Polycarbonate-based resin composition

Abstract

The present invention relates to a polycarbonate-based resin composition containing an aromatic polycarbonate resin (A), inorganic particles (B), and a liquid oil component (C), in which the average particle size of the inorganic particles (B) is 0.1-1 μm, the content of the inorganic particles is 0.00001-0.001 mass part per 100 mass parts of the aromatic polycarbonate resin (A), and, when the mass parts of the inorganic particles (B) per 100 mass parts of the aromatic polycarbonate resin (A) is taken as mB, the specific surface area of the inorganic particles (B) is taken as SB (m2 / g), and the mass parts of the liquid oil component (C) per 100 mass parts of the aromatic polycarbonate resin (A) is taken as mC, α determined by formula 1 is from more than 0.005 to less than 0.1.　Formula 1: α=(mB×SB) / mC

Description

Polycarbonate resin composition

[0001] The present invention relates to a polycarbonate resin composition, a method for producing the same, pellets thereof, and a molded article thereof.

[0002] 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 light-guiding members such as light guide plates, and various optical molded products such as lenses, optical fibers, etc. In recent years, polycarbonate resin compositions containing aromatic polycarbonate resins have been applied to light-guiding parts, such as inner lenses, that constitute daytime running lights (or Daytime Running Lamps; hereinafter also referred to as "DRLs") for vehicles such as automobiles and motorcycles, and light-guiding parts of various optical components.

[0003] In the application of polycarbonate-based resin compositions containing aromatic polycarbonate resins to DRLs, from the viewpoint of design, the ability to emit light uniformly in the surface direction when light is incident from the edge (hereinafter referred to as surface luminescence) is required. Furthermore, materials exhibiting surface luminescence are becoming larger in area and longer in length compared to conventional molded products. Surface luminescent materials are prone to changes in not only brightness but also color as the light guide length increases. This is due to reflection and partial light absorption occurring within the molded body compared to transparent materials. Since color is prone to change even with a slight increase in the light guide length, materials with minimal changes in brightness and color are required.

[0004] Polycarbonate-based resin compositions can cause silver streaks to form on the surface of molded articles, resulting in poor appearance of the molded articles. Recently, there has been a demand for reducing material waste in order to reduce environmental impact, and there is a particular demand for materials that can suppress the formation of silver streaks during molding and give molded articles with excellent appearance.

[0005] Patent Document 1 discloses a transparent resin composition containing a transparent resin and a specific amount of a light diffusing agent having an average particle diameter of 220 nm to 300 nm, as a resin molded product having excellent transparency, brightness, low colorability, and a good balance between transparency and brightness. Patent Document 2 discloses a polycarbonate resin composition containing a polycarbonate resin (A) and a specific amount of titanium oxide (B) having a specific number-average primary particle diameter and a specific number-average secondary particle diameter, as a polycarbonate resin composition that enables the production of a light guide plate or the like having excellent total light transmittance and haze, high brightness, a wide light emission range, and an extremely small number of bright spots.

[0006] International Publication No. 2019 / 172243 Japanese Patent Application Laid-Open No. 2020-7459

[0007] However, conventional polycarbonate resin compositions have not provided sufficient surface luminescence characteristics in resin molded articles obtained therefrom, which relate to changes in brightness and color depending on the light guide length.

[0008] The present invention aims to provide a polycarbonate resin composition that has surface luminescence properties with little change in brightness and color depending on the light guide length and that can give a resin molded article with excellent appearance, as well as pellets thereof and molded articles thereof.

[0009] That is, the present invention relates to the following [1] to

[10] . [1] A composition comprising an aromatic polycarbonate resin (A), inorganic particles (B), and a liquid oil component (C), wherein the average particle size of the inorganic particles (B) is 0.1 to 1 μm, the content of the inorganic particles (B) is 0.00001 to 0.001 parts by mass per 100 parts by mass of the aromatic polycarbonate resin (A), and the parts by mass of the inorganic particles (B) per 100 parts by mass of the aromatic polycarbonate resin (A) is m Ｂ , the specific surface area of ​​the inorganic particles (B) is S Ｂ (m ２ / g), and the parts by mass of the liquid oil component (C) relative to 100 parts by mass of the aromatic polycarbonate resin (A) is m Ｃ The polycarbonate resin composition has a value of α calculated by the following formula 1, which is greater than 0.005 and less than 0.1 when the formula 1 is: Ｂ ×S Ｂ ) / mＣ [2] The polycarbonate resin composition according to [1], wherein the inorganic particles (B) are titanium oxide. [3] The polycarbonate resin composition according to [1] or [2], further comprising an antioxidant (D), wherein the antioxidant (D) comprises at least one selected from the group consisting of phosphorus-based antioxidants and phenol-based antioxidants. [4] The polycarbonate resin composition according to [3], wherein the content of the antioxidant (D) is 0.001 to 1.0 part by mass per 100 parts by mass of the aromatic polycarbonate resin (A). [5] The polycarbonate resin composition according to [3], wherein the parts by mass of the antioxidant (D) per 100 parts by mass of the aromatic polycarbonate resin (A) is m Ｄ The polycarbonate resin composition according to [3] or [4], wherein β calculated by the following formula 2 is greater than 2.95 and less than 100 when m is Ｄ / (m Ｂ ×S Ｂ ) [In the formula, m Ｂ and S Ｂ as defined above]. [6] The polycarbonate resin composition according to any one of [1] to [5], wherein the aromatic polycarbonate resin (A) has a viscosity average molecular weight of 12,500 to 30,500. [7] The polycarbonate resin composition according to any one of [1] to [6], wherein the liquid oil component (C) contains at least one selected from the group consisting of paraffinic process oil, naphthenic process oil, aromatic process oil, and silicone oil. [8] The polycarbonate resin composition according to any one of [1] to [7], wherein the liquid oil component (C) is liquid at room temperature and has a kinematic viscosity at 40°C of 30 to 1,000 cSt. [9] Pellets comprising the polycarbonate resin composition according to any one of [1] to [8].

[10] A molded product comprising the polycarbonate resin composition according to any one of [1] to [8].

[0010] The present invention provides a polycarbonate resin composition having uniform surface luminescence with little change in brightness and color depending on the light guide length of the resin molding, and excellent appearance, as well as pellets thereof and moldings thereof.

