JP2003090917A - Phase contrast film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a phase contrast film having excellent physical characteristics such as transparency, thermal stability and shock resistance and excellent optical characteristic such as photoelastic constant. SOLUTION: The phase contrast film is formed from a copolymer polycarbonate resin or a polycarbonate resin blend consisting of a structural unit (I) expressed by general formula (I) and a structural unit (II) expressed by formula (II) with the proportion of the mole fraction of the structural unit (I) ranging from 15 to 85% to the total of the structural units (I) and (II).

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a retardation film. More specifically, it relates to a retardation film formed from a copolymerized polycarbonate resin or a polycarbonate resin blend.

[0002]

2. Description of the Related Art Polycarbonate resin (hereinafter sometimes referred to as PC) is a polymer in which bisphenol is linked by carbonic acid ester, and among them, 2,2-bis (4-hydroxyphenyl) propane (commonly called bisphenol A). The obtained polycarbonate resin is used in many fields because it has excellent transparency, heat resistance, and mechanical properties such as impact resistance. In the optical field such as various lenses and optical disks, the characteristics such as impact resistance, transparency, and low water absorption have attracted attention and occupy an important position as materials for optical applications.

However, a retardation film formed from a polycarbonate resin obtained by reacting bisphenol A with a carbonate precursor substance such as phosgene or diphenyl carbonate has a large photoelastic constant and a large birefringence of the film. Have.

[0004]

Therefore, a first object of the present invention is to provide a retardation film having excellent transparency, heat resistance and impact resistance. A second object of the present invention is to provide a retardation film having a low photoelastic constant. A third object of the present invention is to provide a retardation film having physical properties and optical properties.

[0005]

Means for Solving the Problems The inventors of the present invention have conducted various studies to solve the above problems, and as a result, have been obtained from a dihydroxy compound component containing cyclohexanedimethanol and a specific bisphenol in a fixed ratio. The inventors have found that a retardation film formed from a copolymerized polycarbonate resin or a polycarbonate resin blend achieves the above-mentioned object of the present invention, and arrived at the present invention.

That is, according to the present invention, the following general formula (I)

[0007]

[Chemical 8]

The structural unit (I) represented by
I)

[0009]

[Chemical 9]

The constitutional unit (II) is represented by the following formula, and the molar ratio of the constitutional unit (I) is the constitutional units (I) and (II).
There is provided a retardation film formed from a copolymerized polycarbonate resin or a polycarbonate resin blend, which is 15 to 85% based on the total of the above.

(However, in the above structural unit (II), R ₁
And R ₂ are each independently a halogen atom and a carbon number of 1
-10 alkyl group, C1-C10 alkoxy group,
Cycloalkyl group having 6 to 20 carbon atoms, cycloalkoxy group having 6 to 20 carbon atoms, aryl group having 6 to 10 carbon atoms, aralkyl group having 7 to 20 carbon atoms, aryloxy group having 6 to 10 carbon atoms or carbon number An aralkyloxy group of 7 to 20, wherein q and r are each an integer of 0 to 4,
W is the following

[0012]

[Chemical 10]

Wherein R ₃ and R ₄ are the same or different and each represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, and R ₅ and R ₆ are each independently a hydrogen atom. Alternatively, an alkyl group having 1 to 3 carbon atoms, p is an integer of 4 to 7, R ₇ and R ₈ are each independently a hydrogen atom, a halogen atom, or an alkyl group having 1 to 3 carbon atoms. )

The retardation film of the present invention is not only excellent in transparency, impact resistance and heat resistance, but also low in photoelastic constant and excellent in stretchability for producing the film.

As far as the present inventor investigated, there are several documents relating to a copolycarbonate resin obtained by polymerizing cyclohexanedimethanol (CHDM) together with bisphenol as a dihydroxy component. The literature is briefly introduced below.

(1) US Pat. No. 4,501,875 (JP-A-59-74121) In this document, dihydric phenol and aliphatic (or alicyclic)
Copolymerized polycarbonate resins having improved processability by reacting the bishaloformate of glycol with phosgene are described. Specifically, the polycarbonate obtained by copolymerizing 4 mol% of bischloroformate of CHDM with bisphenol A has an impact value other than that in which the flowability (melt flow) is improved as compared with the polycarbonate containing bisphenol A alone. It is only described that the same physical properties can be obtained for the deflection temperature under load and the ductility.

(2) Japanese Unexamined Patent Publication No. 63-92642 In this document, bisphenol A and 2 to 4 relative thereto.
It is described that a copolymerized polycarbonate obtained by transesterifying CHDM of mol% with diphenyl carbonate is used as an optical disk substrate.

(3) Japanese Unexamined Patent Publication (Kokai) No. 8-302005. In this document, bisphenol A and CHDM (4 mol%) are polymerized with diphenyl carbonate by a transesterification reaction to obtain a copolymerized polycarbonate. It is described that a polymer having an extremely low proportion of hydroxyl end groups can be obtained by using a large amount and that the polymer has improved hydrolysis resistance.

(4) European Polymer Journal.Vol.12
pp279-282 (1976) In this document, bisphenol A and CHDM are reacted with phosgene in a methylene chloride solvent using pyridine as an acid binder to obtain a copolycarbonate by homogeneous solution polymerization. 1 to 50 mol% CHDM
To obtain a copolycarbonate containing at a ratio of
The results of measuring the molecular weight and the physical properties (tensile stress, elongation at break) by the GPC method are described.
Uses of the obtained copolycarbonate in this document,
In particular, nothing is mentioned about optical applications.

(5) Polymer, 1983, Vol. 24, October pp13
13-1316 In this document, 50/5 of bisphenol A and CHDM
0 (molar ratio) of alternating copolycarbonate, which is obtained by homogenous solution polymerization of chloroformate of bisphenol A and CHDM in methylene chloride solvent using pyridine as an acid binder. The results of measurement of physical properties (viscosity, glass transition point, aging characteristics) are described in order to compare this polycarbonate with a random copolymerized polycarbonate. In this document, there is no description about the use of the alternating copolycarbonate, particularly the optical use.

The retardation film of the present invention will be described in more detail below. The copolymerized polycarbonate resin or polycarbonate resin blend that forms the retardation film of the present invention is composed of the following structural units (I) and (II) as described above, and the ratio of the structural unit (I) is a molar fraction, 15 to 8 relative to the total of structural units (I) and (II)
It is 5%, preferably 30 to 85%.

[0022]

[Chemical 11]

(In the formula, the definitions of R ₁ , R ₂ , W, q and r are the same as the definition of the structural unit (II).)

The above structural units (I) and (II) are represented by the following formula (II-R) and cyclohexanedimethanol represented by the following formula (I-R) as dihydroxy compound components in the production of a polycarbonate resin. Is a unit formed by using a bisphenol.

[0025]

[Chemical 12]

(However, in the formula (II-R), R ₁ , R ₂ , W,
The definitions of q and r are the same as the definition of the structural unit (II). )

In the present invention, the molar ratio of the structural unit (I) is 15 with respect to the total of the structural units (I) and (II).
The copolymerized polycarbonate resin or the polycarbonate resin blend which is up to 85% is, in short, in the entire resin used as the retardation film, whether it is a copolymer or a blend of the polycarbonate resins,
The molar ratio of the structural unit (I) is the structural unit (I) and
It means that the content may be 15 to 85% with respect to the total of (II). This ratio can be analyzed by, for example, NMR. That is, it means that a blended product or a copolymer may be used in producing the retardation film. The blended product may be a copolymer, a copolymer and a homopolymer, or a homopolymer. However, in the case of a blend, it is preferable that the blends are compatible with each other from the viewpoints of optical properties and transparency.

Specific examples of the blended product include, for example, a blended product of (i) a homopolycarbonate resin composed of the structural unit (I) and a homopolycarbonate resin composed of the structural unit (II), and (ii) a structural unit (I). A blend of a homopolycarbonate resin consisting of the structural unit (I) and a carbonate copolymer resin consisting of the structural units (II), (iii) a homopolycarbonate resin consisting of the structural unit (II), and structural units (I) and (II) (Iv) a homopolycarbonate resin composed of the structural unit (I), a homopolycarbonate resin composed of the structural unit (II), and a carbonate composed of the structural units (I) and (II) Three types of blends with copolymer resins are mentioned. These blends are mere examples, and slight modifications and additions thereof are permissible unless the gist of the present invention is changed. In particular, in the above (i) to (iv), the composition of the "carbonate copolymer resin" does not have to be the same as that of the above-mentioned "copolymerized polycarbonate resin". That is, in the "carbonate copolymer resin", the ratio of the mole fraction of the structural unit (I) is, for example, 5 to 95%, preferably 10 to 90% with respect to the total of the structural units (I) and (II).
Can be%.

However, the retardation film of the present invention is preferably formed of a copolymerized polycarbonate resin rather than a polycarbonate resin blend from the viewpoints of optical properties and transparency.

Next, specific compounds of cyclohexanedimethanol (IR) and bisphenol (II-R) as dihydroxy compounds used in the production of the copolymerized polycarbonate resin or the polycarbonate resin blend of the present invention will be described. Will be explained.

The cyclohexanedimethanol represented by the above formula (IR) may be a cis isomer, a trans isomer or a mixture of cis / trans isomers, 1,2-cyclohexanedimethanol and 1,3-cyclohexanedimethanol. 1,4-cyclohexanedimethanol may be mentioned. Of these, 1,4-cyclohexanedimethanol is preferable. These may be used alone or in combination of two or more.

