Easy open closure system
AssigneeMinnesota Mining and Manufacturing Company
InventorsShih-Lai Lu, Andrew H. Wong
Life of this patent
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Abstract
An end portion for a container having a preformed opening therein and an easy-open closure system therefor, the closure system comprising an exterior tape over the opening which is manually removable, the tape being adhered by an adhesive which comprises the reaction mixture of an aryl isocyanate, an aliphatic glycol, and a defined mixture of hydroxy terminated polyesters.
Claims12
In a container sealed by means of a tape closure, the improvement which comprises the use of a polyurethane adhesive to seal said closure, said polyurethane adhesive comprising the non-crystallizable reaction product of an aryl isocyanate, an aliphatic glycol, and a mixture of hydroxy terminated polyesters, said mixture of polyesters comprising a low molecular weight polyester, the molecular weight thereof being from about 750 to about 1,250 and a high molecular weight polyester, the molecular weight thereof being from about 1,700 to about 2,400, the ratio of said low molecular weight polyester to said high molecular weight polyester being from about 4:1 to about 0.25:1.
Dependencies are inferred from the claim text.