CN112566596A

CN112566596A - Disposable diaper having a disposable diaper

Info

Publication number: CN112566596A
Application number: CN201980053034.8A
Authority: CN
Inventors: 市原拓巳; 坂口智; 山中康弘; 高桥真衣香
Original assignee: Unicharm Corp
Current assignee: Unicharm Corp
Priority date: 2018-08-14
Filing date: 2019-08-07
Publication date: 2021-03-26
Anticipated expiration: 2039-08-07
Also published as: TW202019363A; TWI798477B; JP2020025789A; WO2020036113A1; JP7089985B2; CN112566596B

Abstract

Provided is a disposable diaper which can ensure the fit between the crotch of the body and also the fit between the hip of the wearer, and which can suppress leakage. A disposable diaper (10) is provided with an absorbent core (31) disposed at least in the crotch region, and a pair of crotch stretch units (41) disposed on both outer sides of the center in the width direction of the absorbent core and extending in the front-rear direction. The absorbent core has a narrow portion (35) which is shorter than the front and rear portions in the width direction. At least a part of the crotch stretch unit is disposed at the narrower section on the inner side in the width direction than the outer edge of the absorbent core. The rear end edge (41R) of the crotch stretch unit (41) is disposed on the front side of the rear end edge (35R) of the narrow section (35).

Description

Disposable diaper having a disposable diaper

Technical Field

The present invention relates to a disposable diaper having a pair of crotch stretch units extending in a front-rear direction in a crotch region.

Background

A disposable diaper having a pair of crotch stretch units extending in the front-rear direction in a crotch region is known (see, for example, patent document 1). The crotch stretch unit is disposed in a region overlapping the absorbent core. The crotch stretch unit contracts to pull up the absorbent core in the crotch region toward the body side.

In addition, the absorbent core of patent document 1 is formed with a pair of groove portions extending in the front-rear direction. The groove-like portion serves as a deformation base point of the absorbent core. When the disposable diaper having such a structure is put on, the absorbent core deforms from the groove-like portion as a starting point, and the absorbent core overlapping the crotch stretch unit is pulled up toward the body.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2018-473

Disclosure of Invention

However, the above-described disposable diaper has the following problems.

The disposable diaper is worn so as to cover the abdomen from the buttocks of the wearer. The shape of the body of the disposable diaper is narrowest between the thighs, and bulges outward in the width direction from the thighs toward the buttocks. In the case of the disposable diaper of patent document 1, the absorbent core pulled up by contraction of the crotch stretch unit is pulled up relative to the crotch of the wearer. However, since the crotch stretch unit extends from the crotch to the hip in parallel with the front-back direction, the absorbent core is pulled up against the hip as well as the crotch. Therefore, when the deformation of the absorbent core that fits between the wearer's thighs is also associated with the rear body area, the disposable diaper does not fit the buttocks, and leakage may occur.

Accordingly, a disposable diaper is desired which can secure fit between the crotch of the body and also secure fit between the hip and the hip, and can suppress leakage.

A disposable diaper according to one aspect comprises: a front-back direction and a width direction orthogonal to each other; a front torso-surrounding region, a rear torso-surrounding region, and a crotch region disposed between the front torso-surrounding region and the rear torso-surrounding region; an absorbent core disposed in at least the crotch region; and a pair of crotch stretch units disposed on both outer sides of the center of the absorbent core in the width direction and extending in the front-rear direction, wherein the absorbent core has a narrow portion whose length in the width direction is shorter than the front portion and the rear portion, at least a part of the crotch stretch unit is disposed on the inner side of the narrow portion in the width direction than the outer edge of the absorbent core, and the rear end edge of the crotch stretch unit is disposed on the front side of the rear end edge of the narrow portion.

Drawings

Fig. 1 is a plan view of a disposable diaper according to an embodiment, as viewed from the skin surface side.

Fig. 2 is a top view of an absorbent core of an embodiment.

Fig. 3 is a schematic sectional view of the disposable diaper shown in fig. 1 taken along the section a-a.

Fig. 4 is a schematic sectional view of the disposable diaper shown in fig. 1 taken along the section B-B.

Fig. 5 is a schematic sectional view of the disposable diaper shown in fig. 1, taken along the C-C section.

Fig. 6 is a view schematically showing a worn state of a disposable diaper at a section a-a.

Fig. 7 is a view schematically showing a worn state of the disposable diaper according to the embodiment.

Fig. 8 is a view for explaining a deformed state of the absorbent core when worn.

FIG. 9 is a view for explaining a modified form of the absorber at a B-B section of the disposable diaper.

Detailed Description

(1) Brief description of the embodiments

At least the following matters will be made clear by the description of the present specification and the accompanying drawings.

A disposable diaper in one form includes: a front-back direction and a width direction orthogonal to each other; a front body surrounding region, a rear body surrounding region, and a crotch region arranged between the front body surrounding region and the rear body surrounding region; an absorbent core disposed at least in the crotch region; and a pair of crotch stretch units disposed on both outer sides of the center of the absorbent core in the width direction and extending in the front-rear direction, wherein the absorbent core has a narrowed portion whose length in the width direction is shorter than the front portion and the rear portion, at least a part of the crotch stretch unit is disposed on the inner side of the narrowed portion in the width direction than the outer edge of the absorbent core, and the rear end edge of the crotch stretch unit is disposed on the front side of the rear end edge of the narrowed portion.

In this configuration, the absorbent core in the crotch region is pulled up toward the body by contraction of the crotch stretch unit. The pair of crotch stretch units are located on both outer sides of the center in the width direction, and the region overlapping the crotch stretch unit is pulled up by contraction of the crotch stretch unit, and the region sandwiched by the crotch stretch units is pulled up while maintaining a flat shape along the body. The pair of crotch stretch units are positioned inward in the width direction of the outer edge of the absorbent core, and the region between the pair of crotch stretch units is pulled up toward the body side with respect to the region outward in the width direction of the crotch stretch units. This ensures fit between the crotch and the body. When the region between the pair of crotch stretch units is pulled up toward the body, the narrower section is pulled inward in the width direction in the region where the narrower section and the crotch stretch unit overlap in the width direction, and a fold line is formed that connects the rear end edge of the crotch stretch unit and the rear end edge of the narrower section. The deformation caused by the pair of crotch stretch units is guided to the side edges of the absorbent core along the above folding lines, and the transmission of the deformation caused by the crotch stretch units to the rear body region can be suppressed. The adhesive force to the buttocks can be ensured, and the rear leakage can be suppressed. Further, by forming a folding line connecting the rear end edge of the crotch stretch unit and the rear end edge of the narrow portion, deformation such that the distance of the folding line becomes shorter is suppressed, and the deformation is opposed to a force that moves the rear end edge of the narrow portion inward in the width direction. This makes it difficult for the rear end edge of the narrow portion to move inward in the width direction, and the width of the absorbent core in the rear body surrounding region can be ensured. This enables the buttocks to be covered with a wide area by the absorbent core, and leakage can be suppressed.

According to a preferred aspect, the front end edge of the crotch stretch unit may be disposed rearward of the front end edge of the narrow portion. In this configuration, when the region between the pair of crotch stretch units is deformed into a convex shape, the fold line connecting the front end edge of the crotch stretch unit and the front end edge of the narrow portion is also formed. The deformation of the crotch stretch unit can be suppressed from being transmitted to the front body region. Can ensure the adhesion with abdomen and inhibit front leakage. Further, the folding line connecting the front end edge of the crotch stretch unit and the front end edge of the narrow portion opposes the force moving the front end edge of the narrow portion inward in the width direction, and the width of the absorbent core in the front body surrounding region can be secured. This enables the abdomen to be covered with a wide area by the absorbent core, and leakage can be suppressed.

According to a preferred aspect, the distance between the crotch stretch unit and the outer edge of the absorbent core may be equal to or longer than 1/4 of the length between the outer edges of the absorbent core. In this aspect, when the crotch stretch unit is deformed to a convex shape toward the body side from the crotch stretch unit as a base point, the region on the outer side in the width direction than the crotch stretch unit becomes a region for supporting the convex deformation. Since the region outside the crotch stretch unit in the width direction is equal to or more than 1/4 of the entire region of the absorbent core in the width direction, the convex deformation is stably supported, and the convex shape is easily maintained. Further, the rigidity of the region outside the crotch stretch unit in the width direction is improved, so that the narrowed portion of the absorbent core is not excessively deformed into a convex shape, and the area of the body covered with the absorbent core can be secured. Leakage is more suppressed by covering the body with a wide area by the absorbent core.

According to a preferred aspect, the disposable diaper may have a pair of side sheets arranged on the skin surface side of the absorbent core and covering the outer side portion of the absorbent core, the side sheets may form a pair of leakage preventing gathers having a contracted portion which rises due to contraction of a leakage preventing elastic member and a base point portion which serves as a rising fulcrum of the contracted portion at a position outside the contracted portion in the width direction, and a distance between an apex of the contracted portion and the base point portion in the width direction may be longer than a distance between the outer edge of the absorbent core at the narrow portion and the crotch stretch portion in the width direction. In this mode, the leakage preventing gathers rise toward the wearer side with the contracted portion as the apex due to contraction of the leakage preventing elastic member. The maximum height of the leak-proof fold when standing up becomes the distance between the apex of the constricted portion and the base point portion in the width direction. The maximum height of the convex deformation in the region where the narrowed portion is provided is the distance between the outer edge of the narrowed portion of the absorbent core and the crotch stretch unit. Since the distance between the apex of the contracted portion and the base point portion is longer than the distance between the outer edge of the narrowed portion of the absorbent core and the crotch stretch portion, the height of the leakage preventing gathers is higher than the height of the convex deformation, and side leakage can be suppressed by the leakage preventing gathers.

