JP2013097163A - Composition for forming antistatic hard coat layer, optical film, method for manufacturing optical film, polarizing plate, and image display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a composition allowing formation of an antistatic hard coat layer that is excellent in the viewpoint of antistatic property, film hardness and brittleness and contributes to cost reduction by decreasing a use amount of an ionic conductive compound as an antistatic agent.SOLUTION: The composition for forming an antistatic hard coat layer comprises: (a) an ionic conductive compound; (b) a compound having three or more unsaturated double bonds and an isocyanuric ring or a phosphoric acid group in the molecule; (c) a compound having three or more unsaturated double bonds and a weight average molecular weight of 900 or less; (d) a photopolymerization initiator; and (e) a solvent.

Description

  The present invention relates to an antistatic hard coat layer forming composition, an optical film, a method for producing an optical film, a polarizing plate, and an image display device.

  In image display devices such as cathode ray tube display (CRT), plasma display (PDP), electroluminescence display (ELD), fluorescent display (VFD), field emission display (FED), and liquid crystal display (LCD), In order to prevent the visibility from being deteriorated due to scratches on the display surface or adhesion of dust or the like, it is preferable to provide an optical film that is transparent and has antistatic properties and hard coat properties.

  In order to obtain an optical film having antistatic properties and hard coat properties, an ion conductive compound such as a quaternary ammonium base-containing polymer as an antistatic agent and a polyfunctional monomer serving as a binder are provided on a transparent substrate. It is known that an antistatic hard coat layer is formed using a composition contained (for example, Patent Documents 1 to 3).

The antistatic hard coat layers obtained by conventional techniques such as Patent Documents 1 to 3 are excellent in terms of hardness because of using a polyfunctional monomer, but are inferior in terms of brittleness. If inferior in terms of brittleness, there are problems such as cracking of the film when the optical film is made into a roll form, poor handling at the time of polarizing plate processing, and a decrease in yield.
If the ion conductive compound and the polyfunctional monomer are poorly compatible, the ion conductive compound aggregates, and sufficient antistatic properties cannot be obtained unless a large amount of the ion conductive compound is added. However, since the use of a large amount of the ion conductive compound leads to an increase in cost, it is required to obtain sufficient antistatic properties with a small amount of the ion conductive compound.

JP 2009-86660 A Japanese Patent No. 4678451 JP 2006-188016 A

An object of the present invention is to provide an antistatic hard coat layer that is excellent in terms of antistatic properties, film hardness, and brittleness, and that can contribute to cost reduction by reducing the amount of an ion conductive compound that is an antistatic agent. Providing a composition capable of forming
Another object of the present invention is to provide an optical film having an antistatic hard coat layer excellent in terms of antistatic properties, film hardness and brittleness, a polarizing plate having the optical film, an image display device, and the optical film. It is to provide a manufacturing method.

  The present inventors diligently studied to solve the above problems and found that the above problems can be solved by the following means.

一般式（Ｉ）中、Ｒ_１は水素原子、アルキル基、ハロゲン原子又は−ＣＨ_２ＣＯＯ⁻Ｍ^＋を表す。Ｙは水素原子又は−ＣＯＯ⁻Ｍ^＋を表す。Ｍ^＋はプロトン又はカチオンを表す。Ｌは−ＣＯＮＨ−、−ＣＯＯ−、−ＣＯ−又は−Ｏ−を表す。Ｊはアルキレン基、アリーレン基、又はこれらを組み合わせてなる基を表す。Ｑは下記群Ａから選ばれる基を表す。

式中、Ｒ_２、Ｒ_２’及びＲ_２’’は、それぞれ独立に、アルキル基を表す。Ｊはアルキレン基、アリーレン基、又はこれらを組み合わせてなる基を表す。Ｘ⁻はアニオンを表す。ｐ及びｑは、それぞれ独立に、０又は１を表す。

一般式（ＩＩ）、（ＩＩＩ）中、Ｒ_３、Ｒ_４、Ｒ_５及びＲ_６は、それぞれ独立に、アルキル基を表し、Ｒ_３とＲ_４及びＲ_５とＲ_６はそれぞれ互いに結合して含窒素複素環を形成してもよい。
Ａ、Ｂ及びＤは、それぞれ独立に、アルキレン基、アリーレン基、アルケニレン基、アリーレンアルキレン基、−Ｒ_７ＣＯＲ_８−、−Ｒ_９ＣＯＯＲ_１０ＯＣＯＲ_１１−、−Ｒ_１２ＯＣＲ_１３ＣＯＯＲ_１４−、−Ｒ_１５−（ＯＲ_１６）_ｍ−、−Ｒ_１７ＣＯＮＨＲ_１８ＮＨＣＯＲ_１９−、−Ｒ_２０ＯＣＯＮＨＲ_２１ＮＨＣＯＲ_２２−又は―Ｒ_２３ＮＨＣＯＮＨＲ_２４ＮＨＣＯＮＨＲ_２５−を表す。Ｅは単結合、アルキレン基、アリーレン基、アルケニレン基、アリーレンアルキレン基、−Ｒ_７ＣＯＲ_８−、−Ｒ_９ＣＯＯＲ_１０ＯＣＯＲ_１１−、−Ｒ_１２ＯＣＲ_１３ＣＯＯＲ_１４−、−Ｒ_１５−（ＯＲ_１６）_ｍ−、−Ｒ_１７ＣＯＮＨＲ_１８ＮＨＣＯＲ_１９−、−Ｒ_２０ＯＣＯＮＨＲ_２１ＮＨＣＯＲ_２２−又は―Ｒ_２３ＮＨＣＯＮＨＲ_２４ＮＨＣＯＮＨＲ_２５−又は−ＮＨＣＯＲ_２６ＣＯＮＨ−を表す。Ｒ_７、Ｒ_８、Ｒ_９、Ｒ_１１、Ｒ_１２、Ｒ_１４、Ｒ_１５、Ｒ_１６、Ｒ_１７、Ｒ_１９、Ｒ_２０、Ｒ_２２、Ｒ_２３、Ｒ_２５及びＲ_２６はアルキレン基を表す。Ｒ_１０、Ｒ_１３、Ｒ_１８、Ｒ_２１及びＲ_２４は、それぞれ独立に、アルキレン基、アルケニレン基、アリーレン基、アリーレンアルキレン基及びアルキレンアリーレン基から選ばれる連結基を表す。ｍは１〜４の正の整数を表す。Ｘ^‐はアニオンを表す。
Ｚ_１、Ｚ_２は−Ｎ＝Ｃ−基とともに５員又は６員環を形成するのに必要な非金属原子群を表し、≡Ｎ^＋［Ｘ⁻］−なる４級塩の形でＥに連結してもよい。
ｎは５〜３００の整数を表す。
６．
透明基材上に、上記１〜５のいずれか１項に記載の帯電防止性ハードコート層形成用組成物から形成された帯電防止性ハードコート層を有する光学フィルム。
７．
前記透明基材がセルロースアシレートフィルムである上記６に記載の光学フィルム。
８．
偏光膜と該偏光膜の両面を保護する２枚の保護フィルムを有する偏光板であって、該保護フィルムの少なくとも一方が上記６又は７に記載の光学フィルムである偏光板。
９．
上記６若しくは７に記載の光学フィルム、又は上記８に記載の偏光板を有する画像表示装置。
１０．
セルロースアシレートフィルム基材上に、帯電防止性ハードコート層を有する光学フィルムの製造方法であって、該セルロースアシレートフィルム基材上に上記１〜５のいずれか１項に記載の帯電防止性ハードコート層形成用組成物を塗布、硬化して帯電防止性ハードコート層を形成する工程を有する光学フィルムの製造方法。 1.
An antistatic hard coat layer forming composition containing the following (a), (b), (c), (d), and (e).
(A) an ion conductive compound (b) a compound having three or more unsaturated double bonds and having an isocyanuric ring or a phosphate group in the molecule (c) having three or more unsaturated double bonds, And a compound having a weight average molecular weight of 900 or less (d) a photopolymerization initiator (e) a solvent;
2. The composition for forming an antistatic hard coat layer according to 1 above, wherein the ratio of the component (b) to the total solid content of the composition for forming an antistatic hard coat layer is 20 to 80% by mass.
3.
The antistatic hard coat according to 1 or 2 above, wherein the component (e) contains at least one selected from the group consisting of methyl ethyl ketone, methyl isobutyl ketone, methyl acetate, ethyl acetate, dimethyl carbonate, and diethyl carbonate. Layer forming composition.
4).
4. The antistatic hard coat layer forming composition according to any one of 1 to 3, wherein the component (a) is a quaternary ammonium base-containing polymer.
5.
5. The antistatic hardware according to any one of 1 to 4, wherein the component (a) is a polymer having at least one unit of structural units represented by the following general formulas (I) to (III): A composition for forming a coat layer.

