CN110114045B

CN110114045B - Underpants type absorbent article

Info

Publication number: CN110114045B
Application number: CN201780080621.7A
Authority: CN
Inventors: 川端训功; 市川诚
Original assignee: Unicharm Corp
Current assignee: Unicharm Corp
Priority date: 2016-12-27
Filing date: 2017-10-24
Publication date: 2022-03-15
Anticipated expiration: 2037-10-24
Also published as: WO2018123237A1; CN110114045A; JP6718809B2; JP2018102654A

Abstract

The present invention relates to a pants-type absorbent article (1) having an absorbent main body (10) and a pair of belt portions (20, 30). The band (20, 30) has an elastic member (23, 33) joined between the skin-side sheet (21, 31) and the non-skin-side sheet (22, 32) with an adhesive, the elastic member being stretchable and contractible in the transverse direction. The belt portions (20, 30) have a pair of joining regions (60) in each of which a non-skin-side surface of a longitudinal end portion of the absorbent main body (10) is joined to a skin-side surface of the skin-side sheet (21, 31). The skin side sheet (21, 31) has a fiber basis weight greater than that of the non-skin side sheet (22, 32). The amount per unit length of the adhesive joining the elastic member (23, 33) and the skin-side sheet (21, 31) is smaller than the amount per unit length of the adhesive joining the elastic member (23, 33) and the non-skin-side sheet (22, 32).

Description

Underpants type absorbent article

Technical Field

The present invention relates to an underpants type absorbent article.

Background

As one example of a pants-type absorbent article, patent document 1 discloses a pull-on disposable diaper which includes an outer body and an absorbent main body fixed to an inner surface side of the outer body, and in which a pair of side seal portions are formed by joining both side portions of a front portion of the outer body and both side portions of a rear portion of the outer body. In patent document 1, MFR (melt floating ratio) of the outermost sheet constituting the outer body is set to be higher than MFR of the innermost sheet, thereby improving the joining strength of the side seal portion while also obtaining flexibility on the outer side. In addition, from the viewpoint of achieving uniform melting of the innermost sheet, it is preferable that the basis weight (grammage) of the innermost sheet is set smaller than the basis weight (grammage) of the outermost sheet.

List of documents

Patent document

Patent document 1: japanese patent application laid-open No. 2013-102886

Disclosure of Invention

Technical problem

In the pant-type absorbent article, an elastic member is fixed in a laterally stretched state between an outermost sheet (non-skin side sheet) and an innermost sheet (skin side sheet) so that front and rear portions (belt portions) of an outer body fit the waist of a wearer. In addition, the absorbent main body is fixed to the innermost sheet. For this reason, if the basis weight of the innermost sheet is low as in patent document 1, the contraction force of the elastic member is less likely to be buffered by the innermost sheet and may be transmitted to the absorbent main body. If the absorbent main body contracts due to the influence of the contraction of the elastic member, wrinkles are formed in the absorbent main body, and thus excrement may leak, and the comfort is lowered.

The present invention has been achieved in view of the conventional problems such as described above, and an aspect of the present invention is to provide a pants-type absorbent article in which an absorbent main body is less likely to be affected by contraction of a belt portion.

Problem solving scheme

A main aspect of the present invention for achieving the above-described aspect is a pants-type absorbent article having a vertical direction, a lateral direction, and a thickness direction, the pants-type absorbent article including: an absorbent main body having a longitudinal direction coinciding with the vertical direction and folded once in the longitudinal direction; and a pair of belt portions extending in the transverse direction, each of the belt portions including: a skin-side sheet; a non-skin side sheet; and an elastic member stretchable and contractible in the transverse direction and joined between the skin-side sheet and the non-skin-side sheet by use of an adhesive; a pair of joining regions provided such that, in each of the pair of joining regions, a non-skin side surface of each of the longitudinal end portions of the absorbent main body is joined to a skin side surface of the skin side sheet of each of the belt portions, the skin side sheet has a fiber basis weight greater than that of the non-skin side sheet, and an amount per unit length of an adhesive joining the elastic member to the skin side sheet is smaller than that of the adhesive joining the elastic member to the non-skin side sheet.

Features of the present invention other than those described above will become apparent by reading the description of the present specification with reference to the accompanying drawings.

The invention has the advantages of

According to the present invention, it is possible to provide a pants-type absorbent article in which the absorbent main body is less likely to be affected by the contraction of the belt portion.

Drawings

Fig. 1 is a schematic front view of a pull-on disposable diaper 1 according to a first embodiment.

Fig. 2 is a schematic plan view of the diaper 1 in an unfolded and stretched state when viewed from the skin side.

Fig. 3 is a schematic cross-sectional view taken along line AA in fig. 2.

Fig. 4 is a schematic cross-sectional view taken along line BB in fig. 2.

Fig. 5 shows an explanatory view of the amounts of the

adhesives

50 and 51 by which the

elastic members

23 and 33 are joined to the skin-

side sheets

21 and 31 and the non-skin-

side sheets

22 and 32.

Fig. 6 is an explanatory view of the joining region 60.

Fig. 7A is an explanatory view of the first coating region 64, and fig. 7B is an explanatory view of the second coating region 65.

Fig. 8 is an explanatory view of a joint region 60 of the diaper 1 according to the second embodiment.

Detailed Description

At least the following matters will become clear from the description of the present specification and the accompanying drawings.

