JP2006328134A - Resin composition for direct metal plating and metal-plated ornamental product - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resin composition for direct metal plating excellent in balance between metal plating precipitation and metal plating adhesiveness in an electric copper plating process of PC/ABS-based resins in a direct metal plating method and in resin characteristics such as impact resistance, heat resistance and the like. <P>SOLUTION: The resin composition for direct metal plating comprises 20-80 wt.% polycarbonate resin (A) and 80-20 wt.% rubber-reinforced styrene-based resin (B). In 100 pts.wt. composition, the rubber-reinforced styrene-based resin (B) comprises 20-99 wt.% rubber-reinforced styrene-based resin (b-1) comprising an ethylene-propylene-based rubbery polymer as a constituent ingredient and 1-80 wt.% rubber-reinforced styrene-based resin (b-2) comprising a conjugated diene-based rubbery polymer as a constituent ingredient. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention relates to a resin composition for direct plating comprising a polycarbonate resin and a rubber-reinforced styrene resin. Specifically, as the rubber-reinforced styrene resin, a rubber-reinforced styrene resin having an ethylene-propylene rubber-like polymer as a constituent component and a rubber-reinforced styrene resin having a conjugated diene rubber-like polymer as a constituent component. Resin composition for direct plating excellent in resin performance such as direct plating properties, particularly the balance between plating deposition properties and plating adhesion strength in the electrolytic copper plating process, impact resistance, and heat resistance, and the resin composition It is related with the plating decoration product formed by giving direct plating to the resin molded product formed by shape | molding.

A composition comprising a polycarbonate resin and an ABS resin (hereinafter referred to as a PC / ABS resin) has excellent impact resistance, heat resistance, and molding processability. Therefore, it is suitable for vehicle parts, home appliances, and office equipment parts. It is used for various purposes including the beginning. In particular, there is a tendency for vehicle parts and the like to increase in size, and the shape tends to be more complicated. In addition, in order to reduce the weight of the vehicle, the thickness of the molded product tends to be designed to be thinner, so a material having excellent properties such as molding processability, impact resistance, and heat resistance is required. There is a case where PC / ABS resin is adopted as one of the options.
In addition, in these applications, there are many examples in which decorative plating is applied to PC / ABS resins for parts that have a metallic appearance and are required to be lightweight. Conventionally, the plating process of PC / ABS resin generally includes degreasing, chemical etching, neutralization, catalyst application, activation, electroless plating, acid activation, electroplating, and so-called catalyst-accelerator method. Is the mainstream. However, in the electroless plating solution used in this method, for example, the electroless nickel plating solution contains hypophosphite as a reducing agent, but this hypophosphite affects environmental problems. However, there is a problem that wastewater regulation is very strict because of the high COD waste liquid corresponding to phosphorus regulation, and the cost of wastewater treatment becomes very high. In addition, deterioration of the working environment due to ammonia odor used for pH adjustment is also a problem. Similarly, formalin is used as a reducing agent in the electroless copper plating solution. However, the use of formalin has been pointed out to have adverse effects on various health and environmental problems. Furthermore, since this plating solution uses a powerful complexing agent for solubilizing copper ions in an alkaline solution, the cost of wastewater treatment is extremely high for removing metal ions in the wastewater treatment of the plating solution. It has various problems such as high.

In order to meet the health and global environmental laws and regulations and to ensure a safe working environment in these catalyst-accelerator methods, do not use electroless plating baths as part of plating method improvement. Plating methods (called direct plating methods, direct plating methods, etc.) are being studied for practical use. For example, a Pd—Sn colloid catalyst method is disclosed in Japanese Patent Laid-Open Nos. 7-11487 (Patent Document 1), 11-61425 (Patent Document 2), and the like.

The PC / ABS resin used in the conventional resin plating method is also generally used in these direct plating methods, but the PC / ABS resin is a molded product in the electrolytic copper plating process of the direct plating method. There is a tendency that plating does not easily deposit on the surface, and an unattached portion of plating expressed as skipping tends to occur, and particularly in a molded product having a complicated product shape, there is a problem that the tendency becomes extremely high.
JP-A 2003-327817 (Patent Document 3) proposes a resin composition for direct plating comprising an ABS resin and PC using two types of rubbery polymers having different particle diameters. In addition, since it is necessary to produce rubbery polymers each having a desired particle size, the production process is complicated, and in particular, there is a problem that a great deal of labor is required to produce a rubbery polymer having a large particle size. Further, the plating precipitation was not satisfactory.
JP-A-7-11487 Japanese Patent Laid-Open No. 11-61425 JP 2003-327817 A

An object of the present invention is to provide a resin composition for direct plating excellent in direct plating properties, particularly a balance between plating deposition properties and plating adhesion strength in an electrolytic copper plating process, and resin performance such as impact resistance and heat resistance. is there.

