Toner aggregation processes
US5496676A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 27, 1995 |
| Grant date | Mar 5, 1996 |
| Priority date | — |
| Expiry date | Mar 27, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03G9/0804
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A process comprising: PA1 (i) preparing a pigment dispersion comprised of pigment, ionic surfactant, and optional charge control agent; PA1 (ii) mixing at least two resins in the form of latexes, each latex comprising a resin, ionic and nonionic surfactants and optionally a charge control agent, and wherein the ionic surfactant has a countercharge to the ionic surfactant of (i) to obtain a latex blend; PA1 (iii) shearing said pigment dispersion with the latex blend of (ii) comprised of resins, counterionic surfactant with a charge polarity of opposite sign to that of said ionic surfactant and a nonionic surfactant; PA1 (iv) heating the above sheared blends of (iii) below about the glass transition temperature (Tg) of the resin, to form electrostatically bound toner size aggregates with a narrow particle size distribution; and PA1 (v) subsequently adding further anionic surfactant solution to minimize further growth of the bound aggregates (vi); PA1 (vi) heating said bound aggregates above about the glass transition temperature Tg of the resin to form stable toner particles; and optionally PA1 (vii) separating and drying the toner.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.