| abstract |
The invention provides a kind of aqueous solution, the described aqueous solution contains at least one azo-compound or its salt of (a) sanitas and (b) expression as middle in general formula (1); And there is (b) content of 1-25 quality %.(in general formula (1), G represents nitrogen-atoms or-C (Rn 2 )=.Rn 2 represent hydrogen atom, sulfo group, carboxyl, replacement or unsubstituted formamyl or cyano group.Xn 1 , Xn 2 , Xn 3 , Xn 4 , Xn 5 , Xn 6 and Xn 7 represent hydrogen atom or monovalent substituent independently of one another.Yn 2 , Yn 3 and Yn 4 represent hydrogen atom or monovalent substituent independently of one another.Yn 2 , Yn 3 and Yn 4 can be connected to each other to form ring.Yn 2 , Yn 3 and Yn 4 all do not represent hydrogen atom simultaneously.Each appearance of M represents hydrogen atom or unit price counter cation independently.) formula (1). |