Patent ID: 8828278

Claim:
A process for coating a substrate with a binary or ternary group IB-group IIIA/ternary, quaternary or pentanary group IB-group IIIA-group VIA alloy comprising the following steps: (i) pre-cleaning the substrate to be coated and (ii) contacting the pre-cleaned substrate with a metal plating composition comprising an additive of the general formula (A) in a concentration range from 1 to 500 ppm: wherein X 1 and X 2 may be the same or different and are selected from the group consisting of arylene and heteroarylene; FG 1 and FG 2 may be the same or different and are selected from the group consisting of —S(O) 2 OH, —S(O)OH, —COOH, —P(O) 2 OH and primary, secondary and tertiary amino groups and salts and esters thereof; R is selected from the group consisting of alkylene, arylene or heteroarylene and n and m are integers from 1 to 5; and further comprising a group IB plating species and a group IIIA plating species, and a buffer system in an amount such that the composition has a pH value from about 1 to about 6, at a temperature from about 15° C. to about 80° C. to obtain a substrate coated with a binary or ternary group IB-group IIIA/ternary, quaternary or pentanary group IB-group IIIA-group VIA alloy.