Liquid developer for electrostatic photography
US4840865A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 29, 1986 |
| Grant date | Jun 20, 1989 |
| Priority date | — |
| Expiry date | Dec 29, 2006 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03G9/13
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A liquid developer for electrostatic photography is disclosed, comprising a non-aqueous solvent having electrical resistivity of not less than 10.sup.9 .OMEGA..cm and a dielectric constant of not more than 3.5 having dispersed therein at least a resin, wherein said resin is a copolymer resin obtained by subjecting a solution containing (A) at least one of monofunctional monomer which is soluble in said solvent but insolubilized upon polymerization and (B) at least one of monomers having at least two polar groups and/or polar linking groups represented by formula (I): ##STR1## wherein V, Y, R.sub.1, R.sub.2, X.sub.1, X.sub.2, a.sub.1, and a.sub.2 are defined in the specification, to a polymerization reaction in the presence of a resin which is soluble in said solvent and contains no graft group polymerizable with said monomers. The developer is excellent in dispersion stability, redispersibility and fixing properties and is capable of producing a master plate for offset printing having excellent ink sensitivity and printing durability.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.