Thermoplastic resin composition and molded article

Abstract

To obtain a thermoplastic resin composition capable of providing a high-quality molded product.SOLUTION: The thermoplastic resin composition comprises a polycarbonate resin (A), a thermoplastic resin (B) and a fatty acid metal salt (C). The polycarbonate resin (A) contains a structural unit represented by the formula (1). The thermoplastic resin (B) is a thermoplastic resin other than the polycarbonate resin (A). The fatty acid metal salt is a metal salt of a saturated or unsaturated fatty acid having 4 or more carbon atoms. The content of the fatty acid metal salt (C) is 0.00001 parts by mass or more and less than 0.02 parts by mass based on 100 parts by mass of the total of the polycarbonate resin (A) and the thermoplastic resin (B).SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a thermoplastic resin composition containing a polycarbonate resin having a plant-derived component, and a molded article made using the same. [Background technology]

[0002] Polycarbonate resins are generally produced using raw materials derived from petroleum resources. However, in recent years, concerns have arisen about the depletion of petroleum resources, and there is a demand for polycarbonate resins made from raw materials obtained from biomass resources such as plants. In addition, there are concerns that global warming due to the increase and accumulation of carbon dioxide emissions will lead to climate change, and therefore there is a demand for the development of polycarbonate resins made from plant-derived monomers that are carbon-neutral even when disposed of after use. For example, Patent Document 1 discloses that isosorbide (hereinafter, sometimes referred to as "ISB") is used as a plant-derived monomer, and a polycarbonate resin is obtained by transesterification with diphenyl carbonate.

[0003] Polycarbonate resins obtained using isosorbide (hereinafter, sometimes referred to as "isosorbide-based polycarbonate resins") not only have excellent optical properties, but also have significantly better weather resistance and surface hardness than conventional, general-purpose aromatic polycarbonate resins. Meanwhile, further improvements in mechanical properties such as tensile elongation and impact resistance at stress-concentrated areas are required for isosorbide-based polycarbonate resins. To address this issue, Patent Document 2 discloses a method for improving impact resistance by incorporating an elastomer into an isosorbide-based polycarbonate resin. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] British Patent No. 1079686 [Patent Document 2] Patent Publication No. 2021-25056 Summary of the Invention [Problem to be solved by the invention]

[0005] As disclosed in Patent Document 2, blending an elastomer as an impact modifier with an isosorbide-based polycarbonate resin is expected to provide excellent impact resistance. However, the use of an impact modifier almost always impairs properties such as heat resistance, weather resistance, scratch resistance, and transparency. In particular, the resin tends to discolor significantly when exposed to a high-temperature or humid-heat environment for a certain period of time, posing a problem in the long-term stability of its optical properties.

[0006] The present invention has been made in view of the above background, and aims to provide a thermoplastic resin composition that can give a high-quality molded article. More specifically, the present invention aims to provide a thermoplastic resin composition that can give a molded article having improved optical properties such as transparency and color tone and long-term stability of the optical properties, and a molded article using the same. [Means for solving the problem]

[0007] That is, the present invention has the following aspects.

[0008] [1] A polycarbonate resin (A) containing a structural unit represented by the following formula (1): a thermoplastic resin (B) other than the polycarbonate resin (A); and (C) a metal salt of a saturated or unsaturated fatty acid having 4 or more carbon atoms, a thermoplastic resin composition in which the content of the fatty acid metal salt (C) is 0.00001 part by mass or more and less than 0.02 part by mass per 100 parts by mass of the total of the polycarbonate resin (A) and the thermoplastic resin (B);

[0009] [ka]

[0010] [2] The thermoplastic resin composition according to [1], wherein the content of the polycarbonate resin (A) is 50 parts by mass or more and 99.9 parts by mass or less per 100 parts by mass of the total of the polycarbonate resin (A) and the thermoplastic resin (B). [3] The thermoplastic resin composition according to [1] or [2], wherein the metal of the fatty acid metal salt (C) is at least one selected from the group consisting of zinc, aluminum, calcium, magnesium, barium, sodium, and lithium.

[0011] [4] The thermoplastic resin composition according to any one of [1] to [3], wherein the thermoplastic resin (B) comprises at least one selected from the group consisting of polycarbonate resins, polyester resins, polyamide resins, vinyl resins, olefin resins, acrylic resins, and styrene resins. [5] The thermoplastic resin composition according to any one of [1] to [4], further comprising 0.010 to 2.0 parts by mass of a light stabilizer (D) relative to 100 parts by mass of the thermoplastic resin composition. [6] The thermoplastic resin composition according to any one of [1] to [5], wherein the thermoplastic resin (B) is a rubber-modified graft polymer.

[0012] [7] The thermoplastic resin composition according to [6], wherein the rubber-modified graft polymer is an elastomer having a core-shell structure. [8] The thermoplastic resin composition according to [7], wherein the elastomer is a copolymer containing a component derived from alkyl (meth)acrylate. [9] The thermoplastic resin composition according to any one of [1] to [5], wherein the thermoplastic resin (B) is a polyester resin.

[0013]

[10] The thermoplastic resin composition according to [9], wherein the polyester resin is an amorphous polyester.

[11] The thermoplastic resin composition according to

[10] , wherein the amorphous polyester is glycol-modified polyethylene terephthalate.

[12] A molded article formed from the thermoplastic resin composition according to any one of [1] to

[11] . [Effects of the Invention]

[0014] The thermoplastic resin composition can provide a molded article that is excellent in optical properties such as transparency and color tone, and in long-term stability of the optical properties. DETAILED DESCRIPTION OF THE INVENTION

[0015] The following describes embodiments of the present invention in detail. However, the following description of the configuration is merely an example (i.e., a representative example) of an embodiment of the present invention, and the present invention is not limited to the following content as long as it does not depart from the gist of the present invention. In this specification, the term "repeating structural unit" refers to a structural unit in which the same structure appears repeatedly in a resin and which constitutes the resin by linking together. For example, in the case of a polycarbonate resin, the term "repeating structural unit" also refers to a carbonyl group. Furthermore, the term "structural unit" refers to a partial structure that constitutes a resin, and refers to a specific partial structure contained in a repeating structural unit. For example, it refers to a partial structure sandwiched between adjacent linking groups in a resin, or a partial structure sandwiched between a polymerizable reactive group present at the terminal of a polymer and a linking group adjacent to the polymerizable reactive group. More specifically, in the case of a polycarbonate resin, a carbonyl group is the linking group, and a partial structure sandwiched between adjacent carbonyl groups is referred to as a structural unit. Furthermore, when the term "~" is used in this specification, it is used to include the numerical or physical values ​​written before and after it. Furthermore, numerical values ​​or physical values ​​described as upper and lower limits are intended to include those values. Furthermore, "parts by mass" and "parts by mass," "% by weight" and "% by mass" are essentially synonymous.

[0016] [Polycarbonate resin (A)] The thermoplastic resin composition contains a polycarbonate resin (A). The polycarbonate resin (A) contains a structural unit (hereinafter referred to as "structural unit (a1)") derived from a compound represented by the following formula (2) (hereinafter sometimes referred to as "compound (1)"). The structural unit (a1) is represented by the above formula (1). The polycarbonate resin (A) may be a homopolymer containing only the structural unit (a1) as a diol unit, or may be a copolymer containing the structural unit (a1) and another structural unit (a2) as a diol unit. From the viewpoints of increasing the molecular weight and further improving impact resistance, the polycarbonate resin (A) is preferably a copolymer.

[0017] [ka]

[0018] Examples of compound (1) include isosorbide, isomannide, and isoidet, which are stereoisomers, and these may be used alone or in combination of two or more. Among these, isosorbide, which is obtained by dehydration condensation of sorbitol produced from various starches that are abundant and easily available as plant-derived resources, is most preferred in terms of availability and ease of production, moldability, impact resistance, surface hardness, and carbon neutrality.

[0019] In the polycarbonate resin (A), the content of the structural unit (a1) is preferably 20 mol% or more, more preferably 30 mol% or more, and even more preferably 40 mol% or more, based on 100 mol% of all structural units derived from dihydroxy compounds. Also, it is preferably 95 mol% or less, more preferably 90 mol% or less, and even more preferably 80 mol% or less. By adjusting the content of the structural unit (a1) within this range, both the impact resistance and heat resistance of the polycarbonate resin can be improved in a balanced manner.

[0020] The polycarbonate resin (A) is preferably composed of a copolymer polycarbonate further comprising, as the structural unit (a2), a structural unit (a2-1) derived from one or more dihydroxy compounds selected from the group consisting of aliphatic dihydroxy compounds, alicyclic dihydroxy compounds, and ether group-containing dihydroxy compounds other than the dihydroxy compound represented by formula (2) (hereinafter, these may be referred to as "other dihydroxy compounds"). Because these dihydroxy compounds have flexible molecular structures, using these dihydroxy compounds as raw materials can improve the impact resistance of the resulting polycarbonate resin. Among these dihydroxy compounds, aliphatic dihydroxy compounds and alicyclic dihydroxy compounds are preferred, as they are highly effective in improving impact resistance, and alicyclic dihydroxy compounds are most preferred. Among alicyclic dihydroxy compounds, cyclobutanediol, cyclohexanedimethanol, and tricyclodecanedimethanol are particularly preferred from the viewpoint of further improving heat resistance and impact resistance. Specific examples of the aliphatic dihydroxy compound, the alicyclic dihydroxy compound, and the ether group-containing dihydroxy compound other than the dihydroxy compound represented by the formula (2) are as follows:

[0021] Examples of the aliphatic dihydroxy compound that can be used include the following: straight-chain aliphatic dihydroxy compounds such as ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, and 1,12-dodecanediol; and branched-chain aliphatic dihydroxy compounds such as 1,2-propanediol, 1,3-butanediol, 1,2-butanediol, neopentyl glycol, and hexylene glycol.

[0022] Examples of the alicyclic dihydroxy compound that can be used include the following dihydroxy compounds: dihydroxy compounds that are primary alcohols of alicyclic hydrocarbons, exemplified by dihydroxy compounds derived from terpene compounds such as 1,2-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, tricyclodecane dimethanol, pentacyclopentadecanedimethanol, 2,6-decalindimethanol, 1,5-decalindimethanol, 2,3-decalindimethanol, 2,3-norbornane dimethanol, 2,5-norbornane dimethanol, 1,3-adamantanedimethanol, and limonene; and dihydroxy compounds that are secondary or tertiary alcohols of alicyclic hydrocarbons, exemplified by 1,2-cyclohexanediol, 1,4-cyclohexanediol, 1,3-adamantanediol, hydrogenated bisphenol A, and 2,2,4,4-tetramethyl-1,3-cyclobutanediol.

[0023] Examples of ether group-containing dihydroxy compounds other than the dihydroxy compound represented by the formula (2) include oxyalkylene glycols and dihydroxy compounds containing an acetal ring. As the oxyalkylene glycol, for example, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, polypropylene glycol, etc. can be used.

[0024] As the dihydroxy compound containing an acetal ring, for example, spiro glycol represented by the following formula (3) or dioxane glycol represented by the following formula (4) can be used.

[0025] [ka]

[0026] [ka]

[0027] As the dihydroxy compound forming the structural unit (a2), among the dihydroxy compounds exemplified above, 1,4-cyclohexanedimethanol and tricyclodecane dimethanol are preferred, with 1,4-cyclohexanedimethanol being particularly preferred. By using 1,4-cyclohexanedimethanol, a high molecular weight polycarbonate resin can be easily obtained due to the good polymerization reactivity of 1,4-cyclohexanedimethanol, and a polycarbonate resin with extremely excellent mechanical properties such as impact resistance can be obtained.

[0028] In the polycarbonate resin (A), the content of structural units (a2) such as structural unit (a2-1) is preferably 5 mol% or more, more preferably 10 mol% or more, and even more preferably 20 mol% or more, based on 100 mol% of all structural units derived from dihydroxy compounds. It is also preferably 70 mol% or less, more preferably 60 mol% or less, and even more preferably 50 mol% or less. By adjusting the content of structural units (a2) within this range, both the impact resistance and heat resistance of the polycarbonate resin can be improved in a balanced manner.

[0029] The polycarbonate resin (A) may further contain structural units other than the structural units (a1) and (a2). Examples of other dihydroxy compounds that form such structural units include aromatic group-containing dihydroxy compounds. However, there is a significant difference in the polymerization reactivity between aromatic group-containing dihydroxy compounds and the dihydroxy compounds that form the structural units (a1) and (a2). If the former compounds remain unreacted, a high-molecular-weight polycarbonate resin cannot be obtained, which may result in reduced impact resistance. Therefore, from the perspective of further improving impact resistance and color tone, the content of structural units derived from aromatic group-containing dihydroxy compounds relative to 100 mol% of all structural units derived from dihydroxy compounds is preferably less than 50 mol%, more preferably 10 mol% or less, and even more preferably 5 mol% or less. Most preferably, the polycarbonate resin does not contain structural units derived from aromatic group-containing dihydroxy compounds.

