TWM477876U - Absorbent article - Google Patents

Abstract

An absorbent member (13) of an absorbent article (10) has an absorbent core (16) and a core-wrap sheet (17). The absorbent core (16) has a first surface having a high content ratio of superabsorbent polymer and a second surface located on the opposite side of the first surface and having a high content ratio of pulp fiber. The absorbent core (16) has a first surface thereof located on the skin-facing surface and a second surface thereof located on the side of the non-skin-facing surface. A topsheet (11) has an uneven structure formed at least on the surface facing the absorbent member (13), so that spaces are formed between the topsheet (11) and the absorbent member (13) due to the uneven structure. The first surface (16a) of the absorbent core (16) in the absorbent member (13) and the core-wrap sheet (17) are intermittently joined along the width direction by a plurality of bonded regions (18) extending along the longitudinal direction Y.

Description

Absorbent article

This creation is about absorbent articles such as disposable diapers or menstrual napkins.

There are known various techniques in which an absorbent article of an absorbent article is composed of pulp fibers and superabsorbent polymer particles, and the superabsorbent polymer particles are biased to one side in the thickness direction of the absorbent body. For example, Patent Document 1 discloses that the density of the superabsorbent material in the first half portion including the first main plane side in the absorber is higher than the high absorption in the second half portion including the opposite second main surface. The density of the material. The first main plane faces the skin contact surface side in the absorbent article.

Patent Document 2 describes an absorbent article in which a superabsorbent polymer is mixed in the absorbent body, and one or all of the superabsorbent polymer is disposed on the surface layer side. Further, in this document, it is described that an absorbent body in which the superabsorbent polymer is biased to one side is used in combination with a front sheet which is provided with uneven embossing.

In addition, in order to efficiently absorb the liquid throughout the entire absorbent body, various methods have been proposed in which the liquid is diffused in the direction of the surface of the absorbent body to effectively utilize the absorption area. For example, it is known that a sub-layer sheet in which a liquid is easily diffused in the surface direction is disposed on the skin contact surface side of the absorbent body. Further, there is also known a technique in which a groove is formed in an absorber or a compression process is performed to diffuse a liquid to the entire body of the absorber. On the other hand, however, the diffusion of the liquid throughout the entire body of the absorbent body increases the area in which the skin is in contact with the liquid, or the humidity in the space between the absorbent article and the skin in the worn state rises. In the above patent documents, it is not used to increase the diffusion of liquid into the direction of the surface of the absorber and to eliminate the occurrence of A good way to conduct research.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. Hei 6-205806

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2007-117727

The present invention provides an elongated absorbent article comprising a front sheet positioned on the side of the wearer's skin, a back sheet on the side remote from the wearer's skin, and the front sheet and the back sheet The absorber between them has a length direction and a width direction orthogonal thereto.

The absorber has an absorbent core and a core material covering the absorbent core.

The above absorbent core system is a mixture of pulp fibers and a highly absorbent polymer. The absorption rate of the superabsorbent polymer is 30 seconds or more and 150 seconds or less. The absorbent core has a first surface having a high ratio of the superabsorbent polymer and a second surface located on the opposite side of the first surface and having a higher ratio of the pulp fibers.

The absorbent core system is disposed such that the first surface thereof is located on the skin contact surface side and the second surface is located on the non-skin contact surface side.

The front sheet has an uneven structure on at least the opposing surface side of the absorber. A space due to the uneven structure is formed between the front sheet and the absorber.

In the above-mentioned absorber, the first surface of the absorbent core and the package core material are intermittently joined in the width direction in a plurality of subsequent regions extending in the longitudinal direction.

10‧‧‧Disposable diapers

11‧‧‧Front sheet

11a‧‧‧1st protrusion

11b‧‧‧2nd protrusion

11c‧‧‧ Space

11d‧‧‧ space

12‧‧‧Back sheet

13‧‧‧Acceptor

14‧‧‧Leak-proof cuffs

14a‧‧‧Sheet

14b‧‧‧Flexible components

14c‧‧‧Flexible components

15‧‧‧ leg cuffs

16‧‧‧Absorbing core

16a‧‧‧Upper surface

17‧‧‧Package

18‧‧‧Next area

19‧‧‧ Non-continuous area

20‧‧‧Binder

111‧‧‧1st

112‧‧‧2nd

A‧‧‧ ventral side

B‧‧‧Back side

C‧‧‧胯下下

F‧‧‧Buckle belt

L‧‧‧Fixed tape

N‧‧‧Liquid

W‧‧‧Width

X‧‧‧Width direction

Y‧‧‧ Length direction

Z‧‧‧ Thickness direction

Fig. 1 is a perspective view showing a disposable diaper as an embodiment of the present invention.

Fig. 2 is an enlarged view of a main part of a front sheet in the diaper shown in Fig. 1.

Figure 3 is a cross-sectional view showing the main portion of the lower portion of the diaper shown in Figure 1 in the width direction Surface map.

Fig. 4 is a plan view showing the state of adhesion of the absorbent core and the packaged core material in the diaper shown in Fig. 1.

Fig. 5 (a) to (d) are schematic views showing the state of diffusion and absorption of the liquid in the diaper shown in Fig. 1.

Hereinafter, the present invention will be described with reference to the drawings based on preferred embodiments thereof. Fig. 1 shows a disposable diaper as an embodiment of the absorbent article of the present invention. Figure 2 is a longitudinal sectional view of the lower portion of the crucible in Figure 1. The disposable diaper 10 shown in the figure is a fixed type of unfolded type. The diaper 10 has a longitudinal direction Y and a width direction X orthogonal thereto, and has a shape elongated in the longitudinal direction Y. The central portion of the diaper 10 in the longitudinal direction Y becomes the crotch portion C. The crotch portion A and the back side portion B are formed before and after the crotch portion C.

The diaper 10 includes a front sheet 11 located on the side close to the skin of the wearer, that is, on the skin contact surface side, and a back sheet 12 located on the side of the skin that is away from the wearer, that is, on the non-skin contact surface side. The absorber 13 is located between the front sheet 11 and the back sheet 12.

The left and right sides of the diaper 10 in the width direction X have one pair of leak-proof flanges 14, 14 extending in the longitudinal direction Y. The leak-proof cuff 14 extends over the entire length of the diaper 10. The leak-proof cuff 14 includes one of the longer sheets Y in the longitudinal direction Y folded in the longitudinal direction Y. The leakage preventing flange 14 has a free end and a fixed end along the length direction Y. The free end is along the portion of the fold line of the folded sheet 14a. The elastic member 14b such as a rubber thread is disposed and fixed to the free end in an extended state. The elastic member 14b is disposed at least in the crotch portion C. By shrinking the elastic member 14b, the leakage preventing flange 14 has a tendency to stand up toward the skin side of the wearer. The fixed end of the leakage preventing flange 14 is joined to the back sheet 12 extending laterally from the left and right side edges of the absorber 13. By this joining, the leg cuffs 15 are formed on the left and right side portions of the diaper 10. At the leg cuffs 15, at the portion where the fixed end of the leak-proof cuff 14 is joined to the back sheet 12, the elastic member 14c such as a rubber thread is disposed and fixed between the two in an extended state. The elastic member 14c is disposed at least at Lower part C. By contracting the elastic member 14c, in the worn state of the diaper 10, the leg cuffs 15 are in close contact with the leg circumference of the wearer.

In the diaper 10, a pair of fastening tapes F and F are provided on the left and right side edges of the back side portion B. A fixing tape L for fixing the fastening tapes F and F is provided on the outer surface of the abdominal portion A, that is, the non-skin contact surface of the back sheet 12. The wearing state of the diaper 10 is completed by fixing the fastening tape F to the fixing tape L.

