Two-color-molding resin composition and two-color- molded article

Description: TECHNICAL FIELD [Detailed description of the invention]

【0001】

[Technical field to which the invention belongs]

The present invention relates to a resin composition for two-color molding and a two-color molded product. More specifically, a resin composition for two-color molding (particularly a resin composition for a secondary material) which is excellent in moldability and can impart high adhesion to a primary material (primary molded product) and two-color molding using the same. Regarding goods.

【0002】

[Conventional technology]

Crystalline thermoplastic polyester resins, especially polybutylene terephthalate resins, are excellent in mechanical properties, electrical properties, and other physical and chemical properties, and have good workability. It is used in a wide range of applications such as electronic parts. The crystalline thermoplastic polyester resin is used alone for various molded products, but depending on the field of application, various reinforcing agents, additives, etc. may be added for the purpose of improving its properties, especially mechanical properties. Is being done. In fields where such high mechanical strength and rigidity are required, fibrous reinforcing agents such as glass fiber and carbon fiber are usually used.

【0003】

On the other hand, among the multicolor molding (or multiple molding) methods, in the two-color molding method, a specific resin (primary material) is molded to obtain a primary molding resin, and then another resin (secondary material) is added to this primary material. ) Is molded to obtain a molded product in which the two types of resins are in close contact with each other. In such a two-color molding method, for example, resins having different properties can be used as a primary material and a secondary material to obtain a composite molded product exhibiting the characteristics of each resin. In recent years, it has become possible to perform two-color molding while moving the mold by the DSI method (die slide molding method), the DRI method (die rotary molding method), etc., which enable simultaneous molding. However, in two-color molding, the adhesion between the primary material and the secondary material becomes a problem. If the adhesion is not sufficient, the two materials are easily peeled off from the adhesion surface, and it is difficult to impart sufficient functions to the molded product.

【0004】

In order to improve the adhesion, a method of raising the molding processing temperature of the secondary material higher than that of the primary material is often adopted, but it is applied because the molding processing temperature and thermal stability of the secondary material are restricted. In addition to the narrow range that can be deployed, sufficient adhesion cannot be obtained. In particular, when the primary material and the secondary material are different types of resins, it is difficult to obtain high adhesion strength by the above method.

【0005】

Japanese Unexamined Patent Publication No. 9-141686 discloses a composite molded product in which a primary molded product made of an amorphous thermoplastic polyester resin and a polyalkylene terephthalate resin are integrally molded and have excellent airtightness and adhesion. ing. However, in this document, the primary material is constrained to amorphous thermoplastic polyester resin.

【0006】

[Problems to be Solved by the Invention]

Therefore, an object of the present invention is to use a two-color molding resin composition capable of achieving stable moldability and high adhesion even if the primary side resin and the secondary side resin are different in two-color molding. The purpose is to provide two-color molded products. Another object of the present invention is to provide a resin composition for secondary molding capable of improving adhesion without raising the secondary molding temperature so much, and a two-color molded product using the same. Still another object of the present invention is to provide a two-color molded product and a resin composition for two-color molding having high mechanical strength. Another object of the present invention is to provide a two-color molded product having high gloss and good appearance.

【0007】

[Means for solving problems]

As a result of diligent studies to achieve the above object, the present inventors have used polyalkylene terephthalate and / or polyalkylene naphthalate in combination with a styrene resin and an inorganic filler in two-color molding. The present invention has been completed by finding that the adhesion and the two-color moldability can be improved even if the next molding temperature is low.

【0008】

That is, the resin composition for two-color molding of the present invention comprises 100 parts by weight of at least one polyester resin selected from (A) polyalkylene terephthalate resin and polyalkylene naphthalate resin, and (B) styrene resin 10. It is composed of about 100 parts by weight, (C) about 0 to 30 parts by weight of polycarbonate resin, and (D) about 10 to 150 parts by weight of inorganic filler. The polyester resin may contain about 5 to 40% by weight of comonomer units, and the styrene resin may be an acrylonitrile-styrene resin, a rubber-modified styrene resin, or the like. As the inorganic filler, a fibrous filler, a non-fibrous filler and the like can be used.

【0009】

Further, in the present invention, in the method for producing the resin composition for two-color molding, the resin composition in the two-color molded product composed of the primary material (primary side resin) and the secondary material (secondary side resin). Also included is a two-color molded product using the above as a secondary material, and a method for producing a two-color molded product in which the resin composition is injection-molded with respect to the primary material. In the present specification, the primary material and the primary molded product mean a molded product to be subjected to secondary molding, and are not limited to a single resin molded product, but a molding in which a plurality of resin molded products are compositely integrated. It may be a product.

