Absorbent articles

Abstract

To provide an absorber which reduces unintended deformation and twisting when worn and is excellent in followability to movements of a wearer's body, and an absorbent article provided with the same.SOLUTION: An absorber 4 in an absorbent article 1 includes a fiber lump 11 containing synthetic fiber and a water absorptive fiber 12. The absorber 4 has a pair of recessed parts 7 which recess from a skin facing surface to a non-skin facing surface and extend in a vertical direction. When the absorber 4 is divided into a horizontal central area 4C positioned more inward in a horizontal direction than each recessed part 7 and a pair of lateral side areas 4S positioned more outward in the horizontal direction than the respective recessed parts 7, a high basis weight area 45 in which a proportion of basis weight of the fiber lump 11 against basis weight of the water absorptive fiber 12 is higher than the proportion of the horizontal central area 4C is formed in each lateral side area 4S. The high basis weight area 45 is positioned so as to go along a side edge along a vertical direction X of the absorber 4 at least in the vertical central area M.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to an absorbent article. [Background technology]

[0002] Absorbent articles such as sanitary napkins generally include an absorbent body. The absorbent body typically includes an absorbent core containing absorbent materials such as absorbent fibers such as wood pulp and absorbent polymers, and further includes a core wrap sheet that covers the outer surface of the absorbent core.

[0003] The present applicant has proposed an absorbent body containing synthetic fiber-containing fiber agglomerates and an absorbent article equipped with the same, with the aim of improving the wearing comfort, cushioning properties, compression recovery, etc. (Patent Documents 1 and 2). These absorbent bodies are configured such that the fiber agglomerates are uniformly present within the absorbent body, or the mass ratio of the fiber agglomerates is smaller on the skin-facing side of the absorbent body than on the non-skin-facing side.

[0004] Patent Document 3 describes an absorbent body in which a nonwoven fabric piece having a three-dimensional structure in which heat-fusible fibers are bonded to each other and hydrophilic fibers are mixed together. Patent document 4 describes an absorbent article in which the absorbent body interposed between the top sheet and the back sheet is composed of a cushion layer located on the top sheet side and made up of an assembly of strips of nonwoven fabric, and an absorbent layer located on the back sheet side. Patent Document 5 describes an absorbent body for absorbent articles, which is formed by mixing pieces of nonwoven fabric containing heat-sealable fibers and having a three-dimensional structure formed by previously bonding the fibers together with hydrophilic fibers. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2019-063469 A [Patent Document 2] JP 2019-098157 A [Patent Document 3] JP 2002-301105 A [Patent Document 4] JP 2003-052750 A [Patent Document 5] JP 2011-244894 A Summary of the Invention [Problem to be solved by the invention]

[0006] Since absorbent articles are generally used by being sandwiched between the thighs of a wearer, the absorbent article is easily subjected to external forces inward in the width direction. This causes the absorbent article to undergo unintended deformation or twisting when worn, which in turn contributes to leakage of excreted bodily fluids. The techniques described in Patent Documents 1 to 5 have room for improvement in terms of further reducing deformation and twisting and further improving the ability to follow the movement of the wearer's body.

[0007] Therefore, an object of the present invention is to provide an absorbent body that reduces unintended deformation and twisting when worn and has excellent conformability to the movement of the wearer's body, and an absorbent article including the absorbent body. [Means for solving the problem]

[0008] The present invention provides an absorbent article having a vertical direction corresponding to the front-to-rear direction of a wearer and a horizontal direction perpendicular thereto, the article having a vertical central region arranged to face an excretory portion of the wearer, a front region arranged vertically forward of the vertical central region, and a rear region arranged vertically rearward of the vertical central region, the article comprising an absorbent body, The absorbent body includes a fiber mass including synthetic fibers and a water-absorbent fiber, The absorbent body has a pair of recesses extending in the longitudinal direction from the skin-facing surface toward the non-skin-facing surface, When the absorbent body is divided into a lateral central region located laterally inward from each of the recesses and a pair of lateral side regions located laterally outward from each of the recesses, A high basis weight region is formed in each of the lateral side regions, in which the ratio of the basis weight of the fiber mass to the basis weight of the water-absorbent fiber is higher than the ratio in the lateral central region, The present invention provides an absorbent article in which the high basis weight region is located at least in the longitudinal central region so as to include side edges of the absorbent body along the longitudinal direction. Effect of the Invention

[0009] According to the present invention, there is provided an absorbent body that is excellent in conformity with the movement of the wearer's body by reducing unintended deformation and twisting when worn, and an absorbent article including the same. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a partially cutaway plan view showing a schematic view of the skin-facing side of a sanitary napkin, which is one embodiment of the absorbent article of the present invention. [Diagram 2] FIG. 2 is a cross-sectional view showing a schematic cross section of one embodiment taken along line II in FIG. [Diagram 3] FIG. 3 is a cross-sectional view showing a schematic cross section of another embodiment taken along line II in FIG. [Figure 4] FIG. 4 is a cross-sectional view showing a schematic cross section of still another embodiment taken along the line II in FIG. [Diagram 5] FIG. 5 is a cross-sectional view showing a schematic cross section of still another embodiment taken along the line II in FIG. [Figure 6] FIG. 6 is a cross-sectional view showing a schematic cross section of still another embodiment taken along the line II in FIG. [Figure 7] FIG. 7 is a schematic plan view showing one embodiment of an absorbent body. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] The present invention will be described below based on preferred embodiments with reference to the drawings. Figures 1 and 2 show a sanitary napkin (hereinafter, simply referred to as a napkin) 1, which is one embodiment of the absorbent article of the present invention. The napkin 1 is an article used to absorb bodily fluids such as menstrual blood excreted from the wearer.

[0012] 1, the napkin 1 has a vertical direction X that corresponds to the front-to-rear direction of the wearer and extends from the wearer's abdomen through the crotch area to the back, and a horizontal direction Y perpendicular to the vertical direction X. In the vertical direction X, the napkin 1 has a vertical central region M including an excretory part facing portion (excretion point) that faces an excretory part such as the vaginal opening of the wearer, a front region F that is disposed in front of the wearer (ventral side) of the vertical central region M, and a rear region R that is disposed behind the wearer (dorsal side) of the wearer.

[0013] The napkin 1 comprises an absorbent body 4 for absorbing and retaining excreted bodily fluids. In addition, the napkin 1 preferably further comprises a liquid-permeable top sheet 2 that can come into contact with the wearer's skin, and a leak-proof back sheet 3. In this case, the absorbent body 4 is disposed between the top sheet 2 and the back sheet 3.

[0014] In this specification, the "skin-facing side" refers to the side of the absorbent article or its constituent member (e.g., absorbent body 4) that faces the wearer's skin when the absorbent article is worn, i.e., the side relatively closer to the wearer's skin, and the "non-skin-facing side" refers to the side of the absorbent article or its constituent member that faces the opposite side to the skin when the absorbent article is worn, i.e., the side relatively farther from the wearer's skin. Note that "when worn" here refers to the normal, proper wearing position, i.e., a state in which the absorbent article is maintained in the correct wearing position.

