JP2001195779A - Optical polycarbonate resin molding material and optical disk substrate made therefrom - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical polycarbonate resin molding material capable of keeping high reliability over a long period of time, excellent in heat resistance, satisfactory in release characteristics and capable of enhancing productivity of an optical disk substrate and to provide the optical disk substrate made therefrom. SOLUTION: This optical polycarbonate resin molding material comprises 100 parts by weight of aromatic polycarbonate resin having 10,000-22,000 viscosity average molecular weight (component A), 0.001-0.01 parts by weight of stabilizer (component B) consisting of 10-100 wt.% (based on the total weight of the stabilizer) compound shown by general formula 1 (component B1), 0-80 wt.% compound shown by general formula 2 (component B2) and 0-30 wt.% compound shown by general formula 3 (component B3) and 0.001-0.035 parts by weight of releasing agent (c) shown by general formula 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical polycarbonate resin molding material and an optical disk substrate capable of maintaining high reliability for a long period of time and improving substrate productivity.

[0002]

2. Description of the Related Art Optical disks for recording and reproducing information by irradiating a laser beam include digital audio disks (so-called compact disks), optical video disks (so-called laser disks), various write-once disks, magneto-optical disks, and phase-change disks. Changeable disks and the like have been put to practical use.

[0003] Among them, compact disks and laser disks are read-only (Read Only Memory).
(y: ROM) type optical disk. In these optical disks, pits corresponding to information signals are formed in an uneven shape on a transparent substrate, and an Al reflective layer is formed thereon with a thickness of 40 nm or more. In such an optical disc, an information signal is reproduced by detecting a change in reflectance caused by optical interference generated in the pit.

On the other hand, a write-once optical disc has an R (Recordable) on which arbitrary information can be written by a user.
e) type optical disk, a magneto-optical disk and a phase change type disk are RAMs (Random Access Memory) in which arbitrary information can be repeatedly written.
y) type optical disc.

That is, the R-type optical disk is composed of a write-once recording layer on a transparent substrate, whose optical characteristics are irreversibly changed or irregularities are formed by irradiation with a laser beam. As the recording layer, for example, a cyanine-based, phthalocyanine-based, or azo-based organic dye that is decomposed by heating by laser light irradiation, changes its optical constant, and causes deformation of the substrate due to volume change is used.

A magneto-optical disk allows a user to repeatedly write and erase information.
This is a rewritable optical disk that has a T
A perpendicular magnetization film having a magneto-optical effect (for example, the Kerr effect) such as a b-Fe-Co amorphous alloy thin film is formed. In this magneto-optical disk, recording pits are formed by magnetizing a small region of a perpendicular magnetization film upward or downward in response to an information signal. The information signal is reproduced by utilizing the fact that the rotation angle θk (Kerr rotation angle) of the linearly polarized light in the reflected light differs depending on the direction of magnetization of the perpendicular magnetization film.

A phase-change disk is a rewritable disk like a magneto-optical disk. For example, a Ge-Sb-Te which exhibits a crystalline state in an initial state and changes to an amorphous state when irradiated with a laser beam. A phase change material or the like is used. In this recording layer, recording pits are formed by phase-changing a minute area in response to an information signal.
The information signal is reproduced by detecting a change in the reflectance between the amorphous portion corresponding to the pit and the other crystal region.

In such a magneto-optical disk or a phase change disk, both sides of the recording layer are sandwiched between transparent dielectric layers for the purpose of preventing the recording layer from being oxidized and increasing the signal modulation degree due to multiple interference. In many cases, a four-layer structure in which Al reflective layers are stacked is adopted. In addition, as the dielectric layer, a silicon nitride film, a Zn—SiO ₂ mixed film, or the like is used.

Recently, studies on using such an optical disk for digital video recording have been actively conducted, and a digital versatile disk (DVD) has been developed as such an optical disk.

The DVD has a diameter of 120 mm, which is the same as that of a CD, and records video information corresponding to one movie, so that the DVD can be reproduced with image quality comparable to that of a current television.

Here, recording such video information on an optical disk requires a recording capacity 6 to 8 times that of a CD, for example. For this reason, in DVDs, the laser wavelength is shortened to 635-650 nm compared to 780 nm in CDs, and the numerical aperture (NA) of the objective lens is set to 0.2 in CDs.
By increasing the recording pitch to 0.52 or 0.6 with respect to 45, the track pitch and the minimum recording mark length of the pit are reduced, and the recording density is increased.

[0012] Of these, an increase in the numerical aperture (NA) of the objective lens reduces the allowable amount of warpage of the disk substrate. For this reason, in the case of DVD, the thickness of the substrate is set to CD
By reducing the thickness to 0.6 mm with respect to 1.2 mm, the distance that the laser light passes through the disk substrate is shortened.
The allowance for warpage is compensated (Nikkei Electronics Feb. 27, 1995 No. 63
0). Then, as described in JP-A-6-274940, in order to compensate for a decrease in disk strength due to further thinning of the substrate, the substrate is further laminated on a recording layer formed on the substrate, so-called, Adhered structure is adopted. As the recording layer of the bonded optical disk, any of the ROM-type recording layer, the R-type recording layer, and the RAM-type recording layer used in the above-described single-plate configuration can be adopted.