According to a preferred aspect, the crotch stretch unit may have a 1 st crotch stretch unit disposed on one side with respect to a center in a width direction of the absorbent core and a 2 nd crotch stretch unit disposed on the other side with respect to the center in the width direction of the absorbent core, the 1 st crotch stretch unit and the 2 nd crotch stretch unit may each have a plurality of elastic members disposed at intervals in the width direction, and a distance between the elastic members of the 1 st crotch stretch unit and a distance between the elastic members of the 2 nd crotch stretch unit may be 3 times or less a thickness of the absorbent core. In this mode, by providing the 1 st and 2 nd crotch stretch units with a plurality of elastic members, respectively, the force of pulling up the absorbent core is increased, and the convex shape of the absorbent core is more easily maintained. Further, when the distance between the elastic members is more than 3 times the thickness of the absorbent core, the elastic members may pull up the absorbent core independently, and the elastic members may not pull up the absorbent core integrally. Since the distance between the elastic members is 3 times or less the thickness of the absorbent core, the absorbent core can be pulled up integrally by the plurality of elastic members of the 1 st crotch stretch unit, and the absorbent core can be pulled up integrally by the plurality of elastic members of the 2 nd crotch stretch unit. This makes it easier to form the convex shape of the absorbent core.

According to a preferred aspect, the absorbent core in the crotch region may be provided with a high rigidity portion having higher rigidity than the surrounding region between the pair of crotch stretch units, the high rigidity portion extending across the center of the absorbent core in the width direction. In this mode, the high rigidity portion can increase the rigidity, and the absorbent core can easily have a planar shape along the body. The area between the pair of crotch stretch units is not excessively deformed to a convex shape, and the area of the body covered with the absorbent core can be ensured. Further, since the high rigidity portion is provided across the center in the width direction of the absorbent core, the absorbent core can be arranged along the excretory opening of the body with respect to the excretory opening, so that the drawing-in property of the body fluid can be improved, and leakage can be suppressed.

According to a preferred aspect, the rear body region may include a waist stretchable portion which is stretchable at least in the width direction, and the waist stretchable portion may be disposed in a region overlapping with the absorbent core at a position rearward of the narrow portion and outward of the crotch stretchable portion in the width direction. In this configuration, as described above, the folding line extending from the rear end edge of the crotch stretch unit reaches the rear end edge of the narrow portion. The fold line opposes a force that moves the rear end edge of the narrow portion inward in the width direction, so that the rear end edge of the narrow portion is less likely to move inward in the width direction. The length of the absorbent core in the width direction of the region overlapping the waist elastics is shortened by contraction of the waist elastics. At this time, the region located rearward of the narrow portion and outward in the width direction of the crotch stretch unit is easily deformed inward in the width direction from the rear end edge of the narrow portion by contraction of the waist stretch unit. At this time, the rear end edge of the narrow portion becomes a deformation base point and is less likely to move inward in the width direction. The rear end edge of the narrow portion located on the rear side of the crotch stretch unit is less likely to move inward in the width direction, and the length of the absorbent core in the width direction in the rear body surrounding region is more likely to be secured, and back leakage can be suppressed.

According to a preferred aspect, the waist stretchable unit may have a 1 st region and a 2 nd region having a higher elongation in the width direction than the 1 st region, and the 1 st region may be disposed on a 1 st extension line extending rearward from the rear end edge of the crotch stretchable unit. In this aspect, since the 1 st region is provided on the 1 st extension line extending from the rear end edge of the crotch stretch unit to the rear side, the region deformed into a convex shape by contraction of the crotch stretch unit is less likely to be reduced in the width direction by contraction of the waist stretch unit, and the convex deformed state is easily maintained.

According to a preferred aspect, the 2 nd region may be disposed on a 2 nd extension line extending rearward from a region outside the crotch stretch unit in the width direction. In this mode, since the 2 nd region is provided on the 2 nd extension line, the region of the absorbent core outside the crotch stretch unit in the width direction is more likely to deform inward in the width direction from the rear end edge of the narrowed portion. The rear end edge of the narrow portion located on the rear side of the crotch stretch unit is less likely to move inward in the width direction, and the length of the absorbent core in the width direction in the rear body surrounding region is more likely to be secured, and back leakage can be suppressed.

According to a preferred aspect, the disposable diaper may include a fastening tape disposed in the rear body surrounding region and having a joint portion joined to the front body surrounding region, and a leg hole stretch unit that stretches and contracts in the front-rear direction at a position outside the absorbent core in the width direction, and the leg hole stretch unit may be disposed on a 1 st imaginary line connecting a front end edge of an inner edge of the joint portion and a rear end edge of the crotch stretch unit. In this form, when the fastening tape is pulled, the force pulling outward in the width direction acts along the 1 st imaginary line connecting the front end edge at the inner edge of the joint portion and the rear end edge of the crotch stretch portion. The rear end edge of the crotch stretch unit is pulled outward in the width direction by the operation during wearing, and the absorbent core deformed into a convex shape toward the body side by the crotch stretch unit is also pulled outward in the width direction. This suppresses the absorbent core from being deformed convexly inward in the width direction, and the convexly deformed state is easily maintained. Further, the leg hole stretch units are arranged on the 1 st imaginary line, and the leg hole stretch units can be pulled up even when the wearer wears the garment. This improves the fit to the crotch excretory opening and the fit to the leg band, and further suppresses leakage.

According to a preferred aspect, the disposable diaper may include a fastening tape disposed in the rear body surrounding region and having a coupling portion coupled to the front body surrounding region, wherein the absorbent core on the rear side of the crotch stretch unit is provided with a pair of deformation base point portions extending toward the rear side and toward the outside in the width direction and disposed at an interval in the width direction, the deformation base point portions being disposed on the inner side in the width direction than a 2 nd imaginary line connecting a rear end edge of the crotch stretch unit and a rear end edge of the narrow portion. In this configuration, the 2 nd virtual line connecting the rear end edge of the crotch stretch unit and the rear end edge of the narrow portion becomes a folding line opposing the force moving the rear end edge of the narrow portion inward in the width direction, and the region sandwiched by the folding lines is arranged so as to cover the body. The deformation base point portion deforms at a position on the rear side of the crotch stretch unit in this region. The base deformation point portion extends toward the rear side and outward in the width direction, and the absorbent core is formed with base deformation points extending inward in the width direction from the rear body surrounding region toward the crotch region. In order to put on a belt-type disposable diaper, when the rear body region is put on the buttocks and the diaper is pulled toward the crotch region, the absorbent core is deformed at a base point extending inward in the width direction from the rear body region toward the crotch region. This allows the absorbent core to be deformed so that the length in the width direction decreases toward the crotch region. The absorbent core in the crotch region is deformed into a convex shape toward the body side by contraction of the pair of crotch stretch units. Thereby, the absorbent core in the crotch region is disposed along the body side. This allows the absorbent core to be appropriately accommodated in the crotch of the wearer. The absorbent core can be covered over the wearer's buttocks in a wide area, and can be compactly stored in the gap between the wearer's legs. The absorbent core is conformable from the wearer's hips to the crotch region, and is more resistant to leakage.

According to a preferred aspect, an angle of the 2 nd virtual line with respect to the width direction may be smaller than an angle of the deformation base point portion with respect to the width direction. In this mode, since the angle of the 2 nd virtual line with respect to the width direction is small, the movement of the rear end edge of the narrow portion to the inside in the width direction can be further suppressed, and the width of the absorbent core in the rear body surrounding region can be further secured. Further, since the angle of the deformation origin point portion with respect to the width direction is relatively large, the region sandwiched by the 2 nd virtual line can be locally deformed, and the body can be covered with the region outside the deformation origin point portion in the width direction. Thus, the absorbent core can cover the buttocks with a wide area, and can suppress leakage.

(2) Overall schematic structure of disposable diaper

Hereinafter, a disposable diaper according to an embodiment will be described with reference to the drawings. In the description of the drawings below, the same or similar parts are denoted by the same or similar reference numerals. However, it should be noted that the drawings are schematic drawings, and the ratio of the dimensions and the like are different from those in the actual case. Therefore, specific dimensions and the like should be determined with reference to the following description. In addition, the drawings may include portions having different dimensional relationships and ratios from each other.

The disposable diaper may be a tape-type disposable diaper or a pants-type disposable diaper. Fig. 1 is a plan view of a disposable diaper 10 according to the present embodiment as viewed from the skin surface side, and fig. 2 is a plan view of an absorbent core according to the embodiment as viewed from the skin surface side. The plan views shown in fig. 1 and 2 show the disposable diaper in an extended state. Fig. 3 is a schematic sectional view of the disposable diaper shown in fig. 1 taken along the section a-a. Fig. 4 is a schematic sectional view of the disposable diaper shown in fig. 1 taken along the section B-B. Fig. 5 is a schematic sectional view of the disposable diaper shown in fig. 1, taken along the C-C section. The extended state in the present invention is a state in which the disposable diaper 10 is extended to a state in which no wrinkles are formed. In the present invention, the natural state is a state in which, in the case of the disposable diaper 10 contained in the package, the disposable diaper 10 is taken out of the package and left to stand in an environment of 20 ℃ ± 2 ℃ and a relative humidity of 60% ± 5% RH for 24 hours.

The disposable diaper 10 has a front-back direction L and a width direction W orthogonal to each other. The front-back direction L is defined by a direction extending to the front side and the back side of the body. In other words, the front-back direction L is a direction extending in the front-back direction on the disposable diaper 10 after being unfolded. The disposable diaper 10 has a thickness direction T orthogonal to both the front-back direction L and the width direction W. The thickness direction T extends toward the skin surface side T1 on the wearer side and toward the non-skin surface side T2 on the side opposite to the skin surface side.

