JP5375043B2 - Method for producing laminated optical film, laminated optical film and use thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a multilayer optical film, wherein a contrast ratio, as a screen is viewed from an oblique direction at a liquid crystal display device is high, a color shift amount when the screen is viewed from the oblique direction is small, uniform screen display is made possible, and further, durability is superior and imprinting of external light is less, and to provide a method for producing the film, and a polarizing plate and the liquid crystal display device that uses the film. <P>SOLUTION: The method for producing the multilayer optical film includes a process of laminating and film-forming a resin of positive intrinsic birefringence and the resin of negative intrinsic birefringence by a co-extrusion method and obtaining a rolled film, wherein a layer constituted of the resin of the positive intrinsic birefringence and a layer constituted of the resin of the negative intrinsic birefringence are laminated, and a process of uniaxially extending the obtained rolled film in a direction orthogonal to the film longitudinal direction. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a method for producing a laminated optical film, a laminated optical film, and uses thereof. Specifically, the present invention relates to a laminated optical film that realizes excellent viewing angle characteristics in a liquid crystal display device, a manufacturing method thereof, a polarizing plate using the film, and a liquid crystal display device.

  The retardation film is generally used for the purpose of compensating the viewing angle of the liquid crystal display device, and functions to prevent light leakage at an oblique viewing angle and to prevent a decrease in contrast ratio. Examples of the optical film used as the retardation film include a polycarbonate film, a polyester film, a cellulose acetate film, and a cyclic olefin film.

Among them, the cyclic olefin film is attracting attention as a material for various optical components including a retardation film because it is excellent in transparency, heat resistance, dimensional stability, low photoelasticity and the like.
In recent years, in addition to the conventional TN mode, a high viewing angle liquid crystal mode such as a VA mode or an IPS mode has been put into practical use, and a liquid crystal display device (a liquid crystal television) has been widely used in television applications that require high image quality. For example, as a retardation film for a VA mode liquid crystal display device, a compensation method combining an A plate and a C plate and a compensation method combining one or two biaxial films are particularly effective in improving the viewing angle. It is known to be expensive.

  However, even with these compensation methods, a color change when the screen is viewed from an oblique direction (hereinafter abbreviated as a color shift), for example, a place where it should be black in a black display state appears colored purple, The viewing angle compensation was insufficient. In order to improve this, there is a need for a retardation film having a so-called reverse wavelength dispersion property that the phase difference is smaller as the wavelength is shorter in the visible light region, and the phase difference is increased as the wavelength is longer. Are known. For example, Patent Document 1 proposes a method for realizing reverse wavelength dispersion by modifying a resin used for a retardation film. However, it has not been widely put into practical use because it becomes difficult to establish resin production conditions due to resin modification, and the strength, transparency, stability, etc. of the film are impaired.

  As a method other than the modification of the resin, there is a method in which a layer having a specific retardation is laminated and the total retardation is controlled so as to have reverse wavelength dispersion. For example, Patent Document 2 proposes a method of realizing reverse wavelength dispersion by laminating a retardation layer made of a polymerizable liquid crystal and a resin film. However, a retardation layer made of a polymerizable liquid crystal has a high difficulty in production because it is necessary to control a layer having a thickness of about several microns with a thickness variation of several percent. In addition, with such a stacking method, a predetermined phase difference value and reverse wavelength dispersion can be obtained when observed from the front direction, but when observed from an oblique direction, the predetermined phase difference is caused by the effect of optical axis deviation. There is a problem that viewing angle compensation in an oblique direction cannot be performed.

As another method for laminating the retardation layer, Patent Document 3 proposes film formation and retardation film production by a coextrusion method. However, the adhesion of each layer is poor, and it is necessary to sandwich an adhesive layer between the layers, resulting in a problem that the layer configuration and the manufacturing apparatus become complicated. As described above, a method for increasing the contrast ratio from the oblique direction and reducing the color shift has not been sufficiently established, and an improvement has been demanded. Furthermore, in addition to the above-mentioned excellent viewing angle characteristics, the liquid crystal display devices for portable devices such as mobile phones and portable game machines are also required to have durability that can withstand long-term use in harsh environments. It was.
JP 2006-225626 A JP 2006-268033 A JP 2004-133313 A

  The present invention has a high contrast ratio when the screen is viewed from an oblique direction in a liquid crystal display device, and a small color shift amount when the screen is viewed from an oblique direction, enabling a more uniform screen display and durability. It is an object of the present invention to provide a laminated optical film having excellent properties and little reflection of external light, a manufacturing method thereof, a polarizing plate and a liquid crystal display device using the same.

The method for producing the laminated optical film of the present invention comprises:
A structural unit (A1) represented by the following formula (A1);
The structural unit (A2) represented by the following formula (A2) and / or the structural unit (A3) represented by the following formula (A3),
Vinyl aromatic resin (A) comprising a copolymer in which the total content of the structural unit (A2) and / or the structural unit (A3) is 5 to 40 mol% of all structural units constituting the copolymer. When,
Co-extruding the cyclic olefin resin (B) to obtain a laminated raw film having a vinyl aromatic resin layer and a cyclic olefin resin layer;
A step of obtaining a laminated optical film by uniaxially stretching the obtained laminated raw film in a direction perpendicular to the longitudinal direction;
A laminated optical film in which the thickness ratio of the cyclic olefin-based resin layer is in the range of 50 to 90% is manufactured.

（式（Ａ１）中、Ａ¹は水素原子またはメチル基を示す。Ａ²〜Ａ⁴は各々独立に水素原子
；ハロゲン原子；酸素、窒素、イオウ若しくはケイ素を含む連結基を有していてもよい置換または非置換の炭素原子数１〜３０の炭化水素基；または極性基を表す。）

(In Formula (A1), A ¹ represents a hydrogen atom or a methyl group. A ^{2 to} A ⁴ may each independently have a hydrogen atom; a halogen atom; a linking group containing oxygen, nitrogen, sulfur or silicon. A good substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms; or a polar group.)

（式（Ａ２）中、Ｘは酸素原子もしくは置換基を有する窒素原子である。式（Ａ３）中、Ａ⁵は水素原子またはメチル基を示す。Ａ⁶は水素原子もしくは炭素原子数１〜３０の炭化
水素基である。）
前記本発明の積層光学フィルムの製造方法では、環状オレフィン系樹脂（Ｂ）が、下記式（Ｂ１）で表わされる構造単位（Ｂ１）と、下記式（Ｂ２）で表わされる構造単位（Ｂ２）とを有することが好ましい。

(In Formula (A2), X is an oxygen atom or a nitrogen atom having a substituent. In Formula (A3), A ⁵ represents a hydrogen atom or a methyl group. A ⁶ represents a hydrogen atom or a carbon atom number of 1 to 30. Hydrocarbon group.)
In the method for producing a laminated optical film of the present invention, the cyclic olefin-based resin (B) includes a structural unit (B1) represented by the following formula (B1) and a structural unit (B2) represented by the following formula (B2). It is preferable to have.

（式（Ｂ１）中、ｍは０以上の整数、ｐは０以上の整数であり、Ｘは独立に式：−ＣＨ＝ＣＨ−で表される基または式：−ＣＨ₂ＣＨ₂−で表される基であり、Ｒ¹〜Ｒ⁴は、それぞれ独立に下記（a）〜（e）で表されるものを表すか、（f）または（g）を表す。
（a）水素原子、
（b）ハロゲン原子、
（c）酸素原子、硫黄原子、窒素原子もしくはケイ素原子を含む連結基を含む置換もしく
は非置換の炭素原子数１〜３０の炭化水素基、
（d）置換もしくは非置換の炭素原子数１〜３０の炭化水素基、
（e）極性基、
（f）Ｒ¹とＲ²、またはＲ³とＲ⁴が、相互に結合して形成されたアルキリデン基を表し、
前記結合に関与しないＲ¹〜Ｒ⁴は相互に独立に前記（a）〜（e）より選ばれるものを表す、
（g）Ｒ¹とＲ²、Ｒ³とＲ⁴、またはＲ²とＲ³が、相互に結合して形成された芳香環あるい
は非芳香環の単環もしくは多環の炭化水素環または複素環を表し、前記結合に関与しないＲ¹〜Ｒ⁴は相互に独立に前記（a）〜（e）より選ばれるものを表す。］

(In formula (B1), m is an integer of 0 or more, p is an integer of 0 or more, and X is independently a group represented by the formula: —CH═CH— or a formula: —CH ₂ CH ₂ —. R ^{1 to} R ⁴ each independently represents one represented by the following (a) to (e), or represents (f) or (g).
(A) a hydrogen atom,
(B) a halogen atom,
(C) a substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms including a linking group containing an oxygen atom, a sulfur atom, a nitrogen atom or a silicon atom,
(D) a substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms,
(E) a polar group,
(F) R ¹ and R ² , or R ³ and R ⁴ represent an alkylidene group formed by bonding to each other;
R ^{1 to} R ^{4 that} are not involved in the bond are independently selected from the above (a) to (e),
(G) R ¹ and R ² , R ³ and R ⁴ , or R ² and R ³ bonded together to form an aromatic ring or a non-aromatic monocyclic or polycyclic hydrocarbon ring or heterocyclic ring And R ^{1 to} R ⁴ not involved in the bond are independently selected from the above (a) to (e). ]

（式（Ｂ２）中、Ｙは独立に式：−ＣＨ＝ＣＨ−で表される基または式：−ＣＨ₂ＣＨ₂−で表される基であり、Ｒ⁵〜Ｒ⁸はそれぞれ独立に下記（a）〜（e）で表されるものを表す
か、（f）または（g）を表す。
（a）水素原子、
（b）ハロゲン原子、
（c）酸素原子、硫黄原子、窒素原子もしくはケイ素原子を含む連結基を含む置換もしく
は非置換の炭素原子数１〜３０の炭化水素基、
（d）置換もしくは非置換の炭素原子数１〜３０の炭化水素基、
（e）極性基、
（f）Ｒ⁵とＲ⁶、またはＲ⁷とＲ⁸が、相互に結合して形成されたアルキリデン基を表し、
前記結合に関与しないＲ⁵〜Ｒ⁸は相互に独立に前記（a）〜（e）より選ばれるものを表す、
（g）Ｒ⁵とＲ⁶、Ｒ⁷とＲ⁸、またはＲ⁶とＲ⁷が、相互に結合して形成された芳香環あるい
は非芳香環の単環もしくは多環の炭化水素環または複素環を表し、前記結合に関与しないＲ⁵〜Ｒ⁸は相互に独立に前記（a）〜（e）より選ばれるものを表す。］

(In formula (B2), Y is independently a group represented by the formula: —CH═CH— or a group represented by the formula: —CH ₂ CH ₂ —, and R ^{5 to} R ⁸ are each independently the following: It represents what is represented by (a) to (e), or represents (f) or (g).
(A) a hydrogen atom,
(B) a halogen atom,
(C) a substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms including a linking group containing an oxygen atom, a sulfur atom, a nitrogen atom or a silicon atom,
(D) a substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms,
(E) a polar group,
(F) R ⁵ and R ⁶ , or R ⁷ and R ⁸ represent an alkylidene group formed by bonding to each other;
R ^{5 to} R ⁸ not involved in the bond each independently represents one selected from (a) to (e),
(G) R ⁵ and R ⁶ , R ⁷ and R ⁸ , or R ⁶ and R ⁷ bonded together to form an aromatic ring or a non-aromatic monocyclic or polycyclic hydrocarbon ring or heterocyclic ring R ^{5 to} R ⁸ not involved in the bond are independently selected from the above (a) to (e). ]

In the method for producing a laminated optical film of the present invention, the laminated optical film preferably satisfies all the characteristics represented by the following formulas (i) to (iv).
R450 <R550 <R650 (i)
1.0 <R650 / R550 <1.2 (ii)
70 nm ≦ R550 ≦ 150 nm (iii)
1.0 ≦ NZ ≦ 3.0 (iv)
(In the above formulas (i) to (iii), R450, R550, and R650 have a wavelength of 450 nm in this order.
It represents the in-plane retardation of the laminated optical film at 550 nm and 650 nm. The above formula (iv
) Is a coefficient represented by NZ = (nx−nz) / (nx−ny), and is a value at a wavelength of 550 nm. Here, nx is the maximum refractive index in the laminated optical film plane, ny is the refractive index in the direction orthogonal to nx in the laminated optical film plane, and nz is the refractive index in the thickness direction of the laminated optical film orthogonal to nx and ny. Represents a rate. )
In the method for producing a laminated optical film of the present invention, the vinyl aromatic resin layer and the cyclic olefin resin layer are preferably in direct contact with each other.

  In the method for producing a laminated optical film of the present invention, the glass transition temperature of the vinyl aromatic resin (A) and the glass transition temperature of the cyclic olefin resin (B) are both 110 ° C. or higher, and both The difference is preferably within 20 ° C.

The laminated optical film of the present invention is obtained by the above-described method for producing a laminated optical film of the present invention.
In the laminated optical film of the present invention, the vinyl aromatic resin layer and the cyclic olefin resin layer are laminated in direct contact with each other and satisfy all the characteristics represented by the following formulas (i) to (iv). It is characterized by.
R450 <R550 <R650 (i)
1.0 <R650 / R550 <1.2 (ii)
70 nm ≦ R550 ≦ 150 nm (iii)
1.0 ≦ NZ ≦ 3.0 (iv)
(In the above formulas (i) to (iii), R450, R550, and R650 have a wavelength of 450 nm in this order.
It represents the in-plane retardation of the laminated optical film at 550 nm and 650 nm. The above formula (iv
) Is a coefficient represented by NZ = (nx−nz) / (nx−ny), and is a value at a wavelength of 550 nm. Here, nx is the maximum refractive index in the laminated optical film plane, ny is the refractive index in the direction orthogonal to nx in the laminated optical film plane, and nz is the refractive index in the thickness direction of the laminated optical film orthogonal to nx and ny. Represents a rate. )
Such a laminated optical film of the present invention is preferably obtained by the method for producing a laminated optical film of the present invention.

The polarizing plate of the present invention is characterized in that the laminated optical film of the present invention is bonded to at least one surface of a polarizer via an adhesive or an adhesive.
Such a polarizing plate of the present invention preferably further has at least one layer selected from an antireflection layer and an antiglare layer.

  The elliptically polarizing plate of the present invention is the polarizing plate of the present invention, and is bonded so that the maximum refractive index direction in the plane of the laminated optical film is not parallel to the transmission axis direction of the polarizer. It is characterized by.

  The liquid crystal display device of the present invention has the polarizing plate or the elliptically polarizing plate of the present invention.

  According to the present invention, in a liquid crystal display device, a liquid crystal display that has a high contrast ratio when the screen is viewed from an oblique direction, a small color shift amount when the screen is viewed from an oblique direction, and a more uniform screen display. A laminated optical film suitable for an apparatus and a method for producing the same can be provided. In addition, by using the laminated optical film of the present invention, the contrast ratio when the screen is viewed from an oblique direction in a liquid crystal display device is high, and the color shift amount when the screen is viewed from an oblique direction is small and more uniform. A liquid crystal display device capable of screen display can be provided.

Hereinafter, the present invention will be specifically described.
[Method for producing laminated optical film]
The method for producing the laminated optical film of the present invention comprises:
Coextruding the vinyl aromatic resin (A) and the cyclic olefin resin (B) to obtain a laminated raw film having a vinyl aromatic resin layer and a cyclic olefin resin layer;
And a step of obtaining a laminated optical film by uniaxially stretching the obtained laminated raw film in a direction perpendicular to the longitudinal direction.

Vinyl aromatic resin (A)
The vinyl aromatic resin (A) used in the present invention is
Having a structural unit (A1) represented by the following formula (A1), and
It has a structural unit (A2) represented by the following formula (A2) and / or a structural unit (A3) represented by the following formula (A3).

（式（Ａ１）中、Ａ¹は水素原子またはメチル基を示す。Ａ²〜Ａ⁴は各々独立に水素原子
；ハロゲン原子；酸素、窒素、イオウ若しくはケイ素を含む連結基を有していてもよい置換または非置換の炭素原子数１〜３０の炭化水素基；または極性基を表す。）

(In Formula (A1), A ¹ represents a hydrogen atom or a methyl group. A ^{2 to} A ⁴ may each independently have a hydrogen atom; a halogen atom; a linking group containing oxygen, nitrogen, sulfur or silicon. A good substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms; or a polar group.)

