JP2017197704A - Polycarbonate resin composition and optical molded article - Google Patents

Abstract

CONSTITUTION: There are provided a polycarbonate resin composition which contains 0.005-3.0 pts.wt. of specific one-terminal alkylated polyalkylene glycol (B) and 0.005-1.0 pts.wt. of a phosphorous ester compound (C) with respect to 100 pts.wt. of a polycarbonate resin (A), and an optical molded article such as a light guide plate formed of the same.EFFECT: A polycarbonate resin composition is excellent, particularly, in brightness, light beam transmittance and hue stability without impairing characteristics inherent to a polycarbonate resin, specifically, mechanical properties and heat resistance, and accordingly prevents a hue from changing in molding of a thin (thickness of approximately 0.3 mm) light guide plate and prevents a resin itself from deteriorating.SELECTED DRAWING: None

Description

  The present invention relates to a polycarbonate resin composition and an optical molded article.

  For example, as disclosed in Patent Document 1, a planar light source device incorporated in a liquid crystal display device includes a light guide plate.

  Conventionally, polymethyl methacrylate (hereinafter referred to as PMMA) has been used as a material for the light guide plate. However, replacement of PMMA with polycarbonate resin has been promoted because it has high heat resistance and high mechanical strength. Yes.

  A polycarbonate resin is superior in mechanical properties, thermal properties, and electrical properties to PMMA, but slightly inferior in light transmittance. Accordingly, the planar light source device using the light guide plate made of polycarbonate resin has a problem that the luminance is lower than that using the light guide plate made of PMMA.

  Therefore, as disclosed in, for example, Patent Documents 2 to 6, a resin composition in which a polycarbonate resin and another material are used together in order to obtain a light transmittance equal to or higher than that of PMMA and improve the luminance of the light guide plate. Various proposals have been made.

  However, the resin compositions disclosed in Patent Documents 2 to 6 cannot sufficiently satisfy the recent demands as a material for the light guide plate.

JP-A-10-055712 Japanese Patent Laid-Open No. 09-020860 JP-A-11-158364 JP 2001-215336 A JP 2004-051700 A International Publication No. 2011/088335

  The present invention provides a polycarbonate resin composition that does not impair the properties such as heat resistance and mechanical strength inherent to the polycarbonate resin, has high light transmittance, and has excellent light transmittance even when molded at a high temperature. provide. In addition, the present invention provides an optical molded article that is molded from the polycarbonate resin composition and has high brightness, small yellowness, excellent hue, and excellent brightness and hue even when molded at a high temperature. .

  As a result of intensive studies to solve such problems, the present inventors have made the polycarbonate resin contain a specific one-end alkylated polyalkylene glycol and a phosphite-based compound, thereby increasing the light transmittance. The present invention was completed by finding that optical molded articles such as a light guide plate having a good hue and luminance can be obtained.

That is, the present invention relates to 0.005 to 3.0 parts by weight of a single-end alkyl group-containing polyalkylene glycol (B) represented by the following general formula (1) and 100 parts by weight of a polycarbonate resin (A). The present invention relates to a polycarbonate resin composition and a molded article for optical use such as a light guide plate comprising 0.005 to 1.0 part by weight of a phosphoric ester compound (C).
General formula (1):
R′O— (CHR—CH ₂ O) n—H (1)
(In the formula, R represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, R ′ represents an alkyl group having 1 to 30 carbon atoms, and n represents an integer of 3 to 60.)

  The polycarbonate resin composition of the present invention does not impair the properties such as heat resistance and mechanical strength inherent to the polycarbonate resin, has high light transmittance, and excellent light transmittance even when molded at a high temperature. Is. The molded article for optics in the present invention is formed by molding the polycarbonate resin composition, and has high brightness, small yellowness, excellent hue, and excellent brightness and hue even when molded at high temperatures. is there. Therefore, even if it is a thin light guide plate with a thickness of about 0.3 mm, for example, the hue changes and the appearance deteriorates, and the resin itself is less likely to deteriorate through high temperature molding. high.

  Hereinafter, embodiments will be described in detail. However, more detailed explanation than necessary may be omitted. For example, detailed descriptions of already well-known matters and repeated descriptions for substantially the same configuration may be omitted. This is to avoid the following description from becoming unnecessarily redundant and to facilitate understanding by those skilled in the art.

