Method for electrodepositing ornamental chromium coating in trivalency chromium coating solution

Abstract

The invention discloses a method to produce the decorated chrome plating layer in trivalence chrome electroplate liquid. The invention is to select the proper additive and control the condition in the base electrolyte containing the chromium chloride to produce the non-crystal chrome plate with smooth surface and no crack, also which is the light and anti-corrosion as same as the sexivalent chrome plating. The process is stable, the operation condition is wide and the energy cost is low; also the ability of disperse, covering and current flow effect are high than sexivalent chrome plating process. The thickness of plating chrome is 0.5-1 mu m. So the invention can instead of the sexivalent process and be used in all anticorrosion and decorated field.

Description

technical field [0001] The invention relates to an electrodeposition method for preparing a decorative chromium coating in an environment-friendly trivalent chromium plating solution. Background technique [0002] Decorative chrome coating has become one of the most widely used decorative coatings in the industry due to its good gloss and corrosion resistance. However, for a long time, the traditional hexavalent chromium electroplating process has many insurmountable shortcomings, such as poor dispersion and coverage, low current efficiency, high electroplating temperature, serious pollution to people and the environment during the electroplating process, and difficult post-treatment of the plating solution. During the hexavalent chromium electrodeposition process, waste water and waste gas contain a large amount of hexavalent chromium, which causes great pollution to the environment, and can cause human kidney failure, heart failure, leukemia, and can strongly cause cancer....

AI Technical Summary

Problems solved by technology

Vapor deposition technology has the advantages of low pollution and uniform deposition, but its high cost and poor coverage ability cannot be used for the deposition of irregular workpieces and inner walls of pipe fittings, and it is not conducive to large-scale industrial production

Electrodeposited alloy instead of chromium coating mainly includes Zn-Sn-Co, Ni-P, Ni-W and other ternary alloys. This method has little pollution, but the stability of the plating solution is poor and the operating conditions are narrow.

In contrast, the toxicity of the decorative trivalent chromium electrodeposition process is only 1% of that of the hexavalent chromium electroplating process, with low energy consumption and high efficiency, but its disadvantages are poor gloss of the coating and poor stability of the plating solution

Although the industrial promotion of decorative trivalent chromium electroplating process has been reported abroad, there is no report on domestic decorative trivalent chromium electroplating process that has independent intellectual property rights and can be applied to industrial production.