As the front sheet 11, a sheet having liquid permeability is used. Details of the sheet are described below. As the back sheet 12, a film which is liquid impermeable or liquid-impermeable, or a non-woven fabric (for example, a spunbond-meltblown-spun non-woven fabric) can be used. As the sheet 14a constituting the leak-proof cuff 14, a water-repellent sheet, for example, various non-woven fabrics represented by a spunbonded nonwoven fabric can be used.

An enlarged view of a main portion of the front sheet 11 is shown in Fig. 3 . The front sheet 11 has a concavo-convex structure on each side thereof. The front sheet 11 has a configuration that is continuous in the plane direction thereof. "Continuous" means an uninterrupted part or a small hole. However, micropores such as pores between fibers are not included in the above pores.

The front sheet 11 has a first surface 111 and a second surface 112. The first surface 111 is in contact with the surface of the wearer's skin. The second surface 112 is opposed to the absorber 13 . On the first surface 111 side of the front sheet 11, the plurality of first protruding portions 11a are arranged in an in-plane oblique relationship in two directions of the vertical and horizontal directions (hereinafter, the arrangement may be referred to as a diagonal lattice arrangement). ). In some cases, the lattice arrangement may be orthogonal (90°). In this case, the arrangement is divided into orthogonal grid-like arrangements. In the present embodiment, it is preferable that any of the first directions in the plane intersects with the second direction orthogonal thereto at an angle of 30 to 90 degrees. Further, in the present embodiment, a plurality of protruding second projections 11b are formed on the second surface 112 side of the front sheet 11. The second protruding portions 11b are also arranged in a diagonal lattice shape, but may be arranged in an orthogonal lattice shape. The preferable range of the intersecting angle depends on the first protruding portion 11a, and therefore is the same as described above. The first protruding portion 11a and the second protruding portion 11b protrude in opposite directions from each other with respect to the sheet surface. And both They are alternately arranged regardless of whether they are in the same position in a plan view or in a side view, that is, without overlapping.

In the above-described manner, the first projecting portion 11a and the second projecting portion 11b which are arranged to extend in the first direction and the second direction in the plane are formed in a planar shape without any contradiction, and constitute the front sheet 11. Here, the non-contradictory continuous means that when a specific shape portion is joined to form a surface, it does not bend or become discontinuous, and the entire surface is continuous with a gentle curved surface. In addition, the arrangement form of the first protruding portion 11a and the second protruding portion 11b is not limited to the one shown in FIG. 2, and may be in a form that can be arranged in a continuous arrangement without contradiction. For example, it is also possible to arrange the six second protruding portions 11b at the apex of the hexagon around the first protruding portion 11a and to expand the pattern in the plane. In this case, the number of the second protruding portions 11b exceeds the number of the first protruding portions 11a, and thus the second protruding portions 11b are adjacent to each other. However, as long as the overall continuous sheet state is formed, such a state The arrangement of the forms is also included in the meaning that the first protruding portion 11a and the second protruding portion 11b are alternately arranged.

The first projecting portion 11a and the second projecting portion 11b are formed in a truncated cone shape or a hemispherical shape having a curved top portion. More specifically, the protruding shape of the first protruding portion 11a is not sharp, but is not hemispherical. On the other hand, the protruding shape of the second protruding portion 11b is sharper and has a curved conical or truncated cone shape at the top. However, the shape of each of the protruding portions 11a and 11b is not limited thereto, and may be any protruding form. For example, it is actually various pyramid shapes (in the present specification, the cone shape widely includes the meanings of a cone, a truncated cone, a pyramid, a truncated cone, a tapered cone, and the like).

The first projecting portion 11a and the second projecting portion 11b hold the space 11c, 11d having a truncated cone shape or a hemispherical shape which is similar in shape to the top portion. Each of the spaces 11c and 11d is partitioned by the front sheet 11, and is formed into a substantially discontinuous space.

In the present embodiment, when the front sheet 11 is viewed in a plan view, the first protruding portion 11a and the second protruding portion 11b are formed so as to be in a staggered arrangement in a zigzag pattern. That is, the protruding portions 11a, 11b are arranged in such a manner that, in a plan view of the front sheet 11, The first protruding portion 11a and the second protruding portion 11b alternately appear in the first direction in the plane, and the first protruding portion 11a and the second protruding portion 11b also alternately appear in the second direction orthogonal to the first direction. The topsheet 11 having such a structure can be preferably produced by, for example, using various fiber materials as a raw material, and by the method described in Japanese Laid-Open Patent Publication No. 2012-136792.

Since at least the facing surface side of the front surface sheet 11 has a concavo-convex structure on the opposite surface side of the absorber 13, the diaper 10 is formed between the front sheet 11 and the absorber 13 by the uneven structure as shown in FIG. A plurality of spaces 11d are generated. With this space 11d, the front sheet 11 and the absorber 13 are discontinuously spaced apart in the plane direction. This space 11d functions as a temporary storage space for the liquid when the liquid discharged to the front sheet 11 passes through the front sheet 11, thereby suppressing the diffusion of the liquid in the surface direction. The diffusion of the liquid temporarily stored in the space 11d in the direction of the surface is suppressed and absorbed into the absorption layer 13.

The apparent thickness of the front sheet 11, that is, the length from the vertex position of the first protruding portion 11a to the vertex position of the second protruding portion 11b is preferably 1 mm or more from the viewpoint of forming a temporary storage space of a sufficient volume. It is preferably 1.5 mm or more, and preferably 4.5 mm or less, and particularly preferably 4.2 mm or less. For example, the apparent thickness of the front sheet 11 is preferably 1 mm or more and 4.5 mm or less, and more preferably 1.5 mm or more and 4.2 mm or less. The apparent thickness of the front sheet 11 was measured in a state where a pressure of 0.05 kPa was applied to the front sheet 11. On the other hand, the thickness of the front sheet 11 itself is preferably 0.1 mm or more, more preferably 0.2 mm or more, further preferably 2 mm or less, and particularly preferably 1.5 mm or less. For example, the thickness of the front sheet 11 itself is preferably 0.1 mm or more and 2 mm or less, and more preferably 0.2 mm or more and 1.5 mm or less.

The absorber 13 includes an absorbent core 16 and a core material 17 covering the absorbent core 16. The packaged core material 17 covers the entire surface of at least the upper surface of the absorbent core 16, that is, the entire surface of the skin abutting surface of the facing sheet. Further, it is preferable that the packaged core material 17 covers the entire surface of the lower surface of the absorbent core 16, that is, the entire surface of the non-skin contact surface of the opposite surface of the back sheet.

The absorbent core 16 is composed of a pulp fiber and a superabsorbent polymer. Absorb In the core 16, the pulp fibers and the superabsorbent polymer are stacked in a mixed state. The pulp fibers and the superabsorbent polymer are not uniformly distributed in the thickness direction Z of the absorbent core 16, and the distribution state of the two is biased to one side. Specifically, in the thickness direction Z of the absorbent core 16, the absorbent core 16 has a first surface having a high ratio of a highly absorbent polymer, and a ratio of the pulp fibers on the opposite side of the first surface. The second side is higher. Further, the absorbent core 16 is disposed such that the first surface thereof is located on the skin contact surface side and the second surface is located on the non-skin contact surface side.

