WO2020217688A1

WO2020217688A1 - Absorbent article

Info

Publication number: WO2020217688A1
Application number: PCT/JP2020/007213
Authority: WO
Inventors: 裕樹合田; 章恵木下
Original assignee: ユニ・チャーム株式会社
Priority date: 2019-04-26
Filing date: 2020-02-21
Publication date: 2020-10-29
Also published as: JP7145810B2; BR112021020626A2; CN113710211A; CN113710211B; JP2020182542A

Abstract

The present disclosure provides an absorbent article that is capable of suppressing condensation on an outer side of the absorbent article while decreasing the temperature and the absolute humidity on an inner side of the absorbent article. An absorbent article (1) according to the present disclosure includes an absorption core (12a), a diffusion sheet (12d), and a moisture-permeable back sheet (13) laminated in this order from a side that faces the skin toward a side that does not face the skin, wherein the absorption core (12a) is mainly formed from a superabsorbent polymer, the diffusion sheet (13) is mainly formed from hydrophilic fibers and has a Klemm water absorption of 100 mm or greater, and the moisture-permeable back sheet (13) has a moisture permeability of 1500 g/m²/24h or greater.

Description

Absorbent article

This disclosure relates to absorbent articles.

For absorbent articles such as sanitary napkins, panty liners, and diapers, it is desired to improve the comfort of the wearer.

Patent Document 1 is configured to include a hydrophilized hydrophobic material, has a plurality of through holes penetrating in the thickness direction formed in a portion located in a region facing the excretion portion, and has a plurality of absorbers. It has a structure in which layers are laminated, and the lower layer closest to the back sheet has a higher Krem water absorption height than the upper layer closest to the front sheet, and the back sheet has a large number of micropores and is moisture permeable. It is configured to include a film, and a water-repellent portion is formed on a portion of the moisture-permeable film located in the area facing the excretion part on the surface facing the skin to form a water-repellent part. Disclosed are absorbent articles in which the ratio of the total area of the water-repellent portion is 30% or more and 60% or less.

According to Patent Document 1, the absorbent article having such a structure has an excellent dry feeling on the surface facing the skin, and the liquid does not easily seep out from the back sheet.

JP-A-2015-37479

In absorbent articles such as sanitary napkins, panty liners, and diapers, high temperature and / or high absolute humidity inside the absorbent article, that is, between the absorbent article and the skin, causes the wearer to feel hot. In addition, the wearer's skin may become stuffy or rash, and the comfort may deteriorate.

As a means for solving such a problem, it is conceivable to make the excrement liquid easily transpire to the outside of the absorbent article after excretion, for example, after urination. However, when the amount of excrement liquid that evaporates to the outside of the absorbent article is increased, for example, through the back sheet or the like, dew condensation occurs on the back sheet or the like of the absorbent article, and the outside of the absorbent article gets wet. May occur. In this regard, the absorbent article disclosed in Patent Document 1 is intended to suppress the dry feeling of the surface facing the skin and the exudation of the liquid from the back surface sheet, but the excrement liquid evaporated to the outside of the absorbent article. It lacked the viewpoint of suppressing dew condensation.

An object of the present disclosure is to provide an absorbent article capable of suppressing dew condensation on the outside of the absorbent article while lowering the temperature and absolute humidity inside the absorbent article.

The Discloser has found that the above issues can be achieved by the following means:

<< Aspect 1 >>
An absorbent article in which the absorbent core, the diffusion sheet, and the breathable back sheet are laminated in this order from the skin facing surface side to the skin non-facing surface side.
The absorption core is mainly composed of a super absorbent polymer.
The diffusion sheet is mainly composed of hydrophilic fibers and has a Krem water absorption of 100 mm or more, and the moisture-permeable back sheet has a moisture permeability of 1500 g / m ² / 24h or more.
Absorbent article.

Super absorbent polymers are considered to retain water in excrement more slowly than pulp and the like. This is because the water retention by pulp etc. depends on the physical properties of the fiber such as the capillary phenomenon of the fiber, whereas the water retention of the excrement liquid by the superabsorbent polymer is the water retention between the superabsorbent polymer and the water in the excrement liquid. It is considered that this is due to a chemical reaction or the like.

Therefore, in an absorbent article using a superabsorbent polymer as a component of the absorption core, as a means for enhancing the water retention by the superabsorbent polymer, for example, the main component of the absorption core is made of pulp or the like, and the excrement is temporarily discharged by the pulp. In other words, it is conceivable to retain water in a state where it can be discharged, and then gradually absorb and retain the excrement liquid retained by pulp or the like with a super absorbent polymer.

However, when the excrement is retained for a long time in a state where pulp or the like can be discharged inside the absorbent article, the temperature and absolute humidity inside the absorbent article, that is, between the absorbent article and the skin are increased. The height may increase, which may cause stuffiness or rash on the wearer's skin, which may make the wearer uncomfortable to wear. In order to reduce such stuffiness and rashes, the excrement liquid inside the absorbent article is evaporated from the back sheet side of the absorbent article, for example, to lower the temperature and absolute humidity inside the absorbent article. Can be considered. However, when the excrement liquid inside the absorbent article is evaporated, dew condensation may occur on the non-skin facing surface side of the moisture permeable back sheet.

The absorbent article according to the first aspect of the present disclosure uses an absorbent core mainly made of a super absorbent polymer to reduce temporary water retention of excrement by the absorbent core, that is, water retention that can be discharged. Then, the excrement liquid that has not been retained by the superabsorbent polymer and has flowed to the non-skin facing surface side of the absorption core is diffused in the in-plane direction of the absorbent article by the diffusion sheet. As a result, the area in which the excrement liquid comes into contact with the moisture-permeable backsheet is increased, the water in the excrement liquid is efficiently evaporated from the moisture-permeable backsheet, and the amount of evaporation per unit area of the moisture-permeable backsheet is reduced. .. In addition, the area of the superabsorbent polymer in contact with the excrement liquid also increases, so that the superabsorbent polymer more easily absorbs and retains the excrement liquid. Therefore, the absorbent article according to the first aspect of the present disclosure can reduce dew condensation on the non-skin facing surface side of the moisture permeable backsheet while lowering the temperature and absolute humidity inside the absorbent article.

<< Aspect 2 >>
The absorbent article according to aspect 1, wherein the moisture permeable back sheet has a moisture permeability of 3500 g / m ² / 24h or less.

In the absorbent article according to the second aspect of the present disclosure, the moisture permeability of the moisture permeable backsheet is below a certain level, so that dew condensation on the non-skin facing surface side of the moisture permeable backsheet is further suppressed. Thereby, the absorbent article according to the second aspect of the present disclosure can reduce the absolute humidity between the wearer's clothes (for example, underwear) and the skin, and is worn after excretion, for example, after urination. The absolute humidity between a person's clothes, such as underwear, and the skin is maintained within an appropriate range, and the comfort can be further improved.

<< Aspect 3 >>
The absorbent article according to aspect 1 or 2, wherein the diffusion sheet does not substantially contain a surfactant.

In the absorbent article according to aspect 3 of the present disclosure, the diffusion sheet does not substantially contain a surfactant. Therefore, the absorbent article according to the third aspect of the present disclosure can suppress a decrease in the surface tension of the excrement liquid due to the mixing of the surfactant in the excrement liquid, and the liquid from the moisture permeable back sheet. Leakage can be further suppressed.

<< Aspect 4 >>
The absorbent article according to any one of aspects 1 to 3, wherein the diffusion sheet has a hydrophilic fiber basis weight of 35 g / m ² or more and a Krem water absorption of 130 mm or more.

