| 摘要 |
PURPOSE:To obtain toner powder having unified viscosity and shape by drawing out the molten and kneaded matter of a raw material consisting of a thermoplastic high polymer and inorg. material into an extremely fine fiber shape, fixing preliminarily the biaxial size among the three dimensions, bundling many pieces thereof and cutting short the bundle in the triaxial direction. CONSTITUTION:Bisphenol polyester resin and carbon black are melted and kneaded by a twin-screw extruder and thereafter the mixture is molded into the fiber shape having about 5 micron diameter in the section by a melt spinner. Many pieces of such fibers are bundled and are so cut that the length in microtome attains 90mum. The cut fibers are spheroidized by a hot air spheroidizing device, by which a toner is obtd. The toner is made into a two-component developer and is used for copying of 10,000 sheets with a copying machine. The change in optical density is small and the durability of the toner is excellent as a result of the discrimination made for the optical density of the image planes at every 1,000 sheets thereof. |
