JP6912639B2 - Polycarbonate resin composition for optical components - Google Patents

Description

The present invention relates to a polycarbonate resin composition for optical parts, and more particularly to a polycarbonate resin composition for optical parts, which has a good hue and has an improved problem of cracking during molding.

Liquid crystal display devices used in personal computers, mobile phones, and the like incorporate a planar light source device in order to meet the demands for thinning, weight reduction, labor saving, and high definition. The planar light source device is provided with a light guide plate having a flat plate shape or the like for the purpose of uniformly and efficiently guiding the incoming light to the liquid crystal display side.

Such a light guide plate is obtained by injection molding of a thermoplastic resin. Conventionally, the light guide plate has been molded from a resin material such as polymethyl methacrylate (PMMA), but recently, there is a demand for a display device that displays a clearer image, and the heat generated in the vicinity of the light source raises the temperature inside the device. Therefore, it is being replaced with a polycarbonate resin material having higher heat resistance.

Polycarbonate resin is excellent in mechanical properties, thermal properties, electrical properties, and weather resistance, but its light transmittance is lower than that of PMMA, etc. When configured, there is a problem that the brightness is low. Recently, it has been required to reduce the difference in chromaticity between the light input portion of the light guide plate and the place away from the light input portion, but there is a problem that the polycarbonate resin is more likely to turn yellow than the PMMA resin.

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

However, in the method of Patent Document 1, although the hue is improved by adding the acrylic resin, the light transmittance and the brightness cannot be increased because it becomes cloudy, and the transmittance is improved by adding the alicyclic epoxy. However, no effect of improving hue is observed. In the case of Patent Document 2 and Patent Document 3, although the effect of improving fluidity and transferability can be expected, there is a drawback that the heat resistance is lowered.

On the other hand, it is known in Patent Document 4 and Patent Document 5 that polyethylene glycol, poly (2-methyl) ethylene glycol and the like are blended with a thermoplastic resin such as a polycarbonate resin. Then, the applicant in Patent Document 6 describes the formula: X-О- [CH (-R) -CH _2- O] _n- Y (in the formula, R is a hydrogen atom or an alkyl having 1 to 3 carbon atoms. We have proposed to improve the transmittance and hue by blending polyethylene glycol or poly (2-alkyl) ethylene glycol represented by (group).

However, especially recently, in various mobile terminals such as smartphones and tablet terminals, thinning and large-sized thinning are progressing at a remarkable speed, and the required specifications are increasing for such high-end light guide plates. It is becoming more sophisticated.

Japanese Unexamined Patent Publication No. 11-158364 Japanese Unexamined Patent Publication No. 2001-208917 Japanese Unexamined Patent Publication No. 2001-215336 Japanese Unexamined Patent Publication No. 1-22959 Japanese Unexamined Patent Publication No. 9-227785 Japanese Patent No. 4069364

However, the polycarbonate resin composition containing the polyalkylene glycol as described above needs to raise the molding temperature at the time of injection molding, especially when molding a thin-walled molded product such as a light guide plate for high-end products, and as a result. The present inventor has found that there is a problem that the molded product is easily cracked.
An object (object) of the present invention is to provide a polycarbonate resin composition for an optical component, which has a good hue and has an improved problem of cracking during molding.

As a result of diligent studies to achieve the above problems, the present inventor has found that the occurrence rate of the above-mentioned molding cracks changes depending on the pH value of the polyalkylene glycol, and the polyalkylene glycol which is acidic as the polyalkylene glycol. The present invention has been completed by finding that a polycarbonate resin composition containing a specific amount of a phosphorus-based stabilizer has an excellent hue and the occurrence of cracks during molding is remarkably reduced.
The present invention relates to the following polycarbonate resin compositions for optical components.

[1] With respect to 100 parts by mass of the polycarbonate resin (A), 0.1 to 4 parts by mass of polyalkylene glycol (B) having a pH of less than 7.0 measured in accordance with JIS K1557-5 and phosphorus-based A polycarbonate resin composition for optical parts, which comprises 0.005 to 0.5 parts by mass of a stabilizer (C).
[2] The polycarbonate resin composition for optical components according to the above [1], wherein the pH of the polyalkylene glycol (B) is in the range of 3.0 or more and less than 7.0.
[3] The polycarbonate resin composition for optical components according to the above [1] or [2], wherein the polyalkylene glycol (B) is a polyalkylene glycol having a propylene glycol unit.
[4] The polycarbonate resin composition for optical components according to the above [1] or [2], wherein the polyalkylene glycol (B) is a polyalkylene glycol having a tetramethylene glycol unit.
[5] The above [1], wherein the polyalkylene glycol (B) adjusted with hydrochloric acid or phosphoric acid so that the pH is in the range of 3.0 or more and less than 7.0 is blended with the polycarbonate resin (A). ] To [4]. The method for producing a polycarbonate resin composition for an optical component.
[6] The polycarbonate resin composition for optical components according to the above [5], wherein the polyalkylene glycol having a pH of 7.0 or more is used and the polyalkylene glycol (B) having a pH adjusted to a pH of 3.0 or more and less than 7.0 is used. Manufacturing method of things.

The polycarbonate resin composition for optical components of the present invention has a good hue, the problem of cracking during molding is improved, and has excellent fluidity and high light transmittance.

Hereinafter, the present invention will be described in detail with reference to embodiments and examples.
In addition, in this specification, "~" is used in the meaning which includes the numerical values described before and after it as the lower limit value and the upper limit value unless otherwise specified.

