Flame-retardant polycarbonate resin composition

Abstract

A flame-retardant polycarbonate resin composition that complies with PFAS regulations, is environmentally friendly, and possesses extremely high flame retardancy. [Solution] A flame-retardant polycarbonate resin composition characterized by containing 0.04 to 0.7 parts by mass of an organic sulfonic acid-based flame retardant (B) that does not contain fluorine atoms, per 100 parts by mass of polycarbonate resin (A) containing 30 to 60 parts by mass of a linear aromatic polycarbonate resin (A1) with a viscosity-average molecular weight of 10,000 to 25,000, 10 to 30 parts by mass of a linear aromatic polycarbonate resin (A2) with a viscosity-average molecular weight of 50,000 to 90,000, and 20 to 60 parts by mass of a branched aromatic polycarbonate (A3) with a viscosity-average molecular weight of 25,000 to 40,000.

Description

Technical Field

[0001] The present invention relates to a flame-retardant polycarbonate resin composition, and more particularly, to a flame-retardant polycarbonate resin composition that clears PFAS regulations and is an environmentally considerate material while having a high degree of flame retardancy.

Background Art

[0002] Polycarbonate resin is a resin excellent in heat resistance, mechanical properties, and electrical properties, and is widely used, for example, as a material for manufacturing parts in vehicle parts, electrical and electronic equipment parts, housing members, and other industrial fields. In particular, flame-retardant polycarbonate resin compositions are suitably used as parts such as vehicle parts, electrical and electronic equipment parts such as personal computers, mobile phones, battery cases, and parts of OA and information equipment such as printers and copiers.

[0003] In recent years, the trend towards flame retardancy has increased, and a high degree of flame retardancy has been required for polycarbonate resins. In many cases, V-0 products according to the UL-94 test method are required. As a means of imparting flame retardancy to polycarbonate resins, halogen-based flame retardants and phosphorus-based flame retardants have been used. However, in order to exhibit V-0 flame retardant performance with a phosphorus-based flame retardant, a relatively large addition rate is required, which easily reduces the mechanical properties of polycarbonate resin materials. Flame retardancy using halogen-based bromine-based or chlorine-based flame retardants has been subject to strengthened regulations on use bans due to toxicity and environmental problems caused by the generation of harmful gases.

[0004] In particular, fluorine-based flame retardants typified by perfluoroalkane metal salts proposed in Patent Documents 1 and 2 enable a high degree of flame retardancy with a relatively small amount of blending. In addition, by blending such a flame retardant together with a polyfluoroethylene such as PTFE as a dripping inhibitor, dripping can be suppressed and the flame retardancy can be further improved. However, in recent years, fluorine compounds have become subject to international regulations, primarily in Japan, Europe, and the United States. PFAS regulations targeting perfluoroalkyl and polyfluoroalkyl compounds are progressing, mainly in the EU and the US, and polyfluoroethylenes are also included. PFAS regulations are being further strengthened internationally. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Special Publication No. 47-40445 [Patent Document 2] Japanese Patent Application Publication No. 49-88943 [Overview of the project] [Problems that the invention aims to solve]

[0006] Therefore, there is a strong demand for high-performance flame-retardant polycarbonate resin compositions that do not generate toxic gases during combustion, meet PFAS regulations, and are environmentally friendly. However, achieving UL-94 V-0 with non-halogenated flame retardants or non-phosphorus flame retardants, or without using polytetrafluoroethylene as a dripping inhibitor in combination with them, is by no means easy. This invention has been made in view of the above circumstances, and its objective (problem) is to provide a polycarbonate resin composition that complies with PFAS regulations and exhibits high-performance flame retardancy while being environmentally friendly. [Means for solving the problem]

[0007] The inventors, after diligent research to achieve the above objectives, discovered that by combining specific amounts of linear aromatic polycarbonate resin with a viscosity-average molecular weight of 10,000 to 25,000, linear aromatic polycarbonate resin with a viscosity-average molecular weight of 50,000 to 90,000, and branched aromatic polycarbonate with a viscosity-average molecular weight of 25,000 to 40,000, and blending this with an organic sulfonic acid-based flame retardant that does not contain fluorine atoms, it is possible to achieve extremely high flame retardancy at the V-0 level in the UL94 test at a thickness of 1.5 mm, thus completing the present invention. This invention relates to the following flame-retardant polycarbonate resin compositions and molded articles.

[0008] 1. A flame-retardant polycarbonate resin composition characterized by containing 0.04 to 0.7 parts by mass of an organic sulfonic acid-based flame retardant (B) that does not contain fluorine atoms, per 100 parts by mass of polycarbonate resin (A), which contains 30 to 60 parts by mass of a linear aromatic polycarbonate resin (A1) with a viscosity-average molecular weight of 10,000 to 25,000, 10 to 30 parts by mass of a linear aromatic polycarbonate resin (A2) with a viscosity-average molecular weight of 50,000 to 90,000, and 20 to 60 parts by mass of a branched aromatic polycarbonate (A3) with a viscosity-average molecular weight of 25,000 to 40,000. 2. The polycarbonate resin composition according to item 1 above, which does not contain perfluoroalkyl compounds (PFAS) and has a fluorine content of less than 100 ppm by mass as measured by combustion ion chromatography. 3. The polycarbonate resin composition according to 1 or 2 above, which does not contain fluorine atoms in the resin composition. 4. The polycarbonate resin composition according to any one of 1 to 3 above, wherein the organic sulfonic acid-based flame retardant (B) that does not contain fluorine atoms is one or more of the following: p-toluenesulfonic acid or its metal salt, or phenylsulfonylbenzenesulfonic acid or its metal salt. 5. A polycarbonate resin composition according to any one of the above 1 to 4, further containing a silicone-based flame retardant additive (C) in an amount of 0.1 to 2.0 parts by mass per 100 parts by mass of polycarbonate resin (A). 6. A polycarbonate resin composition according to any one of items 1 to 5 above, wherein the UL-94 rating at a thickness of 6.1.5 mm is V-0. 7. Pellets of the polycarbonate resin composition described in any of items 1 to 6 above. 8. A molded article of the polycarbonate resin composition described in any of items 1 to 6 above. 9. Molded product of the pellets described in item 7 above. [Effects of the Invention]

