Method to media mill particles using crosslinked polymer media and organic solvent
US5902711A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 25, 1997 |
| Grant date | May 11, 1999 |
| Priority date | — |
| Expiry date | Jun 25, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03G9/0819
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A process of forming milled solid particles of a compound comprising milling solid particles of the compound in a liquid organic medium continuous phase in the presence of polymeric milling media to reduce the average size of the compound particles, wherein the liquid continuous phase comprises a solvent for the milling media polymer in the uncrosslinked form and the milling media is crosslinked sufficiently to prevent 50 vol. % swelling of the polymeric milling media in the liquid continuous phase within four hours at 25.degree. C. In various preferred embodiments of the invention, polymeric milling media having a mean particle size of less than about 100 .mu.m in the unswelled state (i.e., prior to addition to the liquid organic continuous phase) is used; the compound particles are milled to an average particle size of less than 100 nm; the compound comprises electrophotographic toner pigment; the liquid continuous phase comprises an ethylenically unsaturated polymerizable monomer; and the milling media polymer comprises polymerized styrene and divinylbenzene monomers. In an additional preferred embodiment of the invention wherein the compound comprises electrophotographic toner …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.