Abstract: A refillable cartridge for inkjet printing devices having an ink supply off-board the cartridge carrier is characterized in that it is filled with an ink supply prior to shipment and the refill opening through which replenishment ink is supplied during printing is left open during shipment and storage. The interior of the cartridge is partitioned into a free ink reservoir, a foam-filled ink reservoir and an air buffer region. The foam-filled ink reservoir is filled with a foam material saturated with ink prior to shipment. A portion of the foam material extends into the air buffer region and is left dry. As long as the refill opening is not closed, ambient pressure is applied to the ink supply in the cartridge via the refill opening and the air buffer region. An ink passage permits ink flow in either direction between the free ink reservoir and the foam-filled ink reservoir. Either reservoir may be connected to ink capillaries in a conventional heater chip.

Abstract: Various methods and apparatus are disclosed for facilitating the loading, transportation, and modulation of toner particles on a print head, as well as the transfer of toner particles onto a print medium. These methods and apparatus relate to the optimization of various elements on the print head to improve the speed and control of toner particles on the print head, as well as to the alteration of the electric field in the vicinity of the end of the print head, and the transfer of toner particles vertically from the print head.