JP5155545B2 - Antireflection film, method for producing the same, polarizing plate using the antireflection film, and image display device - Google Patents

Description

  The present invention relates to an antireflection film, a polarizing plate using the antireflection film, and an image display device using the antireflection film or the polarizing plate on the outermost surface of a display.

  In general, an antireflection film is used for an image display device such as a cathode ray tube display (CRT), a plasma display (PDP), an electroluminescence display (ELD), a liquid crystal display (LCD), etc. In order to prevent reflection of images and images, it is arranged on the outermost surface of the display so as to reduce the reflectance by using the principle of optical interference.

  Such an antireflection film can be generally produced by forming a low refractive index layer having an appropriate thickness on a support or a high refractive index layer formed thereon. As a material for the low refractive index layer, a material having a refractive index as low as possible is desired from the viewpoint of antireflection performance, and at the same time, since it is used for the outermost surface of the display, high antifouling property and scratch resistance are required. In order to realize high scratch resistance in a thin film having a thickness of around 100 nm, it is important to increase the strength of the coating itself.

  As a polymer for forming a low refractive index layer, it is well known that a low refractive index fluorine-containing polymer is cured, and various curing methods are known, for example, having a hydroxyl group or the like. It has been generally performed to cure polymers with various curing agents (Patent Documents 1 to 3). However, it was not sufficient in terms of film hardness, and an improvement was desired.

  As means for lowering the refractive index of the material, there are also means for lowering the density (introducing voids) in addition to (1) means for introducing fluorine atoms, as in Patent Documents 1 to 3 above. Both have the problem that the film strength is impaired and the scratch resistance is lowered.

  As a means for greatly improving antifouling properties and scratch resistance while maintaining a low refractive index, imparting slipperiness to the surface is effective. Techniques such as introduction of fluorine and introduction of silicon are effective for imparting slipperiness. In particular, by adding a small amount of a silicone compound to a low refractive index material, the effect of developing slipperiness, the effect of improving antifouling properties, and the effect of improving scratch resistance are remarkably exhibited. However, there are various problems such as compatibility with low refractive index layer materials, bleeding out over time or at high temperatures, transfer of silicone components to contact media, performance degradation associated with these, and contamination of production lines. It was.

  Particularly in an antireflection film, generation of haze due to insufficient compatibility is a serious problem because optical performance deteriorates. Further, when the film after the application of the low refractive index layer is wound, a silicone compound may adhere to the back surface of the film, which is a serious problem because it hinders subsequent processing steps. That is, there is a demand for a technique in which only the siloxane sites are effectively segregated on the surface and the remaining sites bonded to silicon are effectively anchored in the low refractive index layer coating.

In order to solve this problem, a technique (Patent Documents 4 to 7) for applying a fluorine-containing olefin copolymer and its antireflection film, in which a polysiloxane block copolymer component is introduced using a silicone-based macroazo initiator, has been proposed. ing.
JP 57-34107 A JP-A 61-275311 JP-A-8-92323 JP-A-11-189621 Japanese Patent Laid-Open No. 11-228631 JP 2000-17028 A JP 2000-313709 A

  Although these techniques greatly improve the uniformity and durability of the coating, it is possible to produce fluorine-containing olefin copolymers, such as increasing the amount of silicone-based macroazo initiator when trying to arbitrarily control the slipperiness of the material. It was necessary to deal with in the stage and was complicated. Therefore, there has been a demand for the development of a technology capable of appropriately controlling the slipperiness with respect to the existing fluorine-containing olefin copolymer.

  From the above background, there has been a demand for a technique that can control the amount of silicone component introduced at will without impairing the uniformity of the low refractive index layer coating.

  An object of the present invention is to provide, firstly, a coating type antireflection film suitable for mass production, and secondly, an antireflection film having a low reflectivity and excellent in antifouling property and scratch resistance. Thirdly, it is to provide a polarizing plate using such an antireflection film as a protective film for the polarizing film, and fourthly, such an antireflection film or An object of the present invention is to provide an image display device which is excellent in antifouling property and scratch resistance on the surface and prevented from being reflected by being used for a polarizing plate.

一般式（１）中、Ｒ ^１１ 、Ｒ ^１２ は、水素原子、アルキル基、又はアリール基を表す。ｐは１０〜５００の整数を表す。
一般式（２）：

一般式（２）中、Ｘは上記一般式（１）で表されるポリシロキサン構造を含む単位を表す。Ｙは任意のビニルモノマーに基づく重合単位を表し、単一成分であっても複数の成分で構成されていてもよい。Ｒ ^２１ は水素原子又はメチル基を表し、Ｌ ^２１ は単結合又は２価の連結基を表す。ｘ〜ｚはそれぞれ各構成成分のモル分率（％）を表し、１０≦ｘ＜１００、０≦ｙ≦５０、０＜ｚ≦５０、０＜ｙ＋ｚ≦９０を満たす値を表す。
〔２〕
含フッ素共重合体が、下記一般式（３）で表される〔１〕に記載の反射防止フィルム。
一般式（３）：

一般式（３）中、Ｒｆ ^１１ は炭素数１〜５のペルフルオロアルキル基を表し、Ｒｆ ^１２ は炭素数１〜３０の直鎖、分岐又は脂環構造を有する含フッ素アルキル基を表し、エーテル結合を有していてもよい。Ｂは水酸基含有モノマーに基づく重合単位を表す。Ａは任意のビニルモノマーに基づく重合単位を表し、単一成分であっても複数の成分で構成されていてもよい。ａ〜ｄはそれぞれ各構成成分のモル分率（％）を表し、３０≦ａ＋ｂ≦９０、５≦ａ≦９０、０≦ｂ≦７０、０≦ｃ≦５０、１０≦ｄを満たす値を表す。
〔３〕
低屈折率層を形成する塗布液組成物が、さらに水酸基と反応可能な架橋剤を含む〔１〕又は〔２〕に記載の反射防止フィルム。
〔４〕
架橋剤が、１分子中に、窒素原子に隣接する、アルコキシ基で置換された炭素原子が２個以上存在する化合物である〔３〕に記載の反射防止フィルム。
〔５〕
主鎖に下記一般式（１）で表されるポリシロキサン構造を有する構成成分、及び側鎖に水酸基を含有する構成成分を含み、且つフッ素を含まない下記一般式（２）で表される共重合体と、
含フッ素共重合体
とを含有する塗布液組成物を硬化させることによって低屈折率層を形成する工程を有する反射防止フィルムの製造方法。
一般式（１）：

一般式（１）中、Ｒ ^１１ 、Ｒ ^１２ は、水素原子、アルキル基、又はアリール基を表す。ｐは１０〜５００の整数を表す。
一般式（２）：

一般式（２）中、Ｘは上記一般式（１）で表されるポリシロキサン構造を含む単位を表す。Ｙは任意のビニルモノマーに基づく重合単位を表し、単一成分であっても複数の成分で構成されていてもよい。Ｒ ^２１ は水素原子又はメチル基を表し、Ｌ ^２１ は単結合又は２価の連結基を表す。ｘ〜ｚはそれぞれ各構成成分のモル分率（％）を表し、１０≦ｘ＜１００、０≦ｙ≦５０、０＜ｚ≦５０、０＜ｙ＋ｚ≦９０を満たす値を表す。
〔６〕
〔１〕〜〔４〕のいずれかに記載の反射防止フィルムが、偏光板における偏光膜の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。
〔７〕
〔１〕〜〔４〕のいずれかに記載の反射防止フィルム、又は〔６〕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、前記〔１〕〜〔７〕に係る発明であるが、以下、それ以外の事項（例えば、下記［１］〜［７］）についても記載している。 The object of the present invention has been achieved by the present invention of the following [ 1 ] to [ 7 ] .
[1]
The main chain contains a component having a polysiloxane structure represented by the following general formula (1) and a side chain containing a component having a hydroxyl group and does not contain fluorine. A polymer;
Fluorine-containing copolymer
An antireflection film having a low refractive index layer formed by curing a coating liquid composition containing
General formula (1):

In General Formula (1), R ¹¹ and R ¹² represent a hydrogen atom, an alkyl group, or an aryl group. p represents an integer of 10 to 500.
General formula (2):

In general formula (2), X represents a unit containing a polysiloxane structure represented by general formula (1). Y represents a polymerized unit based on an arbitrary vinyl monomer, and may be composed of a single component or a plurality of components. R ²¹ represents a hydrogen atom or a methyl group, and L ²¹ represents a single bond or a divalent linking group. x to z each represents a mole fraction (%) of each constituent component, and represents values satisfying 10 ≦ x <100, 0 ≦ y ≦ 50, 0 <z ≦ 50, and 0 <y + z ≦ 90.
[2]
The antireflection film according to [1], wherein the fluorine-containing copolymer is represented by the following general formula (3).
General formula (3):

In the general formula (3), ^{Rf 11} represents a perfluoroalkyl group having 1 to 5 carbon atoms, ^{Rf 12} represents a fluorine-containing alkyl group having a straight-chain, branched or alicyclic structure having from 1 to 30 carbon atoms, an ether bond You may have. B represents a polymerized unit based on a hydroxyl group-containing monomer. A represents a polymerization unit based on an arbitrary vinyl monomer, and may be a single component or a plurality of components. a to d each represent a mole fraction (%) of each constituent component, and represent values satisfying 30 ≦ a + b ≦ 90, 5 ≦ a ≦ 90, 0 ≦ b ≦ 70, 0 ≦ c ≦ 50, and 10 ≦ d. .
[3]
The antireflection film according to [1] or [2], wherein the coating liquid composition forming the low refractive index layer further contains a crosslinking agent capable of reacting with a hydroxyl group.
[4]
The antireflection film according to [3], wherein the cross-linking agent is a compound in which two or more carbon atoms substituted with an alkoxy group are present adjacent to a nitrogen atom in one molecule.
[5]
The main chain contains a component having a polysiloxane structure represented by the following general formula (1) and a side chain containing a component having a hydroxyl group and does not contain fluorine. A polymer;
Fluorine-containing copolymer
The manufacturing method of the antireflection film which has the process of forming a low-refractive-index layer by hardening the coating liquid composition containing these.
General formula (1):

In General Formula (1), R ¹¹ and R ¹² represent a hydrogen atom, an alkyl group, or an aryl group. p represents an integer of 10 to 500.
General formula (2):

In general formula (2), X represents a unit containing a polysiloxane structure represented by general formula (1). Y represents a polymerized unit based on an arbitrary vinyl monomer, and may be composed of a single component or a plurality of components. R ²¹ represents a hydrogen atom or a methyl group, and L ²¹ represents a single bond or a divalent linking group. x to z each represents a mole fraction (%) of each constituent component, and represents values satisfying 10 ≦ x <100, 0 ≦ y ≦ 50, 0 <z ≦ 50, and 0 <y + z ≦ 90.
[6]
A polarizing plate, wherein the antireflection film according to any one of [1] to [4] is used for one of the two protective films of the polarizing film in the polarizing plate.
[7]
An anti-reflection film according to any one of [1] to [4] or a polarizing plate according to [6] is used on the outermost surface of a display.
The present invention relates to the above [1] to [7], but hereinafter, other matters (for example, the following [1] to [7]) are also described.

