WO2018122939A1

WO2018122939A1 - Absorbent article

Info

Publication number: WO2018122939A1
Application number: PCT/JP2016/088794
Authority: WO
Inventors: 浩喜森; 麗子 ▲高▼島; 紗紀子渡邉
Original assignee: ユニ・チャーム株式会社
Priority date: 2016-12-26
Filing date: 2016-12-26
Publication date: 2018-07-05
Also published as: JPWO2018122939A1; JP6674968B2

Abstract

The purpose of the present invention to disperse body fluid discharged onto the widthwise center of an absorber so that the absorbent capacity of the absorber can be efficiently used. The disposable diaper (10) includes: an absorber (40) that has an absorbent core (40a) and a core wrap (40b); and a top sheet (50) that is disposed on a skin facing side of the absorber. The absorber includes: a center region (45) that is disposed in the widthwise center of the absorber and comprises a center absorbent layer (401); and side regions (45) disposed outside the center region in the width direction and comprising the center absorbent layer (401), a first side absorbent layer (402), and a second side absorbent layer (402). The top sheet is disposed spanning across the skin facing side of the center region and the skin facing side of the side regions. The core wrap has a density that is higher than the density of the top sheet. The side regions have a density that is higher than the density of the center region.

Description

Absorbent articles

The present invention relates to an absorbent article having an absorbent body having a central region and a side region disposed outside the central region in the width direction, wherein the density of the side region is higher than the density of the central region.

Patent Document 1 discloses an absorbent body in which a squeezed portion is formed on a side portion in the width direction of the absorbent body. Since the pressing part is formed by compressing the absorbent body in the thickness direction, the density of the area where the pressing part is formed is higher than the density of the area where the pressing part is not formed. The center of the absorbent body in the width direction is disposed opposite to the wearer's excretion opening when worn, and more body fluid is discharged as compared to the side part of the absorbent body in the width direction. At this time, since the density of the compressed portion located on the side portion in the width direction of the absorber is higher than the density in the center in the width direction of the absorber, the body fluid discharged to the center in the width direction of the absorber is the width of the absorber. Guided to the side of the direction.

Special table 2003-144492 gazette

In the absorbent article of Patent Document 1, when body fluid is repeatedly discharged or a large amount of body fluid is discharged, the compressed portion disappears due to swelling of the absorbent body, and the drawability of the body fluid may be reduced. For this reason, it is difficult for the body fluid to reach the side part in the width direction of the absorbent body, and the absorbent performance of the absorbent body may not be effectively utilized.

The present invention has been made in view of the above-described problems, and an object of the present invention is to diffuse body fluid discharged to the center in the width direction of the absorber and effectively utilize the absorption performance of the absorber.

An absorbent article (disposable diaper 10) according to the present disclosure includes a front-rear direction (front-rear direction L), a width direction (width direction W) orthogonal to the front-rear direction, an absorption core (absorption core 40a), and the absorption core. A core wrap (core wrap 40b) covering the skin, and a top sheet (top sheet 50) disposed on the skin-facing surface side of the absorber. A central region (central region 44) disposed in the center of the absorbent body in the width direction and having a central absorbent layer (central absorbent layer 401), disposed on both outer sides in the width direction of the central region, and the center A side region (side region 45) having an absorbent layer and a side absorbent layer (first side absorbent layer 402, second side absorbent layer 403) disposed on the skin-facing surface side of the central absorbent layer; The top sheet includes the center Is disposed across the skin facing surface side of the region and the skin facing surface side of the side region, the density of the core wrap is higher than the density of the top sheet, and the density of the side region is the The gist is that it is higher than the density of the central region.

It is a top view of the disposable diaper in one embodiment. FIG. 2 is a cross-sectional view of the disposable diaper along the line AA shown in FIG. 1. It is a top view of the absorber of a deployment state. FIG. 4 is a cross-sectional view of the absorber along the line BB in FIG. 3. It is sectional drawing which showed typically the cross section along the width direction of a top sheet and an absorber. It is sectional drawing which showed typically the wearing condition of a disposable diaper. It is sectional drawing of the disposable diaper in a modification. The table | surface which shows the penetration result of the absorbent article which concerns on Example 1, the comparative example 1, and the comparative example 2, the amount of rewet, the diffusibility of the core wrap on the skin opposing surface side, and the diffusibility of the core wrap on the non-skin opposing surface side It is.

At least the following matters will become apparent from the description of the present specification and the accompanying drawings.
Forward and backward,
A width direction orthogonal to the front-rear direction;
An absorbent body having an absorbent core and a core wrap covering the absorbent core;
A top sheet disposed on the skin-facing surface side of the absorber,
The absorber is disposed at the center in the width direction of the absorber and has a central region having a central absorbent layer, and is disposed on both outer sides in the width direction of the central region, and the central absorbent layer and the center. A side region having a side absorption layer disposed on the skin facing surface side of the absorption layer, and
The top sheet is disposed across the skin facing surface side of the central region and the skin facing surface side of the side region,
The density of the core wrap is higher than the density of the top sheet,
The density of the said side part area is an absorbent article higher than the density of the said center area | region.

When body fluid is discharged from the wearer, it is discharged to the skin facing surface side of the top sheet covering the central region. Only the central absorbent layer is disposed in the central region, and the central absorbent layer and the lateral absorbent layer are disposed in the side region. Therefore, the thickness of the absorber is relatively thin in the center region, and the center region is recessed on the non-skin facing surface side as compared with the side region. Since the central region is recessed toward the non-skin facing surface, a space extending in the front-rear direction can be formed between the wearer and the absorbent body. The body fluid can be diffused in the front-rear direction by the space, and it becomes easy to effectively utilize the absorption performance over the entire front-rear direction of the absorber.