In the absorbent article according to the fourth aspect of the present disclosure, the hydrophilic fiber contained in the diffusion sheet has a basis weight of a certain amount or more and a Krem water absorption degree of a certain amount or more, so that the diffusivity of the excrement liquid by the diffusion sheet is high. Is high. Therefore, the absorbent article according to the fourth aspect of the present disclosure can further improve the water retention by the superabsorbent polymer in the absorption core, and the amount of water vaporized from the moisture-permeable backsheet in the excrement liquid can be increased. Can be increased more.

<< Aspect 5 >>
The absorbent article according to any one of aspects 1 to 4, wherein the hydrophilic fibers include rayon fibers having streaks on the surface along the direction in which the fibers extend.

In the absorbent article according to the fifth aspect of the present disclosure, the hydrophilic fibers contained in the diffusion sheet contain rayon fibers having streaks on the surface along the direction in which the fibers extend. Rayon fibers having streaks on the surface along the direction in which the fibers extend tend to diffuse excrement along the direction in which the fibers extend due to the capillary force of the grooves of the muscles. Therefore, the absorbent article according to the fifth aspect of the present disclosure has high diffusibility of the excrement liquid by the diffusion sheet, can further improve the water retention by the super absorbent polymer in the absorption core, and is in the excrement liquid. The amount of moisture evaporated from the moisture permeable backsheet can be further increased.

<< Aspect 6 >>
The absorbent article has a longitudinal direction and a width direction.
The absorbent article according to any one of aspects 1 to 5, wherein the diffusion sheet covers at least a part of at least one end of the absorption core in the longitudinal direction and the width direction.

After excretion, the excrement fluid may flow to the inner end of the absorbent article and accumulate due to the movement of the wearer's body. In particular, when the excrement fluid collects at the longitudinal end of the absorbent article, i.e. the front and back sides of the absorbent article, and / or the widthwise end, i.e. the lateral side of the absorbent article, the excretory fluid leaks forward. , Post-leakage, and / or lateral leakage may occur. In the absorbent article according to aspect 6 of the present disclosure, since the diffusion sheet covers at least a part of at least one end of the absorbent layer in the longitudinal direction and the width direction, the front side and the rear side of the absorbent article. And / or the excrement fluid that has flowed laterally is likely to diffuse in the in-plane direction of the absorbent article. Thereby, in the absorbent article according to the sixth aspect of the present disclosure, the bias of the excretory liquid inside the absorbent article can be suppressed, and the front leakage, the rear leakage, and / or the lateral leakage of the excretion liquid can be suppressed. it can.

<< Aspect 7 >>
It has an absorbent core and an absorber having a core wrap sheet covering at least the skin non-opposing surface side of the absorbent core, and the diffusion sheet is the core wrap sheet.
The absorbent article according to any one of aspects 1 to 6.

In the absorbent article according to aspect 7 of the present disclosure, since the diffusion sheet constitutes the core wrap sheet, a separate member for diffusing the excrement is not required, and the thickness of the absorbent article is reduced. can do. Further, in the absorbent article according to the seventh aspect of the present disclosure, since the diffusion sheet directly receives and diffuses the excrement liquid flowing out from the absorption core, the excrement liquid is discharged in the in-plane direction of the absorbent article in a shorter time. It can be diffused. In addition, in the absorbent article according to the seventh aspect of the present disclosure, since the diffusion sheet is in contact with the absorption core, the absorption core easily absorbs the excrement liquid diffused by the diffusion sheet.

<< Aspect 8 >>
The absorbent article according to aspect 7, wherein the bonding area between the diffusion sheet and the moisture permeable back sheet is more than 0.5% and 20.0% or less of the area of the diffusion sheet.

When the diffusion sheet is bonded to the moisture permeable back sheet by, for example, adhesion by adhesive, adhesion by heat fusion, etc., such a bonded portion has low diffusibility of excrement liquid. In the absorbent article according to the eighth aspect of the present disclosure, since the bonding area between the diffusion sheet and the moisture-permeable back sheet is within a certain range, it is possible to improve the diffusivity while maintaining the bonding.

<< Aspect 9 >>
An intermediate sheet having a lower hydrophilicity than the diffusion sheet and having a dynamic wetting index of more than 0.0 seconds and 0.2 seconds or less is laminated between the diffusion sheet and the moisture permeable back sheet. , The absorbent article according to aspect 7.

In the absorbent article according to the ninth aspect of the present disclosure, an intermediate sheet having hydrophilicity but difficult to retain water in the excrement liquid is interposed between the diffusion sheet and the moisture permeable back sheet, whereby evaporation by the moisture permeable back sheet is performed. The amount of wetness of the moisture-permeable back sheet can be further reduced while improving the properties.

<< Aspect 10 >>
The absorbent article according to aspect 9, wherein the bonding area between the diffusion sheet and the intermediate sheet is more than 0.5% and 20.0% or less of the area of the diffusion sheet.

When the diffusion sheet is bonded to the intermediate sheet by, for example, adhesion by adhesive, adhesion by heat fusion, etc., such a bonded portion has low diffusibility of excrement liquid. In the absorbent article according to the tenth aspect of the present disclosure, since the bonding area between the diffusion sheet and the intermediate sheet is within a certain range, the diffusion property can be improved while maintaining the bonding.

<< Aspect 11 >>
It has an absorbent core and an absorber having a core wrap sheet covering at least the skin non-opposing surface side of the absorbent core, and the diffusion sheet is the absorbent core and the core wrap sheet. Arranged between,
The absorbent article according to any one of aspects 1 to 6.

In the absorbent article according to the eleventh aspect of the present disclosure, since the diffusion sheet directly receives and diffuses the excrement liquid flowing out from the absorption core, the excrement liquid is diffused in the in-plane direction of the absorbent article in a shorter time. Can be done. Further, in the absorbent article according to the eleventh aspect of the present disclosure, since the diffusion sheet is in contact with the absorption core, the superabsorbent polymer in the absorption core easily absorbs and retains the excrement liquid diffused by the diffusion sheet. .. Further, in the absorbent article according to the eleventh aspect of the present disclosure, the core wrap sheet is interposed between the diffusion sheet and the moisture permeable back sheet to improve the transpiration property of the moisture permeable back sheet and to improve the transpiration property of the moisture permeable back sheet. The amount of wetness can be reduced.

<< Aspect 12 >>
The absorbent article according to any one of aspects 8 to 11, wherein the thickness of the absorber is 1.5 mm or more and 3.0 mm or less.

In the absorbent article according to the 12th aspect of the present disclosure, since the absorber has a thickness within a certain range, the heat dissipation of the absorber itself is improved while ensuring the absorbability of the excrement liquid by the absorber. By doing so, the temperature drop due to transpiration can be further improved.

<< Aspect 13 >>
A non-woven fabric back sheet having a breathability in the thickness direction of 100 cm ³ / cm ² · min or more and 4000 cm ³ / cm ² · min or less is further laminated on the non-skin facing surface side of the moisture permeable back sheet. The absorbent article according to any one of 1 to 12.

In the absorbent article according to the thirteenth aspect of the present disclosure, the non-skin facing surface of the moisture permeable back sheet is further covered with a non-woven fabric back sheet, so that the amount of wetness of the portion of the absorbent article in contact with clothing is reduced. At the same time, the appearance can be improved.

<< Aspect 14 >>
The absorption core has an excrement diffusion region extending in at least one direction in the plane, the basis weight of the superabsorbent polymer is lower than that of other parts of the absorption core, embodiments 1 to 13. The absorbent article according to any one of.

In the absorbable article according to the 14th aspect of the present disclosure, since the absorption core has an excretion liquid diffusion region, the excretion liquid is diffused in the in-plane direction of the absorption core at the time of excretion, so that the excretion liquid is discharged. It can flow into the diffusion sheet over a larger area. Therefore, in the absorbent article according to aspect 14 of the present disclosure, the diffusibility of the excrement liquid by the diffusion sheet can be further improved.

