Aromatic polycarbonate resin composition and molded article thereof

Abstract

This aromatic polycarbonate resin composition contains, relative to 100 parts by weight of (A) an aromatic polycarbonate resin (component A), 0.02-0.04 parts by weight of (B) an epoxy group-containing compound (component B), and 0.06-0.15 parts by weight of (C) a glycerol mono-fatty acid ester (component C), the resin composition being characterized by having excellent moist-heat resistance and molding heat resistance.

Description

[Technical field]

[0001] The present invention relates to an aromatic polycarbonate resin composition having excellent resistance to moist heat and molding heat, and a molded article thereof. [Background technology]

[0002] Aromatic polycarbonate resins are polymeric materials that have relatively excellent heat resistance, but as the demand for higher functionality and performance of materials increases, there is a need for further improvements in their resistance to moist heat and molding heat.

[0003] A technique for using a fatty acid ester and an epoxy compound in combination is known from Patent Document 1. However, the ester of pentaerythritol and an aliphatic carboxylic acid shown in the examples has insufficient moist heat resistance, and the amount of glycerin mono fatty acid ester added shown in the comparative examples has insufficient molding heat resistance.

[0004] In Patent Document 2, the amount of the epoxy group-containing compound added shown in the examples is 0.0075 parts by mass or less per 100 parts by weight of polycarbonate resin, and in this addition range, the moist heat resistance is insufficient.

[0005] In Patent Documents 3 and 4, the amount of glycerin monofatty acid ester added is 0.05 parts by mass or less, and there are problems with moldability due to insufficient mold releasability. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent No. 5542810 [Patent Document 2] JP 2020-132840 A [Patent Document 3] Patent Publication No. 2021-134286 [Patent Document 4] JP 2021-120458 A DISCLOSURE OF THEINVENTION [Problem to be solved by the invention]

[0007] An object of the present invention is to provide an aromatic polycarbonate resin composition having excellent resistance to moist heat and molding heat, and a molded article thereof. [Means for solving the problem]

[0008] Means for Solving the Problems The present inventors have conducted intensive research to solve the above problems, and as a result have found that an aromatic polycarbonate resin composition comprising an aromatic polycarbonate resin, an epoxy group-containing compound, and a glycerin monofatty acid ester in a specific ratio, and a molded article thereof can achieve the above objects, thereby completing the present invention.

[0009] That is, according to the present invention, the following (Configuration 1) to (Configuration 4) are provided. (Configuration 1) A polycarbonate resin composition comprising 100 parts by weight of (A) an aromatic polycarbonate resin (component A), 0.02 to 0.04 parts by weight of (B) an epoxy group-containing compound (component B), and 0.06 to 0.15 parts by weight of (C) a glycerin monofatty acid ester (component C). (Configuration 2) The resin composition according to configuration 1, comprising 0.01 to 0.02 parts by weight of an aromatic phosphite ester-based heat stabilizer (D) (Component D) per 100 parts by weight of Component A. (Configuration 3) 3. The resin composition according to claim 1, wherein the component B is a copolymer of styrene and glycidyl methacrylate. (Configuration 4) A molded article formed from the aromatic polycarbonate resin composition according to any one of claims 1 to 3. Effect of the Invention

[0010] The aromatic polycarbonate resin composition of the present invention has excellent resistance to moist heat and molding heat, and can therefore be used in a variety of applications in which aromatic polycarbonate resin compositions are used, and is of great industrial value. BEST MODE FOR CARRYING OUT THEINVENTION

[0011] The present invention will be described in detail below. <Aromatic polycarbonate resin (Component A)> The aromatic polycarbonate resin used as component (A) in the present invention is, for example, one obtained by reacting a dihydric phenol with a carbonate precursor by an interfacial polymerization method (solution method) or a melt method.

[0012] Representative examples of the dihydric phenols used herein include hydroquinone, resorcinol, 4,4'-dihydroxydiphenyl, 1,4-dihydroxynaphthalene, bis(4-hydroxyphenyl)methane, bis{(4-hydroxy-3,5-dimethyl)phenyl}methane, 1,1-bis(4-hydroxyphenyl)ethane, 1,1-bis(4-hydroxyphenyl)-1-phenylethane, 2,2-bis(4-hydroxyphenyl)propane (commonly known as bisphenol A), 2,2-bis{(4-hydroxy-3-methyl)phenyl}propane, 2 ,2-bis{(4-hydroxy-3,5-dimethyl)phenyl}propane, 2,2-bis{(3,5-dibromo-4-hydroxy)phenyl}propane, 2,2-bis{(3-isopropyl-4-hydroxy)phenyl}propane, 2,2-bis{(4-hydroxy-3-phenyl)phenyl}propane, 2,2-bis(4-hydroxyphenyl)butane, 2,2-bis(4-hydroxyphenyl)-3-methylbutane, 2,2-bis(4-hydroxyphenyl)-3,3-dimethylbutane, 2,4-bis(4-hydroxyphenyl)-2-methylbutane tungsten, 2,2-bis(4-hydroxyphenyl)pentane, 2,2-bis(4-hydroxyphenyl)-4-methylpentane, 1,1-bis(4-hydroxyphenyl)cyclohexane, 1,1-bis(4-hydroxyphenyl)-4-isopropylcyclohexane, 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane, 9,9-bis(4-hydroxyphenyl)fluorene, 9,9-bis{(4-hydroxy-3-methyl)phenyl}fluorene, α,α'-bis(4-hydroxyphenyl)-o-diisopropyl Examples of such hydroxydiphenyl ethers include benzene, α,α'-bis(4-hydroxyphenyl)-m-diisopropylbenzene, α,α'-bis(4-hydroxyphenyl)-p-diisopropylbenzene, 1,3-bis(4-hydroxyphenyl)-5,7-dimethyladamantane, 4,4'-dihydroxydiphenyl sulfone, 4,4'-dihydroxydiphenyl sulfoxide, 4,4'-dihydroxydiphenyl sulfide, 4,4'-dihydroxydiphenyl ketone, 4,4'-dihydroxydiphenyl ether, and 4,4'-dihydroxydiphenyl ester.Preferred dihydric phenols are bis(4-hydroxyphenyl)alkanes, with bisphenol A being particularly preferred.

