JP2005179425A - Powder for powder molding and powder compact - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a powder for powder molding excellent in powder fluidity and releasability and a powder molded body formed by powder molding the powder.
A powder for powder molding comprising 0.1 to 10 parts by weight of the following component (II) and 0.05 to 1 part by weight of the component (III) per 100 parts by weight of the following component (I).
Component (I): heat having an average particle size of 30 to 1000 μm and a melt flow rate measured at a load of 21.18 N and a temperature of 230 ° C. according to JIS K-7210 (1976) of 10 to 200 g / 10 minutes Plastic elastomer powder Component (II): Thermosetting resin fine powder having an average particle size of 0.005 to 10 μm Component (III): Inorganic fine powder having an average particle size of 0.005 to 0.8 μm Figure] None

Description

  The present invention relates to a powder for powder molding and a powder molded body. More particularly, the present invention relates to a powder for powder molding excellent in powder flowability and powder releasability when the molded product is taken out from the mold after powder molding, and a molded body obtained by powder molding the powder. .

  Skin materials such as automobile interior parts are required to have a complex uneven pattern such as skin marks and stitches on the surface, and to have excellent flexibility, and powder moldings are mainly used for the skin materials. It has been. As the powder molding powder used for molding the powder molded body, for example, thermoplastic elastomer powder made of a composition obtained by dynamically crosslinking oil-extended ethylene-propylene-ethylidene norbornene rubber and polypropylene resin is known. (For example, refer to Patent Document 1). Also known is a powder in which aluminum oxide powder is blended with the thermoplastic elastomer powder (see, for example, Patent Document 2 and Patent Document 3).

JP-A-5-5050 Japanese Patent Laid-Open No. 5-70601 JP-A-11-286578

  However, when powder molding is performed using the above powder, the mold release force when the powder molded body is released from the mold may increase, which is not satisfactory.

  Under such circumstances, the problems to be solved by the present invention include powder molding powder excellent in powder flowability and releasability, appearance of molded product and mechanical strength of molded product, and powder molding of the powder. An object of the present invention is to provide a powder compact.

That is, the first aspect of the present invention is a powder molding powder comprising 0.1 to 10 parts by weight of the following component (II) and 0.05 to 1 part by weight of the component (III) per 100 parts by weight of the following component (I). It is concerned.
Component (I): heat having an average particle size of 30 to 1000 μm and a melt flow rate measured at a load of 21.18 N and a temperature of 230 ° C. according to JIS K-7210 (1976) of 10 to 200 g / 10 minutes Plastic elastomer powder Component (II): Thermosetting resin fine powder having an average particle size of 0.005 to 10 μm Component (III): Inorganic fine powder having an average particle size of 0.005 to 0.8 μm The second of the present invention relates to a powder molded body obtained by powder molding the above powder for powder molding.

  According to the present invention, it is possible to provide a powder for powder molding excellent in powder fluidity and releasability and a powder molded body obtained by powder molding the powder. A powder compact formed by powder molding the powder is excellent in mechanical strength, flexibility, heat resistance and cold shock resistance, and can be excellent in bending whitening resistance, light resistance and the like. Therefore, the powder compact is used for automobile interior parts such as instrument panels, door trims, console boxes, pillars, and the like.

  The thermoplastic elastomer powder used in the component (I) of the present invention is a powder containing a thermoplastic elastomer. Examples of the thermoplastic elastomer include olefin-based thermoplastic elastomers, styrene-based thermoplastic elastomers, polyurethane-based thermoplastic elastomers, polyvinyl chloride-based thermoplastic elastomers, polyamide-based thermoplastic elastomers (for example, Shoji Matsuzaki Chemical) Kogyo Nippo Publishing Co., Ltd., published in 1991, “Thermoplastic Elastomer Composition”). These may be used alone or in combination of two or more.

  Here, examples of the olefin thermoplastic elastomer include a composition comprising a polyolefin resin and a polyolefin rubber. The olefin-based thermoplastic elastomer is produced by a method described in, for example, JP-A-5-5050, JP-A-10-30036, JP-A-10-231392, JP-A-2001-49052, and the like. be able to.

  The polyolefin-based resin is a polymer containing 50% by weight or more of a repeating unit derived from one or more olefins having 2 to 10 carbon atoms such as ethylene, propylene, 1-butene and 1-hexene. And it is a polymer whose A hardness of JIS K-6253 (1997) exceeds 98. The polyolefin resin may contain a repeating unit derived from a monomer other than olefin. Examples of the monomer other than olefin include 1,3-butadiene and 2-methyl-1,3-butadiene. (Isoprene), 1,3-pentadiene, conjugated dienes having 4 to 8 carbon atoms such as 2,3-dimethyl-1,3-butadiene; dicyclopentadiene, 5-ethylidene-2-norbornene, 1,4-hexadiene, Non-conjugated dienes having 5 to 15 carbon atoms such as 1,5-dicyclooctadiene, 7-methyl-1,6-octadiene and 5-vinyl-2-norbornene; Vinyl ester compounds such as vinyl acetate; Methyl acrylate , Unsaturated carboxylic acid esters such as ethyl acrylate, butyl acrylate, methyl methacrylate, ethyl methacrylate; Le acid, and the like unsaturated carboxylic acids such as methacrylic acid.

  Examples of polyolefin resins include ethylene homopolymer, propylene homopolymer, 1-butene homopolymer, ethylene-propylene copolymer, ethylene-1-butene copolymer, ethylene-1-hexene copolymer, Ethylene-1-octene copolymer, propylene-1-butene copolymer, propylene-1-hexene copolymer, propylene-1-octene copolymer, ethylene-propylene-1-butene copolymer, ethylene-propylene Examples include -1-hexene copolymer and ethylene-propylene-1-octene copolymer. These polyolefin resins are used alone or in combination of two or more.

