| 摘要 |
PURPOSE:To improve the pressure fixability of a microcapsule type toner and to improve offset resistance by polymerizing a vinyl monomer to polymer by using >=2 kinds of polymn. initiators having different half-value periods and incorporating the polymer into a core material. CONSTITUTION:The vinyl monomer, for example, lauryl methacrylate or the like is polymerized by the slow polymn. initiator A and the quick polymn. initiator B. Benzoyl peroxide, etc. are used for the initiator A and 2, 2'azobis-(2, 4- dimethyl valeronitrile), etc. are used for the initiator B. The ratio of the half- value periods tauA and tauB of the respective initiators is made 10-10<6>. A coloring material is added to the polymer in the state of polymn. and the monomer is polymerized. Such polymer is incorporated into the core material. The outside wall is coated with a hard resin such as epoxy resin or polyamide resin, by which the capsule type toner is obtd. The mol. wt. distribution of the polymer of the core material is controlled and therefore the resultant toner has good pressure fixability and is easily produced. |