1,4 as cyclohexanedimethanol
Preference is given to using cyclohexanedimethanol and having a trans / cis ratio in the range 100/0 to 50/50. A more preferable trans / cis ratio is 100/0 to 60/40, and further preferably 10
0/0 to 70/30, most preferably 100/0 to 80 /
Twenty. The higher the trans isomer ratio, the higher the glass transition temperature (Tg) of the copolymerized polycarbonate resin or the polycarbonate resin blend obtained, and the higher the heat resistance. That is, in the case of a copolymerized polycarbonate resin having a molar ratio of 1,4-cyclohexanedimethanol / bisphenol A of 50/50, the trans / cis ratio of 1,4-cyclohexanedimethanol is 50/50.
And 99/1, the glass transition temperature (Tg) of the resin is 89 ° C. and 96 ° C., respectively. In order to obtain 1,4-cyclohexanedimethanol having the highest trans / cis ratio, a method known per se can be adopted. For example, by repeating recrystallization in an organic solvent, 1,4-cyclohexanedimethanol having a high trans isomer ratio can be obtained.

On the other hand, as the bisphenol represented by the formula (II-R), W is

[0034]

[Chemical 13]

(Wherein R ₃ , R ₄ , R ₅ , R ₆ , R ₇ , R ₈ and p have the same definitions as those of the structural unit (II)) are preferred. . Specific examples of bisphenol include, for example, 4,4′-dihydroxybiphenyl, bis (4-hydroxyphenyl) methane, 1,1-
Bis (4-hydroxyphenyl) ethane, 1,1-bis (4-hydroxyphenyl) -1-phenylethane,
2,2-bis (4-hydroxyphenyl) propane, 2,
2-bis (3-methyl-4-hydroxyphenyl) propane, 1,1-bis (4-hydroxyphenyl) cyclohexane, 1,1-bis (4-hydroxyphenyl)-
3,3,5-trimethylcyclohexane, 2,2-bis (3-phenyl-4-hydroxyphenyl) propane,
2,2-bis (3-isopropyl-4-hydroxyphenyl) propane, 2,2-bis (3-t-butyl-4-)
Hydroxyphenyl) propane, 2,2-bis (4-hydroxyphenyl) butane, 2,2-bis (4-hydroxyphenyl) octane, 2,2-bis (3-bromo-)
4-hydroxyphenyl) propane, 2,2-bis (4
-Hydroxy-3,5-dibromophenyl) propane,
2,2-bis (4-hydroxy-3,5-dichlorophenyl) propane, 2,2-bis (4-hydroxy-3,5-
Dimethylphenyl) propane, 2,2-bis (3-cyclohexyl-4-hydroxyphenyl) propane, 1,
1-bis (3-cyclohexyl-4-hydroxyphenyl) cyclohexane, bis (4-hydroxyphenyl)
Diphenylmethane, 9,9-bis (4-hydroxyphenyl) fluorene, 9,9-bis (4-hydroxy-3)
-Methylphenyl) fluorene, 1,1-bis (4-hydroxyphenyl) cyclopentane, 4,4'-dihydroxydiphenylether, 4,4'-dihydroxy-
3,3'-dimethyldiphenyl ether, 4,4'-dihydroxydiphenyl sulfone, 4,4'-dihydroxydiphenyl sulfoxide, 4,4'-dihydroxydiphenyl sulfide, 3,3'-dimethyl-4,4'- Dihydroxydiphenyl sulfide, 3,3'-dimethyl-
4,4'-dihydroxydiphenyl sulfoxide, 3,
3'-dimethyl-4,4'-dihydroxydiphenyl sulfone, 4,4'-dihydroxy-3,3'-diphenyl sulfide, 4,4'-dihydroxy-3,3'-diphenyl sulfoxide, 4,4'-dihydroxy -3,3'-
Diphenyl sulfone, 1,3-bis {2- (4-hydroxyphenyl) propyl} benzene, 1,4-bis {2
Examples include-(4-hydroxyphenyl) propyl} benzene and the like. Among them, 1,1-bis (4-hydroxyphenyl) -1-phenylethane, 2,2-bis (4-hydroxyphenyl) propane, 2,2-bis (3-methyl-4-hydroxyphenyl) propane, 2 , 2-bis (4-hydroxy-3,5-dibromophenyl) propane, 1,1-bis (4-hydroxyphenyl) cyclohexane, 1,1-bis (4-hydroxyphenyl) -3,
3,5-Trimethylcyclohexane, 4,4'-dihydroxydiphenyl sulfone, 3,3'-dimethyl-4,4 '
-Dihydroxydiphenyl sulfone, 9,9-bis (4
-Hydroxy-3-methylphenyl) fluorene, 1,
3-bis {2- (4-hydroxyphenyl) propyl}
Benzene, 1,4-bis {2- (4-hydroxyphenyl) propyl} benzene is preferred, and 2,2-bis (4-hydroxyphenyl) propane, 1,1-bis (4-hydroxyphenyl) cyclohexane, 1 , 1-
Bis (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane, 4,4'-dihydroxydiphenyl sulfone and 9,9-bis (4-hydroxy-3-methylphenyl) fluorene are preferred, and especially 2,2 -Bis (4-hydroxyphenyl) propane [commonly called bisphenol A] or 1,1-bis (4-hydroxyphenyl) cyclohexane is preferred. These may be used alone or in combination of two or more.

The copolymerized polycarbonate resin or the polycarbonate resin blend of the present invention has a molar fraction of the structural unit represented by the general formula (I) when the total molar fraction of all the structural units is 100 mol%. It is 15 to 85%, more preferably 30 to 85%. When the mole fraction of the structural unit (I) exceeds 85%, heat resistance may be deteriorated, which is not preferable as a film material.

The copolymerization polycarbonate resin or the polycarbonate resin blend for use in the retardation film of the present invention has a relatively low degree of polymerization in view of processability and optical properties. That is, in terms of specific viscosity, the range of 0.3 to 2.0 is suitable, and the range of 0.3 to 0.0.
The range of 7 is more preferable. The copolymerized polycarbonate resin or the polycarbonate resin blend having a specific viscosity in this range has excellent fluidity (Q value) as described below,
The stretched film-forming property is excellent, and the resulting film has very little optical distortion.

The copolymerized polycarbonate resin or the polycarbonate resin blend which forms the retardation film of the present invention has a preferable embodiment in its end group and molecular weight distribution. The copolymerized polycarbonate resin or the polycarbonate resin blend is a phenolic hydroxyl group (O) derived from bisphenol which is a raw material monomer.
H group). The content ratio of the terminal groups of the phenolic hydroxyl group (OH group) is 1 to 8 per all the terminal groups.
Advantageously, it is in the range 0 mol%, preferably in the range 2 to 70 mol%. The copolymerized polycarbonate resin or the polycarbonate resin blend is substantially composed of an end group of a phenolic hydroxyl group and an aryl or alkyl end group (for example, a phenyl group, a substituted phenyl group, a methyl group or an ethyl group) having no phenolic hydroxyl group. Has been formed. Therefore, the total amount of the terminal groups of the phenolic hydroxyl group and the aryl group or alkyl group is substantially meant as all the terminal groups.

Therefore, in the present invention, a copolymerized polycarbonate resin or a polycarbonate resin blend having a proportion of phenolic terminal groups of 1 to 80 mol% based on the total amount of 100 mol% is used.

On the other hand, the copolymerized polycarbonate resin or the polycarbonate resin blend of the present invention preferably has a certain range of molecular weight distribution. The weight average molecular weight (Mw) / number average molecular weight (M
n) expressed as a ratio (Mw / Mn) of 1.1 to 3,
Copolymerized polycarbonate resins or polycarbonate resin blends, preferably in the range 1.3 to 2.8, are advantageously utilized. The weight average molecular weight (Mw) and the number average molecular weight (Mn) are determined based on the measuring method described later.

The copolymerized polycarbonate resin or polycarbonate resin blend having the above-mentioned terminal group and molecular weight distribution is a resin obtained by polymerizing by a transesterification method using a carbonate ester (particularly diphenyl carbonate) as a carbonate precursor, as described later. Can be obtained by controlling the charging ratio of carbonate ester and the reaction conditions.

The copolymerized polycarbonate resin or polycarbonate resin blend having the above-mentioned terminal groups and molecular weight distribution has excellent moldability as a film, and the obtained film has good heat resistance, impact resistance and hue, In addition, when the surface of the film is hard-coated to form a hardened layer, the processability of the treatment is facilitated, and it serves to form a hardened layer that is uniformly and firmly adhered.

Next, a polymerization method for producing the copolymerized polycarbonate resin or the polycarbonate resin blend of the present invention will be described.

The copolymerized carbonate resin or polycarbonate resin blend of the present invention uses cyclohexanedimethanol represented by the following formula (I-R) and bisphenol represented by the following formula (II-R) as the main dihydroxy compound. It is manufactured by

[0045]

[Chemical 14]

(However, in the formula (II-R), R ₁ , R ₂ , W,
The definitions of q and r are the same as the definition of the structural unit (II). )

Polymerization methods include a method of reacting the two dihydroxy compounds with phosgene in the presence of an acid binder (solution polymerization method) and a method of transesterifying the two dihydroxy compounds with a carbonate ester (ester). The exchange method) is preferably adopted.

Of these, the transesterification method is advantageous. The transesterification method is not particularly limited in its polymerization form or method. For example, either the melt polymerization method or the solid phase polymerization method can be adopted, but the melt polymerization method is industrially desirable.