[1] A copolymer containing a constituent having a polysiloxane structure represented by the following general formula (1) in the main chain and a constituent containing a hydroxyl group in the side chain and not containing fluorine;
An antireflection film comprising a low refractive index layer formed by curing a coating liquid composition containing a fluorine-containing copolymer.
General formula (1):

In general formula (1), R ¹¹ and R ¹² represent a hydrogen atom, an alkyl group, or an aryl group. p represents an integer of 10 to 500.

[2] The antireflection film as described in [1], wherein the fluorine-free copolymer is represented by the following general formula (2).
General formula (2):

In general formula (2), X represents a unit containing a polysiloxane structure represented by general formula (1). Y represents a polymerized unit based on an arbitrary vinyl monomer, and may be composed of a single component or a plurality of components. R ²¹ represents a hydrogen atom or a methyl group, and L ²¹ represents a single bond or a divalent linking group. x to z each represents a mole fraction (%) of each component, and 10 ≦ x <100
, 0 ≦ y ≦ 50, 0 <z ≦ 50, 0 <y + z ≦ 90.

[3] The antireflection film according to [1] or [2], wherein the fluorine-containing copolymer is represented by the following general formula (3).
General formula (3):

In the general formula (3), Rf ¹¹ represents a perfluoroalkyl group having 1 to 5 carbon atoms, Rf ¹² represents a fluorine-containing alkyl group having a straight-chain, branched or alicyclic structure having from 1 to 30 carbon atoms, an ether bond You may have. B represents a polymerized unit based on a hydroxyl group-containing monomer. A represents a polymerization unit based on an arbitrary vinyl monomer, and may be a single component or a plurality of components. a to d each represent a mole fraction (%) of each constituent component, and represent values satisfying 30 ≦ a + b ≦ 90, 5 ≦ a ≦ 90, 0 ≦ b ≦ 70, 0 ≦ c ≦ 50, and 10 ≦ d. .

[4] The antireflection film as described in any one of [1] to [3] above, wherein the coating liquid composition forming the low refractive index layer further contains a crosslinking agent capable of reacting with a hydroxyl group.
[5] The antireflection film as described in [4] above, wherein the crosslinking agent is a compound having two or more carbon atoms substituted with an alkoxy group adjacent to a nitrogen atom in one molecule.

[6] A polarizing plate, wherein the antireflection film according to any one of [1] to [5] is used for one of the two protective films of the polarizer in the polarizing plate.
[7] An image display device, wherein the antireflection film according to any one of [1] to [5] or the polarizing plate according to [6] is used on an outermost surface of a display.

  The composition used in the present invention has a low refractive index, imparts slipperiness, and forms a film excellent in strength. An antireflection film containing a low refractive index layer obtained by curing this composition has high antireflection performance, excellent antifouling properties and scratch resistance, and excellent adhesion to a substrate. The polarizing plate and the liquid crystal display device using this antireflection film have excellent effects that the reflection of external light is sufficiently prevented and that the antifouling property and scratch resistance are also high.

<Antireflection film>
The antireflection film of the present invention comprises a component having a polysiloxane structure represented by the general formula (1), a component containing a hydroxyl group in a side chain, and a copolymer containing no fluorine, and a fluorine-containing It has a low refractive index layer formed by curing a composition containing a copolymer. The antireflection film may have a single-layer structure consisting of only a low refractive index layer as an antireflection layer, and has an antireflection layer having a multilayer structure laminated with a medium / high / low refractive index layer, a hard coat layer, or the like. May be. A multilayer structure is preferable, and a structure in which three or more layers of middle, high, and low refractive index layers are stacked is particularly preferable. It is preferable to form an antireflection layer on a transparent support in advance to form an antireflection film and then place it in the image display device.

[Typical layer structure of antireflection film]
Hereinafter, a basic configuration of an antireflection film suitable as an embodiment 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 1a includes a transparent support 2, a hard coat layer 3, a high refractive index layer 4, and a low antireflection film. The refractive index layer 5 has a layer structure in the order. The refractive index of the high refractive index layer 4 is preferably in the range of 1.50 to 2.00, and the refractive index of the low refractive index layer 5 is preferably in the range of 1.30 to 1.44.

  In the present invention, the hard coat layer may be provided separately from the high refractive index layer as described above, or may be a high refractive index hard coat layer having the function of the high refractive index layer. Further, the hard coat layer may be a single layer or may be composed of a plurality of layers, for example, 2 to 4 layers. Further, the hard coat layer may be omitted. Accordingly, the hard coat layer shown in FIG. 1 is not essential, but it is preferable that any of these hard coat layers is applied to impart film strength. The low refractive index layer is coated on the outermost layer.

  The cross-sectional view schematically shown in FIG. 1 (b) is another example of the antireflection film of the present invention. The antireflection film 1b comprises a transparent support 2, a hard coat layer 3, a medium refractive index 6, a high refractive index. It has a layer structure in the order of a refractive index layer 4 and a low refractive index layer (outermost layer) 5. The transparent support 2, the medium refractive index layer 6, the high refractive index layer 4, 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. 1B, as described in JP-A-59-50401, the medium refractive index layer is represented by the following mathematical formula (1), and the high refractive index layer is represented by the following mathematical formula (2). It is preferable that the low refractive index layer satisfies the following formula (3) in that an antireflection film having more excellent antireflection performance can be produced.
Formula (1): (hλ / 4) × 0.7 <n ₁ d ₁ <(hλ / 4) × 1.3
Formula (2): (iλ / 4) × 0.7 <n ₂ d ₂ <(iλ / 4) × 1.3
Formula (3): (jλ / 4) × 0.7 <n ₃ d ₃ <(jλ / 4) × 1.3

In formulas (1) to (3), h is a positive integer (generally 1, 2 or 3), i is a positive integer (typically 1, 2 or 3), and j is a positive odd number (generally 1). ). n ₁ , n ₂ and n ₃ are the refractive indexes of the medium refractive index layer, the high refractive index layer and the low refractive index layer, respectively, and d ₁ , d ₂ and d ₃ are the medium refractive index layer, the high refractive index layer and the high refractive index layer, respectively. It is the layer thickness (nm) of the refractive index layer and 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 is represented by the following mathematical formula (1-1), the high refractive index layer is represented by the following mathematical formula (2-1), and the low refractive index layer is represented by the following mathematical formula (3-1). It is particularly preferable that each of these is satisfied. Here, λ is 500 nm, h is 1, i is 2, and j is 1.

Formula (1-1): (hλ / 4) × 0.80 <n ₁ d ₁ <(hλ / 4) × 1.00
Formula (2-1): (iλ / 4) × 0.75 <n ₂ d ₂ <(iλ / 4) × 0.95
Formula (3-1): (jλ / 4) × 0.95 <n ₃ d ₃ <(jλ / 4) × 1.05

  The high refractive index, medium refractive index, and low refractive index described herein 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.

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

Furthermore, the low refractive index layer preferably satisfies the formula (3) as described above from the viewpoint of reducing the reflectance.
Formula (3): (jλ / 4) × 0.7 <n ₃ d ₃ <(jλ / 4) × 1.3

In formula (3), j, n ₃ , d ₃ and λ are as described above, and λ is a value in the range of 380 to 680 nm.
In addition, satisfy | filling said Numerical formula (3) means that j (positive odd number, usually 1) which satisfy | fills Numerical formula (3) exists in the said wavelength range.

[Material for low refractive index layer]
{A copolymer having a polysiloxane structure represented by the following general formula (1) in the main chain and a component containing a hydroxyl group in the side chain and not containing fluorine: polysiloxane structure-containing copolymer Combined (S)}
The low refractive index layer in the antireflection film of the present invention has a polysiloxane structure represented by the general formula (1) in the main chain for the purpose of improving scratch resistance by imparting slipperiness and imparting antifouling properties. A copolymer (S) containing a component and a component containing a hydroxyl group in the side chain and not containing fluorine (hereinafter also referred to simply as a copolymer containing no fluorine or a polysiloxane structure-containing copolymer (S)) .)) Is cured together with the fluorinated copolymer. The amount of the siloxane component introduced into the copolymer (S) having a polysiloxane structure can be freely controlled by appropriately adjusting the addition amount. Furthermore, due to the surface uneven distribution of siloxane and the presence of hydroxyl groups, only the siloxane sites can be effectively segregated on the surface and can be anchored effectively in the low refractive index layer coating.
General formula (1):

In general formula (1), R ¹¹ and R ¹² represent a hydrogen atom, an alkyl group, or an aryl group. As an alkyl group, C1-C4 is preferable and a methyl group, a trifluoromethyl group, an ethyl group etc. are mentioned as an example. The aryl group preferably has 6 to 20 carbon atoms, and examples thereof include a phenyl group and a naphthyl group. Among these, a methyl group and a phenyl group are preferable, and a methyl group is particularly preferable. p represents an integer of 10 to 500, preferably 50 to 300, and particularly preferably 100 to 250.

  As a synthesis method of a copolymer containing the constituent component (X) having a polysiloxane structure represented by the general formula (1), several methods have been conventionally proposed.

  For example, J. et al. C. Saam et al., “Macromolecules”, Vol. 3, page 1 (1970), reported that a styrene-dimethylsiloxane block copolymer was obtained by an anionic polymerization method (hereinafter, this method is called an anionic polymerization method). .

  In addition, in “Makromol. Chem., Rapid Commun.”, Vol. 5, page 559 (1984), a vinyl acetate-dimethylsiloxane block copolymer is obtained by coupling reaction between prepolymers having functional groups. (This method is hereinafter referred to as a prepolymer method).

