| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain fine particles excellent in durability, stability of charged state and heat resistance and added to a toner by emulsion-polymerizing a polymerizable vinyl monomer in an aq. medium and treating the resultant cationic emulsion with a specified org. compd. SOLUTION: A polymerizable vinyl monomer is emulsion-polymerized in an aq. medium in the presence of a water-soluble polymn. initiator without using an emulsifier to form a cationic emulsion. This emulsion is treated with an org. compd. having an anionic group and it is dehydrated and dried to produce the objective positive charge type fine particles. The org. compd. is preferably a compd. represented by the formula [where X is a condensed polycyclic hydro-carbon group which may have a substituent, (n) is an integer of 1-5, R is hydroxyl, sulfonic acid, etc., and at least one of R's is a metallic salt]. The compd. represented by the formula is preferably a monovalent metallic salt of 10-camphor sulfonic acid.</p> |
