Absorbent article

Abstract

[Problem]To provide a free portion that has excellent posture stability on the inner side of a fixing portion of a rising gather. [Solution] The problem is solved by a rising gather 60 comprising: a root portion 65 positioned on the outer side in the width direction WD relative to a blocking position, and a body portion 66 extending inward in the width direction WD without being folded back from the root portion 65. The body portion 66 comprises a front end portion 67 and a rear end portion 69 each having a fixing portion BP fixed to a top sheet 30, and a non-fixed intermediate portion 68 not fixed to the top sheet 30. A gather elastic member 63 is attached to the tip end portion of the intermediate portion 68. Free portions FP, which are not fixed to the top sheet 30, are provided at an inner end portion in the width direction WD of the front end portion 67 and the rear end portion 69 so as to continue from the intermediate portion 68. Portions other than the free portions FP of the front end portion 67 and the rear end portion 69 form the fixing portions BP. The fixing portions BP are fixed to a waist expansion / contraction portion 15, and the boundaries between the free portions FP and the fixing portions BP are each located on an outer side surface in the width direction WD of a projection portion 16.

Description

absorbent articles

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

[0002] Currently, most absorbent articles such as disposable diapers and sanitary napkins have standing gathers (also called three-dimensional gathers) that rise from both sides of the width direction of the top sheet surface. The standing gathers prevent the lateral movement of excrement, thereby preventing so-called side leakage.

[0003] Many rising gathers have a root portion attached to the outside in the width direction of an imaginary line extending in the front-to-back direction along a cutoff position on both sides of the width direction of the top sheet surface, and a main portion extending from the inside edge in the width direction of the root portion, and the main portion has front and rear end portions with fixed portions fixed to the top sheet, and an intermediate portion located between the front and rear end portions and not fixed to the top sheet. These portions are formed from a gathered sheet such as a nonwoven fabric. Furthermore, at least the tip portion of the rising gather has a two-layer structure, and an elongated gathered elastic member is attached between the layers of at least the tip portion of the intermediate portion in a state stretched in the front-to-back direction (see, for example, Patent Document 1).

[0004] The middle portion contracts together with the gathered elastic members due to the contractile force of the gathered elastic members, and is also stretchable together with the gathered elastic members. When worn, the contractile force of the gathered elastic members shortens the front-to-back dimension of the tip of the middle portion, and because the middle portion is not fixed to the topsheet, the middle portion rises up so that it is higher as it approaches the tip (the part farthest from the base portion) and lower as it approaches the fixed parts at the front and rear ends.

[0005] Furthermore, in some absorbent articles such as tape-type disposable diapers, the main body of the rising gathers often extends inward in the width direction without being folded back from the base, and the tip of the main body often faces inward in the width direction.

[0006] In this type of inward-facing rising gather, the front and rear ends of the main body, which have the fixed parts, do not rise, and the middle part, which is closer to the fixed parts, generally has a lower rising height.

[0007] In contrast to this, as in the rising gathers described in Patent Document 2, when free sections that are not fixed to the top sheet are provided at the widthwise inner ends of the front and rear ends of the main body part so as to continue from the middle section, and the parts other than the free sections at the front and rear ends are fixed sections, the free sections rise up along with the middle section, so that the part of the middle section that is closer to the fixed section rises up higher than if there were no free section, and the free sections also function as leak prevention walls at the front and rear ends of the main body part.

[0008] However, the free portion described in Patent Document 2 leaves room for improvement in terms of stability in the standing up position.

[0009] JP 2023-43830 A JP 2023-004767 A

[0010] Therefore, a main object of the present invention is to provide an absorbent article having a free portion, which is excellent in stability of the upright posture, on the widthwise inner side of the fixed portion of the upright gather.

[0011] The absorbent article that solves the above-mentioned problems is as follows: <First aspect> An absorbent article comprising: an absorbent body, a liquid-permeable top sheet arranged on the outer side of the absorbent body, and rising gathers provided on both sides in the width direction of the surface of the top sheet, wherein the rising gathers have root portions attached to the outside in the width direction of an imaginary line continuing in the front-to-rear direction along blocking positions on both sides in the width direction of the surface of the top sheet, and a main body portion extending inward in the width direction from the inner edge in the width direction of the root portion without being folded back, wherein the main body portion has front and rear end portions having fixing portions fixed to the top sheet, and a middle portion located between the front and rear end portions and not fixed to the top sheet, wherein at least the tip of the middle portion is provided with a gathered stretchable portion having an elongated gathered elastic member extending along the front-to-rear direction, wherein the gathered stretchable portion is a portion that elastically stretches between a natural length state in which it is contracted in the front-to-rear direction together with the gathered elastic member and an expanded state in which it is stretched in the front-to-rear direction together with the gathered elastic member to a maximum elongation rate, an absorbent article characterized in that at least one of the front end and the rear end has a free portion that is not fixed to the top sheet over the entire front-to-back direction at the inner end in the width direction, and has the fixed portion adjacent to the outer side of the free portion in the width direction; the absorbent article has a waist stretchable portion adjacent to the back side of at least the free portion and the fixed portion on the outer side of the free portion in the width direction; the waist stretchable portion has a waist elastic member and is a portion that elastically stretches and contracts between a natural length state in which it contracts in the width direction together with the waist elastic member and has ridges extending in the front-to-back direction formed repeatedly in the width direction on the surface, and an expanded state in which it stretches in the width direction together with the waist elastic member to a maximum elongation rate and no longer has the ridges; the free portion is not fixed to the waist stretchable portion, and the fixed portion is fixed to the waist stretchable portion, and the boundary between the free portion and the fixed portion is located on the outer side of the ridges in the width direction.

[0012] (Effects) In this embodiment, when the rise-up gathers are stretched from their natural length to the state when worn, a bulge is present in the elastic waist section, the free section is not fixed to the elastic waist section, the fixed section is fixed to the elastic waist section, and the boundary between the free section and the fixed section is located on the outer side of the bulge in the width direction of the elastic waist section. This means that the free section tends to assume a rise-up position, extending upward along the outer side of the bulge in the width direction, and is supported by the inner bulge in the width direction, and the shape of the bulge is maintained by the contractile force of the waist elastic member, making it less likely to collapse inward in the width direction. Therefore, the free section of this rise-up gather provides greater stability in the rise-up position than conventional gathers.

[0013] <Second Aspect> The absorbent article of the first aspect, wherein the width of the free portion is 5 mm or more, the main body portion has a tip end region of a width equal to the width of the free portion, the gathered stretchable portion having a plurality of gathered elastic members spaced apart in the width direction, and the gathered elastic members are not provided outside the tip end region, the gathered stretchable portion extends across the intermediate portion and the free portion, and the front-to-back dimension of the portion of the gathered stretchable portion located within the free portion is 5 to 25% of the front-to-back dimension of the free portion.

[0014] (Effects) The width of the free portion can be determined as appropriate, but from the viewpoint of improving leak prevention performance, it is preferable that it be 5 mm or more. However, simply widening the width of the free portion may cause the free portion to become unstable in its upright position. Therefore, in such cases, it is preferable to have multiple gathered elastic members spaced apart in the width direction, and it is preferable that the gathered stretchable portion extend a sufficient length within the free portion.

[0015] <Third Aspect> The absorbent article of the first or second aspect, wherein the absorbent body spans the fixed portion of one of the rising gathers and the fixed portion of the other of the rising gathers, and the waist side edge of the absorbent body is located closer to the waist than the waist side end of the gather stretchable portion.

[0016] (Effects) When the absorbent body is arranged as in this embodiment, the rigidity of the absorbent body reduces the contraction in the width direction of the fixed portion, and the boundary between the free portion and the fixed portion is maintained further to the side, which makes it easier for the gathered elastic member to pull the free portion toward the intermediate portion, making the upright posture of the free portion more stable, which is preferable. Another advantage is that excreted liquid blocked by the free portion can be quickly absorbed.

[0017] <Fourth Aspect> The absorbent article of any one of the first to third aspects, wherein the front-to-back dimension of the portion of the free portion that overlaps with the waist stretchable portion is 50% or more of the front-to-back dimension of the free portion.

[0018] (Operation and Effect) The greater the overlap between the free portion and the elastic waist portion in the front-to-rear direction, the more stable the standing posture becomes, so it is preferable to configure it as in this embodiment.

[0019] <Fifth Aspect> The absorbent article of any one of the first to fourth aspects, wherein the top sheet has a plurality of convex portions provided at intervals on a surface of an area that overlaps with the free portion in an unfolded state, and the thickness of the convex portions in the area of ​​the top sheet that overlaps with the free portion is thicker than the thickness of the area of ​​the top sheet that overlaps with the fixed portion.