A pants-type absorbent article having a vertical direction, a lateral direction and a thickness direction,

the pants-type absorbent article includes:

an absorbent main body having a longitudinal direction coinciding with the vertical direction and folded once in the longitudinal direction; and

a pair of band portions extending in the transverse direction,

each of the band portions includes:

a skin-side sheet;

a non-skin side sheet; and

an elastic member that is stretchable and contractible in the transverse direction and is joined between the skin-side sheet and the non-skin-side sheet by use of an adhesive,

a pair of joining regions provided such that, in each of the pair of joining regions, a non-skin-side surface of each of longitudinal end portions of the absorbent main body is joined to a skin-side surface of the skin-side sheet of each of the belt portions,

the skin side sheet has a fiber basis weight greater than the fiber basis weight of the non-skin side sheet,

an amount per unit length of the adhesive joining the elastic member to the skin side sheet is smaller than an amount per unit length of the adhesive joining the elastic member to the non-skin side sheet.

According to the pants-type absorbent article, the side skin sheet has a high cushioning ability, and the cushioning ability is less likely to be impaired by the adhesive, and therefore the contraction force of the elastic member is likely to be cushioned by the side skin sheet. Therefore, the absorbent main body is less likely to be affected by the contraction of the belt portion, and wrinkles are less likely to be formed in the absorbent main body.

It is a pants-type absorbent article in which:

at least one of the pair of engagement regions comprises:

a pair of first regions elongated in the transverse direction;

and

a pair of second regions elongated in the vertical direction and connecting lateral ends of the pair of first regions, and

wherein a non-joined region where the absorbent main body is not joined to the skin-side sheet is disposed at a position between the pair of first regions and between the pair of second regions.

According to this pant-type absorbent article, the joined region joining the absorbent main body and the belt portion has a smaller size due to the non-joined region, and the absorbent main body is less likely to be affected even by the contraction of the belt portion. In addition, due to the pair of first regions, the lower end of the belt portion and the upper end of the absorbent main body can be prevented from rolling up. In addition, when the absorbent article is pulled up, the pulling-up force can be transmitted from the belt portion to the absorbent main body due to the pair of second regions, and the absorbent main body can be easily pulled up.

It is a pants-type absorbent article in which:

the vertical length of the non-joined region is greater than the vertical length of the lower first region of the pair of first regions.

According to this pant-type absorbent article, the joining region joining the absorbent main body and the belt portion has an even smaller size, and the absorbent main body is even less likely to be affected by the contraction of the belt portion.

It is a pants-type absorbent article in which:

the upper first region of the pair of first regions has a vertical length greater than a vertical length of the lower first region of the pair of first regions.

According to this pant-type absorbent article, the joining region joining the absorbent main body and the belt portion has an even smaller size, and the absorbent main body is even less likely to be affected by the contraction of the belt portion. At the same time, the upper end of the absorbent body is firmly joined to the belt portion, so that a reduction in the comfort caused by the rolling-up of the absorbent body can be prevented.

It is a pants-type absorbent article in which:

in the region of the pair of joining regions,

the joined region on the front side of the wearer has the non-joined region, and

the bonded region on the back side of the wearer is free of the non-bonded region.

According to this pant-type absorbent article, even if the rear belt portion is more likely to become separated from the absorbent main body due to friction with another object during, for example, sleep than the front belt portion, the rear belt portion is firmly joined to the absorbent main body. Further, the absorbent main body is less likely to be affected by the contraction of the front belt portion.

It is a pants-type absorbent article in which:

each of the belt portions has a plurality of elastic members arranged side by side in the vertical direction, and

in each of the band portions, a first end of the band portion,

all of the elastic members overlapping the absorbent main body in the thickness direction overlap the joining region in the thickness direction.

According to the pants-type absorbent article, local contraction of each belt portion due to large contraction of the elastic member that does not overlap the joining region can be prevented.

It is a pants-type absorbent article in which:

each of the belt portions has a plurality of elastic members arranged side by side in the vertical direction,

the belt portion on the wearer's back side has a protruding region which protrudes further downward than the belt portion on the wearer's front side, and

a portion of the joining region that overlaps, in the thickness direction, with an elastic member of the plurality of elastic members that is arranged in the protruding region has a smaller lateral length than a portion of the joining region that overlaps, in the thickness direction, with another elastic member of the plurality of elastic members.

According to this pant-type absorbent article, the rear joint region has a smaller size, and the absorbent main body is less likely to be affected by the contraction of the rear belt portion.

It is a pants-type absorbent article in which:

among the plurality of elastic members arranged in the protruding region,

a portion of the joining region that overlaps with the lower elastic member in the thickness direction has a smaller lateral length than a portion of the joining region that overlaps with the upper elastic member in the thickness direction.

According to this pant-type absorbent article, the rear joint region has an even smaller size, and the absorbent main body is less likely to be affected by the contraction of the rear belt portion.

It is a pants-type absorbent article in which:

the absorbent main body has an absorber, and

at least one of a portion of the absorbent body located on the front side of the wearer and a portion of the absorbent body located on the back side of the wearer is thicker than a portion of the absorbent body located in the crotch region of the wearer.

According to this pants-type absorbent article, the portion of the absorbent body that overlaps with the belt portion is thicker and has higher rigidity, and therefore the absorbent main body is less likely to be affected even by the contraction of the belt portion.

Hereinafter, an embodiment of a pants-type absorbent article according to the present invention will be described by way of an example of a pull-on disposable diaper for adults. It should be noted that the pant-type absorbent article according to the invention is not limited to diapers for adults, but is also applicable to diapers for infants, and pull-on sanitary napkins, for example.

In the first embodiment, the present invention is not limited to the specific example

Basic Structure of Pull-on Disposable diaper

Fig. 1 is a schematic front view of a pull-on disposable diaper 1 (hereinafter, referred to as "diaper") according to a first embodiment. Fig. 2 is a schematic plan view of the diaper 1 in an unfolded and stretched state when viewed from the skin side. Fig. 3 is a schematic cross-sectional view taken along line AA in fig. 2. Fig. 4 is a schematic cross-sectional view taken along line BB in fig. 2.