In the general formula (I), _{R 1} represents a hydrogen atom, an alkyl group, a halogen atom or _-CH 2 ^COO - represents an ^{M +.} Y represents a hydrogen atom or -COO ^- M ⁺ . M ⁺ represents a proton or a cation. L represents -CONH-, -COO-, -CO- or -O-. J represents an alkylene group, an arylene group, or a group formed by combining these. Q represents a group selected from the following group A.

In the formula, R ₂ , R ₂ ′ and R ₂ ″ each independently represents an alkyl group. J represents an alkylene group, an arylene group, or a group formed by combining these. X ⁻ represents an anion. p and q each independently represents 0 or 1.

In the general formulas (II) and (III), R ₃ , R ₄ , R ₅ and R ₆ each independently represent an alkyl group, and R ₃ and R ₄ and R ₅ and R ₆ are bonded to each other. A nitrogen-containing heterocycle may be formed.
A, B and D are each independently an alkylene group, an arylene group, an alkenylene group, an arylenealkylene _{group, -R 7 COR 8 -, -} R 9 COOR 10 OCOR 11 -, - R 12 OCR 13 COOR 14 -, - _{R 15 - (oR 16) m} -, - R 17 CONHR 18 NHCOR 19 -, - R 20 OCONHR 21 NHCOR 22 - or _-R 23 NHCONHR ₂₄ NHCONHR ₂₅ - represents a. E represents a single bond, an alkylene group, an arylene group, an alkenylene group, an arylene alkylene group, —R ₇ COR ₈ —, —R ₉ COOR ₁₀ OCOR ₁₁ —, —R ₁₂ OCR ₁₃ COOR ₁₄ —, —R ₁₅ — (OR _{16 ) m -, - R 17 CONHR} 18 NHCOR 19 -, - R 20 OCONHR 21 NHCOR 22 - or _-R 23 NHCONHR ₂₄ NHCONHR ₂₅ - or an _-NHCOR 26 CONH-. R ₇ , R ₈ , R ₉ , R ₁₁ , R ₁₂ , R ₁₄ , R ₁₅ , R ₁₆ , R ₁₇ , R ₁₉ , R ₂₀ , R ₂₂ , R ₂₃ , R ₂₅ and R ₂₆ represent an alkylene group. R ₁₀ , R ₁₃ , R ₁₈ , R ₂₁ and R ₂₄ each independently represent a linking group selected from an alkylene group, an alkenylene group, an arylene group, an arylene alkylene group and an alkylene arylene group. m represents a positive integer of 1 to 4. X ⁻ represents an anion.
Z ₁ and Z ₂ represent a group of nonmetallic atoms necessary to form a 5-membered or 6-membered ring together with —N═C— group, and are represented by E in the form of a quaternary salt of ≡N ⁺ [X ⁻ ] —. You may connect.
n represents an integer of 5 to 300.
6).
An optical film having an antistatic hard coat layer formed from the antistatic hard coat layer forming composition according to any one of 1 to 5 above on a transparent substrate.
7).
7. The optical film as described in 6 above, wherein the transparent substrate is a cellulose acylate film.
8).
8. A polarizing plate comprising a polarizing film and two protective films for protecting both surfaces of the polarizing film, wherein at least one of the protective films is the optical film described in 6 or 7 above.
9.
8. An image display device comprising the optical film described in 6 or 7 or the polarizing plate described in 8 above.
10.
It is a manufacturing method of the optical film which has an antistatic hard-coat layer on a cellulose acylate film base material, Comprising: Antistatic property of any one of said 1-5 on this cellulose acylate film base material The manufacturing method of the optical film which has the process of apply | coating and hardening | curing the composition for hard-coat layer formation, and forming an antistatic hard-coat layer.

According to the present invention, an antistatic hard coat layer that is excellent in terms of antistatic properties, film hardness, and brittleness, and that can contribute to cost reduction by reducing the amount of an ion conductive compound that is an antistatic agent. The composition which can form is provided.
Further, according to the present invention, an optical film having an antistatic hard coat layer excellent in antistatic properties, film hardness, and brittleness, a polarizing plate having the optical film, an image display device, and the optical film The manufacturing method of can be provided.

Hereinafter, although the form for implementing this invention is demonstrated in detail, this invention is not limited to these. In the present specification, when a numerical value represents a physical property value, a characteristic value, etc., the description “(numerical value 1) to (numerical value 2)” means “(numerical value 1) or more and (numerical value 2) or less”. . In the present specification, the description “(meth) acrylate” means “at least one of acrylate and methacrylate”. The same applies to “(meth) acrylic acid”, “(meth) acryloyl” and the like.
In the present invention, “a repeating unit corresponding to a monomer” and “a repeating unit derived from a monomer” mean that a component obtained after polymerization of the monomer becomes a repeating unit.

The antistatic hard coat layer forming composition of the present invention contains the following (a), (b), (c), (d), and (e).
(A) an ion conductive compound (b) a compound having three or more unsaturated double bonds and having an isocyanuric ring or a phosphate group in the molecule (c) having three or more unsaturated double bonds, And a compound having a weight average molecular weight of 900 or less (d) a photopolymerization initiator (e) a solvent

  Hereinafter, the composition for forming an antistatic hard coat layer in the present invention will be described.

[(A) component: ion conductive compound]
The composition for forming an antistatic hard coat layer in the present invention contains an ion conductive compound.
Examples of the (a) ion conductive compound used in the present invention include cationic, anionic and amphoteric ion conductive compounds.
Among these, cationic and nonionic compounds that can easily obtain the effects of the present invention are preferable, and a compound having a quaternary ammonium base (cationic compound) is particularly preferable from the viewpoint of high antistatic performance of the compound.

As the compound having a quaternary ammonium base, either a low molecular type or a high molecular type can be used, but a high molecular cationic antistatic agent is more preferable because there is no variation in antistatic properties due to bleedout or the like. Used.
As the cationic compound having a polymer type quaternary ammonium base, it can be appropriately selected from known compounds, but is preferably a quaternary ammonium base-containing polymer from the viewpoint of high ion conductivity. A polymer having at least one unit of structural units represented by the following general formulas (I) to (III) is preferable.

In the general formula (I), _{R 1} represents a hydrogen atom, an alkyl group, a halogen atom or _-CH 2 ^COO - represents an ^{M +.} Y represents a hydrogen atom or -COO ^- M ⁺ . M ⁺ represents a proton or a cation. L represents -CONH-, -COO-, -CO- or -O-. J represents an alkylene group, an arylene group, or a group formed by combining these. Q represents a group selected from the following group A.

In the formula, R ₂ , R ₂ ′ and R ₂ ″ each independently represents an alkyl group. J represents an alkylene group, an arylene group, or a group formed by combining these. X ⁻ represents an anion. p and q each independently represents 0 or 1.

