The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 14, 2001
Filed:
Aug. 16, 1999
Ulrich E Hess, Corvallis, OR (US);
Hewlett-Packard Company, Palo Alto, CA (US);
Abstract
A high efficiency thermal inkjet printhead. The printhead includes a substrate, a base layer on the substrate, and at least one ink expulsion resistor on the base layer. The base layer is made from a special material that experiences a substantial increase in thermal conductivity at the elevated temperatures associated with resistor operation. As a result, the base layer functions as an effective thermal insulator when the resistors are initially energized, yet allows heat to dissipate from the resistors immediately after the deactivation thereof. Numerous benefits are achieved by this development including (1) rapid resistor cool-down between successive ink ejection cycles (which improves the speed/operational frequency of the system); and (2) the prevention of undesired heat dissipation through the base layer when the resistors are initially energized, with the generated heat instead flowing into the ink.