Moreover, since the density of the core wrap is higher than the density of the top sheet, the body fluid is easily guided from the top sheet side to the absorber side (non-skin facing surface side). Therefore, body fluid can be drawn into the absorber side while diffusing in the front-rear direction, and it is easy to effectively utilize the absorption performance over the entire region in the thickness direction of the absorber. Since the density of the side region is higher than the density of the central region, the body fluid drawn into the central region is guided to the side region. The body fluid can be diffused in the width direction, and it becomes easy to effectively utilize the absorption performance over the entire width direction of the absorber.

Such an absorbent article,
The absorbent core has pulp and superabsorbent polymer;
The basis weight of the superabsorbent polymer in the side region is preferably higher than the basis weight of the superabsorbent polymer in the central region.

Since the basis weight of the superabsorbent polymer is relatively high, the side region tends to swell when absorbing body fluids. By swelling the side region, the volume of the space between the wearer and the absorbent body becomes larger, and body fluid continues to diffuse in the front-rear direction, making it easier to effectively utilize the absorption performance over the entire area in the front-rear direction of the absorbent body. .

Such an absorbent article,
The core wrap is preferably disposed on the skin facing surface of the central absorbent layer and the non-skin facing surface of the side absorbent layer in the side region.

In the side region, a plurality of core wraps are arranged so as to facilitate the body fluid to be guided from the central absorption layer side to the side absorption layer side. It becomes easy to effectively utilize the absorption performance over the entire region in the thickness direction of the absorber.

Such an absorbent article,
The length in the width direction of the side region is preferably equal to or greater than the thickness after absorbing the body fluid in the side region.

Even if the absorbent body is deformed when worn, the side absorbent layer and the central absorbent layer overlap because the length in the width direction of the side region is equal to or greater than the thickness after absorbing the body fluid in the side region. Easy to maintain.

Such an absorbent article,
The top sheet has a convex part and a concave part recessed on the non-skin facing surface side than the convex part,
It is desirable that the convex portion and the concave portion are arranged in a region extending in the front-rear direction and overlapping the central region.

The central area is recessed on the non-skin facing surface side than the side area. Therefore, the convex part and concave part which overlap with a center area | region are hard to be crushed by body pressure, and are easy to maintain the shape. By the convex part and concave part of the top sheet, the body fluid can be diffused in the front-rear direction, and it becomes easy to effectively utilize the absorption performance over the entire area in the front-rear direction of the absorbent body.

=== About the absorbent article which concerns on this Embodiment ===
Next, an embodiment of a disposable diaper as an absorbent article according to the present invention will be described with reference to the drawings. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. However, it should be noted that the drawings are schematic and ratios of dimensions and the like are different from actual ones. Accordingly, specific dimensions and the like should be determined in consideration of the following description. Moreover, the part from which the relationship and ratio of a mutual dimension differ also in between drawings may be contained.

(1) Whole schematic structure of disposable diaper FIG. 1: is a top view of the unfolded state of the disposable diaper 10 as an absorbent article which concerns on this embodiment. FIG. 2 is a cross-sectional view of the disposable diaper 10 taken along the line AA shown in FIG. FIG. 3 is a plan view of the absorbent body in a developed state. FIG. 4 is a cross-sectional view of the absorber taken along line BB shown in FIG. The plan view shown in FIG. 1 is a diagram in a state where the leg stretchable portion 75 and the elastic member 77 of the three-dimensional gather are extended until the top sheet 50 and the side sheets 70 constituting the disposable diaper are not formed with a heel. In addition, the absorbent article of this Embodiment is not restricted to a disposable diaper, An absorption pad may be sufficient.

The disposable diaper 10 has a front waistline region 20, a crotch region 25, and a back waistline region 30. The front waistline region 20 is a portion in contact with the wearer's front waistline portion (abdomen portion). Moreover, the back waistline area 30 is a part which contacts a wearer's back waistline part (back part). The crotch region 25 is a region that is located between the front waistline region 20 and the rear waistline region 30 and is provided with a leg opening 35. The leg opening 35 is provided at the outer edge of the disposable diaper, and is a portion that is disposed around the leg of the wearer while the disposable diaper is worn by the wearer. The outer edge is an outer end in the width direction, and the inner edge is an inner end in the width direction.

In this embodiment, the direction from the front waistline region 20 to the rear waistline region 30 is referred to as the front-rear direction L, the direction orthogonal to the front-rear direction L is referred to as the width direction W, and the skin facing surface side T1 of the wearer, The direction opposite to the skin facing surface side T1 and including the non-skin facing surface side T2 of the wearer is referred to as a thickness direction T.

The disposable diaper 10 has at least the absorber 40, the top sheet 50 arrange | positioned at the skin opposing surface side T1 of the absorber 40, and the non-skin surface sheet located in the non-skin opposing surface side T2 of the absorber 40. . The absorber 40 is disposed at least in the crotch region 25. The absorber 40 has the absorption core 40a and the core wrap 40b. The absorbent core 40a can be made of a material similar to that of a conventional disposable diaper, includes an absorbent material such as pulverized pulp or a superabsorbent polymer (SAP), and can be appropriately formed using a known member or material. The core wrap 40b is a sheet that covers the absorbent core 40a that is an absorbent material. The core wrap 40b is composed of various fiber nonwoven fabrics or tissues having liquid permeability. The core wrap 40b of the present embodiment has a basis weight of 16 g / m ² and is composed of a tissue having a density of 0.002 g / m ³ . The absorber 40 will be described in detail later. The top sheet 50 is formed of a liquid permeable sheet such as a nonwoven fabric or a woven fabric. The top sheet 50 is a sheet that comes into contact with the skin of the wearer. The top sheet 50 of the present embodiment has a basis weight of 27 g / m ² and is constituted by an air-through nonwoven fabric having a density of 0.0003 g / m ³ . In addition, you may provide the auxiliary sheet which improves the drawing property of a bodily fluid between the top sheet 50 and the absorber 40. FIG.