Note that the stretched state of the diaper 1 is a state in which the diaper 1 has been stretched to such an extent that the wrinkles formed in the diaper 1 are substantially no longer visible. Specifically, the state is a state in which: the diaper 1 is stretched so that the lengths of its constituent members (e.g., skin-

side sheets

21 and 31 described later) match or are close to the sizes of their own members.

The diaper 1 has a vertical direction, a lateral direction and a thickness direction in a pants-type state, and also has a waist opening BH and a pair of leg openings LH. In the vertical direction, the waist side of the wearer is the upper side, and the crotch side of the wearer is the lower side. As shown in fig. 3 and 4, the thickness direction is a direction in which the members constituting the diaper 1 are superposed on each other. In the thickness direction, the side in contact with the wearer is the "skin side", and the opposite side is the "non-skin side".

The diaper 1 is a three-piece diaper including an absorbent main body 10 and a pair of belt members 20 and 30 (a pair of belt portions of the present invention), which are three rectangular members. Of the two

belt members

20 and 30, one positioned on the front side of the wearer is the front belt member 20, and one positioned on the rear side of the wearer is the rear belt member 30. In the developed state shown in fig. 2, the front belt member 20 and the back belt member 30 are arranged such that the longitudinal direction thereof coincides with the lateral direction of the diaper 1. In addition, the widthwise central portion of the front belt member 20 is disposed on the end portion of the absorbent main body 10 on one side in the longitudinal direction, and the widthwise central portion of the rear belt member 30 is disposed on the end portion of the absorbent main body 10 on the other side in the longitudinal direction.

In the diaper 1 in the unfolded state shown in fig. 2, the absorbent main body 10 is folded once at substantially the longitudinal center so that the longitudinal direction of the absorbent main body 10 coincides with the vertical direction of the diaper 1, and both lateral side portions of the front belt member 20 are joined to both lateral side portions of the rear belt member 30 by welding or the like, thereby obtaining the diaper 1 in the pants-type state shown in fig. 1.

The absorbent main body 10 includes an absorber 40, a top sheet 11 arranged on the skin side in the thickness direction with respect to the absorber 40, a back sheet 12 arranged on the non-skin side in the thickness direction with respect to the absorber 40, and an exterior sheet 13. The top sheet 11 is a liquid-permeable sheet, and is made of a hydrophilic spunbond nonwoven fabric, a hydrophilic breathable nonwoven fabric, or the like. The back sheet 12 is a liquid-impermeable sheet, and is made of a polyethylene film or the like. The outer sheet 13 is made of hydrophobic SMS nonwoven fabric or the like.

The top sheet 11 and the back sheet 12 have the same plane shape and size as the absorbent main body 10 in a view in the thickness direction, and cover the respective surfaces of the absorber 40. In addition, as shown in fig. 4, both lateral side portions of the outer sheet 13 are folded twice toward the skin side. The barrier cuff elastic member 14 (elastic string or the like) is fixed between the two layers of the outer sheet 13 formed by the first folded portion in a state stretched in the longitudinal direction. Since a part of the exterior sheet 13 is folded a second time on the skin side of the top sheet 11, the barrier cuff portion 15 capable of rising toward the skin side is formed.

The absorber 40 includes an absorbent core 41 that absorbs and retains excrement such as urine, and a core wrap sheet 42 that covers the absorbent core 41. The absorbent core 41 is formed of, for example, fibers having liquid absorbency such as pulp including Super Absorbent Polymer (SAP), which is formed into a predetermined shape (here, an hourglass shape). The core wrap sheet 42 is a liquid permeable sheet made of tissue, nonwoven fabric, or the like.

As shown in fig. 3, the front belt member 20 and the back belt member 30 have skin-

side sheets

21 and 31, non-skin-

side sheets

22 and 32, waist

elastic members

23 and 33, and covering

sheets

24 and 34, respectively. The sheet material constituting the front belt member 20 and the rear belt member 30 is a flexible sheet material made of SMS nonwoven fabric or the like. The waist

elastic members

23 and 33 may be string-like elastic members made of rubber, spandex, or the like, but may also be sheet-like elastic members made of stretchable nonwoven fabric, stretchable film, or the like.

The skin-

side sheets

21 and 31 and the non-skin-

side sheets

22 and 32 are arranged on the non-skin side in the thickness direction with respect to the absorbent main body 10. The waist

elastic members

23 and 33 are arranged side by side in the vertical direction between the skin-

side sheets

21 and 31 and the non-skin-

side sheets

22 and 32. In order to exhibit stretchability in the transverse direction, the waist

elastic members

23 and 33 are joined between the skin-

side sheets

21 and 31 and the non-skin-

side sheets

22 and 32 using an adhesive (e.g., a hot melt adhesive) in a state stretched in the transverse direction.

The

cover sheets

24 and 34 are shorter than the skin-

side sheets

21 and 31 and the non-skin-

side sheets

22 and 32 in the vertical direction. The covering

sheets

24 and 34 are arranged on the skin side in the thickness direction with respect to the absorbent main body 10, and cover the longitudinal ends of the absorbent main body 10.

Note that, although a three-piece diaper is given here as an example, the present invention is also applicable to a diaper having a portion connecting a pair of belt portions, i.e., a two-piece diaper in which the pair of belt portions are formed of a single member.

Joining of the

belt members

20 and 30 and the absorbent body 10

Fig. 5 is an explanatory diagram showing the amounts of the

adhesives

50 and 51 by which the

elastic members

23 and 33 are joined to the skin-

side sheets

21 and 31 and the non-skin-

side sheets

22 and 32. Fig. 6 is an explanatory view of the joining region 60 in which the

belt members

20 and 30 and the absorbent main body 10 are joined to each other.

