JP2023000355A5 - - Google Patents

Description

The present invention relates to a pants-type disposable wearable article with improved feel (softness, cushioning) at the end of the waist opening.

Pants-type disposable wearing articles generally include an outer body that forms at least the waist area of the front and back body, and an inner body that is attached to the outer body so as to extend from the front body to the back body, and both sides of the outer body of the front body and both sides of the outer body of the back body are joined to form side seals, forming a waist opening and a pair of leg openings (e.g., Patent Documents 1 and 2).

In typical pants-type disposable wearable articles, the area including the waist part of the outer body has a laminated structure with an elastic member interposed between multiple sheet layers to ensure a good fit to the body.

For pants-type disposable wearable articles, the texture (feel, feel, and feel) of the edge of the waist opening when holding the product in the hand when putting it on or purchasing it, or while wearing it, is extremely important.

For this reason, the exterior body described in Patent Document 1 is proposed to have an outer portion in which the first and second sheets are laminated from the lower waist portion to the waist portion, and an inner portion in which the first and second sheets continuing from this outer portion are folded inward at the edge of the waist opening, with at least one of the sheets extending over the entire waist portion, and the portion of one sheet exposed to the outside that runs from the outer portion through the edge of the waist opening to the inner portion is proposed to be a free portion that is not fixed to the other sheet. The presence of such a free portion improves the flexibility and cushioning of the waist portion, resulting in a good texture.

However, if such loose parts exist, when the first and second sheets are folded back to form the edge of the waist opening, the first and second sheets may shift, resulting in unnecessary rolling up or wrinkles. Also, when the product is worn, the first and second sheets may shift, resulting in a poor fit around the waist.

JP 2016-067436 A International Publication No. 2018/154684

Therefore, the main objective of the present invention is to prevent the sheet from shifting while improving the texture of the waist opening and its surrounding areas.

Representative aspects for solving the above problems are as follows.
<First aspect>
The garment comprises an annular waist region formed by joining both sides of a front body and both sides of a rear body, a middle region extending from the waist region of the front body through a crotch region to the waist region of the rear body, a waist opening provided on the side of the waist region opposite to the middle region, leg openings provided on both sides of the middle region in the width direction, an exterior body forming at least the waist region, and an interior body attached to the exterior body so as to extend from the front body to the rear body,
The exterior body has a waist portion defined as an end portion on the waist opening side,
the waist portion has an outer portion in which a first sheet made of nonwoven fabric and a second sheet made of nonwoven fabric are laminated, and an inner portion formed by folding the first sheet and the second sheet continuing from the outer portion inward at an edge of the waist opening, with at least one of the sheets extending over the entire waist portion;
the inner portion is joined to the outer portion;
The waist portion has a plurality of elongated waist elastic members provided between the outer portion and the inner portion along a width direction and spaced apart from one another,
The first sheet and the second sheet have alternately arranged in a width direction a joining position that continues in a front-rear direction across the outer portion and the inner portion and a non-joint position that continues in a front-rear direction across the outer portion and the inner portion,
the joining position has a joining portion where the first sheet and the second sheet are welded and joined,
The outer portion of the waist portion has a first portion located on the waist opening side from a middle of the waist portion in a front-to-rear direction, and a second portion located on the opposite side,
the waist portion has at least one waist elastic member at a position overlapping the first portion and at least one waist elastic member at a position overlapping the second portion,
In the first portion and the second portion, a plurality of the joint portions are intermittently arranged in a front-rear direction with non-joint portions interposed therebetween,
an area of each joint in the first portion is smaller than an area of each joint in the second portion;
A distance between the joints in the first portion in the front-rear direction is equal to or greater than a distance between the joints in the second portion in the front-rear direction.
A pants-type disposable wearing article.

(Action and Effect)
The outer body of the pants-type disposable wearing article is characterized in that the joints of the first and second sheets are intermittently provided in the first and second parts of the waist part, and the area and the front-to-back distance of each joint in the first part are different from the area and the front-to-back distance of each joint in the second part. That is, in the outer body of the pants-type disposable wearing article, the waist elastic member is covered with an outer part in which the two layers of the first and second sheets are joined, and in the first part of the outer part close to the edge of the waist opening, the area of the joints is smaller and the front-to-back distance of the joints is the same or wider, so that the outer surface of the first part feels softer against the skin, while the first and second sheets are less likely to slip when the edge of the waist opening is formed by folding back the first and second sheets and when the product is worn.
Furthermore, when the waist elastic member is covered by the portion having two layers, the first sheet and the second sheet, in the inner portion, the covered portion also feels soft to the touch of the inner surface (of the wearer).
The "front-to-rear spacing" refers to the spacing in the front-to-rear direction between adjacent joints in the front-to-rear direction (the same applies below).

<Second aspect>
In the inner portion, a plurality of the joint portions are intermittently arranged in the front-rear direction with non-joint portions interposed therebetween,
an area of each joint in the inner portion is smaller than an area of each joint in the second portion;
A distance between the joints in the inner portion in the front-rear direction is equal to or longer than a distance between the joints in the second portion in the front-rear direction.
A pants-type disposable wearing article according to a first aspect.

(Action and Effect)
By providing a joint in the inner portion within the same dimensional range as the first portion of the outer portion, the inner surface is soft to the touch, while the first and second sheets are less likely to shift when the first and second sheets are folded back to form the edge of the waist opening and when the product is worn.

<Third aspect>
the overall width of all said joints is equal;
A pants-type disposable wearing article according to the first or second aspect.

(Action and Effect)
The width of the joints may be changed in order to change the area of the joints or the spacing in the front-to-rear direction, but it is preferable that all the joints have the same width, as this increases manufacturing stability.

<Fourth aspect>
The bonding strength of all the bonding portions is equal.
The pants-type disposable wearing article according to any one of the first to third aspects.

(Action and Effect)
As described in Patent Document 2, it is preferable to vary the bonding strength of the bonding parts depending on the location, but in order to improve production stability, it is better for the bonding strength of all bonding parts to be equal.
The strength of the joint (joint strength) refers to the magnitude of the tensile force required to tear the joint per unit area or unit length.

<Fifth aspect>
the first portion has an outer edge region that is 10 mm or less from an edge of the waist opening toward the leg opening, and the inner portion has an inner edge region that is 10 mm or less from an edge of the waist opening toward the leg opening,
Among the joints located in the outer edge region and the inner edge region, one of the joints is a strong joint having a relatively high joint strength, and the other joints are weak joints having a relatively low joint strength,
the joint portion located in a region of the first portion excluding the outer edge region and in a region of the inner portion excluding the inner edge region are the weak joint portion;
The pants-type disposable wearing article according to any one of the first to fourth aspects.

(Action and Effect)
The exterior body of this pants-type disposable wearing article is characterized in that the joining portion between the first sheet and the second sheet is varied in strength (the weaker the joining strength of the nonwoven fabric by welding, the more the fibers are prevented from melting and the fabric becomes softer) and the arrangement is devised. That is, at the joining positions across the outer edge region and the inner edge region, a strong joining portion is arranged in one place, so that the first sheet and the second sheet are firmly integrated near the folding position, which makes it easy to fold the first sheet and the second sheet when folding back to form the edge of the waist opening, and makes it difficult for the first sheet and the second sheet to shift at the edge of the waist opening and in the vicinity thereof when doing so and when the product is worn.

<Sixth aspect>
The exterior body of the torso portion has a waist lower portion continuing to the leg opening side of the waist portion,
the lower waist portion includes the first sheet and the second sheet continuing from the outer portion, and a plurality of elongated lower waist elastic members provided between the first sheet and the second sheet along the width direction and spaced apart from each other,
the joining position and the non-jointing position are continuous from the waist portion to the lower waist portion,
At the joining position in the waist lower portion, the strong joining portions are adjacently disposed on both sides of the waist lower elastic member in the front-rear direction, and weak joining portions are disposed between adjacent strong joining portions between adjacent waist lower elastic members,
the size and spacing of the strong joints at the joining position of the second portion are equal to the size and spacing of the strong joints located closest to the waist opening at the joining position of the waist lower portion;
A pants-type disposable wearing article according to a fifth aspect.

(Action and Effect)
It is preferable that the arrangement of the strong and weak joints in the lower waist portion is similar to that described in Patent Document 2, but if the arrangement of the strong joints changes at the boundary between the lower waist portion and the waist portion, the texture changes suddenly, which may make the boundary more susceptible to horizontal wrinkles or cause an uncomfortable feeling. Therefore, as in this embodiment, it is preferable to provide a strong joint in the second portion and to make its dimensions and arrangement the same as those of the strong joint located closest to the waist opening in the lower waist portion.

<Seventh aspect>
The area of each joint of the first portion is 0.1 to ¹⁵ mm2;
an area of each joint of the second portion is 1.1 to 3.0 times an area of each joint of the first portion;
The distance between the joints in the first portion in the front-rear direction is 2.0 to 15 mm,
The distance between the joints in the second portion in the front-rear direction is 0.3 to 1.0 times the distance between the joints in the first portion in the front-rear direction.
The pants-type disposable wearing article according to any one of the first to sixth aspects.