【0010】

BEST MODE FOR CARRYING OUT THE INVENTION

The resin composition for two-color molding of the present invention comprises at least one polyester resin selected from (A) polyalkylene terephthalate resin and polyalkylene naphthalate resin, (B) styrene resin, and (D). It is composed of an inorganic filler. The resin composition may further contain (C) a polycarbonate-based resin.

[(A) Polyester-based resin] As the polyester-based resin (A), a polyalkylene terephthalate-based resin and a polyalkylene naphthalate-based resin can be used. The polyester resin (A) includes polyalkylene terephthalates such as polyethylene terephthalate and polybutylene terephthalate (particularly poly C)._2-4 Polyalkylene naphthalates (especially poly C) such as alkylene terephthalates, polyethylene naphthalates, polybutylene naphthalates)_2-4 (Alkylene naphthalate), alkylene terephthalate and / or alkylene naphthalate is the main unit, and at least one of the dicarboxylic acid component (terephthalic acid and / or naphthalenedicarboxylic acid) and alkylene glycol is another dicarboxylic acid (comonomer) or Copolyesters substituted with other diols (comonomer) and the like are included. These polyester resins can be used alone or in combination of two or more.

【0011】

Preferred polyester-based resins are polybutylene terephthalate-based resins and polybutylene naphthalate-based resins, particularly polybutylene terephthalate-based resins. These resins are obtained, for example, by polycondensing terephthalic acid, naphthalenedicarboxylic acid or an ester-forming derivative thereof with butanediol (particularly 1,4-butanediol) or an ester-forming derivative thereof. .. Preferred polyester-based resins include copolyesters. Copolyester usually has 1 to 40 mol%, preferably 5 to 40 mol%, particularly about 10 to 30 mol% of comonomer units.

【0012】

Examples of the dicarboxylic acid component (comonomer component) other than terephthalic acid and / or naphthalenedicarboxylic acid include aliphatic dicarboxylic acids (for example, succinic acid, adipic acid, pimeric acid, suberic acid, azelaic acid, sebacic acid, and dodecanedicarboxylic acid. , Hexadecanedicarboxylic acid, dimeric acid and other dicarboxylic acids having about 6 to 40 carbon atoms, preferably dicarboxylic acids having about 6 to 14 carbon atoms), alicyclic dicarboxylic acids (for example, 1,4-cyclohexanedicarboxylic acid, 1, 3-Cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid and other dicarboxylic acids with about 8 to 12 carbon atoms), aromatic dicarboxylic acids (for example, isophthalic acid, phthalic acid, diphenyldicarboxylic acid, diphenoxyetanedicarboxylic acid, diphenyl ether) Dicarboxylic acids (dicarboxylic acids having about 8 to 14 carbon atoms such as dicarboxylic acids and diphenylsulfone dicarboxylic acids), or ester-forming derivatives thereof can be mentioned. The dicarboxylic acid component includes alicyclic dicarboxylic acids such as tetrahydrophthalic acid, tetrahydroterephthalic acid, tetrahydroisophthalic acid, and hymic acid, and halogens such as tetrabromophthalic acid, tetrabromoterephthalic acid, tetrachlorophthalic acid, and het acid. The contained dicarboxylic acid can also be used, and as equivalent components, hydroxycarboxylic acids such as p-β-hydroxyethoxybenzoic acid, p-hydroxybenzoic acid, hydroxyphenylacetic acid, hydroxynaphthoic acid, glycolic acid, and hydroxycaproic acid, and propiolactone , Butyrolactone, caprolactone, lactone such as valerolactone and the like may be used. Dicarboxylic acid components other than terephthalic acid and / or naphthalene dicarboxylic acid may be used alone or in combination of two or more. Further, if necessary, a polyvalent carboxylic acid such as trimellitic acid, trimesic acid, or pyromellitic acid may be used in combination.

【0013】

Preferred dicarboxylic acid components other than terephthalic acid and / or naphthalenedicarboxylic acid include aliphatic dicarboxylic acids having 6 to 14 carbon atoms (preferably 6 to 12 carbon atoms) such as adipic acid and sebacic acid, isophthalic acid, and phthalic acid. It contains aromatic dicarboxylic acids having about 8 to 12 carbon atoms such as acids, or derivatives thereof (acid anhydrides, lower alkyl esters, etc.). Further preferable dicarboxylic acid components include adipic acid, isophthalic acid and the like.

