Thermoplastic resin composition and molded article thereof

Abstract

The invention provides a thermoplastic resin composition and a molded article thereof. The thermoplastic resin composition contains 7-64% by mass of a rubber-containing graft copolymer (A), 2-35% by mass of a thermoplastic elastomer (B), 0.5-90% by mass of a polycarbonate resin, a polyacrylic resin or a polybutylene terephthalate resin (C), and 0.5-20% by mass of an inorganic compound (D). The rubber-containing graft copolymer (A) is a graft copolymer obtained by graft polymerizing 20-65 parts by mass of a vinyl monomer mixture (a2) containing an aromatic vinyl monomer and a vinyl cyanide monomer and 35-80 parts by mass of a rubbery polymer (a1). The content of the rubbery polymer (a1) is 2-35% by mass and the difference between the content of the thermoplastic elastomer (B) and the content of the rubbery polymer (a1) is 15% by mass or less per 100% by mass of the total of (A)-(D).

Description

[0001] This application is a divisional application, and the Chinese national application number of the application to which it is directed is 202180006510.8, the application date is April 1, 2021, and the name of the invention is “Thermoplastic resin composition and its molded product”. Technical Field

[0002] The present invention relates to a thermoplastic resin composition having excellent moldability and capable of producing a molded product having no peeling or whitening, excellent appearance, mechanical properties, and weld strength, and having bending properties such that the product does not wrinkle when bent and can maintain the bending properties after repeated operations, is not prone to slipping, and has high gripping properties. The present invention also relates to a molded product obtained by molding the thermoplastic resin composition. Background Art

[0003] Rubber-reinforced aromatic vinyl resins such as ABS resin have a good balance of physical properties between impact resistance and molding processability, and their molded products have excellent appearance. Therefore, they are widely used in OA equipment, home appliances, sundries, building materials, etc.

[0004] Among these, personal computers, OA equipment such as printers, home appliances such as cameras, video recorders, vacuum cleaners, and washing machines that are often used or operated by hand, and automotive interior parts such as door trims and glove boxes that have many opportunities to come into contact with the body of the occupants, are required to maintain the rigidity of the parts and have good cushioning properties, touch, and other tactile properties.

[0005] In order to meet such requirements, sometimes a flexible skin material is joined to a rigid core material and slush-molded to manufacture. However, slush molding has many steps and expensive raw materials, so it is only used for the manufacture of some products (see Patent Document 1).

[0006] It is known that in the rubber part, by mixing a thermoplastic elastomer with a rubber-reinforced aromatic vinyl resin composed of a diene rubber and a silicone rubber or an ethylene-α-olefin rubber, a molded product can be obtained that has excellent mechanical strength and molded product appearance, and has excellent surface touch due to high cushioning properties and soft touch and less stickiness (see Patent Documents 2 and 3). However, a molded product with excellent surface gloss, non-slip and excellent gripping feel cannot be obtained.

[0007] Patent Document 4 proposes a thermoplastic resin molded product that is a molded product having an MIU value of 0.4 or more and is composed of a thermoplastic resin composition containing a specific rubber-reinforced vinyl resin and a thermoplastic elastomer, and has excellent appearance of the molded product such as mechanical strength and surface gloss, and has a tactile feel that is not easy to slide and has an excellent grip. However, the performance of the thermoplastic resin molded product, such as repeated bending, is insufficient, and further improvement is desired in the strength of the housing as the molded product.

[0008] Patent Document 1: Japanese Patent Application Publication No. 2013-159122

[0009] Patent Document 2: Japanese Patent Application Publication No. 2016-199729

[0010] Patent Document 3: Japanese Patent Application Publication No. 2017-8227

[0011] Patent Document 4: Japanese Patent Application Publication No. 2019-73645 Summary of the invention

[0012] An object of the present invention is to provide a thermoplastic resin composition and a molded article thereof, wherein the thermoplastic resin composition has excellent moldability and can realize the following molded article: the molded article has no peeling or whitening, can obtain excellent appearance, mechanical properties, and weld strength of the molded article, and as for bending performance, does not wrinkle when bent, and can maintain the bending performance based on repeated operations, is not easy to slip, and has high grip performance.

[0013] The present inventors have found that the above object can be achieved by using a thermoplastic resin composition comprising a rubber-containing graft copolymer (A), a thermoplastic elastomer (B), another thermoplastic resin (C) and an inorganic compound (D) in specific proportions.

[0014] The gist of the present invention is as follows.

[0015] [1] A thermoplastic resin composition comprising 7 to 64% by mass of a rubber-containing graft copolymer (A), 2 to 35% by mass of a thermoplastic elastomer (B), 0.5 to 90% by mass of another thermoplastic resin (C), and 0.5 to 20% by mass of an inorganic compound (D) (wherein the total of (A), (B), (C), and (D) (hereinafter referred to as "the total of components (A) to (D)") is 100% by mass), characterized in that:

[0016] The rubber-containing graft copolymer (A) is a graft copolymer obtained by graft-polymerizing 20 to 65 parts by mass of a vinyl monomer mixture (a2) containing an aromatic vinyl monomer and a cyanide vinyl monomer with 35 to 80 parts by mass of a rubber polymer (a1) (the total amount of the rubber polymer (a1) and the vinyl monomer mixture (a2) is 100 parts by mass).

[0017] The content of the rubber polymer (a1) is 2 to 35% by mass in 100% by mass of the total of the components (A) to (D).

[0018] In 100% by mass of the total of the components (A) to (D), the difference between the content (% by mass) of the rubber polymer (a1) and the content (% by mass) of the thermoplastic elastomer (B) is within 15% by mass.

[0019] [2] The thermoplastic resin composition according to claim 1, wherein the other thermoplastic resin (C) is at least one selected from acrylonitrile-styrene resins, polycarbonate resins, polyacrylic acid resins and polybutylene terephthalate resins.

[0020] [3] A thermoplastic resin composition as described in [1] or [2], wherein the volume average particle size of the rubber polymer (a1) is 100 to 1500 nm, the ratio of the aromatic vinyl monomer to the cyanide vinyl monomer in 100% by mass of the vinyl monomer mixture (a2) is aromatic vinyl monomer / cyanide vinyl monomer=50 to 95% by mass / 50 to 5% by mass, and the grafting rate of the rubber-containing graft copolymer (A) is 20 to 100% by mass.

[0021] [4] The thermoplastic resin composition according to any one of [1] to [3], wherein the thermoplastic elastomer (B) has an MFR (200°C, 49.0 N) of 1 to 25 g / 10 min and an MFR (230°C, 21.2 N) of 3 to 30 g / 10 min.

[0022] [5] A thermoplastic resin composition as described in any one of [1] to [4], wherein the thermoplastic elastomer (B) is a styrene-based elastomer, which is a block copolymer and / or a hydrogenated product thereof containing one or more polymer blocks P of an aromatic vinyl compound and one or more polymer blocks Q of a conjugated diene compound, respectively, and has a mass average molecular weight of 10,000 to 800,000, a polymer block P content of 5 to 60% by mass, and a polymer block Q content of 95 to 40% by mass.

[0023] [6] The thermoplastic resin composition according to any one of [1] to [5], wherein the inorganic compound (D) is muscovite.

[0024] [7] A thermoplastic resin molded article obtained by molding the thermoplastic resin composition according to any one of [1] to [6].