Regarding the superabsorbent polymer in the absorbent core 16, the ratio of the presence of the superabsorbent polymer in the thickness direction Z to the absorbent core 16 is the highest. Further, the superabsorbent polymer is applied to the non-skin contact surface of the absorbent core 16 and has the lowest ratio of existence. Between the skin contact surface and the non-skin contact surface, the ratio of the presence of the superabsorbent polymer decreases from the contact surface of the skin to the non-skin contact surface. The manner of reduction can be, for example, continuously decreasing gradually, or can be reduced stepwise in a discontinuous manner.

On the other hand, regarding the pulp fibers, the ratio of the presence of the pulp fibers to the non-skin contact surface of the absorbent core 16 in the thickness direction Z is the highest. Further, the skin abutting surface of the absorbent core 16 has the lowest ratio of existence. Between the contact surface of the skin and the non-skin contact surface, the ratio of the presence of the pulp fibers decreases from the non-skin contact surface to the skin contact surface. The manner of reduction can be, for example, continuously decreasing gradually, or can be reduced stepwise in a discontinuous manner.

As described above, in the absorbent core 16, the superabsorbent polymer is biased to the skin contact surface side, and on the other hand, the pulp fibers are biased to the non-skin contact surface. By using the absorbent core 13 having the structure of the absorbent core 16 in a specific follow-up pattern in combination with the coated core material 17 and the front sheet 11 having the above-described uneven structure, the skin contact surface side can be suppressed. The liquid diffuses and allows the liquid to spread largely on the non-skin contact surface side. Details of this mechanism are described below.

The superabsorbent polymer in the thickness direction Z of the absorbent core 16 and the degree to which the pulp fibers are biased to one side, on the abutting surface of the skin and the vicinity thereof, the superabsorbent polymer The ratio is preferably 60% by mass or more, more preferably 65% by mass or more, and is preferably 95% by mass or less, and particularly preferably 90% by mass or less. On the other hand, the ratio of the pulp fibers is preferably 5% by mass or more, more preferably 10% by mass or more, and particularly preferably 40% by mass or less, and particularly preferably 35% by mass or less. For example, the ratio of the superabsorbent polymer in the skin contact surface and the vicinity thereof is preferably 60% by mass or more and 95% by mass or less, and more preferably 65% by mass or more and 90% by mass or less.

The above-mentioned skin contact surface and the vicinity thereof refer to a portion on the skin contact surface side of the portion where the thickness of the absorber is divided into two. On the other hand, the non-skin contact surface and the vicinity thereof refer to a portion on the non-skin contact surface side of the portion where the thickness of the absorber is divided into two. The ratio of the highly absorbent polymer and the pulp fiber in the skin contact surface and the vicinity thereof and the non-skin contact surface and the vicinity thereof were measured by the following methods.

The absorbent body was cut into a length of 3 cm in the longitudinal direction. The cut portion was held by two acrylic plates. At this time, the gap gauge having the same thickness as the thickness of the absorber is placed between the acrylic sheets so as not to overlap the absorber, and the thickness is maintained while being held. Then, the blade of the cutter is used to divide the absorber into two in the thickness direction. The skin contact surface and the vicinity thereof separated by the split surface and the non-skin contact surface and the vicinity thereof are respectively placed in a mesh bag composed of a material having no water retention, so as to be non-absorbent In the manner in which the polymer is detached, the following operations are performed for each mesh bag. First, each part is weighed (this value is set to (A)). Next, each part was immersed in physiological saline for 30 minutes. Thereafter, each part was pulled up from the physiological saline solution, and suspended for 10 minutes, and the water was removed by natural dropping. Then, each part was subjected to moisture removal by a centrifugal dehydrator for 10 minutes at a speed of 800 rpm. The amount of water in each part held by the centrifugal dehydrator after moisture removal is determined (this value is (B)) (hereinafter, the amount of water retained after removal of water by the centrifugal dehydrator is referred to as "centrifugation retention amount" ").

On the other hand, weigh the polymer of the same type as the superabsorbent polymer contained in each part, put it into a mesh bag, and perform the same operation as above to obtain only high absorbency. The centrifuge retention of the polymer. Then, the centrifugal retention amount (C) per 1 g of the superabsorbent polymer was calculated.

Using the values of A, B, and C obtained by the above operation, the amount (D) of the superabsorbent polymer in each part is calculated based on the calculation of {(B)-(A)}÷(C), and further The ratio of the superabsorbent polymer was determined from (D) ÷ (A). In addition to this, the ratio of the pulp fibers was determined from {(A) - (D)} ÷ (A).

The ratio of the superabsorbent polymer to the non-skin contact surface of the absorbent core 16 and the vicinity thereof is preferably 30% by mass or more, more preferably 35% by mass or more, and particularly preferably 55% by mass or less. Preferably, it is 50% by mass or less. On the other hand, the ratio of the pulp fibers is preferably 45% by mass or more, more preferably 50% by mass or more, and particularly preferably 75% by mass or less, and particularly preferably 70% by mass or less. For example, the ratio of the superabsorbent polymer in the non-skin contact surface and the vicinity thereof is preferably 30% by mass or more and 55% by mass or less, and more preferably 35% by mass or more and 50% by mass or less. On the other hand, the ratio of the pulp fibers in the non-skin contact surface and the vicinity thereof is preferably 45 mass% or more and 75 mass% or less, and more preferably 50 mass% or more and 70 mass% or less.

The basis weight of the superabsorbent polymer in the absorbent core 16 is preferably 30 g/m ² or more, and more preferably 50 g/m ² or more. The upper limit is preferably 350 g/m ² or less, and particularly preferably 300 g/m ² or less. For example, the basis weight of the superabsorbent polymer is preferably 30 g/m ² or more and 350 g/m ² or less, and more preferably 50 g/m ² or more and 300 g/m ² or less. On the other hand, the basis weight of the pulp fibers in the absorbent core 16 is preferably 30 g/m ² or more, and particularly preferably 50 g/m ² or more. The upper limit is preferably 300 g/m ² or less, and particularly preferably 250 g/m ² or less. For example, the basis weight of the pulp fiber is preferably 30 g/m ² or more and 300 g/m ² or less, and more preferably 50 g/m ² or more and 250 g/m ² or less.

The ratio of the superabsorbent polymer to the pulp fiber in the absorbent core 16 is preferably 1 or more, more preferably 1.2 or more, and preferably 2 or less, in terms of a mass ratio of [superabsorbent polymer/pulp fiber]. Yu Jia is 1.8 or less. By absorbing the superabsorbent polymer in the core 16 The ratio of the amount of each of the pulp fibers and the ratio of the pulp fibers is set to the above range, and it is not necessary to excessively thicken the absorbent core 16 to ensure a sufficient liquid holding capacity.

The basis weight of the absorbent core 16 itself is preferably 60 g/m ² or more, and particularly preferably 70 g/m ² or more. The upper limit is preferably 650 g/m ² or less, and particularly preferably 600 g/m ² or less. For example, the basis weight of the absorbent core 16 is preferably 60 g/m ² or more and 650 g/m ² or less, and more preferably 70 g/m ² or more and 600 g/m ² or less.

The superabsorbent polymer contained in the absorbent core 16 is preferably a liquid which can absorb and maintain a liquid which is 20 times or more of its own weight and which is gellable. The shape is not particularly limited and may be, for example, spherical, massive, grape-like, powdery or fibrous. It is preferably a particle having a size of 1 μm or more and 1000 μm or less, more preferably 10 μm or more and 500 μm or less. Examples of such a superabsorbent polymer include starch or croscarmellose, a polymer or copolymer of acrylic acid or an alkali metal acrylate, polyacrylic acid and a salt thereof, and polyacrylate salt graft polymerization. Things. As the polyacrylate, a sodium salt can be preferably used. Further, a copolymer obtained by using maleic acid, itaconic acid, acrylamide, 2-propenylamine-2-methylpropanesulfonic acid, 2-(methyl) in acrylic acid is preferably used. Comonomers such as acrylonitrilesulfonic acid, 2-hydroxyethyl (meth)acrylate or styrenesulfonic acid are copolymerized in a range that does not degrade the performance of the superabsorbent polymer.

