Process for producing carbon heat generator
US4863649A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 29, 1988 |
| Grant date | Sep 5, 1989 |
| Priority date | — |
| Expiry date | Jan 29, 2008 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC04B41/009
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A process for producing a carbon heat generator is disclosed including the steps of uniformly dispersing one or more types of metal compounds capable of forming a vitreous film upon oxidation in a moldable composition, molding the resultant dispersed composition, precarbonizing the molded composition, and then carbonizing the composition in a nonoxidative atmosphere to form a carbon heat generator having an oxidation preventive glass film. The oxidation of the metal compound exposed on the surface of the molded composition by the use of an oxidative atmosphere forms a vitreous film which prevents oxygen from diffusing in the interior thereof. The film so produced can form a new glass film on a damaged portion by a self-recovery effect if a pinhole or a crack occurs in the glass film. Thus, the process does not cause external appearance and weight differences before and after heat generating.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.