In the solution polymerization method, aromatic tertiary amines such as pyridine, quinoline, isoquinoline and dimethylaniline can be used as the acid binder, and pyridine is particularly preferably used. The reaction is carried out in a solution by diluting the acid binder alone or with an organic solvent. As the organic solvent, hydrocarbons such as benzene, toluene and xylene, or halogenated hydrocarbons such as methylene chloride, chloroform, dichloroethane, chlorobenzene and dichlorobenzene are used, and particularly methylene chloride, chloroform, dichloroethane, chlorobenzene and dichlorobenzene. The halogenated hydrocarbons are preferred, with methylene chloride being most preferred. The amount of the acid binder used is usually 2 to 100 molar equivalents, preferably 2 to 50 molar equivalents, relative to phosgene. The reaction temperature is usually 0
It is carried out at 100 ° C, preferably 0-40 ° C. The reaction time is usually several minutes to several days, preferably 10 minutes to 5 hours. Further, monofunctional phenols can be used as the terminal terminator. Monofunctional phenols are commonly used as molecular terminators for molecular weight control, and the resulting polycarbonate resin will be end-capped with groups based on monofunctional phenols. Specific examples of such monofunctional phenols include phenol, p-tert-butylphenol, p-
Examples include cumyl phenol and isooctyl phenol. As other monofunctional phenols, phenols or benzoic acid chlorides having a long-chain alkyl group or an aliphatic polyester group as a substituent,
Alternatively, long-chain alkylcarboxylic acid chlorides can be used.

It is desirable that these terminal terminators are introduced into at least 5 mol%, preferably at least 10 mol% of the terminals of the obtained polycarbonate resin, and the terminator may be used alone or. You may mix and use 2 or more types.

The melt polymerization method by the transesterification method is carried out by mixing the dihydroxy compound and the carbonate ester while heating in the presence of an inert gas to distill the alcohol or phenol to be produced. The reaction temperature varies depending on the boiling point of the alcohol or phenol to be produced, but is usually in the range of 120 to 350 ° C. In the latter stage of the reaction, the pressure of the reaction system is reduced to about 1,330 to 13.3 Pa to facilitate the distillation of the produced alcohol or phenol. The reaction time is usually about 1 to 10 hours.

Examples of the carbonate ester include an optionally substituted ester such as an aryl group having 6 to 12 carbon atoms, an aralkyl group or an alkyl group having 1 to 4 carbon atoms. Specific examples include diphenyl carbonate, bis (chlorophenyl) carbonate, dinaphthyl carbonate, bis (diphenyl) carbonate, dimethyl carbonate, diethyl carbonate, dibutyl carbonate and the like, with diphenyl carbonate being preferred.

The carbonate ester is preferably used in a ratio of 0.97 to 1.2 mol per mol of the dihydroxy compound, particularly preferably in a ratio of 1.0 to 1.1 mol. .

In the transesterification method, a polymerization catalyst can be used to accelerate the polymerization rate. Examples of the polymerization catalyst include alkali such as sodium hydroxide, potassium hydroxide, sodium salt of dihydric phenol and potassium salt. Metal compounds; alkaline earth metal compounds such as calcium hydroxide, barium hydroxide, magnesium hydroxide;
Nitrogen-containing basic compounds such as tetramethylammonium hydroxide, tetraethylammonium hydroxide, trimethylamine and triethylamine; alkoxides of alkali metals and alkaline earth metals; organic acid salts of alkali metals and alkaline earth metals; zinc compounds; boron Compounds; Aluminum compounds; Silicon compounds; Germanium compounds; Organotin compounds; Lead compounds; Osmium compounds; Antimony compounds; Manganese compounds; Titanium compounds; Zirconium compounds, etc. The catalyst used in the transesterification reaction can be used. The catalyst may be used alone or in combination of two or more kinds. The amount of these polymerization catalysts used is preferably in the range of 1 × 10 ⁻⁹ to 1 × 10 ⁻² equivalent, and more preferably 1 × 10 ^{−8 to} 5 × 10 ⁻³ equivalent, relative to 1 mol of the starting dihydroxy compound. Is selected in.
Further, if necessary, a molecular weight modifier, an antioxidant, etc. may be added.

A catalyst deactivator may be added to the obtained polycarbonate resin. As the catalyst deactivator, known catalyst deactivators are effectively used. Among them, ammonium salts of sulfonic acids, phosphonium salts are preferable, and dodecylbenzenesulfonic acid tetrabutylphosphonium salts and the like dodecylbenzenesulfonic acid The above salts and the above salts of paratoluenesulfonic acid such as tetrabutylammonium paratoluenesulfonic acid salt are preferred. In addition, methyl benzene sulfonate as ester of sulfonic acid,
Ethyl benzene sulfonate, butyl benzene sulfonate, octyl benzene sulfonate, phenyl benzene sulfonate, methyl paratoluene sulfonate, ethyl paratoluene sulfonate, butyl paratoluene sulfonate,
Octyl paratoluenesulfonate, phenyl paratoluenesulfonate and the like are preferably used, and among them, dodecylbenzenesulfonic acid tetrabutylphosphonium salt is most preferably used.

The amount of these catalyst deactivators to be used is 0.5 to 50 mol, preferably 0.5 to 50 mol, per 1 mol of the polymerization catalyst selected from alkali metal compounds and / or alkaline earth metal compounds. It can be used in a proportion of 10 mol, more preferably in a proportion of 0.8 to 5 mol.

According to the studies conducted by the present inventors, the copolymerized polycarbonate resin of the present invention has physical properties obtained by the polymerization method, particularly glass transition temperature and fluidity (Q value).
It turns out that there is a slight difference. It is considered that this difference is due to the difference in the ratio of the structural unit (I) and the structural unit (II) alternately arranged on the polymer main chain as described later.

That is, the copolymerized polycarbonate resin of the present invention has a structural unit (I) and a structural unit on both sides of (I) with a carbonate bond (-O-CO-O-) as the center.
(II) bonded structure (hereinafter referred to as "heterocarbonate") and (II) two structural units (I) bonded on both sides or two structural units (II) bonded (hereinafter "homocarbonate") 2) carbonate bond.

The units derived from 1,4-cyclohexanedimethanol as the structural unit (I) and the units derived from bisphenol A as the structural unit (II) will be described by way of example. The heterocarbonate (C-1) and the homocarbonate (C-2 and C-3) are represented by the following chemical structural formulas.

Heterocarbonate

[0061]

[Chemical 15]

Homocarbonate

[0063]

[Chemical 16]

In the production of the copolycarbonate resin, 1,4-cyclohexanedimethanol and bisphenol A were 50/50 as dihydroxy compounds.
When used in a proportion of (mol%), assuming that the reaction proceeds completely stochastically, the heterocarbonate (C
The ratio of -1): homocarbonate (C-2): homocarbonate (C-3) is 50:25:25. That is, in the calculation, the ratio of heterocarbonate (C-1): homocarbonate (C-2 + C-3) is 50:50.

However, according to experiments conducted by the present inventors, 1,4-cyclohexanedimethanol and bisphenol A were used as dihydroxy compounds in an amount of 50%.
When a copolycarbonate resin is produced by using a ratio of / 50 (mol%), the obtained resin is heterocarbonate (C-1): homocarbonate (C-2 + C-).
It was found that the ratio of 3) was not necessarily 50:50, and this ratio was slightly deviated depending on the polymerization method.

According to the solution polymerization method using an aromatic tertiary amine such as pyridine as the acid binder and phosgene as the carbonate precursor, the ratio of heterocarbonate: homocarbonate is, for example, 44:56.
A copolymerized polycarbonate resin in which the ratio of the heterocarbonate is close to the stochastic value like the ratio of is obtained. On the other hand, according to the melt polymerization method using a carbonate ester (for example, diphenyl carbonate) as a carbonate precursor, the ratio of heterocarbonate: homocarbonate is
A copolycarbonate resin is obtained in which the proportion of heterocarbonates is considerably higher than 50 mol%, for example 70:30. The examples of the solution polymerization method and the melt polymerization method are shown as an example in which 1,4-cyclohexanedimethanol and bisphenol A are used at a ratio of 50/50 (mol%) as the dihydroxy compound. As will be apparent from the examples described below, the ratio of the heterocarbonate and the homocarbonate naturally changes depending on the ratio of the cyclohexanedimethanol and the bisphenol used, but if the ratio of the dihydroxy compound used is the same, compared to the solution polymerization method. It was found that a copolycarbonate having a high proportion of heterocarbonate can be obtained by the melt polymerization method.

That is, according to the present invention, when the molar ratio of the structural unit (I): structural unit (II) is m: n (provided that the sum of m and n is 1), the heterocarbonate A copolymerized polycarbonate resin having a content ratio of (2.05 × m × n) or more, preferably (2.1 × m × n) or more can be obtained. In other words, the content ratio of the heterocarbonate means a ratio of carbonate bonds in which the structural unit (I) and the structural unit (II) are alternately arranged in the polymer main chain, and the total carbonate bond (m + n) is 1. It is the ratio when doing.

As described above, the copolymerized polycarbonate resin having a heterocarbonate content ratio of (2.05 × m × n) or more has a molar ratio of the structural unit (I) determined by the melt polymerization method. It is obtained in the range of 15 to 85 mol% based on the total of I) and the structural unit (II). Heterocarbonate content ratio is (2.05 × m × n) or more,
Particularly, the copolymerized polycarbonate resin of (2.1 × m × n) or more has almost the same photoelastic constant as the resin of less than that, but the fluidity (Q value) is high in the content ratio of the heterocarbonate. The better it gets, the better.