[0025] Effects of the Invention

[0026] According to the thermoplastic resin composition of the present invention, a thermoplastic resin composition and a molded product thereof can be provided. The composition has excellent moldability and can realize the following molded products: the molded product has no peeling or whitening, and can obtain excellent appearance, mechanical properties, and weld strength of the molded product. In addition, as for bending performance, it does not wrinkle when bent, and can maintain the bending performance based on repeated operations, is not easy to slide, and has high grip performance. DETAILED DESCRIPTION

[0027] The embodiments of the present invention are described in detail below.

[0028] In this specification, the "molded article" means an article obtained by molding the thermoplastic resin composition.

[0029] "Unit" means a structural part derived from a monomer compound (monomer) before polymerization and introduced into a polymer or copolymer. For example, "aromatic vinyl monomer unit" means "a structural part derived from an aromatic vinyl monomer and introduced into a polymer or copolymer".

[0030] “(Meth)acrylic acid” means one or both of “acrylic acid” and “methacrylic acid”.

[0031] [Thermoplastic resin composition]

[0032] The thermoplastic resin composition of the present invention is a thermoplastic resin composition comprising a rubber-containing graft copolymer (A) (hereinafter sometimes referred to as "component (A)"), a thermoplastic elastomer (B) (hereinafter sometimes referred to as "component (B)"), a thermoplastic resin (C) other than the rubber-containing graft copolymer (A) and the thermoplastic elastomer (B) (hereinafter sometimes referred to as "component (C)"), and an inorganic compound (D) (hereinafter sometimes referred to as "component (D)") in specific proportions.

[0033] [Rubber-containing graft copolymer (A)]

[0034] The rubber-containing graft copolymer (A) is obtained by graft-polymerizing the vinyl monomer mixture (a2) in the presence of the rubber polymer (a1).

[0035] <Rubbery Polymer (a1)>

[0036] The rubber polymer (a1) (hereinafter sometimes referred to as "component (a1)") constituting the rubber-containing graft copolymer (A) is not particularly limited, and examples thereof include diene rubber, acrylic rubber, and ethylene rubber.

[0037] Specifically, polybutadiene, poly(butadiene-styrene), poly(butadiene-acrylonitrile), polyisoprene, poly(butadiene-butyl acrylate), poly(butadiene-methyl acrylate), poly(butadiene-methyl methacrylate), poly(butadiene-ethyl acrylate), ethylene-propylene rubber, ethylene-propylene-diene rubber, poly(ethylene-isobutylene), poly(ethylene-methyl acrylate), poly(ethylene-ethyl acrylate), and the like can be cited.

[0038] These rubber polymers may be used alone or in combination of two or more.

[0039] Among them, polybutadiene and styrene-butadiene copolymer rubber are particularly preferably used from the viewpoint of improving impact resistance.

[0040] The volume average particle size of the rubber polymer (a1) is preferably 100 to 1500 nm, more preferably 150 to 1000 nm, and even more preferably 200 to 500 nm, from the viewpoint of impact resistance, moldability, flowability and appearance of the obtained thermoplastic resin composition.

[0041] The volume average particle size of the rubber polymer (a1) is a value measured by the method described in the section of Examples described later.

[0042] <Vinyl Monomer Mixture (a2)>

[0043] The vinyl monomer mixture (a2) (hereinafter sometimes referred to as "component (a2)") is a vinyl monomer mixture containing at least an aromatic vinyl monomer and a cyanide vinyl monomer.

[0044] Examples of the aromatic vinyl monomer include styrene, α-methylstyrene, p-methylstyrene, vinyltoluene, tert-butylstyrene, o-ethylstyrene, o-chlorostyrene, and o-,p-dichlorostyrene.

[0045] These monomers may be used alone or in combination of two or more.

[0046] Examples of the vinyl cyanide monomer include acrylonitrile, methacrylonitrile, ethacrylonitrile, etc. Acrylonitrile is particularly preferred.

[0047] The vinyl cyanide monomer may be used alone or in combination of two or more.

[0048] From the viewpoint of moldability and appearance of molded articles, the ratio of the aromatic vinyl monomer to the cyanide vinyl monomer in 100% by mass of the vinyl monomer mixture (a2) is preferably aromatic vinyl monomer / cyanide vinyl monomer=50 to 95% by mass / 50 to 5% by mass, more preferably 60 to 85% by mass / 40 to 15% by mass, and still more preferably 65 to 80% by mass / 35 to 20% by mass.

[0049] In the vinyl monomer mixture (a2), in addition to aromatic vinyl monomers and cyanide vinyl monomers, other vinyl monomers that can copolymerize with them can also be included in the range of 0 to 30% by mass. As other vinyl monomers that can copolymerize with them, unsaturated carboxylic acid ester monomers such as (meth) methyl acrylate, maleimide compounds such as N-methylmaleimide, N-cyclohexylmaleimide, N-phenylmaleimide, unsaturated dicarboxylic acids such as maleic acid, unsaturated dicarboxylic anhydrides such as maleic anhydride, unsaturated amides such as acrylamide, etc., can be cited. One or more of the above, but it is not limited to these. Among them, methyl (meth) acrylate, N-phenylmaleimide, and maleic anhydride are preferred.

[0050] <Ratio of Rubber Polymer (a1) and Vinyl Monomer Mixture (a2)>

[0051] The rubber-containing graft copolymer (A) is obtained by graft polymerization of 20 to 65% by mass of a vinyl monomer mixture (a2) in the presence of 35 to 80% by mass of a rubber polymer (a1), wherein the total amount of the rubber polymer (a1) and the vinyl monomer mixture (a2) is 100% by mass.

[0052] When the rubber polymer (a1) is less than 35% by mass and the vinyl monomer mixture (a2) is greater than 65% by mass, the weld strength and wrinkling properties are poor. When the rubber polymer (a1) is greater than 80% by mass and the vinyl monomer mixture (a2) is less than 20% by mass, the moldability and thermal stability during molding are reduced. The proportion of the rubber polymer (a1) is preferably 45 to 78% by mass, more preferably 53 to 73% by mass. The proportion of the vinyl monomer mixture (a2) is preferably 22 to 55% by mass, more preferably 27 to 47% by mass.

[0053] In the rubber-containing graft copolymer (A), it is not necessary to graft the total amount of the vinyl monomer mixture (a2), and a mixture with an ungrafted copolymer is usually used. This mixture is originally a composition, but is included in the rubber-containing graft copolymer (A) in the present invention.

[0054] The graft ratio of the rubber-containing graft copolymer (A) is not limited, but is preferably 20 to 100% by mass, more preferably 30 to 80% by mass, and even more preferably 40 to 70% by mass from the viewpoint of impact resistance.

[0055] The graft ratio of the rubber-containing graft copolymer (A) is measured by the method described in the section of Examples described later.

[0056] The method for graft polymerization of the rubber-containing graft copolymer (A) is not particularly limited, and the rubber-containing graft copolymer (A) can be produced by any method such as a known emulsion polymerization method, a suspension polymerization method, a continuous bulk polymerization method, a continuous solution polymerization method, etc. The rubber-containing graft copolymer (A) is preferably produced by an emulsion polymerization method or a bulk polymerization method. From the perspective of easily adjusting the emulsifier content and the water content in the rubber-containing graft copolymer (A), the rubber-containing graft copolymer (A) is most preferably produced by an emulsion polymerization method.

