JP5970508B2 - Optical film, polarizing plate, optical film manufacturing method, and image display device - Google Patents

Description

  The present invention relates to an optical film, a polarizing plate, a method for producing a polarizing plate, and an image display device.

  In recent years, liquid crystal display devices have been widely used for liquid crystal panels such as liquid crystal televisions, personal computers, mobile phones, and digital cameras. Usually, a liquid crystal display device has a liquid crystal panel member provided with polarizing plates on both sides of a liquid crystal cell, and display is performed by controlling light from the backlight member with the liquid crystal panel member. Here, the polarizing plate comprises a polarizer and at least one protective film (polarizing plate protective film), and a general polarizer is made of a stretched polyvinyl alcohol (PVA) film by iodine or a dichroic dye. Films using various thermoplastic resins are used as protective films. Moreover, it is common to laminate | stack a hard-coat layer further in order to provide hardness to the visual recognition side protective film of the polarizing plate arrange | positioned at the visual recognition side.

As the thermoplastic resin film used for the polarizing plate protective film, a cellulose acylate film is generally used. However, because cellulose acylate is highly hygroscopic, it expands and contracts due to the humidity of the environment in which it is used. Unevenness is likely to occur. Therefore, it has also been proposed to use a cyclic polyolefin resin film excellent in moisture resistance as a polarizing plate protective film.
Patent Document 1 describes a polarizing plate protective film in which a hard coat layer is laminated on a resin film made of a norbornene-based polymer.
Patent Document 2 describes a polarizing plate protective film having a norbornene-based resin film and a hard coat layer.

JP 2006-30870 A JP 2009-20485 A

In recent years, liquid crystal display devices, particularly liquid crystal display devices for small and medium-sized applications, have been rapidly thinned, and it is an urgent task to reduce the thickness of members (optical films, polarizing plate protective films, polarizing plates, etc.) used. .
On the other hand, when a polarizing plate having a thinned polarizing plate protective film is incorporated into a liquid crystal display device and used in accordance with the thinning of the polarizing plate protective film, the polarizing plate protective film is absorbed due to moisture absorption in a high temperature and high humidity environment. The influence of the stress generated due to expansion and contraction becomes larger than when the film is not thinned. Due to the influence of this stress, warp unevenness in which the liquid crystal panel including the polarizing plate warps and light leakage occurs at the corners becomes a problem. Since it is known that the polarizing plate protective film expands and contracts due to moisture absorption, it is considered that this problem can be improved by using a film having low moisture permeability as the polarizing plate protective film.
As a means for lowering the moisture permeability of the protective film, it is conceivable to use a cyclic olefin resin which is a material having a very low moisture permeability. However, when the cyclic olefin resin is used as a polarizing plate protective film on the viewing side of the viewing side polarizing plate of the liquid crystal display device by studying the present inventors, when the hard coat layer is laminated, the hard coat layer and the cyclic olefin resin film are It was found that the adhesion of the resin was low and the surface hardness was low.

  An object of the present invention is an optical film having high wet heat durability even in a thin film, excellent adhesion to a hard coat layer, and high surface hardness, a polarizing plate having the optical film and a polarizer, and the optical film or An object of the present invention is to provide an image display device having this polarizing plate.

一般式（Ｉ）中、Ｌ、及びＬ’は各々独立に二価以上の連結基を表す。ｎは１〜３の整数を表す。

一般式（ＩＩ）中、Ｌ、及びＬ’は各々独立に二価以上の連結基を表す。ｎは１〜２の整数を表す。

一般式（ＩＩＩ）中、Ｌ、及びＬ’は各々独立に二価以上の連結基を表す。ｎは１〜２の整数を表す。

一般式（ＩＶ）中、Ｌ、及びＬ’は各々独立に二価以上の連結基を表し、Ｌ’’は水素原子または二価以上の連結基を表す。

一般式（Ｖ）中、Ｌ、及びＬ’は各々独立に二価以上の連結基を表す。
＜４＞
上記環状ポリオレフィン系樹脂が下記一般式（Ａ−ＩＩ）又は（Ａ−ＩＩＩ）で表される環状オレフィンに由来する構造単位を有する重合体である＜１＞〜＜３＞のいずれかに記載の光学フィルム。

一般式（Ａ−ＩＩ）〜（Ａ−ＩＩＩ）中、ｍは０〜４の整数を表す。Ｒ ³ 〜Ｒ ⁶ は各々独立に水素原子又は炭素数１〜１０の炭化水素基を表し、Ｘ ² 〜Ｘ ³ 、Ｙ ² 〜Ｙ ³ は各々独立に水素原子、炭素数１〜１０の炭化水素基、ハロゲン原子、ハロゲン原子で置換された炭素数１〜１０の炭化水素基、置換基を有していても良いビニル基、（メタ）アクリロイル基、−(ＣＨ ₂ ) _n ＣＯＯＲ ¹¹ 、−(ＣＨ ₂ ) _n ＯＣＯＲ ¹² 、−(ＣＨ ₂ ) _n ＮＣＯ、−(ＣＨ ₂ ) _n ＮＯ ₂ 、−(ＣＨ ₂ ) _n ＣＮ、−(ＣＨ ₂ ) _n ＣＯＮＲ ¹³ Ｒ ¹⁴ 、−(ＣＨ ₂ ) _n ＮＲ ¹³ Ｒ ¹⁴ 、−(ＣＨ ₂ ) _n ＯＺ、−(ＣＨ ₂ ) _n Ｗ、又はＸ ² とＹ ² あるいはＸ ³ とＹ ³ から構成された(−ＣＯ) ₂ Ｏ、(−ＣＯ) ₂ ＮＲ ¹⁵ を示す。なお、Ｒ ¹¹ ，Ｒ ¹² ，Ｒ ¹³ ，Ｒ ¹⁴ ，Ｒ ¹⁵ は各々独立に水素原子、炭素数１〜２０の炭化水素基、Ｚは炭化水素基又はハロゲンで置換された炭化水素基、ＷはＳｉＲ ¹⁶ _p Ｄ _3-p （Ｒ ¹⁶ は炭素数１〜１０の炭化水素基、Ｄはハロゲン原子、−ＯＣＯＲ ¹⁶ 又は−ＯＲ ¹⁶ 、ｐは０〜３の整数を示す）、ｎは０〜１０の整数を示す。
＜５＞
偏光子と＜１＞〜＜４＞のいずれかに記載の光学フィルムとを有する偏光板であって、
偏光子、（Ａ）層、（Ｂ）層をこの順に有する偏光板。
＜６＞
上記偏光子の膜厚が１０μｍ以下であり、偏光板全体の厚さが４０μｍ以下である＜５＞に記載の偏光板。
＜７＞
下記（ａ）〜（ｆ）の工程を有する＜１＞〜＜４＞のいずれかに記載の光学フィルムの製造方法。
（ａ）支持体上に、環状ポリオレフィン系樹脂と第一の溶媒とを含む第一の溶液を塗布して第一塗布層を形成する工程
（ｂ）上記第一塗布層に含まれる第一の溶媒を乾燥させて（Ａ）層を得る工程
（ｃ）上記（Ａ）層上に、分子中に脂環構造を有する重合性化合物と第二の溶媒とを含む第二の溶液を塗布して第二塗布層を形成する工程
（ｄ）上記第二塗布層に含まれる第二の溶媒を乾燥させる工程
（ｅ）上記第二塗布層に含まれる分子中に脂環構造を有する重合性化合物を、光及び／又は熱により重合して分子中に脂環構造を有する樹脂を得て、（Ｂ）層を得る工程
（ｆ）上記（Ａ）層と（Ｂ）層を含む積層体を、上記支持体から剥離する工程
＜８＞
＜１＞〜＜４＞のいずれかに記載の光学フィルム、又は＜５＞若しくは＜６＞に記載の偏光板を含む画像表示装置。
本発明は上記＜１＞〜＜８＞に記載した事項に関するものであるが参考のためにその他の事項についても記載した。 As a result of intensive studies by the present inventors, it has been found that the above problems can be solved by the following means.
<1>
(A) a layer containing a cyclic polyolefin resin;
(B) a layer containing a resin polymerized by light and / or heat having an alicyclic structure in the molecule;
(C) a hard coat layer;
In this order, the film thickness of the (C) layer is 10 μm or less.
<2>
The optical film according to <1>, wherein the film thickness of the (A) layer is 20 μm or less and the film thickness of the (B) layer is 20 μm or less.
<3>
The resin having a alicyclic structure in the molecule and polymerized with light and / or heat is a polymerizable compound having a group represented by any one of the following general formulas (I) to (V): light and / or heat. <1> or <2> is an optical film as described in <1>.

In general formula (I), L and L ′ each independently represent a divalent or higher linking group. n represents an integer of 1 to 3.

In general formula (II), L and L ′ each independently represent a divalent or higher linking group. n represents an integer of 1 to 2.

In general formula (III), L and L ′ each independently represent a divalent or higher linking group. n represents an integer of 1 to 2.

In general formula (IV), L and L ′ each independently represent a divalent or higher valent linking group, and L ″ represents a hydrogen atom or a divalent or higher valent linking group.

In general formula (V), L and L ′ each independently represent a divalent or higher linking group.
<4>
<1> to <3>, wherein the cyclic polyolefin-based resin is a polymer having a structural unit derived from a cyclic olefin represented by the following general formula (A-II) or (A-III). Optical film.