（式（Ａ２）中、Ｘは酸素原子もしくは置換基を有する窒素原子である。式（Ａ３）中、Ａ⁵は水素原子またはメチル基を示す。Ａ⁶は水素原子もしくは炭素原子数１〜３０の炭化水素基である。）
構造単位（Ａ１）を誘導する単量体の具体例としては、スチレン、α−メチルスチレン、ｐ−メチルスチレン、ｏ−メチルスチレン、ｐ−トリフルオロメチルスチレン、ｐ−メトキシスチレン、ｐ−ヒドロキシスチレン、ｐ−クロロスチレン、ｐ−ニトロスチレン、ｐ−アミノスチレン、ｐ−カルボキシスチレン、ｐ−フェニルスチレン、ｐ−ｔｅｒｔブトキシスチレン、２，４，６−トリメチルスチレンなどが挙げられる。これら単量体はいずれか単独で用いてもよく、２種類以上を併用してもよい。これらの単量体のうち、スチレン、α−メチルスチレン、ｐ−ヒドロキシスチレンを単独で／併用して用いるのが好ましい。

(In Formula (A2), X is an oxygen atom or a nitrogen atom having a substituent. In Formula (A3), A ⁵ represents a hydrogen atom or a methyl group. A ⁶ represents a hydrogen atom or a carbon atom number of 1 to 30. Hydrocarbon group.)
Specific examples of the monomer for deriving the structural unit (A1) include styrene, α-methylstyrene, p-methylstyrene, o-methylstyrene, p-trifluoromethylstyrene, p-methoxystyrene, and p-hydroxystyrene. , P-chlorostyrene, p-nitrostyrene, p-aminostyrene, p-carboxystyrene, p-phenylstyrene, p-tertbutoxystyrene, 2,4,6-trimethylstyrene, and the like. Any of these monomers may be used alone, or two or more of these monomers may be used in combination. Of these monomers, styrene, α-methylstyrene, and p-hydroxystyrene are preferably used alone / in combination.

  Specific examples of the monomer for deriving the structural unit (A2) include N-substituted maleimides such as maleic anhydride, maleimide and N-phenylmaleimide, maleic acid and derivatives thereof, fumaric acid and derivatives thereof, and the like. Any of these monomers may be used alone, or two or more of these monomers may be used in combination. Of these monomers, maleic anhydride and N-phenylmaleimide are preferably used in terms of heat resistance and adhesion to the cyclic olefin resin layer.

  Specific examples of the monomer for deriving the structural unit (A3) include (meth) acrylic acid, (meth) acrylic acid alkyl esters such as methyl (meth) acrylate, and (meth) acrylic amide. Any of these monomers may be used alone, or two or more of these monomers may be used in combination. Of these monomers, (meth) acrylic acid and methyl (meth) acrylate are preferably used in terms of heat resistance and adhesion to the cyclic olefin-based resin layer.

  The vinyl aromatic resin (B) used in the present invention may have both the structural unit (A2) and the structural unit (A3), and either the structural unit (A2) or the structural unit (A3). You may have only. Moreover, the acid anhydride structure or imide structure of the structural unit (A2) may be hydrolyzed to a dicarboxylic acid structure or an amic acid structure.

In the present invention, in the vinyl aromatic resin (A), in addition to the structural units (A1), (A2) and (A3) described above, structural units derived from other copolymerization components as necessary. May be included. Examples of other copolymer components include ethylene, propylene, butene, butadiene, isoprene, (meth) acrylonitrile, α-chloroacrylonitrile, vinyl acetate, vinyl chloride, and the like. The structural unit derived from the other copolymerization component is 10 mol% or less, preferably 5 mol% or less in all the structural units constituting the vinyl aromatic resin (A).

The vinyl aromatic resin (A) used in the present invention comprises the above structural units (A2) and / or (A3) in a total of 5 to 5 in all the structural units constituting the vinyl aromatic resin (A). 40m
ol%, preferably 10 to 35 mol%. Moreover, the preferable content rate of the structural unit (A1) in vinyl aromatic resin (A) is 60-95 mol%, More preferably, it is 65-90 mol%.

The vinyl aromatic resin (A) used in the present invention has a logarithmic viscosity (η) measured in a chlorobenzene solution (concentration 0.5 g / dL) at 30 ° C. of 0.1 to 3.0 dL / g. It is preferable. Further, the polystyrene-equivalent weight average molecular weight Mw measured by gel permeation chromatography (GPC) is usually 30,000 to 1,000,000, preferably 40,000 to 800,000, more preferably 50,000 to 500,000. If the molecular weight is too small, the strength of a molded product such as a film obtained may be lowered. If the molecular weight is too large, the solution viscosity becomes too high, and the productivity and workability of the resin composition used in the present invention may deteriorate.

Furthermore, the molecular weight distribution (Mw / Mn) of the vinyl aromatic resin (A) is usually 1.0 to 10, preferably 1.2 to 5.0, more preferably 1.2 to 4.0.
The vinyl aromatic resin used in the present invention is produced by a method in which the above-described monomer that induces the repeating units (6), (7), and (8) is polymerized in the presence of a suitable polymerization initiator. Is preferred. As the polymerization initiator, it is preferable to use a radical polymerization initiator, an anionic polymerization catalyst, a coordination polymerization catalyst, a cationic polymerization catalyst or the like, and it is particularly preferable to use a radical polymerization initiator.

  As the radical initiator used in the polymerization reaction, a known organic peroxide that generates free radicals or an azobis-based radical polymerization initiator can be used. Note that a polyfunctional initiator or an initiator that easily causes a hydrogen abstraction reaction is not preferable because the linearity of the resulting styrene copolymer may be lowered.

  In the vinyl aromatic resin (A) used in the present invention, the above monomer that induces the structural unit (A1) and (A2) and / or (A3) is added in the presence of a suitable polymerization initiator. It is preferably produced by a polymerization reaction method. As the polymerization initiator, it is preferable to use a radical polymerization initiator, an anionic polymerization catalyst, a coordination polymerization catalyst, a cationic polymerization catalyst or the like, and it is particularly preferable to use a radical polymerization initiator.

  As the radical initiator used in the polymerization reaction, a known organic peroxide that generates free radicals or an azobis-based radical polymerization initiator can be used. Note that a polyfunctional initiator or an initiator that easily causes a hydrogen abstraction reaction is not preferable because the linearity of the resulting styrene copolymer may be lowered.

Organic peroxides include diacetyl peroxide, dibenzoyl peroxide, diisobutyroyl peroxide, di (2,4-dichlorobenzoyl) peroxide, di (3,5,5-trimethylhexanoyl) peroxide, di Diacyl peroxides such as octanoyl peroxide, dilauroyl peroxide, distearoyl peroxide, bis {4- (m-toluoyl) benzoyl} peroxide;
Ketone peroxides such as methyl ethyl ketone peroxide, cyclohexanone peroxide, methylcyclohexanone peroxide, acetylacetone peroxide;
Hydrogen peroxide, t-butyl hydroperoxide, α-cumene hydroperoxide, p-menthane hydroperoxide, diisopropylbenzene hydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide, t-hexyl hydro Hydroperoxides such as peroxides;
Di-t-butyl peroxide, dicumyl peroxide, dilauryl peroxide,
α, α′-bis (t-butylperoxy) diisopropylbenzene, 2,5-dimethyl-2,5-bis (t-butylperoxy) hexane, t-butylcumyl peroxide, 2,5-dimethyl-2 Dialkyl peroxides such as, 5-bis (t-butylperoxy) hexyne-3;
t-butyl peroxyacetate, t-butyl peroxypivalate, t-hexyl peroxypivalate, 1,1,3,3-tetramethylbutylperoxy 2-ethylhexanoate, 2,5-dimethyl-2 , 5-bis (2-ethylhexanoylperoxy) hexane, 1-cyclohexyl-1-methylethylperoxy 2-ethylhexanoate, t-hexylperoxy 2-ethylhexanoate, t-butylperoxy 2 -Ethyl hexanoate, t-butyl peroxyisobutyrate, t-butyl peroxy maleate, t-butyl peroxy 3,5,5-trimethyl hexanoate, t-butyl peroxy laurate, 2,5 -Dimethyl-2,5-bis (m-toluoylperoxy) hexane, α, α'-bis (neodecanoylpa Oxy) diisopropylbenzene, cumylperoxyneodecanoate, 1,1,3,3-tetramethylbutylperoxyneodecanoate, 1-cyclohexyl-1-methylethylperoxyneodecanoate, t-hexylper Oxyneodecanoate, t-butylperoxyneodecanoate, t-butylperoxybenzoate, t-hexylperoxybenzoate, bis (t-butylperoxy) isophthalate, 2,5-dimethyl-2,5 -Peroxyesters such as bis (benzoylperoxy) hexane, t-butylperoxy m-toluoylbenzoate, 3,3 ', 4,4'-tetra (t-butylperoxycarbonyl) benzophenone;
1,1-bis (t-hexylperoxy) 3,3,5-trimethylcyclohexane, 1,1-bis (t-hexylperoxy) cyclohexane, 1,1-bis (t-butylperoxy) 3,3 , 5-trimethylcyclohexane, 1,1-bis (t-butylperoxy) cyclohexane, 1,1-bis (t-butylperoxy) cyclododecane, 2,2-bis (t-butylperoxy) butane, n -Peroxyketals such as butyl 4,4-bis (t-butylperoxy) pivalate, 2,2-bis (4,4-di-t-butylperoxycyclohexyl) propane;
Peroxymonocarbonates such as t-hexylperoxyisopropyl monocarbonate, t-butylperoxyisopropyl monocarbonate, t-butylperoxy 2-ethylhexyl monocarbonate, t-butylperoxyallyl monocarbonate;
Di-sec-butyl peroxydicarbonate, di-n-propyl peroxydicarbonate, diisopropyl peroxydicarbonate, bis (4-t-butylcyclohexyl) peroxydicarbonate, di-2-ethoxyethyl peroxydicarbonate Peroxydicarbonates such as di-2-ethylhexyl peroxydicarbonate, di-2-methoxybutyl peroxydicarbonate, di (3-methyl-3-methoxybutyl) peroxydicarbonate;
In addition, although t-butyl trimethylsilyl peroxide etc. are mentioned, the organic peroxide used for this invention is not limited to these exemplary compounds.

As the azobis radical polymerization initiator, azobisisobutyronitrile, azobisisovaleronitrile, 2,2′-azobis (4-methoxy-2,4-dimethylvaleronitrile), 2,2′-azobis (2 , 4-dimethylvaleronitrile), 2,2′-azobis (2-methylbutyronitrile), 1,1′-azobis (cyclohexane-1-carbonitrile)
2- (carbamoylazo) isobutyronitrile, 2,2′-azobis [2-methyl-N
-{1,1-bis (hydroxymethyl) -2-hydroxyethyl} propionamide], 2,2'-azobis [2-methyl-N- {2- (1-hydroxybutyl)} propionamide], 2, 2'-azobis [2-methyl-N- (2-hydroxyethyl) -propionamide], 2,2'-azobis [N- (2-propenyl) -2-methylpropionamide], 2,2'-azobis (N-butyl-2-methylpropionamide), 2,2′-azobis (N-cyclohexyl-2-methylpropionamide), 2,2′-azobis [2- (
5-methyl-2-imidazolin-2-yl) propane] dihydrochloride, 2,2 ′
Azobis [2- (2-imidazolin-2-yl) propane] dihydrochloride, 2,2′-azobis [2- (2-imidazolin-2-yl) propane] disulfate dihydrate, 2,2′- Azobis [2- (3,4,5,6-tetrahydropyrimidine-
2-yl) propane] dihydrochloride, 2,2′-azobis [2- {1- (2-hydroxyethyl) -2-imidazolin-2-yl} propane] dihydrochloride, 2,2′-azobis [ 2- (2-imidazolin-2-yl) propane], 2,2′-azobis (2-methylpropionamidine) dihydrochloride, 2,2′-azobis [N- (
2-carboxyethyl) -2-methyl-propionamidine], 2,2′-azobis (2
-Methylpropionamidoxime), dimethyl 2,2'-azobisbutyrate, 4,4'-azobis (4-cyanopentanoic acid), 2,2'-azobis (2,4,4-trimethylpentane), etc. However, the azobis radical polymerization initiator used in the present invention is not limited to these exemplified compounds.

  These radical initiators are used in an amount of generally 0.01 to 5 mol%, preferably 0.03 to 3 mol%, more preferably 0.05 to 2 mol, based on 100 mol% of the total amount of monomers for inducing the vinyl aromatic resin. %.

  Furthermore, a catalyst may be used for the polymerization reaction of the monomer for inducing the vinyl aromatic resin (A). This catalyst is not particularly limited, and examples thereof include known anionic polymerization catalysts, coordination polymerization catalysts, and cationic polymerization catalysts.

  The polymerization reaction of the monomer for inducing the vinyl aromatic resin (A) is carried out in the presence of the polymerization initiator or catalyst in the bulk polymerization method, solution polymerization method, precipitation polymerization method, emulsion polymerization method, suspension weight It is carried out by copolymerization by a conventionally known method such as a combination method or a bulk-suspension polymerization method.

  The solvent used when performing the solution polymerization is not particularly limited as long as it dissolves the monomer and the polymer, but a hydrocarbon solvent such as cyclohexane, an aromatic hydrocarbon solvent such as toluene, Ketone solvents such as methyl ethyl ketone are preferred. The amount of the solvent used is preferably 0 to 3 times (weight ratio) with respect to the total amount of the monomers.

  The polymerization reaction time is usually 1 to 30 hours, preferably 3 to 20 hours, and the polymerization reaction temperature is not particularly limited because it depends on the type of radical initiator used, but usually 40 to 180 ° C., preferably 50-120 ° C.

  The glass transition temperature of the vinyl aromatic resin (A) is 110 to 200 ° C., more preferably 120 to 170 ° C., in order to ensure thermal stability and coextrusion moldability. The vinyl aromatic resin film used in the present invention may be formed from a resin composition containing the vinyl aromatic resin as described above. In addition to vinyl aromatic resins, resin compositions include antioxidants, heat stabilizers, light stabilizers, phase difference regulators, UV absorbers, antistatic agents, dispersants, and processability as needed. Agent, chlorine scavenger, flame retardant, crystallization nucleating agent, antiblocking agent, antifogging agent, mold release agent, pigment, organic or inorganic filler, neutralizing agent, lubricant, decomposition agent, metal deactivator, Known additives such as antifouling materials, antibacterial agents, other resins, and thermoplastic elastomers can be added as long as the effects of the invention are not impaired.

  Further, commercially available resins such as NOVA Chemicals 'Dilark D332, Dairaku D232, Dainippon Ink & Chemicals' Rurex A14, Rurex A15, CHI MEI PN-177 are also preferably used as the vinyl aromatic resin (A) of the present invention. be able to.

Cyclic olefin resin (B)
The cyclic olefin resin (B) used in the present invention is a polymer obtained by polymerizing or copolymerizing a cyclic olefin monomer having a norbornene skeleton, and examples thereof include the following.
(1) A ring-opening polymer of a cyclic olefin monomer.
(2) A ring-opening copolymer of a cyclic olefin monomer and a copolymerizable monomer.
(3) A hydrogenated (co) polymer of the ring-opening (co) polymer of (1) or (2) above.
(4) A (co) polymer obtained by cyclizing the ring-opening (co) polymer of (1) or (2) by Friedel-Craft reaction and then hydrogenating it.
(5) A saturated copolymer of a cyclic olefin monomer and an unsaturated double bond-containing compound.
(6) Addition (co) polymers of cyclic olefin monomers and hydrogenated (co) polymers thereof.
(7) An alternating copolymer of a cyclic olefin monomer and an acrylate.

Of these, as the cyclic olefin-based resin (B) according to the present invention, the above (1), (2) and (3) are preferable, and the above (3) is more preferable.
More preferably, the cyclic olefin resin (B) used in the present invention has a structural unit (B1) represented by the following formula (B1) and a structural unit (B2) represented by the following formula (B2). Furthermore, it is optional to include structural units other than (B1) and (B2) as necessary.

