Absorbent panty-type items

Abstract

This invention relates to a pant-type absorbent article that is comfortable around the abdomen and has a dorsal extension that prevents it from slipping down. [Solution] The pant-type absorbent article comprises an outer body having an abdominal portion, a dorsal portion, and a crotch portion. The dorsal portion has a dorsal extension portion and a dorsal main body portion. The outer body has leg elastics. The leg elastics consist of a dorsal leg elastic, which is positioned on the dorsal and crotch portions, and a ventral leg elastic, which is positioned on the abdominal and crotch portions. In the unfolded and extended state, the dorsal leg elastics and the ventral leg elastics have portions that are inclined with respect to the longitudinal direction. In the unfolded and extended state, the shortest distance from the dorsal waist end to the dorsal leg elastic is longer than the shortest distance from the ventral waist end to the ventral leg elastic. The ventral portion includes the ventral waist end and has a ventral waist region that extends across the entire lateral width of the ventral portion, having the same longitudinal length as the dorsal extension portion. The dorsal extension portion has higher rigidity than the ventral waist region.

Description

TECHNICAL FIELD

[0001] The present invention relates to a pants-type absorbent article such as a disposable diaper.

BACKGROUND ART

[0002] Infants have a characteristic body shape with a protruding abdomen. Since the abdominal circumference varies significantly before and after feeding, it is preferable that the pants-type absorbent article does not excessively tighten the abdomen and does not make the abdomen feel uncomfortable. However, if the contraction stress of the elastic body around the abdomen of the pants-type absorbent article is simply reduced, the diaper may slip off due to the movement of the infant, leading to leakage of excreta.

[0003] A pants-type absorbent article generally includes an absorbent main body, an exterior body, and side seals where the ventral exterior body and the dorsal exterior body are joined at side end portions. The waist portion of the pants-type absorbent article is formed by joining the ventral exterior body and the dorsal exterior body via the side seals.

[0004] Patent Documents 1 and 2 disclose pants-type absorbent articles having a dorsal extension portion on the waist side of the dorsal exterior body. With such a configuration, for example, excreta such as loose stool can be prevented from leaking from the dorsal side. For example, young infants often lie on their backs and tend to pass loose stool, so providing a dorsal extension portion in the pants-type absorbent article is effective for suppressing leakage from the dorsal side.

PRIOR ART DOCUMENTS

PATENT DOCUMENTS

[0005]

PATENT DOCUMENT 1

PATENT DOCUMENT 2

SUMMARY OF THE INVENTION

PROBLEMS TO BE SOLVED BY THE INVENTION

[0006] There is a need for pant-type absorbent garments that have a dorsal extension that is both comfortable around the abdomen and less likely to slip down.

[0007] The present invention relates to a pant-type absorbent article that is comfortable around the abdomen and has a dorsal extension that prevents it from slipping down. [Means for solving the problem]

[0008] One embodiment of the present invention comprises an absorbent pant-type article and an outer casing. The above-mentioned pant-type absorbent article has a longitudinal direction extending from the wearer's abdominal side through the crotch area to the back, and a transverse direction perpendicular to the longitudinal direction. The outer casing described above is positioned on the non-skin-facing side of the absorbent body and has a waist opening and a pair of leg openings. The above-mentioned outer body has a ventral portion, a dorsal portion, and a crotch portion. The ventral portion described above is positioned on the wearer's ventral side and has a ventral waist end that constitutes the waist opening described above. The aforementioned back portion is positioned on the wearer's back and has a back waist end that constitutes the waist opening. The above-mentioned crotch area is positioned in the wearer's crotch area, located between the above-mentioned ventral and dorsal parts, and is connected to the above-mentioned ventral and dorsal parts, forming the leg opening. The dorsal waist end is located further from the pair of leg openings in the longitudinal direction than the ventral waist end. The rear portion of the exterior body has a rear extension and a rear main body. The dorsal extension extends in the longitudinal direction from the ventral waist end to the dorsal waist end. The dorsal main body portion described above is the portion obtained by removing the dorsal extension portion described above from the dorsal portion. The exterior body has an elastic leg body that forms leg gathers and is positioned circumferentially within the leg opening. The above-mentioned leg elastic body comprises one or more dorsal leg elastic bodies and one or more ventral leg elastic bodies. The elastic body for the back leg described above is positioned across the back and crotch area. The elastic body for the ventral leg is positioned across the ventral portion and the crotch area. In the extended and unfolded state, the elastic body for the dorsal leg and the elastic body for the ventral leg have portions that are inclined with respect to the longitudinal direction. In the extended and unfolded state, the shortest distance in the longitudinal direction from the dorsal waist end to the elastic body for the dorsal leg is longer than the shortest distance in the longitudinal direction from the ventral waist end to the elastic body for the ventral leg. The ventral portion includes the ventral waist end and has a ventral waist region that extends across the entire lateral width of the ventral portion, with the same longitudinal length as the dorsal extension. The dorsal extension mentioned above has higher rigidity than the ventral waist region mentioned above. [Effects of the Invention]

[0009] According to the present invention, the absorbent pant-type article does not cause discomfort to the abdomen and is less likely to slip down. [Brief explanation of the drawing]

[0010] [Figure 1] This is a plan view of a pant-type absorbent article laid flat at its natural length, according to each embodiment of the present invention. [Figure 2] (A) is a schematic side view of the above-mentioned pant-type absorbent article, and (B) is an enlarged view of the area enclosed by circle IIB in (A). [Figure 3] This is a schematic plan view showing the skin-facing side of a pant-type absorbent article according to the first embodiment, and is a diagram showing the pant-type absorbent article unfolded and each elastic body stretched out to form a flat surface. [Figure 4] This is a schematic plan view showing the skin-facing side of a pant-type absorbent article according to the first embodiment, and is a diagram showing the pant-type absorbent article unfolded and each elastic body stretched out to form a flat surface. [Figure 5](A) is a schematic cross-sectional view of the back side part and the belly side part of the pants-type absorbent article according to the first embodiment, and (B) is a schematic cross-sectional view of the back side part and the belly side part of the pants-type absorbent article of a modified example. [Figure 6] This is a partial view showing a state where a wearer wearing the pants-type absorbent article according to each embodiment of the present invention is lying on their back. [Figure 7] This is a schematic plan view showing the side seal and the side reinforcing portion of the pants-type absorbent article. [Figure 8] This is a schematic cross-sectional view of the back side part and the belly side part of the pants-type absorbent article according to the second embodiment of the present invention. [Figure 9] This is a schematic cross-sectional view of the back side part and the belly side part of the pants-type absorbent article according to the third embodiment of the present invention. [Mode for Carrying Out the Invention]

[0011] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the same reference numerals are assigned to the configurations that have already been presented, and descriptions thereof may be omitted.

[0012] 《First Embodiment》 <Overall Configuration of Pants-type Absorbent Article> In FIG. 1, FIG. 2(A), FIG. 3 and FIG. 4, a pants-type disposable diaper 1 is shown as the pants-type absorbent article of the first embodiment according to one embodiment of the present invention. The pants-type disposable diaper 1 is hereinafter referred to as the diaper 1. FIG. 1 is a plan view of the diaper 1 in a natural length state laid flat. The "natural length state" means a state where no external force such as stretching is applied to the diaper 1. The term "when laid flat" means a state where the unused diaper 1 is placed on a flat placement surface such as a floor, a stand, a shelf, or a desk. FIG. 2(A) schematically shows the diaper 1 when worn, and the wearer's torso 13 and legs 14 are also illustrated. Both FIG. 3 and FIG. 4 are plan views of the skin side surface of the diaper in an unfolded and stretched state, and FIG. 3 and FIG. 4 are prepared to make the drawings easier to see when describing each configuration of the diaper.

[0013] As shown in Figure 1, the diaper 1 has a waist opening 1W and a pair of leg openings IL, and is worn around the wearer's waist and crotch. The waist opening 1W has a waist opening end Wa. The diaper 1 has a vertical direction X and a horizontal direction Y. The vertical direction X extends from the wearer's ventral side through the crotch to the dorsal side. The horizontal direction Y is perpendicular to the vertical direction X and corresponds to the wearer's left-right direction. Furthermore, as shown in Figures 3 and 4, the direction perpendicular to the vertical direction X and the horizontal direction Y of the diaper 1 is defined as the thickness direction Z.

[0014] In this specification, "waist side" and "upper side" mean the side in the vertical direction X that is closer to the waist opening end Wa of the waist opening 1W and away from the leg opening 1L. "Leg side" and "lower side" mean the side in the vertical direction X that is away from the waist opening end Wa and closer to the leg opening 1L. In this specification, "inside of transverse direction Y" means the side of the diaper (pant-type absorbent article) that is closer to the vertical center line CL that divides the diaper (pant-type absorbent article) in the transverse direction Y, and "outside of transverse direction Y" means the side that is further away from the vertical center line CL. In this specification, with respect to the thickness direction Z, the side of the diaper closer to the wearer's skin when worn is referred to as the "skin side," and the side closer to the clothing is referred to as the "non-skin side." Furthermore, "skin-facing surface" means the surface of the diaper or its components that faces the wearer's skin, i.e., the surface that is relatively close to the wearer's skin. "Non-skin-facing surface" means the surface of the diaper or its components that faces the opposite side (clothing side) from the skin-facing surface, i.e., the surface that is relatively far from the wearer's skin.

[0015] When an infant or toddler puts on diaper 1, they first put their legs through the pair of leg openings 1L, pull up diaper 1, and position diaper 1 around the wearer's waist and groin. In this specification, this series of actions is referred to as the "wearing action." The wearing action may also be performed by a caregiver rather than the wearer of diaper 1. For this reason, in this specification, the main performer of the wearing action is referred to as the "caregiver." In this specification, the state in which diaper 1 is positioned in the normally expected and appropriate wearing position for the wearer is referred to as "wearing."

[0016] As shown in Figures 1, 2(A), 3, and 4, the diaper 1 comprises an absorbent body 4 and an outer casing 5 positioned on the non-skin-facing side of the absorbent body 4. The diaper 1 also comprises multiple elastic waistbands 70, leg elastic bands 11, and three-dimensional gather elastic bands 25. Figures 3 and 4 show the diaper 1 unfolded and with each elastic body stretched to achieve the design dimensions, completely eliminating the influence of the elastic bodies. This unfolded and stretched state is also referred to as the "unfolded and stretched state" of the diaper 1. Unfolding the diaper 1 means separating the ventral portion 3 and the dorsal portion 6 of the side seal 8, which will be described later.

[0017] As shown in Figure 5(A), in diaper 1, the outer casing 5 is folded back towards the skin-facing side at the ventral waist end 101 and the dorsal waist end 102. This folded portion of the outer casing 5 is called the "folded portion." The dorsal extension 60 (dorsal waist region) and the ventral waist region 35 each have a dorsal folded portion 6a and a ventral folded portion 3a, where the other end of the outer casing 5 in the longitudinal direction X is folded back towards the skin-facing side. The dorsal folded portion 6a and the ventral folded portion 3a are positioned to cover the dorsal end 106 and the ventral end 107 of the absorbent body.

[0018] Furthermore, the diaper 1 is further equipped with a disposal tape (not shown) having a handle portion, which is positioned on the dorsal side 6 so as to overlap with the absorbent body 4 in a plan view. Also, as will be described in detail later, as shown in Figure 1, the dorsal side 6 of the outer casing 5 of the diaper 1 has a dorsal extension 60 that protrudes vertically upward from the ventral side 3.

[0019] <Exterior structure> The outer casing 5 includes a plurality of thermoplastic sheets 50. The outer casing 5 is configured, for example, as a laminate of a plurality of thermoplastic sheets 50. The thermoplastic sheet 50 is a sheet material mainly composed of thermoplastic resin. The thermoplastic sheet 50 preferably contains 90% by mass or more of thermoplastic resin, and more preferably consists of 100% by mass of thermoplastic resin. In addition, multiple thermoplastic sheets 50 may also contain cellulosic fibers in addition to thermoplastic fibers. Examples of thermoplastic resins include polyolefins such as polyethylene and polypropylene; polyesters such as polyethylene terephthalate; polyamides such as nylon 6 and nylon 66; polyacrylic acid, polyalkyl methacrylate, polyvinyl chloride, and polyvinylidene chloride. These can be used individually or in combination of two or more. The thermoplastic fibers may be short or long fibers. As thermoplastic fibers, composite fibers such as core-sheath type or side-by-side type, split fibers, irregularly shaped cross-section fibers, and heat-shrinkable fibers can also be used. Examples of cellulose fibers include natural cellulose fibers such as cotton and pulp, and regenerated cellulose fibers such as rayon and cupro. These can be used individually or in combination of two or more types.

[0020] The outer casing 5 preferably includes, as a plurality of thermoplastic sheets 50, an outer layer sheet 51 and an inner layer sheet 52, as shown in the diaper 1 of this embodiment in Figure 5(A). The outer layer sheet 51 is positioned on the non-skin side of the inner layer sheet 52 and constitutes the non-skin facing surface of the outer casing 5. Preferably, a plurality of elastic waistbands 70 are arranged between the inner layer sheet 52 and the outer layer sheet 51.

[0021] As shown in Figures 1, 2(A), 3, and 4, the outer casing 5 has a ventral portion 3, a crotch portion 9, and a dorsal portion 6. The ventral portion 3, the crotch portion 9, and the dorsal portion 6 are arranged along the longitudinal direction X. The dorsal portion 6 has a dorsal extension portion 60 and a dorsal main body portion 61. The outer edge of the outer casing 5 is preferably configured to be symmetrical (left-right symmetrical) with respect to the longitudinal center line CL.

[0022] Furthermore, the outer casing 5 has a pair of side seals 8, each formed by joining the lateral edge 54 of the ventral portion 3 in the lateral direction Y and the lateral edge 55 of the dorsal main body portion 61 in the lateral direction Y. In other words, the right side seal 8 has a configuration in which the right lateral edge 54 of the ventral portion 3 and the right lateral edge 55 of the dorsal main body portion 61 are joined together by overlapping them in the thickness direction Z. The left side seal 8 has a configuration in which the left lateral edge 54 of the ventral portion 3 and the left lateral edge 55 of the dorsal portion 6 are joined together by overlapping them in the thickness direction Z. The pair of side seals 8, each extending in the vertical direction X, cause the ventral portion 3 and the dorsal main body portion 61 to form a cylindrical shape that conforms to the wearer's waist, forming the waist opening 1W and leg openings 1L of the diaper 1. As shown in Figure 3, the lateral edge 54 of the ventral portion 3 is a portion having a predetermined width, including the lateral edge 540 which is the lateral edge (lateral edge located on the left and right sides) of the ventral portion 3 in the lateral direction Y. The side edge portion 55 of the dorsal main body portion 61 is a portion having a predetermined width, including the side edge 550 which is the side edge (side edge located on the left and right) of the dorsal main body portion 61 in the lateral direction Y. The width of each of the side edges 54 and 55 is preferably 1.5 mm or more and 10 mm or less, more preferably 2 mm or more and 8 mm or less.