In general formulas (A-II) to (A-III), m represents an integer of 0 to 4. R ³ to R ⁶ each independently represent a hydrogen atom or a hydrocarbon group having 1 to 10 carbon ^{atoms, X 2 ~X 3, Y 2} ~Y 3 each independently represent a hydrogen atom, a hydrocarbon having 1 to 10 carbon atoms group, a halogen atom, a hydrocarbon group having 1 to 10 carbon atoms substituted with a halogen atom, which may have a substituent vinyl group, (meth) acryloyl _{group, - (CH 2) n COOR} 11, - ( _{^{CH 2) n OCOR 12, -}} (CH 2) n NCO, - (CH 2) n NO 2, - (CH 2) n CN, - (CH 2) n CONR 13 R 14, - (CH 2) n NR ¹³ R ¹⁴ , — (CH ₂ ) _n OZ, — (CH ₂ ) _n W, or (—CO) ₂ O, ( —CO ) ₂ NR ¹⁵ composed of X ² and Y ² or X ³ and Y ³ Indicates. R ¹¹ , R ¹² , R ¹³ , R ¹⁴ and R ¹⁵ are each independently a hydrogen atom, a hydrocarbon group having 1 to 20 carbon atoms, Z is a hydrocarbon group or a hydrocarbon group substituted with halogen, and W is SiR ¹⁶ _p D _3-p (R ¹⁶ is a hydrocarbon group having 1 to 10 carbon atoms, D is a halogen atom, —OCOR ¹⁶ or —OR ¹⁶ , p is an integer of 0 to 3), n is 0 to 10 Indicates an integer.
<5>
A polarizing plate having a polarizer and the optical film according to any one of <1> to <4>,
A polarizing plate having a polarizer, (A) layer, and (B) layer in this order.
<6>
The polarizing plate according to <5>, wherein the polarizer has a thickness of 10 μm or less and the entire polarizing plate has a thickness of 40 μm or less.
<7>
The manufacturing method of the optical film in any one of <1>-<4> which has the process of following (a)-(f).
(A) The process of apply | coating the 1st solution containing cyclic polyolefin resin and a 1st solvent on a support body, and forming a 1st application layer.
(B) A step of obtaining a layer (A) by drying the first solvent contained in the first coating layer.
(C) The process of apply | coating the 2nd solution containing the polymeric compound which has an alicyclic structure in a molecule | numerator, and a 2nd solvent on the said (A) layer, and forming a 2nd application layer.
(D) A step of drying the second solvent contained in the second coating layer.
(E) A polymerizable compound having an alicyclic structure in the molecule contained in the second coating layer is polymerized by light and / or heat to obtain a resin having an alicyclic structure in the molecule, and (B) layer The process of obtaining
(F) The process of peeling the laminated body containing the said (A) layer and (B) layer from the said support body.
<8>
<1>-<4> The image display apparatus containing the optical film as described in any one, or the polarizing plate as described in <5> or <6>.
The present invention relates to the items described in <1> to <8> above, but other items are also described for reference.

一般式（Ｉ）中、Ｌ、及びＬ’は各々独立に二価以上の連結基を表す。ｎは１〜３の整数を表す。

一般式（ＩＩ）中、Ｌ、及びＬ’は各々独立に二価以上の連結基を表す。ｎは１〜２の整数を表す。

一般式（ＩＩＩ）中、Ｌ、及びＬ’は各々独立に二価以上の連結基を表す。ｎは１〜２の整数を表す。

一般式（ＩＶ）中、Ｌ、及びＬ’は各々独立に二価以上の連結基を表し、Ｌ’’は水素原子または二価以上の連結基を表す。

一般式（Ｖ）中、Ｌ、及びＬ’は各々独立に二価以上の連結基を表す。
［６］
上記環状ポリオレフィン系樹脂が下記一般式（Ａ−ＩＩ）又は（Ａ−ＩＩＩ）で表される環状オレフィンに由来する構造単位を有する重合体である［１］〜［５］のいずれかに記載の光学フィルム。

一般式（Ａ−ＩＩ）〜（Ａ−ＩＩＩ）中、ｍは０〜４の整数を表す。Ｒ³〜Ｒ⁶は各々独立に水素原子又は炭素数１〜１０の炭化水素基を表し、Ｘ²〜Ｘ³、Ｙ²〜Ｙ³は各々独立に水素原子、炭素数１〜１０の炭化水素基、ハロゲン原子、ハロゲン原子で置換された炭素数１〜１０の炭化水素基、置換基を有していても良いビニル基、（メタ）アクリロイル基、−(ＣＨ₂)_nＣＯＯＲ¹¹、−(ＣＨ₂)_nＯＣＯＲ¹²、−(ＣＨ₂)_nＮＣＯ、−(ＣＨ₂)_nＮＯ₂、−(ＣＨ₂)_nＣＮ、−(ＣＨ₂)_nＣＯＮＲ¹³Ｒ¹⁴、−(ＣＨ₂)_nＮＲ¹³Ｒ¹⁴、−(ＣＨ₂)_nＯＺ、−(ＣＨ₂)_nＷ、又はＸ²とＹ²あるいはＸ³とＹ³から構成された(−ＣＯ)₂Ｏ、(−ＣＯ)₂ＮＲ¹⁵を示す。なお、Ｒ¹¹，Ｒ¹²，Ｒ¹³，Ｒ¹⁴，Ｒ¹⁵は各々独立に水素原子、炭素数１〜２０の炭化水素基、Ｚは炭化水素基又はハロゲンで置換された炭化水素基、ＷはＳｉＲ¹⁶ _pＤ_3-p（Ｒ¹⁶は炭素数１〜１０の炭化水素基、Ｄはハロゲン原子、−ＯＣＯＲ¹⁶又は−ＯＲ¹⁶、ｐは０〜３の整数を示す）、ｎは０〜１０の整数を示す。
［７］
偏光子と［１］〜［６］のいずれかに記載の光学フィルムとを有する偏光板であって、
偏光子、（Ａ）層、（Ｂ）層をこの順に有する偏光板。
［８］
上記偏光子の膜厚が１０μｍ以下であり、偏光板全体の厚さが４０μｍ以下である［７］に記載の偏光板。
［９］
下記（ａ）〜（ｆ）の工程を有する［１］〜［６］のいずれかに記載の光学フィルムの製造方法。
（ａ）支持体上に、環状ポリオレフィン系樹脂と第一の溶媒とを含む第一の溶液を塗布して第一塗布層を形成する工程
（ｂ）上記第一塗布層に含まれる第一の溶媒を乾燥させて（Ａ）層を得る工程
（ｃ）上記（Ａ）層上に、分子中に脂環構造を有する重合性化合物と第二の溶媒とを含む第二の溶液を塗布して第二塗布層を形成する工程
（ｄ）上記第二塗布層に含まれる第二の溶媒を乾燥させる工程
（ｅ）上記第二塗布層に含まれる分子中に脂環構造を有する重合性化合物を、光及び／又は熱により重合して分子中に脂環構造を有する樹脂を得て、（Ｂ）層を得る工程
（ｆ）上記（Ａ）層と（Ｂ）層を含む積層体を、上記支持体から剥離する工程
［１０］
［１］〜［６］のいずれかに記載の光学フィルム、又は［７］若しくは［８］に記載の偏光板を含む画像表示装置。 [1]
(A) a layer containing a cyclic polyolefin resin;
(B) a layer containing a resin polymerized by light and / or heat having an alicyclic structure in the molecule;
An optical film having
[2]
The optical film as described in [1], wherein the film thickness of the (A) layer is 20 μm or less, and the film thickness of the (B) layer is 20 μm or less.
[3]
And (C) a hard coat layer,
The optical film as described in [1] or [2] which has a (A) layer, a (B) layer, and a (C) layer in this order.
[4]
The optical film as described in [3], wherein the film thickness of the (C) layer is 10 μm or less.
[5]
The resin having a alicyclic structure in the molecule and polymerized with light and / or heat is a polymerizable compound having a group represented by any one of the following general formulas (I) to (V): light and / or heat. The optical film according to any one of [1] to [4], which is a resin polymerized in step (1).

In general formula (I), L and L ′ each independently represent a divalent or higher linking group. n represents an integer of 1 to 3.

In general formula (II), L and L ′ each independently represent a divalent or higher linking group. n represents an integer of 1 to 2.

In general formula (III), L and L ′ each independently represent a divalent or higher linking group. n represents an integer of 1 to 2.

In general formula (IV), L and L ′ each independently represent a divalent or higher valent linking group, and L ″ represents a hydrogen atom or a divalent or higher valent linking group.

In general formula (V), L and L ′ each independently represent a divalent or higher linking group.
[6]
The cyclic polyolefin resin according to any one of [1] to [5], wherein the cyclic polyolefin resin is a polymer having a structural unit derived from a cyclic olefin represented by the following general formula (A-II) or (A-III). Optical film.

In general formulas (A-II) to (A-III), m represents an integer of 0 to 4. R ^{3 to} R ⁶ each independently represent a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, and X ^{2 to} X ³ and Y ^{2 to} Y ³ each independently represent a hydrogen atom or a hydrocarbon having 1 to 10 carbon atoms. group, a halogen atom, a hydrocarbon group having 1 to 10 carbon atoms substituted with a halogen atom, which may have a substituent vinyl group, (meth) acryloyl _{group, - (CH 2) n COOR} 11, - ( ^{_{CH 2) n OCOR 12, -}} (CH 2) n NCO, - (CH 2) n NO 2, - (CH 2) n CN, - (CH 2) n CONR 13 R 14, - (CH 2) n NR ¹³ R ¹⁴ , — (CH ₂ ) _n OZ, — (CH ₂ ) _n W, or (—CO) ₂ O, (—CO) ₂ NR ¹⁵ composed of X ² and Y ² or X ³ and Y ³ Indicates. R ¹¹ , R ¹² , R ¹³ , R ¹⁴ and R ¹⁵ are each independently a hydrogen atom, a hydrocarbon group having 1 to 20 carbon atoms, Z is a hydrocarbon group or a hydrocarbon group substituted with halogen, and W is SiR ¹⁶ _p D _3-p (R ¹⁶ is a hydrocarbon group having 1 to 10 carbon atoms, D is a halogen atom, —OCOR ¹⁶ or —OR ¹⁶ , p is an integer of 0 to 3), n is 0 to 10 Indicates an integer.
[7]
A polarizing plate having a polarizer and the optical film according to any one of [1] to [6],
A polarizing plate having a polarizer, (A) layer, and (B) layer in this order.
[8]
The polarizing plate according to [7], wherein the polarizer has a thickness of 10 μm or less, and the entire polarizing plate has a thickness of 40 μm or less.
[9]
The manufacturing method of the optical film in any one of [1]-[6] which has the process of following (a)-(f).
(A) The process of apply | coating the 1st solution containing cyclic polyolefin-type resin and a 1st solvent on a support body, and forming a 1st application layer (b) The 1st contained in the said 1st application layer (C) A step of obtaining a layer by drying the solvent (c) A second solution containing a polymerizable compound having an alicyclic structure in the molecule and a second solvent is applied on the layer (A). Step of forming the second coating layer (d) Step of drying the second solvent contained in the second coating layer (e) A polymerizable compound having an alicyclic structure in the molecule contained in the second coating layer Step of obtaining a resin having an alicyclic structure in the molecule by polymerization with light and / or heat, and obtaining a layer (B) (f) A laminate comprising the layer (A) and the layer (B), Step of peeling from support [10]
An image display device comprising the optical film according to any one of [1] to [6] or the polarizing plate according to [7] or [8].

