| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for refining crystalline aminophenols having excellent effect from a respect scarcely causing discoloring with time even when stored in the air. SOLUTION: The method for refining the crystalline aminophenols comprises a step for drying crystal at≤40°C until operation under reduced pressure is finished after filtering crystal obtained by crystallizing aminophenols and washing the crystal. Aminophenols obtained from a method comprising the following steps A to C are used as the aminophenols. The step (A): a step for reacting dihydric phenol with ammonia. The step (B): a step for carrying out crystallization operation of aminophenols using ethers as a solvent. The step (C): a step for filtering crystal of aminophenols after the step (B). COPYRIGHT: (C)2005,JPO&NCIPI
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