  Among the polyolefin resins, a polypropylene resin in which the content of repeating units derived from propylene is 80% by weight or more is preferably used from the viewpoint of heat resistance of the obtained powder molded body. The content of the repeating unit derived from propylene in the polypropylene resin is more preferably 90% by weight or more, and still more preferably 95% by weight or more.

  The melt flow rate (MFR) of the polyolefin resin is preferably 10 to 500 g / 10 minutes from the viewpoint of further improving the meltability of the powder for powder molding, the mechanical strength of the resulting powder molded body, and the wear resistance. More preferably, it is 50-400 g / 10min, More preferably, it is 100-300 g / 10min. The MFR is measured under conditions of a temperature of 230 ° C. and a load of 21.18 N according to JIS K-7210 (1976).

  The above-mentioned polyolefin rubber is derived from one or more olefins having 2 to 10 carbon atoms such as ethylene, propylene, 1-butene, 2-methylpropylene, 3-methyl-1-butene and 1-hexene. It is a polymer containing 50% by weight or more of the repeating units, and the A hardness of JIS K-6253 (1997) is 98 or less. The polyolefin rubber may contain a repeating unit derived from a monomer other than olefin. Examples of the monomer other than olefin include 1,3-butadiene and 2-methyl-1,3-butadiene. (Isoprene), 1,3-pentadiene, conjugated dienes having 4 to 8 carbon atoms such as 2,3-dimethyl-1,3-butadiene; dicyclopentadiene, 5-ethylidene-2-norbornene, 1,4-hexadiene, Non-conjugated dienes having 5 to 15 carbon atoms such as 1,5-dicyclooctadiene, 7-methyl-1,6-octadiene and 5-vinyl-2-norbornene; Vinyl ester compounds such as vinyl acetate; Methyl acrylate , Unsaturated carboxylic acid esters such as ethyl acrylate, butyl acrylate, methyl methacrylate, ethyl methacrylate; Le acid, and the like unsaturated carboxylic acids such as methacrylic acid.

  Examples of polyolefin rubbers include propylene homopolymer, 1-butene homopolymer, 2-methylpropane homopolymer, ethylene-propylene copolymer, ethylene-1-butene copolymer, ethylene-3-methyl- 1-butene copolymer, ethylene-1-hexene copolymer, ethylene-1-octene copolymer, propylene-1-butene copolymer, propylene-1-hexene copolymer, propylene-1-octene copolymer A copolymer, an ethylene-propylene-5-ethylidene-2-norbornene copolymer, an ethylene-propylene-1-butene copolymer, an ethylene-propylene-1-hexene copolymer, and an ethylene-propylene-1-octene copolymer. These polyolefin rubbers are used alone or in combination of two or more. These can be produced by known methods.

  Among polyolefin-based rubbers, ethylene-α-olefin copolymer rubber is preferably used from the viewpoint of further increasing the mechanical strength of the molded body. Here, as the α-olefin, propylene, 1-butene, 1-hexene and 1-octene are preferable from the viewpoint of availability.

  Among the polyolefin-based rubbers, an ethylene-α-olefin copolymer rubber having an A hardness of JIS K-6253 (1997) of 80 or less is preferable from the viewpoint of further improving the flexibility of the molded body (requirement (1)). . When the hardness exceeds 80, the mechanical strength and flexibility of the obtained powder compact may be inferior.

  The melt flow rate (MFR) of the polyolefin rubber is preferably 0.5 to 50 g / 10 min from the viewpoint of further improving the meltability of the powder for powder molding, the mechanical strength of the molded body, and the wear resistance. More preferably, it is 1-30 g / 10min. In addition, MFR is measured on condition of temperature 190 degreeC and load 21.18N according to JISK-7210 (1976).

  The content of the polyolefin resin and polyolefin rubber in the olefin thermoplastic elastomer is usually 20 to 300 parts by weight with respect to 100 parts by weight of the polyolefin resin, but the flexibility, heat resistance and cold resistance of the obtained powder molded body From the viewpoint of impact properties, it is preferably 25 to 150 parts by weight.

  When the thermoplastic elastomer powder contains a polyolefin resin and an ethylene-α-olefin copolymer rubber, the mechanical strength of the powder molded product can be improved by further containing a hydrogenated conjugated diene polymer.

  As the hydrogenated conjugated diene polymer, for example, a raw material which is one or more polymers having 4 to 8 carbon atoms such as 1,3-butadiene, isoprene, pentadiene, 2-3-dimethylbutadiene and the like. Examples thereof include hydrogenated conjugated diene polymers, such as hydrogenated polybutadiene and hydrogenated polyisoprene. By hydrogenating the raw material conjugated diene polymer, the unsaturated bond of the conjugated diene unit is saturated. When the saturated monomer unit is a hydrogenated conjugated diene unit, a hydrogenated conjugated diene polymer is used. From the viewpoint of flexibility of the obtained powder compact, the content of hydrogenated conjugated diene units having 2 or more carbon atoms in the side chain is preferably more than 50% by weight. However, the content of hydrogenated conjugated diene units in the hydrogenated conjugated diene polymer is 100% by weight. The hydrogenated conjugated diene polymer may be composed of two or more blocks having different proportions of hydrogenated conjugated diene units having 2 or more carbon atoms in the side chain. Examples of such a hydrogenated conjugated diene polymer include a polymer described in JP-A-3-74409, a commercially available product such as “Dynalon CEBC6200” manufactured by JSR Corporation.

  In the case of containing a hydrogenated conjugated diene polymer, the content is 100 parts by weight of the total amount of polyolefin resin and ethylene-α-olefin copolymer rubber from the viewpoint of the tensile strength and flexibility of the obtained powder molded body. On the other hand, it is preferably 1 to 20 parts by weight, more preferably 2 to 10 parts by weight.

