摘要:
The slightly water-soluble metal salts having the formula I ##STR1## wherein R.sub.1 and R.sub.2 are the same or different and represent hydrogen or a lower alkyl group of from 1 to 3 carbon atoms, M is the cation of a metal which forms slightly water-soluble sulfides, and n means 1 or 2, and mixtures thereof are prepared by reacting carbon disulfide with ketones having the formula II: ##STR2## optionally with the addition of non-aqueous inert solvents, in the presence of strong alkali, preferably potassium hydroxide, followed by precipitation of the slightly water-soluble metal salts of formula I by the addition of aqueous solutions of metal salts of the metals M. They are used as gloss additives to electrolytic baths.
摘要:
A process for acidic electrolytical deposition of lead layers and predominantly lead-containing layers onto surfaces using an electrolyte containing lead salts and acids, in particular alkanesulfonic acid, borofluoric acid or silicofluoric acid, with non-ionic surfactants and cationic or amphoteric surfactants being added to the electrolyte. The process can be operated at current densities of from 0.5 to 20 A/dm.sup.2 and at a pH value below 1.