| 摘要 |
<P>PROBLEM TO BE SOLVED: To obtain an image of high quality by using a developer which is high in circularity and small in particle size, and also obtain an excellent image, which is high in quality, for a long period of time. <P>SOLUTION: A development device is provided with; a toner T1 which is accommodated in a development container F and whose volume average particle size is 4.0 μm or more and 6.2 μm or less and average circularity is 0.965 or more; and a toner T2 which is previously applied to the surfaces of a development roller 3 and feeding roller 5 in a state in which the development device D is not used. In this case, a relation between R1 and R2 satisfies an equation 1.0<R2/R1≤1.5, and a relation between H1 and H2 satisfies an equation 1.0<H2/H1≤2.0, wherein R1 represents a volume average particle size of the toner T1, R2 represents a volume average particle size of the toner T2, H1 represents a half value width of a volume particle size distribution of the toner T1, and H2 represents a half value width of a volume particle size distribution of the toner T2. <P>COPYRIGHT: (C)2009,JPO&INPIT |
