Patent ID: 7678443

Claim:
A multi-layer article comprising: a first layer comprising: a first backing, the backing comprising a first major surface and a second major surface, wherein the first major surface comprises a microstructured surface comprising depressed microstructured elements, wherein the microstructured elements have walls separating the microstructured elements and at least one wall has variable height along the wall and a maximum height and a minimum height along the wall, and wherein said microstructured surface comprises polyolefin microstructured elements, wherein each microstructured element shares one or more walls with each adjacent microstructured element; a first adhesive layer on the second major surface of the first backing; and a second layer comprising: a second backing, the backing comprising a first major surface and a second major surface, wherein the first major surface comprises a microstructured surface comprising depressed microstructured elements, wherein the microstructured elements have walls separating the microstructured elements and at least one wall has variable height along the wall and a maximum height and a minimum height along the wall, and wherein said microstructured surface comprises polyolefin microstructured elements; and a second adhesive layer on the second major surface of the second backing, wherein the first adhesive layer is in contact with the first major surface of the second backing, and wherein the first adhesive layer does not contact the first major surface of the second backing in locations along the walls where the wall has the minimum height.