The disposable diaper 10 has a front body surrounding region S1, a rear body surrounding region S2, and a crotch region S3. The front waistline region S1 is a region opposed to the front waistline (abdomen) of the wearer. The rear torso-surrounding region S2 is a region opposed to the rear torso (back) of the wearer, and includes a region for supporting the body (buttocks) when worn. The crotch region S3 is a region located in the crotch of the wearer and disposed between the front body surrounding region S1 and the rear body surrounding region S2. The crotch region S3 is a region provided with leg hole openings arranged around the legs of the wearer. The leg hole openings are portions recessed inward in the width direction from the outer edge of the disposable diaper.

The disposable diaper 10 comprises an absorbent core 31, the absorbent core 31 comprising an absorbent material. The absorbent core 31 contains absorbent material such as comminuted pulp or superabsorbent polymers (SAP) or mixtures of these. As shown in fig. 3, the absorbent core 31 may be covered by a core wrap sheet 32. The absorbent body 30 can be constituted by the absorbent core 31 and the core wrap 32. The core wrap 32 may be made of a paper towel, and is disposed on the skin surface side T1 of the absorbent core 31 and the non-skin surface side T2 of the absorbent core 31.

As shown in fig. 1 and 3, the topsheet 21 and the side sheet 22 may be provided on the skin surface side T1 of the absorbent body 30 including the absorbent core 31. The topsheet 21 may be arranged across the center of the absorber 30 in the width direction W. The side sheets 22 may be arranged in a pair so as to cover the front sheet 21 and the outer side of the absorbent core 31. The front sheet 21 and the side sheets 22 may be made of a liquid-permeable sheet such as a nonwoven fabric or an apertured plastic film. The inner side portions of the side sheets 22 may be folded back to be overlapped. A leakage-preventing stretchable portion 43 stretchable in the front-rear direction L may be provided between the overlapped side sheets 22. The leakage preventing stretchable portion 43 may be formed of a rubber thread stretchable in the front-rear direction L. The side sheet 22 and the leakage preventing stretchable parts 43 constitute leakage preventing gathers 60 (see fig. 6) rising toward the skin surface side T1 when worn. As shown in fig. 1 and 3, the leakage preventing gathers 60 have contracted portions 61 that rise due to contraction of the leakage preventing stretchable and contractible portions 43, and base point portions 62 that serve as rising fulcrums of the contracted portions at positions outside the contracted portions 61 in the width direction W. The side sheet 22 is joined to the front sheet 21 at the base point 62. The side sheet 22 is configured not to be joined to the front sheet 21 at a position inward in the width direction of the base point portion 62, and can be raised with respect to the front sheet 21.

The back sheet 23 and the outer sheet 24 may be provided on the non-skin surface side T2 of the absorbent body 30. The exterior sheet 24 may be provided on the non-skin surface side T2 of the back sheet 23. The length of the back sheet 23 in the width direction W may be shorter than the length of the exterior sheet 24 in the width direction W, and the length of the back sheet 23 in the front-rear direction L may be shorter than the length of the exterior sheet 24 in the front-rear direction L. The back sheet 23 may be formed of a liquid-impermeable film. The outer sheet 24 may be made of a liquid-permeable nonwoven fabric.

A fastening tape 91 is provided on the outer side of the rear body surrounding region. The fastening tape 91 has a base portion 92 and a joining portion 93. The base portion 92 is disposed between the exterior sheet 24 and the side sheet 22 in the thickness direction T, and extends outward from the exterior sheet 24 and the side sheet 22 in the width direction W. The coupling portion 93 is disposed on the base portion 92 and coupled to a target portion 95 (see fig. 5). The target portions 95 are arranged in the width direction at intervals in the front body surrounding region S1, and are configured to be fixed by the fastening tapes 91, respectively.

The presentation section 51 may be disposed between the back sheet 23 and the absorber 30. The presentation part 51 may be disposed on the non-skin surface side T2 with respect to the absorbent core 31. The presentation portions 51 may extend in the front-rear direction L and be arranged with a space in the width direction W. The presentation unit 51 is disposed between the low basis weight units 33 described later. The presentation unit 51 is configured to be discolored by absorption of body fluid by the absorber 30, and can grasp the absorption state of body fluid from the non-skin surface side T2 of the disposable diaper 10.

The disposable diaper 10 may have a leg hole stretch unit 42 that stretches and contracts in the front-rear direction at a position outside the absorbent core 31 in the width direction. The leg hole stretch units 42 may be provided between the side sheet 22 and the back sheet 23 and between the side sheet 22 and the exterior sheet 24. The leg hole stretch units 42 are formed of band-shaped stretch pieces that stretch in the front-rear direction L. By contraction of the leg hole stretch units 42, the leg hole openings of the disposable diaper 10 are brought into contact with the leg holes when the disposable diaper 10 is worn.

The disposable diaper 10 may have a waist stretchable unit 45 stretchable at least in the width direction in the rear body region. The waist stretchable panel 45 extends in the width direction W along the rear end edge of the disposable diaper. The waist stretch units 45 may be provided between the back sheet 23 and the exterior sheet 24, between the front sheet 21 and the exterior sheet 24, and between the side sheets 22 and the exterior sheet 24. The rear end edge of the waist stretchable panel 45 may be positioned on the front side of the rear end edge of the disposable diaper, and the front end edge of the waist stretchable panel 45 may be positioned on the front side of the rear end edge of the absorbent core 31. The waist elastics 45 may extend outward in the width direction W from the absorbent core 31. The waist stretchable unit 45 is formed of a band-shaped stretchable sheet stretchable in the width direction W.

The disposable diaper 10 may have a pair of crotch stretch units 41 provided in a region overlapping the absorbent core 31 in the crotch region. The crotch stretch unit 41 may be disposed on the non-skin surface side of the absorbent core 31 or may be disposed on the non-skin surface side of the absorbent body 30. The crotch stretch unit 41 may be disposed between the absorbent core 31 and the back sheet 23, between the core wrap sheet 32 disposed closer to the non-skin surface side T2 than the absorbent core 31 and the back sheet 23, between the core wrap sheet 32 disposed closer to the non-skin surface side T2 than the absorbent core 31 and the absorbent core 31, or between the back sheet 23 and the outer sheet 24. The crotch stretch unit 41 of the present embodiment is disposed between the back sheet 23 and the exterior sheet 24. The crotch stretch unit 41 extends in the front-rear direction L and is disposed at intervals in the width direction W. The crotch stretch unit 41 is not disposed at the center of the absorbent core 31 in the width direction W, but two crotch stretch units 41 are disposed on both sides of the center of the absorbent core 31 in the width direction W. Thus, the absorbent core in the region overlapping the crotch stretch unit 41 is pulled up to a position closer to the body than the center in the width direction of the absorbent core by the contraction of the crotch stretch unit 41. The pair of crotch stretch units 41 may be positioned inward in the width direction from the outer edge of the absorbent core 31. The region located between the pair of crotch stretch units 41 is pulled up toward the body side with respect to the region located outside the pair of crotch stretch units 41 in the width direction. Thus, the center of the absorbent core in the width direction can be deformed into a convex shape with the side portions as base points, and fit between the crotch of the body can be secured. The crotch stretch unit 41 may include: a 1 st crotch stretch unit 411 disposed on one side with respect to the center in the width direction W of the absorbent core 31; and a 2 nd crotch stretch unit 412 disposed on the other side with respect to the center in the width direction W of the absorbent core 31. Each of the 1 st crotch stretch unit 411 and the 2 nd crotch stretch unit 412 has a plurality of elastic members arranged at intervals in the width direction W. The crotch stretch unit 41 is formed of a rubber thread arranged in the front-rear direction L. In another embodiment, the crotch stretch unit 41 may be formed of a belt-like stretch sheet which stretches in the front-rear direction, may be formed of 1 rubber thread, or may be formed of 3 or more rubber threads. In the present invention, the overlapped state refers to a state in which one member is overlapped with another member in a plan view, and is a state in which another member is disposed on a skin surface side or a non-skin surface side of one member. The overlapped state includes not only a state in which one member and the other member are in contact with each other but also a structure in which the other member is interposed between the one member and the other member.

The crotch stretch unit 41 may extend across the center 10LC of the disposable diaper in the front-back direction. The center 10LC in the front-back direction of the disposable diaper can be pulled up toward the body by contraction of the crotch stretch unit 41. In particular, in a state where the skin surface sides of the disposable diaper before use are folded in two so as to face each other, the fold due to the folding can be pulled up. At least a part of the crotch stretch unit 41 is positioned inward in the width direction W of the narrower section 35, which will be described later, from the outer edge of the absorbent core 31. At least a part of the crotch stretch unit 41 is disposed within the narrow portion 35 in the front-rear direction. The rear end edge 41R of the crotch stretch unit 41 is disposed forward of the rear end edge 35R of the narrower portion 35. The front end edge 41F of the crotch stretch unit 41 may be disposed rearward of the front end edge 35F of the narrower portion 35. A region in which the contraction force of the crotch stretch unit 41 is less likely to act is provided on the absorbent core 31 at a position outside the crotch stretch unit 41 in the width direction W. Shown in fig. 3: a side region R31 located outside the crotch stretch unit 41 in the absorbent core 31; and a central region R32 between the side regions R31. The side region R31 is a region located outward in the width direction W from the crotch stretch unit 41 located outermost in the width direction W. The central region R32 is a region obtained by combining a region overlapping the crotch stretch unit 41 and a region located inward in the width direction W from the crotch stretch unit 41. The central region R32 is pulled up toward the body side with respect to the side regions R31 by contraction of the crotch stretch unit 41. The deformed form of the absorbent core 31 when worn is explained in detail in the following description.

