Patent · US Expired

Chromate treatment of a metal coated steel sheet

US4784731A · kind A · utility

5Cited by
2References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 12, 1987
Grant dateNov 15, 1988
Priority date
Expiry dateMay 12, 2007

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC25D11/38
  • WIPO fieldSurface technology, coating
  • WIPO sectorChemistry

Abstract

A chromate treatment of metal coated steel sheets comprising subjecting the sheets to a cathodic electrolytic treatment to form a chromate film thereon and subjecting the sheet to an anodic electrolytic treatment to form an anodic electrolytic film on the chromate film and to convert the chromate film. The treatment is applicable to various metal coated steel sheets, such as those coated with zinc, zinc alloy, aluminum, aluminum alloy, lead and lead alloy, and is effective to improve the corrosion resistance of the sheets, the quality of paint coating applied on the sheets and the adaptability of the sheets to a cation electro-deposition paint coating.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.