Method to increase the strength of a form body of a lithium silicate glass ceramic
US11040909B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 20, 2016 |
| Grant date | Jun 22, 2021 |
| Priority date | — |
| Expiry date | Apr 7, 2037 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC03C2204/00
- WIPO fieldPharmaceuticals
- WIPO sectorChemistry
Abstract
The invention relates to a method to increase the strength of a form body of lithium silicate glass ceramic, which after it has a desired end geometry and after the application of a material which influences its surface to form a coating, is subject to a heat treatment. To create a surface compressive stress through the replacement of lithium ions by alkali ions of greater diameter at least that region not covered by the application layer is covered by a melt or paste consisting of or containing a salt of an alkali metal with ions of greater diameter and the form body is in contact with the melt or paste for a period of time t at a temperature T and the melt or paste is subsequently removed from the form body.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.