(Action and Effect)
The dimensions of the joints can be determined as appropriate, but are preferably within the range of this embodiment.
<Eighth aspect>
The garment comprises an annular waist region formed by joining both sides of a front body and both sides of a rear body, a middle region extending from the waist region of the front body through a crotch region to the waist region of the rear body, a waist opening provided on the side of the waist region opposite to the middle region, leg openings provided on both sides of the middle region in the width direction, an exterior body forming at least the waist region, and an interior body attached to the exterior body so as to extend from the front body to the rear body,
The exterior body has a waist portion defined as an end portion on the waist opening side,
the waist portion has an outer portion in which a first sheet made of nonwoven fabric and a second sheet made of nonwoven fabric are laminated, and an inner portion formed by folding the first sheet and the second sheet continuing from the outer portion inwardly at an edge of the waist opening and extending over the entire waist portion,
the inner portion is joined to the outer portion;
the waist portion has a plurality of elongated waist elastic members provided at intervals between the first sheet and the second sheet in the inner portion along the width direction,
The first sheet and the second sheet have alternately arranged in a width direction a joining position that continues in a front-rear direction across the outer portion and the inner portion and a non-joint position that continues in a front-rear direction across the outer portion and the inner portion,
At the joining position, the first sheet and the second sheet have a joining portion which is welded and joined via the waist elastic member at a portion having the waist elastic member therebetween and directly at a portion not having the waist elastic member,
The outer portion of the waist portion has a first portion located on the waist opening side from a middle of the waist portion in a front-to-rear direction, and a second portion located on the opposite side,
the inner portion has at least one waist elastic member at a position overlapping the first portion and at least one waist elastic member at a position overlapping the second portion,
In the first portion and the second portion, a plurality of the joint portions are intermittently arranged in a front-rear direction with non-joint portions interposed therebetween,
an area of each joint in the first portion is smaller than an area of each joint in the second portion;
A distance between the joints in the first portion in the front-rear direction is equal to or longer than a distance between the joints in the second portion in the front-rear direction.
A pants-type disposable wearing article.

(Action and Effect)
The exterior body of the pants-type disposable wearing article is characterized in that the first and second sheets are joined intermittently in a first portion and a second portion of the waist portion, and the area and interval of each joined portion in the first portion are different from the area and interval of each joined portion in the second portion. That is, the area of the joined portion is larger and the interval of the joined portions is the same or wider in the first portion, which makes the outer surface of the first portion soft to the touch, while the first and second sheets are less likely to shift when the first and second sheets are folded back to form the edge of the waist opening and when the product is worn.

As described above, the present invention provides the advantage of preventing the sheet from shifting while improving the texture of the waist opening and its surroundings.

FIG. 2 is a plan view showing the inner surface of the pants-type disposable diaper in an unfolded state. FIG. 2 is a plan view showing the outer surface of the pants-type disposable diaper in an unfolded state. This is a cross-sectional view of FIG. 1 along line 2-2. This is a cross-sectional view of FIG. 1 along line 3-3. 1A is a cross-sectional view taken along line 4-4 of FIG. 1, and FIG. FIG. 1 is a perspective view of a pants-type disposable diaper. FIG. 2 is a plan view showing the outer surface of the inner body in the deployed state together with the contour of the outer body. 1 is a cross-sectional view of an exterior body at a joining position, the cross-sectional view showing joined and unjoined portions in an exaggerated manner. 9A is a plan view of the outer portion of the example of FIG. 8, and FIG. 9B is a plan view of the inner portion of the example of FIG. 1 is a cross-sectional view of an exterior body at a joining position, the cross-sectional view showing joined and unjoined portions in an exaggerated manner. 11A is a plan view of the outer portion of the example of FIG. 10, and FIG. 11B is a plan view of the inner portion of the example of FIG. 1 is a cross-sectional view of an exterior body at a joining position, the strong joint portion, the weak joint portion, and the non-joint portion being exaggerated and shown in schematic form. 13A is a plan view of the outer portion, and FIG. 13B is a plan view of the inner portion in the example of FIG. 12. 1 is a cross-sectional view of an exterior body at a joining position, the strong joint portion, the weak joint portion, and the non-joint portion being exaggerated and shown in schematic form. 15A is a plan view of the outer portion of the example of FIG. 14, and FIG. 15B is a plan view of the inner portion of the example of FIG.

A pants-type disposable diaper will be described below in detail as an example of a pants-type disposable wearing article with reference to the attached drawings. Each component adjacent in the thickness direction is fixed or joined as necessary in the same manner as known diapers, except for the fixed or joined parts described below. The dotted parts in the cross-sectional view indicate an adhesive such as a hot melt adhesive as the fixing or joining means. The hot melt adhesive can be applied by known methods such as slot application, continuous line or dotted line bead application, spiral, Z-shaped, wavy, etc. spray application, or pattern coating (transfer of hot melt adhesive by letterpress printing method). Alternatively or in addition to this, at the fixing part of the elastic member, the hot melt adhesive can be applied to the outer circumferential surface of the elastic member to fix the elastic member to the adjacent member. As the hot melt adhesive, for example, EVA-based, adhesive rubber-based (elastomer-based), polyolefin- based, polyester-polyamide-based, and other types are available, but they can be used without any particular limitation. As a fixing or joining means for joining each component, a material welding means such as heat sealing or ultrasonic sealing can also be used. In a portion where liquid permeability in the thickness direction is required, adjacent components in the thickness direction are fixed or joined in an intermittent pattern. For example, when such intermittent fixing or joining is performed with a hot melt adhesive, intermittent pattern coating in a spiral, Z-shape, wave shape, etc. can be suitably used, and when coating an area greater than the coating width of one nozzle, intermittent pattern coating in a spiral, Z-shape, wave shape, etc. can be performed with or without gaps in the width direction. As a joining means for joining each component, material welding means such as heat sealing and ultrasonic sealing can also be used.

In addition, as the nonwoven fabric in the following description, known nonwoven fabrics can be appropriately used depending on the part and purpose. The constituent fibers of the nonwoven fabric can be selected without particular limitation, for example, synthetic fibers such as polyolefins such as polyethylene or polypropylene, polyesters, polyamides, etc. (including single-component fibers and composite fibers such as core-sheath fibers), regenerated fibers such as rayon and cupra, natural fibers such as cotton, etc., and these can also be used in combination. In order to increase the flexibility of the nonwoven fabric, it is preferable to use crimped fibers as the constituent fibers. In addition, the constituent fibers of the nonwoven fabric may be hydrophilic fibers (including fibers that have been made hydrophilic by a hydrophilizing agent), hydrophobic fibers, or water-repellent fibers (including fibers that have been made water-repellent by a water-repellent agent). Furthermore, nonwoven fabrics are generally classified into staple fiber nonwoven fabrics, long fiber nonwoven fabrics, spunbond nonwoven fabrics, meltblown nonwoven fabrics, spunlace nonwoven fabrics, thermal bond (air-through) nonwoven fabrics, needle punched nonwoven fabrics, point bond nonwoven fabrics, laminated nonwoven fabrics (SMS nonwoven fabrics, SMMS nonwoven fabrics, etc. in which a meltblown layer is sandwiched between spunbond layers), etc., depending on the fiber length, sheet formation method, fiber bonding method, and laminated structure, and any of these nonwoven fabrics can be used.

1 to 6 show a pants-type disposable diaper. This pants-type disposable diaper includes a rectangular front exterior body 12F constituting at least the waist circumference of the front body F, a rectangular rear exterior body 12B constituting at least the waist circumference of the rear body B, and an inner body 200 provided inside the exterior bodies 12F, 12B so as to extend from the front exterior body 12F through the crotch region to the rear exterior body 12B. Both sides of the front exterior body 12F and both sides of the rear exterior body 12B are joined to form side seals 12A, and an opening formed by the front and rear ends of the exterior bodies 12F, 12B becomes a waist opening WO through which the wearer's torso passes, and the portions on both sides of the inner body 200 in the width direction that are surrounded by the lower edges of the exterior bodies 12F, 12B and the side edges of the inner body 200 respectively become leg openings LO through which the legs pass. The inner body 200 is a part that absorbs and retains excrement such as urine, and the outer bodies 12F and 12B are parts that support the inner body 200 against the wearer's body. Also, the symbol Y indicates the overall length of the diaper in the unfolded state (the length in the front-to-rear direction from the edge We of the waist opening WO of the front body F to the edge We of the waist opening WO of the back body B), and the symbol X indicates the overall width of the diaper in the unfolded state.

This pants-type disposable diaper has an annular waist region T formed by joining both sides of the front body F and both sides of the back body B with side seals 12A, a middle region L extending from the waist region T of the front body F through the crotch region to the waist region T of the back body B, a waist opening WO provided on the opposite side of the middle region L in the waist region T, and leg openings LO provided on both sides in the width direction WD of the middle region L. In other words, the waist region T is defined as the range in the front-rear direction LD from the waist opening WO to the upper end of the leg opening LO, and the middle region L is defined as the range in the front-rear direction LD between the lower end of the side seal 12A of the front body F and the lower end of the side seal 12A of the back body B. In the unfolded state shown in Figures 1 and 2, both side edges of the middle region L are narrowed in a U-shape or curved shape to fit the wearer's legs, and the overall shape of the diaper is approximately hourglass-shaped.

The pants-type disposable diaper also includes two main assemblies, namely, outer bodies 12F and 12B that form at least the waist region T, and an inner body 200 that is attached to the outer bodies 12F and 12B so as to extend from the front body F to the rear body B.