（式（Ｂ１）中、ｍは０以上の整数、ｐは０以上の整数であり、Ｘは独立に式：−ＣＨ＝ＣＨ−で表される基または式：−ＣＨ₂ＣＨ₂−で表される基であり、Ｒ¹〜Ｒ⁴は、それぞれ独立に下記（a）〜（e）で表されるものを表すか、（f）または（g）を表す。
（a）水素原子、
（b）ハロゲン原子、
（c）酸素原子、硫黄原子、窒素原子もしくはケイ素原子を含む連結基を含む置換もしく
は非置換の炭素原子数１〜３０の炭化水素基、
（d）置換もしくは非置換の炭素原子数１〜３０の炭化水素基、
（e）極性基、
（f）Ｒ¹とＲ²、またはＲ³とＲ⁴が、相互に結合して形成されたアルキリデン基を表し、
前記結合に関与しないＲ¹〜Ｒ⁴は相互に独立に前記（a）〜（e）より選ばれるものを表す、
（g）Ｒ¹とＲ²、Ｒ³とＲ⁴、またはＲ²とＲ³が、相互に結合して形成された芳香環あるい
は非芳香環の単環もしくは多環の炭化水素環または複素環を表し、前記結合に関与しない
Ｒ¹〜Ｒ⁴は相互に独立に前記（a）〜（e）より選ばれるものを表す。］

(In formula (B1), m is an integer of 0 or more, p is an integer of 0 or more, and X is independently a group represented by the formula: —CH═CH— or a formula: —CH ₂ CH ₂ —. R ^{1 to} R ⁴ each independently represents one represented by the following (a) to (e), or represents (f) or (g).
(A) a hydrogen atom,
(B) a halogen atom,
(C) a substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms including a linking group containing an oxygen atom, a sulfur atom, a nitrogen atom or a silicon atom,
(D) a substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms,
(E) a polar group,
(F) R ¹ and R ² , or R ³ and R ⁴ represent an alkylidene group formed by bonding to each other;
R ^{1 to} R ^{4 that} are not involved in the bond are independently selected from the above (a) to (e),
(G) R ¹ and R ² , R ³ and R ⁴ , or R ² and R ³ bonded together to form an aromatic ring or a non-aromatic monocyclic or polycyclic hydrocarbon ring or heterocyclic ring And R ^{1 to} R ⁴ not involved in the bond are independently selected from the above (a) to (e). ]

（式（Ｂ２）中、Ｙは独立に式：−ＣＨ＝ＣＨ−で表される基または式：−ＣＨ₂ＣＨ₂−で表される基であり、Ｒ⁵〜Ｒ⁸はそれぞれ独立に下記（a）〜（e）で表されるものを表すか、（f）または（g）を表す。
（a）水素原子、
（b）ハロゲン原子、
（c）酸素原子、硫黄原子、窒素原子もしくはケイ素原子を含む連結基を含む置換もしく
は非置換の炭素原子数１〜３０の炭化水素基、
（d）置換もしくは非置換の炭素原子数１〜３０の炭化水素基、
（e）極性基、
（f）Ｒ⁵とＲ⁶、またはＲ⁷とＲ⁸が、相互に結合して形成されたアルキリデン基を表し、
前記結合に関与しないＲ⁵〜Ｒ⁸は相互に独立に前記（a）〜（e）より選ばれるものを表す、
（g）Ｒ⁵とＲ⁶、Ｒ⁷とＲ⁸、またはＲ⁶とＲ⁷が、相互に結合して形成された芳香環あるい
は非芳香環の単環もしくは多環の炭化水素環または複素環を表し、前記結合に関与しないＲ⁵〜Ｒ⁸は相互に独立に前記（a）〜（e）より選ばれるものを表す。］
構造単位（Ｂ１）および（Ｂ２）を有する環状オレフィン系樹脂（Ｂ）は、たとえば、下記式（Ｂ１−ｍ）で表わされる１種以上の単量体と、下記式（Ｂ２−ｍ）で表わされる１種以上の単量体とを共重合して、必要に応じて水素添加して得られる。

(In formula (B2), Y is independently a group represented by the formula: —CH═CH— or a group represented by the formula: —CH ₂ CH ₂ —, and R ^{5 to} R ⁸ are each independently the following: It represents what is represented by (a) to (e), or represents (f) or (g).
(A) a hydrogen atom,
(B) a halogen atom,
(C) a substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms including a linking group containing an oxygen atom, a sulfur atom, a nitrogen atom or a silicon atom,
(D) a substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms,
(E) a polar group,
(F) R ⁵ and R ⁶ , or R ⁷ and R ⁸ represent an alkylidene group formed by bonding to each other;
R ^{5 to} R ⁸ not involved in the bond each independently represents one selected from (a) to (e),
(G) R ⁵ and R ⁶ , R ⁷ and R ⁸ , or R ⁶ and R ⁷ bonded together to form an aromatic ring or a non-aromatic monocyclic or polycyclic hydrocarbon ring or heterocyclic ring R ^{5 to} R ⁸ not involved in the bond are independently selected from the above (a) to (e). ]
The cyclic olefin resin (B) having the structural units (B1) and (B2) is represented by, for example, one or more monomers represented by the following formula (B1-m) and the following formula (B2-m). It is obtained by copolymerizing with one or more monomers and hydrogenating as necessary.

（式（Ｂ１−ｍ）中、ｍ、ｐ、Ｒ¹、Ｒ²、Ｒ³およびＲ⁴の定義は、式（Ｂ１）の定義のとおりである。）

(In formula (B1-m), the definitions of m, p, R ¹ , R ² , R ³ and R ⁴ are as defined in formula (B1).)

（式（Ｂ２−ｍ）中、Ｒ⁵、Ｒ⁶、Ｒ⁷およびＲ⁸の定義は、式（Ｂ２）の定義のとおりである。）
式（Ｂ１）、（Ｂ２）、（Ｂ１−ｍ）、（Ｂ２−ｍ）において、Ｒ¹〜Ｒ⁸は、水素原子；ハロゲン原子；酸素、窒素、イオウまたはケイ素を含む連結基を有していてもよい置換または非置換の炭素原子数１〜３０の炭化水素基；または極性基を表す。前記の原子および基について以下に説明する。

(In formula (B2-m), definitions of R ⁵ , R ⁶ , R ⁷ and R ⁸ are as defined in formula (B2).)
In the formulas (B1), (B2), (B1-m), and (B2-m), R ^{1 to} R ⁸ have a hydrogen atom; a halogen atom; a linking group containing oxygen, nitrogen, sulfur, or silicon. A substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms; or a polar group. The above atoms and groups will be described below.

Examples of the halogen atom include a fluorine atom, a chlorine atom, and a bromine atom.
Examples of the hydrocarbon group having 1 to 30 carbon atoms include alkyl groups such as methyl group, ethyl group and propyl group; cycloalkyl groups such as cyclopentyl group and cyclohexyl group; alkenyl groups such as vinyl group, allyl group and propenyl group. Group and the like.

The substituted or unsubstituted hydrocarbon group may be directly bonded to the ring structure or may be bonded via a linking group. Examples of the linking group include a divalent hydrocarbon group having 1 to 10 carbon atoms (for example, an alkylene group represented by — (CH ₂ ) _m — (wherein m is an integer of 1 to 10)); oxygen , A linking group containing nitrogen, sulfur or silicon (for example, a carbonyl group (—CO—), an oxycarbonyl group (—O (CO) —), a sulfone group (—SO ₂ —), an ether bond (—O—), Thioether bond (-S-), imino group (-
NH—), amide bonds (—NHCO—, —CONH—), siloxane bonds (—OSi (R ₂ ) — (wherein R is an alkyl group such as methyl or ethyl)) and the like. The linking group may be included.

  Examples of the polar group include a hydroxyl group, an alkoxy group having 1 to 10 carbon atoms, an alkoxycarbonyl group, an aryloxycarbonyl group, a cyano group, an amide group, an imide ring-containing group, a triorganosiloxy group, a triorganosilyl group, and an amino group. , An acyl group, an alkoxysilyl group, a sulfonyl-containing group, a carboxyl group, and the like. More specifically, examples of the alkoxy group include a methoxy group and an ethoxy group; examples of the alkoxycarbonyl group include a methoxycarbonyl group and an ethoxycarbonyl group; examples of the aryloxycarbonyl group include Examples include phenoxycarbonyl group, naphthyloxycarbonyl group, fluorenyloxycarbonyl group, biphenylyloxycarbonyl group and the like; examples of triorganosiloxy group include trimethylsiloxy group and triethylsiloxy group; Includes a trimethylsilyl group, a triethylsilyl group and the like; examples of the amino group include a primary amino group, and examples of the alkoxysilyl group include a trimethoxysilyl group and a triethoxysilyl group.

More specific examples of the cyclic olefin-based resin in the present invention include copolymers shown in the following <1> to <3>. Of these, the copolymer shown in <3> is particularly preferred because of excellent thermal stability and excellent optical properties.
<1> A ring-opening copolymer of the monomer (B1-m) and the monomer (B2-m).
<2> A ring-opening copolymer of the monomer (B1-m), the monomer (B2-m), and other copolymerizable monomers.
<3> A hydrogenated product of the ring-opening copolymer of <1> and <2>.

<Monomer (B1-m)>
The structural unit (B1) is usually derived from the monomer (B1-m). Specific examples of the monomer (B1-m) are shown below, but the present invention is not limited to these specific examples. Moreover, you may use a monomer (B1-m) combining 2 or more types.

Tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
Pentacyclo [6.5.1.1 ^3,6 . 0 ^2,7 . 0 ^9,13 ] -4-pentadecene,
Pentacyclo [7.4.0.1 ^2,5 . 1 ^9,12 . 0 ^8,13 ] -3-pentadecene,
Tricyclo [4.4.0.1 ^2,5 ] -3-undecene,
8-methoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8-ethoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8-n-propoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8-isopropoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8-n-butoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8-phenoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8-methyl-8-methoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] −
3-dodecene,
8-methyl-8-ethoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] −
3-dodecene,
8-methyl-8-n-propoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8-methyl-8-isopropoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8-methyl-8-n-butoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10
] -3-dodecene,
8-methyl-8-phenoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ]
-3-dodecene,
Pentacyclo [8.4.0.1 ^2,5 . 1 ^9,12 . 0 ^8,13 ] -3-hexadecene,
Heptacyclo [8.7.0.1 ^3,6 . 1 ^10,17 . 1 ^12,15 . 0 ^2,7 . 0 ^11,16 ] -4-Eicosen,
Heptacyclo [8.8.0.1 ^4,7 . 1 ^11,18 . 1 ^13,16 . 0 ^3,8 . 0 ^12,17 ] -5- ^Haneikosen ,
8-ethylidenetetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8-phenyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8-methyl-8-phenyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8-fluorotetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8-fluoromethyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8-difluoromethyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8-trifluoromethyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8-pentafluoroethyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8,8-difluorotetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8,9-difluorotetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8,8-bis (trifluoromethyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] −
3-dodecene,
8,9-bis (trifluoromethyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] −
3-dodecene,
8-methyl-8-trifluoromethyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] −
3-dodecene,

8,8,9-trifluorotetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8,8,9-tris (trifluoromethyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8,8,9,9-tetrafluorotetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-
Dodecene,
8,8,9,9-tetrakis (trifluoromethyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8,8-difluoro-9,9-bis (trifluoromethyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8,9-difluoro-8,9-bis (trifluoromethyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8,8,9-trifluoro-9-trifluoromethyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8,8,9-trifluoro-9-trifluoromethoxytetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8,8,9-trifluoro-9-pentafluoropropoxytetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8-fluoro-8-pentafluoroethyl-9,9-bis (trifluoromethyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8,9-difluoro-8-heptafluoroiso-propyl-9-trifluoromethyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8-chloro-8,9,9-trifluorotetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ]
-3-dodecene,
8,9-dichloro-8,9-bis (trifluoromethyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8- (2,2,2-trifluoroethoxycarbonyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8-methyl-8- (2,2,2-trifluoroethoxycarbonyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene.

Among these, it is preferable to use a monomer having at least one polar group in the molecule as the monomer (B1-m). That is, in the above formula (B1-m), R ¹ and R ³ are a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, R ² and R ⁴ are a hydrogen atom or a monovalent organic group, , R ² and R ⁴ are preferably a polar group other than a hydrogen atom and a hydrocarbon group, because adhesion and adhesion to other materials are improved.

The content of polar groups in the copolymer is determined by the desired function and the like and is not particularly limited. However, in order to improve the adhesion and adhesion to other materials, all structural units (B1) The structural unit (B1) having a polar group therein is usually contained in an amount of 50 mol% or more, preferably 70 mol% or more, more preferably 80 mol% or more. All the structural units (B1) may have a polar group. The presence of the polar group can improve the adhesion with the vinyl aromatic resin layer in the coextrusion film formation.

Furthermore, when the monomer (B1-m) is at least one of R ² and R ^{4 in} the formula (B1-m),
- (CH _{2) n} COOR ⁹
(Here, n is usually an integer of 0 to 5, preferably an integer of 0 to 2, more preferably 0. R ⁹ is a monovalent organic group.)
Is preferable in that the glass transition temperature and water absorption of the resulting copolymer can be easily controlled. Examples of the monovalent organic group represented by R ⁹ include alkyl groups such as a methyl group, an ethyl group and a propyl group; aryl groups such as a phenyl group, a naphthyl group, an anthracenyl group and a biphenylyl group; Examples thereof include monovalent groups having aromatic rings such as fluorenes such as sulfone and tetrahydrofluorene, and heterocyclic rings such as furan rings and imide rings.

Further, in the formula — (CH ₂ ) _n COOR ⁹ , n is usually an integer of 0 to 5 as described above, but the smaller the value of n, the higher the glass transition temperature of the resulting copolymer, which is preferable. In particular, the monomer (B1-m) in which n is 0 is preferable in that its synthesis is easy.

Further, in the above formula (B1-m), the alkyl group is further bonded to the carbon atom to which the polar group represented by the formula — (CH ₂ ) _n COOR ⁹ is bonded. It is preferable in order to balance the property and water absorption. The alkyl group preferably has 1 to 5 carbon atoms, more preferably 1 to 2, and particularly preferably 1.

In addition, it is preferable to use a monomer in which m is 1 and p is 0 in the formula (B1-m) in that a copolymer having a high glass transition temperature can be obtained.
Specific examples of the monomer (B1-m) include 8-methyl-8-methoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene increases the glass transition temperature of the obtained copolymer, hardly receives any adverse effects such as deformation due to water absorption, and has good water adhesion to other materials. It is preferable because the property can be maintained.

<Monomer (B2-m)>
The structural unit (B2) is usually derived from the monomer (B2-m). Specific examples of the monomer (B2-m) are shown below, but the present invention is not limited to these specific examples. Moreover, you may use a monomer (B2-m) combining 2 or more types.

Bicyclo [2.2.1] hept-2-ene (norbornene),
5-methylbicyclo [2.2.1] hept-2-ene,
5-ethylbicyclo [2.2.1] hept-2-ene,
5-methoxycarbonylbicyclo [2.2.1] hept-2-ene,
5-methyl-5-methoxycarbonylbicyclo [2.2.1] hept-2-ene,
5-phenoxycarbonylbicyclo [2.2.1] hept-2-ene,
5-methyl-5-phenoxycarbonylbicyclo [2.2.1] hept-2-ene,
5-cyanobicyclo [2.2.1] hept-2-ene,
5-ethylidenebicyclo [2.2.1] hept-2-ene,
5-phenylbicyclo [2.2.1] hept-2-ene,
5- (2-naphthyl) bicyclo [2.2.1] hept-2-ene (both α and β types are acceptable),
5-fluorobicyclo [2.2.1] hept-2-ene,
5-fluoromethylbicyclo [2.2.1] hept-2-ene,
5-trifluoromethylbicyclo [2.2.1] hept-2-ene,
5-pentafluoroethylbicyclo [2.2.1] hept-2-ene,
5,5-difluorobicyclo [2.2.1] hept-2-ene,
5,6-difluorobicyclo [2.2.1] hept-2-ene,
5,5-bis (trifluoromethyl) bicyclo [2.2.1] hept-2-ene,
5,6-bis (trifluoromethyl) bicyclo [2.2.1] hept-2-ene,
5-methyl-5-trifluoromethylbicyclo [2.2.1] hept-2-ene,
5,5,6-trifluorobicyclo [2.2.1] hept-2-ene,
5,5,6-tris (fluoromethyl) bicyclo [2.2.1] hept-2-ene,
5,5,6,6-tetrafluorobicyclo [2.2.1] hept-2-ene,
5,5,6,6-tetrakis (trifluoromethyl) bicyclo [2.2.1] hept-2-ene,
5,5-difluoro-6,6-bis (trifluoromethyl) bicyclo [2.2.1] hept-2-ene,
5,6-difluoro-5,6-bis (trifluoromethyl) bicyclo [2.2.1] hept-2-ene,
5,5,6-trifluoro-5-trifluoromethylbicyclo [2.2.1] hept-2-ene,
5-fluoro-5-pentafluoroethyl-6,6-bis (trifluoromethyl) bicyclo [2.2.1] hept-2-ene,
5,6-difluoro-5-heptafluoro-iso-propyl-6-trifluoromethylbicyclo [2.2.1] hept-2-ene,
5-chloro-5,6,6-trifluorobicyclo [2.2.1] hept-2-ene,
5,6-dichloro-5,6-bis (trifluoromethyl) bicyclo [2.2.1] hept-2-ene,
5,5,6-trifluoro-6-trifluoromethoxybicyclo [2.2.1] hept-2-ene,
5,5,6-trifluoro-6-heptafluoropropoxybicyclo [2.2.1] hept-2-ene,
5- (4-phenylphenyl) bicyclo [2.2.1] hept-2-ene 4- (bicyclo [2.2.1] hept-5-en-2-yl) phenylsulfonylbenzene,
Tricyclo [5.2.1.0 ^2,6 ] -8-decene,
Tricyclo [4.3.0.1 ^2,5 ] deca-3,7-diene (dicyclopentadiene)
And so on.

