KR102642651B1 - Polycarbonate resin composition for optical component and optical component - Google Patents

Abstract

Based on 100 parts by mass of polycarbonate resin (A), 0.1 to 4 parts by mass of polyalkylene glycol (B) and 0.005 to 0.5 parts by mass of phosphorus-based stabilizer (C) are contained, and polyalkylene glycol (B) is tetra. The amount of the component having a weight average molecular weight (Mw) of 400 or less as measured in polystyrene conversion by gel permeation chromatography using hydrofuran as a solvent is less than 1.0 mass%, and the number average molecular weight (Mn) determined from the terminal hydroxyl value is less than 1.0% by mass. A polycarbonate resin composition for optical components, characterized in that it is 700 to 2600.

Description

Polycarbonate resin composition for optical components and optical components {POLYCARBONATE RESIN COMPOSITION FOR OPTICAL COMPONENT AND OPTICAL COMPONENT}

The present invention relates to a polycarbonate resin composition for optical components and optical components, and more specifically, to a polycarbonate resin composition for optical components that has good color and very little gas generation and mold contamination during molding, and a polycarbonate resin composition for molding the same. It's about optical components.

Liquid crystal display devices used in personal computers, mobile phones, etc. are equipped with planar light source devices in order to meet the requirements for thinner, lighter, more energy-saving, and higher-definition devices. In addition, this planar light source device is provided with a light guide plate with a wedge-shaped cross-section or a flat light guide plate with one side having a uniformly inclined surface for the purpose of guiding incident light uniformly and efficiently to the liquid crystal display side. . There are also cases where a light scattering function is provided by forming an uneven pattern on the surface of the light guide plate.

Such a light guide plate is obtained by injection molding of a thermoplastic resin, and the above-described uneven pattern is provided by transferring the uneven portions formed on the surface of the insert mold. Conventionally, light guide plates have been molded from resin materials such as polymethyl methacrylate (PMMA), but recently, display devices that project clearer images are required, and the temperature inside the device tends to rise due to heat generated near the light source. Therefore, it is being replaced by polycarbonate resin material with higher heat resistance.

Polycarbonate resin has excellent mechanical properties, thermal properties, electrical properties, and weather resistance, but its light transmittance is lower than PMMA, etc., so when a cotton light source body is composed of a light guide plate and light source made of polycarbonate resin, there is a problem of low luminance. There is. In addition, in recent years, there has been a demand for reducing the chromaticity difference between the light entering portion of the light guide plate and the location away from the light entering portion, but polycarbonate resin has the problem of being prone to yellowing compared to PMMA.

Patent Document 1 describes a method of improving light transmittance and brightness by adding an acrylic resin and an alicyclic epoxy compound, and Patent Document 2 describes a method of improving brightness by modifying the polycarbonate resin terminal and increasing the transferability of the uneven portion to the light guide plate. Patent Document 3 proposes a method of improving luminance by introducing a copolyester carbonate having an aliphatic segment and improving the transferability.

However, in the method of Patent Document 1, the color is improved by adding an acrylic resin, but the light transmittance and brightness cannot be increased because it becomes cloudy. Although the transmittance may be improved by adding an alicyclic epoxy compound, the color is poor. The improvement effect is not recognized. In the case of Patent Document 2 and Patent Document 3, the effect of improving fluidity and transferability can be expected, but there is a drawback that heat resistance is reduced.

On the other hand, it is known to mix polyethylene glycol or poly(2-methyl)ethylene glycol with thermoplastic resins such as polycarbonate resin, and in Patent Document 4, a γ-ray irradiation-resistant polycarbonate resin containing this is described in Patent Document 5. describes a thermoplastic resin composition with excellent antistatic properties and excellent surface appearance mixed with PMMA and the like.

And, in Patent Document 6, a proposal is made to improve transmittance and color by mixing polyalkylene glycol composed of a straight-chain alkyl group. Improvements in transmittance and yellowing degree (yellow index: YI) are observed by mixing polytetramethylene ether glycol.

However, especially in recent years, in various portable terminals such as smartphones and tablet-type terminals, optical components such as light guide plates are becoming thinner or larger at a remarkable speed, and light guide plate molding requires high barrel temperature and high-speed injection. It is becoming. Along with this, the gas generated during molding increases and mold contamination tends to occur, which is a problem. Therefore, the resin composition used for these moldings is required to have not only excellent optical properties but also minimal mold contamination during injection molding at high temperatures.

Japanese Patent Publication No. 11-158364 Japanese Patent Publication No. 2001-208917 Japanese Patent Publication No. 2001-215336 Japanese Patent Publication No. 1-22959 Japanese Patent Publication No. 9-227785 Japanese Patent Publication No. 5699188

The present invention was made in consideration of the above-mentioned circumstances, and its purpose is to produce polymolecular weight modifier resin for optical parts that does not impair the original properties of the polymolecular weight modifier resin at all, has good color, and has very little gas generation and mold contamination during molding. The object is to provide carbonate resin compositions and optical components.

In order to achieve the above-described problem, the present inventor conducted extensive studies and found that polyalkylene glycol containing less than 1.0 mass% of components with a weight average molecular weight (Mw) of 400 or less was added to the polycarbonate resin along with a phosphorus-based stabilizer. It was found that by mixing in a specific amount, a polycarbonate resin composition for optical parts that has good color and very little gas generation and mold contamination during molding can be obtained, leading to the completion of the present invention.

The present invention relates to the following polycarbonate resin composition for optical components and optical components.

[1] Containing 0.1 to 4 parts by mass of polyalkylene glycol (B) and 0.005 to 0.5 parts by mass of phosphorus-based stabilizer (C), based on 100 parts by mass of polycarbonate resin (A),

Polyalkylene glycol (B) contains less than 1.0 mass% of components with a weight average molecular weight (Mw) of 400 or less, as measured in polystyrene conversion by gel permeation chromatography using tetrahydrofuran as a solvent, and has a terminal hydroxyl group. A polycarbonate resin composition for optical components, characterized in that the number average molecular weight (Mn) calculated from is 700 to 2600.

[2] The polycarbonate resin composition for optical components according to [1] above, wherein the polyalkylene glycol (B) has a tetramethylene ether unit.

[3] The polycarbonate resin composition for optical components according to [2] above, wherein the molar ratio of the tetramethylene ether unit of the polyalkylene glycol (B) is 50 mol% or more.

[4] The polycarbonate for optical components according to any one of [1] to [3] above, further comprising 0.0005 to 0.2 parts by mass of an epoxy compound (D) based on 100 parts by mass of the polycarbonate resin (A). Resin composition.

[5] An optical component molded from the polycarbonate resin composition according to any one of [1] to [4] above.

The polycarbonate resin composition of the present invention does not impair the original properties of the polycarbonate resin at all, generates little gas during molding, has very little mold contamination, and can provide optical parts with good color.

Fig. 1 is a top view of a drop-shaped mold used for evaluation of mold contamination in the examples.

Hereinafter, the present invention will be described in detail by showing embodiments, examples, etc.

In addition, in this specification, “~” is used to mean that the numerical values described before and after it are included as the lower limit and the upper limit, unless otherwise specified.

The polycarbonate resin composition for optical components of the present invention contains 0.1 to 4 parts by mass of polyalkylene glycol (B) and 0.005 to 0.5 parts by mass of phosphorus stabilizer (C), based on 100 parts by mass of polycarbonate resin (A). do,

Polyalkylene glycol (B) contains less than 1.0 mass% of components with a weight average molecular weight (Mw) of 400 or less, as measured in polystyrene conversion by gel permeation chromatography using tetrahydrofuran as a solvent, and has a terminal hydroxyl group. It is characterized in that the number average molecular weight (Mn) calculated from is 700 to 2600.

Hereinafter, each component, optical component, etc. constituting the polycarbonate resin composition of the present invention will be described in detail.

[Polycarbonate resin (A)]

There is no limitation on the type of polycarbonate resin used in the present invention, and one type of polycarbonate resin may be used, or two or more types may be used together in any combination and in any ratio.

Polycarbonate resin is a polymer with a basic structure having a carbonate bond represented by the formula: -[-O-X-O-C(=O)-]-.

