JP2010168420A - Aromatic polycarbonate resin composition and optical molded article formed therefrom - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical disc substrate that exhibits excellent optical properties such as birefringence and the like, correctly transcripts highly dense information signals such as grooves, pits and the like, and exhibits an excellent folding property while having properties as an information recording medium such as flatness, rigidity, less warpage and less wobbling when vibrated, and a resin composition as a material therefor. <P>SOLUTION: The aromatic polycarbonate resin composition comprises essentially (A) an aromatic polycarbonate (polymer A) constituted of a dihydric phenol component consisting essentially of 2,2-bis(4-hydroxyphenyl)propane (component a) and (B) an aromatic polycarbonate copolymer (polymer B) constituted of a dihydric phenol component consisting essentially of (b-1) 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane (component b-1) and (b-2) 4,4'-(m-phenylenediisopropylidene)diphenol and/or 2,2-bis(3-methyl-4-hydroxyphenyl)propane (component b-2) with the ratio of the component b-1 to the component b-2 of 99:1 to 5:95, where the weight ratio of the polymer A to the polymer B (polymer A:polymer B) is 99:1 to 50:50. The optical disc substrate is formed from the composition. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a novel aromatic polycarbonate resin composition and an optical molded article formed therefrom. More specifically, the present invention relates to an optical disk substrate formed from the above resin composition and excellent in bendability and optical characteristics.

  Aromatic polycarbonate resins are optical discs such as compact discs, laser discs, magneto-optical discs, digital video discs, etc., and near-field recording information media characterized by reading and writing signals from the information surface or their substrates. Widely used as a raw material for information recording media.

  These optical information recording media are manufactured by a method in which molten aromatic polycarbonate resin is injected into a mold cavity exposing a stamper on which information signals of pits and grooves are imprinted, and information signals are transferred. Yes.

  The reason why aromatic polycarbonate resin is used in the production of this optical information recording medium is that this resin is excellent in transparency, optical properties, strength, heat resistance, dimensional stability, impact resistance, and moldability. It is because it is also excellent. In particular, when a substrate of an optical information recording medium is manufactured by an injection molding method, a fine concavo-convex pattern (information signal) engraved on a stamper is accurately transferred to the surface of the substrate, and is excellent in warpage and flatness of the substrate. This is because a high-quality optical information recording medium can be obtained.

  On the other hand, optical information recording media in recent years have been different from the original shape of a single CD substrate. For example, in DVD, two substrates having a thickness of 0.6 mm are bonded together using an ultraviolet curable resin. A Blu-ray disc (abbreviated as BD) has a shape in which a cover layer made of an ultraviolet curable resin is formed on the surface of a substrate made of polycarbonate resin, or a cover film is bonded to the substrate.

  However, the ultraviolet light for curing the ultraviolet curable resin is irradiated from the signal reading surface side, and when excessive irradiation is performed, the aromatic polycarbonate resin or the like deteriorates and the molecular weight of the resin decreases. Etc. may be caused.

  In addition, the introduction of video equipment such as car navigation has become widespread in automobiles, and it has become possible to easily watch movies and the like in the car. In particular, the interior of a vehicle in midsummer tends to be in a high temperature and high humidity state, and if the optical information recording medium is left in the vehicle for a long time, the resin used for the substrate deteriorates. Then, there is a problem that the optical information recording medium is easily broken by an impact such as dropping.

  In order to solve this problem, basically, it is effective to increase the molecular weight of the aromatic polycarbonate resin. However, an aromatic polycarbonate resin having a high molecular weight cannot be used as an optical information recording medium because the melt viscosity is lowered and the birefringence of the substrate is increased. There can be considered a manufacturing method in which an optical information recording medium is molded using a molding machine having a high cylinder temperature, but there is a problem that the cooling time becomes long and the substrate productivity deteriorates.

  Also, in the production of conventional optical information recording medium substrates, by setting the cylinder temperature to a lower temperature and shortening the cooling time, it is possible to produce more optical information recording media in a shorter time and improve productivity. The method to do is common. In order to achieve this, even if the cylinder temperature is lowered, the molecular weight of the resin is generally lowered so that the aromatic polycarbonate resin has a sufficient melt viscosity. Therefore, increasing the molecular weight of the resin is not consistent with the conventional manufacturing method, and this problem cannot be solved.

  As an invention of an optical disk substrate using a polycarbonate resin having an adjusted molecular weight, there is an optical disk substrate made of a polycarbonate resin having a viscosity average molecular weight of 14,000 to 15000 containing 0.06-0.09% stearic acid monoglyceride. However, this patent describes the effect of suppressing deformation at the time of molding by specifying the content of the release agent, but there is no description about the strength of the optical disc substrate (Patent Document 1).

  Further, there is an optical disk substrate made of a polycarbonate resin having a viscosity average molecular weight of 10,000 to 17000 and a weight average molecular weight / number average molecular weight of 2.3 or more. However, although it is described that there are few cracks at the time of shaping | molding, the generation | occurrence | production cause and the crack of the board | substrate after long-term use are not clear (patent document 2).

  As another attempt, it has been proposed to use a branched polycarbonate resin as a material for optical moldings such as optical disks, which prevents stringing during molding and improves birefringence, strength, and continuous moldability. However, it is necessary to use a special branched polycarbonate resin (Patent Document 3 and Patent Document 4).

Furthermore, there is a proposal of a method of mixing an ultrahigh molecular weight polycarbonate resin. However, the polycarbonate resin generally used for optical discs has a large molecular weight difference from the ultrahigh molecular weight polycarbonate resin to be mixed, so mixing the ultrahigh molecular weight polycarbonate makes it optically non-uniform, resulting in minute white streaks and molding At times, silver and delamination phenomena occur and mechanical strength is uneven, which is unsuitable for optical applications (Patent Document 5).
Similarly, there are aromatic polycarbonate resin compositions and optical molded articles that have an effect of reducing birefringence, but the strength of the molded articles is not clear (Patent Documents 6 and 7).

Japanese Patent Laid-Open No. 04-168151 JP 2003-162841 A JP 2006-348132 A Japanese Patent Laid-Open No. 60-215019 Japanese Patent Laid-Open No. 04-342760 JP 2000-109669 A Japanese Patent No. 3100862

  An object of the present invention is an information recording medium that is excellent in optical properties such as birefringence, accurately transfers high-density information signals such as grooves and pits, has little flatness, rigidity, and warp, and has little surface vibration during vibration. Another object of the present invention is to provide an optical disc substrate having excellent characteristics and excellent bendability and a resin composition as a material therefor.