[0023] The ventral portion 3 of the outer garment 5 has a ventral waist end 101 that forms the waist opening end Wa of the waist opening 1W. The dorsal portion 6 of the outer garment 5 has a dorsal waist end 102 that forms the waist opening end Wa of the waist opening 1W. The dorsal waist end 102 is located further from the pair of leg openings 1L in the longitudinal direction X than the ventral waist end 101. The dorsal waist end 102 is the end (dorsal extension end) of the dorsal extension portion 60. The crotch area 9 is located between the ventral portion 3 and the dorsal portion 6, is connected to the ventral portion 3 and the dorsal portion 6, and forms the leg opening 1L.

[0024] As shown in Figures 3 and 4, on the dorsal portion 6, one or more elastic bodies 70R for the dorsal waist, which are stretchable in the lateral direction Y and extended in the lateral direction Y, are intermittently arranged in the longitudinal direction X. On the ventral portion 3, one or more elastic bodies 70F for the ventral waist, which are stretchable in the lateral direction Y and extended in the lateral direction Y, are intermittently arranged in the longitudinal direction X. When it is not necessary to distinguish between the ventral waist elastic body 70F and the dorsal waist elastic body 70R, they are referred to as waist elastic body 70. The waist elastic body 70 is fixed to the thermoplastic sheet 50 that constitutes the outer casing 5 in an extended state, and when the extended state is released and the elastic body contracts, a waist gather G1 is formed on the outer casing 5.

[0025] As shown in Figures 1, 3, and 4, the outer casing 5 has leg elastic bodies 11 arranged along the circumferential direction of each of the pair of leg openings 1L. The leg elastic bodies 11 are fixed to the thermoplastic sheet 50 that constitutes the outer casing 5 when extended, and when the extended state is released and the elastic bodies contract, leg gathers G2 are formed on the outer casing 5.

[0026] The elastic waistband 70 that forms the waist gather G1, the elastic legband 11 that forms the leg gather G2, and the elastic three-dimensional gather 25 that forms the three-dimensional gather G3 can preferably be made of thread-like material (such as elastic thread) or string-like material (such as flat elastic) with a rectangular, square, circular, or polygonal cross-section, or of a multifilament type thread-like material. The materials for the elastic waistband 70, the elastic legband 11, and the elastic three-dimensional gather 25 can be any material conventionally used in absorbent articles such as disposable diapers, and are not particularly limited. Examples include synthetic rubber such as styrene-butadiene, butadiene, isoprene, and neoprene, natural rubber, EVA, stretchable polyolefin, and polyurethane.

[0027] The elastic waistband 70, the elastic leg band 11, and the elastic three-dimensional gather band 25 are each stretchable along their longitudinal direction. Each elastic band is fixed to the thermoplastic sheet 50, for example, by adhesive. Details of each elastic band will be described later.

[0028] [Structure of the ventral region] As shown in Figures 3 and 4, the ventral portion 3 has a ventral waist region 35 including the ventral waist end 101 and a ventral lower portion 34. The ventral waist region 35 has the same length in the longitudinal direction X as the dorsal extension 60 and has a band shape that extends across the entire width in the transverse direction Y of the ventral portion 3. The ventral lower portion 34 is the region furthest from the ventral waist end 101 (the region located furthest away) when the ventral portion 3 is divided into three equal parts in the longitudinal direction X when it is unfolded and extended, and has a rectangular shape.

[0029] [Composition of the dorsal side] The rear portion 6 of the outer casing 5 has a rear extension portion 60 and a rear main body portion 61.

[0030] The dorsal extension 60 extends in the longitudinal direction X from the ventral waist end 101 to the dorsal waist end 102. The dorsal extension 60 includes the dorsal waist end 102 and corresponds to the "dorsal waist region". In the unfolded and extended state shown in Figures 3 and 4, the dorsal extension 60 has a rectangular shape.

[0031] As shown in Figures 1, 2(A) and (B), and 3, the dorsal extension portion 60 has a pair of dorsal extension side edges 104 that are opposite each other in the lateral direction Y and extend in the vertical direction X, and a pair of side reinforcing portions 105 provided on each of the pair of dorsal extension side edges 104. Each of the pair of dorsal extension side edges 104 extends in the vertical direction X. The dorsal extension side edges 104 are portions having a predetermined width, including the dorsal extension side edges 1040 which are the side edges (side edges located on the left and right) of the dorsal extension portion 60 in the lateral direction Y. The width of the dorsal extension side edges 104 is preferably 1.5 mm or more and 10 mm or less, more preferably 2 mm or more and 8 mm or less. Details of the side reinforcing portions 105 and the side seal 8 will be described later.

[0032] The dorsal main body portion 61 is the portion obtained by removing the dorsal extension portion 60 from the dorsal portion 6. In other words, the dorsal main body portion 61 is the portion that is in the same position as the ventral portion 3 in the longitudinal direction X, while the dorsal extension portion 60 is the portion that does not face the ventral portion 3 and protrudes upward in the longitudinal direction X. In this specification, "the ventral portion and the dorsal portion being in the same position in the longitudinal direction X" means that, when viewing the vicinity of the side seal 8 of the stretched diaper 1, the ventral portion and the dorsal portion coincide in position and length in the longitudinal direction X and are adjacent to each other. As shown in Figures 3 and 4, the boundary between the dorsal extension portion 60 and the dorsal main body portion 61 (shown by a hypothetical dashed line) is denoted by reference numeral 103.

[0033] As shown in Figure 1, in the diaper 1 in its natural length state, the dorsal waist end 102 is generally in an almost straight line, roughly parallel to the transverse direction Y. The length of the dorsal extension 60 in the vertical direction X (i.e., the length from the boundary 103 to the dorsal waist end 102) is preferably, for example, 10 mm to 40 mm, from the viewpoint of effectively preventing the dorsal extension 60 from rolling up and effectively preventing leakage of excrement from the dorsal side. The length of the dorsal extension 60 in the vertical direction X refers to the minimum length. As shown in Figures 3 and 4, in the diaper 1 of this embodiment, in the unfolded and extended state, the length of the dorsal extension 60 in the vertical direction X (the length from the dorsal waist end 102 to the boundary 103 in the vertical direction X) is equal across the entire width in the transverse direction Y. However, if it is not equal across the entire width in the transverse direction Y, the length of the part of the dorsal extension 60 where the length in the vertical direction X is smallest (minimum length) is defined as the "length of the dorsal extension 60 in the vertical direction X". The longer the dorsal extension 60, the better it can prevent loose stools and other excrement from leaking out from the dorsal extension 60. However, the dorsal extension 60 is more prone to curling up, so it is preferable that the length of the dorsal extension 60 be 40 mm or less. On the other hand, if the dorsal extension 60 is too short, it is more likely to fold inward when pulling up the diaper 1, so it is preferable that the length of the dorsal extension 60 be 10 mm or more. Furthermore, from the viewpoint of achieving both material cost reduction and effective suppression of leakage from the dorsal side, it is preferable that, as in the diaper 1 of this embodiment, the length in the vertical direction X of the dorsal extension portion 60 is equal across the entire width in the horizontal direction Y when extended and unfolded.

[0034] Furthermore, as shown in Figures 3 and 4, the dorsal main body portion 61 has a dorsal lower portion 64. The dorsal lower portion 64 is the region furthest from the dorsal waist end portion 102 (the region located furthest away) when the dorsal main body portion 61 is divided into three equal parts in the longitudinal direction X. The dorsal lower portion 64 is in the same position as the ventral lower portion 34 in the longitudinal direction X.

[0035] In diaper 1, the ventral portion 3 and the dorsal main body portion 61 are in the same position in the longitudinal direction X and are joined by a side seal 8 to form a ring. On the other hand, the dorsal extension portion 60 is not ring-shaped because there is no portion of the ventral portion in the same position in the longitudinal direction X, and is provided with a pair of dorsal extension side edges 104 that serve as free ends on both sides in the transverse direction Y.

[0036] [Inseam construction] As shown in Figures 1 to 4, the crotch area 9 is located between the ventral area 3 and the dorsal area 6, and is connected to both the ventral area 3 and the dorsal area 6. In the extended and unfolded state, the crotch area 9 has a shape that is constricted inward in the lateral direction Y. This creates a leg opening 1L (see Figure 1, etc.) that conforms to the wearer's leg opening.

[0037] <Composition of the absorbent body> The absorbent body 4 is fixed to the skin-facing side of the outer casing 5. The absorbent body 4 has at least an absorbent 40 and may further have a surface sheet 2, a back sheet 7, etc. For example, the absorbent body 4 has a configuration in which the back sheet 7, the absorbent 40 and the surface sheet 2 are laminated in the thickness direction Z (see Figure 5(A)). The absorbent 40 includes a liquid-retaining absorbent core and may further include a core wrap sheet that covers the absorbent core. The absorbent body 4 has a dorsal end 106 located on the dorsal side 6, which is the end in the longitudinal direction X, and a ventral end 107 located on the ventral side 3, which is the end in the longitudinal direction X. The materials used in each component of the absorbent body 4 (back sheet 7, absorbent material 40, front sheet 2, etc.) can be any material used in the relevant art without any particular limitations.

[0038] As shown in Figure 5(A), the absorbent body 4 comprises a liquid-permeable surface sheet 2 that forms the skin side, a liquid-impermeable (including water-repellent) back sheet 7 that forms the non-skin side, and a liquid-retaining absorbent 40 positioned between the surface sheet 2 and the back sheet 7. The absorbent 40 and the surface sheet 2 are bonded together with an adhesive (not shown). The absorbent 40 and the back sheet 7 are bonded together with an adhesive (not shown).

[0039] In diaper 1, the total length of the absorbent body 4 in the vertical direction X is slightly longer than the total length of the absorbent material 40 in the vertical direction X. The ends 106 and 107 of the absorbent body 4 in the vertical direction X are located closer to the waist than the ends of the absorbent material 40 in the vertical direction X.

[0040] The absorbent body 40 has an absorbent core (not shown) and a core wrap sheet (not shown). A core wrap sheet is a liquid-permeable sheet that covers at least the skin-facing side of an absorbent core. Typically, the core wrap sheet is configured to cover the entire surface of the absorbent core, including both the skin-facing and non-skin-facing sides. Examples of core wrap sheets include tissue paper made of hydrophilic fibers and liquid-permeable nonwoven fabrics. The absorbent core contains a superabsorbent polymer and pulp fibers. Specifically, the absorbent core is composed of, for example, an aggregate of hydrophilic fibers such as cellulose including pulp fibers, an aggregate of the hydrophilic fibers and a superabsorbent polymer, or a laminated structure in which a superabsorbent polymer is supported between two absorbent sheets.

[0041] As shown in Figures 3 and 5(A), the dorsal end 106 of the absorbent body is located closer to the leg opening 1L in the longitudinal direction X than the boundary 103. In other words, the absorbent body 4 is not positioned on the dorsal extension 60. This prevents the soft stool absorbed by the absorbent body 4 from moving to the dorsal extension 60, and prevents the soft stool from leaking from the dorsal waist end 102 of the outer casing 5.

[0042] <Configuration of side seal and side reinforcement section> As shown in Figure 7, the side seal 8 typically includes a plurality of sealing portions S. The sealing portions S are the portions where the thermoplastic sheets 50 of both the ventral portion 3 and the dorsal main body portion 61 are fused and joined. The sealing portions are joined, for example, by pressurizing means and / or heating means, specifically by heat sealing or ultrasonic sealing. The plurality of sealing portions S are spaced apart in the longitudinal direction X and each extends in the transverse direction Y.

[0043] As shown in Figure 7, the pair of side reinforcing portions 105 are provided on the pair of dorsal extension side edges 104 of the dorsal extension portion 60 and are continuous with the side seal 8. The side reinforcing portions 105 include multiple sealing portions S, similar to the side seal 8. Since the side reinforcing portions 105 are continuous with the side seal 8 and have a configuration that includes multiple sealing portions S, similar to the side seal 8, the diaper 1 can be manufactured easily without increasing the manufacturing process or materials.

[0044] In the example shown in Figure 7, the sealing portion S has a rectangular shape with the horizontal direction Y as its longitudinal direction. Multiple sealing portions S are intermittently arranged along the vertical direction X.

[0045] As shown in Figure 7, in the side seal 8 (side reinforcement portion 105), the rectangular area surrounding the entire contour of the multiple seal portions S is referred to as the seal region B. The seal region B is a region with higher rigidity compared to the region without seal portions S. Thus, the side seal 8 (side reinforcement portion 105) includes a rectangular, relatively rigid seal region B. The rigidity of the side reinforcement portion 105 is increased by the inclusion of the seal region B, and the dorsal extended side edge portion 104 is reinforced.

[0046] As shown in Figure 7, the width of the rectangular side seal 8, which extends in a band shape in the vertical direction X (corresponding to the width of the side edges 54 and 55), is defined as extending from the side edge on the inside of the seal region B in the horizontal direction Y to the side edge 540 of the ventral portion 3 and the side edge 550 of the dorsal main body portion 61. The side edge located on the lateral Y side of the side seal 8 is referred to as the inner side seal side edge 8d. This inner side seal side edge 8d coincides with the side edge located on the lateral Y side of the seal region B. The side edge located on the lateral Y-outward side of the side seal 8 is referred to as the outer side seal side edge 8c. This outer side seal side edge 8c coincides with side edges 540 and 550. As shown in Figure 7, each sealing portion S of the side seal 8 does not reach the side edges 540 and 550 in the lateral direction Y, and the side edges located on the lateral side Y of the sealing region B are located laterally inward from the side edges 540 and 550. In other words, the range of each of the left and right side seals 8 is the area from the side edge (inner side seal side edge 8d) that extends in the vertical direction X and is located inside the lateral direction Y of the rectangular seal area B, to the side edges 540 and 550.