[0013] The carbonate precursor may be a carbonyl halide, a carbonate ester or a haloformate, and specific examples thereof include phosgene, diphenyl carbonate or a dihaloformate of a dihydric phenol.

[0014] When the dihydric phenol and the carbonate precursor are reacted by the interfacial polymerization method or the melting method to produce the aromatic polycarbonate resin, the dihydric phenol may be used alone or in combination of two or more kinds, and a catalyst, a terminal terminator, an antioxidant for the dihydric phenol, etc. may be used as necessary. The aromatic polycarbonate resin may be a branched polycarbonate resin copolymerized with a trifunctional or higher polyfunctional aromatic compound. It may also be a mixture of two or more kinds of aromatic polycarbonate resins.

[0015] The reaction by the interfacial polymerization method is usually a reaction between a dihydric phenol and phosgene, and is carried out in the presence of an acid binder and an organic solvent. As the acid binder, for example, an alkali metal hydroxide such as sodium hydroxide or potassium hydroxide, or an amine compound such as pyridine is used. As the organic solvent, for example, a halogenated hydrocarbon such as methylene chloride or chlorobenzene is used. In addition, a catalyst such as a tertiary amine or a quaternary ammonium salt can be used to promote the reaction. In this case, the reaction temperature is usually 0 to 40°C, and the reaction time is about several minutes to 5 hours.

[0016] The reaction by the melting method is usually a transesterification reaction between dihydric phenol and diphenyl carbonate. Dihydric phenol and diphenyl carbonate are mixed in the presence of an inert gas and reacted under reduced pressure, usually at 120 to 350°C. The degree of pressure reduction is changed stepwise, and finally it is reduced to 1.3 x 10 2 The generated phenols are removed from the system by lowering the pressure to below Pa. The reaction time is usually about 1 to 4 hours.

[0017] In addition, in the polymerization reaction, monofunctional phenols can be used as a terminal terminator. In particular, in the case of a reaction using phosgene as a carbonate precursor, monofunctional phenols are generally used as terminal terminators to adjust the molecular weight, and the obtained aromatic polycarbonate resin has excellent thermal stability compared to those not having the terminals blocked by groups based on monofunctional phenols. Such monofunctional phenols may be any that are used as terminal terminators for polycarbonates, and are generally phenol or lower alkyl-substituted phenols, and can be monofunctional phenols represented by the following formula (1).

[0018] [ka]

[0019] [In the formula, R is a hydrogen atom or an alkyl group or a phenylalkyl group having 1 to 9 carbon atoms, and m is an integer of 1 to 5, preferably 1 to 3.] Specific examples of the monofunctional phenols include phenol, p-tert-butylphenol, p-cumylphenol, and isooctylphenol.

[0020] The molecular weight of the aromatic polycarbonate resin in the present invention is preferably a viscosity average molecular weight (M) of 10,000 to 50,000, more preferably 14,000 to 35,000. An aromatic polycarbonate resin having such a viscosity average molecular weight is preferred because it maintains relatively good fluidity during extrusion and molding processing, while providing a certain level of mechanical strength to the resulting molded product.

[0021] The viscosity average molecular weight of the aromatic polycarbonate resin in the present invention is determined by first calculating the specific viscosity (η SP ) was measured at 20°C using an Ostwald viscometer from a solution of 0.7 g of polycarbonate resin material dissolved in 100 ml of methylene chloride. Specific viscosity (η SP )=(tt 0 ) / t 0 [t 0 is the time it takes for methylene chloride to fall, and t is the time it takes for the sample solution to fall] The specific viscosity (η SP ) and the viscosity average molecular weight Mv was calculated using the following formula:

[0022] η SP / c=[η]+0.45×[η] 2 c (where [η] is the intrinsic viscosity) [η]=1.23×10 -4 Mv 0.83 c=0.7 <Epoxy group-containing compound (component B)> The epoxy group-containing compound used in the present invention is blended mainly for the purpose of improving the wet heat resistance, and basically any compound having an epoxy functional group can be used.