[0030] As the dihydroxy compound containing an aromatic group, for example, the following dihydroxy compounds can be used, but dihydroxy compounds other than these can also be used. 2,2-bis(4-hydroxyphenyl)propane, 2,2-bis(3-methyl-4-hydroxyphenyl)propane, 2,2-bis(4-hydroxy-3,5-dimethylphenyl)propane, 2,2-bis(4-hydroxy-3,5-diethylphenyl)propane, 2,2-bis(4-hydroxy-(3-phenyl)phenyl)propane, 2,2-bis(4-hydroxy-(3,5-diphenyl)phenyl)propane, 2,2-bis(4-hydroxy-3,5-dibromophenyl)propane, bis(4-hydroxyphenyl)methane, 1,1-bis(4-hydroxyphenyl)ethane, 2,2-bis(4-hydroxyphenyl)butane, 2,2-bis(4-hydroxyphenyl)pentane, 1,1-bis(4-hydroxyphenyl)-1-phenylethane, bis(4-hydroxyphenyl)diphenylmethane, 1,1-bis(4-hydroxyphenyl)-2 aromatic bisphenol compounds such as -ethylhexane, 1,1-bis(4-hydroxyphenyl)decane, bis(4-hydroxy-3-nitrophenyl)methane, 3,3-bis(4-hydroxyphenyl)pentane, 1,3-bis(2-(4-hydroxyphenyl)-2-propyl)benzene, 1,3-bis(2-(4-hydroxyphenyl)-2-propyl)benzene, 2,2-bis(4-hydroxyphenyl)hexafluoropropane, 1,1-bis(4-hydroxyphenyl)cyclohexane, bis(4-hydroxyphenyl)sulfone, 2,4'-dihydroxydiphenyl sulfone, bis(4-hydroxyphenyl)sulfide, bis(4-hydroxy-3-methylphenyl)sulfide, bis(4-hydroxyphenyl)disulfide, 4,4'-dihydroxydiphenyl ether, and 4,4'-dihydroxy-3,3'-dichlorodiphenyl ether;Dihydroxy compounds having an ether group bonded to an aromatic group, such as 2,2-bis(4-(2-hydroxyethoxy)phenyl)propane, 2,2-bis(4-(2-hydroxypropoxy)phenyl)propane, 1,3-bis(2-hydroxyethoxy)benzene, 4,4'-bis(2-hydroxyethoxy)biphenyl, and bis(4-(2-hydroxyethoxy)phenyl)sulfone; 9,9-bis(4-(2-hydroxyethoxy)phenyl)fluorene, 9,9-bis(4-hydroxyphenyl)fluorene, 9,9-bis(4-hydroxy-3-methylphenyl)fluorene, 9,9-bis(4-(2-hydroxypropoxy)phenyl)fluorene, 9,9-bis(4-(2-hydroxyethoxy)-3-methylphenyl)fluorene, and 9,9-bis(4-(2-hydroxypropoxy)-3-methylphenyl)fluorene; Dihydroxy compounds having a fluorene ring, such as fluorene, 9,9-bis(4-(2-hydroxyethoxy)-3-isopropylphenyl)fluorene, 9,9-bis(4-(2-hydroxyethoxy)-3-isobutylphenyl)fluorene, 9,9-bis(4-(2-hydroxyethoxy)-3-tert-butylphenyl)fluorene, 9,9-bis(4-(2-hydroxyethoxy)-3-cyclohexylphenyl)fluorene, 9,9-bis(4-(2-hydroxyethoxy)-3-phenylphenyl)fluorene, 9,9-bis(4-(2-hydroxyethoxy)-3,5-dimethylphenyl)fluorene, 9,9-bis(4-(2-hydroxyethoxy)-3-tert-butyl-6-methylphenyl)fluorene, and 9,9-bis(4-(3-hydroxy-2,2-dimethylpropoxy)phenyl)fluorene;

[0031] The other dihydroxy compounds can be appropriately selected depending on the properties required for the polycarbonate resin. The other dihydroxy compounds may be used alone or in combination. The use of the other dihydroxy compounds in combination with compound (1) can improve the flexibility and mechanical properties of the polycarbonate resin, as well as the moldability.

[0032] The dihydroxy compound used as a raw material for polycarbonate resin (A) may contain a stabilizer such as a reducing agent, antioxidant, oxygen scavenger, light stabilizer, antacid, pH stabilizer, or heat stabilizer. Compound (1) in particular has the property of being easily degraded under acidic conditions. Therefore, the use of a basic stabilizer in the synthesis process of the polycarbonate resin can suppress the degradation of compound (1). This can further improve the quality of the resulting polycarbonate resin composition.

[0033] Examples of the basic stabilizer that can be used include the following compounds: hydroxides, carbonates, phosphates, phosphites, hypophosphites, borates, and fatty acid salts of metals of Group 1 or 2 of the long-form periodic table (Nomenclature of Inorganic Chemistry IUPAC Recommendations 2005); tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, trimethylethylammonium hydroxide, trimethylbenzylammonium hydroxide, trimethylphenylammonium hydroxide, triethylmethylammonium hydroxide, triethylbenzylammonium hydroxide, triethylphenylammonium hydroxide, tributylbenzylammonium hydroxide, tributylphenylammonium hydroxide, tetraphenylammonium hydroxide, benzyltriphenylammonium hydroxide, methyltriphenylammonium hydroxide, and butyltriphenylammonium hydroxide. basic ammonium compounds such as phenylammonium hydroxide; amine compounds such as diethylamine, dibutylamine, triethylamine, morpholine, N-methylmorpholine, pyrrolidine, piperidine, 3-amino-1-propanol, ethylenediamine, N-methyldiethanolamine, diethylethanolamine, diethanolamine, triethanolamine, 4-aminopyridine, 2-aminopyridine, N,N-dimethyl-4-aminopyridine, 4-diethylaminopyridine, 2-hydroxypyridine, 2-methoxypyridine, 4-methoxypyridine, 2-dimethylaminoimidazole, 2-methoxyimidazole, imidazole, 2-mercaptoimidazole, 2-methylimidazole, and aminoquinoline; and hindered amine compounds such as di-(tert-butyl)amine and 2,2,6,6-tetramethylpiperidine.

[0034] The content of the basic stabilizer in the dihydroxy compound is not particularly limited. However, since compound (1) is unstable in an acidic state, it is preferable to set the content of the basic stabilizer so that the pH of an aqueous solution of the dihydroxy compound containing the basic stabilizer is around 7.

[0035] The content of the basic stabilizer relative to compound (1) is preferably 0.0001 to 1% by weight. In this case, the effect of preventing the deterioration of compound (1) is sufficiently obtained. From the viewpoint of further enhancing this effect, the content of the basic stabilizer is more preferably 0.001 to 0.1% by weight.

[0036] As the carbonic acid diester used as a raw material for the polycarbonate resin (A), a compound represented by the following formula (5) can usually be used: One of these carbonic acid diesters may be used alone, or two or more of them may be used in combination.

[0037] [ka]

[0038] In the formula (5), A 1 and A 2 are each independently a substituted or unsubstituted aliphatic hydrocarbon group having 1 to 18 carbon atoms or a substituted or unsubstituted aromatic hydrocarbon group, and A 1 and A 2 A may be the same or different. 1 and A 2 is preferably a substituted or unsubstituted aromatic hydrocarbon group, more preferably an unsubstituted aromatic hydrocarbon group.

[0039] Examples of the carbonate diester represented by formula (5) that can be used include diphenyl carbonate (DPC), substituted diphenyl carbonates such as ditolyl carbonate, dimethyl carbonate, diethyl carbonate, and di-tert-butyl carbonate. Among these carbonate diesters, it is preferable to use diphenyl carbonate or a substituted diphenyl carbonate, and it is particularly preferable to use diphenyl carbonate. Note that the carbonate diester may contain impurities such as chloride ions, which may inhibit the polycondensation reaction or deteriorate the color tone of the resulting polycarbonate resin. Therefore, it is preferable to use a diester purified by distillation or the like, as necessary.

[0040] The polycarbonate resin (A) can be synthesized by polycondensing the dihydroxy compound and the carbonic acid diester through a transesterification reaction. More specifically, the polycarbonate resin (A) can be obtained by removing the monohydroxy compound and other by-products produced in the transesterification reaction from the system during the polycondensation.

[0041] The transesterification reaction proceeds in the presence of a transesterification catalyst (hereinafter, the transesterification catalyst will be referred to as a "polymerization catalyst.") The type of polymerization catalyst can have a significant effect on the reaction rate of the transesterification reaction and the quality of the resulting polycarbonate resin.

[0042] The polymerization catalyst is not limited as long as it can provide the resulting polycarbonate resin (A) with satisfactory transparency, color tone, heat resistance, weather resistance, and mechanical strength. Examples of the polymerization catalyst that can be used include metal compounds of Group I or Group II (hereinafter simply referred to as "Group 1" and "Group 2") in the long-form periodic table, as well as basic compounds such as basic boron compounds, basic phosphorus compounds, basic ammonium compounds, and amine compounds, with Group 1 metal compounds and / or Group 2 metal compounds being preferred.

[0043] Examples of the Group 1 metal compound that can be used include the following compounds: sodium hydroxide, potassium hydroxide, lithium hydroxide, cesium hydroxide, sodium hydrogen carbonate, potassium hydrogen carbonate, lithium hydrogen carbonate, cesium hydrogen carbonate, sodium carbonate, potassium carbonate, lithium carbonate, cesium carbonate, sodium acetate, potassium acetate, lithium acetate, cesium acetate, sodium stearate, potassium stearate, lithium stearate, cesium stearate, sodium borohydride, potassium borohydride, lithium borohydride, cesium borohydride, sodium phenylborohydride, and boron phenylide. Potassium, lithium phenylborate, cesium phenylborate, sodium benzoate, potassium benzoate, lithium benzoate, cesium benzoate, disodium hydrogen phosphate, dipotassium hydrogen phosphate, dilithium hydrogen phosphate, dicesium hydrogen phosphate, disodium phenylphosphate, dipotassium phenylphosphate, dilithium phenylphosphate, dicesium phenylphosphate, sodium, potassium, lithium, and cesium alcoholates and phenolates, disodium, dipotassium, dilithium, and dicesium salts of bisphenol A, etc. As the Group 1 metal compound, a lithium compound is preferred from the viewpoint of polymerization activity and the color tone of the resulting polycarbonate resin (A).

[0044] Examples of the Group 2 metal compound that can be used include the following compounds: calcium hydroxide, barium hydroxide, magnesium hydroxide, strontium hydroxide, calcium hydrogen carbonate, barium hydrogen carbonate, magnesium hydrogen carbonate, strontium hydrogen carbonate, calcium carbonate, barium carbonate, magnesium carbonate, strontium carbonate, calcium acetate, barium acetate, magnesium acetate, strontium acetate, calcium stearate, barium stearate, magnesium stearate, and strontium stearate. As the Group 2 metal compound, a magnesium compound, a calcium compound, or a barium compound is preferred, and from the viewpoints of polymerization activity and the color tone of the resulting polycarbonate resin (A), a magnesium compound and / or a calcium compound is more preferred, and a calcium compound is most preferred.

[0045] It is also possible to use a basic compound such as a basic boron compound, a basic phosphorus compound, a basic ammonium compound, or an amine compound in combination with the Group 1 metal compound and / or Group 2 metal compound as an auxiliary. However, it is particularly preferable to use only the Group 1 metal compound and / or Group 2 metal compound.

[0046] Examples of the basic boron compound that can be used include the following compounds: salts of tetramethyl boron, tetraethyl boron, tetrapropyl boron, tetrabutyl boron, trimethylethyl boron, trimethylbenzyl boron, trimethylphenyl boron, triethylmethyl boron, triethylbenzyl boron, triethylphenyl boron, tributylbenzyl boron, tributylphenyl boron, tetraphenyl boron, benzyltriphenyl boron, and methyltriphenyl boron. Also included are sodium, potassium, lithium, calcium, barium, magnesium, and strontium salts of butyltriphenyl boron and the like.

[0047] As the basic phosphorus compound, for example, the following compounds can be used: triethylphosphine, tri-n-propylphosphine, triisopropylphosphine, tri-n-butylphosphine, triphenylphosphine, tributylphosphine, and quaternary phosphonium salts.

