Polycarbonate resin composition and molded object

Abstract

This polycarbonate resin composition comprises a polycarbonate resin, a phosphorus-compound antioxidant, and an alicyclic epoxy compound. The phosphorus-compound antioxidant includes a pentaerythritol diphosphite compound. Per 100 parts by mass of the polycarbonate resin, the content of the alicyclic epoxy compound is 0.01-0.6 parts by mass, the content of the pentaerythritol diphosphite compound is 0.01-0.35 parts by mass, and the content of the phosphorus-compound antioxidant is 0.2 parts by mass or greater. The ratio of the content of the alicyclic epoxy compound to the content of the pentaerythritol diphosphite compound is 0.5 or higher.

Description

Polycarbonate resin composition and molded article

[0001] The present invention relates to a polycarbonate resin composition and a molded article containing the resin composition.

[0002] Polycarbonate resins such as aromatic polycarbonate resins are excellent in transparency, mechanical properties, thermal properties, electrical properties, etc., and by taking advantage of these properties, they are used in various optical molded products such as light guide members such as light guide plates, lenses, optical fibers, etc. In recent years, the use of polycarbonate resin compositions in daytime running lights or daytime running lamps (hereinafter, these may be collectively referred to as "DRLs") for vehicles, etc., or light guide parts that constitute the light guide portions of various optical components has also been considered.

[0003] Patent Document 1 discloses a polycarbonate resin composition for optical parts containing a polycarbonate resin (A), a polyether derivative (B), a phosphite ester compound (C), and an epoxy compound (D). It discloses that the polycarbonate resin composition contains specific amounts of components (A) to (D), and thereby exhibits good hue and brightness even when molded at high temperatures, and also has excellent hydrolysis resistance.

[0004] International Publication No. 2017 / 212512

[0005] In recent years, there has been a trend toward higher output and longer LEDs as light sources for DRLs to improve vehicle visibility. There is a demand for the development of resin compositions that are less susceptible to deterioration due to light or the heat caused by irradiation with high-output LED light and that exhibit minimal change in the color tone of guided light over long light guide paths.

[0006] On the other hand, Patent Document 1 does not disclose any change in color tone of guided light in a long light guide path, long-term heat resistance, or long-term moist heat resistance of the molded article molded from the polycarbonate resin composition for optical parts.

[0007] An object of one aspect of the present invention is to provide a polycarbonate resin composition capable of producing a molded article that exhibits little change in color tone of guided light over a long light guide path and has excellent long-term heat resistance and long-term moist heat resistance.

[0008] As a result of intensive investigations aimed at solving the above-mentioned problems, the present inventors have found that the above-mentioned problems can be solved by a polycarbonate resin composition in which a polycarbonate resin is blended with an alicyclic epoxy compound and a phosphorus-based antioxidant having a specific structure in specific amounts, and have thus completed the present invention.

[0009] A polycarbonate resin composition according to one aspect of the present invention comprises a polycarbonate resin, a phosphorus-based antioxidant, and an alicyclic epoxy compound, wherein the phosphorus-based antioxidant comprises a pentaerythritol diphosphite compound represented by the following general formula (1), the content of the alicyclic epoxy compound is 0.01 parts by mass or more and 0.6 parts by mass or less relative to 100 parts by mass of the polycarbonate resin, the content of the pentaerythritol diphosphite compound is 0.01 parts by mass or more and 0.35 parts by mass or less relative to 100 parts by mass of the polycarbonate resin, the content of the phosphorus-based antioxidant is 0.2 parts by mass or more relative to 100 parts by mass of the polycarbonate resin, and a ratio of the content of the alicyclic epoxy compound to the content of the pentaerythritol diphosphite compound is 0.7 or more: In formula (1), R Ｃ１１ ~R Ｃ１６ are (i) a hydrogen atom or an aromatic ring-containing group having 6 to 15 carbon atoms, which may be the same or different, or (ii) a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, which may be the same or different, with the proviso that R Ｃ１１ ~R Ｃ１６ Not all of them will be hydrogen atoms.

[0010] According to one aspect of the present invention, it is possible to provide a polycarbonate resin composition capable of producing a molded article that exhibits little change in color tone of guided light over a long light guide path and has excellent long-term heat resistance and long-term moist heat resistance.

[0011] One embodiment of the present invention will be described in detail below. In this specification, unless otherwise specified, the expression "A to B" representing a range of numerical values ​​means "A or more and B or less."

[0012] 1. Polycarbonate Resin Composition A polycarbonate resin composition according to one aspect of the present invention (hereinafter sometimes simply referred to as "resin composition") comprises a polycarbonate resin, a phosphorus-based antioxidant, and an alicyclic epoxy compound. The resin composition according to one aspect of the present invention includes a blend obtained by blending raw materials for the resin composition including the aforementioned components, and a kneaded product obtained by melt-kneading the blend.

[0013] [Polycarbonate Resin] The type of polycarbonate resin is not particularly limited as long as it is a resin containing a polymer having a carbonate bond (—O—CO—O—) in the main chain. The polycarbonate resin may be, for example, an aromatic polycarbonate resin or an aliphatic polycarbonate. The aromatic polycarbonate resin is a polycarbonate resin containing an aromatic ring such as a benzene ring between carbonate bonds in the main chain, and the aliphatic polycarbonate resin is a polycarbonate resin not containing an aromatic ring such as a benzene ring between carbonate bonds in the main chain. The polycarbonate resin may also have a branched structure. One type of polycarbonate resin may be used alone, or two or more types may be used in combination in any ratio.

[0014] The polycarbonate resin may be produced by a known method. For example, a polycarbonate resin produced by reacting a dihydric phenol with a carbonate precursor by a solution method (interfacial polycondensation method) or a melt method (ester interchange method), i.e., an interfacial polycondensation method in which a dihydric phenol is reacted with phosgene in the presence of a terminal terminator, or a polycarbonate resin produced by reacting a dihydric phenol with diphenyl carbonate or the like in the presence of a terminal terminator by an ester interchange method, may be used as the polycarbonate resin.

[0015] The dihydric phenol, carbonate precursor, end-capping agent, etc. that can be used in the production of polycarbonate resins may be those commonly used in the art. For example, the dihydric phenol, carbonate precursor, end-capping agent, etc. disclosed in WO 2018 / 181949 can be used in the production of polycarbonate resins.

[0016] In one aspect of the present invention, the viscosity average molecular weight (Mv) of the polycarbonate resin is not limited, but from the viewpoint of flowability, it is preferably 10,000 or more and 30,000 or less, more preferably 11,000 or more and 26,000 or less. In particular, when the resin composition according to one aspect of the present invention is used in a light-guiding component (e.g., a DRL), the Mv of the polycarbonate resin is preferably 12,000 or more and 25,000 or less, and more preferably 13,000 or more and 23,000 or less.

[0017] In this specification, the viscosity average molecular weight (Mv) is calculated by measuring the viscosity of a methylene chloride solution at 20°C using an Ubbelohde viscometer, determining the intrinsic viscosity [η] from the viscosity, and then calculating it using the following formula: [η] = 1.23 × 10-5 Mv ０．８３

[0018] (Preferred Types of Polycarbonate Resins)

[0019] The polycarbonate resin preferably contains an aromatic polycarbonate resin whose main chain has a repeating unit represented by the following general formula (I). (In the formula (I), R Ａ１ and R Ａ２ is an alkyl or alkoxy group having 1 to 6 carbon atoms, and R Ａ１ and R Ａ２ and may be the same or different; X represents a single bond, an alkylene group having 1 to 8 carbon atoms, an alkylidene group having 2 to 8 carbon atoms, a cycloalkylene group having 5 to 15 carbon atoms, a cycloalkylidene group having 5 to 15 carbon atoms, -S-, -SO-, -SO ２ a and b each independently represent an integer of 0 to 4; when a is 2 or more, RＡ１ may be the same or different, and when b is 2 or more, R Ａ２ may be the same or different.)

[0020] R Ａ１ and R Ａ２ Examples of alkyl groups represented by R include methyl, ethyl, n-propyl, isopropyl, various butyl groups (the term "various" refers to both linear and branched groups, and the same applies hereinafter), various pentyl groups, and various hexyl groups. Ａ１ and R Ａ２ Examples of the alkoxy group represented by the formula (I) include an alkoxy group in which the alkyl group moiety is one of the alkyl groups exemplified above. Ａ１ and R Ａ２ is preferably an alkyl group having 1 to 4 carbon atoms or an alkoxy group having 1 to 4 carbon atoms.

