Davide Viola, Valle Salimbene, Italy; Marco Viola, Valle Salimbene, Italy; and Andrea Viola, Valle Salimbene, Italy.
Assigned to M.D. Viola Macchine S.R.L., Valle Salimbene, Italy.

Filed: 2/23/22
Issued: 7/29/25

A process for producing pull-up diapers, comprising: producing a composite elastic web comprising at least one web of material and at least one elastic element longitudinally coupled to the at least one web of material; feeding the composite elastic web along a feeding path and according to a feeding direction, by giving the composite elastic web at least one supply tension such that the at least one elastic element has at least one corresponding supply percentage elastic elongation; cutting out openings for the legs in an intermediate portion of the composite elastic web while the composite elastic web advances; applying absorbing inserts on the intermediate portion of the composite elastic web and between successive openings for the previously cut-out legs while the composite elastic web advances, so as to define a series of precursors of pull-up diapers, wherein the intermediate portion of the composite elastic web corresponds to crotches of the pull-up diapers, each provided with the absorbing insert, and two opposite lateral longitudinal portions of the composite elastic web correspond to the waistbands of the pull-up diapers and wherein transverse separation zones separate one precursor from the next; longitudinally folding the composite elastic web so as to bring together opposite flaps of each transverse separation zone and joining together the opposite flaps; and cutting the composite elastic web at the transverse separation zones in order to obtain the single pull-up diapers; wherein cutting out the openings for the legs involves substantially canceling the supply percentage elastic elongation in the central band of the elastic element corresponding to the intermediate portion of the composite elastic web; the composite elastic web has a maximum nominal elongation corresponding to a nominal width of the pull-up diapers to be produced; wherein, when the composite elastic web is at its maximum nominal elongation, the at least one web of material is completely extended and the at least one elastic element has a first percentage elastic elongation; before applying the absorbing inserts, a reduced tension is provided to the composite elastic web, such that the composite elastic web has an elongation less than its maximum nominal elongation and the at least one elastic element has a second percentage elastic elongation less than the first percentage elastic elongation; the reduced tension is conferred before or after cutting out the openings for the legs; and after having cut out the openings for the legs, the second percentage elastic elongation belongs to the two opposite lateral longitudinal portions of the composite elastic web.