JPS5933676B2 - Resin composition for coating plating jigs - Google Patents

Description

[Detailed description of the invention] The present invention relates to a resin composition for coating a plating jig.

Plating of non-conductive materials such as plastics and ceramics generally involves degreasing the substrate to be plated made of these materials, roughening the surface with corrosive chemicals such as acids, applying a plating catalyst to the surface, and electroless plating. , electroplating.

When these treatments are carried out, the substrate to be plated is hung on a jig called a rack and passed through each process, but in the final electroplating process, the rack also serves as a conductor, so it must be a conductor. Since the surface must not be plated at the same time, a metal material whose surface is coated with a paint such as vinyl chloride resin or polyethylene is used as a rack for carrying electricity.

However, while degreasing the surface of the plated substrate made of non-conductive materials such as plastic, chemically roughening the surface, and activating the surface by adding a catalyst, the surface of the coating resin on the rack also becomes activated. During the electroless plating process, plating also deposits on the resin coating surface of the rack. For this reason, racks that are designed to be current-carrying bodies that can be used in electroplating processes cannot be used as they are in electroplating processes, and the substrate to be plated must be replaced with another rack, or the precipitate plating on the rack surface must be changed. Peeling work is required, which is a major obstacle to streamlining the plating process. Various methods have been proposed to avoid this, for example, ABS
In resin plating, a common method is to use a strong oxidizing chemical to roughen the surface, thereby changing the quality of the rack-coated resin surface.

However, it goes without saying that this method cannot be applied to substrates to be plated where such chemicals cannot be used. Furthermore, Japanese Patent Publication No. 52-5006 discloses that by incorporating an aromatic or heterocyclic mercapto compound or an aromatic or heterocyclic sulfide compound into a coating resin composition, electroless plating on the surface of the coating resin is possible. It is disclosed that precipitation can be prevented.

This is thought to be because the sulfur compound acts as a catalyst poison for the reduction catalyst in electroless plating. However, the coating resins containing sulfur compounds that have been proposed so far have the following drawbacks and are not practical. (1) The added sulfur compound blooms on the coating resin surface more than necessary, and if it is used in the plating process as it is, the bloomed sulfur compound will desorb and contaminate the liquid in the subsequent process, or it will elute into the catalyst liquid. to deactivate the catalyst.

(2) Some of the proposed sulfur compounds emit a foul odor, and therefore the environment may be seriously polluted when the compounds are mixed, during the coating operation of the composition, or during subsequent baking. , special equipment will be required to remove the odor. Therefore, the inventors of the present invention have carried out various studies in order to develop a coating resin composition that does not cause plating to deposit on the coating resin surface and at the same time does not have the above-mentioned drawbacks.As a result, surprisingly, the sulfur compound of the present invention It has been found that only the composition in which a predetermined amount is added satisfies these requirements at the same time.

That is, in the present invention, the following formula (1) is added to 100 parts by weight of the coating resin.
A compound represented by (where Rl, R2, R3, and R4 are straight-chain or branched alkyl groups having 1 to 12 carbon atoms, and may be different or the same).

Moreover, x represents 1 or 2. ) is added thereto in an amount of 1 to 10 parts by weight. Examples of the compound represented by formula (1) in the present invention include tetramethylthiuram monosulfide, tetramethylthiuram disulfide, tetraethylthiuram disulfide, tetra-n-butylthiuram disulfide, and tetraisooctylthiuram. Examples include disulfide, dimethyldiethylthiuram disulfide, and the like.

The amount of the sulfur compound of the present invention added is 1 to 10 parts by weight, preferably 2 to 6 parts by weight, per 100 parts by weight of the coating resin.
Parts by weight.

If the amount added is less than 1 part by weight, plating will be deposited on the surface of the coating resin, and if the amount added exceeds 10 parts by weight, it will affect the solidification of the coating resin or increase the cost, which is preferable. The number X of sulfur in the sulfur compound of the present invention is preferably 1 or 2.

If the number of sulfur is 3 or more, the sulfur compound will bloom on the surface of the coating resin, which is not preferable. Coating resins that can be used in the present invention include commercially available vinyl chloride resins,
Polyethylene resin or the like may be used.

When coating a plating jig with the coating resin composition of the present invention, it may be applied once or twice to a metal material such as copper or stainless steel and baked.