  As a result of repeated studies for the above purpose, the present inventors, as a result, (A) an aromatic composed of a dihydric phenol component substantially composed of 2,2-bis (4-hydroxyphenyl) propane (component a). Polycarbonate (polymer A) and (B) (b-1) 1,1-bis (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane (component b-1) and (b-2) 4,4 Aromatic polycarbonate copolymer (polymer B) substantially comprising '-(m-phenylenediisopropylidene) diphenol and / or 2,2-bis (3-methyl-4-hydroxyphenyl) propane (component b-2) It was found that an optical disk substrate formed from an aromatic polycarbonate resin composition substantially consisting of

That is, according to the present invention,
1. (A) an aromatic polycarbonate (polymer A) composed of a dihydric phenol component substantially composed of 2,2-bis (4-hydroxyphenyl) propane (component a), and (B) (b-1) 1 , 1-bis (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane (component b-1) and (b-2) 4,4 ′-(m-phenylenediisopropylidene) diphenol and / or 2 , 2-bis (3-methyl-4-hydroxyphenyl) propane (component b-2), and the ratio of component b-1: component b-2 is 99: 1 to 5:95 in molar ratio. It consists essentially of an aromatic polycarbonate copolymer (Polymer B) composed of a dihydric phenol component, and the ratio of Polymer A to Polymer B is 99: 1 to 50:50 (Polymer A: Poly). An aromatic polycarbonate resin composition characterized by the following:
2. The aromatic polycarbonate resin composition according to item 1, wherein the ratio of component b-1 to component b-2 in polymer B is 80:20 to 10:90 in terms of molar ratio;
3. The aromatic polycarbonate resin composition according to item 1, wherein the viscosity average molecular weight of the polymer A is in the range of 1.45 × 10 ^{4 to} 2.00 × 10 ⁴ ;
4). The aromatic polycarbonate resin composition according to item 1, wherein the specific viscosity of polymer B is in the range of 0.2 to 0.5,
5). An optical molded article formed from the aromatic polycarbonate resin composition according to item 1,
6). An optical disk substrate formed from the aromatic polycarbonate resin composition according to item 1,
7). 7. an optical disk substrate formed by injection compression molding of the aromatic polycarbonate resin composition according to item 1; An optical disc using the optical disc substrate according to item 6 or 7,
Is provided.

  The optical disk substrate of the present invention is excellent in birefringence characteristics, hardly breaks by an impact such as dropping, and is very easy to handle. Moreover, it is easy to store in a long and harsh environment, and has a special effect.

It is the schematic which shows the bending test which sets an optical disk board | substrate to a jig and applies a pressure.

Hereinafter, the present invention will be described in detail.
<Resin composition>
(Polymer A)
The polymer A used in the present invention is an aromatic polycarbonate composed of a dihydric phenol component substantially composed of 2,2-bis (4-hydroxyphenyl) propane (component a). Here, “substantially” means that 90 mol% or more, preferably 95 mol% or more of the total dihydric phenol component is 2,2-bis (4-hydroxyphenyl) propane (component a).

  Examples of dihydric phenol components other than 2,2-bis (4-hydroxyphenyl) propane (component a) 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-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- -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, 1,1-bis (4-hydroxyphenyl) -4-isopropylcyclohexane, 1,1-bis (4-hydroxyphenyl) -3,3,5-trimethyl Cyclohexane, 9,9-bis (4-hydroxyphenyl) fluorene, 9,9-bis {(4-hydroxy-3-methyl) Enyl} fluorene, α, α′-bis (4-hydroxyphenyl) -o-diisopropylbenzene, α, α′-bis (4-hydroxyphenyl) -m-diisopropylbenzene, α, α′-bis (4-hydroxy) Phenyl) -p-diisopropylbenzene, 1,3-bis (4-hydroxyphenyl) -5,7-dimethyladamantane, 4,4′-dihydroxydiphenylsulfone, 4,4′-dihydroxydiphenylsulfoxide, 4,4′- Examples thereof include dihydroxydiphenyl sulfide, 4,4′-dihydroxydiphenyl ketone, 4,4′-dihydroxydiphenyl ether, and 4,4′-dihydroxydiphenyl ester, and these can be used alone or in admixture of two or more.

The viscosity-average molecular weight of the polymer A is preferably in the range of ^{1.45 × 10 4 ~2.00 × 10 4} , more preferably in the range of ^{1.65 × 10 4 ~1.75 × 10 4} . When it is less than 1.45 × 10 ^{4, the} bending resistance of the optical disk substrate after long-term use deteriorates, and it becomes easy to break due to an impact such as dropping. If it exceeds 2.00 × 10 ⁴ , the melt viscosity is lowered and the birefringence of the optical disk substrate is increased, which is not preferable as an optical disk.

This viscosity average molecular weight is calculated from the following formula by measuring the specific viscosity at 20 ° C. of a solution obtained by dissolving 0.7 g of an aromatic polycarbonate resin in 100 ml of methylene chloride.
η _sp /c=[η]+0.45×[η] ² c
[Η] = 1.23 × 10 ⁻⁴ M ^0.83
η _sp : specific viscosity [η]: intrinsic viscosity c: constant (= 0.7)
M: Viscosity average molecular weight

(Polymer B)
The polymer B used in the present invention comprises (b-1) 1,1-bis (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane (component b-1) and (b-2) 4,4. It consists substantially of '-(m-phenylenediisopropylidene) diphenol and / or 2,2-bis (3-methyl-4-hydroxyphenyl) propane (component b-2), and component b-1: component b- 2 is an aromatic polycarbonate copolymer (Polymer B) composed of a dihydric phenol component having a molar ratio of 99: 1 to 5:95. Here, “substantially” means that 90 mol% or more, preferably 95 mol% or more of the total dihydric phenol component is composed of component b-1 and component b-2.

  As described above, the ratio of component b-1: component b-2 is in the range of 99: 1 to 5:95 in molar ratio, preferably in the range of 80:20 to 10:90, and 70:30 to 30:70. The range of is more preferable. An aromatic polycarbonate copolymer within the above range is excellent in melt fluidity, heat resistance, and optical properties.

The specific viscosity of the polymer B is preferably in the range of 0.2 to 0.5, and more preferably in the range of 0.25 to 0.4. When an aromatic polycarbonate copolymer within the above range is used, the optical disk substrate has excellent bending resistance and good optical properties.
The specific viscosity at 20 ° C. of a solution obtained by dissolving 0.7 g of an aromatic polycarbonate copolymer in 100 ml of methylene chloride was measured.

(Composition)
In the present invention, the ratio of the polymer A and the polymer B is 99: 1 to 50:50 (polymer A: polymer B), preferably 97: 3 to 60:40, more preferably 95 by weight ratio. : 5 to 85:15. If the ratio of the polymer A exceeds 99%, the optical characteristics of the optical disk substrate deteriorate, and if it is less than 50%, the substrate becomes brittle and the strength is inferior.