(Interior body)
The inner body 200 is rectangular in the illustrated example, but may have any shape. As shown in Figures 3 to 5, the inner body 200 is a main body that is provided with a top sheet 30 that faces the body, a liquid-impermeable sheet 11, and an absorbent element 50 interposed therebetween, and is responsible for the absorption function. Reference numeral 40 denotes an intermediate sheet that is provided between the top sheet 30 and the absorbent element 50 in order to quickly transfer liquid that has permeated the top sheet 30 to the absorbent element 50, and reference numeral 60 denotes rising gathers 60 that extend from both sides of the inner body 200 so as to contact the wearer's legs in order to prevent excrement from leaking out to both sides of the inner body 200.

(Top sheet)
The top sheet 30 is a material that has a property of being permeable to liquid, and examples of such material include a nonwoven fabric with or without holes, a plastic sheet with holes, etc. The top sheet 30 may be made of a single sheet, or may be made of a laminated sheet obtained by bonding two or more sheets together. Similarly, the top sheet 30 may be made of a single sheet, or may be made of two or more sheets in the planar direction.

Both sides of the top sheet 30 may be folded back at the side edges of the absorbent element 50, or may not be folded back and extend beyond the side edges of the absorbent element 50.

The top sheet 30 is preferably fixed to the adjacent backside member by a material welding joining means such as heat sealing or ultrasonic sealing, or by a hot melt adhesive, in order to prevent misalignment relative to the backside member. In the illustrated example, the top sheet 30 is fixed to the front surface of the intermediate sheet 40 and the front surface of the portion of the packaging sheet 58 that is located on the front side of the absorbent body 56 by a hot melt adhesive applied to the backside of the top sheet 30.

(middle seat)
In order to quickly transfer liquid that has permeated the top sheet 30 to the absorbent body 56, an intermediate sheet (also called a "second sheet") 40 that has a faster liquid permeability rate than the top sheet 30 can be provided. This intermediate sheet 40 is intended to quickly transfer liquid to the absorbent body 56, improve the absorption performance of the absorbent body 56, and prevent the "backflow" phenomenon of absorbed liquid from the absorbent body 56. The intermediate sheet 40 can also be omitted.

Examples of the intermediate sheet 40 include the same material as the top sheet 30, spunlace nonwoven fabric, spunbond nonwoven fabric, SMS nonwoven fabric, pulp nonwoven fabric, mixed sheet of pulp and rayon, point-bond nonwoven fabric, and crepe paper. In particular, air-through nonwoven fabric is preferred because it is bulky. For the air-through nonwoven fabric, it is preferred to use composite fibers with a core-sheath structure, and in this case, the resin used for the core may be polypropylene (PP), but polyester (PET) with high rigidity is preferred. The basis weight is preferably 17 to 80 g/m ² , and more preferably 17 to 50 g/m ^2. The thickness of the raw fiber of the nonwoven fabric is preferably 2.0 to 10 dtex. In order to make the nonwoven fabric bulky, it is also preferred to use eccentric fibers with no core in the center, hollow fibers, or eccentric and hollow fibers as the mixed fibers of all or part of the raw fiber.

In the illustrated example, the intermediate sheet 40 is positioned in the center and is shorter than the width of the absorbent body 56, but it may be provided across the entire width. The length of the intermediate sheet 40 in the front-to-rear direction LD may be the same as the entire length of the diaper, the same as the length of the absorbent element 50, or within a short length range centered on the area that receives liquid.

The intermediate sheet 40 is preferably fixed to the adjacent backside member by a material welding joining means such as heat sealing or ultrasonic sealing, or by a hot melt adhesive, in order to prevent misalignment relative to the backside member. In the illustrated example, the intermediate sheet 40 is fixed to the surface of the portion of the packaging sheet 58 that is located on the front side of the absorbent body 56 by a hot melt adhesive applied to the backside.

(Liquid-impermeable sheet)
The material of the liquid-impermeable sheet 11 is not particularly limited, but examples thereof include plastic films made of polyolefin resins such as polyethylene and polypropylene, laminated nonwoven fabrics in which a plastic film is provided on the surface of a nonwoven fabric, and laminated sheets in which a nonwoven fabric is layered and bonded to a plastic film. For the liquid-impermeable sheet 11, it is preferable to use a material that is liquid-impermeable and moisture-permeable and is preferably used from the viewpoint of preventing stuffiness. As a moisture-permeable plastic film, a microporous plastic film obtained by kneading an inorganic filler into a polyolefin resin such as polyethylene or polypropylene, forming a sheet, and then stretching it in a uniaxial or biaxial direction is widely used. In addition, sheets that have been made liquid-impermeable without using a plastic film by methods such as nonwoven fabric using microdenier fibers, strengthening leak-proofing by reducing the voids in the fibers through the application of heat or pressure, and coating with a highly absorbent resin or a hydrophobic resin or a water repellent agent can also be used as the liquid-impermeable sheet 11, but it is preferable to use a resin film in order to obtain sufficient adhesive strength when bonded to the cover nonwoven fabric 13 described below via a hot melt adhesive.

The liquid-impermeable sheet 11 is made to be wide enough to fit behind the absorbent element 50 as shown in the figure, but in order to improve leak-proofing, it can also be made to wrap around both sides of the absorbent element 50 and extend to both sides of the top sheet 30 of the absorbent element 50. The appropriate width of this extension is about 5 to 20 mm on each side.

(Rise and gather)
The rising gathers 60 extend along both sides of the inner body 200 over the entire length in the front-rear direction LD, and are provided to come into contact with the legs of the wearer to prevent side leakage. If necessary, the rising gathers 60 can be omitted.

The rising gathers 60 (so-called three-dimensional gathers) shown in Figures 1, 3, and 4 rise from the side of the inner body 200 to the front side. The root side portion 60B of these rising gathers 60 rises diagonally toward the center in the width direction, and the tip side portion 60A from the middle portion rises diagonally toward the outside in the width direction, but this is not limited to this and appropriate modifications are possible, such as a form in which the gathers as a whole rise toward the center in the width direction.

Explaining in more detail, the rising gathers 60 in the illustrated example are formed by folding back a strip-shaped gathered nonwoven fabric 62 having a length equal to the front-rear length of the inner body 200 in the width direction WD at its tip and folding it in two, and fixing a plurality of elongated gathered elastic members 63 at intervals in the width direction WD between the folded-back portion and the sheet in the vicinity of the folded-back portion. The base end portion of the rising gathers 60 located opposite the tip portion (the end portion opposite the folded-back portion of the sheet in the width direction WD) is a root portion 65 fixed to the side portion on the back side of the liquid-impermeable sheet 11 of the inner body 200, and the portion other than the root portion 65 is a main portion 66 (portion on the folded-back portion side) extending from the root portion 65. The main body portion 66 has a root side portion 60B extending toward the center in the width direction, and a tip side portion 60A that is folded back at the tip of the root side portion 60B and extends outward in the width direction. This form is a surface contact type of risen gather 60, but a line contact type of risen gather 60 that is not folded back outward in the width direction can also be used. The front-rear direction ends of the main body portion 66 are fallen portions 67 that are fixed in a fallen state to the side surfaces of the top sheet 30, while the front-rear direction intermediate portion between them is an unfixed free portion 68, and a gather elastic member 63 along the front-rear direction LD is fixed in a stretched state to at least the tip of this free portion 68.

In the rise-up gathers 60 configured as described above, the contractile force of the gather elastic member 63 acts to bring the front-rear end closer together, but while the front-rear end of the main body portion 66 is fixed so that it does not stand up, the area between them is an unfixed free portion 68, so that only the free portion 68 stands up so as to abut against the body side as shown by the arrow in Figure 3. In particular, when the root portion 65 is located on the back side of the inner body 200, the free portion 68 stands up so as to open outward in the width direction in the crotch area and its vicinity, so that the rise-up gathers 60 come into contact with the leg circumference with a surface, improving the fit.

In the illustrated example of the rising gather 60, in a bent form in which the main body portion 66 is made up of a root side portion 60B extending toward the center in the width direction and a tip side portion 60A folded back at the tip of the root side portion 60B and extending outward in the width direction, the tip side portion 60A and the root side portion 60B are joined in a fallen state at the fallen portion 67, and the root side portion 60B is joined in a fallen state to the top sheet 30. At least one of various hot melt adhesives applied by various methods and material welding means such as heat sealing and ultrasonic sealing can be used to join the opposing surfaces at the fallen portion 67. In this case, the joining of the root side portion 60B and the top sheet 30 and the joining of the tip side portion 60A and the root side portion 60B may be performed by the same means or by different means. For example, one preferred embodiment is to bond the base portion 60B to the top sheet 30 with a hot melt adhesive, and to bond the tip portion 60A to the base portion 60B by material welding.

As the gathered nonwoven fabric 62, a nonwoven fabric that is soft and has excellent uniformity and hiding properties, such as a spunbond nonwoven fabric (SS, SSS, etc.), an SMS nonwoven fabric (SMS, SSMMS, etc.), or a meltblown nonwoven fabric, which is treated with a water repellent treatment using silicone or the like as necessary, can be suitably used, and the fiber basis weight is preferably about 10 to 30 g/ ^m2 . As the gathered elastic member 63, a rubber thread or the like can be used. When a spandex rubber thread is used, the thickness is preferably 470 to 1240 dtex, and more preferably 620 to 940 dtex. The elongation rate at the time of fixing is preferably 150 to 350%, and more preferably 200 to 300%. Also, as shown in the figure, a waterproof film 64 can be interposed between the gathered nonwoven fabric 62 folded in two, in which case the gathered nonwoven fabric 62 can be partially omitted where the waterproof film 64 is present; however, in order to make the product look and feel like cloth, it is necessary that at least the outer surface from the base end to the tip of the rising gathers 60 be formed of gathered nonwoven fabric 62, as in the example shown.

