JP2019019303A - Resin composition and optical compensation film using the same - Google Patents

Abstract

To provide a resin composition suitable for an optical compensation film, and an optical compensation film excellent in phase difference characteristics using the same.SOLUTION: The resin composition comprises: a resin with a residue unit represented by general formula (1) in the figure; and a resin with positive intrinsic birefringence.SELECTED DRAWING: None

Description

  The present invention relates to a resin composition and an optical compensation film using the same, and more particularly to an optical compensation film for a liquid crystal display excellent in retardation characteristics.

  Liquid crystal displays are widely used as the most important display devices in the multimedia society, including cellular phones, computer monitors, laptop computers, and televisions. Many optical films are used in liquid crystal displays to improve display characteristics. In particular, the optical compensation film plays a major role in improving contrast and compensating for color tone when viewed from the front or obliquely.

  There are many liquid crystal displays such as vertical alignment type (VA-LCD), in-plane alignment type liquid crystal (IPS-LCD), super twist nematic type liquid crystal (STN-LCD), reflection type liquid crystal display, and transflective type liquid crystal display. There is a method, and an optical compensation film suitable for the display is required.

  As a conventional optical compensation film, a stretched film made of cellulose resin, polycarbonate, cyclic polyolefin, or the like is used. In particular, a film made of a cellulose-based resin such as a triacetyl cellulose film is widely used because it has good adhesion to polyvinyl alcohol as a polarizer.

  However, an optical compensation film made of a cellulose resin has several problems. For example, a cellulose resin film is processed into an optical compensation film having retardation values suitable for various displays by adjusting stretching conditions, but the three-dimensional film obtained by uniaxial or biaxial stretching of the cellulose resin film. In order to produce an optical compensation film having a refractive index of nx ≧ ny> nz and other three-dimensional refractive indexes, for example, a three-dimensional refractive index such as nx> nz> ny or nx = nz> ny. Requires a special stretching method such as bonding a heat-shrinkable film to one or both sides of the film, heat-stretching the laminate, and applying a shrinkage force in the thickness direction of the polymer film, and a refractive index ( It is also difficult to control the phase difference value (see, for example, Patent Documents 1 to 3).

  Here, nx represents the refractive index in the direction of the stretching axis in the film plane, ny represents the refractive index in the direction perpendicular to the stretching axis in the film plane, and nz represents the refractive index outside the film plane (thickness direction). .

  Cellulosic resin films are generally produced by a solvent casting method. Since a cellulose resin film formed by a casting method has an out-of-plane retardation (Rth) of about 40 nm in the film thickness direction, IPS mode liquid crystal There are problems such as color shift in displays. Here, the out-of-plane phase difference (Rth) is a phase difference value represented by the following equation.

Rth = [(nx + ny) / 2−nz] × d
(Where nx is the refractive index in the slow axis direction in the film plane, ny is the refractive index in the direction perpendicular to the stretching axis in the film plane, nz is the refractive index outside the film plane (thickness direction), d Indicates film thickness.)
Moreover, the retardation film which consists of a fumarate-type resin is proposed (for example, refer patent document 4).

  However, the stretched film made of a fumarate ester resin has a three-dimensional refractive index of nz> ny> nx, and an optical compensation film having a three-dimensional refractive index such as nx> nz> ny or nx = nz> ny. In order to obtain it, lamination with another optical compensation film or the like is necessary.

Japanese Patent No. 2818983 JP-A-5-297223 JP-A-5-323120 JP 2008-64817 A

  The present invention has been made in view of the above problems, and an object thereof is to provide a resin composition suitable for an optical compensation film and an optical compensation film having excellent retardation characteristics using the resin composition.

  As a result of intensive studies to solve the above problems, the present inventors have found that an optical compensation film using a specific resin composition can solve the above problems, and have completed the present invention. That is, the present invention relates to a resin composition comprising a resin having a residue unit represented by the following general formula (1) and a resin having positive intrinsic birefringence, and an optical compensation film using the resin composition Is.

（１）

(1)

(Here, R ₁ and R ₂ are each independently hydrogen (except when R ₁ and R ₂ are both hydrogen), a cyano group, an ester group (—C (═O) OX ₁ ), An amide group (—C (═O) N (X ₂ ) (X ₃ ) or —NX ₄ C (═O) X ₅ ), or an acyl group (—C (═O) X ₆ ) (where X ₁ ˜X ₆ each independently represents a linear alkyl group having 1 to 12 carbon atoms, a branched alkyl group having 1 to 12 carbon atoms, or a cyclic group having ₃ to 14 carbon atoms. R ₇ is independently hydrogen, a linear alkyl group having 1 to 12 carbon atoms, a branched alkyl group having 1 to 12 carbon atoms, a cyclic group having 3 to 14 carbon atoms, a halogen, a hydroxy group, a carboxy group, or a nitro group. Group, cyano group, thiol group, sulfonic acid group, alkoxy group (—OX ₇ ), ester group (—C (= O) OX ₈ ), sulfonyl group (—SOOX ₉ ), amide group (—C (═O) N (X ₁₀ ) (X ₁₁ ) or —NX ₁₂ C (═O) X ₁₃ ), acyl group (—C (═O) X ₁₄ ), an amino group (—N (X ₁₅ ) (X ₁₆ )), or an acyloxy group (—OC (═O) X ₁₇ ) (where X _{7 to} X ₉ are each independently A linear alkyl group having 1 to 12 carbon atoms, a branched alkyl group having 1 to 12 carbon atoms, or a cyclic group having 3 to 14 carbon atoms, and X _{10 to} X ₁₇ are each independently hydrogen, carbon number A linear alkyl group having 1 to 12, a branched alkyl group having 1 to 12 carbon atoms, or a cyclic group having 3 to 14 carbon atoms.) And R _{3 to} R ₇ are adjacent substituents. And a condensed ring structure may be formed.
The resin composition of the present invention is a resin composition comprising a resin having a residue unit represented by the general formula (1) and a resin having positive intrinsic birefringence. And since the optical compensation film using the resin composition of this invention shows a specific phase difference characteristic, it is useful as an optical compensation film for liquid crystal displays or an antireflection film.

  Hereinafter, the present invention will be described in detail.

  The resin composition of the present invention includes a resin having a residue unit represented by the general formula (1) and a resin having positive intrinsic birefringence.

In the general formula (1) of the present invention, R ₁ and R ₂ are each independently hydrogen (except when R ₁ and R ₂ are both hydrogen), a cyano group, an ester group (—C (═O ) OX ₁ ), an amide group (—C (═O) N (X ₂ ) (X ₃ ) or —NX ₄ C (═O) X ₅ ), or an acyl group (—C (═O) X ₆ ) ( Here, X _{1 to} X ₆ each independently represent a linear alkyl group having 1 to 12 carbon atoms, a branched alkyl group having 1 to 12 carbon atoms, or a cyclic group having 3 to 14 carbon atoms. Show.

Examples of the linear alkyl group having 1 to 12 carbon atoms in X _{1 to} X ₆ include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group, and an n-hexyl group. Examples of the branched alkyl group having 1 to 12 carbon atoms include isopropyl group, sec-butyl group, tert-butyl group, isobutyl group and the like, and examples of the cyclic group having 3 to 14 carbon atoms include: A cyclopropyl group, a cyclobutyl group, a cyclohexyl group, a phenyl group, a naphthyl group, etc. are mentioned.

As R ₁ and R ₂ in the general formula (1) of the present invention, one of them is a cyano group because it is more excellent in retardation characteristics and transparency, methyl ester group, ethyl ester group, n-propyl ester group, isopropyl Ester groups such as ester groups, n-butyl ester groups, sec-butyl ester groups, isobutyl ester groups, tert-butyl ester groups; amide groups such as dimethylamide groups, diethylamide groups, di-n-propylamide groups, diisopropylamide groups Selected from the group consisting of acyl groups such as acetyl group, propionyl group, benzoyl group, etc., preferably the other is hydrogen or cyano group, any one of which consists of cyano group, ester group, amide group, acyl group; More preferably, the other is a cyano group, and either one is An anode group or an ester group, and particularly preferably the other is a cyano group.

R _{3 to} R ₇ in the general formula (1) of the present invention are each independently hydrogen, a linear alkyl group having 1 to 12 carbon atoms, a branched alkyl group having 1 to 12 carbon atoms, or 3 to 14 carbon atoms. Cyclic group, halogen, hydroxy group, carboxy group, nitro group, cyano group, thiol group, sulfonic acid group, alkoxy group (—OX ₇ ), ester group (—C (═O) OX ₈ ), sulfonyl group (—SOOX) ₉ ), an amide group (—C (═O) N (X ₁₀ ) (X ₁₁ ) or —NX ₁₂ C (═O) X ₁₃ ), an acyl group (—C (═O) X ₁₄ ), an amino group ( —N (X ₁₅ ) (X ₁₆ )) or an acyloxy group (—OC (═O) X ₁₇ ) (where X _{7 to} X ₉ are each independently a linear alkyl having 1 to 12 carbon atoms) Group, a branched alkyl group having 1 to 12 carbon atoms, or 3 to 1 carbon atoms 4 represents a cyclic group, and X _{10 to} X ₁₇ each independently represent hydrogen, a linear alkyl group having 1 to 12 carbon atoms, a branched alkyl group having 1 to 12 carbon atoms, or a cyclic group having 3 to 14 carbon atoms. Group). R _{3 to} R ₇ may form a condensed ring structure with adjacent substituents.

Examples of the linear alkyl group having 1 to 12 carbon atoms in R _{3 to} R ₇ include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group, and an n-hexyl group. Examples of the branched alkyl group having 1 to 12 carbon atoms include isopropyl group, isobutyl group, sec-butyl group, tert-butyl group and the like, and examples of the cyclic group having 3 to 14 carbon atoms include: A cyclopropyl group, a cyclobutyl group, a cyclohexyl group, a phenyl group, a naphthyl group, etc. are mentioned.

Examples of the halogen in R _{3 to} R ₇ include fluorine, chlorine, bromine and the like.

Examples of the linear alkyl group having 1 to 12 carbon atoms in X _{7 to} X ₁₇ include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group, and an n-hexyl group. Examples of the branched alkyl group having 1 to 12 carbon atoms include isopropyl group, isobutyl group, sec-butyl group, tert-butyl group and the like, and examples of the cyclic group having 3 to 14 carbon atoms include: A cyclopropyl group, a cyclobutyl group, a cyclohexyl group, a phenyl group, a naphthyl group, etc. are mentioned.

R _{3 to} R ₇ in the general formula (1) of the present invention are excellent in retardation characteristics and transparency, and thus are methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl. Group, tert-butyl group, isobutyl group, cyclohexyl group, fluorine atom, chlorine atom, bromine atom, hydroxy group, carboxy group, nitro group, cyano group, thiol group, sulfonic acid group, methoxy group, ethoxy group, n-propoxy Group, isopropoxy group, methyl ester group, ethyl ester group, n-propyl ester group, isopropyl ester group, methylsulfonyl group, ethylsulfonyl group, n-propylsulfonyl group, isopropylsulfonyl group, amide group, dimethylamide group, diethylamide Group, di-n-propylamide group, diisopropylamide group, Rumyl group, acetyl group, propionyl group, butyryl group, isobutyryl group, amino group, dimethylamino group, diethylamino group, di-n-propylamino group, diisopropylamino group, formyloxy group, acetyloxy group, propionyloxy group are preferred, Hydroxy group, carboxy group, thiol group, sulfonic acid group, methyl ester group, ethyl ester group, n-propyl ester group, isopropyl ester group, methylsulfonyl group, ethylsulfonyl group, n-propylsulfonyl group, isopropylsulfonyl group, amide Group, dimethylamide group, diethylamide group, di-n-propylamide group, diisopropylamide group, formyl group, acetyl group, propionyl group, butyryl group, isobutyryl group, amino group, dimethylamino group, diethylamino group Di n- propylamino group, diisopropylamino group, formyloxy group, acetyloxy group, propionyloxy group preferably a hydroxy group, a carboxy group more preferred.

In the present invention, any one of R ₁ and R ₂ is selected from the group consisting of a cyano group, an ester group, an amide group, and an acyl group, the other is a cyano group, and R _{3 to} R ₇ 1 or more types of hydrogen bond substitution by which at least 1 or more is selected from the group which consists of a hydroxy group, a carboxy group, a thiol group, a sulfonic acid group, an ester group, an amide group, an acyl group, an amino group, a sulfonyl group, and an acyloxy group Particularly preferred is a group.

