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:
Jul. 04, 1989
Filed:
Dec. 30, 1983
Masao Niki, Wakayama, JP;
Zenbei Meiwa, Wakayama, JP;
Kao Corporation, Tokyo, JP;
Abstract
A dry developer composition for electrophotography is disclosed capable of retaining a positive charge and comprises a binder resin and a colorant, the binder resin being a polymer obtained by polymerizing, in a suspension, (A) 98 to 99.95 parts by weight of a hydrophobic copolymerizable monomer and (B) 0.05 to 2.0 parts by weight of a tertiary amino group-containing copolymerizable monomer having the formula (1): ##STR1## in which R1 is hydrogen or methyl, X is --COO-- or --CONH--, R2 and R3 are each an alkyl having 1 to 4 carbon atoms or an aryl and n is an integer of 1 to 4, in the presence of (C) 0.5 to 5.0 parts by weight of an azonitrile polymerization initiator.