Toner for developing electrostatic image and process for production thereof
US5338638A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 26, 1991 |
| Grant date | Aug 16, 1994 |
| Priority date | — |
| Expiry date | Nov 26, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03G9/08795
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A toner for developing an electrostatic image is provided as a pulverized mixture including a binder resin and a colorant. The binder resin is characterized by a molecular weight distribution on a GPC chromatogram of its tetrahydrofuran (THF)-soluble resin content including at least 15% and below 35% of a resin component in a molecular weight region of at most 5000 and at least 3 wt. % of a resin component in a molecular weight region of at least 5.times.10.sup.6 and showing a main peak in a molecular weight region of 5000 to 10.sup.5. The binder resin also has an acid value of 2-100 mg KOH/g. The THF-soluble resin component in the molecular weight region of at least 5.times.10.sup.6 is enriched during a melt-kneading step during the toner production.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.