ELECTROSTATIC IMAGE DEVELOPER

摘要

PURPOSE:To stably form an image having good image quality without fogging at a high density by incorporating a copolymer of an acrylic monomer and styrene monomer having an electron withdrawing substituent as a binder into a toner and providing a coating layer formed by curing a silicone resin onto the particle surface of a carrier. CONSTITUTION:An electrostatic image developer is constituted of the toner formed by contg. the copolymer of the acrylic monomer and styrene monomer having the electron withdrawing substituent as the binder and the carrier formed by providing the coating layer formed by curing of the silicone resin onto the surface of the carrier core material. The electron withdrawing substituent is exemplified by a fluorine atom, bromine atom, nitro group, etc. The copolymer to be used as the binder contains preferably >=10wt% high mol.wt. component having >=100,000mol.wt. The performance to prevent the generation of the so- called offset in which part of the toner constituting the image is transferred onto the surface of a fixing roller in the stage of fixing and that the transferred toner is transferred again onto transfer paper carried to the fixing roller to stain the image is obtd.