymerization reaction between an isocyanate group and an amino group. The polyurethane main chain has repeating units bonded by urethane bonds (—NH—CO—O—). The polyurethane main chain is obtained, for example, by a polycondensation reaction between an isocyanate group and a hydroxyl group (including an N-methylol group). The polyester main chain has repeating units bonded by an ester bond (—CO—O—). The polyester main chain is obtained, for example, by a polycondensation reaction between a carboxyl group (including an acid halide group) and a hydroxyl group (including an N-methylol group). In the polyamine main chain, repeating units are bonded by an imino bond (—NH—). The polyamine main chain is obtained, for example, by a ring-opening polymerization reaction of an ethyleneimine group. The polyamide main chain has repeating units bonded by an amide bond (—NH—CO—). The polyamide main chain is obtained, for example, by a reaction between an isocyanate group and a carboxyl group (including an acid halide group). The melamine resin main chain is obtained, for example, by a polycondensation reaction between a triazine group (eg, melamine) and an aldehyde (eg, formaldehyde). In the melamine resin, the main chain itself has a crosslinked or polymerized structure.

The anionic group is preferably bonded to the main chain as a side chain of the binder via a linking group.
The linking group that binds the anionic group and the main chain of the binder is preferably a divalent group selected from —CO—, —O—, an alkylene group, an arylene group, and combinations thereof. The crosslinked or polymerized structure chemically bonds (preferably covalently bonds) two or more main chains. In the crosslinked or polymerized structure, it is preferable to covalently bond three or more main chains. The crosslinked or polymerized structure is preferably composed of a divalent or higher valent group selected from —CO—, —O—, —S—, a nitrogen atom, a phosphorus atom, an aliphatic residue, an aromatic residue, and combinations thereof. .

  The binder is preferably a copolymer having a repeating unit having an anionic group and a repeating unit having a crosslinked or polymerized structure. The proportion of the repeating unit having an anionic group in the copolymer is preferably 2 to 96 mol%, more preferably 4 to 94 mol%, and most preferably 6 to 92 mol%. The repeating unit may have two or more anionic groups. The proportion of the repeating unit having a crosslinked or polymerized structure in the copolymer is preferably 4 to 98 mol%, more preferably 6 to 96 mol%, and most preferably 8 to 94 mol%.

The repeating unit of the binder may have both an anionic group and a crosslinked or polymerized structure. The binder may contain other repeating units (repeating units having neither an anionic group nor a crosslinked or polymerized structure).
Other repeating units are preferably repeating units having a silanol group, an amino group or a quaternary ammonium group.

  In the repeating unit having a silanol group, the silanol group is directly bonded to the main chain of the binder or is bonded to the main chain via a linking group. The silanol group is preferably bonded to the main chain as a side chain via a linking group. The linking group that connects the silanol group and the main chain of the binder is preferably a divalent group selected from —CO—, —O—, an alkylene group, an arylene group, and combinations thereof. When the binder contains a repeating unit having a silanol group, the ratio is preferably 2 to 98 mol%, more preferably 4 to 96 mol%, and most preferably 6 to 94 mol%.

  In the repeating unit having an amino group or a quaternary ammonium group, the amino group or quaternary ammonium group is directly bonded to the main chain of the binder or bonded to the main chain via a linking group. The amino group or quaternary ammonium group is preferably bonded to the main chain as a side chain via a linking group. The amino group or quaternary ammonium group is preferably a secondary amino group, a tertiary amino group or a quaternary ammonium group, more preferably a tertiary amino group or a quaternary ammonium group. The group bonded to the nitrogen atom of the secondary amino group, tertiary amino group or quaternary ammonium group is preferably an alkyl group, preferably an alkyl group having 1 to 12 carbon atoms, Is more preferably an alkyl group of 1 to 6. The counter ion of the quaternary ammonium group is preferably a halide ion. The linking group that connects the amino group or the quaternary ammonium group to the main chain of the binder is a divalent group selected from —CO—, —NH—, —O—, an alkylene group, an arylene group, and combinations thereof. Preferably there is. When the binder includes a repeating unit having an amino group or a quaternary ammonium group, the ratio is preferably 0.1 to 32 mol%, more preferably 0.5 to 30 mol%, and more preferably 1 to 28 mol. % Is most preferred.

In addition, even if the silanol group, the amino group, and the quaternary ammonium group are contained in the repeating unit having an anionic group or the repeating unit having a crosslinked or polymerized structure, the same effect can be obtained.
The crosslinked or polymerized binder is preferably formed by applying a coating composition for forming a high refractive index layer on a transparent support and performing crosslinking or polymerization reaction simultaneously with or after coating.

  The binder of the high refractive index layer is added in an amount of 5 to 80% by mass based on the solid content of the coating composition of the layer.

The inorganic fine particles have a function of suppressing curing shrinkage as well as an effect of controlling the refractive index of the high refractive index layer.
In the high refractive index layer, the inorganic fine particles are preferably dispersed as finely as possible, and the mass average diameter is 1 to 200 nm. The mass average diameter of the inorganic fine particles in the high refractive index layer is preferably 5 to 150 nm, more preferably 10 to 100 nm, and most preferably 10 to 80 nm.
By refining the inorganic fine particles to 200 nm or less, a high refractive index layer that does not impair the transparency can be formed.

The content of the inorganic fine particles in the high refractive index layer is preferably 10 to 90% by mass, more preferably 15 to 80% by mass, and particularly preferably 15 to 75% by mass with respect to the mass of the high refractive index layer. . Two or more inorganic fine particles may be used in combination in the high refractive index layer.
When the low refractive index layer is provided on the high refractive index layer, the refractive index of the high refractive index layer is preferably higher than the refractive index of the transparent support.
The high refractive index layer contains an ionizing radiation curable compound containing an aromatic ring, an ionizing radiation curable compound containing a halogenated element other than fluorine (for example, Br, I, Cl, etc.), and atoms such as S, N, P, etc. A binder obtained by a crosslinking or polymerization reaction such as an ionizing radiation curable compound can also be preferably used.
In order to construct an antireflection film by constructing a low refractive index layer on a high refractive index layer, the refractive index of the high refractive index layer is preferably 1.55 to 2.40, more preferably 1 .60 to 2.20, more preferably 1.65 to 2.10, and most preferably 1.80 to 2.00.

In addition to the above components (inorganic fine particles, polymerization initiators, photosensitizers, etc.), the high refractive index layer includes resins, surfactants, antistatic agents, coupling agents, thickeners, anti-coloring agents, and coloring. Agents (pigments, dyes), antifoaming agents, leveling agents, flame retardants, ultraviolet absorbers, infrared absorbers, adhesion-imparting agents, polymerization inhibitors, antioxidants, surface modifiers, conductive metal particles, etc. It can also be added.
The film thickness of the high refractive index layer can be appropriately designed depending on the application. When using a high refractive index layer as an optical interference layer described later, the thickness is preferably 30 to 200 nm, more preferably 50 to 170 nm, and particularly preferably 60 to 150 nm.

The strength of the high refractive index layer is preferably H or higher, more preferably 2H or higher, and most preferably 3H or higher in a pencil hardness test according to JIS K5400.
Further, in the Taber test according to JIS K5400, the smaller the wear amount of the test piece before and after the test, the better.
The haze of the high refractive index layer is preferably as low as possible when it does not contain particles that impart an antiglare function. It is preferably 5% or less, more preferably 3% or less, and particularly preferably 1% or less.
The high refractive index layer is preferably constructed directly on the transparent support or via another layer.

In the present invention, the crosslinking reaction or polymerization reaction of the ionizing radiation curable compound is preferably performed in an atmosphere having an oxygen concentration of 10% by volume or less. This is not limited to the formation of the high refractive index layer but is common to the formation of the antiglare hard coat layer or the light diffusing layer.
By forming the high refractive index layer in an atmosphere having an oxygen concentration of 10% by volume or less, the physical strength, chemical resistance, and weather resistance of the high refractive index layer, and further, the high refractive index layer and the high refractive index layer are adjacent to each other. Adhesion with the layer can be improved.
Preferably, a high refractive index layer is formed by crosslinking or polymerization reaction of an ionizing radiation curable compound in an atmosphere having an oxygen concentration of 6% by volume or less, more preferably an oxygen concentration of 4% by volume or less, particularly preferably an oxygen concentration. Is 2% by volume or less, most preferably 1% by volume or less.
As a method of reducing the oxygen concentration to 10% by volume or less, it is preferable to replace the atmosphere (nitrogen concentration of about 79% by volume, oxygen concentration of about 21% by volume) with another gas, particularly preferably replacement with nitrogen (nitrogen purge). It is to be.

[Hard coat layer]
As the hard coat layer, a so-called smooth hard coat layer that is not anti-glare to impart physical strength to the antireflection film is preferably used, and is provided on the surface of the transparent support. In particular, the smooth hard coat layer is preferably provided between the transparent support and the antiglare hard coat layer, the transparent support and the light diffusion layer, and the transparent support and the high refractive index layer.
The hard coat layer is preferably formed by a crosslinking reaction or a polymerization reaction of an ionizing radiation curable compound. For example, it may be formed by applying a coating composition containing an ionizing radiation-curable polyfunctional monomer or polyfunctional oligomer on a transparent support and subjecting the polyfunctional monomer or polyfunctional oligomer to a crosslinking reaction or a polymerization reaction. it can.
The functional group of the ionizing radiation curable polyfunctional monomer or polyfunctional oligomer is preferably a light, electron beam, or radiation polymerizable group, and among them, a photopolymerizable functional group is preferable.
Examples of the photopolymerizable functional group include unsaturated polymerizable functional groups such as a (meth) acryloyl group, a vinyl group, a styryl group, and an allyl group. Among them, a (meth) acryloyl group is preferable. Specific examples of the ionizing radiation-curable polyfunctional monomer and polyfunctional oligomer are the same as those described for the antiglare hard coat layer.

  Specific examples of the photopolymerizable polyfunctional monomer having a photopolymerizable functional group include those exemplified for the high refractive index layer, and it is preferable to perform polymerization using a photopolymerization initiator and a photosensitizer. The photopolymerization reaction is preferably performed by ultraviolet irradiation after the hard coat layer is applied and dried.

  The binder of the hard coat layer is added in an amount of 30 to 95% by mass based on the solid content of the coating composition of the layer.

The hard coat layer preferably contains inorganic fine particles having an average primary particle size of 200 nm or less. The average particle diameter here is a mass average diameter. By setting the average particle size of the primary particles to 200 nm or less, a hard coat layer that does not impair the transparency can be formed.
The inorganic fine particles have functions of increasing the hardness of the hard coat layer and suppressing curing shrinkage of the coating layer. It is also added for the purpose of controlling the refractive index of the hard coat layer.
As inorganic fine particles, in addition to the inorganic fine particles exemplified in the high refractive index layer, silicon dioxide, aluminum oxide, calcium carbonate, barium sulfate, talc, kaolin, calcium sulfate, titanium dioxide, zirconium oxide, tin oxide, ITO, zinc oxide, etc. Fine particles. Preferred are silicon dioxide, titanium dioxide, zirconium oxide, aluminum oxide, tin oxide, ITO, and zinc oxide.