  Styrenic thermoplastic elastomer is a vinyl aromatic compound-conjugated diene copolymer or a hydrogenated product thereof.

  As the vinyl aromatic compound used in the styrene-based thermoplastic elastomer, for example, a vinyl aromatic compound having 8 to 12 carbon atoms is used, and the 1- or 2-position of the vinyl group is an alkyl group such as a methyl group. It may be substituted, and specifically includes styrene, p-methylstyrene, α-methylstyrene and the like, and these are used alone or in combination of two or more. Among these, styrene is preferable from the viewpoint of further increasing the mechanical strength of the obtained powder compact.

  As the conjugated diene, for example, a conjugated diene having 4 to 8 carbon atoms is used, and examples thereof include 1,3-butadiene, isoprene, pentadiene, 2-3-dimethylbutadiene, and the like. Used in combination. Among these, 1,3-butadiene and / or isoprene are preferable from the viewpoint of further increasing the mechanical strength of the obtained powder compact.

  Examples of the vinyl aromatic compound-conjugated diene copolymer include styrene-1,3-butadiene copolymer and styrene-isoprene copolymer, and these are used alone or in combination of two or more. Moreover, these can be manufactured by a well-known method.

  The vinyl aromatic compound-conjugated diene copolymer may be composed of one block or may be composed of two or more blocks having different structures. Examples of the structure composed of one block include a copolymer having a structure in which vinyl aromatic compounds and conjugated dienes are randomly arranged, for example, a styrene-butadiene random copolymer and a styrene-isoprene random copolymer. . As what is comprised from two or more blocks from which a structure differs, it is comprised from the copolymer comprised from a styrene homopolymer block-butadiene homopolymer, a styrene homopolymer block-isoprene homopolymer block, for example Copolymer, styrene homopolymer block-butadiene homopolymer block-copolymer composed of styrene homopolymer block, styrene homopolymer block-isoprene homopolymer block-styrene homopolymer block Copolymer, copolymer composed of styrene homopolymer block-butadiene-isoprene copolymer block-styrene homopolymer block, styrene homopolymer block-styrene-butadiene copolymer block-styrene homopolymer block Copolymer composed of In such a copolymer, the styrene-butadiene copolymer block may be a block having a structure in which styrene and butadiene are randomly copolymerized, or a taper in which the content of styrene units gradually decreases or increases. It may be a block having a shape structure.

  The vinyl aromatic compound-conjugated diene copolymer hydrogenated product is a polymer obtained by hydrogenating the above-mentioned vinyl aromatic compound-conjugated diene copolymer. Similar to the combination, the structure may be composed of one block, or may be composed of two or more blocks having different structures. Examples of hydrogenated products of vinyl aromatic compounds and conjugated diene copolymers include styrene-1,3-butadiene copolymer hydrogenated products and styrene-isoprene copolymer hydrogenated products. Used in combination of two or more species.

  The melt flow rate (MFR) measured at 230 ° C. under a load of 21.18 N in accordance with JIS K-7210 of styrene thermoplastic elastomer is the mechanical strength, abrasion resistance, and powder for powder molding obtained. From the viewpoint of further improving the meltability of the resin, it is preferably 1 to 200 g / 10 minutes, more preferably 2 to 100 g / 10 minutes, and further preferably 3 to 80 g / 10 minutes.

  The styrenic thermoplastic elastomer may be modified with a functional group, and the functional group is at least one functional group selected from an acid anhydride group, a carboxyl group, a hydroxyl group, an amino group, an isocyanate group, and an epoxy group. Can be used. When a styrenic thermoplastic elastomer modified with these functional groups is used, for example, when coating is performed on the surface of the obtained powder molded body, adhesion to the coating film may be improved.

  Among the styrenic thermoplastic elastomers, a hydrogenated vinyl aromatic compound-conjugated diene copolymer that satisfies the following requirement (2) is preferable from the viewpoint of mechanical strength of the obtained powder molded body.

(2): hydrogenated vinyl aromatic compound-conjugated diene copolymer containing structural units of the following (a) and (b): (a): vinyl aromatic compound polymer block (b): At least one block selected from the following (b1) and (b2) (b1): a copolymer block of a vinyl aromatic compound and a conjugated diene (b2): a conjugated diene polymer block The above requirement (2) is satisfied The hydrogenated vinyl aromatic compound-conjugated diene copolymer has the general formula [(a)-(b)] n, [(a)-(b)] n- (a), [(b)-(a )] N- (b) (where n is an integer greater than or equal to 1 and when (a) and (b) are plural, the plural (a) and (b) are the same or different. For example, [(a)-(b1)] n- (a), [ a) - (b2)] which is represented by n-(a) and the like.

  Among the hydrogenated vinyl aromatic compound-conjugated diene copolymer hydrogenated products satisfying the above requirement (2), (a)-(b1)-(a) from the viewpoint of mechanical strength of the obtained powder molded body , (A)-(b2)-(a), a vinyl aromatic compound-conjugated diene copolymer hydrogenated product is preferable. For example, a styrene homopolymer block-butadiene-styrene copolymer block (random copolymer block) Or a tapered block in which styrene gradually increases)-a hydrogenated polymer composed of a styrene homopolymer block, a styrene homopolymer block-a butadiene homopolymer block-a polymer composed of a styrene homopolymer block Hydrogenated product, styrene homopolymer block-isoprene-styrene copolymer block (random copolymer block -Like block) -hydrogenated polymer composed of styrene homopolymer block, styrene homopolymer block-isoprene homopolymer block-hydrogenated polymer composed of styrene homopolymer block, and the like. Among these, a hydrogenated vinyl aromatic compound-conjugated diene copolymer represented by (a)-(b2)-(a) is more preferable, and a styrene-butadiene-styrene copolymer hydrogenated product is more preferable. Is particularly preferred.

