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. 17, 1991
Filed:
Feb. 07, 1990
Eiichi Kato, Shizuoka, JP;
Hideyuki Hattori, Shizuoka, JP;
Fuji Photo Film Co., Ltd., Kanagawa, JP;
Abstract
A liquid developer for electrostatic photography is disclosed. The liquid developer comprises resin grains 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 grains are copolymer resin grains obtained by polymerizing a solution containing at least one kind of a monofunctional monomer (A), which is soluble in the above non-aqueous solvent but becomes insoluble therein by being polymerized, in the presence of a dispersion-stabilizing resin soluble in the non-aqueous solvent and an oligomer (B) having a number average molecular weight of not more than 1.times.10.sup.4. The dispersion-stabilizing resin is a polymer containing at least a recurring unit represented by the formula (I) described in the specification, a part of which has been crosslinked, and has a double bond group which is copolymerizable with the monofunctional monomer (A) and which is bonded to only one terminal of at least one polymer main chain, and the oligomer (B) is a polymer comprising a recurring unit represented by the formula (II) described in the specification and has at least one kind of a polar group. The light developer according to the present invention is excellent in re-dispersibility, storability, stability image-reproducibility, and fixability.