Reactive hot melt adhesive composition and method for use thereof

Claim 1

A reactive hot melt-type adhesive composition comprising (a) a reactive compound, (b) a thermoplastic resin and (c) a tackifier; wherein: a. the reactive compound is a urethane prepolymer having terminal isocyanate groups at both ends thereof and a viscosity higher than 300,000 cps at 25°C; resulting from the addition polymerization of at least one diisocyanate and at least one diol b. the thermoplastic resin is an ethylene-vinylacetate co-polymer or an ethylene-acrylic acid copolymer, or an ethyleneacrylate copolymer or an atactic polypropylene or a polyethyleneterephthalate linear polymer; and c. the tackifier is a hydrogenated abietic acid-type rosin or esters thereof having its double bonds removed by hydrogenation in whole or in part, or a terpene-phenol copolymer of a mono- or diterpene wherein the terpene has 10 carbon atoms and having a 1.0 to 3.0 molar ratio of terpene to phenol; said adhesive composition comprising 20 - 73 wt % of said urethane prepolymer (a), 2 - 25 wt % of said thermoplastic resin (b) and 25 - 55 wt % of said tackifier (c) said composition having a viscosity ranging from 9000 cp to 2000 cp in the temperature range of 100° - 130°C.