Patent ID: 8158158

Claim:
A biocidal composition consisting of composite particles, each of said composite particles consisting of a shell, a core, and a fatty acid wherein said core is selected from surface oxidized copper powder, cuprous oxide, copper hydroxide, and combinations thereof, said shell consists of a copper pyrithione formed by reaction of pyrithione acid or a water-soluble salt of pyrithione with copper from said core, and said fatty acid is selected from the group consisting of stearic acid, oleic acid, glycerol, and combinations thereof, wherein said core has a water solubility of no greater than about 10 ppm, wherein said core is present in said composition in an amount of from about 99 to about 60% by weight of the composition, and wherein said copper pyrithione shell is present in an amount of from about 1 to about 40% by weight of the composition.