[0015] 1 and 2, the napkin 1 may further have a pair of wing portions 5W, 5W extending outward in the horizontal direction Y from both side portions along the vertical direction X of the vertical central region M. In this embodiment, the pair of wing portions 5W, 5W are formed symmetrically with respect to a vertical center line that divides the napkin 1 in the horizontal direction Y and extends in the vertical direction X.

[0016] When the absorbent article has wing portions 5W like the napkin 1, the vertical central region in the absorbent article of the present invention corresponds to the region having the wing portions in the vertical direction X of the absorbent article. Specifically, as shown in Fig. 1, it is the region sandwiched between the base of one wing portion 5W of the napkin 1 along the vertical direction X and the base of the other wing portion 5W along the vertical direction X. Moreover, the vertical central region in an absorbent article (for example, a disposable diaper) that does not have wing portions corresponds to a region located in the middle when the absorbent article is divided into three equal parts in the vertical direction.

[0017] The absorbent body 4 is configured to include an absorbent core 40 that absorbs and retains bodily fluids such as menstrual blood, and a liquid-permeable core wrap sheet 41 that covers the outer surface of the absorbent core 40 . In this embodiment, the absorbent core 40 has a shape that is elongated in the vertical direction X when viewed in a plane, and the longitudinal direction of the absorbent core 40 coincides with the vertical direction X of the napkin 1, and the width direction of the absorbent core 40 coincides with the horizontal direction Y of the napkin 1. 1, the absorbent body 4 extends over substantially the entire length of the napkin 1 in the longitudinal direction X, from the front region F through the longitudinal central region M to the rear region R. The absorbent core 40 and the core wrap sheet 41 may be joined together with an adhesive such as a hot melt adhesive.

[0018] The core wrap sheet 41 may be composed of only one sheet, or may be composed of multiple sheets. The core wrap sheet 41 in the former form is a single continuous sheet, which covers the entire skin-facing surface of the absorbent core 40, and extends outward in the horizontal direction Y from both side edges of the absorbent core 40 along the vertical direction X, and the extended portions are rolled down below the absorbent core 40 to cover the entire non-skin-facing surface of the absorbent core 40. The core wrap sheet 41 in the latter form is composed of two sheets, for example, one skin-side core wrap sheet that covers the skin-facing surface of the absorbent core 40, and one non-skin-side core wrap sheet that is separate from the skin-side core wrap sheet and covers the non-skin-facing surface of the absorbent core 40. In either form, the core wrap sheet 41 is composed of paper or a water-permeable nonwoven fabric.

[0019] As shown in Figs. 1 and 2, when the napkin 1 further comprises a top sheet 2 and a back sheet 3, the top sheet 2 is arranged so as to cover the entire skin-facing surface of the absorbent body 4. The back sheet 3 covers the entire non-skin-facing surface of the absorbent body 4, and further extends outward in the lateral direction Y from both side edges of the absorbent body 4 along the longitudinal direction X to form side flap portions together with side sheets 6 described below. The side flap portions are portions of the napkin 1 made of members extending outward in the lateral direction Y from the absorbent body 4. The back sheet 3 and the side sheets 6 are joined to each other at the extending portions from both side edges of the absorbent body 4 along the longitudinal direction X by a known joining method such as adhesive, heat sealing, ultrasonic sealing, etc. The top sheet 2 and the back sheet 3 may be joined to the absorbent body 4 by an adhesive.

[0020] The napkin 1 preferably has a pair of side sheets 6, 6 on both sides along the longitudinal direction X of the skin-facing surface of the topsheet 2. The side sheets 6 are arranged over substantially the entire length in the longitudinal direction X so as to overlap with both left and right sides along the longitudinal direction X of the absorbent body 4 in a plan view. As shown in FIG. 2, the side sheet 6 has a free end that is not joined to other components such as the top sheet 2, and a fixed end that is a joint joined to another component. When in use, the fixed end and the free end are spaced away from the top sheet 2 to form a leak-proof pocket that prevents lateral leakage.

[0021] As shown in Fig. 1, the side flap portion protrudes outward in the horizontal direction Y in the vertical central region M, thereby providing a pair of wing portions 5W, 5W extending outward in the horizontal direction Y. In the plan view shown in Fig. 1, the wing portion 5W has a substantially trapezoidal shape with its lower base (a side longer than its upper base) located on the inner side in the horizontal direction Y.

[0022] As the top sheet 2 and the back sheet 3, various types of sheets conventionally used in absorbent articles can be used without any particular limitation. For example, a liquid-permeable single-layer or multi-layer nonwoven fabric can be used as the top sheet 2. Examples of such nonwoven fabric include nonwoven fabrics produced by a carding method (e.g., air-through nonwoven fabrics), spunbond nonwoven fabrics, meltblown nonwoven fabrics, spunlace nonwoven fabrics, and needle-punched nonwoven fabrics. The nonwoven fabric constituting the top sheet 2 may be subjected to a hydrophilization treatment using a hydrophilizing agent such as a surfactant. As the back sheet 3, a leakproof sheet can be used, that is, a sheet that is liquid-impermeable (the property of not allowing liquid to pass through at all) or liquid-difficult to pass through (although not liquid-impermeable, the property of allowing liquid to pass through with difficulty), for example, a moisture-permeable resin film can be used. The side sheet 6 is preferably a liquid-impermeable sheet, and for example, the same sheet that can be used as the back sheet 3 can be used.

[0023] Furthermore, it is preferable that an adhesive section 9 for fixing the napkin 1 to clothing such as shorts is provided on the non-skin facing surface of the backsheet 3 of the napkin 1. The positional relationship between the absorbent body 4 and the adhesive section 9 will be described later.

[0024] Furthermore, wing portion 5W may be provided with a wing portion adhesive portion (not shown) on its non-skin facing surface as a fastening means for fastening wing portion 5W to clothing such as shorts. Generally, wing portion 5W is used by being folded back onto the non-skin facing surface (outer surface) of clothing such as shorts, and therefore the non-skin facing surface of wing portion 5W, on which the wing portion adhesive portion is formed, faces the wearer's skin during use and becomes the skin facing surface. Before the napkin 1 is used, the wing adhesive parts and adhesive part 9 are each covered with a release sheet (not shown) made of film, nonwoven fabric, paper or the like.

[0025] Returning to the explanation of the absorbent body 4, the absorbent core 40 in the absorbent body 4 is composed of fiber agglomerates 11 containing synthetic fibers and water-absorbent fibers 12, as shown in Fig. 2. From the viewpoint of improving liquid absorption and liquid retention, the absorbent core 40 preferably further contains a plurality of particulate water-absorbent polymers in addition to the fiber agglomerates 11 and the water-absorbent fibers 12 (not shown).