  According to the present invention, an optical film having high moisture resistance even in a thin film, excellent adhesion to a hard coat layer, and high surface hardness, a polarizing plate having the optical film and a polarizer, and the optical film or the optical film An image display device having a polarizing plate can be provided.

It is a cross-sectional schematic diagram of an example of the polarizing plate of this invention.

  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, or the like, the description “(numerical value 1) to (numerical value 2)” means “larger than (numerical value 1) and smaller than (numerical value 2)”. Represents. 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.

[Optical film]
The optical film of the present invention includes (A) a layer containing a cyclic polyolefin resin (also referred to as “(A) layer”), and (B) a resin polymerized by light and / or heat having an alicyclic structure in the molecule. Including a layer (also referred to as a “(B) layer”).

[(A) Layer containing cyclic polyolefin resin]
The optical film of the present invention has a layer ((A) layer) containing a cyclic polyolefin resin.

<(A) Cyclic polyolefin resin contained in layer>
The layer (A) contains a cyclic polyolefin resin. The cyclic polyolefin-based resin represents a polymer resin having a cyclic olefin structure.
Examples of the polymer resin having a cyclic olefin structure used in the present invention include (1) a norbornene polymer, (2) a monocyclic olefin polymer, (3) a cyclic conjugated diene polymer, (4) There are vinyl alicyclic hydrocarbon polymers and hydrides of (1) to (4).

As the cyclic polyolefin resin, a polymer having a structural unit derived from a cyclic olefin represented by the following general formula (A-II) or (A-III) is preferable.
The polymer having a structural unit represented by the following general formula (A-II) is a norbornene-based addition polymer, and the polymer having a structural unit represented by the following general formula (A-III) is a norbornene-based polymer. It is a ring-opening polymer.

In general formulas (A-II) to (A-III), m represents an integer of 0 to 4. R ^{3 to} R ⁶ each independently represent a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, and X ^{2 to} X ³ and Y ^{2 to} Y ³ each independently represent a hydrogen atom or a hydrocarbon having 1 to 10 carbon atoms. group, a halogen atom, a hydrocarbon group having 1 to 10 carbon atoms substituted with a halogen _{atom, - (CH 2) n COOR} 11, - (CH 2) n OCOR 12, - (CH 2) n NCO, - (CH _{2) n NO 2, - (} CH 2) n CN, - (CH 2) n CONR 13 R 14, - (CH 2) n NR 13 R 14, - (CH 2) n OZ, - (CH 2) n W, (—CO) ₂ O, (—CO) ₂ NR ¹⁵ composed of X ² and Y ² or X ³ and Y ³ are shown. R ¹¹ , R ¹² , R ¹³ , R ¹⁴ and R ¹⁵ are each independently a hydrogen atom, a hydrocarbon group having 1 to 20 carbon atoms, Z is a hydrocarbon group or a hydrocarbon group substituted with halogen, and W is SiR ¹⁶ _p D _3-p (R ¹⁶ is a hydrocarbon group having 1 to 10 carbon atoms, D is a halogen atom, —OCOR ¹⁶ or —OR ¹⁶ , p is an integer of 0 to 3), n is 0 to 10 Indicates an integer.

It is particularly preferable that m in the general formula (A-II) or (A-III) represents 0 or 1, and R ^{3 to} R ⁶ , X ^{2 to} X ³ , and Y ^{2 to} Y ³ represent a hydrogen atom. .

  The polymer having the structural unit represented by the general formula (A-II) or (A-III) may further contain at least one structural unit represented by the following general formula (AI).

In general formula (AI), R ^{1 to} R ² each independently represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, and X ¹ and Y ¹ are each independently a hydrogen atom, or 1 to 10 carbon atoms. hydrocarbon group, a halogen atom, a hydrocarbon group having 1 to 10 carbon atoms substituted with a halogen _{atom, - (CH 2) n COOR} 11, - (CH 2) n OCOR 12, - (CH 2) n NCO, _{- (CH 2) n NO 2} , - (CH 2) n CN, - (CH 2) n CONR 13 R 14, - (CH 2) n NR 13 R 14, - (CH 2) n OZ, - (CH _{2) n} W, or composed of X ¹ and _{^{Y 1 (-CO) 2 O,}} (- indicates a CO) ₂ NR ^15. R ¹¹ , R ¹² , R ¹³ , R ¹⁴ and R ¹⁵ are each independently a hydrogen atom, a hydrocarbon group having 1 to 20 carbon atoms, Z is a hydrocarbon group or a hydrocarbon group substituted with halogen, and W is SiR ¹⁶ _p D _3-p (R ¹⁶ is a hydrocarbon group having 1 to 10 carbon atoms, D is a halogen atom, —OCOR ¹⁶ or —OR ¹⁶ , p is an integer of 0 to 3), n is 0 to 10 Indicates an integer.

  From the viewpoint of moisture permeability reduction and adhesion between the A layer and the B layer, the cyclic polyolefin-based resin may contain 90% by mass or less of the structural unit derived from the cyclic olefin with respect to the total mass of the cyclic polyolefin-based resin. The content is preferably 30 to 85% by mass, more preferably 50 to 79% by mass, and most preferably 60 to 75% by mass. Here, the ratio of the structural unit derived from cyclic polyolefin represents the average value in cyclic polyolefin resin.

Norbornene polymer hydrides are disclosed in JP-A-1-240517, JP-A-7-196736, JP-A-60-26024, JP-A-62-19807, JP-A-2003-115767, or JP-A-2004-309799. As disclosed in No. 1, etc., a polycyclic unsaturated compound is produced by addition polymerization or metathesis ring-opening polymerization and then hydrogenation. In the norbornene-based polymer used in the present invention, R ^{3 to} R ⁶ are preferably a hydrogen atom or —CH _{3, and} more preferably a hydrogen atom from the viewpoint of low moisture permeability. X ³ and Y ³ are preferably a hydrogen atom, Cl, and —COOCH _{3, and} more preferably a hydrogen atom from the viewpoint of low moisture permeability. Other groups are appropriately selected. m is preferably 0 or 1. This norbornene-based resin is sold under the trade name Arton G or Arton F by JSR Corporation, and from Zeon Corporation, Zeonor ZF14, ZF16, Zeonex 250 or Zeonex. They are commercially available under the trade name 280 and can be used.

  Norbornene-based addition (co) polymers are disclosed in JP-A No. 10-7732, JP-T-2002-504184, U.S. Published Patent No. 200429129157A1 or WO2004 / 070463A1. It can be obtained by addition polymerization of norbornene-based polycyclic unsaturated compounds. If necessary, norbornene-based polycyclic unsaturated compounds and ethylene, propylene, butene; conjugated dienes such as butadiene and isoprene; nonconjugated dienes such as ethylidene norbornene; acrylonitrile, acrylic acid, methacrylic acid, maleic anhydride It is also possible to carry out addition polymerization with linear diene compounds such as acid, acrylic acid ester, methacrylic acid ester, maleimide, vinyl acetate and vinyl chloride. Among these, a copolymer with ethylene is preferable. This norbornene-based addition (co) polymer is marketed by Mitsui Chemicals, Inc. under the name of Apel, and has different glass transition temperatures (Tg) such as APL8008T (Tg70 ° C), APL6013T (Tg125 ° C) or APL6015T ( Grades such as Tg145 ° C). Pellets such as TOPAS 8007, 6013, and 6015 are sold by Polyplastics Co., Ltd. Further, Appear 3000 is sold by Ferrania.

  In the present invention, the glass transition temperature (Tg) of the cyclic polyolefin resin is not limited, but a cyclic polyolefin resin having a high Tg such as 150 to 250 ° C. can also be used.

  From the viewpoint of the viscosity of the composition containing the cyclic polyolefin resin and the adhesion between the A layer and the B layer, the melt flow rate (MFR) of the cyclic polyolefin resin is preferably 1 to 500 g / 10 min, and preferably 5 to 200 g / 10 min is more preferable, 40 to 200 g / 10 min is further preferable, and 100 to 200 g / 10 min is most preferable.

In order to obtain a sufficiently low moisture permeability, the content of the cyclic polyolefin resin contained in the (A) layer is preferably 70% by mass or more, based on the total solid content of the (A) layer, and 80% by mass. % Or more, more preferably 90% by mass or more.
Moreover, it is also preferable to use cyclic polyolefin-type resin independently (content of 100 mass%).

  The thickness of the layer (A) is preferably 20 μm or less, more preferably 1 μm or more and 15 μm or less, and even more preferably 3 μm or more and 10 μm or less, for satisfying the demand for thinning while satisfying a sufficiently low moisture permeability.

<Ultraviolet absorber>
The (A) layer may contain an ultraviolet absorber. By containing the ultraviolet absorber, it is possible to improve the light resistance of the optical film and to prevent deterioration of the image display member such as the polarizing plate and the liquid crystal compound of the liquid crystal display device.
Examples of the ultraviolet absorber include an oxybenzophenone compound, a benzotriazole compound, a salicylic acid ester compound, a benzophenone compound, a cyanoacrylate compound, a nickel complex compound, and a polymer ultraviolet absorbing compound containing an ultraviolet absorbing group. However, it is not limited to these. Two or more kinds of ultraviolet absorbers may be used.
When the ultraviolet absorber is contained, the content of the ultraviolet absorber is preferably 0.2 to 10% by mass, more preferably 0.5 to 7% by mass with respect to the total solid content of the layer (A). 5 mass% is more preferable.

[(B) Layer containing resin polymerized by light and / or heat having alicyclic structure in molecule]
The optical film of the present invention has a layer ((B) layer) containing a resin polymerized by light and / or heat having an alicyclic structure in the molecule.

