JP2001342337A - Optical molded material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polycarbonate molding material which does not cause decomposition, burning, silver streaking or the like and can precisely transcribe a mold profile and is free from optical strain for practical purposes and, in addition, can obtain optical disc having high long-term reliability. SOLUTION: The optical molding material is obtained by incorporating (A) 0.01-0.1 pt.wt. partial or whole ester to be derived from a 10-22C monovalent fatty acid and a polyhydric alcohol, (B) 0.001-0.05 pt.wt. trimethyl phosphate, and (C) 0.001-0.01 pt.wt. phosphorous acid ester into 100 pts.wt. polycarbonate resin, and an optical disc substrate is formed of this optical molding material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to an optical molding material. More specifically, the present invention relates to a molding material which is excellent in moldability at high temperatures, heat stability, and hydrolysis resistance and has high long-term reliability, and is particularly suitable for optical disc substrates.

[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. Of these, compact discs and laser discs are read-only (Read Only Memory:
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 (Recorda) on which arbitrary information can be written by a user.
ble) type optical disk, and a magneto-optical disk and a phase change type disk are RAMs (Random Access Meshes) in which arbitrary information can be repeatedly written.
memory) type optical disc. That is, the R-type optical disc is formed of a write-once recording layer on a transparent substrate, the optical characteristics of which are irreversibly changed by irradiation of a laser beam, or the uneven shape is formed. 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.

[0004] A magneto-optical disk is a rewritable optical disk in which information can be repeatedly written and erased by a user.
It is formed by forming a perpendicular magnetization film having a magneto-optical effect (for example, the Kerr effect) such as an Fe—Co amorphous alloy thin film. 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 phase-change disk exhibits a crystalline state in an initial state and changes its phase 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 degree of signal modulation due to multiple interference. In many cases, a four-layer structure in which an Al reflective layer is laminated thereon is adopted. In addition, as the dielectric layer, a silicon nitride film, a Zn—SiO ₂ mixed film, or the like is used. By the way, 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. This DVD has a diameter of 120 mm, which is the same as a CD, and records video information equivalent to one movie, so that it 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.

[0008] 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 disks include a single-sided bonded optical disk using only one surface thereof and a double-sided bonded optical disk using both surfaces thereof. For such optical disk substrates, polycarbonate resins having excellent moldability, strength, light transmittance, moisture resistance, and the like are often used.

In such optical applications, it is particularly important that optical distortion is small and pit transferability is good. In order to obtain a molded article having such low birefringence and good transferability, good fluidity and mold release properties are required during molding. In order to improve the fluidity during molding, a polycarbonate resin having a viscosity average molecular weight of about 20,000 or less is used. However, the resin temperature during molding is still 3
A high temperature of 10 to 400 ° C. is required, and a reduction in molecular weight due to depolymerization and coloring due to thermal deterioration are likely to occur. Therefore, excellent heat resistance is required for the polycarbonate resin.

Heretofore, attempts have been made to blend various compounds as a method for improving the thermal stability of a polycarbonate resin. Phosphorous esters such as triphenyl phosphite and tricresyl phosphite are generally used as these compounds. Since such a phosphite has a considerably high vapor pressure at the processing temperature of a polycarbonate resin, if it is used in an amount capable of imparting sufficient thermal stability, a problem arises that bubbles and so-called silver wires easily enter the obtained molded product. I do. As an improved technique, an optical composition using a polyhydric alcohol fatty acid partial ester and a phosphite in a polycarbonate resin has been proposed (Japanese Patent Publication No. 1-2).
No. 3498). Further, an optical composition improved in hydrolyzability by adding phosphorous acid has been proposed (Japanese Patent Application Laid-Open No. 10-1998).
No. 60247). As described above, recently, with the increase in the recording capacity of the optical disc, a substrate having high long-term reliability in addition to high transferability and low birefringence has been required, and in the proposed composition, For high temperature molding,
The effect is not enough, especially in terms of long-term reliability.