[0009] The polycarbonate resin composition of the present invention complies with PFAS regulations and is an environmentally friendly material, while also possessing extremely high flame retardancy, achieving a V-0 rating in the UL94 test at a thickness of 1.5 mm, and further exhibiting excellent heat retention stability and resistance to humid heat. [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 flame-retardant polycarbonate resin composition of the present invention is characterized by containing 0.04 to 0.7 parts by mass of an organic sulfonic acid-based flame retardant (B) that does not contain fluorine atoms, per 100 parts by mass of polycarbonate resin (A), which contains 30 to 60 parts by mass of a linear aromatic polycarbonate resin (A1) with a viscosity-average molecular weight of 10,000 to 25,000, 10 to 30 parts by mass of a linear aromatic polycarbonate resin (A2) with a viscosity-average molecular weight of 50,000 to 90,000, and 20 to 60 parts by mass of a branched aromatic polycarbonate (A3) with a viscosity-average molecular weight of 25,000 to 40,000.

[0012] [Polycarbonate resin (A)] The polycarbonate resin (A), which is component (A) of the present invention, contains a linear aromatic polycarbonate resin (A1) with a viscosity-average molecular weight of 10,000 to 25,000, a linear aromatic polycarbonate resin (A2) with a viscosity-average molecular weight of 50,000 to 90,000, and a branched aromatic polycarbonate (A3) with a viscosity-average molecular weight of 25,000 to 40,000.

[0013] <Linear aromatic polycarbonate resin (A1)> The aromatic polycarbonate resin (A1) is a linear aromatic polycarbonate resin with a viscosity-average molecular weight (Mv) of 10,000 to 25,000. The viscosity-average molecular weight (Mv) is preferably 11,000 or more, more preferably 12,000 or more, particularly preferably 13,000 or more, preferably 24,000 or less, and more preferably 23,000 or less. The aromatic polycarbonate resin (A1) may be a single type, or a mixture of two or more polycarbonate resins may be used. When mixing two or more types with different Mv values, it is preferable to mix polycarbonate resins whose Mv values ​​fall within the above range, but it is also possible to add a polycarbonate resin (A2) with an Mv value of 50,000 or higher to adjust the Mv value to fall within the above range. However, when adding a polycarbonate resin (A1) with an Mv value outside the above range, the amount is preferably less than 15% by mass, more preferably less than 10% by mass, less than 7% by mass, less than 5% by mass, and especially less than 3% by mass, out of 100% by mass of the aromatic polycarbonate resin (A1).

[0014] [Linear aromatic polycarbonate resin (A2)] The aromatic polycarbonate resin (A2) is a linear aromatic polycarbonate resin with a viscosity-average molecular weight of 50,000 to 90,000. The viscosity-average molecular weight (Mv) of the polycarbonate resin (A2) is preferably 55,000 or more, more preferably 60,000 or more, most preferably 61,000 or more, and especially preferably 62,000 or more. It is also preferably 88,000 or less, most preferably 86,000 or less, 85,000 or less, 83,000 or less, 82,000 or less, 81,000 or less, and especially preferably 80,000 or less. The polycarbonate resin (A2) may be of one type, or two or more polycarbonate resins may be mixed and used. When two or more types are mixed and used, it is preferable to mix polycarbonate resins having an Mv within the above range. However, when mixing two or more types having different Mvs, those having an Mv outside the above range (excluding those having an Mv of 25,000 or less of the polycarbonate resin (A1)) can be added and adjusted so that the Mv falls within the above range for use. However, when adding those having an Mv outside the above range, the amount is preferably less than 15% by mass, particularly less than 10% by mass, less than 7% by mass, less than 5% by mass, and especially less than 3% by mass in 100% by mass of the polycarbonate resin (A2).

[0015] In the present invention, the viscosity-average molecular weight (Mv) of the polycarbonate resin is determined by using methylene chloride as a solvent and measuring the intrinsic viscosity [η] (unit: dl / g) at a temperature of 25°C using an Ubbelohde viscometer, and is calculated from the Schnell viscosity formula, that is, η = 1.23×10 -4 Mv 0.83 The intrinsic viscosity [η] is a value calculated by measuring the specific viscosity [η sp at each solution concentration [C] (g / dl) according to the following formula. [Equation]

[0016] The aromatic polycarbonate resins (A(1)) and (A(2)) are linear polycarbonate resins. The linear polycarbonate resin is preferably a polycarbonate resin obtained by an interfacial polymerization method of an aromatic dihydroxy compound and carbonyl chloride without using a branching agent. Those using a branching agent or polycarbonate resins by a melting method (transesterification method) are branched and not preferable.