[0047] As shown in Figure 7, the width range of the rectangular side reinforcement portion 105, which extends in a band shape in the vertical direction, is defined as extending from the side edge on the inside of the seal region B in the lateral direction Y to the dorsal extension side edge 1040 of the dorsal extension portion 60. The side edge located on the inner side in the lateral direction Y of the side reinforcement portion 105 is referred to as the inner side reinforcement portion side edge 105d. This inner side reinforcement portion side edge 105d coincides with the side edge located on the inner side in the lateral direction Y of the seal region B. The side edge located on the lateral Y-outward side of the side reinforcement portion 105 is referred to as the outer side reinforcement portion side edge 105c. This outer side reinforcement portion side edge 105c coincides with the dorsal extension side edge 1040. As shown in Figure 7, each sealing portion S of the side reinforcement portion 105 does not reach the dorsal extending side edge 1040 in the lateral direction Y, and the side edges located on the outside in the lateral direction Y of the sealing region B are located inward in the lateral direction Y than the dorsal extending side edge 1040. In other words, in the dorsal extension portion 60, the range of each of the left and right pair of side reinforcing portions 105 is the region from the inner side reinforcing portion side edge 105d, which is the side edge extending in the vertical direction X located inside the lateral direction Y of the rectangular seal region B, to the dorsal extension side edge 1040.

[0048] The side reinforcement portion 105 is a highly rigid area due to the presence of multiple sealing portions S. By providing the side reinforcement portion 105 on the dorsal extension side edge portion 104, the rigidity of the pair of dorsal extension side edge portions 104 is increased, making the dorsal extension portion 60 less likely to curl up.

[0049] As shown in Figures 2(A) and (B), the pair of side seals 8 each have an upper end portion 8a and a lower end portion 8b, which constitute both ends in the vertical direction X. Because the side reinforcement portion 105 and the side seal 8 are continuous, the dorsal extension portion 60 is less likely to bend at the boundary portion 110 between the side reinforcement portion 105 and the side seal 8, and consequently, bending of the dorsal extension portion 60 at the boundary portion 103 is suppressed. In the continuous side seal 8 and side reinforcement portion 105, the upper end portion 8a of the side seal is located at the boundary portion 110 between the side seal 8 and the side reinforcement portion 105. The upper end portion 8a of the side seal is the waist end of the side seal 8. The lower end portion 8b of the side seal is the leg end of the side seal 8.

[0050] As shown in Figures 2(A) and (B), the pair of side reinforcement portions 105 each have an upper end portion 105a and a lower end portion 105b, which constitute both ends in the vertical direction X. The upper end portion 105a of the side reinforcement portion is located at the back waist end portion 102. The lower end portion 105b of the side reinforcement portion corresponds to the boundary portion 110 between the side seal 8 and the side reinforcement portion 105, and is located at the same position as the upper end portion 8a of the side seal. In Figure 2(B), the boundary portion 110 is virtually shown with a thick dashed line.

[0051] As shown in Figures 1 to 3, a first point P1 is set on the upper end 105a of the side reinforcement. Specifically, the first point P1 is the innermost point in the lateral direction Y of the upper end 105a of the side reinforcement. A second point P2 is set on the lower end 105b of the side reinforcement. Specifically, the second point P2 is the innermost point in the lateral direction Y of the lower end 105b of the side reinforcement. In the unfolded and extended state, the first point P1 and the second point P2 are located on the inner side edge 105d of the side reinforcement, which is on the lateral side Y side of the band-shaped side reinforcement 105. The first point P1 is located on the dorsal waist end 102. The second point P2 is in the same position as the innermost point in the lateral direction Y of the upper end 8a of the side seal. In other words, the second point P2 is located on the inner side edge 8d of the side seal, which is on the lateral side Y side of the band-shaped side seal 8. The second point P2 is located on the ventral waist end 101.

[0052] In Figure 1, the approximate curve that roughly represents the overall shape of the ventral waist end 101, which is roughly aligned with the ventral waist end 101, is called the "first virtual line L1". The approximate curve that roughly represents the overall shape of the dorsal waist end 102, which is roughly aligned with the dorsal waist end 102, is called the "second virtual line L2". The straight line passing through the pair of second points P2 on the left and right is called the "third virtual line L3". The shapes of the ventral waist end 101 and the dorsal waist end 102 have fine irregularities due to the waist gathers G1 (folds) formed by the elastic waist material 70, so they are represented here by approximate curves.

[0053] As shown in Figure 3, in the unfolded and extended state, the shortest distance from the ventral waist end 101 to the elastic body 11F for the ventral leg in the longitudinal direction X is defined as "distance a". More specifically, as shown in Figure 3, "distance a" is the distance between a second point P2 and a fourth point P4 located on the inner side seal edge 8d of the side seal 8 in the unfolded and extended state. As shown in Figure 3, the second point P2 is a point on the ventral waist end 101 where the ventral waist end 101 and the inner side seal edge 8d of the side seal 8 come into contact. The fourth point P4 is where the inner side seal edge 8d of the side seal 8 intersects with the ventral leg elastic body 11F (ventral leg elastic body 11Fa in the example shown in Figure 3) that is closest to the ventral waist end 101 among the one or more ventral leg elastic bodies 11F. Furthermore, if the ventral leg elastic body 11Fa closest to the ventral waist end 101 does not reach the side seal 8, a virtual line parallel to the transverse direction Y is drawn passing through the extending outer end (lateral outer end) of the ventral leg elastic body 11F, and the point where this virtual line intersects with the inner side seal edge 8d of the side seal 8 is designated as the fourth point P4.

[0054] As shown in Figure 3, in the unfolded and extended state, the shortest distance from the dorsal waist end 102 to the dorsal leg elastic body 11R in the longitudinal direction X is defined as "distance b". More specifically, as shown in Figure 3, "distance b" is the distance between a first point P1 located on the inner side edge 105d of the side reinforcement portion 105 in the unfolded and extended state, and a third point P3 located on the inner side edge 8d of the side seal 8 which is continuous with the side reinforcement portion 105. As shown in Figure 3, the first point P1 is a point on the dorsal waist end 102, where the dorsal waist end 102 and the inner side edge 105d of the side reinforcement portion 105 come into contact. The third point P3 is where the inner side edge 8d of the side seal 8 intersects with the dorsal leg elastic body 11R (in the example shown in Figure 3, dorsal leg elastic body 11Ra) that is closest to the dorsal waist end 102 among the one or more dorsal leg elastic bodies 11R. Furthermore, if the elastic body 11R for the back leg closest to the back waist end 102 does not reach the side seal 8, a virtual line parallel to the transverse direction Y is drawn passing through the extending outer end (lateral outer end) of the elastic body 11Ra for the back leg, and the point where this virtual line intersects with the inner side seal edge 8d of the side seal 8 is defined as the third point P3. Also, if the side reinforcement portion 105 is not provided on the back extension portion 60, in the unfolded and extended state, the inner side seal edge 8d of the side seal 8 is virtually extended parallel to the longitudinal direction X to the back waist end 102, and the point where this extension line abuts the back waist end 102 is defined as the first point P1.

[0055] Furthermore, in diaper 1, the side reinforcement portion 105 and the side seal 8 are in areas where the elastic force of the waist elastic material is less affected, and the distance a in the natural length state and the distance a in the unfolded and extended state are approximately the same, and the distance b in the natural length state and the distance b in the unfolded and extended state are approximately the same. Here, "approximately the same" means that the difference between the dimensions in the natural length state and the dimensions in the unfolded and extended state is within 2 mm.

[0056] <Composition of three-dimensional gathers> As shown in Figures 3 and 4, each side of the absorbent body 4 along the longitudinal direction X is provided with a leak-proof cuff 24 having an elastic body 25 for three-dimensional gathering that is stretched in the longitudinal direction X. The leak-proof cuff 24 is made of a material that is impermeable to liquid or water-repellent and breathable. The elastic body 25 for three-dimensional gathering is provided near the free end 24a of the leak-proof cuff 24. When the diaper 1 is worn, the contraction of the elastic body 25 for three-dimensional gathering causes the free end 24a side of the leak-proof cuff to stand up, forming a three-dimensional gather G3, which prevents the outflow of bodily fluids in the lateral direction Y. The three-dimensional gather G3 extends in the longitudinal direction X along both sides of the absorbent body 4 in the lateral direction Y. In addition, when the diaper 1 is pulled up, the contraction response of the elastic body 25 for three-dimensional gathering makes it easier to pull the absorbent body 4 up to the vicinity of the wearer's crotch.

[0057] As shown in Figure 4, the three-dimensional gather G3 has ventral fixing portion 151 and dorsal fixing portion 152 (shown as dots in Figure 4) at both ends of the longitudinal direction X, to which the leak-proof cuff 24 is fixed to the absorbent body 4 (more specifically, the surface sheet 2). When the diaper 1 is viewed in the thickness direction Z, the ventral fixing portion 151 is located on the ventral portion 3, and the dorsal fixing portion 152 is located on the dorsal portion 6. The elastic body 25 for the three-dimensional gather may be present in the ventral fixing portion 151 and the dorsal fixing portion 152, or it may not be present as shown in Figure 4.

[0058] As shown in Figure 4, the three-dimensional gather G3 has a ventral three-dimensional gather contraction start position Q1 and a dorsal three-dimensional gather contraction start position Q2 opposite each other in the longitudinal direction X. When the diaper 1 is viewed in the thickness direction Z, the ventral three-dimensional gather contraction start position Q1 is located on the ventral part 3, and the dorsal three-dimensional gather contraction start position Q2 is located on the dorsal part 6. The ventral three-dimensional gather contraction start position Q1 and the dorsal three-dimensional gather contraction start position Q2 are the positions where contraction by the elastic material 25 for the three-dimensional gather in the three-dimensional gather G3 begins, respectively.

[0059] <Waist support elastic material> As shown in Figure 5(A), the multiple waist elastic bodies 70 are arranged between the multiple thermoplastic sheets 50 of the outer casing 5. In the example shown in Figure 5(A), the multiple waist elastic bodies 70 are arranged extending in the lateral direction Y between the outer layer sheet 51 and the inner layer sheet 52. Multiple waist elastic members 70 provide elasticity to the waist of the diaper 1, making it easier to put on and maintaining a good fit when worn. The multiple waist elastic members 70 include a back waist elastic member 70R located on the back side 6 and a front waist elastic member 70F located on the front side 3. Furthermore, "the waist elastic body 70 extends in the lateral direction Y" means that the waist elastic body 70 extends in the lateral direction Y when unfolded and extended. However, the above expression is not limited to the waist elastic body 70 being parallel to the lateral direction Y when unfolded and extended, but also includes the configuration in which the entire body extends in the lateral direction Y. In this embodiment, an example is given in which all of the waist elastic bodies 70 are parallel to the lateral direction Y.

[0060] From the viewpoint of ensuring elasticity of the entire waist circumference, the lateral Y-outer ends of the waist elastic body 70, which are positioned on the ventral portion 3 and the dorsal portion 6 respectively, are preferably located within or near the side seal 8 and the side reinforcement portion 105. Specifically, it is preferable that the distance in the lateral Y direction from the side seal 8 and the side reinforcement portion 105 of the end is 10 mm or less, and it is more preferable that the distance is 0 mm and the end is located within the side seal 8 and the side reinforcement portion 105.

[0061] As shown in Figures 3 and 4, the ventral portion 3 has multiple (13 in this embodiment) ventral waist elastic bodies 70F that are expandable and contractible in the lateral direction Y and extend in the lateral direction Y, intermittently arranged in the longitudinal direction X. In the diaper 1 of this embodiment, four of the multiple ventral waist elastic bodies 70F located at the lower ventral part 34 are denoted by the reference numeral 701F. Furthermore, these four ventral waist elastic bodies 701F are, if necessary, denoted by reference numerals 701Fa, 701Fb, 701Fc, and 701Fd in the longitudinal direction X from the ventral waist end 101 towards the leg opening 1L.

[0062] As shown in Figures 3 and 4, the back portion 6 has multiple (13 in this embodiment) elastic waistbands 70R for the back, which are stretchable in the lateral direction Y and extended in the lateral direction Y, intermittently arranged in the longitudinal direction X. In the diaper 1 of this embodiment, four of the multiple elastic back waist members 70R located at the lower back 64 are denoted with reference numeral 701R. Furthermore, for these four elastic back waist members 701R, reference numerals 701Ra, 701Rb, 701Rc, and 701Rd are denoted sequentially in the vertical direction X from the back waist end 102 towards the leg opening 1L, as needed.

[0063] As shown in Figure 5(A), each of the four ventral waist elastic members 701F located in the lower ventral part 34 and each of the four dorsal waist elastic members 701R located in the lower dorsal part 64 are positioned substantially in the same location in the longitudinal direction X. "Substantially in the same location" means that any design misalignment that may occur during diaper manufacturing is within 3 mm. Figure 5(A) and Figure 5(B), which will be described later, show a state in which no such manufacturing misalignment of the waist elastic members has occurred.

[0064] As shown in Figures 3 and 4, in diaper 1, multiple elastic waistbands 70 are arranged in the dorsal extension 60 and the ventral waist region 35, respectively.

[0065] In the diaper 1 of this embodiment, the four ventral waist elastic bodies 701F located in the lower ventral part 34 and the four dorsal waist elastic bodies 701R located in the lower dorsal part 64 are discontinuous elastic bodies. The discontinuous elastic body is an elastic body that has been treated so that a portion of the area overlapping with the absorbent body 4 in a plan view is cut off, thereby preventing it from having elastic stretchability. The discontinuous elastic body does not exhibit elastic stretchability in the central part of the diaper 1 in the lateral direction Y, but exhibits elastic stretchability on both sides in the lateral direction Y. In this embodiment, an elastic body that has been treated so that a portion of it does not exhibit elastic stretchability by cutting is used as the discontinuous elastic body, but it is also possible to have a configuration in which no elastic body is placed in the area where elastic stretchability is not exhibited.

[0066] In the ventral waist elastic bodies 70F located in the ventral portion 3, of the nine elastic bodies excluding the four ventral waist elastic bodies 701F, seven are continuous elastic bodies and two are discontinuous elastic bodies, with the discontinuous elastic bodies located below the continuous elastic bodies. In the dorsal waist elastic bodies 70R located in the dorsal portion 6, of the nine elastic bodies excluding the four dorsal waist elastic bodies 701R, seven are continuous elastic bodies and two are discontinuous elastic bodies, with the discontinuous elastic bodies located below the continuous elastic bodies. The continuous elastic bodies exhibit continuous elasticity across the entire width in the lateral direction Y between a pair of side reinforcement portions 105 or between a pair of side seals 8.

[0067] <Elastic material for legs> As shown in Figures 3 and 4, the leg elastic body 11 that forms the leg gathers G2 around each of the pair of leg openings 1L has a dorsal leg elastic body 11R and a ventral leg elastic body 11F. When it is not necessary to distinguish between the dorsal leg elastic body 11R and the ventral leg elastic body 11F, they are simply referred to as the leg elastic body 11.