[0021] Examples of the alkylene group represented by X include a methylene group, an ethylene group, a trimethylene group, a tetramethylene group, and a hexamethylene group, and alkylene groups having 1 to 5 carbon atoms are preferred. Examples of the alkylidene group represented by X include an ethylidene group and an isopropylidene group. Examples of the cycloalkylene group represented by X include a cyclopentanediyl group, a cyclohexanediyl group, and a cyclooctanediyl group, and cycloalkylene groups having 5 to 10 carbon atoms are preferred. Examples of the cycloalkylidene group represented by X include a cyclohexylidene group, a 3,5,5-trimethylcyclohexylidene group, and a 2-adamantylidene group, and cycloalkylidene groups having 5 to 10 carbon atoms are preferred, and cycloalkylidene groups having 5 to 8 carbon atoms are more preferred.

[0022] a and b each independently represent an integer of 0 or more and 4 or less, preferably 0 or more and 2 or less, and more preferably 0 or 1.

[0023] Examples of aromatic polycarbonate resins having a main chain with a repeating unit represented by the following general formula (I) include aromatic polycarbonate resins having a bisphenol A structure (in the general formula (I) above, X is an isopropylidene group).

[0024] Specific examples of aromatic polycarbonate resins having a bisphenol A structure include Toughlon. ＴＭ (manufactured by FORMOSA IDEMITSU PETROCHEMICAL CORP.) and the like.

[0025] In one embodiment of the present invention, the aromatic polycarbonate resin preferably contains an aromatic polycarbonate resin having a bisphenol A structure, from the viewpoints of the transparency, mechanical properties, thermal properties, etc. of the resulting molded article.

[0026] The content of the aromatic polycarbonate resin having a bisphenol A structure in the aromatic polycarbonate resin is not limited, but since the expected effects of including the aromatic polycarbonate resin having a bisphenol A structure can be fully obtained, the content is preferably 50% by mass or more and 100% by mass or less, more preferably 75% by mass or more and 100% by mass or less, even more preferably 85% by mass or more and 100% by mass or less, and even more preferably 95% by mass or more and 100% by mass or less.

[0027] [Phosphorus-Based Antioxidant] The phosphorus-based antioxidant includes a pentaerythritol diphosphite compound represented by the following general formula (1). In formula (1), R Ｃ１１ ~R Ｃ１６ are (i) a hydrogen atom or an aromatic ring-containing group having 6 to 15 carbon atoms, which may be the same or different, or (ii) a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, which may be the same or different, with the proviso that R Ｃ１１ ~R Ｃ１６ Not all of them will be hydrogen atoms.

[0028] R in formula (1) Ｃ１１ ~R Ｃ１６ is preferably the above (i).Ｃ１１ ~R Ｃ１６ When (i) is satisfied, examples of the aromatic ring-containing group having 6 to 15 carbon atoms include a phenyl group, a tolyl group, a xylyl group, a naphthyl group, a biphenyl group, a benzyl group, a phenethyl group, a phenylpropyl group, a cumyl group, etc. These groups may further have a substituent such as a hydroxyl group or an amino group.

[0029] Furthermore, R in formula (1) Ｃ１１ ~R Ｃ１６ When (ii) is satisfied, examples of the alkyl group having 1 to 12 carbon atoms include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, various butyl groups, various pentyl groups, various hexyl groups, various octyl groups, various nonyl groups, various decyl groups, various undecyl groups, and various dodecyl groups.

[0030] Specific examples of the compound represented by the formula (1) include bis(2,4-dicumylphenyl)pentaerythritol diphosphite, bis(2,6-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphite, and the like.

[0031] (Preferred examples of compounds represented by formula (1)) R in the formula (1) Ｃ１１ ~R Ｃ１６ In the case of (i), the number of carbon atoms in the aromatic ring-containing group is preferably 6 or more and 13 or less, more preferably 6 or more and 10 or less. Examples of the aromatic ring include a benzene ring, a naphthalene ring, a phenanthrene ring, and an anthracene ring, and a benzene ring is preferred.

[0032] Among these, the aromatic ring-containing group having 6 to 15 carbon atoms is preferably a group represented by the following general formula (1a). In formula (1a), R Ｃ１７ , R Ｃ１８ are alkyl or alkenyl groups, which may be the same or different. Alternatively, R Ｃ１７ and R Ｃ１８ may be bonded to each other to form a ring. Ｃ１７ , R Ｃ１８is preferably an alkyl group having 1 to 5 carbon atoms or an alkenyl group having 2 to 5 carbon atoms, more preferably an alkyl group having 1 to 3 carbon atoms, and even more preferably a methyl group.

[0033] In formula (1a), R Ｃ１９ is a hydrogen atom or an alkyl group, preferably a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, more preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and even more preferably a hydrogen atom. m is an integer of 0 to 5. When m is 2 or more, multiple R Ｃ１９ may be the same or different.

[0034] In formula (1a), Z represents a single bond or a carbon atom. When Z is a single bond, R Ｃ１７ , R Ｃ１８ is excluded from general formula (1a).

[0035] When the compound represented by the formula (1) has two or more groups represented by the general formula (1a), the multiple groups may be the same or different from each other.

[0036] The compound represented by formula (1) is a compound represented by formula (1), wherein R Ｃ１１ and R Ｃ１４ is a hydrogen atom, and R Ｃ１２ ~R Ｃ１３ , R Ｃ１５ ~R Ｃ１６ is preferably an aromatic ring-containing group having 6 to 15 carbon atoms, and R Ｃ１１ and R Ｃ１４ is a hydrogen atom, and R Ｃ１２ ~R Ｃ１３ , R Ｃ１５ ~R Ｃ１６ is more preferably a group represented by the general formula (1a).

[0037] That is, the compound represented by the formula (1) is preferably a pentaerythritol diphosphite compound represented by the following general formula (1-1): In the formula, R Ｃ１７ａ ~R Ｃ１７ｄ , R Ｃ１８ａ ~R Ｃ１８ｄare alkyl or alkenyl groups, which may be the same or different. Alternatively, R Ｃ１７ａ and R Ｃ１８ａ , R Ｃ１７ｂ and R Ｃ１８ｂ , R Ｃ１７ｃ and R Ｃ１８ｃ , R Ｃ１７ｄ and R Ｃ１８ｄ may be bonded to each other to form a ring.

[0038] R Ｃ１９ａ ~R Ｃ１９ｄ are hydrogen atoms or alkyl groups, and may be the same or different.

[0039] m1 to m4 are integers of 0 to 5, and may be the same or different. When m1 to m4 are 2 or more, multiple R Ｃ１９ａ , R Ｃ１９ｂ , R Ｃ１９ｃ , R Ｃ１９ｄ may be the same or different.

[0040] Z １ ~Z ４ represents a single bond or a carbon atom, and may be the same or different. １ ~Z ４ When represents a single bond, R Ｃ１７ａ ~R Ｃ１７ｄ , R Ｃ１８ａ ~R Ｃ１８ｄ is excluded from the general formula (1-1).

[0041] In general formula (1-1), R Ｃ１７ａ ~R Ｃ１７ｄ , R Ｃ１８ａ ~R Ｃ１８ｄ is preferably an alkyl group having 1 to 5 carbon atoms or an alkenyl group having 2 to 5 carbon atoms, more preferably an alkyl group having 1 to 3 carbon atoms, and even more preferably a methyl group. Ｃ１７ａ ~R Ｃ１７ｄ and R Ｃ１８ａ ~R Ｃ１８ｄ It is even more preferred that all of are methyl groups.

[0042] R Ｃ１９ａ ~R Ｃ１９ｄis preferably a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, more preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and even more preferably a hydrogen atom; R Ｃ１９ａ ~R Ｃ１９ｄ It is even more preferable that all of are hydrogen atoms.

[0043] m1 to m4 are preferably integers of 0 or more and 3 or less, more preferably integers of 0 or more and 1 or less, and even more preferably 0. Z １ ~Z ４ is preferably a carbon atom.

[0044] Among the pentaerythritol diphosphite compounds represented by the general formula (1-1), bis(2,4-dicumylphenyl)pentaerythritol diphosphite represented by the following formula (1-2) is particularly suitable. Bis(2,4-dicumylphenyl)pentaerythritol diphosphite is available as a commercially available product, and for example, "Doverphos S-9228PC" manufactured by Dover Chemical Company can be used.

