Volatilizable frit composition forming oxidation-inhibiting vapors
US4084975A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Aug 2, 1976 |
| Grant date | Apr 18, 1978 |
| Priority date | — |
| Expiry date | Aug 2, 1996 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC03C2207/00
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A frit composition is disclosed adapted to be applied to a metal substrate containing iron and fired to form a ceramic coat. The frit composition comprises a primary devitrifiable frit adapted to fuse at a firing temperature and upon cooling form devitrified particles; and a secondary frit containing a volatilizable metal oxide adapted to form at a firing temperature substantially an amorphous glass and precipitate crystals of the volatilizable metal oxide. The crystals at least partially volatilize at the firing temperature to provide protective vapors effective to inhibit oxidation of the substrate. Upon cooling, the amorphous glass of the secondary frit bonds the devitrified particles of the primary frit one to another. Preferably, the devitrified particles of the primary frit provide a porous ceramic coat such as on a surface of a self-cleaning cooking device exposed to cooking residues. In this case, the primary frit may also contain an oxidation catalyst.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.