| 摘要 |
PURPOSE:To impart adequate triboelectrified charge to a toner by incorporating a microcarrier of a magnetic material dispersion type, toner contg. a prescribed resin and fine inorg. particles which are treated with a specific modified silicone compd. into a developer. CONSTITUTION:Particles of 10-50mum average grain size formed by dispersing and incorporating magnetic material particles into a styrene/acrylic copolymer (e.g.: styrene/n-butyl acrylate copolymer) are used for the carrier of the developer. Fine powder prepd. by dispersing a coloring agent, etc., into the binder consisting of the styrene/acrylic copolymer (e.g.: styrene/n-butyl acrylate/methyl methacrylate copolymer) is used for the toner. The fine inorg. particles (e.g.: silica particles) which are subjected to the surface treatment by >=1 kinds of amino modified silicone varnish, amino modified silicone rubber, amino modified silicone resin or the cured matter thereof and are electrostatically charged positive by friction with the carrier are added to the developer. |
