Flame-retardant polycarbonate resin composition

Abstract

To provide a polycarbonate resin composition that generates no toxic gas during combustion, clears regulations for PFAS and the like, has advanced flame retardancy with environmental consideration, and also has excellent heat resistance.SOLUTION: A flame-retardant polycarbonate resin composition characterized by comprising, per 100 pts.mass of a polycarbonate resin (A), 0.5-8 pts.mass of expandable graphite (B) and 3-15 pts.mass of a silicone-based flame retardant (C).SELECTED DRAWING: None

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 meets PFAS regulations, is an environmentally friendly material, and yet has high flame retardancy and excellent heat resistance. [Background technology]

[0002] Polycarbonate resins are resins with excellent heat resistance, mechanical properties, and electrical characteristics, and are widely used, for example, as materials for manufacturing vehicle parts, electrical and electronic equipment parts, housing materials, and other industrial parts. In particular, flame-retardant polycarbonate resin compositions are suitably used as vehicle parts, electrical and electronic equipment parts such as personal computers, mobile phones, and battery cases, and parts for office automation and information equipment such as printers and copiers.

[0003] In recent years, there has been an increasing trend towards flame retardancy, and polycarbonate resins are now required to have a high level of flame retardancy, with many cases requiring V-0 products under the UL-94 test method. Halogen-based flame retardants and phosphorus-based flame retardants have been used to impart flame retardancy to polycarbonate resins. However, in order to achieve V-0 flame retardancy using phosphorus-based flame retardants, a relatively high addition rate is required, which tends to reduce the mechanical properties of polycarbonate resin materials. Flame retardancy using halogen-based bromine-based or chlorine-based flame retardants is being banned under stricter regulations due to the toxicity and environmental issues caused by the emission of harmful gases.

[0004] In particular, fluorine-based flame retardants, such as perfluoroalkane metal salts proposed in Patent Documents 1 and 2, can provide a high level of flame retardancy with a relatively small amount of compounding. Furthermore, by blending such a flame retardant together with polyfluoroethylene as an anti-dripping agent, dripping can be suppressed and flame retardancy can be further improved. However, in recent years, fluorine compounds have become subject to international regulations, led by Japan, Europe, and the United States, and PFAS restrictions on perfluoroalkyl and polyfluoroalkyl compounds are being implemented primarily in the EU and the United States, and polyfluoroethylene and other compounds are also being targeted. PFAS restrictions are becoming even stricter internationally. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Special Publication No. 47-40445 [Patent Document 1] Japanese Unexamined Patent Publication No. 49-88943 Summary of the Invention [Problem to be solved by the invention]

[0006] Therefore, there is a strong demand for a highly functional, environmentally friendly flame-retardant polycarbonate resin composition that does not emit toxic gases during combustion, meets various regulations such as PFAS regulations, etc. However, it is not easy to achieve a V-0 rating in the UL-94 test without using a non-halogen flame retardant or a non-phosphorus flame retardant, or without using polytetrafluoroethylene as a drip prevention agent. The present invention has been made in view of the above circumstances, and an object (object) of the present invention is to provide a polycarbonate resin composition that complies with regulations on PFAS and the like, and exhibits a high level of flame retardancy that is environmentally friendly. [Means for solving the problem]

[0007] As a result of extensive research into achieving the above object, the present inventors have found that the above object can be achieved by including expandable graphite and a silicone-based flame retardant, and have thus completed the present invention. The present invention relates to the following polycarbonate resin composition and molded article.

