JPH11166043A - Polyester copolymer and its use - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a polyester copolymer useful for optical parts, excellent in transparency and heat resistance, and low in birefringence by making the copolymer include specific two kinds of repeating structural units in a specific proportion. SOLUTION: This copolymer is obtained by including repeating structural units of formulas I and II [R1 is H or methyl; R2 and R3 are each a (substituted) normal, branched or cyclic alkyl, (substituted) normal, branched or cyclic alkoxy, nitro or halogen; (k) and (l) are each 0 to 20, and (k+1)≠0; and (m) and (n) are each 0 to 3] in the proportion of a repeating structural unit of formula II of 5 to 95 mol.%, pref., 20 to 80 mol.%. The repeating structural units of formulas I and II are obtained from, respectively, dihydroxy compounds of formulas III and IV and 1,4-cyclohexane dicarboxylic acid (derivative). The coplymer is useful for optical parts e.g. an optical disk substrate, pickup lens and prism.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyester copolymer and an optical component comprising the polyester copolymer. The polyester copolymer of the present invention has good transparency, heat resistance, etc., and has low birefringence, and is suitable for optical components such as optical disk substrates, pickup lenses, plastic substrates for liquid crystal cells, prisms, and the like. Useful.

[0002]

2. Description of the Related Art Inorganic glass is used in a wide range of fields as a transparent material because of its excellent properties such as excellent transparency and small optical anisotropy. However,
There are problems such as being heavy and easy to break, poor productivity, and the like, and in recent years, transparent polymers have been actively developed in place of inorganic glass. As a transparent polymer, for example, polymethyl methacrylate, polycarbonate and the like are excellent in transparency, mechanical properties (for example, impact resistance and the like), and are excellent in workability and moldability. It is used for transparent parts and lenses of automobiles.

[0003] On the other hand, sound, images,
The use of optical disks for recording and reproducing information such as characters has been rapidly expanding in recent years. However, in an optical disk used as an information recording medium, not only is it transparent because a laser beam passes through the disk body, but also optical homogeneity is strongly required to reduce an error in reading information. . For example, when a conventionally known polymer (for example, polycarbonate, polymethyl methacrylate, or the like) is used, thermal stress generated in the process of cooling and flowing the resin at the time of molding the disk substrate,
Birefringence occurs when the laser beam passes through the disk substrate due to residual stress due to molecular orientation, volume change near the glass transition point, and the like. The large optical non-uniformity caused by the birefringence is a fatal defect for an optical component such as an optical disc substrate, for example, an error in reading recorded information occurs. In optical components such as the optical disk substrate, a material having higher optical characteristics, that is, a material having low birefringence and excellent transparency and heat resistance is required.

One of the methods for solving the above-mentioned problems is a low-birefringence polycarbonate using a spiro compound, such as a spirobiindanol alone or a copolymerization type polycarbonate of spirobiindanol and bisphenol A. (JP-A-63-31423)
No. 5). However, although the former polycarbonate has low birefringence, it has poor transparency and mechanical strength and has practical problems.In addition, the latter polycarbonate has transparency and mechanical strength due to an increase in bisphenol A component. Although it is improved, there is a problem that the birefringence increases and the range of use as an optical component is limited, and it has been strongly desired to solve these conflicting problems.

Similarly, polymers such as polycarbonate having a spirobichroman structure have been proposed as materials having low birefringence (Japanese Patent Application Laid-Open No. Hei 3-162413). However, even in this polymer, although the spirobichroman derivative alone polycarbonate has low birefringence, transparency and mechanical strength are poor, and there is a practical problem.In addition, the spirobichroman derivative and bisphenol A Although the transparency and the mechanical strength of the copolymerized polycarbonate are improved by the increase of the bisphenol A component, there is a problem that the birefringence is increased. As described above, it has been desired to solve these conflicting problems.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to overcome the above-mentioned problems and to provide a polyester copolymer having good transparency and heat resistance useful for optical parts and having low birefringence. And an optical component comprising the polyester copolymer.

[0007]

Means for Solving the Problems The present inventors have made intensive studies in order to solve the above problems, and as a result, have reached the present invention. That is, the present invention includes a repeating unit represented by the following general formula (A) and a repeating unit represented by the following general formula (B) (Chemical Formula 2). A polyester copolymer having a unit ratio of 5 to 95 mol%, and a polyester copolymer having the ratio of the structural unit represented by the general formula (A) in both structural units of 20 to 80 mol%. Or a polyester copolymer described above or above comprising a repeating structural unit represented by general formula (A) or (B), or an optic comprising the polyester copolymer described in any of above to It concerns parts.

[0008]

Embedded image (Wherein, R ₁ represents a hydrogen atom or a methyl group, and R ₂ and R ₃ each independently represent a linear, branched or cyclic alkyl group which may have a substituent, or a substituent. Represents a linear, branched or cyclic alkoxy group, nitro group or halogen atom, and k and l each independently represent an integer of 0 to 20, provided that k + 1 is not 0, and m and n Each independently represents an integer of 0 to 3)

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. The polyester copolymer of the present invention has the general formula (A)
And a repeating unit represented by the general formula (A) and the general formula (B). In the union, they are present at random, as a monomer or as a block.

In the general formula (A), R ₁ represents a hydrogen atom or a methyl group, and the general formulas (A) and (B)
In the formula, R ₂ and R ₃ are each independently a linear, branched or cyclic alkyl group which may have a substituent,
It represents a linear, branched or cyclic alkoxy group, nitro group or halogen atom which may have a substituent. R ₂
Examples of the substituent of the alkyl group or the alkoxy group represented by R ₃ and R ₃ include an alkyl group, an alkoxy group, an alkoxyalkoxy group, a cycloalkyl group, a heteroatom-containing cycloalkyl group, a cycloalkoxy group, and a heteroatom-containing cycloalkoxy group. , An aryloxy group, an aryloxyalkoxy group, a halogen atom and the like.

