Dry toner for high speed electrophotography
US5185229A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 22, 1991 |
| Grant date | Feb 9, 1993 |
| Priority date | — |
| Expiry date | Jan 22, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03G9/08797
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Dry toner for electrophotography in the form of colored particles, each particle being composed of a colored core portion having an average diameter of 5 to 20.mu. and comprising as main ingredients, a coloring material and heat-meltable resin having a flow initiation temperature of 120.degree. C. to 160.degree. C., and a covering shell portion of a vinyl resin mixture of a comparatively low molecular weight component and a high molecular weight component, each having the maximum value in the molecular weight distribution curve obtained by gel-permeation chromatography of 8.times.10.sup.3 to 3.times.10.sup.4 and 8.times.10.sup.4 to 5.times.10.sup.5, respectively, and present in a ratio of Mw/Mn=5.0 or more; the weight ratio of said vinyl resins to the total weight of said core and shell portions being 8 to 25% by weight. The present dry toner is particularly useful for use in a high speed electrography.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.