Coextrudable Hot-Melt Adhesive
AssigneeHenkel AG & Co. KGaA
InventorsMarcus Heemann, Eckhard Pürkner, Volker Erb, Maja Schroeder, Dirk Vianden
Life of this patent
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Abstract
A hot-melt adhesive for resealable packaging, containing 30 to 90 wt. % of at least one copolymer based on ethylene and/or propylene together with C4 to C12-α-olefins, which is obtainable by metallocene-catalyzed polymerization, with a melt index of 5 to 100 g/10 min (DIN ISO 1133), 5 to 50 wt. % of tackifier resins with a softening point of 80 to 140° C., 0 to 15 wt. % of waxes with a melting point of 120 to 170° C., 0.1 to 20 wt. % of additives and auxiliaries, the adhesive having a viscosity of 25,000 mPa·s to 250,000 mPa·s, measured at a temperature of 170 to 190° C.
Claims18
) A hot-melt adhesive for resealable packaging comprising:
- a) 30 to 90 wt. % of at least one metallocene-catalyzed copolymer, based on an ethylene and/or propylene with C4 to C20-α-olefins, which has a melt index of 5 to 100 g/10 min at 190° C.;
- b) 5 to 50 wt. % of a tackifying resin, which has a softening point of 80 to 140° C.;
- c) 0.5 to 15 wt. % of a wax, which has a melting point of 120 to 170° C.;
- and
- d) 0.1 to 20 wt. % of an additive and/or auxiliary;
- and
- wherein the adhesive has a viscosity of 25,000 to 250,000 mPa·s at 170 to 190° C.
) The hot-melt adhesive of claim 1, further comprising 0.5 to 10 wt. % of a hydrogenated hydrocarbon resin with a softening point of 0 to 50° C.
) The hot-melt adhesive of claim 1, comprising up to 5 wt. % of the additive and the additive is selected from the group consisting of a UV stabilizer, pigment, adhesion promoter and mixtures thereof.
) The hot-melt adhesive of claim 1, further comprising 0.5 to 15 wt. % of polyisobutylene.
) The hot-melt adhesive of claim 1, wherein the adhesive is essentially free of a plasticizer.
) The hot-melt adhesive of claim 1, further comprising 0.5 to 10 wt. % of a polymer based on olefin and (meth)acrylic acid ester.
) The hot-melt adhesive of claim 7, wherein the polymer comprises anhydride or carboxyl groups.
) The hot-melt adhesive of claim 1, wherein the adhesive further comprises a rosin resin, a tall oil resin or a fully or partly hydrogenated hydrocarbon resin.
) The hot-melt adhesive of claim 1 comprising:
- a) 40 to 80 wt. % of the metallocene-catalyzed copolymer, based on ethylene and/or propylene with C4 to C12-α-olefins, which has a melt index of 5 to 40 g/10 min at 190° C.;
- b) 10 to 40 wt. % of the tackifying resin;
- c) 0.5 to 10 wt. % of the wax;
- and
- d) 0.1 to 20 wt. % of the additive and/or auxiliary.
) The hot-melt adhesive of claim 9, wherein the adhesive has a viscosity of from 30,000 to 150,000 mPa·s at 170 to 190° C.
) The hot-melt adhesive of claim 1, wherein the adhesive passes an EU Directive 82/711/EEC requirements.
) An article comprising the adhesive of claim 1.
) The article of claim 12 which is a multilayer film
) The article of claim 13 which is a foodstuffs packaging.
) The article for claim 12 comprising a polyolefin or polyethylene film.
) The article of claim 12 which is a resealable packaging.
) A method of making the article of claim 12 comprising blown film coextrusion.
) The method of claim 17 wherein the coextrusion occurs at a temperature greater than 170° C.