As the pulp fiber contained in the absorbent core 16, the same as those previously used for such an absorbent article can be used. For example, fluff pulp can be used. The pulp fibers can also crosslink the cellulose constituting them as needed. Alternatively, the pulp fibers can also be crimped.

The packaged core material 17 covering the absorbent core 16 is used to improve the shape retention of the absorbent core 16. As the packaged core material 17, a liquid-permeable fibrous sheet can be used. For example, a tissue or a non-woven fabric can be used. As the nonwoven fabric, for example, a spunbonded nonwoven fabric, a spunbond-meltblown-spunbond (SMS) nonwoven fabric, a hot air non-woven fabric, a water needle nonwoven fabric, or the like can be used. The package core material 17 on the skin contact surface side of the cover absorbent core 16 and the package core material 17 on the non-skin contact surface side may be of the same type, or may be of different types.

As shown in FIG. 3, the upper surface of the absorbent core 16 and the packaged core material 17 covering the upper surface are intermittently followed by the adhesive 20. By this, the shape retention of the absorbent core 16 is further improved. Further, the latter also helps to control the diffusion of the liquid on the upper surface of the absorbent core 16 into the thickness direction Z and the diffusion in the direction of the surface.

FIG. 4 shows the pattern of the skin contact surface and the non-skin contact surface of the absorbent core 16 and the subsequent pattern of the packaged core material 17. As shown in the figure, the upper surface of the absorbent core 16 and the plurality of strip regions 18 extending in the longitudinal direction Y of the clad core material 17 are joined by the adhesive 20. A non-contiguous region 19 is formed between the adjacent regions 18 adjacent in the width direction X. That is, the adjacent regions 18 adjacent in the width direction X are separated by the non-adjacent regions 19. Thus, the upper surface of the absorbent core 16 is joined to the coated core material 17 in the continuous region 18 in the longitudinal direction Y, and intermittently joined in the width direction X via the non-adjacent region 19.

In the embodiment shown in Fig. 4, a plurality of subsequent regions 18 including the adhesive 20 formed in a plurality of rows and formed in a spiral shape are formed. However, the application pattern of the adhesive 20 is not limited to a spiral shape, and for example, the adhesive 20 may be applied in a stripe shape with a specific width. Alternatively, the adhesive 20 may be applied in an Ω-shaped coating pattern. Further, in the embodiment shown in Fig. 4, the region 18 is formed over the entire length Y of the absorbent core 16, or alternatively, the region 18 is extended only in one of the longitudinal directions Y of the absorbent core 16. Formed by the way. For example, the subsequent region 18 may be formed to extend only in a substantially central region of the longitudinal direction Y of the absorbent core 16.

By the upper surface of the absorbent core 16 being bonded to the packaged core material 17 in a specific pattern, if the liquid that has passed through the front surface 11 reaches the packaged core material 17, the liquid mainly passes through the non-adjacent region 19 in the packaged core material 17. The inner core of the absorbent core 16 is diffused in the surface of the absorbent core 16 in the surface direction. The reason for this is that the succeeding region 18 is less likely to transmit liquid than the non-adjacent region 19, thereby suppressing the diffusion of the liquid in the surface of the upper surface of the absorbent core 16 in the plane direction. In summary, if the liquid reaches the absorbent core 16, the diffusion of the liquid on the upper surface thereof in the surface direction is suppressed, and the liquid diffuses in the surface direction in the absorbent core 16. This situation is related to the following Advantageous Effects: It helps to reduce the transfer or liquid return of the liquid temporarily absorbed by the absorbent core 16 to the skin.

From the viewpoint of making the above effects further remarkable, the ratio of the area of the upper surface of the absorption core 16 to the area of the succeeding region 18 of the packaged core material 17 and the area of the non-adjacent area 19 is [the area of the area 18/non-adjacent area. The area of 19 is preferably 0.5 or more, and more preferably 0.6 or more. Further, the ratio is preferably 1.2 or less, and more preferably 1 or less. For example, the ratio is preferably 0.5 or more and 1.2 or less, and more preferably 0.6 or more and 1 or less.

From the viewpoint of further enhancing the above effects, the width of the non-adjacent region 19 is preferably set to 8 mm or more, and more preferably set to 10 mm or more. A plurality of the above-mentioned succeeding regions 18 are applied and the non-adjacent regions 19 are formed at regular intervals between the subsequent regions 18, whereby the liquid from the front sheet 11 to the absorbent body 13 is not hindered, and the diffusion of the liquid in the longitudinal direction is easily promoted. Further, the width of the non-adjacent region 19 is preferably 30 mm or less, and more preferably 25 mm or less. For example, the width of the non-adjacent region 19 is preferably 8 mm or more and 30 mm or less, and more preferably 10 mm or more and 25 mm or less. In addition, the area of the following region 18 refers to the area of the region where the adhesive 20 is actually applied when the adhesive 20 is applied in a stripe shape having a specific width to form the succeeding region 18. On the other hand, when the adhesive 20 is applied spirally as shown in FIG. 4 or when it is applied in an Ω-shape (not shown), the end of the adhesive 20 in the width direction X is formed. The product of the length W (see Fig. 4) and the length of the subsequent region 18 is defined as the area of the junction.

The fact that the upper surface of the absorbent core 16 and the packaged core material 17 are intermittently followed by the following regions has the advantage that the diffusion of the liquid in the plane direction can be suppressed even when the liquid is repeatedly absorbed. Specifically, when the absorbent core 16 temporarily absorbs the liquid, the superabsorbent polymer contained therein is swollen. Due to this swelling, a space is created between the absorbent core 16 and the packaged core material 17 disposed on the upper surface thereof. In this case, the degree of space generated by the non-joining region 19 becomes larger as compared with the joint region 18. After the second pass through the space When the liquid is collected, the liquid is smoothly transmitted, so that the diffusion of the liquid in the surface direction is suppressed.

The above description is the relationship between the upper surface of the absorbent core 16 and the packaged core material 17, and the lower surface of the absorbent core 16 and the packaged core material 17 are as shown in Fig. 4, along the length of the absorbent core 16. The stripping-like adhesive 20 is applied in an extended manner. Furthermore, the subsequent pattern of the adhesive 20 is not limited to the pattern shown in FIG. 4, and other patterns may be employed. Further, depending on the case, the lower surface of the core 16 and the packaged core material 17 may not be subsequently absorbed.

Referring to Figs. 5(a) to 5(d), a liquid permeation absorption mechanism in the diaper according to the embodiment having the above configuration will be described. Fig. 5(a) shows a state in which the liquid N has just been drained to the diaper 10. In this state, the liquid N is stored in the concave portion of the skin facing surface side including the front sheet 11 having the uneven structure and the entire apparent thickness of the space 11d.

Fig. 5(b) shows a state in which the liquid N passes through the topsheet 11 and moves from the skin contact surface side of the front sheet toward the opposite surface side of the absorber. In this state, the liquid N is temporarily stored in the space 11d partitioning between the package sheet material 17 formed in the front sheet 11 and the absorber 13. Since the space 11 is discontinuously formed in the plane direction, the diffusion of the liquid N in the plane direction is suppressed.

