JP2006281575A - Plated resin composition and plating coating body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a plating coating body which can be improved in rigidity (impact strength etc.) and toughness (flexural elasticity etc.) even if it is a thin-walled plated body. <P>SOLUTION: A plating coat is formed on the surface of at least one part of the plated body formed from a thermoplastic resin composition to form the plating coating body. The thermoplastic resin composition is composed of a polycarbonate resin (A), a styrene resin (B) containing at least a rubber-containing styrene resin, an inorganic filler (C) at least one part of which can be eluted by an acid, a flame retarder (D), and as required an acid or epoxy-modified olefinic compound (E). The ratio (by weight) of the polycarbonate resin (A) to the styrene resin (B) is 67/33-95/5. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a plated coating body which is improved in rigidity (impact strength and the like) and toughness (bending elasticity and the like) by plating even when molded into a thin molded article and is excellent in electromagnetic shielding properties.

  Resin molded products are used in the case of portable electronic devices (for example, notebook computers, electronic notebooks, mobile phones, video cameras, etc.) from the viewpoints of thinning, weight reduction, design freedom, etc. The level of electromagnetic shielding and thinning is increasing.

  In these applications, a composition obtained by adding a non-halogen flame retardant (such as a phosphate ester flame retardant) to a blend of polycarbonate resin / acrylonitrile-styrene resin (ABS, AS, etc.) is mainly used. Yes. In applications where electromagnetic shielding and thinning are required at a higher level, polycarbonate resin / ABS or ASA (acrylonitrile-styrene-acrylic rubber copolymer), non-halogen flame retardant, and resin containing carbon fiber Compositions have also been used. In addition, in case applications, a molded product formed of the composition as described above may be plated to give various functions (for example, electromagnetic shielding properties, decorative properties, etc.) to the case.

  For example, JP 2000-190328 A (Patent Document 1) discloses a diene monomer and at least one monomer selected from an aromatic vinyl compound, a vinyl cyanide compound, and a (meth) acrylic ester compound. The inorganic filler (C) is added to 100 parts by weight of a resin composition comprising 15 to 70% by weight of a copolymer (A) with a body and an amorphous thermoplastic resin (B) other than the copolymer (A). In the molding process of the reinforced thermoplastic resin composition containing 1 to 150 parts by weight (glass fiber, carbon fiber, heat-resistant organic fiber, etc.), the glass transition temperatures of component (A) and component (B) are Ta and Tb ( When Ta <Tb), the main mold temperature is less than Ta ° C., and the maximum temperature of the cavity surface when the resin composition is in contact with the mold cavity surface is [Ta + 1] to [Tb + 50] ° C. It has been described. And in patent document 1, the deformation | transformation of the polymer component of the diene monomer by the shearing force accompanying shaping | molding is prevented, and the anchor effect with a plating film is improved by etching at a plating process. However, when carbon fiber is used, although toughness can be improved to some extent even with a thin wall, it is economically disadvantageous because carbon fiber is expensive.

  Japanese Patent Application Laid-Open No. 2004-2897 (Patent Document 2) describes thermoplastic resin (A) (ABS resin, etc.) 1 to 97% by weight, polycarbonate (B) 1 to 97% by weight, flame retardant (C) (organic phosphorus Thermoplastic resin composition for trays containing 1 to 30% by weight of an organic compound and the like and 1 to 30% by weight of an inorganic filler (D) (such as talc) and having excellent flame retardancy, rigidity, plating adhesion, etc. (However, (A) + (B) + (C) + (D) = 100 wt%) is disclosed. However, in Patent Document 2, the plating adhesion cannot be sufficiently improved, and the flame-retardant property is insufficient for a thin molded product.

In JP-A-11-170434 (Patent Document 3), (A) 10 to 65% by weight of a polycarbonate resin and (B) a thermoplastic graft copolymer obtained by grafting a vinyl cyanide compound and an aromatic vinyl compound to a diene rubber component. (C) 1-50 parts by weight of a fibrous inorganic filler (wollastonite) mainly composed of calcium silicate and (D) a carboxyl group in 100 parts by weight of a resin composition substantially comprising 90-35% by weight of a polymer And / or a plated product plated on a molded product formed from a polycarbonate resin composition containing 0.02 to 5 parts by weight of an olefin wax containing a carboxylic anhydride group.
JP 2000-190328 A (Claim 1, paragraph numbers [0035] and [0043]) JP 2004-2897 A (Claims 1, 3 and 5, paragraph numbers [0001] and [0034]) JP-A-11-170434 (Claim 1)

  Accordingly, an object of the present invention is to provide a plated coating body in which the adhesion between the plating film and the object to be plated is improved, and the flame resistance, rigidity and toughness are excellent even if the object to be plated is thin. .

  Another object of the present invention is to provide a plated covering that is prevented from floating of the filler, is excellent in appearance characteristics, and is excellent in electromagnetic shielding properties.

  As a result of diligent studies to achieve the above-mentioned problems, the present inventors have made a combination of a polycarbonate resin, a rubber-containing styrene resin, an inorganic filler that can be at least partially eluted by an acid, and a flame retardant. When the body is formed, the adhesion to the plating film is high, and even if it is made thin, flame retardancy can be improved, and rigidity (bending elastic modulus etc.) and toughness (impact resistance etc.) increase with plating. The present invention has been completed by finding that it can be improved.

  That is, the plating covering of the present invention is a plating covering in which a plating film is formed on at least a part of the surface of the object to be plated formed of the thermoplastic resin composition, and the thermoplastic resin composition Is a polycarbonate resin (A), a styrene resin (B) containing at least a rubber-containing styrene resin, an inorganic filler (C) that can be at least partially eluted by a mineral acid, and a flame retardant (D). The carbon fiber content is 5% by weight or less. The ratio (weight ratio) between the polycarbonate resin (A) and the styrene resin (B) is about polycarbonate resin (A) / styrene resin (B) = 67/33 to 95/5. In such a plated covering, even if the average thickness of the object to be plated is 1.2 mm (preferably 1.0 mm, especially 0.8 mm), the flame retardancy of the object to be plated is greatly improved. The flame retardancy of the object to be plated according to -94 is V-1 or V-0.

  When a bending elastic modulus is measured in accordance with ISO178 for a plated covering using a flat plate-like object having a thickness of 1 mm, the bending elastic modulus may be about 5,000 to 50,000 MPa. In the plated cover, the thickness of the plated film may be about 10 to 100 μm.

  The plated coating body has high adhesion between the plated film and the object to be plated. For example, in a cross-cut tape peeling test, 100 grid-like grids are formed at intervals of 1 mm, and an adhesive tape is formed on the grid-like grids. When the film is peeled after being adhered, 95 or more of the 100 grids remain.

The viscosity-average molecular weight of the polycarbonate resin (A) may be about 1.5 × 10 ^{4 to} 3 × 10 ⁴ . The styrenic resin (B) includes acrylonitrile-butadiene rubber-styrene resin, acrylonitrile-acrylic rubber-styrene resin, acrylonitrile-ethylenepropylene rubber-styrene resin, methyl methacrylate-butadiene rubber-styrene resin, butadiene rubber-styrene. You may comprise at least 1 type selected from resin and these hydrogenated substances. The inorganic filler (C) is composed of at least one selected from particulate silicate (such as talc and mica), fibrous silicate (such as wollastonite) and whisker-like carbonate (such as calcium carbonate whisker). it can. The inorganic filler (C) may be composed of particulate or fibrous silicate having a silicon dioxide content of about 35 to 55% by weight, and the proportion of the inorganic filler (C) is polycarbonate. About 5-50 weight part may be sufficient with respect to 100 weight part of total amounts of resin (A) and styrene-type resin (B). The inorganic filler (C) may be wollastonite having a number average fiber length of 1 to 30 μm, a number average fiber diameter of 0.1 to 10 μm, and an aspect ratio of 1.5 to 5.