[0008] 1. A flame-retardant polycarbonate resin composition comprising 100 parts by mass of polycarbonate resin (A), 0.5 to 8 parts by mass of expandable graphite (B), and 3 to 15 parts by mass of a silicone-based flame retardant (C). 2. The resin composition according to the above item 1, wherein the mass ratio of the contents of the expandable graphite (B) and the silicone-based flame retardant (C) is 0.01 to 0.50. 3. The resin composition according to 1 or 2 above, wherein the silicone flame retardant (C) has a melting point of 50°C or higher. 4. The resin composition according to any one of the above 1 to 3, further comprising 1 to 90 parts by mass of a filler (D) per 100 parts by mass of the polycarbonate resin (A). 5. The resin composition according to any one of the above 1 to 4, wherein the filler (D) is glass fiber. 6. The resin composition according to any one of the above 1 to 5, further comprising a release agent (E) in an amount of 0.1 to 2 parts by mass per 100 parts by mass of the polycarbonate resin (A). 7. The resin composition according to any one of 1 to 6 above, wherein the UL-94 of a 1.5 mm thickness is V-0. 8. The resin composition according to any one of 1 to 7 above, which has a deflection temperature under load measured according to ISO 75 A method of more than 130°C. 9. Pellets of the resin composition according to any one of 1 to 8 above. 10. A molded article made from the resin composition according to any one of 1 to 8 above. 11. A molded product of the pellets described in 9 above. [Effects of the Invention]

[0009] The flame-retardant polycarbonate resin composition of the present invention does not emit toxic gases when burned, meets regulations such as PFAS, and has environmentally friendly high-level flame retardancy and excellent heat resistance. DETAILED DESCRIPTION OF THE INVENTION

[0010] The present invention will be described in detail below with reference to embodiments and examples. In this specification, unless otherwise specified, the symbol "to" is used to mean that the numerical values ​​before and after it are included as the lower limit and upper limit.

[0011] The polycarbonate resin composition of the present invention is characterized by containing 0.5 to 8 parts by mass of expandable graphite (B) and 3 to 15 parts by mass of a silicone flame retardant (C) relative to 100 parts by mass of a polycarbonate resin (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 carbons directly bonded to the carbonate bonds are aromatic carbons, and aliphatic polycarbonate resins in which the carbons directly bonded to the carbonate bonds are aliphatic carbons, and either type can be used. Among these, aromatic polycarbonate resins are preferred as the polycarbonate resin (A) from the viewpoints of heat resistance, mechanical properties, electrical properties, etc.

[0013] Among the monomers that are raw materials for aromatic polycarbonate resins, examples of aromatic dihydroxy compounds 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] dihydroxynaphthalenes 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-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;

[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-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;

[0018] 9,9-bis(4-hydroxyphenyl)fluorene, Cardo structure-containing bisphenols 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'-dihydroxydiphenyl sulfone, dihydroxydiarylsulfones such as 4,4'-dihydroxy-3,3'-dimethyldiphenylsulfone; etc.

[0020] Of these, bis(hydroxyaryl)alkanes are preferred, and bis(4-hydroxyphenyl)alkanes are particularly preferred. In particular, from the standpoints of impact resistance and heat resistance, 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. The aromatic dihydroxy compounds may be used alone or in any combination of two or more in any ratio.

[0021] Among the monomers that serve as raw materials for polycarbonate resins, examples of carbonate precursors include carbonyl halides, carbonate esters, etc. The carbonate precursors may be used alone or in any combination and ratio of two or more.

[0022] Specific examples of carbonyl halides include phosgene; haloformates such as bischloroformates of dihydroxy compounds and monochloroformates of dihydroxy compounds; and the like.

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

[0024] The method for producing the polycarbonate resin (A) is not particularly limited, and any method can be used. Examples include interfacial polymerization, melt transesterification, ring-opening polymerization of a cyclic carbonate compound, and solid-phase transesterification of a prepolymer. Among these, the interfacial polymerization and melt transesterification methods are preferred because they have a greater effect of improving moist heat resistance, and the interfacial polymerization method is particularly preferred.

[0025] The molecular weight of the polycarbonate resin (A), expressed as a viscosity average molecular weight (Mv) calculated from the solution viscosity measured at 25°C using methylene chloride as a solvent, is preferably 10,000 to 50,000, more preferably 11,000 to 40,000, even more preferably 12,000 to 35,000, and particularly preferably 13,000 to 30,000. By setting the viscosity average molecular weight to at least 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 at most the upper limit of the above range, the decrease in flowability of the polycarbonate resin composition of the present invention can be suppressed and improved, and molding processability can be improved, making molding process easier. Two or more polycarbonate resins having different viscosity average molecular weights may be mixed together, and in this case, polycarbonate resins having viscosity average molecular weights outside the above-mentioned preferred range may be mixed.