[0017] [Branched aromatic polycarbonate (A3)] Branched aromatic polycarbonate (A3) is a branched aromatic polycarbonate resin with a viscosity-average molecular weight of 25,000 to 40,000. As an example of a preferred method for producing branched aromatic polycarbonates, as described in Japanese Patent Publication No. 8-259687 and Japanese Patent Publication No. 8-245782, a branched polycarbonate resin can be obtained without using a branching agent by selecting catalyst conditions or production conditions when reacting a dihydroxy compound with a diester of carbonic acid by melt transesterification.

[0018] Another preferred method for producing branched aromatic polycarbonate (A3) is to copolymerize a trifunctional or transesterification method using a polyfunctional compound (branching agent) with three or more functions, in addition to the dihydroxy compound and carbonate-forming compound which are raw materials for polycarbonate resin.

[0019] Examples of polyfunctional compounds with three or more functions include polyhydroxy compounds such as 1,3,5-trihydroxybenzene (phloroglucin), 4,6-dimethyl-2,4,6-tri(4-hydroxyphenyl)heptene-2,4,6-dimethyl-2,4,6-tri(4-hydroxyphenyl)heptane, 2,6-dimethyl-2,4,6-tri(4-hydroxyphenyl)heptene-3, 1,3,5-tri(4-hydroxyphenyl)benzene, and 1,1,1-tri(4-hydroxyphenyl)ethane; and 3,3-bis(4-hydroxyaryl)oxyindol (i.e., isatinbisphenol), 5-chloroisatin, 5,7-dichloroisatin, and 5-bromoisatin. Among these, 1,1,1-tri(4-hydroxyphenyl)ethane is preferred.

[0020] The amount of polyfunctional aromatic compound used is usually 0.01 mol% or more, preferably 0.1 mol% or more, and usually 10 mol% or less, preferably 3 mol% or less, relative to the total dihydroxy compounds of the raw materials. One polyfunctional compound may be used, or two or more may be used in any combination and ratio.

[0021] The branched aromatic polycarbonate (A3) preferably has a structural viscosity index N value of 1.20 or higher, more preferably 1.25 or higher, even more preferably 1.28 or higher, and more preferably 2.0 or lower, and more preferably 1.9 or lower. The structural viscosity index N-value of the linear aromatic polycarbonate resin (A1) and linear aromatic polycarbonate resin (A2) is preferably less than 1.20, more preferably 1.15 or less, even more preferably 1.10 or less, particularly preferably 1.05 or less, and usually 1.0 or higher. Such a small N-value means that the degree of branching of the polycarbonate resin is small and it is linear. Such branched aromatic polycarbonate (A3) is preferably produced by interfacial polymerization, as described above.

[0022] The structural viscosity index (N-value) is an index used to evaluate the flow properties of a molten material. Typically, the melting properties of polycarbonate resin can be expressed by the formula: γ = a·σN. Here, γ represents the shear rate, a is a constant, σ represents stress, and N represents the structural viscosity index. Furthermore, as described in Japanese Patent Publication No. 2005-232442, for example, it is also possible to express it using the formula Logηa = [(1-N) / N] × Logγ + C, which is derived from the above formula. Here, N represents the structural viscosity index, γ represents the shear rate, C represents a constant, and ηa represents the apparent viscosity.

[0023] The viscosity-average molecular weight Mv of the branched aromatic polycarbonate (A3) is, as described above, 25,000 to 40,000, but preferably 26,000 or more, more preferably 26,500 or more, preferably 39,000 or less, even more preferably 38,000 or less, and particularly preferably 37,000 or less. The branched aromatic polycarbonate (A3) may be a single type, or it may be a mixture of two or more polycarbonate resins. When mixing two or more types with different Mv values, it is preferable to mix branched aromatic polycarbonates whose Mv values ​​fall within the above range, but it is also possible to add branched aromatic polycarbonates whose Mv values ​​fall outside the above range to adjust the Mv value to fall within the above range. However, when adding a branched aromatic polycarbonate whose Mv values ​​fall outside the above range, the amount is preferably less than 15% by mass, more preferably less than 10% by mass, less than 7% by mass, less than 5% by mass, and especially less than 3% by mass, out of 100% by mass of the aromatic polycarbonate resin (A2).

[0024] The types of aromatic polycarbonate resins (A1) and (A2) are not particularly limited, and are aromatic polycarbonate resins in which the carbon atoms directly bonded to the carbonate bonds are aromatic carbon atoms.

[0025] 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;

[0026] 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;

[0027] 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;

[0028] 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-tert-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;

[0029] 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-tert-butyl-cyclohexane, 1,1-Bis(4-hydroxyphenyl)-4-tert-butyl-cyclohexane, 1,1-bis(4-hydroxyphenyl)-3-phenylcyclohexane, 1,1-Bis(4-hydroxyphenyl)-4-phenylcyclohexane, Bis(hydroxyaryl)cycloalkanes such as;

[0030] 9,9-Bis(4-hydroxyphenyl)fluorene, Bisphenols containing cardo structures, such as 9,9-bis(4-hydroxy-3-methylphenyl)fluorene;

[0031] 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.

[0032] 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.

[0033] Among the monomers used as raw materials for polycarbonate resin, examples of carbonate precursors include carbonyl halides. Note that one type of carbonate precursor may be used, or two or more types may be used in any combination and ratio.

[0034] Examples of carbonyl halides include, specifically, phosgene; bischloroformates of dihydroxy compounds; monochloroformates of dihydroxy compounds; and other haloformates.

