JP2003160660A - Polycarbonate resin copolymer and plastic lens - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve a problem associated with existing technology, obtain a polycarbonate resin copolymer excellent in transparency, fluidity and impact resistance, holding good balance between a refractive index and an Abbe's number, having excellent optical properties such as a low photoelastic constant and having good heat resistance and provide a plastic lens formed from the copolymer. <P>SOLUTION: The polycarbonate resin copolymer consists of a certain ratio of an aliphatic diol having a specific structure, an aromatic bisphenol and a bisphenol having a cyclic terpene skeleton. A plastic lens formed from the copolymer is also provided. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention has excellent mechanical properties such as transparency and impact resistance, keeps a good balance between refractive index and Abbe number, has excellent optical properties such as low photoelastic constant, and has excellent heat resistance. The present invention relates to a polycarbonate resin copolymer having good properties. This polycarbonate resin copolymer is used in various fields, for example, plastic optical moldings such as lenses and optical disk substrates, sheet or film applications, and particularly suitable for lenses.

[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 optical fields such as various lenses and optical discs, their properties such as impact resistance, transparency, and low water absorption have attracted attention, and they are used as materials for optical applications.

Until now, inorganic glass has been the mainstream material for spectacle lenses, but now that plastics occupy 80% of spectacle lens materials due to its moldability, light weight and impact resistance. There is. As a plastic material, polydiethylene glycol bisallyl carbonate represented by CR-39 has become the mainstream as an eyeglass material because it has excellent transparency and heat resistance capable of withstanding various treatments. However, since this resin is a thermosetting resin, 15 to 20 is required for cast polymerization in a glass mold.
It has a problem that it takes time and productivity is low, and it has low impact resistance and is insufficient in terms of safety. Further, polydiethylene glycol bisallyl carbonate has a low refractive index of 1.50, and a resin having a higher refractive index is desired.

On the other hand, in order to improve the productivity, it has been attempted to make a spectacle lens by injection molding or injection compression molding with a thermoplastic resin, and spectacle lenses made of polymethylmethacrylate and spectacle lenses made of polycarbonate are commercially available. There is.

Polymethylmethacrylate is a material having small distortion and excellent transparency, but has a low refractive index of 1.49, poor heat resistance, high water absorption, and insufficient impact resistance. .

2,2-bis (4-hydroxyphenyl)
A polycarbonate resin obtained by reacting propane (commonly called bisphenol A) with a carbonate precursor substance such as phosgene or diphenyl carbonate has excellent transparency and heat resistance, and particularly has excellent mechanical properties such as impact resistance. Used for optical lens applications. However, the refractive index of the polycarbonate resin is 1.58.
Although it is as high as 5, the Abbe number is as low as 30, so that the problem of chromatic aberration is likely to occur, and the photoelastic constant is large, and the melt flowability is relatively poor, resulting in a large birefringence of the molded product.

In order to solve such a drawback of the polycarbonate resin, some copolymerized polycarbonate resins of an aromatic dihydroxy compound and an aliphatic diol have been proposed (JP-A-1-66234 and JP-A-10-26234).
-120777, JP-A-11-228683, JP-A-11-349676, and JP-A-2000-
63506). However, these techniques have problems that the refractive index and Abbe number are still low, that moldability and heat resistance are insufficient and a satisfactory molded product cannot be obtained, and that coloring occurs. On the other hand, the following general formula [3] and general formula [4]

[0008]

[Chemical 9]

Several polycarbonate resins containing a structural unit represented by are proposed. JP-A-7-5
3430 and JP-A-8-198791 disclose homopolycarbonate resins represented by the general formulas [3] and [4], and a polycarbonate resin copolymer of the general formula [3] and bisphenol A. Is shown,
It is described that such a polycarbonate resin has a high glass transition temperature.

Further, JP-A-9-68817 describes that the polycarbonate resin is excellent as a binder resin for a photosensitive layer in the production of an electrophotographic photosensitive member.

However, these publications do not describe a polycarbonate resin copolymer composed of the structural units of the above-mentioned general formulas [3] and [4] and an aliphatic diol, and these publications do not. The polycarbonate resin shown cannot sufficiently solve the above-mentioned drawbacks of the conventional polycarbonate resin from bisphenol A as an optical material. In addition, in the Japanese Unexamined Patent Publication No. 6-107780 from the present applicant, the following formula [5]

[0012]

[Chemical 10]

It is described that an aromatic polycarbonate resin having a repeating unit represented by the following as a main repeating unit has a high glass transition temperature and an excellent balance between the refractive index and the Abbe number, and thus is useful for various lens applications. The homopolycarbonate resin of the above formula [5] listed in the examples has a too high glass transition temperature and is poor in fluidity when a lens is obtained by a method such as injection molding,
There is a problem that it is difficult to obtain a lens with little optical distortion.

