Patent · US Expired

Aluminum surface with interference colors

US5904989A · kind A · utility

19Cited by
2References
23Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 3, 1997
Grant dateMay 18, 1999
Priority date
Expiry dateApr 3, 2017

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/31678
  • WIPO fieldSurface technology, coating
  • WIPO sectorChemistry

Abstract

Interference layer which acts as a coloring surface layer on aluminum items, said layer containing an aluminum oxide layer and, deposited on this, a partially transparent layer. The aluminum oxide layer is a transparent, pore-free barrier layer produced by anodizing, of predetermined thickness d corresponding to the desired surface color of the interference layer; the thickness d of the barrier layer lies between 20 and 900 nm, and the partially transparent layer exhibits a wavelength dependent transmission .tau.(.lambda.) which is greater than 0.01 and smaller than 1. The side of the partially transparent layer facing away from the barrier layer is preferably protected from mechanical and chemical effects by an additional, transparent protective layer.

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