Method for forming stretchable structure for absorbent article and stretchable structure for absorbent article

A method for forming a stretchable structure for an absorbent article, comprising:

• while rotating a first roll with joint convex parts provided at circumferential intervals on an outer peripheral surface and a second roll opposed to the first roll, in opposite directions around axis centers thereof, passing a first sheet layer, a second sheet layer, and elongated resilient and elastic members continuously disposed in an MD direction between these sheet layers, between the first roll and the second roll;
• and
• pressurizing and heating by sandwiched between the joint convex parts of the first roll and the second roll to form sheet joined sections welding the first sheet layer and the second sheet layer in such a manner as to cross the resilient and elastic members and have MD-direction intervals therebetween,
• wherein the joint convex parts extend continuously in a direction crossing the resilient and elastic members and perpendicular to the MD direction,
• wherein circumferentially continuous grooves are formed on a pressurization surface of only the second roll in a partial range of a rotation period of the second roll,
• one of the first sheet layer and the second sheet layer is in contact with the second roll having the grooves and the resilient and elastic members are guided to wrap around the second roll having the grooves, the resilient and elastic members and the one of the first sheet layer and the second sheet layer in contact with the grooves are pressed into the grooves by line tension before the first sheet layer and the second sheet layer are pressurized and heated, and
• under the pressurization and heating, passage sections of the resilient and elastic members are pressurized and heated in positions including the grooves and non-passage sections of the resilient and elastic members are pressurized and heated in positions not including the grooves.