| 摘要 |
The positively chargeable toner powder essentially comprises finely divided, coloured toner particles. The toner particles contain an insulating thermoplastic resin, colorant materials and a polarity-control agent; the thermoplastic resin comprises at least 50 % by weight of an epoxy resin having an epoxy equivalent weight of at least 10,000, where at least 5 % of the epoxide groups of the resin are able to react with a monofunctional carboxylic acid and/or a monofunctional phenol which, apart from the carboxyl or hydroxyl group, respectively, contain(s) no substituents which are able to react with the epoxide groups of the resin under the conditions of the preparation of the toner powder; at most 95 % of the epoxide groups of the resin are modified by intermolecular reaction or by crosslinking with the aid of a polyfunctional epoxy curing agent. |
