Carrier material for electrophotographic developer

Abstract

Abstract PURPOSE:To enlarge strength of films without nessecity of baking at high temp. and to reduce adherence or accumulation of toners powder onto a surface of carrier and to provide stable frictional electrification properties by covering a surface of nucleus particles of carriers with covering materials contg. specific block polymer including fluorine. CONSTITUTION:The carrier core materials are covered with polymers which are expressed by following formula and thus carriers having excellent endurance are obtained. In the formula expressed by R-[A-B-)I]n, A and B are polymer segments. The one is a copolymer segment having 45-90/5-50/0-35mol. ratio of CH2=CF2/CF2=CF-CF3 or pentafluoropropylene/tetrafluoroalkyl vinyl ether, or a copolymer segment having 15-75/0-85/0-85mol. ratio of perfluoroalkyl vinyl ether/CF2=CF2/CH2=CF2 and the mol.wt. of the segment is 30,000/120,000. The other is a copolymer etc. having 30-100/0-70mol. ratio of CH2=CF2/ CF2=CF2 and the mol.wt. of the segment is 30,000-10,000,000. The ratio of the both segments of the block copolymer is 10-95 of the former / 5-90 of the latter; n is number of the bonds of R.

Inventors

• 👤 Itsuo Ikeda

Bibliographic Details