| 摘要 |
PURPOSE:To improve electric chargeability and photoconductivity and to enhance photosensitivity to infrared rays by dispersing zinc oxide, a colorant, and a specified pigment into a binder resin. CONSTITUTION:The binder resin contains, preferably, 100-300pts.wt. of zinc oxide as the photoconductive material per 100pts.wt. of the binder resin and as the sensitizing pigment a cyanine pigment represented by formula I, prefer ably, in an amount of 0.05-0.15wt.% of the zinc oxide, both dispersed into the binder resin. If the zinc oxide is added more than 300pts.wt., the produced toner deteriorates in chargeability, and if the zinc oxide is added less than 300pts.wt., the photoconductivity decreases, and if the cyanine pigment is added more than 0.15wt.% of the zinc oxide, chargeability of the toner is impaired, and if below 0.05wt.%, a sufficient sensitizing effect cannot be obtained, thus permitting the obtained toner to have superior photosensitivity to light in the near infrared region and the other infrared region, and to form a good image free from fog and sharp in contrast. In formula I, R is CH3, C2H5, CH2COOH, C2H4COOH, or CH2=CHCH2; X is I, Br, Cl, or ClO4; a group of formula II is a group of formula III or IV; and a group of formula V is a group of formula VI or VII. |