As shown in fig. 3 and 6, the diaper 1 comprises a pair of joining regions 60 in which the non-skin side surfaces of both longitudinal end portions of the absorbent main body 10 are joined to the skin side surfaces of the

skin side sheets

21 and 31 of the

belt members

20 and 30 by an adhesive such as a hot melt adhesive. Therefore, the absorbent main body 10 and the pair of

belt members

20 and 30 are integrated.

For this reason, in the diaper 1, the lateral contraction force in the

belt members

20 and 30, i.e., the lateral contraction force of the waist

elastic members

23 and 33 is transmitted to the absorbent main body 10. It should be noted that if a large contraction force of the

elastic members

23 and 33 is transmitted to the absorbent main body 10, transverse gathers will be formed in the portions of the absorbent main body 10 that overlap the

belt members

20 and 30. This makes excrement more easily leak through the gap formed by the folds, and reduces comfort.

In view of this, in the diaper 1 of the present embodiment, the basis weight of the fibers of the skin-

side sheets

21 and 31 joined to the absorbent main body 10 is set to be higher than the basis weight of the fibers of the non-skin-

side sheets

22 and 32. For example, a configuration is possible in which the basis weight of the skin-

side sheets

21 and 31 is 15g/m²And the

non-skin side sheets

22 and 32 have a basis weight of 13g/m². Increasing the basis weight of the skin-

side sheets

21 and 31 increases the cushioning ability of the skin-

side sheets

21 and 31, and makes the contraction force of the waist

elastic members

23 and 33 more likely to be cushioned by the skin-

side sheets

21 and 31. Therefore, the contraction force of the waist

elastic members

23 and 33 is less likely to be transmitted to the absorbent main body 10.

In addition, as shown in fig. 5, since the basis weight of the

skin side sheets

21 and 31 is increased, the gaps between the fibers in the

skin side sheets

21 and 31 become smaller. Therefore, the adhesive 50 joining the

skin side sheets

21 and 31 to the waist

elastic members

23 and 33 is less likely to impregnate such gaps between the fibers. In other words, the adhesive is less likely to penetrate into the skin-

side sheets

21 and 31, and therefore, it is possible to suppress a situation in which the cushioning ability of the skin-

side sheets

21 and 31 is impaired by the rigidity of the adhesive 51.

Further, in the diaper 1 of the present embodiment, the amount per unit length (e.g., g/m) of the adhesive 50 joining the waist

elastic members

23 and 33 to the

side skin sheets

21 and 31 is lower than the amount per unit length (e.g., g/m) of the adhesive 51 joining the waist

elastic members

23 and 33 to the side

non-skin sheets

22 and 32. Therefore, this can further suppress a case where the cushioning ability of the skin-

side sheets

21 and 31 is impaired by the rigidity of the adhesive 50.

In other words, in the diaper 1 of the present embodiment, the amount of the adhesive 50 joining the waist

elastic members

23 and 33 to the skin-

side sheets

21 and 31 is reduced, and therefore the joining strength between the skin-

side sheets

21 and 31 and the waist

elastic members

23 and 33 is lower than the joining strength between the non-skin-

side sheets

22 and 32 and the waist

elastic members

23 and 33.

As described above, in the diaper 1 of the present embodiment, the cushioning ability of the skin-

side sheets

21 and 31 is high, and the cushioning ability is less likely to be impaired by the adhesive 50, and therefore the contraction force of the waist

elastic members

23 and 33 can be cushioned by the skin-

side sheets

21 and 31. Therefore, the absorbent main body 10 is less likely to be affected by the contraction of the

belt members

20 and 30, and wrinkles are less likely to be formed in the absorbent main body 10. Therefore, the close fit between the absorbent main body 10 and the wearer is improved, leakage of excrement is suppressed, and the comfort is also improved.

In addition, the

skin side sheets

21 and 31 are in direct contact with the wearer. For this reason, reducing the amount of the adhesive 50 on the side corresponding to the skin-

side sheets

21 and 31 makes it possible to suppress the rigidity of the skin-

side sheets

21 and 31 and also improve the texture of the

belt members

20 and 30.

In addition, in the case where the skin-

side sheets

21 and 31 are made of a layered nonwoven fabric, it is desirable that the basis weight of the layer on the non-skin side (the layer on the side corresponding to the waist elastic members 23 and 33) is higher than the basis weight of the layer on the skin side. For example, in the case where the skin-

side sheets

21 and 31 are made of SMS nonwoven fabric (spunbond/meltblown/spunbond nonwoven fabric), the following configuration is desired: the basis weight of the S layer on the skin side was 4.5g/m²The basis weight of the M layer was 1.5g/M²And the basis weight of the S layer on the non-skin side is 9g/m². According to this configuration, the adhesive 50 is less likely to be impregnated even into the skin-

side sheets

21 and 31, the cushioning ability of the skin-

side sheets

21 and 31 is less likely to be impaired by the adhesive 50, and the absorbent main body 10 is less likely to be affected by the contraction of the

belt members

20 and 30.

Note that, in the diaper 1 of the present embodiment, instead of applying the adhesive to the skin-

side sheets

21 and 31 and the non-skin-

side sheets

22 and 32, the

adhesives

50 and 51 are applied directly to the waist

elastic members

23 and 33 by, for example, V-groove application. The positions of the

adhesives

50 and 51 and the positions of the waist

elastic members

23 and 33 are adjusted in the V-groove coating so that a larger amount of the adhesive 51 is applied to the portions of the waist

elastic members

23 and 33 to be joined to the

non-skin side sheets

22 and 32. According to this configuration, the amount per unit length of the adhesive 50 joining the waist

elastic members

23 and 33 to the skin-

side sheets

21 and 31 can be set smaller than the amount per unit length of the adhesive 51 joining the waist

elastic members

23 and 33 to the non-skin-

side sheets

22 and 32.

