| 摘要 |
PURPOSE:To maintain a stable image density and triboelectrostatic charge quantity even in the case of copying many sheets at and under a high temp. and high humidity and to obtain stable copies free from scumming in the non- image parts by incorporating magnetic powder, polyester resin having <=5 mgKOH/g acid value and <=25mgKOH/g hydroxyl value, and specific metal- contg. monoazo dye into the carrier. CONSTITUTION:This carrier contains the magnetic powder, the polyester resin having <=5mgKOH/g acid value and <=25mgKOH/g hydroxyl value and the metal-contg. monoazo dye expressed by formula I. Ferromagnetic powders, for example, powders, such as gamma-Fe2O3, Fe3O4, iron powder, Co-contg. gamma-Fe2O3, and ferrite, are used as the magnetic powder. A small amt. of polar group-contg. polyolefin may be added to the carrier in order to enhance the uniform dispersibility of the magnetic powder. The stable image density and triboelectrostatic charge quantity are maintained in this way even in the case of copying the many sheets at and under the high temp. and high humidity. The stable copies having no scumming in the non-image parts are obtd. |