[0026] The viscosity average molecular weight [Mv] is calculated by using methylene chloride as a solvent and an Ubbelohde viscometer to determine the intrinsic viscosity [η] (unit: dl / g) at a temperature of 25°C, and then calculating it using the Schnell viscosity formula, i.e., η = 1.23 × 10 -4 Mv 0.83 The intrinsic viscosity [η] is the specific viscosity [η] at each solution concentration [C] (g / dl). sp ] was measured and the value was calculated according to the following formula.

number

[0027] Furthermore, in order to improve the appearance and fluidity of molded articles, the polycarbonate resin (A) may contain a polycarbonate oligomer. The viscosity average molecular weight [Mv] of this polycarbonate oligomer is usually 1500 or more, preferably 2000 or more, and usually 9500 or less, preferably 9000 or less. Furthermore, the amount of the polycarbonate oligomer contained is preferably 30% by mass or less of the polycarbonate resin (including the polycarbonate oligomer).

[0028] Furthermore, the polycarbonate resin (A) may be not only virgin raw materials but also polycarbonate resin recycled from used products (so-called material-recycled polycarbonate resin), and it is also preferable to contain both virgin polycarbonate resin and recycled polycarbonate resin, or it may consist of recycled polycarbonate resin. When recycled polycarbonate resin is contained, the proportion of recycled polycarbonate resin in polycarbonate resin (A) is preferably 30% or more, 40% or more, 50% or more, 60% or more, or 80% or more, and it is also preferable that the recycled polycarbonate resin is 100%.

[0029] [Expandable graphite (B)] Expandable graphite (B) is a layered material obtained by treating graphite powder with an inorganic acid and a strong oxidizing agent, for example, to intercalate an intercalant such as the acid between graphite layers. Examples of graphite include natural flaky graphite and pyrolytic graphite. Examples of inorganic acids include concentrated sulfuric acid, nitric acid, and selenic acid. Examples of strong oxidizing agents include concentrated nitric acid, perchloric acid, perchlorates, permanganates, dichromates, and hydrogen peroxide. The expandable graphite obtained by the above treatment may be further neutralized with ammonia, aliphatic lower amines, alkali metal compounds, alkaline earth metal compounds, and the like. When expandable graphite is exposed to high heat, the intercalant present between layers is converted from a liquid or solid phase to a gas phase, causing an expansion action, and the graphite has the property of rapidly expanding when exposed to high heat such as a flame. For this reason, it is thought that when exposed to high heat such as a flame, the vaporized intercalant increases the flame retardancy of the polycarbonate resin composition and also expands the polycarbonate resin composition, further improving the flame retardancy due to the heat insulating effect. Expandable graphite (B) is commercially available, and commercially available expandable graphite can be used. Examples of commercially available expandable graphite include "EXP-50S300", "EXP-100S", "EXP-50S120K", "EXP-50S120N", "EXP-50S150", "EXP-50KK", "EXP-50HO", "EXP-80S220", "EXP-50SL", "EXP-150S", "EXP-200S", "EXP-50S", "EXP-80S", "EXP-100S", "EXP-32S160", and "EXP-50S160" manufactured by Fuji Graphite Industries Co., Ltd., and "9550250", "9532400A", "953240L", and "99 Examples include "50200", "955025L", "9280170", and "9510045" from Suzuhiro Chemical Co., Ltd., "GREP-EG" from Air Water Performance Chemicals Inc., "CA-60", "MZ-260", "SS-3LA", "SS-3", and "SS-3N" from Air Water Performance Chemicals Inc., and "GG250-50N", "GG160-50N", "GG160-80N", "GG180-60N", "GG200-100N", "GG210-200N", "GG220-50N", "GG220-80B", "GG225-270N", and "GG280-50N" from NeoGraf.

