Absorbent article

Abstract

To provide an absorbent article which secures excellent absorption performance while reducing unnatural feeling of the crunchy sense of touch of a high absorbent polymer.SOLUTION: In an absorbent article (1), absorbent cores (21 to 23) have: a skin side layer (21) which has a first thickness (t1), and in which a volume occupied by a high absorbent polymer (SAP) is larger than a volume occupied by a liquid absorbent fiber (201); an intermediate layer (22) which has a second thickness (t2), and in which a volume occupied by the liquid absorbent fiber (201) is larger than a volume occupied by the high absorbent polymer (SAP); and a non-skin side layer (23) which has a third thickness (t3), and in which a volume occupied by the high absorbent polymer (SAP) is larger than a volume occupied by the liquid absorbent fiber (201), wherein a total water content of the high absorbent polymer existing in the skin side layer (21) and a total water content of the high absorbent polymer existing in the non-skin side layer (23) are different from each other.SELECTED DRAWING: Figure 4

Description

[Technical Field]

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

[0002] Various improvements have been made to absorbent articles to ensure thinness and comfortable wear while maintaining absorption performance. For example, Patent Document 1 discloses an absorbent article including an absorbent core containing superabsorbent polymer particles and consisting of a first layer and a second layer, in which the first layer has a plurality of grooves including a plurality of main grooves extending in the longitudinal direction and penetrating in the thickness direction, and a plurality of bases, the main grooves and bases extending alternately in the lateral direction, and the second layer has a plurality of main groove corresponding portions at positions overlapping with the main grooves in the thickness direction and a plurality of base corresponding portions at positions overlapping with the bases in the thickness direction. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6320467 Summary of the Invention [Problem to be solved by the invention]

[0004] In the absorbent core of Patent Document 1, bodily fluids permeate from the multiple main groove-corresponding portions of the absorbent core to the multiple main grooves, are drawn into the adjacent bases, and when the bases are no longer able to hold the fluid, they are sucked up by the multiple base-corresponding portions. This cycle of absorption allows for repeated absorption, resulting in excellent liquid diffusion and suppression of liquid return. While excellent absorption performance, like that of the absorbent core of Patent Document 1, can ensure absorbency, it is difficult to simultaneously achieve a thin absorbent core. For example, if an absorbent core contains pulp fibers and a superabsorbent polymer, reducing the proportion of pulp fibers and increasing the proportion of superabsorbent polymer in the absorbent core to improve absorbency can result in the superabsorbent polymer feeling more gritty to the touch, and the superabsorbent polymer may be more susceptible to crumbling due to reduced entanglement with the pulp fibers. Conversely, reducing the proportion of superabsorbent polymer to reduce the gritty feeling and achieve a thinner product can make it difficult to ensure absorbency. Therefore, there is a need to develop an absorbent body that ensures absorbency while reducing the uncomfortable gritty feel of superabsorbent polymers.

[0005] The present invention has been made in consideration of the above-mentioned problems, and its object is to provide an absorbent article that ensures good absorption performance while reducing the discomfort caused by the gritty feel of superabsorbent polymers. [Means for solving the problem]

[0006] The main invention for achieving the above-mentioned object is an absorbent article having an absorbent core which, in an unfolded state, has a longitudinal direction, a width direction, and a thickness direction which are perpendicular to each other, and which contains liquid-absorbent fibers and a superabsorbent polymer, wherein the absorbent core has a skin-side layer having a first thickness and in which the volume occupied by the superabsorbent polymer is larger than the volume occupied by the liquid-absorbent fibers, an intermediate layer having a second thickness and in which the volume occupied by the liquid-absorbent fibers is larger than the volume occupied by the superabsorbent polymer, and a non-skin-side layer having a third thickness and in which the volume occupied by the superabsorbent polymer is larger than the volume occupied by the liquid-absorbent fibers, wherein the intermediate layer is located closer to the skin side in the thickness direction than the skin-side layer, and the non-skin-side layer is located closer to the skin side in the thickness direction than the intermediate layer, and the total water retention capacity of the superabsorbent polymer present in the skin-side layer is different from the total water retention capacity of the superabsorbent polymer present in the non-skin-side layer. Other features of the present invention will become apparent from the description of this specification and the accompanying drawings. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide an absorbent article that ensures good absorption performance while reducing the discomfort caused by the gritty feel of superabsorbent polymers. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic perspective view of a diaper 1. [Figure 2] 1 is a plan view of the diaper 1 in an unfolded and stretched state, as viewed from the skin side. [Figure 3] FIG. 3 is a schematic cross-sectional view taken along the center line CL in FIG. 2. [Figure 4] FIG. 2 is a cross-sectional view of an absorbent body 20 according to the present embodiment. [Figure 5] FIG. 2 is a plan view of absorbent cores 21 to 23 superimposed on one another. [Figure 6] 6A is a plan view of the skin side layer 21 and the intermediate layer 22, and FIG. 6B is a plan view of the non-skin side layer 23. As shown in FIG. [Figure 7]FIG. 2 is a schematic plan view of the absorbent body 20 as seen from the skin side. [Figure 8] FIG. 2 is a partially enlarged plan view showing the adhesive HMA that bonds the core wrap sheet 25 and the skin side upper layer 24 (skin side layer 21). [Figure 9] The image of the non-skin side of the core wrap sheet 25 in the inner region UR of the diaper 1 before use is taken. [Figure 10] 10A and 10B are cross-sectional views of modified examples of the absorbent cores 21 to 24. FIG. [Figure 11] 10A and 10B are cross-sectional views of modified examples of absorbent cores 21 to 23. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0009] At least the following matters will become clear from the description of this specification and the accompanying drawings. (Aspect 1) An absorbent article having an absorbent core which, in an unfolded state, has a longitudinal direction, a width direction, and a thickness direction which are perpendicular to each other, and which contains liquid-absorbent fibers and a superabsorbent polymer, wherein the absorbent core has a skin-side layer having a first thickness and in which the volume occupied by the superabsorbent polymer is larger than the volume occupied by the liquid-absorbent fibers, an intermediate layer having a second thickness and in which the volume occupied by the liquid-absorbent fibers is larger than the volume occupied by the superabsorbent polymer, and a non-skin-side layer having a third thickness and in which the volume occupied by the superabsorbent polymer is larger than the volume occupied by the liquid-absorbent fibers, wherein the intermediate layer is located closer to the skin side in the thickness direction than the skin-side layer, and the non-skin-side layer is located closer to the skin side in the thickness direction than the intermediate layer, and the total water retention capacity of the superabsorbent polymer present in the skin-side layer is different from the total water retention capacity of the superabsorbent polymer present in the non-skin-side layer.

[0010] According to the first aspect, the layer with a lower total water retention capacity can prevent the superabsorbent polymer from swelling and inhibiting liquid absorption, allowing excreted liquid to easily diffuse. Furthermore, the layer with a lower total water retention capacity has a smaller total volume of superabsorbent polymer after absorbing water, resulting in a pleasant feel against the skin and a less gritty texture. The layer with a higher total water retention capacity can firmly absorb and retain excreted liquid, ensuring absorbency. Therefore, even after the absorbent core has absorbed excreted liquid, absorbency can be ensured while reducing the uncomfortable feel.

[0011] (Aspect 2) In the absorbent article according to aspect 1, the total water retention capacity of the superabsorbent polymer present in the non-skin side layer is greater than the total water retention capacity of the superabsorbent polymer present in the skin side layer.

[0012] According to the second aspect, rewetting can be suppressed by retaining a certain amount of water in the skin-side layer and retaining more water in the non-skin-side layer. The skin-side layer is less likely to swell even after absorption, and the gritty feel of the superabsorbent polymer is less likely to be felt. Furthermore, because the skin-side layer retains less water, absorption is less likely to be inhibited by the superabsorbent polymer, and liquid can easily migrate to the middle layer and non-skin-side layer. Furthermore, excreted liquid temporarily stored in the middle layer, which has a high volumetric occupancy rate of liquid-absorbent fibers, is ultimately firmly absorbed and retained in the non-skin-side layer, which has a high total water retention capacity, ensuring absorbency.

[0013] (Aspect 3) An absorbent article having an absorbent core which, in a developed state, has a longitudinal direction, a width direction, and a thickness direction which are orthogonal to one another, and which contains a liquid-absorbent fiber and a superabsorbent polymer, wherein the absorbent core has a skin-side layer having a first thickness, and in which a volume occupied by the superabsorbent polymer is larger than a volume occupied by the liquid-absorbent fiber, an intermediate layer having a second thickness, and in which a volume occupied by the liquid-absorbent fiber is larger than a volume occupied by the superabsorbent polymer, and a non-skin-side layer having a third thickness, and in which a volume occupied by the superabsorbent polymer is larger than a volume occupied by the liquid-absorbent fiber, the non-skin-side layer is located closer to the skin in the thickness direction than the intermediate layer, the non-skin-side layer is located closer to the skin in the thickness direction than the intermediate layer, the average value of the total area occupied by the superabsorbent polymer per unit area in a cross section along the thickness direction of the skin-side layer is different from the average value of the total area occupied by the superabsorbent polymer per unit area in a cross section along the thickness direction of the non-skin-side layer, and a skin-side upper layer is provided closer to the skin in the thickness direction than the skin-side layer, the skin-side upper layer being thinner than the first thickness and having a volume occupied by the liquid-absorbent fiber greater than the volume occupied by the superabsorbent polymer.

[0014] According to aspect 3, a layer with a small average total area occupied by SAPs per unit area is less likely to feel gritty to the touch, and if such a layer is the skin-facing layer, the wearer is less likely to feel an uncomfortable feel from the SAPs, and if it is a non-skin-facing layer, the person changing the article is less likely to feel an uncomfortable feel from the SAPs. A layer with a large average total area occupied by SAPs per unit area improves absorbency, and if such a layer is the skin-facing layer, the SAPs can retain excreted fluid and suppress rewet, and if it is a non-skin-facing layer, the water retention ability is improved. Furthermore, the presence of the skin-side upper layer, which has a high volumetric ratio of liquid-absorbent fibers, further reduces the wearer's feeling of unevenness caused by the superabsorbent polymer. Furthermore, the liquid-absorbent fibers in the skin-side upper layer make it difficult for the superabsorbent polymer in the skin-side layer to roll around within the layer, preventing a deterioration in the feel.

[0015] (Aspect 4) An absorbent article as described in aspect 3, wherein the average value of the total area occupied by the superabsorbent polymer per unit area in a cross section along the thickness direction of the non-skin side layer is greater than the average value of the total area occupied by the superabsorbent polymer per unit area in a cross section along the thickness direction of the skin side layer.

[0016] According to aspect 4, the average total area occupied by SAP per unit area of the skin-side layer is small, so the wearer is less likely to feel uncomfortable with the gritty feel of SAP. Furthermore, SAP swelling and inhibition of absorption can be prevented, improving the diffusibility of excreted fluids. Even in cases of repeated excretion, the non-skin-side layer, which has a larger average total area occupied by SAP, can absorb and retain more excreted fluids, thereby suppressing rewetting.

[0017] (Aspect 5) This is an absorbent article described in aspect 1 or aspect 2, in which a skin-side upper layer is provided on the skin side of the skin-side layer in the thickness direction, the skin-side upper layer being thinner than the first thickness and in which the volume occupied by the liquid-absorbent fiber is larger than the volume occupied by the superabsorbent polymer.

[0018] According to aspect 5, the thin upper skin-side layer reduces the gritty feel of the superabsorbent polymer. Although it is positioned closer to the skin than the skin-side layer, its thinness reduces rewetting, and its high liquid-absorbent fiber content further improves the absorption of excreted liquid from the skin-side sheet material.

[0019] (Aspect 6) The absorbent article is described in any one of aspects 3 to 5, wherein the skin-side layer has a low-basis weight region in which the absorbent core has a lower basis weight than the surrounding area, and the skin-side upper layer is arranged so as to overlap the low-basis weight region of the skin-side layer when viewed in a plane.

[0020] According to aspect 6, there is a risk that the superabsorbent polymer may shift and infiltrate into the low basis weight region from the periphery of the low basis weight region, but the presence of the skin-side upper layer covering the low basis weight region from the skin side makes it less likely that the superabsorbent polymer contained in the region outside the low basis weight region in the width and length directions will shift, making it easier to maintain the shape of the low basis weight region.

[0021] (Aspect 7) In the absorbent article according to any one of Aspects 1 to 6, the third thickness is greater than the first thickness.

[0022] According to aspect 7, the thinner skin-side layer is thinner after water retention than the non-skin-side layer. This configuration makes it less likely that absorption will be inhibited due to swelling of the superabsorbent polymer, and also makes it less likely that the gritty feel on the skin side caused by the superabsorbent polymer will be worsened.