[0045]

[0046] In addition, R in the formula (1) Ｃ１１ ~R Ｃ１６ is (ii) above, in formula (1), R Ｃ１１ ~R Ｃ１６ Each of R is preferably an alkyl group having 1 to 12 carbon atoms. Ｃ１１ ~R Ｃ１６ is more preferably one or more selected from the group consisting of a methyl group, an ethyl group, an n-propyl group, an isopropyl group, various butyl groups, various pentyl groups, various hexyl groups, and various octyl groups, and even more preferably one or more selected from the group consisting of a methyl group, an ethyl group, an isopropyl group, and a tert-butyl group.

[0047] Among them, the compound represented by the formula (1) is R Ｃ１１ , R Ｃ１３ , R Ｃ１４ and R Ｃ１６ is a tert-butyl group, and R Ｃ１２ and RＣ１５ is a methyl group. That is, the compound represented by formula (1) is preferably bis(2,6-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphite represented by the following formula (1-3). Bis(2,6-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphite is available as a commercially available product, and for example, "ADEKA STAB PEP-36" manufactured by ADEKA Corporation can be used.

[0048]

[0049] (Pentaerythritol diphosphite compound content) The resin composition according to one embodiment of the present invention contains 0.01 parts by mass or more and 0.35 parts by mass or less of a pentaerythritol diphosphite compound per 100 parts by mass of a polycarbonate resin. When the content of the pentaerythritol diphosphite compound in the resin composition is within the above-described range, a molded article containing the resin composition exhibits little change in the color tone of guided light in a long light guide path, and has improved long-term heat resistance.

[0050] In order to further reduce the change in color tone of guided light in the long light guide path of a molded article containing the resin composition, the content of the pentaerythritol diphosphite compound in the resin composition according to one embodiment of the present invention is preferably 0.05 parts by mass or more, more preferably 0.07 parts by mass or more, and even more preferably 0.1 parts by mass or more, relative to 100 parts by mass of polycarbonate resin. Furthermore, in order to further improve the long-term heat resistance of a molded article containing the resin composition, the content of the pentaerythritol diphosphite compound in the resin composition according to one embodiment of the present invention is preferably 0.3 parts by mass or less, more preferably 0.25 parts by mass or less, relative to 100 parts by mass of polycarbonate resin.

[0051] The phosphorus-based antioxidant may be a pentaerythritol diphosphite compound represented by the general formula (1) alone or in combination of two or more kinds. Examples of phosphorus-based antioxidants other than the pentaerythritol diphosphite compound represented by the general formula (1) include aryl phosphite compounds and aryl phosphine compounds.

[0052] (Aryl Phosphite Compound) The aryl phosphite compound is not particularly limited, and examples thereof include compounds represented by the following general formula (2).

[0053] In formula (2), R Ｃ２１ ~R Ｃ２５ are hydrogen atoms, alkyl groups having 1 to 12 carbon atoms, or aryl groups having 6 to 14 carbon atoms, and may be the same or different. However, from the viewpoint of the effect as an antioxidant, R Ｃ２１ ~R Ｃ２５ cannot all be hydrogen atoms, and R Ｃ２１ ~R Ｃ２５ At least two of the groups are alkyl groups having 1 to 12 carbon atoms or aryl groups having 6 to 14 carbon atoms.

[0054] Specific examples of the compound represented by the formula (2) include tris(2,4-di-tert-butylphenyl)phosphite.

[0055] (Preferred examples of compounds represented by formula (2)) In the formula (2), R Ｃ２１ ~R Ｃ２５ and R are preferably compounds in which any two of them are alkyl groups having 1 to 12 carbon atoms or aryl groups having 6 to 14 carbon atoms, and the remaining are hydrogen atoms; Ｃ２１ ~R Ｃ２５ Among compounds in which any two of the groups are alkyl groups having 1 to 12 carbon atoms or aryl groups having 6 to 14 carbon atoms, and the remaining groups are hydrogen atoms, R Ｃ２１ or R Ｃ２５ More preferred are compounds in which at least one of the groups is an alkyl group having 1 to 12 carbon atoms or an aryl group having 6 to 14 carbon atoms.

[0056] Examples of alkyl groups having 1 to 12 carbon atoms include methyl, ethyl, n-propyl, isopropyl, various butyl groups, various pentyl groups, various hexyl groups, various octyl groups, various decyl groups, various dodecyl groups, etc. Among these, one or more selected from the group consisting of methyl, ethyl, n-propyl, isopropyl, various butyl groups, various pentyl groups, various hexyl groups, and various octyl groups is preferred, one or more selected from the group consisting of methyl, ethyl, isopropyl, and tert-butyl groups is more preferred, and tert-butyl groups is even more preferred.

[0057] Examples of the aryl group having 6 to 14 carbon atoms include a phenyl group, a tolyl group, and a xylyl group.

[0058] Among them, R Ｃ２１ ~R Ｃ２５ is more preferably a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, further preferably a hydrogen atom, a methyl group, an ethyl group, an isopropyl group, or a tert-butyl group, and even more preferably a hydrogen atom or a tert-butyl group. Particularly preferred compounds represented by the formula (2) include Ｃ２１ and R Ｃ２３ is a tert-butyl group, and R Ｃ２２ , R Ｃ２４ and R Ｃ２５ is a hydrogen atom, for example, tris(2,4-di-tert-butylphenyl)phosphite represented by the following formula (2-1): Tris(2,4-di-tert-butylphenyl)phosphite is commercially available, and for example, "IRGAFOS168" manufactured by BASF can be used.

[0059]

[0060] (Examples other than compounds represented by formula (2)) Other examples of the aryl phosphite compound include compounds represented by the following general formula (4) and compounds represented by the following general formula (5).

[0061] The compound represented by formula (4) is 2,2'-methylenebis(4,6-di-tert-butylphenyl)2-ethylhexyl phosphite. 2,2'-methylenebis(4,6-di-tert-butylphenyl)2-ethylhexyl phosphite is commercially available, and for example, "ADEKATAB HP-10" manufactured by ADEKA Corporation can be used.

[0062] The compound represented by formula (5) is 2-tert-butyl-6-methyl-4-{3-[2,4,8,10-tetra-tert-butyldibenzo[d,f][1,3,2]dioxaphosphepin-6-yl)oxy]propyl}phenol. 2-tert-butyl-6-methyl-4-{3-[2,4,8,10-tetra-tert-butyldibenzo[d,f][1,3,2]dioxaphosphepin-6-yl)oxy]propyl}phenol is commercially available, and for example, "Sumilizer GP" manufactured by Sumitomo Chemical Co., Ltd. can be used.

[0063] (Aryl Phosphine Compound) The aryl phosphine compound may be any phosphine compound having one or more aryl groups, and examples thereof include compounds represented by the following general formula (3): P-(R Ｄ２１ ) ３ (3) In the formula (3), R Ｄ２１ is a hydrocarbon group which may have a substituent, and at least one of them is an aryl group having 6 to 18 carbon atoms. Ｄ２１ may be the same or different.

[0064] Examples of the compound represented by general formula (3) include triphenylphosphine, diphenylbutylphosphine, diphenyloctadecylphosphine, tris(p-tolyl)phosphine, tris(p-nonylphenyl)phosphine, tris(naphthyl)phosphine, diphenyl(hydroxymethyl)phosphine, diphenyl(acetoxymethyl)phosphine, diphenyl(β-ethylcarboxyethyl)phosphine, tris(p-chlorophenyl)phosphine, tris(p-fluorophenyl)phosphine, diphenylbenzylphosphine, diphenyl-β-cyanoethylphosphine, diphenyl(p-hydroxyphenyl)phosphine, diphenyl-1,4-dihydroxyphenyl-2-phosphine, and phenylnaphthylbenzylphosphine.

[0065] (Preferred examples of the compound represented by formula (3)) Among them, R Ｄ２１ are preferably aryl groups, and triphenylphosphine is more preferred. Triphenylphosphine is commercially available, for example, "JC-263" manufactured by Johoku Chemical Industry Co., Ltd.

[0066] (Total Content of Phosphorus-Based Antioxidants) The resin composition according to one embodiment of the present invention contains a total of 0.2 parts by mass or more of phosphorus-based antioxidants per 100 parts by mass of polycarbonate resin. When the total content of the phosphorus-based antioxidants in the resin composition is within the above-mentioned range, a molded article containing the resin composition exhibits less change in color tone of guided light in a long light guide path, and has improved long-term heat resistance and long-term moist heat resistance.