  The inventors provide the following explanation for those skilled in the art to fully understand the present invention, and are not intended to limit the claimed subject matter.

(Embodiment 1: Polycarbonate resin composition)
The polycarbonate resin composition according to Embodiment 1 is obtained by blending a specific one-terminal alkylated polyalkylene glycol (B) and a phosphite compound (C) with a polycarbonate resin (A). In addition, you may mix | blend another component with the polycarbonate resin composition used by this invention as needed.

  The polycarbonate resin (A) is a polymer obtained by a phosgene method in which various dihydroxydiaryl compounds and phosgene are reacted, or a transesterification method in which a dihydroxydiaryl compound and a carbonate such as diphenyl carbonate are reacted. A typical example is a polycarbonate resin produced from 2,2-bis (4-hydroxyphenyl) propane (bisphenol A).

  As the dihydroxydiaryl compound, in addition to bisphenol A, for example, bis (4-hydroxyphenyl) methane, 1,1-bis (4-hydroxyphenyl) ethane, 2,2-bis (4-hydroxyphenyl) butane, 2,2-bis (4-hydroxyphenyl) octane, bis (4-hydroxyphenyl) phenylmethane, 2,2-bis (4-hydroxyphenyl-3-methylphenyl) propane, 1,1-bis (4-hydroxy) -3-tert-butylphenyl) propane, 2,2-bis (4-hydroxy-3-bromophenyl) propane, 2,2-bis (4-hydroxy-3,5-dibromophenyl) propane, 2,2- Bis (hydroxyaryl) alkanes such as bis (4-hydroxy-3,5-dichlorophenyl) propane; -Bis (hydroxyaryl) cycloalkanes such as bis (4-hydroxyphenyl) cyclopentane and 1,1-bis (4-hydroxyphenyl) cyclohexane; 4,4'-dihydroxydiphenyl ether, 4,4'-dihydroxy-3 Dihydroxy diaryl ethers such as 4,3'-dimethyldiphenyl ether; dihydroxy diaryl sulfides such as 4,4'-dihydroxydiphenyl sulfide; 4,4'-dihydroxydiphenyl sulfoxide, 4,4'-dihydroxy-3,3'-dimethyl Dihydroxy diaryl sulfoxides such as diphenyl sulfoxide; dihydroxy diaryl sulfones such as 4,4′-dihydroxydiphenyl sulfone and 4,4′-dihydroxy-3,3′-dimethyldiphenyl sulfone; These may be used alone or in admixture of two or more. In addition to these, piperazine, dipiperidyl hydroquinone, resorcin, 4,4′-dihydroxydiphenyl, and the like may be mixed and used.

  Furthermore, you may mix and use the said dihydroxy diaryl compound and the trivalent or more phenol compound shown below, for example.

  Examples of the trivalent or higher phenol compound include phloroglucin, 4,6-dimethyl-2,4,6-tri- (4-hydroxyphenyl) -heptene, 2,4,6-dimethyl-2,4,6. -Tri- (4-hydroxyphenyl) -heptane, 1,3,5-tri- (4-hydroxyphenyl) -benzol, 1,1,1-tri- (4-hydroxyphenyl) -ethane and 2,2- Bis- [4,4- (4,4′-dihydroxydiphenyl) -cyclohexyl] -propane and the like.

  The viscosity average molecular weight of the polycarbonate resin (A) is preferably 10,000 to 100,000, more preferably 12,000 to 30,000. In addition, when manufacturing such a polycarbonate resin (A), a molecular weight regulator, a catalyst, etc. can be used as needed.

One terminal alkyl group polyalkylene glycol (B) is represented by the following general formula (1).
General formula (1):
R′O— (CHR—CH ₂ O) _n —H (1)
(In the formula, R represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, R ′ represents an alkyl group having 1 to 30 carbon atoms, and n represents an integer of 3 to 60.)

  In addition, the polyalkylene glycol (B) having a single terminal alkyl group represented by the general formula (1) has an appropriate lipophilicity and is therefore excellent in compatibility with the polycarbonate resin (A). The transparency of the molded product obtained from the polycarbonate resin composition containing glycol (B) is also improved.

  Furthermore, by blending the one-end alkyl group-containing polyalkylene glycol (B) represented by the general formula (1), it is possible to suppress generation of unnecessary shear heat when molding the polycarbonate resin composition. In addition, the polycarbonate resin composition can be provided with releasability, so that it is not necessary to separately add a release agent such as a polyorganosiloxane compound.

