Patent ID: 8367184

Claim:
An integral structured film comprising: a substantially planar film portion having a first major surface, a second major surface, and an average film portion thickness; and a plurality of tubular projections extending from said substantially planar film portion, wherein one or more tubular projections comprise: (i) a hole extending from a first projection end above said first major surface into or through said substantially planar film portion, wherein said hole has a projection hole diameter in a range from 25.4 μm (1 mil) to 254 μm (10 mil), (ii) a projection sidewall surrounding at least a portion of said hole, said projection sidewall having an outer projection sidewall surface, an inner projection sidewall surface, and a projection sidewall thickness, and (iii) a projection length extending a distance from said first projection end to said first major surface, wherein a ratio of said projection length to said average film portion thickness is at least about 3.5, wherein the projection sidewall thickness of at least a portion of said one or more tubular projections is equal to or greater than the average film thickness, and wherein said structured film is free of post-film forming, projection-forming orientation.