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:
Nov. 08, 2011
Filed:
Jan. 07, 2010
Palitha Wickramanayake, Corvallis, OR (US);
Palitha Wickramanayake, Corvallis, OR (US);
Hewlett-Packard Development Company, L.P., Houston, TX (US);
Abstract
Ink-jet ink sets, pigment-based ink formulations, methods of printing, and methods of enhancing print quality, are disclosed. One exemplary ink-jet ink set, among others, includes a pigment-based ink formulation at a first pH, including: a pigment-based ink, and an amphoteric dispersant having an isoelectric point; and a second ink formulation at a second pH, wherein the first pH and the second pH are each selected from an acidic pH and a basic pH, wherein the first pH and the second pH are not the same, and wherein the amphoteric dispersant has a higher isoelectric point than the first pH when the dispersant is acidic, and a lower isoelectric point than the first pH when the dispersant is basic.