[0011] Schematic diagram of a measuring device used for in-plane optical evaluation.

[0012] The polycarbonate resin composition of the present invention, its production method, pellets thereof, and molded articles thereof will be described in detail below. In this specification, any preferred definition may be adopted, and a combination of preferred definitions is more preferable. In this specification, the expression "XX to YY" means "XX or more and YY or less."

[0013] [Polycarbonate-based resin composition] The polycarbonate-based resin composition of the present invention comprises an aromatic polycarbonate resin (A), inorganic particles (B), and a liquid oil component (C), wherein the inorganic particles (B) have an average particle size of 0.1 to 1 μm, the content of the inorganic particles (B) is 0.00001 to 0.001 parts by mass relative to 100 parts by mass of the aromatic polycarbonate resin (A), and the parts by mass of the inorganic particles (B) relative to 100 parts by mass of the aromatic polycarbonate resin (A) is m Ｂ , the specific surface area of ​​the inorganic particles (B) is S Ｂ (m ２ / g), and the parts by mass of the liquid oil component (C) relative to 100 parts by mass of the aromatic polycarbonate resin (A) is m Ｃ When the value of α calculated by the following formula 1 is greater than 0.005 and less than 0.1, the formula 1 is: α = (m Ｂ ×S Ｂ ) / m Ｃ

[0014] [Aromatic Polycarbonate Resin (A)] The aromatic polycarbonate resin (A) contained in the polycarbonate resin composition of the present invention is not particularly limited, and those produced by known methods can be used. For example, those produced by reacting a dihydric phenol with a carbonate precursor by a solution method (interfacial polycondensation method) or a melt method (ester interchange method), that is, those produced by the interfacial polycondensation method of reacting a dihydric phenol with phosgene in the presence of a terminal terminator, or those produced by reacting a dihydric phenol with diphenyl carbonate or the like in the presence of a terminal terminator by an ester interchange method or the like can be used as the aromatic polycarbonate resin (A).

[0015] Examples of dihydric phenols include bis(hydroxyphenyl)alkane compounds such as 2,2-bis(4-hydroxyphenyl)propane (bisphenol A), bis(4-hydroxyphenyl)methane, 1,1-bis(4-hydroxyphenyl)ethane, and 2,2-bis(4-hydroxy-3,5-dimethylphenyl)propane, 4,4'-dihydroxydiphenyl, bis(4-hydroxyphenyl)cycloalkane, bis(4-hydroxyphenyl)oxide, bis(4-hydroxyphenyl)sulfide, bis(4-hydroxyphenyl)sulfone, bis(4-hydroxyphenyl)sulfoxide, bis(4-hydroxyphenyl)ketone, hydroquinone, resorcinol, and catechol. These may be used alone or in combination of two or more. Among these, bis(hydroxyphenyl)alkane compounds are preferred, with 2,2-bis(4-hydroxyphenyl)propane (bisphenol A), bis(4-hydroxyphenyl)methane, and 1,1-bis(4-hydroxyphenyl)ethane being more preferred, and bisphenol A being particularly preferred.

[0016] Carbonate precursors include carbonyl halides, carbonyl esters, and haloformates, such as phosgene, dihaloformates of dihydric phenols, diphenyl carbonate, dimethyl carbonate, and diethyl carbonate.

[0017] The aromatic polycarbonate resin (A) may have a branched structure. Examples of branching agents used to introduce a branched structure include 1,1,1-tris(4-hydroxyphenyl)ethane, α,α',α"-tris(4-hydroxyphenyl)-1,3,5-triisopropylbenzene, phloroglucin, trimellitic acid, and 1,3-bis(o-cresol).

[0018] Examples of the end terminator include monovalent carboxylic acids and derivatives thereof, and monovalent phenols. Specific examples include p-tert-butylphenol, p-phenylphenol, p-cumylphenol, p-perfluorononylphenol, p-(perfluorononylphenyl)phenol, p-(perfluorooxylphenyl)phenol, p-tert-perfluorobutylphenol, 1-(p-hydroxybenzyl)perfluorodecane, p-[2-(1H,1H-perfluorotridodecyloxy)-1,1,1,3,3,3-hexafluoropropyl]phenol, 3,5-bis(perfluorohexyloxycarbonyl)phenol, perfluorododecyl p-hydroxybenzoate, p-(1H,1H-perfluorooctyloxy)phenol, 2H,2H,9H-perfluorononanoic acid, and 1,1,1,3,3,3-hexafluoro-2-propanol.

[0019] The aromatic polycarbonate resin (A) is preferably a polycarbonate resin whose main chain has a repeating unit represented by the following general formula (I).

[0020]

[0021] (In the formula, R A1 and R A2 is an alkyl group or an 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-, -SO2-, -O- or -CO-, and 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.)

[0022] R A1 and R A2Examples 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 the above-mentioned alkyl group. 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.

[0023] 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 an alkylene group having 1 to 5 carbon atoms is 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 an alkylene group having 5 to 10 carbon atoms is 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 an alkylidene group having 5 to 10 carbon atoms is preferred, and an alkylidene group having 5 to 8 carbon atoms is more preferred. a and b are preferably 0 to 2, more preferably 0 or 1.

[0024] From the viewpoints of the transparency, mechanical properties, thermal properties, etc. of the resulting molded article, the aromatic polycarbonate resin (A) preferably contains a polycarbonate resin having a bisphenol A structure. Specific examples of polycarbonate resins having a bisphenol A structure include those represented by the general formula (I) in which X is an isopropylidene group. The content of the polycarbonate resin having a bisphenol A structure in the aromatic polycarbonate resin (A) 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, and even more preferably 85% by mass or more and 100% by mass or less.

