Electrophotographic development apparatus

摘要

An electrophotographic development method and apparatus using two magnetic brushes for developing two-color images do not disturb or destroy a first developed image during a second development process, since a second magnetic brush contacts the surface of a latent electrostatic image bearing member more lightly than a first magnetic brush and the toner scraping force of the second magnetic brush is reduced in comparison with that of the second magnetic brush by setting the magnetic flux density on a second non-magnetic sleeve with an internally disposed magnet smaller than the magnetic flux density on a first magnetic sleeve, or by adjusting the distance between the second non-magnetic sleeve and the surface of the latent electrostatic image bearing member or by use of other methods. Further, by employing toners with different quantity of electric charge, high quality two-color images are obtained.