  It is preferable that the weight average molecular weight of the said one terminal alkyl group-ized polyalkylene glycol (B) is 1000-4000. When the weight average molecular weight of the one-end alkylated polyalkylene glycol (B) is less than 1000, a sufficient effect of improving the light transmittance may not be expected. Conversely, when the weight average molecular weight exceeds 4000, There is a possibility that the transmittance decreases and the fogging rate increases.

  Examples of commercially available one-end alkyl grouped polyalkylene glycols (B) include, for example, Unilube MS-70K (weight average molecular weight 1100), Unilube MB-11 (weight average molecular weight 1000) manufactured by NOF Corporation. ), Uniterminal MB-38 (weight average molecular weight 1900) and the like.

  The compounding amount of the one-terminal alkyl grouped polyalkylene glycol (B) is 0.005 to 3.0 parts by weight with respect to 100 parts by weight of the polycarbonate resin (A), 0.1 to 2.0 parts by weight, Furthermore, it is preferable that it is 0.5-1.5 weight part. When the blending amount of the one-end alkylated polyalkylene glycol (B) is less than 0.005 parts by weight, the effect of improving light transmittance and hue is insufficient, and conversely, the blending amount is 3.0 parts by weight. When exceeding, the light transmittance will fall and the clouding rate will rise.

  In the polycarbonate resin composition of the present invention, a phosphite compound (C) is blended together with the specific one-terminal alkylated polyalkylene glycol (B) represented by the general formula (1). Thus, the heat resistance, mechanical strength, etc. inherent to the polycarbonate resin (A) can be obtained by simultaneously blending the specific one-end alkyl grouped polyalkylene glycol (B) and the phosphite compound (C). Thus, a polycarbonate resin composition having improved light transmittance is obtained.

As the phosphite compound (C), for example, a compound represented by the following general formula (2) is particularly suitable.
General formula (2):

（式中、Ｒ^１は、炭素数１〜２０のアルキル基又はアルキル基で置換されていてもよいアリール基を示し、ａは、０〜３の整数を示す）

(In the formula, R ¹ represents an alkyl group having 1 to 20 carbon atoms or an aryl group which may be substituted with an alkyl group, and a represents an integer of 0 to 3)

In the general formula (2), R ¹ is an alkyl group having 1 to 20 carbon atoms, and more preferably an alkyl group having 1 to 10 carbon atoms.

  Examples of the compound represented by the general formula (2) include triphenyl phosphite, tricresyl phosphite, tris (2,4-di-t-butylphenyl) phosphite, and trisnonylphenyl phosphite. It is done. Among these, tris (2,4-di-t-butylphenyl) phosphite is particularly suitable. For example, Irgaphos 168 manufactured by BASF ("Irgaphos" is a registered trademark of BISF Societas Europea) is commercially available. Is available.

Examples of the phosphite compound (C) include compounds represented by the general formula (3) in addition to the compounds represented by the general formula (2).
General formula (3):

（式中、Ｒ^２、Ｒ^３、Ｒ^５及びＲ^６は、それぞれ独立して、水素原子、炭素数１〜８のアルキル基、炭素数５〜８のシクロアルキル基、炭素数６〜１２のアルキルシクロアルキル基、炭素数７〜１２のアラルキル基又はフェニル基を示す。Ｒ^４は、水素原子又は炭素数１〜８のアルキル基を示す。Ｘは、単結合、硫黄原子又は式：−ＣＨＲ^７−（ここで、Ｒ^７は、水素原子、炭素数１〜８のアルキル基又は炭素数５〜８のシクロアルキル基を示す）で表される基を示す。Ａは、炭素数１〜８のアルキレン基又は式：＊−ＣＯＲ^８−（ここで、Ｒ^８は、単結合又は炭素数１〜８のアルキレン基を示し、＊は、酸素側の結合手であることを示す）で表される基を示す。Ｙ及びＺは、いずれか一方がヒドロキシル基、炭素数１〜８のアルコキシ基又は炭素数７〜１２のアラルキルオキシ基を示し、もう一方が水素原子又は炭素数１〜８のアルキル基を示す）

