TONER FOR TWO-COMPONENT MAGNETIC DEVELOPER EXCELLENT IN SPENDING RESISTANCE

摘要

PURPOSE:To obtain a toner for a charge controlling agent-free positive charge type two-component magnetic developer excellent in spending resistance, prolonging the service life of the toner and carrier, not contg. a migrating charge controlling agent in the toner particle. and capable of increasing apparent development sensitivity without scattering the toner at the time of development and to obtain a charge controlling agent-free positive charge type two-component magnetic developer ensuring efficient transfer from the surface of a photoreceptor to paper though a migrating charge controlling agent is not contained. CONSTITUTION:A copolymerized resin having cationic polar groups or a resin compsn. is used as a fixing resin medium, magnetic powder is incorporated into the resin medium by 0.1-5pts.wt. per 100pts. wt. of the resin medium and the resulting toner is regulated so that the absorbance of the absorption peak of a liq. obtd. by extracting the toner with methanol in the wavelength range of 400-700nm is made practically zero. Spacer particles having 0.05-1mum particle diameter are allowed to exist in a flowability improver added to the toner.