Even if the ratio of the said flame retardant (phosphorus flame retardant etc.) (D) is about 1-50 weight part with respect to 100 weight part of total amounts of polycarbonate-type resin (A) and styrene-type resin (B). Good. The thermoplastic resin composition may further contain an acid-modified or epoxy-modified olefin compound (E) (such as an acid-modified or epoxy-modified olefin resin). About 100-170 degreeC may be sufficient as melting | fusing point of the said acid-modified or epoxy-modified olefin resin. Further, the weight average molecular weight of the modified olefin resin may be about 1.5 × 10 ⁴ to 30 × 10 ⁴ . The ratio of the acid-modified or epoxy-modified olefin compound (E) may be about 0.1 to 10 parts by weight with respect to 100 parts by weight of the total amount of the polycarbonate resin (A) and the styrene resin (B). .

  In the plated covering of the present invention, the object to be plated is formed by combining a polycarbonate-based resin, a styrene-based resin containing at least a rubber-containing styrene-based resin, a specific inorganic filler, and a phosphorus-based flame retardant. Inorganic fillers are eluted by etching treatment associated with the plating process, and the anchor effect can improve the adhesion between the plating film and the object to be plated, and because the plating adhesion is high, the object to be plated is thin. However, rigidity and toughness can be improved, and flame retardancy can also be improved. Further, it is possible to improve the appearance characteristics by preventing the filler from being lifted, and to obtain a plated covering having excellent electromagnetic shielding properties. Furthermore, when the object to be plated is formed of a thermoplastic resin containing an acid-modified or epoxy-modified olefin compound, the strength (weld strength, etc.) of the object to be plated and the plated covering can be further improved. When an inorganic filler such as wollastonite or mica is used, warpage can be reduced and weld strength can be improved.

[Plating coating]
The plated covering is composed of a body to be plated formed of a thermoplastic resin composition and a plating film formed on at least a part of the surface of the body to be plated.

(Thermoplastic resin composition (plated resin composition))
The thermoplastic resin composition constituting the object to be plated includes a polycarbonate resin (A), a styrene resin (B) containing at least a rubber-containing styrene resin, and an inorganic filler that can be at least partially eluted by an acid. (C) and a flame retardant (D). The thermoplastic resin composition may further contain an acid-modified or epoxy-modified olefin compound (E) as necessary.

(A) Polycarbonate resin Polycarbonate resins include aromatic polycarbonate resins such as dihydric phenols and carbonate precursors [for example, carbonyl halides (phosgene etc.), carbonyl esters (diphenyl carbonate etc.) or haloformates (divalent). And the like can be obtained by reacting with a conventional method (interfacial polycondensation method, transesterification method, etc.).

Bivalent phenols include bisphenols such as 4,4′-dihydroxydiphenyl; bis (hydroxyphenyl) alkanes such as bis (4-hydroxyphenyl) methane, 1,1-bis (4-hydroxyphenyl) Ethane, 2,2-bis (4-hydroxyphenyl) propane (bisphenol A), 2,2-bis (4-hydroxy-3-methylphenyl) propane, 2,2-bis (4-hydroxy-3,5- Bis (4-hydroxyphenyl) C _1-6 alkane such as dimethylphenyl) propane, 2,2-bis (4-hydroxyphenyl) butane, 2,2-bis (4-hydroxyphenyl) -3,3-dimethylbutane Bis (hydroxyphenyl) cycloalkanes such as 1,1-bis (4-hydroxyphenyl) cyclo Hexane, 1,1-bis (4-hydroxyphenyl) -3,3,5-bis such trimethylcyclohexane (4-hydroxyphenyl) C _5-8 cycloalkanes; 9,9-bis (hydroxyphenyl) fluorenes Bis (hydroxyphenyl) alkylbenzenes, for example, bis {1,3-bis {2- (4-hydroxyphenyl) propyl} benzene, 1,4-bis {2- (4-hydroxyphenyl) propyl} benzene, etc. (4-hydroxyphenyl) alkyl} benzenes; 4,4′-dihydroxydiphenyl ketone, 4,4′-dihydroxydiphenyl ether, 4,4′-dihydroxydiphenyl sulfone, 4,4′-dihydroxydiphenyl sulfoxide, 4,4 ′ -A dihydroxy diphenyl ester etc. can be illustrated. These dihydric phenols can be used alone or in combination of two or more.

As dihydric phenols, bis (4-hydroxyphenyl) alkanes (bisphenol A), bis (4-hydroxyphenyl) C _5-8 cycloalkanes and the like are usually used in many cases.

The polycarbonate resin may have a linear structure or a branched structure. In addition, the branched structure may be a small amount of trifunctional or higher polyphenols such as tris (hydroxyphenyl) alkanes [1,1,1-tris (4-hydroxyphenyl) ethane, 1,1,1-tris if necessary. (3,5-dimethyl-4-hydroxyphenyl) ethane etc.] can be used. Further, the polycarbonate resin may have a hydroxyl group at the terminal, and the terminal may be blocked. End capping can be performed with monofunctional phenols (phenol, C _1-20 alkylphenol, etc.). Polycarbonate resins can be used alone or in combination of two or more.

The molecular weight of the polycarbonate resin is usually a viscosity average molecular weight of 1 × 10 ⁴ to 10 × 10 ⁴ , preferably 1 × 10 ^{4 to} 5 × 10 ⁴ (for example, 1.5 × 10 ^{4 to} 3 × 10 ⁴ ). More preferably, it may be about 1.5 × 10 ^{4 to} 2.7 × 10 ⁴ . The viscosity average molecular weight can be measured using methylene chloride.

(B) Styrenic resin The styrene resin is not particularly limited as long as it contains at least a rubber-containing styrene resin. For example, a rubber-containing styrene resin [for example, a rubber-reinforced styrene resin (at least a styrene monomer is grafted to a rubber component) Polymerized styrene-based graft resin or rubber-grafted styrene-based resin)] alone may be used, or the rubber-containing styrene-based resin and the non-rubber-reinforced styrene-based resin may be used in combination.

  Styrene monomers (aromatic vinyl monomers) of styrene resins include styrene, α-methylstyrene, vinyltoluene (o-, m- or p-methylstyrene), vinylxylene, ethylstyrene, p -T-butylstyrene, vinylnaphthalene, halostyrene (monobromostyrene, dibromostyrene, etc.), etc. are mentioned. These styrenic monomers can be used alone or in combination of two or more. Of these styrenic monomers, styrene, α-methylstyrene and vinyltoluene are usually used, and at least styrene is often used.

Styrene monomers may be used in combination with copolymerizable monomers. Examples of the copolymerizable monomer include vinyl cyanides (such as (meth) acrylonitrile), (meth) acrylic monomers [(meth) acrylic acid C _1- such as methyl methacrylate, ethyl acrylate, ethyl methacrylate, etc. ₁₈ alkyl esters; hydroxyalkyl (meth) acrylates such as hydroxyethyl (meth) acrylate; glycidyl (meth) acrylate; aryl (meth) acrylates such as phenyl acrylate; cycloalkyl (meth) acrylates such as cyclohexyl acrylate; Aralkyl (meth) acrylates such as benzyl methacrylate], maleimide monomers [maleimide, N-methylmaleimide, N-phenylmaleimide, etc.], α, β-unsaturated carboxylic acids [(meth) acrylic acid, maleic acid , Anhydrous male , Phthalic acid, and itaconic acid], and others. These copolymerizable monomers can also be used alone or in combination of two or more. The ratio of the copolymerizable monomer is, for example, 0 to 100 parts by weight, preferably 5 to 80 parts by weight, and more preferably about 10 to 60 parts by weight with respect to 100 parts by weight of the styrene monomer. There may be. As the styrene resin, a copolymer using vinyl cyanide is also preferable. In such a styrene resin, the proportion of vinyl cyanide is, for example, 5 parts by weight with respect to 100 parts by weight of the styrene monomer. ˜100 parts by weight, preferably 10 to 95 parts by weight, more preferably about 20 to 90 parts by weight.