The polycarbonate resin composition for optical components of the present invention contains 0 polyalkylene glycol (B) having a pH of less than 7.0 measured in accordance with JIS K1557-5 with respect to 100 parts by mass of the polycarbonate resin (A). It is characterized by containing 1 to 4 parts by mass and 0.005 to 0.5 parts by mass of the phosphorus-based stabilizer (C).
Hereinafter, each component and the like constituting the polycarbonate resin composition for optical components of the present invention will be described in detail.

[Polycarbonate resin (A)]
The polycarbonate resin is a polymer having a basic structure having a carbonic acid bond represented by the formula:-[-O-X-OC (= O)-]-. In the formula, X is generally a hydrocarbon, but X having a heteroatom or a heterobond introduced may be used to impart various properties.

Further, the polycarbonate resin can be classified into an aromatic polycarbonate resin in which the carbon directly bonded to the carbonic acid bond is an aromatic carbon and an aliphatic polycarbonate resin in which an aliphatic carbon is used, and any of them can be used. Of these, aromatic polycarbonate resins are preferable from the viewpoints of heat resistance, mechanical properties, electrical properties, and the like.

The specific type of the polycarbonate resin is not limited, and examples thereof include a polycarbonate polymer obtained by reacting a dihydroxy compound with a carbonate precursor. At this time, in addition to the dihydroxy compound and the carbonate precursor, a polyhydroxy compound or the like may be reacted. Alternatively, a method of reacting carbon dioxide with cyclic ether using carbon dioxide as a carbonate precursor may also be used. Further, the polycarbonate polymer may be linear or branched. Further, the polycarbonate polymer may be a copolymer composed of one type of repeating unit or a copolymer having two or more types of repeating units. At this time, as the copolymer, various copolymer forms such as a random copolymer and a block copolymer can be selected. Usually, such a polycarbonate polymer becomes a thermoplastic resin.

Among the monomers used as raw materials for aromatic polycarbonate resins, examples of aromatic dihydroxy compounds include
Dihydroxybenzenes such as 1,2-dihydroxybenzene, 1,3-dihydroxybenzene (ie resorcinol), 1,4-dihydroxybenzene;
Dihydroxybiphenyls such as 2,5-dihydroxybiphenyl, 2,2'-dihydroxybiphenyl, 4,4'-dihydroxybiphenyl;

2,2'-Dihydroxy-1,1'-binaphthyl, 1,2-dihydroxynaphthalene, 1,3-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, 1 , 7-Dihydroxynaphthalene, 2,7-dihydroxynaphthalene and other dihydroxynaphthalene;

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

2,2-bis (4-hydroxyphenyl) propane (ie, 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'-Dihydroxydiphenylsulfide,
Dihydroxydiarylsulfides such as 4,4'-dihydroxy-3,3'-dimethyldiphenylsulfide;

Dihydroxydiarylsulfoxides such as 4,4'-dihydroxydiphenylsulfoxide, 4,4'-dihydroxy-3,3'-dimethyldiphenylsulfoxide;

4,4'-Dihydroxydiphenyl sulfone,
Dihydroxydiaryl sulfones such as 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfone;
And so on.

Among these, bis (hydroxyaryl) alkanes are preferable, and bis (4-hydroxyphenyl) alkanes are particularly preferable, and 2,2-bis (4-hydroxyphenyl) propane (particularly from the viewpoint of impact resistance and heat resistance). That is, bisphenol A) is preferable.
As the aromatic dihydroxy compound, one type may be used, or two or more types may be used in any combination and ratio.

Further, to give an example of a monomer which is a raw material of an aliphatic polycarbonate resin,
Ethan-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, decane-1,10-diol;

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

Glycols such as ethylene glycol, 2,2'-oxydiethanol (ie, diethylene glycol), triethylene glycol, propylene glycol, 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'-biphenyldiethanol, 1,4- Aralkyldiols such as bis (2-hydroxyethoxy) biphenyl, bisphenol A bis (2-hydroxyethyl) ether, bisphenol S bis (2-hydroxyethyl) ether;

1,2-epoxyethane (ie, ethylene oxide), 1,2-epoxypropane (ie, propylene oxide), 1,2-epoxycyclopentane, 1,2-epoxycyclohexane, 1,4-epoxycyclohexane, 1-methyl Cyclic ethers such as -1,2-epoxycyclohexane, 2,3-epoxy norbornane, and 1,3-epoxypropane; and the like.

Among the monomers used as raw materials for the polycarbonate resin, carbonyl halides, carbonate esters and the like are used as examples of carbonate precursors. As the carbonate precursor, one kind may be used, or two or more kinds may be used in any combination and ratio.

Specific examples of the carbonyl halide include phosgene; a bischloroformate of a dihydroxy compound, a haloformate of a monochloroformate of a dihydroxy compound, and the like.

Specific examples of the carbonate ester include diaryl carbonates such as diphenyl carbonate and ditril carbonate; dialkyl carbonates such as dimethyl carbonate and diethyl carbonate; biscarbonate of dihydroxy compound, monocarbonate of dihydroxy compound, and cyclic carbonate. Examples thereof include carbonates of dihydroxy compounds such as.

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

The molecular weight of the polycarbonate resin (A) is preferably 1000 to 18000, more preferably 10500 or more, still more preferably 11000 or more, particularly preferably 11500 or more, and most preferably 12000 or more in terms of viscosity average molecular weight (Mv). Yes, more preferably 17500 or less, still more preferably 17000 or less, and particularly preferably 16500 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 present invention It is possible to suppress and improve the decrease in fluidity of the polycarbonate resin composition of the present invention, improve the molding processability, and facilitate the thin-wall molding process.
The polycarbonate resin (A) may be used by mixing two or more types of polycarbonate resins having different viscosity average molecular weights. In this case, a polycarbonate resin having a viscosity average molecular weight outside the above-mentioned suitable range is mixed. You may.

