| 摘要 |
PURPOSE:To apply magnetic toner in an invariably stable, uniform and unevennessfree thin layer by making a development sleeve surface specifically uneven by a sand blast treatment. CONSTITUTION:In a development device which uses single-component magnetic toner, a nonmagnetic sleeve 2 has a stainless steel surface roughened to 2-50mum unevenness pitch (p) and 0.1-8mum surface roughness (d) by a sand blast treatment by using irregular abrasive grains (#320-800). Magnetic toner 10 is applied uniformly over the sleeve 2 from a hopper part 7a by a thickness restraining member 1a. When the sleeve surface is not roughened, the toner aggregates magnetically into lumps at a toner staying part of the upper part of a magnetic blade 1a and they project from the blade to cause irregularity of application. For the application of an alternating voltage to the sleeve, the surface roughness is preferably 0.1-4mum. |