The preferable average particle diameter of the primary particles of the inorganic fine particles is 5 to 200 nm, more preferably 10 to 150 nm, still more preferably 20 to 100 nm, and particularly preferably 20 to 50 nm.
In the hard coat layer, the inorganic fine particles are preferably dispersed as finely as possible.
The particle size of the inorganic fine particles in the hard coat layer is preferably 5 to 300 nm, more preferably 10 to 200 nm, more preferably 20 to 150 nm, and particularly preferably 20 to 80 nm in terms of average particle diameter.

  The content of the inorganic fine particles in the hard coat layer is preferably 10 to 90% by mass, more preferably 15 to 80% by mass, and particularly preferably 15 to 75% by mass with respect to the total mass of the hard coat layer.

  The film thickness of the hard coat layer can be appropriately designed depending on the application. The film thickness of the hard coat layer is preferably 0.2 to 10 μm, more preferably 0.5 to 7 μm, and particularly preferably 0.7 to 5 μm.

The strength of the hard coat layer is preferably H or higher, more preferably 2H or higher, and most preferably 3H or higher in a pencil hardness test according to JIS K5400.
Further, in the Taber test according to JIS K5400, the smaller the wear amount of the test piece before and after the test, the better.
In the formation of the hard coat layer, when formed by a crosslinking reaction or a polymerization reaction of an ionizing radiation curable compound, the crosslinking reaction or the polymerization reaction is preferably performed in an atmosphere having an oxygen concentration of 10% by volume or less. . By forming in an atmosphere having an oxygen concentration of 10% by volume or less, a hard coat layer excellent in physical strength and chemical resistance can be formed.
Preferably, it is formed by a crosslinking reaction or polymerization reaction of an ionizing radiation curable compound in an atmosphere having an oxygen concentration of 6% by volume or less, more preferably an oxygen concentration of 4% by volume or less, particularly preferably an oxygen concentration of 2 Volume% or less, most preferably 1 volume% or less.

As a method of reducing the oxygen concentration to 10% by volume or less, it is preferable to replace the atmosphere (nitrogen concentration of about 79% by volume, oxygen concentration of about 21% by volume) with another gas, particularly preferably replacement with nitrogen (nitrogen purge). It is to be.
The hard coat layer is preferably formed by applying a coating composition for forming a hard coat layer on the surface of the transparent support.

[Low refractive index layer]
The low refractive index layer of the present invention will be described below.
The refractive index of the low refractive index layer of the antireflection film of the present invention is 1.20 to 1.49, preferably 1.30 to 1.44.

The material for forming the low refractive index layer of the present invention will be described below.
The low refractive index layer of the present invention preferably contains a fluorine-containing polymer as a low refractive index binder. The fluoropolymer is preferably a fluoropolymer that is crosslinked by heat or ionizing radiation having a coefficient of dynamic friction of 0.03 to 0.15 and a contact angle with water of 90 to 120 °. As described above, an inorganic filler for improving the film strength can also be used in the low refractive index layer of the present invention.

  Examples of the fluorine-containing polymer preferably used for the low refractive index layer include hydrolysis and dehydration condensates of perfluoroalkyl group-containing silane compounds (for example, (heptadecafluoro-1,1,2,2-tetrahydrodecyl) triethoxysilane). In addition, a fluorine-containing copolymer having a fluorine-containing monomer unit and a structural unit for imparting crosslinking reactivity as structural components may be mentioned.

  Specific examples of the fluorine-containing monomer unit include, for example, fluoroolefins (for example, fluoroethylene, vinylidene fluoride, tetrafluoroethylene, perfluorooctylethylene, hexafluoropropylene, perfluoro-2,2-dimethyl-1,3-dioxole. Etc.), partially (meth) acrylic acid or fully fluorinated alkyl ester derivatives (for example, Biscoat 6FM (manufactured by Osaka Organic Chemical), M-2020 (manufactured by Daikin), etc.), fully or partially fluorinated vinyl ethers, etc. However, perfluoroolefins are preferred, and hexafluoropropylene is particularly preferred from the viewpoints of refractive index, solubility, transparency, availability, and the like.

  As structural units for imparting crosslinking reactivity, structural units obtained by polymerization of monomers having a self-crosslinkable functional group in advance in the molecule such as glycidyl (meth) acrylate and glycidyl vinyl ether, carboxyl groups, hydroxy groups, amino groups Obtained by polymerization of a monomer having a sulfo group or the like (for example, (meth) acrylic acid, methylol (meth) acrylate, hydroxyalkyl (meth) acrylate, allyl acrylate, hydroxyethyl vinyl ether, hydroxybutyl vinyl ether, maleic acid, crotonic acid, etc.) And a structural unit obtained by introducing a crosslinking reactive group such as a (meth) acryloyl group into these structural units by a polymer reaction (for example, it can be introduced by a technique such as allowing acrylic acid chloride to act on a hydroxy group) And the like.

  In addition to the above-mentioned fluorine-containing monomer units and structural units for imparting crosslinking reactivity, monomers not containing fluorine atoms can be copolymerized as appropriate from the viewpoints of solubility in solvents and film transparency. There are no particular limitations on the monomer units that can be used in combination. For example, olefins (ethylene, propylene, isoprene, vinyl chloride, vinylidene chloride, etc.), acrylic esters (methyl acrylate, methyl acrylate, ethyl acrylate, acrylic acid 2) -Ethylhexyl), methacrylates (methyl methacrylate, ethyl methacrylate, butyl methacrylate, ethylene glycol dimethacrylate, etc.), styrene derivatives (styrene, divinylbenzene, vinyl toluene, α-methylstyrene, etc.), vinyl ethers (methyl) Vinyl ether, ethyl vinyl ether, cyclohexyl vinyl ether, etc.), vinyl esters (vinyl acetate, vinyl propionate, vinyl cinnamate etc.), acrylamides (N-tertbutylacrylamide, N-silane) B hexyl acrylamide), methacrylamides, and acrylonitrile derivatives.

  As described in JP-A-10-25388 and JP-A-10-147739, a curing agent may be appropriately used in combination with the above polymer.

  A particularly useful fluorine-containing polymer used in the low refractive index layer is a random copolymer of perfluoroolefin and vinyl ethers or vinyl esters. In particular, it preferably has a group capable of undergoing a crosslinking reaction alone (a radical reactive group such as a (meth) acryloyl group, a ring-opening polymerizable group such as an epoxy group or an oxetanyl group). These cross-linking reactive group-containing polymer units preferably occupy 5 to 70 mol%, particularly preferably 30 to 60 mol% of the total polymer units of the polymer.

As a preferable form of the copolymer used for the low refractive index layer, the one of the general formula 2 can be mentioned.
In General Formula 2, L represents a linking group having 1 to 10 carbon atoms, more preferably a linking group having 1 to 6 carbon atoms, particularly preferably a linking group having 2 to 4 carbon atoms, It may have a branched structure, may have a ring structure, and may have a heteroatom selected from O, N, and S.
Preferred _{examples, * - (CH 2) 2} -O - **, * - (CH 2) 2 -NH - **, * - (CH 2) 4 -O - **, * - (CH 2) _{6 -O - **, * - (} CH 2) 2 -O- (CH 2) 2 -O - **, * - CONH- (CH 2) 3 -O - **, * - CH 2 CH (OH ) CH ₂ —O — **, * —CH ₂ CH ₂ OCONH (CH ₂ ) ₃ —O — ** (* represents a linking site on the polymer main chain side, and ** represents a linking on the (meth) acryloyl group side) Represents a part). m represents 0 or 1;

  In general formula 2, X represents a hydrogen atom or a methyl group. From the viewpoint of curing reactivity, a hydrogen atom is more preferable.

  In General Formula 2, A represents a repeating unit derived from an arbitrary vinyl monomer, and is not particularly limited as long as it is a constituent component of a monomer copolymerizable with hexafluoropropylene. Tg (contributes to film hardness), solubility in solvents, transparency, slipperiness, dust / antifouling properties, etc., can be selected as appropriate, depending on the purpose, depending on the single or multiple vinyl monomers It may be configured.

Preferred examples include methyl vinyl ether, ethyl vinyl ether, t-butyl vinyl ether, cyclohexyl vinyl ether, isopropyl vinyl ether, hydroxyethyl vinyl ether, hydroxybutyl vinyl ether, glycidyl vinyl ether, vinyl ethers such as allyl vinyl ether, vinyl acetate, vinyl propionate, butyric acid. (Meth) such as vinyl esters such as vinyl, methyl (meth) acrylate, ethyl (meth) acrylate, hydroxyethyl (meth) acrylate, glycidyl methacrylate, allyl (meth) acrylate, (meth) acryloyloxypropyltrimethoxysilane Acrylates, styrene, styrene derivatives such as p-hydroxymethylstyrene, crotonic acid, maleic acid, itaconic acid Can be mentioned unsaturated carboxylic acids and derivatives thereof, more preferably ether derivatives, vinyl ester derivatives, particularly preferably a vinyl ether derivative.

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

  As a particularly preferred form of the copolymer used for the low refractive index layer, the general formula 8 can be mentioned.

  Formula 8

In general formula 8, X, x, and y have the same meaning as in general formula 2, and the preferred ranges are also the same.
n represents an integer of 2 ≦ n ≦ 10, preferably 2 ≦ n ≦ 6, and particularly preferably 2 ≦ n ≦ 4.
B represents a repeating unit derived from an arbitrary vinyl monomer, and may be composed of a single composition or a plurality of compositions. As an example, what was demonstrated as an example of A in the said General formula 2 is applicable.
z1 and z2 represent mol% of each repeating unit, and represent values satisfying 0 ≦ z1 ≦ 65 and 0 ≦ z2 ≦ 65. It is preferable that 0 ≦ z1 ≦ 30 and 0 ≦ z2 ≦ 10 respectively, and it is particularly preferable that 0 ≦ z1 ≦ 10 and 0 ≦ z2 ≦ 5.

  In the copolymer represented by the general formula 2 or 8, for example, a (meth) acryloyl group is introduced into a copolymer comprising a hexafluoropropylene component and a hydroxyalkyl vinyl ether component by any one of the methods described above. Can be synthesized.

  Although the preferable example of the copolymer useful by this invention is shown below, this invention is not limited to these.

  The copolymer used for the low refractive index layer is synthesized by synthesizing precursors such as a hydroxyl group-containing polymer by various polymerization methods such as solution polymerization, precipitation polymerization, suspension polymerization, precipitation polymerization, bulk polymerization, and emulsion polymerization. Then, it can be carried out by introducing a (meth) acryloyl group by the polymer reaction. The polymerization reaction can be performed by a known operation such as a batch system, a semi-continuous system, or a continuous system.