[0023] Specific examples of preferred epoxy group-containing compounds include 3,4-epoxycyclohexylmethyl-3',4'-epoxycyclohexylcarboxylate, 1,2-epoxy-4-(2-oxiranyl)cyclohexane adduct of 2,2-bis(hydroxymethyl)-1-butanol, copolymer of methyl methacrylate and glycidyl methacrylate, copolymer of styrene and glycidyl methacrylate, etc. Preferred are copolymers containing glycidyl groups, more preferably copolymers of styrene and glycidyl methacrylate. Commercially available copolymers of styrene and glycidyl methacrylate include Marproof G-0250SP manufactured by NOF Corporation.

[0024] The amount of the epoxy group-containing compound used in the present invention is 0.02 to 0.04 parts by weight, preferably 0.02 to 0.03 parts by weight, based on 100 parts by weight of the aromatic polycarbonate resin. Within the above range, the moisture heat resistance and molding heat resistance are good. <Glycerin mono fatty acid ester (ingredient C)> The glycerin mono-fatty acid ester used in the present invention is a condensation product of an aliphatic monocarboxylic acid and glycerin. The aliphatic monocarboxylic acid may be a saturated or unsaturated aliphatic monocarboxylic acid, and the aliphatic monocarboxylic acid may be either a chain aliphatic monocarboxylic acid or a cyclic aliphatic monocarboxylic acid, but a chain aliphatic monocarboxylic acid is preferred. The carbon number of the aliphatic monocarboxylic acid is preferably 6 to 40, more preferably 8 to 32, and even more preferably 12 to 24.

[0025] Examples of saturated aliphatic monocarboxylic acids include capric acid, neodecanoic acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, behenic acid, and lignoceric acid. Examples of unsaturated aliphatic carboxylic acids include undecylenic acid, oleic acid, elaidic acid, erucic acid, nervonic acid, linoleic acid, γ-linolenic acid, arachidonic acid, α-linolenic acid, stearidonic acid, eicosapentaenoic acid, and docosahexaenoic acid.

[0026] Among the above, preferred aliphatic monocarboxylic acids are lauric acid, myristic acid, palmitic acid, stearic acid, and behenic acid, more preferred are palmitic acid, stearic acid, and behenic acid, and even more preferred is stearic acid.

[0027] The glycerin mono-fatty acid ester used in the present invention is preferably glycerin monostearate. An example of a commercially available glycerin monostearate is Rikemal S-100A manufactured by Riken Vitamin Co., Ltd.

[0028] The amount of the glycerin monofatty acid ester used in the present invention is 0.06 to 0.15 parts by weight, preferably 0.07 to 0.13 parts by weight, and more preferably 0.09 to 0.11 parts by weight, based on 100 parts by weight of the aromatic polycarbonate resin. Within the above range, the mold releasability, moist heat resistance, and molding heat resistance are good. <Aromatic phosphite ester heat stabilizer (Component D)> Examples of aromatic phosphite-based heat stabilizers preferably used in the present invention include triaryl phosphites such as triphenyl phosphite, tricresyl phosphite, tris(ethylphenyl)phosphite, tris(2,4-di-t-butylphenyl)phosphite, tris(nonylphenyl)phosphite, and tris(hydroxyphenyl)phosphite; and aryl alkyl phosphites such as phenyl didecyl phosphite, diphenyl decyl phosphite, diphenyl isooctyl phosphite, phenyl isooctyl phosphite, and 2-ethylhexyl diphenyl phosphite. Among aromatic phosphite-based heat stabilizers, tris(2,4-di-tert.-butylphenyl)phosphite is preferred. Commercially available tris(2,4-di-tert.-butylphenyl)phosphite products include Irgafos168 manufactured by BASF.