[0026] In the absorbent core 40, it is preferable that the fiber agglomerates 11 and the absorbent fibers 12 are not simply mixed together, but that the fiber agglomerates 11 or the fiber agglomerates 11 and the absorbent fibers 12 are intertwined with each other. With such a configuration, the absorbent core 40 has high shape retention. In addition, the absorbent body 4 including the absorbent core 40 has excellent conformability and deformability to external forces received from various directions when worn, while also having excellent flexibility, cushioning properties, and compression recovery. An absorbent article including this absorbent body 4 easily deforms and recovers from external forces, and is therefore less likely to twist, allowing the napkin 1 to have a high fit to the wearer's body.

[0027] In this specification, entanglement includes both (i) a form in which the fiber agglomerates 11 or absorbent fibers 12 to be entangled are not fused to each other, but are maintained in a bonded state by the entanglement of the constituent fibers of the fiber agglomerates 11, and (ii) a form in which the fiber agglomerates 11 are not bonded to each other in the natural state of the absorbent core 40 (a state in which no external force is applied), but the fiber agglomerates 11 can be bonded to each other by the entanglement of the constituent fibers when an external force is applied to the absorbent core 40. Here, "a state in which an external force is applied to the absorbent core 40" means, for example, a state in which a deforming force is applied to the absorbent core 40 while an absorbent article to which the absorbent core 40 is applied is being worn.

[0028] The fiber agglomerates 11 are fiber aggregates in which a plurality of synthetic fibers are accumulated and integrated into a clump shape, and a plurality of fiber agglomerates 11 are present in the absorbent core 40 while retaining their shape. The fiber agglomerates 11 mainly contribute to improving the flexibility, cushioning properties, compression recovery, and shape retention of the absorbent core 40 due to the shape of the fiber aggregates.

[0029] In this specification, the term "fiber aggregate" refers to a fiber aggregate in which a plurality of fibers are integrated together, and is configured separately from the water-absorbent fiber 12. The fiber aggregate used in the present invention is, for example, a fiber aggregate of a fixed shape such as a sheet piece obtained by cutting a synthetic fiber sheet to a certain dimension. As such a fiber aggregate, for example, the fiber aggregates described in JP 2019-063469 A, JP 2019-098157 A, and JP 2020-188918 A can be suitably used.

[0030] The resin constituting the synthetic fiber is preferably a thermoplastic resin. Examples of the thermoplastic resin include polyolefins such as polyethylene and polypropylene, polyesters such as polyethylene terephthalate, polyamides such as nylon 6 and nylon 66, polyacrylic acid, polymethacrylic acid alkyl esters, polyvinyl chloride, polyvinylidene chloride, etc., and these may be used alone or in combination of two or more.

[0031] A plurality of absorbent fibers 12 are present in the absorbent core 40, and although the plurality of absorbent fibers 12 may be entangled with one another, it is preferable that the absorbent fibers 12 are not accumulated like the synthetic fibers that are the constituent fibers of the fiber mass 11, but exist independently. The absorbent fibers 12 mainly contribute to improving the liquid absorbency of the absorbent core 40, and also contribute to improving the shape retention of the absorbent core 40.

[0032] The absorbent fiber 12 may be any absorbent fiber conventionally used as a material for forming the absorbent body of this type of absorbent article, and examples of such fibers include natural fibers such as wood pulp, such as softwood pulp or hardwood pulp, non-wood pulp, such as cotton pulp or hemp pulp, modified pulp, such as cationic pulp or mercerized pulp, and regenerated cellulose fibers, such as rayon, and may be used alone or in combination of two or more. Considering that the main role of the absorbent fiber 12 is to improve the liquid absorbency of the absorbent body 4, cellulosic fibers are particularly preferred as the absorbent fiber 12.

[0033] As shown in Figures 1 and 2, the napkin 1 has a pair of recesses 7 in which the absorbent body 4 is recessed from its skin-facing surface toward its non-skin-facing surface. Each of the pair of recesses 7, 7 is formed at least in the vertical central region M, and is formed to extend in the vertical direction X. The recesses 7 are formed by integrally recessing the core wrap sheet 41 and the absorbent core 40. The recesses 7 do not penetrate the absorbent body 4, but have an opening on the skin-facing surface and a bottom on the opposite side to the opening. The recesses 7 formed on the skin-facing surface of the napkin 1 have the function of inhibiting the movement of bodily fluids, such as menstrual blood, in the planar direction.

[0034] 1 and 2, when the topsheet 2 is further provided, the recessed portion 7 is preferably formed by integrally recessing the topsheet 2, and the core wrap sheet 41 and absorbent core 40 as the absorbent body 4. With such a configuration, the fit when worn is further improved.

[0035] The recess 7 in this embodiment is configured to include a pair of left and right vertical recesses 7X, 7X extending in the vertical direction X, and a pair of front and rear horizontal recesses 7Y, 7Y extending in the horizontal direction Y. Each of the recesses 7X, 7Y in this embodiment is formed by integrally depressing the topsheet 2 and the absorbent body 4. The pair of vertical recesses 7X, 7X each extend in a straight or curved shape across the entire area of ​​the vertical central area M in the vertical direction X, and further extend into the front area F and rear area R, forming a continuous line overall. One of the pair of lateral recesses 7Y, 7Y is at least partially located in the front region F, and the other is at least partially located in the rear region R. The pair of lateral recesses 7Y, 7Y form a continuous line that is U-shaped or arc-shaped convex outward in the vertical direction X in a plan view, and the apex of the U-shape or arc-shape is located in the central region of the napkin 1 in the horizontal direction Y.

[0036] The recesses 7X, 7Y constituting the recess 7 are connected to each other at their longitudinal ends, and the recess 7 as a whole has an elongated elliptical shape in a plan view. In the vertical central region M, the area surrounded by the pair of vertical recesses 7X, 7X is located in the center of the vertical central region M and includes the excretion portion facing portion (excretion point). The recess 7 shown in the figure is formed line-symmetrically with respect to the vertical center line described above, but does not have to be line-symmetrical as long as the effects of the present invention are achieved.

[0037] The above-mentioned recessed portion 7 can be suitably formed by applying a compression process from the skin-side core wrap sheet side, which is the skin-facing side of the napkin 1, or from the topsheet 2 side. In this case, the recessed portion 7 is synonymous with a so-called compressed portion. The recessed portion 7 thus formed is a portion in the thickness direction Z where the density of the constituent material is higher than that of the surrounding area of ​​the recessed portion 7 in the absorbent body 4. As such a compression process, for example, a known embossing process such as embossing with or without the application of heat, ultrasonic embossing, etc. can be used.