The stretchable units including the leakage-preventing stretchable unit 43, the leg-surrounding stretchable unit 42, the waist-surrounding stretchable unit 45, and the crotch stretchable unit 41 in the present invention are portions where elastic members such as rubber threads and stretchable sheets are arranged in a stretchable state, and do not include portions where elastic members are arranged in a non-stretchable state. That is, the stretchable portion is an effective length portion of the elastic member constituting the stretchable portion. In other embodiments, the crotch stretch unit 41 may be disposed only on the front side of the center 10LC, not across the center 10LC in the front-rear direction of the disposable diaper, or may be disposed only on the rear side of the center 10 LC.

(3) Absorbent core structure

Next, the structure of the absorbent core 31 will be described in detail with reference to fig. 2. The absorbent core 31 has a narrow portion 35 whose length in the width direction is shorter than the front portion and the rear portion, a front portion located on the front side of the narrow portion 35, and a rear portion located on the rear side of the narrow portion 35. The length in the width direction W of the absorbent core 31 of the narrower portion 35 is shorter than the length in the width direction W of the absorbent core 31 in the front portion and shorter than the length in the width direction W of the absorbent core 31 in the rear portion. The length in the width direction W of the absorbent core 31 in the front portion may be the same as or different from the length in the width direction W of the absorbent core 31 in the rear portion. The narrow portion 35 is disposed between the front and rear portions. The width-directional length of the narrowed portion 35 increases toward the outer side in the front-rear direction L. The top view shape of the absorbent core 31 is an hourglass timer shape. In addition, not only the absorbent core 31 but also the absorbent body including the core-covering sheet may have an hourglass timer shape.

The absorbent core 31 may have a low basis weight portion 33 in which the weight per unit area of the absorbent material is lower than that of the surrounding area. The low area weight portion 33 is provided along the front-rear direction L. The low basis weight portion 33 may extend in the front-rear direction L, may be parallel to the front-rear direction L, or may be inclined at an angle of less than 90 degrees with respect to the front-rear direction L. The low basis weight portion 33 is a portion of the absorbent material having a lower basis weight than the surrounding absorbent core 31, is thinner than the surrounding absorbent core 31, and has lower rigidity than the surrounding absorbent core 31. Thus, the low basis weight portion 33 is likely to be a deformation base point in the worn state. The absorbent core 31 is easy to form a deformation base point extending in the front-rear direction in the worn state. The low basis weight portion 33 may be a portion where the basis weight of the absorbent material is substantially zero (a portion where the basis weight is 0 in design but the surrounding absorbent material is included), or a portion where the absorbent material having a smaller basis weight than the surrounding is disposed. The low basis weight portion 33 may be a slit having a constant length in the width direction W, or may be a notch having a substantially zero length in the width direction W. The length of each low basis weight portion 33 in the width direction W may be 2mm or more and 10mm or less, and more preferably, may be 8mm or more and the thickness of the absorbent core 31. By setting the length of the low basis weight portion 33 in the width direction to be equal to or greater than the thickness of the absorbent core 31, the absorbent core 31 is easily deformed in the thickness direction with the low basis weight portion 33 as a base point. Further, by setting the length of the low basis weight portion 33 in the width direction to 8mm or less, it is possible to suppress the feeling of discomfort in the absorption performance due to the long length of the low basis weight portion in the width direction. The length of the low basis weight portion 33 in the front-rear direction L may be 30mm to 180 mm.

The low basis weight portions 33 are arranged in pairs with a space therebetween in the width direction W. The low basis weight parts 33 may be disposed on both sides of the center 10WC of the disposable diaper in the width direction W with a space therebetween. The center of the low basis weight portion 33 in the front-rear direction may be disposed on the rear side of the center 10LC in the front-rear direction of the disposable diaper. The front end edge 33F of the low basis weight portion 33 may be positioned on the front side of the front end edge 41F of the crotch stretch unit 41, and the rear end edge 33R of the low basis weight portion 33 may be positioned on the rear side of the rear end edge 41R or aligned with the rear end edge 41R of the crotch stretch unit 41. The outer edge of the low basis weight portion 33 may be aligned in the width direction with a rubber thread located on the outer side in the width direction of the rubber threads constituting the crotch stretch unit 41, and the inner edge of the low basis weight portion 33 may be aligned in the width direction with a rubber thread located on the inner side in the width direction of the rubber threads constituting the crotch stretch unit 41.

The absorbent core 31 may have a high rigidity portion 70 having higher rigidity than the surrounding area. The high rigidity portion 70 may include a central high rigidity portion 71 disposed between the pair of crotch stretch units 41, a rear high rigidity portion 72 disposed on the rear side of the crotch stretch units 41, and a front high rigidity portion 73 disposed on the front side of the crotch stretch units 41. The central high rigidity portion 71, the rear high rigidity portion 72, and the front high rigidity portion 73 are separated in the front-rear direction L, respectively. The high rigidity portion 70 is a region having higher bending rigidity than the surrounding region. The high rigidity portion 70 may be a portion having a higher mass per unit area than the surrounding region, or may be a portion obtained by compressing the absorbent core 31 in the thickness direction. The high rigidity portion 70 of the present embodiment is a portion provided with a compressed portion that compresses the absorbent core 31. The compressed portion may be formed by compressing at least the absorbent core 31 in the thickness direction T, or may be formed by compressing the absorbent core 31 and other members such as the core covering sheet 32.

The central high rigidity portion 71 is provided in a region between the pair of low basis weight portions 33. The front end edge 71F of the central high rigidity portion 71 may be positioned in alignment with the front end edge 33F of the low basis weight portion 33 or on the rear side of the front end edge 33F of the low basis weight portion 33. The rear end edge 71R of the central high rigidity portion 71 may be located on the front side of the rear end edge 33R of the low basis weight portion 33. The center of the central high rigidity portion 71 in the front-rear direction may be located forward of the center of the low basis weight portion 33 in the front-rear direction. The central high rigidity portion 71 may be disposed at a distance from the low unit area weight portion 33 in the width direction W. The central high stiffness portion 71 may straddle the center 10LC in the front-back direction of the disposable diaper and the center 10WC in the width direction W of the disposable diaper.

The crotch stretch unit 41 may be located on both sides of the center in the width direction of the central high rigidity portion 71 and extend rearward of the central high rigidity portion 71. The absorbent core 31 may have a 1 st region R41, a 2 nd region R42, and a 3 rd region R43, the 1 st region R41 may have the crotch stretch unit 41 disposed rearward of the central high rigidity unit 71, the 2 nd region R42 may have the central high rigidity unit 71 and the crotch stretch unit 41 overlapped with each other in the thickness direction or the width direction, and the 3 rd region R43 may have the central high rigidity unit 71 disposed forward of the crotch stretch unit 41. The 1 st region R41 and the 2 nd region R42 are adjacent in the front-rear direction L, and the 2 nd region R42 and the 3 rd region R43 are adjacent in the front-rear direction L. The rear end edge of the 1 st region R41 is aligned with the rear end edge 41R of the crotch stretch unit 41, and the front end edge of the 1 st region R41 is aligned with the rear end edge 71R of the central high rigidity portion 71. The rear end edge of the 2 nd region R42 is aligned with the front end edge of the 1 st region R41, and the front end edge of the 2 nd region R42 is aligned with the front end edge 41F of the crotch stretch unit 41. The rear end edge of the 3 rd region R43 is aligned with the front end edge of the 2 nd region R42, and the front end edge of the 3 rd region R43 is aligned with the front end edge 71F of the central high rigidity portion 71.

The rear high rigidity portion 72 may be disposed on the rear side of the low basis weight portion 33. The outer side edge of the rear high rigidity portion 72 may extend outward in the width direction W toward the rear side. The length of the front end edge of the rear high rigidity portion 72 in the width direction W may be longer than the length of the center high rigidity portion 71 in the width direction W. The rear high rigidity portion 72 may cross the center 10WC of the disposable diaper in the width direction W. The front high rigidity portion 73 may be disposed on the front side of the low basis weight portion 33. The front high rigidity portions 73 may be disposed on both sides of the center 10WC of the disposable diaper in the width direction W with a space therebetween. The front end edge of the front high rigidity portion 73 may extend toward the outer side in the width direction W toward the front side.

The absorbent core 31 may have a pair of deformation origin point portions 85 provided at positions rearward of the crotch stretch unit 41. The deformation base point portions 85 extend rearward and outward in the width direction W at a position rearward of the crotch stretch unit 41, and are arranged in a pair with a space therebetween in the width direction W. The deformation origin portions 85 serve as origin points for deformation of the absorbent core 31 in the thickness direction. The deformation base point portion 85 of the present embodiment is constituted by the outer portion 72S of the rear high rigidity portion 72. The deformation base point portion 85 has a base point edge 85E serving as an edge of a deformation base point. The substantial point edge is the edge of the fold line forming the thickness of the absorbent core 31. The base point edge 85E of the present embodiment is the outer edge 72E of the rear high rigidity portion 72. The deformation origin portion 85 of the present embodiment includes a region extending inward in the width direction W from the origin edge 85E by the thickness of the absorbent core 31.

Here, the outer portion in the present invention means a portion that occupies a certain range in the width direction W including an outer edge in the width direction W, and the outer edge means an outer edge in the width direction W. The inner side portion is a portion that occupies a certain range in the width direction W including an inner edge in the width direction W, and the inner side edge is an inner edge in the width direction W. The deformation origin point portion 85 is not limited to the outside portion of the high rigidity portion formed by the compressed portion, as long as it serves as an origin point for deforming the absorbent core 31 in the thickness direction. The deformation base point portion in other embodiments will be described later.

