US Patent 7156937 Needling through carrier sheets to form loops

A loop fastener product is formed by needling a batt of fibers through a carrier sheet such as a plastic film, to form loops on the other side of the carrier sheet. A binder, such as a powder resin or plastic film, is placed over the fiber side of the product and fused to the carrier sheet to bond the fibers in place. In some cases the product is needled in only discrete areas, leaving other areas free of loops. The product may be formed into outer covers for disposable diapers. Fibers of one resin are readily combined with films and backings of other resins to produce particularly thin and low weight loop materials.