Electroplating of nickel, cobalt, nickel-cobalt, nickel-iron,

Abstract

In accordance with certain of its aspects this invention relates to a process and composition for the preparation of an electrodeposit which contains; at least one metal selected from the group consisting of nickel and cobalt or; binary or ternary alloys of the metals selected from nickel, iron and cobalt; which comprises passing current from an anode to a cathode through an aqueous acidic electroplating solution containing at least one member selected from the group consisting of nickel compounds and cobalt compounds and which may additionally contain iron compounds providing nickel, cobalt and iron ions for electrodepositing nickel, cobalt, nickel-cobalt alloys, nickel-iron alloys, cobalt-iron alloys or nickel-iron-cobalt alloys and containing an effective amount of at least one additive; the improvement comprising the presence of 2.times.10.sup.-5 moles per liter to 0.1 moles per liter of an .alpha.-hydroxy sulfone having the formula: ##STR1## wherein R is selected from the group consisting of alkyl, aralkyl, aryl and alkaryl; R' is hydrogen or a mono or divalent alkyl, aralkyl, aryl, or alkaryl group, or the group ##STR2## where R is as previously defined; and n is an integer 1 or 2 corresponding to the valence of R'; additionally when n is 2, R' may be absent; for a time period sufficient to form a metal electroplate upon said cathode.