Patent ID: 6136490
Filing Date: 2000-10-24
Classification: G03G

Abstract:
A method for producing a polymerized toner comprising polymer particles, which comprises the steps ofsuspension polymerizing a monomer for a core or a mixture of at least two monomers for a core to obtain core particles, andsuspension polymerizing a monomer for a shell or a mixture of at least two monomers for a shell in a dispersion medium in the presence of the core particles dispersed in said dispersion medium and with the aid of a polymerization initiator added to said dispersion medium,whereinsaid 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 particles, andsaid polymerization initiator is represented by the following formula 1: ##STR3## wherein X.sup.1, X.sup.2, X.sup.3 and X.sup.4 independently represent oxygen atom, sulfur atom, >NR, wherein R is hydrogen atom, alkyl group, or aryl group;R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5 and R.sup.6 independently represent alkyl group, aryl group, or alkyl or aryl group having at least one substituent which is --OR, --OH, --NHR, or --NR.sub.2, wherein R is alkyl group or aryl group, andn and m independently represent an integer of 1 to 10.