JPH064918B2 - Method for surface metallization of polyphenylene sulfide resin molded product - Google Patents

Description

TECHNICAL FIELD The present invention relates to an improved method of surface metallizing a polyphenylene sulfide resin molded article.

[Conventional technology]

Conventionally, as a method of metallizing the surface of a polyphenylene sulfide molded article, JP-B-56-25453 discloses that the metallized surface of the molded article is mechanically roughened, and then a chromium compound, sulfuric acid and A method has been proposed in which chemical plating is performed after etching with a strong oxidizing aqueous solution containing phosphoric acid as a main component.

[Problems to be Solved by the Present Invention]

However, in the method described in the above publication, the surface to be metallized needs to be mechanically roughened by sand blasting or sandpaper, so that it is difficult to apply it to a molded product having three-dimensional unevenness. There are drawbacks. Further, it is described in the publication that there is no roughening effect by subsequent treatment with a strongly oxidizing aqueous solution, but the adhesive force between the obtained metal plating film and the resin molded product is insufficient, and it can be said that this is an effective method. Absent.

Therefore, the present inventors have diligently studied a method for achieving a roughened surface of a polyphenylene sulfide resin molded product by chemical etching without performing a mechanical roughening treatment, and obtaining a sufficient adhesive force with a metal plating film. And then
Surface metallized polyphenylene sulfide resin with excellent plating adhesion by treating a molded product made by mixing a specific amount of a specific filler with polyphenylene sulfide resin in a specific chemical solution, and then performing ordinary plating. The present invention has been reached by finding that a molded product can be obtained.

[Means for solving problems]

That is, the present invention provides a polyphenylene sulfide resin 10
A polyphenylene sulfide resin molded article containing 10 to 250 parts by weight of an inorganic filler having an average particle size of 0.5 to 10 μm with respect to 0 parts by weight is used as anhydrous aluminum chloride, antimony pentachloride, or anhydrous ferric chloride. , Tellurium dichloride, tellurium tetrachloride, anhydrous stannic chloride, titanium tetrachloride,
After roughening treatment using a solution prepared by dissolving one or more selected from the group of Friedel-Crafts reaction catalysts such as bismuth trichloride and zinc chloride in an organic solvent,
It is intended to provide a method of surface metallizing a polyphenylene sulfide resin molded article, which is characterized by performing a plating treatment.

The polyphenylene sulfide used in the present invention (hereinafter referred to as PPS
Is abbreviated as) Is a polymer containing 70 mol% or more, more preferably 90 mol% or more, of the repeating unit represented by, and if the repeating unit is less than 70 mol%, heat resistance is impaired, which is not preferable.

PPS is generally a polymer having a relatively small molecular weight obtained by the production method represented by JP-B-45-3368 and an essentially linear polymer obtained by the production method represented by JP-B-52-12240. There are relatively high molecular weight polymers and the like, and in the former polymer, the polymerization degree is increased by heating after polymerization in an oxygen atmosphere or by adding a crosslinking agent such as peroxide and heating. It is also possible to use P obtained by any method in the present invention.
It is also possible to use PS. In terms of the mechanical properties of the molded product itself and in the sense of avoiding a decrease in the plating film adhesive strength due to the cohesive peeling of PPS on the plating adhesive surface, the production method represented by JP-B-52-12240. The essentially linear polymer obtained by can be more preferably used.

Further, PPS can comprise less than 30 mol% of its repeating unit with a repeating unit having the following structural formula.

The melt viscosity of the PPS used in the present invention is not particularly limited as long as it is possible to obtain a molded product, but the mechanical properties of the molded product are 100 poises or more, and the moldability is 10,000. Those having a poise or less are more preferably used.

Further, the PPS used in the present invention may be added with an antioxidant, a heat stabilizer, a copper damage inhibitor, a lubricant, a crystal nucleating agent, an ultraviolet absorber, and a coloring agent, and further controls the degree of crosslinking of PPS. For the purpose, conventional peroxides and JP-A-59-131650
Crosslinking accelerators such as metal thiophosphinic acid salts described in JP-A No. 58-204045, dialkyltin dicarboxylates described in JP-A No. 58-204046, aminotriazole and the like. It is also possible to add a crosslinking inhibitor.

As the inorganic filler used in the present invention, any of those soluble and insoluble in the chemical liquid used for the roughening treatment may be used, and it is not necessarily spherical, but the average particle diameter is
It is important to be in the range of 0.5 to 10 μ, more preferably 1 to 6 μ, and further preferably 1 to 3 μ. By using the filler having a particle diameter in this range, the uneven structure obtained by the roughening treatment has a size suitable for the anchor effect with the metal plating film, and a strong adhesion of the plating film can be obtained. If the average particle size is less than 1 μm or more than 10 μm, the adhesion of the plating film is small, which is not preferable, and if it exceeds 10 μm, the glitter of the plating is significantly impaired, which is not preferable. The average particle size here is
It is the particle size (medium number) at which the cumulative frequency obtained from the particle size distribution measured by the sedimentation balance method is 50%.