According to the present disclosure, it is possible to provide an absorbent article capable of suppressing dew condensation on the outside of the absorbent article while lowering the temperature and absolute humidity inside the absorbent article.

FIG. 1 is a schematic view of a tape-type diaper 1 according to the first embodiment of the present disclosure in an unfolded state as viewed from the skin-facing surface side. FIG. 2 is a cross-sectional view of the tape-type diaper 1 according to the first embodiment of the present disclosure along the II-II cross section of FIG. FIG. 3 is a schematic view showing a state in which the excrement liquid is transpired from the moisture-permeable back sheet 13 in the tape-type diaper 1 according to the first embodiment of the present disclosure. FIG. 4 is a cross-sectional view of the tape-type diaper 1 according to the second embodiment of the present disclosure along a cross section similar to the II-II cross section of FIG. FIG. 5 is a cross-sectional view of the tape-type diaper 1 different from the embodiment of the present disclosure along a cross section similar to that of the II-II cross section of FIG. FIG. 6 is a schematic view showing a state in which the excrement liquid is transpired from the moisture-permeable back sheet 13 in the tape-type diaper 1 different from the embodiment of the present disclosure. FIG. 7 is a schematic view of the tape-type diaper 1 according to the third embodiment of the present disclosure in the unfolded state as viewed from the skin-facing surface side. FIG. 8 is a cross-sectional view of the tape-type diaper 1 according to the third embodiment of the present disclosure along the section III-III of FIG. FIG. 9 is a cross-sectional view of the tape-type diaper 1 according to the fourth embodiment of the present disclosure along a cross section similar to that of the II-II cross section of FIG. FIG. 10 is a cross-sectional view of the tape-type diaper 1 according to the fifth embodiment of the present disclosure along a cross section similar to the II-II cross section of FIG. FIG. 11 is a schematic view showing an apparatus for measuring the amount of transpiration of the samples of Examples 1 to 4 and Comparative Examples 1 and 2 and the amount of wetness of the permeable backsheet. FIG. 12 is a schematic view showing an apparatus for measuring the temperature and absolute humidity of the samples of Examples 1 to 4 and Comparative Examples 1 and 2.

Hereinafter, embodiments of the present disclosure will be described in detail. It should be noted that the present disclosure is not limited to the following embodiments, but can be variously modified within the scope of the main purpose of the disclosure.

The "longitudinal direction" of the absorbent article indicates the long direction of the length of the absorbent article in the unfolded state of the absorbent article. The "width direction" indicates a direction that is perpendicular to the thickness direction of the absorbent article and orthogonal to the "longitudinal direction" in the unfolded state of the absorbent article. It should be noted that one end in the "longitudinal direction" is located on the front side of the wearer's body when the absorbent article is worn, and the other end in the longitudinal direction is located on the rear side of the wearer's body. To do. The "longitudinal direction" and the "width direction" used for the constituent members of the absorbent article mean the same directions as the "longitudinal direction" and the "width direction" of the absorbent article, respectively.

The "skin-facing surface" of the absorbent article is the surface of the absorbent article that faces the skin when worn in the deployed state of the absorbent article. Further, the "non-skin facing surface" of the absorbent article is a surface of the absorbent article that does not face the skin when worn in the deployed state of the absorbent article. The "skin facing surface" and "skin non-facing surface" used for the constituent members of the absorbent article mean surfaces in the same direction as the "skin facing surface" and "skin non-facing surface" of the absorbent article, respectively. There is.

The absorbent article of the present disclosure is an absorbent article in which an absorbent core, a diffusion sheet, and a moisture-permeable back sheet are laminated in this order from the skin facing surface side to the skin non-facing surface side, and the absorbent core is , mainly of the superabsorbent polymer, the diffusion sheet, mainly of hydrophilic fibers and has a Klemm water absorbency 100mm or more, and moisture-permeable backsheet in moisture permeability 1500g / m 2 / ^24h or more is there.

Note that the forms of the absorbent articles disclosed in the present disclosure include, but are not limited to, tape-type diapers and pants-type diapers.

Although not limited by the principle, in the absorbent article of the present disclosure, the principle capable of suppressing dew condensation on the outside of the absorbent article while lowering the temperature and absolute humidity inside the absorbent article is as follows. It is as follows.

The absorbent article of the present disclosure uses an absorbent core mainly made of a super absorbent polymer to reduce the temporary water retention of excrement by the absorbent core, that is, the water retention that can be discharged. Then, the excrement liquid that has flowed to the non-skin facing surface side of the absorption core without being retained by the super absorbent polymer in the absorption core is diffused in the in-plane direction of the absorbent article by the diffusion sheet. As a result, the area in which the excrement liquid comes into contact with the moisture-permeable back sheet is increased, the water in the excrement liquid is efficiently evaporated from the moisture-permeable back sheet, and the amount of evaporation per unit area of the moisture-permeable back sheet is reduced. .. In addition, since the area of the superabsorbent polymer in contact with the excrement liquid also increases, the water retention of the excrement liquid by the superabsorbent polymer also improves.

Therefore, the absorbent article of the present disclosure can reduce dew condensation on the non-skin facing surface side of the moisture permeable backsheet while lowering the temperature and absolute humidity inside the absorbent article.

A tape-type diaper according to the embodiment of the present disclosure and a tape-type diaper different from the embodiment of the present disclosure will be used for more specific explanation.

1 and 2 are schematic views of a tape-type diaper 1 according to the first embodiment of the present disclosure. FIG. 1 is a schematic view of a tape-type diaper 1 according to the first embodiment of the present disclosure in an unfolded state as viewed from the skin-facing surface side. Further, FIG. 2 is a cross-sectional view of the tape-type diaper 1 according to the first embodiment of the present disclosure, along the II-II cross section of FIG.

As shown in FIGS. 1 and 2, the tape-type diaper 1 according to the first embodiment of the present disclosure has an absorbent main body 10a and a pair of locking members 3. Further, the absorbent main body 10a has a top sheet 11, an absorbent body 12, a moisture permeable back sheet 13, and a non-woven fabric back sheet 14 in this order in the thickness direction T. Then, the absorber 12 has the upper layer core wrap sheet 12b, the absorption core 12a, and the lower layer core wrap sheet 12c in this order in the thickness direction T.

In the absorbent body 10a, the lower core wrap sheet 12c is a diffusion sheet. Further, in the absorbent main body 10a, the lower core wrap sheet 12c covers the end portion of the upper core wrap sheet 12b in the width direction W.

Although not shown, the absorption core 12a is mainly made of a super absorbent polymer, and the diffusion sheet as the lower core wrap sheet 12c is mainly made of hydrophilic fibers and has a Krem water absorption of 100 mm or more. The moisture-permeable back sheet 13 has a moisture permeability of 1500 g / m ² / 24h or more.

FIG. 3 is a schematic view showing a state in which the excrement liquid is transpired from the moisture-permeable back sheet 13 in the tape-type diaper 1 according to the first embodiment of the present disclosure.

As shown in FIG. 3, when the wearer excretes, the excrement liquid passes through the top sheet 11 of the absorbent main body 10a and mainly passes through the upper core wrap sheet 12b from the portion adjacent to the wearer's excretion port. And flows into the absorption core 12a. Here, since the absorption core 12a is mainly composed of a superabsorbent polymer having a slow rate of absorbing and retaining water, most of the excrement passes through the superabsorbent polymer and the lower core wrap sheet. Reach 12c.

Here, since the lower core wrap sheet 12c is composed of a diffusion sheet, the excrement liquid that has reached the lower core wrap sheet 12c is in the in-plane direction of the absorber 12, that is, for example, the width direction W of the absorber 12 and / Or diffuse in the longitudinal direction L.