In the formula, X is generally a hydrocarbon, but in order to provide various properties,

In addition, polycarbonate resin can be classified into aromatic polycarbonate resin in which the carbon directly bonded to the carbonate bond is aromatic carbon, and aliphatic polycarbonate resin in which the carbon directly bonded to the carbonate bond is each an aliphatic carbon, but either can be used. Among them, aromatic polycarbonate resin is preferable from the viewpoint of heat resistance, mechanical properties, electrical properties, etc.

There is no limitation on the specific type of polycarbonate resin, but examples include polycarbonate polymers formed by reacting a dihydroxy compound and a carbonate precursor. At this time, in addition to the dihydroxy compound and carbonate precursor, a polyhydroxy compound, etc. may be reacted. Additionally, a method of reacting carbon dioxide with cyclic ether using carbon dioxide as a carbonate precursor may also be used. Additionally, the polycarbonate polymer may be linear or branched. In addition, the polycarbonate polymer may be a single polymer consisting of one type of repeating unit, or may be a copolymer having two or more types of repeating units. At this time, the copolymer can be selected from various copolymer forms, such as random copolymer and block copolymer. In addition, such polycarbonate polymer usually becomes a thermoplastic resin.

Among the monomers that serve as raw materials for aromatic polycarbonate resin, examples of aromatic dihydroxy compounds include:

Dihydroxybenzenes such as 1,2-dihydroxybenzene, 1,3-dihydroxybenzene (i.e., resorcinol), and 1,4-dihydroxybenzene;

Dihydroxybiphenyls such as 2,5-dihydroxybiphenyl, 2,2'-dihydroxybiphenyl, and 4,4'-dihydroxybiphenyl;

2,2'-dihydroxy-1,1'-binaphthyl, 1,2-dihydroxynaphthalene, 1,3-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, 1,6-di Dihydroxynaphthalene, such as hydroxynaphthalene, 2,6-dihydroxynaphthalene, 1,7-dihydroxynaphthalene, and 2,7-dihydroxynaphthalene;

2,2'-dihydroxydiphenyl ether, 3,3'-dihydroxydiphenyl ether, 4,4'-dihydroxydiphenyl ether, 4,4'-dihydroxy-3,3'- dihydroxydiaryl ethers such as dimethyldiphenyl ether, 1,4-bis(3-hydroxyphenoxy)benzene, and 1,3-bis(4-hydroxyphenoxy)benzene;

2,2-bis(4-hydroxyphenyl)propane (i.e. bisphenol A),

1,1-bis(4-hydroxyphenyl)propane,

2,2-bis(3-methyl-4-hydroxyphenyl)propane,

2,2-bis(3-methoxy-4-hydroxyphenyl)propane,

2-(4-hydroxyphenyl)-2-(3-methoxy-4-hydroxyphenyl)propane,

1,1-bis(3-tert-butyl-4-hydroxyphenyl)propane,

2,2-bis(3,5-dimethyl-4-hydroxyphenyl)propane,

2,2-bis(3-cyclohexyl-4-hydroxyphenyl)propane,

2-(4-hydroxyphenyl)-2-(3-cyclohexyl-4-hydroxyphenyl)propane,

α,α'-bis(4-hydroxyphenyl)-1,4-diisopropylbenzene,

1,3-bis[2-(4-hydroxyphenyl)-2-propyl]benzene,

Bis(4-hydroxyphenyl)methane,

Bis(4-hydroxyphenyl)cyclohexylmethane,

Bis(4-hydroxyphenyl)phenylmethane,

Bis(4-hydroxyphenyl)(4-propenylphenyl)methane,

Bis(4-hydroxyphenyl)diphenylmethane,

Bis(4-hydroxyphenyl)naphthylmethane,

1,1-bis(4-hydroxyphenyl)ethane,

1,1-bis(4-hydroxyphenyl)-1-phenylethane,

1,1-bis(4-hydroxyphenyl)-1-naphthylethane,

1,1-bis(4-hydroxyphenyl)butane,

2,2-bis(4-hydroxyphenyl)butane,

2,2-bis(4-hydroxyphenyl)pentane,

1,1-bis(4-hydroxyphenyl)hexane,

2,2-bis(4-hydroxyphenyl)hexane,

1,1-bis(4-hydroxyphenyl)octane,

2,2-bis(4-hydroxyphenyl)octane,

4,4-bis(4-hydroxyphenyl)heptane,

2,2-bis(4-hydroxyphenyl)nonane,

1,1-bis(4-hydroxyphenyl)decane,

1,1-bis(4-hydroxyphenyl)dodecane,

bis(hydroxyaryl)alkanes such as;

1,1-bis(4-hydroxyphenyl)cyclopentane,

1,1-bis(4-hydroxyphenyl)cyclohexane,

1,1-bis(4-hydroxyphenyl)-3,3-dimethylcyclohexane,

1,1-bis(4-hydroxyphenyl)-3,4-dimethylcyclohexane,

1,1-bis(4-hydroxyphenyl)-3,5-dimethylcyclohexane,

1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane,

1,1-bis(4-hydroxy-3,5-dimethylphenyl)-3,3,5-trimethylcyclohexane,

1,1-bis(4-hydroxyphenyl)-3-propyl-5-methylcyclohexane,

1,1-bis(4-hydroxyphenyl)-3-tert-butyl-cyclohexane,

1,1-bis(4-hydroxyphenyl)-4-tert-butyl-cyclohexane,

1,1-bis(4-hydroxyphenyl)-3-phenylcyclohexane,

1,1-bis(4-hydroxyphenyl)-4-phenylcyclohexane,

bis(hydroxyaryl)cycloalkanes such as;

9,9-bis(4-hydroxyphenyl)fluorene,

Cardo structure-containing bisphenols such as 9,9-bis(4-hydroxy-3-methylphenyl)fluorene;

4,4'-dihydroxydiphenyl sulfide,

Dihydroxydiaryl sulfides such as 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfide;

4,4'-dihydroxydiphenyl sulfoxide,

Dihydroxydiaryl sulfoxides such as 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfoxide;

4,4'-dihydroxydiphenylsulfone,

Dihydroxydiarylsulfones such as 4,4'-dihydroxy-3,3'-dimethyldiphenylsulfone;

etc. can be mentioned.

Among these, bis(hydroxyaryl)alkanes are preferable, and among them, bis(4-hydroxyphenyl)alkanes are preferable, and 2,2-bis(4-hydroxyphenyl) is particularly preferred in terms of impact resistance and heat resistance. ) Propane (i.e. bisphenol A) is preferred.

Additionally, one type of aromatic dihydroxy compound may be used, or two or more types may be used together in any combination and ratio.

In addition, examples of monomers that serve as raw materials for aliphatic polycarbonate resin include:

Ethane-1,2-diol, propane-1,2-diol, propane-1,3-diol, 2,2-dimethylpropane-1,3-diol, 2-methyl-2-propylpropane-1,3- Alkanediols such as diol, butane-1,4-diol, pentane-1,5-diol, hexane-1,6-diol, and decane-1,10-diol;

Cyclopentane-1,2-diol, cyclohexane-1,2-diol, cyclohexane-1,4-diol, 1,4-cyclohexanedimethanol, 4-(2-hydroxyethyl)cyclohexanol, 2 Cycloalkanediols such as ,2,4,4-tetramethyl-cyclobutane-1,3-diol;

Glycols such as ethylene glycol, 2,2'-oxydiethanol (i.e., diethylene glycol), triethylene glycol, propylene glycol, and spiroglycol;

1,2-benzenedimethanol, 1,3-benzenedimethanol, 1,4-benzenedimethanol, 1,4-benzenediethanol, 1,3-bis(2-hydroxyethoxy)benzene, 1,4 -Bis(2-hydroxyethoxy)benzene, 2,3-bis(hydroxymethyl)naphthalene, 1,6-bis(hydroxyethoxy)naphthalene, 4,4'-biphenyldimethanol, 4,4 Aralkyl such as '-biphenyldiethanol, 1,4-bis(2-hydroxyethoxy)biphenyl, bisphenol A bis(2-hydroxyethyl)ether, and bisphenol S bis(2-hydroxyethyl)ether. diols;

1,2-epoxyethane (i.e. ethylene oxide), 1,2-epoxypropane (i.e. propylene oxide), 1,2-epoxycyclopentane, 1,2-epoxycyclohexane, 1,4-epoxycyclohexane, Cyclic ethers such as 1-methyl-1,2-epoxycyclohexane, 2,3-epoxynorbornane, and 1,3-epoxypropane; etc. can be mentioned.