Specific examples of the residue unit represented by the general formula (1) include α-cyanocinnamate methyl residue unit, 2-hydroxy-α-cyanocinnamate methyl residue unit, and 3-hydroxy-α-. Cyanocinnamate methyl residue units, 4-hydroxy-α-cyanocinnamate methyl residue units, 2,3-dihydroxy-α-cyanocinnamate methyl residue units, 3,4-dihydroxy-α-cyanocinnamate methyl units Residue unit, 2-carboxy-α-cyanocinnamate methyl residue unit, 3-carboxy-α-cyanocinnamate methyl residue unit, 4-carboxy-α-cyanocinnamate methyl residue unit, 2,3- Dicarboxy-α-cyanocinnamic acid methyl residue unit, 3,4-dicarboxy-α-cyanocinnamic acid methyl residue unit, 2-carboxy-3-hydroxy-α-cyanocinnamic acid methyl residue unit Position, 3-carboxy-2-hydroxy-α-cyanocinnamate methyl residue unit, 3-carboxy-4-hydroxy-α-cyanocinnamate methyl residue unit, 4-carboxy-3-hydroxy-α-cyanocinnamate Acid methyl residue unit, 2-sulfanyl-α-cyanocinnamic acid methyl residue unit, 3-sulfanyl-α-cyanocinnamic acid methyl residue unit, 4-sulfanyl-α-cyanocinnamic acid methyl residue unit, 2- Sulfonic acid-α-cyanocinnamic acid methyl residue unit, 3-sulfonic acid-α-cyanocinnamic acid methyl residue unit, 4-sulfonic acid-α-cyanocinnamic acid methyl residue unit, 2-methoxycarbonyl-α- Cyanocinnamate methyl residue units, 3-methoxycarbonyl-α-cyanocinnamate methyl residue units, 4-methoxycarbonyl-α-cyanocinnamate methyl units Group unit, 2-ethoxycarbonyl-α-cyanocinnamic acid methyl residue unit, 3-ethoxycarbonyl-α-cyanocinnamic acid methyl residue unit, 4-ethoxycarbonyl-α-cyanocinnamic acid methyl residue unit, 2- Formyl-α-cyanocinnamic acid methyl residue units, 3-formyl-α-cyanocinnamic acid methyl residue units, 4-formyl-α-cyanocinnamic acid methyl residue units, 2-acetyl-α-cyanocinnamic acid methyl units Residue unit, 3-acetyl-α-cyanocinnamate methyl residue unit, 4-acetyl-α-cyanocinnamate methyl residue unit, 2-amino-α-cyanocinnamate methyl residue unit, 3-amino- α-cyanocinnamate methyl residue unit, 4-amino-α-cyanocinnamate methyl residue unit, 2-methylsulfonyl-α-cyanocinnamate methyl residue unit, 3-methyl Sulfonyl-α-cyanocinnamate methyl residue unit, 4-methylsulfonyl-α-cyanocinnamate methyl residue unit, α-cyanocyanocinnamate residue unit, 2-hydroxy-α-cyanocinnamate ethyl residue unit 3-hydroxy-α-cyanocinnamic acid ethyl residue unit, 4-hydroxy-α-cyanocyanocinnamic acid residue unit, 2,3-dihydroxy-α-cyanocinnamic acid ethyl residue unit, 3,4-dihydroxy -Α-ethyl cyanocinnamate residue unit, 2-carboxy-α-cyanocinnamic acid ethyl residue unit, 3-carboxy-α-cyanocinnamic acid ethyl residue unit, 4-carboxy-α-cyanocinnamic acid ethyl residue Group unit, 2,3-dicarboxy-α-cyanocyanocinnamate residue unit, 3,4-dicarboxy-α-cyanocinnamate ethyl residue unit, 2-carboxy- 3-hydroxy-α-cyanocyanocinnamic acid residue units, 3-carboxy-2-hydroxy-α-cyanocyanocinnamic acid residue units, 3-carboxy-4-hydroxy-α-cyanocinnamic acid ethyl residue units, 4-carboxy-3-hydroxy-α-cyanocyanocinnamic acid residue units, 2-carboxy-4-hydroxy-α-cyanocinnamic acid ethyl residue units, 4-carboxy-2-hydroxy-α-cyanocinnamic acid ethyl units Residue unit, 2-sulfanyl-α-cyanocinnamic acid ethyl residue unit, 3-sulfanyl-α-cyanocinnamic acid ethyl residue unit, 4-sulfanyl-α-cyanocinnamic acid ethyl residue unit, 2-sulfonic acid -Ethyl α-cyanocinnamate residue unit, 3-sulfonic acid-ethyl α-cyanocinnamate residue unit, 4-sulfonic acid-α-cyanocinnamic acid ethyl ester Residue unit, 2-methoxycarbonyl-α-cyanocinnamic acid ethyl residue unit, 3-methoxycarbonyl-α-cyanocinnamic acid ethyl residue unit, 4-methoxycarbonyl-α-cyanocinnamic acid ethyl residue unit, 2 -Ethoxycarbonyl-α-cyanocinnamic acid ethyl residue unit, 3-ethoxycarbonyl-α-cyanocinnamic acid ethyl residue unit, 4-ethoxycarbonyl-α-cyanocinnamic acid ethyl residue unit, 2-formyl-α- Ethyl cyanocinnamate residue units, 3-formyl-α-ethyl cyanocinnamate residue units, 4-formyl-α-ethyl cyanocinnamate residue units, 2-acetyl-α-cyanoethyl cinnamate residue units, 3-acetyl-α-cyanocinnamic acid ethyl residue unit, 4-acetyl-α-cyanocinnamic acid ethyl residue unit, 2-amino-α-cyanocinnamic leather unit Ethyl residue unit, 3-amino-α-cyanocinnamic acid ethyl residue unit, 4-amino-α-cyanocinnamic acid ethyl residue unit, 2-methylsulfonyl-α-cyanocinnamic acid ethyl residue unit, 3 -Methylsulfonyl-α-cyanocinnamic acid ethyl residue unit, 4-methylsulfonyl-α-cyanocinnamic acid ethyl residue unit, α-cyanocinnamic acid n-propyl residue unit, 2-hydroxy-α-cyanocinnamic acid unit n-propyl residue unit, 3-hydroxy-α-cyanocinnamic acid n-propyl residue unit, 4-hydroxy-α-cyanocinnamic acid n-propyl residue unit, 2,3-dihydroxy-α-cyanocinnamic acid n-propyl residue unit, 3,4-dihydroxy-α-cyanocinnamic acid n-propyl residue unit, 2-carboxy-α-cyanocinnamic acid n-propyl residue unit, 3-cal Xyl-α-cyanocinnamic acid n-propyl residue unit, 4-carboxy-α-cyanocinnamic acid n-propyl residue unit, 2,3-dicarboxy-α-cyanocinnamic acid n-propyl residue unit, 3 , 4-Dicarboxy-α-cyanocinnamic acid n-propyl residue unit, 2-carboxy-3-hydroxy-α-cyanocinnamic acid n-propyl residue unit, 3-carboxy-2-hydroxy-α-cyanocinnamic acid unit Acid n-propyl residue unit, 3-carboxy-4-hydroxy-α-cyanocinnamic acid n-propyl residue unit, 4-carboxy-3-hydroxy-α-cyanocinnamic acid n-propyl residue unit, 2- Carboxy-4-hydroxy-α-cyanocinnamic acid n-propyl residue unit, 4-carboxy-2-hydroxy-α-cyanocinnamic acid n-propyl residue unit, 2-sulfani Ru-α-cyanocinnamic acid n-propyl residue unit, 3-sulfanyl-α-cyanocinnamic acid n-propyl residue unit, 4-sulfanyl-α-cyanocinnamic acid n-propyl residue unit, 2-sulfonic acid -Α-cyanocinnamic acid n-propyl residue unit, 3-sulfonic acid-α-cyanocinnamic acid n-propyl residue unit, 4-sulfonic acid-α-cyanocinnamic acid n-propyl residue unit, 2-methoxy Carbonyl-α-cyanocinnamic acid n-propyl residue unit, 3-methoxycarbonyl-α-cyanocinnamic acid n-propyl residue unit, 4-methoxycarbonyl-α-cyanocinnamic acid n-propyl residue unit, 2- Ethoxycarbonyl-α-cyanocinnamic acid n-propyl residue unit, 3-ethoxycarbonyl-α-cyanocinnamic acid n-propyl residue unit, 4-ethoxycarbonyl-α Cyanocinnamate n-propyl residue unit, 2-formyl-α-cyanocinnamic acid n-propyl residue unit, 3-formyl-α-cyanocinnamic acid n-propyl residue unit, 4-formyl-α-cyanocinnamic unit Acid n-propyl residue unit, 2-acetyl-α-cyanocinnamic acid n-propyl residue unit, 3-acetyl-α-cyanocinnamic acid n-propyl residue unit, 4-acetyl-α-cyanocinnamic acid n -Propyl residue unit, 2-amino-α-cyanocinnamic acid n-propyl residue unit, 3-amino-α-cyanocinnamic acid n-propyl residue unit, 4-amino-α-cyanocinnamic acid n-propyl Residue unit, 2-methylsulfonyl-α-cyanocinnamic acid n-propyl residue unit, 3-methylsulfonyl-α-cyanocinnamic acid n-propyl residue unit, 4-methylsulfonyl-α-cyano N-propyl cinnamate residue unit, isopropyl residue of α-cyanocinnamic acid residue unit, 2-hydroxy-α-cyanocinnamic acid isopropyl residue unit, 3-hydroxy-α-cyanocinnamic acid isopropyl residue unit, 4- Hydroxy-α-cyanocinnamic acid isopropyl residue unit, 2,3-dihydroxy-α-cyanocinnamic acid isopropyl residue unit, 3,4-dihydroxy-α-cyanocinnamic acid isopropyl residue unit, 2-carboxy-α- Isopropyl cyanocinnamate residue unit, 3-carboxy-α-cyanocinnamate isopropyl residue unit, 4-carboxy-α-cyanocinnamate isopropyl residue unit, 2,3-dicarboxy-α-cyanocinnamate isopropyl residue Group unit, 3,4-dicarboxy-α-cyanocinnamate isopropyl residue unit, 2-carboxy-3- Droxy-α-cyanocinnamic acid isopropyl residue unit, 3-carboxy-2-hydroxy-α-cyanocinnamic acid isopropyl residue unit, 3-carboxy-4-hydroxy-α-cyanocinnamic acid isopropyl residue unit, 4- Carboxy-3-hydroxy-α-cyanocinnamic acid isopropyl residue unit, 2-carboxy-4-hydroxy-α-cyanocinnamic acid isopropyl residue unit, 4-carboxy-2-hydroxy-α-cyanocinnamic acid isopropyl residue unit Unit, α-cyanocinnamic acid n-butyl residue unit, 2-hydroxy-α-cyanocinnamic acid n-butyl residue unit, 3-hydroxy-α-cyanocinnamic acid n-butyl residue unit, 4-hydroxy- α-cyanocinnamic acid n-butyl residue unit, 2,3-dihydroxy-α-cyanocinnamic acid n-butyl residue unit, 3 4-dihydroxy-α-cyanocinnamic acid n-butyl residue unit, 2-carboxy-α-cyanocinnamic acid n-butyl residue unit, 3-carboxy-α-cyanocinnamic acid n-butyl residue unit, 4- Carboxy-α-cyanocinnamic acid n-butyl residue unit, 2,3-dicarboxy-α-cyanocinnamic acid n-butyl residue unit, 3,4-dicarboxy-α-cyanocinnamic acid n-butyl residue unit Unit, 2-carboxy-3-hydroxy-α-cyanocinnamic acid n-butyl residue unit, 3-carboxy-2-hydroxy-α-cyanocinnamic acid n-butyl residue unit, 3-carboxy-4-hydroxy- α-cyanocinnamic acid n-butyl residue unit, 4-carboxy-3-hydroxy-α-cyanocinnamic acid n-butyl residue unit, α-cyanocinnamic acid isobutyl residue unit, 2-hydroxy-α -Cyanocinnamate isobutyl residue unit, 3-hydroxy-α-cyanocinnamic acid isobutyl residue unit, 4-hydroxy-α-cyanocinnamic acid isobutyl residue unit, 2,3-dihydroxy-α-cyanocinnamic acid isobutyl residue Group unit, 3,4-dihydroxy-α-cyanocinnamic acid isobutyl residue unit, 2-carboxy-α-cyanocinnamic acid isobutyl residue unit, 3-carboxy-α-cyanocinnamic acid isobutyl residue unit, 4-carboxy -Α-cyanocinnamic acid isobutyl residue unit, 2,3-dicarboxy-α-cyanocinnamic acid isobutyl residue unit, 3,4-dicarboxy-α-cyanocinnamic acid isobutyl residue unit, 2-carboxy-3 -Hydroxy-α-cyanocinnamic acid isobutyl residue unit, 3-carboxy-2-hydroxy-α-cyanocinnamic acid isobutyric acid Residue unit, 3-carboxy-4-hydroxy-α-cyanocinnamic acid isobutyl residue unit, 4-carboxy-3-hydroxy-α-cyanocinnamic acid isobutyl residue unit, 2-carboxy-4-hydroxy-α -Cyanocinnamate isobutyl residue unit, 4-carboxy-2-hydroxy-α-cyanocinnamic acid isobutyl residue unit, benzalmalononitrile residue unit, 2-hydroxybenzalmalononitrile residue unit, 3-hydroxyben Zalmalononitrile residue unit, 4-hydroxybenzalmalononitrile residue unit, 2,3-dihydroxybenzalmalononitrile residue unit, 3,4-dihydroxybenzalmalononitrile residue unit, 2-carboxybenzalmalono Nitrile residue unit, 3-carboxybenzalmalononitrile residue unit, 4-carbo Cybenzalmalononitrile residue unit, 2,3-dicarboxybenzalmalononitrile residue unit, 3,4-dicarboxybenzalmalononitrile residue unit, 2-carboxy-3-hydroxy-benzalmalononitrile residue Group unit, 3-carboxy-2-hydroxy-benzalmalononitrile residue unit, 3-carboxy-4-hydroxy-benzalmalononitrile residue unit, 4-carboxy-3-hydroxy-benzalmalononitrile residue unit 2-sulfanyl-benzalmalononitrile residue unit, 3-sulfanylbenzalmalononitrile residue unit, 4-sulfanylbenzalmalononitrile residue unit, 2-sulfonic acid benzalmalononitrile residue unit, 3-sulfone Acid benzalmalononitrile residue unit, 4-sulfonic acid benzalmalononitrile Residue unit, 2-methoxycarbonylbenzalmalononitrile residue unit, 3-methoxycarbonylbenzalmalononitrile residue unit, 4-methoxycarbonylbenzalmalononitrile residue unit, 2-ethoxycarbonylbenzalmalononitrile residue Group unit, 3-ethoxycarbonylbenzalmalononitrile residue unit, 4-ethoxycarbonylbenzalmalononitrile residue unit, 2-formylbenzalmalononitrile residue unit, 3-formylbenzalmalononitrile residue unit, 4 -Formylbenzalmalononitrile residue unit, 2-acetylbenzalmalononitrile residue unit, 3-acetylbenzalmalononitrile residue unit, 4-acetylbenzalmalononitrile residue unit, 2-aminobenzalmalononitrile residue unit Residue unit, 3-aminobenzalmalono Tolyl residue unit, 4-aminobenzalmalononitrile residue unit, 2-methylsulfonylbenzalmalononitrile residue unit, 3-methylsulfonylbenzalmalononitrile residue unit, 4-methylsulfonylbenzalmalononitrile residue Units, cinnamonitrile residue units, 2-hydroxycinnamonitrile residue units, 3-hydroxycinnamonitrile residue units, 4-hydroxycinnamonitrile residue units, 2,3-dihydroxycinnamonitrile residue units 3,4-dihydroxycinnamonitrile residue unit, 2-carboxycinnamonitrile residue unit, 3-carboxycinnamonitrile residue unit, 4-carboxycinnamonitrile residue unit, 2,3-dicarboxycin A nitronitrile residue unit, a 3,4-dicarboxycinnamonitrile residue unit, -Carboxycinnamonitrile residue unit, 3-carboxy-2-hydroxy-cinnamonitrile residue unit, 3-carboxy-4-hydroxy-cinnamonitrile residue unit, 4-carboxy-3-hydroxy-cinnamonitrile Residue unit, 2-carboxy-4-hydroxy-cinnamonitrile residue unit, 4-carboxy-3-hydroxy-cinnamonitrile residue unit, chalcone residue unit, 2-hydroxychalcone residue unit, 4-hydroxy Chalcone residue unit, 4-hydroxychalcone residue unit, 2,3-dihydroxychalcone residue unit, 3,4-dihydroxychalcone residue unit, 2-carboxychalcone residue unit, 3-carboxychalcone residue unit, 4 -Carboxychalcone residue unit, 2,3-dicarboxychalcone residue unit, 3,4-dicar Boxychalcone residue unit, 2-carboxychalcone residue unit, 3-carboxy-2-hydroxy-chalcone residue unit, 3-carboxy-4-hydroxy-chalcone residue unit, 4-carboxy-3-hydroxy-chalcone residue One or more selected from the group consisting of a unit, a 2-carboxy-4-hydroxy-chalcone residue unit, and a 4-carboxy-2-hydroxy-chalcone residue unit may be mentioned.