[0011]

SUMMARY OF THE INVENTION An object of the present invention is to provide an optical element having excellent moldability at high temperatures, thermal stability and long-term reliability.
It is an object of the present invention to provide a polycarbonate resin molding material particularly suitable for an optical disk substrate. The present inventors have made intensive studies to achieve the above object, and as a result, (A) a partial ester derived from a specific fatty acid and a polyhydric alcohol;
By using (B) trimethyl phosphate and (C) phosphite in a specific amount in combination, it is possible to provide a polycarbonate resin with excellent moldability, heat stability and hydrolysis resistance even at high temperatures. Thus, the present invention has been completed.

[0012]

According to the present invention, there is provided a composition comprising (A) a portion derived from a monohydric fatty acid having 10 to 22 carbon atoms and a polyhydric alcohol, and
Or 0.01 to 0.1 parts by weight of all esters, (B) 0.001 to 0.05 parts by weight of trimethyl phosphate, and (C) 0.001 to 0.01 parts by weight of phosphite. It relates to an optical molding material.

The component (A) used in the present invention includes, for example, myristic acid, palmitic acid, stearic acid, oleic acid, behenic acid, fatty acids of sulfurized fish oil and the like having 10 to 22 carbon atoms.
Or a mixture of monohydric fatty acids and partial and / or total esters derived from polyhydric alcohols such as ethylene glycol, glycerin and pentaerythritol. The esterification rate can be in the range of 10 to 80%, preferably 20 to 60%, where the esterification rate when the polyhydric alcohol is completely esterified is 100%. The amount of component (A) used is in the range of 0.01 to 0.1 parts by weight based on 100 parts by weight of the polycarbonate resin. If the amount is less than 0.01 part by weight, the mold releasability at the time of melt molding is deteriorated, and the molded article becomes fogged or optically distorted due to mold release distortion. Due to the thermal decomposition, silver strips are formed on the molded product, and stains are generated on the substrate and the stamper.

The component (B) is trimethyl phosphate, which is used in an amount of 0.001 to 0.05 parts by weight based on 100 parts by weight of the polycarbonate resin. If the amount is less than 0.001 part by weight, the obtained molded article will be colored,
If the amount is more than 0.05 parts by weight, silver strips are formed on the molded article during melt molding, and the boiling water resistance is lowered.

The component (C) is a phosphite, for example, bis [2,4-di-tert-butyl-6-methylphenyl] ethyl phosphite, bis (2,4-di-te).
(rt-butylphenyl) pentaerythritol diphosphite, distearyl-pentaerythritol diphosphite, diphenyl-pentaerythrityl-diphosphite, tris (2,4-di-tert-butylphenyl) phosphite and the like. Especially Tris (2,4
-Di-tert-butylphenyl) phosphite is preferred. The phosphite as the component (C) improves the thermal stability of the polycarbonate resin at high temperatures,
The effect of improving the hue of the molded article by interaction with the component (A) is exhibited. The amount used is polycarbonate resin 1.
0.001 to 0.01 parts by weight based on 00 parts by weight.
If the amount is less than 0.001 part by weight, it is difficult to obtain a sufficient effect of improving heat stability and hue. If the amount is more than 0.01 part by weight, boiling water resistance is reduced and silver stripes are formed.

The optical molding material of the present invention can be prepared by any mixing method, and the order of mixing may be arbitrary. Particularly, a melt mixing method using an extruder is the most preferable method. Further, additives such as an ultraviolet absorber and a coloring agent can be added to the molding material of the present invention as needed.

Next, the polycarbonate resin and the method for producing the same according to the present invention will be described. The polycarbonate resin used in the present invention is usually obtained by reacting a dihydric phenol with a carbonate precursor 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, 1,1-
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-diisopropylbenzene, 1,3-bis (4-hydroxyphenyl) -5,7-dimethyladamantane, 4,4′-dihydroxydiphenylsulfone, 4,4 ′ -Dihydroxydiphenyl sulphoxide, 4,4'-dihydroxydiphenyl sulfide, 4,4'-dihydroxydiphenyl ketone, 4,4'-dihydroxydiphenyl ether and 4,4'-dihydroxydiphenyl ester; These can be used in combination.

