PROBLEM TO BE SOLVED: To provide an aqueous solution capable of providing an ink having good color tone as a black color ink, high print density, and excellent in suppressing bronze brightness on recording images when using various recorded materials.;SOLUTION: There is provided an aqueous solution containing a preservative agent, a specific azo compound or a salt thereof (for example the following compound or a salt thereof) of 1 mass% to 25 mass%.;COPYRIGHT: (C)2014,JPO&INPIT
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