  As the residue unit represented by the general formula (1), 2-hydroxy-α-cyanocinnamic acid ester residue unit and 3-hydroxy-α-cyanocinnamic acid ester are excellent because of the retardation property and transparency. Residue unit, 4-hydroxy-α-cyanocinnamic acid ester residue unit, 2,3-dihydroxy-α-cyanocinnamic acid ester residue unit, 2,4-dihydroxy-α-cyanocinnamic acid ester residue unit, 3,4-dihydroxy-α-cyanocinnamic acid ester residue unit, 2-carboxy-α-cyanocinnamic acid ester residue unit, 3-carboxy-α-cyanocinnamic acid ester residue unit, 4-carboxy-α- Cyanocinnamate residue units, 2,3-dicarboxy-α-cyanocinnamic acid ester residue units, 2,4-dicarboxy-α-cyanocinnamic acid ester Residue unit, 3,4-dicarboxy-α-cyanocinnamic acid ester residue unit, 2-carboxy-3-hydroxy-α-cyanocinnamic acid ester residue unit, 3-carboxy-2-hydroxy-α- Cyanocinnamate residue units, 3-carboxy-4-hydroxy-α-cyanocinnamate residue units, 4-carboxy-3-hydroxy-α-cyanocinnamate residue units, 2-hydroxybenzalmalono Nitrile residue unit, 3-hydroxybenzalmalononitrile residue unit, 4-hydroxybenzalmalononitrile residue unit, 2,3-dihydroxybenzalmalononitrile residue unit, 2,4-dihydroxybenzalmalononitrile residue Base unit, 3,4-dihydroxybenzalmalononitrile residue unit, 2-carboxybenzalmalonontri Residue unit, 3-carboxybenzalmalononitrile residue unit, 4-carboxybenzalmalononitrile residue unit, 2,3-dicarboxybenzalmalononitrile residue unit, 2,4-dicarboxybenzalmalono Nitrile residue unit, 3,4-dicarboxybenzalmalononitrile residue unit, 2-carboxy-3-hydroxy-benzalmalononitrile residue unit, 3-carboxy-2-hydroxy-benzalmalononitrile residue unit 1 or more types selected from the group which consists of 3-carboxy-4-hydroxy-benzalmalononitrile residue unit and 4-carboxy-3-hydroxy-benzalmalononitrile residue unit are preferable.

  The resin having a residue unit represented by the general formula (1) of the present invention preferably further has a residue unit represented by the following general formula (2) or a residue unit represented by the following general formula (3). .

（２）

(2)

(Here, R ₈ represents hydrogen, a linear alkyl group having 1 to 12 carbon atoms, a branched alkyl group having 1 to 12 carbon atoms, or a cyclic group having 3 to 14 carbon atoms, and R ₉ represents hydrogen or a carboxy group. Or an ester group (—C (═O) OX ₁₈ ), wherein R _{10 to} R ₁₄ are each independently hydrogen, a linear alkyl group having 1 to 12 carbon atoms, or a branched alkyl group having 1 to 12 carbon atoms. , C 3-14 cyclic group, halogen, hydroxy group, carboxy group, nitro group, cyano group, thiol group, sulfonic acid group, alkoxy group (—OX ₁₉ ), ester group (—C (═O) OX ₂₀ ), Sulfonyl group (—SOOX ₂₁ ), amide group (—C (═O) N (X ₂₂ ) (X ₂₃ ) or —NX ₂₄ C (═O) X ₂₅ ), acyl group (—C (═O) X _26), an amino group _{(-N (X 27) (X} 2 )), Or an acyloxy group _{(-OC (= O) X 29} ) ( _wherein, X 18 _{to X 21} are each independently a linear alkyl group having 1 to 12 carbon atoms, branched having 1 to 12 carbon atoms An alkyl group or a cyclic group having 3 to 14 carbon atoms, wherein X _{22 to} X ₂₉ are each independently hydrogen, a linear alkyl group having 1 to 12 carbon atoms, or a branched alkyl group having 1 to 12 carbon atoms. Or a cyclic group having 3 to 14 carbon atoms.) And R _{10 to} R ₁₄ may form a condensed ring structure with adjacent substituents.

（３）

(3)

(Here, R ₁₅ represents an m-membered ring heterocyclic residue containing one or more heteroatoms or a 5-membered ring residue containing no heteroatoms, and m represents an integer of 5 to 10. The ring residue and the 5-membered ring residue may form a condensed ring structure.)
Examples of the linear alkyl group having 1 to 12 carbon atoms in R ₈ and R _{10 to} R ₁₄ include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group, and an n-hexyl group. Examples of the branched alkyl group having 1 to 12 carbon atoms include isopropyl group, isobutyl group, sec-butyl group, tert-butyl group and the like, and examples of the cyclic group having 3 to 14 carbon atoms include Examples thereof include a cyclopropyl group, a cyclobutyl group, a cyclohexyl group, a phenyl group, and a naphthyl group.

Examples of the halogen in R _{10 to} R ₁₄ include fluorine, chlorine, bromine and the like.

Examples of the linear alkyl group having 1 to 12 carbon atoms in X ₁₈ to X _29, for example, mentioned a methyl group, an ethyl group, n- propyl group, n- butyl group, n- pentyl group, n- hexyl and the like Examples of the branched alkyl group having 1 to 12 carbon atoms include isopropyl group, isobutyl group, sec-butyl group, tert-butyl group and the like, and examples of the cyclic group having 3 to 14 carbon atoms include: A cyclopropyl group, a cyclobutyl group, a cyclohexyl group, a phenyl group, a naphthyl group, etc. are mentioned.

Examples of the hetero atom in R ₁₅ include an oxygen atom, a nitrogen atom, and a sulfur atom.

  Examples of the residue unit represented by the general formula (2) include styrene residues such as a styrene residue unit, an α-methylstyrene residue unit, a p-hydroxystyrene residue unit, and a p-carboxystyrene residue unit. Unit: vinylnaphthalene residue unit such as 2-vinylnaphthalene residue; cinnamic acid residue unit; silicic acid methyl residue unit, ethyl cinnamate residue unit, cinnamate isopropyl residue unit, etc. Examples thereof include cinnamate residue units and the like, and substituents thereof.

  Examples of the residue unit represented by formula (3) include vinylpyrrole residue units such as 1-vinylpyrrole residue units; 1-vinylindole residue units; 9-vinylcarbazole residue units; Vinylquinoline residue units such as vinylquinoline residue units; 1-vinylisoquinoline residue units; vinylpyridine residue units such as 2-vinylpyridine residue units; vinylimidazoles such as 1-vinylimidazole residue units 5-vinyl-2-pyrazolin residue unit; 2-vinylpyrazine residue unit; vinyl-s-triazine residue unit; 10-vinyl-9-hydroacridine residue unit; 1-vinyltetrazole residue Vinyltetrazole residue units; N-vinylpyrrolidone residue units; N-vinyl-ε-caprolactam residue units; N-vinylsuccin N-vinylphthalimide residue unit; N-vinylsaccharin residue unit; vinylfuran residue unit such as 2-vinylfuran residue unit; 2-vinylbenzofuran residue unit; 2-vinylthiophene residue Vinylthiophene residue units such as group units; 2-vinylbenzoxazole residue units; N-vinyloxazolidone residue units; 2-vinylthiazole residue units; 2-vinylbenzothiazole residue units and their substituent additions Thing etc. are mentioned.

  Among the residue unit represented by the general formula (2) and the residue unit represented by the general formula (3), the styrene residue unit, α-methylstyrene, p-hydroxy are excellent because of their retardation characteristics and transparency. Styrene residue units such as styrene residue units and p-carboxystyrene residue units; Vinylnaphthalene residue units such as 2-vinylnaphthalene residues; 1-vinylindole residue units; 9-vinylcarbazole residue units N-vinylsuccinimide residue unit; N-vinylphthalimide residue unit; vinylfuran residue unit such as 2-vinylfuran residue unit; 2-vinylbenzofuran residue unit; cinnamic acid residue unit; Cinnamic acid ester residue units such as methyl acrylate residue units, ethyl cinnamate residue units, and isopropyl cinnamate residue units, etc., and their substituent addition products are preferred. Styrene residue unit, 1-vinylnaphthalene residue unit, 2-vinylnaphthalene residue unit, 1-vinylindole residue unit, 9-vinylcarbazole residue unit, N-vinylsuccinimide residue unit, N-vinylphthalimide Residual unit, 2-vinylfuran residue unit, 2-vinylbenzofuran residue unit (these residue units may be selected from the group consisting of hydrogen on the cyclic group optionally substituted with any substituent). One or more selected from the above are more preferable.