The total vinyl aromatic compound unit content (T: wt%) of the styrenic thermoplastic elastomer is sufficient for the flexibility, bending whitening resistance and heat resistance (prevention of the molding surface and prevention of bleeding) of the obtained powder molding. From the viewpoint, it is preferably 10 to 18% by weight (requirement (3)), and more preferably 12 to 17% by weight. However, the content of all monomer units contained in the styrene thermoplastic elastomer is 100% by weight. The total vinyl aromatic compound unit content can be determined by ¹ H-NMR measurement using a solution of the styrene-based thermoplastic elastomer such as carbon tetrachloride.

  As the styrenic thermoplastic elastomer, from the viewpoint of flexibility, bending whitening resistance, and light resistance of the obtained powder molded body, inclusion of a hydrogenated conjugated diene unit in the hydrogenated vinyl aromatic compound-conjugated diene copolymer Hydrogenation of vinyl aromatic compound-conjugated diene copolymer in which the content of hydrogenated conjugated diene units having 2 or more carbon atoms in the side chain (V: wt%) exceeds 60 wt% with respect to the amount of 100 wt% (Requirement (4)), a vinyl aromatic compound-conjugated diene copolymer hydrogenated product in which the content of hydrogenated conjugated diene units having 2 or more carbon atoms in the side chain is 65 to 85% by weight More preferred is a hydrogenated vinyl aromatic compound-conjugated diene copolymer hydrogenated product having a content of hydrogenated conjugated diene units having 2 or more carbon atoms in the side chain of 70 to 80% by weight. The unsaturated bond of the conjugated diene unit is saturated by hydrogenating the vinyl aromatic compound-conjugated diene copolymer. The saturated monomer unit is a hydrogenated conjugated diene unit, and the unit The content of can be determined by the Morero method using infrared analysis.

As a styrenic thermoplastic elastomer, from the viewpoint of heat resistance of the resulting powder molded body (gloss of the surface of the molded body and prevention of bleeding), (a) vinyl aromatic compound unit content in the vinyl aromatic compound polymer block Amount (S:% by weight, where the content of vinyl aromatic compound unit in the styrene-based thermoplastic elastomer is 100% by weight), (T) of requirement (3), (V) of requirement (4) It is preferable that the relationship satisfies the following formula (1) (requirement (5)).
V ≦ 0.375 × S + 1.25 × T + 40 (1)
Among these, when a styrenic thermoplastic elastomer satisfying the above requirements (2) to (5) is used, mechanical strength, flexibility, bending whitening resistance, heat resistance (gloss on the surface of the molded body and bleed material) Prevention) and a powder compact excellent in light resistance can be obtained.

  Styrenic thermoplastic elastomers satisfying the requirements (2) to (5) are disclosed in, for example, JP-A-3-72512, JP-A-5-271325, JP-A-5-271327, and JP-A-6-287365. Can be produced by the method described in the above.

  The styrene thermoplastic elastomer can also be used by containing the polyolefin resin, and the content of the polyolefin resin is usually 500 parts by weight or less with respect to 100 parts by weight of the styrene thermoplastic elastomer. Preferably, it is 50 to 400 parts by weight.

  The polyurethane-based thermoplastic elastomer is a thermoplastic elastomer having polyurethane as a hard segment and polyol or polyester as a soft segment. A stabilizer and a pigment are mix | blended as needed. Examples of the powder made of a polyurethane thermoplastic elastomer include Meltex LA manufactured by Sanyo Chemical Industries, Ltd.

  The polyvinyl chloride thermoplastic elastomer is a thermoplastic elastomer in which a polyvinyl chloride resin, a plasticizer, and, if necessary, a stabilizer and a pigment are blended. As a polyvinyl chloride thermoplastic elastomer, Sumitomo Chemical Co., Ltd. Smilit FLX etc. are mentioned, for example. The vinyl chloride thermoplastic elastomer may further contain a polymer such as NBR (acrylonitrile-butadiene copolymer rubber) or EVA (ethylene-vinyl acetate copolymer rubber). In this case, a powder compact having excellent cold shock resistance can be obtained.

  The polyamide-based thermoplastic elastomer is a block copolymer having a crystalline polyamide having a high melting temperature as a hard segment and a non-crystalline polyether or polyester having a low glass transition temperature as a soft segment. If necessary, pigments and stabilizers are blended. Polyamide thermoplastic elastomers are roughly classified into two types, polyether ester type and polyester amide type. Polyamide thermoplastic elastomers are further classified into NBR (acrylonitrile-butadiene copolymer rubber) and EVA (ethylene-ethylene-type). Polymers such as vinyl acetate copolymer rubber) may be blended. In this case, a powder compact having excellent cold shock resistance can be obtained.

  As the thermoplastic elastomer, from the viewpoint of improving the mechanical strength, bending whitening resistance, heat resistance (gloss of the molded body surface and prevention of bleeding) and light resistance of the obtained powder molded body, an olefin-based thermoplastic elastomer and a styrene system are used. A thermoplastic elastomer containing a thermoplastic elastomer is preferable, and satisfies all of the above requirements (2) to (5) and an olefinic thermoplastic elastomer composed of a polyolefin resin and a polyolefin rubber that satisfies the requirement (1). A thermoplastic elastomer containing a styrenic thermoplastic elastomer is more preferable.

  In this case, the content of the polyolefin-based rubber is preferably 20 to 200 weights with respect to 100 parts by weight of the polyolefin-based resin from the viewpoint of further improving the flexibility, cold shock resistance, heat resistance and light resistance of the obtained powder molded body. Part, more preferably 25 to 150 parts by weight.