[0025] The viscosity average molecular weight (Mv) of the aromatic polycarbonate resin (A) may be 12,500 to 30,500. From the viewpoint of sufficiently increasing the strength of molded articles, it is preferably 13,000 or more, more preferably 13,500 or more, and even more preferably 14,000 or more. From the viewpoint of sufficiently increasing the fluidity for molding processing, it is preferably 30,500 or less, more preferably 25,000 or less, and even more preferably 22,000 or less. That is, when the Mv is 12,500 to 30,500, the aromatic polycarbonate resin (A) can achieve both sufficiently high fluidity and sufficiently high molded article strength. 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 this, and then calculating it using the following formula: [η] = 1.23 × 10 -5 Mv 0.83

[0026] [Inorganic Particles (B)] The polycarbonate-based resin composition of the present invention contains inorganic particles (B) having an average particle size of 0.1 to 1 μm as a component for diffusing incident light. The inorganic particles (B) are not particularly limited as long as they are capable of diffusing incident light, and known inorganic particles such as titanium oxide, aluminum oxide, zinc oxide, zinc sulfide, and barium sulfate can be used. Among these, titanium oxide is preferred from the viewpoint of uniform surface emission. Titanium oxide particles themselves have excellent light diffusion properties, which is thought to enable uniform surface emission to be achieved efficiently. The inorganic particles (B) may be used alone or in combination of two or more types. When the inorganic particles (B) are titanium oxide, either a rutile or anatase crystal structure can be used. From the viewpoint of the thermal stability and light resistance of the polycarbonate-based resin composition, titanium oxide with a rutile structure is preferred.

[0027] The average particle size of the inorganic particles (B) is preferably 0.10 μm or more, more preferably 0.15 μm or more, and even more preferably 0.23 μm or more from the viewpoint of suppressing color change due to the light guide length when light is incident on a molded product, and is preferably 1.00 μm or less, more preferably 0.50 μm or less, and even more preferably 0.30 μm or less from the viewpoint of dispersibility. If the average particle size of the inorganic particles (B) is within the above preferred range, it is considered that the diffusion performance per particle of the inorganic particles (B) is improved and dispersibility is enhanced. The average particle size is the 50% cumulative particle size (D ５０ The BET specific surface area of ​​the inorganic particles (B) is preferably 1.44 m from the viewpoint of dispersibility of the inorganic particles. 2 / g or more, more preferably 2.88m 2 / g or more, more preferably 4.80m 2 / g or more, and from the viewpoint of suppressing a change in color tone of the molded product, it is preferably 14.4 m 2 / g or less, more preferably 9.59m 2 / g or less, more preferably 6.26m 2 / g or less. When the BET specific surface area of ​​the inorganic particles (B) is equal to or greater than the above-mentioned preferred value, it is believed that the cohesive force of the inorganic particles (B) is suppressed, resulting in improved dispersibility. Furthermore, when the BET specific surface area of ​​the inorganic particles (B) is equal to or less than the above-mentioned preferred value, it is believed that the interface between the surface of the inorganic particles (B) and the aromatic polycarbonate resin (A) serving as the base polymer is reduced, thereby suppressing deterioration of the aromatic polycarbonate resin (A) and preventing changes in the color tone of the molded product.

[0028] The inorganic particles (B) are preferably surface-treated inorganic particles from the viewpoint of dispersibility in a molded body. Examples of surface treatments include silicon dioxide (silica), zirconium oxide (zirconia), and aluminum hydroxide. The surface treatment preferably includes at least one selected from the group consisting of silicon dioxide (silica), zirconium oxide (zirconia), and aluminum hydroxide, and more preferably includes aluminum hydroxide. A more preferred inorganic particle is surface-treated titanium oxide.

[0029] The content of the inorganic particles (B) in the polycarbonate resin composition is preferably 0.00001 parts by mass or more, more preferably 0.00005 parts by mass or more, even more preferably 0.0001 parts by mass or more, and even more preferably 0.0003 parts by mass or more, relative to 100 parts by mass of the aromatic polycarbonate resin (A), from the viewpoint of improving brightness in the plane direction; and from the viewpoint of uniform plane light emission, it is preferably 0.001 parts by mass or less, more preferably 0.0009 parts by mass or less, even more preferably 0.0008 parts by mass or less, and even more preferably 0.0006 parts by mass or less. If the content of the inorganic particles (B) is equal to or greater than the above-mentioned preferred value, it is believed that the light diffusion performance is improved and the brightness in the plane direction is increased. Furthermore, if the content of the inorganic particles (B) is equal to or less than the above-mentioned preferred value, it is believed that the difference in brightness due to the light guide length can be suppressed and uniform plane light emission can be maintained.

[0030] [Liquid Oil Component (C)] The polycarbonate resin composition of the present invention contains a liquid oil component (C) from the viewpoint of improving the dispersibility of the inorganic particles (B). Examples of the liquid oil component (C) include paraffinic process oils (liquid paraffin), naphthenic process oils, aromatic process oils, and silicone oils, which are liquid at room temperature. The liquid oil component (C) may be used alone or in combination of two or more. From the viewpoint of availability, paraffinic process oils, naphthenic process oils, aromatic process oils, and silicone oils are preferred. From the viewpoint of allowing any viscosity to be selected, paraffinic process oils (liquid paraffin) and silicone oils are more preferred. From the viewpoint of minimizing color change when added to a resin, silicone oils are even more preferred. Commercially available paraffinic process oils include "Diana Process Oil PW-32," "Diana Process Oil PW-90," "Diana Process Oil PW-150," "Diana Process Oil PW-380," "Diana Process Oil PS-32," "Diana Process Oil PS-90," and "Diana Process Oil PS-430" (trade names, manufactured by Idemitsu Kosan Co., Ltd.), "Kaydol Oil," "ParaLux Oil" (trade names, manufactured by Chevron USA), and "Ragalrez 101" (trade name, manufactured by Eastman Chemical Co.). Commercially available naphthenic process oils include "Diana Process Oil NS-1000," "Diana Process Oil NS-90S," and "Diana Process Oil NR-26" and "Diana Process Oil NM-280" (trade names, manufactured by Idemitsu Kosan Co., Ltd.). Commercially available aromatic process oils include "Diana Process Oil AC-12," "Diana Process Oil AC-460," "Diana Process Oil NP-250," and "Diana Process Oil AH-16" (product names, manufactured by Idemitsu Kosan Co., Ltd.).

[0031] Examples of polysiloxane-based silicone oils include dimethyl silicone oil, phenylmethyl silicone oil, diphenyl silicone oil, and fluorinated alkyl silicone. Commercially available silicone oils include the "KF-96" series, "KR-510" (product names, manufactured by Shin-Etsu Chemical Co., Ltd.), "DOWSIL SH-510 Fluid," and "DOWSIL FS-1265 Fluid" (product names, manufactured by Dow-Toray Industries, Inc.).