[0048] Examples of the basic ammonium compound that can be used include the following compounds: tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, trimethylethylammonium hydroxide, trimethylbenzylammonium hydroxide, trimethylphenylammonium hydroxide, triethylmethylammonium hydroxide, triethylbenzylammonium hydroxide, triethylphenylammonium hydroxide, tributylbenzylammonium hydroxide, tributylphenylammonium hydroxide, tetraphenylammonium hydroxide, benzyltriphenylammonium hydroxide, methyltriphenylammonium hydroxide, and butyltriphenylammonium hydroxide.

[0049] Examples of the amine compound that can be used include the following compounds: 4-aminopyridine, 2-aminopyridine, N,N-dimethyl-4-aminopyridine, 4-diethylaminopyridine, 2-hydroxypyridine, 2-methoxypyridine, 4-methoxypyridine, 2-dimethylaminoimidazole, 2-methoxyimidazole, imidazole, 2-mercaptoimidazole, 2-methylimidazole, aminoquinoline, and guanidine.

[0050] The amount of the polymerization catalyst used is preferably 0.1 to 300 μmol, more preferably 0.5 to 100 μmol, and particularly preferably 1 to 50 μmol, per mol of the total dihydroxy compounds used in the reaction.

[0051] When a compound containing at least one metal selected from the group consisting of Group 2 metals in the long periodic table and lithium is used as the polymerization catalyst, particularly when a magnesium compound and / or a calcium compound is used, the amount of the polymerization catalyst used is preferably 0.1 μmol or more, more preferably 0.3 μmol or more, and particularly preferably 0.5 μmol or more, in terms of the metal atomic weight of the compound containing the metal, per mol of the total dihydroxy compounds used in the reaction. The upper limit is preferably 10 μmol or less, more preferably 5 μmol or less, and particularly preferably 3 μmol or less.

[0052] By adjusting the amount of polymerization catalyst used within the above range, the polymerization rate can be increased, making it possible to obtain a polycarbonate resin (A) of the desired molecular weight without necessarily increasing the polymerization temperature, thereby suppressing deterioration in the color tone of the polycarbonate resin (A). Furthermore, it is possible to prevent unreacted raw materials from volatilizing during the polymerization, which would disrupt the molar ratio of the dihydroxy compound to the carbonate diester, thereby more reliably obtaining a resin of the desired molecular weight. Furthermore, it is possible to suppress the occurrence of side reactions, thereby further preventing deterioration in the color tone of the polycarbonate resin (A) or discoloration during molding.

[0053] Considering the adverse effects of sodium, potassium, or cesium, among the Group 1 metals, on the color tone of the polycarbonate resin (A), and the adverse effects of iron on the color tone of the polycarbonate resin (A), the total content of sodium, potassium, cesium, and iron in the polycarbonate resin (A) is preferably 1 ppm by weight or less. In this case, deterioration of the color tone of the polycarbonate resin (A) can be further prevented, and the color tone of the polycarbonate resin (A) can be further improved. From the same perspective, the total content of sodium, potassium, cesium, and iron in the polycarbonate resin (A) is more preferably 0.5 ppm by weight or less. Note that these metals may be mixed in not only from the catalyst used but also from raw materials or the reaction equipment. Regardless of their origin, the total amount of compounds of these metals in the polycarbonate resin (A) is preferably within the above-mentioned range as the total content of sodium, potassium, cesium, and iron.

[0054] <Physical properties of polycarbonate resin (A)> The molecular weight of the polycarbonate resin (A) can be expressed by reduced viscosity, with a higher reduced viscosity indicating a higher molecular weight. The reduced viscosity is preferably 0.30 dL / g or higher, more preferably 0.35 dL / g or higher. On the other hand, the reduced viscosity is preferably 1.20 dL / g or lower, more preferably 1.00 dL / g or lower, and even more preferably 0.80 dL / g or lower. By adjusting the reduced viscosity within the above range, fluidity during molding can be improved, resulting in improved productivity and moldability. Therefore, molded products with complex shapes can be produced with high productivity, making them suitable for electrical and electronic equipment components, automotive interior and exterior components, and the like. The reduced viscosity of the polycarbonate resin (A) is measured using an Ubbelohde viscometer at a temperature of 20.0°C ± 0.1°C, with the polycarbonate resin concentration precisely adjusted to 0.6 g / dL using methylene chloride as a solvent. In the examples described later, the reduced viscosity of the produced polycarbonate resin (A) is measured by this method.

[0055] The melt viscosity of the polycarbonate resin (A) is preferably 400 Pa·s or more and 3000 Pa·s or less. If the melt viscosity of the polycarbonate resin (A) is within this range, the resulting molded article can be prevented from becoming brittle and mechanical properties can be further improved. Furthermore, in this case, the flowability during molding processing can be improved, preventing damage to the appearance of the molded article and deterioration of dimensional accuracy. Furthermore, in this case, coloration and foaming caused by an increase in resin temperature due to shear heating can be further prevented. From the same perspective, the melt viscosity of the polycarbonate resin (A) is more preferably 600 Pa·s or more and 2500 Pa·s or less, and even more preferably 800 Pa·s or more and 2000 Pa·s or less. The melt viscosity of the polycarbonate resin (A) is measured using a capillary rheometer (manufactured by Toyo Seiki Seisakusho, Ltd.) at a temperature of 240°C and a shear rate of 91.2 sec. -1 In the examples described later, the melt viscosity of the produced polycarbonate resin (A) was measured by this method.

[0056] The glass transition temperature of the polycarbonate resin (A) is preferably 70°C or higher. A glass transition temperature of 70°C or higher is preferable because it allows for a well-balanced improvement in heat resistance and content of biogenic substances. From the same viewpoint, the glass transition temperature of the polycarbonate resin (A) is more preferably 80°C or higher, even more preferably 90°C or higher, and particularly preferably 100°C or higher. On the other hand, the glass transition temperature of the polycarbonate resin (A) is preferably 150°C or lower. If the glass transition temperature is 150°C or lower, the melt viscosity can be reduced by the above-mentioned melt polymerization, and a polymer with a sufficient molecular weight can be obtained. Furthermore, when an attempt is made to increase the molecular weight by increasing the polymerization temperature and reducing the melt viscosity, the structural unit (a1) may have insufficient heat resistance, which may result in the polymer being easily discolored. From the viewpoint of a better balance between improving the molecular weight and preventing discoloration, the glass transition temperature of the polycarbonate resin (A) is more preferably 150°C or lower, even more preferably 140°C or lower, and particularly preferably 130°C or lower.

[0057] The polycarbonate resin composition of the present invention may contain one type of resin alone as the polycarbonate resin (A), or may contain a mixture of two or more resins that differ in the type of structural unit (a2) derived from other dihydroxy compounds, copolymerization ratio, physical properties, etc.

[0058] <Synthesis of polycarbonate resin (A)> The polycarbonate resin (A) can be obtained by polycondensing a dihydroxy compound, such as compound (1), used as a raw material with a carbonic acid diester through transesterification in the presence of a polymerization catalyst.

[0059] The dihydroxy compound and carbonate diester raw materials are preferably mixed uniformly before the transesterification reaction. The mixing temperature is usually 80°C or higher, preferably 90°C or higher, and usually 250°C or lower, preferably 200°C or lower, and more preferably 150°C or lower, with 100°C or higher and 120°C or lower being preferred. In this case, the dissolution rate can be increased, the solubility can be sufficiently improved, and problems such as solidification can be sufficiently avoided. Furthermore, in this case, thermal degradation of the dihydroxy compound can be sufficiently suppressed, resulting in a more favorable color tone of the resulting polycarbonate resin (A) and improved weather resistance.

[0060] The operation of mixing the raw material dihydroxy compound and carbonic acid diester is preferably carried out in an atmosphere with an oxygen concentration of 10 vol% or less, more preferably 0.0001 to 10 vol%, even more preferably 0.0001 to 5 vol%, and particularly preferably 0.0001 to 1 vol%, which can improve the color tone and increase the reactivity.

[0061] To obtain polycarbonate resin (A), it is preferable to use a carbonic acid diester in a molar ratio of 0.90 to 1.20 relative to the total dihydroxy compounds used in the reaction. In this case, an increase in the number of terminal hydroxy groups in the polycarbonate resin can be suppressed, thereby improving the thermal stability of the polymer. This can further prevent coloration during molding and increase the rate of the transesterification reaction. It also makes it possible to more reliably obtain a desired high molecular weight polymer. Furthermore, by adjusting the amount of carbonic acid diester used within the above range, a decrease in the rate of the transesterification reaction can be suppressed, enabling more reliable production of polycarbonate resin (A) with the desired molecular weight. Furthermore, this can suppress an increase in thermal history during the reaction, thereby further improving the color tone and weather resistance of the polycarbonate resin (A). Furthermore, this can reduce the amount of residual carbonic acid diester in the polycarbonate resin (A), thereby avoiding or mitigating the generation of stains and odors during molding. From the same viewpoints as above, it is more preferable that the amount of carbonic acid diester used relative to the total dihydroxy compounds is 0.95 to 1.10 in molar ratio.

[0062] The polycondensation of a dihydroxy compound and a carbonate diester is carried out in multiple stages using multiple reactors in the presence of the above-mentioned catalyst. The reaction may be carried out in a batchwise manner, a continuous manner, or a combination of a batchwise manner and a continuous manner, but it is preferable to adopt a continuous manner, which can produce a polycarbonate resin (A) with less thermal history and is therefore excellent in productivity.

[0063] From the viewpoint of controlling the polymerization rate and the quality of the resulting polycarbonate resin (A), it is important to appropriately select the jacket temperature, internal temperature, and pressure in the reaction system according to the reaction stage. Specifically, it is preferable to obtain a prepolymer at a relatively low temperature and low vacuum in the early stage of the polycondensation reaction, and to increase the molecular weight to a predetermined value at a relatively high temperature and high vacuum in the later stage of the reaction. In this case, distillation of unreacted monomers is suppressed, and it becomes easier to adjust the molar ratio of the dihydroxy compound to the carbonate diester to the desired ratio. As a result, a decrease in the polymerization rate can be suppressed. Furthermore, it becomes possible to more reliably obtain a polymer with the desired molecular weight and terminal groups.

[0064] Furthermore, the polymerization rate in a polycondensation reaction is controlled by the balance between hydroxyl and carbonate terminal groups. Therefore, if the balance of terminal groups fluctuates due to the distillation of unreacted monomers, it becomes difficult to maintain a constant polymerization rate, which can lead to significant fluctuations in the molecular weight of the resulting resin. Because the molecular weight of a resin correlates with its melt viscosity, fluctuations in melt viscosity can occur during melt processing of the resulting resin, making it difficult to maintain consistent molded product quality. This problem is particularly likely to occur when polycondensation reactions are performed continuously.

[0065] The use of a reflux condenser in a polymerization reactor is effective in suppressing the amount of unreacted monomer distilled off, and is particularly effective in the early stages of the reaction when a large amount of unreacted monomer is present. The temperature of the refrigerant introduced into the reflux condenser can be appropriately selected depending on the monomer used. Typically, the temperature of the refrigerant introduced into the reflux condenser at the inlet is 45 to 180°C, preferably 80 to 150°C, and particularly preferably 100 to 130°C. By adjusting the refrigerant temperature within these ranges, the reflux amount can be sufficiently increased, its effects can be fully achieved, and the efficiency of distillation of the monohydroxy compound to be distilled off can be sufficiently improved. As a result, a decrease in the reaction rate can be prevented, and coloration of the resulting resin can be further prevented. Examples of refrigerants that can be used include hot water, steam, and heat transfer oil, with steam and heat transfer oil being preferred.

[0066] In order to maintain an appropriate polymerization rate, suppress distillation of monomers, and improve the color tone of the resulting polycarbonate resin (A), it is important to select the type and amount of the polymerization catalyst described above.

[0067] The polycarbonate resin (A) is usually produced through two or more steps using a polymerization catalyst. The polycondensation reaction may be carried out in two or more steps using one polycondensation reactor, with conditions sequentially changed, but from the viewpoint of production efficiency, it is preferable to carry out the reaction in multiple steps using multiple reactors, with conditions changed for each step.

[0068] From the viewpoint of efficiently carrying out the polycondensation reaction, in the early stage of the reaction when the reaction solution contains a large amount of monomer, it is important to maintain the required polymerization rate while suppressing the evaporation of the monomer. Furthermore, in the later stage of the reaction, it is important to shift the equilibrium toward the polycondensation reaction by sufficiently distilling off the by-product monohydroxy compound. Therefore, the reaction conditions suitable for the early stage of the reaction are usually different from those suitable for the later stage of the reaction. Therefore, by using multiple reactors arranged in series, the respective conditions can be easily changed, thereby improving production efficiency.