Specific examples of R ₂ and R ₃ include methyl, ethyl, n-propyl, isopropyl, n-
Butyl group, isobutyl group, sec-butyl group, tert
-Butyl group, n-pentyl group, n-hexyl group, 2-ethylhexyl group, n-octyl group, n-decyl group, n-
Dodecyl group, n-tetradecyl group, n-octadecyl group, cyclopentyl group, cyclohexyl group, 4-ter
t-butylcyclohexyl group, cycloheptyl group, cyclooctyl group, cyclohexylmethyl group, cyclohexylethyl group, tetrahydrofurfuryl group, methoxyethyl group, ethoxyethyl group, 2-n-butoxyethyl group,
3-methoxypropyl group, 3-ethoxypropyl group, 3
-N-propoxypropyl group, 3-n-butoxypropyl group, 3-n-hexyloxypropyl group, methoxyethoxyethyl group, ethoxyethoxyethyl group, phenoxymethyl group, phenoxyethoxyethyl group, chloromethyl group, chloroethyl group, 3-chloropropyl group, 2,
2,2-trichloroethyl group,

Methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, sec-butoxy, n-pentyloxy, n-
Hexyloxy group, 2-ethylhexyloxyl group, n
-Octyloxy group, n-decyloxy group, n-dodecyloxy group, n-tetradecyloxy group, n-octadecyloxy group, cyclopentyloxy group, cyclohexyloxy group, 4-tert-butylcyclohexyloxy group, cycloheptyloxy group , Cyclooctyloxy group, cyclohexylmethoxy group, cyclohexylethoxy group, methoxyethoxy group, ethoxyethoxy group, n-
Butoxyethoxy group, 3-methoxypropoxy group, 3-
Ethoxypropoxy group, 3-n-propoxypropoxy group, 3-n-butoxypropoxy group, 3-n-hexyloxypropoxy group, methoxyethoxyethoxy group, phenoxymethoxy group, phenoxyethoxyethoxy group,
Examples thereof include a chloromethoxy group, a chloroethoxy group, a 3-chloropropoxy group, a 2,2,2-trichloroethoxy group, a nitro group, a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

R ₂ and R ₃ in the general formulas (A) and (B) are preferably a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms which may have a substituent. An optionally substituted alkoxy group having 1 to 20 carbon atoms, a nitro group or a halogen atom, more preferably an unsubstituted linear or branched alkyl group having 1 to 10 carbon atoms, 10 unsubstituted linear or branched alkoxy group or chlorine atom, more preferably,
Methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, methoxy group, ethoxy group, n-propoxy group, isopropoxy group, n-butoxy group, isobutoxy group, te
It is an rt-butoxy group or a chlorine atom. Particularly preferably, R ₂ and R ₃ are a methyl group or a chlorine atom.

In the general formula (A), k and l
Each independently represents an integer of 0 to 20, preferably an integer of 0 to 10, more preferably 0 to 6
And more preferably an integer of 1 to 4, particularly preferably an integer of 1 to 3. However, k + 1 is 0
Never be. In the general formulas (A) and (B), m and n are each independently an integer of 0 to 3, preferably 0, 1 or 2, and more preferably 0. The repeating structural units represented by the general formulas (A) and (B) contained in the polyester copolymer of the present invention are a dihydroxy compound represented by the general formulas (1) and (3), respectively. Formula (2)
And a 1,4-cyclohexanedicarboxylic acid or a derivative thereof.

[0015]

Embedded image (In the above formula, R ₁ , R ₂ , R ₃ , k, l, m and n represent the same meaning as described above.) As the dihydroxy compound represented by the general formula (1),
Typically, dihydroxy compounds shown in the following Table 1 (Tables 1 to 8) can be exemplified, but of course, the present invention is not limited to these. The dihydroxy compound represented by the general formula (1) may be used alone, or two or more different dihydroxy compounds may be used in combination.

[0016]

[Table 1]

[0017]

[Table 2]

[0018]

[Table 3]

[0019]

[Table 4]

[0020]

[Table 5]

[0021]

[Table 6]

[0022]

[Table 7]

[0023]

[Table 8]

As the dihydroxy compound represented by the general formula (2), representatively, dihydroxy compounds shown in the following Table 2 (Tables 9 to 10) can be exemplified. Of course, the present invention is not limited thereto. It is not limited. The dihydroxy compound represented by the general formula (2) is
They may be used alone or in combination of two or more different types.

[0025]

[Table 9]

[0026]

[Table 10]

The dihydroxy compound represented by the general formula (1) includes a spirobiindanol derivative represented by the following general formula (3) (formula 4), an alkylene oxide such as ethylene oxide and propylene oxide, and ethylene carbonate. , Cyclic carbonates such as propylene carbonate, 2-bromoethanol, 2-chloroethanol,
It can be produced by reaction with β-halohydrins such as 2-bromo-1-propanol. For example, the reaction of a spirobiindanol derivative with an alkylene oxide is described in U.S. Pat. No. 3,794,617, and JP-A-60-55.
No. 78, Japanese Patent Application Laid-Open No. 6-10151, and the like. Also,
For example, the spirobiindanol derivative represented by the general formula (3) and ethylene carbonate or propylene carbonate in xylene can be produced by a heat treatment in the presence of potassium carbonate.

