BRIGHT NICKEL ELECTROPLATING BATH CONTAINING SULFO-OXYGEN CONTROL AGENT, NITROGEN-CONTAINING BRIGHTENER AND MINOR CONCENTRATION OF TERMINAL ACETYLENIC ALCOHOL OR DERIVATIVE

摘要

1,224,179. Bright nickel electro-deposition. KEWANEE OIL CO. Feb.22, 1968 [Feb.28, 1967], No.8710/68. Heading C7B. Bright nickel is electro-deposited from an aqueous nickel salt solution containing also (a) a a sulpho-oxygen control agent which is a mono-or poly-nuclear aromatic sulphonic acid or salt or sulphonamide or sulphonimide, an aliphatic sulphonic acid or salt, or a heterocyclic sulphonic acid; (b)a nitrogen-containing brightener which is an aromatic mono- or poly-amine, a polyethylene polyamine, a nitrile, or pyridine or a homologue or derivative thereof having only one nuclear nitrogen atom: this brightener having an addition to nitrogen only hydrocarbon, halogen, ether thioether, hydroxy, carboxy or carboxylate groups or in the case of pyridine compounds also alkyl sulphonic or sulphonate groups; and (c) an acetylenic compound CH=C-R where R is a hydroxy-substituted C 1 to C 8 alkyl alkenyl or cycloalkyl group or an alkyleneoxy derivative thereof containing no more than four C 1 to C 4 alkyleneoxy groups the acetylenic alcohol being present in an amount of from 0.003 to 0À1 g/1 and the nitrogen-containing brightener being present in an amount of from 0.005 to 1 g/1. The use of the nitrogen-containing brightener in combination with the "over-effective" acetylenic brighteners permits obtaining at least "bright semi-bright" deposits in low current density areas without striation or other undesirable effects in high current density areas. Examples of specified Nitrogen-containing brighteners are p-p'-diaminodiphenyl ether, tetraethylenepentamine, ethylene cyanohydrin, thiodipropionitrile, 1-carboxymethyl pyridinum chloride, pyridinum- N-propane-w-sulphonic acid, N-allyl quinaldinium bromide. As described the nickel bath is of the Watts type. The harmful effects on brightness of metallic impurities such as copper or zinc are overcome by the brightener combination of the invention.