  As the rubber-containing styrenic resin, a conventional method, for example, at least a styrenic monomer (and the copolymerizable monomer if necessary) in the presence of a rubber component, a conventional method (bulk polymerization, suspension polymerization). Rubber-reinforced styrene resin obtained by graft polymerization by solution polymerization, emulsion polymerization, etc.) can be used. In the rubber-containing styrene resin, the rubber component includes various rubbers such as diene rubber (polybutadiene, polyisoprene, butadiene-isoprene copolymer, random or block styrene-butadiene copolymer, etc.), ethylene-α- Olefin copolymer rubber (ethylene-propylene rubber, ethylene-butene rubber, etc.), ethylene-propylene-diene rubber, ethylene-acrylate copolymer rubber (ethylene-ethyl acrylate rubber, ethylene-butyl acrylate rubber, etc.), ethylene-vinyl acetate Examples include polymers, acrylic rubbers (such as polybutyl acrylate), silicone rubbers, and composite rubbers. In the rubber-containing styrenic resin, as the copolymerizable monomer, usually, at least one selected from vinyl cyanides and methyl methacrylate is often used.

  Examples of rubber-containing styrene-based resins include impact-resistant polystyrene (HIPS resin) in which a styrene monomer is graft-polymerized on a rubber component, and acrylonitrile (A) and / or methyl methacrylate (M) and a styrene-based rubber component. Polymer grafted with monomer (S) [ABS resin whose rubber component is butadiene rubber, MBS resin, MABS resin, ASA resin whose rubber component is acrylic rubber, and AES resin whose rubber component is ethylene propylene rubber Etc.], or these hydrogenated products. These rubber-containing styrenic resins can be used alone or in combination of two or more.

  In the rubber-containing styrenic resin, the content of the rubber component is, for example, 40% by weight or less (for example, 2 to 30% by weight), preferably about 5 to 25% by weight, particularly about 5 to 20% by weight.

  The rubber-containing styrenic resin is usually composed of a styrenic resin matrix and a rubber component dispersed in the form of particles in the matrix. The form of the rubber component dispersed in the matrix is not particularly limited, and may include a core / shell structure, an onion structure, a salami structure, and the like.

  The particle diameter of the rubber component constituting the dispersed phase can be selected according to the use of the resin composition. For example, the volume average particle diameter is about 0.1 to 10 μm, preferably about 0.2 to 7 μm, particularly 0.5 to It can be selected from a range of about 5 μm. Furthermore, the particle size distribution of the rubber component may show a single peak or a plurality of peaks.

  Among rubber-containing styrene resins, acrylonitrile-butadiene rubber-styrene (ABS) resin, acrylonitrile-acrylic rubber-styrene (AAS) resin, acrylonitrile-ethylenepropylene rubber-styrene (AES) resin, methyl methacrylate-butadiene rubber-styrene (MBS) resin, butadiene rubber-styrene resin (HIPS), and at least one selected from these hydrogenated products are preferable.

  Non-rubber reinforced styrene resins used in combination with the rubber-containing styrene resin include polystyrene, acrylonitrile-styrene copolymer (AS resin), styrene- (meth) acrylic acid monomer copolymer (styrene- (Meth) acrylic acid copolymer, styrene-methyl methacrylate copolymer (MS resin), methyl methacrylate-acrylonitrile-styrene copolymer (MAS resin), etc.), styrene-maleic anhydride copolymer (SMA resin) Etc. can be exemplified. Of these non-rubber reinforced styrene resins, polystyrene (PS resin), AS resin, and the like are often used.

The molecular weight (gel permeation chromatography, in terms of polystyrene) of the matrix of the styrene resin or rubber-containing styrene resin is, for example, a weight average molecular weight of 1 × 10 ^{4 to} 100 × 10 ⁴ , preferably 5 × 10 ⁴ to 50 × 10. ⁴ , especially about 10 × 10 ⁴ to 50 × 10 ⁴ .

  The ratio (weight ratio) between the polycarbonate resin (A) and the styrene resin (B) is, for example, the former / the latter = 67/33 to 95/5, preferably 68/32 to 95/5 (for example, 70 / 30 to 95/5), more preferably 75/25 to 93/17 (for example, 75/25 to 90/10), particularly about 75/25 to 85/15.

  In addition, the composition containing the polycarbonate resin (A) and the styrene resin (B) may form a polymer blend or a polymer alloy. If necessary, a compatibilizer such as an oxazoline compound, an epoxidized styrene-butadiene block copolymer or a hydrogenated product thereof may be added to such a system.

(C) Inorganic filler The inorganic filler (C) is not particularly limited as long as at least a part thereof can be eluted with a mineral acid. Usually, silicate (silicate mineral etc.), carbonate (carbonic acid) Metal carbonates such as calcium whiskers) can be used. These inorganic fillers can be used alone or in combination of two or more.

  Examples of the silicate include kaolin, talc, clay, pyrophyllite, mica, montmorillonite, bentonite, wollastonite, sepiolite, zonolite, natural silica, synthetic silica, zeolite, diatomaceous earth, halosite, attapulgite, and the like. It is done. Of these silicates, talc, mica and wollastonite (especially mica and wollastonite) are preferred.

The content of silicon dioxide SiO ₂ in the silicate is preferably smaller from the viewpoint of elution by acid, but is usually 35% by weight or more in many cases. The content of silicon dioxide in the silicate is, for example, about 35 to 70% by weight, preferably 40 to 65% by weight, more preferably about 40 to 55% by weight (for example, 40 to 50% by weight). Also good.

  The shape of the inorganic filler (C) may be any of granular, plate-like, and fibrous, but is preferably granular or fibrous. Among inorganic fillers (C), in particular, at least one selected from particulate silicate (talc, mica, etc.), fibrous silicate (wollastonite, etc.) and whisker-like carbonate (calcium carbonate whisker) Is preferred.

  The average particle diameter of the granular inorganic filler can be selected from a range of, for example, about 0.1 to 100 μm, preferably 0.5 to 80 μm, and more preferably about 1 to 50 μm. For example, the average particle diameter of mica may be about 1 to 80 μm, preferably about 1.5 to 60 μm, and more preferably about 2 to 50 μm. The average particle diameter of talc may be about 0.5 to 50 μm, preferably about 0.5 to 20 μm (for example, 0.5 to 10 μm).

  Wollastonite is a silicate mineral containing calcium, and is in a fibrous form even when finely pulverized due to its crystal structure. The production area of wollastonite is not particularly limited, and may be North America, Latin America, East Asia including China, and the like.

  The number average fiber length of wollastonite is, for example, 50 μm or less, preferably 30 μm or less (for example, 1 to 30 μm, particularly about 1 to 25 μm), more preferably 20 μm or less (for example, about 1 to 20 μm). 3 to 15 μm (for example, about 5 to 10 μm). The number average fiber diameter may be, for example, 0.1 to 10 μm (for example, 0.1 to 7 μm, preferably 0.5 to 7 μm, more preferably about 1 to 5 μm).