(Production method)
The aromatic polycarbonate resin as the polymer A and the aromatic polycarbonate copolymer as the polymer B of the present invention are each a reaction means known per se for producing an ordinary aromatic polycarbonate resin, for example, a dihydric phenol component and a carbonate precursor. Are reacted by an interfacial polymerization method or a melt polymerization method. Next, basic means for these manufacturing methods will be briefly described.

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

  In producing an aromatic polycarbonate resin by reacting the dihydric phenol and the carbonate precursor by an interfacial polymerization method or a melt polymerization method, a catalyst, a dihydric phenol antioxidant, etc. are used as necessary. Also good.

  A method for producing an aromatic polycarbonate resin by reacting by an interfacial polymerization method or a melt polymerization method is well known. For example, JP-A-2001-225503, JP-A-2003-301099, US Publication No. 2005-106350, and the like can be referred to.

  The reaction by the interfacial polymerization method is usually a reaction between a dihydric phenol and phosgene, and is reacted 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. In order to accelerate the reaction, 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. In the presence of an inert gas, the dihydric phenol and the carbonate ester are mixed with heating, and the resulting alcohol or phenol is mixed. It is carried out by a distilling method. The reaction temperature varies depending on the boiling point of the alcohol or phenol produced, but is usually in the range of 120 to 350 ° C. In the latter stage of the reaction, the system is evacuated to about 10 to 0.1 Torr to facilitate the distillation of the alcohol or phenol produced. The reaction time is usually about 1 to 4 hours.

  Examples of the carbonate ester include esters such as an optionally substituted aryl group having 6 to 10 carbon atoms, an aralkyl group, or an alkyl group having 1 to 4 carbon atoms. Specific examples include diphenyl carbonate, ditolyl carbonate, bis (chlorophenyl) carbonate, m-cresyl carbonate, dinaphthyl carbonate, bis (diphenyl) carbonate, dimethyl carbonate, diethyl carbonate, and dibutyl carbonate. Is preferred.

In addition, a polymerization catalyst can be used to increase the polymerization rate in the melting method. Examples of such a polymerization catalyst include alkali metal compounds such as sodium hydroxide, potassium hydroxide, sodium salt of dihydric phenol, potassium salt, 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, alkali metal and alkaline earth metal alkoxides , Organic acid salts of alkali metals and alkaline earth metals, zinc compounds, boron compounds, aluminum compounds, silicon compounds, germanium compounds, organotin compounds, lead compounds, osmium compounds, antimony compounds Manga Compounds, titanium compounds, usually the esterification reaction, such as zirconium compounds, there can be used a catalyst used in the transesterification reaction. A catalyst may be used independently and may be used in combination of 2 or more types. The amount of these polymerization catalysts used is 1 × 10 ⁻⁸ to 1 × 10 ⁻³ equivalent, preferably 1 × 10 ⁻⁷ to 1 × 10 ⁻³ equivalent, more preferably 1 mol of the raw material dihydric phenol. It is selected in the range of 1 × 10 ^{−6 to} 5 × 10 ⁻⁴ equivalents.

  As the aromatic polycarbonate resin (polymer A and polymer B), monofunctional phenols that are usually used as a terminal terminator can be used in the polymerization reaction. Especially in the case of reactions using phosgene as a carbonate precursor, monofunctional phenols are generally used as end-capping agents for molecular weight control, and the polymers obtained are based on groups based on monofunctional phenols. Since it is blocked by, it is superior in thermal stability compared to other cases.

  The monofunctional phenols are preferably monofunctional phenols represented by the following general formula (1), more preferably alkyl-substituted or phenylalkyl-substituted phenols, particularly preferably p-tert-butylphenol or p-alkyl. Milphenol.

｛式中、Ａは水素原子または炭素数１〜９のアルキル基もしくはフェニルアルキル基（アルキル部分の炭素数１〜９）であり、ｒは１〜５、好ましくは１〜３の整数である。｝

{In formula, A is a hydrogen atom or a C1-C9 alkyl group or a phenylalkyl group (C1-C9 of an alkyl part), r is 1-5, Preferably it is an integer of 1-3. }

  These end groups of monofunctional phenols are desirably introduced into at least 5 mol%, preferably at least 10 mol%, of the total terminal of the resulting aromatic polycarbonate resin. You may use a terminator individually or in mixture of 2 or more types.

  The aromatic polycarbonate resin is produced by a conventionally known method (interfacial polymerization method, melt polymerization method, etc.), and in an organic solvent solution state, the alkaline component in the aromatic polycarbonate resin is extracted and removed using pure water. It is preferable to purify by carrying out a filtration treatment through granulation (granulation) from a solvent solution.

  It is also preferred that the granular raw material after granulation (desolvation) is washed with a poor solvent or non-solvent of the aromatic polycarbonate resin to remove impurities and foreign matters such as low molecular weight components and unreacted components. Examples of the poor solvent or non-solvent for the aromatic polycarbonate resin include ketones such as acetone, aliphatic hydrocarbons such as hexane, and aromatic hydrocarbons such as xylene.

  In the extrusion process (pelletizing process) to obtain a pellet-like aromatic polycarbonate resin for use in injection molding, foreign substances are removed by means such as passing through a sintered metal filter with a filtration accuracy of 10 μm when the aromatic polycarbonate resin is in a molten state. It is preferable to do. In any case, it is important that the aromatic polycarbonate resin before injection molding is not only sodium but also the contents of foreign matters, impurities, solvents, etc. are kept as low as possible.

(Additive)
The polycarbonate resin composition of the present invention includes a heat stabilizer, an antioxidant, a release agent, an ultraviolet absorber, a bluing agent, an antistatic agent, a flame retardant, and a heat ray shielding agent as long as the object of the present invention is not impaired. , Fluorescent dyes (including fluorescent brighteners), pigments, light diffusing agents, reinforcing fillers, other resins and elastomers can be blended.

Examples of the heat stabilizer include a phosphorus heat stabilizer, a sulfur heat stabilizer, and a hindered phenol heat stabilizer.
Examples of the phosphorus-based heat stabilizer include at least one phosphorus compound selected from the group consisting of phosphoric acid, phosphorous acid, phosphonic acid, phosphonous acid, and esters thereof, and these can be blended. The amount of the phosphorus compound is preferably 0.0001 to 0.05 parts by weight, more preferably 0.0005 to 0.02 parts by weight, and more preferably 0.002 to 0.02 parts by weight with respect to 100 parts by weight of the resin composition. 01 parts by weight is particularly preferred. By blending this phosphorus compound, the thermal stability of the resin composition is improved, and a decrease in molecular weight and a deterioration in hue during molding are prevented.

  A specific phosphorus compound is at least one phosphorus compound selected from the group consisting of the following general formulas [2] to [6].

