| 摘要 |
<p>A blue acid anthraquinone dyestuff of the formula <FORM:1087710/C4-C5/1> is made by esterifying at an elevated temperature with amidosulphonic acid in the presence of an inert organic solvent a compound of the formula <FORM:1087710/C4-C5/2> The esterification is advantageously effected at temperatures above 60 DEG C., and preferably within the range 75 DEG to 105 DEG C. The starting material (II) may be made by condensation of 3 - amino - 4 - methoxyphenyl - 1 - b - hydroxy-ethylsulphone with 1 - amino - 4 - bromoanthra-quinone-2-sulphonic acid.</p> |