The copolymerized polycarbonate resin or the polycarbonate resin blend of the present invention comprises the structural unit (I)
And a structural unit (II), and it has been found that a film having further improved optical properties and heat resistance can be obtained by using a combination of two types of specific types among the structural unit (II). Was done. Two types of structural units of this specific type of unit are represented by the following (II-a) and (II-b).
(II-a) is a structural unit derived by using bisphenol A as bisphenol.

Structural unit (II-a)

[0071]

[Chemical 17]

Structural Unit (II-b) The structural unit (II-b) is represented by the following (II-b-1) and (II-b).
b-2) selected from the group consisting of (II-b-1)
Units are more preferred.

[0073]

[Chemical 18]

However, the units (II-b-1) and (II
In -b-2), R ₁ and R ₂ are each independently an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a cycloalkyl group having 6 to 20 carbon atoms, and a carbon number 6
To C20 cycloalkoxy group, C6 to C10 aryl group, C7 to C20 aralkyl group, C6 to C10
Or an aryloxy group having 7 to 20 carbon atoms or a halogen atom, q and r are each an integer of 0 to 4, W'is an alicyclic hydrocarbon group having 5 to 12 carbon atoms, or following

[0075]

[Chemical 19]

Wherein R ₃ and R ₄ are the same or different and each represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, x is an integer of 1 to 5, R ₅ and R _{5 6} is each independently a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, p is an integer of 4 to 7, R ₇ and R ₈ are each independently a hydrogen atom, a halogen atom or an alkyl group having 1 to 3 carbon atoms And R ₁₁ and R ₁₂ are each independently an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a cycloalkyl group having 6 to 20 carbon atoms, and 6 to 2 carbon atoms.
A cycloalkoxy group having 0 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, an aryloxy group having 6 to 10 carbon atoms, an aralkyloxy group having 7 to 20 carbon atoms, or a halogen atom, y and z are integers of 1 to 4, respectively.

In the above structural unit (II-b), (II-b-
1) is preferable, and as (II-b-1),
The following are particularly preferred.

[0078]

[Chemical 20]

These (i), (ii), (iii) and (i
The units belonging to (II-b) of v) are (i) 1,1-bis (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane and (i) as dihydroxy compounds, respectively.
i) 4,4'-dihydroxydiphenyl sulfone, (iii)
9,9-bis (4-hydroxy-3-methylphenyl)
It is a constitutional unit derived by using fluorene and (iv) 1,1-bis (4-hydroxyphenyl) cyclohexane.

The copolymerized polycarbonate resin or polycarbonate resin blend obtained by combining the two kinds of the structural units (II) described above has structural units (I), (II-a) and (II
-B). In this case, the molar ratio of the structural unit (I) to the total of the structural unit (I) and the structural unit (II) (the total of II-a and II-b) is 15 to 85%, preferably 20 to 85%. 80% and the structural unit (II-a):
The ratio of the structural unit (II-b) is 1:99 to 9 in molar ratio.
The range is 9: 1, preferably 30:70 to 99: 1, particularly preferably 40:60 to 95: 5, and most preferably 50:50 to 90:10.

By using the two kinds of the structural unit (II) in combination as described above, the glass transition temperature is higher and the photoelastic constant is higher than that when only the structural unit (II) (II-a) is used. The improved copolymerized polycarbonate resin or polycarbonate resin blend and the retardation film are obtained.

The retardation film is preferably made of a copolycarbonate resin rather than a polycarbonate resin blend. A polycarbonate homopolymer having a bisphenol A skeleton, which has been widely used as a retardation film, has a problem that it has a high optical elasticity constant although it has high transparency and heat resistance. For example, among retardation films used for liquid crystal display devices, there are cases where they are used by being attached to a polarizing plate.
In this case, stress is applied to the retardation film due to thermal contraction, thermal expansion, or the like of the polarizing plate, and as a result, phase difference unevenness occurs and the uniformity of image quality cannot be maintained. As a method for solving such a problem, there is a method of using a norbornene-based resin having a small photoelastic constant, but the norbornene resin has a problem of poor stretchability and low productivity. Good stretchability means that there are few breakages, uniform stretching, and the like. In order to be able to stretch uniformly optically, it is preferable that the optical elastic constant is low. In that sense, norbornene resin is good, but when the resin is fragile, there is a problem that breakage easily occurs in the stretching process. It was A preferred optical elastic constant for use in a retardation film is 70 × 10 ⁻⁸ cm ² /
It is N or less. More preferably 60 × 10 ^-8 cm ² / N
Or less, more preferably 50 × 10 ⁻⁸ cm ² / N or less,
Most preferably, it is 40 × 10 ⁻⁸ cm ² / N or less. The glass transition temperature when used for a retardation film is preferably 90 ° C. or higher, more preferably 10 ° C.
The temperature is 0 ° C or higher, more preferably 110 ° C or higher, and most preferably 120 ° C or higher.

When used as a retardation film, the most preferable constitution comprises the constitutional units (I) and (II) described above, and the molar ratio of the constitutional unit (I) is the constitutional unit (I).
And 15 to 85% of the total of (II) and the copolymerized polycarbonate resin or polycarbonate resin blend, W of the structural unit (II) has a fluorene skeleton represented by the following formula.

[0084]

[Chemical 21]

(Here, R ₇ and R ₈ are each independently a hydrogen atom, a halogen atom or an alkyl group having 1 to 3 carbon atoms.)

In the above formula (E), it is particularly preferable that both R ⁷ and R ⁸ are hydrogen atoms. The homopolycarbonate polymer having the repeating unit of the structural unit (I) has positive refractive index anisotropy, while the structural unit (II)
The homopolycarbonate polymer in which W is the above formula (E) has negative refractive index anisotropy. Here, the positive and negative anisotropy of refractive index means that when uniaxially stretched in the vicinity of the glass transition point (Tg ± 10 ° C.), the one having the maximum refractive index in the stretching direction is the positive or the direction orthogonal to the stretching direction. The one having the maximum refractive index is defined as having a negative refractive index anisotropy. WO00 / 26
According to 705, the wavelength dispersion of the retardation of the retardation film can be freely adjusted by blending and / or copolymerizing those having positive and negative refractive index anisotropies each having a specific retardation wavelength dispersion. It has been shown that it is possible to control. Therefore, it is preferable to use the structural unit (II) in which W has the above formula (E) from the viewpoint of controlling the wavelength dispersion of the phase difference. The fact that the wavelength dispersion of retardation can be freely controlled, especially considering the case where this retardation film is used in a liquid crystal display device, can greatly expand the degree of freedom in the optical design of the liquid crystal display device and improve the image quality. It has an effect that it can contribute. Further, those having the fluorene skeleton of the above formula (E) are
It has high heat resistance and low photoelastic constant and can be preferably used as a retardation film. It also has excellent stretchability.

Particularly, the structural unit (I) represented by the general formula (I) and the structural unit (II) in which W in the general formula (II) is represented by the general formula (E) include the structural unit (I) The molar fraction of the compound is 30 to 85 with respect to the total of the structural units (I) and (II).
%, The copolymerized polycarbonate resin or the polycarbonate resin blend is excellent because it makes it possible to produce a retardation film in which the retardation becomes smaller as the wavelength becomes shorter. Further, it is possible to produce a material having negative refractive index anisotropy depending on the ratio. The retardation film having such a property that the retardation becomes smaller as the wavelength becomes shorter can be used as, for example, a broadband λ / 4 plate or a broadband λ / 2 plate.

The copolymerized polycarbonate resin or the polycarbonate resin blend of the present invention may further contain a phosphorus-containing heat stabilizer in order to prevent a decrease in molecular weight and deterioration of hue during molding. Examples of such heat stabilizers include phosphorous acid, phosphoric acid, phosphonous acid, phosphonic acid and esters thereof.

Specifically, triphenyl phosphite,
Tris (nonylphenyl) phosphite, tridecylphosphite, trioctylphosphite, trioctadecylphosphite, didecylmonophenylphosphite, dioctylmonophenylphosphite, diisopropylmonophenylphosphite, monobutyldiphenylphosphite, mono Decyldiphenylphosphite, monooctyldiphenylphosphite, tris (2,4-
Di-tert-butylphenyl) phosphite, bis (2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite, 2,2-methylenebis (4,6-di-tert-butylphenyl)
Octyl phosphite, bis (nonylphenyl) pentaerythritol diphosphite, bis (2,4-di-t
ert-butylphenyl) pentaerythritol diphosphite, distearyl pentaerythritol diphosphite, tributyl phosphate, triethyl phosphate, trimethyl phosphate, triphenyl phosphate, diphenyl monooxoxenyl phosphate, dibutyl phosphate, dioctyl phosphate, diisopropyl phosphate, tetrakis ( 2,4-di-is
o-propylphenyl) -4,4'-biphenylenediphosphonite, tetrakis (2,4-di-n-butylphenyl) -4,4'-biphenylenediphosphonite, tetrakis (2,4-di-tert-) Butylphenyl) -4,
4'-biphenylene diphosphonite, tetrakis (2,
4-di-tert-butylphenyl) -4,3'-biphenylenediphosphonite, tetrakis (2,4-di-t)
ert-Butylphenyl) -3,3'-biphenylenediphosphonite, tetrakis (2,6-di-iso-propylphenyl) -4,4'-biphenylenediphosphonite, tetrakis (2,6-di-n-) Butylphenyl)-
4,4'-biphenylenediphosphonite, tetrakis (2,6-di-tert-butylphenyl) -4,4'-
Biphenylenediphosphonite, tetrakis (2,6-di-tert-butylphenyl) -4,3'-biphenylenediphosphonite, tetrakis (2,6-di-tert)
-Butylphenyl) -3,3'-biphenylenediphosphonite, bis (2,4-di-tert-butylphenyl) -biphenylphosphonite,

Examples thereof include dimethyl benzenephosphonate, diethyl benzenephosphonate and dipropyl benzenephosphonate. Among them, tris (2,4-di-tert-butylphenyl) phosphite, tetrakis (2,4-di-tert-). Butylphenyl) -4,4'-biphenylene diphosphonite and bis (2,4-di-tert-
Butylphenyl) -biphenylphosphonite is preferred.