【0014】

As the diol component (comonomer component), alkylene glycols having about 2 to 12 carbon atoms other than butanediol (for example, ethylene glycol, trimethylene glycol, propylene glycol, tetramethylene glycol, hexamethylene glycol, octanediol, decamethylene glycol, etc. Neopentyl glycol, aliphatic glycol having about 2 to 10 carbon atoms such as 1,3-octanediol), polyoxyalkylene glycol [Glyol having about 2 to 4 carbon atoms in an alkylene group and having a plurality of oxyalkylene units , For example, di (oxyethylene) glycol, di (oxypropylene) glycol, di (oxytetramethylene) glycol, tri (oxyethylene) glycol, tri (oxypropylene) glycol, tri (oxytetramethylene) glycol, etc.], both Diol composed of polyester oligomer having a hydroxyl group at the end, alicyclic diol (for example, cyclohexanediol, 1,1-cyclohexanedimethylol, 1,4-cyclohexanedimethylol, hydride bisphenol A, etc.), aromatic diol [For example, bisphenol A [2,2-bis (4-hydroxyphenyl) propane], diethoxybisphenol A, 4,4'-dihydroxybiphenyl, dihydroxyphenyl ether, 2,2-bis- (4-β-hydroxyethoxy) Phenyl) propane, 2,2-bis- (4-β-hydroxypropoxyphenyl) propane, 2,2-bis- (4-β-hydroxyethoxyphenyl) sulfone, xylene glycol, naphthalenediol, etc.], as well as hydroquinone And so on.

【0015】

Examples of the diol component include alkylene oxide adducts such as alkylene oxide adducts of bisphenol A (for example, ethylene oxide 2 mol adducts, propylene oxide 3 mol adducts, etc.), tetrabromobisphenol A, and tetrabromobisphenol A alkylenes. Halogenated diols such as adducts of oxides (such as ethylene oxide and propylene oxide) can also be used. Further, if necessary, a polyol such as glycerin, trimethylolpropane, trimethylolethane, or pentaerythritol or an ester-forming derivative thereof may be used in combination.

【0016】

These diol components may be used alone or in combination of two or more. Preferred diol components are linear alkylene glycol having about 2 to 6 carbon atoms (ethylene glycol, 1,4-butanediol, etc.), polyoxyalkylene glycol having an oxyalkylene unit having about 2 to 4 repetitions [diethylene glycol, etc.] Poly (oxy-linear C_2-4Glycols containing alkylene) units], 1,4-cyclohexanedimethylol, especially alkylene glycols are preferred.

【0017】

In the modified polyester resin, the modifying group (comonomer residue) to be introduced is preferably an isophthalic acid residue and / or an alkylene glycol residue. In particular, a modified polyester resin containing isophthalic acid and / or alkylene glycol as a comonomer, particularly a modified polybutylene terephthalate resin is preferable.

【0018】

The polyester resin may have a branched chain structure as well as a linear structure, or may be crosslinked, as long as the melt moldability is not impaired.

【0019】

The modified polyester resin may be used in combination with an unmodified polyester resin (particularly, polybutylene terephthalate homopolymer, polybutylene naphthalate homopolymer, etc.). If necessary, the polyester resin may be used in combination with a polyester elastomer, a liquid crystal polyester, or the like. The modified ester resin containing the comonomer unit as described above has a lower melt processing temperature than the unmodified polyester resin, and when used as the primary resin (primary material), the secondary resin (secondary material). Adhesion is improved due to the widening difference in melting temperature between the resin and the resin, and when used as a secondary resin (secondary material), the adhesion is improved and the thermal decomposition of the primary material is suppressed. The color molded product suppresses the formation of burrs, has a good appearance, and exhibits excellent moldability. In particular, when it is used as a resin for secondary molding, characteristics such as adhesion and moldability can be greatly improved even if the melting processing temperature of the primary material is low.

【0020】

The melting point of the modified polyester resin is adjusted depending on whether it is used as a primary material or a secondary material, and is, for example, about 150 to 230 ° C, preferably about 160 to 220 ° C. The heat of fusion of the modified polyester resin is, for example, about 10 to 45 J / g, preferably about 15 to 40 J / g. In two-color molding, the melting temperature of the secondary material is usually higher than the melting temperature of the primary material. The molecular weight of the polyester resin is not particularly limited, and can be selected from, for example, a weight average molecular weight of 10,000 to 500,000, preferably about 20,000 to 200,000.

【0021】

In the present invention, by adding (B) styrene resin to (A) polyester resin, the melting temperature of the secondary material is extremely high regardless of whether it is used as the primary material or the secondary material in two-color molding. Adhesion to the mating material can be improved without raising the temperature, and the mechanical strength of the molded product can be improved accordingly.

