Absorbent article

Abstract

To provide an absorbent article suppressed in discomfort caused by stiffness in a crotch part of a wearer, and deterioration of adhesion to the crotch part after excretion while suppressing leakage of excretion liquid.SOLUTION: An absorbent article (1) having an absorbent core (11) has a crotch elastic member (40) that expands and contracts in a longitudinal direction. At least a part of the crotch elastic member (40) is provided in a central part in a right-left direction of a crotch part as a central region formed when dividing the absorbent article (1) into three parts in the longitudinal direction. In a central position of the absorbent article (1) in the longitudinal direction, the absorbent core (11) is a monolayer. When a hanging-up testing of hanging up an end part at a waist side of the absorbent article (1) in a two-folded state in the longitudinal direction, and both end parts in the right-left direction is performed after dropping liquid with the central position in the right-left direction in a two-folded position in the longitudinal direction as a dropping position, the central part in the right-left direction of a bottom edge of the absorbent article (1) forms a shape protruding upward.SELECTED DRAWING: Figure 8

Description

[Technical Field]

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

[0002] Patent Document 1 discloses an incontinence pants-type diaper as an absorbent article (wearing article) in which a first elastic member is arranged at approximately the center of the width direction of the absorbent article so as to extend along the longitudinal direction of the absorbent article. The first elastic member is said to improve the adhesion between the excretory area (crotch area) and the absorber, and to prevent excreted fluid from leaking out along the wearer's skin even in cases where the urine rate is slow. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 5756093 Summary of the Invention [Problem to be solved by the invention]

[0004] Patent Document 1 exemplifies an absorbent body with a two-layer structure in which a first absorbent layer and a second absorbent layer overlap at the longitudinal center position that abuts against the wearer's crotch. While the two-layer portion ensures a sufficient amount of excrement absorbed, it is thicker and may be stiff and uncomfortable for the wearer. Furthermore, when the absorbent absorbs excrement, it sags due to its own weight. This reduces the absorbent's ability to adhere to the wearer's crotch area, leading to discomfort for the wearer. Patent Document 1 addresses leakage in cases where the urine flow rate is slow or the amount of urine is large, but does not consider the deformation of the absorbent after excretion. In particular, in the case of a two-layer absorbent, if the first and second absorbent layers have different widths, the boundary between the first and second layers is located on both sides of the absorbent in the width direction, and this boundary is likely to become the fold point for the absorbent. Therefore, after the absorbent absorbs excrement, the first elastic member cannot adhere the absorbent to the wearer's crotch area, which may result in the absorbent sagging.

[0005] The present invention has been made in consideration of the above-mentioned problems, and its object is to provide an absorbent article that suppresses leakage of excrement while suppressing stiffness in the crotch area of ​​the wearer and discomfort caused by a decrease in adhesion to the crotch area after excretion. [Means for solving the problem]

[0006] The main invention to achieve the above object is: 1. An absorbent article having an absorbent core, In the deployed and extended state, having a longitudinal direction, a left-right direction, and a thickness direction which intersect with one another, The garment has a crotch elastic member that stretches in the longitudinal direction, At least a part of the crotch elastic member is provided in the left-right central portion of the crotch portion, which is the central region when the absorbent article is divided into three equal parts in the longitudinal direction, At a central position of the absorbent article in the longitudinal direction, the absorbent core is a single layer, This absorbent article is characterized in that when a liquid is dripped onto the absorbent article at the center position in the left-right direction at the folded position in the longitudinal direction, and then a lifting test is conducted in which the waist side end of the absorbent article, which is folded in half in the longitudinal direction, and both ends in the left-right direction are grasped and lifted, the center position in the left-right direction of the lower end of the absorbent article forms a convex shape facing upward. 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 suppresses leakage of excrement while suppressing stiffness in the crotch area of ​​the wearer and discomfort caused by a decrease in adhesion to the crotch area after excretion. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a schematic front view of a pants-type disposable diaper 1. FIG. [Figure 2] 1 is a schematic plan view of a diaper 1 in an unfolded and stretched state. [Figure 3] FIG. 3 is a schematic cross-sectional view taken along line CC in FIG. 2. [Figure 4] FIG. 3 is a schematic cross-sectional view of the absorbent body taken along the line CL-CL in FIG. 2. [Figure 5] 10 is a diagram illustrating the arrangement of the crotch elastic members 40. FIG. [Figure 6] FIG. 10 is an explanatory diagram of a lifting test. [Figure 7] FIG. 10 is an explanatory diagram of a lifting test. [Figure 8] FIG. 10 is an explanatory diagram of a lifting test. [Figure 9] FIG. 1 is an explanatory diagram of a pre-absorption lifting test. [Figure 10] FIG. 10 is a diagram showing the state in which the waist portion is stretched after the lifting test. [Figure 11] FIG. 10 is an explanatory diagram of a modified diaper 1. [Figure 12] FIG. 2 is an explanatory diagram of a compression unit 60. [Figure 13] 13A and 13B are explanatory diagrams of the compression unit 60. FIG. [Figure 14] 14A and 14B are schematic cross-sectional views of the absorbent core 11. 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 is an absorbent article having an absorbent core, which in an unfolded and stretched state has longitudinal, left-right, and thickness directions that intersect with one another, and which has crotch elastic members that stretch in the longitudinal direction, and at least a portion of the crotch elastic members is provided in the left-right central portion of the crotch portion, which is the central region when the absorbent article is divided into thirds equal parts in the longitudinal direction, and at the central position of the absorbent article in the longitudinal direction, the absorbent core is single-layered, and when a lifting test is conducted in which a liquid is dripped from the left-right central position in the longitudinally folded position, and then the waist side end and both left-right ends of the absorbent article in the longitudinally folded state are grasped and lifted, the left-right central portion of the lower end of the absorbent article forms a convex shape facing upward.

[0010] According to the first aspect, the crotch elastic members allow the absorbent core to easily fit closely to the wearer's crotch area, thereby preventing leakage of body waste. Furthermore, because the absorbent core is single-layered at the position that contacts the wearer's crotch area, the wearer is less likely to experience discomfort due to stiffness. Furthermore, the suspension test takes into consideration the deformation of the absorbent core after excretion, and the absorbent core is more likely to maintain its close fit to the wearer's crotch area even after excretion. Therefore, discomfort caused by a decrease in fit to the wearer's crotch area (sagging of the absorbent article) can be reduced.

[0011] Aspect 2 is an absorbent article according to aspect 1, wherein, in an unfolded and stretched state, the length of the stretchable portion of the crotch elastic member located on the ventral side of the center position of the absorbent article in the longitudinal direction is longer than the length of the stretchable portion of the crotch elastic member located on the dorsal side of the center position.

[0012] According to the second aspect, the crotch elastic members are easily positioned in correspondence with the wearer's urethral opening, and the crotch elastic members can directly push the absorbent core up against the urethral opening, which makes it easier for the absorbent core to adhere to the urethral opening and further reduces leakage of excretory fluid.

[0013] Aspect 3 is the absorbent article according to aspect 1 or 2, wherein in the unfolded and stretched state, the stretchable portion of the crotch elastic member is positioned across the center position of the absorbent article in the longitudinal direction.

[0014] According to the third aspect, the crotch elastic members can directly push up the absorbent core at the longitudinal center position, thereby making the center portion of the lower end of the absorbent article in the left-right direction convex upward in a lifting test.

[0015] Aspect 4 is an absorbent article according to any one of aspects 1 to 3, which has a transverse elastic member that stretches in the left-right direction, and when the area defined by the crotch elastic member in the unfolded and stretched state is defined as the crotch elastic region, when the absorbent article is viewed in the thickness direction, the crotch elastic region does not overlap with the stretchable portion of the transverse elastic member.

[0016] According to the fourth aspect, it is possible to prevent the longitudinal stretching force of the crotch elastic members from being inhibited by the lateral stretching force of the lateral elastic members, and therefore, even after excretion, the crotch elastic members can push up the absorbent core, and in a lifting test, the central portion in the left-right direction of the lower end of the absorbent article can be made to have an upwardly convex shape.

[0017] Aspect 5 is an absorbent article according to any one of aspects 1 to 4, which has a plurality of continuous elastic members that are stretchable in the left-right direction and that are continuous at positions that overlap with the absorbent core in the left-right direction, and in an unfolded and stretched state, when the continuous elastic member closest to the crotch elastic member on the ventral side in the longitudinal direction is designated as a ventral continuous elastic member and the continuous elastic member closest to the crotch elastic member on the back side in the longitudinal direction is designated as a back continuous elastic member, the length from the ventral end of the stretchable portion of the crotch elastic member to the ventral continuous elastic member in the longitudinal direction is shorter than the length from the back end of the stretchable portion of the crotch elastic member to the back continuous elastic member.

[0018] According to the fifth aspect, the length of the region on the ventral side of the absorbent article where the force of the elastic members does not directly act on the absorbent core is shortened, which makes it easier for the absorbent core to fit closely to the wearer's urethral opening located on the ventral side, thereby further suppressing leakage of excrement.