In the present invention, the viscosity average molecular weight Mv of the polycarbonate resin is determined by using methylene chloride as a solvent and determining the ultimate viscosity η (unit: dl / g) at a temperature of 20 ° C. using an Ubbelohde viscometer. It means the value calculated from the formula.
η = 1.23 × 10 ^-4 Mv ^0.83
The ultimate viscosity η is a value calculated by the following formula by measuring _{the specific viscosity η sp} at each solution concentration [C] (g / dl).

The polycarbonate resin is not limited to the embodiment containing only one type of polycarbonate resin, and is used in the sense of including, for example, a mode containing a plurality of types of polycarbonate resins having different monomer compositions and molecular weights. ), Or a combination of an alloy (mixture) of a polycarbonate resin and another thermoplastic resin may be used. Further, for example, a polycarbonate resin is used as a copolymer with an oligomer or polymer having a siloxane structure for the purpose of further improving flame retardancy and impact resistance; a phosphorus atom for the purpose of further improving thermal oxidation stability and flame retardancy. Copolymer with a monomer, oligomer or polymer having a dihydroxyanthraquinone structure; a copolymer with a monomer, oligomer or polymer having a dihydroxyanthraquinone structure for the purpose of improving thermal oxidation stability; Even if it is configured as a copolymer mainly composed of a polycarbonate resin, such as a copolymer with an oligomer or a polymer having an olefin structure; a copolymer with a polyester resin oligomer or a polymer for the purpose of improving chemical resistance; good.

Further, 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 1500 or more, preferably 2000 or more, and usually 9500 or less, preferably 9000 or less. Further, the contained polycarbonate ligomer is preferably 30% by mass or less of the polycarbonate resin (including the polycarbonate oligomer).

Further, 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 regenerated polycarbonate resin is preferably 80% by mass or less, and more preferably 50% by mass or less of the polycarbonate resin. Since the regenerated polycarbonate resin is likely to be deteriorated by heat deterioration, aging deterioration, etc., if such a polycarbonate resin is used in a larger amount than the above range, the hue and mechanical properties can be deteriorated. Because it has sexual characteristics.

[Polyalkylene glycol compound (B)]
The polycarbonate resin composition for optical components of the present invention contains polyalkylene glycol (B) having a pH of less than 7.0 as measured in accordance with JIS K1557-5 with respect to 100 parts by mass of the polycarbonate resin (A). Contains 0.1 to 4 parts by mass.

Polyalkylene glycols are usually produced in the presence of a catalyst by polymerization and copolymerization of cyclic ethers and / or diols, and the catalysts include fluorosulfonic acids, superacids such as fuming sulfuric acid, perfluorosulfonic acid resins, and zeolites. , An acid catalyst such as a heteropolyacid, or an alkaline catalyst such as lithium hydroxide, sodium hydroxide, potassium hydroxide, sodium methoxyde or the like is used. The pH value of the polyalkylene glycol immediately after production is usually, for example, about 7 to 8.

In the present invention, polyalkylene glycol (B) having a pH of less than 7.0 measured according to JIS K1557-5 is used. The pH value of commercially available polyalkylene glycols and polyalkylene oxides varies depending on the type of product, the storage condition and storage period of the product, but usually 7.0 or higher, but the pH value is 7.0. It was found that the problem of cracking during molding was greatly improved by blending less than the amount of polyalkylene glycol (B).
As described above, the pH value of commercially available polyalkylene glycol varies depending on the type of product, the storage state, and the storage period, and the pH value may change due to decomposition or deterioration depending on the storage state and period.

The polyalkylene glycol used in the present invention is a polyalkylene glycol (B) having a pH of less than 7.0 as measured according to JIS K1557-5. In the present invention, the pH value is a value measured according to the method described in 6.4.3 to 6.4.4 of JIS K1557-5 (2007).
The pH value of the polyalkylene glycol (B) is preferably 6.9 or less, more preferably 6.8 or less, still more preferably 6.7 or less, particularly 6.6 or less, and preferably 3 It is preferably 0.0 or more, more preferably 3.5 or more, still more preferably 4.0 or more, particularly 4.2 or more, particularly 4.3 or more.

The polyalkylene glycol (B) is not particularly limited as long as it has a pH value of less than 7.0, but a polyalkylene glycol having a pH of 7.0 or more is less than 7.0, preferably pH 3.0. It is preferable to use the polyalkylene glycol (B) adjusted to be less than 7.0. Further, a polyalkylene glycol having a pH adjusted to less than 7.0, preferably pH 3.0 or more and less than 7.0 may be used at the time of production, and the pH value of various commercially available polyalkylene glycols is measured. It is also preferable to control and use a pH value of less than 7.0, preferably pH 3.0 or more and less than 7.0.
Various pH adjustment methods can be used to adjust polyalkylene glycol having a pH of 7.0 or more to less than 7.0. For example, polyalkylene glycol is mixed with a solution (for example, 2-propanol and water). The pH of the polyalkylene glycol can be adjusted by dissolving it in a solution), adding a predetermined amount of hydrochloric acid to adjust the pH, reducing the pressure of the solution to remove the solvent, and further drying.

The polyalkylene glycol itself is not limited, and various polyalkylene glycols can be used. For example, a branched polyalkylene glycol represented by the following general formula (1) or a linear type represented by the following general formula (2). Polyalkylene glycols are preferred. 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 another copolymerization component. It is good, but it is preferably a copolymer.

