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:
Mar. 18, 2003
Filed:
Feb. 12, 2001
Shirley Lee, Poway, CA (US);
Joe R. Pietrzyk, late of San Diego, CA (US);
Hewlett-Packard Company, Palo Alto, CA (US);
Abstract
Ink-jet printer inks wherein kogation reduction is accomplished by the addition of phosphonate additives to the inks. In a preferred embodiment, the following are utilized: sodium salt of amino tri(methylene-phosphonic acid), 1-Hydroxyethylidene-1,1,-diphosphonic acid, diethylene triaminepenta(methylenephosonic acid); and potassium salt form of hexamethylenediamine tetra(methylene phosphonic acid). Although in the examples disclosed herein, the salt form of the phosphonic acids were used, the acid form of the phosphonic acid can also be used provided the pH of the final inks are adjusted to desirable levels. Use of the above listed additives essentially eliminate kogation for the life of the pens, such as those used in Hewlett-Packard Company's thermal inkjet printers.