Further, the bonded optical disk includes a single-sided bonded optical disk using only one surface thereof,
There is a double-sided bonded optical disk using both sides.

For the optical disk substrates as described above, polycarbonate resins excellent in moldability, strength, light transmittance, moisture resistance and the like are often used.

However, the polycarbonate resin having such excellent properties also has a drawback that it is easily hydrolyzed under high temperature and high humidity, and is liable to decrease in molecular weight and impact strength. Further, if the substrate is left under high temperature and high humidity for a long period of time, there is a disadvantage that minute white spots are generated on the substrate and the long-term reliability is impaired.

On the other hand, with the spread of optical disk substrates in recent years, there has been an increasing demand for improved substrate productivity. Resins contain various volatile components, and if molding is performed for a long period of time, various components accumulate on a mold, a stamper, and the like, leading to deterioration of substrate characteristics such as optical and mechanical characteristics.
There is also a problem that the various substrate characteristics are deteriorated.
For this reason, the continuous molding must be temporarily stopped in order to perform maintenance such as cleaning of the mold and the stamper, which has had an adverse effect on the improvement of productivity. Tokuhei 1-2349
No. 8 discloses a composition relating to a polycarbonate resin composition having excellent moldability. However, the composition has not been optimized after considering the productivity improvement taking into account the above deposits and the thermal stability and long-term reliability.
Particularly, in blank media disks such as CD-Rs and MOs whose number of production is larger than that of CDs, and DVDs in which recording is performed at a higher density and higher molding is required, it is strongly desired to optimize the composition.

[0017]

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above problems, and as a result of intensive studies on the problems, the selection of the type of stabilizer and the composition of the stabilizer and the release agent have been made. Optimized for high-quality optics that is made of polycarbonate resin with good heat resistance and sufficient mold releasability, can control substrate degradation very effectively, and maintain high reliability for a long time. I found that a disc was obtained. It has also been found that an optical polycarbonate resin molding material and an optical disk substrate that can improve the productivity of the substrate can be obtained.

[0018]

According to the present invention, there are provided (A) 100 parts by weight of an aromatic polycarbonate resin having a viscosity average molecular weight of 10,000 to 22,000 (component (A)), and (B) a compound represented by the following general formula (1). A compound (component B-1) represented by the following general formula (2) (component B-2) and a compound represented by the following general formula (3) (component B-3). When the total is 100% by weight, the B-1 component is 10 to 1%.
00% by weight, 0 to 80% by weight of B-2 component and B-3
0.001 to 0.1% by weight of a stabilizer
0.01 to 0.01 parts by weight and (C) a release agent (component C) comprising a compound represented by the following general formula (4): 0.001 to 0.03
This is achieved by an optical polycarbonate resin molding material comprising 5 parts by weight and an optical disk substrate therefrom.

[0019]

Embedded image

[In the formula, Ar ₁ is an aromatic group having a dialkyl substituent, which may be the same or different. Ar ₂ and Ar ₃ are aromatic groups which may have an alkyl substituent, and may be the same or different. R ₁
Represents a (t + u) -valent alkyl group having 1 to 22 carbon atoms;
R ₂ represents an alkyl group having 12 to 22 carbon atoms. t represents 0 or a positive integer, u represents a positive integer, and (t +
u) has an integer from 1 to 6. In the present invention, CD-R, CD-RW, MO and digital video disk, DVD-ROM, DVD-a
Good and sufficient releasability as a substrate of an optical disk of a digital versatile disk (DVD) represented by audio, DVD-R, DVD-RAM, etc., particularly a disk substrate used for a high-density optical disk such as a DVD substrate; In order to obtain sufficient reliability and improve the productivity of the substrate, the molding material to be used for molding the substrate is (A) an aromatic polycarbonate resin having a viscosity average molecular weight of 10,000 to 22,000. Parts by weight, (B) component B-1, component B-2
When the total is 100% by weight, the component B-1 is 10 to 100% by weight and the component B-2
0.001 to 0.01 parts by weight of a stabilizer containing 0 to 80% by weight of the component and 0 to 30% by weight of the component B-3, and 0.001 to 0.1% of a releasing agent comprising the component (C). It is necessary to comprise 035 parts by weight.

The stabilizer (B component) of the present invention comprises a B-1 component,
It consists of B-2 component and B-3 component, and the total is 10
0% by weight, the component B-1 is 10 to 100% by weight,
0 to 80% by weight of component B-2 and 0 to 3 of component B-3
0% by weight. Preferably, the B-1 component is 60 to 10
0% by weight, 0 to 40% by weight of the B-2 component and 0 to 20% by weight of the B-3 component, more preferably 70 to 100% by weight of the B-1 component and 0 to 0% by weight of the B-2 component. 30% by weight
And the component B-3 is 0 to 10% by weight. Substantially B
Most preferred are stabilizers consisting of only one component.

In the component B-1 of the present invention, Ar ₁ in the general formula (1) is an aromatic group having a dialkyl substituent, and the three Ar ₁ may be the same or different. The alkyl group has 1 to 12 carbon atoms, preferably 1 carbon atom.
To 6, particularly preferably 1 to 4, and the aromatic group includes a phenyl group, a tolyl group or a diphenyl group, and a phenyl group is preferable.