[0035] 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.

[0036] <Method for manufacturing polycarbonate resin> The manufacturing method for polycarbonate resins (A1), (A2), and (A3) is not limited, and any known method can be used. Examples include interfacial polymerization, melt transesterification, pyridine method, ring-opening polymerization of cyclic carbonate compounds, and solid-phase transesterification of prepolymers. Among these, interfacial polymerization and melt transesterification are preferred. As mentioned above, polycarbonate resins (A1) and (A2) are preferably manufactured by interfacial polymerization, and polycarbonate resin (A3) is preferably manufactured by interfacial polymerization or melt transesterification in the presence of a branching agent.

[0037] The polycarbonate resin (A) of the present invention can achieve the aforementioned high level of flame retardancy and improve heat retention stability and fluidity by combining a large amount of low molecular weight linear aromatic polycarbonate resin (A1) (30 to 60 parts by mass), a small amount of high molecular weight linear aromatic polycarbonate resin (A2) (10 to 30 parts by mass), and branched aromatic polycarbonate (A3) (20 to 60 parts by mass) based on a total of 100 parts by mass of (A1), (A2), and (A3).

[0038] The preferred amount of polycarbonate resin (A1) is 33 parts by mass or more, more preferably 35 parts by mass or more, among which 38 parts by mass or more, particularly preferably 40 parts by mass or more, preferably 57 parts by mass or less, more preferably 55 parts by mass or less, and even more preferably 53 parts by mass or less. The preferred amount of polycarbonate resin (A2) is 12 parts by mass or more, more preferably 14 parts by mass or more, among which 15 parts by mass or more, 16 parts by mass or more, particularly preferably 17 parts by mass or more, preferably 28 parts by mass or less, and more preferably 27 parts by mass or less, per 100 parts by mass of polycarbonate resin (A). The preferred amount of branched aromatic polycarbonate (A3) is 21 parts by mass or more, more preferably 22 parts by mass or more, even more preferably 23 parts by mass or more, particularly preferably 24 parts by mass or more, preferably 55 parts by mass or less, more preferably 53 parts by mass or less, among which 50 parts by mass or less, 47 parts by mass or less, 45 parts by mass or less, and particularly preferably 43 parts by mass or less. Within this range, it is possible to improve the flame retardancy, anti-dripping properties, and transparency of the resin composition without requiring fluororesin.

[0039] The polycarbonate resins (A1), (A2), and (A3) may be made from virgin raw materials as well as polycarbonate resins recycled from used products (so-called material-recycled polycarbonate resins). It is also preferable to contain both virgin raw materials and recycled resins, and the resin may consist solely of recycled polycarbonate resin. The proportion of recycled polycarbonate resin in polycarbonate resin (A) is preferably 40% or more, 50% or more, 60% or more, or 80% or more, and it is also preferable for recycled polycarbonate resin to be 100%.

[0040] [Organosulfonic acid-based flame retardants that do not contain fluorine atoms (B)] The flame-retardant polycarbonate resin composition of the present invention contains an organic sulfonic acid-based flame retardant (B) that does not contain fluorine atoms.

[0041] As an organic sulfonic acid-based flame retardant that does not contain fluorine atoms, a non-fluorinated organic sulfonic acid or its metal salt that does not have CF bonds in its molecule is preferred. The metal in the metal salt is preferably an alkali metal or an alkaline earth metal, such as alkali metals like lithium (Li), sodium (Na), potassium (K), rubidium (Rb), and cesium (Cs); and alkaline earth metals like magnesium (Mg), calcium (Ca), strontium (Sr), and barium (Ba). Among these, sodium, potassium, and cesium are preferred, with sodium and potassium being particularly preferred.

[0042] Preferred organic sulfonic acids or their metal salts that do not contain fluorine atoms include aromatic sulfonic acids or their metal salts, aromatic sulfonamides (or sulfonimides) or their metal salts, and polystyrene sulfonic acids or their metal salts, with metal salts of these being more preferred.

[0043] Specific examples of these include alkali metal salts of aromatic sulfonic acids having at least one aromatic group in their molecule, such as potassium 3-(phenylsulfonyl)benzenesulfonate (i.e., potassium diphenylsulfon-3-sulfonate), dipotassium diphenylsulfon-3,3'-disulfonate, sodium benzenesulfonate, potassium benzenesulfonate, cesium benzenesulfonate, sodium p-toluenesulfonate, potassium p-toluenesulfonate, cesium p-toluenesulfonate, sodium dodecylbenzenesulfonate, potassium dodecylbenzenesulfonate, cesium dodecylbenzenesulfonate, potassium styrenesulfonate, sodium polystyrenesulfonate, potassium polystyrenesulfonate, and cesium polystyrenesulfonate; Examples include alkaline earth metal salts of aromatic sulfonic acids having at least one aromatic group in their molecule, such as magnesium p-toluenesulfonate, calcium p-toluenesulfonate, strontium p-toluenesulfonate, barium p-toluenesulfonate, magnesium dodecylbenzenesulfonate, and calcium dodecylbenzenesulfonate.

[0044] Examples of metal salts of aromatic sulfonamides (or sulfonimides) include potassium salt of N-(p-tolylsulfonyl)-p-toluenesulfoimide, potassium salt of N-(N'-benzylaminocarbonyl)sulfanilimide, and potassium salt of N-(phenylcarboxyl)-sulfanilimide.