  The content of the styrenic thermoplastic elastomer is preferably 20 with respect to 100 parts by weight of the polyolefin resin from the viewpoint of further improving the mechanical strength, bending whitening resistance, heat resistance and light resistance of the obtained powder molded body. It is -300 weight part, More preferably, it is 25-200 weight part.

  The thermoplastic elastomer powder used in the powder molding powder according to the present invention includes, in addition to the above-mentioned thermoplastic elastomer, rubbery heavy materials such as conjugated diene polymer, natural rubber, butyl rubber, chloroprene rubber, epichlorohydrin rubber, and acrylic rubber. Copolymer; ethylene-acrylic acid copolymer, ethylene-vinyl acetate copolymer and saponified products thereof, ethylene-methyl methacrylate copolymer, ethylene-glycidyl acrylate-vinyl acetate copolymer, ethylene-glycidyl methacrylate- It may contain other polymer components such as vinyl acetate copolymer. The content is usually 50 parts by weight or less with respect to 100 parts by weight of the thermoplastic elastomer.

  The thermoplastic elastomer powder used in the powder molding powder of the present invention includes, for example, mineral oil softeners, heat stabilizers such as phenols, sulfites, phenylalkanes, phosphites, amines, amides, Contains weathering stabilizers, antistatic agents, pigments, silicone compounds, metal soaps, paraffinic, microcrystalline, waxes such as hydrogenated terpene resins, various additives such as fungicides, antibacterial agents, fillers, foaming agents, etc. You may do it.

  In particular, when the thermoplastic elastomer powder contains a silicone compound, the peelability can be further improved. The content of the silicone compound is preferably 0.1 parts by weight or more, more preferably 0.5 parts by weight or more from the viewpoint of enhancing the peelability with respect to 100 parts by weight of the thermoplastic elastomer. From the viewpoint of increasing the mechanical strength at a particularly low temperature, it is preferably 10 parts by weight or less, more preferably 7 parts by weight or less.

  When the thermoplastic elastomer powder used for the powder molding powder of the present invention contains a pigment, a powder molded body having a desired color can be obtained. Examples of pigments include organic pigments such as azo, phthalocyanine, selenium, and dyeing lakes, oxides such as titanium oxide, molybdates of chromic acid, selenium sulfide compounds, ferrocyan compounds, and carbon black. Used.

  In order to obtain a polymer composition containing a thermoplastic elastomer used for a thermoplastic elastomer powder, the polymer component constituting the thermoplastic elastomer and, if necessary, other polymer components and / or additives, May be melt-kneaded. Alternatively, all or several kinds of the above components may be selected and kneaded or dynamically crosslinked, and then the components not selected may be melt-kneaded. Here, for melt kneading, known kneading equipment such as a single screw extruder, a twin screw extruder, a kneader, and a roll can be used. The above-mentioned other polymer components and additives can be blended by using the above-described polymer components blended in advance, or blended during kneading or dynamic crosslinking of the above components. You can also.

  The melt flow rate (MFR) of the thermoplastic elastomer powder is 10 to 200 g / 10 minutes, preferably 30 to 100 g / 10 minutes. If the MFR is too low, the meltability of the powder for powder molding may be inferior, and the resulting powder molded body may be thinned, pinholes, etc., resulting in poor mechanical strength or abrasion resistance during powder molding. It may be inferior to wear. Further, if the MFR is too high, the resulting molded article may have poor mechanical strength or may have poor wear resistance. The MFR is measured under conditions of a temperature of 230 ° C. and a load of 21.18 N according to JIS K-7210 (1976).

  The thermoplastic elastomer powder used in the powder molding powder of the present invention includes a method of mechanically pulverizing the polymer composition containing the thermoplastic elastomer, a strand cut method, a die face cut method, a solvent treatment method, etc. It can be manufactured by a method (for example, see JP-A-2001-49052).

  Examples of a method for mechanically pulverizing the polymer composition containing the thermoplastic elastomer include a freeze pulverization method and a room temperature pulverization method. The freeze pulverization method is a method in which the polymer composition is cooled to a glass transition temperature or lower, preferably −70 ° C. or lower, more preferably −90 ° C. or lower, and pulverized while keeping the cooled state. From the viewpoint of making the particle diameter of the thermoplastic elastomer powder more uniform and improving the powder moldability, the freeze pulverization method is preferred.

  The average particle diameter of said thermoplastic elastomer powder is 30-1000 micrometers, Preferably it is 100-600 micrometers, More preferably, it is 200-500 micrometers. If the particle size is too large, it may be difficult to control the thickness of the resulting powder molded body to be thin, or the resulting powder molded body may have a lack of thickness or pinholes, resulting in poor mechanical strength. is there. In addition, if the average particle size is too small, the powder fluidity of the powder for powder molding obtained is reduced, or the resulting powder molded body has poor thickness and pinholes, resulting in poor mechanical strength, May be inferior. The average particle diameter of the thermoplastic elastomer powder is sieved according to JIS R-6002 (1978) using a standard sieve defined in JIS Z-8801 (1976). And plotting the weight fraction of the powder for powder molding that passed through each standard sieve, and based on the cumulative weight fraction line obtained from each plot, the cumulative weight fraction line and the cumulative weight fraction line of 50% by weight It is calculated from the intersection of

  Examples of the thermosetting resin fine powder used for the component (II) of the present invention include melamine resin, benzoguanamine resin, melamine / benzoguanamine copolymer resin, phenol resin, epoxy resin, urea resin, alkyd resin and the like. Among these, melamine resin or benzoguanamine resin is preferably used from the viewpoint of availability.

  The average particle size of the thermosetting resin fine powder is 0.005 to 10 μm, preferably 0.01 to 5 μm. If the particle size is too large, the powder flowability of the obtained powder for powder molding may be lowered or the releasability may be poor. If the particle size is too small, workability may be reduced.