[0019] Aspect 6 is an absorbent article according to any one of aspects 1 to 5, which has a continuous elastic member that stretches in the left-right direction and is continuous at a position that overlaps with the absorbent core in the left-right direction, and the crotch elastic member is a plurality of thread-like elastic members, and when, in an unfolded and stretched state, the continuous elastic member closest to the crotch elastic member on the back side in the longitudinal direction is the back-side continuous elastic member, the force required to stretch the stretchable portion of the back-side continuous elastic member to a predetermined length in the left-right direction is smaller than the average value of the force required to stretch each of the plurality of thread-like elastic members to the predetermined length in the longitudinal direction.

[0020] According to aspect 6, the relatively weak elastic force of the back-side continuous elastic member forms a space between the wearer's buttocks and the absorbent core, which can accommodate feces or temporarily accommodate a large amount of urine excreted, thereby preventing leakage of body waste. On the other hand, the relatively strong elastic force of the crotch elastic member allows the central part in the left-right direction of the lower end of the absorbent article to be formed into a convex shape facing upward in a lifting test.

[0021] A seventh aspect is the absorbent article according to any one of the first to sixth aspects, wherein there is no low basis weight region in which the absorbent core has a lower basis weight than the surrounding area at the central position of the absorbent article in the longitudinal direction.

[0022] According to the seventh aspect, even if the absorbent core is a single layer at the center position in the longitudinal direction, it is possible to ensure the absorption amount of excrement and suppress leakage of excrement. In addition, it is possible to reduce the risk of unintended deformation during a lifting test, and it is possible to make the center portion of the lower end of the absorbent article convex upward.

[0023] Aspect 8 is an absorbent article according to any one of aspects 1 to 7, which has a compressed portion in which the absorbent core is compressed in the thickness direction, and the crotch elastic members are a plurality of thread-like elastic members, and the compressed portion is arranged between a plurality of the thread-like elastic members arranged in the left-right direction.

[0024] According to the eighth aspect, the rigidity of the absorbent core between the crotch elastic members (thread-like elastic members) is increased. Therefore, even after excretion, the absorbent core between the crotch elastic members is easily pushed up in conjunction with the absorbent core that is directly pushed up by the crotch elastic members. Therefore, the absorbent core can be closely fitted to the crotch area of ​​the wearer, reducing discomfort to the wearer due to poor fit.

[0025] Aspect 9 is an absorbent article according to any one of aspects 1 to 8, which has a compressed portion in which the absorbent core is compressed in the thickness direction, and in an unfolded and stretched state, when the area defined by the crotch elastic member is defined as the crotch elastic region, the compressed portion has at least a portion of an inclined compressed portion in the crotch elastic region that is inclined relative to the longitudinal direction and the left-right direction.

[0026] According to the ninth aspect, the obliquely compressed portions serve as folding start points, making it easier for the absorbent core overlapping the crotch elastic region to deform. As a result, in a lifting test, the left-right central portion of the lower end of the absorbent article can be made to have an upwardly convex shape.

[0027] Aspect 10 is an absorbent article described in aspect 9, wherein the inclined compression portion has a plurality of first inclined portions along a first inclined direction and a plurality of second inclined portions along a second inclined direction that intersects the first inclined direction, the plurality of first inclined portions are arranged at intervals in the second inclined direction, and the plurality of second inclined portions are arranged at intervals in the first inclined direction, and in the unfolded and stretched state, the left-right length of the area partitioned by the plurality of first inclined portions and the plurality of second inclined portions is shorter than the left-right length of the crotch elastic region.

[0028] According to the tenth aspect, the region defined by the plurality of first inclined portions and the plurality of second inclined portions is easily accommodated within the portion of the absorbent core overlapping the crotch elastic region. Therefore, the inclined compressed portions that define the region become folding start points, and the absorbent core overlapping the crotch elastic region is easily deformed. Therefore, in a lifting test, the center portion in the left-right direction of the lower end of the absorbent article can be made to have an upwardly convex shape.

[0029] Aspect 11 is an absorbent article described in any of aspects 1 to 10, wherein when a pre-absorption lifting test is conducted in which the absorbent article, which is in a dry state and folded in half in the longitudinal direction, is lifted by grasping the waist side end and both left and right end portions, the left and right central portion of the lower end of the absorbent article forms a convex shape facing upward, and the height of the convex shape in the lifting test is greater than the height of the convex shape in the pre-absorption lifting test.

[0030] According to Aspect 11, the absorbent core adheres closely to the wearer's crotch area before excretion, thereby preventing leakage during the first excretion. Even after excretion, the center of the absorbent core in the left-right direction remains in close contact with the wearer's crotch area, thereby reducing discomfort to the wearer.

[0031] Aspect 12 is an absorbent article according to any one of aspects 1 to 11, which is a pants-type absorbent article having a waist elastic member that stretches in the left-right direction, and when the lifting test is performed, the waist side end of the absorbent article forms a concave shape that curves downward, and the height of the convex shape is smaller than the vertical length from an imaginary line connecting the left and right ends of the waist side end of the absorbent article to the center of the waist side end in the left-right direction.

[0032] According to aspect 12, after excretion, the central portion in the left-right direction of the lower end of the absorbent article forms a convex shape, but its height is moderately reduced. Therefore, after excretion, the absorbent core adheres closely to the crotch area of ​​the wearer, but is prevented from pressing too strongly against the crotch area of ​​the wearer, thereby reducing discomfort to the wearer.

[0033] Aspect 13 is an absorbent article described in any of aspects 1 to 12, which is a pants-type absorbent article having a waist elastic member that stretches in the left-right direction, and after the lifting test, when the gripping position of the waist end of the absorbent article is widened to a length that is 80% of the length when the waist end of the absorbent article is most stretched in the left-right direction, the vertical length from an imaginary line connecting the left and right ends of the waist end of the absorbent article to the center of the waist end in the left-right direction is smaller than the height of the convex shape.

[0034] According to aspect 13, when the waist portion of the absorbent article is stretched and worn, the difference in vertical dimension between the left and right side portions and the center portion at the waist-side end is small. Therefore, the absorbent article can evenly cover the entire waist of the wearer. Meanwhile, because the center portion at the left and right end of the absorbent article has an upwardly convex shape, the absorbent core can fit closely to the crotch area of ​​the wearer even after excretion, reducing discomfort to the wearer.

[0035] Aspect 14 is an absorbent article according to any one of aspects 1 to 13, comprising an absorbent main body having the absorbent core and an outer covering member, the outer covering member having a pair of waistband portions and a crotch portion connecting the pair of waistband portions.

[0036] According to the fourteenth aspect, the absorbent core, which has gained weight after excretion, is pulled up by the crotch portion of the outer member that continues from the waistband portion, thereby reducing discomfort to the wearer caused by the sagging of the absorbent core.

[0037] === Implementation form === The absorbent article according to the embodiment of the present invention will be described below using an example of a pants-type disposable diaper for adults (hereinafter also referred to as "diaper 1"). However, the absorbent article according to the present invention is not limited to the above and can also be used as a tape-type disposable diaper, sanitary shorts, etc. Furthermore, the wearer may be a living organism such as an infant or an animal.

[0038] <<Basic structure of pants-type disposable diaper 1>> Fig. 1 is a schematic front view of a pants-type disposable diaper 1. Fig. 2 is a schematic plan view of the diaper 1 in an unfolded and stretched state. Fig. 3 is a schematic cross-sectional view taken along line CC in Fig. 2. Fig. 4 is a schematic cross-sectional view of the absorbent main body 10 taken along line CL-CL in Fig. 2. Here, the "unfolded state" of the diaper 1 refers to a state in which the waist seam 2 (described later) is untied, the diaper 1 is unfolded in the longitudinal direction, and the diaper 1 is unfolded in a plane.

[0039] In the pants-type state shown in FIG. 1, the diaper 1 has a vertical direction, a horizontal direction, and a front-to-back direction, which intersect with one another, and is formed with a waist opening BH and a pair of leg openings LH. In the unfolded state shown in FIG. 2, the diaper 1 has a longitudinal direction, a horizontal direction, and a thickness direction, which intersect with one another. The longitudinal direction is the direction along the vertical direction in the pants-type state. The thickness direction is the direction in which the components constituting the diaper 1 are layered (see FIG. 4). In the vertical direction, the waist opening BH side is the upper side, and the crotch side is the lower side. In the front-to-back direction, the side facing the wearer's stomach is the front side, and the side facing the wearer's back is the rear side. In the thickness direction, the side in contact with the wearer's body (skin) is the skin side, and the opposite side is the non-skin side.

[0040] Furthermore, the "stretched state" of the diaper 1 refers to a state in which the entire diaper 1 is stretched without wrinkles by stretching each elastic member of the diaper 1 (for example, the waist elastic members 24, 25 and the leak-proof wall elastic member 51, which will be described later), specifically, a state in which the dimensions of each material constituting the diaper 1 (for example, the top sheet 12 and the inner layer sheet 23, which will be described later) are stretched to the same dimensions as or close to the dimensions of the individual member.

