Patent ID: 6162288
Filing Date: 2000-12-19
Classification: C04B,C09K,Y02W

Abstract:
A fireproofing composition for a spray-applicable fireproofing slurry using a mixer, pump, hose, and spray-nozzle, said fireproofing composition comprising:a gypsum binder in the amount of 25-95% based on total dry solids in the fireproofing composition;at least one lightweight aggregate having a bulk density of 0.4-10 pounds per cubic foot, said at least one lightweight aggregate comprising expanded vermiculite, expanded perlite, expanded clay prills, glass beads, mineral wool, shredded paper, shredded expanded polystyrene, or mixture thereof, said at least one lightweight aggregate being present in an amount of 1-80% based on dry weight of solids in the fireproofing composition;an air entraining agent operative to entrain air of a stable nature in the composition when water is added to form a slurry to allow the composition to be pumped through hoses;a synthetic set retarding agent present in the fireproofing composition in an amount operative, when the fireproofing composition is made into a spray-applicable slurry and pumped through the hose and spray-nozzle at spray application temperatures of 35.degree.-150.degree. F., to delay setting of the fireproofing composition for at least 24 hours, said synthetic set retarding agent comprising polyacrylic acid or a salt or derivative thereof in the amount of 0.1-4.5% or a phosphoric acid or salt or derivative thereof in the amount of 0.2-9.0%, all percentages based on dry weight of said binder in the fireproofing composition, and said synthetic set retarding agent having a molecular weight between 1000-15,000.