In addition, the basis weights (masses per unit area) of the fibers of the skin-

side sheets

21 and 31 and the non-skin-

side sheets

22 and 32 can be compared using a known method. For example, the skin-

side sheets

21 and 31 and the non-skin-

side sheets

22 and 32 are separated from the

belt members

20 and 30 of the target diaper 1, and appropriately sized areas of the sheets are cut out to obtain samples of the skin-

side sheets

21 and 31 and samples of the non-skin-

side sheets

22 and 32. It is sufficient that: the mass and area of the sample are then measured, the mass per unit area is calculated, and the results are compared.

In addition, a known method can be used to compare the amount per unit length of the adhesive 50 joining the waist

elastic members

23 and 33 to the skin-

side sheets

21 and 31 with the amount per unit length of the adhesive 51 joining the waist

elastic members

23 and 33 to the non-skin-

side sheets

22 and 32. For example, appropriately sized areas of the

belt members

20 and 30 of the objective diaper 1 are cut out to obtain a sample, and a liquid such as ink for visualizing the

adhesives

50 and 51 is applied to the skin-side surface and the non-skin surface of the sample. An electron microscope is then used to capture magnified images of sections of the waist

elastic members

23 and 33 taken along the longitudinal direction and the direction orthogonal thereto. Then it is sufficient that: the amount of the adhesive 50 on the skin-

side sheets

21 and 31 is visually compared with the amount of the adhesive 51 on the non-skin-

side sheets

22 and 32, or is compared after calculating the area thereof.

In addition, the fact that the joining strength between the

skin side sheets

21 and 31 and the waist

elastic members

23 and 33 is weaker than the joining strength between the

non-skin side sheets

22 and 32 and the waist

elastic members

23 and 33 can be confirmed using a tensile tester. Specifically, two samples, each of which is elongated in the lengthwise direction of the waist

elastic members

23 and 33 and includes one waist

elastic member

23 or 33, are taken from the

belt members

20 and 30 of the objective diaper 1. The

non-skin side sheet

22 or 32 was separated from one of the samples to produce a sample in which the waist

elastic member

23 or 33 was joined to the

skin side sheet

21 or 31, and the

skin side sheet

21 or 31 was separated from the other sample to produce a sample in which the waist

elastic member

23 or 33 was joined to the

non-skin side sheet

22 or 32. Then, for each sample, a sheet (skin-

side sheet

21 or 31, or non-skin-side sheet 22 or 32) was attached to one end of a chuck of a tensile tester, and a waist

elastic member

23 or 33 was attached to the other end of the chuck such that the longitudinal direction of the waist

elastic member

23 or 33 coincides with the pulling direction. The sample is then pulled at a predetermined speed (e.g., 300mm/min) until the sheet and waist

elastic member

23 or 33 are pulled apart. The stress at this time (maximum stress, average stress, etc.) is then used as the joining strength between the sheet and the waist

elastic member

23 or 33 for comparison.

Joining region 60

Fig. 7A is an explanatory view of the first application region 64 in which the adhesive is applied to the

belt members

20 and 30, and fig. 7B is an explanatory view of the second application region 65 in which the adhesive is applied to the absorbent main body 10. In the diaper 1 of the present embodiment, the joint region 60 (fig. 6) is formed by the overlap of the first coated region 64 (fig. 7A) and the second coated region 65 (fig. 7B). Note that, in the following description, the joining region 60 located on the front side of the wearer will also be referred to as a front joining region 61, and the joining region 60 located on the rear side of the wearer will also be referred to as a rear joining region 62.

More specifically, the first application region 64 is a region in which the adhesive is applied to the skin-side surfaces of the skin-

side sheets

21 and 31 of the

belt members

20 and 30, and is a rectangular region elongated in the transverse direction of the diaper 1 as shown in fig. 7A. In the rear belt member 30, a plurality of (here, six) first coated regions 64 are arranged side by side in the vertical direction of the diaper 1 with very small gaps therebetween. In the front belt member 20, three first coated regions 64 are arranged side by side in the vertical direction. It should be noted that the gap between the top two first coated regions 641 and 642 is very small, while the gap between the top second first coated region 642 and the third first coated region 643 is larger. Note that "a very small gap" means a gap smaller than a gap between the waist

elastic members

23 and 33 juxtaposed in the vertical direction.

The second application region 65 is a region where the adhesive is applied to the non-skin-side surface of the absorbent main body 10, and is a rectangular region elongated in the vertical direction of the diaper 1 as shown in fig. 7B. In the end portion on the rear side of the absorbent main body 10, a plurality of (here, seven) second coated regions 65, which have no gaps or very small gaps between them, are arranged side by side in the transverse direction of the diaper 1. Also in the end portion on the front side of the absorbent main body 10, a plurality of (here, seven) second coating regions 65, which have no gap or a very small gap therebetween, are arranged side by side in the lateral direction. It should be noted that the vertical length of the second coating regions 651 at both lateral ends on the front side is equal to the length of the second coating region 65 on the rear side, while the vertical length of the second coating region 652 in the middle portion on the front side is shorter than the vertical length of the second coating region 65 on the rear side and is arranged closer to the ends of the absorbent main body 10.

For this reason, as shown in fig. 6, since the first coating region 64 and the second coating region 65 overlap, the rear joint region 62 has a substantially rectangular outer shape, and substantially the entire rear joint region 62 is a joint region where the absorbent main body 10 is joined to the

belt members

20, 30.

On the other hand, since the first coating region 64 and the second coating region 65 overlap, the front joining region 61 has a substantially rectangular outer shape, and the front joining region 61 includes a substantially rectangular region where no adhesive is coated. In other words, the front joining zone 61 includes: a pair of first regions 61A elongated in the transverse direction; and a pair of second regions 61B elongated in the vertical direction and connecting the lateral ends of the pair of first regions 61A. Also, in addition, there are provided regions where no adhesive is applied at positions between the pair of first regions 61A and between the pair of second regions 61B, that is, non-joined regions 63 where the absorbent main body 10 is not joined to the skin-

side sheets

21 and 31.

