Developer and image forming device
US4957840A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 25, 1988 |
| Grant date | Sep 18, 1990 |
| Priority date | — |
| Expiry date | Oct 25, 2008 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S430/104
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A developer for developing electrostatic images, comprising a magnetic toner comprising a binder resin and magnetic powder, the developer containing 17-60% by number of magnetic toner particles of 5 microns or smaller, containing 1-23% by number of magnetic toner particles of 8-12.7 microns, and containing 2.0% by volume or less of magnetic toner particles of 16 microns or larger; wherein the magnetic toner has a volume-average particle size of 4-9 microns, and the magnetic toner particles of 5 microns or smaller have a particle size distribution satisfying the following formula: EQU N/V=-0.04N+k, wherein N denotes % by number of magnetic toner particles of 5 micron or smaller, V denotes % by volume of magnetic toner particles of 5 microns or smaller, k denotes a positive number of 4.5-6.5, and N denotes a positive number of 17-60.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.