Toner for developing an electrostatic image and process for producing a toner
US5985502A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 18, 1997 |
| Grant date | Nov 16, 1999 |
| Priority date | — |
| Expiry date | Dec 18, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03G9/08795
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A toner has at least 100 parts by weight of binder resin and 0.1 to 15 parts by weight of colorant. The toner has a number average particle size (Dn) of 0.5 to 6.0 .mu.m, a particle size distribution coefficient (volume average particle size (Dv) / number average particle size (Dn)) of 1.0 to 1.3 and a variation coefficient of particle number distribution of 20% or less. The toner contains 0.1 to 5.0% by weight of methanol-soluble resin component extracted by the first Soxhlet extraction with methanol and 50 to 99% by weight of THF-soluble resin component extracted by a second Soxhlet extraction with tetrahydrofuran (THF) after the Soxhlet extraction with methanol, wherein the maximum glass transition point (Tg.sub.2) of the methanol-soluble resin component and the glass transition point (Tg.sub.1) of the THF-soluble resin component satisfies the following relation; EQU 0 (.degree. C.)<Tg.sub.2 -Tg.sub.1 .ltoreq.150 (.degree. C.) and EQU 50 (.degree. C.).ltoreq.Tg.sub.1.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.