[0067] The total content of the phosphorus-based antioxidants in the resin composition according to one embodiment of the present invention is preferably 0.25 parts by mass or more, and more preferably 0.3 parts by mass or more, per 100 parts by mass of polycarbonate resin, in order to reduce the color change of light guided through a long light guide path and the initial color change after molding in a molded article containing the resin composition. Furthermore, the total content of the phosphorus-based antioxidants in the resin composition according to one embodiment of the present invention is preferably 0.6 parts by mass or less, and more preferably 0.55 parts by mass or less, per 100 parts by mass of polycarbonate resin, in order to improve the long-term heat resistance of a molded article containing the resin composition at 140°C and 120°C in a balanced manner.

[0068] [Alicyclic Epoxy Compound] The alicyclic epoxy compound refers to a cyclic aliphatic compound having an alicyclic epoxy group, i.e., an epoxy group in which one oxygen atom is added to an ethylene bond in an aliphatic ring. The type of the alicyclic epoxy compound is not particularly limited and can be appropriately selected.

[0069] Examples of alicyclic epoxy compounds include (i) compounds having an alicyclic epoxy group in the molecule, and (ii) compounds in which an epoxy group is directly bonded to an alicyclic ring via a single bond. Here, the "alicyclic epoxy group" refers to an epoxy group composed of two adjacent carbon atoms and an oxygen atom that constitute an alicyclic ring. Examples of the "compound having an alicyclic epoxy group in the molecule" include compounds having a cyclopentene oxide group and compounds having a cyclohexene oxide group.

[0070] As the alicyclic epoxy compound, for example, alicyclic epoxy compounds represented by the following formulas (B-1) to (B-10) are preferably used.

[0071] (Wherein R is H or CH ３ It is.) (Wherein R is H or CH ３ It is.) (Wherein, a+b=1 or 2.) (Wherein, a+b+c+d=1, 2, or 3.) (wherein a+b+c=n (an integer), and R is a hydrocarbon group.) (wherein n is an integer.) (wherein R is a hydrocarbon group). (wherein n is an integer and R is a hydrocarbon group.)

[0072] The alicyclic epoxy compounds represented by the formulae (B-1) to (B-6) and (B-8) are examples of the "compounds having a cyclohexene oxide group". The alicyclic epoxy compounds represented by the formulae (B-7), (B-9) and (B-10) are examples of the "compounds in which an epoxy group is directly bonded to an alicyclic ring via a single bond".

[0073] The alicyclic epoxy compounds may be used alone or in combination of two or more kinds in any ratio.

[0074] (Preferred Types of Alicyclic Epoxy Compounds) In terms of excellent compatibility with polycarbonate resins and not impairing transparency, the alicyclic epoxy compound is preferably one or more selected from the group consisting of compounds represented by formula (B-1) and formula (B-10), and more preferably a compound represented by formula (B-1).

[0075] For example, the compound represented by formula (B-1) is 3',4'-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, which is commercially available under the product name "Celloxide 2021P" (manufactured by Daicel Corporation).

[0076] Furthermore, an example of the compound represented by formula (B-10) is a 1,2-epoxy-4-(2-oxiranyl)cyclohexane adduct of 2,2-bis(hydroxymethyl)-1-butanol, which is commercially available under the product name "EHPE3150" (manufactured by Daicel Corporation).

[0077] Furthermore, a mixture of Celloxide 2021P and EHPE3150, commercially available from Daicel Corporation under the product name "EHPE3150CE", can also be preferably used.

[0078] Therefore, the alicyclic epoxy compound preferably includes 3',4'-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate.

[0079] In addition to the alicyclic epoxy compounds exemplified above, bi-7-oxabicyclo[4.1.0]heptane can also be preferably used. Bi-7-oxabicyclo[4.1.0]heptane is commercially available under the product name "Celloxide 8010" (manufactured by Daicel Corporation).

[0080] (Alicyclic Epoxy Compound Content) The resin composition according to one embodiment of the present invention contains 0.01 parts by mass or more and 0.6 parts by mass or less of an alicyclic epoxy compound per 100 parts by mass of a polycarbonate resin. When the content of the alicyclic epoxy compound in the resin composition is within the above-mentioned range, a molded article containing the resin composition exhibits less color change due to a long light guide path, and has improved long-term heat resistance and long-term moist heat resistance.

[0081] The content of the alicyclic epoxy compound in the resin composition according to one embodiment of the present invention is preferably 0.05 parts by mass or more, more preferably 0.1 parts by mass or more, even more preferably 0.2 parts by mass or more, even more preferably more than 0.2 parts by mass, and even more preferably 0.25 parts by mass or more, relative to 100 parts by mass of polycarbonate resin, in order to reduce color change in the light-guiding path of a molded article containing the resin composition and to improve long-term heat resistance and long-term moist heat resistance. Furthermore, the content of the alicyclic epoxy compound in the resin composition according to one embodiment of the present invention is preferably 0.55 parts by mass or less, more preferably 0.5 parts by mass or less, and even more preferably 0.45 parts by mass or less, relative to 100 parts by mass of polycarbonate resin.

[0082] (Ratio of the content of the alicyclic epoxy compound to the content of the pentaerythritol diphosphite compound) In a resin composition according to one embodiment of the present invention, the ratio of the content of the alicyclic epoxy compound to the content of the pentaerythritol diphosphite compound is 0.5 or more. When the ratio of the content of the alicyclic epoxy compound to the content of the pentaerythritol diphosphite compound is within the above-described range, a molded article containing the resin composition exhibits less change in color tone of guided light in a long light guide path, and has improved long-term heat resistance and long-term moist heat resistance.

[0083] In a molded article containing the resin composition, the ratio of the content of the alicyclic epoxy compound to the content of the pentaerythritol diphosphite compound in the resin composition according to one aspect of the present invention is preferably 0.7 or more, more preferably 1.0 or more, even more preferably 1.5 or more, and even more preferably 2.0 or more, in terms of reducing the change in color tone of guided light in a long light guide path and further improving the long-term heat resistance and long-term moist heat resistance.

[0084] Furthermore, in the resin composition according to one aspect of the present invention, the ratio of the content of the alicyclic epoxy compound to the content of the pentaerythritol diphosphite compound is preferably 50 or less, more preferably 10 or less, and even more preferably 5.0 or less.

[0085] [Other Components] In addition to the above-described components, the resin composition according to one embodiment of the present invention can contain any additives such as fatty acid esters, polyorganosiloxanes, polyether compounds, etc., within the range that does not impair the effects of the present invention. As the additives, general additives commonly used in the art can be used.

[0086] The resin composition according to one aspect of the present invention may further contain a fatty acid ester, which is a condensation product of an aliphatic carboxylic acid and an alcohol, from the viewpoint of improving the releasability and long-term heat resistance of the resulting molded article.

[0087] Examples of the fatty acid esters include behenyl behenate, octyldodecyl behenate, stearyl stearate, glycerin monopalmitate, glycerin monostearate, glycerin monooleate, glycerin distearate, glycerin tristearate, pentaerythritol monopalmitate, pentaerythritol monostearate, pentaerythritol distearate, pentaerythritol tristearate, and pentaerythritol tetrastearate. These may be used alone or in combination of two or more. Among these, stearic acid esters are preferred as fatty acid esters, and glycerin monostearate is more preferred. Glycerin monostearate is commercially available; for example, "S-100A" manufactured by Riken Vitamin Co., Ltd. may be used.

[0088] When the resin composition contains a fatty acid ester, the content of the fatty acid ester in the resin composition is preferably 0.01 parts by mass or more, more preferably 0.02 parts by mass or more, and even more preferably 0.03 parts by mass or more, per 100 parts by mass of the aromatic polycarbonate resin, in order to improve releasability. Furthermore, the content of the fatty acid ester in the resin composition is preferably 0.2 parts by mass or less, more preferably 0.1 parts by mass or less, per 100 parts by mass of the aromatic polycarbonate resin, in order to further improve long-term heat resistance.

[0089] The polyorganosiloxane is preferably a compound having one or more functional groups such as an alkoxy group, an aryloxy group, a polyoxyalkylene group, a carboxyl group, a silanol group, an amino group, a mercapto group, an epoxy group, and a vinyl group.

