Patent ID: 7018492

Claim:
In a process for manufacture of tufted carpets comprising steps that comprise adhering to a stitched side of a tufted primary backing a plurality of stitches of face yarn comprising a plurality of filaments by applying a thermoplastic binder comprising a softened or melted thermoplastic resin into contact with the stitched side by (a) extruding the binder with melted thermoplastic resin into contact with the stitched side or (b) heating the binder applied or present in solid form in contact with the stitched side to soften or melt the thermoplastic resin, and cooling the thermoplastic binder in contact with the stitched side to solidify the resin, the improvement wherein the thermoplastic binder consists entirely or essentially of a thermoplastic polyethylene having flow properties corresponding to an MI of about 2.2 to about 105 g/10 min. as measured in accordance with ASTM D 1238; and a viscosity between approximately 230,000 and 4,881,000 cps at about 270° F. with a shear rate of about 10 sec −1 as measured in accordance with ASTM D 3835, and comprising steps that comprise applying to a plurality of the stitches, before the resin solidifies, a stitch bind composition having a viscosity effective for coating or penetrating the stitches to contact the filaments thereof ranging from about 0.5 to 2900 cps and comprising an aqueous liquid component that boils or vaporizes at a temperature such that it can be removed by heating below a temperature at which the tufted backing is damaged by heat and an organic polymer component that bonds filaments of the stitches on removal of the aqueous liquid component, wherein the stitch bind composition is applied in an amount effective to provide about 0.2 to about 3 ounces of the organic polymer component or a residue thereof per square yard of the stitched side; and, after applying the stitch bind composition but before the resin solidifies, heating the stitch bind composition to substantially remove the aqueous liquid component without damaging the tufted backing.