Method for producing thermoplastic resin composite molded product

Abstract

To provide a method for producing a composite molded product that has high bonding strength between different materials and excellent airtightness even after long-term environmental treatment.SOLUTION: A thermoplastic elastomer resin composition (Y) contains 66 to 98.98 mass% of a polyester block copolymer containing a crystalline aromatic polyester unit and an aliphatic polyether unit and / or an aliphatic polyester unit and having a melting point of less than 210°C, 1 to 30 mass% of a polyvinyl alcohol resin, a silane coupling agent and an antioxidant. A method for producing a thermoplastic resin composite molded product includes: a step A in which a metal member (Z) is inserted into a mold to be molded and the mold is covered with the thermoplastic elastomer resin composition (Y) by injection molding; a step B in which the molded product obtained in the step A is inserted into the mold, and the mold is covered with a thermoplastic resin (X) by injection molding; and a step C in which the molded product obtained in the step B is subjected to a heat treatment at a melting point +21°C to a melting point +50°C of the thermoplastic elastomer resin composition (Y).SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a method for producing a thermoplastic resin composite molded article having a metal member inserted therein, and in particular to a method for producing a thermoplastic resin composite molded article having excellent airtightness between metal and thermoplastic resin. [Background technology]

[0002] Portable electronic devices such as mobile phones, laptops, tablets, etc. require airtightness and waterproofness to prevent moisture and water from entering the inside of the electronic devices. Vehicles such as automobiles also require airtightness such as waterproofing, oil resistance, and dust resistance because many electronic devices, sensors, connectors, etc. are installed in the vehicles.

[0003] Thermoplastic resins have been widely used in portable electronic devices due to their small size, light weight, low cost, and freedom of shape, but light metals such as aluminum alloys are now being used as parts of the housing to further improve strength and rigidity. There is also concern about water and oil penetrating sensors and connectors from the interface between the metal terminals and thermoplastic resin.

[0004] Therefore, Patent Document 1 proposes a method in which the surface of the metal to be inserted is treated with an alkaline or acidic solution, and then the metal treated with a silane coupling agent is inserted into an injection molding die, Patent Document 2 proposes a method in which a groove is formed on the surface of a metal member in a direction that crosses the direction in which the airtightness of the joining interface is required, and then the metal is joined to a molten thermoplastic resin by injection molding, etc., and Patent Document 3 proposes a method in which the surface to be joined where a connector is formed is roughened, or a nitrogen-containing compound is adsorbed to form a countless uneven or porous layer, and then injection molding is performed on the surface to integrate the connector with the thermoplastic resin. Patent Document 4 proposes a thermoplastic resin composite molded product that can obtain airtightness by interposing a thermoplastic elastomer resin composition between the metal and the thermoplastic resin composition. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2003-103562 A [Patent Document 2] JP 2011-240685 A [Patent Document 3] JP 2012-179709 A [Patent Document 4] Patent No. 6420094 Summary of the Invention [Problem to be solved by the invention]

[0006] However, the methods of Patent Documents 1 to 3 have the problem that the surface of the insert metal needs to be specially treated, which not only makes the work complicated and reduces productivity, but also makes it impossible to obtain sufficient airtightness by simply increasing the contact area. Patent Document 4 shows that there is no need to apply special treatment to the metal surface, and it is possible to obtain stable airtightness even after short-term environmental treatment.

[0007] The present invention has been achieved as a result of intensive research aimed at solving the problems in the prior art described above. That is, the present invention aims to provide a method for producing a thermoplastic resin composite molded product that has high bonding strength between different materials without requiring special treatment on the surface of the insert metal and has excellent airtightness even after long-term environmental treatment. [Means for solving the problem]

[0008] That is, the present invention constitutes [1] to [3]. [1] A method for producing a thermoplastic resin composite molded product in which a thermoplastic elastomer resin composition (Y) is interposed between a metal member (Z) and a thermoplastic resin (X) in a shape covering at least a part of the entire circumference of the metal member (Z), the thermoplastic elastomer resin composition (Y) containing a hard segment (a1) composed of a crystalline aromatic polyester unit and a soft segment (a2) composed of an aliphatic polyether unit and / or an aliphatic polyester unit, and containing 66 to 98.98 mass% of a polyester block copolymer (A) having a melting point of less than 210°C, 1 to 30 mass% of a polyvinyl alcohol resin (B), 0.01 to 5.0 mass% of a silane coupling agent (C), and 0.01 to 5.0 mass% of an antioxidant (D); (Step A) a step of inserting a metal member (Z) into a mold for molding a molded article in which the metal member (Z) is covered with the thermoplastic elastomer resin composition (Y), and injection-molding the thermoplastic elastomer resin composition (Y) into the mold to cover the metal member (Z) with the thermoplastic elastomer resin composition (Y); (Step B) a step of inserting the molded article obtained in (Step A) into a mold for molding a molded article in which the thermoplastic resin (X) is covered with a metal member (Z) and a thermoplastic elastomer composition (Y), and then injection-molding the thermoplastic resin (X) into the mold, thereby covering the molded article in which the thermoplastic elastomer composition (Y) is covered with the metal member (Z) with the thermoplastic resin (X); (Step C) A method for producing a thermoplastic resin composite molded product, further comprising a step of subjecting the molded article, in which the thermoplastic resin (X) covers the metal member (Z) and the thermoplastic elastomer composition (Y), to a heat treatment at a temperature of melting point +21°C to melting point +50°C of the thermoplastic elastomer resin composition (Y). [2] A method for producing a thermoplastic resin composite molding according to claim 1, wherein the hard segment (a1) consisting of a crystalline aromatic polyester unit of the thermoplastic elastomer resin composition (Y) consists of a polybutylene terephthalate unit derived from terephthalic acid and / or dimethyl terephthalate and 1,4-butanediol, and a polybutylene isophthalate unit derived from isophthalic acid and / or dimethyl isophthalate and 1,4-butanediol. [3] A method for producing a thermoplastic resin composite molding according to claim 1, wherein the thermoplastic resin (X) is primarily composed of at least one resin selected from the group consisting of polyphenylene sulfide resin, polyethylene terephthalate resin, polybutylene terephthalate resin, polycarbonate resin, liquid crystal polyester resin, and polyamide resin. Effect of the Invention

