Abstract: Disclosed is a chitosan-coated natural fiber, comprising 70-99.9% by weight of a core consisting of a natural fiber; and 0.1-30% by weight of a sheath layer consisting of chitosan, uniformly coated over the surface of the natural fiber core. The chitosan-coated natural fiber is prepared by pretreating a natural yarn to improve affinity for chitosan, coating the pretreated natural fiber with chitosan, and stabilizing the fiber by heating or with an alkaline solution. The chitosan-coated fiber is 5-10 &mgr;m in fineness and 1-300 mm in length and shows desirable fiber properties as well as beneficial functions of chitosan, including antibacterial, deodorization and hemostatic activities.

Abstract: Disclosed is a chitosan microflake which is exceptionally improved in coatability to the skin. The chitosan microflake is manufactured by dissolving chitosan in a weak acidic, aqueous organic acid solution to give a chitosan solution, extracting chitosan from the solution, and solidifying the solution and pulverizing the form film into the microflake which has a width ten fold greater than thickness. With high coatability onto the skin, the chitosan microflake improves the medicinal efficacies of highly pure chitosan, including wound healing, sterilization, prevention or suppression of cicatrix formation, and recuperation from wounds, upon being applied to external traumas such as dermal damages, surgically operated regions and burns. In addition to the medicine and medical industries, the chitosan microflakes can find numerous applications in a broad spectrum of industries, including food, bioengineering, cosmetic, agricultural, chemical engineering, and environmental industries.