[0029] The amount of the aromatic phosphite ester heat stabilizer preferably used in the present invention is preferably 0.01 to 0.02 parts by weight, more preferably 0.012 to 0.018 parts by weight, and even more preferably 0.014 to 0.016 parts by weight, based on 100 parts by weight of the aromatic polycarbonate resin. When it is within the above range, the moisture heat resistance and molding heat resistance are excellent. (Other additives) In order to improve the flame retardancy, antioxidant property, and light stability (ultraviolet light stability) of the resin composition of the present invention, additives used for these purposes are advantageously used. These additives will be specifically described below. (I) Flame retardants The resin composition of the present invention may contain various compounds known as flame retardants for polycarbonate resins. The incorporation of such compounds improves flame retardancy, but also improves antistatic properties, fluidity, rigidity, and thermal stability, etc., based on the properties of each compound. Examples of such flame retardants include (i) organometallic salt-based flame retardants (e.g., organic sulfonic acid alkali (earth) metal salts, organic boric acid metal salt-based flame retardants, and organic stannic acid metal salt-based flame retardants), (ii) organophosphorus-based flame retardants (e.g., organic group-containing monophosphate compounds, phosphate oligomer compounds, phosphonate oligomer compounds, phosphonitrile oligomer compounds, and phosphonic acid amide compounds), (iii) silicone-based flame retardants made of silicone compounds, and (iv) fibrillated PTFE, among which organometallic salt-based flame retardants and organophosphorus-based flame retardants are preferred. (i) Organometallic salt flame retardants The organic metal salt compound is preferably an alkali (earth) metal salt of an organic acid having 1 to 50 carbon atoms, preferably 1 to 40 carbon atoms, and is preferably an alkali (earth) metal salt of an organic sulfonate. The alkali (earth) metal salt of an organic sulfonate includes a metal salt of a fluorine-substituted alkylsulfonic acid, such as a metal salt of a perfluoroalkylsulfonic acid having 1 to 10 carbon atoms, preferably 2 to 8 carbon atoms, and an alkali metal or alkaline earth metal, and a metal salt of an aromatic sulfonic acid having 7 to 50 carbon atoms, preferably 7 to 40 carbon atoms, and an alkali metal or alkaline earth metal. Examples of the alkali metal constituting the metal salt include lithium, sodium, potassium, rubidium, and cesium, and examples of the alkaline earth metal include beryllium, magnesium, calcium, strontium, and barium. More preferred are alkali metals. Among these alkali metals, rubidium and cesium, which have a larger ionic radius, are preferred when a higher transparency is required, but these are not versatile and are difficult to purify, which may result in a disadvantage in terms of cost. On the other hand, metals with smaller ionic radii such as lithium and sodium may be disadvantageous in terms of flame retardancy. Taking these into consideration, the alkali metals in the alkali metal sulfonates can be selected appropriately, but in all respects, potassium sulfonates, which have an excellent balance of properties, are most suitable. Such potassium salts can also be used in combination with alkali metal sulfonates made of other alkali metals.

[0030] Specific examples of the alkali metal salt of perfluoroalkylsulfonate include potassium trifluoromethanesulfonate, potassium perfluorobutanesulfonate, potassium perfluorohexanesulfonate, potassium perfluorooctane sulfonate, sodium pentafluoroethanesulfonate, sodium perfluorobutanesulfonate, sodium perfluorooctane sulfonate, lithium trifluoromethanesulfonate, lithium perfluorobutanesulfonate, lithium perfluoroheptanesulfonate, cesium trifluoromethanesulfonate, cesium perfluorobutanesulfonate, cesium perfluorooctane sulfonate, cesium perfluorohexanesulfonate, rubidium perfluorobutanesulfonate, and rubidium perfluorohexanesulfonate, and these can be used alone or in combination of two or more. Here, the carbon number of the perfluoroalkyl group is preferably in the range of 1 to 18, more preferably in the range of 1 to 10, and even more preferably in the range of 1 to 8. Among these, potassium perfluorobutanesulfonate is particularly preferred. In the alkali (earth) metal salt of perfluoroalkylsulfonic acid made of an alkali metal, fluoride ions (F-) are usually mixed in no small amount. The presence of such fluoride ions can be a factor in reducing flame retardancy, so it is preferable to reduce them as much as possible. The proportion of such fluoride ions can be measured by ion chromatography. The content of fluoride ions is preferably 100 ppm or less, more preferably 40 ppm or less, and particularly preferably 10 ppm or less. It is also preferable that the content is 0.2 ppm or more for production efficiency. The alkali (earth) metal salt of perfluoroalkylsulfonic acid having a reduced amount of fluoride ions can be produced by using a known production method, and by a method of reducing the amount of fluoride ions contained in the raw material when producing a fluorine-containing organic metal salt, a method of removing hydrogen fluoride obtained by the reaction by gas generated during the reaction or by heating, and a method of reducing the amount of fluoride ions by using a purification method such as recrystallization and reprecipitation when producing a fluorine-containing organic metal salt.In particular, since organometallic salt flame retardants are relatively soluble in water, it is preferable to manufacture them using ion-exchanged water, particularly water that has an electrical resistance of 18 MΩ cm or more, i.e., an electrical conductivity of approximately 0.55 μS / cm or less, by dissolving and washing the material at a temperature higher than room temperature, and then cooling and recrystallizing the material.

