| 摘要 |
<p>PURPOSE:To obtain copied images which have an excellent flow property and preservable property, has good electrostatic chargeability and the property to sustain this electrostatic charge and lessens the degradation in image density and fogging even in continuous copying by mixing specific silica and polishing agent particles with toner particles. CONSTITUTION:This toner contains the toner particles having a thermoplastic resin, the positively charged silica, the negatively charged silica, and the polishing particles having the hardness higher than the particles of the surface of a photosensitive body and 0.2 to 100mum average grain size. The polishing particles are preferably cerium oxide, alumina, silicon carbide, etc. More preferably the amt. of these particles to, be added is obtd. as an empirical numerical value by an experiment and is, for example, 0.01 to 10wt.% of the weight of the toner particles in a developer. The silica treated with a nitrogenous coupling agent, etc., is usable as the positively charged silica. Hydrophobic colloidal silica is usable as the negatively charged silica.</p> |
