Absorbent panty-type items

Abstract

When wearing absorbent items, the absorbent items are made easier to bring into contact with the excretory opening, while improving the durability and absorbency of the central part of the absorbent core in the left-right direction. [Solution] A pair of pants-type absorbent articles comprising a pair of waist sections, a crotch section, and an absorbent core, wherein in the unfolded and stretched state, the crotch section is provided on the non-skin side of the absorbent core and has a crotch elastic member along the longitudinal direction, at least a part of the crotch elastic member is provided in the central part in the left-right direction, the crotch section is provided with a crotch elastic region partitioned by the crotch elastic member, the longitudinal center of the crotch elastic region is provided on the abdominal side of the longitudinal center of the pants-type absorbent article, the absorbent core has a superabsorbent polymer and is continuous along the longitudinal direction and has a pair of low-basis-weight sections with a lower basis weight than the surrounding area, provided in the central part of the absorbent core divided into three equal parts in the longitudinal direction, and the average basis weight of the absorbent core in the part overlapping with the crotch elastic region when viewed in the thickness direction is equal to or greater than the average basis weight of the absorbent core in the crotch section.

Description

Technical Field

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

Background Art

[0002] The disposable diaper disclosed in Patent Document 1 includes an absorbent body having a central opening at the center in the width direction and side slits on both sides of the central opening, and a central elastic member along the length direction provided so as to overlap the central opening of the absorbent body. Thereby, during wearing, the central portion in the width direction constitutes a central bent portion that bends in a convex shape toward the excretory opening to be in contact with the wearer's skin, and the side slits constitute side bent portions, so as to improve the wearing comfort for the wearer and prevent leakage of excreta.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Although the disposable diaper disclosed in Patent Document 1 has portions of the absorbent body with small thickness such as the central opening and side slits to facilitate bending of the absorbent body, when the thin portion of the absorbent body is a portion with low basis weight of the absorbent body like a slit, the absorbent body is prone to collapse during wearing, which reduces durability and may impair the wearing comfort. In addition, during wearing, the portion of the deformed absorbent body that comes into contact with the excretory opening is a portion where the thickness of the absorbent body is small and the basis weight of the absorbent body is low, so the absorbability of excreta is reduced, and there is a risk that excreta cannot be properly absorbed.

[0005] The present invention has been made in view of the above-mentioned problems, and its objective is to provide an absorbent article that makes it easier to bring the absorbent article into contact with the excretory opening of excrement when wearing the absorbent article, while improving the durability and absorbency of the central part in the left-right direction of the absorbent core. [Means for solving the problem]

[0006] The main invention for achieving the above objective is a pair of pants-type absorbent articles having an absorbent core, comprising a pair of waist sections joined at joints on both sides, and a crotch section below the joints, wherein in the unfolded and stretched state, the article has longitudinal, left-right, and thickness directions that intersect with each other, the crotch section is provided on the non-skin side of the absorbent core and has one or more crotch elastic members provided at least along the longitudinal direction, at least a portion of the crotch elastic member is provided in the central part in the left-right direction, and the crotch section has the crotch An elastic crotch region is provided, partitioned by a lower elastic member, the longitudinal center of the elastic crotch region is located ventrally to the longitudinal center of the pants-type absorbent article, the absorbent core has a superabsorbent polymer and is continuous along the longitudinal direction, and is provided in the central part of the three equal parts obtained by dividing the absorbent core in the longitudinal direction, with a lower basis weight than the surrounding area, and the average basis weight of the absorbent core in the part that overlaps with the elastic crotch region when viewed in the thickness direction is equal to or greater than the average basis weight of the absorbent core in the crotch area. This is a pant-type absorbent article characterized by the following features. Other features of the present invention will be made clearer by description in 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 makes it easier to bring the absorbent article into contact with the excretory opening of the excrement when wearing the absorbent article, while improving the durability and absorbency of the central part in the left-right direction of the absorbent core. [Brief explanation of the drawing]

[0008] [Figure 1] This is a schematic front view of a disposable pull-up diaper 1. [Figure 2] This is a schematic plan view of diaper 1 in its unfolded and extended state, as seen from the skin side. [Figure 3] Figure 2 is a schematic cross-sectional view at position CC. [Figure 4] Figure 2 is a schematic cross-sectional view taken along the arrow at the CL position. [Figure 5] This diagram illustrates the absorbent core 11 and the crotch elastic region ER. [Figure 6] This is a diagram illustrating the absorbent core 11. [Figure 7] This is a schematic cross-sectional view of the absorbent core 11 in its extended state when the crotch elastic member 40 is not present. [Figure 8] This is a schematic cross-sectional view of the absorbent core 11 in the worn state when the crotch elastic member 40 is not present. [Figure 9] This diagram illustrates another form of the crotch elastic region (ER). [Figure 10] This diagram illustrates the deformation of the absorbent core 11 of diaper 1 when worn. [Figure 11] This diagram illustrates the absorbent core 11 in the crotch area 1B. [Figure 12] This is a diagram illustrating an absorbent core 11 having a compression section 80. [Figure 13] This is a modified example of the absorbent body 10. [Figure 14] This is a schematic plan view of diaper 100 in its unfolded and extended state, as seen from the skin side. [Modes for carrying out the invention]

[0009] The following matters become clear from this specification and the accompanying drawings: (Aspect 1) A pair of pants-type absorbent articles having an absorbent core, comprising a pair of waist sections joined at both sides by a joint, and a crotch section below the joint, wherein in the unfolded and stretched state, the pants have longitudinal, left-right, and thickness directions that intersect with each other, the crotch section is provided on the non-skin side of the absorbent core and has one or more crotch elastic members provided at least along the longitudinal direction, at least a portion of the crotch elastic members is provided in the central part in the left-right direction, and the crotch section has a crotch elastic region defined by the crotch elastic members. The pants-type absorbent article is characterized in that a crotch elastic region is provided, the center of the longitudinal direction of the crotch elastic region is located ventrally from the center of the longitudinal direction of the pants-type absorbent article, the absorbent core has a highly absorbent polymer and is continuous along the longitudinal direction, and is provided in the central part of the three equal parts of the longitudinal direction of the absorbent core, having a lower basis weight than the surrounding area, and the average basis weight of the absorbent core in the part that overlaps with the crotch elastic region when viewed in the thickness direction is equal to or greater than the average basis weight of the absorbent core in the crotch area.

[0010] According to the pant-type absorbent article of Embodiment 1, the longitudinal center of the crotch elastic region is located ventrally from the longitudinal center of the pant-type absorbent article, and it has a pair of low basis weight sections along the longitudinal direction, and the absorbent core has an absorbent core in which the average basis weight of the absorbent core in the part that overlaps with the crotch elastic region when viewed in the thickness direction is greater than or equal to the average basis weight of the absorbent core in the crotch area. This makes it easier to deform the central part of the absorbent core in the left-right direction toward the skin side, and the part between the central part in the left-right direction and the side edges toward the non-skin side, thereby making it easier to bring it into contact with the excretion opening for excretion such as urine, and thus improving the durability and absorbency of the central part of the absorbent core in the left-right direction.

[0011] (Aspect 2) In the unfolded and extended state, the absorbent core has a wide portion that is the longest in the left-right direction and a narrow portion that is shorter in the left-right direction than the wide portion, and in the longitudinal direction, there is a portion in which the crotch elastic region, the low basis weight portion and the narrow portion overlap. This is the characteristics of the pants-type absorbent article according to embodiment 1.

[0012] According to the pants-type absorbent article of Aspect 2, the central portion in the left-right direction of the absorbent core can be easily deformed toward the skin side, and the portion between the central portion in the left-right direction and the side end portions can be easily deformed toward the non-skin side, whereby it is possible to improve the absorbency of the absorbent core while reducing discomfort during wearing.

[0013] (Aspect 3) The pants-type absorbent article according to Aspect 1 or 2 is characterized in that, in the deployed and stretched state, when viewed in the thickness direction, the crotch elastic member does not have a portion that does not overlap the absorbent core, and the crotch elastic region is provided only in the central portion of three equally divided portions of the absorbent core in the left-right direction.

[0014] According to the pants-type absorbent article of Aspect 3, the central portion in the left-right direction of the absorbent core can be easily deformed toward the skin side, and the portion between the central portion in the left-right direction and the side end portions can be easily deformed toward the non-skin side, whereby it is possible to improve the absorbency of the absorbent core while reducing discomfort during wearing.

[0015] (Aspect 4) The pants-type absorbent article according to any one of Aspects 1 to 3 is characterized in that, in the deployed and stretched state, the low basis weight portion is not provided in the back-side portion of three equally divided portions of the absorbent core in the longitudinal direction.

[0016] According to the pants-type absorbent article of Aspect 4, in the crotch portion in the worn state, the central portion in the left-right direction of the absorbent core can be easily deformed toward the skin side and the portion between the central portion in the left-right direction and the side end portions can be easily deformed toward the non-skin side, while on the back side of the crotch portion, deformation of the absorbent core similar to that in the crotch portion can be easily suppressed, making it easy to follow the roundness of the wearer's buttocks.

[0017] (Aspect 5) The absorbent core has a plurality of compressed portions compressed in the thickness direction, and the pair of low-basis-weight portions have one low-basis-weight portion provided on one side in the left-right direction and the other low-basis-weight portion provided on the other side in the left-right direction, and in the unfolded and extended state, when viewed in the thickness direction, the one low-basis-weight portion has a portion that overlaps with the compressed portion, and the other low-basis-weight portion has a portion that overlaps with the compressed portion, characterized in that the pants-type absorbent article is any of embodiments 1 to 4.

[0018] According to the pant-type absorbent article of Embodiment 5, the rigidity of the low-basis-weight portion can be improved by the low-basis-weight portion that overlaps with the compressed portion when viewed in the thickness direction. This makes it easier to deform the absorbent core while reducing the risk of the absorbent core losing its shape, thereby improving the durability of the absorbent core.

[0019] (Aspect 6) The absorbent core has a compressed portion that is compressed in the thickness direction, and in the unfolded and stretched state, it has a portion where the crotch elastic region and the compressed portion overlap when viewed in the thickness direction, making it a pant-type absorbent article according to any of embodiments 1 to 5.

[0020] According to the pant-type absorbent article of embodiment 6, the rigidity of the crotch elastic region can be improved by the crotch elastic region that overlaps with the compressed portion when viewed in the thickness direction. Therefore, when worn, the contraction of the crotch elastic member makes it easier to bring the absorbent core closer to the excretory opening, while reducing the risk of the absorbent core losing its shape and improving the durability of the absorbent core.

[0021] (Aspect 7) The pants-type absorbent article according to any of embodiments 1 to 6 is characterized in that, in the unfolded and extended state, the crotch elastic region is provided up to the dorsal portion of the three equal parts obtained by dividing the absorbent core in the longitudinal direction.

[0022] According to the absorbent pant-type article of Embodiment 7, by making it easier to make the absorbent pant-type article fit snugly from the crotch area to the back, for wearers who are able to move around such as walking, the absorbent pant-type article can be made to fit snugly from the crotch area to the back while being worn, and the presence of the absorbent pant-type article can be made less visible from the outside.

[0023] (Pattern 8) In the unfolded and extended state, the crotch elastic region is not provided in the dorsal portion of the three equal parts obtained by dividing the absorbent core in the longitudinal direction. This is a pant-type absorbent article according to any of embodiments 1 to 6.