[(B) Styrene-based resin] The styrene-based resin can be composed of a single or copolymer of an aromatic vinyl compound, a copolymer of an aromatic vinyl compound and a copolymerizable vinyl monomer, and a rubber-modified styrene-based resin. .. Examples of the aromatic vinyl compound include styrene and alkyl styrene (for example, vinyl toluene such as o-, m- and p-methyl styrene, p-ethyl styrene, p-isopropyl styrene, butyl styrene, pt-butyl styrene and the like). , Α-alkylstyrene (eg, α-methylstyrene, etc.), halostyrene (eg, o-, m- and p-chlorostyrene, p-bromostyrene, etc.) and the like. These aromatic vinyl monomers can be used alone or in combination of two or more. Preferred styrene-based monomers include styrene, vinyltoluene, α-methylstyrene and the like, and styrene is particularly preferable.

【0022】

Examples of the copolymerizable vinyl monomer include (meth) acrylonitrile, (meth) acrylic acid alkyl ester, vinyl ester-based monomer (vinyl acetate, etc.), and hydroxyl group-containing monomer [hydroxyethyl (meth) acrylate. , Hydroxy C such as hydroxypropyl (meth) acrylate_1-4Alkyl (meth) acrylate, etc.], glycidyl group-containing monomer [glycidyl (meth) acrylate, etc.], carboxyl group-containing monomer [(meth) acrylic acid, maleic anhydride, fumaric acid, etc.], imide-based monomer (Maleimide, N-methylmaleimide, N-phenylmaleimide, etc.) and the like. (Meta) acrylic acid alkyl esters include methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, t-butyl (meth) acrylate, hexyl (meth) acrylate, (meth). C of (meth) acrylate such as octyl acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate_1-20Includes alkyl esters. These vinyl monomers can be used alone or in combination of two or more.

【0023】

Preferred styrene-based resins include acrylonitrile-styrene copolymer (AS resin), methyl methacrylate-styrene copolymer (MS resin), rubber-modified styrene-based resin (for example, rubbery polymer, aromatic vinyl compound, and acrylonitrile). Copolymer with a copolymerizable vinyl monomer). The rubber-modified styrene-based resin is composed of a copolymer of the styrene-based resin and a rubbery polymer, for example, a random copolymer, a graft copolymer, and a block copolymer. The microdomain structure of the rubber-modified styrene resin is not particularly limited.

【0024】

In the rubber-modified styrene resin, examples of the rubber polymer include butadiene rubber, styrene-butadiene rubber, isoprene rubber, ethylene-vinyl acetate copolymer, acrylic rubber, ethylene-propylene rubber (EPDM), and chlorinated polyethylene. Available. These rubber components can be used alone or in combination of two or more.

【0025】

Preferred rubber-modified styrene-based resins include styrene-butadiene-styrene (SBS resin), styrene-isoprene-styrene (SIS resin), acrylonitrile-butadiene-styrene copolymer (ABS resin), and acrylonitrile-acrylic rubber-styrene co-weight. Combined (AAS resin), acrylonitrile-chlorinated polyethylene-styrene copolymer (ACS resin), acrylonitrile-ethylene-propylene rubber-styrene copolymer, acrylonitrile-EPDM-styrene copolymer (AES resin), methyl methacrylate- Examples thereof include a butadiene-styrene copolymer (MBS resin). In particular, ABS resin, AAS resin, AES resin (particularly ABS resin) and the like are preferable. These resins can be used alone or in combination of two or more.

【0026】

In the resin composition for two-color molding of the present invention, the ratio of the styrene resin is 10 to 100 parts by weight (for example, 10 to 80 parts by weight), preferably 10 to 60 parts by weight, based on 100 parts by weight of the polyester resin. It is about a part by weight (for example, about 15 to 50 parts by weight), and usually about 20 to 50 parts by weight. If the amount of the styrene-based resin is less than 10 parts by weight, the solidification rate of the resin composition is high, and the degree of penetration of the styrene-based resin onto the surface of the resin composition is reduced. descend. On the other hand, if it exceeds 100 parts by weight, the molding cycle may increase, the thermal stability at the time of melting may decrease, or the releasability may decrease.

【0027】

If necessary, a (C) polycarbonate-based resin may be added to the resin composition for two-color molding of the present invention to improve the adhesion to the mating material. Since the polycarbonate resin is amorphous, it can be combined with a crystalline polyester resin such as a polybutylene terephthalate resin to reduce the crystallization rate and delay the solidification rate, and also with the polybutylene terephthalate resin. Effectively improves the interfacial adhesion with styrene resin.

【0028】

[(C) Polycarbonate-based resin] A polycarbonate-based resin (for example, polycarbonate) is obtained by reacting a divalent phenol with a carbonate precursor by a solution method or a melting method.

