Abstract: A brighter, more uniform deposit of electroless silver is achieved over a wider temperature range by employing as a reducer a compound represented by the general formula:R.sup.2 --(CHR.sup.1).sub.n --CH.sub.2 OHwhere n is two (2) to seven (7), R.sup.2 is represented by the formula COOH or CH.sub.2 R.sup.1, each R.sup.1 group is independently selected from the class consisting of OH, NH.sub.2, NHCH.sub.3, NHC.sub.2 H.sub.5 or NHC.sub.3 H.sub.7 and at least one of the R.sup.1 groups is NH.sub.2, NHCH.sub.3, NHC.sub.2 H.sub.5 or NHC.sub.3 H.sub.7.Preferred reducers are N-methylglucamine, d-glucamine and glucosaminic acid.

Abstract: Potentially explosive mixtures which can form as a result of accidental contact between a concentrated aqueous solution of ammoniacal silver salt and a concentrated solution of a strong alkali are inhibited in an improved multi-part system for electroless deposition of silver on an activated surface by simultaneous admixture of the diluted parts thereupon. Accordingly, an improved method for inhibiting formation of explosive conditions and compounds in a mixture formed by contacting concentrated aqueous ammoniacal silver salt and a concentrated solution of alkali is provided, whereby an effective amount of an explosion inhibitor is provided either in combination with the ammoniacal silver salt, in which case sufficient extraneous ammonium ions are provided to stabilize the explosion inhibitor, or in the strong alkali, or a portion of the explosion inhibitor is provided in each of said ammoniacal silver salt and strong alkali.

Abstract: Apparatus for removal of soluble metal ions, preferably copper ions, from an effluent solution is provided comprising a chamber for continuous passage of effluent therethrough having high surface area donor and acceptor electrodes in physical contact provided therein. One preferred embodiment comprises a rectangular tank having a multiplicity of high surface area stainless steel and aluminum electrode members comprising screens or expanded or perforated sheets bisecting the flow of effluent therethrough and being in physical contact. An alternate embodiment comprises a cylindrical tank having a "jelly-roll" configuration of stainless steel and alumium screens in physical contact provided in the center of the tank, along its longitudinal axis. A method for removal of soluble metal ions from effluent solution is provided comprising treatment of the effluent by passage through the apparatus of the invention.

Abstract: This invention relates to processes and compositions for the deposition of metallic copper on a catalytically activated surface by the controlled disproportionation of cuprous ions. Cupric tetraammino ions in aqueous solution are rapidly reduced to cuprous diammino ions and the latter are acted upon by the addition of an activator-modifier so as to bring about controlled disproportionation resulting in the deposition of metallic copper principally on the catalytically activated surface of a workpiece.