［式中、Ｒ^９〜Ｒ^２２は、それぞれ独立して、水素原子、メチル、エチル、プロピル、イソプロピル、ブチル、イソブチル、ｔｅｒｔ−ブチル、ペンチル、ヘキシル、ヘプチル、オクチル、ノニル、デシル、ドデシル、ヘキサデシル、オクタデシルなどの炭素原子数１〜２０のアルキル基、フェニル、トリル、ナフチルなどの炭素原子数６〜１５のアリール基またはベンジル、フェネチルなどの炭素原子数７〜１８のアラルキル基を表し、また１つの化合物中に２つのアルキル基が存在する場合は、その２つのアルキル基は互いに結合して環を形成していてもよい。］

[Wherein, R ^{9 to} R ²² are each independently a hydrogen atom, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, dodecyl, hexadecyl. Represents an alkyl group having 1 to 20 carbon atoms such as octadecyl, an aryl group having 6 to 15 carbon atoms such as phenyl, tolyl and naphthyl, or an aralkyl group having 7 to 18 carbon atoms such as benzyl and phenethyl; When two alkyl groups are present in one compound, the two alkyl groups may be bonded to each other to form a ring. ]

  Examples of the phosphorus compound represented by the above formula [2] include triphenyl phosphite, trisnonylphenyl phosphite, tris (2,4-di-tert-butylphenyl) phosphite, tridecyl phosphite, and trioctyl phosphite. , Trioctadecyl phosphite, didecyl monophenyl phosphite, dioctyl monophenyl phosphite, diisopropyl monophenyl phosphite, monobutyl diphenyl phosphite, monodecyl diphenyl phosphite, monooctyl diphenyl phosphite, and the like.

  Examples of the phosphorus compound represented by the above formula [3] include tributyl phosphate, trimethyl phosphate, triphenyl phosphate, triethyl phosphate, diphenyl monoorthoxenyl phosphate, dibutyl phosphate, dioctyl phosphate, diisopropyl phosphate and the like. Examples of the phosphorus compound represented by the above formula [4] include tetrakis (2,4-di-tert-butylphenyl) -4,4-diphenylenephosphonite. Examples of the compound represented by the above formula [5] include dimethyl benzenephosphonate, diethyl benzenephosphonate, dipropyl benzenephosphonate and the like. Examples of the compound represented by the above formula [6] include bis (2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite, 2,2-methylenebis (4,6-di-tert-butyl). Phenyl) octyl phosphite, bis (nonylphenyl) pentaerythritol diphosphite, bis (2,4-di-tert-butylphenyl) pentaerythritol diphosphite, distearyl pentaerythritol diphosphite, and the like.

  Among these phosphorus compounds, trisnonylphenyl phosphite, tris (2,4-di-tert-butylphenyl) phosphite, tetrakis (2,4-di-tert-butylphenyl) -4,4-diphenylene Phosphonite is preferably used. Most preferred is tris (2,4-di-tert-butylphenyl) phosphite.

As the sulfur-based heat stabilizer, pentaerythritol-tetrakis (3-laurylthiopropionate), pentaerythritol-tetrakis (3-myristylthiopropionate), pentaerythritol-tetrakis (3-stearylthiopropionate), Examples include dilauryl-3, 3′-thiodipropionate, dimyristyl-3, 3′-thiodipropionate, distearyl-3, 3′-thiodipropionate, and pentaerythritol-tetrakis (3- Lauryl thiopropionate), pentaerythritol-tetrakis (3-myristyl thiopropionate), dilauryl-3, 3'-thiodipropionate, dimyristyl-3, 3'-thiodipropionate. Particularly preferred is pentaerythritol-tetrakis (3-laurylthiopropionate). The thioether compounds are commercially available from Sumitomo Chemical Co., Ltd. as Sumilizer TP-D (trade name), Sumilizer TPM (trade name), and the like, and can be easily used.
As content of the sulfur type heat stabilizer in aromatic polycarbonate resin, 0.001-0.2 weight part is preferable with respect to 100 weight part of aromatic polycarbonate resin composition.

  Examples of the hindered phenol heat stabilizer include triethylene glycol-bis [3- (3-tert-butyl-5-methyl-4-hydroxyphenyl) propionate], 1,6-hexanediol-bis [3- (3 , 5-di-tert-butyl-4-hydroxyphenyl) propionate], pentaerythritol-tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], octadecyl-3- (3 5-di-tert-butyl-4-hydroxyphenyl) propionate, 1,3,5-trimethyl-2,4,6-tris (3,5-di-tert-butyl-4-hydroxybenzyl) benzene, N, N-hexamethylene bis (3,5-di-tert-butyl-4-hydroxy-hydrocinnamide) 3,5-di-tert-butyl-4-hydroxy-benzylphosphonate-diethyl ester, tris (3,5-di-tert-butyl-4-hydroxybenzyl) isocyanurate and 3,9-bis {1,1- And dimethyl-2- [β- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy] ethyl} -2,4,8,10-tetraoxaspiro (5,5) undecane. Octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate is particularly preferably used.

  The content of the hindered phenol heat stabilizer in the aromatic polycarbonate resin is preferably 0.001 to 0.1 parts by weight with respect to 100 parts by weight of the aromatic polycarbonate resin composition.

  To the polycarbonate resin composition of the present invention, an antioxidant generally known for the purpose of antioxidant can be added. Examples thereof include phenolic antioxidants, specifically, for example, triethylene glycol-bis (3- (3-tert-butyl-5-methyl-4-hydroxyphenyl) propionate), 1,6 -Hexanediol-bis (3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate), pentaerythritol-tetrakis (3- (3,5-di-tert-butyl-4-hydroxyphenyl) Propionate), octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate, 1,3,5-trimethyl-2,4,6-tris (3,5-di-tert-butyl) -4-hydroxybenzyl) benzene, N, N-hexamethylenebis (3,5-di-tert-butyl-4- Loxy-hydrocinnamide), 3,5-di-tert-butyl-4-hydroxy-benzylphosphonate-diethyl ester, tris (3,5-di-tert-butyl-4-hydroxybenzyl) isocyanurate, 3.9 -Bis {1,1-dimethyl-2- [β- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy] ethyl} -2,4,8,10-tetraoxaspiro (5 5) Undecane etc. are mentioned. The range of the preferable addition amount of these antioxidants is 0.0001-0.05 weight part with respect to 100 weight part of polycarbonate resin compositions.

  A release agent can be added to the polycarbonate resin composition of the present invention. As the release agent, glycerin monoester is preferably used. Such glycerin monoester is mainly composed of monoester of glycerin and fatty acid, and suitable fatty acid is saturated fatty acid such as stearic acid, palmitic acid, behenic acid, arachidic acid, montanic acid, lauric acid, oleic acid, linoleic acid And unsaturated fatty acids such as sorbic acid, stearic acid, behenic acid and palmitic acid are particularly preferable, and behenic acid is particularly preferable. Those synthesized from natural fatty acids are preferred, most of which are mixtures.