(4) Deformation form of disposable diaper when worn

Next, a deformation mode of the disposable diaper 10 when worn will be described with reference to fig. 6 to 8. Fig. 6 is a view schematically showing a state of wearing the disposable diaper on a-a section. Fig. 7 is a view schematically showing a worn state of the disposable diaper according to the embodiment, and is a view showing a wearer in a lying state viewed from the front side. Fig. 8 is a view for explaining a deformed state of the absorbent core when worn, showing a plane of the absorbent core. In fig. 9, solid lines indicate the absorbent core 31 and the crotch stretch unit 41 before deformation, and two-dot chain lines indicate the absorbent core 31 and the crotch stretch unit 41 after deformation. In fig. 7, for convenience of explanation, only the absorbent core 31, the crotch stretch unit 41, and the waist stretch unit 45 are shown, and the other members are not shown. FIG. 9 is a view for explaining a deformed state of the absorber at the time of wearing the disposable diaper on the B-B section. In addition, a line BL shown in fig. 6 indicates a line of the body of the wearer.

The absorbent core 31 in the crotch region S3 is pulled up toward the body by contraction of the crotch stretch unit 41. The pair of crotch stretch units 41 are positioned on both outer sides of the center in the width direction W, and the region overlapping the crotch stretch unit 41 is pulled up by contraction of the crotch stretch unit 41, and the region sandwiched between the right and left crotch stretch units 41 is pulled up while maintaining a flat shape along the body. The pair of crotch stretch units 41 are positioned inward in the width direction of the outer edge 31E of the absorbent core 31, and the central region R32 between the pair of crotch stretch units 41 is pulled up toward the body side with respect to the side regions R31. Thus, the center of the absorbent core in the width direction can be deformed into a convex shape with the side portions as base points, and fit between the crotch of the body can be secured. When the central region R32 is pulled up toward the body, the narrower portion 35 is pulled inward in the width direction in the region where the narrower portion 35 and the crotch stretch unit 41 overlap in the width direction, and a 1 st folding line FL1 is formed that connects the rear end edge 41R of the crotch stretch unit 41 and the rear end edge 35R of the narrower portion 35. As shown in fig. 2, the 1 st folding line FL1 extends from the rear end edge 41R of the crotch stretch unit 41 to the outer edge 31E of the absorbent core 31 located on both sides in the width direction. In the case where the crotch stretch unit 41 is configured by a plurality of elastic members as in the present embodiment, the 1 st folding line FL1 is easily formed so as to connect the rear end edge of the elastic member located on the outer side in the width direction to the rear end edge 35R of the narrower portion 35. The deformation caused by the pair of crotch stretch units 41 is guided to the outer edge 31E of the absorbent core 31 along the above-described 1 st folding line FL1, and the transmission of the deformation caused by the crotch stretch units 41 to the rear body surrounding region side can be suppressed. The adhesive force to the buttocks can be ensured and the rear leakage can be restrained.

Further, by forming the 1 st folding line FL1, deformation that shortens the distance of the 1 st folding line FL1 is suppressed, and the force that moves the rear end edge 35R of the narrow portion 35 inward in the width direction is opposed. This makes it difficult for the rear end edge 35R of the narrowed portion 35 to move inward in the width direction W, and the width of the absorbent core 31 in the rear body surrounding region S2 can be ensured. This enables the buttocks to be covered with a wide area by the absorbent core, and leakage can be suppressed.

The front end edge 41F of the crotch stretch unit 41 may be disposed rearward of the front end edge 35F of the narrower portion 35. When the central region R32 is pulled up toward the wearer side with respect to the side regions R31 and the absorbent core 31 is deformed into a convex shape, the 2 nd folding line FL2 connecting the front end edge 41F of the crotch stretch unit 41 and the front end edge 35F of the narrower portion 35 is also formed. As shown in fig. 2, the 2 nd folding line FL2 also reaches the outer edges 31E of the absorbent core 31 on both sides in the width direction from the front end edge 41F of the crotch stretch unit 41. In the case where the crotch stretch unit 41 is configured by a plurality of elastic members as in the present embodiment, the 2 nd folding line FL2 is easily formed so as to connect the front end edge of the elastic member located on the outer side in the width direction to the front end edge 35F of the narrower portion 35. It is possible to suppress the transmission of the deformation caused by the crotch stretch unit 41 to the front body surrounding region S1 side. The adhesive property to the abdomen can be ensured, and front leakage can be suppressed. The 2 nd folding line FL2 can ensure the width of the absorbent core 31 in the front body surrounding region S1 against the force that moves the front end edge 35F of the narrow portion 35 inward in the width direction W. This enables the abdomen to be covered with a wide area by the absorbent core 31, and leakage can be further suppressed.

The distance W11 between the crotch stretch unit 41 and the outer edge 31E of the absorbent core 31 may be 1/4 or more of the length W12 between the outer edges 31E of the absorbent core 31. The outer edge 31E of the absorbent core 31 here refers to an outer edge in a region extending in the width direction W from the crotch stretch unit 41. That is, it is sufficient that W11 × 4> W12 is satisfied on an arbitrary straight line passing through the crotch stretch unit 41 and extending in the width direction W. When the crotch stretch unit 41 is deformed to a convex shape toward the body side as a base point, a region on the outer side in the width direction W than the crotch stretch unit 41 becomes a region for supporting the convex deformation. Since the side region R31 on the outer side in the width direction W than the crotch stretch unit 41 is equal to or more than 1/4 of the entire region in the width direction of the absorbent core 31, the convex deformation is stably supported, and the convex shape is easily maintained. Further, the rigidity of the region outside the crotch stretch unit 41 in the width direction is increased, so that the narrowed portion 35 of the absorbent core 31 is not excessively deformed into a convex shape, and the area of the body covered with the absorbent core 31 can be ensured. Leakage is more suppressed by covering the body with a wide area by the absorbent core.

As shown in fig. 3, in the extended state of the disposable diaper, the distance W21 in the width direction between the apex of the contracted portion 61 and the base point portion 62 may be longer than the distance W22 in the width direction between the outer edge of the absorbent core 31 and the crotch stretch unit 41 at the narrower portion 35. Here, the apex of the contracted portion 61 is the inner edge of the side sheet 22. In the configuration in which the length of the narrower portion 35 in the width direction changes, W21> W22 may be satisfied on any straight line passing through the narrower portion 35 and the crotch stretch unit 41 and extending in the width direction W. The leakage preventing gathers 60 rise toward the wearer side with the contracted portion 61 as a vertex due to contraction of the leakage preventing stretchable and contractible portion 43. The maximum height of the standing portion of the leakage preventing wrinkle 60 at the time of standing is a distance W21 in the width direction between the apex of the constricted portion 61 and the base point portion 62. The maximum height of the convex deformation in the region where the narrowed portion 35 is provided is the distance W22 between the outer edge of the narrowed portion 35 and the crotch stretch unit 41. Since the distance W21 is longer than the distance W22, the height of the leakage preventing wrinkles 60 is higher than the height of the convex deformation, and side leakage can be suppressed by the leakage preventing wrinkles 60.

The distance between the elastic members of the 1 st crotch stretch unit 411 and the distance between the elastic members of the 2 nd crotch stretch unit 412 may be 3 times or less the thickness of the absorbent core. Here, the thickness of the absorbent core 31 is the maximum thickness of the absorbent core. The distance between the elastic members of the 1 st crotch stretch unit 411 and the distance between the elastic members of the 2 nd crotch stretch unit 412 are, in the present embodiment, the distances between the two rubber threads. By providing the 1 st crotch stretch unit 411 and the 2 nd crotch stretch unit 412 with a plurality of elastic members, respectively, the force for pulling up the absorbent core is increased, and the convex shape of the absorbent core is more easily maintained. When the distance between the elastic members of the 1 st crotch stretch unit 411 and the distance between the elastic members of the 2 nd crotch stretch unit 412 are longer than 3 times the thickness of the absorbent core, the respective elastic members may pull up the absorbent core independently, and the elastic members may not pull up the absorbent core integrally. Since the distance between the elastic members is 3 times or less the thickness of the absorbent core 31, the plurality of elastic members of the 1 st crotch stretch unit 411 can be integrated to pull up the absorbent core, and the plurality of elastic members of the 2 nd crotch stretch unit 412 can be integrated to pull up the absorbent core. This makes it easier to form the convex shape of the absorbent core 31.

The absorbent core 31 in the crotch region S3 may be provided with a high rigidity portion having higher rigidity than the surrounding region between the pair of crotch stretch units 41. The high rigidity portion may cross the center in the width direction of the absorbent core 31. The high rigidity portion can increase the rigidity, and the absorbent core can easily have a planar shape along the body. The region between the pair of crotch stretch units 41 is not excessively deformed into a convex shape, and the area of the body covered with the absorbent core 31 can be ensured. Further, since the high rigidity portion is provided across the center of the absorbent core 31 in the width direction, the absorbent core can be arranged along the excretory opening of the body, so that the body fluid intake performance can be improved and leakage can be suppressed. The high rigidity portion may be the central high rigidity portion 71 or may be a lattice pressing portion, not shown, arranged in a lattice shape. The lattice squeezing portions may be formed by compressing the absorbent core at least in the thickness direction, and may be formed not only in the region between the pair of crotch stretch units 41 but also over the entire surface of the absorbent core.

The waist stretchable unit 45 may be disposed in a region R11 overlapping the absorbent core 31 on the rear side of the narrower portion 35 and on the outer side in the width direction W of the crotch stretchable unit 41. As described above, the 1 st folding line FL1 extending from the rear end edge 41R of the crotch stretch unit 41 reaches the rear end edge 35R of the narrowed portion 35. The 1 st folding line FL1 opposes the force that moves the rear end edge 35R of the narrow portion 35 inward in the width direction W, and the rear end edge 35R of the narrow portion 35 is less likely to move inward in the width direction W. As shown in fig. 8, the length of the absorbent core 31 in the width direction W in the region overlapping the waist elastics 45 is shortened by contraction of the waist elastics 45. At this time, the region R11 located rearward of the narrower portion 35 and outward in the width direction of the crotch stretch unit 41 is easily deformed inward in the width direction W from the rear end edge 35R of the narrower portion 35 by contraction of the waist stretch unit 45. At this time, the rear end edge 35R of the narrowed portion 35 serves as a deformation base point and is less likely to move inward in the width direction W. The rear end edge 35R of the narrower section 35 located on the rear side of the crotch stretch unit 41 is less likely to move inward in the width direction W, and the length of the absorbent core 31 in the width direction W in the rear body surrounding region S2 is more likely to be secured, and rearward leakage can be suppressed.