[0023] (Aspect 8) In the absorbent article according to any one of Aspects 1 to 7, the non-skin side layer has an average basis weight higher than that of the skin side layer.

[0024] According to aspect 8, the skin-side layer having a low average basis weight is less likely to swell after retaining water, and therefore the skin-side layer is less likely to suffer from absorption inhibition due to swelling of the superabsorbent polymer, and the feel against the skin (gritty feeling) is also less likely to deteriorate.

[0025] (Aspect 9) The absorbent article is described in any one of aspects 1 to 8, wherein the skin-side layer has a different type of superabsorbent polymer from the non-skin-side layer, and the superabsorbent polymer contained in the skin-side layer has a slower liquid absorption rate measured by the vortex method than the superabsorbent polymer contained in the non-skin-side layer.

[0026] According to the ninth aspect, excreted liquid is more likely to migrate to the intermediate layer before being absorbed by the superabsorbent polymer in the skin-side layer. This allows for efficient use of the absorbent core, improving absorption performance. By absorbing more liquid in the non-skin-side layer, rewetting of the skin-side layer can be suppressed.

[0027] (Aspect 10) In the absorbent article according to any one of Aspects 1 to 9, the skin side layer and the intermediate layer are laminated adjacent to each other in the thickness direction without an adhesive or a nonwoven fabric therebetween.

[0028] According to the tenth aspect, it is possible to prevent the adhesive or nonwoven fabric from interfering with the transfer of excreted fluid from the skin-side layer to the intermediate layer, thereby increasing the rate of absorption into the intermediate layer.

[0029] (Aspect 11) In the absorbent article according to any one of Aspects 1 to 9, the intermediate layer and the non-skin side layer are laminated adjacently in the thickness direction without an adhesive or nonwoven fabric therebetween.

[0030] According to the eleventh aspect, it is possible to prevent the adhesive or nonwoven fabric from interfering with the transfer of excreted fluid from the intermediate layer to the non-skin side layer, and the rate of absorption into the non-skin side layer is increased.

[0031] (Aspect 12) An absorbent article described in any one of aspects 1 to 11, wherein at least one of the skin-side layer, the intermediate layer, and the non-skin-side layer has a low-basis weight region in which the absorbent core has a lower basis weight than the surrounding area.

[0032] According to the twelfth aspect, excreted liquid is more easily transferred and diffused from the low basis weight region to the layer closer to the skin side, which makes it easier to draw excreted liquid deep into the absorbent core and improves absorbency.

[0033] (Aspect 13) An absorbent article according to any one of aspects 1 to 12, wherein one of the skin-side layer, the intermediate layer, and the non-skin-side layer has a low basis weight region in which the absorbent core has a lower basis weight than the surrounding area, and at least one of the skin-side layer, the intermediate layer, and the non-skin-side layer other than the layer having the low basis weight region has another low basis weight region in which the absorbent core has a lower basis weight than the surrounding area, and when viewed in a plane of the absorbent core, the low basis weight region has a portion that overlaps with the other low basis weight region.

[0034] According to the thirteenth aspect, the overlapping of the low basis weight regions creates a passageway for excreted liquid, facilitating the migration of excreted liquid from one layer with a low basis weight region to another layer with a low basis weight region. This facilitates the drawing of excreted liquid deep into the absorbent core. Furthermore, the low basis weight regions are less likely to inhibit absorption due to swelling of the superabsorbent polymer, promoting liquid permeation without impeding the drawing of liquid.

[0035] (Aspect 14) An absorbent article according to any one of aspects 1 to 13, wherein in the longitudinal center of the absorbent article, the non-skin side layer has a portion whose widthwise length is longer than the widthwise lengths of the skin side layer and the intermediate layer.

[0036] According to Aspect 14, the non-skinside layer absorbs the excreted fluid that is not fully absorbed by the skin-side layer and the intermediate layer, thereby preventing leakage. In addition, the number of layers is partially reduced, which reduces rigidity and improves wearability.

[0037] (Aspect 15) In the absorbent article according to any one of Aspects 1 to 14, the maximum lengths of the skin side layer and the intermediate layer in the width direction are longer than the maximum length of the non-skin side layer.

[0038] According to aspect 15, the skin-side layer and the intermediate layer have a wide width (long maximum length), so that excreted fluid is absorbed and diffused more effectively in the skin-side area than in the non-skin-side layer.

[0039] (Aspect 16) In the absorbent article according to any one of Aspects 1 to 15, the lengths of the skin side layer and the intermediate layer in the longitudinal direction are longer than the length of the non-skin side layer.

[0040] According to aspect 16, if the length of the non-skin side layer is longer, it becomes difficult for excretory fluid to migrate from the skin side beyond the skin side layer and the intermediate layer, but by positioning the skin side layer and the intermediate layer beyond the non-skin side layer in the longitudinal direction, excretory fluid can be effectively migrated along the entire longitudinal direction of the non-skin side layer.

[0041] (Aspect 17) An absorbent article described in any of aspects 1 to 16, wherein at least one of the skin-side layer and the non-skin-side layer has a plurality of point-like compression portions formed to compress the absorbent core in a point-like manner in the thickness direction.

[0042] According to the seventeenth aspect, the compressed points reduce the amount of clumps of the superabsorbent polymer, suppressing the gritty feel. Furthermore, by compressing locally, the absorbent body is prevented from collapsing without losing its flexibility.

[0043] (Aspect 18) An absorbent article described in any of aspects 1 to 17, wherein a core wrap sheet is arranged on the skin side of the skin side layer in the thickness direction, a strip-shaped adhesive is provided on the non-skin side surface of the core wrap sheet in the thickness direction, the average width of the strip-shaped adhesive is smaller than the average particle size of the superabsorbent polymer, and the minimum value of the distance between the intersections of the strip-shaped adhesive is smaller than the average particle size of the superabsorbent polymer when maximally swollen.

[0044] According to the eighteenth aspect, when the SAP absorbs water (maximum swelling), the SAP particles are less likely to protrude from the mesh formed by the intersection of the numerous strip-shaped adhesives, and the movement of the SAP is suppressed. As a result, even after the SAP particles swell, clumps of SAP are less likely to form, and the gritty feel can be reduced.

[0045] (Aspect 19) An absorbent article having an absorbent core which, in an unfolded state, has a longitudinal direction, a width direction, and a thickness direction which are perpendicular to each other and which contains a superabsorbent polymer, and a sheet material (core wrap sheet or nonwoven fabric) arranged on one side of the absorbent core in the thickness direction, wherein a strip of adhesive is provided on the other side of the sheet material in the thickness direction, and the average width of the strip of adhesive is smaller than the average particle size of the superabsorbent polymer, and when the area of the other side of the sheet material which is located outside the outermost end of the absorbent core in the width direction is defined as an outer region, and the area of the other side of the sheet material which is located inside the outermost end of the absorbent core in the width direction is defined as an inner region, the number of intersections of the strip of adhesive per unit area in the outer region is smaller than the number of intersections of the strip of adhesive per unit area in the inner region.

[0046] In the absorbent article of aspect 19, because a strip of adhesive is applied with a width narrower than the SAP particle diameter, the adhesive easily penetrates into the gaps between the SAP particles, fixing the SAP particles together and preventing deformation. Also, in the outer widthwise regions of the sheet material where no SAP particles are disposed, the adhesive application density is reduced so that the number of intersections between adhesives is fewer than in the inner widthwise region where the SAP particles are disposed, thereby preventing adhesive from seeping out.

[0047] (Aspect 20) Aspect 19 is an absorbent article according to aspect 19, wherein the minimum distance between intersections of the strip-shaped adhesives is smaller than the average particle size of the superabsorbent polymer when swollen.

[0048] According to the absorbent article of aspect 20, even when the SAP particles swell upon absorbing excrement during use, the SAP particles are less likely to protrude from the mesh of the strip-shaped adhesive, which makes the absorbent core (non-skin side layer) less likely to collapse.

[0049] (Aspect 21) 21. The absorbent article of claim 19 or 20, wherein the minimum distance between intersections of the strips of adhesive is smaller than the average particle size of the superabsorbent polymer when not swollen.

[0050] According to the absorbent article of aspect 21, even before use, SAP particles are less likely to leak out of the mesh formed by the intersection of the numerous strip-shaped adhesives. For example, this prevents the SAP from shifting position during distribution of the absorbent article, which can cause the absorbent core to collapse before use.

[0051] (Aspect 22) Aspect 22 is the absorbent article according to any one of aspects 19 to 21, wherein the thickness of the absorbent core is greater than 1.5 times the average particle size of the superabsorbent polymer.

[0052] According to the absorbent article of aspect 22, the absorbent core has at least 1.5 layers of SAP particles stacked therein, thereby improving water absorption and water retention compared to a single-layer absorbent core in which the SAP particles are arranged in a plane.

[0053] (Aspect 23) 23. The absorbent article according to any one of aspects 19 to 22, wherein at least a portion of the strip-shaped adhesive is present at a central position in the thickness direction of the absorbent core.

[0054] According to the absorbent article of aspect 23, the adhesive penetrates into the absorbent core, so that the SAP particles are less likely to become displaced from one another, and the absorbent core is less likely to collapse.

[0055] (Aspect 24) Aspects 19 to 23 are an absorbent article according to any one of aspects 19 to 23, wherein the adhesive for fixing the superabsorbent polymer to the sheet material has a residual stress of 2 KPa or more and 20 KPa or less.

[0056] In the absorbent article of aspect 24, the adhesive that fixes the SAP particles has a resistance (residual stress) that is sufficient to prevent the SAP particles from falling off the sheet material (base sheet) even when an external force is applied, thereby increasing the probability that the fixation rate of the SAP particles will be 40% or more, and making the absorbent core less likely to collapse.

[0057] (Aspect 25) An absorbent article described in any of aspects 19 to 24, having an intermediate sheet on the other side of the absorbent core in the thickness direction, a strip of adhesive on one side of the intermediate sheet in the thickness direction, and the average width of the strip of adhesive on the other side of the sheet material being smaller than the average width of the strip of adhesive on the one side of the intermediate sheet.

[0058] In the absorbent article of aspect 25, the adhesive is not applied excessively to the skin-side (other side) surface of the sheet material, which prevents the adhesive from seeping out to the non-skin-side surface of the sheet material. On the other hand, if a larger amount of adhesive is applied to the non-skin-side (one side) surface of the intermediate sheet, a larger amount of adhesive is ejected toward the SAP particles, which more firmly bonds the SAP particles together and prevents the absorbent core from losing its shape.

[0059] (Aspect 26) An absorbent article described in any of aspects 19 to 24, having an intermediate sheet on the other side of the absorbent core in the thickness direction, a strip of adhesive on one side of the intermediate sheet in the thickness direction, and the average width of the strip of adhesive on the other side of the sheet material being larger than the average width of the strip of adhesive on the one side of the intermediate sheet.

[0060] In the absorbent article of aspect 26, the amount of adhesive applied to the intermediate sheet is reduced, which makes it less likely that excreted liquid will be hindered from moving in the thickness direction of the intermediate sheet, thereby facilitating smooth transfer of excreted liquid and the like to the absorbent core provided on the non-skin side (one side) of the intermediate sheet in the thickness direction.

[0061] (Aspect 27) Aspects 19 to 26: The absorbent article according to any one of aspects 19 to 26, wherein the absorbent core has a low basis weight region that is a region having a predetermined width in the width direction and has a basis weight lower than that of surrounding areas.

[0062] According to the absorbent article of aspect 27, excrement is absorbed less easily in the low basis weight region than in other regions, and excrement is more likely to spread along the low basis weight region. Therefore, even if a force that compresses the absorbent core in the thickness direction is applied, for example, when the wearer assumes a sitting position while wearing the absorbent article, excrement can be easily drawn into the absorbent core.

[0063] (Aspect 28) The absorbent article according to any one of aspects 19 to 27, wherein the average basis weight of the low basis weight region is greater than 0% and not more than 50% of the average basis weight of the region of the absorbent core other than the low basis weight region.

[0064] According to the absorbent article of aspect 28, by setting the average basis weight in the low basis weight region to 50% or less of the average basis weight of the other regions, the difference in average basis weight becomes larger than when the average basis weight is greater than 50%, making it easier to move liquids such as excrement along the low basis weight region. Furthermore, if the average basis weight in the low basis weight region is greater than 0%, at least the entire low basis weight region is prevented from being configured as a slit, and the strength of the low basis weight region is more easily ensured.

[0065] (Aspect 29) In the absorbent article according to any one of aspects 19 to 28, the minimum distance between the intersections of the strip-shaped adhesives is smaller than the width of the low basis weight region.

