Patent ID: 6946203

Claim:
A thermoplastic structure comprising: a) a low density core layer comprising polypropylene, highly crystalline polypropylene or high density polyethylene, said core layer having a density in the range of from 0.1 to 0.7 grams per cubic centimeters; b) a top outer layer comprising highly crystalline polypropylene or high density polyethylene, said top outer layer being exterior to, and on a first side of, said core layer; and c) a bottom outer layer comprising highly crystalline polypropylene or high density polyethylene, said bottom outer layer being exterior to, and on a side of, said core layer; wherein the thickness of said core layer is about 60 to about 95% of the overall thickness of said structure; wherein said structure is biaxially oriented; and wherein the stiffness of said structure in the machine direction is in a range from about 0.015 to about 0.15 pound force-centimeters.