[0069] As described above, the number of polymerization reactors used in the production of the polycarbonate resin (A) may be at least two, but from the viewpoint of production efficiency, the number is three or more, preferably 3 to 5, and particularly preferably 4. When there are two or more polymerization reactors, a plurality of reaction stages under different conditions may be carried out in each polymerization reactor, or the temperature and pressure may be changed continuously.

[0070] The polymerization catalyst can be added to a raw material preparation tank or a raw material storage tank, or can be added directly to a polymerization reactor. From the viewpoint of supply stability and control of the polycondensation reaction, it is preferable to install a catalyst supply line in the raw material line before supplying the raw materials to the polymerization reactor, and supply the polymerization catalyst in the form of an aqueous solution.

[0071] Adjusting the temperature of the polycondensation reaction can improve productivity and prevent the product from being subjected to increased heat history. Furthermore, it is possible to further prevent volatilization of the monomer and decomposition or discoloration of the polycarbonate resin (A). Specifically, the following reaction conditions can be adopted for the first-stage reaction. The maximum internal temperature of the polymerization reactor is set within the range of usually 150 to 250°C, preferably 160 to 240°C, and more preferably 170 to 230°C. The pressure of the polymerization reactor (hereinafter, "pressure" refers to absolute pressure) is set within the range of usually 1 to 110 kPa, preferably 5 to 70 kPa, and more preferably 7 to 30 kPa. The reaction time is set within the range of usually 0.1 to 10 hours, preferably 0.5 to 3 hours. The first-stage reaction is preferably carried out while distilling off the generated monohydroxy compound from the reaction system.

[0072] From the second stage onwards, it is preferable to gradually reduce the pressure of the reaction system from the pressure of the first stage, and ultimately reduce the pressure (absolute pressure) of the reaction system to 1 kPa or less while continuously removing the generated monohydroxy compound from the reaction system. The maximum internal temperature of the polymerization reactor is usually set in the range of 200 to 260°C, preferably 210 to 250°C. The reaction time is usually set in the range of 0.1 to 10 hours, preferably 0.3 to 6 hours, and particularly preferably 0.5 to 3 hours.

[0073] From the viewpoint of further suppressing discoloration and thermal degradation of the polycarbonate resin (A) and obtaining a polycarbonate resin (A) with a better color tone, it is preferable to set the maximum internal temperature of the polymerization reactor, which has the highest internal temperature among all reaction stages, to 210 to 240° C. Furthermore, in order to prevent a decrease in the polymerization rate in the latter half of the reaction and to minimize deterioration due to thermal history, it is preferable to use a horizontal reactor, which has excellent plug flow properties and interface renewal properties, in the final stage of the polycondensation reaction.

[0074] In continuous polymerization, in order to control the molecular weight of the polycarbonate resin (A) finally obtained at a constant level, it is preferable to adjust the polymerization rate as necessary. In this case, a method with good operability is to adjust the pressure in the polymerization reactor in the final stage.

[0075] Furthermore, as mentioned above, the polymerization rate varies depending on the ratio of hydroxyl group terminals to carbonate group terminals. Therefore, by deliberately reducing one of the terminal groups to suppress the polymerization rate and maintaining a high vacuum in the final-stage polymerization reactor, the amount of remaining low-molecular-weight components in the resin, including monohydroxy compounds, can be reduced. However, in this case, if the amount of one terminal is too small, even a slight change in the terminal group balance can drastically reduce the reactivity, and the molecular weight of the resulting polycarbonate resin may not reach the desired molecular weight. To avoid this problem, it is preferable that the polycarbonate resin (A) obtained in the final-stage polymerization reactor contain at least 10 mol / ton of both hydroxyl group terminals and carbonate group terminals. On the other hand, if both terminal groups are too large, the polymerization rate will be too fast and the molecular weight will be too high, so it is preferable that the amount of one terminal group be 60 mol / ton or less.

[0076] In this way, by adjusting the amount of terminal groups and the pressure of the final-stage polymerization reactor within preferred ranges, the amount of monohydroxy compounds remaining in the resin at the outlet of the polymerization reactor can be reduced. The amount of monohydroxy compounds remaining in the resin at the outlet of the polymerization reactor is preferably 2000 ppm by weight or less, more preferably 1500 ppm by weight or less, and even more preferably 1000 ppm by weight or less. By reducing the content of monohydroxy compounds at the outlet of the polymerization reactor in this way, volatilization of monohydroxy compounds and the like can be easily carried out in a subsequent step.

[0077] Although it is preferable that the amount of the remaining monohydroxy compound is small, in order to reduce it to less than 100 ppm by weight, it is necessary to extremely reduce the amount of one of the terminal groups and adopt operating conditions such as maintaining the pressure of the polymerization reactor at a high vacuum. In this case, as mentioned above, it becomes difficult to maintain the molecular weight of the obtained polycarbonate resin at a constant level, so the amount is usually 100 ppm by weight or more, preferably 150 ppm by weight or more.

[0078] From the viewpoint of effective resource utilization, it is preferable to reuse the by-produced monohydroxy compound as a raw material for other compounds after purifying it as necessary. For example, when the monohydroxy compound is phenol, it can be used as a raw material for diphenyl carbonate, bisphenol A, etc.

[0079] The polycarbonate resin (A) preferably contains a catalyst deactivator. The catalyst deactivator is not particularly limited as long as it is an acidic substance that has the function of deactivating the polymerization catalyst, but examples thereof include phosphoric acid, trimethyl phosphate, triethyl phosphate, phosphorous acid, phosphonium salts such as octylsulfonate tetrabutylphosphonium salt, benzenesulfonate tetramethylphosphonium salt, benzenesulfonate tetrabutylphosphonium salt, dodecylbenzenesulfonate tetrabutylphosphonium salt, and p-toluenesulfonate tetrabutylphosphonium salt; ammonium salts such as decylsulfonate tetramethylammonium salt, and dodecylbenzenesulfonate tetrabutylammonium salt; and alkyl esters such as benzenesulfonate methyl, benzenesulfonate butyl, p-toluenesulfonate methyl, p-toluenesulfonate butyl, and hexadecylsulfonate ethyl.

[0080] The catalyst deactivator preferably contains a phosphorus-based compound (hereinafter referred to as the "specific phosphorus-based compound") containing either the partial structure represented by the following formula (6) or the following formula (7). The specific phosphorus-based compound can be added after the polycondensation reaction is completed, i.e., during the kneading process, pelletization process, etc., to deactivate the polymerization catalyst and suppress the unwanted progression of the polycondensation reaction thereafter. As a result, the progression of polycondensation when the polycarbonate resin (A) is heated in a molding process, etc., can be suppressed, and thus the elimination of the monohydroxy compound can be suppressed. Furthermore, by deactivating the polymerization catalyst, discoloration of the polycarbonate resin (A) at high temperatures can be further suppressed.

[0081] [ka]

[0082] [ka]

[0083] The specific phosphorus-based compound containing the partial structure represented by formula (6) or (7) may be phosphoric acid, phosphorous acid, phosphonic acid, hypophosphorous acid, polyphosphoric acid, phosphonate ester, acidic phosphate ester, etc. Among the specific phosphorus-based compounds, phosphorous acid, phosphonic acid, and phosphonate ester are more effective in deactivating the catalyst and inhibiting coloration, and phosphorous acid is particularly preferred.

[0084] As the phosphonic acid, for example, the following compounds can be used: phosphonic acid (phosphorous acid), methylphosphonic acid, ethylphosphonic acid, vinylphosphonic acid, decylphosphonic acid, phenylphosphonic acid, benzylphosphonic acid, aminomethylphosphonic acid, methylenediphosphonic acid, 1-hydroxyethane-1,1-diphosphonic acid, 4-methoxyphenylphosphonic acid, nitrilotris(methylenephosphonic acid), propylphosphonic anhydride, etc.

[0085] As the phosphonate ester, for example, the following compounds can be used: dimethyl phosphonate, diethyl phosphonate, bis(2-ethylhexyl) phosphonate, dilauryl phosphonate, dioleyl phosphonate, diphenyl phosphonate, dibenzyl phosphonate, dimethyl methylphosphonate, diphenyl methylphosphonate, diethyl ethylphosphonate, diethyl benzylphosphonate, dimethyl phenylphosphonate, diethyl phenylphosphonate, dipropyl phenylphosphonate, diethyl (methoxymethyl)phosphonate, diethyl vinylphosphonate, hydroxymethylphosphonic acid, diethyl phosphonate, dimethyl (2-hydroxyethyl)phosphonate, diethyl p-methylbenzylphosphonate, diethyl phosphonoacetic acid, ethyl diethylphosphonoacetate, tert-butyl diethylphosphonoacetate, diethyl (4-chlorobenzyl)phosphonate, diethyl cyanophosphonate, diethyl cyanomethylphosphonate, diethyl 3,5-di-tert-butyl-4-hydroxybenzylphosphonate, diethyl phosphonoacetaldehyde diethyl acetal, diethyl (methylthiomethyl)phosphonate, and the like.

[0086] Examples of acidic phosphate esters that can be used include the following compounds: phosphate diesters such as dimethyl phosphate, diethyl phosphate, divinyl phosphate, dipropyl phosphate, dibutyl phosphate, bis(butoxyethyl) phosphate, bis(2-ethylhexyl) phosphate, diisotridecyl phosphate, dioleyl phosphate, distearyl phosphate, diphenyl phosphate, and dibenzyl phosphate, or mixtures of diesters and monoesters, diethyl chlorophosphate, and zinc stearyl phosphate.

[0087] The specific phosphorus-based compounds may be used singly or in any combination and ratio of two or more.

[0088] The content of the specific phosphorus compound in the polycarbonate resin (A) is preferably 0.1 ppm by weight or more and 5 ppm by weight or less in terms of phosphorus atoms. In this case, the specific phosphorus compound can sufficiently suppress catalyst deactivation and coloration. In addition, in this case, coloration of the polycarbonate resin (A) can be further prevented, particularly in durability tests under high temperature and high humidity.

[0089] Furthermore, by adjusting the content of the specific phosphorus-based compound according to the amount of the polymerization catalyst, the effect of suppressing catalyst deactivation and coloration can be more reliably obtained. The content of the specific phosphorus-based compound is preferably 0.5 to 5 times the molar amount of phosphorus atoms per 1 mol of metal atoms in the polymerization catalyst, more preferably 0.7 to 4 times the molar amount, and particularly preferably 0.8 to 3 times the molar amount of phosphorus atoms per 1 mol of metal atoms in the polymerization catalyst.

[0090] [Thermoplastic resin (B)] The polycarbonate resin composition contains a thermoplastic resin (B). The thermoplastic resin (B) is a thermoplastic resin other than the polycarbonate resin (A). The content of the polycarbonate resin (A) relative to 100 parts by mass of the total of the polycarbonate resin (A) and the thermoplastic resin (B) is preferably 50 parts by mass or more and 99.9 parts by mass or less. In this case, the thermoplastic resin composition can provide a molded article with excellent mechanical properties, and the molded article has excellent mechanical properties. Furthermore, the desired modification effect can be obtained by the thermoplastic resin (B). From the viewpoint of the balance of these effects, the content of the polycarbonate resin (A) relative to 100 parts by mass of the total of the polycarbonate resin (A) and the thermoplastic resin (B) is preferably 50 parts by mass or more, more preferably 60 parts by mass or more, and even more preferably 70 parts by mass or more. In the more preferred embodiments, it may be 85 parts by mass or more, 90 parts by mass or more, 92.5 parts by mass or more, or 95 parts by mass or more. Furthermore, from the viewpoint of maintaining good heat resistance and weather resistance, the content of the polycarbonate resin (A) relative to 100 parts by mass of the total of the polycarbonate resin (A) and the thermoplastic resin (B) is preferably 99.5 parts by mass or less, more preferably 99 parts by mass or less, even more preferably 98 parts by mass or less, and particularly preferably 97 parts by mass or less, and in the particularly preferred embodiment, it may be 95 parts by mass or less, 90 parts by mass or less, 85 parts by mass or less, 80 parts by mass or less, 75 parts by mass or less, or 70 parts by mass or less.

[0091] The thermoplastic resin (B) preferably contains at least one selected from the group consisting of polycarbonate resins other than the polycarbonate resin (A), polyester resins, polyamide resins, vinyl resins, olefin resins, acrylic resins, and styrene resins. Polycarbonate resins other than the polycarbonate resin (A) will hereinafter be referred to as "polycarbonate resin (B)" where appropriate.