<(B) Resin polymerized by light and / or heat having an alicyclic structure in the molecule contained in the layer>
The layer (B) includes a resin polymerized by light and / or heat having an alicyclic structure in the molecule.
A resin polymerized by light and / or heat having an alicyclic structure in the molecule has a structure similar to the cyclic structure of the cyclic polyolefin-based resin in the layer (A). (A) High affinity with resin and excellent adhesion to the layer (A), and the alicyclic structure is hydrophobic, so the water vapor transmission rate can be lowered. Even when the film thickness of the optical film is reduced, the water vapor transmission rate of the optical film Can be lowered. In addition, when the (C) hard coat layer is laminated on the (B) layer, it is considered that the interfacial mixed layer is easily formed, so that the adhesiveness with the (C) hard coat layer is also excellent.

The alicyclic structure of a resin polymerized by light and / or heat having an alicyclic structure in the molecule is preferably a cyclic aliphatic hydrocarbon group.
The alicyclic structure is preferably an alicyclic structure having 5 to 20 carbon atoms, more preferably an alicyclic structure having 8 to 16 carbon atoms, and still more preferably an alicyclic structure having 10 to 14 carbon atoms. is there.
The alicyclic structure is preferably a polycyclic structure such as bicyclic or tricyclic.
More preferably, the central skeleton of the compound described in the claims of JP-A No. 2006-215096, the central skeleton of the compound described in JP-A No. 2001-10999, or the skeleton of an adamantane derivative may be used.
Specific examples of the cyclic aliphatic hydrocarbon group include norbornyl, tricyclodecanyl, tetracyclododecanyl, pentacyclopentadecanyl, adamantyl, diamantanyl and the like.

The resin polymerized by light and / or heat having an alicyclic structure in the molecule is preferably a resin obtained by polymerizing a polymerizable compound having an alicyclic structure in the molecule by light and / or heat. Only one type of polymerizable compound having an alicyclic structure in the molecule may be used, or two or more types may be used in combination.
The polymerizable compound having an alicyclic structure in the molecule is preferably a monomer or oligomer having one or more ethylenically unsaturated double bond groups in the molecule, and is a polyfunctional monomer or oligomer having two or more. Is more preferable, and a polyfunctional monomer or oligomer having 2 or more and 4 or less is more preferable.
Examples of the ethylenically unsaturated double bond group include polymerizable functional groups such as a (meth) acryloyl group, a vinyl group, a styryl group, and an allyl group. Among them, a (meth) acryloyl group, —C (O) OCH═ CH ₂ is preferred, and a (meth) acryloyl group is more preferred.

  The polymerizable compound having an alicyclic structure in the molecule is particularly preferably a polyfunctional monomer or oligomer having two or more ethylenically unsaturated double bond groups. Due to the polyfunctional monomer or oligomer having two or more ethylenically unsaturated double bond groups, it is excellent in low moisture permeability, excellent in adhesion with the layer (A) and excellent in adhesion with the hard coat layer (C). It can be a layer. Although details are not clear, it is considered that by using a compound having an alicyclic structure in the molecule, compatibility with the cyclic polyolefin resin is improved and adhesion is improved. Moreover, surface hardness can be improved by having two or more ethylenically unsaturated double bond groups in a molecule | numerator and raising a crosslinking point density.

  The resin polymerized by light and / or heat having an alicyclic structure is a resin obtained by polymerizing a polymerizable compound having a group represented by any one of the following general formulas (I) to (V) with light and / or heat. It is preferable that it is a resin obtained by polymerizing a polymerizable compound having a group represented by the following general formula (I), (II), or (IV) with light and / or heat. A resin obtained by polymerizing a polymerizable compound having a group represented by the formula (I) or (IV) with light and / or heat is more preferable.

  In general formula (I), L and L ′ each independently represent a divalent or higher linking group. n represents an integer of 1 to 3.

  In general formula (II), L and L ′ each independently represent a divalent or higher linking group. n represents an integer of 1 to 2.

  In general formula (III), L and L ′ each independently represent a divalent or higher linking group. n represents an integer of 1 to 2.

  In general formula (IV), L and L ′ each independently represent a divalent or higher valent linking group, and L ″ represents a hydrogen atom or a divalent or higher valent linking group.

  In general formula (V), L and L ′ each independently represent a divalent or higher linking group.

In a compound having an alicyclic structure and having two or more ethylenically unsaturated double bonds in the molecule, the alicyclic structure and a group having an ethylenically unsaturated double bond are bonded via a linking group. A compound is preferred.
As the linking group, a single bond, an alkylene group having 1 to 6 carbon atoms which may be substituted, an amide group which may be substituted at the N position, a carbamoyl group which may be substituted at the N position, an ester group, Examples include oxycarbonyl groups, ether groups, and the like, and groups obtained by combining these.

These compounds include, for example, polyols such as diols and triols having an alicyclic structure, and carboxylic acids, carboxylic acid derivatives, epoxy derivatives, isocyanates of compounds having (meth) acryloyl groups, vinyl groups, styryl groups, allyl groups, and the like. It can be easily synthesized by a one-step or two-step reaction with a nate derivative or the like.
Preferably, compounds such as (meth) acrylic acid, (meth) acryloyl chloride, (meth) acrylic anhydride, glycidyl (meth) acrylate, and compounds described in WO2012 / 00316A (eg, 1,1-bis ( (Acryloxymethyl) ethyl isocyanate) can be synthesized by reacting with a polyol having an alicyclic structure.

  The polymerizable compound having a group represented by the general formula (I) is preferably a compound represented by the following general formula (A) or (B).

  In general formula (A) and general formula (B), R1 represents a hydrogen atom or a C1-C3 alkyl group, Preferably, a hydrogen atom, a methyl group, and an ethyl group are represented. R2 represents an alkylene group having 1 to 5 carbon atoms or an alkylene oxide group, preferably a methylene group, an ethylene group, a methylene oxide group, or an ethylene oxide group. R3 represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and preferably represents a hydrogen atom, a methyl group, or an ethyl group. n represents an integer of 1 or 2.

  In the present invention, preferred specific examples (M-1 to M-7) of the compound having an alicyclic structure and an ethylenically unsaturated double bond group are shown, but the present invention is not limited thereto.

  (B) The content of the resin polymerized by light and / or heat having an alicyclic structure in the molecules contained in the layer is sufficient to obtain a sufficient surface hardness, so that the total solid content of the (B) layer is It is preferably 70% by mass or more, more preferably 70% by mass or more and 99% by mass or less, and still more preferably 80% by mass or more and 98% by mass or less.

The thickness of the layer (B) is preferably 20 μm or less, more preferably 2 μm or more and 16 μm or less, and even more preferably 4 μm or more and 12 μm or less, for the reason that the requirement for thinning is satisfied while obtaining sufficient surface hardness.
In the optical film of the present invention, the film thickness of the (A) layer is preferably 20 μm or less, and the film thickness of the (B) layer is preferably 20 μm or less.

  The layer (B) may contain a polymerization initiator.

[(C) Hard coat layer]
The optical film of the present invention preferably further comprises (C) a hard coat layer (also referred to as “C layer”), and more preferably comprises (A) layer, (B) layer, and (C) layer in this order. preferable.
Here, the hard coat layer means that each optical film having a hard coat layer is conditioned for 2 hours under the conditions of 25 ° C. and a relative humidity of 60%, and then using a test pencil (3H) defined by JIS S 6006. In accordance with the pencil hardness evaluation method stipulated by JIS K 5400, the hard coat layer surface is scratched 5 times with a pencil of each hardness using a weight of 500 g, and the number of times that no scar remains is 3 times or more, preferably The layer is 4 times or more, more preferably 5 times.
The film thickness of the (C) layer is more preferably 3 μm or more and 20 μm or less, and further preferably 4 μm or more and 12 μm or less. Sufficient hardness is obtained when it is 3 μm or more, and it is preferable in terms of brittleness when it is 20 μm or less.

The hard coat layer preferably contains a resin polymerized by light and / or heat, preferably contains 70% by mass or more of a resin polymerized by light and / or heat with respect to the total solid content of the hard coat layer, 75 More preferably, it is contained in an amount of from 98% by mass to 98% by mass, and more preferably from 80% by mass to 95% by mass. The resin polymerized by light and / or heat of the hard coat layer is preferably a resin obtained by polymerizing a polymerizable compound polymerized by light and / or heat by light and / or heat.
As the polymerizable compound that is polymerized by light and / or heat, a compound (polyfunctional monomer) having a linear or branched structure and having two or more polymerizable groups is preferable.
The polymerizable group possessed by the polymerizable compound that is polymerized by light and / or heat is preferably an ethylenically unsaturated double bond group, an epoxy group, an oxetanyl group, or an alkoxysilyl group.
Examples of the ethylenically unsaturated double bond group include polymerizable functional groups such as a (meth) acryloyl group, a vinyl group, a styryl group, and an allyl group. Among them, a (meth) acryloyl group, —C (O) OCH═ CH ₂ is preferred, and a (meth) acryloyl group is more preferred.

The polymerizable compound that is polymerized by light and / or heat is preferably a compound containing an ethylenically unsaturated double bond group or a compound containing a ring-opening polymerizable group, and these compounds may be used alone or in combination. it can.
Preferred examples of the compound containing an ethylenically unsaturated double bond group include ethylene glycol diacrylate, trimethylolpropane triacrylate, ditrimethylolpropane tetraacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, Polyacrylates of polyols such as dipentaerythritol hexaacrylate; epoxy acrylates such as diacrylate of bisphenol A diglycidyl ether, diacrylate of hexanediol diglycidyl ether; hydroxyl-containing acrylates such as polyisocyanate and hydroxyethyl acrylate Urethane acrylate obtained by the reaction can be mentioned as a preferred compound. Moreover, as a commercially available compound, EB-600, EB-40, EB-140, EB-1150, EB-1290K, IRR214, EB-2220, TMPTA, TMPTMA (above, Daicel UCB Co., Ltd. product), UV -6300, UV-1700B (manufactured by Nippon Synthetic Chemical Industry Co., Ltd.) and the like.

