PROCEDEU POUR ARRETER LA VOLATILISATION DE L'OXYDE DE CHROME(VI)DE BAINS ELECTROLYTIQUES DE CHROMAGE

摘要

The essence of the invention is that a product of the ethoxylation of the alkylamines or alkylarylamines or alkanolamides of higher fatty acids is added to the chromium-plating solution, the active concentration of the surfactants in the chromium-plating bath being between 10<-14> and 0.1% by mass. The abovementioned product of the ethoxylation of the alkylamines or alkylarylamines contains an alkyl group having from 8 to 20 carbon atoms and 5 to 25 mol of bound ethylene oxide, the aryl group being represented by phenyl, in particular by alkylaminopolyethylene glycol ether having 18 carbon atoms in the aryl group and 7 mol and/or 20 mol of bound ethylene oxide and/or by a mixture thereof. The product of the ethoxylation of the alkanolamides of the higher fatty acid contains 5 to 25 mol of bound ethylene oxide. The alkyl chain of the fatty acid contains up to 17 carbon atoms and from 2 to 3 carbon atoms in the alkyl bound to the amino group. This may be, in particular, the ethoxylated diethanolamide of stearic acid containing 6 mol of grafted-on ethylene oxide. The invention can be used in all those areas in which chromium electroplating is carried out.