The density of the core wrap 40b is higher than the density of the top sheet 50. Since the density of the core wrap 40b is higher than the density of the top sheet 50, the body fluid is easily guided from the top sheet 50 side to the absorber 40 side (non-skin facing surface side). Therefore, body fluid can be drawn into the absorber 40 side while diffusing in the front-rear direction, and it is easy to effectively utilize the absorption performance over the entire area of the absorber 40 in the thickness direction. Moreover, it is difficult to transfer the body fluid from the core wrap to the top sheet side once drawn to the absorber side, the liquid return is reduced, and good rewetting can be obtained.

The density of the core wrap 40b and the density of the top sheet 50 correspond to the density of the fibers of the core wrap 40b and the density of the fibers of the top sheet 50. The basis weight and density of the sheet (core wrap, top sheet, etc.) and the absorbent body in the present embodiment can be measured, for example, by the following measuring method. Cut a sample of the same area from the object whose basis weight is to be measured. Next, the weight of the sample is measured, and the thickness of the cross section of the sample is measured with a microscope. The basis weight can be calculated by dividing each weight by the area, and the density can be calculated by dividing each weight by the volume (thickness × area).

Further, since the density of the core wrap 40b is higher than the density of the top sheet 50, the inter-fiber distance of the core wrap 40b is smaller than the inter-fiber distance of the top sheet 50. Since the inter-fiber distance of the core wrap 40b is smaller than the inter-fiber distance of the top sheet 50, the body fluid is easily guided from the top sheet 50 side to the absorber 40 side (non-skin facing surface side). In general, when the inter-fiber distance is large, a gap formed between the fibers is large, and body fluid is easily guided into the gap. Since the inter-fiber distance of the top sheet 50 is relatively large, body fluid quickly passes (permeates) in the thickness direction of the top sheet 50. On the other hand, when the interfiber distance is small, the gap formed between the fibers is small. In general, when the gap formed between the fibers is small, the interval between adjacent fibers is narrow, so that the body fluid spreads (diffuses) not only in the thickness direction but also in the plane direction through the adjacent fibers. Therefore, when the body fluid quickly passes through the top sheet 50 in the thickness direction and reaches the core wrap, the body fluid passes through the gap in the thickness direction and reaches the absorption core while diffusing in the plane direction. Therefore, the body fluid is easily guided from the top sheet 50 side to the absorber 40 side (non-skin facing surface side).

“Distance between fibers” can be used as an alternative value of fiber density, and can be measured, for example, by the following method. The inter-fiber distance of the fiber structure can be measured using a mercury porosimeter (manufactured by Shimadzu Corporation) or the like in accordance with the mercury intrusion method (JIS R 1655). In this mercury intrusion method, the pressure applied to mercury when mercury is injected between the constituent fibers of the fiber structure that is the object to be measured, and the volume of mercury pushed into the space between the constituent fibers of the fiber structure. By measuring the above, information on the structure of the fiber structure can be obtained. Specifically, it can be measured by the method described in paragraph 0036 of Japanese Patent Application No. 2014-209451.

The back sheet 60a has liquid impermeability and is disposed on the non-skin facing surface side T2 of the absorbent core 40a and the core wrap 40b. On the non-skin facing surface side T2 of the back sheet 60a, an exterior sheet 60 made of a nonwoven fabric is disposed.

The side sheet 70 covers the outer edge of the top sheet 50 and extends outside the top sheet 50 in the width direction W. The inner edge of the side sheet 70 is folded outward in the width direction W, and an elastic member 77 that expands and contracts in the front-rear direction is disposed between the two side sheets 70. The side sheet 70 and the elastic member 77 constitute a three-dimensional gather. A three-dimensional gather has the elastic member 77 which expands-contracts in the front-back direction, and is arrange | positioned by a pair on the both outer sides of the width direction rather than the center of the width direction of a disposable diaper.

The side sheet 70 is provided with a fastening tape 90. The fastening tape 90 extends along the width direction W in the rear waistline region 30 and is fastened to the target portion 95 of the front waistline region 20 to hold the disposable diaper 10 on the wearer's body. The target portion 95 is configured such that the pair of fastening tapes 90 are fixed to each other. On the outer side in the width direction of the absorber 40, there is provided a leg expansion / contraction portion 75 that is formed around the leg opening 35 and that can expand and contract in the front-rear direction L.

(2) Configuration of Absorber Next, the configuration of the absorber 40 will be described in detail. As shown in FIGS. 3 and 4, the absorber 40 is in the form of a single sheet in the unfolded state. The absorber 40 has a pair of first fold lines FL1 extending in the front-rear direction L and a pair of second fold lines FL2 extending in the front-rear direction L. The pair of first fold lines FL1 and the pair of second fold lines FL2 are fold lines for folding the absorber 40, and are formed in a state in which the absorber 40 is folded. The absorber 40 is folded at four locations by a pair of first fold lines FL1 and a pair of second fold lines FL2, and is laminated in a plurality of layers. The pair of first fold lines FL1, the pair of second fold lines FL2, and the first fold line FL1 and the second fold line FL2 are separated from each other in the width direction W. As shown in FIG. 3, the second fold line FL 2 is wider than the first fold line FL 1 in the unfolded state of the absorber 40 (the state where the absorber 40 is not folded by the first fold line FL 1 and the second fold line FL 2). Located outside W. As shown in FIG. 2, in the folded state of the absorber 40 (the state folded by the first fold line FL1 and the second fold line FL2), the second fold line FL2 is wider than the first fold line FL1 in the width direction W. Located inside.