  The polymerization initiation method includes a method using a radical initiator, a method of irradiating light or radiation, and the like. These polymerization methods and polymerization initiation methods are, for example, the revised version of Tsuruta Junji “Polymer Synthesis Method” (published by Nikkan Kogyo Shimbun, 1971), Takatsu Otsu, Masato Kinoshita, “Experimental Methods for Polymer Synthesis” It is described in pp. 47-154 published in 1972.

Among the above polymerization methods, a solution polymerization method using a radical initiator is particularly preferable. Solvents used in the solution polymerization method are, for example, ethyl acetate, butyl acetate, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, tetrahydrofuran, dioxane, N, N-dimethylformamide, N, N-dimethylacetamide, benzene, toluene, acetonitrile, A single organic solvent such as methylene chloride, chloroform, dichloroethane, methanol, ethanol, 1-propanol, 2-propanol, and 1-butanol, or a mixture of two or more thereof may be used, or a mixed solvent with water may be used.

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

The reaction pressure can be selected as appropriate, but usually it is preferably about 1 to 100 kg / cm ² , particularly about 1 to 30 kg / cm ² . The reaction time is about 5 to 30 hours.

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

  The fluorine-containing polymer of the low refractive index layer is added in an amount of 20 to 95% by mass based on the solid content of the coating composition of the layer.

(Inorganic fine particles)
Next, the inorganic fine particles that can be contained in the low refractive index layer of the present invention are described below.
The amount of the inorganic fine particles is ^{preferably 1mg / m 2 ~100mg / m 2} , more preferably ^{5mg / m 2 ~80mg / m 2} , more preferably from ^{10mg / m 2 ~60mg / m 2} . When the blending amount is in the above range, the scratch resistance is excellent, the occurrence of fine irregularities on the surface of the low refractive index layer is reduced, and the appearance such as black tightening and the integrated reflectance are improved.
Since the inorganic fine particles are contained in the low refractive index layer, it is desirable that the inorganic fine particles have a low refractive index. Examples thereof include fine particles of magnesium fluoride and silica. In particular, silica fine particles are preferable in terms of refractive index, dispersion stability, and cost. The average particle diameter of the silica fine particles is preferably 30% to 150% of the thickness of the low refractive index layer, more preferably 35% to 80%, and still more preferably 40% to 60%. That is, when the thickness of the low refractive index layer is 100 nm, the particle diameter of the silica fine particles is preferably 30 nm to 150 nm, more preferably 35 nm to 80 nm, and still more preferably 40 nm to 60 nm.
If the particle size of the silica fine particles is in the above range, the effect of improving the scratch resistance is sufficient, and there is no occurrence of fine irregularities on the surface of the low refractive index layer. Reflectivity is improved.
The silica fine particles may be either crystalline or amorphous, and may be monodispersed particles or aggregated particles as long as a predetermined particle size is satisfied. The shape is most preferably a spherical diameter, but there is no problem even if the shape is indefinite.
Here, the average particle diameter of the inorganic fine particles is measured by a Coulter counter.

In order to further reduce the increase in the refractive index of the low refractive index layer, it is preferable to use hollow silica fine particles, and the hollow silica fine particles have a refractive index of 1.17 to 1.40, more preferably 1.17 to 1. .35, more preferably 1.17 to 1.30. The refractive index here represents the refractive index of the entire particle, and does not represent the refractive index of only the outer shell silica forming the hollow silica particles. At this time, when the radius of the void in the particle is a and the radius of the particle outer shell is b, the porosity x calculated from the following formula (XIV) is preferably 10 to 60%, more preferably 20 to 60. %, Most preferably 30-60%.
Formula (XIV): x = (4πa 3/3) / (4πb 3/3) × 100
If the hollow silica particles are made to have a lower refractive index and a higher porosity, the thickness of the outer shell becomes thinner and the strength of the particles becomes weaker. From the viewpoint of scratch resistance, the low refractive index is less than 1.17. Rate particles are not used.
The refractive index of these hollow silica particles was measured with an Abbe refractometer (manufactured by Atago Co., Ltd.).

In addition, at least one kind of silica fine particles having an average particle size of less than 25% of the thickness of the low refractive index layer (referred to as “silica fine particles having a small size”) is used as silica fine particles having the above particle size (“large size particles” It is preferably used in combination with “silica fine particles having a diameter”.
Since the fine silica particles having a small size can be present in the gaps between the fine silica particles having a large size, the fine particles can contribute as a retaining agent for the fine silica particles having a large size.
When the low refractive index layer is 100 nm, the average particle size of the silica fine particles having a small size is preferably from 1 nm to 20 nm, more preferably from 5 nm to 15 nm, and particularly preferably from 10 nm to 15 nm. Use of such silica fine particles is preferable in terms of raw material costs and a retaining agent effect.

Silica fine particles are treated by physical surface treatment such as plasma discharge treatment or corona discharge treatment in order to stabilize dispersion in the dispersion or coating solution, or to improve the affinity and binding to the binder component. Chemical surface treatment with a surfactant, a coupling agent, or the like may be performed. The use of a coupling agent is particularly preferred. As the coupling agent, an alkoxy metal compound (eg, titanium coupling agent, silane coupling agent) is preferably used. Of these, silane coupling treatment is particularly effective.
The above-mentioned coupling agent is used as a surface treatment agent for the inorganic filler of the low refractive index layer in advance for surface treatment prior to the preparation of the layer coating solution. It is preferable to make it contain in a layer.
The silica fine particles are preferably dispersed in the medium in advance before the surface treatment in order to reduce the load of the surface treatment.
What has been described above for silica fine particles also applies to other inorganic fine particles.

The low refractive index layer of the present invention preferably contains at least one of the hydrolyzate and partial condensate of the organosilane compound in order to achieve both antireflection performance and scratch resistance. The lower hard coat layer is also a sol It is particularly preferable to contain components.
The content of the organosilane sol component is preferably 0.1 to 50% by mass of the total solid content of the containing layer (addition layer) in the case of a surface layer such as a low refractive index layer which is a relatively thin film. 5-20 mass% is more preferable, and 1-10 mass% is the most preferable.

  In the low refractive index layer, the amount of the organosilane sol component used with respect to the fluorine-containing polymer is preferably from 5 to 100% by mass, and preferably from 5 to 40% by mass considering the effect, refractive index, film shape / surface shape, etc. % Is more preferable, 8-35 mass% is further more preferable, and 10-30 mass% is especially preferable.

  In the present invention, for the purpose of suppressing aggregation and sedimentation of the inorganic filler, it is also preferable to use a dispersion stabilizer in combination with the coating solution for forming each layer. As the dispersion stabilizer, polyvinyl alcohol, polyvinyl pyrrolidone, cellulose derivative, polyamide, phosphate ester, polyether, surfactant, silane coupling agent, titanium coupling agent and the like can be used. In particular, the above-mentioned silane coupling agent is preferable because the film after curing is strong.

  The composition for forming a low refractive index layer of the present invention is usually prepared in the form of a liquid, with the copolymer as a preferred constituent, and by dissolving various additives and a radical polymerization initiator in an appropriate solvent as necessary. Is done. At this time, the concentration of the solid content is appropriately selected according to the use, but is generally about 0.01 to 60% by mass, preferably 0.5 to 50% by mass, particularly preferably 1% to 20% by mass. %.

As described above, it is not always advantageous to add an additive such as a curing agent from the viewpoint of film hardness of the low refractive index layer, but from the viewpoint of interfacial adhesion with the high refractive index layer, etc. ) A curing agent such as an acrylate compound, polyfunctional epoxy compound, polyisocyanate compound, aminoplast, polybasic acid or anhydride thereof, or a small amount of inorganic fine particles such as silica can be added. When adding these, it is preferable that it is the range of 0-30 mass% with respect to the total solid of a low refractive index layer membrane | film | coat, It is more preferable that it is the range of 0-20 mass%, 0-10 mass % Range is particularly preferred.

  For the purpose of imparting properties such as antifouling properties, water resistance, chemical resistance, and slipping properties, known silicone-based or fluorine-based antifouling agents, slipping agents, and the like can be appropriately added. When these additives are added, it is preferably added in the range of 0.01 to 20% by mass of the total solid content of the low refractive index layer, more preferably in the range of 0.05 to 10% by mass. Particularly preferred is 0.1 to 5% by mass.

  Preferable examples of the silicone compound include those having a substituent at at least one of a terminal end and a side chain of a compound chain containing a plurality of dimethylsilyloxy units as repeating units. The compound chain containing dimethylsilyloxy as a repeating unit may contain a structural unit other than dimethylsilyloxy. The substituents may be the same or different, and a plurality of substituents are preferable. Examples of preferred substituents include acryloyl group, methacryloyl group, vinyl group, aryl group, cinnamoyl group, epoxy group, oxetanyl group, hydroxyl group, fluoroalkyl group, polyoxyalkylene group, carboxyl group, amino group and the like. It is done. Although there is no restriction | limiting in particular in molecular weight, It is preferable that it is 100,000 or less, It is especially preferable that it is 50,000 or less, It is most preferable that it is 3000-30000. Although there is no restriction | limiting in particular in silicone atom content of a silicone type compound, it is preferable that it is 18.0 mass% or more, it is especially preferable that it is 25.0-37.8 mass%, and 30.0-37.0. Most preferably, it is mass%. Examples of preferred silicone compounds are X-22-174DX, X-22-2426, X-22-164B, X22-164C, X-22-170DX, X-22-176D, X, manufactured by Shin-Etsu Chemical Co., Ltd. -22-1821 (above trade names), Chisso Corporation, FM-0725, FM-7725, DMS-U22, RMS-033, RMS-083, UMS-182 (above trade names) and the like. It is not limited to.

As the fluorine compound, a compound having a fluoroalkyl group is preferable. The fluoroalkyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, and a straight chain (for example, —CF ₂ CF ₃ , —CH ₂ (CF ₂ ) ₄ H, —CH ₂ (CF ₂ ) ₈ CF ₃ , —CH ₂ CH ₂ (CF ₂ ) ₄ H, etc.), even branched structures (eg, CH (CF ₃ ) ₂ , CH ₂ CF (CF ₃ ) ₂ , CH (CH ₃ ) CF ₂ CF ₃ , CH (CH ₃ ) (CF ₂ ) ₅ CF ₂ H, etc.), alicyclic structures (preferably 5-membered or 6-membered rings such as perfluorocyclohexyl group, perfluorocyclopentyl, etc. Group or an alkyl group substituted with these, and may have an ether bond (for example, CH ₂ OCH ₂ CF ₂ CF ₃ , CH ₂ CH ₂ OCH ₂ C ₄ F ₈ H, CH ₂ CH _{2 CH 2 CH 2 C 8 F 17} , CH 2 CH 2 OCF 2 CF 2 OCF 2 CF 2 H , etc.). A plurality of the fluoroalkyl groups may be contained in the same molecule.
It is preferable that the fluorine-based compound further has a substituent that contributes to bond formation or compatibility with the low refractive index layer film. The substituents may be the same or different, and a plurality of substituents are preferable. Examples of preferred substituents include acryloyl group, methacryloyl group, vinyl group, aryl group, cinnamoyl group, epoxy group, oxetanyl group, hydroxyl group, polyoxyalkylene group, carboxyl group, amino group and the like. The fluorine-based compound may be a copolymer or a copolymer oligomer with a compound not containing a fluorine atom, and the molecular weight is not particularly limited. Although there is no restriction | limiting in particular in fluorine atom content of a fluorine-type compound, It is preferable that it is 20 mass% or more, It is especially preferable that it is 30-70 mass%, It is most preferable that it is 40-70 mass%. Examples of preferred fluorine-based compounds include Daikin Chemical Industries, Ltd., R-2020, M-2020, R-3833, M-3833 (named above), Dainippon Ink Co., Ltd., Megafac F-171. , F-172, F-179A, and defender MCF-300 (named above), but are not limited thereto.

