Patent ID: 10202333

Abstract:
The present invention provides a method of producing an aqueous solution containing bis(Nε-lauroyl lysine)dicarboxylic acid diamide and/or a salt thereof, and having a pH of 9-11, which includes a first step of reacting Nε-lauroyl lysine and/or a salt thereof with dicarboxylic acid dichloride in a water solvent having a pH of 12-14 to form bis(Nε-lauroyl lysine)dicarboxylic acid diamide and/or a salt thereof, a second step of adjusting the aqueous solution obtained in the first step to pH 7.5-8.5, a third step of adding Nε-lauroyl lysine to the aqueous solution obtained in the second step and filtering the mixture, and a fourth step of adjusting the aqueous solution obtained in the third step to pH 9-11.