In the folded state, the absorbent body 40 includes a central absorbent layer 401 located between the pair of first fold lines FL1 and a pair of first side parts located between the first fold line FL1 and the second fold line FL2. It has the absorption layer 402 and a pair of 2nd side part absorption layer 403 located in the outer side of the width direction W rather than 2nd fold line FL2. The 1st side part absorption layer 402 and the 2nd side part absorption layer 403 are arrange | positioned at the skin opposing surface side T1 of the center absorption layer 401, and comprise the side part absorption layer of this application. In the developed state shown in FIGS. 3 and 4, the central absorbent layer 401 is a region between the pair of first fold lines FL1 including the center of the absorbent body 40 in the width direction W. The first side absorption layer 402 is located on both sides of the central absorption layer 401 in the expanded state, and is a region between the first fold line FL1 and the second fold line FL2. The second side absorption layer 403 is located on both sides of the central absorption layer 401 and the pair of first side absorption layers 402 in the unfolded state, and is a region between the outer side in the width direction than the second fold line FL2. is there. The central absorption layer 401, the first side absorption layer 402, and the second side absorption layer 403 are continuous in the width direction W. The central absorbent layer 401, the first side absorbent layer 402, and the second side absorbent layer 403 are covered with one continuous core wrap 40b. The core wrap 40b straddles the central absorbent layer 401, the first side absorbent layer 402, and the second side absorbent layer 403.

The absorber 40 is valley-folded with respect to the wearer by the first fold line FL1, and is mountain-folded with respect to the wearer by the second fold line FL2. In the folded state in which the absorbent body 40 is folded, the first side absorbent layer 402 is disposed on the skin facing surface side T1 of the central absorbent layer 401, and the second side is disposed on the skin facing surface side T1 of the first side absorbent layer 402. A partial absorption layer 403 is disposed. The second side part absorption layer 403 should just be arrange | positioned at the skin opposing surface side T1 of the 1st side part absorption layer 402 at least partially. Since the absorber 40 is folded by the first fold line FL1 and the second fold line FL2, the dimension in the width direction W becomes compact.

In the folded state, the pair of second fold lines FL2 are separated in the width direction W. Only the central absorption layer 401 is disposed between the pair of second folding lines FL2. A region between the pair of second fold lines FL 2 constitutes a central region 44 that is disposed at the center in the width direction W of the absorber 40 and has the central absorbent layer 401. The region between the first fold line FL1 and the second fold line FL2 is disposed on both outer sides in the width direction W of the central region 44, and the central absorption layer 401, the first side absorption layer 402, and the second side portion. A side region 45 having the absorption layer 403 is formed. The absorber 40 has at least a central region 44 and a side region 45.

The thickness of the central region 44 is thinner than the thickness of the side region 45. In the present embodiment, the central region 44 has a thickness of 3.8 to 4.4 mm, and the side region 45 has a thickness of 5.0 mm to 5.4 mm. The center region 44 is recessed to the non-skin facing surface side T2 from the side region 45. The center region 44 is recessed to the non-skin facing surface side T2, and a space S1 extending in the front-rear direction L is formed between the wearer and the absorber 40. The body fluid discharged to the crotch region by the space S1 can be diffused in the front-rear direction L, and it is easy to effectively utilize the absorption performance over the entire front-rear direction of the absorber 40. When body fluid is guided from the central region 44 side to the side region 45 side, the inner edge (side portion on the central region 44 side) of the side region 45 swells as the body fluid is absorbed. The thickness difference between the side region 45 and the central region 44 becomes large, the volume of the space S1 can be secured, and the absorption performance can be more effectively utilized over the entire region in the front-rear direction of the absorber 40.

The outer edge of the second side absorption layer 403 is located outside the first fold line FL1 in the width direction W. Only the second side absorption layer 403 is disposed outside the first fold line FL1 in the width direction W. When a force is applied from the outer side in the width direction W toward the inner side in the width direction W, the second side absorption layer 403 located on the outermost side in the width direction is pressed inward in the width direction W. If the second side absorbent layer 403 is deformed so as to rise to the wearer side, the walls by the second side absorbent layer 403 can be provided relatively high on both sides of the central region 44. Therefore, lateral leakage of body fluid can be suppressed, and excrement leakage can be further suppressed.

Also, the outer edge 40E of the folded absorbent body 40 is disposed around the wearer's leg. The outer edge 40E of the absorber 40 is the outer edge of the second side absorbent layer 403. Only the second side absorption layer 403 is disposed on the outer edge 40E of the folded absorbent body 40 and is relatively thin. Therefore, the uncomfortable feeling around the wearer's leg can be reduced.

The basis weight of the absorbent material of the first side absorbent layer 402 is lower than the basis weight of the absorbent material of the central absorbent layer 401 and lower than the basis weight of the absorbent material of the second side absorbent layer 403. Specifically, the central absorbent layer 401 has pulp and SAP, and the first side absorbent layer 402 has substantially no absorbent material. The first side absorbent layer 402 has zero basis weight of the designed absorbent material such as SAP, but may have SAP or pulp mixed from the central absorbent layer or the like in the manufacturing process. The basis weight of the pulp of the central absorbent layer 401 and the basis weight of the pulp of the second side absorbent layer 403 are higher than the basis weight of the pulp of the first side absorbent layer 402. The 1st side absorption layer 402 may contain the pulp of the basic weight lower than the center absorption layer 401 grade | etc., May be comprised only by the core wrap 40b without including both a pulp and SAP, and is a comparison. Since the target basis weight is low, body fluid can be smoothly guided to the central absorbent layer 401 via the first side absorbent layer 402. In the modification, the basis weight of the absorbent material of the first side absorbent layer 402 may be the same as the basis weight of the absorbent material of the central absorbent layer 401, or the absorbent material of the second side absorbent layer 403. The basis weight may be the same.