  For the purpose of imparting properties such as dust resistance and antistatic properties, a known cationic surfactant or a dustproof agent such as a polyoxyalkylene compound, an antistatic agent, or the like can be appropriately added. These dustproofing agent and antistatic agent may contain the structural unit as a part of the function in the above-mentioned silicone compound or fluorine compound. When these are added as additives, it is preferably added in the range of 0.01 to 20% by mass of the total solid content of the low refractive index layer, more preferably in the range of 0.05 to 10% by mass. Particularly preferred is 0.1 to 5% by mass. Examples of preferred compounds include, but are not limited to, Dainippon Ink Co., Ltd., MegaFace F-150 (trade name), Toray Dow Corning Co., Ltd., SH-3748 (trade name), and the like. Do not mean.

  The various coating liquids of the present invention are preferably subjected to filtration treatment of the coating liquid. For this filtration treatment, various commonly known filters can be used. Specifically, polypropylene, polyester, nylon, polytetrafluoroethylene, polyvinylidene fluoride, polysulfone, glass fiber, stainless steel mesh, etc. are raised as the filter medium. In particular, polypropylene, polyester, nylon, polytetrafluoroethylene and the like are preferable as the organic solvent-based treatment. These filters are usually provided commercially as cartridge type filters. As the filter material of the filter, it is filtered in the thickness direction with a sheet type filter material of the surface type that filters on the surface and a thick filter material made by knitting fibers and heat-sealing. There is a depth type filter medium, and a depth type filter having a large surface area of the filter medium is preferable. Of the depth type filters, filters provided as a type capable of high-precision filtration by each filter manufacturer are particularly preferable.

  Of these, polypropylene filters are often used for the antiglare hard coat layer, light scattering layer, hard coat layer, and the like. For the low refractive index layer, a polypropylene filter or a tetrafluoroethylene filter is often used. The filtration pore diameter of these filters is generally indicated by nominal filtration accuracy or absolute filtration accuracy, but those of about 0.5 μm to 200 μm are known. Since there are many coating liquids containing particles for the coating liquid of the present invention, an optimum pore diameter can be selected and used in accordance with the permeability of the particles.

[Method for producing optical film]
The optical film of the present invention can be formed by the following method, but is not limited to this method.
First, a coating solution containing components for forming each layer is prepared. Next, a coating solution for forming a hard coat layer is prepared by using a dip coating method, an air knife coating method, a curtain coating method, a roller coating method, a die coating method, a wire bar coating method, a gravure coating method, an extrusion coating method (USA) (See Japanese Patent No. 2681294), it can be coated on a transparent support, heated and dried. Among these coating methods, it is preferable to apply the gravure coating method because a coating solution with a small coating amount such as each layer of the antireflection film can be applied with high film thickness uniformity. Among the gravure coating methods, the micro gravure method has a high film thickness uniformity and is more preferable.
In addition, a coating solution with a small coating amount can be applied with high film thickness uniformity even by using a die coating method. Further, since the die coating method is a pre-measuring method, film thickness control is relatively easy, and the solvent in the coating part Is preferred because of less transpiration. Two or more layers may be applied simultaneously. The methods for simultaneous application are described in US Pat. Nos. 2,761,791, 2,941,898, 3,508,947, and 3,526,528 and Yuji Harasaki, Coating Engineering, page 253, Asakura Shoten (1973). Thereafter, the monomer for forming the antiglare hard coat layer is polymerized and cured by light irradiation or heating. Thereby, a hard coat layer is formed.
Here, if necessary, a plurality of hard coat layers can be formed, and smooth hard coat layer application and curing can be performed by the same method before application of the antiglare hard coat layer.
Next, a coating solution for forming a low refractive index layer is applied onto the hard coat layer in the same manner, and light irradiation or heating is performed to form the low refractive index layer. In this way, the antireflection film of the present invention is obtained.

  The micro gravure coating method used in the present invention is a gravure roll having a diameter of about 10 to 100 mm, preferably about 20 to 50 mm and engraved with a gravure pattern on the entire circumference, below the support and in the transport direction of the support. The gravure roll is rotated in reverse with respect to the gravure roll, the excess coating liquid is scraped off from the surface of the gravure roll by a doctor blade, and a fixed amount of the coating liquid is removed from the support in a position where the upper surface of the support is in a free state. The coating method is characterized in that the coating liquid is transferred onto the lower surface for coating. A roll-shaped transparent support is continuously unwound, and at least one layer of at least one of a hard coat layer or a low refractive index layer containing a fluorine-containing polymer is provided on one side of the unwound support. Can be applied by.

As coating conditions by the micro gravure coating method, the number of gravure patterns imprinted on the gravure roll is preferably 50 to 800 lines / inch, more preferably 100 to 300 lines / inch, and the depth of the gravure pattern is 1 to 600 μm. Is preferable, 5 to 200 μm is more preferable, the rotation speed of the gravure roll is preferably 3 to 800 rpm, more preferably 5 to 200 rpm, and the conveyance speed of the support is 0.5 to 100 m / min. It is preferably 1 to 50 m / min.
The antireflection film of the present invention thus formed has a haze value of 3 to 70%, preferably 4 to 60%, and an average reflectance of 450 nm to 650 nm is preferably 3.0% or less, preferably Is 2.5% or less.
When the antireflection film of the present invention has a haze value and an average reflectance in the above range, good antiglare properties and antireflection properties can be obtained without causing deterioration of the transmitted image.

  When the antireflection film of the present invention is used in a liquid crystal display device, it is disposed on the outermost surface of the display by providing an adhesive layer on one side. When the transparent support is triacetylcellulose, triacetylcellulose is used as a protective film for protecting the polarizing layer of the polarizing plate. Therefore, it is preferable in terms of cost to use the antireflection film of the present invention as it is for the protective film.

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

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

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

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

The method for stretching the polymer film is described in detail in paragraph numbers [0020 to 0030] of JP-A-2002-86554.
Of the two protective films of the polarizer, the film other than the antireflection film is preferably an optical compensation film having an optical compensation layer comprising an optically anisotropic layer. The optical compensation film (retardation film) can improve the viewing angle characteristics of the liquid crystal display screen.
A known film can be used as the optical compensation film, but the optical compensation film described in JP-A-2001-100042 is preferable in terms of widening the viewing angle.

Of the two protective films of the polarizer, it is preferable that the transparent support of at least one protective film satisfies the following formulas (I) and (II) because the display improvement effect from the oblique direction of the liquid crystal display screen is high. In particular, it is particularly preferable that the transparent support of the present invention satisfies the following formulas (I) and (II).
(I): 0 ≦ Re (630) ≦ 10 and | Rth (630) | ≦ 25
(II): | Re (400) −Re (700) | ≦ 10 and | Rth (400) −Rth (700) | ≦ 35

  The antireflection film of the present invention can be applied to an image display device such as a liquid crystal display device (LCD), a plasma display panel (PDP), an electroluminescence display (ELD), or a cathode ray tube display device (CRT). Since the antireflection film of the present invention has a transparent support, the transparent support side is adhered to the image display surface of the image display device.

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

  The VA mode liquid crystal cell includes (1) a narrowly defined VA mode liquid crystal cell in which rod-like liquid crystalline molecules are aligned substantially vertically when no voltage is applied, and substantially horizontally when a voltage is applied (Japanese Patent Laid-Open No. Hei 2-). 176625 (in Japanese Patent Publication No. 176625), and (2) a liquid crystal cell (SID97, Digest of tech. Papers (Proceedings) 28 (1997) 845 in which the VA mode is converted into a multi-domain (for MVA mode) in order to enlarge the viewing angle. ), (3) A liquid crystal cell in a mode (n-ASM mode) in which rod-like liquid crystalline molecules are substantially vertically aligned when no voltage is applied and twisted multi-domain alignment is applied when a voltage is applied (Preliminary collections 58-59 of the Japan Liquid Crystal Society) (1998)), and (4) SURVAIVAL mode liquid crystal cells (announced at LCD International 98).

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

Furthermore, as a whole including a bend alignment mode liquid crystal cell and a polarizing plate including an optically anisotropic layer, it has optical characteristics satisfying the following mathematical formula (XV) in all measurements at wavelengths of 450 nm, 550 nm and 630 nm. It is preferable that the effect of improving the display from the oblique direction of the liquid crystal display screen is high, and it is particularly preferable that the polarizing plate using the optical film of the present invention as a protective film satisfies the following formula (XV).
Formula (XV): 0.05 <(Δn × d) / (Re × Rth) <0.20
[In formula (XV), Δn is the intrinsic birefringence of the rod-like liquid crystalline molecule in the liquid crystal cell; d is the thickness of the liquid crystal layer of the liquid crystal cell in nm; Re is the entire optical anisotropic layer] Rth is the retardation value in the thickness direction of the entire optically anisotropic layer. ]

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

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

  Hereinafter, the present invention will be specifically described in detail based on examples, but the present invention is not limited thereto.

[Example 1]
<Production of support>
(1) Preparation of cellulose acylate solution (a) A cellulose acylate solution (a) having the following composition was prepared.
[Composition]: Cellulose acylate solution (a)
Cellulose triacetate A (substitution degree 2.84, viscosity average polymerization degree 306, water content 0.2 mass%, viscosity 6 mass% in dichloromethane solution 315 mPa · s, average particle diameter 1.5 mm with standard deviation 0.5 mm 100 parts by weight Methylene chloride (first solvent) 320 parts by weight Methanol (second solvent) 83 parts by weight 1-butanol (third solvent) 3 parts by weight Plasticizer A (triphenyl phosphate) 7.6 Part by mass Plasticizer B (biphenyldiphenyl phosphate) 3.8 parts by mass UV agent a: 2 (2′-hydroxy-3 ′, 5′-di-tert-butylphenyl) benzotriazole 0.7 part by mass UV agent b : 2 (2′-hydroxy-3 ′, 5′-di-tert-amylphenyl) -5-chlorobenzotriazole 0.3 part by mass Citric acid ester mixed Things (citric acid, monoethyl ester, diethyl ester, triethyl ester mixture) 0.006 parts by weight fine particles (silicon dioxide (particle size 15 nm), Mohs hardness: about 7) 0.05 parts by weight

[Cotton compound: Cellulose acetate A is as follows]
The cellulose triacetate A used here has a residual acetic acid content of 0.1% by mass or less, a Ca content of 58 ppm, a Mg content of 42 ppm, a Fe content of 0.5 ppm, free acetic acid 40 ppm, and sulfuric acid. The ions contained 15 ppm. The degree of substitution of the 6-position acetyl group was 0.91, 32.5% of the total acetyl. The acetone extract was 8% by mass, and the weight average molecular weight / number average molecular weight ratio was 2.5. The yellow index is 1.7, the haze is 0.08, the transparency is 93.5%, the Tg (glass transition temperature; measured by DSC) is 160 ° C., and the crystallization heat generation is 6.4 J / g. Met. Cellulose triacetate A was synthesized from cellulose collected from cotton as a raw material. In the following description, this is called cotton raw material TAC.