[0038] For ease of explanation, the embodiment of napkin 1 shown in Figure 2 has been described as having recessed portion 7 in which absorbent body 4 is recessed from its skin-facing surface toward its non-skin-facing surface; however, in addition to this, or instead, absorbent body 4 may have a back surface recessed portion in which absorbent body 4 is recessed from its non-skin-facing surface toward its skin-facing surface (not shown).

[0039] When a back surface recess is formed, the back surface recess is formed by integrally recessing the core wrap sheet 41 and the absorbent core 40 in the absorbent body 4, similar to the shape of the recess 7 described above. The back surface recess has approximately the same shape and dimensions as the recess 7 in a plan view, and is preferably formed at a position overlapping the recess 7 in a plan view in terms of improving fit. The back surface recess can be suitably formed by applying a compression process from the non-skin side core wrap sheet side in the same manner as the recess 7. Where no particular explanation is given about the back surface recess, the explanation about the recess 7 described above applies as appropriate.

[0040] One of the features of the absorbent body 4, which is a constituent member of the napkin 1, is that the positions at which the recesses 7 are formed and the proportions of the fiber agglomerates 11 and the water-absorbent fibers 12 present therein have a predetermined relationship.

[0041] In detail, as shown in FIG. 2, the region located inward in the horizontal direction Y from each of the vertical recesses 7X, 7X, which are a pair of recesses 7 formed in the absorbent body 4, is defined as a horizontal central region 4C, and a pair of regions located outward in the horizontal direction Y from each of the vertical recesses 7X, 7X are defined as horizontal lateral regions 4S, 4S. When each region is divided in this manner, it is preferable that a high basis weight region 45, which is a region in which the ratio of the basis weight W1 of the fiber agglomerates 11 to the basis weight W2 of the absorbent fiber 12 (hereinafter also referred to as the "W1 / W2 ratio") is higher than the W1 / W2 ratio in the lateral central region 4C, is formed in each of the lateral side regions 4S, 4S. In addition, it is preferable that each high basis weight region 45, 45 is located at least in the longitudinal central region M so as to include the side edge 4a along the longitudinal direction X of the absorbent body 4. In other words, it is preferable that the absorbent body 4 in the napkin 1 has a portion in which the fiber agglomerates 11 are relatively more abundant than other portions, which is unevenly distributed in the outer region in the lateral direction Y of the absorbent body 4. The high basis weight region 45 is approximately uniform in the thickness direction Z of the absorbent body 4. A pair of high basis weight regions 45 may exist only in the longitudinal central region M, or may extend in the longitudinal direction X so as to include the longitudinal central region M of the absorbent body 4 and also include the front region F and the rear region R. In either case, it is preferable that the width (length along the lateral direction Y) of the high basis weight region 45 is constant in order to reduce unintended deformation and twisting.

[0042] By forming the high basis weight regions 45 in the lateral outer regions of the absorbent body 4, the flexibility and cushioning of the absorbent body 4 is sufficiently maintained while the ability to follow the external force inward in the lateral direction Y generated by the napkin 1 being pinched between both thighs when worn can be increased, improving the fit when worn. Furthermore, when the above-mentioned external force is released or weakened, the compression recovery and shape retention of the absorbent body 4 caused by the presence of the fiber agglomerations 11 can be easily improved in the lateral direction Y, and unintended deformation and twisting of the napkin 1 when worn can be reduced. The absorbent core 40 having a different ratio of the fiber agglomerates 11 and the water-absorbent fibers 12 can be manufactured, for example, by appropriately adjusting the fiber stacking order on a rotating drum in a known fiber stacking device.

[0043] In this specification, the boundary L between the lateral central region 4C and the lateral side regions 4S is based on the position of the outer end of the vertical recess 7X in the lateral direction Y (see FIG. 2). When the vertical recess 7X is formed only in the vertical central region M of the napkin 1, the lateral central region 4C and the lateral side regions 4S in the front region F and the rear region R are regions that are distinguished when the vertical recess 7X is virtually extended in the longitudinal direction X.

[0044] The high basis weight region 45 may be formed so that its inner end in the lateral direction Y coincides with the outer end in the lateral direction Y of the vertical recess 7X, or the inner end in the lateral direction Y of the high basis weight region 45 may be located laterally outward and spaced from the outer end in the lateral direction Y of the vertical recess 7X. In the latter case, the region in the absorbent core 40 from the inner end in the lateral direction Y of the high basis weight region 45 to the recess 7 may have the same configuration as the absorbent core 40 in the lateral central region 4C, and the above-mentioned W1 / W2 ratio may decrease continuously or stepwise when viewed inward in the lateral direction Y from the high basis weight region 45 to the lateral central region 4C. Furthermore, in the absorbent core 40 at the position overlapping with the recess 7 in a plan view, it is sufficient that at least absorbent fibers 12 are present, and in addition to this, fiber agglomerates 11 may be present or may not be present.

[0045] The W1 / W2 ratios in the high basis weight regions 45 are each independently preferably 1.0 or more, more preferably 1.5 or more, and preferably 4.0 or less, more preferably 3.0 or less. By having the high basis weight regions 45 have such a W1 / W2 ratio, it is possible to improve recovery during liquid absorption without causing discomfort when worn, such as stiffness. The W1 / W2 ratios in each high basis weight region 45 may be the same or different, but in either case, it is preferable that the above-mentioned range is satisfied.

[0046] The basis weight W1 of the fiber aggregates 11 in the high basis weight region 45 is preferably 10 g / m 2 More preferably, 20 g / m 2 More preferably, it is 400 g / m 2 Less than 350 g / m 2Such a basis weight reduces the gap between the absorbent article and the body, thereby preventing leakage, and also allows the absorbent article to maintain high compression recovery even when it has absorbed liquid.

[0047] The basis weight W2 of the water-absorbent fiber 12 in the high basis weight region 45 is preferably 10 g / m 2 More preferably, 20 g / m 2 More preferably, it is 300 g / m 2 Less than 200 g / m 2 With such a basis weight, the absorbent fibers 12 wetted with discharged body fluids do not inhibit the compression recovery of the fiber mass 11, and it is possible to simultaneously suppress side leakage of body fluids and improve the ability to recover from a deformed state to a predetermined shape.

[0048] The W1 / W2 ratio in the lateral central region 4C is preferably 0 or more, more preferably 0.5 or more, and preferably 1.0 or less or less than 1.0, more preferably 0.8 or less, provided that it is lower than the W1 / W2 ratio in the high basis weight region 45. In other words, the absorbent core 40 in the lateral central region 4C may be in an embodiment in which no fiber agglomerates 11 are present and the absorbent fibers 12 are present, or in which the fiber agglomerates 11 and the absorbent fibers 12 are present in a range that satisfies the above-mentioned W1 / W2 ratio. By having such a W1 / W2 ratio in the lateral central region 4C, it is possible to improve the fit and the compression recovery during absorption without impairing the liquid absorption performance.