（式中、Ｒは炭素数１〜３のアルキル基を示し、ＸおよびＹは、それぞれ独立に、水素原子、炭素数１〜２３の脂肪族アシル基、炭素数１〜２３のアルキル基、炭素数６〜２２のアリール基又は炭素数７〜２３のアラルキル基を示し、ｍは１０〜４００の整数を示す。）
上記一般式（１）で表される分岐型ポリアルキレングリコールは、一種のＲからなる単独重合体でも、また異なるＲからなる共重合体であってもよい。

(In the formula, R represents an alkyl group having 1 to 3 carbon atoms, and X and Y independently represent a hydrogen atom, an aliphatic acyl group having 1 to 23 carbon atoms, an alkyl group having 1 to 23 carbon atoms, and carbon. It represents an aryl group of number 6 to 22 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 a kind of R or a copolymer composed of a different R.

（式中、Ｘ及びＹは、それぞれ独立に、水素原子、炭素数２〜２３の脂肪族アシル基、炭素数１〜２３のアルキル基、炭素数６〜２２のアリール基又は炭素数７〜２３のアラルキル基を示し、ｐは２〜６の整数、ｒは６〜１００の整数を示す。）
上記一般式（２）で表される直鎖型ポリアルキレングリコールは、一種のｐからなる単独重合体でも、また異なるｐからなる共重合体であってもよい。

(In the formula, X and Y are independently hydrogen atoms, aliphatic acyl groups having 2 to 23 carbon atoms, alkyl groups having 1 to 23 carbon atoms, aryl groups having 6 to 22 carbon atoms, or 7 to 23 carbon atoms, respectively. Indicates an arylyl group of, p is an integer of 2 to 6, and r is an integer of 6 to 100.)
The linear polyalkylene glycol represented by the general formula (2) may be a homopolymer composed of a kind of p or a copolymer composed of different p.

As the branched polyalkylene glycol, in the general formula (1), X and Y are hydrogen atoms, and R is a methyl group (2-methyl) ethylene glycol (also known as propylene glycol) or an ethyl group (2-). Ethyl) ethylene glycol (also known as butylene glycol) is preferred.

As the linear polyalkylene glycol, X and Y in the general formula (2) are hydrogen atoms, polyethylene glycol having p of 2, polytrimethylethylene glycol having p of 3, and polytetramethylene having p of 4. Glycol, polypentamethylene glycol having p of 5 and polyhexamethylene glycol having p of 6 are preferable, and polytrimethylene glycol and polytetramethylene glycol are more preferable.

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

（式（３）中、ｐは２〜６の整数を示す。）
一般式（３）で表される直鎖アルキレンエーテル単位としては、一種のｐからなる単独の単位でも、また異なるｐからなる複数の単位が混合していてもよい。

(In equation (3), p represents an integer of 2 to 6.)
The linear alkylene ether unit represented by the general formula (3) may be a single unit composed of a kind of p, or a plurality of units composed of different ps may be mixed.

（式（４−１）〜（４−４）中、Ｒ^１〜Ｒ^１０は各々独立に水素原子又は炭素数１〜３のアルキル基を示し、それぞれの式（４−１）〜（４−４）において、Ｒ^１〜Ｒ^１０の少なくとも１つは炭素数１〜３のアルキル基である。）

(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 are respectively formulas (4-1) to (4-4). In 4), ^{at least one of R 1 to} R ¹⁰ is an alkyl group having 1 to 3 carbon atoms.)

As the linear alkylene ether unit (P1) represented by the general formula (3), when it is described as glycol, ethylene glycol having p of 2, trimethylene glycol having p of 3, and tetra having p of 4 are described. Examples thereof include methylene glycol, pentamethylene glycol having p of 5, hexamethylene glycol having p of 6, and these may be mixed, preferably trimethylene glycol and tetramethylene glycol, and tetramethylene glycol is particularly preferable.

Trimethylene glycol is industrially obtained by hydroformylation of ethylene oxide to obtain 3-hydroxypropionaldehyde, which is hydrogenated, or 3-hydroxypropionaldehyde obtained by hydrating acrolein is hydrogenated with a Ni catalyst. Manufactured by the method. Recently, glycerin, glucose, starch and the like have been reduced to microorganisms to produce trimethylene glycol by a biomethod.

When this is described as glycol as the branched alkylene ether unit represented by the above general formula (4-1), (2-methyl) ethylene glycol, (2-ethyl) ethylene glycol, (2,2-dimethyl) ethylene glycol, etc. These may be mixed, and (2-methyl) ethylene glycol and (2-ethyl) ethylene glycol are preferable.

When this is described as glycol as the branched alkylene ether unit represented by the above general formula (4-2), (2-methyl) trimethylene glycol, (3-methyl) trimethylene glycol, (2-ethyl) trimethylene glycol , (3-Eethyl) triethylene glycol, (2,2-dimethyl) trimethylene glycol, (2,2-methylethyl) trimethylene glycol, (2,2-diethyl) trimethylene glycol (ie, neopentyl glycol) , (3,3-dimethyl) trimethylene glycol, (3,3-methylethyl) trimethylene glycol, (3,3-diethyl) trimethylene glycol and the like, and these may be mixed.

When this is described as glycol as the branched alkylene ether unit represented by the above general formula (4-3), (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 and the like, and these may be mixed, and (3-methyl) tetramethylene glycol may be used. preferable.

When this is described as glycol as the branched alkylene ether unit represented by the above general formula (4-4), (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, (5,5) -Dimethyl) pentamethylene glycol, (5,5-methylethyl) pentamethylene glycol, (5,5-diethyl) pentamethylene glycol and the like can be mentioned, and these may be mixed.