  The number ratio of the fiber length of 5 to 25 μm with respect to the entire wollastonite is not particularly limited, and may be, for example, about 20 to 75% (preferably 20 to 70%, more preferably 25 to 65%). In the present invention, even if the number ratio is 50% or less (for example, 25 to 45%), preferably about 30 to 45% (for example, 35 to 45%), the surface characteristics of the molded product are improved. High reinforcement can be imparted.

  Furthermore, the aspect ratio (average fiber length / average fiber diameter) of the wollastonite fiber is 1.5 to 50 (for example, 1.5 to 30, preferably 1.5 to 20, and more preferably 1.5 to 10). In particular, it is about 1.5 to 5). In the present invention, even if the aspect ratio is small, high reinforcement can be imparted, and the aspect ratio may be about 1.5 to 5, preferably about 1.5 to 4, and more preferably about 1.5 to 3.

  The whiteness of wollastonite may be, for example, 85 or more, preferably 89 to 96, and more preferably about 90 to 96. The oil absorption of wollastonite (linseed oil ml / 100 g) may be about 25 to 78 (for example, 30 to 80, preferably 40 to 80, more preferably 50 to 75).

  Further, the pH of the wollastonite is usually about 9.5 to 10.6 (for example, 9.7 to 10.6), and the ignition loss is 0.7 to 3% by weight (for example, 0.8. 7 to 2.5% by weight, preferably 0.7 to 2% by weight, more preferably 0.7 to 1.8% by weight), and 1.5% by weight or less, particularly 1.2% by weight or less. There may be. The loss on ignition is measured by heating a sample from which moisture has been removed by heating at a rate of 10 ° C./min using a thermogravimetric analysis TGA (Thermogravimetric Analysis) and calculating a weight loss value at 1300 ° C. it can.

  The fiber length and fiber diameter can be measured as follows.

  Fiber length: Observed with an optical microscope (magnification of objective lens 20 times), and measured the length of each wollastonite fiber. From the measured values, the number average fiber length and the ratio of the number of fiber lengths of 5 to 25 μm were determined. calculate. Observation with an optical microscope may be performed by putting the sample into a mixed solution of purified water and a dispersant and dispersing the sample so that the wollastonite fibers do not overlap each other.

  The observation image is captured as image data in a CCD camera having about 290,000 pixels, and the obtained image data is 5000 using a program for calculating the absolute maximum length of the image data using an image analyzer. The fiber length is calculated for the above fibers.

  Fiber diameter: A wollastonite fiber is observed with a scanning electron microscope, each fiber diameter is measured, and a number average fiber diameter is calculated from the measured value. The sample is completely dried, subjected to a Pt sputtering treatment, a scanning electron micrograph is taken at a magnification of 1000 times, and the fiber diameter is measured for 1000 fibers using the scale as an index.

  Wollastonite may be pulverized and classified by a pulverizer (jet mill or the like). In addition, the wollastonite fiber may be subjected to purification treatment (for example, removal treatment of impurities, iron oxide, calcium oxide, aluminum oxide, etc.) as necessary.

  Wollastonite is a surface treatment agent such as a silane coupling agent (such as glycidyl alkoxysilanes, alkylalkoxysilanes, alkoxysilanes such as aminoalkylalkoxysilanes), titanate coupling agents, etc. You may surface-treat with a ring agent etc.

  The proportion of the inorganic filler (C) is, for example, 5 to 50 parts by weight, preferably 7 to 45 parts by weight with respect to 100 parts by weight of the total amount of the polycarbonate resin (A) and the styrene resin (B). Preferably it may be about 10 to 40 parts by weight (for example, 10 to 35 parts by weight).

  Such an inorganic filler (C) can be at least partially eluted with a mineral acid (for example, hydrochloric acid, sulfuric acid, phosphoric acid, chromic acid (such as chromic anhydride, dichromic acid, etc.)). That is, when the object to be plated formed of the thermoplastic resin composition is etched in the pre-plating process, at least a part of the inorganic filler is eluted by an etching solution containing a mineral acid such as chromic acid or sulfuric acid. Although the base is a polycarbonate resin, holes are formed by elution of the inorganic filler, and the surface of the molded body can be roughened. When the molded body subjected to such an etching process is plated, the adhesion between the plating film and the object to be plated can be greatly improved by the anchor effect.

  In the present invention, by using such an inorganic filler, even if the object to be plated is thin, the strength of the plated coating can be improved by plating, so that the toughness and strength can be improved without using carbon fiber or the like. It can be improved sufficiently. In the plated coating of the present invention, the carbon fiber content in the thermoplastic resin composition constituting the object to be plated is, for example, 5% by weight or less (for example, about 0 to 5% by weight), preferably 3% by weight. Hereinafter, it may be 2% by weight or less.

(D) Flame retardant As the flame retardant, a halogen-based flame retardant may be used. Usually, a non-halogen-based flame retardant, for example, an organic acid metal salt-based flame retardant (perfluoroalkanesulfonic acid metal salt, trihalobenzene) Organic carboxylic acids such as sulfonic acid metal salts, diphenyl sulfone-disulfonic acid metal salts, diphenyl sulfone sulfonic acid metal salts, alkali metal (Na, K) salts, alkaline earth metal salts, etc. of organic sulfonic acids), phosphorus flame retardants , Silicone-based flame retardants, phosphazene-based flame retardants, metal oxides (such as antimony oxide), and the like]. These flame retardants can be used alone or in combination of two or more. Of these flame retardants, phosphorus-based flame retardants are preferred. The phosphorus-based flame retardant may be used in combination with other flame retardants.

  Phosphorus flame retardants include aromatic phosphate ester flame retardants, red phosphorus flame retardants (red phosphorus, stabilized red phosphorus whose surface is coated with a thermosetting resin and / or an inorganic compound, etc.), etc. .

  Of these phosphorus flame retardants, aromatic phosphate ester flame retardants are preferred. Aromatic phosphate ester flame retardants include triphenyl phosphate, cresyl diphenyl phosphate, tris (tolyl) phosphate, tris (xylenyl) phosphate, resorcinol bis (diphenyl phosphate), hydroquinone bis (diphenyl phosphate), resorcinol bis (dioxy). Silenyl phosphate), hydroquinone bis (dixylenyl phosphate), 4,4′-biphenol bis (diphenyl phosphate), 4,4′-biphenol bis (dixylenyl phosphate), bisphenols (such as bisphenol A) Examples thereof include diphenyl phosphate), bisphenols (such as bisphenol A), and bis (dixylenyl phosphate). The aromatic phosphate ester flame retardant also includes a halogenated aromatic phosphate ester flame retardant. Examples of the halogenated aromatic phosphate ester flame retardant include halides of the aromatic phosphate ester flame retardant, such as tris (4-bromophenyl) phosphate, tris (2,4-dibromophenyl) phosphate, tris ( 2,4,6-tribromophenyl) phosphate), 2,2-bis (p-hydroxyphenyl) propane-trichlorophosphine oxide polycondensate (polymerization 1 to 3) phenol condensate (Asahi Denka Kogyo Co., Ltd.) "ADK STAB FP-700", "ADK STAB FP-750") and the like can be exemplified. Phosphorus flame retardants can be used alone or in combination of two or more.

  The flame retardant may be used in combination with a flame retardant aid. The flame retardant aid can be composed of, for example, an anti-drip agent or a fluorine resin. The flame retardant aid can usually be used in powder form. Examples of the fluororesin include polytetrafluoroethylene, polychlorotrifluoroethylene, polyvinylidene fluoride, and tetrafluoroethylene-hexafluoropropylene copolymer. Of these, polytetrafluoroethylene, particularly polytetrafluoroethylene having a fibril-forming ability is preferred.

