Method of forming dichromatic copy images
AssigneeMinolta Camera Kabushiki Kaisha
InventorsSusumu Tanaka, Kaoru Takebe
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Abstract
The invention disclosed concerns a method of forming dichromatic copy images. An electrostatic latent image having a first image portion and a second image portion is formed. The first image portion is developed by a first magnetic brush developing device using at least a magnetic toner of first color triboelectrically chargeable to a specific polarity. The second image portion is developed by a second magnetic brush developing device using a mixture of a magnetic carrier substantially not triboelectrically chargeable with the magnetic toner and a non-magnetic toner of a second color triboelectrically chargeable to a polarity opposite to that of the magnetic toner by contact with the magnetic carrier.
Claims6
A method of forming dichromatic copy images comprising a first step of forming an electrostatic latent image having a potential pattern to be developed in a first color and a potential pattern to be developed in a second color, a second step of developing said first color potential pattern by a first magnetic brush developing device using at least a magnetic toner of first color triboelectrically chargeable to a specific polarity, a third step of developing said second color potential pattern by a second magnetic brush developing device using a magnetic carrier substantially not triboelectrically chargeable with said magnetic toner and a toner of a second color triboelectrically chargeable to a polarity opposite to said magnetic toner by contact with the magnetic carrier, and a fourth step of transferring the developed image.
A method of forming dichromatic copy images comprising:
- a first step of forming an electrostatic latent image having at least three different levels of potentials with a first level representing a first image portion, a second level representing a second image portion and a third level between the first and second levels representing a background portion for the first and second image portions;
- a second step of developing said first image portion by a first magnetic brush developing means using a magnetic toner of a first color triboelectrically chargeable to a specific polarity;
- a third step of developing said second image portion by a second magnetic brush developing means using a magnetic carrier substantially not triboelectrically chargeable with said magnetic toner and a toner of a second color triboelectrically chargeable to a polarity opposite to that of the magnetic toner by contact with the magnetic carrier;
- and
- a fourth step of transferring the image developed by said second and third steps onto a copying paper.
Dependencies are inferred from the claim text.