| 摘要 |
PURPOSE:To obtain stable sharp images high in density for a long period by using particles small in diameter obtained by dispersing a fine magnetic powder into a binder made of cross-linked polymer as a carrier in developing a latent image with a binary developer. CONSTITUTION:A monomer having a cross-linkable functional group on the side chain, such as 2-hydroxyethyl acrylate, is homo- or co-polymerized to prepare a cross-linkable polymer having cross-linkable functional groups on the side chains. A carrier having an average particle diameter of 10-50mum is prepared by uniformly mixing this cross-linkable polymer, a cross-linking agent, such as tolylenediisocyanante, a fine magnetic powder, such as magnetite, and other necessary additives, further, melting and kneading the mixture with a heating roller, allowing it to cross-link with each other, then, cooling, pulverizing, and classifying it. A latent image is developed by using a binary developer made of a combination of this carrier and a toner to obtain an image. |
