PROBLEM TO BE SOLVED: To provide an pull-up disposable diaper having side sealing portions equipped with an enough joint strength and a peeling easiness.SOLUTION: In the pull-up disposable diaper, both side parts of an outer decorative sheet of a front body F joined with side sealing portions 21 and 22 and both side parts of the outer decorative sheet of a back body B are jointed so that at least one or more lamination number changing portions in which the number of lamination of sheet raw materials to be joined are changed may be present in the intermediate parts in the longitudinal direction. The side sealing portions 21 and 22 are formed so that at least side edges of the insides in the width directions form wavy shapes, and the lamination number changing portions are positioned between the top points of the outsides in the width direction on the wavy side edges and adjacent top points on the insides in the width direction on the waist side.COPYRIGHT: (C)2012,JPO&INPIT【課題】充分な接合強度と引き剥がしやすさとを備えたサイドシール部を有するパンツ型使い捨ておむつを提供する。【解決手段】パンツ型使い捨ておむつにおいて、サイドシール部21,22で接合される前身頃Fにおける外装シートの両側部と後身頃Bにおける外装シートの両側部とは、その縦方向中間部に、接合されるシート素材の積層数が変化する積層数変化部を少なくとも一個所有するように接合される。前記サイドシール部21,22は、少なくとも幅方向内側の側縁が波状をなすとともに、この波状の側縁における幅方向外側の頂点とそのウエスト側に隣接する幅方向内側の頂点との間に、前記積層数変化部が位置するように形成される。【選択図】図8