[0009] The method for producing a thermoplastic resin composite molded article of the present invention ensures that different materials are firmly bonded together and that the material retains excellent airtightness even after long-term environmental treatment.

[0010] Since the thermoplastic resin composite molded article of the present invention provides sufficient airtightness between the metal member and the molded article made of the thermoplastic resin composition, it can be suitably used as parts that require sealing properties such as waterproofing, oil resistance, and dust resistance in automobile parts, electrical equipment, electrical and electronic parts, industrial products, etc.

[0011] The thermoplastic resin composite molded product of the present invention has high bonding strength and excellent airtightness, and is therefore suitable for use as electrical / electronic component integrated module components and as components into which metals are inserted, such as motors and batteries, and for which permeation of water vapor, liquids, etc. must be reduced. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1 is a schematic diagram of the thermoplastic resin composite molded articles used in Examples 1 to 12 and Comparative Examples 1 to 4. As shown in FIG. [Diagram 2] FIG. 1 is a schematic cross-sectional view of a thermoplastic resin composite molded article used in Examples 1 to 12 and Comparative Examples 1 to 4. [Diagram 3] FIG. 3 shows the dimensions of the metal terminals and thermoplastic resin composite molded products used in Examples 1 to 12 and Comparative Examples 1 to 4. [Figure 4] FIG. 1 is a schematic diagram of a leakage test. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] The present invention will be described in detail below.

[0014] The present invention provides a method for producing an airtight thermoplastic resin composite molded article in which a molded article having a thermoplastic elastomer resin composition (Y) interposed between a metal member (Z) and a thermoplastic resin (X) is heat-treated at a temperature between the melting point of the thermoplastic elastomer resin composition (Y) +21°C to the melting point of the thermoplastic elastomer resin composition (Y) +50°C, thereby integrating the metal member (Z) and the thermoplastic resin (X).

[0015] The metal member (Z) in the present invention will be described.

[0016] The metal member may be aluminum, aluminum alloys, magnesium, magnesium alloys, copper, copper alloys, iron, steel, stainless steel, nickel, nickel alloys, titanium, titanium alloys, tin, zinc, cobalt, chromium, chromium alloys, zirconium, beryllium, beryllium alloys, etc., and known materials in which these are combined with surface treatments such as plating may also be used. Among these, aluminum, aluminum alloys, copper, copper alloys, nickel, nickel alloys, and tin are preferably used.

[0017] Examples of the thermoplastic resin (X) include polypropylene resin, polyethylene resin, ABS resin, polycarbonate resin, polyacetal resin, polyethylene terephthalate resin, polybutylene terephthalate resin, polyphenylene sulfide resin, polyamide resin, liquid crystal polyester resin, polyimide resin, syndiotactic polystyrene resin, and polycyclohexane dimethylene terephthalate resin. Among these, ABS resin, polycarbonate resin, polybutylene terephthalate resin, polyethylene terephthalate resin, polytrimethylene terephthalate resin, polyphenylene sulfide resin, liquid crystal polyester resin, polyimide resin, syndiotactic polystyrene resin, and polycyclohexane dimethylene terephthalate resin are preferably used in view of excellent bonding strength with the thermoplastic elastomer resin composition. These can be used not only as a single polymer but also as an alloy resin of two or more kinds by compounding or the like. It is also possible to compound fillers, such as glass fiber, carbon fiber, aramid fiber, and other similar high-strength fibers, as well as fillers for resins, such as calcium carbonate, magnesium carbonate, silica, talc, and clay.

[0018] More preferably, the thermoplastic resin (X) contains, as a main component, at least one resin selected from the group consisting of polyphenylene sulfide resin, polyethylene terephthalate resin, polybutylene terephthalate resin, polycarbonate resin, liquid crystal polyester resin, and polyamide resin.

[0019] The thermoplastic elastomer resin composition (Y) used in the present invention contains 66 to 98.98 mass% of a polyester block copolymer (A) having a melting point of less than 210° C., 1 to 30 mass% of a polyvinyl alcohol resin (B), 0.01 to 5.0 mass% of a silane coupling agent (C), and 0.01 to 5.0 mass% of an antioxidant (D). In the thermoplastic elastomer resin composition (Y) used in the present invention, the total of the polyester block copolymer (A) having a melting point of less than 210° C., the polyvinyl alcohol resin (B), the silane coupling agent (C), and the antioxidant (D) is 100 mass%.

[0020] The polyester block copolymer (A) used in the present invention contains a hard segment (a1) consisting of a crystalline aromatic polyester unit, and a soft segment (a2) consisting of an aliphatic polyether unit and / or an aliphatic polyester unit.

[0021] The hard segment (a1) is a polyester formed from an aromatic dicarboxylic acid or an ester-forming derivative thereof, and a diol or an ester-forming derivative thereof.

