Latex processes
US6503680B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 29, 2001 |
| Grant date | Jan 7, 2003 |
| Priority date | — |
| Expiry date | Aug 29, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03G9/081
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A process for the preparation of a latex polymer consistent with E/A (emulsion/aggregation/coalescence) toner manufacture. The process utilizes a standard (universal) latex composition and involves chain-transfer agent partitioning, emulsion polymerization that provides a latex polymer with a wide range of molecular properties. In particular, the process customizes a wide range Mw (weight average molecular weight) latex, without substantially varying the Mn (number average molecular weight) and hence, without substantially varying Tg (glass transition temperature) such that good toner performance is maintained. In a preferred process, a latex polymer is prepared by mixing a seed particle latex, generated by aqueous emulsion polymerization of a first portion of a monomer emulsion, with a second portion of the monomer emulsion and at least one chain-transfer agent. The mixing is done in the presence of a free-radical initiator and heated, and wherein the monomer emulsion comprises a mixture of polymerization reagents of at least one monomer, at least one chain-transfer agent, at least one surfactant, and water. This process may be applied to core-shell polymerization as well. These l…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.