[0028]

Embedded image (Wherein, R ₂ and m represent the same meaning as described above)

The spirobiindanol derivatives represented by the general formulas (2) and (3) can be prepared by a known method, for example, a method described in JP-A-62-10030, that is, 2,2 -Bis (4-hydroxyphenyl) propane derivative is produced according to a method of heat-treating in the presence of perfluoroalkanesulfonic acid. The dihydroxy compounds represented by the general formulas (1) and (2) can be purified by various known methods (for example, column chromatography, distillation, recrystallization and the like). The dihydroxy compound represented by the general formula (1) may be a mixture of dihydroxy compounds having different k and l in the general formula (1) depending on reaction conditions. When the mixture is used as a raw material for parts, it can be suitably used as it is without separation.

The 1,4-cyclohexanedicarboxylic acid and its derivatives used in the production of the polyester copolymer of the present invention are known compounds. As the derivative,
Dicarboxylic acids such as dimethyl 1,4-cyclohexanedicarboxylate, diethyl 1,4-cyclohexanedicarboxylate, di-n-propyl 1,4-cyclohexanedicarboxylate, diisopropyl 1,4-cyclohexanedicarboxylate, and dibutyl 1,4-cyclohexanedicarboxylate Examples thereof include acid ester derivatives, dicarboxylic acid halides such as 1,4-cyclohexanedicarboxylic acid dichloride, 1,4-cyclohexanedicarboxylic acid dibromide, and 1,4-cyclohexanedicarboxylic acid diiodide. In addition, 1,4-cyclohexanedicarboxylic acid and its derivative have a cis form and a trans form, respectively. As a raw material for producing the polyester copolymer of the present invention, only the cis form, only the trans form, or a mixture thereof can be used.

In the structural units represented by the general formulas (A) and (B), the substituent having a hydroxy group forming an ester bond is substituted at the 4-, 5-, 6- or 7-position. The substitution position of the other substituent is at the 4 ′ position,
It is the 5 ', 6' or 7 'position. Among these, preferred substitution positions of the substituent are those represented by general formulas (4-a) to (4).
-E) (Chemical Formula 5), and more preferably a compound of the general formula (4-
a) to general formula (4-d), and particularly preferably general formula (4-a).

[0032]

Embedded image (In the above formula, R represents the above R ₂ or R ₃ , and j is 0 to 3
Represents an integer of

The polyester copolymer of the present invention is a polyester copolymer characterized by containing a repeating structural unit represented by the general formula (A) or (B). And the proportion of the repeating structural unit represented by the general formula (B) is such that the structural unit represented by the general formula (A) is 5 to 95 mol% in both repeating structural units, They can be arbitrarily selected within a range that does not impair the desired effects of various physical properties. A more preferable ratio of the structural unit represented by the general formula (A) is from 20 to 80.
Mol%.

The polyester copolymer of the present invention can be produced by itself according to various known polyester polymerization methods. For example, random or block polyester copolymers composed of repeating structural units represented by the general formulas (A) and (B) are described in, for example, Experimental Chemistry Course, 4th Edition (Vol. 28), Polymer Synthesis, 21
7-231, Maruzen Publishing (1988) [for example, a transpolymerization method, a direct polymerization method, a melt polymerization method such as an acid chloride method, a solution polymerization method, an interfacial polymerization method, etc.] .

In the transesterification method, the above-mentioned dihydroxy compound and the above-mentioned dicarboxylic acid ester derivative are dealcoholized in a molten state or in a solution state under heating and, if desired, reacted in the presence of a catalyst. The direct polymerization method is a method in which the dihydroxy compound and 1,4-cyclohexanedicarboxylic acid are dehydrated and condensed under heating in a molten state or a solution state, and reacted in the presence of a catalyst if desired. The acid chloride method is a method in which the dihydroxy compound and 1,4-cyclohexanedicarboxylic acid chloride are subjected to dehydrochlorination under heating in a molten state, a solution state, or an interfacial polymerization method, and then reacted in the presence of a catalyst if desired. Incidentally, the polymer or oligomer comprising a repeating structural unit represented by the general formula (B) is obtained by converting a dihydroxy compound represented by the general formula (2) and 1,4-cyclohexanedicarboxylic acid dichloride into an organic solvent, a catalyst, water,
It can also be produced by a reaction method using an alkali metal or alkaline earth metal base, that is, an interfacial polymerization method.

The polyester copolymer of the present invention may be a random copolymer or a block copolymer as long as the desired effect is not impaired. For example, when a polyester copolymer comprising repeating structural units represented by the general formulas (A) and (B) is produced as a random copolymer, the general formulas (1) and (2) Can be produced by mixing a dihydroxy compound represented by the following formula and allowing 1,4-cyclohexanedicarboxylic acid or a derivative thereof to act on the mixture. In the case of producing a block copolymer, one of the dihydroxy compounds represented by the general formula (1) or (2) is used alone, and 1,4-cyclohexanedicarboxylic acid or a derivative thereof is used. Act,
It can be produced by preparing a polyester oligomer or polymer and then reacting the other dihydroxy compound or a polyester oligomer or polymer derived from the dihydroxy compound.

The polyester copolymer of the present invention is a polyester copolymer characterized by containing the repeating structural units represented by the general formulas (A) and (B). It may be a polyester copolymer containing (A) and a plurality of different structural units represented by the general formula (B), and other than the structural units represented by the general formulas (A) and (B). Alternatively, a polyester copolymer containing another structural unit may be used. When a structural unit other than the structural units represented by the general formulas (A) and (B) is contained, the structural units represented by the general formulas (A) and (B) occupy all the structural units. The percentage is
There is no particular limitation as long as the desired effects of the present invention are not impaired, but it is 30 mol% or more, preferably 50 mol% or more, and more preferably 70 mol% or more.

The structural unit containing an ester bond other than the structural units represented by the general formulas (A) and (B) includes dihydroxy groups represented by the general formulas (1) and (2). A dihydroxy compound other than the compound,
1,4-cyclohexanedicarboxylic acid or a derivative thereof,
A structural unit obtained from a dicarboxylic acid other than 4-cyclohexanedicarboxylic acid or a derivative thereof, or a dihydroxy compound represented by the general formula (1) or (2), and a dicarboxylic acid other than 1,4-cyclohexanedicarboxylic acid It is a structural unit containing an ester bond obtained from an acid or a derivative thereof.

