| 摘要 |
A monomer for a shell or a mixture of at least two monomers for a shell was suspension polymerized in the presence of core particles and a polymerization initiator to obtain polymer particles, wherein said core particles are formed of a polymer obtained by polymerization of a monomer for a core or a mixture of at least two monomers for a core and containing a colorant, wherein said monomer for a shell or mixture of monomers for a shell is one which gives upon polymerization a polymer having a glass transition temperature higher than that of the polymer forming the core particle, and wherein said polymerization initiator is represented by the following formula 1: wherein X1, X2, X3 and X4 independently represent oxygen atom, sulfur atom, >NR (wherein R is hydrogen atom, alkyl group, or group); R1, R2, R3, R4, R5 and R6 independently represent alkyl group, aryl group, or alkyl or aryl group having at least one substituent which is -OR, -OH, -NHR, or -NR2(wherein R is alkyl group or aryl group), and n and m independently represent an integer of 1 to 10. An outer additive was applied on the polymer particle to obtain a polymerized toner. This polymerized toner has low fixing temperature, excellent overhead projector transparency, good shelf stability, and exhibiting a less pronounced reduction in electric charge under conditions of high humidity and high temperature.
|
