Flame-retardant polycarbonate resin composition

Abstract

To provide a flame-retardant polycarbonate resin composition which does not generate toxic fumes at the time of combustion, passes regulations for PFAS and the like, is an environmentally friendly advanced flame-retardant material, and has excellent heat resistance and impact resistance.　This flame-retardant polycarbonate resin composition is characterized by comprising, with respect to 100 mass parts of a polycarbonate resin (A), 0.1-2.5 mass parts of sepiolite (B), and 0.01-5 mass parts of an organic sulfonic acid metal salt (C).

Description

Flame-retardant polycarbonate resin composition

[0001] The present invention relates to a flame-retardant polycarbonate resin composition, and more particularly to a flame-retardant polycarbonate resin composition that satisfies PFAS regulations, is an environmentally friendly material, and yet has high flame retardancy and excellent mechanical properties.

[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 parts in industrial fields. 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, the trend toward flame retardancy has grown, leading to a demand for high levels of flame retardancy in polycarbonate resins, with many cases requiring a V-0 rating under the UL-94 testing method. Halogen-based and phosphorus-based flame retardants have been used to impart flame retardancy to polycarbonate resins. However, a relatively high addition rate of phosphorus-based flame retardants is required to achieve V-0 flame retardancy, which can easily reduce the mechanical performance of polycarbonate resin materials. Flame retardants using halogen-based bromine- or chlorine-based flame retardants are increasingly being banned due to the toxicity and environmental concerns of the harmful gases they emit.

[0004] In particular, fluorine-based flame retardants, such as perfluoroalkane metal salts proposed in Patent Documents 1 and 2, can achieve high flame retardancy with a relatively small amount. Furthermore, by incorporating such flame retardants 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, primarily in Japan, Europe, and the United States, and PFAS regulations on perfluoroalkyl compounds and polyfluoroalkyl compounds are being implemented primarily in the EU and the United States, including polyfluoroethylene. PFAS regulations are becoming even more stringent internationally.

[0005] Japanese Patent Publication No. 47-40445 Japanese Patent Publication No. 49-88943

[0006] Therefore, there is a strong demand for a highly functional flame-retardant polycarbonate resin composition that does not generate toxic gases during combustion, meets various regulations such as PFAS regulations, and is environmentally friendly. 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 further using polytetrafluoroethylene as a dripping inhibitor. The present invention has been made in light of the above circumstances, and its object (object) is to provide a polycarbonate resin composition that meets regulations such as PFAS and has high flame retardancy that is environmentally friendly.

[0007] The present inventors have conducted extensive research to achieve the above object, and as a result have found that the above object can be achieved by incorporating sepiolite and a metal salt of an organic sulfonate, thereby completing the present invention. The present invention relates to the following flame-retardant polycarbonate resin composition and molded article.

[0008] 1. A flame-retardant polycarbonate resin composition comprising 0.1 to 2.5 parts by mass of sepiolite (B) and 0.01 to 5 parts by mass of an organic sulfonic acid metal salt (C) per 100 parts by mass of polycarbonate resin (A). 2. The resin composition according to above 1, wherein the sepiolite (B) is sepiolite surface-treated with a silicone compound. 3. The resin composition according to above 1 or 2, wherein the organic sulfonic acid metal salt (C) is an aromatic sulfonic acid metal salt. 4. The resin composition according to any one of 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 above 4, wherein the filler (D) is a glass-based filler. 6. The resin composition according to above 5, wherein the glass-based filler is glass fiber. 7. 7. The resin composition according to any one of 1 to 6 above, further comprising 0.1 to 2 parts by mass of a release agent (E) relative to 100 parts by mass of the polycarbonate resin (A). 8. The resin composition according to any one of 1 to 7 above, wherein the content of sepiolite (B) is 0.1 part by mass or more and less than 1.0 part by mass relative to 100 parts by mass of the polycarbonate resin (A). 9. The resin composition according to any one of 1 to 8 above, wherein UL-94 of a 1.5 mm thickness is V-0. 10. Pellets of the resin composition according to any one of 1 to 9 above. 11. A molded article of the resin composition according to any one of 1 to 9 above. 12. A molded article of the pellets according to 10 above.

