PROBLEM TO BE SOLVED: To provide an underpants type disposable diaper comprising leakage prevention walls, which can suppress falling of a standing part of each leakage prevention wall, and achieve preferable fitness.SOLUTION: An underpants type disposable diaper comprises an absorbent body and an outer sheet which is provided on a non-skin side. Each of both sides of the absorbent body comprises a leakage prevention wall 50 along a longitudinal direction. The leakage prevention wall 50 comprises: a junction where surfaces on one side of a thickness direction are jointed, on a position where, in at least a vertical direction, a length in the lateral direction of the outer sheet is minimum a non-junction where the surfaces in the thickness direction are not jointed, in an upper area of the junction in the vertical direction and a body junction for jointing the absorbent body to the outer sheet. A width in the lateral direction of the body junction on a position where the lateral length of the outer sheet is minimum is narrower than a width in the lateral direction of the body junction in both end positions of the body junction in the longitudinal direction.SELECTED DRAWING: Figure 6COPYRIGHT: (C)2018,JPO&INPIT【課題】防漏壁を有するパンツ型使い捨ておむつにおいて、防漏壁の起立部分が倒れてしまうことを抑制しつつ良好なフィット性を実現する。【解決手段】吸収性本体と非肌側に設けられた外層シートとを備えたパンツ型使い捨ておむつであって、前記吸収性本体の両側にはそれぞれ、長手方向に沿った防漏壁50が設けられており、前記防漏壁50は、少なくとも縦方向において前記外層シートの前記横方向の長さが最小となる位置に、厚さ方向の一方側の面同士が接合された接合部を有し、前記縦方向において前記接合部よりも上側の領域に、前記厚さ方向の面同士が接合されていない非接合部を有し、前記吸収性本体を前記外層シートに接合する本体接合部を有し、少なくとも前記最小となる位置における前記本体接合部の前記横方向の幅は、前記本体接合部の前記長手方向の両端位置おける前記本体接合部の前記横方向の幅よりも狭い。【選択図】図6
