Breathable non-asphaltic roofing underlayment
AssigneeBuilding Materials Investment Corporation
InventorsVinay Mehta, Awdhoot Vasant Kerkar
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Abstract
A non-asphaltic roofing underlayment that is breathable, water resistant and skid-resistant is disclosed. The non-asphaltic roofing underlayment includes a woven or non-woven substrate in which at least one surface thereof includes a breathable thermoplastic film disposed thereon. The breathable thermoplastic film imparts water-resistant to the substrate as well as maintains the breathability of the substrate.
Claims17
A non-asphaltic underlayment comprising:
- a glass fiber-based substrate in which a first surface thereof is directly adhered to a breathable thermoplastic film having a minimum thickness of 2 mils, the breathable thermoplastic film comprises a thermoplastic polyurethane blended with ethylene methacrylate polymer, wherein the ethylene methacrylate polymer acts as an adhesion improvement component that improves adhesion between the breathable thermoplastic film and the glass fiber-based substrate, said breathable thermoplastic film imparts water-resistance to the underlayment while maintaining breathability thereof, the breathable thermoplastic film having a minimum moisture vapor transmission rate of greater than about 3 perms.
A non-asphaltic underlayment comprising a substantially non-water-resistant polypropylene substrate in which at least a top surface thereof is directly adhered to a polyurethane based thermoplastic film, said polyurethane based thermoplastic film imparts water-resistance to the underlayment while maintaining breathability of the underlayment, the breathable thermoplastic film having a minimum moisture vapor transmission rate of 3 perms or greater the polyurethane based thermoplastic film being blended with about 40 to 60% ethylene methacrylate polymer to improve adhesion between the polyurethane based thermoplastic film and the substantially non-water-resistant polypropylene substrate.
A non-asphaltic underlayment comprising:
- a breathable thermoplastic film comprising a thermoplastic polyurethane blended with ethylene methacrylate polymer, the ethylene methacrylate polymer acting as an adhesion improvement component;
- and
- a substrate, the substrate having a thickness of about 6 to 60 mils, the substrate being air sprayed with more than two mils but less than 10 mils of the breathable thermoplastic film, wherein the breathable thermoplastic film imparts water-resistance to the underlayment while maintaining breathability thereof as defined in ASTM E96 standard.
Dependencies are inferred from the claim text.