Electrophotographic developing apparatus

An electrophotographic image developing apparatus comprising:

• a supply of toner;
• an electrostatic latent image holding member having an endless outer photosensitive layer disposed in electrical contact with a grounded inner conductive member, said photosensitive layer being formed at least partially of particles having a high affinity for one type of charge and adapted for forming a latent image in response to selective exposure to light and for movement past a development region, and said grounded inner conductive member being adapted to maintain a preselected charge level in said photosensitive layer;
• a toner holding member including an endless transfer surface, wherein said toner holding member is adapted to attract and hold a substantially continuous layer of said toner having a first specific charge on said transfer surface at said supply, and to move said layer of said toner to said development region in close or touching relation to said photosensitive layer of said electrostatic latent image holding member;
• and,
• charge adjustment means for decreasing said first specific charge of the toner on said transfer surface to a second, lower, specific charge as, or substantially immediately before, said layer of toner is delivered to said development region by said toner holding member;
• whereby toner having said first specific charge is transferred from said supply to, or substantially immediately adjacent to, said development region, and a latent image formed on said latent image holding member is visualized in said development region using toner having said second specific charge.

An electrophotgraphic apparatus comprising:

• a grounded electrostatic latent image holding member for receiving and holding an electrophotographic latent image thereon;
• and
• a toner holding member for electrostatically attracting toner to rotate and rendering the electrostatic image visible with the toner;
• wherein a surface of the electrostatic latent image holding member has the same polarity as the charging polarity of the toner by virtue of being formed of a material having a greater affinity for the polarity of charge than the toner such that the electrostatic latent image holding member tends to remove excess charge from the toner when the surface comes into contact with the toner and to thereafter dissipate the excess charge so removed.

An electrophotographic apparatus comprising:

• an electrostatic latent image holding member composed of an inner, grounded, translucent conductive member and an outer photoconductive layer, said inner and outer layers being formed in this order and in direct electrical contact with one another on a light-transmitting base,
• said photoconductive layer having the same polarity as a charging polarity of a toner, and having a greater affinity for that polarity than the toner;
• the electrostatic latent image holding member being adapted to rotate in a preselected direction;
• charging means for charging the electrostatic latent image holding member;
• exposing means for forming an electrostatic latent image by exposing in an exposing region the photoconductive layer from the base side downstream of the charging means in the direction of rotation of said electrostatic latent image holding member;
• and
• a toner holding member for electrostatically attracting the toner to rotate and rendering the electrostatic latent image visible with the toner at least in the exposure region or over the exposure region and a region located downstream thereof across the boundary therebetween.