Hewlett-packard Company

Hewlett-packard Development Company, L.p.

Hewlett-packard Development, L.p.

Rama Prasad

Todd A Cleland

Dale R Oughton

Robert C Maze

Joseph M Torgerson

Storrs Townsend Hoen

Leslie Ann Field

Phillip W Barth

Michael D Miller

Robert N K Browning

Michael B Hager

Kenneth D Saul

Douglas M Collins

Several improvements have been made in inkjet print cartridges to realize 5 ng drop weights at ejection frequencies of 18 KHz. These improvements include small nozzle openings, improved heater resistor efficiency, and better ink supply reliability.

High print quality inkjet printhead

A fluid ejection device includes a substrate, drop generators formed on the substrate at a high density, primitive select lines, and a ground line. The drop generators are arranged in primitives of drop generators. Each drop generator includes a heater resistor having a high resistance. Each primitive select line is separately electrically coupled to a corresponding one of the primitives and is configured to connect to a power source. The ground line is electrically coupled to all of the primitives.

High quality fluid ejection device

A high quality inkjet printhead includes a substrate having a multiplicity of heater resistors formed thereon at a density of at least six heater resistors per square millimeter. Each of the heater resistors also has a total resistance of at least 70 &OHgr; and an overlaying passivation thermal barrier characteristic adjusted to enable ejection of an ink drop of less than 6.5 ng with an energy impulse equal to or less than 1.4 &mgr;joules.

High print quality printhead

This present invention is embodied in a low-cost printing system including a printhead and an ink composition that provides photographic-quality resolution. The printhead of the present invention includes a high-density array of drop generators that eject ink drops having a low drop weight and that operate at a high frequency. Further, high-resistance firing resistors are used to provide minimum energy dissipation and the firing resistors are preferably thin-film resistors to ensure that a minimal amount of energy is needed to eject ink drops. The stability of the ink drop volume is maintained by including an overdamped structure within the ink drop generators that allow the ink chambers to fill up with ink slowly. The ink composition of the present invention includes an ink additive that prevents decel from occurring during sustained high-frequency printing bursts.

High thermal efficiency ink jet printhead

For an inkjet printing apparatus having a large number of ink ejectors, it is desirable to have as few as possible interconnections to the ink ejectors. Sharing electrical ground returns between related ink ejector primitive groups with spaced apart terminals provides a reduction in interconnections while offering redundancy in the interconnection.

Shared multiple terminal ground returns for an inkjet printhead

A thermal inkjet printing apparatus employs a segmented heater resistor, a thin passivation layer, and a lower heater resistor activation energy to realize a high density drop generator printhead.

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Albany, OR, United States of America

Rama Prasad