Kao Corporation

Kao Soap Company, Ltd.

Masao Niki

Yukinaga Yokota

Hiroshi Fukusaki

Koji Akiyama

Shinichiro Yasuda

Kazuhiko Okabe

Yutaka Kanamaru

Zenbei Meiwa

Jun-ichi Furukawa

Hiroshi Fukuzaki

An electrophotographic dry developer which comprises a carrier and toner particles comprising a binder resin comprising (A) a polyester resin and (B) a styrene-acrylic resin obtained by co-polymerizing a monomer having an amino group, at a weight ratio of (A) to (B) ranging from 55:45 to 95:5, both resin (A) and resin (B) and a dyestuff or pigment of chromatic color. It is positively charageable and serves for color electrophotography.

Electrophotographic dry developer

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.

Dry developer composition comprising polymer binder resin and colorant

A toner for development of an electrostatically charged image which comprises at least a binder, a colorant and a compound having the formula (I) or (III): ##STR1## wherein A represents a phenol group-containing compound residue,

Toner for development of electrostatically charged image

A film-forming liquid resin dispersion is prepared by dispersing a surface active polyester in a collidal form in water or an aqueous solution containing a small amount of a base and grafting a vinyl compound monomer and/or an acrylic or methacrylic acid ester monomer to the surface active polyester.

Process for preparation of grafted unsaturated polyester liquid resin

An oil-in-water emulsion of a vinyl polymer is prepared by emulsion polymerizing a vinyl monomer in the presence of a polyester having a surface active property.

Process for preparation of oil-in-water emulsions of vinyl polymers

A liquid resinous composition is prepared by reacting a dibasic acid component containing .alpha.,.beta.-unsaturated basic acid with a glycol component to form an unsaturated polyester having an acid value of at least 10 and a molecular weight of 1,000 to 10,000, mixing the polyester with a basic substance to neutralize unreacted carboxyl groups and then subjecting the resulting water solubilized unsaturated polyester to addition reaction with a monovinyl compound. The composition is suited for adhesive, coating, printing ink, and binder.

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Wakayama, Japan

Masao Niki