As shown in fig. 8, the waist stretchable unit 45 may have a 1 st region 451 and a 2 nd region 452 having a higher elongation in the width direction than the 1 st region 451, and the 1 st region 451 may be disposed on a 1 st extension line EL1 extending rearward from the rear end edge 41R of the crotch stretchable unit 41. The 2 nd region 452 is provided in a region extending across the center in the width direction of the disposable diaper and outside the waist stretching portion 45. The 1 st region 451 is sandwiched by the 2 nd region 452. The 1 st region 451 and the 2 nd region 452 of the waist elastics 45 have different elongations in the width direction. The 1 st zone 451 has a lower elongation and is less likely to contract than the 2 nd zone 452. Since the 1 st extension line EL1 is provided with the 1 st region 451, the region deformed in a convex shape by contraction of the crotch stretch unit 41 is less likely to be shrunk in the width direction by contraction of the waist stretch unit 45, and the convex deformed state is more likely to be maintained. In the embodiment where a plurality of elastic members constituting the crotch stretch unit 41 are provided, the 1 st region 451 may be arranged on the 1 st extension line EL1 of at least one of the elastic members.

The elongation of the waist stretchable panel 45 can be adjusted by varying the elongation at the time of manufacture or by varying the number of elastic members arranged. In the aspect in which the waist stretching unit 45 is stretched by the gear in the width direction W, the gear stretching in the region where the elongation is low (for example, the 1 st region 451) is reduced when the gear is used for stretching. The gear elongation in the region where the elongation is high (e.g., region 2 452) is enhanced. The strength of the gear stretching can be adjusted by changing the depth of the convex parts of the gear, the distance between the convex parts of the gear and the number of times of gear stretching. The elongation of the strongly stretched region becomes relatively high, and the elongation of the weakly stretched region becomes relatively low.

The 2 nd region 452 may be disposed on a 2 nd extension line EL2 extending rearward from a region (side region R31 shown in fig. 8) located outward in the width direction of the crotch stretch unit 41. The 2 nd extension line EL2 is a line extending rearward from the side region R31, and is provided in plural at different positions in the width direction. The 2 nd region 452 may be disposed on any 2 nd extension line EL 2. In the region on the outer side in the width direction than the crotch stretch unit, the absorbent core 31 is more likely to deform inward in the width direction with the rear end edge 35R of the narrower portion 35 as a starting point. The rear end edge 35R of the narrower section 35 located on the rear side of the crotch stretch unit 41 is less likely to move inward in the width direction W, and the length of the absorbent core 31 in the width direction W in the rear body surrounding region S2 is more likely to be secured, and rearward leakage can be suppressed.

The leg hole stretch units 42 may be arranged on the 1 st imaginary line VL1 connecting the front end edge of the inner side edge of the coupling unit 93 of the fastening band 91 and the rear end edge 41R of the crotch stretch unit 41. When the tape-type disposable diaper 10 is to be put on, the rear body area S2 of the disposable diaper 10 is first placed on the hips of the wearer in a state where the disposable diaper 10 is unfolded. Then, the disposable diaper 10 is passed between the legs of the wearer, and the body is covered with the crotch region by pulling the diaper toward the crotch region side. Then, the joint 93 of the fastening tape 91 is fixed to the front leg region S1. As shown in fig. 1, when the fastening tape 91 is pulled, a force pulling outward in the width direction acts along the 1 st virtual line VL1 connecting the front end edge at the inner edge of the coupling portion 93 and the rear end edge of the crotch stretch panel when the fastening tape is pulled. The rear end edge 41R of the crotch stretch unit 41 is pulled outward in the width direction W by the operation during wearing, and the absorbent core 31 deformed to be convex toward the body side is also pulled outward in the width direction by the crotch stretch unit 41. This suppresses the absorbent core 31 from being deformed convexly inward in the width direction, and the absorbent core is easily maintained in a deformed state convexly toward the body side. Further, the leg hole stretch units 42 are disposed on the 1 st imaginary line VL1, and the leg hole stretch units 42 can be pulled up even when the wearer wears the garment. This improves the fit to the crotch excretory opening and the fit to the leg band, and further suppresses leakage.

A pair of deformation origin point portions 85 may be provided on the absorbent core 31 on the rear side of the crotch stretch unit 41. When the disposable diaper 10 is put on, the disposable diaper 10 is passed between the legs of the wearer, and when the diaper is pulled toward the crotch region, the absorbent core 31 is easily deformed with the deformation origin portions 85 as origin points. The deformation origin point portion 85 is provided on the rear side of the crotch stretch unit 41 located in the crotch region, and the deformation origin point of the absorbent core 31 is formed on the rear side of the crotch stretch unit 41. The deformation origin point portion 85 extends rearward and outward in the width direction W, and the absorbent core 31 is formed with deformation origin points extending inward in the width direction W from the rear body surrounding region toward the crotch region. Thus, when the rear body region is placed on the buttocks and the diaper is pulled toward the crotch region, the absorber is deformed by the base point extending inward in the width direction W from the rear body region toward the crotch region. Specifically, as shown in fig. 9, the absorbent body in the region where the deformation origin portions 85 are provided is deformed with the outer edge 72E of the high stiffness portion 72 (the origin edge 85E of the deformation origin portions 85) as the origin, and the region inside in the width direction W with respect to the outer edge 72E is disposed on the skin surface side with respect to the region outside in the width direction W with respect to the outer edge 72E. The reason why the region on the inner side in the width direction W than the outer edge 72E is arranged on the skin surface side than the region on the outer side in the width direction W than the outer edge 72E is: the center in the width direction W of the absorbent core 31 is pulled up toward the body side by contraction of the crotch stretch unit 41, and a force is normally applied to the center in the width direction W of the absorbent core 31 when the wearer pulls the diaper; and the center of the absorbent core 31 in the width direction W is pulled up in a state where the outer side portion of the absorbent article (for example, the vicinity of the leg hole openings) is fitted over the legs at the time of wearing. The absorbent core 31 deforms toward the crotch region side so that the length in the width direction W becomes shorter by deforming from the deformation origin point portions 85 as origin points. As shown in fig. 6 and 7, the absorbent core 31 located at the front side of the deformation base point portions 85 deforms to a convex shape toward the body side due to contraction of the pair of crotch stretch units 41, and the central region R32 stands up with respect to the side regions R31. Thus, the absorbent core 31 in the crotch region is arranged along the body side, and the absorbent core 31 can be appropriately accommodated in the crotch of the wearer. The absorbent core 31 can be covered over a wide area with respect to the buttocks of the wearer, and the absorbent core 31 can be compactly stored in the gap between the legs of the wearer. By disposing the disposable diaper at an appropriate position between the wearer's thighs, the front waistline region can be pulled up to a position covering the abdomen of the wearer. In a tape-type disposable diaper, the body of a wearer can be appropriately covered, and leakage can be suppressed.

As shown in fig. 1, the deformation base point portion 85 may be disposed on the inner side in the width direction than a 2 nd virtual line VL2, which connects the rear end edge 41R of the crotch stretch unit 41 and the rear end edge 35R of the narrower portion 35, with the 2 nd virtual line VL 2. The 2 nd virtual line VL2 connecting the rear end edge of the crotch stretch unit and the rear end edge of the narrow portion is a line forming the 1 st folding line FL1, and is a line opposing the force moving the rear end edge 35R of the narrow portion 35 inward in the width direction. The region sandwiched by the 1 st folding line FL1 is arranged so as to cover the body. The absorbent core 31 is deformed by the deformation origin point portions 85 at a position on the rear side of the crotch stretch unit 41 in the region sandwiched by the 1 st folding line FL 1. The deformation origin portions 85 extend rearward and outward in the width direction, and the absorbent core 31 is formed with deformation origin points extending inward in the width direction from the rear body surrounding region S2 toward the crotch region S3, and the absorbent core 31 deforms toward the crotch region side so that the length in the width direction W becomes shorter. The absorbent core is conformable from the wearer's hips to the crotch region, and is more resistant to leakage.

The angle α of the 2 nd imaginary line VL2 with respect to the width direction may be smaller than the angle β of the deformation base point portion 85 with respect to the width direction. Since the angle α of the 2 nd virtual line VL2 with respect to the width direction is small, the movement of the rear end edge 35R of the narrower portion 35 to the inside in the width direction can be further suppressed, and the width of the absorbent core 31 in the rear body surrounding region S2 can be further secured. Further, since the angle β of the deformation origin point portion 85 with respect to the width direction is relatively large, the region sandwiched by the 2 nd virtual line VL2 can be locally deformed, and the body can be covered with the region outside the deformation origin point portion 85 in the width direction. Thus, the absorbent core can cover the buttocks with a wide area, and can suppress leakage.

The outer edge of the crotch stretch unit 41 may be disposed outward in the width direction W from the outer edge of the deformation origin point unit 85. However, it is more preferable that the outer edge of the crotch stretch unit 41 be disposed inward in the width direction W from the outer edge of the deformation origin point unit 85. With such a configuration, the deformation of the absorbent core 31 with the deformation origin point portions 85 as origin points and the deformation of the absorbent core 31 due to the crotch stretch unit 41 are more easily interlocked. This makes it easier to dispose the absorbent core 31, which has been deformed so that the length in the width direction W from the back body surrounding region toward the crotch region side is shorter, closer to the body side in the crotch region. The outer edge of the crotch stretch unit 41 is the outer edge of the elastic member located outermost in the width direction W, of the elastic members constituting the crotch stretch unit 41. The rubber thread constituting the crotch stretch unit 41 of the present embodiment is arranged in the front-rear direction, and the elastic member positioned outside in the width direction W constitutes the outer edge of the crotch stretch unit 41.

