Patent · US Expired

Additives for lead-free frits

US5149565A · kind A · utility

4Cited by
0References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 31, 1991
Grant dateSep 22, 1992
Priority date
Expiry dateOct 31, 2011

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC03C8/16
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

This invention is drawn to a method for eliminating the grayish discoloration which customarily develops when lead-free and cadmium-free glass frits are applied to substrates employing an organic vehicle and which are thereafter fired to fuse the frit particles into a glaze. The grayish hue results from a carbonaceous residue left upon thermally decomposing the organic vehicle. The inventive method comprises five general elements: PA0 (a) glass frit particles of a desired composition are prepared; PA0 (b) a coating of an organic compound containing at least one sulfur oxide group as an oxidizing agent is adsorbed on the surface of the particles; PA0 (c) the coated particles are mixed with an organic vehicle; PA0 (d) that mixture is coated onto a surface of a substrate; and PA0 (e) that coated substrate is fired to fuse the frit particles into a glaze, the oxidizing agent eliminating the carbonaceous residue left upon thermal decomposition of the organic vehicle.

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