The liquid temporarily stored in the space 11d is then passed through the packaged core material 17 as shown in Fig. 5(c). As described above, the packaged core material 17 is followed by the upper surface 16a of the absorbent core 16 by the adhesive 20. In this succeeding region, the permeation of the liquid N is suppressed. In particular, as shown in Fig. 4, the following region is provided with a plurality of strips along the longitudinal direction of the diaper 10, so that the diffusion of the liquid N in the plane direction is suppressed by the respective succeeding regions. As a result, the liquid N mainly passes through the non-adjacent region between the subsequent regions, and is transmitted without being excessively diffused in the plane direction.

As shown in Fig. 5(d), the liquid N that has passed through the core material 17 and reaches the absorbent core 16 is permeated by the superabsorbent polymer which is biased on the upper surface 16a side of the absorbent core 16 or the skin abutting surface side. between. The superabsorbent polymer has a slower liquid absorption rate than the pulp fiber, so the superabsorbent polymer does not absorb in the state immediately after the liquid N is in contact with the superabsorbent polymer. The liquid N is collected, so the liquid N is directly transmitted downward. Further, since the superabsorbent polymer is biased to the skin contact surface side of the absorbent core 16, the liquid N is prevented from diffusing in the surface direction due to the presence of the superabsorbent polymer before the liquid swell. As a result, the liquid N is inside the absorbent core 16 and is transmitted toward the back sheet 12 side without excessive diffusion in the surface direction. Then, the liquid N is diffused in the direction of the lateral direction of the opposite surface of the back sheet in the absorbent core 16. As a result of the permeation absorption of the liquid, the diaper 10 of the present embodiment effectively reduces the transfer or liquid return to the skin. Further, the humidity in the space between the diaper 10 and the skin is lowered. Further, it is possible to efficiently dissipate heat or water vapor to the outer boundary of the non-skin contact surface. When the water vapor is dispersed in the case where the back sheet 12 is moisture permeable, the heat dissipation becomes more conspicuous.

The absorption rate of the superabsorbent polymer is preferably 30 seconds or more, more preferably 40 seconds or more, and preferably 150 seconds or less, and particularly preferably 120 seconds or less, from the viewpoint of further enhancing the above advantageous effects. For example, the absorption speed is preferably 30 seconds or more and 150 seconds or less, and more preferably 40 seconds or more and 120 seconds or less. By allowing the superabsorbent polymer to have an absorption speed in this range, it is possible to delay the time before the superabsorbent polymer on the skin contact surface side of the absorbent core 16 starts to absorb the liquid, so that the liquid easily permeates through the absorbent core 16. On the other hand, the liquid is easily diffused in the surface direction on the opposite surface side of the back sheet 12. In order to obtain a superabsorbent polymer having an absorption speed in this range, for example, the particle diameter of the absorbent polymer, the primary crosslink density, the degree of surface cross-linking adjustment (post-crosslinking treatment), shape control, and various The surface treatment of the surfactant such as the surfactant, the polyol, or the hydrophilic powder may be adjusted.

Further, the superabsorbent polymer preferably has a centrifugal retention amount in accordance with JIS K 7223 of 25 g/g or more, more preferably 30 g/g or more, and preferably 65 g/g or less, and particularly preferably 55 g/g or less. . For example, the amount of centrifugation is preferably 25 g/g or more and 65 g/g or less, and more preferably 30 g/g or more and 55 g/g or less. By allowing the superabsorbent polymer to have a centrifugal retention amount in this range, the degree of swelling of the superabsorbent polymer after absorbing the liquid is increased, thereby The passage of the liquid in the absorbent core 16 can be ensured. In order to obtain a superabsorbent polymer having a centrifugal retention amount in this range, for example, it is only necessary to adjust the degree of surface crosslinking of the absorbent polymer. In general, when the surface cross-linking degree of the absorbent polymer becomes high (the surface cross-linking treatment progresses), the centrifugal retention amount (water absorption ratio) tends to decrease. Specifically, for example, the amount of the surface crosslinking agent can be adjusted, or the surface crosslinking treatment temperature can be lowered, or the reaction time can be shortened, and the amount of centrifugal retention can be adjusted.

Further, the superabsorbent polymer preferably has a liquid permeation rate under pressure of 20 ml/min or more, more preferably 40 ml/min or more, and is preferably 1000 ml/min or less, and particularly preferably 800 ml/min or less. For example, the liquid permeation rate under pressure is preferably 20 ml/min or more and 1000 ml/min or less, and more preferably 40 ml/min or more and 800 ml/min or less. By allowing the superabsorbent polymer to have a liquid permeation rate under pressure in this range, even if the body pressure of the wearer is applied to the absorbent core 16, the liquid permeation path can be ensured between the superabsorbent polymers. . In order to obtain a highly absorbent polymer having a liquid permeation rate under pressure in this range, for example, it may be adjusted by the strength of crosslinking (internal crosslinking, and optionally surface crosslinking), shape, surface treatment, and the like.

The absorption rate of the above-mentioned superabsorbent polymer can be measured by the vortex method described in [0050] of JP-A-2010-017536. The amount of the centrifugal retention can be measured by the method described in [0047] of JP-A-2010-017536. The liquid permeation rate under pressure can be measured by the method described in [0008] to [0016] of JP-A-2003-235889.

As described above, the diaper 10 of the present embodiment has a liquid diffusion area which is significantly different from the skin contact surface side of the absorbent body 13 and the non-skin contact surface side. For example, the ratio of the liquid diffusion area on the skin contact surface side of the absorbent body 13 to the liquid diffusion area on the non-skin contact surface side is [the liquid diffusion area on the skin contact surface side/the liquid diffusion area on the non-skin contact surface side). It is preferably 0.5 or more, more preferably 0.55 or more, and is preferably 0.8 or less, and particularly preferably 0.75 or less. For example, the ratio is preferably 0.5 or more and 0.8 or less, and more preferably 0.55 or more. Below 0.75.

The above diffusion area was measured in the following manner. A specific position of the sample which was developed into a plane was set as a liquid injection point, and a specific amount (40 g) of the colored liquid was injected at a rate of 5 g/sec using a pump, and allowed to stand for 10 minutes. Thereafter, the front sheet is peeled off, and the colored regions on the packaged core material of the first surface of the absorbent core are overwritten onto the OHP sheet. The sample was turned over, the back sheet was peeled off, and the packaged substrate was gently peeled off, and the colored areas on the coated core material of the second side of the absorbent core were overwritten onto the OHP sheet. The image of the OHP sheet was taken into the scanner, and the diffusion area was calculated using Image Analysis Software Image-Pro Plus (manufactured by NIPPON ROPER).

As the liquid used for the measurement of the above diffusion area, for example, artificial urine is used. The composition of artificial urine is 1.94% by mass of urea, 0.795% by mass of sodium chloride, 0.11% by mass of magnesium sulfate, 0.062% by mass of calcium chloride, 0.197% by mass of potassium sulfate, 0.010% by mass of red No. 2 (dye), and 96.88 mass of water. % and polyoxyethylene lauryl ether (about 0.07 mass%), and the surface tension was adjusted to 53 ± 1 dyne / cm (23 ° C).

The present invention has been described based on the preferred embodiments thereof, but the present invention is not limited to the above embodiments. For example, in the above embodiment, each surface of the front sheet 11 has a concavo-convex structure. Alternatively, only the opposing surface of the absorber of the top sheet 11 may have a concavo-convex structure.

Further, the above embodiment is an example in which the absorbent article of the present invention is applied to a stretchable disposable diaper having a fixed type, but the present invention can also be applied to other forms of absorbent articles such as pants-type disposable diapers and incontinence. Pads, menstrual napkins, etc.

