Patent ID: 6969479

Claim:
A method of forming a structured surface on an article, the method comprising: providing a tool roll comprising a cylindrical base roll comprising first and second ends spaced apart along a longitudinal axis, a first wire comprising a plurality of first voids formed therein, the first wire being wound in helical coils around the base roll, wherein the plurality of first voids in the first wire form a plurality of first cavities, each cavity of the plurality of first cavities comprising an opening at an outer surface of the tool roll, wherein a distance between the first wire and a reference plane transverse to the longitudinal axis of the base roll sequentially increases and decreases at least once when moving in one direction about a circumference of the base roll; contacting a moldable material to the outer surface of the tool roll to form the structured surface using the outer surface of the tool roll, the moldable material at least partially filling at least some of the first cavities; and removing the structured surface from the outer surface of the tool roll, wherein the structured surface comprises a plurality of protrusions corresponding to the plurality of first cavities.