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. 14, 1995
Filed:
Feb. 23, 1994
Roger F Evans, Corvallis, OR (US);
Charles L Thierheimer, Jr, Corvallis, OR (US);
Norman E Pawlowski, Corvallis, OR (US);
Hewlett-Packard Company, Palo Alto, CA (US);
Abstract
A method is provided for enhancing and accelerating wetting of hydrophobic foams for use as ink reservoirs in ink-jet printer pens. First, the foam is placed in a prewet bath, having already been compressed to expel air. The prewet bath contains an aqueous solution with a low molecular weight alcohol additive, such as n-propanol, ranging in concentration from about 3 to 10 wt. %. Second, the foam is repeatedly compressed and allowed to expand while in the prewet bath, thereby promoting the foam's absorbance of prewetting solution and further improving foam wettability. Finally, the foam is removed from the prewet bath and is compressed to expel excess prewetting solution. The foam retains residual alcohol from the prewet bath that subsequently becomes a constituent of the ink stored in the foam. In addition to improving the wetting process for hydrophobic foam, the alcohol additive prevents orifice plugging within ink-jet pens by becoming a residual constituent of the ink and wetting pen parts through ink usage.