Isothiazolone in contact with the micro-organisms that can rapidly and irreversibly inhibit its growth, resulting in the growth of micro-cells, the common fungi of the new army, algae has a strong role in the suppression and killing. Killing rate, degradability, and has not longevity residue, safe operation, compatibility, and stability, the use of low cost. This product is widely used in petroleum, paper, pesticide, cutting oil, leather, ink, dye, leather and other industries.