[0090] The kinematic viscosity of the polyorganosiloxane is preferably 10 mm at 25°C from the viewpoint of the lubrication effect as a mold release property. ２ / s or more, and from the viewpoint of dispersibility in polycarbonate resin, it is preferably 200 mm ２ From this viewpoint, the viscosity of the polyorganosiloxane is more preferably 20 mm ２ / s or more 150mm ２ / s or less, more preferably 40 mm ２ / s or more 120mm ２ / s or less.

[0091] The refractive index of the polyorganosiloxane is preferably as small as possible so as not to reduce the transparency when added to polycarbonate. Since the refractive index of polycarbonate is 1.58, the refractive index of the polyorganosiloxane is preferably 1.45 or more, more preferably 1.50 or more.

[0092] The amount of polyorganosiloxane added is preferably 0.01 to 0.15 parts by mass, more preferably 0.02 to 0.15 parts by mass, and even more preferably 0.05 to 0.1 parts by mass, relative to 100 parts by mass of the aromatic polycarbonate resin (A). Within this range, mold releasability can be improved, and mold deposits can be significantly reduced even under continuous molding conditions.

[0093] Specific examples of the polyether compound include polyoxyethylene glycol-polyoxypropylene glycol, polyoxyethylene glycol-polyoxytetramethylene glycol, polyoxytrimethylene glycol-polyoxytetramethylene glycol, polyoxypropylene glycol-polyoxytetramethylene glycol, polyoxyethylene-polyoxypropylene-bisphenol A ether, and polyethylene glycol-polypropylene glycol-allyl ether. Among these, one or more selected from the group consisting of polyoxyethylene glycol-polyoxypropylene glycol, polyoxyethylene glycol-polyoxytetramethylene glycol, polyoxytrimethylene glycol-polyoxytetramethylene glycol, and polyoxypropylene glycol-polyoxytetramethylene glycol are preferred, one or more selected from the group consisting of polyoxyethylene glycol-polyoxypropylene glycol, polyoxyethylene glycol-polyoxytetramethylene glycol, and polyoxypropylene glycol-polyoxytetramethylene glycol are more preferred, and one or more selected from the group consisting of polyoxyethylene glycol-polyoxytetramethylene glycol and polyoxypropylene glycol-polyoxytetramethylene glycol are even more preferred.

[0094] The molecular weight of the polyether compound is preferably in the range of 200 to 10,000, more preferably 500 to 8,000, even more preferably 800 to 5,000, and still more preferably 1,000 to 4,000, in terms of weight average molecular weight (Mw).

[0095] From the viewpoint of obtaining the effects of the present invention, the content of the polyether compound in the resin composition according to one embodiment of the present invention is preferably 0.1 to 2.0 parts by mass, more preferably 0.2 to 2.0 parts by mass, and even more preferably 0.5 to 2.0 parts by mass, relative to 100 parts by mass of the polycarbonate resin. When the content of the polyether compound is 0.1 part by mass or more relative to 100 parts by mass of the polycarbonate resin, an increase in the YI value is suppressed and the color tone is improved. Furthermore, when the content is 2.0 parts by mass or less, the transmittance is improved.

[0096] The resin composition according to one aspect of the present invention preferably does not contain a polyether compound, in terms of the long-term moist heat resistance of a molded article containing the resin composition.

[0097] [Method for Producing Polycarbonate Resin Composition] There are no particular limitations on the method for producing the resin composition according to one embodiment of the present invention, and the resin composition can be produced by a known method. For example, the resin composition can be produced by mixing the above-mentioned components at room temperature (e.g., 20°C to 30°C) and melt-kneading the mixture. The melt-kneading can be carried out by a method commonly used in the art, such as a method using a single-screw extruder, a twin-screw extruder, a co-kneader, or a multi-screw extruder. The heating temperature during melt-kneading is usually selected appropriately from the range of 220°C or higher and 300°C or lower.

[0098] [Characteristics of Polycarbonate Resin Composition] When a molded article for optical property measurement made of the resin composition is used and colorimetric measurement is performed using a white light-emitting diode as a light source, the molded article for optical property measurement preferably has a y value of 0.41 or less in the CIE 1931 color system at a position 1005 mm from the incident portion of the light guide path. Since the y value is 0.41 or less, a molded article containing the resin composition exhibits little change in color tone of guided light in a long light guide path, making the resin composition suitable for use in light guide parts for vehicles, etc.

[0099] The molded body for measuring optical properties comprises an incident portion where light is incident, an exit portion where the incident light exits, and a light guide portion that guides the incident light from the incident portion to the exit portion, and the light guide portion has an optical path with a curvature that causes total reflection of the incident light.

[0100] The manufacturing conditions for the molded article for measuring optical properties are a cylinder temperature of 300° C., a mold temperature of 80° C., and a cycle time of 40 seconds. Specifically, the molded article for measuring optical properties is obtained by the method described in the examples below.

[0101] The y value is more preferably 0.405 or less, and even more preferably 0.40 or less, in order to reduce the change in color tone of guided light in the long light guide path of a molded article containing the resin composition.

[0102] The resin composition according to one embodiment of the present invention is prepared by injection molding the polycarbonate resin composition under the conditions of a cylinder temperature of 260°C, a mold temperature of 80°C, and a cycle time of 50 seconds. The molded article having a thickness of 5 mm is stored at 140°C for 1,000 hours, and then the YI value (YI １ ) is preferably 2.0 or less. １ If the modulus is 2.0 or less, the molded article containing the resin composition has good long-term heat resistance and is suitable for light guide parts and the like.

[0103] YI is preferred in that the long-term heat resistance of a molded article containing the resin composition is better. １ is more preferably 1.9 or less, and even more preferably 1.8 or less.

[0104] The resin composition according to one aspect of the present invention has good long-term heat resistance, and the resin composition according to one aspect of the present invention has a YI value (YI) of 5 mm thick molded articles produced by injection molding using the polycarbonate resin composition under production conditions of a cylinder temperature of 260°C, a mold temperature of 80°C, and a cycle time of 50 seconds. The YI value (YI) is measured using a spectrophotometer under conditions of a C light source and a 2-degree field of view after the molded articles are stored at 120°C for 1,000 hours. ２ ) is preferably 2.0 or less, more preferably 1.9 or less, and even more preferably 1.8 or less.

[0105] YI is preferred in that the long-term heat resistance of a molded article containing the resin composition according to one embodiment of the present invention is better. １ and Y.I. ２ are more preferably 2.0 or less, even more preferably 1.9 or less, and even more preferably 1.8 or less.

[0106] In terms of the long-term moist heat resistance of a molded article containing the resin composition according to one aspect of the present invention, the resin composition according to one aspect of the present invention has a good long-term moist heat resistance. When a molded article having a thickness of 5 mm is produced using the resin composition by injection molding under manufacturing conditions of a cylinder temperature of 260°C, a mold temperature of 80°C, and a cycle time of 50 seconds, and the molded article is stored for 1,000 hours in an environment of 85°C and 85% humidity, the YI value (YI ３ ) is preferably 1.2 or less, more preferably 1.1 or less.

[0107] The resin composition according to one aspect of the present invention has a small initial color change after molding of a molded article containing the resin composition according to one aspect of the present invention. The resin composition according to one aspect of the present invention has a YI value (YI ０ ) is preferably 1.2 or less, more preferably 1.1 or less, and even more preferably 1.0 or less.

[0108] YI ０ ~YI ３ The measurement can be carried out, for example, by the measurement method described in the Examples.

[0109] <2. Molded Article> A molded article containing a resin composition according to an aspect of the present invention is also included in the scope of the present invention. The resin composition according to an aspect of the present invention in the molded article according to an aspect of the present invention has already been described, so it will not be repeated here.

[0110] [Method for Producing Molded Articles] The molded article according to one embodiment of the present invention can be produced by a production method including a molding step of molding the resin composition according to one embodiment of the present invention. The method for molding the resin composition according to one embodiment of the present invention in the molding step is not particularly limited. For example, the molded article can be produced by known molding methods such as injection molding, injection compression molding, extrusion molding, blow molding, press molding, vacuum molding, and foam molding using a melt-kneaded product of the resin composition according to one embodiment of the present invention or pellets obtained through melt-kneading as a raw material. It is particularly preferable to produce a molded article by injection molding or injection compression molding using the obtained pellets. The molding temperature in the molding step is not particularly limited and can be set appropriately. For example, molding can be performed at a temperature of 240°C or higher and 300°C or lower.

