Polycarbonate resin composition

Abstract

To provide a polycarbonate resin composition which has high weather resistance and excellent impact resistance, heat resistance and flowability (moldability).SOLUTION: A polycarbonate resin composition contains, with respect to 100 pts.mass of the total of (A) and (B) of 55 to 90 mass% of a polycarbonate resin (A) having a viscosity average molecular weight of 17,500 to 30,000, and 10 to 45 mass% of a graft copolymer (B) containing an aromatic vinyl monomer component (b1), a vinyl cyanide monomer component (b2) and a diene-based rubbery polymer component (b3), 0.001 to 0.3 pts.mass of triaryl phosphate (C) represented by specific general formula (1), and 0.001 to 0.3 pts.mass of a compound (D) having a phenol structure, wherein the compound (D) having the phenol structure contains at least one of 4-t-butylphenol, 2,4-di-t-butylphenol, 4-α-cumylphenol, and bisphenol A.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a polycarbonate resin composition, and more particularly to a polycarbonate resin composition with excellent weather resistance and a molded article thereof. [Background technology]

[0002] Polycarbonate resin has excellent mechanical properties such as impact resistance, as well as excellent heat resistance and transparency, and is therefore widely used in many applications such as various optical components, electrical and electronic equipment components, automotive interior and exterior parts, office automation equipment parts, sheets, machine parts, and building materials. However, polycarbonate resin does not have sufficient weather resistance, and its use has been somewhat restricted, for example, when used outdoors or indoors under fluorescent lighting, as it can cause discoloration or a decrease in strength.

[0003] For this reason, various light stabilizers have been used individually or in combination, and it is known that UV absorbers such as benzotriazoles are incorporated. However, when such UV absorbers are incorporated into polycarbonate resin, there is a problem that thermal degradation during melt mixing and molding processes worsens the hue of the polycarbonate resin composition. Furthermore, various additives are used to enhance the functionality of the polycarbonate resin. For example, Patent Document 1 describes that by mixing 5 to 15% by mass of triphenyl phosphate with 85 to 95% by mass of polycarbonate resin, a fiber-reinforced polycarbonate resin composition with excellent dimensional stability, mechanical strength, and fluidity can be obtained.

[0004] In recent years, as various types of equipment have become increasingly sophisticated and high-performance, there has been a strong demand for improved weather resistance, particularly for polycarbonate resins. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Patent No. 3308657 [Overview of the project] [Problems that the invention aims to solve]

[0006] The object (problem) of the present invention is to provide a polycarbonate resin composition that has excellent weather resistance, good impact resistance, heat resistance, and fluidity (moldability). [Means for solving the problem]

[0007] As a result of diligent research to achieve the above objectives, the inventors of the present invention have discovered that a polycarbonate resin composition containing a small amount of a specific triaryl phosphate compound in a resin alloy with a graft polymer such as ABS resin exhibits excellent weather resistance while maintaining good impact resistance and heat resistance, thus completing the present invention. The present invention relates to the following polycarbonate resin compositions and molded articles.

[0008] 1. A total of 100 parts by mass of (A) and (B) containing 55 to 90% by mass of polycarbonate resin (A) with a viscosity-average molecular weight of 17,500 to 30,000, and 10 to 45% by mass of graft copolymer (B) containing aromatic vinyl monomer component (b1), vinyl cyanide monomer component (b2), and diene-based rubber polymer component (b3), It contains 0.001 to 0.3 parts by mass of a triaryl phosphate (C) represented by the following general formula (1), and 0.001 to 0.3 parts by mass of a compound (D) having a phenol structure. A polycarbonate resin composition characterized in that compound (D) having a phenolic structure contains at least one of 4-t-butylphenol, 2,4-di-t-butylphenol, 4-α-cumylphenol, and bisphenol A. [ka] [In formula (1), R 1 ~R 5 These are, independently, a hydrogen atom and an alkyl group having 1 to 12 carbon atoms. 2. In formula (1), R on each aromatic ring 1 ~R 5 The polycarbonate resin composition according to 1 above, wherein at least one of them is an alkyl group having 1 to 12 carbon atoms. 3. In formula (1), R on each aromatic ring 1 , R 3 is an alkyl group having 1 to 12 carbon atoms, and R on each aromatic ring 2 , R 4 and R 5 are hydrogen atoms. The polycarbonate resin composition according to 1 above. 4. In formula (1), R on each aromatic ring 1 , R 3 are t-butyl groups, and R on each aromatic ring 2 , R 4 and R 5 are hydrogen atoms. The polycarbonate resin composition according to 3 above. 5. The polycarbonate resin composition according to 1 above, wherein the triaryl phosphate (C) contains at least one of triphenyl phosphate, tris 2,4-di-t-butyl phosphate, and tris-4-t-butyl phosphate. 6. Further, the polycarbonate resin composition according to 1 above, which contains 0.001 to 0.3 parts by mass of triaryl phosphite (E) with respect to 100 parts by mass in total of (A) and (B). 7. Pellets of the polycarbonate resin composition according to any one of 1 to 6 above. 8. A molded article made of the polycarbonate resin composition according to any one of 1 to 6 above. 9. A molded article made of the pellets of the polycarbonate resin composition according to 7 above.

Advantages of the Invention

[0009] The polycarbonate resin composition of the present invention has high weather resistance and is excellent in impact resistance, heat resistance, and fluidity (moldability).

Modes for Carrying Out the Invention

[0010] The present invention will be described in detail below with reference to embodiments and examples. In this specification, unless otherwise specified, "~" means that the numbers before and after it are included as the lower and upper limits.