[0049] When the fiber agglomerates 11 are present in the lateral central region 4C, the basis weight W1 of the fiber agglomerates 11 in the lateral central region 4C is preferably 10 g / m 2 More preferably, 20 g / m 2 More preferably, it is 400 g / m 2 Less than 350 g / m 2 Such a basis weight can fill the gap between the wearer and the garment, providing a good fit, and can also improve compression recovery when absorbing liquid.

[0050] The basis weight W2 of the absorbent fiber 12 in the lateral central region 4C is preferably 100 g / m 2 More preferably, 200 g / m 2 or more, preferably 1000 g / m 2 Less than 800g / m 2 By using such a basis weight, high liquid absorbency can be achieved at the center of the absorbent article.

[0051] The ratio of the length of one lateral region 4S along the lateral direction Y to the total length of the absorbent body 4 along the lateral direction Y is preferably 20% or more and 40% or less. With this configuration, it is possible to achieve high fit and width-direction compression recovery in the lateral region 4S while maintaining the absorbency of the lateral central region 4C.

[0052] When fiber agglomerates 11 are present in the lateral central region 4C, the ratio of the mass of fiber agglomerates 11 present in the high basis weight region 45 to the mass of fiber agglomerates 11 present in the lateral central region 4C is preferably at least 1, more preferably at least 2, and preferably at most 20, more preferably at most 10. This ratio allows the lateral side regions 4S to exhibit high fit and width-direction compression recovery while maintaining the high liquid absorbency of the lateral central region 4C.

[0053] 3 shows another embodiment of a cross section along the transverse direction Y of the longitudinal central region M of the napkin 1. As shown in the figure, it is preferable that the maximum thickness H1 of both high basis weight regions 45, 45 of the absorbent body 4 in the napkin 1 is greater than the maximum thickness H2 of the transverse central region 4C of the absorbent body 4. With this configuration, since the high basis weight region 45 is located on the transverse outward side, the flexibility, cushioning properties, fit, and compression recovery of the absorbent body 4 against an external force inward in the transverse direction Y can be further improved, and the high basis weight region 45 can act as a leakage barrier to effectively prevent excreted body fluids from leaking outward in the transverse direction.

[0054] To achieve such a configuration, for example, the fiber stacking order and fiber stacking amount on a rotating drum of a fiber stacking device that manufactures the absorbent core 40 can be appropriately adjusted. The absorbent core 40 manufactured in this manner is configured so that the maximum thickness of the high basis weight region in the absorbent core 40 is greater than the maximum thickness of the lateral central region of the core 40. This also makes the maximum thickness H1 of the high basis weight region 45 of the absorbent body 4 greater than the maximum thickness H2 of the lateral central region 4C of the absorbent body 4.

[0055] When the maximum thickness of the high basis weight region 45 is higher than the maximum thickness of the lateral central region 4C of the absorbent body 4, the absorbent body 4 has a region where the thickness increases continuously or stepwise when viewed outward in the lateral direction Y from the lateral central region 4C toward the high basis weight region 45. This region is a boundary region where differences in thickness, density, or stiffness of the absorbent body 4 occur. From the viewpoint of effectively preventing unintended destruction of the absorbent body 4 and twisting during wear, it is preferable that the absorbent body 4 has a region where the thickness increases continuously at this boundary region when viewed along the lateral direction Y from the lateral central region 4C of the absorbent body 4 toward the high basis weight region 45. In this case, the high basis weight region 45 may have a skin-facing surface composed only of an inclined surface, or may have an inclined surface and a flat region on the outer side of the inclined surface in the lateral direction Y.

[0056] The maximum thickness H1 of each of the high basis weight regions 45, 45 of the absorbent body 4 is preferably 2 mm or more, more preferably 3 mm or more, and preferably 10 mm or less, more preferably 7 mm or less. Such a thickness makes it possible to suppress side leakage of bodily fluids without impairing the wearing comfort.

[0057] The maximum thickness H2 of the lateral central region 4C of the absorbent body 4 is preferably 1 mm or more, more preferably 2 mm or more, and is preferably 8 mm or less, more preferably 6 mm or less. Such a thickness allows the absorbent body 4 to exhibit high liquid absorbency without impairing the comfort of wearing the absorbent body. It is preferable that the maximum thickness H2 satisfies the above range even when a thick portion, which will be described later, is formed.

[0058] The maximum thickness of the absorbent body 4 can be measured by the following method. The absorbent body to be measured is placed on a horizontal surface without any wrinkles or bends, and the measurement target portion is cut out from the absorbent body to be used as a measurement sample. 2 The thickness is measured under a load of 5 cN / cm. Specifically, for example, a thickness gauge, PEACOCK DIAL UPRIGHT GAUGES R5-C (manufactured by OZAKI MFG.CO.LTD.), is used to measure the thickness. At this time, a load of 5 cN / cm is applied between the tip of the thickness gauge and the measurement sample. 2 A plate (an acrylic plate with a thickness of about 5 mm) with a circular or square shape in plan view, the size of which is adjusted so that the maximum thickness is measured. In the thickness measurement, 10 arbitrary points on the measurement sample are measured, and the thickest value among the 10 points is defined as the maximum thickness H1 or maximum thickness H2 described above.

[0059] As described above, the high basis weight region 45 is configured to have a higher W1 / W2 ratio than the lateral central region 4C of the absorbent body 4, and in addition to this, as shown in Fig. 4, the absorbent body 4 in the napkin 1 is preferably configured to include a high rigidity region 48 having a higher rigidity than other parts in the high basis weight region 45. The high rigidity region 48 is also preferably located so as to include a side edge 4a along the longitudinal direction X of the absorbent body 4. The high rigidity region 48 is approximately uniformly present in the thickness direction Z of the absorbent body 4. Similar to the high basis weight region 45, a pair of high stiffness regions 48 are present at least in the longitudinal central region M, and may be present only in the longitudinal central region M, or may extend in the longitudinal direction X to include the longitudinal central region M and the front region F and the rear region R. In either case, it is preferable that the width (length along the lateral direction Y) of the high stiffness region 48 is constant in order to reduce unintended deformation and twisting.

[0060] By forming the high stiffness region 48 to include the lateral outer end of the absorbent body 4, the flexibility and cushioning of the absorbent body 4 are sufficiently maintained due to the fiber agglomerations present in the high basis weight region 45, while compressive deformation due to an external force inward in the lateral direction Y caused by being pinched between both thighs when the napkin 1 is worn is reduced, making it possible to increase conformability and improve fit when worn. Furthermore, when the above-mentioned external force is released or weakened, compression recovery and shape retention can be easily and sufficiently achieved, making it possible to more effectively reduce unintended deformation and twisting when the napkin 1 is worn. In particular, by adopting this in combination with a configuration in which the maximum thickness H1 of the high basis weight region 45 is made higher than that of other portions of the absorbent body 4, even if the napkin 1 is deformed by external forces generated when worn, the high rigidity region 48 can exhibit resistance to the external forces and act as a leak-proof wall, thereby effectively preventing excreted body fluids from leaking laterally outward.