[0009] The flame-retardant polycarbonate resin composition of the present invention is a highly flame-retardant resin material that does not generate toxic gases during combustion and is environmentally friendly, meeting regulations such as PFAS, by blending low amounts of sepiolite and an organic sulfonate metal salt into a polycarbonate resin, and also has excellent heat resistance and impact resistance.

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

[0011] The flame-retardant polycarbonate resin composition of the present invention is characterized by containing 0.1 to 2.5 parts by mass of sepiolite (B) and 0.01 to 5 parts by mass of an organic sulfonic acid metal salt (C) per 100 parts by mass of 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 carbonate bonds are aromatic carbons, and aliphatic polycarbonate resins in which the carbons directly bonded to carbonate bonds are aliphatic carbons, and either 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 serve as 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-naphthyleethane, 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, bis(hydroxyaryl)alkanes such as 4,4-bis(4-hydroxyphenyl)heptane, 2,2-bis(4-hydroxyphenyl)nonane, 1,1-bis(4-hydroxyphenyl)decane, and 1,1-bis(4-hydroxyphenyl)dodecane;

[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, bis(hydroxyaryl)cycloalkanes such as 1,1-bis(4-hydroxyphenyl)-4-phenylcyclohexane;

[0018] Cardo structure-containing bisphenols such as 9,9-bis(4-hydroxyphenyl)fluorene and 9,9-bis(4-hydroxy-3-methylphenyl)fluorene;

[0019] Dihydroxydiaryl sulfides such as 4,4'-dihydroxydiphenyl sulfide and 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfide; dihydroxydiaryl sulfoxides such as 4,4'-dihydroxydiphenyl sulfoxide and 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfoxide; dihydroxydiaryl sulfones such as 4,4'-dihydroxydiphenyl sulfone and 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfone; and the like.

[0020] Of these, bis(hydroxyaryl)alkanes are preferred, and bis(4-hydroxyphenyl)alkanes are particularly preferred, with 2,2-bis(4-hydroxyphenyl)propane (i.e., bisphenol A) and 2,2-bis(3-methyl-4-hydroxyphenyl)propane (i.e., bisphenol C) being particularly preferred from the standpoints of impact resistance and heat resistance. The aromatic dihydroxy compounds may be used alone or in any combination and ratio of two or more.

[0021] Among the monomers serving 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; and haloformates such as bischloroformates of dihydroxy compounds and monochloroformates of dihydroxy compounds.

[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 higher effect of improving moist heat resistance, and the interfacial polymerization method is particularly preferred.

[0025] The molecular weight of the polycarbonate resin (A), as 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, and even more preferably 12,000 to 35,000, and particularly preferably 13,000 to 30,000. By adjusting 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. By adjusting 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, allowing for easier molding processability. Two or more polycarbonate resins having different viscosity average molecular weights may be mixed and used, in which case polycarbonate resins having viscosity average molecular weights outside the above preferred range may be mixed.

[0026] The viscosity average molecular weight [Mv] is determined by measuring the intrinsic viscosity [η] (unit: dl / g) at 25°C using methylene chloride as a solvent with an Ubbelohde viscometer, and then calculating the viscosity average molecular weight [Mv] 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.

[0027] In order to improve the appearance and flowability 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 a virgin raw material but also a polycarbonate resin recycled from used products (so-called material-recycled polycarbonate resin), and it is also preferable to contain both a virgin polycarbonate resin and a recycled polycarbonate resin, or it may consist of a recycled polycarbonate resin. When a recycled polycarbonate resin is contained, the proportion of the recycled polycarbonate resin in the polycarbonate resin (A) is preferably 30% or more, 40% or more, 50% or more, 60% or more, 70% or more, or 80% or more, and it is also preferable that the recycled polycarbonate resin is 100%.

[0029] [Sepiolite (B)] Sepiolite (B) is a type of clay mineral classified as a phyllosilicate mineral, and its chemical formula is Mg ８ Si １２ O ３０ (OH) ４ (OH ２ ) ４ ・8H ２ Sepiolite is a fibrous mineral consisting of discontinuous layers, and is characterized by its porous nature, large specific surface area, and high adsorption capacity for water and other substances.

[0030] The mechanism by which sepiolite exhibits flame retardancy is thought to be that when exposed to high heat such as flames, interlayer water and structural water are released, resulting in a cooling and diluting effect, and the fibrous structure of sepiolite reinforces the char that forms.