  Furthermore, Hiroshi Inoue et al. In “Science of Polymer Science Proceedings”, 34, 293 (1984), methyl methacrylate-dimethylsiloxane block copolymer by radical polymerization with azo group-containing polysiloxane amide having radical polymerization initiation ability. It has been reported that a coalescence was obtained (this method is hereinafter referred to as a polymer initiator method).

However, in the anionic polymerization method and the prepolymer method, vinyl group monomers that can be applied to the reaction are limited, and the reaction process becomes multi-stage and the reaction conditions become difficult to use industrially. Yes. In order to produce a block copolymer industrially, it can be synthesized using radical polymerization, can be applied to many vinyl monomers, and preferably has few reaction steps.

  From the above viewpoint, the polysiloxane-containing copolymer (S) used in the present invention is preferably produced by a polymer initiator method. Such a polymer initiator is, for example, a polysiloxane compound having a radical-generating group such as an azo group or a peroxy group. Such an initiator can be synthesized as described in, for example, Japanese Patent Publication No. 6-104711 and Japanese Patent Laid-Open No. 6-93100.

(Preferred examples of polymer initiator)
Examples of preferred polymer initiators are shown below, but the present invention is not limited thereto.

Moreover, it is essential that the copolymer (S) containing a polysiloxane structure used in the present invention contains a constituent component (Z) containing a hydroxyl group in the side chain. By having the hydroxyl group, crosslinking is possible, and an effect of preventing transfer can be obtained. Moreover, it is preferable that the copolymer (S) containing a polysiloxane structure is a structure represented by General formula (2).
General formula (2):

In general formula (2), X represents a unit containing a polysiloxane structure represented by general formula (1). Y represents a polymerized unit based on an arbitrary vinyl monomer, and may be composed of a single component or a plurality of components. R ²¹ represents a hydrogen atom or a methyl group, and L ²¹ represents a single bond or a divalent linking group. x to z each represents a mole fraction (%) of each constituent component, and represents values satisfying 10 ≦ x <100, 0 ≦ y ≦ 50, 0 <z ≦ 50, and 0 <y + z ≦ 90.

Hereinafter, the polymer unit represented by the following general formula (4) in the copolymer (S) used in the present invention will be described.
General formula (4):

In the general formula (4), R ²¹ represents a hydrogen atom or a methyl group. L ²¹ represents a single bond, —O—, —CO—, —NH—, —CO—NH—, —COO—, —O—COO—, a substituted or unsubstituted alkylene group, an arylene group, or a heterocyclic group. And a divalent linking group selected from a combination thereof, among which a combination of —COO— and an alkylene group is preferable.

  Hereinafter, although the preferable example of the polymerization unit represented by the said General formula (4) is shown, this invention is not limited to this.

  The copolymer (S) containing the polysiloxane structure used in the present invention represented by the general formula (2) has adhesion to a substrate, solubility in a solvent, and other coating liquid compositions. In addition to those described above from various viewpoints such as compatibility and transparency, other components (Y) may be included. Examples of monomers constituting such a polymerized unit include methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, cyclohexyl acrylate, methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, stearyl methacrylate, methyl vinyl ether, ethyl vinyl ether, propyl vinyl ether, isobutyl vinyl ether, styrene, α-methyl styrene, acrylonitrile, methacrylate Lontri And the like can be given.

  From the viewpoints described above, the polysiloxane-containing copolymer (S) in the present invention is a component containing a hydroxyl group represented by the general formula (4) in addition to the component (X) having a polysiloxane structure ( Z) and an optional component (Y) are preferred.

  The molar fraction (%) of each component is selected so as to satisfy the relationship of 10 ≦ x <100, 0 ≦ y ≦ 50, 0 <z ≦ 50, 0 <y + z ≦ 90.

  In the polysiloxane-containing copolymer (S) in the present invention, the constituent component (X) is an essential component for imparting sufficient scratch resistance to the material, and for imparting transparency and antifouling durability. X representing the mole fraction (%) of X) is preferably 50 ≦ x <100, and more preferably 85 ≦ x <100.

  In the copolymer (S), the component (Z) is a unit containing a hydroxyl group that is a crosslinking group for preventing transfer, but the amount of (Z) introduced is too low in the ratio of (X), It is preferable to select appropriately within a range in which sufficient scratch resistance, antifouling durability and transparency are not easily obtained. Therefore, the preferable range of the molar fraction of (Z) is 0 <z ≦ 40, and more preferably 0 <z ≦ 15.

  In the copolymer (S), the component (Y) other than (X) and (Z) is adhesive to the substrate, soluble in the solvent, compatible with other coating liquid compositions, and transparent. However, the amount of (Y) introduced is too low for the ratio of (X) to provide sufficient scratch resistance, antifouling durability, and transparency. It is preferable to select appropriately within a range that does not become difficult to obtain. Therefore, the preferable range of the molar fraction of (Y) is 0 ≦ y ≦ 40, and more preferably 0 ≦ y ≦ 15.

  Although the specific example of a polymer useful by this invention is shown in Table 1, this invention is not limited to these. In addition, the number in Table 1 represents the mole fraction of each polymerization unit.

In addition, the abbreviation in a table | surface represents the following.
t-BuMA: t-butyl methacrylate MMA: methyl methacrylate

(Synthesis of polysiloxane structure-containing copolymer (S))
The polysiloxane-containing copolymer (S) used in the present invention can be synthesized by various polymerization methods such as solution polymerization, precipitation polymerization, suspension polymerization, bulk polymerization, and emulsion polymerization. At this time, it can be synthesized 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, 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 must 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 the polymerization can be carried out in the range of 50 to 120 ° C. preferable.

  When introducing a polysiloxane moiety using a polymer initiator, other radical initiators can be used in combination as required.

  Examples of the radical initiator that can be used in combination include diacyl peroxides such as acetyl peroxide and benzoyl peroxide; ketone peroxides such as methyl ethyl ketone peroxide and cyclohexanone peroxide; hydroperoxides such as hydrogen peroxide, t-butyl hydroperoxide and cumene hydroperoxide; Dialkyl peroxides such as di-t-butyl peroxide, dicumyl peroxide, dilauroyl peroxide; peroxy esters such as t-butyl peroxyacetate and t-butyl peroxypivalate; azobisisobutyronitrile, azobisisovalero Examples thereof include azo compounds such as nitriles; persulfates such as ammonium persulfate, sodium persulfate, and potassium persulfate.

  The radical polymerization initiator may be used in combination with an inorganic reducing agent such as sodium hydrogen sulfite and sodium pyrosulfite, and an organic reducing agent such as cobalt naphthenate and dimethylaniline, as necessary.

  As the reprecipitation solvent for the obtained polymer, water, isopropanol, hexane, methanol, and a mixed solvent thereof are preferable.

  In the coating liquid composition used in the present invention, the fluorine-free copolymer is preferably contained in a proportion of 0.01 to 20% by mass with respect to the fluorine-containing copolymer, and 0.05 to 15 More preferably, it is contained in a proportion of mass%, more preferably 0.1 to 10 mass%.

{Fluorine-containing copolymer}
The low refractive index layer in the antireflection film of the present invention includes a component having a polysiloxane structure represented by the general formula (1) in the main chain and a component having a hydroxyl group in the side chain, and fluorine. It is formed by curing a composition containing a fluorine-containing copolymer together with a copolymer (S) not containing. Moreover, it is preferable that a fluorine-containing copolymer is a structure represented by General formula (3).
General formula (3):

In the general formula (3), Rf ¹¹ represents a perfluoroalkyl group having 1 to 5 carbon atoms, and Rf ¹² includes a linear, branched or alicyclic structure having 1 to 30 carbon atoms, preferably 1 to 15 carbon atoms. It is a fluorine alkyl group and may have an ether bond.

The polymer unit having Rf ¹¹ and the polymer unit having Rf ¹² are both polymer units based on a fluorine-containing vinyl monomer. Specific examples of the fluorine-containing vinyl monomer include fluoroolefins (for example, fluoroethylene, vinylidene fluoride). , Tetrafluoroethylene, hexafluoroethylene, hexafluoropropylene, etc.), perfluoro (alkyl vinyl ethers) {eg, perfluoro (methyl vinyl ether), perfluoro (ethyl vinyl ether), perfluoro (propyl vinyl ether)}, perfluoro (alkoxyalkyl vinyl ether) s {For example, perfluoro (propoxypropyl vinyl ether)}. These may be used alone or in combination of two or more.

  From the viewpoint of refractive index, solubility, transparency, availability, etc., hexafluoropropylene alone or a combination of hexafluoropropylene and perfluoro (alkyl vinyl ether) or perfluoro (alkoxyalkyl vinyl ether) is particularly preferable.

  In the general formula (3), A represents a polymerization unit based on an arbitrary vinyl monomer, and is not particularly limited as long as it is a constituent component based on a monomer copolymerizable with hexafluoropropylene. It can be appropriately selected from various viewpoints such as adhesion to the material, Tg of the polymer (contributing to film hardness), solubility in a solvent, transparency, slipperiness, and dust / stain resistance. A plurality of these vinyl monomers may be combined depending on the purpose, and are preferably introduced in a range of 0 to 50 mol% in the copolymer in total, and in a range of 0 to 40 mol%. More preferably, it is particularly preferably in the range of 0 to 30 mol%.

  The vinyl monomer unit that can be used as A is not particularly limited. For example, olefins (ethylene, propylene, isoprene, vinyl chloride, vinylidene chloride, etc.), acrylates (methyl acrylate, methyl acrylate, ethyl acrylate) , 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate), methacrylates (methyl methacrylate, ethyl methacrylate, butyl methacrylate, 2-hydroxyethyl methacrylate, etc.), styrene derivatives (styrene, p-hydroxymethyl) Styrene, p-methoxystyrene, etc.), fluorine-containing vinyl ethers, vinyl ethers (methyl vinyl ether, ethyl vinyl ether, cyclohexyl vinyl ether, etc.), vinyl esters (vinyl acetate, vinyl propionate, cinnamic acid) Nyl), unsaturated carboxylic acids (acrylic acid, methacrylic acid, crotonic acid, maleic acid, itaconic acid, etc.), acrylamides (N, N-dimethylacrylamide, Nt-butylacrylamide, N-cyclohexylacrylamide, etc.), Examples include methacrylamides (N, N-dimethylmethacrylamide), acrylonitrile and the like.

