Elastic sheet, underpants-type absorbent article, and method for manufacturing elastic sheet

A stretchable sheet comprising:

• a first sheet;
• a second sheet joined to the first sheet by welded portions;
• and
• an elastic member that is disposed between the first sheet and the second sheet and stretches and contracts in a continuous direction in which the elastic member extends, wherein
• the welded portions are disposed on both sides of the elastic member in an intersecting direction intersecting with the continuous direction,
• welded portion pairs are disposed in which the elastic member is sandwiched and restrict a position of the elastic member in the intersecting direction with respect to the first sheet and the second sheet,
• the elastic member has a damaged portion where a part of a surface of the elastic member is damaged,
• the welded portion pairs include a first welded portion pair and a second welded portion pair that is disposed adjacent to the first welded portion pair in the continuous direction,
• the damaged portion is disposed between the first welded portion pair and the second welded portion pair in the continuous direction.