[0111] The molded article according to one embodiment of the present invention exhibits little color change in the light guide path over a long light guide path and has excellent long-term heat resistance and long-term moist heat resistance. Because these properties are fully exhibited, the molded article according to one embodiment of the present invention is preferably a light guide component, more preferably a light guide component for a vehicle, and even more preferably a light guide component for a vehicle daytime running light or daytime running lamp, i.e., a vehicle DRL. The light guide path length from the incident portion to the exit portion of the light guide component may be 100 mm or more, 500 mm or more, 1000 mm or more, or 2000 mm or more. The light guide component may have a plurality of exit portions.

[0112] [Summary] A polycarbonate resin composition according to Aspect 1 of the present invention comprises a polycarbonate resin, a phosphorus-based antioxidant, and an alicyclic epoxy compound, wherein the phosphorus-based antioxidant comprises a pentaerythritol diphosphite compound represented by the following general formula (1), wherein the content of the alicyclic epoxy compound is 0.01 parts by mass or more and 0.6 parts by mass or less relative to 100 parts by mass of the polycarbonate resin, wherein the content of the pentaerythritol diphosphite compound is 0.01 parts by mass or more and 0.35 parts by mass or less relative to 100 parts by mass of the polycarbonate resin, wherein the content of the phosphorus-based antioxidant is 0.2 parts by mass or more relative to 100 parts by mass of the polycarbonate resin, and wherein the ratio of the content of the alicyclic epoxy compound to the content of the pentaerythritol diphosphite compound is 0.7 or more: In formula (1), R Ｃ１１ ~R Ｃ１６ are (i) a hydrogen atom or an aromatic ring-containing group having 6 to 15 carbon atoms, which may be the same or different, or (ii) a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, which may be the same or different, with the proviso that R Ｃ１１ ~R Ｃ１６ Not all of them will be hydrogen atoms.

[0113] In the polycarbonate resin composition according to Aspect 2 of the present invention, in Aspect 1, the content of the pentaerythritol diphosphite compound is preferably 0.05 parts by mass or more and 0.35 parts by mass or less per 100 parts by mass of the polycarbonate resin.

[0114] In the polycarbonate resin composition according to Aspect 3 of the present invention, in Aspect 1 or 2, the ratio of the content of the alicyclic epoxy compound to the content of the pentaerythritol diphosphite compound is preferably 2.0 or more.

[0115] A polycarbonate resin composition according to Aspect 4 of the present invention is preferably any one of Aspects 1 to 3 described above, wherein the polycarbonate resin composition comprises the polycarbonate resin composition and includes an incident portion into which light is incident, an exit portion from which the incident light exits, and a light guiding portion that guides the light incident from the incident portion to the exit portion, wherein the light guiding portion has an optical path with a curvature such that the incident light is totally reflected. When colorimetry is performed using a molded article for measuring optical properties having a light path with a curvature such that the incident light is totally reflected, and a white light emitting diode as a light source, the y value of the molded article for measuring optical properties in the CIE 1931 color system at a position 1005 mm from the incident portion of the light guiding path is preferably 0.41 or less.

[0116] A polycarbonate resin composition according to Aspect 5 of the present invention is preferably the polycarbonate resin composition of any one of Aspects 1 to 4, wherein a molded article having a thickness of 5 mm is produced using the polycarbonate resin composition by injection molding under production conditions of a cylinder temperature of 260°C, a mold temperature of 80°C, and a cycle time of 50 seconds, and after storing the molded article at 140°C for 1,000 hours, the YI value measured using a spectrophotometer under conditions of Illuminant C and a 2-degree field of view is 2.0 or less.

[0117] In the polycarbonate resin composition according to Aspect 6 of the present invention, in any one of Aspects 1 to 5, the polycarbonate resin preferably contains an aromatic polycarbonate resin whose main chain has a repeating unit represented by the following general formula (I): In formula (I), R Ａ１ and R Ａ２ is an alkyl or alkoxy group having 1 to 6 carbon atoms, and R Ａ１ and R Ａ２ and may be the same or different; X represents a single bond, an alkylene group having 1 to 8 carbon atoms, an alkylidene group having 2 to 8 carbon atoms, a cycloalkylene group having 5 to 15 carbon atoms, a cycloalkylidene group having 5 to 15 carbon atoms, -S-, -SO-, -SO ２ a and b each independently represent an integer of 0 to 4; when a is 2 or more, R Ａ１ may be the same or different, and when b is 2 or more, R Ａ２ may be the same or different.

[0118] A polycarbonate resin composition according to a seventh aspect of the present invention is a polycarbonate resin composition according to any one of the first to sixth aspects, wherein in formula (1), R Ｃ１１ ~R Ｃ１６ are hydrogen atoms or aromatic ring-containing groups having 6 to 15 carbon atoms, and may be the same or different, provided that R Ｃ１１ ~R Ｃ１６ It is preferred that not all of the groups are hydrogen atoms.

[0119] The polycarbonate resin composition according to Aspect 8 of the present invention is preferably the polycarbonate resin composition according to any one of Aspects 1 to 7, wherein the pentaerythritol diphosphite compound represented by Formula (1) is bis(2,4-dicumylphenyl)pentaerythritol diphosphite.

[0120] The polycarbonate resin composition according to Aspect 9 of the present invention, in any one of Aspects 1 to 8, preferably further contains at least one phosphorus-based antioxidant selected from the group consisting of aryl phosphite compounds represented by the following general formula (2) and aryl phosphine compounds represented by the following general formula (3): In formula (2), R Ｃ２１ ~R Ｃ２５ are hydrogen atoms, alkyl groups having 1 to 12 carbon atoms, or aryl groups having 6 to 14 carbon atoms, and may be the same or different, provided that R Ｃ２１ ~R Ｃ２５ cannot all be hydrogen atoms, and R Ｃ２１ ~R Ｃ２５ at least two of P-(R) are alkyl groups having 1 to 12 carbon atoms or aryl groups having 6 to 14 carbon atoms, Ｄ２１ ) ３ (3) In formula (3), R Ｄ２１ is a hydrocarbon group which may have a substituent, at least one of which is an aryl group having 6 to 18 carbon atoms, and a plurality of R Ｄ２１ may be the same or different.

[0121] A polycarbonate resin composition according to Aspect 10 of the present invention is preferably the polycarbonate resin composition according to any one of Aspects 1 to 9, wherein the alicyclic epoxy compound comprises at least one selected from the group consisting of 3',4'-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate and bi-7-oxabicyclo[4.1.0]heptane.

[0122] A molded article according to an eleventh aspect of the present invention comprises the polycarbonate resin composition according to any one of the first to tenth aspects.

[0123] A twelfth aspect of the present invention provides a molded article, which is a light-guiding component, comprising a polycarbonate resin composition, wherein the polycarbonate resin composition comprises a polycarbonate resin, a phosphorus-based antioxidant, and an alicyclic epoxy compound, wherein the phosphorus-based antioxidant comprises a pentaerythritol diphosphite compound represented by the following general formula (1), wherein the content of the alicyclic epoxy compound is 0.01 parts by mass or more and 0.6 parts by mass or less relative to 100 parts by mass of the polycarbonate resin, the content of the pentaerythritol diphosphite compound is 0.01 parts by mass or more and 0.35 parts by mass or less relative to 100 parts by mass of the polycarbonate resin, the content of the phosphorus-based antioxidant is 0.2 parts by mass or more relative to 100 parts by mass of the polycarbonate resin, and a ratio of the content of the alicyclic epoxy compound to the content of the pentaerythritol diphosphite compound is 0.5 or more: In formula (1), R Ｃ１１ ~R Ｃ１６ are (i) a hydrogen atom or an aromatic ring-containing group having 6 to 15 carbon atoms, which may be the same or different, or (ii) a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, which may be the same or different, with the proviso that R Ｃ１１ ~R Ｃ１６ Not all of them will be hydrogen atoms.

[0124] A thirteenth aspect of the present invention provides a molded article, which is a light-guiding part for a vehicle, comprising a polycarbonate resin composition, wherein the polycarbonate resin composition comprises a polycarbonate resin, a phosphorus-based antioxidant, and an alicyclic epoxy compound, wherein the phosphorus-based antioxidant comprises a pentaerythritol diphosphite compound represented by the following general formula (1), the content of the alicyclic epoxy compound is 0.01 parts by mass or more and 0.6 parts by mass or less relative to 100 parts by mass of the polycarbonate resin, the content of the pentaerythritol diphosphite compound is 0.01 parts by mass or more and 0.35 parts by mass or less relative to 100 parts by mass of the polycarbonate resin, the content of the phosphorus-based antioxidant is 0.2 parts by mass or more relative to 100 parts by mass of the polycarbonate resin, and a ratio of the content of the alicyclic epoxy compound to the content of the pentaerythritol diphosphite compound is 0.5 or more: In formula (1), R Ｃ１１ ~R Ｃ１６ are (i) a hydrogen atom or an aromatic ring-containing group having 6 to 15 carbon atoms, which may be the same or different, or (ii) a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, which may be the same or different, with the proviso that R Ｃ１１ ~R Ｃ１６ Not all of them will be hydrogen atoms.