The general formula (1) used in producing a polyester copolymer having a structural unit containing an ester bond other than the structural units represented by the general formulas (A) and (B) And other dihydroxy compounds other than the dihydroxy compound represented by the general formula (2) include:
Various known aromatic dihydroxy compounds or aliphatic dihydroxy compounds can be exemplified. Specific examples of the aromatic dihydroxy compound include, for example, bis (4-hydroxyphenyl) methane, 1,1-bis (4′-hydroxyphenyl) ethane, 1,2-bis (4′-hydroxyphenyl)
Ethane, bis (4-hydroxyphenyl) phenylmethane, bis (4-hydroxyphenyl) diphenylmethane,
Bis (4-hydroxyphenyl) -1-naphthylmethane, 1,1-
Bis (4'-hydroxyphenyl) -1-phenylethane, 2,
2-bis (4'-hydroxyphenyl) propane ["bisphenol A"], 2- (4'-hydroxyphenyl) -2- (3 '
-Hydroxyphenyl) propane, 2,2-bis (4'-hydroxyphenyl) butane, 1,1-bis (4'-hydroxyphenyl) butane, 2,2-bis (4'-hydroxyphenyl)
-3-Methylbutane, 2,2-bis (4'-hydroxyphenyl)
Pentane, 3,3-bis (4'-hydroxyphenyl) pentane, 2,2-bis (4'-hydroxyphenyl) hexane, 2,2-
Bis (4'-hydroxyphenyl) octane, 2,2-bis (4'-
(Hydroxyphenyl) -4-methylpentane, 2,2-bis (4'-
(Hydroxyphenyl) heptane, 4,4-bis (4'-hydroxyphenyl) heptane, 2,2-bis (4'-hydroxyphenyl) tridecane, 2,2-bis (4'-hydroxyphenyl)
Octane, 2,2-bis (3'-methyl-4'-hydroxyphenyl) propane, 2,2-bis (3'-ethyl-4'-hydroxyphenyl) propane, 2,2-bis (3'-n -Propyl-
4'-hydroxyphenyl) propane, 2,2-bis (3'-isopropyl-4'-hydroxyphenyl) propane, 2,2-
Bis (3'-sec-butyl-4'-hydroxyphenyl)
Propane, 2,2-bis (3'-tert-butyl-4'-hydroxyphenyl) propane, 2,2-bis (3'-cyclohexyl-4'-hydroxyphenyl) propane, 2,2-bis (3 '-Allyl-4'-hydroxyphenyl) propane, 2,
2-bis (3'-methoxy-4'-hydroxyphenyl) propane, 2,2-bis (3 ', 5'-dimethyl-4'-hydroxyphenyl) propane, 2,2-bis (2', 3 ' , 5 ', 6'-Tetramethyl-4'-hydroxyphenyl) propane, bis (4-hydroxyphenyl) cyanomethane, 1-cyano-3,3-bis (4'-hydroxyphenyl) butane, 2,2-bis Bis (hydroxyaryl) alkanes such as (4′-hydroxyphenyl) hexafluoropropane,

1,1-bis (4'-hydroxyphenyl) cyclopentane, 1,1-bis (4'-hydroxyphenyl) cyclohexane, 1,1-bis (4'-hydroxyphenyl) cycloheptane, 1,1 -Bis (3'-methyl-4'-hydroxyphenyl) cyclohexane, 1,1-bis (3 ', 5'-dimethyl-
4'-hydroxyphenyl) cyclohexane, 1,1-bis (3 ', 5'-dichloro-4'-hydroxyphenyl) cyclohexane, 1,1-bis (3'-methyl-4'-hydroxyphenyl) -4- Methylcyclohexane, 1,1-bis (4'-hydroxyphenyl) -3,3,5-trimethylcyclohexane, 2,
2-bis (4'-hydroxyphenyl) norbornane, 2,2-
Bis (hydroxyaryl) cycloalkanes such as bis (4'-hydroxyphenyl) adamantane, 4,4'-dihydroxydiphenyl ether, 4,4'-dihydroxy-3,
Bis (hydroxyaryl) ethers such as 3'-dimethyldiphenylether and ethylene glycol bis (4-hydroxyphenyl) ether, 4,4'-dihydroxydiphenylsulfide, 3,3'-dimethyl-4,4'-dihydroxydiphenylsulfide , 3,3'-Dicyclohexyl-
Bis (hydroxyaryl) sulfides such as 4,4'-dihydroxydiphenyl sulfide and 3,3'-diphenyl-4,4'-dihydroxydiphenyl sulfide;

Bis (hydroxyaryl) sulfoxides such as 4,4'-dihydroxydiphenylsulfoxide and 3,3'-dimethyl-4,4'-dihydroxydiphenylsulfoxide, 4,4'-dihydroxydiphenylsulfone, 4,4 ' -
Bis (hydroxyaryl) sulfones such as dihydroxy-3,3'-dimethyldiphenylsulfone, bis (4-hydroxyphenyl) ketone, bis (4-hydroxy-3-
Bis (hydroxyaryl) ketones such as methylphenyl) ketone, and 7,7′-dihydroxy-3,3 ′,
4,4'-tetrahydro-4,4,4 ', 4'-tetramethyl-2,2'-spirobi (2H-1-benzopyran), trans-2,3-bis (4'-hydroxyphenyl) -2 -Butene, 9,9-bis (4'-hydroxyphenyl) fluorene, 3,3-bis (4 '
-Hydroxyphenyl) -2-butanone, 1,6-bis (4'-
Hydroxyphenyl) -1,6-hexanedione, α, α,
α ', α'-tetramethyl-α, α'-bis (4-hydroxyphenyl) -p-xylene, α, α, α', α'-
Tetramethyl-α, α′-bis (4-hydroxyphenyl) -m-xylene, 4,4′-dihydroxybiphenyl, hydroquinone, resorcin and the like.