[0024] According to the absorbent pant-type article of embodiment 8, by making it difficult for the portion of the absorbent pant-type article from the crotch area to the back to adhere closely to the wearer's body, when the wearer is lying down, such as being bedridden, it becomes easier to create a space between the wearer's body and the absorbent pant-type article from the crotch area to the back, making it easier to absorb excrement over a wider area.

[0025] (Aspect 9) In the unfolded and extended state, the pant-type absorbent article according to any of embodiments 1 to 8 is characterized in that, when viewed in the thickness direction, the area overlapping with the absorbent core is colored in the left-right direction, and the area between the pair of low-basis-weight portions in the left-right direction is white.

[0026] According to the pant-type absorbent article of embodiment 9, the colored side edges of the absorbent core make it easier for the wearer to recognize that the absorbent core is provided not only between the white low-basis-weight sections, but also in the parts outside the low-basis-weight sections in the left-right direction that are deformed toward the skin, and that these parts are capable of absorbing excrement.

[0027] (Aspect 10) In the unfolded and extended state, the ventral end of the crotch elastic member located on the ventral side is located further ventral than the ventral end of the low-basis-weight portion located on the ventral side, as is the case with any of embodiments 1 to 9 of the pant-type absorbent article.

[0028] According to the pant-type absorbent article of embodiment 10, the contractile force of the crotch elastic member provided on the ventral side of the low-basis-weight portion makes it easier to deform the absorbent core to conform to the wearer's body at the deformation starting point at the ventral end of the low-basis-weight portion, thus making it easier to fit to the wearer's skin.

[0029] (Aspect 11) In the unfolded and extended state, the crotch elastic region is provided between the pair of low-basis-weight portions in the left-right direction, characterized in any of embodiments 1 to 10 of the pant-type absorbent article.

[0030] According to the pant-type absorbent article of embodiment 11, the central part and side ends of the absorbent core in the left-right direction are easily deformed toward the skin side, and the area between the central part and side ends in the left-right direction toward the non-skin side, making it easier to bring the absorbent article into contact with the excretory opening for urine and other excrement.

[0031] (Aspect 12) The pair of low-basis-weight portions comprises a one-side low-basis-weight portion provided on one side in the left-right direction and a other-side low-basis-weight portion provided on the other side in the left-right direction, and in the unfolded and extended state, at the center of the longitudinal direction of the pants-type absorbent article, the length from one side edge in the left-right direction of the crotch elastic region to the inner edge in the left-right direction of the one-side low-basis-weight portion is longer than the length from one side edge in the left-right direction of the absorbent core to the outer edge in the left-right direction of the one-side low-basis-weight portion. This is the pants-type absorbent article of embodiment 11.

[0032] According to the absorbent pant-type article of embodiment 12, when the absorbent pant-type article is worn, the length from one side edge of the absorbent core in the left-right direction to the left-right outer edge of the low-basis-weight portion on one side is longer than the length from one side edge of the elastic crotch area in the left-right direction to the left-right inner edge of the low-basis-weight portion on one side in the left-right direction. This makes it easier to absorb excrement in the central part of the longitudinal direction, even at the side edges of the absorbent core, and makes it easier to suppress lateral leakage of excrement from the absorbent pant-type article.

[0033] (Aspect 13) The pair of low-basis-weight portions each have a curved portion that protrudes outward in the left-right direction, the apex of the curved portion is located at the outermost part of the low-basis-weight portion in the left-right direction, and in the unfolded and extended state, at the position of the apex of the curved portion in the longitudinal direction, the length from one side edge of the crotch elastic region in the left-right direction to the inner edge of the one low-basis-weight portion in the left-right direction is longer than the length from one side edge of the absorbent core in the left-right direction to the outer edge of the one low-basis-weight portion in the left-right direction. This is a pant-type absorbent article of embodiment 12.

[0034] According to the pant-type absorbent article of embodiment 13, even when the low-basis-weight portion has a curved portion, when the pant-type absorbent article is worn, the length from one side edge of the absorbent core in the left-right direction to the left-right outer edge of the low-basis-weight portion on one side is longer than the length from one side edge of the crotch elastic region in the left-right direction to the left-right inner edge of the low-basis-weight portion on one side in the left-right direction. This makes it easier to absorb excrement in the central part of the longitudinal direction, even at the side edges of the absorbent core, and makes it easier to suppress lateral leakage of excrement from the pant-type absorbent article.

[0035] (Aspect 14) In the unfolded and extended state, the pair of low-basis-weight portions each have a straight portion along the longitudinal direction and an inclined portion that slopes from the ventral side to the dorsal side in the longitudinal direction and from the inner side to the outer side in the left-right direction, wherein the inclined portion is provided on the dorsal side of the straight portion, and the straight portion and the inclined portion are continuous, making this a pant-type absorbent article of any of embodiments 1 to 13.

[0036] According to the pant-type absorbent article of embodiment 14, when worn, it is possible to easily absorb excrement from the back of the crotch area, while the absorbent core can be easily deformed to conform to the shape of the wearer's buttocks.

[0037] (Aspect 15) In the unfolded and extended state, both ends of the absorbent core each have a core inclined portion that slopes from the ventral side to the dorsal side in the longitudinal direction and from the inside to the outside in the left-right direction, and on one side in the left-right direction, the inclined portion is provided at a position that overlaps with the core inclined portion in the longitudinal direction, and on the other side in the left-right direction, the inclined portion is provided at a position that overlaps with the core inclined portion in the longitudinal direction, characterized in that the pants-type absorbent article of embodiment 14.

[0038] According to the pant-type absorbent article of embodiment 15, when worn, it is possible to easily absorb excrement from the crotch area to the back, while the absorbent core can be easily deformed to conform to the shape of the wearer's buttocks.

[0039] (Aspect 16) An absorbent pant-type absorbent article according to any of embodiments 1 to 15, characterized in that it has an absorbent body equipped with the absorbent core, the absorbent body has a pair of leak-proof wall portions that can stand upright on the skin side at the left-right side, and a pair of side elastic members that are expandable and contractible along the longitudinal direction and are provided on both the left-right outer sides of the crotch elastic member, and at least a portion of the side elastic member is provided between the position of the starting point for the upright position of the leak-proof wall portion in the left-right direction and the side end of the absorbent core at the center of the longitudinal direction of the pant-type absorbent article on one side in the left-right direction.

[0040] According to the pant-type absorbent article of embodiment 16, the leakage-proof wall portion is more likely to stand up due to the contraction of the side elastic member, making it easier to suppress leakage of excrement.

[0041] (Aspect 17) The pants-type absorbent article according to any of embodiments 1 to 16 is characterized by having a pair of side elastic members that are stretchable along the longitudinal direction and are provided on both the left and right outer sides of the crotch elastic member, and the back end of the side elastic member is provided further back than the back end of the low basis weight portion.

[0042] According to the pant-type absorbent article of embodiment 17, the low basis weight portion facilitates deformation of the absorbent core, and the dorsal end of the side elastic member is positioned dorsally further back than the dorsal end of the low basis weight portion. This makes it easier for the absorbent core and the pant-type absorbent article to come into contact with the wearer's crotch and skin due to the contraction of the crotch elastic member and the side elastic member, compared to when the dorsal end of the side elastic member is positioned ventrally further back than the dorsal end of the low basis weight portion.

[0043] (Aspect 18) A pair of side elastic members, which are stretchable along the longitudinal direction and provided on both the left and right outer sides of the crotch elastic member, is a pant-type absorbent article according to any of embodiments 1 to 17, wherein the absorbent core has a wide portion that is the longest in the left and right direction and a narrow portion that is shorter in the left and right direction than the wide portion, and in the longitudinal direction, in the region of the narrow portion that overlaps with the shortest portion in the left and right direction, the side elastic members do not overlap with the absorbent core when viewed in the thickness direction.

[0044] According to the pant-type absorbent article of embodiment 18, when viewed in the thickness direction, the side elastic member does not overlap with the absorbent core in the region where the length of the absorbent core in the left-right direction is shortest. As a result, the contraction of the crotch elastic member and the side elastic member makes it easier for the absorbent core and the pant-type absorbent article at the position overlapping with the narrowest part in the longitudinal direction to come into contact with the wearer's skin.

[0045] ===Implementation Method=== Hereinafter, an example of an absorbent pant-type article according to the embodiment of the present invention will be described using an adult disposable pant-type diaper (hereinafter also referred to as "diaper 1"). However, the absorbent pant-type 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.

[0046] ===First Embodiment=== <<Basic composition of a pull-up type disposable diaper 1>> Figure 1 is a schematic front view of a pull-up type disposable diaper 1. Figure 2 is a schematic top view of the diaper 1 in its unfolded and extended state, as seen from the skin side. Figure 3 is a schematic cross-sectional view at position CC in Figure 2. Figure 4 is a schematic cross-sectional view at position CL in Figure 2.

[0047] In diaper 1, the "unfolded state" refers to the state in which the waist joint (joint) 2, described later, is undone, the folds of diaper 1 are opened in the longitudinal direction, and the diaper is unfolded flat. The "stretched state" of diaper 1 refers to the state in which the entire diaper 1 is stretched without wrinkles by stretching each of the elastic members of diaper 1 (for example, the waist elastic members 24 and 25 and the leak-proof wall elastic member 51 described later). Specifically, it refers to the state in which the dimensions of each material constituting diaper 1 (for example, the top sheet 12 and inner layer sheet 23 described later) are stretched to match or close to the dimensions of the individual member.

[0048] Diaper 1, in the pant-type state shown in Figure 1 (pant-type state), has intersecting vertical, horizontal, and front-to-back directions, and has a waist opening BH and a pair of leg openings LH. In the unfolded state shown in Figure 2, it has intersecting longitudinal, horizontal, and thickness directions. The longitudinal direction is along the vertical direction in the pant-type state. The thickness direction is the direction in which the components constituting diaper 1 are stacked (see Figures 3 and 4). In the vertical direction, the waist opening BH side is considered the upper side, and the crotch side is considered the lower side. In the front-to-back direction, the side facing the wearer's abdomen is considered the front side, and the side facing the wearer's back is considered the back side. In the thickness direction, the side that comes into contact with the wearer's body (skin) is considered the skin side, and the opposite side is considered the non-skin side. In Figure 2, etc., the center (center position) C-C indicates the center in the horizontal direction, and the center CL indicates the center in the longitudinal direction.

[0049] Furthermore, as shown in Figure 3, the diaper 1 has an absorbent body 10 and an outer covering member 20 positioned on the non-skin side of the absorbent body 10. The absorbent body 10 and the outer covering member 20 are joined (fixed) together in an adhesive area to which an adhesive such as a hot melt adhesive is applied. Cover sheets 31 and 32 may be provided to cover both ends of the absorbent body 10 in the longitudinal direction from the skin side. This prevents the edges of the absorbent body 10 from digging into the wearer and prevents the absorbent body 10 from opening.

[0050] Diaper 1 has a pair of waist sections 1A and 1C joined at waist joints 2 (joints) on both sides, and a crotch section 1B below the waist joints 2. By folding the unfolded diaper 1 in half at the longitudinal center position CL and joining the left and right sides of the ventral waist section 1A and the dorsal waist section 1C, it becomes the pant-type diaper 1 shown in Figure 1. Examples of joining methods for the waist joints 2 include welding and joining with adhesive.