[0057] In the thermoplastic resin composition of the present invention, the content of component (A) is 7 to 64 mass %, preferably 10 to 55 mass %, and more preferably 15 to 52 mass % in the total 100 mass % of components (A) to (D). When the content of component (A) is above the above lower limit, the weld strength and weld retention rate are good. When the content of component (A) is below the above upper limit, the moldability is good.

[0058] In 100% by mass of the thermoplastic resin composition of the present invention, the content of the rubber polymer (a1) is 2 to 35% by mass, preferably 5 to 35% by mass, and more preferably 8 to 33% by mass. When the content of the rubber polymer (a1) is above the lower limit, the touch (grip), non-slip properties, and weld strength are good. When the content of the rubber polymer (a1) is below the upper limit, the moldability is good.

[0059] [Thermoplastic elastomer (B)]

[0060] The thermoplastic elastomer (B) used in the present invention is not particularly limited as long as it is a polymer that can provide a molded product having rubber elasticity by heating and melting. The thermoplastic elastomer (B) can be molded by heating and melting, but the diene rubber and non-diene rubber used in the above-mentioned component (a1) cannot be molded by heating and melting, and the two are different in this point.

[0061] The MFR (200° C., 49.0 N) of the thermoplastic elastomer (B) is preferably 1 to 25 g / 10 min, more preferably 2 to 15 g / 10 min.

[0062] The MFR (230° C., 21.2 N) of the thermoplastic elastomer (B) is preferably 3 to 30 g / 10 min, more preferably 5 to 20 g / 10 min.

[0063] Specific examples of the thermoplastic elastomer (B) include diene elastomers such as styrene elastomers and polybutadiene elastomers, olefin elastomers, polyurethane elastomers, polyvinyl chloride elastomers, ester elastomers, fluororesin elastomers, ionomers, etc. These thermoplastic elastomers may be used alone or in combination of two or more.

[0064] Among them, diene elastomers such as styrene elastomers and polybutadiene elastomers are suitable from the viewpoints of tactile feeling (gripping feeling) and low slip resistance.

[0065] Specific examples of styrene-based elastomers include block copolymers each containing one or more polymer blocks P of an aromatic vinyl compound and one or more polymer blocks Q of a conjugated diene compound, and hydrogenated products thereof. The polymer blocks P and Q may be linearly bonded or radially bonded.

[0066] The polymer block Q may be a random copolymer containing a small amount of an aromatic vinyl compound as a structural unit, or may be a so-called tapered block in which the content of the structural unit derived from the aromatic vinyl compound gradually increases.

[0067] The structure of the block copolymer is not particularly limited, and any of the (PQ)n type, (PQ)nA type, and (PQ)nC type can be used.

[0068] In the formula, P represents a polymer block of an aromatic vinyl compound, Q represents a polymer block of a conjugated diene compound, C represents a coupling agent residue, and n represents an integer greater than 1.

[0069] As the aromatic vinyl compound constituting the polymer block P of the styrene-based elastomer, all of the aromatic vinyl compounds listed as the vinyl-based monomer of the above-mentioned component (a2) can be used, but styrene is preferably used.

[0070] These aromatic vinyl compounds may be used alone or in combination of two or more.

[0071] Examples of the conjugated diene compound constituting the structural unit of the polymer block Q of the styrene-based elastomer include 1,3-butadiene, isoprene, 2-methyl-1,3-butadiene, 2,3-diethyl-butadiene, 2-neopentyl-1,3-butadiene, 2-chloro-1,3-butadiene, 2-cyano-1,3-butadiene, substituted straight-chain conjugated pentadienes, straight-chain and side-chain conjugated hexadiene, etc. Among these, 1,3-butadiene, isoprene and 2-methyl-1,3-butadiene are preferred.

[0072] These conjugated diene compounds can be used alone or in combination of two or more.

[0073] The content of the polymer block P of the styrene elastomer is preferably 5 to 60% by mass, more preferably 15 to 50% by mass. The content of the polymer block Q of the styrene elastomer is preferably 95 to 40% by mass, more preferably 85 to 50% by mass. When the content of the polymer blocks P and Q is within the above range, the touch (grip) and the non-slip property are good.

[0074] The styrene elastomer composed of the above-mentioned block copolymer as a non-hydrogenated product can be manufactured by block copolymerization according to a conventional method. The hydrogenated product of the block copolymer can be obtained by hydrogenating the polymer block Q of the conjugated diene compound of the block copolymer thus obtained using a known method. As a specific method, there are Japanese Patent Publication No. 42-8704, Japanese Patent Publication No. 43-6636, Japanese Patent Publication No. 63-4841, Japanese Patent Publication No. 63-5401, Japanese Patent Publication No. 2-133406, and Japanese Patent Publication No. 1-297413.

[0075] In the hydrogenation reaction, in the case of a conjugated diene polymer in which the polymer block Q is a polymer block of 1,3-butadiene, when non-selective hydrogenation is performed, ethylene is generated from the portion polymerized with a 1,4-vinyl bond, butene is generated from the portion polymerized with a 1,2-vinyl bond, and styrene-ethylene-butylene-styrene copolymer (SEBS) and the like are generated as hydrogenates. When the 1,2-vinyl bond is selectively hydrogenated, styrene-butadiene-butylene-styrene copolymer (SBBS) and the like are generated as hydrogenates.

[0076] Preferred specific examples of the above-mentioned styrene-based elastomers include styrene-butadiene-styrene block copolymers (SBS), styrene-ethylene-butylene-styrene copolymers (SEBS), styrene-butadiene-butylene-styrene copolymers (SBBS), styrene-isoprene-styrene copolymers (SIS), etc. Among them, styrene-ethylene-butylene-styrene copolymers (SEBS) are particularly suitable from the aspects of tactile feel (grip feeling) and non-slip properties.

[0077] Commercially available SEBS may be used. Commercially available SEBS include Dynaron series (trade name, manufactured by JSR Corporation), Lavalon series (trade name, manufactured by Mitsubishi Chemical Corporation), Tuftec series (trade name, manufactured by Asahi Kasei Corporation), and TPE-SB series (trade name, manufactured by Sumitomo Chemical Industries, Ltd.).

[0078] As thermoplastic elastomers (B) other than styrene-based elastomers, for example, high cis-butadiene rubber (BR) and low cis-butadiene rubber (BR), high cis-isoprene rubber (IR), emulsion polymerization and solution polymerization styrene-butadiene rubber (SBR), nitrile rubber (NBR), ethylene-propylene rubber (EPM, EPDM), chloroprene rubber, butyl rubber, natural rubber (NR), etc.

[0079] The thermoplastic elastomer (B) such as a styrene-based elastomer may be used alone or in combination of two or more components different in the type, structure or structural unit, physical properties, etc. of the elastomer.

[0080] In the thermoplastic resin composition of the present invention, the content of component (B) is 2 to 35% by mass, preferably 5 to 34% by mass, and more preferably 8 to 33% by mass in a total of 100% by mass of components (A) to (D). When the content of component (B) is above the lower limit, weld strength, weld retention, tactile feel (gripability), and non-slip properties are good. When the content of component (B) is below the upper limit, moldability and appearance of molded products are good.

[0081] In the thermoplastic resin composition of the present invention, the difference between the content (mass %) of component (a1) and the content (mass %) of component (B) in the total of 100 mass % of components (A) to (D) (hereinafter sometimes referred to as "(a1)-(B)") is within 15 mass % in absolute value. When (a1)-(B) is within 15 mass %, the appearance, wrinkling resistance, wrinkling resistance in repeated operation, and weld strength of the molded article are good. (a1)-(B) is preferably within 10 mass %, more preferably within 8.0 mass %, further preferably within 6.0 mass %, particularly preferably within 5 mass %, particularly preferably within 3.5 mass %, and most preferably 0 to 2.0 mass %.