[0041] As shown in Fig. 3, the diaper 1 has an absorbent main body 10 and an exterior member 20 arranged on the non-skin side of the absorbent main body 10. The absorbent main body 10 and the exterior member 20 are joined with an adhesive (not shown). Cover sheets 31, 32 may be provided to cover both longitudinal ends of the absorbent main body 10 from the skin side. This can prevent the edges of the absorbent main body 10 from digging into the wearer's body and prevent the absorbent main body 10 from opening open.

[0042] In this specification, as shown in Fig. 2, when the diaper 1 is in an unfolded and stretched state, the diaper 1 is divided into three equal parts in the longitudinal direction, and the ventral region is referred to as the "ventral portion 1A," the central region is referred to as the "crotch portion 1B," and the dorsal region is referred to as the "dorsal portion 1C." The diaper 1 in an unfolded state is folded in half at the longitudinal central position CL, and the left and right side portions of the outer member 20 of the ventral portion 1A and the outer member 20 of the dorsal portion 1C are joined together to form the pants-type diaper 1 shown in Fig. 1. Examples of joining methods for the waist seam 2 include welding and joining with an adhesive.

[0043] 4, the absorbent body 10 includes an absorbent core 11 that absorbs excrement, a liquid-permeable top sheet 12 (e.g., nonwoven fabric) arranged on the skin side of the absorbent core 11 in the thickness direction, a liquid-impermeable back sheet 13 (e.g., a resin film such as polyethylene or polypropylene) arranged on the non-skin side of the absorbent core 11 in the thickness direction, a liquid-permeable intermediate sheet 15 (e.g., nonwoven fabric) arranged between the top sheet 12 and the absorbent core 11, a pair of side sheets 16, and an elastic member cover sheet 17. The elastic member cover sheet 17 is a sheet member that covers the non-skin side of the crotch elastic members 40 (described in detail later) that stretch in the longitudinal direction.

[0044] The absorbent core 11 absorbs and retains excreted liquids such as urine. The surface of the absorbent core 11 may be covered with a liquid-permeable core wrap sheet 18 (e.g., tissue paper). An example of the absorbent core 11 is one in which liquid-absorbent fibers such as pulp containing superabsorbent polymer (SAP) are molded into a predetermined shape. The absorbent core 11 of this embodiment has a shape in which the center portion in the longitudinal direction is narrowed inward in the left-right direction, but the planar shape of the absorbent core 11 is not particularly limited.

[0045] A pair of leakage preventing walls 50 is provided along the longitudinal direction on both left and right sides of the absorbent body 10. As shown in Figure 4, portions of the side sheets 16 extending from both left and right sides of the non-skin side of the back sheet 13 are folded at multiple locations and provided on both left and right sides of the skin side of the top sheet 12 to form the leakage preventing walls 50. Leak preventing wall elastic members 51 (e.g., rubber thread) are attached to the leakage preventing walls 50 in a stretched state along the longitudinal direction. The stretchability of the leakage preventing wall elastic members 51 allows the leakage preventing walls 50 to stand up towards the skin side of the wearer and block bodily waste.

[0046] The outer covering member 20 is a sheet member having a shape in which the longitudinal center portion is narrowed inward in the left-right direction. As shown in Fig. 3, the outer covering member 20 has a ventral outer layer sheet 21, a dorsal outer layer sheet 22, an inner layer sheet 23, waist elastic members 24 and 25, and a buttocks elastic member 26.

[0047] The ventral outer layer sheet 21, the back outer layer sheet 22, and the inner layer sheet 23 can be exemplified by flexible sheet members such as nonwoven fabrics. The inner layer sheet 23 forms the outer shape of the exterior member 20 and is a sheet member that is continuous from the ventral portion 1A through the crotch portion 1B to the back portion 1C. The ventral outer layer sheet 21 is disposed closer to the skin than the inner layer sheet 23 and in part of the ventral portion 1A. The ventral outer layer sheet 21 overlaps with the waistline joint 2 in the longitudinal direction and has the same longitudinal length as the waistline joint 2. The back outer layer sheet 22 is disposed closer to the skin than the inner layer sheet 23 and in part of the back portion 1C and the crotch portion 1B. The back outer layer sheet 21 overlaps with the waistline joint 2 in the longitudinal direction and extends further toward the crotch than the waistline joint 2. In the flattened diaper 1, the ventral outer sheet 21 and the dorsal outer sheet 22 are spaced apart in the longitudinal direction, with the inner sheet 23 exposed to the outside as the non-skin side of the diaper 1 between them.

[0048] The waist elastic members 24, 25 and the buttocks elastic members 26 are elastic members that stretch in the left-right direction, and can be exemplified by thread-like elastic members such as rubber thread. As shown in FIG. 2, the waist elastic members 24, 25 overlap the waist joint 2 in the longitudinal direction. In the following description, the waist elastic member located in the ventral portion 1A will also be referred to as the ventral waist elastic member 24, and the waist elastic member 25 located in the back portion 1C will also be referred to as the back waist elastic member 25. The buttocks elastic member 26 is located on the crotch side in the longitudinal direction (lower in the up-down direction) than the waist joint 2. In this embodiment, there are two buttocks elastic members 26, but this number is not particularly limited.

[0049] The waist elastic members 24, 25 and buttocks elastic members 26 are arranged side by side in the vertical direction in the pants-shaped state between the inner layer sheet 23 and the ventral-side outer layer sheet 21 or the dorsal-side outer layer sheet 22, and are fixed in a stretched state in the horizontal direction, so that the outer member 20 fits snugly around the waist and buttocks of the wearer.

[0050] <<Crotch elastic member 40>> 5 is a diagram illustrating the arrangement of the crotch elastic members 40 and is a partial schematic plan view of the diaper 1 in an unfolded and stretched state. The diaper 1 has "crotch elastic members 40" that stretch in the longitudinal direction. At least a portion of the crotch elastic members 40 is provided in the left-right central portion of the "crotch portion 1B," which is the central region when the diaper 1 in an unfolded and stretched state is divided into thirds in the longitudinal direction.

[0051] The diaper 1 of this embodiment has a plurality of thread-like elastic members (e.g., rubber thread) as the crotch elastic members 40. As shown in Fig. 4, the plurality of crotch elastic members 40 (five thread-like elastic members) are arranged side by side at intervals in the left-right direction between the back sheet 13 and the elastic member cover sheet 17 in the thickness direction. Each crotch elastic member 40 is attached in a stretched state along the longitudinal direction. Note that the drawings show only the stretchable portions of the crotch elastic members 40, i.e., the portions of the crotch elastic members 40 that exhibit stretchability.

[0052] The crotch elastic members 40, located in the lateral center of the crotch portion 1B, overlap the absorbent core 11 in the thickness direction. The crotch elastic members 40 are bonded to the absorbent core 11 via the backsheet 13 with an adhesive or the like. Therefore, when the diaper 1 is worn, the crotch elastic members 40 contract in the longitudinal direction, and the absorbent core 11 is easily deformed to be pushed up toward the wearer's skin and fit closely to the wearer's crotch portion. Specifically, the absorbent core 11 is easily bent at the boundary between the lateral center where the crotch elastic members 40 are located and the outer side portions of the absorbent core 11 in the lateral direction. In other words, the lateral center of the absorbent core 11 is easily deformed into a convex shape toward the upper side (the wearer's crotch portion). This reduces the likelihood of a gap forming between the wearer's crotch portion and the absorbent core 11, thereby preventing urine and other excrement from leaking out of the diaper 1 along the wearer's skin.

[0053] In this specification, the region defined by the crotch elastic members 40 is also referred to as the "crotch elastic region ER." Specifically, when the crotch elastic members 40 are multiple thread-like elastic members arranged at intervals in the left-right direction, the following definition applies: In the crotch section 1B, the region between the leftmost crotch elastic member 40a (thread-like elastic member) and the rightmost crotch elastic member 40b (thread-like elastic member) is defined as the region enclosed by an imaginary line connecting the longitudinal ventral ends of the crotch elastic members 40 (stretchable portions) arranged in the left-right direction and an imaginary line connecting the longitudinal dorsal ends of the crotch elastic members 40 (stretchable portions). The crotch elastic members 40 are not limited to multiple thread-like elastic members, but may also be a stretchable sheet (e.g., a stretchable nonwoven fabric or a stretchable film) or a flat rubber band (a band-like rubber band). In this case, the region where the stretchable sheet is arranged is defined as the "crotch elastic region ER." When multiple strip-shaped stretch sheets or flat rubber bands are arranged at intervals in the left-right direction, the same applies as in the case of thread-like elastic members. In other words, the region between the rightmost crotch elastic member 40 (strip-shaped stretch sheet or flat rubber band) and the leftmost crotch elastic member 40 is called the crotch elastic region ER.

[0054] Furthermore, it is sufficient that at least a portion of the crotch elastic member 40 is located in the crotch portion 1B, and it may extend to the abdominal portion 1A, may extend to the dorsal portion 1C, or may be contained within the crotch portion 1B. Furthermore, the crotch elastic member 40 being located in the left-right central portion of the crotch portion 1B means that at least a portion of the crotch elastic member 40 (crotch elastic region ER) is located in the central region CR when the absorbent core 11 is divided into thirds at its maximum width, as shown in Fig. 2.