  Preferred examples of the compound containing a ring-opening polymerizable group include ethylene glycol diglycidyl ether, bisphenol A diglycidyl ether, trimethylol ethane triglycidyl ether, trimethylol propane triglycidyl ether, glycerol triglycidyl ether as glycidyl ethers. Triglycidyl trishydroxyethyl isocyanurate, sorbitol tetraglycidyl ether, pentaerythritol tetraglycyl ether, polyglycidyl ether of cresol novolac resin, polyglycidyl ether of phenol novolac resin, etc. Celoxide 2021P, Celoxide 2081, Epoxide GT-301, Epolide GT-401, EHPE3150CE (above, Oxetane, OXT-121, OXT-221, OX-SQ, PNOX-1009 (above, manufactured by Toagosei Co., Ltd.), etc. Can be mentioned. In addition, a polymer of glycidyl (meth) acrylate or a copolymer of a monomer that can be copolymerized with glycidyl (meth) acrylate may be used for the hard coat layer.

  The hard coat layer may be a layer having other functions in addition to the hard coat property. Examples of other functions include antiglare properties, antistatic properties, and ultraviolet absorption properties. That is, the hard coat layer may contain components for imparting other functions (for example, light scattering particles, antistatic agents, ultraviolet absorbers, etc.).

  The thickness of the hard coat layer is preferably 10 μm or less, more preferably 2 μm or more and 8 μm or less, and even more preferably 3 μm or more and 6 μm or less from the viewpoint of satisfying the demand for thinning while ensuring sufficient hardness. .

<Layer structure of optical film>
The optical film of the present invention has (A) a layer containing cyclic polyolefin resin light, and (B) a layer containing a resin polymerized by light and / or heat having an alicyclic structure in the molecule.
The optical film of the present invention further has (C) a hard coat layer, and preferably has (A) layer, (B) layer, and (C) layer in this order.
The (A) layer and the (B) layer are preferably laminated directly without interposing other layers.
The (B) layer and the (C) layer are preferably laminated directly without interposing other layers.
Further, the optical film of the present invention has an antireflection layer (low refractive index layer, medium refractive index layer, high refractive index layer, etc.) on the (C) layer (on the side opposite to the (B) layer side). You may provide the layer etc. which adjusted the rate. Specific preferred layer structures of the optical film of the present invention are shown below.
-(A) layer / (B) layer-(A) layer / (B) layer / (C) layer-(A) layer / (B) layer / (C) layer / low refractive index layer-(A) layer / (B) layer / (C) layer / high refractive index layer / low refractive index layer (A) layer / (B) layer / (C) layer / medium refractive index layer / high refractive index layer / low refractive index layer As the medium refractive index layer, the high refractive index layer, and the low refractive index layer, JP-A-2006-17870, JP-A-2006-30881, JP-A-2007-298974, JP-A-2011-136503, JP-A-2012-159692 Although what is described in etc. can be used suitably, it is not limited to this.

(Water vapor transmission rate of optical film)
The moisture permeability of the optical film of the present invention is measured under the conditions of 40 ° C. and 90% relative humidity based on JIS Z-0208.
The moisture permeability of the optical film of the present invention is preferably less than 200 g / m ² / day, more preferably less than 100 g / m ² / day, and still more preferably less than 50 g / m ² / day. Is particularly preferably less than 30 g / m ² / day, and even more preferably less than 10 g / m ² / day.

[Method for producing optical film]
Examples of the method for producing an optical film of the present invention include (A) a method of producing a layer containing a cyclic polyolefin resin by melt film formation, and a method of producing a layer by solution film formation.
When the film thickness of the layer (A) is 20 μm or less, it is easy to carry by forming a film on the support, and it is possible to suppress the generation of folds and wrinkles during conveyance. From the viewpoint that a film and a polarizing plate can be produced and an optical film having excellent adhesion between the (A) layer and the (B) layer can be produced, solution casting is preferred.

<Solution casting>
(A) It is preferable that the manufacturing method of the optical film of this invention when producing the layer containing cyclic polyolefin resin by solution casting has the following process (a)-(f).
(A) The process of apply | coating the 1st solution containing cyclic polyolefin resin and a 1st solvent on a support body, and forming a 1st application layer (b) The 1st contained in the above-mentioned 1st application layer (C) Applying a second solution containing a polymerizable compound having an alicyclic structure in the molecule and a second solvent on the layer (A) described above. (D) The step of drying the second solvent contained in the second coating layer (e) The molecule contained in the second coating layer has an alicyclic structure. A step of obtaining a resin having an alicyclic structure in a molecule by polymerizing a polymerizable compound with light and / or heat to obtain a layer (B) (f) including the above-described layers (A) and (B) Step of peeling the laminate from the above-mentioned support

The (A) layer is obtained by drying the first solvent contained in the first coating layer in the step (b). However, the first solvent may remain in the layer (A) as long as the problem of the present invention can be solved, and the step (b) may not be included.
The layer (B) is obtained by drying the second solvent in the step (d), and the polymerizable compound having an alicyclic structure in the molecule contained in the second coating layer in the step (e) by light and / or heat. It is obtained by polymerizing. However, the second solvent may remain in the layer (B) as long as the problem of the present invention can be solved.

  It is preferable to have the aforementioned steps (a) to (f) in this order.

Moreover, it is preferable that the manufacturing method of the optical film of this invention has the following (g) process further, and after (g) process is performed before (f) process is performed after performing (c) process. preferable.
(G) The process of apply | coating the solution for hard-coat layer formation on a 2nd application layer or the (B) layer, and forming a hard-coat layer.

[Step (a)]
(A) A process is a process of apply | coating the 1st solution containing cyclic polyolefin resin and a 1st solvent on a support body, and forming a 1st application layer.

<Support>
The support is preferably a support made of a polymer film.
Examples of the polymer constituting the polymer film include polyesters such as polyethylene terephthalate and cellulose esters such as cellulose triacetate.

  The cyclic polyolefin resin contained in the first solution in the step (a) is as described in the description of the layer (A).

<First solvent>
The first solvent is a solvent that can dissolve or disperse the cyclic polyolefin-based resin.
The first solvent may include only one type of solvent or two or more types of solvents.
The first solvent is preferably an organic solvent, and is a chain aliphatic hydrocarbon solvent such as n-pentane, n-hexane, n-heptane, liquid paraffin, mineral spirit, cyclopentane, cyclohexane, methylcyclohexane, Alicyclic hydrocarbon solvents such as dimethylcyclohexane, trimethylcyclohexane, ethylcyclohexane, diethylcyclohexane, decahydronaphthalene, dicycloheptane, tricyclodecane, hexahydroindene and cyclooctane, and aromatic carbonization such as benzene, toluene and xylene Hydrogen solvents, hydrocarbon solvents having alicyclic and aromatic rings such as indene and tetrahydronaphthalene, nitrogen-containing hydrocarbon solvents such as nitromethane, nitrobenzene and acetonitrile, diethyl ether, tetrahydrofuran and the like Oxygen-containing hydrocarbon solvents, chlorinated solvents such as dichloromethane and chloroform, methanol, ethanol, isopropanol, n-butyl alcohol, cyclohexyl alcohol, 2-ethyl-1-hexanol, 2-methyl-1-hexanol, 2-methoxyethanol Alcohol solvents such as 2-propoxyethanol, 2-butoxyethanol and diacetone alcohol, carbonate solvents such as dimethyl carbonate, diethyl carbonate, diisopropyl carbonate, methyl ethyl carbonate, methyl n-propyl carbonate, ethyl formate, formic acid Propyl, pentyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, ethyl 2-ethoxypropionate, methyl acetoacetate, acetate Esters such as ethyl acetate, methyl 2-methoxyacetate, methyl 2-ethoxyacetate, ethyl 2-ethoxyacetate, ethylene glycol ethyl ether, ethylene glycol isopropyl ether, ethylene glycol butyl ether, propylene glycol methyl ether, dibutyl ether, dimethoxyethane , Ether solvents such as diethoxyethane, tetrahydrofuran, anisole, phenetole, acetone, 1,2-diacetoxyacetone, acetylacetone, methyl ethyl ketone, diethyl ketone, dipropyl ketone, diisobutyl ketone, cyclopentanone, cyclohexanone, methylcyclohexanone, methyl Examples include ketone solvents such as isobutyl ketone, 2-octanone, 2-pentanone, and 2-hexanone. It is preferable to use at least one of them.

  The first solution may contain an ultraviolet absorber as described in the description of the layer (A).

  From the viewpoint of obtaining a good planar film, the solid content concentration of the first solution is preferably 4% by mass to 40% by mass, more preferably 6% by mass to 30% by mass, and 8% by mass. It is still more preferable that it is% -20 mass%.

<Application method>
Examples of the application method of the first solution include the following methods.
Dip coating method, air knife coating method, curtain coating method, roller coating method, wire bar coating method, gravure coating method and extrusion coating method (die coating method) (see US Pat. No. 2,681,294), micro gravure coating method, etc. Known methods are used, and among them, the micro gravure coating method and the die coating method are preferable.

[Step (b)]
(B) A process is a process of drying the 1st solvent contained in the above-mentioned 1st application layer, and obtaining (A) layer.
However, the step (c) may be performed without going through the step (b).
As the drying method, heat treatment is preferable, heat treatment is preferably performed at an atmospheric temperature of 60 to 200 ° C, and heat treatment is more preferably performed at 80 to 160 ° C.
The drying time is preferably a treatment for 30 seconds to 10 minutes, more preferably a treatment for 1 minute to 5 minutes.

[(C) Step]
(C) A process applies the 2nd solution containing the polymeric compound which has an alicyclic structure in a molecule | numerator, and the 2nd solvent on the 1st application layer provided at the above-mentioned (a) process. This is a step of forming a second coating layer.

  The polymerizable compound having an alicyclic structure in the molecule contained in the second solution in the step (c) is as described in the description of the layer (B).