  The content of glycerin monoester is preferably 0.01 to 0.3 parts by weight, more preferably 0.02 to 0.2 parts by weight, and still more preferably 100 parts by weight of the aromatic polycarbonate resin composition. 0.025 to 0.15 parts by weight. When the content is too small, good releasability cannot be obtained, and when the content is too large, discoloration of the molded product is deteriorated.

  The mold release agent can be used in combination with other mold release agents known to those skilled in the art, but even when used in combination, the content of glycerin monoester is preferably 0.01 to 0.3 parts by weight. Preferably it is a component.

  As the UV absorber, at least one UV absorber selected from the group consisting of benzotriazole UV absorbers, benzophenone UV absorbers, triazine UV absorbers, cyclic imino ester UV absorbers, and cyanoacrylates Is preferred.

  Examples of the benzotriazole ultraviolet absorber include 2- (2-hydroxy-5-methylphenyl) benzotriazole, 2- (2-hydroxy-5-tert-octylphenyl) benzotriazole, 2- (2-hydroxy- 3,5-dicumylphenyl) phenylbenzotriazole, 2- (2-hydroxy-3-tert-butyl-5-methylphenyl) -5-chlorobenzotriazole, 2,2'-methylenebis [4- (1,1 , 3,3-tetramethylbutyl) -6- (2N-benzotriazol-2-yl) phenol], 2- (2-hydroxy-3,5-di-tert-butylphenyl) benzotriazole, 2- ( 2-hydroxy-3,5-di-tert-butylphenyl) -5-chlorobenzotriazole, 2- (2-hydroxy 3,5-di-tert-amylphenyl) benzotriazole, 2- (2-hydroxy-5-tert-octylphenyl) benzotriazole, 2- (2-hydroxy-5-tert-butylphenyl) benzotriazole 2- (2-hydroxy-4-octoxyphenyl) benzotriazole, 2,2′-methylenebis (4-cumyl-6-benzotriazolephenyl), 2,2′-p-phenylenebis (1,3- Benzoxazin-4-one), 2- [2-hydroxy-3- (3,4,5,6-tetrahydrophthalimidomethyl) -5-methylphenyl] benzotriazole, and these may be used alone or in combination of two or more. Can be used in a mixture.

  Preferably, 2- (2-hydroxy-5-methylphenyl) benzotriazole, 2- (2-hydroxy-5-tert-octylphenyl) benzotriazole, 2- (2-hydroxy-3,5-dicumyl) Phenyl) phenylbenzotriazole, 2- (2-hydroxy-3-tert-butyl-5-methylphenyl) -5-chlorobenzotriazole, 2,2′-methylenebis [4- (1,1,3,3-tetra Methylbutyl) -6- (2H-benzotriazol-2-yl) phenol], 2- [2-hydroxy-3- (3,4,5,6-tetrahydrophthalimidomethyl) -5-methylphenyl] benzotriazole And more preferably 2- (2-hydroxy-5-tert-octylphenyl) benzotriazole, 2,2 ′ Methylenebis [4- (1,1,3,3-tetramethylbutyl)-6-(2H-benzotriazol-2-yl) phenol].

  Examples of benzophenone-based ultraviolet absorbers include 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-octoxybenzophenone, 2-hydroxy-4-benzyloxybenzophenone, 2-hydroxy-4- Methoxy-5-sulfoxybenzophenone, 2-hydroxy-4-methoxy-5-sulfoxytrihydridolate benzophenone, 2,2'-dihydroxy-4-methoxybenzophenone, 2,2 ', 4,4'-tetrahydroxybenzophenone 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxy-5-sodiumsulfoxybenzophenone, bis (5-benzoyl-4-hydroxy-2- Methoxyphenyl) meta , 2-hydroxy -4-n-dodecyloxy benzoin phenone, 2-hydroxy-4-methoxy-2'-carboxy benzophenone.

  Examples of the triazine ultraviolet absorber include 2- (4,6-diphenyl-1,3,5-triazin-2-yl) -5-[(hexyl) oxy] -phenol, 2- (4,6-bis ( And 2.4-dimethylphenyl) -1,3,5-triazin-2-yl) -5-[(octyl) oxy] -phenol.

  Examples of cyclic imino ester UV absorbers include 2,2′-bis (3,1-benzoxazin-4-one) and 2,2′-p-phenylenebis (3,1-benzoxazin-4-one). 2,2′-m-phenylenebis (3,1-benzoxazin-4-one), 2,2 ′-(4,4′-diphenylene) bis (3,1-benzoxazin-4-one), 2,2 ′-(2,6-naphthalene) bis (3,1-benzoxazin-4-one), 2,2 ′-(1,5-naphthalene) bis (3,1-benzoxazin-4-one) ), 2,2 ′-(2-methyl-p-phenylene) bis (3,1-benzoxazin-4-one), 2,2 ′-(2-nitro-p-phenylene) bis (3,1- Benzoxazin-4-one) and 2,2 ′-(2-chloro-p-ph) Ylene) bis (3,1-benzoxazin-4-one) is illustrated. Among them, 2,2′-p-phenylenebis (3,1-benzoxazin-4-one), 2,2 ′-(4,4′-diphenylene) bis (3,1-benzoxazin-4-one) And 2,2 ′-(2,6-naphthalene) bis (3,1-benzoxazin-4-one) are preferred, especially 2,2′-p-phenylenebis (3,1-benzoxazine-4 -On) is preferred. Such a compound is commercially available from Takemoto Yushi Co., Ltd. as CEi-P (trade name) and can be easily used.

  As the cyanoacrylate ultraviolet absorber, 1,3-bis-[(2′-cyano-3 ′, 3′-diphenylacryloyl) oxy] -2,2-bis [(2-cyano-3,3-diphenyl) Examples include acryloyl) oxy] methyl) propane and 1,3-bis-[(2-cyano-3,3-diphenylacryloyl) oxy] benzene.

  The blending amount of the ultraviolet absorber is preferably 0.01 to 3.0 parts by weight, more preferably 0.02 to 1.0 parts by weight with respect to 100 parts by weight of the aromatic polycarbonate resin composition. More preferably, it is 0.05-0.8 weight part. If it is the range of this compounding quantity, it is possible to provide sufficient weather resistance to a polycarbonate resin molded product according to a use.

Examples of the bluing agent include Macrolex Violet B and Macrolex Blue RR manufactured by Bayer and polysynthremble-RLS manufactured by Clariant. The bluing agent is effective for eliminating the yellow color of the polycarbonate resin particles.
The blending amount of the bluing agent is preferably 0.05 to 1.5 ppm, more preferably 0.1 to 1.2 ppm with respect to the polycarbonate resin composition.

