Plastics materials having electrodeposited metal coatings

Abstract

Abstract It is known to coat plastics materials, especially thermoplastics such as ABS, with metal by electrodeposition, typically with chromium on top of nickel. Conventional methods are often unsatisfactory when applied to thermosetting resinbased articles, the metal coating peeling or flaking off when the articles are subjected to repeated changes in temperature. It has now been found that copper or nickel coatings adhere well to surfaces, prepared in a conventional manner, of thermosetting plastics as well as of thermoplasts, provided that the coatings are electrodeposited in a manner such that they have an average stress in tension of at least 2,000 kg./sq. cm. E.g., a molding prepared from ''''Araldite'''' MY 750, HT 972, calcined china clay and glass fibers, is prepared for electroplating by A. ETCHING WITH CHROMIC ACID B. DEPOSITING A FILM OF PALLADIUM THROUGH TREATMENT WITH STANNOUS CHLORIDE AND PALLADIUM CHLORIDE SOLUTIONS C. DEPOSITING A FILM OF COPPER OR NICKEL BY REDUCTION OF COPPER SULPHATE OR NICKEL SULPHATE SOLUTIONS. Next, a nickel coating is electrodeposited under conditions such that it had an average stress in tension of 2,440 to 6,460 kg./sq. cm.: this coating being dull, a bright, lightly stressed nickel coating was electrodeposited before the final layer, of chromium, was applied.

Inventors

• 👤 Peter Thomas Brown
• 👤 John Rowland

Bibliographic Details