Electrolytic plating of tin-nickel, tin-cobalt or tin-nickel-cobalt on a metal base and acid bath for said plating

Claim 2

A method as claimed in claim 1, wherein said fluoride or fluoroborate salt is formed from an amine selected from the class consisting of ethylenediamine, diethylenetriamine, triethylenetetramine, monoethanolamine, diethanolamine, triethanolamine, N-benzyldiethanolamine, N''-benzyl-N, N-dimethylethylenediamine, N, N-diethylcyclohexylamine, dicyclohexylamine, and tetraethylenepentamine.

Claim 3

A method as claimed in claim 1, wherein said bivalent tin, nickel, cobalt salt are in the bath in the form of their sulfate, sulfonate, chloride, acetate, citrate, or lactate salts.

Claim 4

A method as claimed in claim 1 wherein said pH is 4.8.

Claim 5

An aqueous acid bath at pH 3.8 to about 5.5 containing bivalent water soluble salts of nickel, tin and cobalt in amounts for nickel and cobalt equivalent to 125 to 450 grams per liter as bivalent nickel chloride and 25 to 110 grams per liter as stannous chloride there being also present in said bath the combination of 20 to 100 grams per liter (1) alkali or ammonium fluoride or (2) alkali or ammonium fluoroborate with a non-volatile amine derivative reactive with said fluoride or fluoroborate to form the amine salt thereof, the amine of said amine salt being present in an amount of from 40 to 100 cubic centimeters per liter, said bath adapted for the electrolytic deposition of corrosion resistant tin-nickel, tin-cobalt and tin-nickel-cobalt coatings on a metal base providing by passing current through said bath at an average current intensity between 0.1 to 5 amperes per square decimeter using a nickel anode and providing said metal base as the cathode.