[0068] One or more ventral leg elastic members 11F are arranged across the ventral portion 3 and the crotch area 9; in this embodiment, three are provided. These three ventral leg elastic members 11F are each labeled 11Fa, 11Fb, and 11Fc, in order from the ventral waist end 101 toward the leg opening 1L. When there is no need to distinguish between them as 11Fa, 11Fb, and 11Fc, they are simply referred to as ventral leg elastic members 11F.

[0069] One or more back leg elastic members 11R are arranged across the back portion 6 and the crotch area 9; in this embodiment, three are provided. These three back leg elastic members 11R are each labeled with the symbols 11Ra, 11Rb, and 11Rc, in order from the back waist end 102 toward the leg opening 1L. When there is no need to distinguish between them as 11Ra, 11Rb, and 11Rc, they are simply referred to as back leg elastic members 11R.

[0070] As shown in Figures 3 and 4, the ventral leg elastic body 11F, which has a longitudinal direction, has an outer end and an inner end. The ventral leg elastic body 11F has an outer end portion 111 including the outer end and its vicinity, an inner end portion 115 including the inner end and its vicinity, and an intermediate portion 113 between the outer end portion 111 and the inner end portion 115. The outer end portion 111 is located on the lateral Y side of the ventral portion 3, the inner end portion 115 is located in the lateral Y center of the crotch area 9, and the intermediate portion 113 is located near the lateral edge in the lateral Y direction of the crotch area 9. The intermediate portion 113 is a portion that is inclined with respect to the longitudinal X and lateral Y directions in the unfolded and extended state of the diaper 1. The outer end portion 111 of the ventral leg elastic body 11F is located on the ventral lower portion 34. As shown in Figures 3 and 4, in the unfolded and extended state of the diaper 1, the elastic body 11F for the ventral leg extends from its outer end to its inner end, with the outer end portion 111 extending approximately parallel to the transverse direction Y in the ventral portion 3, followed by the intermediate portion 113 extending inclined with respect to the longitudinal direction X and transverse direction Y in the crotch area 9, gradually curving to be approximately parallel to the transverse direction Y in the central longitudinal X portion of the crotch area 9, followed by the inner end portion 115 extending inward in the transverse direction Y.

[0071] As shown in Figures 3 and 4, the dorsal leg elastic body 11R, which has a longitudinal direction, has an outer end, which is one end, and an inner end, which is the other end. The dorsal leg elastic body 11R has an outer end portion 112 including the outer end and its vicinity, an inner end portion 116 including the inner end and its vicinity, and an intermediate portion 114 between the outer end portion 112 and the inner end portion 116. The outer end portion 112 is located on the lateral Y side of the dorsal portion 6, the inner end portion 116 is located in the lateral Y center of the crotch area 9, and the intermediate portion 114 is located near the lateral edge in the lateral Y direction of the crotch area 9. The intermediate portion 114 is a portion that is inclined with respect to the longitudinal X and lateral Y directions in the unfolded and extended state of the diaper 1. The outer end portion 112 of the dorsal leg elastic body 11R is located on the dorsal lower portion 64. As shown in Figures 3 and 4, in the unfolded and extended state of the diaper 1, the elastic body 11R for the dorsal leg extends from its outer end to its inner end, with the outer end portion 112 extending approximately parallel to the transverse direction Y at the dorsal portion 6, followed by the intermediate portion 114 extending inclined with respect to the longitudinal direction X and transverse direction Y at the crotch area 9, gradually curving to be approximately parallel to the transverse direction Y at the center of the longitudinal direction X of the crotch area 9, followed by the inner end portion 116 extending inward in the transverse direction Y.

[0072] As shown in Figures 3 and 4, the elastic bodies are positioned such that the inner end portion 115 of the ventral leg elastic body 11F and the inner end portion 116 of the dorsal leg elastic body 11R overlap at substantially the same position. More specifically, the inner end portion 115 of the ventral leg elastic body 11Fa and the inner end portion 116 of the dorsal leg elastic body 11Ra overlap at substantially the same position, the inner end portion 115 of the ventral leg elastic body 11Fb and the inner end portion 116 of the dorsal leg elastic body 11Rb overlap at substantially the same position, and the inner end portion 115 of the ventral leg elastic body 11Fc and the inner end portion 116 of the dorsal leg elastic body 11Rc overlap at substantially the same position.

[0073] In this specification, "substantially the same position" means that any design misalignment that may occur during diaper manufacturing is within 3 mm in the vertical X direction. In other words, "overlapping at substantially the same position" means that the inner end portion 115 and the inner end portion 116 overlap (distance between them is 0 mm), or are located in close proximity to each other (distance between them is greater than 0 mm but less than 3 mm). The same applies to the positional relationship between the outer end portion of the leg elastic body and the outer end portion of the waist elastic body, as described later.

[0074] As shown in Figures 3 and 4, in the ventral portion 3, the elastic bodies are arranged such that the outer end portion 111 of the ventral leg elastic body 11F and the outer end portion of the ventral waist elastic body 701F, which is located laterally outward in the Y direction, overlap at substantially the same position. More specifically, in the diaper 1 of this embodiment, the outer end portion 111 of the ventral leg elastic body 11Fa and the outer end portion of the ventral waist elastic body 701Fb overlap at substantially the same position, the outer end portion 111 of the ventral leg elastic body 11Fb and the outer end portion of the ventral waist elastic body 701Fc overlap at substantially the same position, and the outer end portion 111 of the ventral leg elastic body 11Fc and the outer end portion of the ventral waist elastic body 701Fd overlap at substantially the same position. In the examples shown in Figures 3 and 4, the outer end portion 111 of the ventral leg elastic body 11F and the outer end portion of the ventral waist elastic body 701F are both parallel to the lateral direction Y. However, they do not necessarily have to be parallel. For example, the outer end portion 111 of the ventral leg elastic body 11F may extend inclined with respect to the outer end portion of the ventral waist elastic body 701F, which is parallel to the lateral direction Y, and may intersect with the outer end portion of the ventral waist elastic body 701F. The same applies to the dorsal portion, which will be described later.

[0075] As shown in Figures 3 and 4, in the dorsal portion 6, the elastic bodies are arranged such that the outer end portion 112 of the dorsal leg elastic body 11R and the outer end portion of the dorsal waist elastic body 701R, which is the lateral Y-outer portion, overlap at substantially the same position. More specifically, in the diaper 1 of this embodiment, the outer end portion 112 of the dorsal leg elastic body 11Ra and the outer end portion of the dorsal waist elastic body 701Rb overlap at substantially the same position, the outer end portion 112 of the dorsal leg elastic body 11Rb and the outer end portion of the dorsal waist elastic body 701Rc overlap at substantially the same position, and the outer end portion 112 of the dorsal leg elastic body 11Rc and the outer end portion of the dorsal waist elastic body 701Rd overlap at substantially the same position.

[0076] As shown in Figures 3 and 4, in the unfolded and extended state of the diaper 1, the ventral leg elastic body 11F and the dorsal leg elastic body 11R each have intermediate portions 113 and 114 that are inclined with respect to the longitudinal X and transverse Y directions, extending from the waist opening 1W side toward the leg opening 1L side (in other words, toward the inside in the longitudinal X direction) and toward the inside in the transverse Y direction. As a result, in diaper 1, the leg elastics, consisting of a pair of left and right elastic bodies for the ventral leg 11F and a pair of elastic bodies for the dorsal leg 11R, are arranged in such a way that the distance between them in the lateral direction Y narrows at the center of the vertical direction X and widens near the front and rear ends of the vertical direction X, allowing them to be constricted inward in the lateral direction Y.

[0077] Furthermore, the leg elastic body may be configured such that the dorsal leg elastic body and the ventral leg elastic body are connected, and the leg elastic body extends continuously from the dorsal portion through the crotch area to the ventral portion. One or more such leg elastic bodies may be provided.

[0078] <Positional relationship between the waist elastic material and the leg elastic material> As shown in Figure 3, in the unfolded and extended state of the diaper 1, the shortest distance b in the longitudinal direction X from the dorsal waist end 102 to the elastic body 11R for the dorsal leg is longer than the shortest distance a in the longitudinal direction X from the ventral waist end 101 to the elastic body 11F for the ventral leg (hereinafter referred to as "configuration (1)").

[0079] <Relationship between the stiffness of the dorsal extension (dorsal waist region) and the ventral waist region> In diaper 1, the dorsal extension portion 60 has a higher rigidity than the ventral waist region 35 (hereinafter referred to as "configuration (2)"). The method for measuring rigidity will be described later.

[0080] Specific examples will be described later, but examples of methods for making the rigidity of the dorsal extension 60 corresponding to the dorsal waist region and the ventral waist region 35 different include: different numbers of layers of sheets constituting the dorsal extension 60 and the ventral waist region 35, different basis weights and fiber densities of the materials (specifically sheets) constituting the dorsal extension 60 and the ventral waist region 35, different thicknesses of the folds of the dorsal extension 60 and the ventral waist region 35 by changing the shrinkage rate of the elastic body, different densities of heat-sealing points in the dorsal extension 60 and the ventral waist region 35, and different areas and amounts of hot-melt adhesive used in the dorsal extension 60 and the ventral waist region 35. The rigidity of the dorsal extension 60 and the ventral waist region 35 may be made different using one or more of these methods.

[0081] [Method for measuring stiffness] Peel off the side seal of the diaper, stretch and unfold it as shown in Figure 3 to spread it flat, and cut the dorsal extension 60 and the ventral waist region 35 along straight lines parallel to the width of the diaper. Roll these out in the lateral direction Y without stretching the folds that were formed naturally to form a ring-shaped sample with a diameter of 45 mm. At this time, ensure that the ring shape does not include the side reinforcement or side seal. To maintain the ring shape of the ring-shaped sample, fasten the ends of the overlapping part at two places, top and bottom, using a stapler. At this time, ensure that the stapler core is elongated in the lateral direction Y. At the overlapping part, the elastic body is fastened to the thermoplastic sheet that makes up the outer casing by the stapler. Next, cut off the excess portion to obtain a ring-shaped sample with an overlap width of about 5 mm and without the side seal or side reinforcement. The ring-shaped sample is placed in a cylindrical shape on a sample stage with its waist end facing upwards. Using a tensile testing machine (for example, the Orientec Tensilon Tensile Tester "RTA-100"), the ring-shaped sample is compressed from above at a compression speed of 10 mm / min using a flat plate positioned approximately parallel to the surface of the sample stage. The maximum load (N) is measured when the ring-shaped sample is compressed from above. This maximum load measurement is performed three times, and the average value of the maximum loads is calculated. Stiffness can be indicated by the maximum load. The larger the maximum load, the higher the stiffness can be evaluated. Note that the measurement method described here can be called a ring crush compression test, and the calculated average value of the maximum load is the ring crush compression strength when the sample is compressed in the longitudinal direction.

[0082] <Effects and Effects> The diaper 1 of this embodiment has a dorsal extension portion 60 and includes an elastic body 11F for the ventral leg that extends across the ventral portion 3 and the crotch area 9, and an elastic body 11R for the dorsal leg that extends across the dorsal portion 6 and the crotch area 9. The elastic body 11F for the ventral leg and the elastic body 11R for the dorsal leg have intermediate portions 113 and 114 that are inclined with respect to the longitudinal direction X and the transverse direction Y, respectively, when unfolded and extended.

[0083] Furthermore, diaper 1 has the above configuration (1) and configuration (2). In other words, in the diaper 1, the distance a from the ventral waist end 101 to the elastic body 11F for the ventral leg is relatively short in the ventral portion 3, and the rigidity of the ventral waist region 35 including the ventral waist end 101 is relatively low. In contrast, in the dorsal portion 6 having the dorsal extension 60, the distance b from the dorsal waist end 102 to the elastic body 11R for the dorsal leg is relatively long, and the rigidity of the dorsal extension 60 corresponding to the dorsal waist region including the dorsal waist end 102 is relatively high.

[0084] With this configuration (configuration (1) and configuration (2)), the ventral portion 3 is more susceptible to tensile forces applied to the waist end by the leg elastic body 11 in the direction toward the inner side in the lateral Y direction and the inner side in the longitudinal X direction (the direction of extension of the intermediate portions 113 and 114) than the dorsal portion 6. In this way, the ventral waist end 101 is relatively more susceptible to the tensile force of the ventral leg elastic body 11F. As a result, when wearing the diaper, the ventral waist end 101 gently and securely fits the shape of the wearer's body under the wearer's protruding abdomen, making the diaper 1 comfortable for the wearer's abdomen and less likely to slip down. On the other hand, the dorsal waist end 102 is relatively less affected by the tensile force from the elastic body 11R for the dorsal leg. As a result, the second imaginary line L2, which represents the approximate shape of the dorsal waist end 102, tends to be closer to a straight line than the first imaginary line L1, which represents the approximate shape of the ventral waist end 101. This makes it easier to secure the area of ​​the dorsal extension 60 when wearing the diaper, and effectively suppresses leakage of excrement such as soft stool from the dorsal side. In particular, the lateral Y-center of the dorsal waist end 102 of the dorsal part 6 is an area where soft stool tends to spread, but because the dorsal waist end 102 tends to be closer to a straight line, the length in the vertical X direction of the lateral Y-center of the dorsal extension 60 can be secured to be long enough to obtain a leakage suppression effect, and soft stool leakage can be effectively suppressed. Furthermore, in diaper 1, leakage can be effectively suppressed without having to design the shape of the dorsal extension portion 60 such that the length in the vertical direction X is longer in the lateral direction Y central part where soft stool tends to spread than in the sides. This reduces the area of ​​material used in the dorsal extension portion 60, which is effective in reducing material costs.

[0085] In diaper 1, having the above configurations (1) and (2), the tensile force from the leg elastic body 11 is more easily applied to the waist end of the ventral portion 3 than to the dorsal portion 6. For this reason, the ventral waist end 101 tends to have a curved shape overall, with the central part in the lateral direction Y concave downwards (inward in the vertical direction X) compared to the dorsal waist end 102. The ventral waist end 101, which tends to curve with the central part in the lateral direction Y concave downwards, tends to catch on the wearer's protruding abdomen when the diaper is worn, and tends to fit gently and securely along the wearer's body shape below the protruding abdomen, resulting in a diaper 1 that is not uncomfortable on the wearer's abdomen and does not easily slip down. Furthermore, on the dorsal side, the dorsal waist end 102 is less affected by the elastic body 11R for the dorsal leg, making it less prone to curving. As a result, when wearing the diaper, the area of ​​the dorsal extension 60 can be reliably secured, effectively suppressing leakage of excrement from the dorsal side.