As a result of intensive studies on the above problems, the present inventors unexpectedly satisfy these performances only by using a rubber-reinforced styrene resin containing PC and two specific types of rubbery polymers as constituent components. The present invention has been found.
That is, in the present invention, in 100 parts by weight of a composition comprising 20 to 80% by weight of a polycarbonate resin (A) and 80 to 20% by weight of a rubber-reinforced styrene resin (B), the rubber-reinforced styrene resin (B) 20 to 99% by weight of rubber-reinforced styrene resin (b-1) containing ethylene-propylene rubber-like polymer as a constituent and rubber-reinforced styrene resin (b-2) containing conjugated diene rubber-like polymer as a constituent ) A resin composition for direct plating comprising 1 to 80% by weight is provided.

The effect of obtaining a resin composition for direct plating excellent in resin performance such as the balance of plating deposition and plating adhesion strength in the electrolytic copper plating process, impact resistance, heat resistance, etc. of PC / ABS resin in direct plating method. Play.

Hereinafter, the present invention will be described in detail.
The polycarbonate resin (A) used in the present invention is a phosgene method in which various dihydroxydiaryl compounds and phosgene are reacted, or a transesterification method obtained by reacting a dihydroxydiaryl compound and a carbonate such as diphenyl carbonate. Typical examples of the coalescence include 2,2-bis (4-hydroxyphenyl) propane; polycarbonate resin produced from “bisphenol A”.

Examples of the dihydroxydiaryl compound include bisphenol A, bis (4-hydroxydiphenyl) methane, 1,1-bis (4-hydroxyphenyl) ethane, 2,2-bis (4-hydroxyphenyl) butane, 2, 2-bis (4-hydroxyphenyl) octane, bisbis (4-hydroxydiphenyl) phenylmethane, 2,2-bis (4-hydroxydiphenyl-3-methylphenyl) propane, 1,1-bis (4-hydroxy-3) -Tert-butylphenyl) propane, 2,2-bis (4-hydroxy-3-bromophenyl) propane, 2,2-bis (4-hydroxy-3,5dibromophenyl) propane, 2,2-bis (4 Bis (hydroxyaryl) alkanes such as -hydroxy-3,5-dichlorophenyl) propane; , 1-bis (4-hydroxyphenyl) cyclopentane, bis (hydroxyaryl) cycloalkanes such as 1,1-bis (4-hydroxyphenyl) cyclohexane, 4,4′-dihydroxydiphenyl ether, 4,4′- Dihydroxy diaryl ethers such as dihydroxy-3,3′-dimethyldiphenyl ether, 4,4′-dihydroxydiphenyl sulfide, dihydroxydiaryl sulfides such as 4,4′-dihydroxy-3,3′-dimethyldiphenyl sulfide Dihydroxy diaryl sulfoxides such as 4,4'-dihydroxydiphenyl sulfoxide, dihydro such as 4,4'-dihydroxydiphenyl sulfone, 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfone Siji aryl sulfones and the like.

These may be used alone or in combination of two or more. In addition to these, piperazine, dipiperidyl hydroquinone, resorcin, 4,4′-dihydroxydiphenyls, and the like may be mixed.

Further, the above-mentioned dihydroxydiaryl compound and a trivalent or higher valent phenol compound as shown below may be mixed and used. Trihydric or higher phenols include phloroglucin, 4,6-dimethyl-2,4,6-tri- (4-hydroxyphenyl) -heptene-2,4,6-dimethyl-2,4,6-tri- (4 -Hydroxyphenyl) -heptane, 1,3,5-tri- (4-hydroxyphenyl) -benzol, 1,1,1-tri- (4-hydroxyphenyl) -ethane and 2,2-bis- (4 4 '-(4,4'-hydroxydiphenyl) cyclohexyl) -propane and the like. In addition, when manufacturing these polycarbonate resins, a molecular weight regulator, a catalyst, etc. can be used as needed.

The rubber-reinforced styrene-based resin (B) used in the present invention is a rubber-reinforced styrene-based resin (b-1) and a conjugated diene-based rubber-like polymer having an ethylene-propylene rubber-like polymer as a constituent component. It is a mixture comprising a rubber-reinforced styrene resin (b-2) as a constituent component.