Among these, R ^{5 to} R ⁸ in the formula (B2-m) are all hydrogen atoms, or any one of them is a hydrocarbon group having 1 to 30 carbon atoms and the other is a hydrogen atom (B2- m) is preferable in that the effect of improving the toughness of the obtained optical film is large. In particular, R ^{5 to} R ⁸ are all hydrogen atoms, or any one of them is a methyl group, an ethyl group, or a phenyl group. Monomers that are all hydrogen atoms are preferred from the viewpoint of heat resistance. Furthermore, bicyclo [2.2.1] hept-2-ene (norbornene), 5-phenylbicyclo [2.2.1] hept-2-ene, tricyclo [4.3.0.1 ^2,5 ] deca -3,7-diene (dicyclopentadiene)
Is preferable in that it can be easily synthesized and can improve the toughness of the resin, adjust the glass transition temperature, and ensure good coextrusion moldability.

In the present invention, the use ratio of the monomer (B1-m) to the monomer (B2-m) is usually in the weight ratio of monomer (B1-m): monomer (B2-m) = 95: 5 to 5:95, preferably 9
5: 5 to 60:40, more preferably 95: 5 to 70:30, and still more preferably 95: 5 to 75:25. If the proportion of the monomer (B1-m) is larger than the above range, the effect of improving toughness may not be expected. Conversely, if the proportion of the monomer (B1-m) is smaller than the above range, the glass transition temperature is low. It may become low and a problem may arise in heat resistance.

  Moreover, in order to improve adhesiveness and adhesiveness with other materials, the repeating unit having a polar group in the total amount of the structural unit (B1) and the structural unit (B2) is usually 50 to 95 mol%, preferably 70 to 95. It is contained in an amount of mol%, more preferably 80 to 95 mol%. The presence of the polar group can improve the adhesion with the vinyl aromatic resin (A) layer in coextrusion film formation.

<Other copolymerizable monomers>
Examples of the monomer (B1-m) and the other copolymerizable monomer that can be copolymerized with the monomer (B2-m) include cyclobutene, cyclopentene, cycloheptene, cyclooctene, and tricyclo [5. 2.1.0 ^2,6 ] -3-decene and other cycloolefins. The number of carbon atoms in the cycloolefin is preferably 4-20, and more preferably 5-12. These copolymerizable monomers are useful for resin modification such as improvement in retardation, Tg adjustment, and improvement in moldability.

  Furthermore, monomers in the presence of unsaturated hydrocarbon-based polymers having an olefinically unsaturated bond in the main chain such as polybutadiene, polyisoprene, styrene-butadiene copolymer, ethylene-nonconjugated diene copolymer, polynorbornene, etc. (B1-m) and the monomer (B2-m) may be polymerized. The copolymer obtained in this case is useful as a raw material for resins having high impact resistance.

  The use ratio of the monomer (B1-m) and the monomer (B2-m) to the copolymerizable cyclic monomer or unsaturated double bond-containing compound is [monomer (B1-m) + single The monomer (B2-m)]: [copolymerizable cyclic monomer or unsaturated double bond-containing compound] is preferably 100: 0 to 50:50, more preferably 100: 0 in weight ratio. -60: 40, more preferably 100: 0-70: 30.

<Ring-opening polymerization catalyst>
The ring-opening polymerization reaction of these monomers is performed in the presence of a metathesis catalyst. The metathesis catalyst includes at least one metal compound selected from a tungsten compound, a molybdenum compound, and a rhenium compound (hereinafter referred to as “component (a)”), and a Group 1 element (for example, Li, Na, K) of the periodic table. Etc.), Group 2 elements (eg Mg, Ca etc.), Group 12 elements (eg Zn, Cd, Hg etc.), Group 13 elements (eg B, Al etc.), Group 4 elements (eg Ti, Zr etc.) Or at least one compound selected from those having at least one element-carbon bond or the element-hydrogen bond (hereinafter referred to as a compound of a Group 14 element (for example, Si, Sn, Pb, etc.)). And “(b) component”), and may contain an additive (hereinafter referred to as “(c) component”) in order to enhance the catalytic activity. There.

Specific examples of suitable metal compounds constituting the component (a) include metal compounds described in JP-A-1-240517 such as WCl ₆ , MoCl ₅ , and ReOCl ₃ .

Specific examples of the compound constituting the component (b) include n-C ₄ H ₉ Li, (C ₂ H ₅ ) ₃ A
l, (C ₂ H ₅ ) ₂ AlCl, (C ₂ H ₅ ) _1.5 AlCl _1.5 , (C ₂ H ₅ ) AlCl ₂ , methylaluminoxane, LiH and the like, the compounds described in JP-A-1-240517 are listed. Can do.

As the component (c), alcohols, aldehydes, ketones, amines and the like can be preferably used, but other compounds shown in JP-A-1-240517 can be used.
In addition, as a metathesis catalyst other than the components (a), (b), and (c), a known ruthenium compound can be used as a Grubbs catalyst.

<Hydrogenation>
The hydrogenation rate in the hydrogenated (co) polymer shown in the above <3> is usually 50% or more, preferably 70% or more, more preferably 90% or more, still more preferably 97% or more, particularly preferably 99% or more. It is.

The cyclic olefin resin (B) used in the present invention preferably has an intrinsic viscosity (η _inh ) measured in chloroform at 30 ° C. of 0.2 to 5.0 dl / g.
The average molecular weight of the cyclic olefin resin (B) is 8,000 in terms of polystyrene-reduced number average molecular weight (Mn) measured by gel permeation chromatography (GPC).
Those having a weight average molecular weight (Mw) in the range of 20,000 to 300,000 are preferred.

  Further, the glass transition temperature of the cyclic olefin-based resin (B) is preferably 100 to 250 ° C, more preferably 110 to 180 ° C, and further preferably 120 to 170 ° C in order to ensure thermal stability and coextrusion moldability. is there. In addition, the cyclic olefin resin (B) used in the present invention may be a resin composition containing the cyclic olefin resin as described above. In addition to the cyclic olefin resin, the resin composition includes an antioxidant, a heat stabilizer, a light stabilizer, a phase difference adjusting agent, an ultraviolet absorber, an antistatic agent, a dispersant, and a processability improver as necessary. , Chlorine scavengers, flame retardants, crystallization nucleating agents, antiblocking agents, antifogging agents, mold release agents, pigments, organic or inorganic fillers, neutralizing agents, lubricants, decomposition agents, metal deactivators, contamination Known additives such as an inhibitor, an antibacterial agent, other resins, and a thermoplastic elastomer can be added as long as the effects of the invention are not impaired.

Step of obtaining laminated raw film In the method for producing a laminated optical film of the present invention, the vinyl aromatic resin (A) and the cyclic olefin resin (B) described above are coextruded to form a vinyl aromatic resin layer. A laminated raw film in which (A layer) and a cyclic olefin-based resin layer (B layer) are laminated is obtained.

  A method of obtaining a laminated raw film in which a vinyl aromatic resin layer (A layer) and a cyclic olefin resin layer (B layer) are laminated is a laminated film formation by coextrusion. Specific examples include a coextrusion T-die method, a coextrusion inflation method, a coextrusion lamination method, and the like. In the present invention, a laminated optical film composed of two layers of A layer / B layer, a laminated optical film composed of three layers of A layer / B layer / A layer, and a laminated layer composed of three layers of B layer / A layer / B layer An optical film is suitably used from the viewpoint of production efficiency, ensuring strength, optical characteristics, and phase difference control. A laminated optical film composed of two layers is more preferable in terms of optical properties (transparency) and retardation control, and a laminated optical film composed of three layers is more preferable in preventing warping of the film and obtaining mechanical strength.

The extrusion temperature in the co-extrusion method is appropriately selected so that the resin has a melt viscosity suitable for extrusion film formation. Both the A layer and the B layer are preferably 200 to 350 ° C, more preferably 230 to 300 ° C, and still more preferably. Is 240-280 ° C. In addition, the temperature difference between the extrusion temperature of the A layer and the extrusion temperature of the B layer is that when both resins are contacted in the T-die or feed block, the melt viscosity changes excessively due to the temperature change, and the moldability deteriorates. Preferably, it is within 50 ° C., more preferably within 30 ° C., and further preferably within 20 ° C. The difference in melt viscosity between the resin constituting the A layer and the B layer is preferably within 5 times, more preferably within 3 times, and even more preferably within 2 times, in order to ensure moldability, particularly uniformity of the thickness of each layer. It is.

  Since the vinyl aromatic resin (A) and the cyclic olefin resin (B) used in the present invention are excellent in mutual adhesion, an adhesive layer or an adhesive layer is provided between the film layers, or corona treatment or plasma treatment. It is not necessary to perform easy adhesion treatment such as primer treatment. Sufficient adhesion strength can be obtained in a state where the A layer and the B layer are in direct contact by heat fusion by coextrusion. Even after the stretching treatment, the adhesion between the A layer and the B layer is maintained well.

  It is desirable that the obtained raw film has a uniform thickness in both the width direction and the length direction. The thickness variation causes the retardation variation of the laminated optical film to be obtained, and the display uniformity when incorporated in the liquid crystal display device is impaired. Therefore, it is desirable that there are few die lines (longitudinal streaks due to T-die lip scratches, etc.), cross marks (periodic thickness fluctuations in the length direction), and the like that cause variations in thickness. Further, it is desirable that there are few gels, foreign matters, etc. that cause display defects such as bright spots and light leaks as point-like defects. These are suppressed by using, for example, an extruder having a polymer filter, optimizing the residence time of the molten resin, reducing the pulsation of the gear pump, polishing and surface treatment of the T-die lip, smoothing of the transfer roll and release roll, and surface treatment. can do. The thickness distribution of each layer in the raw film is preferably within ± 10%, more preferably within ± 5%, and particularly preferably within ± 2%.

The laminated optical film of the present invention having a function as a stretching step retardation film can be produced by stretching the raw film. Conventionally known methods can be applied to the method of stretching the laminated optical film, but uniaxial stretching is preferably used in the direction perpendicular to the film longitudinal direction, that is, in the width direction. Specifically, a method of uniaxially stretching in the width direction using a tenter is preferable. By doing so, the excellent phase difference characteristics of the present invention can be expressed.

  In the stretching step in the production method of the present invention, the stretching temperature is the Tg of the vinyl aromatic resin (A) (hereinafter also referred to as “TgA”) and the Tg of the cyclic olefin resin (B) (hereinafter referred to as “TgB”). It is preferable to adjust the phase difference. Specifically, (the lower value of TgA and TgB) −10 (° C.) to (the higher value of TgA and TgB) +30 (° C.), preferably (the lower value of TgA and TgB) Value) −5 (° C.) to (the higher value of TgA and TgB) +20 (° C.).

The relationship between TgA and TgB preferably satisfies the following formula (iv).
| TgA−TgB | ≦ 20 (° C.) (iv)
The value of the above formula (iv) is more preferably | TgA-TgB | ≦ 15 (° C.), more preferably | TgA-TgB | ≦ 12 (° C.), particularly preferably | TgA-TgB | ≦ 10 (° C.). It is.

By setting the stretching temperature, TgA, and TgB in the above ranges, the retardation of each of the A layer and the B layer can be controlled simultaneously by stretching, and the desired characteristics of the laminated optical film (formula (i), formula (ii ), The characteristics represented by formula (iii) and formula (v), etc.) can be easily obtained. Accordingly, a liquid crystal display device having a high contrast ratio and a small color shift when the screen is viewed from an oblique direction can be realized. In addition, a laminated optical film excellent in durability at a high temperature can be obtained.

TgA and TgB are both preferably 110 ° C. or higher, more preferably 110 to 200 ° C., and particularly preferably 120 to 170 ° C. in order to ensure thermal stability and stretch processability.

  In the production method of the present invention, the draw ratio is usually 1.1 to 10 times, preferably 1.2 to 7 times, and more preferably 1.3 to 5 times. In particular, the film is preferably stretched 1.3 to 5 times by lateral uniaxial stretching that is uniaxially stretched in a direction perpendicular to the film longitudinal direction. By stretching the film uniaxially, the laminated optical film of the present invention has an optical axis (in-plane maximum refractive index direction) perpendicular to the film longitudinal direction, so the laminated optical film and the polarizer are bonded by roll-to-roll. Productivity is improved. By setting the draw ratio in the above range, the optical axis, retardation value, NZ coefficient, or distribution in the film plane of the retardation film can be suitably controlled, the contrast ratio is high, and the screen is slanted. A liquid crystal display device that has a small color shift when viewed from the direction and can display a uniform screen can be realized.

[Laminated optical film]
The laminated optical film of the present invention is formed by laminating the A layer and the B layer, and preferably laminated by directly contacting the A layer and the B layer. As a method for laminating the A layer and the B layer, in addition to the above-described coextrusion method, a known method such as a film lamination molding method such as dry lamination, a coating molding method for coating a base resin film with a resin solution, or the like. Although the method can be appropriately used, the coextrusion method is most preferable from the viewpoint of production efficiency and the like.

  The length of the laminated optical film in the longitudinal direction is preferably 50 m or more, and more preferably 100 m or more. Such a long film is usually handled as a film roll. The width of the film is preferably 1000 mm or more, more preferably 1500 mm or more, and particularly preferably 2000 mm or more.

The laminated optical film of the present invention is not particularly limited, but the film thickness is usually 10 to 400 μm, preferably 20 to 300 μm, particularly preferably 20 to 200 μm. This is desirable for adjustment.
Further, it is preferable that the thickness variation is small since the variation of the retardation value is small and the display quality is uniform. The range of thickness variation of the laminated optical film is within an average value ± 10%, preferably within an average value ± 5%, and more preferably within an average value ± 2%.

Further, the laminated optical film of the present invention may be an unstretched film or a stretched film, but has the characteristics described in formulas (i) to (iii) and preferably formula (v) described later. In order to satisfy, a stretched film is preferable.

The laminated optical film of the present invention is particularly preferably formed by the method for producing a laminated optical film of the present invention.
R450 <R550 <R650 (i)
1.0 <R650 / R550 <1.2 (ii)
70 nm ≦ R550 ≦ 150 nm (iii)
1.0 ≦ NZ ≦ 3.0 (iv)
(In the above formulas (i) to (iii), R450, R550, and R650 have a wavelength of 450 nm in this order.
It represents the in-plane retardation of the laminated optical film at 550 nm and 650 nm. The above formula (iv
) Is a coefficient represented by NZ = (nx−nz) / (nx−ny), and is a value at a wavelength of 550 nm. Here, nx is the maximum refractive index in the laminated optical film plane, ny is the refractive index in the direction orthogonal to nx in the laminated optical film plane, and nz is the refractive index in the thickness direction of the laminated optical film orthogonal to nx and ny. Represents a rate. )

Optical properties of laminated optical film In the laminated optical film of the present invention, the measured values of retardation as the laminated optical film satisfy all the properties of the following formulas (i) to (iii), preferably further represented by formula (iv) Meets the characteristics of
R450 <R550 <R650 (i)
1.0 <R650 / R550 <1.2 (ii)
70 nm ≦ R550 ≦ 150 nm (iii)
(In the above formulas (i) to (iii), R450, R550, and R650 are sequentially wavelength 450n.
m represents the in-plane retardation of the laminated optical film at 550 nm and 650 nm. )
1.0 ≦ NZ ≦ 3.0 (iv)
(In the above formula (iv), NZ is a coefficient represented by NZ = (nx−nz) / (nx−ny), and is a value at a wavelength of 550 nm. Here, nx is in the plane of the laminated optical film. (Maximum refractive index, ny represents the refractive index in the direction perpendicular to nx within the plane of the laminated optical film, and nz represents the refractive index in the thickness direction of the laminated optical film perpendicular to nx and ny.)

  In the above formula (iv), when the average refractive index of the laminated optical film is Nave, it is represented by Nave = (nx + ny + nz) / 3, and Nave is the average refractive index of each of the A layer and the B layer in the laminated optical film. It is a value obtained by weighted averaging of the rate by the thickness ratio.