  Of the vinyl monomers that can be used in combination, vinyl ethers or fluorine-containing vinyl ethers are preferably introduced from the viewpoint of further lowering the refractive index.

  The copolymer used in the present invention preferably has a polymer unit (hereinafter also referred to as B component) based on a hydroxyl group-containing monomer represented by B in the general formula (3) as a constituent component. Since the hydroxyl group has a function of curing by reacting with a crosslinking agent, a higher hydroxyl group content is preferable because a hard film can be formed. As the hydroxyl group-containing vinyl monomer, any vinyl ethers, (meth) acrylates, styrenes and the like can be used as long as they are copolymerizable with the above-described fluorine-containing monomer polymerization unit. For example, when perfluoroolefin (such as hexafluoropropylene) is used as the fluorine-containing monomer, it is preferable to use a hydroxyl group-containing vinyl ether having good copolymerization properties, specifically 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether. , 6-hydroxyhexyl vinyl ether, 8-hydroxyoctyl vinyl ether, diethylene glycol vinyl ether, triethylene glycol vinyl ether, 4- (hydroxymethyl) cyclohexyl methyl vinyl ether, and the like are preferable. These hydroxyl group-containing vinyl monomers may be introduced alone or in combination of two or more, and the content is preferably 10 mol% or more, more preferably 20 to 60 mol%, and more preferably 25 to 50 Mole% is particularly preferred.

  a, b, c, and d represent mol% of each constituent component, and represent values satisfying 30 ≦ a + b ≦ 90, 5 ≦ a ≦ 90, 0 ≦ b ≦ 70, 0 ≦ c ≦ 50, and 10 ≦ d. . Preferably, 35 ≦ a + b ≦ 70, 30 ≦ a ≦ 60, 0 ≦ b ≦ 30, 0 ≦ c ≦ 40, 20 ≦ d ≦ 60, particularly preferably 40 ≦ a + b ≦ 60, 40 ≦ a ≦. 55, 0 ≦ b ≦ 20, 0 ≦ c ≦ 30, 25 ≦ d ≦ 50.

The mass average molecular weight (Mw) of the fluorinated copolymer represented by the general formula (3) is preferably 10 ³ to 10 ⁶ , more preferably 5 × 10 ^{3 to} 5 × 10 ⁵ , particularly The case of 10 ⁴ to 10 ⁵ is preferred.

As a particularly preferred form of the fluorine-containing copolymer used in the present invention, general formula (3 ′) can be mentioned. In the general formula (3 ′), Rf ¹¹ , Rf ¹² , A, a, b, c, and d have the same meaning as in the general formula (3), and the preferred range is also the same.
General formula (3 ′):

In the general formula (3 ′), L ³¹ represents a divalent linking group, 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 of the linking group L ³¹ include * — (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 site on the hydroxyl side. For example).

(Preferred examples of each polymerization unit)
Although the preferable example of each polymerization unit in the perfluoro olefin copolymer used for this invention shown by the said general formula (3 ') below is shown, this invention is not limited to these.

  Specific examples of polymers useful in the present invention are shown in Table 2, but the present invention is not limited thereto. In Table 2, although expressed as a combination of polymerized units, the symbols, Q, N, M1, H and a to d in the table are all represented by the general formula (3 ′).

(Synthesis of fluorine-containing copolymer)
The fluorine-containing copolymer represented by the general formula (3) used in the present invention can be synthesized by various polymerization methods such as solution polymerization, precipitation polymerization, suspension polymerization, bulk polymerization, and emulsion polymerization. . Moreover, it is compoundable by well-known operations, such as a batch type, a semi-continuous type, and a continuous type.

  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, Each of various organic solvents such as methylene chloride, chloroform, dichloroethane, methanol, ethanol, 1-propanol, 2-propanol, and 1-butanol may be used alone or as a mixture of two or more kinds, or as a mixed solvent with water. Good.

  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 perform the polymerization in the range of 50 to 100 ° C. .

  The reaction pressure can be appropriately selected, but is usually 0.01 to 10 MPa, preferably 0.05 to 5 MPa, more preferably about 0.1 to 2 MPa. The reaction time is about 5 to 30 hours.

  The obtained polymer can be used as it is for the application of the present invention, or can be purified by reprecipitation or liquid separation operation.

(Curing agent (crosslinking agent))
The coating composition for the low refractive index layer used in the antireflection film of the present invention preferably contains a compound (curing agent) that can react with the hydroxyl group of the fluorine-containing copolymer and / or the polysiloxane-containing copolymer. . The curing agent preferably has two or more sites that react with a hydroxyl group, and more preferably has four or more sites. The structure of the curing agent is not particularly limited as long as it has the above number of functional groups capable of reacting with hydroxyl groups. For example, polyisocyanates, partial condensates of isocyanate compounds, multimers, polyhydric alcohols, low molecular weight polyester films And the like, block polyisocyanate compounds in which isocyanate groups are blocked with a blocking agent such as phenol, aminoplasts, polybasic acids or anhydrides thereof.

(Aminoplasts)
In the present invention, aminoplasts that can be particularly preferably used as the crosslinking agent are aminoplasts, and the aminoplasts are amino groups capable of reacting with hydroxyl groups present in the fluorine-containing copolymer, that is, hydroxyalkylamino groups or An alkoxyalkylamino group or a compound containing a carbon atom adjacent to a nitrogen atom and substituted with an alkoxy group. Specific examples include melamine compounds, urea compounds, benzoguanamine compounds, glycoluril compounds, and the like.

  The melamine compounds are generally known as compounds having a skeleton in which a nitrogen atom is bonded to a triazine ring, and specific examples include melamine, alkylated melamine, methylol melamine, and alkoxylated methyl melamine. . In particular, methylolated melamine and alkoxylated methyl melamine obtained by reacting melamine and formaldehyde under basic conditions and derivatives thereof are preferable, and alkoxylated methyl melamine is particularly preferable in view of storage stability. There are no particular restrictions on methylolated melamine and alkoxylated methylmelamine. For example, various resins obtained by the method described in Plastic Materials Course [8] Urea Melamine Resin (Nikkan Kogyo Shimbun) can be used. is there.

  In addition to urea, polymethylolated urea and derivatives thereof, alkoxylated methylurea, and compounds having a glycoluril skeleton and a 2-imidazolidinone skeleton having a cyclic urea structure are also preferable as the urea compound. As for the amino compounds such as the urea derivatives, various resins described in the above-mentioned “Yurea / Melamine resin” can be used.

As the amino compound used in the production of the coating liquid composition for a curable low refractive index layer used in the present invention, particularly from the viewpoint of compatibility with a fluorine-containing copolymer and a hydroxyl group-containing copolymer having a polysiloxane structure. Melamine compounds or glycoluril compounds are preferred, and alkoxymethylated melamine compounds or glycoluril compounds are more preferred due to their reactivity. Among them, the crosslinking agent is preferably a compound containing a nitrogen atom in the molecule and two or more carbon atoms substituted with an alkoxy group adjacent to the nitrogen atom. Particularly preferred compounds are compounds represented by the following structural formulas (H-1) and (H-2), and partial condensates thereof. In the formula, R represents an alkyl group having 1 to 6 carbon atoms or a hydroxyl group.
Structural formulas (H-1) and (H-2):

  The addition amount of aminoplast in the coating solution composition for the low refractive index layer is preferably 1 to 50 parts by mass per 100 parts by mass in total of the fluorine-containing copolymer and the hydroxyl group-containing copolymer having a polysiloxane structure. Is 3 to 40 parts by mass, and more preferably 5 to 30 parts by mass. If it is 1 part by mass or more, the durability as a thin film, which is a feature of the present invention, can be sufficiently exhibited, and if it is 50 parts by mass or less, it is a characteristic of the material of the present application when used for optical applications. This is preferable because a low refractive index can be maintained. From the viewpoint of keeping the refractive index low even when a curing agent is added, a curing agent that has a small increase in refractive index even when added is preferable, and from this viewpoint, the above compound has a skeleton represented by H-2. Compounds are more preferred.

(Curing catalyst)
Since the curing of the low refractive index layer in the present invention is accelerated by an acid catalyst, it is desirable to add an acidic substance. In order to achieve both storage stability and curing activity, it is more preferable to add a compound that generates an acid by heating (thermal acid generator) and / or a compound that generates an acid by light irradiation (photosensitive acid generator). .

(Thermal acid generator)
Thermal acid that can be blended in the curable coating composition for low refractive index layer (hereinafter also referred to as curable resin composition for low refractive index layer or simply curable resin composition) used in the present invention. The generator is a substance that can improve the heating conditions to be milder when the coating film of the curable resin composition is cured by heating.

  Specific examples of the thermal acid generator include, for example, various aliphatic sulfonic acids and salts thereof, various aliphatic carboxylic acids and salts thereof such as citric acid, acetic acid, and maleic acid, and various aromatic acids such as benzoic acid and phthalic acid. Examples thereof include carboxylic acids and salts thereof, alkylbenzene sulfonic acids and ammonium salts thereof, various metal salts, phosphoric acid and organic acid phosphoric esters.

  The use ratio of the thermal acid generator is preferably 0 to 10 parts by mass with respect to a total of 100 parts by mass of the fluorine-containing copolymer and the hydroxyl group-containing copolymer having a polysiloxane structure in the curable resin composition, More preferably, it is 0.1-5 mass parts. If this ratio is excessive, the storage stability of the curable resin composition becomes inferior, which is not preferable.

(Photosensitive acid generator)
The photosensitive acid generator that can be blended in the curable resin composition used in the present invention imparts photosensitivity to the coating film of the curable resin composition, for example, by irradiating radiation such as light. It is a substance that allows the coating film to be photocured.

Typical photosensitive acid generators include, for example, (1) various onium salts such as iodonium salt, sulfonium salt, phosphonium salt, diazonium salt, ammonium salt, pyridinium salt; (2) β-ketoester, β-sulfonylsulfone And sulfone compounds such as α-diazo compounds; (3) sulfonate esters such as alkyl sulfonate, haloalkyl sulfonate, aryl sulfonate, and imino sulfonate; (4) represented by the following general formula (5) (5) diazomethane compounds represented by the following general formula (6); and the like.
General formula (5):

In the formula, U ⁵¹ represents a divalent group such as an alkylene group, an arylene group, or an alkoxylen group, and R ⁵¹ represents a monovalent group such as an alkyl group, an aryl group, a halogen-substituted alkyl group, or a halogen-substituted aryl group. Indicates.