Specific examples of the component B-1 of the present invention include:
For example, tris (dimethylphenyl) phosphite, tris (diethylphenyl) phosphite, tris (di-i
so-propylphenyl) phosphite, tris (di-
n-butylphenyl) phosphite, tris (2,4-
Di-tert-butylphenyl) phosphite, tris (2,6-di-tert-butylphenyl) phosphite, and the like, preferably tris (dialkyl-substituted phenyl) phosphite, and tris (di-tert-butylphenyl). Phosphite is more preferred, and tris (2,
4-Di-tert-butylphenyl) phosphite is particularly preferred. The compound of the component B-1 is one kind or two kinds.
It may be a mixture of more than one species.

The components B-2 and B-3 of the present invention comprise:
In formulas (2) and (3), Ar ₂ and Ar ₃ are aromatic groups which may have the same or different alkyl substituents.
The aromatic group may not be substituted with an alkyl group,
In the case of being substituted, the number of substitution of the alkyl group is 1 to 3, preferably 1 to 2, and particularly preferably 2 per aromatic group. Alkyl group as a substituent,
It preferably has 1 to 6 carbon atoms, preferably 1 to 4 carbon atoms. Examples of the aromatic group include a phenyl group, a tolyl group and a diphenyl group, and a phenyl group is preferable.

Specific examples of the component B-2 of the present invention include:
For example, 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′-biphenylenediphosphonite, tetrakis (2,4-di-tert)
-Butylphenyl) -4,3'-biphenylenediphosphonite, tetrakis (2,4-di-tert-butylphenyl) -3,3'-biphenylenediphosphonite, tetrakis (2,6-di-iso-propyl) Phenyl)-
4,4′-biphenylenediphosphonite, tetrakis (2,6-di-n-butylphenyl) -4,4′-biphenylenediphosphonite, tetrakis (2,6-di-te
rt-butylphenyl) -4,4′-biphenylenediphosphonite, tetrakis (2,6-di-tert-butylphenyl) -4,3′-biphenylenediphosphonite, tetrakis (2,6-di-tert-) Butylphenyl) -3,3'-biphenylenediphosphonite and the like, and tetrakis (di-tert-butylphenyl)-
Biphenylenediphosphonite is preferred, and tetrakis (2,4-di-tert-butylphenyl) -biphenylenediphosphonite is more preferred. The tetrakis (2,4-di-tert-butylphenyl) -biphenylenediphosphonite is preferably a mixture of two or more,
Specifically, tetrakis (2,4-di-tert-butylphenyl) -4,4′-biphenylenediphosphonite (B-2-1 component), tetrakis (2,4-di-tert-butylphenyl)
t-butylphenyl) -4,3′-biphenylenediphosphonite (B-2-2 component) and tetrakis (2,
More preferred are three mixtures of 4-di-tert-butylphenyl) -3,3'-biphenylenediphosphonite (B-2-3 component). The mixture ratio of this mixture is B
-2-1 component, B-2-2 component, and B-2-3 component are preferably in a weight ratio of 100: 37 to 64: 4 to 14, more preferably 100: 40 to 60: 5 to 11. preferable.

Specific examples of the component B-3 of the present invention include:
Bis (2,4-di-iso-propylphenyl) -4-
Phenyl-phenylphosphonite, bis (2,4-di-
n-butylphenyl) -3-phenyl-phenylphosphonite, bis (2,4-di-tert-butylphenyl) -4-phenyl-phenylphosphonite, bis (2,4-di-tert-butylphenyl)- 3-phenyl-phenylphosphonite bis (2,6-di-iso
-Propylphenyl) -4-phenyl-phenylphosphonite, bis (2,6-di-n-butylphenyl) -3
-Phenyl-phenylphosphonite, bis (2,6-di-tert-butylphenyl) -4-phenyl-phenylphosphonite, bis (2,6-di-tert-butylphenyl) -3-phenyl-phenylphosphonite And bis (di-tert-butylphenyl) -phenyl-phenylphosphonite.
4-Di-tert-butylphenyl) -phenyl-phenylphosphonite is more preferred. This screw (2,4-
Di-tert-butylphenyl) -phenyl-phenylphosphonite is preferably a mixture of two or more, specifically, bis (2,4-di-tert-butylphenyl)-
4-phenyl-phenylphosphonite (B-3-1 component) and bis (2,4-di-tert-butylphenyl) -3-phenyl-phenylphosphonite (B-3
-2 components) are more preferred. The mixing ratio of this mixture is preferably in the range of 5: 1 to 4 by weight, and more preferably in the range of 5: 2 to 3, for the B-3-1 component and the B-3-2 component.

The amount of the stabilizer (component B) of the present invention is 0.00 based on 100 parts by weight of the aromatic polycarbonate resin.
1 to 0.01 parts by weight, and 0.001 to 0.00
The range of 7 parts by weight is more preferable, and 0.001 to 0.005.
The range of parts by weight is most preferred.

The C component as the release agent of the present invention is represented by the general formula (4), wherein R ₁ is an alkyl group having 1 to 22 carbon atoms and a (t + u) valence, and is preferably Carbon number 1
-20 alkyl groups. R ₂ has 12 to ₂ carbon atoms.
2, preferably an alkyl group having 14 to 20 carbon atoms.
Further, t is 0 or a positive integer, and u represents a positive integer of 1 to 4, but the sum of (t + u) is an integer of 1 to 6, and 1 to 4
Is preferably an integer.