<Second solvent>
The second solvent is a solvent that can dissolve or disperse the polymerizable compound having an alicyclic structure in the molecule.
The second solvent may include only one type of solvent or two or more types of solvents.
The second solvent is preferably an organic solvent, taking into consideration the solubility of the polymerizable compound having an alicyclic structure in the molecule, the drying property during coating, the dispersibility of the translucent particles, and the like. Can be used. Examples of the organic solvent include dibutyl ether, dimethoxyethane, diethoxyethane, propylene oxide, 1,4-dioxane, 1,3-dioxolane, 1,3,5-trioxane, tetrahydrofuran, anisole, phenetole, dimethyl carbonate, and methyl carbonate. Ethyl, diethyl carbonate, acetone, methyl ethyl ketone (MEK), diethyl ketone, dipropyl ketone, diisobutyl ketone, cyclopentanone, cyclohexanone, methylcyclohexanone, ethyl formate, propyl formate, pentyl formate, methyl acetate, ethyl acetate, propyl acetate, propion Acid methyl, ethyl propionate, γ-ptyrolactone, methyl 2-methoxyacetate, methyl 2-ethoxyacetate, ethyl 2-ethoxyacetate, ethyl 2-ethoxypropionate, 2-methoxy Tanol, 2-propoxyethanol, 2-butoxyethanol, 1,2-diacetoxyacetone, acetylacetone, diacetone alcohol, methyl acetoacetate, methyl acetoacetate and other methyl alcohol, ethyl alcohol, isopropyl alcohol, n-butyl alcohol, cyclohexyl alcohol , Isobutyl acetate, 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, ethylcyclohexane, benzene, toluene Xylene and the like, and can be used singly or in combination of two or more.
Among the above solvents, it is preferable to use at least one of dimethyl carbonate, methyl acetate, ethyl acetate, methyl ethyl ketone, acetylacetone, and acetone, more preferably dimethyl carbonate or methyl acetate, and methyl acetate is used. It is particularly preferred.

<Polymerization initiator>
The second solution preferably contains a polymerization initiator in order to polymerize a polymerizable compound having an alicyclic structure in the molecule by light and / or heat in the step (e).
As polymerization initiators, acetophenones, benzoins, benzophenones, phosphine oxides, ketals, anthraquinones, thioxanthones, azo compounds, peroxides, 2,3-dialkyldione compounds, disulfide compounds, fluoroamines Examples thereof include 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 polymerization initiator are described in paragraphs [0133] to [0151] of JP-A-2009-098658, and can be suitably used in the present invention as well. .

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

  Commercially available photocleavable photoradical polymerization initiators include “Irgacure 651”, “Irgacure 184”, “Irgacure 819”, “Irgacure 907” manufactured by BASF (former Ciba Specialty Chemicals), “Irgacure 1870” (CGI-403 / Irgacure 184 = 7/3 mixed initiator), “Irgacure 500”, “Irgacure 369”, “Irgacure 1173”, “Irgacure 2959”, “Irgacure 4265”, “Irgacure 4263”, “Irgacure 127”, “OXE01”, etc .; “Kaya Cure DETX-S”, “Kaya Cure BP-100”, “Kaya Cure BDK”, “Kaya Cure BTX”, “Kaya Cure BMS”, “Kaya Cure 2” manufactured by Nippon Kayaku Co., Ltd. -EAQ "," Kayaki " “AraQ”, “Kayacure CPTX”, “Kayacure EPD”, “Kayacure ITX”, “Kayacure QTX”, “Kayacure BTC”, “Kayacure MCA”, etc .; “Esacure (KIP100F, KB1, EB3, BP, BP, manufactured by Sartomer) X33, KTO46, KT37, KIP150, TZT) "and the like, and combinations thereof are preferable examples.

  The reason why the content of the polymerization initiator in the second solution is set so that the polymerizable compound having an alicyclic structure is polymerized in the molecule contained in the second solution and the starting point is not increased excessively. Therefore, 0.2 to 10% by mass is preferable and 1 to 5% by mass is more preferable with respect to the total solid content in the second solution.

  As the coating method in step (c), the same method as the coating method in step (a) described above can be used.

[Step (d)]
(D) A process is a process of drying the 2nd solvent contained in the above-mentioned 2nd application layer.
As a drying method, heat treatment is preferable, heat treatment is preferably performed at an ambient temperature of 40 to 160 ° C, and heat treatment is more preferably performed at 50 to 120 ° C.
The drying time is preferably a treatment for 30 seconds to 10 minutes, more preferably a treatment for 1 minute to 5 minutes.

[(E) Process]
In step (e), a polymerizable compound having an alicyclic structure in the molecule contained in the second coating layer provided in step (c) is polymerized by light and / or heat to alicyclic in the molecule. This is a step of obtaining a (B) layer by obtaining a resin having a structure.

(Polymerization by heat)
When a thermopolymerizable compound is used as the polymerizable compound having an alicyclic structure in the molecule, the polymerization temperature is preferably 60 to 200 ° C, more preferably 80 to 130 ° C, and most preferably 80 to 110 ° C. is there. A low temperature is preferred when the support is prone to degradation at high temperatures. The time required for the thermal polymerization is preferably 30 seconds to 60 minutes, more preferably 1 minute to 20 minutes. For example, thermal polymerization can be used when a compound having an epoxy group and / or oxetanyl group and a thermal acid generator are used as a polymerization initiator.

(Polymerization by light)
When a photopolymerizable compound is used as the polymerizable compound having an alicyclic structure in the molecule, it can be polymerized by irradiation with ionizing radiation. Furthermore, it is effective to perform polymerization by combining heat treatment before irradiation, simultaneously with irradiation or after irradiation. For example, photopolymerization is used when a compound having an ethylenically unsaturated double bond group and a photo radical initiator are used, or when a compound having an epoxy group and / or an oxetanyl group and a photo acid generator are used as a polymerization initiator. it can.
Although the pattern of some manufacturing processes is shown below, it is not limited to these.
Before irradiation → At the same time as irradiation → After irradiation (-indicates that heat treatment is not performed)
(1) Heat treatment → Ionizing radiation irradiation → −
(2) Heat treatment → Ionizing radiation irradiation → Heat treatment (3) − → Ionizing radiation irradiation → Heat treatment In addition, a step of performing heat treatment simultaneously with ionizing radiation irradiation is also preferable.

(Heat treatment)
In the present invention, as described above, heat treatment is preferably performed in combination with irradiation with ionizing radiation. The heat treatment is not particularly limited as long as it does not damage the support and the constituent layers including each layer formed by coating, but is preferably 60 to 200 ° C, more preferably 80 to 130 ° C, and most preferably 80 to 110 ° C. It is.

  By increasing the temperature, the distribution of each component in the coating film can be adjusted, and the photopolymerization reaction can be controlled. The time required for the heat treatment varies depending on the molecular weight of the component used, interaction with other components, viscosity, etc., but is 30 seconds to 24 hours, preferably 60 seconds to 5 hours, and most preferably 3 minutes to 30 minutes.

  Although there is no limitation in particular in the method of setting the film surface temperature of a film to desired temperature, The method of heating a roll and contacting a film, the method of spraying heated nitrogen, irradiation of far infrared rays or infrared rays, etc. are preferable. A method described in Japanese Patent No. 2523574 may also be used, in which hot water or steam is passed through a rotating metal roll and heated. On the other hand, at the time of irradiation of ionizing radiation described below, when the film surface temperature of the film rises, a method of cooling the roll and bringing it into contact with the film can be used.

(Ionizing radiation irradiation conditions)
The film surface temperature during irradiation with ionizing radiation is not particularly limited, but is generally 20 to 200 ° C., preferably 20 to 150 ° C., and most preferably 40 to 120 ° C., from the viewpoint of handling properties and in-plane performance uniformity. It is. If the film surface temperature is not more than this upper limit value, the fluidity of the low-molecular component in the binder is excessively increased and the surface state is not deteriorated, and the problem that the support is damaged by heat does not occur. Moreover, if it is more than this lower limit, since advancing of a polymerization reaction is enough and the adhesiveness of a coating film will become favorable, it is preferable.

There is no restriction | limiting in particular about the kind of ionizing radiation, Although an X-ray, an electron beam, an ultraviolet-ray, visible light, infrared rays etc. are mentioned, It is preferable to use an ultraviolet-ray. For example, if the coating film is an ultraviolet polymerizable, preferably polymerized by an irradiation amount of 10mJ / cm ² ~1000mJ / cm ² by an ultraviolet lamp. At the time of irradiation, the aforementioned energy may be applied at once, or irradiation may be performed in divided portions. In particular, from the viewpoint of reducing the performance variation in the surface of the coating film, it is also preferable to irradiate the ultraviolet rays by dividing them into 2 to 8 times.

(Oxygen concentration)
The oxygen concentration in the process at the time of ionizing radiation irradiation is preferably 3% by volume or less, more preferably 1% by volume or less, still more preferably 0.1% by volume or less, and most preferably 0.03% by volume. % Or less. In contrast to the step of irradiating ionizing radiation at an oxygen concentration of 3% by volume or less, a step of maintaining in an atmosphere at an oxygen concentration of 3% by volume or less can be provided immediately before or immediately after. By doing so, it is possible to sufficiently promote the polymerization and to form a film having excellent surface hardness and coating film adhesion.

  The heat treatment step before, simultaneously with or after the irradiation with ionizing radiation can be performed in the atmosphere, but it is also preferable to decrease the oxygen concentration as in the ionizing radiation irradiation. In particular, when the thermal stability of a polymerization initiator, a polymerizable compound, or the like is insufficient, the strength of the film after the completion of the entire polymerization process can be kept strong by performing a heat treatment while reducing the oxygen concentration.

  As a means for reducing the oxygen concentration, it is preferable to replace the atmosphere (nitrogen concentration of about 79% by volume, oxygen concentration of about 21% by volume) with another inert gas, and particularly preferably with nitrogen (nitrogen purge). It is. By carrying it in an atmosphere with a low oxygen concentration (0.1% by volume) before the step of irradiating with ionizing radiation, the oxygen concentration inside the coating film surface and inside can be effectively reduced, and the polymerization is promoted. can do.

[Step (f)]
(F) A process is a process of peeling the laminated body containing the above-mentioned (A) layer and (B) layer from the above-mentioned support body.