[0066] According to the absorbent article of the twenty-ninth aspect, at least one intersection of adhesives is provided between both side edges of the low basis weight region, which facilitates fixation of SAP particles in the low basis weight region, and also increases the likelihood of adhesive being present at both side edges of the low basis weight region. This prevents the low basis weight region of the absorbent core from collapsing or being crushed.

[0067] (Aspect 30) An absorbent article described in any of aspects 19 to 29, having an intermediate sheet on the other side of the absorbent core in the thickness direction, and having a portion in the low basis weight region where the sheet material and the intermediate sheet are joined in the thickness direction.

[0068] In the absorbent article of Aspect 30, if the sheet material and the intermediate sheet are joined at least partially in the area where the low basis weight region is provided, the SAP particles are prevented from migrating across the low basis weight region. That is, each of the absorbent cores divided by the low basis weight region is more likely to independently maintain its shape. Therefore, the absorbent core as a whole is less likely to lose its shape.

[0069] (Aspect 31) An absorbent article according to any one of aspects 19 to 30, comprising an absorbent body having the absorbent core and the sheet material, and having intermittent regions at the front and rear ends of the absorbent body in the longitudinal direction where the superabsorbent polymer is not provided.

[0070] In the absorbent article of aspect 31, SAP particles are not disposed in the intermittent regions, which makes it easier for the sheet material to be directly bonded to a member (e.g., an intermediate sheet) disposed opposite the sheet material in the thickness direction, which makes it difficult for the SAP particles constituting the absorbent core to protrude to both ends in the front-rear direction, and therefore the absorbent core is less likely to lose its shape.

[0071] (Aspect 32) An absorbent article described in any of aspects 19 to 31, wherein the average basis weight of the superabsorbent polymer in front of the center position in the longitudinal direction of the absorbent body is smaller than the average basis weight of the superabsorbent polymer in back of the center position in the longitudinal direction of the absorbent body.

[0072] According to the absorbent article of aspect 32, by increasing the average basis weight of the SAP particles in the front longitudinal region located near the wearer's excretory opening when worn, excretory fluids such as urine can be more quickly absorbed, thereby suppressing urine leakage on the abdominal side.

[0073] (Aspect 33) An absorbent article described in any of aspects 19 to 31, wherein the average basis weight of the superabsorbent polymer in front of the center position in the longitudinal direction of the absorbent body is equal to or greater than the average basis weight of the superabsorbent polymer in back of the center position in the longitudinal direction of the absorbent body.

[0074] According to the absorbent article of aspect 33, when worn, by increasing the average basis weight of the SAP particles in the rear longitudinal region located on the back side (buttocks side) of the wearer, excretory fluids such as urine can be prevented from flowing around the buttocks to the back side and leaking out from the upper end of the back side.

[0075] (Aspect 34) This is an absorbent article described in any of aspects 19 to 33, in which a second absorbent layer (skin side layer) containing the superabsorbent polymer and liquid-absorbent fibers is laminated to the absorbent core (non-skin side layer) in the thickness direction.

[0076] According to the absorbent article of aspect 34, the absorbent core has a laminated structure of two or more layers (a non-skin-side layer and a skin-side layer), which improves water absorption and water retention capacity compared to an absorbent core with only one layer.

[0077] (Aspect 35) In the absorbent article according to any one of aspects 19 to 33, the second absorbent layer (skin side layer) is disposed on the other side of the absorbent core (non-skin side layer).

[0078] According to the absorbent article of aspect 35, the second absorbent layer (skin-side layer) containing liquid-absorbent fibers that absorb water faster than the SAP particles is disposed on the skin-side (other side) in the thickness direction, so that excreted liquid is quickly drawn from the skin-side to the non-skin-side and is easily retained in the non-skin-side layer disposed on the non-skin-side. This improves the dryness on the skin-side side, making it less likely for the wearer to experience discomfort or annoyance.

[0079] (Aspect 36) The absorbent article according to any one of aspects 19 to 34, wherein the second absorbent layer (skin side layer) is disposed on the one side of the absorbent core (non-skin side layer).

[0080] According to the absorbent article of aspect 36, the absorbent core (skin-side layer) containing SAP particles, which have higher water retention than liquid-absorbent fibers, is disposed on the non-skin side (one side) in the thickness direction, thereby increasing water retention on the skin side and making rewet less likely to occur, thereby making it less likely for the wearer to experience discomfort or an unpleasant feeling.

[0081] (Aspect 37) Aspects 19 to 36: The absorbent article according to any one of aspects 19 to 36, wherein the sheet material is made of nonwoven fabric.

[0082] According to the absorbent article of Aspect 37, when the nonwoven fabric base sheet is conveyed in the MD while being coated with adhesive or laminated with SAP particles, the nonwoven fabric base sheet is resistant to tearing, making it possible to form an absorbent body (absorbent core) with a stable shape. Furthermore, if the base sheet is conveyed while being sucked by a suction mechanism or the like, the SAP particles can be easily fixed on the base sheet.

[0083] (Aspect 38) An absorbent article according to any one of aspects 1 to 37, comprising an absorbent body, the absorbent body having an absorbent core with a skin-side layer, an intermediate layer, and a non-skin-side layer laminated at least in the thickness direction, the intermediate layer not including a nonwoven fabric.

[0084] According to the 38th aspect, the skin-side layer and the intermediate layer of the absorbent core are laminated adjacently in the thickness direction without a nonwoven fabric in between, which prevents the adhesive or the nonwoven fabric from interfering with the transfer of excreted fluid from the skin-side layer to the intermediate layer, thereby increasing the rate of absorption by the intermediate layer.

[0085] (Aspect 39) Aspect 39 is the absorbent article according to any one of Aspects 1 to 38, wherein the layer of the absorbent core closest to the skin does not contain a water-absorbent resin powder.

[0086] According to aspect 39, since the layer closest to the skin does not contain water-absorbent resin powder such as SAP, it is less likely to give a granular, gritty feeling to the wearer's skin, reducing the discomfort felt when worn.

[0087] (Aspect 40) 40. The absorbent article according to any one of aspects 1 to 39, wherein the superabsorbent polymer in the layer closest to the skin of the absorbent core has a liquid permeation rate under load of more than 10 seconds.

[0088] According to aspect 40, by making the liquid permeation rate under load in the layer closest to the skin exceed 10 seconds, the water retention of the absorbent core is improved compared to the opposite case, leading to prevention of leakage and also preventing the absorbent core from becoming thicker locally.

[0089] === Implementation form === The absorbent article according to the present invention will be described taking as an example a pants-type disposable diaper 1 for infants (hereinafter also referred to as "diaper 1"). However, the absorbent article according to the present invention also includes tape-type disposable diapers, shorts-type napkins, absorbent pads, sanitary napkins, and other absorbent articles. Furthermore, the wearer of the absorbent article is not limited to infants, but may also be an adult or a living organism such as an animal.

[0090] <Diaper 1 composition> FIG. 1 is a schematic perspective view of a diaper 1. FIG. 2 is a plan view of the diaper 1 in an unfolded and stretched state, as seen from the skin side. FIG. 3 is a schematic cross-sectional view taken along the center line CL in FIG. 2. The "stretched state" of the diaper 1 refers to a state in which the entire diaper 1 is stretched without wrinkles, specifically, a state in which the dimensions of each component constituting the diaper 1 (e.g., the absorbent main body 10 and waist-lined sections 30 and 40, which will be described later) are stretched to the same dimensions as or close to the dimensions of each component alone. The "unfolded state" of the diaper 1 refers to a state in which the pair of side joining sections 2 provided on both sides of the diaper 1 are separated, and the diaper 1 is opened and unfolded in a flat plane.

[0091] The diaper 1 has a vertical direction, a width direction, and a front-to-rear direction that are perpendicular to each other, and has a waist opening BH and a pair of leg openings LH. The upper side in the vertical direction corresponds to the waist opening BH side, and the lower side corresponds to the crotch side. The front side in the front-to-rear direction corresponds to the wearer's abdomen side, and the rear side corresponds to the wearer's back side. The width direction is a direction along the stretch direction of the elastic threads 33, 43 of the front waist portion 30 and the rear waist portion 40. The vertical direction is a direction perpendicular to the stretch direction.

[0092] The diaper 1 is a so-called three-piece pants-type diaper having a liquid-absorbent main body 10 and a pair of waist-surrounding sections 30, 40. Of the pair of waist-surrounding sections, the one covering the wearer's abdominal region is also referred to as the front waist-surrounding section 30, and the one covering the wearer's dorsal region is also referred to as the rear waist-surrounding section 40.

[0093] In the unfolded state shown in Fig. 2, the diaper 1 has a longitudinal direction, a width direction, and a thickness direction, which are perpendicular to one another. The longitudinal direction is along the longitudinal direction of the absorbent main body 10 and along the vertical direction of the pants-type diaper 1. The thickness direction is the direction in which the materials constituting the diaper 1 are layered, as shown in Fig. 3. In the thickness direction, the side that contacts the wearer's skin is referred to as the skin side, and the opposite side is referred to as the non-skin side. In the unfolded state, the front waistband 30 and the rear waistband 40 are aligned parallel to each other with a gap in the longitudinal direction, with the absorbent main body 10 spanning between them, with each longitudinal end of the absorbent main body 10 joined and fixed to the skin side of the nearest waistband 30, 40, resulting in a generally H-shaped external shape in a plan view. From this state, the absorbent main body 10 is folded in half along the longitudinal center line CL. In this folded state, the opposing front waistline portion 30 and rear waistline portion 40 are joined and connected at their widthwise opposite sides to form a pair of side joint portions 2. The side joint portions 2 are formed by known joining means such as welding or adhesive.

[0094] The absorbent main body 10 has an absorbent body 20 (details will be described later), a liquid-permeable top sheet 12 arranged closer to the skin than the absorbent body 20, and a back sheet 13 arranged closer to the skin than the absorbent body 20. The back sheet 13 has a two-layer structure consisting of a liquid-impermeable sheet 13a and a hydrophobic outer sheet 13b arranged on the far side of the liquid-impermeable sheet 13a. However, the absorbent main body 10 may also include sheet members other than these. For example, a second sheet (not shown) may be provided between the top sheet 12 and the absorbent body 20 in the thickness direction.

[0095] A pair of leakage preventing walls 15 is provided along the longitudinal direction of the absorbent main body 10 on both widthwise sides of the absorbent main body 10. In Fig. 3, a part of the exterior sheet 13b extends outward beyond both ends of the absorber 20 in the widthwise direction and is folded toward the skin at multiple locations to form the pair of leakage preventing walls 15. A leakage preventing wall elastic member 16 such as rubber thread is attached to the tip of the leakage preventing wall 15 in a state stretched along the longitudinal direction of the absorbent main body 10, so that the leakage preventing wall 15 can stand up toward the skin. In addition, leg-hole elastic members 17 such as rubber thread are attached to both widthwise sides of the absorbent main body 10 in a state stretched along the longitudinal direction of the absorbent main body 10.

[0096] The front waistline section 30 and the rear waistline section 40 each have a skin-side sheet 31, 41, a non-skin-side sheet 32, 42, and multiple waistline elastic members 33, 43 such as rubber threads. The multiple waistline elastic members 33, 43 are arranged vertically between the skin-side sheet 31, 41 and the non-skin-side sheet 32, 42 and are attached in a stretched state in the width direction. The stretchability of the waistline elastic members 33, 43 allows the front waistline section 30 and the rear waistline section 40 to fit the wearer's waist. In addition, cover sheets 34, 44 may be provided to cover the upper end of the absorbent main body 10 from the skin side. The cover sheets 34, 44 can prevent the absorbent main body 10 from opening.

[0097] 2, the front waistline portion 30 and the rear waistline portion 40 have different planar shapes in the unfolded and stretched state. The front waistline portion 30 has a vertical length that is roughly the same as that of the side joint portion 2 and a rectangular shape that is long in the width direction. The rear waistline portion 40 has a rectangular portion that overlaps with the front waistline portion 30 and a generally trapezoidal portion 40E that extends downward from the rectangular portion 30. The extending portion 40E can cover the wearer's buttocks.

[0098] The basic configuration of the diaper 1 has been described above, but the above configuration is merely an example and is not intended to be limiting. For example, the front waistline portion 30 and the rear waistline portion 40 may be formed from a single continuous member, or an outer member may be provided in the crotch area connecting the front waistline portion 30 and the rear waistline portion 40. Furthermore, the elastic members such as the waistline elastic members 33, 43 may be sheet-like elastic members instead of rubber threads.