The release agent (component C) of the present invention is preferably an ester of a monohydric alcohol and a fatty acid and / or a partial ester or a whole ester of a polyhydric alcohol and a fatty acid. Specific examples of the component C include, for example, stearyl stearate, palmityl palmitate, butyl stearate, methyl laurate, isopropyl palmitate, monoglyceride stearate, diglyceride stearate, triglyceride stearate, monosorbitate stearate, behenin Acid monoglyceride, pentaerythritol monostearate, pentaerythritol tetrastearate, pentaerythritol tetraperargonate, propylene glycol monostearate, biphenyl biphenate, sorbitan monostearate, 2-ethylhexyl stearate, dipentaerythritol hexa Examples include dipentaerythritol full esters or partial esters such as stearate.

Among these esters, monoglyceride stearate, triglyceride stearate, pentaerythritol tetrastearate, triglyceride stearate and stearyl stearate are preferably used. In particular, stearic acid monoglyceride, pentaerythritol tetrastearate, stearic acid triglyceride and stearyl stearate are preferably used, and among them, stearic acid monoglyceride is most preferable. The compound of the component C may be one kind or a mixture of two or more kinds.

The amount of the release agent of the present invention is 0.001 to 0.0 per 100 parts by weight of the aromatic polycarbonate resin composition.
35 parts by weight, preferably 0.01 to 0.025 parts by weight.

The molecular weight of the aromatic polycarbonate resin (A component) used in the present invention is a viscosity average molecular weight (M),
10,000-22,000 is preferred, and 12,000-
20,000 is more preferable, and 13,000 to 18,000
0 is particularly preferred. A polycarbonate resin having such a viscosity average molecular weight is preferable because sufficient strength is obtained as an optical material, and the melt fluidity during molding is good, and molding distortion is not generated.

The viscosity average molecular weight in the present invention is as follows: 100 g of methylene chloride and 0.7 g of an aromatic polycarbonate resin.
Is measured at 20 ° C. using a specific viscosity (η
_SP ) in the following equation.

Η _SP /c=[η]+0.45×[η] ² c
(Where [η] is the intrinsic viscosity) [η] = 1.23 × 10 ⁻⁴ M ^0.83 c = 0.7 The polycarbonate resin used as the component (A) in the present invention is usually a dihydric phenol and a carbonate precursor. Are reacted by an interfacial polymerization method or a melt polymerization method. Representative examples of the dihydric phenol used here include hydroquinone, resorcinol, 4,4 ′
-Dihydroxydiphenyl, bis (4-hydroxyphenyl) methane, bis {(4-hydroxy-3,5-dimethyl) phenyl} methane, 1,1-bis (4-hydroxyphenyl) ethane, 1,1-bis (4 -Hydroxyphenyl) -1-phenylethane, 2,2-bis (4-hydroxyphenyl) propane (commonly known as bisphenol A), 2,2-bis} (4-hydroxy-3-methyl)
Phenyl {propane, 2,2-bis {(4-hydroxy-3,5-dimethyl) phenyl} propane, 2,2-bis {(3,5-dibromo-4-hydroxy) phenyl} propane, 2,2- Bis {(3-isopropyl-4-hydroxy) phenyl} propane, 2,2-bis {(4-hydroxy-3-phenyl) phenyl} propane, 2,2
-Bis (4-hydroxyphenyl) butane, 2,2-bis (4-hydroxyphenyl) -3-methylbutane,
2,2-bis (4-hydroxyphenyl) -3,3-dimethylbutane, 2,4-bis (4-hydroxyphenyl)
-2-methylbutane, 2,2-bis (4-hydroxyphenyl) pentane, 2,2-bis (4-hydroxyphenyl) -4-methylpentane, 1,1-bis (4-hydroxyphenyl) cyclohexane, 1-bis (4-
(Hydroxyphenyl) -4-isopropylcyclohexane, 1,1-bis (4-hydroxyphenyl) -3,3,
5-trimethylcyclohexane, 9,9-bis (4-hydroxyphenyl) fluorene, 9,9-bis {(4-
(Hydroxy-3-methyl) phenyl} fluorene, α,
α'-bis (4-hydroxyphenyl) -o-diisopropylbenzene, α, α'-bis (4-hydroxyphenyl) -m-diisopropylbenzene, α, α'-bis (4-hydroxyphenyl) -p-diisopropyl Benzene, 1,3-bis (4-hydroxyphenyl) -5,7
-Dimethyladamantane, 4,4'-dihydroxydiphenylsulfone, 4,4'-dihydroxydiphenylsulfoxide, 4,4'-dihydroxydiphenylsulfide, 4,4'-dihydroxydiphenylketone,
4'-dihydroxydiphenyl ether and 4,4 '
-Dihydroxydiphenyl ester and the like, and these can be used alone or in combination of two or more.