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 or haloformate is 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, a terminal stopper, a dihydric phenol antioxidant and the like are used as necessary. Is also good. 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, In addition, 2 of the obtained polycarbonate resin
It may be a mixture of more than one species.

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.

In such a polymerization reaction, a terminal stopper is usually used. Monofunctional phenols can be used as such a terminal stopper. Monofunctional phenols are commonly used as molecular terminators for molecular weight control, and the resulting polycarbonate resins are capped by groups based on monofunctional phenols, so that Excellent heat stability. Such a monofunctional phenol is generally a phenol or a lower alkyl-substituted phenol, and may be a monofunctional phenol represented by the following general formula (T-1).

[0022]

Embedded image (In the formula, A is a hydrogen atom, a linear or branched alkyl group having 1 to 9 carbon atoms or a phenyl-substituted alkyl group, and r is an integer of 1 to 5, preferably 1 to 3.)

Specific examples of the above monofunctional phenols include phenol, p-tert-butylphenol, p-cumylphenol and isooctylphenol.

Further, other monofunctional phenols include:
Phenols or benzoic acid chlorides having a long-chain alkyl group or an aliphatic polyester group as a substituent, or long-chain alkyl carboxylic acid chlorides can be used. When blocked, these not only function as a terminal terminator or a molecular weight regulator, but also improve the melt flowability of the resin, not only facilitate the molding process, but also reduce the physical properties as a substrate, especially the water absorption of the resin. And the effect of reducing the birefringence of the substrate is preferably used. Among them, the following general formula (T-2)
And phenols having a long-chain alkyl group represented by (T-3) as a substituent are preferably used.

[0025]

Embedded image (Wherein X is -RO-, -R-CO-O- or -R
—O—CO—, wherein R is a single bond or 1 carbon atom
Represents a divalent aliphatic hydrocarbon group of 10 to 10, preferably 1 to 5, and n represents an integer of 10 to 50. )

As the substituted phenols of the formula (T-2), those having n of 10 to 30, especially 10 to 26, are preferred, and specific examples thereof include decylphenol, dodecylphenol, tetradecylphenol and hexadecylphenol. Octadecylphenol, eicosylphenol, docosylphenol and triacontylphenol.

As the substituted phenols of the formula (T-3), compounds wherein X is -R-CO-O- and R is a single bond are suitable, and n is 10-30, especially 10-10. 26
Are preferred, and specific examples thereof include, for example, decyl hydroxybenzoate, dodecyl hydroxybenzoate,
Examples include tetradecyl hydroxybenzoate, hexadecyl hydroxybenzoate, eicosyl hydroxybenzoate, docosyl hydroxybenzoate and triacontyl hydroxybenzoate. These terminating agents are used in at least 5 terminals relative to all terminals of the obtained polycarbonate resin.
Molar%, preferably at least 10 mol%, is desirably introduced at the terminal, and the terminal terminator may be used alone or in combination of two or more.

The reaction by the melt polymerization method is usually a transesterification reaction between a dihydric phenol and a carbonate ester, and is carried out in the presence of an inert gas or in the absence of an active gas.
It is carried out by a method in which a polyhydric phenol and a carbonate ester are mixed while heating, and the resulting alcohol or phenol is distilled. The reaction temperature varies depending on the boiling point of the alcohol or phenol to be formed, etc.
It is in the range of 20-350 ° C. In the late stage of the reaction,
The pressure is reduced to about 0.1 Torr (about 1,330 Pa to 13 Pa) to facilitate the distillation of the generated alcohol or phenol. The reaction time is usually about 1 to 4 hours.

