Laminated fibrous web comprising differentially bonded layers, and method and apparatus for making the same

摘要

A laminated fibrous web comprising: a first fibrous layer; and a second fibrous layer bonded to and of lower density than the first fibrous layer; wherein fibers in the second fibrous layer are less bonded to one another, than fibers in the first fibrous layer are bonded to one another; and wherein the first and second fibrous layers are less bonded to each other than fibers in the first fibrous layer are bonded to one another. Also disclosed are a method and apparatus for making such laminated fibrous webs, by the steps of forming a first fibrous layer of a first relatively higher density; bonding fibers of the first fibrous layer to one another at a first relatively higher extent of bonding; forming a second fibrous layer at a second relatively lower density; bonding fibers in the second fibrous layer to one another at a second relatively lower extent of bonding; and bonding the first and second fibrous layers to each other at a third relatively lower extent of bonding of fibers to one another in the first fibrous layer. Apparatus is also described for carrying out such method by sequential thermal pattern-bonding of the respective web layers.