[Step (g)]
(G) A process is a process of apply | coating the solution for hard-coat layer formation on a 2nd application layer or (B) layer, and forming a hard-coat layer.
The hard coat layer forming solution preferably contains a polymerizable compound described in the description of the hard coat layer and a solvent capable of dissolving or dispersing the polymerizable compound. Examples of the solvent include the same solvents as the second solvent.
The application method of the hard coat layer forming solution is the same as the application method of the first solution.
The hard coat layer is preferably formed as a resin by polymerizing a polymerizable compound in the hard coat layer forming solution with light and / or heat. The polymerization method is the same as the polymerization of a polymerizable compound having an alicyclic structure in the molecule contained in the second solution.

<Melting film formation>
(A) The production method of the optical film of the present invention in the case of producing a layer containing a cyclic polyolefin resin by melt film formation is to form a cyclic polyolefin resin by a known melt film formation method, and then the above-mentioned ( It is preferable to carry out steps c), (d), (e), and (f).
Moreover, it is preferable to have (g) process similarly to the above-mentioned.

[Polarizer]
The polarizing plate of this invention is a polarizing plate which has a polarizer and the above-mentioned optical film of this invention, Comprising: It has a polarizer, (A) layer, and (B) layer in this order.
FIG. 1 shows an example of the polarizing plate of the present invention. The polarizing plate of FIG. 1 has a polarizer, (A) layer, (B) layer, and (C) layer in this order.
The optical film of the present invention can be used as a protective film for a polarizing plate. When using as a protective film for polarizing plates, the production method of a polarizing plate is not specifically limited, It can produce by a general method. There is a method in which the optical film of the present invention is alkali-treated and bonded to a polarizer. Instead of alkali treatment, easy adhesion processing as described in JP-A-6-94915 and JP-A-6-118232 may be performed. Further, surface treatment such as corona treatment may be performed. The bonding surface of the optical film with the polarizer is preferably a layer containing (A) a cyclic polyolefin resin.
Examples of the adhesive used to bond the protective film treated surface and the polarizer include polyvinyl alcohol adhesives such as polyvinyl alcohol and polyvinyl butyral, vinyl latexes such as butyl acrylate, and the like.

  You may have a polarizing plate protective film in the surface on the opposite side to the surface which has the optical film of this invention of a polarizer. The polarizing plate protective film is not particularly limited, and for example, a cyclic polyolefin resin film, a cellulose acylate film, or the like can be used.

  The optical film of the present invention is preferably used as a polarizing plate protective film on the viewing side (the side far from the liquid crystal cell) of the viewing side polarizing plate of the liquid crystal display device.

  In the polarizing plate of the present invention, the film thickness is preferably 40 μm or less, more preferably 5 to 30 μm, still more preferably 10 to 25 μm, from the viewpoint of thinning.

(Polarizer)
The polarizer used for the polarizing plate is preferably a polarizer obtained by dyeing a polyvinyl alcohol resin with iodine or a dichroic dye.
The thickness of the polarizer is preferably 10 μm or less, more preferably 1 to 10 μm, and still more preferably 2 to 6 μm from the viewpoint of thinning.
For a method for manufacturing a polarizer, for example, Japanese Patent No. 4691205 can be referred to as a method for manufacturing a thin polarizer.

[Production method of polarizing plate]
The manufacturing method of the polarizing plate of this invention is (A) of the laminated body (A) of the laminated body (A) layer and (B) layer which were peeled in the (f) process of the manufacturing method of the above-mentioned optical film. It is preferable to perform a surface treatment such as corona treatment on the layer, and a step of bonding a separately prepared polarizer and the layer (A).

<Image display device>
The image display device of the present invention includes the optical film of the present invention or the polarizing plate of the present invention.
The image display device is preferably a liquid crystal display device. As the liquid crystal display device, TN, IPS, FLC, AFLC, OCB, STN, ECB, VA and HAN mode liquid crystal display devices are preferable, and TN, OCB, IPS and VA mode liquid crystal display devices are more preferable. In addition, a display mode in which the above display mode is oriented and divided has been proposed. The optical film or polarizing plate of the present invention is effective in any display mode liquid crystal display device. Further, it is effective in any of a transmissive, reflective, and transflective liquid crystal display device.

  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]
((A) Preparation of cyclic polyolefin resin-containing layer forming composition)
<(A) Layer forming composition A1>
After mixing the following components, the mixture was charged into a glass separable flask equipped with a stirrer, stirred at room temperature for 24 hours, and then filtered through a polypropylene depth filter having a pore size of 20 μm to obtain (A) layer forming composition A1. It was.

[Composition of A layer forming composition A1]
APEL6015T 9.8 parts by mass UV-1 0.2 parts by mass Cyclohexane 90 parts by mass

<(A) Layer forming compositions A2 to A7>
(A) Layer forming compositions A2 to A7 were obtained in the same manner as (A) layer forming composition A1, except that each component was changed as shown in Table 1 below.

Hereinafter, the compounds used will be described. The following general formulas (A-IV) and (A-V) both contain structural units of the general formula (A-II).
APL6015T: Cyclic polyolefin resin represented by the following general formula (A-IV) (manufactured by Mitsui Chemicals, Inc.)
Content rate of structural unit derived from ethylene (X): 19% by mass
Content of structural unit derived from cyclic olefin (Y): 81% by mass
MFR: 10g / 10min
APL8008T: Cyclic polyolefin resin represented by the following general formula (A-IV) (manufactured by Mitsui Chemicals, Inc.)
Content rate of structural unit derived from ethylene (X): 38% by mass
Content of structural unit derived from cyclic olefin (Y): 62% by mass
MFR: 15g / 10min

TOPAS 5013: Cyclic polyolefin resin represented by the following general formula (A-V) (manufactured by Polyplastics Co., Ltd.)
Content rate of structural unit derived from ethylene (X): 23% by mass
Content of structural unit derived from cyclic olefin (Y): 77% by mass
MFR: 49g / 10min

・ ARTON R5000: (manufactured by JSR Corporation)
This is a resin having the following repeating units (the ratio of repeating units is a molar ratio), and includes a structural unit represented by the general formula (A-III).

UV-1: a compound represented by the following structural formula

X-1: Compound represented by the following structural formula

((B) Preparation of resin-containing layer-forming composition polymerized by light and / or heat having an alicyclic structure in the molecule)
<(B) Layer forming composition B1>
After mixing the following components, the mixture was placed in a glass separable flask equipped with a stirrer, stirred at room temperature for 30 minutes, and then filtered through a polypropylene depth filter with a pore size of 5 μm to obtain (B) layer forming composition B1. It was.
[(B) Composition of layer forming composition B1]
DCP 28.8 parts by mass Irgacure 907 1.2 parts by mass Cyclohexane 49 parts by mass Toluene 21 parts by mass

<(B) Layer forming composition B2>
(B) A layer forming composition B2 was obtained in the same manner as the (B) layer forming composition B1, except that the DCP used in the layer forming composition B1 was changed to A-DCP. .

<(B) Layer forming composition B3>
(B) Layer forming composition B3 was obtained in the same manner as (B) layer forming composition B1, except that the DCP used in layer forming composition B1 was changed to ADDA.

  Hereinafter, the compounds used will be described.

DCP: Tricyclodecane dimethanol dimethacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd.)
This is a compound corresponding to the aforementioned exemplary compound M-4.

A-DCP: Tricyclodecane dimethanol diacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd.)
This is a compound corresponding to the aforementioned exemplary compound M-5.

ADDA: 1,3-adamantane dimethanol diacrylate This is a compound corresponding to the aforementioned exemplary compound M-7.

((C) Preparation of composition for forming hard coat layer)
After mixing each component of the following composition, it filtered with the polypropylene filter with the hole diameter of 30 micrometers, and prepared the coating liquid for (C) hard-coat layers.

* 1: "UV1700B" (manufactured by Nihon Gosei)
* 2: Irgacure 184 (manufactured by BASF (formerly Ciba Specialty Chemicals))

(Preparation of optical film 1)
On the translucent support (cellulose triacetate (TAC): TD80UL manufactured by Fuji Film Co., Ltd.), the slot die described in Example 1 of JP-A-2006-122889 is applied to the composition (A) for forming the layer (A) described above. With the used die coating method, it apply | coated so that the film thickness after drying might be set to 10 micrometers on conditions with a conveyance speed of 10 m / min, and it was made to dry at 30 degreeC for 1 minute.

Subsequently, the (B) layer forming composition B1 was applied on the (A) layer by the same method so that the film thickness after drying was 5 μm, and dried at 120 ° C. for 5 minutes. Thereafter, using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) with an oxygen concentration of about 0.01% by volume under a nitrogen purge, ultraviolet rays having an illuminance of 400 mW / cm ² and an irradiation amount of 300 mJ / cm ² are used. Irradiated.
Subsequently, (C) the composition for forming a hard coat layer was applied on the (B) layer by a microgravure coating method under the condition of a conveyance speed of 30 m / min. After drying at 60 ° C. for 150 seconds, using a 160 W / cm air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) while purging with nitrogen (oxygen concentration of 0.5 vol% or less), an illuminance of 400 mW / cm ² , An ultraviolet ray having an irradiation amount of 150 mJ / cm ² was irradiated to form a (C) hard coat layer having a thickness of 5 μm.
Subsequently, the laminate of the (A) layer, the (B) layer, and the (C) layer was peeled from the TAC support.
Thus, the optical film 1 which has a (A) layer, a (B) layer, and a (C) layer in this order was produced.

(Preparation of optical films 2 to 8)
In the production of the optical film 1, (A) the composition for forming a layer, (B) the composition for forming a layer and (C) the types of the composition for forming a layer, and the film thickness of each layer are changed as shown in Table 3. Produced optical films 2 to 8 in the same manner.

(Production of optical films 9 to 10)
In the production of the optical film 1, the optical film 9 was similarly prepared except that (A) the type and thickness of the layer forming composition were changed as shown in Table 3, and the (B) layer and (C) layer were not provided. To 10 were produced.

(Preparation of optical film 11)
(A) Layer forming composition A7 was melted at 280 ° C. to obtain an optical film 11 with a film thickness of 10 μm.

(Preparation of optical film 12)
(A) After the layer forming composition A7 was melted at 280 ° C. and the film thickness was 10 μm, the layers (B) and (C) were formed in the same manner as the optical film 1, and the optical film 12 was Produced.