【0029】

Preferred divalent phenols include, for example, 2,2-bis (4-hydroxyphenyl) propane (also known as bisphenol A), bis (4-hydroxyphenyl) methane, 1,1-bis (4-hydroxyphenyl) ethane, 1 , 1-bis (4-hydroxyphenyl) butane, 2,2-bis (4-hydroxy-3,5-dimethylphenyl) propane, 2,2-bis (4-hydroxy-3.5-dibromophenyl) propane, 2, Bis (4-hydroxy-3-methylphenyl) propane, bis (3,5-dibromo-4-hydroxyphenyl) propane, bis (3,5-dichloro-4-hydroxyphenyl) propane, etc. Hydroxyphenyl) Alkanes; Bis (4-hydroxyphenyl) cycloalkanes such as 2,2-bis (4-hydroxyphenyl) cyclopentane; Bis (4-hydroxyphenyl) such as sulfide Hydroxyphenyl) sulfides; bis (4-hydroxyphenyl) sulfone; bis (4-hydroxyphenyl) sulfoxides; bis (4-hydroxyphenyl) ethers; hydroquinone; 4,4-dihydroxybiphenyl and the like. These divalent phenols can be used alone or in combination of two or more. Particularly preferred divalent phenols include bis (4-hydroxyphenyl) alkanes, especially bisphenol A. These divalent phenols may be homopolymers or copolymers of divalent phenols. It may also be a thermoplastic randomly branched polycarbonate obtained by reacting a polyfunctional aromatic with a divalent phenol and / or a carbonate precursor.

【0030】

Carbonyl precursors include carbonyl halides (typically phosgenes), carbonyl esters (typically diphenyl carbonates) or haloformates (typically dihaloformates of divalent phenols), which can be used as mixtures. .. The obtained polycarbonate resin may be used alone or in combination of two or more.

【0031】

As the polycarbonate resin, a polycarbonate resin having a bisphenol skeleton (particularly, a bisphenol A type polycarbonate resin) is often used. The polycarbonate-based resin used in the present invention is particularly preferably one having a high flow rate. The viscosity average molecular weight of the polycarbonate resin is, for example, 1 × 10.⁴~10×10⁴Degree.

【0032】

The ratio of (C) polycarbonate-based resin is about 0 to 30 parts by weight, preferably about 5 to 20 parts by weight, based on 100 parts by weight of polyester-based resin such as (A) polybutylene terephthalate-based resin. When the proportion of the polycarbonate-based resin exceeds 30 parts by weight, when the resin composition is used as a secondary material, the thermal stability of the polyester-based resin is lowered and it becomes necessary to raise the molding processing temperature. There is a risk that the molding cycle will be extended and the resin of the mating material will decompose.

[(D) Inorganic filler] (D) Inorganic filler imparts high mechanical strength, impact strength and heat resistance to the molded product. The inorganic filler may be either a fibrous filler or a non-fibrous filler, and may be used as a mixture of both. Fibrous fillers include glass fibers, asbestos fibers, carbon fibers, ceramic fibers (silica fibers, silica / alumina fibers, zirconia fibers, boron nitride fibers, silicon nitride fibers, boron fibers, potassium titanate, etc.), whiskers, etc. Examples thereof include inorganic fibrous substances such as metal fibers (stainless steel, aluminum, titanium, copper, brass, etc.). In particular, glass fiber, carbon fiber and the like are preferable. The inorganic filler of the present invention also includes a high melting point organic fibrous substance (for example, polyamide resin (aromatic polyamide or the like), fluororesin, acrylic resin or the like).

【0033】

Non-fibrous fillers include carbon black, silica, quartz powder, glass beads, glass powder, milled fiber, silicates (calcium silicate, kaolin, talc, clay, caustic soil, wolastonite, etc.), metal oxidation. Materials (iron oxide, titanium oxide, zinc oxide, alumina, etc.), metal carbonates (calcium carbonate, magnesium carbonate, etc.), sulfates (calcium sulfate, barium sulfate, etc.), ceramics (silicon carbide, boron nitride, boron nitride, etc.) And various metal powders and the like. Among the non-fibrous fillers, examples of the plate-shaped filler include mica, glass flakes, and various metal foils.

【0034】

The non-fibrous filler is a granular or plate-like filler having an average primary particle size of 20 μm or less (for example, about 0.5 to 20 μm), preferably 0.5 to 15 μm (for example, 1.0 to 10 μm) (for example, glass beads). , Milled fiber, talc, kaolin, mica, etc.) are preferred.

【0035】

These fillers can be used alone or in combination of two or more, and the fibrous filler (particularly glass fiber or carbon fiber) and the non-fibrous filler (particularly powder granules or plates having an average primary particle diameter of 20 μm or less) can be used. The combination with the state filler) is particularly preferable for obtaining a two-color molded product having high mechanical strength, dimensional stability accuracy, and good appearance characteristics.