[0055] <<Lifting test>> 6, 7, and 8 are explanatory diagrams of the lifting test. In the diaper 1 of this embodiment, as shown in Fig. 4, the absorbent core 11 is a single layer at the longitudinal center position CL in the unfolded and stretched state. The longitudinal center position CL of the diaper 1 is the position that abuts against the wearer's crotch region. Therefore, the wearer is less likely to experience discomfort (foreign body sensation) due to stiffness compared to when multiple absorbent cores are stacked in the thickness direction at the longitudinal center position CL.

[0056] However, it is sufficient that the absorbent core 11 has a single-layer structure at least at the center position CL in the longitudinal direction. Therefore, a multi-layer structure in which multiple absorbent cores 11 are stacked at positions away from the center position CL in the longitudinal direction may be used. For example, a so-called SAP sheet, which is a hydrophilic sheet with an SAP layer attached, may be stacked on an absorbent core made of pulp.

[0057] Furthermore, when a liquid is dripped onto the diaper 1 of this embodiment at the lateral center position at the longitudinal folded position FL, which is set as the drip position P (FIG. 7), and then the diaper 1 is lifted by grasping the waist-side end and both lateral ends of the diaper 1 folded in half longitudinally, the lateral center portion 1Elc of the lower end 1El of the diaper 1 forms a convex shape upward. The amount of liquid (300 ml) is an amount that is estimated to be the amount of urine excreted in one or two urinations. Furthermore, the longitudinally folded state refers to a state in which the diaper 1 is folded in half with the skin-side surface facing inward.

[0058] Generally, when the absorbent core absorbs excretory fluid, the entire lower edge of the diaper sags under its own weight when worn (folded in half lengthwise). Specifically, the entire lower edge of the region where the absorbent core is located becomes substantially linear or forms a downward convex shape from the left and right sides to the center. This reduces the adhesion of the absorbent core to the wearer's crotch area, making the wearer more likely to experience discomfort.

[0059] In contrast, in the diaper 1 of this embodiment, after absorbing excrement, the lateral central portion 1Elc of the lower end 1El of the diaper 1 when worn (folded in half longitudinally) is pushed up in the vertical direction of the diaper 1 compared to the side portions. In other words, even after one or two excretions, the absorbent core 11 remains in close contact with the wearer's crotch region. In this way, the diaper 1 of this embodiment, which takes into account deformation of the absorbent core 11 after excretion using a lifting test, can reduce discomfort to the wearer caused by sagging of the diaper 1. Furthermore, because gaps are unlikely to form between the wearer's crotch region and the absorbent core 11, the absorbent core 11 can receive and absorb excrement even after repeated excretions, preventing the excrement from leaking along the wearer's skin.

[0060] As described above, the diaper 1 of this embodiment has the crotch elastic members 40. Therefore, due to the stretching force of the crotch elastic members 40, even after absorbing excrement, the central portion 1Elc in the left-right direction of the bottom end 1El of the diaper 1 in the folded state is pushed up toward the skin, forming an upwardly convex shape.

[0061] In addition, in the diaper 1 of this embodiment, the absorbent core 11 is a single layer at the longitudinal center position CL (a position roughly corresponding to the bottom end 1El in the folded state). If the absorbent core had a multi-layer structure at the longitudinal center position and the layers had different widths, the absorbent core would be prone to folding at the position where the number of layers changes, which could result in unintended deformation. In contrast, in the diaper 1 of this embodiment, there is no folding start point due to a change in the number of layers of the absorbent core 11 at the longitudinal center position CL, thereby reducing the risk of unintended deformation. Therefore, the lateral center portion 1Elc of the bottom end 1El of the diaper 1 in the folded state can more reliably form a convex shape facing upward.

[0062] The method of the "lifting test" will now be described in detail. (1) Remove the diaper 1 to be measured from the package. Leave the diaper 1 in its packaged state in a testing room (room temperature 20°C, humidity approximately 60%) for 24 hours. If the diaper 1 is folded inward on both sides of the waistband or folded in half lengthwise, for example, leave it in the folded state for packaging.

[0063] (2) Thereafter, as shown in Fig. 6, the waist portion of the diaper 1 is attached to a cylindrical jig (hollow cylindrical jig) 52. In the case of a pants-type diaper 1, the diaper is attached to the cylindrical jig 52 with the waist seam 2 already joined. In the case of a tape-type diaper (not shown), the waist portion of the tape-type diaper is wrapped around the cylindrical jig 52, and the ventral waist portion and the dorsal waist portion are joined together with fastening tape. In the case of an absorbent article intended for an adult wearer, the diameter (outer diameter) D52 of the cylindrical jig 52 is set to 210 mm. This length (=circumference / pi) is based on the circumference when the diaper 1 of this embodiment is stretched to approximately 63% of its maximum stretched length (when the circumference (inner circumference) of the waist opening BH is 100%). In the case of an absorbent article intended for an infant wearer, the diameter (outer diameter) D52 of the cylindrical jig 52 is set to 165 mm. The thickness of the cylindrical jig 52 is set to approximately 5 mm. However, the inner diameter of the cylindrical jig 52 need only be large enough to allow a burette to be inserted and artificial urine to be dripped into it. The upper end (waist-side end) 1Eu of the diaper 1 is set in a straight line with the cylindrical jig 52. If necessary, the diaper 1 may be fixed to the cylindrical jig 52 using tape 53. The cylindrical jig 52 is set so that its lower end 52L coincides with the upper end 11a (longitudinal end) of the absorbent core 11. If the length from the upper end 1Eu of the diaper 1 to the upper end 11a of the absorbent core 11 differs between the front and rear, the diaper 1 is set in the cylindrical jig 52 based on the shorter end (the upper end 11a of the absorbent core 11 located closer to the waist). Finally, with the diaper 1 placed on the cylindrical jig 52, it is confirmed that the absorbent core 11 (or the crotch elastic members 40, if any) is not stretched (is in its natural state). If the absorbent core 11 or the crotch elastic members 40 are stretched, the diameter D52 of the cylindrical jig 52 is adjusted, a new diaper 1 is prepared, and the test is repeated. Furthermore, if the intended wearer is neither an adult nor an infant, the diameter D52 of the cylindrical jig 52 is determined based on the expected waist circumference of the intended wearer (for example, in the case of a pants-type absorbent article, a cylindrical jig 52 is prepared based on the circumference when the waist portion is stretched by approximately 60% to 65% of its maximum stretch).

[0064] (3) Next, as shown in Figure 7, the drip position P (the center position in the left-right direction at the folded position FL in the longitudinal direction) is identified by viewing the skin-side surface of the diaper 1 from above the cylindrical jig 52. Generally, pants-type and tape-type absorbent articles are folded in half at the center position CL in the longitudinal direction and packaged. In this case, the center position in the left-right direction at the folded position FL when packaged is identified as the drip position P. In other cases, the center position in the longitudinal direction and the left-right direction of the diaper 1 in the unfolded and stretched state is identified as the drip position.

[0065] (4) Next, artificial urine (300 ml in total) is dripped onto drip position P. The artificial urine is dripped while the bottom end of the diaper 1 is floating above the workbench 50. The artificial urine was prepared by dissolving 200 g of urea, 80 g of sodium chloride, 8 g of magnesium sulfate, 3 g of calcium chloride, and approximately 1 g of blue No. 1 dye in 10 L of ion-exchanged water. Specifically, 150 ml of artificial urine is dripped at a constant rate (150 ml / 15 seconds) using a burette from 30 mm above drip position P (the skin side of the diaper 1). After 3 minutes, another 150 ml of artificial urine is dripped at a constant rate (150 ml / 15 seconds) in the same manner.

[0066] (5) Next, after three minutes have passed since the artificial urine dripping was completed, the diaper 1 is removed from the cylindrical jig 52. Then, two clips 51 (e.g., eye clips) with a gripping width W51 of 65 mm are prepared. Also, a pair of horizontal support rods 54 extending horizontally from a vertical support rod (not shown) are prepared. In the case of a pants-type diaper 1 (see Figure 1), marks M are marked on the inside of both left and right ends 1Eus, 1Eus of the waist end (upper end) 1Eu of the diaper 1 in its natural state, over the length (65 mm) of the gripping width W51 of the clip 51. Mark M is marked at a position h51 (= 15 mm) downward from the waist end 1Eu of the diaper 1. In other words, mark M is marked along the left and right direction of the diaper 1 from the outer edge of the waist seam 2, which is located h51 (= 15 mm) below the left and right ends 1Eus, 1Eus of the waist end 1Eu of the diaper 1. In the case of tape-type diapers, the position of the left-right edge of the upper end of the absorbent core in the abdominal side is used as the reference point. Marks are made from the left-right edge of the upper end of the absorbent core outward in the left-right direction, over the length (65 mm) of the gripping width W51 of the clip 51. Mark M is made along the left-right direction of the tape-type diaper, starting from a position h51 (= 15 mm) below the waist side edge of the folded tape-type diaper. In addition, the length W1 from the left end of the mark M on the left side of the diaper 1 in its natural state to the right end of the mark M on the right side is measured using a ruler or the like. Then, the lower end of the clip 51 is aligned with the mark M, and the clip 51 grips both left and right ends of the waist end (upper end) of the diaper 1 folded in half in the longitudinal direction. Specifically, the outer edge of the mark M is aligned with the outer edge of the lower end of the clip 51 in the left and right direction of the diaper 1. The clip 51 clamps the entire folded diaper 1 (both the ventral side portion 1A and the dorsal side portion 1C). At this time, the clip 51 clamps not only the diaper 1 but also the horizontal support bar 54 on the dorsal side of the diaper 1. If necessary, an anti-slip member may be provided on the horizontal support bar 54 to prevent the clip 51 from shifting position relative to the diaper 1.