The above (i) and (ii) indicate the wavelength dispersion of the phase difference, and the above (i) indicates that the longer the wavelength, the larger the in-plane phase difference, the so-called reverse wavelength dispersion. . This is a characteristic necessary for preventing the polarization state of the light passing through the laminated optical film from being different depending on the wavelength and reducing the color shift amount when the screen is viewed from an oblique direction. The value of (ii) above represents the degree of inverse wavelength dispersion. In order to reduce the amount of color shift and perform good viewing angle compensation, a larger value is desirable, preferably 1.01 to 1.18, more preferably 1.02 to 1.18. The above (iii) shows the amount of retardation in the film plane. As a retardation film for a VA mode liquid crystal display device, a compensation method combining an A plate and a C plate is known to be effective, and an in-plane retardation that effectively functions as an A plate at this time is (iii
), Preferably 75 nm to 145 nm, more preferably 75 nm to 140 nm. Satisfying the above (iii) provides a good contrast ratio. In addition, satisfying the above (i) and (ii) can reduce the color shift and further improve the contrast ratio when observed from an oblique direction. Also contributes.

Further, in order to obtain display quality uniformity, it is desirable that there is less variation in phase difference depending on the location in both the width direction and the longitudinal direction of the film. The range of variation of R650 / R550 in (ii) is preferably within ± 0.04, more preferably within ± 0.03, and particularly preferably within ± 0.02. The range of variation of R550 in (iii) above is preferably ± 7n
Within m, more preferably within ± 5 nm, particularly preferably within ± 3 nm.

  Similarly, in order to obtain display quality uniformity, it is desirable that there is less variation in the optical axis depending on the location. When the film width direction orthogonal to the film longitudinal direction is used as a reference, it is preferably within ± 2 °, more preferably ± It is within 1 °, more preferably within ± 0.7 °, and particularly preferably within ± 0.5 °.

  The above (iv) is a numerical value called an NZ coefficient, and is a numerical value representing the balance between the in-plane retardation and the thickness direction retardation of the laminated optical film. In order to calculate the NZ coefficient, the in-plane retardation and the oblique direction retardation of the laminated optical film (usually the value when entering from a polar angle of 40 ° with a slow axis inclination) are measured, and the total film thickness and the film average By calculating numerically using the refractive index, nx, ny, and nz are obtained, and determined as NZ = (nx−nz) / (nx−ny). However, in the case of the laminated optical film of the present invention, since the average refractive indexes of the A layer and the B layer are different, Nave cannot be directly measured and determined.

  Therefore, in the present invention, for convenience, the average refractive index Nave of the laminated optical film is a value obtained by weighted average of the average refractive indexes of the A layer and the B layer by the thickness ratio. That is, when the average refractive index of the A layer is NaveA, the thickness is dA (μm), the average refractive index of the B layer is NaveB, and the thickness is dB (μm), Nave = (dA × NaveA + dB × NaveB) / (dA + dB) Nx, ny, and nz are numerically calculated to determine NZ.

  The thicknesses dA and dB of each layer are measured by peeling each layer and measuring the thickness of each layer with a contact micrometer, or observing a cross section of the laminated optical film with a microscope, or a known non-contact measurement method such as an optical interference method. It is measured using a film thickness measuring device. Among them, the optical interference type film thickness measurement is preferable because the measurement accuracy is good, it is nondestructive, and it can be measured both online and offline.

  In addition, when there are two or more A layers and / or B layers, respectively, for example, in the case of a three-layer configuration of A layer / B layer / A layer, dA is a value obtained by adding the thicknesses of two or more A layers, dB is the sum of the thicknesses of two or more B layers.

  The NZ coefficient closer to 1 is closer to the positive A plate, which is preferable because it matches the compensation method combining the A plate and the C plate, which is a compensation method for the VA liquid crystal, and the contrast ratio is improved. Preferably it is 1.0-2.5, More preferably, it is 1.0-2.0. A film having an NZ coefficient of less than 1 does not have reverse wavelength dispersion.

Optical characteristics of each layer (in-plane retardation)
The A layer and the B layer constituting the laminated optical film of the present invention have desirable retardation values and retardation wavelength dispersion properties, respectively. However, since it is impossible to measure the phase difference of each of the A layer and the B layer in the laminated state, the A layer and the B layer are peeled off from the laminated optical film, and the phase difference is measured separately, or the A layer and the B layer are separated. Calculate the retardation value of the A layer and the B layer from the retardation wavelength dispersion of each of the constituting polymers and the retardation wavelength dispersion of the laminated optical film, or laminate the optical film of only the A layer and the film of only the B layer. The properties of each layer can be confirmed by stretching under the same conditions as the film and measuring the phase difference separately. When the in-plane retardation of the A layer at wavelengths of 450 nm and 550 nm is R450A and R550A, and the in-plane retardation of the B layer at wavelengths of 450 nm and 550 nm is R450B and R550B, each layer satisfies the following conditions (vi) to (x). It is adjusted as follows.
R450B / R550B ≦ 1.04 (v)
200 nm ≦ R550B ≦ 400 nm (vi)
1.04 <R450A / R550A (vii)
100 nm ≦ R550A ≦ 300 nm (viii)
R550B> R550A (ix)

When the A layer and the B layer satisfy the above formulas (v) to (ix), the above formula (
It is possible to satisfy i) to (iii) or (i) to (iv), reduce the color shift when the liquid crystal display device is viewed from an oblique direction, and improve the contrast ratio at the same time. In addition, since A layer and B layer differ in the positive / negative of intrinsic birefringence, when A layer and B layer are extended | stretched simultaneously as a laminated optical film, the maximum refractive index direction of A layer and B layer is mutually orthogonal. For this reason, the in-plane retardations cancel each other, and the in-plane retardation R550 of the laminated optical film is represented by R550B-R550A. From the above formula (ix), the optical axis of the laminated optical film becomes a direction orthogonal to the longitudinal direction of the film, and roll-to-roll adhesion with the polarizer becomes possible, thereby improving the productivity of the polarizing plate.

By using the method for producing a laminated optical film of the present invention and stretching in the film width direction at the above-described stretching temperature and stretch ratio, each layer can satisfy the above (v) to (ix) by one stretching process. At the same time, the entire laminated optical film can satisfy the above (i) to (iii) or (i) to (iv). For this reason, the manufacturing method of the laminated optical film of this invention is very excellent in productivity.

  The above (v) and (vii) represent the wavelength dispersion of the retardation of each layer. R450A / R550A of the A layer is larger than R450B / R550B of the B layer, and the wavelength dispersion of the B layer is flat chromatic dispersion that does not change much for each wavelength, or inverse chromatic dispersion in which the phase difference increases as the wavelength increases. is there. On the other hand, the wavelength dispersion of the A layer is so-called positive wavelength dispersion in which the phase difference decreases as the wavelength increases compared to the B layer. When the A layer and the B layer satisfy this characteristic, the laminated optical film satisfies the characteristics of the above formulas (i) and (ii) when the phase difference is canceled between the A layer and the B layer.

  When there are two or more A layers and / or B layers, for example, in the case of a three-layer configuration of A layer / B layer / A layer, R450A and R550A add up the phase difference of two or more A layers. R450B and R550B are values obtained by summing the phase differences of two or more B layers.

  In addition, it is desirable for the A layer and the B layer that there is little variation in retardation depending on the location in order to obtain display quality uniformity. The variation range of (v) and (vii) is preferably within ± 0.03, more preferably within ± 0.02, and particularly preferably within ± 0.01. The range of variation of R550A and R550B represented by (vi) and (viii) is preferably within ± 7 nm, more preferably within ± 5 nm, and particularly preferably within ± 3 nm.

  Also, it is desirable that the optical axis variation of each layer is small depending on the location in order to obtain display quality uniformity. The optical axis of the A layer is preferably within ± 2 degrees, more preferably within ± 1 degree, further preferably within ± 0.7 degrees, and particularly preferably within ± 0.5 degrees, based on the film width direction. is there. The optical axis of layer B is preferably within ± 2 degrees, more preferably within ± 1 degree, even more preferably within ± 0.7 degrees, and particularly preferably within ± 0.5 degrees, based on the longitudinal direction of the film. is there.

  In addition, in order to obtain display quality uniformity, it is desirable that the thickness variation depending on the location of both the A layer and the B layer is small because the variation of the phase difference is small. The variation ranges of dA and dB are each within an average value ± 10%, preferably within an average value ± 5%, and more preferably within an average value ± 2%, similarly to the range of thickness variation of the entire laminated optical film.

The thickness ratio of the A layer and the B layer is not particularly limited as long as the optical characteristics of each layer and the entire laminated optical film are within a desired range. In order to develop a predetermined retardation, the thickness ratio of the A layer is preferably 20 to 90%, more preferably 30 to 80%, and further preferably 40 to 80% of the entire laminated optical film. (When there are two or more A layers and / or B layers, the thicknesses of the respective layers are summed up and expressed as a thickness ratio of the entire laminated optical film of all A layers)
Similarly, in order to obtain display quality uniformity, it is desirable that there is less variation in NZ depending on the location. The variation range of NZ is within an average value ± 0.3, preferably within an average value ± 0.2, and more preferably within an average value ± 0.1.

Furthermore, in order for the NZ coefficient of the laminated optical film of the present invention to satisfy the above formula (v), the A layer and the B layer constituting the laminated optical film each have a desirable NZ coefficient range. However, since the NZ coefficient of each of the A layer and the B layer cannot be obtained in the laminated state, the A layer and the B layer are peeled off from the laminated optical film and the phase difference is separately measured to obtain the NZ coefficient, or only the A layer is obtained. The film and the film of only the B layer are stretched under the same conditions as the laminated optical film, and the phase difference is separately measured to obtain the approximate NZ coefficient of each layer. When the NZ coefficient of the A layer is NZA and the NZ coefficient of the B layer is NZB, the following conditions (x) to (xi) are satisfied.
1.0 ≦ NZB ≦ 1.7 (x)
−1.0 ≦ NZA ≦ 0 (xi)
[In the above formula (x), NZB is a coefficient represented by NZB = (nxB-nzB) / (nxB-nyB), and is a value at a wavelength of 550 nm. Here, nxB is the maximum refractive index in the plane of the B layer, nyB is the refractive index in the direction orthogonal to nxB in the plane of the B layer, and nzB is the refractive index in the thickness direction of the B layer orthogonal to nxB and nyB. The rate is expressed as NaveB = (nxB + nyB + nzB) / 3. In the above formula (xi), NZA is a coefficient represented by NZA = (nxA−nzA) / (nxA−nyA), and is a value at a wavelength of 550 nm. Here, nxA is the maximum refractive index in the plane of the A layer, nyA is the refractive index in the direction orthogonal to nyA in the plane of the A layer, and nzA is the refractive index in the thickness direction of the A layer orthogonal to nxA and nyA. The rate is expressed as NaveA = (nxA + nyA + nzA) / 3. ]

The above formula (x) corresponds to a phase difference that is manifested when the cyclic olefin-based resin layer (B) is laterally stretched, where nxB is the stretching direction, ie, the film width direction, and nyB is orthogonal to the stretching direction, ie, the film longitudinal direction. . In the refractive index ellipsoid, it is generally called a positive B plate. The above formula (xi) corresponds to a phase difference developed when the vinyl aromatic resin layer is laterally stretched. NxA is orthogonal to the stretching direction, that is, the film longitudinal direction, and nyA is the stretching direction, that is, the film width direction. In the refractive index ellipsoid, it is generally called a negative B plate. The NZ of the laminated optical film cannot be obtained by simple calculation from NZA and NZB, and is related as a result of the change in the polarization state in the A layer and the change in the polarization state in the B layer by Poincare sphere display.

  NZA and NZB have a desirable range, preferably (NZA + NZB) /2=0.1 to 0.8, more preferably (NZA + NZB) /2=0.2 to 0.8, more preferably ( NZA + NZB) /2=0.3 to 0.7. When NZA and NZB satisfy this range, the laminated optical film exhibits reverse wavelength dispersion when viewed from any direction, and a predetermined phase difference cannot be obtained due to the optical axis shift of each layer when viewed from any direction. No problem occurs, leading to improved panel characteristics due to reduced color shift. A smaller NZB leads to improved panel characteristics, preferably 1.0 to 1.6, more preferably 1.0 to 1.5. At the same time, a larger NZA leads to improved panel characteristics, preferably -0.6 to 0, more preferably -0.5 to 0. By setting the NZ coefficient of each layer in the above range, it is possible to have a predetermined phase difference even when observed from an oblique direction, to reduce the color shift at an oblique viewing angle of the liquid crystal display device, and simultaneously improve the contrast ratio. Is possible.

  Further, in order to obtain uniformity in display quality, it is desirable that both NZA and NZB have less variation depending on the location. The variation ranges of NZA and NZB are each preferably within an average value ± 0.2, and more preferably within an average value ± 0.1.

[Polarizer]
The polarizing plate of the present invention has the laminated optical film of the present invention having a function as a retardation film on at least one surface, and the laminated optical film of the present invention is laminated on at least one surface of a polarizer (polarizing film). It is desirable to have the configuration described above. As the polarizer constituting the polarizing plate of the present invention, for example, a film made of polyvinyl alcohol (PVA) or a polymer obtained by formalizing a part of PVA is used, and a dichroic substance made of iodine or a dichroic dye is used. A film obtained by performing a dyeing process, a stretching process, a crosslinking process, and the like in an appropriate order and method, and transmits linearly polarized light when natural light is incident thereon. In particular, those having a high light transmittance and an excellent degree of polarization are preferably used.

  In general, the thickness of the polarizer constituting the polarizing plate is preferably 5 to 80 μm, but is not limited to this in the present invention. Moreover, as a polarizer, you may use another thing other than the said PVA-type film, if the same characteristic is expressed. For example, a film made of a cyclic olefin resin may be subjected to dyeing treatment, stretching treatment, cross-linking treatment, etc. in an appropriate order or method, or may be obtained by coating and orienting a solution of a dichroic substance. Alternatively, a wire grid polarizer may be used.

  Usually, a polarizing plate is composed of a polarizer, a retardation film, and a protective film, but in the present invention, as a retardation film that constitutes a polarizing plate, a laminated optical film is bonded to at least one surface of the polarizer. Or it bonds and uses through an adhesive. The laminated optical film may be bonded to the polarizer on the A layer side, or may be bonded to the polarizer on the B layer side. In such a polarizing plate, the retardation film is excellent in properties such as heat resistance, moisture resistance and chemical resistance and has a sufficient function as a protective film. A protective film may not be separately laminated on the surface on which the laminated optical film of the invention is laminated. When the polarizing plate of the present invention has a configuration in which the laminated optical film of the present invention having a function as a retardation film is laminated only on one side of the polarizer, the other side of the polarizer is, for example, triacetyl. A known protective film such as cellulose (TAC), a cyclic olefin resin film, or an acrylic resin film may be laminated.

  The laminated optical film and the polarizer of the present invention are bonded to each other, and the protective film and the polarizer are bonded to each layer using a known adhesive or pressure sensitive adhesive such as a pressure sensitive adhesive, a thermosetting adhesive, or a photocurable adhesive. It can manufacture suitably by adhering via. As the pressure-sensitive adhesive and adhesive, those having excellent transparency are preferable. Specifically, natural rubber, synthetic rubber, vinyl acetate / vinyl chloride copolymer, polyvinyl ether, polyvinyl alcohol, acrylic resin, modified polyolefin resin, etc. A curable adhesive prepared by adding a curing agent such as an isocyanate group-containing compound to the resin having a functional group such as a hydroxyl group or an amino group; a polyurethane-based dry laminate adhesive; a synthetic rubber-based adhesive; Examples thereof include an epoxy adhesive.

  In addition, the polarizing plate of the present invention preferably further includes at least one layer selected from an antireflection layer and an antiglare layer, and is preferably provided outside the protective film surface on the side opposite to the polarizer.

  These layers are formed by applying a thermosetting resin composition or a photocurable resin composition by a known coating method such as gravure coating, die coating, or slot coating, drying as necessary, and then curing. can do. These layers may be provided directly on the protective film, or may be formed by providing a base film on the protective film and bonding the base film to the protective film. Moreover, the said layer may be formed before bonding a protective film or a base film to a polarizer, and the said layer may be formed after bonding to a polarizer.

  The antireflection layer is usually composed of a low refractive index layer, and may further have a laminated structure of a low refractive index layer and a high refractive index layer to further improve the antireflection performance, and further ensure scratch resistance. Therefore, you may have a hard-coat layer. The lamination order is preferably from the side close to the protective film, preferably in the order of hard coat layer / high refractive index layer / low refractive index layer. If necessary, an intermediate refractive index layer may be provided between the low refractive index layer and the high refractive index layer, or between the hard coat layer and the high refractive index layer. These layers can be formed by sputtering, vapor deposition, or the like, but are preferably formed by applying the curable composition as described above.