  The amount of the flame retardant used is, for example, 1 to 50 parts by weight, preferably 5 to 40 parts by weight, more preferably 10 to 100 parts by weight of the total amount of the polycarbonate resin (A) and the styrene resin (B). About 35 parts by weight (for example, 15 to 35 parts by weight).

  The amount of the flame retardant aid used is, for example, 0.1 to 5 parts by weight, preferably 0.3 to 3 parts by weight, based on 100 parts by weight of the total amount of the polycarbonate resin (A) and the styrene resin (B). Part (for example, 0.5 to 3 parts by weight), more preferably about 0.5 to 2 parts by weight.

(E) Acid-modified or epoxy-modified olefin compound Acid-modified or epoxy-modified olefin compound includes acid-modified or epoxy-modified olefin wax [for example, polyolefin wax such as polyethylene, polypropylene wax, unsaturated polycarboxylic acid or acid thereof. Modified olefin wax treated with glycidyl group such as anhydride (maleic acid, maleic anhydride, etc.), glycidyl (meth) acrylate, etc .; and constituent monomer of the polyolefin wax (α-olefin such as ethylene, propylene, etc.) Other than the unsaturated carboxylic acid or acid anhydride ((meth) acrylic acid, maleic acid, maleic anhydride, etc.) as a polymerization component, modified olefin wax formed by copolymerization with glycidyl (meth) acrylate, etc.], Acid change Or an epoxy-modified olefin resin. These modified olefin compounds can be used alone or in combination of two or more. The modified olefin wax and the modified olefin resin may be used in combination. Among these modified olefin compounds, the thermoplastic resin composition can be efficiently modified, and high surface properties (surface smoothness) and heat resistance can be imparted to the molded product, and strength (impact resistance, weld strength, etc.) can be imparted. In view of improvement, it is preferable to use at least an acid-modified or epoxy-modified olefin resin.

  As the olefin resin constituting the acid-modified or epoxy-modified olefin resin, an α-olefin such as ethylene, propylene, butene, methylpentene-1, or a copolymer thereof can be used. Examples of such olefin resins include ethylene resins (polyethylene, ethylene-propylene copolymer, ethylene-butene copolymer, etc.), propylene resins (polypropylene, propylene-ethylene random copolymer, propylene-ethylene). Examples thereof include block copolymers and propylene-butene copolymers. The olefin resin is preferably a propylene resin containing at least propylene.

  The modified olefin resin can be obtained by copolymerization of the α-olefin and a modifier, grafting of the modifier to the olefin resin, or the like. As the modifier, a monomer having a carboxyl group or an acid anhydride group [for example, (meth) acrylic acid, crotonic acid, maleic acid, maleic anhydride, fumaric acid, etc.], a monomer having a glycidyl group or an epoxy group Examples thereof include glycidyl (meth) acrylate and the like. These monomers can also be used alone or in combination of two or more. As the modifier, (meth) acrylic acid or maleic anhydride is often used.

The weight average molecular weight (gel permeation chromatography, in terms of polystyrene) of the modified olefin resin is, for example, 1.5 × 10 ⁴ to 30 × 10 ⁴ (for example, 2 × 10 ^{4 to} 25 × 10 ⁴ ), preferably 2 5 × 10 ⁴ to 23 × 10 ⁴ (for example, 2.5 × 10 ^{4 to} 20 × 10 ⁴ ), more preferably 2.7 × 10 ^{4 to} 20 × 10 ⁴ (for example, 5 × 10 ^{4 to} 17 ×). About 10 ⁴ ), and usually about 3 × 10 ^{4 to} 16 × 10 ⁴ . The number average molecular weight is, for example, 0.5 × 10 ⁴ to 10 × 10 ⁴ (for example, 0.75 × 10 ⁴ to 10 × 10 ⁴ ), preferably 0.8 × 10 ^{4 to} 7.5 × 10. ^It may be about ⁴ (for example, 0.8 × 10 ^{4 to} 5 × 10 ⁴ ). The number average molecular weight is usually 1 × 10 ⁴ or more, for example, 1 × 10 ^{4 to} 7 × 10 ⁴ (for example, 1 × 10 ^{4 to} 6 × 10 ⁴ ), preferably 1.5 × 10 ^{4 to} 7 × 10. ⁴ (for example, 1.5 × 10 ⁴ to 4 × 10 ⁴ ), more preferably about 1.7 × 10 ^{4 to} 5 × 10 ⁴ (for example, 2 × 10 ^{4 to} 5 × 10 ⁴ ).

  The melting point of the modified olefin resin is high, and can be selected, for example, from a range of about 100 to 170 ° C., and is usually 120 to 170 ° C. (eg, 125 to 165 ° C.), preferably 130 to 165 ° C. (eg, 135 to 165 ° C. About 140 to 165 ° C.

  In the modified olefin compound, the introduction amount (modification amount) of the acidic group or epoxy group is, for example, 0.1 to 10% by weight (0.5 to 10% by weight), preferably 1 to 10% by weight, and more preferably 1 It may be about ˜5% by weight. Furthermore, the saponification value (KOHmg / g) of the modified olefin resin is, for example, about 10 to 80, preferably about 10 to 70 (for example, 20 to 70), and more preferably about 10 to 60 (for example, 20 to 60). It is.

  The proportion of the modified olefin compound (such as a modified olefin resin) (E) is, for example, about 0.1 to 10 parts by weight with respect to 100 parts by weight of the total amount of the polycarbonate resin (A) and the styrene resin (B). For example, 0.1 to 5 parts by weight (for example, 0.1 to 3 parts by weight), preferably 0.2 to 2.5 parts by weight, and more preferably about 0.2 to 2 parts by weight. It may be.

  The ratio (weight ratio) between the inorganic filler (C) and the modified olefin compound (modified olefin resin, etc.) is, for example, the former / the latter = 99.5 / 0.5 to 50/50, preferably 99 / It may be about 1-60 / 40, more preferably 95 / 5-75 / 25 (for example, 93 / 7-85 / 15).

  The thermoplastic resin composition forming the object to be plated includes other resin components such as olefin resins (polyethylene resins, polypropylene resins, ionomers, methylpentene resins, etc.), vinyl alcohol resins (polyvinyl alcohol, Polyvinyl acetal), acrylic resins (polymethyl methacrylate, methyl methacrylate-styrene copolymer (MS resin), methyl methacrylate-acrylic ester copolymer, etc.), halogen-containing resins (polyvinyl chloride resin, chloride) Vinyl-vinyl acetate copolymers, fluororesins, etc.), polyester resins (aromatic polyester resins), polyamide resins, polyacetal resins, polyphenylene ether resins, polyphenylene sulfide resins, polysulfone resins, polyether sulfones. Resins, polyether imide resins, polyether ether ketone resins, thermoplastic elastomers (styrene type, olefin, polyester, and polyamide-based elastomer), may contain a rubber-like polymer.

  The thermoplastic resin composition further contains various additives such as fillers, stabilizers [thermal stabilizers (phosphorous acid, phosphoric acid, phosphonous acid, phosphonic acid, esters thereof, etc.), antioxidants (hinders). Dophenols, hindered amines, phosphorus antioxidants, etc.), UV absorbers (benzophenone UV absorbers, benzotriazole UV absorbers, triazine UV absorbers, etc.)], mold release agents [waxes (polyethylene Wax, higher fatty acid esters, fatty acid amides, etc.), silicone oils, etc.], antistatic agents, colorants and the like. As the filler, other inorganic fillers different from the component (C) [fibrous filler (glass fiber, carbon fiber, metal fiber, whiskers (potassium titanate, aluminum borate, etc.), etc.), plate-like filler Agents (glass flakes, etc.), granular fillers (glass beads, silica, alumina, titania, calcium carbonate, titanium oxide, etc.), organic fillers (fibrous fillers (aramid fibers, etc.), granular fillers ( Phenol resin particles, crosslinked styrene resin particles, crosslinked acrylic resin particles, etc.)].

