Fujikura Kasei Co., Ltd.

Akira Otsu

Kenji Sano

Hiroshi Nagase

Hikoji Ueda

Katuyuki Takano

A positively chargeable toner for use in dry electrophotography, said toner comprising (A) a resinous binder composed of at least one resin selected from copolymers of styrene and/or alpha-methylstyrene with alkyl (meth)acrylates, polyester resins and epoxy resins, (B) 1 to 100 parts by weight, per 100 parts by weight of the resinous binder, of a copolymer containing a quaternary ammonium salt group, said copolymer having a weight average molecular weight of from 2,000 to 10,000 and composed of 65 to 97% by weight of recurring units represented by the formula ##STR1## wherein R.sub.1 represents a hydrogen atom or a methyl group, and 35 to 3% by weight of recurring units represented by the formula ##STR2## wherein R.sub.2 represents a hydrogen atom or a methyl group, R.sub.3 represents an alkylene group, and each of R.sub.4, R.sub.5 and R.sub.6 represents an alkyl group, and (C) a coloring agent.

Positively chargeable toner for use in dry electrophotography

A process for producing a resin composition which comprises suspension-polymerizing at least one vinyl monomer in an aqueous medium in the presence of a dispersing agent, said suspension polymerization being carried out using a nonionic dispersant as said dispersing agent in the presence of a high-molecular-weight vinyl polymer having a weight average molecular weight of at least 500,000 obtained by emulsion polymerization.

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Tokyo, Japan

Akira Otsu