derivatives of benzaldehyde which contain an electron donating group on the benzene ring some of the carboxylic acids which are useable in the electroplating solution of the invention include methacrylic acid acrylic acid and their derivatives in one embodiment the aromatic aldehyde comprises chlorobenzaldehyde and the carboxylic acid comprises methacrylic acid to improve the dispersibility of the solution and suppress the growth of dendrites a non ionic surfactant and a grain refiner are added to the solution the non ionic surfactant improves the dispersibility of the solution and also ensures that the plated solder coatings adhere well to the underlying substrate the grain refiner suppresses the growth of dendrites examples of suitable non ionic surfactants include aromatic compounds such as substituted and unsubstituted phenyl and phenol compounds examples of suitable grain refiners include heterocyclic compounds such as substituted and unsubstituted lactones cyclic imides and oxazolines in one embodiment the non ionic surfactant comprises a polyalkoxylated alkyl phenol such as octylphenoxy 10 polyethoxy ethanol and the grain refiner comprises phenolphthalein to prevent evaporative loss of the brighteners diols are added to the bath the diols remain in the solution and they also keep the volatile brighteners in the solution the aldehyde phase does not separate and does not evaporate as.