Among the monomers that serve as raw materials for polycarbonate resin, carbonate precursors such as carbonyl halide and carbonate ester are used. Additionally, one type of carbonate precursor may be used, or two or more types may be used together in any combination and ratio.

Specific examples of the carbonyl halide include phosgene; Haloformates, such as the bischloroformate form of a dihydroxy compound, and the monochloroformate form of a dihydroxy compound, etc. are mentioned.

Specific examples of carbonate ester include diaryl carbonates such as diphenyl carbonate and ditolyl carbonate; Dialkyl carbonates such as dimethyl carbonate and diethyl carbonate; Biscarbonate forms of dihydroxy compounds, monocarbonate forms of dihydroxy compounds, and carbonate forms of dihydroxy compounds such as cyclic carbonates can be mentioned.

Method for producing polycarbonate resin

The method for producing polycarbonate resin is not particularly limited, and any method can be adopted. Examples include interfacial polymerization, melt transesterification, pyridine method, ring-opening polymerization of cyclic carbonate compounds, and solid-phase transesterification of prepolymers.

Hereinafter, among these methods, particularly preferred ones will be described in detail.

Interfacial polymerization

First, the case where polycarbonate resin is manufactured by the interfacial polymerization method will be described.

In the interfacial polymerization method, the pH is usually maintained at 9 or higher in the presence of an organic solvent and an aqueous alkaline solution inert to the reaction, and a dihydroxy compound and a carbonate precursor (preferably phosgene) are reacted in the presence of a polymerization catalyst. Polycarbonate resin is obtained by performing interfacial polymerization under Additionally, a molecular weight regulator (end stopper) may be present in the reaction system as needed, and an antioxidant may be present to prevent oxidation of the dihydroxy compound.

The dihydroxy compound and carbonate precursor are as described above. Moreover, among carbonate precursors, it is preferable to use phosgene, and the method in which phosgene is used is especially called the phosgene method.

Examples of organic solvents inert to the reaction include chlorinated hydrocarbons such as dichloromethane, 1,2-dichloroethane, chloroform, monochlorobenzene, and dichlorobenzene; Aromatic hydrocarbons such as benzene, toluene, and xylene; etc. can be mentioned. Additionally, one type of organic solvent may be used, or two or more types may be used together in any combination and ratio.

Examples of the alkaline compounds contained in the aqueous alkaline solution include alkali metal compounds and alkaline earth metal compounds such as sodium hydroxide, potassium hydroxide, lithium hydroxide, and sodium bicarbonate. Among them, sodium hydroxide and potassium hydroxide are preferred. . Additionally, one type of alkaline compound may be used, or two or more types may be used together in any combination and ratio.

There is no limitation on the concentration of the alkaline compound in the aqueous alkaline solution, but it is usually used at 5 to 10% by mass in order to control the pH in the aqueous alkaline solution for reaction to 10 to 12. In addition, for example, when injecting phosgene, in order to control the pH of the water phase to be 10 to 12, preferably 10 to 11, the molar ratio of the bisphenol compound and the alkali compound is usually 1:1.9 or more, especially 1:1. It is preferably 2.0 or more, and usually 1:3.2 or less, especially 1:2.5 or less.

Examples of the polymerization catalyst include aliphatic tertiary amines such as trimethylamine, triethylamine, tributylamine, tripropylamine, and trihexylamine; Alicyclic tertiary amines such as N,N'-dimethylcyclohexylamine and N,N'-diethylcyclohexylamine; Aromatic tertiary amines such as N,N'-dimethylaniline and N,N'-diethylaniline; Quaternary ammonium salts such as trimethylbenzylammonium chloride, tetramethylammonium chloride, and triethylbenzylammonium chloride; pyridine; guanine; Salts of guanidine; etc. can be mentioned. In addition, one type of polymerization catalyst may be used, or two or more types may be used together in any combination and ratio.

Examples of the molecular weight regulator include aromatic phenol having a monovalent phenolic hydroxyl group; Aliphatic alcohols such as methanol and butanol; Mercaptan; Phthalic imide and the like can be mentioned, but aromatic phenol is especially preferable. Specific examples of such aromatic phenols include alkyl group-substituted phenols such as m-methyl phenol, p-methyl phenol, m-propyl phenol, p-propyl phenol, p-tert-butyl phenol, and p-long chain alkyl substituted phenol; Vinyl group-containing phenols such as isopropanylphenol; Phenol containing an epoxy group; Carboxyl group-containing phenols such as o-hydroxybenzoic acid and 2-methyl-6-hydroxyphenylacetic acid; etc. can be mentioned. In addition, one type of molecular weight regulator may be used, or two or more types may be used together in any combination and ratio.

The amount of the molecular weight regulator used is usually 0.5 mol or more, preferably 1 mol or more, and usually 50 mol or less, preferably 30 mol or less, per 100 mol of the dihydroxy compound. By keeping the usage amount of the molecular weight regulator within this range, the thermal stability and hydrolysis resistance of the resin composition can be improved.

During the reaction, the order of mixing the reaction substrate, reaction medium, catalyst, additives, etc. is arbitrary as long as the desired polycarbonate resin is obtained, and an appropriate order may be set arbitrarily. For example, when phosgene is used as a carbonate precursor, the molecular weight regulator can be mixed at any time between the reaction between the dihydroxy compound and phosgene (phosgenation) and the start of the polymerization reaction.

In addition, the reaction temperature is usually 0 to 40°C, and the reaction time is usually several minutes (for example, 10 minutes) to several hours (for example, 6 hours).

Melt transesterification method

Next, a case where polycarbonate resin is produced by a melt transesterification method will be described.

In the melt transesterification method, for example, a transesterification reaction of a carbonic acid diester and a dihydroxy compound is performed.

The dihydroxy compound is as described above.

On the other hand, examples of diester carbonates include dialkyl carbonates such as dimethyl carbonate, diethyl carbonate, and di-tert-butyl carbonate; diphenyl carbonate; and substituted diphenyl carbonates such as ditolyl carbonate. Among them, diphenyl carbonate and substituted diphenyl carbonate are preferred, and diphenyl carbonate is particularly preferred. In addition, diester carbonate may be used alone, or two or more types may be used together in any combination and ratio.

The ratio of the dihydroxy compound and diester carbonate is arbitrary as long as the desired polycarbonate resin is obtained, but it is preferable to use an equimolar amount or more of the diester carbonate per mole of the dihydroxy compound, and in particular, use 1.01 mole or more. It is more desirable to do so. Additionally, the upper limit is usually 1.30 mol or less. By setting it to such a range, the amount of terminal hydroxyl groups can be adjusted to a desirable range.

In polycarbonate resin, the amount of terminal hydroxyl groups tends to have a great influence on thermal stability, hydrolysis stability, color tone, etc. For this reason, the amount of terminal hydroxyl groups may be adjusted as necessary by any known method. In the transesterification reaction, the mixing ratio of the carbonic acid diester and the aromatic dihydroxy compound is usually; By adjusting the degree of pressure reduction during the transesterification reaction, etc., a polycarbonate resin with the amount of terminal hydroxyl groups adjusted can be obtained. In addition, through this operation, the molecular weight of the polycarbonate resin obtained can usually be adjusted.

When adjusting the amount of terminal hydroxyl groups by adjusting the mixing ratio of diester carbonate and dihydroxy compound, the mixing ratio is as above.

Additionally, a more active adjustment method includes a method of separately mixing an end stopper during reaction. Examples of the end stopper at this time include monohydric phenols, monohydric carboxylic acids, and diester carbonates. In addition, one type of terminal stopping agent may be used, or two or more types may be used together in any combination and ratio.

When producing polycarbonate resin by the melt transesterification method, a transesterification catalyst is usually used. Any transesterification catalyst can be used. Among them, it is preferable to use, for example, an alkali metal compound and/or an alkaline earth metal compound. Additionally, for example, basic compounds such as basic boron compounds, basic phosphorus compounds, basic ammonium compounds, and amine compounds may be used together. In addition, one type of transesterification catalyst may be used, and two or more types may be used together in arbitrary combinations and ratios.