[0014]

SUMMARY OF THE INVENTION An object of the present invention is to solve the problems associated with the prior art, and is excellent in transparency, fluidity, impact resistance, and balance between the refractive index and the Abbe number. It is an object of the present invention to provide a polycarbonate resin copolymer which is kept good, has excellent optical properties such as a low photoelastic constant, and has good heat resistance.

Another object of the present invention is to provide a plastic lens formed of a polycarbonate resin copolymer having a well-balanced refractive index and Abbe's number, good photoelastic constant, and good heat resistance. In particular, it is to provide a spectacle lens.

[0016]

The present applicant has previously proposed a plastic lens using a copolycarbonate resin having a constitutional unit derived from an aliphatic diol having a specific structure and an aromatic bisphenol. Wish 20
00-249440). As a result of further intensive studies, the present invention has revealed that a polycarbonate resin copolymer in which a constituent unit composed of a bisphenol having a cyclic terpene skeleton in an aliphatic diol having the above-mentioned specific structure and an aromatic bisphenol is contained in a certain proportion The inventors have found that the heat resistance becomes better while maintaining the physical properties, and arrived at the present invention.

That is, according to the present invention, (A) a structural unit represented by the following general formula [1] (structural unit [A]),

[0018]

[Chemical 11]

[In the above formula [1], R ₁ has ₁ carbon atom.
To 50 alkylene groups, alicyclic alkylene groups having 1 to 50 carbon atoms or the following general formula

[0020]

[Chemical 12]

Where R is₂And R₃Are independent
An alkylene group having 1 to 50 carbon atoms, R _FourHas 1 to 1 carbon atoms
0 is an alkyl group, A is a cycloalkyl having 1 to 50 carbon atoms.
Group or tetraoxospiro group, and e and f are
Each is independently selected from 0 and 1, provided that the sum of e and f
Is 1 or more and g is from 0 to A and is replaceable
An integer having a value up to the number of hydrogen atoms. ] (B) A structural unit represented by the following general formula [2] (a structural unit
Position [B]) and

[0022]

[Chemical 13]

(In the above formula [2], R ₅ and R ₆ are each independently a hydrogen atom, a halogen atom, or a carbon number of 1 to 1.
0 alkyl group, C 1-10 alkoxy group, C 6-20 cycloalkyl group, C 6-20 cycloalkoxy group, C 6-10 aryl group, C 7-20 aralkyl Group, an aryloxy group having 6 to 10 carbon atoms, and an aralkyloxy group having 7 to 20 carbon atoms, m and n are each an integer of 0 to 4, and W is

[0024]

[Chemical 14]

Wherein R ₇ and R ₈ are the same or different and each represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, and R ₉ and R ₁₀ each independently represent a hydrogen atom or 1 to ₁₀ carbon atoms. 3 is an alkyl group, p is an integer of 4 to 7, R ₁₁ and R ₁₂ are each independently a hydrogen atom, a halogen atom or an alkyl group having 1 to 3 carbon atoms. (C) At least one selected from the structural unit represented by the following general formula [3] (structural unit [C-1]) and the structural unit represented by the following general formula [4] (structural unit [C-2]). 1
Consists of two building blocks [C],

[0026]

[Chemical 15]

(In the formula, R ₁₃ , R ₁₄ , R ₁₇ and R ₁₈ are each independently a halogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, and an alkyl group having 6 to 20 carbon atoms. Cycloalkyl group, 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 aralkyloxy having 7 to 20 carbon atoms A base, a,
b, c and d are each an integer of 0 to 4, and R ₁₅ and R
₁₆ and R ₁₉ each independently represent an alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 10 carbon atoms, and R ₂₀ and R ₂₁ each independently represent a hydrogen atom or an alkyl group having 1 to 10 carbon atoms. , A C6-20 cycloalkyl group or a C6-10 aryl group. ) Assuming that all the structural units are 100 mol%, (structural unit [A] +
Structural unit [B]): Ratio of structural unit [C] is 99: 1 to 1
70:30 (mol%), the ratio of the structural unit [A] to the structural unit [B] is 85:15 to 15:85 in molar ratio, and the structural unit [C-1] and the structural unit [[ There is provided a polycarbonate resin copolymer having a molar ratio of C-2] of 100: 0 to 50:50.

The present invention will be described in detail below. Examples of the aliphatic diol compound constituting the structural unit [A] represented by the general formula [1] of the present invention include 1,2-propanediol, 1,3-butanediol, 1,4-butanediol, 1, 5-pentanediol, 1,5-hexanediol, 1,6-hexanediol, 2,2-dimethylpropane-1,3-diol, ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, octaethylene glycol, di Propylene glycol, cyclobutanediol, cyclopentanediol, cyclohexanediol, cyclohexanedimethanol, 2,2-bis (4-hydroxycyclohexyl) propane, bicyclohexyl-4,4'-
Diols, tricyclo [5.2.1.0 ^{2, 6]} decane dimethanol, 3,9-bis (2-hydroxy-1,1
Dimethylethyl) -2,4,8,10-tetraoxaspiro (5.5) undecane, decalin dimethanol, norbornane dimethanol, and pentacyclopentadecane dimethanol are preferable.

