| 摘要 |
PURPOSE:To give superior particle characteristics, superior transfer characteristics, superior triboelectrifiability characteristics, and superior development characteristics by specifying a practical sphericity in a substantially spherical range, number average particle diameter, change rates of number and volume average particle diameters, triboelectrifiability, and specific resistivity. CONSTITUTION:The toner to be used has a Wadell's practical sphericity of 0.95-1.00, and a number average particle diameter of 5-25mum is superior in fluidity and of approximately true spheres, and small in amts. of fine and coarse particles, and therefore, triboelectrication is made uniform, and an image free from fog, scattered small spots, etc., can be obtained. The change rate of particle diameter is controlled to a narrow particle diameter distribution, such as <=50% and <=45% in the cases of number and volume average particle diameters, respectively. It has a triboelectrified amt. of + or -2-5muC/g, and a specific resistivity of 10<11>-10<16>OMEGAcm. As a result, an image is improved, and transferability and development performance are also improved. Disclosure of fine magnetic particles to the surface of each toner particle is prevented by using fatty acid, its metal soap, oxidized wax, or metal wax, and desirable triboelectrifiability and specific resistivity can be retained. |