The number of gather elastic members 63 provided in the free portion 68 of the rising gathers 60 is preferably 2 to 6, and more preferably 3 to 5. The appropriate spacing is 3 to 10 mm. This configuration makes it easier for the gather elastic members 63 to come into contact with the skin in the area in which they are arranged. The gather elastic members 63 may be arranged not only on the tip side but also on the base side.

In the free portion 68 of the rising gather 60, at least one of various application methods of hot melt adhesive and material welding such as heat sealing and ultrasonic sealing can be used to bond the inner layer and outer layer of the gathered nonwoven fabric 62 together and to fix the gathered elastic member 63 sandwiched between them. If the entire surfaces of the inner layer and outer layer of the gathered nonwoven fabric 62 are bonded together, flexibility is lost, so it is preferable that the parts other than the adhesive part of the gathered elastic member 63 are not bonded or are weakly bonded. In the illustrated example, hot melt adhesive is applied only to the outer peripheral surface of the gathered elastic member 63 by an application means such as a comb gun or a surwrap nozzle, and the gathered nonwoven fabric 62 is sandwiched between the inner layer and the outer layer, so that the gathered elastic member 63 is fixed to the inner layer and the outer layer of the gathered nonwoven fabric 62 and the inner layer and the outer layer of the gathered nonwoven fabric 62 are fixed only by the hot melt adhesive applied to the outer peripheral surface of the gathered elastic member 63.

Similarly, the waterproof film 64 incorporated in the rising gathers 60 can be fixed to the gathered nonwoven fabric 62, and the fallen portion 67 can be fixed using at least one of a variety of hot melt adhesives applied by various methods and material welding methods such as heat sealing and ultrasonic sealing.

(Absorption element)
The absorbent element 50 has an absorbent body 56 and a wrapping sheet 58 that wraps the entire absorbent body 56. The wrapping sheet 58 may be omitted.

(Absorber)
The absorbent body 56 can be formed by a fiber assembly. As the fiber assembly, in addition to stacked staple fibers such as cotton-like pulp and synthetic fibers, a filament assembly obtained by opening a tow (fiber bundle) of synthetic fibers such as cellulose acetate as necessary can be used. The fiber basis weight can be, for example, about 100 to 300 g/m ² when stacking cotton-like pulp or staple fibers, and can be, for example, about 30 to 120 g/m ² when the filament assembly is used. The fineness of the synthetic fibers is, for example, 1 to 16 dtex, preferably 1 to 10 dtex, and more preferably 1 to 5 dtex. In the case of a filament assembly, the filaments may be non-crimped fibers, but are preferably crimped fibers. The crimp degree of the crimped fibers can be, for example, about 5 to 75, preferably 10 to 50, and more preferably 15 to 50, per 2.54 cm. Also, uniformly crimped fibers can be used. It is preferable that highly absorbent polymer particles are dispersed and held within the absorbent body 56.

The absorbent body 56 may be rectangular in shape, but as shown in FIG. 7 and other figures, it is preferable to have an hourglass shape with a narrower constricted portion 56N in the middle in the front-to-rear direction than the front and rear ends, as this improves the fit of the absorbent body 56 itself and the rising gathers 60 around the legs.

The dimensions of the absorbent body 56 can be determined as appropriate as long as they extend in all directions from the urination opening position, but it is preferable that the absorbent body 56 extend to the periphery of the inner body 200 or its vicinity in the front-to-back direction LD and width direction WD. The symbol 56X indicates the overall width of the absorbent body 56.

(Superabsorbent polymer particles)
The absorbent body 56 may contain superabsorbent polymer particles in part or in its entirety. The superabsorbent polymer particles include not only "particles" but also "powder". As the superabsorbent polymer particles, those used in this type of disposable diaper can be used as they are. For example, it is preferable that the proportion of particles remaining on a 500 μm standard sieve (JIS Z8801-1:2006) when sieved (shaking for 5 minutes) is 30% by weight or less, and it is also preferable that the proportion of particles remaining on a 180 μm standard sieve (JIS Z8801-1:2006) when sieved (shaking for 5 minutes) is 60% by weight or more.

There are no particular limitations on the material that can be used for the superabsorbent polymer particles, but those with a water absorption capacity of 40 g/g or more are preferred. Superabsorbent polymer particles include starch-based, cellulose-based and synthetic polymer-based materials, and examples of materials that can be used include starch-acrylic acid (salt) graft copolymers, saponified starch-acrylonitrile copolymers, crosslinked products of sodium carboxymethylcellulose and acrylic acid (salt) polymers. The shape of the superabsorbent polymer particles is preferably the commonly used powder-like form, but other shapes can also be used.

For example, highly absorbent polymer particles with a water absorption speed of 70 seconds or less, particularly 40 seconds or less, are preferably used. If the water absorption speed is too slow, the liquid supplied to the absorbent body 56 is likely to flow back out of the absorbent body 56, which is known as backflow.

The highly absorbent polymer particles preferably have a gel strength of, for example, 1000 Pa or more. This effectively prevents the sticky feeling after absorbing liquid, even when the absorbent body 56 is bulky.

The basis weight of the highly absorbent polymer particles can be appropriately determined depending on the absorption amount required for the application of the absorbent body 56. Therefore, although it cannot be generally stated, it can be set to 50 to 350 g/ ^m2 .

(packaging sheet)
When the wrapping sheet 58 is used, the material may be tissue paper, particularly crepe paper, nonwoven fabric, polylaminated nonwoven fabric, a sheet with small holes, or the like. However, it is preferable that the sheet is one from which the superabsorbent polymer particles do not escape. When using nonwoven fabric instead of crepe paper, hydrophilic SMS nonwoven fabric (SMS, SSMMS, etc.) is particularly suitable, and the material may be polypropylene, a polyethylene/polypropylene composite, or the like. The basis weight is preferably 5 to 40 g/ ^m2 , particularly 10 to 30 g/ ^m2 .

The packaging form of the packaging sheet 58 can be determined as appropriate, but from the standpoint of ease of manufacture and prevention of leakage of superabsorbent polymer particles from the front and rear edges, it is preferable to wrap the sheet around the front and rear surfaces and both sides of the absorbent body 56 in a cylindrical shape, with the front and rear edges extending beyond the front and rear of the absorbent body 56, and to join the overlapping parts of the wrap and the overlapping parts of the protruding front and rear edges with a joining means such as a hot melt adhesive or material welding.

(Exterior body)
The exterior bodies 12F, 12B in the illustrated example are composed of a rectangular front exterior body 12F that forms the waist region T of the front body F and a rectangular rear exterior body 12B that forms the waist region T of the back body B, and the front exterior body 12F and the rear exterior body 12B are not continuous on the crotch side, but are separated in the front-to-rear direction LD. This separation distance 12d can be, for example, about 150 to 250 mm. The exterior bodies 12F, 12B may be an integrated body that is continuous from the front body F to the back body B through the crotch area.

The portion of the outer body 12F, 12B located in the waist region T can be divided into a waist portion W that forms the end on the waist opening WO side, and a lower waist portion U that is the portion below this. If the portion of the outer body 12F, 12B located in the waist region T has a boundary where the stretching force in the width direction WD changes (for example, the thickness or elongation rate of the elastic member changes), the waist portion W is the portion closer to the waist opening WO than the boundary located closest to the waist opening WO side, and if there is no such boundary, the waist extension portion 12E that extends further toward the waist opening WO side than the absorbent body 56 or the inner body 200 is the waist portion W. The length of these in the front-rear direction LD varies depending on the size of the product and can be determined appropriately, but as an example, the waist portion W can be 15 to 40 mm, and the lower waist portion U can be 65 to 120 mm.

In the illustrated example, the front exterior body 12F and the rear exterior body 12B have the same dimensions in the front-to-rear direction LD and do not have a portion located in the middle region L, but as shown by the two-dot chain line in FIG. 7, the rear exterior body 12B has a longer front-to-rear dimension than the front exterior body 12F, and the front exterior body 12F does not have a portion located in the middle region L, but the rear exterior body 12B may have a buttocks cover portion C extending from the waist region T to the middle region L. Although not shown, the front exterior body 12F may also be provided with a groin cover portion extending from the waist region T to the middle region L, or a configuration may be used in which a groin cover portion is provided but a buttocks cover portion is not provided.

The exterior bodies 12F, 12B incorporate elastic members 15, 17 to improve the fit around the wearer's waist, and form an elastic region A2 that elastically expands and contracts in the width direction WD with the expansion and contraction of the elastic members 15, 17. In this elastic region A2, the exterior bodies 12F, 12B contract with the contraction of the elastic members when in their natural length state, forming wrinkles or folds, and when stretched in the longitudinal direction of the elastic members, they can be stretched to a predetermined extension rate at which they are fully stretched without wrinkles. The elastic members 15, 17 can be any known elongated elastic member, such as a thread or strip, without any particular restrictions. The elastic members 15, 17 may be made of synthetic or natural rubber.

