| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain yellow toner with little decolorization, excellent color reproducibility and little changes in the charge amt. against environmental changes from a low temp. low humidity to a high temp. high humidity by incorporating a specified compd. as a coloring agent. SOLUTION: This toner essentially consists of a coloring agent and a binder resin. As for the coloring agent, a compd. expressed by formula is incorporated into the toner. As for the binder resin, a polyester resin is preferable because it is excellent in coloring ability and durability against environmental changes. The polyester resin is obtd., for example, by ester-coupling a polyvalent alcohol and a polybasic acid containing dicarboxylic acid as the essential components. Thereby, the obtd. toner shows little decolorization as a yellow toner, excellent color reproducibility and little changes in the charge amt. against environmental changes from a low temp. low humidity to a high temp. high humidity. Further, the toner gives good and stable transfer image quality and when it is used together with toner containing various color pigments such as cyan, magenta and yellow in so-called multicolor printing, it can provide the quality of a sharp transfer image extremely similar to natural colors.</p> |