[0061] In order to provide the absorbent body 4 with a high stiffness region 48, for example, as shown in Fig. 4, at least one of the fiber agglomerates 11 and the absorbent fibers 12, which are the constituent materials of the absorbent core 40, may be arranged so that its basis weight is higher than that of the other high basis weight regions. In addition to this, or instead of this, when the absorbent core 40 contains a water-absorbent polymer, the basis weight of the water-absorbent polymer may be arranged so that it is higher than that of the other high basis weight regions, or a material other than the fiber agglomerates 11, the absorbent fibers 12, and the water-absorbent polymer may be used as the constituent material of the absorbent core 40. Examples of other materials capable of exhibiting high stiffness include polyvinyl alcohol, polyurethane, and polystyrene foam resin. In either case, the high stiffness region 48 must satisfy the W1 / W2 ratio in the high basis weight region 45 described above.

[0062] The stiffness of the high stiffness region 48 in the high basis weight region 45 and the stiffness of the region other than the high stiffness region 48 can be measured by the following method. Specifically, it is generally known that it can be expressed as a measurement value using the KES (Kawabata Evaluation System) manufactured by Kato Tech Co., Ltd. (Reference: Standardization and Analysis of Texture Evaluation (2nd Edition), author Kawabata Toshio, published July 10, 1980). Specifically, the compression work load can be measured using the automated compression tester KES-G5 manufactured by Kato Tech Co., Ltd. The measurement procedure is as follows. The sample "absorbent article having an absorbent body" is attached to the test table of the compression test device. Next, the sample is compressed to a size of 2 cm 2 The specimen is compressed between steel plates with circular flat surfaces. The compression speed is 0.02cm / sec, and the maximum compression load is 490mN / cm. 2 The recovery process is also measured at the same speed.

[0063] The compression work (WC) and recovery work (WC') are expressed by the following equations. a is the load during measurement (compression process) (mN / cm 2 ), P b is the load during measurement (recovery process) (mN / cm 2 The compression work (WC) and recovery work (WC') are measured under the above-mentioned measurement conditions at a load of 0 mN / cm 2 to 490mN / cm 2 In other words, in the following equation, T o =0mN / cm 2 , T m =490mN / cm 2 The values ​​were measured and calculated by substituting the above.

[0064] The compression work load is a measure of the cushioning properties of the absorbent, and the larger the WC value, the higher the cushioning properties and the higher the rigidity. In other words, the rigidity in this specification corresponds to the compression work load (WC) value. The recovery work load is a measure of the degree of recovery when the absorbent is compressed and released from the compressed state, and the larger the WC' value, the higher the compression recovery properties and the less likely it is to twist.

[0065]

number

[0066]

number

[0067] In order to more effectively obtain the effects of the high-rigidity region 48, the rigidity N1 of the high-rigidity region 48 is preferably 120 mN·cm / cm 2 More than 300mN cm / cm 2 The following is the result.

[0068] The stiffness N2 of the region other than the high stiffness region 48 in the high basis weight region 45 is preferably 80 mN·cm / cm from the viewpoint of preferentially deforming the high basis weight region 45 not including the high stiffness region 48 when worn to improve fit and width direction compression recovery. 2 More than 150mN cm / cm 2 The following is the result.

[0069] In the high basis weight region 45, the ratio (N1 / N2) of the rigidity N1 of the high rigidity region 48 to the rigidity N2 of the region other than the high rigidity region 48 is preferably 0.5 or less, more preferably 0.3 or less, and the lower the ratio the better, but it is practical to set the ratio to more than 0. With such a ratio, the high basis weight region 45 not including the high rigidity region 48 is preferentially deformed, improving the fit and widthwise compression recovery.

[0070] 5 shows yet another embodiment of a cross section along the horizontal direction Y of the longitudinal central region M of the napkin 1. As shown in the figure, the napkin 1 preferably has a plurality of small recesses 49 at a position inward in the horizontal direction Y from the high basis weight region 45 of the absorbent body 4. It is also preferable that the depth of each of these small recesses 49 is smaller than the depth of the recessed portion 7. With this configuration, it is possible to increase the rigidity of the entire absorbent body 4 while maintaining a sufficient fit when worn, and to more effectively reduce unintended deformation and twisting when the napkin 1 is worn.

[0071] The small recesses 49 in this embodiment are formed in a position inward in the lateral direction Y from the lateral inner end of the high basis weight region 45, and in the lateral central region 4C. The small recesses 49 are formed by the absorbent core 40 and the core wrap sheet 41 constituting the absorbent body 4 being integrally recessed from the skin-facing surface toward the non-skin-facing surface side, and the topsheet 2 is not recessed at the position where the small recesses 49 exist. The small recesses 49 may be formed in a plurality of continuous or broken lines extending in one direction in a plan view, or may be formed in a plurality of scattered dots. When the high basis weight region 45 is not formed over the entire lateral side region 4S in the lateral direction Y, a small recess 49 is not prevented from being further formed at a position inward in the lateral direction Y from the lateral inner end of the high basis weight region 45 and outward in the lateral direction Y from the recess 7.

[0072] The small recesses 49 thus formed are areas in the thickness direction Z where the constituent material has a higher density than areas in the absorbent body 4 where the small recesses 49 and the recesses 7 are not formed. Also, the areas in the absorbent body 4 where the small recesses 49 are formed are configured such that the density of the constituent material is lower than the density of the constituent material in the thickness direction Z of the recesses 7. By providing the absorbent body 4 with these areas of different density, the rigidity of the entire absorbent body 4 is increased, making it possible to effectively reduce unintended deformation and twisting when the napkin 1 is worn. Such small recesses 49 can be formed, for example, by subjecting the absorbent body 4 before the top sheet 2 is placed thereon to a compression process such as round embossing or pin embossing, with the degree of pressure being less than that used when forming the recessed portion 7.

[0073] In this embodiment, the small recesses 49 are formed only on the skin-facing surface of the absorbent body 4. In addition to this, or instead of this, a back surface small recess may be formed that is recessed from the non-skin-facing surface of the absorbent body 4 toward the skin-facing surface side (not shown). The back surface small recesses have approximately the same shape and size as the small recesses 49 in a plan view, and are preferably formed at positions that overlap the small recesses 49 in a plan view in order to prevent deformation and twisting during wear. The back surface small recesses can be suitably formed by embossing from the non-skin-side core wrap sheet side in the same manner as the small recesses 49. For points that are not specifically described regarding the back surface small recesses, the description regarding the small recesses 49 applies as appropriate.

