Disposable diaper

Patent metadata

Field	Value
Publication number	US-9566199-B2
Application number	US-201314387800-A
Country	US
Kind code	B2
Filing date	Mar 28, 2013
Priority date	Mar 30, 2012
Publication date	Feb 14, 2017
Grant date	Feb 14, 2017

Abstract

The fastening tape included in the disposable diaper has a base sheet, and a hook sheet provided with a plurality of engagement hooks and fixed on the base sheet. The engagement strength of the fastening tape is 0.3 N/30 mm or more, and 1.5 N/30 mm or less. The bending rigidity value in the direction in which the surface of the base sheet of the fastening tape comes close is smaller than the bending rigidity value in the direction in which the surface of the hook sheet of the fastening tape comes close.

First claim

The invention claimed is:

1. A disposable diaper, comprising:
a vertically long absorbent body formed by a front waistline unit, a back waistline unit, and a crotch unit, and including a liquid-retentive absorber;
side flaps provided at least at a part of side edges of the absorbent body in a product widthwise direction of the disposable diaper; and
a fastening tape attached to one of the side flaps, extending outwardly in the product widthwise direction from one of the front waistline unit and the back waistline unit, and configured to be fastened to a remaining one of the front waistline unit and the back waistline unit;
wherein
the fastening tape has
a base sheet, and
a hook sheet provided with a plurality of engagement hooks and fixed on a surface of the base sheet,

the fastening tape has
a tip region not provided with the hook sheet, and
a hook sheet region provided with the hook sheet and inwardly adjacent to the tip region in the product widthwise direction,

an engagement strength of the fastening tape is 0.3 N/30 mm or more, and 1.5 N/30 mm or less,
a density of the engagement hooks is more than 1800 pins/inch,
the base sheet is formed of a first nonwoven fabric layer configured to face toward a wearer's garment and a second nonwoven fabric layer configured to face toward the wearer's skin,
a thickness of the first nonwoven fabric layer is less than a thickness of the second nonwoven fabric layer,
the fastening tape has (i) a first bending rigidity value when the fastening tape is bent in a first direction from the hook sheet toward the base sheet to form a central apex closer to a wearer's garment than edges of the fastening tape, and (ii) a second bending rigidity value when the fastening tape is bent in a second direction from the base sheet toward the hook sheet to form a central apex closer to the wearer's skin than the edges of the fastening tape, and
the first bending rigidity value of the fastening tape is greater than the second bending rigidity value of the fastening tape.

2. The disposable diaper according to claim 1 , wherein
a KES bending rigidity value of the fastening tape in the product widthwise direction and in a product longitudinal direction that is perpendicular to the product widthwise direction is 1.63 gf·cm 2 /cm or less.

3. The disposable diaper according to claim 1 , wherein
the fastening tape further includes:
a proximal region overlapping the side flaps; and
a central region formed only with the base sheet and located between the proximal region and the hook sheet region,

a bending rigidity value in the proximal region is larger than a bending rigidity value in a region of said one of the side flaps that is adjacent to the proximal region,
a bending rigidity value in the hook sheet region is larger than a bending rigidity value in the central region, and
the bending rigidity value in the proximal region is larger than the bending rigidity value in the central region.

4. The disposable diaper according to claim 3 , wherein
a width of the fastening tape in a product longitudinal direction perpendicular to the product widthwise direction is tapered from the proximal region towards the tip region of the fastening tape.

5. The disposable diaper according to claim 4 , wherein
the proximal region has a proximal edge in the product widthwise direction,
the hook sheet region has a distal edge in the product widthwise direction,
a difference between a width of the proximal edge of the proximal region along the product longitudinal direction, and a width of the distal edge of the hook sheet region along the product longitudinal direction is between 4 mm and 8 mm.

6. The disposable diaper according to claim 1 , further comprising a target tape configured to engage with the hook sheet of the fastening tape,
wherein
the target tape, at a skin contact surface side thereof, includes:
an absorber existent region in which the absorbent body overlaps the target tape, and
an absorber non-existent region in which the absorbent body does not overlap the target tape, and

a width of the fastening tape in a product longitudinal direction perpendicular to the product widthwise direction is more than a width of the absorber existent region in the product longitudinal direction.

7. The disposable diaper according to claim 1 , wherein the density of the engagement hooks is more than 2800 pins/inch.

8. The disposable diaper according to claim 5 , wherein
a KES bending rigidity value of the fastening tape in the product widthwise direction and in the product longitudinal direction that is perpendicular to the product widthwise direction is 1.63 gf·cm 2 /cm or less.

9. The disposable diaper according to claim 8 , wherein the density of the engagement hooks is more than 2800 pins/inch.

10. The disposable diaper according to claim 9 , further comprising a target tape configured to engage with the hook sheet of the fastening tape,
wherein
the target tape, at a skin contact surface side thereof, includes:
an absorber existent region in which the absorbent body overlaps the target tape, and
an absorber non-existent region in which the absorbent body does not overlap the target tape, and

a width of the fastening tape in the product longitudinal direction is more than a width of the absorber existent region in the product longitudinal direction.

11. A disposable diaper, comprising:
a vertically long absorbent body formed by a front waistline unit, a back waistline unit, and a crotch unit, and including a liquid-retentive absorber;
side flaps provided at least at a part of side edges of the absorbent body in a product widthwise direction of the disposable diaper; and
a fastening tape attached to one of the side flaps, extending outwardly in the product widthwise direction from one of the front waistline unit and the back waistline unit, and configured to be fastened to a remaining one of the front waistline unit and the back waistline unit;
wherein
the fastening tape has
a base sheet, and
a hook sheet provided with a plurality of engagement hooks and fixed on a surface of the base sheet,

the fastening tape has
a tip region not provided with the hook sheet, and
a hook sheet region provided with the hook sheet and inwardly adjacent to the tip region in the product widthwise direction,

an engagement strength of the fastening tape is 0.3 N/30 mm or more, and 1.5 N/30 mm or less,
a density of the engagement hooks is more than 1800 pins/inch,
the base sheet is formed of a first nonwoven fabric layer configured to face toward a wearer's garment and a second nonwoven fabric layer configured to face toward the wearer's skin,
a density of fibers of the second nonwoven fabric layer is less than a density of fibers of the first nonwoven fabric layer,
the fastening tape has (i) a first bending rigidity value when the fastening tape is bent in a first direction from the hook sheet toward the base sheet to form a central apex closer to the wearer's garment than edges of the fastening tape, and (ii) a second bending rigidity value when the fastening tape is bent in a second direction from the base sheet toward the hook sheet to form a central apex closer to the wearer's skin than the edges of the fastening tape, and
the first bending rigidity value of the fastening tape is greater than the second bending rigidity value of the fastening tape.

12. The disposable diaper according to claim 11 , wherein
the fastening tape further includes:
a proximal region overlapping the side flaps; and
a central region formed only with the base sheet and located between the proximal region and the hook sheet region,

Assignees

• Unicharm Corp

Inventors

• Sakaguchi Satoru

Classifications

• A61F13/622 Primary

  Fabric strip fastener elements, e.g. hook and loop · CPC title

• A61F13/581

  Tab fastener elements combining adhesive and mechanical fastening · CPC title

• A61F13/5644 Primary

  having more than one pair of fasteners · CPC title

• A61F13/5633

  open type diaper · CPC title