  The thermoplastic resin composition is preliminarily mixed with conventional components such as (i) a mixer (tumbler, V-type blender, Henschel mixer, Nauta mixer, ribbon mixer, mechanochemical device, extrusion mixer, etc.). Melt kneading with a melt kneader (single screw or vent type twin screw extruder, etc.) and pelletizing with a pelletizing means (pelletizer, etc.), (ii) preparing a master batch of the desired component, (Iii) a method of supplying each component to a melt-kneader and melt-kneading to pelletize, (iv) a predetermined component (for example, the above-mentioned Modified olefin resin etc.) can be prepared by adding and kneading in the middle of the melt kneader.

  In the present invention, the object to be plated (base material) of the plating covering is formed of the resin composition containing the specific three components, so that it is thin [for example, an average thickness of 1.2 mm or less (for example, 0.4 to 1). .2 mm), preferably 1.0 mm or less (for example, about 0.5 to 1.0 mm), more preferably 0.8 mm or less (for example, about 0.6 to 0.8 mm)]. A practically sufficient flame retardancy can be imparted to the plated body. When the flame retardance is evaluated in accordance with UL-94 for a plate-like object to be plated, when the average thickness of the plate-like object to be plated is 0.8 to 1.2 mm, the UL-94 flame resistance standard is V. -1 or V-0 (preferably V-0).

  In the present invention, despite the formation of the object to be plated using a specific inorganic filler such as wollastonite, the plating process enables high rigidity and toughness (elastic modulus) comparable to those using carbon fiber. Etc.) is obtained. In the present invention, by using wollastonite or the like without using expensive carbon fibers, the rigidity and toughness (particularly toughness) can be controlled and improved by the degree of plating (such as the thickness of the plating film). It is also advantageous. That is, even if the resin composition to be plated is molded into a thin wall (thickness of 1 mm or less (for example, about 0.5 to 1 mm)), the thin molded product itself is not so high in rigidity and / or toughness. High rigidity and toughness can be imparted to the molded article.

  That is, when the bending elastic modulus is measured in accordance with ISO 178 for a plate-like object to be plated, when the thickness of the plate-like object to be plated is 1 mm, the bending elastic modulus is 2,500 to 15,000 MPa, preferably 3, 000 to 12,000 MPa, more preferably about 3,500 to 10,000 MPa. On the other hand, when the bending elastic modulus of a plated coating body in which a plating film is formed on the surface of a flat plate-shaped body having a thickness of 1 mm is measured according to ISO178, the bending elastic modulus of the plated coating body is, for example, 5 It is about 7,000 to 50,000 MPa, preferably about 6,000 to 45,000 MPa, and more preferably about 7,000 to 40,000 MPa. The bending elastic modulus is, for example, about 3,000 to 50,000 MPa (for example, 5,000 to 50,000 MPa), preferably about 5,000 to 40,000 MPa, and more preferably about 5,000 to 35,000 MPa. May be.

  Thus, in the present invention, the object to be plated is thin, for example, the thickness of the thinnest part is 0.5 to 1.5 mm, preferably 0.5 to 1.2 mm (for example, 0.5 to 1 mm), More preferably, even if the thickness is about 0.8 to 1 mm, practically sufficient rigidity and toughness can be imparted by plating treatment (for example, comparable to the case of using carbon fiber).

  A to-be-plated body is obtained by shape | molding the said thermoplastic resin composition by a conventional method, for example, injection molding, extrusion molding, blow molding, press molding, vacuum forming etc. As the body to be plated, for example, a case of various electric and / or electronic products (particularly, portable electronic devices) is often formed.

(Plating coating)
The plated coating is at least a metal or alloy, for example, a metal such as copper, nickel, zinc, chromium, or an alloy of these metals (nickel-zinc alloy, nickel-tin alloy, nickel-phosphorus alloy, nickel-cobalt-phosphorus alloy). A nickel base alloy such as a copper-nickel alloy or a copper-cobalt alloy; a zinc-base alloy such as an iron-zinc alloy or a zinc-cobalt alloy). The plating film should just be formed in at least one part of the surface of a to-be-plated body.

  The plating film may contain conventional plating additives (such as brighteners and colorants). In copper plating, brighteners such as sodium thiosulfate, potassium thiocyanate, and selenite, and colorants (dyes, pigments, etc.) may be used. In nickel plating, for example, brighteners [primary brighteners (saccharin, sodium naphthalene disulfonate, sodium naphthalene trisulfonate, paratoluenesulfonamide, etc.), secondary brighteners (coumarin, propargyl alcohol, quinoline, pyridine, allyl, etc. Sodium sulfonate, etc.)], and the above colorants may be used.

  The thickness of the plating film formed on the surface of the object to be plated may be, for example, 1 to 100 μm, preferably 5 to 100 μm (for example, 10 to 100 μm), and more preferably about 10 to 70 μm. In addition, when forming a plating film by chemical plating (electroless plating) and electroplating, the thickness of the chemical plating film is 0.1 to 3 μm, preferably 0.2 to 2 μm (for example, 0.2 to 1). About 5 μm).

  In the plated covering of the present invention, the object to be plated is formed with specific three components, so that the adhesion strength between the object to be plated and the plating film can be greatly improved. In the cross-cut tape peeling test, the adhesion strength between the object to be plated and the plating film was determined by forming notches reaching the base material (object to be plated) in the vertical and horizontal directions at intervals of 1 mm to form 100 grid-like grids. When the adhesive tape is adhered to the grid grid and then peeled off, it can be evaluated by the remaining number of grids, and 95 or more (for example, about 95 to 100) of the 100 grids. , Preferably 96-100 pieces, More preferably, about 97-100 pieces may remain.

  The plated covering is obtained by subjecting the object to be plated to chemical etching and electroplating by a conventional method. Usually, the object to be plated is degreased, chemically etched, chemically plated (electroless plating), and then electroplated in many cases. If necessary, solvent treatment, catalyzing treatment, etc. may be combined.

  The degreasing treatment (cleaning treatment) can be performed, for example, by immersing in a surfactant, an organic solvent (alcohol, acetone, etc.), or a mixture of these solvents. The degreasing temperature may be, for example, 10 to 70 ° C., preferably 20 to 60 ° C., more preferably about 30 to 60 ° C., depending on the type of the degreasing solvent. The degreasing time is not particularly limited, and may be about 1 to 15 minutes.

  Degreasing treatment followed by solvent treatment (pre-etching), for example, hydrocarbons such as xylene and toluene, ethers such as dioxane and tetrahydrofuran, amides such as dimethylformamide, sulfoxides such as dimethyl sulfoxide, organic solvents such as tetralin You may perform the process by.

In the chemical etching treatment, the object to be plated that has been degreased and pre-etched as necessary is treated with a mineral acid [sulfuric acid, hydrochloric acid, phosphoric acid, chromic acid (chromic anhydride, dichromic acid, dichromate (K ₂ Cr ₂ O ₇ etc. ) Etc.) soak in a strong inorganic acid etc.]. The mineral acids may be used alone or in combination of two or more. For example, chromic acid and other mineral acids (such as sulfuric acid and / or hydrochloric acid) may be combined, or a mixed solution of both may be used for etching treatment, and either one of chromic acid and other mineral acids. Etching may be performed by dipping in the other and then dipping in the other. Etching is usually often performed using a chromic acid-sulfuric acid mixed solution, a chromic acid-sulfuric acid-phosphoric acid mixed solution, or the like.