These heat stabilizers may be used alone or in combination of two or more. The amount of the heat stabilizer used is 0.001 to 100 parts by weight of the copolymerized polycarbonate resin or the polycarbonate resin blend.
0.15 parts by weight is preferred.

Further, in the copolymerized polycarbonate resin or the polycarbonate resin blend of the present invention, a fatty acid ester compound can be used for the purpose of improving the releasability from the mold during molding.

The fatty acid ester has 1 carbon atom.
~ 20 monohydric or polyhydric alcohols and 10-30 carbon atoms
Is preferably a partial ester or a full ester of the saturated fatty acid. Examples of the partial or total ester of monohydric or polyhydric alcohol and saturated fatty acid include stearic acid monoglyceride, stearic acid diglyceride, stearic acid triglyceride, stearic acid monosorbate, behenic acid monoglyceride, pentaerythritol monostearate, pentaerythritol. Tetrastearate, pentaerythritol tetrapelargonate, propylene glycol monostearate, stearyl stearate, palmityl palmitate, butyl stearate, methyl laurate, isopropyl palmitate, biphenyl biphenate, sorbitan monostearate, 2-ethylhexyl stearate. Rate, etc., among them, stearic acid monoglyceride, stearic acid triglyceride, pentaerythrium Tall tetrastearate are preferably used. The amount of the fatty acid ester used is 0.1 parts by weight per 100 parts by weight of the copolymerized polycarbonate resin or the polycarbonate resin blend.
001-0.5 weight part is preferable.

For the purpose of improving weather resistance and blocking harmful ultraviolet rays, an ultraviolet absorber can be further added to the copolymerized polycarbonate resin or the polycarbonate resin blend of the present invention. Examples of the ultraviolet absorber include benzophenone-based ultraviolet absorbers represented by 2,2′-dihydroxy-4-methoxybenzophenone, 2
-(4,6-Diphenyl-1,3,5-triazine-2-
Tri) -based UV absorber represented by yl) -5-hexyloxyphenol, 2- (2H-benzotriazol-2-yl) -4-methylphenol, 2- (2H
-Benzotriazol-2-yl) -4-tert-octylphenol, 2- (2H-benzotriazole-
2-yl) -4,6-bis (1-methyl-1-phenylethyl) phenol, 2- (2H-benzotriazol-2-yl) -4,6-di-tert-pentylphenol, 2- (5 -Chloro-2H-benzotriazole-
2-yl) -4-methyl-6-tert-butylphenol, 2- (5-chloro-2H-benzotriazole-
2-yl) -2,4-tert-butylphenol and 2,2'-methylenebis [6- (2H-benzotriazol-2-yl) -4- (1,1,3,3-tetramethylbutyl) phenol] Examples thereof include benzotriazole-based ultraviolet absorbers, and these may be used alone or in combination of two or more kinds. These UV absorbers
The amount is usually 0.01 to 1 part by weight, preferably 0.05 to 0.8 part by weight, based on 100 parts by weight of the copolymerized polycarbonate resin or the polycarbonate resin blend.

When the copolymerized polycarbonate resin or the polycarbonate resin blend of the present invention is formed into a film, a bluing agent may be added to cancel the yellow tint of the film based on the polycarbonate resin or the ultraviolet absorber. . As the bluing agent, any bluing agent that can be used in polycarbonate resins can be used without any particular problem. Generally, anthraquinone dyes are easily available and preferred.

As a concrete bluing agent, for example, a general name Solvent Violet 13 [CA.No.
(Color index No) 60725; Trade name Bayer's "Macrolex Violet B", Mitsubishi Chemical Co., Ltd. "Dialesin Blue G", Sumitomo Chemical Co., Ltd. "Sumiplast Violet B"], general name S
event Violet31 [CA. No 682
10; Trade name "Mitsubishi Resin Co., Ltd." Dialesin Violet D "], generic name Solvent Violet3
3 [CA. No. 60725; Trademark name Mitsubishi Chemical Corporation]
"Dialesin Blue J", common name Solvent
Blue94 [CA. No. 61500; trade name "Mitsubishi Resin Co., Ltd." Dialesin Blue N "], general name S
solventViolet36 [CA. No. 6821]
0; Trade name Bayer's "Macrolex Violet 3R"], generic name Solvent Blue 97 [Trade name Bayer's "Macrolex Violet R"
R ”] and the common name Solvent Blue 45 [C
A. No 61110; trade name, "Tetrazole Blue RLS" manufactured by Sand Co., Ltd.] is a typical example. These bluing agents are usually added in a proportion of 0.3 × 10 ⁻⁴ to 2 × 10 ⁻⁴ parts by weight per 100 parts by weight of the copolymerized polycarbonate resin or the polycarbonate resin blend.

An antioxidant known in the art may be added to the copolymerized polycarbonate resin or the polycarbonate resin blend of the present invention for the purpose of preventing oxidation.
Examples thereof include phenolic antioxidants, and specifically, for example, triethylene glycol-bis (3- (3-tert-butyl-5-methyl-4-hydroxyphenyl) propionate), 1,6 -Hexanediol-bis (3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate, pentaerythritol-tetrakis (3- (3,5-di-ter)
t-butyl-4-hydroxyphenyl) propionate), octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate, 1,
3,5-trimethyl-2,4,6-tris (3,5-di-t
ert-butyl-4-hydroxybenzyl) benzene,
N, N-hexamethylene bis (3,5-di-tert-butyl-4-hydroxyhydrocinnamide) 3,5-
Di-tert-butyl-4-hydroxybenzylphosphonate diethyl ester, tris (3,5-di-ter
t-Butyl-4-hydroxybenzyl) isocyanurate, 3,9-bis {1,1-dimethyl-2- [β- (3-
tert-Butyl-4-hydroxy-5-methylphenyl) propionyloxy] ethyl} -2,4,8,10-
Tetraoxaspiro (5.5) undecane and the like can be mentioned. The preferred range of addition of these antioxidants is 0.0001 to 0.05 part by weight with respect to 100 parts by weight of the copolymerized polycarbonate resin or the polycarbonate resin blend.

The retardation film of the present invention may have a protective layer such as a hard coat layer, an antireflection coat layer or an antifogging coat layer formed on the surface thereof. These protective layers will be described later.

The hard coat (curing) layer formed on the surface of the retardation film substrate of the present invention is preferably either thermosetting or active energy curable.

Examples of the thermosetting hard coat material include silicone resins such as organopolysiloxane and melamine resins.

Regarding such silicone resins, JP-A-48-056230 and JP-A-49-014535.
No. 08-054501 and No. 08-1
Resins described in Japanese Patent Publication No. 98985 can be used. For example, _a coating composition comprising an organosilicon compound represented by the general formula (R ₁ ) _a (R ₂ ) _b Si (OR ₃ ) _{4- (a + b)} and / or a hydrolyzate thereof is dried and / or heated. It is a hard coat layer obtained by curing. (Here, R ₁ and R ₂ are each independently selected from the group consisting of alkyl group, allyl group, acyl group, halogen group, glycidoxy group, epoxy group, amino group, phenyl group, mercapto group, methacryloxy group and cyano group. R ₃ is an alkyl group having 1 to 10 carbon atoms, an alkoxyalkyl group, an allyl group or an acyl group, and a and b are integers of 0 or 1.) of these organosilicon compounds Specific examples thereof include tetraalkoxysilanes such as methyl silicate, ethyl silicate, n-propyl silicate, iso-propyl silicate, n-butyl silicate, sec-butyl silicate and tert-butyl silicate, or hydrolysates thereof, and methyl trimethoxy. Silane, methyltriethoxysilane, ethyltriethoxysila , Vinyltrimethoxysilane, phenyltrimethoxysilane, .gamma.-chloropropyl trimethoxy silane, .gamma.-mercaptopropyltrimethoxysilane,
γ-methacryloxypropyltrimethoxysilane, γ
-Aminopropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, (3,4-epoxycyclohexyl) methyltrimethoxysilane, (3,4-
Epoxycyclohexyl) ethyltrimethoxysilane,
trialkoxysilane such as γ- (3,4-epoxycyclohexyl) propyltrimethoxysilane or a hydrolyzate thereof, dimethyldimethoxysilane, dimethyldiethoxysilane, phenylmethyldimethoxysilane,
Examples thereof include dimethoxysilane such as γ-glycidoxypropylmethyldimethoxysilane or a hydrolyzate thereof.