[0082] When the amount of (a1)-(B) is within 15 mass %, either component (a1) or component (B) may be greater.

[0083] [Other thermoplastic resins (C)]

[0084] The other thermoplastic resin (C) contained in the thermoplastic resin composition of the present invention may be any thermoplastic resin other than the component (A) and the component (B), and examples thereof include acrylonitrile-styrene resins, polycarbonate resins, polyacrylic acid resins, polybutylene terephthalate resins, vinyl chloride resins, polyamide resins, polyethylene resins, polybutene resins, and polyoxymethylene resins.

[0085] In the thermoplastic resin composition of the present invention, the other thermoplastic resin (C) is preferably an acrylonitrile-styrene resin, a polycarbonate resin, a polyacrylic acid resin, or a polybutylene terephthalate resin, particularly because of its adhesion to the housing resin of OA equipment or the like, or because it is expected to be used as a resin for the housing itself and because it is easy to obtain a balance of physical properties.

[0086] The thermoplastic resin (C) can be used alone or in combination of two or more.

[0087] In the thermoplastic resin composition of the present invention, the content of component (C) is 0.5 to 90% by mass, preferably 2 to 83% by mass, and more preferably 4 to 74% by mass in the total 100% by mass of components (A) to (D). When the content of component (C) is above the above lower limit, the moldability is excellent. When the content of component (C) is below the above upper limit, the weld strength and weld retention rate are excellent.

[0088] <Acrylonitrile-styrene resin>

[0089] The acrylonitrile-styrene resin is a copolymer containing structural parts derived from an aromatic vinyl monomer and a cyanide vinyl monomer.

[0090] As the aromatic vinyl monomer, styrene, α-methylstyrene, p-methylstyrene, vinyltoluene, tert-butylstyrene, o-ethylstyrene, o-chlorostyrene, o-, p-dichlorostyrene can be mentioned. These monomers can be used alone or in combination of two or more.

[0091] Examples of the vinyl cyanide monomer include acrylonitrile, methacrylonitrile, and ethacrylonitrile, and acrylonitrile is particularly preferred. The vinyl cyanide monomer may be used alone or in combination of two or more.

[0092] From the viewpoint of moldability and appearance of molded articles, the ratio of the aromatic vinyl monomer unit to the vinyl cyanide monomer unit in 100% by mass of the acrylonitrile-styrene resin is preferably aromatic vinyl monomer unit / vinyl cyanide monomer unit=50 to 95% by mass / 50 to 5% by mass, more preferably 60 to 85% by mass / 40 to 15% by mass, and still more preferably 65 to 80% by mass / 35 to 20% by mass.

[0093] In the acrylonitrile-styrene resin, in addition to aromatic vinyl monomers and cyanide vinyl monomers, other vinyl monomer units that can copolymerize with them can also be included in the range of 0 to 30 mass%. As other vinyl monomers that can copolymerize with them, unsaturated carboxylic acid ester monomers such as (meth) methyl acrylate, maleimide compounds such as N-methylmaleimide, N-cyclohexylmaleimide, N-phenylmaleimide, unsaturated dicarboxylic acids such as maleic acid, unsaturated dicarboxylic anhydrides such as maleic anhydride, or unsaturated amides such as acrylamide, etc., can be cited. One or more of the above, but it is not limited to these. Among them, methyl (meth) acrylate, N-phenylmaleimide, and maleic anhydride are preferred.

[0094] The mass average molecular weight (Mw) of the acrylonitrile-styrene resin is preferably 50,000 to 400,000, more preferably 70,000 to 350,000, and even more preferably 90,000 to 300,000.

[0095] The molecular weight distribution (Mw / Mn) of the acrylonitrile-styrene resin is preferably 1.3 to 2.8, more preferably 1.8 to 2.6, and even more preferably 1.9 to 2.4.

[0096] The mass average molecular weight and molecular weight distribution of the acrylonitrile-styrene resin can be measured as polystyrene-equivalent values ​​based on GPC.

[0097] The acrylonitrile-styrene resin may be used alone or in combination of two or more acrylonitrile-styrene resins having different monomer compositions, molecular weights, etc.

[0098] <Polycarbonate resin>

[0099] The polycarbonate resin is a polymer having a basic structure of a carbonate bond represented by the general formula -(-OROC(=O)-)-.

[0100] As the polycarbonate resin, an aromatic polycarbonate resin in which the carbon atom directly bonded to the carbonic acid bond in its basic structure is an aromatic carbon atom is preferably used. In this case, in the formula, R is usually an aromatic hydrocarbon group, and in order to impart various properties, it can also be an aromatic hydrocarbon group into which a heteroatom or a hetero bond is introduced.

[0101] Representative examples of the aromatic polycarbonate resin include those produced from dihydroxyaryl compounds such as 2,2-bis(4-hydroxyphenyl)propane (bisphenol A).

[0102] Examples of the dihydroxydiaryl compound include, in addition to bisphenol A, bis(4-hydroxyphenyl)methane, 1,1-bis(4-hydroxyphenyl)ethane, 2,2-bis(4-hydroxyphenyl)butane, 2,2-bis(4-hydroxyphenyl)octane, bis(4-hydroxyphenyl)diphenylmethane, 2,2-bis(4-hydroxy-3-methylphenyl)propane, 1,1-bis(4-hydroxy-3-tert-butylphenyl)propane, 2,2-bis(4-hydroxy-3-bromophenyl)propane, 2,2-bis(4-hydroxy-3,5-dibromophenyl)propane, and 2,2-bis(4-hydroxy-3,5-dichlorophenyl)propane. Alkanes; bis(hydroxyaryl)cycloalkanes such as 1,1-bis(4-hydroxyphenyl)cyclopentane and 1,1-bis(4-hydroxyphenyl)cyclohexane; dihydroxydiaryl ethers such as 4,4'-dihydroxydiphenyl ether and 4,4'-dihydroxy-3,3'-dimethyldiphenyl ether; dihydroxydiaryl sulfides such as 4,4'-dihydroxydiphenyl sulfide and 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfide; dihydroxydiaryl sulfoxides such as 4,4'-dihydroxydiphenyl sulfoxide; dihydroxydiaryl sulfones such as 4,4'-dihydroxydiphenyl sulfone and 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfone, etc.

[0103] These components may be used alone or in combination of two or more. In addition to these, piperazine, dipiperidylhydroquinone, resorcinol, 4,4'-dihydroxydiphenyl and the like may also be used in combination.

[0104] The above-mentioned dihydroxydiaryl compound can be used in a mixture with the following trivalent or higher phenolic compounds. Examples of the trivalent or higher phenolic compounds include pyrogallol, 4,6-dimethyl-2,4,6-tris-(4-hydroxyphenyl)-heptene, 2,4,6-trimethyl-2,4,6-tris-(4-hydroxyphenyl)-heptane, 1,3,5-tris-(4-hydroxyphenyl)-benzene, 1,1,1-tris-(4-hydroxyphenyl)-ethane, and 2,2-bis-(4,4-bis(4-hydroxyphenyl)cyclohexyl)-propane.