(In the formula, R ² , R ³ , R ⁵ and R ⁶ are each independently a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, or an alkyl group having 6 to 12 carbon atoms. An alkylcycloalkyl group, an aralkyl group having 7 to 12 carbon atoms, or a phenyl group, R ⁴ represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms, X is a single bond, a sulfur atom, or a formula: —CHR; ^7- (wherein R ⁷ represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or a cycloalkyl group having 5 to 8 carbon atoms), and A represents a group having 1 to 8 carbon atoms. Or an alkylene group of the formula: * —COR ⁸ — (wherein R ⁸ represents a single bond or an alkylene group having 1 to 8 carbon atoms, and * represents a bond on the oxygen side). Y and Z are either a hydroxyl group or an alcohol having 1 to 8 carbon atoms. A xyl group or an aralkyloxy group having 7 to 12 carbon atoms, the other being a hydrogen atom or an alkyl group having 1 to 8 carbon atoms

In General Formula (3), R ² , R ³ , R ⁵ and R ⁶ are each independently a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, or 6 carbon atoms. -12 alkylcycloalkyl group, a C7-12 aralkyl group, or a phenyl group is shown.

  Here, examples of the alkyl group having 1 to 8 carbon atoms include methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl group, sec-butyl group, and t-butyl. Group, t-pentyl group, i-octyl group, t-octyl group, 2-ethylhexyl group and the like. Examples of the cycloalkyl group having 5 to 8 carbon atoms include a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group. Examples of the alkylcycloalkyl group having 6 to 12 carbon atoms include 1-methylcyclopentyl group, 1-methylcyclohexyl group, 1-methyl-4-i-propylcyclohexyl group and the like. Examples of the aralkyl group having 7 to 12 carbon atoms include benzyl group, α-methylbenzyl group, α, α-dimethylbenzyl group and the like.

R ² , R ³ and R ⁵ are each independently preferably an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms or an alkylcycloalkyl group having 6 to 12 carbon atoms. . In particular, R ² and R ⁵ are preferably each independently a t-alkyl group such as a t-butyl group, a t-pentyl group, or a t-octyl group, a cyclohexyl group, or a 1-methylcyclohexyl group. In particular, R ³ is a carbon number such as a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, an i-butyl group, a sec-butyl group, a t-butyl group, or a t-pentyl group. It is preferably an alkyl group of 1 to 5, more preferably a methyl group, a t-butyl group or a t-pentyl group.

R ⁶ is preferably a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or a cycloalkyl group having 5 to 8 carbon atoms, a hydrogen atom, a methyl group, an ethyl group, an n-propyl group, or an i-propyl group. , An n-butyl group, an i-butyl group, a sec-butyl group, a t-butyl group, a t-pentyl group, or the like, more preferably an alkyl group having 1 to 5 carbon atoms.

In General formula (3), R < ⁴ > shows a hydrogen atom or a C1-C8 alkyl group. As a C1-C8 alkyl group, the alkyl group illustrated by description of the said R < ² >, R < ³ >, R < ⁵ > and R < ⁶ > is mentioned, for example. In particular, R ⁴ is preferably a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and more preferably a hydrogen atom or a methyl group.

In General Formula (3), X represents a single bond, a sulfur atom, or a group represented by the formula: —CHR ⁷ —. Here, R ⁷ in the formula: —CHR ⁷ — represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or a cycloalkyl group having 5 to 8 carbon atoms. Examples of the alkyl group having 1 to 8 carbon atoms and the cycloalkyl group having 5 to 8 carbon atoms include the alkyl groups and cycloalkyl groups exemplified in the description of R ² , R ³ , R ⁵ and R ⁶ , respectively. It is done. In particular, X is a single bond, a methylene group, or a methylene group substituted with a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, an i-butyl group, a t-butyl group, or the like. It is preferably a single bond, and more preferably a single bond.

In the general formula (3), A represents an alkylene group having 1 to 8 carbon atoms or a group represented by the formula: * —COR ⁸ —. Examples of the alkylene group having 1 to 8 carbon atoms include a methylene group, an ethylene group, a propylene group, a butylene group, a pentamethylene group, a hexamethylene group, an octamethylene group, and a 2,2-dimethyl-1,3-propylene group. And is preferably a propylene group. R ⁸ in the formula * -COR ⁸ — represents a single bond or an alkylene group having 1 to 8 carbon atoms. Examples of the alkylene group having 1 to 8 carbon atoms which indicates the R ^8, for example, alkylene groups exemplified in the description of the A. R ⁸ is preferably a single bond or an ethylene group. Further, * in the formula: * —COR ⁸ — is a bond on the oxygen side and indicates that the carbonyl group is bonded to the oxygen atom of the phosphite group.