Among them, bisphenol A, 2,2-bis {(4-hydroxy-3-methyl) phenyl} propane, 2,2-bis (4-hydroxyphenyl) butane,
2,2-bis (4-hydroxyphenyl) -3-methylbutane, 2,2-bis (4-hydroxyphenyl) -3,
3-dimethylbutane, 2,2-bis (4-hydroxyphenyl) -4-methylpentane, 1,1-bis (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane and α, α′-bis ( 4-hydroxyphenyl)
Homopolymers or copolymers obtained from at least one bisphenol selected from the group consisting of -m-diisopropylbenzene are preferred, and bisphenol A is particularly preferred.
And 1,1-bis (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane and bisphenol A, 2,2-bis {(4-hydroxy-3-methyl) phenyl} propane or α, α'-bis (4-
A copolymer with (hydroxyphenyl) -m-diisopropylbenzene is preferably used.

As the carbonate precursor, carbonyl halide, carbonate ester, haloformate and the like are used, and specific examples include phosgene, diphenyl carbonate and dihaloformate of dihydric phenol.

In producing the polycarbonate resin by reacting the dihydric phenol with the carbonate precursor by an interfacial polymerization method or a melt polymerization method, a catalyst, an antioxidant for the dihydric phenol and the like may be used as necessary. You may. Further, the polycarbonate resin may be a branched polycarbonate resin obtained by copolymerizing a trifunctional or higher polyfunctional aromatic compound, or a polyester carbonate resin obtained by copolymerizing an aromatic or aliphatic bifunctional carboxylic acid, Further, a mixture of two or more of the obtained polycarbonate resins may be used.

The reaction by the interfacial polymerization method is usually a reaction between dihydric phenol and phosgene, and is carried out in the presence of an acid binder and an organic solvent. As the acid binder, for example, an alkali metal hydroxide such as sodium hydroxide or potassium hydroxide or an amine compound such as pyridine is used. As the organic solvent, for example, halogenated hydrocarbons such as methylene chloride and chlorobenzene are used. Further, for promoting the reaction, for example, a catalyst such as a tertiary amine such as triethylamine, tetra-n-butylammonium bromide, or tetra-n-butylphosphonium bromide, a quaternary ammonium compound, or a quaternary phosphonium compound may be used. it can. At that time, the reaction temperature is usually 0 to 40 ° C., the reaction time is preferably about 10 minutes to 5 hours, and the pH during the reaction is preferably maintained at 9 or more.

The reaction by the melt polymerization method is usually a transesterification reaction between a dihydric phenol and a carbonate ester, and a simple reaction is carried out by mixing the dihydric phenol with the carbonate ester in the presence of an inert gas while heating. It is carried out by a method of distilling a functional phenol. The reaction temperature varies depending on the boiling point of the monofunctional phenols to be produced and the like, but is usually in the range of 120 to 350 ° C. In the latter stage of the reaction, the pressure of the reaction system is reduced to about 1330 to 13.3 Pa to facilitate the distillation of the monofunctional phenols produced. Since the monofunctional phenols generated during the reaction remain in the polycarbonate resin, a sufficient reaction time is required, and the reaction time is about 1 to 4 hours.

Examples of the carbonate ester include an ester such as an aryl group having 6 to 10 carbon atoms which may have a substituent, an aralkyl group or an alkyl group having 1 to 4 carbon atoms. Specifically, diphenyl carbonate,
Ditolyl carbonate, dinaphthyl carbonate, bis (diphenyl) carbonate, dimethyl carbonate, diethyl carbonate, dibutyl carbonate and the like can be mentioned, among which diphenyl carbonate is preferable.

Further, a polymerization catalyst can be used to increase the polymerization rate. Examples of the polymerization catalyst include sodium hydroxide, potassium hydroxide, alkali metal compounds such as sodium and potassium salts of dihydric phenol, and water. Alkaline earth metal compounds such as calcium oxide, barium hydroxide and magnesium hydroxide; nitrogen-containing basic compounds such as tetramethylammonium hydroxide, tetraethylammonium hydroxide, trimethylamine and triethylamine; alkoxides of alkali metals and alkaline earth metals Manganese, organic acid salts of alkali metals and alkaline earth metals, zinc compounds, boron compounds, aluminum compounds, silicon compounds, germanium compounds, organic tin compounds, lead compounds, osmium compounds, antimony compounds Compounds, titanium compounds, usually the esterification reaction, such as zirconium compounds, there can be used a catalyst used in the transesterification reaction. The catalyst may be used alone or in combination of two or more. The amount of the polymerization catalyst to be used is preferably 1 × 10 ⁻⁸ to 1 × 10 ⁸ per 1 mol of the starting dihydric phenol.
^-4 equivalents, more preferably 1 × 10 ^{−7 to} 5 × 10 ⁻⁴ equivalents.

In such a polymerization reaction, in order to reduce the number of phenolic terminal groups, a terminator such as bis (nitrophenyl) carbonate, bis (phenylphenyl) carbonate, nitrophenyl is used later or after the polycondensation reaction. It is preferred to add compounds such as phenyl carbonate, phenylphenyl carbonate, methoxycarbonylphenylphenyl carbonate and ethoxycarbonylphenylphenyl carbonate. Among them, 2-methoxycarbonylphenylphenyl carbonate is preferably used.

In the polymerization reaction of the polycarbonate resin by the interfacial polymerization method, a terminal stopper is used. The terminating agent is used for controlling the molecular weight, and the obtained polycarbonate resin has excellent thermal stability as compared with the non-terminated one because the terminal is blocked.

As such a terminal terminator, monofunctional phenols represented by the following general formulas (5) to (7) can be shown.

