| 摘要 |
PROBLEM TO BE SOLVED: To form a high resolution and high definition image. SOLUTION: Relating to a developing device to which this method is applied, an elastic member 7 disposed in contact with or in the vicinity of a toner support 1 by way of a toner 8 is provided with a toner charging means 20 to apply bias voltage having the same polarity as the toner above discharge starting voltage. The toner contains a bonding resin, a colorant, a wax component and an oxycarboxylic acid. When the weight of the oxycarboxylic acid extracted from 1 g toner by methanol is represented by A (g) and the weight of the oxycarboxylic acid extracted from 1 g toner by a 0.1 mol/l aqueous sodium hydroxide solution is represented by B (g), the expressions 1.05<=A/B<=3.00 and 0.10×10-3<=B<=3.50×10-3 are satisfied. |