[0051] As shown in Figure 4, the absorbent body 10 comprises an absorbent core 11 that absorbs excretory fluid, a liquid-permeable top sheet 12 (e.g., nonwoven fabric) positioned on the skin side in the thickness direction relative to the absorbent core 11, a liquid-impermeable back sheet 13 (e.g., a resin film such as polyethylene or polypropylene) positioned on the non-skin side in the thickness direction relative to 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 crotch elastic member 40 (details to be described later), which expands and contracts in the longitudinal direction, from the non-skin side.

[0052] The absorbent core 11 absorbs and retains excretory fluids such as urine. The surface of the absorbent core 11 may be covered with a liquid-permeable core wrap sheet 18 (for example, tissue paper). Examples of the absorbent core 11 include liquid-absorbing fibers such as pulp containing a superabsorbent polymer (SAP) that have been molded into a predetermined shape, but it is not limited to this. At least the absorbent core 11 has a superabsorbent polymer (SAP), and it may be configured without an absorbent material such as liquid-absorbing fibers. As shown in Figure 5, the absorbent core 11 of this embodiment has a wide section 11h which is the widest in the left-right direction and a narrow section 11n which is shorter in the left-right direction than the wide section 11h, and the narrow section 11n is located in the center of the longitudinal direction of the absorbent core 11, so that the center of the longitudinal direction is constricted inward in the left-right direction. In addition, the absorbent core 11 has portions at both the ventral and dorsal ends that are shorter in length in the lateral direction than the wide portion 11h. The portion that is shorter in length in the lateral direction than the wide portion 11h and includes the center CL in the longitudinal direction of the diaper 1 is defined as the narrow portion 11n. The planar shape of the absorbent core 11 is not particularly limited. Furthermore, the absorbent core 11 has a low basis weight portion 11s that is lower in basis weight than the surrounding area. The low basis weight portion 11s will be described later.

[0053] A pair of leak-proof walls 50 are provided on both sides of the absorbent body 10 in the left-right direction, extending along the longitudinal direction. As shown in Figure 4, portions of the side sheet 16 extending from both sides of the non-skin side of the back sheet 13 are folded at multiple points and provided on both sides of the skin side of the top sheet 12 in the left-right direction, forming the leak-proof walls 50. The leak-proof walls 50 (back sheet 13) are fixed to the top sheet 12 by fixing parts 50a and 50b. The inner ends of the fixing parts 50b in the left-right direction become the starting point e50 of the upright position of the leak-proof walls 50. A leak-proof elastic member 51 (for example, a filamentous elastic member) is attached to the leak-proof walls 50 in an extended state along the longitudinal direction. Due to the elasticity of the leak-proof elastic member 51, the leak-proof walls 50 can stand up on the wearer's skin side and block excrement. Furthermore, at both ends of the absorbent body 10, leg-circumference elastic members 52 that expand and contract along the longitudinal direction are provided on the left and right sides of the leak-proof wall portion 50. When the diaper 1 is viewed in the thickness direction in its unfolded and extended state, the leg-circumference elastic members 52 are elastic members that have a portion that overlaps with the absorbent core 11 and a portion that does not overlap with the absorbent core 11. Due to the elasticity of the leg-circumference elastic members 52, the diaper 1 can fit around the wearer's legs. The leak-proof wall portions 50, 50 and the leg-circumference elastic members 52 are not necessarily required.

[0054] The exterior member 20 is a sheet member having a shape in which the central part in the longitudinal direction is constricted inward in the left-right direction. As shown in Figure 3, the exterior member 20 has a ventral outer layer sheet 21, a dorsal outer layer sheet 22, an inner layer sheet 23, torso elastic members 24, 25, and buttock elastic member 26.

[0055] The ventral outer layer sheet 21, the dorsal outer layer sheet 22, and the inner layer sheet 23 can be exemplified by flexible sheet materials such as nonwoven fabric. The inner layer sheet 23 forms the outer shape of the outer layer member 20 and is a continuous sheet material from the ventral waist portion 1A through the crotch area 1B to the dorsal waist portion 1C. The ventral outer layer sheet 21 is located on the non-skin side of the inner layer sheet 23 and is positioned in part of the ventral waist portion 1A. The ventral outer layer sheet 21 overlaps with the waist joint 2 in the longitudinal direction, and its length in the longitudinal direction is the same as that of the waist joint 2. The dorsal outer layer sheet 22 is located on the non-skin side of the inner layer sheet 23 and is positioned in part of the dorsal waist portion 1C and the crotch area 1B. The dorsal outer layer sheet 22 overlaps with the waist joint 2 in the longitudinal direction and extends below the crotch from the waist joint 2. In the unfolded state of diaper 1, the ventral outer layer sheet 21 and the dorsal outer layer sheet 22 are separated in the longitudinal direction, and the inner layer sheet 23 is exposed to the outside as the non-skin side of diaper 1.

[0056] The ventral torso elastic member 24, the dorsal torso elastic member 25, and the buttock elastic member 26 are elastic members that stretch in the left-right direction, and thread-like elastic members can be exemplified. As shown in Figure 2, the torso elastic members 24 and 25 overlap with the torso joint 2 in the longitudinal direction. The buttock elastic member 26 is located below the crotch in the longitudinal direction (below in the vertical direction) than the torso joint 2. The number of buttock elastic members 26 is not particularly limited.

[0057] Furthermore, the waist elastic members 24, 25 and the buttock elastic member 26 are arranged side by side in the vertical direction in a pant-like state between the inner layer sheet 23 and the ventral outer layer sheet 21 or the dorsal outer layer sheet 22, and are fixed in an extended state along the left-right direction. As a result, the outer member 20 fits the wearer's waist and buttocks. Note that the waist elastic members 24, 25 and the buttock elastic member 26 each only need to have a portion that expands and contracts along the left-right direction, and the waist elastic members 24, 25 and the buttock elastic member 26 may also have a curved portion in addition to the portion that expands and contracts along the left-right direction.

[0058] The basic configuration of diaper 1 has been described above, but the configuration of diaper 1 described above is just one example and is not limited thereto. For example, a liquid-permeable intermediate sheet (e.g., nonwoven fabric) may be placed between the top sheet 12 and the absorbent core 11. Also, the outer covering member 20 of this embodiment is composed of a single member that is continuous in the longitudinal direction from the ventral side to the dorsal side, but is not limited thereto. For example, the outer covering members on the ventral and dorsal sides may be composed of separate members, and the non-skin side of the absorbent body 10 may be exposed in the crotch area, or an outer covering member for the crotch area may be provided between the ventral and dorsal outer covering members, which are separate members, to connect them.

[0059] <<Regarding the low-basis-weight portion 11s of the absorbent core 11>> The absorbent core 11 has a low basis weight section 11s, which has a lower basis weight than the surrounding area. Figure 5 is a diagram illustrating the absorbent core 11 and the crotch elastic region ER (described later), and Figure 6 is a diagram illustrating the absorbent core 11. Figure 7 is a schematic cross-sectional view of the absorbent core 11 in an extended state without the crotch elastic member 40, and Figure 8 is a schematic cross-sectional view of the absorbent core 11 in a worn state without the crotch elastic member 40. Note that in Figure 5, the low basis weight section 11sm is shown by a solid line, and in Figure 6, in addition to the absorbent core 11, the crotch elastic member 40 and the crotch elastic region ER (described later) are also shown.

[0060] Regarding the low basis weight portion 11s of the absorbent core 11, the basis weight of the absorbent core 11 refers to the basis weight of all components included in the absorbent core 11 (the weight of the components constituting the absorbent core 11 per unit area). In this embodiment, the absorbent core 11 is composed of a superabsorbent polymer (SAP) and liquid absorbent fibers such as pulp.

[0061] The low-basis-weight section 11s is a portion where the basis weight of the material constituting the absorbent core 11 is lower than that of the surrounding area (for example, adjacent areas in the left-right direction or adjacent areas in the longitudinal direction). The low-basis-weight section 11s may be a portion where the amount of material constituting the absorbent core 11 is less than that of the surrounding area, or it may be a portion that penetrates the absorbent core 11 without any material constituting the absorbent core 11 being placed there (a so-called slit). With respect to the low-basis-weight section 11s, a "portion that penetrates the absorbent core 11" is a portion where no material constituting the absorbent core 11 is placed, and the basis weight of the absorbent core 11 is 0 (zero). In this embodiment, the low-basis-weight section 11s of the absorbent core 11 does not penetrate in the thickness direction, but has a lower basis weight of the material constituting the absorbent core 11 than that of the surrounding area, and is a recessed portion that is indented from the skin side to the non-skin side in the thickness direction. As shown in Figure 6, the low-basis-weight section 11s has a crotch low-basis-weight section 11sm, a ventral low-basis-weight section 11sf, and a dorsal low-basis-weight section 11sb.

[0062] The low-basis-weight section 11sm in the crotch area is a pair of low-basis-weight sections spaced apart in the left-right direction, and is a continuous section along the longitudinal direction where the basis weight is lower than the surrounding area. When the absorbent core 11 is divided into three equal parts in the longitudinal direction, and these are designated as the ventral section 11A, the central section 11B, and the dorsal section 11C, the low-basis-weight section 11sm in the crotch area is located in the central section 11B. The pair of low-basic-weight sections 11sm in the crotch area consist of a one-side low-basic-weight section (one-side low-basic-weight section) R11sm provided on one side in the left-right direction (for example, the right side in Figure 6), and a other-side low-basic-weight section (other-side low-basic-weight section) L11sm provided on the other side in the left-right direction (for example, the left side in Figure 6).

[0063] Each pair of low-basic-weight sections 11sm below the crotch has a straight section m1 and an inclined section m2. The straight section m1 is a linear, low-basis-weight section 11s that runs along the longitudinal direction and is generally provided parallel to the longitudinal direction. The inclined portion m2 is a part that is inclined at a predetermined angle with respect to the longitudinal direction. The inclined portion m2 is inclined from the ventral side to the dorsal side in the longitudinal direction, and from the inner side to the outer side in the left-right direction. The inclined section m2 is located on the dorsal side of the straight section m1, and the dorsal portion of the straight section m1 and the ventral portion of the inclined section m2 are continuous, so the low-basic-weight section 11sm between the legs is provided as a continuous low-basic-weight section comprising the straight section m1 and the inclined section m2.

[0064] The ventral low-basis-weight sections 11sf are provided in four separate portions spaced apart from each other in the left-right direction, and are continuous portions with a lower basis weight than the surrounding area along the longitudinal direction. The ventral low-basis-weight sections 11sf are located ventrally to the crotch low-basis-weight section 11sm, are provided in the ventral portion 11A, and are spaced apart from the crotch low-basis-weight section 11sm in the longitudinal direction.

[0065] The back low basis weight sections 11sb are provided in six separate locations, spaced apart from each other in the left-right direction, and are continuous sections along the longitudinal direction where the basis weight is lower than the surrounding area. The back low basis weight sections 11sb are located on the back side of the inseam low basis weight section 11sm, in the back portion 11C, and are spaced apart from the inseam low basis weight section 11sm in the longitudinal direction.

[0066] Furthermore, the low-basis-weight portion 11s only needs to be provided in the central portion 11B of the absorbent core 11, and does not need to have a ventral low-basis-weight portion 11sf or a dorsal low-basis-weight portion 11sb. Also, the crotch low-basis-weight portion 11sm may be provided spanning the ventral portion 11A and the dorsal portion 11C.

