Low-concentration weakly alkaline cyanide-free copper plating and bath solution preparing method

Abstract

The invention relates to a bath solution preparing method and a low-concentration weakly alkaline cyanide-free copper plating which can ensure that the bonding force exists between a plating layer and a matrix, the plating solution has best stability, better dispersing capacity and deep plating capacity and simple process maintenance. The low-concentration weakly alkaline cyanide-free copper plating comprises a main salt, a conductive salt, a main complexing agent and a secondary complexing agent, wherein the main salt is copper chloride, the conductive salt comprises a mixture of sodium chloride, potassium chloride and ammonium chloride, the main complexing agent is a mixture of tartrate, citrate, nitrilotris(methylene)]tris-phosphonic acid salt, (1-Hydroxyethylidene)bis-phosphonic acid tetrasodium salt and ethylenediamine tetra(methylenephosphonic acid) salt; and the secondary complexing agent is a mixture of ortho-hydroxybenzoic acid, succinimide and derivatives thereof and dimethyl hydantoin. The invention has the advantages of capability of ensuring the bonding force of the plating and the matrix, best stability and better dispersing capacity and deep plating capacity and simple process maintenance.

Description

technical field [0001] The invention relates to a low-concentration weakly alkaline cyanide-free copper plating and bath which can not only ensure the bonding force between the plating layer and the substrate, but also have excellent stability of the plating solution, good dispersion ability and deep plating ability, and simple process maintenance. The liquid preparation method is mainly used in the metal electroplating pre-plating process of sanitary ware, hardware, auto parts, motorcycle parts and other industries. It has good bonding force and fine crystallization, and belongs to the field of cyanide-free copper plating and bath liquid preparation methods. Background technique [0002] 85103672, titled "Ethylene Glycol Copper Plating", this invention proposes a new cyanide-free electroplating copper bath solution, in which steel-based workpieces can directly obtain an electrodeposited copper layer with good bonding force. The bath is composed of a compound containing Cu(I...

AI Technical Summary

Problems solved by technology

[0006] Although there are different defects in the above-mentioned background technology, the main performance is that the bonding force between the copper plating layer and the substrate does not meet the requirements, the pre-treatment requirements are also high, the first-time pass rate of the product is low, and the process maintenance is relatively difficult.

[0007] Copper plating in pyrophosphate system: it has a wide range of applications and has defects, such as direct copper plating on steel substrates, due to [Cu(P 2 o 7 ) 2 ] 6- The complexation of Changshu is only 1.0*10 -9 , can not completely overcome the influence of the displacement reaction to reduce the binding force

And with the extension of electroplating time, pyrophosphate is gradually converted into orthophosphate, the viscosity of the plating solution is increasing, the current efficiency is reduced, and wastewater treatment is difficult, etc.