[0032] The liquid oil component (C) may be, for example, liquid at room temperature and have a kinematic viscosity of 5 to 1,000 cSt at 40° C. The liquid oil component (C) is preferably liquid at room temperature and has a kinematic viscosity of 30 to 1,000 cSt at 40° C., more preferably 30 to 500 cSt, and even more preferably 50 to 350 cSt. From the viewpoint of improving the dispersibility of the inorganic particles (B), the kinematic viscosity of the liquid oil component (C) at 40° C. is preferably 30 cSt or more, more preferably 50 cSt or more, even more preferably 60 cSt or more, and even more preferably 70 cSt or more, and is preferably 500 cSt or less, more preferably 350 cSt or less, even more preferably 200 cSt or less, and even more preferably 150 cSt or less. When the kinematic viscosity of the liquid oil component (C) at 40°C is equal to or higher than the above-mentioned preferred value, it is believed that the inorganic particles (B) are well dispersed in the liquid oil component (C) without settling. On the other hand, when the kinematic viscosity is equal to or lower than the above-mentioned preferred value, it is believed that the liquid oil component (C) well coats the surfaces of the inorganic particles (B), and the inorganic particles (B) are dispersed in the liquid oil component (C) without agglomerating. The kinematic viscosity at 40°C is measured in accordance with JIS K2283:2000.

[0033] The content of the liquid oil component (C) in the polycarbonate resin composition is preferably 0.005 parts by mass or more, more preferably 0.01 parts by mass or more, even more preferably 0.03 parts by mass or more, and even more preferably 0.05 parts by mass or more, relative to 100 parts by mass of the aromatic polycarbonate resin (A) from the viewpoint of dispersibility of the inorganic particles, and from the viewpoint of suppressing the occurrence of silver streaks in the molded article, it is preferably 0.5 parts by mass or less, more preferably 0.4 parts by mass or less, even more preferably 0.3 parts by mass or less, and even more preferably 0.2 parts by mass or less. When the content of the liquid oil component (C) is equal to or more than the above-mentioned preferred value, it is considered that a sufficient amount of the liquid oil component (C) is mixed relative to the amount of the inorganic particles (B) added, and the inorganic particles (B) are well dispersed in the liquid oil component (C).

[0034] [Antioxidant (D)] The polycarbonate resin composition of the present invention preferably further contains an antioxidant (D) from the viewpoint of preventing discoloration and the like due to oxidative degradation of the resin. The antioxidant (D) preferably contains at least one selected from the group consisting of phosphorus-based antioxidants and phenol-based antioxidants. The antioxidant (D) may be used alone or in combination of two or more.

[0035] As the phosphorus-based antioxidant, from the viewpoint of obtaining a resin composition that can suppress discoloration and the like even when retained at high temperatures, phosphite-based antioxidants and phosphine-based antioxidants are preferred.

[0036] Examples of the phosphite antioxidant include trisnonylphenyl phosphite, triphenyl phosphite, tridecyl phosphite, trioctadecyl phosphite, tris(2,4-di-tert-butylphenyl)phosphite (trade name "Irgafos 168" manufactured by BASF, trade name "ADK STAB 2112" manufactured by ADEKA Corporation, etc.), bis-(2,4-di-tert-butylphenyl)pentaerythritol-diphosphite (trade name "Irgafos 126" manufactured by BASF, trade name "ADK STAB PEP-24G" manufactured by ADEKA Corporation, etc.), bis-(2,4-di-tert-butyl-6-methylphenyl)ethyl phosphite (trade name "Irgafos 126" manufactured by BASF, trade name "ADK STAB PEP-24G" manufactured by ADEKA Corporation, etc.), and bis-(2,4-di-tert-butyl-6-methylphenyl)ethyl phosphite (trade name "Irgafos 126" manufactured by BASF, trade name "ADK STAB PEP-24G" manufactured by ADEKA Corporation, etc.). 38"), bis-(2,6-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphite (trade name "ADEKA STAB PEP-36" manufactured by ADEKA Corporation, etc.), distearyl-pentaerythritol diphosphite (trade name "ADEKA STAB PEP-8" manufactured by ADEKA Corporation, trade name "JPP-2000" manufactured by Johoku Chemical Industry Co., Ltd., etc.), [bis(2,4-di-tert-butyl-5-methylphenoxy)phosphino]biphenyl (trade name "GSY-P101" manufactured by Osaki Kogyo Co., Ltd., etc.), 2-tert-butyl-6-methyl-4-[3-(2,4,8,10-tetra-tert-butylbenzo[d][1,3,2]benzodioxaphosphepin-6-yl)oxypropyl]phenol (trade name "Sumilizer" manufactured by Sumitomo Chemical Co., Ltd., GP" and the like), tris[2-[[2,4,8,10-tetra-tert-butyldibenzo[d,f][1,3,2]dioxaphosphepin-6-yl]oxy]ethyl]amine (trade name "Irgafos 12" manufactured by BASF and the like), and bis(2,4-dicumylphenyl)pentaerythritol diphosphite (trade name "Doverphos S-9228PC" manufactured by Dover Chemical Corporation).

[0037] Among these phosphite-based antioxidants, from the viewpoint of preventing coloration and the like, tris(2,4-di-tert-butylphenyl)phosphite ("Irgafos 168"), bis(2,6-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphite ("ADK STAB PEP-36"), bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphite, bis(2,4-dicumylphenyl)pentaerythritol diphosphite ("Doverphos S-9228PC"), and 2-tert-butyl-6-methyl-4-[3-(2,4,8,10-tetra-tert-butylbenzo[d][1,3,2]benzodioxaphosphepin-6-yl)oxypropyl]phenol (trade name "Sumilizer GP", etc.) are preferred. Particularly preferred is bis(2,6-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphite ("ADK STAB PEP-36").

[0038] An example of the phosphine-based antioxidant is triphenylphosphine (trade name "JC263" manufactured by Johoku Chemical Industry Co., Ltd.).

[0039] Examples of phenolic antioxidants include hindered phenols such as n-octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, 2,6-di-tert-butyl-4-methylphenol, 2,2′-methylenebis(4-methyl-6-tert-butylphenol), and pentaerythrityl-tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate].