In the melt transesterification method, the reaction temperature is usually 100 to 320°C. Additionally, the pressure during reaction is usually a reduced pressure of 2 mmHg or less. As a specific operation, a melt polycondensation reaction may be performed under the above conditions while removing by-products such as aromatic hydroxy compounds.

The melt polycondensation reaction can be performed by either a batch method or a continuous method. When carried out in a batch manner, the order of mixing the reaction substrate, reaction medium, catalyst, additives, etc. is arbitrary as long as the desired aromatic polycarbonate resin is obtained, and an appropriate order may be set arbitrarily. However, considering the stability of the polycarbonate resin, etc., it is preferable to carry out the melt polycondensation reaction continuously.

In the melt transesterification method, a catalyst deactivator may be used as needed. As a catalyst deactivator, any compound that neutralizes the transesterification catalyst may be used. Examples include sulfur-containing acidic compounds and their derivatives. In addition, one type of catalyst deactivator may be used, or two or more types may be used together in any combination and ratio.

The amount of catalyst deactivator used is usually 0.5 equivalent or more, preferably 1 equivalent or more, and usually 10 equivalent or less, preferably 5 equivalent or less, based on the alkali metal or alkaline earth metal contained in the transesterification catalyst. . Furthermore, with respect to polycarbonate resin, it is usually 1 ppm or more, and is usually 100 ppm or less, preferably 20 ppm or less.

The molecular weight of the polycarbonate resin (A) is preferably 10,000 to 26,000, more preferably 10,500, in terms of viscosity average molecular weight (Mv) converted from the solution viscosity measured at a temperature of 25°C using methylene chloride as a solvent. or more, more preferably 11,000 or more, especially 11,500 or more, most preferably 12,000 or more, more preferably 24,000 or less, and even more preferably 20,000 or less. By setting the viscosity average molecular weight to the lower limit of the above range or more, the mechanical strength of the polycarbonate resin composition of the present invention can be further improved, and by setting the viscosity average molecular weight to the upper limit of the above range or less, the fluidity of the polycarbonate resin composition of the present invention Deterioration can be suppressed and improved, and molding processability can be increased to facilitate thin-walled molding processing.

Additionally, two or more types of polycarbonate resins having different viscosity average molecular weights may be mixed and used, and in this case, polycarbonate resins whose viscosity average molecular weights are outside the above preferred range may be mixed.

In addition, the viscosity average molecular weight [Mv] is obtained by using methylene chloride as a solvent, using an Ubbelohde viscometer to determine the intrinsic viscosity [η] (unit dl/g) at a temperature of 25°C, and using Schnell's viscosity equation, i.e. , η = 1.23 × 10 ^-4 This means the value calculated from Mv ^0.83 . In addition, the intrinsic viscosity [η] is a value calculated by measuring the specific viscosity [η _sp ] at each solution concentration [C] (g/dl) and using the following formula.

The terminal hydroxyl group concentration of the polycarbonate resin is arbitrary and can be appropriately selected and determined, but is usually 1,000 ppm or less, preferably 800 ppm or less, and more preferably 600 ppm or less. As a result, the residence heat stability and color tone of the polycarbonate resin can be further improved. Moreover, the lower limit is usually 10 ppm or more, preferably 30 ppm or more, and more preferably 40 ppm or more, especially for polycarbonate resin produced by the melt transesterification method. Thereby, a decrease in molecular weight can be suppressed and the mechanical properties of the resin composition can be further improved.

In addition, the unit of terminal hydroxyl group concentration is the mass of terminal hydroxyl group relative to the mass of polycarbonate resin expressed in ppm. The measurement method is colorimetric determination using the titanium tetrachloride/acetic acid method (method described in Macromol. Chem. 88 215 (1965)).

Polycarbonate resin is not limited to polycarbonate resin alone (polycarbonate resin alone is not limited to containing only one type of polycarbonate resin, but contains, for example, multiple types of polycarbonate resins having different monomer compositions and molecular weights). It may be used in the sense that includes the following aspects), or it may be used in combination with an alloy (mixture) of polycarbonate resin and another thermoplastic resin. Furthermore, for example, for the purpose of further improving flame retardancy and impact resistance, polycarbonate resin may be used as a copolymer with an oligomer or polymer having a siloxane structure; copolymers with monomers, oligomers, or polymers having phosphorus atoms for the purpose of further improving thermal oxidation stability or flame retardancy; For the purpose of improving thermal oxidation stability, copolymers with monomers, oligomers or polymers having a dihydroxyanthraquinone structure; oligomers or copolymers with polymers having an olefinic structure such as polystyrene to improve optical properties; Polyester resin oligomers or copolymers with polymers for the purpose of improving chemical resistance; etc., may be composed as a copolymer mainly composed of polycarbonate resin.

Additionally, in order to improve the appearance and fluidity of the molded product, the polycarbonate resin may contain a polycarbonate oligomer. The viscosity average molecular weight [Mv] of this polycarbonate oligomer is usually 1,500 or more, preferably 2,000 or more, and is usually 9,500 or less, preferably 9,000 or less. In addition, the polycarbonate oligomer contained is preferably 30% by mass or less of the polycarbonate resin (including polycarbonate oligomer).

In addition, the polycarbonate resin may be not only a virgin raw material, but also a polycarbonate resin recycled from a used product (so-called material recycled polycarbonate resin).

However, the recycled polycarbonate resin is preferably 80% by mass or less, and more preferably 50% by mass or less of the polycarbonate resin. This is because the recycled polycarbonate resin is likely to be subject to deterioration such as thermal deterioration or aging deterioration, and therefore, if such polycarbonate resin is used in an amount exceeding the above range, there is a possibility that the color and mechanical properties may deteriorate.

[Polyalkylene glycol (B)]

The polycarbonate resin composition for optical components of the present invention contains less than 1.0 mass% of components having a weight average molecular weight (Mw) of 400 or less, as measured in terms of polystyrene by gel permeation chromatography using tetrahydrofuran as a solvent. It contains a polyalkylene glycol (B) having a number average molecular weight (Mn) determined from the terminal hydroxyl value of 700 to 2600.

By containing such polyalkylene glycol (B), optical parts can be obtained that have good color and have very little gas generation and mold contamination during molding. If the amount of the component with a weight average molecular weight (Mw) of 400 or less is 1.0 mass% or more, mold adhesion during injection molding increases and clogging of gas vents, etc. occurs. The amount of the component with a weight average molecular weight (Mw) of 400 or less is preferably less than 0.8 mass%, more preferably less than 0.6 mass%, and even less than 0.5 mass%.

The weight average molecular weight (Mw) of polyalkylene glycol (B) is measured by gel permeation chromatography (GPC) using tetrahydrofuran as a solvent, and is determined by comparison with a calibration curve using standard polystyrene and conversion. The amount (mass %) of the component with Mw of 400 or less is defined as a ratio calculated by dividing the area of the portion with Mw of 400 or less in the obtained GPC spectrum curve by the area of the entire spectrum curve. The specific details of the GPC measurement are as described in the Examples.

Polyalkylene glycol (B) in which the amount of components with a weight average molecular weight (Mw) of 400 or less is less than 1.0 mass% can be prepared by removing the components with Mw of 400 or less by washing with water or alcohol, or by using sulfuric acid. It can also be obtained by selectively extracting low molecular weight components by adding an aqueous solution containing them. It is also possible to select and use commercially available products.

The number average molecular weight (Mn) of the polyalkylene glycol (B) is determined from the terminal hydroxyl value as described above and is 700 to 2,600, but is preferably 800 or more, more preferably 900 or more, and is preferably 800 or more. Preferably it is 2,200 or less, more preferably 2,000 or less, even more preferably 1,800 or less, and particularly preferably 1,600 or less. If it exceeds the upper limit of the above range, it is undesirable because compatibility decreases, and if it is less than the lower limit of the above range, gas is generated during molding, which is undesirable.

Here, the number average molecular weight (Mn) of polyalkylene glycol (B) is a number average molecular weight measured based on JIS K1577 and calculated based on the terminal hydroxyl value.