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

A polymerization catalyst may 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 catalysts may be used alone or in combination of two or more. The use amount of these polymerization catalysts is preferably 1 × 10 ⁻⁸ to 1 × 10 ⁻³ equivalents, more preferably 1 × 10 ^{−7 to} 5 × 10 ⁻⁴ equivalents, per 1 mol of the starting dihydric phenol. Selected by range.

In order to reduce the number of phenolic terminal groups in the polymerization reaction, for example, bis (chlorophenyl) carbonate, bis (bromophenyl) carbonate, bis (nitrophenyl) carbonate may be used later or after completion of the polycondensation reaction. , Bis (phenylphenyl)
Carbonate, chlorophenylphenyl carbonate,
It is preferable to add compounds such as bromophenylphenyl carbonate, nitrophenylphenyl carbonate, phenylphenyl carbonate, methoxycarbonylphenylphenyl carbonate, and ethoxycarbonylphenylphenyl carbonate. Of these, 2-chlorophenylphenyl carbonate, 2-methoxycarbonylphenylphenyl carbonate and 2-ethoxycarbonylphenylphenyl carbonate are preferred, and 2-methoxycarbonylphenylphenyl carbonate is particularly preferred.

The molecular weight of the polycarbonate resin is preferably 10,000 to 22,000, more preferably 12,000 to 20,000, and more preferably 13,000 to 22,000 in terms of viscosity average molecular weight (M).
000 to 18,000 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 referred to in the present invention is obtained by inserting the specific viscosity (η _SP ) obtained from a solution obtained by dissolving 0.7 g of a polycarbonate resin in 100 mL of methylene chloride at 20 ° C. into 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 Polycarbonate resin After being manufactured by the above-mentioned conventionally known methods (interfacial polymerization method, melt polymerization method, etc.), a filtration treatment is performed in a solution state, and a granular raw material after granulation (desolvation) is heated, for example, to acetone or the like. It is preferable to remove impurities and foreign substances such as low molecular weight components and unreacted components by washing with a poor solvent. Further, in the extrusion step (pelleting step) of obtaining a pellet-like polycarbonate resin for use in injection molding, a filtration accuracy of 10 μm in a molten state.
It is preferable to remove foreign matter by passing through a sintered metal filter of m. In any case, it is necessary to minimize the content of foreign materials, impurities, solvents and the like in the raw material resin before injection molding.

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, adhesion to the resin as a cylinder or screw is low, and corrosion resistance and resistance It is preferable to use one made of a material exhibiting abrasion.
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.

The optical disk substrate thus formed is
Compact disc (hereinafter, sometimes referred to as CD), CD-R, MO, MD-MO, etc., and further, digital video disc (hereinafter, sometimes referred to as DVD), DVD-ROM, DVD-video, DVD −
It is used as a substrate for high-density optical disks represented by R, DVD-RAM and the like.

[0036]

The present invention will be described below with reference to examples and comparative examples. In addition, the part in an Example is a weight part, and evaluated by the following method. (1) Heat resistance: A flat plate of 50 × 50 × 2 mm was temporarily stopped during molding at an injection molding machine [V17 / 65 type manufactured by Nippon Steel Works Co., Ltd.] at a cylinder temperature of 380 ° C. and a molding cycle of 45 seconds. After being retained for one minute, the molding was restarted, and the L value, a value, and b value of the flat plate before and after the retention were measured using a color difference meter Z-1 manufactured by Nippon Denshoku.
0001DP

[0037]

(Equation 1)

[Wherein L ₁ , a ₁ and b ₁ are L values before residence, a
L ₂ , a ₂ , b ₂ are the L values after residence, a
Value, b value. ] To determine the color difference (ΔE). ΔE
The larger the value, the worse the color and the poorer the heat resistance. (2) White defect: using a pellet, an optical disk substrate (diameter 120 mm, thickness 1.2 mm) was processed at a cylinder temperature of 380 ° C and a mold temperature of 75 ° C by a disk molding machine [DISK3M III manufactured by Sumitomo Heavy Industries, Ltd.]. After molding, 25 substrates were left for 168 hours under the conditions of a temperature of 80 ° C. and a humidity of 85%, and the average value when the number of microhydrolysates (spherical white defects) in the substrates was counted using an optical microscope . (3) Appearance: The optical disk substrate was visually observed to determine the presence or absence of defects (dirt, silver, etc. due to mold release failure).

