Title:
LACTAM AND ITS PURIFICATION
Document Type and Number:
Japanese Patent JP3298372
Kind Code:
B2
Abstract:
PURPOSE: To obtain in high purity a lactam as a raw material for synthesis or an industrial raw material for polyamide fibers, etc., by irradiating a lactam containing ultraviolet-absorbing impurities with ultraviolet rays to decompose the impurities.
CONSTITUTION: The objective high purity lactam is obtained by irradiating a lactam containing ultraviolet-absorbing impurities such as octahydrophenazine with ultraviolet rays having wavelengths of 280-350nm using pref. an artificial or natural light source pref. at an energy of ≥10m in the distance from the light source to the lactam to effect decomposition of the impurities. It is preferable that the lactam has an ultraviolet transmissivity at a wavelength of 290nm of ≥95% in the form of a 50% aqueous solution and be ε-caprolactam or ω- laurolactam. The lactam is pref. irradiated with ultraviolet rays in a molten state or a solvent solution (the solvent has a UVB-transmissivity ≥50%).
Inventors:
Ayako Kanai
Takashi Ohkubo
Kiyoshi Kanehara
Takashi Ohkubo
Kiyoshi Kanehara
Application Number:
JP19952295A
Publication Date:
July 02, 2002
Filing Date:
August 04, 1995
Export Citation:
Assignee:
Toray Industries, Inc.
International Classes:
C07D201/16; C07B63/02; (IPC1-7): C07D201/16; C07B63/02
Other References:
【文献】英国特許1309782(GB,B)