Method and apparatus to optimize the transfer of developer fluid in an electrophoretic printing apparatus

An electrophoretic printing apparatus, comprising:

• an intermediate image carrier having an exposure head to create charge images on the intermediate image carrier, and a developer station with developer fluid having toner embedded in a carrier fluid, said developer station inking the charge images on the intermediate image carrier, and a transfer printing zone where the inked toner images are transferred to a printing substrate;
• the toner embedded in the carrier fluid being transported from the developer station to the intermediate image carrier in a first transport path segment and from the intermediate image carrier to the printing substrate in a second transport path segment;
• a temperature acting on the carrier fluid in the first transport path segment being above a melting point of the carrier fluid;
• and
• a temperature acting on the carrier fluid at the transfer printing zone being below the melting point of the carrier fluid.

A method to optimize transfer of a developer fluid having toner embedded in a carrier fluid in an electrophoretic printing apparatus, comprising the steps of:

• generating charge images of print images to be printed on an intermediate image carrier with an exposure head, the print images being inked into toner images by a developer station with the developer fluid, and transfer-printing the toner images onto a printing substrate in a transfer printing zone;
• providing a temperature for the carrier fluid where it transfers onto the intermediate image carrier so that the carrier fluid has a relatively low viscosity resulting in a relatively high mobility of the toner in the carrier fluid for substantially complete deposition in image areas;
• and
• providing a temperature for the carrier fluid at the transfer printing zone so that the carrier fluid has a relatively high viscosity so that an amount of carrier fluid drawn into the substrate is reduced.

An electrophoretic printing apparatus, comprising:

• an intermediate image carrier having an exposure head to create charge images on the intermediate image carrier, and a developer station with developer fluid having toner embedded in a carrier fluid, said developer station inking the charge images on the intermediate image carrier, and a transfer printing zone where the inked toner images are transferred to a printing substrate;
• a temperature for the carrier fluid where it transfers onto the intermediate image carrier such that the carrier fluid has a relatively low viscosity resulting in a relatively high mobility of the toner in the carrier fluid for substantially complete deposition in image areas;
• and
• a temperature for the carrier fluid at the transfer printing zone such that the carrier fluid has a relatively high viscosity so an amount of carrier fluid drawn into the substrate is reduced.