In particular, cyclohexanedimethanol represented by the following formula [1-a], tricyclo [5.2.1.0 ^2,6 ] decanedimethanol represented by the following formula [1-b] and the following formula [1] -C] 3,9-bis (2-hydroxy-1,1-dimethylethyl) -2,4,8,10
-Tetraoxaspiro (5.5) undecane is preferred. These may be used alone or in combination of two or more.

[0030]

[Chemical 16]

Particularly, the aliphatic diol compound constituting the structural unit [A] is preferably cyclohexanedimethanol represented by the above formula [1-a], and may be a cis isomer, a trans isomer or a mixture of cis / trans isomers. Specific examples thereof include 1,2-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, and 1,4-cyclohexanedimethanol. Among them, the following formula [1-
1,4-cyclohexanedimethanol represented by a '] is preferable.

[0032]

[Chemical 17]

The aromatic dihydroxy compound constituting the structural unit [B] represented by the general formula [2] is, 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-tert-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'-dihydroxydiphenyl ether, 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 sulfone, 4,4'-dihydroxy-3,3'-diphenyl sulfide, 4,4'-dihydroxy-3,3'-
Diphenyl sulfoxide, 4,4'-dihydroxy-
3,3′-diphenyl sulfone, α, α′-bis (4-
Hydroxyphenyl) -m-diisopropylbenzene,
Examples include α, α′-bis (4-hydroxyphenyl) -p-diisopropylbenzene and the like.

Among them, 1,1-bis (4-hydroxyphenyl) -1-phenylethane and 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-hydroxy) Phenyl) 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, α, α′-bis (4-hydroxyphenyl) -m-
Diisopropylbenzene and α, α′-bis (4-hydroxyphenyl) -p-diisopropylbenzene are preferred.

Particularly, (i) 2,2-bis (4-hydroxyphenyl) propane represented by the following formula [2-a] [commonly called bisphenol A], (ii) 1 represented by the following formula [2-b] , 1-bis (4-hydroxyphenyl) cyclohexane and (ii) α represented by the following formula [2-c],
α'-Bis (4-hydroxyphenyl) -m-diisopropylbenzene is preferable, and bisphenol A is particularly preferable. These may be used alone or in combination of two or more.

[0036]

[Chemical 18]

Further, as the bisphenols having a cyclic terpene skeleton constituting the structural unit [C-1] represented by the general formula [3], compounds of the following formula [3-1] are exemplified.

[0038]

[Chemical 19]

(However, in the formula [3-1], R ₁₃ , R ₁₄ and R
The definitions of ₁₅ , R ₁₆ , a and b are the same as the definition of the structural unit [3]. Among them, R ₁₃ and R ₁₄ are each preferably an alkyl group having 1 to 3 carbon atoms, more preferably a methyl group, R ₁₅ is preferably an alkyl group having 1 to 4 carbon atoms, more preferably an isopropyl group, R ₁₆ Is preferably an alkyl group having 1 to 3 carbon atoms, more preferably a methyl group, and a and b are each preferably 0 or 1, and more preferably 0. In particular, 1,3-bis (4-hydroxyphenyl) -p-menthane represented by the following formula [III] is preferable. Also,
You may use these individually or in combination of 2 or more types.

[0040]

[Chemical 20]

Further, as the bisphenols having a cyclic terpene skeleton constituting the structural unit [C-2] represented by the general formula [4], compounds of the following formula [4-1] are exemplified.

[0042]

[Chemical 21]

(However, in the formula [4-1], R ₁₇ , R ₁₈ , R
The definitions of ₁₉ , R ₂₀ , R ₂₁ , c and d are the same as the definition of the structural unit [4]. Among them, R ₁₇ and R ₁₈ are each preferably an alkyl group having 1 to 3 carbon atoms, more preferably a methyl group, R ₁₉ is preferably an alkyl group having 1 to 4 carbon atoms, more preferably a methyl group, R ₂₀ And R ₂₁ are each preferably a hydrogen atom, an alkyl group having 1 to 3 carbon atoms or a cycloalkyl group having 6 to 10 carbon atoms, more preferably a methyl group, and c and d are preferably 0 or 1, respectively. It is preferably 0. In particular, 2,8-bis (4-hydroxyphenyl) -p-menthane represented by the following formula [IV] is preferable. These may be used alone or in combination of two or more.