[0045]

Embedded image

[Wherein A is a hydrogen atom or a carbon number of 1 to 9]
Is an alkyl group or a phenylalkyl group (where the carbon number of the alkyl portion is 1 to 9), and r is 1 to 5, preferably 1
-3.].

[0047]

Embedded image

[0048]

Embedded image

Wherein X is -RO-, -R-CO-O
— Or —RO—CO—, wherein R represents a single bond or a divalent aliphatic hydrocarbon group having 1 to 10, preferably 1 to 5 carbon atoms, and n represents an integer of 10 to 50. Show. Specific examples of the monofunctional phenol represented by the general formula (5) include phenol, isopropylphenol, p-tert-butylphenol, p-cresol, p-cumylphenol, and isooctylphenol.

The monofunctional phenols represented by the above general formulas (6) to (7) are phenols having a long-chain alkyl group or aliphatic polyester group as a substituent, When the ends of the resin are blocked, they not only function as a terminator or a molecular weight regulator, but also improve the melt flowability of the resin and facilitate molding processing, as well as physical properties as a substrate, particularly of the resin. It has the effect of lowering the water absorption,
It is also preferably used because it has the effect of reducing the birefringence of the substrate.

As the substituted phenols of the above general formula (6), those having n of 10 to 30, especially 10 to 26 are preferable. Specific examples thereof include decyl phenol, dodecyl phenol, tetradecyl phenol, hexadecyl phenol and Octadecylphenol, eicosylphenol, docosylphenol, triacontylphenol and the like can be mentioned.

As the substituted phenols of the above general formula (7), a compound in which X is -R-CO-O- and R is a single bond is suitable, and n is 10 to 30, especially 10 to 30
26 are preferred, examples of which include, for example, decyl hydroxybenzoate, dodecyl hydroxybenzoate, tetradecyl hydroxybenzoate, hexadecyl hydroxybenzoate, eicosyl hydroxybenzoate, docosyl hydroxybenzoate and tricontyl hydroxybenzoate. No.

Among these monofunctional phenols, monofunctional phenols represented by the above formula (5) are preferred, more preferably alkyl-substituted or phenylalkyl-substituted phenols, and particularly preferably p-tert.
-Butylphenol or p-cumylphenol.

These monofunctional phenolic terminal stoppers are desirably introduced at least 5 mol%, preferably at least 10 mol%, based on all terminals of the obtained polycarbonate resin. The terminal stoppers may be used alone or in combination of two or more.

The raw material polycarbonate resin is produced by a conventionally known ordinary method (interfacial polymerization method, melt polymerization method, etc.), and then subjected to alkali extraction or filtration in a solution state, or granulated raw material after granulation (desolvation). Is washed with poor solvents and non-solvents of polycarbonate resins such as ketones such as acetone, aliphatic hydrocarbons such as hexane, and aromatic hydrocarbons such as xylene to remove impurities and foreign substances such as low molecular weight components and unreacted components. Removal is preferred. Further, in the extrusion step (pelletizing step) of obtaining a pellet-like polycarbonate resin for use in injection molding, it is preferable to remove foreign matters by means such as passing through a sintered metal filter having a filtration accuracy of 10 μm in a molten state. In any case, it is important that the raw material resin before the injection molding has the content of foreign matter, impurities, solvent and the like as low as possible. Also,
In the polycarbonate resin of the present invention, in addition to the above-described stabilizer and release agent, various additives such as an antioxidant, an ultraviolet absorber, and an antistatic agent may be used alone or in combination of two or more. it can.

In the preparation of the aromatic polycarbonate resin molding material of the present invention, in order to blend the aromatic polycarbonate resin with a stabilizer, a release agent and other compounding additives,
Any method is employed. For example, a method of mixing with a tumbler, a V-type blender, a super mixer, a Nauta mixer, a Banbury mixer, a kneading roll, an extruder or the like is appropriately used. The aromatic polycarbonate resin molding material powder and pellet blend product thus obtained are:
Once pelletized as it is or with a melt extruder,
A molded article or sheet can be formed by a generally known method such as an injection molding method, an extrusion molding method, a compression molding method, and a sheet extrusion method.

The blending of the stabilizer, release agent and other additives may be carried out in one stage, or may be carried out in two or more stages. In a method carried out in two stages, for example, after blending a part of the aromatic polycarbonate resin powder or pellets to be blended with the blending additive, that is, diluting the blending additive with the aromatic polycarbonate resin powder There is a method in which a masterbatch of the additives is used to make a final blend using the masterbatch.

For example, in the method of blending in one step, a method in which a predetermined amount of the components B-1 to B-3 and C is preliminarily mixed is blended with an aromatic polycarbonate resin powder or pellets. It is possible to adopt a method in which a fixed amount of each of the components B-1 to B-3 and the component C is separately measured, and the resulting components are sequentially added to the aromatic polycarbonate resin powder or pellets and then blended.

For compounding the stabilizer, the release agent, and other additives, a method of directly adding and pouring the additives into the extruder, or pouring after heating and melting may be employed. In the interfacial polymerization method, a method in which a stabilizer and a release agent are added and dissolved in an organic solvent solution of the aromatic polycarbonate resin after the polymerization can be adopted.

