| 摘要 |
<p>PURPOSE:To lower the resistance of a resin coat carrier which is a negative charge carrier for positive charge toner and to improve image quality due to sufficient effect of a developing electrode from a sleeve by adding conductive particulates having the pH value higher than a specific value to the surface of a resin, with which the surf ace of a magnetic material core is applied, and by keeping the volume resistivity at a specific value or less. CONSTITUTION:The surface of the magnetic material core is applied with the resin and the conductive particulates of >=pH7.5 are added on the surface of the resin to keep the volume resistivity at <=10<5>pH.Cm. The carrier durability and static chargeability are stabilized because the surface of the magnetic material core is applied with the resin in such a manner. Further, the quantity of negative electrostatic charge on the surface of the resin can be increased because the conductive particulates being >=#7.5 are added on the surface of the resin of the resin coat carrier. Further, the electric resistance of the carrier is reduced due to the electrical conductivity of carbon black dispersedly stuck or fixed approximately uniformly to the surface of the carrier. As a result, sticking of the toner to a latent image part is stably executed due to the electrode effect of the sleeve holding the developer.</p> |