As a result, the area in which the excrement liquid comes into contact with the moisture permeable back sheet 13 increases, the water in the excrement liquid evaporates efficiently from the moisture permeable back sheet 13, and the amount of evaporation per unit area of the moisture permeable back sheet 13 increases. It will be reduced. In addition, since the area of the superabsorbent polymer in contact with the excrement liquid in the absorption core 12a also increases, the water retention of the excrement liquid by the superabsorbent polymer is also improved.

Further, in the absorbent main body 10a, the lower core wrap sheet 12c covers at least a part of the end portion of the upper layer core wrap sheet 12b in the width direction W, so that the lower layer core wrap sheet 12c covers at least a part of the end portion of the absorbent main body 10a in the width direction W. The flowed excrement tends to diffuse in the in-plane direction of the lower core wrap sheet 12c through the portion of the lower core wrap sheet 12c.

As a result, it is possible to prevent the excrement liquid from being unevenly accumulated at the end of the absorbent body 10a in the width direction W, and to suppress the lateral leakage of the excretion liquid.

FIG. 4 is a cross-sectional view of the tape-type diaper 1 according to the second embodiment of the present disclosure along a cross section similar to the II-II cross section of FIG.
As shown in FIG. 4, the absorbent body 12 included in the absorbent body 10b included in the tape-type diaper 1 according to the second embodiment of the present disclosure is the upper core wrap sheet 12b in the thickness direction T. , The absorption core 12a, the intermediate layer core wrap sheet 12d, the absorption core 12a, and the lower layer core wrap sheet 12c in this order.

Further, in the absorbent main body 10b, the lower core wrap sheet 12c covers the ends of the upper core wrap sheet 12b and the intermediate layer core wrap sheet 12d in the width direction W, and further, the intermediate layer core wrap sheet 12d and the lower layer. The entire end of the absorption core 12a arranged between the core wrap sheets 12c in the width direction W, and the width direction W of the absorption core 12a arranged between the upper core wrap sheet 12b and the intermediate layer core wrap sheet 12d. It covers a part of the end of the.

Even in such an embodiment in which a plurality of absorbing cores are partitioned by an intermediate layer core wrap sheet, a moisture permeable back sheet is used to reduce the temperature and absolute humidity inside the absorbent article by the same principle as in FIG. Condensation on the non-skin facing surface side can be reduced.

FIG. 5 is a cross-sectional view of the tape-type diaper 1 different from the embodiment of the present disclosure along a cross section similar to the II-II cross section of FIG.

In FIG. 5, the absorbent body 10'has the same structure as in FIG. 2 except that the lower core wrap sheet 12c' is not a diffusion sheet.

FIG. 6 is a schematic view showing a state in which the excrement liquid is transpired from the moisture-permeable back sheet 13 in the tape-type diaper 1 different from the embodiment of the present disclosure.

As shown in FIG. 6, when the wearer excretes, the excrement liquid passes through the top sheet 11 of the absorbent body 10a and concentrates on the absorber 12 mainly from the portion adjacent to the wearer's excretion port. It flows in and flows into the absorption core 12a. Here, since the absorption core 12a is mainly composed of a superabsorbent polymer having a slow rate of absorbing and retaining water, most of the excrement passes through the superabsorbent polymer and the lower core wrap sheet 12c 'Reach.

Since the lower core wrap sheet 12c'is not composed of the diffusion sheet, the excrement liquid that reaches the lower core wrap sheet 12c'is in the in-plane direction of the absorber 12, that is, for example, the width direction W of the absorber 12. And / or cannot diffuse sufficiently in the longitudinal direction L.

Therefore, the amount of evaporation is small because the water in the excrement evaporates from a part of the moisture-permeable back sheet 13. Further, since the water in the excrement liquid evaporates intensively from a part of the moisture permeable backsheet 13, dew condensation 30 is likely to occur in that part.

《Absorption core》
The absorption core is a member that retains water in the excrement liquid. The absorption core is mainly composed of a super absorbent polymer.

The superabsorbent polymer is not particularly limited as long as it is a polymer capable of absorbing water and sustainably retaining water, and examples thereof include particulate or fibrous superabsorbent polymers.

Examples of the super absorbent polymer include starch-based, cellulosic-based, and synthetic polymer-based polymer absorbers. Examples of the starch-based or cellulosic-based highly water-absorbent polymer include a starch-acrylic acid (salt) graft copolymer, a saponified product of a starch-acrylonitrile copolymer, and a crosslinked product of sodium carboxymethyl cellulose. Examples of the synthetic polymer-based superabsorbent polymer include polyacrylate-based, polysulfone-based, maleic anhydride-based, polyacrylamide-based, polyvinyl alcohol-based, polyethylene oxide-based, polyasparaginate-based, and polyglutamic acid. Examples thereof include salt-based, polyarginate-based, starch-based, and cellulose-based.

When the superabsorbent polymer is in the form of particles, it is preferable that 90 to 100% by mass of the superabsorbent polymer is composed of superabsorbent polymer particles having a particle size of 150 to 500 μm. Since the superabsorbent polymer particles having such a particle size distribution have a small particle size and are uniform, they are easily held by the adhesive.

The particle size of the superabsorbent polymer particles is measured in accordance with the "sieving test method" described in JIS R 6002: 1998.

The fact that the absorption core is "mainly" composed of a superabsorbent polymer means that the content of the superabsorbent polymer in the absorption core is 80% by mass or more with respect to the entire absorption core.

The content of the superabsorbent polymer in the absorption core may be 80% by mass or more, 90% by mass or more, or 95% by mass or more, and 100% by mass or less, 99% by mass or less, 95% by mass or less, or 90% by mass. It may be less than or equal to%.

The absorption core preferably does not contain hydrophilic fibers, for example, water-absorbent fibers such as pulp fibers.

It is preferable that the absorption core has an excrement diffusion region extending in at least one direction in the plane and having a basis weight of the superabsorbent polymer lower than the basis weight of other parts of the absorption core.

When the absorption core has an excretion liquid diffusion region, the excretion liquid can be made to flow into the diffusion sheet over a wider area by diffusing the excretion liquid in the in-plane direction of the absorption core at the time of excretion. Thereby, the diffusibility of the excrement liquid by the diffusion sheet can be further improved.

If the basis weight of the superabsorbent polymer in the excrement diffusion region is lower than the basis weight of other parts of the absorption core, the basis weight is not particularly limited, but for example, the basis weight of the superabsorbent polymer in the excrement diffusion region. May be 0.75 times or less the basis weight of other parts of the absorption core, and the excrement diffusion region may not contain a super absorbent polymer.

The basis weight of the superabsorbent polymer in the excrement diffusion region is 0.75 times or less, 0.50 times or less, 0.25 times or less, or 0.10 times or less the basis weight of the other part of the absorption core. It may be 0.05 times or more, 0.10 times or more, 0.20 times or more, or 0.50 times or more.

The excretory liquid diffusion region may be arranged on the skin facing surface side and / or the skin non-facing surface side of the absorption core.

7 and 8 are schematic views of the tape-type diaper 1 according to the third embodiment of the present disclosure. FIG. 7 is a schematic view of the tape-type diaper 1 according to the third embodiment of the present disclosure in the unfolded state as viewed from the skin-facing surface side. Further, FIG. 8 is a cross-sectional view of the tape-type diaper 1 according to the third embodiment of the present disclosure, along the cross-section III-III of FIG.

7 and 8, respectively, in the absorbent body 10c, the absorbent core 12a has an excrement diffusion region 40 in which the basis weight of the superabsorbent polymer is lower than that of other parts of the absorbent core 12a over the longitudinal direction L. It has the same structure as that of FIGS. 1 and 2 except that the structure is the same.

As shown in FIG. 8, in the absorbent body 10b, the absorbent core 12a arranged between the upper core wrap sheet 12b and the lower core wrap sheet 12c has an excrement diffusion region 40.

As a result, at the time of excretion, the excrement liquid is diffused in the longitudinal direction L of the absorption core, so that the excretion liquid can flow into the diffusion sheet over a wider area.