[Adjustment of cellulose acylate solution dope]
(Dope dissolution / filtration)
A cellulose triacetate powder (flakes) is gradually added to a 4000 L stainless steel dissolution tank having stirring blades while mixing and mixing well with a plurality of solvents, so that the whole becomes 2000 kg. Prepared. In addition, all the solvents used that the water content is 0.5 mass% or less. First, a powder of cellulose triacetate is charged into a dispersion tank, and a stirring shear rate is initially 5 m / sec (shear stress 5 × 10 ⁴ kgf / m / sec ² ). The mixture was dispersed for 30 minutes under the condition of having a core stirring shaft and an anchor blade on the central shaft and stirring at a peripheral speed of 1 m / sec (shear stress 1 × 10 ⁴ kgf / m / sec ² ). The starting temperature of dispersion was 25 ° C., and the final temperature reached 48 ° C. After completion of the dispersion, the high-speed stirring was stopped, and the peripheral speed of the anchor blade was set to 0.5 m / sec and further stirred for 100 minutes to swell the cellulose triacetate flakes. Until the end of swelling, the inside of the tank was pressurized to 0.12 MPa with nitrogen gas. At this time, the oxygen concentration in the tank was less than 2 vol%, and the state of no problem was maintained in terms of explosion protection. The water content in the dope was confirmed to be 0.5% by mass or less, and 0.3% by mass in this experiment.

The above swollen solution was heated from a tank to 50 ° C. with a jacketed pipe, and further heated to 90 ° C. under a pressure of 2 MPa to be completely dissolved. The heating time was 15 minutes.
Next, the temperature was lowered to 36 ° C., and a dope was obtained by passing through a filter medium having a nominal pore diameter of 8 μm. At this time, the primary pressure of filtration was 1.5 MPa, and the secondary pressure was 1.2 MPa. Filters, housings, and pipes that are exposed to high temperatures were made of Hastelloy alloy and had excellent corrosion resistance, and those having a jacket for circulating a heat medium for heat insulation and heating were used.

(Concentration, filtration, de-method, additive)
The pre-concentration dope thus obtained was flushed at 80 ° C. in a normal pressure tank, and the evaporated solvent was recovered and separated by a condenser. The solid concentration of the dope after flashing was 21.8% by mass. The flash tank had an anchor blade on the central axis, and deaerated by stirring at a peripheral speed of 0.5 m / sec. The temperature of the dope in the tank was 25 ° C., and the average residence time in the tank was 50 minutes. The shear viscosity measured at 25 ° C. after collecting this dope was 450 (Pa · s) at a shear rate of 10 (sec ⁻¹ ).

  Next, the dope was defoamed by irradiating weak ultrasonic waves. Thereafter, under a pressure of 1.5 MPa, a sintered fiber metal filter having a nominal pore diameter of 10 μm was first passed, and then a 10 μm sintered fiber filter was also passed. The primary pressures were 1.5 and 1.2 MPa, and the secondary pressures were 1.0 and 0.8 MPa. The dope temperature after filtration was adjusted to 36 ° C. and stored in a 2000 L stainless steel stock tank. The stock tank had an anchor blade on the central axis and was constantly stirred at a peripheral speed of 0.3 m / sec. Thus, a cellulose acylate dope (a) was prepared.

(2-1) Solution casting method (band method)
After performing the above-mentioned step of preparing the cellulose acylate solution, the obtained dope was cast using a band casting machine, and a step of forming a cellulose acylate film from the cellulose acylate solution was performed. .
As the metal support (casting band), an endless band made of stainless steel, having a width of 2 m, a length of 56 m (area 112 m ² ), and a band thickness of 1.5 mm was used. The arithmetic average roughness (Ra) of the metal support was 0.006 μm, the maximum height (Ry) was 0.06 μm, and the ten-point average roughness (Rz) was 0.009 μm. The arithmetic average roughness (Ra), maximum height (Ry), and ten-point average roughness (Rz) were measured according to JIS B 0601. The band uses a type driven by two drums, and the tension of the band at that time is adjusted to 1.5 × 10 ⁴ kg / m, and the relative speed difference between the band and the drum becomes 0.01 m / min or less. It was a thing. The band drive speed fluctuation was 0.5% or less.

  As the casting drum, one having a facility for circulating a heat transfer medium (refrigerant) inside to cool the support was used. Further, since the other drum supplies heat for drying, the heat transfer medium can pass water. The temperature of each heat transfer medium was 5 ° C. (casting die side) and 40 ° C. The surface temperature of the central part of the support just before casting was 15 ° C. The temperature difference between both ends was 6 ° C. or less.

There should be no surface defects in either the drum or the band, there are no pinholes of 30 μm or more, 1 pinhole of 10 μm to 30 μm / m2 or less, and ² pinholes of 10 μm or less A support that is less than / m ² was used.

  Three layers of the dope were co-cast from the casting die on this support. The co-casting was finished thickness, 4 μm, 73 μm, 3 μm from the air surface, and the casting width was 1700 mm so that the product thickness was 80 μm, and the dope flow rate from the casting die was adjusted.

(Casting drying)
The temperature of the casting chamber provided with the casting die and the support was kept at 35 ° C.
The dope cast on the band was first dried by sending parallel-flow drying air. The overall heat transfer coefficient from the drying air to the dope during drying was 24 kcal / m ² · hr · ° C. The temperature of the drying air was 135 ° C on the upstream side of the upper part of the band, and 140 ° C on the downstream side. The lower part of the band was set to 65 ° C. The saturation temperature of each gas was around -8 ° C. The oxygen concentration in the dry atmosphere on the support was kept at 5 vol%. Note that the air was replaced with nitrogen gas in order to maintain the oxygen concentration at 5 vol%.

  For 5 seconds after casting, the static pressure fluctuation in the immediate vicinity of the casting die was suppressed to ± 1 Pa or less so that the dry wind did not directly hit the dope with a wind shield. When the solvent ratio in the dope reached 50% by mass on a dry basis, the film was peeled off from the casting support. The surface temperature of the peeled film was 15 ° C. The drying rate on the support was an average of 60% by weight dry weight reference solvent / min.

(2-2) Solution casting method (drum method)
As a process of casting the cellulose acylate solution described above and forming a cellulose acylate film from the cellulose acylate solution, a method of performing a metal support with a drum was also carried out.
A stainless steel drum having a width of 2.5 m was used as a support. And what grind | polished so that the surface roughness might be 0.05 micrometer or less was used. The material was made of SUS316 and had sufficient corrosion resistance and strength. The overall thickness unevenness of the drum was 0.5% or less. Rotation unevenness was rotated with an accuracy of 0.2 mm or less. Also in the drum, the average roughness of the surface is 0.01 μm or less, and it has sufficient hardness and durability by the chrome plating treatment. The position fluctuation in the vertical direction accompanying the drum rotation on the surface of the support just below the casting die was set to 200 μm or less. The support is installed in a casing having wind pressure vibration suppression means. Three layers of dope were co-cast from this die on this support. Rotation unevenness was rotated with an accuracy of 0.2 mm or less. Also in the drum, the average roughness of the surface is 0.01 μm or less, and it has sufficient hardness and durability by the chrome plating treatment.

  The surface temperature of the central part of the support just before casting was −5 ° C. The temperature difference between both ends was 2 ° C. or less.

There should be no surface defects in either the drum or the band, there are no pinholes of 30 μm or more, 1 pinhole of 10 μm to 30 μm / m2 or less, and ² pinholes of 10 μm or less A support that is less than / m ² was used.

(Casting drying)
The temperature of the casting chamber provided with the casting die and the support was kept at 25 ° C. The dope cast on the band was first dried by sending parallel-flow drying air. The overall heat transfer coefficient from the drying air to the dope during drying was 24 kcal / m ₂ · hr · ° C. The temperature of the drying air was 40 ° C. The saturation temperature of each gas was around -8 ° C. The oxygen concentration in the dry atmosphere on the support was kept at 5 vol%. Note that the air was replaced with nitrogen gas in order to maintain the oxygen concentration at 5 vol%.

  After casting, when the solvent ratio in the dope was 300% by mass or less on a dry basis, the film was peeled off from the casting support. The peeling tension at this time was 10 kgf / m, and the peeling speed (peeling roll draw) with respect to the support speed was set to be appropriately peeled in the range of 100.1% to 110%. The surface temperature of the peeled film was 15 ° C. The drying rate on the support was an average of 60% by weight dry weight reference solvent / min.

  After casting by the above band or drum method, the peeled film was conveyed by a transfer section provided with a number of rollers. The transition part was provided with three rollers, and the temperature of the transition part was kept at 40 ° C. During conveyance with the roller at the crossing portion, a tension of 16N to 160N was applied to the film.

(3) Tenter transport, drying, and ear cutting The film peeled off was transported through the drying zone of the tenter while being fixed at both ends with a tenter having a clip, and dried with drying air. Further, the interior of the tenter was divided into three zones, and the drying air temperature in each zone was set to 90 ° C., 100 ° C., and 110 ° C. from the upstream side. The gas composition of the drying air was set to a saturated gas concentration of −10 ° C. The average drying rate in the tenter was 120% by mass (dry weight reference solvent) / min. Conditions were adjusted so that the amount of residual solvent in the film was 7 to 10% by mass or less at the exit of the tenter. In the tenter, the film was stretched in the width direction while being conveyed. The amount of widening when the width when conveyed to the tenter was 100% was 103%. The stretching ratio (tenter driving draw) from the peeling roller to the tenter inlet was 102%. As for the stretching ratio in the tenter, the difference in the substantial stretching ratio at a portion 10 mm or more away from the tenter biting portion was 10% or less, and the difference in the stretching ratio at any two points 20 mm apart was 5% or less. The ratio of the length of the base end fixed by the tenter was 90%. Further, the tenter clip was transported while being cooled so as not to exceed 50 ° C.

  Then, the ears were cut at both ends within 30 seconds from the tenter exit. Ears 50 mm on both sides were cut with an NT type cutter. The oxygen concentration in the dry atmosphere of the tenter part was kept at 5 vol%. Note that the air was replaced with nitrogen gas in order to maintain the oxygen concentration at 5 vol%. The film was preheated in a predrying zone supplied with 100 ° C. drying air before being dried at a high temperature in a roller conveyance zone described later. At this time, the amount of residual solvent in the film was approximately 5% by mass.

