Process for producing spherical glass particles
US4961770A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 6, 1989 |
| Grant date | Oct 9, 1990 |
| Priority date | — |
| Expiry date | Mar 6, 2009 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC03B19/1025
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A composition is disclosed consisting essentially of substantially spherical glass particles having a diameter of less than about 25 micrometers. A process is disclosed for producing substantially spherical particles. The process involves providing irregularly shaped glass particles having a predetermined particle size, entraining the particles in a carrier gas, feeding the entrained particles into a high temperature zone having a temperature sufficiently above the softening point of the glass to allow surface tension to subsequently spheroidize the particles and having a temperature below the vaporization temperature of the glass. The particles are maintained in the high temperature zone for a sufficient time to convert at least a portion of the particles into droplets without the formation of a substantial amount of filaments affter which the droplets are cooled to form solid spheres having essentially the same particle size as the irregularly shaped particles and a reduced surface area as compared with the irregularly shaped particles.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.