[0099] ===About absorbent body 20=== Fig. 4 is a cross-sectional schematic diagram of the absorbent body 20 of this embodiment. Fig. 5 is a plan view of the absorbent cores 21 to 23 superimposed on each other. Fig. 6A is a plan view of the skin side layer 21 and the intermediate layer 22, and Fig. 6B is a plan view of the non-skin side layer 23.

[0100] As shown in FIG. 4, the absorbent body 20 has absorbent cores 21-23 between a core wrap sheet 25 on the skin side and a core wrap sheet 26 on the non-skin side. The absorbent cores 21-23 are components that absorb and retain excretory fluids such as urine, and include a liquid-absorbent fiber 201 and a super absorbent polymer. The liquid-absorbent fiber 201 and the super absorbent polymer (hereinafter also referred to as SAP) are not particularly limited as long as they can be used as the absorbent core of an absorbent article. For example, the liquid-absorbent fiber 201 can be wood pulp fiber, non-wood pulp fiber such as bagasse, kenaf, bamboo, hemp, or cotton, regenerated cellulose fiber such as rayon fiber, or semi-synthetic fiber such as acetate fiber. Examples of SAP include starch-based, cellulose-based, and synthetic polymer-based polymer absorbents. The core wrap sheets 25 and 26 are liquid-permeable sheet materials, such as tissue and nonwoven fabric.

[0101] The absorbent cores 21-23 each include a skin-side layer 21, an intermediate layer 22, and a non-skin-side layer 23. The intermediate layer 22 is located closer to the skin than the skin-side layer 21 in the thickness direction, and the non-skin-side layer 23 is located closer to the skin than the intermediate layer 22 in the thickness direction. The skin-side layer 21 has a first thickness t1, and is a layer in which the volume occupied by SAPs is larger than the volume occupied by the liquid-absorbent fibers 201. The intermediate layer 22 has a second thickness t2, and is a layer in which the volume occupied by the liquid-absorbent fibers 201 is larger than the volume occupied by the SAPs. The non-skin-side layer 23 has a third thickness t3, and is a layer in which the volume occupied by SAPs is larger than the volume occupied by the liquid-absorbent fibers 201.

[0102] The absorbent body 20 of this embodiment further includes a skin-side upper layer 24, which has a fourth thickness t4 that is thinner than the first thickness t1 of the skin-side layer 21, and is located closer to the skin in the thickness direction than the skin-side layer 21. The skin-side upper layer 24 is a layer in which the volume occupied by the liquid-absorbent fiber 201 is greater than the volume occupied by the SAP. Specifically, the skin-side upper layer 24 of this embodiment is composed only of the liquid-absorbent fiber 201. That is, the skin-side upper layer 24, which is the layer closest to the skin among the multiple layers constituting the absorbent core, does not contain water-absorbent resin powder such as superabsorbent polymer (SAP). The absence of water-absorbent resin powder such as SAP in the layer closest to the skin makes it less likely to give a granular, gritty feel to the wearer's skin, reducing discomfort during wear. However, the skin-side upper layer 24 is not necessarily provided in the absorbent body 20 of this embodiment.

[0103] 4, in this embodiment, the skin side layer 21 and the intermediate layer 22 are integrally formed, and therefore the volume occupancy of SAP decreases and the volume occupancy of liquid-absorbent fiber 201 increases from the skin side layer 21 toward the intermediate layer 22. Such an absorbent core can be manufactured, for example, by adjusting the order, amount, timing, etc. of feeding the SAP and liquid-absorbent fiber 201 into a forming mold (recess) that corresponds to the shape of the absorbent core and is provided on the outer circumferential surface of a rotating drum.

[0104] In this embodiment, the skin side layer 21 and the intermediate layer 22 are laminated integrally, i.e., adjacent to each other in the thickness direction, without any adhesive or nonwoven fabric in between. This prevents the adhesive or nonwoven fabric from interfering with the transfer of excreted fluid from the skin side layer 21 to the intermediate layer 22, and increases the rate of absorption by the intermediate layer 22.

[0105] Furthermore, in this embodiment, the non-skin side layer 23 is not formed integrally with the intermediate layer 22, but is laminated adjacent to the intermediate layer 22 in the thickness direction via the non-woven fabric 27. The presence of the non-woven fabric 27 allows the excreted liquid to diffuse in the planar direction on the non-woven fabric 27 before transferring from the intermediate layer 22 to the non-skin side layer 23. Therefore, the excreted liquid diffused in the planar direction can transfer to the non-skin side layer 23, and the absorbent cores 21-23 can be effectively utilized in the planar direction.

[0106] The method for comparing the volumes occupied by the liquid absorbent fiber 201 and SAP in each of the skin side layer 21, the intermediate layer 22, the non-skin side layer 23, and the skin side upper layer 24 will be described later.

[0107] In the case of an absorbent core containing SAP, as in this embodiment, if the ratio of liquid-absorbent fibers in the absorbent core is reduced and the SAP ratio is increased in order to further improve absorbency, the SAP may feel gritty when touching the diaper, and the SAP layer may be more likely to break down due to reduced entanglement with the liquid-absorbent fibers. However, on the other hand, if the SAP ratio is reduced to suppress the gritty feel of the SAP, it becomes difficult to ensure absorbency. Therefore, it is necessary to ensure absorbency while reducing the uncomfortable gritty feel of the SAP.

[0108] The absorbent body 20 of this embodiment has an absorbent core comprising a skin-side layer 21, an intermediate layer 22, a non-skin-side layer 23, and an upper skin-side layer 24. However, the total water retention capacity of the SAP present in the skin-side layer 21 is different from the total water retention capacity of the SAP present in the non-skin-side layer 23. Specifically, the total water retention capacity of the SAP present in the non-skin-side layer 23 is greater than the total water retention capacity of the SAP present in the skin-side layer 21. The skin-side layer 21, which has a lower total water retention capacity, can prevent SAP from swelling and inhibiting liquid absorption, allowing excreted liquid to diffuse easily. The excreted liquid that is quickly absorbed and diffused in the skin-side layer 21 quickly penetrates into the intermediate layer 22. Furthermore, since the intermediate layer 22 has a high volume occupancy rate of the liquid-absorbent fiber 201, the excreted liquid is temporarily stored in the intermediate layer 22 and then transferred to the layer with a higher total water retention capacity, i.e., the non-skin-side layer 23, which is the layer that ultimately retains water. Furthermore, since the skin-side layer 21 has a small total water retention capacity, the total volume of SAP after absorbing water is small, and therefore the wearer is less likely to feel uncomfortable with the gritty feel of SAP. Therefore, the non-skin-side layer 23, which has a large total water retention capacity, ensures absorbency, while reducing the uncomfortable feel even after the absorbent cores 21-24 have absorbed excrement.

[0109] Furthermore, although the skin-side layer 21 has a smaller total water retention capacity than the non-skin-side layer 23, it has a high volume occupancy rate of SAP and therefore has adequate water retention. Therefore, when excreted fluid from the intermediate layer 22 or the non-skin-side layer 23 attempts to return to the skin side, the SAP of the skin-side layer 21 absorbs and retains the excreted fluid, preventing the excreted fluid from rewetting.

[0110] The total water retention capacity of SAP present in the skin-side layer 21 and the non-skin-side layer 23 can be measured by the following measurement method. First, 0.9% saline solution (enough to fully immerse the sample) is prepared in a water bath. Next, a test piece is prepared. The test pieces are cut into 50 mm pieces in the longitudinal direction of one absorbent body 20. When the absorbent body 20 is cut into 50 mm pieces, the length of the last test piece in the longitudinal direction does not have to be less than 50 mm. First, in order to measure the total water retention capacity of the SAP present in the skin side layer 21, each test piece is separated as follows. (Layer separation method 1) 1) Peel off the core wrap sheet 26 from the non-skin side. 2) Peel off the non-skin side layer 23 3) Peel off the nonwoven fabric 27 4) Peel off the layer of liquid absorbent fiber 201 (corresponding to the intermediate layer 22) of the remaining sheet. 5) The sum of 1) to 4) above is X1. 6) The part other than X1 is designated as X2 (X2 essentially includes the skin side layer 21, the skin side upper layer 24, and the core wrap sheet 25). As the next test piece, an absorbent body 20 different from the one absorbent body described above is prepared and similarly cut into 50 mm pieces in the longitudinal direction. To measure the total water retention capacity of the SAP present in the non-skin side layer 23, each cut test piece is separated as follows. (Layer separation method 2) 1) Peel off the core wrap sheet 25 from the skin side. 2) Of the remaining sheet, the layer of liquid absorbent fiber 201 (corresponding to the middle layer 22) is not peeled off (this results in peeling off the skin-side upper layer 24, the skin-side layer 21, and the middle layer 22). 3) Peel off the nonwoven fabric 27 4) The above 1) to 3) are X4 5) The portion other than X4 is designated as X3 (X3 essentially includes the non-skin side layer 23 and the core wrap sheet 26).

[0111] Next, samples X1 to X4 are each placed in a mesh plastic bag, sealed, and their weight (A) before water absorption is measured. After measurement, each sample X1 to X4 is immersed in saline for 30 minutes. After 30 minutes, each sample is removed from the water bath, and with the core wrap sheet side of each sample facing downwards, an acrylic plate (320 x 545 mm, 3 to 5 mm thick, weighing 400 to 600 g) and a 5 kg weight are placed on top, and left for 20 minutes. After 20 minutes, the weight and acrylic plate are removed, and the weight (B) of each sample is measured. Weight (B) - Weight (A) is the amount of water absorbed.

[0112] After weight measurement, each sample was dehydrated using a centrifuge at 75G for 90 seconds. After dehydration, the weight (C) of each removed sample was measured. Weight (C) minus weight (A) is the water retention capacity. Note that dehydration using a centrifuge removes water adhering to the liquid absorbent fiber 201, core wrap sheet, and nonwoven fabric, and only the amount of water chemically retained by the SAP is determined. Therefore, the water retention capacity calculated by "weight (C) minus weight (A)" is the water retention capacity of the SAP present in each sample. Therefore, the water retention capacity of sample X2 is the water retention capacity of the SAP present in the skin-side layer 21, and the water retention capacity of sample X3 is the water retention capacity of the SAP present in the non-skin-side layer 23. In this embodiment, in order to compare the "total water retention capacity" of SAP present in the skin-side layer 21 with the "total water retention capacity" of SAP present in the non-skin-side layer 23, measurements were carried out on each test piece cut into 50 mm pieces as described above, and the sum of the water retention capacity of X2 of each test piece is the "total water retention capacity of SAP present in the skin-side layer 21," and the sum of the water retention capacity of X3 of each test piece is the "total water retention capacity of SAP present in the non-skin-side layer 23."

[0113] As an example, the water retention capacity of the above-mentioned X2 (one sample) was 25.4 g, and the water retention capacity of the above-mentioned X3 (one sample) was 41.1 g. In other words, when comparing the water retention capacities of test pieces with a longitudinal length of 50 mm, the water retention capacity of the SAP present in the non-skinside layer 23 was clearly greater. Therefore, it can be seen that in the diaper 1 of this embodiment, the total water retention capacity of the SAP present in the non-skinside layer 23 is greater than the total water retention capacity of the SAP present in the skinside layer 21.

[0114] Furthermore, the comparison of the volumes occupied by the liquid absorbent fiber 201 and SAP in each of the skin side layer 21, the intermediate layer 22, the non-skin side layer 23, and the skin side upper layer 24 can be confirmed by the following method. For example, with the diaper 1 in a natural, dry state without any external force acting on it, the diaper 1 (absorbent body 20) is cut widthwise at any position in the longitudinal direction of the absorbent body 20, specifically at a position where the four layers 21 to 24 are stacked and away from the product folding position. Next, the cut surface is magnified (e.g., 30 to 100 times) and photographed using an optical microscope (e.g., Keyence Digital Microscope VHX-7000 or equivalent). In the photographed cross-sectional image, the liquid-absorbent fibers 201 and SAP are identified. Then, in the cross-sectional image, it is confirmed that the following are layered in order from the skin side in the thickness direction: a skin-side upper layer 24 in which the area occupied by the liquid-absorbent fibers 201 is larger than that of the SAP; a skin-side layer 21 in which the area occupied by the SAP is larger than that of the liquid-absorbent fibers 201; an intermediate layer 22 in which the area occupied by the liquid-absorbent fibers 201 is larger than that of the SAP; and a non-skin-side layer 23 in which the area occupied by the SAP is larger than that of the liquid-absorbent fibers 201. If the above is confirmed, the four layers 21 to 24 of this embodiment are identified. Cross-sectional images are prepared at multiple locations (e.g., 10 locations) along the longitudinal direction of the absorbent body 20 in which such four layers 21 to 24 can be confirmed, and if the area occupied by the SAP is larger than the area occupied by the liquid-absorbent fibers 201 in all of the cross-sectional images, then that layer is a layer in which "the volume occupied by the SAP is larger than the volume occupied by the liquid-absorbent fibers," and if the area occupied by the liquid-absorbent fibers 201 is larger than the area occupied by the SAP in all of the cross-sectional images, then that layer is a layer in which "the volume occupied by the liquid-absorbent fibers is larger than the volume occupied by the SAP."

