Hewlett-packard Company

E.i. Dupont De Nemours and Company

Leonard Slevin

Mark S Hickman

Ronald Albert Askeland

Keshava A Prasad

John L Stoffel, Jr

Clayton L Holstun

Frank Drogo

Michele E Shepard

John R Moffatt

Howard Matrick

Kai-Kong Iu

Loren E Johnson

William A Houle

Catherine B Hunt

John T Rich

Ink-jet inks and method of printing using the same are provided, the inks comprising at least one colorant and an aqueous vehicle, the vehicle comprising at least one anionic or nonionic surfactant, at least one alkoxylated polyhydroxy organic solvent, at least one water-miscible organic solvent; and optionally, at least one hydantoin compound, and optionally, at least one branched C.sub.2 -C.sub.7 alcohol. The inks enable production of near photographic images having little or no coalescence, excellent waterfastness, and reduced dry time, on a range of print media, in particular, photobase glossy paper.

Ink-jet inks and method for printing the same

A color ink-jet printer is provided, with one pen for dispensing black ink onto a print medium and at least one pen for dispensing color ink onto a print medium. The pen for dispensing black ink is adapted to jet droplets of black ink of a first volume and the pen(s) for dispensing color ink are adapted to jet droplets of color ink of a second volume, with the first volume being larger than the second volume. Such a color ink-jet printer provides both superior text quality of the black ink and does not require as much ink volume of the color ink(s) as previous ink-jet printers.

Printer with pen containing a low dot spread black ink and a high dot

A color ink-jet printer is provided, with one pen for dispensing black ink onto a print medium and at least one pen for dispensing color ink onto a print medium. The pen for dispensing black ink contains a pigment-based ink and the pen(s) for dispensing color ink contain a water-miscible dye-based ink. Such a color ink-jet printer provides both superior text quality (black ink) and relative ease of service (color inks), since the black ink is used more than the color inks and thus tends to require less spitting due to its frequency of use. On the other hand, since the color inks are used less, the utilization of water-miscible inks, which require less spitting than pigmented inks to keep the nozzle clear, also require less spitting even with relatively lower frequency of use.

Color ink-jet printer with pigment black and dye-based color inks

Aqueous ink compositions containing anti-curl agents substantially reduce or eliminate paper curl in plain-paper printed elements without adversely effecting storage stability, decap properties or print quality, and thus eliminate the need for expensive and bulky mechanical curl-arresting devices or special curl-resistant substrates. Printing the inks on plain-paper substrates is the sole step in a process for reducing paper curl in plain-paper printed elements.

Aqueous ink compositions containing anti-curl agents

Inks for printing on plain papers are provided for thermal ink-jet printers. The inks comprise a vehicle comprising about 5 to 20 wt % of a glycol or glycol ether and the balance water, about 1 to 6% of a dye, and about 0.1 to 1% of an alginate. The alginate increases the viscosity to increase the frequency of operation. Unexpectedly, good print quality associated with lower frequency of operation is retained at the higher frequency of operation.

Plain paper inks

Growing community of inventors

San Diego, CA, United States of America

Leonard Slevin