  In the case of a polycarbonate-based resin-based object to be plated, it is usually difficult to roughen the surface of the polycarbonate-based resin by an etching process, but in the present invention, such an etching process is included in the object to be plated. At least a part of the inorganic filler (C) elutes, holes are formed on the surface of the object to be plated, the surface becomes rough, and the adhesion with the plating film can be improved. In particular, rubber-containing styrene resins such as ABS resins are combined with polycarbonate resins, so that the rubber component is oxidized and eluted with mineral acid (chromic acid, etc.) and roughened, and mineral acid (sulfuric acid, hydrochloric acid, etc.). As a result, the inorganic filler (C) is eluted and the roughening is further promoted, and the plating property can be greatly improved.

  The temperature of the etching process may be, for example, about 40 to 80 ° C., preferably about 50 to 70 ° C. The etching processing time is not particularly limited, and may be, for example, about several tens of seconds to 20 minutes.

After the chemical etching treatment, a neutralization treatment, a catalyzing treatment and / or an accelerator treatment can be performed as necessary. The neutralization treatment can be performed using, for example, a strong inorganic acid such as hydrochloric acid, sulfuric acid, a mixture of hydrochloric acid and sulfuric acid. The catalytic treatment can be performed by precipitating Pd, Au, Ag, Pt or the like on the surface of the object to be plated. For example, the object to be plated that has been etched is immersed in a tin chloride solution, and Sn ^{2 Alternatively} , ⁺ may be adsorbed and immersed in a palladium chloride solution to precipitate Pd.

  The electroless plating can be performed by a conventional electroless plating method, for example, a dipping method or a spray method using a metal salt, a complexing agent and a reducing agent, and, if necessary, an additive or a stabilizer. Examples of metals used for electroless plating include copper, nickel, cobalt, gold, silver, palladium, iron, tin, indium, and alloys of these metals (these metals and phosphorus, boron, and / or tungsten, etc.) Alloys such as Co—P, Ni—Co—P, Ni—Co—B, Ni—Fe—P, Ni—WP, and the like. Of these metals, copper is preferred.

  As the electroless plating bath, an acid bath, a neutral bath, an alkali hydroxide bath, an ammonia alkali bath, or the like can be appropriately selected according to the type of the plating metal. Specific examples of the electroless plating bath include, for example, a copper plating bath (room temperature electroless copper plating bath, high-temperature high-speed electroless copper plating bath, etc.), nickel plating bath (acidic or neutral electroless nickel plating bath, basic non-electrolytic plating bath). Electrolytic nickel plating bath, nickel alloy plating bath such as electroless cobalt-phosphorous plating bath), electroless gold plating bath, electroless silver plating bath and the like.

  After the electroless plating, an activation treatment may be performed as necessary. The activation treatment can be performed using an inorganic strong acid such as sulfuric acid and / or hydrochloric acid.

  Electroplating (electroplating) is a conventional plating method, for example, using a substrate to be plated as a cathode in a plating bath containing a metal salt, a conductivity imparting agent, a hydrogen ion concentration adjusting agent, an additive, etc. This can be done by depositing metal on the surface of the object to be plated at a density. Examples of the plating metal include copper, nickel, chromium, zinc, cadmium, tin, gold, silver, palladium, rhodium, lead, iron, and alloys of these metals (for example, Cu-Ni-Cr, Ni-Cr, etc.) ) And the like.

  As an electrolytic plating bath, for example, an acidic bath such as a copper sulfate bath or a copper borofluoride bath, or an alkaline bath such as a copper cyanide bath or a copper pyrophosphate bath can be used. Matte nickel plating methods (Watt bath, nickel sulfamate bath, chloride bath, etc.), bright nickel plating methods (organic bright nickel plating, etc.) can be used. In chromium plating, a Sargent bath, a low-concentration chromium plating bath, a fluoride addition bath (for example, a chromic acid-sodium silicofluoride-sulfuric acid bath), an SRHS bath, a tetrachromate bath, a microcrack chromium plating bath, and the like can be used. In zinc plating, for example, a zincate bath, an amine bath, a pyrophosphoric acid bath, a sulfuric acid bath, a borofluoride bath, a chloride bath, and the like can be used.

  The electrolytic plating process may be performed once or a plurality of times. When performing the electrolytic plating process a plurality of times, the same plating process may be performed a plurality of times, or different plating processes may be performed a plurality of times. For example, after performing base plating or the like by electroless plating, nickel or the like may be plated. After performing base plating, intermediate plating such as nickel is performed, and final plating (decoration of chromium, cobalt alloy, gold, etc.) Plating, functional plating, etc.) may be performed.

  In addition, for the plating film, conventional plating additives such as brighteners [primary brighteners (sodium 1,5-naphthalenedisulfonate, sodium 1,3,6-naphthalenetrisulfonate, saccharin, etc.), secondary Brighteners (coumarin, 2-butene-1,4-diol, ethylene cyanohydrin, propargyl alcohol, formaldehyde, thiourea, quinoline, pyridine, sodium allyl sulfonate, etc.), coloring agents for coloring the plating film ( Pigments, dyes, and the like).

  In the plated covering according to the present invention, it is preferable that after the object to be plated is copper plated by electroless plating, nickel or a nickel alloy is plated by electrolytic plating. Specific examples of nickel plating include satellite nickel plating, bright nickel plating, semi-bright nickel plating, no leveling nickel plating, and velor nickel plating. If necessary, after electroless copper plating, electrolytic copper plating (bright copper plating, no leveling copper plating, etc.) may be performed, and further electrolytic nickel plating may be performed.

  If necessary, the surface of the plated covering may be further subjected to surface treatment such as chromate treatment or painting (spray clear coating, electrodeposition clear coating, electrodeposition coating, etc.) after electrolytic plating.

  The plated coating of the present invention can be used in various applications, for example, interior or exterior parts for vehicles, housing parts (cases, etc.) for precision equipment (digital cameras, portable information terminals, etc.), office automation OA equipment (personal computers, It can be applied to housing parts (cases, etc.) of printers, copiers, facsimiles, etc.

  Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited to these examples. In Examples and Comparative Examples, “parts” means “parts by weight” unless otherwise specified.

  In the examples and comparative examples, the characteristics of the molded products were evaluated as follows.

  Toughness (bending strength (MPa) and flexural modulus (MPa)): ISO 178 using a plated object having a thickness of 1 mm and a plated film having a plated film having a thickness of 15 μm or 50 μm formed on the surface of the object to be plated. Was subjected to a bending test, and the bending strength and flexural modulus (FM) were measured.

  Flame retardancy: In accordance with UL standard 94V, a vertical combustion test was performed on test pieces (without plating) having a thickness of 0.8 mm and 1.2 mm, and the rank of flammability was evaluated.

  Warpage: When a flat plate molded product with a length of 120 mm × width 120 mm × thickness 1 mm is placed on a flat plate and one corner of this molded product is pressed, the height from the flat plate is the highest among the other corners. For the high corner, the height from the flat plate was compared before and after plating, and the maximum deformation (maximum warpage) was evaluated. The case where the maximum deformation amount was 0 mm was evaluated as “no warp”, the case where it exceeded 0 mm and 1 mm or less was evaluated as “warp”, and the case where it exceeded 1 mm was evaluated as “warp”.