[0030] The content of expandable graphite (B) is 0.5 to 8 parts by mass per 100 parts by mass of polycarbonate resin (A), and by setting the content in this range, good flame retardancy is achieved. If the content is less than the above lower limit, the flame retardancy is insufficient, and even if the content is increased beyond the upper limit, the flame retardancy is unlikely to be good. Furthermore, when the polycarbonate resin composition is produced by melt-kneading, the polycarbonate decomposes, reducing the melt viscosity, making pelletization difficult. The content of the expandable graphite (B) is preferably 0.6 parts by mass or more, more preferably 0.7 parts by mass or more, and is preferably 7 parts by mass or less, more preferably 6.5 parts by mass or less, even more preferably 6.0 parts by mass or less, 5.5 parts by mass or less, and particularly preferably 5.0 parts by mass or less, per 100 parts by mass of the polycarbonate resin (A).

[0031] [Silicone flame retardants (C)] The polycarbonate resin composition of the present invention contains a silicone-based flame retardant (C). As the silicone flame retardant (C), polyorganosiloxane is preferred. Among them, polyorganosiloxane having an aromatic group such as a phenyl group in the molecule is preferred. Examples of such polyorganosiloxane include polydiphenylsiloxane, polymethylphenylsiloxane, polydimethyldiphenylsiloxane, and phenyl-containing cyclic siloxane.

[0032] Furthermore, in addition to the organic groups described above, polyorganosiloxane may contain functional groups such as silanol groups, epoxy groups, alkoxy groups, hydrosilyl (SiH) groups, vinyl groups, etc. The inclusion of these special functional groups may improve the compatibility of polyorganosiloxane with polycarbonate resins and improve reactivity during combustion, thereby increasing flame retardancy.

[0033] The silanol group content in the polyorganosiloxane is usually 1 mass% or more, preferably 2 mass% or more, more preferably 3 mass% or more, and particularly preferably 5 mass% or more, and is usually 10 mass% or less, preferably 9 mass% or less, more preferably 8 mass% or less, and particularly preferably 7.5 mass% or less. By setting the silanol group content within the above range, a high flame retardant effect tends to be obtained, and if the silanol group content is too high, the thermal stability of the polycarbonate resin composition may be significantly reduced.

[0034] The polyorganosiloxane may contain alkoxy groups in addition to hydroxyl groups, but the amount thereof is preferably 10% by mass or less, because if the alkoxy group content exceeds 10% by mass, gelation is likely to occur, which may lead to a decrease in the mechanical properties of the polycarbonate resin composition.

[0035] The silicone flame retardant (C) is also preferably a graft copolymer containing polyorganosiloxane. It may be a modified polyorganosiloxane containing the above-mentioned polyorganosiloxane and another (co)polymer, such as polybutyl acrylate or butyl acrylate-styrene copolymer, graft copolymerized therewith.

[0036] The silicone flame retardant (C) may be used alone or in combination of two or more.

[0037] The silicone flame retardant (C) may be in any form, such as solid or liquid, but a melting point of 50°C or higher is preferred in order to form a strong foamed char when used in combination with the intumescent black smoke. The melting point is more preferably 60°C or higher, and even more preferably 70°C or higher.

[0038] The content of the silicone flame retardant (C) is 3 to 15 parts by mass per 100 parts by mass of the polycarbonate resin (A). Combining this amount with the expandable graphite (B) results in good foamed char formation upon combustion, resulting in high flame retardancy. The content of the silicone flame retardant (C) is preferably 3.5 parts by mass or more, with 4 parts by mass or more being particularly preferred, and is preferably 13 parts by mass or less, with 11 parts by mass or less, 9 parts by mass or less, and particularly 8 parts by mass or less being particularly preferred.

[0039] In the present invention, the mass ratio (B / C) of the contents of the expandable graphite (B) and the silicone-based flame retardant (C) is preferably 0.01 to 0.50. By setting the mass ratio (B / C) of the contents of the two in this manner, a synergistic effect of the flame retardancy provided by the expandable graphite (B) and the flame retardancy provided by the silicone-based flame retardant (C) is achieved, which is preferable, and the mass ratio (B / C) of the contents is more preferably 0.05 or more, particularly preferably 0.08 or more, 0.10 or more, 0.12 or more, 0.13 or more, and particularly preferably 0.15 or more, and is more preferably 0.45 or less, particularly preferably 0.40 or less.