As the aliphatic dihydroxy compound, preferably, a dihydroxyalkane having 2 to 20 carbon atoms, a dihydroxycycloalkane having 4 to 12 carbon atoms and a dihydroxy compound represented by the general formula (5) can be exemplified. HO—R ₄ —Y—R ₄ —OH (5) (wherein, R ₄ represents an alkylene group having 1 to 6 carbon atoms, and Y represents a divalent aromatic group having 6 to 20 carbon atoms) Specific examples of the dihydroxy compound include 1,2-
Dihydroxyethane, 1,3-dihydroxypropane,
1,4-dihydroxybutane, 1,5-dihydroxypentane, 3-methyl-1,5-dihydroxypentane,
1,6-dihydroxyhexane, 1,7-dihydroxyheptane, 1,8-dihydroxyoctane, 1,9-dihydroxynonane, 1,10-dihydroxydecane,
1,11-dihydroxyundecane, 1,12-dihydroxydodecan, dihydroxyneopentyl, 2-ethyl-1,2-dihydroxyhexane, 2-methyl-1,
Dihydroxyalkanes such as 3-dihydroxypropane,
Dihydroxycycloalkanes such as 1,3-dihydroxycyclohexane, 1,4-dihydroxycyclohexane and 2,2-bis (4′-hydroxycyclohexyl) propane, and o-dihydroxyxylylene, m-
Dihydroxyxylylene, p-dihydroxyxylylene, 1,4-bis (2'-hydroxyethyl) benzene, 1,4-bis (3'-hydroxypropyl) benzene, 1,4-bis (4'-hydroxybutyl) Examples thereof include dihydroxy compounds such as benzene, 1,4-bis (5′-hydroxypentyl) benzene, and 1,4-bis (6′-hydroxyhexyl) benzene. These dihydroxy compounds may be used alone or in combination of two or more. Among the dihydroxy compounds other than the dihydroxy compounds represented by the general formulas (1) and (2), 9,9′-bis (4′-hydroxyphenyl) fluorene is particularly preferable.

1,4-cyclohexane used for producing a polyester copolymer having a structural unit containing an ester bond other than the structural units represented by the general formulas (A) and (B) As the dicarboxylic acid compound other than the dicarboxylic acid, various known aromatic dicarboxylic acid compounds or aliphatic dicarboxylic acid compounds can be exemplified.

Specific examples include phthalic acid, methylphthalic acid, ethylphthalic acid, methoxyphthalic acid, ethoxyphthalic acid, chlorophthalic acid, bromophthalic acid, isophthalic acid, methylisophthalic acid, ethylisophthalic acid, methoxyisophthalic acid, ethoxyisophthalic acid, Chloroisophthalic acid, bromoisophthalic acid, terephthalic acid, methylterephthalic acid, ethylterephthalic acid, methoxyterephthalic acid, ethoxyterephthalic acid, chloroterephthalic acid, bromoterephthalic acid, 1,4-naphthalenedicarboxylic acid,
1,5-naphthalenedicarboxylic acid, 1,8-naphthalenedicarboxylic acid, 2,3-naphthalenedicarboxylic acid, 2,
6-naphthalenedicarboxylic acid, 2,2'-biphenyldicarboxylic acid, 4,4'-biphenyldicarboxylic acid 4,4'-diphenyletherdicarboxylic acid, 4,4 '
-Diphenyl sulfide dicarboxylic acid, 4,4'-benzophenone dicarboxylic acid, 4,4'-diphenyl sulfone dicarboxylic acid, 4,4'-diphenylmethane dicarboxylic acid, 2,2-bis (carboxyphenyl) propane,
2,2-bis (carboxyphenyl) -1,1,1,
Aromatic dicarboxylic acids such as 3,3,3-hexafluoropropane; malonic acid, succinic acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, decamethylenedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, Aliphatic dicarboxylic acids such as 1,3-cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, norbornane-2,3-dicarboxylic acid and 5-norbornene-2,3-dicarboxylic acid; 1,4-xylylenedicarboxylic acid , 1,3-xylylenedicarboxylic acid, 1,2-xylylenedicarboxylic acid, and the like. These dicarboxylic acids or derivatives thereof may be used alone or in combination of two or more different dicarboxylic acids.

Further, when the present invention is a polyester copolymer containing a copolymer component other than the structural units represented by the general formulas (A) and (B), the general formula (A) and the general formula (B) The structural unit other than the structural unit represented by ()) may be a structural unit containing a bond other than an ester bond. Examples of such a bond include an amide bond, an imide bond, a carbonate bond, and a urethane bond. Such a structural unit is a structural unit derived from a bifunctional compound other than the above dihydroxy compound or dicarboxylic acid derivative, and examples of the bifunctional compound include aromatic diamines, aliphatic diamines, and aromatic chloroforms. Compounds such as mates, aliphatic chloroformates, aromatic diisocyanates, and aliphatic diisocyanates.

In the polyester copolymer of the present invention,
The terminal group may be a reactive terminal group such as a hydroxy group or a carboxyl group, or may be an inactive terminal group sealed with a molecular weight regulator. Here, as the molecular weight regulator, a monovalent hydroxy aliphatic compound or a hydroxy aromatic compound, or a monovalent hydroxy aliphatic compound or an alkali metal or alkaline earth metal salt of a hydroxy aromatic compound, a monovalent hydroxy aliphatic A haloformate compound of an aromatic or hydroxyaromatic compound, a monovalent hydroxyaliphatic compound or a carbonate of a hydroxyaromatic compound, such as a monovalent carboxylic acid,
And alkali metal or alkaline earth metal salts of monovalent carboxylic acids, acid halides of monovalent carboxylic acids, esters of monovalent carboxylic acids, and the like.