[0067] (6) Then, as shown in FIG. 8, the clips 51 are lifted vertically so that the left-right distance W1 between the left and right clips 51 (lower ends) is maintained at the same distance W1 when the diaper 1 is in its natural state. In other words, the diaper 1 is lifted while the waistband is not stretched in the left-right direction (in its natural state). The diaper 1 is lifted until the vertical height of the left and right clips 51 is constant (horizontal) and the bottom end 1El of the folded diaper 1 contacts the test stand 50 (a horizontal surface). The diaper 1 is then visually inspected from the abdominal portion 1A. Preferably, a still image of the diaper 1 is taken using a digital camera. It is then confirmed that the left-right central portion 1Elc of the bottom end 1El (more specifically, the bottom end of the absorbent core 11) of the diaper 1 is positioned higher in the vertical direction than the left-right side portions. If this is confirmed, it is assumed that the central portion 1Elc in the left-right direction of the lower end 1El of the diaper 1 forms an upwardly convex shape.

[0068] A pants-type diaper 1 according to the present embodiment (the diaper 1 having the configuration shown in Figs. 1 to 4) was actually prepared and subjected to a lifting test. Specifically, in the unfolded and stretched state of the diaper 1, the absorbent core 11 had a longitudinal length of 480 mm, a maximum width of 200 mm, and a basis weight of 564 g / m 2 The test was conducted using a diaper 1 having crotch elastic members 40 with a length of 160 mm, an extension ratio of 2.2, a thickness of 780 dtext, and a lateral pitch of 8 mm. The extension ratio is the value obtained by dividing the length of the crotch elastic members 40 at their maximum extension (the extended state of the diaper 1) by the length of the diaper 1 in an unloaded state (the natural state of the diaper 1). As a result, in the diaper 1 of this embodiment, the lateral central portion 1Elc at the bottom end 1El in the folded state was convex upward.

[0069] Therefore, in the diaper 1 of this embodiment, the crotch elastic members 40 allow the absorbent core 11 to fit closely to the crotch area of ​​the wearer, thereby preventing leakage of excrement. This also reduces discomfort caused by stiffness of the absorbent core 11 in the crotch area of ​​the wearer. Furthermore, the diaper 1 of this embodiment takes into consideration deformation of the absorbent core 11 after excretion, thereby preventing discomfort caused by a decrease in fit to the crotch area after excretion.

[0070] FIG. 9 is an explanatory diagram of a pre-absorption lifting test. In the "pre-absorption lifting test," in which a dry diaper 1 folded in half longitudinally is gripped and lifted by the waist end and both lateral ends, it is preferable that the lateral central portion 1Elc of the lower end 1El of the diaper 1 has an upwardly convex shape, as shown in FIG. 9. This allows the absorbent core 11 to fit closely to the wearer's crotch area even before excretion. Therefore, during the first excretion, the absorbent core 11 can receive and absorb excreted liquid and prevent the excreted liquid from leaking along the wearer's skin.

[0071] Furthermore, it is preferable that the height H1 of the convex shape of the left-right central portion 1Elc of the lower end 1El of the diaper 1 when the aforementioned lifting test (Figure 8) is performed is greater than the height H2 of the convex shape of the left-right central portion 1Elc of the lower end 1El of the diaper 1 when the pre-absorption lifting test (Figure 9) is performed (H1>H2).

[0072] As described above, after absorbing excrement, even if both left and right side portions of the absorbent core 11 sag due to the weight of the excrement, it is preferable that the left and right central portion be prevented from sagging and be kept pushed up toward the skin by the crotch elastic members 40. This reduces discomfort to the wearer caused by the sagging of the absorbent core 11. Furthermore, even in the case of repeated excrement, gaps are unlikely to form between the crotch portion of the wearer and the absorbent core 11, preventing excrement from leaking along the wearer's skin.

[0073] The heights H1 and H2 of the convex shape may be compared based on image data captured with a digital camera after the lifting test and the pre-absorption lifting test. Specifically, the position of the uppermost end 1Elu of the diaper 1's left-right central portion 1Elc is identified in the image data, and the height from the test stand 50 is determined. However, this is not limited to the above, and for example, the height may be measured directly from the actually lifted diaper 1 using a ruler. The height H3 of the concave shape (see FIG. 8) and the height H4 from the virtual line VL2 to the waist end 1Eu (see FIG. 10), which will be described below, can also be determined in a similar manner.

[0074] The method for the "pre-absorption lifting test" will now be described. This test is identical to the lifting test, except for the step of dripping artificial urine onto the diaper 1. Briefly, the diaper 1 to be measured is first removed from its package. The diaper 1 is then left in its package in a test room (room temperature 20°C, humidity 60%) for 24 hours. Next, the diaper 1 is unfolded as needed, and a mark M is marked on the diaper 1 at the position where it will be gripped by the clips 51. The distance W1 between the left and right marks M is also measured. The lower ends of the clips 51 are then aligned with the mark M, and both left and right ends of the waist-side end (upper end) of the diaper 1 folded in half longitudinally are gripped by the clips 51. The clips 51 are then lifted vertically until the heights of the left and right clips 51 are uniform (horizontal) and the lowest end 1E1 of the folded diaper 1 touches the test stand 50 (horizontal surface). At this time, the diaper 1 is lifted up in a natural state where the waist portion is not stretched in the left-right direction (the distance between the left and right clips 51 (lower ends) is maintained at W1), and the diaper 1 is observed from the abdominal portion 1A.

[0075] Also, when the pants-type diaper 1 is subjected to a suspension test (see FIG. 8), when the end 1Eu on the waist side of the diaper 1 forms a concave shape that curves downward, the following may be satisfied. In the suspension test, it is preferable that the height H1 of the convex shape at the lower end of the diaper 1 is smaller than the height H3 of the concave shape at the end 1Eu on the waist side of the diaper 1 (H1 < H3). Specifically, it is preferable that the height H1 of the convex shape at the central portion 1Elc in the left-right direction of the lower end 1El of the diaper 1 is smaller than the vertical length H3 from the virtual line VL1 connecting the left and right ends 1Eus, 1Eus at the end 1Eu on the waist side of the diaper 1 to the central portion 1Euc in the left-right direction of the end 1Eu on the waist side. The central portion 1Euc in the left-right direction of the end 1Eu on the waist side of the diaper 1 is set at a position corresponding to the center in the left-right direction of the virtual line VL1.

[0076] According to the above, after excretion, the central portion 1Elc in the left-right direction of the lower end of the diaper 1 forms a convex shape, and its height is appropriately suppressed. Therefore, while the absorbent core 11 adheres to the wearer's crotch, it is possible to prevent the pressure on the wearer's crotch from becoming too strong. Therefore, it is possible to reduce the discomfort of the wearer while suppressing the leakage of excreted fluid.

[0077] FIG. 10 is a view showing a state where the body circumference portion is extended after the suspension test. After the suspension test (FIG. 8) is performed on the pants-type diaper 1, when the length W2 (= Wmax × 80%) of 80% of the length Wmax (see FIG. 2) when the end 1Eu on the waist side of the diaper 1 is most extended in the left-right direction, the following may be satisfied in the state where the gripping position of the end on the waist side of the diaper 1 is widened. Specifically, the length in the left-right direction from the left end of the left clip 51 (lower end) for suspending the diaper 1 to the right end of the right clip 51 (lower end) is widened to the length W2 of 80%.

[0078] In the above, the vertical length H4 from the virtual line VL2 connecting the left and right ends 1Eus, 1Eus at the waist-side end 1Eu of the diaper 1 to the horizontal center 1Euc of the waist-side end 1Eu is preferably smaller than the height H5 of the convex shape at the horizontal center 1Elc of the lower end 1El of the diaper 1 (H4 < H5). Here, the "height of the convex shape" at this time is the height H5 of the convex shape at the lower end 1El in the state where the body circumference part is extended after the suspension test, and is not the height H1 of the convex shape at the lower end 1El when the diaper 1 in the natural state is suspended (FIG. 8). Further, the horizontal center 1Euc of the waist-side end 1Eu of the diaper 1 is set at a position corresponding to the horizontal center of the above virtual line VL2.