[0044]

[Chemical formula 22]

In the polycarbonate resin copolymer of the present invention, the ratio of (structural unit [A] + structural unit [B]): structural unit [C] is 9 with all the constituent units being 100 mol%.
9: 1 to 70:30 (mol%), preferably 9
It is 8: 2 to 73:27 (mol%), more preferably 96: 4 to 77:23 (mol%), and most preferably 95: 5 to 80:20 (mol%). If the ratio of (structural unit [A] + structural unit [B]) exceeds 99 mol%, the heat resistance will be insufficient, and if it is less than 70 mol%, the balance between the refractive index and the Abbe number will deteriorate, which is not preferable.

The molar ratio of the structural unit [A] to the structural unit [B] is 85:15 to 15:85, preferably 80:20 to 20:80, and more preferably 7.
0:30 to 20:80, most preferably 70: 3
It is 0 to 30:70. If the proportion of the structural unit [A] exceeds 85 mol%, the Abbe number may decrease, and 1
If it is less than 5 mol%, the heat resistance may be deteriorated, which is not particularly preferable as a lens material.

Further, in the structural unit [C], the ratio of the structural unit [C-1] to the structural unit [C-2] is 1 in molar ratio.
00:00 to 50:50, preferably 100: 0
55:45, more preferably 100: 0 to 60:
40, and most preferably 100: 0 to 65:35. If the proportion of the structural unit [C-2] exceeds 50 mol%, the heat resistance may decrease, which is not particularly preferable as a lens material.

The polycarbonate resin copolymer of the present invention comprises a dihydroxy compound (A) represented by the above formula [1-
a] to [1-c] represented by aliphatic diol, (B)
Aromatic bisphenol represented by the formulas [2-a] to [2-c] and (C) bisphenol having a terpene skeleton represented by the formula [3-1] and the formula [4-1] is used. It is manufactured by

As the polymerization method, a method of reacting the dihydroxy compound with phosgene in the presence of an acid binder (solution polymerization method) and a method of transesterifying the dihydroxy compound with a carbonate ester (ester exchange method) are preferably adopted. To be done.

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 mentioned 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, Halogenated hydrocarbons such as dichlorobenzene are preferred, with methylene chloride being most preferred.

The amount of the acid binder used is usually 2 to 100 molar equivalents relative to phosgene, and preferably 2 to
50 molar equivalents are used. Reaction temperature is usually 0 to 100 ° C
And preferably at 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 copolycarbonate resin will be end-capped with groups based on monofunctional phenols. Specific examples of such monofunctional phenols include:
For example, phenol, p-tert-butylphenol,
Included are p-cumylphenol and isooctylphenol. In addition, as other monofunctional phenols,
Phenols or benzoic acid chlorides having a long-chain alkyl group or aliphatic polyester group as a substituent, or 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 with respect to all the terminals of the obtained polycarbonate resin copolymer. Alone or 2
You may use it in mixture of 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 reaction system was set at 1,330 to 13.3 Pa.
The pressure is reduced to a certain degree 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, and particularly preferably 1.0 to 1.1 mol, per mol of the dihydroxy compound. .

In the transesterification method, a polymerization catalyst can be used to accelerate the polymerization rate. Examples of the polymerization catalyst include alkali hydroxides 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.

If necessary, a molecular weight modifier, an antioxidant, etc. may be added. A catalyst deactivator can be added to the obtained polycarbonate resin copolymer. 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. As sulfonic acid ester, methyl benzene sulfonate, ethyl benzene sulfonate, butyl benzene sulfonate, octyl benzene sulfonate,
Phenyl benzenesulfonate, methyl paratoluenesulfonate, ethyl paratoluenesulfonate, butyl paratoluenesulfonate, 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 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, and more preferably in a proportion of 0.8 to 5 mol.

The polycarbonate resin copolymer of the present invention is molded by various molding methods such as injection molding, compression molding, extrusion molding, injection compression molding and solvent casting, and is used for various purposes. Specific applications include lenses, optical disk substrates, light diffusion plates, light guide plates, optical cards, optical prisms, optical molded products such as optical fibers, automobile window glasses and roofs, retardation plates, polarizing plates, wall materials. , Flooring materials, arcade roofing materials, veranda wainscots, windbreaks, snowboards, cases and show windows for exhibition, various trays, various nameplates (protective covers for instruments), seats such as helmet shields, front films for TVs, etc. , Display screens such as retardation films, polarizing films, and plastic films, and film applications such as insulating films.

In particular, the polycarbonate resin copolymer of the present invention has an excellent balance between Abbe number and refractive index and excellent heat resistance, and is therefore suitable as a molding material for lenses.

As the lens, various lenses such as a spectacle lens, a camera lens, a binocular lens, a microscope lens, a projector lens, a Fresnel lens, a lenticular lens, an fθ lens, a headlamp lens or a pickup lens can be used. Among them, the spectacle lens is most suitable because it has a good balance between the refractive index and the Abbe number.