As described above, for the first time when using the resin composition of the present invention, plating does not precipitate on the coated area, and at the same time, even when repeatedly and continuously used in each process of electroless plating, the sulfur compound in the resin composition is It does not elute, therefore, it does not contaminate the liquid in each process or deactivate the catalyst liquid, and furthermore, there is no bad odor when applying or baking the resin composition on a jig, and a special resin composition for this purpose is used. It has been found that this method has the advantage that no special equipment is required, and it has made it possible industrially to simplify plating jigs for electroless plating of plastics, ceramics, etc.

Next, examples of the present invention will be shown.

Example 1 5 parts by weight of tetra-n-butylthiuram disulfide was added to 100 parts by weight of a vinyl chloride resin liquid (Eposol SH-106, manufactured by Eposol Co., Ltd.), and the mixture was stirred and mixed while degassing until the mixture became uniform.

This resin composition was applied to a copper alloy jig, heated at 175°C,
The 3 minute baking operation was repeated twice. At this time, I could not detect any bad odor. An acetal resin molded article was hung on this jig, degreased, etched with an etching solution consisting of sulfuric acid/phosphoric acid, catalyzed and activated, and chemically nickel plated. No plating was deposited on the tool, and only the molded product was nickel-plated.
Subsequently, when this product was electroplated in the order of copper, nickel, and chromium, the jig was not plated, and only the target polyacetal resin molded product was plated. Although this jig was repeatedly used in the electroless plating process 100 times, no plating was deposited on the coating resin surface of the jig, and there were abnormalities such as blooming of sulfur compounds on the coating resin surface and deactivation of catalyst liquid. No phenomenon was observed. Example 2 Polyethylene resin (Frocene G-801 manufactured by Steel Chemical Co., Ltd.)
) 2.5 parts by weight of tetraethylthiuram disulfide was added to 100 parts by weight and mixed with stirring, which was applied to a copper alloy jig and baked at 175° C. for 3 minutes twice.

At this time, no foul odor was detected. A polyacetal resin molded product was hung on this jig, and electroless plating and electroplating were repeated 100 times in the same manner as in Example 12.
No plating was deposited on the surface of the jig, and no abnormal phenomena such as blooming on the surface or deactivation of the catalyst liquid were observed.

Example 3 4 parts by weight of tetramethylthiuram monosulfide was added to 100 parts by weight of a vinyl chloride resin liquid (Eposol SH-106, Epozol Co., Ltd.), and the mixture was stirred and mixed and applied to a copper alloy jig. Baked at ℃ for 3 minutes.

This coating and baking operation was repeated twice. At this time, I could not detect any bad odor. A polyacetal resin molded product was hung on this jig, and electroless plating was performed in the same manner as in Example 1.
Although electroplating was repeated 100 times, no plating was deposited on this jig, and no abnormal phenomena such as blooming on the jig surface or deactivation of the catalyst liquid were observed. Comparative Example 1 1.0 parts by weight of pentachlorobenzenethiol was mixed with 100 parts by weight of vinyl chloride resin liquid (Eposol SH-106, Epozol Co., Ltd.), and the mixture was applied to a copper alloy jig and heated at 175°C for 3 minutes. The baking process was repeated twice.

At this time, I could smell a very bad odor. A polyacetal resin molded article was placed on the coated jig and plated in the same manner as in Example 1. After repeated use of the jig three times, plating was deposited on the surface of the jig.

In addition, an abnormal phenomenon was observed in which pentachlorobenzenethiol bloomed on the surface of the coated resin and the catalyst liquid was partially deactivated. Comparative Example 2 100 parts by weight of vinyl chloride resin liquid (Eposol SH-106, Eposol Co., Ltd.) was mixed with 1 part of 2-thiobaldecturic acid.
After mixing parts by weight, apply it on a copper alloy jig to obtain 175
Baking for 3 minutes at ℃ was repeated twice.

In this case, a bad odor was felt when the resin liquid was mixed, applied, and baked. When an acetal resin molded article was hung in this jig and subjected to the same plating treatment as in Example 1, plating was deposited on the surface due to only one plating treatment.

Claims (1)

[Claims] 1. 100 parts by weight of coating resin contains a compound represented by the following formula (I) ▲ Numerical formula, chemical formula, table, etc. ▼ (I) (
Here, R_1, R_2, R_3, R_4 have 1 to 1 carbon atoms.
The two straight-chain or branched alkyl groups may be different or the same. Moreover, x represents 1 or 2. ) is added in an amount of 1 to 10 parts by weight, a resin composition for coating a plating jig.