ANTIBACTERIAL AGENT

PROBLEM TO BE SOLVED: To obtain an antibacterial agent capable of adding or coating on a raw material such as a resin, fibers, coating material, paper or a cosmetic and having excellent heat resistance or persistence of effects, etc., by using a specific metallic salt as an active component. SOLUTION: This antibacterial agent contains a metallic salt of polyasparagic acid (especially at least one kind selected from a group composed of silver, copper and zinc is preferable). Polyasparagic acid is obtained by, e.g., dehydrate- condensing asparagic acid using phosphoric acid as a catalyst to obtain a polysuccinimide, alkali-hydrolyzing the resultant polysuccinimide to obtain a polyasparagic acid salt, then isolating under an acidic condition. Moreover, a metallic salt is obtained from the resultant polyasparagic acid. A mixing amount of the antibacterial agent is about 0.01-30wt.%, preferably 0.05-20wt.% to the objective raw material. The antibacterial agent is mixed into, kneaded with or coated on the raw material at the above ratio to obtain various antibacterial materials. The antibacterial agent exhibits an antibacterial property to a bacterium such as Pseudomonas aeruginosa or Escherichia coli or a microorganism such as a mycotic fungus such as Penicillium notatum or Trichoderma fungus.