A method known per se can be used for molding a plastic lens using the above polycarbonate resin copolymer. Specifically, the plastic lens of the present invention includes injection molding, compression molding, extrusion molding,
It can be molded by various molding methods such as injection compression molding, and injection compression molding is the most preferable method because it can mold a lens with little optical distortion. In injection compression molding, the cylinder temperature is preferably 200 to 340 ° C, and the mold temperature is preferably 60 to 140 ° C.

The plastic lens 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.

The polycarbonate resin copolymer suitable for the plastic lens 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 0.25 to 0.6 is suitable, and the range of 0.3 to 0.55 is more preferable. Polycarbonate resin copolymer having a specific viscosity in this range,
It has excellent fluidity, can be easily molded by melt injection molding, and the obtained lens has very little optical distortion.

The polycarbonate resin copolymer of the present invention has a relatively high level of refractive index and Abbe number, and has a good balance of these values. Therefore, it is suitable for a spectacle lens. That is, the polycarbonate resin copolymer of the present invention preferably has a refractive index of 1.500.
˜1.600, and more preferably 1.510 to 1.590. The Abbe number is preferably 31 to 48, more preferably 32 to 45.

The polycarbonate resin copolymer of the present invention has a glass transition temperature (Tg) of 100.degree.
A range of 160 ° C is preferable, a range of 105 ° C to 155 ° C is more preferable, and a range of 110 ° C to 150 ° C is further preferable. Polycarbonate resin copolymer has Tg of 160
When the temperature is higher than 0 ° C, the fluidity decreases, and in particular, it becomes difficult to mold the lens by melt injection molding, and the obtained lens has a large optical distortion, which may not be practically usable.

The polycarbonate resin copolymer of the present invention has a photoelastic constant of preferably 75 × 10 ^-8 cm ² / N or less, more preferably 70 × 10 ^-8 cm ² / N or less.

The polycarbonate resin copolymer of the present invention may further contain a phosphorus-containing heat stabilizer in order to prevent a decrease in molecular weight and a deterioration in 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-iso-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-ter
t-butylphenyl) -3,3'-biphenylenediphosphonite, tetrakis (2,6-di-iso-propylphenyl) -4,4'-biphenylenediphosphonite,
Tetrakis (2,6-di-n-butylphenyl) -4,
4'-biphenylene diphosphonite, tetrakis (2,
6-di-tert-butylphenyl) -4,4'-biphenylenediphosphonite, tetrakis (2,6-di-t)
ert-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 and 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 preferably 0.001 to 0.15 parts by weight with respect to 100 parts by weight of the polycarbonate resin copolymer.

Further, in the polycarbonate resin copolymer 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 preferably 0.001 to 0.5 part by weight based on 100 parts by weight of the polycarbonate resin copolymer.

For the purpose of improving weather resistance and cutting off harmful ultraviolet rays, an ultraviolet absorber can be further added to the polycarbonate resin copolymer of the present invention. As such an ultraviolet absorber, 2,2'-dihydroxy-4-
Benzophenone-based UV absorber represented by methoxybenzophenone, 2- (4,6-diphenyl-1,3,5
-Triazin-2-yl) -5-hexyloxyphenol, a triazine-based UV absorber represented by 2- (2
H-benzotriazol-2-yl) -4-methylphenol, 2- (2H-benzotriazol-2-yl)
-4-Tert-octylphenol, 2- (2H-benzotriazol-2-yl) -4,6-bis (1-methyl-1-phenylethyl) phenol, 2- (2H-
Benzotriazol-2-yl) -4,6-di-ter
t-Pentylphenol, 2- (5-chloro-2H-benzotriazol-2-yl) -4-methyl-6-te
rt-Butylphenol, 2- (5-chloro-2H-benzotriazol-2-yl) -2,4-tert-butylphenol and 2,2′-methylenebis [6-
(2H-benzotriazol-2-yl) -4- (1,
1,3,3-tetramethylbutyl) phenol] and the like, and examples thereof include benzotriazole-based ultraviolet absorbers, and these may be used alone or in combination of two or more. These ultraviolet absorbers are generally added in an amount of 0.01 to 1 part by weight, preferably 0.05 to 0.8 part by weight, per 100 parts by weight of the polycarbonate resin copolymer.

When molded into a lens or the like, the polycarbonate resin copolymer of the present invention may contain a bluing agent for canceling the yellow tint of the lens 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
eventViolet36 [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 blended in the polycarbonate resin copolymer in a ratio of 0.3 × 10 ⁻⁴ to 2 × 10 ⁻⁴ parts by weight per 100 parts by weight of the polycarbonate resin copolymer.