Since the basis weight of the pulp of the 1st side part absorption layer 402 is low compared with the center absorption layer 401 and the 2nd side part absorption layer 403, it can suppress that the thickness of the side part area | region 45 becomes too thick, and non-skin facing It becomes easy to guide the body fluid to the central absorption layer 401 located on the surface side T2. In addition, since the basis weight of the pulp of the central absorbent layer 401 is higher than the basis weight of the pulp of the first side absorbent layer 402, body fluid can easily migrate from the first side absorbent layer 402 to the central absorbent layer 401. It becomes easy to guide the body fluid to the central absorbent layer 401 located on the skin facing surface side T2. The first fold line FL1 and the second fold line FL2 are formed with a difference in rigidity due to a difference in basis weight of the pulp. Therefore, it becomes easier to fold the absorber 40 based on the first fold line FL1 and the second fold line FL2.

The thickness of the 1st side part absorption layer 402 is thinner than the thickness of the center absorption layer 401, and is thinner than the thickness of the 2nd side part absorption layer 403. The first fold line FL1 and the second fold line FL2 are boundaries where the thickness and basis weight of the absorber 40 change, and are boundaries where the rigidity changes. Therefore, it is easy to fold the absorber 40 from the first fold line FL1 and the second fold line FL2.

The basis weight of the superabsorbent polymer in the side region 45 is higher than the basis weight of the superabsorbent polymer in the central region 44. The basis weight of the side region 45 is a total basis weight of the central absorbent layer 401, the first side absorbent layer 402, and the second side absorbent layer 403 stacked in the side region 455. Since the basis weight of the superabsorbent polymer is relatively high, the side region 45 is likely to swell when absorbing body fluid. As the side region 45 swells, the volume of the space between the wearer and the absorbent body becomes larger, the body fluid continues to diffuse in the front-rear direction, and the absorption performance is effectively utilized throughout the front-rear direction of the absorbent body 40. It becomes easy.

The basis weight of the pulp in the side region 45 is higher than the basis weight of the pulp in the central region 44. Since the basis weight of the pulp is relatively high, the side region 45 tends to be thick in a state before the body fluid is absorbed. Further, since the side area 45 has a high basis weight of SAP, it is likely to be thick even in a state after absorption of body fluid. Therefore, it is possible to continue to secure the volume of the space S1 extending in the front-rear direction between the wearer and the absorbent body, diffuse body fluid in the front-rear direction L, and effectively utilize the absorption performance over the entire area of the absorbent body 40 in the front-rear direction L. It becomes easy to do.

The density of the side region 45 is higher than the density of the central region 44. The density of the side region 45 in the present embodiment is 0.172 to 0.186 g / m ³ , and the density of the central region 44 is 0.106 to 0.122 g / m ³ . Since the density of the side region 45 is higher than the density of the central region 44, the body fluid drawn into the central region 44 is easily guided to the side region 45. The body fluid can be diffused in the width direction W, and it becomes easy to effectively utilize the absorption performance over the entire width direction of the absorber. In addition, the absorber 40 of this Embodiment is obtained by compressing to the thickness direction T in the state which has arrange | positioned the 1st side part absorption layer 402 and the 2nd side part absorption layer 403 on the center absorption layer 401. FIG. . The density can be measured by cutting out a sample from each of the central region 44 and the side region 45 and using the measurement method described above.

The length of the side region 45 in the width direction W is equal to or greater than the thickness of the side region 45 after absorbing the body fluid. Even if the absorbent body 40 is deformed at the time of wearing because the length in the width direction W of the side region 45 is not less than the thickness after absorbing the body fluid in the side region 45, the side absorption layer and the central absorption It is easy to maintain the state in which the layers overlap, and it is easy to continue to absorb body fluids that are repeatedly discharged. In addition, the thickness after absorbing the body fluid in the side region 45 is a thickness in a state where the absorber 40 has absorbed the maximum amount of body fluid. The length in the width direction W of the side region 45 and the thickness of the side region 45 after absorbing the body fluid is 8 mm.

In the side region 45, the core wrap 40b is disposed on the skin facing surface side T1 of the central absorbent layer 401 and the non-skin facing surface side T2 of the first side absorbent layer 402. In the side region 45, the core wrap 40b overlaps at least two layers. By arranging a plurality of core wraps 40b in the side region 45, body fluid can be easily guided from the central absorbent layer 401 side to the side absorbent layer side. It becomes easy to effectively utilize the absorption performance over the entire region of the absorber 40 in the thickness direction. In addition, the core wrap 40b of this Embodiment is laminated | stacked on four layers between the center absorption layer 401 and the 2nd side part absorption layer 403 of the side part area | region 45. FIG. Since a plurality of core wraps 40b having a relatively high density are stacked, it is possible to further improve the body fluid drawability from the top sheet 50 side to the absorber 40 side.

(3) Configuration of Top Sheet Next, the configuration of the top sheet 50 will be described in detail with reference to FIG. FIG. 5 is a cross-sectional view schematically showing a cross section along the width direction W of the top sheet 50 and the absorber 40. The top sheet 50 has a convex portion 52 and a concave portion 51. The recessed part 51 is recessed in the non-skin opposing surface side T2 rather than the convex part 52. FIG. The top sheet 50 has a ridge groove structure having a ridge composed of convex portions 52 and a groove composed of concave portions 51. The concave portion 51 and the convex portion 52 each extend in the front-rear direction L. The concave portions 51 are arranged with an interval in the width direction W, and the convex portions 52 are arranged with an interval in the width direction W. The concave portions 51 and the convex portions 52 are alternately arranged in the width direction W. In the present embodiment, “extending along the front-rear direction” may be a configuration having at least a certain range in the front-rear direction, and includes a configuration extending in the front-rear direction while being inclined with respect to the front-rear direction.