To explain the elastic members 15, 17 in the illustrated example in more detail, a plurality of waist elastic members 17 are attached to the waist portion W of the outer body 12F, 12B at intervals in the front-rear direction so as to be continuous over the entire width direction WD. Furthermore, one or more of the waist elastic members 17 arranged in the region adjacent to the waist lower portion U may overlap the inner body 200, or may be provided on both sides in the width direction except for the width direction central portion overlapping with the inner body 200. The waist elastic members 17 preferably comprise 2 to ¹⁵ , and especially 4 to 10, rubber threads having a thickness of 155 to 1880 dtex, especially 470 to 1240 dtex (in the case of synthetic rubber; in the case of natural rubber, a cross-sectional area of 0.05 to 1.5 mm2, especially 0.1 to ^1.0 mm2) spaced at intervals of 2 to 12 mm, especially 3 to 7 mm, and the resulting elongation rate in the width direction WD of the waist portion W is preferably 150 to 400%, especially 220 to 320%. The spacing of the waist elastic members 17 in the front-to-back direction LD may be constant, or may vary midway in the front-to-back direction LD.

In addition, it is preferable that a plurality of waist lower elastic members 15 made of elongated elastic members are attached to the waist lower portion U of the outer casings 12F, 12B at intervals in the front-rear direction. The waist lower elastic members 15 are preferably about 5 to 30 pieces of rubber thread having a thickness of 155 to 1880 dtex, especially 470 to 1240 dtex (in the case of synthetic rubber; in the case of natural rubber, a cross-sectional area of 0.05 to 1.5 ^mm2 , especially 0.1 to ^1.0 mm2) at intervals of 1 to 15 mm, especially 3 to 8 mm, and the stretch rate of the waist lower portion U in the width direction WD is preferably about 200 to 350%, especially 240 to 300%. The intervals of the waist lower elastic members 15 in the front-rear direction LD may be constant, or may vary in the middle of the front-rear direction LD as in the illustrated example.

When the waist lower elastic member 15 is provided in the front-to-rear range including the absorbent body 56, as in the illustrated example of the waist lower part U, in order to prevent contraction of the absorbent body 56 in the width direction WD in part or all of it, the widthwise middle including part or all of the part overlapping with the absorbent body 56 in the width direction WD (preferably including the entire interior joint parts 201, 202) is made into a non-stretchable region A1, and both sides in the width direction are made into stretchable regions A2. It is preferable that the waist part W is made into a stretchable region A2 over the entire width direction WD, but as with the waist lower part U, a non-stretchable region A1 may be provided in the widthwise middle.

Such stretchable region A2 and non-stretchable region A1 can be constructed by fixing the elastic member 15 during the manufacture of the exterior bodies 12F, 12B, and then cutting the waist-lower elastic member 15 in the region that will become the non-stretchable region A1 at one location in the middle of the width direction using pressure and heat, or by cutting it finely at multiple locations, so that stretchability is retained in the stretchable region A2 while eliminating stretchability in the non-stretchable region A1. In these cases, cut pieces 16 of the elastic member that do not substantially contribute to stretching will remain in the exterior bodies 12F, 12B in the non-stretchable region A1.

(Laminated structure of exterior body)
8 and 9, the waist portion W has an outer portion 18 in which a first sheet 12S made of nonwoven fabric and a second sheet 12H made of nonwoven fabric are laminated, and an inner portion 19 formed by folding the first sheet 12S and the second sheet 12H continuing from the outer portion 18 inward at the edge We of the waist opening WO, and the first sheet 12S extends over the entire waist portion W, and the inner portion 19 is joined to the outer portion 18 via a hot melt adhesive HM (or by welding). In the illustrated example, the first sheet 12S and the second sheet 12H of the outer portion 18 extend from the waist portion W to the lower waist portion U (over the entire torso region T in the illustrated example), but this is not limited thereto, and appropriate modifications are possible, such as forming the lower waist portion U with a different sheet. In addition, in the illustrated example, the second sheet 12H of the inner portion 19 extends only to the middle of the waist portion W in the front-to-back direction LD, and the first sheet 12S extends from the waist portion W to the lower waist portion U and covers the end of the inner body 200 on the waist opening WO side, but this is not limited to this, and for example, both the first sheet 12S and the second sheet 12H may extend to the lower waist portion U, or both the first sheet 12S and the second sheet 12H may be contained within the waist portion W, or they may extend only further than the waist opening WO side of the inner body 200 and not cover the end of the inner body 200.

The material of the first sheet 12S and the second sheet 12H can be appropriately determined as long as it is a nonwoven fabric. For example, the first sheet 12S and the second sheet 12H can be a nonwoven fabric made of synthetic fibers such as polyolefins such as polyethylene and polypropylene, polyesters, and polyamides, or mixed fibers or composite fibers using two or more of these. Examples of a method for bonding fibers include an air-through method and a point bond method. The fineness, basis weight, and thickness of the nonwoven fabric used for the first sheet 12S and the second sheet 12H can be appropriately determined. As an example, the nonwoven fabric used for the first sheet 12S and the second sheet 12H is preferably a long-fiber nonwoven fabric with a fineness of 1.0 to 2.5 dtex, a basis weight of 10 to 30 g/m ² , and a thickness of 0.15 to 0.50 mm.

8 and 9, the waist elastic member 17 provided in the waist portion W is provided between the outer portion 18 and the inner portion 19. In the illustrated example, the waist elastic member 17 is fixed to the second sheet 12H of the outer portion 18 and the inner portion 19 by hot melt adhesive HM applied to its outer peripheral surface, but it may be fixed by welding. When the waist portion W is at its natural length, it shrinks in the width direction WD together with the waist elastic member 17, forming wrinkles, but when it is worn and stretched to a certain extent in the width direction WD together with the waist elastic member 17, the wrinkles spread out, and when it is unfolded, the wrinkles disappear completely.

The waist lower elastic member 15 provided in the waist lower portion U is provided between the first sheet 12S and the second sheet 12H continuing from the outer portion 18, but is not limited thereto and may be provided between other sheets. In the illustrated example, the waist lower elastic member 15 is fixed to the first sheet 12S and the second sheet 12H by welding at a joining position 90 described later, but is not limited thereto and may be fixed to the first sheet 12S and the second sheet 12H by a hot melt adhesive HM applied to the outer peripheral surface of the waist lower elastic member 15. The waist lower portion U shrinks in the width direction WD together with the waist lower elastic member 15 in the natural length state and wrinkles are formed, but when the waist lower portion U is stretched to a certain extent in the width direction WD together with the waist lower elastic member 15 in the worn state, the wrinkles spread, and when the waist lower elastic member 15 is expanded to a certain extent in the width direction WD, the wrinkles disappear completely in the unfolded state.

The first sheet 12S and the second sheet 12H have alternately arranged in the width direction WD, joint positions 90 that continue in the front-to-back direction LD across the outer portion 18 and the inner portion 19, and non-joint positions 91 that continue in the front-to-back direction LD across the outer portion 18 and the inner portion 19, and each joint position 90 has a joint portion 80 where the first sheet 12S and the second sheet 12H are welded together. In the illustrated example, the joint positions 90 and non-joint positions 91 having this joint portion 80 continue not only to the waist portion W but also to the lower waist portion U. Here, the state where the first sheet 12S and the second sheet 12H are welded and joined includes not only a state where almost all the fibers of the first sheet 12S and the second sheet 12H are melted and integrated (for example, less than 10 fibers may protrude) and become a film-like shape (higher transparency than the surroundings), but also a state where almost all the fibers of the layers on the joining surface side of both the first sheet 12S and the second sheet 12H are welded and the fibers of the layers on the opposite surface side are not welded and remain independent, or a state where only some of the fibers located on at least one of the joining surfaces of the first sheet 12S and the second sheet 12H are welded. It is preferable that the opposing surfaces of the first sheet 12S and the second sheet 12H are not bonded over their entirety with the hot melt adhesive HM, but they may be partially bonded as necessary, for example, at both ends of the waist lower elastic member 15. The joining position 90 may be a straight line along the front-rear direction LD as shown in the figure, or may be an oblique straight line inclined at 0 to 30 degrees to the front-rear direction LD, or a wavy line. The width of the joining position 90 (width of the joining parts 81, 82) and the spacing in the width direction WD (width of the non-joint position 91) may be determined as appropriate, but for example, the width of the joining position 90 can be about 0.1 to 5 mm, particularly about 0.5 to 3 mm, and the spacing in the width direction WD can be about 3 to 10 mm, particularly about 3 to 5 mm. In addition, as a processing method for welding and joining, in addition to ultrasonic sealing, heat sealing by heating a roll can be used.

The outer portion 18 has a first portion P1 located on the waist opening WO side from the middle in the front-to-back direction LD, and a second portion P2 located on the opposite side, and the waist portion W has at least one waist elastic member 17 at a position overlapping the first portion P1 and the second portion P2. Characteristically, the first portion P1 and the second portion P2 each have a plurality of joints 80 intermittently arranged in the front-to-back direction LD via non-jointed portions 83, the area of each joint 80 in the first portion P1 is smaller than the area of each joint 80 in the second portion P2, and the distance k1 in the front-to-back direction LD between the joints 80 in the first portion P1 is the same as or larger than the distance k2 in the front-to-back direction LD between the joints 80 in the second portion P2.