To the polycarbonate resin copolymer of the present invention, a generally known antioxidant can be added for the purpose of preventing oxidation. An example thereof is a phenolic antioxidant, 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-tert-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-tert-butyl-4-hydroxybenzyl) benzene, N, N-hexamethylenebis (3,5-di-tert-butyl-4-hydroxyhydrocinnamide), 3,5-di -Tert-butyl-4
-Hydroxybenzylphosphonate diethyl ester,
Tris (3,5-di-tert-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. The preferred range of addition of these antioxidants is 0.0001 to 0.05 parts by weight with respect to 100 parts by weight of the polycarbonate resin copolymer.

[0083]

EXAMPLES The present invention will be further described below with reference to examples. In the examples, parts and% are parts by weight and% by weight. In addition, specific viscosity, refractive index, Abbe number, glass transition temperature,
The photoelastic constant and impact resistance were measured 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 polycarbonate resin casting film (thickness: 100 μm) was prepared and measured at 25 ° C. with an Abbe refractometer manufactured by Atago Co., using diiodomethane as a contact liquid.

(3) Glass transition temperature (Tg) The glass transition temperature (Tg) was measured by a 2910 type DSC manufactured by TA Instruments Japan Co., Ltd. at a heating rate of 10 ° C./min.

(4) Photoelastic constant A photoelastic measuring device PA-150 manufactured by Riken Kikai Co., Ltd. was used to measure a cast film having a thickness of 100 μm.

(5) Falling ball impact test The test was conducted based on the FDA standard using a concave lens of 7.7 mmΦ × 1.5 mm. Specifically, a 15.8 g steel ball was naturally dropped from a height of 127 cm toward the center of the lens for determination. Judgment criteria are: ○: no cracks occurred, ×:
It was determined that cracking occurred.

[Example 1] 64.8 parts by weight (0.45mo) of 1,4-cyclohexanedimethanol (compound of formula [1-a ']; sometimes referred to as CHDM hereinafter)
l), bisphenol A (compound of formula [2-a]; hereinafter sometimes referred to as BPA) 102.6 parts by weight (0.45 mol), 1,3-bis (4-hydroxyphenyl) -p-menthane (Compound of formula [III];
1,3BPMT) 32.4 parts by weight (0.1 mol), diphenyl carbonate 220 parts by weight and tetramethylammonium hydroxide 0.1%.
18 parts by weight and 8 × 10 ⁻⁴ parts by weight of sodium hydroxide were charged into a reaction tank equipped with a stirrer, a distiller and a pressure reducing device, and after nitrogen substitution, they were dissolved at 140 ° C. After stirring for 30 minutes, the internal temperature was raised to 180 ° C and the pressure was gradually reduced to 13.3 kPa.
Was reacted for 30 minutes, and the produced phenol was distilled off.
Next, the temperature was continuously raised while maintaining the same pressure, and phenol was distilled off for reaction for 30 minutes at 190 ° C., 40 minutes at 200 ° C., 30 minutes at 220 ° C., and further 30 minutes at 240 ° C. After that, the pressure was slowly reduced to 260 ° 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, the mixture was stirred at 260 ° C. and 13.3 kPa for 20 minutes, and then discharged from the bottom of the reaction tank under nitrogen pressure, The pellets were cut with a pelletizer while cooling in a water tank. Cylinder temperature 240-260 using the obtained pellets
C. and a mold temperature of 80.degree. C., using a concave lens mold for eyeglasses, a lens was obtained by injection compression molding. This lens had excellent transparency and a good appearance. Table 1 shows various evaluation results
It was shown to.

Example 2 In Example 1, tricyclo [5.2.1.0 ^2,6 ] decanedimethanol (formula [1
-B] compound; hereinafter, may be referred to as TCDDM) 88.2 parts by weight (0.45 mol), bisphenol A 102.6 parts by weight (0.45 mol), 1,3BP
Except that 32.4 parts by weight of MT (0.1 mol) was used,
The same operation as in Example 1 was performed to obtain a polycarbonate resin copolymer and a lens. This lens had excellent transparency and a good appearance. The results of various evaluations are shown in Table 1.

[Embodiment 3] In Embodiment 1, 3, 9-
Bis (2-hydroxy-1,1-dimethylethyl)-
2,4,8,10-Tetraoxaspiro (5.5) undecane (compound of formula [1-c]; hereinafter sometimes referred to as SPG) 167.2 parts by weight (0.55 mol), bisphenol A79. 8 parts by weight (0.35 mol),
A polycarbonate resin copolymer and a lens were obtained in the same manner as in Example 1, except that 32.4 parts by weight of 1,3BPMT (0.1 mol) was used. This lens had excellent transparency and a good appearance. The results of various evaluations are shown in Table 1.