  General formula (6):

In the formula, R ⁶¹ and R ⁶² may be the same as or different from each other, and each represents a monovalent group such as an alkyl group, an aryl group, a halogen-substituted alkyl group, or a halogen-substituted aryl group.

The photosensitive acid generator can be used alone or in combination of two or more, and can also be used in combination with the thermal acid generator. The use ratio of the photosensitive acid generator is preferably 0 to 20 parts by mass with respect to 100 parts by mass in total of the fluorine-containing copolymer and the hydroxyl group-containing copolymer having a polysiloxane structure in the curable resin composition, More preferably, it is 0.1-10 mass parts. If this ratio is less than or equal to the upper limit value, it is preferable because the cured film obtained has excellent strength and good transparency.

  The low refractive index layer in the present invention is a curable resin composition containing at least two types of copolymers, that is, a fluorine-containing copolymer and a hydroxyl group-containing copolymer having a polysiloxane structure, a curing agent, and a curing catalyst. It is also preferable that the product further contains inorganic fine particles and an organosilane compound described later.

(Inorganic fine particles for low refractive index layer)
The amount of the inorganic fine particles to a low refractive index layer is preferably 1 to 100 mg / m ^2, more preferably 5-80 mg / m ^2, more preferably from 10~60mg / m ^2. If the blending amount of the inorganic fine particles is equal to or higher than the lower limit value, the effect of improving the scratch resistance is remarkable, and if it is equal to or lower than the upper limit value, fine irregularities are formed on the surface of the low refractive index layer, black tightening, etc. Therefore, it is preferable to be within the above-mentioned range.

  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 size of these inorganic fine particles is preferably 1 to 200 nm, more preferably 5 to 90 nm. If the particle size of the inorganic fine particle is equal to or greater than the lower limit, the effect of improving the scratch resistance is increased. If the particle size is equal to or smaller than the upper limit, fine irregularities are formed on the surface of the low refractive index layer, and black tightening, etc. Therefore, it is preferable to be within the above-mentioned range.

  The inorganic 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.

(Organosilane compound)
In the present invention, the low refractive index layer may be formed from a curable resin composition further containing an organosilane compound. The definition of the organosilane compound, the structure of the preferred compound, and the like are the same as those described in [0137] to [0138] of JP-A-2004-331812.

(Other additives)
The curable resin composition that is the coating liquid composition for the low refractive index layer in the present invention includes at least the above-mentioned fluorine-containing copolymer and a hydroxyl group-containing copolymer having a polysiloxane structure, and a curing agent as necessary. In addition to the curing catalyst, the inorganic fine particles and the organosilane compound, various additives, a radical polymerization initiator and a cationic polymerization initiator are added, and these are dissolved in an appropriate solvent. At this time, the concentration of the solid content is appropriately selected depending on the application, but is generally about 0.01 to 60% by mass, preferably 0.5 to 50% by mass, particularly preferably 1 to 20% by mass. %.

From the viewpoint of interfacial adhesion between the lower refractive index layer and the lower layer that is in direct contact, a curing agent such as a polyfunctional (meth) acrylate compound, polyfunctional epoxy compound, polyisocyanate compound, aminoplast, polybasic acid, or an anhydride thereof. Can also be added in small amounts. When adding these, it is preferable to set it as the range of 30 mass% or less with respect to the total solid of a low-refractive-index layer film, It is more preferable to set it as the range of 20 mass% or less, The range of 10 mass% or less It is particularly preferable that

  Further, for the purpose of imparting properties such as antifouling property, water resistance, chemical resistance and slipping property, other than the above organosilane compounds, known silicone compound or fluorine compound antifouling agents, slipping agents and the like are appropriately used. It can also be added. When these additives are added, it is preferably added in the range of 0.01 to 20% by mass, more preferably in the range of 0.05 to 10% by mass of the total solid content of the low refractive index layer. Particularly preferably 0.1 to 5% by mass.

(Silicone compound)
Preferable examples of the silicone compound include those having a substituent at the terminal and / or side chain of the compound 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. It is done.

  The molecular weight of the silicone compound is not particularly limited, but is preferably 100,000 or less, particularly preferably 50,000 or less, and most preferably 3,000 to 30,000.

  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. Most preferably, it is 0 mass%.

  Examples of preferable silicone compounds include "X-22-174DX", "X-22-2426", "X-22-164B", "X22-164C", "X-" manufactured by Shin-Etsu Chemical Co., Ltd. 22-170DX "," X-22-176D "," X-22-1821 "(named above);" FM-0725 "," FM-7725 "," FM-4421 ", manufactured by Chisso Corporation “FM-5521”, “FM-6621”, “FM-1121”; “DMS-U22”, “RMS-033”, “RMS-083”, “UMS-182”, “DMS-H21” manufactured by Gelest, Examples thereof include, but are not limited to, “DMS-H31”, “HMS-301”, “FMS121”, “FMS123”, “FMS131”, “FMS141”, and “FMS221” (named above).

(Fluorine compounds)
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 ₃ (CF ₃ ) ₄ H, —CH ₂ (CF ₂ ) ₈ CF ₃ , —CH ₂ CH ₂ (CF ₂ ) ₄ H, etc.}, 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, -CH 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.

  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 polymer or an 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 in 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 "R-2020", "M-2020", "R-3833", "M-3833" (trade names) manufactured by Daikin Industries, Ltd .; Dainippon Ink and Chemicals, Inc. “Megafuck F-171”, “Megafuck F-172”, “Megafuck F-179A”, “Defenser MCF-300” (named above) are available, but are not limited to these. It is not something.

  (Dustproofing agent, antistatic agent, etc.) For the purpose of imparting properties such as dustproofing and antistatic properties to the curable resin composition for forming the low refractive index layer, further known cationic surfactants or polyoxyalkylenes A dustproof agent, an antistatic agent or the like such as a compound may be added as appropriate. As for these dustproof agent and antistatic agent, the structural unit may be included in the silicone-based compound or the fluorine-based compound as a part of the function.

  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 preferably 0.1 to 5% by mass.

  Examples of preferred compounds include “Megafac F-150” (trade name) manufactured by Dainippon Ink & Chemicals, Inc., “SH-3748” (trade name) manufactured by Toray Dow Corning Co., Ltd. However, it is not limited to these.

(Solvent for coating low refractive index layer)
In the present invention, as the solvent used in the coating liquid composition for forming the low refractive index layer, each component can be dissolved or dispersed, and it is easy to form a uniform surface in the coating process and the drying process. Various solvents selected from the viewpoints of ensuring storage stability and having an appropriate saturated vapor pressure can be used. From the viewpoint of low load on drying, it is preferable to use a solvent having a boiling point of 100 ° C. or lower at normal pressure and room temperature, and a small amount of solvent having a boiling point of 100 ° C. or higher for adjusting the drying speed. .

Examples of the solvent having a boiling point of 100 ° C. or lower include hydrocarbons such as hexane (boiling point 68.7 ° C.), heptane (98.4 ° C.), cyclohexane (80.7 ° C.), benzene (80.1 ° C.), Halogenated carbonization such as dichloromethane (39.8 ° C), chloroform (61.2 ° C), carbon tetrachloride (76.8 ° C), 1,2-dichloroethane (83.5 ° C), trichloroethylene (87.2 ° C) Hydrogens, diethyl ether (34.6 ° C), diisopropyl ether (68.5 ° C), dipropyl ether (90.5 ° C), ethers such as tetrahydrofuran (66 ° C), ethyl formate (54.2 ° C), Esters such as methyl acetate (57.8 ° C.), ethyl acetate (77.1 ° C.), isopropyl acetate (89 ° C.), acetone (56.1 ° C.), 2-butanone (methyl ethyl) Ketones such as Luketone, 79.6 ° C, methanol (64.5 ° C), ethanol (78.3 ° C), 2-propanol (82.4 ° C), 1-propanol (97.2 ° C), etc. Alcohols, cyano compounds such as acetonitrile (81.6 ° C.), propionitrile (97.4 ° C.), carbon disulfide (46.2 ° C.), and the like. Of these, ketones and esters are preferable, and ketones are particularly preferable. Among the ketones, 2-butanone is particularly preferable.

  Examples of the solvent having a boiling point of 100 ° C. or more include, for example, octane (125.7 ° C.), toluene (110.6 ° C.), xylene (138 ° C.), tetrachloroethylene (121.2 ° C.), and chlorobenzene (131.7 ° C.). , Dioxane (101.3 ° C.), dibutyl ether (142.4 ° C.), isobutyl acetate (118 ° C.), cyclohexanone (155.7 ° C.), 2-methyl-4-pentanone {same as methyl isobutyl ketone (MIBK), 115.9 ° C.}, 1-butanol (117.7 ° C.), N, N-dimethylformamide (153 ° C.), N, N-dimethylacetamide (166 ° C.), dimethyl sulfoxide (189 ° C.) and the like. Cyclohexanone and 2-methyl-4-pentanone are preferable.

[Layer structure of optical film]
The antireflection film of the present invention has a hard coat layer, which will be described later, on a transparent substrate, if necessary, and has a refractive index, a film thickness, and the number of layers so that the reflectance decreases due to optical interference. The layers are laminated in consideration of the layer order and the like.

  In the simplest configuration, the low-reflection antireflection film has a configuration in which only a low refractive index layer is coated on a substrate. In order to further reduce the reflectance, the antireflection layer is preferably constituted by combining a high refractive index layer having a higher refractive index than that of the base material and a low refractive index layer having a lower refractive index than that of the base material. Examples of configurations include two layers of a high refractive index layer / low refractive index layer from the base material side, and three layers having different refractive indices, a medium refractive index layer (having a higher refractive index than the base material or the hard coat layer). , A layer having a refractive index lower than that of a high refractive index layer) / a layer having a high refractive index / a layer having a low refractive index, and the like.