In General Formula (3), one of Y and Z represents a hydroxyl group, an alkoxy group having 1 to 8 carbon atoms, or an aralkyloxy group having 7 to 12 carbon atoms, and the other is a hydrogen atom or 1 to 1 carbon atoms. 8 represents an alkyl group. As a C1-C8 alkoxy group, a methoxy group, an ethoxy group, a propoxy group, t-butoxy group, a pentyloxy group etc. are mentioned, for example. Examples of the aralkyloxy group having 7 to 12 carbon atoms include benzyloxy group, α-methylbenzyloxy group, α, α-dimethylbenzyloxy group and the like. As a C1-C8 alkyl group, the alkyl group illustrated by description of the said R < ² >, R < ³ >, R < ⁵ > and R < ⁶ > is mentioned, for example.

  Examples of the compound represented by the general formula (3) include 2,4,8,10-tetra-t-butyl-6- [3- (3-methyl-4-hydroxy-5-t-butylphenyl). Propoxy] dibenzo [d, f] [1,3,2] dioxaphosphine, 6- [3- (3,5-di-t-butyl-4-hydroxyphenyl) propoxy] -2,4,8 , 10-Tetra-t-butyldibenzo [d, f] [1,3,2] dioxaphosphine, 6- [3- (3,5-di-t-butyl-4-hydroxyphenyl) propoxy] -4,8-di-t-butyl-2,10-dimethyl-12H-dibenzo [d, g] [1,3,2] dioxaphosphocin, 6- [3- (3,5-di-t -Butyl-4-hydroxyphenyl) propionyloxy] -4,8-di-t-butyl-2, 0-dimethyl -12H- dibenzo [d, g] [1,3,2] dioxaphosphocin, and the like. Among these, 2,4,8,10-tetra-t-butyl-6- [3- (3-methyl-4) is particularly used when the obtained polycarbonate resin composition is used in a field where optical properties are required. -Hydroxy-5-t-butylphenyl) propoxy] dibenzo [d, f] [1,3,2] dioxaphosphine is suitable, for example, Sumitizer GP ("Smilizer") manufactured by Sumitomo Chemical Co., Ltd. Is commercially available as a registered trademark.

Examples of the phosphite compound (C) include, in addition to the compound represented by the general formula (2) and the compound represented by the general formula (3), for example, represented by the general formula (4). The compound which is made is mentioned.
General formula (4):

（式中、Ｒ^９及びＲ^１０は、それぞれ独立して、炭素数１〜２０のアルキル基又はアルキル基で置換されていてもよいアリール基を示し、ｂ及びｃは、それぞれ独立して、０〜３の整数を示す）

(Wherein R ⁹ and R ¹⁰ each independently represents an alkyl group having 1 to 20 carbon atoms or an aryl group optionally substituted with an alkyl group, and b and c each independently represents 0 Represents an integer of ~ 3)

  As the compound represented by the general formula (4), for example, ADK STAB PEP-36 (“ADEKA STAB” is a registered trademark) manufactured by ADEKA Corporation is commercially available.

  The compounding amount of the phosphite compound (C) is 0.005 to 1.0 parts by weight, 0.01 to 0.5 parts by weight, and further 0 to 100 parts by weight of the polycarbonate resin (A). It is preferable that it is 0.02-0.1 weight part. When the blending amount of the phosphite compound (C) is less than 0.005 parts by weight, the effect of improving light transmittance and hue is insufficient, and conversely, the blending amount exceeds 1.0 parts by weight. However, the effect of improving light transmittance and hue is insufficient.

  Furthermore, the polycarbonate resin composition according to Embodiment 1 has, for example, a heat stabilizer, an antioxidant, a colorant, a release agent, a softening agent, an antistatic agent, an impact within a range not impairing the effects of the present invention. Various additives such as a property improving agent, polymers other than the polycarbonate resin (A), and the like may be appropriately blended.