Specific examples of the molecular weight regulator include the following compounds. Examples of the monovalent hydroxyaliphatic compound or hydroxyaromatic compound include, for example, methanol, ethanol, butanol, octanol, lauryl alcohol, methoxyethanol, propylene glycol monomethyl ether, cyclohexanol, benzyl alcohol, allyl alcohol, phenol, 4-tert. -Butylphenol, 2-cresol, 3-cresol, 4-cresol, 2-ethylphenol, 4-ethylphenol, 4-cumylphenol, 4-phenylphenol, 4-cyclohexylphenol, 4-n-octylphenol, 4-iso Octylphenol, 4-nonylphenol, 4-methoxyphenol, 4-n-hexyloxyphenol, 4
-Isopropenylphenol, 2-chlorophenol,
3-chlorophenol, 4-chlorophenol, 2-bromophenol, 3-bromophenol, 4-bromophenol, 2,4-dichlorophenol, 2,4-dibromophenol, pentachlorophenol, pentabromophenol, β-naphthol , Α-naphthol, 2-
(4′-methoxyphenyl) -2- (4 ″ -hydroxyphenyl) propane and the like.

Examples of the alkali metal or alkaline earth metal salt of the monovalent hydroxyaromatic compound include the sodium, potassium and calcium salts of the above-mentioned monovalent hydroxyaliphatic compound or hydroxyaromatic compound. Examples of the haloformate derivative of the monovalent hydroxyaliphatic compound or hydroxyaromatic compound include the above-mentioned monovalent hydroxyaliphatic compound or hydroxyaromatic compound, such as chloroformate and bromoformate.

As the monovalent carboxylic acid, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, heptanoic acid, caprylic acid, 2,2-dimethylpropionic acid, 3-methylbutyric acid, 3,3-dimethylbutyric acid, 4-methylvaleric acid, 3,3
Aliphatic carboxylic acids such as dimethylvaleric acid, 4-methylcaproic acid, 2,4-dimethylvaleric acid, 3,5-dimethylcaproic acid, and phenoxyacetic acid; benzoic acid; 4-propoxybenzoic acid; 4-butoxybenzoic acid And benzoic acids such as 4-pentyloxybenzoic acid, 4-hexyloxybenzoic acid, and 4-octyloxybenzoic acid. Examples of the alkali metal or alkaline earth metal salt of a monovalent carboxylic acid include the sodium, potassium, and calcium salts of the above-described monovalent carboxylic acid. Examples of the acid halide derivative of a monovalent carboxylic acid include chlorides and bromides of the above-mentioned monovalent carboxylic acid.

The molecular weight of the polyester copolymer of the present invention is not particularly limited.
The weight average molecular weight as a standard polystyrene equivalent molecular weight measured by (gel permeation chromatography) is 5,000 to 200,000, preferably
10,000 to 150,000, more preferably 1
5000 to 100,000.

The polyester copolymer of the present invention is thermoplastic and can be prepared by injection molding, extrusion molding, blow molding,
Filler or the like can be impregnated, and further, it can be easily molded by various known molding methods such as compression molding and solution casting. In addition, the polyester copolymer of the present invention can also be a blend of a plurality of different polyester copolymers of the present invention, as long as the desired effect is not impaired, other than the polyester copolymer of the present invention.
By blending another known polyester, it can be used as a molding material. In addition, it is possible to use other polymers together as a molding material. Other polymers include polyethylene, polypropylene, polystyrene, ABS resin, polymethyl acrylate, polymethyl methacrylate, polytrifluoroethylene, polytetrafluoroethylene, polyacetal,
Examples thereof include polyphenylene oxide, polycarbonate, polyamide, polyimide, polyamideimide, polyetherimide, polysulfone, polyethersulfone, and polysulfide.

The polyester copolymer of the present invention may be used alone or in combination with other polymers to prepare a pigment, a dye, a heat stabilizer, an antioxidant, or the like by a known method during or after the production of the polyester copolymer. Agents, UV absorbers, release agents, organic halogen compounds, alkali metal sulfonates,
Glass fiber, carbon fiber, glass beads, barium sulfate,
Known additives such as TiO ₂ may be added. The polyester copolymer of the present invention, alone or in a state of being mixed with another polymer, may be added with the above-mentioned additives, if necessary, as a molding material, and may be used as a component of an electric device, an electronic component, an automobile component, an optical disc, or the like. Of the information recording medium, optical materials such as lenses of cameras and spectacles, and building materials instead of glass.

The optical components containing the polyester copolymer of the present invention include optical recording medium substrates such as optical disk substrates and magneto-optical disk substrates, optical lenses such as pickup lenses, plastic substrates for liquid crystal cells, and various optical components such as prisms. Parts can be mentioned. These optical components can be suitably manufactured by various conventionally known molding methods (typically, injection molding and the like) as described above. The optical components obtained in this way are transparent,
It is very useful because it has good heat resistance and low birefringence.

[0054]

EXAMPLES Hereinafter, the present invention will be described in more detail by way of examples, but the present invention is not limited to the following examples. In addition, the molecular weight of the polyester copolymer manufactured in the example and the polycarbonate manufactured in the comparative example was measured by the following method. [Measurement of molecular weight] A 0.2 wt% chloroform solution of a polymer such as a polyester copolymer or a polycarbonate was measured by GPC (gel permeation chromatography) [System-11, manufactured by Showa Denko KK] The weight average molecular weight (Mw) was determined. The measured value is a value in standard polystyrene conversion.