When an optical disk substrate is manufactured from the above polycarbonate resin, an injection molding machine (including an injection compression molding machine) is used. As this injection molding machine, a commonly used one may be used, but from the viewpoint of suppressing the generation of carbides and increasing the reliability of the disk substrate, the adhesion to the resin as a cylinder or a screw is low, and the corrosion resistance and abrasion resistance are low. It is preferable to use a material made of a material having properties.
Injection molding conditions are cylinder temperature 300-400.
C. and a mold temperature of 50 to 140 ° C. are preferred, whereby an optically excellent optical disc substrate can be obtained. The environment in the molding step is preferably as clean as possible from the viewpoint of the present invention. It is also important to sufficiently dry the material to be subjected to molding to remove moisture, and to take care not to cause stagnation that may cause decomposition of the molten resin. It is also important to take care not to use a substrate having an abnormality in birefringence, mechanical characteristics, etc. as a product or a test substrate.

The optical disc substrate made of the optical polycarbonate resin molding material according to the present invention has very few white spots even when kept under high temperature and high humidity conditions for a long time.
DR, CD-RW, MO and digital video disk, DVD-ROM, DVD-audio, DVD-
R, a substrate of an optical disk of a digital versatile disk (DVD) represented by a DVD-RAM, etc.
Excellent as a substrate for VD. The characteristics under the conditions of high temperature and high humidity are as follows: the disk has a size of 20 μm after being left in a thermo-hygrostat controlled at a temperature of 80 ° C. and a relative humidity of 85% for 1000 hours.
It is confirmed by examining the number of white spots of μm or more. The number of white spots generated on a disk obtained from the polycarbonate resin molding material according to the present invention is 2 or less per substrate having a diameter of 120 mm, and preferably 1 or less.

[0062]

The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples. The evaluation was performed according to the following method.

(1) Thermal stability test A sample pellet was dried at 120 ° C. for 5 hours, and then retained at a cylinder temperature of 340 ° C. for 10 minutes using an injection molding machine SG-150 manufactured by Sumitomo Heavy Industries, Ltd. Test piece (length 70 mm, width 50 mm, thickness 2 mm)
Were prepared, and the change in hue was measured. The change in hue was calculated from the following formula by measuring L, a, and b values. ΔE = ｛(LL ′) ² + (aa ′) ² + (bb ′)
² ｝ ^1/2 (L, a, b are not retained, L ', a', b 'are retained for 10 minutes)

(2) Long-term reliability test Molding machine for disks [Meiki Seisakusho M-35BD-DM]
Optical disc substrate (diameter 120 mm,
(Thickness: 1.2 mm) was left in a thermo-hygrostat controlled at a temperature of 80 ° C. and a relative humidity of 85% for 1000 hours, and the number of white spots having a size of 20 μm or more in the substrate was counted. This is 25
The measurement was performed on a plurality of optical disc substrates, the average value was obtained, and this was defined as the number of white spots. An arbitrary substrate was selected from the 25 substrates left for 1000 hours, and the viscosity average molecular weight was measured. The value obtained by subtracting the viscosity average molecular weight of the substrate subjected to the long-term reliability test from the viscosity average molecular weight of the substrate not subjected to the long-term reliability test was determined as a viscosity average molecular weight reduction degree ΔM.

(3) Productivity test of compacted disk (CD) A CD was loaded on an injection molding machine [Meiki Seisakusho M-35BD-DM].
A special mold was attached, a pitted nickel CD stamper was mounted on the mold, and the molding material was automatically fed into the hopper of the molding machine.
The molding was performed continuously at a temperature of 65 ° C. and a mold temperature of 65 ° C. After the start of continuous molding, the number of defective substrates produced increased due to abnormal birefringence and mechanical properties, and the number of molded substrates until the number of defective substrates per 100 units exceeded 10% was determined. The criteria for non-defective product boards are that the birefringence is ± 100 nm or less in a double pass, and the mechanical properties are ± 1.
Within 6 degrees.

(4) DVD productivity test DV was performed on an injection molding machine [Meiki Seisakusho M-35BD-DM].
A mold for exclusive use of D-Video is attached, a stamper for DVD-Video made of nickel with pits is attached to the mold, and a molding material is automatically fed into a hopper of a molding machine, and a cylinder temperature of 370 ° C. Molding was continuously performed at a mold temperature of 115 ° C., and the number of molded sheets was determined in the same manner as in the CD productivity test. The criteria for judging the quality of a production board are as follows: birefringence is ± 100 nm or less in a double pass, mechanical characteristics are ± 0.8 degrees in a radial warp angle, and ±± in a circumferential warp angle.
Within 0.3 degrees.

