反应详情

4,6-Diamino-1,3-benzenediol dihydrochloride (350 g, 1.64 moles) was dissolved in water (1650 ml) deaerated with nitrogen. Terephthalic acid (265 g, 1.60 moles) was dissolved in 1M aqueous sodium hydroxide solution (3200 ml) and deaerated with nitrogen. The aqueous 4,6-diamino-1,3-benzenediol dihydrochloride solution was dropwise added to the aqueous disodium terephthalate solution over 10 minutes to form a white precipitate of 4,6-diamino-1,3-benzenediol/terephtalate. The reaction temperature was maintained at 90° C. The obtained salt was filtered, dispersed in water [3 L (liter)] aerated with nitrogen and the dispersion was again subjected to filtration. This step of dispersing and filtering was repeated three times. The salt washed with water was suctioned on a filter in a nitrogen atmosphere, and the moisture was removed to about 20 wt %. The dehydrated salt was dried by reducing the pressure under the conditions of 1 Pa and 80° C.