| 摘要 |
Carrier particles for use in a developing material for electrostatic images comprise iron beads coated with a layer of butadiene polymer resin in which Fe3O4 powder is dispersed, the volume ratio of the polymer resin to Fe3O4 is from 1:2 to 4:1, and the butadiene polymer is cured by heating with an organic peroxide of from 0.5 to 5.0 parts by weight, based on the weight of the butadiene polymer, which comprises a homopolymer containing 1,2-polybutadiene units, or a homopolymer or copolymer of cyclized 1,4-cis-polybutadiene. The developing composition includes from 1% to 6% by weight, based on the weight of the carrier particles, of toner particles which generally comprise a bis-phenol A-epichlorohydrin type resin, carbon powder, a nigrosine dye, and either a styrene-n-butyl acrylate copolymer or a montan wax. |
