| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a one-component developing type image forming method using toner maintaining good charging build-up performance in high-speed image formation, a developing device, a process cartridge and an image forming apparatus. <P>SOLUTION: The toner made of a toner base containing a resin, a color material, a charge controlling agent and a mold release material, and an externally additive agent is used as a one-component developing agent. Development is performed by a developing means including a developing roller, a supply member and a regulating member. The toner is made by adding the externally additive agent to the toner base obtained by fusing and mixing with an open-roll type mixer. The mold release material dispersed particle diameter WA (μm) and charge controlling agent surface exposing quantity CA (%), and the average charging quantities Q<SB>1</SB>(toner charging quantity after one cycle of the developing roller), and Q<SB>6</SB>(toner charging quantity after five cycles of the developing roller) of the toner satisfy: [0.1≤WA≤0.6 (1)], [0.1×WA+0.14≤CA≤0.1×WA+0.29 (2)], [¾Q<SB>1</SB>-Q<SB>6</SB>¾≤20 (3)], [Q<SB>6</SB>≥-30 (4)]. <P>COPYRIGHT: (C)2010,JPO&INPIT |
