| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a two-component developer having a long life, generating no toner aggregates or causing no image defect such as so-called spots or white voids. SOLUTION: In the two-component developer comprising a toner and a magnetic carrier, the distribution of the particle size of the toner shows the following characteristics. (1) The weight average particle size ranges from 6.0 to 11.5μm, (2) particles having <=5μm particle size are included by <=15% in number, (3) toner particles having twice or larger diameter than the weight average particle size are included by <=5 wt.%, and (4) the number average particle diameters D25 and D75 representing 25% and 75% cumulative number distribution, respectively, satisfies the relation of 0.60<=D25/D75<=0.85. When the toner is sifted through a 500-mesh sieve, the circularity of the toner remaining on the mesh ranges from 0.93 to 0.97. Moreover, when 100 g of the toner is sifted through a 500-mesh sieve, the weight of the residue is <=10 mg.</p> |
