Method of electrostatic printing and toner used in such method
US5230979A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 7, 1991 |
| Grant date | Jul 27, 1993 |
| Priority date | — |
| Expiry date | Jun 7, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03G9/125
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A liquid toner for developing electrostatic latent images, at speeds in excess of 100 ft./min., by electrophoretic movement of pre-charged particles of a thermoplastic polymer in a nonpolar carrier liquid, which reduces drag is disclosed wherein the particles are present in about 10% by weight of the weight of the carrier liquid, and no more than 10% by volume of such toner particles having a size less than 1.0 micron as measured by an Horiba Capa-700. The nonpolar liquid has, typically, a volume resistivity in excess of 10.sup.9 ohm centimeters, a dielectric constant no greater than 3.5, and a vapor pressure of less than 10 millimeters of Mercury at 25 degrees C. The toner composition also includes a quantity of charge director for imparting an electrostatic charge of predetermined polarity to said particles. The toner particles may have a plurality of fibers integrally extending therefrom. Also disclosed is a method of electrostatic printing, at speeds of at least 100 feet-minute, using such liquid developers.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.