As polyalkylene glycol (B), various polyalkylene glycols can be used, for example, branched polyalkylene glycol represented by the following general formula (1) or linear polyalkylene glycol represented by the following general formula (2) Alkylene glycol is a preferred example. In addition, the branched polyalkylene glycol represented by the following general formula (1) or the linear polyalkylene glycol represented by the following general formula (2) may be a copolymer with other copolymerization components, but is preferably a homopolymer. .

[Formula 1]

(Wherein, R represents an alkyl group having 1 to 3 carbon atoms, and or an aralkyl group having 7 to 23 carbon atoms, and m represents an integer of 10 to 400)

The branched polyalkylene glycol represented by the general formula (1) may be a homopolymer composed of one type of R, or may be a copolymer composed of different R.

[Formula 2]

(Wherein, p represents an integer from 2 to 6, r represents an integer from 6 to 100)

The linear polyalkylene glycol represented by the general formula (2) may be a homopolymer composed of one type of p, or may be a copolymer composed of different p.

As the branched polyalkylene glycol, in the general formula (1), (2-methyl)ethylene glycol wherein

Examples of straight-chain polyalkylene glycol include polyethylene glycol in the general formula (2), where Preferred examples include polypentamethylene glycol with a p value of 5 and polyhexamethylene glycol with a p value of 6, and more preferably polytrimethylene glycol and polytetramethylene glycol.

The polyalkylene glycol (B) is a branched alkylene selected from the linear alkylene ether unit (P1) represented by the general formula (3) below and the units represented by the general formulas (4-1) to (4-4) below. Polyalkylene glycol copolymers having ether units (P2) are also mentioned as preferred ones.

[Formula 3]

(In formula (3), p represents an integer of 2 to 6)

The linear alkylene ether unit represented by general formula (3) may be a single unit made of one type of p, or may be a mixture of a plurality of units made of different p.

[Formula 4]

(In formulas (4-1) to (4-4), R ¹ to R ¹⁰ each independently represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and each of formulas (4-1) to (4-4) In this case, at least one of R ¹ to R ¹⁰ is an alkyl group having 1 to 3 carbon atoms)

The branched alkylene ether units represented by general formulas (4-1) to (4-4) include branched alkylene ether units having any of the structures represented by general formulas (4-1) to (4-4). It may be a homopolymer, or it may be a copolymer composed of branched alkylene ether units of a plurality of structures.

The linear alkylene ether unit (P1) represented by the above general formula (3), when described as glycol, is ethylene glycol with p of 2, trimethylene glycol with p of 3, tetramethylene glycol with p of 4, and p of Examples include pentamethylene glycol with a p of 5 and hexamethylene glycol with a p of 6. These may be mixed, and trimethylene glycol and tetramethylene glycol are preferred, and tetramethylene glycol is particularly preferred.

Trimethylene glycol is industrially obtained by hydroformylating ethylene oxide to obtain 3-hydroxypropionaldehyde and hydrogenating it, or by hydrogenating 3-hydroxypropionaldehyde obtained by hydrating acrolein with a Ni catalyst. It is manufactured using a method such as In addition, in recent years, trimethylene glycol has been produced by reducing glycerin, glucose, starch, etc. with microorganisms using biomethods.

As a branched alkylene ether unit represented by the above general formula (4-1), when described as glycol, (2-methyl)ethylene glycol, (2-ethyl)ethylene glycol, (2,2-dimethyl)ethylene glycol, etc. These may be mixed, and preferably (2-methyl)ethylene glycol and (2-ethyl)ethylene glycol.

As a branched alkylene ether unit represented by the general formula (4-2), when described as glycol, (2-methyl)trimethylene glycol, (3-methyl)trimethylene glycol, (2-ethyl)trimethylene glycol, (3-ethyl)triethylene glycol, (2,2-dimethyl)trimethylene glycol, (2,2-methylethyl)trimethylene glycol, (2,2-diethyl)trimethylene glycol (i.e. neopentyl glycol) , (3,3-dimethyl)trimethylene glycol, (3,3-methylethyl)trimethylene glycol, (3,3-diethyl)trimethylene glycol, etc., and these may be mixed.

As a branched alkylene ether unit represented by the general formula (4-3), when described as glycol, (3-methyl)tetramethylene glycol, (4-methyl)tetramethylene glycol, (3-ethyl)tetramethylene glycol, (4-ethyl)tetramethylene glycol, (3,3-dimethyl)tetramethylene glycol, (3,3-methylethyl)tetramethylene glycol, (3,3-diethyl)tetramethylene glycol, (4,4-dimethyl )Tetramethylene glycol, (4,4-methylethyl)tetramethylene glycol, (4,4-diethyl)tetramethylene glycol, etc. may be mixed, and (3-methyl)tetramethylene glycol desirable.

As a branched alkylene ether unit represented by the general formula (4-4), when described as glycol, (3-methyl)pentamethylene glycol, (4-methyl)pentamethylene glycol, (5-methyl)pentamethylene glycol, (3-ethyl)pentamethylene glycol, (4-ethyl)pentamethylene glycol, (5-ethyl)pentamethylene glycol, (3,3-dimethyl)pentamethylene glycol, (3,3-methylethyl)pentamethylene glycol, (3,3-diethyl)pentamethylene glycol, (4,4-dimethyl)pentamethylene glycol, (4,4-methylethyl)pentamethylene glycol, (4,4-diethyl)pentamethylene glycol, (5, Examples include 5-dimethyl)pentamethylene glycol, (5,5-methylethyl)pentamethylene glycol, and (5,5-diethyl)pentamethylene glycol, and these may be mixed.

Above, the units represented by the general formulas (4-1) to (4-4) constituting the branched alkylene ether unit have been described using glycol as an example for convenience. However, it is not limited to these glycols, and these alkylene oxides and , or polyether-forming derivatives thereof may be used.

As a preferred polyalkylene glycol copolymer, a copolymer composed of a tetramethylene ether unit and a unit represented by the general formula (4-3) is preferable, and particularly a copolymer composed of a tetramethylene ether unit and a 3-methyltetramethylene ether unit. Copolymers are more preferred. Also, copolymers consisting of a tetramethylene ether unit and a unit represented by the general formula (4-1) are also preferred, especially copolymers consisting of a tetramethylene ether unit and a 2-methylethylene ether unit, and a copolymer consisting of a tetramethylene ether unit and a unit represented by the general formula (4-1) -A copolymer composed of ethylethylene ether units is more preferable. Furthermore, a copolymer composed of tetramethylene ether units and the general formula (4-2) is also preferable, and a copolymer composed of 2,2-dimethyltrimethylene ether units, that is, neopentyl glycol ether units, is also preferable.

The polyalkylene glycol copolymer may be a random copolymer or a block copolymer.

The linear alkylene ether unit (P1) represented by the general formula (3) and the branched alkylene ether unit (P2) represented by the general formulas (4-1) to (4-4) of the polyalkylene glycol copolymer. The copolymerization ratio is the molar ratio of (P1)/(P2), and is preferably 95/5 to 5/95, more preferably 93/7 to 40/60, and even more preferably 90/10 to 65/ 35, and it is more preferable that the linear alkylene ether unit (P1) is rich.

In addition, the mole fraction is measured using a ¹ H-NMR measuring device using deuterated chloroform as a solvent.

In addition, as polyalkylene glycol (B), even if one or both ends of the polyalkylene glycol (B) are blocked with a fatty acid or alcohol, its performance is not affected, and fatty acid esters or ethers can be used equally. Therefore, the general formula X and/or Y in (1) and (2) may be an aliphatic acyl group or an alkyl group having 1 to 23 carbon atoms.

The esterified or etherified product of polyalkylene glycol does not necessarily need to be entirely esterified or etherified, and is preferably a partially esterified or etherified product.

As the fatty acid esterified product, either linear or branched fatty acid ester can be used, and the fatty acid constituting the fatty acid ester may be a saturated fatty acid or an unsaturated fatty acid. Additionally, those in which some of the hydrogen atoms are replaced with substituents such as hydroxyl groups can also be used.