[0045] Among the above, p-toluenesulfonic acid-based flame retardants that do not contain fluorine atoms are preferred, as are p-toluenesulfonic acid or its metal salt, phenylsulfonylbenzenesulfonic acid or its metal salt, and polystyrenesulfonic acid or its metal salt. In particular, these metal salts, especially alkali metal salts, and especially Na salts or K salts are preferred. Organic sulfonic acid-based flame retardants that do not contain fluorine atoms may be used alone, or two or more may be used in any combination and ratio.

[0046] The content of the organic sulfonic acid-based flame retardant (B) that does not contain fluorine atoms is 0.04 to 0.7 parts by mass per 100 parts by mass of polycarbonate resin (A), preferably 0.05 parts by mass or more, more preferably 0.06 parts by mass or more, more preferably 0.07 parts by mass or more, and more preferably 0.60 parts by mass or less, more preferably 0.50 parts by mass or less, 0.40 parts by mass or less, 0.30 parts by mass or less, and particularly preferably 0.25 parts by mass or less. By combining polycarbonate resins (A1), (A2), and (A3) in the predetermined amounts described above with such amounts, a flame-retardant polycarbonate resin composition can be obtained that clears PFAS regulations and achieves V-0 flame retardancy even at a thickness of 1.5 mm with a low amount of additive.

[0047] Furthermore, the flame-retardant polycarbonate resin composition of the present invention does not contain perfluoroalkyl compounds (PFAS), but the fluorine content (amount as F atoms) measured by combustion ion chromatography is preferably less than 100 ppm by mass, more preferably less than 50 ppm by mass, and more particularly less than 30 ppm by mass, less than 20 ppm by mass, less than 10 ppm by mass, less than 5 ppm by mass, less than 3 ppm by mass, less than 2 ppm by mass, less than 1 ppm by mass, and especially 0 ppm by mass.

[0048] [Silicone-based flame retardant additive (C)] The flame-retardant polycarbonate resin composition of the present invention may further preferably contain a silicone-based flame retardant additive (C). As the silicone-based flame retardant additive (C), polyorganosiloxanes are preferred. Among these, polyorganosiloxanes having aromatic groups such as phenyl groups in their molecules are preferred. Examples of such polyorganosiloxanes include polydiphenylsiloxane, polymethylphenylsiloxane, polydimethyldiphenylsiloxane, and phenyl group-containing cyclic siloxanes.

[0049] Furthermore, polyorganosiloxanes may contain functional groups such as silanol groups, epoxy groups, alkoxy groups, hydrosilyl (SiH) groups, and vinyl groups in addition to the organic groups mentioned above. The inclusion of these special functional groups can improve the compatibility between the polyorganosiloxane and polycarbonate resin, and enhance its reactivity during combustion, thereby increasing its flame retardancy. The silanol group content in polyorganosiloxane is typically 1% by mass or more, preferably 2% by mass or more, more preferably 3% by mass or more, and particularly preferably 5% by mass or more, and typically 10% by mass or less, preferably 9% by mass or less, more preferably 8% by mass or less, and particularly preferably 7.5% by mass or less. A high flame retardant effect tends to be obtained by keeping the silanol group content within the above range, and if the silanol group content is too high, the thermal stability and wet heat stability of the polycarbonate resin composition may be significantly reduced.

[0050] Furthermore, polyorganosiloxanes may contain alkoxy groups in addition to hydroxyl groups, but it is preferable that the amount of alkoxy groups be 10% by mass or less. This is because if the amount of alkoxy groups exceeds 10% by mass, gelation is more likely to occur, which may lead to a decrease in the mechanical properties of the polycarbonate resin composition.

[0051] The average molecular weight (weight-average molecular weight, Mw) of polyorganosiloxane can be selected as appropriate, but is usually 350 or higher, preferably 400 or higher, more preferably 450 or higher, and particularly preferably 500 or higher. It is usually 300,000 or lower, preferably 100,000 or lower, more preferably 20,000 or lower, and particularly preferably 15,000 or lower. Polyorganosiloxanes with a weight-average molecular weight below the lower limit of the above range are difficult to manufacture, and the heat resistance of the polyorganosiloxane may also be drastically reduced. Furthermore, polyorganosiloxanes with a weight-average molecular weight exceeding the upper limit of the above range tend to have reduced flame retardancy, possibly due to poor dispersibility, and tend to degrade the mechanical properties of the polycarbonate resin composition. The weight-average molecular weight of polyorganosiloxanes is usually measured by GPC (gel permeation chromatography).

[0052] Furthermore, the silicone-based flame retardant additive (C) is preferably a graft copolymer containing a polyorganosiloxane. It may also be a modified polyorganosiloxane containing the above-mentioned polyorganosiloxane and other (co)polymers, such as butyl polyacrylate or butyl acrylate-styrene copolymer, through graft copolymerization.

[0053] The silicone-based flame retardant additive (C) may be used alone or in a mixture of two or more types.

[0054] The preferred content of the silicone-based flame retardant (C) is 0.1 to 2.0 parts by mass per 100 parts by mass of the polycarbonate resin (A). Within this range, good char formation is observed during combustion, resulting in low heat generation and low smoke emission. The content of the silicone-based flame retardant (C) is more preferably 0.2 parts by mass or more, even more preferably 0.3 parts by mass or more, particularly preferably 0.4 parts by mass or more, and more preferably 1.7 parts by mass or less, even more preferably 1.5 parts by mass or less, particularly preferably 1.3 parts by mass or less.