In the general formulas (II) and (III), R ₃ , R ₄ , R ₅ and R ₆ each independently represent an alkyl group, and R ₃ and R ₄ and R ₅ and R ₆ are bonded to each other. A nitrogen-containing heterocycle may be formed.
A, B and D are each independently an alkylene group, an arylene group, an alkenylene group, an arylenealkylene _{group, -R 7 COR 8 -, -} R 9 COOR 10 OCOR 11 -, - R 12 OCR 13 COOR 14 -, - _{R 15 - (oR 16) m} -, - R 17 CONHR 18 NHCOR 19 -, - R 20 OCONHR 21 NHCOR 22 - or _-R 23 NHCONHR ₂₄ NHCONHR ₂₅ - represents a. E represents a single bond, an alkylene group, an arylene group, an alkenylene group, an arylene alkylene group, —R ₇ COR ₈ —, —R ₉ COOR ₁₀ OCOR ₁₁ —, —R ₁₂ OCR ₁₃ COOR ₁₄ —, —R ₁₅ — (OR _{16 ) m -, - R 17 CONHR} 18 NHCOR 19 -, - R 20 OCONHR 21 NHCOR 22 - or _-R 23 NHCONHR ₂₄ NHCONHR ₂₅ - or an _-NHCOR 26 CONH-. R ₇ , R ₈ , R ₉ , R ₁₁ , R ₁₂ , R ₁₄ , R ₁₅ , R ₁₆ , R ₁₇ , R ₁₉ , R ₂₀ , R ₂₂ , R ₂₃ , R ₂₅ and R ₂₆ represent an alkylene group. R ₁₀ , R ₁₃ , R ₁₈ , R ₂₁ and R ₂₄ each independently represent a linking group selected from an alkylene group, an alkenylene group, an arylene group, an arylene alkylene group and an alkylene arylene group. m represents a positive integer of 1 to 4. X ⁻ represents an anion.
Z _{1, Z 2} represents a nonmetallic atomic group necessary for forming a 5-membered or 6-membered ring together with -N = C-group, ≡N ⁺ [X ^{-] -} becomes 4 to E in the form of quaternary salt You may connect.
n represents an integer of 5 to 300.

The groups of general formulas (I) to (III) will be described.
Examples of the halogen atom include a chlorine atom and a bromine atom, and a chlorine atom is preferable.
The alkyl group is preferably a branched or straight chain alkyl group having 1 to 4 carbon atoms, and more preferably a methyl group, an ethyl group, or a propyl group.
The alkylene group is preferably an alkylene group having 1 to 12 carbon atoms, more preferably a methylene group, an ethylene group or a propylene group, and particularly preferably an ethylene group.
The arylene group is preferably an arylene group having 6 to 15 carbon atoms, more preferably phenylene, diphenylene, phenylmethylene group, phenyldimethylene group, or naphthylene group, and particularly preferably phenylmethylene group. These groups have a substituent. It may be.
The alkenylene group is preferably an alkylene group having 2 to 10 carbon atoms, and the arylene alkylene group is preferably an arylene alkylene group having 6 to 12 carbon atoms, and these groups may have a substituent.
Examples of the substituent that may be substituted for each group include a methyl group, an ethyl group, and a propyl group.

In general formula (I), R ₁ is preferably a hydrogen atom.
Y is preferably a hydrogen atom.
J is preferably a phenylmethylene group.
Q is preferably the following general formula (VI) selected from group A, and R ₂ , R ₂ ′ and R ₂ ″ are each a methyl group.
X ⁻ includes a halogen ion, a sulfonate anion, a carboxylate anion and the like, preferably a halogen ion, and more preferably a chlorine ion.
p and q are preferably 0 or 1, more preferably p = 0 and q = 1.

In general formulas (II) and (III), R ₃ , R ₄ , R ₅ and R ₆ are preferably a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms, more preferably a methyl group or an ethyl group. A methyl group is particularly preferred.
A, B and D are preferably each independently a substituted or unsubstituted alkylene group having 2 to 10 carbon atoms, an arylene group, an alkenylene group or an arylene alkylene group, preferably a phenyldimethylene group.
X ⁻ includes a halogen ion, a sulfonate anion, a carboxylate anion and the like, preferably a halogen ion, and more preferably a chlorine ion.
E is preferably E represents a single bond, an alkylene group, an arylene group, an alkenylene group, or an arylene alkylene group.
Examples of the 5-membered or 6-membered ring formed by Z ₁ and Z ₂ together with the —N═C— group include a diazoniabicyclooctane ring.

  Specific examples of the compound having units having structures represented by the general formulas (I) to (III) are shown below, but the present invention is not limited thereto. Of the subscripts (m, x, y, z, r and actual numerical values) in the following specific examples, m represents the number of repeating units of each unit, and x, y, z, r represents the number of each unit. Represents the molar ratio.

  (A) As the ion conductive compound, a compound having a polymerizable group in the molecule is preferable because it can improve the scratch resistance (film strength) of the antistatic hard coat layer.

  (A) As an ion conductive compound, a commercial item can also be used, for example, a product name "light ester DQ-100" (manufactured by Kyoeisha Chemical Co., Ltd.), a product name "Rioduras LAS-1211" (Toyo Ink Manufacturing ( Product name "purple UV-AS-102" (manufactured by Nippon Synthetic Chemicals Co., Ltd.), "NK oligo U-601, 201" (manufactured by Shin-Nakamura Chemical Co., Ltd.), and the like.

  The quaternary ammonium base-containing polymer suitably used as the ion conductive compound of the present invention is a polymer other than the structural units (ionic structural units) represented by the general formulas (I) to (III). May have units. By having polymerized units other than ionic structural units in the ion conductive compound, the solubility in a solvent and the compatibility with a compound having an unsaturated double bond and a photopolymerization initiator are increased when preparing a composition. be able to.

  The following compounds are mentioned as an example of the monomer which can be used as superposition | polymerization units other than an ionic structural unit.

<Compound (a-2) having an alkylene oxide chain>
The compound (a-2) having an alkylene oxide chain is represented by the following general formula (2). For example, after ring-opening polymerization of ethylene oxide with an alkyl alcohol, transesterification with methyl (meth) acrylate, or (meta ) It can be obtained by reaction with acrylic acid chloride.
^{_{CH 2 = C (R 5)}} COO (AO) n R 6 (2)
(In the formula, R ⁵ represents H or CH ₃ , R ⁶ represents hydrogen or a hydrocarbon group having 1 to 22 carbon atoms, n represents an integer of 2 to 200, and A represents an alkylene group having 2 to 4 carbon atoms. )

In the general formula (2), the alkylene oxide group (AO) is an alkylene oxide group having 2 to 4 carbon atoms, and examples thereof include an ethylene oxide group, a propylene oxide group, and a butylene oxide group. Moreover, the alkylene oxide group from which carbon number differs may exist in the same monomer.
The number (n) of alkylene oxide groups is an integer of 2 to 200, preferably an integer of 10 to 100. It is preferable for it to be 2 to 200 since sufficient compatibility with a compound having an unsaturated double bond, which will be described later, is obtained.
R ⁶ is hydrogen or a hydrocarbon group having 1 to 22 carbon atoms. A carbon number of 23 or more is not practical because the raw material is expensive.
As the hydrocarbon group having 1 to 22 carbon atoms, a substituted or unsubstituted group can be selected, an unsubstituted group is preferable, and an unsubstituted alkyl group is preferable. As the unsubstituted alkyl group, any having or not having a branch can be used. Two or more of these may be used in combination.

  Specific examples of the compound (a-2) having an alkylene oxide chain include, for example, polyethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, polybutylene glycol mono (meth) acrylate, poly (ethylene glycol- Propylene glycol) mono (meth) acrylate, poly (ethylene glycol-tetramethylene glycol) mono (meth) acrylate, poly (propylene glycol-tetramethylene glycol) mono (meth) acrylate, polyethylene glycol mono (meth) acrylate monomethyl ether, polyethylene Glycol mono (meth) acrylate monobutyl ether, polyethylene glycol mono (meth) acrylate monooctyl ether, polyethylene glycol Cole mono (meth) acrylate monobenzyl ether, polyethylene glycol mono (meth) acrylate monophenyl ether, polyethylene glycol mono (meth) acrylate monodecyl ether, polyethylene glycol mono (meth) acrylate monododecyl ether, polyethylene glycol mono (meth) acrylate Monotetradecyl ether, polyethylene glycol mono (meth) acrylate monohexadecyl ether, polyethylene glycol mono (meth) acrylate monooctadecyl ether poly (ethylene glycol-propylene glycol) mono (meth) acrylate octyl ether, poly (ethylene glycol-propylene glycol) ) Mono (meth) acrylate octadecyl ether, poly (ethylene) Glycol - propylene glycol) mono (meth) acrylate nonylphenyl ether.