[0040] Examples of commercially available phenolic antioxidants include those manufactured by BASF under the trade names "Irganox 1010," "Irganox 1076," "Irganox 1330," "Irganox 3114," and "Irganox 3125," those manufactured by Takeda Pharmaceutical Co., Ltd. under the trade name "BHT," those manufactured by Cyanamid Corporation under the trade name "Cyanox 1790," and those manufactured by Sumitomo Chemical Co., Ltd. under the trade name "Sumilizer GA-80."

[0041] The content of the antioxidant (D) in the polycarbonate resin composition of the present invention may be 0.001 to 1.0 parts by mass per 100 parts by mass of the aromatic polycarbonate resin (A). From the viewpoint of suppressing coloration, the content is preferably 0.001 or more, more preferably 0.005 or more, more preferably 0.01 or more, and even more preferably 0.05 or more. From the viewpoint of economic efficiency, the content is preferably 0.5 or less, more preferably 0.2 or less, and even more preferably 0.1 or less. When the content of the antioxidant (D) is equal to or greater than the above-mentioned preferred values, it is believed that coloration due to oxidative degradation of the resin can be suppressed. Furthermore, when the content is equal to or less than the above-mentioned preferred values, the amount of the antioxidant (D), which tends to be expensive, is used in an appropriate amount, improving economic efficiency and also tending to suppress the occurrence of mold deposits, which are a concern when an excessive amount of antioxidant is used during molding.

[0042] [Other Additives] The polycarbonate resin composition of the present invention may further contain other additives within the range that does not impair the effects of the present invention. Examples of other components include a mold release agent, a hydrolysis stabilizer, an ultraviolet absorber, a flame retardant, a flame retardant aid, a reinforcing material, a filler, an impact resistance improving elastomer, a pigment, a dye, etc.

[0043] [Physical Properties of Polycarbonate Resin Composition] The polycarbonate resin composition of the present invention has a polycarbonate resin composition in which the parts by mass of the inorganic particles (B) relative to 100 parts by mass of the aromatic polycarbonate resin (A) is m Ｂ , the specific surface area of ​​the inorganic particles (B) is S Ｂ (m ２ / g), and the parts by mass of the liquid oil component (C) relative to 100 parts by mass of the aromatic polycarbonate resin (A) is m Ｃ When the value of α calculated by the following formula 1 is greater than 0.005 and less than 0.1, the formula 1 is: α = (m Ｂ ×S Ｂ ) / m Ｃ α is m Ｂ and S Ｂ The product of m Ｃ From the viewpoint of obtaining uniform surface luminescence, α is preferably 0.005 m ２ / g or more, more preferably 0.010m ２ / g or more, more preferably 0.015m ２ / g or more, and from the viewpoint of improving the color tone and appearance of the molded product, it is preferably 0.1 m ２ / g or less, more preferably 0.08m ２ / g or less, more preferably 0.06m ２ / g or less. When a sufficient amount of liquid oil component (C) is mixed with respect to the total surface area of ​​inorganic particles (B), it is believed that the inorganic particles (B) will be well dispersed. Furthermore, when the amount of liquid oil component (C) used with respect to the total surface area of ​​inorganic particles (B) is not excessive, it is believed that deterioration in color tone and the occurrence of silver streaks in the molded article will be suppressed. From this viewpoint, it is preferable that α is in the above-mentioned range.

[0044] When the polycarbonate resin composition of the present invention contains an antioxidant (D), the parts by mass of the antioxidant (D) relative to 100 parts by mass of the aromatic polycarbonate resin (A) is m Ｄ , the mass parts of the inorganic particles (B) relative to 100 mass parts of the aromatic polycarbonate resin (A) is m Ｂ , the specific surface area of ​​the inorganic particles (B) is S Ｂ (m ２ / g), β calculated by the following formula 2 may be, for example, greater than 1.5 and less than 200. β is preferably greater than 2.95 and less than 100, more preferably greater than 2.95 and less than 200, even more preferably greater than 2.95 and less than 100, and even more preferably greater than 3 and less than 60. Formula 2: β = m Ｄ / (m Ｂ ×S Ｂ ) [In the formula, m Ｂ and S Ｂ is the same as above. β is m Ｄ No, m Ｂ and S Ｂis the ratio to the product of (B) and (C). From the viewpoint of suppressing color change, β is preferably greater than 1.5, more preferably greater than 2.95, even more preferably 3 or more, even more preferably greater than 3, more preferably 4 or more, and even more preferably 5 or more. From the viewpoint of economic efficiency, it is preferably less than 200, more preferably less than 100, even more preferably 60 or less, even more preferably less than 60, even more preferably 30 or less, and even more preferably 15 or less. When β is equal to or greater than the above-mentioned preferred value, the amount of antioxidant (D) at the interface between the active sites on the surface of the inorganic particles (B) and the aromatic polycarbonate resin (A) as the base polymer is sufficient, and it is thought that color change due to deterioration of the aromatic polycarbonate resin (A) can be suppressed. Furthermore, when β is equal to or less than the above-mentioned preferred value, the amount of antioxidant (D), which tends to be expensive, used is appropriate for the interface between the inorganic particles (B), which are active sites, and the aromatic polycarbonate resin (A) as the base polymer.

[0045] Molded articles of the polycarbonate-based resin composition of the present invention have a certain degree of luminance regardless of the light guide length. In other words, they have uniform surface luminance. The luminance due to differences in the light guide length can be evaluated by measuring the surface luminance at a portion close to the light source (e.g., a light guide length of 25 mm) and at a portion far from the light source (e.g., a light guide length of 125 mm). The luminance is usually expressed as luminance [unit: cd / m ２ ]

[0046] The molded article of the polycarbonate resin composition of the present invention has a small change in color depending on the light guide length and is excellent in color uniformity. The color uniformity is measured by measuring the y value of the CIE 1931 color space at a measurement angle of 1 degree on the molded article, and the measured value at a light guide length of 125 mm is taken as the y value. １２５ , the measurement value of 75 mm is y ７５ When γ is set to γ, it can be calculated by the following formula 3. γ calculated by the following formula 3 is preferably less than 1.1, more preferably less than 1.08, even more preferably less than 1.06, and even more preferably less than 1.05. Formula 3: γ=y １２５ / y ７５ γ is y １２５ No, y ７５γ is a ratio of 1.0 when the light guide color tone does not change at all when the light guide length is changed, and the closer to this value, the better the color uniformity.

