Stereo reticulated polymeric lace-like structure and process for making the same

Claim 1

A process for producing a stereo reticulated lace-like structure from a polymeric blend comprised of a polyurethane substantially free of cross-links, an acrylic polymer, a blowing agent and a lubricant which comprises melting said blend, passing said melted blend through an extrusion die to form a continuous film, passing said film through a zone wherein said film upon emergence from the extrusion die is subjected to the action of said blowing agent whereby said film is reticulated, quenching said reticulated film, drawing said reticulated film while in said zone to orient the same longitudinally and transversely, and removing said reticulated film from said zone to a windup zone, said polyurethane being one made by the reaction of (a) an essentially linear hydroxyl terminated polyester made by the reaction of a dicarboxylic acid having the formula HOOC--R--COOH wherein R is an alkylene radical containing 2 to 8 carbon atoms with a glycol having the formula HO(CH 2 ) x OH wherein x is a number from 4 to 8; (b) a free glycol containing from 4 to 10 carbon atoms; and (c) a diphenyl diisocyanate, and said acrylic polymer being one comprising in 100 weight parts of polymer from about 40 to 97 weight parts of a lower acrylic acid ester, from about 0 to 45 weight parts of a methacrylic acid ester, and from about 3 to 15 weight parts of an α,β-olefinically unsaturated carboxylic acid having a terminal CH 2 ═C< group and containing from 3 to 4 carbon atoms.