Since the top sheet 50 has the recessed part 51 and the convex part 52, and the center area | region 44 of the absorber 40 is dented in the non-skin opposing surface side T2, the space S1 extended in the front-back direction between a wearer and an absorber, and The body fluid can be diffused along the front-rear direction L by the unevenness of the top sheet. Moreover, the convex part 52 and the recessed part 51 which overlap with the center area | region 44 are hard to be crushed by body pressure, and are easy to maintain the shape. The bodily fluid can be diffused in the front-rear direction L by the convex portions 52 and the concave portions 51 of the top sheet 50, and it becomes easy to effectively utilize the absorption performance over the entire region of the absorber 40 in the front-rear direction.

The concave portion 51 is a portion where the basis weight of the fiber is lower than the average basis weight of the fiber of the top sheet 50, and the convex portion 52 is a portion where the basis weight of the fiber is higher than the average basis weight of the fiber of the top sheet 50. . The thickness T51 of the concave portion 51 is thinner than the thickness T52 of the convex portion 52. The density of the concave portions 51 is higher than the density of the convex portions 52. According to such a configuration, a difference in density occurs between the convex portion 52 and the concave portion 51. Due to this density difference, the body fluid quickly moves from the convex portion of the convex portion 52 to the concave portion 51. Therefore, it becomes easy to draw body fluid by the recessed part 51 of a top sheet, and can improve absorptivity.

The top sheet 50 is disposed across the skin facing surface side T1 of the central region 44 and the skin facing surface side T1 of the side region 45. The top sheet 50 extending in the width direction from the skin facing surface side T 1 of the central region 44 does not extend between the central absorbent layer 401 and the first side absorbent layer 402, but on the skin facing surface side T 1 of the side region 45. Extend. In the side region 45, the top sheet 50 is not disposed between the central absorbent layer 401 and the first side absorbent layer 402 and between the first side absorbent layer 402 and the second side absorbent layer 403. According to such a structure, when the force which goes to the inner side of the width direction W is applied to the side part area | region 45, it becomes difficult to move a side part absorption layer to the inner side of the width direction W, and deformation | transformation of the absorber 40 is effective. Can be suppressed. Further, the folded structure of the absorber 40 can be maintained, and excreta can be efficiently absorbed and excreted by the three absorption layers of the central absorption layer 401, the first side absorption layer 402, and the second side absorption layer 403. Leakage of things can be suppressed. Further, since the top sheet 50 is disposed across the central region 44 and the side region 45 and is not caught between the central absorbent layer 401 and the side absorbent layer, the density of the top sheet 50 in the planar direction of the top sheet 50 It is difficult for the difference to occur, and urine can be prevented from staying locally on the surface or inside of the top sheet 50. In addition, at the boundary between the central region 44 and the side region 45, a space S2 surrounded by the skin facing surface of the central region 44, the skin facing surface of the side region 45, and the top sheet 50 is formed. The body fluid can be temporarily held or the body fluid can be diffused in the front-rear direction.

(4) Joining Mode of Absorbers and Joining Mode of Absorbers and Non-Skin Surface Sheet Next, a joining mode of absorbers and a bonding mode of the absorber and non-skin sheet will be described. The disposable diaper 10 is provided with a first joining portion R1, a second non-joining portion NR2, a third joining portion R3, and a third non-joining portion NR3 in a folded state where the absorber 40 is folded. (See FIG. 6). Each joint is a region where an adhesive such as a hot-melt adhesive is disposed, and each non-joint is bonded more than a region where no adhesive such as a hot-melt adhesive is disposed, or a joint. This is an area where the adhesive is disposed so that the force is weakened. By having the first joint portion R1, the second non-joint portion NR2, the third joint portion R3, and the third non-joint portion NR3, the unintended deformation of the disposable diaper 10 at the time of wearing is suppressed, and excrement leaks. Can be suppressed. FIG. 6 is a cross-sectional view schematically illustrating a wearing state of the disposable diaper. When the disposable diaper 10 is attached to the wearer, the disposable diaper 10 is sandwiched between the wearer's legs. The disposable diaper 10 is applied with a force from the outside in the width direction W toward the inside in the width direction W. At this time, since the outer edge of the second side absorption layer 403 is located outside the first fold line in the width direction, the force from the outer side in the width direction toward the inner side in the width direction is the second side absorption layer 403. On the outside edge of the. The 2nd side part absorption layer 403 absorbs the force which goes to the inner side of the width direction from the outer side of the width direction by changing. Therefore, the central absorbent layer 401 can be prevented from being deformed by the force.

The first joint portion R1 is a portion where the skin facing surface of the central absorbent layer 401 and the non-skin facing surface of the first side absorbent layer 402 are joined. The first joint R1 may be provided on the entire surface where the skin-facing surface of the central absorbent layer 401 and the non-skin-facing surface of the first side absorbent layer 402 face each other, or on a part of the facing surface. It may be provided. When the first joint R1 is provided, when a force is applied to the disposable diaper 10 from the outer side in the width direction toward the inner side in the width direction, the central absorbent layer 401 and the first side absorbent layer 402 are disposed. Is prevented from shifting, and the folding structure by the first folding line FL1 is easily maintained. Therefore, unintended deformation of the central absorbent layer 401 and the entire absorbent body can be prevented from entering the width, and the absorbent body 40 can be arranged with a constant width with respect to the wearer's crotch. Excrement can be absorbed by the absorber 40 having a certain width, and the leakage of excrement can be suppressed.