Example 1 A reactor equipped with a thermometer, a stirrer and a reflux condenser was charged with 219.4 parts of ion-exchanged water and 40% of a 48% aqueous sodium hydroxide solution.
After charging 2 parts, 57.5 parts of 2,2-bis (4-hydroxyphenyl) propane and 0.12 parts of hydrosulfite were dissolved, 181 parts of methylene chloride was added, and the mixture was stirred at 15 to 25 ° C. 28.3 parts of phosgene were blown in over 40 minutes. After completion of the phosgene blowing, 7.2 parts of a 48% aqueous sodium hydroxide solution and 2.42 parts of p-tert-butylphenol were added, stirring was started, and after emulsification, 0.06 part of triethylamine was added.
For 10 minutes to complete the reaction. After the completion of the reaction, the product was diluted with methylene chloride, washed with water, acidified with hydrochloric acid, washed with water, and a stabilizer was added in a kneader having an isolation chamber having a foreign-matter extraction port in a bearing portion, according to the composition shown in Table 1. mixture,
The methylene chloride was evaporated to obtain a powder having a viscosity average molecular weight of 15,000. This powder was added and mixed according to the composition shown in Table 1, and a vented twin-screw extruder [K Kobe Steel Ltd. K
TX-46], melt-kneaded while deaerated at a cylinder temperature of 240 ° C to obtain pellets. Using these pellets, thermal stability test, long-term reliability test, CD and DVD
Was subjected to a productivity test. Table 1 shows the above results.

Examples 2-3 and Comparative Examples 1-5 Polymerization was carried out in the same manner as in Example 1, and Table 1 was prepared in the same manner as in Example 1.
As shown in the composition, a stabilizer and a release agent were added and mixed, and pellets were obtained in the same manner. Using these pellets, a thermal stability test, a long-term reliability test, and a CD and DVD productivity test were performed. Table 1 shows the above results.

From these results, in order to obtain a highly reliable high-density optical disk substrate with good heat resistance, sufficient mold release properties, and improved productivity, regarding the optical polycarbonate resin molding material used for substrate molding, (A) ) 100 parts by weight of an aromatic polycarbonate resin having a viscosity average molecular weight of 10,000 to 22,000, (B) a compound represented by the following general formula (1) (component B-1), and a compound represented by the following general formula (2) (B-2 component), a compound represented by the following general formula (3) (B-3 component), and when the total is 100% by weight, the B-1 component is 10 to 100% by weight. And 0.001 to 0.01 parts by weight of a stabilizer (component (B)) containing 0 to 80% by weight of the B-2 component and 0 to 30% by weight of the B-3 component, and (C) a compound represented by the following general formula (4). Release agent (component C) consisting of the compound represented by 0.00 0.035 shall consist parts it is apparent.

[0070]

[Table 1]

* 1: Tris (2,4-di-tert-
Butylphenyl) phosphite, * 2: Tris (mixed mono, dinonylphenyl) phosphite tetrakis (2,4-di-t-butylphenyl)-
4,4'-biphenylenediphosphonite, tetrakis (2,4-di-t-butylphenyl) -4,3'-biphenylenediphosphonite and tetrakis (2,4-
100: 50: 10 (weight ratio) mixture of di-tert-butylphenyl) -3,3'-biphenylenediphosphonite bis (2,4-di-tert-butylphenyl) -4
-Phenyl-phenylphosphonite and bis (2,4
-Di-tert-butylphenyl) -3-phenyl-phenylphosphonite 5: 3 (weight ratio) mixture Trimethyl phosphate monoglyceride stearic acid

[0072]

The molding material of the present invention is (A) 100 parts by weight of an aromatic polycarbonate resin having a viscosity average molecular weight of 10,000 to 22,000 (component (A)), and (B) represented by the following general formula (1). (B-1 component), a compound represented by the following general formula (2) (B-2 component), and a compound represented by the following general formula (3) (B-3 component). When 100% by weight, the B-1 component is 10 to 10%.
0.001% by weight of a stabilizer (component B) containing 0% by weight, 0 to 80% by weight of component B-2 and 0 to 30% by weight of component B-3.
To 0.01 part by weight and (C) a release agent (component C) comprising a compound represented by the following general formula (4): 0.001 to 0.0
Made of 35 parts by weight, it is possible to maintain high reliability of the substrate and recording film for a long period of time, have good heat resistance, sufficient release property, and improve substrate productivity. And an optical disk substrate. CD-R, CD-RW, M
O, digital versatile discs (DVDs) and other optical discs, especially DVDs, also have a remarkable effect.

Claims (3)

[Claims] (A) a viscosity average molecular weight of 10,000 to
22,000 aromatic polycarbonate resins (component A)
100 parts by weight, (B) a compound represented by the following general formula (1) (component B-1), a compound represented by the following general formula (2) (component B-2), and a compound represented by the following general formula (3) Consisting of the compound represented by the formula (B-3 component), and when the total is 100% by weight, the B-1 component is 10 to 100% by weight, the B-2 component is 0 to 80% by weight, and the B-3 component is 0.001 to 0.01 parts by weight of a stabilizer (component (B)) in a ratio of 0 to 30% by weight and (C) a releasing agent (component (C)) containing a compound represented by the following general formula (4): An optical polycarbonate resin molding material comprising 001 to 0.035 parts by weight. Embedded image [In the formula, Ar ₁ is an aromatic group having a dialkyl substituent, and may be the same or different. Ar ₂ and Ar ₃ are aromatic groups which may have an alkyl substituent, and may be the same or different. R ₁ represents an alkyl group having 1 to 22 carbon atoms and a (t + u) valence, and R ₂ represents an alkyl group having 12 to 22 carbon atoms. t represents 0 or a positive integer, u represents a positive integer, and (t + u) is 1
It has an integer of ~ 6. ] 2. An optical disk substrate formed from the optical polycarbonate resin molding material according to claim 1. 3. A digital versatile resin formed from the optical polycarbonate resin molding material according to claim 1.
Disc (DVD) substrate.