[0067] In the region overlapping the straight portion m1 of the absorbent core 11 in the longitudinal direction, there is a first region R1 sandwiched between the straight portions m1 of a pair of low-basis-weight crotch portions 11sm, and a pair of second regions R2 provided outside the straight portions m1 of the low-basis-weight crotch portions 11sm in the left-right direction. The first region R1 is the region sandwiched between the inner ends in the left-right direction of the straight portions m1 of the low-basis-weight crotch portions 11sm, and the pair of second regions R2 are the regions from the outer ends in the left-right direction of the straight portions m1 of the low-basis-weight crotch portions 11sm to the side ends of the absorbent core 11. In the central CL in the longitudinal direction of the diaper 1, it is preferable that the length of the second region R2 in the left-right direction is longer than the length of the first region R1.

[0068] Furthermore, in the region overlapping the inclined portion m2 of the absorbent core 11 in the longitudinal direction, there is a third region R3 sandwiched between the inclined portions m2 of a pair of low-basis-weight portions 11sm, and a pair of fourth regions R4 provided outside the inclined portions m2 of the low-basis-weight portions 11sm in the left-right direction. The third region R3 is the region sandwiched between the inner ends in the left-right direction of the inclined portions m2 of the low-basis-weight portions 11sm, and the pair of fourth regions R4 are the regions from the outer ends in the left-right direction of the inclined portions m2 of the low-basis-weight portions 11sm to the side ends of the absorbent core 11. In the region overlapping the inclined portion m2 of the absorbent core 11 in the longitudinal direction, it is preferable that the left-right length of the third region R3 is longer than the left-right length of the fourth region R4.

[0069] The absorbent core 11 shown in Figures 6 and 7 is deformable when worn, as shown in Figure 8. Figure 8 illustrates the deformation of the absorbent core 11 when it is not affected by the contraction of the crotch elastic member 40. Figure 8(A) is a schematic cross-sectional view along line XX in Figure 6, Figure 8(B) is a schematic cross-sectional view along line YY in Figure 6, and Figure 8(C) is a schematic cross-sectional view along line ZZ in Figure 6.

[0070] When worn, the wearer's legs apply a force from the outside to the inside in the left-right direction, causing the absorbent core 11 to be squeezed, which makes it easier for the side edges of the absorbent core 11 to deform toward the skin. The low basis weight portion 11s is a part that is likely to become the starting point for deformation of the absorbent core 11 at this time. Therefore, as shown in Figures 8(A) to (C), the side edges of the absorbent core 11 tend to deform toward the skin, starting from the low basis weight portion 11s provided on the absorbent core 11. In particular, as in the diaper 1 of this embodiment, by providing a leak-proof wall portion 50 on the side edge of the absorbent body 10, the contraction of the leak-proof wall elastic member 51 makes it easier for deformation to occur in which the side edges of the absorbent core 11 tend to deform toward the skin. As shown in Figures 8(A) to (C), the absorbent core 11 deforms, making it easier to create a space for storing excrement in the central part of the absorbent core 11 in the left-right direction, and the side edges of the absorbent core 11 tend to act as a dam to stop the excrement, thus making it easier to suppress lateral leakage of excrement.

[0071] <<Inseam elastic member 40 and inseam elastic region ER>> The diaper 1 has one or more crotch elastic members 40 that stretch and contract along at least the longitudinal direction. The multiple crotch elastic members 40 are provided between the lower ends of the waist joints 2 in the longitudinal direction of the diaper 1 in the unfolded and extended state (crotch area 1B), and are arranged spaced apart from each other in the left-right direction. At least a portion of the crotch elastic members 40 is provided in the central part in the left-right direction. The crotch elastic members 40 are provided on the non-skin side of the absorbent core 11, and are provided in a position that overlaps with the absorbent core 11 when viewed in the thickness direction. The diaper 1 of this embodiment has multiple thread-like elastic members (thread elastic) as the crotch elastic members 40. As shown in Figure 4, the multiple crotch elastic members 40 (three thread-like elastic members) are arranged side by side with spacing in the left-right direction between the back sheet 13 and the elastic member cover sheet 17. Each crotch elastic member 40 is attached in an extended state along the longitudinal direction. In the drawings such as Figure 2 described later, only the portion of the crotch elastic member 40 that is expandable and contractible together with the diaper 1 (hereinafter also referred to as the "expandable portion") is shown. The crotch elastic member 40 may also be provided between the absorbent core 11 (core wrap sheet 18) and the back sheet 13.

[0072] The crotch area 1B of the diaper 1 is provided with a crotch elastic region ER, which is defined in the thickness direction by the stretchable portion of the crotch elastic member 40. At least a portion of the crotch elastic region ER is located between the lower ends of the waist joints 2 in the longitudinal direction of the diaper 1 in its unfolded and stretched state (crotch area 1B). The longitudinal center cte of the crotch elastic region ER is located ventrally to the longitudinal center CL of the diaper 1. The crotch elastic region ER may be contained within the crotch area 1B, or it may be positioned across the longitudinal center CL of the diaper 1. Furthermore, if the diaper 1 has multiple crotch elastic members 40, the lengths of each crotch elastic member 40 may be the same or different.

[0073] Specifically, when multiple thread-like crotch elastic members 40 are arranged with spacing between them in the left-right direction, the crotch elastic region ER is as follows. As shown in Figure 5, the crotch elastic region ER is the region between the leftmost crotch elastic member 40 and the rightmost crotch elastic member 40, and is enclosed by an imaginary line connecting the longitudinal ventral ends of the stretchable portions of each crotch elastic member 40 arranged in the left-right direction, and an imaginary line connecting the longitudinal dorsal ends of the stretchable portions of each crotch elastic member 40. In Figures 5 and 6, the crotch elastic region ER is shown by shading.

[0074] For example, as shown in Figure 5, if the lengths of the five crotch elastic members 40 are the same, the crotch elastic region ER will be rectangular. Specifically, the crotch elastic region ER shown in Figure 5 is a rectangle enclosed by the lateral ends ERa and ERb in the left-right direction and the ventral end ERc and dorsal end ERc in the longitudinal direction. The lateral end ERa of the crotch elastic region ER is the lateral end of the crotch elastic member 40 on the far left side in the left-right direction, and the lateral end ERb is the lateral end of the crotch elastic member 40 on the far right side. The ventral end ERc of the crotch elastic region ER is the ventral end of all the crotch elastic members 40, and the dorsal end ERd is the dorsal end of all the crotch elastic members 40.

[0075] Figure 9 illustrates another form of the crotch elastic region ER. As shown in Figure 9, five crotch elastic members 40 are provided in the crotch area 1B, and when the length of the three central crotch elastic members 40 is longer than that of the five crotch elastic members 40, the central part of the crotch elastic region ER in the left-right direction protrudes outward in the longitudinal direction. Specifically, the crotch elastic region ER shown in Figure 6 is roughly cross-shaped, enclosed by the lateral ends ERa and ERb in the left-right direction and the ventral end ERc and dorsal end ERc in the longitudinal direction. The lateral end ERa of the crotch elastic region ER is the lateral end of the crotch elastic member 40 on the far left side in the left-right direction, and the lateral end ERb is the lateral end of the crotch elastic member 40 on the far right side. The ventral end ERc of the crotch elastic region ER is the ventral end of the three central crotch elastic members 40, and the dorsal end ERd is the dorsal end of the three central crotch elastic members 40. Furthermore, even when the lengths of each crotch elastic member 40 are different, the crotch elastic region ER can similarly be defined by the crotch elastic members 40. If the crotch elastic member 40 is an elastic sheet (such as an elastic nonwoven fabric or elastic film), the area where the elastic sheet is located shall be defined as the crotch elastic region ER. If multiple strip-shaped elastic sheets or flat elastic bands are arranged with spacing between them in the left-right direction, the same procedure shall apply as for thread-like elastic members. In other words, the area between the leftmost end of the leftmost crotch elastic member 40 (the strip-shaped elastic sheet or flat elastic band) and the rightmost end of the rightmost crotch elastic member 40 shall be defined as the crotch elastic region ER.

[0076] The crotch elastic member 40, located in the crotch area 1B of diaper 1 and overlapping with the absorbent core 11 in the thickness direction, is bonded and integrated with the absorbent core 11 via the back sheet 13 using adhesive or the like. As a result, when diaper 1 is worn, the crotch elastic member 40 contracts in the longitudinal direction, and the absorbent core 11 is pushed towards the skin and easily deforms to conform closely to the wearer's crotch area. Therefore, the absorbent core 11 adheres well to the wearer's crotch area, making leakage of excrement less likely. Furthermore, discomfort during wear is reduced. Even after the absorbent core 11 absorbs excrement and becomes heavier, the absorbent core 11 is less likely to sag, and its conformity to the wearer's crotch area is maintained.

[0077] In particular, when the crotch elastic region ER is located in the central portion CR when the absorbent core 11 is divided into three equal parts in the left-right direction, the central portion CR of the absorbent core 11 deforms into a convex shape towards the upper side (the wearer's crotch). As a result, a gap is less likely to form between the wearer's excretory opening (e.g., the urethra) and the absorbent core 11, and it is possible to suppress the leakage of excretory fluids such as urine from the wearer's skin to the outside of the diaper 1.

[0078] <<Regarding the wearing of diaper 1>> As described above, the pants-type diaper 1, which has a pair of waist sections 1A and 1C and an absorbent core 11, has an elastic crotch region ER partitioned by an elastic crotch member 40 in the crotch area 1B, and the absorbent core 11 is provided with a pair of low-basis-weight crotch sections 11sm. In the unfolded and extended state, the low-basis-weight crotch sections 11sm are continuous along the longitudinal direction and are located in the central part 11B of the absorbent core 11 divided into three equal parts in the longitudinal direction. The elastic crotch member 40 is a member that is stretchable along the longitudinal direction and is located on the non-skin side of the absorbent core 11. In the unfolded and extended state, the longitudinal center cte of the elastic crotch region ER is located ventrally side of the longitudinal center CL of the diaper 1.

[0079] The absorbent core 11 of diaper 1 has a low basis weight section 11s that can act as a starting point for deformation, making it prone to deformation as shown in Figure 8 when worn. In diaper 1, while having an absorbent core 11 that is prone to such deformation, the crotch elastic member 40 (crotch elastic region ER) is provided in the crotch area 1B of diaper 1. Due to the longitudinal contraction of the crotch elastic member 40, in the region that overlaps with the crotch elastic region ER when viewed in the thickness direction, deformation that pushes the absorbent core 11 towards the skin is likely to occur, causing the absorbent core 11 to take on the shape shown in Figure 10. Figure 10 is a diagram illustrating the deformation of the absorbent core 11 of diaper 1 when worn. Figure 10 is a schematic cross-sectional view of the absorbent core 11 and the crotch elastic member 40 at the position of line XX in Figure 6 (the position corresponding to (A) in Figure 8).