The deformation base point portions 85 and the crotch stretch unit 41 may be shifted in the width direction W. However, it is more preferable that at least a part of the deformation base point portion 85 is disposed on the 1 st extension line EL1 extending rearward from the rear end edge of the crotch stretch unit 41. The deformation of the absorbent core 31 with the deformation origin point portions 85 as origin points is more likely to be interlocked with the deformation of the absorbent core 31 caused by the crotch stretch unit 41. This makes it easier to dispose the absorbent core 31, which has been deformed so that the length in the width direction W from the back body surrounding region toward the crotch region side is shorter, closer to the body side in the crotch region. In the embodiment where a plurality of elastic members constituting the crotch stretch unit 41 are provided, the deformation base point units 85 may be arranged on the 1 st extension line EL1 of at least one of the elastic members.

The deformation base point portion 85 may cross a 1 st intermediate line ML1 along the front-rear direction L, the 1 st intermediate line ML1 being located between the front-rear direction center 10LC of the disposable diaper and the front end edge of the joint portion 93 in the front-rear direction L. As shown in fig. 1, the 1 st intermediate line ML1 is a line that passes through the center 10LC in the front-rear direction of the disposable diaper and the center in the front-rear direction of the front end edge of the joint 93 and extends in the width direction W. The position more posterior than the 1 st middle line ML1 is generally the area that bears the buttocks when worn. The deformation base point 85 is arranged from an area where the buttocks of the wearer are supported to an area where the buttocks are not supported, across the 1 st intermediate line ML1 in the front-rear direction. When the absorbent core 31 is worn, the region not bearing the buttocks is pulled forward in a state where the region on the rear side of the 1 st intermediate line ML1 is pressed by the buttocks, and the absorbent core is more easily deformed with the deformation origin point portion 85 as the origin point. This allows the absorbent core 31 to be deformed so that the width of the absorbent core 31 becomes shorter, and the disposable diaper can be placed at an appropriate position between the wearer's thighs to properly cover the body of the wearer.

The rear end edge 41R of the crotch stretch unit 41 may be disposed on the front side of the 1 st intermediate line ML 1. The rear end edge 41R of the crotch stretch unit 41 is disposed in a region not supporting the hip of the wearer. When the wearer wears the garment, the crotch stretch unit 41 is more easily stretched by pulling the region not bearing the buttocks forward in a state where the region on the rear side of the 1 st intermediate line ML1 is pressed by the buttocks. This makes it easier to pull up the region where the crotch stretch unit 41 is disposed with respect to the body, and the absorbent core 31 can be further appropriately accommodated between the wearer's thighs. In the modification, the rear end edge 41R of the crotch stretch unit 41 may be located rearward of the 1 st intermediate line ML 1. When the wearer wears the garment, the front end edge 41F side of the crotch stretch unit 41 is pulled forward in a state where the rear end edge 41R of the crotch stretch unit 41 is pressed against the buttocks, and the crotch stretch unit 41 is more easily extended. This allows the region in which the crotch stretch unit 41 is disposed to be pulled up with respect to the body, and the absorbent core can be further appropriately accommodated in the crotch of the wearer.

The front end edge of the deformation base point portion 85 may be disposed on the front side of the 2 nd intermediate line ML2, and the 2 nd intermediate line ML2 may be located between the rear end edge of the deformation base point portion 85 and the rear end edge of the crotch stretch unit 41 in the front-rear direction. As shown in fig. 1, the 2 nd intermediate line ML2 is a line that passes through the middle between the rear end edge of the deformation base point portion 85 and the rear end edge 41R of the crotch stretch unit 41 in the front-rear direction and extends in the width direction W. The deformation origin point portions 85 are provided in a region of at least half of the region between the rear end edge of the deformation origin point portion 85 and the rear end edge of the crotch stretch unit 41. This makes it easier for the deformation of the absorbent core 31 with the deformation origin point portions 85 as origin points to be interlocked with the deformation of the absorbent core 31 caused by the crotch stretch unit 41. This makes it easy to deform the absorbent core 31 from the rear body surrounding region S2 to the crotch region S3 into a shape conforming to the body, and enables the absorbent core 31 to be compactly arranged in the crotch region while covering the buttocks. The disposable diaper can be arranged at an appropriate position between the wearer's thighs and can appropriately cover the body of the wearer.

A high rigidity portion having higher rigidity than that of a region on the outer side in the width direction W than the deformation base point portions 85 may be provided between the pair of deformation base point portions 85. In the present embodiment, the outer side portions of the rear high rigidity portion constitute deformation base point portions 85, and the region between the outer side portions of the rear high rigidity portion constitutes the high rigidity portion of the present structure. By providing the high rigidity portion between the deformation base point portions 85, a difference in rigidity occurs between the region outside the deformation base point portions 85 in the width direction W and the region inside the deformation base point portions 85, and the absorbent core 31 is more easily deformed with the deformation base point portions 85 as base points. This makes it easier for the absorbent core 31 to deform toward the crotch region side so that the length in the width direction W becomes shorter, and makes it easier to accommodate the absorbent core 31 between the wearer's thighs. By disposing the disposable diaper at an appropriate position between the wearer's thighs, the body of the wearer can be appropriately covered. In addition, in the deformation base point portion having relatively low rigidity (for example, the deformation base point portion composed of a low basis weight portion), the rigidity of the high rigidity portion between the pair of deformation base point portions 85 may be higher than the rigidity of the deformation base point portion.

The high rigidity portion between the pair of deformation base point portions 85 may be adjacent to the deformation base point portions 85 in the width direction W. The region on the outer side in the width direction W than the deformation origin portions 85 is easily deformed with respect to the region between the deformation origin portions 85, and the difference in rigidity makes the absorbent core 31 more easily deformed. The pair of deformation base point portions 85 are integrated by a high rigidity portion. The deformation base point portions 85 are integrated with the high rigidity portion and easily deform in a convex shape toward the wearer side, and the absorbent core 31 is more easily accommodated in the crotch of the wearer.

The deformation base point portion 85 and the high rigidity portion between the deformation base point portions 85 in the present embodiment are both constituted by the rear high rigidity portion constituted by the extruded portion. Thus, the deformation base point portion 85 and the high rigidity portion can be formed integrally, and the boundary between the deformation base point portion 85 and the high rigidity portion may not be formed. The rear high rigidity portion as a whole can function as the deformation base point portion 85 and as the high rigidity portion. Further, the deformation base point portion 85 formed by the pressing portion has high rigidity, and the deformation of the absorbent core 31 is more easily stabilized.

The pair of deformation base point units 85 are disposed so as to sandwich the center of the disposable diaper in the width direction W, and at least a part of the deformation base point units 85 may be disposed at a position outside the 3 rd intermediate line ML3 in the width direction W, the 3 rd intermediate line ML3 being located between the center of the absorbent core 31 in the width direction W and the maximum width of the absorbent core 31. As shown in fig. 1, the 3 rd intermediate line ML3 is a line that passes through the center in the width direction W of the absorbent core 31 and the center of the maximum width of the absorbent core 31 and extends in the front-rear direction. In the region of the absorbent core 31 that is half or more in the width direction W, the absorbent core 31 is easily deformed with the deformation origin point portions 85 as origin points. The absorbent core 31 is easily deformed so that the length in the width direction W becomes shorter toward the crotch region in a wide range of the absorbent core 31, and the absorbent core 31 is more easily accommodated in the crotch of the wearer.

The leg hole expansion and contraction portion 42 may be disposed on the 3 rd extension line EL3 extending outward in the width direction W from the deformation base point portion 85. The 3 rd extension line EL3 is a line extending outward in the width direction W from an arbitrary position of the deformation base point portion 85, and a plurality of lines are provided at positions different in the front-rear direction. At least a part of the leg hole expansion/contraction part 42 may be disposed on any of the 3 rd extension lines EL 3. When the diaper is pulled toward the crotch region side with the rear body area bearing the buttocks, the rear body area is pressed by the buttocks and the region outside the absorbent core 31 in the width direction W is in close contact with the legs. Since the absorbent core 31 is deformed in a state where the leg hole stretch units and the buttocks are fitted to the body, the central region R32 is easily raised with respect to the side regions R31 at a position forward of the buttocks, and the absorbent core 31 is more easily deformed with the deformation origin point units 85 as origin points.

The leg hole stretch units 42 may be disposed on an extension line extending outward in the width direction W from the crotch stretch unit 41. The absorbent core 31 is deformed in a state where the leg hole stretch units are fitted to the body, and the central region R32 is more likely to stand up relative to the side regions R31. The absorbent core 31 is more easily pulled up toward the wearer side by the contraction of the crotch stretch unit 41. The leg hole stretch units 42 may extend rearward and outward in the width direction W. The leg hole stretch units extending toward the rear side and toward the outer side in the width direction W are in close contact with the body, and the hips of the wearer can be covered with the disposable diaper. The absorbent core 31 can be deformed so that the length in the width direction W of the absorbent core 31 becomes shorter toward the crotch region in a state where the absorbent core covers the buttocks in a wide range toward the rear side. The absorbent core 31 can be appropriately accommodated in the crotch of the wearer, and the entire body can be covered with the disposable diaper, and leakage can be suppressed.