[0125] The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. Embodiments obtained by appropriately combining the technical means disclosed in the embodiments are also included in the technical scope of the present invention.

[0126] EXAMPLES The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited to these examples.

[0127] <Raw Materials for Polycarbonate Resin Composition> The raw materials for the polycarbonate resin composition used in the examples and comparative examples are as follows.

[0128] (Polycarbonate resin) Product name: Toughlon ＴＭFN1500” (manufactured by FORMOSA IDEMITSU PETROCHEMICAL CORP., viscosity average molecular weight (Mv) = 14,400)

[0129] (Phosphorus-based antioxidant) Product name: "Doverphos S-9228PC" (manufactured by Dover Chemical Company, bis(2,4-dicumylphenyl)pentaerythritol diphosphite)

[0130] (Phosphorus-based antioxidant) Product name "IRGAFOS168" (manufactured by BASF, tris(2,4-di-tert-butylphenyl)phosphite);

[0131] (Alicyclic epoxy compound) Product name: "Celloxide 2021P" (manufactured by Daicel Corporation, 3',4'-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate)

[0132] (Other additives: fatty acid esters) Product name: "S-100A" (Glycerin monostearate, manufactured by Riken Vitamin Co., Ltd.)

[0133] (Other additives: polyorganosiloxane) Product name "KR511" (manufactured by Shin-Etsu Chemical Co., Ltd., polyorganosiloxane compound, kinematic viscosity (25°C): 90 mm ２ / s, refractive index: 1.518)

[0134] (Other additives: polyether compounds) Product name: Unilube 50DE-25R (NOF Corporation, polyoxyethylene-polyoxypropylene glycol)

[0135] [Examples 1 to 10, Comparative Examples 1 to 7] The components were blended according to the blending ratios shown in Table 1 or Table 2 to obtain polycarbonate resin compositions of Examples 1 to 10 and Comparative Examples 1 to 7. Using a vented twin-screw extruder with a screw diameter of 37 mm ("TEM37SS" manufactured by Shibaura Machine Co., Ltd.), the polycarbonate resin composition was melt-kneaded at a cylinder temperature of 240°C, and pellets were obtained by strand cutting. The obtained pellets were dried at 120°C for 5 hours, and then molded articles were produced and various evaluations were performed using the methods described below.

[0136] <Color Tone Change of Molded Article for Measuring Optical Properties> (Preparation of Molded Article for Measuring Optical Properties) The dried pellets were used in an injection molding machine (manufactured by Niigata Machine Techno Co., Ltd., "MD350S7000": screw diameter 35 mm) to obtain an Archimedes' spiral molded article for measuring optical properties, having a width of 10 mm, a thickness of 3 mm, and a length of 1100 mm.

[0137] In manufacturing the test specimens, a mold was used in which the surface of the mold part corresponding to the light guide part (the part inside the molded body through which light passes) was polished with an abrasive having a grain size of 1000 mesh and given a mirror finish.

[0138] The exit part (1005 mm) of the molded article for measuring optical properties was subjected to mold surface treatment to form a fine striped pattern (prism shape) (surface roughness Sa = 4 μm). Each test piece was injection molded for 10 or more shots under conditions of a cylinder temperature of 300°C, a mold temperature of 80°C, and a cycle time of 40 seconds, and then molded under the same conditions after the manufacturing conditions had stabilized.

[0139] The obtained test piece for measuring optical properties had a mirror-finished surface shape for the light guide portion, a striped pattern for the surface shape of the emission portion, a surface roughness of 4 μm, and a take-out position of 1005 mm.

[0140] <Measurement of light-guiding color tone> The distance between the end of the test piece at the center of the molded article for measuring optical properties and the LED was 2 mm, and an LED light source (manufactured by Nichia Corporation, "NSFW036CT") was used, set to 0.35 A x 3.5 V, 23 lumens (1 m), and irradiated from the end face of the molded article for measuring optical properties.

[0141] The luminance and chromaticity of the emitted light from the molded article for optical property measurement subjected to irradiation were measured using a spectroradiometer ("CS-2000" manufactured by Konica Minolta, Inc.). The emitted light was extracted from an extraction position 1005 mm away from the incident part and evaluated. The obtained values ​​are shown in Tables 1 and 2 as y values ​​in the CIE 1931 color system. The pass criterion for the y value is 0.41 or less.

[0142] <Initial YI value of molded article> The dried pellets were injection molded into flat plate-shaped test pieces of 50 mm x 90 mm x 5 mm thick using an injection molding machine ("ES1000" manufactured by Nissei Plastic Industrial Co., Ltd.: screw diameter 26 mm) under the production conditions of a cylinder temperature of 260°C, a mold temperature of 80°C, and a cycle time of 50 seconds. The flat plate test pieces were injection molded after 10 or more shots of injection molding were performed under the production conditions and the production conditions had stabilized. The YI value (initial YI value: YI) of the obtained test pieces was measured using a spectrophotometer ("U-4100" manufactured by Hitachi High-Tech Corporation) under conditions of a C light source and a 2-degree field of view. ０ The results are shown in Tables 1 and 2. The acceptance criteria for the initial YI value were ０ is 1.2 or less.

[0143] <Long-term heat resistance test of molded body> YI ０ After the measurement, the flat test piece was placed in a gear oven (TABAI's "GPS-222") adjusted to a temperature of 140°C or 120°C for 1,000 hours. The YI value of the test piece after the test was measured in the same manner as above. The YI value measured after storing at 140°C for 1,000 hours was calculated as the YI value. １ The YI value measured after storage at 120°C for 1,000 hours is ２ The results are shown in Tables 1 and 2. The pass criteria for the long-term heat resistance test at 140°C are YI １ The passing standard for the long-term heat resistance test at 120°C is YI １ is 2.0 or less.

[0144] <Long-term humidity and heat resistance test of molded product> YI ０ After the measurement, the flat test piece was placed in a thermo-hygrostat ("LH33-12P" manufactured by Nagano Science Co., Ltd.) set at a temperature of 85°C and a relative humidity of 85% for 1,000 hours. After the test, the YI value (YI ３ The passing standard for the long-term humidity and heat resistance test was YI ３ is 1.2 or less.

[0145]

[0146]

[0147] From Tables 1 and 2, it can be seen that the molded articles containing the resin compositions of Examples 1 to 10 have little change in color tone of guided light in a long light guide path, and are excellent in long-term heat resistance and long-term resistance to moist heat.

[0148] It was found that the molded articles containing the resin compositions of Comparative Examples 1 to 4, in which the total content of phosphorus-based antioxidants was less than 0.2 phr, had y values ​​exceeding 0.41, and the color tone of the guided light in the long light guide path changed significantly.

[0149] In addition, in Comparative Examples 5 and 6, in which the content of Doverphos S-9228PC was more than 0.35, １ was more than 2.0, and it was found that the long-term heat resistance was poor.

[0150] Molded articles containing the resin compositions of Examples 2 to 10, in which the ratio of the content of Celloxide 2021P to the content of Doverphos S-9228PC (Celloxide 2021P / Doverphos S-9228PC) was 0.7 or more, had improved long-term moist heat resistance compared to Example 1, in which the ratio was 0.5. Furthermore, a comparison of Examples 1 to 3, which did not contain a polyether compound, with Examples 7 to 10 revealed that molded articles containing the resin compositions of Examples 7 to 10, in which the ratio was 2.0 or more, showed little change in the color tone of guided light in the long light guide path, and in addition to having excellent long-term heat resistance, also had further improved long-term moist heat resistance.

