Abstract: A method for forming a skin-contacting topsheet of disposable diaper with an elastic opening, wherein the opening 16 formed in the skin-contacting topsheet of a disposable diaper is elasticized along its whole peripheral edge and reinforced so as to form uniform gathers along the whole peripheral edge.The skin-contacting topsheet comprises a pair of sheet members overlapping side by side and having mutually opposed inner side edges, respectively, which are provided with cutouts so that each pair of mutually opposed cutouts form each opening, then elastic members are provided along halves of the opening's whole peripheral edge and these elastic members are covered with a part of the skin-contacting topsheet.

Abstract: To prevent a part of excretions having missed an opening formed in a skin-contacting topsheet 14 of a disposable diaper from diffusively flowing over the top surface of this topsheet 14, the opening 16 is provided along the laterally opposite sides thereof with a pair of first flaps 17 opposed to and spaced from each other by a relatively small distance and a pair of second flaps 18 similarly opposed to and spaced from each other by a relatively large distance so that the part of excretions having missed the opening 16 defined by the laterally opposite side edges of the first flaps 17 may be reliably dammed by the second flaps 18 and thereby the diffusive flowing of excretion may be avoided.