ALEXANDRIA, Va., July 23 -- United States Patent no. 12,365,652, issued on July 22, was assigned to TORAY INDUSTRIES Inc. (Tokyo).
"Method for producing Epsilon-caprolactam" was invented by Daijiro Tsukamoto (Kanagawa, Japan), Kenji Kawamura (Kanagawa, Japan), Katsushige Yamada (Kanagawa, Japan), Masato Akahira (Aichi, Japan) and Daisuke Yamamoto (Aichi, Japan).
According to the abstract* released by the U.S. Patent & Trademark Office: "The present invention relates to a method of producing Epsilon-caprolactam, the method including the following steps (A) and (B): (A) a step of reacting 5-cyanovaleramide with hydrogen in an aqueous solvent in a presence of a hydrogenation catalyst to obtain a 5-cyanovaleramide hydrogenation reaction mixtu...