[Embodiment 4] In the first embodiment, CHDM
72.0 parts by weight (0.5 mol), 1,1-bis (4-
Hydroxyphenyl) cyclohexane (compound of formula [2-b]; hereinafter sometimes referred to as BPZ) 107.2
A polycarbonate resin copolymer and a lens were obtained in the same manner as in Example 1 except that 1 part by weight (0.4 mol) and 32.4 parts by weight of 1,3BPMT (0.1 mol) were used. This lens had excellent transparency and a good appearance. The results of various evaluations are shown in Table 1.

[Embodiment 5] In the first embodiment, CHDM
50.4 parts by weight (0.35 mol), α, α′-bis (4-hydroxyphenyl) -m-diisopropylbenzene (compound of formula [2-c]; hereinafter sometimes referred to as BPM) 121.1 Parts by weight (0.35 mol), 1,
A polycarbonate resin copolymer and a lens were obtained in the same manner as in Example 1 except that 97.2 parts by weight of 3BPMT (0.3 mol) was used. This lens had excellent transparency and a good appearance. The results of various evaluations are shown in Table 1.

[Embodiment 6] In the first embodiment, CHDM
57.6 parts by weight (0.4 mol), BPA 91.2 parts by weight (0.4 mol), 1,3BPMT 45.4 parts by weight (0.14 mol), 2,8-bis (4-hydroxyphenyl) -p-menthane (Compound of formula [IV];
A polycarbonate resin copolymer and a lens were obtained in the same manner as in Example 1, except that 19.4 parts by weight (0.06 mol) of 2,8BPMT was used. This lens had excellent transparency and a good appearance. The results of various evaluations are shown in Table 1.

Comparative Example 1 In Example 1, CHDM
A polycarbonate resin copolymer and a lens were obtained in the same manner as in Example 1, except that 72.0 parts by weight (0.5 mol) and 114.0 parts by weight of BPA (0.5 mol) were used. The results of various evaluations are shown in Table 2.

Comparative Example 2 TCDD in Example 1
M 98.0 parts by weight (0.5 mol), BPA 114.0
The same operation as in Example 1 was carried out except that parts by weight (0.5 mol) were used to obtain a polycarbonate resin copolymer and a lens. The results of various evaluations are shown in Table 2.

[Comparative Example 3] In Example 1, SPG1
A polycarbonate resin copolymer and a lens were obtained in the same manner as in Example 1 except that 82.4 parts by weight (0.6 mol) and 91.2 parts by weight of BPA (0.4 mol) were used. The results of various evaluations are shown in Table 2.

COMPARATIVE EXAMPLE 4 In Example 1, CHDM
79.2 parts by weight (0.55 mol), BPZ120.6
The same operation as in Example 1 was carried out except that a part by weight (0.45 mol) was used to obtain a polycarbonate resin copolymer and a lens. The results of various evaluations are shown in Table 2.

[Comparative Example 5] In Example 1, CHDM
A polycarbonate resin copolymer and a lens were obtained in the same manner as in Example 1 except that 72.0 parts by weight (0.5 mol) and 173.0 parts by weight of BPM (0.5 mol) were used. The results of various evaluations are shown in Table 2.

Comparative Example 6 Using bisphenol A type polycarbonate pellets (Panlite L-1250 manufactured by Teijin Chemicals Ltd.), a cylinder temperature of 280 to 30 was obtained.
Injection compression molding was performed at 0 ° C and a mold temperature of 125 ° C to obtain a lens. The results of various evaluations are shown in Table 2.

[0101]

[Table 1]

[0102]

[Table 2]

[0103]

INDUSTRIAL APPLICABILITY The polycarbonate resin copolymer of the present invention is excellent in transparency, fluidity and impact resistance, maintains a good balance between refractive index and Abbe number, and is excellent in optical properties such as low photoelastic constant. In particular, it has good heat resistance.

Therefore, this polycarbonate resin copolymer provides a lens having a small optical distortion and an excellent refractive index and an Abbe number, particularly a spectacle lens, by a molding method having good productivity such as injection compression molding. is there.

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 4J029 AA09 AB01 AC02 AD01 AD07                       AE04 BA02 BA03 BA05 BA08                       BA09 BB12A BB13A BC09                       BD02 BD03A BD07A BD09A                       BE04 BF13 BF30 BH02 DB07                       DB11 DB13 FA07 HC02 HC04A                       HC05A HC06 JF031 JF041                       JF131 JF141 JF321 JF331                       JF361 JF371 JF381

Claims (10)