[0080] As shown in Figure 10, the central part of the absorbent core 11 in the left-right direction (corresponding to R1 in Figure 8(A)) is prone to protruding toward the skin due to the contraction of the crotch elastic member 40. On the other hand, having a pair of low-basis-weight crotch sections 11sm, the low-basis-weight crotch sections 11sm between the central part and the side ends of the absorbent core 11 in the left-right direction act as deformation initiation points, making it easier to deform the part of the absorbent core 11 between the central part and the side ends toward the non-skin side. In other words, in the crotch area 1B, the pair of low-basis-weight crotch sections 11sm and the crotch elastic member 40 make it easier for the cross-section of the absorbent core 11 along the left-right direction to deform into a roughly W-shape when worn. By deforming the absorbent core 11 in this way, when the diaper 1 is worn, the central part in the left-right direction that protrudes toward the skin is more easily brought into contact with the excretion opening, thus making it easier to absorb excretion. In this case, the longitudinal central cte is located ventrally to the longitudinal central CL of the diaper 1, which makes it easier to bring the portion of the absorbent core 11 that protrudes towards the skin into contact with the excretion opening for urine, etc., thus making it easier to absorb urine and other excretions.

[0081] Thus, the portion of diaper 1 that overlaps with the crotch elastic region ER when viewed in the thickness direction is the part that comes closer to the wearer's excretory opening, and therefore is also the part that absorbs excrement. In conventional absorbent products such as disposable diapers, a portion that penetrates the absorbent core in the thickness direction was sometimes provided in the center of the absorbent core in the left-right direction, causing the center of the absorbent core to deform toward the skin. However, since the center in the left-right direction is the part that comes into contact with the wearer's anus, it is also the part that absorbs the most excrement. Therefore, because the part that absorbs the most excrement is the portion of the absorbent core that penetrates, there was a risk that the absorbent core and diaper 1 would not be able to properly absorb the excrement, resulting in leakage.

[0082] In contrast, in the diaper 1, when viewed in the thickness direction of the unfolded and stretched diaper 1, the average basis weight of the absorbent core 11 in the portion overlapping with the crotch elastic region ER (see Figure 5, etc.) is equal to or greater than the average basis weight of the absorbent core 11 in the crotch area 1B. The absorbent core 11 in the crotch area 1B is the region indicated by the diagonal downward-sloping line in Figure 11. Figure 11 is a diagram illustrating the absorbent core 11 in the crotch area 1B. For convenience, in Figure 11, members such as the waist elastic members 24, 25 and the leak-proof wall portion 50 are omitted. As shown in Figure 11, the average basis weight of the absorbent core 11 in the crotch area 1B in this embodiment refers to the region between the lower ends of the waist joint portions 2 in the longitudinal direction, and, when viewed in the thickness direction, the average basis weight of the absorbent core 11 that includes the region overlapping with the crotch elastic region ER and each low basis weight portion 11s.

[0083] In diaper 1, the portion that overlaps with the crotch elastic region ER, when viewed in the thickness direction, is the portion that is most likely to come into contact with the wearer's excretory opening and is the portion of the absorbent core 11 that is most likely to absorb excrement. Therefore, when viewing diaper 1 in its unfolded and stretched state in the thickness direction, if the average basis weight of the absorbent core 11 in the portion that overlaps with the crotch elastic region ER is greater than or equal to the average basis weight of the absorbent core 11 in the crotch area 1B, then more excrement can be absorbed in the portion that overlaps with the crotch elastic region ER than if the average basis weight of the absorbent core 11 in the portion that overlaps with the crotch elastic region ER were smaller than the average basis weight of the absorbent core 11 in the crotch area 1B, thus improving the absorbency of the absorbent core 11. In other words, the absorbency of the central portion in the left-right direction of the absorbent body 10 (absorbent core 11) can be improved. Furthermore, when viewing the diaper 1 in its unfolded and stretched state in the thickness direction, if the average basis weight of the absorbent core 11 in the portion overlapping with the crotch elastic region ER is greater than or equal to the average basis weight of the absorbent core 11 in the crotch area 1B, the rigidity of the portion overlapping with the crotch elastic region ER can be increased compared to when the average basis weight of the absorbent core 11 in the portion overlapping with the crotch elastic region ER is smaller than the average basis weight of the absorbent core 11 in the crotch area 1B. Therefore, even if the absorbent core 11 deforms as shown in Figure 10, the durability of the central portion of the absorbent core 11 in the left-right direction can be improved.

[0084] Furthermore, as shown in Figure 5, if the absorbent core 11 has a wide portion 11h and a narrow portion 11n, it is preferable that in the unfolded and stretched state of the diaper 1, there is a portion in the longitudinal direction where the crotch elastic region ER, the crotch low-basis-weight portion 11sm, and the narrow portion 11n overlap. The narrow portion 11n provided in the absorbent core 11 can reduce discomfort in the wearer's crotch area when worn. When the diaper 1 is worn, as shown in Figure 10, the absorbent core 11 is easily deformed so that the central portion in the left-right direction protrudes toward the skin, and the portion between the central portion and the side edges of the absorbent core 11 in the left-right direction is easily deformed toward the non-skin side. This makes it easier to bring the portion in the longitudinal direction where the crotch elastic region ER, the crotch low-basis-weight portion 11sm, and the narrow portion 11n overlap to contact the wearer's anal opening. This reduces discomfort caused by wearing diaper 1 while improving the absorbency of diaper 1 (absorbent core 11).

[0085] Regarding the crotch elastic region ER, as shown in Figure 5, when the diaper 1 is viewed in the thickness direction in the unfolded and stretched state, it is preferable that the crotch elastic member 40 does not have any portion that does not overlap with the absorbent core 11, and that the crotch elastic region ER is provided only in the central portion CR of the absorbent core 11, which is divided into three equal parts in the left-right direction. In other words, it is preferable that the crotch elastic region ER and the crotch elastic member 40 are not provided outside the central portion CR of the absorbent core 11 in the left-right direction. As a result, when the diaper 1 is worn, the absorbent core 11 is more likely to deform so that the central part in the left-right direction protrudes toward the skin, as shown in Figure 10, and the portion of the absorbent core 11 between the central part and the side edges in the left-right direction is more likely to deform toward the non-skin side. Therefore, by reducing unintended deformation for the wearer, it is possible to reduce discomfort when wearing the diaper while improving the absorbency of the diaper 1 (absorbent core 11).

[0086] Furthermore, in the unfolded and stretched state of the diaper 1, it is preferable that the crotch elastic region ER is provided between a pair of low-basis-weight crotch sections 11sm in the left-right direction. This makes it easier to deform the absorbent core 11 using the pair of low-basis-weight crotch sections 11sm as deformation starting points, and the crotch elastic region ER makes it easier to deform the absorbent core 11 so that the space between the pair of low-basis-weight crotch sections 11sm in the left-right direction faces the skin. As shown in Figure 10, this makes it easier to deform the central and side ends of the absorbent core 11 in the left-right direction toward the skin, and easier to deform the space between the central and side ends of the absorbent core 11 in the left-right direction toward the non-skin side. Therefore, when worn, it is easier to bring the diaper 1 (absorbent core 11) into contact with the excretory opening from which the wearer's urine and other excrement is excreted.

[0087] Thus, in the left-right direction, when the crotch elastic region ER is provided between a pair of crotch low-basis-weight portions 11sm (one crotch low-basis-weight portion R11sm and the other crotch low-basis-weight portion L11sm), in the unfolded and extended state, at the center CL in the longitudinal direction of the diaper 1, it is preferable that the length L2 from one end of the absorbent core 11 in the left-right direction to the left-right outer end of one crotch low-basis-weight portion R11sm in the left-right direction is longer than the length L1 from one side end ERb of the crotch elastic region ER in the left-right direction to the inner (other side) end of one crotch low-basis-weight portion R11sm (L1 <L2)。 The longitudinal center CL of diaper 1 is located in the crotch area of ​​the wearer when worn. Therefore, at the longitudinal center CL of diaper 1, the portion of length L2, from one side edge of the absorbent core 11 in the left-right direction to the outer side edge of the low-basis-weight portion R11sm in the left-right direction, is located on the outside (one side) in the left-right direction than the portion of length L1, from one side edge ERb of the crotch elastic region ER in the left-right direction to the inner edge of one side low-basis-weight portion R11sm in the crotch area. Because length L2 is longer than length L1, it is easier to provide a wider left-right side edge of the absorbent core 11 that rises towards the skin side when worn, compared to when length L1 is less than or equal to length L2. As a result, when worn, the absorbent core 11 can more easily absorb waste at its lateral edges in the central (groin) area, and it is easier to contain the waste at its lateral edges, thus making it easier to suppress leakage of waste from the diaper 1.

[0088] With respect to the crotch elastic member 40 and the crotch elastic region ER, as shown in Figure 6, it is preferable that the crotch elastic region ER (crotch elastic member 40) is not provided in the dorsal portion 11C of the absorbent core 11, which is divided into three equal parts in the longitudinal direction, when the diaper 1 of this embodiment is provided spanning from the central portion 1B to the ventral portion 11A of the absorbent core 11, which is divided into three equal parts in the longitudinal direction. The area where the crotch elastic region ER is provided makes it easier to bring the diaper 1 into contact with the wearer's skin due to the contraction of the crotch elastic member 40. When worn, the presence of the crotch elastic region ER in the central portion 11B makes it easier to bring the diaper 1 into contact with the wearer's anus, while the absence of the crotch elastic region ER in the back portion 11C makes it difficult for the back portion of the diaper 1 to adhere tightly to the wearer's body when worn. When the wearer of the diaper 1 is lying down, such as when bedridden, that is, lying on their back, it is preferable for the back portion 11C to absorb the excrement excreted in the crotch area over a wide area rather than the back portion 11 to adhere tightly to the wearer's skin and hold back the excrement. Therefore, when worn, the diaper is designed to easily absorb excrement in the groin area of ​​the wearer, while the back portion 11C is designed to create space between the wearer's body (skin) and the diaper 1, thereby facilitating the absorption of excrement over a wide area of ​​the back portion 11C.

[0089] Regarding the low-weight portion 11sm in the crotch area, as shown in Figure 6, it is preferable that, in the unfolded and extended state, the back portion 11C of the absorbent core 11 divided into three equal parts in the longitudinal direction does not have a low-weight portion 11sm in the crotch area. In other words, it is preferable that the low-weight portion 11sm in the crotch area is provided only in the central portion 11B. As a result, when the diaper 1 is worn, the absorbent core 11 is more likely to deform so that the central portion in the left-right direction protrudes toward the skin, as shown in Figure 10, and the portion between the central portion and the side edges of the absorbent core 11 in the left-right direction is more likely to deform toward the non-skin side. This makes it easier to bring the portion where the crotch elastic region ER, the low-weight portion 11sm in the crotch area, and the narrow portion 11n overlap in the longitudinal direction into contact with the wearer's anal opening. On the other hand, because the back portion 11B does not have a low-basic-weight section 11sm in the crotch area, the back portion 11B makes it easier to suppress deformation of the absorbent core 11 as shown in Figure 10, and makes it easier to conform the shape of the absorbent core 11 to the curves of the wearer's buttocks (see Figure 8(C)). In this embodiment, the diaper 1 has a low-basis-weight portion 11sb on the back side of the back portion 11C, but it is not continuous with the low-basis-weight portion 11sm below the crotch and is separate from the low-basis-weight portion 11sm below the crotch. Therefore, it is a different low-basis-weight portion 11s from the low-basis-weight portion 11sm below the crotch, and thus has a different deformation starting point in the absorbent core 11.