[0022] Specific examples of aromatic dicarboxylic acids constituting the hard segment (a1) of the polyester block copolymer (A) include terephthalic acid, isophthalic acid, phthalic acid, naphthalene-2,6-dicarboxylic acid, naphthalene-2,7-dicarboxylic acid, anthracene dicarboxylic acid, diphenyl-4,4'-dicarboxylic acid, diphenoxyethane dicarboxylic acid, 4,4'-diphenyl ether dicarboxylic acid, 5-sulfoisophthalic acid, and sodium 3-sulfoisophthalate. Furthermore, ester-forming derivatives of aromatic dicarboxylic acids, such as lower alkyl esters, aryl esters, carbonate esters, and acid halides, can of course be used equally. In the present invention, the aromatic dicarboxylic acids are mainly used, but a part of the aromatic dicarboxylic acids may be replaced with alicyclic dicarboxylic acids such as 1,4-cyclohexane dicarboxylic acid, cyclopentane dicarboxylic acid, and 4,4'-dicyclohexyl dicarboxylic acid, or aliphatic dicarboxylic acids such as adipic acid, succinic acid, oxalic acid, sebacic acid, dodecanedioic acid, and dimer acid. Furthermore, ester-forming derivatives of dicarboxylic acids, such as lower alkyl esters, aryl esters, carbonates, and acid halides, can of course be used equally well.

[0023] In the present invention, it is preferable to use two or more of the dicarboxylic acids, such as combinations of terephthalic acid and isophthalic acid, terephthalic acid and dodecanedioic acid, terephthalic acid and dimer acid, etc. By using two or more dicarboxylic acid components, the crystallinity of the hard segment (a1) can be reduced, flexibility can be imparted, and the thermal adhesion to other thermoplastic resins can be improved.

[0024] Next, the diol that forms an ester with the aromatic dicarboxylic acid etc. will be described. Specific examples of the diol used in the present invention include diols having a molecular weight of 400 or less, such as aliphatic diols such as 1,4-butanediol, ethylene glycol, trimethylene glycol, pentamethylene glycol, hexamethylene glycol, neopentyl glycol, and decamethylene glycol, alicyclic diols such as 1,1-cyclohexanedimethanol, 1,4-dicyclohexanedimethanol, and tricyclodecane dimethanol, and aromatic diols such as xylylene glycol, bis(p-hydroxy)diphenyl, bis(p-hydroxy)diphenylpropane, 2,2'-bis[4-(2-hydroxyethoxy)phenyl]propane, bis[4-(2-hydroxyethoxy)phenyl]sulfone, 1,1-bis[4-(2-hydroxyethoxy)phenyl]cyclohexane, 4,4'-dihydroxy-p-terphenyl, and 4,4'-dihydroxy-p-quaterphenyl. Such diols may also be used in the form of ester-forming derivatives, such as acetylated forms, alkali metal salts, etc. These diol components and their derivatives may be used in combination of two or more kinds.

[0025] Preferred examples of such hard segment (a1) are those consisting of polybutylene terephthalate units derived from terephthalic acid and / or dimethyl terephthalate and 1,4-butanediol, those consisting of polybutylene isophthalate units derived from isophthalic acid and / or dimethyl isophthalate and 1,4-butanediol, and copolymers of both of these. Particularly preferred are copolymers having polybutylene terephthalate units derived from terephthalic acid and / or dimethyl terephthalate and 1,4-butanediol, and polybutylene terephthalate units and polybutylene isophthalate units derived from isophthalic acid and / or dimethyl isophthalate and 1,4-butanediol.

[0026] The soft segment (a2) of the polyester block copolymer (A) of the thermoplastic elastomer resin composition (Y) used in the present invention is composed of an aliphatic polyether and / or an aliphatic polyester unit. Examples of the aliphatic polyether include poly(ethylene oxide) glycol, poly(propylene oxide) glycol, poly(tetramethylene oxide) glycol, poly(hexamethylene oxide) glycol, copolymers of ethylene oxide and propylene oxide, ethylene oxide addition polymers of poly(propylene oxide) glycol, and copolymer glycols of ethylene oxide and tetrahydrofuran.

[0027] Examples of aliphatic polyesters include poly(ε-caprolactone), polyenantholactone, polycaprylolactone, polybutylene adipate, and polyethylene adipate. As these soft segments (a2), poly(tetramethylene oxide) glycol, ethylene oxide adduct of poly(propylene oxide) glycol, copolymer glycol of ethylene oxide and tetrahydrofuran, poly(ε-caprolactone), polybutylene adipate, and polyethylene adipate are preferably used from the viewpoint of the elastic properties of the resulting polyester block copolymer (A), and among these, poly(tetramethylene oxide) glycol, ethylene oxide adduct of poly(propylene oxide) glycol, and copolymer glycol of ethylene oxide and tetrahydrofuran are particularly preferably used. Furthermore, the number average molecular weight of these soft segments (a2) is preferably about 300 to 6000 in the copolymerized state.

[0028] In the polyester block copolymer (A) used in the present invention, the copolymerization amount of the hard segment (a1) and the soft segment (a2) is usually 5 to 80 mass% for the hard segment (a1) and 20 to 95 mass% for the soft segment (a2), and preferably 10 to 75 mass% for the hard segment (a1) and 25 to 90 mass% for the soft segment (a2).

[0029] The polyester block copolymer (A) used in the present invention has a melting point of less than 210° C. In the present invention, the melting point of the polyester block copolymer (A) is measured by a differential scanning calorimeter (DSC), and means that the measured melting point is less than 210° C. When a polyester block copolymer (A) having a melting point of 210° C. or more is used, polyvinyl alcohol resin (B) described below is dispersed coarsely in the polyester block copolymer (A), resulting in a decrease in bonding strength with members made of materials other than thermoplastic resins.