Fatty acids constituting fatty acid esters include monovalent or divalent fatty acids having 1 to 23 carbon atoms, such as monovalent saturated fatty acids, specifically formic acid, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, and enanthic acid. , caprylic acid, capric acid, lauric acid, myristic acid, pentadecylic acid, palmitic acid, heptadecylic acid, stearic acid, nonadecanoic acid, arachidic acid, behenic acid, monovalent unsaturated fatty acids, specifically Examples include unsaturated fatty acids such as oleic acid, elaidic acid, linoleic acid, linolenic acid, and arachidonic acid, and divalent fatty acids having 10 or more carbon atoms, specifically sebacic acid, undecanedioic acid, dodecanedioic acid, tetradecanedioic acid, and tapps acid. and decene diic acid, undecene diic acid, and dodecene diic acid.

These fatty acids can be used one type or in combination of two or more types. The fatty acids also include fatty acids having one or more hydroxyl groups in the molecule.

Preferred specific examples of the fatty acid ester of polyalkylene glycol include polypropylene glycol stearate, where in the general formula (I-1), R is a methyl group, Examples include polypropylene glycol behenate, where Y is an aliphatic acyl group having 22 carbon atoms. Preferred specific examples of fatty acid esters of polyalkylene glycol include polyalkylene glycol monopalmitic acid ester, polyalkylene glycol dipalmitic acid ester, polyalkylene glycol monostearic acid ester, and polyalkylene glycol distearic acid ester. , polyalkylene glycol (monopalmitic acid, monostearic acid) ester, polyalkylene glycol behenate, etc.

The alkyl group constituting the alkyl ether of polyalkylene glycol may be linear or branched, for example, methyl group, ethyl group, propyl group, butyl group, octyl group, lauryl group, stearyl group, etc. and an alkyl group having 1 to 23 carbon atoms. Preferred examples of such polyalkylene glycol include alkyl methyl ether, ethyl ether, butyl ether, lauryl ether, and stearyl ether of polyalkylene glycol. there is.

The polyalkylene glycol (B) may contain a structure derived from polyols such as 1,4-butanediol, glycerol, sorbitol, benzenediol, bisphenol A, cyclohexanediol, and spiroglycol. By adding these polyols during polymerization of polyalkylene glycol, these organic groups can be added to the main chain. Particularly preferred examples include glycerol, sorbitol, and bisphenol A.

Polyalkylene glycols containing an organic group in the structure include, for example, polyethylene glycol glyceryl ether, poly(2-methyl)ethylene glycol glyceryl ether, poly(2-ethyl)ethylene glycol glyceryl ether, and polytetramethylene. Glycol glyceryl ether, polyethylene glycol-poly(2-methyl)ethylene glycol glyceryl ether, polytetramethylene glycol-poly(2-methyl)ethylene glycol glyceryl ether, polytetramethylene glycol-poly(2-ethyl)polyethylene glycol Glyceryl ether, polyethylene glycol sorbityl ether, poly(2-methyl)ethylene glycol sorbityl ether, poly(2-ethyl)ethylene glycol sorbityl ether, polytetramethylene glycol sorbityl ether, polyethylene glycol-poly(2-methyl) ) Ethylene glycol sorbityl ether, polytetramethylene glycol-poly(2-methyl)ethylene glycol sorbityl ether, polytetramethylene glycol-poly(2-ethyl)ethylene glycol sorbityl ether, bisphenol A-bis(polyethylene glycol) ether , Bisphenol A-bis(poly(2-methyl)ethylene glycol)ether, Bisphenol A-bis(poly(2-ethyl)ethylene glycol)ether, Bisphenol A-bis(polytetramethylene glycol)ether, Bisphenol A-bis( Polyethylene glycol-poly(2-methyl)ethylene glycol)ether, bisphenol A-bis(polytetramethylene glycol-poly(2-methyl)ethylene glycol)ether, bisphenol A-bis(polytetramethylene glycol-poly(2-ethyl) ) Polyethylene glycol) ether, etc. are mentioned as preferable examples.

The polyalkylene glycol (B) may be used individually or in combination of two or more types.

The content of polyalkylene glycol (B) is 0.1 to 4 parts by mass with respect to 100 parts by mass of polycarbonate resin (A). The preferred content is 0.15 parts by mass or more, more preferably 0.2 parts by mass or more, preferably 3.5 parts by mass or less, more preferably 3 parts by mass or less, further preferably 2.5 parts by mass or less, especially preferably 2 parts by mass. It is below wealth. If the content is less than 0.1 parts by mass, the improvement in color or yellowing is not sufficient, and if it exceeds 4 parts by mass, the transmittance decreases due to clouding of the polycarbonate resin, and strand breaks occur frequently during melt kneading using an extruder. And, the production of resin composition pellets becomes difficult.

[Trip Stabilizer (C)]

The polycarbonate resin composition of the present invention contains a phosphorus-based stabilizer. By containing a phosphorus-based stabilizer, the polycarbonate resin composition of the present invention has a good color and further improves heat discoloration resistance.

As a phosphorus-based stabilizer, any known stabilizer can be used. Specific examples include oxoacids of phosphorus such as phosphoric acid, phosphonic acid, phosphorous acid, phosphinic acid, and polyphosphoric acid; Acidic metal salts of pyrophosphate such as sodium acid pyrophosphate, potassium acid pyrophosphate, and calcium acid pyrophosphate; Phosphates of Group 1 or Group 2B metals such as potassium phosphate, sodium phosphate, cesium phosphate, and zinc phosphate; Phosphate compounds, phosphite compounds, phosphonite compounds, etc. may be mentioned, and phosphite compounds are particularly preferable. By selecting a phosphite compound, a polycarbonate resin composition with higher discoloration resistance and continuous productivity is obtained.

Here, the phosphite compound is a trivalent phosphorus compound represented by the general formula: P(OR) ₃ , and R represents a monovalent or divalent organic group.

Such phosphite compounds include, for example, triphenyl phosphite, tris (monononylphenyl) phosphite, tris (monononyl/dinonyl·phenyl) phosphite, and tris (2,4-di-tert-butyl). Phenyl) phosphite, monooctyl diphenyl phosphite, dioctyl monophenyl phosphite, monodecyl diphenyl phosphite, didecyl monophenyl phosphite, tridecyl phosphite, trilauryl phosphite, tristearyl phosphite, Distearyl pentaerythritol diphosphite, bis(2,4-di-tert-butyl-4-methylphenyl)pentaerythritol phosphite, bis(2,6-di-tert-butylphenyl)octyl phosphite, 2, 2-methylenebis(4,6-di-tert-butylphenyl)octylphosphite, tetrakis(2,4-di-tert-butylphenyl)-4,4'-biphenylene-diphosphite, 6-[ 3-(3-tert-butyl-hydroxy-5-methylphenyl)propoxy]-2,4,8,10-tetra-tert-butyldibenzo[d,f][1,3,2]-dioxa Phospepine, etc. can be mentioned.

Among such phosphite compounds, an aromatic phosphite compound represented by the following formula (1) or (2) is more preferable because it effectively increases the heat discoloration resistance of the polycarbonate resin composition of the present invention.

[Formula 5]

[In formula (1), R ¹ , R ² and R ³ may each be the same or different and represent an aryl group having 6 to 30 carbon atoms.]

[Formula 6]

[In formula (2), R ⁴ and R ⁵ may be the same or different, and represent an aryl group having 6 to 30 carbon atoms.]

As the phosphite compound represented by the above formula (1), triphenyl phosphite, tris (monononylphenyl) phosphite, tris (2,4-di-tert-butylphenyl) phosphite, etc. are preferable, and Among them, tris(2,4-di-tert-butylphenyl)phosphite is more preferable. Specifically, such organic phosphite compounds include, for example, “Adekastab 1178” manufactured by ADEKA, “Sumiriza TNP” manufactured by Sumitomo Chemical Company, “JP-351” manufactured by Johoku Chemical Industries, Ltd., and ADEKA Corporation. “Adekastabe 2112,” “Irgaphos 168,” manufactured by BASF, and “JP-650,” manufactured by Johoku Chemical Industries, Ltd., etc.

Phosphite compounds represented by the formula (2) include, among others, bis(2,4-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphite and bis(2,6-di-tert-butyl-4). Those having a pentaerythritol diphosphite structure such as -methylphenyl)pentaerythritol diphosphite and bis(2,4-dicumylphenyl)pentaerythritol diphosphite are particularly preferred. As such organic phosphite compounds, for example, "Adekastab PEP-24G" and "Adekastab PEP-36" manufactured by Adeka, and "Doverphos S-9228" manufactured by Doverchemical, etc. are preferred. It can be heard.

