Stretchable structure for absorbent article, and method for producing same

Patent metadata

Field	Value
Publication number	US-11083637-B2
Application number	US-201716070155-A
Country	US
Kind code	B2
Filing date	Jan 25, 2017
Priority date	Jan 29, 2016
Publication date	Aug 10, 2021
Grant date	Aug 10, 2021

Abstract

A first sheet layer made of a nonwoven fabric; a second sheet layer made of a nonwoven fabric opposed to one side of the first sheet layer; and a plurality of elongated elastically stretchable members provided along the stretchable direction at intervals from each other between the first sheet layer and the second sheet layer are provided. At least a part of each end of the elastically stretchable member is fixed to at least one of the first sheet layer and the second sheet layer only via a first hot melt adhesive. The first sheet layer and the second sheet layer are bonded via a second hot melt adhesive in a range in the stretchable direction corresponding to a space between the both ends of the elastically stretchable member. The holding power of the first hot melt adhesive is higher than the second hot meld adhesive.

First claim

The invention claimed is:

1. A stretchable structure of an absorbent article, comprising:
a first sheet layer made of a nonwoven fabric;
a second sheet layer made of a nonwoven fabric and opposed to one side of the first sheet layer; and a plurality of elongated elastically stretchable members provided along a stretchable direction at intervals from each other between the first sheet layer and the second sheet layer,
wherein at least one elastically stretchable member is fixed to at least one of the first sheet layer and the second sheet layer via a first hot melt adhesive at each of a pair of adhesion sites located at both ends of a stretchable region in the stretchable direction,
wherein the first sheet layer and the second sheet layer are bonded via a second hot melt adhesive in a range at least in the stretchable direction corresponding to a space between the pair of the adhesion sites,
wherein each adhesion site of the pair of adhesion sites has a single application portion where the at least one elastically stretchable member is fixed to at least one of the first sheet layer and the second sheet layer via only the first hot melt adhesive and has double application portions by the first hot melt adhesive and the second hot melt adhesive, and
wherein a holding power of the first hot melt adhesive is higher than a holding power of the second hot melt adhesive.

2. The stretchable structure of an absorbent article according to claim 1 , wherein the melt viscosity of the first hot melt adhesive is higher than the melt viscosity of the second hot melt adhesive.

3. The stretchable structure of an absorbent article according to claim 1 , wherein the loop tack adhesive strength of the second hot melt adhesive is higher than the loop tack adhesive strength of the first hot melt adhesive.

4. The stretchable structure of an absorbent article according to claim 1 ,
wherein the second hot melt adhesive is provided in an intermittent pattern, in which adhesive portions and non-adhesive portions are alternated repeatedly at least in the stretchable direction, over a range in the stretchable direction including the pair of the adhesion sites, and
the first hot melt adhesive is continued in the stretchable direction so as to have an application width longer than the application width of the second hot melt adhesive at least at passing positions of the elastically stretchable members.

5. The stretchable structure of an absorbent article according to claim 4 ,
wherein sheet bonded portions, at which the first sheet layer and the second sheet layer are bonded via the second hot melt adhesive, are disposed in a striped pattern that is intermittent in the longitudinal direction of the elastically stretchable members and continuous in a direction intersecting the elastically stretchable members, and
the width of each sheet bonded portion in the stretchable direction is 0.5 to 4 mm, and the interval between adjacent two sheet bonded portions is 4 to 8 mm.

6. The stretchable structure of an absorbent article according to claim 5 , wherein the first hot melt adhesive is disposed intermittently in a direction orthogonal to the elastically stretchable members only at positions overlapping with the elastically stretchable members.

7. The stretchable structure of an absorbent article according to claim 1 , wherein:
the absorbent article is an underpants-type disposable diaper, in which an outer member disposed in a front body and a back body and an inner member attached to the outer member and including an absorber are provided, both side edges of the outer member of the front body and both side edges of the outer member of the back body are bonded to each other, a range in a front-back direction corresponding to the bonded side edges is an annular lower torso portion, and a waist opening and a pair of right and left leg openings are formed, and
the stretchable structure is provided in a region including at least both sides in the width direction of a position overlapping with the inner member in the outer member such that the elastically stretchable members are along the width direction.

8. The stretchable structure of an absorbent article according to claim 2 , wherein the loop tack adhesive strength of the second hot melt adhesive is higher than the loop tack adhesive strength of the first hot melt adhesive.

9. The stretchable structure of an absorbent article according to claim 2 ,
wherein the second hot melt adhesive is provided in an intermittent pattern, in which adhesive portions and non-adhesive portions are alternated repeatedly at least in the stretchable direction, over a range in the stretchable direction including the pair of the adhesion sites, and
the first hot melt adhesive is continued in the stretchable direction so as to have an application width longer than the application width of the second hot melt adhesive at least at passing positions of the elastically stretchable members.

10. The stretchable structure of an absorbent article according to claim 3 ,
wherein the second hot melt adhesive is provided in an intermittent pattern, in which adhesive portions and non-adhesive portions are alternated repeatedly at least in the stretchable direction, over a range in the stretchable direction including the pair of the adhesion sites, and
the first hot melt adhesive is continued in the stretchable direction so as to have an application width longer than the application width of the second hot melt adhesive at least at passing positions of the elastically stretchable members.

11. The stretchable structure of an absorbent article according to claim 2 , wherein
the absorbent article is an underpants-type disposable diaper, in which an outer member disposed in a front body and a back body and an inner member attached to the outer member and including an absorber are provided, both side edges of the outer member of the front body and both side edges of the outer member of the back body are bonded to each other, a range in a front-back direction corresponding to the bonded side edges is an annular lower torso portion, and a waist opening and a pair of right and left leg openings are formed, and
the stretchable structure is provided in a region including at least both sides in the width direction of the inner member in the outer member such that the elastically stretchable members are along the width direction.

12. The stretchable structure of an absorbent article according to claim 3 , wherein
the absorbent article is an underpants-type disposable diaper, in which an outer member disposed in a front body and a back body and an inner member attached to the outer member and including an absorber are provided, both side edges of the outer member of the front body and both side edges of the outer member of the back body are bonded to each other, a range in a front-back direction corresponding to the bonded side edges is an annular lower torso portion, and a waist opening and a pair of right and left leg openings are formed, and
the stretchable structure is provided in a region including at least both sides in the width direction of the inner member in the outer member such that the elastically stretchable members are along the width direction.

13. The stretchable structure of an absorbent article according to claim 4 , wherein
the absorbent article is an underpants-type disposable diaper, in which an outer member disposed in a front body and a back body and an inner member attached to the outer member and including an absorber are provided, both side edges of the outer member of the front body and both side edges of the outer member of the back body are bonded

Assignees

• Daio Seishi Kk

Inventors

• Ishikawa Yasuko

Classifications

• A61F13/15739 Primary

  Sealing, e.g. involving cutting · CPC title

• B29C65/18

  using heated tools · CPC title

• B32B5/26

  another layer {next to it} also being fibrous or filamentary {(relative arrangement of fibres or filaments of different layers B32B5/12)} · CPC title

• A61F13/49012

  the elastic means being elastic panels · CPC title

• B29C65/526

  by printing or by transfer from the surfaces of elements carrying the adhesive, e.g. using brushes, pads, rollers, stencils or silk screens · CPC title