[0105] There is no particular limitation on the viscosity average molecular weight (Mv) of polycarbonate resins such as aromatic polycarbonate resins, and materials of 15,000 to 40,000 can be appropriately used. When the viscosity average molecular weight (Mv) is less than 15,000, there is a tendency for impact resistance and heat resistance to deteriorate. When the viscosity average molecular weight (Mv) is greater than 40,000, there is a tendency for poor fluidity and poor moldability. The viscosity average molecular weight (Mv) of the polycarbonate resin is more preferably 16,000 to 35,000, and even more preferably 18,000 to 30,000.

[0106] Therefore, for example, when producing an aromatic polycarbonate resin, it is preferred to use the above-mentioned dihydroxydiaryl compound and, if necessary, a molecular weight modifier, a catalyst, etc. to produce an aromatic polycarbonate resin having such a viscosity average molecular weight.

[0107] The viscosity average molecular weight [Mv] of the polycarbonate resin is a value obtained by using methylene chloride as a solvent and using an Ubbelohde viscometer to determine the intrinsic viscosity [η] (unit: dl / g) at a temperature of 20°C, and calculating the viscosity average molecular weight according to Schnell's viscosity formula, that is, η=1.23×10-4Mv0.83. The intrinsic viscosity [η] is a value calculated by measuring the specific viscosity [ηsp] at each solution concentration [C] (g / dl) and using the following formula.

[0108] [Number 1]

[0109]

[0110] Specific examples of the aromatic polycarbonate resin include commercially available products such as “Iupilon series” and “NOVAREX series” manufactured by Mitsubishi Engineering-Plastics Corporation and “TARFLON series” manufactured by Idemitsu Kosan Co., Ltd.

[0111] The polycarbonate resins such as aromatic polycarbonate resins may be used alone or in combination of two or more polycarbonate resins having different monomer compositions, physical properties, etc. For example, two or more polycarbonate resins having different viscosity average molecular weights may be mixed and adjusted to the above-mentioned appropriate viscosity average molecular weight for use.

[0112] <Polyacrylic acid resin>

[0113] The polyacrylic resin is obtained by polymerizing a vinyl monomer or a vinyl monomer mixture containing a (meth)acrylate monomer using a known method. The vinyl monomer mixture contains a (meth)acrylate monomer as an essential component and may contain other vinyl monomers as shown below in a range of 40% by mass or less as required.

[0114] Examples of the (meth)acrylate monomer include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, and phenyl (meth)acrylate.

[0115] As other vinyl monomers other than (meth)acrylate monomers, for example, aromatic vinyl monomers, cyanide vinyl monomers, maleimide monomers, (meth)acrylic acid, etc. Aromatic vinyl monomers and cyanide vinyl monomers can be the same as those contained in the vinyl monomer mixture (a2).

[0116] Examples of maleimide monomers include N-alkylmaleimides (N-methylmaleimide, N-ethylmaleimide, N-n-propylmaleimide, N-isopropylmaleimide, N-n-butylmaleimide, N-isobutylmaleimide, N-tert-butylmaleimide, etc.), N-cycloalkylmaleimide (N-cyclohexylmaleimide, etc.), and N-arylmaleimide (N-phenylmaleimide, N-alkyl-substituted phenylmaleimide, N-chlorophenylmaleimide, etc.).

[0117] Specific examples of the copolymer resin of methyl methacrylate and methyl acrylate among polyacrylic resins include commercially available products such as "Parapet G" manufactured by KURARAY, and "ACRYPET VH" and "ACRYPET MD" manufactured by Mitsubishi Chemical Corporation.

[0118] Specific examples of the polyacrylic acid-based resin containing both a (meth)acrylate monomer unit and a maleimide monomer unit include commercially available products such as "Parapet SH-N" manufactured by KURARAY Co., Ltd. and "Polyimilex PML203" manufactured by Nippon Shokubai Co., Ltd.

[0119] The polyacrylic acid-based resins may be used alone or in combination of two or more.

[0120] <Polybutylene terephthalate resin>

[0121] Polybutylene terephthalate resins are generally obtained by polycondensation of terephthalic acid and / or its derivatives with 1,4-butanediol and / or its derivatives. As polybutylene terephthalate resins, those obtained by copolymerization of other copolymerizable dicarboxylic acids and / or their derivatives or diols, etc., may also be used within the scope that does not impair the purpose of the present invention.

[0122] Examples of copolymerizable dicarboxylic acids include isophthalic acid, 2-chloroterephthalic acid, 2,5-dichloroterephthalic acid, 2-methylterephthalic acid, 4,4-stilbene dicarboxylic acid, 4,4-biphenyl dicarboxylic acid, phthalic acid, 2,6-naphthalene dicarboxylic acid, dibenzoic acid, bis(p-carboxyphenyl)methane, anthracene dicarboxylic acid, 4,4-diphenyl ether dicarboxylic acid, 4,4-diphenoxyethane dicarboxylic acid, adipic acid, sebacic acid, azelaic acid, dodecanedioic acid, 1,3-cyclohexane dicarboxylic acid, and 1,4-cyclohexane dicarboxylic acid, or their derivatives. These copolymerizable dicarboxylic acids and / or their derivatives may be used alone or in combination of two or more selected from the exemplified components.

[0123] Examples of copolymerizable diols include ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 2,2-dimethyl-1,3-propylene glycol, trans-2,2,4,4-tetramethyl-1,3-cyclobutanediol or cis-2,2,4,4-tetramethyl-1,3-cyclobutanediol, neopentyl glycol, 1,5-pentanediol, 1,6-hexanediol, 1,4-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, decanediol, cyclohexanediol, p-xylene glycol, bisphenol A, tetrabromobisphenol A, tetrabromobisphenol A-bis(2-hydroxyethyl ether), etc. These copolymerizable diols may be used alone or in combination of two or more thereof, for example, as components appropriately selected from the exemplified substances.

[0124] The polybutylene terephthalate resin preferably has an intrinsic viscosity of 0.7 to 1.50 dl / g in order to sufficiently ensure the fluidity and moldability of the thermoplastic resin composition of the present invention and sufficiently ensure the impact resistance of the thermoplastic resin molded article of the present invention molded using the thermoplastic resin composition.

[0125] The intrinsic viscosity of the polybutylene terephthalate-based resin was measured at 30° C. in a mixed solution of tetrachloroethane and phenol at a ratio of 1:1 (mass ratio).

[0126] Specific examples of the polybutylene terephthalate-based resin include commercially available products such as "NOVADURAN" from Mitsubishi Engineering-Plastics Co., Ltd. and "Duranex" from Polyplastics Co., Ltd.

[0127] The polybutylene terephthalate-based resin may be used alone or in combination of two or more.

[0128] [Inorganic compounds (D)]

[0129] The thermoplastic resin composition of the present invention can improve moldability and stabilize the form of the product by containing the inorganic compound (D).

[0130] Examples of the inorganic compound (D) include metal fibers, aramid fibers, asbestos, potassium titanate whiskers, wollastonite, glass flakes, glass beads, talc, mica, clay, calcium carbonate, barium sulfate, titanium oxide, and aluminum oxide.

[0131] The inorganic compound (D) is preferably in a flat plate, a linear shape, or a scaly shape, and more preferably in a plate or a scaly shape from the viewpoints of appearance, wrinkle resistance during bending, and bending properties during repeated operation.

[0132] The volume average particle size (MV) of the inorganic compound (D) determined by laser diffraction is preferably 1 to 200 μm, more preferably 2 to 120 μm, further preferably 10 to 80 μm, particularly preferably 15 to 40 μm.