As described above, the units represented by the general formulas (4-1) to (4-4) constituting the branched alkylene ether unit have been described by using glycol as an example for convenience, but are not limited to these glycols and these alkylene oxides. Alternatively, these polyether-forming derivatives may be used.

As a preferable polyalkylene glycol copolymer, a copolymer composed of a tetramethylene ether unit and a unit represented by the general formula (4-3) is preferable, and a tetramethylene ether unit and 3-methyltetramethylene are particularly preferable. A copolymer composed of ether units is more preferable. Further, a copolymer composed of a tetramethylene ether unit and a unit represented by the general formula (4-1) is also preferable, and in particular, a copolymer composed of a tetramethylene ether unit and a 2-methylethylene ether unit, and a tetramethylene ether. A copolymer composed of a unit and a 2-ethylethylene ether unit is more preferable. Further, a copolymer composed of a tetramethylene ether unit and the general formula (4-2) is also preferable, and a copolymer composed of a 2,2-dimethyltrimethylene ether unit, that is, a neopentyl glycol ether unit 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. ) Is a molar ratio of (P1) / (P2), preferably 95/5 to 5/95, more preferably 93/7 to 40/60, and even more preferably 90/10. It is ~ 65/35, and it is more preferable that the linear alkylene ether unit (P1) is rich.
The mole fraction is ^{measured using a 1} H-NMR measuring device using deuterated chloroform as a solvent.

Among the above, particularly preferable polyalkylene glycols include homopolymers such as polytrimethylene glycol, poly (2-methyl) ethylene glycol, poly (2-ethyl) ethylene glycol, and polytetramethylene glycol, and polytetramethylene glycol-. Polyethylene glycol, polytetramethylene glycol-polytrimethylene glycol, polytetramethylene glycol-poly (2-methyl) ethylene glycol, polytetramethylene glycol-poly (3-methyl) tetramethylene glycol, polytetramethylene glycol-poly (2) Examples thereof include copolymers of -ethyl) ethylene glycol, polytetramethylene glycol-polyneopentyl glycol, polyethylene glycol-polytrimethylene glycol, polyethylene glycol-poly (2-methyl) ethylene glycol and the like.

Further, as the polyalkylene glycol, even if one end or both ends thereof are sealed with a carboxylic acid or an alcohol, the performance development is not affected, and an esterified product or an etherified product can be used in the same manner. X and / or Y in the formulas (1) and (2) are an aliphatic acyl group having 2 to 23 carbon atoms, an alkyl group having 1 to 23 carbon atoms, an aryl group having 6 to 22 carbon atoms, or 7 to 23 carbon atoms. It may be an arylkill group of.

Examples of the esterified product include fatty acid esters, and either linear or branched fatty acid esters can be used, and the fatty acids constituting the fatty acid esters may be saturated fatty acids or unsaturated fatty acids. Further, those in which some hydrogen atoms are substituted with a substituent such as a hydroxyl group can also be used.
The fatty acids constituting the fatty acid ester include monovalent or divalent fatty acids having 1 to 23 carbon atoms, for example, monovalent saturated fatty acids, specifically, formic acid, acetic acid, propionic acid, butyric acid, valeric acid, and caproic acid. , Enantic acid, capric acid, capric acid, lauric acid, myristic acid, pentadecylic acid, palmitic acid, heptadecic acid, stearic acid, nonadecanic acid, arachidic acid, behenic acid and monovalent unsaturated fatty acids, specifically, 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, and tetradecanedioic acid. , Tapsiaic acid and decenoic acid, undecenoic acid, dodecenoic acid and the like.
These fatty acids can be used alone or in combination of two or more. The fatty acid also includes a fatty acid having one or more hydroxyl groups in the molecule.

As a preferable specific example of the fatty acid ester of polyalkylene glycol, in the general formula (1), R is a methyl group, X and Y are aliphatic acyl groups having 18 carbon atoms, polypropylene glycol stearate, R is a methyl group, and X. And polypropylene glycol behenate in which Y is an aliphatic acyl group having 22 carbon atoms. Preferred specific examples of the fatty acid ester of the linear polyalkylene glycol are polyalkylene glycol monopalmitic acid ester, polyalkylene glycol dipalmitic acid ester, polyalkylene glycol monostearic acid ester, polyalkylene glycol distearate, and polyalkylene glycol. Examples thereof include (monopalmitic acid / monostearic acid) ester and polyalkylene glycol behenate.

The alkyl group constituting the alkyl ether of the polyalkylene glycol may be linear or branched, and has, for example, the number of carbon atoms such as a methyl group, an ethyl group, a propyl group, a butyl group, an octyl group, a lauryl group, and a stearyl group. Examples thereof include alkyl groups 1 to 23, and examples of such polyalkylene glycols include alkylmethyl ethers, ethyl ethers, butyl ethers, lauryl ethers, and stearyl ethers of polyalkylene glycols.

The aryl group constituting the aryl ether of the polyalkylene glycol is preferably an aryl group having 6 to 22 carbon atoms, more preferably 6 to 12 carbon atoms, and further preferably 6 to 10 carbon atoms, for example, a phenyl group or a tolyl. Examples thereof include a group and a naphthyl group, and a phenyl group, a tolyl group and the like are preferable. Further, since the end-sealing group exhibits good compatibility with polycarbonate even if it is an aralkyl group, it can exhibit the same action as an aryl group, and the aralkyl group preferably has 7 to 23 carbon atoms. An aralkyl group having 7 to 13 carbon atoms, more preferably 7 to 11 carbon atoms is preferable, and examples thereof include a benzyl group and a phenethyl group, and a benzyl group is particularly preferable.