In this way, the waist elastic member 17 is covered with the outer portion 18 formed by joining the first sheet 12S and the second sheet 12H, and the outer portion 18 has a smaller area of the joint 80 in the first portion P1 near the edge We of the waist opening WO, and the distance k1 of the joint 80 is the same or wider. Therefore, the outer surface of the first portion P1 feels softer to the touch, but the first sheet 12S and the second sheet 12H are less likely to slip when the first sheet 12S and the second sheet 12H are folded back to form the edge We of the waist opening WO, and when the product is worn. Also, as shown in FIG. 8, when the waist elastic member 17 is covered with the portion of the inner portion 19 having the two layers of the first sheet 12S and the second sheet 12H, the inner surface (to the wearer's) feels soft to the touch in the covered portion.

The inner portion 19 may also have a joint 80 within the same dimensional range as the first portion P1 of the outer portion 18. That is, the inner portion 19 has a plurality of joints 80 intermittently arranged in the front-to-back direction LD via non-jointed portions 83, and the area of each joint 80 in the inner portion 19 is smaller than the area of each joint 80 in the second portion P2, and the spacing k4 in the front-to-back direction LD of the joints 80 in the inner portion 19 is the same as or longer than the spacing k2 in the front-to-back direction LD of the joints 80 in the second portion P2. This is preferable because it makes the inner surface soft to the touch, while preventing the first sheet 12S and the second sheet 12H from shifting easily when the first sheet 12S and the second sheet 12H are folded back to form the edge We of the waist opening WO and when the product is worn. As shown in the example in Figures 8 and 9, when one of the first sheet 12S and the second sheet 12H of the inner portion 19 extends further toward the center in the front-to-rear direction LD than the other sheet, the extended portion may have a trace 80m similar to the joint 80, or may not have any trace at all. Also, when this one sheet extends to the lower waist portion U, the trace 80m similar to the joint 80 may remain partway (illustrated example) or over the entire extended portion, or may not have any trace at all.

It is preferable that the outer portion 18 does not have a joint 80 in the area from the edge We of the waist opening WO to a position 3 mm away from the crotch area. Similarly, it is preferable that the inner portion 19 does not have a joint 80 in the area from the edge We of the waist opening WO to a position 3 mm away from the crotch area.

The position of the boundary between the first portion P1 and the second portion P2 can be determined as appropriate, but it is preferable that it be located in the central region when the area between the waist elastic member 17 closest to the waist opening WO and the waist elastic member 17 closest to the leg opening LO is divided into three equal parts in the front-to-back direction LD.

The area of the joints 80 can be determined as appropriate, but for example, the area of each joint 80 in the first portion P1 is preferably 0.1 to ¹⁵ mm2, and more preferably 1 to ¹⁰ mm2. The area of each joint 80 in the second portion P2 is preferably 1.1 to 3.0 times, and more preferably 1.5 to 2.5 times, the area of each joint 80 in the first portion P1. When the joints 80 are provided up to the lower waist portion U, as in the outer portion 18 of the illustrated example, the area of each joint 80 in the lower waist portion U can be the same as or larger than the area of each joint 80 in the second portion P2.

The total lengths j1, j2 and total widths s1, s2 of each joint 80 can be determined as appropriate, but for example, the total length j1 of the first portion P1 is preferably 0.5 to 3 mm, and more preferably 1 to 2 mm. The total length j2 of the joint 80 of the second portion is preferably 1.1 to 3.0 times the total length j1 of the first portion P1, and more preferably 2 to 3 times. The total width s1 of the first portion P1 is preferably 0.1 to 3.0 mm, and more preferably 0.3 to 2.0 mm. The total width s2 of the joint 80 of the second portion is preferably 1.0 to 1.5 times the total width s1 of the first portion P1, and more preferably 1.0 to 1.2 times. When the joints 80 are provided up to the lower waist portion U, as in the outer portion 18 in the illustrated example, the total length j3 and total width s3 of each joint 80 in the lower waist portion U can be equal to or greater than the total length j2 and total width s2 of each joint 80 in the second portion P2.

The distances k1, k2 in the front-rear direction LD of each joint 80 can be appropriately determined, but for example, the distance k1 in the front-rear direction LD of the joint 80 in the first part P1 is preferably 2 to 15 mm, more preferably 5 to 10 mm. The distance k2 in the front-rear direction LD of the joint 80 in the second part P2 is preferably 0.3 to 1.0 times the distance k1 in the front-rear direction LD of the joint 80 in the first part P1, more preferably 0.5 to 1.0 times. When the joint 80 is provided up to the lower waist part U, as in the outer part 18 of the illustrated example, the distance k3 in the front-rear direction LD of the joint 80 in the lower waist part U can be the same as or shorter than the distance k2 in the front-rear direction LD of the joint 80 in the second part P2. Also, the joint 80 may be continuous (the distance in the front-to-back direction LD is zero) from the waist lower elastic member 15 that is closest to the waist opening WO in the waist lower portion U to the waist lower elastic member 15 that is farthest from the waist opening WO.

The shape of the joint 80 can be determined as appropriate, for example, a rectangular shape as shown in the example, a parallelogram or trapezoid with both ends inclined in the front-to-rear direction LD, a polygonal shape such as a triangle or pentagon, a circle or ellipse, a star shape or a cloud shape, or the like.

The overall width of the joints 80 may be changed depending on the location in order to change the area and spacing of the joints 80, but it is preferable that the overall width of all the joints 80 is the same, as this increases manufacturing stability. In this case, it is preferable that the joints 80 have a shape with a pair of parallel sides along the front-to-rear direction LD (for example, a rectangular shape as in the illustrated example, a parallelogram shape, a hexagon shape, etc.), since the area and spacing of the joints 80 can be changed simply by changing the overall length of the joints 80.

The waist elastic member 17 provided in the waist portion W is provided between the outer portion 18 and the inner portion 19 in the example shown in Figures 8 and 9, but as shown in Figures 10 and 11, it is provided between the first sheet 12S and the second sheet 12H in the inner portion 19, and the first sheet 12S and the second sheet 12H in the inner portion 19 may be welded via the waist elastic member 17 at the portion having the waist elastic member 17 (intersection portion) and directly at the portion not having the waist elastic member 17 (non-intersection portion). In this case, the joint 80 in the inner portion 19 may be continuous (the interval in the front-rear direction LD is zero) from the waist elastic member 17 closest to the waist opening WO to the waist elastic member 17 furthest from the waist opening WO as in the example shown in Figures 10 and 11, or may be intermittently arranged in the front-rear direction LD as in the example shown in Figures 8 and 9.

10 and 11, both the first sheet 12S and the second sheet 12H of the inner portion 19 extend to the same position in the front-to-rear direction LD at the waist lower portion U, but as long as both sheets extend further toward the leg opening LO than the waist elastic member 17 closest to the leg opening LO, one sheet (e.g., the first sheet 12S) may extend further toward the leg opening LO than the other sheet (not shown). In that case, the extended portion may have a trace similar to the joint 80 partially or entirely, or may not have any trace at all. As shown in Figures 10 and 11, when both the first sheet 12S and the second sheet 12H of the inner portion 19 extend to the lower waist portion U, the joints 80 of the first sheet 12S and the second sheet 12H may be provided in the same pattern as the inner portion 19 in the extended portion, but when the lower waist elastic member 15 is not provided in the extended portion as in the illustrated example, it is preferable that the joints 80 are intermittently arranged in the front-to-back direction LD at the joint position 90 via non-jointed portions 83, similar to the first portion P1.

In the example shown in Figures 10 and 11, the waist elastic member 17 is covered with an outer portion 18 formed by joining two layers, the first sheet 12S and the second sheet 12H, and the outer portion 18 has a smaller area of the joint 80 in the first portion P1 near the edge We of the waist opening WO, and the spacing of the joints 80 is the same or wider. This makes the outer surface of the first portion P1 soft to the touch, while preventing the first sheet 12S and the second sheet 12H from shifting when the edge We of the waist opening WO is formed by folding the first sheet 12S and the second sheet 12H, and when the product is worn.

In particular, the example shown in Figures 10 and 11 is preferable because the first sheet 12S and the second sheet 12H are used to form the exterior body 12F, 12B from the lower waist portion U to the inner portion 19 of the waist portion W, and the first sheet 12S and the second sheet 12H are welded at the above-mentioned joining position 90 with both the waist elastic member 17 and the lower waist elastic member 15 sandwiched between them, allowing the basic structure of the exterior body 12F, 12B to be constructed in a single welding process.

Other respects of the example shown in Figures 10 and 11 are similar to the example shown in Figures 8 and 9.

On the other hand, in order to improve manufacturing stability, it is better for the joint strength of all joints 80 to be equal. However, the joint strength of some joints 80 may be different from the joint strength of other joints 80, or the joint strength may vary within a single continuous joint 80 (joints 80 with different strengths may be continuous).

For example, as shown in the example of FIG. 12 and FIG. 13, when the area in the first portion P1 that is 10 mm or less from the edge We of the waist opening WO toward the leg opening LO is defined as the outer edge region Eo, and the area in the inner portion 19 that is 10 mm or less from the edge We of the waist opening WO toward the leg opening LO is defined as the inner edge region Ei, among the joints 80 located in the outer edge region Eo and the inner edge region Ei, one joint 80 is a strong joint 81 having a relatively high joint strength, and the other joints 80 are weak joints 82 having a relatively low joint strength, and it is preferable that the joints 80 located in the area of the first portion P1 excluding the outer edge region Eo and the area of the inner portion 19 excluding the inner edge region Ei are weak joints 82.