[0030] The polyester block copolymer (A) used in the present invention can be produced by a known method.Specific examples thereof include a method of transesterifying an ester-forming derivative such as a lower alcohol diester of an aromatic dicarboxylic acid, an excess amount of a diol (low molecular weight glycol), and a soft segment (a2) component in the presence of a catalyst, and polycondensing the resulting reaction product, and a method of esterifying an aromatic dicarboxylic acid, an excess amount of a diol, and a soft segment (a2) component in the presence of a catalyst, and polycondensing the resulting reaction product.

[0031] In the thermoplastic elastomer resin composition (Y) used in the present invention, the content of the polyester block copolymer (A) is 66% by mass to 98.98% by mass, and particularly preferably 76% by mass to 97% by mass. If the content of the polyester block copolymer (A) is less than 66% by mass, the resulting thermoplastic elastomer resin composition (Y) has low mechanical properties and poor moldability, whereas if it exceeds 98.98% by mass, the bonding strength is reduced.

[0032] Examples of the polyvinyl alcohol resin (B) used in the present invention include polyvinyl butyral resin, polyvinyl acetal resin, etc. Commercially available products can be used as the polyvinyl alcohol resin (B) used, such as Sflex BL-1, BL-2, BX-L, BM-S, KS-3, etc. manufactured by Sekisui Chemical Co., Ltd., and Denka Butyral 3000-1, 3000-2, 3000-4, 4000-2, etc. manufactured by Denki Kagaku Kogyo Co., Ltd.

[0033] In the thermoplastic elastomer resin composition (Y) used in the present invention, the content of the polyvinyl alcohol resin (B) is 1% by mass to 30% by mass, and particularly preferably 3% by mass to 20% by mass. If the content of the polyvinyl alcohol resin (B) is less than 1% by mass, the bonding strength is low, and if it exceeds 30% by mass, the mechanical strength of the obtained thermoplastic elastomer resin composition (Y) is low and the moldability is also poor.

[0034] The silane coupling agent (C) used in the present invention is not particularly limited, but is preferably one having an amino group, an epoxy group, a vinyl group, an allyl group, a methacryl group, a sulfide group, or the like in one molecule, and among them, a silane coupling agent (C) having an epoxy group is preferably used. Specific examples of the silane coupling agent (C) include 3-aminopropyltrimethoxysilane, 3-aminopropylethoxysilane, 3-(2-aminoethyl)aminopropyltrimethoxysilane, 3-(2-aminoethyl)aminopropylmethyldimethoxysilane, 3-phenylaminopropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, Examples of suitable silanes include 3-(triethoxysilyl)propyl)sulfide, bis(3-(triethoxysilyl)propyl)tetrasulfide, vinyltriacetoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, acryltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, and the like. Preferred are epoxy group-containing compounds, and these can be used alone or in combination of two or more.

[0035] In the thermoplastic elastomer resin composition (Y) used in the present invention, the content of the silane coupling agent (C) is 0.01% by mass to 5% by mass, preferably 0.05% by mass to 3% by mass, and more preferably 0.1% by mass to 1.5% by mass. If the content of the silane coupling agent (C) is less than 0.01% by mass, the bonding strength is low, and if it exceeds 5% by mass, blooming occurs and the thermal stability is reduced.

[0036] The antioxidant (D) used in the present invention may be one or more selected from the group consisting of aromatic amine-based antioxidants, hindered phenol-based antioxidants, sulfur-based antioxidants, and phosphorus-based antioxidants, and among these, aromatic amine-based antioxidants are preferably used.

[0037] Specific examples of aromatic amine-based antioxidants include phenylnaphthylamine, 4,4'-dimethoxydiphenylamine, 4,4'-bis(α,α-dimethylbenzyl)diphenylamine, and 4-isopropoxydiphenylamine, and among these, the use of diphenylamine-based compounds is preferred.

[0038] Specific examples of hindered phenol-based antioxidants include 2,4-dimethyl-6-t-butylphenol, 2,6-di-t-butylphenol, 2,6-di-t-butyl-p-cresol, hydroxymethyl-2,6-di-t-butylphenol, 2,6-di-t-butyl-α-dimethylamino-p-cresol, 2,5-di-t-butyl-4-ethylphenol, 4,4'-bis(2,6-di-t-butylphenol), 2,2'-methylene-bis-4-methyl-6-t-butylphenol, 2,2'-methylene-bis(4-ethyl-6-t-butylphenol), phenol), 4,4'-methylene-bis(6-t-butyl-o-cresol), 4,4'-methylene-bis(2,6-di-t-butylphenol), 2,2'-methylene-bis(4-methyl-6-cyclohexylphenol), 4,4'-butylidene-bis(3-methyl-6-t-butylphenol), 4,4'-thiobis(6-t-butyl-3-methylphenol), bis(3-methyl-4-hydroxy-5-t-butylbenzyl)sulfide, 4,4'-thiobis(6-t-butyl-o-cresol), 2,2'-thiobis(4-methyl-6-t-butyl 2,6-bis(2'-hydroxy-3'-t-butyl-5'-methylbenzyl)-4-methylphenol, diethyl ester of 3,5-di-t-butyl-4-hydroxybenzenesulfonic acid, 2,2'-dihydroxy-3,3'-di(α-methylcyclohexyl)-5,5'-dimethyl-diphenylmethane, α-octadecyl-3(3',5'-di-t-butyl-4'-hydroxyphenyl)propionate, 6-(hydroxy-3,5-di-t-butylanilino)-2,4-bis-octyl-thio-1,3,5-triazine, hexamethion ethylene glycol-bis[β-(3,5-di-t-butyl-4-hydroxyphenol)propionate], N,N'-hexamethylene-bis(3,5-di-t-butyl-4-hydroxyhydrocinnamic acid amide), 2,2-thio[diethyl-bis-3(3,5-di-t-butyl-4-hydroxyphenyl)propionate], dioctadecyl ester of 3,5-di-t-butyl-4-hydroxybenzenephosphonic acid, tetrakis[methylene-3(3,5-di-t-butyl-4-hydroxyphenyl)propionate]methane, 1,3,5-trimethyl-2,4,Examples of such compounds include 6-tris(3,5-di-t-butyl-4-hydroxybenzyl)benzene, 1,1,3-tris(2-methyl-4-hydroxy-5-di-t-butylphenyl)butane, tris(3,5-di-t-butyl-4-hydroxyphenyl)isocyanurate, and tris[β-(3,5-di-t-butyl-4-hydroxyphenyl)propionyl-oxyethyl]isocyanurate. Among these, it is particularly preferable to use compounds having a molecular weight of 500 or more, such as tetrakis[methylene-3(3,5-di-t-butyl-4-hydroxyphenyl)propionate]methane.