[0115] In addition, a comparison of the volumes occupied by the liquid-absorbent fibers 201 and SAP in each layer can be made by visualizing the liquid-absorbent fibers 201 and SAP using X-ray microtomography (X-ray CT), for example, by the method described below: Science Direct, Carbohydrate Polymers 254, Mathias A. Hobisch et al., February 15, 2021, "How cellulose nanofibrils and cellulose microparticles impact paper strength—A visualization approach", Section "3.6. X-ray microtomography", https: / / www.sciencedirect.com / science / article / pii / S0144861720315794.

[0116] In this embodiment, the average total area occupied by SAPs per unit area in a cross section taken along the thickness direction of the skin-side layer 21 is different from the average total area occupied by SAPs per unit area in a cross section taken along the thickness direction of the non-skin-side layer 23. Specifically, the average total area occupied by SAPs per unit area in a cross section taken along the thickness direction of the non-skin-side layer 23 is greater than the average total area occupied by SAPs per unit area in a cross section taken along the thickness direction of the skin-side layer 21. A layer with a small average total area occupied by SAPs per unit area is less likely to feel gritty when touched. By using such a layer as the skin-side layer 21, the wearer is less likely to feel an uncomfortable sensation from the SAPs. Furthermore, a skin-side layer 21 with a small average total area occupied by SAPs per unit area can prevent SAPs from swelling and inhibiting absorption, thereby improving the diffusibility of excretory fluids. A layer with a large average value of the total area occupied by SAP per unit area has improved absorbency, and such a layer, the non-skin side layer 23, can absorb and retain a larger amount of excreted liquid even in the case of repeated excretion, thereby suppressing rewetting.

[0117] Furthermore, a skin-side upper layer 24 is provided closer to the skin than the skin-side layer 21 in the thickness direction. The skin-side upper layer 24 has a fourth thickness t4 that is thinner than the first thickness t1 of the skin-side layer 21 and the volume occupied by the liquid-absorbent fibers 201 is larger than the volume occupied by the SAP. Since the skin-side upper layer 24, which has a high volume occupancy rate of the liquid-absorbent fibers 201, is located closer to the skin than the skin-side layer 21, the wearer's perception of the unevenness of the SAP can be further reduced. Furthermore, because the skin-side upper layer 24 is a layer with a high content of the liquid-absorbent fibers 201, it improves the ability to draw excreted liquid from sheets (such as a top sheet) placed closer to the skin. Furthermore, the liquid-absorbent fibers 201 contained in the skin-side upper layer 24 make it difficult for the SAP of the skin-side layer 21 to roll within the layer, preventing a deterioration in the tactile feel. The skin-side upper layer 24 is positioned closer to the skin than the skin-side layer 21, but is thinner than the first thickness t1 of the skin-side layer 21, so it can absorb excreted liquid without excessively retaining the excreted liquid, thereby reducing rewetting.

[0118] The "average value of the total area occupied by SAPs per unit area in a cross section taken along the thickness direction of the skin-side layer 21 (non-skin-side layer 23)" can be determined, for example, using the volume comparison method described above, as follows: The absorbent body 20 is cut at 10 locations along the width direction at any position in the longitudinal direction of the absorbent body 20, specifically, at a location where the skin-side layer 21 and the non-skin-side layer 23 are laminated and away from the product folding position. The cut surfaces are photographed under magnification using the optical microscope, and the "total area occupied by SAPs per unit area" of the skin-side layer 21 and the "total area occupied by SAPs per unit area" of the non-skin-side layer 23 are determined for each of the cut surfaces, and their average value is defined as the "average value of the total area occupied by SAPs per unit area."

[0119] As described above, the skin-side layer 21 has a first thickness t1, the intermediate layer 22 has a second thickness t2, and the non-skin-side layer 23 has a third thickness t3 (see FIG. 4 ). The first thickness t1 to the third thickness t3 refer to average thicknesses. In this embodiment, the third thickness t3 of the non-skin-side layer 23 is thicker than the first thickness t1 of the skin-side layer 21. Specifically, the third thickness t3 of the non-skin-side layer 23 is preferably 0.38 mm to 0.58 mm for the S-size diaper 1 and preferably 0.58 mm to 0.69 mm for the XXL-size diaper 1. The first thickness t1 of the skin-side layer 21 is preferably 0.3 mm to 0.48 mm for the S-size diaper 1 and preferably 0.45 mm to 0.65 mm for the XXL-size diaper 1. The skin-side layer 21, which is thinner than the non-skin-side layer 23, also becomes thinner after moisture retention. That is, even after water retention, SAP swelling is unlikely to cause absorption inhibition, and the feel (gritty feeling) of the skin side of the diaper 1 is unlikely to deteriorate. The average thickness of the absorbent body 20 is preferably 2.0 to 2.5 mm.

[0120] The average thickness t2 of the intermediate layer 22 is preferably 0.5 mm or more. More preferably, it is 0.9 mm to 1.1 mm for an S-size diaper 1 and 1.28 mm to 1.61 mm for an XXL-size diaper 1. This allows for more excreted liquid to be absorbed between the fibers of the liquid-absorbent fibers 201 of the intermediate layer 22 than when the average thickness of the intermediate layer 22 is less than 0.5 mm, for example, compared to when the intermediate layer 22 is a nonwoven fabric (sheet member) formed of pulp fibers or the like. Therefore, the excreted liquid can be quickly and temporarily absorbed in the intermediate layer 22, and after diffusing in the intermediate layer 22, the excreted liquid is quickly transferred to the non-skin-side layer 23, ensuring absorbency. However, if the intermediate layer 22 is too thick, it may feel bulky, so the average thickness (second thickness t2) of the intermediate layer 22 is preferably 2.5 mm or less.

[0121] The thicknesses (t1 to t3) of the layers 21 to 23 can be measured using a known method. For example, with the diaper 1 in a natural, dry state without any external force, the diaper 1 (absorbent body 20) is cut widthwise at any longitudinal position in the portion of the diaper 1 where the absorbent body 20 is located, specifically, at a location where the three layers 21 to 23 are stacked and away from the product folding position. To prevent damage to the components of the absorbent body 20, the diaper 1 is cut at a predetermined location and measured. Next, using an optical microscope (e.g., Keyence Digital Microscope VHX-7000 or equivalent), the cut surface is placed upright and magnified (e.g., 30 to 100 times) and photographed. The focus of the magnified photograph is on the liquid-absorbent fiber 201. In the captured cross-sectional image, the layer in which the liquid-absorbent fiber 201 is visible is determined to be the intermediate layer 22, and the portions of the absorbent core closer to the skin or closer to the skin are determined to be the skin-side layer 21 and the non-skin-side layer 23, respectively. Furthermore, measurement positions (e.g., five positions) are determined in the width direction of the cross-sectional image, and the thickness of each of the layers 21 to 23 at each measurement position is obtained. Preferably, cross-sectional images are captured at multiple positions in the longitudinal direction of the absorbent body 20 to obtain the thickness of each of the layers 21 to 23. The average value of the obtained thicknesses is calculated for each of the layers 21 to 23, and this is defined as the average thickness t1 of the skin-side layer 21 (first thickness t1), the average thickness t2 of the intermediate layer 22 (second thickness t2), and the average thickness t3 of the non-skin-side layer 23 (third thickness t3). When measuring the thickness, portions other than the low basis weight regions 211, 221, and 231 are measured. Furthermore, when the absorbent layer is bonded to adjacent sheet portions (core wrap sheets 25, 26, nonwoven fabric 27) via an adhesive, such as the skin-side upper layer 24, the skin-side layer 21, and the middle layer 22, it is difficult to identify the part where the material (liquid absorbent fiber, SAP) constituting each absorbent layer is actually bonded and fixed to the adjacent sheet portion with the adhesive. Therefore, when it can be determined that adhesive exists between the absorbent layer and the adjacent sheet portion, the distance between adjacent sheet portions in the thickness direction is measured as the "thickness of the absorbent layer."

[0122] Using the above-mentioned method, five samples were prepared by cutting the longitudinal end of the absorbent body 20 and then cutting the absorbent body 20 so that the longitudinal length was 10 mm from that point.The average thicknesses when measured were as follows: for size S, the first thickness t1 was 0.41 mm, the second thickness t2 was 0.99 mm, and the third thickness t3 was 0.47 mm; and for size XXL, the first thickness t1 was 0.56 mm, the second thickness t2 was 1.47 mm, and the third thickness t3 was 0.63 mm.

[0123] In this embodiment, the average basis weight of the non-skinside layer 23 is higher than the average basis weight of the skinside layer 21. A suitable average basis weight of the non-skinside layer 23 is 50 g / m 2 ~350g / m 2 Specifically, when the diaper 1 is a size S, the average basis weight of the non-skinside layer 23 is 173 g / m 2 The average basis weight of the skin side layer 21 is preferably about 82 g / m 2 When the diaper 1 is an XXL size, the average basis weight of the non-skin side layer 23 is about 300 g / m 2 The average basis weight of the skin side layer 21 is preferably about 171 g / m 2 The skin side layer 21 with a low average basis weight is less likely to swell after retaining water, and therefore the skin side layer 21 is less likely to suffer from absorption inhibition due to swelling of SAP. As a result, the feel of the skin side (gritty feeling of SAP) is less likely to deteriorate.

[0124] In addition, at least one of the skin side layer 21, the intermediate layer 22, and the non-skin side layer 23 has a basis weight of the absorbent core (i.e., the total basis weight of the liquid absorbent fiber 201 and the SAP: g / m) that is smaller than that of the surrounding area. 2 4, in the absorbent body 20 of this embodiment, the skin side layer 21 and the intermediate layer 22 have low basis weight regions 211, 221, and similarly, the non-skin side layer 23 also has a low basis weight region 231.

[0125] Therefore, when the wearer excretes in the diaper 1 and the absorbent body 20 receives the excreted liquid, the excreted liquid is quickly drawn from the low basis weight region 211 into the interior of the absorbent body 20 (intermediate layer 22). The liquid-absorbent fiber 201 has a faster liquid absorption rate than SAP. Since the volume occupancy of the liquid-absorbent fiber 201 is high in the intermediate layer 22, the excreted liquid that migrates from the low basis weight region 211 to the intermediate layer 22 is quickly and temporarily absorbed by the intermediate layer 22. Thereafter, the excreted liquid absorbed between the fibers of the liquid-absorbent fiber 201 in the intermediate layer 22 gradually migrates due to gravity to the non-skinside layer 23. Furthermore, since the intermediate layer 22 also has a low basis weight region 221, excreted liquid is more likely to migrate from the low basis weight region 221 to the non-skinside layer 23, and more likely to migrate from the low basis weight region 231 of the non-skinside layer 23 to a deeper portion of the non-skinside layer 23. Therefore, excreted liquid is easily drawn deep into the absorbent core, improving absorbency. In addition, since the volume occupancy of SAP in the non-skin side layer 23 is high, excreted liquid is firmly absorbed and retained by SAP in the non-skin side layer 23.

[0126] Furthermore, the low basis weight region 211 of the skin side layer 21 is preferably a slit penetrating the skin side layer 21 in the thickness direction. In this case, excreted liquid falls into the low basis weight region 211, and therefore the migration speed of excreted liquid from the skin side layer 21 to the intermediate layer 22 increases.

[0127] However, this is not limited to the above. Although not shown, the liquid-absorbent fibers 201 or SAP may be present in the low basis weight region 211 of the skin side layer 21. Alternatively, the low basis weight region 211 may be a region of the skin side layer 21 that is recessed in the thickness direction.

[0128] Similarly, the low basis weight region 231 of the non-skin side layer 23 may be a slit penetrating in the thickness direction, or the low basis weight region 231 may contain liquid absorbent fibers 201 or SAP, or the low basis weight region 231 may be partially recessed in thickness.

[0129] 6A are integrally formed and have the same planar shape. The skin side layer 21 and the intermediate layer 22 have narrowed portions 212, 222 narrowed inward in the width direction at the longitudinal center (FIG. 5). When the skin side layer and the intermediate layer 22 are divided into thirds at their maximum longitudinal length, the central region is defined as the longitudinal center, and at least a part of the narrowed portions 212, 222 may be located there.