Since the non-joining region 63 is provided in this way, the size of the joining region 60 joining the absorbent main body 10 and the

belt member

20 or 30 is reduced, and the absorbent main body 10 is less likely to be affected by the contraction of the

belt members

20 and 30. In addition, the upper end portions of the absorbent main body 10 are joined to the

belt members

20 and 30 through the upper first region 61a1, and the lower end portions of the

belt members

20 and 30 are joined to the absorbent main body 10 through the lower first region 61a 2. Therefore, in the diaper 1, the upper end portion of the absorbent main body 10 is prevented from being rolled up from the lower end portions of the

belt members

20 and 30, and the provision of the non-joined region 63 therebetween suppresses the formation of wrinkles in the absorbent main body 10.

In addition, if the joining region 60 includes only the pair of first regions 61A, when the wearer grasps the

belt members

20 and 30 and pulls up the diaper 1, the absorbent main body 10 will bend in the non-joining region 63, making it difficult to pull up the absorbent main body 10. To solve this problem, the diaper 1 of the present embodiment includes the pair of second regions 61B connecting the pair of first regions 61A. For this reason, due to the second region 61B continuing in the vertical direction of the diaper 1, the pull-up force is easily transmitted from the

belt members

20 and 30 to the absorbent main body 10, and the absorbent main body 10 can be safely pulled up. In addition, since the second regions 61B are arranged at the lateral ends of the first regions 61A, the absorbent main body 10 is less likely to become twisted, and can be pulled up while maintaining the wide state, thereby appropriately eliminating the gap between the absorbent main body 10 and the wearer.

In addition, as shown in fig. 6, in the front and rear joint regions 60(61 and 62), the widthwise end portions thereof (the second region 61B in the front joint region 61) overlap with the longitudinal end portions of the barrier cuff elastic member 14. For this reason, the pull-up force is easily transmitted from the

belt members

20 and 30 to the elastic member 14, and the entire absorbent main body 10 is easily pulled up in coordination with the lifting of the elastic member 14. Note that only the effective length portion of the elastic member 14 exhibiting stretchability is shown in the drawings. As shown, it is desirable that the landing zone 60 partially overlaps the effective length of the elastic member 14.

In addition, in the front bonding region 61, a lower end 61Bb of the second region 61B is located lower than a lower end 61Ab of the first region 61A excluding the second region 61B. For this reason, in the widthwise central portion of the front joint region 61, the vertical length thereof is small, and the contraction of the band portion 20 is less likely to be affected. In the lateral end portions of the front joining region 61, the portions overlapping the elastic members 14 are longer, and the absorbent main body 10 is more easily pulled up.

Note that the adhesive may be applied to the entire first and second

coated regions

64 and 65, or the adhesive may be applied only to some portions. Examples of the partial adhesive coating pattern include a line-shaped coating pattern having a spiral line or the like, and a pattern of alignment points or the like. It is assumed that in the first application region 64 the adhesive is applied continuously or with very little clearance in between in the transverse direction of the diaper 1 and that in the second application region 65 the adhesive is applied continuously or with very little clearance in between in the vertical direction of the diaper 1.

In addition, as shown in fig. 6, with respect to the vertical direction of the diaper 1, it is preferable that the length L2 of the non-joined region 63 be greater than the length L1 of the lower first region 61A2 of the pair of first regions 61A (L1< L2). According to this configuration, the size of the non-joining region 63 is large, and the size of the joining region 60 between the absorbent main body 10 and the

belt member

20 or 30 is small, and therefore the absorbent main body 10 is less likely to be affected even by the contraction of the

belt members

20 and 30. Therefore, the formation of wrinkles in the absorbent main body 10 can be further suppressed. Further, even if the lower end portions of the

belt members

20 and 30 become rolled up, their influence on the comfort is small, and therefore, it is less likely that a problem occurs even if the vertical length L1 of the lower first region 61a2 is set shorter.

Similarly, with respect to the transverse direction of the diaper 1, it is preferable that the length L5 of the non-joined region 63 is greater than the length L4 of the second region 61B. In fig. 6, the length L5 of the non-joined region 63 is approximately 5 times the length L4 of the second region 61B. According to this configuration, the absorbent main body 10 is less likely to be affected even by the contraction of the

belt members

20 and 30.

In addition, with respect to the vertical direction of the diaper 1, it is preferable that the length L3 of the upper first region 61a1 is greater than the length L1 of the lower first region 61a2 (L1< L3). For example, if the upper end portion of the absorbent main body 10 becomes rolled up, the comfort will be greatly affected by the formation of the height difference in the diaper 1. For this reason, by increasing the vertical length L3 of the upper first region 61a1 and firmly joining the upper end portion of the absorbent main body 10 to the

belt members

20 and 30, a decrease in the comfort can be prevented. In other words, since the vertical length L1 of the lower first region 61a2 is not greater than the vertical length of the upper first region 61a1, the size of the non-joined region 63 can be increased, and the absorbent main body 10 is less likely to be affected even by the contraction of the

belt members

20 and 30.

In addition, although the non-joined region 63 is provided only in the front joined region 61 in the diaper 1 of the present embodiment, it is not limited thereto. The non-joined region may also be provided at the center of the rear joined region 62. Instead, a configuration is possible in which the non-joining region 63 is not provided in the front joining region 61 and the non-joining region is provided only in the rear joining region 62.

