| 摘要 |
PURPOSE:To obtain the black toner which has a high coloring power, forms a deep-black image and is sufficient in electrostatic charge by incorporating a resin, carbon black having a small grain size and specific pigment into the black toner. CONSTITUTION:This toner contains the resin, the carbon black having >=80m<2>/g BET surface area and <=50mmu particle size and the pigment expressed by formula I. In the formula, R, R' denote 1 to 5C alkylene group; however, the case in which all of X1 to H4 are -H is excluded. The total coloring agent content of the carbon black and the compd. expressed by the formula I is confined to <=15pts.wt. per 100pts.wt. resin and the ratio (based on weight) of the compd. of the formula I to be added with the amt. of the particle is specified to 100/10 to 100/50. A reddish color increases and the sufficient electrostatic charge is not obtd. in case of <100/10 ratio. The color shifts from the black to a cyan color and the black images are not obtainable when the ratio exceeds 100/50. The black image having the high coloring power is obtd. in this way and the toner which is sufficient in the electrostatic charge is obtd. |