<Optical disk substrate and optical disk>
Optical molded articles formed from the aromatic polycarbonate resin composition of the present invention, particularly optical disk substrates, are digital video disks, DVD-ROMs, DVD-Audios, DVD-Rs, DVD-RAMs and the like represented by digital Versatile disc (DVD) or Blu-ray disc (BD) substrate.

  In manufacturing this optical disk substrate, an injection molding machine (preferably an injection compression molding machine) is used. Although generally used as this injection molding machine, 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 screw is low, and the corrosion resistance and resistance It is preferable to use a material made of a material that exhibits wear.

  As conditions for injection molding, the cylinder temperature is preferably 260 to 450 ° C, more preferably 280 to 380 ° C, and the mold temperature is preferably 50 to 180 ° C, more preferably 70 to 135 ° C. Can be obtained.

  The environment in the molding process is preferably as clean as possible in view of the object of the present invention. It is also important to take into consideration that the material used for molding is sufficiently dried to remove moisture, and that no retention that causes decomposition of the molten resin occurs.

  The optical disk substrate of the present invention comprises a support substrate, a reflective layer formed on the substrate, and a light transmission layer formed on the reflection layer, and laser light is incident from the light transmission layer side. Therefore, it is suitably used as a support substrate for optical disks of a type that performs recording and / or reproduction, such as BD, HD DVD, and a large capacity disk represented by a hologram disk.

  The optical disk substrate of the present invention needs to have a reflective layer and / or a recording layer formed on one side thereof. As a method for producing the inorganic thin films of the recording layer and the reflective layer, various thin film forming methods such as a known vacuum deposition method, PVD method such as sputtering method, or CVD method can be applied. However, it is preferable that the optical disk medium is manufactured under conditions where adhesion to the polymer substrate is particularly high in order not to cause peeling that occurs in a high temperature and high humidity environmental resistance test. For this purpose, sputtering is preferred.

  For example, in the case of a DVD or HD DVD, an adhesive and a light-transmitting second substrate having the same thickness as the first substrate are sequentially formed on a first substrate having a thickness of 0.6 mm, and the first substrate A reflective layer and / or a recording layer are formed on the first substrate side of the second substrate, and information is recorded / reproduced by irradiating laser light from the second substrate side. The second substrate preferably has a transmittance of 80% or more with respect to the wavelength of the laser light, and preferably 90% or more.

  Alternatively, an adhesive and a light-transmitting second substrate having the same thickness as the first substrate are sequentially formed on the first substrate, and the first and second substrates are respectively opposite to each other. The first and second reflective layers and / or the first and second recording layers are formed, and information is recorded and reproduced by irradiating laser light from the second substrate side. The second substrate preferably has a transmittance of 80% or more with respect to the wavelength of the laser light, and preferably 90% or more.

  For example, in the case of BD, a light-transmitting cover layer is formed on the reflective layer and / or the recording layer. The light-transmitting cover layer is made of a material that transmits laser light. As such a material, a polycarbonate resin is preferably used. For example, a polycarbonate sheet formed by a melt extrusion method or a polycarbonate formed by a solution casting method. A casting film is mentioned. As a means for forming the light-transmitting cover layer, for example, a method of bonding a transparent plate such as a sheet or film made of polycarbonate on the recording layer with an adhesive or the like can be mentioned. Furthermore, this light-transmitting cover layer is limited to a thickness of 3 to 200 μm in order to keep coma aberration considerably small. In the case of a Blu-ray Disc (recording type), it is created by forming a light reflecting layer, a recording layer comprising a recording film and a recording film protective film, and a light transmissive cover layer on a 1.1 mm thick substrate. . A plurality of these layers may be formed.

  For the adhesive used when forming the cover film, an ultraviolet curable polymer material may be used as a main component. In this case, the ultraviolet curable polymer material is preferably an acrylate copolymer having an ultraviolet curable group in a side chain, the ultraviolet curable group is an unsaturated group, and the acrylic acid The weight average molecular weight of the ester copolymer is preferably 100,000 or more. For example, a mixture of an acrylate copolymer having an ultraviolet curable group in the side chain and an ultraviolet curable polyfunctional monomer and / or oligomer is used as the ultraviolet curable polymer material. Alternatively, it may be a mixture of an acrylic ester copolymer having no ultraviolet curable group and an ultraviolet curable polyfunctional monomer and / or oligomer. In addition, the adhesive may be mainly composed of a mixture of a polymer component having no ultraviolet curable property and an ultraviolet curable polyfunctional monomer and / or oligomer. In any case, it is preferable that the material exhibits tackiness before curing and has strong adhesiveness and appropriate hardness after curing.

  In the case of a write-once optical disk, the recording film is a recording film on which a irreversible optical characteristic is changed or a concavo-convex shape is formed by irradiation with laser light. A cyanine-based, phthalocyanine-based, azo-based organic dye or the like that changes the optical constant and causes deformation of the substrate due to a volume change is used.

  In the case of a rewritable optical disc, the recording film is a material (phase change recording type) in which a reversible phase structure change between the amorphous state and the crystalline state of the substance caused by laser light irradiation, or perpendicular to the film surface This is a magnetic thin film (magneto-optical recording type) having a magneto-optic effect that has an easy magnetization direction in any direction and can record, reproduce, and erase information by creating an arbitrary inversion magnetic domain. Examples of the phase change recording film include GeSbTe, InSbTe, InSe, InTe, AsTeGe, TeOx-GeSn, TeSeSn, FeTe, SbSeBi, and BiSeGe that are chalcogenide materials. Although it is used, a film made of GeSbTe is preferable because of its stable operation during repeated recording / erasing. Examples of magneto-optical recording films include amorphous alloy thin films of rare earth elements and transition metal elements such as TbFe, TbFeCo, GdTbFe, NdDyFeCo, NdDyTbFeCo, NdFe, PrFe, and CeFe, and those utilizing exchange coupling. A two-layer film, an artificial lattice multilayer film such as Co / Pt or Co / Pd, or a CoPt alloy can be used.

In addition, it is preferable to use a dielectric material as the recording film protective film for sandwiching the recording film. Thereby, the difference in reflectance between the crystalline phase and the amorphous phase as a medium, and the magneto-optical effect can be enhanced. In this case, the dielectric material is preferably a material having a high refractive index n, that is, a material satisfying n ≧ 1.6, more preferably a material satisfying n ≧ 1.8. Eg, SiO-based, _{SiON-based, Ta 2 O 3, TiO 2} , Al 2 O 3, Y 2 O 3, CeO, La 2 O 3, In 2 O 3, GeO, GeO 2, PbO, SnO, SnO 2, _{Bi 2 O 3, TeO 2 WO} 2, WO 3, Sc 2 O 3, ZrO 2 oxide such, TaN, AlN, SiN-based, nitride AlSiN system or the _{like, ZnS, Sb 2 S 3,} CdS, in 2 It is preferable to use a sulfide such as S ₃ , Ga ₂ S ₃ , GeS, SnS ₂ , PbS, Bi ₂ S ₃ , a mixed material thereof, a laminate thereof, or the like as the protective film.