[0039] The sulfur-based antioxidants are compounds containing sulfur, such as thioethers, dithioacid salts, mercaptobenzimidazoles, thiocarbanilides, and thiodipropionates. Among these, it is particularly preferable to use thiodipropionates.

[0040] The phosphorus-based antioxidants are compounds containing phosphorus, such as phosphoric acid, phosphorous acid, hypophosphorous acid derivatives, phenylphosphonic acid, polyphosphonates, dialkyl pentaerythritol diphosphites, and dialkyl bisphenol A diphosphites. Among these, it is preferable to use a compound having both a phosphorus atom and a sulfur atom in the molecule, or a compound having two or more phosphorus atoms in the molecule.

[0041] In the thermoplastic elastomer resin composition (Y) used in the present invention, the content of these antioxidants (D) is 0.01 mass% to 5 mass%, preferably 0.05 mass% to 3 mass%, and more preferably 0.1 mass% to 1.5 mass%. If the content of the antioxidant (D) is less than 0.01 mass%, the heat resistance, particularly the long-term heat aging resistance, of the thermoplastic elastomer resin composition (Y) is poor, and copper damage may occur when bonding with metal. If the content exceeds 5 mass%, blooming occurs, and the mechanical strength of the thermoplastic elastomer resin composition (Y) is reduced.

[0042] Furthermore, various additives can be added to the thermoplastic elastomer resin composition (Y) used in the present invention within the scope of the present invention. For example, molding aids such as known crystal nucleating agents and lubricants, light resistance agents such as ultraviolet absorbers and hindered amine compounds, hydrolysis resistance improvers, colorants such as pigments and dyes, antistatic agents, conductive agents, flame retardants, reinforcing agents, fillers, plasticizers, and mold release agents can be optionally contained. The thermoplastic elastomer resin composition (Y) used in the present invention can be produced by, for example, feeding raw materials containing a polyester block copolymer (A), a polyvinyl alcohol resin (B), a silane coupling agent (C), and an antioxidant (D) to a screw extruder and melt-kneading the raw materials. The thermoplastic elastomer resin composition (Y) obtained by the above method can also be pelletized and used for subsequent molding.

[0043] In the thermoplastic resin composite molding of the present invention, the thermoplastic elastomer resin composition (Y) can be interposed between the metal member (Z) and the thermoplastic resin (X) by, for example, coating the portion of the thermoplastic resin composition (X) that contacts the surface of the metal member (Z) with the thermoplastic elastomer resin composition (Y), and then laminating the thermoplastic resin (X) on the surface of the thermoplastic elastomer resin composition (Y).

[0044] In the thermoplastic resin composite molded product of the present invention, the thermoplastic elastomer resin composition (Y) preferably covers the entire circumference of at least a portion of the metal member (Z), and the thermoplastic elastomer resin composition (Y) bonds the metal member (Z) to the thermoplastic resin (X) between the metal member (Z) and the thermoplastic resin (X). In particular, by providing a portion of the metal member (Z) whose entire circumference is covered with the thermoplastic elastomer resin composition (Y), a structure is formed in which the thermoplastic elastomer resin composition (Y) is always present between the metal (Z) and the thermoplastic resin composition (X), and the thermoplastic elastomer resin composition (Y) is present between them and bonds them to provide airtightness.

[0045] Methods for coating the thermoplastic elastomer resin composition (Y) on the metal member (Z) include a method of wrapping a sheet of the thermoplastic elastomer resin composition (Y), a method of spraying a powder of the thermoplastic elastomer resin composition (Y), and a method of inserting the metal (Z) into a mold of an injection molding machine and injection molding the thermoplastic elastomer resin composition (Y) to coat specific locations. In order to accurately control the workability and coating dimensions, the method of coating by injection molding is most preferred.

[0046] The thickness of the thermoplastic elastomer resin composition (Y) covering the metal member (Z) is preferably 0.01 to 2.0 mm, more preferably 0.02 to 1.0 mm. If the thickness is thinner than 0.01 mm, the residual stress caused by the molding of the thermoplastic resin (X) is not sufficiently relieved, and the thermoplastic resin (X) may crack. Furthermore, when the thermoplastic elastomer resin composition (Y) is injection molded to cover the metal member (Z), it may not be sufficiently molded and may become unfilled, which is not preferable. Also, if the thickness exceeds 2.0 mm, the thermoplastic elastomer resin composition (Y) melts due to the heat and injection pressure of the molten resin when molding the thermoplastic resin (X), which adversely affects the moldability of the thermoplastic resin (X) and causes a decrease in the material properties, which is not preferable.