[Claims] 1. A structure represented by the following general formula [1]:
Unit (structural unit [A]), [Chemical 1] [In the above formula [1], R₁Is an alkane having 1 to 50 carbon atoms
A xylene group, an alicyclic alkylene group having 1 to 50 carbon atoms, or
The following general formula [Chemical 2] And in the formula, R₂And R₃Each independently has 1 to 1 carbon atoms
50 alkylene groups, R _FourIs alkyl having 1 to 10 carbons
The group A is a cycloalkylene group having 1 to 50 carbon atoms or te.
Represents a traoxospiro group, e and f are each independently
0 or 1, provided that the sum of e and f is 1 or more.
And g is the number of replaceable hydrogen atoms present on A from 0.
Is an integer with values up to. ] (B) A structural unit represented by the following general formula [2] (a structural unit
Position [B]) and [Chemical 3] (In the above formula [2], R_FiveAnd R₆Are each independent
Hydrogen atom, halogen atom, alkyl having 1 to 10 carbon atoms
Group, alkoxy group having 1 to 10 carbon atoms, and 6 to 20 carbon atoms
Cycloalkyl group, cycloalkoxy having 6 to 20 carbon atoms
Group, an aryl group having 6 to 10 carbon atoms, an aryl group having 7 to 20 carbon atoms
Ralalkyl group, aryloxy group having 6 to 10 carbon atoms, carbon
An aralkyloxy group of the formula 7 to 20, wherein m and n are
Each is an integer from 0 to 4, and W is [Chemical 4] And here R₇And R₈Are the same or different and are hydrogen atoms
Or represents a hydrocarbon group having 1 to 10 carbon atoms, R₉as well as
R_TenAre each independently a hydrogen atom or a C1-C3
Alkyl group, p is an integer of 4 to 7, R₁₁And R₁₂Is that
Independently, a hydrogen atom, a halogen atom or 1 to 3 carbon atoms
Is an alkyl group. ) (C) A structural unit represented by the following general formula [3] (a structural unit
Position [C-1]) and a structure represented by the following general formula [4]
At least 1 selected from the units (structural unit [C-2])
Consists of two building blocks [C], [Chemical 5] (In the formula, R₁₃, R₁₄, R₁₇And R₁₈Each independently
Halogen atom, C1-10 alkyl group, C1
-10 alkoxy group, cycloalkyl having 6 to 20 carbon atoms
Group, cycloalkoxy group having 6 to 20 carbon atoms, 6 carbon atoms
-10 aryl group, C7-20 aralkyl group,
Aryloxy group having 6 to 10 carbon atoms or 7 to 2 carbon atoms
An aralkyloxy group of 0, wherein a, b, c and d are
Each is an integer of 0 to 4, and R₁₅, R₁₆And R₁₉Haso
Each independently an alkyl group having 1 to 10 carbon atoms or carbon number
6 to 10 aryl groups, R₂₀And R_{twenty one}Are each
Independently hydrogen atom, alkyl group having 1 to 10 carbon atoms, carbon
A cycloalkyl group having 6 to 20 carbon atoms or an alkyl group having 6 to 10 carbon atoms
It is a reel base. ) Assuming that all structural units are 100 mol%, (structural unit [A] +
Structural unit [B]): Ratio of structural unit [C] is 99: 1 to 1
70:30 (mol%), and the structural unit [A] and the structural unit
The molar ratio of the units [B] is 85:15 to 15:85.
Of the structural unit [C-1] and the structural unit [C-2]
Polycarbonate having a molar ratio of 100: 0 to 50:50
Bonate resin copolymer. 2. The aliphatic diol compound constituting the structural unit [A] is represented by the following formulas [1-a], [1-b] and [1].
The polycarbonate resin copolymer according to claim 1, which is at least one compound selected from the group consisting of compounds represented by formula (c). [Chemical 6] 3. The polycarbonate resin copolymer according to claim 1, wherein the aliphatic diol compound constituting the structural unit [A] is a compound represented by the following formula [1-a ′]. [Chemical 7] 4. The aromatic dihydroxy compound constituting the structural unit [B] is selected from the group consisting of compounds represented by the following formulas [2-a], [2-b] and [2-c]. The polycarbonate resin copolymer according to claim 1, which is at least one compound. [Chemical 8] 5. The polycarbonate resin copolymer according to claim 1, wherein the aromatic dihydroxy compound constituting the structural unit [B] is a compound represented by the above formula [2-a]. 6. The structural unit [C] is the same as the above formula [3] and
In the formula [4], R ₁₅Is an isopropyl group, R₁₆,
R₁₉, R₂₀And R_{twenty one}Is a methyl group.
Polycarbonate resin copolymer. 7. In the structural unit [C], in the formula [3] and the formula [4], a, b, c and d are 0, R ₁₅ is an isopropyl group, and R ₁₆ and R _{19 are present.} The polycarbonate resin copolymer according to claim 1, wherein R ₂₀ , R ₂₀ and R ₂₁ are methyl groups. 8. The polycarbonate resin copolymer has a viscosity of 0.
The polycarbonate resin copolymer according to claim 1, which has a specific viscosity of 25 to 0.60. 9. A plastic lens formed from the polycarbonate resin copolymer according to claim 1. 10. The plastic lens according to claim 9, wherein the plastic lens is a spectacle lens.