COOL ROOF COVERING AND ADHESIVE THEREFOR

摘要

A cool roof covering for forming the outepnost layer of a bituminous roof coating is provided, this cool roof covering comprising multiple heat-reflecting cap-sheets arranged in an adjacent, overlapping edge fashion and a heat-reflecting cap-sheet adhesive applied to overlapping portions of the cap-sheets for securing these cap-sheets to one another. The heat- reflecting cap-sheets exhibit a solar reflectance of at least 60% and a thermal emittance of at least 65. The heat-reflecting cap-sheet adhesive comprises a storage-stable, VOC-compliant mixture containing at least 10 wt.% of one or more weather-resistant organic resins dissolved in an organic solvent, the adhesive having a viscosity of 15,000 cps or less at 77° F (25° C) and exhibiting a lap shear strength of at least about 17 lbf/in when applied to a substrate and dried.