[0047] The thermoplastic resin composite molded article of the present invention is an airtight molded article in which the metal member (Z) and the thermoplastic resin composition (X) are bonded to each other by a heat treatment with the thermoplastic elastomer resin composition (Y), forming an integrated composite.

[0048] The thermoplastic resin composite molded article of the present invention is produced by inserting an integrated molded article in which the surface of a metal member (Z) is coated with a thermoplastic elastomer resin composition (Y) into an injection mold and then injection molding the thermoplastic resin. In the injection molding, the thermoplastic elastomer resin composition (Y) is melted by the heat of the molten resin during molding of the thermoplastic resin composition (X) and the injection pressure, forming a molten layer, thereby bonding the two. In addition, the thermoplastic elastomer (Y) can be melted and bonded to the metal member (Z) by the heat of the molten resin during molding of the thermoplastic resin (X), but if the bonding is insufficient and long-term cold and hot treatment is performed, leakage may occur. Therefore, after manufacturing a thermoplastic resin composite molded body, it is possible to bond the metal member (Z) and the thermoplastic elastomer resin composition (Y) more strongly by performing a heat treatment, and it is possible to obtain stable airtightness even after long-term environmental treatment. Examples of environmental treatment include cold and hot treatment, dry heat treatment, wet heat treatment, immersion in automatic transmission fluid (hereinafter ATF), and immersion in long-life coolant. For example, a method of placing a molded body in an oven at a temperature of +21°C to +50°C of the melting point of the thermoplastic elastomer resin composition (Y) and performing heat treatment can be mentioned. If the temperature of the heat treatment is low, the bonding between the metal member (Z) and the thermoplastic elastomer resin composition (Y) is insufficient, and if long-term environmental treatment is performed, leakage may occur. In addition, if the heat treatment temperature is too high, the thermoplastic elastomer resin composition is deteriorated, which may cause leakage.

[0049] Since the temperature rise time at the interface between the metal component (Z) and the thermoplastic elastomer resin composition (Y) varies depending on the shape of the molded product, the type of metal used, and the type of thermoplastic resin, it is desirable to appropriately consider the treatment temperature and treatment time.

[0050] Examples of applications for the thermoplastic resin composite molded article of the present invention include electrical and electronic components such as sensors, LED lamps, connectors, sockets, resistors, relay cases, switches, coil bobbins, capacitors, variable capacitor cases, oscillators, various terminal boards, transformers, plugs, printed circuit boards, tuners, speakers, microphones, headphones, small motors, magnetic head bases, semiconductors, liquid crystal, FDD carriages, FDD chassis, motor brush holders, parabolic antennas, and computer-related components; VTR components, television components, irons, hair dryers, rice cooker components, microwave oven components, acoustic components, and audio. Home and office electrical appliance parts such as audio equipment parts such as laser discs (registered trademark) and compact discs, lighting parts, refrigerator parts, air conditioner parts, typewriter parts, word processor parts, etc.; office computer related parts, telephone related parts, facsimile related parts, copier related parts, cleaning tools, motor parts, lighters, typewriters, etc.; optical equipment and precision machinery related parts such as microscopes, binoculars, cameras, clocks, etc.; water faucet tops, mixer taps, pump parts, pipe joints, water flow control valves, relief valves, water temperature sensors, water flow sensors, water meter housings, etc.;Valve alternator terminals, alternator connectors, IC regulators, potentiometer bases for light dimmers, various valves such as exhaust gas valves, various pipes for fuel, exhaust system and intake system, air intake nozzle snorkels, intake manifolds, fuel pumps, engine coolant joints, carburetor main bodies, carburetor spacers, exhaust gas sensors, coolant sensors, oil temperature sensors, throttle position sensors, crankshaft position sensors, air flow meters, brake pad wear sensors, thermostat bases for air conditioners, heating hot air flow control valves, brush holders for radiator motors, water pump inlets, etc. Impellers, turbine vanes, wiper motor related parts, distributors, starter switches, starter relays, transmission wire harnesses, windshield washer nozzles, air conditioner panel switch boards, fuel-related electromagnetic valve coils, fuse connectors, horn terminals, electrical component insulation plates, step motor rotors, lamp sockets, lamp reflectors, lamp housings, brake pistons, solenoid bobbins, engine oil filters, battery parts such as lithium-ion batteries, drive motor parts, generator motor parts, electric power steering parts, brake parts, ignition device cases, vehicle speed sensors, cable liners, power modules, fuses and relay switches; Examples of applications include automotive and vehicle related parts such as electrical junction boxes with embedded components and terminal blocks for motor inverters.

[0051] The thermoplastic resin composite molding of the present invention has excellent bonding strength and airtightness, and is therefore suitable for use in electric / electronic component integrated module components and components in which metal is inserted, such as terminal blocks for motors, batteries, and motor inverters, where permeation of liquids such as water vapor, water, and oil must be reduced. EXAMPLES

[0052] The present invention will be described in more detail below with reference to examples. In the following examples, parts and percentages are by mass unless otherwise specified.

[0053] Test examples using the thermoplastic resin composite molded article of the present invention will be described below.

[0054] FIG. 1 is a schematic diagram of the thermoplastic resin composite molded product used in Example 1. FIG. 1(a) shows a metal terminal used in the test, measuring 6 × 70 × 1 mm with a hole of φ1.5 mm in the center. FIG. 1(b) shows a molded product in which the center of a metal terminal is coated with a thermoplastic elastomer resin composition (Y). FIG. 1(c) shows a thermoplastic resin composite molded product obtained by insert molding the metal terminal coated with the thermoplastic elastomer resin composition (Y) with a thermoplastic resin (X).

