Mitsui Chemicals, Inc.

Kyoji Kuroda

Masahiro Kaneko

Hiroaki Narisawa

Mitsuo Kawata

Shinichi Asai

Makoto Someda

A nitrile resin for a carrier resulting from graft-copolymerization of 100 parts by weight of a monomer mixture containing unsaturated nitrile and alkyl acrylate in the presence of 1 to 30 parts by weight of a rubber-like polymer containing 50% by weight or more of conjugated diene units. The nitrile resin comprises having a glass transition temperature of 50 to 69.degree. C., having a matrix component except rubber ingredient containing 45 to 80% by weight of unsaturated nitrile units and 20 to 55% by weight of alkyl acrylate units and having a weight average molecular weight of 30,000 to 150,000. The invention further relates to a preparation process of nitrile resin and an electrophotographic carrier containing the nitrile resin. The nitrile resin for a carrier of the invention has an excellent processing ability in the carrier preparation step and good balance of electrostatic charge stability of the carrier. Consequently, the resin is highly suitable for use in the electrophotographic carrier.

Nitrile resin for electro-photographic carrier and preparation process

A nitrile resin composition having excellent transparency, antistatic properties and practical physical properties. The composition comprises (A) 80 to 97 wt. % of a nitrile resin which is obtained by graft copolymerization, in the presence of 3 to 30 parts by weight of a rubbery polymer containing at least 50 wt. % of a conjugated diene unit, of 100 parts by weight of a monomer mixture containing an unsaturated nitrile and an alkyl methacrylate, and has, as a matrix component, 65 to 80 wt. % of an unsaturated nitrile unit and 20 to 35 wt. % in total of an alkyl (meth)acrylate unit and a unit of a further monomer copolymerizable with the unsaturated nitrile and alkyl (meth)acrylate; and (B) 3 to 20 wt. % of a polyether ester amide, wherein the ratio of the melt viscosity of the component (A) to that of the component (B) at 210.degree. C. is 0.5 to 5 at a shear rate of 10.sup.2 sec.sup.-1 and 0.5 to 3 at a shear rate of 10.sup.3 sec.sup.-1 and the difference of the refractive index between the matrix component (A) to the component (B) is 0.2 or less.

Growing community of inventors

Aichi-ken, Japan

Kyoji Kuroda