[0086] The degree of curvature of the first virtual line L1, which represents the shape of the ventral waist end 101, can be expressed, for example, by the distance c in the vertical X direction between the lowest point on the first virtual line L1 (the midpoint of the lateral Y direction of the first virtual line L1 in the example shown in Figure 1) and the third virtual line L3. A larger value of distance c indicates that the first virtual line L1 has a more curved shape (a shape with greater curvature). As shown in Figure 1, in the diaper 1 of this embodiment, when a straight line is drawn connecting a pair of first points P1 on the left and right, the distance between this straight line and the lowest point on the second virtual line L2 tends to be shorter than the above distance c, and the second virtual line L2 tends to have a smaller degree of curvature than the first virtual line L1.

[0087] <Preferred rigidity of the dorsal extension (dorsal waist region) and ventral waist region> From the viewpoint of providing a diaper that is not constricting to the abdomen and has a dorsal extension that does not easily slip down, the maximum load (maximum load in the ring crush compression test described above), which serves as an indicator of the rigidity of the dorsal extension 60, is preferably 35 cN / 10 mm or more and 105 cN / 10 mm or less, and more preferably 40 cN / 10 mm or more and 100 cN / 10 mm or less. The rigidity of the ventral waist region 35 is preferably 25 cN / 10 mm or more and 85 cN / 10 mm or less, and more preferably 30 cN / 10 mm or more and 80 cN / 10 mm or less. In a diaper equipped with a dorsal extension, assuming that the dorsal extension 60 has higher rigidity than the ventral waist region 35 (higher maximum load in the ring crush compression test), the difference in maximum load between the dorsal extension 60 and the ventral waist region is preferably 7 cN / 10 mm or more and 77 cN / 10 mm or less, and more preferably 10 cN / 10 mm or more and 70 cN / 10 mm or less, from the viewpoint of ensuring that the abdomen is not constricted, that it does not slip down easily, and that leakage of excrement from the dorsal side is effectively suppressed. The values ​​listed here are calculated by converting the measured maximum load into load per 10 mm in the vertical direction of the diaper (cN / 10 mm).

[0088] When wearing the diaper, the diaper may have, in addition to the above configurations (1) and (2), one or more configurations selected from the following configurations (3) to (7), in order to make the ventral waist end of the diaper conform more easily to the shape of the wearer's body so that it fits gently and securely under the wearer's protruding abdomen on the ventral side, and to make it easier to secure the area of ​​the dorsal extension on the dorsal side to more reliably prevent leakage on the dorsal side.

[0089] By further including one or more configurations selected from configurations (3) to (7), the ventral waist end 101 becomes more easily curved than the dorsal waist end 102. As a result, when wearing the diaper, the ventral waist end 101 conforms more easily to the wearer's body shape under the wearer's protruding abdomen, making the diaper 1 less constricting on the wearer's abdomen and less likely to slip down. Also, on the dorsal side of the diaper 1, the dorsal waist end 102 becomes less easily curved than the ventral waist end 101, making it easier to more reliably secure the area of ​​the dorsal extension 60 when wearing the diaper, and thus more reliably suppressing leakage. The following describes each component.

[0090] [Composition (3)] Configuration (3) relates to the relationship between the longitudinal lengths of the elastic body for the dorsal leg and the elastic body for the ventral leg in the extended and unfolded state. As shown in Figure 4, in the unfolded and extended state, the length e2 in the longitudinal direction X of the elastic body 11R for the dorsal leg (elastic body 11Ra in this embodiment) located on the dorsal waist end 102 side may be longer than the length e1 in the longitudinal direction X of the elastic body 11F for the ventral leg (elastic body 11Fa in this embodiment) located on the ventral waist end 101 side (configuration (3)).

[0091] As shown in Figure 4, in diaper 1, the region where the inner end portion 115 of the dorsal leg elastic body 11R and the inner end portion 116 of the ventral leg elastic body 11F overlap (or are located near each other) is generally shifted ventrally in the longitudinal direction X, and the length e2 of each dorsal leg elastic body 11R in the longitudinal direction X is longer than the length e1 of each ventral leg elastic body 11F in the longitudinal direction X. The inclination angle of the intermediate portion 114 of the dorsal leg elastic body 11R with respect to the lateral direction Y is smaller than the inclination angle of the intermediate portion 113 of the ventral leg elastic body 11F with respect to the lateral direction Y, and the extension direction of the intermediate portion 114 contains a larger longitudinal X component than the extension direction of the intermediate portion 113. Therefore, the intermediate portion 113 of the ventral leg elastic body 11F is positioned such that, as you move from the outer end side towards the inner end side of the leg elastic body, and inwards in the lateral direction Y, it is further away from the waist end than the intermediate portion 114 of the dorsal leg elastic body 11R. As a result, the ventral waist end 101 is more susceptible to the tensile force of the leg elastic body 11 than the dorsal waist end 102, making the ventral waist end 101 more prone to curving. On the other hand, on the dorsal side of the diaper 1, the dorsal waist end 102 is less susceptible to the tensile force of the leg elastic body 11 than the ventral waist end 101, making the dorsal waist end 102 less prone to curving.

[0092] [Composition (4)] Configuration (4) relates to the relationship between the lateral contraction stress of the elastic body for the ventral leg and the elastic body for the dorsal leg. In diaper 1, the elastic body 11F for the ventral leg may have a higher contractile stress in the lateral direction Y than the elastic body 11R for the dorsal leg (configuration (4)). The method for measuring the contractile stress in the lateral direction Y of the elastic body 11F for the ventral leg and the elastic body 11R for the dorsal leg will be described later.

[0093] With this configuration, the ventral waist end 101 is more susceptible to the influence of the leg elastic body 11 than the dorsal waist end 102, making the ventral waist end 101 more prone to curving. On the other hand, on the dorsal side of the diaper 1, the dorsal waist end 102 is less susceptible to the influence of the leg elastic body 11 than the ventral waist end 101, making the dorsal waist end 102 less prone to curving.

[0094] (Method for measuring the contraction stress of elastic bodies for the ventral leg and the dorsal leg) Peel off the side seal of the diaper, stretch and unfold it as shown in Figure 3 to spread it flat, and cut the diaper along the extension direction of the intermediate portion of the leg elastic body (the portion inclined with respect to the lateral direction Y) to obtain a measurement sample. At this time, the measurement sample is obtained so as to include only the intermediate portion and not the inner and outer ends of the ventral leg elastic body (dorsal leg elastic body). The sample is clamped at both ends in the chuck of a tensile testing machine (SHIMADZU "Autograph AG-X"), and stretched at a speed of 300 mm / min. The length of the sample, with the leg elastic body at its maximum stretch, is set to 100. The sample is stretched to a length equivalent to 80, and then contracted to a length equivalent to 71. The tensile load (cN) at this point is measured. This measured tensile load (cN) is converted to a tensile load (cN) per unit length (10 mm). The value obtained by dividing this converted tensile load (cN) per unit length (10 mm) by the length of the sample in the X direction is taken as the contraction stress of the ventral leg elastic body (dorsal leg elastic body).

[0095] [Composition (5)] As shown in Figure 3, in the unfolded and extended state, the distance d2 in the longitudinal direction X between the second region A2 and the dorsal waist end 102, where the dorsal waist elastic body 70R and the dorsal leg elastic body 11R overlap or are located near each other, may be longer than the distance d1 in the longitudinal direction X between the first region A1 and the ventral waist end 101, where the ventral waist elastic body 70F and the ventral leg elastic body 11F overlap or are located near each other. (Configuration (5)) The above distance d1 is the distance in the longitudinal direction X between the end (transverse side) of the first region A1 closest to the ventral waist end 101 and the ventral waist end 101. The above distance d2 is the distance in the longitudinal direction X between the end (transverse side) of the second region A2 closest to the dorsal waist end 102 and the dorsal waist end 102.

[0096] The first region A1 and the second region A2 will now be explained. In Figure 3, the first region A1 and the second region A2 are indicated by dots.

[0097] As shown in Figure 3, in the unfolded and extended state of diaper 1, the first region A1 and the second region A2 are rectangular in shape, with vertical sides parallel to the vertical direction X and horizontal sides parallel to the horizontal direction Y. Distance d1 (distance d2) is the distance in the vertical direction X between the transverse side (hereinafter referred to as the "reference transverse side") located on the side of the rectangular first region A1 (second region A2) closest to the ventral waist end 101 (dorsal waist end 102) and the ventral waist end 101 (dorsal waist end 102).

[0098] The phrase "overlapping with each other or located in close proximity to each other" for the ventral waist elastic body 70F and the ventral leg elastic body 11F means that the distance between the ventral waist elastic body 70F and the ventral leg elastic body 11F in the vertical direction X is within 3 mm.

[0099] The region where the entire group of ventral leg elastic bodies, consisting of three ventral leg elastic bodies 11F, and the ventral waist elastic body 701F overlap is defined as the first region A1. In diaper 1 shown in Figure 3, the outer end portion 111 of each ventral leg elastic body 11Fa, 11Fb, and 11Fc, which is approximately parallel to the transverse direction Y, overlaps with each ventral waist elastic body 701Fb, 701Fc, and 701Fd, respectively. Also, in the example shown in Figure 3, the uppermost ventral leg elastic body 11Fa among the one or more ventral leg elastic bodies 11F and the ventral waist elastic body 701Fa located immediately above it are in a positional relationship where the vertical distance X is within 3 mm. Therefore, the elastic body 701Fa for the ventral waist is located near the elastic body 11Fa for the ventral leg, and the position of the reference transverse side of the first region A1 in the longitudinal direction X is the position of the elastic body 701Fa for the ventral waist in the longitudinal direction X. Thus, when a ventral waist elastic body 70F exists immediately above the uppermost ventral leg elastic body 11Fa among one or more ventral leg elastic bodies 11F, such that the distance in the vertical direction X from the uppermost ventral leg elastic body is greater than 0 mm and less than or equal to 3 mm, the position of the ventral waist elastic body in the vertical direction X is defined as the position of the reference horizontal edge of the first region A1. The same applies to the second region A2. The region where the entire group of elastic bodies for the dorsal legs, consisting of three dorsal leg elastic bodies 11R, and the elastic body for the dorsal waist 701R overlap is defined as the second region A2.

[0100] The first region A1 (second region A2) is a region where the outer end of the leg elastic body 11, which is almost parallel to the lateral direction Y, and the waist elastic body 70, which is also parallel to the lateral direction Y, overlap or are located in close proximity to each other, and is a "high contraction region" where the contraction stress in the lateral direction Y is relatively high.

[0101] As shown in Figure 3, in the ventral portion 3 (dorsal portion 6), there is a first region A1 (second region A2) of high contraction on each side in the lateral Y direction. Compared to a configuration without high contraction regions (a configuration where the entire leg elastic body group and the waist elastic body do not overlap), when wearing the diaper, the lateral Y center of the ventral portion 3 (dorsal portion 6) is more easily stretched by the contraction force of the first region A1 (second region A2) of high contraction on each side in the lateral Y direction. Consequently, the lateral Y center of the ventral waist end 101 (dorsal waist end 102) is more easily curved downwards.

[0102] In diaper 1, the presence of configuration (5) makes the ventral waist end 101 more susceptible to the effects of the presence of a relatively high-contraction region, while the dorsal waist end 102 is less susceptible to the effects of the presence of a relatively high-contraction region. Therefore, the ventral waist end 101 is more susceptible to the effect of the waist end curving due to the presence of the high-contraction region than the dorsal waist end 102. In other words, the presence of configuration (5) makes the ventral waist end 101 more prone to curving, and the dorsal waist end 102 less prone to curving.

[0103] [Composition (6)] Configuration (6) relates to the positional relationship between the starting position Q1 of the ventral three-dimensional gather contraction and the starting position Q2 of the dorsal three-dimensional gather contraction. As shown in Figure 4, in the unfolded and extended state of the diaper 1, the distance f2 in the vertical direction X between the dorsal three-dimensional gather contraction start position Q2 and the dorsal waist end 102 may be longer than the distance f1 in the vertical direction X between the ventral three-dimensional gather contraction start position Q1 and the ventral waist end 101 (configuration (6)).

[0104] With this configuration, the ventral waist end 101 is more susceptible to the tensile force of the elastic body 25 for three-dimensional gathering than the dorsal waist end 102, so the ventral waist end 101 is more likely to have its lateral Y-center positioned lower and be more prone to curving. On the other hand, on the dorsal side of the diaper 1, the dorsal waist end 102 is less susceptible to the tensile force of the elastic body 25 for three-dimensional gathering than the ventral waist end 101, so the dorsal waist end 102 is less prone to curving.

[0105] [Composition (7)] Configuration (7) relates to the positional relationship between the ventral fixing portion 151 and the dorsal fixing portion 152 of the three-dimensional gather G3. As shown in Figure 4, in the unfolded and extended state of the diaper 1, the distance h2 in the longitudinal direction X between the dorsal fixing portion 152 and the dorsal waist end portion 102 may be longer than the distance h1 in the longitudinal direction X between the ventral fixing portion 151 and the ventral waist end portion 101 (configuration (7)). The above distance h1 is the distance in the longitudinal direction X between the end (lateral side) of the ventral fixing portion 151 that is closer to the ventral waist end 101 and the ventral waist end 101. The above distance h2 is the distance in the longitudinal direction X between the end (lateral side) of the dorsal fixing portion 152 that is closer to the dorsal waist end 102 and the dorsal waist end 102.

[0106] By using configuration (7), the abdominal waist end 101 is more susceptible to a pulling force towards the crotch at the center of the diaper's lateral Y direction. As a result, the abdominal waist end 101 is more likely to be positioned lower at the center of the lateral Y direction and more likely to curve. On the other hand, on the dorsal side of the diaper 1, the dorsal waist end 102 is less affected by the elastic force of the three-dimensional gather elastic body 25 than the abdominal waist end 101, so the dorsal waist end 102 is less likely to curve.

[0107] <Specific examples of making the rigidity of the dorsal extension higher than that of the ventral waist region> Specific methods for making the rigidity of the dorsal extension 60 corresponding to the dorsal waist region higher than that of the ventral waist region 35 are described below as Examples 1 to 6 (Specific Examples). One or more of the methods described below can be used, and typically multiple methods are used.

[0108] By using the configurations of the first to sixth examples, the rigidity of the dorsal extension portion 60 can be adjusted to be higher than the rigidity of the ventral waist region 35. As a result, in the diaper 1, the dorsal waist end portion 102 is less likely to curve, and the ventral waist end portion 101 is relatively more likely to curve. On the dorsal side, the area of ​​the dorsal extension portion 60 is reliably secured to suppress leakage from the dorsal side, while on the ventral side, the ventral waist end portion 101 can be made to conform more easily to the shape of the wearer's body under the wearer's protruding abdomen.

