Durable substrates having porous antireflection coatings
US4080188A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 22, 1976 |
| Grant date | Mar 21, 1978 |
| Priority date | — |
| Expiry date | Nov 22, 1996 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B1/113
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A porous layer is formed on a surface of a body of phase separable glass by heat treating the glass to cause it to become separated into at least two distinct phases of different solubility. A surface of the body is subjected to a leaching solution which preferentially leaches at least the most soluble phase, leaving a surface layer consisting of a skeletal structure that comprises the least soluble phase disposed on a substrate of phase separated glass. The glass body is then subjected to a second heat treatment at a sufficiently high temperature that the phase separated glass substrate is caused to become homogeneous, the porous surface layer remaining substantially unchanged. The resultant homogeneous glass substrate is more chemically durable than it was in the phase separated state.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.