Patent · US Expired

Visible chromium- and phosphorus-free conversion coating for aluminum and its alloys

US6464800B1 · kind B1 · utility

9Cited by
10References
27Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 30, 2001
Grant dateOct 15, 2002
Priority date
Expiry dateApr 30, 2021

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC23C22/34
  • WIPO fieldSurface technology, coating
  • WIPO sectorChemistry

Abstract

A visible colored chromium- and phosphorus-free conversion coating can be formed on a metal surface by contacting it with an aqueous liquid composition that comprises an alizarine dye and a product of chemical interaction between a first initial reagent component selected from the group consisting of fluoroacids of the elements titanium, zirconium, hafnium, boron, aluminum, silicon, germanium, and tin; and a second initial reagent component selected from the group consisting of titanium, zirconium, hafnium, boron, aluminum, silicon, germanium, and tin and all of oxides, hydroxides, and carbonates of all of titanium, zirconium, hafnium, boron, aluminum, silicon, germanium, and tin.

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