<Compound (a-3) copolymerizable with (a-2)>
Furthermore, you may radically copolymerize the compound (a-3) copolymerizable with the said (a-2) as needed.
The compound (a-3) copolymerizable with (a-2) is not particularly limited as long as it is a compound having one ethylenically unsaturated group. For example, methyl (meth) acrylate, ethyl Alkyl (meth) acrylates such as (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, dodecyl (meth) acrylate, octadecyl (meth) acrylate; hydroxyethyl (meth) acrylate , Hydroxyalkyl (meth) acrylates such as hydroxypropyl (meth) acrylate and hydroxybutyl (meth) acrylate; benzyl (meth) acrylate, cyclohexyl (meth) acrylate, isobornyl (meth) acrylate, dicyclopentenyl (meth) Various types (meth) such as acrylate, dicyclopentenyloxyethyl (meth) acrylate, ethoxyethyl (meth) acrylate, ethyl carbitol (meth) acrylate, butoxyethyl (meth) acrylate, cyanoethyl (meth) acrylate, glycidyl (meth) acrylate, etc. ) Acrylate, styrene, methylstyrene and the like.

  In the composition for forming an antistatic hard coat layer, only one (a) ionic conductive compound may be used, or two or more may be used in combination.

  The content of the (a) ion conductive compound in the composition for forming an antistatic hard coat layer is an amount sufficient to impart antistatic properties and is difficult to reduce film hardness, from the viewpoint of cost reduction. The antistatic hard coat layer forming composition is preferably 0.1% by mass to 10% by mass, more preferably 0.1% by mass to 5% by mass, and more preferably 0.1% by mass to 0.1% by mass based on the total solid content in the composition. 1% by mass is more preferable.

[Component (b): a compound having three or more unsaturated double bonds and having an isocyanuric ring or a phosphate group in the molecule]
The composition for forming an antistatic hard coat layer in the present invention contains (b) a compound having three or more unsaturated double bonds and having an isocyanuric ring or a phosphate group in the molecule. Since the component (b) has three or more unsaturated double bonds, the film hardness can be improved by curing. Furthermore, since the component (b) has an isocyanuric ring or a phosphate group, it can cause a weaker interaction than a covalent bond generated by polymerization of an unsaturated double bond, and it does not have many isocyanuric rings or phosphate groups. It is considered that the brittleness can be improved while maintaining the film hardness as compared with the case of using a functional monomer. In addition, the presence of a polar group such as an isocyanuric ring or a phosphate group increases the mobility of the counter anion, so that it is considered that sufficient antistatic properties can be exhibited even with a small amount of the ion conductive compound.

The component (b) has 3 or more unsaturated double bonds, but preferably has 3 or more and 6 or less unsaturated double bonds, preferably 3 or more and 4 or less, for the purpose of improving film hardness. Is more preferable.
Here, the unsaturated double bond that the component (b) has three or more is preferably an unsaturated double bond contained in the photopolymerizable group. Examples of the photopolymerizable group include (meth) From the viewpoint of good reactivity with other unsaturated double bond compounds such as acryloyl group, (meth) acryloyloxy group, vinyl group, allyl group, etc., (meth) acryloyloxy group is preferred, An acryloyloxy group is preferred.

  The component (b) has an isocyanuric ring or a phosphate group in the molecule. That is, the component (b) has a structure of the following formula (b-1) or (b-2) in the molecule.

  (B) A commercial item can also be used as a component. For example, NK ester A-9300 (ethoxylated isocyanuric acid triacrylate) manufactured by Shin-Nakamura Chemical Co., Ltd., Funkrill FA-731A (Tris (2-acryloyloxyethyl) isocyanurate) manufactured by Hitachi Chemical Co., Ltd., Toa Examples include Aronix M-315 (Isocyanuric acid EO-modified triacrylate) manufactured by Synthesizer Co., Ltd., Biscoat V # 3PA (Trisacryloyloxyethyl phosphate) manufactured by Osaka Organic Chemical Industry Co., Ltd., and the like.

  In the composition for forming an antistatic hard coat layer, only one type of component (b) may be used, or two or more types may be used in combination.

  In view of the fact that the content of the component (b) in the composition for forming an antistatic hard coat layer of the present invention is an amount sufficient to impart antistatic properties and the film hardness and brittleness are not easily impaired. 20 mass% or more and 80 mass% or less are preferable with respect to the total solid in the composition for prevention hard coat layer formation, 25 mass% or more and 75 mass% or less are more preferable, and 35 mass% or more and 60 mass% or less are further. preferable.

[Component (c): Compound having three or more unsaturated double bonds and a weight average molecular weight of 900 or less]
The composition for forming an antistatic hard coat layer in the present invention contains (c) a compound having three or more unsaturated double bonds and a weight average molecular weight of 900 or less. Since the component (c) has three or more unsaturated double bonds, the film hardness can be improved by curing. Furthermore, since the component (c) has a weight average molecular weight of 900 or less, it is considered that the component (c) easily penetrates into the base material when applied to the base material and can improve the brittleness of the film. In addition, since the component (c) is unevenly distributed on the substrate side, the (a) ion conductive compound is likely to be unevenly distributed on the air interface side (the side opposite to the substrate), so that a small amount of (a) ion conductivity is obtained. Even with a compound, sufficient antistatic properties can be obtained, which can contribute to the cost reduction of the antistatic hard coat layer.
The component (c) is a component different from the component (b).

The component (c) has 3 or more unsaturated double bonds, but preferably has 3 or more and 6 or less unsaturated double bonds, preferably 3 or more and 4 or less, for the purpose of improving the film hardness. Is more preferable.
Here, the unsaturated double bond that the component (c) has three or more is preferably an unsaturated double bond contained in a photopolymerizable group, and the photopolymerizable group includes (meth) Examples include compounds having a polymerizable functional group such as acryloyl group, vinyl group, styryl group, and allyl group. Among them, (meth) acryloyl group and —C (O) OCH═CH ₂ are preferable, and (meth) is more preferable. An acryloyl group.

  The weight average molecular weight of component (c) is preferably 200 or more and 900 or less, more preferably 250 or more and 600 or less, and still more preferably 300 or more and 600 or less, for the reason that film hardness and antistatic properties are compatible.

  Component (c) includes alkylene glycol (meth) acrylic acid diesters, polyoxyalkylene glycol (meth) acrylic acid diesters, polyhydric alcohol (meth) acrylic acid diesters, ethylene oxide or propylene oxide adducts. Examples include (meth) acrylic acid diesters, epoxy (meth) acrylates, urethane (meth) acrylates, and polyester (meth) acrylates.

  Among these, esters of polyhydric alcohol and (meth) acrylic acid are preferable. For example, pentaerythritol tetra (meth) acrylate, pentaerythritol tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, EO modified trimethylolpropane tri (meth) acrylate, PO modified trimethylolpropane tri (meth) acrylate, EO Modified tri (meth) acrylate phosphate, trimethylolethane tri (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa ( (Meth) acrylate, pentaerythritol hexa (meth) acrylate, 1,2,3-chlorohexane tetramethacrylate, polyurethane polyacrylate Over DOO, polyester polyacrylate and caprolactone-modified tris (acryloyloxyethyl) isocyanurate.

  (C) A commercial item can also be used as a component. For example, KAYARAD DPHA manufactured by Nippon Kayaku Co., Ltd., Shin Nakamura Chemical Co., Ltd. NK Ester A-TMMT, Osaka Organic Chemical Co., Ltd. V # 295, Daicel UCB Co., Ltd. EB5129, EB1290, etc. Can do.