Examples of the composition for forming the low refractive index layer and the high refractive index layer include known curable compositions. For example, the binder resin contains at least one epoxy resin, phenol resin, melamine resin, alkyd resin, cyanate resin, acrylic resin, polyester resin, urethane resin, siloxane resin, and the like, The composition for forming a low refractive index layer contains a fluorine-containing compound, and the composition for forming a high refractive index layer is a high refractive index inorganic particle, for example, a metal such as silica, alumina, titania, zirconia, ceria, scandia, magnesium fluoride, etc. Contains oxide particles.

  The refractive index and thickness of the low refractive index layer and the high refractive index layer are used within a known range, but in order to enhance the antireflection effect, the refractive index of the low refractive index layer (average refractive index at 25 ° C. and wavelength 589 nm) is 1.45 or less, and the thickness of the low refractive index layer is preferably 50 to 300 nm. The refractive index of the high refractive index layer (average refractive index at 25 ° C. and wavelength 589 nm) is preferably a refractive index larger by 0.05 or more than the refractive index of the low refractive index layer, and the thickness is 50 to 10, 000 nm is preferable.

  A known material can be used as a constituent material of the hard coat layer. Examples of such a material include one or more of a siloxane resin, an acrylic resin, a melamine resin, an epoxy resin, and the like, and inorganic particles such as a metal oxide may be included. The hard coat layer may have an effect as an antiglare layer described later.

The thickness of the hard coat layer is not particularly limited, but is preferably 2 to 10 μm.
As the antiglare layer, a layer that exhibits antiglare properties by having irregularities on the layer surface is usually used, and a layer having a surface centerline average roughness of 0.1 to 1.0 μm is preferable. As the composition for forming the antiglare layer, a curable composition containing organic particles and / or inorganic particles is preferably used. As the binder resin used for the curable composition, the binder resin of the curable composition used for forming the antireflection film described above can be used. As preferable anti-glare properties, the layer has a Haze of 5 to 65% and a total light transmittance of 80 to 98%.

[Liquid Crystal Display]
The liquid crystal display device of the present invention has the polarizing plate of the present invention, and preferably has the polarizing plate of the present invention. The liquid crystal display device of the present invention is a laminated optical film or polarizing plate having a high contrast ratio when the screen is viewed from an oblique direction, a small color shift amount when the screen is viewed from an oblique direction, and small optical unevenness. Therefore, it can display evenly and has excellent durability that can withstand long-term use in harsh environments, and there is little reflection of external light.

EXAMPLES Hereinafter, although this invention is demonstrated further more concretely based on an Example, this invention is not limited to these Examples. In the following Examples and Comparative Examples, “parts” and “%” mean “parts by weight” and “% by weight” unless otherwise specified. Moreover, room temperature is 25 degreeC.
In the following examples and comparative examples, various measurements and evaluations were performed as follows.

[Polymerization reaction rate]
Place the weighed polymerization reaction solution in an aluminum container, heat to a constant temperature on a hot plate heated to 300 ° C., remove residual monomer and solvent, measure the weight of the remaining polymer, and calculate the theoretical weight. The reaction rate was determined from the ratio to the combined production amount.

[Hydrogen addition rate]
The nuclear magnetic resonance spectrometer (NMR) was an AVANCE 500 manufactured by Bruker, and the measurement solvent was ¹ H-NMR with d-chloroform. 5.1-5.8 ppm of vinylene groups, 3
. The hydrogenation rate was calculated after calculating the monomer composition from the integrated value of 7 ppm methoxy group and 0.6 to 2.8 ppm aliphatic proton.

[Glass transition temperature (Tg)]
Using a differential scanning calorimeter (manufactured by Seiko Instruments Inc., trade name: DSC6200), the temperature was measured at a rate of temperature increase of 20 ° C./min according to Japanese Industrial Standard K7121.

[Weight average molecular weight (Mw) and molecular weight distribution (Mw / Mn)]
Gel permeation chromatography (Tosoh Co., Ltd. HLC-8220GPC, Column: Tosoh Co., Ltd. guard column H _XL- H, TSK gel G7000H _XL , TSKgel GMH _XL , TSK gel G2000H _XL , sequentially connected, solvent: Tetrahydrofuran, flow rate: 1 mL / min, sample concentration: 0.7 to 0.8% by weight, injection amount: 70 μL, measurement temperature: 40 ° C., detector: RI (40 ° C.), standard material: manufactured by Tosoh Corporation Using TSK standard polystyrene), the weight average molecular weight (Mw) and molecular weight distribution (Mw / Mn) were measured. The Mn is a number average molecular weight.

[Logarithmic viscosity]
Using an Ubbelohde viscometer, sample concentration 0.5 g / dL in chlorobenzene, temperature 30
The logarithmic viscosity was measured at a temperature of ° C.

[Thickness]
The cross section of the laminated optical film was measured with an optical microscope. If the cross section is not suitable for microscopic observation, the cross section is embedded in an epoxy resin, sliced using a microtome RV-240 manufactured by Daiwa Koki Co., Ltd. did.

[Phase difference]
It measured using the automatic birefringence meter (The Oji Scientific Instruments Co., Ltd. make, KOBRA-21ADH). The in-plane retardations R450, R550, and R650 at wavelengths of 450 nm, 550 nm, and 650 nm are obtained by regression calculation of measured values at wavelengths of 478.8 nm, 546.0 nm, 629.3 nm, and 747.3 nm using Cauchy's equation. It was. The NZ coefficient was determined from the in-plane retardation of the film and the slow axis inclination, the oblique retardation from a polar angle of 40 degrees, the film thickness, and the film average refractive index.

[Single transmittance, degree of polarization]
The single transmittance and polarization degree of the polarizing plate were measured using V-7300 manufactured by JASCO Corporation.

[Measurement of contrast ratio of liquid crystal display]
Using ELZIM "EZContrast-XL88", the brightness, viewing angle, contrast ratio, and color shift of the liquid crystal panel were measured in a dark room with an illuminance of 1 lx or less.

[Adhesion between laminated optical film layers]
Adhesion was confirmed by attaching the laminated optical film to a glass plate with a double-sided tape, putting a cutter blade between each layer and peeling it, and evaluated it according to the following criteria.
A: The cutter blade does not enter between the layers and does not peel off.
○: The cutter blade enters between the layers, and the peeled portion can be produced, but does not peel continuously.
X: The cutter blade enters the interlayer and peels continuously from the peeled portion.

[Adhesion of antireflection layer and antiglare layer]
Using cellophane tape (“CT24”, manufactured by Nichiban Co., Ltd.), a cross-cut peel test was performed by the method described in JIS-D0202, and the evaluation was performed according to the following criteria.
A: 100 cells out of 100 cells.
○: The number of remaining cells is 90 cells or more out of 100 cells.
X: The number of remaining cells is less than 90 cells in 100 cells.

[Environmental test (change in phase difference)]
About the produced laminated optical film, the temperature was changed to 95 ° C. for 500 hours as a dry heat test, 85 ° C. as a wet heat test, 500 hours at 85% relative humidity, and as a heat shock test for 30 minutes at −40 ° C. and 30 minutes at 85 ° C. Under the three conditions of 200 cycles as one cycle, the amount of change (%) in the in-plane retardation was measured before and after, and evaluated according to the following criteria.
A: The amount of change in phase difference is within ± 2% in all three conditions, and there is no change in appearance.
○: The amount of change in phase difference is within ± 3% for all three conditions, and there is no change in appearance.
X: The amount of change in phase difference exceeds ± 3% under any condition. Or visual changes such as deformation, whitening, cracks, and delamination are observed.

[Environmental test (change in coating film)]
About the protective film which provided the antireflection layer and the glare-proof layer, it put on the said 3 conditions, examined the external appearance change of the said layer before and after the test, and the presence or absence of delamination, and evaluated by the following references | standards.
A: No change in appearance in all three conditions.
○: Slight color changes such as whitening and yellowing are observed.
X: Obvious changes in appearance such as visual deformation, cracks and delamination are observed.

[Reflectance]
The surface without the anti-reflection layer of the protective film provided with the anti-reflection layer (before being bonded to the polarizer or peeled off from the polarizing plate) is painted with black spray, and the spectral reflectance measuring device (large sample chamber integrating sphere) The reflectance was measured from the antireflection layer side in the wavelength range of 380 to 780 nm with a spectrophotometer U-3410 incorporating Hitachi 150-09090 (manufactured by Hitachi, Ltd.) and evaluated. Specifically, the reflectance of the antireflection laminate (antireflection film) was measured in the range of 380 to 780 nm, with the reflectance of the aluminum deposited film as a reference (100%).

[Haze (cloudiness value) and total light transmittance]
About the protective film in a state where it is bonded to the polarizer or peeled off from the polarizing plate, the haze and the total light transmittance are measured by the method described in JIS K7105 using a haze meter HZ-2 (manufactured by Suga Test Instruments Co., Ltd.). Was measured.

[Synthesis Example 1] Synthesis of vinyl aromatic resin (A1) In a glass flask equipped with a stirrer, a condenser and a thermometer, 127.87 g (1.23 mol) of styrene, 13.33 g (0.136 mol) of maleic anhydride, Toluene 75 g as a solvent and 1,1′-azobis (cyclohexane-1-carbonitrile) 0.67 g (2.7 mmol) as a radical initiator were added, heated to 90 ° C., and reacted for 15 hours. A part of this polymerization solution was taken out and the reaction rate was measured to be 85%. Moreover, it was Mw = 129,900 and Mw / Mn = 2.00 when the molecular weight was measured.

  The obtained polymerization reaction solution was diluted with tetrahydrofuran and coagulated in a large amount of methanol to recover and purify the polymer, followed by drying for 2 days in an 80 ° C. vacuum dryer. When the molecular weight and logarithmic viscosity of the obtained polymer were measured, Mw = 131,910 (Mw / Mn = 1.88), logarithmic viscosity η = 0.44 dL / g, and the yield was 80%. The copolymer composition ratio determined by NMR was as prepared. The obtained polymer was a styrene-maleic anhydride copolymer, and the glass transition temperature was 122 ° C. Hereinafter, the obtained vinyl aromatic copolymer (resin) is referred to as A1.

[Synthesis Example 2] Synthesis of vinyl aromatic resin (A4) In a glass flask equipped with a stirrer, a condenser and a thermometer, 145.6 g (1.40 mol) of styrene, 75 g of toluene as a solvent, and 1, 1 as a radical initiator 0.67 g (2.7 mmol) of 1′-azobis (cyclohexane-1-carbonitrile) was added, heated to 90 ° C., and reacted for 15 hours. A part of this polymerization solution was taken out and the reaction rate was measured to be 93%.

  The obtained polymerization reaction solution was diluted with tetrahydrofuran and coagulated in a large amount of methanol to recover and purify the polymer, followed by drying for 2 days in an 80 ° C. vacuum dryer. When the molecular weight and logarithmic viscosity of the obtained polymer were measured, Mw = 168,300 (Mw / Mn = 1.68), logarithmic viscosity η = 0.42 dL / g, and the yield was 87%. The obtained polymer was polystyrene and the glass transition temperature was 102 ° C. Hereinafter, the obtained vinyl aromatic copolymer (resin) is referred to as A4.

[Synthesis Example 3] Synthesis of Cyclic Olefin Resin (B1) 8-Methyl-8-methoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] −
215 parts of 3-dodecene, 35 parts of bicyclo [2.2.1] hept-2-ene, 18 parts of 1-hexene (molecular weight regulator) and 750 parts of toluene (solvent for ring-opening polymerization reaction) The reaction vessel was purged with nitrogen, and this solution was heated to 60 ° C. Next, 0.62 parts of a toluene solution of triethylaluminum (1.5 mol / l) as a polymerization catalyst and tungsten hexachloride modified with t-butanol and methanol (t-butanol: methanol: tungsten) were added to the solution in the reaction vessel. = 0.35 mol: 0.3 mol: 1 mol) of toluene solution (concentration: 0.05 mol / l) was added to 3.7 parts, and this solution was heated and stirred at 80 ° C. for 3 hours to open the ring. Polymerization reaction was performed to obtain a ring-opening polymer solution. The polymerization conversion rate in this polymerization reaction was 97%, and the obtained ring-opening polymer had a logarithmic viscosity measured in chloroform at 30 ° C. of 0.75 dl / g.

1,000 parts of the ring-opening polymer solution thus obtained was charged into an autoclave, and 0.12 part of RuHCl (CO) [P (C ₆ H ₅ ) ₃ ] ₃ was added to the ring-opening polymer solution. Then, the hydrogenation reaction was performed by heating and stirring for 3 hours under the conditions of a hydrogen gas pressure of 100 kg / cm ² and a reaction temperature of 165 ° C. After cooling the obtained reaction solution (hydrogenated polymer solution), the hydrogen gas was released. This reaction solution was poured into a large amount of methanol to separate and recover a coagulated product, which was dried to obtain a hydrogenated polymer (hereinafter referred to as cyclic olefin resin (B1)).

  The resin B1 thus obtained had a hydrogenation rate of 99.9%, a glass transition temperature of 125 ° C., a number average molecular weight (Mn) of 32,000, a weight average molecular weight (Mw) of 137,000, and a molecular weight. The distribution (Mw / Mn) was 4.29, and the logarithmic viscosity was 0.69 dl / g.

[Synthesis Example 4] Synthesis of Cyclic Olefin Resin (B2) Tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene 53 parts and 8-ethylidenetetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene (46 parts) and tricyclo [
4.3.0.1 ^2,5 ] -deca-3,7-diene and 66 parts of 1-hexene (molecular weight regulator) and toluene as a solvent for the ring-opening polymerization reaction. A hydrogenated polymer (hereinafter referred to as cyclic olefin-based resin (B2)) was obtained in the same manner as in Synthesis Example 1 except that cyclohexane was used instead of.

  With respect to the obtained resin B2, the hydrogenation rate was 99.9%, the glass transition temperature (Tg) was 125 ° C., Mn was 30,000, Mw was 122,000, and the molecular weight distribution (Mw / Mn) was 4.07. The logarithmic viscosity was 0.63 dl / g.

[Preparation Example 1] Preparation of aqueous adhesive 250 parts of distilled water was charged into a reaction vessel, 90 parts of butyl acrylate, 8 parts of 2-hydroxyethyl methacrylate, 2 parts of divinylbenzene, and potassium oleate 0 1 part was added, and this was stirred with a stirring blade made of Teflon (registered trademark) and dispersed. After replacing the inside of the reaction vessel with nitrogen, the temperature of the system was raised to 50 ° C., and 0.2 part of potassium persulfate was added to initiate polymerization. After 2 hours, 0.1 part of potassium persulfate was further added, the system was heated to 80 ° C., and the polymerization reaction was continued for 1 hour to obtain a polymer dispersion.

  Next, by using an evaporator, the polymer dispersion liquid is concentrated until the solid content concentration becomes 70%, whereby an aqueous adhesive (adhesive having a polar group) composed of an aqueous dispersion of an acrylic ester polymer. Got.

  The acrylic ester polymer constituting the aqueous adhesive thus obtained has a MPC of 69,000 and Mw of 135,000 by GPC, and a logarithmic viscosity measured in chloroform at 30 ° C. is 1 .2 dL / g.

[Preparation Example 2] Preparation of hard coat layer coating solution In a container shielded from ultraviolet rays, 86 parts of a methyl ethyl ketone / isopropyl alcohol dispersion of silica particles having an average particle size of 20 nm whose surface is modified with an unsaturated group (solid content) 30 parts), 65 parts of dipentaerythritol hexaacrylate, 5 parts of 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropan-1-one, and 44 parts of MIBK are stirred at 50 ° C. for 2 hours. As a result, a uniform coating solution for the hard coat layer was obtained. 2 g of this coating solution was weighed on an aluminum dish, dried on a hot plate at 120 ° C. for 1 hour, and weighed to determine the solid content, which was 50% by weight.

[Preparation Example 3] Preparation of coating solution for low refractive index layer A stainless steel autoclave with an internal volume of 2 liters equipped with a magnetic stirrer was sufficiently replaced with nitrogen gas, and then 400 g of ethyl acetate, 53.2 g of perfluoro (propyl vinyl ether), ethyl 36.1 g of vinyl ether, 44.0 g of hydroxyethyl vinyl ether, 1.00 g of lauroyl peroxide, 6.0 g of azo group-containing polydimethylsiloxane (VPS1001 (trade name), manufactured by Wako Pure Chemical Industries, Ltd.) and nonionic reactive emulsifier After charging 20.0 g (NE-30 (trade name), manufactured by Asahi Denka Kogyo Co., Ltd.) and cooling to -50 ° C. with dry ice-methanol, oxygen in the system was removed again with nitrogen gas.