  The average particle diameter of the thermosetting resin fine powder is determined by observing the thermosetting resin fine powder with an electron microscope at a magnification of 1000 to 500,000 times, and arbitrarily selecting the diameter of about 30 fine powders from among them. Measured and obtained from the number average value.

  The blending amount of the thermosetting resin fine powder in the powder for powder molding is 0.1 to 10 parts by weight, preferably 0.3 to 5 parts by weight with respect to 100 parts by weight of the thermoplastic elastomer powder. Preferably it is 0.5-3 weight part. If the blending amount is too small, the powder fluidity may be inferior or the releasability may be inferior. Moreover, when there are too many these compounding quantities, the mechanical strength of the obtained powder compact may be inferior, and the meltability at the time of powder molding may be inferior.

  Examples of the inorganic fine powder used for the component (III) of the present invention include silica, alumina, alumina silica, calcium hydroxide, calcium carbonate, titanium oxide, and metal sulfate. Among these, silica is preferably used from the viewpoint of the appearance of the powder compact.

  The average particle size of the inorganic fine powder used for component (III) is preferably 0.005 to 0.8 μm, more preferably 0.01 to 0.5 μm, from the viewpoint of enhancing the appearance of the powder compact. is there.

  The blending amount of component (III) in the powder molding powder is preferably from 100 parts by weight of the thermoplastic elastomer powder from the viewpoint of increasing the appearance of the powder molding powder powder molding powder and the mechanical strength of the powder molding powder. Is 0.05 to 1 part by weight, more preferably 0.1 to 0.8 part by weight, still more preferably 0.1 to 0.5 part by weight.

The powder molding powder of the present invention may be dry blended with the following component (IV).
Ingredient (IV): Inorganic fine powder having an average particle size of 1 to 10 μm As inorganic substances used in the inorganic fine powder of ingredient (IV), silica, alumina, alumina silica, calcium hydroxide, calcium carbonate, titanium oxide And sulfate metal salts.

  The average particle size of the inorganic fine powder used for component (IV) is preferably 1 to 10 μm, more preferably 2 to 5 μm, from the viewpoint of improving the powder flowability and workability of the powder for powder molding. .

  The blending amount of component (IV) in the powder molding powder is based on 100 parts by weight of the thermoplastic elastomer powder from the viewpoint of increasing the powder fluidity and workability of the powder molding powder and the mechanical strength of the powder molded body. Preferably it is 0.1-10 weight part, More preferably, it is 0.2-5 weight part, More preferably, it is 0.5-3 weight part.

  The average particle size of the thermosetting resin fine powder of component (II) and the thermoplastic resin fine powder of component (III) and component (IV) was measured with an electron microscope at a magnification of 2000 to 500,000 times. The diameters of about 30 fine powders are arbitrarily measured from these, and the number average value is obtained.

  As a method of blending the thermosetting resin fine powder of component (II) and the inorganic fine powder of component (III) and component (IV) with the thermoplastic elastomer powder of component (I), component (I) There is no particular limitation as long as it is a method in which component (IV) is uniformly mixed. For example, a blending method using a blender with a jacket, a high-speed rotating mixer, a nauter mixer, a universal mixer, or the like can be used. Among them, the method of blending using a Henschel mixer or a super mixer is preferred because it is a method of preventing the powder from adhering to each other by applying a shearing force and uniformly dispersing the powder. The blending is usually performed at room temperature.

  The powder for powder molding of the present invention can be applied to various powder molding methods such as a powder slush molding method, fluidized immersion method, electrostatic coating method, powder spraying method, powder rotation molding method, etc. Suitable for the method.

  For example, in the powder slush molding method, it is manufactured by a method comprising the following first to fifth steps.

1st process: The process of supplying the powder for powder molding on the molding surface of the metal mold | die heated more than the melting temperature of a thermoplastic elastomer Usually, metal mold | die temperature is 160-320 degreeC, The heating method of a metal mold | die is A gas heating furnace method, a heat medium oil circulation method, a dipping method in heat medium oil or heat fluidized sand, a high frequency induction heating method, or the like is used.

Second step: A step of heating the powder molding powder on the molding surface of the first step for a predetermined time, and fusing the powders whose surfaces are melted to each other. Third step: After a predetermined time has elapsed in the second step, Step of recovering powder molding powder that has not been fused Fourth step: If necessary, a step of further heating the mold on which the melted powder molding powder is placed Fifth step: After the fourth step, The process of cooling the mold and removing the molded body formed on the mold from the mold

  Further, in order to further improve the demolding property, before heating the mold above the melting temperature of the thermoplastic elastomer in the first step, a fluorine-based and / or silicone-based mold release is performed on the molding surface of the mold. An agent may be coated. Examples of the fluorine-based spray include Daifree GA-6010 (diluted organic solvent) and ME-413 (water-diluted product) manufactured by Daikin, and examples of silicone spray include KF96SP (organic solvent diluted) manufactured by Shin-Etsu Silicone. Product), Frelease 8

  The powder molded body of the present invention may be used as a single-layer molded body, or may be used as a multilayer molded body in which other layers are laminated on one side and / or both sides of the molded body. Examples of the other layer include a synthetic resin layer and a metal layer. Examples of the synthetic resin constituting the synthetic resin layer include polyolefin resins such as polypropylene and polyethylene, thermoplastic elastomers, polyamide resins, and ethylene-vinyl. Examples thereof include alcohol copolymers, polyester resins, ABS (acrylonitrile-butadiene-styrene copolymers), and adhesive resins. These layers may be foamed.

  Moreover, the molded object of this invention can be optimally used for automotive interior parts, such as an instrument panel, a door trim, a console box, a pillar, etc., for example.