[0109] [Example 1] By making the contractile stress in the lateral direction Y of the dorsal extension 60 higher than that of the ventral waist region 35, the rigidity of the dorsal extension 60 can be made higher than that of the ventral waist region 35. The method for measuring the contractile stress in the lateral direction Y of the dorsal extension 60 and the ventral waist region 35 will be described later.

[0110] The relationship between the lateral Y-stress of the dorsal extension 60 and the ventral waist region 35 can be adjusted by appropriately changing the fineness, elongation rate, number of elastic bodies, and spacing of the elastic bodies of the waist elastic body 70 placed in each of these areas. By relatively increasing the lateral Y-stress of the dorsal extension 60, the folds of the dorsal extension 60 can be made finer, thereby increasing its rigidity. The finer the folds, the easier it is to increase the thickness, making it more robust and increasing its rigidity. The higher the rigidity, the less likely the dorsal waist end 102 is to curve, making it easier to secure the area of ​​the dorsal extension 60 and achieving a leak suppression effect. On the other hand, the ventral waist region 35 has a relatively low lateral stress, making it less likely to increase in thickness. When wearing the diaper, the ventral waist end 101 fits more gently to the wearer's body shape under the wearer's protruding abdomen, resulting in a diaper 1 that is not constricting to the wearer's abdomen and is less likely to slip down.

[0111] From the viewpoint of effectively and gently fitting the ventral waist end to the body shape under the wearer's protruding abdomen and effectively suppressing leakage by securing the area of ​​the dorsal extension on the dorsal side, it is preferable to set the contraction stress of the dorsal extension 60 and the ventral waist region 35 as follows. The shrinkage stress of the dorsal extension portion 60 is preferably 20 cN / 10 mm or more and 65 cN / 10 mm or less, and more preferably 25 cN / 10 mm or more and 60 cN / 10 mm or less. The contractile stress in the ventral waist region 35 is preferably 5 cN / 10 mm to 50 cN / 10 mm, and more preferably 10 cN / 10 mm to 45 cN / 10 mm.

[0112] (Method for measuring lateral contractile stress in the dorsal extension and ventral waist region) The lateral Y-stress of the dorsal extension 60 and the ventral waist region 35 is measured as the lateral Y-stress per unit length, as follows:

[0113] ((Measurement sample)) Peel off the side seal of the diaper, stretch and unfold it as shown in Figure 3, etc., and spread it flat. Cut the ventral waist region 35 from the ventral portion 3 and the dorsal extension 60 from the dorsal portion 6 along a straight line parallel to the width direction of the diaper (lateral direction Y), obtaining strips or band-shaped samples of each part that span the entire lateral width between the side edges 54 of the ventral portion 3 and between the side edges 55 of the dorsal portion 6. When cutting, cut the entire diaper, including the absorbent body 4, not just the ventral portion 3 and dorsal portion 6, and remove the absorbent material 40. Alternatively, the dorsal extension 60 and ventral waist region 35 may be cut after removing the absorbent material 40. If an elastic body is present at the cutting location, the elastic body at that location should be positioned in the upper part, and the cut should be made in a part other than the adjacent elastic body. Record the length (mm) in the longitudinal direction X and the transverse direction Y of each cut sample.

[0114] ((Measurement of contraction stress in the Y direction)) The sample is clamped at both ends in the chuck of a tensile testing machine (SHIMADZU "Autograph AG-X"), and stretched at a speed of 300 mm / min. The length between the side seals of the ventral and dorsal sides, measured by the inner dimensions of the ventral and dorsal sides, is set to 100 (e.g., 350 mm). The sample is stretched to a length equivalent to 80 (e.g., 280 mm), and then contracted to a length equivalent to 71 (e.g., 250 mm). The tensile load (cN) at this point is measured. This measured tensile load (cN) is converted to a tensile load (cN) per unit length (10 mm). The value obtained by dividing this converted tensile load (cN) per unit length (10 mm) by the length of the sample in the X direction is taken as the contraction stress in the Y direction. The reason for defining the return force at a length equivalent to 71 when the inner dimensions of the ventral and dorsal parts are set to 100 is that the waist circumference of infants, who are the primary target of wearing the diaper 1 of this embodiment, is approximately 71% of the inner dimensions of the diaper. The waist circumference referred to here is the average value of the waist circumference measured in standing and sitting positions, taking into account the change in waist circumference when the posture of the infant changes. Each of the pair of side seals 8 (or side reinforcement parts 105) has an inner edge (inner side seal side edge 8d or inner side reinforcement part side edge 105d) located on the inside in the lateral Y direction, and the above "inner dimensions" refers to the distance between the pair of inner edges. Furthermore, the above "inner dimensions" refers to the inner dimensions when the sheet (thermoplastic sheet 50) constituting the outer body 5 is not contracted by the elastic body, in other words, when only the ventral and dorsal parts are stretched without the elastic body.

[0115] [Example 2] By making the number of layers of sheets constituting the dorsal extension 60 and the ventral waist region 35 different, specifically by making the number of layers of sheets constituting the dorsal extension 60 greater than the number of layers of sheets constituting the ventral waist region 35, the rigidity of the dorsal extension 60 can be made higher than that of the ventral waist region 35. Making the number of layers of sheets constituting the dorsal extension 60 greater than the number of layers of sheets constituting the ventral waist region 35 means, in other words, making the average basis weight of the constituent material (sheets) in the dorsal extension 60 greater than the average basis weight of the constituent material in the ventral waist region 35. The following will be explained using Figure 5(A).

[0116] As shown in Figure 5(A), the diaper 1 of this embodiment has a folded structure in which at least a part of the outer body 5 is folded back from the waist opening end Wa towards the skin-facing side. In the back portion 6 of the diaper 1 shown in Figure 5(A), the laminated outer layer sheet 51 and inner layer sheet 52 are folded back from the back waist end 102 towards the skin-facing side. In this back folded portion 6a, the outer layer sheet 51 is longer in the vertical direction X than the inner layer sheet 52, and the end of the outer layer sheet 51 in the vertical direction X is located further inward in the vertical direction X than the end of the inner layer sheet 52 in the vertical direction X. In the back portion 6, where the outer casing 5 is folded back and two layers of outer casing 5 are laminated, the two layers of outer casing 5 are bonded together with an adhesive (not shown). On the other hand, in the ventral portion 3, only the outer layer sheet 51 is folded back towards the skin from the ventral waist end 101. In other words, in the ventral folded portion 3a, the outer layer sheet 51 is present but the inner layer sheet 52 is not. In the ventral portion 3, where the outer casing 5 is folded back and two layers of outer casing 5 are laminated, the two layers of outer casing 5 are bonded together with an adhesive (not shown).

[0117] In diaper 1, as shown in Figure 5(A), due to the folded structure of the outer casing 5, the dorsal extension 60 has a first layered region R1 in which four thermoplastic sheets 50 are laminated, and the ventral waist region 35 has a second layered region R2 in which three thermoplastic sheets 50 are laminated.

[0118] In this way, by making the number of layers of sheets constituting the dorsal extension 60 (4 sheets) greater than the number of layers of sheets constituting the ventral waist region 35 (3 sheets), the rigidity of the dorsal extension 60 can be increased compared to the ventral waist region 35. As a result, in the diaper 1, the dorsal waist end 102 is relatively less prone to curving, while the ventral waist end 101 is relatively more prone to curving.

[0119] In the example shown in Figure 5(A), the ventral waist region 35 has a constant number of layers, with 3 layers across the entire lengthwise X direction. However, as shown in the example in Figure 5(B), the ventral waist region 35 may have multiple regions with different numbers of layers. In this case, the number of layers of sheets is defined as the smallest number of layers. For example, as shown in Figure 5(B), if the ventral waist region 35 has regions with 3 layers of sheets and regions with 4 layers of sheets, the number of layers of sheets constituting the ventral waist region is considered to be 3.

[0120] In both embodiments of Figure 5(A) and (B), the amount of fold-over of the inner layer sheet 52 differs between the dorsal and ventral sides of the diaper, with the dorsal side having a greater amount of fold-over than the ventral side. Furthermore, in both embodiments of Figure 5(A) and (B), the average basis weight of the constituent material (sheet) in the dorsal extension 60 is greater than the average basis weight of the constituent material in the ventral waist region 35.

[0121] [Example 3] By making at least one of the multiple sheets constituting the outer casing 5 a spunbond-meltblown-spunbond nonwoven fabric (SMS nonwoven fabric), and configuring it so that the area of ​​the SMS nonwoven fabric in the dorsal folded portion 6a of the dorsal extension 60 is larger than the area of ​​the SMS nonwoven fabric in the ventral folded portion 3a of the ventral waist region 35, the rigidity of the dorsal extension 60 can be made higher than the rigidity of the ventral waist region 35. SMS nonwoven fabric is a relatively rigid nonwoven fabric.

[0122] For example, in both the diaper 1 shown in Figures 5(A) and (B), the area of ​​the inner sheet 52 at the dorsal folded portion 6a of the dorsal extension 60 is larger than the area of ​​the inner sheet 52 at the ventral folded portion 3a of the ventral waist region 35. In such a configuration, by using a relatively rigid SMS nonwoven fabric for the inner sheet 52, the rigidity of the dorsal extension 60 can be made higher than the rigidity of the ventral waist region 35.

[0123] In other words, by using SMS nonwoven fabric for the sheet constituting the outer casing 5 which has a folded structure, and by making the amount of folding of the SMS nonwoven fabric different on the dorsal and ventral sides, the area of ​​the SMS nonwoven fabric in the dorsal folded portion 6a of the dorsal extension 60 is made larger than the area of ​​the SMS nonwoven fabric in the ventral folded portion 3a of the ventral waist region 35, thereby making the rigidity of the dorsal extension 60 higher than the rigidity of the ventral waist region 35. As a result, in the diaper 1, the dorsal waist end 102 is relatively less likely to bend, and the ventral waist end 101 is relatively more likely to bend.

[0124] [Example 4] As shown in Figure 1, the diaper 1 has a dorsal extension 60 with a pair of side reinforcing parts 105 provided on each of the pair of dorsal extension side edges 104, which increases the rigidity of the dorsal extension 60 compared to a case where the side reinforcing parts 105 are not provided. This suppresses the dorsal extension 60 from curling up during the putting motion and while wearing the diaper, and prevents the dorsal waist end 102 from curving further, thereby more reliably securing the area of ​​the dorsal extension 60 when wearing the diaper and more reliably suppressing leakage from the dorsal side.

[0125] [Example 5] The dorsal extension 60 may have a higher density of heat-sealing points between the outer sheet 51 and the inner sheet 52 that make up the outer casing 5 than the ventral waist region 35. By adopting such a configuration, the rigidity of the dorsal extension 60 can be adjusted to be higher than the rigidity of the ventral waist region 35. As a result, in the diaper 1, the dorsal waist end 102 is relatively less prone to curving, while the ventral waist end 101 is relatively more prone to curving.

[0126] [Example 6] The area of ​​hot-melt adhesive used in the dorsal extension 60 may be larger than the area of ​​hot-melt adhesive used in the ventral waist region 35. By using this configuration, the rigidity of the dorsal extension 60 can be adjusted to be higher than that of the ventral waist region 35. As a result, in the diaper 1, the dorsal waist end 102 is relatively less prone to curving, while the ventral waist end 101 is relatively more prone to curving.

[0127] 《Second Embodiment》 Referring to Figure 8, the diaper 1A of the second embodiment will be described below.

[0128] The diaper 1A of the second embodiment and the diaper 1B of the third embodiment, described later, differ from the diaper 1 of the first embodiment in that the position of the elastic body forming the waist gather G1 is different, while other configurations such as the arrangement of the leg elastic body 11 and the elastic body 25 for the three-dimensional gather are the same as those of the diaper 1 of the first embodiment. The diaper 1A of the second embodiment and the diaper 1B of the third embodiment, which has a dorsal extension 60, have the same configuration (1) to (7) as the diaper 1 of the first embodiment, and are diapers that do not feel constricting around the abdomen and do not easily slip down.

[0129] In the first embodiment and modified examples described above, we used a diaper 1 as an example, in which, as shown in Figures 5(A) and (B), there is no elastic material in the part of the dorsal portion 6 located in the iliac region of the wearer, but there is an elastic material in the part of the ventral portion 3 located near the wearer's iliac crest. In contrast, as shown in Figure 8, the diaper 1A of this embodiment (second embodiment) may be configured such that elastic bodies are placed in areas located in the wearer's iliac region on both the dorsal portion 6 and the ventral portion 3. Also, as in diaper 1A, the elastic body placed in an area of ​​the ventral portion 3 other than the ventral waist region 35 (referred to as the "first area") and the elastic body placed in an area of ​​the dorsal portion 6 opposite the first area in the thickness direction Z (referred to as the "second area") may be in substantially the same position in the longitudinal direction X. The above-mentioned first area and second area include areas located in the wearer's iliac region when worn. The same applies to the diaper 1B of the second embodiment described later. The "iliac region" mentioned above refers to the area from the iliac crest to the anterior superior iliac spine of the wearer when wearing a diaper.

[0130] As shown in Figure 8, in the ventral portion 3 of diaper 1A, the outer casing 5 is folded back towards the skin-facing side, and the upper side (waist side) of the ventral portion 3 is constructed by laminating two layers of the outer casing 5. In the ventral portion 3, the portion of the outer casing 5 that is folded back towards the skin-facing side is called the ventral folded portion 3a, and the portion of the outer casing 5 that is opposite the ventral folded portion 3a in the thickness direction Z is called the ventral opposing portion 3b. The ventral folded portion 3a and the ventral opposing portion 3b are bonded together by adhesive 19. In diaper 1A, in the ventral waist region 35, three second elastic bodies 82b are arranged in the ventral opposing portion 3b, and one second elastic body 82c is arranged in the ventral folded portion 3a. In the example shown in Figure 8, the second elastic body 82c is arranged in the upper region when the ventral waist region 35 is divided in the vertical direction X.

[0131] As shown in Figure 8, in the back portion 6 of diaper 1A, the outer casing 5 is folded back toward the skin-facing side, and the back extension portion 60 is constructed by laminating two layers of the outer casing 5. In the back portion 6, the portion of the outer casing 5 that is folded back toward the skin-facing side is called the back folded portion 6a, and the portion of the outer casing 5 that is opposite the back folded portion 6a in the thickness direction Z is called the back opposing portion 6b. The back folded portion 6a and the back opposing portion 6b are bonded together by adhesive 19. In diaper 1A, similar to diaper 1 described above, three elastic bodies (first elastic body 81a in this embodiment) are arranged in the area of ​​the back extension portion 60 of the back opposing portion 6b, and no elastic bodies are arranged in the back folded portion 6a.

