US Patent 7252870 Nonwovens having reduced Poisson ratio

Nonwoven materials having a pattern incorporated into the materials are disclosed. The nonwoven materials may be, for instance, tissue webs, meltspun webs such as meltblown webs or spunbond webs, bonded carded webs, hydroentangled webs, and the like. The pattern may be incorporated into the webs using various techniques. For instance, the pattern may be formed into the web by topically applying a bonding material. In an alternative embodiment, the pattern may be formed according to a thermal bonding process. The pattern contains individual cells that include two spaced apart expanded regions separated by a constricted region. By incorporating the pattern into the web, a material is produced having a relatively low Poisson ratio.