  The production method of the polycarbonate resin composition is not particularly limited, and the polycarbonate resin (A), the one-end alkyl group polyalkylene glycol (B), the phosphite compound (C), and the various additions as necessary. For polymers other than the agent and polycarbonate resin (A), the type and blending amount of each component is adjusted as appropriate, and these are mixed in a known mixer such as a tumbler or ribbon blender, or in an extruder. The method of melt-kneading is mentioned.

  As described above, the first embodiment has been described as an example of the technique disclosed in the present application. However, the technology according to the present invention is not limited to this, and can also be applied to embodiments in which changes, replacements, additions, omissions, etc. are made as appropriate.

(Embodiment 2: Optical molded product)
The optical molded product according to Embodiment 2 is formed by molding the polycarbonate resin composition according to Embodiment 1 obtained as described above.

  There is no particular limitation on the method for producing the optical molded product, and examples thereof include a method of molding a polycarbonate resin composition by a known injection molding method, compression molding method or the like.

  The optical molded product obtained as described above is suitable as, for example, a light guide plate, a surface light emitter material, and a name plate.

  As described above, the second embodiment has been described as an example of the technique disclosed in the present application. However, the technology in the present invention is not limited to this, and can also be applied to embodiments in which changes, replacements, additions, omissions, etc. are made as appropriate.

  EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. Unless otherwise specified, “part” and “%” are based on weight.

The following were used as raw materials.
1. Polycarbonate resin (A)
Polycarbonate resin synthesized from bisphenol A and carbonyl chloride Caliber 200-80
(Trade name, manufactured by Sumika Stylon Polycarbonate Co., Ltd., “Caliver” is a registered trademark of Stylon Europ GmbH, viscosity average molecular weight: 15000, hereinafter referred to as “PC”)

2. Polyalkylene glycol (B) one terminal group type Uni-Lube _{MS-70K C 17 H 35 O-} (CH (CH 3) -CH 2 O) n -H
(Trade name, manufactured by NOF Corporation, weight average molecular weight 1100: hereinafter referred to as “compound B1”)
Unilube MB-11 CH ₄ O— (CH (CH ₃ ) —CH ₂ O) _n —H
(Trade name, manufactured by NOF Corporation, weight average molecular weight 1000: hereinafter referred to as “compound B2”)

3. Phosphite compound (C)
3-1. Tris (2,4-di-t-butylphenyl) phosphite represented by the following formula

イルガフォス１６８（商品名、ＢＡＳＦ社製、以下「化合物Ｃ１」という）

Irgaphos 168 (trade name, manufactured by BASF, hereinafter referred to as “compound C1”)

3-2. 2,4,8,10-tetra-tert-butyl-6- [3- (3-methyl-4-hydroxy-5-tert-butylphenyl) propoxy] dibenzo [d, f ] [1, 3, 2] Dioxaphosphepine

スミライザーＧＰ（商品名、住友化学（株）製、以下「化合物Ｃ２」という）

Sumilizer GP (trade name, manufactured by Sumitomo Chemical Co., Ltd., hereinafter referred to as “Compound C2”)

3-3. 3,9-bis (2,6-di-t-butyl-4-methylphenoxy) -2,4,8,10-tetraoxa-3,9-diphosphaspiro [5,5] represented by the following formula Undeka

アデカスタブＰＥＰ−３６（商品名、（株）ＡＤＥＫＡ製、以下「化合物Ｃ３」という）

ADK STAB PEP-36 (trade name, manufactured by ADEKA Corporation, hereinafter referred to as “Compound C3”)

4). Other
4-1. Polypropylene glycol Both-terminal hydroxyl group type Uniol D-2000 H- (CH (CH ₃ ) -CH ₂ O) _n -H
(Trade name, manufactured by NOF Corporation, weight average molecular weight 2000: hereinafter referred to as “compound B′1”)

4-2. Both end stearate of polypropylene glycol Both end ester group type Unisafe NKL-9520
_{C 17 H 35 C (= O} ) - (CH (CH 3) -CH 2 O) n -C (= O) C 17 H 35
(Trade name, manufactured by NOF Corporation: hereinafter referred to as “Compound B′2”)

(1) First embodiment
Examples 1-13 and Comparative Examples 1-8
The raw materials were collectively put into a tumbler at the blending ratios shown in Tables 1 to 3, and after dry mixing for 10 minutes, using a twin screw extruder (manufactured by Nippon Steel Works, TEX30α), Melt kneading was performed at a melting temperature of 220 ° C. to obtain pellets of a polycarbonate resin composition.

