HIGH QUALITY epsi-CAPROLACTAM AND MANUFACTURE OF THE SAME

摘要

PROBLEM TO BE SOLVED: To provideε-caprolactam having extremely high Pz which is an index of the amount of impurities included in theε-caprolactam, useful for raw material or the like of a polyamide resin. SOLUTION: Thisε-caprolactam includes less than 25 ppm of impurities observed by the following method. The high purityε-caprolactam is manufactured by adjusting the purification condition of theε-caprolactam according to the monitored amount of the impurities. (Measuring method)ε-caprolactam is selectively fractionated by injectingε-caprolactam to the first column (a fused silica capillary column using polyethyleneglycol 20M bonded with 2- nitroterephthalic acid as the stationary phase), fractionating the effusing components including the subject components of the just before the effusion of theε-caprolactam. The fractionated component is injected to the second column (a fused silica capillary column using 5% phenylmethylsilicone as the stationary phase), fractionated and the subject component is detected by a FID detector.