US Patent 8021591 Method and apparatus for incrementally stretching a web

A method and apparatus is provided which uses activation members for incrementally stretching a web at a low strain rate. The activation members include an activation belt and a single activation member wherein the activation belt and single activation member comprise a plurality of teeth and grooves that complement and engage one another at a depth of engagement in a deformation zone. The depth of engagement can be controlled to increase linearly over at least a portion of the deformation zone such that a web interposed between the activation belt and the single activation member in the deformation zone is incrementally stretched at a low rate of strain.