  In the composition for forming an antistatic hard coat layer, only one type of component (c) may be used, or two or more types may be used in combination.

  The content of the component (c) in the composition for forming an antistatic hard coat layer gives a sufficient polymerization rate and imparts hardness and the like, so that the total solid content in the composition for forming an antistatic hard coat layer 20-80 mass% is preferable, 25-75 mass% is more preferable, and 40-65 mass% is still more preferable.

[(D) component: photopolymerization initiator]
The composition for forming an antistatic hard coat layer in the present invention contains (d) a photopolymerization initiator.
As photopolymerization initiators, acetophenones, benzoins, benzophenones, phosphine oxides, ketals, anthraquinones, thioxanthones, azo compounds, peroxides, 2,3-dialkyldione compounds, disulfide compounds, Examples include fluoroamine compounds, aromatic sulfoniums, lophine dimers, onium salts, borate salts, active esters, active halogens, inorganic complexes, and coumarins. Specific examples, preferred embodiments, commercially available products, and the like of the photopolymerization initiator are described in paragraphs [0133] to [0151] of JP-A-2009-098658, and can be suitably used in the present invention as well. it can.

  “Latest UV Curing Technology” {Technical Information Association, Inc.} (1991), p. 159, and “UV Curing System” written by Kiyomi Kato (published by General Technology Center in 1989), p. Various examples are also described in 65-148 and are useful in the present invention.

  In the composition for forming an antistatic hard coat layer, only one type of (d) photopolymerization initiator may be used, or two or more types may be used in combination.

  The content of the (d) photopolymerization initiator in the antistatic hard coat layer forming composition is sufficiently high to polymerize the polymerizable compound contained in the antistatic hard coat layer forming composition, and From the reason that it is set to a sufficiently small amount so that the starting point does not increase too much, it is preferably 0.5 to 8% by mass, preferably 1 to 5% by mass with respect to the total solid content in the composition for forming an antistatic hard coat layer. % Is more preferable.

[(E) component: solvent]
The composition for forming an antistatic hard coat layer in the present invention contains (e) a solvent.
The composition for forming an antistatic hard coat layer in the present invention preferably contains a hydrophilic solvent from the viewpoint of obtaining compatibility with (a) an ion conductive compound. Examples of the hydrophilic solvent include alcohol solvents, carbonate solvents, ester solvents and the like, for example, methanol, ethanol, isopropanol, n-butyl alcohol, cyclohexyl alcohol, 2-ethyl-1-hexanol, 2-methyl-1 Hexanol, 2-methoxyethanol, 2-propoxyethanol, 2-butoxyethanol, diacetone alcohol, dimethyl carbonate (dimethyl carbonate), diethyl carbonate (diethyl carbonate), diisopropyl carbonate, methyl ethyl carbonate, methyl n-propyl carbonate, Ethyl formate, propyl formate, pentyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, ethyl 2-ethoxypropionate, methyl acetoacetate , Ethyl acetoacetate, methyl 2-methoxyacetate, methyl 2-ethoxyacetate, ethyl 2-ethoxyacetate, acetone, 1,2-diacetoxyacetone, acetylacetone, etc., are used alone or in combination of two or more. Can be used.

  Further, a solvent other than the above may be used. For example, ether solvents, ketone solvents, aliphatic hydrocarbon solvents, aromatic hydrocarbon solvents and the like can be mentioned. For example, dibutyl ether, dimethoxyethane, diethoxyethane, propylene oxide, 1,4-dioxane, 1,3-dioxolane, 1,3,5-trioxane, tetrahydrofuran, anisole, phenetole, methyl ethyl ketone (MEK), diethyl ketone, dipropyl Ketone, diisobutyl ketone, cyclopentanone, cyclohexanone, methylcyclohexanone, methyl isobutyl ketone (MIBK), 2-octanone, 2-pentanone, 2-hexanone, ethylene glycol ethyl ether, ethylene glycol isopropyl ether, ethylene glycol butyl ether, propylene glycol methyl Ether, ethyl carbitol, butyl carbitol, hexane, heptane, octane, cyclohexane, methylcyclohexane Sun, ethylcyclohexane, benzene, toluene, xylene and the like, may be used in combination of at least one kind alone or two kinds.

  (E) Solvents include methyl ethyl ketone, methyl isobutyl ketone, methyl acetate, ethyl acetate, dimethyl carbonate because of the improvement in antistatic properties, the improvement in adhesion between the substrate and the hard coat layer, and the prevention of interference fringes. And at least one selected from the group consisting of diethyl carbonate, and methyl ethyl ketone, methyl acetate, and dimethyl carbonate are more preferable.

  The solid content concentration in the composition for forming an antistatic hard coat layer is preferably 20 to 80% by mass, more preferably 30 to 75% by mass, because the film hardness and antistatic property are compatible. More preferably, it is 40-70 mass%. The content of the solvent (e) in the antistatic hard coat layer forming composition is preferably such that the solid content concentration in the antistatic hard coat layer forming composition falls within the above range. .

Other components other than those described above can also be added to the composition for forming an antistatic hard coat layer of the present invention.
Hereinafter, the other components will be described.

(Surfactant)
It is also preferable to use various surfactants in the composition for forming an antistatic hard coat layer of the present invention. In general, a surfactant may suppress unevenness in film thickness due to drying variation due to local distribution of drying air, and may improve surface unevenness of an antistatic layer and repelling of a coated material. Furthermore, by improving the dispersibility of the antistatic compound, there are cases where more stable and high conductivity can be expressed, which is preferable.

  Specifically, the surfactant is preferably a fluorine-based surfactant or a silicone-based surfactant. Further, the surfactant is preferably an oligomer or a polymer rather than a low molecular compound.

  When a surfactant is added, the surfactant quickly moves to the surface of the applied liquid film and becomes unevenly distributed, and the surfactant is unevenly distributed on the surface even after the film is dried. The surface energy of the antistatic layer is reduced by the surfactant. From the viewpoint of preventing non-uniformity in film thickness, repellency, and unevenness of the antistatic layer, the surface energy of the film is preferably low.

  Preferred embodiments and specific examples of the fluorosurfactant are described in paragraph numbers [0023] to [0080] of JP-A-2007-102206, and the same applies to the present invention.

  Preferable examples of the silicone surfactant include those having a substituent at the end of the compound chain and / or the side chain, containing a plurality of dimethylsilyloxy units as repeating units. The compound chain containing dimethylsilyloxy as a repeating unit may contain a structural unit other than dimethylsilyloxy. The substituents may be the same or different, and a plurality of substituents are preferable. Examples of preferred substituents include groups containing a polyether group, an alkyl group, an aryl group, an aryloxy group, an aryl group, a cinnamoyl group, an oxetanyl group, a fluoroalkyl group, a polyoxyalkylene group, and the like.

  Although there is no restriction | limiting in particular in molecular weight, It is preferable that it is 100,000 or less, It is more preferable that it is 50,000 or less, It is especially preferable that it is 1000-30000, It is most preferable that it is 1000-20000.

Examples of preferable silicone compounds include “X-22-174DX”, “X-22-2426”, “X22-164C”, “X-22-176D” (trade names) manufactured by Shin-Etsu Chemical Co., Ltd. ); “FM-7725”, “FM-5521”, “FM-6621” (above product names) manufactured by Chisso Corporation; “DMS-U22”, “RMS-033” (above product names) manufactured by Gelest ); “SH200”, “DC11PA”, “ST80PA”, “L7604”, “FZ-2105”, “L-7604”, “Y-7006”, “SS-2801” manufactured by Toray Dow Corning Co., Ltd. (Product name); “TSF400” (product name); manufactured by Momentive Performance Materials Japan, but not limited thereto.
The surfactant is preferably contained in the total solid content of the coating composition for forming an antistatic hard coat layer in an amount of 0.01 to 0.5% by mass, more preferably 0.01 to 0.3% by mass. preferable.

(Translucent resin particles)
In the antistatic hard coat layer of the present invention, various translucent resin particles can be used in order to impart antiglare properties (surface scattering properties) and internal scattering properties.