[0031] The sepiolite (B) is preferably surface-treated. Specific examples of surface-treating agents include silicone compounds such as organopolysiloxane, coupling agents such as silane coupling agents, titanate coupling agents, and aluminum coupling agents, alcohols such as trimethylolethane, trimethylolpropane, and pentaerythritol, alkanolamines such as triethylamine, higher fatty acids such as stearic acid, fatty acid metal salts such as calcium stearate and magnesium stearate, polyacrylates such as sodium polyacrylate and ammonium polyacrylate, hydrocarbon lubricants such as polyethylene wax and liquid paraffin, basic amino acids such as lysine and arginine, polyglycerin and derivatives thereof, etc. Among these, silicone compounds such as organopolysiloxane are preferred, as surface treatment with a silicone compound improves heat resistance and disperses well in polycarbonate resins, resulting in a significant improvement in flame retardancy.

[0032] Sepiolite is commercially available, and commercially available sepiolite can also be used as sepiolite (B).

[0033] The content of sepiolite (B) is 0.1 to 2.5 parts by mass per 100 parts by mass of polycarbonate resin (A), and good flame retardancy is achieved at such a low content. If the content is less than the lower limit, flame retardancy is insufficient, and if the content is greater than the upper limit, decomposition of the polycarbonate proceeds, making it difficult to achieve good flame retardancy. The content of sepiolite (B) per 100 parts by mass of polycarbonate resin (A) is preferably 0.11 parts by mass or more, more preferably 0.12 parts by mass or more, and more preferably 2.3 parts by mass or less, with 2.0 parts by mass or less, 1.8 parts by mass or less, 1.5 parts by mass or less, 1.3 parts by mass or less, 1.1 parts by mass or less, 1.0 parts by mass or less, less than 1.0 parts by mass, 0.9 parts by mass or less, 0.8 parts by mass or less, and particularly less than 0.8 parts by mass being preferred. By making the content equal to or less than the upper limit, decomposition of the resin is suppressed, and the deflection temperature under load at a thickness of 4.0 mm tends to improve.

[0034] [Organic Sulfonate Metal Salt (C)] The polycarbonate resin composition of the present invention contains an organic sulfonate metal salt (C). The organic sulfonate metal salt (C) is preferably a non-fluorine-based organic sulfonate metal salt flame retardant that does not have a C—F bond in the molecule.

[0035] The metal of the metal salt is preferably an alkali metal or alkaline earth metal, and examples thereof include alkali metals such as lithium (Li), sodium (Na), potassium (K), rubidium (Rb), and cesium (Cs); and alkaline earth metals such as magnesium (Mg), calcium (Ca), strontium (Sr), and barium (Ba). Of these, sodium, potassium, and cesium are preferred, with sodium and potassium being particularly preferred.

[0036] Preferred examples of the organic sulfonic acid metal salt (C) include metal salts of aromatic sulfonic acids, metal salts of aromatic sulfonamides (or sulfonimides), and metal salts of polystyrene sulfonic acids.

[0037] Specific examples of these include alkali metal salts of aromatic sulfonic acids having at least one aromatic group in the molecule, such as potassium 3-(phenylsulfonyl)benzenesulfonate (i.e., potassium diphenylsulfone-3-sulfonate), dipotassium diphenylsulfone-3,3'-disulfonate, sodium benzenesulfonate, potassium benzenesulfonate, cesium benzenesulfonate, sodium paratoluenesulfonate, potassium paratoluenesulfonate, cesium paratoluenesulfonate, sodium dodecylbenzenesulfonate, potassium dodecylbenzenesulfonate, cesium dodecylbenzenesulfonate, potassium styrenesulfonate, sodium polystyrenesulfonate, potassium polystyrenesulfonate, and cesium polystyrenesulfonate; and alkaline earth metal salts of aromatic sulfonic acids having at least one aromatic group in the molecule, such as magnesium paratoluenesulfonate, calcium paratoluenesulfonate, strontium paratoluenesulfonate, barium paratoluenesulfonate, magnesium dodecylbenzenesulfonate, and calcium dodecylbenzenesulfonate.

[0038] Examples of metal salts of aromatic sulfonamides (or sulfonimides) include potassium salts of N-(p-tolylsulfonyl)-p-toluenesulfonimide, potassium salts of N-(N'-benzylaminocarbonyl)sulfanilimide, and potassium salts of N-(phenylcarboxyl)-sulfanilimide.