  Using the obtained pellet, according to the following method, each test specimen for evaluation was produced and used for evaluation. The results are shown in Tables 1 to 3.

(Test piece preparation method)
The obtained pellets were dried at 120 ° C. for 4 hours or more, and then an injection molding machine (manufactured by FANUC, ROBOSHOT S2000i100A) was used at a molding temperature of 360 ° C. and a mold temperature of 80 ° C. The multipurpose test piece A type (length 168 mm × thickness 4 mm) defined in “Test piece” was produced. The end face of the test piece was cut, and the cut end face was mirror-finished using a resin plate end face mirror machine (Megaro Technica Co., Ltd., Plasticity PB-500).

(Evaluation method of integrated transmittance)
A spectrophotometer (manufactured by Hitachi, Ltd., UH4150) is equipped with a long optical path measurement accessory device, using a 50 W halogen lamp as a light source, a mask before light source 5.6 mm × 2.8 mm, a mask before sample 6.0 mm × In a state where 2.8 mm was used, the spectral transmittance in the direction of 168 mm in length of the test piece was measured every 1 nm in a wavelength range of 380 to 780 nm. The measured spectral transmittance was integrated and rounded off to the nearest tenth to obtain the total transmittance. The integrated transmittance was 30000 or more as good (indicated by ◯ in the table) and less than 30000 was defective (indicated by x in the table).

(Yellowness evaluation method)
Based on the spectral transmittance measured in the evaluation method of the accumulated transmittance, each yellow degree was obtained in a 10 degree visual field using a standard light source D65. The yellowness was 20 or less as good (indicated by ◯ in the table), and when it exceeded 20, it was determined as defective (indicated by x in the table).

  In the polycarbonate resin compositions of Examples 1 to 13, the polycarbonate resin (A) was added to the specific one-end alkylated polyalkylene glycol (B) represented by the general formula (1) and a phosphite compound ( C) are blended at specific ratios. Therefore, the test piece molded from the polycarbonate resin composition has a high integrated transmittance and a small yellowness.

  Thus, the polycarbonate resin compositions of Examples 1 to 13 do not impair the heat resistance inherent in the polycarbonate resin (A), have high light transmittance in the visible region, and are stable at high temperatures. Also excellent in properties. And the molded article which shape | molded such a polycarbonate resin composition has small yellowness, and is excellent in a hue, even when shape | molded at the high temperature of 360 degreeC.

  On the other hand, the polycarbonate resin composition of Comparative Example 1 is a case where the amount of the specific one-end alkylated polyalkylene glycol (B) is small, and the test piece molded at high temperature has a low integrated transmittance, and The yellowness was large. And the molded article which shape | molded such a polycarbonate resin composition has a large yellow degree, and is inferior to a hue.

  The polycarbonate resin composition of Comparative Example 2 is a case where the amount of the specific one-end alkylated polyalkylene glycol (B) is large, but the test piece molded at a high temperature has a low integrated transmittance and a yellowness. Was a big one. And the molded article which shape | molded such a polycarbonate resin composition has a large yellow degree, and is inferior to a hue.

  The polycarbonate resin composition of Comparative Example 3 was a case where the amount of the phosphite compound (C) was small, and the test piece molded at a high temperature had a low integrated transmittance.

  The polycarbonate resin composition of Comparative Example 4 was a case where the amount of the phosphite compound (C) was large, and the test piece molded at a high temperature had a low cumulative transmittance and a high yellowness. .

  The polycarbonate resin composition of Comparative Example 5 was a test in which the compound B′1 was contained instead of the specific one-end alkylated polyalkylene glycol (B) represented by the general formula (1) and molded at a high temperature. The piece had a low integrated transmittance and a high yellowness.

  The polycarbonate resin composition of Comparative Example 6 was a test molded at a high temperature when it contained compound B′1 instead of the specific one-end alkylated polyalkylene glycol (B) represented by the general formula (1). The piece had a low integrated transmittance and a high yellowness.

  The polycarbonate resin composition of Comparative Example 7 was a test in which the compound B′2 was contained instead of the specific one-end alkylated polyalkylene glycol (B) represented by the general formula (1) and molded at a high temperature. The piece had a low integrated transmittance and a high yellowness.