[0090] Furthermore, as shown in Figure 6, etc., in the unfolded and extended state of the diaper 1, it is preferable that the ventral end e40f of the crotch elastic member 40 located on the ventral side is located on the ventral side of the ventral end e11sm of the crotch low-basis-weight section 11sm located on the ventral side. In this embodiment of the diaper 1, the ventral ends of the multiple elastic members 40 are all located at the same position (end e40f), but as shown in Figure 9, if the lengths (or positions) of the multiple crotch elastic members 40 are different, the end of the crotch elastic member 40 located on the ventral side among the multiple crotch elastic members 40 is defined as end e40f. Similarly, if the ventral ends of a pair of crotch low-basis-weight sections 11sm are located at different positions, the position located on the ventral side among the ventral ends of the pair of crotch low-basis-weight sections 11sm is defined as end e11sm.

[0091] As described above, the low-weight portion 11sm in the crotch area is a part that is prone to deformation. Therefore, deformation is likely to start not only at the side edges of the low-weight portion 11sm in the crotch area, but also at the ventral edge e11sm. For this reason, by positioning the ventral edge e40f of the crotch elastic member 40 ventrally further than the ventral edge e11sm of the low-weight portion 11sm in the crotch area, when a longitudinal contraction force acts on the crotch elastic member 40 positioned ventrally further than the low-weight portion 11sm in the crotch area, the ventral edge e11sm of the low-weight portion 11sm in the crotch area becomes more prone to deformation, bending along the left-right direction. This makes it easier to deform the ventral portion of the absorbent core 11 to conform to the shape of the wearer's body (abdomen), making it easier to fit the diaper 1 (absorbent core 11).

[0092] Each of the pair of low-basic-weight sections 11sm below the crotch can be shaped in any way. As shown in Figure 6, it is preferable that a pair of low-basic-weight sections 11sm below the crotch each have a straight section m1 and an inclined section m2. The straight section m1 is preferably a straight line along the longitudinal direction, and the inclined section m2 is preferably inclined from the ventral side to the dorsal side in the longitudinal direction, and from the inner side to the outer side in the left-right direction. This inclined section m2 is provided on the dorsal side of the straight section m1, and the straight section m1 and the inclined section m2 are continuous. Since the length in the left-right direction between the low-basic-weight sections 11sm is longer in the portion where the inclined section m2 is provided than in the portion where the straight section m1 is provided, the absorbency of the portion on the dorsal side of the straight section m1 can be improved. Thus, the diaper 1, which has a low-basic-weight section 11sm with a straight section m1 and an inclined section m2, and an elastic member 40 in the crotch area, improves the absorption of excrement in the crotch area and the area behind the crotch area of ​​the wearer, while the shape of the inclined section m2 makes it easier to deform the absorbent core 11 to conform to the shape of the wearer's buttocks, thereby improving the fit of the diaper 1.

[0093] Preferably, both ends of the absorbent core 11 have core inclined portions k11 that are inclined from the ventral side to the dorsal side in the longitudinal direction, and from the inner side to the outer side in the left-right direction. Furthermore, when the low-basis-weight portion 11sm below the crotch has a straight portion m1 and an inclined portion m2, it is preferable that, in the unfolded and extended state, on one side in the left-right direction (for example, the right side in Figure 6), the inclined portion m2 of the low-basis-weight portion 11sm below the crotch is positioned to overlap with the core inclined portion k11 of the absorbent core 11 in the longitudinal direction. Similarly, in the unfolded and extended state, it is preferable that, on the other side in the left-right direction (for example, the left side in Figure 6), the inclined portion m2 of the low-basis-weight portion 11sm is positioned to overlap with the core inclined portion k11 of the absorbent core 11 in the longitudinal direction. As a result, when wearing diaper 1, the absorption of excrement in the groin area and the area behind the groin is improved, while the inclined portion m2 and core inclined portion k11 make it easier to deform the absorbent core 11 to conform to the shape of the wearer's buttocks, thereby improving the fit of diaper 1.

[0094] As described above, it is preferable that the diaper 1 has an absorbent body 10 equipped with an absorbent core 11 and a leak-proof wall portion 50. Furthermore, it is preferable that it has a pair of leg-around elastic members 52 (side elastic members) provided on both the left and right outer sides of the crotch elastic member 40. The leg-around elastic members 52 are expandable and contractible members that can expand and contract along the longitudinal direction. In this embodiment, the leg-around elastic members 52 of the diaper 1 are arranged with two thread-like elastic members (thread elastic) that are shorter in length in the longitudinal direction than the leak-proof wall elastic member 51, and as shown in Figure 4, in the thickness direction, they are provided on the non-skin side of the absorbent core 11 and on the skin side of the back sheet 13. As shown in Figure 10, etc., in the unfolded and extended state, it is preferable that at least a part of the leg-around elastic members 52 is provided between the position of the starting point e50 of the leak-proof wall portion 50 in the left and right direction and the side end of the absorbent core 11 at the center CL in the longitudinal direction of the diaper 1 on one side in the left and right direction. In other words, it is preferable that the leak-proof wall portion 50 is located in a position that does not overlap with the fixing portion 50b of the leak-proof wall portion 50 and the absorbent core 11 at the center CL in the longitudinal direction of the diaper 1 when it is unfolded and extended. This makes it easier to shorten the absorbent body 10 in the longitudinal direction at the wearer's crotch area due to the contraction of the leg elastic member 52, and thus makes it easier to raise the leak-proof wall portion 50. As a result, it becomes easier to suppress lateral leakage of excrement from the diaper 1.

[0095] When the diaper 1 has leg elastic members 52, it is preferable that the dorsal end e52 of the leg elastic member 52 is located dorsally beyond the dorsal end b11sm of the crotch low-weight portion 11sm, as shown in Figure 5. The crotch low-weight portion 11sm provided in the absorbent core 11 facilitates deformation of the absorbent core 11, and by having the dorsal end e52 of the leg elastic member 52 located dorsally beyond the dorsal end b11sm of the crotch low-weight portion 11sm, the contraction of the leg elastic member 52 makes it easier to bring the diaper 1 (absorbent core 11) into contact with the wearer's skin from the crotch towards the back, compared to when the dorsal end e52 of the leg elastic member 52 is located skin-side from the dorsal end b11sm of the crotch low-weight portion 11sm, thereby improving the fit of the diaper 1.

[0096] Furthermore, if the diaper 1 has leg elastic members 52 and the absorbent core 11 has a wide portion 11h which is the widest in the left-right direction and a narrow portion 11n which is narrower in the left-right direction than the wide portion 11h, then, in the longitudinal direction of the unfolded and extended diaper 1 (absorbent body 10), as shown in Figure 5, it is preferable that the leg elastic members 52 do not overlap with the absorbent core 11 in the thickness direction in the region N which overlaps with the shortest part of the narrow portion 11n in the left-right direction. As a result, the low-basis-weight portion 11sm in the crotch area of ​​the absorbent core 11 facilitates deformation of the absorbent core 11, and when viewed in the thickness direction, the leg-around elastic member 52 does not overlap with the portion N that is shortest in the left-right direction of the absorbent core 11. This makes it easier for the diaper 1 (absorbent core 11) to come into contact with the wearer's skin from the crotch area toward the back of the wearer due to the contraction of the leg-around elastic member 52, compared to when the leg-around elastic member 52 overlaps with portion N, thereby improving the fit of the diaper 1.

[0097] Furthermore, as shown in Figure 12, the absorbent core 11 may have a compressed portion 80 that is compressed in the thickness direction. Figure 12 is a diagram illustrating an absorbent core 11 having a compressed portion 80. The absorbent core 11 shown in Figure 12 has multiple compression sections 80. The multiple compression sections 80 are arranged in a so-called zigzag pattern, with repeated indentations and recesses along the longitudinal direction and in the left-right direction, and the overall structure is a grid. The compression sections 80 may be formed by compressing only the absorbent core 11 in the thickness direction, or they may be formed by compressing together with the core wrap sheet 18 or top sheet 12. The compression sections 80 can be any part that is denser than the surrounding area when compressed in the thickness direction, and may be a part that is recessed from the skin side to the non-skin side, or a part that is recessed from the non-skin side to the skin side. By providing the absorbent core 11 with compression sections 80, the rigidity and durability of the absorbent core 11 can be improved, and the diffusion of absorbed excrement can be improved. In the form shown in Figure 12, the compression sections 80 are arranged in a grid pattern, but this is not the only option. The shape and arrangement of the compression sections 80 can be changed as desired. However, it is preferable that the compression section 80 is shaped to follow the longitudinal direction in order to spread the excrement in the longitudinal direction.

[0098] As shown in Figure 12, when the absorbent core 11 has multiple compression sections 80, it is preferable that when the unfolded and extended diaper 1 is viewed in the thickness direction, one side of the crotch low-basis-weight section R11sm in the left-right direction has a portion that overlaps with the compression section 80, and the other side of the crotch low-basis-weight section L11sm in the left-right direction has a portion that overlaps with the compression section 80. The low-basis-weight section 11sm is a part of the absorbent core 11 with a lower basis weight than the surrounding area, and therefore has low rigidity. In contrast, by having the one side crotch low-basis-weight section R11sm and the other side low-basis-weight section L11sm each have portions that overlap with the compression section 80, the rigidity of the low-basis-weight section 11sm (R11sm, L11sm) and the absorbent core 11 can be improved. Therefore, as described above, the low basis weight section 11sm and the crotch elastic member 40 promote deformation of the absorbent core 11 while reducing the risk of the absorbent core 11 losing its shape. This improves the durability of the absorbent core 11 and makes it easier to suppress the decrease in its absorbency.

[0099] As shown in Figure 12, when the absorbent core 11 has a compression section 80, it is preferable that when the diaper 1 in its unfolded and stretched state is viewed in the thickness direction, there is a portion where the crotch elastic region ER and the compression section 80 overlap. By having a portion where the crotch elastic region ER and the compression section 80 overlap when viewed in the thickness direction, the rigidity of the absorbent core 11 that overlaps with the portion where the crotch elastic region ER is provided is improved. Therefore, when worn, the contraction of the crotch elastic member 40 deforms the absorbent core 11 so that the diaper 1 (absorbent core 11) can be brought closer to the wearer's excretory opening, while reducing the risk of the shape of the absorbent core 11 in the portion where the crotch elastic region ER is provided collapsing. This improves the durability of the absorbent core 11 and makes it easier to suppress the decrease in the absorbency of the absorbent core 11.

[0100] Furthermore, as shown in Figure 13, when viewing the unfolded and extended diaper 1 in the thickness direction, the area outside the pair of low-basis-weight sections 11sm in the left-right direction within the region overlapping with the absorbent core 11 may be colored, and the area between the pair of low-basis-weight sections 11sm in the left-right direction within the region overlapping with the absorbent core 11 may be white. Figure 13 is a modified example of the absorbent body 10. In Figure 13, for convenience, the fixing parts 50a, 50b, etc. of the leak-proof wall section 50 are omitted, and the low-basis-weight sections 11sm are shown with solid lines. In the modified example shown in Figure 13, the area outside the pair of low-basis-weight sections 11sm is blue, and the area between the pair of low-basis-weight sections 11sm in the left-right direction within the region overlapping with the absorbent core 11 is white. The color of the part outside the pair of low-basis-weight sections 11sm can be arbitrarily set as long as it is "colored".

