Abstract: A microchannel fluidic device, such as an ink jet printhead, includes an fluid reservoir for receiving ink or other fluid from a supply. The reservoir has an inlet in communication with the supply, and an outlet. A plurality of nozzles are in fluid communication with the reservoir for delivering ink or fluid from the reservoir. The outlet of the reservoir is constructed and arranged such that air bubbles in the reservoir are ejected by differential pressure between the inlet and outlet, rather than being forced through nozzles. An overflow reservoir captures fluid ejected from the outlet during priming operations thereby to reduce waste, to enable treatment of the fluid, and/or to recirculate the fluid.

Abstract: A printhead uses large and small drop ejectors to achieve efficient gray scale printing. The printhead is arranged with a close packed configuration of alternating large and small nozzles positioned to maximize coverage while minimizing the volume of ejected ink. The printhead may be operated in a single pass mode or dual pass mode. In the single pass mode, complete coverage is effected by rippling through the odd numbered jets first and then rippling through the even numbered jets. The position of the small spots from the even numbered jets can be adjusted to maximize coverage and counteract offset between nozzle centers. Printheads with different size nozzles can also be operated by a staggered firing method using dual passes to offset spots in the scan direction by shifting the printhead between passes or alternating between groups of large and small nozzles.

Abstract: A printhead uses large and small drop ejectors to achieve efficient gray scale printing. The printhead is arranged with a close packed configuration of alternating large and small nozzles positioned to maximize coverage while minimizing the volume of ejected ink. The printhead may be operated in a single pass mode or dual pass mode. In the single pass mode, complete coverage is effected by rippling through the odd numbered jets first and then rippling through the even numbered jets. The position of the small spots from the even numbered jets can be adjusted to maximize coverage and counteract offset between nozzle centers. Printheads with different size nozzles can also be operated by a staggered firing method using dual passes to offset spots in the scan direction by shifting the printhead between passes or alternating between groups of large and small nozzles.

Abstract: An ink jet channel wafer for an ink jet printer has a first surface in which a plurality of anisotropically etched ink channels and an anisotropically etched ink reservoir are directly connected to one another. The ink jet channel wafer is etched using an admixture of at least one alkali metal hydroxide and at least one alcohol compound.

Abstract: An ink jet ink includes a colorant and a liquid component containing at least one of an epoxy and a vinyl ether. Water may also be dissolved in the liquid component. Preferably, the vinyl ether is ethylene glycol monovinyl ether. An ink jet recording process includes the steps of ejecting an ink jet ink, such as the inks of the present invention, from an orifice to form an image on a recording medium.