| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an ink composition in which the generation of density unevenness and streak unevenness is controlled after the preservation of a long period of time, that excels in storage stability, and that excels in discharge accuracy, and further that can form an image with glossiness. <P>SOLUTION: The ink includes an azo compound shown by formula (1) in an aqueous medium, and further the ink composition includes a phosphonate compound. In the formula, A denotes a substituted or unsubstituted aryl group or a substituted or unsubstituted nitrogen-containing five-membered heterocyclic group; G denotes a nitrogen atom or -C(R<SB POS="POST">2</SB>)=; R<SB POS="POST">2</SB>denotes a hydrogen atom, a sulfo group, a carboxy group, a substituted or unsubstituted carbamoyl group or a cyano group; Y<SB POS="POST">2</SB>, Y<SB POS="POST">3</SB>and Y<SB POS="POST">4</SB>each independently denote a hydrogen atom or a monovalent substituent; Y<SB POS="POST">2</SB>, Y<SB POS="POST">3</SB>and Y<SB POS="POST">4</SB>may be combined together to form a ring; all of Y<SB POS="POST">2</SB>, Y<SB POS="POST">3</SB>and Y<SB POS="POST">4</SB>do not denote a hydrogen atom at the same time; and Ms each independently denote a hydrogen atom or a monovalent counter-cation. <P>COPYRIGHT: (C)2012,JPO&INPIT |
