摘要 |
<p>A water-soluble monoazo dyestuff useful for dyeing or printing natural or synthetic material containing hydroxyls and nitrogen has the formula <IMAGE> or a tautomeric form thereof, wherein R1 is methyl, ethyl or 6-methyl-7-sulphobenzthiazol-2-yl, R2 is methyl, methoxy or ethoxy, R3 is methyl or ethyl, R4 and R5 may be the same or different and are hydrogen, methyl or ethyl, M is hydrogen, alkali metal or ammonium and n is 0 or 1.</p> |