Examples of the inorganic filler used in the present invention include metal oxides such as alumina, silicon oxide, magnesium oxide, zirconia, and titanium oxide, calcium carbonate, magnesium carbonate, carbonates such as dolomite, calcium sulfate, and sulfuric acid such as barium sulfate. Salt, wollastonite, sericite, kaolin, mica, clay, bentonite, asbestos,
Examples thereof include, but are not limited to, silicates such as talc and alumina silicate, boron nitride, silicon carbide, and Saloyan. Two or more kinds of these fillers can be used in combination, and if necessary, they can be used after being pretreated with a coupling agent such as a silane-based or titanium-based coupling agent.

The blending amount of these inorganic fillers is preferably 10 to 250 parts by weight, and particularly preferably 30 to 100 parts by weight, based on 100 parts by weight of PPS. If it is less than 10 parts by weight, the effect of improving the adhesiveness of the metal plating film is insufficient, and if it exceeds 250 parts by weight, the surface roughness becomes large and the plating film adhesive strength and the glitter of the plating are impaired, which is not preferable.

Further, although not an essential component of the present invention, for the purpose of improving the mechanical properties of the molded product, if necessary, a fibrous reinforcing material such as glass fiber or carbon fiber may be added to 100 parts by weight of PPS as an essential component of the present invention. It is possible to mix the above inorganic filler and the fibrous reinforcing material in a range not exceeding 250 parts by weight. Further, a small amount of another type of polymer may be blended within a range that does not impair the object of the present invention.

The means for blending PPS with the inorganic filler and other additives is arbitrary and is not limited. For example, a method of simultaneous mixing with a screw extruder or the like can be adopted.

In the production of a molded product from the mixture, a usual thermoplastic resin molding means such as injection molding, extrusion molding, compression molding or blow molding can be arbitrarily adopted, and a molded product having a desired shape can be easily obtained. .

When carrying out the plating treatment in the present invention, it is important to first carry out a preliminary treatment such as wiping the oil film on the surface of the molded product, if necessary, and then to carry out a roughening treatment by the following method. Friedel-Crafts reaction catalysts used for roughening treatment include anhydrous aluminum chloride, antimony pentachloride, anhydrous ferric chloride, tellurium dichloride, tellurium tetrachloride, anhydrous stannic chloride, titanium tetrachloride, bismuth trichloride. , Zinc chloride, etc. Among them, anhydrous aluminum chloride, antimony pentachloride, anhydrous ferric chloride, and tellurium dichloride are more preferably used, and most preferably anhydrous aluminum chloride is used, from the viewpoint of roughening efficiency. The organic solvent that dissolves these catalysts is not particularly limited as long as it can dissolve the catalyst, but usually, benzene, toluene, xylene and the like and mixtures thereof are preferably used, and toluene is used in the sense of safety of operation. More preferably used. The ratio of the catalyst to be dissolved in an organic solvent is not particularly limited, but usually 5 to 20 g of chloride is selected with respect to 100 cc of the organic solvent.

The conditions for roughening the surface of the PPS molded product with an organic solvent in which a catalyst is dissolved (hereinafter abbreviated as an etching solution) vary depending on the type of catalyst, the type of organic solvent, and a combination thereof, but in order to accelerate the processing speed. For this purpose, it is effective to heat the etching solution. For example, in the case of an etching solution having a ratio of 10 g of anhydrous aluminum chloride to 100 cc of toluene, a good roughened state can be obtained by immersing the molded product in the temperature range of 60 to 80 ° C. for 30 seconds to 3 minutes. Further, for the purpose of improving the uniformity of the roughened state between the parts of the molded product, it is preferable to move or rotate the molded product in the etching solution, or to immerse the molded product while stirring the etching solution.

When performing the plating treatment subsequent to the above roughening treatment, it is preferable to thoroughly wash the plated surface of the molded product with water or the like, and in the case where the PPS decomposed matter remains on the plated surface, ultrasonic waves are applied. It is effective to use a method such as washing.

By subjecting the resin molded article for plating thus roughened to a known plating treatment, the surface metallized P is excellent in the adhesiveness of the plating film and the glitter of the plating.
A PS resin molded product is obtained. It is also possible to metallize the surface of the roughened surface-treated product by metal vapor deposition, sputtering or the like.

