The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 11, 1990
Filed:
Dec. 22, 1989
Fuji Photo Film Co., Ltd., Kanagawa, JP;
Abstract
A liquid developer for electrostatic photography comprising a resin dispersed in a non-aqueous solvent having an electric resistance of at least 10.sup.9 .OMEGA.cm and a dielectric constant of not higher than 3.5, wherein the dispersed resin is a polymer resin obtained by polymerizing a solution containing at least one mono-functional monomer (A) which is soluble in the aforesaid non-aqueous solvent but becomes insoluble after being polymerized, in the presence of at least one resin which is soluble in the aforesaid non-aqueous solvent and does not have a graft group polumerizable with the monomer and at least one oligomer (B) having a number average molecular weight of not more than 1.times.10.sup.4 and having at least one polar group selected from a carboxy group, a sulfo group, a hydroxy group, a formyl group, an amino group, a phosphono group, and ##STR1## wherein R.sup.0 represents a hydrocarbon group or --OR.sup.1, (wherein R.sup.1 represents a hydrocarbon group) bonded to one terminal only of the main chain of a polymer composed of a recurring unit represented by following formula (I): ##STR2## wherein V.sup.1, R.sup.2, a.sup.1 and a.sup.2 are as defined in the specification. The liquid developer is excellent in dispersion stability, re-dispersibilty, and fixability, and also is capable of forming an offset printing plate having excellent ink-receptivity for printing ink and excellent printing durability by electrophotography.