《Diffusion sheet》
The diffusion sheet is a sheet capable of diffusing the excrement liquid in the in-plane direction of the sheet. The direction in which the diffusion sheet diffuses the excrement may be at least one direction in the in-plane direction of the diffusion sheet. Therefore, the direction in which the diffusion sheet diffuses the excrement may be the longitudinal direction, the width direction, and / or the direction in which the diffusion sheet is inclined in these directions in the plane.

The diffusion sheet is mainly composed of hydrophilic fibers and has a Krem water absorption of 100 mm or more.

Here, the hydrophilic fiber means that the fiber itself has hydrophilicity from the beginning, and the hydrophobic fiber is hydrophilically processed, for example, the surface of the hydrophobic fiber is coated with a hydrophilic binder. Fibers, etc. are not included.

This is to prevent the surface tension of the excretory liquid from being lowered due to the hydrophilic binder or the like covering the surface of the hydrophobic fiber being eluted into the excrement liquid.

Examples of hydrophilic fibers include, but are not limited to, pulp fibers and rayon fibers.

The fact that the diffusion sheet is "mainly" composed of hydrophilic fibers means that the content of the hydrophilic fibers in the diffusion sheet is more than 50% by mass with respect to the entire diffusion sheet.

The content of the hydrophilic fiber in the diffusion sheet may be more than 50% by mass, 60% by mass or more, 70% by mass or more, 80% by mass or more, 90% by mass or more, or 95% by mass or more, and 100% by mass or less. , 99% by mass or less, 95% by mass or less, 90% by mass or less, or 80% by mass or less.

The hydrophilic fiber may have a basis weight of 10 g / m ² or more and 100 g / m ² or less. The basis weight of the hydrophilic fiber may be 10 g / m ² or more, 25 g / m ² or more, 35 g / m ² or more, or 45 g / m ² or more, 100 g / m ² or less, 90 g / m ² or less, 80 g. / ^{m 2} or less, or 70 g / ^m may be ² or less.

The hydrophilic fiber preferably has a basis weight of 35 g / m ² or more and a Krem water absorption of 130 mm or more.

The Krem water absorption may be 100 mm or more, 130 mm or more, 150 mm or more, 170 mm or more, or 200 mm or more, and may be 300 mm or less, 250 mm or less, 200 mm or less, 170 mm or less, or 150 mm or less.

Krem water absorption is measured in accordance with JIS P 8141: 2004.

When the basis weight of the hydrophilic fibers contained in the diffusion sheet and the water absorption of Krem are within such a range, the diffusibility of the excrement liquid by the diffusion sheet can be improved.

Therefore, the water retention of the superabsorbent polymer in the absorption core can be further improved, and the amount of water vaporized from the moisture-permeable backsheet in the excrement liquid can be further increased.

The hydrophilic fiber preferably contains rayon fiber having streaks on the surface along the direction in which the fiber extends.

Here, the "direction in which the fiber extends" is the direction from one end to the other end in the axial direction of the fiber.

As a rayon fiber having streaks along the extending direction of the fiber on the surface, for example, the rayon fiber has one or more streaks in the axial direction of the fiber and has a cross-sectional shape in the direction orthogonal to the axial direction of the fiber. , Rayon fibers having regular or irregular irregularities can be mentioned.

Rayon fibers having streaks on the surface along the direction in which the fibers extend are likely to diffuse excrement along the direction in which the fibers extend due to the capillary force formed by the grooves formed by the streaks. Therefore, when the hydrophilic fibers in the diffusion sheet are rayon fibers having streaks along the extending direction of the fibers on the surface, the diffusivity of the excrement liquid by the diffusion sheet is high, and the water retention by the super absorbent polymer in the absorption core is increased. It can be further improved, and the amount of water vaporized from the moisture-permeable backsheet in the excrement liquid can be further increased.

The diffusion sheet preferably covers at least a part of at least one end in the longitudinal direction and the width direction of the absorption core.

The diffusion sheet may cover the entire outer circumference of the absorption core, or may cover at least one end in the longitudinal direction of the absorption core and / or at least one end in the width direction of the absorption core. Further, the diffusion sheet may cover all or a part of the absorption core in the thickness direction.

The diffusion sheet may cover the absorption core so as to be in contact with the absorption core, or may indirectly cover the absorption core with another sheet or the like between the diffusion sheet and the absorption core.

When the diffusion sheet covers at least a portion of at least one end in the longitudinal and width directions of the absorbent layer, it absorbs the excrement that has flowed to the anterior, posterior, and / or lateral sides of the absorbent article. Since it is easy to diffuse in the in-plane direction of the sex article, it is possible to suppress the bias of the excrement liquid inside the absorbent article and suppress the front leakage, the rear leakage, and / or the lateral leakage of the excretion liquid.

《Breathable back sheet》
The moisture-permeable back sheet is a sheet that evaporates the water in the excrement liquid as water vapor to the outside of the absorbent article while suppressing the excrement liquid from leaking to the outside of the absorbent article.

The moisture-permeable back sheet is not particularly limited as long as it is a sheet that does not easily permeate water and easily permeates water vapor. Examples of the moisture-permeable back sheet include, but are not limited to, synthetic paper made of a polyolefin material and a polyolefin film having micropores.

The moisture permeability of the moisture permeable back sheet is 1500 g / m ² / 24h or more. This is because if the moisture permeability of the moisture-permeable back sheet is too low, the water in the excrement liquid cannot be sufficiently evaporated.

Moisture permeability of moisture vapor permeable backsheet, 1500g ^/ m 2 ^/ 24h or more, it may be less 4500g ^/ m 2 ^/ 24h.

Moisture permeability of moisture vapor permeable backsheet, 1500g ^/ m 2 ^/ 24h or more, 2000g ^/ m 2 ^/ 24h or more, 2500g ^/ m 2 ^/ 24h or more, or may be at 3000g ^/ m 2 ^/ 24h or more, 4500 g / ^{m 2} / 24h or less, 3500 g ^/ m 2 / 24h or less, 3000 g ^/ m 2 / 24h or less, or 2500 g ^/ m 2 / 24h may be less.

The moisture permeability of the moisture permeable back sheet is preferably 3500 g / m ² / 24h or less.

When the moisture permeability of the moisture-permeable backsheet is below a certain level, dew condensation on the non-skin facing surface side of the moisture-permeable backsheet is further suppressed, so that the absolute humidity between the wearer's clothing, such as underwear, and the skin The absolute humidity between the wearer's clothes, such as underwear, and the skin can be maintained within an appropriate range even after excretion, for example, after urination, and the comfort can be further improved.

Moisture permeability is measured according to JIS Z 0208 1976 "Humidity Permeability Test Method for Moisture-Proof Packaging Materials (Cup Method)".

It is preferable that the diffusion sheet does not substantially contain a surfactant.

Here, the term "substantially" that the diffusion sheet does not contain a surfactant means that the diffusion sheet does not contain a surfactant, or the diffusion sheet uses the surfactant as an impurity to diffuse the excrement. It means that it is contained to the extent that it does not affect the surface tension of the excrement liquid when it comes into contact with the sheet.

When the diffusion sheet does not substantially contain a surfactant, it is possible to suppress a decrease in the surface tension of the excrement liquid due to the mixture of the surfactant in the excrement liquid, and the moisture-permeable back sheet can be used. Liquid leakage can be further suppressed. Further, among the members constituting the absorbent article, it is preferable that the other members in contact with the excrement liquid do not substantially contain the surfactant.

"Absorber"
The absorbent article can have an absorbent core as an absorber having an absorbent core. The absorber can have a core wrap sheet that covers the absorbent core and at least the non-skin facing side of the absorbent core.