(Preparation of optical film 13)
(A) Layer forming composition A7 was melted at 280 ° C. so that the film thickness became 10 μm, and one surface was subjected to corona treatment under the condition of 1500 W · min / m ² . An optical film 13 was obtained by forming the composition for forming a layer (C) in the same manner as the optical film 1 on the surface subjected to the corona treatment.

(Preparation of optical film 14)
(A) Layer forming composition A7 was melted at 280 ° C. to form a film thickness of 40 μm to obtain optical film 14.

(Preparation of optical film 15)
(A) Layer forming composition A7 was melted at 280 ° C. so that the film thickness was 40 μm, and one surface was subjected to corona treatment under the condition of 1500 W · min / m 2. An optical film 15 was obtained by forming the (C) layer-forming composition on the surface subjected to the corona treatment described above in the same manner as the optical film 1.

[Evaluation of optical film]
The produced optical films 1 to 8, 12, 13, and 15 were subjected to the following physical property measurement and evaluation.

(Pencil hardness evaluation)
Each optical film having a hard coat layer is conditioned at 25 ° C. and a relative humidity of 60% for 2 hours, and then, using a test pencil (3H) defined by JIS S 6006, the surface of the hard coat layer is According to the pencil hardness evaluation method prescribed by JIS K 5400, scratching was repeated 5 times with a pencil of each hardness using a 500 g weight, and the number of times that no scar was left was counted. It is acceptable if the number of times that no scar remains is 3 or more.

(Evaluation of adhesion of hard coat layer)
The adhesion evaluation of the hard coat layer was performed by the following method.
A cross cut test according to JIS K 5600 was conducted. Specifically, eleven notches were made vertically and horizontally at intervals of 1 mm on the surface of the hard coat layer of the optical film to make 100 1 mm square grids. A transparent pressure-sensitive adhesive tape (manufactured by Nichiban Co., Ltd., Cellotape (registered trademark) CT-15S) was attached on this, and the peeled off and quickly peeled off part was evaluated by visual observation. Samples for measurement were evaluated after conditioning for 2 hours or more in a room at a temperature of 25 ° C. and a humidity of 60% before the adhesion evaluation.
Adhesiveness A: Peeling location 0 to 10 squares Adhesiveness B: Peeling location 11 to 49 squares Adhesiveness C: Peeling location 50 to 99 squares Adhesiveness D: Peeling location 100 squares or more (all parts pasted with tape)
A or B in the above evaluation is an acceptable level.

(Surface evaluation)
Each optical film was spread on a smooth table with a length of 2 m, and the surface shape was visually evaluated and judged according to the following criteria.
A: In-plane wrinkles and sagging are not visible and acceptable B: In-plane slight wrinkles and sagging are acceptable but acceptable C: In-plane significant wrinkles and sagging are visible and unacceptable

  The obtained evaluation results are shown in Table 4.

<Preparation of polarizing plate>
(Corona treatment of optical film)
The optical film 1-8 produced above was subjected to corona discharge irradiation under the condition of 1500 W · min / m ^{2 on} the surface where the (B) layer and (C) layer of the (A) layer were not formed. The optical films 12, 13, and 15 were similarly subjected to corona treatment.
Moreover, the same corona treatment was given to the upper surface (surface on the opposite side to a support body) of the (A) layer of the optical films 9-11 and 14 produced above.

(Production of polarizer)
A polarizer having a thickness of 3 μm was produced according to Example 1 of Japanese Patent No. 4691205.
A polarizer having a thickness of 20 μm was produced as follows.
After immersing a 75 μm thick polyvinyl alcohol film made of polyvinyl alcohol having an average polymerization degree of about 2400 and a saponification degree of 99.9 mol% or more in pure water at 30 ° C., the mass ratio of iodine / potassium iodide / water is 0. It was immersed in an aqueous solution of 02/2/100 at 30 ° C. Then, it immersed at 56.5 degreeC in the aqueous solution whose mass ratio of potassium iodide / boric acid / water is 12/5/100.
Subsequently, it was washed with pure water at 8 ° C. and then dried at 65 ° C. to obtain a polarizing film (polarizer) in which iodine was adsorbed and oriented on a polyvinyl alcohol film. Stretching was mainly performed in the iodine staining and boric acid treatment steps, and the total stretching ratio was 5.3 times.

(Lamination)
As the polarizing plate protective film A, the corona-treated surface ((A) layer) of the optical films 1 to 8, 12, 13, and 15 after the corona treatment and a polarizer were bonded together with a PVA adhesive.
Moreover, in polarizing plate 1, 2, 4-14, what applied the corona treatment similarly to the optical film 9-11, 14 as a polarizing plate protective film B on the other surface of a polarizer is affixed with a PVA adhesive. Combined. Thereafter, it was heat-dried to prepare each polarizing plate sample.
The protective film A, polarizer, and protective film B used for each polarizing plate sample are shown in Table 5 below.

<Evaluation of wet heat durability>
About each polarizing plate sample produced above, orthogonal transmittance CT in wavelength 410nm was measured using JASCO Corporation automatic polarization film measuring device VAP-7070. In the measurement, measurement was performed at 410 nm, and the average value of 10 measurements was used.
The wet heat durability test was performed as follows in a form in which a polarizing plate was attached to glass via an adhesive. A sample (about 5 cm × 5 cm) in which a polarizing plate was pasted on glass was prepared. At this time, it bonded so that the protective film B or a polarizer might become the glass side. The protective film A side of this sample was set facing the light source, and the orthogonal transmittance of the polarizing plate was measured.
Then, the orthogonal transmittance was measured by the same method after storing for 1000 hours in an environment of 60 ° C. and 90% relative humidity. The change of the orthogonal transmittance before and after aging was determined, and the result was shown in Table 5 as the polarizer durability.
Here, the change amount of the orthogonal transmittance is calculated by the following equation.
Change in orthogonal transmittance (%) = orthogonal transmittance after wet heat durability test (%)-orthogonal transmittance before wet heat durability test (%)
A: Change in orthogonal transmittance is less than 0.06% B: Change in orthogonal transmittance is 0.06% or more and less than 0.08% C: Change in orthogonal transmittance is 0.08% or more, 0 Less than 1% D: Change in orthogonal transmittance is 0.1% or more A to C in the above evaluation are acceptable levels.

Claims (8)

(A) a layer containing a cyclic polyolefin resin;
(B) a layer containing a resin polymerized by light and / or heat having an alicyclic structure in the molecule;
(C) a hard coat layer;
In this order, and the film thickness of the (C) layer is 10 μm or less .   2. The optical film according to claim 1, wherein the film thickness of the (A) layer is 20 μm or less, and the film thickness of the (B) layer is 20 μm or less. A resin polymerized by light and / or heat having an alicyclic structure in the molecule is a light and / or heat compound having a group represented by any one of the following general formulas (I) to (V). the optical film according to claim 1 or 2 which is in polymerized resin.

In general formula (I), L and L ′ each independently represent a divalent or higher linking group. n represents an integer of 1 to 3.

In general formula (II), L and L ′ each independently represent a divalent or higher linking group. n represents an integer of 1 to 2.

In general formula (III), L and L ′ each independently represent a divalent or higher linking group. n represents an integer of 1 to 2.

In general formula (IV), L and L ′ each independently represent a divalent or higher valent linking group, and L ″ represents a hydrogen atom or a divalent or higher valent linking group.

In general formula (V), L and L ′ each independently represent a divalent or higher linking group. The cyclic polyolefin resin as claimed in any one of claims 1 to 3 which is a polymer having a structural unit derived from the cycloolefin represented by the following formula (A-II) or (A-III) Optical film.

In general formulas (A-II) to (A-III), m represents an integer of 0 to 4. R ^{3 to} R ⁶ each independently represent a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, and X ^{2 to} X ³ and Y ^{2 to} Y ³ each independently represent a hydrogen atom or a hydrocarbon having 1 to 10 carbon atoms. group, a halogen atom, a hydrocarbon group having 1 to 10 carbon atoms substituted with a halogen atom, which may have a substituent vinyl group, (meth) acryloyl _{group, - (CH 2) n COOR} 11, - ( ^{_{CH 2) n OCOR 12, -}} (CH 2) n NCO, - (CH 2) n NO 2, - (CH 2) n CN, - (CH 2) n CONR 13 R 14, - (CH 2) n NR ¹³ R ¹⁴ , — (CH ₂ ) _n OZ, — (CH ₂ ) _n W, or (—CO) ₂ O, (—CO) ₂ NR ¹⁵ composed of X ² and Y ² or X ³ and Y ³ Indicates. R ¹¹ , R ¹² , R ¹³ , R ¹⁴ and R ¹⁵ are each independently a hydrogen atom, a hydrocarbon group having 1 to 20 carbon atoms, Z is a hydrocarbon group or a hydrocarbon group substituted with halogen, and W is SiR ¹⁶ _p D _3-p (R ¹⁶ is a hydrocarbon group having 1 to 10 carbon atoms, D is a halogen atom, —OCOR ¹⁶ or —OR ¹⁶ , p is an integer of 0 to 3), n is 0 to 10 Indicates an integer. It is a polarizing plate which has a polarizer and the optical film of any one of Claims 1-4 , Comprising:
A polarizing plate having a polarizer, (A) layer, and (B) layer in this order. The polarizing plate according to claim 5 , wherein the thickness of the polarizer is 10 μm or less, and the thickness of the entire polarizing plate is 40 μm or less. The manufacturing method of the optical film of any one of Claims 1-4 which has the process of following (a)-(f).
(A) The process of apply | coating the 1st solution containing cyclic polyolefin resin and a 1st solvent on a support body, and forming a 1st application layer (b) The 1st contained in the said 1st application layer (C) Step of obtaining a layer by drying the solvent (c) On the layer (A), a second solution containing a polymerizable compound having an alicyclic structure in the molecule and a second solvent is applied. The step of forming the second coating layer (d) The step of drying the second solvent contained in the second coating layer (e) The polymerizable compound having an alicyclic structure in the molecule contained in the second coating layer The step of obtaining a resin having an alicyclic structure in the molecule by polymerization with light and / or heat, and obtaining the layer (B) (f) A laminate comprising the layer (A) and the layer (B), Process of peeling from the support The image display apparatus containing the optical film of any one of Claims 1-4 , or the polarizing plate of Claim 5 or 6 .

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