Regarding the above embodiment, the present invention further discloses the following absorbent article.

<1> An absorbent article comprising a front sheet located on a side close to a wearer's skin, a back sheet located on a side away from the wearer's skin, and between the front sheet and the back sheet An absorbent article having an absorbent body having a longitudinal direction and a width direction orthogonal thereto, and The absorbent body comprises an absorbent core body and a coated core material covering the absorbent core, wherein the absorbent core system is obtained by mixing pulp fibers and a superabsorbent polymer, and the absorption rate of the superabsorbent polymer is 30 seconds or more and 150 seconds. Hereinafter, the absorbent core includes a first surface having a high ratio of the superabsorbent polymer and a second surface located on a side opposite to the first surface and having a higher ratio of pulp fibers, wherein the absorbent core system The first surface is disposed on the skin contact surface side, and the second surface is disposed on the non-skin contact surface side. The front sheet has at least an uneven structure on the opposite surface side of the absorber, and the front sheet is provided on the front sheet. A space created by the uneven structure is formed between the absorber, and the first surface of the absorbent core and the plurality of subsequent regions extending in the longitudinal direction of the sheath core in the width direction are formed in the absorber. Intermittently joined.

The absorbent article according to the above <1>, wherein the mass ratio of the [superabsorbent polymer/the pulp fiber] in the absorbent core is 1 or more and 2 or less.

The absorbent article according to the above <1>, wherein the superabsorbent polymer in the absorbent core has a basis weight of 30 g/m ² or more and 350 g/m ² or less, and the pulp fiber is The basis weight is 30 g/m ² or more and 300 g/m ² or less.

The absorbent article according to any one of the above-mentioned items, wherein the superabsorbent polymer has a centrifugal retention amount of 25 g/g or more and 65 g/g or less in accordance with JIS K 7223. The liquid permeation rate under pressure is 20 ml/min or more and 1000 ml/min or less.

The absorbent article according to any one of the above aspects, wherein the ratio of the area of the first surface of the absorbent core to the area of the succeeding region of the packaged core material and the area of the non-adjacent area is [ The area of the area/area of the non-adjacent area is expressed as 0.5 or more and 1.2 or less, and the width of the non-subsequent area is 8 mm or more.

<6> The absorbent article according to the above <5>, wherein the width of the non-adjacent region is 30 Below mm.

The absorbent article according to any one of the above aspects, wherein the ratio of the liquid diffusion area on the skin contact surface side of the absorbent body to the liquid diffusion area on the non-skin contact surface side is [ The liquid diffusion area on the skin contact surface side and the liquid diffusion area on the non-skin contact surface side are expressed as 0.5 or more and 0.8 or less.

The absorbent article according to any one of the above-mentioned items, wherein the front sheet and the absorbent body are discontinuously spaced apart in the surface direction by the space.

The absorbent article according to any one of the above aspects, wherein the front sheet comprises a first surface that abuts against the skin of the wearer and a second surface that faces the absorbent body, and On the first surface side, the plurality of first protruding portions are arranged to extend in the in-plane oblique relationship in two directions of the vertical and horizontal directions, and any of the first directions in the plane and the second direction oblique thereto are 30° or more. Angles below 90° intersect.

The absorbent article according to any one of the above aspects, wherein the front sheet comprises a first surface that abuts against the skin of the wearer and a second surface that faces the absorbent body, and a plurality of first protrusions are arranged on the first surface side, and a plurality of second protrusions are arranged on the second surface side, and the first protrusions and the second protrusions face each other with respect to the sheet surface of the front sheet. The opposite directions are protruded, and the two protruding portions are formed to be alternately arranged in a non-overlapping relationship regardless of whether they are in the same position in a plan view or in a side view.

<11> The absorbent article according to the above <10>, wherein the first protruding portion and the second protruding portion are arranged in such a manner that six second protruding portions are disposed at the apex of the hexagon with the first protruding portion as a center. The pattern is expanded in-plane.

<12> The absorbent article according to the above <10>, wherein the protruding shape of the first protruding portion is hemispherical, and the protruding shape of the second protruding portion is sharp and the top has a curved conical or truncated cone shape.

The absorbent article according to any one of the above aspects, wherein the length from the vertex position of the first protruding portion to the vertex position of the second protruding portion is 1 mm or more and 4.5 mm or less.

The absorbent article according to any one of the above-mentioned items, wherein the coated core material covers the entire surface of the facing sheet of the absorbent core and covers the back sheet of the absorbent core. The whole face.

The absorbent article according to any one of the above aspects, wherein the ratio of the presence of the superabsorbent polymer in the absorbent core to the skin abutment surface in the thickness direction of the absorbent core is Between the non-skin contact surface and the non-skin contact surface, the contact surface from the skin contact surface is continuously reduced or discontinuously stepped.

The absorbent article according to any one of the above-mentioned items, wherein the ratio of the presence of the pulp fibers in the absorbent core to the skin abutting surface and the non-skin in the thickness direction of the absorbent core Between the abutting surfaces, the abutting surface of the skin is continuously reduced from the non-skin contact surface, or is discontinuously stepped.

The absorbent article according to any one of the above aspects, wherein the ratio of the superabsorbent polymer to the skin contact surface of the absorbent core and the vicinity thereof is 60% by mass or more. 95% by mass or less, the ratio of the pulp fibers is 5% by mass or more and 40% by mass or less.

The absorbent article according to any one of the above-mentioned items, wherein the amount of the superabsorbent polymer in the absorbent core is 30 g/m ² or more and 350 g/m ² or less, and the pulp fiber is The amount is 30 g/m ² or more and 300 g/m ² or less.

The absorbent article according to any one of the above-mentioned items, wherein the coated core material comprises a liquid-permeable fibrous sheet comprising a tissue or a non-woven fabric, the nonwoven fabric comprising Spunbonded non-woven fabric, spunbond-meltblown-spunbond (SMS) non-woven fabric, hot air non-woven fabric or water needle non-woven fabric.

<20> The absorbent article according to any one of the above <1> to <19> wherein A spin coating, a stripe shape, or an Ω-shaped coating pattern is applied to the adhesive to form the above-described succeeding regions.

The absorbent article according to any one of the items <1> to <20> which has a longitudinal direction Y and a width direction X orthogonal thereto, and has a long shape in the longitudinal direction Y, and a longitudinal direction Y The central region becomes the lower part of the lower jaw, and the lower part of the lower part becomes the ventral side and the back side.

<22> The absorbent article according to the above <21>, wherein the left and right sides in the width direction X have one pair of leak-proof cuffs extending in the longitudinal direction Y, and the leak-proof cuffs extend over the entire length of the absorbent article. The extension and the leakage preventing flange comprise a pair of sheets which are longer in the longitudinal direction Y and are folded in the longitudinal direction Y. The leakage preventing flange has a free end and a fixed end along the longitudinal direction Y, and the free end is along the opposite side. The elastic member is disposed and fixed to the free end in an extended state at a portion of the fold line of the sheet.

<23> The absorbent article according to the above <22>, wherein the left and right side portions are formed with a leg cuff, and the leg portion is cuffed, and the elastic end portion is joined to the back sheet at the fixed end of the leak preventing cuff. The member is fixed between the two in an extended state.

<24> The absorbent article according to any one of <1> to <23> which is a disposable diaper.

<25> The absorbent article according to the above <24>, which is a strap-type unfolded disposable diaper.

<26> The absorbent article according to the above <25>, wherein a pair of fastening tapes are provided on the left and right side edges of the back side portion, and a fixing tape for fixing the fastening tape is provided on the outer surface of the abdominal side portion.