[0092] Various known polycarbonate resins can be used as the polycarbonate resin (B). The polycarbonate resin (B) may be used singly or in combination of two or more. The polycarbonate resin (B) may be a homopolymer containing, as diol units, structural units derived from an aliphatic dihydroxy compound, an alicyclic dihydroxy compound, an ether group-containing dihydroxy compound, or an aromatic group-containing dihydroxy compound, or a copolymer containing two or more structural units as diol units. The polycarbonate resin (B) can be produced by a solvent method, i.e., by reacting a dihydric phenol with a carbonate precursor such as phosgene in a solvent such as methylene chloride in the presence of a known acid acceptor and molecular weight modifier. Alternatively, the polycarbonate resin (B) can be produced by the transesterification reaction of a dihydric phenol with a carbonate precursor such as diphenyl carbonate. Suitable dihydric phenols include bisphenols, with 2,2-bis(4-hydroxyphenyl)propane, i.e., bisphenol A, being particularly preferred. Alternatively, bisphenol A may be partially or completely substituted with another dihydric phenol. Examples of dihydric phenols other than bisphenol A include compounds such as hydroquinone, 4,4-dihydroxydiphenyl, bis(4-hydroxyphenyl)alkane, bis(4-hydroxyphenyl)cycloalkane, bis(4-hydroxyphenyl)sulfide, bis(4-hydroxyphenyl)sulfone, bis(4-hydroxyphenyl)sulfoxide, and bis(4-hydroxyphenyl)ether, as well as halogenated bisphenols such as bis(3,5-dibromo-4-hydroxyphenyl)propane and bis(3,5-dichloro-4-hydroxyphenyl)propane. These dihydric phenols may be homopolymers or copolymers of two or more dihydric phenols. The polycarbonate resin (B) may be a thermoplastic randomly branched polycarbonate prepared by reacting a polyfunctional aromatic with a dihydric phenol and / or a carbonate precursor.

[0093] The polyester resin is a resin whose basic structure is a polycondensate of a polycarboxylic acid and a polyhydric alcohol, and known polyester resins can be used. The polycarboxylic acid is not particularly limited, but examples include aliphatic or alicyclic dicarboxylic acids such as oxalic acid, succinic acid, glutaric acid, adipic acid, sebacic acid, dimer acid, dodecanedioic acid, and 1,6-cyclohexanedicarboxylic acid; and aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid, and diphenyldicarboxylic acid. The polycarboxylic acid can be one of these or a mixture of two or more of them. On the other hand, the polyhydric alcohol is not particularly limited, and examples thereof include aliphatic or alicyclic diols such as 1,2-ethanediol, 2,2'-oxydiethanol, 2,2'-(ethylenedioxy)diethanol, 1,3-propanediol, 1,2-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, and isosorbide; xylylene glycol, 4,4'-dihydroxybiphenyl, 2,2-bis(4'-hydroxyphenyl)propane, 2,2-bis(4'-β-hydroxyethoxyphenyl)propane, bis(4-hydroxyphenyl)sulfone, and bis(4-β-hydroxyethoxyphenyl)sulfone. The polyhydric alcohol may be one of these or a mixture of two or more thereof. Examples of polyester resins include polyethylene terephthalate, polybutylene terephthalate, polybutylene succinate, polybutylene succinate adipate, polybutylene adipate terephthalate, polylactic acid, polyhydroxybutyric acid, polyethylene naphthalate, polyarylate, acid-modified polyester copolymerized with isophthalic acid, glycol-modified polyester copolymerized with 1,4-cyclohexanedimethanol (specifically, G-PET, PETG), etc. Furthermore, the polyester resins may be used alone or in combination of two or more.

[0094] The polyamide resin is not particularly limited, and various known polyamides can be used. Examples of polyamide resins include polyamide 6, polyamide 11, and polyamide 12, which are obtained by polycondensation of lactams. Also, diamines such as 1,6-hexanediamine, 2-methyl-1,5-pentanediamine, 1,7-heptanediamine, 2-methyl-1-6-hexanediamine, 1,8-octanediamine, 2-methyl-1,7-heptanediamine, 1,9-nonanediamine, 2-methyl-1,8-octanediamine, 1,10-decanediamine, 1,11-undecanediamine, 1,12-dodecanediamine, and m-xylylenediamine can be used in combination with butanedioic acid, pentanedioic acid, hexanedioic acid, heptanedioic acid, octanedioic acid, nonanedioic acid, and decanedioic acid. Examples of polyamide resins include copolymers with dicarboxylic acids such as benzene-1,2-dicarboxylic acid, benzene-1,3-dicarboxylic acid, benzene-1,4-dicarboxylic acid, cyclohexane-1,3-dicarboxylic acid, and cyclohexane-1,4-dicarboxylic acid, and specific examples include polyamide 6,6, polyamide 6,10, polyamide 6,11, polyamide 6,12, polyamide 6,T, polyamide 6,I, polyamide 9,T, polyamide 10,T, polyamide 2M5,T, polyamide MXD,6, polyamide 6,C, and polyamide 2M5,C. One type of polyamide resin may be used alone, or two or more types may be used in combination.

[0095] Examples of vinyl resins include, but are not limited to, vinyl esters such as vinyl acetate; chlorine-containing vinyl monomers such as vinyl chloride; vinyl ketones; vinyl ethers; and copolymers thereof, or copolymers thereof with other monomers. Examples include ethylene-vinyl acetate copolymer, polyvinyl chloride, polyvinyl alcohol, polyvinyl acetate, polyvinyl butyral, and polyvinyl formal. One type of vinyl resin may be used alone, or two or more types may be used in combination.

[0096] The olefin resin is not particularly limited, and various known resins can be used. Examples of the olefin resin include ethylene resins such as polyethylene, ethylene-propylene copolymer, ethylene-1-butene copolymer, ethylene-propylene-1-butene copolymer, ethylene-4-methyl-1-pentene copolymer, ethylene-1-hexene copolymer, ethylene-1-heptene copolymer, and ethylene-1-octene copolymer; propylene resins such as polypropylene, propylene-ethylene copolymer, propylene-ethylene-1-butene copolymer, propylene-ethylene-4-methyl-1-pentene copolymer, and propylene-ethylene-1-hexene copolymer; 1-butene resins such as 1-butene homopolymer, 1-butene-ethylene copolymer, and 1-butene-propylene copolymer; and 4-methyl-1-pentene resins such as 4-methyl-1-pentene homopolymer and 4-methyl-1-pentene-ethylene copolymer. The olefin resins may be used alone or in combination of two or more.

[0097] Examples of acrylic resins include polymers obtained by polymerizing monomers mainly composed of acrylate and methacrylate. Specific examples of the monomers include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, n-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, and dodecyl (meth)acrylate. Vinyl acetate can also be used as a monomer. The acrylic resin may be copolymerized with an internal crosslinking monomer in addition to these monomers. Examples of internal crosslinking monomers include acrylic acid, methacrylic acid, crotonic acid, itaconic acid, maleic acid, allyl alcohol, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 2-hydroxypropyl acrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, vinylpyridine, tert-butylaminoethyl methacrylate, glycidyl acrylate, glycidyl methacrylate, acrylic glycidyl ether, itaconic anhydride, maleic anhydride, acrylamide, methacrylamide, maleamide, N-methylol acrylamide, N-methylol methacrylamide, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, tetrahydrofurfuryl methacrylate, tetrahydrofurfuryl acrylate, 1,3-butanediol dimethacrylate, mono(2-methacryloylethyl) acid phosphate, trimethylolpropane trimethacrylate, etc. The monomers may be used alone or in combination. The acrylic resins may be used alone or in combination of two or more.

[0098] Examples of styrene resins include polystyrene, acrylonitrile-styrene resin, acrylonitrile-butadiene-styrene resin, α-methylstyrene-styrene resin, styrene-conjugated diene block resin (conjugated dienes include butadiene, isoprene, etc.), hydrogenated styrene-conjugated diene block resin (conjugated dienes include butadiene, isoprene, etc.), styrene-conjugated diene-styrene triblock resin (conjugated dienes include butadiene, isoprene, etc.), hydrogenated styrene-conjugated diene-styrene triblock resin (conjugated dienes include butadiene, isoprene, etc.), etc. One styrene resin may be used alone, or two or more may be used in combination.

[0099] It is known that the polycarbonate resin (A) is discolored due to catalyst residue contained in the polyester-based resin, and from the viewpoint of being able to expect a particular effect of suppressing discoloration, the thermoplastic resin (B) is preferably a polyester-based resin. In order to obtain a thermoplastic resin having excellent mechanical properties, the polyester resin is preferably an amorphous polyester. Furthermore, from the viewpoint of suppressing delamination of injection-molded thermoplastic resin articles, the amorphous polyester is preferably glycol-modified polyethylene terephthalate.

[0100] The thermoplastic resin (B) is preferably a rubber-modified graft polymer. In this case, the impact resistance of a molded article formed from the thermoplastic resin composition is improved. Furthermore, while conventional polycarbonate resins tend to have a decrease in optical properties and a decrease in long-term stability of optical properties as the impact resistance increases, the thermoplastic resin composition of the present disclosure inhibits the decrease in optical properties and their long-term stability, thereby enabling the production of molded articles with excellent optical properties and their long-term stability.

[0101] The rubber-modified graft polymer is preferably an elastomer having a core-shell structure. Generally, the use of a single elastomer improves impact resistance but often reduces the heat resistance of the composition. However, the use of an elastomer having a core-shell structure is preferable because it makes it easier to obtain a resin composition that has both impact resistance and heat resistance. An "elastomer with a core-shell structure" is a core-shell graft copolymer that consists of an innermost layer (core layer) and one or more layers (shell layers) covering it, and is formed by graft copolymerizing a copolymerizable monomer component with the core layer as the shell layer.

[0102] A preferred example of an elastomer having a core-shell structure is a core-shell graft copolymer, which has a core layer composed of a polymer component known as a rubber component and a shell layer formed by graft polymerization of a monomer component copolymerizable with the polymer component constituting the core layer and covering the core layer. The method for producing the core-shell graft copolymer is not particularly limited, and may be any of bulk polymerization, solution polymerization, suspension polymerization, emulsion polymerization, etc., and the copolymerization method may be single-stage or multi-stage grafting. Commercially available core-shell elastomers can also be used as they are. Examples of commercially available core-shell elastomers are listed below.

[0103] The polymer component forming the core layer typically has a glass transition temperature of 0°C or lower, preferably -10°C or lower, more preferably -20°C or lower, and even more preferably -30°C or lower. Specific examples of polymer components forming the core layer include polybutadiene, polyisoprene, polyalkyl acrylates such as polybutyl acrylate, poly(2-ethylhexyl acrylate), and butyl acrylate-2-ethylhexyl acrylate copolymers, silicone rubbers such as polyorganosiloxane rubber, butadiene-acrylic composites, IPN (Interpenetrating Polymer Network) composite rubbers consisting of polyorganosiloxane rubber and polyalkyl acrylate rubber, styrene-butadiene copolymers, ethylene-α-olefin copolymers such as ethylene-propylene copolymers, ethylene-butene copolymers, and ethylene-octene copolymers, ethylene-acrylic copolymers, and fluororubbers. These may be used alone or in combination. Among these, polybutadiene, polyalkyl acrylate, polyorganosiloxane, a composite of polyorganosiloxane and polyalkyl acrylate, and butadiene-styrene copolymer are preferred in terms of mechanical properties and surface appearance.

[0104] Specific examples of the monomer component graft-copolymerizable with the polymer component of the core layer (i.e., the monomer component of the shell layer) include aromatic vinyl compounds, vinyl cyanide compounds, (meth)acrylic acid ester compounds, (meth)acrylic acid compounds, epoxy group-containing (meth)acrylic acid ester compounds such as glycidyl (meth)acrylate; maleimide compounds such as maleimide, N-methylmaleimide, and N-phenylmaleimide; α,β-unsaturated carboxylic acid compounds such as maleic acid, phthalic acid, and itaconic acid, and anhydrides thereof (e.g., maleic anhydride, etc.). From the viewpoint of the mechanical properties and surface appearance of the molded article, aromatic vinyl compounds, vinyl cyanide compounds, (meth)acrylic acid ester compounds, and (meth)acrylic acid compounds are preferred, and (meth)acrylic acid ester compounds are more preferred. Specific examples of (meth)acrylic acid ester compounds include methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, cyclohexyl (meth)acrylate, and octyl (meth)acrylate. Among these, methyl (meth)acrylate and ethyl (meth)acrylate, which are relatively easily available, are preferred, and methyl (meth)acrylate is more preferred. Here, "(meth)acrylic" collectively refers to "acrylic" and "methacrylic." The monomer components may be used alone or in combination of two or more.