[0040] The polycarbonate resin composition of the present invention preferably contains substantially no phosphorus-based flame retardants or halogen-based flame retardants. Here, "substantially no" means that the amount of the phosphorus-based flame retardants and / or halogen-based flame retardants, individually or in total, per 100 parts by mass of the polycarbonate resin (A), is preferably less than 0.05 parts by mass, more preferably less than 0.03 parts by mass, even more preferably less than 0.01 parts by mass, less than 0.005 parts by mass, less than 0.001 parts by mass, particularly preferably less than 0.0005 parts by mass.

[0041] [Filling material (D)] The polycarbonate resin composition of the present invention preferably contains a filler (D). By containing the filler (D) in combination with the expandable graphite (B) and the silicone-based flame retardant (C), the flame retardancy of the expandable graphite (B) and the silicone-based flame retardant (C) and the dripping prevention ability of the filler (D) can be balanced to further improve the flame retardancy. The content of the filler (D) is preferably 1 to 90 parts by mass, more preferably 3 parts by mass or more, even more preferably 5 parts by mass or more, 7 parts by mass or more, or 10 parts by mass or more, per 100 parts by mass of the polycarbonate resin (A), and more preferably 80 parts by mass or less, even more preferably 75 parts by mass or less, or particularly preferably 70 parts by mass or less. The filler (D) may be contained in one kind or in two or more kinds.

[0042] The filler (D) is preferably an inorganic filler, and the inorganic filler may be any of an acicular inorganic filler, a fibrous inorganic filler, and a plate-like inorganic filler. An acicular inorganic filler is an inorganic filler having a whisker-like or columnar shape, such as wollastonite. A fibrous inorganic filler refers to a thin and long fibrous inorganic filler, such as glass fiber, ceramic fiber, or carbon fiber. Examples of the shape of the fibrous inorganic filler include chopped strands and milled fibers. A plate-like inorganic filler is an inorganic filler having a flake-like or scaly shape, such as talc, mica, or glass flakes.

[0043] The filler (D) is preferably a glass-based filler, and preferred examples thereof include glass fiber, glass flake, glass beads, and glass balloons, with glass fiber and glass flake being particularly preferred. The raw glass composition is preferably alkali-free, and examples thereof include E glass, C glass, S glass, and R glass, with E glass being preferred.

[0044] The cross-sectional shape of the glass fiber may be a typical perfect circle or various irregular cross-sectional shapes. The number average fiber length (cut length) of the glass fiber is preferably 0.5 to 10 mm, more preferably 1.0 to 5.0 mm. The number average fiber diameter of the glass fiber is preferably 4.0 μm or more, more preferably 4.5 μm or more, and even more preferably 5.0 μm or more, with the upper limit being preferably 25.0 μm or less, more preferably 20 μm or less. Glass fibers having a flat cross section are also preferred, with an aspect ratio of 1.5 to 8 being more preferred, and an aspect ratio of 2 to 6 being even more preferred. The glass flakes are, for example, scale-like flakes having a thickness of 1 to 20 μm and a side length of 0.05 to 1.0 mm.

[0045] The glass-based filler is also preferably surface-treated with a surface treatment agent such as a silane coupling agent, for example, γ-methacryloxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, or γ-aminopropyltriethoxysilane. The amount of the surface treatment agent attached is preferably 0.01 to 1% by mass of the glass-based filler. Furthermore, if necessary, the glass-based filler may be surface-treated with a lubricant such as a fatty acid amide compound or silicone oil, an antistatic agent such as a quaternary ammonium salt, a film-forming resin such as an epoxy resin or urethane resin, or a mixture of a film-forming resin with a heat stabilizer, a flame retardant, or the like.

[0046] [Release agent] The resin composition of the present invention preferably contains a mold release agent. Examples of the release agent include aliphatic carboxylic acids, esters of aliphatic carboxylic acids and alcohols, aliphatic hydrocarbon compounds having a number average molecular weight of 200 to 15,000, and polysiloxane-based silicone oils.