Next, 120.0 g of hexafluoropropylene was charged, and the temperature increase was started. The pressure when the temperature in the autoclave reached 60 ° C. was 5.3 × 10 ⁵ Pa. Then 7
The reaction was continued with stirring at 0 ° C. for 20 hours. When the pressure dropped to 1.7 × 10 ⁵ Pa, the autoclave was cooled with water to stop the reaction. After reaching room temperature, unreacted monomers were released and the autoclave was opened to obtain a polymer solution having a solid content concentration of 26.4%. The obtained polymer solution was put into methanol to precipitate a polymer, washed with methanol, and vacuum dried at 50 ° C. to obtain 220 g of a hydroxyl group-containing fluoropolymer.

  Subsequently, in a 1 liter separable flask equipped with a magnetic stirrer, a glass condenser, and a thermometer, 50.0 g of the hydroxyl group-containing fluoropolymer and 2,6-di-t-butyl as a polymerization inhibitor were used. 0.01 g of methylphenol and 370 g of methyl isobutyl ketone (MIBK) were charged, and the mixture was stirred at 20 ° C. until the hydroxyl group-containing fluoropolymer was dissolved in MIBK and the solution became transparent and uniform.

Next, 15.1 g of 2-methacryloyloxyethyl isocyanate was added to this system and stirred until the solution became homogeneous, then 0.1 g of dibutyltin dilaurate was added to start the reaction, and the temperature of the system was changed to 55 to 55. A MIBK solution of an ethylenically unsaturated group-containing fluoropolymer was obtained by maintaining the temperature at 65 ° C. and continuing stirring for 5 hours. The solid content of this solution was determined to be 15.0% by weight.

  507 g (76 g as solid content) of MIBK solution of the above-mentioned ethylenically unsaturated group-containing fluoropolymer, and 65.6 g (as solid content) of methyl ethyl ketone dispersion of silica particles having an average particle size of 45 nm modified with unsaturated groups on the surface. 21 g), 3 g of 1-hydroxycyclohexyl phenyl ketone (Irgacure 184, manufactured by Ciba Specialty Chemicals) and MIBK 1424.4 g as a photopolymerization initiator were charged into a glass separable flask equipped with a stirrer at room temperature for 1 hour. By stirring, a uniform coating solution for a low refractive index layer was obtained. The solid content concentration of this coating solution was determined to be 5.0% by weight.

[Preparation Example 4] Preparation of coating solution for antiglare layer / hard coat layer Pentaerythritol triacrylate (manufactured by Toa Gosei Co., Ltd., trade name “Aronix M-305” (specific gravity 1.179)) 90.0 parts, 10.0 parts by mass of silica particles having an average particle size of 1.5 μm (trade name “Nip seal E-200” (specific gravity 2.150), manufactured by Tosoh Silica Co., Ltd.), and photopolymerization initiator 1-hydroxycyclohexyl phenyl ketone 5.0 parts (trade name “Irgacure 184” manufactured by Ciba Specialty Chemicals Co., Ltd.) was added to propylene glycol monomethyl ether and mixed to prepare a coating solution having a solid content concentration of 30% by weight.

[Production Example 1] Production of Polarizer A roll-shaped polyvinyl alcohol (hereinafter also referred to as “PVA”) film having a film thickness of 120 μm has an iodine concentration of 0.03% by weight and a potassium iodide concentration of 0. After continuously uniaxially stretching (pre-stretching) in the longitudinal direction at a stretching ratio of 3 times in a dye bath of 5% by weight of 30 ° C. aqueous solution, the boric acid concentration is 5% by weight and the potassium iodide concentration is 8 In a 55% C. cross-linking bath of an aqueous solution of wt%, the film was further uniaxially stretched (post-stretched) in the longitudinal direction at a stretch ratio of 2 and dried to obtain a take-up roll-shaped polarizer.

[Production Example 2] Production of optical film (negative C plate) and polarizing plate The film roll (150 μm) of the cyclic olefin resin (B1) obtained in Synthesis Example 3 was stretched at 133 ° C. and stretched at 1.6 times. The film was stretched longitudinally, and then stretched transversely by a tenter at a stretching temperature of 135 ° C. and a stretching ratio of 2.4 times to obtain a stretched film having a thickness of 68 μm. In-plane retardation R550 of the obtained stretched film was 0 to 2 nm, and average Rth was 190 nm. (Rth is one of the indices representing the thickness direction retardation, and is represented by {(nx + ny) / 2−nz} × d. Nx is the maximum in-plane refractive index at the optical film measurement point, and ny is the surface. (Wherein nz represents the refractive index in the thickness direction of the stretched film perpendicular to nx and ny, and d represents the film thickness (nm) at the measurement point.)

  This film was made to have a roll-shaped film on one side of the polarizer obtained in Production Example 1, and both were continuously pasted using the aqueous adhesive obtained in Preparation Example 1, and the other side of the polarizer was adhered. A saponified 80 μm-thick triacetyl cellulose (hereinafter also referred to as “TAC”) film was attached to the surface using an adhesive composed of a 5% PVA aqueous solution to obtain a polarizing plate (P0). . The obtained polarizing plate had a single transmittance of 42.1% and a polarization degree of 99.9%.

[Example 1]
<Manufacture of laminated optical film (F1)>
The cyclic olefin resin (B1) pellets and the vinyl aromatic resin (A1) pellets were each dried at 100 ° C. for 5 hours using a hot air dryer in which dry air was passed. These pellets were co-extruded under the conditions of a molten resin temperature of 260 ° C. and a T-die lip opening width of 600 mm using two series of melt extruders having a 65 mmφ screw and a 50 mmφ screw, thereby obtaining a B1 layer (150 μm) / An unstretched laminated optical film roll having a configuration of A1 layer (140 μm) was obtained.

  This laminated optical film roll was transversely stretched with a tenter at a stretching temperature of 128 ° C. and a draw ratio of 2.0 times to obtain a laminated optical film (F1) having a thickness of 148 μm. The in-plane retardation of the obtained laminated optical film was R450 = 79 nm, R550 = 90 nm, R650 = 96 nm, and NZ = 1.65. When the adhesiveness of this laminated optical film was confirmed, the adhesiveness was good without peeling. As a result of the environmental test, the change amount of the phase difference was within ± 2% in all three conditions, and no change in the appearance was observed.

<Production of Polarizing Plate (P1) and Evaluation of Liquid Crystal Display>
For the obtained laminated optical film (F1), roll-like films are aligned on one side of the polarizer obtained in Production Example 1 (the stretching direction which is the absorption axis of the polarizer and the stretching direction of the laminated optical film are orthogonal) The vinyl aromatic resin layer faces the polarizer side, and both are continuously pasted using the water-based adhesive obtained in Preparation Example 1, and the other side of the polarizer is protected. As a film, a saponified TAC film having a thickness of 80 μm was stuck using an adhesive made of a PVA aqueous solution having a concentration of 5% to obtain a polarizing plate (P1). When the single transmittance and polarization degree of the obtained polarizing plate were examined, they were 42.1% and 99.9%, respectively.

  In order to evaluate the characteristics of this polarizing plate, the polarizing plate and the retardation film attached to the front and back surfaces of the liquid crystal panel of Samsung Electronics Co., Ltd. (model number LN40R81BD) on the viewer side were peeled off and removed. Acrylic transparent adhesive with the negative C plate polarizing plate (P0) obtained in Production Example 2 on the back side and the polarizing plate (P1) on the front side, the same as the transmission axis of the polarizing plate originally bonded. Bonding was performed using a film. At this time, both the back surface and the front surface were bonded so that the retardation film (laminated optical film) of the polarizing plate was on the liquid crystal cell side.

  When the contrast ratio of the liquid crystal television having this polarizing plate was measured, the maximum value was 5260 and the minimum value was 110 in the range of all directions and polar angles of 0 to 80 degrees, and no unevenness was visually observed. . In the black display state, the color shift was measured at a polar angle of 0 to 60 degrees at an azimuth angle of 45 degrees, and Δu′v ′ = 0.03.

[Example 2]
<Manufacture of laminated optical film (F2)>
As a cyclic olefin-based resin (B1) and a vinyl aromatic resin (A2), Nora Chemicals Dilark D332 (styrene-maleic anhydride copolymer (maleic anhydride content 15%), Tg: 128 ° C.) was used. Others were carried out similarly to Example 1, and obtained the unstretched laminated optical film roll of the structure of B1 layer (150 micrometers) / A2 layer (120 micrometers). This laminated optical film roll was transversely stretched with a tenter at a stretching temperature of 130 ° C. and a stretching ratio of 2.0 times to obtain a laminated optical film (F2) having a thickness of 136 μm. The in-plane retardation of the obtained laminated optical film was R450 = 82 nm, R550 = 92 nm, R650 = 98 nm, and NZ = 1.72. When the adhesiveness of this laminated optical film was confirmed, the adhesiveness was good without peeling. As a result of the environmental test, the change amount of the phase difference was within ± 2% in all three conditions, and no change in the appearance was observed.

<Production of Polarizing Plate (P2) and Evaluation of Liquid Crystal Display>
A polarizing plate (P2) was obtained in the same manner as in Example 1 except that the laminated optical film (F2) was used instead of the laminated optical film (F1). When the single transmittance and polarization degree of the obtained polarizing plate were examined, they were 42.0% and 99.9%, respectively. When the contrast ratio of the liquid crystal television was measured in the same manner as in Example 1 except that the polarizing plate (P2) was used instead of the polarizing plate (P1), the maximum value was obtained in the range of all directions and polar angles of 0 to 80 degrees. : 5110, minimum value: 100, which is a high numerical value, and no unevenness was visually observed. In the black display state, when the azimuth angle was 45 degrees and the color shift was measured at a polar angle of 0 to 60 degrees, Δu′v ′ = 0.04.

<Production of Polarizing Plate (P2 ′) and Evaluation of Liquid Crystal Display>
When laminating the polarizer and the laminated optical film with a water-based adhesive, the polarizing plate (P2 ′) is the same as the polarizing plate (P2) except that the cyclic olefin-based resin layer faces the polarizer. Obtained. When the single transmittance and polarization degree of the obtained polarizing plate were examined, they were 42.0% and 99.9%, respectively. The contrast ratio of the liquid crystal television was measured in the same manner as in Example 1 except that the polarizing plate (P2 ′) was used instead of the polarizing plate (P1). Value: 5080, minimum value: 100, which is a high numerical value, and no unevenness was visually observed. In the black display state, when the azimuth angle was 45 degrees and the color shift was measured at a polar angle of 0 to 60 degrees, Δu′v ′ = 0.04.

[Example 3]
<Manufacture of laminated optical film (F3)>
The same procedure as in Example 1 was conducted except that UREX A14 (styrene-methacrylic acid copolymer, Tg: 129 ° C.) manufactured by DIC Corporation was used as the cyclic olefin resin (B1) and the vinyl aromatic resin (A3). Thus, an unstretched laminated optical film roll having a configuration of B1 layer (150 μm) / A3 layer (110 μm) was obtained. This laminated optical film roll was transversely stretched with a tenter at a stretching temperature of 130 ° C. and a stretching ratio of 2.0 times to obtain a laminated optical film (F3) having a thickness of 130 μm. The in-plane retardation of the obtained laminated optical film was R450 = 81 nm, R550 = 91 nm, R650 = 96 nm, and NZ = 1.74. When the adhesiveness of this laminated optical film was confirmed, the adhesiveness was good without peeling. As a result of the environmental test, the change amount of the phase difference was within ± 2% in all three conditions, and no change in the appearance was observed.

<Production of Polarizing Plate (P3) and Evaluation of Liquid Crystal Display>
A polarizing plate (P3) was obtained in the same manner as in Example 1 except that the laminated optical film (F3) was used instead of the laminated optical film (F1). When the single transmittance and polarization degree of the obtained polarizing plate were examined, they were 42.0% and 99.9%, respectively. When the contrast ratio of the liquid crystal television was measured in the same manner as in Example 1 except that the polarizing plate (P3) was used instead of the polarizing plate (P1), the maximum value was obtained in the range of all directions and polar angles of 0 to 80 degrees. : 5050, minimum value: 100, which is a high numerical value, and no unevenness was visually observed. In the black display state, when the azimuth angle was 45 degrees and the color shift was measured at a polar angle of 0 to 60 degrees, Δu′v ′ = 0.04.

[Example 4]
<Manufacture of laminated optical film (F4)>
An unstretched laminated optical film roll was obtained in the same manner as in Example 3 except that the laminated constitution was changed to a three-layer constitution of B1 layer (75 μm) / A3 layer (110 μm) / B1 layer (75 μm). This laminated optical film roll was transversely stretched with a tenter at a stretching temperature of 130 ° C. and a stretching ratio of 2.0 times to obtain a laminated optical film (F4) having a thickness of 130 μm. The in-plane retardation of the obtained laminated optical film was R450 = 84 nm, R550 = 93 nm, R650 = 99 nm, and NZ = 1.82. When the adhesiveness of this laminated optical film was confirmed, the adhesiveness was good without peeling. As a result of the environmental test, the change amount of the phase difference was within ± 2% in all three conditions, and no change in the appearance was observed.

<Manufacture of polarizing plate (P4) and evaluation of liquid crystal display device>
Example 1 except that the laminated optical film (F4) is used instead of the laminated optical film (F1) and the side facing the polarizer becomes a cyclic olefin resin B1 layer (necessarily for the three-layer lamination). Thus, a polarizing plate (P4) was obtained. When the single transmittance and polarization degree of the obtained polarizing plate were examined, they were 41.9% and 99.9%, respectively. When the contrast ratio of the liquid crystal television was measured in the same manner as in Example 1 except that the polarizing plate (P4) was used instead of the polarizing plate (P1), the maximum value was obtained in the range of all directions and polar angles of 0 to 80 degrees. : 4890, minimum value: 90, which is a high numerical value, and no unevenness was visually observed. In addition, when the color shift at the polar angle of 0 to 60 degrees was measured at the azimuth angle of 45 degrees in the black display state, Δu′v ′ = 0.05.

[Comparative Example 1]
<Manufacture of optical film (F6)>
A film roll (150 μm) of B1 was obtained by extruding the cyclic olefin resin (B1) alone. The film roll of B1 was transversely stretched by a tenter at a stretching temperature of 140 ° C. and a stretching ratio of 3.0 times to obtain an optical film (F6) having a thickness of 55 μm. The in-plane retardation of this optical film was R450 = 121 nm, R550 = 120 nm, R650 = 119 nm, and NZ = 1.33. As a result of the environmental test, the change amount of the phase difference was within ± 2% in all three conditions, and no change in the appearance was observed.

<Production of Polarizing Plate (P6) and Evaluation of Liquid Crystal Display>
A polarizing plate (P6) was obtained in the same manner as in Example 1 except that the optical film (F6) was used instead of the laminated optical film (F1). When the single transmittance and polarization degree of the obtained polarizing plate were examined, they were 41.8% and 99.9%, respectively. When the contrast ratio of the liquid crystal television was measured in the same manner as in Example 1 except that the polarizing plate (P6) was used instead of the polarizing plate (P1), the maximum value was obtained in the range of all directions and polar angles of 0 to 80 degrees. : 5160, minimum value: 85, high numerical value, and no unevenness was visually observed. In the black display state, the color shift at the polar angle of 0 to 60 degrees was measured at an azimuth angle of 45 degrees, and Δu′v ′ = 0.11. Since the optical film F6 does not have reverse wavelength dispersion, the Δu′v ′ value is slightly increased, and the color shift is not improved.

[Comparative Example 2]
<Manufacture of laminated optical film (F7)>
An unstretched laminated optical film roll having a constitution of B2 layer (130 μm) / A4 layer (130 μm) in the same manner as in Example 1 except that the cyclic olefin resin (B2) and the vinyl aromatic resin (A4) were used. Got. This laminated optical film roll was transversely stretched with a tenter at a stretching temperature of 130 ° C. and a stretching ratio of 2.0 times to obtain a laminated optical film (F7) having a thickness of 133 μm. The in-plane retardation of the obtained laminated optical film was R450 = 258 nm, R550 = 255 nm, R650 = 252 nm, and NZ = 1.45. When the adhesiveness of this laminated optical film was confirmed, the layers were easily separated. As a result of the environmental test, the amount of change in the phase difference exceeded 5% in the dry heat test, and the layers were separated in the wet heat test and the heat shock test.