[0020] (Effects) In this embodiment, even if the free portion is not supported or is not fully supported by the raised portion of the waist elastic portion when worn, such as when the raised portion becomes lower to some extent due to the extension of the waist elastic portion when worn, the free portion is supported by the convex portion on the surface of the top sheet located inside the free portion in the width direction, further improving the stability of the free portion when standing up.

[0021] <Sixth Aspect> The absorbent article of the fifth aspect, wherein an area of ​​the top sheet that overlaps with the fixing part does not have the protrusions and has a constant thickness.

[0022] (Action and effect) The thickness difference described above can be produced by providing a convex portion in the area of ​​the top sheet that overlaps with the fixing portion, but by pressing and adhering the fixing portion to the top sheet so that the convex portion is crushed in the thickness direction, but it is more preferable to produce it by having the area of ​​the top sheet that overlaps with the fixing portion not have a convex portion and have a constant thickness.

[0023] <Seventh aspect> An absorbent body, a liquid-permeable top sheet arranged on the outer side of the absorbent body, and rising gathers provided on both sides in the width direction of the surface of the top sheet, wherein the rising gathers have a root portion attached to the outside in the width direction of an imaginary line continuing in the front-to-rear direction along blocking positions on both sides in the width direction of the surface of the top sheet, and a main body portion extending inward in the width direction from the inner edge in the width direction of the root portion without being folded back, wherein the main body portion has front and rear end portions having fixing portions fixed to the top sheet, and a middle portion located between the front and rear end portions and not fixed to the top sheet, wherein an elongated gathered elastic member extending along the front-to-rear direction is attached to at least the tip portion of the middle portion, wherein the middle portion contracts together with the gathered elastic member due to the contractile force of the gathered elastic member and is stretchable together with the gathered elastic member, an absorbent article characterized in that at least one of the front end portion and the rear end portion has a free portion that is not fixed to the top sheet over the entire front-to-rear direction at the inner end in the width direction, and has the fixed portion on the outside in the width direction of the free portion; the top sheet has a plurality of convex portions provided at intervals on the surface of an area that overlaps with the free portion in an unfolded state; and the thickness of the convex portions in the area of ​​the top sheet that overlaps with the free portion is thinner than the thickness of the area that overlaps with the fixed portion.

[0024] (Effects) In this embodiment, the free portion is supported by the convex portions on the top sheet surface located on the inner side in the width direction, and is therefore less likely to collapse inward in the width direction. Therefore, the free portion of the standing gathers in this embodiment provides better stability in the standing posture than conventional ones.

[0025] According to the present invention, an absorbent article is provided with a free portion, which is excellent in stability of the standing posture, on the widthwise inner side of the fixed portion of the standing gather.

[0026] 1 is a plan view showing the inner surface of the connectable disposable diaper in an unfolded state. 1 is a plan view showing the outer surface of the connectable disposable diaper in an unfolded state. 1 is a cross-sectional view taken along line 3-3 of FIG. 1. 1 is a cross-sectional view taken along line 4-4 of FIG. 1. 1 is a cross-sectional view taken along line 5-5 of FIG. 1. 1 is a cross-sectional view taken along line 6-6 of FIG. 1. 1 is a cross-sectional view taken along line 7-7 of FIG. 1. 1 is a cross-sectional view taken along line 8-8 of FIG. 1. 1 shows (a) a plan view in an unfolded state, (b) a cross-sectional view taken along line 9a-9a, and (c) a cross-sectional view taken along line 9b-9b, showing a stretch sheet. 1 is a cross-sectional view showing a main part including elastic waist sections and rising gathers. 1 is a cross-sectional view showing a main part including elastic waist sections and rising gathers. 1 is an enlarged plan view showing a main part of FIG. 1. 1 shows (a) a plan view in an unfolded state, (b) a cross-sectional view taken along line 9c-9c of the unfolded state, and (c) a cross-sectional view taken along line 9c-9c of the contracted state, showing a stretch sheet. 1 is a plan view showing a top sheet and an intermediate sheet in an unfolded state. 1 is an enlarged plan view of the top sheet and the intermediate sheet. 1 is an enlarged plan view of the top sheet and the intermediate sheet. 16(b) is a cross-sectional view showing the 1a-1a cross section, the 1b-1b cross section, and the 1c-1c cross section of FIG. 16(b). FIG.

[0027] Figures 1 to 8 show a connectable disposable diaper 10 (commonly referred to as a tape-type disposable diaper), an example of an absorbent article. The symbol X in the figures indicates the overall width of the diaper excluding the connecting tape 13, and the symbol L indicates the overall length of the diaper. Note that the dotted pattern in the cross-sectional view indicates an adhesive, such as a hot-melt adhesive, that joins the various components located on the front and back sides. However, this does not represent all adhesives, and adhesive can be applied to areas without the dotted pattern, as needed. The hot-melt adhesive can be applied by known methods, such as slot coating, continuous or dotted bead coating, spiral, Z-shaped, or wavy spray coating, or pattern coating (transfer of hot-melt adhesive using a relief printing method). Alternatively, or in addition, the hot-melt adhesive can be applied to the outer periphery of the elastic member to secure the elastic member to an adjacent member. Hot-melt adhesives include, for example, EVA-based, adhesive rubber-based (elastomer-based), polyolefin-based, and polyester / polyamide-based types, but no particular limitations apply. As a fixing or joining means for joining each component, material welding means such as heat sealing or ultrasonic sealing can also be used. In areas 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 using a hot melt adhesive, intermittent pattern coating such as a spiral, Z-shaped, or wavy pattern can be suitably used. When coating an area greater than the coating width of a single nozzle, intermittent pattern coating such as a spiral, Z-shaped, or wavy pattern can be performed with or without gaps in the width direction.

[0028] This connectable disposable diaper has a crotch region M including the center in the front-to-back direction LD, a ventral region F extending forward from the center in the front-to-back direction LD, and a dorsal region B extending rearward from the center in the front-to-back direction LD. This connectable disposable diaper also has an absorbent body 56 incorporated in a range including the crotch region M, a liquid-permeable top sheet 30 covering the front side of the absorbent body 56, a liquid-impermeable sheet 11 covering the back side of the absorbent body 56, and an exterior nonwoven fabric 12 covering the back side of the liquid-impermeable sheet 11 and constituting the outer surface of the product. When the absorbent body 56 has a constricted region 56n described below, the crotch region M refers to the region in the front-to-back direction LD including the constricted region 56n. When the absorbent body 56 does not have a constricted region 56n, the crotch region M refers to a region located at the center in the front-to-back direction LD and whose dimension in the front-to-back direction LD is 40% of the overall length of the product.

[0029] The materials and characteristic features of each part will be described below in order. The nonwoven fabric in the following description can be any known nonwoven fabric, 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 (e.g., polyethylene or polypropylene), polyesters, and polyamides (including single-component fibers and core-sheath and other composite fibers), regenerated fibers (e.g., rayon or cupra), and natural fibers (e.g., cotton), or a mixture of these. To enhance the flexibility of the nonwoven fabric, it is preferable to use crimped fibers as the constituent fibers. The constituent fibers of the nonwoven fabric can be hydrophilic fibers (including fibers made hydrophilic by a hydrophilizing agent), hydrophobic fibers, or water-repellent fibers (including fibers made water-repellent by a water-repellent agent). 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, and laminated nonwoven fabrics (including SMS nonwoven fabrics and SMMS nonwoven fabrics, which sandwich a meltblown layer between spunbond layers), depending on the fiber length, sheet formation method, fiber bonding method, and laminated structure. Any of these nonwoven fabrics can be used. (Absorbent Body) The absorbent body 56 is the part that absorbs and retains excretory fluid and can be formed from a fiber assembly. This fiber assembly can be made of stacked staple fibers such as cotton-like pulp and synthetic fibers, or a filament assembly obtained by opening a tow (fiber bundle) of synthetic fiber such as cellulose acetate as needed. When stacking cotton-like pulp or staple fibers, the fiber weight can be, for example, 100 to 300 g / m. ２ In the case of a filament aggregate, for example, 30 to 120 g / m ２The fineness of 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 aggregate, the filaments may be non-crimped fibers, but are preferably crimped fibers. The crimp degree of the crimped fibers can be, for example, 5 to 75, preferably 10 to 50, and more preferably 15 to 50, filaments per 2.54 cm. Uniformly crimped fibers can also be used.

[0030] The shape of the absorber 56 can be determined as appropriate. For example, the absorber 56 may be formed in a generally hourglass shape, with a narrowed portion 56n in which the portion located in the crotch region M is narrower than the front and rear sides, as in the illustrated example, or may be formed in any other appropriate shape, such as a rectangular shape. It is usually preferable that the absorber 56 be provided from the front to the rear of the crotch region, but this is not limitative.