【0036】

When using these fillers, a converging agent or a surface treatment agent (functional surface treatment agent) may be used if necessary. Examples of the convergent or surface treatment agent include functional compounds such as epoxy compounds, isocyanate compounds, silane compounds, and titanate compounds. The filler may be surface-treated or converged in advance, and the convergent or surface-treating agent may be added together with the filler at the time of material preparation.

【0037】

The amount of the inorganic filler (D) used can be selected within a range that does not impair the mechanical strength and adhesion of the molded product, and (A) 10 to 150 parts by weight per 100 parts by weight of the polybutylene terephthalate resin (for example, 20 to 20 to). 130 parts by weight), preferably about 40 to 120 parts by weight. If the amount of the inorganic filler used is too large, the filler may be exposed on the surface of the molded product and the adhesion may be lowered, and if it is too small, it becomes difficult to obtain practically sufficient mechanical strength.

【0038】

The amount of the converging agent and the surface treatment agent used is 10% by weight (for example, 0.01 to 10% by weight) or less, preferably 0.05 to 5% by weight, based on the filler.

【0039】

Combining the components (A) and (B) with the component (C) and the inorganic filler (D), if necessary, not only provides high mechanical strength, but also has good appearance characteristics without the filler being raised. A two-color molded product having a high degree of adhesion between the primary side resin and the secondary side resin can be obtained.

【0040】

[Other Additives] To the resin composition of the present invention, general additives added to thermoplastic resins and the like may be further added. Additives include, for example, stabilizers (antioxidants, UV absorbers, light stabilizers, heat stabilizers, etc.), antistatic agents, flame retardants, lubricants, mold release agents, colorants such as dyes and pigments, and plasticizers. Examples include agents. In particular, the addition of phosphorus-based compounds improves the heat retention stability during molding, and when a polycarbonate resin is used in combination, the resin deteriorates due to the ester exchange reaction between (A) polyester-based resin and (C) polycarbonate resin. It is effective because it has a high effect of suppressing the above, maintains high thermal stability, and suppresses decomposition of the molten resin during molding.

【0041】

As the phosphorus-based compound, organic phosphite and a metal phosphate are mainly suitable. Examples of the compound having a spiro ring among organic phosphite include the following compounds. Dialkyl Pentaerist Reel Diphos Fight [For example, Di-C such as Distearyl Penta Erist Reel Diphos Fight_2-18Alkyl pentaerist reel diphosphite, etc.], Diphenyl pentaerist reel diphosphite, bis (alkyl-substituted phenyl) pentaerist reel diphosfite [eg, bis (2,4-di-t-butylphenyl) penta Eristoryl Diphos Fight, Bis (2,6-di-t-Butylphenyl) Penta Eristo Reel Difos Fight and other bis (Di C)_1-6Alkylphenyl) pentaeristril diphosphite; bis (2,6-di-t-butyl-4-methylphenyl) pentaeristril diphosphofite, bis (2,6-di-t-butyl-4-methylphenyl) Ethylphenyl) Pentaerist reel Diphosphite and other bis (2,6-di C)_1-6Alkyl-4-C_1-4Alkylphenyl) pentaeristril diphosphite, etc.], Tetrakis (phenyl) -4,4'-biphenylene phosphite, tetrakis (alkyl-substituted phenyl) -4,4'-biphenylene phosphite [for example, tetrakis (2,4' -Di-t-butylphenyl) -4,4'-biphenylene phosphite, tetrakis (2,6-di-t-butylphenyl) -4,4'-biphenylene phosphite and other tetrakis (di-C)_1-6Alkylphenyl) -4,4'-biphenylene phosphite; tetrakis (2,6-di-t-butyl-4-methylphenyl) -4,4'-biphenylene phosphite and other tetrakis (2,6-diC)_1-6Alkyl-4-C_1-4Alkylphenyl) -4,4'-biphenylene phosphite] and the like can be exemplified.

【0042】

Examples of the metal phosphate salt include alkaline earth metal phosphates such as calcium primary phosphate and magnesium primary phosphate, alkali metal phosphates such as sodium primary phosphate and potassium primary phosphate, or theirs. Examples include hydrates (monohydrate, etc.). These phosphorus compounds can be used alone or in combination of two or more. The amount of the phosphorus compound added is, for example, 0.001 to 2.0 parts by weight, preferably 0.01 to 0.8 parts by weight, based on 100 parts by weight of the polyester resin (A). When the phosphorus compound is not added or the amount added is small, the thermal stability decreases due to the transesterification reaction as described above, and when the amount added exceeds 2.0 parts by weight, the influence of coloring and the gas derived from the additive is large. This leads to a decrease in adhesion, which is not preferable.