As the translucent resin particles have no variation in particle size, the scattering characteristics are less varied and the design of the haze value becomes easier. As the translucent particles, plastic beads are preferable, and those having particularly high transparency and a difference in refractive index with the binder are preferable.
As organic particles, polymethyl methacrylate particles (refractive index 1.49), crosslinked poly (acryl-styrene) copolymer particles (refractive index 1.54), melamine resin particles (refractive index 1.57), polycarbonate particles ( Refractive index 1.57), polystyrene particles (refractive index 1.60), crosslinked polystyrene particles (refractive index 1.61), polyvinyl chloride particles (refractive index 1.60), benzoguanamine-melamine formaldehyde particles (refractive index 1. 68) etc. are used.

  Of these, cross-linked polystyrene particles, cross-linked poly ((meth) acrylate) particles, and cross-linked poly (acryl-styrene) particles are preferably used, and a binder is selected according to the refractive index of each light-transmitting particle selected from these particles. By adjusting the refractive index, the internal haze, surface haze, and centerline average roughness of the present invention can be achieved.

  The difference in refractive index between the binder and the translucent resin particles that can be used in the present invention (the refractive index of the translucent particles−the refractive index of the binder) is preferably 0.001 to 0.030 as an absolute value. . When the difference in refractive index is within this range, problems such as film character blurring, dark room contrast reduction, and surface turbidity do not occur.

  The average particle diameter (volume basis) of the translucent resin particles is preferably 0.5 to 20 μm. When the average particle diameter is within this range, the light scattering angle distribution does not become too wide, and there is no character blur on the display.

  Moreover, you may use together and use 2 or more types of translucent resin particles from which a particle diameter differs. It is possible to impart an antiglare property with a light-transmitting resin particle having a larger particle diameter, and to reduce surface roughness with a light-transmitting particle having a smaller particle diameter.

  When blending the translucent particles, it is preferably blended so as to be contained in an amount of 3 to 30% by mass in the total solid content of the antistatic hard coat layer. When the content is within this range, problems such as image blur, surface turbidity and glare can be prevented, and antistatic properties are not impaired.

[Optical film]
Hereinafter, the optical film of the present invention will be described.
The optical film of the present invention has an antistatic hard coat layer formed on the transparent substrate using the antistatic hard coat layer forming composition.
The optical film of the present invention has an antistatic hard coat layer on a transparent substrate, and may further include a single or a plurality of necessary functional layers depending on the purpose. For example, an antireflection layer (a layer having a refractive index adjusted, such as a low refractive index layer, a medium refractive index layer, or a high refractive index layer) can be provided.

The example of the more concrete layer structure of the optical film of this invention is shown below.
Transparent support / Antistatic hard coat layer Transparent support / Antistatic hard coat layer / Low refractive index layer Transparent support / Antistatic hard coat layer / High refractive index layer / Low refractive index layer Transparent support / Charge Preventive hard coat layer / medium refractive index layer / high refractive index layer / low refractive index layer

[Transparent substrate]
In the optical film of the present invention, various materials can be used as the transparent substrate (support), but a substrate containing a cellulose-based polymer is preferable, and a cellulose acylate film is more preferable.
Although it does not specifically limit as a cellulose acylate film, When installing in a display, since a cellulose triacetate film can be used as it is as a protective film which protects the polarizing layer of a polarizing plate, it is cellulose triacetate in terms of productivity and cost. A film is particularly preferred.
The thickness of the cellulose acylate film is usually about 25 μm to 1000 μm, but 40 μm to 200 μm is preferable because the handleability is good and the necessary substrate strength is obtained.

  In the present invention, it is preferable to use cellulose acetate having an acetylation degree of 59.0 to 61.5% for the cellulose acylate film. The degree of acetylation means the amount of bound acetic acid per unit mass of cellulose. The degree of acetylation follows the measurement and calculation of the degree of acetylation in ASTM: D-817-91 (test method for cellulose acetate and the like). The viscosity average degree of polymerization (DP) of cellulose acylate is preferably 250 or more, and more preferably 290 or more.

  The cellulose acylate used in the present invention has a Mw / Mn (Mw is a mass average molecular weight, Mn is a number average molecular weight) value by gel permeation chromatography close to 1.0, in other words, a molecular weight distribution. Narrow is preferred. The specific value of Mw / Mn is preferably 1.0 to 1.7, more preferably 1.3 to 1.65, and most preferably 1.4 to 1.6. preferable.

In general, the hydroxyl groups at 2, 3, and 6 positions of cellulose acylate are not evenly distributed by 1/3 of the total substitution degree, and the substitution degree of the 6-position hydroxyl group tends to be small. In the present invention, it is preferable that the substitution degree of the 6-position hydroxyl group of cellulose acylate is larger than that of the 2- and 3-positions.
The hydroxyl group at the 6-position with respect to the total substitution degree is preferably substituted with 32% or more of an acyl group, more preferably 33% or more, and particularly preferably 34% or more. Furthermore, the substitution degree of the 6-position acyl group of cellulose acylate is preferably 0.88 or more. The 6-position hydroxyl group may be substituted with a propionyl group, butyroyl group, valeroyl group, benzoyl group, acryloyl group or the like, which is an acyl group having 3 or more carbon atoms, in addition to the acetyl group. The degree of substitution at each position can be determined by NMR.

  In the present invention, cellulose acylate is described in paragraph Nos. 0043 to 0044, Examples, Synthesis Example 1, Paragraph Nos. 0048 to 0049, Synthesis Examples 2, Paragraph Nos. 0051 to 0052, and Synthesis Example 3 of JP-A No. 11-5851. The cellulose acetate obtained by the method can be used.

[Physical properties of antistatic hard coat layer]
The antistatic hard coat layer in the present invention preferably has a refractive index of 1.48 to 1.65. It is more desirably 1.48 to 1.60, and most preferably 1.48 to 1.55. Within the above range, interference unevenness with the substrate is suppressed, and when a low refractive index layer is further laminated, the reflection color can be neutralized, which is preferable.

The film thickness of the antistatic hard coat layer is preferably 1 μm or more, more preferably 3 μm to 20 μm, still more preferably 5 μm to 15 μm, and most preferably 6 μm to 15 μm. By setting it as the said range, physical strength and antistatic property can be made compatible.
Further, the strength of the antistatic hard coat layer is preferably 2H or more, more preferably 3H or more, in a pencil hardness test. Furthermore, in the Taber test according to JIS K5400, the smaller the wear amount of the test piece before and after the test, the better.

  The transmittance of the antistatic hard coat layer is preferably 80% or more, more preferably 85% or more, and most preferably 90% or more.

[Physical properties of optical film]
The surface resistivity of the optical film of the present invention is preferably as low as possible from the viewpoint of antistatic properties, and is 10 ¹⁰ Ω / sq. (Ω / □) or less is preferable, and 5 × 10 ⁹ Ω / sq. Or less, more preferably 10 ⁹ Ω / sq. It is as follows. By setting the surface resistivity within the above range, excellent dust resistance can be imparted.

(Optical film manufacturing method)
The optical film of the present invention can be formed by the following method, but is not limited to this method.
First, an antistatic hard coat layer forming composition is prepared. Next, the composition is applied onto a transparent support by dip coating, air knife coating, curtain coating, roller coating, wire bar coating, gravure coating, die coating, or the like, and heated and dried. A micro gravure coating method, a wire bar coating method, and a die coating method (see US Pat. No. 2,681,294 and JP-A-2006-122889) are more preferable, and a die coating method is particularly preferable.

After the coating, the layer formed from the composition for forming an antistatic hard coat layer is cured by drying and light irradiation, whereby an antistatic hard coat layer is formed. If necessary, other layers (layers constituting the film described below, for example, a hard coat layer, an antiglare layer, etc.) are coated on the transparent support in advance, and an antistatic hard coat is formed thereon. It is also possible to form layers. In this way, the optical film of the present invention is obtained.
The method for producing an optical film of the present invention includes a step of forming an antistatic hard coat layer by applying and curing the antistatic hard coat layer forming composition on a cellulose acylate film substrate. Is preferred.