[0031] (Superabsorbent Polymer Particles) The absorbent body 56 may contain superabsorbent polymer particles in part or in whole. Superabsorbent polymer particles include not only "particles" but also "powder." The superabsorbent polymer particles used in this type of absorbent article can be used as is. The particle size of the superabsorbent polymer particles is not particularly limited. For example, when the particles are sieved (shaken for 5 minutes) using a 500 μm standard sieve (JIS Z8801-1:2006) and the particles that fall through the sieve are then sieved (shaken for 5 minutes) using a 180 μm standard sieve (JIS Z8801-1:2006), the proportion of particles remaining on the 500 μm standard sieve is preferably 30% by weight or less, and the proportion of particles remaining on the 180 μm standard sieve is preferably 60% by weight or more.

[0032] The material for the superabsorbent polymer particles is not particularly limited, but one with a water absorption capacity of 40 g / g or more is preferred. Examples of superabsorbent polymer particles include starch-based, cellulose-based, and synthetic polymer-based materials, and examples 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 a commonly used powder-like shape, but other shapes can also be used.

[0033] The highly absorbent polymer particles preferably have a water absorption rate of 70 seconds or less, particularly 40 seconds or less. If the water absorption rate is too slow, the liquid supplied into the absorbent body 56 tends to flow back out of the absorbent body 56, which is known as backflow.

[0034] Furthermore, the highly absorbent polymer particles preferably have a gel strength of at least 1000 Pa. This effectively prevents the sticky feeling after absorbing liquid, even when the absorbent body 56 is bulky.

[0035] The basis weight of the highly absorbent polymer particles can be determined appropriately depending on the absorption amount required for the application of the absorbent body 56. Therefore, although it cannot be generalized, in general, it is 50 to 350 g / m ２ It can be said that:

[0036] (Wrapping Sheet) In order to prevent the superabsorbent polymer particles from escaping or to improve the shape retention of the absorbent body 56, the absorbent body 56 can be incorporated as an absorbent element 50 wrapped in a wrapping sheet 58. As the wrapping sheet 58, tissue paper, particularly crepe paper, nonwoven fabric, polylaminated nonwoven fabric, perforated sheet, etc. can be used. 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 SMMS (spunbond / meltblown / meltblown / spunbond) nonwoven fabric is particularly suitable, and polypropylene, polyethylene / polypropylene, etc. can be used as the material. The fiber weight is 5 to 40 g / m ２ , especially 10 to 30 g / m２ It is preferable that:

[0037] The packaging sheet 58 may be structured so that one sheet wraps the entire absorbent body 56, or multiple sheets, such as two sheets on top and two sheets on bottom, may wrap the entire absorbent body 56. The packaging sheet 58 may also be omitted.

[0038] (Top Sheet) The top sheet 30 is liquid permeable, and may be made of, for example, a perforated or non-perforated nonwoven fabric, a perforated plastic sheet, or the like.

[0039] The top sheet 30 preferably extends from the front end to the rear end of the product in the front-to-rear direction, but can be appropriately modified as needed. Also, as in the illustrated example, the top sheet 30 preferably extends in the width direction WD to the outside of the boundary between the main body portion 66 and the root portion 65 of the rising gathers 60 (described later), but can be appropriately modified as needed.

[0040] (Intermediate Sheet) In order to prevent backflow of liquid that has permeated the top sheet 30, an intermediate sheet 40 (also called a "second sheet") can be provided adjacent to the back side of the top sheet 30. The intermediate sheet 40 can also be omitted.

[0041] Various nonwoven fabrics can be suitably used as the intermediate sheet 40, and particularly, a bulky air-through nonwoven fabric is suitably used. For the air-through nonwoven fabric, composite fibers with a core-sheath structure are preferably used, 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 17 to 80 g / m ２ is preferred, and 25 to 60 g / m ２ The thickness of the raw material fibers of the nonwoven fabric is preferably 2.0 to 10 dtex. In order to make the nonwoven fabric bulky, it is also preferable to use eccentric fibers, hollow fibers, or eccentric and hollow fibers as all or part of the raw material fibers.

[0042] The intermediate sheet 40 may be positioned at the center and shorter than the width of the absorber 56, or may be positioned to cover the entire width of the absorber 56. The intermediate sheet may be provided over the entire length of the diaper, or may be provided only in the middle portion in the front-to-rear direction LD, such as in the crotch region M.

[0043] (Liquid-impermeable sheet) The liquid-impermeable sheet 11 is not particularly limited, but is preferably moisture-permeable. For example, a microporous sheet obtained by kneading an inorganic filler into a polyolefin resin such as polyethylene or polypropylene to form a sheet, and then stretching the sheet in a uniaxial or biaxial direction can be suitably used as the liquid-impermeable sheet 11. Furthermore, a liquid-impermeable sheet 11 having a nonwoven fabric base material and enhanced waterproofness can also be used.

[0044] The liquid-impermeable sheet 11 preferably has an extending portion that extends outward in the width direction WD beyond the top sheet 30. It is desirable that the liquid-impermeable sheet 11 extends over the same or a wider range than the absorbent body 56 in the front-to-rear direction LD and the width direction WD. The liquid-impermeable sheet 11 may be omitted.

[0045] (External Nonwoven Fabric) The external nonwoven fabric 12 covers the entire back side of the liquid-impermeable sheet 11, giving the outer surface of the product a cloth-like appearance. The nonwoven fabric can be used in one piece or in multiple pieces stacked together. In the latter case, it is preferable to bond the nonwoven fabrics together with a hot melt adhesive or the like. When a nonwoven fabric is used, the fineness of the constituent fibers is 1.0 to 6.0 dtex, and the basis weight is 15 to 45 g / m. ２ It is preferable that the thickness of the nonwoven fabric is 0.5 to 3.0 mm.

[0046] The exterior nonwoven fabric 12 may be replaced by a sheet other than a nonwoven fabric, or the exterior nonwoven fabric 12 may be omitted.

[0047] (End flap portions, side flap portions) The illustrated example of the connectable disposable diaper 10 has a pair of end flap portions EF that do not have the absorber 56 and extend to the front and rear of the absorber 56, respectively, and a pair of side flap portions SF that do not have the absorber 56 and extend laterally beyond both side edges of the absorber 56. The side flap portions SF may be made of a material (such as the gathered sheet 62, top sheet 30, liquid-impermeable sheet 11, and exterior nonwoven fabric 12) that is continuous with the portion that has the absorber 56, as in the illustrated example, or may be formed by attaching another material.

[0048] (Wing Portions) In the present connectable disposable diaper 10, the back portion B has wing portions WP that extend outward in the width direction WD beyond the crotch portion M. Similarly, the ventral portion F also has wing portions WP that extend outward in the width direction WD beyond the crotch portion M. These wing portions WP may be formed from a separate member from the other portions. However, in the illustrated example, in a structure having side flap portions SF, it is preferable to form narrowed side edges 10n from the side edges of the crotch portion M to the lower edges 10u of the wing portions WP by cutting away the middle of the sides of the side flap portions SF in the front-to-rear direction LD, as this facilitates manufacturing.

[0049] 1, 2 and 7, the wing portions WP of the back portion B are provided with connecting tapes 13 which are detachably connected to the outer surface of the abdominal portion F. When putting on the diaper 10, the connecting tapes 13 are wrapped around the outer surface of the abdominal portion F from both sides of the waist, and the connecting portions 13A of the connecting tapes 13 are connected to appropriate locations on the outer surface of the abdominal portion F.

[0050] As shown in FIG. 7 , the connecting tape 13 includes a base end 13C fixed to the wing portion WP, a sheet substrate forming a main portion 13B extending from the base end 13C, and a connecting portion 13A for the ventral portion F, which is provided in the middle of the main portion 13B in the width direction WD of the sheet substrate. The portion of the main portion 13B closer to the base end 13C than the connecting portion 13A is a non-connecting portion that is not connected to the ventral portion F. The side edges of the base end 13C may coincide with the side edges of the wing portion WP, or, as shown in the illustrated example, may be slightly spaced inward in the width direction WD from the side edges of the wing portion WP. The inner edges of the connecting portion 13A in the width direction may coincide with the side edges of the wing portion WP, but it is preferably sufficiently spaced outward in the width direction WD from the side edges of the wing portion WP, as shown in FIGS. 1 and 7 .

[0051] The connecting portion 13A may be provided with a hook material (male material) of a mechanical fastener (surface fastener) or with an adhesive layer. The hook material has many engaging protrusions on its connecting surface, and these engaging protrusions become entangled with fibers or the like on the target surface, thereby adhering to the target surface.

