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:
Sep. 19, 2000
Filed:
Feb. 19, 1999
Akiko Bannai, Tokyo, JP;
Akio Kojima, Tokyo, JP;
Kiyofumi Nagai, Tokyo, JP;
Masato Igarashi, Kanagawa, JP;
Masayuki Koyano, Kanagawa, JP;
Hiroyuki Mochizuki, Tokyo, JP;
Takanori Tsuyuki, Shizuoka, JP;
Ikuko Tanaka, Tokyo, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
A set of color ink compositions for ink-jet printing includes yellow, magenta and cyan ink composition, each of which having water, a water-soluble coloring agent, a wetting agent, a surfactant and an antiseptic and mildewproofing agent, and the yellow ink composition has the lightness index L* of 95.+-.5 and the chromaticness indices a* and b* of respectively -6.+-.5 and 23 .+-.12, the magenta ink composition has the lightness index L* of 75.+-.5 and the chromaticness indices a* and b* of respectively 55.+-.25 and -28.+-.10, and the cyan ink composition has the lightness index L* of 87.+-.5 and the chromaticness indices a* and b* of respectively -35.+-.10 and -19.+-.8. Further, color ink images are formed on a recording material with a Stockigt sizing degree of 10 sec or more using the above set of color ink compositions and a printing head with a plurality of ink-ejecting orifices by performing dot printing on the recording material by ejecting the ink compositions from the ink-ejecting orifices with the printing head scanned over the recording material a plurality of times.