These organosilicon compounds may be used alone or in combination of two or more. These organosilicon compounds are preferably used after being hydrolyzed in order to lower the curing temperature and further accelerate the curing. The hydrolysis is preferably carried out in the presence of an inorganic acid such as hydrochloric acid or sulfuric acid or an organic acid such as acetic acid. The degree of hydrolysis can be easily controlled by adjusting the addition amount of the acid used. Further, an organic solvent may be used in order to carry out the hydrolysis uniformly. Examples of these organic solvents include alcohols, ketones, ethers, cellosolves and aromatic hydrocarbons. These solvents may be used alone or in admixture of two or more.

As the melamine resin, a coating composition comprising a melamine resin such as methylated methylol melamine, propylated methylol melamine, butylated methylol melamine or isobutylated methylol melamine and a crosslinking agent and a curing agent is dried and / or heated. It is a hard coat layer obtained by curing.

The above melamine resins may be used alone or in combination of two or more. In addition, a modifier such as an acrylic resin, a polyether resin, a polyester resin, or a silicone resin may be mixed as long as the physical properties are not impaired. Examples of the curing agent include inorganic acids such as hydrochloric acid, sulfuric acid and nitric acid, and organic acids such as acetic acid, oxalic acid, maleic acid and p-toluenesulfonic acid.

Examples of the cross-linking agent include short-chain glycols such as ethylene glycol, diethylene glycol, butanediol and hexanediol, and long-chain glycols such as polyethylene glycol. These may be used alone or in admixture of two or more. Good.

The blending amounts of the curing agent and the cross-linking agent in the melamine-based coating composition are appropriately determined depending on the purpose. The cross-linking agent is a standard that the functional group of the melamine resin and the functional group of the cross-linking agent are equimolar amounts,
It is preferably 10 to 100 parts by weight of the melamine resin.
200 parts by weight, more preferably 20 to 150 parts by weight. Further, the curing agent is preferably 1 to 10 parts by weight, more preferably 2 to 7 parts by weight, based on 100 parts by weight of the melamine resin. Examples of the solvent include alcohol, ketone, ether, cellosolve and aromatic hydrocarbon. These solvents may be used alone or in admixture of two or more.

As the active energy ray-curable hard coat material, JP-A-54-097633 and JP-A-03-
The materials described in JP-A-145602 and JP-A-2000-229384 can be used. Examples thereof include polyfunctional compounds having two or more active energy ray-curable functional groups, and the active energy ray-curable functional group includes an unsaturated group such as a (meth) acryloyl group, a vinyl group or an allyl group. Examples thereof include those having a group having, preferably a (meth) acryloyl group. For example, it is a poly (meth) acrylate composed of a compound having two or more hydroxyl groups such as polyhydric alcohol and (meth) acrylic acid.

Specific examples of the poly (meth) acrylate compound include the following compounds. For example, 1,
4-butanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, cyclohexanedimethanol di (meth) acrylate, polyethylene glycol di (meth) acrylate, glycerol tri (Meth) acrylate, trimethylolpropane tri (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipenta Erythritol hexa (meth) acrylate, tris (2- (meth) acryloyloxyethyl) isocyanurate, bis (2- (meth) acryloyloxyethyl) ) -2-hydroxyl ethyl isocyanurate, tris (2- (meth) acryloyloxypropyl) isocyanurate, bisphenol A dimethacrylate, ethylene oxide-added trimethylolpropane tri (meth) acrylate, ethylene oxide-added pentaerythritol tetra (meth) Examples thereof include acrylates, hexa (meth) acrylate of ethylene oxide-added dipentaerythritol, and hexa (meth) acrylate of caprolactone-added dipentaerythritol.

Preferred are trimethylolpropane-based poly (meth) acrylate, pentaerythritol-based poly (meth) acrylate and isocyanurate-based poly (meth) acrylate.

In addition to the active energy ray-curable functional group, the polyfunctional compound may further include, for example, a hydroxyl group, a carboxyl group, a halogen group, a urethane bond, an ether bond,
It may have various functional groups and bonds such as ester bond, thioether bond, amide bond, and diorganosiloxane bond. In particular, a (meth) acryloyl group-containing compound having a urethane bond (hereinafter sometimes referred to as "acrylic urethane") is preferable.

As the acrylic urethane which is the above polyfunctional compound, a compound (1) having at least two isocyanate groups in one molecule, a compound (2) having at least two hydroxyl groups in one molecule, and Examples thereof include reaction products of a compound (3) having a hydroxyl group and a (meth) acryloyl group.

As the compound (1) having at least two or more isocyanate groups in one molecule, 2,6-tolylene diisocyanate, 2,4-tolylene diisocyanate, diphenylmethane-4,4-diisocyanate,
Dicyclohexylmethane-4,4-diisocyanate,
Hexamethylene diisocyanate, tetramethylene diisocyanate, phenylene diisocyanate, xylylene diisocyanate, tetramethyl xylylene diisocyanate, 1,5-naphthalene diisocyanate, cyclohexane diisocyanate, isophorone diisocyanate and the like can be mentioned.

As the compound (2) having at least two or more hydroxyl groups in one molecule, ethylene glycol, propylene glycol, 1,4-butanediol, 1,6-
Hexanediol, neopentyl glycol, cyclohexanedimethanol, diethylene glycol, trimethylolpropane, pentaerythritol, ditrimethylolpropane, dipentaerythritol, tris (2-
Hydroxyethyl) isocyanurate and other polyhydric alcohols, polyethylene glycol, polypropylene glycol and other polyalkylene glycols, or the above polyhydric alcohols, polyalkylene glycols and polybasic acids (eg, phthalic acid, terephthalic acid, maleic acid, etc.) or anhydrides thereof. Examples thereof include polyester polyols obtained by condensation reaction with substances.

Specific examples of the compound (3) having a hydroxyl group and a (meth) acryloyl group include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate and 4-hydroxybutyl (meth).
Acrylate, 2-hydroxy-3-chloropropyl (meth) acrylate, 4-hydroxycyclohexyl (meth) acrylate, 2-hydroxy-3-phenyloxypropyl (meth) acrylate, pentaerythritol acrylate and the like can be mentioned.

Specific preferred polyfunctional compounds include, as the above-mentioned acrylic urethane, pentaerythritol or its polymer, polypentaerythritol, polyisocyanate, acrylic urethane which is a product of hydroxyalkyl (meth) acrylate, or pentaurethane. Acrylic urethane, which is a reaction product of erythritol or polypentaerythritol, a hydroxyl group-containing poly (meth) acrylate, and polyisocyanate can be used.

Of the active energy rays for curing, a photopolymerization initiator is used when curing with ultraviolet rays (UV). As the photopolymerization initiator, an aryl ketone photopolymerization initiator (for example, acetophenones, benzophenones, benzoins, benzoin ethers, etc.), a sulfur-containing photopolymerization initiator (for example, sulfides,
Thioxanthones), acylphosphine oxide-based photopolymerization initiators, diacylphosphine oxide-based photopolymerization initiators, and other photopolymerization initiators.

The amount of the above photopolymerization initiator is preferably 0.01 to 20 parts by weight, particularly 0.1 to 10 parts by weight, based on 100 parts by weight of the UV-curable polyfunctional compound. Further, an organic solvent may be included for the purpose of adjusting the viscosity to an appropriate value. Examples of the organic solvent include alcohol, ketone, ether, cellosolve, aromatic hydrocarbon and the like. These solvents may be used alone or in admixture of two or more.

Other components may be added to the coating composition, in addition to the above components, as long as the physical properties of the cured film obtained are not impaired. For example, a curing agent to accelerate the reaction, and a particulate inorganic material to match the refractive index with various substrates,
Further, various surfactants may be contained for the purpose of improving wettability during coating and smoothness of the cured film.

In particular, colloidal silica, which is a colloidal dispersion of high molecular weight silicic acid anhydride in an organic solvent such as water and / or alcohol, is preferably used for improving the surface hardness. Colloidal silica has a particle size of 1 to 100 μm
Those in which the silica fine particles are dispersed are preferably used.
Further, colloidal silica is preferably used in the range of 5 to 70% by weight in order to improve the adhesion to the antireflection film.
Further, it is possible to disperse a colorant (dye and pigment) and a filler or to dissolve an organic polymer to color the coating film. Further, an ultraviolet absorber and an antioxidant can be added.

The means for applying the coating composition to the film is not particularly limited, and known methods such as a dip method, a spray method, a spin coating method, a bar coating method, a flow coating method and a roll coating method can be adopted. . From the viewpoint of surface accuracy, the dipping method and the spin coating method are preferably used. The coating composition applied on the film is
The hard coat layer is formed by curing as follows. In the case of a thermosetting hard coat material, it is dried and / or heated after being applied to the film.

The drying and / or heating temperature is 5
It is preferable to carry out in the range of 0 to 200 ° C, particularly preferably in the range of 70 to 150 ° C. Drying and / or heating is performed until the cured film has a sufficient hardness, and the higher the heating temperature is, the shorter the time is, and it may be performed over 0.3 to 5 hours.

In the case of an active energy ray-curable hard coat material, it is applied by irradiation with an active energy ray such as a UV ray, an electron beam or a laser after coating on the film. The active energy ray is not particularly limited, but UV ray is preferable. As a UV ray source, a xenon lamp, a pulse xenon lamp, a low pressure mercury lamp, a high pressure mercury lamp, an ultra high pressure mercury lamp,
A metal halide lamp, a carbon arc lamp, a tungsten lamp, etc. can be used.