[0052] The sheet substrate forming the base end portion 13C to the main body portion 13B may be a nonwoven fabric, a plastic film, a polylaminated nonwoven fabric, paper, or a composite material thereof, and may have a fineness of 1.0 to 3.5 dtex and a basis weight of 60 to 100 g / m. ２ A spunbond nonwoven fabric, an air-through nonwoven fabric, or a spunlace nonwoven fabric having a thickness of 1 mm or less is preferred.

[0053] The connecting tape 13 may be such that at least a portion of the non-connected portion is stretchable in the width direction WD, or may be such that the entirety is not stretchable.

[0054] (Target portion) It is preferable that a target portion 12T be provided at the connection point of the connecting tape 13 in the abdominal portion F. As shown in the illustrated example, the target portion 12T can be provided by attaching a sheet material to the outer surface of the abdominal portion F to facilitate connection.

[0055] The sheet material for forming the target portion 12T is not particularly limited, but when the connecting portion 13A is a hook material, for example, a long-fiber nonwoven fabric in which the fibers are partially welded to each other by ultrasonic welding in an intermittent pattern can be used.

[0056] Furthermore, when the connecting portion 13A is a hook material, a composite sheet material can be used as the sheet material for forming the target portion 12T, in which a large number of loop threads are sewn onto the surface of a base material made of a plastic film or nonwoven fabric, so that the engaging protrusions of the hook material can become entangled.

[0057] Furthermore, when the connecting portion 13A is a hook material and the connecting portion of the connecting tape 13 in the ventral portion F is made of nonwoven fabric (for example, when an outer nonwoven fabric 12 is provided as in the illustrated example), it is possible to use an appropriate location of the outer nonwoven fabric 12 as the target portion 12T and connect the hook material by entangling it with the fibers of the outer nonwoven fabric 12 without adding a sheet material to form the target portion 12T.

[0058] On the other hand, when the connecting portion 13A is an adhesive layer, the target portion 12T can be a sheet material such as a plastic film with a smooth surface that has been subjected to a release treatment so as to have good adhesiveness with the adhesive layer.

[0059] (Rising Gathers) In order to block excrement moving laterally along the top sheet 30 and prevent so-called side leakage, rising gathers 60 are provided on both sides of the surface of the top sheet 30 in the width direction WD.

[0060] The raised gathers 60 in the illustrated example have a root portion 65 attached to the outside in the width direction WD of an imaginary line continuing in the front-to-back direction LD along blocking positions on both sides in the width direction WD of the surface of the top sheet 30, and a main body portion 66 extending inward in the width direction WD from the inner edge in the width direction WD of the root portion 65. The main body portion 66 also has a front end portion 67 and a rear end portion 69 having fixed portions BP fixed to the top sheet 30 (in other words, the range of the main body portion 66 in the front-to-back direction LD that has the fixed portions BP is the front end portion 67 and the rear end portion 69), and an intermediate portion 68 located between the front end portion 67 and the rear end portion 69 and not fixed to the top sheet 30, and at least the tip portion of the intermediate portion 68 is provided with a gathered stretchable portion having elongated gathered elastic members 63 extending along the front-to-back direction LD. The gathered stretchable portion 61 is the portion to which the contractile force of the gathered elastic member 63 acts, and is a portion that elastically stretches between a natural length state in which it is contracted in the front-to-back direction LD together with the gathered elastic member 63, and an expanded state in which it is stretched in the front-to-back direction LD together with the gathered elastic member 63 to the maximum elongation rate.

[0061] The main body portion 66 and the root portion 65 can be formed by a gathered sheet 62 that is folded in half at the tip of the main body portion 66 (the end opposite the root portion 65) to form a two-layer structure consisting of an inner layer 62n and an outer layer 62f. In this case, a gathered elastic member 63 can be provided between the inner layer 62n and the outer layer 62f. As shown in Figures 3 and 4, the inner layer 62n does not need to extend to the root portion 65, but may extend only to the middle position in the width direction WD of the main body portion 66. Alternatively, it may extend to the root portion 65 (not shown). In other words, the main body portion 66 may have a single layer on the root portion 65 side. The gathered sheet 62 may also have a layer structure of three or more layers, and may particularly include a liquid-impermeable film as an intermediate layer. When the gathered sheet 62 has a multi-layer structure, the number of layers may be increased without folding a single nonwoven fabric, or by adding another nonwoven fabric to the multi-layer structure by folding a single nonwoven fabric.

[0062] The root portion 65 in the illustrated example has a joining start point in the width direction WD on the side of the top sheet 30, and this joining start point passes through the blocking position and continues in the front-to-back direction LD. The root portion 65 in the illustrated example also has an extending portion that extends outward in the width direction WD beyond the top sheet 30, and this extending portion is joined with a hot melt adhesive or the like to the inner surface of each side flap portion SF, that is, in the illustrated example, to the side of the liquid-impermeable sheet 11 and the side of the exterior nonwoven fabric 12 located outward in the width direction WD.

[0063] Although both ends of the main body portion 66 in the front-to-rear direction LD are provided with fixed portions BP that are fixed to the surface of the top sheet 30, an intermediate portion 68 located between the front and rear fixed portions BP is not fixed to the surface of the top sheet 30. As a result, in the natural length state and when worn, the dimension of the tip of the intermediate portion 68 in the front-to-rear direction LD is shortened by the contractile force of the gathered elastic member 63, and because the intermediate portion 68 is not fixed to the top sheet 30, as shown in Figure 3, the intermediate portion 68 rises higher as it approaches the tip (the portion farthest from the base portion 65; the end) and at a shallower angle (lower tip height) as it approaches the fixed portions BP of the front end portion 67 and the rear end portion 69.

[0064] The type of gathered sheet 62 is not particularly limited, but in general, a water-repellent nonwoven fabric is used from the viewpoints of feel and liquid-blocking properties. In particular, a nonwoven fabric having a meltblown layer between spunbond layers (SMS nonwoven fabric, SMMS nonwoven fabric, SSMS nonwoven fabric, SSMMS nonwoven fabric) is suitable because it can achieve both feel and liquid-blocking properties. The nonwoven fabric can be used alone or in a stack of multiple sheets. In the latter case, it is preferable to bond the nonwoven fabrics together with a hot melt adhesive or the like.

[0065] The gathered elastic member 63 can be an elastic member such as rubber in the form of a thread, string, or strip. As shown in the figure, only one gathered elastic member 63 can be provided on each side, or multiple gathered elastic members can be provided on each side. The elongation percentage of the gathered elastic member 63 in the expanded state can be determined as appropriate, but is preferably approximately 150 to 250%, and more preferably 180 to 230%. When synthetic rubber thread such as spandex is used as the gathered elastic member 63, its thickness is preferably 300 to 700 dtex, and more preferably 400 to 500 dtex.

[0066] As shown in Figures 1, 4 and 12, the front end 67 and rear end 69 of the main body portion 66 have a free portion FP that is not fixed to the top sheet 30 over the entire front-to-back direction LD at the inner end in the width direction WD (i.e., continuing from the intermediate portion 68 to the waist side edge), and it is preferable that the main body portion 66 has a fixed portion BP adjacent to the outer side of the free portion FP in the width direction.

[0067] In such inward rising gathers 60, the free portion FP rises together with the intermediate portion 68 as shown in Figure 10, so that the portion of the intermediate portion 68 closer to the fixed portion BP rises higher than when there is no free portion FP, and the free portion FP also functions as a leakage prevention wall at the front end 67 and rear end 69 of the main body portion 66.

[0068] The dimensions of the free portion FP can be determined as appropriate. The width x1 of the free portion FP is preferably 1 / 6 to 1 / 3 of the width x2 of the intermediate portion 68, and particularly preferably 2 / 11 to 1 / 4. More specifically, the lower limit of the width x1 of the free portion FP is preferably 5 mm or greater. Furthermore, if both the front end 67 and the rear end 69 have free portions FP, the width x1 of the free portion FP of the front end 67 and the width x1 of the free portion FP of the rear end 69 may be equal. However, because the range of motion of the legs is greater in the front than in the rear, it is also preferable to make the width x1 of the free portion FP of the front end 67 of the main body 66 wider (e.g., 1.2 to 1.5 times) than the width x1 of the free portion FP of the rear end 69. While the width x1 of the free portion FP is constant in the illustrated example, it may vary depending on the position in the front-to-rear direction LD, in which case it represents the minimum value. Although the width x2 of the intermediate portion 68 is constant in the illustrated example, it may vary depending on the position in the front-rear direction LD, in which case it means the maximum value.

[0069] As shown in the example, it is preferable that the free portion FP is provided at both the front end 67 and the rear end 69 of the main body portion 66, but it may also be provided at only the front end 67 or only the rear end 69.