[0055] FIG. 2 shows a cross-sectional view of the thermoplastic resin composite molded product used in Example 1, in which the thermoplastic elastomer resin composition (Y) is interposed between the thermoplastic resin (X) and the metal terminal.

[0056] FIG. 3 shows the dimensions of the metal terminal and thermoplastic resin composite molding used in Example 1, FIG. 3(d) shows the dimensions of the metal terminal used in Example 1, FIG. 3(e) shows the dimensions of the metal terminal coated with the thermoplastic elastomer resin composition used in Example 1, and FIG. 3(f) shows the dimensions of the thermoplastic resin composite molding used in Example 1.

[0057] [Cold and heat treatment] The thermoplastic resin composite molded body was subjected to a thermal shock test using an Espec Corporation thermal shock tester, Model TSA-41, where one cycle consisted of a 30 minute treatment at 130°C, followed by a 30 minute treatment at -40°C. The leak properties were evaluated at 50 cycles, 300 cycles, 500 cycles, and 1000 cycles.

[0058] [Moist heat treatment] The thermoplastic resin composite molded body thus produced was subjected to a leak test using an Espec Corporation thermohygrostat LHL-114 for 100 hours at a temperature of 80°C and a humidity of 95%rh.

[0059] [Dry heat treatment] The thermoplastic resin composite molded body thus produced was treated at a temperature of 130°C for 500 hours using an incubator GPH-202 manufactured by Espec Corporation, and the leak property was evaluated.

[0060] [ATF immersion treatment] The thermoplastic resin composite molded body thus produced was immersed in e-transaxle fluid TE, an ATF manufactured by ENEOS Corporation, and treated at a temperature of 150°C for 1000 hours to evaluate the leak property.

[0061] [Leakage test] As shown in Figure 4, a thermoplastic resin composite molded product was fixed to a jig for leak testing and placed in a water tank with a tube for introducing compressed air connected to the socket of the jig. Air at a pressure of 0.5 MPa was introduced into the jig from the tube, and air leakage from the gap between the metal member (Z) and the thermoplastic resin (X) was confirmed.

[0062] In the examples, two types of metal terminals were used: one made of an aluminum alloy and one made of copper.

[0063] [Measurement of melting point of thermoplastic elastomer resin composition (Y)] The melting point was measured using a TA Instruments Differential Scanning Calorimeter (DSC) Q100 by heating from room temperature to 240°C at a heating rate of 10°C / min.

[0064] [Compounds used in the examples] Metallic parts (Z) (Z-1) Aluminum (Z-2) Nickel-plated copper (Z-3) Tin-plated copper (Z-4) Chrome-plated copper (Z-5) Copper [Thermoplastic resin (X)] (X-1) Polybutylene terephthalate resin (Toray Industries, Inc. "Trecon" 1101G30) (X-2) Polyphenylene sulfide resin (Toray Industries, Inc. "TORELINA" 495MA2B) (X-3) Polyamide resin (Celanese Corporation "Zytel" HTNFR52G35NHF) [Production of thermoplastic polyester elastomer (Y-1)] The polyester block copolymer (A-1), Hytrel 2401 manufactured by Toray Celanese Co., Ltd., the polyvinyl alcohol resin (B), Eslec BL-1 manufactured by Sekisui Chemical Co., Ltd., the silane coupling agent (C), Z-6040 manufactured by Dow Corning Toray Co., Ltd., and the antioxidant (D), Naugard 445 (aromatic amine-based antioxidant) manufactured by Shiraishi Calcium Co., Ltd., were dry-blended in the proportions shown in Table 1, and the mixture was melt-kneaded at a temperature setting of 220°C using a twin-screw extruder having a 45 mmφ screw, and then pelletized to obtain a thermoplastic elastomer resin composition (Y-1).

[0065] [Production of thermoplastic polyester elastomer (Y-2)] The polyester block copolymer (A-2) manufactured by Toray Celanese Co., Ltd. (Hytrel 2300X06), the polyester block copolymer (A-3) manufactured by Toray Celanese Co., Ltd. (4057N), the polyvinyl alcohol resin (B) manufactured by Sekisui Chemical Co., Ltd. (S-LEC BL-1), the silane coupling agent (C) manufactured by Dow Corning Toray Co., Ltd. (Z-6040), and the antioxidant (D) manufactured by Shiraishi Calcium Co., Ltd. (Naugard 445 (aromatic amine-based antioxidant)) were dry-blended in the mixing ratios shown in Table 1, and the mixture was melt-kneaded at a temperature setting of 220°C using a twin-screw extruder having a 45 mmφ screw, and then pelletized to obtain a thermoplastic elastomer resin composition (Y-2).

[0066] [Production of thermoplastic polyester elastomer (Y-3)] The polyester block copolymer (A-4), Hytrel 2551 manufactured by Toray Celanese Co., Ltd., the polyvinyl alcohol resin (B), Eslec BL-1 manufactured by Sekisui Chemical Co., Ltd., the silane coupling agent (C), Z-6040 manufactured by Dow Corning Toray Co., Ltd., and the antioxidant (D), Naugard 445 (aromatic amine-based antioxidant) manufactured by Shiraishi Calcium Co., Ltd., were dry-blended in the mixing ratios shown in Table 1, and the mixture was melt-kneaded at a temperature setting of 240°C using a twin-screw extruder having a 45 mmφ screw, and then pelletized to obtain a thermoplastic elastomer resin composition (Y-3).

