| 摘要 |
<p>PURPOSE:To obtain the developer compsn. which has the excellent stability of a toner with lapse of time, is fast in rising of electrostatic charge, is easy in the control of the electrostatic charge quantity of the toner and is narrow in a charge distribution by using a carrier having a specific coating material and the toner contg. a specific charge control agent. CONSTITUTION:This developer consists of the carrier coated with a material 2 having >=1.20 value of 1+cos theta determined from the contact angle (theta) 5 with water 3 and the toner contg. the charge control agent having a salt structure. The positive or negative ions of the charge control agent having the salt structure existing in the toner or on the toner are liable to migrate to the carrier surface and, therefore, the toner can be surely electrified positive or negative. As a result, the stable electrostatic charge quantity of the toner is obtd. The material having >=1.20 value of 1+cos theta determined from the contact angle (theta) 5 with water 3 is obtd. by providing polar groups in the resin. Such polar groups include a hydroxyl group, carboxyl group, etc.</p> |
