Method for purifying {60 -amino-{68 -caprolactam

摘要

Purified alpha -amino- epsilon -caprolactam free from not only visible ray-absorbing substances but ultra-violet ray-absorbing substances, such as, tetrahydrophenazine and octahydrophenazine, and volatile basic substances such as, ammonium salts, is obtained by dissolving a crude alpha -amino- epsilon -caprolactam in a solvent consisting of at least one alkyl ester of saturated aliphatic acid of the formula: