US Patent 9877876 Breathable structural web and breathable structural web-forming apparatus

A breathable structural web includes a layered structure having at least a layer of a non-woven material. The layered structure includes a base layer portion that has opposite first and second sides, a plurality of hollow protrusions that are disposed at the first side and that protrude and that are tapered from the base layer portion in a first direction, and a plurality of indented portions that are disposed at the second side, that extend from the base layer portion in a second direction opposite to the first direction, and that respectively define a plurality of recesses which open in the first direction. The hollow protrusions are scattered among the indented portions.