Patent ID: 7449015

Claim:
A pants-type disposable wearing article comprising an elastically stretchable outer sheet defining front and rear waist regions opposed to each other and a crotch region extending between these waist regions, and a liquid-absorbent panel attached to an inner surface of said outer sheet and extending between said front and rear waist regions, said outer sheet having waist regions' upper margins extending in said front and rear waist regions in a transverse direction, waist-circumferential lateral margins extending in a longitudinal direction and crotch region's lateral margins extending in said crotch region in the leg-circumferential direction, said front and rear waist regions being connected along said waist-circumferential margins so as to define a waist-opening and a pair of leg-openings, and first elastic members extending in the leg-circumferential direction are attached to said crotch region's lateral margins of said outer sheet, said pants-type disposable wearing article further comprising: said outer sheet and said first elastic members being joined together while said outer sheet being stretched at a given stretching ratio in the transverse direction and said first elastic members being stretched at a given stretching ratio in the leg-circumferential direction so as to ensure that said outer sheet and said first elastic members have substantially same dimensions as measured in the leg-circumferential direction after these outer sheet and first elastic members have been relaxed and that said crotch region's lateral margins are substantially planar without undulation in a thickness direction of said outer sheet; wherein said outer sheet comprises zones which underlie and are coextensive with the first elastic members, said zones being wrinkle-free when said outer sheet and said first elastic members are all relaxed; and wherein a peripheral edge of each of said leg-openings comprises a wrinkle-free section defined by one of said zones, and a wrinkled section defined by an associated one of transversely opposite edges of the panel, said transversely opposite edges of the panel having further elastic members attached thereto.