[0031] Specific examples of the aromatic sulfonic acid alkali (earth) metal salts include disodium diphenyl sulfide-4,4'-disulfonate, dipotassium diphenyl sulfide-4,4'-disulfonate, potassium 5-sulfoisophthalate, sodium 5-sulfoisophthalate, polysodium polyethylene terephthalate polysulfonate, calcium 1-methoxynaphthalene-4-sulfonate, disodium 4-dodecylphenyl ether disulfonate, polysodium poly(2,6-dimethylphenylene oxide) polysulfonate, polysodium poly(1,3-phenylene oxide) polysulfonate, polysodium poly(1,4-phenylene oxide) polysulfonate, polypotassium poly(2,6-diphenylphenylene oxide) polysulfonate, lithium poly(2-fluoro-6-butylphenylene oxide) polysulfonate, potassium sulfonate of benzenesulfonate, sodium benzenesulfonate, and benzenesulfonic acid. Examples of the sulfonate include strontium, magnesium benzenesulfonate, dipotassium p-benzenedisulfonate, dipotassium naphthalene-2,6-disulfonate, calcium biphenyl-3,3'-disulfonate, sodium diphenylsulfone-3-sulfonate, potassium diphenylsulfone-3-sulfonate, dipotassium diphenylsulfone-3,3'-disulfonate, dipotassium diphenylsulfone-3,4'-disulfonate, sodium α,α,α-trifluoroacetophenone-4-sulfonate, dipotassium benzophenone-3,3'-disulfonate, disodium thiophene-2,5-disulfonate, dipotassium thiophene-2,5-disulfonate, calcium thiophene-2,5-disulfonate, sodium benzothiophenesulfonate, potassium diphenylsulfoxide-4-sulfonate, a formalin condensate of sodium naphthalenesulfonate, and a formalin condensate of sodium anthracenesulfonate. Of these alkali (earth) metal salts of aromatic sulfonic acid, potassium salts are particularly preferred.Among these alkali (earth) metal salts of aromatic sulfonates, potassium diphenylsulfone-3-sulfonate and dipotassium diphenylsulfone-3,3'-disulfonate are preferred, and a mixture thereof (wherein the weight ratio of the former to the latter is 15 / 85 to 30 / 70) is particularly preferred.

[0032] Suitable examples of organic metal salts other than alkali (earth) metal sulfonates include alkali (earth) metal salts of sulfates and alkali (earth) metal salts of aromatic sulfonamides. Examples of alkali (earth) metal salts of sulfates include alkali (earth) metal salts of sulfates of monohydric and / or polyhydric alcohols, and examples of sulfates of monohydric and / or polyhydric alcohols include methyl sulfate, ethyl sulfate, lauryl sulfate, hexadecyl sulfate, sulfate of polyoxyethylene alkylphenyl ether, mono-, di-, tri-, and tetrasulfate of pentaerythritol, sulfate of lauric acid monoglyceride, sulfate of palmitic acid monoglyceride, and sulfate of stearic acid monoglyceride. Examples of the alkali (earth) metal salts of these sulfates include alkali (earth) metal salts of lauryl sulfate. Examples of the alkali (earth) metal salt of aromatic sulfonamide include saccharin, N-(p-tolylsulfonyl)-p-toluenesulfonimide, N-(N'-benzylaminocarbonyl)sulfanilimide, and alkali (earth) metal salt of N-(phenylcarboxyl)sulfanilimide. The content of the organic metal salt flame retardant is preferably 0.001 to 1 part by weight, more preferably 0.005 to 0.5 parts by weight, further preferably 0.01 to 0.3 parts by weight, and particularly preferably 0.03 to 0.15 parts by weight, relative to 100 parts by weight of component A. (ii) Organophosphorus flame retardants As the organic phosphorus flame retardant, an aryl phosphate compound is suitable. This is because such phosphate compounds generally have excellent color. In addition, since phosphate compounds have a plasticizing effect, they are advantageous in that they can improve molding processability. As such a phosphate compound, various phosphate compounds known as conventional flame retardants can be used. The amount of the organic phosphorus flame retardant to be blended is preferably 0.01 to 20 parts by weight, more preferably 2 to 10 parts by weight, and even more preferably 2 to 7 parts by weight, relative to 100 parts by weight of component A. (II) Hindered phenol stabilizers The resin composition of the present invention may further contain a hindered phenol-based stabilizer. Such incorporation exerts an effect of suppressing deterioration of hue during molding processing and deterioration of hue over long-term use. Examples of the hindered phenol-based stabilizer include α-tocopherol, butyl hydroxytoluene, sinapyl alcohol, vitamin E, n-octadecyl-β-(4'-hydroxy-3',5'-di-tert-butylphenyl)propionate, 2-tert-butyl-6-(3'-tert-butyl-5'-methyl-2'-hydroxybenzyl)-4-methylphenyl acrylate, 2,6-di-tert-butyl-4-(N,N-dimethylaminomethyl)phenol, 3,5-di-tert-butyl 2,2'-methylenebis(4-methyl-6-tert-butylphenol), 2,2'-methylenebis(4-ethyl-6-tert-butylphenol), 4,4'-methylenebis(2,6-di-tert-butylphenol), 2,2'-methylenebis(4-methyl-6-cyclohexylphenol), 2,2'-dimethylene-bis(6-α-methyl-benzyl-p-cresol), 2,2'-ethylidene-bis(4,6-di-tert-butylphenol), phenol), 2,2'-butylidene-bis(4-methyl-6-tert-butylphenol), 4,4'-butylidenebis(3-methyl-6-tert-butylphenol), triethylene glycol-N-bis-3-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionate, 1,6-hexanediol bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], bis[2-tert-butyl-4-methyl-6-(3-tert-butyl-5 -methyl-2-hydroxybenzyl)phenyl]terephthalate, 3,9-bis{2-[3-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionyloxy]-1,1,-dimethylethyl}-2,4,8,10-tetraoxaspiro[5,5]undecane, 4,4'-thiobis(6-tert-butyl-m-cresol), 4,4'-thiobis(3-methyl-6-tert-butylphenol), 2,2'-thiobis(4-methyl-6-tert-butylphenol), bis(3,5-di-tert-butyl-4-hydroxybenzyl)sulfide, 4,4'-di-thiobis(2,6-di-tert-butylphenol), 4,4'-tri-thiobis(2,6-di-tert-butylphenol), 2,2-thiodiethylene bis-[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], 2,4-bis(n-octylthio)-6-(4-hydroxy-3',5'-di-tert-butylanilino)-1,3,5-triazine, N,N'-hexamethylene bis-(3,5-di-tert-butyl-4-hydroxyhydrocinnamide), N,N'-bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl]hydrazine, 1,1,3-tris(2-methyl-4-hydro Examples include 1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene, tris(3,5-di-tert-butyl-4-hydroxyphenyl)isocyanurate, tris(3,5-di-tert-butyl-4-hydroxybenzyl)isocyanurate, 1,3,5-tris(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)isocyanurate, 1,3,5-tris2[3(3,5-di-tert-butyl-4-hydroxyphenyl)propionyloxy]ethyl isocyanurate, and tetrakis[methylene-3-(3',5'-di-tert-butyl-4-hydroxyphenyl)propionate]methane. All of these are easily available. The above hindered phenol stabilizers can be used alone or in combination of two or more.