[0011] The polycarbonate resin composition of the present invention contains 55 to 90% by mass of a polycarbonate resin (A) having a viscosity-average molecular weight of 17,500 to 30,000, and 10 to 45% by mass of a graft copolymer (B) containing an aromatic vinyl monomer component (b1), a vinyl cyanide monomer component (b2), and a diene-based rubbery polymer component (b3). For every 100 parts by mass of (A) and (B) in total, the composition contains 0.001 to 0.3 parts by mass of a triaryl phosphate (C) represented by the general formula (1) and 0.001 to 0.3 parts by mass of a compound (E) having a phenolic structure. The compound (D) having a phenolic structure is characterized by containing at least one of 4-t-butylphenol, 2,4-di-t-butylphenol, 4-α-cumylphenol, and bisphenol A.

[0012] [Polycarbonate resin (A)] The polycarbonate resin (A) used in the present invention is not particularly limited, and various types can be used. Polycarbonate resins can be classified into aromatic polycarbonate resins, in which the carbon atoms directly bonded to the carbonate bonds are aromatic carbon atoms, and aliphatic polycarbonate resins, in which the carbon atoms are aliphatic carbon atoms, and either can be used. Among these, aromatic polycarbonate resin is preferred as the polycarbonate resin (A) from the viewpoint of heat resistance, mechanical properties, electrical properties, etc.

[0013] Examples of aromatic dihydroxy compounds among the monomers used as raw materials for aromatic polycarbonate resins include: Dihydroxybenzenes such as 1,2-dihydroxybenzene, 1,3-dihydroxybenzene (i.e., resorcinol), and 1,4-dihydroxybenzene; Dihydroxybiphenyls such as 2,5-dihydroxybiphenyl, 2,2'-dihydroxybiphenyl, and 4,4'-dihydroxybiphenyl;

[0014] Dihydroxynaphthalene compounds such as 2,2'-dihydroxy-1,1'-binaphthyl, 1,2-dihydroxynaphthalene, 1,3-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, 1,7-dihydroxynaphthalene, and 2,7-dihydroxynaphthalene;

[0015] Dihydroxydiaryl ethers such as 2,2'-dihydroxydiphenyl ether, 3,3'-dihydroxydiphenyl ether, 4,4'-dihydroxydiphenyl ether, 4,4'-dihydroxy-3,3'-dimethyldiphenyl ether, 1,4-bis(3-hydroxyphenoxy)benzene, and 1,3-bis(4-hydroxyphenoxy)benzene;

[0016] 2,2-bis(4-hydroxyphenyl)propane (i.e., bisphenol A), 1,1-Bis(4-hydroxyphenyl)propane, 2,2-Bis(3-methyl-4-hydroxyphenyl)propane (i.e., bisphenol C), 2,2-bis(3-methoxy-4-hydroxyphenyl)propane, 2-(4-hydroxyphenyl)-2-(3-methoxy-4-hydroxyphenyl)propane, 1,1-Bis(3-t-butyl-4-hydroxyphenyl)propane, 2,2-bis(3,5-dimethyl-4-hydroxyphenyl)propane, 2,2-Bis(3-cyclohexyl-4-hydroxyphenyl)propane, 2-(4-hydroxyphenyl)-2-(3-cyclohexyl-4-hydroxyphenyl)propane, α,α'-bis(4-hydroxyphenyl)-1,4-diisopropylbenzene, 1,3-bis[2-(4-hydroxyphenyl)-2-propyl]benzene, Bis(4-hydroxyphenyl)methane, Bis(4-hydroxyphenyl)cyclohexylmethane, Bis(4-hydroxyphenyl)phenylmethane, Bis(4-hydroxyphenyl)(4-propenylphenyl)methane, Bis(4-hydroxyphenyl)diphenylmethane, Bis(4-hydroxyphenyl)naphthylmethane, 1,1-bis(4-hydroxyphenyl)ethane, 1,1-bis(4-hydroxyphenyl)-1-phenylethane, 1,1-bis(4-hydroxyphenyl)-1-naphthylethane, 1,1-Bis(4-hydroxyphenyl)butane, 2,2-bis(4-hydroxyphenyl)butane, 2,2-bis(4-hydroxyphenyl)pentane, 1,1-Bis(4-hydroxyphenyl)hexane, 2,2-bis(4-hydroxyphenyl)hexane, 1,1-bis(4-hydroxyphenyl)octane, 2,2-bis(4-hydroxyphenyl)octane, 4,4-bis(4-hydroxyphenyl)heptane, 2,2-bis(4-hydroxyphenyl)nonane, 1,1-bis(4-hydroxyphenyl)decane, 1,1-Bis(4-hydroxyphenyl)dodecane, Bis(hydroxyaryl)alkanes such as;

[0017] 1,1-Bis(4-hydroxyphenyl)cyclopentane, 1,1-Bis(4-hydroxyphenyl)cyclohexane, 1,1-bis(4-hydroxyphenyl)-3,3-dimethylcyclohexane, 1,1-bis(4-hydroxyphenyl)-3,4-dimethylcyclohexane, 1,1-bis(4-hydroxyphenyl)-3,5-dimethylcyclohexane, 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane, 1,1-Bis(4-hydroxy-3,5-dimethylphenyl)-3,3,5-trimethylcyclohexane, 1,1-bis(4-hydroxyphenyl)-3-propyl-5-methylcyclohexane, 1,1-bis(4-hydroxyphenyl)-3-t-butyl-cyclohexane, 1,1-Bis(4-hydroxyphenyl)-4-t-butylcyclohexane, 1,1-bis(4-hydroxyphenyl)-3-phenylcyclohexane, 1,1-Bis(4-hydroxyphenyl)-4-phenylcyclohexane, Bis(hydroxyaryl)cycloalkanes such as;

[0018] 9,9-Bis(4-hydroxyphenyl)fluorene, Bisphenols containing cardo structures, such as 9,9-bis(4-hydroxy-3-methylphenyl)fluorene;

[0019] 4,4'-Dihydroxydiphenyl sulfide, Dihydroxydiaryl sulfides such as 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfide; Dihydroxydiaryl sulfoxides such as 4,4'-dihydroxydiphenyl sulfoxide and 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfoxide; 4,4'-Dihydroxydiphenylsulfone, Dihydroxydiarylsulfones such as 4,4'-dihydroxy-3,3'-dimethyldiphenylsulfone; These are some examples.

