| 摘要 |
PROBLEM TO BE SOLVED: To prevent toner from being welded on a toner thin layer forming blade when the toner thin layer forming blade made of silicone rubber is used while it is properly worn within the guaranteed number of copies and further to form a uniform toner thin layer on a developing roller by specifying the roundness of the toner. SOLUTION: The toner whose roundness is larger than 0.94 is used. Thus, the working part tip 103 of the blade 101 is properly worn so as to eliminate the welding of the toner on the tip 103, and the deformation of the tip 103 caused by excessive wear is prevented and the toner thin layer is normally and smoothly formed. It is proper to set the hardness (JIS K 6301(A type)) of the silicone rubber at the tip 103 within 75 to 85 deg.. When the hardness is lower than the set one, the degree of the deformation caused by the wear is large and the normal toner thin layer is hardly formed. On the other hand, when the hardness exceeds the range, shaving amount is so small that a black stripe or a white stripe is caused by the welding of the toner. |