[0133] When the volume average particle size (MV) of the inorganic compound (D) is greater than the above lower limit, the weld strength, weld retention rate, bending wrinkling resistance, and bending property in repeated operations are good. When the volume average particle size (MV) of the inorganic compound (D) is less than the above upper limit, the moldability, molded product appearance, and weld retention rate are good.

[0134] The ratio of the volume average particle size (MV) to the thickness (aspect ratio) of the inorganic compound (D) is preferably 5-150, more preferably 10-120, and even more preferably 40-90.

[0135] This is because when the aspect ratio is above the lower limit, the balance between moldability, bending wrinkling resistance, and bending resistance during repeated operation is good. When the aspect ratio is below the upper limit, the appearance of the molded product, weld strength, weld retention rate, touch (gripability), and non-slip properties are good.

[0136] As the inorganic compound (D), only one of them may be used or two or more thereof may be mixed and used. Among them, titanium oxide, talc, mica and calcium carbonate are preferred, and mica is particularly preferred for reasons of appearance, bending wrinkling resistance and bending property in repeated operations.

[0137] Mica includes dry-crushed mica and wet-crushed mica. Wet-crushed mica is preferred, and wet-crushed muscovite is particularly preferred. Compared with dry-crushed mica, wet-crushed mica has a higher purity and does not affect the appearance, so it has a high utilization value.

[0138] In the thermoplastic resin composition of the present invention, the content of component (D) is 0.5 to 20% by mass, preferably 2 to 18% by mass, and more preferably 3 to 15% by mass in a total of 100% by mass of components (A) to (D). When the content of component (D) is above the above lower limit, the above effect brought about by using component (D) can be fully obtained. When the content of component (D) is below the above upper limit, mechanical properties, appearance of molded products, etc. are not impaired.

[0139] [Other additives]

[0140] The thermoplastic resin composition of the present invention may contain various additives in order to improve the performance as a molding resin within the range not impairing the object of the present invention.

[0141] For example, various stabilizers such as hindered phenol-based, sulfur-containing organic compound-based, phosphorus-containing organic compound-based antioxidants, phenol-based, acrylate-based heat stabilizers, ester exchange inhibitors such as a mixture of monostearyl acid phosphate and distearyl acid phosphate, benzotriazole-based, benzophenone-based, salicylate-based ultraviolet absorbers, organic nickel-based, hindered amine-based light stabilizers, etc. can be added as needed; lubricants such as metal salts of higher fatty acids and higher fatty amides; plasticizers such as phthalates and phosphates; halogen-containing compounds such as polybrominated diphenyl ethers, tetrabromobisphenol-A, brominated epoxy oligomers, brominated polycarbonate oligomers, phosphorus compounds, flame retardants / flame retardant additives such as antimony trioxide; carbon black, pigments and dyes, etc.

[0142] [Method for producing thermoplastic resin composition]

[0143] The thermoplastic resin composition of the present invention can be produced by various methods such as melt-kneading the above components (A) to (D) and the above additives used as necessary using a Banbury mixer, a roll, a single-screw extruder or a multi-screw extruder.

[0144] [Thermoplastic resin molded products]

[0145] The thermoplastic resin molded article of the present invention is obtained by molding the thermoplastic resin composition of the present invention by a known molding method.

[0146] Examples of the molding method include injection molding, compression molding, extrusion molding, vacuum molding, and blow molding.

[0147] The thermoplastic resin molded article of the present invention obtained by molding the thermoplastic resin composition of the present invention does not peel or whiten during the molding process, and can obtain excellent appearance, mechanical properties, and especially weld strength. In terms of bending performance, it does not wrinkle when bent, and can maintain the bending performance based on repeated operations, is not easy to slip, and has high grip performance.

[0148] The thermoplastic resin molded article of the present invention can be used as a grip surface of electrical / electronic parts, automobile parts, mechanical parts, OA equipment, or housing parts of home appliances, general sundries, housing building materials, etc., or as a part of a housing.

[0149] Example

[0150] In order to further explain the present invention, the following examples and comparative examples are given for illustration. These examples do not limit the present invention. Unless otherwise specified, "%" means mass % and "part" means mass part.

[0151] The volume average particle size of the rubber polymer (a1) and the graft ratio of the rubber-containing graft copolymer (A) are measured by the following (1) and (2), respectively.

[0152] (1) Volume average particle size

[0153] The volume average particle size of the rubber polymer (a1) in the emulsion is measured at room temperature using "micro track UPA150" (trade name) manufactured by Honeywell. The unit is nm.

[0154] It is found that there is substantially no difference between the particle size of the rubber polymer (a1) in the emulsion and the rubber particle size of the rubber polymer (a1) in the resin composition using the rubber polymer (a1), and the former matches the latter.

[0155] (2) Grafting rate

[0156] The graft ratio of the rubber-containing graft copolymer (A) is calculated by the following formula.

[0157] Grafting rate (mass %) = {[(n) - (m) × L] / [(m) × L]} × 100

[0158] In the above formula, n is the following mass n(g): about 1 g [weighing: m(g)] of the rubber-containing graft copolymer (A) is put into 20 ml of acetone, shaken for 2 hours using an shaker at a temperature of 25°C, and then centrifuged for 60 minutes at a temperature of 5°C using a centrifuge (rotation speed; 23,000 rpm) to separate the acetone-insoluble component and the acetone-soluble component. The mass of the obtained acetone-insoluble component is the mass n(g).

[0159] L is the mass (g) of the rubber polymer (a1) contained in the rubber-containing graft copolymer (A). The mass of the rubber polymer (a1) can be calculated from the polymerization formula and polymerization conversion, or determined using infrared absorption spectroscopy.

[0160] [Rubber-containing graft copolymer (A)]

[0161] <Synthesis Example 1: Production of Rubber-Containing Graft Copolymer (A1)>

[0162] In a nitrogen-purged reactor, 120 parts of pure water, 0.5 parts of glucose, 0.5 parts of sodium pyrophosphate, 0.005 parts of ferrous sulfate, and 60 parts of a polybutadiene emulsion with a volume average particle size of 280 nm (in terms of solid content) were placed, and the temperature in the reactor was raised to 65°C under stirring. The moment when the internal temperature reached 65°C was regarded as the start of polymerization, and 30 parts of styrene, 10 parts of acrylonitrile, and 0.25 parts of a chain transfer agent tert-dodecyl mercaptan mixture were continuously added over 5 hours. Simultaneously, an aqueous solution containing a polymerization initiator cumene hydroperoxide (0.2 parts) and potassium oleate was continuously added over 7 hours to complete the reaction. 1 part of 2,2'-methylenebis(4-methyl-6-tert-butylphenol) was added to the obtained emulsion relative to 100 parts of the solid content of the emulsion. Next, the emulsion was coagulated with sulfuric acid, neutralized with sodium hydroxide, washed, filtered, and dried to obtain a powdery rubber-containing graft copolymer (A1).

[0163] The rubber content of the rubber-containing graft copolymer (A1) was 60% and the graft ratio was 55%.

[0164] <Synthesis Example 2: Production of Rubber-Containing Graft Copolymer (A2)>

[0165] The rubber-containing graft copolymer (A2) was obtained by the same method as that for the rubber-containing graft copolymer (A1) of Synthesis Example 1, except that the charging amount of the polybutadiene emulsion having a volume average particle size of 280 nm was changed to 40 parts (based on solid content), the added amount of styrene was changed to 45 parts, the added amount of acrylonitrile was changed to 15 parts, and the added amount of the chain transfer agent tert-dodecyl mercaptan mixture was changed to 0.28 parts.