  The light reflecting layer is preferably a material having higher reflectivity than the recording layer with respect to the laser beam of the drive head used for evaluation. Specifically, it is preferable to select a material in which the refractive index n and the extinction coefficient k, which are optical constants at the used laser light wavelength, satisfy n ≦ 3.5 and k ≧ 3.5. More preferably, n ≦ 2.5 and 4.5 ≦ k ≦ 8.5. With a medium manufactured under these conditions, the reproduction signal characteristics can be further improved.

  On the other hand, when recording a signal by heating with laser light, if the thermal conductivity of the light reflecting layer is too high, thermal diffusion is large and a strong laser power is required. For this reason, in order to enable signal recording with a semiconductor laser having a power of 15 mW or less, which is widely used at present, the thermal conductivity of the material used for the light reflection layer is 100 [W / (m · K)] or less. It is more preferable that it is 80 [W / (m · K)] or less.

As a material satisfying such conditions, one or more elements such as Au, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Tc, Re, Ru, Os, Ir, etc. as Al or Ag An alloy to which is added. In these alloys, if the amount of the additive element is less than 0.5 atomic%, the effect of the above-described decrease in heat conduction is small. This is disadvantageous. Therefore, the content of the additive element is preferably within the range of 0.5 to 20 atomic%. In particular, Ti, Zr, Hf, Ta, Cr, and Re are preferable in the specific element group in terms of enhancing durability of the metal reflective film itself. The film thickness range of these reflective layers is 10 to 500 nm, but preferably 30 to 200 nm, particularly in order to suppress the deterioration of the reproduction signal characteristics due to the decrease in reflectance and to enable recording at a laser power of 15 mW. Preferably it is 40-100 nm.
In the case of a read-only optical disc medium, only the light reflecting layer described above is formed on the substrate, but the same materials can be used.

  The optical disk substrate of the present invention has bendability after long-term use. This is an optical disk substrate that not only has excellent bendability at the time of molding, but also has excellent bendability even after long-term use.

Evaluation was based on the following method.
(1) Specific viscosity 0.7 g of polymer B was dissolved in 100 ml of methylene chloride and measured at a temperature of 20 ° C.

(2) Viscosity average molecular weight The specific viscosity at 20 ° C. of a solution prepared by dissolving 0.7 g of polymer A in 100 ml of methylene chloride was measured and calculated from the following formula.
η _sp /c=[η]+0.45×[η] ² c
[Η] = 1.23 × 10 ⁻⁴ M ^0.83
η _sp : specific viscosity [η]: intrinsic viscosity c: constant (= 0.7)
M: Viscosity average molecular weight

(3) ΔR value (optical characteristics)
Using an automatic birefringence measuring apparatus B6DY manufactured by TORYO AT for the optical disk substrate, the difference between the birefringence difference between the normal incidence birefringence of the optical disc substrate and the oblique incidence (30 degrees) birefringence perpendicular to the radial direction of the optical disc substrate The absolute value (ΔR) was measured. The measurement was performed at 8 points in the circumferential direction at each radius in each of the radii 25, 30, 35, 40, 45, 50, and 55 mm, and the average value was used as the measurement value.

(4) Bendability The optical disk substrate was set vertically on a jig as shown in FIG. 1, compressed from a distance of 120 mm to 20 mm at 50 mm / min, and a pressure of 1 MPa was applied. In the process of bending from 120 mm to 20 mm, the substrate cracked was marked with ×, and the substrate that was not broken was marked with ○.

(5) Bendability after wet heat test The optical disk substrate was subjected to wet heat treatment for 200 hours in an environment of 80 ° C. and 85% RH. The bendability of the optical disk substrate after the wet heat treatment was evaluated. The case where the substrate was broken during the bending process was indicated as x, the case where the crack was present was indicated as Δ, and the case where the substrate was not cracked and was not cracked was indicated as ○.

[Example 1]
(Polymer A)
Powdered polycarbonate resin (A1) having 2,1-bis (4-hydroxyphenyl) propane (bisphenol A) having a viscosity average molecular weight of 17,000 obtained by interfacial polymerization from p-tert-butylphenol and phosgene as a repeating unit Prepared.

(Polymer B)
In a reactor equipped with a thermometer, a stirrer, and a reflux condenser, 929.2 parts of ion-exchanged water and 61.3 parts of 48% aqueous sodium hydroxide solution were added, and 1,1-bis (4-hydroxyphenyl) -3, 3, 5 was added. -Trimethylcyclohexane (component b-1: hereinafter sometimes abbreviated as "bisphenol TMC") 39 parts, 4,4 '-(m-phenylenediisopropylidene) diphenol (component b-2: hereinafter "bisphenol M") After dissolving 43.6 parts and hydrosulfite 0.17 parts, 1.51 parts of p-tert-butylphenol and 637.9 parts of methylene chloride were added, and 0.09 part of triethylamine was added. Thereafter, 32.4 parts of phosgene was blown in for 40 minutes at 15 to 25 ° C. with stirring. After completion of the phosgene blowing, 15.6 parts of a 48% aqueous sodium hydroxide solution was added, and the reaction was terminated by stirring at 28 to 33 ° C. for 1 hour. After completion of the reaction, the product is diluted with methylene chloride, washed with water, acidified with hydrochloric acid, washed with water, and when the conductivity of the aqueous phase is almost the same as that of ion-exchanged water, a separation chamber having a foreign matter outlet at the bearing portion. Methylene chloride was evaporated using a kneader provided with a polymer B (B1) having a molar ratio of bisphenol TMC to bisphenol M of 50:50 and a specific viscosity of 0.286.

(Pelletized)
The polymer A (A1) and the polymer B (B1) were blended so that the ratio of the polymer A (A1) and the polymer B (B1) was 90:10 by weight. Further, with respect to 100 parts by weight of this blend, 0.045 parts by weight of stearic acid monoglyceride, 4-Di-tert-butylphenyl) phosphite (0.003 parts by weight) was added, and the strand was extruded by a 30 mm single screw extruder at a temperature range of 240 to 280 ° C. and pelletized with a cutter.

(Manufacture of optical disk substrates and optical disks)
The obtained pellets were dried at 120 ° C. for 5 hours, then using an injection compression molding machine (SD-40E manufactured by Sumitomo Heavy Industries, Ltd.), a mold having a cavity thickness of 1.2 mm and a diameter of 120 mm, and a stamper for a CD-ROM substrate. The optical disk substrate was molded at a cylinder set temperature of 370 ° C., a mold temperature of 75 ° C., a clamping force of 280 PMa, and a molding cycle of 5 seconds. Thereafter, a reflective film was formed on the optical disk substrate to obtain a CD-ROM.

