Environmental friendly chemical plating nickel plating brightener and use thereof

Abstract

The invention relates to an environment-friendly chemically nickel plating brightener. The brightener consists of 0.5 to 1.0 g / l of 1, 5-naphthalenedisulfonic acid, 0.1 to 0.15 g / l thiourea, 0.8 to 1.5g / l ferrous ammonium sulphate, 1.0 to 1.5g / l of coper sulfate, 30 to 45g / l citric acid, and the residual quantity of water. The ingredient of the brightener is free from heavy metal ions such as lead ion and chromium ion, which is harmless and environment friendly. When the brightener is applied to the chemical nickel plating solution and the to-be-plated work pieces are plated, the brightness of the plating layer can reach or be superior to the brightness effect of a brightener containing CdSO4, and the plating layer is compact, nonporous and hard. Furthermore, the brightener can function as a stabilizer, therefore, when the brightener can be applied to the chemical nickel plating solution without adding a stabilizer.

Description

【Technical field】 [0001] The invention relates to the surface treatment technology of metal materials, in particular to an environment-friendly brightener for electroless nickel plating and its application. 【Background technique】 [0002] Electroless nickel plating is a new surface treatment technology. It uses oxidation-reduction reaction to deposit a uniform, dense, smooth and smooth alloy coating on the surface of metal materials, and the coating has excellent corrosion resistance and wear resistance. Therefore, Widely used in industry. [0003] In the electroless nickel plating process, in order to ensure the stability of the plating solution and improve the brightness of the coating, stabilizers and brighteners are usually added to the plating solution. Traditional stabilizers contain lead ions, etc., while brighteners contain cadmium sulfur compounds. Since these two substances are very harmful to the environment and human health, the application of electroless nickel...

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Problems solved by technology

The amount of brightener added is very small, and its influence on the stability of the plating solution is negligible, but it has a great influence on the electrochemical performance of the plating solution.

When the brightener is added insufficiently, it will affect the quality of the coating, and if it is added too much, the coating may not be formed

However, there is one biggest difficulty in the research of brighteners for electroless nickel plating, that is, the coordination of the brightening effect and non-toxicity of brighteners.

Once widely used CdSO 4 The brightening effect of the brightener is very good, but because the Cd in the plating solution will co-deposit with the Ni-P alloy, it will cause great harm to the environment and the human body. Therefore, people hope to develop a new brightener. In the electroless nickel plating solution, the obtained coating should reach or be close to containing CdSO 4 The electroless nickel plating solution of the brightener has a bright effect, and it is non-toxic and harmless, and is friendly to the environment

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