  A test in which the polycarbonate resin composition of Comparative Example 8 contained compound B′2 instead of the specific one-end alkylated polyalkylene glycol (B) represented by the general formula (1) and molded at a high temperature. The piece had a low integrated transmittance and a high yellowness.

  As described above, the embodiments have been described as examples of the technology in the present invention. To that end, a detailed explanation was provided.

  Accordingly, the components described in the detailed description include not only components essential for solving the problem but also components not essential for solving the problem in order to illustrate the above technique. obtain. Therefore, it should not be immediately recognized that these non-essential components are essential as the non-essential components are described in the detailed description.

  Moreover, since the above-mentioned embodiment is for demonstrating the technique in this invention, a various change, substitution, addition, abbreviation, etc. can be performed in a claim or its equivalent range.

  The polycarbonate resin composition of the present invention does not impair the heat resistance, mechanical strength and other properties inherent to the polycarbonate resin, is excellent in thermal stability and weather resistance, and also has a light transmittance even when molded at a high temperature. It is an excellent one. Therefore, even if it is a thin light guide plate with a thickness of about 0.3 mm, for example, the hue changes and the appearance deteriorates, and the resin itself is less likely to deteriorate through high temperature molding. high.

Claims (8)

One-terminal alkylated polyalkylene glycol (B) having a weight average molecular weight of 1000 to 4000 represented by the following general formula (1) with respect to 100 parts by weight of the polycarbonate resin (A): 0.005 to 3.0 parts by weight And a phosphite compound (C) in an amount of 0.005 to 1.0 part by weight, a polycarbonate resin composition.
General formula (1):
R′O— (CHR—CH ₂ O) _n —H (1)
(In the formula, R represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, R ′ represents an alkyl group having 1 to 30 carbon atoms, and n represents an integer of 3 to 60.) The polycarbonate resin, wherein the phosphite compound (C) is one or more compounds selected from the compounds represented by the following general formulas (2), (3) and (4) Composition.
General formula (2):

(In the formula, R ¹ represents an alkyl group having 1 to 20 carbon atoms or an aryl group which may be substituted with an alkyl group, and a represents an integer of 0 to 3)
General formula (3):

(In the formula, R ² , R ³ , R ⁵ and R ⁶ are each independently a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, or an alkyl group having 6 to 12 carbon atoms. An alkylcycloalkyl group, an aralkyl group having 7 to 12 carbon atoms, or a phenyl group, R ⁴ represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms, X is a single bond, a sulfur atom, or a formula: —CHR; ^7- (wherein R ⁷ represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or a cycloalkyl group having 5 to 8 carbon atoms), and A represents a group having 1 to 8 carbon atoms. Or an alkylene group of the formula: * —COR ⁸ — (wherein R ⁸ represents a single bond or an alkylene group having 1 to 8 carbon atoms, and * represents a bond on the oxygen side). Y and Z are either a hydroxyl group or an alcohol having 1 to 8 carbon atoms. A xyl group or an aralkyloxy group having 7 to 12 carbon atoms, the other being a hydrogen atom or an alkyl group having 1 to 8 carbon atoms
General formula (4):

(In formula, R < ⁹ >, R < ¹⁰ > is the C1-C20 alkyl group or the aryl group which may be substituted by the alkyl group, b and c show the integers 0-3.)   The polycarbonate resin composition according to claim 2, wherein the phosphite compound (C) represented by the general formula (2) is tris (2,4-di-t-butylphenyl) phosphite.   The phosphite compound (C) represented by the general formula (3) is 2,4,8,10-tetra-t-butyl-6- [3- (3-methyl-4-hydroxy-5- The polycarbonate resin composition according to claim 2, which is t-butylphenyl) propoxy] dibenzo [d, f] [1,3,2] dioxaphosphine.   The phosphite compound (C) represented by the general formula (4) is 3,9-bis (2,6-di-t-butyl-4-methylphenoxy) -2,4,8,10. The polycarbonate resin composition according to claim 2, which is tetraoxa-3,9-diphosphaspiro [5,5] undecane.   2. The polycarbonate resin composition according to claim 1, wherein the content of the phosphite compound (C) is 0.01 to 0.5 parts by weight with respect to 100 parts by weight of the polycarbonate resin (A).   The optical molded article containing the polycarbonate resin composition as described in any one of Claims 1-6.   The optical molded product according to claim 7, wherein the molded product is a light guide plate.