【0043】

It is effective to use the phosphorus compound in combination with an antioxidant typified by hindered phenols in order to further enhance the thermal stability. The antioxidant is not limited to hindered phenols, and may be a phosphorus-based, amine-based, sulfur-based, hydroquinone-based, or quinoline-based antioxidant. As the antioxidant, hindered phenols and phosphorus-based antioxidants are usually used.

【0044】

Hindered phenols include, for example, 2,6-di-t-butyl-p-cresol; 1,3,5-trimethyl-2,4,6-tris (3,5-di-t-butyl-4). -Hydroxybenzyl) benzene; 2,2'-methylenebis (4-methyl-6-t-butylphenol, 4,4'-methylenebis (2,6-di-t-butylphenol), 4,4'-butylidenebis (3-hydroxybenzyl) benzene; Alkylene bis (t-butylphenol) such as methyl-6-t-butylphenol); 1,6-hexanediol-bis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] etc. C_2-10Alkylenediol-bis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], glycerintris [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], etc. C_3-8Alkylenetriol-bis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate]; pentaerythritol tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] Such as C_4-8Alkylene tetraol-bis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate]; triethylene glycol-bis [3- (3-t-butyl-5-methyl-4-hydroxyphenyl) propionate] ) Propionate] etc. di or trioxy C_2-4Alkylenediol-bis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate]; n-octadecyl-3- (4', 5'-di-t-butylphenol) propionate, n-octadecyl Long-chain alkyl groups such as -3- (4'-hydroxy-3', 5'-di-t-butylphenol) propionate, stearyl-2- (3,5-di-t-butyl-4-hydroxyphenol) propionate Propionates having (t-butylphenol); include phosphate esters such as distearyl-3,5-di-t-butyl-4-hydroxybenzylphosphonate.

【0045】

Phenyl antioxidants include, for example, triphenylphosphite, trisnonylphenylphosphite, 2,2-methylenebis (4,6-di-t-butylphenyl) octylphosphite, 4,4'-butylidenebis (3). Includes -methyl-6-t-butylphenyl) ditridecylphosphite, tris (2,4-di-t-butylphenyl) phosphite, tris (2-t-butyl-4-methylphenyl) phosphite, etc. .. These antioxidants can be used alone or in combination of two or more.

【0046】

The content of the antioxidant can be selected from, for example, 0.01 to 1 part by weight, preferably 0.05 to 0.7 parts by weight (particularly 0.05 to 0.5 parts by weight) with respect to 100 parts by weight of the polyester resin.

【0047】

The resin composition for two-color molding of the present invention is prepared by mixing the polyester resin (A), the styrene resin (B), the inorganic filler (D), and if necessary, the polycarbonate (C). Can be manufactured.

【0048】

The preparation can be easily carried out by the equipment and method generally used as a conventional resin composition preparation method. For example, (1) a method of collectively mixing a predetermined amount of the components constituting the composition of the present invention and melt-kneading them with a uniaxial or biaxial extruder to obtain pellets, and (2) having two or more raw material inlets. With a uniaxial or biaxial extruder, resin, stabilizers, pigment components, etc. are charged from the first inlet and melt-kneaded, then the inorganic filler is charged from the second raw material inlet and melt-kneaded. It can be prepared by a method of obtaining pellets or the like.

【0049】

The resin composition for two-color molding of the present invention is composed of the polyester resin (A), the styrene resin (B), the inorganic filler (D), and if necessary, the polycarbonate (C). In color molding, high adhesion can be exhibited regardless of whether it is used as a primary side resin (primary material) or a secondary side resin (secondary material). It is particularly preferable to use it as a secondary material.

【0050】

In this case, the primary material may be composed of a polyester resin, but if at least the above-mentioned styrene resin, particularly a rubber-modified styrene resin or the like is used as the primary material, the present invention may be used even if the secondary molding temperature is low. The adhesion between the resin composition and the resin composition can be maintained high. The rubber-modified styrene resin constituting the primary material (resin composition for primary molding) includes, for example, ABS resin, AAS resin, ACS resin, acrylonitrile-EPDM-styrene copolymer and the like. The primary material may be composed of a polymer blend or a polymer alloy composed of a combination of the rubber-modified styrene resin and the polycarbonate resin. In particular, ABS resin, AAS resin, or a polymer blend of these resins and a polycarbonate resin is preferable.

【0051】

Further, the two-color molded product using the resin composition can be manufactured by a conventional two-color molding method, for example, a core rotation type, a core back type, a core slide type, or the like, and the mold is slid or rotated. The same can be done by DSI (die slide molding method) or DRI (die rotary molding method).

【0052】

Since the two-color molded product of the present invention has high mechanical strength and is excellent in heat resistance, weather resistance and appearance characteristics (high glossiness, etc.), external mechanical parts such as automobile interior / exterior parts, OA equipment and home appliances, and external parts. Suitable for fields such as covers.