(4) Post-drying The cellulose triacetate film after trimming obtained by the above method was dried at high temperature in the roller transport zone. The roller conveyance zone was divided into four sections, and dry air of 130 ° C, 130 ° C, 130 ° C, and 130 ° C was supplied from the upstream side. At this time, the roller conveying tension of the film was 100 N / width, and the film was dried for about 7 minutes until the residual solvent amount finally reached 0.3% by mass. Thus, a cellulose acylate film (length 3500 m, width 1300 mm, average thickness 80 μm) as a transparent support was produced.
The thickness of the film is measured using a contact-type film thickness meter (manufactured by Anritsu), and in order to investigate the thickness unevenness of the film, sampling of the above measurement is performed at 5 points at equal intervals in the width direction 1 m and at 1 m in the longitudinal direction. A total of 25 points of 5 points were taken at equal intervals, and each was measured.
The curl value in the width direction of Example Sample 1 of the cellulose acylate film produced as described above was −4.5 / m.

(5) Evaluation of cellulose acylate film (Measurement of plasticizer amount)
The surface plasticizer amount of the film was measured by ATR-IR using a Nicolet FT-IR apparatus Magma 760. The measurement conditions were KRS-5 as a reflection measurement crystal and an incident angle of 45 degrees. Measurement of amount of plasticizer is a plasticizer absorption peak (1390 cm ^-1), the intensity of the absorption peak (1470 cm ^-1) of the cellulose acylate was measured, it was performed by a method for determining the intensity ratio. The plasticizer content was determined by a calibration curve using samples with different plasticizer / cellulose acylate ratios.
Moreover, the plasticizer amount of the whole film was calculated | required by the transmission IR measurement of a film thickness direction with the same measuring method.
In addition, in order to examine the plasticizer amount distribution of the film, the sampling of the above measurement was performed at a total of 25 points of 5 points at equal intervals in the width direction 1 m and 5 points at equal intervals in the longitudinal direction 1 m. went.
(Flexibility of film)
The flexibility of the film was determined comprehensively from the handleability, workability, tear strength, etc. of the resulting film.
A: Soft B: Slightly soft C: Good flexibility D: Slightly hard and brittle
E: Hard and brittle.

(6) Cellulose Acylate Film Evaluation Results As shown in Table 1, Example Samples were changed in the same manner as described above except that the amount of plasticizer in the cellulose acylate solution, casting method, post-drying conditions, etc. were changed. 1 to 13 and Comparative Samples 1 to 3 were prepared. The comparative sample 3 is the same as the sample 1 except that it was prepared by changing the conveying speed of the support to double speed. Among them, the support surface is a surface that is in contact with the metal support during casting, and the air surface is a surface opposite to the metal support.
As a result, it was possible to change the surface amount of the plasticizer by changing the amount of the plasticizer being charged. At this time, when the amount of the plasticizer was 0%, the amount of the surface plasticizer could be 0%. At this time, the film had poor flexibility and was not suitable for the support of the present invention. Also, as a casting method, drum casting with a short peeling time from the metal support during casting can reduce the amount of plasticizer on the side of the support having good flatness. Further, the amount of the plasticizer on the surface can be reduced by the samples 10 and 11 in which the post-drying layer conditions are increased as compared with the plasticizer amount of the entire film.
Sample 3, sample 4, and sample 5 shall be read as “reference example” instead of “example”.

(7) Preparation and evaluation of inventive samples 51 to 66 and comparative samples 51 to 54 of the antireflection film applied on the cellulose acylate film

(Synthesis of perfluoroolefin copolymer (1))

Into a stainless steel autoclave with a stirrer of 100 ml, 40 ml of ethyl acetate, 14.7 g of hydroxyethyl vinyl ether and 0.55 g of dilauroyl peroxide were charged, and the inside of the system was deaerated and replaced with nitrogen gas. Furthermore, 25 g of hexafluoropropylene (HFP) was introduced into the autoclave and the temperature was raised to 65 ° C. The pressure when the temperature in the autoclave reached 65 ° C. was 5.4 kg / cm ² . The reaction was continued for 8 hours while maintaining the temperature, and when the pressure reached 3.2 kg / cm ² , the heating was stopped and the mixture was allowed to cool. When the internal temperature dropped to room temperature, unreacted monomers were driven out, the autoclave was opened, and the reaction solution was taken out. The obtained reaction solution was poured into a large excess of hexane, and the polymer was precipitated by removing the solvent by decantation. Further, this polymer was dissolved in a small amount of ethyl acetate and reprecipitated twice from hexane to completely remove the residual monomer. After drying, 28 g of polymer was obtained. Next, 20 g of the polymer was dissolved in 100 ml of N, N-dimethylacetamide, and 11.4 g of acrylic acid chloride was added dropwise under ice cooling, followed by stirring at room temperature for 10 hours. Ethyl acetate was added to the reaction solution, washed with water, the organic layer was extracted and concentrated, and the resulting polymer was reprecipitated with hexane to obtain 19 g of perfluoroolefin copolymer (1). The resulting polymer had a refractive index of 1.421.

(Synthesis of fluororesin-containing polymer (FP-8))
To a reactor equipped with a stirrer and a reflux condenser, 39.93 g of 1H, 1H, 7H-dodecafluoroheptyl acrylate, 1.1 g of dimethyl 2,2′-azobisisobutyrate and 30 g of 2-butanone were added, and a nitrogen atmosphere was added. For 6 hours at 78 ° C. to complete the reaction. The mass average molecular weight was 2.9 × 10 ⁴ .

(Preparation of sol liquid a-1)
A stirrer, a reactor equipped with a reflux condenser, 120 parts of methyl ethyl ketone, 100 parts of acryloyloxypropyltrimethoxysilane (KBM-5103, manufactured by Shin-Etsu Chemical Co., Ltd.), 3 parts of diisopropoxyaluminum ethyl acetoacetate were added and mixed. Thereafter, 30 parts of ion-exchanged water was added and reacted at 60 ° C. for 4 hours, and then cooled to room temperature to obtain sol liquid a-1. The mass average molecular weight was 1600, and among the components higher than the oligomer component, the component having a molecular weight of 1000 to 20000 was 100%. ^The condensation rate α according to the above formula (IX) calculated from ²⁹ Si-NMR measurement was 0.88. Further, from the gas chromatography analysis, the raw material acryloyloxypropyltrimethoxysilane did not remain at all.

(Preparation of sol liquid a-2)
In a reactor equipped with a stirrer and a reflux condenser, 70 parts of acryloxypropyltrimethoxysilane, 30 parts of methyltrimethoxysilane (KBM-13, manufactured by Shin-Etsu Chemical Co., Ltd.), 3 parts of diisopropoxyaluminum ethyl acetoacetate After adding and mixing, 3 parts of ion-exchanged water was added and reacted at 40 ° C. for 30 minutes to obtain sol solution a-2. The mass average molecular weight was 800, and among the components higher than the oligomer component, the component having a molecular weight of 1000 to 20000 was 30%. ^The condensation rate α determined by ²⁹ Si-NMR was 0.56. From the gas chromatography analysis, the raw materials acryloxypropyltrimethoxysilane and methyltrimethoxysilane had a residual ratio of 10% or less.

(Preparation of sol liquid b)
After the reaction, after cooling to room temperature, a sol solution b was obtained in the same manner as the sol composition a-1 except that 6 parts of acetylacetone was added.

(Composition of coating liquid A-1 for antiglare hard coat layer)
PET-30 50.0g
Irgacure 184 2.0g
SX-350 (30%) 1.7 g
Cross-linked acrylic-styrene particles (30%) 13.3 g
FP-8 0.75g
KBM-5103 10.0g
Toluene 38.5g

  The coating solution was filtered through a polypropylene filter having a pore size of 30 μm to prepare a coating solution A-1 for an antiglare hard coat layer.

(Composition of coating liquid A-2 for antiglare hard coat layer)
The antiglare property is exactly the same as the coating solution A-1, except that 10.0 g of KBM-5103 in the coating solution A-1 for antiglare hard coat layer is changed to 10.0 g of sol solution a-2. Hard coat layer coating solution A-2 was prepared.

(Composition of coating liquid A-3 for antiglare hard coat layer)
PET-30 42.3g
Irgacure 184 2.0g
SX-350 (30%) 23.3 g
Cross-linked acrylic-styrene particles (30%) 7.5g
FP-8 0.07g
KBM-5103 9.3g
Toluene 86.1g

(Composition of coating solution A-4 for antiglare hard coat layer)
PET-30 42.4g
Irgacure 184 1.6g
SX-350 (30%) 23.8 g
Cross-linked acrylic-styrene particles (30%) 3.8 g
FP-8 0.1g
X-40-2671G 10.5g
Toluene 76.9g

  The coating liquid was filtered through a polypropylene filter having a pore diameter of 30 μm to prepare antiglare hard coat layer coating liquids A-3 and A-4.

(Composition of coating liquid B-1 for light diffusion layer)
Desolite Z7404 285g
DPHA 85g
KBM-5103 28g
KE-P150 (30%) 90g
MXS-300 (30%) 35g
FP-8 0.12g
MEK 17g
MIBK 60g

  The coating liquid was filtered through a polypropylene filter having a pore diameter of 30 μm to prepare a light diffusion layer coating liquid B-1.

(Composition of coating liquid B-2 for light diffusion layer)
Except for changing 28 g of KBM-5103 of the light diffusion layer coating liquid B-1 to 28.0 g of the sol liquid a-2, the light diffusion layer coating liquid B- was exactly the same as the coating liquid B-1. 2 was adjusted.

(Composition of coating liquid B-3 for light diffusion layer)
Except for changing 28 g of KBM-5103 of the light diffusion layer coating liquid B-1 to 28.0 g of X-40-2671G, the coating liquid B- for light diffusion layer was exactly the same as the coating liquid B-1. 3 was adjusted.

  The compounds used are shown below.

