JPS6113497B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a plating resin composition that can be electroplated directly onto molded articles without chemically plating them. Conventionally, the method of directly electroplating was to add carbon black and sulfur etc. to a base mainly made of rubber to give it conductivity, but since it is mainly made of rubber, it lacks rigidity and also requires the use of sulfur. Therefore, in order to increase the adhesion with the plating metal, it is necessary to ripen it in the air or under certain environmental conditions for several days, which caused various problems such as sulfur blooming during aging or storage. . Furthermore, since the molded product is mainly made of rubber, sink marks or pinholes are likely to occur in the molded product, and even if the molded product is plated, the defects will continue to appear. The present invention solves these problems and further increases the adhesion of plating. That is, the present invention provides a direct electroplating method characterized in that 15 to 50 parts by weight of carbon black, 0.05 to 5 parts by weight of sulfur, and 1 to 15 parts by weight of metal powder or metal sulfide are blended with 100 parts by weight of thermoplastic resin. The object of the present invention is to provide a resin composition that is possible. Thermoplastic resins in the present invention include polyethylene, polypropylene, ethylene propylene copolymer, ethylene propylene diene terpolymer, ethylene vinyl acetate copolymer, polyvinyl chloride, polystyrene, polyacetal, 6,6-6,6-
Polyamides such as 10, 6-12, 11, 12, polyphenylene sulfide (PPS), polyphenylene oxide (PPO), polybutylene terephthalate (PBT), polyethylene terephthalate (PET),
Includes ABS, AS, polymethylpentene, styrene-butadiene-styrene copolymer (SBS), polycarbonate, etc. Carbon blacks include acetylene black, furnace black, channel black,
Ketuchen black etc. are used. Metal powders include nickel, iron, zinc, chromium, copper, aluminum, etc. Metal sulfides include zinc sulfide, antimony sulfide, aluminum sulfide, gold sulfide, silver sulfide, chromium sulfide, lead sulfide, strontium sulfide, tin sulfide, and sulfide. Titanium, iron sulfide, copper sulfide, nickel sulfide, vanadium sulfide, palladium sulfide, barium sulfide, cadmium sulfide, bismuth sulfide, arsenic sulfide, boron sulfide, beryum sulfide, magnesium sulfide, manganese sulfide, etc. are used. The carbon black blended in the present invention imparts conductivity to the thermoplastic resin, and the conductivity improves as the amount increases, but based on 100 parts by weight of the thermoplastic resin.
If it exceeds 50 parts by weight, not only will the fluidity deteriorate and molding become difficult, but also the impact resistance and appearance of plating will deteriorate. If the amount is less than 15 parts by weight, the conductivity will not be improved and electroplating will not be possible. Next, the addition of sulfur is essential for improving the adhesion strength of plating, but it produces an odor during the manufacturing process of the molding material or during molding, making it undesirable during work. When stored, sulfur blooms on the surface of the molded product, and when it is subsequently plated, the appearance of the plated product deteriorates significantly. However, the inventors of the present invention have found through research that the combined use of metal powder or metal sulfide eliminates the odor during work and lengthens the number of days in which sulfur blooming occurs. That is, sulfur per 100 parts by weight of thermoplastic resin.
It has been found that by mixing together 0.05 to 5 parts by weight and 1 to 15 parts by weight of metal or metal sulfide, the desired plating adhesion strength can be obtained, and there is no odor during operation, and the number of days during which blooming occurs can be lengthened. The object of the present invention is to completely omit the electroless plating (chemical plating) process and to provide a thermoplastic resin composition that can be directly electroplated. 2.0Kg/cm within 5 minutes/ ^dm2
It has the above plating adhesion strength and the plating appearance is good with no pinholes or the like.
Other purposes include that the composition of the present invention has fluidity that allows injection molding, extrusion molding, etc., has no odor during work, is resistant to sulfur blooming during storage of molded products, etc., and does not bloom for more than 1 month. In addition, it has mechanical strength that can withstand practical use. The object of the present invention is to provide a resin composition for plating that satisfies all of the above objects. In addition to the composition, the present invention also includes stabilizers, lubricants, anti-aging agents,
ZnO, MgO, Mg(OH) ₂ , Al(OH) ₃ , talc,
Other fillers such as glass fiber, Sb ₂ O ₃ , ZnBO ₃ ,
Other additives such as flame retardants such as chlorinated paraffin, hexabromobenzene, and decabromophenyl oxide may also be included. This will be explained in detail in Examples below. Example 1 Polypropylene (manufactured by Sumitomo Chemical Co., Ltd., Sumitomo Noblen, W531) was used as the thermoplastic resin, VulcanXC manufactured by Kabot Corporation in the United States was used as the carbon black.
−72, nickel sulfide (NiS) as a metal sulfide,
Furthermore, sulfur was mixed as shown in Table 1. These compositions were stirred and mixed in a blender for 5 minutes, and kneaded and extruded in a twin-screw continuous extruder (65 m/m) to obtain compound pellets. This pellet
After drying at 110℃ for 3 hours, a disk with a thickness of 3 mm, 100 mmφ, and a surface area of approximately 1.6 dm ² was molded using a 5oz injection molding machine under the optimum molding conditions for each composition, and was subjected to various tests and directly electrolyzed under the following plating conditions. The properties were evaluated by plating. Plating conditions (strike nickel; Watt bath) ・Liquid composition Nickel chloride 250g / Nickel sulfate 50 〃 Boric acid 40 〃 Pitting prevention agent 2cc / ・Liquid temperature 50℃ ・Operating conditions 1V -1 minute 2V -2 minutes 3A/dm ² - After 4 minutes, put it in a copper sulfate bath or various plating baths. Characteristics include melt index (MI) for fluidity, odor for workability, number of days of blooming for storage stability, Izot impact strength and bending strength for impact resistance, peeling test for adhesion strength of plating, and appearance of plating. as pitt number,
The running time of each strike nickel was measured, and the results shown in Table 1 were obtained. As for the overall evaluation, 〇 marks are those that satisfy the present invention, and × marks are those that do not satisfy the present invention, and all the products of the present invention achieved their objectives.

[Table] Example 2 Nylon 6- manufactured by Ube Industries, Ltd. as a thermoplastic resin
1013B, polyacetal-Dyuracon M90 manufactured by Polyplastics, polypropylene-Sumitomo Noblen W-531 manufactured by Sumitomo Chemical Co., Ltd., VulcanXC-72 manufactured by Kabot Corporation of the United States as carbon black, zinc sulfide, iron sulfide, copper powder as metals. , aluminum powder, and sulfur were mixed as shown in Table 2 and examined in the same manner as in Example 1, and the results shown in Table 2 were obtained. All of the products of the present invention satisfy the objectives.

【table】

Claims (1)

[Claims] 1. A resin composition for plating, characterized in that it contains 15 to 50 parts by weight of carbon black, 0.05 to 5 parts by weight of sulfur, and 1 to 15 parts by weight of metal powder or metal sulfide to 100 parts by weight of thermoplastic resin. .