[0047] [Method for Producing Polycarbonate-Based Resin Composition] The method for producing the polycarbonate-based resin composition of the present invention is not particularly limited. The polycarbonate-based resin composition can be produced by mixing and melt-kneading the aromatic polycarbonate resin (A), inorganic particles (B), and liquid oil component (C), as well as, if necessary, the antioxidant (D) and other additives, in any order. The melt-kneading can be carried out by a commonly used method, such as a method using a single-screw extruder, twin-screw extruder, co-kneader, or multi-screw extruder. Among these, a twin-screw extruder is preferred from the viewpoints of productivity and versatility. The heating temperature during melt-kneading is preferably 200°C or higher, more preferably 220°C or higher, and even more preferably 240°C or higher, from the viewpoint of dispersibility of the inorganic particles (B). It is also preferably 300°C or lower, more preferably 290°C or lower, and even more preferably 280°C or lower, from the viewpoint of suppressing coloration of the molded product. If the heating temperature during melt-kneading is equal to or higher than the above-mentioned preferred value, it is believed that the viscosity of the aromatic polycarbonate resin (A) increases, and the inorganic particles (B) are well dispersed during kneading. Furthermore, if the heating temperature is equal to or lower than the above-mentioned preferred value, it is believed that deterioration of the aromatic polycarbonate resin (A) due to heat is suppressed, and coloration of the molded product is suppressed. It is preferable to adjust the residence time to 10 minutes or less. Furthermore, it is preferable that the screw has at least one or more counter-tooth screw elements or kneading disks, and that melt-kneading is performed while the mixture is partially retained in those locations.

[0048] In the method for producing a polycarbonate resin composition of the present invention, it is preferable to first mix the inorganic particles (B) with the liquid oil component (C) and then mix them with other components. In this case, it is preferable to disperse the inorganic particles (B) in the liquid oil component (C). For example, an ultrasonic oscillator or ultrasonic vibrator can be used to disperse the inorganic particles (B). From the viewpoint of dispersibility of the inorganic particles (B), the set frequency of the ultrasonic oscillator, ultrasonic vibrator, or other device is preferably 3 kHz or higher, more preferably 4 kHz or higher, and even more preferably 5 kHz or higher, and preferably 1000 kHz or lower, more preferably 400 kHz or lower, and even more preferably 100 kHz or lower. If the frequency is higher than the above-mentioned preferred value, dispersion of fine particles is promoted. Furthermore, if the frequency is lower than the above-mentioned preferred value, the inorganic particles (B) in the viscous liquid oil component (C) can be efficiently dispersed by a high physical impact force. The ultrasonic treatment time is preferably 3 minutes or more, more preferably 4 minutes or more, and even more preferably 5 minutes or more from the viewpoint of dispersibility of the inorganic particles (B) in the liquid oil component (C), and is preferably 30 minutes or less, more preferably 15 minutes or less, and even more preferably 30 minutes or less from the viewpoint of mass productivity. If the ultrasonic treatment time is not more than the above-mentioned preferred value, the working time can be shortened and mass productivity can be ensured.

[0049] [Pellets and Molded Articles] The pellets of the present invention can be obtained through the melt-kneading in the above-mentioned production method. The pelletizing method is not particularly limited, and examples thereof include a method of cooling and cutting the melt-kneaded product. Specific examples include a hot-cut method, a strand-cut method, and an underwater-cut method. From the viewpoint of stability of plasticization and weighing during molding, the mass per 50 pellets is preferably 0.3 g or more, more preferably 0.4 g or more, even more preferably 0.5 g or more, and preferably 3.0 g or less, more preferably 1.8 g or less, and even more preferably 1.5 g or less. By having the mass per 50 pellets be equal to or greater than the above-mentioned preferred value, or by having the mass per 50 pellets be within the above-mentioned preferred range, a constant amount of pellets can be fed to a molding machine and uniformly plasticized in the cylinder, thereby maintaining stability during molding processing.

[0050] The molded article of the present invention can be produced by injection molding, injection compression molding, extrusion molding, blow molding, press molding, vacuum molding, foam molding, or the like using a melt-kneaded product of the polycarbonate resin composition or the pellets as a raw material. It is particularly preferred to produce a molded article by injection molding or injection compression molding using the obtained pellets. A preferred method for producing a molded article includes a step of injection-molding a resin composition containing an aromatic polycarbonate resin under conditions of a cylinder temperature of 220 to 300°C or less and a residence time of 60 to 2000 seconds or less.

[0051] The molded article of the present invention can be suitably used as, for example, exterior and internal parts of electrical and electronic devices such as televisions, radios, cameras, video cameras, audio players, DVD players, air conditioners, mobile phones, smartphones, transceivers, displays, computers, tablet devices, portable game devices, stationary game devices, wearable electronic devices, cash registers, calculators, copiers, printers, facsimiles, communication base stations, batteries, and robots; exterior and internal parts of automobiles, railways, ships, aircraft, space industry equipment, and medical equipment; and building material parts. Particularly suitable are parts for vehicle lighting fixtures for automobiles and motorcycles, and particularly preferred are internal parts for such vehicle lighting fixtures. Preferred vehicle lighting fixtures include vehicle front lamps, vehicle rear lamps, vehicle exterior communication lamps, vehicle interior lights (ambient lamps), and DRL lamps.

[0052] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0053] The components used in the examples and comparative examples are as follows: <Aromatic polycarbonate resin (A)> (A-1): "Taflon FN1300" (manufactured by Taihaku Idemitsu Petrochemical Co., Ltd., bisphenol A polycarbonate resin, viscosity average molecular weight (Mv) = 11,500) (A-2): "Taflon FN1500" (manufactured by Taihaku Idemitsu Petrochemical Co., Ltd., bisphenol A polycarbonate resin, viscosity average molecular weight (Mv) = 14,400) (A-3): "Taflon FN1700" (manufactured by Taihaku Idemitsu Petrochemical Co., Ltd., bisphenol A polycarbonate resin, viscosity average molecular weight (Mv) = 17,700)