Hereinafter, the present invention will be described in detail with reference to examples.
First, various evaluation methods and raw materials in the present invention will be described.
[1] Evaluation method (1) Melt flow rate (MFR)
According to JIS K-7210 (1976), the load was 21.18N and the temperature was 230 ° C.
(2) A hardness Measured according to JIS K-6253 (1997).
(3) Content of vinyl aromatic compound unit in hydrogenated vinyl aromatic compound-conjugated diene copolymer (T: wt%)
It calculated | required from the < ¹ > H-NMR measuring method (frequency 90MHz) using the carbon tetrachloride solution of the vinyl aromatic compound-conjugated diene copolymer hydrogenated material.
(4) (a) Content of vinyl aromatic compound unit in vinyl aromatic compound polymer block (S: wt%)
It calculated | required from the < ¹ > H-NMR measuring method (frequency 90MHz) using the carbon tetrachloride solution of the vinyl aromatic compound-conjugated diene copolymer hydrogenated material.

(5) Content of hydrogenated conjugated diene unit having 2 or more carbon atoms in the side chain (V: wt%) Obtained by the Morello method using infrared analysis.
(6) Hydrogenation rate of vinyl aromatic compound-conjugated diene copolymer hydrogenated material Raw material vinyl aromatic compound-conjugated diene copolymer carbon tetrachloride solution, vinyl aromatic compound-conjugated diene copolymer hydrogenated product Using a carbon tetrachloride solution, a ¹ H-NMR measurement method (frequency: 90 MHz) was used.
(7) Average particle diameter of thermoplastic elastomer powder Using a standard sieve (inner diameter 200 mm) having openings of 500 μm, 355 μm, 250 μm, 212 μm, 180 μm, 150 μm and 106 μm as defined in JIS Z-8801 (1976) In accordance with JIS R-6002 (1978), standard sieves are stacked on a tray in ascending order of opening, and then 100 g of powder forming powder is put on a standard sieve having an opening of 500 μm, and a sieve shaker (Iida And shaken at a frequency of 165 Hz and an amplitude of 1.2 cm for 15 minutes.
The aperture value of each standard sieve is on the X axis (unit: μm), and the weight fraction of the powder for powder molding that has passed through the standard sieve of the aperture (standard sieve and saucer below the standard sieve of the aperture) The weight fraction of the powder for powder molding in (unit:% by weight) was plotted on the Y axis, and a cumulative weight fraction line was created from each plot. Next, the intersection of the cumulative weight fraction line and the cumulative weight fraction 50 wt% line (Y = 50 wt% line) was determined, and the X-axis value of the intersection was taken as the average particle size of the powder for powder molding. In addition, about the weight fraction of the powder for powder shaping | molding, the total amount of the sieved sample was 100 weight%.
(8) Average particle diameter of thermosetting resin fine powder The thermosetting resin fine powder was observed with an electron microscope at a magnification of 50000 times, and about 30 thermosetting resin fine powders were arbitrarily selected therefrom. The diameter was measured, and the number average value was obtained.
(9) Average particle diameter of the inorganic fine powder The fine powder used in the present invention was observed with an electron microscope at a magnification of 5000 to 30000 times, and the diameter of 30 powders was arbitrarily measured from among them. It calculated | required from the number average value.

(10) Powder flowability of powder molding powder After 100 cm ³ of powder molding powder is put into the funnel of the bulk density measuring device described in JIS K-6722 (1977), the damper is opened and all powder is The time to exit the funnel was measured.
(11) Releasability of Powder Slush Molded Body An end of a powder slush molded sheet molded on a mold (15 cm × 30 cm flat plate) was peeled off from the outer periphery of the mold with a width of 1 cm. Attach a spring gauge with a clip to one side (15 cm width side) of the slash sheet peeled off from the end, release the powder slash sheet from the mold while pulling the spring gauge, and release the load indicated by the spring gauge. Evaluated as mold power.
(12) Low temperature tensile test of powder slush molded body According to JIS K-7113 (1981), the low temperature tensile rupture strength and low temperature tensile rupture elongation of the powder slush molded body were measured.
Test piece shape: No. 3 test piece Test temperature: -20 ° C
Tensile speed: 200 mm / min (13) Appearance of powder slush compact The surface of the powder slush compact was visually observed.
○: No pinhole ×: Pinhole

[2] Raw material (1) Thermoplastic elastomer (i) Polyolefin resin Propylene-ethylene random copolymer resin: PPD200 manufactured by Sumitomo Chemical Co., Ltd. (ethylene unit content 5% by weight, MFR = 215 g / 10 min)
(ii) Ethylene-α-olefin copolymer Ethylene-butene copolymer: Exelen FX CX5501 manufactured by Sumitomo Chemical Co., Ltd. (MFR = 31 g / 10 min (however, measured at a load of 21.18 N and a temperature of 190 ° C.)) A hardness 71)
(iii) Hydrogenated compound of vinyl aromatic compound-conjugated diene copolymer Hydrogenated product of styrene-butadiene-styrene block copolymer (total styrene unit content 15% by weight, vinyl aromatic in vinyl aromatic compound polymer block Group compound unit content 100 weight, side chain carbon number of 2 or more hydrogenated conjugated diene unit content 80 weight%, conjugated diene unit double bond hydrogenation rate 98%)
(2) Additives Hydrogenated terpene resin: Clearon P135 manufactured by Yasuhara Chemical Co., Ltd.
Antioxidant: IRGANOX 1076 manufactured by Ciba Specialty Chemicals Co., Ltd.
Silicone: BY27-001 manufactured by Toray Dow Corning Silicone Co., Ltd.
Lubricant: Neutron S (erucic acid amide) manufactured by Nippon Seika Co., Ltd.
Pigment: Gray color pigment Gray PPM8Y1853 made by Sumika Color Co., Ltd.
(3) Thermosetting resin fine powder Melamine resin: Nippon Shokubai Co., Ltd. Eposter S (average particle size 0.2 μm)
(4) Fine inorganic powder silica: OX50 (average particle size 50 nm) manufactured by Nippon Aerosil Co., Ltd.
Alumina silica: JC30 (average particle size 3 μm) manufactured by Mizusawa Chemical Co., Ltd.