The number average molecular weight of the polyalkylene glycol (B) is preferably 500 to 5000, more preferably 600 or more, still more preferably 700 or more, still more preferably 4000 or less, still more preferably 3000 or less, and particularly preferably 3000 or less. It is 2000 or less. If it exceeds the upper limit of the above range, the compatibility is lowered, which is not preferable, and if it is less than the lower limit of the above range, gas is likely to be generated during molding, which is not preferable.
The number average molecular weight of the polyalkylene glycol is a number average molecular weight calculated based on the hydroxyl value measured in accordance with JIS K1577.

One type of polyalkylene glycol (B) may be used alone, or two or more types may be used in combination.

As described above, the content of the polyalkylene glycol (B) is 0.1 to 4 parts by mass with respect to 100 parts by mass of the polycarbonate resin (A), but is preferably 0.15 parts by mass or more, more preferably 0.15 parts by mass or more. 0.2 parts by mass or more, more preferably 0.25 parts by mass or more, preferably 3.5 parts by mass or less, more preferably 3 parts by mass or less, still more preferably 2.5 parts by mass or less, especially 2 parts by mass. Below, it is particularly preferable that it is 1.5 parts by mass or less, particularly 1 part by mass or less.

[Phosphorus stabilizer (C)]
The polycarbonate resin composition for optical components of the present invention contains a phosphorus-based stabilizer. By containing a phosphorus-based stabilizer, the hue of the polycarbonate resin composition of the present invention is further improved, and the heat-resistant discoloration property is further improved.
Any known phosphorus-based stabilizer can be used. Specific examples include phosphoric acid, phosphonic acid, phosphite, phosphinic acid, polyphosphoric acid and other phosphorus oxo acids; acidic sodium pyrophosphate, potassium pyrophosphate, acidic calcium pyrophosphate and other acidic pyrophosphate metal salts; phosphoric acid. Phosphates of Group 1 or Group 2B metals such as potassium, sodium phosphate, cesium phosphate, zinc phosphate; phosphate compounds, phosphite compounds, phosphonite compounds and the like can be mentioned, with phosphite compounds being particularly preferred. By selecting the phosphite compound, a polycarbonate resin composition having higher discoloration resistance and continuous productivity can be 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.
Examples of such phosphite compounds include triphenyl phosphite, tris (monononylphenyl) phosphite, tris (monononyl / dinonyl-phenyl) phosphite, and tris (2,4-di-tert-butylphenyl) phos. Fight, monooctyldiphenylphosphite, dioctylmonophenylphosphite, monodecyldiphenylphosphite, didecylmonophenylphosphite, tridecylphosphite, trilaurylphosphite, tristearylphosphite, distearylpentaerythritol diphosphite, Bis (2,4-di-tert-butyl-4-methylphenyl) pentaerythritol phosphite, bis (2,6-di-tert-butylphenyl) octylphosphite, 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-methyl) Phenyl) propoxy] -2,4,8,10-tetra-tert-butyldibenzo [d, f] [1,3,2] -dioxaphosfepine and the like.

Among such phosphite compounds, the aromatic phosphite compound represented by the following formula (5) or (6) is more preferable because the heat-resistant discoloration property of the polycarbonate resin composition of the present invention is effectively enhanced.

（式中、Ｒ^１、Ｒ^２及びＲ^３は、それぞれ同一であっても異なっていてもよく、炭素数６以上３０以下のアリール基を表す。）

(In the formula, R ¹ , R ² and R ³ may be the same or different, respectively, and represent an aryl group having 6 or more and 30 or less carbon atoms.)

（式中、Ｒ^４及びＲ^５は、それぞれ同一であっても異なっていてもよく、炭素数６以上３０以下のアリール基を表す。）

(In the formula, R ⁴ and R ⁵ may be the same or different, respectively, and represent an aryl group having 6 or more and 30 or less carbon atoms.)

As the phosphite compound represented by the above formula (5), triphenylphosphine, tris (monononylphenyl) phosphite, tris (2,4-di-tert-butylphenyl) phosphite and the like are preferable, and among them, triphenylphosphine and tris (2,4-di-tert-butylphenyl) phosphite are preferable. Tris (2,4-di-tert-butylphenyl) phosphite is more preferred. Specific examples of such an organic phosphite compound include "ADEKA STAB 1178" manufactured by ADEKA, "Sumilyzer TNP" manufactured by Sumitomo Chemical Co., Ltd., "JP-351" manufactured by Johoku Chemical Industry Co., Ltd., and "ADEKA STAB" manufactured by ADEKA Corporation. 2112 ”,“ Irgaphos 168 ”manufactured by BASF,“ JP-650 ”manufactured by Johoku Chemical Industry Co., Ltd., and the like.

Examples of the phosphite compound represented by the above formula (6) include bis (2,4-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite and bis (2,6-di-tert-butyl). Those having a pentaerythritol diphosphite structure such as -4-methylphenyl) pentaerythritol diphosphite and bis (2,4-dicumylphenyl) pentaerythritol diphosphite are particularly preferable. Specific examples of such an organic phosphite compound include "ADEKA STAB PEP-24G" and "ADEKA STAB PEP-36" manufactured by ADEKA, and "Doverphos S-9228" manufactured by Doverchemical.

Among the phosphite compounds, the aromatic phosphite compound represented by the above formula (6) is more preferable because it has a more excellent hue.
The phosphorus-based stabilizer may contain one type or two or more types in any combination and ratio.