For the purpose of enhancing the adhesion between the film and the hard coat layer, it is preferable to pretreat the film before applying the coating composition. For example, acid,
Chemical treatment with alkali, organic solvent, plasma,
Examples include physical treatment with ultraviolet rays, washing treatment with various detergents, and primer treatment with various resins.

The thickness of the hard coat layer cured by the above method is preferably 1 to 50 μm. If the layer thickness exceeds 50 μm, the curing is insufficient and the adhesion with the film is apt to be impaired, and if it is less than 1 μm, the outermost layer formed on this layer cannot exhibit sufficient abrasion resistance and scratch resistance. There is a fear.

If necessary, a single-layer or multi-layer antireflection layer may be formed on the cured layer. As a constituent component of the antireflection layer, a conventionally known component such as an inorganic oxide, a fluoride or a nitride is used. Specific examples include silicon dioxide, silicon monoxide, zirconium oxide, tantalum oxide, yttrium oxide, aluminum oxide, titanium oxide, magnesium fluoride, silicon nitride and the like.
As its forming method, a vacuum vapor deposition method, a sputtering method,
Examples include an ion plating method and an ion beam assist method. By providing this antireflection layer, the antireflection performance is improved. Further, an antifogging layer may be further formed on the cured layer or antireflection layer.

Thus, the retardation film of the present invention can be used in liquid crystal display devices, reflective liquid crystal display devices, organic or inorganic electroluminescence elements, liquid crystal projectors, optical pickup optical systems in optical recording / reproducing devices, touch panels, antireflection films, and the like. It is preferably used in an optical device. Although a polarization conversion element and a polarization beam splitter are used in the liquid crystal projector, these can be used in combination with the retardation film of the present invention. In an optical pickup system, for example, a polarizing beam splitter and a quarter-wave plate having a retardation of a quarter of the retardation film of the present invention are combined to produce an optical pickup having good performance. Is possible. Moreover, a circularly polarizing plate or an elliptically polarizing plate can be formed by combining the retardation film of the present invention with a polarizing plate. The circularly polarizing plate can be suitably used as an antireflection film in an organic electroluminescence element, a touch panel, a plasma display, a CRT, a liquid crystal display device and the like. Among the retardation films of the present invention, if a retardation film having a retardation that becomes smaller as the wavelength becomes shorter is used as the antireflection film, it is possible to suppress the reflectance at a wavelength in a wide band with one film. Have an effect.

A particularly preferred structure for the retardation film has a repeating unit represented by the following formulas (I) and (iii). This structure has suitable properties as a retardation film, such as transparency, high heat resistance, low optical elastic constant, stretchability, and the ability to freely control retardation wavelength dispersion by the ratio of the following repeating units.

[0128]

[Chemical formula 22]

[0129]

[Chemical formula 23]

The copolymerized polycarbonate resin or the polycarbonate resin blend for forming the retardation film has a content ratio of the terminal groups of the phenolic hydroxyl group (OH group) in the range of 1 to 80 mol%, preferably 2 to 100 mol%.
The range of 70 mol% is preferable. Further, the specific viscosity is preferably in the range of 0.3 to 2.0, and more preferably 0.0.
A range of 3 to 0.7 is more advantageous. Further, the molecular weight distribution (Mw / Mn) is in the range of 1.1 to 3, preferably 1.3 to
Those in the range of 2.8 are advantageous.

The thickness of the retardation film is in the range of 1 to 200 μm, preferably 10 to 150 μm, more preferably 15 to 100 μm. As a method for producing the retardation film, a method known per se is used. For example, the film manufacturing method has excellent thickness uniformity,
A method in which gel, fish eyes, scratches, etc. do not occur and a method in which the content of foreign matters is small are preferable, and examples thereof include a solution casting method, a melt extrusion method, and a calendering method. Especially, when a high degree of homogeneity is required, a casting method from a solution is preferably adopted. As the casting method, generally, a casting method in which a solution is extruded from a die, a doctor knife method and the like are preferably used. Examples of the solvent include methylene chloride, chloroform, dioxolane, toluene, dimethylformamide,
Organic solvents such as N-methylpyrrolidone are preferred. These may be one kind or a mixed solvent of two or more kinds. A solution having a solution concentration of 5 to 50% by weight is preferably used. The film forming method is preferably a solution casting method,
As the stretching method, longitudinal uniaxial stretching, lateral uniaxial stretching, multi-stage stretching simultaneous biaxial stretching and the like may be used. Dichloromethane, dioxolane and the like are preferably used as the solvent for the solution casting.

Further, as described above, the retardation film contains an ultraviolet absorber such as phenylsalicylic acid, 2-hydroxybenzophenone or triphenylphosphate,
You may add a bluing agent, antioxidant, etc. for changing a color.

For the retardation film, known plasticizers such as phthalic acid esters such as dimethyl phthalate, diethyl phthalate and dibutyl phthalate, phosphoric acid esters such as tributyl phosphate, aliphatic dibasic esters, glycerin derivatives, glycol derivatives and the like can be used. May be included. At the time of stretching, the organic solvent used for film formation may be left in the film and stretched. The amount of the organic solvent is preferably 1 to 20 wt% based on the polymer solid content. Further, the above-mentioned additives such as a plasticizer and a liquid crystal can change the retardation wavelength dispersion of the retardation film of the present invention, but the addition amount is preferably 10 wt% or less, more preferably 3 wt% or less relative to the polymer solid content. .

It should be noted that the phase difference chromatic dispersion is largely determined by its chemical structure, but it also varies depending on the stretching conditions, blending state and the like. The retardation film of the present invention constitutes a good quarter-wave plate (λ / 4 plate) or a half-wave plate (λ / 2 plate) having a small wavelength dependence, particularly with one polymer orientation film. However, R (550) ≧ 50 nm is desirable for this application, more preferably R (550) ≧ 90 nm, and particularly 100 nm ≦ for use as a λ / 4 plate.
It is desirable that R (550) ≦ 180 nm, and 220 ≦ R (550) ≦ 330 nm for use as a λ / 2 plate.

More generally, in order that the retardation film of the present invention can be used as a wide band λ / 4 plate by itself, the retardation wavelength dispersion is 0.60 <R (450) / R. (550) <0.97 and 1.01 <R (650) / R (550) <1.40 More preferably 0.65 <R (450) / R (550) <0.92 and 1.03 < R (650) / R (550) <1.30 More preferably 0.70 <R (450) / R (550) <0.87 and 1.04 <R (650) / R (550) <1. It is preferably within the range of 25. Further, the retardation film of the present invention may be bonded to a polarizing plate via an adhesive layer or an adhesive layer to form a circularly polarizing plate or an elliptically polarizing plate, or may be coated with any material on the retardation film to have a wet heat resistance. May be improved or solvent resistance may be improved.
Further, antireflection means may be formed on the retardation film of the present invention, and such a film can be used as an optical component, for example, in an optical device of an optical pickup or a projection display device. .

Further, desired optical characteristics may be obtained by using a plurality of retardation films of the present invention. For example, it is possible to form a wideband quarter-wave film by forming a half-wave plate and a quarter-wave plate and bonding them at an appropriate angle, By bonding the wave plates to each other at an appropriate angle, it is possible to form a wide band half wave plate. Also, "Society for
Information Display2001 International Symposium Di
gest of Technical Papers ”, using the film of the present invention in an arrangement as described in p906-909.
It is possible to produce a laminated film having a viewing angle and a wide band property. Further, other retardation film different from the retardation film of the present invention, for example, in the liquid crystal display device together with an optical compensation film made of a polymer liquid crystal, a viewing angle widening film alignment-cured of a discotic liquid crystal, etc. You may use it.

[0137]

The present invention will be further described with reference to the following examples. In the examples, parts and% are parts by weight and% by weight.
Is. Various physical properties were evaluated by the following methods. (1) Specific viscosity It was measured at a concentration of 0.7 g / 100 ml using methylene chloride as a solvent. The measurement temperature was 20 ° C. (2) Refractive index and Abbe number A casting film of polycarbonate resin (thickness 100 μm) was prepared and measured with an Abbe refractometer manufactured by Atago Co. at 25 ° C. using diiodomethane as a contact liquid. (3) Glass transition temperature (Tg) The glass transition temperature (Tg) was measured using DSC2910 manufactured by TA Instruments Japan KK

(4) Photoelastic constant A photoelastic measuring device PA-150 manufactured by Riken Kikai Co., Ltd. was used to measure a 100 μm thick cast film. (5) Total light transmittance Measured with a haze meter NDH2000 manufactured by Nippon Denshoku Co., Ltd. according to ASTM D-1003. (6) Measurement of phase difference (R value) The phase difference R value is the product of the birefringence Δn and the film thickness d, and R = Δ
It is represented by n · d. The cast film of the uniaxially stretched polycarbonate resin was measured with an ellipsometer M-150 manufactured by JASCO Corporation. In the following examples, R (450), R (550), R (650)
Are the phase difference values at the measurement wavelengths 450, 550 and 650 nm, respectively. (7) Solubility test solvent (methylene chloride, tetrahydrofuran) 100 mL
After adding 10 g of polymer to the mixture and stirring for 1 hour with a magnetic stirrer, the solubility was visually confirmed. The judgment criteria are:
Transparent, Δ: partially insoluble, ×: insoluble.

