GB745665A - Process for plating objects with conducting surface with a highly brillant nickel coating - Google Patents

Abstract

745,665. Electrodeposition of nickel. NAAMLOOZE VENNOOTSCHAP METALLIC INDUSTRY. March 18, 1953, No. 7549/53. Class 41. A process for electroplating conducting surfaces with bright nickel comprises using a nickel bath containing at least one sulphonated unsaturated compound or salt, amide, imide or halogen derivative thereof, or sulphonated aromatic compound, and at least one bi- or polynuclear compound possessing one or more sixmembered rings which may be condensed, and optionally also possessing five-membered rings, such compound comprising a six-membered ring joined by one or more carbon-to-carbon links to a five- or six-membered ring, at least one of the five- or six-membered rings containing basic nitrogen, at least one of said five- or six-membered rings being substituted by a hydroxyl, substituted hydroxyl, nitro or nitroso group. The sulphonated compound may be vinyl sulphonic acid, 1-chloro vinyl sulphonic acid, 1-bromo vinyl sulphonic acid, allyl sulphonic acid and its halogen derivatives, benzene, toluene or naphthalene sulphonic acids, obenzoyl sulphonimide, p-toluene sulphonamide, or saccharin. The sulphonated compound may be used in concentrations of from 0.5 grams per litre to saturation. The bi- or poly-nuclear compound, which may be used in concentrations of 5 to 25 milligrams per litre, preferably has one or more carboxylic acid groups and/or carboxylic acid amide groups. Examples of bi- or poly-nuclear compounds are 3-nitroso-2- phenyl indole, 2-(p-nitrophenyl)-pyridine, 2-(ohydroxyphenyl)-pyridine, and 2-phenyl-6-(pmethoxyphenol)-pyridine. The nickel bath may contain nickel sulphate and chloride, boric acid and sodium lauryl sulphate. Specification 525,847 is referred to.