The content of the phosphorus-based stabilizer (C) is 0.005 to 0.5 parts by mass, preferably 0.007 parts by mass or more, and more preferably 0. parts by mass with respect to 100 parts by mass of the polycarbonate resin (A). 008 parts by mass or more, particularly preferably 0.01 parts by mass or more, preferably 0.4 parts by mass or less, more preferably 0.3 parts by mass or less, still more preferably 0.2 parts by mass or less, particularly 0. . 1 part by mass or less. If the content of the phosphorus-based stabilizer (C) is less than 0.005 parts by mass, the hue and heat-resistant discoloration will be insufficient, and if it exceeds 0.5 parts by mass, the heat-resistant discoloration will only worsen. Not only that, but also the wet and thermal stability is reduced.

[Epoxy compound]
It is also preferable that the resin composition of the present invention contains an epoxy compound. By containing the epoxy compound together with the polyalkylene glycol (B) and the phosphorus-based stabilizer (C), the heat-resistant discoloration property can be further improved.

As the epoxy compound, a compound having one or more epoxy groups in one molecule is used. Specifically, phenylglycidyl ether, allylglycidyl ether, t-butylphenylglycidyl 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, cyclohexylmethyl 3,4-epoxycyclohexylcarboxylate, 3,4-epoxy-6-methylcyclohexylmethyl-6'-methylsilohexyl Carboxylate, bisphenol-A diglycidyl ether, tetrabromobisphenol-A glycidyl ether, diglycidyl ester of phthalic acid, diglycidyl ester of hexahydrophthalic acid, bis-epoxydicyclopentadienyl ether, bis-epoxyethylene glycol, Bis-epoxycyclohexyl adipate, butadiene diepoxide, tetraphenylethylene epoxide, octyl epoxide, 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-epoxycyclohexyl Carboxylate, Cyclohexyl-2-methyl-3,4-epoxycyclohexylcarboxylate, N-butyl-2-isopropyl-3,4-epoxy-5-methylcyclohexylcarboxylate, octadecyl-3,4-epoxycyclohexylcarboxylate, 2-Epoxyhexyl-3', 4'-epoxycyclohexylcarboxylate, 4,6-dimethyl-2,3-epoxycyclohexyl-3', 4'-epoxycyclohexylcarboxylate, 4,5-epoxy anhydride tetrahydrophthalic acid, 3 -T-butyl-4,5-epoxy anhydride tetrahydrophthalic acid, diethyl4,5-epoxy-cis-1,2-cyclohexyldicarboxy Preferable examples include rates, di-n-butyl-3-t-butyl-4,5-epoxy-cis-1,2-cyclohexyldicarboxylate, epoxidized soybean oil, epoxidized linseed oil and the like.
The epoxy compounds may be used alone or in combination of two or more.

Of these, alicyclic epoxy compounds are preferably used, with 3,4-epoxycyclohexylmethyl-3', 4'-epoxycyclohexylcarboxylate being particularly preferred.

The preferable content of the epoxy compound is 0.0005 to 0.2 parts by mass, more preferably 0.001 parts by mass or more, and further preferably 0.003 parts by mass with respect to 100 parts by mass of the polycarbonate resin (A). As described above, it is particularly preferably 0.005 parts by mass or more, more preferably 0.15 parts by mass or less, still more preferably 0.1 parts by mass or less, and particularly preferably 0.05 parts by mass or less.

[Additives, etc.]
The polycarbonate resin composition for optical components of the present invention includes other additives other than those described above, such as a mold release agent, an antioxidant, an ultraviolet absorber, a fluorescent whitening agent, a pigment, a dye, and other than the polycarbonate resin. It can contain additives such as polymers, flame retardants, impact modifiers, antistatic agents, plasticizers and compatibilizers. These additives may be used alone or in combination of two or more.

[Manufacturing method of polycarbonate resin composition]
The method for producing the polycarbonate resin composition itself is not limited, and a known method for producing the polycarbonate resin composition can be widely adopted. Polycarbonate resin (A), polyalkylene glycol (B), phosphorus-based stabilizer (C), and phosphorus-based stabilizer (C), and Other ingredients to be blended as needed are premixed using various mixers such as a tumbler and a Henschel mixer, and then a vanbury mixer, a roll, a brabender, a single-screw kneading extruder, a twin-screw kneading extruder, and a kneader. Examples thereof include a method of melt-kneading with a mixer such as. The temperature of melt-kneading is not particularly limited, but is usually in the range of 240 to 320 ° C.

The polycarbonate resin composition of the present invention can produce various molded products by molding pellets obtained by pelletizing the above-mentioned polycarbonate resin composition by various molding methods. It is also possible to directly mold the resin melt-kneaded by an extruder without passing through pellets to obtain a molded product.

Since the polycarbonate resin composition of the present invention has good hue, crack resistance during molding, excellent fluidity and high light transmittance, optical parts, particularly thin-walled optical parts, are molded by an injection molding method. It is preferably used to. The resin temperature at the time of injection molding is preferably higher than 260 to 300 ° C., which is a temperature generally applied to injection molding of polycarbonate resin, particularly in the case of thin-walled molded products, and is preferably 305. A resin temperature of ~ 400 ° C. is preferable. The resin temperature is more preferably 310 ° C. or higher, further preferably 315 ° C. or higher, particularly preferably 320 ° C. or higher, and even more preferably 390 ° C. or lower. When a conventional polycarbonate resin composition is used, there is a problem that yellowing of the molded product is likely to occur if the resin temperature at the time of molding is raised in order to mold the thin-walled molded product. However, the resin of the present invention has a problem. By using the composition, it becomes possible to produce a molded product having a good hue, particularly a thin-walled optical component, even in the above temperature range. Further, although it has been conventionally practiced to reduce the molecular weight of the polycarbonate resin in order to mold a thin-walled molded product, since the polycarbonate resin composition of the present invention has good fluidity, thin-wall molding can be performed without lowering the molecular weight. , It becomes possible to make a molded product with higher strength.
If it is difficult to measure the resin temperature directly, the resin temperature is grasped as the barrel set temperature.