[0079] According to the above, in the worn state where the body circumference part of the diaper 1 is extended, the vertical direction (the up and down direction of the diaper 1) difference between the side part and the central part at the waist-side end 1Eu becomes small. Therefore, the diaper 1 can evenly cover the entire body circumference of the wearer. For example, it is possible to suppress the central part in the horizontal direction at the waist-side end of the diaper 1 from sagging and the abdomen of the wearer from being exposed. On the other hand, the central part 1Euc in the horizontal direction at the lower end 1Eu of the diaper 1 forms a convex shape upward, and its height H5 is firmly ensured. Therefore, even after excretion, the absorbent core 11 can adhere closely to the crotch of the wearer, and the discomfort of the wearer due to the sagging of the diaper 1 can be reduced.

[0080] In FIG. 10, the waist-side end 1Eu of the diaper 1 forms a shape curved downward, but the waist-side end 1Eu may be along the horizontal direction (that is, H4 may be zero), or the waist-side end 1Eu may be convexly curved upward.

[0081] Also, in the unfolded and extended state of the diaper 1 (FIG. 5), the length L1 of the stretchable part of the crotch elastic member 40 located on the ventral side of the central position CL of the diaper 1 in the longitudinal direction is preferably longer than the length L2 of the stretchable part of the crotch elastic member 40 located on the dorsal side of the central position CL (L1 > L2).

[0082] The wearer's urethral opening (particularly that of a male) is located closer to the ventral side (front) than directly below the crotch area. Therefore, as described above, it is preferable that the stretchable portion of the crotch elastic members 40 be positioned toward the ventral side in the longitudinal direction of the diaper 1. This allows the crotch elastic members 40 to be more easily positioned in relation to the urethral opening, and the crotch elastic members 40 can directly push the absorbent core 11 up against the urethral opening. This allows the absorbent core 11 to be more easily fitted to the urethral opening, allowing the absorbent core 11 to receive and absorb excrement and further suppress leakage of excrement.

[0083] In addition, when the diaper 1 is in an unfolded and stretched state (FIG. 5), the stretchable portions of the crotch elastic members 40 are preferably arranged across the center position CL of the diaper 1 in the longitudinal direction.

[0084] This allows the crotch elastic members 40 to be positioned at the lower end 1El of the diaper 1 when folded in half during a lifting test. Therefore, even after the absorbent core 11 has absorbed excrement (artificial urine), the crotch elastic members 40 can directly push up the absorbent core 11 at its longitudinal center. Therefore, during a lifting test, the lateral center 1Elc of the lower end 1El of the diaper 1 can be formed into an upwardly convex shape. Furthermore, the longitudinal center CL of the diaper 1 tends to be located directly below the wearer's crotch or slightly toward the wearer's back. The urethral opening of a wearer (especially a male) is located closer to the wearer's ventral area than directly below the crotch. However, when the wearer is standing or lying on his back, excrement from the urethral opening tends to flow toward the wearer's back. Even in this case, the absorbent core 11 is in close contact with the absorbent core 11 at the area directly below the wearer's crotch and its back, allowing the absorbent core 11 to absorb excrement and further prevent leakage of excrement.

[0085] FIG. 11 is an explanatory diagram of a modified diaper 1, showing a schematic plan view of the modified diaper 1 in an unfolded and stretched state. The above is not limiting, and the crotch elastic members 40 do not need to straddle the longitudinal center position CL of the diaper 1, as long as the lateral center portion 1Elc of the lower end 1El of the diaper 1 is convex upward during the lifting test. That is, the crotch elastic members 40 may be positioned closer to the ventral side (see FIG. 11 ) or the dorsal side (not shown) of the longitudinal center position CL of the diaper 1. In this case, the absorbent core 11 at the center position CL is also pushed upward in response to deformation of the absorbent core 11 pushed up by the crotch elastic members 40 located closer to the ventral side or the dorsal side than the center position CL. In this case, the absorbent core 11 at the center position CL is also pushed up. In this case, the lateral center portion 1Elc of the lower end 1El of the diaper 1 can be convex upward during the lifting test.

[0086] The diaper 1 of this embodiment has waist elastic members 24, 25 and a buttocks elastic member 26 as "lateral elastic members" that stretch in the left-right direction. Note that the drawings show only the stretchable portions (portions exhibiting stretchability) of the elastic members (the waist elastic members 24, 25 and the buttocks elastic member 26) of the diaper 1. In this case, when the diaper 1 is in an unfolded and stretched state (FIG. 5), it is preferable that the crotch elastic region ER (the region defined by the crotch elastic member 40) does not overlap with the stretchable portions of the waist elastic members 24, 25 and the buttocks elastic member 26 when viewed in the thickness direction of the diaper 1.

[0087] This prevents the longitudinal stretching force of the crotch elastic members 40 from being inhibited by the lateral stretching force of the waist elastic members 24, 25 and the buttocks elastic members 26. This improves the adhesion of the absorbent core 11 to the crotch region of the wearer before excretion, further reducing leakage of excrement. Furthermore, even after the absorbent core 11 has absorbed excrement (artificial urine), the crotch elastic members 40 can push up the absorbent core 11. This allows the diaper 1 to have a convex shape at the left-right central portion 1Elc of the lower end 1El in a lifting test.

[0088] The diaper 1 of this embodiment includes a plurality of waist elastic members 24, 25 as "continuous elastic members" that are stretchable in the left-right direction and are continuous in a position overlapping the absorbent core 11 in the left-right direction (i.e., continuous from a position corresponding to the left end to a position corresponding to the right end of the absorbent core 11). The continuous elastic members may or may not overlap the absorbent core 11 in the thickness direction.

[0089] In this case, when the diaper 1 is in an unfolded and stretched state, the continuous elastic member closest to the crotch elastic member 40 on the ventral side in the longitudinal direction is the ventral continuous elastic member (here, the lowest ventral waist elastic member 24a), and the continuous elastic member closest to the crotch elastic member 40 on the dorsal side in the longitudinal direction is the dorsal continuous elastic member (here, the lowest dorsal waist elastic member 25a). In this case, it is preferable that the length L3 from the ventral end of the stretchable portion of the crotch elastic member 40 to the ventral continuous elastic member (the lowest ventral waist elastic member 24a) in the longitudinal direction is shorter than the length L4 from the dorsal end of the stretchable portion of the crotch elastic member 40 to the dorsal continuous elastic member (the lowest dorsal waist elastic member 25a) (L3 <L4)。

[0090] As a result, the length (L3) of the region between the waist elastic members 24 and the crotch elastic members 40 is shortened in the longitudinal direction on the ventral side of the diaper 1. In other words, the length (L3) of the region where the elastic members and the absorbent core 11 do not overlap in the thickness direction and the force of the elastic members does not directly act on the absorbent core 11 is shortened. As a result, the absorbent core 11 is more likely to fit closely on the ventral side of the diaper 1 than on the dorsal side. Therefore, the absorbent core 11 is more likely to fit closely to the wearer's urethral opening located on the ventral side, and can receive and absorb excrement, thereby further suppressing leakage of excrement.

[0091] On the other hand, on the back side of the diaper 1, the length (L4) of the region between the waist elastic members 25 and the crotch elastic members 40 is longer in the longitudinal direction. This appropriately reduces the degree of contact of the absorbent core 11 with the wearer's buttocks. This creates a space between the wearer's buttocks and the absorbent core 11, which can accommodate feces or temporarily accommodate large amounts of urine excreted. This prevents excrement from overflowing from the diaper 1.

[0092] In this embodiment, the buttocks elastic members 26 are cut (discontinuous) at positions where they overlap the absorbent core 11 in the thickness direction. However, this is not limiting, and the buttocks elastic members 26 may be continuous from the left end to the right end of the absorbent core 11, in which case the buttocks elastic members 26 also correspond to continuous elastic members.

[0093] In addition, the buttocks elastic members 26 in this embodiment are arranged linearly in the lateral direction. However, this is not limiting, and the diaper 1 may also be provided with elastic members arranged along the lower outer edge of the back outer sheet 22. That is, the elastic members have portions that slope downward from both lateral sides toward the center of the back outer sheet 22 at or below the lower end of the waistband joint 2, and a portion that extends laterally in the lateral direction in the lateral center of the back outer sheet 22. This elastic member also has portions that stretch laterally and corresponds to a lateral elastic member, so it is preferable that it does not overlap with the crotch elastic region ER. Furthermore, if this elastic member is continuous with the absorbent core 11 in the lateral direction at a position that overlaps with it, it corresponds to a continuous elastic member.

[0094] Furthermore, when the crotch elastic members 40 are made up of a plurality of thread-like elastic members (e.g., rubber threads), it is preferable that: When the diaper 1 is in an unfolded and stretched state (FIG. 5), the continuous elastic member closest to the crotch elastic member 40 on the back side in the longitudinal direction is the back-side continuous elastic member (here, the lowest back-side waistline elastic member 25a). The back-side continuous elastic member may or may not overlap the absorbent core 11 in the thickness direction. In this case, it is preferable that the force required to stretch the stretchable portion of the back-side continuous elastic member (the lowest back-side waistline elastic member 25a) to a predetermined length in the left-right direction is smaller than the average force required to stretch each of the crotch elastic members 40 (a plurality of thread-like elastic members) to a predetermined length in the longitudinal direction.