It should be noted that, when the wearer sleeps or sits, the rear belt member 30 is more likely to be rubbed and sandwiched between the wearer and the floor, the chair, or the like, and thus the rear belt member 30 is more likely to become separated from the absorbent main body 10, as compared with the front belt member 20. In view of this, it is sufficient that: as in the diaper 1 of the present embodiment, the non-joined region 63 is provided in the front joined region 61 and the non-joined region is not provided in the rear joined region 62 (note that the non-joined region is a relatively large region, i.e., a region having a length in the lateral direction and the vertical direction larger than the gap between the waist elastic members 33, for example). According to this configuration, separation of the rear belt member 30 and the absorbent main body 10 is prevented, and the absorbent main body 10 is less likely to be affected even by contraction of the front belt member 20.

In addition, the front joining zone 61 is located at the center of the wearer's abdominal region, which is a region that expands and contracts during breathing. For this reason, providing the non-joined region 63 in the front joined region 61 makes it possible to minimize the rigidity of the belt member 20 that is in contact with the central portion of the abdominal region of the wearer, and to reduce discomfort during breathing.

In addition, as shown in fig. 7B, non-coated regions 66, to which no adhesive is applied, are provided on the front and rear sides of the absorbent main body 10 at positions between each of the second coated regions 651 located at both lateral end portions and the second coated region 652 located between the second coated regions 651. For this reason, as shown in fig. 6, at the transverse position P corresponding to the non-coating region 66 in the front and rear joining regions 60(61 and 62), no adhesive is applied, or adhesive is applied only on the

belt members

20 and 30 sides. Therefore, at the position P in the joining region 60, the amount of applied adhesive is smaller than that in the laterally adjacent region, and the rigidity is lower, so these positions may become folding points in the

belt members

20 and 30. Accordingly, the

belt members

20 and 30 can be curved in conformity with the waist of the wearer, thereby improving comfort. In particular, the ability of the front belt member 20 to flex readily makes it possible to further reduce discomfort during breathing, given that the abdominal region expands and contracts during breathing.

In addition, the waist

elastic members

23 and 33 that do not overlap the joint region 60 in a view along the thickness direction of the diaper 1 may contract in the lateral direction more easily than the waist

elastic members

23 and 33 that overlap the joint region 60. For this reason, in the waist elastic member overlapping the absorbent main body 10, if some portions thereof (23 a to 23i and 33a to 33i in fig. 6) overlap the joint region 60, and if other portions do not overlap the joint region 60, the

belt members

20 and 30 will locally contract at some positions, and the

belt members

20 and 30 will likely become twisted.

In view of this, as shown in fig. 6, it is preferable that all the waist elastic members (the waist elastic members 23a to 23i and 33a to 33i) overlapping the absorbent main body 10 in the thickness direction overlap the joint region 60 in the thickness direction. In other words, it is preferable that the upper end 60a of the joining region 60 is located at the same position as or higher than the uppermost waist

elastic members

23a and 33a overlapping the absorbent main body 10, and the lower end 60b of the joining region 60 is located at the same position as or lower than the lowermost waist

elastic members

23i and 33i overlapping the absorbent main body 10, with respect to the vertical direction of the diaper 1. According to this configuration, twisting due to local contraction in the

belt members

20 and 30 can be prevented, and the waist of the wearer can be securely covered. Deterioration in appearance and discomfort can also be prevented when the diaper is worn.

In addition, as shown in fig. 3, the thickness of the absorber 40 may be set differently in the portions 40A to 40C in the longitudinal direction of the absorber 40. For example, it is desirable that the thickness T1 of the front portion 40A of the absorber 40 located on the front side of the wearer and the thickness T3 of the rear portion 40C of the absorber 40 located on the rear side of the wearer be greater than the thickness T2 of the crotch portion 40B of the absorber 40 located at the crotch region of the wearer (T2< T1, T3). According to this configuration, the portions of the absorbent main body 10 that overlap with the

belt members

20 and 30 in the thickness direction are thicker and have higher rigidity, and therefore the formation of wrinkles in the absorbent main body 10 due to contraction of the

belt members

20 and 30 can be suppressed. By suppressing the formation of wrinkles in the skin-side surface of the absorbent main body 10 in this way, it is possible to suppress a situation in which excrement flows along such wrinkles and leaks.

In particular, in the case of the diaper 1 of the present embodiment, the rear joining region 62 has no non-joining region, and therefore it is desirable that the thickness T3 of the rear portion 40B of the absorber 40 be greater than the thickness T1 of the front portion 40A of the absorber 40 (T2< T1< T3). According to this configuration, higher rigidity is achieved in the rear end of the absorbent main body 10, which is more likely to be affected by the belt member 30 than the front end of the absorbent main body 10. Therefore, the formation of wrinkles in the absorbent main body 10 due to the contraction of the belt member 30 can be more reliably suppressed.

Note that the thickness of the absorber 40 may be compared using a known method. For example, the absorber 40 may be separated from the target diaper 1 using a dial gauge (ID-C1012C) manufactured by Sanfeng corporation or an equivalent thereof at an appropriate contact pressure (e.g., 3 gf/cm)²) The thicknesses of the target portions 40A to 40C of the absorber 40 were pressed down and measured, and then compared. Alternatively, the comparison may be made visually or using a captured image of a cross section of the absorber 40 taken in the longitudinal direction.

In the second embodiment, the present invention is not limited to the first embodiment

Fig. 8 is an explanatory view of a joint region 60 of the diaper 1 according to the second embodiment. In the diaper 1 of the second embodiment, the back belt member 30 has a protruding region 70 which protrudes farther downward than the front belt member 20. The lateral side ends 70a of the protruding areas 70 are inclined inward in the lateral direction while extending downward in the vertical direction. The hip area of the wearer is covered by the protruding area 70. In addition, the front belt member 20 and the back belt member 30 have different shapes, and thus the diaper 1 can be prevented from being worn reversely.

