| 摘要 |
<p>PROBLEM TO BE SOLVED: To stabilize the electrostatic charge and transfer of a toner over a long period of time and to form a stable image free from fog and unevenness in density by incorporating carbon black of a specified pH having a specified average primary particle diameter and a specified compd. as an electrostatic charge controlling agent. SOLUTION: This developer contains a bonding resin, carbon black of pH2-5 having 20-50nm average primary particle diameter and a metal-contg. salicylic acid compd. represented by the formula as an electrostatic charge controlling agent. In the formula, M is a metallic atom of Zn, Fe, Ni or Co, preferably Zn and each of R1 and R2 is H or 1-6C alkyl.</p> |
