Patent ID: 8163824
Filing Date: 2012-04-24
Classification: C08L,C09J

Abstract:
1. A hot melt adhesive composition, comprising consisting essentially of a blend of the following components; (a) about 5 to about 40 weight percent of a styrene-butadiene-styrene block copolymer, said styrene-butadiene-styrene block copolymer is a substantially linear styrene-butadiene-styrene block copolymer having a styrene content of about 38% by weight to about 50% by weight and essentially zero percent diblock, and a melt flow index of about 3 g/10 min to about 11 g/10 min at 190° C. with a 5 kg weight, and a polydispersity of about 1.01 to about 1.30, and has a weight average molecular weight of 100,000 or higher; (b) about 2 to about 30 weight percent of an endblock resin wherein the end-block resin has a softening point of from 100 to 160° C.; (c) about 20 to about 70 weight percent of a tackifier; (d) about 0 to about 25 weight percent of a compatible non-functionalized block copolymer; (e) about 0 to about 30 weight percent of an oil; and (f) about 0 to about 4 weight percent of an antioxidant; wherein the tackifier is present in an amount greater than the block copolymer and wherein the components total 100% by weight of the composition so that the adhesive has a viscosity less than 10000 cP at 325° F., and a cold flow value equal to or greater than 70% at 49° C. after 48 hours.