The absorber can have an upper layer core wrap sheet, an absorption core, and a lower layer core wrap sheet in this order from the skin facing surface side to the skin non-facing surface side of the absorber. Further, the absorber can have a plurality of absorption cores, in which case the plurality of absorption cores can be partitioned by an intermediate layer core wrap sheet.

Further, the upper layer core wrap sheet, the intermediate layer core wrap sheet, the lower layer core wrap sheet, and the absorption core may be adhered to each other by an adhesive.

The thickness of the absorber is preferably 1.5 mm or more and 3.0 mm or less.

Since the absorber has a thickness within a certain range, the heat dissipation of the absorber itself is improved while ensuring the absorbability of the excrement liquid by the absorber, thereby further improving the temperature drop due to transpiration. Can be done.

The thickness of the absorber may be 1.5 mm or more, 2.0 mm or more, 2.3 mm or more, 2.5 mm or more, or 2.8 mm or more, and 3.0 mm or less, 2.8 mm or less, 2.5 mm or less. , Or may be 2.3 mm or less.

The thickness of the absorber is calculated as the average value of the three measured values by measuring three points of the absorber using a thickness gauge (made by PEACOCK, 50 mmφ, 3 g / cm ² , with a spring).

The core wrap sheet may be the above-mentioned diffusion sheet, but may not be the above-mentioned diffusion sheet.

(When the core wrap sheet is a diffusion sheet)
When the core wrap sheet is the above-mentioned diffusion sheet, the diffusion sheet constitutes the core wrap sheet, so that a separate member for diffusing the excrement is not required, and the thickness of the absorbent article is reduced. be able to. Further, since the diffusion sheet directly receives and diffuses the excrement liquid flowing out from the absorption core, the excretion liquid can be diffused in the in-plane direction of the absorbent article in a shorter time. In addition, since the diffusion sheet is in contact with the absorption core, the absorption core easily absorbs the excrement liquid diffused by the diffusion sheet.

When the diffusion sheet as the core wrap sheet and the moisture permeable back sheet are bonded, the bonding area between the diffusion sheet and the moisture permeable back sheet is more than 0.5% and 20.0% of the area of the diffusion sheet. The following is preferable.

When the diffusion sheet, which is a core wrap sheet, is bonded to the moisture-permeable back sheet by, for example, bonding with an adhesive, bonding by heat fusion, etc., such a bonded portion has low diffusibility of excrement liquid. When the bonding area between the diffusion sheet, which is a core wrap sheet, and the moisture-permeable back sheet is within a certain range, the diffusion property can be improved while maintaining the bonding.

The bonding area between the diffusion sheet and the moisture permeable back sheet may be more than 0.5%, 1.0% or more, 5.0% or more, 10.0% or more, or 15.0% or more, and 20. It may be 0% or less, 18.0% or less, 15.0% or less, 10.0% or less, or 5.0% or less.

The bonding area between the diffusion sheet and the moisture-permeable back sheet means the area of the surface of the diffusion sheet where the diffusion sheet and the moisture-permeable back sheet are bonded in the unfolded state of the absorbent article. This area is determined by applying the adhesive on the diffusion sheet, for example, when the diffusion sheet and the breathable back sheet are bonded by an adhesive in a pattern such as spiral, stripe, dot (scattered point), wave (wavy). The area of the part is defined as the joint area. However, of the adhesives coated with multiple lines of stripes, dots (scattered dots), waves (wavy lines), etc., the parts where the distance between them is within 5 mm are also joined between the patterns. I reckon. Further, in the case of a coating having a non-adhesive coating portion surrounded by an adhesive coating portion such as a spiral pattern, it is considered that the non-adhesive coating portion is also joined.
When measuring the joint area from a commercially available absorbent article, it can be measured by the following method. First, the diffusion sheet and the moisture-permeable back sheet are taken out from a commercially available absorbent article, put into a developed state, and toner is applied. Next, the toner is removed by blowing air. Then, the adhesive-coated portion colored by the toner is observed. After that, it is binarized using image processing software to obtain the joint area.

When the diffusion sheet constitutes the core wrap sheet, the hydrophilicity between the diffusion sheet and the moisture-permeable back sheet is lower than that of the diffusion sheet, and the dynamic wetting index is more than 0.0 seconds, 0.2. It is preferable that intermediate sheets that are less than a second are laminated.

By interposing an intermediate sheet that has hydrophilicity but does not easily retain excrement between the diffusion sheet and the moisture-permeable backsheet, the transpiration property of the moisture-permeable backsheet is improved and the amount of moisture in the moisture-permeable backsheet is increased. It can be further reduced.

For the dynamic wetting index, the sample, distilled water, and contact angle meter (CA-S Micro Type 2 manufactured by Kyowa Interface Science Co., Ltd.) were left in a constant temperature and humidity chamber for 24 hours or more to stabilize the temperature. After that, the sample is measured three times with a contact angle meter, and it is obtained as the average value of the measured values.

When the diffusion sheet and the intermediate sheet are bonded, the bonding area between the diffusion sheet and the intermediate sheet is preferably more than 0.5% and 20.0% or less of the area of the diffusion sheet.

When the diffusion sheet is bonded to the intermediate sheet by, for example, adhesion by adhesive, adhesion by heat fusion, etc., such a bonded portion has low diffusibility of excrement liquid.

When the bonding area between the diffusion sheet and the intermediate sheet is within a certain range, it is possible to improve the diffusivity while maintaining the bonding.

The joint area between the diffusion sheet and the intermediate sheet may be more than 0.5%, 1.0% or more, 5.0% or more, 10.0% or more, or 15.0% or more, and 20.0%. Hereinafter, it may be 18.0% or less, 15.0% or less, 10.0% or less, or 5.0% or less.

The joint area between the diffusion sheet and the intermediate sheet can be obtained by referring to the above method for calculating the joint area between the diffusion sheet and the moisture permeable back sheet.

FIG. 9 is a cross-sectional view of a tape-type diaper according to a fourth embodiment of the present disclosure along a cross section similar to the II-II cross section of FIG.

As shown in FIG. 9, the absorbent main body 10d of this tape-type diaper has an intermediate sheet 15 between the lower core wrap sheet 12c as a diffusible sheet and the moisture-permeable back sheet 13. Although not shown, the intermediate sheet 15 is less hydrophilic than the diffusion sheet and has a dynamic wetting index of 0 to 0.2 seconds. The remaining configuration is the same as in FIG.

In the tape-type diaper according to the fourth embodiment of the present disclosure, the intermediate sheet 15 is arranged between the lower core wrap sheet 12c as a diffusion sheet and the breathable back sheet 13, so that the lower core wrap sheet 12c and the lower layer core wrap sheet 12c are arranged. Since the moisture-permeable back sheet 13 does not come into direct contact with the moisture-permeable back sheet 13, the amount of excrement liquid that comes into contact with the moisture-permeable back sheet 13 is reduced, and the evaporation of the excretory liquid in the moisture-permeable back sheet 13 is improved. The amount of wetness of the sheet 13 can be reduced.

(If the core wrap sheet is not a diffusion sheet)
If the core wrap sheet is not the above diffusion sheet, the diffusion sheet can be placed between the absorbent core and the core wrap sheet.

When the absorbent article has such a structure, the diffusion sheet directly receives and diffuses the excrement liquid flowing out from the absorption core, so that the excrement solution can be diffused in the in-plane direction of the absorbent article in a shorter time. it can. Further, since the diffusion sheet is in contact with the absorption core, the absorption core easily absorbs the excrement liquid diffused by the diffusion sheet. Further, by interposing a core wrap sheet between the diffusion sheet and the moisture permeable back sheet, it is possible to reduce the amount of wetness of the moisture permeable back sheet while improving the transpiration property of the moisture permeable back sheet.

FIG. 10 is a cross-sectional view of the tape-type diaper 1 according to the fifth embodiment of the present disclosure along a cross section similar to the II-II cross section of FIG.

