Stretchable and contractible sheet and absorbent article
A stretchable/contractible sheet having an up-down direction and a left-right direction intersecting each other is provided. The stretchable and contractible sheet includes: a first welded-portion row including a plurality of welded portions arranged side-by-side in the up-down direction; and a second welded-portion row including the plurality of welded portions located adjacent to the first welded-portion row on a one side in the left-right direction. The first welded-portion row includes: a first convex portion protruding toward the one side; and a second convex portion. The second welded-portion row includes a third convex portion protruding toward another side opposite to the one side in the left-right direction.
1. An absorbent article having an up-down direction and a left-right direction intersecting each other, comprising:
an absorbent main body that absorbs excrement;
a front band member disposed along the left-right direction and joined to a front-upper-end portion of the absorbent main body; and
a back band member disposed along the left-right direction separately from the front band member and joined to a back-upper-end portion of the absorbent main body, wherein the front band member and the back band member each comprise:
a first sheet;
a second sheet;
a plurality of welded portions that joins the first sheet and the second sheet;
a plurality of elastic members that is stretchable and contractible in the left-right direction;
a first welded-portion row that comprises the plurality of welded portions arranged side-by-side in the up-down direction; and
a second welded-portion row that comprises the plurality of welded portions arranged side-by-side in the up-down direction, and located adjacent to the first welded-portion row on a one side in the left-right direction,
the plurality of elastic members is arranged with a space in the up-down direction and between the first sheet and the second sheet,
each of the elastic members is sandwiched between two welded portions adjacent in the up-down direction with contracting in the left-right direction, and is attached to the first sheet and the second sheet,
the first welded-portion row comprises:
a first convex portion that protrudes toward the one side in the left-right direction and
a second convex portion located adjacent to the first convex portion in the up-down direction,
the second welded-portion row comprises a third convex portion that protrudes toward another side in the left-right direction,
when the elastic members are not stretched in the left-right direction, an other-side end of the third convex portion is located closer to the another side than a straight line that connects a one-side end of the first convex portion and a one-side end of the second convex portion,
when the elastic members are stretched in the left-right direction, the other-side end of the third convex portion is located closer to the one side than the straight line,
an end portion of the front band member in the left-right direction is joined to an end portion of the back band member in the left-right direction by a first side seal portion,
another end portion of the front band member in the left-right direction is joined to another end portion of the back band member in the left-right direction by a second side seal portion,
the first welded-portion row is located between the first side seal portion and the second side seal portion in the left-right direction, and
the second welded-portion row is located between the first side seal portion and the second side seal portion in the left-right direction.
2. The absorbent article according to claim 1 , wherein
of the plurality of welded portions included in the first welded-portion row and the second welded-portion row,
each pair of two welded portions adjacent in the up-down direction comprises a portion overlapping in the left-right direction.
3. The absorbent article according to claim 2 , wherein
a length of the portion that is included in the two welded portions adjacent in the up-down direction and in which the two welded portions overlap in the left-right direction is larger than
a length of a portion that is included in the two welded portions and in which the two welded portions do not overlap in the left-right direction.
4. The absorbent article according to claim 2 , wherein the first welded-portion row and the second welded-portion row extend downward in the up-down direction and meanders in the left-right direction.
5. The absorbent article according to claim 1 , wherein a length of the welded portion in the left-right direction is larger than a length of the welded portion in the up-down direction.
6. The absorbent article according to claim 1 , wherein a length of the welded portion in the up-down direction is larger than an up-down-direction space of two adjacent welded portions.
7. The absorbent article according to claim 1 , wherein
the plurality of elastic members comprises a first elastic member and a second elastic member adjacent to the first elastic member in the up-down direction, and
a first space in the up-down direction between the first elastic member and the second elastic member is smaller than a second space in the up-down direction between the one-side end of the first convex portion and the one-side end of the second convex portion.
8. The absorbent article according to claim 7 , wherein the first space is smaller than half the second space.
9. The absorbent article according to claim 1 , wherein
in the up-down direction,
a first space of the elastic members disposed in the front band member is different from a second space of the elastic members disposed in the back band member.
10. The absorbent article according to claim 9 , wherein the first space is smaller than the second space.
11. An absorbent article having an up-down direction and a left-right direction intersecting each other comprising:
an absorbent main body that absorbs excrement;
a front band member disposed along the left-right direction and joined to a front-upper-end portion of the absorbent main body; and
a back band member disposed along the left-right direction separately from the front band member and joined to a back-upper-end portion of the absorbent main body, wherein the front band member and the back band member each comprise:
a first sheet;
a second sheet;
a plurality of welded portions that joins the first sheet and the second sheet;
a plurality of elastic members that is stretchable and contractible in the left-right direction;
a first welded-portion row that comprises the plurality of welded portions arranged side-by-side in the up-down direction; and
a second welded-portion row that comprises the plurality of welded portions arranged side-by-side in the up-down direction, and located adjacent to the first welded-portion row on a one side in the left-right direction,
the plurality of elastic members is arranged with a space in the up-down direction and between the first sheet and the second sheet,
each of the elastic members is sandwiched between two welded portions adjacent in the up-down direction with contracting in the left-right direction, and is attached to the first sheet and the second sheet;
the first welded-portion row comprises:
a first convex portion that protrudes toward the one side in the left-right direction; and
a second convex portion located adjacent to the first convex portion in the up-down direction,
the second welded-portion row comprises a third convex portion that protrudes toward another side in the left-right direction,
when the elastic members are not stretched in the left-right direction, an other-side end of the third convex portion is located closer to the another side than a straight line that connects a one-side end of the first convex portion and a one-side end of the second convex portion,
the elastic members are attached at a stretching ratio that produces a contraction force that is capable of moving the other-side end of the third convex portion so that:
when the elastic members are stretched in the left-right direction, the other-side end of the third convex portion is located closer to the one side than the straight line; and
when the elastic members are not stretched in the left-right direction, the other-side end of the third convex portion is located closer to the another side than the straight line,
an end portion of the front band member in the left-right direction is joined to an end portion of the back band member in the left-right direction by a first side seal portion,
another end portion of the front band member in the left-right direction is joined to another end portion of the back band member in the left-right direction by a second side seal portion,
the first welded-portion row is located between the first side seal portion and the second side seal portion in the left-right direction, and
the second welded-portion row is located between the first side seal portion and the second side seal portion in the left-right direction.
12. The absorbent article according to claim 11 , wherein the elastic member is attached at a stretching ratio not less than twice and not more than third times.
13. The absorbent article according to claim 11 , wherein in the left-right direction, a space of two adjacent welded portions is less than or equal to 6 mm.
14. The absorbent article according to claim 11 , wherein
in the up-down direction,
a first space of the elastic members disposed in the front band member is different from a second space of the elastic members disposed in the back band member.
15. The absorbent article according to claim 14 , wherein the first space is smaller than the second space.