[0130] 6B has three rectangular divided regions 23a-23c that are long in the longitudinal direction. The three divided regions 23a-23c are arranged side by side at intervals in the width direction. Two regions between the three divided regions 23a-23c become low basis weight regions 231 (slits) of the non-skin side layer 23. The two low basis weight regions 231 are arranged symmetrically in the width direction across the center line CL2 of the non-skin side layer 23 in the width direction.

[0131] When the skin-side layer 21 and the intermediate layer 22 have the constricted portions 212, 222 as described above, the non-skin-side layer 23 has a portion in the longitudinal center of the diaper 1 whose widthwise length L1 is longer than the widthwise lengths of the skin-side layer 21 and the intermediate layer 22, as shown in Fig. 5 . The widthwise length L1 of the non-skin-side layer 23 here refers to the length from one widthwise end 23ae of the divided region 23a of the non-skin-side layer 23 to the other widthwise end 23ce of the divided region 23c. Having a portion of the non-skin-side layer 23 that is longer than the widthwise lengths of the skin-side layer 21 and the intermediate layer 22 allows the non-skin-side layer 23 to absorb excrement that is not fully absorbed by the skin-side layer 21 and the intermediate layer 22, thereby preventing leakage. Furthermore, the number of layers decreases in the longer widthwise portions of the non-skin-side layer 23, thereby reducing rigidity. Here, by providing a region with reduced rigidity within the range where the constricted portions 212, 222 exist, the fit of the crotch area is improved when worn.

[0132] 5, the maximum length L2 of the skin-side layer 21 and the intermediate layer 22 in the width direction is preferably longer than the maximum length L3 (and similarly, L1) of the non-skin-side layer 23. In the longitudinal central portion of the diaper 1, the skin-side layer 21 and the intermediate layer 22 have a portion where their width (length in the width direction) is narrower than the width (L1) of the non-skin-side layer 23, which reduces the SAP on the skin-side side of the crotch area, resulting in a comfortable skin contact. In addition, in portions other than the longitudinal central portion, the maximum length L2 of the skin-side layer 21 and the intermediate layer 22 is longer than the maximum length L3 of the non-skin-side layer 23, which allows for more effective absorption and diffusion of excreted liquid in areas closer to the skin than the non-skin-side layer 23.

[0133] 5, in this embodiment, the length L4 of the skin side layer 21 and the intermediate layer 22 in the longitudinal direction is longer than the length L5 of the non-skin side layer 23. If the length of the non-skin side layer 23 in the longitudinal direction were longer, excreted fluid would be less likely to migrate from the skin side beyond the skin side layer 21 and the intermediate layer 22. However, by arranging the skin side layer 21 and the intermediate layer 22 beyond the non-skin side layer 23 in the longitudinal direction, excreted fluid can be effectively migrated along the entire length of the non-skin side layer 23.

[0134] 5, in a plan view of the absorbent cores 21-23, it is preferable that the low basis weight region 211 of the skin side layer 21, the low basis weight region 221 of the intermediate layer, and the low basis weight region 231 of the non-skin side layer have overlapping portions. The skin side layer 21 and the intermediate layer 22 of this embodiment each have two low basis weight regions 211, 221. The two low basis weight regions 211, 221 of the skin side layer 21 and the intermediate layer 22 each overlap with two low basis weight regions 231 of the non-skin side layer 23.

[0135] This allows excreted liquid that has flowed into the low basis weight region 211 of the skin side layer 21 and the low basis weight region 221 of the intermediate layer 22 to easily flow directly into the low basis weight region 231 of the non-skin side layer 23. This allows excreted liquid to be more quickly drawn deep into the absorbent cores 21-23. Furthermore, in the low basis weight regions 211-231, absorption is less likely to be hindered by swelling of SAP, improving the absorption rate.

[0136] In this embodiment, low basis weight regions are provided in all of the skin side layer 21, intermediate layer 22, and non-skin side layer 23, but the present invention is not limited to this, and when one of the skin side layer 21, intermediate layer 22, and non-skin side layer 23 has a low basis weight region, at least one of the layers other than the layer having the low basis weight region may further have a low basis weight region (corresponding to another low basis weight region), and may have a portion where the low basis weight region overlaps with another low basis weight region in a plan view of the absorbent cores 21 to 23. This similarly forms a passage for excreted liquid, and excreted liquid can easily migrate from a layer having a low basis weight region to a layer having another low basis weight region.

[0137] Furthermore, the shape, size, number, and position of the low basis weight regions 211-231 in each layer are not particularly limited. For example, each layer may have one low basis weight region 211-231, which may be located on the center line CL2 in the width direction of the absorbent cores 21-23. Furthermore, the low basis weight regions 21-23 in each layer 21-23 may completely overlap, or multiple low basis weight regions 221-231 may be located at intervals in the longitudinal direction.

[0138] As described above, the skin-side layer 21 has a low-basis-weight region 211 in which the absorbent core has a lower basis weight than the surrounding area, and the skin-side upper layer 24, which is disposed closer to the skin than the skin-side layer 21, is disposed so as to overlap the low-basis-weight region 211 of the skin-side layer 21 in a planar view, although not shown. The skin-side upper layer 24 is laminated so as to cover at least the shape of the skin-side layer 21 shown in Fig. 5, and in the constricted portion 212, the skin-side upper layer 24 is also laminated on portions outer than both ends of the constricted portion 212 in the width direction. There is a risk that SAPs from the periphery of the low-basis-weight region 211 may shift and intrude into the low-basis-weight region 211. However, the presence of the skin-side upper layer 24 covering the low-basis-weight region 211 from the skin side makes it less likely that SAPs contained in regions outer than the low-basis-weight region 211 in the width direction and length direction shift, making it easier to maintain the shape of the low-basis-weight region 211.

[0139] The skin side layer 21 may have a different type of SAP than the non-skin side layer 23. For example, the SAP of the skin side layer 21 desirably has a slower liquid absorption rate as measured by the vortex method than the SAP of the non-skin side layer 23.

[0140] This allows the excreted liquid to diffuse in the planar direction and migrate to the intermediate layer 22 before being absorbed by the SAP of the skin-side layer 21. As a result, the absorbent cores 21-23 can be utilized more effectively, improving absorption performance. Furthermore, by absorbing more excreted liquid in the non-skin-side layer 23, rewetting of the skin-side layer 21 can be suppressed.

[0141] The liquid absorption rate of SAP by the vortex method can be measured by a known method. For example, 50.0 ml (±0.5 ml) of saline solution with a concentration of 0.900% (±0.009%) and a temperature of 25°C (±2°C) is placed in a 100 ml beaker. The beaker is then placed on a magnetic stirrer and the stir bar is placed inside the beaker. The stir bar is then rotated at 600 rpm (±30 rpm) to ensure that the saline solution in the beaker forms a stable vortex. A stopwatch is then started from the moment 2.00 g (±0.02 g) of the SAP to be measured, taken from Diaper 1, is placed in the beaker. The time from when the vortex disappears and the liquid level becomes horizontal is measured. The longer this time, the slower the liquid absorption rate.

[0142] Furthermore, when the absorbent body 20 of this embodiment does not include the above-described skin-side upper layer 24, i.e., when the skin-side layer 21 is the layer closest to the skin of the absorbent core, it is preferable that the liquid permeation rate under load of the SAP included in the skin-side layer exceeds 10 seconds. If the liquid permeation rate of the excreted liquid is excessively fast when the skin-side layer 21 receives excreted liquid, the excreted liquid will migrate to the intermediate layer 22 without sufficiently diffusing in the width or length directions of the skin-side layer 21, which may result in a deterioration in the water retention performance of the absorbent core as a whole. Furthermore, if the SAP swells only in the portion that receives the excreted liquid, the absorbent core may become locally thick. In contrast, by setting the liquid permeation rate under load in the skin-side layer to exceed 10 seconds, the water retention of the absorbent core is improved, leading to leakage prevention, and local thickening of the absorbent core can be suppressed, compared to the opposite case.

[0143] The liquid permeation rate under load of SAP in the layer closest to the skin of the absorbent core can be measured, for example, by the method described in JP 2019-41876 A. Specifically, 0.32±0.005 g of superabsorbent polymer (SAP) was immersed in 100 mL of physiological saline (0.9% by mass sodium chloride solution) in a 100 mL glass beaker and left for 60 minutes. A separate cylindrical filtration tube was prepared at the bottom of the opening of a vertically standing cylinder (inner diameter 25.4 mm) equipped with a wire mesh (150 μm mesh, Sansho Hanbai Biocolumn Sintered Stainless Steel Filter 30SUS) and a capillary tube (inner diameter 4 mm, length 8 cm) with a stopcock (inner diameter 2 mm). With the stopcock closed, the entire contents of the beaker, including the swollen test sample, were poured into the cylindrical tube. Next, a 2 mm diameter cylindrical rod with a 25 mm diameter wire mesh at its tip, with 150 μm mesh openings, is inserted into the cylindrical filter tube so that the wire mesh contacts the test sample. A weight is then placed on the test sample to apply a 2.0 kPa load. After leaving the tube in this state for 1 minute, the stopcock is opened to allow the liquid to flow. The time T1 (seconds) until the liquid level in the cylindrical filter tube reaches the 40 mL mark from the 60 mL mark (i.e., 20 mL of liquid passes through) is measured. The measured time T1 (seconds) is used to calculate the liquid passage rate under load at 2.0 kPa using the formula: Liquid passage rate under load (seconds) = T1 - T0. Note that T0 (seconds) is the time required for 20 mL of saline to pass through the wire mesh without the test sample in the cylindrical filter tube. Measurements are carried out at a temperature of 23±2°C and a relative humidity of 50±5%, and the superabsorbent polymer (SAP) is kept in the same environment for at least 24 hours before measurement.

[0144] FIG. 7 is a schematic plan view of the absorbent body 20 as seen from the skin side. As shown in FIG. 7, in this embodiment, the skin side layer 21 has a plurality of compressed dots 50 formed by compressing the skin side layer 21 (absorbent core 21) in a dotted pattern in the thickness direction. These "compressed dots 50" are formed by embossing the absorbent core 21 in the thickness direction. The compression increases the fiber density of the absorbent core 21 compared to uncompressed portions. In this embodiment, the compressed dots 50 are formed as a collection of dots (circles), but the compressed dots 50 may also be formed as lines (straight lines, curves), for example. Alternatively, the compressed dots or lines may be formed discretely within a predetermined region. Furthermore, the compressed dots 50 are arranged in a pattern that appears as a dotted grid pattern (a so-called quilting pattern) as a whole, as shown in FIG. 7, but other patterns may also be used.

[0145] These compressed dots 50 reduce clumps of SAP during compression, suppressing the gritty feel of SAP. Furthermore, localized compression prevents collapse of the absorbent body 20 without impairing the flexibility of the absorbent cores 21-24. Note that the invention is not limited to providing multiple compressed dots 50 on the skin side layer 21, as long as at least one of the skin side layer 21 and the non-skin side layer 23 has compressed dots 50.

[0146] FIG. 8 is a partially enlarged plan view showing the adhesive HMA that bonds the core wrap sheet 25 and the skin-side upper layer 24 (skin-side layer 21). A strip-shaped adhesive HMA is applied to the non-skin-side surface of the core wrap sheet 25 in the thickness direction. Furthermore, on the skin-side surface of the skin-side upper layer 24 (skin-side layer 21), the outer edge region in the width direction is defined as the outer edge region TR, and the region inside the outer edge region TR is defined as the inner region UR. The total adhesive area per unit area in the inner region UR is greater than the total adhesive area per unit area in the outer edge region TR. Because the skin-side upper layer 24 is thinner than the skin-side layer 21, the strip-shaped adhesive HMA applied to the non-skin-side surface of the core wrap sheet 25 penetrates the skin-side layer 21. In the inner region UR, where the adhesive HMA is more abundant, the adhesive HMA easily fixes the SAP contained in the skin-side layer 21. This fixation makes the SAP less likely to move, thereby preventing the SAP from being exposed to the skin-side surface of the absorbent body 20. Furthermore, with this configuration, SAP lumps are less likely to form when the SAP swells, reducing the discomfort of the texture.