[0033] The amount of the hindered phenol-based stabilizer to be added is preferably 0.0001 to 1 part by weight, more preferably 0.001 to 0.5 parts by weight, and even more preferably 0.005 to 0.3 parts by weight, per 100 parts by weight of the A component. (III) Other heat stabilizers The resin composition of the present invention may also contain other heat stabilizers than the aromatic phosphite stabilizer and the hindered phenol stabilizer. Suitable examples of such other heat stabilizers include lactone stabilizers, such as the reaction product of 3-hydroxy-5,7-di-tert-butyl-furan-2-one and o-xylene. Details of such stabilizers are described in JP-A-7-233160. Such a compound is commercially available as Irganox HP-136 (trademark, manufactured by CIBA SPECIALTY CHEMICALS), and this compound can be used. Furthermore, stabilizers in which this compound is mixed with various phosphite compounds and hindered phenol compounds are commercially available. Suitable examples include Irganox HP-2921 manufactured by the same company. The amount of lactone stabilizer to be added is preferably 0.0005 to 0.05 parts by weight, more preferably 0.001 to 0.03 parts by weight, based on 100 parts by weight of component A. Examples of other stabilizers include sulfur-containing stabilizers such as pentaerythritol tetrakis(3-mercaptopropionate), pentaerythritol tetrakis(3-laurylthiopropionate), and glycerol-3-stearylthiopropionate. The amount of such sulfur-containing stabilizers to be added is preferably 0.001 to 0.1 parts by weight, more preferably 0.01 to 0.08 parts by weight, per 100 parts by weight of component A. (IV) Ultraviolet absorbers In the resin composition of the present invention, an ultraviolet absorbing agent can be blended for the purpose of imparting light resistance.

[0034] Specific examples of the ultraviolet absorber include benzophenone-based ultraviolet absorbers such as 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-octoxybenzophenone, 2-hydroxy-4-benzyloxybenzophenone, 2-hydroxy-4-methoxy-5-sulfoxybenzophenone, 2,2'-dihydroxy-4-methoxybenzophenone, 2,2',4,4'-tetrahydroxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxy-5-sodium sulfoxybenzophenone, bis(5-benzoyl-4-hydroxy-2-methoxyphenyl)methane, 2-hydroxy-4-n-dodecyloxybenzophenone, and 2-hydroxy-4-methoxy-2'-carboxybenzophenone.

[0035] Benzotriazoles include, for example, 2-(2-hydroxy-5-methylphenyl)benzotriazole, 2-(2-hydroxy-5-tert-octylphenyl)benzotriazole, 2-(2-hydroxy-3,5-dicumylphenyl)phenylbenzotriazole, 2-(2-hydroxy-3-tert-butyl-5-methylphenyl)-5-chlorobenzotriazole, 2,2'-methylenebis[4-(1,1,3,3-tetramethylbutyl)-6-(2H-benzotriazol-2-yl)phenol], 2-(2-hydroxy-3,5-di-tert-butylphenyl)benzotriazole, 2-(2-hydroxy-3,5-di-tert-butylphenyl)-5-chlorobenzotriazole, 2-(2-hydroxy-3,5-di-tert-amylphenyl)benzotriazole, 2-(2-hydroxy-5-tert-octylphenyl)benzotriazole, Examples of the polymer include polymers having a 2-hydroxyphenyl-2H-benzotriazole skeleton, such as azole, 2-(2-hydroxy-5-tert-butylphenyl)benzotriazole, 2-(2-hydroxy-4-octoxyphenyl)benzotriazole, 2,2'-methylenebis(4-cumyl-6-benzotriazolephenyl), 2,2'-p-phenylenebis(1,3-benzoxazin-4-one), and 2-[2-hydroxy-3-(3,4,5,6-tetrahydrophthalimidomethyl)-5-methylphenyl]benzotriazole, as well as copolymers of 2-(2'-hydroxy-5-methacryloxyethylphenyl)-2H-benzotriazole and vinyl monomers copolymerizable with the monomer, and copolymers of 2-(2'-hydroxy-5-acryloxyethylphenyl)-2H-benzotriazole and vinyl monomers copolymerizable with the monomer.