The plating treatment includes, for example, sensitizing with a stannous chloride solution, activating with a palladium chloride solution, electroless plating of copper or nickel, or catalisting-accelerating-electroless plating. It is possible to apply a normal plating method which is performed by further performing electroplating and additionally performing electroplating with the same or different kind of metal as the electroless plated metal.

Further, in performing the plating treatment, by partially shielding the surface of the resin molded product for plating by a commonly known method,
It is also possible to obtain a molded product with a partially metallized surface.

Furthermore, the molded article produced by the method of the present invention can be subjected to heat treatment at a temperature below the melting point of PPS for the purpose of increasing the degree of crystallinity or the degree of crosslinking during any of the steps after molding. It is also possible to perform heat treatment after the treatment for the purpose of increasing the adhesive strength of the plated film. The heat treatment of the formed product at a temperature of 100 to 130 ° C. after plating is particularly effective for increasing the adhesive strength of the plated film.

Hereinafter, the present invention will be described in more detail with reference to examples.

〔Example〕

Examples 1-12, Comparative Examples 1-4 Melt viscosity 1,200 poise (320 ° C, shear rate 1,0)
00 sec- ¹ ) 100 parts by weight of powdered PPS ("Ryton" P-4, manufactured by US Phillips Petroleum Co., Ltd.) and various inorganic fillers shown in Table 1 were dried at the ratios shown in Table 1.・ Blend, melt-mixed by a screw extruder set at 310 ° C., taken in strands, and pelletized by a strand cutter.

Next, each pellet was supplied to a screw in-line type injection molding machine set at 310 to 320 ° C., and a mold temperature of 130 to
Under conditions of 140 ℃, one side is 80mm square and the thickness is about 3
mm test pieces were molded.

Next, 50 g of anhydrous aluminum chloride is added to toluene of 500 g.
Each test piece was immersed in an etching solution dissolved in cc and heated at 80 ° C. for 1 minute while stirring the solution for roughening treatment. These test pieces were washed with ethanol, acetone, and water, further ultrasonically washed in water, and then subjected to plating treatment by sequentially performing the following steps.

(1) Catalisting A-30 catalyst (manufactured by Okuno Chemical Industries Co., Ltd.) was immersed in a solution at 25 ° C. for 3 minutes.

(2) Washing with water (3) Accelerating The sample was immersed in a 10% sulfuric acid solution at 40 ° C for 3 minutes.

(4) Washing with water (5) Electroless copper plating 100 g of copper sulfate (CuSO ₄ .5H ₂ O) and 400 cc of a 35% aqueous solution of formalin were diluted with water to make a plating solution A and potassium sodium tartrate (tetrahydrate). Material) 400 g and 100 g of sodium hydroxide were diluted with water to make a plating solution B, 200 cc of each was mixed just before use and diluted with water to a plating solution of 2 and immersed in air for 8 minutes at room temperature while bubbling air. Processed.

(6) Washing with water (7) Electroplating Test pieces plated with electroless plating were concentrated sulfuric acid 50 g, copper sulfate (pentahydrate) 200 g, and SCB-MU10 as a brightener.
cc, SCB-11cc, (Okuno Pharmaceutical Co., Ltd.) and 1,000 cc of water are placed in an acidic copper plating bath at a temperature of about 25 ° C. and a current density of 3 A / dm ² for 15 minutes, then 12 A / d.
Electroplating was performed at m ² for 9 minutes to form a copper plating film having a thickness of about 50 μm. With respect to the obtained surface metallized PPS molded product, the result of evaluating the force required for T-peeling the plating film over the width of 10 mm and the length of 40 mm as the adhesion of the plating film and the evaluation result of the plating glittering property are shown in Table 1. Shown in.

For the evaluation of plating glittering property, a fluorescent lamp was projected on the plated surface of an 80 × 80 mm square plate, and the image was visually observed, and when the reflected image of the fluorescent lamp was clearly visible with good contrast, it was “good” (○). When the boundary surface of the reflected image was slightly blurred, it was judged as "slightly good" (△), and when the entire reflected image was blurred and unclear, it was judged as "bad" (x).

Example 13 For the test piece used in Example 3, an etching solution prepared by dissolving 50 g of anhydrous aluminum chloride in 500 cc of xylene was used in place of the roughening treatment with a toluene solution of anhydrous aluminum chloride, and the solution temperature was 90 ° C. Except for the above, the same operation as in Example 3 was carried out to obtain the surface metallized PPS.
A molded product was obtained. When the adhesive strength of the plating film was evaluated 1,
It was 790 g / cm.

Example 14 For the test piece used in Example 3, an etching solution prepared by dissolving 50 g of antimony pentachloride in 500 cc of toluene was used instead of the roughening treatment with a toluene solution of anhydrous aluminum chloride, and the immersion time was 2 minutes. Except for the above, the same operation as in Example 3 was carried out to obtain a surface-metallized PPS molded product. The adhesive strength of the plating film was 1,650 g / cm.