In this way, at the joining position 9080 across the outer edge region Eo and the inner edge region Ei, the strong joining portion 81 is located at one location, and the first sheet 12S and the second sheet 12H are firmly integrated near the folding position. This makes it easier to fold the first sheet 12S and the second sheet 12H when folding them to form the edge We of the waist opening WO, and also makes it difficult for the first sheet 12S and the second sheet 12H to shift at or near the edge We of the waist opening WO when doing so and when the product is worn. Moreover, in the first portion P1 and the inner portion 19, all of the joining portions 80 except for one strong joining portion 81 are weak joining portions 82, so flexibility is hardly lost.

Here, the strength of the joint 80 (joint strength) refers to the magnitude of the tensile force required to tear the joint 80 per unit area or unit length. The degree of strength of the joint can be determined as appropriate, but for example, it is preferable that the strong joint 81 is a film-like (more transparent than the surrounding area) in which almost all the fibers of the first sheet 12S and the second sheet 12H are melted and integrated (for example, less than 10 fibers may protrude). It is also preferable that the weak joint 82 is a film-like (more transparent than the surrounding area) in which some or all of the fibers located on the joint surface of the first sheet 12S and the second sheet 12H are welded, but some or all of the fibers on the opposite surface are not welded, and many fibers remain deformable.

The dimensions of the strong bond portion 81, the weak bond portion 82, and the non-bond portion 83 can be determined appropriately, but it is preferable that they are within the following ranges, for example.
Dimension of the strong joint 81 in the front-rear direction LD: 2 to 4 mm
Dimension of the weak joint 82 in the front-rear direction LD: 1.0 to 2.0 times the dimension of the strong joint 81 in the front-rear direction LD Dimension of the non-joined portion 83 in the front-rear direction LD: 0.5 to 1.2 times the dimension of the weak joint 82 in the front-rear direction LD

The thicknesses of the strong bond portion 81, the weak bond portion 82, and the non-bond portion 83 can be determined as appropriate, but are preferably within the following ranges, for example.
Apparent thickness of the weakly bonded portion 82: 0.5 to 0.9 times the sum of the apparent thickness of the first sheet 12S and the apparent thickness of the second sheet 12H in the non-bonded portion 83. Apparent thickness of the strongly bonded portion 81: 0.5 to 0.9 times the apparent thickness of the weakly bonded portion 82.

The strong joint 81 provided at one of the joining positions 90 across the outer edge region Eo and the inner edge region Ei can be provided in the outer edge region Eo, but providing it in the inner edge region Ei is preferable because it makes it particularly easy to fold the first sheet 12S and the second sheet 12H inward to form the edge We of the waist opening WO, and at that time and when the product is worn, the strong joint 81 is located in the inner part 19, making it difficult for the first sheet 12S and the second sheet 12H in the inner part 19 to shift at the edge We of the waist opening WO and its vicinity. In this case, the strong joint 81 provided in the inner edge region Ei is preferably within a range of 1 to 9 mm from the edge We of the waist opening toward the leg opening, and particularly preferably within a range of 2 to 8 mm. In addition, since the strong joint 81 is a thin and hard part, if it is provided in the inner edge region Ei, if the waist elastic member 17 and the strong joint 81 overlap, the feel on the wearer's skin is likely to deteriorate. Therefore, it is preferable that the strong joint 81 provided at one joining position 90 in the inner edge region Ei and the waist elastic member 17 located closest to the waist opening WO do not overlap as in the illustrated example. From this perspective, and from the perspective of sufficient shrinkage wrinkles being formed at the edge We of the waist opening WO, it is preferable that the distance in the front-to-back direction LD between the edge We of the waist opening WO and the waist elastic member 17 located closest to the waist opening WO is 0 to 5 mm. On the other hand, if the strong joint 81 is provided in the outer edge region Eo, it is preferable that the strong joint 81 be within a range of 0 to 5 mm from the edge We of the waist opening to the leg opening side.

In terms of flexibility, it is preferable that the second portion P2 does not have the strong joint 81, as in the first portion P1 except for the outer edge region Eo. However, if the entire waist portion W is flexible, the shape of the waist portion W may be deformed, which may deteriorate the fit and appearance. Therefore, as shown in the illustrated example, at the joining position 90 in the second portion P2, the strong joint 81 with a relatively high joining strength is preferably intermittently arranged in the front-rear direction LD via at least one of the weak joint 82 and the non-joint 83 with a relatively low joining strength. In this case, it is preferable that the strong joint 81 located closest to the waist opening WO side in the second portion P2 is located in the range from the position of the third waist elastic member 17 counting from the waist opening WO side to the position of the sixth waist elastic member 17, since the strong joint 81 improves rigidity and reduces the risk of the shape of the waist portion W being deformed, which may deteriorate the fit and appearance.

The strength of the joint in the lower waist portion U can be appropriately determined. For example, the entire portion can be a strong joint 81, or the portion having the lower waist elastic member 15 (intersection portion) can be a weak joint 82, and the other portion not having the lower waist elastic member 15 (non-intersection portion) can be a strong joint 81. One preferred example is similar to that described in Patent Document 2, in which at the joint position 90 in the lower waist portion U, strong joints 81 are adjacently arranged on both sides of the lower waist elastic member 15 in the front-to-back direction LD, and the portion between the adjacent strong joints 81 between the adjacent lower waist elastic members 15 is a weak joint 82. In this case, at the intersection portion between the joint position 90 and the lower waist elastic member 15, it is preferable that the weak joints 82 are formed as in the illustrated example, as long as the first sheet 12S and the second sheet 12H are welded to the lower waist elastic member 15, but the strong joints 81 may also be formed. In addition, if the arrangement of the strong joints 81 changes at the boundary between the waist lower part U and the waist part W, the texture will suddenly change, which may cause horizontal wrinkles to easily occur at the boundary or cause an uncomfortable feeling at the boundary. Therefore, as described above, it is preferable to provide strong joints 81 in the second part P2 as well, and to make the dimensions and spacing of the strong joints 81 at the joining position 90 of the second part P2 equal to the dimensions and spacing of the strong joints 81 located closest to the waist opening WO at the joining position 90 of the waist lower part U.

The waist elastic member 17 provided in the waist portion W is provided between the outer portion 18 and the inner portion 19 in the example shown in Figures 12 and 13, but as shown in Figures 14 and 15, it is provided between the first sheet 12S and the second sheet 12H in the inner portion 19, and the first sheet 12S and the second sheet 12H may be welded together via the waist elastic member 17 at the portion having the waist elastic member 17 (intersection portion) and directly at the portion not having the waist elastic member 17 (non-intersection portion). In the latter case, the inner edge region Ei has at least one waist elastic member 17, and at the joining position 90 in the inner portion 19, strong joining portions 81 with relatively high joining strength are arranged on both sides of the waist elastic member 17 in the front-to-back direction LD, and the portions between the adjacent strong joining portions 81 between the adjacent waist lower elastic members 15 are weak joining portions 82, and at the joining position 90 in the first portion P1 of the outer portion 18, the weak joining portions 82 are preferably arranged intermittently in the front-to-back direction LD via non-jointed portions 83.

14 and 15, both the first sheet 12S and the second sheet 12H of the inner portion 19 extend to the same position in the front-to-rear direction LD at the waist lower portion U, but as long as both sheets extend further toward the leg opening LO than the waist elastic member 17 closest to the leg opening LO, one sheet (e.g., the first sheet 12S) may extend further toward the leg opening LO than the other sheet (not shown). In that case, the extended portion may have traces similar to the strong bond portion 81 and the weak bond portion 82 partially or entirely, or may not have any traces at all. As shown in Figures 14 and 15, when both the first sheet 12S and the second sheet 12H of the inner portion 19 extend to the lower waist portion U, the joints 81, 82 of the first sheet 12S and the second sheet 12H may be provided in the extended portion in the same pattern as the inner portion 19, but when the lower waist elastic member 15 is not provided in the extended portion as in the illustrated example, it is preferable that the weak joints 82 are intermittently arranged in the front-to-back direction LD at the joint position 90 via the non-jointed portions 83, similar to the first portion P1.

In the example shown in Figures 14 and 15, the elastic member of the waist portion W is covered with an outer portion 18 formed by joining two layers, a first sheet 12S and a second sheet 12H, and the first portion P1 does not have a strong joint 81, and weak joints 82 are arranged intermittently in the front-to-back direction LD via non-joined portions 83 to integrate the first sheet 12S and the second sheet 12H. As a result, the outer surface feels soft against the skin, but the first sheet 12S and the second sheet 12H are less likely to slip when the first sheet 12S and the second sheet 12H are folded back to form the edge We of the waist opening WO and when the product is worn. In addition, by arranging the strong joint 81 in the inner portion 19, including the inner edge region Ei, the first sheet 12S and the second sheet 12H are firmly integrated near the folding position, so that the first sheet 12S and the second sheet 12H are easily folded to form the edge We of the waist opening WO, and at that time and when the product is worn, the first sheet 12S and the second sheet 12H are less likely to shift at or near the edge We of the waist opening WO.