[0054] <Inorganic particles (B)> (B-1): "TTO-55(A)" (manufactured by Ishihara Sangyo Kaisha, Ltd., rutile-type titanium oxide, aluminum hydroxide surface treatment, average particle size 0.04 μm, specific surface area 35.97 m) ２ / g) (B-2): "CR-60" (manufactured by Ishihara Sangyo Kaisha, Ltd., rutile-type titanium oxide, aluminum hydroxide surface treatment, average particle size 0.21 μm, specific surface area 6.85 m ２ / g) (B-3): "CR-50" (manufactured by Ishihara Sangyo Kaisha, Ltd., rutile-type titanium oxide, aluminum hydroxide surface treatment, average particle size 0.25 μm, specific surface area 5.76 m ２ / g) (B-4): "CR-58" (manufactured by Ishihara Sangyo Kaisha, Ltd., rutile-type titanium oxide, aluminum hydroxide surface treatment, average particle size 0.28 μm, specific surface area 5.14 m ２ / g) (B-5): "R-38L" (manufactured by Sakai Chemical Industry Co., Ltd., rutile-type titanium oxide, aluminum hydroxide surface treatment, average particle size 0.40 μm, specific surface area 3.60 m ２ / g) (B-6): "PT-301" (manufactured by Ishihara Sangyo Kaisha, Ltd., rutile-type titanium oxide, no surface treatment, average particle size 0.25 μm, specific surface area 5.76 m ２ / g) (B-7): "PT-401" (manufactured by Ishihara Sangyo Kaisha, Ltd., rutile-type titanium oxide, no surface treatment, average particle size 0.07 μm, specific surface area 20.55 m ２ / g) (B-8): "PC-3" (manufactured by Ishihara Sangyo Kaisha, Ltd., rutile-type titanium oxide, aluminum hydroxide, silicon dioxide, and methyl hydrogen polysiloxane surface treatment, average particle size 0.21 μm, specific surface area 6.85 m ２ / g) (Method of measuring average particle diameter) The average particle diameter was determined by the 50% cumulative particle diameter (D ５０ ) was measured as follows. Using platinum (Pt) as the target, inorganic particles (B) were subjected to sputtering treatment using a sputtering device with a coating time of 30 seconds. The inorganic particles (B) subjected to the sputtering treatment were photographed with a scanning electron microscope ("Regulus 8200", manufactured by Hitachi High-Tech Corporation), and the obtained image was analyzed using image analysis software ("Image pro plus", manufactured by Media Cybernetics) to determine the particle size by dividing the sum of the major axis and minor axis of the inorganic particle by 2. Using the same method, the particle sizes of 100 or more inorganic particles were randomly measured, and the value calculated as the average was taken as the average particle size. (Method for measuring specific surface area) The specific surface area was measured by the BET method using a specific surface area measuring device in accordance with JIS Z8830:2013.

[0055] <Liquid Oil Component (C)> (C-1): "Diana Process Oil PW-32" (manufactured by Idemitsu Kosan Co., Ltd., paraffinic process oil (liquid paraffin), kinematic viscosity at 40°C of 31 cSt) (C-2): "Diana Process Oil PW-380" (manufactured by Idemitsu Kosan Co., Ltd., paraffinic process oil (liquid paraffin), kinematic viscosity at 40°C of 409 cSt) (C-3): "Diana Process Oil NS-100" (manufactured by Idemitsu Kosan Co., Ltd., naphthenic process oil, kinematic viscosity at 40°C of 95 cSt) (C-4): "Diana Process Oil AC-460" (manufactured by Idemitsu Kosan Co., Ltd., aromatic process oil, kinematic viscosity at 40°C of 460 cSt) (C-5): "KF-96-10cs" (manufactured by Shin-Etsu Chemical Co., Ltd., dimethyl silicone oil, kinematic viscosity at 40°C of 8 to 10 cSt) (C-6): "KF-96-100cs" (manufactured by Shin-Etsu Chemical Co., Ltd., dimethyl silicone oil, kinematic viscosity at 40°C of 80 to 95 cSt) (C-7): "KF-96-1000cs" (manufactured by Shin-Etsu Chemical Co., Ltd., dimethyl silicone oil, kinematic viscosity at 40°C of 800 to 930 cSt)

[0056] <Antioxidants (D)> (D-1): "ADK STAB PEP-36" (manufactured by ADEKA Corporation, bis(2,6-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphite) (D-2): "ADK STAB 2112" (manufactured by ADEKA Corporation, tris(2,4-di-tert-butylphenyl)phosphite) (D-3): "Doverphos S-9228PC" (manufactured by Dover Chemical Co., bis(2,4-dicumylphenyl)pentaerythritol diphosphite) (D-4): "Sumilizer GP" (manufactured by Sumitomo Chemical Co., Ltd., 6-[3-(3-t-butyl-4-hydroxy-5-methylphenyl)propoxy]-2,4,8,10-tetra-t-butyldibenz[d,f][1,3,2]dioxaphospepine)

[0057] Examples 1 to 29, Comparative Examples 1 to 7 (1. Production of Resin Compositions) Using a twin-screw extruder (Toshiba Machine Co., Ltd., "TEM-37SS," L / D = 40.5, equipped with a vent), the cylinder temperature was set to 260°C, and the components shown in Tables 1 to 7 were mixed. At this time, the inorganic particles (B) were previously mixed with the liquid oil component (C), and the mixture was shaken for 5 minutes at a frequency of 40 kHz using an ultrasonic oscillator, and then mixed together with the other components. The resulting mixture was fed from the main throat of the extruder using a quantitative feeder, and the resin kneaded product was extruded into a strand shape at a discharge rate of 40 kg / hour and a screw rotation speed of 180 rpm. The extruded product was then quenched in a strand bath and cut with a strand cutter to obtain a resin composition in the form of pellets.