Among the phosphite compounds, the aromatic phosphite compound represented by the above formula (2) is more preferable because it has a better color.

In addition, one type of phosphorus-based stabilizer may be contained, or two or more types may be contained in any combination and ratio.

The content of the phosphorus stabilizer (C) is 0.005 to 0.5 parts by mass, preferably 0.007 parts by mass or more, more preferably 0.008 parts by mass or more, particularly preferably 0.01 parts by mass, based on 100 parts by mass of the polycarbonate resin (A). It is at least 0.4 parts by mass, and is preferably at most 0.4 parts by mass, more preferably at most 0.3 parts by mass, even more preferably at most 0.2 parts by mass, and especially at most 0.1 parts by mass. If the content of the phosphorus-based stabilizer (C) is less than 0.005 parts by mass of the above range, the color and heat discoloration resistance will become insufficient, and if the content of the phosphorus-based stabilizer (C) exceeds 0.5 parts by mass, the heat discoloration resistance will actually worsen. In addition, moist heat stability is also reduced.

[Epoxy compound (D)]

It is also preferable that the resin composition of the present invention contains an epoxy compound (D). By containing the epoxy compound (D) together with polyalkylene glycol (B), heat discoloration resistance can be further improved.

As the epoxy compound (D), a compound having one or more epoxy groups in one molecule is used. Specifically, phenyl glycidyl ether, allyl glycidyl ether, t-butylphenyl glycidyl ether, 3,4-epoxycyclohexylmethyl-3',4'-epoxycyclohexylcarboxylate, 3,4 -Epoxy-6-methylcyclohexylmethyl-3',4'-epoxy-6'-methylcyclohexylcarboxylate, 2,3-epoxycyclohexylmethyl-3',4'-epoxycyclohexylcarboxylate, 4-(3,4-epoxy-5-methylcyclohexyl)butyl-3',4'-epoxycyclohexylcarboxylate, 3,4-epoxycyclohexylethylene oxide, cyclohexylmethyl3,4-epoxycyclohexyl Carboxylate, 3,4-epoxy-6-methylcyclohexylmethyl-6'-methylcyclohexylcarboxylate, bisphenol-A diglycidyl ether, tetrabromobisphenol-A glycidyl ether, phthalic acid Glycidyl ester, diglycidyl ester of hexahydrophthalic acid, bis-epoxydicyclopentadienyl ether, bis-epoxyethylene glycol, bis-epoxycyclohexyl adipate, butadiene diepoxide, tetraphenylethylene epoxide, Octyl epoxytalate, epoxidized polybutadiene, 3,4-dimethyl-1,2-epoxycyclohexane, 3,5-dimethyl-1,2-epoxycyclohexane, 3-methyl-5-t-butyl-1, 2-Epoxycyclohexane, octadecyl-2,2-dimethyl-3,4-epoxycyclohexylcarboxylate, N-butyl-2,2-dimethyl-3,4-epoxycyclohexylcarboxylate, cyclohexyl- 2-methyl-3,4-epoxycyclohexylcarboxylate, N-butyl-2-isopropyl-3,4-epoxy-5-methylcyclohexylcarboxylate, octadecyl-3,4-epoxycyclohexylcarboxylate Boxylate, 2-ethylhexyl-3',4'-epoxycyclohexylcarboxylate, 4,6-dimethyl-2,3-epoxycyclohexyl-3',4'-epoxycyclohexylcarboxylate, 4, 5-Epoxy tetrahydrophthalic anhydride, 3-t-butyl-4,5-epoxy tetrahydrophthalic anhydride, diethyl 4,5-epoxy-cis-1,2-cyclohexyldicarboxylate, di-n-butyl Preferred examples include -3-t-butyl-4,5-epoxy-cis-1,2-cyclohexyldicarboxylate, epoxidized soybean oil, and epoxidized linseed oil.

Among these, alicyclic epoxy compounds are preferably used, and 3,4-epoxycyclohexylmethyl-3',4'-epoxycyclohexylcarboxylate is particularly preferable.

Additionally, polyalkylene glycol derivatives having an epoxy group at one or both ends can also be preferably used. In particular, polyalkylene glycol having epoxy groups at both ends is preferred.

Polyalkylene glycol derivatives containing an epoxy group in the structure include, for example, polyethylene glycol diglycidyl ether, poly(2-methyl)ethylene glycol diglycidyl ether, and poly(2-ethyl)ethylene glycol digly. Sidyl ether, polytetramethylene glycol diglycidyl ether, polyethylene glycol-poly(2-methyl)ethylene glycol diglycidyl ether, polytetramethylene glycol-poly(2-methyl)ethylene glycol diglycidyl ether, Preferred examples include polyalkylene glycol derivatives such as polytetramethylene glycol-poly(2-ethyl)ethylene glycol diglycidyl ether.

Epoxy compounds may be used individually or in combination of two or more types.

The preferred content of the epoxy compound (D) is 0.0005 to 0.2 parts by mass, more preferably 0.001 parts by mass or more, further preferably 0.003 parts by mass or more, particularly preferably, based on 100 parts by mass of the polycarbonate resin (A). is 0.005 parts by mass or more, more preferably 0.15 parts by mass or less, further preferably 0.1 parts by mass or less, particularly preferably 0.05 parts by mass or less. If the content of the epoxy compound (D) is less than 0.0005 parts by mass, the color and heat discoloration resistance tend to become insufficient, and if it exceeds 0.2 parts by mass, the heat discoloration resistance tends to worsen, and the color and wet heat stability also deteriorate. easy to become

[Additives, etc.]

The polycarbonate resin composition of the present invention contains other additives than those described above, such as antioxidants, mold release agents, ultraviolet absorbers, fluorescent whitening agents, pigments, dyes, polymers other than polycarbonate resin, flame retardants, impact resistance improvers, It may contain additives such as antistatic agents, plasticizers, and compatibilizers. You may mix these additives one type or two or more types.

However, when containing a polymer other than the polycarbonate resin, the content is preferably 20 parts by mass or less, more preferably 10 parts by mass or less, with respect to 100 parts by mass of the polycarbonate resin (A), and further. It is preferably 5 parts by mass or less, especially 3 parts by mass or less.

[Method for producing polycarbonate resin composition]

There is no limitation to the method for producing the polycarbonate resin composition of the present invention, and widely known methods for producing polycarbonate resin compositions can be adopted, including polycarbonate resin (A), polyalkylene glycol (B), and phosphorus stabilizer (C). ), and other components mixed as necessary are premixed using various mixers such as a tumbler or Henschel mixer, and then mixed with a Banbury mixer, roll, Brabender, single-screw kneading extruder, or twin-screw kneading extruder, A method of melt-kneading with a mixer such as a kneader is included. In addition, the temperature of melt kneading is not particularly limited, but is usually in the range of 240 to 320°C.

[Optical components]

The polycarbonate resin composition for optical components of the present invention can be used to manufacture optical components by molding pellets obtained by pelletizing the polycarbonate resin composition described above using various molding methods. In addition, the resin melted and kneaded using an extruder can be directly molded into optical components without going through pellets.

The polycarbonate resin composition of the present invention has excellent fluidity and color, and generates very little gas and mold contamination during molding. Therefore, optical components, especially thin optical components that are prone to mold contamination, are molded by injection molding. It is particularly preferably used for: The resin temperature during injection molding is preferably higher than the resin temperature of 260 to 300°C, which is the temperature generally applied to injection molding of polycarbonate resin, especially in the case of thin molded articles, and the resin temperature is 305 to 400°C. temperature is preferred. The resin temperature is more preferably 310°C or higher, more preferably 315°C or higher, particularly preferably 320°C or higher, and more preferably 390°C or lower. When using a conventional polycarbonate resin composition, there was a problem that yellowing of the molded product was likely to occur if the resin temperature during molding was increased to mold a thin molded product. However, by using the resin composition of the present invention, the above temperature Even within this range, it becomes possible to manufacture molded products with good color, especially thin optical components.

In addition, the resin temperature is understood as the barrel set temperature when it is difficult to measure it directly.