  Adhesiveness of plating film: A tape peeling test was carried out with an adhesive tape using a plating coated body in which a plating film having a thickness of 15 μm was formed on the surface of a body to be plated (thickness 1 mm), and the residual rate was evaluated. That is, in the above-mentioned plated coating body, cuts reaching the body to be plated are made in the vertical and horizontal directions at intervals of 1 mm on the plated coating to form 100 grid-like grids, and cellophane tape is applied to the grid-like grids for momentum. The tape peeling residual rate of the coating was evaluated by counting the number of the grids that peeled well and remained on the surface of the plating coating.

Examples 1-9 and Comparative Examples 1-4
Each component was mixed with a V-type blender in the proportions shown in Table 1, and then kneaded and pelletized at a cylinder temperature of 260 ° C. with a vent type twin screw extruder [Nikko Corporation, twin screw extruder TEX30α] with a screw diameter of 30 mm. . The obtained pellets were injection-molded with an injection molding machine [Sumitomo Heavy Industries, Ltd. SH100] at a cylinder temperature of 250 ° C. and a mold temperature of 60 ° C. to prepare test pieces (length 120 mm × width 120 mm × thickness 1 mm).

  Subsequently, the test piece (to-be-plated body) was plated in the following procedures. That is, a test piece degreased with a mixed solution of sodium borate, sodium phosphate and surfactant is pre-etched with an organic solvent, and further chemically etched with a mixed solution of chromic acid and sulfuric acid, and then hydrochloric acid and sulfuric acid. The neutralization process was performed using the liquid mixture. The obtained object to be plated was washed with water and subjected to electroless copper plating. The thickness of the electroless copper plating was 1 μm per side. After the electroless copper plating, nickel strike plating was further performed so that the thickness of the plating film including the electroless copper plating film was 15 μm or 50 μm per side.

  In the examples and comparative examples, the following components were used.

(i) PC: Commercially available aromatic polycarbonate resin having a viscosity average molecular weight of 25,000 (bisphenol A type polycarbonate resin)
(ii) ABS: ABS resin (rubber content 20% by weight, acrylonitrile content 20% by weight)
AAS: AAS resin (rubber content 20% by weight, acrylonitrile content 12% by weight)
AS: AS resin (acrylonitrile content 25% by weight, rubber content 0% by weight)
(iii) Inorganic filler:
F1: Wollastonite: number average fiber length 8.2 μm, number average fiber diameter 5.2 μm, number ratio of fiber length 5 to 25 μm with respect to the whole, aspect ratio 2
F2: Talc F3: Calcium carbonate whisker
(iv) Flame retardant: resorcinol bis (dixylenyl phosphate) (“Adeka Stub FP-500” manufactured by Asahi Denka Kogyo Co., Ltd.)
(v) Flame retardant aid: Polytetrafluoroethylene with ability to form fibrils (“6J” manufactured by Mitsui DuPont Fluorochemical Co., Ltd.)
(vi) Acid-modified PP: Acid-modified polypropylene resin (weight average molecular weight 3 × 10 ⁴ , number average molecular weight 1.5 × 10 ⁴ , melting point 145 ° C., maleic anhydride modified amount 10% by weight) (Sanyo Chemical Industries, Ltd.) "Umex 1010")
(vii) Thermal stabilizer: Phosphorus stabilizer Tris (2,4-di-t-butylphenyl) phosphite (“IRGAFOS168” manufactured by Ciba Geigy)
The results are shown in Table 1.

Claims (19)

  A plating coated body in which a plating film is formed on at least a part of the surface of a body to be plated formed of the thermoplastic resin composition, wherein the thermoplastic resin composition is a polycarbonate resin (A), The thermoplastic resin composition comprising a styrene resin (B) containing at least a rubber-containing styrene resin, an inorganic filler (C) that can be at least partially eluted by a mineral acid, and a flame retardant (D). The carbon fiber content is 5% by weight or less, and the ratio (weight ratio) between the polycarbonate resin (A) and the styrene resin (B) is polycarbonate resin (A) / styrene resin (B). When the average thickness of the object to be plated is 1.2 mm, the flame retardancy of the object to be plated according to UL-94 is V-1 or V-0. Plating covering.   The plated coating according to claim 1, wherein a plating film having a thickness of 10 to 100 μm is formed on the surface of the object to be plated.   2. The plating according to claim 1, wherein the bending elastic modulus is 5,000 to 50,000 MPa when the bending elastic modulus is measured in accordance with ISO178 for a plated covering using a plate-like object to be plated having a thickness of 1 mm. Covering.   In the cross-cut tape peeling test, 100 grid-like grids were formed at intervals of 1 mm. When the adhesive tape was adhered to the grid-like grids and peeled, 95 or more of the 100 grids were peeled off. The plating covering according to claim 1 which remains. The plated coating according to claim 1, wherein the polycarbonate resin (A) has a viscosity average molecular weight of 1.5 × 10 ^{4 to} 3 × 10 ⁴ .   Styrenic resin (B) is acrylonitrile-butadiene rubber-styrene resin, acrylonitrile-acrylic rubber-styrene resin, acrylonitrile-ethylenepropylene rubber-styrene resin, methyl methacrylate-butadiene rubber-styrene resin, butadiene rubber-styrene resin, and The plated coating according to claim 1, comprising at least one selected from these hydrogenated substances.   The plated coating according to claim 1, wherein the inorganic filler (C) is composed of at least one selected from particulate silicate, fibrous silicate, and whisker-like carbonate.   The plated coating according to claim 1, wherein the inorganic filler (C) is composed of at least one selected from talc, mica, wollastonite, and calcium carbonate whiskers.   The inorganic filler (C) is composed of a particulate or fibrous silicate having a silicon dioxide content of 35 to 55% by weight, and the proportion of the inorganic filler (C) is a polycarbonate resin (A ) And a styrene-based resin (B) in a total amount of 100 parts by weight, 5 to 50 parts by weight.   The plated coating according to claim 1, wherein the inorganic filler (C) is wollastonite having a number average fiber length of 1 to 30 µm, a number average fiber diameter of 0.1 to 10 µm, and an aspect ratio of 1.5 to 5.   The plated coating according to claim 1, wherein the flame retardant (D) is composed of a phosphorus-based flame retardant.   The plated coating according to claim 1, wherein the ratio of the flame retardant (D) is 1 to 50 parts by weight relative to 100 parts by weight of the total amount of the polycarbonate resin (A) and the styrene resin (B).   The plated coating according to claim 1, wherein the thermoplastic resin composition further comprises an acid-modified or epoxy-modified olefin compound (E).   The plating coating according to claim 13, wherein the acid-modified or epoxy-modified olefin compound (E) is an acid-modified or epoxy-modified olefin resin.   The plating coating according to claim 14, wherein the melting point of the acid-modified or epoxy-modified olefin resin is 100 to 170 ° C. The plated coating according to claim 14, wherein the acid-modified or epoxy-modified olefin resin has a weight average molecular weight of 1.5 × 10 ⁴ to 30 × 10 ⁴ .   The ratio of the acid-modified or epoxy-modified olefin compound (E) is 0.1 to 10 parts by weight with respect to 100 parts by weight of the total amount of the polycarbonate resin (A) and the styrene resin (B). Plating coating.   The plated coating according to claim 1, wherein when the average thickness of the object to be plated is 1.0 mm, the flame resistance of the object to be plated according to UL-94 is V-1 or V-0.   The plated coating according to claim 1, wherein when the average thickness of the object to be plated is 0.8 mm, the flame resistance of the object to be plated according to UL-94 is V-1 or V-0.