| 摘要 |
PURPOSE:To improve melt kneadability and durability by incorporating a metal or its oxide or the like in a copolymer obtained by polymerizing monomers contg. an aminoacrylic monomer in the presence of a specified polymerization initiator to form a positively electrifiable toner. CONSTITUTION:The copolymer is obtained by copolymerizing monomers contg. an aminoacrylic monomer, such as dimethylaminoethyl acrylate, in an amt. of 2-15wt%, and as other monomers, styrene or acrylic type monomers or the like in the presence of a polymerization initiator represented by the formula shown here, R1-R4 being a 1-8C satd. hydrocarbon group, and at least one of them being a >=2C group. This copolymer is added together with a metal, metal oxide, metal sulfide, metal halide, or the like to the positively electrifiable toner to regulate its saturation magnetization to <=10emu/g in an external magnetic field of 5,000Oe, and the addition of a specified aminoacrylate type copolymer into the positively electrifiable toner permits pulverizability, toner scattering resistance, and electrifiability to be improved. |