[0101] As described above, the diaper 1, by having a low-weight section 11sm in the crotch and an elastic member 40 in the crotch, is easily deformed so that the central part in the left-right direction of the absorbent core 11 faces the skin, and the area between the central part in the left-right direction and the side edges faces the non-skin side (see Figure 10). Also, when the diaper 1 is viewed from the skin side, the gaze is usually drawn to the central part in the left-right direction. In contrast, when wearing the diaper 1 equipped with the absorbent body 10 (diaper 1) as shown in Figure 13, the part corresponding to the side edges of the absorbent core 11 is colored (blue), so that the absorbent core 11 is provided not only between the white low-weight sections 11sm in the crotch, but also in the parts outside the pair of low-weight sections 11sm in the left-right direction, making it easier for the wearer to recognize that the parts outside the pair of low-weight sections 11sm in the crotch are also parts that can absorb excrement.

[0102] "Colored" refers to any color other than colorless, transparent, and white. On the other hand, "white" refers to colors such as "N9.5" in the Munsell color system or "255,255,255" in the RGB color space (so-called pure white), as well as colors whose color difference from pure white is less than 12. For measuring the color difference of white, for example, a Konica Minolta CR-300 can be used as a color difference meter, and a C light source (International Commission on Illumination (CIE) standard) can be used as the light source of the measuring instrument. In this case, the diameter of the measurement window of the measuring instrument is 40 mm. The color difference is ΔL, Δa, and Δb in the (L*a*b*) color space relative to a white reference plate. The color difference relative to a white reference plate can be calculated by measuring the lab value of the white reference plate and the lab value of the target sample, respectively. The white reference plate is set to lab0 at (X93.19, Y95.20, Z112.28). Here, L is a value that indicates brightness, and a and b are the planar coordinates of chromaticity. If the Lab values ​​of the white reference plate are L0, a0, and b0, and the Lab values ​​of the target sample are L1, a1, and b1, then ΔL can be calculated as ΔL=L0-L1, Δa=a0-a1, and Δb=b0-b1.

[0103] Furthermore, the back of the diaper 1 may have a buttock area below the back waist circumference portion 1C in the vertical direction, which covers the wearer's buttocks, and the buttock area may be equipped with an elastic member such as a buttock elastic member 26. The buttock elastic member 26 shown in Figure 2, etc., is arranged substantially parallel to the left-right direction, but the buttock area may be provided with a thread-like or sheet-like curved elastic member (not shown) that has a curved portion along the outer edge of the buttock area. Furthermore, it is preferable that, in the longitudinal direction of the diaper 1 in its unfolded and extended state, the buttock elastic member 26 or the curved elastic member is not positioned to overlap with the crotch elastic member 40.

[0104] ===Second Embodiment=== Figure 14 is a schematic plan view of the diaper 100 in its unfolded and extended state, as seen from the skin side. The basic configuration of the disposable diaper 100 (diaper 100) of the second embodiment is the same as that of the disposable diaper 1 of the first embodiment described above, but the configuration of the low basis weight section 11sm differs from that of the diaper 1 of the first embodiment. For the diaper 100 of the second embodiment, parts common to the configuration of the first embodiment are given the same reference numerals, etc., and detailed explanations are omitted. In addition, some of the features of the diaper 1 of the first embodiment described above are also applicable to the diaper 1 of the second embodiment, and the details are omitted.

[0105] The absorbent core 11 of diaper 100 has a low basis weight portion 11s, similar to diaper 1 in the first embodiment, where the basis weight is less than that of the surrounding area. As shown in Figure 14, the low basis weight portion 11s of diaper 100 has a low basis weight portion 11sm at the crotch and a low basis weight portion 11sf on the ventral side.

[0106] The low-basis-weight section 11sm in the crotch area is a pair of low-basis-weight sections spaced apart in the left-right direction, and is a continuous section along the longitudinal direction where the basis weight is lower than the surrounding area. When the absorbent core 11 is divided into three equal parts in the longitudinal direction, and these are designated as the ventral section 11A, the central section 11B, and the dorsal section 11C, in order from the ventral side to the dorsal side, the low-basis-weight section 11sm in the crotch area is provided in the central section 11B and the ventral section 11A. The pair of low-basic-weight sections 11sm in the crotch area consist of a one-side low-basic-weight section R11sm provided on one side in the left-right direction (for example, the right side in Figure 6) and a other-side low-basic-weight section L11sm provided on the other side in the left-right direction (for example, the left side in Figure 6).

[0107] Each of the crotch area low-weight portions 11sm of diaper 100 has a curved portion wn that protrudes outward in the left-right direction. The apex P of this curved portion wn of the crotch area low-weight portion 11sm is located at the outermost point of the crotch area low-weight portion 11sm in the left-right direction.

[0108] The ventral low-basis-weight portion 11sf is a mountain-shaped low-basis-weight portion that protrudes toward the ventral side in the longitudinal direction. It is located ventrally to the crotch low-basis-weight portion 11sm and is provided in the ventral portion 11A.

[0109] Having a low basis weight section 11s (11sm, 11sf) makes it easier to deform the absorbent core 11 into a predetermined shape, thereby improving absorbency and fit when worn.

[0110] Furthermore, the diaper 100, like the diaper 1 of the first embodiment, has one or more crotch elastic members 40 that stretch and contract along at least the longitudinal direction. The multiple crotch elastic members 40 are provided between the lower ends of the waist joints 2 in the longitudinal direction of the diaper 100 in the unfolded and extended state (crotch area 1B), and are arranged spaced apart from each other in the left-right direction. At least a portion of the crotch elastic members 40 is provided in the central part in the left-right direction. The crotch elastic members 40 are provided on the non-skin side of the absorbent core 11, and are provided in a position that overlaps with the absorbent core 11 when viewed in the thickness direction. The diaper 100 of this embodiment has multiple thread-like elastic members (thread elastic) as the crotch elastic members 40.

[0111] The crotch area 1B of the diaper 100 is provided with a crotch elastic region ER, which is defined by the stretchable portion of the crotch elastic member 40 when viewed in the thickness direction. At least a portion of the crotch elastic region ER is located between the lower ends of the waist joint portions 2 in the longitudinal direction of the diaper 100 in its unfolded and stretched state (crotch area 1B). The longitudinal center of the crotch elastic region ER is located ventrally to the longitudinal center CL of the diaper 1.

[0112] The absorbent core 11 of diaper 100 is made more prone to protruding towards the skin in the left-right direction due to the low-basic-weight portion 11sm of the crotch and the elastic member 40 of the crotch, and the portion of the absorbent core 11 between the central portion and the side edges in the left-right direction is made more prone to deformation toward the non-skin side. In other words, in the crotch area 1B, the pair of low-basic-weight portions 11sm of the crotch and the elastic member 40 of the crotch make it easier for the cross-section of the absorbent core 11 along the left-right direction to deform into a roughly W shape when worn (see Figure 10). By deforming the absorbent core 11 in this way, when diaper 100 is worn, the central portion in the left-right direction that protrudes toward the skin is made more prone to contacting the excretion opening of the excrement, thus making it easier to absorb excrement. In this case, the longitudinal center of the crotch elastic region ER is located ventrally to the longitudinal center CL of the diaper 100, which makes it easier to bring the portion of the absorbent core 11 that protrudes towards the skin into contact with the excretion opening for urine, etc., thus making it easier to absorb urine and other excretions.

[0113] Furthermore, when viewing the diaper 100 in its unfolded and stretched state in the thickness direction, the average basis weight of the absorbent core 11 in the portion overlapping with the crotch elastic region ER is equal to or greater than the average basis weight of the absorbent core 11 in the crotch area 1B.

[0114] In diaper 100, the portion overlapping with the crotch elastic region ER, when viewed in the thickness direction, is the portion that is most likely to come into contact with the wearer's anus and is the portion of the absorbent core 11 that most easily absorbs waste. Therefore, when viewing diaper 100 in its unfolded and stretched state in the thickness direction, if the average basis weight of the absorbent core 11 in the portion overlapping with the crotch elastic region ER is greater than or equal to the average basis weight of the absorbent core 11 in the crotch area 1B, then more waste can be absorbed in the portion overlapping with the crotch elastic region ER than if the average basis weight of the absorbent core 11 in the portion overlapping with the crotch elastic region ER were smaller than the average basis weight of the absorbent core 11 in the crotch area 1B, thus improving the absorbency of the absorbent core 11. In other words, the absorbency of the central portion in the left-right direction of the absorbent body 10 (absorbent core 11) can be improved. Furthermore, when viewing the diaper 100 in its unfolded and stretched state in the thickness direction, if the average basis weight of the absorbent core 11 in the area overlapping with the crotch elastic region ER is greater than or equal to the average basis weight of the absorbent core 11 in the crotch area 1B, the rigidity of the area overlapping with the crotch elastic region ER can be increased compared to when the average basis weight of the absorbent core 11 in the area overlapping with the crotch elastic region ER is smaller than the average basis weight of the absorbent core 11 in the crotch area 1B. Therefore, even if the central part of the absorbent core 11 in the left-right direction deforms to protrude towards the skin when worn, the durability of the central part of the absorbent core 11 in the left-right direction can be improved. In addition, the deformation of the absorbent core 11 can improve the fit of the diaper 100 when worn.

[0115] Regarding the crotch elastic region ER, as shown in Figure 14, in the unfolded and extended state, the crotch elastic region ER (crotch elastic member 40) may be provided up to the dorsal portion 11C, which is one of the three equal parts obtained by dividing the absorbent core 11 in the longitudinal direction. By providing the crotch elastic region ER from the central portion 11B to the dorsal portion 11C, the contraction of the crotch elastic region ER (crotch elastic member 40) makes it easier to make the diaper 1 adhere closely to the wearer's skin from the crotch to the back. When the wearer is able to move, such as walking, it is desirable that the diaper 1 fits snugly to the wearer's skin and is not easily visible. Therefore, by providing the crotch elastic region ER from the central portion 11B to the dorsal portion 11C, it is easier to fit the diaper 1 from the crotch to the back, making it difficult to see the presence of the diaper 1 from the outside.

[0116] Furthermore, in the unfolded and stretched state of the diaper 100, as shown in Figure 14, it is preferable that the crotch elastic region ER is provided between a pair of low-basis-weight crotch sections 11sm in the left-right direction. This makes it easier to deform the absorbent core 11 using the pair of low-basis-weight crotch sections 11sm as deformation starting points, and the crotch elastic region ER makes it easier to deform the absorbent core 11 so that the space between the pair of low-basis-weight crotch sections 11sm in the left-right direction faces the skin. This makes it easier to deform the central part of the absorbent core 11 in the left-right direction toward the skin, and easier to deform the space between the central part and the side edges of the absorbent core 11 so that it faces away from the skin. Therefore, when worn, it is easier to bring the diaper 100 (absorbent core 11) into contact with the excretory opening from which the wearer's urine and other excrement is excreted.

[0117] In the left-right direction, when the crotch elastic region ER is provided between a pair of crotch low-basis-weight portions 11sm (one crotch low-basis-weight portion R11sm and the other crotch low-basis-weight portion L11sm), in the unfolded and extended state, at the center CL in the longitudinal direction of the diaper 1, it is preferable that the length L4 from one end of the absorbent core 11 in the left-right direction to the left-right outer end of one crotch low-basis-weight portion R11sm in the left-right direction is longer than the length L3 from one side end ERb of the crotch elastic region ER in the left-right direction to the inner (other side) end of one crotch low-basis-weight portion R11sm (L3 <L4)。 In the longitudinal center CL of diaper 1, the portion of length L4, from one side edge of the absorbent core 11 in the left-right direction to the outer side edge of the low-basis-weight portion R11sm in the left-right direction, is located on the outside (one side) in the left-right direction, compared to the portion of length L3, from one side edge ERb of the crotch elastic region ER to the inner edge of one side low-basis-weight portion R11sm in the crotch. Because length L4 is longer than length L3, when worn, it is easier to provide a wider left-right side edge of the absorbent core 11 that rises towards the skin side than when length L3 is less than or equal to length L4. As a result, in the central part (crotch area) when worn, it is easier to contain excrement at the side edge of the absorbent core 11 and to absorb excrement at the side edge of the absorbent core 11, thus making it easier to suppress lateral leakage of excrement from diaper 100.