[0036] Examples of hydroxyphenyl triazines include 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-hexyloxyphenol, 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-methyloxyphenol, 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-ethyloxyphenol, 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-propyloxyphenol, and 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-butyloxyphenol.Further examples include compounds in which the phenyl group of the above-mentioned compounds is replaced with a 2,4-dimethylphenyl group, such as 2-(4,6-bis(2,4-dimethylphenyl)-1,3,5-triazin-2-yl)-5-hexyloxyphenol.

[0037] Examples of cyclic imino esters include 2,2'-p-phenylenebis(3,1-benzoxazin-4-one), 2,2'-m-phenylenebis(3,1-benzoxazin-4-one), and 2,2'-p,p'-diphenylenebis(3,1-benzoxazin-4-one).

[0038] Examples of cyanoacrylates include 1,3-bis-[(2'-cyano-3',3'-diphenylacryloyl)oxy]-2,2-bis[(2-cyano-3,3-diphenylacryloyl)oxy]methyl)propane and 1,3-bis-[(2-cyano-3,3-diphenylacryloyl)oxy]benzene.

[0039] Furthermore, the ultraviolet absorber may be a polymer type ultraviolet absorber obtained by copolymerizing such an ultraviolet absorbing monomer and / or a light stable monomer with a monomer such as an alkyl (meth)acrylate by adopting a structure of a radically polymerizable monomer compound. Suitable examples of the ultraviolet absorbing monomer include compounds containing a benzotriazole skeleton, a benzophenone skeleton, a triazine skeleton, a cyclic imino ester skeleton, and a cyanoacrylate skeleton in the ester substituent of a (meth)acrylic acid ester. Among the above, benzotriazole and hydroxyphenyl triazine are preferred in terms of ultraviolet absorbing ability, and cyclic imino ester and cyanoacrylate are preferred in terms of heat resistance and color. Specific examples include "Chemisorb 79" by Chemipro Chemical Co., Ltd. The ultraviolet absorber may be used alone or in a mixture of two or more kinds.

[0040] The content of the ultraviolet absorber is preferably 0.01 to 3 parts by weight, more preferably 0.02 to 2 parts by weight, still more preferably 0.03 to 1 part by weight, and particularly preferably 0.05 to 0.5 parts by weight, based on 100 parts by weight of the A component. (V) Other additives In addition to the above, the resin composition of the present invention may contain small amounts of known additives to impart various functions to the molded product or improve its characteristics, provided that the additives do not impair the object of the present invention. Examples of such additives include antistatic agents, flow modifiers, infrared absorbing agents (heat absorbing agents), and bluing agents. <Method for producing polycarbonate resin composition> In the polycarbonate resin composition of the present invention, the method of blending additives is not particularly limited, and known methods can be used.The most commonly used method is to premix polycarbonate resin and additives, then put them into an extruder to melt-knead, cool the extruded thread, and cut it with a pelletizer to produce a pellet-shaped molding material.

[0041] In the above method, both single-screw extruders and twin-screw extruders can be used as the extruder, but twin-screw extruders are preferred from the viewpoint of productivity and kneading. A representative example of such a twin-screw extruder is TEX (trade name, manufactured by Japan Steel Works, Ltd.). Specific examples of similar types include TEX (trade name, manufactured by Japan Steel Works, Ltd.), TEM (trade name, manufactured by Toshiba Machine Co., Ltd.), KTX (trade name, manufactured by Kobe Steel, Ltd.), and ZSK (trade name, manufactured by Werner & Pfleiderer). As the extruder, one having a vent that can degas the moisture in the raw materials and the volatile gas generated from the melt-kneaded resin is preferably used. A vacuum pump is preferably installed from the vent to efficiently discharge the generated moisture and volatile gas to the outside of the extruder. In addition, a screen for removing foreign matter mixed in the extrusion raw materials can be installed in a zone before the extruder die section, and the foreign matter can be removed from the resin composition. Examples of such screens include wire mesh, screen changers, and sintered metal plates (disc filters, etc.).

[0042] Furthermore, although the additives can be fed independently to the extruder, it is preferable to premix them with the resin raw material as described above. Examples of such premixing means include a Nauta mixer, a V-type blender, a Henschel mixer, a mechanochemical device, and an extrusion mixer. A more suitable method is, for example, to mix a part of the raw resin material with the additives in a high-speed mixer such as a Henschel mixer to prepare a master agent, and then to mix the master agent with the remaining resin raw material in a low-speed mixer such as a Nauta mixer. <Molded products> The aromatic polycarbonate resin composition of the present invention can be molded into desired articles according to known molding methods such as injection molding, blow molding, extrusion molding, and rotational molding.