[0020] Among these, bis(hydroxyaryl)alkanes are preferred, and among them, bis(4-hydroxyphenyl)alkanes are preferred, and in particular, 2,2-bis(4-hydroxyphenyl)propane (i.e., bisphenol A) and 2,2-bis(3-methyl-4-hydroxyphenyl)propane (i.e., bisphenol C) are preferred from the viewpoint of impact resistance and heat resistance. Furthermore, one aromatic dihydroxy compound may be used, or two or more may be used in any combination and ratio.

[0021] Among the monomers used as raw materials for polycarbonate resin, examples of carbonate precursors include carbonyl halides and carbonate esters. Note that one type of carbonate precursor may be used, or two or more types may be used in any combination and ratio.

[0022] Examples of carbonyl halides include, specifically, phosgene; bischloroformates of dihydroxy compounds; monochloroformates of dihydroxy compounds; and other haloformates.

[0023] Examples of carbonate esters include diaryl carbonates such as diphenyl carbonate and dityl carbonate; dialkyl carbonates such as dimethyl carbonate and diethyl carbonate; and carbonates of dihydroxy compounds such as biscarbonates, monocarbonates, and cyclic carbonates of dihydroxy compounds.

[0024] The method for producing the polycarbonate resin (A) is not particularly limited, and any method can be used. Examples include interfacial polymerization, molten transesterification, pyridine method, ring-opening polymerization of cyclic carbonate compounds, and solid-phase transesterification of prepolymers. Among these, interfacial polymerization and molten transesterification are preferred because they offer a greater improvement in moisture and heat resistance, with interfacial polymerization being particularly preferred.

[0025] The molecular weight of the polycarbonate resin (A) is the viscosity-average molecular weight (Mv) calculated from the solution viscosity measured at 25°C using methylene chloride as the solvent, preferably 10,000 to 50,000, more preferably 10,000 to 40,000, more preferably 10,000 to 30,000, and more preferably 10,000 to 26,000, even more preferably 10,500 or more, 11,000 or more, particularly 11,500 or more, most preferably 12,000 or more, even more preferably 24,000 or less, and particularly preferably 20,000 or less. By setting the viscosity-average molecular weight to be above the lower limit of the above range, the mechanical strength of the polycarbonate resin composition of the present invention can be further improved, and by setting the viscosity-average molecular weight to be below the upper limit of the above range, the decrease in fluidity of the polycarbonate resin composition of the present invention can be suppressed and improved, thereby enhancing moldability and facilitating molding. Furthermore, two or more polycarbonate resins with different viscosity-average molecular weights may be mixed and used. In this case, polycarbonate resins whose viscosity-average molecular weight is outside the preferred range described above may also be mixed.

[0026] The viscosity-average molecular weight [Mv] is calculated by using methylene chloride as the solvent, determining the intrinsic viscosity [η] (unit: dl / g) at 25°C using an Ubbelohde viscometer, and then using Schnell's viscosity formula, i.e., η = 1.23 × 10⁻⁶. -4 Mv 0.83 It refers to the value calculated from [the formula]. In addition, intrinsic viscosity [η] is the specific viscosity [η] at each solution concentration [C] (g / dl). sp This value was calculated by measuring [the value] and using the following formula.

number

[0027] Furthermore, in order to improve the appearance and fluidity of the molded article, the polycarbonate resin (A) may contain polycarbonate oligomers. The viscosity-average molecular weight [Mv] of these polycarbonate oligomers is usually 1500 or more, preferably 2000 or more, and usually 9500 or less, preferably 9000 or less. Moreover, it is preferable that the amount of polycarbonate oligomers contained be 30% by mass or less of the polycarbonate resin (including the polycarbonate oligomers).

[0028] Furthermore, the polycarbonate resin (A) may be made not only from virgin raw materials but also from polycarbonate resin recycled from used products (so-called material-recycled polycarbonate resin), and it is also preferable to contain both virgin raw materials and recycled resin, or to consist solely of recycled polycarbonate resin. The proportion of recycled polycarbonate resin in the polycarbonate resin (A) is preferably 40% or more, 50% or more, 60% or more, or 80% or more, and is particularly preferable to be 100%.

[0029] [Graft copolymer (B)] The graft copolymer (B) contained in the polycarbonate resin composition of the present invention is a graft copolymer comprising an aromatic vinyl monomer component (b1), a vinyl cyanide monomer component (b2), and a diene-based rubber polymer component (b3). Preferably, the graft copolymer (B) consists of 40 to 80% by mass of the aromatic vinyl monomer component (b1), 10 to 30% by mass of the vinyl cyanide monomer component (b2), and 10 to 50% by mass of the diene-based rubber polymer component (b3), and may also contain 0 to 30% by mass of other monomer components (b4).

