Hewlett-packard Development Company, L.p.

Hp Indigo B.v.

Blair A Butler

David Sabo

M Derek Patton

Ali Emamjomeh

George Sarkisian

Geoffrey Schmid

Timothy J Carlin

James A Mott

James Huai Kiang

Paul Fishbein

Alexander N Govyadinov

Ronald Albert Askeland

John A Barinaga

Daniel D Dowell

Ronald J Ender

Craig L Malik

David S Vejtasa

Stanley J Kozmiski

Elizabeth Ann Visnyak

Andre Garcia

Jinsong Gao

Ziv Yosef

Si-Lam J Choy

Avinoam Halpern

Sean W Dobbins

Jeffrey Zampell

Sarah Ann Russell

Seth Stephen Haddix

Scott Sayer

Jorge Angel Borquez

A printing fluid pen includes a plurality of fluid ports, a pressure regulator in fluid communication with a first fluid port, and a valve in fluid communication with a second fluid port. The first fluid port is to deliver printing fluid to a fluid ejection device, and the second fluid port is to direct printing fluid out of the pen. In response to negative pressure, the valve is to open to enable fluids within the pen to exit via the second port.

Printing fluid circulation

Examples include an end cap system for a developer unit in a liquid photographic printer. The end cap system includes an end cap and a film that includes a first outermost superficial layer and a second outermost superficial layer opposed to the first outermost superficial layer. The first outermost superficial layer is a pressure sensitive adhesive layer applied to a portion of an inner surface of the end cap. The second outermost superficial layer is a low surface energy layer to be exposed to liquid photographic printing fluid during printing.

End caps and films

A roller charging device may include a Y-shaped electrically conductive brush and a screw terminal coupling the Y-shaped electrically conductive brush to a housing of the roller charging device and electrically coupling the Y-shaped electrically conductive brush to a power source. A printing fluid developer may include a plurality of rollers and a plurality of Y-shaped brushes to each contact one of the plurality of rollers wherein each of the Y-shaped brushes provides an electrical charge to each of the plurality of rollers.

Y-shaped brushes

A technique includes rotating a squeegee roller to regulate a film thickness of ink on a developer roller; and using the developer roller to transfer a portion of the ink from the developer roller to a photoconductive member. The technique includes creating, by an electrode, a potential bias with the developer roller to transfer the ink to the developer roller; and inhibiting flow streaks on the developer roller, where inhibiting the flow streaks includes restricting a flow of ink between the squeegee roller and the electrode.

Inhibiting ink flow streaks

A transmission for a developer unit that includes a developer roller to apply LEP ink to a photoconductor, a cleaner roller to clean the developer roller, and a squeegee roller to squeegee ink on the developer roller. In one example, the transmission includes a mechanical drive train to, with the cleaner roller, simultaneously drive the developer roller at a first surface speed and the squeegee roller at a second surface speed slower than the first surface speed.

Transmission for an LEP developer unit

Pre-treatment composition and printing method, for producing durable images, using it are disclosed. Said pre-treatment composition includes a liquid vehicle, a polyvalent metal salt as fixing agent, and a latex resin having a glass transition temperature (Tg) ranging from &#x2212;22&#xb0; C. to 20&#xb0; C. Said method encompasses applying the pre-treatment composition onto a recording medium and applying an ink composition including an aqueous liquid vehicle and a colorant, over said pre-treatment composition, wherein the time interval between the finishing point of the application of the pre-treatment composition and between the starting point of the application of the ink composition is between 1 and 30 seconds.

Printing method with pre-treatment composition

A printing system and method form one or more pretreatment compositions on a medium. The one or more pretreatment compositions are selected based upon a parameter of the medium.

Printing system

An ink cartridge has a first portion having a plurality of chambers formed therein; a second portion attached to the first portion and having at least one opening into each of the plurality of chambers, and wherein for each opening the second portion further includes at least a portion of a fluid directing channel; and a third portion attached to the second portion and configured to receive a plurality of fluids and direct each of the plurality of fluids into one of the respective fluid directing channels such that each of the plurality of fluids flows into a respective one of the plurality of chambers.

Ink cartridge with multiple chambers aligned along an axial length

Various embodiments of a wiper apparatus and method for cleaning a printhead are provided. In one embodiment, the wiper apparatus includes a wiper having a leading contact surface, a trailing contact surface, and a capillary passageway that extends at least partially along an axis that intersects the leading contact surface and the trailing contact surface.

Wiper apparatus and method for cleaning a printhead

In one embodiment, a filter element carrier comprises a first wedge shaped cavity, a second wedge shaped cavity isolated from and overlapping the first cavity, an outlet from a deep part of the first cavity, and an inlet to a deep part of the second cavity. In one embodiment, a filter element carrier comprises a body defining a cavity, the body having a first surface configured to support a first filter element covering one side of the cavity and a second surface configured to support a second filter element covering a second side of the cavity opposite the first side, and a barrier to fluid flow interposed between a first part of the cavity adjacent to the first surface and a second part of the cavity adjacent to the second surface.

Filter element carrier, filter, ink pen

A thermal ink jet printer having enhanced heat removal capability and method of assembling the printer. The thermal inkjet printer includes a thermal inkjet print bead adapted to hold an ink body therein. A heating element is adapted to be in fluid communication with the ink body for generating heat to heat the ink body. A vapor bubble forms in the ink body to eject an ink drop when the heating element causes the ink body to reach a predetermined temperature. Presence of the vapor bubble forces on ink drop out the printer to form an image on a recording medium. A conductive heat removal structure is in thermal communication with the heating element and is also in fluid communication with the ink body. Heat generated by the heating element is transferred from the heating element and into the heat removal structure. The heat removal structure then surrenders the heat to the ink body, which functions as an &ldquo;infinite&rdquo; heat sink. In this manner, the heat removal structure provides enhanced heat removal of heat generated by the heating element.

Growing community of inventors

San Diego, CA, United States of America

Blair A Butler