[0070] Unlike the illustrated example, the gathered elastic member 63 can be provided in locations other than the tip of the intermediate portion 68. In particular, as in the illustrated example, it is preferable to provide the gathered elastic member 63 only in a tip-side region having a width equal to the width x1 of the free portion FP and not have any gathered elastic member 63 in any region other than the tip-side region, as this stabilizes not only the intermediate portion 68 but also the upright posture of the free portion FP. When the gathered elastic member 63 is provided only in a tip-side region having a width equal to the width x1 of the free portion FP, only one gathered elastic member 63 may be provided, but it is preferable to provide multiple gathered elastic members spaced apart in the width direction WD as in the illustrated example, and it is particularly preferable to have at least one gathered elastic member closer to the fixed portion BP and at least one gathered elastic member closer to the tip of the free portion FP in the width direction WD.

[0071] The gather stretchable portion 61 and the gather elastic member 63 may or may not extend to the free portion FP. In the former case, the portion of the gather elastic member 63 located in the free portion FP may be fixed to the free portion FP, and the gather stretchable portion 61 may extend across the intermediate portion 68 and into the free portion FP, or the portion of the gather elastic member 63 located in the free portion FP may not be fixed to the free portion FP, and the gather stretchable portion 61 may not be present in the free portion FP.

[0072] (Side Plane Gathers) Side elastic members 64 may be provided on the outside of the blocking position in the width direction WD of each side flap portion SF, and the leg-surrounding portions of each side flap portion SF may contract together with the side elastic members 64 due to the contractile force of the side elastic members 64, and may also be stretchable together with the side elastic members 64 (so-called planar gathers may be formed). The side elastic members 64 may also be omitted.

[0073] 1 and 9, the back portion B is provided with a waist stretchable portion 15 that extends along the width direction WD to cover the rear side of the fixed portion BP adjacent to the free portion FP of one of the rising gathers 60 and the rear side of the fixed portion BP adjacent to the free portion FP of the other of the rising gathers 60. The waist stretchable portion 15 has waist elastic members 72 and is a portion that elastically stretches between a natural length state (see FIG. 10) in which it contracts in the width direction WD together with the waist elastic members 72 to form ridges 16 on its surface that extend in the front-to-back direction LD repeatedly in the width direction WD, and a deployed state in which it stretches in the width direction WD together with the waist elastic members 72 to a maximum stretch rate and no ridges 16 remain. Therefore, the ridges 16 exist in a stretched state that is approximately the same as when the garment is worn (for example, a stretch rate range of approximately 100 to 130% in the width direction WD). The stretch rate of the waist stretchable section 15 in the expanded state can be determined as appropriate, but may be, for example, 180 to 300%.

[0074] As long as the waist stretchable portions 15 are adjacent to the backside of the free portion FP and the fixed portion BP on the outer side of the free portion FP in the width direction WD, unlike the illustrated example, one waist stretchable portion 15 adjacent to the backside of the free portion FP of one standing gather 60 in the width direction WD and the fixed portion BP on the outer side of the free portion FP in the width direction WD of the other standing gather 60, and the other waist stretchable portion 15 adjacent to the backside of the free portion FP of the other standing gather 60 and the fixed portion BP on the outer side of the free portion FP in the width direction WD of the other standing gather 60 may be provided separately with an interval in the width direction WD. Furthermore, the waist stretchable portions 15 may extend laterally beyond the fixed portion BP on the outer side of the free portion FP in the width direction WD, for example to the base portion 65, or they may only extend to the fixed portion BP on the outer side of the free portion FP in the width direction WD.

[0075] As shown in Figure 10, when the waist elasticized section 15 is stretched from its natural length to the state required for wearing, the raised portion 16 is present in the waist elasticized section 15, the free portion FP is not fixed to the waist elasticized section 15, and the fixed portion BP is fixed to the waist elasticized section 15. The boundary Q between the free portion FP and the fixed portion BP is located on the outer side of the raised portion 16 in the width direction WD of the waist elasticized section 15. This means that the free portion FP tends to rise upward along the outer side of the raised portion 16 in the width direction WD. Supported by the raised portion 16 located on the inner side in the width direction WD, and the shape of the raised portion 16 maintained by the contractile force of the waist elastic member 72, the free portion FP of such raised gathers 60 is less likely to collapse inward in the width direction WD. Therefore, the raised portion FP of such raised gathers 60 has superior stability in its raised position compared to conventional structures. From the perspective of improving leakage prevention, the widthwise dimension x1 of the free portion FP is preferably 5 mm or greater, and posture stability is particularly important for such wide free portions FP.

[0076] The waist stretchable section 15 has no size limitation in the front-to-back direction LD, as long as it extends in the width direction WD to encompass the free section FP and the fixed section BP on the outside of the free section FP in the width direction WD. Therefore, the dimension FPo in the front-to-back direction LD of the part of the free section FP that overlaps with the waist stretchable section 15 can be determined as appropriate, but since the greater the overlap between the free section FP and the waist stretchable section 15 in the front-to-back direction LD, the greater the stability in the upright posture. Therefore, it is preferable that the dimension FPo in the front-to-back direction LD of the part of the free section FP that overlaps with the waist stretchable section 15 be 50% or more of the dimension FPy in the front-to-back direction LD of the free section FP.

[0077] The positional relationship between the waist elastic portion 15 and the free portion FP can be determined as appropriate. The entire waist elastic portion 15 may be located closer to the waist than the boundary between the free portion FP and the intermediate portion 68, or a portion of the waist elastic portion 15 may overlap the intermediate portion 68. In the former case, the dimension 15y in the front-to-back direction LD of the waist elastic portion 15 may be approximately 60 to 90% of the dimension FPy in the front-to-back direction LD of the free portion FP. As shown in the example, the dimension 15y in the front-to-back direction LD of the waist elastic portion 15 overlapping the free portion FP is preferably longer (e.g., approximately 1.5 to 4.0 times longer) than the minimum dimension 15m in the front-to-back direction LD of the waist elastic portion 15 located between the two rising gathers 60 in the unfolded state. However, the dimension 15y in the front-to-back direction LD of the waist elastic portion 15 may be constant.

[0078] Instead of or in addition to providing the elastic waist section 15 on the back section, the elastic waist section 15 can be provided on the ventral section F.

[0079] The waist elastic member 72 may be elongated (e.g., thread-like or string-like), or may be non-perforated or perforated film-like, mesh-like, or other suitable shape. The waist elastic member 72 is fixed to the components constituting the waist elastic portion 15. For example, when using the elongated waist elastic member 72 shown in the figure, as shown in FIGS. 9 and 13 , two support sheet layers 71 such as nonwoven fabrics are joined together with an adhesive such as a hot melt adhesive or by ultrasonic welding, and the waist elastic member 72 is fixed between the two support sheet layers 71 in a stretched state in the width direction WD to form a stretchable sheet 70. The stretchable sheet 70 is then fixed to a component behind the rising gathers 60 in a stretched state in the width direction WD, thereby forming the waist elastic portion 15. Approximately 5 to 15 elongated waist elastic members 72 with a thickness of 420 to 1120 dtex can be provided at intervals of 3 to 10 mm, and the stretchability of the fixed members can be approximately 150 to 250%. In the example stretch sheet 70 shown in Figure 9, two support sheet layers 71 are continuously joined in the width direction WD, and waist elastic members 72 are continuously fixed in the width direction WD at the joint positions. However, as shown in Figure 13, two support sheet layers 71 can also be intermittently joined in the width direction WD, and waist elastic members 72 can be fixed to the support sheet layers 71 only at the joint positions.

[0080] Both ends of the stretch sheet 70 in the width direction WD may be non-stretchable regions 76 so that they can be held and attached by suction during manufacturing. In other words, the entire stretch sheet 70 does not have to form the waist stretch section 15. The non-stretchable region 76 may be a region without waist elastic members 72, but the elastic members 72 may be arranged across the intermediate stretchable region 75 and the non-stretchable region 76, and the elastic members 72 may be cut or left unfixed in the non-stretchable region 76, so that although the elastic members 72 remain in the non-stretchable region 76, there is little or no stretch.

[0081] Furthermore, by providing a non-elastic region 77 that has no waist elastic member 72 or that has the waist elastic member 72 cut off and therefore has little or no stretch, on one side in the front-to-back direction LD (the crotch side in the illustrated example) of the stretch sheet 70 in the unfolded state, of the portion that is located between both the rising gathers 60, as described above, the dimension in the front-to-back direction LD of the waist stretchable portion 15 in the portion that overlaps with the free portion FP can be made longer than the dimension in the front-to-back direction LD of the waist stretchable portion 15 that is located between both the rising gathers 60 in the unfolded state. Furthermore, by providing a similar non-elastic region 77 in the stretch sheet 70 throughout the entire front-to-back direction LD at the middle of the width direction WD, it is possible to provide independent waist stretchable portions 15 on both sides in the width direction WD.