<Manufacture of polarizing plate (P7) and evaluation of liquid crystal display device>
A polarizing plate (P7) was obtained in the same manner as in Example 1 except that the laminated optical film (F7) was used instead of the laminated optical film (F1). When the single transmittance and polarization degree of the obtained polarizing plate were examined, they were 42.0% and 99.9%, respectively. When the contrast ratio of the liquid crystal television was measured in the same manner as in Example 1 except that the polarizing plate (P7) was used instead of the polarizing plate (P1), the maximum value was obtained in the range of all directions and polar angles of 0 to 80 degrees. : 5320, minimum value: 5. In addition, when the color shift at the polar angle of 0 to 60 degrees was measured at the azimuth angle of 45 degrees in the black display state, Δu′v ′ = 0.22. The vinyl aromatic resin (A4) used for the laminated optical film (F7) has a low glass transition temperature, and when stretched, the A4 layer does not exhibit a predetermined retardation, and the laminated optical film has a desirable retardation. Therefore, the front contrast ratio is not a problem, but the contrast ratio in the oblique direction is poor and there are many color shifts.

[Comparative Example 3]
<Manufacture of laminated optical film (F8)>
A film roll (150 μm) of B1 was obtained by extruding the cyclic olefin resin (B1) alone. The film roll of B1 was transversely stretched by a tenter at a stretching temperature of 130 ° C. and a stretching ratio of 2.0 times to obtain an optical film having a thickness of 77 μm. The in-plane retardation of this optical film was R450 = 263 nm, R550 = 260 nm, R650 = 257 nm, and NZ = 1.38.

Subsequently, a polyimide solution for the alignment film is applied on the PET film with a wire bar, dried with hot air at 80 ° C. for 1 minute and further with hot air at 100 ° C. for 2 minutes, and then the surface of the polyimide alignment film is rubbed. did. A polymerizable nematic liquid crystal solution was applied onto the alignment film with a wire bar, dried at 100 ° C. for 2 minutes, and then irradiated with UV at 700 mJ / cm ² using a high pressure mercury lamp to polymerize the polymerizable nematic liquid crystal compound. When this liquid crystal cured film was peeled off from the PET film and the phase difference was measured, R450 = 174 nm, R550 = 165 nm, R650 = 159 nm, NZ = 1.02, and the thickness was 2 μm.

  The obtained liquid crystal cured film was bonded onto the optical film using an acrylic transparent adhesive film so that the optical axis directions (in-plane maximum refractive index directions) were orthogonal to each other, and the laminated optical film (F8) was laminated. Obtained. The in-plane retardation of the obtained laminated optical film was R450 = 89 nm, R550 = 95 nm, R650 = 98 nm, and NZ = 3.80. As a result of the environmental test, the maximum amount of change in the phase difference under the three conditions was 2.3%, and no change in the appearance was observed.

<Production of Polarizing Plate (P8) and Evaluation of Liquid Crystal Display>
A polarizing plate (P8) was obtained in the same manner as in Example 1 except that the laminated optical film (F8) was used in place of the laminated optical film (F1) and the liquid crystal cured layer faced the polarizer. When the single transmittance and polarization degree of the obtained polarizing plate were examined, they were 41.9% and 99.9%, respectively. The polarizing plate (P8) was used instead of the polarizing plate (P1), and the contrast ratio of the liquid crystal television was measured in the same manner as in Example 1. As a result, the maximum value was 4900 in the range of all directions and polar angles of 0 to 80 degrees. Minimum value: 15 and no unevenness was visually observed. In addition, when the color shift at the polar angle of 0 to 60 degrees was measured at the azimuth angle of 45 degrees in the black display state, Δu′v ′ = 0.15. In the F8 laminated with a liquid crystal cured film, the in-plane retardations R450, R550, and R650 have no problem because they have reverse wavelength dispersion, but the NZ coefficient is not in a desirable range due to an oblique phase difference abnormality. Therefore, although there is no problem with the front contrast ratio, the contrast ratio in the oblique direction is poor and there are many color shifts.

[Reference example]
When the retardation film previously bonded to a commercially available liquid crystal television is peeled off from the polarizing plate and an environmental test is carried out by the above method as a reference, the amount of change in retardation under the three conditions is 5% at maximum, and the test sample is I curled.

  Of the above results, Table 1 shows the evaluation results of the laminated optical film, and Table 2 shows the evaluation results of the polarizing plate and the liquid crystal display device and the panel characteristics before peeling the polarizing plate from the liquid crystal television as a reference.

［実施例５］
＜反射防止層付き偏光板（Ｐ１−１）の製造および液晶表示装置の評価＞
実施例１で用いた保護フィルムと同じＴＡＣフィルムの片面に、調製例２で作製したハードコート層塗工液をワイヤーバーで塗布し、８０℃で２分乾燥後、高圧水銀灯を用いて、６００ｍＪ／ｃｍ²でＵＶ照射し重合させ、厚さ４μｍの硬化膜を作製した。ハードコ
ート層が形成された面に、さらに調製例３で作製した低屈折率層用塗工液をワイヤーバーで塗布し、８０℃で２分乾燥後、高圧水銀灯を用いて、６００ｍＪ／ｃｍ²でＵＶ照射し
重合させ、厚さ１００ｎｍの硬化膜を形成し、反射防止層付き保護フィルムを得た。得られた保護フィルムの反射率を測定したところ２．４％以下であり、反射防止効果があることを確認した。また、Ｈａｚｅは０．５％、全光線透過率は９４．２％であった。また反射防止層の密着性は優れており、環境試験の結果、３条件とも、反射防止層に起因する外観の変化や層の剥離は見られなかった。

[Example 5]
<Manufacture of polarizing plate with antireflection layer (P1-1) and evaluation of liquid crystal display device>
The hard coat layer coating solution prepared in Preparation Example 2 was applied to one side of the same TAC film as the protective film used in Example 1 with a wire bar, dried at 80 ° C. for 2 minutes, and then 600 mJ using a high-pressure mercury lamp. The polymer was irradiated with UV at / cm ² to prepare a cured film having a thickness of 4 μm. The low-refractive-index layer coating solution prepared in Preparation Example 3 was further applied to the surface on which the hard coat layer was formed with a wire bar, dried at 80 ° C. for 2 minutes, and then 600 mJ / cm ² using a high-pressure mercury lamp. And polymerized by UV irradiation to form a cured film having a thickness of 100 nm to obtain a protective film with an antireflection layer. When the reflectance of the obtained protective film was measured, it was 2.4% or less, and it was confirmed that there was an antireflection effect. The haze was 0.5% and the total light transmittance was 94.2%. Further, the adhesion of the antireflection layer was excellent, and as a result of the environmental test, no change in appearance or peeling of the layer due to the antireflection layer was observed in all three conditions.

  In Example 1, the polarizing plate (P1-1) was obtained like Example 1 except having used the said protective film with an antireflection layer as a protective film. When the contrast ratio of the liquid crystal television was measured in the same manner as in Example 1 using the obtained polarizing plate (P1-1), the maximum value: 5210 and the minimum value: No unevenness was visually observed. In addition, when the color shift was measured at a polar angle of 0 to 60 degrees at an azimuth angle of 45 degrees in the black display state, Δu′v ′ = 0.04. In addition, there was less reflection of external light during black display.

[Example 6]
<Manufacture of polarizing plate with antiglare layer (P1-2) and evaluation of liquid crystal display device>
The antiglare layer / hard coat layer coating solution prepared in Preparation Example 4 was applied to one side of the same TAC film as the protective film used in Example 1 with a wire bar and dried at 80 ° C. for 2 minutes. Then, UV irradiation was performed at 600 mJ / cm ² for polymerization to form a cured film having a thickness of 4 μm, and a protective film with an antiglare layer was obtained. The obtained protective film had a haze of 25% and a total light transmittance of 93.0%, and the glare of outside light (fluorescent lamp) was suppressed on the surface on which the antiglare layer was formed. Further, the adhesion of the antiglare layer was excellent, and as a result of the environmental test, no change in appearance or peeling of the layer due to the antiglare layer was observed in all three conditions.

  In Example 1, the polarizing plate (P1-2) was obtained like Example 1 except having used the said protective film with a glare-proof layer as a protective film. When the contrast ratio of the liquid crystal television was measured in the same manner as in Example 1 using the obtained polarizing plate (P1-2), the maximum value was 5200 and the minimum value was within the range of all directions and polar angles of 0 to 80 degrees. No unevenness was visually observed. In the black display state, the color shift was measured at a polar angle of 0 to 60 degrees at an azimuth angle of 45 degrees, and Δu′v ′ = 0.03. In addition, the reflection and glare of external light during black display were reduced.

[Example 7]
<Manufacture of polarizing plate with antiglare layer (P1-4) and evaluation of liquid crystal display>
The laminated optical film (F1) obtained in Example 1 is made to have a roll-shaped film on one side of the polarizer obtained in Production Example 1 (stretching direction as the absorption axis of the polarizer and stretching of the laminated optical film). The vinyl aromatic resin layer was made to face the polarizer side, and both were continuously pasted using the aqueous adhesive obtained in Preparation Example 1. Further, on the other surface of the polarizer, the film roll (60 μm thickness) of the cyclic olefin resin (A1) obtained in Synthesis Example 1 was used to continuously form both using the aqueous adhesive obtained in Preparation Example 1. Affixed and the polarizing plate (P1-3) was obtained. When the single transmittance and degree of polarization of the obtained polarizing plate were examined, they were 42.3% and 99.9%, respectively.

The anti-glare layer / hard coat layer coating solution prepared in Preparation Example 4 was applied to the surface of the cyclic olefin resin film, which is a polarizer protective film of this polarizing plate, with a wire bar, dried at 80 ° C. for 2 minutes, and then high pressure Using a mercury lamp, UV irradiation was carried out at 600 mJ / cm ² for polymerization to produce a cured film having a thickness of 5 μm, and a polarizing plate (P1-4) with an antiglare layer was obtained. The glare of outside light (fluorescent lamp) was suppressed on the surface on which the antiglare layer was formed. When the protective film was peeled off from the polarizing plate and evaluated as a protective film with an antiglare layer and a hard coat layer, the haze was 30% and the total light transmittance was 93.3%. As a result of the environmental test, no change in appearance or peeling of the layer due to the antiglare layer was observed in all three conditions.

The polarizing plate (P1-4) was used instead of the polarizing plate (P1), and the contrast ratio of the liquid crystal television was measured in the same manner as in Example 1. The maximum value in the range of all directions and polar angles of 0 to 80 degrees: 5230, minimum value: 105, and no unevenness was visually observed. In the black display state, the azimuth angle is 4
When the color shift at a polar angle of 0 to 60 degrees was measured at 5 degrees, Δu′v ′ = 0.03. In addition, the reflection and glare of external light during black display were reduced.

When the antiglare layer on the surface of the polarizing plate previously bonded to the liquid crystal television was peeled off together with the protective film as the base material and subjected to an environmental test, a slight yellowing of the coating film was observed.
Table 3 shows the evaluation results of Examples 5 to 7 and the evaluation results of the polarizing plates bonded in advance to the liquid crystal television.

  The laminated optical film and polarizing plate according to the present invention can be used for various optical components. For example, various liquid crystal display devices such as liquid crystal televisions, liquid crystal monitors, mobile phones, car navigation systems, portable game machines, digital information terminals, liquid crystal projectors, electroluminescent display elements or transparent conductive films such as ITO are used for touch panels and the like. be able to. It is also useful as a near-infrared cut film used in optical systems such as wave plates and cameras used in optical systems of optical disc recording / reproducing apparatuses.

Claims (10)

A structural unit (A1) represented by the following formula (A1);
The structural unit (A2) represented by the following formula (A2) and / or the structural unit (A3) represented by the following formula (A3),
Vinyl aromatic resin (A) comprising a copolymer in which the total content of the structural unit (A2) and / or the structural unit (A3) is 5 to 40 mol% of all structural units constituting the copolymer. When,
Co-extrusion of a cyclic olefin resin (B) having a structural unit (B1) represented by the following formula (B1) and a structural unit (B2) represented by the following formula (B2) Obtaining a laminated raw film having a layer and a layer of a cyclic olefin-based resin;
A step of obtaining a laminated optical film by uniaxially stretching the obtained laminated raw film in a direction perpendicular to the longitudinal direction;
A method for producing a laminated optical film, comprising producing a laminated optical film in which the thickness ratio of the cyclic olefin-based resin layer is in the range of 50 to 90%.

(In Formula (A1), A ¹ represents a hydrogen atom or a methyl group. A ^{2 to} A ⁴ may each independently have a hydrogen atom; a halogen atom; a linking group containing oxygen, nitrogen, sulfur or silicon. A good substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms; or a polar group.)

(In Formula (A2), X is an oxygen atom or a nitrogen atom having a substituent. In Formula (A3), A ⁵ represents a hydrogen atom or a methyl group. A ⁶ represents a hydrogen atom or a carbon atom number of 1 to 30. Hydrocarbon group.)

(In formula (B1), m is an integer of 0 or more, p is an integer of 0 or more, and X is independently a group represented by the formula: —CH═CH— or a formula: —CH ₂ CH ₂ —. R ^{1 to} R ⁴ each independently represents one represented by the following (a) to (e), or represents (f) or (g).
(A) a hydrogen atom,
(B) a halogen atom,
(C) a substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms including a linking group containing an oxygen atom, a sulfur atom, a nitrogen atom or a silicon atom,
(D) a substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms,
(E) a polar group,
(F) R ¹ and R ² , or R ³ and R ⁴ represent an alkylidene group formed by bonding to each other, and R ^{1 to} R ⁴ not participating in the bonding are independent of each other from (a) to (a) to (E) represents one selected from
(G) R ¹ and R ² , R ³ and R ⁴ , or R ² and R ³ bonded together to form an aromatic ring or a non-aromatic monocyclic or polycyclic hydrocarbon ring or heterocyclic ring And R ^{1 to} R ⁴ not involved in the bond are independently selected from the above (a) to (e). )

(In formula (B2), Y is independently a group represented by the formula: —CH═CH— or a group represented by the formula: —CH ₂ CH ₂ —, and R ^{5 to} R ⁸ are each independently the following: It represents what is represented by (a) to (e), or represents (f) or (g).
(A) a hydrogen atom,
(B) a halogen atom,
(C) a substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms including a linking group containing an oxygen atom, a sulfur atom, a nitrogen atom or a silicon atom,
(D) a substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms,
(E) a polar group,
(F) R ⁵ and R ⁶ , or R ⁷ and R ⁸ represent an alkylidene group formed by bonding to each other, and R ^{5 to} R ⁸ not involved in the bonding are independent of each other from the above (a) to (a) to (E) represents one selected from
(G) R ⁵ and R ⁶ , R ⁷ and R ⁸ , or R ⁶ and R ⁷ bonded together to form an aromatic ring or a non-aromatic monocyclic or polycyclic hydrocarbon ring or heterocyclic ring R ^{5 to} R ⁸ not involved in the bond are independently selected from the above (a) to (e). ) The method for producing a laminated optical film according to claim 1, wherein the laminated optical film satisfies all of the characteristics represented by the following formulas (i) to (iv).
R450 <R550 <R650 (i)
1.0 <R650 / R550 <1.2 (ii)
70 nm ≦ R550 ≦ 150 nm (iii)
1.0 ≦ NZ ≦ 3.0 (iv)
(In the above formulas (i) to (iii), R450, R550, and R650 represent the in-plane retardation of the laminated optical film at wavelengths of 450 nm, 550 nm, and 650 nm, respectively. In the above formula (iv), NZ is NZ = (Nx−nz) / (nx−ny) is a coefficient at a wavelength of 550 nm, where nx is the maximum refractive index in the laminated optical film plane, and ny is in the laminated optical film plane. (The refractive index in the direction perpendicular to nx, nz represents the refractive index in the thickness direction of the laminated optical film perpendicular to nx and ny.) A vinyl aromatic resin layer, is a cyclic olefin-based resin layer, the manufacturing method of the laminated optical film according to claim 1 or 2, characterized in that direct contact. The glass transition temperature of the vinyl aromatic resin (A) and the glass transition temperature of the cyclic olefin resin (B) are both 110 ° C. or higher, and the difference between the two is within 20 ° C. method for producing a laminated optical film according to any one of claims 1 to 3. Laminated optical film characterized by being obtained by the process according to any one of claims 1 to 4. 6. A polarizing plate comprising the laminated optical film according to claim 5 bonded to at least one surface of a polarizer via an adhesive or a pressure-sensitive adhesive. The polarizing plate according to claim 6 , further comprising at least one layer selected from an antireflection layer and an antiglare layer. 8. The polarizing plate according to claim 6 , wherein the polarizing plate is bonded so that the maximum refractive index direction in the plane of the laminated optical film is not parallel to the transmission axis direction of the polarizer. Elliptical polarizing plate. A liquid crystal display device comprising the polarizing plate according to claim 6 . A liquid crystal display device comprising the elliptically polarizing plate according to claim 8 .