The example of the preferable layer structure of the antireflection film of this invention is shown below. In the following configuration, the base film functions as a support.
・ Base film / low refractive index layer,
・ Base film / Antistatic layer / Low refractive index layer,
・ Base film / Anti-glare layer / Low refractive index layer,
Base film / antiglare layer / antistatic layer / low refractive index layer,
Base film / antistatic layer / antiglare layer / low refractive index layer,
・ Base film / hard coat layer / antiglare layer / low refractive index layer,
・ Base film / hard coat layer / antiglare layer / antistatic layer / low refractive index layer,
・ Base film / hard coat layer / antistatic layer / antiglare layer / low refractive index layer,
・ Base film / hard coat layer / high refractive index layer / low refractive index layer,
・ Base film / hard coat layer / antistatic layer / high refractive index layer / low refractive index layer,
Base film / hard coat layer / medium refractive index layer / high refractive index layer / low refractive index layer,
Base film / antiglare layer / high refractive index layer / low refractive index layer,
Base film / antiglare layer / medium refractive index layer / high refractive index layer / low refractive index layer,
Base film / antistatic layer / hard coat layer / medium refractive index layer / high refractive index layer / low refractive index layer,
Antistatic layer / base film / hard coat layer / medium refractive index layer / high refractive index layer / low refractive index layer,
Base film / antistatic layer / antiglare layer / medium refractive index layer / high refractive index layer / low refractive index layer,
Antistatic layer / base film / antiglare layer / medium refractive index layer / high refractive index layer / low refractive index layer,
Antistatic layer / base film / antiglare layer / high refractive index layer / low refractive index layer / high refractive index layer / low refractive index layer.

  As long as the reflectance can be reduced by optical interference, it is not limited to these layer configurations. The high refractive index layer may be a light diffusing layer having no antiglare property. The antistatic layer is preferably a layer containing conductive polymer particles or metal oxide fine particles (for example, ATO, ITO), and can be provided by coating or atmospheric pressure plasma treatment.

[Layers other than low refractive index layer]
[Film-forming binder]
In the present invention, as the main film-forming binder component of the film-forming composition for forming a layer other than the low refractive index layer, it is possible to use a compound having an ethylenically unsaturated group to improve film strength, coating solution stability, coating It is preferable in terms of membrane productivity. The main film-forming binder refers to one that accounts for 10% by mass or more of the film-forming components excluding inorganic particles. Preferably, they are 20 mass% or more and 100 mass% or less, More preferably, they are 30 mass% or more and 95% or less.

  A polymer having a saturated hydrocarbon chain or a polyether chain as a main chain is preferable, and a polymer having a saturated hydrocarbon chain as a main chain is more 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 make the formed film have a high refractive index, the monomer structure contains an aromatic ring, at least one atom selected from halogen atoms other than fluorine, sulfur atoms, phosphorus atoms, and nitrogen atoms. It is preferable.

  Examples of the monomer having two or more ethylenically unsaturated groups include esters of polyhydric alcohol and (meth) acrylic acid {for example, ethylene glycol di (meth) acrylate, 1,4-cyclohexanediacrylate, pentaerythritol tetra ( (Meth) acrylate, pentaerythritol tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolethane tri (meth) acrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipenta Erythritol hexa (meth) acrylate, pentaerythritol hexa (meth) acrylate, 1,2,3-cyclohexanetetramethacrylate, polyurethane polyacrylate, polyester Acrylate, etc.}, vinylbenzene and derivatives thereof (for example, 1,4-divinylbenzene, 4-vinylbenzoic acid-2-acryloylethyl ester, 1,4-divinylcyclohexanone, etc.), vinylsulfone (for example, divinylsulfone), acrylamide (For example, methylenebisacrylamide) and methacrylamide. Two or more of these monomers may be used in combination. In the present specification, “(meth) acrylate” represents “acrylate or methacrylate”.

  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 these monomers 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.

  As radical photopolymerization initiators, acetophenones, benzoins, benzophenones, phosphine oxides, ketals, anthraquinones, thioxanthones, azo compounds, peroxides, 2,3-dialkyldione compounds, disulfide compounds And fluoroamine compounds and aromatic sulfoniums.

  Examples of acetophenones include 2,2-diethoxyacetophenone, p-dimethylacetophenone, 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-dichlorobenzophenone, 4,4-dichlorobenzophenone and p-chlorobenzophenone. Examples of phosphine oxides include 2,4,6-trimethylbenzoyldiphenylphosphine oxide.

  In addition, P. of “Latest UV Curing Technology”. Various examples are also described in 159 {Issuer: Kazuhiro Takasato, Issuer; 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 Ciba Specialty Chemicals.

  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-azobisisobutyronitrile, 2-azobispropionitrile, 2-azobiscyclohexanedinitrile, etc. as azo compounds, diazoaminobenzene, p-nitrobenzenediazonium, etc. as diazo compounds be able to.

  The thermal radical initiator is preferably used in the range of 0.1 to 15 parts by mass, more preferably in the range of 1 to 10 parts by mass with respect to 100 parts by mass of the polyfunctional monomer.

  In the present invention, a polymer having a polyether as a main chain can also be used. A ring-opening polymer of a polyfunctional epoxy compound is preferred. The ring-opening polymerization of the polyfunctional epoxy compound can be performed by irradiation with ionizing radiation or heating in the presence of a photosensitive acid generator or a thermal acid generator.

  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 this crosslinkable functional group reacts. A crosslinked structure may be introduced into the binder polymer.

Examples of the crosslinkable functional group include an isocyanate group, an epoxy group, an aziridine group, an oxazoline group, an aldehyde group, a carbonyl group, a hydrazine group, a carboxyl group, a methylol group, and an 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.

[Hard coat layer]
(Material for hard coat layer)
In the present invention, it is preferable to provide a hard coat layer. The hard coat layer can be formed from a binder and, if necessary, mat particles for imparting antiglare properties, and an inorganic filler for increasing the refractive index, preventing crosslinking shrinkage, and increasing the strength.

(Matte particles)
In the hard coat layer, for the purpose of imparting antiglare properties, mat particles having an average particle size of 0.1 to 5.0 μm, preferably 1.5 to 3.5 μm, such as inorganic compound particles or larger than filler particles. Resin particles can be contained.

  If the difference in refractive index between the matte particles and the binder is too large, the film becomes cloudy, and if it is too small, a sufficient light diffusion effect cannot be obtained, so 0.02 to 0.20 is preferable, and 0.04 to Particularly preferred is 0.10. Similarly to the refractive index, the amount of addition of the matting particles to the binder is too large, the film becomes cloudy, and if it is too small, a sufficient light diffusion effect cannot be obtained. % Is particularly preferred.

As specific examples of the mat particles, inorganic particles 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 different kinds of mat particles may be used in combination. When two or more kinds of mat particles are used, the difference in refractive index is preferably 0.02 or more and 0.10 or less in order to effectively exert the refractive index control by mixing the two, and 0.03 or more. Is particularly preferably 0.07 or less. Further, it is possible to impart an antiglare property with mat particles having a larger particle size and to impart another optical characteristic 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.

Further, 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 hard coat layer so that the amount of the mat particles in the formed hard coat layer is preferably 10 to 1000 mg / m ² , more preferably 100 to 700 mg / m ² .

  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.

(Inorganic filler)
The hard coat layer has at least one selected from titanium, zirconium, aluminum, indium, zinc, tin, and antimony, in addition to the above mat particles, in order to increase the refractive index of the layer and to reduce curing shrinkage. It is preferable to contain an inorganic filler made of one kind of metal 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.

  In order to increase the difference in refractive index from the mat particles, it is also preferable to use a silicon oxide in the hard coat layer using the high refractive index mat particles in order to keep the refractive index of the layer low. The preferred particle size is the same as that of the inorganic filler.

Specific examples of the inorganic filler used in the hard coat layer include TiO ₂ , ZrO ₂ , Al ₂ O ₃ , In ₂ O ₃ , ZnO, SnO ₂ , Sb ₂ O ₃ , ITO, SiO _{2 and the} like. TiO ₂ and ZrO ₂ are particularly preferable in terms 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 hard coat layer, more preferably 20 to 80%, and particularly preferably 30 to 70%.

  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 hard coat layer in 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 this range, the type 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 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 within this range, good antiglare properties and antireflection properties can be obtained without causing deterioration of the transmitted image.

[Support]
As the transparent support of the antireflection film of the present invention, a plastic film is preferably used. Examples of the polymer forming the plastic film include cellulose esters {eg, triacetyl cellulose, diacetyl cellulose, typically “TAC-TD80U”, “TAC-TD80UF”, etc., manufactured by Fuji Photo Film Co., Ltd.}, polyamide, polycarbonate, Polyester (for example, polyethylene terephthalate, polyethylene naphthalate, etc.), polystyrene, polyolefin, norbornene resin {“Arton” (trade name), manufactured by JSR Corporation}, amorphous polyolefin {“ZEONEX” (trade name), Japan ZEON Co., Ltd.}. Of these, triacetyl cellulose, polyethylene terephthalate, and polyethylene naphthalate are preferable, and triacetyl cellulose is particularly preferable.

  In addition, a cellulose acylate film substantially free of halogenated hydrocarbons such as dichloromethane and a method for producing the same are disclosed in JIII Journal of Technical Disclosure No. 2001-1745, published on March 15, 2001, the following. The cellulose acylate described here is also preferably used in the present invention.

[Saponification]
When the antireflection film of the present invention is used in an image display device, it is disposed on the outermost surface of the display by providing an adhesive layer on one side. When the transparent support of the antireflection film is triacetylcellulose, since triacetylcellulose is used as a protective film for protecting the polarizing film of the polarizing plate, it is costly to use the antireflection film of the present invention as it is for the protective film. Preferred above.

  The antireflective film of the present invention is a transparent support in order to sufficiently adhere it when it is disposed on the outermost surface of a display by providing an adhesive layer on one side or used as it is as a protective film for a polarizing plate. It is preferable to carry out a saponification treatment after forming an outermost layer mainly composed of a hydroxyl group-containing copolymer having a polysiloxane structure and a fluorine-containing copolymer.

  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 alkali solution, it is preferable to sufficiently wash with water so that the alkali component does not remain in the film, and to soak in a dilute acid to neutralize the alkali component. 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 polarizing 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 when adhering to the polarizing film, it is difficult for dust to enter between the polarizing film and the antireflective film, thus preventing point defects due to dust. It is effective for.

  The saponification treatment is preferably carried out so that the contact angle of water on the surface of the transparent support on the side 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 triacetyl cellulose 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 forming the antireflection layer on the transparent support, an alkaline solution is applied to the surface of the antireflection film opposite to the surface on which the antireflection layer is formed, and is heated, washed and / or neutralized. By doing so, only the back surface of the film is saponified.