[0095] In the above case, the relatively weak elastic force of the back-side continuous elastic member (back-side waistline elastic member 25a) moderately reduces the degree of contact of the absorbent core 11 with the wearer's buttocks. This creates a space between the wearer's buttocks and the absorbent core 11, which can accommodate feces or temporarily accommodate large amounts of urine excreted. This prevents bodily waste from spilling out of the diaper 1. Meanwhile, the relatively strong elastic force of the crotch elastic members 40 enhances the contact of the absorbent core 11 with the wearer's crotch region, further preventing leakage of bodily waste. Furthermore, even after excretion, the absorbent core 11 can be pushed up against the skin. Therefore, in a lifting test, the central portion 1Elc in the left-right direction of the bottom end 1El of the diaper 1 can be made convex upward.

[0096] The stretching force (the force required to stretch to a predetermined length) of the crotch elastic member 40 and the back continuous elastic member can be measured using a tensile tester (for example, an Instron (Model: 5965) or equivalent). First, the crotch elastic members 40 and the back-side continuous elastic members are cut out from the target diaper 1. The crotch elastic members 40, which are made up of a plurality of thread-like elastic members, are cut out one by one. The cut-out crotch elastic members 40 and back-side continuous elastic members are cut out to the same length to prepare samples. Next, both ends of the sample in the tensile direction are fixed with a pair of chucks of the tensile tester. In the case of the crotch elastic members 40, the tensile direction corresponds to the longitudinal direction of the diaper 1. In the case of the back-side continuous elastic members, the tensile direction corresponds to the left-right direction of the diaper 1. The width of the chucks gripping the sample is kept constant, and the initial distance between the chucks is adjusted so that the sample does not sag or sags slightly. Next, the pair of chucks are moved apart at a constant speed (e.g., 100 mm / min) in the direction of sample extension by a predetermined distance or longer. The measured value (unit: N) when the sample is extended to the predetermined length is taken as the force required to extend the sample to the predetermined length. The average value of each measurement value for the crotch elastic member 40 sample (in this embodiment, five thread-like elastic members) is calculated. The average value is compared with the measurement value for the back-side continuous elastic member, and it is confirmed that the measurement value for the back-side continuous elastic member is smaller.

[0097] In addition, at the center position CL of the diaper 1 in the longitudinal direction, the basis weight (g / m 2 It is preferable that there is no low basis weight region where the basis weight (weight) of the absorbent core 11 is low. The low basis weight region also includes a slit where the basis weight of the absorbent core 11 is zero. In other words, it is preferable that the basis weight of the absorbent core 11 is substantially constant at the central position CL in the longitudinal direction.

[0098] This ensures that the absorbent core 11 can absorb sufficient excrement even when it is a single layer at the longitudinal center position CL. Therefore, leakage of excrement can be suppressed. Furthermore, the low basis weight region can be a folding start point for the absorbent core 11. Therefore, in the diaper 1 of this embodiment, there is no low basis weight region that can be a folding start point at the longitudinal center position CL, thereby reducing the risk of unintended deformation. Therefore, the lateral center portion 1Elc of the bottom end 1El of the diaper 1 in a folded state can more reliably form a convex shape toward the upper side. The absence of a low basis weight region in the absorbent core 11 can be confirmed by a well-known method. For example, a cross section of the absorbent core 11 cut at the center position CL can be observed under magnification using an electron microscope or the like to confirm that the number of fiber cross sections and the number of SAPs are generally constant in the lateral direction.

[0099] 12, 13A, and 13B are explanatory views of the compression section 60. Figures 14A and 14B are schematic cross-sectional views of the absorbent core 11. Note that, for the sake of simplicity, materials such as the backsheet 13 are omitted from Figures 14A and 14B.

[0100] The diaper 1 has a plurality of linear compressed portions 60 formed by compressing the absorbent core 11 in the thickness direction. Specifically, in the "compressed portions" of this embodiment, the absorbent core 11 and the core wrap sheet 18 are compressed in the thickness direction by embossing. The compressed portions 60 are provided over the entire planar area of ​​the absorbent core 11 and the core wrap sheet 18. By compressing, the fiber density of the absorbent core 11 is increased compared to uncompressed portions, and the thickness of the absorbent core 11 is reduced. The compressed portions 60 may be in a compressed state over at least a portion of the thickness of the absorbent core 11. Therefore, the compressed portions are not limited to the above, and may be compressed in the thickness direction from the skin side of the top sheet 12 to the absorbent core 11, or may be compressed from the non-skin side of the absorbent core 11.

[0101] In this embodiment, the compressed portions 60 are formed linearly. The linear compressed portions 60 may be formed, for example, by a collection of multiple dot-like (circular) compressed portions, or may be continuous groove-like compressed portions. Specifically, as shown in FIG. 13A , substantially Z-shaped compressed portions 60A and linear compressed portions 60B are arranged alternately in the longitudinal direction. Multiple rows of the compressed portions 60 are arranged in the left-right direction. The rows of the compressed portions 60 form a zigzag shape that extends longitudinally while meandering in the left-right direction. In rows of compressed portions 60 adjacent to each other in the left-right direction, the positions of the substantially Z-shaped compressed portions 60A are offset in the longitudinal direction. Therefore, the compressed portions 60 are arranged so that they appear as a diagonal grid pattern as a whole. However, the arrangement pattern of the compressed portions 60 is not limited to the pattern shown. Furthermore, dot-like compressed portions or linear compressed portions may be formed discretely.

[0102] When the crotch elastic members 40 are made up of a plurality of thread-like elastic members, it is preferable that compressed portions 60 are disposed between the plurality of crotch elastic members 40 (thread-like elastic members) lined up in the left-right direction, as shown in Fig. 13A. It is sufficient that compressed portions 60 are disposed in at least one of the plurality of regions (four regions between five thread-like elastic members in this embodiment) between the crotch elastic members 40 adjacent in the left-right direction. It is also sufficient that at least some of the linear or dot-like compressed portions 60 are disposed between the crotch elastic members 40 adjacent in the left-right direction.

[0103] FIG. 14A shows a case where no compressed portions 60 are disposed between the crotch elastic members 40 (thread-like elastic members). In this case, the absorbent core 11 between the crotch elastic members 40 is not compressed, and therefore is less rigid and more susceptible to deformation than when compressed. Therefore, after excretion, the absorbent core 11 between the crotch elastic members 40 tends to sag slightly due to the weight of absorbed fluid. In contrast, as shown in FIG. 14B, when compressed portions 60 are disposed between the crotch elastic members 40 (thread-like elastic members), the rigidity of the absorbent core 11 between the crotch elastic members 40 is increased. Therefore, even after excretion, the absorbent core 11 between the crotch elastic members 40 is also easily pushed up in conjunction with the absorbent core 11 being directly pushed up by the crotch elastic members 40. Therefore, the absorbent core 11 can closely contact the crotch region of the wearer, reducing discomfort to the wearer due to poor fit. Furthermore, the gap between the crotch region of the wearer and the absorbent core 11 becomes smaller, which can further prevent leakage of excrement through the gap.

[0104] 13A, the compressed portion 60 preferably has at least some of the oblique compressed portions 61, 62 extending in a direction oblique to the longitudinal direction and the left-right direction in the crotch elastic region ER (the region defined by the crotch elastic member 40). In FIG. 13A, some of the oblique compressed portions 61, 62 located in the crotch elastic region ER are shown in black.

[0105] 13B, the substantially Z-shaped compressed portion 60A has a first inclined portion 61 extending along a first inclined direction (first inclined direction) and a pair of second inclined portions 62 extending from both ends of the first inclined portion 61 to opposite sides in a second inclined direction (second inclined direction) that intersects with the first inclined direction. The multiple linear compressed portions 60B are divided into the first inclined portion 61 extending along the first inclined direction and the second inclined portion 62 extending along the second inclined direction. In other words, the inclined compressed portion has multiple first inclined portions 61 and multiple second inclined portions 62. The crotch elastic region ER has multiple first inclined portions 61 and multiple second inclined portions 62.

[0106] As a result, the inclined compressed portions 61, 62 act as folding start points, facilitating deformation of the absorbent core 11 overlapping the crotch elastic region ER. As a result, in a lifting test, the left-right central portion 1Elc of the lower end 1El of the diaper 1 can be made to have an upwardly convex shape. Furthermore, compared to when the compressed portions 60 are aligned along the longitudinal direction, the longitudinal contraction force of the crotch elastic members 40 is less likely to be hindered, making it easier for the crotch elastic members 40 to push up the absorbent core 11. Furthermore, compared to when the compressed portions 60 are aligned along the left-right direction, the absorbent core 11 overlapping the crotch elastic region ER is less likely to be hindered from deforming into an upwardly convex shape.

[0107] 13A, the first inclined portions 61 are spaced apart in the second inclined direction, and the second inclined portions 62 are spaced apart in the first inclined direction. Therefore, as shown in FIG. 13B, a plurality of substantially diamond-shaped regions r60, each surrounded on all four sides by two first inclined portions 61 and two second inclined portions 62 (compressed portions 60), are formed in the absorbent core 11. In this case, when the diaper 1 is in the unfolded and stretched state, it is preferable that the width W60 in the left-right direction of the region r60 defined by the first inclined portions 61 and the second inclined portions 62 is shorter than the width We of the crotch elastic region ER (W60 <Wer)。

[0108] The horizontal length W60 of the region r60 is the length from the leftmost position to the rightmost position of the inclined compressed portions 61, 62 that surround the region r60. The inclined compressed portions 61, 62 that define the region r60 may be partially separated as in this embodiment, or may be continuous.

