TRIPYRIDINIUM COMPOUNDS USED AS ADDITIVES IN AQUEOUS ALKALINE BATHS, DEVOID OF CYANIDE, FOR THE DEPOSITION OF ELECTROPLATED ZINC AND ZINC ALLOY COATINGS

摘要

The invention relates to an aqueous alkaline electrolyte bath, devoid of cyanide, for depositing zinc and zinc alloy layers on substrate surfaces. Said bath comprises the following components: (a) a zinc ion source and optionally a source for additional metal ions; (b) hydroxide ions; and (c) at least one tripyridinium compound of general formula (I). The electrolyte bath is suitable for the deposition of glossy, uniform electroplated zinc and zinc alloy coatings. The invention also relates to the use of compounds of formula (I) as brighteners.