[Coating film forming method]
The antireflection 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. The coating solution is applied on the transparent support by the dip coating method, air knife coating method, curtain coating method, roller coating method, wire bar coating method, gravure coating method, extrusion coating method (see US Pat. No. 2,681,294). Apply, heat and dry.

  Among these coating methods, the gravure coating method is preferable 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 is more preferable because of high film thickness uniformity.

  Even with the die coating method, it is possible to apply a coating solution with a small coating amount with high film thickness uniformity, and the die coating method is a pre-weighing method, so that the film thickness can be controlled relatively easily. This is preferable because of less evaporation of the solvent.

  In the antireflection film consisting of a plurality of layers, two or more layers may be applied simultaneously. For the method of simultaneous application, US Pat. Nos. 2,761,791, 2,941,898, 3,508,947, 3,526,528, and Harasaki Yuji, “Coating Engineering”, page 253, {Asakura Shoten (1973)}.

<Use of antireflection film>
〔Polarizer〕
The polarizing plate is mainly composed of two protective films that sandwich the polarizing film from both sides. The antireflection film of the present invention 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.

[Polarizing film]
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 in which the absorption axis of the polarizing film is neither parallel nor perpendicular to the longitudinal direction is produced by the following method. That is, both ends of a continuously supplied polymer film are stretched by applying a tension while being held by a holding means and stretched at least 1.1 to 20.0 times in the film width direction. The longitudinal movement speed difference of the holding device is within 3%, and the angle formed by the film traveling 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 °. It can be produced by a stretching method in which the traveling direction is bent with both ends of the film held. In particular, those inclined at 45 ° are preferably used from the viewpoint of productivity.

  The method for stretching the polymer film is described in detail in paragraphs 0020 to 0030 of JP-A-2002-86554.

(Image display device)
The image display device of the present invention uses the antireflection film or the polarizing plate on the outermost surface of the display. For example, in the aspect used as one side of the surface protective film of the polarizing film, twisted nematic (TN), super twisted nematic (STN), vertical alignment (VA), in-plane switching (IPS), optically compensated bend It can be preferably used for a transmissive, reflective, or transflective liquid crystal display device in a mode such as a cell (OCB).

In VA mode liquid crystal cell,
(1) In addition to a narrowly-defined VA mode liquid crystal cell (described in JP-A-2-176625) in which rod-like liquid crystalline molecules are aligned substantially vertically when no voltage is applied, and substantially horizontally when a voltage is applied. ,
(2) Liquid crystal cell ("SID97, Digest of tech. Papers" (Preliminary Collection), Vol. 28 (1997), p. 845},
(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 (Procedures 58-59 (1998) ) Description) and
(4) Includes SURVAVAL mode liquid crystal cells (announced at "LCD International 98").

  For a VA mode liquid crystal cell, a polarizing plate prepared by combining a biaxially stretched triacetyl cellulose film with the antireflection film of the present invention is preferably used. As for the method for producing a biaxially stretched triacetyl cellulose film, for example, the methods described in JP-A Nos. 2001-249223 and 2003-170492 are preferably used.

  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. 4,583,825 and 5,410,422. 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.

  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” {issued by Toray Research Center (2001)}.

  In particular, for a TN mode or IPS mode liquid crystal display device, as described in Japanese Patent Application Laid-Open No. 2001-100043, an optical compensation film having an effect of widening the viewing angle is protected on the two sides of the polarizing film. By using it on the surface of the film opposite to the antireflection film of the present invention, a polarizing plate having an antireflection effect and a viewing angle expansion effect can be obtained with the thickness of one polarizing plate, which is particularly preferable.

  The present invention will be further described below based on examples, but the present invention is not limited thereto. In the following Examples and Synthesis Examples,% represents mass% unless otherwise specified.

<Preparation of antireflection film>
[Synthesis of a hydroxyl group-containing copolymer having a polysiloxane structure]
Synthesis Example 1: Synthesis of (P-1) 10 g of methyl ethyl ketone was placed in a three-necked flask having an internal volume of 200 mL, and the temperature was raised to 80 ° C while stirring. After sufficiently substituting the inside of the flask with nitrogen, the polymer initiator “VPS-1001” having a polysiloxane structure of the above structural formula {S- (1)} {manufactured by Wako Pure Chemical Industries, Ltd.} 10.0 g Then, a mixed solution of 0.5 g of hydroxyethyl methacrylate (HEMA) and 30 g of methyl ethyl ketone was added dropwise in 3 hours with a chemical pump while stirring. After dropping, the mixture was further stirred for 5 hours and cooled to room temperature. The polymerization solution was poured into a mixed solvent of water / methanol = 400 mL / 40 mL to precipitate a polymer, followed by vacuum drying at 50 ° C. to 8.5 g of a hydroxyl group-containing copolymer having a polysiloxane structure (P -1) was obtained. The obtained polymer had a mass average molecular weight of 38,000.

Synthesis Examples 2 to 7: Synthesis of (P-2), (P-3), (P-5), (P-9), (P-17), and (P-19) (P- in Synthesis Example 1) (P-2), (P-3), (P-5), (P-9), (P-17) and (P-19) were synthesized in substantially the same manner as in the synthesis of 1). The mole fraction (mol%) and mass average molecular weight of each polymerized unit are as shown in Table 1 above.

[Synthesis of fluorinated copolymer]
Synthesis Example 11: Synthesis of (T-1) A 100 mL stainless steel autoclave with a stirrer was charged with 40 ml of ethyl acetate, 14.7 g of hydroxyethyl vinyl ether (HEVE) and 0.55 g of dilauroyl peroxide, and the system was removed. 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 precipitated polymer was taken out by removing the solvent by decantation. Further, this polymer was dissolved in a small amount of ethyl acetate, and the remaining monomer was completely removed by reprecipitation from hexane twice. After drying, 28 g of a fluorine-containing copolymer (T-1) having a molar ratio of 1: 1 of hexafluoropropylene and hydroxyethyl vinyl ether was obtained. The weight average molecular weight of the obtained polymer was 25,000.

Synthesis Examples 12 to 4: Synthesis of (T-2), (T-4), (T-5), and (T-8) In substantially the same manner as the synthesis of (T-1) in Synthesis Example 11, (T -2), (T-4), (T-5) and (T-8) were synthesized. The mole fraction (mol%) and the mass average molecular weight of each constituent component are as shown in Table 2 above.

Comparative Synthesis Example 1: Synthesis of Comparative Copolymer (U-1) Under the same conditions as in Synthesis Example 11, 0.6 g of a polymer initiator “VPS-1001” was further added and polymerization was performed to obtain a polysiloxane structure. The following comparative copolymer (U-1) was introduced, in which 2% by mass of a copolymer moiety having a thiophene content was introduced. The weight average molecular weight of the obtained polymer was 60,000.
Comparative copolymer (U-1):

Comparative Synthesis Example 2: Synthesis of Comparative Copolymer (U-2) In an autoclave with a stainless steel stirrer having an internal volume of 100 mL, 40 mL of ethyl acetate and 2.20 g of HEVE, the above structural formula {S- (1)} A polymer initiator having a polysiloxane structure “VPS-1001” {manufactured by Wako Pure Chemical Industries, Ltd.} 12.92 g and dilauroyl peroxide 0.40 g were charged, and the system was deaerated and replaced with nitrogen gas. Further, 4.2 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 4.4 kg / cm ² . The temperature was kept at 65 ° C., and the reaction was continued for 10 hours. When the pressure reached 2.2 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 reaction solution was poured into a large excess of methanol, and the resulting polymer was dissolved in a small amount of ethyl acetate and reprecipitated twice to completely remove residual monomers. The polymer was dried under reduced pressure to obtain a fluorine-containing copolymer (U-2) having a polysiloxane segment. The obtained polymer had a mass average molecular weight of 31,000.
Comparative copolymer (U-2)

[Preparation of antireflection film]
Examples 1-1 to 1-20 and Comparative Examples 1-1 to 1-5
[Preparation of coating solutions for low refractive index layer (Ln-1 to Ln-20)]
Each component shown in Table 3 was mixed and dissolved in 2-butanone to prepare a composition for forming a low refractive index layer having a solid content of 6% by mass. The numbers in parentheses in Table 3 represent parts by mass of the solid content of each component.

  In Table 3, colloidal silica represents “MEK-ST” manufactured by Nissan Chemical Industries, Ltd., CY303 represents “Cymel 303”, and methylolated melamine manufactured by Nippon Cytec Industries, Ltd. H-11 and H-21 each represent a compound having the following structure. PTS represents p-toluenesulfonic acid monohydrate.

[Preparation of Comparative Refractive Index Layer Coating Liquids (Lnr-1 to Lnr-5)]
In the same manner as in the example of the coating solution for the low refractive index layer, each component shown in Table 4 was mixed and dissolved in 2-butanone to prepare a coating solution for the comparative low refractive index layer having a solid content of 6%. . The values in parentheses in Table 4 represent parts by mass of the solid content of each component, and the meanings of the abbreviations are as described above.

[Preparation of composition for forming hard coat layer (HC-1)]
"PET-30" 50.0g
"Irgacure 184" 2.0g
"SX-350" (30% by mass) 1.5g
Cross-linked acrylic-styrene particles (30% by mass) 13.9 g
"KBM-5103" 10.0g
Toluene 38.5g

  The above mixed solution was filtered through a polypropylene filter having a pore size of 30 μm to prepare a composition for forming a hard coat layer (HC-1).

The compounds used are shown below.
“PET-30”: mixture of pentaerythritol triacrylate and pentaerythritol tetraacrylate {manufactured by Nippon Kayaku Co., Ltd.}
“Irgacure 184”: Polymerization initiator {Ciba Specialty Chemicals Co., Ltd.}
“SX-350”: Cross-linked polystyrene particles having an average particle size of 3.5 μm {refractive index 1.60, manufactured by Soken Chemical Co., Ltd., 30% by mass toluene dispersion. Use after dispersion for 20 minutes at 10,000 rpm in a Polytron disperser}.
Cross-linked acrylic-styrene particles: average particle size 3.5 μm {refractive index 1.55, manufactured by Soken Chemical Co., Ltd., 30% by mass toluene dispersion. Use after dispersion for 20 minutes at 10,000 rpm in a Polytron disperser}.
“KBM-5103”: acryloyloxypropyltrimethoxysilane {manufactured by Shin-Etsu Chemical Co., Ltd.}.

