Abstract: A continuous web of paper has a longitudinally extending marginal part folded over onto an adjacent longitudinally extending second part of the web. The web is in tension, and the second web part has a transverse slit. During the folding step, the marginal part is folded out of the plane of the web thereby increasing the tension on the second web part. A ribbon of flexible material is disposed beneath, and conformed to the contours of, the second web part during the folding step, to absorb some of the tension on the second part so as to prevent transverse tearing from the transverse slit across the second part of the web.

Abstract: A composite strip is formed, during a folding step, from a continuous cover strip folded around a continuous, multi-ply inner strip. The cover strip has longitudinally spaced transverse slits therein and is tensioned during the folding step. A sharp, neat fold is obtained without transversely tearing the cover strip.