[0043] Examples of molded articles that can be suitably used in the present invention include molded articles that are to be subjected to steam sterilization treatment for medical or food applications. EXAMPLES

[0044] 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 as long as it does not depart from the gist of the present invention.

[0045] The raw materials used in the following examples and comparative examples are as follows. <(A) Aromatic polycarbonate resin> PC: Teijin Panlite L-1225WP (polycarbonate resin made from bisphenol A, viscosity average molecular weight 22,400) <(B) Epoxy group-containing compound> B-1: NOF Corporation's Marproof G0250SP (copolymer of styrene and glycidyl methacrylate) <(C) Glycerol mono fatty acid ester> C-1: Riken Vitamin Co., Ltd. Rikemal S-100A (glycerin monostearate ester) C-2 (Comparative Example): NOF Corporation Unistar H-476-S (pentaerythritol tetrastearate) <(D) Aromatic phosphite-based heat stabilizer> D-1: BASF IRGAFOS168 (tris(2,4-di-tert-butylphenyl)phosphite) The evaluation methods used in the examples and comparative examples are as follows. (1) Moisture and heat resistance The pellet-shaped molding material obtained from each composition of the examples was dried in a hot air circulation dryer at 120 ° C for 5 hours, and molded into a molded plate with a width of 50 mm, length of 90 mm, and thickness of 2 mm at a molding temperature of 350 ° C and a mold temperature of 80 ° C using an injection molding machine [J85-ELIII manufactured by Japan Steel Works, Ltd.]. This molded plate was subjected to a wet heat treatment (temperature 130 ° C, 24 hours) using a steam sterilizer [SN-510 manufactured by Yamato Scientific Co., Ltd.], and the haze and viscosity average molecular weight (Mv) before and after the wet heat treatment were measured, and the value obtained by subtracting the haze before the wet heat treatment from the haze after the wet heat treatment was calculated as ΔHaze, and the value obtained by subtracting the viscosity average molecular weight (Mv) after the wet heat treatment from the viscosity average molecular weight (Mv) before the wet heat treatment was calculated as ΔMv. The smaller ΔHaze and ΔMv are, the more preferable. The haze of the molded plate was measured according to JIS-K7361-1, and the viscosity average molecular weight (Mv) was measured by the following method.

[0046] Viscosity average molecular weight (Mv) measurement The specific viscosity (η SP ) was measured using an Ostwald viscometer from a solution of 0.7 g of molded plate in 100 ml of methylene chloride at 20°C, and the measured specific viscosity (η SP ) and the viscosity average molecular weight Mv was calculated using the following formula: Specific viscosity (η SP )=(tt 0 ) / t 0 [t 0 is the time it takes for methylene chloride to fall, and t is the time it takes for the sample solution to fall] η SP / c=[η]+0.45×[η] 2 c (where [η] is the intrinsic viscosity) [η]=1.23×10 -4 Mv 0.83 c=0.7 (2) Molding heat resistance ΔE When the test piece was molded in the above (1), the color of the test piece immediately removed from the mold and the color of the test piece removed after being left in the mold for 60 minutes (L * , a * , b * ) and hue (L * ',a * ',b * The color difference ΔE of the test piece was calculated by the following formula (a). The smaller ΔE is, the more preferable.

[0047] ΔE={(ΔL * ) 2 +(Δa * ) 2 +(Δb * ) 2} 1 / 2 ...Formula (a) Color of "Formed plate before retention": L * , a * , b * Color of "Formed plate after retention": L *',a * ',b * ' ΔL * :L * -L * ' Δa * :a * -a * ' Δb * :b * -b * ' [Examples 1 to 4 and Comparative Examples 1 to 6] After blending the raw materials in the ratios shown in Tables 1 and 2, the materials were melt-kneaded at a cylinder temperature of 280°C using a vented twin-screw extruder TEX30α with a screw diameter of 30 mm manufactured by Japan Steel Works, Ltd., and pellet-shaped molding materials were obtained by strand cutting. Test pieces for evaluation were molded under the above conditions, and the above evaluations were performed. The evaluation results are shown in Tables 1 and 2.

[0048] [Table 1]

[0049] [Table 2] [Industrial Applicability]

[0050] The aromatic polycarbonate resin composition of the present invention has excellent resistance to moist heat and molding heat, and therefore can be used in various applications where aromatic polycarbonate resins are used, and is particularly useful for applications such as molded articles that are subjected to steam sterilization in medical and food applications.

Claims

1. An aromatic polycarbonate resin composition comprising 100 parts by weight of (A) an aromatic polycarbonate resin (component A), 0.02 to 0.04 parts by weight of (B) an epoxy group-containing compound (component B), and 0.06 to 0.15 parts by weight of (C) a glycerin monofatty acid ester (component C), said component B being a copolymer of styrene and glycidyl methacrylate.

2. 2. The aromatic polycarbonate resin composition according to claim 1, which contains 0.01 to 0.02 parts by weight of an aromatic phosphite ester-based heat stabilizer (D) (Component D) per 100 parts by weight of Component A.

3. A molded article formed from the aromatic polycarbonate resin composition according to claim 1 or 2.

4. The molded article according to claim 3, which is for medical or food use.

Images