As shown in FIG. 10, the absorbent body 10e of the tape-type diaper 1 has a diffusion sheet 16 between the absorbent core 12a and the lower core wrap sheet 12c.

In the tape-type diaper 1 according to the fifth embodiment of the present disclosure, since the diffusion sheet 16 is in direct contact with the absorption core 12a, the excrement liquid flowing out from the absorption core 12a can be directly received and diffused. As a result, the excrement liquid can be diffused in the in-plane direction of the absorbent article in a shorter time. Further, since the diffusion sheet 16 is in direct contact with the absorption core 12a, the absorption core 12a easily absorbs the excrement liquid diffused by the diffusion sheet 16. Further, since the lower core wrap sheet 12c is interposed between the diffusion sheet 16 and the moisture permeable back sheet 13, the amount of wetness of the moisture permeable back sheet 13 is reduced while improving the transpiration of the moisture permeable back sheet 13. can do.

《Non-woven back sheet》
The absorbent article of the present disclosure includes a non-woven fabric back sheet having a breathability in the thickness direction of 100 cm ³ / cm ² · min or more and 4000 cm ³ / cm ² · min or less on the non-skin facing side of the breathable back sheet. Further laminated is preferable.

By further covering the non-skin facing surface of the moisture-permeable backsheet with such a non-woven fabric backsheet, it is possible to reduce the amount of moisture in the portion of the absorbent article that comes into contact with clothing and improve the appearance. ..

Examples of the non-woven fabric back sheet include, but are not limited to, spunbonded non-woven fabric and SMS non-woven fabric.

The air permeability of the non-woven back sheet in the thickness direction is 100 cm ³ / cm ² min or more, 500 cm ³ / cm ² min or more, 1000 cm ³ / cm ² min or more, 1500 cm ³ / cm ² min or more, or 2000 cm. ³ / cm may be ² · min or more, 4000 cm ³ / cm ² · min or less, 3500 cm ³ / cm ² · min or less, 3000 cm ³ / cm ² · min or less, 2500 cm ³ / cm ² · min or less, 2000 cm ³ It may be less than / cm ² · min, or less than 1500 cm ³ / cm ² · min.

The air permeability of the non-woven fabric back sheet in the thickness direction is measured by the following method using a KES-F8-AP1 air permeability tester manufactured by Kato Tech Co., Ltd.

First, the KES-F8-AP1 air permeability tester and sample are allowed to stand in a constant temperature and humidity chamber (temperature: 25 ± 5 ° C., relative humidity: 65 ± 5%) for 24 hours. Then, the ventilation resistance value of the sample is measured at a piston speed of 2 cm / sec. This measurement is repeated 5 times with different samples, and the average value of the measured values is taken as the ventilation resistance value R (kPa · s / m) of the sample.

This ventilation resistance value R is converted into a ventilation AP (cm ³ / cm ² / min) according to the following formula (1).

AP = 12.5R (1)

The absorbent articles to which the present disclosure applies are not limited to the tape-type diapers of each of the above embodiments, and can be applied to absorbent articles in general, for example, sanitary napkins, light incontinence pads, and panties. It can be applied to various absorbent articles such as sanitary products such as liners and pants-type diapers. Further, each member constituting the absorbent article also includes various members depending on the type of the absorbent article to be applied, in addition to the above-mentioned members, etc., as long as the effect of the present disclosure is exhibited. Can be done.

<< Examples 1 to 4 and Comparative Examples 1 to 3 >>
<Example 1>
The upper layer core wrap sheet, the absorption core, the intermediate layer core wrap sheet, the absorption core, and the lower layer core wrap sheet are joined in this order with a hot melt adhesive (basis weight 5 g / m ² ) and pressed. As a result, the absorber was molded. The absorber was a rectangle having a width of 120 mm and a length of 250 mm. Here, the upper layer core wrap sheet is a hydrophilic SMS non-woven fabric (basis weight 10 g / m ² ), the intermediate layer core wrap sheet is an air-through non-woven fabric (basis weight 40 g / m ² ), and the lower layer core wrap sheet is a pulp-containing span as a diffusion sheet. The race (basis weight 55 g / m ² , pulp water absorption 170 mm), the absorption core was a super absorbent polymer (Sumitomo Seika Co., Ltd. Aquakeep SA60S).

Next, it was joined to the upper surface side of the absorber, that is, the surface side corresponding to the skin facing surface, via an air-through non-woven fabric (basis weight 30 g / m ² ) as a top sheet and a hot melt adhesive (basis weight 5 g / m ² ). .. Then, a moisture-permeable film as a moisture-permeable back sheet (basis weight 30 g / m ² , moisture permeability 3130 g / m ² / 24h, width 150 mm, length 380 mm) is applied, and a hot melt adhesive (basis weight 5 g / m ² ) is applied. The evaluation sample of Example 1 was completed by joining to the lower surface side of the absorber, that is, the surface side corresponding to the non-skin facing surface.

<Example 2>
The evaluation sample of Example 2 was prepared in the same manner as in Example 1 except that rayon spunlace (basis weight 43 g / m ² , Krem water absorption 170 mm) was used as the diffusion sheet as the lower core wrap sheet. Made.

<Example 3>
The evaluation sample of Example 3 was prepared in the same manner as in Example 1 except that rayon spunlace (basis weight 30 g / m ² , Krem water absorption 130 mm) was used as the diffusion sheet as the lower core wrap sheet. Made.

<Comparative example 1>
An evaluation sample of Comparative Example 1 was prepared in the same manner as in Example 1 except that an air-laid non-woven fabric (basis weight 50 g / m ² , Krem water absorption 48 mm) was used as the lower core wrap sheet.

<Comparative example 2>
An evaluation sample of Comparative Example 2 was prepared in the same manner as in Example 1 except that a hydrophilic SMS non-woven fabric (basis weight 10 g / m ² ) was used as the lower core wrap sheet.

<Comparative example 3>
As an absorption core, a mixture of a super absorbent polymer (basis weight 250 g / m ² , Sumitomo Seika Co., Ltd. Aquakeep SA60S) and pulp (basis weight 200 g / m ² ) was used, and an intermediate layer core wrap sheet was used. An evaluation sample of Comparative Example 3 was prepared in the same manner as in Example 1 except that the sample was not used.

<Example 4>
A tissue as an intermediate sheet (basis weight 15 g / m ² , dynamic wetting index 0.175 seconds) was placed between the absorber and the moisture permeable back sheet, that is, between the diffusion sheet and the moisture permeable back sheet. A sample for evaluation of Example 4 was prepared in the same manner as in Example 1.

"Test method"
<Measurement of transpiration amount>
As shown in FIG. 11A, a hot plate 110 having a silicon rubber heater 112 with a sensor attached to the back surface of a plastic plate 111 having a width and length larger than that of the sample was prepared on the table 120. Next, the hot plate 110 is heated so that the plastic plate 111 of the hot plate 110 reaches 36 ° C., and the sample 130 is brought into contact with the plastic plate 111 of the hot plate 110 so that the surfaces of the moisture-permeable back sheets are in contact with each other. I put it on 110. Next, a plastic cylinder 140 having an inner diameter of φ60 mm was placed so as to overlap the absorber from above the sample 130. Then, 90 cc of artificial urine heated to 36 ° C. was dropped into the inside of the cylinder at intervals of 5 minutes at 30 cc once in 3 portions. After that, as shown in FIG. 11B, the sample 130 is turned over on the hot plate 110 and arranged so that the surface of the top sheet is in contact with the plastic plate 111 of the hot plate 110, and the peripheral edge of the sample is heated by the tape 150. It was attached to the plate 110 and sealed. The wiring of the silicon rubber heater 112 was removed from the hot plate 110, and the weights of the hot plate 110 and the sample 130 were measured with an electronic balance. The wiring of the silicon rubber heater 112 was attached to the hot plate 110 again, and the hot plate 110 was left to stand for 2 hours while being heated at 36 ° C. Then, the wiring of the silicon rubber heater 112 was removed from the hot plate 110, and the weights of the hot plate 110 and the sample 130 were measured with an electronic balance. The difference in weight between before and after leaving for 2 hours was measured three times, and the average value of the measured values was taken as the transpiration amount (g) in the sample 130.