[Example 2]
(Polymer B)
In Example 1, the ratio of bisphenol TMC to bisphenol M is 40:60 in terms of molar ratio and the specific viscosity is 0.292 except that 31.2 parts of bisphenol TMC and 52.2 parts of bisphenol M are used. A certain polymer B (B2) was obtained. Next, an optical disk substrate and a CD-ROM were obtained in the same manner as in Example 1 except that the polymer B (B2) was used as the polymer B.

[Example 3]
(Polymer B)
In Example 1, the ratio of bisphenol TMC to bisphenol M was 60:40 in terms of molar ratio and the specific viscosity was 0.275, except that 46.8 parts of bisphenol TMC and 34.9 parts of bisphenol M were used. A certain polymer B (B3) was obtained. Next, an optical disk substrate and a CD-ROM were obtained in the same manner as in Example 1 except that the polymer B (B3) was used as the polymer B.

[Example 4]
An optical disk substrate and a CD-ROM were obtained in the same manner as in Example 1 except that the weight ratio of the polymer A (A1) and the polymer B (B1) was 50:50.

[Example 5]
(Polymer B)
In Example 1, the ratio of bisphenol TMC and bisphenol M is 10:90 in molar ratio and the specific viscosity is 0.286, except that 7.8 parts of bisphenol TMC and 78.4 parts of bisphenol M are used. A certain polymer B (B4) was obtained. Next, an optical disk substrate and a CD-ROM were obtained in the same manner as in Example 1, except that the ratio of the polymer A (A1) to the polymer B (B4) was 50:50 by weight.

[Comparative Example 1]
0.045 parts by weight of stearic acid monoglyceride, tris (based on 100 parts by weight of a granular polycarbonate resin having a repeating unit of bisphenol A having a viscosity average molecular weight of 17,000 obtained by interfacial polymerization from p-tert-butylphenol and phosgene 2,4-di-tert-butylphenyl) phosphite was added in an amount of 0.003 part by weight, and the pellets were extruded by a 30 mm single screw extruder at a temperature range of 240 to 280 ° C. and pelletized by a cutter, An optical disk substrate and a CD-ROM were obtained in the same manner as in Example 1.

[Example 6]
Example 1 except that as the polymer A, a granular polycarbonate resin (A2) containing bisphenol A having a viscosity average molecular weight of 15,000 obtained by interfacial polymerization from p-tert-butylphenol and phosgene as a repeating unit is used. An optical disk substrate and a CD-ROM were obtained by the same method.

[Example 7]
Example 2 except that the polymer A is a granular polycarbonate resin (A2) having a repeating unit of bisphenol A having a viscosity average molecular weight of 15,000 obtained by interfacial polymerization from p-tert-butylphenol and phosgene. An optical disk substrate and a CD-ROM were obtained by the same method.

[Example 8]
Example 3 except that as the polymer A, a granular polycarbonate resin (A2) having a repeating unit of bisphenol A having a viscosity average molecular weight of 15,000 obtained from p-tert-butylphenol and phosgene by an interfacial polymerization method is used. An optical disk substrate and a CD-ROM were obtained by the same method.

[Example 9]
An optical disk substrate and a CD-ROM were obtained in the same manner as in Example 1 except that blending was performed so that the ratio of polymer A (A2) to polymer B (B1) was 50:50 by weight.

[Example 10]
An optical disk substrate and a CD-ROM were obtained in the same manner as in Example 1 except that the weight ratio of the polymer A (A2) and the polymer B (B4) was 50:50.

[Comparative Example 2]
0.045 parts by weight of stearic acid monoglyceride, tris (based on 100 parts by weight of a granular polycarbonate resin having a viscosity average molecular weight of 15,000 bisphenol A obtained by interfacial polymerization from p-tert-butylphenol and phosgene. 2,4-di-tert-butylphenyl) phosphite was added in an amount of 0.003 part by weight, and the pellets were extruded by a 30 mm single screw extruder at a temperature range of 240 to 280 ° C. and pelletized by a cutter, An optical disk substrate and a CD-ROM were obtained in the same manner as in Example 1.

[Comparative Example 3]
0.045 parts by weight of stearic acid monoglyceride, tris (based on 100 parts by weight of a granular polycarbonate resin having a repeating unit of bisphenol A having a viscosity average molecular weight of 13,500 obtained by interfacial polymerization from p-tert-butylphenol and phosgene 2,4-di-tert-butylphenyl) phosphite was added in an amount of 0.003 part by weight, and the pellets were extruded by a 30 mm single screw extruder at a temperature range of 240 to 280 ° C. and pelletized by a cutter, An optical disk substrate and a CD-ROM were obtained in the same manner as in Example 1.

The following is clear from the examples and comparative examples.
Examples 1 to 5 have good bendability and a good ΔR value as compared with Comparative Example 1.
Examples 6 to 10 have good bendability and a good ΔR value as compared with Comparative Example 2.
In Comparative Example 3, the ΔR value was good, but it was cracked in the bending test. There is a problem in bendability.

  The resin composition of the present invention is useful as a molding material for optical molded articles, particularly optical disk substrates.

1. Jig 2. 2. Optical disk substrate Width between jigs (120mm)
4). Width between jigs (20mm)

Claims (8)

  (A) an aromatic polycarbonate (polymer A) composed of a dihydric phenol component substantially composed of 2,2-bis (4-hydroxyphenyl) propane (component a), and (B) (b-1) 1 , 1-bis (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane (component b-1) and (b-2) 4,4 ′-(m-phenylenediisopropylidene) diphenol and / or 2 , 2-bis (3-methyl-4-hydroxyphenyl) propane (component b-2), and the ratio of component b-1: component b-2 is 99: 1 to 5:95 in molar ratio. It consists essentially of an aromatic polycarbonate copolymer (polymer B) composed of a dihydric phenol component, and the ratio of polymer A to polymer B is 99: 1 to 50:50 (polymer A: polymer). The aromatic polycarbonate resin composition which is a mer B).   The aromatic polycarbonate resin composition according to claim 1, wherein the ratio of the component b-1 to the component b-2 of the polymer B is 80:20 to 10:90 in molar ratio. The aromatic polycarbonate resin composition according to claim 1, wherein the viscosity average molecular weight of the polymer A is in the range of 1.45 × 10 ^{4 to} 2.00 × 10 ⁴ .   The aromatic polycarbonate resin composition according to claim 1, wherein the specific viscosity of the polymer B is in the range of 0.2 to 0.5.   An optical molded article formed from the aromatic polycarbonate resin composition according to claim 1.   An optical disk substrate formed from the aromatic polycarbonate resin composition according to claim 1.   An optical disk substrate formed by injection compression molding of the aromatic polycarbonate resin composition according to claim 1.   An optical disk using the optical disk substrate according to claim 6.

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