GB841529A - A process for the production of electrolytic metal coatings - Google Patents

Abstract

841,529. Electrode position of bright nickel and cadmium. DEHYDAG, DEUTSCHE, HYDRIERWERKE G. m.b. H. Oct. 4, 1956 [Oct. 7 1955], No. 30220/56. Class 41. Bright adherent nickel or cadmium electrodeposits are produced from baths containing in addition to a salt of nickel or cadmium an organic disulphimide containing one or more of the halogen atoms chlorine or bromine, or a water-soluble salt thereof, in the absence of compounds comprising two heterocyclic radicals each containing a nitrogen atom in the ring and in the absence of coumarin or its derivatives. Suitable halogenated disulphimides are the 4-chloro, 4-bromo, 44<SP>1</SP>-dichloro, 4:41-dibromo, 4-chloro-41-bromo, 3-4:31:41-tetrachloro, 3- chloro-4:4<SP>1</SP>-dimethyl, 3:3<SP>1</SP>-dichloro-4:4<SP>1</SP> dimethyl and 4-(C 1 -C 8 ) alkyl-41-chloro or-bromo derivatives of dibenzene disulphimide and 4- chloro or-bromo-benzene-(C 1 -C 8 ) allkane disulphimides, or their alkali metal or ammonium salt, used in concentrations of 0À1 to 10 gms/litre. Examples are given of such compounds added to Watts nickel baths. Levelling agents such as (a) the internal salts formed by reacting tertiary mono-or poly-nuclear heterocyclic aromatic nitrogen bases with sultones referred to in Specification 815,916, e.g. quinolinium - or pyridinum- N-propanesulphonic acid, (b) bis-or poly-thioureas, -isothioureas, and -thiocarbamates as used in Specification 828,200 and (c) internal salts of isothiourea-alkane-sulphuric acids as used in Specification 762,257 may also be added to the bath in concentrations between 0À1 and 1 gm/litre as well as brighteners such as the organic disulphimides used in Specification 721,204, porepreventers such as sodium alkyl sulphates in a concentration of 0À2 to 3 gms/litre, and conducting salts e.g. inorganic alkali metal salts. Reference has been directed by the Comptroller to Specification 525,847.