The second non-joint portion NR2 is a portion where the skin facing surface of the first side absorbent layer 402 and the non-skin facing surface of the second side absorbent layer 403 are not joined in the wearing state. The second non-joint portion NR2 is provided on the entire surface where the skin facing surface of the first side absorption layer 402 and the non-skin facing surface of the second side absorption layer 403 face each other at least in the crotch region 25. The second non-joined portion NR2 extends across the center of the disposable diaper 10 in the front-rear direction and extends in the front-rear direction in the crotch region 25. The second non-joining portion NR2 of the present embodiment is a region where no adhesive is disposed, and is in a non-joined state even in the folded state. In the folded state, the second non-joint portion NR2 is joined to the skin facing surface of the first side absorbent layer 402 and the non-skin facing surface of the second side absorbent layer 403, and is worn and outside in the width direction. The structure which will be in a non-joining state earlier than a 1st junction part when the force which goes to the inner side of the width direction is applied may be sufficient. Since the skin facing surface of the first side absorbent layer 402 and the non-skin facing surface of the second side absorbent layer 403 are not joined in the crotch region 25 when worn, the force is directed from the outside in the width direction to the inside in the width direction. The second side absorption layer is deformed so that the left and right second side absorption layers 403 rise to the wearer side with the first side absorption layer 402 joined to the central absorption layer 401 as a starting point. A space S3 is formed on the non-skin facing surface side T2 of the layer 403. Excrement can be held by the space S3 between the first side absorption layer 402 and the second side absorption layer 403, and leakage of excrement can be suppressed.

The third joint portion R3 is a portion where the second side absorption layer 403 and the non-skin surface sheet are joined. More specifically, in the third joint portion R3, the non-skin facing surface of the second side absorption layer 403 and the skin facing surface of the back sheet 60a as the non-skin surface sheet are joined. The range in the front-rear direction L of the second side absorption layer 403 is the entire region in the front-rear direction L of the absorber 40. The range of the third joint R3 in the width direction W is a certain range extending from the outer edge of the second side absorption layer 403 to the inside of the width direction W. The third joint portion R3 is located outside the first fold line FL1 in the width direction W and is separated from the first fold line FL1. A third non-joining portion NR3 is provided on the inner side in the width direction W than the third joining portion R3. The third non-joint portion NR3 is a portion where the second side absorption layer 403 and the non-skin surface sheet are not joined. The third non-joining portion NR3 straddles the center in the front-rear direction of the disposable diaper 10 and extends in the front-rear direction L in the crotch region 25. The third non-joining part NR3 is inside the width direction W from the third joining part R3 and outside the width direction W from the first fold line FL1. In the region on the inner side in the width direction from the first fold line FL1, the central absorbent layer 401 and the back sheet 60a are joined.

2nd side part absorption layer 403 and back sheet 60a are joined by the 3rd joined part R3, and are not joined by the 3rd non-joined part NR3. Therefore, when a force is applied from the outer side in the width direction W to the inner side in the width direction W, the absorbent body 40 that comes into contact with the third non-joint portion NR3 with the third joint portion R3 as a base point rises to the wearer side. The space S4 that is deformed and is surrounded by the second side absorbent layer 403, the back sheet 60a, and the central absorbent layer 401 can be provided at least in the crotch region 25 (see FIG. 6). Urine can be accommodated in the space S4. Moreover, urine can be diffused in the front-rear direction L by the space S4, and body fluid can be retained in the entire region of the absorber 40 in the front-rear direction L. Therefore, even if it is a case where it is used for a long time, a body fluid can be absorbed with the absorber 40 whole, and the leakage of a body fluid can be suppressed. In addition, moisture can be diffused in the front-rear direction L by the space S4, and stuffiness can be suppressed and the wearing feeling can be improved.

The third joint R3 is disposed in a region overlapping the inner edge of the elastic member 77. In the configuration in which the three-dimensional gather has a plurality of elastic members, the inner edge of the elastic member 77 is the inner edge of the elastic member located on the innermost side in the width direction. The inner edge of the elastic member 77 of the three-dimensional gather contracts due to the expansion and contraction of the elastic member 77 and stands on the wearer side. The absorber in the region overlapping the inner edge of the elastic member 77 is joined to the backsheet 60a by the third joint R3 and is not easily deformed. Therefore, when the three-dimensional gather contracts, the shape of the absorber 40 is easily maintained, and the three-dimensional gather is easily raised from the absorber 40 toward the wearer. Therefore, the space which accommodates excrement can be provided widely between the solid gathers and the absorber 40, and leakage of excrement can be suppressed. As a result, excrement leakage can be effectively suppressed while the folded structure of the absorber 40 is maintained.

(5) Absorbent article according to modification Next, a disposable diaper 10A as an absorbent article according to the modification will be described with reference to FIG. In the description of the modification, the same reference numerals are used for the same configurations as those in the embodiment, and the description is omitted. FIG. 7: is sectional drawing of the cross section along the width direction of 10 A of disposable diapers which concern on a modification. In the absorbent body 40 of the disposable diaper 10A according to the modification, the central absorbent layer 401 and the side absorbent layer 404 are not integrated, and are configured separately. Moreover, the side part absorption layer 404 is one layer. The central region 44 is a region where only the central absorbent layer 401 is disposed, and the side region 45 is a region where the central absorbent layer 401 and the side absorbent layer 404 are disposed.

Also with the disposable diaper 10A according to the modification, a space extending in the front-rear direction can be formed between the wearer and the absorbent body. The body fluid can be diffused in the front-rear direction by the space, and it becomes easy to effectively utilize the absorption performance over the entire front-rear direction of the absorber. Further, the density of the side region 45 is higher than the density of the central region 44, and the body fluid drawn into the central region 44 is guided to the side region 45. The body fluid can be diffused in the width direction, and it becomes easy to effectively utilize the absorption performance over the entire width direction of the absorber.

(6) Example Next, comparative evaluation will be described with respect to the absorbent performance of absorbent articles with different core wraps. Using the absorbent article according to Example 1 and the absorbent articles according to Comparative Examples 1 and 2, the permeation rate, the rewet amount, and the diffusibility were evaluated. In addition, the absorbent article which concerns on Example 1, and the absorbent article which concerns on the comparative example 1 and the comparative example 2 are the same except the structure of a core wrap. The core wrap of Example 1 is arrange | positioned at the skin opposing surface side and non-skin opposing surface side of the absorption core, and is comprised with the tissue of density 0.002g / m < ³ >, respectively. The core wrap of the comparative example 1 is arrange | positioned at the skin opposing surface side and non-skin opposing surface side of the absorption core, and is comprised with the SMS nonwoven fabric of density 0.0009g / m < ³ >, respectively. The absorbent article of Comparative Example 2 does not have a core wrap. The density of the top sheet is 0.0003 g / m ³ .