[0147] Furthermore, the average width of the strip-shaped adhesive HMA applied to the non-skin-side surface of the core wrap sheet 25 (the skin-side surface) is smaller than the average particle size of the SAP particles, allowing the adhesive to easily penetrate between the SAP particles. Specifically, the average width of the strips is 0.016 to 0.018 mm, while the average particle size of the SAP particles is 0.3 to 0.4 mm (see FIG. 9). FIG. 9 shows an image of the non-skin-side surface of the core wrap sheet 25 in the inner region UR of the diaper 1 before use. That is, FIG. 9 shows the state before the SAP particles absorb liquids such as excrement and swell. In this state, the minimum inter-intersection distance of the strip-shaped adhesive is smaller than the particle size (average particle size) of the SAP particles. For example, the inter-intersection distance di of a certain strip-shaped adhesive shown in FIG. 9 is clearly smaller than the diameter Dsap of a certain SAP. Furthermore, during use of the diaper 1, the SAP particles absorb liquids such as excrement and swell, so the particle size (average particle size) of the SAP particles becomes even larger than the diameter Dsap shown in FIG. 9. In other words, the minimum distance between the intersections of the strip-shaped adhesive is smaller than the particle size (average particle size) of the SAP particles when they are fully swollen. This makes it difficult for the SAP particles to escape from the mesh formed by the intersections of the numerous strip-shaped adhesive when absorbing water (when the SAP is fully swollen), thereby restricting the movement of the SAP. This makes it difficult for SAP clumps to form even after the SAP particles have fully swelled, reducing the gritty feel when touched.

[0148] The average particle size of SAP can be measured using an electromagnetic sieve shaker (e.g., AS-200 manufactured by Retsch) as follows. The electromagnetic sieve shaker has sieves No. 1 to No. 7 with different mesh sizes (e.g., mesh sizes: 850, 600, 500, 355, 300, 250, and 150 μm) and a tray. First, the weights of the sieves No. 1 to No. 7 and the tray are measured and taken as measurement value A. Next, from bottom to top, the tray and sieves with mesh sizes of 150, 250, 300, 355, 500, 600, and 850 μm are stacked and set in the shaker. Next, 50 g of SAP is placed on the top sieve with an 850 μm mesh, and the sieve is covered and secured with a pressure pad. Next, the shaker is set to a 1.35 mm amplitude (the amplitude adjustment dial is 45 for the AS-200 model), continuous operation, and a 30-minute shaking test is performed. After the shaking test is completed, the SAP remaining on each of the sieves No. 1 through No. 7, as well as the weight of the sieve and the pan, are measured and recorded as measurement value B. From these data, the SAP particle size distribution is calculated as (BA) / (total weight of SAP remaining on each sieve and on the pan) × 100 (%). For example, if the shaking test results for a certain sample show that 48.3% of the SAP remains on the No. 4 sieve (355 μm mesh), this means that 48.3% of the SAP in that sample is in the 355–500 μm particle size range. From these data, the average SAP particle size can be determined. Alternatively, SAP particle size can be calculated from magnified microscope images instead of using shaking tests.

[0149] 10A, 10B, and 11 are cross-sectional views of modified examples of the absorbent cores 21 to 24. As shown in the modified example of FIG. 10A, the liquid-absorbent fibers 201 do not have to be arranged in the low basis weight region 221 of the intermediate layer 22. Preferably, the low basis weight region 221 of the intermediate layer 22 is a slit. In this way, excreted liquid is not temporarily absorbed by the liquid-absorbent fibers 201 in the low basis weight region 221 of the intermediate layer 22, and therefore the excreted liquid can be quickly drawn deeper into the non-skin side layer 23.

[0150] 10B, the intermediate layer 21 and the non-skin side layer 23 may be laminated adjacent to each other in the thickness direction without an adhesive or nonwoven fabric (nonwoven fabric 27 in this embodiment). This prevents the adhesive or nonwoven fabric from interfering with the transfer of excreted fluid from the intermediate layer 21 to the non-skin side layer 23, and increases the rate of absorption by the non-skin side layer 23.

[0151] 11, the intermediate layer 22 and the non-skinside layer 23 are integrally formed, and a nonwoven fabric 27 is provided closer to the skin than the intermediate layer 22. In this modification, the total water retention capacity of the SAP present in the skinside layer 21 is configured to be greater than the total water retention capacity of the SAP present in the non-skinside layer 23. This configuration makes it difficult for the non-skinside layer 23 to swell even after absorbing excrement, and reduces the discomfort felt by the SAP when changing the diaper 1 due to its gritty texture. Furthermore, the skinside layer 21, which has a high total water retention capacity, can firmly absorb and retain excrement, ensuring absorbency.

[0152] 11 , in contrast to this embodiment, the average total area occupied by SAPs per unit area in a cross section taken along the thickness direction of the skin-side layer 21 is larger than the average total area occupied by SAPs per unit area in a cross section taken along the thickness direction of the non-skin-side layer 23. When the skin-side layer 21 is the layer with a larger average total area occupied by SAPs per unit area, the SAPs can retain excrement and suppress rewetting. When the non-skin-side layer 23 is the layer with a smaller average total area occupied by SAPs per unit area, the SAPs are less likely to feel uncomfortable to the touch when changing the diaper 1.

[0153] 11 , the liquid-absorbent fibers 201 do not have to be disposed in the low basis weight region 231 of the non-skin side layer 23. Preferably, the low basis weight region 231 of the non-skin side layer 23 is a slit. This prevents excreted liquid from being temporarily absorbed by the liquid-absorbent fibers 201 in the low basis weight region 231 of the non-skin side layer 23, allowing the excreted liquid to be quickly drawn deeper into the non-skin side layer 23.

[0154] 11, the skin side layer 21 and the intermediate layer 22 may be laminated adjacent to each other in the thickness direction without the interposition of the nonwoven fabric 27 or adhesive. This prevents the adhesive or nonwoven fabric from interfering with the transfer of excreted fluid from the skin side layer 21 to the intermediate layer 22, and increases the rate of absorption by the intermediate layer 22.

[0155] Furthermore, the intermediate layer 22 is not limited to being formed integrally with either the skin side layer 21 or the non-skin side layer 23, but may be formed integrally with both. Alternatively, the three layers 21 to 23 may be formed individually and then laminated. In this case, a nonwoven fabric or an adhesive may or may not be provided between the skin side layer 21 and the intermediate layer 22, and between the intermediate layer 22 and the non-skin side layer 23, respectively.

[0156] Furthermore, the superabsorbent polymer (SAP) used in this embodiment is preferably spherical rather than crushed. By uniformly stacking spherical SAP, which have a uniform shape and a smaller surface area than crushed SAP, the absorbent body 20 can be made thinner, and the absorbent body 20 is less likely to become hard when made thinner.

[0157] Furthermore, in the absorbent body 20 of the diaper 1, the core wrap sheets 25, 26 covering the absorbent core (SAP particles) are preferably formed from a hydrophilic SMS (spunbond-meltblown-spunbond) nonwoven fabric, spunlace nonwoven fabric, or the like. Nonwoven fabrics are generally stronger and more tear-resistant than tissues and the like, making them suitable as base sheets for forming the absorbent body 20. For example, during the manufacture of the absorbent body 20 of the diaper 1, when adhesive is applied or SAP particles are laminated while the nonwoven fabric is conveyed in the conveying direction as the base sheet, the tear-resistant nonwoven fabric base sheet allows for the formation of an absorbent body (absorbent core) with a stable shape. Furthermore, conveying the base sheet while suctioning it with a suction mechanism or the like can facilitate the fixation of the SAP particles on the base sheet. Furthermore, when the nonwoven fabric is an SMS nonwoven fabric, the material is thinner than other nonwoven fabrics, thereby improving the flexibility of the absorbent body 20. Furthermore, when the nonwoven fabric is a spunlace nonwoven fabric, the gritty feel of SAP can be reduced and the absorption rate can be improved because spunlace nonwoven fabric is a bulky and highly absorbent material.

[0158] Furthermore, in the absorbent cores 21-23, it is preferable that a layer having a high volume occupancy of SAP that does not contain the liquid-absorbent fiber 201 is present as the skin-side layer 21 or the non-skin-side layer 23. In this embodiment, the non-skin-side layer 23 is a layer that does not contain the liquid-absorbent fiber 201. Such a layer that does not contain the liquid-absorbent fiber 201 is more susceptible to liquid transfer than a layer that contains the liquid-absorbent fiber 201. The presence of the non-skin-side layer 23 having a high volume occupancy of SAP that does not contain the liquid-absorbent fiber 201 improves absorbency. Furthermore, in the absorbent body 20 shown in the modified example of FIG. 11 , a layer having a high volume occupancy of SAP that does not contain the liquid-absorbent fiber 201 is present as the skin-side layer 21. In such a case, rewetting can be suppressed by the skin-side layer 21 firmly absorbing the liquid.

[0159] The skin-side layer 21 of this embodiment contains the liquid-absorbent fiber 201 and has a high volume occupancy of SAP, but the volume occupancy of SAP is preferably 80% or less. In the area where the skin-side layer 21 and the intermediate layer 22 are adjacent to each other, the SAP particles and the liquid-absorbent fiber 201 are entangled, making the SAP less likely to crumble. As described above, the preferred average basis weight of the non-skin-side layer 23, which does not contain the liquid-absorbent fiber 201, is 50 g / m 2 ~350g / m 2 The non-skin-side layer 23, which does not contain the liquid-absorbent fiber 201, is uniformly layered with little overlap in the thickness direction, reducing the gritty feel of the SAP while ensuring absorbency. This configuration allows the SAP to be distributed in one product (absorbent body 20) without being concentrated in one place, and ensures absorbency while reducing the gritty feeling.

[0160] ===Other=== The above-described embodiments are intended to facilitate understanding of the present invention and are not intended to limit the present invention. The present invention may be modified or improved without departing from the spirit thereof, and the present invention includes equivalents thereof.

[0161] In the above-described embodiment, the non-skinside layer 23 illustrated in FIG. 5 has a shorter longitudinal length than the skinside layer 21 and the intermediate layer 22, but this is not limited thereto and the longitudinal lengths may be the same. Conversely, the longitudinal length of the back side (rear side) of the non-skinside layer 23 may be even shorter than the length in this embodiment. In this case, material can be reduced, and the rigidity of the back-side absorbent core is reduced, increasing its flexibility. Furthermore, because the back-side region is also away from the wearer's urinary excretion opening, leakage of excreted fluid is less likely to occur even if the longitudinal length of the non-skinside layer 23 is short.

[0162] In the above-described embodiment, three layers, namely, the skin-side layer 21, the intermediate layer 22, and the non-skin-side layer 23, are laminated over substantially the entire area of the absorbent cores 21-23. However, this is not limiting, and the three layers (21-23) may be laminated at any location. Preferably, the three layers (21-23) are laminated at and near the position where the wearer's urinary excretion opening contacts when the diaper 1 is worn. Similarly, the low-basis-weight regions 211, 221 of the skin-side layer 21 and the intermediate layer 22 and the low-basis-weight region 231 of the non-skin-side layer 23 may also be provided at and near the position where the wearer's urinary excretion opening contacts. This allows the excreted liquid to be quickly drawn to the innermost part of the absorbent cores 21-23 at positions that directly receive a large amount of excreted liquid during excretion.

[0163] In the above-described embodiment, the skin side layer 21 and the intermediate layer 22 are integrally formed, but this is not limiting, and the skin side layer 21 and the intermediate layer 22 do not have to be integrally formed. For example, an adhesive or a nonwoven fabric may be disposed between the skin side layer 21 and the intermediate layer 22. The adhesive can better fix the SAP contained in the skin side layer 21, and the nonwoven fabric can further diffuse excreted liquid in the planar direction on the nonwoven fabric.

[0164] In addition, an adhesive is applied to the skin side of the core wrap sheet 26 (sheet material) in this embodiment to secure the SAP particles, and the residual stress of the applied adhesive is preferably 2 KPa or more and 20 KPa or less. The adhesive that secures the SAP particles is required to have a resistance (residual stress) that prevents the SAP particles from falling off the core wrap sheet 26 (base sheet) even when external forces associated with the swelling of the SAP particles are applied. If the residual stress of the adhesive is 2 KPa or more and 20 KPa or less, there is a high probability that the SAP fixation rate will be 40% or more, making it possible to make the non-skin side layer 23 less likely to collapse.

[0165] Here, the SAP fixation rate indicates the proportion of SAP that does not fall off when the absorbent sheet being measured is placed in physiological saline (0.9% by mass saline) being stirred at a specified rotation speed, and can be an indicator of the fixation of SAP to the base sheet after absorption and swelling.The higher the SAP fixation rate, the stronger the fixation of SAP to the base sheet in the absorbent sheet, indicating that SAP is less likely to fall off, not only before use but also after absorbing liquid.The SAP fixation rate is measured according to the following procedures 1 to 5.