  As a resin having a residue unit represented by the general formula (1), since a film having excellent optical properties can be obtained, a 4-hydroxy-α-cyanocinnamic acid ester-2-vinylnaphthalene copolymer, 4 -Hydroxy-α-cyanocinnamic acid ester-1-vinylindole copolymer, 4-hydroxy-α-cyanocinnamic acid ester-9-vinylcarbazole copolymer, 4-hydroxy-α-cyanocinnamic acid ester-N- Vinylsuccinimide copolymer, 4-hydroxy-α-cyanocinnamic acid ester-N-vinylphthalimide copolymer, 4-hydroxy-α-cyanocinnamic acid ester-2-vinylfuran copolymer, 4-hydroxy-α- Cyanocinnamate-2-vinylbenzofuran copolymer, 2,3-dihydroxy-α-cyanocinnamate Styrene copolymer, 2,3-dihydroxy-α-cyanocinnamic acid ester-2-vinylnaphthalene copolymer, 2,3-dihydroxy-α-cyanocinnamic acid ester-1-vinylindole copolymer, 2, 3-dihydroxy-α-cyanocinnamic acid ester-9-vinylcarbazole copolymer, 2,3-dihydroxy-α-cyanocinnamic acid ester-N-vinylsuccinimide copolymer, 2,3-dihydroxy-α-cyanocinnamic leather Acid ester-N-vinylphthalimide copolymer, 2,3-dihydroxy-α-cyanocinnamic acid ester-2-vinylfuran copolymer, 2,3-dihydroxy-α-cyanocinnamic acid ester-2-vinylbenzofuran copolymer Polymer, 2,4-dihydroxy-α-cyanocinnamic acid ester-styrene copolymer, 2,4-dihydroxy Si-α-cyanocinnamic acid ester-2-vinylnaphthalene copolymer, 2,4-dihydroxy-α-cyanocinnamic acid ester-1-vinylindole copolymer, 2,4-dihydroxy-α-cyanocinnamic acid ester -9-vinylcarbazole copolymer, 2,4-dihydroxy-α-cyanocinnamic acid ester-N-vinylsuccinimide copolymer, 2,4-dihydroxy-α-cyanocinnamic acid ester-N-vinylphthalimide copolymer 2,4-dihydroxy-α-cyanocinnamic acid ester-2-vinylfuran copolymer, 2,4-dihydroxy-α-cyanocinnamic acid ester-2-vinylbenzofuran copolymer, 3,4-dihydroxy-α -Cyanocinnamate-styrene copolymer, 3,4-dihydroxy-α-cyanocinnamate-2-bi Lunaphthalene copolymer, 3,4-dihydroxy-α-cyanocinnamic acid ester-1-vinylindole copolymer, 3,4-dihydroxy-α-cyanocinnamic acid ester-9-vinylcarbazole copolymer, 3, 4-dihydroxy-α-cyanocinnamic acid ester-N-vinylsuccinimide copolymer, 3,4-dihydroxy-α-cyanocinnamic acid ester-N-vinylphthalimide copolymer, 3,4-dihydroxy-α-cyanocinnamic leather Acid ester-2-vinylfuran copolymer, 3,4-dihydroxy-α-cyanocinnamic acid ester-2-vinylbenzofuran copolymer, 4-carboxy-α-cyanocinnamic acid ester-styrene copolymer, 4- Carboxy-α-cyanocinnamic acid ester-2-vinylnaphthalene copolymer, 4-carboxy-α-cyano Cinnamic acid ester-1-vinylindole copolymer, 4-carboxy-α-cyanocinnamic acid ester-9-vinylcarbazole copolymer, 4-carboxy-α-cyanocinnamic acid ester-N-vinylsuccinimide copolymer 4-carboxy-α-cyanocinnamic acid ester-N-vinylphthalimide copolymer, 4-carboxy-α-cyanocinnamic acid ester-2-vinylfuran copolymer, 4-carboxy-α-cyanocinnamic acid ester- 2-vinylbenzofuran copolymer, 2,3-dicarboxy-α-cyanocinnamic acid ester-styrene copolymer, 2,3-dicarboxy-α-cyanocinnamic acid ester-2-vinylnaphthalene copolymer, 2 , 3-Dicarboxy-α-cyanocinnamic acid ester-1-vinylindole copolymer, 2,3-dicarboxy α-cyanocinnamic acid ester-9-vinylcarbazole copolymer, 2,3-dicarboxy-α-cyanocinnamic acid ester-N-vinylsuccinimide copolymer, 2,3-dicarboxy-α-cyanocinnamic acid ester -N-vinylphthalimide copolymer, 2,3-dicarboxy-α-cyanocinnamic acid ester-2-vinylfuran copolymer, 2,3-dicarboxy-α-cyanocinnamic acid ester-2-vinylbenzofuran copolymer Polymer, 2,4-dicarboxy-α-cyanocinnamic acid ester-styrene copolymer, 2,4-dicarboxy-α-cyanocinnamic acid ester-2-vinylnaphthalene copolymer, 2,4-dicarboxy -Α-cyanocinnamic acid ester-1-vinylindole copolymer, 2,4-dicarboxy-α-cyanocinnamic acid ester-9-vinyl Carbazole copolymer, 2,4-dicarboxy-α-cyanocinnamic acid ester-N-vinylsuccinimide copolymer, 2,4-dicarboxy-α-cyanocinnamic acid ester-N-vinylphthalimide copolymer, 2 , 4-dicarboxy-α-cyanocinnamic acid ester-2-vinylfuran copolymer, 2,4-dicarboxy-α-cyanocinnamic acid ester-2-vinylbenzofuran copolymer, 3,4-dicarboxy- α-cyanocinnamic acid ester-styrene copolymer, 3,4-dicarboxy-α-cyanocinnamic acid ester-2-vinylnaphthalene copolymer, 3,4-dicarboxy-α-cyanocinnamic acid ester-1- Vinyl indole copolymer, 3,4-dicarboxy-α-cyanocinnamic acid ester-9-vinyl carbazole copolymer, 3,4-dicarbo Xi-α-cyanocinnamic acid ester-N-vinylsuccinimide copolymer, 3,4-dicarboxy-α-cyanocinnamic acid ester-N-vinylphthalimide copolymer, 3,4-dicarboxy-α-cyanocinnamic leather Acid ester-2-vinylfuran copolymer, 3,4-dicarboxy-α-cyanocinnamic acid ester-2-vinylbenzofuran copolymer, 4-hydroxybenzalmalononitrile-styrene copolymer, 4-hydroxyben Zalmalononitrile-2-vinylnaphthalene copolymer, 4-hydroxybenzalmalononitrile-1-vinylindole copolymer, 4-hydroxybenzalmalononitrile-9-vinylcarbazole copolymer, 4-hydroxybenzalmalono Nitrile-N-vinylsuccinimide copolymer, 4-hydroxybenzalmalo Nitrile-N-vinylphthalimide copolymer, 4-hydroxybenzalmalononitrile-2-vinylfuran copolymer, 4-hydroxybenzalmalononitrile-2-vinylbenzofuran copolymer, 2,3-dihydroxybenzalmalono Nitrile-styrene copolymer, 2,3-dihydroxybenzalmalononitrile-2-vinylnaphthalene copolymer, 2,3-dihydroxybenzalmalononitrile-1-vinylindole copolymer, 2,3-dihydroxybenzal Malononitrile-9-vinylcarbazole copolymer, 2,3-dihydroxybenzalmalononitrile-N-vinylsuccinimide copolymer, 2,3-dihydroxybenzalmalononitrile-N-vinylphthalimide copolymer, 2,3 -Dihydroxybenzalmalononitrile-2-bi Nylfuran copolymer, 2,3-dihydroxybenzalmalononitrile-2-vinylbenzofuran copolymer, 2,4-dihydroxybenzalmalononitrile-styrene copolymer, 2,4-dihydroxybenzalmalononitrile-2- Vinylnaphthalene copolymer, 2,4-dihydroxybenzalmalononitrile-1-vinylindole copolymer, 2,4-dihydroxybenzalmalononitrile-9-vinylcarbazole copolymer, 2,4-dihydroxybenzalmalono Nitrile-N-vinylsuccinimide copolymer, 2,4-dihydroxybenzalmalononitrile-N-vinylphthalimide copolymer, 2,4-dihydroxybenzalmalononitrile-2-vinylfuran copolymer, 2,4- Dihydroxybenzalmalononitrile-2-vinylbenzo Run copolymer, 3,4-dihydroxybenzalmalononitrile-styrene copolymer, 3,4-dihydroxybenzalmalononitrile-2-vinylnaphthalene copolymer, 3,4-dihydroxybenzalmalononitrile-1- Vinyl indole copolymer, 3,4-dihydroxybenzalmalononitrile-9-vinylcarbazole copolymer, 3,4-dihydroxybenzalmalononitrile-N-vinylsuccinimide copolymer, 3,4-dihydroxybenzalmalono Nitrile-N-vinylphthalimide copolymer, 3,4-dihydroxybenzalmalononitrile-2-vinylfuran copolymer, 3,4-dihydroxybenzalmalononitrile-2-vinylbenzofuran copolymer, 4-carboxyben Zalmalononitrile-styrene copolymer, 4-cal Xibenzalmalononitrile-2-vinylnaphthalene copolymer, 4-carboxybenzalmalononitrile-1-vinylindole copolymer, 4-carboxybenzalmalononitrile-9-vinylcarbazole copolymer, 4-carboxyben Zalmalononitrile-N-vinylsuccinimide copolymer, 4-carboxybenzalmalononitrile-N-vinylphthalimide copolymer, 4-carboxybenzalmalononitrile-2-vinylfuran copolymer, 4-carboxybenzalmalono Nitrile-2-vinylbenzofuran copolymer, 2,3-dicarboxybenzalmalononitrile-styrene copolymer, 2,3-dicarboxybenzalmalononitrile-2-vinylnaphthalene copolymer, 2,3-di Carboxybenzalmalononitrile-1-vinylin Dole copolymer, 2,3-dicarboxybenzalmalononitrile-9-vinylcarbazole copolymer, 2,3-dicarboxybenzalmalononitrile-N-vinylsuccinimide copolymer, 2,3-dicarboxyben Zalmalononitrile-N-vinylphthalimide copolymer, 2,3-dicarboxybenzalmalononitrile-2-vinylfuran copolymer, 2,3-dicarboxybenzalmalononitrile-2-vinylbenzofuran copolymer, 2,4-dicarboxybenzalmalononitrile-styrene copolymer, 2,4-dicarboxybenzalmalononitrile-2-vinylnaphthalene copolymer, 2,4-dicarboxybenzalmalononitrile-1-vinylindole Copolymer, 2,4-dicarboxybenzalmalononitrile-9-vinylcarbazo Copolymer, 2,4-dicarboxybenzalmalononitrile-N-vinylsuccinimide copolymer, 2,4-dicarboxybenzalmalononitrile-N-vinylphthalimide copolymer, 2,4-dicarboxybenzal Malononitrile-2-vinylfuran copolymer, 2,4-dicarboxybenzalmalononitrile-2-vinylbenzofuran copolymer, 3,4-dicarboxybenzalmalononitrile-styrene copolymer, 3,4- Dicarboxybenzalmalononitrile-2-vinylnaphthalene copolymer, 3,4-dicarboxybenzalmalononitrile-1-vinylindole copolymer, 3,4-dicarboxybenzalmalononitrile-9-vinylcarbazole copolymer Polymer, 3,4-dicarboxybenzalmalononitrile-N-vinylsuccinimide Polymer, 3,4-dicarboxybenzalmalononitrile-N-vinylphthalimide copolymer, 3,4-dicarboxybenzalmalononitrile-2-vinylfuran copolymer, 3,4-dicarboxybenzalmalono Nitrile-2-vinylbenzofuran copolymers are preferred.

  The resin having the residue unit represented by the general formula (1) of the present invention may contain other monomer residue units other than the residue units described above, as long as it does not exceed the scope of the present invention. Other monomer residue units include acrylic acid residue units; acrylate residue units such as methyl acrylate residue units, ethyl acrylate residue units, and butyl acrylate residue units; methacrylic acid Residue unit; Methacrylic acid ester residue unit such as methyl methacrylate residue unit, ethyl methacrylate residue unit and butyl methacrylate residue unit; Acrylic acid hydroxy ester residue such as 2-hydroxymethyl acrylate residue unit Base unit; methacrylic acid hydroxy ester residue unit such as 2-hydroxymethyl methacrylate unit; vinyl acetate residue unit, vinyl propionate residue unit, etc. Ester residue units; Acrylonitrile residue units; Methacrylonitrile residue units; Vinyl ether residue units such as methyl vinyl ether residue units, ethyl vinyl ether residue units, butyl vinyl ether residue units; Diethyl fumarate residue units, etc. Fumarate residue units; N-methylmaleimide residue units, N-cyclohexylmaleimide residue units, N-phenylmaleimide residue units and other N-substituted maleimide residue units; ethylene residue units, propylene residues One type or two or more types selected from olefin residue units such as units can be mentioned.

  Since the resin having a residue unit represented by the general formula (1) of the present invention has excellent mechanical properties, a standard obtained from an elution curve measured by gel permeation chromatography (GPC). The number average molecular weight in terms of polystyrene is preferably 3,000 to 500,000, more preferably 5,000 to 300,000, and particularly preferably 5,000 to 200,000.

  The composition of the resin having a residue unit represented by the general formula (1) of the present invention is more excellent in retardation characteristics and transparency when used as an optical compensation film. 20 mol% or more of the residue unit shown is preferable, 30 mol% or more of the residue unit shown by the general formula (1) is more preferable, and 35 mol% or more of the residue unit shown by the general formula (1) is particularly preferable.

  As a method for producing a resin having a residue unit represented by the general formula (1), it may be produced by any method as long as the resin is obtained. For example, it can be produced by performing radical polymerization using a monomer related to the residue unit represented by the general formula (1) and a monomer copolymerizable therewith. As the radical polymerization method, for example, any of a bulk polymerization method, a solution polymerization method, a suspension polymerization method, a precipitation polymerization method, an emulsion polymerization method and the like can be employed.

  Examples of the polymerization initiator used for radical polymerization include benzoyl peroxide, lauryl peroxide, octanoyl peroxide, acetyl peroxide, di-t-butyl peroxide, t-butylcumyl peroxide, and dicumyl peroxide. , Organic peroxides such as t-butylperoxyacetate, t-butylperoxybenzoate, 2,5-dimethyl-2,5-di (2-ethylhexanoylperoxy) hexane; 2,2′-azobis ( 2,4-dimethylvaleronitrile), 2,2′-azobis (2-butyronitrile), 2,2′-azobisisobutyronitrile, dimethyl-2′-azobisisobutyrate, 1,1′-azobis And azo initiators such as (cyclohexane-1-carbonitrile).

  And there is no restriction | limiting in particular as a solvent which can be used when employ | adopting solution polymerization method, suspension polymerization method, precipitation polymerization method, and emulsion polymerization method, For example, aromatic solvents, such as benzene, toluene, xylene; methanol, ethanol, Alcohol solvents such as propanol and butanol; cyclohexane; dioxane; tetrahydrofuran; acetone; methyl ethyl ketone; N, N-dimethylformamide; dimethyl sulfoxide; isopropyl acetate; water and the like.

  Moreover, since the polymerization temperature at the time of performing radical polymerization can be suitably set according to the decomposition temperature of the polymerization initiator and the control of the reaction is easy, it is generally performed in the range of 30 to 150 ° C. It is preferable.

  The resin having a residue unit represented by the general formula (1) may be obtained via a precursor.

  In the present invention, the resin having positive intrinsic birefringence is not particularly limited as long as an optical compensation film excellent in retardation characteristics can be obtained using the resin. For example, cellulose resin, polycarbonate, cyclic polyolefin, polyethylene, Examples thereof include polypropylene, polyester, polyimide, polyamide, polyurethane, and the like. Cellulosic resins are preferred because an optical compensation film having more excellent retardation characteristics can be obtained.

  In the present invention, when a cellulosic resin is used as a resin having positive intrinsic birefringence, when it is used as an optical compensation film, it is excellent in retardation characteristics and transparency, has a large in-plane retardation Re, and has a stretch processability Therefore, the cellulose resin represented by the following general formula (4) is preferable.