Comparative Examples 5 to 10 Except that the test pieces used in Examples 3 and 8 were subjected to the following respective treatments instead of the rough surface treatment with a toluene solution of anhydrous aluminum chloride, the test specimens were completely different from those of Example 3. The plating treatment was carried out by the same operation and the adhesion of the plating film was evaluated. The results are shown in Table 2.

(1) Chromium mixed acid treatment A test piece was immersed in a mixed solution of 162 g of potassium dichromate, 390 cc of concentrated sulfuric acid, 99 cc of concentrated phosphoric acid and 999 cc of water at 50 ° C for 3 minutes.

(2) Nitric acid treatment A test piece was immersed in 60% nitric acid at 30 ° C for 5 minutes, washed with water, and further neutralized with a 10% sodium carbonate solution.

(3) Sulfuric acid treatment The test piece was immersed in concentrated sulfuric acid at 150 ° C for 5 minutes, washed with water, and further neutralized with a 10% sodium carbonate solution.

Example 15 Instead of the pellets used in Example 1, 40 parts by weight of titanium oxide having an average particle size of 2.3 μ and 100 parts by weight of PPS and glass fiber (TN-100 manufactured by Nippon Electric Insulator Co., Ltd.) 40
A surface metallized PPS molded product was obtained in the same manner as in Example 1 except that the pellets obtained by melting and mixing parts by weight were used. The resulting molded product had a good plating glitter and a plating film adhesion of 1,450 g / cm.

Example 16 A surface metallized PPS molded product was obtained in exactly the same manner as in Example 3, except that the PPS obtained by the method shown in Reference Example 1 was used instead of the PPS used in Example 3. It was

The resulting molded product had good plating glitter and had a plating film adhesive strength of 1,870 g / cm.

Reference Example 1 (Preparation of PPS) 3.26 kg of sodium sulfide (25 mol, containing 40% of water of crystallization), 4 g of sodium hydroxide, 1.36 kg (about 10 mol) of sodium acetate trihydrate and N-methyl-in an autoclave. 2-pyrrolidone (hereinafter referred to as NMP) 7.9 kg was charged, and the temperature was gradually raised to 205 ° C. with stirring, and water 1.36 was added.
Distilled water 1.50 containing kg was removed. 1,4-
3.75 kg (25.5 mol) of dichlorobenzene and 2 kg of NMP were added, and the mixture was heated at 265 ° C for 4 hours. The reaction product was washed with hot water eight times and dried under reduced pressure at 80 ° C. for 24 hours to obtain about 2 kg of powdery PPS having a melt viscosity of 2,500 poise.

Comparative Example 11 Instead of the PPS used in Comparative Example 5, P used in Example 15 was used.
A surface metallized PP was prepared in the same manner as in Comparative Example 5 except that PS (prepared by the method of Reference Example 1) was used.
An S molded product was obtained. The resulting molded product has a plating film adhesion of 2
It was 30 g / cm.

Example 17 Using the pellets of the PPS composition used in Example 3, a box-shaped molded product having a width of 50 mm, a length of 80 mm, a height of 35 mm and a thickness of 2.5 mm was molded, and the test piece used in Example 3 was manufactured. The plating treatment was carried out by the same operation except that this molded product was used instead of. The appearance of the obtained molded product was good.

〔The invention's effect〕

Since the surface metallizing method of the polyphenylene sulfide resin molded article of the present invention is performed without passing through the step of mechanical roughening treatment, it is possible to surface metallize the surface of the three-dimensional uneven structure. The surface metallized polyphenylene sulfide resin molded product obtained by the method of the present invention has excellent plating film adhesion, surface glitter and excellent heat resistance, chemical resistance and mechanical properties derived from PPS, and is used as a metal substitute. It is useful as various parts such as and printed wiring boards.

Claims (1)

[Claims] 1. A polyphenylene sulfide resin molded article containing 10 to 250 parts by weight of an inorganic filler having an average particle diameter of 0.5 to 10 μm per 100 parts by weight of a polyphenylene sulfide resin.
Selected from the group of Friedel-Crafts reaction catalysts consisting of antimony pentachloride, anhydrous ferric chloride, tellurium dichloride, tellurium tetrachloride, stannic chloride anhydrous, titanium tetrachloride, bismuth trichloride, zinc chloride, etc. A method of surface metallizing a polyphenylene sulfide resin molded article, which comprises subjecting a surface of a polyphenylene sulfide resin molded article to a roughening treatment using a solution prepared by dissolving one or more kinds in an organic solvent, and then performing a plating treatment.