[Preparation of antireflection film]
An 80 μm-thick triacetyl cellulose film “TAC-TD80U” {manufactured by Fuji Photo Film Co., Ltd.} is unrolled in a roll form, and the above hard coat layer forming composition (HC-1) is directly Using a gravure roll with a diameter of 180 mm / in and a gravure pattern with a depth of 40 μm and a doctor blade, a gravure roll was applied at a rotation speed of 30 rpm and a conveyance speed of 30 m / min. after drying, further by using "air-cooled Metal halide lamp" {manufactured by eye graphics Co., Ltd.} of 160 W / cm at an oxygen concentration of 0.1 vol% nitrogen purge, illuminance 400 mW / cm ^2, irradiation amount 110 mJ / cm ² The ultraviolet ray was irradiated to cure the coating layer, and a 6 μm thick layer was formed and wound up. The surface roughness of the hard coat layer obtained in this manner was Ra = 0.18 μm, Rz = 1.40 μm, and haze 35%.

On the hard coat layer thus obtained, the low refractive index layer film thickness is 95 nm using the composition for forming a low refractive index layer (present inventions Ln1 to 20 and comparative examples Lnr1 to 5). Thus, antireflection films (101) to (120) and (R01) to (R05) were prepared. The low refractive index layer was dried at 120 ° C. for 10 minutes, and the ultraviolet curing condition was an “air-cooled metal halide lamp” of 240 W / cm while purging with nitrogen so that the atmosphere had an oxygen concentration of 0.01% by volume or less. Using an iGraphics Co., Ltd.}, an illuminance of 120 mW / cm ² and an irradiation amount of 240 mJ / cm ² was used. Table 5 shows combinations of the hard coat layer forming composition and the low refractive index layer forming composition used for each of the obtained antireflection films.

[Saponification treatment of antireflection film]
The obtained antireflection film was treated and dried under the following saponification standard conditions.
(1) Alkaline bath: 1.5 mol / L sodium hydroxide aqueous solution, 55 ° C.-120 seconds (2) First washing bath: tap water, 60 seconds (3) Neutralization bath: 0.05 mol / L sulfuric acid, 30 ° C. -20 seconds (4) Second water washing bath: tap water, 60 seconds (5) Drying: 120 ° C.-60 seconds

[Evaluation of antireflection film]
The following evaluation was performed using the saponified antireflection film thus obtained. The results obtained are shown in Table 5.

(Evaluation 1) Measurement of average reflectance Using a spectrophotometer "V-550" {manufactured by JASCO Corporation}, spectral reflectance at an incident angle of 5 ° using an integrating sphere in a wavelength range of 380 to 780 nm. Was measured. In the evaluation of the spectral reflectance, an average reflectance of 450 to 650 nm was used.
The measurement was performed on a black table after roughening the back surface of the antireflection film, followed by light absorption treatment with black ink (transmittance at 380 to 780 nm of less than 10%).

(Evaluation 2) Scratch resistance (1)-Steel wool resistance evaluation A rubbing test was performed using a rubbing tester under the following conditions.
Evaluation environmental conditions: 25 ° C., 60% RH,
Rub material: Steel wool “No. 0000” {manufactured by Nippon Steel Wool Co., Ltd.} 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. Then, the reciprocating rubbing motion under the following conditions was given.
Moving distance (one way): 13 cm, rubbing speed: 13 cm / second,
Load: 200 g / cm ²
Tip contact area: 1 cm × 1 cm,
Number of rubs: 10 round trips.
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.
○: Even when viewed very carefully, no scratches are visible.
○ △: Slightly weak scratches are visible when viewed very carefully.
Δ: A weak scratch is visible.
Δ ×: moderate scratches are visible.
X: There are scratches that can be seen at first glance.

(Evaluation 3) Scratch resistance (2) -Eraser rubbing resistance evaluation A rubbing test was conducted using a rubbing tester under the following conditions.
Evaluation environmental conditions: 25 ° C., 60% RH
Rubbing material: A plastic eraser {"MONO" manufactured by Dragonfly Pencil Co., Ltd.) was fixed to the tip (1 cm x 1 cm) of the rubbing of the tester in contact with the sample.
Moving distance (one way): 4 cm, rubbing speed: 2 cm / sec, load: 500 g / cm ² , tip contact area: 1 cm × 1 cm,
Number of rubs: 100 round trips.
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.
○: Even when viewed very carefully, no scratches are visible.
○ △: Slightly weak scratches are visible when viewed very carefully.
Δ: A weak scratch is visible.
Δ ×: moderate scratches are visible.
X: There are scratches that can be seen at first glance.
XX: Single-sided film is damaged.

(Evaluation 4) “Magic ink” adhesion evaluation As an index of surface contamination resistance, the optical material was conditioned at a temperature of 25 ° C. and a humidity of 60% RH for 2 hours, and then “magic ink” (trade name) was applied to the sample surface. After adhering, the state when it was wiped off with a cleaning cloth was observed, and the “magic ink” adhesion was evaluated as follows.
A: The mark of “magic ink” can be completely wiped off.
○: A trace of “magic ink” is visible.
Δ: A trace of “magic ink” is visible.
X: Traces of “magic ink” are hardly wiped off.

As is apparent from this example, the antireflection film of the present invention has a very low surface reflectance, a sufficiently strong film strength, and excellent antifouling properties. In addition, since the antireflection film of the present invention contains the polysiloxane-containing copolymer of the present invention that is excellent in surface uneven distribution, the antifouling property compared to the comparative examples (film Nos. R01, R02, R03, R04, R05). Is excellent.
Moreover, since the antireflection film of the present invention has a high hydroxyl group content, it is excellent in scratch resistance as compared with Comparative Examples (film Nos. R01, R02, R04, R05).

<Production of image display device>
Examples 2-1 to 2-20 and comparative examples 2-1 to 2-5
The antireflection films (film Nos. 101 to 120 and R01 to R05) prepared in the above examples and comparative examples were attached to the surface of a liquid crystal display of a personal computer “PC9821NS / 340W” obtained from NEC Corporation. A surface device sample was prepared, and the degree of landscape reflection due to the surface reflection was visually evaluated.

  The image display apparatus provided with the antireflection film (film Nos. 101 to 120) according to the embodiment of the present invention has almost no reflection of the surrounding scenery, exhibits comfortable visibility, and has sufficient surface strength. On the other hand, the image display device provided with the antireflection film (film Nos. R01 to R05) of the comparative example was inferior in surface strength although the surrounding reflection could be reduced to some extent.

FIG. 1 is a schematic cross-sectional view showing a layer structure when the antireflection film of the present invention is a composite film. FIG. 1A shows an example of a four-layer structure, and FIG.

Explanation of symbols

1a: Antireflection film 1b: Antireflection film 2: Transparent support 3: Hard coat layer 4: High refractive index layer 5: Low refractive index layer (outermost layer)
6: Medium refractive index layer

Claims (7)

Component having a polysiloxane structure represented by the following general formula (1) in the main chain, and includes a component containing a hydroxyl group in the side chain, and co-expressed by the following general formula containing no fluorine (2) A polymer;
An antireflection film comprising a low refractive index layer formed by curing a coating solution composition containing a fluorine-containing copolymer.
General formula (1):

In General Formula (1), R ¹¹ and R ¹² represent a hydrogen atom, an alkyl group, or an aryl group. p represents an integer of 10 to 500.
General formula (2):

In general formula (2), X represents a unit containing a polysiloxane structure represented by general formula (1). Y represents a polymerized unit based on an arbitrary vinyl monomer, and may be composed of a single component or a plurality of components. R ²¹ represents a hydrogen atom or a methyl group, and L ²¹ represents a single bond or a divalent linking group. x to z each represents a mole fraction (%) of each constituent component, and represents values satisfying 10 ≦ x <100, 0 ≦ y ≦ 50, 0 <z ≦ 50, and 0 <y + z ≦ 90. The antireflection film according to claim 1, wherein the fluorine-containing copolymer is represented by the following general formula (3).
General formula (3):

In the general formula (3), ^{Rf 11} represents a perfluoroalkyl group having 1 to 5 carbon atoms, ^{Rf 12} represents a fluorine-containing alkyl group having a straight-chain, branched or alicyclic structure having from 1 to 30 carbon atoms, an ether bond You may have. B represents a polymerized unit based on a hydroxyl group-containing monomer. A represents a polymerization unit based on an arbitrary vinyl monomer, and may be a single component or a plurality of components. a to d each represent a mole fraction (%) of each constituent component, and represent values satisfying 30 ≦ a + b ≦ 90, 5 ≦ a ≦ 90, 0 ≦ b ≦ 70, 0 ≦ c ≦ 50, and 10 ≦ d. . The antireflection film according to claim 1 or 2 , wherein the coating liquid composition forming the low refractive index layer further contains a crosslinking agent capable of reacting with a hydroxyl group. The antireflection film according to claim 3 , wherein the crosslinking agent is a compound in which two or more carbon atoms substituted with an alkoxy group are present adjacent to a nitrogen atom in one molecule.   The main chain contains a component having a polysiloxane structure represented by the following general formula (1) and a side chain containing a component having a hydroxyl group and does not contain fluorine. A polymer;
  Fluorine-containing copolymer
  The manufacturing method of the antireflection film which has the process of forming a low-refractive-index layer by hardening the coating liquid composition containing these.
  General formula (1):

  In general formula (1), R ¹¹ , R ¹² Represents a hydrogen atom, an alkyl group, or an aryl group. p represents an integer of 10 to 500.
  General formula (2):

  In general formula (2), X represents a unit containing a polysiloxane structure represented by general formula (1). Y represents a polymerized unit based on an arbitrary vinyl monomer, and may be composed of a single component or a plurality of components. R ²¹ Represents a hydrogen atom or a methyl group, L ²¹ Represents a single bond or a divalent linking group. x to z each represents a mole fraction (%) of each constituent component, and represents values satisfying 10 ≦ x <100, 0 ≦ y ≦ 50, 0 <z ≦ 50, and 0 <y + z ≦ 90. A polarizing plate antireflection film as described in any one of claims 1-4, characterized in that is used in one of two protective films of the polarizing film in the polarizing plate. An image display device, wherein the antireflection film according to any one of claims 1 to 4 or the polarizing plate according to claim 6 is used on an outermost surface of a display.

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