[0039] Among the above, the organic sulfonic acid metal salt (C) is preferably a metal salt of paratoluenesulfonic acid, a metal salt of phenylsulfonylbenzenesulfonic acid, or a metal salt of polystyrenesulfonic acid, and among these, a metal salt, particularly an alkali metal salt, particularly a sodium salt or potassium salt, is preferred. The organic sulfonic acid metal salt (C) may be used alone or in any combination and ratio of two or more.

[0040] The content of the organic sulfonic acid metal salt (C) is 0.01 to 5 parts by mass, and preferably 0.02 parts by mass or more, more preferably 0.03 parts by mass or more, 0.05 parts by mass or more, 0.08 parts by mass or more, or 0.1 parts by mass or more, relative to 100 parts by mass of the polycarbonate resin (A), and is also preferably 4 parts by mass or less, more preferably 3 parts by mass or less, and even more preferably 2 parts by mass or less, 1.5 parts by mass or less, 1.0 parts by mass or less, 0.7 parts by mass or less, 0.5 parts by mass or less, 0.4 parts by mass or less, 0.3 parts by mass or less, and particularly preferably 0.2 parts by mass or less. The mass ratio (C / B) of the organic sulfonic acid metal salt (C) to the sepiolite (B) is 0.06 to 1.9, preferably 0.075 or more, 0.1 or more, 0.2 or more, or 0.3 or more, and preferably 1.75 or less, more preferably 1.5 or less, 1.25 or less, or 1.1 or less. By doing so, a polycarbonate resin composition can be obtained that satisfies PFAS regulations and achieves V-0 flame retardancy with a low additive amount, and the mechanical properties and thermal characteristics are also improved.

[0041] It is preferable that the polycarbonate resin composition of the present invention is substantially free of phosphorus-based flame retardants or halogen-based flame retardants. Here, "substantially free" means that the amount of the phosphorus-based flame retardant and / or halogen-based flame retardant, 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.

[0042] [Filler (D)] The polycarbonate resin composition of the present invention preferably further contains a filler (D). The filler (D) is preferably contained in an amount of 1 to 90 parts by mass per 100 parts by mass of the polycarbonate resin (A). By including the filler (D) together with the sepiolite (B) and the organic sulfonic acid metal salt (C), the flame retardancy provided by the sepiolite (B) and the organic sulfonic acid metal salt (C) and the drip prevention ability provided by the filler (D) can be balanced to achieve a higher level of flame retardancy. The content of the filler (D) is more preferably 3 parts by mass or more, particularly 5 parts by mass or more, 7 parts by mass or more, 10 parts by mass or more, or 15 parts by mass or more, and more preferably 80 parts by mass or less, particularly 75 parts by mass or less, 70 parts by mass or less, 65 parts by mass or less, 60 parts by mass or less, or 50 parts by mass or less, per 100 parts by mass of the polycarbonate resin (A). The filler (D) may be contained in one kind or in two or more kinds.

[0043] 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. The acicular inorganic filler is an inorganic filler having a whisker-like, columnar, or other shape, and examples thereof include wollastonite. The fibrous inorganic filler refers to a thin and long fibrous inorganic filler, and examples thereof include glass fiber, ceramic fiber, and carbon fiber. Examples of the shape of the fibrous inorganic filler include chopped strands and milled fibers. The plate-like inorganic filler is an inorganic filler having a flake-like, scale-like, or other shape, and examples thereof include talc, mica, and glass flakes.

[0044] 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 more 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.

[0045] 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. Examples of glass flakes include scale-like glass flakes with a thickness of 0.5 to 20 μm and a side length of 0.05 to 1.0 mm.

[0046] 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 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 resin capable of forming a film, such as an epoxy resin or urethane resin, or a mixture of a resin capable of forming a film with a heat stabilizer, a flame retardant, or the like.

[0047] [Release Agent (E)] The resin composition of the present invention preferably contains a release agent (E). Examples of the release agent (E) include aliphatic carboxylic acids, esters of aliphatic carboxylic acids and alcohols, aliphatic hydrocarbons having a number average molecular weight of 200 to 15,000, and polysiloxane-based silicone oils.

