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US 4,081,485 AGranted
Hydroquinone-ketone molecular compound and process for purifying hydroquinone using said molecular compound
OwnerTsukasa Eguchiinventor
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Abstract
The present invention relates to a novel compound which is considered to be a hydroquinone-ketone molecular compound. The invention also pertains to the method of producing such molecular compounds from hydroquinone and ketone. When the molecular compound is decomposed in the presence of water or an aqueous medium, hydroquinone can be obtained which undergoes little or no coloring even if left standing in the air for a prolonged period of time.
Claims1
A process for purifying hydroquinone which comprises
- (a) adding at least an equimolar amount of acetone to hydroquinone and heating the resulting mixture to the boiling point of acetone, thereby forming a hydroquinone-acetone molecular compound,
- (b) adding said molecular compound to water,
- (c) acidifying the resulting aqueous medium solution with sulfuric acid to a pH of about 1 to 5, and
- (d) treating the acidic medium solution in the presence of sodium sulfite at a temperature of between the room temperature and the boiling point of the acidic medium solution, thereby recovering crystals of hydroquinone.
1 more element
Dependencies are inferred from the claim text.