<27> The absorbent article according to <24> above, which is a pants-type disposable diaper.

[Examples]

Hereinafter, the present invention will be described in detail by way of examples. However, the scope of the present work is not limited by this embodiment. Unless otherwise stated, "%" means "% by mass".

[Example 1]

An M-size disposable diaper for infants of the form shown in Fig. 1 was produced. The top sheet in the diaper includes a non-woven fabric of the form shown in Fig. 2, and the nonwoven fabric is produced by the same method as that described in the first embodiment of JP-A-2012-136792. The basis weight of the nonwoven fabric was 30 g/m ² , and the protruding portions on one side were arranged in a zigzag lattice shape. The distance between the protrusions is 5 mm. The same is true on the other side. The thickness of the nonwoven fabric was 2.1 mm at a load of 0.05 kPa. As the back sheet in the diaper, a liquid-impermeable polyethylene film is used. As a leak-proof cuff, a water-repellent spunbond-meltblown-spun non-woven fabric is used. The absorbent core in the absorbent body comprises fluff pulp and a superabsorbent polymer. The basis weight of the fluff pulp contained in the entire absorbent core was 172 g/m ² , and the basis weight of the superabsorbent polymer was 257 g/m ² . In the method of making the ratio of the presence of the fluff pulp and the superabsorbent polymer to the skin contact surface side and the non-skin contact surface side in the absorbent core, the method described in Japanese Laid-Open Patent Publication No. 2007-37668 is used. method. As a result, in the absorbent core, the ratio of the presence of the superabsorbent polymer gradually decreases from the skin contact surface side to the non-skin contact surface side, and the ratio of the fluff pulp is from the non-skin contact surface side to the skin. The junction side is gradually reduced. The ratio of the presence of the superabsorbent polymer in the skin abutting surface and the vicinity thereof was 69.3%. On the other hand, the ratio of the presence of the fluff pulp in the non-skin abutting surface and the vicinity thereof was 63.8%. The superabsorbent polymer used was the polymer A shown in Table 1. Regarding the polymer A, the absorption rate was 65 seconds, and the centrifugal retention amount according to JIS K 7223 was 31.5 g/g, and the liquid permeation rate under pressure was 70 ml/min. As the packaged core material covering the absorbent core, a natural pulp NBKP having a basis weight of 18 g/m ² was used. The skin abutting surface of the absorbent core and the packaged core material are joined by a hot melt adhesive. The hot-melt adhesive was applied by using a summit spray, as shown in Fig. 4, in a spiral pattern formed by two rows. The thickness of the spiral was 0.05 to 0.2 mm, and the width W of the coated region composed of a spiral formed by two rows as shown in Fig. 4 was 5.5 mm. Five peak-shaped coated regions of this width are formed. The distance between the adjacent peak-shaped coated regions was 12 mm. The total coating amount of the hot melt adhesive was 3 g/m ² .

[Embodiment 2]

In Example 1, the basis weight of the pulp in the absorbent core and the basis weight of the superabsorbent polymer were as shown in Table 1. Further, as the superabsorbent polymer, the polymer B shown in Table 1 was used. Regarding the polymer B, the absorption rate was 44 seconds, and the centrifugal retention amount according to JIS K 7223 was 32.8 g/g, and the liquid permeation rate under pressure was 21 ml/min. A disposable diaper was produced in the same manner as in Example 1 except for the above.

[Example 3]

In Example 1, the basis weight of the pulp in the absorbent core and the basis weight of the superabsorbent polymer were as shown in Table 1. A disposable diaper was produced in the same manner as in Example 1 except for the above.

[Comparative Example 1]

In the comparative example, the coating pattern of the hot-melt adhesive applied between the skin contact surface and the packaged core material applied to the absorbent core was changed in Example 1. Further, the front and back of the absorbent core used in Example 1 were reversed. The coating pattern of the hot-melt adhesive in this comparative example was set as a coater strip. The thickness of the coater was 2.5 mm, and the distance between adjacent coaters was 2.5 mm. Further, the total amount of the hot-melt adhesive applied was 3 g/m ² . A disposable diaper was obtained in the same manner as in Example 1 except for the above.

[Comparative Example 2]

In the comparative example, a flat non-woven fabric was used instead of the front surface sheet having the uneven shape used in Example 1 as a front sheet. The flat non-woven fabric comprises a composite fiber of polyethylene terephthalate (PET) and polyethylene (PE) of 2.0 dtex, and a composite fiber of polypropylene (PP) and polyethylene (PE) of 5.6 dtex. The layer structure has a hot air non-woven fabric with a basis weight of 25 g/m ² . A disposable diaper was obtained in the same manner as in Example 1 except for the above.

[Comparative Example 3]

In this comparative example, a polymer C which is a superabsorbent polymer having a relatively high absorption speed and a relatively small centrifugal retention amount was used instead of the polymer B as a superabsorbent polymer used in Example 2. Regarding the polymer C, the absorption rate was 3 seconds, and the centrifugal retention amount according to JIS K 7223 was 23.4 g/g, and the liquid permeation rate under pressure was 0 ml/min. A disposable diaper was obtained in the same manner as in Example 2 except for the above.

[Comparative Example 4]

In this comparative example, a polymer D as a superabsorbent polymer having a relatively fast absorption speed and a relatively small centrifugal retention amount was used instead of the polymer A as a superabsorbent polymer used in Example 1. With respect to the polymer D, the absorption rate was 29 seconds, the centrifugal retention amount according to JIS K 7223 was 25.3 g/g, and the liquid permeation rate under pressure was 130 ml/min. Further, the basis weight of the fluff pulp contained in the entire absorbent core was 191 g/m ² , and the basis weight of the superabsorbent polymer was 300 g/m ² . A disposable diaper was obtained in the same manner as in Example 1 except for the above.

[Comparative Example 5]

This comparative example uses another absorbent core instead of the absorbent core used in Example 1. The basis weight of the fluff pulp contained in the whole of the absorbent core used in the comparative example was 200 g/m ² , and the basis weight of the superabsorbent polymer was 186 g/m ² . The presence of the fluff pulp and the superabsorbent polymer in the absorbent core was substantially equal, and the ratio of the presence of the superabsorbent polymer in the skin abutting surface and the vicinity thereof was 48.5%. On the other hand, the ratio of the presence of the fluff pulp in the non-skin contact surface and the vicinity thereof was 52.1%. A disposable diaper was obtained in the same manner as in Example 1 except for the above.

[assessment]

With respect to the diapers obtained in the examples and the comparative examples, the degree of diffusion of the liquid in the surface direction of the skin contact surface side and the non-skin contact surface side of the absorbent body was measured by the above method. The results are shown in Table 1 below.

As is clear from the results shown in Table 1, the diaper (this creation) of each example has a smaller liquid diffusion area on the skin contact surface side than the diaper of each comparative example. Further, it is also known that the diaper of each of the examples has a smaller ratio of the liquid diffusion area on the skin contact surface side to the liquid diffusion area on the non-skin contact surface side than the diaper of each comparative example.

[Industrial availability]

According to the absorbent article of the present invention, the diffusion of the liquid on the contact surface side of the skin can be suppressed, and the liquid can be largely diffused on the non-skin contact surface side. Therefore, according to the absorbent article of the present invention, the liquid to the skin can be reduced or returned, and the humidity in the space between the absorbent article and the skin can be lowered. Further, it is possible to efficiently dissipate heat or water vapor to the outer boundary of the non-skin contact surface.