Here, the thin-walled molded product means a molded product having a plate-shaped portion having a wall thickness of 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 a flat plate or a curved plate, may have a flat surface, may have irregularities or the like on the surface, and may have an inclined surface in cross section. It may have a wedge-shaped cross section or the like.

Examples of the optical component include components of devices / appliances that directly or indirectly use a light source such as an LED, an organic EL, an incandescent light bulb, a fluorescent lamp, and a cathode ray tube.
The optical component using the polycarbonate resin composition for an optical component of the present invention can be suitably used in the fields of a liquid crystal backlight unit, various display devices, and a lighting device. Examples of such devices include various mobile terminals such as mobile phones, mobile notebooks, netbooks, slate PCs, tablet PCs, smartphones, tablet terminals, cameras, watches, notebook computers, various displays, lighting devices, and the like. Be done.

Hereinafter, the present invention will be described in more detail with reference to Examples. However, the present invention is not construed as being limited to the following examples.
The raw materials and evaluation methods used in the following examples and comparative examples are as follows.

The polyalkylene glycols (B1) to (B3) in the above table are pH-adjusted products obtained by subjecting the above-mentioned raw material polyalkylene glycols to the following acid treatment.
The pH of each raw material polyalkylene glycol was adjusted by dissolving a required amount of 0.01 mol / L hydrochloric acid in a mixed solution of 2-propanol: water = 10: 6 (volume ratio). The solvent was removed from the obtained solution by a reduced pressure treatment at 60 ° C., and the solution was further dried at 120 ° C. for 10 hours to obtain a pH-adjusted polyalkylene glycol.

(Examples 1 to 7, Comparative Examples 1 to 2)
[Manufacturing of resin composition pellets]
Each component listed in Table 1 is blended in the proportion (part by mass) shown in Table 2 below, mixed in a tumbler for 20 minutes, and then a single-screw extruder with a vent having a screw diameter of 40 mm (manufactured by Tanabe Plastic Machinery Co., Ltd.). "VS-40") was melt-kneaded at a cylinder temperature of 240 ° C., and pellets were obtained by strand cutting.

[Measurement of hue (YI)]
The obtained pellets are dried at 120 ° C. for 5 to 7 hours with a hot air circulation type dryer, and then by an injection molding machine (“EC100SX-2A” manufactured by Toshiba Machine Co., Ltd.) at a resin temperature of 340 ° C. and a mold temperature of 80 ° C. , A long optical path molded product (300 mm × 7 mm × 4 mm) was molded.
For this long optical path molded product, YI (yellowing degree) was measured with an optical path length of 300 mm. A long optical path spectroscopic transmission chromometer (“ASA 1” manufactured by Nippon Denshoku Industries Co., Ltd., C light source, 2 ° field of view) was used for the measurement.

[Molded product cracking rate (unit:%)]
The obtained pellets are dried at 120 ° C. for 5 to 7 hours with a hot air circulation type dryer, and then by an injection molding machine (“HSP100A” manufactured by Sodick Co., Ltd.) at a resin temperature of 380 ° C. and a mold temperature of 60 ° C., 112 mm × 100 sheets of 61 mm × 0.4 mm molded products were molded. The number of molded products in which cracks were generated during molding was counted, and the crack occurrence rate (%) was calculated.
The above evaluation results are shown in Table 2 below.

Since the polycarbonate resin composition for optical parts of the present invention is a polycarbonate resin material having a good hue and improved cracking problems during molding, it can be suitably used for various optical parts and the like.

Claims (6)

With respect to 100 parts by mass of the polycarbonate resin (A), 0.1 to 4 parts by mass of polyalkylene glycol (B) having a pH of less than 7.0 measured according to JIS K1557-5 and a phosphorus-based stabilizer ( C) a 0.005 weight parts containing to that made of a light engine's service life for the polycarbonate resin composition thickness thin molded article having the following plate-like portion 1 mm. A thin-walled molded product having a plate-like portion having a wall thickness of 1 mm or less, which comprises the polycarbonate resin composition for optical parts according to claim 1, wherein the pH of the polyalkylene glycol (B) is in the range of 3.0 or more and less than 7.0. A thin-walled molded product having a plate-like portion having a wall thickness of 1 mm or less, which comprises the polycarbonate resin composition for optical parts according to claim 1 or 2, wherein the polyalkylene glycol (B) is a polyalkylene glycol having a propylene glycol unit. A thin-walled molded product having a plate-like portion having a wall thickness of 1 mm or less, which comprises the polycarbonate resin composition for optical parts according to claim 1 or 2, wherein the polyalkylene glycol (B) is a polyalkylene glycol having a tetramethylene glycol unit. The pH polyalkylene glycol which has been adjusted with hydrochloric acid or phosphoric acid so that a range of less than 3.0 or more 7.0 (B), in any of請Motomeko 1-4 you blending a polycarbonate resin (A) A method for producing a thin-walled molded product having a plate-shaped portion having a wall thickness of 1 mm or less, in which the above-described polycarbonate resin composition for optical parts is injection-molded at a resin temperature of 305 to 400 ° C. polyalkylene glycols pH is 7.0 or more, 305 to the optical component polycarbonate resin composition according to claim 5 using a polyalkylene glycol which is adjusted to a range of less than pH3.0 or 7.0 (B) A method for producing a thin-walled molded product having a plate-shaped portion having a wall thickness of 1 mm or less, which is injection-molded at a resin temperature of 400 ° C.