The absorbent core 31 may have a flap portion 27 extending rearward and outward in the width direction W at a position outward in the width direction W, and the flap portion 27 may be disposed on the 2 nd extension line EL 2. The flap portion 27 extends rearward and outward in the width direction W at the outer portion of the disposable diaper, and is indicated by hatching in fig. 1. When the rear body area is placed over the buttocks and the diaper is pulled toward the crotch area, the rear body area is pressed against the buttocks and the side flap portions on the outer side in the width direction W than the absorbent core 31 easily come into contact with the legs. Thus, the absorbent core 31 is deformed in a state where the side flap portions positioned on the outer sides in the width direction W and the regions for supporting the buttocks are pressed, and is more easily deformed with the deformation origin portions 85 as origin points.

The low basis weight portion 33 may be disposed in a region overlapping the crotch stretch unit 41. The absorbent core 31 deforms when worn, with a low basis weight portion extending in the front-rear direction as a base point. This makes it easier to deform the absorbent core 31 into a convex shape toward the body side by contraction of the crotch stretch unit 41, and the absorbent core 31 can be appropriately accommodated in the crotch of the wearer. The low basis weight portion 33 serving as a deformation base point of the absorbent core 31 has a lower basis weight than that of the surrounding region, and can maintain a deformed state while suppressing the thickness even after absorption of body fluid.

The measurement of "weight per unit area of absorbent core" in the present specification was performed by the following measurement method. When the disposable diaper 10 is sealed in a package or the like, a sample is taken out from the package and left in this state for 12 hours in an environment of 20 ℃. + -. 2 ℃ and a relative humidity of 60%. + -. 5% RH. In the case of a disposable diaper packaged with a packaging sheet or the like, the packaging sheet is opened and the folded disposable diaper is unfolded. Next, a portion for measuring the basis weight is cut out from the disposable diaper, and a portion other than the absorbent core such as a topsheet is removed from the cut-out portion. Then, the area and weight of the portion for measuring the weight per unit area of the absorbent core were measured. The weight per unit area was calculated based on the weight and the area.

The "flexural rigidity" in the present specification may be a value measured from gurley stiffness. The measurement of the Gurley stiffness can be carried out in accordance with JIS-L1096 using a Gurley softness tester No311 manufactured by Antian Seiki machine (manufactured by Kabushiki Kaisha). The length of the sample in the width direction W for the measurement of gurley stiffness can be set to 30mm, and the length in the front-rear direction can be set to 25 mm.

The "elongation" in the present specification means the degree of elongation, and is measured by the following measurement method. First, when a disposable diaper is enclosed in a package or the like, the disposable diaper is taken out from the package. Second, an arrangement region such as a stretchable sheet constituting the waist stretchable section is cut out, and a sample to be measured is prepared. The sample was left at 20 ℃. + -. 2 ℃ and a relative humidity of 60%. + -. 5% RH for 24 hours, and set as "natural state".

Thirdly, in this natural state, dots (symbols) are intermittently marked in the width direction W at intermediate positions in the front-rear direction L between the end portion (front end portion) on the absorbent core side of the waist stretchable panel and the end portion (rear end portion) on the waist opening side of the waist stretchable panel. In this regard, points (symbols) are marked from the center of the waist stretchable panel in the width direction W to the ends of the sample of the waist stretchable panel in the width direction W at intervals of 5mm from the reference on the left and right sides of the width direction W. Fourth, the distance between points adjacent to each other is measured. This distance is a natural length (5 mm since the marks are provided at intervals of 5 mm). Fifth, the distance between the marks before the stretch from the natural state to the state where the wrinkles formed in the elastic member cannot be visually recognized in the stretchable sheet is measured. Sixth, the elongation is calculated by using a formula of (elongation of each region) — the (distance between symbols in an elongated state)/(distance between symbols in a natural state).

The present invention has been described in detail with reference to the above embodiments, but it is clear to those skilled in the art that the present invention is not limited to the embodiments described in the present specification. The present invention can be implemented as modifications and variations without departing from the spirit and scope of the present invention defined by the claims. Therefore, the description in the present specification is for the purpose of illustration and description, and does not have any restrictive meaning to the present invention.

In addition, the entire contents of japanese patent application No. 2018-152781, filed on 14/8/2018, are incorporated by reference in this specification.

Industrial applicability

The present invention can provide a disposable diaper which can ensure fit between the crotch of the body and also fit between the hip of the wearer, and can suppress leakage.

Description of the reference numerals

10. A disposable diaper; 10LC, center in the front-rear direction of the diaper; 10WC, center of the diaper in the width direction; 21. a dough sheet; 22. a side sheet; 23. a back sheet; 24. an outer sheet; 27. a flank portion; 30. an absorbent body; 31. an absorbent core; 32. a chip-in-chip; 33. a low unit area weight portion; 41. a crotch stretch unit; 42. a leg-surrounding expansion part; 43. a leakage-proof expansion part; 45. a waist-stretching portion; 51. a presentation unit; 71. a central high rigidity portion; 72. a rear high stiffness portion; 81. a decorative part; 85. a deformation base point portion; 91. a fastening tape; 92. a base; 93. a bonding section; 95. a target portion; EL1, extension line 1; EL2, extension line 2; VL1, phantom line 1; VL2, phantom line 2; ML1, 1 st intermediate line; ML2, middle line 2; ML3, 3 rd middle line; s1, a front surrounding area; s2, a posterior body surrounding area; s3, a crotch region; l, the front-back direction; t, the thickness direction; t1, skin surface side; t2, non-skin face side; w, width direction.

Claims

1. A disposable diaper comprising:

a front-back direction and a width direction orthogonal to each other;

a front torso-surrounding region, a rear torso-surrounding region, and a crotch region disposed between the front torso-surrounding region and the rear torso-surrounding region;

an absorbent core disposed in at least the crotch region; and

a pair of crotch stretch units disposed on both outer sides of the center in the width direction of the absorbent core and extending in the front-rear direction,

the absorbent core has a narrow portion whose length in the width direction is shorter than the front portion and the rear portion,

wherein,

at least a part of the crotch stretch unit is disposed at the narrowed portion on the inner side in the width direction than the outer edge of the absorbent core,

the rear end edge of the crotch stretch unit is disposed on the front side of the rear end edge of the narrow portion.

2. The disposable diaper according to claim 1,

the front end edge of the crotch stretch unit is disposed rearward of the front end edge of the narrow portion.

3. The disposable diaper according to claim 1 or 2,

the distance between the crotch stretch unit and the outer edge of the absorbent core is not less than 1/4 of the length between the outer edges of the absorbent core.

4. The disposable diaper according to any one of claims 1 to 3,

the disposable diaper has a pair of side sheets arranged on the skin surface side of the absorbent core and covering the outer side of the absorbent core,

the side sheet forms a pair of leakage-preventing gathers having a contracted portion that rises due to contraction of the leakage-preventing elastic member and a base point portion that serves as a rising fulcrum of the contracted portion at a position outside the contracted portion in the width direction,

the distance in the width direction between the apex of the contracted portion and the base point portion is longer than the distance in the width direction between the outer edge of the absorbent core and the crotch stretch unit at the narrow portion.

5. The disposable diaper according to any one of claims 1 to 4,

the crotch stretch unit has a 1 st crotch stretch unit disposed on one side with respect to the center of the absorbent core in the width direction and a 2 nd crotch stretch unit disposed on the other side with respect to the center of the absorbent core in the width direction,

the 1 st crotch stretch unit and the 2 nd crotch stretch unit each have a plurality of elastic members arranged at intervals in the width direction,

the distance between the elastic members of the 1 st crotch stretch unit and the distance between the elastic members of the 2 nd crotch stretch unit are 3 times or less the thickness of the absorbent core.

6. The disposable diaper according to any one of claims 1 to 5,

the absorbent core in the crotch region is provided with a high rigidity portion having higher rigidity than the surrounding region between the pair of crotch stretch units,

the high rigidity portion crosses the center of the width direction of the absorbent core.

7. The disposable diaper according to any one of claims 1 to 6,

a waist stretchable portion which is stretchable at least in the width direction is provided in the rear body region,

the waist stretchable unit is disposed in a region overlapping the absorbent core at a position rearward of the narrow portion and outward of the crotch stretchable unit in the width direction.

8. The disposable diaper according to claim 7,

the waist stretchable panel has a 1 st region and a 2 nd region having a higher elongation in the width direction than the 1 st region,

the 1 st region is disposed on a 1 st extension line extending rearward from the rear end edge of the crotch stretch unit.

9. The disposable diaper according to claim 8,

the 2 nd region is disposed on a 2 nd extension line extending rearward from a region on the outer side in the width direction than the crotch stretch unit.

10. The disposable diaper according to any one of claims 1 to 9,

the disposable diaper comprises a fastening tape and a leg-surrounding stretchable part,

the fastening tape is disposed in the rear body surrounding region and has a coupling portion coupled to the front body surrounding region,

the leg hole stretch units stretch in the front-rear direction at positions outside the absorbent core in the width direction,

the leg hole stretch units are arranged on a 1 st imaginary line connecting a front end edge at an inner edge of the joint unit and a rear end edge of the crotch stretch unit.

11. The disposable diaper according to any one of claims 1 to 10,

the disposable diaper comprises a fastening tape disposed in the back torso surrounding region and having a joint part joined to the front torso surrounding region,

a pair of deformation base point portions extending outward in the width direction toward the rear side and arranged at a spacing in the width direction are provided on the absorbent core on the rear side of the crotch stretch unit,

the deformation base point portion is disposed at a position inward in the width direction with respect to a 2 nd imaginary line, the 2 nd imaginary line connecting a rear end edge of the crotch stretch portion and a rear end edge of the narrow portion.

12. The disposable diaper according to claim 11,

an angle of the 2 nd imaginary line with respect to the width direction is smaller than an angle of the deformation base point with respect to the width direction.