PROCESS FOR THE PREPARATION OF 4-AMINO-5-HYDOXY-1,7-NAPHTHALENE DISULFONIC ACID

摘要

The 4-amino- 5-hydroxy- 1,7-naphthalene disulfonic acid of formula (I) is prepared by reacting 100wt.pts. of a 1-naphthyl amine-4,6,8- trisulfonic acid with 180˜220wt.pts. of an alkali metal hydroxide i.e. sodium hydroxide or potassium hydroxide in the presence of 70˜90wt.% water at 135˜145deg. C for 3˜8hrs. The compound (I) is useful as an intermediate for the production of a red colouring reactive or acid dyestuff.