| 摘要 |
PURPOSE:To obtain a developer which is stable and uniform in the quantity of frictional electrostatic charging, is free from photographic fogs, and scattering and cohesion of the toner, increases the number of enduring copies and has a high transfer effect at high humidity by permitting fine silicate powder contg. alumina to be contained. CONSTITUTION:The fine silicate powder contg. alumina is contained in the developer. The fine silicate powder contg. alumina which is 0.1-20% contents of alumina, and 0.01-2mum average primary grain sizes is used, and it is preferable to add the same to the developer at 0.01-20wt%. For example, 100pts. polystyrene regin 5pts. carbon black and 5pts. methylene blue chloride are kneaded with hot rolls, after which the mixture is pulverized to 10-20mum average grain sizes. 100pts. ion powder of 50-80mum average grain sizes is added to 5pts. the mixture prepd. by adding 1.0wt% said fine silicate powder contd. alimina to the fine powder obtained in the way and mixing these with a Henschel mixer, whereby the electrophotographic developer is obtained. |
