... 4 5-hydroxy-2-hydroxymethyl-1,4-pyrone, used in cosmetics raw materials, agriculture, food additives Basic information:Kojic acidChemical ... Cosmetics: Kojic acid, (5-hydroxy-2-hydroxymethyl-1,4-pyrone, CAS: 501-30-4) is used for macula-removing and whitening.In ... into the lotion, face mask, liquid cream and skin cream. Whitening cosmetics containing kojic acid are able to treat effectively the freckle ...