Examples of the ethylene-propylene rubber-like polymer constituting the rubber-reinforced styrene resin (b-1) used in the present invention include ethylene-propylene copolymer rubber, ethylidene norbornene, dicyclopentadiene, 1,4. -Ethylene-propylene-nonconjugated diene copolymer rubber obtained by introducing a nonconjugated diene component such as hexadiene. In particular, it is preferable to use those having an ethylene content of 30 to 80% by weight and a Mooney viscosity (ML1 + 4 121 ° C.) of 40 to 80.

Examples of the conjugated diene rubbery polymer constituting the rubber-reinforced styrene resin (b-2) used in the present invention include polybutadiene, styrene-butadiene copolymer, acrylonitrile-butadiene copolymer, and styrene- Examples thereof include a butadiene block polymer. In particular, the weight average particle diameter of the conjugated diene rubber-like polymer dispersed in the rubber-reinforced styrene resin (b-2) is 0.1 to 0.8 μm from the balance of plating precipitation and adhesion strength. Is preferred.

The rubber-reinforced styrene resins (b-1) and (b-2) are each composed of a rubber-like polymer, an aromatic vinyl compound, and another vinyl compound that can be copolymerized.

Examples of the aromatic vinyl compound used in the present invention include styrene and α-methylstyrene, and these can be used alone or in combination.
Examples of other copolymerizable vinyl compounds include vinyl cyanide compounds such as acrylonitrile and methacrylonitrile, (meth) acrylic acid ester compounds such as methyl methacrylate and methyl acrylate, maleimide, and N-phenylmaleimide. Such as maleimide compounds, unsaturated carboxylic acids such as acrylic acid, methacrylic acid, itaconic acid and maleic acid, unsaturated carboxylic acid anhydrides such as maleic anhydride and itaconic anhydride, and unsaturated such as glycidyl methacrylate and allyl glycidyl ether Examples thereof include hydroxyl group-containing unsaturated compounds such as epoxy compounds, hydroxyethyl acrylate, and hydroxyethyl methacrylate, which can be used alone or in combination of two or more.

  There are no particular restrictions on the composition ratios of the components constituting the rubber-reinforced styrene resins (b-1) and (b-2), but 10 to 80% by weight of the rubber-like polymer and 20 to 20% of the aromatic vinyl compound, respectively. 100% by weight and 90% to 20% by weight of a compound (total) consisting of 0 to 80% by weight of other compounds copolymerizable, particularly 10 to 80% by weight of a rubbery polymer and an aromatic vinyl compound 20 to 90% by weight and a compound (total) of 90 to 20% by weight consisting of 10 to 80% by weight of a vinyl cyanide compound and / or a (meth) acrylic acid ester compound as another copolymerizable compound. preferable.

The resin composition for direct plating in the present invention comprises 20 to 80% by weight of the polycarbonate resin (A) and 80 to 20% by weight of the rubber-reinforced styrene resin (B), but the polycarbonate resin (A) is 20% by weight. If it is less than%, heat resistance and impact resistance are lowered, and if it exceeds 80% by weight, plating deposition and molding processability are not preferred.

The rubber-reinforced styrene resin (B) is composed of 20 to 99% by weight of rubber-reinforced styrene resin (b-1) containing ethylene-propylene rubber-like polymer as a constituent and conjugated diene rubber-like polymer as a constituent. The rubber-reinforced styrene-based resin (b-2) is 1 to 80% by weight, but if the rubber-reinforced styrene-based resin (b-1) is less than 20% by weight, the plating adhesion strength and the heat cycle property are lowered. In addition, when the rubber-reinforced styrene resin (b-2) exceeds 80% by weight, the plating deposition property and the skip property are deteriorated, which is not preferable.

  In the present invention, if necessary, styrene-acrylonitrile copolymer (AS), α-methylstyrene-acrylonitrile copolymer (αMS-ACN), methyl methacrylate-styrene copolymer (MS), methacrylic acid. Other styrenes such as methyl-acrylonitrile-styrene copolymer (MAS), styrene-N-phenylmaleimide copolymer (S-NPMI), styrene-N-phenylmaleimide-acrylonitrile copolymer (SA-NPMI) The copolymer may be blended as a part of the rubber-reinforced styrene resin (B), and further, an antioxidant, an ultraviolet absorber, a light stabilizer, an antistatic agent, a lubricant, a dye, a pigment, a plasticizer, Known additives such as flame retardants and release agents, reinforcing materials, fillers, and the like can be added.

The resin composition for direct plating obtained above is molded by a known molding method such as injection molding, extrusion molding, compression molding, injection compression molding, blow molding, etc., and the resin molded product obtained is a direct plating method. The effect of the present invention is expressed as a plated decorative product.
Note that the direct plating method of the present invention is not particularly limited as long as it is a plating method that does not use an electroless plating process in consideration of compliance with laws and regulations relating to health and the global environment, and ensuring a safe working environment. There is no limit.

