| abstract |
Crystalline, azopyrazolone acid dye and the preparation thereof, which dye is useful for dyeing textile materials using conventional, aqueous acid-dyeing techniques and is of the formula ##STR1## WHEREIN R is H or CH 3 , x is 1 or 2, y and z are each 0 or 1, the sum of y and z is 1 and M is lithium, sodium or potassium cation, said crystalline dye being characterized by the absence of absorption in the 6.0 micron region of its infrared scan. |