[0151] Comparison between Examples 8 and 10 shows that when the total content of the phosphorus-based antioxidants is 0.45 phr or less, the long-term moist heat resistance is further improved, and the long-term heat resistance (YI) at 140°C and 120°C is １ and Y.I. ２ Furthermore, it was found that the molded articles containing the resin compositions of Examples 3 to 7, in which the total content of phosphorus-based antioxidants was less than 0.45 phr and the content of Celloxide 2021P was 0.25 phr or more and 0.4 phr or less, had a low y value of 0.40 and exhibited smaller changes in the color tone of light guided through long light guide paths.

[0152] Comparison of Examples 8 and 9 revealed that the inclusion of a polyorganosiloxane compound did not affect the color change of light guided through a long light path, nor did it affect the long-term heat resistance or long-term moist heat resistance.

[0153] The resin composition according to one embodiment of the present invention can produce a molded article that exhibits little change in the color tone of light guided through a long light guide path and has excellent long-term heat resistance and long-term moist heat resistance. Therefore, the molded article is suitable for use as a light guide part for a vehicle, and is particularly useful as a DRL part for a vehicle.

Claims

1. A polycarbonate resin composition comprising a polycarbonate resin, a phosphorus-based antioxidant, and an alicyclic epoxy compound, wherein the phosphorus-based antioxidant comprises a pentaerythritol diphosphite compound represented by the following general formula (1), the content of the alicyclic epoxy compound is 0.01 parts by mass or more and 0.6 parts by mass or less per 100 parts by mass of the polycarbonate resin, the content of the pentaerythritol diphosphite compound is 0.01 parts by mass or more and 0.35 parts by mass or less per 100 parts by mass of the polycarbonate resin, the content of the phosphorus-based antioxidant is 0.2 parts by mass or more per 100 parts by mass of the polycarbonate resin, and the ratio of the content of the alicyclic epoxy compound to the content of the pentaerythritol diphosphite compound is 0.7 or more: In formula (1), R Ｃ１１ ~R Ｃ１６ are (i) a hydrogen atom or an aromatic ring-containing group having 6 to 15 carbon atoms, which may be the same or different, or (ii) a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, which may be the same or different, with the proviso that R Ｃ１１ ~R Ｃ１６ Not all of them will be hydrogen atoms.

2. The polycarbonate resin composition according to claim 1, wherein the content of the pentaerythritol diphosphite compound is 0.05 parts by mass or more and 0.35 parts by mass or less per 100 parts by mass of the polycarbonate resin.

3. The polycarbonate resin composition according to claim 1 or 2, wherein the ratio of the content of said alicyclic epoxy compound to the content of said pentaerythritol diphosphite compound is 2.0 or more.

4. The polycarbonate resin composition according to any one of claims 1 to 3, wherein when a molded article for measuring optical properties is used, which is made of the polycarbonate resin composition and is equipped with an incident section where light is incident, an exit section where the incident light exits, and a light guide section that guides the light incident from the incident section to the exit section, and the light guide section has an optical path with a curvature that causes total reflection of the incident light, and the colorimetric measurement is performed using a white light-emitting diode as a light source, the y value of the molded article for measuring optical properties in the CIE 1931 color system at a position 1005 mm from the incident section of the light guide path is 0.41 or less.

5. The polycarbonate resin composition according to any one of claims 1 to 4, wherein a 5 mm thick molded article is produced using the polycarbonate resin composition by injection molding under manufacturing conditions of a cylinder temperature of 260°C, a mold temperature of 80°C, and a cycle time of 50 seconds, and after storing the molded article at 140°C for 1,000 hours, the YI value measured using a spectrophotometer under conditions of Illuminant C and a 2-degree field of view is 2.0 or less.

6. The polycarbonate resin composition according to any one of claims 1 to 5, wherein the polycarbonate resin comprises an aromatic polycarbonate resin whose main chain has a repeating unit represented by the following general formula (I): In formula (I), R Ａ１ and R Ａ２ is an alkyl or alkoxy group having 1 to 6 carbon atoms, and R Ａ１ and R Ａ２ and may be the same or different; X represents a single bond, an alkylene group having 1 to 8 carbon atoms, an alkylidene group having 2 to 8 carbon atoms, a cycloalkylene group having 5 to 15 carbon atoms, a cycloalkylidene group having 5 to 15 carbon atoms, -S-, -SO-, -SO ２ a and b each independently represent an integer of 0 to 4; when a is 2 or more, R Ａ１ may be the same or different, and when b is 2 or more, R Ａ２ may be the same or different.

7. In formula (1), R Ｃ１１ ~R Ｃ１６ are hydrogen atoms or aromatic ring-containing groups having 6 to 15 carbon atoms, and may be the same or different, provided that R Ｃ１１ ~R Ｃ１６ The polycarbonate resin composition according to any one of claims 1 to 6, wherein not all of the radicals are hydrogen atoms.

8. The polycarbonate resin composition according to any one of claims 1 to 7, wherein the pentaerythritol diphosphite compound represented by formula (1) is bis(2,4-dicumylphenyl)pentaerythritol diphosphite.

9. The polycarbonate resin composition according to any one of claims 1 to 8, further comprising at least one phosphorus-based antioxidant selected from the group consisting of aryl phosphite compounds represented by the following general formula (2) and aryl phosphine compounds represented by the following general formula (3): In formula (2), R Ｃ２１ ~R Ｃ２５ are hydrogen atoms, alkyl groups having 1 to 12 carbon atoms, or aryl groups having 6 to 14 carbon atoms, and may be the same or different, provided that R Ｃ２１ ~R Ｃ２５ cannot all be hydrogen atoms, and R Ｃ２１ ~R Ｃ２５ at least two of P-(R) are alkyl groups having 1 to 12 carbon atoms or aryl groups having 6 to 14 carbon atoms, Ｄ２１ ) ３ (3) In formula (3), R Ｄ２１ is a hydrocarbon group which may have a substituent, at least one of which is an aryl group having 6 to 18 carbon atoms, and a plurality of R Ｄ２１ may be the same or different.

10. The polycarbonate resin composition according to any one of claims 1 to 9, wherein the alicyclic epoxy compound comprises at least one selected from the group consisting of 3',4'-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate and bi-7-oxabicyclo[4.1.0]heptane.

11. A molded article comprising the polycarbonate resin composition according to any one of claims 1 to 10.

12. A molded article comprising a polycarbonate resin composition, which is a light-guiding component, the polycarbonate resin composition comprising a polycarbonate resin, a phosphorus-based antioxidant, and an alicyclic epoxy compound, the phosphorus-based antioxidant comprising a pentaerythritol diphosphite compound represented by the following general formula (1), the content of the alicyclic epoxy compound being 0.01 parts by mass or more and 0.6 parts by mass or less per 100 parts by mass of the polycarbonate resin, the content of the pentaerythritol diphosphite compound being 0.01 parts by mass or more and 0.35 parts by mass or less per 100 parts by mass of the polycarbonate resin, the content of the phosphorus-based antioxidant being 0.2 parts by mass or more per 100 parts by mass of the polycarbonate resin, and the ratio of the content of the alicyclic epoxy compound to the content of the pentaerythritol diphosphite compound being 0.5 or more: In formula (1), R Ｃ１１ ~R Ｃ１６ are (i) a hydrogen atom or an aromatic ring-containing group having 6 to 15 carbon atoms, which may be the same or different, or (ii) a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, which may be the same or different, with the proviso that R Ｃ１１ ~R Ｃ１６ Not all of them will be hydrogen atoms.

13. A molded article comprising a polycarbonate resin composition, which is a light-guiding part for vehicles, the polycarbonate resin composition comprising a polycarbonate resin, a phosphorus-based antioxidant, and an alicyclic epoxy compound, the phosphorus-based antioxidant comprising a pentaerythritol diphosphite compound represented by the following general formula (1), the content of the alicyclic epoxy compound being 0.01 parts by mass or more and 0.6 parts by mass or less per 100 parts by mass of the polycarbonate resin, the content of the pentaerythritol diphosphite compound being 0.01 parts by mass or more and 0.35 parts by mass or less per 100 parts by mass of the polycarbonate resin, the content of the phosphorus-based antioxidant being 0.2 parts by mass or more per 100 parts by mass of the polycarbonate resin, and the ratio of the content of the alicyclic epoxy compound to the content of the pentaerythritol diphosphite compound being 0.5 or more: In formula (1), R Ｃ１１ ~R Ｃ１６ are (i) a hydrogen atom or an aromatic ring-containing group having 6 to 15 carbon atoms, which may be the same or different, or (ii) a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, which may be the same or different, with the proviso that R Ｃ１１ ~R Ｃ１６ Not all of them will be hydrogen atoms.

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