[0082] In the illustrated example, the stretch sheet 70 is disposed between the liquid-impermeable sheet 11 and the absorbent element 50, but this arrangement is not particularly limited. For example, the stretch sheet 70 may be disposed between the liquid-impermeable sheet 11 and the exterior nonwoven fabric 12, or may be provided on the outside of the exterior nonwoven fabric 12. These arrangements also apply when the waist elastic members 72 are disposed independently of the stretch sheet 70 rather than being incorporated into the stretch sheet 70.

[0083] The waist elastic portion 15 may have any known structure, as long as it is elastically stretchable between a natural length state in which it contracts in the width direction WD together with the waist elastic members 72, forming repeated ridges 16 extending in the front-to-back direction LD on the surface, and a fully extended state in which it stretches in the width direction WD together with the waist elastic members 72 to a maximum elongation rate, eliminating the ridges 16. For example, as shown in Figures 9(b) and 9(c), the front and back members of the waist elastic members 72 are continuously joined in the width direction WD, so that in the contracted state, the cross section of the waist elastic portion 15 along the width direction WD becomes wavy, as shown in Figure 10 (first elastic structure). As a result, the front and back surfaces of the waist elastic portion 15 are repeatedly formed with ridges 16 extending in the front-to-back direction LD in the width direction WD. In this case, it is sufficient that the waist elastic members 72 are fixed to the front and back members of the support sheet at least at both ends of the waist elastic portion 15 in the width direction WD, but as in the illustrated example, the waist elastic members 72 may be fixed to the front and back members over the entire width direction WD, thereby joining the front and back members and fixing the waist elastic member 72 to the front and back members. The front and back members of the waist elastic members 72 are not limited as long as they are located on the front and back sides of the waist elastic member 72, respectively. In the illustrated example, the front members of the waist elastic members 72 are the support sheet layer 71, absorbent element 50, top sheet 30, and gathered sheet 62, and the back members of the waist elastic members 72 are the support sheet layer 71, liquid impermeable sheet 11, and exterior nonwoven fabric 12.

[0084] Alternatively, as shown in Figure 13, the front and back members of the waist elastic member 72 may be intermittently joined in the width direction WD, with the waist elastic member 72 secured to the front and back members at the joints 74. In this case, the front and back members are always held together at the joints 74, while the front and back members are separated from each other in the contracted state at the non-jointed areas 73 between adjacent joints 74, forming pleats (a second stretchable structure). As a result, although not shown, raised portions extending in the front-to-back direction LD are repeatedly formed in the width direction WD on the front and back surfaces of the waist stretchable portion 15. Note that while Figure 13 only shows the stretchable sheet 70, the absorbent element 50, top sheet 30, and gathered sheet 62 may be joined continuously to the front side in the width direction WD, and the liquid-impermeable sheet 11 and exterior nonwoven fabric 12 may be joined continuously to the back side.

[0085] In the second stretchable structure, the position of the raised portion 16 is determined at the non-jointed portion 73 between the front and back members of the waist elastic member 72. Therefore, the root portion 65 and the fixed portion BP of the rising gathers 60 can be fixed to the opposing surfaces so that the boundary Q between the free portion FP and the fixed portion BP is located outside the non-jointed portion 73 in the width direction WD. On the other hand, in the first stretchable structure, the raised portion 16 is automatically formed at the boundary Q between the free portion FP and the fixed portion BP of the rising gathers 60 where the rigidity changes (because the number of bonded sheets stacked inside the boundary in the width direction WD is less than the number of bonded sheets stacked outside the boundary in the width direction WD, the rigidity of the former portion is lower than the rigidity of the latter portion), and the boundary Q between the free portion FP and the fixed portion BP is located on the outer side surface of the raised portion 16 in the width direction WD. Therefore, in this case, it is not necessary to position the root portion 65 and the fixed portion BP of the rising gathers 60 relative to the raised portion 16.

[0086] As shown in the illustrated example, the absorber 56 spans the fixed portion BP of one rising gather 60 and the fixed portion BP of the other rising gather 60, and if the waist-side edge of the absorber 56 is located closer to the waist than the waist-side end of the gather stretchable portion 61, the rigidity of the absorber 56 reduces contraction of the fixed portion BP in the width direction WD caused by the waist stretchable portion 15, and the boundary between the free portion FP and the fixed portion BP is maintained more to the side, making it easier for the gather elastic member 63 to exert a force pulling the free portion FP toward the intermediate portion 68, and making the rising posture of the free portion FP more stable, which is preferable. Another advantage is that excreted liquid blocked by the free portion FP can be quickly absorbed.

[0087] On the other hand, the top sheet 30 may have a constant thickness, but it is preferable that the top sheet 30 has a plurality of spaced convex portions 31 on the surface in an area that overlaps with the free portion FP in the unfolded state, and that the thickness 31t (apparent thickness, maximum value) of the convex portions 31 in the area of ​​the top sheet 30 that overlaps with the free portion FP is thicker than the thickness (apparent thickness, maximum value) of the area that overlaps with the fixed portion BP. As a result, even if the free portion FP is not supported or is not fully supported by the convex portions 16 of the waist elastic portion 15, for example, if the convex portions 16 are lowered to some extent due to extension of the waist elastic portion 15 when worn, as shown in Figure 11, the free portion FP is supported by the convex portions 31 on the surface of the top sheet 30 that are located inside the free portion FP in the width direction WD, further improving the stability of the free portion FP in an upright position. As can be seen from this effect, when there is no waist stretch section 15, or even if there is one, the boundary between the free section FP and the fixed section BP is not located on the outer side of the raised section 16 in the width direction WD, if the free section FP is supported by the convex section 31 of the top sheet 30, the posture stability of the free section FP will be improved even if the free section FP is not supported by the raised section 16.

[0088] The difference between the thickness 31t of the convex portion 31 in the region of the top sheet 30 that overlaps with the free portion FP and the thickness of the region that overlaps with the fixed portion BP can be appropriately determined, and can be, for example, 0.1 to 0.5 mm.

[0089] The difference in thickness described above can be produced by having a constant thickness and no convex portion 31 in the area of ​​the top sheet 30 that overlaps with the fixing portion BP, as shown in Figure 14, or by providing a convex portion 31 in the area of ​​the top sheet 30 that overlaps with the fixing portion BP, as shown in Figure 18, and pressing and adhering the fixing portion BP to the top sheet 30 so that the convex portion 31 is crushed in the thickness direction.

[0090] The structure of the protrusions 31 provided on the surface of the top sheet 30 is not particularly limited, and may be solid protrusions 31 with no recesses on the backside of the protrusions 31, or may have recesses on the backside of the protrusions 31 as in the examples shown in Figures 14 to 18. Furthermore, the protrusions 31 may be ridge-shaped protrusions 31 that are continuous in the front-to-rear direction LD or the width direction WD.

[0091] To explain the protrusions 31 in the example shown in Figures 14 to 18 in more detail, the protrusions 31 are formed by extruding part of the top sheet 30 from the back side to the front side by embossing. A large number of the protrusions 31 are arranged at intervals in both the width direction WD and the front-to-back direction LD. This arrangement can be modified as appropriate, such as in a matrix as shown in Figure 15 or in a staggered pattern (adjacent rows are staggered) as shown in Figures 14 and 16.

[0092] The dimensions of the protrusions 31 can be determined as appropriate. As shown in Figures 14 to 16, the longitudinal (LD) dimension 31m of the protrusions 31 is set to be equal to or less than the center-to-center distance 80y between a joint 80 (described below) located on one side of the protrusions 31 in the longitudinal direction LD and a joint 80 located on the other side. The lower limit is preferably about 0.9 times the center-to-center distance 80y, and for infant use, it is preferably about 2.7 to 9 mm. Similarly, the widthwise (WD) dimension 31c of the protrusions 31 is set to be equal to or less than the center-to-center distance 80x between a joint 80 located on one side of the protrusions 31 in the widthwise direction WD and a joint 80 located on the other side. The lower limit is preferably about 0.9 times the center-to-center distance 80y, and for infant use, it is preferably about 2.7 to 9 mm. Furthermore, the height 31z of the protrusions 31 is preferably equal to or less than the center-to-center distance 80x between a joint 80 located on one side of the protrusions 31 in the widthwise direction WD and a joint 80 located on the other side. The lower limit is preferably about 0.9 times the center-to-center distance 80y, and for infant use, it is preferably about 2.7 to 9 mm.