[0030] Examples of aromatic vinyl monomer components (b1) in the graft copolymer (B) include styrene, α-methylstyrene, o-methylstyrene, p-methylstyrene, vinylxylene, ethylstyrene, dimethylstyrene, pt-butylstyrene, vinylnaphthalene, methoxystyrene, monobromstyrene, dibromstyrene, fluorostyrene, tribromstyrene, etc., with styrene being particularly preferred. The proportion of aromatic vinyl monomer component (b1) in the graft copolymer (B) is preferably in the range of 40 to 80% by mass, more preferably 45% by mass or more, even more preferably 50% by mass or more, particularly preferably 55% by mass or more, more preferably 75% by mass or less, even more preferably 70% by mass or less, and particularly preferably 65% ​​by mass or less, based on 100% by mass of the graft copolymer (B).

[0031] Examples of vinyl cyanide monomer components (b2) in the graft copolymer (B) include acrylonitrile and methacrylonitrile, with acrylonitrile being particularly preferred. The proportion of the vinyl cyanide monomer component (b2) in the graft copolymer (B) is preferably in the range of 10 to 30% by mass, more preferably 12% by mass or more, even more preferably 14% by mass or more, particularly preferably 15% by mass or more, more preferably 28% by mass or less, even more preferably 26% by mass or less, and particularly preferably 25% by mass or less, based on 100% by mass of the graft copolymer (B).

[0032] As the diene-based rubber polymer component (b3) of the graft copolymer (B), for example, rubber components such as polybutadiene, polyisoprene, and styrene-butadiene copolymer can be used, and the proportion of the diene-based rubber polymer component (b3) in the graft copolymer (B) is preferably in the range of 10 to 50% by mass, more preferably 13% by mass or more, even more preferably 14% by mass or more, particularly preferably 15% by mass or more, and more preferably 45% by mass or less, based on 100% by mass of the graft copolymer (B).

[0033] Furthermore, copolymers with other monomer components (b4) that can copolymerize with these may also be used. In this case, examples of other copolymerizable vinyl monomers include maleimide monomers such as maleimide, N-methylmaleimide, N-cyclohexylmaleimide, and N-phenylmaleimide; acrylamide monomers such as acrylamide and N-methylacrylamide; unsaturated anhydrides such as maleic anhydride and itaconic anhydride; unsaturated acids such as acrylic acid and methacrylic acid; glycidyl acrylate, glycidyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, and methoxypolyethylene glycol methacrylate. The proportion of other monomer components (b4) in the graft copolymer (B) is preferably in the range of 0 to 30% by mass, more preferably 20% by mass or less, even more preferably 10% by mass or less, most preferably 5% by mass or less, especially 3% by mass or less, and most preferably 2% by mass or less, based on 100% by mass of the graft copolymer (B).

[0034] Specific examples of the graft copolymer (B) include acrylonitrile-butadiene-styrene graft copolymer, acrylonitrile-butadiene-styrene-α-methylstyrene graft copolymer, and acrylonitrile-ethylene-propylene-diene-styrene copolymer, among which acrylonitrile-butadiene-styrene graft copolymer (ABS resin) is particularly preferred.

[0035] Graft copolymers (B) are typically produced by methods such as bulk polymerization, solution polymerization, suspension polymerization, and emulsion polymerization, and any of these methods can be used.

[0036] The content of graft copolymer (B) is 10 to 45% by mass, based on 100% by mass of the total of polycarbonate resin (A) and graft copolymer (B), preferably 12% by mass or more, more preferably 15% by mass or more, preferably 42% by mass or less, and more preferably 40% by mass or less. Having the content within this range allows for excellent heat resistance and fluidity of the resin composition. If the amount of graft copolymer (B) exceeds 45% by mass, the heat resistance decreases, and if it is less than 10% by mass, the fluidity decreases.

[0037] [Trialyl phosphate (C)] The polycarbonate resin composition of the present invention contains a triaryl phosphate (C) represented by general formula (1). Here, the aryl group refers to a group containing an aromatic group, and particularly preferably a phenyl group. [ka]

[0038] In formula (1), R 1 ~R 5 Each of these is independently either a hydrogen atom or an alkyl group having 1 to 12 carbon atoms. Among the alkyl groups having 1 to 12 carbon atoms, alkyl groups having 1 to 8 carbon atoms are preferred, such as methyl, ethyl, propyl, n-butyl, t-butyl, pentyl, hexyl, heptyl, or octyl groups. Among these, alkyl groups having 1 to 6 carbon atoms are preferred, and alkyl groups having 1 to 4 carbon atoms are particularly preferred.

[0039] In equation (1), the R on the three aromatic rings 1 ~R 5 If two or more of the elements are alkyl groups, these alkyl groups may be the same or they may be different from each other. As for the triaryl phosphate (C), in formula (1), R on each aromatic ring 1 ~R 5 Preferably, at least one of them is an alkyl group having 1 to 12 carbon atoms. Furthermore, R on each aromatic ring 1 , R3 The R is an alkyl group having 1 to 12 carbon atoms, and each aromatic ring has R 2 , R 4 and R 5 It is more preferable that it be a hydrogen atom.

[0040] Specific examples of triaryl phosphates (C) include triphenyl phosphate, tricresyl phosphate, trixylenyl phosphate, cresyl diphenyl phosphate, cresyl-2,6-dixylenyl phosphate, dicresylphenyl phosphate, ethylphenyl diphenyl phosphate, diethylphenylphenyl phosphate, propylphenyl diphenyl phosphate, dipropylphenylphenyl phosphate, tripropylphenyl phosphate, butylphenyl diphenyl phosphate, dibutylphenylphenyl phosphate, tributylphenyl phosphate, and the like.