[0067] [Table 1]

[0068] Examples 1 to 12, Comparative Examples 1 to 4 A thermoplastic resin composite molded product as shown in FIG. 1 was produced and its airtightness was evaluated. The metal member (Z) with a size of 6×70×1 mm and a hole of φ1.5 mm in the center shown in FIG. 1(a) was inserted into a mold for molding a molded product in which the thermoplastic elastomer resin composition (Y) covers the metal member (Z), and an in-line screw type injection molding machine (NEX-1000 manufactured by Nissei Plastics Industries) was used to cover the metal terminal with the thermoplastic elastomer resin composition so that the metal terminal had a thickness of 0.4 mm and a length of 6 mm and a shape as shown in FIG. 1(b). Next, the thermoplastic resin (X) was injection molded to obtain a thermoplastic resin composite molded body shown in FIG. 1(c). The thermoplastic resin composite molded body made from the combination of the metal member (Z), the thermoplastic elastomer resin composition (Y), and the thermoplastic resin (X) shown in Table 2 was heat-treated in an oven. Cold heat treatment, moist heat treatment, dry heat treatment, and immersion in ATF were performed as environmental treatments, and a leak test was performed after each environmental treatment. Table 2 shows the materials used, the heat treatment conditions, and the results of the airtightness evaluation.

[0069] [Table 2]

[0070] From the above results, in the thermoplastic resin composite molded bodies shown in Examples 1 to 12, no air leakage was observed even after 500 cycles of cooling and heating. Furthermore, no air leakage was observed even after 1000 cycles.

[0071] On the other hand, in Comparative Example 1 where no heat treatment was performed, no leakage occurred after 50 cycles of cold / hot treatment, but air leakage was confirmed after 100 cycles of treatment. Air leakage was also confirmed in the thermoplastic resin composite molded bodies of Comparative Examples 2 and 3 after 100 cycles of cold / hot treatment.

[0072] The thermoplastic resin composite molded product shown in Example 2 showed no air leakage even after 100 hours of wet heat treatment at a temperature of 80° C. and a humidity of 95% rh. In addition, no air leakage was observed after 500 hours of dry heat treatment at 130° C. Furthermore, no air leakage was observed after 1000 hours of immersion in ATF.

[0073] On the other hand, the thermoplastic resin composite molded product shown in Comparative Example 4, which has the same combination of metal (Z), thermoplastic resin (X), and thermoplastic elastomer resin composition (Y) as in Example 2 but has not been subjected to heat treatment, showed no air leakage after 50 cycles of cold and hot treatment, but air leakage was confirmed after 100 cycles of treatment, as in Comparative Examples 1 to 3. Air leakage was also confirmed after all of the dry heat treatment, wet heat treatment, and ATF immersion treatment. This confirmed that the thermoplastic resin composite molded body that had been heat-treated at a constant temperature maintained stable airtightness even after long-term environmental treatment. [Explanation of symbols]

[0074] 1. Terminals that are metal parts (Z) 2.Through holes 3. Thermoplastic elastomer resin composition (Y) 4.Thermoplastic resin (X) 5. Leakage test measurement fixture 6. Socket section 7. Compressed air inlet pipe

Claims

1. A method for producing a thermoplastic resin composite molded product in which a thermoplastic elastomer resin composition (Y) is interposed between a metal member (Z) and a thermoplastic resin (X) in a shape covering the entire circumference of at least a part of the metal member (Z), the thermoplastic elastomer resin composition (Y) containing a hard segment (a1) composed of a crystalline aromatic polyester unit and a soft segment (a2) composed of an aliphatic polyether unit and / or an aliphatic polyester unit, and containing 66 to 98.98 mass% of a polyester block copolymer (A) having a melting point of less than 210°C, 1 to 30 mass% of a polyvinyl alcohol resin (B), 0.01 to 5.0 mass% of a silane coupling agent (C), and 0.01 to 5.0 mass% of an antioxidant (D); (Step A) a step of inserting a metal member (Z) into a mold for molding a molded article in which the metal member (Z) is covered with the thermoplastic elastomer resin composition (Y), and injection-molding the thermoplastic elastomer resin composition (Y) into the mold to cover the metal member (Z) with the thermoplastic elastomer resin composition (Y); (Step B) a step of inserting the molded article obtained in (Step A) into a mold for molding, injection-molding a thermoplastic resin (X) into the mold, and covering the molded article in which the thermoplastic elastomer composition (Y) covers the metal member (Z) with the thermoplastic resin (X); (Step C) further comprising a step of subjecting the molded article in which the thermoplastic resin (X) covers the metal member (Z) and the thermoplastic elastomer composition (Y) to a heat treatment at a temperature of a melting point of the thermoplastic elastomer resin composition (Y) + 21°C to a melting point of the thermoplastic elastomer resin composition (Y) + 50°C.

2. The method for producing a thermoplastic resin composite molded product according to claim 1, wherein the hard segment (a1) composed of a crystalline aromatic polyester unit of the thermoplastic elastomer resin composition (Y) is composed of a polybutylene terephthalate unit derived from terephthalic acid and / or dimethyl terephthalate and 1,4-butanediol, and a polybutylene isophthalate unit derived from isophthalic acid and / or dimethyl isophthalate and 1,4-butanediol.

3. 2. The method for producing a thermoplastic resin composite molding according to claim 1, wherein the thermoplastic resin (X) is mainly composed of at least one resin selected from the group consisting of polyphenylene sulfide resin, polyethylene terephthalate resin, polybutylene terephthalate resin, polycarbonate resin, liquid crystal polyester resin, and polyamide resin.

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