[0047] Examples of aliphatic carboxylic acids include saturated or unsaturated aliphatic mono-, di-, or tri-carboxylic acids. Aliphatic carboxylic acids also include alicyclic carboxylic acids. Among these, preferred aliphatic carboxylic acids are mono- or di-carboxylic acids having 6 to 36 carbon atoms, with saturated aliphatic mono-carboxylic acids having 6 to 36 carbon atoms being more preferred. Specific examples of such aliphatic carboxylic acids include palmitic acid, stearic acid, caproic acid, capric acid, lauric acid, arachic acid, behenic acid, lignoceric acid, cerotic acid, melissic acid, tetralinic acid, montanic acid, adipic acid, and azelaic acid.

[0048] The aliphatic carboxylic acid in the ester of an aliphatic carboxylic acid and an alcohol can be, for example, the same as the aliphatic carboxylic acid described above. On the other hand, the alcohol can be, for example, a saturated or unsaturated monohydric or polyhydric alcohol. These alcohols may have a substituent such as a fluorine atom or an aryl group. Among these, a monohydric or polyhydric saturated alcohol having 30 or less carbon atoms is preferred, and an aliphatic saturated monohydric alcohol or an aliphatic saturated polyhydric alcohol having 30 or less carbon atoms is more preferred. Here, the term "aliphatic" is used to include alicyclic compounds.

[0049] 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.

[0050] The ester may contain an aliphatic carboxylic acid and / or an alcohol as an impurity. The ester may be a pure substance or a mixture of multiple compounds. The aliphatic carboxylic acid and the alcohol that combine to form an ester may each be used alone or in any combination and ratio of two or more.

[0051] Specific examples of esters of aliphatic carboxylic acids and alcohols include beeswax (a mixture containing myricyl palmitate as a main component), 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.

[0052] Examples of aliphatic hydrocarbons having a number average molecular weight of 200 to 15,000 include liquid paraffin, paraffin wax, microcrystalline wax, polyethylene wax, Fischer-Tropsch wax, and α-olefin oligomers having 3 to 12 carbon atoms. Aliphatic hydrocarbons also include alicyclic hydrocarbons. These hydrocarbons may be partially oxidized. Among these, paraffin wax, polyethylene wax, or a partial oxide of polyethylene wax is preferred, and paraffin wax and polyethylene wax are more preferred. The number average molecular weight of the aliphatic hydrocarbon is preferably 5,000 or less. The aliphatic hydrocarbon may be a single substance, but a mixture of substances with various constituent components and molecular weights can also be used as long as the main component is within the above range.

[0053] Examples of polysiloxane-based silicone oils include dimethyl silicone oil, methylphenyl silicone oil, diphenyl silicone oil, and fluorinated alkyl silicone.

[0054] The above-mentioned release agents may be contained either alone or in any combination and ratio of two or more.

[0055] The content of the release agent 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, relative to 100 parts by mass of the polycarbonate resin (A). If the content of the release agent is less than the lower limit of the above range, the release effect tends to be insufficient, whereas if it exceeds the upper limit of the above range, the hydrolysis resistance may decrease and mold contamination during injection molding may occur.

[0056] [Stabilizer] The polycarbonate resin composition of the present invention preferably contains a stabilizer, and the stabilizer is preferably a phosphorus-based stabilizer or a phenol-based stabilizer.

[0057] Any known phosphorus stabilizer can be used. Specific examples include phosphorus oxoacids such as phosphoric acid, phosphonic acid, phosphorous acid, phosphinic acid, and polyphosphoric acid; metal acid pyrophosphates such as sodium acid pyrophosphate, potassium acid pyrophosphate, and calcium acid pyrophosphate; phosphates of Group 1 or Group 2 metals such as potassium phosphate, sodium phosphate, cesium phosphate, and zinc phosphate; organic phosphate compounds, organic phosphite compounds, and organic phosphonite compounds, with organic phosphite compounds being particularly preferred.

[0058] 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 "ADK STAB 1178," "ADK STAB 2112," and "ADK STAB HP-10" manufactured by ADEKA CORPORATION, "JP-351," "JP-360," and "JP-3CP" manufactured by Johoku Chemical Industry Co., Ltd., and "IRGAFOS 168" manufactured by BASF. The phosphorus-based stabilizer may be contained either as one type or as two or more types in any combination and ratio.