[0041] Triaryl phosphate (C) is preferably triphenyl phosphate or tris(4-t-butylphenyl) phosphate, and in formula (1), R on each aromatic ring 1 , R 3 The t-butyl group is located on each aromatic ring. 2 , R 4 and R 5 Preferably, the atom is a hydrogen atom, and tris(2,4-di-t-butylphenyl) phosphate is particularly preferred.

[0042] Triaryl phosphate (C) may be used alone or in combination of two or more types.

[0043] The content of triaryl phosphate (C) is 0.001 to 0.3 parts by mass per 100 parts by mass of the total of the polycarbonate resin (A) and the graft copolymer (B). Resin compositions containing this amount together with a predetermined amount of compound (D) having a phenolic structure exhibit excellent weather resistance and excellent hue. The content of triaryl phosphate (C) is preferably 0.002 parts by mass or more, more preferably 0.003 parts by mass or more, 0.004 parts by mass or more, particularly preferably 0.005 parts by mass or more, and also preferably 0.25 parts by mass or less, more preferably 0.2 parts by mass or less, 0.15 parts by mass or less, 0.13 parts by mass or less, particularly preferably 0.1 parts by mass or less.

[0044] [Compounds having a phenolic structure (D)] The polycarbonate resin composition of the present invention contains a compound (D) having a phenolic structure. Compound (D) having a phenolic structure is a compound in which a hydroxyl group is directly bonded to a benzene ring, and in the present invention, these are 4-t-butylphenol, 2,4-di-t-butylphenol, 4-α-cumylphenol, and bisphenol A. Among these, 4-t-butylphenol, 4-α-cumylphenol, and 4-t-butylphenol are more preferred. The compound (D) having a phenolic structure may be present as a single compound or as two or more compounds.

[0045] The content of compound (D) having a phenolic structure is 0.001 to 0.03 parts by mass per 100 parts by mass of the total of polycarbonate resin (A) and graft copolymer (B). If two or more compounds having a phenolic structure (D1) are included, the total amount of these compounds is used. A resin composition containing polycarbonate resin (A) and graft copolymer (B) together with triaryl phosphate (C) in such amounts exhibits excellent weather resistance, as well as superior impact resistance, heat resistance, and fluidity (moldability).

[0046] The content of compound (D) having a phenolic structure is preferably 0.0015 parts by mass or more, more preferably 0.002 parts by mass or more, 0.003 parts by mass or more, particularly preferably 0.004 parts by mass or more, and also preferably 0.025 parts by mass or less, more preferably 0.02 parts by mass or less, particularly preferably 0.015 parts by mass or less, particularly preferably 0.013 parts by mass or less, based on 100 parts by mass of the total of polycarbonate resin (A) and graft copolymer (B).

[0047] When 4-t-butylphenol is included as the 47 compound (D) having a phenolic structure, the content is preferably 0.0012 to 0.01 parts by mass, and more preferably 0.002 to 0.003 parts by mass, per 100 parts by mass of the total of (A) and (B). When compound (D) having a phenolic structure contains 2,4-di-t-butylphenol, the content is preferably 0.0012 to 0.01 parts by mass, and more preferably 0.002 to 0.003 parts by mass, based on 100 parts by mass of the total of (A) and (B). If 4-α-cumylphenol is included, the content is preferably 0.0012 to 0.01 parts by mass, more preferably 0.002 to 0.003 parts by mass, per 100 parts by mass of the total of (A) and (B). When bisphenol A is included as compound (D) having a phenolic structure, the content is preferably 0.002 to 0.03 parts by mass, more preferably 0.004 to 0.01 parts by mass, based on 100 parts by mass of the total of (A) and (B).

[0048] 4-t-butylphenol, 2,4-di-t-butylphenol, 4-α-cumylphenol, or bisphenol A may be present in a free state, either used or produced as a by-product during the manufacture of polycarbonate resin (A), or derived from recycled polycarbonate resin, and these amounts are also included as part of the amount of compound (D) having a phenolic structure.

[0049] [Triarylphosphite (E)] The polycarbonate resin composition of the present invention may further preferably contain triaryl phosphite (E). Here, the aryl group refers to a group containing a monocyclic or polycyclic aromatic group, and particularly preferably a phenyl group.

[0050] Examples of preferred triaryl phosphites (E) include triphenyl phosphite, tris(p-tolyl) phosphite, tris(p-nonylphenyl) phosphite, tris(mononyl / dinonylphenyl) phosphite, tris(2,4-di-t-butylphenyl) phosphite, tris(naphthyl) phosphite, tris(p-chlorophenyl) phosphite, tris(p-fluorophenyl) phosphite, diphenylbenzylphosphine, diphenyl(p-hydroxyphenyl) phosphite, diphenyl-1,4-dihydroxyphenyl-2-phosphite, and phenylnaphthylbenzylphosphine, with triphenyl phosphite and tris(2,4-di-t-butylphenyl) phosphite being particularly preferred.

[0051] When triaryl phosphite (E) is included, its content is preferably 0.001 to 0.3 parts by mass per 100 parts by mass of the total of the polycarbonate resin (A) and the graft copolymer (B). Resin compositions containing triaryl phosphite (C) in such amounts exhibit superior hue. The arylphosphine content is more preferably 0.005 parts by mass or more, more preferably 0.008 parts by mass or more, particularly preferably 0.01 parts by mass or more, and more preferably 0.25 parts by mass or less, particularly preferably 0.2 parts by mass or less, 0.15 parts by mass or less, 0.1 parts by mass or less, 0.05 parts by mass or less, and particularly preferably 0.04 parts by mass or less.

