| 摘要 |
PURPOSE:To obtain a toner by which always good images are obtained by containing an amorphous inorg. solid material contg. silicate in the surfaces of magnetic powder. CONSTITUTION:Magnetic powder is put in an aq. soln. of a 2.1-3.5mol range of SiO2 based on 1mol an alkali metal oxide obtd. by treating the product prepd. by heating and melting a mixture of, for example, silica sand and soda ash in a low pressure autoclave, and after these are agitated for about 3hr at an ordinary temp., the mixture is dried at about 60 deg.C, whereby the magnetic powder contg. amorphous silicate solids in the surfaces is prepd. This treated magnetic powder, a binder such as polystyrene copolymer, and necessary additives such as coloring agents are added, and after these are melted and mixed, the mixture is cooled, ground and sieved, whereby a magnetic toner is obtained. The resultant toner retains stable electrostatic charging quantity even in high humidity, and yields always stable and good images. |
