| 摘要 |
PURPOSE:To enable fixing at a low temperature and improve an offset-printing resistance by specifying THF unsoluble amount of binder resin and GPC molecular amount distribution of THC soluble amount. CONSTITUTION:In a toner, magnetic powder including 0.05-10wt.% of silicon atoms is used, THF unsoluble amount of binder resin is less than 10wt.% with respect to binder resin, weight average molecular amount/average molecular amount is equal to or larger than 18 in GPC (gel pemeation chromatgraphy) of THF soluble amount. There are a peak value MA in the range of molecular amount 3000-200000, a minimum value MB in the range of 380000-1 million, a minimum value MC in the range of 20000-380000, and MB/MA= 30-150. When the areas of respective molecular amount distribution curves from molecular amount 400-Md and from Md to 5 millions are SA, SB, and the area surrounded by the line between the apexes MA, MB and the respective molecular amount distribution curves is Sd, the relation should be satisfied as expressed by the formula I. It is thus possible to perform fixing at low temperatures and improve offset-printing resistance in a wide range of temperatures. |