Here, a thin molded product refers to a molded product having a plate-like portion whose thickness is usually 1 mm or less, preferably 0.8 mm or less, and more preferably 0.6 mm or less. Here, the plate-shaped portion may be flat or curved, may have a flat surface, may have irregularities, etc. on the surface, and the cross section may have an inclined surface or a wedge-shaped cross section.

Optical components include parts of devices and instruments that directly or indirectly use light sources such as LEDs, organic ELs, incandescent bulbs, fluorescent lamps, and cathode tubes, and representative examples include light guide plates and members for surface light emitters.

The light guide plate is used to guide light from a light source such as LED among liquid crystal backlight units, various display devices, and lighting devices. The light incident from the side or back side is usually diffused by irregularities formed on the surface to distribute it uniformly. generates light. The shape is usually flat, and the surface may or may not have irregularities.

The light guide plate is usually molded, preferably by injection molding, ultra-high-speed injection molding, injection compression molding, or melt extrusion molding (for example, T-die molding).

The light guide plate molded using the resin composition of the present invention has no cloudiness or decrease in transmittance, has good color, and has few molding defects due to mold contamination.

A light guide plate using the polycarbonate resin composition of the present invention can be suitably used in the fields of liquid crystal backlight units, various display devices, and lighting devices. Examples of such devices include various portable terminals such as mobile phones, mobile notes, netbooks, slate PCs, tablet PCs, smart phones, tablet-type terminals, cameras, watches, note PCs, various displays, lighting devices, etc. .

Moreover, the shape of the optical component may be a film or a sheet, and specific examples thereof include a light guide film.

In addition, as optical components, light guides and lenses that guide light from a light source such as LED in headlights (headlamps), rear lamps, fog lamps, etc. for vehicles such as automobiles or motorcycles are also preferable, and can be preferably used for these as well. You can.

A light guide plate using the polycarbonate resin composition of the present invention can be suitably used in the fields of liquid crystal backlight units, various display devices, and lighting devices. Examples of such devices include various portable terminals such as mobile phones, mobile notes, netbooks, slate PCs, tablet PCs, smart phones, tablet-type terminals, cameras, watches, note PCs, various displays, lighting devices, etc. .

Example

Hereinafter, the present invention will be described in more detail by referring to examples. However, the present invention is not to be construed as limited to the following examples.

The raw materials and evaluation methods used in the following examples and comparative examples are as follows. In addition, the method for measuring the viscosity average molecular weight of the polycarbonate resin (A) is as described above.

Measurement of the weight average molecular weight (Mw) of polyalkylene glycol by gel permeation chromatography was specifically performed as follows.

HLC-8320 (manufactured by Tosoh Corporation) was used as a gel permeation chromatography apparatus, and TSKgel MultiporeHxl-M (7.8 mm I.D. × 30 cmL × 2, manufactured by Tosoh Corporation) was used as a column. The column temperature was 40°C. The detector used was the RI detector of HLC-8320. As an eluent, tetrahydrofuran was used, and a calibration curve was prepared using standard polystyrene (manufactured by Tosoh Corporation).

The ratio (mass %) of the component with Mw of 400 or less was calculated by dividing the area of the portion with Mw of 400 or less in the GPC spectrum curve obtained above by the area of the entire spectrum curve.

In addition, the water-washed products of polyalkylene glycol (B1) and (B3) were obtained by the following water-washing treatment.

That is, 100 g of the raw material polyalkylene glycol described above was added to 500 ml of pure water at a temperature of 40 to 50°C and stirred for 5 minutes, then the stirring was stopped and left still to separate into a polyalkylene glycol layer and an aqueous layer, The polyalkylene glycol layer was separated. This operation was repeated twice, and the obtained polyalkylene glycol was heated at 120°C for 10 hours to remove moisture, and polyalkylene glycol (B1) and (B3) were obtained.

(Examples 1 to 10, Comparative Examples 1 to 3)

[Manufacture of resin composition pellets]

Each of the above components was mixed in the proportions (parts by mass) shown in Table 2 below, mixed with a tumbler for 20 minutes, and then extruded into a single-screw extruder (“VS-40” manufactured by Tanabe Plastic Machinery Co., Ltd.) equipped with a vent with a screw diameter of 40 mm. "), the cylinder temperature was melt-kneaded at 240°C, and pellets were obtained by strand cutting.

[Measurement of color (YI)]

The obtained pellets were dried at 120°C for 5 to 7 hours using a hot air circulation type dryer, and then subjected to a long furnace ( A long-light molded product (300 mm × 7 mm × 4 mm) was molded.

For this long optical path molded product, YI (yellowing degree) was measured at an optical path length of 300 mm. For the measurement, a long-wavelength spectral transmission colorimeter (“ASA 1” manufactured by Nippon Sensei Industries, C light source, 2° field of view) was used.

[Evaluation of mold contamination (mold attachment)]

Contamination evaluation in injection molding (mold contamination)

After drying the pellets obtained above at 120°C for 5 hours, the cylinder temperature was set to 340°C using an injection molding machine (“SE8M” manufactured by Sumitomo Heavy Industries, Ltd.) and a drop-type mold as shown in Fig. 1. Under the conditions of a molding cycle of 10 seconds and a mold temperature of 40°C, 200 shot injection molding was performed, and the state of contamination due to white deposits generated on the metal mirror surface on the mold fixing side after completion was visually observed based on the following standards compared with Comparative Example 1. Evaluation was made by observation.

A: The mold adhesion was much less than the state after 200 shot molding in Comparative Example 1, and the mold contamination resistance was very good.

B: Mold adhesion was less than the state after 200 shot molding in Comparative Example 1, but mold contamination resistance was slightly observed.

C: Mold attachment is at the same level as the state after 200 shot molding in Comparative Example 1.

D: The amount of mold adhesion was greater than the state after 200 shot molding in Comparative Example 1, and mold contamination was significantly observed.

In addition, the drop-shaped mold in FIG. 1 is a mold designed so that the resin composition is introduced from the gate (G) and the generated gas can easily collect at the tip (P). The width of the gate (G) is 1 mm and the thickness is 1 mm. In Figure 1, the width (h1) is 14.5 mm, the length (h2) is 7 mm, and the length (h3) is 27 mm, and the thickness of the molded portion is It is 3 mm.

The above evaluation results are shown in Table 2 below.

The polycarbonate resin composition of the present invention has good color and generates very little gas and mold contamination during molding, so it can be very suitably used in optical components.

Claims (5)

Containing 0.8 to 1.10 parts by mass of polyalkylene glycol (B) and 0.005 to 0.5 parts by mass of phosphorus-based stabilizer (C), based on 100 parts by mass of polycarbonate resin (A),
Polyalkylene glycol (B) contains less than 1.0% by mass of a component with a molecular weight of 400 or less, as measured by the following method (i) in terms of polystyrene by gel permeation chromatography using tetrahydrofuran as a solvent. The number average molecular weight (Mn) determined from the terminal hydroxyl value by method (ii) is more than 1400 and 2600 or less, and is a branched polyalkylene glycol represented by the following general formula (1) or a straight chain represented by the following general formula (2) A polycarbonate resin composition for optical components, characterized in that it is a homopolymer of type polyalkylene glycol.

(In formula (1), R represents an alkyl group having 1 to 3 carbon atoms, and represents an aryl group or an aralkyl group having 7 to 23 carbon atoms, and m represents an integer of 10 to 400.)

(In formula (2), , p represents an integer from 2 to 6, and r represents an integer from 6 to 100)
Method (i): The ratio (mass %) of the component with a molecular weight of 400 or less is calculated by dividing the area of the portion with a molecular weight of 400 or less in the obtained GPC spectrum curve by the area of the entire spectrum curve.
Method (ii): Mn is measured based on JIS K1577 and calculated based on the terminal hydroxyl value. According to claim 1,
A polycarbonate resin composition for optical components, wherein the polyalkylene glycol (B) has a tetramethylene ether unit. According to claim 2,
A polycarbonate resin composition for optical components, characterized in that the molar ratio of the tetramethylene ether unit of polyalkylene glycol (B) is 50 mol% or more. According to claim 1,
Additionally, a polycarbonate resin composition for optical components containing 0.0005 to 0.2 parts by mass of an epoxy compound (D) based on 100 parts by mass of the polycarbonate resin (A). An optical component molded from the polycarbonate resin composition according to any one of claims 1 to 4.

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