[0132] In diaper 1A, elastic materials with different fineness and elongation rates are arranged in different areas. By arranging elastic materials with different fineness and elongation rates in different areas in this way, it is possible to create a diaper with a desired shrinkage stress distribution. Diaper 1A contains four types of elastic materials (1st to 4th elastic materials) with different fineness and elongation rates.

[0133] In diaper 1A, the dorsal portion 6 is provided with three first elastic bodies 81a, one first elastic body 81b, three second elastic bodies 82a, four third elastic bodies 83a, and four fourth elastic bodies 84a. The ventral portion 3 is provided with four second elastic bodies 82b, one second elastic body 82c, four third elastic bodies 83b, and four fourth elastic bodies 84b. The first elastic bodies 81a and 81b are elastic bodies with the same fineness and elongation ratio, differing only in the location where they are placed, and have the same shrinkage stress per unit; unless otherwise specified, they are referred to as the first elastic body 81. Three first elastic bodies 81a are placed in the dorsal extension portion 60, one first elastic body 81b is placed in the dorsal main body portion 61, and both first elastic bodies 81a and 81b are placed in the dorsal opposing portion 6b. The second elastic bodies 82a, 82b, and 82c are elastic bodies with the same fineness and elongation ratio, differing only in the location where they are placed, and each has the same shrinkage stress. Unless otherwise specified, they are referred to as the second elastic body 82. Three second elastic bodies 82a are placed in the dorsal main body portion 61, and three second elastic bodies 82b and one second elastic body 82c are placed in the ventral waist region 35. Three second elastic bodies 82b are placed in the ventral opposing portion 3b, and one second elastic body 82c is placed in the ventral folded portion 3a. Third elastic bodies 83a and 83b are elastic bodies with the same fineness and elongation ratio, differing only in their placement, and each has the same shrinkage stress. Unless otherwise specified, they are referred to as third elastic bodies 83. Four third elastic bodies 83a are arranged in the dorsal main body portion 61. Four third elastic bodies 83b are arranged in the ventral portion 3. The fourth elastic bodies 84a and 84b are elastic bodies with the same fineness and elongation ratio, differing only in their placement, and each has the same shrinkage stress. Unless otherwise specified, they are referred to as the fourth elastic body 84. Four fourth elastic bodies 84a are placed in the dorsal main body portion 61. Four fourth elastic bodies 84b are placed in the ventral portion 3. In the multiple elastic bodies arranged in the ventral portion 3 and the dorsal portion 6, the two lower third elastic bodies 83a of the four third elastic bodies 83a, the two lower third elastic bodies 83b of the four third elastic bodies 83b, the four fourth elastic bodies 84a, and the four fourth elastic bodies 84b are discontinuous elastic bodies, while the other elastic bodies are continuous elastic bodies. The first elastic body 81, the second elastic body 82, the third elastic body 83, and the fourth elastic body 84 have different fineness and elongation rates from each other. Furthermore, if an elastic body exists at the boundary between adjacent parts, that elastic body is considered to be located in the upper part, and the number of elastic bodies in each part is counted accordingly. The same applies to the third embodiment described later.

[0134] As shown in diaper 1A in Figure 8, each of the multiple elastic bodies arranged in the first part of the ventral part 3 (the part of the ventral part 3 other than the ventral waist region 35) may be in substantially the same position in the longitudinal direction X as each of the multiple elastic bodies arranged in the second part of the dorsal part 6 (the part of the dorsal part 6 that is opposite to the first part of the ventral part 3 in the thickness direction Z). The areas where the four third elastic bodies 83a are located on the ventral portion 3, and the areas where the four third elastic bodies 83b are located on the dorsal portion 6, are located in the iliac region of the wearer when worn.

[0135] As shown in Figure 2(A), the diaper 1A in its worn state has a substantially straight shape that slopes with respect to the vertical direction X, from top to bottom and from the dorsal side to the ventral side, along the entire side seal 8 and the side reinforcement portion 105 continuous therewith. The substantially straight shape of the side seal 8 in the worn state of the diaper 1A allows for a neat appearance. Furthermore, in the diaper 1A, the same number of elastic bodies with the same fineness and elongation rate are arranged in the ventral portion 3 and the dorsal portion 6, which are located in the iliac region of the wearer when worn. This increases the stress on the iliac region on both the ventral and dorsal sides when worn, and even when the wearer moves around vigorously after wearing, the diaper catches on the iliac bone, preventing it from slipping down on the ventral and dorsal sides, thereby effectively suppressing leakage of soft stool from the dorsal side. The same applies to the diaper 1B of the third embodiment.

[0136] In the ventral waist region 35, a virtual line is drawn to bisect the ventral waist region 35 in the vertical direction X. The area above the virtual line is called the "upper region," and the area below the virtual line is called the "lower region." In the example of diaper 1A shown in Figure 8, the second elastic body 82c is located in the upper region. In the ventral waist region 35, the upper region of the ventral waist region 35 has two elastic bodies (82b, 82c) arranged in the thickness direction Z, while the lower region of the ventral waist region 35 has one elastic body (82b) arranged in the thickness direction Z. As a result, the contraction stress in the lateral direction Y is higher in the upper region of the ventral waist region 35 than in the lower region. In this way, by placing an elastic body in the folded portion of the ventral portion 3 (ventral folded portion 3a), the contraction stress can be made different in the upper and lower regions when the ventral waist region 35 is divided in half along the vertical direction X, making it easier to adjust the contraction stress distribution in the outer casing 5.

[0137] Furthermore, as with diaper 1A, the placement of an elastic material in the ventral folded portion 3a of the ventral portion 3 can improve wearing comfort. In other words, the contractile stress near the ventral waist end 101 can be controlled not only by the fineness and elongation rate of the elastic material but also by the number of materials. Therefore, by placing an elastic material in the ventral folded portion 3a of the ventral part 3 and increasing the number of materials, the contractile stress near the ventral waist end 101 can be increased more easily. This makes it easier for the lower end 105b of the side reinforcement (upper end 8a of the side seal) to face ventrally when worn, and makes it easier for the upper end 105a of the side reinforcement to be positioned more dorsally than the lower end 105b of the side reinforcement. As a result, when wearing the diaper, for example when the wearer is lying on their side, the highly rigid side reinforcement 105 is less likely to come into contact with the side of the wearer's waist, reducing discomfort and improving wearing comfort.

[0138] Examples of fineness and elongation ratio of elastic materials are given below. However, the fineness and elongation ratio are not limited to those listed here. Each elastic material extends along the transverse direction Y and is intermittently arranged along the longitudinal direction X. The first elastic material 81 has a fineness of 470 dtex and an elongation ratio of 3.2 times. The second elastic material 82 has a fineness of 310 dtex and an elongation ratio of 2.8 times. The third elastic material 83 has a fineness of 780 dtex and an elongation ratio of 2.7 times. The fourth elastic material 84 has a fineness of 620 dtex and an elongation ratio of 2.5 times.

[0139] As shown in Figure 8, in diaper 1A, in the dorsal portion 6, four first elastic bodies (three first elastic bodies 81a and one first elastic body 81b), three second elastic bodies (three second elastic bodies 82a), and four third elastic bodies 83a are intermittently arranged at equal intervals in the vertical direction X (for example, with a pitch of 5.5 mm). In the dorsal portion 6, the spacing between the two upper fourth elastic bodies 84a and the spacing between the two lower fourth elastic bodies 84a is the same, and for example, their pitch is 5.5 mm. Regarding the elastic bodies positioned in the ventral portion 3a other than the ventral folded portion 3a, the four second elastic bodies 82b and the four third elastic bodies 83b are intermittently arranged at equal intervals (for example, a pitch of 5.5 mm) in the longitudinal direction X. In the ventral portion 3, the spacing between the two upper fourth elastic bodies 84b and the spacing between the two lower fourth elastic bodies 84b are the same, and their pitch is, for example, 5.5 mm.

[0140] Furthermore, as shown in diaper 1A in Figure 8, the dorsal end 106 and the ventral end 107 of the absorbent body 4 may be in the same position in the longitudinal direction X. This configuration allows the absorbent body 4 on the ventral side to extend to the vicinity of the ventral waist end 101, increasing the rigidity of the ventral portion 3 and making it less likely for the diaper to roll up near the ventral waist end 101. This prevents leakage due to rolling up and suppresses discomfort caused by rolling up. The same applies to the diaper 1B of the third embodiment described later.

[0141] 《Third Embodiment》 Referring to Figure 9, the diaper 1B of this embodiment (third embodiment) will be described below. In the diaper 1A of the second embodiment, an elastic material was provided only in the ventral folded portion 3a of the outer casing, and no elastic material was provided in the dorsal folded portion 6a. In contrast, as shown in Figure 9, the diaper 1B of the third embodiment may be configured in which an elastic material is provided in both the ventral folded portion 3a and the dorsal folded portion 6a of the outer casing. The following will mainly describe the differences from the diaper 1A of the second embodiment.

[0142] As shown in Figure 9, in the dorsal portion 6 of diaper 1B, two first elastic bodies 81a and one first elastic body 81c are arranged in the dorsal extension portion 60. The two first elastic bodies 81a are arranged in the dorsal opposing portion 6b, and the one first elastic body 81c is arranged in the dorsal folded portion 6a. In the dorsal main body portion 61, one first elastic body 81b, three second elastic bodies 82a, four third elastic bodies 83a, and four fourth elastic bodies 84a are arranged from top to bottom. The ventral portion 3 of diaper 1B has the same configuration as the ventral portion 3 of diaper 1B in the second embodiment. In the multiple elastic bodies arranged in the ventral portion 3 and the dorsal portion 6, the two lower third elastic bodies 83a of the four third elastic bodies 83a, the two lower third elastic bodies 83b of the four third elastic bodies 83b, the four fourth elastic bodies 84a, and the four fourth elastic bodies 84b are discontinuous elastic bodies, while the other elastic bodies are continuous elastic bodies.

[0143] The first elastic bodies 81a, 81b, and 81c differ only in their placement and location, and each has the same shrinkage stress; unless otherwise specified, they are referred to as the first elastic body 81. The second elastic bodies 82a, 82b, and 82c differ only in their placement and location, and each has the same shrinkage stress; unless otherwise specified, they are referred to as the first elastic body 81. The third elastic bodies 83a and 83b differ only in their placement, and are elastic bodies with the same fineness and elongation ratio, and each has the same shrinkage stress; unless otherwise specified, they are referred to as the third elastic body 83. The fourth elastic bodies 84a and 84b differ only in their placement, and are elastic bodies with the same fineness and elongation ratio, and each has the same shrinkage stress; unless otherwise specified, they are referred to as the fourth elastic body 84.

[0144] In the example of diaper 1B shown in Figure 9, the second elastic body 82c is positioned in the upper region when the ventral waist region 35 is divided into two equal parts in the longitudinal direction X, and the first elastic body 81c is positioned in the upper region when the dorsal extension portion 60 is divided into two equal parts in the longitudinal direction X. In the ventral waist region 35, the upper region of the ventral waist region 35 has two elastic bodies (82b, 82c) arranged in the thickness direction Z, while the lower region of the ventral waist region 35 has one elastic body (82b) arranged in the thickness direction Z. As a result, the upper region of the ventral waist region 35 has a higher contractile stress in the lateral direction Y than the lower region. Furthermore, in diaper 1B, the upper region of the dorsal extension 60 has two elastic bodies (81a, 81c) arranged in the thickness direction Z, while the lower region of the dorsal extension 60 has one elastic body (81a) arranged in the thickness direction Z. As a result, the upper region of the dorsal extension 60 has a higher contractile stress in the lateral direction Y than the lower region. In this way, by placing elastic bodies in both the dorsal portion 6 and the ventral portion 3 (dorsal folded portion 6a and ventral folded portion 3a), the contraction stress can be made different in the upper and lower regions when the ventral waist region 35 and the dorsal extension portion 60 are divided in the vertical direction X, respectively, making it easier to adjust the contraction stress distribution in the outer casing 5.

[0145] Furthermore, as with diaper 1B, the placement of elastic material in the dorsal folded portions 6a and 3a of both the ventral portion 3 and the dorsal portion 6 can further improve wearing comfort. In other words, the contraction stress near the ventral waist end 101 can be controlled not only by the fineness and elongation rate of the elastic material but also by the number of materials. Therefore, by placing an elastic material in the ventral folded portion 3a of the ventral portion 3 and increasing the number of materials, the contraction stress near the ventral waist end 101 can be increased more easily. Similarly, by placing an elastic material in the dorsal folded portion 6a of the dorsal portion 6 and increasing the number of materials, the contraction stress near the dorsal waist end 102 can be increased more easily. As a result, when worn, the position of the lower end 105b of the side reinforcement (upper end 8a of the side seal) tends to face ventrally, and the position of the upper end 105a of the side reinforcement tends to face dorsally, making it easier for the upper end 105a of the side reinforcement to be positioned further dorsally than the lower end 105b of the side reinforcement. As a result, discomfort when wearing the garment is reduced, and wearing comfort can be improved.

[0146] The fineness and elongation rates of the first to fourth elastic bodies 81 to 84 can be the same as, for example, the fineness and elongation rates of the first to fourth elastic bodies 81 to 84 of the diaper 1A of the second embodiment.

[0147] As shown in Figure 9, in the elastic bodies arranged in a manner other than the back folded portion 6a of the back portion 6, two first elastic bodies 81a, one first elastic body 81b, three second elastic bodies 82b, and four third elastic bodies 83a are intermittently arranged at equal intervals (for example, a pitch of 5.5 mm) in the vertical direction X. In the back portion 6, the spacing between the two upper fourth elastic bodies 84a and the spacing between the two lower fourth elastic bodies 84a is the same, and for example, their pitch is 5.5 mm. In the elastic bodies arranged in a manner other than the ventral folded portion 3a of the ventral portion 3, the four second elastic bodies 82b and the four third elastic bodies 83b are intermittently arranged at equal intervals (for example, a pitch of 5.5 mm) in the longitudinal direction X. In the ventral portion 3, the spacing between the two upper fourth elastic bodies 84b and the spacing between the two lower fourth elastic bodies 84b are the same, and their pitch is, for example, 5.5 mm.

[0148] Furthermore, as shown in Figure 9, in diaper 1B, similar to diaper 1A, the dorsal end 106 and the ventral end 107 of the absorbent body 4 may be in the same position in the vertical direction X.

