| 摘要 |
PURPOSE:To provide a developer which exhibits a substantial negative polarity even with a small amt. and has complementary colorability with carbon black as well by using a compd. having a high negative charge effect. CONSTITUTION:The compd. expressed by the formula is incorporated in a developer for electrophotography. R in the formula I is any among the formulas II-IV. The diazo compd. expressed by the formula I is synthesized by a method consisting of subjecting a diphenyl compd. or halogenated diphenyl compd. into nitroso reaction with an aq. sodium nitride soln. under the acidity of hydrochloric acid at a low temp. of <=5 deg.C then making an amino group by the reduction reaction of iron powder or zinc powder and further synthesizing the diazo compd. of diphenyl by diazo reaction. The diazo compd. is brought into coupling reaction with a coupler having a substituent R in an alkali state. All the resins used for an ordinary dry type toner are usable for the resin to be used and in general the resin may be selected by taking the nature as a toner, for example, coloring, transparency, adhesion, fluidity, grindability, etc. into consideration. |