[0166] The rubber content of the rubber-containing graft copolymer (A2) was 40% and the graft ratio was 95%.

[0167] [Thermoplastic elastomer (B)]

[0168] As the thermoplastic elastomer (B1), a hydrogenated block copolymer "Dynaron DR8903P" (trade name) manufactured by JSR Corporation, which is a styrene-ethylene-butylene-styrene copolymer (SEBS), was used (the styrene / butadiene mass ratio of the thermoplastic elastomer (B1) before hydrogenation was 35 / 65).

[0169] The thermoplastic elastomer (B1) had an MFR (230°C, 21.2 N) of 10 g / 10 min and an MFR (200°C, 49.0 N) of 4 g / 10 min.

[0170] [Other thermoplastic resins (C)]

[0171] <Synthesis Example 3: Production of Acrylonitrile-Styrene Resin (C1)>

[0172] In a nitrogen-purged reactor, 120 parts of water, 0.002 parts of alkylbenzene sulfonate soda, 0.5 parts of polyvinyl alcohol, 0.3 parts of azoisobutyl nitrile, 0.5 parts of tert-dodecyl mercaptan, and a monomer mixture consisting of 26 parts of acrylonitrile and 74 parts of styrene were used, and a portion of styrene was gradually added while heating from a starting temperature of 60° C. for 5 hours, and then the temperature was raised to 120° C. The reaction was further carried out at 120° C. for 4 hours, and then a polymer was taken out to obtain an acrylonitrile-styrene resin (C1) having acrylonitrile / styrene = 26 / 74 (mass ratio).

[0173] The mass average molecular weight (Mw) and molecular weight distribution (Mw / Mn) of the acrylonitrile-styrene resin (C1) were measured by GPC (GPC: "GPC / V2000" manufactured by Waters, column: "Shodex AT-G+AT-806MS" manufactured by Showa Denko K.K.) using o-dichlorobenzene (145° C.) as a solvent in terms of polystyrene. The results showed that the mass average molecular weight (Mw) was 110,000 and the molecular weight distribution (Mw / Mn) was 2.3.

[0174] <Aromatic polycarbonate resin (C2)>

[0175] As the aromatic polycarbonate resin (C2), "Iupilon S-2000F" (viscosity average molecular weight (Mv): 22,000) manufactured by Mitsubishi Engineering-Plastics Co., Ltd. was used.

[0176] <Polyacrylic acid resin (C3)>

[0177] As the polyacrylic acid-based resin (C3), "ACRYPET VH5" manufactured by Mitsubishi Chemical Corporation was used.

[0178] <Polybutylene terephthalate resin (C4)>

[0179] As the polybutylene terephthalate resin (C4), "NOVADURAN 5020" (intrinsic viscosity (30°C): 1.20 dl / g) manufactured by Mitsubishi Engineering-Plastics was used.

[0180] [Inorganic compounds (D)]

[0181] As the inorganic compound (D1), "A-21 (product name)" manufactured by Yamaguchi-Mica Co., Ltd. (wet-pulverized muscovite, volume average particle size of 22 μm, aspect ratio of 70) was used.

[0182] [Examples 1 to 8 and Comparative Examples 1 to 6]

[0183] <Preparation of Thermoplastic Resin Composition>

[0184] The components (A), (B), (C), and (D) shown in the following Tables 1A and 1B are mixed in the mixing ratios shown in Tables 1A and 1B. Thereafter, 0.2 parts of ADKSTAB "A-60 (trade name)" (tetrakis[methylene-3-(3',5'-di-tert-butyl-4'-hydroxyphenyl)propionate]methane) manufactured by ADEKA Corporation is mixed, and melt-kneading is performed at a barrel temperature of 220°C using a twin-screw extruder (model name "TEX44, The Japan Steel Works") to form pellets. The pellets of the obtained thermoplastic resin composition are used to produce the following molded products (1) to (4), which are respectively subjected to the following measurements and evaluations. The evaluation results are shown in Tables 1A and 1B.

[0185] <Production of Molded Products (1)>

[0186] An injection molding machine "IS100GN" (trade name) manufactured by TOSHIBA MACHINE was used to prepare a test piece of 120 mm × 80 mm × 2 mm under the conditions of a resin temperature of 220°C, a mold temperature of 50°C, an injection speed of 40 mm / s, and an injection pressure of 100 MPa. As a molding mold, a mold for leather grain (texture No.; TH-894) having concavoconvexity on the inner surface (the depth of the concave portion is 100 μm) was used.

[0187] <Production of Molded Products (2)>

[0188] A dumbbell-shaped test piece (without weld) having a gate on one side was prepared using an injection molding machine "J110AD-180H" (model name) manufactured by Nippon Steel Works, Ltd., with a barrel setting temperature of 220° C. and a mold temperature of 50° C. Next, the center portion of the dumbbell-shaped test piece was cut out to prepare a test piece without weld (size: 80×10×4 mm).

[0189] <Production of Molded Products (3)>

[0190] A dumbbell-shaped test piece with a weld was produced using a mold having gates at both ends and a weld formed in the center of the test piece, using an injection molding machine "J110AD-180H" (model name) manufactured by The Japan Steel Works, Ltd., with a barrel setting temperature of 220° C. and a mold temperature of 50° C. Next, the center portion of the dumbbell-shaped test piece with a weld was cut out to produce a test piece (size: 80×10×4 mm) with a weld in the center portion.

[0191] <Production of Molded Product (4)>

[0192] A test piece (size: 80×10×4 mm) having a gate on one side was prepared using an injection molding machine "J110AD-180H" (model name) manufactured by The Japan Steel Works, Ltd. with a cylinder setting temperature of 220°C and a mold temperature of 50°C.

[0193] <Determination of hardness>

[0194] Using the molded article (4), the Rockwell hardness (hardness grade: R grade) was measured at room temperature in accordance with ISO2039.

[0195] <Measurement of flexural strength>

[0196] Using the molded article (2), the flexural yield strength (FS0) was measured in accordance with ISO 178. The unit of the measured value is MPa.

[0197] <Measurement of Bending Strength of Weld Seam>

[0198] Using the molded article (3), the flexural yield strength (FS1) was measured in accordance with ISO 178. The unit of the measured value is MPa.

[0199] <Evaluation of weld strength retention rate>

[0200] The weld strength retention rate (%) is calculated using the following formula for the bending yield strength (FS0) of the weld without weld and the bending yield strength (FS1) of the weld measured according to ISO 178. The higher the retention rate, the stronger the weld strength. In practical applications, the retention rate needs to be 70% or more.

[0201] Weld strength retention rate (%) = (FS1) / (FS0)×100

[0202] <Measurement of flexural modulus>

[0203] Using the molded article (2), the flexural modulus was measured in accordance with ISO 178. The unit of the measured value is MPa.

[0204] <Determination of Deformation Temperature under Load (Heat Deformation Temperature: HDT)>

[0205] Using the molded product (4), measure the heat distortion temperature in accordance with ISO 75 (flat pulling method, Method B, load 1.82 MPa). The unit of the measured value is °C.

[0206] <Evaluation of the appearance of the molded product>

[0207] Using the molded product (1), visually observe both the textured surface and the mirror surface of the molded product, and evaluate according to the following criteria.