[0166] (Step 1) Prepare a measurement sample from an absorbent sheet that is 5 cm square in plan view. The edges of the measurement sample are grasped and the measurement sample is temporarily suspended vertically, and then the weight of the measurement sample (initial sample weight) is measured. (Step 2) The measurement sample is entirely immersed in physiological saline, and the measurement sample is removed from the physiological saline 30 minutes after the start of immersion. (Step 3) Place a cylindrical stirring bar with a diameter of 35 mm and an axial length of 12 mm and 300 ml of saline in a 300 ml beaker, and stir the saline by rotating the stirring bar at a rotation speed of 60 ± 5 rpm using a magnetic stirrer. Add the measurement sample that has been subjected to Step 2 to the stirred saline, and remove the measurement sample from the saline 30 seconds after addition. (Step 4) After step 3, the wet measurement sample is left to stand in a thermostatic bath set at 105°C for 12 hours, and then the weight of the dry measurement sample (weight of the sample after stirring) is measured. (Step 5) The total weight of the components other than the water-absorbent polymer is subtracted from each of the initial sample weight and the sample weight after the stirring treatment to calculate the initial water-absorbent polymer weight (W0) and the water-absorbent polymer weight after the stirring treatment (W1), respectively. Then, the water-absorbent polymer fixing rate of the measurement sample (absorbent sheet) is calculated using the following formula. Fixation rate of water-absorbing polymer (%) = (W1 / W0) x 100

[0167] In step 1, the measurement sample (a 5 cm square absorbent sheet in plan view) is grasped by its edge and temporarily suspended vertically in order to remove any loose objects, such as a water-absorbent polymer that is loosely disposed on the base sheet (for example, a water-absorbent polymer that is not secured with an adhesive or the like but is simply sprinkled from above the base sheet). The hanging operation of the measurement sample involves simply grasping the edge of the measurement sample and suspending it approximately vertically for approximately 3 to 5 seconds, without striking or violently shaking the suspended measurement sample. Furthermore, when suspending the measurement sample, first, the edge of the measurement sample is grasped using tweezers or the like and suspended for 3 to 5 seconds, and then the edge opposite to the edge grasped during the suspension is grasped and suspended for 3 to 5 seconds. Furthermore, in the above-mentioned step 1, if it is not possible to prepare an absorbent sheet of 5 cm square as the measurement sample (for example, if the size of the measurement sample is less than 5 cm square due to the small size of the absorbent sheet), multiple small measurement samples of less than 5 cm square are taken from the sheet to be evaluated, and the total area of one side of these multiple measurement samples is 25 cm2. Then, for each of the multiple measurement samples, the water-absorbent polymer fixation rate is measured according to the above-mentioned steps 1 to 5, and the average value of the multiple water-absorbent polymer fixation rates thus obtained is taken as the water-absorbent polymer fixation rate of the absorbent sheet.

[0168] Examples of measuring instruments used in step 3 include the following: Magnetic stirrer: HI-304N (HANNA, inverted stirrer) Stirrer: Star head NALGENE (6600-0035) [35φ×12mm] Beaker: 300ml (78φ×103mm)

[0169] The residual stress of the adhesive is measured by the following method. <Method for measuring residual stress in adhesive> Using a rotational rheometer (Anton Paar, model "Physica MCR301"), the adhesive to be measured is placed between a backing plate that is circular in plan view and supports the measurement sample from below, and a pressing plate that is also circular in plan view and is placed above and facing the backing plate. In this state, the adhesive has a circular shape in plan view, a thickness of 1.5 mm, a diameter of 12 mm, and a temperature of 30°C. Then, from this state, the pressing plate is rotated to apply a 30% strain to the adhesive. 20 minutes after applying the strain to the adhesive, the shear stress of the adhesive is measured, and this measurement value is taken as the residual stress of the adhesive.

[0170] In the measurement of the residual stress, if the adhesive to be measured is unused (not applied to a base sheet and not a component of an absorbent sheet), the unused adhesive is used as is for measurement. On the other hand, if the adhesive to be measured is a component of an absorbent sheet, the adhesive is extracted from the absorbent sheet by the solvent extraction method described below, and the extracted adhesive is used for measurement.

[0171] <Solvent extraction method for adhesives> First, an absorbent sheet containing an adhesive is mixed with a solvent capable of dissolving the adhesive in a container such as a beaker to obtain an adhesive solution in which the adhesive is dissolved in the solvent. Next, the adhesive solution is collected from the container, and the adhesive solution is dried under reduced pressure using a rotary evaporator, for example, to remove the solvent from the adhesive solution to obtain an adhesive. The adhesive thus obtained is used as the measurement target for the residual stress measurement. The solvent used to dissolve the adhesive may be selected appropriately depending on the type of adhesive, etc. When the adhesive to be measured is, for example, a hot melt adhesive, examples of solvents used to dissolve the adhesive include toluene, methyl ethyl ketone, and heptane. [Explanation of symbols]

[0172] 1. Pants-type disposable diapers (absorbent articles) 2 side joints, 10. Absorbent body; 12 top sheet, 13a Back sheet (liquid-impermeable sheet), 13b Back seat (exterior seat), 15 leak-proof wall portion, 16 leak-proof wall elastic member, 17 Elastic member around the legs, 20 absorber, 201 Liquid absorbent fibers, SAP Super Absorbent Polymer, 21 skin side layer (absorbent core), 211 low basis weight region, 22 intermediate layer (absorbent core), 221 low basis weight region, 23 Non-skin side layer (absorbent core), 231 Low basis weight region, 24 Upper layer (absorbent core) 25 Core wrap sheet, 26 Core wrap sheet, 27 nonwoven fabrics, 30 Front waistband, 31 skin side sheet, 32 non-skin side sheet, 33 waist elastic member, 34 cover sheets, 40 rear waistband, 41 skin side sheet, 42 non-skin side sheet, 43 waist elastic member; 44 Cover Sheet 50 Point-like compression section TR outer edge area UR inner area

Claims

1. In the unfolded state, the sheet has a longitudinal direction, a width direction, and a thickness direction which are perpendicular to each other, An absorbent article having an absorbent core comprising liquid-absorbent fibers and a superabsorbent polymer, The absorbent core comprises: a skin-side layer having a first thickness and in which the volume occupied by the superabsorbent polymer is greater than the volume occupied by the liquid-absorbent fiber; an intermediate layer having a second thickness, the intermediate layer having a volume occupied by the liquid-absorbent fibers greater than a volume occupied by the superabsorbent polymer; a non-skin side layer having a third thickness and in which the volume occupied by the superabsorbent polymer is greater than the volume occupied by the liquid-absorbent fiber; the intermediate layer is located closer to the skin than the skin side layer in the thickness direction, the non-skin side layer is located closer to the skin than the intermediate layer in the thickness direction, The total water retention capacity of the superabsorbent polymer present in the skin-side layer is different from the total water retention capacity of the superabsorbent polymer present in the non-skin-side layer. An absorbent article characterized by:

2. The absorbent article according to claim 1, The total water retention capacity of the superabsorbent polymer present in the non-skin side layer is greater than the total water retention capacity of the superabsorbent polymer present in the skin side layer. An absorbent article characterized by:

3. In the unfolded state, the sheet has a longitudinal direction, a width direction, and a thickness direction which are perpendicular to each other, An absorbent article having an absorbent core comprising liquid-absorbent fibers and a superabsorbent polymer, The absorbent core comprises: a skin-side layer having a first thickness and in which the volume occupied by the superabsorbent polymer is greater than the volume occupied by the liquid-absorbent fiber; an intermediate layer having a second thickness, the intermediate layer having a volume occupied by the liquid-absorbent fibers greater than a volume occupied by the superabsorbent polymer; a non-skin side layer having a third thickness and in which the volume occupied by the superabsorbent polymer is greater than the volume occupied by the liquid-absorbent fiber; the intermediate layer is located closer to the skin than the skin side layer in the thickness direction, the non-skin side layer is located closer to the skin than the intermediate layer in the thickness direction, an average value of the total area occupied by the superabsorbent polymer per unit area in a cross section of the skin side layer taken along the thickness direction; the average value of the total area occupied by the superabsorbent polymer per unit area in the cross section of the non-skin side layer taken along the thickness direction is different, a skin-side upper layer having a thickness less than the first thickness and a volume occupied by the liquid-absorbent fiber greater than a volume occupied by the superabsorbent polymer; An absorbent article characterized by:

4. The absorbent article according to claim 3, The average value of the total area occupied by the superabsorbent polymer per unit area in the cross section of the non-skin side layer taken along the thickness direction is greater than the average value of the total area occupied by the superabsorbent polymer per unit area in the cross section of the skin side layer taken along the thickness direction. An absorbent article characterized by:

5. The absorbent article according to claim 1, a skin-side upper layer having a thickness less than the first thickness and a volume occupied by the liquid-absorbent fiber greater than a volume occupied by the superabsorbent polymer; An absorbent article characterized by:

6. The absorbent article according to claim 3 or 5, the skin side layer has a low basis weight region in which the basis weight of the absorbent core is lower than that of a surrounding area, The skin side upper layer is disposed so as to overlap the low basis weight region of the skin side layer in a plan view. An absorbent article characterized by:

7. The absorbent article according to claim 1 or 2, The third thickness is greater than the first thickness. An absorbent article characterized by:

8. The absorbent article according to claim 1 or 2, The average basis weight of the non-skinside layer is higher than the average basis weight of the skinside layer. An absorbent article characterized by:

9. The absorbent article according to claim 1 or 3, the skin-side layer has a different type of superabsorbent polymer from the non-skin-side layer, The superabsorbent polymer contained in the skin-side layer has a slower liquid absorption rate as measured by a vortex method than the superabsorbent polymer contained in the non-skin-side layer. An absorbent article characterized by:

10. The absorbent article according to claim 1 or 3, The skin side layer and the intermediate layer are laminated adjacent to each other in the thickness direction without an adhesive or a nonwoven fabric therebetween. An absorbent article characterized by:

11. The absorbent article according to claim 1 or 3, The intermediate layer and the non-skin side layer are laminated adjacent to each other in the thickness direction without an adhesive or a nonwoven fabric therebetween. An absorbent article characterized by:

12. The absorbent article according to claim 1 or 3, At least one of the skin side layer, the intermediate layer, and the non-skin side layer has a low basis weight region in which the basis weight of the absorbent core is lower than that of the surrounding area. An absorbent article characterized by:

13. The absorbent article according to claim 1 or 3, one of the skin side layer, the intermediate layer, and the non-skin side layer has a low basis weight region in which the basis weight of the absorbent core is lower than that of a surrounding area; At least one of the layers among the skin side layer, the intermediate layer, and the non-skin side layer other than the layer having the low basis weight region has another low basis weight region in which the basis weight of the absorbent core is lower than that of a surrounding area, In a plan view of the absorbent core, the low basis weight region has a portion overlapping with the other low basis weight region. An absorbent article characterized by:

14. The absorbent article according to claim 1 or 3, In the center portion of the absorbent article in the longitudinal direction, The non-skin side layer has a portion whose length in the width direction is longer than the lengths in the width direction of the skin side layer and the intermediate layer. An absorbent article characterized by:

15. 15. The absorbent article of claim 14, In the width direction, The maximum length of the skin side layer and the intermediate layer is greater than the maximum length of the non-skin side layer. An absorbent article characterized by:

16. The absorbent article according to claim 1 or 3, In the longitudinal direction, The length of the skin side layer and the intermediate layer is longer than the length of the non-skin side layer. An absorbent article characterized by:

17. The absorbent article according to claim 1 or 3, At least one of the skin side layer and the non-skin side layer has a plurality of compressed dots formed to compress the absorbent core in the thickness direction. An absorbent article characterized by:

18. The absorbent article according to claim 1 or 3, A core wrap sheet is disposed on the skin side of the skin side layer in the thickness direction, A strip-shaped adhesive is provided on the non-skin side surface of the core wrap sheet in the thickness direction, the average width of the adhesive strip is smaller than the average particle size of the superabsorbent polymer; The minimum distance between the intersections of the strip-shaped adhesive is smaller than the average particle size of the superabsorbent polymer when maximally swollen. An absorbent article characterized by:

19. The absorbent article according to claim 1 or 2, having an absorbent body, The absorbent body has an absorbent core including a skin side layer, an intermediate layer, and a non-skin side layer laminated at least in the thickness direction, An absorbent article, wherein the intermediate layer does not contain a nonwoven fabric.

20. 20. The absorbent article of claim 19, An absorbent article, wherein the layer of the absorbent core closest to the skin does not contain water-absorbent resin powder.

21. 20. The absorbent article of claim 19, An absorbent article characterized in that the superabsorbent polymer contained in the layer closest to the skin of the absorbent core has a liquid permeation rate under load of more than 10 seconds.

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