[0105] Particularly preferred elastomers having a core-shell structure are IPN composite rubbers made of polyorganosiloxane rubber and polyalkyl acrylate rubber, and core-shell graft copolymers having a core layer made of at least one polymer component selected from the group consisting of polybutadiene-containing rubber, polybutyl acrylate-containing rubber, and polyorganosiloxane rubber, and a shell layer formed by graft copolymerizing a (meth)acrylic acid ester onto the core layer. In this case, the combination of the core-shell graft copolymer with the polycarbonate resin (A) further improves the impact resistance of the thermoplastic resin composition and its molded articles. The core-shell graft copolymer preferably contains 40% by weight or more, more preferably 60% by weight or more, of the polymer component of the core layer, and the (meth)acrylic acid ester component in the shell layer is preferably 10% by weight or more.

[0106] Preferred specific examples of core-shell type graft copolymers include methyl methacrylate-butadiene-styrene copolymer (MBS), methyl methacrylate-acrylonitrile-butadiene-styrene copolymer (MABS), methyl methacrylate-butadiene copolymer (MB), methyl methacrylate-acrylic rubber copolymer (MA), methyl methacrylate-acrylic rubber-styrene copolymer (MAS), methyl methacrylate-acrylic-butadiene rubber copolymer, methyl methacrylate-acrylic-butadiene rubber-styrene copolymer, and methyl methacrylate-(acrylic-silicone complex) copolymer.

[0107] The core-shell elastomer is preferably composed of a copolymer containing a component derived from alkyl (meth)acrylate. A copolymer containing a component derived from alkyl (meth)acrylate is referred to as an "alkyl (meth)acrylate copolymer" as appropriate. Specific examples of alkyl (meth)acrylate copolymers include copolymers of alkyl (meth)acrylate and styrene, copolymers of alkyl (meth)acrylate and acrylic rubber, copolymers of alkyl (meth)acrylate, styrene and acrylic rubber, copolymers of alkyl (meth)acrylate, butadiene, styrene and acrylonitrile, copolymers of alkyl (meth)acrylate, butadiene and styrene, copolymers of alkyl (meth)acrylate and butadiene, and copolymers of alkyl (meth)acrylate and acrylic-silicone IPN rubber. "IPN" refers to an interpenetrating polymer network structure. In this case, the elastomer not only improves impact resistance but also significantly improves the optical properties of molded articles made from the resin composition of the present disclosure and inhibits deterioration of the long-term stability of the optical properties. In other words, molded articles made from the resin composition of the present disclosure will have even better optical properties and long-term stability, even though they contain an elastomer. The number of carbon atoms in the alkyl group of the alkyl methacrylate is preferably 0 to 12, more preferably 1 to 8, and even more preferably 2 to 4. The alkyl group may be linear or branched.

[0108] Such core-shell type graft copolymers are not particularly limited as long as they can obtain the effects of the present invention, and may be commercially available products. For example, "PARALOID (registered trademark) EXL2602," "PARALOID (registered trademark) EXL2603," "PARALOID (registered trademark) EXL2655," "PARALOID (registered trademark) EXL2311," "PARALOID (registered trademark) EXL2313," "PARALOID (registered trademark) EXL2315," "PARALOID (registered trademark) KM330," "PARALOID (registered trademark) KM336P," and "PARALOID (registered trademark) KCZ201," all manufactured by Rohm and Haas Japan Co., Ltd.; "METABLEN (registered trademark) C-223A" and "METABLEN (registered trademark) KCZ202," all manufactured by Mitsubishi Rayon Co., Ltd.; The adhesives that can provide the effects of the present invention can be appropriately selected from among "Kane Ace (registered trademark) E-901," "Metablen (registered trademark) S-2001," "Metablen (registered trademark) W-450A," "Metablen (registered trademark) SRK-200," and Kaneka Corporation's "Kane Ace (registered trademark) M-511," "Kane Ace (registered trademark) M-600," "Kane Ace (registered trademark) M-400," "Kane Ace (registered trademark) M-580," "Kane Ace (registered trademark) M-590," "Kane Ace (registered trademark) M-591," "Kane Ace (registered trademark) MR-01," and the like.

[0109] The core-shell structure elastomer may be used alone or in combination of two or more kinds.

[0110] [Fatty acid metal salts (C)] The thermoplastic resin composition contains a fatty acid metal salt (C) having 4 or more carbon atoms. Generally, molded articles of thermoplastic resin compositions containing polycarbonate resins tend to yellow when used in high-temperature and high-humidity environments, but the fatty acid metal salt (C) in the thermoplastic resin composition of the present invention can prevent yellowing. The long-term stability of optical properties is improved. If the fatty acid metal salt has 3 or fewer carbon atoms, yellowing may not be sufficiently prevented.

[0111] The fatty acid metal salt (C) is a salt of a fatty acid and a metal. The fatty acid in the fatty acid metal salt may be a straight-chain fatty acid or a branched-chain fatty acid. In addition, the fatty acid may be a saturated fatty acid or an unsaturated fatty acid, but saturated fatty acids are preferred from the viewpoint of long-term stability of optical properties (especially moist heat resistance). The fatty acid may be a hydroxy fatty acid having a hydroxy group other than a carboxyl group, or may be a fatty acid having no hydroxy group other than a carboxyl group, but from the viewpoint of improving moist heat resistance and suppressing yellowing, a hydroxy fatty acid is preferred. Furthermore, from the viewpoint of easy production of the fatty acid, a fatty acid having no hydroxy group other than a carboxyl group is preferred. Furthermore, a hydroxy fatty acid and a fatty acid other than a hydroxy fatty acid may be used in combination.

[0112] Examples of the fatty acid include fatty acids having, for example, 4 to 30 carbon atoms, preferably 6 to 26, more preferably 8 to 24, even more preferably 12 to 22, still more preferably 12 to 20, and even more preferably 14 to 18. When the number of carbon atoms in the fatty acid is equal to or greater than the above lower limit, the thermoplastic resin composition tends to have better moist heat resistance and to be more easily inhibited from yellowing. Furthermore, when the number of carbon atoms in the fatty acid is equal to or less than the above upper limit, the fatty acid metal salt (C) exhibits good dispersibility, making it possible to obtain a resin composition with higher uniformity and homogeneity. As described above, the thermoplastic resin composition contains the polycarbonate resin (A), the thermoplastic resin (B), and the fatty acid metal salt (C). Therefore, such a thermoplastic resin composition can provide a molded article that has good impact resistance and excellent optical properties and their long-term stability.

[0113] Specific examples of fatty acids include caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, behenic acid, lignoceric acid, montanic acid, palmitoleic acid, oleic acid, castor oil fatty acid, hydroxylauric acids such as 3-hydroxylauric acid and 12-hydroxylauric acid, hydroxymyristic acids such as 2-hydroxymyristic acid and 3-hydroxymyristic acid, hydroxypalmitic acids such as 2-hydroxypalmitic acid, 10-hydroxypalmitic acid and 16-hydroxypalmitic acid, hydroxystearic acids such as 12-hydroxystearic acid, ricinoleic acid, linoleic acid, linolenic acid, and arachidonic acid.

[0114] Preferred examples of fatty acid metal salts include zinc laurate, zinc myristate, zinc palmitate, zinc stearate, zinc 12-hydroxystearate, magnesium laurate, magnesium myristate, magnesium palmitate, magnesium stearate, magnesium 12-hydroxystearate, calcium laurate, calcium myristate, calcium palmitate, calcium stearate, calcium 12-hydroxystearate, aluminum laurate, aluminum myristate, aluminum palmitate, aluminum stearate, aluminum 12-hydroxystearate, barium laurate, barium myristate, barium palmitate, barium stearate, sodium laurate, sodium myristate, sodium palmitate, sodium stearate, sodium 12-hydroxystearate, lithium laurate, lithium myristate, lithium palmitate, lithium stearate, and lithium 12-hydroxystearate. Zinc caprylate, zinc behenate, and zinc montanate are also preferred. Of these, zinc stearate, zinc laurate, zinc 12-hydroxystearate, aluminum 12-hydroxystearate, calcium 12-hydroxystearate, aluminum stearate, calcium stearate, magnesium stearate, and lithium stearate are more preferred, and from the viewpoint of improving the dispersibility of the fatty acid metal salt (C) and the moist heat resistance of the thermoplastic resin composition in a balanced manner, thereby further improving resistance to yellowing, zinc stearate, zinc 12-hydroxystearate, aluminum stearate, aluminum 12-hydroxystearate, and lithium stearate are even more preferred, and zinc laurate stearate and zinc 12-hydroxystearate are most preferred. The fatty acid metal salt (C) may be used alone or in combination of two or more.

[0115] The content of the fatty acid metal salt (C) is 0.00001 part by mass or more and less than 0.02 part by mass per 100 parts by mass of the total of the polycarbonate resin (A) and the thermoplastic resin (B). The content of the fatty acid metal salt (C) is preferably 0.0005 parts by mass or more, more preferably 0.0010 parts by mass or more, even more preferably 0.0015 parts by mass or more, still more preferably 0.0020 parts by mass or more, and particularly preferably 0.0025 parts by mass or more. By setting the content of the fatty acid metal salt (C) to 0.00001 parts by mass or more, the fatty acid metal salt (C) can appropriately improve moist heat resistance, making yellowing less likely to occur even when used in high-temperature, high-humidity environments. Furthermore, by setting the content to less than 0.02 parts by mass, it becomes easier to achieve effects commensurate with the content. Furthermore, although there is a concern that a high content of fatty acid metal salt may result in a decrease in mechanical properties, as described above, in a thermoplastic resin composition containing a specific polycarbonate resin (A) and a thermoplastic resin (B), even a small amount of fatty acid metal salt can suppress yellowing, thereby eliminating the above-mentioned concern. The content of the fatty acid metal salt (C) is preferably 0.0200 parts by mass or less, more preferably 0.0180 parts by mass or less, even more preferably 0.0150 parts by mass or less, even more preferably 0.0120 parts by mass or less, still more preferably 0.0100 parts by mass or less, and particularly preferably 0.0080 parts by mass or less. By keeping the content of the fatty acid metal salt (C) at or below the above upper limit, it becomes easier to maintain the mechanical strength and the like of the thermoplastic resin composition at a good level, for example, it becomes easier to ensure stretchability, and it becomes easier to increase the tensile elongation and the like when formed into a molded product such as a film.

[0116] The presence or absence of fatty acid metal salts in the resin composition can be confirmed, for example, by detecting metal elements by inductively coupled plasma atomic emission spectroscopy (ICP-AES) and detecting esters having aliphatic groups by gas chromatography mass spectrometry (GC-MS). Furthermore, esters having aliphatic groups can be detected by subjecting components insoluble in good solvents for the polycarbonate resin (A), such as tetrahydrofuran and chloroform, to methanol decomposition and detecting the decomposition product by GC-MS, or by extracting the components with heated methanol and detecting the extracted components by reactive pyrolysis GC-MS.

[0117] [Light stabilizer (D)] The thermoplastic resin composition may further contain a light stabilizer (D). Examples of light stabilizers include hindered amine light stabilizers. The molecular weight of the light stabilizer is preferably 1,000 or less. In this case, the weather resistance of the molded article can be further improved. From the same viewpoint, the molecular weight of the light stabilizer is more preferably 900 or less. Furthermore, the molecular weight of the light stabilizer is preferably 300 or more. In this case, the heat resistance of the polycarbonate resin composition can be improved and mold contamination during molding can be more reliably prevented. As a result, molded articles with better surface appearance can be obtained. From the same viewpoint, the molecular weight of the light stabilizer is more preferably 400 or more.

[0118] The light stabilizer is preferably a compound having a piperidine structure. The piperidine structure defined here may be a saturated six-membered ring amine structure (specifically, a six-membered ring heterocyclic amine structure), and may also include a piperidine structure in which a portion of the piperidine structure is substituted with a substituent. Examples of the substituent include alkyl groups having four or less carbon atoms, and a methyl group is particularly preferred. The light stabilizer is more preferably a compound having a plurality of piperidine structures, and even more preferably a compound in which the plurality of piperidine structures are connected by an ester structure.

