| 摘要 |
PROBLEM TO BE SOLVED: To form a satisfactory image by driving at low voltage by incorporating specified carbon black into a core material obtd. by adding a colorant, a releasing agent, an electric charge controlling agent, etc., to a bonding resin. SOLUTION: Carbon black 16b, wax 16c and an electric charge controlling agent 16d are added to a bonding resin 16a. They are kneaded, cooled and classified to form powder having negative chargeability as a core material and an additive 16e is properly added to the core material to produce the objective toner 16. The carbon black 16b has about 150-320ml/100g DBP oil absorption. The toner 16 is fed to a toner flow controlling means by a toner feeding means while being charged by friction with the toner flow controlling means, the flow of the fed toner is controlled by the toner flow controlling means and a toner image is formed on recording paper. |
