US Patent 7459205 Reinforcing net

A reinforcing net for use in a reinforcing layer is formed by spacing two parallel spreader yarns under tension and wrapping weft yarns around the two spreader yarns. The reinforcing net can either be affixed to an adhesive coated substrate or coated with adhesive at the intersections of the yarns to bond the net together. The net may be affixed to a plurality of substrates to form a laminate. The net, a ribbon of net with one substrate, and the laminate, may be used in making and reinforcing spirally wound products such as ducts, duct insulation and the like. A number of warp yarns can be included in the reinforcing net to increase its strength. The method of manufacturing the reinforcing net includes the steps of creating tension in the spreader yarns, providing a least one spool for supplying weft yarn, longitudinally advancing the spreader yarns, rotating the spool around the advancing spreader yarns and applying adhesive to the intersections of the yarns.