[0119] Light stabilizers include 4-piperidinol, 2,2,6,6-tetramethyl-4-benzoate, bis(2,2,6,6-tetramethyl-piperidyl)sebacate, bis(1,2,2,6,6-pentamethyl-4-piperidyl)sebacate, tetrakis(2,2,6,6-tetramethylpiperidine-4-carboxylic acid) 1,2,3,4-butanetetrayl, condensation product of 2,2,6,6-tetramethyl-pyrelidinol, tridecyl alcohol and 1,2,3,4-butanetetracarboxylic acid, 1,2,2,6,6-pentamethyl-4-piperidyl and tridecyl alcohol. Condensation products of methyl ether and tridecyl-1,2,3,4-butanetetracarboxylate, bis(1,2,3,6,6-pentamethyl-4-piperidyl)[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]methyl]butylmalonate, decanedioic acid bis(2,2,26,6-tetramethyl-1-(octyloxy)-4-piperidinyl)ester, reaction products of 1,1-dimethylethyl hydroperoxide with octane, 1-[2-[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyloxy]ethyl]-4-[ 3-(3,5-di-tert-butyl-4-4-hydroxyphenyl)propionyloxy]ethyl]-2,2,6,6-tetramethylpiperidine, tetrakis(1,2,2,6,6-pentamethyl-4-piperidyl)1,2,3,4-butanetetracarboxylate, poly[{6-(1,1,3,3-tetramethylbutyl)amino-1,3,5-triazine-2,4-diyl}{(2,2,6,6-tetramethyl-4-piperidyl)imino}hexamethylene{(2,2,6,6-tetramethyl-4-piperidyl)imino}], N,N'-bis(2,2, Polymer of 6,6-tetramethyl-4-piperidyl)-1,6-hexanediamine with 2,4,6-trichloro-1,3,5-triazine, condensation product of 1,2,3,4-butanetetracarboxylic acid, 2,2,6,6-tetramethyl-4-piperidinol and β,β,β,β,β-tetramethyl-3,9-(2,4,8,10-tetraoxaspiro[5,5]undecane-diethanol, N,N'-bis(3-aminopropyl)ethylenediamine-2,4-bis[N-butyl-N-(1,2,2,6,6-pentamethyl-4-piperidyl)amino]-6-chloro-1,3,5-triazine condensate, dimethyl succinate-1-(2-hydroxyethyl)-4-hydroxy-2,2,6,6-tetramethylpiperidine polycondensate, etc.

[0120] From the viewpoint of further improving the weather resistance of the thermoplastic resin and its molded article, the content of the light stabilizer (D) per 100 parts by mass of the thermoplastic resin is preferably 0.010 parts by mass or more, more preferably 0.030 parts by mass or more, and even more preferably 0.050 parts by mass or more. Also, from the viewpoint of further suppressing coloration, the content of the light stabilizer (D) per 100 parts by mass of the thermoplastic resin is preferably 2.0 parts by mass or less, more preferably 1.0 part by mass or less, even more preferably 0.50 parts by mass or less, even more preferably 0.30 parts by mass or less, and even more preferably 0.20 parts by mass or less.

[0121] [Other additives] The thermoplastic resin composition may further contain additives. Examples of such additives include those used in thermoplastic resins for various applications. Specific examples include release agents, catalyst deactivators, ultraviolet absorbers, laser coloring agents, antioxidants, heat stabilizers, process stabilizers, matting agents, processing aids, metal deactivators, residual polymerization catalyst deactivators, antibacterial and antifungal agents, antiviral agents, antistatic agents, internal lubricants, flame retardants, colorants (pigments, dyes, etc.), inorganic fillers, etc. These additives may be added in amounts typically used depending on the intended use. These additives may be used alone or in combination of two or more.

[0122] [Application] The thermoplastic resin composition of the present disclosure has improved optical properties such as transparency and color tone, and also has excellent impact resistance, heat resistance, and moist heat resistance, making it suitable for a wide range of applications as a molding material for various products. These thermoplastic resin compositions and molded articles are expected to be used in a wide range of fields, including injection-molded products such as electrical and electronic components and automotive parts, films, sheets, and even building materials. [Example]

[0123] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to the following examples as long as the gist of the invention is not exceeded.

[0124] [Evaluation method] In the following, the physical properties and characteristics of the polycarbonate resin and resin composition were evaluated by the following methods.

[0125] (1) Transparency (total light transmittance / haze) Pellets of the thermoplastic resin composition were dried at 90°C for at least 6 hours using a hot air dryer. The dried pellets were then fed into an injection molding machine (J85AD, manufactured by The Japan Steel Works, Ltd.) and molded under conditions of a resin temperature of 240°C, a mold temperature of 60°C, and a molding cycle of 50 seconds to obtain injection-molded plates (100mm wide x 100mm long x 2mm thick). The total light transmittance and haze of the injection-molded plates were measured using a haze meter "NDH7000II" manufactured by Nippon Denshoku Industries Co., Ltd. under a D65 light source in accordance with JIS K7136 (2000). A higher total light transmittance value indicated better transparency, with a value of 88% or higher being considered to be excellent transparency. A lower haze value indicated better transparency, with a value of 5% or lower being considered to be excellent transparency.

[0126] (2) Yellowing index (YI value) The plates were subjected to moist heat treatment for 7 days at 65°C and 95% RH using a HIFLEX FX410N manufactured by Kusumoto Chemicals Co., Ltd. The yellowing index (YI) was measured for the plates before and after the moist heat treatment using a spectrophotometer "CM-5" manufactured by Konica Minolta Inc. under Illuminant C. The evaluation based on yellowing index was made according to the following criteria. In this example, a YI value of 3 or less was considered to have excellent hue. YI stands for yellow index.

[0127] (3) MFR measurement method The thermoplastic resin composition pellets were dried using a hot air dryer at 90°C for 6 hours or more, and then the MFR of the pellets was measured using a melt indexer (manufactured by Toyo Seiki Seisakusho, Ltd.) according to JIS K7210 under conditions of a temperature of 230°C and a load of 2.16 kg.

[0128] (4) Glass transition temperature Measurements were performed using a differential scanning calorimeter (DSC6220, SII NanoTechnology). Approximately 10 mg of polycarbonate resin sample was placed in a sealed aluminum pan manufactured by SII NanoTechnology and heated from room temperature to 250°C at a rate of 20°C / min under a 50 mL / min nitrogen flow. After holding the temperature for 3 minutes, the sample was cooled to 30°C at a rate of 20°C / min. The sample was then held at 30°C for 3 minutes and again heated to 200°C at a rate of 20°C / min. From the DSC data obtained during the second heating run, the extrapolated glass transition onset temperature (Tg) was calculated as the temperature at the intersection of a line drawn by extending the low-temperature baseline toward the high-temperature side and a tangent drawn at the point where the gradient of the step-like portion of the glass transition curve is maximized. This was used as the Tg.

[0129] (5) Reduced viscosity A polycarbonate resin sample was dissolved in methylene chloride as a solvent to prepare a polycarbonate solution with a concentration of 0.6 g / dL. Measurements were carried out at a temperature of 20.0°C ± 0.1°C using an Ubbelohde viscometer manufactured by Moritomo Rika Kogyo Co., Ltd., and the relative viscosity η was calculated from the solvent transit time t0 and the solution transit time t using the following equation: rel Seeking η rel =t / t0 From the relative viscosity, the specific viscosity η is calculated using the following formula: sp asked for. η sp =(η-η0) / η0=η rel -1 Divide the specific viscosity by the concentration c (g / dL) to get the reduced viscosity η sp / c The higher this value, the larger the molecular weight.

[0130] (6) Humidity and heat test Pellets of the thermoplastic resin composition were dried at 90°C for 6 hours or more using a hot air dryer (box dryer PO-80, manufactured by Matsui Manufacturing Co., Ltd.). Next, the dried pellets were fed into an injection molding machine (J85AD, manufactured by The Japan Steel Works, Ltd.) and molded under conditions of a resin temperature of 240°C, a mold temperature of 60°C, and a molding cycle of 50 seconds to obtain an injection-molded plate (100 mm wide x 100 mm long x 2 mm thick). This molded plate was left to stand for a predetermined time (specifically, 400 hours, 600 hours, or 1000 hours) under conditions of a temperature of 85°C and a relative humidity of 85% in an ETAC HIFLEX FX224P manufactured by Kusumoto Chemical Co., Ltd. This allowed for a predetermined time of moist heat test. The total light transmittance and haze of the injection-molded plate were measured using a haze meter "NDH7000II" manufactured by Nippon Denshoku Industries Co., Ltd., in accordance with JIS K7136 (2000), using a D65 light source. The change in YI (ΔYI) before and after the moist heat test was measured using a Konica Minolta CM-5 spectrophotometer under Illuminant C in accordance with JIS K7136 (2000). The difference in YI (ΔYI) before and after the moist heat test was calculated. The total luminous transmittance (TT) and haze after the moist heat test were also measured, and the difference in total luminous transmittance (ΔTT) and haze before and after the test were calculated. In this evaluation, the smaller the ΔYI value, the smaller the change in color tone when used for a long period of time in a high-temperature, high-humidity environment, indicating superior resistance to moist heat. Similarly, the smaller the change in total light transmittance or haze before and after the moist heat test, the smaller the change in transparency when used for a long period of time in a high-temperature, high-humidity environment, indicating excellent long-term stability of optical properties. In this example, when the change in total light transmittance before and after the moist heat test in this evaluation was 2.0 or less and the change in haze was 4.0 or less, it was determined that the long-term stability of optical properties was excellent. Furthermore, when the change in total light transmittance before and after the moist heat test was 1.5 or less and the change in haze was 2.0 or less, it was determined that the long-term stability of optical properties was particularly excellent. In particular, those in which the change in total light transmittance before and after the moist heat resistance test was 1.0 or less and the ΔYI value before and after the moist heat resistance test was 1.0 or less were considered to have extremely excellent moist heat resistance.

[0131] (7) Dry heat test In the same manner as in the wet heat test, an injection-molded plate (100 mm wide x 100 mm long x 2 mm thick) was obtained. This molded plate was then left to stand for a predetermined time (specifically, 400 hours, 600 hours, or 1000 hours) at a temperature of 100°C in a HIFLEX FX410N manufactured by Kusumoto Chemicals Co., Ltd. This resulted in a dry heat test for the predetermined time. Then, YI and ΔYI were measured.

[0132] [Raw materials used] The abbreviations and manufacturers of the compounds used in the following Examples and Comparative Examples are as follows: [Polycarbonate resin (A)] <Dihydroxy compounds> ISB: Isosorbide [Rocket Fleuret] CHDM: 1,4-cyclohexanedimethanol [SK Chemical] <Carbonate diester> DPC: Diphenyl carbonate [Mitsubishi Chemical Corporation] <Catalyst deactivator (acidic compound)> Phosphorous acid [Taihei Chemical Industry Co., Ltd.] (molecular weight 82.0) <Heat stabilizer (antioxidant)> Irganox 1010: Pentaerythritol tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate][BASF] ADK STAB 2112: Tris(2,4-di-tert-butylphenyl) phosphite [ADEKA Corporation] (molecular weight 646.9) <Release agent> Unistar E-275: Ethylene glycol distearate [NOF Corporation]

[0133] [Thermoplastic resin (B)] Thermoplastic resin B-1: Polyester (PETG): Easter (registered trademark) GN001 [manufactured by Eastman Chemical Japan Co., Ltd.] Thermoplastic resin B-2: Core-shell type rubber: Kane Ace (registered trademark) M-591 [manufactured by Kaneka Corporation] Thermoplastic resin B-3: Core-shell type rubber: Kane Ace (registered trademark) M-592 [manufactured by Kaneka Corporation]

[0134] [Fatty acid metal salts (C)] Fatty acid metal salt C-1: Zinc 12-hydroxystearate: "ZS-6" manufactured by Nitto Kasei Kogyo Co., Ltd. Fatty acid metal salt C-2: Aluminum C12-hydroxystearate: Fujifilm Wako Pure Chemical Industries, Ltd. Fatty acid metal salt C-3: 12-hydroxystearate calcium: "CS-6" manufactured by Nitto Kasei Kogyo Co., Ltd. Fatty acid metal salt C-4: Aluminum stearate: "Al-St" manufactured by Nitto Kasei Kogyo Co., Ltd. Fatty acid metal salt C-5: Calcium stearate: Fujifilm Wako Pure Chemical Industries, Ltd. Fatty acid metal salt C-6: Magnesium stearate: Fujifilm Wako Pure Chemical Industries, Ltd. Fatty acid metal salt C-7: Sodium stearate: Fujifilm Wako Pure Chemical Industries, Ltd. Fatty acid metal salt C-8: Lithium stearate: Manufactured by Fujifilm Wako Pure Chemical Industries, Ltd. Fatty acid metal salt C-9: Sodium laurate: Fujifilm Wako Pure Chemical Industries, Ltd. Fatty acid metal salt C-10: Sodium caprylate: Fujifilm Wako Pure Chemical Industries, Ltd. Fatty acid metal salt C-11: Sodium acetate: Fujifilm Wako Pure Chemical Industries, Ltd.