[0149] Although embodiments of the present invention have been described above, the present invention is not limited to the embodiments described above, and various modifications can be made without departing from the spirit of the invention.

[0150] For example, the pant-type absorbent article according to the present invention does not have to be a disposable diaper for infants, but may be a disposable diaper for adults or children, for example. Furthermore, the pant-type absorbent article according to the present invention does not have to be a disposable diaper, as long as it is an absorbent article of the type worn on the lower body. Examples of such pant-type absorbent articles include pant-type sanitary napkins.

[0151] With regard to the embodiments of the present invention described above, the following additional information is disclosed. <1> A pant-type absorbent article comprising an absorbent body and an outer body positioned on the non-skin-facing side of the absorbent body, having a waist opening and a pair of leg openings, having a longitudinal direction extending from the wearer's abdominal side through the crotch to the back, and a transverse direction perpendicular to the longitudinal direction, The exterior body is, A ventral portion positioned on the wearer's abdominal side and having an ventral waist end that constitutes the waist opening, A back portion positioned on the back of the wearer, having a back waist end that constitutes the waist opening, It is positioned in the crotch area of ​​the wearer, located between the abdominal and dorsal portions, and connected to the abdominal and dorsal portions, forming the crotch area which constitutes the leg opening, It has, The dorsal waist end is located further from the pair of leg openings in the longitudinal direction than the ventral waist end, The rear side portion of the exterior body is A dorsal extension extending from the ventral waist end to the dorsal waist end in the longitudinal direction, The dorsal main body portion obtained by removing the dorsal extension portion from the dorsal portion, It has, The exterior body has a leg elastic body that forms leg gathers and is arranged circumferentially within the leg opening, The aforementioned leg elastic body is One or more elastic bodies for the back leg are arranged across the back portion and the crotch area, One or more elastic bodies for the ventral leg are arranged across the ventral portion and the crotch area, It has, In the extended and unfolded state, the elastic body for the dorsal leg and the elastic body for the ventral leg have portions that are inclined with respect to the longitudinal direction. In the unfolded and extended state, the shortest distance in the longitudinal direction from the dorsal waist end to the elastic body for the dorsal leg is longer than the shortest distance in the longitudinal direction from the ventral waist end to the elastic body for the ventral leg. The ventral portion includes the ventral waist end and has a ventral waist region that extends across the entire lateral width of the ventral portion, having the same longitudinal length as the dorsal extension. The dorsal extension has higher rigidity than the ventral waist region. Absorbent pants. <2> In the extended and unfolded state, the elastic body for the dorsal leg is longer in the longitudinal direction than the elastic body for the ventral leg. The aforementioned <1> Absorbent pant-type articles as described above. <3> The elastic body for the ventral leg has a higher lateral contraction stress than the elastic body for the dorsal leg. The aforementioned <1> or the above <2> Absorbent pant-type articles as described above. <4> The ventral portion has one or more ventral waist elastic bodies that extend laterally and are expandable in the later direction, The dorsal portion has one or more elastic bodies for the dorsal waist that extend laterally and are expandable in the later direction, In the unfolded and extended state, The ventral portion has a rectangular first region where the ventral waist elastic body and the ventral leg elastic body overlap or are located near each other. The dorsal portion has a rectangular second region where the dorsal waist elastic body and the dorsal leg elastic body overlap or are located near each other. The distance in the longitudinal direction between the end of the second region closest to the dorsal waist end and the dorsal waist end is longer than the distance in the longitudinal direction between the end of the first region closest to the ventral waist end and the ventral waist end. The aforementioned <1> ~ <3> A pant-type absorbent article described in any one of the following. <5> The absorbent body comprises an elastic body for three-dimensional gathering that forms a pair of three-dimensional gathers extending in the vertical direction along both lateral sides of the absorbent body, The three-dimensional gather has a dorsal three-dimensional gather contraction start position and a ventral three-dimensional gather contraction start position that are opposite each other in the longitudinal direction. In the unfolded and extended state, the longitudinal distance between the starting position of the dorsal three-dimensional gather contraction and the dorsal waist end is longer than the longitudinal distance between the starting position of the ventral three-dimensional gather contraction and the ventral waist end. The aforementioned <1> ~ <4> A pant-type absorbent article described in any one of the following. <6> The absorbent body is provided with three-dimensional gathers extending in the vertical direction along both sides in the horizontal direction, The three-dimensional gatherer has a leak-proof cuff and an elastic body for the three-dimensional gatherer that is placed on the leak-proof cuff. The three-dimensional gather has a dorsal fixing portion and a ventral fixing portion that are opposed to each other in the vertical direction, to which the leak-proof cuff is fixed to the absorbent body. In the unfolded and extended state, the longitudinal distance between the end of the dorsal fixing portion closest to the dorsal waist end and the dorsal waist end is longer than the longitudinal distance between the end of the ventral fixing portion closest to the ventral waist end and the ventral waist end. The aforementioned <1> ~ <5> A pant-type absorbent article described in any one of the following. <7> The dorsal extension has greater lateral contraction stress than the ventral waist region. The aforementioned <1> ~ <6> A pant-type absorbent article described in any one of the following. <8> The exterior body is constructed by laminating multiple sheets, The number of layers of the sheets constituting the dorsal extension is greater than the number of layers of the sheets constituting the ventral waist region. The aforementioned <1> ~ <7> A pant-type absorbent article described in any one of the following. <9> The exterior body is constructed by laminating multiple sheets, At least one of the multiple sheets constituting the exterior body is a spunbond-meltblown-spunbond nonwoven fabric. The dorsal extension and the ventral waist region each have a folded portion in which one end of the outer covering in the vertical direction is folded back toward the skin side. The area of ​​the spunbond-meltblown-spunbond nonwoven fabric in the folded portion of the dorsal extension is larger than the area of ​​the spunbond-meltblown-spunbond nonwoven fabric in the folded portion of the ventral waist region. The aforementioned <1> ~ <8> A pant-type absorbent article described in any one of the following. <10> The dorsal extension is, A pair of dorsal extension side edges, each facing each other in the lateral direction and extending in the longitudinal direction, A pair of side reinforcing portions provided on each of the pair of dorsal extension side edges and has The aforementioned <1> ~ <9> A pant-type absorbent article described in any one of the following. <11> The maximum load in the ring crush compression test of the dorsal extension is between 35 cN / 10 mm and 105 cN / 10 mm, and the maximum load in the ring crush compression test of the ventral waist region is between 25 cN / 10 mm and 85 cN / 10 mm. The aforementioned <1> ~ <10> A pant-type absorbent article described in any one of the following. <12> In the ring crush compression test, the maximum load is greater in the dorsal extension than in the ventral waist region, and the difference in the maximum load in the ring crush compression test between the dorsal extension and the ventral extension is between 7 cN / 10 mm and 77 cN / 10 mm. The aforementioned <1> ~ <11> A pant-type absorbent article described in any one of the following. <13> The contraction stress of the dorsal extension is preferably 20 cN / 10 mm or more and 65 cN / 10 mm or less, and the contraction stress of the ventral waist region is preferably 5 cN / 10 mm or more and 50 cN / 10 mm or less. The aforementioned <1> ~ <12> A pant-type absorbent article described in any one of the following. <14> The average basis weight of the constituent material in the dorsal extension is greater than the average basis weight of the constituent material in the ventral waist region. The aforementioned <1> ~ <13> A pant-type absorbent article described in any one of the following. <15> The exterior body is constructed by laminating an outer layer sheet and an inner layer sheet. The dorsal extension has a higher density of heat-sealing points between the outer and inner sheets than the ventral waist region. The aforementioned <1> ~ <14> A pant-type absorbent article described in any one of the following. <16> The area of ​​hot-melt adhesive used in the dorsal extension is larger than the area of ​​hot-melt adhesive used in the ventral waist region. The aforementioned <1> ~ <15> A pant-type absorbent article described in any one of the following. <17> When the aforementioned absorbent pants are worn, the same number of elastic bodies with the same fineness and elongation rate are arranged in the ventral and dorsal portions located in the iliac region of the wearer. The aforementioned <1> ~ <16> A pant-type absorbent article described in any one of the following. <18> The ventral waist region has an upper region and a lower region, which are defined by a virtual line that divides the ventral waist region in the vertical direction. The upper region has a higher lateral contraction stress than the lower region. The aforementioned <1> ~ <17> A pant-type absorbent article described in any one of the following. [Explanation of Symbols]

[0152] 1, 1A, 1B...Panty-type absorbent items (disposable diapers, diapers) 1W…Waist opening 1L... Leg opening 3...Ventral part 4… Absorbent body 5…Exterior 6...Dorsal part 8... Side seal 9... Inseam 11F... Elastic body for ventral leg 11Fa...Elastic body for the ventral leg closest to the ventral waist end. 11R... Elastic body for dorsal leg 11Ra…Elastic body for the dorsal leg, closest to the dorsal waist end. 35…Ventral waist region 60...Dorsal extension part 61...Dorsal body part 101...Ventral waist end 102...Rear waist end 113...Intermediate section (inclined section) of the elastic body for the ventral leg 114...Intermediate section (inclined section) of the elastic body for the dorsal leg a…Distance from the ventral waist end to the elastic body for the ventral leg b... Distance from the dorsal waist end to the elastic body for the dorsal leg G2... Leg area gathering

Claims

1. A pant-type absorbent article comprising an absorbent body and an outer body positioned on the non-skin-facing side of the absorbent body, having a waist opening and a pair of leg openings, having a longitudinal direction extending from the wearer's abdominal side through the crotch to the back, and a transverse direction perpendicular to the longitudinal direction, The exterior body is, A ventral portion positioned on the wearer's abdominal side and having an ventral waist end that constitutes the waist opening, A back portion positioned on the back of the wearer, having a back waist end that constitutes the waist opening, It is positioned in the crotch area of ​​the wearer, located between the abdominal and dorsal portions, and connected to the abdominal and dorsal portions, forming the crotch area which constitutes the leg opening, It has, The dorsal waist end is located further from the pair of leg openings in the longitudinal direction than the ventral waist end, The rear side portion of the exterior body is A dorsal extension extending from the ventral waist end to the dorsal waist end in the longitudinal direction, The dorsal main body portion obtained by removing the dorsal extension portion from the dorsal portion, It has, The exterior body has a leg elastic body that forms leg gathers and is arranged circumferentially within the leg opening, The aforementioned leg elastic body is One or more elastic bodies for the back leg are arranged across the back portion and the crotch area, One or more elastic bodies for the ventral leg are arranged across the ventral portion and the crotch area, It has, In the extended and unfolded state, the elastic body for the dorsal leg and the elastic body for the ventral leg have portions that are inclined with respect to the longitudinal direction. In the unfolded and extended state, the shortest distance in the longitudinal direction from the dorsal waist end to the elastic body for the dorsal leg is longer than the shortest distance in the longitudinal direction from the ventral waist end to the elastic body for the ventral leg. The ventral portion includes the ventral waist end and has a ventral waist region that extends across the entire lateral width of the ventral portion, having the same longitudinal length as the dorsal extension. The dorsal extension has higher rigidity than the ventral waist region. Absorbent pants.

2. In the extended and unfolded state, the elastic body for the dorsal leg is longer in the longitudinal direction than the elastic body for the ventral leg. The pant-type absorbent article according to claim 1.

3. The elastic body for the ventral leg has a higher lateral contraction stress than the elastic body for the dorsal leg. The pant-type absorbent article according to claim 1 or 2.

4. The ventral portion has one or more ventral waist elastic bodies that extend laterally and are expandable in the later direction, The dorsal portion has one or more elastic bodies for the dorsal waist that extend in the lateral direction and are expandable in the lateral direction, In the unfolded and extended state, The ventral portion has a rectangular first region where the ventral waist elastic body and the ventral leg elastic body overlap or are located near each other. The dorsal portion has a rectangular second region where the dorsal waist elastic body and the dorsal leg elastic body overlap or are located near each other. The distance in the longitudinal direction between the end of the second region closest to the dorsal waist end and the dorsal waist end is longer than the distance in the longitudinal direction between the end of the first region closest to the ventral waist end and the ventral waist end. The pant-type absorbent article according to claim 1 or 2.

5. The absorbent body comprises an elastic body for three-dimensional gathering that forms a pair of three-dimensional gathers extending in the vertical direction along both lateral sides of the absorbent body, The three-dimensional gather has a dorsal three-dimensional gather contraction start position and a ventral three-dimensional gather contraction start position that are opposite each other in the longitudinal direction. In the unfolded and extended state, the longitudinal distance between the starting position of the dorsal three-dimensional gather contraction and the dorsal waist end is longer than the longitudinal distance between the starting position of the ventral three-dimensional gather contraction and the ventral waist end. The pant-type absorbent article according to claim 1 or 2.

6. The absorbent body is provided with three-dimensional gathers extending in the vertical direction along both sides in the horizontal direction, The three-dimensional gatherer has a leak-proof cuff and an elastic body for the three-dimensional gatherer that is placed on the leak-proof cuff. The three-dimensional gather has a dorsal fixing portion and a ventral fixing portion that are opposed to each other in the vertical direction, to which the leak-proof cuff is fixed to the absorbent body. In the unfolded and extended state, the longitudinal distance between the end of the dorsal fixing portion closest to the dorsal waist end and the dorsal waist end is longer than the longitudinal distance between the end of the ventral fixing portion closest to the ventral waist end and the ventral waist end. The pant-type absorbent article according to claim 1 or 2.

7. The dorsal extension has greater lateral contraction stress than the ventral waist region. The pant-type absorbent article according to claim 1 or 2.

8. The exterior body is constructed by laminating multiple sheets, The number of layers of the sheets constituting the dorsal extension is greater than the number of layers of the sheets constituting the ventral waist region. The pant-type absorbent article according to claim 1 or 2.

9. The exterior body is constructed by laminating multiple sheets, At least one of the multiple sheets constituting the exterior body is a spunbond-meltblown-spunbond nonwoven fabric. The dorsal extension and the ventral waist region each have a folded portion in which one end of the outer covering in the vertical direction is folded back toward the skin side. The area of ​​the spunbond-meltblown-spunbond nonwoven fabric in the folded portion of the dorsal extension is larger than the area of ​​the spunbond-meltblown-spunbond nonwoven fabric in the folded portion of the ventral waist region. The pant-type absorbent article according to claim 1 or 2.

10. The dorsal extension is, A pair of dorsal extension side edges, each facing each other in the lateral direction and extending in the longitudinal direction, A pair of side reinforcing portions provided on each of the pair of dorsal extension side edges and has The pant-type absorbent article according to claim 1 or 2.

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