Silica-rich porous substrates with reduced tendencies for breaking or cracking
US4933307A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 21, 1988 |
| Grant date | Jun 12, 1990 |
| Priority date | — |
| Expiry date | Apr 21, 2008 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC03C11/00
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Porous, silica-rich shapes have improved strength and abrasion resistance by leaching the precursor glass shape in preconditioned acid having silica ion and at least one common ion that is also present in the precursor glass shape. The precursor glass shapes have shapes such as fibers, hollow fibers, tubes, rods, beads, hollow spheres and plates and compositions having 30-75 volume percent silica and at least 10-65 volume percent nonsiliceous acid extractable components. Preconditioning of the acid solution results from a pretreatment of the acid with compounds that dissociate into the ions when added to the acid solution or with shapes, particles or fragments of glass compositions different from or similar to the glass shape to be leached so long as the glass composition has extractable material to provide the silica ion and at least one common ion.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.