（４）

(4)

Wherein R _{16 to} R ₁₈ are each independently hydrogen, a linear alkyl group having 1 to 12 carbon atoms, a branched alkyl group having 1 to 12 carbon atoms, a cyclic group having 3 to 14 carbon atoms, or acyl. Group (—C (═O) X ₃₀ ) (where X ₃₀ is a linear alkyl group having 1 to 12 carbon atoms, a branched alkyl group having 1 to 12 carbon atoms, or a cyclic group having 3 to 14 carbon atoms). Show.)
Here, the cellulose resin represented by the general formula (4) is a polymer in which β-glucose units are linearly polymerized, and part or all of hydroxyl groups at the 2nd, 3rd and 6th positions of the glucose unit. Is a polymer substituted.

Examples of the linear alkyl group having 1 to 12 carbon atoms in R _{16 to} R ₁₈ include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group, and an n-hexyl group. Examples of the branched alkyl group having 1 to 12 carbon atoms include isopropyl group, sec-butyl group, tert-butyl group, isobutyl group and the like, and examples of the cyclic group having 3 to 14 carbon atoms include: A cyclopropyl group, a cyclobutyl group, a cyclohexyl group, a phenyl group, a naphthyl group, etc. are mentioned.
Examples of the linear alkyl group having 1 to 12 carbon atoms in X _30, for example, a methyl group, an ethyl group, n- propyl group, n- butyl group, n- pentyl group, n- hexyl, and the like, carbon Examples of the branched alkyl group having 1 to 12 include isopropyl group, sec-butyl group, tert-butyl group, isobutyl group and the like, and examples of the cyclic group having 3 to 14 carbon atoms include cyclopropyl group. , Cyclobutyl group, cyclohexyl group, phenyl group, naphthyl group and the like.
Examples of R _{16 to} R ₁₈ in the general formula (4) of the present invention include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an isopropyl group, a sec-butyl group, a tert-butyl group, and an isobutyl group. , Cyclopropyl group, cyclobutyl group, cyclohexyl group, phenyl group, naphthyl group, acetyl group, propionyl group, butyryl group, pentanoyl group, hexanoyl group, heptanoyl group, isobutyryl group, tert-butyryl group, cyclohexanoyl group, benzoyl group And a naphthoyl group. Among these, a methyl group, an ethyl group, a propyl group, an acetyl group, a propionyl group, and a butyryl group are preferable because solubility and compatibility are further improved.

  The substitution degree of substitution through the oxygen atom of the hydroxyl group of cellulose in the cellulose resin of the present invention is the ratio of substitution of the hydroxyl group of cellulose for each of the 2-position, 3-position and 6-position (100% substitution) Means the degree of substitution 3), and the degree of substitution is preferably 1.5 to 3.0, more preferably 1.8 to 2.8 from the viewpoint of solubility, compatibility and stretch processability. .

  Specific examples of the cellulose resin of the present invention include methyl cellulose, ethyl cellulose, triacetyl cellulose, cellulose acetate, cellulose acetate butyrate, cellulose acetate propionate, and the like. Since a compensation film is obtained, ethyl cellulose, cellulose acetate butyrate, and cellulose acetate propionate are preferable.

  Since the cellulose resin of the present invention has excellent mechanical properties and excellent moldability during film formation, standard polystyrene obtained from an elution curve measured by gel permeation chromatography (GPC). The converted number average molecular weight (Mn) is preferably 1,000 to 1,000,000, and more preferably 5,000 to 200,000.

  The resin composition of the present invention is obtained by blending a resin having a residue unit represented by the general formula (1) and a resin having positive intrinsic birefringence, and when used as an optical compensation film, The optical compensation film is characterized by exhibiting a target retardation characteristic. That is, a resin having a residue unit represented by general formula (1) exhibits negative birefringence, and a resin having a residue unit represented by general formula (1) and a resin having positive intrinsic birefringence Exhibiting excellent compatibility, it is possible to obtain an optical compensation film having practical transparency and excellent retardation characteristics when using the resin composition according to the present invention obtained by blending them. It can be done.

  The ratio of the composition of the resin having the residue unit represented by the general formula (1) and the resin having positive intrinsic birefringence in the resin composition of the present invention is suitable for controlling the retardation when the retardation film is used. Therefore, it is preferably 1 to 90% by weight of the resin having the residue unit represented by the general formula (1) and 99 to 10% by weight of the resin having positive intrinsic birefringence. More preferably, it is 10 to 85% by weight of the resin having the residue unit represented by the general formula (1) and 90 to 15% by weight of the resin having a positive intrinsic birefringence, and particularly preferably the general formula (1). 20 to 80% by weight of resin having a residue unit and 80 to 20% by weight of resin having positive intrinsic birefringence.

  As a blending method, methods such as melt blending and solution blending can be used. The melt blending method is a method of manufacturing by melting and kneading a resin by heating. The solution blending method is a method in which a resin is dissolved in a solvent and blended. Solvents used for solution blending include, for example, chlorinated solvents such as methylene chloride and chloroform; aromatic solvents such as toluene and xylene; ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclopentanone, and cyclohexanone; ethyl acetate, An ester solvent such as butyl acetate; an alcohol solvent such as methanol, ethanol, or propanol; an ether solvent such as dioxane or tetrahydrofuran; dimethylformamide, N-methylpyrrolidone, or the like can be used. Each resin and additive can be dissolved in a solvent and then blended. The powder, pellets, etc. of each resin can be kneaded and then dissolved in the solvent.

  The resin composition of the present invention may contain an antioxidant in order to improve the thermal stability when making an optical film. Antioxidants include, for example, hindered phenol antioxidants, phosphorus antioxidants, sulfur antioxidants, lactone antioxidants, amine antioxidants, hydroxylamine antioxidants, vitamin E series An antioxidant, other antioxidants, etc. are mentioned, and these antioxidants may be used alone or in combination of two or more.

  The resin composition of the present invention may contain a hindered amine light stabilizer or an ultraviolet absorber in order to enhance the weather resistance when making an optical film. Examples of the ultraviolet absorber include benzotriazole, benzophenone, triazine, benzoate and the like.

  The resin composition of the present invention is a compound known as a so-called plasticizer, for the purpose of improving mechanical properties, imparting flexibility, imparting water absorption resistance, reducing water vapor transmission rate, adjusting retardation, etc. when used as an optical film. The plasticizer may be added, and examples of the plasticizer include phosphoric acid esters and carboxylic acid esters. Acrylic polymers are also used.

  Examples of phosphate esters include triphenyl phosphate, tricresyl phosphate, phenyl diphenyl phosphate, and the like.

  Examples of the carboxylic acid ester include phthalic acid ester, citric acid ester, fatty acid ester, glycerol ester, and alkylphthalyl alkyl glycolate. Examples of the phthalate ester include dimethyl phthalate, diethyl phthalate, dicyclohexyl phthalate, dioctyl phthalate, and diethyl hexyl phthalate. Examples of the citrate ester include acetyl triethyl citrate and acetyl tributyl citrate. . Examples of the fatty acid ester include butyl oleate, methylacetyl ricinoleate, dibutyl sebacate, and the like, and examples of the glycerol ester include triacetin, trimethylolpropane tribenzoate, and the like. Examples of the rate include methyl phthalyl methyl glycolate, ethyl phthalyl ethyl glycolate, propyl phthalyl propyl glycolate, butyl phthalyl butyl glycolate, octyl phthalyl octyl glycolate, methyl phthalyl ethyl glycolate, ethyl phthalate Methyl methacrylate, ethyl phthalyl propyl glycolate, propyl phthalyl ethyl glycolate, methyl phthalyl propyl glycolate, methyl phthalyl butyl glycolate, ethyl Phthalyl butyl glycolate, butyl phthalyl methyl glycolate, butyl phthalyl ethyl glycolate, propyl phthalyl butyl glycolate, butyl phthalyl propyl glycolate, methyl phthalyl octyl glycolate, ethyl phthalyl octyl glycolate, octyl phthalate Examples include rumethyl glycolate and octyl phthalyl ethyl glycolate. These plasticizers may be used alone or in combination of two or more.

  The resin composition of the present invention may contain an additive having an aromatic hydrocarbon ring or an aromatic heterocycle for the purpose of adjusting the phase difference in forming an optical compensation film. The birefringence Δn represented by the following formula (A) of the additive used for the purpose of adjusting the phase difference is not particularly limited, but is preferably 0 because it becomes an optical compensation film with more excellent optical characteristics. 0.05 or more, more preferably 0.05 to 0.5, and particularly preferably 0.1 to 0.5. The Δn of the additive can be obtained by molecular orbital calculation.

Δn = nx−ny (A)
(In the formula, nx represents the refractive index in the slow axis direction of the additive molecule, and ny represents the refractive index in the fast axis direction of the additive molecule.)
When an additive having an aromatic hydrocarbon ring or aromatic heterocycle is contained in the resin composition of the present invention, the number of the aromatic hydrocarbon ring or aromatic heterocycle in the molecule in the additive Although there is no restriction | limiting in particular, Since it becomes an optical compensation film excellent in the optical characteristic, Preferably it is 1-12 pieces, More preferably, it is 1-8 pieces. Examples of the aromatic hydrocarbon ring include a 5-membered ring, a 6-membered ring, a 7-membered ring, or a condensed ring composed of two or more aromatic rings. Examples of the aromatic heterocycle include a furan ring. Thiophene ring, pyrrole ring, oxazole ring, thiazole ring, imidazole ring, triazole ring, pyridine ring, pyrimidine ring, pyrazine ring, 1,3,5-triazine ring and the like.

  The aromatic hydrocarbon ring or aromatic heterocycle may have a substituent. Examples of the substituent include a hydroxyl group, an ether group, a carbonyl group, an ester group, a carboxylic acid residue, an amino group, and an imino group. Amide group, imide group, cyano group, nitro group, sulfonyl group, sulfonic acid residue, phosphonyl group, phosphonic acid residue and the like.

  Examples of the additive having an aromatic hydrocarbon ring or aromatic heterocycle used in the present invention include tricresyl phosphate, trixylenyl phosphate, triphenyl phosphate, 2-ethylhexyl diphenyl phosphate, cresyl diphenyl phosphate, Phosphate ester compounds such as bisphenol A bis (diphenyl phosphate); dimethyl phthalate, diethyl phthalate, dibutyl phthalate, dihexyl phthalate, dinormal octyl phthalate, 2-ethylhexyl phthalate, diisooctyl phthalate, dicapryl phthalate, dinonyl phthalate, diisononyl Phthalate compounds such as phthalate, didecyl phthalate, diisodecyl phthalate; tributyl trimellitate, tri-normal hex Trimellitic acid ester-based compounds such as rutrimellitate, tri (2-ethylhexyl) trimellitate, tri-normal octyl trimellitate, tri-isoctyl trimellitate, tri-isodecyl trimellitate; tri (2-ethylhexyl) pyromellitate, Pyromellitic acid such as tetrabutyl pyromellitate, tetra-normal hexyl pyromellitate, tetra (2-ethylhexyl) pyromellitate, tetra-normal octyl pyromellitate, tetra-isooctyl pyromellitate, tetra-isodecyl pyromellitate Ester compounds; benzoic acid ester compounds such as ethyl benzoate, isopropyl benzoate, ethyl paraoxybenzoate; phenyl salicylate, p-octylphenyl salicylate, p-tert-butylphenol Salicylic acid ester compounds such as rusalicylate; Glycolic acid ester compounds such as methylphthalylethyl glycolate, ethylphthalylethyl glycolate, butylphthalylbutyl glycolate; 2- (2′-hydroxy-5′-t- Benzotriazole compounds such as butylphenyl) benzotriazole, 2- (2′-hydroxy-3 ′, 5′-di-t-butylphenyl) benzotriazole; 2-hydroxy-4-methoxybenzophenone, 2,2′- Benzophenone compounds such as dihydroxy-4-methoxybenzophenone, 2,4-dihydroxybenzophenone, 2,2 ′, 4,4′-tetrahydroxybenzophenone, 2-hydroxy-4-methoxy-5-sulfobenzophenone, N-benzenesulfone Sulfons such as amides Mido compounds, 2,4-diphenyl-6- (2-hydroxy-4-methoxyphenyl) -1,3,5-triazine, 2,4-diphenyl-6- (2-hydroxy-4-ethoxyphenyl)- 1,3,5-triazine, 2,4-diphenyl- (2-hydroxy-4-propoxyphenyl) -1,3,5-triazine, 2,4-diphenyl- (2-hydroxy-4-butoxyphenyl)- Triazine compounds such as 1,3,5-triazine and the like are mentioned, and since an optical compensation film having more excellent retardation characteristics can be obtained, tricresyl phosphate, 2-ethylhexyl diphenyl phosphate, 2-hydroxy-4-methoxy Benzophenone and 2,2 ′, 4,4′-tetrahydroxybenzophenone are preferred, and these may be one or more as required. It can be used in combination.

  When the resin composition of the present invention contains an additive having an aromatic hydrocarbon ring or an aromatic heterocycle, it is preferably an aromatic hydrocarbon ring or an aromatic heterocycle from the viewpoint of optical properties and mechanical properties. The ratio of the additive having a ring is 0.01 to 30% by weight, more preferably 0.01 to 20% by weight, and particularly preferably 0.01 to 15% by weight.

  The resin composition of the present invention contains other polymers, surfactants, polymer electrolytes, conductive complexes, pigments, dyes, antistatic agents, antiblocking agents, lubricants and the like within the scope of the invention. May be.

  The resin composition of the present invention is suitable as an optical film, and an optical film using the resin composition is particularly suitable as an optical compensation film.

  The thickness of the optical film of the present invention is preferably from 5 to 200 μm, more preferably from 5 to 150 μm, particularly preferably from 5 to 120 μm, from the viewpoints of handleability of the film and suitability for thinning of the optical member.

  Since the optical film of the present invention has good image quality characteristics, the light transmittance is preferably 80% or more, and more preferably 85% or more.