10‧‧‧Disposable diapers

11‧‧‧Front sheet

11a‧‧‧1st protrusion

11b‧‧‧2nd protrusion

11c‧‧‧ Space

11d‧‧‧ space

12‧‧‧Back sheet

13‧‧‧Acceptor

16‧‧‧Absorbing core

17‧‧‧Package

20‧‧‧Binder

Z‧‧‧ Thickness direction

Claims (27)

An absorbent article comprising a front sheet located on a side of the skin of the wearer, a back sheet located on a side away from the skin of the wearer, and an absorbent body between the front sheet and the back sheet And an absorbent article having a longitudinal direction and a longitudinal direction orthogonal thereto; wherein the absorbent body comprises an absorbent core and a coated core material covering the absorbent core; the absorbent core system mixes pulp fibers and is highly absorbent The superabsorbent polymer has an absorption rate of 30 seconds or more and 150 seconds or less, and the absorbent core includes a first surface having a high ratio of the superabsorbent polymer and the first surface. On the opposite side, the second surface having a higher ratio of the pulp fibers; the absorbent core system is disposed such that the first surface thereof is located on the skin contact surface side and the second surface is located on the non-skin contact surface side; At least a concave-convex structure is formed on the opposing surface side of the absorber, and a space due to the uneven structure is formed between the front sheet and the absorber; and in the absorber, the absorbent core is 1 side A plurality of said clad core-sheet strip extending in the longitudinal direction and then intermittently bonded area in the width direction. The absorbent article according to claim 1, wherein the mass ratio of the above-mentioned superabsorbent polymer/the above-mentioned pulp fiber in the absorbent core is 1 or more and 2 or less. The absorbent article according to claim 1 or 2, wherein the above-mentioned superabsorbent polymer in the absorbent core has a basis weight of 30 g/m ² or more and 350 g/m ² or less, and the basis weight of the above pulp fiber is 30 g/m. ² or more and 300 g/m ² or less. The absorbent article according to claim 1 or 2, wherein, in the above-mentioned superabsorbent polymer, the centrifugal retention amount according to JIS K 7223 is 25 g/g or more and 65 g/g or less, and the liquid permeation rate under pressure is 20 ml/ Above min and below 1000ml/min. The absorbent article according to claim 1 or 2, wherein the ratio of the area of the first surface of the absorbent core to the area of the succeeding region of the packaged core material and the area of the non-adjacent area is [the area of the subsequent area/area of the non-adjacent area ] is expressed as 0.5 or more and 1.2 or less, and the width of the non-adjacent region is 8 mm or more. The absorbent article of claim 5, wherein the non-adjacent area has a width of 30 mm or less. The absorbent article according to claim 1 or 2, wherein the ratio of the liquid diffusion area on the skin contact surface side of the absorbent body to the liquid diffusion area on the non-skin contact surface side is [the liquid diffusion area on the skin contact surface side/ The liquid diffusion area on the non-skin contact surface side is expressed by 0.5 or more and 0.8 or less. The absorbent article of claim 1 or 2, wherein the front sheet and the absorbent body are discontinuously spaced apart in the plane direction by the space. The absorbent article according to claim 1 or 2, wherein the front sheet comprises a first surface that abuts against the skin of the wearer and a second surface that faces the absorbent body; and the first surface has a plurality of first projections The portions are extended in the in-plane oblique relationship in two directions of the vertical and horizontal directions, and any of the first directions in the plane and the second direction oblique thereto intersect at an angle of 30° or more and 90° or less. The absorbent article according to claim 1 or 2, wherein the front sheet comprises a first surface that abuts against the skin of the wearer and a second surface that faces the absorbent body; and a plurality of the first surface side a protruding portion; a plurality of second protruding portions are arranged on the second surface side; the first protruding portion and the second protruding portion protrude in opposite directions with respect to the sheet surface of the front sheet; and the two protruding portions are formed to They are alternately arranged in a non-overlapping relationship regardless of whether they are in the same position in a plan view or in a side view. The absorbent article of claim 10, wherein the first protruding portion and the second protruding portion are arranged In the form of the first protruding portion, six second protruding portions are arranged at the apex of the hexagonal shape, and the pattern is expanded in the plane. The absorbent article according to claim 10, wherein the protruding shape of the first protruding portion is hemispherical, and the protruding shape of the second protruding portion is sharp and the top has a curved conical or truncated cone shape. The absorbent article according to claim 10, wherein the position of the apex of the first protruding portion to the position of the apex of the second protruding portion is 1 mm or more and 4.5 mm or less. The absorbent article of claim 1 or 2, wherein the coated core material covers the entire surface of the facing sheet of the absorbent core and covers the entire surface of the back sheet of the absorbent core. The absorbent article of claim 1 or 2, wherein the ratio of the presence of the superabsorbent polymer in the absorbent core is between the skin abutting surface and the non-skin abutting surface in the thickness direction of the absorbent core, The skin abutting surface is gradually reduced gradually or non-continuously in a stepwise manner. The absorbent article according to claim 1 or 2, wherein the ratio of the presence of the pulp fibers in the absorbent core is between the skin abutting surface and the non-skin abutting surface in the thickness direction of the absorbent core, from the non-skin The contact surface for the skin is continuously reduced gradually or discontinuously in a stepwise manner. The absorbent article according to claim 1 or 2, wherein the ratio of the superabsorbent polymer is 60% by mass or more and 95% by mass or less at the skin contact surface of the absorbent core and the vicinity thereof, and the ratio of the pulp fibers is 5 mass% or more and 40 mass% or less. The absorbent article according to claim 1 or 2, wherein the amount of the superabsorbent polymer in the absorbent core is 50 g/m ² or more and 300 g/m ² or less, and the amount of the pulp fiber is 50 g/m ² or more and 250 g/ Below m ² . The absorbent article of claim 1 or 2, wherein the coated core material comprises a liquid permeable fibrous sheet comprising a tissue or a non-woven fabric, The woven fabric comprises a spunbond nonwoven fabric, a spunbond-meltblown-spunbond (SMS) nonwoven fabric, a hot air non-woven fabric or a water needle non-woven fabric. The absorbent article according to claim 1 or 2, wherein the adhesive agent is applied in a spiral, striped or Ω-shaped coating pattern to form the above-mentioned succeeding region. The absorbent article according to claim 1 or 2, which has a longitudinal direction Y and a width direction X orthogonal thereto, and has a shape elongated in the longitudinal direction Y, and a central portion of the longitudinal direction Y is a lower portion of the crotch. The front and rear sides are the ventral side and the back side. The absorbent article of claim 21, wherein the left and right sides in the width direction X have one pair of leakage preventing flanges extending in the longitudinal direction Y; and the leakage preventing flange extends over the entire length of the absorbent article; The flange comprises a pair of sheets which are longer in the length direction Y and which are folded in the longitudinal direction Y; the leakage preventing flange has a free end and a fixed end along the length direction Y, and the free end is along the opposite sheet In the portion of the fold line, the elastic member is disposed and fixed to the free end in an extended state. The absorbent article of claim 22, wherein the left and right sides form a leg cuff; and the leg is cuffed, and the elastic member is disposed in an extended state at a portion where the fixed end of the leakage preventing cuff is joined to the back sheet. Fixed between the two. An absorbent article according to claim 1 or 2 which is a disposable diaper. An absorbent article according to claim 24, which is a detachable disposable disposable diaper. The absorbent article according to claim 25, wherein a pair of fastening tapes are provided on the left and right side edges of the back side portion, and a fixing tape for fixing the fastening tape is provided on the outer surface of the abdominal side portion. An absorbent article according to claim 24, which is a pull-on disposable diaper.