Electrostatic latent image-developing toner containing specified toner particles and specified external additives
US5976750A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 27, 1998 |
| Grant date | Nov 2, 1999 |
| Priority date | — |
| Expiry date | Jan 27, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03G9/09708
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The present invention provides an electrostatic latent developing toner which comprises: PA1 toner particles containing a colorant and a binder resin, the toner particles satisfying the following relation: EQU 1.45-0.05 D.sub.50 .ltoreq.D.sub.25 /D.sub.75 .ltoreq.1.75-0.05D.sub.50(1) (in which D.sub.25, D.sub.50 and D.sub.75 denote toner particle sizes such that when the toner particles are integrated from the larger particle side, the volume percentages of toner particles of respective particle sizes are 25%, 50%, and 75% based on the total volume of the toner particles), particle size D.sub.50 being within the range of from 3 to 7 .mu.m; or PA1 the toner particles having a volume-mean particle size of 3 to 7 .mu.m and a shape factor SF1 of 100 to 130 as expressed by the following relation (2): EQU SF1={100 .pi..times.(max length).sup.2 }/{4.times.(area)} (2) (in which, "max length" represents mean value of maximum lengths of projected toner particle images, and "area" represents mean value of projected toner particle areas); and PA1 an external additive admixed with the toner particles, the external additive containing hydrophobic inorganic fine particles A having a number-mean p…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.