[0059] The content of the phosphorus-based stabilizer is usually 0.001 part by mass or more, preferably 0.01 part by mass or more, more preferably 0.03 part by mass or more, and usually 1 part by mass or less, preferably 0.7 part by mass or less, more preferably 0.5 part by mass or less, relative to 100 parts by mass of the polycarbonate resin (A). If the content of the phosphorus-based stabilizer is below the lower limit of the above range, the thermal stabilization effect may be insufficient, whereas if the content of the phosphorus-based stabilizer exceeds the upper limit of the above range, the effect may plateau and become uneconomical.

[0060] Examples of the phenolic stabilizer include hindered phenolic antioxidants. Specific examples thereof 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]phosphate, 3,3',3",5,5',5"-hexa-tert-butyl-a,a',a"-(mesitylene-2,4,6- triyl)tri-p-cresol, 4,6-bis(octylthiomethyl)-o-cresol, ethylene bis(oxyethylene) bis[3-(5-tert-butyl-4-hydroxy-m-tolyl)propionate], hexamethylene bis[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-triazin-2-ylamino)phenol, 2-[1-(2-hydroxy-3,5-di-tert-pentylphenyl)ethyl]-4,6-di-tert-pentylphenyl acrylate, and the like.

[0061] 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 "Irganox 1010" and "Irganox 1076" manufactured by BASF, and "Adekastab AO-50" and "Adekastab AO-60" manufactured by ADEKA. The phenolic stabilizer may be contained in one kind or in any combination and ratio of two or more kinds.

[0062] The content of the phenolic stabilizer is usually 0.001 part by mass or more, preferably 0.01 part by mass or more, and usually 1 part by mass or less, preferably 0.5 parts by mass or less, relative to 100 parts by mass of the polycarbonate resin (A). By setting the content of the phenolic stabilizer to be equal to or more than the lower limit of the above range, the effect as a phenolic stabilizer can be sufficiently obtained, and by setting the content to be equal to or less than the upper limit of the above range, the effect does not plateau and is economical.

[0063] [Additives, etc.] The polycarbonate resin composition of the present invention may contain additives other than those described above, such as ultraviolet absorbers, fluorescent brighteners, pigments, dyes, plasticizers, compatibilizers, etc. These additives may be contained alone or in combination of two or more.

[0064] Furthermore, the polycarbonate resin (A) may contain other resins. 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-styrene copolymer (AS resin), and acrylonitrile-butadiene-styrene copolymer (ABS 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 a resin other than the polycarbonate resin (A) is contained, the content thereof is preferably 45 parts by mass or less per 100 parts by mass of the polycarbonate resin (A), and particularly preferably 40 parts by mass or less, 30 parts by mass or less, 20 parts by mass or less, 10 parts by mass or less, 5 parts by mass or less, 3 parts by mass or less, 2 parts by mass or less, and particularly preferably 1 part by mass or less.

[0065] [Polycarbonate resin composition] The polycarbonate resin composition of the present invention has a high level of flame retardancy, and can achieve V-0 in a UL-94 test using a 1.5 mm thick UL test piece. Furthermore, the polycarbonate resin composition of the present invention has excellent heat resistance, and the deflection temperature under load measured in accordance with ISO 75 A method is preferably higher than 130°C, more preferably 131°C, 132°C or higher, 133°C or higher, 134°C or higher, and even more preferably 135°C or higher.

[0066] The polycarbonate resin composition of the present invention can be molded into a molded article. The molding method for producing a molded article 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, gas-assisted hollow molding, molding using an insulated mold, molding using a rapidly heated mold, foam molding (including supercritical fluid), insert molding, IMC (in-mold coating molding), extrusion molding, sheet molding, thermoforming, rotational molding, laminate 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.

[0067] [Molded products] Examples of molded articles 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 goods, lighting equipment, etc. Among these, the molded articles are suitable for use in parts for electrical and electronic equipment, office automation equipment, information terminal equipment, home appliances, lighting equipment, etc., and are suitable for use in, for example, components for secondary battery devices used indoors or outdoors, battery packs, storage batteries for electric bicycles, etc., and components for housings used outdoors. [Example]

[0068] Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not construed as being limited to the following examples. The components used in the examples and comparative examples are as shown in Table 1 below.