【0053】

[Effect of the invention]

Since the resin composition for two-color molding of the present invention is composed of a polyester-based resin (A), a styrene-based resin (B), an inorganic filler (D), and, if necessary, a polycarbonate-based resin (C). Even if the two-color molding is performed with different resins, stable moldability and high adhesion can be achieved, and a two-color molded product having high mechanical strength can be obtained.

【0054】

[Example]

Hereinafter, the present invention will be described in detail based on Examples, but the present invention is not limited to these Examples.

【0055】

The polyester-based resin (A), styrene-based resin (B), polycarbonate-based resin (C), inorganic filler (D), and primary material used in Examples and Comparative Examples are as follows. 1. (A) Polyester resin (A-1): Polybutylene terephthalate (melting point 225 ° C) (A-2): Modified polybutylene terephthalate (melting point 205 ° C) (12 mol% isophthalic acid-modified polybutylene terephthalate copolymer) 2. (B) Styrene resin (B-1): Acrylonitrile-butadiene-styrene copolymer (ABS resin, Sevian V660SF manufactured by Daicel Chemical Industries, Ltd.) (B-2): Acrylonitrile-acrylic rubber-styrene copolymer (AAS resin, Vitax V6700 manufactured by Hitachi Kasei Co., Ltd.) 3. (C) Polycarbonate resin (C-1): Polycarbonate 4. (D) Inorganic filler (D-1): Glass fiber (D-2): Mica 5. Primary material : (B-2) AAS resin : Polycarbonate / ABS polymer blend (PC / ABS resin, Novalon S1100 manufactured by Daicel Chemical Industries, Ltd.) : Same material as secondary material In addition, the physical characteristics of the molded product were evaluated as follows. (Tensile strength) ASTM Measured according to D-638. (Adhesion evaluation) (1) Tensile shear strength The ASTM No. 1 dumbbell piece was molded and bisected, and the half piece was placed in the mold again. Next, the other half of the resin was ejected into the mold cavity to obtain a two-color molded piece in which the two types of resin were in close contact with each other. The tensile shear strength of the obtained two-color molded piece was measured in accordance with ASTMd-638 and used as an index for adhesion evaluation. (2) Close contact A flat plate (length 80 mm x width 80 mm x thickness 1 mmt) was molded from resin, and this flat plate was placed in a mold (length 80 mm x width 80 mm x thickness 3 mmt). Next, the resin was ejected into the mold cavity to obtain a two-color molded piece in which the two types of resin were in close contact with each other, and a blade was inserted into one end of the interface of the obtained molded piece and torn. The fracture form was evaluated according to the following criteria. The two types of resin are not peeled off at the interface and are destroyed at places other than the interface (base metal destruction). The two types of resin are not peeled off at the interface, and one resin is partially scooped out (partially destroyed base material). The two types of resin peel off at the interface, but one resin partially adheres to the other (partially cohesive failure). × Two types of resin peel off at the interface (interface peeling) The resin injection molding used in Examples and Comparative Examples was performed under the following conditions of an injection molding machine (manufactured by Toshiba Corporation, 80t). Molding condition Cylinder temperature (° C) Nozzle: 260 C1: 250 C2: 240 C3: 220 Injection speed 2.0 m / min Holding pressure 600 kg / cm² Mold temperature 90 ° C Molding machine: Toshiba 80t Molding condition Cylinder temperature (° C) Nozzle: 280 C1: 270 C2: 260 C3: 260 Injection speed 2.0 m / min Holding pressure 600 kg / cm² Mold temperature 90 ° C Examples 1 to 12 and Comparative Examples 1 to 8 A resin composition is extruded by a twin-screw extruder using a polyester resin (A), a styrene resin (B), a polycarbonate resin (C) and an inorganic filler (D) at the ratios shown in Tables 1 and 2. Was prepared. The resin composition was melt-kneaded in a cylinder and injected as a secondary material into a mold cavity in which a part of a test piece of the primary material was arranged to obtain a molded product (test piece). The above evaluation was performed using this molded product. The results are shown in Tables 1 and 2 together with the combination of primary and secondary materials and molding conditions. For comparison, an example in which the styrene resin was not used and an example in which the styrene resin was used in an excessive amount were evaluated in the same manner as in the examples. The results are shown in Table 2.

【0056】

[table 1]

<img file="JP2000007902A_D0001.tif" />【0057】

[Table 2]

<img file="JP2000007902A_D0002.tif" />As is clear from the table, as compared with the comparative example in which the styrene resin (B) was not used, the examples showed high tensile shear strength and a good adhesion state, and were excellent in adhesion.