[0109] In this way, the approximately diamond-shaped region r60 (one of the diagonal checkered patterns) can be easily accommodated within the portion of the absorbent core 11 overlapping the crotch elastic region ER. Therefore, the obliquely compressed portions 61, 62 that define the region r60 act as folding start points, facilitating deformation of the absorbent core 11 overlapping the crotch elastic region ER. Therefore, in a lifting test, the central portion 1Elc in the left-right direction of the lower end 1El of the diaper 1 can be made to have an upwardly convex shape. Furthermore, while the absorbent core 11 is being folded, the absorbent core 11 in the region r60 can be easily brought into close contact with the wearer's crotch region.

[0110] The diaper 1 of this embodiment also includes an absorbent main body 10 having an absorbent core 11, and an exterior member 20. As shown in Fig. 2, the exterior member 20 preferably includes a pair of waist-surrounding sections 20A, 20C and a crotch section 20B connecting the pair of waist-surrounding sections 20A, 20C. The pair of waist-surrounding sections 20A, 20C of the exterior member 20 are sections that cover the waist of the wearer. In the case of a pants-type diaper like the diaper 1 of this embodiment, the sections of the exterior member 20 that overlap with the waist-surrounding joint section 2 in the longitudinal direction are referred to as the waist-surrounding sections 20A, 20C.

[0111] In the above case, the outer member 20 is continuous from the waistline portion 20A on the ventral side through the crotch portion 20B to the waistline portion 20C on the dorsal side. Therefore, in the crotch portion 1B of the diaper 1, the non-skin side of the absorbent main body 10 is not exposed and is covered by the outer member 20. As a result, the absorbent core 11 (absorbent main body 10), which has gained weight after excretion, is pulled up by the crotch portion 20B of the outer member 20 that is continuous with the waistline portions 20A, 20C. This reduces discomfort to the wearer caused by the absorbent core 11 sagging. The pair of waistline portions 20A, 20C and the crotch portion 20B may be a single continuous sheet member or separate sheet members joined together.

[0112] ===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 it goes without saying that the present invention includes equivalents thereof. [Explanation of symbols]

[0113] 1. Pants-type disposable diapers (absorbent articles), 2 waist joint, 10. Absorbent body; 11 absorbent core, 12 top sheet, 13 back seat, 15 middle seat, 16 side sheet, 17 elastic member cover sheet, 20 exterior components, 21 ventral outer sheet, 22 dorsal outer sheet, 23 inner layer sheet, 24 (ventral side) waist elastic member (transverse elastic member, continuous elastic member), 25 (back side) waist elastic member (transverse elastic member, continuous elastic member), 26 buttock elastic member (transverse elastic member), 31 cover sheet, 32 cover sheet, 40 crotch elastic member, 50 Test stand, 51 Clip, 52 cylindrical jig, 53 tape, 60 compression section, 61 First inclined section (inclined compression section), 62 Second inclined section (inclined compression section),

Claims

1. 1. An absorbent article having an absorbent core, In the deployed and extended state, having a longitudinal direction, a left-right direction, and a thickness direction which intersect with one another, The garment has a crotch elastic member that stretches in the longitudinal direction, At least a part of the crotch elastic member is provided in the left-right central portion of the crotch portion, which is a central region when the absorbent article is divided into three equal parts in the longitudinal direction, At a central position of the absorbent article in the longitudinal direction, the absorbent core is a single layer, An absorbent article characterized in that when a liquid is dripped onto the absorbent article at the center position in the left-right direction at the folded position in the longitudinal direction, and then a lifting test is conducted in which the waist side end of the absorbent article, which is folded in half in the longitudinal direction, and both ends in the left-right direction are grasped and lifted, the center position in the left-right direction of the lower end of the absorbent article forms a convex shape facing upward.

2. The absorbent article according to claim 1, An absorbent article characterized in that, in an unfolded and stretched state, the length of the stretchable portion of the crotch elastic member located on the ventral side of the center position of the absorbent article in the longitudinal direction is longer than the length of the stretchable portion of the crotch elastic member located on the dorsal side of the center position.

3. The absorbent article according to claim 1 or 2, An absorbent article, characterized in that, in a deployed and stretched state, the stretchable portions of the crotch elastic members are arranged across a central position of the absorbent article in the longitudinal direction.

4. The absorbent article according to claim 1 or 2, a lateral elastic member that stretches in the left-right direction; In the deployed and extended state, When the area defined by the crotch elastic member is defined as the crotch elastic area, An absorbent article characterized in that, when the absorbent article is viewed in the thickness direction, the crotch elastic region does not overlap with the stretchable portion of the lateral elastic member.

5. The absorbent article according to claim 1 or 2, The absorbent core has a plurality of continuous elastic members that are stretchable in the left-right direction and are continuous at positions that overlap the absorbent core in the left-right direction. In the deployed and extended state, The continuous elastic member closest to the crotch elastic member on the abdominal side in the longitudinal direction is defined as an abdominal side continuous elastic member, When the continuous elastic member closest to the crotch elastic member on the back side in the longitudinal direction is the back side continuous elastic member, An absorbent article characterized in that, in the longitudinal direction, the length from the ventral end of the stretchable portion of the crotch elastic member to the ventral continuous elastic member is shorter than the length from the dorsal end of the stretchable portion of the crotch elastic member to the dorsal continuous elastic member.

6. The absorbent article according to claim 1 or 2, The absorbent core has a continuous elastic member that is stretchable in the left-right direction and is continuous with the absorbent core at a position overlapping the left-right direction, The crotch elastic members are a plurality of thread-like elastic members, In the unfolded and stretched state, when the continuous elastic member closest to the crotch elastic member on the back side in the longitudinal direction is the back side continuous elastic member, an absorbent article characterized in that the force required to stretch the stretchable portion of the back-side continuous elastic member to a predetermined length in the left-right direction is smaller than the average value of the forces required to stretch each of the plurality of thread-like elastic members to the predetermined length in the longitudinal direction.

7. The absorbent article according to claim 1 or 2, An absorbent article characterized in that there is no low basis weight region in the central position of the absorbent article in the longitudinal direction, where the basis weight of the absorbent core is lower than that of the surrounding area.

8. The absorbent article according to claim 1 or 2, a compression section that compresses the absorbent core in the thickness direction, The crotch elastic members are a plurality of thread-like elastic members, An absorbent article, characterized in that the compressed portion is disposed between the plurality of thread-like elastic members aligned in the left-right direction.

9. The absorbent article according to claim 1 or 2, a compression section that compresses the absorbent core in the thickness direction, In the deployed and extended state, When the area partitioned by the crotch elastic member is defined as the crotch elastic area, the compression portion has at least a portion of an inclined compression portion in the crotch elastic area that is inclined with respect to the longitudinal direction and the left-right direction.

10. The absorbent article according to claim 9, The inclined compression section has a plurality of first inclined sections along a first inclined direction and a plurality of second inclined sections along a second inclined direction intersecting the first inclined direction, the plurality of first inclined portions are arranged at intervals in the second inclined direction, The second inclined portions are arranged at intervals in the first inclined direction, An absorbent article characterized in that, in an unfolded and stretched state, the left-right length of the area partitioned by the plurality of first inclined portions and the plurality of second inclined portions is shorter than the left-right length of the crotch elastic region.

11. The absorbent article according to claim 1 or 2, When a pre-absorption lifting test is conducted in which the absorbent article, which is in a dry state and folded in half in the longitudinal direction, is lifted by grasping the end portion on the waist side and both ends in the left-right direction, the central portion in the left-right direction of the lower end of the absorbent article forms a convex shape facing upward, An absorbent article, wherein the height of the convex shape in the lifting test is greater than the height of the convex shape in the pre-absorption lifting test.

12. The absorbent article according to claim 1 or 2, a pants-type absorbent article including waist elastic members that stretch in the left-right direction, When the lifting test was carried out, The waist side end of the absorbent article has a concave shape that is curved downward, An absorbent article characterized in that the height of the convex shape is smaller than the vertical length from an imaginary line connecting the left and right ends of the waist side end of the absorbent article to the center of the left and right directions of the waist side end.

13. The absorbent article according to claim 1 or 2, a pants-type absorbent article including waist elastic members that stretch in the left-right direction, After the lifting test, the gripping position of the waist side end of the absorbent article is widened to a length that is 80% of the length when the waist side end of the absorbent article is most stretched in the left-right direction. An absorbent article characterized in that the vertical length from an imaginary line connecting the left and right ends of the waist side end of the absorbent article to the left-right center of the waist side end is smaller than the height of the convex shape.

14. The absorbent article according to claim 1 or 2, The absorbent body includes the absorbent core and an exterior member, The absorbent article is characterized in that the exterior member has a pair of waistband portions and a crotch portion connecting the pair of waistband portions.

Images