Water dispersible polyurethane adhesive compositions and adhesive layer formed therefrom
AssigneeTextron Inc.
InventorsHelmut W. Kucera, Samy K. Saad
Life of this patent
Estimating the term…
Abstract
A method for forming a urethane adhesive layer from an aqueous system by mixing a first component comprising a water dispersible oligourethane having a plurality of ##STR1## groups with an organic water dispersible second component to initially form a relatively low molecular weight composition tacky at a temperature below about 90.degree. C. after removal of aqueous solvent followed by subsequent formation of a higher molecular weight composition, applying a layer of the resulting mixture to a substrate and removing the aqueous solvent from the layer to form an adhesive layer tacky at a temperature below 90.degree. C. The invention also includes the adhesive layer and the method for adhering surfaces using such a layer.
Claims9
A layer from which water has been removed comprising an incompletely reacted mixture of a first component comprising an oligourethane composition with a second component which can react with the first component;
- said first component comprising an oligourethane, said oligourethane comprising a polyurethane composition having an average molecular weight of less than about 15,000 and containing sufficient chemically bound hydrophilic groups selected from anionic groups, cationic groups, ethylene oxide residue and mixtures thereof to render the composition water dispersible, the molecules of said polyurethane composition comprising a plurality of amino groups or semicarbazide groups which have at least one ##STR5## group;
- and said second component comprising an organic compound dispersible in an aqueous solvent, the molecules of said organic compound containing a plurality of groups capable of reacting selectively with the amino or semicarbazide groups within the layer, said layer being tacky at a temperature below about 90.degree. C.
Dependencies are inferred from the claim text.