TONER FOR DEVELOPING ELECTROSTATIC CHARGE IMAGE, ELECTROSTATIC CHARGE IMAGE DEVELOPER AND IMAGE FORMING METHOD

摘要

PROBLEM TO BE SOLVED: To obtain a toner excellent in flowability and caking resistance, having moderate negative chargeability and capable of maintaining stable chargeability for a long time even at high temp. and humidity and at low temp. and humidity. SOLUTION: This toner contains toner particles and fine titanium oxide particles coated with 0.1-2.0wt.% (expressed in terms of Al2 O3 ) aluminum or alumina coating films and further treated with a surface treating agent. A compd. selected from among an anionic surfactant, an amphoteric surfactant, a silane coupling agent and silicone oil is used as the surface treating agent and the treatment is preferably carried out in a soln. This toner is mixed with a resin coated carrier and used as the objective electrostatic charge image developer. It is used in an image forming method adopting a developing process in which a developer is held on a developer holder placed opposite to an electrostatic latent image holder and development is carried out.