[0055] [Release agent] The polycarbonate resin composition of the present invention preferably contains 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 preferably 0.1 to 2 parts by mass, more preferably 1 part by mass or less, and even more preferably 0.5 parts by mass or less, per 100 parts by mass of polycarbonate resin (A). If the release agent content is below the lower limit of the above range, the release effect is likely to be insufficient, and if it exceeds the upper limit of the above range, a decrease in hydrolysis resistance and mold contamination during injection molding may occur.

[0065] [Stabilizer] The polycarbonate resin composition of the present invention preferably contains a stabilizer, and phosphorus-based stabilizers or phenol-based stabilizers are preferred.

[0066] Any known phosphorus-based stabilizer can be used. Specific examples include phosphoric acid, phosphonic acid, phosphorous acid, phosphinic acid, polyphosphate and other phosphorus oxoacids; acidic pyrophosphate metal salts such as sodium acidic pyrophosphate, potassium acidic pyrophosphate, and calcium acidic pyrophosphate; phosphates of Group 1 or Group 2 metals such as potassium phosphate, sodium phosphate, cesium phosphate, and zinc phosphate; and organic phosphate compounds, organic phosphite compounds, and organic phosphonite compounds, with organic phosphite compounds being particularly preferred.

[0067] Examples of organic phosphite compounds include triphenyl phosphite, tris(mononylphenyl) phosphite, tris(mononyl / dinonylphenyl) phosphite, tris(2,4-di-tert-butylphenyl) phosphite, monooctyldiphenyl phosphite, dioctylmonophenyl phosphite, monodecyldiphenyl phosphite, didecylmonophenyl phosphite, tridecyl phosphite, trilauryl phosphite, tristearyl phosphite, and 2,2-methylenebis(4,6-di-tert-butylphenyl)octyl phosphite. Examples of such organic phosphite compounds include "ADEKA Stab 1178," "ADEKA Stab 2112," and "ADEKA Stab HP-10" from ADEKA Corporation, "JP-351," "JP-360," and "JP-3CP" from Johoku Chemical Industry Co., Ltd., and "Irgaphos 168" from BASF. Furthermore, the product may contain one type of phosphorus-based stabilizer, or two or more types in any combination and ratio.

[0068] The phosphorus-based stabilizer content is typically 0.001 parts by mass or more, preferably 0.01 parts by mass or more, and more preferably 0.03 parts by mass or more, per 100 parts by mass of polycarbonate resin (A), and typically 1 part by mass or less, preferably 0.7 parts by mass or less, and more preferably 0.5 parts by mass or less. If the phosphorus-based stabilizer content is below the lower limit of the above range, the thermal stabilization effect may be insufficient, and if the phosphorus-based stabilizer content exceeds the upper limit of the above range, the effect may plateau and become uneconomical.

[0069] Examples of phenolic stabilizers include hindered phenolic antioxidants. Specific examples include pentaerythritol tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, thiodiethylenebis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], N,N'-hexane-1,6-diylbis[3-(3,5-di-tert-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-tert-butyl-a,a',a”-(mesitylene-2,4,6- Examples include triyl)tri-p-cresol, 4,6-bis(octylthiomethyl)-o-cresol, ethylenebis(oxyethylene)bis[3-(5-tert-butyl-4-hydroxy-m-tolyl)propionate], hexamethylenebis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], 1,3,5-tris(3,5-di-tert-butyl-4-hydroxybenzyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, 2,6-di-tert-butyl-4-(4,6-bis(octylthio)-1,3,5-triazine-2-ylamino)phenol, and 2-[1-(2-hydroxy-3,5-di-tert-pentylphenyl)ethyl]-4,6-di-tert-pentylphenyl acrylate.

[0070] Among these, pentaerythritol tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] and octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate are preferred. Specific examples of such phenolic antioxidants include BASF's "Irganox 1010" and "Irganox 1076," and ADEKA's "ADEKA Stab AO-50" and "ADEKA Stab AO-60." Furthermore, the product may contain one type of phenolic stabilizer, or two or more types in any combination and ratio.

[0071] The content of the phenolic stabilizer is usually 0.001 parts by mass or more, preferably 0.01 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 polycarbonate resin (A). By setting the content of the phenolic stabilizer to be above the lower limit of the above range, the effect of the phenolic stabilizer can be sufficiently obtained, and by setting it to be below the upper limit of the above range, the effect does not plateau, making it economical.

[0072] [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.

[0073] 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-tert-butyl-phenyl)-benzotriazole, 2-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-3',5'-di-tert-butyl-phenyl)-5-chlorobenzotriazole), and 2-(2'-hydroxy-3',5'-di-ter Examples include t-amyl)-benzotriazole, 2-(2'-hydroxy-5'-tert-octylphenyl)benzotriazole, and 2,2'-methylenebis[4-(1,1,3,3-tetramethylbutyl)-6-(2H-benzotriazole-2-yl)phenol], among which 2-(2'-hydroxy-5'-tert-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'-tert-octylphenyl)benzotriazole is particularly preferred.

[0074] 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.

[0075] Specific examples of salicylate compounds include, for example, phenyl salicylate and 4-tert-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 oxalinide compounds include, for example, 2-ethoxy-2'-ethyloxalinic acid bisalinide. As the malonic acid ester compound, 2-(alkylidene)malonic acid esters are preferred, and 2-(1-arylalkylidene)malonic acid esters are more preferred.