Example 1 1,4-Cyclohexanedimethanol (CHDM) 7
2.0 parts by weight, bisphenol A (BPA) 114 parts by weight, diphenyl carbonate (DPC) 220 parts by weight and tetramethylammonium hydroxide (TMA)
0.18 parts by weight of H) and 8 × 10 ⁻⁴ parts by weight of sodium hydroxide were charged into a reaction tank equipped with a stirrer, a distiller and a depressurizing device, and after nitrogen substitution, they were dissolved at 140 ° C. Thirty
After stirring for a minute, the internal temperature was raised to 180 ° C. and the pressure was gradually reduced to react at 1.33 × 104 Pa for 30 minutes, and the phenol produced was distilled off. Next, the temperature is continuously raised while maintaining the same pressure, and the temperature is maintained at 190 ° C. for 30 minutes, 200 ° C. for 40 minutes, 220
The reaction was carried out by distilling phenol off at 30 ° C. for 30 minutes and at 240 ° C. for 30 minutes. After that, slowly depressurize 24
The temperature was 0 ° C. and 133 Pa or less. After reaching 133 Pa or less, the reaction was carried out under stirring for 4 hours. As a deactivator, after adding 2.3 × 10 ^-2 parts by weight of tetrabutylphosphonium dodecylbenzenesulfonate, 240 ° C. and 1.33 × 10
After stirring at ⁴ Pa for 20 minutes, the mixture was discharged from the bottom of the reaction tank under nitrogen pressure and cut with a pelletizer while cooling in a water tank to obtain pellets. The pellets thus obtained were dissolved in methylene chloride to prepare a solution having a concentration of 40% by weight. This polycarbonate solution was cast on a glass plate at 15 ° C. using an applicator, and methylene chloride was evaporated while gradually raising the temperature, peeled off from the glass plate and further heated to remove methylene chloride to obtain a vertical length of 297 mm, Width 210mm, thickness 1
A 56 μm A4 size film was obtained. This film had excellent transparency and good casting film-forming property. Next, this film was longitudinally uniaxially stretched at 100 ° C. by 150% to obtain a stretched film having a thickness of 127 μm. The stretchability was good. The results of various evaluations of this film are shown in Table 1.

Example 2 The same operation as in Example 1 was carried out except that 101 parts by weight of CHDM and 113 parts by weight of 9,9-bis (4-hydroxy-3-methylphenyl) fluorene (BCF) were used, and the thickness was 120 μm. A4 size film. This film had excellent transparency and good casting film-forming property.
Then, this film was longitudinally uniaxially stretched at 118 ° C. by 200% to obtain a stretched film having a thickness of 90 μm. The stretchability was good. The results of various evaluations of this film are shown in Table 1.

Comparative Example 1 A bisphenol A type polycarbonate resin powder (Panlite C-1400 manufactured by Teijin Chemicals Ltd.) was used for evaluation. This powder was dissolved in methylene chloride to prepare a solution having a concentration of 20% by weight. This polycarbonate solution was cast on a glass plate at 15 ° C. using an applicator, and methylene chloride was evaporated while gradually raising the temperature,
It was peeled from the glass plate and further heated to remove methylene chloride to obtain an A4 size film having a length of 297 mm, a width of 210 mm and a thickness of 100 μm. This film had excellent transparency and good casting film-forming property. Next, this film was longitudinally uniaxially stretched at 160 ° C. by 150%. The results of various evaluations of this film are shown in Table 1.

Example 3 The same operation as in Example 1 was carried out except that 98 parts by weight of CHDM and 121 parts by weight of BCF were used, and A4 having a thickness of 140 μm was used.
It was used as a plate film. This film had excellent transparency and good casting film-forming property. Next, this film was longitudinally uniaxially stretched at 119 ° C. by 200% to obtain a stretched film having a thickness of 105 μm. The stretchability was good.
The results of various evaluations of this film are shown in Table 1.

[0143]

[Table 1]

Example 4 The film produced in Example 3 was incorporated in a single-polarizing plate reflection type liquid crystal display device mounted in "Game Boy Color" which is a portable game machine manufactured by Nintendo Co., Ltd. and evaluated. The structure is, from the observer's side, polarizing plate / retardation film produced in Example 3 / glass substrate / ITO transparent electrode / alignment film / twisted nematic liquid crystal / alignment film / metal electrode / reflection film / glass substrate. The adhesive layer between each layer is omitted. The pieces were attached at an angle such that white display was obtained when the voltage was off, and the tint was visually evaluated. This retardation film functions as a λ / 4 plate. This commercial product uses two polycarbonate films made of a bisphenol A homopolymer having different retardations (substantially one-half wavelength and one-quarter wavelength retardation). It was confirmed that when only one sheet was used, the coloring was small especially in the black display, whereby the contrast was high and the visibility was excellent.

Example 5 The film prepared in Example 2 was placed on a reflective polarizing plate made of cholesteric liquid crystal, and a commercially available backlight /
The color tone was evaluated by the constitution of the cholesteric liquid crystal layer / the film of Example 2 / the polarizing plate. The film of Example 2 has a λ / 4
It functions as a board. The angle formed by the slow axis of the film and the polarization axis of the polarizing plate was set to 45 °. The light emitted from the polarizing plate was in a white state with little coloring.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Miyake             1-2-2 Uchisaiwaicho, Chiyoda-ku, Tokyo             Human Kasei Co., Ltd. (72) Inventor Yoshihiko Imanaka             1-2-2 Uchisaiwaicho, Chiyoda-ku, Tokyo             Human Kasei Co., Ltd. (72) Inventor Akihiko Uchiyama             4-3, Asahigaoka, Hino-shi, Tokyo Teijin             Tokyo Research Center Co., Ltd. F term (reference) 2H049 BA06 BA07 BB44 BB50 BC09                       BC22                 2H091 FA11X FB02 LA02 LA06                       LA12                 4F071 AA50X AA80 AF23 AF29                       AF30 AF35 AF45 AH16 BA02                       BB02 BB07 BC01 BC02                 4J029 AA09 AB01 AB07 AC02 AD09                       AE03 AE04 BB12A BB12B                       BB12C BD06A BD09A BD09B                       BD09C BF21 BH02 DB11                       DB12 DB13 HA01 HC01 HC03                       HC05A

Claims (12)

[Claims] 1. The following general formula (I): The structural unit (I) and the following formula (II) A copolymeric polycarbonate resin or polycarbonate comprising a structural unit (II) represented by the formula (I), wherein the molar ratio of the structural unit (I) is 15 to 85% with respect to the total of the structural units (I) and (II). A retardation film formed from a resin blend. (However, in the above structural unit (II), R ₁
And R ₂ are each independently a halogen atom and a carbon number of 1
-10 alkyl group, C1-C10 alkoxy group,
Cycloalkyl group having 6 to 20 carbon atoms, cycloalkoxy group having 6 to 20 carbon atoms, aryl group having 6 to 10 carbon atoms, aralkyl group having 7 to 20 carbon atoms, aryloxy group having 6 to 10 carbon atoms or carbon number An aralkyloxy group of 7 to 20, wherein q and r are each an integer of 0 to 4,
W is the following [Chemical formula 3] Wherein R ₃ and R ₄ are the same or different and each represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, and R ₅ and R ₆ are each independently a hydrogen atom or a carbon number. An alkyl group of 1 to 3, p is an integer of 4 to 7, R ₇ and R ₈ are each independently a hydrogen atom, a halogen atom or an alkyl group having 1 to 3 carbon atoms. ) 2. The structural unit (I) is the following structural unit (I ′): The retardation film according to claim 1, represented by: 3. The structural unit (II) has the following W: The group represented by the formula (1) or (2), wherein R ₃ , R ₄ , R ₅ , R ₆ , R ₇ , R ₈ and p have the same definition as that of the structural unit (II). Retardation film. 4. The retardation film according to claim 1, wherein W in the structural unit (II) has a fluorene skeleton represented by the following formula (E). [Chemical 6] (Here, R ₇ and R ₈ are each independently a hydrogen atom, a halogen atom or an alkyl group having 1 to 3 carbon atoms.) 5. The structural unit (I) is represented by the structural unit (I ′), and the configuration of two methylene groups bonded to the 1,4-cyclohexylene group in the formula (I ′) is trans / The retardation film according to claim 1, wherein the cis ratio is in the range of 100/0 to 50/50. [Chemical 7] 6. The constitutional unit (I) represented by the general formula (I) and the constitutional unit (II) represented by the formula (II), wherein the molar ratio of the constitutional unit (I) is Structural unit (I)
The retardation film according to any one of claims 1 to 5, which is formed from a copolymerized polycarbonate resin or a polycarbonate resin blend that is 30 to 85% of the total of (II) and (II). 7. The retardation film according to claim 1, wherein the copolymerized polycarbonate resin or the polycarbonate resin blend has a specific viscosity of 0.3 to 2.0. 8. The copolymerized polycarbonate resin or the polycarbonate resin blend has a content ratio of the terminal groups of the phenolic hydroxyl group (OH group) of 1 to 80 based on all the terminal groups.
The retardation film according to any one of claims 1 to 7, which is in a range of mol%. 9. The weight average molecular weight / number average molecular weight ratio (Mw / Mn) of the copolymerized polycarbonate resin or the polycarbonate resin blend is in the range of 1.1 to 3. Retardation film. 10. A copolymerized polycarbonate resin comprising a structural unit (I) represented by the general formula (I) and a structural unit (II) represented by the formula (II).
10. The retardation film according to any one of 9 to 10. 11. An optical device using the retardation film according to any one of claims 1 to 10. 12. A liquid crystal display device using the retardation film according to any one of claims 1 to 10.