〔Example〕
EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited by these. In addition, the part and% which are shown in an Example are based on a weight.

Polycarbonate resin (A): Polycarbonate resin composed of phosgene and bisphenol A and having a viscosity average molecular weight of 20,500.

Rubber reinforced styrene resin (B)
Rubber-reinforced styrene resin (b-1): a copolymer comprising 30 parts of ethylene-propylene rubber as a rubbery polymer dispersed in the resin by a known suspension polymerization method, and comprising 49 parts of styrene and 21 parts of acrylonitrile. Manufactured.
Rubber-reinforced styrene resin (b-2): containing 30 parts of polybutadiene (weight average particle size 0.36 μm) as a rubbery polymer dispersed in the resin by a known emulsion polymerization method, 49 parts of styrene and 21 parts of acrylonitrile A copolymer consisting of
Rubber Reinforced Styrene Resin (bi): Contains 40 parts of polybutadiene (weight average particle diameter 0.8 μm (enlarged treatment)) as a rubbery polymer dispersed in the resin by a known emulsion polymerization method, and styrene 42 And a copolymer consisting of 18 parts of acrylonitrile.

[Examples 1-4 and Comparative Examples 1-4]
The polycarbonate resin (A) and the rubber-reinforced styrene resin (B) are mixed at the blending ratio shown in Table 1, and melt mixed at a cylinder temperature of 250 to 270 ° C. using a 50 mm extruder (manufactured by ON Machinery). Pelletized. About the obtained pellet, various test pieces were created with an injection molding machine, and impact resistance, heat resistance, molding processability, plating adhesion strength, plating deposition property, and heat cycle property were measured.

Impact resistance: ASTM
A notched Izod impact test was measured according to D-256. 1/4 inch, 23 ° C. (unit: J / m).

Heat resistance: ASTM
Conforms to D-648. 1/4 inch, no annealing, 1.82 MPa load (unit: ° C.).

Formability: ASTM
The melt flow rate was measured according to D-1238. Measurement conditions: 250 ° C., 10 kg (unit: g / 10 min).

Plating adhesion strength: After forming a flat plate product for plating (55 × 90 × 3 mm) with an injection molding machine and performing direct plating by the following method, the adhesion strength of the deposited plating film is determined according to JIS H-8630. Based on the above, cuts at intervals of 1 cm reaching the substrate were made in the metal film of the plated product, and the stress (N) when the metal film was peeled off in the vertical direction was shown.
<Plating treatment step> The above plate for plating was immersed in a CRP cleaner at 40 ° C for 3 minutes for degreasing. The degreased flat plate was washed with water at 30 ° C. and then immersed in an etching solution at 67 ° C. (chromic acid: 400 g / l, sulfuric acid: 200 cc / l) for 10 minutes for etching. The etched flat plate was washed with water at 30 ° C. for 2 minutes and then immersed in a CRP reducer at 25 ° C. for 3 minutes for neutralization. The neutralized flat plate is washed with water at 30 ° C. for 2 minutes, pre-dip in hydrochloric acid at 25 ° C. for 1 minute, and then immersed in a CRP catalyst at 35 ° C. for 6 minutes to perform Pd—Sn colloid catalysis treatment. It was. After the catalyzed flat plate was washed with water at 30 ° C. for 2 minutes, it was immersed in 45 ° C. CRP selectors A and B for 3 minutes to conduct a conductor. After the conductor-treated flat plate was washed with water at 30 ° C. for 2 minutes, a current density of 3 A / dm ² was applied to an electrolytic copper plating bath using a CRP copper at 25 ° C. for 2 hours, and the film thickness was 50 μm. An electrolytic copper plating film was deposited on a flat plate. The plate after electrolytic copper plating was washed with water at 30 ° C., and then the flat plate plated with copper was aged at 80 ° C. for 2 hours and allowed to stand overnight.