[0076] When an ultraviolet absorber is included, the amount 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 polycarbonate resin (A). If the amount of ultraviolet absorber is below the lower limit of the above range, the effect of improving weather resistance and light resistance may be insufficient, and if the amount of 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.

[0077] [Elastomer] The polycarbonate resin composition of the present invention may also preferably contain an elastomer. As the elastomer, a graft rubber copolymer is preferred, which is obtained by graft copolymerizing a rubber component with a monomer component that can copolymerize with it. The method for producing such a graft rubber copolymer may be any of the following methods: bulk polymerization, solution polymerization, suspension polymerization, emulsion polymerization, etc., and the copolymerization method may be single-stage grafting or multi-stage grafting.

[0078] The above rubber components typically have a glass transition temperature of 0°C or lower, preferably -20°C or lower, and more preferably -30°C or lower. Specific examples of rubber components include polybutadiene rubber, polyisoprene rubber, polyalkyl acrylate rubber such as polybutyl acrylate, poly(2-ethylhexyl acrylate), and butyl acrylate-2-ethylhexyl acrylate copolymer, silicone-based rubber such as organopolysiloxane rubber, butadiene-acrylic composite rubber, IPN-type composite rubber consisting of organopolysiloxane rubber and polyalkyl acrylate rubber, styrene-butadiene rubber, ethylene-α-olefin-based rubber such as ethylene-propylene rubber, ethylene-butene rubber, and ethylene-octene rubber, ethylene-acrylic rubber, and fluororubber. These may be used individually or in mixtures of two or more. Among these, polybutadiene rubber, polyalkyl acrylate rubber, IPN-type composite rubber consisting of organopolysiloxane rubber and polyalkyl acrylate rubber, and styrene-butadiene rubber are preferred in terms of mechanical properties and surface appearance.

[0079] Specific examples of monomer components that can be graft copolymerized with rubber components include aromatic vinyl compounds, vinyl cyanide compounds, (meth)acrylic acid ester compounds, epoxy group-containing (meth)acrylic acid ester compounds such as glycidyl (meth)acrylate; maleimide compounds such as maleimide, N-methylmaleimide, and N-phenylmaleimide; and α,β-unsaturated carboxylic acid compounds such as maleic acid, phthalic acid, and itaconic acid, and their anhydrides (e.g., maleic anhydride). These monomer components may be used individually or in combination of two or more. Among these, aromatic vinyl compounds, vinyl cyanide compounds, (meth)acrylic acid ester compounds, and (meth)acrylic acid compounds are preferred in terms of mechanical properties and surface appearance, 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.

[0080] From the viewpoint of impact resistance and surface appearance, core / shell type graft copolymers are preferred for elastomers. Among these, core / shell type graft copolymers are preferred, which consist of a core layer made of at least one rubber component selected from polybutadiene-containing rubber, polybutyl acrylate-containing rubber, and IPN-type composite rubber consisting of organopolysiloxane rubber and polyalkyl acrylate rubber, and a shell layer formed by copolymerizing (meth)acrylic acid ester around it, with core / shell type elastomers using butadiene-based rubber as the core being particularly preferred. In the above core / shell type graft copolymer, it is preferable that the rubber component is contained in 40% by mass or more, and more preferably 60% by mass or more. Furthermore, it is preferable that the (meth)acrylic acid component is contained in 10% by mass or more.

[0081] Preferred specific examples of these 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 IPN rubber) copolymer. Such rubbery polymers may be used individually or in combination of two or more types.

[0082] When the polycarbonate resin composition of the present invention contains an elastomer (D), it is preferable that the elastomer (D) is contained in an amount of 0.01 to 10 parts by mass, particularly 1 to 10 parts by mass, and especially 2 to 8 parts by mass, per 100 parts by mass of polycarbonate resin (A).

[0083] [Additives, etc.] The polycarbonate resin composition of the present invention may contain other additives besides those mentioned above, such as fillers, fluorescent whitening agents, pigments, dyes, plasticizers, and compatibilizers. These additives may be present in one or more types.

[0084] Furthermore, other resins besides polycarbonate resin (A) may be included. Examples of other resins include thermoplastic polyester resins such as polyethylene terephthalate, polytrimethylene terephthalate, and polybutylene terephthalate; styrene-based resins such as polystyrene resin, high-impact polystyrene resin (HIPS), acrylonitrile-butadiene-styrene copolymer (ABS resin), 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. If other resins are included besides polycarbonate resin (A), the content 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, among which 3 parts by mass or less, 2 parts by mass or less, and especially preferably 1 part by mass or less.

[0085] [Flame-retardant polycarbonate resin composition] The flame-retardant polycarbonate resin composition of the present invention has high flame retardancy and can achieve V-0 in UL-94 testing with a UL test specimen 1.5 mm thick.

[0086] The flame-retardant polycarbonate resin composition of the present invention is molded into a molded article. The manufacturing method for the molded product can be any molding method commonly used for polycarbonate resin compositions. Examples include injection molding, ultra-high-speed injection molding, injection compression molding, two-color molding, hollow molding methods such as gas-assisted molding, molding using insulated molds, molding using rapidly heated molds, foam molding (including supercritical fluids), insert molding, IMC (in-mold coating) molding, extrusion molding, sheet molding, thermoforming, rotational molding, lamination molding, press molding, and blow molding. Molding methods using a hot runner system can also be used. Among these, injection molding methods such as injection molding, ultra-high-speed injection molding, and injection compression molding are preferred.

