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. 04, 1997
Filed:
Dec. 22, 1995
Toshimitsu Kawasumi, Osaka, JP;
Hiroshi Inoue, Osaka, JP;
Toshihiro Sawaki, Osaka, JP;
Keiko Nakamura, Osaka, JP;
Hiroyuki Fukui, Osaka, JP;
Yoshiko Yamaoka, Osaka, JP;
Sakura Color Products Corporation, Osaka, JP;
Abstract
An aqueous ink is provided which comprises a coloring agent, a water-soluble solvent and water, where the amount of gas dissolved therein is less than the amount of gas present at the situation level. Where the aqueous ink composition is used for a writing instrument of ink-free type having a confined ink chamber structure, the writing instrument rarely causes ink leakage and writing defects such as uneven ink density and skips in a drawn line, even if it is allowed to stand at a high temperature or to stand for a long time.