Examples 1 to 7 and Comparative Examples 1 to 3 An aqueous alkali solution of bisphenol A and methylene chloride
Phosgene was introduced with stirring at 5 ° C., then p-tert-butylphenol as a molecular weight regulator and triethylamine as a catalyst were added, and the mixture was reacted for 3 hours. The methylene chloride layer of the reaction mixture was washed repeatedly with water, and then washed with a solvent. The slurry-like polycarbonate resin obtained by removing
Dry under reduced pressure at 10 ° C for 4 hours, viscosity average molecular weight 15,000
Was obtained. Then this powder 1
To 00 parts by weight, the fatty acid ester, trimethyl phosphate and phosphite in the amounts shown in Table 1 were added and mixed.
The thread was extruded by a 30 mm extruder in a temperature range of 270 ° C. into pellets by an extrusion cutter, and the molding was evaluated. Table 1 shows the evaluation results. The symbols representing the fatty acid ester, trimethyl phosphate and phosphite in Table 1 are as follows.

Fatty acid ester A1-1: Monoglyceride stearate (Rikemar S-100A manufactured by Riken Vitamin) A1-1: Monoglyceride stearate (Exel T-95 manufactured by Kao) A2-1: Pentaerythritol tetrastearate (Roxyl manufactured by Henkel Japan) VPG861) A2-1: pentaerythritol tetrastearate (manufactured by Riken Vitamin Co., Ltd. Rikesuta EW-440A) trimethyl phosphate B: trimethyl phosphate (Daihachi chemical industry Ltd. TMP) phosphite C1-1: tri (2,4 t-butylphenyl) phosphite (Adeka Stab 2112 manufactured by Asahi Denka) C1-2: tri (2,4-t-butylphenyl) phosphite (Inrga manufactured by Ciba Specialty Chemicals)
fos-168) C1-3: Tri (2,4-t-butylphenyl) phosphite (Sumilyzer P-16 manufactured by Sumitomo Chemical) C2: Trisnolylphenyl phosphite (TNP manufactured by Yokkaichi Gosei)

[0041]

[Table 1]

Subsequently, write-once optical information recording media were prepared using the molding materials of Examples 1 to 7, and evaluated. Resin temperature 32 using a disk molding machine [M-35BD-DM made by Meiki Seisakusho] equipped with a stamper having a spiral pregroove formed on the surface.
A substrate having a thickness of 1.2 mm was formed at 0 ° C., a mold temperature of 100 ° C., a sprue temperature of 70 ° C., and a cooling time of 7.0 seconds. The pregroove has a width of 0.5 μm, a depth of 250 nm, and a pitch of 1.6.
μm. Then, per 10 ml of diacetone alcohol, 1,1'-dibutyl-3,3,3 ', 3'-tetramethyl-4,5,4', 5'-dibenzoindodicarbocyanine iodide (Nippon Sensitive Dye NK-32 manufactured by
51) Using a solution in which 480 mg was dissolved, a coating film was formed on the above-formed CD-R substrate by spin coating to form a recording film having a thickness of 70 nm. Balzers sputtering apparatus CUBE LITE is placed on the recording film.
A gold film was formed to have a thickness of 50 nm. Furthermore, a protective film SD-1700 made by Dainippon Ink was applied thereon with a protective film of 50 nm using a coating machine made by Sony and an ultraviolet curing device to obtain a write-once optical information recording medium. Each disc was recorded and reproduced, and it was confirmed that the characteristics were excellent.