  Since the optical film of the present invention has good image quality characteristics, the haze (cloudiness) of the film is preferably 2% or less, and more preferably 1% or less.

  The retardation characteristics of the optical compensation film of the present invention are preferably such that the in-plane retardation (Re) represented by the following formula (a) is 50 to 500 nm, more preferably 100 to 450 nm, and particularly preferably 100 to 400 nm. The Nz coefficient represented by the following formula (b) is preferably 0 ≦ Nz ≦ 1.0, more preferably 0.30 ≦ Nz ≦ 0.65, and particularly preferably 0.35 ≦ Nz ≦ 0.60. Is preferred. The phase difference characteristic at this time is measured using a fully automatic birefringence meter (manufactured by AXOMETRICS, trade name: AxoScan) under a measurement wavelength of 589 nm.

  These are retardation characteristics that are difficult to develop with conventional optical compensation films.

Re = (nx−ny) × d (a)
Nz = (nx-nz) / (nx-ny) (b)
(Where nx represents the refractive index in the direction of the stretching axis in the film plane, ny represents the refractive index in the direction perpendicular to the stretching axis in the film plane, and nz represents the refractive index outside the film plane (thickness direction). D indicates the film thickness.)
As the wavelength dispersion characteristic of the optical compensation film of the present invention, the ratio Re (450) / Re (550) of the retardation at 450 nm to the retardation at 550 nm is preferably 0.60 <Re (450) in order to suppress color misregistration. /Re(550)<1.10, more preferably 0.70 <Re (450) / Re (550) <1.02, and particularly preferably 0.75 <Re (450) / Re (550). ) <1.00.

  As a method for producing the optical film of the present invention, any method may be used as long as the optical film of the present invention can be produced, because an optical film excellent in optical properties, heat resistance, surface properties and the like can be obtained. It is preferable to produce by a solution casting method. Here, the solution casting method is a method of obtaining an optical film by casting a resin solution (generally referred to as a dope) on a support substrate and then evaporating the solvent by heating. As a casting method, for example, a T-die method, a doctor blade method, a bar coater method, a roll coater method, a lip coater method or the like is used. In general, a method of continuously extruding is used. Examples of the support substrate used include a glass substrate, a metal substrate such as stainless steel and ferrotype, and a plastic substrate such as polyethylene terephthalate. In order to industrially continuously form a substrate having high surface properties and optical homogeneity, a metal substrate having a mirror-finished surface is preferably used. In the solution casting method, the viscosity of the resin solution is an extremely important factor when producing an optical film with excellent thickness accuracy and surface smoothness. The viscosity of the resin solution depends on the resin concentration, molecular weight, and type of solvent. It depends.

  The viscosity of the resin solution when producing the optical film of the present invention can be adjusted by the molecular weight of the polymer, the concentration of the polymer, and the type of solvent. The viscosity of the resin solution is not particularly limited, but is preferably 100 to 10000 cps, more preferably 300 to 5000 cps, and particularly preferably 500 to 3000 cps in order to make film coating easier.

  As a method for producing the optical compensation film of the present invention, for example, a resin composition containing a resin having a residue unit represented by the general formula (1) and a resin having positive intrinsic birefringence is dissolved in a solvent. The obtained resin solution is cast on a substrate, and after drying, it is peeled off from the substrate.

  In the present invention, the out-of-plane retardation (Rth) can be controlled by the concentration of the resin contained in the resin composition, the molecular weight of the resin, the type of solvent, and the film-forming drying temperature.

  The optical compensation film of the present invention is preferably uniaxially stretched or unbalanced biaxially stretched to develop in-plane retardation (Re). As a method of stretching the optical compensation film, it is possible to use a longitudinal uniaxial stretching method by roll stretching, a transverse uniaxial stretching method by tenter stretching, an unbalanced sequential biaxial stretching method or an unbalanced simultaneous biaxial stretching method by combining these it can. Moreover, in this invention, a phase difference characteristic can be expressed, without using the special extending | stretching method which extends | stretches under the effect | action of the shrinkage force of a heat-shrinkable film.

  The thickness of the optical compensation film at the time of stretching is preferably from 10 to 200 μm, more preferably from 30 to 150 μm, particularly preferably from 30 to 120 μm, from the viewpoint of easiness of stretching treatment and suitability for thinning of the optical member. .

  The stretching temperature is not particularly limited, but is preferably 50 to 200 ° C., more preferably 100 to 180 ° C., because good retardation characteristics can be obtained. The stretching ratio of uniaxial stretching is preferably 1.05 to 3.5 times, and more preferably 1.1 to 3.0 times because good retardation characteristics can be obtained. Since the stretch ratio of unbalanced biaxial stretching can provide good retardation characteristics, 1.05 to 3.5 times are preferable in the length direction, 1.1 to 3.0 times are more preferable, and the width direction 1.0 to 1.2 times is preferable, and 1.0 to 1.1 times is more preferable. The in-plane retardation (Re) can be controlled by the stretching temperature and the stretching ratio.

  The optical film of this invention can be laminated | stacked with the film containing other resin as needed. Examples of other resins include polyether sulfone, polyarylate, polyethylene terephthalate, polynaphthalene terephthalate, polycarbonate, cyclic polyolefin, maleimide resin, fluorine resin, polyimide, and the like. It is also possible to laminate a hard coat layer or a gas barrier layer.

  EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited to these Examples.

  In addition, the various physical properties shown by an Example were measured with the following method.

<Analysis of polymer>
Using a nuclear magnetic resonance measuring apparatus (manufactured by JEOL, trade name JNM-ECZ400S / L1), it was obtained by proton nuclear magnetic resonance spectroscopy ( ¹ H-NMR) spectrum analysis. ^Also, for those be determined by 1 H-NMR spectrum analysis is difficult, elemental analyzer (Perkin Elmer Ltd., trade name 2400II) used was determined by CHN elemental analysis.

<Measurement of number average molecular weight>
Using a gel permeation chromatography (GPC) apparatus (trade name HLC8320GPC (equipped with column GMHHR-H) manufactured by Tosoh Corporation) using tetrahydrofuran or N, N-dimethylformamide as a solvent at 40 ° C., standard It calculated | required as a polystyrene conversion value.

<Transparency evaluation method>
The total light transmittance and haze of the film were measured using a haze meter (trade name NDH5000, manufactured by Nippon Denshoku Industries Co., Ltd.).

<Measurement of refractive index>
An Abbe refractometer (manufactured by Atago) was used and measured according to JIS K 7142 (1981 version).
<Measurement of phase difference characteristics>
An in-plane retardation Re, an out-of-plane retardation Rth, and an Nz coefficient of the optical compensation film were measured using a sample tilt type automatic birefringence meter (manufactured by AXOMETRICS, trade name: AxoScan) using light having a wavelength of 589 nm.
<Measurement of wavelength dispersion characteristics>
Using a sample tilt type automatic birefringence meter (manufactured by AXOMETRICS, trade name: AxoScan), the wavelength of the optical compensation film as a ratio of the phase difference Re (450) due to light having a wavelength of 450 nm and the phase difference Re (550) due to light having a wavelength of 550 nm Dispersion characteristics were measured.

Synthesis Example 1 (Polymerization of 4-carboxy-α-ethyl cyanocinnamate / styrene copolymer)
Glass ampoule with a capacity of 50 mL, 15 g of ethyl 4-carboxy-α-cyanocinnamate, 6.4 g of styrene, 2,5-dimethyl-2,5-di (2-ethylhexanoylperoxy) hexane 0 as a polymerization initiator .44 g and N, N-dimethylformamide 45 g were added, and after nitrogen substitution and depressurization were repeated, the mixture was sealed under reduced pressure. The ampoule was placed in a constant temperature bath at 62 ° C. and kept for 48 hours to carry out radical polymerization. After completion of the polymerization reaction, the polymer was taken out from the ampoule and dissolved in 75 g of tetrahydrofuran. This polymer solution was dropped into 500 mL of methanol and precipitated, and then vacuum-dried at 60 ° C. for 10 hours to obtain 13.8 g of a 4-carboxy-α-ethyl cyanocinnamate / styrene copolymer ( Yield: 65%).

  The number average molecular weight of the obtained 4-carboxy-α-ethyl cyanocinnamate / styrene copolymer was 29,000.

The copolymer composition was confirmed by ¹ H-NMR measurement to be 4-carboxy-α-cyanocyanocinnamate residue unit / styrene residue unit = 35/65 (mol%).

Synthesis Example 2 (Polymerization of 4-carboxybenzalmalononitrile / 1-vinylindole copolymer)
In a 50 mL glass ampule, 5.0 g of 4-carboxybenzalmalononitrile, 3.6 g of 1-vinylindole, 2,5-dimethyl-2,5-di (2-ethylhexanoylperoxy) as a polymerization initiator 0.18 g of hexane and 8.5 g of N, N-dimethylformamide were added, and after nitrogen substitution and depressurization were repeated, the mixture was sealed under reduced pressure. The ampoule was placed in a constant temperature bath at 62 ° C. and kept for 48 hours to carry out radical polymerization. After completion of the polymerization reaction, the polymer was taken out from the ampoule and dissolved in 25 g of tetrahydrofuran. This polymer solution was dropped into 500 mL of methanol and precipitated, and then vacuum-dried at 60 ° C. for 10 hours to obtain 5.0 g of 4-carboxybenzalmalononitrile / 1-vinylindole copolymer ( Yield: 58%).

  The number average molecular weight of the obtained 4-carboxybenzalmalononitrile / 1-vinylindole copolymer was 23,000.

  Moreover, it was confirmed by CHN elemental analysis that the copolymer composition was 4-carboxybenzalmalononitrile residue unit / 1-vinylindole residue unit = 33/67 (mol%).

Synthesis Example 3 (Polymerization of 4-hydroxy-α-ethyl cyanocinnamate / 9-vinylcarbazole copolymer)
In a glass ampule with a capacity of 50 mL, 5.0 g of ethyl 4-hydroxy-α-cyanocinnamate, 4.4 g of 9-vinylcarbazole, 2,5-dimethyl-2,5-di (2-ethylhexanoyl) which is a polymerization initiator Peroxy) hexane (0.17 g) and tetrahydrofuran (8.5 g) were added, and after nitrogen substitution and depressurization were repeated, the mixture was sealed under reduced pressure. The ampoule was placed in a constant temperature bath at 62 ° C. and kept for 48 hours to carry out radical polymerization. After completion of the polymerization reaction, the polymer was taken out from the ampoule and dissolved in 25 g of tetrahydrofuran. This polymer solution was dropped into 500 mL of methanol and precipitated, and then vacuum-dried at 60 ° C. for 10 hours to obtain 7.7 g of 4-hydroxy-α-ethyl cyanocinnamate / 9-vinylcarbazole copolymer. Obtained (yield: 82%).

  The number average molecular weight of the obtained 4-hydroxy-α-cyanocyanocinnamate / 9-vinylcarbazole copolymer was 22,000.

The copolymer composition was confirmed by ¹ H-NMR measurement to be 4-hydroxy-α-cyanocyanocinnamate residue unit / 9-vinylcarbazole residue unit = 42/58 (mol%).

Synthesis Example 4 (polymerization of 4-hydroxybenzalmalononitrile / 2-vinylnaphthalene copolymer)
In a glass ampoule with a capacity of 50 mL, 5.0 g of 4-hydroxybenzalmalononitrile, 4.5 g of 2-vinylnaphthalene, and 2,5-dimethyl-2,5-di (2-ethylhexanoylperoxy) as a polymerization initiator After adding 0.21 g of hexane and 10 g of tetrahydrofuran, repeating nitrogen substitution and depressurization, the mixture was sealed under reduced pressure. The ampoule was placed in a constant temperature bath at 62 ° C. and kept for 48 hours to carry out radical polymerization. After completion of the polymerization reaction, the polymer was taken out from the ampoule and dissolved in 25 g of tetrahydrofuran. This polymer solution was dropped into 500 mL of methanol and precipitated, and then vacuum-dried at 60 ° C. for 10 hours to obtain 6.2 g of 4-hydroxybenzalmalononitrile / 2-vinylnaphthalene copolymer ( Yield: 65%).

  The number average molecular weight of the obtained 4-hydroxybenzalmalononitrile / 2-vinylnaphthalene copolymer was 12,000.

  The copolymer composition was confirmed to be 4-hydroxybenzalmalononitrile residue unit / 2-vinylnaphthalene residue unit = 43/57 (mol%) by CHN elemental analysis.

Synthesis Example 5 (polymerization of 4-hydroxy-α-cyanocyanocinnamate / N-vinylsuccinimide copolymer)
In a glass ampule with a capacity of 50 mL, 5.0 g of isobutyl 4-hydroxy-α-cyanocinnamate, 2.6 g of N-vinylsuccinimide, and 2,5-dimethyl-2,5-di (2-ethylhexanoyl) as a polymerization initiator Peroxy) hexane (0.15 g) and tetrahydrofuran (8.5 g) were added, and after nitrogen substitution and depressurization were repeated, the mixture was sealed under reduced pressure. The ampoule was placed in a constant temperature bath at 62 ° C. and kept for 48 hours to carry out radical polymerization. After completion of the polymerization reaction, the polymer was taken out from the ampoule and dissolved with 25 g of N, N-dimethylformamide. This polymer solution was dropped into 500 mL of methanol and precipitated, and then vacuum dried at 60 ° C. for 10 hours to obtain 5.5 g of 4-hydroxy-α-cyanocinnamic acid isobutyl / N-vinylsuccinimide copolymer. Obtained (yield: 73%).

  The number average molecular weight of the obtained 4-hydroxy-α-cyanocyanocinnamate / N-vinylsuccinimide copolymer was 16,000.