[0052] [Phenol-based antioxidants] The polycarbonate resin composition of the present invention may also preferably contain a phenolic antioxidant. As a phenolic antioxidant, hindered phenolic antioxidants are preferred, for example. Specific examples include pentaerythritol tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate, thiodiethylenebis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], N,N'-hexane-1,6-diylbis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionamide], 2,4-dimethyl-6-(1-methylpentadecyl)phenol, diethyl[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]methyl]phosphoate, 3,3',3”,5,5',5”-hexa-t-butyl-a,a',a”-(mesitylene-2,4, Examples include 6-triyl)tri-p-cresol, 4,6-bis(octylthiomethyl)-o-cresol, ethylenebis(oxyethylene)bis[3-(5-t-butyl-4-hydroxy-m-tolyl)propionate], hexamethylenebis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], 1,3,5-tris(3,5-di-t-butyl-4-hydroxybenzyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, 2,6-di-t-butyl-4-(4,6-bis(octylthio)-1,3,5-triazine-2-ylamino)phenol, and 2-[1-(2-hydroxy-3,5-di-t-pentylphenyl)ethyl]-4,6-di-t-pentylphenyl acrylate.

[0053] Among these, pentaerythritol tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate] and octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate are particularly preferred. Furthermore, the phenolic antioxidant may be present in any single form, or in any combination and ratio of two or more forms.

[0054] When a phenolic antioxidant is included, its content is preferably 0.001 parts by mass or more, more preferably 0.01 parts by mass or more, and preferably 1 part by mass or less, more preferably 0.5 parts by mass or less, per 100 parts by mass of the total of the polycarbonate resin (A) and the graft copolymer (B). By setting the content of the phenolic antioxidant to be above the lower limit of the above range, the effect of the phenolic antioxidant can be sufficiently obtained. Furthermore, by setting the content of the phenolic antioxidant to be below the upper limit of the above range, the effect does not plateau, making it economical.

[0055] [Release agent] The resin composition of the present invention may also preferably contain a mold release agent. Examples of release agents include aliphatic carboxylic acids, esters of aliphatic carboxylic acids and alcohols, aliphatic hydrocarbon compounds with a number average molecular weight of 200 to 15,000, and polysiloxane-based silicone oils.

[0056] Examples of aliphatic carboxylic acids include saturated or unsaturated aliphatic monovalent, divalent, or trivalent carboxylic acids. Here, aliphatic carboxylic acids also include alicyclic carboxylic acids. Among these, preferred aliphatic carboxylic acids are monovalent or divalent carboxylic acids having 6 to 36 carbon atoms, and more preferably aliphatic saturated monovalent carboxylic acids having 6 to 36 carbon atoms. Specific examples of such aliphatic carboxylic acids include palmitic acid, stearic acid, caproic acid, capric acid, lauric acid, arachidic acid, behenic acid, lignoceric acid, cerotic acid, melissic acid, tetrariacontanoic acid, montanic acid, adipic acid, and azelaic acid.

[0057] As the aliphatic carboxylic acid in the ester of an aliphatic carboxylic acid and an alcohol, for example, the same aliphatic carboxylic acid as described above can be used. On the other hand, as the alcohol, for example, saturated or unsaturated monohydric or polyhydric alcohols can be used. These alcohols may have substituents such as fluorine atoms or aryl groups. Among these, monohydric or polyhydric saturated alcohols having 30 or fewer carbon atoms are preferred, and aliphatic saturated monohydric alcohols or aliphatic saturated polyhydric alcohols having 30 or fewer carbon atoms are more preferred. Here, "aliphatic" is used as a term that also includes alicyclic compounds.

[0058] Specific examples of such alcohols include octanol, decanol, dodecanol, stearyl alcohol, behenyl alcohol, ethylene glycol, diethylene glycol, glycerin, pentaerythritol, 2,2-dihydroxyperfluoropropanol, neopentylene glycol, ditrimethylolpropane, and dipentaerythritol.

[0059] Furthermore, the above-mentioned esters may contain aliphatic carboxylic acids and / or alcohols as impurities. Also, the above-mentioned esters may be pure substances or mixtures of multiple compounds. Moreover, the aliphatic carboxylic acids and alcohols that combine to form a single ester may be used individually, or two or more may be used in any combination and ratio.

[0060] Specific examples of esters of aliphatic carboxylic acids and alcohols include beeswax (a mixture mainly composed of myricyl palmitate), stearyl stearate, behenyl behenate, stearyl behenate, glycerin monopalmitate, glycerin monostearate, glycerin distearate, glycerin tristearate, pentaerythritol monopalmitate, pentaerythritol monostearate, pentaerythritol distearate, pentaerythritol tristearate, and pentaerythritol tetrastearate.

[0061] Aliphatic hydrocarbons with a number-average molecular weight of 200 to 15,000 include, for example, liquid paraffin, paraffin wax, microwax, polyethylene wax, Fischer-Tropsch wax, and α-olefin oligomers having 3 to 12 carbon atoms. Note that alicyclic hydrocarbons are also included in the definition of aliphatic hydrocarbons. Furthermore, these hydrocarbons may be partially oxidized. Among these, paraffin wax, polyethylene wax, or partially oxided polyethylene wax are preferred, and paraffin wax and polyethylene wax are more preferred. Furthermore, the number-average molecular weight of the aliphatic hydrocarbon is preferably 5000 or less. Furthermore, while aliphatic hydrocarbons may be single substances, mixtures of substances with varying constituent components and molecular weights can also be used as long as the main component falls within the above-mentioned range.