[0048] 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, tetraliacontanoic acid, montanic acid, adipic acid, and azelaic acid.

[0049] 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.

[0050] 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.

[0051] The ester may contain an aliphatic carboxylic acid and / or alcohol as an impurity. The ester may be a pure substance or a mixture of multiple compounds. The aliphatic carboxylic acid and alcohol that combine to form an ester may each be used alone or in any combination and ratio of two or more.

[0052] 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.

[0053] 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 partial oxides of polyethylene wax are preferred, with paraffin wax and polyethylene wax being more preferred. The number-average molecular weight of the aliphatic hydrocarbons is preferably 5,000 or less. The aliphatic hydrocarbon may be a single substance, or a mixture of substances with various constituent components and molecular weights may be used as long as the main component is within the above-mentioned range.

[0054] Examples of polysiloxane-based silicone oils include dimethyl silicone oil, methylphenyl silicone oil, diphenyl silicone oil, and fluorinated alkyl silicone.

[0055] The above-mentioned release agents may be contained alone or in any combination and ratio of two or more.

[0056] The content of the release agent (E) is preferably 0.1 to 2 parts by mass, more preferably 1 part by mass or less, even more preferably 0.8 parts by mass or less, and particularly preferably 0.5 parts by mass or less, per 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, there is a possibility that the hydrolysis resistance will decrease and the mold will be contaminated during injection molding.

[0057] [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.

[0058] Any known phosphorus-based 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.

[0059] Examples of the organic phosphite compound include triphenyl phosphite, tris(mononylphenyl)phosphite, tris(mononyl / dinonyl phenyl)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 SE. One type of phosphorus-based stabilizer may be contained, or two or more types may be contained in any combination and ratio.

[0060] 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 less than 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.

[0061] 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- 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.

[0062] Of 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 hindered phenol-based antioxidants include "Irganox 1010" and "Irganox 1076" manufactured by BASF, and "Adekastab AO-50" and "Adekastab AO-60" manufactured by ADEKA. One type of phenol-based stabilizer may be contained, or two or more types may be contained in any combination and ratio.

[0063] 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 part by mass or less, per 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.

[0064] [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.

[0065] It is also possible to contain a resin other than the polycarbonate resin (A) in an amount less than that of the polycarbonate resin (A). 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 relative to 100 parts by mass of the polycarbonate resin (A), and more 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. In particular, when a polybutylene terephthalate resin is contained, the content thereof is preferably 45 parts by mass or less relative to 100 parts by mass of the polycarbonate resin (A), and more 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.

[0066] [Polycarbonate Resin Composition] The polycarbonate resin composition of the present invention has high flame retardancy and can achieve V-0 in a 1.5 mm thick UL test piece in the UL-94 test. The polycarbonate resin composition of the present invention also has excellent impact resistance and preferably has an unnotched Charpy impact strength of 50 kJ / m or more at a 4.0 mm thick test piece. ２ More preferably, 55 kJ / m ２ More preferably, 57 kJ / m ２ More than 59 kJ / m ２The polycarbonate resin composition of the present invention is also excellent in heat resistance, and has a deflection temperature under load of 1.80 MPa at a thickness of 4.0 mm of 135°C or higher, preferably 140°C or higher, more preferably 143°C or higher, 144°C or higher, and particularly preferably 145°C or higher.

[0067] The polycarbonate resin composition of the present invention is molded into a molded article. The molded article can be produced by 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 or other hollow molding methods, molding using an insulated mold, molding using a rapidly heated mold, foam molding (including supercritical fluids), 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.

[0068] [Molded Article] Examples of molded articles include parts for electric / electronic devices, office automation equipment, information terminal devices, machine parts, home appliances, vehicle parts, building materials, various containers, leisure goods / miscellaneous goods, lighting equipment, etc. Among these, the molded articles are suitable for use in parts for electric / electronic devices, office automation equipment, information terminal devices, 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.

[0069] The present invention will be described in more detail below with reference to examples. However, the present invention should not be construed as being limited to the following examples. The components used in the examples and comparative examples are as shown in Table 1 below.