[0093] The arrangement intervals of the protrusions 31 can be determined as appropriate, but for use with infants, in the case of a matrix arrangement as shown in Fig. 15, it is preferable that the center-to-center spacing 31x in the width direction WD between rows of protrusions 31 adjacent in the width direction WD in the front-to-rear direction LD is about 3 to 10 mm, and the center-to-center spacing 31y in the width direction WD between rows of protrusions 31 adjacent in the front-to-rear direction LD is about 3 to 10 mm. Also, in the case of a staggered arrangement as shown in Fig. 16, it is preferable that the center-to-center spacing 31x in the width direction WD between rows of protrusions 31 adjacent in the width direction WD in the front-to-rear direction LD is about 3 to 10 mm, and the center-to-center spacing 31y in the width direction WD between rows of protrusions 31 adjacent in the front-to-rear direction LD is about 3 to 10 mm.

[0094] The shape of the protrusions 31 is preferably a circular dome shape, but it can also be an elliptical dome shape or a regular polygonal dome shape. Note that, because the protrusions 31 are formed by extruding the top sheet 30 by embossing, the desired shape can be obtained by appropriately changing the shape of the protrusions used in the processing.

[0095] (Joints) As shown in Figures 14 to 18, it is preferable that the portions of the top sheet 30 between adjacent convex portions 31 in the width direction WD and the front-to-back direction LD are joined to the intermediate sheet 40 by pressure welding, thereby forming a large number of joints 80 in an intermittent joining pattern in the width direction WD and the front-to-back direction LD, as this provides excellent shape retention for the convex portions 31. As mentioned above, when the convex portions 31 are provided not only in the area of ​​the top sheet 30 that overlaps with the free portion FP but also in the area that overlaps with the fixed portion BP, as shown in Figures 14 and 18, the intermediate sheet 40 is not extended laterally to the position that overlaps with the fixed portion BP (i.e., the side edge of the intermediate sheet is positioned closer to the center in the width direction WD than the boundary between the free portion FP and the fixed portion BP), or, although not shown, the intermediate sheet 40 is extended laterally to the position that overlaps with the fixed portion BP, but no joint portion 80 is provided in the area that overlaps with the fixed portion BP, thereby making it possible to make the convex portions 31 that overlap with the free portion FP less likely to be crushed and the convex portions 31 that overlap with the fixed portion BP more likely to be crushed.

[0096] Furthermore, in the region between adjacent convex portions 31 in the front-to-rear direction LD, it is preferable that a plurality of rows of joints 80 spaced apart in the width direction WD are formed across the center of the region in the width direction WD, and that the top sheet 30 and the intermediate sheet 40 are not welded in the gaps in the width direction WD between the joints 80, forming compressed regions 81 in which the top sheet 30 is compressed more than on both sides of the top sheet 30 in the front-to-rear direction LD. As long as the top sheet 30 is compressed in the compressed regions 81, the intermediate sheet 40 may or may not be compressed integrally with the top sheet 30. Furthermore, in the regions other than the joints 80 and compressed regions 81, the top sheet 30 and the intermediate sheet 40 may not be welded and may be compressed similarly to the gaps in the width direction WD; however, it is preferable that the top sheet 30 and the intermediate sheet 40 are not welded and the top sheet 30 is less compressed than in the gaps in the width direction WD (including not being compressed at all). In other words, when the thickness of the joint portion 80 in the top sheet 30 is T1, the thickness of the compressed portion 81 is T2, and the thickness of the portion other than the joint portion 80 and the compressed portion 81 is T3, it is acceptable for T1 < T2 = T3, but it is preferable that T1 < T2 < T3.

[0097] The joining pattern may be a pattern in which a joining portion 80 is formed at the center position in the width direction WD corresponding to the center position in the width direction WD of the convex portion 31 adjacent to the front-to-rear direction LD, as shown in Figures 15(b) and 16(a), or a pattern in which a joining portion 80 is not formed at the center position in the width direction WD, as shown in Figures 15(b) and 16(a).

[0098] As shown in Fig. 15, a single row of joint portions 80 arranged at intervals in the width direction WD can be provided in the region between adjacent protrusions 31 in the front-rear direction LD, or multiple rows of joint portions 80 can be provided at intervals in the front-rear direction LD as shown in Fig. 16. The former is suitable for a pattern in which the protrusions 31 are arranged in a matrix, such as the form shown in Fig. 15, in which the protrusions 31 are arranged in a matrix, with the intervals in the front-rear direction LD being narrow, while the latter is suitable for a pattern in which the protrusions 31 are arranged in a staggered pattern, such as the form shown in Fig. 16, in which the protrusions 31 are arranged in a staggered pattern, with the intervals in the front-rear direction LD being wide.

[0099] The shape of each joint 80 is not particularly limited, and may be any shape such as a circle as shown in the example, an ellipse, a polygon, a star, or a cloud.

[0100] The dimensions of the joints 80 can be determined as appropriate, but preferably, the individual joints 80 between adjacent protrusions 31 in the front-to-rear direction LD are point joints with a front-to-rear direction LD length 80m of approximately 0.1 to 0.4 times the center-to-center distance 31y in the width direction WD of the row of adjacent protrusions 31 in the front-to-rear direction LD (e.g., 0.5 to 3 mm for infant use), and a width direction WD length 80c of approximately 0.1 to 0.4 times the center-to-center distance 31x in the width direction WD of the row of adjacent protrusions 31 in the width direction WD (e.g., 0.5 to 3 mm for infant use). Furthermore, the width direction WD spacing 80d between adjacent joints 80 in the width direction WD is preferably approximately 1 to 5 times the width direction WD length 80c of the joints 80 (e.g., 0.5 to 15 mm for infant use), and the number of joints 80 in the width direction WD row is preferably approximately 2 to 4.

[0101] On the other hand, as shown in Fig. 16 , when the protrusions 31 are staggered, the spaces between adjacent protrusions 31 in the width direction WD are also the spaces between adjacent protrusions 31 in the front-rear direction LD, so that joints 80 similar to those between adjacent protrusions 31 in the front-rear direction LD are provided, whereas as shown in Fig. 15 , when the protrusions 31 are arranged in a matrix, in addition to the joints 80 between adjacent protrusions 31 in the front-rear direction LD, joints 80 are also provided intermittently in the front-rear direction LD between adjacent protrusions 31 in the width direction WD. The pattern of the joints 80 between adjacent protrusions 31 in the width direction WD is not particularly limited, but it is preferable to arrange dot-like joints 80 at intervals in the front-rear direction LD, and compressed portions 81 can be formed in the spaces in the front-rear direction LD as in the spaces in the width direction WD, as shown in Fig. 15(b) . The row of joints 80 in the front-rear direction LD may be provided in a single row at the midpoint of adjacent protrusions 31 in the width direction WD as in the illustrated example, or multiple rows may be provided at intervals in the width direction WD. The dimensions of the point-like joints 80 are not particularly limited, but it is preferable that the length 80m in the front-rear direction LD is approximately 0.1 to 0.4 times the center-to-center spacing 31y in the front-rear direction LD of the row of protrusions 31 adjacent in the front-rear direction LD (e.g., 0.5 to 3 mm for use with infants), and the length 80c in the width direction WD is approximately 0.1 to 0.4 times the center-to-center spacing 31x in the width direction WD of the row of protrusions 31 adjacent in the width direction WD (e.g., 0.5 to 3 mm for use with infants).

[0102] The joining range A4 in the width direction WD by each joint 80 between adjacent protrusions 31 in the front-to-rear direction LD can be determined as appropriate, and can be, for example, about 0.3 to 1 times (for infants, for example, 1 to 10 mm) the center-to-center spacing 31x in the width direction WD of the row of protrusions 31 adjacent in the width direction WD in the front-to-rear direction LD. Furthermore, the joining range A3 in the front-to-rear direction LD by each joint 80 between adjacent protrusions 31 in the width direction WD can be determined as appropriate, and can be, for example, about 0.3 to 1 times (for infants, for example, 1 to 10 mm) the center-to-center spacing 31y in the front-to-rear direction LD of the row of protrusions 31 adjacent in the width direction WD.

[0103] <Explanation of Terms Used in the Specification> When the following terms are used in the specification, they have the following meanings unless otherwise specified in the specification.

[0104] The "front-to-back direction" refers to the direction indicated by the symbol LD in the figure (vertical direction), and the "width direction" refers to the direction indicated by the symbol WD in the figure (left-to-right direction), and the front-to-back direction and the width direction are perpendicular to each other.

[0105] - "Front side" means the side closest to the wearer's skin when worn, and "rear side" means the side farthest from the wearer's skin when worn.