[0062] Examples of polysiloxane-based silicone oils include dimethyl silicone oil, methylphenyl silicone oil, diphenyl silicone oil, and fluorinated alkyl silicone.

[0063] Furthermore, the above-mentioned release agent may contain one type, or two or more types in any combination and ratio.

[0064] The release agent content is typically 0.001 parts by mass or more, preferably 0.01 parts by mass or more, and typically 2 parts by mass or less, preferably 1 part by mass or less, and more preferably 0.5 parts by mass or less, per 100 parts by mass of the total of the polycarbonate resin (A) and the graft copolymer (B). If the release agent content is below the lower limit of the above range, the release effect may not be sufficient, and if the release agent content exceeds the upper limit of the above range, a decrease in hydrolysis resistance and mold contamination during injection molding may occur.

[0065] [UV absorber] The polycarbonate resin composition of the present invention may also preferably contain an ultraviolet absorber. Examples of UV absorbers include inorganic UV absorbers such as cerium oxide and zinc oxide; and organic UV absorbers such as benzotriazole compounds, benzophenone compounds, salicylate compounds, cyanoacrylate compounds, triazine compounds, oxanilide compounds, malonic acid ester compounds, and hindered amine compounds. Among these, organic UV absorbers are preferred, and benzotriazole compounds are more preferred. By selecting an organic UV absorber, the transparency and mechanical properties of the resin composition of the present invention are improved.

[0066] Specific examples of benzotriazole compounds include, for example, 2-(2'-hydroxy-5'-methylphenyl)benzotriazole, 2-[2'-hydroxy-3',5'-bis(α,α-dimethylbenzyl)phenyl]-benzotriazole, 2-(2'-hydroxy-3',5'-di-t-butyl-phenyl)-benzotriazole, 2-(2'-hydroxy-3'-t-butyl-5'-methylphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-3',5'-di-t-butyl-phenyl)-5-chlorobenzotriazole), and 2-(2'-hydroxy-3',5'-di-t- Examples include amyl)-benzotriazole, 2-(2'-hydroxy-5'-t-octylphenyl)benzotriazole, and 2,2'-methylenebis[4-(1,1,3,3-tetramethylbutyl)-6-(2H-benzotriazole-2-yl)phenol], among which 2-(2'-hydroxy-5'-t-octylphenyl)benzotriazole and 2,2'-methylenebis[4-(1,1,3,3-tetramethylbutyl)-6-(2H-benzotriazole-2-yl)phenol] are preferred, and 2-(2'-hydroxy-5'-t-octylphenyl)benzotriazole is particularly preferred.

[0067] Specific examples of benzophenone compounds include, for example, 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid, 2-hydroxy-4-n-octoxybenzophenone, 2-hydroxy-n-dodecyloxybenzophenone, bis(5-benzoyl-4-hydroxy-2-methoxyphenyl)methane, 2,2'-dihydroxy-4-methoxybenzophenone, and 2,2'-dihydroxy-4,4'-dimethoxybenzophenone.

[0068] Specific examples of salicylate compounds include, for example, phenyl salicylate and 4-t-butylphenyl salicylate. Specific examples of cyanoacrylate compounds include, for example, ethyl-2-cyano-3,3-diphenylacrylate and 2-ethylhexyl-2-cyano-3,3-diphenylacrylate. Specific examples of oxanilide compounds include, for example, 2-ethoxy-2'-ethyloxalic acid bisarilinide. As the malonic acid ester compound, 2-(alkylidene)malonic acid esters are preferred, and 2-(1-arylalkylidene)malonic acid esters are more preferred.

[0069] When an ultraviolet absorber is included, its content is usually 0.05 parts by mass or more, preferably 0.1 parts by mass or more, and usually 1 part by mass or less, preferably 0.5 parts by mass or less, per 100 parts by mass of the total of the polycarbonate resin (A) and the graft copolymer (B). If the content of the ultraviolet absorber is below the lower limit of the above range, the improvement effect on weather resistance and light resistance may be insufficient, and if the content of the ultraviolet absorber exceeds the upper limit of the above range, mold deposits and the like may occur, causing mold contamination. The ultraviolet absorber may contain one type, or two or more types in any combination and ratio.

[0070] [Additives, etc.] The polycarbonate resin composition of the present invention may contain other additives besides those mentioned above, such as fluorescent whitening agents, pigments (including titanium dioxide, etc.), dyes, flame retardants, impact modifiers, plasticizers, and compatibilizers. These additives may be present one or more types.

[0071] Furthermore, the material may contain other resins besides polycarbonate resin (A) and graft copolymer (B). Examples of other resins include thermoplastic polyester resins such as polyethylene terephthalate, polytrimethylene terephthalate, and polybutylene terephthalate; styrene-based resins such as polystyrene resin (GPPS), high-impact polystyrene resin (HIPS), and acrylonitrile-styrene copolymer (AS resin); polyolefin resins such as polyethylene resin and polypropylene resin; polyamide resin; polyimide resin; polyetherimide resin; polyurethane resin; polyphenylene ether resin; polyphenylene sulfide resin; polysulfone resin; and polymethacrylate resin. When other resins are included besides the polycarbonate resin (A) and the graft copolymer (B), the content of these other resins is preferably 20 parts by mass or less, more preferably 10 parts by mass or less, and even more preferably 5 parts by mass or less, and particularly preferably 3 parts by mass or less, based on 100 parts by mass of the total of the polycarbonate resin (A) and the graft copolymer (B). [Examples]

[0072] In order to confirm the effects of the polycarbonate resin composition of the present invention, the polycarbonate resin composition was prepared and manufactured as follows, but the present invention is not limited to the following examples. The ingredients used are as shown in Table 1 below.