[0074] Regarding the positional relationship between the absorbent body 4 and the adhesive portion 9, it is preferable that the adhesive portion 9 is disposed at a position that does not overlap with the high basis weight region 45 in the absorbent body 4 in a plan view. With such a configuration, the high basis weight region 45 is not fixed to the clothing and can exist in a state with a relatively high degree of freedom of movement, so that the ability to follow the external force in the lateral direction Y that occurs when the napkin 1 is worn can be made even higher, and the fit when worn can be further improved. In addition, when the above-mentioned external force is released or weakened, the compression recovery and shape retention of the absorbent body 4 can be improved in the lateral direction of the absorbent body 4 without being affected by the adhesive portion 9, and unintended deformation and twisting when the napkin 1 is worn can be further reduced.

[0075] 2 to 6, the adhesive portions 9 in this embodiment are intermittently arranged in the lateral central region 4C, which is located inward in the lateral direction Y from the high basis weight region 45. Alternatively, the adhesive portions 9 may be arranged over the entire area located inward in the lateral direction Y from the high basis weight region 45. Furthermore, for example, when the high basis weight region 45 is formed only in the longitudinal central region M, the adhesive portions 9 may be arranged continuously or intermittently in at least one of the front region F and the rear region R in addition to or instead of the position located inward in the lateral direction Y from the high basis weight region 45.

[0076] Fig. 6 shows another embodiment of a cross section taken along the transverse direction Y of the longitudinal central region M of the napkin 1. As shown in the figure, the absorbent body 4 in the napkin 1 preferably has a thick portion 50 in the transverse central region 4C that is thicker than the peripheral portion of the transverse central region 4C. In this case, the thick portion 50 is formed at least in the longitudinal central region M, and is disposed in a portion facing the excretory part of the wearer, such as the vaginal opening.

[0077] In this embodiment, the central portion in the lateral direction Y in the lateral central region 4C of the absorbent core 40 is the thick portion 50, which is formed so as to protrude toward the skin-facing surface side of the napkin 1. In addition, the portion other than the thick portion 50 in the lateral central region 4C is a thin portion 51 having a smaller thickness than the thick portion 50. The thick portion 50 is formed by increasing the basis weight of the constituent material of the absorbent core 40, such as absorbent fibers, and has a higher rigidity than the thin portion 51 due to the larger basis weight of the forming material of the absorbent core 40. Therefore, by having such a configuration, the rigidity of the absorbent body 4 can be increased, and unintended deformation and twisting when the napkin 1 is worn can be more effectively reduced. In addition, the absorption and retention of excreted body fluids is further improved. As long as the effects of the present invention are achieved, the thick portion 50 may be formed so as to protrude toward the non-skin-facing surface side of the napkin 1.

[0078] The thickness of the thick portion 50 in the absorbent body 4 can be set in the same range as the maximum thickness H2 of the lateral central region 4C of the absorbent body 4 described above. The thickness of the thin portion 51 is preferably 1 mm or more, more preferably 2 mm or more, and is preferably 8 mm or less, more preferably 6 mm or less.

[0079] When the high basis weight region 45 is formed only in the longitudinal central region M of the absorbent body 4, the absorbent body 4 preferably has one or more groove-shaped recesses 42 that have openings and extend in a predetermined direction on at least one of the skin-facing and non-skin-facing surfaces of the absorbent core 40 as shown in Fig. 7. The groove-shaped recesses 42 are spaces where no constituent material of the absorbent core 40 is present. Here, "no constituent material is present" includes not only a form where no constituent material is present at all, but also a form where a very small amount of core-forming material is present that can be recognized as a space.

[0080] In the case where the high basis weight region 45 is formed only in the longitudinal central region M of the absorbent body 4, the groove-shaped recesses 42 are further formed, and due to the presence of the groove-shaped recesses 42 in the front region F and / or the rear region R, which can act as bending induction parts (flexible shafts), the absorbent core 40 becomes more likely to deform along the body shape of the wearer when the napkin 1 is worn. In addition, body fluids such as menstrual blood excreted by the wearer of the napkin 1 are quickly absorbed and diffused in the plane direction of the absorbent core 40, and at that time, the groove-shaped recesses 42 function as a conduction path for the body fluid and a stock layer that temporarily holds the body fluid, promoting the diffusion of the body fluid in the plane direction. In addition, since the absorbent core 40 contains fiber agglomerates 11 that can contribute to improving the flexibility, cushioning properties, compression recovery properties, and shape retention properties, the wearing comfort and fit are further improved and the napkin is less likely to twist.

[0081] The groove-like recess 42 is present in at least one of the front region F and the rear region R of the absorbent core 40 in the absorbent body 4. In addition, in the vertical central region M of the absorbent core 40 in the absorbent body 4, the groove-like recess 42 may or may not be present.

[0082] The groove-shaped recess 42 may be formed as a non-penetrating type so as not to penetrate the absorbent core 40 in the thickness direction, or may be formed as a penetrating type so as to penetrate the absorbent core 40 in the thickness direction. When the groove-shaped recess 42 is formed as a non-penetrating type, the groove-shaped recess 42 may have an opening on the skin-facing surface of the absorbent core 40 and a bottom on the opposite side to the opening, or may have an opening on the non-skin-facing surface of the absorbent core 40 and a bottom on the opposite side to the opening. In addition, when the groove-like recess 42 is of the non-through type, the surface of the absorbent core 40 on the side having the opening of the groove-like recess 42 has an uneven shape composed of recesses formed by the openings of the groove-like recess 42 and a plurality of protrusions formed by the small absorbent portions 43, and is an uneven surface. On the other hand, the surface of the absorbent core 40 on the side having the opening of the groove-like recess 42 is a flat surface on which the groove-like recess 42 is not formed.

[0083] 7, the groove-like recesses 42 are configured to include vertical recesses 42X extending in the vertical direction X and horizontal recesses 42Y extending in a direction intersecting (perpendicular to) the vertical recesses 42X, which are present throughout both the front region F and the rear region R of the absorbent core 40. Meanwhile, the groove-like recesses 42 are not present in the vertical central region M. Moreover, the groove-like recesses 42 in this embodiment have openings on the skin-facing surface of the absorbent core 40, and are formed so that neither of them penetrates the absorbent core 40 in the thickness direction. This allows bodily fluid excreted on the skin-facing side of the absorbent 4 to be quickly absorbed in the groove-like recesses 42 while being diffused in the planar direction, further improving fluid absorbency. In addition, the groove-like recesses 42 are flexible shafts, which improves the ability to follow the wearer's movements, and the absorbent 4 has excellent flexibility, cushioning properties, and compression recovery.

[0084] When the groove-like recesses 42 are formed in the front region F and the rear region R of the absorbent core 40, the absorbent core 40 located in the front region F and the absorbent core 40 located in the rear region R may each independently be configured to contain fiber agglomerates 11 and water-absorbent fibers 12, or may be configured in a mode not containing fiber agglomerates 11. In either case, the absorbent core 40 located in the front region F and the absorbent core 40 located in the rear region R are configured to have a W1 / W2 ratio lower than that of the high basis weight region 45.

