PROBLEM TO BE SOLVED: To provide an underpants type disposable diaper having an excellent dynamic fitting property on the belly side.SOLUTION: By varying at least one of a longitudinal arrangement interval, a diameter, an elongation rate at the time of fixing, and the number between a waist edge part elastic expansion/contraction member 17 and an abdominal region elastic expansion/contraction member 20, an underpants type disposable diaper satisfies the relation or Ffd>Ffw>Ffi, when tensile force of a front waist edge part region fw when elastic-deformed in the width direction is set as Ffw, tensile force of an ilium abutment region fi when elastic-deformed in the width direction is set as Ffi, and tensile force of an abdominal region abutment region fd when elastic-deformed in the width direction is set as Ffd.COPYRIGHT: (C)2014,JPO&INPIT【課題】腹側における動的なフィット性に優れるパンツタイプおむつを提供する。【解決手段】前ウエスト縁部領域fwの幅方向の弾性変形時引張力をFfw、腸骨当接領域fiの幅方向の弾性変形時引張力をFfi、下腹部当接領域fdの幅方向の弾性変形時引張力をFfdとしたとき、ウエスト縁部弾性伸縮部材17及び下腹部弾性伸縮部材20の二者間で、縦方向配置間隔、太さ、固定時の伸長率及び本数の少なくとも一つを異ならしめることにより、Ffd>Ffw>Ffiの関係を満たすように構成する。【選択図】図8