[0135] Light stabilizer D-1: HALS: ADEKA "ADEKA STAB LA-57" Light stabilizer D-2: HALS: ADEKA "ADEKA STAB LA-52" Other additives E-2 (UV absorber): Benzotriazole: Seesorb 709 manufactured by Shipro Chemical Co., Ltd. Other additives E-1: Pigment: TiO2: HUNTSMAN "RTC-30"

[0136] [Production Example 1 of Polycarbonate Resin (A)] Polycarbonate resin polymerization was carried out using a continuous polymerization system consisting of three vertical stirred reactors, one horizontal stirred reactor, and a twin-screw extruder. Specifically, ISB, CHDM, and DPC were melted in tanks and continuously fed into the first vertical stirred reactor at flow rates of 35.2 kg / hr for ISB, 14.9 kg / hr for CHDM, and 74.5 kg / hr for DPC (molar ratio ISB / CHDM / DPC = 0.700 / 0.300 / 1.010). Simultaneously, an aqueous solution of calcium acetate monohydrate was fed into the first vertical stirred reactor at a catalyst concentration of 1.5 μmol of calcium acetate monohydrate per mol of total dihydroxy compounds. The reaction temperature, internal pressure, and residence time of each reactor were as follows: first vertical stirred reactor: 190°C, 25 kPa, 90 minutes; second vertical stirred reactor: 195°C, 10 kPa, 45 minutes; third vertical stirred reactor: 210°C, 3 kPa, 45 minutes; and fourth horizontal stirred reactor: 225°C, 0.5 kPa, 90 minutes. The internal pressure of the fourth horizontal stirred reactor was finely adjusted during operation so that the reduced viscosity of the resulting polycarbonate resin would be 0.41 dL / g to 0.43 dL / g.

[0137] Polycarbonate resin was extracted from the fourth horizontal stirred reactor at a rate of 60 kg / hr. The resin was then fed in its molten state into a vented twin-screw extruder [TEX30α, manufactured by The Japan Steel Works, Ltd., L / D: 42.0, L (mm): screw length, D (mm): screw diameter]. The polycarbonate resin passing through the extruder was then passed through a candle-type filter (made of SUS316) with 10 μm openings while still in its molten state to filter out impurities. The polycarbonate resin was then discharged in the form of strands from the die, water-cooled, solidified, and pelletized using a rotary cutter to obtain a copolymer polycarbonate resin with an ISB / CHDM molar ratio of 70 / 30 mol%.

[0138] The extruder had three vacuum vents, through which residual low-molecular-weight components in the resin were removed by volatilization. Just before the second vent, 2000 ppm by weight of water was added to the resin, and water injection volatilization was performed. Just before the third vent, 0.1 parts by weight, 0.05 parts by weight, and 0.3 parts by weight of Irganox 1010, AS2112, and E-275 were added, respectively, per 100 parts by weight of polycarbonate resin. As a result, ISB / CHDM copolymer polycarbonate resin pellets were obtained. 0.65 ppm by weight of phosphorous acid (0.24 ppm by weight in terms of phosphorus atoms) was added to the polycarbonate resin as a catalyst deactivator. The phosphorous acid was added as follows: A masterbatch was prepared by mixing the polycarbonate resin pellets obtained in Production Example 1 with an ethanol solution of phosphorous acid, and the masterbatch was fed into the extruder just before the first vent port (on the resin feed port side of the extruder) so that the masterbatch was 1 part by mass per 100 parts by mass of the polycarbonate resin in the extruder.

[0139] The polycarbonate resin (A) obtained in Production Example 1 is referred to as polycarbonate resin A-1. The physical properties of polycarbonate resin A-1 are as follows. Glass transition temperature: 125℃ Reduced viscosity: 0.42 dL / g Melt viscosity (240℃, shear rate 91.2sec -1 ):720 Pa·s

[0140] [Production Example 2 of Polycarbonate Resin (A)] Carbonate copolymer pellets were prepared in the same manner as in Production Example 1, except that the molar ratio of the raw materials continuously supplied to the first vertical stirred reactor was changed to ISB / CHDM / DPC = 0.50 / 0.50 / 1.00.

[0141] The polycarbonate resin (A) obtained in Production Example 2 is referred to as polycarbonate resin A-2. The physical properties of polycarbonate resin A-2 are as follows. Glass transition temperature: 100℃ Reduced viscosity: 0.50 dL / g

[0142] [Example 1] The copolymer polycarbonate resin obtained in Production Example 1, the thermoplastic resin (B-1), and the fatty acid metal salt (C-1) were mixed in the proportions shown in Table 1 and extrusion-kneaded using a Technovel KZW-15 extrusion kneader at a cylinder temperature of 240°C and an extrusion rate of 2 kg / hr to obtain pellets of a thermoplastic resin composition. The resulting kneaded resin was dried in a hot air dryer at 90°C for at least 6 hours, and the dried pellets were fed into an injection molding machine (The Japan Steel Works, Ltd. J85AD) and molded under conditions of a resin temperature of 240°C, a mold temperature of 60°C, and a molding cycle of 50 seconds to obtain an injection-molded plate (100 mm wide x 100 mm long x 2 mm thick). The resulting injection plate was subjected to the various evaluations described above. The results are shown in Table 1.

[0143] [Example 2, Comparative Examples 1 and 2] Pellets and plates of the thermoplastic resin composition were prepared in the same manner as in Example 1, except that the formulation was changed as shown in Table 1, and various evaluations were carried out.

[0144] [Table 1]

[0145] As shown in Table 1, comparing Example 1 with Comparative Example 1, and Example 2 with Comparative Example 2, the resin compositions of Examples 1 and 2 exhibited reduced initial YI, YI after the wet heat test, and ΔYI, demonstrating excellent color tone and long-term color tone stability. This is because the resin compositions of the Examples contain a fatty acid metal salt (C). Note that in Table 1, the color tone ΔYI value differs from the difference between the initial value and the value after 720 hours. This is because the decimal point was rounded off in the calculation. The same applies to the differences in the following tables.

[0146] [Examples 3 and 4, Comparative Examples 3 and 4] Pellets and plates of the thermoplastic resin composition were prepared and various evaluations were carried out in the same manner as in Example 1, except that the composition was changed as shown in Table 2. The results are shown in Table 2.

[0147] [Table 2]

[0148] As shown in Table 2, comparing Example 3 with Comparative Example 3 and Example 4 with Comparative Example 4, the resin compositions of Example 3 and Example 4 maintained good transparency while exhibiting reduced initial YI, YI after the moist heat test, and ΔYI. Furthermore, the total light transmittance (TT) after the moist heat test was maintained at a high level, and the change in ΔTT was also reduced. In other words, the thermoplastic resin compositions of the Examples were found to be excellent in color tone and long-term stability of color tone, as well as long-term stability of transparency. This is likely due to the inclusion of a fatty acid metal salt (C) in the thermoplastic resin compositions of the Examples.

[0149] [Examples 5 to 16, Comparative Example 5] Pellets and plates of the thermoplastic resin composition were prepared in the same manner as in Example 1, except that the formulation of the resin composition was as shown in Table 3, and the various evaluations described above were carried out. The results are shown in Table 4.

[0150] [Table 3]

[0151] [Table 4]

[0152] The following can be seen from Tables 3 and 4. Regarding transparency, as can be seen from comparing the total light transmittance and haze values ​​before and after the wet heat test and the dry heat test, Examples 5 to 16 exhibited transparency and long-term stability of transparency equivalent to or better than that of Comparative Example 5. Furthermore, with regard to color tone, Comparative Example 5 had an initial YI value of over 2.0 in the moist heat test and dry heat test, a ΔYI of 2.5 or more after the 600-hour moist heat test, and a ΔYI of 3.4 or more after the 1000-hour dry heat test, while Examples 5 to 16 all had initial YI values ​​of less than 2.0, a ΔYI of 2.4 or less after the 600-hour moist heat test, and a ΔYI of 3.0 or less after the 1000-hour dry heat test. In other words, Examples 5 to 16 were superior to Comparative Example 5 in terms of initial color tone and long-term color tone stability.

[0153] These results demonstrate that the present invention can provide resin compositions and molded articles that are excellent in optical properties such as transparency and color tone, and in long-term stability of the optical properties, even when the type of polycarbonate resin (A) or the type and amount of fatty acid metal salt (C) is changed in various ways. Furthermore, since Examples 5 to 16 had lower initial YI values ​​and ΔYI than Examples 1 to 4, it can be seen that in the present invention, by using a polyester-based resin (specifically, an amorphous polyester-based resin such as glycol-modified polyethylene terephthalate) as the thermoplastic resin (B), the color tone tends to be particularly excellent, yellowing tends to be suppressed, and the optical properties tend to be further improved.

[0154] [Examples 17 to 23, Comparative Examples 6 to 8] Pellets and plates of the thermoplastic resin composition were prepared and various evaluations were carried out in the same manner as in Example 1, except that the composition was changed as shown in Table 5. The results are shown in Tables 6 and 7.

[0155] [Table 5]

[0156] [Table 6]

[0157] [Table 7]

[0158] The following can be seen from Tables 5 to 7. First, in the case of Comparative Example 6 where no fatty acid metal salt was contained, the YI increased significantly after the wet heat test, indicating that there are problems with the long-term stability of color tone and therefore with the optical properties. In contrast, as in Examples 17 to 23, when the thermoplastic resin composition contains the polycarbonate resin (A), the thermoplastic resin (B), and the fatty acid metal salt (C), and the fatty acid metal salt (C) contains a fatty acid metal salt having 4 or more carbon atoms, the initial color tone YI is good and the YI value after the moist heat test actually decreases, indicating that a polycarbonate resin composition having particularly excellent long-term color tone stability can be provided. Furthermore, it can be seen that the above-described embodiments (specifically, Examples 17 to 23) provide polycarbonate resin compositions that have low rates of change in total light transmittance and haze value, and are particularly excellent in transparency and long-term stability of transparency. By using these polycarbonate resin compositions, molded articles that are excellent in color tone, transparency, and long-term stability thereof, and have good optical properties, can be provided.

[0159] [Example 24, Comparative Examples 9 to 11] Pellets and plates of the thermoplastic resin composition were prepared in the same manner as in Example 1, except that the formulation of the resin composition was as shown in Table 8, and the various evaluations described above were carried out. The results are shown in Tables 9 and 10.

[0160] [Table 8]

[0161] [Table 9]

[0162] [Table 10]

[0163] As shown in Tables 8 to 10, Example 24 is superior to Comparative Examples 9 to 11 in the initial YI value, YI after the wet heat test, and haze value. Thus, it is clear that by setting the content of fatty acid metal salt (C) to approximately less than 200 ppm per 100 parts by mass of the total amount of polycarbonate resin (A) and thermoplastic resin (B), it is possible to provide a polycarbonate resin composition and a molded article having excellent optical properties and their long-term stability.

[0164] As described above, the present invention can provide a thermoplastic resin composition that can give high-quality molded articles.

Claims

1. A polycarbonate resin (A) containing a structural unit represented by the following formula (1), a thermoplastic resin (B) other than the polycarbonate resin (A); (C) a metal salt of a saturated or unsaturated fatty acid having 4 or more carbon atoms, a content of the fatty acid metal salt (C) relative to a total of 100 parts by mass of the polycarbonate resin (A) and the thermoplastic resin (B) being 0.00001 parts by mass or more and less than 0.02 parts by mass; 【Chemistry 1】

2. 2. The thermoplastic resin composition according to claim 1, wherein the content of the polycarbonate resin (A) is 50 parts by mass or more and 99.9 parts by mass or less relative to 100 parts by mass of the total of the polycarbonate resin (A) and the thermoplastic resin (B).

3. 2. The thermoplastic resin composition according to claim 1, wherein the metal of the fatty acid metal salt (C) is at least one selected from the group consisting of zinc, aluminum, calcium, magnesium, barium, sodium, and lithium.

4. 2. The thermoplastic resin composition according to claim 1, wherein the thermoplastic resin (B) comprises at least one selected from the group consisting of polycarbonate resins, polyester-based resins, polyamide-based resins, vinyl-based resins, olefin-based resins, acrylic-based resins, and styrene-based resins.

5. The thermoplastic resin composition according to claim 1, further comprising 0.010 to 2.0 parts by mass of a light stabilizer (D) relative to 100 parts by mass of the thermoplastic resin composition.

6. The thermoplastic resin composition according to any one of claims 1 to 5, wherein the thermoplastic resin (B) is a rubber-modified graft polymer.

7. 7. The thermoplastic resin composition according to claim 6, wherein the rubber-modified graft polymer is an elastomer having a core-shell structure.

8. The thermoplastic resin composition according to claim 7, wherein the elastomer is a copolymer containing a component derived from an alkyl (meth)acrylate.

9. The thermoplastic resin composition according to any one of claims 1 to 5, wherein the thermoplastic resin (B) is a polyester-based resin.

10. The thermoplastic resin composition according to claim 9 , wherein the polyester-based resin is an amorphous polyester.

11. The thermoplastic resin composition according to claim 10, wherein the amorphous polyester is glycol-modified polyethylene terephthalate.

12. A molded article formed from the thermoplastic resin composition according to any one of claims 1 to 5.

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