Electrostatic image developer

Abstract

Abstract PURPOSE:To obtain a developer good in fluidity and chargeability, and superior in durability, by adding a fine silica powder prepared by the wet method and made hydrophobic with silicone oil, and allowing said powder to be stably held for a long time. CONSTITUTION:A fine silica powder on the market prepared by the wet method having 0.01-2mum average primary diameter, and preferably >=85% SiO2 content is dispersed into a soln. of silicone oil dissolved in toluene or the like so as to allow 100g silica to adsorb 0.01-10g silicone oil. This dried hydrophobic silica fine powder is added to a composn. of a binder resin, one or both of chlorinated paraffin and paraffin wax, colorant, etc. in (0.01-10):100wt. ratio, thus permitting the obtained developer to be able to stably form a good for a long time.

Inventors

• 👤 Hiroyuki Suematsu
• 👤 末松　浩之

Bibliographic Details