The artificial urine used for this measurement was prepared by dissolving 200 g of urea, 80 g of sodium chloride, 8 g of magnesium sulfate, 3 g of calcium chloride and about 1 g of dye (Blue No. 1) in 10 L of ion-exchanged water.

<Measurement of moisture permeability of breathable back sheet>
Five square filter papers (No. 2 square qualitative filter paper manufactured by ADVANTECH) having a side of 100 mm were weighed and then stacked and placed on a plastic plate. The sample was placed on a plastic plate with the absorber overlapping the filter paper, and the periphery of the sample was taped to a hot plate for sealing. Next, a plastic cylinder having an inner diameter of φ60 mm was placed so as to overlap the absorber from above the sample. Then, 90 cc of artificial urine heated to 20 ° C. was dropped into the inside of the cylinder at intervals of 5 minutes at 30 cc once in 3 portions. Then, the tape on the peripheral edge of the sample was peeled off, five filter papers were taken out, and the weight thereof was measured. The difference in the weight of the filter paper before and after dropping the artificial urine was measured three times, and the average value of the measured values was taken as the amount of wetness (g) of the moisture-permeable backsheet in the sample.

<Measurement of temperature and absolute humidity inside tape-type diapers>
As shown in FIG. 12, a urination hole 220 that communicates with one surface of the heat plate 210 from the side surface of the heat plate 210 is provided, and a temperature / humidity sensor is provided on the surface of the heat plate 210 on the side where the urination hole 220 is located. The temperature / humidity sensor mounting tool 250 and the temperature / humidity sensor 230 were arranged so that the 230 was not in contact with the artificial urine dropped from the urination hole 220 and the sample 240. Next, the sample 240 was placed on the same surface so that the absorber overlapped the urination hole 220, and the peripheral edge of the sample 240 was sealed with tape. Next, the hot plate 210 was placed on the table so that the sample was on the lower side of the hot plate 210. Then, the hot plate 210 was heated to 36 ° C., and after the temperature was stabilized, artificial urine heated to 36 ° C. was poured from the urination hole 220 at 30 cc for 10 seconds. The temperature (° C.) and absolute humidity (g / cm ³ ) indicated by the temperature / humidity sensor 230 were measured 20 minutes after the artificial urine was poured. This was performed a total of three times, and the average value of the measured values was taken as the temperature (° C.) and absolute humidity (g / cm ³ ) in the sample 240 of each example.

《Evaluation》
The configuration of the tape-type diaper and the results of each test in each of the above examples are shown in Table 1 below.

As shown in Table 1, in each of the samples of Examples 1 to 4, the amount of transpiration was large and the amount of wetness of the back sheet was low as compared with Comparative Examples 1 and 2. Normally, as the amount of transpiration increases, it is considered that the amount of vapor discharged from the backsheet to the outside of the sample increases. Nevertheless, in the samples of Examples 1 to 4, it was possible to reduce the amount of wetness of the backsheet while increasing the amount of transpiration because the artificial urine that was not absorbed by the super absorbent polymer was able to reduce the amount of transpiration. The in-plane diffusion of the sample by the lower core wrap, which has a high Krem water absorption, increases the area of the backsheet where transpiration occurs, which increases the amount of transpiration from the entire backsheet while increasing the amount of transpiration of the backsheet. It is considered that this is because the amount of transpiration per unit area decreased.

Further, in the samples of Examples 1 to 4, since the amount of transpiration could be increased as compared with Comparative Examples 1 and 2, the temperature and the absolute humidity could also be lowered.

In the sample of Comparative Example 3, the amount of wetness of the back sheet was low, but the amount of transpiration was low, and the temperature and absolute humidity did not decrease sufficiently.

Therefore, in the absorbent articles having the same composition as the samples of Examples 1 to 4, it is considered that the temperature and absolute humidity inside the absorbent articles after excretion are likely to decrease due to the large amount of transpiration. Further, in the absorbent articles having the same structure as the samples of Examples 1 to 4, it is considered that the back sheet is less wet and dew condensation is less likely to occur even though the amount of transpiration is large.

1 Tape-

type diapers

10a, 10b, 10c, 10d, 10e, and 10'absorbent body 11 Top sheet 12 Absorbent 12a Absorbent core 12b Upper

core wrap sheet

12c and 12c' Lower core wrap sheet 13 Breathable back sheet 14 Non-woven fabric back Sheet 15 Intermediate sheet 30 Condensation 40 Excretion diffusion area

Claims

An absorbent article in which the absorbent core, the diffusion sheet, and the breathable back sheet are laminated in this order from the skin facing surface side to the skin non-facing surface side.
The absorption core is mainly composed of a super absorbent polymer.
The diffusion sheet is mainly composed of hydrophilic fibers and has a Krem water absorption of 100 mm or more, and the moisture-permeable back sheet has a moisture permeability of 1500 g / m 2 / 24h or more.
Absorbent article.
The absorbent article according to claim 1, wherein the moisture permeable back sheet has a moisture permeability of 3500 g / m 2 / 24h or less.
The absorbent article according to claim 1 or 2, wherein the diffusion sheet does not substantially contain a surfactant.
The absorbent article according to any one of claims 1 to 3, wherein the diffusion sheet has a hydrophilic fiber basis weight of 35 g / m 2 or more and a Krem water absorption of 130 mm or more.
The absorbent article according to any one of claims 1 to 4, wherein the hydrophilic fiber contains a rayon fiber having streaks along the direction in which the fiber extends on the surface.
The absorbent article has a longitudinal direction and a width direction.
The absorbent article according to any one of claims 1 to 5, wherein the diffusion sheet covers at least a part of at least one end in the longitudinal direction and the width direction of the absorbing core.
It has an absorbent core and an absorber having a core wrap sheet covering at least the skin non-opposing surface side of the absorbent core, and the diffusion sheet is the core wrap sheet.
The absorbent article according to any one of claims 1 to 6.
The absorbent article according to claim 7, wherein the bonding area between the diffusion sheet and the moisture permeable back sheet is more than 0.5 and 20.0% or less of the area of the diffusion sheet.
An intermediate sheet having a lower hydrophilicity than the diffusion sheet and having a dynamic wetting index of more than 0.0 seconds and 0.2 seconds or less is laminated between the diffusion sheet and the moisture permeable back sheet. , The absorbent article according to claim 7.
The absorbent article according to claim 9, wherein the bonding area between the diffusion sheet and the intermediate sheet is more than 0.5% and 20.0% or less of the area of the diffusion sheet.
It has an absorbent core and an absorber having a core wrap sheet covering at least the skin non-opposing surface side of the absorbent core, and the diffusion sheet is the absorbent core and the core wrap sheet. Arranged between,
The absorbent article according to any one of claims 1 to 6.
The absorbent article according to any one of claims 8 to 11, wherein the thickness of the absorber is 1.5 mm or more and 3.0 mm or less.
A non-woven fabric back sheet having a breathability in the thickness direction of 100 cm 3 / cm 2 · min or more and 4000 cm 3 / cm 2 · min or less is further laminated on the non-skin facing surface side of the moisture permeable back sheet. Item 2. The absorbent article according to any one of Items 1 to 12.
The absorption core has an excrement diffusion region extending in at least one direction in the plane and having a lower basis weight of the superabsorbent polymer than other parts of the absorption core. 13. The absorbent article according to any one of 13.