In particular, the example shown in Figures 14 and 15 is preferable in that the first sheet 12S and the second sheet 12H are used to form the exterior body 12F, 12B from the lower waist portion U to the inner portion 19 of the waist portion W, and both the waist elastic member 17 and the lower waist elastic member 15 are sandwiched between the first sheet 12S and the second sheet 12H, and the first sheet 12S and the second sheet 12H are welded at the above-mentioned joining position 90, allowing the basic structure of the exterior body 12F, 12B to be constructed in a single welding process.

Other aspects of the example shown in Figures 14 and 15 can adopt the same structure as the example shown in Figures 12 and 13.

(Nonwoven cover)
In a pants-type disposable diaper with a two-piece exterior, the inner body 200 is exposed between the front outer body 12F and the rear outer body 12B, so it is preferable to have a cover nonwoven fabric 13 that covers the back surface of the inner body 200 from between the front outer body 12F and the inner body 200 to between the rear outer body 12B and the inner body 200 so that the liquid-impermeable sheet 11 is not exposed on the back surface of the inner body 200.

The nonwoven fabric used for the cover nonwoven fabric 13 is not particularly limited by the type of fiber or the method of bonding (intertwining) the fibers, and may be selected appropriately from the same material as the exterior bodies 12F, 12B, for example, but it is preferable to use an air-through nonwoven fabric, in which case the basis weight is preferably 20 to 40 g/m ² and the thickness is preferably 0.3 to 1.0 mm. The cover nonwoven fabric 13 may be a nonporous nonwoven fabric that does not have holes penetrating from the front to the back, or a perforated nonwoven fabric that has a large number of holes spaced apart from one another penetrating from the front to the back.

The front-rear range of the cover nonwoven fabric 13 is not particularly limited, and may extend in the front-rear direction LD over the entire area from the front end to the rear end of the inner body 200 as shown in Figs. 2 and 5, or may extend in the front-rear direction LD from the front-rear middle position of the area where the front exterior body 12F and the inner body 200 overlap to the front-rear middle position of the area where the rear exterior body 12B and the inner body 200 overlap as shown in Fig. 7. In addition, in the case of the example shown in Fig. 7, the front-rear length 13y of the overlapping portion between the cover nonwoven fabric 13 and the front exterior body 12F and the front-rear length 13y of the overlapping portion between the cover nonwoven fabric 13 and the rear exterior body 12B can be determined as appropriate, but usually can be about 20 to 40 mm each.

The width direction range of the cover nonwoven fabric 13 is set to a range that can hide the exposed back surface of the liquid-impermeable sheet 11. For this reason, in the illustrated example, since the liquid-impermeable sheet 11 is exposed between the base ends of the left and right rising gathers 60, the cover nonwoven fabric 13 is provided so as to cover at least the width direction range from the back side of the base end of one rising gather 60 to the back side of the base end of the other rising gather 60. This allows the liquid-impermeable sheet 11 to be concealed by the cover nonwoven fabric 13 and the gathered nonwoven fabric 62 of the rising gathers 60. In addition, even if the width direction ends of the cover nonwoven fabric 13 do not cover the back side of the base end of the rising gathers 60, but the gathered nonwoven fabric 62 covers the back side of the width direction ends of the cover nonwoven fabric 13, it is possible to conceal the liquid-impermeable sheet 11 by the cover nonwoven fabric 13 and the gathered nonwoven fabric 62. In this case, since both sides of the cover nonwoven fabric 13 are covered with the gathered nonwoven fabric 62, there is an advantage that both sides of the cover nonwoven fabric 13 are less likely to peel off from the liquid-impermeable sheet 11.

The inner and outer surfaces of the cover nonwoven fabric 13 can be bonded to the opposing surfaces via a hot melt adhesive. The fixed area of the cover nonwoven fabric 13 can be the entire front-rear direction and the entire width direction of the cover nonwoven fabric 13, or a part can be left unfixed. For example, if both ends in the width direction of the cover nonwoven fabric 13 are unfixed, the cover nonwoven fabric 13 is less susceptible to the influence of the rising gathers 60 even if the sides of the absorbent body 56 shrink somewhat, which has the advantage that wrinkles and folds are less likely to form in the cover nonwoven fabric 13. In this case, the width of the unfixed parts of both ends in the width direction of the cover nonwoven fabric 13 can be determined as appropriate, but can be, for example, 3 to 10 mm, preferably 5 to 8 mm.

(Interior joints)
The inner body 200 can be fixed to the outer bodies 12F, 12B by a joining means using material welding such as heat sealing or ultrasonic sealing, or by a hot melt adhesive. In the illustrated example, the inner body 200 is fixed to the inner surface of the outer bodies 12F, 12B via a hot melt adhesive applied to the back surface of the inner body 200, that is, in this case, the back surface of the liquid-impermeable sheet 11 and the root portion 65 of the rising gathers 60. The inner body joints 201, 202 that fix the inner body 200 and the outer bodies 12F, 12B can be provided in almost the entire overlapping area as shown in FIG. 2, and can also be provided in the portion excluding both ends in the width direction of the inner body 200, for example.

<Explanation of terms used in the specification>
As used herein, the following terms have the following meanings unless otherwise specified in the specification.

The "front-rear direction" refers to the direction indicated by the symbol LD in the figure (longitudinal direction), and the "width direction" refers to the direction indicated by the symbol WD in the figure (left-right direction), with the front-rear direction and the width direction being perpendicular to each other.

- "Front side" refers to the side closest to the wearer's skin when the pants-type disposable diaper is worn, and "back side" refers to the side furthest from the wearer's skin when the pants-type disposable diaper is worn.

- "Front surface" refers to the surface of the component that is closest to the wearer's skin when the pants-type disposable diaper is worn, and "back surface" refers to the surface that is farthest from the wearer's skin when the pants-type disposable diaper is worn.

"Elongation rate" refers to the value when the natural length is 100%. For example, an elongation rate of 200% is equivalent to an elongation ratio of 2 times.

- "Gel strength" is measured as follows. 1.0 g of superabsorbent polymer is added to 49.0 g of artificial urine (a mixture of urea: 2 wt%, sodium chloride: 0.8 wt%, calcium chloride dihydrate: 0.03 wt%, magnesium sulfate heptahydrate: 0.08 wt%, and ion-exchanged water: 97.09 wt%) and stirred with a stirrer. The resulting gel is left in a thermo-hygrostat at 40°C x 60% RH for 3 hours, then returned to room temperature, and the gel strength is measured with a curd meter (I.techno Engineering: Curdmeter-MAX ME-500).

・"Basis weight" is measured as follows. After pre-drying the sample or test piece, leave it in a test room or device under standard conditions (test location: temperature 23±1°C, relative humidity 50±2%) until it reaches a constant weight. Pre-drying refers to bringing the sample or test piece to a constant weight in an environment at a temperature of 100°C. Note that pre-drying is not necessary for fibers with an official moisture regain of 0.0%. Using a sample collection template (100mm x 100mm), cut out a sample measuring 100mm x 100mm from the test piece that has reached a constant weight. Measure the weight of the sample and multiply it by 100 to calculate the weight per square meter, which is the basis weight.

"Thickness" is automatically measured using an automatic thickness measuring device (KES-G5 handy compression measurement program) under the conditions of a load of 0.098 N/cm ² and a pressurized area of 2 cm ² .

- Water absorption is measured according to JIS K7223-1996 "Water absorption test method for superabsorbent resins."

The water absorption rate is the "time to the end point" when 2 g of superabsorbent polymer and 50 g of saline are used to perform the "water absorption rate test method for superabsorbent polymers" according to JIS K7224-1996.

- "Expanded state" means a flat, unfolded state without contraction (including any contraction, such as contraction due to elastic members) or sagging.

- Unless otherwise specified, the dimensions of each part refer to the dimensions in the unfolded state, not the natural length.

-If there is no description of the environmental conditions for a test or measurement, the test or measurement shall be performed in a test room or equipment under standard conditions (the test location shall be a temperature of 23±1°C and a relative humidity of 50±2%).

The present invention can be used for pants-type disposable wearable articles such as pants-type disposable diapers and pants-type sanitary napkins.

11...Liquid-impermeable sheet, 12A...Side seal, 12B...Rear exterior body, 12E...Waist extension portion, 12F, 12B...Exterior body, 12F...Front exterior body, 12H...Second sheet, 12S...First sheet, 13...Cover nonwoven fabric, 15...Lower waist elastic member, 17...Waist elastic member, 18...Outer portion, 19...Inner portion, 200...Interior body, 201, 202...Interior joint portion, 30...Top sheet, 40...Middle sheet, 50...Absorbent element, 56...Absorbent body, 58...Wrapping sheet, 60...Rising gather, 60A...Tip side portion, 60B...Attachment Root side portion, 62...gathered nonwoven fabric, 67...decummulated portion, 68...free portion, 80...joint portion, 81...strongly joined portion, 82...weakly joined portion, 83...non-joint portion, 90...joint position, 91...non-joint position, A1...non-stretchable region, A2...stretchable region, B...back body, C...buttocks cover portion, Ei...inner edge region, Eo...outer edge region, F...front body, HM...hot melt adhesive, L...middle region, LD...front-to-back direction, LO...leg opening, P1...first portion, P2...second portion, T...torso region, U...lower waist portion, W...waist portion, WD...width direction, WO...waist opening.