PET-30: A mixture of pentaerythritol triacrylate and pentaerythritol tetraacrylate [manufactured by Nippon Kayaku Co., Ltd.]
・ Irgacure 184: Polymerization initiator [Ciba Specialty Chemicals Co., Ltd.]
SX-350: Average particle size 3.5 μm Cross-linked polystyrene particles [refractive index 1.60, manufactured by Soken Chemical Co., Ltd., 30% toluene dispersion, used after dispersion at 10,000 rpm in a Polytron disperser for 20 minutes]
Crosslinked acrylic-styrene particles: average particle size 3.5 μm [refractive index 1.55, manufactured by Soken Chemical Co., Ltd., 30% toluene dispersion, used after dispersion for 20 minutes at 10,000 rpm with a Polytron disperser]
KBM-5103: Silane coupling agent (acryloxypropyltrimethoxysilane) [manufactured by Shin-Etsu Chemical Co., Ltd.]
X-40-2671G: Silane coupling agent oligomer [manufactured by Shin-Etsu Chemical Co., Ltd.]
Desolite Z7404: Hard coating agent containing ZrO ₂ fine particles [refractive index 1.62, solid content concentration 60.4%, manufactured by JSR Corporation]
DPHA: Mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate [manufactured by Nippon Kayaku Co., Ltd.]
KEP-150: Silica particles having an average particle size of 1.5 μm [refractive index: 1.46, manufactured by Nippon Shokubai Co., Ltd., 30% MEK dispersion, used after dispersion at 10,000 rpm for 20 minutes with a Polytron disperser]
MXS-300: PMMA particles having an average particle diameter of 3 μm [refractive index: 1.49, manufactured by Soken Chemical Co., Ltd., 30% MIBK dispersion, used after dispersion at 10,000 rpm for 20 minutes in a Polytron disperser]
MXS-150H: PMMA particles having an average particle diameter of 1.5 μm [refractive index: 1.49, manufactured by Nippon Shokubai Co., Ltd., 30% MIBK dispersion, used after dispersion at 10,000 rpm for 20 minutes in a Polytron disperser]

(Production of optical film)
The cellulose acylate film casted in the above-mentioned example as a support is unwound in a roll form, and the anti-glare hard coat layer coating liquid A-1 has a gravure pattern of 110 lines / inch and a depth of 65 μm. Using a microgravure roll having a diameter of 50 mm and a doctor blade, it was applied at a transfer speed of 30 m / min, dried at 60 ° C. for 150 seconds, and then an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.). ) Was irradiated with ultraviolet rays having an illuminance of 400 mW / cm ² and an irradiation amount of 200 mJ / cm ² to cure the coating layer, and an antiglare hard coat layer (thickness 6 μm) was formed and wound. Moreover, the coating amount as a coating liquid at this time was about 20 cc / m < ² >.
Similarly, using a microgravure roll having a diameter of 135 mm / inch and a gravure pattern having a depth of 60 μm and a doctor blade, the coating liquid B-1 for the light diffusion layer is rotated at a rotational speed of 45 rpm and a conveying speed. After applying at 20 m / min, drying at 100 ° C. for 40 seconds, and further using a 160 W / cm air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) under a nitrogen purge, irradiation is 400 mW / cm ² . The coating layer was cured by irradiating an amount of 250 mJ / cm ² of ultraviolet rays to form a functional layer of a light diffusion layer (thickness: 3.4 μm) and wound up. The coating amount as a coating solution at this time was about 20 cc / m ² .

(8) Evaluation and result of coating sample [Evaluation of coated surface state (dry unevenness, uneven stripe)]
The coated surface was evaluated for the above coated products. As an evaluation, a method of observing the prepared film through transmission of a fluorescent light source of three wavelengths, and a black sheet or a polarizing plate made black with crossed Nicols on the back surface, reflection of a three-wave fluorescent light or artificial solar light source Evaluation was made by inspection.
As the evaluation of the coated product, the transmission evaluation is strictly judged, but the optical film is within the allowable range from A to C in the reflection evaluation.
The above evaluation results were determined as follows.
A: Unevenness is hardly visible.
B: Slight unevenness is visible, but there is no particular problem.
C: Unevenness is visible but acceptable.
D: Unevenness is visible and is not acceptable.
E: Unevenness is quite strong.
[Evaluation of flatness due to film base]
About the coated product, the swellability of the surface with a pitch of 1 to 2 mm was confirmed as the flatness due to the cellulose acylate film when pasted on the polarizing plate. The acceptable level is indicated by ◯, the level of concern is indicated by △, and the unacceptable level is indicated by ×.

(Production and evaluation results of coated products)
The results of the coated samples of Example Samples 51 to 66 and Comparative Samples 51 to 54 of the present invention are shown in Table 2. In Example Samples 51 to 56 and Comparative Sample 51, if the surface plasticizer amount variation is large, coating unevenness deteriorates. If the surface plasticizer amount variation exceeds ± 25%, the transmission and reflection surface inspections are not acceptable. Further, even in the comparative sample 52 having a large variation in film thickness, a tolerance is not allowed in the transmission and reflection surface inspection. The sample samples 57 and 58 applied to the air surface with little variation in the amount of the surface plasticizer have a good coated product surface shape, but some unevenness due to the flatness of the cellulose acylate of the transparent support is observed.
Moreover, the same tendency was shown also in the Example samples 59-66 using the coating liquid B-1.
Moreover, when A-2, A-3, A-4 is used instead of the coating liquid A-1, and B-2, B-3 is used instead of B-1, the coated surface state in the reflection inspection is improved. did.

(9) Preparation of antireflection film A low refractive index layer was applied to the above-described Example Samples 55 and 63 of the present invention.

(Composition of coating liquid A for low refractive index layer)
Opstar JTA-113 (6%) 13.0g
MEK-ST-L (30%) [Average particle size 45 nm] 1.3 g
Sol liquid a-1 10.6 g
MEK 5.0g
Cyclohexanone 0.6g

  The coating solution was filtered through a polypropylene filter having a pore size of 1 μm to prepare a coating solution A for a low refractive index layer.

(Preparation of coating solution B for low refractive index layer)
In addition to the colloidal silica dispersion of the coating liquid A for the low refractive index layer, 1.95 g of a hollow silica dispersion (refractive index 1.31, average particle size 60 nm, solid content concentration 20%) was used. In the same manner as in the above coating solution A, a coating solution B for a low refractive index layer was prepared.

(Composition of coating liquid C for low refractive index layer)
Opstar JN-7228 (6%) 15.0g
MEK-ST (30%) [Average particle size 15 nm] 0.6 g
MEK-ST-L (30%) [Average particle size 45 nm] 0.8 g
Sol liquid a-1 0.4g
MEK 3.0g
Cyclohexanone 0.6g

  The coating solution was filtered through a polypropylene filter having a pore size of 1 μm to prepare a coating solution C for a low refractive index layer.

(Composition of coating liquid D for low refractive index layer)
Perfluoroolefin copolymer (1) 15.2 g
MEK-ST-L (30%) [Average particle size 45 nm] 1.4 g
Reactive silicone X-22-164B 0.3g
Sol solution a-1 7.3 g
Irgacure 907 0.76g
MEK 301g
Cyclohexanone 9.0g

  The coating solution was filtered through a polypropylene filter having a pore size of 5 μm to prepare a coating solution D for a low refractive index layer.

(Adjustment of coating liquid E for low refractive index layer)
In the coating liquid D for the low refractive index layer, the amount added except that 1.95 g of a hollow silica dispersion (refractive index 1.31, average particle size 60 nm, solid content concentration 20%) was used instead of the colloidal silica dispersion. In the same manner as in the coating liquid D, a coating liquid E for a low refractive index layer was prepared.

  The compounds used are shown below.

-OPSTAR JN: 80 g of fluorine-containing polymer described in JP-A-11-189621, Example 1, 15 g of Cymel 303 as a curing agent (Nippon Cytec Industries, Ltd., 2.0 g of Catalyst 4050 as a curing catalyst (Nippon Cytec Industries, Ltd.) ) Dissolved in MEK to 6% [refractive index 1.42, solid content concentration 6%, manufactured by JSR Corporation]
Opster JTA: JP-A-11-189621, fluorine-containing polymer with an increased amount of HBVE of Example 1 [refractive index: 1.44, solid content concentration: 6%, manufactured by JSR Corporation]
P-1: Perfluoroolefin copolymer (1)
MEK-ST: Colloidal silica dispersion [average particle size 10-20 nm, solid content concentration 30%, manufactured by Nissan Chemical Co., Ltd.]
MEK-ST-L: Colloidal silica dispersion [MEK-ST particle size difference, average particle size 45 nm, solid content concentration 30%, manufactured by Nissan Chemical Co., Ltd.]
Hollow silica: KBM-5103 surface-modified hollow silica sol [surface modification rate vs. silica 30% by mass, CS-60IPA, refractive index 1.31, average particle size 60 nm, shell thickness 10 nm, solid content concentration 20.0%, catalyst conversion Industrial Co., Ltd.]
X-22-164B: reactive silicone [manufactured by Shin-Etsu Chemical Co., Ltd.]
・ Irgacure 907: Photopolymerization initiator [Ciba Specialty Chemicals Co., Ltd.]

(2) Coating of low refractive index layer The cellulose acylate film coated with the above functional layer was unwound again, and the coating solution for the low refractive index layer shown in Table 3 had a line number of 200 lines / inch and a depth of 30 μm. Using a micro gravure roll having a gravure pattern and a diameter of 50 mm and a doctor blade, it was applied under the conditions of a gravure roll rotation speed of 30 rpm and a conveyance speed of 15 m / min, dried at 120 ° C. for 150 seconds, and further dried at 140 ° C. for 8 minutes. Then, using a 240 W / cm air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) under a nitrogen purge, ultraviolet rays with an illuminance of 400 mW / cm ² and an irradiation amount of 900 mJ / cm ² were irradiated, and a low thickness of 100 nm A refractive index layer was formed to prepare an antireflection film and wound up.

In this manner, Example Samples 101 to 108 having a low refractive index layer applied thereto were prepared.
(Saponification treatment of antireflection film)
The antireflection film was subjected to the following treatment.
A 1.5 mol / l aqueous sodium hydroxide solution was prepared and kept at 55 ° C. A 0.01 mol / l dilute sulfuric acid aqueous solution was prepared and kept at 35 ° C. The prepared antireflection film was immersed in the aqueous sodium hydroxide solution for 2 minutes, and then immersed in water to sufficiently wash away the aqueous sodium hydroxide solution. Subsequently, after being immersed in the above-mentioned dilute sulfuric acid aqueous solution for 1 minute, it was immersed in water to sufficiently wash away the dilute sulfuric acid aqueous solution. Finally, the sample was thoroughly dried at 120 ° C.
In this way, saponified antireflection films (invention samples 101 to 108) were produced.

(Evaluation of antireflection film)
About these obtained antireflection film samples, the following items were evaluated. The results are shown in Table 3.

(1) Average reflectance Using a spectrophotometer (manufactured by JASCO Corporation), the spectral reflectance at an incident angle of 5 ° was measured in a wavelength region of 380 to 780 nm. For the results, an integrating sphere average reflectance of 450 to 650 nm was used.

(2) Steel wool scratch resistance evaluation A rubbing test was performed under the following conditions using a rubbing tester.
Evaluation environmental conditions: 25 ° C., 60% RH
Rubbing material: Steel wool (manufactured by Nippon Steel Wool Co., Ltd., grade No. 0000) was wound around the rubbing tip (1 cm × 1 cm) of a tester in contact with the sample, and the band was fixed so as not to move.
Moving distance (one way): 13 cm, rubbing speed: 13 cm / sec, load: 500 g / cm ² , tip contact area: 1 cm × 1 cm, rubbing frequency: 10 reciprocations.
An oil-based black ink was applied to the back side of the rubbed sample and visually observed with reflected light, and scratches on the rubbed portion were evaluated according to the following criteria.
A: Even when viewed very carefully, no scratches are visible.
○: Slightly weak scratches are visible when viewed very carefully.
○ △: Weak scratches are visible.
Δ: Moderate scratches are visible.
Δ × ˜ ×: There is a scratch that can be seen at first glance.

