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:
Oct. 31, 2000
Filed:
Jun. 03, 1997
John L Stoffel, San Diego, CA (US);
James P Shields, Corvallis, OR (US);
Mark S Hickman, Vancouver, WA (US);
Raymond J Adamic, Corvallis, OR (US);
Mark L Choy, Escondido, CA (US);
Hewlett-Packard Company, Palo Alto, CA (US);
Abstract
Described is a color inkjet printer for optimum bleed prevention in a printer utilizing multiple black and color pens wherein there is provided one print cartridge for dispensing black ink onto the printing medium and at least one print cartridge for dispensing color ink onto the printing medium. The cartridge for dispensing black ink contains an ink with little or no surface active agent while the cartridge for dispensing color ink contains a sufficient amount of surface active agent to reduce bleed between the colors. Moreover, the cartridge for dispensing black ink contains an ink which reacts with at least one and more preferably all inks contained in the cartridge for dispensing color ink. This reaction reduces bleed on images where the black print is adjacent to the color print to an acceptable level without requiring the black ink to contain surface active agents that would lead to inferior quality black text on the plain paper print medium. The reaction may be initiated by pH changes, reaction between the actual colorants, or reaction between one of the colorants and a component in the other ink.