| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain a toner having a small particle size in which a charge controlling agent is well dispersed in a binder resin or the like by dispersing the charge controlling agent to have a specified number average particle size or smaller. SOLUTION: This electrophotographic toner essentially consists of a binder resin, a pigment and a charge controlling agent. The main component of the monomer compsn. to constitute the binder resin is, for example, styrene. As for the pigment, carbon black can be used without any limitation such as a number average particle size. As for the charge controlling agent, for exampler a polymer compd. having polar functional groups such as carboxyl groups, or a resin-based charge controlling agent can be used. Especially, a metal-contg. pigment acts both as a pigment and a charge controlling agent. The charge controlling agent is dispersed in such a manner that the number average particle size of the agent is <=0.3μm. It is not preferable if the number average particle size is larger than 0.3μm, because electrification among the toner particles is made inhomogeneous, which causes problems for developing characteristics.</p> |