Example 1 [Production of a polyester copolymer using the dihydroxy compound represented by Exemplified Compound 1 and the dihydroxy compound represented by Exemplified Compound 41 in a ratio of 40 mol to 60 mol] A flask having a content of 100 ml , A stirrer, a reflux condenser,
A dip tube for blowing nitrogen was provided. In this flask, 40 ml of monochlorobenzene, 7.93 g (20 mmol) of the dihydroxy compound represented by Exemplified Compound 1 and 9.25 g of the dihydroxy compound represented by Exemplified Compound 41 (3.
0 mmol) was weighed. 9. While blowing in nitrogen and stirring, 1,4-cyclohexanedicarboxylic acid dichloride.
45 g (50 mmol) were added, and the temperature was raised to 130 ° C.
Heated to reflux for an hour. After cooling, the viscous solution containing the product was discharged into methanol, and the precipitated polymer was filtered and washed with methanol. This is dried under reduced pressure, and is a dihydroxy compound derived from the following formula (C) and the compound represented by Exemplified Compound 41. The dihydroxy compound comprises structural units represented by the following formula (D) (Formula 6). D) ratio of 40: 6
A polyester copolymer having a weight average molecular weight of 61,000, which is 0 (molar ratio), was obtained. The structural unit represented by the formula (C) is derived from the dihydroxy compound of Exemplified Compound 1, and the structural unit represented by Formula (D) is derived from the dihydroxy compound of Exemplified Compound 41. is there.

[0056]

Embedded image

Example 2: [Production of a polyester copolymer using the dihydroxy compound represented by Exemplified Compound 1 and the dihydroxy compound represented by Exemplified Compound 41 in a ratio of 50 mol to 50 mol] A flask having a content of 100 ml , A stirrer, a reflux condenser,
A dip tube for blowing nitrogen was provided. While blowing in nitrogen, 19.83 g (50 mmol) of the dihydroxy compound represented by Exemplified Compound 1 and Exemplified Compound 4 in this flask
15.42 g (50 mmol) of the dihydroxy compound represented by 1 and 20.90 g (100 mmol) of 1,4-cyclohexanedicarboxylic acid dichloride were weighed. After the exothermic reaction, the temperature was raised to 50 ° C. and stirred for 10 minutes.
The mixture was heated and stirred at 220 ° C. for 40 minutes while blowing in nitrogen to distill off hydrogen chloride as a by-product. A viscous product in a molten state is taken out of the reactor, and is composed of the structural units represented by the formulas (C) and (D), and the ratio of the formulas (C) and (D) is 50:50 ( (Molar ratio), a polyester copolymer having a weight average molecular weight of 92,000 was obtained.

Examples 3 to 12 In Example 1, instead of using the dihydroxy compound represented by Exemplified Compound 1 and the dihydroxy compound represented by Exemplified Compound 41, the dihydroxy compounds shown in Table 3 (Tables 11 to 13) were used. In the same manner as described in Example 1 except that the above-mentioned was used, various polyester copolymers shown in Table 3 were obtained. However, "dicarboxylic acid" in the table represents 1,4-cyclohexanedicarboxylic acid dichloride.

[0059]

[Table 11]

[0060]

[Table 12]

[0061]

[Table 13]

Comparative Example 1 A known polycarbonate was produced from bisphenol A and phosgene according to the following conventional method (interfacial polymerization method). A 2-liter baffled flask was equipped with a stirrer equipped with a lattice blade, a reflux condenser, and a dip tube for blowing phosgene. The flask was charged with 114 g (0.50 mol) of bisphenol A, 56 g (1.40 mol) of sodium hydroxide, 2.58 g of 4-tert-butylphenol and 600 ml of deionized water. Prepared. Thereafter, 600 ml of dichloromethane was added to the aqueous solution to form a two-phase mixture. While stirring the two-phase mixture, 59.4 g (0.60 mol) of carbonyl chloride was supplied at a rate of 9.9 g / min. After the supply of carbonyl chloride was completed, 0.08 g of triethylamine was added to the reaction mixture, and the mixture was further stirred and mixed for 90 minutes. Thereafter, the stirring was stopped, the reaction mixture was separated, the dichloromethane phase was neutralized with an aqueous hydrochloric acid solution, and washed with deionized water until no electrolyte was substantially detected in the aqueous washing solution. Thereafter, dichloromethane was evaporated from the dichloromethane phase by distillation to obtain a solid aromatic polycarbonate. The weight average molecular weight was 51,000.

Comparative Example 2 A copolymer polycarbonate of bisphenol A and spirobiindanol was produced according to the method described in Example 7 of JP-A-63-314235. The weight average molecular weight was 44,800.

Using the polymers produced in each of the examples and comparative examples, a plate-shaped test piece having a thickness of 1.2 mm was produced by press molding, and the test items described below were subjected to evaluation tests on the test pieces. . The results are shown in Table 4 below (Table 14). [Evaluation Methods] (1) Appearance: The transparency and optical surface state of the test piece were visually observed and evaluated. ：: Colorless and transparent, good surface condition without cracks, cracks, surface roughness, etc. ×: Those with observed cracks, cracks, surface roughness, etc. (2) Total light transmittance (hereinafter, transmittance): ASTM D- 1
003 method was followed. (3) Birefringence: measured by an ellipsometer. (4) Heat resistance: After leaving in a hot-air drying group at 120 ° C. for 4 hours, a test piece was taken out, visually observed and evaluated. ：: No coloring, surface distortion, crack, etc. of the molded product ×: Coloring, surface distortion, crack, etc. of the molded product observed

[0065]

[Table 14] As is clear from Table 4, the molded product obtained by molding the polyester copolymer of the present invention has good transparency, heat resistance, etc., and has low birefringence.