In the rear belt member 30 of the second embodiment, a plurality of (here, three) elastic members 71 extending along the lower end portions of the protruding regions 70 are arranged side by side in the vertical direction, except for the waist elastic member 33 extending in the lateral direction. Similarly to the waist elastic member 33, an adhesive is used to join the elastic members 71 of the protruding regions 70 (hereinafter referred to as protruding region elastic members 71) between the skin-side sheet 31 and the non-skin-side sheet 32 so as to be stretchable and contractible in the transverse direction.

In addition, of the elastic members 33 and 71 of the back belt member 30, it is desirable that all of the waist elastic members 33a to 33i and the protruding region elastic members 71a to 71c overlapping the absorbent main body 10 in the thickness direction overlap the back joint region 62 in the thickness direction. According to this configuration, twisting due to local contraction of the back belt member 30 can be prevented, and the waist and hip regions of the wearer can be securely covered.

In addition, it is preferable that the lateral lengths L6 and L7 of the lower portion 62A of the rear joint region 62 overlapping the protrusion region elastic members 71a to 71c in the thickness direction be smaller than the lateral length L8 of the upper portion 62B of the rear joint region 62 overlapping the waist elastic members 33a to 33i in the thickness direction (L6, L7< L8).

Further, it is preferable that, among the protruding region elastic members 71a to 71c, the lateral length L6 of the portion of the rear joining region 62 overlapping with the lower elastic members 71b and 71c in the thickness direction is smaller than the lateral length L7 of the portion of the rear joining region 62 overlapping with the upper protruding region elastic member 71a in the thickness direction (L6< L7). In addition, it is preferable that the lower portion 62A of the rear joint region 62 does not intersect the outer contour of the absorbent core 41, that is, it is preferable that the lower portion 62A does not protrude outward beyond the absorbent core 41 in the lateral direction.

According to this configuration, in the diaper 1 of the second embodiment, the back belt member 30 is large, but the back joint region 62 may be set as small as possible, and the size of the region where the back belt member 30 and the absorbent main body 10 are not joined may also be increased. According to this configuration, the absorbent main body 10 is less likely to be affected by the contraction of the back belt member 30, and it is possible to suppress the formation of wrinkles in the absorbent main body 10 and suppress leakage of excrement. In addition, even if the lower end portion of the rear belt member 30 becomes rolled up, the influence on the comfort is small, and therefore, the problem is unlikely to occur even if the lateral length of the lower portion of the rear joint region 62 is reduced. In other words, even if the lower end portion of the back belt member 30 becomes rolled up, the lateral length of the upper portion of the back joining region 62 is long, and the upper portion of the back belt member 30 is firmly joined to the absorbent main body 10, so that further separation of the back belt member 30 and the absorbent main body 10 can be prevented.

In addition, the absorbent core 41 shown in fig. 8 has an hourglass shape in which the longitudinal central portion is contracted inward in the width direction. In this case, both lateral side portions of the absorbent main body 10 may rise to the skin side along the lateral side of the absorbent core 41 by being sandwiched between the legs of the wearer. For this reason, as described above, it is desirable that the lateral length of the rear joint region 62 also decreases toward the longitudinal center in a stepwise manner in accordance with the narrowing of the absorbent core 41. According to this configuration, it is possible to prevent the protruding area 70 from penetrating inward in the lateral direction together with the two lateral side portions of the absorbent main body 10 that rise as a result of being sandwiched between the legs of the wearer, thereby maintaining the state in which the protruding area 70 covers the hip area.

Other embodiments

Although embodiments of the present disclosure have been described above, the above-described embodiments of the present disclosure are merely to facilitate understanding of the present disclosure, and are not to be construed as limiting the present disclosure in any way. The present disclosure may make various changes or modifications without departing from the spirit thereof, and encompasses equivalents thereof.

List of reference numerals

1 diaper (underpants type absorbent article), BH waist opening, LH leg opening,

10 an absorbent main body, 11 a top sheet, 12 a back sheet, 13 an outer sheet,

14 barrier cuff portion elastic member, 15 barrier cuff portion,

20 front belt member (belt portion), 21 skin-side sheet, 22 non-skin-side sheet,

23 waist elastic member, 24 cover sheet,

30 back belt member (belt portion), 31 skin side sheet, 32 non-skin side sheet,

33 waist elastic member (elastic member), 34 cover sheet,

40 absorbers, 41 absorbent cores, 42 core wrapping sheets,

50 adhesive, 51 adhesive,

60 bonding region, 61 front bonding region, 61A first region,

61B second region, 62 post-bonding region, 63 non-bonding region,

64 first coating region, 65 second coating region,

70 projected area, 71 projected area elastic member (elastic member).

Claims

1. A pants-type absorbent article having a vertical direction, a lateral direction and a thickness direction,

the pants-type absorbent article includes:

a pair of band portions extending in the transverse direction,

each of the band portions includes:

a skin-side sheet;

a non-skin side sheet; and

the skin-side sheet having a fiber basis weight greater than that of the non-skin-side sheet, the elastic member being joined to the skin-side sheet by an amount per unit length of adhesive less than the amount per unit length of adhesive joining the elastic member to the non-skin-side sheet,

at least one of the pair of engagement regions comprises:

a pair of first regions elongated in the transverse direction; and

the non-joined region where the absorbent main body is not joined to the skin-side sheet is disposed at a position between the pair of first regions and between the pair of second regions.

2. The pant-type absorbent article according to claim 1, wherein:

3. The pant-type absorbent article according to claim 1 or 2, wherein:

4. The pant-type absorbent article according to claim 1, wherein:

in the region of the pair of joining regions,

5. The pant-type absorbent article according to claim 1, wherein:

in each of the band portions, a first end of the band portion,

6. The pant-type absorbent article according to claim 1, wherein:

7. The pant-type absorbent article according to claim 6, wherein:

among the plurality of elastic members arranged in the protruding region,

8. The pant-type absorbent article according to claim 1, wherein:

the absorbent main body has an absorber, and