Further, a bonding type write-once optical information recording medium was produced and evaluated using each of the materials of Examples 1 to 7.

The surface has a width of 0.32 μm, a depth of 100 nm,
Using a disk molding machine [M-35BD-DM made by Meiki Seisakusho] equipped with a stamper on which a spiral pregroove having a pitch of 0.74 μm is formed, a resin temperature of 380 ° C. and a mold temperature of 130 ° C. , Sprue temperature 1
A substrate having a thickness of 0.6 mm was formed at a temperature of 00 ° C. and a cooling time of 10.0 seconds. Next, a trimethyl cyanine dye NK-4285
(Manufactured by Japan Photochromic Research Laboratories) and NK-4270:
75, and the mixture is mixed with 2,2,3,3-tetrafluoro-1-propanol (TFC, manufactured by Tokyo Chemical Industry Co., Ltd.).
P) was dissolved at 3% by weight, and the solution was applied to the surface of the substrate by spin coating to form a 110 nm-thick recording film made of a photosensitive dye. On this recording film, an Au film having a thickness of 80 nm was formed on the entire surface of the substrate in a region from φ44 mm to φ117 mm by a sputtering method, and a reflection film was formed. Also, an ultraviolet curable resin S is formed on the reflective film.
D-1700 (manufactured by Dainippon Ink and Chemicals, Inc.) was spin-coated, and the coating was irradiated with ultraviolet light to be cured. This recording film, the substrate provided with the gold reflective film and the protective film, and a transparent substrate having no such film and a thickness of 0.6 mm were bonded together by an ultraviolet curing type bonding apparatus. The laminating apparatus was laminated under standard conditions using UV-curable adhesive DVD-003 (manufactured by Nippon Kayaku) by FA-YG23 manufactured by Matsushita Electric Industrial Co., Ltd. to obtain a lamination type write-once optical information recording medium. Then, each disk was recorded and reproduced, and it was confirmed that the characteristics were excellent.

Further, using the materials of Examples 1 to 7, CD-Audio, CD-ROM and DVD-R
When OM was manufactured and evaluated, all showed good reproduction characteristics. CD-RWs were also manufactured and evaluated, and all showed good recording / reproducing characteristics.

[0046]

The molding material of the present invention has a temperature of 310 to 400.degree.
Even when molded at high temperatures, molds are accurately transferred without decomposing, burning, silver stripes, etc., and molded products with long-term reliability without optical distortion that may cause practical problems are obtained. Can be Therefore, substrates for optical disks, various lenses, prisms,
It is useful for optical applications such as Fresnel lenses and is particularly excellent as a substrate for optical disks.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G02B 1/04 G02B 1/04 // B29C 45/00 B29C 45/00 B29K 69:00 B29K 69:00 B29L 17:00 B29L 17:00 F term (reference) 4F071 AA50 AA81 AC10 AC15 AE05 AE11 AH12 BA01 BB05 BC01 4F206 AA28 AH38 AH79 JA07 JQ81 4J002 CG011 CG021 CG031 EH046 EH056 EW047 EW068 EW088 FD0 166

Claims (4)

[Claims] [Claim 1] 100 parts by weight of a polycarbonate resin,
(A) Part and / or all esters derived from monohydric fatty acids having 10 to 22 carbon atoms and polyhydric alcohols 0.0
1 to 0.1 part by weight, (B) trimethyl phosphate 0.001 to
0.05 parts by weight and (C) phosphite 0.001
An optical molding material which is blended with 0.01 to 0.01 parts by weight. 2. The optical molding material according to claim 1, wherein the phosphite (C) is tris (2,4-di-tert-butylphenyl) phosphite. 3. The optical molding material according to claim 1, wherein the polycarbonate resin has a molecular weight of 13,000 to 18,000 as represented by a viscosity average molecular weight. 4. An optical disk substrate formed from the optical resin molding material according to claim 1.