| 摘要 |
PROBLEM TO BE SOLVED: To reduce the amt. of a surfactant to be added and to ensure the stability of the quantity of electric charges almost independently of the environment, by allowing hydrophilic groups to exist on the surface of carbon black. SOLUTION: When a hydrophobic monomer, an ionic monomer, carbon black and a fixation improver are emulsion-polymerized and plural fine polymer particles are aggregated to produce the toner for developing an electrostatic image, hydrophilic groups are allowed to exist on the surface of the carbon black by adsorbing a hydrophilic group substd. org. compd. on the carbon black. The hydrophilic group of the org. compd. is an anionic functional group such as carboxyl, sulfone, phosphoric acid, hydroxyl or amine or a cationic functional group. The BET specific surface area of the toner is preferably regulated to 5-100 m<2> /g. |