[0106] "Front surface" means the surface of a component that is closest to the wearer's skin when worn, and "back surface" means the surface that is farthest from the wearer's skin when worn.

[0107] The "expanded state" means a state in which the material is stretched to the elastic limit in the expansion / contraction direction (in other words, contracted (including any contraction such as contraction due to an elastic member) or deployed flat without slack).

[0108] The term "elongation rate" refers to a value when the natural length is taken as 100%. For example, an elongation rate of 200% is equivalent to an elongation ratio of 2 times.

[0109] "Maximum elongation rate" means the elongation rate in the unfolded state.

[0110] "Artificial urine" is a mixture of 2 wt% urea, 0.8 wt% sodium chloride, 0.03 wt% calcium chloride dihydrate, 0.08 wt% magnesium sulfate heptahydrate, and 97.09 wt% ion-exchanged water, and is used at a temperature of 37°C unless otherwise specified.

[0111] "Gel strength" is measured as follows: 1.0 g of superabsorbent polymer is added to 49.0 g of artificial urine 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 using a curd meter (Curdmeter-MAX ME-500, manufactured by I.techno Engineering).

[0112] "Basis weight" is measured as follows. After pre-drying the sample or test piece, it is left in a test room or device under standard conditions (the test location is a temperature of 23±1°C and a relative humidity of 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), a sample measuring 100mm x 100mm is cut from the test piece once it has reached a constant weight. The weight of the sample is measured and multiplied by 100 to calculate the weight per square meter, which is the basis weight.

[0113] The "thickness" of thick members such as the absorber 56 and the absorbent element 50 is measured using a thickness measuring device (Peacock, Dial Thickness Gauge, Model G-30 (measurement range: 0 to 10 mm, measurement surface dimensions: circular terminal with a diameter of 60 mm, measurement force: approximately 1.7 N)) manufactured by Ozaki Manufacturing Co., Ltd., with the sample and the thickness measuring device held horizontally. The thickness of other thin materials, such as nonwoven fabrics, is measured using an automatic thickness measuring device (KES-G5 Handy Compression Measurement Program) with a load of 0.098 N / cm. ２ , and pressure area: 2 cm ２ The thickness is measured automatically under the following conditions. If it is impossible or inappropriate to measure the thickness, the apparent thickness may be used.

[0114] The "water absorption amount" is measured according to JIS K7223-1996 "Test method for water absorption amount of superabsorbent resins."

[0115] The "water absorption rate" is the "time to the end point" when 2 g of superabsorbent polymer and 50 g of physiological saline are used and the "test method for water absorption rate of superabsorbent polymer" according to JIS K7224-1996 is carried out.

[0116] Unless otherwise specified, the dimensions and positional relationships of each part refer to the dimensions and positional relationships in the deployed state, not in the natural length state.

[0117] If no environmental conditions for a test or measurement are specified, the test or measurement shall be carried out in a test room or device under standard conditions (temperature of 23±1°C, relative humidity of 50±2%).

[0118] The present invention is not limited to tape-type disposable diapers as described above, but can be applied to all disposable diapers, including pad-type and pants-type diapers, as long as they have rise-up gathers, and can also be applied to other absorbent articles such as sanitary napkins. In particular, disposable diapers for low birth weight infants prefer a soft, even if weak, fit rather than a firm one. Therefore, the rise-up gathers with the free portions described above are suitable for disposable diapers for low birth weight infants.

[0119] 11...liquid-impermeable sheet, 12...exterior nonwoven fabric, 12T...target portion, 13...connecting tape, 13A...connecting portion, 15...waist stretch portion, 16...raised portion, 30...top sheet, 31...convex portion, 50...absorbent element, 56...absorbent body, 56n...constricted portion, 58...packaging sheet, 60...standing gathers, 61...gathered stretch portion, 62...gathered sheet, 62f...outer layer, 62n...inner layer, 63...gathered elastic member, 64...side elastic member, 65...root portion, 66...main body portion, 67...front end portion, 68...middle portion, 69...rear end portion, 70...stretch sheet, 71...support sheet layer, 72...waist elastic member, BP...fixed portion, FP...free portion, LD...front-to-back direction, M...crotch portion, WD...width direction.

Claims

1. An absorbent body, a liquid-permeable top sheet arranged on the outer side of the absorbent body, and rising gathers provided on both sides of the surface of the top sheet in the width direction, wherein the rising gathers have a root portion attached to the outside in the width direction of an imaginary line continuing in the front-to-back direction along blocking positions on both sides of the surface of the top sheet in the width direction, and a main body portion extending inward in the width direction from the inner edge of the root portion in the width direction without being folded back, wherein the main body portion has front and rear end portions having fixing portions fixed to the top sheet, and a middle portion located between the front and rear end portions and not fixed to the top sheet, wherein at least the tip of the middle portion is provided with a gathered stretchable portion having an elongated gathered elastic member extending along the front-to-back direction, and wherein the gathered stretchable portion is a portion that elastically stretches between a natural length state in which it is contracted in the front-to-back direction together with the gathered elastic member, and an expanded state in which it is stretched in the front-to-back direction together with the gathered elastic member to a maximum elongation rate, an absorbent article characterized in that at least one of the front end and the rear end has a free portion that is not fixed to the top sheet over the entire front-to-back direction at the inner end in the width direction, and has the fixed portion adjacent to the outer side of the free portion in the width direction; the absorbent article has a waist stretchable portion adjacent to the back side of at least the free portion and the fixed portion on the outer side of the free portion in the width direction; the waist stretchable portion has a waist elastic member and is a portion that elastically stretches and contracts between a natural length state in which it contracts in the width direction together with the waist elastic member and has ridges extending in the front-to-back direction formed repeatedly in the width direction on the surface, and an expanded state in which it stretches in the width direction together with the waist elastic member to a maximum elongation rate and no longer has the ridges; the free portion is not fixed to the waist stretchable portion, and the fixed portion is fixed to the waist stretchable portion, and the boundary between the free portion and the fixed portion is located on the outer side of the ridges in the width direction.

2. An absorbent article as set forth in claim 1, wherein the width of said free portion is 5 mm or more, said gathered stretchable portion has a plurality of said gathered elastic members spaced apart in the width direction in a tip end region of said main body portion having a width equal to the width of said free portion, and said gathered elastic members are not provided outside said tip end region, said gathered stretchable portion extends across said intermediate portion and said free portion, and the front-to-back dimension of the portion of said gathered stretchable portion located within said free portion is 5 to 25% of the front-to-back dimension of said free portion.

3. An absorbent article according to claim 1 or 2, wherein the absorbent body spans the fixed portion of one of the rising gathers and the fixed portion of the other of the rising gathers, and the waist side edge of the absorbent body is located closer to the waist than the waist side end of the elastic gathered portion.

4. The absorbent article according to claim 1 or 2, wherein the front-to-back dimension of the portion of said free section that overlaps with said waist stretch section is 50% or more of the front-to-back dimension of said free section.

5. An absorbent article as claimed in claim 1 or 2, wherein the top sheet has a plurality of convex portions provided at intervals on the surface of an area that overlaps with the free portion in the unfolded state, and the thickness of the convex portions in the area of ​​the top sheet that overlaps with the free portion is greater than the thickness of the area that overlaps with the fixed portion.

6. The absorbent article according to claim 5, wherein the area of ​​the top sheet that overlaps with the fixing part does not have the protrusions and has a constant thickness.

7. An absorbent body, a liquid-permeable top sheet arranged on the outer side of the absorbent body, and rising gathers provided on both sides of the surface of the top sheet in the width direction, wherein the rising gathers have a root portion attached to the outside in the width direction of an imaginary line continuing in the front-to-rear direction along blocking positions on both sides of the surface of the top sheet in the width direction, and a main body portion extending inward in the width direction from the inner edge of the root portion in the width direction without being folded back, wherein the main body portion has front and rear end portions having fixing portions fixed to the top sheet, and a middle portion located between the front and rear end portions and not fixed to the top sheet, wherein an elongated gathered elastic member extending in the front-to-rear direction is attached to at least the tip of the middle portion, and wherein the middle portion contracts together with the gathered elastic member due to the contractile force of the gathered elastic member and is also stretchable together with the gathered elastic member, an absorbent article characterized in that at least one of the front end portion and the rear end portion has a free portion that is not fixed to the top sheet over the entire front-to-rear direction at the inner end in the width direction, and has the fixed portion on the outside in the width direction of the free portion; the top sheet has a plurality of convex portions provided at intervals on the surface of an area that overlaps with the free portion in an unfolded state; and the thickness of the convex portions in the area of ​​the top sheet that overlaps with the free portion is thinner than the thickness of the area that overlaps with the fixed portion.

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