“Penetration” means the ease with which the liquid excretion supplied on the skin-facing surface side surface of the top sheet 50 spreads from the skin-facing surface side to the non-skin-facing surface side. Then, the liquid excrement is quantitatively evaluated by the time (ie, “bake rate”) required for the liquid excrement to burn from the surface on the skin facing surface side of the top sheet 50 toward the non-skin facing surface side and disappear from the top sheet 50. be able to.

The permeation rate was calculated by adding 40 ml, 80 ml, and 120 ml of simulated urine once onto the top sheet 50 of the absorbent article of the evaluation test sample, and transferring all the simulated urine into the top sheet 50 (seconds). Measure and use the measured time as the penetration rate (seconds). Next, the time (seconds) in which the simulated urine passes through the top sheet 50 and moves all to the absorber side is measured, and this measured time is defined as the speed of speed (seconds). The simulated urine is 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 a pigment (blue No. 1) in 10 L of ion-exchanged water.

The amount of rewet was measured with filter paper (Advantech Toyo Qualitative Filter Paper No. 2,100 mm × 5%) at the place where the artificial urine was dropped 5 minutes after the start of dripping in the state where the simulated urine moved to the absorber side when measuring the permeation rate. (100 mm) 50 g was placed on top of each other, and a weight was placed thereon so that the pressure was 35 g / cm ² . After 3 minutes, the filter paper was taken out and the “rewetting amount” was calculated according to the following formula. The smaller the amount of rewet, the less liquid return and the better rewet.
Rewetting amount (g) = filter paper mass after test (g) −initial filter paper mass (g)

The diffusibility of the sheet can be evaluated by, for example, the sheet crepe water absorption measured in accordance with JIS P8141 “Paper and paperboard—Water absorption test method—Clem method”. Klem water absorbency is the height at which the lower end of the test piece is vertically immersed in water and the water rises for 10 minutes by capillary action. high.

FIG. 8 shows the penetration rate, rewetting amount, core wrap diffusivity on the skin facing surface side, and core wrap diffusivity on the non-skin facing surface side of the absorbent articles according to Example 1, Comparative Example 1 and Comparative Example 2. .

The absorbent article according to Example 1, the absorbent article according to Comparative Example 1, and the absorbent article according to Comparative Example 2 were not significantly different in terms of penetration rate. However, the absorbent article according to Example 1 had a small amount of rewet, and in particular 120 ml with a large amount of absorption, good results were obtained compared to the comparative example. Moreover, the absorbent article which concerns on Example 1 obtained the high numerical value with the diffusibility of the core wrap by the side of a skin opposing surface, and the diffusibility of the core wrap by the side of a non-skin opposing surface. The absorptive article concerning Example 1 obtained a high numerical value especially in the diffusibility of 80 ml and 120 ml with many absorptions, and was able to obtain a good result also about the diffusivity of body fluid.

As described above, the contents of the present invention have been disclosed through the embodiments of the present invention. However, it should not be understood that the descriptions and drawings constituting a part of this disclosure limit the present invention. From this disclosure, various alternative embodiments, examples, and operational techniques will be apparent to those skilled in the art. Therefore, the technical scope of the present invention is defined only by the invention specifying matters according to the scope of claims reasonable from the above description.

It is possible to provide an absorbent article capable of diffusing body fluid discharged in the center in the width direction of the absorbent body and effectively utilizing the absorbent performance of the absorbent body.

10, 10A: Disposable diaper 20: Front waistline area 25: Inseam area 30: Rear waistline area 40: Absorbent body 40a: Absorbent core 40b: Core wrap 401: Central absorbent layer 402: First side absorbent layer 403: Second side part Absorbing layer 44: Central region 45: Side region 50: Top sheet 51: Concave portion 52: Convex portion 60: Exterior sheet 60a: Back sheet L: Back and forth direction T: Thickness direction W: Width direction FL1: First fold line FL2: 2nd folding line R1: 1st junction part NR2: 2nd non-joining part R3: 3rd junction part NR3: 3rd non-joining part

Claims

Forward and backward,
A width direction orthogonal to the front-rear direction;
An absorbent body having an absorbent core and a core wrap covering the absorbent core;
A top sheet disposed on the skin-facing surface side of the absorber,
The absorber is disposed at the center in the width direction of the absorber and has a central region having a central absorbent layer, and is disposed on both outer sides in the width direction of the central region, and the central absorbent layer and the center. A side region having a side absorption layer disposed on the skin facing surface side of the absorption layer, and
The top sheet is disposed across the skin facing surface side of the central region and the skin facing surface side of the side region,
The density of the core wrap is higher than the density of the top sheet,
The density of the said side part area is an absorbent article higher than the density of the said center area | region.
The absorbent core has pulp and superabsorbent polymer;
The absorbent article according to claim 1, wherein the basis weight of the superabsorbent polymer in the side region is higher than the basis weight of the superabsorbent polymer in the central region.
3. The absorbent article according to claim 1, wherein the core wrap is disposed on the skin facing surface of the central absorbent layer and the non-skin facing surface of the side absorbent layer in the side region.
The absorbent article according to any one of claims 1 to 3, wherein a length of the side region in the width direction is equal to or greater than a thickness after the body fluid in the side region is absorbed.
The top sheet has a convex part and a concave part recessed on the non-skin facing surface side than the convex part,
The said convex part and the said recessed part are absorbent articles in any one of Claims 1-4 extended in the said front-back direction and arrange | positioned in the area | region which overlaps with the said center area | region.