[0085] When the absorbent core 40 further contains a water-absorbent polymer, the water-absorbent polymer is present as a plurality of small pieces or particles in the absorbent core 40, and mainly contributes to improving the liquid absorbency in the absorbent core 40. The shape of the small pieces of the water-absorbent polymer is not particularly limited, and may be, for example, spherical, clumpy, bale-shaped, fibrous, or irregular. As the water-absorbing polymer, generally, a polymer or copolymer of acrylic acid or an alkali metal salt of acrylic acid can be used. Examples thereof include polyacrylic acid and its salts, and polymethacrylic acid and its salts, specifically, partial sodium salts of acrylic acid polymers such as AQUALIC CA and AQUALIC CAW (both manufactured by Nippon Shokubai Co., Ltd.).

[0086] When the absorbent core 40 further contains a water-absorbing polymer, the average particle size of the water-absorbing polymer is preferably 10 μm or more, more preferably 100 μm or more, and preferably 1000 μm or less, more preferably 800 μm or less. When the absorbent core 40 further contains a water-absorbing polymer, the basis weight of the water-absorbing polymer in the absorbent core 40 is preferably 5 g / m 2 More preferably, 10 g / m 2 More than 200 g / m 2 Less than 100 g / m 2 The following is the result.

[0087] The depth of the recess 7 (length along the thickness direction Z) is preferably 0.01 mm or more, more preferably 0.1 mm or more, and preferably 2.0 mm or less, more preferably 1.0 mm or less. This depth improves the moldability of the absorbent body 4 and can suppress the diffusion of body fluids in the width direction of the product.

[0088] When the small recesses 49 are formed, the depth of the small recesses 49 (length along the thickness direction Z) is preferably 0.01 mm or more, more preferably 0.05 mm or more, and preferably 1.0 mm or less, more preferably 0.8 mm or less. This depth improves the formability of the absorbent body 4 and allows bodily fluids to be transferred quickly from the topsheet 2 to the absorbent body 4.

[0089] As is clear from the above description, the present specification discloses not only absorbent articles but also matters relating to the absorbent body itself. In detail, the absorbent body has a pair of main surfaces, and has a first direction and a second direction perpendicular to the first direction in a plan view. The absorbent body preferably has a shape that is long in the first direction. The main surfaces of the absorbent body are surfaces that form the skin-facing surface and the non-skin-facing surface of the absorbent body, respectively, when the absorbent body is incorporated as a component of an absorbent article. The first direction and the second direction can be appropriately interpreted as the longitudinal direction X and the lateral direction Y in the above-mentioned absorbent article. The other explanations regarding the absorbent body 4 are as described above and may be appropriately applied, and the configurations thereof may be employed alone or in combination.

[0090] For convenience of explanation, the absorbent article of the present invention has been described using a sanitary napkin as an example, but it broadly includes articles used to absorb body fluids discharged from the human body (urine, loose stools, menstrual blood, sweat, etc.). The absorbent article includes, in addition to the above-mentioned sanitary napkin, sanitary shorts, so-called open-type disposable diapers having fastening tapes, pants-type disposable diapers, incontinence pads, etc. In particular, the absorbent body 4 having the above-mentioned configuration is applicable to each of the above-mentioned absorbent articles including the sanitary napkin.

[0091] Although the present invention has been described based on the preferred embodiments, the present invention is not limited to the above-described embodiments. [Explanation of symbols]

[0092] 1. Sanitary napkins (absorbent articles) 2 Surface sheet 3 Back sheet 4. Absorber 4C Horizontal central area 4S Lateral area 40 Absorbent Core 41 Core wrap sheet 42 Groove-shaped recess 45 High basis weight area 48 High rigidity area 49 Small recess 50 Thick part 6 Side seat 7,7X,7Y recessed part 9 Adhesive part 11 Fiber mass 12 Absorbent fibers F front area M Vertical center area R rear area X vertical direction Y Horizontal Z thickness direction

Claims

1. An absorbent article having a vertical direction corresponding to a front-to-rear direction of a wearer and a horizontal direction perpendicular thereto, the article having a vertical central region arranged to face an excretory part of the wearer, a front region arranged vertically forward of the vertical central region, and a rear region arranged vertically rearward of the vertical central region, the absorbent article comprising an absorbent body, The absorbent body includes a fiber mass including synthetic fibers and a water-absorbent fiber, The absorbent body has a pair of recesses extending in the longitudinal direction from the skin-facing surface toward the non-skin-facing surface, When the absorbent body is divided into a lateral central region located laterally inward from each of the recesses and a pair of lateral side regions located laterally outward from each of the recesses, A high basis weight region is formed in each of the lateral side regions, in which the ratio of the basis weight of the fiber mass to the basis weight of the water-absorbent fiber is higher than the ratio in the lateral central region, The high basis weight region is located at least in the longitudinal central region so as to include side edges of the absorbent body along the longitudinal direction.

2. 5 cN / cm ２ 2. The absorbent article according to claim 1, wherein the maximum thickness of both high basis weight regions is greater than the maximum thickness of the lateral central region of the absorbent body under a load of 100 mm.

3. The high basis weight region includes a high rigidity region having a rigidity higher than that of other portions of the high basis weight region, The absorbent article according to claim 1 or 2, wherein the high stiffness region is positioned so as to include the side edge along the longitudinal direction of the absorbent body.

4. The absorbent article according to any one of claims 1 to 3, wherein the absorbent body has a plurality of small recesses, the depth of which is smaller than the depth of the recessed portion, located laterally inward of the high basis weight region in the absorbent body.

5. Further comprising a top sheet arranged on the skin-facing side of the absorbent body, The absorbent article according to any one of claims 1 to 4, wherein the recessed portion is formed by integrally recessing the topsheet and the absorbent body.

6. The absorbent further comprises a back sheet disposed on the non-skin facing side of the absorbent body, and an adhesive portion disposed on the non-skin facing side of the back sheet, The absorbent article according to any one of claims 1 to 5, wherein the adhesive portion is disposed at a position that does not overlap the high basis weight region in a plan view.

7. An absorbent body having a pair of main surfaces and having a first direction and a second direction perpendicular to the first direction in a plan view, The absorbent body includes a fiber mass including synthetic fibers and a water-absorbent fiber, The absorbent body has a pair of recessed portions formed therein, the recessed portions being recessed in a thickness direction from one main surface to the other main surface and extending in the first direction, When the absorbent body is divided into a second direction central region located inward in the second direction from each of the recesses and a pair of second direction lateral regions located outward in the second direction from each of the recesses, A high basis weight region is formed in each of the second direction side regions, in which the ratio of the basis weight of the fiber aggregate to the basis weight of the water-absorbent fiber is higher than the ratio in the second direction central region, The high basis weight region is located at least in a central region in the first direction so as to include a side edge along the first direction.

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