| 摘要 |
PURPOSE:To improve charge controllability and durability and to obtain a sharp image by incorporating an electron-donative material having a specific ionization potential value in a toner and coating a carrier with a styrene/acrylic resin. CONSTITUTION:An electron-donative material having <=7.8eV ionization potential value, for example, triphenyl amine, is incorporated as a charge control agent in a toner, at about 0.1-10wt% basing on the weight of the binder resin. A carrier is used after a styrene/acrylic resin (SA resin) is coated thereon. The electron- donative material is incorporated in the toner and the carrier layer is formed of the SA resin having relatively high electron acceptivity in such a way and therefore the donation and acceptance of the electric charge between the electron- donative material and the carrier are smoothly accomplished, whereby the uniform electrostatic charge is impressed over the entire part of the developer and the sharp image is obtd. without filming of the toner. The durability of the developer is excellent. Such developer is suitable for various types of photosensitive bodies having negative electrostatic charging property, such as a photosensitive body having an a-Si vapor deposited layer. |