(High refractive index layer and medium refractive index layer)
The optical film of the present invention may further have a high refractive index layer or a medium refractive index layer.
The refractive index of the high refractive index layer is preferably 1.65 to 2.20, and more preferably 1.70 to 1.80. The refractive index of the middle refractive index layer is adjusted to be a value between the refractive index of the low refractive index layer and the refractive index of the high refractive index layer. The refractive index of the medium refractive index layer is preferably 1.55 to 1.65, and more preferably 1.58 to 1.63.
The high refractive index layer and the medium refractive index layer are formed by chemical vapor deposition (CVD) or physical vapor deposition (PVD), particularly by vacuum vapor deposition or sputtering, which is a kind of physical vapor deposition, to form an inorganic oxide transparent thin film. Although it can be used, an all wet coating method is preferred.

  The medium refractive index layer and the high refractive index layer are not particularly limited as long as they are in the above refractive index range, but known components can be used as the constituent components. Specifically, paragraph number [0074] of JP-A-2008-262187 can be used. ] To [0094].

(Low refractive index layer)
The optical film of the present invention preferably has a low refractive index layer on the antistatic hard coat layer directly or via another layer. In this case, the optical film of the present invention can function as an antireflection film.
In this case, the low refractive index layer preferably has a refractive index of 1.30 to 1.51. It is preferably 1.30 to 1.46, more preferably 1.32 to 1.38. Within the above range, the reflectance can be suppressed and the film strength can be maintained, which is preferable. The low refractive index layer can be formed by a chemical vapor deposition (CVD) method or a physical vapor deposition (PVD) method, particularly a vacuum vapor deposition method or a sputtering method, which is a kind of physical vapor deposition method. It is preferable to use an all wet coating method using the composition for a low refractive index layer.

  The low refractive index layer is not particularly limited as long as it is a layer having the above refractive index range, but a known component can be used as a constituent component. Specifically, the fluorine-containing curability described in JP-A-2007-298974 can be used. A composition containing a resin and inorganic fine particles and a hollow silica fine particle-containing low refractive index coating described in JP-A Nos. 2002-317152, 2003-202406, and 2003-292831 are preferably used. be able to.

[Protective film for polarizing plate]
When the optical film is used as a surface protective film for a polarizing film (protective film for polarizing plate), the surface of the transparent support opposite to the side having the thin film layer, that is, the surface to be bonded to the polarizing film is hydrophilized. By performing so-called saponification treatment, it is possible to improve adhesiveness with a polarizing film containing polyvinyl alcohol as a main component.
Of the two protective films of the polarizer, the film other than the optical film is preferably an optical compensation film having an optical compensation layer comprising an optical anisotropic layer. The optical compensation film (retardation film) can improve the viewing angle characteristics of the liquid crystal display screen.
A known film can be used as the optical compensation film, but the optical compensation film described in JP-A-2001-100042 is preferable in terms of widening the viewing angle.

The saponification process described above will be described. The saponification treatment is a treatment in which an optical film is immersed in a heated alkaline aqueous solution for a certain period of time and washed with water, followed by acid washing for neutralization. As long as the surface of the transparent support to be bonded to the polarizing film is submerged, any processing conditions can be used. The concentration of the processing agent, the temperature of the processing agent solution, and the processing time are appropriately determined. The processing conditions are determined so that processing can be performed within 3 minutes from the need to ensure the performance. As general conditions, the alkali concentration is 3% by mass to 25% by mass, the treatment temperature is 30 ° C. to 70 ° C., and the treatment time is 15 seconds to 5 minutes. Sodium hydroxide and potassium hydroxide are preferable as the alkali species used for the alkali treatment, sulfuric acid is preferable as the acid used for the acid cleaning, and ion-exchanged water or pure water is preferable as the water used for the water cleaning.
Even if the antistatic layer of the optical film of the present invention is exposed to an alkaline aqueous solution by such a saponification treatment, the antistatic performance is maintained well.

  When the optical film of the present invention is used as a surface protective film for a polarizing film (protective film for polarizing plate), the cellulose acylate film is preferably a cellulose triacetate film.

[Polarizer]
Next, the polarizing plate of the present invention will be described.
The polarizing plate of the present invention is a polarizing plate having a polarizing film and two protective films for protecting both surfaces of the polarizing film, and at least one of the protective films is the optical film or the antireflection film of the present invention.

  Examples of the polarizing film include an iodine polarizing film, a dye polarizing film using a dichroic dye, and a polyene polarizing film. The iodine-based polarizing film and the dye-based polarizing film can be generally produced using a polyvinyl alcohol film.

  A structure in which the cellulose acylate film of the optical film is adhered to the polarizing film through an adhesive layer made of polyvinyl alcohol, if necessary, and a protective film is also provided on the other side of the polarizing film. The surface of the other protective film opposite to the polarizing film may have an adhesive layer.

  By using the optical film of the present invention as a protective film for a polarizing plate, a polarizing plate excellent in physical strength, antistatic properties and durability can be produced.

  Moreover, the polarizing plate of the present invention can also have an optical compensation function. In that case, only one side of either the front surface or the back surface of the two surface protective films is formed using the optical film, and the side having the optical film of the polarizing plate is the surface protective film on the other surface side. Is preferably an optical compensation film.

  By producing a polarizing plate using the optical film of the present invention as one of the protective films for polarizing plates and the optical compensation film having optical anisotropy as the other protective film of the polarizing film, It can improve the contrast in the bright room and the viewing angle of up, down, left and right.

[Image display device]
The image display device of the present invention has the optical film or polarizing plate of the present invention on the outermost surface of the display.
The optical film and the polarizing plate of the present invention are preferably used for an image display device such as a liquid crystal display device (LCD), a plasma display panel (PDP), an electroluminescence display (ELD), or a cathode ray tube display device (CRT). it can.
In particular, it can be advantageously used in an image display device such as a liquid crystal display device, and in a transmissive / semi-transmissive liquid crystal display device, it is particularly preferably used as the outermost layer on the backlight side of a liquid crystal cell.
In general, a liquid crystal display device has a liquid crystal cell and two polarizing plates arranged on both sides thereof, and the liquid crystal cell carries a liquid crystal between two electrode substrates. Furthermore, one optically anisotropic layer may be disposed between the liquid crystal cell and one polarizing plate, or two optically anisotropic layers may be disposed between the liquid crystal cell and both polarizing plates.
The liquid crystal cell is preferably in TN mode, VA mode, OCB mode, IPS mode or ECB mode.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the scope of the present invention should not be construed as being limited thereto. Unless otherwise specified, “part” and “%” are based on mass.

[Production of optical film]
As shown below, a coating solution for forming an antistatic hard coat layer was prepared, and an antistatic hard coat layer was formed on a transparent substrate to prepare an optical film sample.

(Preparation of coating solution for antistatic hard coat layer)
(A) component, (b) component, (c) component, (d) component, and (e) component described in Table 1 below are added, and the resulting composition is put into a mixing tank and stirred. It filtered with the filter made from a polypropylene with the hole diameter of 0.4 micrometer, and was set as the antistatic hard-coat layer coating liquid of Examples 1-15 and Comparative Examples 1-4.
In Table 1, the content of the component (a), the component (b), the component (c), and the component (d) is expressed as a ratio (% by mass) to the total solid content of the coating solution for the antistatic hard coat layer. The content of the component (e) was expressed as a ratio (% by mass) to the total mass of the coating solution for an antistatic hard coat layer.

(Preparation of antistatic hard coat layer)
The antistatic hard coat layer coating solution was applied on a cellulose triacetate film (TDH60UF, manufactured by Fuji Film Co., Ltd., refractive index 1.48) as a transparent support having a layer thickness of 60 μm using a gravure coater. After drying at 60 ° C. for about 2 minutes, using a 160 W / cm air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) while purging with nitrogen so that the atmosphere has an oxygen concentration of 1.0% by volume or less, the illuminance The coating layer is cured by irradiating ultraviolet rays of 400 mW / cm ² and an irradiation amount of 150 mJ / cm ² to form an antistatic hard coat layer having a thickness of 10 μm. Examples 1 to 15 and Comparative Examples 1 to 4 A film sample was prepared.