[0069] [Table 1]

[0070] (Examples 1 to 4, Comparative Examples 1 to 5) <Manufacture of Resin Composition Pellets> The above components were 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 1 vent. Kneading was carried out under the conditions of a screw rotation speed of 200 rpm, a discharge rate of 25 kg / hr, and a barrel temperature of 280°C. The molten resin extruded in a strand shape was rapidly cooled in a water tank and pelletized using a pelletizer to obtain pellets of the polycarbonate resin composition.

[0071] <Production of Test Specimens for UL-94> After drying the resin composition pellets obtained by the above production method at 120°C for 4 hours, injection molding was carried out using a SE100DU type injection molding machine manufactured by Sumitomo Heavy Industries, Ltd. under the conditions of a cylinder temperature of 300°C, a mold temperature of 110°C, and a molding cycle of 40 seconds to obtain test specimens for UL-94 with a length of 125 mm, a width of 13 mm, and a thickness of 1.5 mm.

[0072] <Evaluation of Flame Retardancy: UL-94 (for 1.5 mm thickness)> The UL test specimens obtained above were tested in accordance with the UL94 test (combustion test for plastic materials for parts of equipment) defined by Underwriters Laboratories (UL) in the United States. The combustion results were ranked from good to V-0, V-1, V-2, and those outside the specifications were classified as NR (not rated). In addition, the total combustion time is expressed in seconds as the total combustion time of 5 samples, i.e., after 10 flame contacts, in the 20 mm vertical combustion test of UL Standard 94. The total combustion time is preferably 50 seconds or less, more preferably 40 seconds or less, particularly preferably 30 seconds or less, and even more preferably 20 seconds or less.

[0073] <Preparation of ISO multi-purpose test piece (4 mm)> After drying the resin composition pellets obtained above at 120 °C for 4 hours, injection molding was carried out using an injection molding machine (NEX80III type) manufactured by Nissei Plastic Industrial Co., Ltd. under the conditions of a cylinder set temperature of 280 °C, a mold temperature of 80 °C, an injection time of 2 seconds, and a molding cycle of 50 seconds to obtain an ISO multi-purpose test piece (4 mm thick).

[0074] <Measurement of heat resistance (heat deflection temperature)> Using the ISO dumbbell piece (4 mm thick) obtained above, the heat deflection temperature (DTUL, unit: °C) was measured under the condition of a load of 1.80 MPa based on the ISO75 A method.

[0075] The above evaluation results are shown in Table 2 below. In the table, Ex. n represents Example n and Comp. n represents Comparative Example n.

[0076]

Table 2

Industrial Applicability

[0077] The polycarbonate resin composition of the present invention is a polycarbonate resin material that does not generate toxic gases during combustion, clears regulations such as PFAS, exhibits excellent flame retardancy at a low addition amount, and also has excellent heat resistance, so it can be suitably used for various molded products.

Claims

1. A flame-retardant polycarbonate resin composition comprising 100 parts by mass of a polycarbonate resin (A), 0.5 to 8 parts by mass of an expandable graphite (B), and 3 to 15 parts by mass of a silicone-based flame retardant (C).

2. 2. The resin composition according to claim 1, wherein the mass ratio of the content of the expandable graphite (B) to the content of the silicone-based flame retardant (C) is 0.01 to 0.

50.

3. 3. The resin composition according to claim 1, wherein the silicone-based flame retardant (C) has a melting point of 50°C or higher.

4. 3. The resin composition according to claim 1, further comprising a filler (D) in an amount of 1 to 90 parts by mass per 100 parts by mass of the polycarbonate resin (A).

5. 3. The resin composition according to claim 1, wherein the filler (D) is a glass fiber.

6. 3. The resin composition according to claim 1, further comprising a mold release agent (E) in an amount of 0.1 to 2 parts by mass per 100 parts by mass of the polycarbonate resin (A).

7. The resin composition according to claim 1 or 2, wherein UL-94 of a 1.5 mm thickness is V-0.

8. The resin composition according to claim 1 or 2, which has a deflection temperature under load of more than 130°C as measured in accordance with ISO 75 A method.

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

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

11. A molded article made from the pellets according to claim 9.

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