The copolymer composition was confirmed to be 4-hydroxy-α-cyanocinnamic acid isobutyl residue unit / N-vinylsuccinimide residue unit = 46/54 (mol%) by ¹ H-NMR measurement.

Synthesis Example 6 (polymerization of ethyl 3,4-dihydroxy-α-cyanocinnamate / N-vinylphthalimide copolymer)
In a glass ampule with a capacity of 50 mL, 5.0 g of ethyl 3,4-dihydroxy-α-cyanocinnamate, 3.7 g of N-vinylphthalimide, and 2,5-dimethyl-2,5-di (2-ethyl) as a polymerization initiator Hexanoylperoxy) hexane (0.15 g) and tetrahydrofuran (8.5 g) were added, and after nitrogen substitution and depressurization were repeated, the mixture was sealed under reduced pressure. The ampoule was placed in a constant temperature bath at 62 ° C. and kept for 48 hours to carry out radical polymerization. After completion of the polymerization reaction, the polymer was taken out from the ampoule and dissolved with 25 g of N, N-dimethylformamide. This polymer solution was dropped into 500 mL of methanol and precipitated, and then vacuum-dried at 60 ° C. for 10 hours to obtain a 3,4-dihydroxy-α-cyanocyanocinnamate / N-vinylphthalimide copolymer. 4 g was obtained (yield: 73%).

  The number average molecular weight of the obtained 3,4-dihydroxy-α-cyanocyanocinnamic acid / N-vinylphthalimide copolymer was 21,000.

Moreover, it is confirmed by ¹ H-NMR measurement that the copolymer composition is 3,4-dihydroxy-α-cyanocyanocinnamate residue unit / N-vinylphthalimide residue unit = 41/59 (mol%). did.

Synthesis Example 7 (polymerization of 4-carboxy-3-hydroxybenzalmalononitrile / 2-vinylfuran copolymer)
In a glass ampoule with a capacity of 75 mL, 15 g of 4-carboxy-3-hydroxybenzalmalononitrile, 6.6 g of 2-vinylfuran, 2,5-dimethyl-2,5-di (2-ethylhexanoyl parper as a polymerization initiator) Oxy) 0.50 g of hexane and 30 g of tetrahydrofuran were added, and after nitrogen substitution and depressurization were repeated, the mixture was sealed under reduced pressure. The ampoule was placed in a constant temperature bath at 62 ° C. and kept for 48 hours to carry out radical polymerization. After completion of the polymerization reaction, the polymer was taken out from the ampoule and dissolved in 75 g of tetrahydrofuran. This polymer solution was dropped into 1500 mL of methanol and precipitated, and then vacuum-dried at 60 ° C. for 10 hours to obtain 12.6 g of 4-carboxy-3-hydroxybenzalmalononitrile / 2-vinylfuran copolymer. (Yield: 58%) was obtained.

  The number average molecular weight of the obtained 4-carboxy-3-hydroxybenzalmalononitrile / 2-vinylfuran copolymer was 15,000.

  Moreover, it was confirmed by CHN elemental analysis that the copolymer composition was 4-carboxy-3-hydroxybenzalmalononitrile residue unit / 2-vinylfuran residue unit = 36/64 (mol%).

Synthesis Example 8 (polymerization of 4-butyl-α-cyanocyanocinnamate / 9-vinylcarbazole copolymer)
In a glass ampule with a capacity of 50 mL, 5.0 g of isobutyl 4-hydroxy-α-cyanocinnamate, 3.9 g of 9-vinylcarbazole, and 2,5-dimethyl-2,5-di (2-ethylhexanoyl) as a polymerization initiator Peroxy) hexane (0.14 g) and tetrahydrofuran (8.0 g) were added, and after nitrogen substitution and depressurization were repeated, the mixture was sealed under reduced pressure. The ampoule was placed in a constant temperature bath at 62 ° C. and kept for 48 hours to carry out radical polymerization. After completion of the polymerization reaction, the polymer was taken out from the ampoule and dissolved in 25 g of tetrahydrofuran. This polymer solution was dropped into 500 mL of methanol and precipitated, and then vacuum-dried at 60 ° C. for 10 hours to obtain 7.5 g of 4-hydroxy-α-isobutyl cinnamate / 9-vinylcarbazole copolymer. Obtained (yield: 85%).

  The number average molecular weight of the obtained 4-hydroxy-α-isobutyl cinnamate / 9-vinylcarbazole copolymer was 12,000.

  Moreover, it was confirmed by CHN elemental analysis that the copolymer composition was 4-hydroxy-α-isobutyl cinnamate residue unit / 9-vinylcarbazole residue unit = 46/54 (mol%).

Example 1
2.0 g of ethyl 4-carboxy-α-cyanocinnamate / styrene copolymer obtained in Synthesis Example 1, ethyl cellulose (ETHOCEL standard 100 manufactured by Dow Chemical Co., Ltd.) as a resin having positive intrinsic birefringence, 10 g of molecular weight Mn = 55,000, molecular weight Mw = 176,000, Mw / Mn = 3.2, total substitution degree DS = 2.5) was dissolved in a toluene / methyl ethyl ketone = 6/4 (weight ratio) solution and 15 It was made into a weight% resin solution, poured on a polyethylene terephthalate film with a coater, dried at 40 ° C. and then dried at 150 ° C. to obtain a film having a width of 150 mm (ethyl cellulose: 83% by weight, 4-carboxyl). -Ethyl α-cyanocinnamate / styrene copolymer: 17% by weight). The obtained film was cut into a 50 mm square and uniaxially stretched 1.3 times at 140 ° C. (thickness after stretching: 40 μm).

  The total optical transmittance, haze, retardation characteristics, and wavelength dispersion characteristics of the obtained optical compensation film were measured. The results are shown in Table 1.

  The obtained optical compensation film has high light transmittance, excellent transparency, small haze, in-plane retardation (Re), wavelength dispersion characteristics (Re (450) / Re (550)), and Nz coefficient. It has the optical characteristic to do.

Example 2
1.5 g of 4-carboxybenzalmalononitrile / 1-vinylindole copolymer obtained in Synthesis Example 2, cellulose acetate butyrate (molecular weight Mn = 72,000, acetyl group = 15 mol%, butyryl group = 70 mol%, total substitution degree DS = 2.55) 10 g was dissolved in a toluene / methyl ethyl ketone = 6/4 (weight ratio) solution to give a 15 wt% resin solution, and polyethylene terephthalate was coated by a coater. After flowing on the film and drying in two stages at a drying temperature of 40 ° C. and 150 ° C., a film having a width of 150 mm was obtained (ethylcellulose: 87 wt%, 4-carboxybenzalmalononitrile / 1-vinylindole copolymer) Combined: 13% by weight). The obtained film was cut into a 50 mm square and uniaxially stretched 1.8 times at 140 ° C. (thickness after stretching 80 μm).

  The total optical transmittance, haze, retardation characteristics, and wavelength dispersion characteristics of the obtained optical compensation film were measured. The results are also shown in Table 1.

  The obtained optical compensation film has high light transmittance, excellent transparency, small haze, in-plane retardation (Re), wavelength dispersion characteristics (Re (450) / Re (550)), and Nz coefficient. It has the optical characteristic to do.

Example 3
1.5 g of ethyl 4-hydroxy-α-cyanocinnamate / 9-vinylcarbazole obtained in Synthesis Example 3 and ethyl cellulose (ETHOCEL standard manufactured by Dow Chemical Co., Ltd.) as a resin having positive intrinsic birefringence ) 100, molecular weight Mn = 55,000, molecular weight Mw = 176,000, Mw / Mn = 3.2, total substitution degree DS = 2.5) 10 g in toluene / ethyl acetate = 4/6 (weight ratio) solution A 15% by weight resin solution was dissolved and poured onto a polyethylene terephthalate film with a coater. After drying at a drying temperature of 40 ° C. and two steps at 150 ° C., a film with a width of 150 mm was obtained (ethyl cellulose: 87% by weight) , 4-hydroxy-α-cyanocyanocinnamate / 9-vinylcarbazole copolymer: 13% by weight ). The obtained film was cut into 50 mm squares and uniaxially stretched 1.5 times at 145 ° C. (thickness after stretching: 40 μm).

  The total optical transmittance, haze, retardation characteristics, and wavelength dispersion characteristics of the obtained optical compensation film were measured. The results are also shown in Table 1.

  The obtained optical compensation film has high light transmittance, excellent transparency, small haze, in-plane retardation (Re), wavelength dispersion characteristics (Re (450) / Re (550)), and Nz coefficient. It has the optical characteristic to do.

Example 4
2.0 g of 4-hydroxybenzalmalononitrile / 2-vinylnaphthalene copolymer obtained by Synthesis Example 4, ethyl cellulose (ETHOCEL standard 100 manufactured by Dow Chemical Co.) as a resin having positive intrinsic birefringence, 10 g of molecular weight Mn = 55,000, molecular weight Mw = 176,000, Mw / Mn = 3.2, total substitution degree DS = 2.5) was dissolved in a toluene / ethyl acetate = 4/6 (weight ratio) solution. A 15% by weight resin solution was poured on a polyethylene terephthalate film with a coater and dried in two stages at a drying temperature of 40 ° C. and then at 150 ° C. to obtain a film having a width of 150 mm (ethyl cellulose: 83% by weight, 4- Hydroxybenzalmalononitrile / 2-vinylnaphthalene copolymer: 17% by weight). The obtained film was cut into a 50 mm square and uniaxially stretched 1.3 times at 140 ° C. (thickness after stretching: 40 μm).

  The total optical transmittance, haze, retardation characteristics, and wavelength dispersion characteristics of the obtained optical compensation film were measured. The results are also shown in Table 1.

  The obtained optical compensation film has high light transmittance, excellent transparency, small haze, in-plane retardation (Re), wavelength dispersion characteristics (Re (450) / Re (550)), and Nz coefficient. It has the optical characteristic to do.

Example 5
2.0 g of 4-hydroxy-α-cyanocyanocinnamate / N-vinylsuccinimide copolymer obtained in Synthesis Example 5, cellulose acetate propionate (molecular weight Mn = 75,000 as a resin having positive intrinsic birefringence) , Acetyl group = 5 mol%, propionyl group = 80 mol%, total substitution degree DS = 2.55) 10 g was dissolved in a toluene / methyl ethyl ketone = 6/4 (weight ratio) solution to obtain a 15 wt% resin solution. After flowing on a polyethylene terephthalate film with a coater and drying in two stages at a drying temperature of 40 ° C. and 150 ° C., a film having a width of 150 mm was obtained (ethylcellulose: 83% by weight, isobutyl 4-hydroxy-α-cyanocinnamate) / N-vinylsuccinimide copolymer: 17% by weight). The obtained film was cut into a 50 mm square and uniaxially stretched 1.7 times at 140 ° C. (thickness after stretching 60 μm).

  The total optical transmittance, haze, retardation characteristics, and wavelength dispersion characteristics of the obtained optical compensation film were measured. The results are also shown in Table 1.

  The obtained optical compensation film has high light transmittance, excellent transparency, small haze, in-plane retardation (Re), wavelength dispersion characteristics (Re (450) / Re (550)), and Nz coefficient. It has the optical characteristic to do.

Example 6
1.5 g of ethyl 3,4-dihydroxy-α-cyanocinnamate / N-vinylphthalimide copolymer obtained in Synthesis Example 6 and ethyl cellulose (Ethocel Standard manufactured by Dow Chemical Co., Ltd.) as a resin having positive intrinsic birefringence ( ETHOCEL standard) 100, molecular weight Mn = 55,000, molecular weight Mw = 176,000, Mw / Mn = 3.2, total substitution degree DS = 2.5) 10 g of toluene / ethyl acetate = 6/4 (weight ratio) A 15% by weight resin solution was dissolved in the solution, poured onto a polyethylene terephthalate film with a coater, dried in two stages at a drying temperature of 40 ° C. and then 150 ° C., and then a film with a width of 150 mm was obtained (ethyl cellulose: 87 % By weight, 3,4-dihydroxy-α-cyanocinnamic acid ethyl / N-vinylphthalimide copolymer : 13% by weight). The obtained film was cut into 50 mm squares and uniaxially stretched 1.5 times at 145 ° C. (thickness after stretching: 40 μm).

  The total optical transmittance, haze, retardation characteristics, and wavelength dispersion characteristics of the obtained optical compensation film were measured. The results are also shown in Table 1.

The obtained optical compensation film has high light transmittance, excellent transparency, small haze, in-plane retardation (Re), wavelength dispersion characteristics (Re (450) / Re (550)), and Nz coefficient. It has the optical characteristic to do.
Example 7
2.0 g of 4-carboxy-3-hydroxybenzalmalononitrile / 2-vinylfuran copolymer obtained according to Synthesis Example 7, ethyl cellulose (ETHOCEL manufactured by Dow Chemical Co., Ltd.) as a resin having positive intrinsic birefringence standard) 100, molecular weight Mn = 55,000, molecular weight Mw = 176,000, Mw / Mn = 3.2, total substitution degree DS = 2.5) 10 g in toluene / ethyl acetate = 6/4 (weight ratio) solution A 15% by weight resin solution was dissolved into a polyethylene terephthalate film by a coater, dried at a drying temperature of 40 ° C. and then dried at 150 ° C. in two steps to obtain a film having a width of 150 mm (ethyl cellulose: 83 wt. %, 4-carboxy-3-hydroxybenzalmalononitrile / 2-vinylfuran copolymer : 17 wt%). The obtained film was cut into 50 mm square and uniaxially stretched 1.2 times at 140 ° C. (thickness after stretching: 40 μm).

  The total optical transmittance, haze, retardation characteristics, and wavelength dispersion characteristics of the obtained optical compensation film were measured. The results are also shown in Table 1.