[0087] [Molded products] Examples of molded products include parts for electrical and electronic equipment, office automation equipment, information terminal equipment, machine parts, home appliances, vehicle parts, building materials, various containers, leisure goods and miscellaneous items, and lighting equipment. In particular, it is suitable for use in parts for electrical and electronic equipment, office automation equipment, information terminal equipment, home appliances, and lighting equipment. For example, it is suitable for use in components for secondary battery devices used indoors or outdoors, battery packs, storage batteries for electric bicycles, and components for enclosures used outdoors. [Examples]

[0088] The present invention will be described in more detail below with reference to examples. However, the present invention is not limited to the following examples. The components used in the examples and comparative examples are shown in Table 1 below.

[0089] [Table 1]

[0090] (Examples 1-6, Comparative Examples 1-5) <Method for producing resin composition pellets> Each of the above-mentioned components was blended in the proportions (parts by mass) shown in Table 2 below, mixed in a tumbler for 20 minutes, and then supplied to a twin-screw extruder "TEX30α" manufactured by Japan Steel Works, Ltd. equipped with one vent. The mixture was kneaded under the conditions of a screw rotation speed of 200 rpm, a discharge rate of 30 kg / hr, and a barrel temperature of 310°C. The molten resin extruded in strand form was rapidly cooled in a water bath and pelletized using a pelletizer to obtain resin composition pellets.

[0091] <Flow Value (Q Value)> The flow value (Q value) of the resin composition pellets obtained above was measured according to the method described in Annex C of JIS K7210. The measurement was performed using a Shimadzu Corporation "Flow Tester CFT-500EX" with a die of 1.0 mm in diameter and 10 mm in length, at a test temperature of 277°C and a test force of 160 kg / cm². 2 The amount of molten resin discharged under the condition of a preheating time of 420 seconds (unit: cm) 3 The measurement (per second) was taken.

[0092] <Flame retardancy rating: UL-94> The resin composition pellets obtained by the above manufacturing method were dried at 120°C for 4 hours, and then injection molded using a Sumitomo Heavy Industries SE100DU injection molding machine under the conditions of cylinder temperature 300°C, mold temperature 80°C, and molding cycle of 40 seconds to obtain UL-94 test pieces with a length of 125 mm, a width of 13 mm, and a thickness of 1.5 mm. The UL-94 test specimens (1.5 mm thick) obtained above were tested in accordance with the UL-94 test (flammability test for plastic materials for equipment components) established by Underwriters Laboratories (UL) in the United States. The flammability results were classified as V-0, V-1, V-2, and HB from best to worst, with those that did not meet the specifications being classified as NG.

[0093] <Measurement of fluorine content (unit: mass ppm)> The fluorine content in the resin composition was quantified by combustion ion chromatography. Specifically, the polycarbonate resin composition pellets obtained above were heated in an argon atmosphere at 270°C for 10 minutes using an automated sample combustion device, the "AQF-100" manufactured by Mitsubishi Chemical Analytec Co., Ltd., and the amount of fluorine ions generated was quantified using the "ICS-90" manufactured by Nippon Dionex Co., Ltd. To calculate the content, a calibration curve created from separately prepared standard substances was used. Substances that were difficult to measure due to being below the detection limit of 5 ppm during analysis by combustion ion chromatography are marked "ND" (not detected) in Table 2. Resin compositions that do not contain PFAS compounds are naturally marked as ND.

[0094] The evaluation results are shown in Table 2 below.

[0095] [Table 2] [Industrial applicability]

[0096] The flame-retardant polycarbonate resin composition of the present invention complies with PFAS regulations and is an environmentally friendly material, while possessing high flame retardancy, excellent heat retention stability, and superior resistance to humid heat. Therefore, it can be suitably used in various molded products.

Claims

1. A flame-retardant polycarbonate resin composition characterized by containing 0.04 to 0.7 parts by mass of an organic sulfonic acid-based flame retardant (B) that does not contain fluorine atoms, per 100 parts by mass of polycarbonate resin (A), which contains 30 to 60 parts by mass of a linear aromatic polycarbonate resin (A1) with a viscosity-average molecular weight of 10,000 to 25,000, 10 to 30 parts by mass of a linear aromatic polycarbonate resin (A2) with a viscosity-average molecular weight of 50,000 to 90,000, and 20 to 60 parts by mass of a branched aromatic polycarbonate (A3) with a viscosity-average molecular weight of 25,000 to 40,000.

2. The polycarbonate resin composition according to claim 1, which does not contain perfluoroalkyl compounds (PFAS) and has a fluorine content of less than 100 ppm by mass as measured by combustion ion chromatography.

3. The polycarbonate resin composition according to claim 1 or 2, wherein the resin composition does not contain fluorine atoms.

4. The polycarbonate resin composition according to claim 1 or 2, wherein the organic sulfonic acid-based flame retardant (B) that does not contain a fluorine atom is one or more of the following: p-toluenesulfonic acid or its metal salt, or phenylsulfonylbenzenesulfonic acid or its metal salt.

5. Furthermore, the polycarbonate resin composition according to claim 1 or 2, further comprising 0.1 to 2.0 parts by mass of a silicone-based flame retardant additive (C) per 100 parts by mass of polycarbonate resin (A).

6. The polycarbonate resin composition according to claim 1 or 2, wherein the UL-94 rating at a thickness of 1.5 mm is V-0.

7. Pellets of the polycarbonate resin composition according to claim 1 or 2.

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

9. A molded article of pellets according to claim 7.

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