[0073] [Table 1]

[0074] (Examples 1-17, Comparative Examples 1-8) Each of the above-mentioned components was blended in the proportions (parts by mass) shown in Table 2 and below, supplied to a twin-screw extruder (Toshiba Machine Co., Ltd. "TEM26SX"), and kneaded under the conditions of a screw rotation speed of 150 rpm, a discharge rate of 25 kg / hour, and a barrel temperature of 260°C. The mixture was then extruded in a strand shape from the tip of the extrusion nozzle. The strand was rapidly cooled in a water bath and cut into pellets using a pelletizer to obtain pellets of the polycarbonate resin composition.

[0075] <mvr> The pellets obtained by the above method were dried at 100°C for 5 hours, and then the MVR (Melt Volume Rate, unit: g / 10min) was measured in accordance with ISO 1133 under conditions of a measurement temperature of 250°C and a load of 2.16 kgf.

[0076] <Charpy strength with notch> The pellets obtained by the above method were dried at 100°C for 5 hours, and then injection molded using an injection molding machine (NEX80III, manufactured by Nissei Plastic Industrial Co., Ltd.) under conditions of cylinder temperature of 260°C and mold temperature of 60°C to produce ISO multipurpose test specimens (4mm thick). Using the obtained ISO multipurpose test specimen (4mm thick), the notched Charpy strength (unit: kJ / m²) was measured at 23°C according to ISO standard 179. 2 ) was measured.

[0077] <Heat resistance DTUL (temperature of deflection under load)> Based on ISO 75-1 and ISO 75-2, a constant bending load (1.80 MPa) was applied to the center of a 4 mm x 10 mm ISO multipurpose test specimen (4 mm thick) in the flatwise direction, and the temperature was increased at a constant rate. The temperature (in °C) when the strain in the center reached 0.34 mm was measured.

[0078] <Weather resistance (ΔE)> The obtained pellets were injection molded using a Toshiba Machine Co., Ltd. injection molding machine "EC50SXII" under conditions of cylinder temperature 260°C and mold temperature 60°C to obtain a plate-shaped molded product measuring 90 mm in length, 60 mm in width, and 2 mm in thickness. The resulting plate-shaped molded product was subjected to xenon weathering using a xenon weathering machine (ATLAS Corporation, "Ci4000") with light at a wavelength of 300-400 nm, at a temperature of 89°C and an irradiation intensity of approximately 55 W / m². 2 Lightfastness treatment was performed under the condition of a processing time of 100 hours (300 hours for titanium dioxide-added systems). The hue before and after lightfastness treatment was measured using Nippon Denshoku Industries' "SE6000" under D65, 10° field of view, and reflection conditions, and the color difference ΔE was calculated to evaluate the lightfastness. ΔE is preferably 7.5 or less. In the case of a titanium dioxide-added system, it is preferably 1.4 or less.

[0079] The evaluation results are shown in Table 2 and below.

[0080] [Table 2]

[0081] [Table 3]

[0082] [Table 4]

[0083] [Table 5]

[0084] [Table 6] [Industrial applicability]

[0085] The polycarbonate resin composition of the present invention has high weather resistance and excellent impact resistance, heat resistance, and fluidity (moldability), making it suitable for use in various molded products.< / mvr>

Claims

1. A total of 100 parts by mass of (A) and (B) containing 55 to 90% by mass of a polycarbonate resin (A) having a viscosity-average molecular weight of 17,500 to 30,000, and 10 to 45% by mass of a graft copolymer (B) containing an aromatic vinyl monomer component (b1), a vinyl cyanide monomer component (b2), and a diene-based rubbery polymer component (b3), It contains 0.001 to 0.3 parts by mass of a triaryl phosphate (C) represented by the following general formula (1), and 0.001 to 0.3 parts by mass of a compound (D) having a phenol structure. A polycarbonate resin composition characterized in that compound (D) having a phenolic structure contains at least one of 4-t-butylphenol, 2,4-di-t-butylphenol, 4-α-cumylphenol, and bisphenol A. 【Chemistry 1】 [In formula (1), R １ ~R ５ These are, independently, a hydrogen atom and an alkyl group having 1 to 12 carbon atoms.

2. In formula (1), R on each aromatic ring １ ~R ５ The polycarbonate resin composition according to claim 1, wherein at least one of the members is an alkyl group having 1 to 12 carbon atoms.

3. In formula (1), R on each aromatic ring １ , R ３ is an alkyl group having 1 to 12 carbon atoms, and R on each aromatic ring ２ , R ４ and R ５ are hydrogen atoms. The polycarbonate resin composition according to claim 1.

4. In formula (1), R on each aromatic ring １ , R ３ The group is a t-butyl group, and the R on each aromatic ring ２ , R ４ and R ５ The polycarbonate resin composition according to claim 3, wherein is a hydrogen atom.

5. The polycarbonate resin composition according to claim 1, wherein the triaryl phosphate (C) contains at least one of triphenyl phosphate, tris-2,4-di-t-butyl phosphate, and tris-4-t-butyl phosphate.

6. The polycarbonate resin composition according to claim 1, further comprising 0.001 to 0.3 parts by mass of triaryl phosphite (E) with respect to 100 parts by mass of the total of (A) and (B).

7. Pellets of the polycarbonate resin composition according to any one of claims 1 to 6.

8. A molded article comprising the polycarbonate resin composition according to any one of claims 1 to 6.

9. A molded article comprising pellets of the polycarbonate resin composition described in claim 7.

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