| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for effectively decoloring 6-hydroxy-2-naphthoic acid. SOLUTION: The method for decoloring 6-hydroxy-2-naphthoic acid is a method for decoloring 6-hydroxy-2-naphthoic acid by decoloring treatment and comprises carrying out the decoloring treatment while maintaining a solution system of 6-hydroxy-2-naphthoic acid at pH≤6. Activated carbon treatment is preferable as the decoloring treatment. Roughly purified 6-hydroxy-2-naphthoic acid is subjected to decoloring treatment. A reaction mixture obtained by reaction using Kolbe Schmitt reaction or the roughly purified reaction mixture is used as the roughly purified 6-hydroxy-2-naphthoic acid. COPYRIGHT: (C)2004,JPO&NCIPI
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