Patent attributes
A fire retardant, vapor impermeable coating composition is disclosed which is useful for protecting gypsum, wood, polyurethane, polystyrene, and other construction materials and surfaces, such as components for buildings. The composition does not require halogenated compounds and is considered environmentally friendly. The composition is provided in the form of a liquid-applicable aqueous latex comprising at least one latex polymer and an expandable graphite, optionally a hydrophobic thickener, and optionally other fire retardants such as metal hydroxides, wherein the polymer is selected such that the composition, when coated onto a substrate and allowed to dry, has a vapor permeability not exceeding one perm (5.70×10−8 g/Pa·s·m2 when tested according to ASTM E96B-10 at an average dry film thickness of 40 mils). The invention provides fire retardant air barrier layers for construction materials, such as polyurethane or polystyrene insulation beads or panels, as well as vapor impermeable laminates for construction applications.