Plating precipitation: A flat plate product for plating (55 × 90 × 3 mm) is formed by an injection molding machine, and a corrugated flat plate is formed by alternately inserting left and right cuts of 1 mm in width and 45 mm in length in the short side direction every 9 mm in the long side direction. After creating and direct plating by the following method, the degree of deposition of the plating film, the length of the plating film deposited on the corrugated flat plate: the number of steps of the corrugated flat plate, and the unplated portion in the deposition process (skip) The degree of occurrence was visually determined and determined according to the following criteria. ○: Good without skipping. Δ: A state where a part of the skip is seen. X: Skip is seen overall and is poor.
<Plating treatment step> The above plate for plating was immersed in a CRP cleaner at 40 ° C for 3 minutes for degreasing. The degreased flat plate was washed with water at 30 ° C. and then immersed in an etching solution at 67 ° C. (chromic acid: 400 g / l, sulfuric acid: 200 cc / l) for 10 minutes for etching. The etched flat plate was washed with water at 30 ° C. for 2 minutes and then immersed in a CRP reducer at 25 ° C. for 3 minutes for neutralization. The neutralized flat plate is washed with water at 30 ° C. for 2 minutes, pre-dip in hydrochloric acid at 25 ° C. for 1 minute, and then immersed in a CRP catalyst at 35 ° C. for 6 minutes to perform Pd—Sn colloid catalysis treatment. It was. After the catalyzed flat plate was washed with water at 30 ° C. for 2 minutes, it was immersed in 45 ° C. CRP selectors A and B for 3 minutes to conduct a conductor. After the conductive plate was washed with water at 30 ° C. for 2 minutes, an electric copper plating film was energized at 25 ° C. for 5 minutes with a current density of 2 A / dm ² in an electrolytic copper plating bath using a CRP copper. Was deposited on a flat plate.

Heat cycle property: A flat plate molded product for plating (55 × 90 × 3 mm) and a frame mold molded product are molded by an injection molding machine, and after direct plating is performed by the following method, −30 ° C. (1 hr) → Ten cycles of 23 ° C. (0.5 hr) → 80 ° C. (1 hr) → 23 ° C. (0.5 hr) were carried out, and the presence or absence of abnormalities such as swelling was visually confirmed on the appearance of each plated product.
<Plating treatment step> The above plate for plating was immersed in a CRP cleaner at 40 ° C for 3 minutes for degreasing. The degreased flat plate was washed with water at 30 ° C. and then immersed in an etching solution at 67 ° C. (chromic acid: 400 g / l, sulfuric acid: 200 cc / l) for 10 minutes for etching. The etched flat plate was washed with water at 30 ° C. for 2 minutes and then immersed in a CRP reducer at 25 ° C. for 3 minutes for neutralization. The neutralized flat plate is washed with water at 30 ° C. for 2 minutes, pre-dip in hydrochloric acid at 25 ° C. for 1 minute, and then immersed in a CRP catalyst at 35 ° C. for 6 minutes to perform Pd—Sn colloid catalysis treatment. It was. After the catalyzed flat plate was washed with water at 30 ° C. for 2 minutes, it was immersed in 45 ° C. CRP selectors A and B for 3 minutes to conduct a conductor. After the conductive plate was washed with water at 30 ° C. for 2 minutes, a current density of 2 A / dm ² was applied to an electrolytic copper plating bath using a CRP copper at 25 ° C. for 15 minutes to obtain 15 μm electrolytic copper. The plating film was deposited on a flat plate. Subsequently, in a general decorative electroplating process, a semi-bright nickel film: 6 μm, a bright nickel film: 4 μm, and a chromium plating film: 0.1 to 0.3 μm were deposited.

These measurement results are shown in Table 1.

The resin composition of the present invention is for direct plating excellent in resin performance such as the balance of plating precipitation and plating adhesion strength in the electrolytic copper plating process, impact resistance, heat resistance, etc. of the PC / ABS resin in the direct plating method. It is a resin composition, and a plated decorative product having the above-mentioned performance obtained by direct plating on a resin molded product obtained by molding the resin composition is obtained, and has high industrial utility value.

Claims (4)

In 100 parts by weight of a composition comprising 20 to 80% by weight of a polycarbonate resin (A) and 80 to 20% by weight of a rubber reinforced styrene resin (B), the rubber reinforced styrene resin (B) is an ethylene-propylene rubber 20 to 99% by weight of rubber-reinforced styrene resin (b-1) containing a polymer as a constituent and 1 to 80% by weight of rubber-reinforced styrene resin (b-2) containing a conjugated diene rubber-like polymer as a constituent A resin composition for direct plating, comprising: The resin composition for direct plating according to claim 1, wherein the rubber-reinforced styrene resin (B) is composed of a rubber-like polymer, an aromatic vinyl compound, and another vinyl compound capable of copolymerization. The resin for direct plating according to any one of claims 1 to 2, wherein the conjugated diene rubber-like polymer dispersed in the rubber-reinforced styrene resin (b-2) has a weight average particle diameter of 0.1 to 0.8 µm. Composition. A plated decorative product obtained by subjecting a resin molded product obtained by molding the resin composition according to claim 1 to direct plating.