[0058] The values ​​of α calculated by the following formula 1 and β calculated by the following formula 2 are shown in Tables 1 to 7. Formula 1: α = (m Ｂ ×S Ｂ ) / m Ｃ Equation 2: β = m Ｄ / (m Ｂ ×S Ｂ In Formula 1 and Formula 2, m Ｂ , S Ｂ , m Ｃ and m Ｄ is as follows: m Ｂ S: parts by mass of inorganic particles (B) relative to 100 parts by mass of aromatic polycarbonate resin (A), Ｂ : specific surface area of ​​inorganic particles (B) m Ｃ m: parts by mass of the liquid oil component (C) relative to 100 parts by mass of the aromatic polycarbonate resin (A) Ｄ : parts by mass of antioxidant (D) relative to 100 parts by mass of aromatic polycarbonate resin (A)

[0059] (2. In-plane Optical Evaluation) [Preparation of Flat Test Specimens] The pellet-shaped resin composition obtained above was used in an injection molding machine ("EC180SX" manufactured by Shibaura Machine Co., Ltd.) to obtain flat test specimens measuring 150 mm wide x 150 mm long x 4 mm thick. The molding conditions were a cylinder temperature of 260°C and a mold temperature of 80°C. Because the resin pellets absorb moisture, they were dried at 120°C for 5 hours immediately before molding. [Evaluation] The flat test specimens obtained above were quantitatively evaluated for light emitted in the in-plane direction from the molded article using the measuring device shown in Figure 1. Specifically, light was incident on the molded article (flat test specimen) 1 from the light incident surface 2, and the light guide luminance and color tone in the in-plane direction were measured. A black rubber plate was placed opposite the measurement surface of the molded article 1 to prevent light reflection, and an LED light source 4 containing 30 LED chips 3 ("BRT300BL1" manufactured by Bright Co., Ltd.) was placed adjacent to the light incident surface 2. The voltage value of the power supply device 5 connected to the LED light source was set to 32 V, and the current value was set to 0.23 A, thereby adjusting the output of the light source. <(1) Brightness (light guide length 25 mm)> The brightness of the flat test piece obtained above was measured at a measurement angle of 1 degree using a color brightness meter "CS-1000" (manufactured by Konica Minolta Japan Inc.). The results are shown in Tables 1 to 7. The higher this value, the better the surface emission brightness in the area closer to the light source. From the viewpoint of uniform surface emission, the appropriate brightness in this example (light guide length 25 mm) was 1000 cd / m ２ ~2600 cd / m ２ <(2) Brightness (light guide length 125 mm)> The brightness of the flat test piece obtained above was measured at a measurement angle of 1 degree using a color brightness meter "CS-1000" (manufactured by Konica Minolta Japan Inc.). The results are shown in Tables 1 to 7. The higher this value, the more excellent the surface emission brightness is at a portion farther from the light source. From the viewpoint of uniform surface emission, the appropriate brightness in this example (light guide length 125 mm) is 561 cd / m ２ (3) Color uniformity The flat test piece obtained above was measured for the y value in the CIE 1931 color space at a measurement angle of 1 degree using a color luminance meter "CS-1000" (manufactured by Konica Minolta Japan, Inc.). The measured value at a light guide length of 125 mm was defined as the y value. １２５ , the measurement value of 75 mm is y ７５The color uniformity γ was calculated according to formula 3. The results are shown in Tables 1 to 7. The closer the color uniformity is to 1.000, the smaller the change in color due to the light guide length. Formula 3: γ = y １２５ / y ７５

[0060] (3. Appearance Evaluation) [Preparation of Flat Test Pieces] The pellet-shaped resin composition obtained above was used in an injection molding machine ("EC180SX" manufactured by Shibaura Machine Co., Ltd.) to obtain flat test pieces measuring 150 mm wide x 150 mm long x 4 mm thick. The molding conditions were a cylinder temperature of 260°C and a mold temperature of 80°C. Since the resin pellets absorb moisture, they were dried at 120°C for 5 hours immediately before molding. [Evaluation] <Appearance Evaluation> One hundred flat test pieces obtained above were molded in succession, and the number of pieces with silver streaks on the appearance was counted. The results are shown in Tables 1 to 7. The fewer the number of silver streaks, the better the appearance of the molded product. 1: 0 to 2 2: 3 to 8 3: 9 to 14 4: 15 to 19 5: 20 or more

[0061]

[0062]

[0063]

[0064]

[0065]

[0066]

[0067]

[0068] REFERENCE SIGNS LIST 1 Molded product (flat test piece) 2 Light incident surface 3 LED chip 4 LED light source 5 Power supply device

Claims

1. The composition comprises an aromatic polycarbonate resin (A), inorganic particles (B), and a liquid oil component (C), The inorganic particles (B) have an average particle size of 0.1 to 1 μm, the content of the inorganic particles (B) is 0.00001 to 0.001 parts by mass per 100 parts by mass of the aromatic polycarbonate resin (A), The parts by mass of the inorganic particles (B) relative to 100 parts by mass of the aromatic polycarbonate resin (A) is m Ｂ , the specific surface area of the inorganic particles (B) is S Ｂ (m ２ / g), and the parts by mass of the liquid oil component (C) relative to 100 parts by mass of the aromatic polycarbonate resin (A) is m Ｃ and α, calculated by the following formula 1, is greater than 0.005 and less than 0.1: Formula 1: α = (m Ｂ × S Ｂ ) / m Ｃ

2. 2. The polycarbonate resin composition according to claim 1, wherein the inorganic particles (B) are titanium oxide.

3. 3. The polycarbonate resin composition according to claim 1 or 2, further comprising an antioxidant (D), wherein the antioxidant (D) comprises at least one selected from the group consisting of phosphorus-based antioxidants and phenol-based antioxidants.

4. 4. The polycarbonate resin composition according to claim 3, wherein the content of the antioxidant (D) is 0.001 to 1.0 part by mass per 100 parts by mass of the aromatic polycarbonate resin (A).

5. The parts by mass of the antioxidant (D) relative to 100 parts by mass of the aromatic polycarbonate resin (A) is m Ｄ 4. The polycarbonate resin composition according to claim 3, wherein β calculated by the following formula 2 is more than 2.95 and less than 200: Formula 2: β = m Ｄ / (m Ｂ ×S Ｂ ) [In the formula, m Ｂ and S Ｂ is the same as above.

6. 3. The polycarbonate resin composition according to claim 1, wherein the aromatic polycarbonate resin (A) has a viscosity average molecular weight of 12,500 to 30,500.

7. 3. The polycarbonate resin composition according to claim 1, wherein the liquid oil component (C) comprises at least one selected from the group consisting of paraffinic process oil, naphthenic process oil, aromatic process oil, and silicone oil.

8. 3. The polycarbonate resin composition according to claim 1, wherein the liquid oil component (C) is liquid at room temperature and has a kinematic viscosity at 40°C of 30 to 1,000 cSt.

9. A pellet comprising the polycarbonate resin composition according to claim 1 or 2.

10. A molded article made of the polycarbonate resin composition according to claim 1 or 2.