Example 1
[Production of thermoplastic elastomer powder]
6. 100 parts by weight of propylene-ethylene random copolymer resin, 96 parts by weight of ethylene-butene copolymer, 156 parts by weight of hydrogenated styrene-butadiene-styrene block copolymer, 19 parts by weight of hydrogenated terpene resin, silicone 4 parts by weight, antioxidant 2.2 parts by weight, lubricant 0.7 parts by weight, pigment 11 parts by weight using a twin-screw kneader (manufactured by Nippon Steel Co., Ltd., TEX-44HCT) A thermoplastic elastomer was prepared by kneading at 150 ° C., and this was cut with a cutting machine into pellets. The melt flow rate (MFR) of the thermoplastic elastomer was 68 g / 10 minutes.
The pellet was cooled to −100 ° C. with liquid nitrogen, pulverized while keeping the cooled state, and the pulverized product was sieved with a Tyler standard sieve (aperture 600 μm × 600 μm) to obtain a thermoplastic elastomer powder. The average particle size of the powder was 228 μm.

[Manufacture of powder for powder molding]
Next, 100 parts by weight of this thermoplastic elastomer powder, 0.8 parts by weight of thermosetting resin fine powder (Epester S manufactured by Nippon Shokubai Co., Ltd.), fine silica powder (OX50 manufactured by Nihon Aerosil Co., Ltd.) (Particle size 50 nm)) 0.2 parts by weight and 1 part by weight of alumina silica fine powder (Mizusawa Chemical Industry Co., Ltd. JC30 (average particle size 3 μm)) And dry blended to obtain a powder for powder molding. Table 1 shows the evaluation results of the powder flowability of the obtained powder for powder molding.

[Production of powder compact by powder slush molding method]
A nickel mold (15 cm x 30 cm x 3 mm thick) with a satin pattern on the surface is heated in an oven heated to 340 ° C for 15 minutes, the mold is taken out from the oven, and the surface temperature of the mold is 280 ° C. At that time, 800 g of the powder molding powder was sprinkled on the molding surface (surface having a satin pattern) of the mold, the powder molding powder was melted, and the powders were fused together. After 13 seconds, the powder for powder molding that was not fused was removed. Thereafter, the mold was further placed in an oven heated to 260 ° C. for 60 seconds. After 60 seconds, the mold was taken out of the oven, cooled with water so that the mold temperature was about 30 ° C., and the releasability was evaluated. Evaluation of releasability was performed 3 times, and the average value is shown in Table 1.

Example 2
0.6 parts by weight of dry blend amount of thermosetting resin fine powder (Epester S manufactured by Nippon Shokubai Co., Ltd.), silica fine powder (OX50 (average particle size 50 nm) manufactured by Nihon Aerosil Co., Ltd.) The same operation as in Example 1 was performed except that the dry blend amount was 0.4 parts by weight. The evaluation results are shown in Table 1.

Example 3
0.4 parts by weight of dry blend amount of thermosetting resin fine powder (Epester S, manufactured by Nippon Shokubai Co., Ltd.), silica fine powder (OX50 (average particle size 50 nm), manufactured by Nihon Aerosil Co., Ltd.) The same operation as in Example 1 was performed except that the dry blend amount was 0.6 parts by weight. The evaluation results are shown in Table 1.

Comparative Example 1
It was carried out in the same manner as in Example 1 except that 1 part by weight of thermosetting resin fine powder (Epester S manufactured by Nippon Shokubai Co., Ltd.) was used and silica fine powder (OX50 manufactured by Nippon Aerosil Co., Ltd.) was not used. . The evaluation results are shown in Table 1.

Comparative Example 2
It was carried out in the same manner as in Example 1 except that 1 part by weight of silica fine powder (OX50 manufactured by Nippon Aerosil Co., Ltd.) and no thermosetting resin fine powder (Epester S manufactured by Nippon Shokubai Co., Ltd.) were used. . The evaluation results are shown in Table 1.

Comparative Example 3
The same procedure as in Example 1 was performed except that thermosetting resin fine powder (Epester S, manufactured by Nippon Shokubai Co., Ltd.) and silica fine powder (OX50, manufactured by Nippon Aerosil Co., Ltd.) were not used. The evaluation results are shown in Table 1.

Claims (5)

Powder for powder molding consisting of 0.1 to 10 parts by weight of the following component (II) and 0.05 to 1 part by weight of the component (III) per 100 parts by weight of the following component (I).
Component (I): heat having an average particle size of 30 to 1000 μm and a melt flow rate measured at a load of 21.18 N and a temperature of 230 ° C. according to JIS K-7210 (1976) of 10 to 200 g / 10 minutes Plastic elastomer powder Component (II): Thermosetting resin fine powder having an average particle size of 0.005 to 10 μm Component (III): Inorganic fine powder having an average particle size of 0.005 to 0.8 μm The powder for powder molding according to claim 1, wherein the thermoplastic elastomer powder is a powder containing an olefin thermoplastic elastomer and a styrene thermoplastic elastomer. The powder for powder molding according to claim 1 or 2, wherein the thermosetting resin fine powder is a melamine resin powder. The powder for powder molding according to any one of claims 1 to 3, comprising 0.1 to 10 parts by weight of the following component (IV) per 100 parts by weight of the component (I).
Component (IV): inorganic fine powder having an average particle size of 1 to 10 μm A powder compact formed by powder molding the powder for powder molding according to any one of claims 1 to 4.