Disclosed is a process for inhibiting the formation of discoloration in an aqueous composition selected from the group consisting of water-based paint, adhesive, caulk and sealant compositions, and combinations thereof, wherein said discoloration is caused by the presence of ferric ion or cupric ion together with pyrithione in said composition. The process comprises contacting the composition with a discoloration-inhibiting amount of a zinc compound selected from the group consisting of zinc salts of organic acids, zinc salts of inorganic acids, zinc hydroxide, zinc oxide, and combinations thereof. Also disclosed is an aqueous antimicrobial composition protected against discoloration attributable to the presence of ferric ion or cupric ion therein.
Disclosed is an aqueous coating composition comprising: (a) water, (b) a base medium, (c) a pyrithione salt, in an amount of from 0.01% to 2.0% based upon the weight of the composition, and (d) zinc oxide compound selected from the many grades suitable for paint manufacture at a concentration of from 0.001% to 10% based upon the weight of the coating composition. Also disclosed is an aqueous antimicrobial coating composition, characterized by antimildew efficacy and protected against discoloration attributable to the presence of pyrithione therein, said composition being selected from the group consisting of water-based paints, adhesives, caulks and sealants, and combinations thereof, said composition comprising water, a pyrithione salt or acid, an organic base medium and a zinc compound, said zinc ion being present in said composition in an amount of from 0.001% to 10% based upon the weight of the coating composition.
A composition for a slurry for manufacture of acoustical panels includes one or more fillers, one or more binders, water and zinc pyrithione. At least of the fillers and/or binders includes microbial nutrients in an amount of at least 1% based on the dry weight of the acoustical panel. In another embodiment of the invention, acoustical panels include a core having a plurality of opposing surfaces and being at least 1/8 inches thick. The core comprises the dried product of a slurry of fillers, binders and water. Zinc pyrithione is present in at least one of the core and a coating applied to at least one of the surfaces of the core.
The present invention relates to non-spherical and/or non-platelet pyrithione particles. Also disclosed is a method for producing non-spherical and/or non-platelet particles of pyrithione salts, comprising reacting pyrithione or a water-soluble salt of pyrithione and a water-soluble polyvalent metal salt in the presence of a dispersant at a temperature from about 20.degree. C. to about 60.degree. C. to produce non-spherical and/or non-platelet particles of pyrithione salts. The present invention further relates to particles made by the above methods and products, such as shampoos, soaps, and skin-care medicaments made using these particles.
A mold-resistant gypsum panel includes a core of an interlocking matrix of calcium sulfate dihydrate crystals, a facing material on at least one side of the panel and a salt of pyrithione dispersed through both the core and the facing materials. A method of making a mold-resistant gypsum product is also provided. A slurry of calcined gypsum, water and a water-soluble pyrithione salt is formed, then deposited on a sheet of facing material. The slurry on the facing material is shaped into a panel and maintained under conditions sufficient for the calcined gypsum to react with the water to form a core comprising an interlocking matrix of set gypsum crystals. Heating of the panel causes evaporation of the water that did not react with the calcined gypsum.
The present invention relates to non-spherical and/or non-platelet pyrithione particles. Also disclosed is a method for producing non-spherical and/or non-platelet particles of pyrithione salts, comprising reacting pyrithione acid or a water-soluble salt of pyrithione and a water-soluble polyvalent metal salt in the presence of an ionic surfactant composition at temperature from about 20.degree. C. to about 60.degree. C. and at a pH from 4-9 to produce non-spherical and/or non-platelet particles of pyrithione salts. The present invention further relates to particles made by the above methods and products, such as shampoos, soaps, and skin-care medicaments made using these particles.