Example 13 (Preparation and evaluation of optical disk) The polyester copolymer produced in Example 1 was formed into pellets using an extruder equipped with a pelletizer (cylinder temperature: 250 ° C). After drying the pellets at 110 ° C. for 4 hours, injection molding was performed at 280 ° C. That is, a stamper having a mirror surface is attached to the mold, and the outer diameter is 130 m.
m, a disk-shaped molded product having a thickness of 1.2 mm was obtained. A central portion of the obtained molded product (substrate) was punched out to have an inner diameter of 15 mm to obtain a donut-shaped disk. Next, aluminum was vacuum-deposited on one side to provide a reflective layer having a thickness of 600 angstroms. Birefringence and BER of the obtained optical disc
(Bit error rate) was measured. Bit error rate: wavelength 780 nm, linear velocity 2 m / sec, 0.8 mW
Was used to measure the rate of occurrence of record reading errors. The results are shown in Table 5 below (Table 15).

Examples 14 to 24 Optical disks were produced and evaluated in the same manner as in Example 13 except that the polyester copolymers produced in Examples 2 to 12 were used. The results are shown in Table 5 below.

Comparative Example 3 An optical disk was produced in the same manner as in Example 13 except that the polymer produced in Comparative Example 1 was used. The results of measuring the birefringence and BER (bit error rate) of the obtained optical disk are shown in Table 5 below.

Comparative Example 4 An optical disk was produced in the same manner as in Example 13 except that the polymer produced in Comparative Example 2 was used. The results of measuring the birefringence and BER (bit error rate) of the obtained optical disk are shown in Table 5 below.

[0070]

[Table 15] As is clear from Table 5, the optical disk of the present invention has an improved BER due to a decrease in birefringence as compared with an optical disk obtained using an existing polymer.

Example 25 (Production of Magneto-Optical Disk and Evaluation of Recording Characteristics) The polyester copolymer obtained in Example 1 was formed into pellets with an extruder equipped with a pelletizer (cylinder temperature 250 ° C.). After drying the pellets at 110 ° C. for 4 hours, injection molding was performed. That is, a stamper having a mirror surface was mounted on a mold to obtain a disk-shaped molded product having an outer diameter of 130 mm and a thickness of 1.2 mm. A sputtering apparatus [R] was formed on the obtained molded product (base) by using an alloy target of Tb23.5, Fe64.2, Co12.3 (atomic%).
F sputtering apparatus, manufactured by Japan Vacuum Co., Ltd.] to form a magneto-optical recording layer having a thickness of 1000 Å.
On this recording film, a protective film of inorganic glass having a thickness of 1000 Å was formed using the same sputtering apparatus as described above. Birefringence of the obtained magneto-optical disk, CN
The ratio, BER (bit error rate) and CN retention were measured. The CN ratio was measured at a writing power of 7 mW, a reading power of 1 mW, a carrier frequency of 1 MHz, and a resolution bandwidth of 30 KHz. CN retention rate is the initial C
The degree of decrease in the CN ratio after 30 days under the conditions of 60 ° C. and 90% RH with respect to the N ratio was indicated by percentage (%). The results are shown in Table 6 below (Table 16).

Examples 26 to 36 Magneto-optical disks were produced in the same manner as in Example 25 except that the copolymerized polyesters produced in Examples 2 to 12 were used. Birefringence of the obtained magneto-optical disk,
The results of measuring the CN ratio, BER (bit error rate) and CN change rate are shown in Table 6 below.

Comparative Example 5 A magneto-optical disk was produced in the same manner as in Example 25 except that the polymer produced in Comparative Example 1 was used. Birefringence, CN ratio, BER of the obtained magneto-optical disk
The results of measuring the (bit error rate) and the CN retention rate are shown in Table 6 below.

Comparative Example 6 A magneto-optical disk was produced in the same manner as in Example 25 except that the polymer produced in Comparative Example 2 was used. Birefringence, CN ratio, BER of the obtained magneto-optical disk
The results of measuring the (bit error rate) and the CN retention rate are shown in Table 6 below.

[0075]

[Table 16] As is clear from Table 6, the magneto-optical disk obtained by using the polyester of the present invention has a lower birefringence, so that the magneto-optical disk obtained from the existing polymer has
The CN ratio and the BER are improved, and the CN retention is improved.

[0076]

According to the present invention, it has become possible to provide a copolymerized polyester having good transparency and heat resistance and low birefringence. The copolymerized polyester of the present invention is very useful as an optical component such as an optical disk substrate and a pickup lens. In particular, a magneto-optical disk substrate obtained using the polyester is excellent in optical recording characteristics and also in durability (heat resistance, moisture resistance, etc.).

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Keisuke Takuma 1190 Kasama-cho, Sakae-ku, Yokohama-shi, Kanagawa Mitsui Chemicals, Inc.

Claims (4)

[Claims] 1. A structural unit represented by the general formula (A) which contains a repeating structural unit represented by the general formula (A) and the general formula (B) (formula 1) and is contained in both structural units. A polyester copolymer having a ratio of 5 to 95 mol%. Embedded image (Wherein, R ₁ represents a hydrogen atom or a methyl group, and R ₂ and R ₃ each independently represent a linear, branched or cyclic alkyl group which may have a substituent, or a substituent. Represents a linear, branched or cyclic alkoxy group, nitro group or halogen atom, and k and l each independently represent an integer of 0 to 20, provided that k + 1 is not 0, and m and n Each independently represents an integer of 0 to 3) 2. The polyester copolymer according to claim 1, wherein the proportion of the structural unit represented by the general formula (A) in both structural units is 20 to 80 mol%. 3. The polyester copolymer according to claim 1, comprising a repeating structural unit represented by the general formula (A) and the general formula (B). 4. An optical component comprising the polyester copolymer according to claim 1.