[0118] Furthermore, as shown in Figure 14, when a pair of low-basis-weight sections 11sm each have a curved section wn that protrudes outward in the left-right direction, it is preferable that in the unfolded and extended state of the diaper 100, at the apex P position of the curved section wn in the longitudinal direction, the length L6 from one end of the absorbent core 11 in the left-right direction to the outer (one side) end of the low-basis-weight section R11sm in the left-right direction is longer than the length L5 from one side end ERb of the elastic area ER in the left-right direction to the inner (other side) end of one low-basis-weight section R11sm (L5 <L6)。 The position of the apex P of the curved portion wn in the longitudinal direction is the part where the length L6 from one side end of the absorbent core 11 in the left-right direction to the outer side end of the one side low-basis-weight portion R11sm in the left-right direction is shorter. However, even at this position of the apex P in the longitudinal direction, the length L6 from one side end of the absorbent core 11 in the left-right direction to the outer side end of the one side low-basis-weight portion R11sm in the left-right direction is longer than the length L5 from one side end ERb of the inseam elastic region ER in the left-right direction to the inner side end of the one side low-basis-weight portion R11sm in the left-right direction. Therefore, when worn, it is easier to provide a wider left-right side end of the absorbent core 11 that rises towards the skin side of the absorbent core 11 than when length L5 is less than or equal to length L6. As a result, in the central part (groin area) when worn, the side edges of the absorbent core 11 can more easily contain excrement, and the side edges of the absorbent core 11 can also more easily absorb excrement, thus making it easier to suppress lateral leakage of excrement from the diaper 100.

[0119] ===Other=== The embodiments described above are provided to facilitate understanding of the present invention and are not intended to limit its interpretation. The present invention may be modified and improved without departing from its spirit, and it goes without saying that equivalents thereof are included. [Explanation of Symbols]

[0120] 1,100 diapers (disposable pull-up diapers, absorbent pull-up items), 1A Ventral girth area (girth area), 1B Inseam, 1C Dorsal side of the torso (torso), 2. Joint around the torso (joint), 10 Absorbent body, 11 Absorbent core, 11s low basis weight part, 11sf Ventral low basis weight part, 11sm Inseam low basis weight part (low basis weight part), R11sm One side inseam low basis weight part (one side low basis weight part), L11sm Other side inseam low basis weight part (other side low basis weight part), 11sb Dorsal low basis weight part, 12 top sheets, 13 back seats, 16 side seats, 17 Elastic member cover sheet, 20 Exterior components, 21 Ventral outer layer sheet, 22 Dorsal outer layer sheet, 23 Inner layer sheet, 24. Ventral circumferential elastic member 25. Elastic member around the back of the torso, 26. Buttock elastic member, 31 cover sheet, 32 cover sheet, 40. Inseam elastic member, 50 Leakage prevention wall section, 51 Leak-proof wall elastic member, 52 Leg elastic members (side elastic members), ER (Elevator Range) - Inseam Elastic Region

Claims

1. A pair of torso sections joined at joints on both sides, It has a crotch area below the aforementioned joint, A pant-type absorbent article equipped with an absorbent core, In the unfolded and extended state, It has longitudinal, left-right, and thickness directions that intersect with each other, The crotch area is provided on the non-skin side of the absorbent core and has one or more crotch elastic members provided at least along the longitudinal direction. At least a portion of the crotch elastic member is provided in the central part in the left-right direction, The crotch area is provided with an elastic crotch region defined by the crotch elastic member, The longitudinal center of the crotch elastic region is located ventrally to the longitudinal center of the pant-type absorbent article. The absorbent core is It has a superabsorbent polymer, The absorbent core is provided with a pair of low-basis-weight sections, which are continuous along the longitudinal direction and located in the central part of the three equal parts obtained by dividing the absorbent core in the longitudinal direction, and which have a lower basis weight than the surrounding area. The average basis weight of the absorbent core in the portion overlapping with the crotch elastic region when viewed in the thickness direction is equal to or greater than the average basis weight of the absorbent core in the crotch area. A pant-type absorbent article characterized by the following features.

2. The absorbent pant-type article according to claim 1, In the aforementioned unfolded and extended state, The absorbent core has a wide portion that is the longest in the left-right direction and a narrow portion that is shorter in the left-right direction than the wide portion. A pant-type absorbent article characterized in that, in the longitudinal direction, it has a portion where the crotch elastic region, the low basis weight portion, and the narrow width portion overlap.

3. A pant-type absorbent article according to claim 1 or 2, In the aforementioned unfolded and extended state, Viewed in the thickness direction, the crotch elastic member does not have any portion that does not overlap with the absorbent core. The aforementioned crotch elastic region is provided only in the central portion of the three equal parts obtained by dividing the absorbent core in the left-right direction, and is characterized in that the pants-type absorbent article is provided in this manner.

4. A pant-type absorbent article according to claim 1 or 2, In the aforementioned unfolded and extended state, A pant-type absorbent article characterized in that the low basis weight portion is not provided in the back portion of the absorbent core, which is divided into three equal parts in the longitudinal direction.

5. A pant-type absorbent article according to claim 1 or 2, The absorbent core has a plurality of compressed portions that are compressed in the thickness direction, The pair of low-basis-weight sections each have a one-side low-basis-weight section provided on one side in the left-right direction and a other-side low-basis-weight section provided on the other side in the left-right direction. In the aforementioned unfolded and extended state, Viewed in the thickness direction, The aforementioned low basis weight section on one side has a portion that overlaps with the compression section, The pants-type absorbent article is characterized in that the other low-basis-weight portion has a portion that overlaps with the compressed portion.

6. A pant-type absorbent article according to claim 1 or 2, The absorbent core has a compressed portion that is compressed in the thickness direction, In the aforementioned unfolded and extended state, A pant-type absorbent article characterized in that, when viewed in the thickness direction, it has a portion where the crotch elastic region and the compression portion overlap.

7. A pant-type absorbent article according to claim 1 or 2, In the aforementioned unfolded and extended state, A pant-type absorbent article characterized in that the crotch elastic region is provided up to the back portion of the absorbent core, which is divided into three equal parts in the longitudinal direction.

8. A pant-type absorbent article according to claim 1 or 2, In the aforementioned unfolded and extended state, A pant-type absorbent article characterized in that the crotch elastic region is not provided in the dorsal portion of the absorbent core, which is divided into three equal parts in the longitudinal direction.

9. A pant-type absorbent article according to claim 1 or 2, In the aforementioned unfolded and extended state, Viewed in the thickness direction, In the region overlapping with the absorbent core, the area outside the pair of low-basis-weight portions in the left-right direction is colored. A pant-type absorbent article characterized in that, in the region overlapping with the absorbent core, the area between the pair of low-basis-weight portions in the left-right direction is white.

10. A pant-type absorbent article according to claim 1 or 2, In the aforementioned unfolded and extended state, A pant-type absorbent article characterized in that the ventral end of the crotch elastic member located on the ventral side is located further ventral than the ventral end of the low-basis-weight portion located on the ventral side.

11. A pant-type absorbent article according to claim 1 or 2, In the aforementioned unfolded and extended state, In the left-right direction, the crotch elastic region is provided between the pair of low-basis-weight portions, characterized in that it is a pair of pants-type absorbent article.

12. The absorbent pant-type article according to claim 11, The pair of low-basis-weight sections each have a one-side low-basis-weight section provided on one side in the left-right direction and a other-side low-basis-weight section provided on the other side in the left-right direction. In the aforementioned unfolded and extended state, At the center of the aforementioned pant-type absorbent article in the longitudinal direction, A pant-type absorbent article characterized in that the length from one side edge in the left-right direction of the crotch elastic region to the inner edge in the left-right direction of the low-basis-weight portion on one side is longer than the length from one side edge in the left-right direction of the absorbent core to the outer edge in the left-right direction of the low-basis-weight portion on one side.

13. The pant-type absorbent article according to claim 12, Each of the pair of low-basis-weight sections has a curved portion that protrudes outward in the left-right direction, The apex of the curved portion is located at the outermost point in the left-right direction of the low basis weight portion. In the aforementioned unfolded and extended state, At the apex position of the curved portion in the longitudinal direction, A pant-type absorbent article characterized in that the length from one side edge in the left-right direction of the crotch elastic region to the inner edge in the left-right direction of the low-basis-weight portion on one side is longer than the length from one side edge in the left-right direction of the absorbent core to the outer edge in the left-right direction of the low-basis-weight portion on one side.

14. A pant-type absorbent article according to claim 1 or 2, In the aforementioned unfolded and extended state, The pair of low basis weight sections are, The straight section along the longitudinal direction, It has an inclined portion that slopes from the ventral side to the dorsal side in the longitudinal direction, and from the inner side to the outer side in the left-right direction, The pant-type absorbent article is characterized in that the inclined portion is provided on the back side of the straight portion, and the straight portion and the inclined portion are continuous.

15. The absorbent pant-type article according to claim 14, In the aforementioned unfolded and extended state, Both ends of the absorbent core each have a core inclined portion that slopes from the ventral side to the dorsal side in the longitudinal direction, and from the inner side to the outer side in the left-right direction. On one side in the left-right direction, the inclined portion is provided in a position that overlaps with the core inclined portion in the longitudinal direction. A pant-type absorbent article characterized in that, on the other side in the left-right direction, the inclined portion is provided in a position that overlaps with the core inclined portion in the longitudinal direction.

16. A pant-type absorbent article according to claim 1 or 2, Having an absorbent body equipped with the aforementioned absorbent core, The absorbent body has a pair of leak-proof walls on its left and right sides that can stand upright on the skin side, It has a pair of side elastic members that are stretchable along the longitudinal direction and are provided on both the left and right outer sides of the crotch elastic member, A pant-type absorbent article characterized in that, at the center of the longitudinal direction of the pant-type absorbent article on one side in the left-right direction, at least a portion of the side elastic member is provided between the position of the starting point of the leak-proof wall portion in the left-right direction and the side end of the absorbent core.

17. A pant-type absorbent article according to claim 1 or 2, It has a pair of side elastic members that are stretchable along the longitudinal direction and are provided on both the left and right outer sides of the crotch elastic member, A pant-type absorbent article characterized in that the back end of the side elastic member is provided further back than the back end of the low basis weight portion.

18. A pant-type absorbent article according to claim 1 or 2, It has a pair of side elastic members that are stretchable along the longitudinal direction and are provided on both the left and right outer sides of the crotch elastic member, The absorbent core has a wide portion that is the longest in the left-right direction and a narrow portion that is shorter in the left-right direction than the wide portion. In the longitudinal direction, the side elastic member does not overlap with the absorbent core in the region of the narrowest part of the width that has the shortest length in the left-right direction, as viewed in the thickness direction.

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