  The obtained optical compensation film has high light transmittance, excellent transparency, small haze, in-plane retardation (Re), wavelength dispersion characteristics (Re (450) / Re (550)), and Nz coefficient. It has the optical characteristic to do.

Example 8
2.0 g of 4-hydroxy-α-cyanocyanocinnamate / 9-vinylcarbazole copolymer obtained in Synthesis Example 8 and ethyl cellulose (ETHOCEL standard manufactured by Dow Chemical Co., Ltd.) as a resin having positive intrinsic birefringence ) 100, molecular weight Mn = 55,000, molecular weight Mw = 176,000, Mw / Mn = 3.2, total substitution degree DS = 2.5) 10 g in a toluene / ethyl acetate = 6/4 (weight ratio) solution A 15% by weight resin solution was dissolved and poured onto a polyethylene terephthalate film with a coater. After drying at a drying temperature of 40 ° C. and two steps at 150 ° C., a film with a width of 150 mm was obtained (ethyl cellulose: 83% by weight) 4-hydroxy-α-cyanocyanocinnamate / 9-vinylcarbazole copolymer: 1 7% by weight). The obtained film was cut into a 50 mm square and uniaxially stretched 1.5 times at 150 ° C. (thickness after stretching: 40 μm).

  The total optical transmittance, haze, retardation characteristics, and wavelength dispersion characteristics of the obtained optical compensation film were measured. The results are also shown in Table 1.

  The obtained optical compensation film has high light transmittance, excellent transparency, small haze, in-plane retardation (Re), wavelength dispersion characteristics (Re (450) / Re (550)), and Nz coefficient. It has the optical characteristic to do.

Comparative Example 1
Ethyl cellulose (ETHOCEL standard 100 manufactured by Dow Chemical Co., Ltd.), molecular weight Mn = 55,000, molecular weight Mw = 176,000, Mw / Mn = 3.2, total substitution degree DS = 2.5) 10 g with toluene / Dissolve in ethyl acetate = 8/2 (weight ratio) solution to make a 15 wt% resin solution, pour it onto a polyethylene terephthalate film with a coater, and dry it twice at 150 ° C after drying temperature 40 ° C, A 150 mm film was obtained. The obtained film was cut into a 50 mm square and uniaxially stretched 1.5 times at 140 ° C. (thickness after stretching: 40 μm).

  The total optical transmittance, haze, retardation characteristics, and wavelength dispersion characteristics of the obtained optical compensation film were measured. The results are also shown in Table 1.

  The obtained film did not have the desired optical characteristics of the Nz coefficient.

Comparative Example 2
10 g of cellulose acetate butyrate (molecular weight Mn = 72,000, acetyl group = 15 mol%, butyryl group = 70 mol%, total substitution degree DS = 2.55) in a toluene / methyl ethyl ketone = 6/4 (weight ratio) solution A 15% by weight resin solution was dissolved and poured onto a polyethylene terephthalate film with a coater. After drying at a drying temperature of 40 ° C. and then at 150 ° C., a film having a width of 150 mm was obtained. The obtained film was cut into a 50 mm square and uniaxially stretched 1.8 times at 140 ° C. (thickness after stretching 80 μm).

  The total optical transmittance, haze, retardation characteristics, and wavelength dispersion characteristics of the obtained optical compensation film were measured. The results are also shown in Table 1.

  The obtained film did not have the desired optical characteristics of the Nz coefficient.

Comparative Example 3
10 g of the 4-carboxy-α-cyanocyanocinnamate / styrene copolymer obtained in Synthesis Example 1 was dissolved in a toluene / methyl ethyl ketone = 6/4 (weight ratio) solution to form a 20 wt% resin solution. After flowing on a polyethylene terephthalate film and drying twice at 150 ° C. after a drying temperature of 40 ° C., a film having a width of 150 mm was obtained. The obtained film was cut into 50 mm squares and uniaxially stretched 1.1 times at 180 ° C. (thickness after stretching: 15 μm).

  The total optical transmittance, haze, retardation characteristics, and wavelength dispersion characteristics of the obtained optical compensation film were measured. The results are also shown in Table 1.

  The obtained film did not have the optical characteristics intended for the in-plane retardation (Re) and the Nz coefficient.

Comparative Example 4
10% of 4-carboxy-3-hydroxybenzalmalononitrile / 2-vinylfuran copolymer obtained in Synthesis Example 7 was dissolved in a toluene / ethyl acetate = 6/4 (weight ratio) solution to give a 20% by weight resin. The resulting solution was poured onto a polyethylene terephthalate film with a coater and dried in two stages at 150 ° C. after a drying temperature of 40 ° C. to obtain a film having a width of 150 mm. The obtained film was cut into 50 mm squares and uniaxially stretched 1.1 times at 180 ° C. (thickness after stretching: 15 μm).

  The total optical transmittance, haze, retardation characteristics, and wavelength dispersion characteristics of the obtained optical compensation film were measured. The results are also shown in Table 1.

  The obtained film did not have the optical characteristics intended for the in-plane retardation (Re) and the Nz coefficient.

Claims (8)

A resin composition comprising a resin having a residue unit represented by the following general formula (1) and a resin having positive intrinsic birefringence.

(1)
(Here, R ₁ and R ₂ are each independently hydrogen (except when R ₁ and R ₂ are both hydrogen), a cyano group, an ester group (—C (═O) OX ₁ ), An amide group (—C (═O) N (X ₂ ) (X ₃ ) or —NX ₄ C (═O) X ₅ ), or an acyl group (—C (═O) X ₆ ) (where X ₁ ˜X ₆ each independently represents a linear alkyl group having 1 to 12 carbon atoms, a branched alkyl group having 1 to 12 carbon atoms, or a cyclic group having ₃ to 14 carbon atoms. R ₇ is independently hydrogen, a linear alkyl group having 1 to 12 carbon atoms, a branched alkyl group having 1 to 12 carbon atoms, a cyclic group having 3 to 14 carbon atoms, a halogen, a hydroxy group, a carboxy group, or a nitro group. Group, cyano group, thiol group, sulfonic acid group, alkoxy group (—OX ₇ ), ester group (—C (= O) OX ₈ ), sulfonyl group (—SOOX ₉ ), amide group (—C (═O) N (X ₁₀ ) (X ₁₁ ) or —NX ₁₂ C (═O) X ₁₃ ), acyl group (—C (═O) X ₁₄ ), an amino group (—N (X ₁₅ ) (X ₁₆ )), or an acyloxy group (—OC (═O) X ₁₇ ) (where X _{7 to} X ₉ are each independently A linear alkyl group having 1 to 12 carbon atoms, a branched alkyl group having 1 to 12 carbon atoms, or a cyclic group having 3 to 14 carbon atoms, and X _{10 to} X ₁₇ are each independently hydrogen, carbon number A linear alkyl group having 1 to 12, a branched alkyl group having 1 to 12 carbon atoms, or a cyclic group having 3 to 14 carbon atoms.) And R _{3 to} R ₇ are adjacent substituents. And a condensed ring structure may be formed. _2. The resin composition according to claim 1, wherein one of R ₁ and R ₂ is selected from the group consisting of a cyano group, an ester group, an amide group, and an acyl group, and the other is hydrogen or a cyano group. . One of R ₁ and R ₂ is selected from the group consisting of a cyano group, an ester group, an amide group, and an acyl group, the other is a cyano group, and at least one of R _{3 to} R ₇ is a hydroxy group It is one or more hydrogen-bonding substituents selected from the group consisting of a group, a carboxy group, a thiol group, a sulfonic acid group, an ester group, an amide group, an acyl group, an amino group, a sulfonyl group, and an acyloxy group. The resin composition according to claim 1 or 2. The residue unit represented by the general formula (1) is 2-hydroxy-α-cyanocinnamic acid ester residue unit, 3-hydroxy-α-cyanocinnamic acid ester residue unit, 4-hydroxy-α-cyanocinnamic acid ester Residue unit, 2,3-dihydroxy-α-cyanocinnamic acid ester residue unit, 2,4-dihydroxy-α-cyanocinnamic acid ester residue unit, 3,4-dihydroxy-α-cyanocinnamic acid ester residue unit Unit, 2-carboxy-α-cyanocinnamic acid ester residue unit, 3-carboxy-α-cyanocinnamic acid ester residue unit, 4-carboxy-α-cyanocinnamic acid ester residue unit, 2,3-dicarboxy -Α-cyanocinnamic acid ester residue unit, 2,4-dicarboxy-α-cyanocinnamic acid ester residue unit, 3,4-dicarboxy-α-cyanocinnamic acid Ester residue unit,
2-carboxy-3-hydroxy-α-cyanocinnamic acid ester residue unit, 3-carboxy-2-hydroxy-α-cyanocinnamic acid ester residue unit, 3-carboxy-4-hydroxy-α-cyanocinnamic acid ester unit Residue unit, 4-carboxy-3-hydroxy-α-cyanocinnamic acid ester residue unit, 2-carboxy-4-hydroxy-α-cyanocinnamic acid ester residue unit, 4-carboxy-2-hydroxy-α- Cyanocinnamate residue units, 2-hydroxybenzalmalononitrile residue units, 3-hydroxybenzalmalononitrile residue units, 4-hydroxybenzalmalononitrile residue units, 2,3-dihydroxybenzalmalononitrile Residue unit, 2,4-dihydroxybenzalmalononitrile residue unit, 3,4-dihydroxy Nzarmalononitrile residue unit, 2-carboxybenzalmalononitrile residue unit, 3-carboxybenzalmalononitrile residue unit, 4-carboxybenzalmalononitrile residue unit, 2,3-dicarboxybenzalmalono Nitrile residue unit, 2,4-dicarboxybenzalmalononitrile residue unit, 3,4-dicarboxybenzalmalononitrile residue unit, 2-carboxy-3-hydroxy-benzalmalononitrile residue unit, 3 -Carboxy-2-hydroxy-benzalmalononitrile residue unit, 3-carboxy-4-hydroxy-benzalmalononitrile residue unit, 4-carboxy-3-hydroxy-benzalmalononitrile residue unit, 2-carboxy -4-hydroxy-benzalmalononitrile residue unit, 4-carboxy-2- Dorokishi - resin composition according to any one of claims 1 to 3, characterized in that benzal Marono least one selected from the group consisting of nitrile residue unit. The resin having a residue unit represented by the general formula (1) further has a residue unit represented by the following general formula (2) or a residue unit represented by the following general formula (3): The resin composition in any one of Claims 1-4.

(2)
(Here, R ₈ represents hydrogen, a linear alkyl group having 1 to 12 carbon atoms, a branched alkyl group having 1 to 12 carbon atoms, or a cyclic group having 3 to 14 carbon atoms, and R ₉ represents hydrogen or a carboxy group. Or an ester group (—C (═O) OX ₁₈ ), wherein R _{10 to} R ₁₄ are each independently hydrogen, a linear alkyl group having 1 to 12 carbon atoms, or a branched alkyl group having 1 to 12 carbon atoms. , C 3-14 cyclic group, halogen, hydroxy group, carboxy group, nitro group, cyano group, thiol group, sulfonic acid group, alkoxy group (—OX ₁₉ ), ester group (—C (═O) OX ₂₀ ), Sulfonyl group (—SOOX ₂₁ ), amide group (—C (═O) N (X ₂₂ ) (X ₂₃ ) or —NX ₂₄ C (═O) X ₂₅ ), acyl group (—C (═O) X _26), an amino group _{(-N (X 27) (X} 2 )), Or an acyloxy group _{(-OC (= O) X 29} ) ( _wherein, X 18 _{to X 21} are each independently a linear alkyl group having 1 to 12 carbon atoms, branched having 1 to 12 carbon atoms An alkyl group or a cyclic group having 3 to 14 carbon atoms, wherein X _{22 to} X ₂₉ are each independently hydrogen, a linear alkyl group having 1 to 12 carbon atoms, or a branched alkyl group having 1 to 12 carbon atoms. Or a cyclic group having 3 to 14 carbon atoms.) And R _{10 to} R ₁₄ may form a condensed ring structure with adjacent substituents.

(3)
(Here, R ₁₅ represents an m-membered ring heterocyclic residue containing one or more heteroatoms or a 5-membered ring residue containing no heteroatoms, and m represents an integer of 5 to 10. The ring residue and the 5-membered ring residue may form a condensed ring structure.) The resin having the residue unit represented by the general formula (1) further includes a styrene residue unit, a vinylnaphthalene residue unit, a 1-vinylindole residue unit, a 9-vinylcarbazole residue unit, and an N-vinylsuccinimide residue. Unit, N-vinylphthalimide residue unit, 2-vinylfuran residue unit, 2-vinylbenzofuran residue unit, cinnamic acid residue unit, methyl cinnamate residue unit, ethyl cinnamate residue unit, cinnamon Isopropyl cinnamate residue units (and these residue units have one or more residue units selected from the group consisting of hydrogen on the cyclic group may be substituted with any substituent) The resin composition according to any one of claims 1 to 5, wherein: An optical film comprising the resin composition according to any one of claims 1 to 6. An in-plane retardation (Re) represented by the following formula (a) is 50 to 500 nm, using the resin composition according to any one of claims 1 to 6, and represented by the following formula (b). The Nz coefficient is 0 ≦ Nz ≦ 1.0, and the ratio Re (450) / Re (550) of the in-plane retardation (Re) at the light wavelength of 450 nm and the in-plane retardation (Re) at the light wavelength of 550 nm. ) Is 0.60 <Re (450) / Re (550) <1.10.
Re = (nx−ny) × d (a)
Nz = (nx-nz) / (nx-ny) (b)
(Where nx represents the refractive index in the direction of the stretching axis in the film plane, ny represents the refractive index in the direction perpendicular to the stretching axis in the film plane, and nz represents the refractive index outside the film plane (thickness direction). D indicates the film thickness.)