PROBLEM TO BE SOLVED: To provide an underpants type disposable diaper in which being turned up is suppressed in wearing, and which has a leg surrounding extension part which can maintain a surface shape easily.SOLUTION: There is provided a production method of an underpants type disposable diaper (1) having an absorber (12) whose longitudinal direction is along a vertical direction, and an external sheet (14) overlapping on a non-skin side of the absorber. The method comprises: a deposition area formation step for folding from outside to inside, both end parts of the external sheet (14) in the lateral direction, depositing the folded parts, for forming deposition areas (62) having a prescribed length in the lateral direction an elastic member arrangement step for arranging an elastic member (61) which stretches in the vertical direction on a prescribed area of the external sheet (14) and a leg surrounding extension part forming step for folding both end parts of the external sheet (14) in the lateral direction, from outside to inside, again, for forming leg surrounding extension parts (60) extending in both sides of the lateral direction of the absorber, while at least a part of the elastic member overlaps the deposition area (61) in the lateral direction.SELECTED DRAWING: Figure 4COPYRIGHT: (C)2018,JPO&INPIT【課題】着用時にめくれが生じにくく、面形状を維持しやすい脚回り延出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】長手方向が縦方向に沿った吸収体(12)と、前記吸収体の非肌側に重ねられた外装シート(14)と、を備えるパンツ型吸収性物品(1)の製造方法であって、横方向において、外装シート(14)の両端部を外側から内側に折り返し、折り重ねられた部分を溶着して前記横方向に所定の長さを有する溶着領域(62)を形成する溶着領域形成工程と、外装シート(14)の所定の領域に縦方向に伸縮する弾性部材(61)を配置する弾性部材配置工程と、横方向において外装シート(14)の両端部を外側から内側に再度折り返すことにより、前記吸収体の前記横方向の両側に延出しつつ、前記横方向において前記弾性部材の少なくとも一部が溶着領域(61)と重複した脚回り延出部(60)を形成する脚回り延出部形成工程と、を有する。【選択図】図4
