Patent ID: 7455802
Filing Date: 2008-11-25
Classification: B29C,B29L,G03G

Abstract:
1. A stress/strain relief process for a flexible, multilayered web stock comprising: providing a multilayered web stock including at least one layer to be treated, the at least one layer to be treated having a coefficient of thermal expansion significantly differing from a coefficient of thermal expansion of another layer; passing the multilayered web stock at a continuous speed over and in contact with a first concave or reversed-crown wrinkle-reducing roller that spontaneously creates transverse tension stress in the at least one layer to be treated; passing the multilayered web stock at a continuous speed over and in contact with a processing tube, wherein at least one heat source heats the at least one layer to be treated above a glass transition temperature T inducing curvature in the heated portion of the web stock; and cooling the heated portion of the web stock at said curvature by directing a cooling stream at the heated portion of the web stock, wherein the first wrinkle-reducing roller has a center diameter from about 1 to about 4 inches and a differential diameter between ends of the roller and a center of the roller of from about 0.002 to about 0.1 inch, wherein the first wrinkle-reducing roller offsets and suppresses web stock micro ripple formation induced by the processing tube.