DAIWA FINE CHEMICALS CO., LTD.
|DAIWA FINE CHEMICALS CO., LTD. Patent applications|
|Patent application number||Title||Published|
|20090321269||SILVER AND SILVER ALLOY PLATING BATH - To develop stable, non-cyanide silver and silver alloy plating baths. The present invention is a silver and silver alloy plating bath, comprises: (A) a soluble salt, comprising a silver salt or a mixture of a silver salt and a salt of a metal selected from the group consisting of tin, bismuth, cobalt, antimony, iridium, indium, lead, copper, iron, zinc, nickel, palladium, platinum, and gold; and (B) at least one aliphatic sulfide compound comprising a functionality selected from the group consisting of an ether oxygen atom, a 3-hydroxypropyl group, and a hydroxypropylene group, with the proviso that the aliphatic sulfide compound does not comprise a basic nitrogen atom.||12-31-2009|
|20090159453||METHOD FOR SILVER PLATING - The aim of the present invention is to provide a method for silver plating that does not comprise the step of forming the nickel-underlayer and that can form a silver-plated layer having sufficient adherence directly on the difficult-to-plate substrates with the use of a halide-free plating bath under a good working environment. The present invention provides a silver plating method onto a substrate on which an oxide layer inhibiting adherence of a plated layer is prone to form, comprising at least the following steps of; (A) degreasing the substrate, (B) removing the oxide layer with a strongly acidic solution from the substrate, and (C) silver plating onto the substrate, without a step of nickel or nickel alloy strike plating in advance, utilizing a phosphines-containing acidic silver plating bath which essentially does not contain halide ion or cyanide ion.||06-25-2009|