US Patent 8377870 Antimicrobial aqueous solution and its preparation method

The antimicrobial aqueous solution of the present invention comprises an original undiluted aqueous solution containing: 25 μg/ml to 50 μg/ml of an amphipathic preservative comprising a monoglycerol monolaurate; and 12.5 μg/ml to 30 μg/ml of an ε-polylysine. In preparing the antimicrobial aqueous solution, dissolution of the amphipathic antimicrobial can be promoted by addition of a sucrose monolaurate and by heating to 35° C. to 60° C. This antimicrobial aqueous solution can be used effectively, even within a range of concentrations lower than concentrations to be typically used for amphipathic antimicrobials. It is possible to adopt a diglycerol monolaurate, instead of the monoglycerol monolaurate.