[0208] ○: (i) Flow marks, (ii) Delamination, and (iii) Whitening are not generated.

[0209] △: Any one of (i) flow marks, (ii) delamination, and (iii) whitening is generated in a part of the molded product.

[0210] ×: Any one of (i) flow marks, (ii) delamination, and (iii) whitening is generated on the entire surface of the molded product.

[0211] <Evaluation of the touch (grip feeling)>

[0212] Evaluate the touch when tracing the textured surface of the molded product (1) with a finger at room temperature of 23°C according to the following criteria.

[0213] ○: Not easy to slide.

[0214] △: Slightly not easy to slide.

[0215] ×: Easy to slide.

[0216] <Measurement of the MIU value (KES hand feel measurement)>

[0217] Measure the MIU value of the textured surface of the molded product (1) using the "Friction Sensation Tester KES-SE" (trade name) manufactured by Katotech Co., Ltd. The MIU value (average coefficient of friction) is an index of non-slip property, and the higher the value, the less easy it is to slide.

[0218] <Evaluation of bending wrinkling>

[0219] Bend the molded product (1) 20 degrees to the side opposite to the textured surface (glossy surface side), visually observe the bent side (glossy surface side), and evaluate according to the following criteria.

[0220] ○: No wrinkles are generated.

[0221] ×: Wrinkles are generated.

[0222] <Evaluation of repeated bending wrinkling>

[0223] The molded article (1) was bent 20 degrees to the opposite side of the textured surface (glossy side) and then returned to its original state. This operation of bending 20 degrees was repeated 30 times, and then the bent side (glossy side) was visually observed and evaluated according to the following criteria.

[0224] ○: No wrinkles were generated.

[0225] △: Slight wrinkles were generated.

[0226] ×: Wrinkles were generated.

[0227] <Moldability Evaluation 1>

[0228] The molded article (1) was evaluated for its releasability from the mold after molding according to the following criteria.

[0229] ○: No sticking, qualified products are automatically taken out.

[0230] △: Slightly adhered, and qualified products were removed manually.

[0231] ×: Strong adhesion, no qualified products were taken out.

[0232] <Moldability Evaluation 2>

[0233] The following items were investigated as deformation and discoloration caused by the ejector pin after molding the molded product (1), and evaluated according to the following criteria.

[0234] The presence or absence of deformation (defects such as damage, breakage, peeling, etc.) and discoloration (whitening, etc.) around the ejector pin marks at four locations on the back side of the textured surface of the molded product (1)

[0235] ○: No deformation or discoloration, qualified products were taken out.

[0236] △: No deformation but discoloration.

[0237] ×: Causes deformation and discoloration.

[0238] [Table 1A]

[0239]

[0240]

[0241] ※ The content in parentheses is the content (mass %) of the rubber polymer (a1) in the rubber-containing graft copolymer (A) [Table 1B]

[0242]

[0243]

[0244] ※ The content in parentheses is the content (mass %) of the rubber polymer (a1) in the rubber-containing graft copolymer (A)

[0245] The following can be seen from Tables 1A and 1B above.

[0246] Examples 1 to 8 using the thermoplastic resin composition of the present invention were excellent in hardness, flexural modulus and appearance of molded products, as well as tactile feel (grip), non-slip properties (MIU value), bending wrinkling resistance and repeated bending wrinkling resistance.

[0247] In Comparative Examples 1 to 5 which did not contain the inorganic compound (D) and did not satisfy the requirements of the present invention, performance such as weld strength, appearance, bending wrinkling, and repetitive characteristics thereof were inferior.

[0248] In Comparative Example 6 in which the inorganic compound (D) was contained but the content of (a1)-(B) exceeded 15 mass %, the weld strength, bending wrinkling resistance, and the repetitive characteristics thereof were inferior.

[0249] Although the present invention has been described in detail using specific embodiments, it will be apparent to one skilled in the art that various modifications can be made without departing from the spirit and scope of the present invention.

[0250] This application is based on Japanese Patent Application No. 2020-069838 filed on April 8, 2020 and Japanese Patent Application No. 2020-140258 filed on August 21, 2020, the entire contents of which are incorporated herein by reference.

[0251] Industrial Applicability

[0252] The thermoplastic resin molded article of the present invention using the thermoplastic resin composition of the present invention has excellent mechanical strength and molded article appearance, and the surface is not easy to slip, and the tactile feeling such as grip is good, so it can be appropriately used for operations with hands or appropriately used as an item that is not easy to slip out of the hand, and can provide a product that can maintain bending performance based on repeated operations, is not easy to slide, and has high grip performance. In addition, it is not limited to the grip of the hand, and can also be used as a component of the grounding surface of a personal computer or a printer, etc. to show an anti-slip effect, etc., and its usefulness is extremely high.

Claims

1. A thermoplastic resin composition comprising 7% to 64% by mass of a rubber-containing graft copolymer (A), 2% to 35% by mass of a thermoplastic elastomer (B), 0.5% to 90% by mass of a polycarbonate resin, a polyacrylic resin or a polybutylene terephthalate resin (C), and 0.5% to 20% by mass of an inorganic compound (D), wherein: The total of (A), (B), (C) and (D) is 100% by mass, and the thermoplastic resin composition is characterized in that: The rubber-containing graft copolymer (A) is a graft copolymer obtained by graft-polymerizing 20 to 65 parts by mass of a vinyl monomer mixture (a2) containing an aromatic vinyl monomer and a cyanide vinyl monomer with 35 to 80 parts by mass of a rubber polymer (a1), wherein the total amount of the rubber polymer (a1) and the vinyl monomer mixture (a2) is 100 parts by mass. The content of the rubber polymer (a1) is 2 to 35% by mass in 100% by mass of the total of (A), (B), (C) and (D). The difference between the content of the rubber polymer (a1) in mass % and the content of the thermoplastic elastomer (B) in mass % in 100 mass % of the total of (A), (B), (C) and (D) is within 15 mass %.

2. The thermoplastic resin composition according to claim 1, wherein The volume average particle size of the rubber polymer (a1) is 100nm to 1500nm, and in 100% by mass of the vinyl monomer mixture (a2), the ratio of aromatic vinyl monomer to cyanide vinyl monomer is aromatic vinyl monomer / cyanide vinyl monomer = 50% to 95% by mass / 50% to 5% by mass, and the grafting rate of the rubber-containing graft copolymer (A) is 20% to 100% by mass.

3. The thermoplastic resin composition according to claim 1 or 2, wherein The thermoplastic elastomer (B) has an MFR of 1 g / 10 min to 25 g / 10 min at 200° C. and 49.0 N, and an MFR of 3 g / 10 min to 30 g / 10 min at 230° C. and 21.2 N.

4. The thermoplastic resin composition according to claim 1 or 2, wherein The thermoplastic elastomer (B) is a styrene-based elastomer, which is a block copolymer and / or a hydrogenated product thereof containing one or more polymer blocks P of an aromatic vinyl compound and one or more polymer blocks Q of a conjugated diene compound, respectively, with a mass average molecular weight of 10,000 to 800,000, a content of the polymer block P of 5% to 60% by mass, and a content of the polymer block Q of 95% to 40% by mass.

5. The thermoplastic resin composition according to claim 1 or 2, wherein The inorganic compound (D) is muscovite. 6 . A thermoplastic resin molded article obtained by molding the thermoplastic resin composition according to claim 1 .

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