Patent ID: 6821610
Filing Date: 2004-11-23
Classification: B32B,Y10T

Abstract:
An elastic film laminate comprising:(a) a first film that is elastomeric in at least one direction, and can be reversibly stretched in a first stretching processs by a length &Dgr;lA during a deformation without demonstrating substantial residual deformation &Dgr;la; and (b) second and third films made of a deformable plastic connected to one side or respecitvely to each side of said first film in localized connection regions less than the entire length of said first film, wherein said second and third film have different degrees of permanent deformation from each other; wherein in a renewed deformation of the the film laminate above a limit range of deformation where &Dgr;l>&Dgr;lA applies, said second and third films exhibit a reaction force that causes the tensile force required for further stretching of the laminate to increase suddenly; wherein the tear resistances of said second and third films are adjusted so that if the tensile force is increased further, stretching of said second and third films by at least 10% and 20% of their length, respectively, is still possible beyond &Dgr;lA before tear, and wherein said second film has a degree of deformation that is at least 10% higher than that of said third film after the stretching process, so that when repeated stretching of the film laminate occurs, a stress-strain diagram will show two gradations.