POLYESTER RESIN FOR TONER, ITS PRODUCTION AND ELECTROPHOTOGRAPHIC TONER USING IT

摘要

PROBLEM TO BE SOLVED: To provide an electrophotographic toner which can be fixed at low fixing temp., which causes no problem about offset in practical use which has excellent fixing strength to a transfer paper. SOLUTION: This polyester resin has <=5wt.% THF insoluble component. In the distribution of molecules in a THF-soluble component, the proportion of a ultrahigh mol.wt. as >=1×10<6> is between >=1wt.% and >=10wt.% and the proportion of high mol.wt. as >=1×10<5> is between >=10wt.% and <=20wt.%. The proportion W1 of a low mol.wt. molecule as <1×10<4> and the proportion W2 of a medium mol.wt. as between >=1×10<4> and <1×10<5> are in the relation of W1 >W2 .