(3) Evaluation of resistance to rubbing with a cotton swab A cotton swab is fixed to the rubbing tip of a rubbing tester, and the upper and lower sides of the sample are fixed with clips in a smooth dish, and the sample and the swab are immersed in water at 25 ° C at room temperature 25 ° C. A rubbing test was performed by applying a load of 500 g and changing the number of rubbing. The rubbing conditions are as follows.
Rubbing distance (one way): 1 cm, rubbing speed: about 2 reciprocations / second The sample after rubbing was observed, and the rubbing resistance was evaluated as follows according to the number of film peeling.
×: Film peeling after 0-10 round trips × Δ: Film peeling after 10-30 round trips Δ: Film peeling after 30-50 round trips ○ △: Film peeling after 50-100 round trips ○: Film peeling after 100-150 round trips ◎: 150 No film peeling even when reciprocating

The above results are shown in Table 3. According to the present invention, an antireflection film having excellent surface shape and high scratch resistance can be obtained with high productivity.

In the inventive samples 101 to 108, when the sol solution b was used in place of the organosilane sol solution a-1 used in the low refractive index layer coating solution, the aging stability of the coating solution was improved and continuous. The suitability for application became high.
Further, in the inventive samples 104 and 108, 10 g of a mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (DPHA, manufactured by Nippon Kayaku Co., Ltd.) was added to the low refractive index layer coating solution E, followed by coating in the same manner. As a result, the scratch resistance was remarkably improved.

[Example 2]
The PVA film was immersed in an aqueous solution of 2.0 g / l iodine and 4.0 g / l potassium iodide at 25 ° C. for 240 seconds, and further immersed in an aqueous solution of boric acid 10 g / l at 25 ° C. for 60 seconds. It introduced into the tenter drawing machine of the form of FIG. 2 described in 2002-86554, it extended | stretched 5.3 time, the tenter was bent like FIG. 2 with respect to the extending | stretching direction, and the width | variety was kept constant hereafter. After drying in an atmosphere of 80 ° C., it was detached from the tenter. The difference in transport speed between the left and right tenter clips was less than 0.05%, and the angle between the center line of the introduced film and the center line of the film sent to the next process was 46 °. Here, | L1-L2 | is 0.7 m, W is 0.7 m, and | L1-L2 | = W. The substantial stretching direction Ax-Cx at the tenter outlet was inclined by 45 ° with respect to the center line 22 of the film sent to the next process. Wrinkles and film deformation at the tenter exit were not observed.
Furthermore, it was bonded to Fuji Photo Film Co., Ltd. Fujitac (cellulose triacetate, retardation value 3.0 nm), which was saponified with an aqueous solution of PVA (Pura-117H, Kuraray Co., Ltd.) 3%, and further 80 ° C. And dried to obtain a polarizing plate having an effective width of 650 mm. The absorption axis direction of the obtained polarizing plate was inclined 45 ° with respect to the longitudinal direction. The polarizing plate had a transmittance at 550 nm of 43.7% and a polarization degree of 99.97%. Further, when the substrate was cut into a size of 310 × 233 mm, a polarizing plate having a 45 ° absorption axis inclined with respect to the side with an area efficiency of 91.5% was obtained.
Next, each film of the inventive sample of Example 1 (saponified) was bonded to the above polarizing plate to produce a polarizing plate with antiglare and antireflection. Using this polarizing plate, a liquid crystal display device having an antireflection layer disposed on the outermost layer was produced. As a result, there was no reflection of external light, and an excellent contrast was obtained. It had visibility.

[Example 3]
After being immersed in a 1.5 mol / l, 55 ° C. NaOH aqueous solution for 2 minutes, it was neutralized and washed with water. 80 μm thick triacetyl cellulose film (TAC-TD80U, manufactured by Fuji Photo Film Co., Ltd.) and the back saponified triacetyl cellulose film of each sample of the present invention of Example 1 were allowed to adsorb iodine to polyvinyl alcohol, A polarizing plate was prepared by adhering and protecting both sides of a stretched polarizer. A liquid crystal display device of a notebook personal computer equipped with a transmissive TN liquid crystal display device (Sumitomo 3M Co., Ltd., which is a polarization separation film having a polarization selection layer) so that the anti-reflection film side is the outermost surface. When the polarizing plate on the viewing side of D-BEF made of the product between the backlight and the liquid crystal cell was replaced, a display device with very high display quality was obtained with very little background reflection.

[Example 4]
A viewing angle widening film as a protective film on the liquid crystal cell side of the polarizing plate on the viewing side of the transmission type TN liquid crystal cell to which the sample of the present invention of Example 1 is attached, and a protective film on the liquid crystal cell side of the polarizing plate on the backlight side (Wide View Film Ace, manufactured by Fuji Photo Film Co., Ltd.) has excellent contrast in the bright room, very wide viewing angles in the top, bottom, left and right, extremely excellent visibility, and high display quality. A device was obtained.
In addition, the inventive samples 104 to 108 (coating liquid B-1 for light diffusion layer) have a scattered light intensity of 30 ° with respect to an emission angle of 0 ° of 0.06%. It was a very good liquid crystal display device with improved viewing angle and improved yellowness in the left-right direction. For comparison, the film produced in the same manner as the inventive samples 104 to 108 except that the crosslinked PMMA particles and silica particles were removed from the coating solution B for light diffusion layer, had a scattered light intensity of 30 ° with respect to an emission angle of 0 °. It was substantially 0%, and the downward viewing angle was increased, and the yellowishness improving effect was not obtained at all.

[Example 5]
Using cellulose acylate having an acetyl substitution degree of 2.94, optical anisotropy reducing agent A-19 was 49.3% (vs. cellulose acylate), and chromatic dispersion regulator UV-102 was 7.6% (vs. cellulose). The cellulose acylate sample 201 having a thickness of 80 μm was prepared by the same film forming method as in Example 1. The retardation Re of the obtained film was −1.0 nm (negative due to the slow axis in the TD direction), and the retardation Rth in the thickness direction was −2.0 nm, both sufficiently small values. When this cellulose acylate film sample was used as a transparent support for the protective film on the cell side of the two protective films of the polarizer and Example 1 of the present invention was used as the protective film on the viewer side of the polarizer, Japanese Patent Application Laid-Open No. Hei 10 Liquid crystal display device described in Example 1 of Japanese Patent No. -48420, an optically anisotropic layer containing discotic liquid crystal molecules described in Example 1 of Japanese Patent Application Laid-Open No. 9-26572, an alignment film coated with polyvinyl alcohol, Evaluations were made on the VA type liquid crystal display device shown in FIGS. 2 to 9 of Kaikai 2000-154261 and the OCB type liquid crystal display device shown in FIGS. 10 to 15 of Japanese Patent Laid-Open No. 2000-154261. The performance with a good contrast viewing angle was obtained.

  A-19

  UV-102

[Example 6]
When the inventive sample of Example 1 was bonded to the glass plate on the surface of the organic EL display device via an adhesive, reflection on the glass surface was suppressed, and a display device with high visibility was obtained.

[Example 7]
Example 1 Using a sample, a polarizing plate with a single-side antireflection film was prepared, and a λ / 4 plate was bonded to the opposite surface of the polarizing plate on the side having the antireflection film, and the glass on the surface of the organic EL display device When affixed to the plate, surface reflection and reflection from the inside of the surface glass were cut, and a display with extremely high visibility was obtained.

(A) is a cross-sectional schematic diagram which shows the layer structure of an anti-glare antireflection film, (b) is a cross-sectional schematic diagram which shows the layer structure of the antireflection film excellent in antireflection performance.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Antireflection film 2 Transparent support 3 Hard coat layer 4 Anti-glare hard coat layer 5 Low refractive index layer 6 Fine particle 7 Middle refractive index layer 8 High refractive index layer

Claims (10)

An optical film having functional layers at least one layer is provided on a transparent support of long, thickness irregularity of the transparent support, not more than ± 5% of the average thickness, the transparent support in For a total of 25 points, the plasticizer amount is 3 to 10% by mass, and 5 points are equally spaced in the width direction of 1 m and 5 points in the longitudinal direction of 1 m on the functional layer coating surface side of the transparent support. An optical film characterized in that the variation in the measured amount of surface plasticizer is ± 20% or less of the average remaining amount of surface plasticizer.
Here, the surface plasticizer amount refers to the amount of plasticizer from the surface to 2 μm thickness calculated from the plasticizer absorption peak intensity ratio by ATR-IR measurement. The thickness unevenness of transparency support in the longitudinal direction more than 1m and width 1m or more ranges, ± 5% or less of the average thickness, moreover variation in surface plasticizer amount of the functional layer coating side of the support, 2. The optical film according to claim 1, wherein the optical film is within ± 20% of the average residual amount of the surface plasticizer within a range of 1 m or more in the longitudinal direction and 1 m or more in the width direction.   3. The optical film according to claim 1, wherein the transparent support has an average thickness of 20 μm or more and 120 μm or less.   The optical film according to claim 1, wherein the transparent support is cellulose triacetate. After a cellulose acylate film having a plasticizer amount of 3 to 10% by mass is formed and the residual solvent amount of the cellulose acylate film is 5% by mass or less, a heat treatment at 100 ° C. to 160 ° C. is performed for 60 seconds or more. The production of an optical film according to claim 1, wherein the production is performed for 900 seconds or less, and at least one functional layer is coated on the transparent support using the cellulose acylate film as a transparent support. Method.   The optical film according to claim 1, wherein at least one functional layer is a low refractive index layer and has an antireflection ability. 7. The optical film according to claim 1 , wherein a solvent that partially dissolves or swells the transparent support is used in the coating liquid that forms at least one functional layer. The hydrolyzate of organosilane represented by the following general formula 1 and / or a partial condensate thereof are contained in at least one functional layer, according to any one of claims 1 to 4, 6, or 7 The optical film as described.
General formula 1

(In General Formula 1, R ¹ represents a hydrogen atom, a methyl group, a methoxy group, an unsubstituted alkoxycarbonyl group, a cyano group, a fluorine atom, or a chlorine atom.
Y represents a single bond, * -COO-**, * -CONH-**, or * -O-**.
L represents a divalent linking chain.
R ^{2 to} R ⁴ each independently represent a halogen atom, a hydroxyl group, an unsubstituted alkoxy group, or an unsubstituted alkyl group.
R ⁵ represents a hydrogen atom or an unsubstituted alkyl group.
R ⁶ represents a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group.
l represents a number satisfying the mathematical formula of l = 100−m, and m represents a number from 0 to 50.
The hydrolyzate and / or its partial condensate may be a hydrolyzate and / or its partial condensate of a mixture of a plurality of compounds represented by general formula 1 having specific l and m. Good. ) The optical film in any one of Claims 1-4 and 6-8 is used for one of the two protective films of the polarizer in a polarizing plate, The polarizing plate characterized by the above-mentioned. An image display device, wherein the optical film according to claim 6 or the polarizing plate according to claim 9 is used on an outermost surface of a display.

Images