Toner used with electrophotography
US7144666B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 20, 2004 |
| Grant date | Dec 5, 2006 |
| Priority date | — |
| Expiry date | Sep 30, 2024 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03G9/09725
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A toner having toner particles containing a binder resin and a colorant; and a first external additive having 0.1 to 3.0 wt % of large silica particles with an average particle size of 20 to 200 nm; a second external additive having 0.1 to 3.0 wt % of small silica particles with an average particle size of 5 to 20 nm; a third external additive having 0.1 to 2.0 wt % of hydrophobic titanium dioxide microparticles with a resistance of 105 to 1012 Ωcm; and a fourth external additive having at least one of 0.1 to 2.0 wt % of conductive titanium dioxide particles with a resistance of 1 to 105 Ωcm and 0.1 to 2.0 wt % of positively chargeable aluminum oxide particles. Therefore, a thin toner layer with a uniform toner amount is formed on a toner carrier and stable charge distribution and toner flowability are maintained for a long time, thereby resulting in prevention of fog and toner scattering, and improvements in developing efficiency and toner durability.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.