[0070]

[0071] (Examples 1 to 10, Comparative Examples 1 to 6) <Production of Resin Composition Pellets> Of the above-mentioned components, all except filler (D) were blended in the proportions (parts by mass) shown in Tables 2 and 3 below, and mixed in a tumbler for 20 minutes. The mixture was then supplied to a twin-screw extruder "TEX30α" equipped with one vent, manufactured by The Japan Steel Works, Ltd., and kneaded under conditions of a screw rotation speed of 200 rpm, a discharge rate of 25 kg / hr, and a barrel temperature of 280°C, while further feeding filler (D) in the proportion (parts by mass) shown in Tables 2 and 3 below from the middle of the barrel using a side feeder. The molten resin extruded in the form of strands was quenched in a water tank and pelletized using a pelletizer to obtain pellets of a polycarbonate resin composition.

[0072] <Preparation of UL-94 Test Piece> The resin composition pellets obtained by the above-mentioned production method were dried at 120°C for 4 hours, and then injection molded using an SE100DU injection molding machine manufactured by Sumitomo Heavy Industries, Ltd. under conditions of a cylinder temperature of 300°C, a mold temperature of 110°C, and a molding cycle of 40 seconds to obtain a UL-94 test piece having a length of 125 mm, a width of 13 mm, and a thickness of 1.5 mm.

[0073] <Evaluation of Flame Retardancy: UL-94 (1.5 mmt)> The UL test specimens obtained above were tested in accordance with the UL94 test (flammability test for plastic materials for equipment parts) established by Underwriters Laboratories (UL) in the U.S. Flammability results were rated V-0, V-1, and V-2 in descending order, with those that did not meet the standard being NR (not rated).

[0074] <Preparation of ISO multipurpose test piece (4 mm)> The resin composition pellets obtained above were dried at 120°C for 4 hours, and then injection molded into ISO multipurpose test pieces (4 mm thick) using an injection molding machine (NEX80III type) manufactured by Nissei Plastic Industrial Co., Ltd. under the conditions of a cylinder setting temperature of 280°C, a mold temperature of 80°C, an injection time of 2 seconds, and a molding cycle of 50 seconds.

[0075] <Measurement of Heat Resistance (Deflection Temperature Under Load)> Using the ISO multipurpose test specimen (thickness 4 mm) obtained above, the deflection temperature under load (DTUL, unit: ° C.) was measured under a load of 1.80 MPa according to ISO 75 Method A.

[0076] <Measurement of Unnotched Charpy Impact Strength> Using the ISO multipurpose test piece (4 mmt) obtained by the above method, the unnotched Charpy impact strength (unit: kJ / m) was measured in accordance with ISO179-1 and ISO179-2. ２ If the test piece was not broken in this measurement, it was recorded as NB (No Break).

[0077] <Measurement of Flexural Modulus> Using the ISO multipurpose test piece (4 mmt) obtained by the method described above, the flexural modulus (unit: GPa) was measured in accordance with ISO178.

[0078] The results are shown in Tables 2 and 3. In the tables, Actual n is Example n, and Relative n is Comparative Example n.

[0079]

[0080]

[0081] The polycarbonate resin composition of the present invention is a polycarbonate resin material that does not generate toxic gases when burned, meets regulations such as PFAS, exhibits excellent flame retardancy even with a small amount added, and has excellent mechanical properties, and therefore can be suitably used for various molded articles.

Claims

1. A flame-retardant polycarbonate resin composition comprising 100 parts by mass of polycarbonate resin (A), 0.1 to 2.5 parts by mass of sepiolite (B), and 0.01 to 5 parts by mass of an organic sulfonic acid metal salt (C).

2. The resin composition according to claim 1, wherein the sepiolite (B) is sepiolite whose surface has been treated with a silicone compound.

3. The resin composition according to claim 1 or 2, wherein the organic metal sulfonate (C) is an aromatic metal sulfonate.

4. The resin composition according to claim 1 or 2, 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 claim 4, wherein the filler (D) is a glass-based filler.

6. The resin composition according to claim 5, wherein the glass filler is glass fiber.

7. The resin composition according to claim 1 or 2, 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).

8. The resin composition according to claim 1 or 2, wherein the content of sepiolite (B) is 0.1 part by mass or more and less than 1.0 part by mass per 100 parts by mass of the polycarbonate resin (A).

9. The resin composition according to claim 1 or 2, wherein the UL-94 rating of a 1.5 mm thick sheet is V-0.

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

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

12. A molded product made from the pellets of claim 10.

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