Method of coating electrostatographic carrier particles
US3940514A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 17, 1973 |
| Grant date | Feb 24, 1976 |
| Priority date | — |
| Expiry date | Dec 17, 1993 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03G9/1131
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A method of coating electrostatographic carrier particles comprising introducing an upwardly flowing low pressure gas and a centrally located upwardly flowing high pressure gas at about one-third their full flow rate into a combined fluidized bed and spouted bed coating apparatus, loading carrier particles into the coating apparatus, increasing the flow rate of the low pressure gas to its full flow rate of about 305 cubic feet per minute with heating to heat the carrier particles, increasing the flow rate of the high pressure gas to its full flow rate of about 16 cubic feet per minute at about 1.5 atmospheres to form a fluidized bed of the carrier particles, introducing a solution or dispersion of coating material in a carrier liquid into the fluidized bed whereby the carrier particles are contacted with a cloud of atomized liquid droplets of the coating material in a disperse state resulting in a homogenous distribution of the liquid droplets among the carrier particles, and maintaining the fluidized bed of carrier particles at a temperature and for a time sufficient to volatilize and evaporate the carrier liquid.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.