(Evaluation of optical film)
Various characteristics of the optical film were evaluated by the following methods.

(1) Surface resistance An optical film sample was conditioned at a temperature of 25 ° C. and a relative humidity of 60% for 2 hours, then measured using a 4339B high resistance meter (manufactured by Agilent Technologies), and the surface resistance at an applied voltage of 100V. Values were evaluated according to the following criteria.
A: 1.0 × 10 ⁹ Ω / sq. Or less ○: 1.0 × 10 ⁹ Ω / sq. Larger, 5 × 10 ⁹ Ω / sq. Δ: 5 × 10 ⁹ Ω / sq. Larger, 1.0 × 10 ¹⁰ Ω / sq. X: 1.0 × 10 ¹⁰ Ω / sq. Greater than

(2) Pencil hardness After conditioning the optical film sample for 2 hours under the conditions of a temperature of 25 ° C. and a relative humidity of 60%, a test pencil (hardness H to 4H) specified by JIS-S-6006 is used. In accordance with the pencil hardness evaluation method specified by -5-4 (1999), the load was 4.9N. The pencil hardness is preferably 2H or higher, particularly preferably 3H or higher.

(3) Brittleness After the optical film sample was conditioned for 2 hours at a temperature of 25 ° C. and a relative humidity of 60%, the antistatic hard coat layer was wound around a roll having a different diameter with the antistatic hard coat layer outside. The presence or absence of cracks was determined, and the smallest diameter that did not crack was defined as the brittleness value, and evaluated according to the following criteria.
A: Less than 5 mm
○: 5 mm or more and less than 8 mm △: 8 mm or more and less than 10 mm ×: 10 mm or more

A-9300: Ethoxylated isocyanuric acid triacrylate (manufactured by Shin-Nakamura Chemical)
V # 3PA: Trisacryloyloxyethyl phosphate (Osaka Organic Chemical)
A-TMMT: Pentaerythritol tetraacrylate (manufactured by Shin-Nakamura Chemical)
V # 295: Trimethylolpropane triacrylate (Osaka Organic Chemical)
EB5129: Urethane acrylate (hexafunctional, manufactured by Daicel UCB)
DPHA: Dipentaerythritol pentaacrylate (Nippon Kayaku)
UV-1700B: urethane acrylate (10 functional, manufactured by Nippon Synthetic Chemical)
DPCA-60: DPHA caprolactone modified product (hexafunctional, Nippon Kayaku)
A-600: Polyethylene glycol diacrylate (bifunctional, manufactured by Shin-Nakamura Chemical)
EB1290: Urethane acrylate (hexafunctional, manufactured by Daicel UCB)
Irg. 184: Irgacure 184 (photopolymerization initiator, manufactured by Ciba Specialty Chemicals)
BLEMMER QA: N, N, N-trimethyl- (2-hydroxy-3-methacryloyloxypropyl) -ammonium chloride (manufactured by NOF Corporation)
DQ-100: dimethylaminoethyl methacrylate quaternized product (manufactured by Kyoeisha Chemical)

Claims (10)

An antistatic hard coat layer forming composition containing the following (a), (b), (c), (d), and (e).
(A) an ion conductive compound (b) a compound having three or more unsaturated double bonds and having an isocyanuric ring or a phosphate group in the molecule (c) having three or more unsaturated double bonds, And a compound having a weight average molecular weight of 900 or less (d) a photopolymerization initiator (e) a solvent   The composition for forming an antistatic hard coat layer according to claim 1, wherein the ratio of the component (b) to the total solid content of the composition for forming an antistatic hard coat layer is 20 to 80% by mass.   The antistatic hard according to claim 1 or 2, wherein the component (e) includes at least one selected from the group consisting of methyl ethyl ketone, methyl isobutyl ketone, methyl acetate, ethyl acetate, dimethyl carbonate, and diethyl carbonate. A composition for forming a coat layer.   The composition for forming an antistatic hard coat layer according to any one of claims 1 to 3, wherein the component (a) is a quaternary ammonium base-containing polymer. The antistatic property according to any one of claims 1 to 4, wherein the component (a) is a polymer having at least one unit of structural units represented by the following general formulas (I) to (III). A composition for forming a hard coat layer.

In the general formula (I), _{R 1} represents a hydrogen atom, an alkyl group, a halogen atom or _-CH 2 ^COO - represents an ^{M +.} Y represents a hydrogen atom or -COO ^- M ⁺ . M ⁺ represents a proton or a cation. L represents -CONH-, -COO-, -CO- or -O-. J represents an alkylene group, an arylene group, or a group formed by combining these. Q represents a group selected from the following group A.

In the formula, R ₂ , R ₂ ′ and R ₂ ″ each independently represents an alkyl group. J represents an alkylene group, an arylene group, or a group formed by combining these. X ⁻ represents an anion. p and q each independently represents 0 or 1.

In the general formulas (II) and (III), R ₃ , R ₄ , R ₅ and R ₆ each independently represent an alkyl group, and R ₃ and R ₄ and R ₅ and R ₆ are bonded to each other. A nitrogen-containing heterocycle may be formed.
A, B and D are each independently an alkylene group, an arylene group, an alkenylene group, an arylenealkylene _{group, -R 7 COR 8 -, -} R 9 COOR 10 OCOR 11 -, - R 12 OCR 13 COOR 14 -, - _{R 15 - (oR 16) m} -, - R 17 CONHR 18 NHCOR 19 -, - R 20 OCONHR 21 NHCOR 22 - or _-R 23 NHCONHR ₂₄ NHCONHR ₂₅ - represents a. E represents a single bond, an alkylene group, an arylene group, an alkenylene group, an arylene alkylene group, —R ₇ COR ₈ —, —R ₉ COOR ₁₀ OCOR ₁₁ —, —R ₁₂ OCR ₁₃ COOR ₁₄ —, —R ₁₅ — (OR _{16 ) m -, - R 17 CONHR} 18 NHCOR 19 -, - R 20 OCONHR 21 NHCOR 22 - or _-R 23 NHCONHR ₂₄ NHCONHR ₂₅ - or an _-NHCOR 26 CONH-. R ₇ , R ₈ , R ₉ , R ₁₁ , R ₁₂ , R ₁₄ , R ₁₅ , R ₁₆ , R ₁₇ , R ₁₉ , R ₂₀ , R ₂₂ , R ₂₃ , R ₂₅ and R ₂₆ represent an alkylene group. R ₁₀ , R ₁₃ , R ₁₈ , R ₂₁ and R ₂₄ each independently represent a linking group selected from an alkylene group, an alkenylene group, an arylene group, an arylene alkylene group and an alkylene arylene group. m represents a positive integer of 1 to 4. X ⁻ represents an anion.
Z ₁ and Z ₂ represent a group of nonmetallic atoms necessary to form a 5-membered or 6-membered ring together with —N═C— group, and are represented by E in the form of a quaternary salt of ≡N ⁺ [X ⁻ ] —. You may connect.
n represents an integer of 5 to 300.   The optical film which has the antistatic hard-coat layer formed from the composition for antistatic hard-coat layer formation of any one of Claims 1-5 on a transparent base material.   The optical film according to claim 6, wherein the transparent substrate is a cellulose acylate film.   A polarizing plate comprising a polarizing film and two protective films protecting both surfaces of the polarizing film, wherein at least one of the protective films is the optical film according to claim 6 or 7.   An image display device comprising the optical film according to claim 6 or 7, or the polarizing plate according to claim 8.   It is a manufacturing method of the optical film which has an antistatic hard-coat layer on a cellulose acylate film base material, Comprising: On this cellulose acylate film base material, antistatic of any one of Claims 1-5 A method for producing an optical film comprising a step of applying and curing a composition for forming a hard coat layer to form an antistatic hard coat layer.