Underpants type disposable wearing article

Abstract

To prevent deformation by an elastic member in an end part on a waist opening side of an absorber.SOLUTION: An absorber 56 includes an edge region 56E including an edge of a side of a waist opening WO and the entire part adjacent to a side of a crotch part M in a width direction WD. The entire part of the edge region 56E is positioned in a fixing region 201 of an interior body 200 and is fixed to an exterior body 12F, 12B. A groove 53 which is dented from a surface of the absorber 56 to the inside of the absorber 56 and has a bottom part 51 compressed in a thickness direction is provided across the entire part of the edge region 56 E in the width direction WD in a pattern continuing in the width direction WD. In the edge region 56E, a thickness of the bottom part 51 of the groove 53 is constant, and an area rate of the bottom part 51 of the groove 53 increases toward both side edges of the absorber 56 from a center in the width direction WD of the absorber 56.SELECTED DRAWING: Figure 10

Description

[Technical field]

[0001] The present invention relates to a pants-type disposable wearing article having an inner body that is excellent in shape retention. [Background technology]

[0002] Pant-type disposable wearing articles such as pants-type disposable diapers and pants-type sanitary napkins generally comprise an outer body having a front waist portion, a rear waist portion, and side seals formed by joining both side portions of these portions, and an inner body attached to the outer body so as to extend from the front waist portion to the rear waist portion, and the side seals are formed by joining both side portions of the front waist portion to both side portions of the rear waist portion, forming a waist opening and a pair of left and right leg openings (see, for example, Patent Document 1).

[0003] The waist portion of the outer cover is provided with an elastic member, so that the waist portion stretches in the width direction in a natural length state and has a stretchable region that is extensible in the width direction, allowing the waist portion to fit well against the body surface of the wearer.

[0004] The inner body has an absorbent body that continues from the front waist area through the crotch area to the rear waist area, and liquid in the excretory area is absorbed and retained by the absorbent body.

[0005] The front and rear waistbands have fixing regions for fixing the inner body to the outer body, and the absorbent body is generally fixed to the outer body in substantially the entire area that overlaps with the outer body. Therefore, when the stretchable regions of the front and rear waistbands overlap with the absorbent body, not only is the stretchability of the stretchable regions limited by the rigidity of the absorbent body, but the absorbent body is subjected to a contraction force in the width direction, which may make it more susceptible to twisting or cracking, reduce its absorption performance, or worsen the fit and appearance.

[0006] For this reason, in the past, it has become common to attach elongated elastic members continuously along the width direction over the entire front-to-rear direction of the outer cover in both the first region consisting of the parts of the front and rear waistbands that overlap with the absorbent body and between them and the side seals, and the second region between the first region and the waist opening, and to form a non-stretchable region in which the widthwise contraction force does not act on the part that overlaps with the absorbent body (where the contraction force is neutralized) by cutting almost the entire elastic member in the first region where it overlaps with the absorbent body into small pieces, and to make the rest into a stretchable region. As a result, in the first region, the region having the absorbent body is a non-stretchable region, and the side seal side of that (the part closer to the side seal) is an intermittent stretchable band of stretchable region, and the entire second region from one side seal to the other is a continuous stretchable band of stretchable region.

[0007] However, such pants-type disposable wearing articles have the problem that, when in a natural length state, as shown in FIG. 7, both corners on the waist opening side of the absorbent body selectively shrink in the width direction, while a middle portion in the width direction of the end portion on the waist opening side of the absorbent body hardly shrinks at all, and the middle portion in the width direction of the end portion on the waist opening side of the absorbent body bulges outward toward the back side (outer surface side), which hinders the product from being made compact (reduced in thickness) when packaged or carried, and makes the product appear to the user as being of low quality. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] JP 2019-150655 A Summary of the Invention [Problem to be solved by the invention]

[0009] SUMMARY OF THE PRESENT DISCLOSURE ... It is therefore a primary object of the present invention to provide a pants-type disposable wearing article in which deformation caused by an elastic member at the end portion of the absorbent body on the waist opening side is suppressed. [Means for solving the problem]

[0010] The pants-type disposable wearing article that solves the above problems is as follows. <First aspect> an exterior body having a front waist portion, a rear waist portion, and side seals formed by joining both side portions of the front waist portion and the rear waist portion; An inner body extending from a front waist portion through a crotch portion to a rear waist portion; a waist opening formed by a front edge of the front waist portion and a rear edge of the rear waist portion; and leg openings provided on both sides of the interior body, The exterior body has a fixing region where the interior body is fixed to at least the front waist circumference portion and the rear waist circumference portion, the inner body has an absorbent body continuing from a position overlapping with the front waistband portion to a position overlapping with the rear waistband portion, the absorbent body has an edge region including an edge on the waist opening side and an entire widthwise portion adjacent to the crotch side thereof, and the entire edge region is located in a fixing region of the inner body and is fixed to the outer body, a first region of the front waistband and the rear waistband, which consists of a portion overlapping the absorbent body and a portion between the absorbent body and the side seal, is an intermittent elastic band having a non-elastic region provided at least in the middle of the portion overlapping the absorbent body in the width direction and an elastic region provided between the non-elastic region and each of the side seals, and a second region located between the intermittent elastic band and the waist opening is a continuous elastic band whose elastic region continues in the width direction from one of the side seals to the other of the side seals; The elastic region of the intermittent elastic band and the continuous elastic band incorporate an elastic member, and is elastic between a natural length state in which the elastic member contracts in the width direction and an extended state in which the elastic member extends in the width direction. A pants-type disposable wearable article; A groove having a bottom portion that is recessed from the surface of the absorbent body into the absorbent body and compressed in the thickness direction is provided in a continuous pattern in the width direction over the entire width direction of the edge region, In the edge regions, from the center of the absorbent body in the width direction toward both side edges of the absorbent body, the thickness of the bottom of the groove is constant and the area ratio of the bottom of the groove increases, the area ratio of the bottom of the groove is constant and the thickness of the bottom of the groove decreases, or the area ratio of the bottom of the groove increases and the thickness of the bottom of the groove decreases. A pants-type disposable wearing article.

[0011] (Action and effect) By providing grooves in a predetermined pattern that extend from the surface of the absorbent body into the absorbent body and have bottoms that are compressed in the thickness direction, the compressed bottoms have a high density and high rigidity, improving the shape retention of the edge region and suppressing deformation caused by the elastic member at the end of the absorbent body on the waist opening side. However, if the shape retention is improved by making the area ratio and bottom thickness of the grooves uniform throughout the edge region, there is a risk that the flexibility of the edge region of the absorbent body will decrease. In contrast, by changing at least one of the area ratio of the bottom of the groove and the thickness of the bottom as in the present embodiment, and increasing the rigidity of the edge region stepwise or continuously from the center of the width of the absorbent body toward both side edges of the absorbent body, the shape retention of the edge region of the absorbent body increases as it approaches both corners, thereby suppressing a decrease in flexibility of the edge region of the absorbent body while suppressing deformation due to the elastic member at the end on the waist opening side of the absorbent body, which is preferable.

[0012] <Second aspect> the edge region is a region in which the grooves are continuous in a lattice pattern, a thickness and a width of a bottom of the groove in the edge region are constant, and an area of ​​a unit frame formed of the groove in the edge region is gradually reduced from a center in a width direction toward both side edges. A pants-type disposable wearing article according to a first embodiment.

[0013] (Action and effect) When the absorbent body is provided with a continuous grid pattern of grooves having bottoms that are recessed from the surface of the absorbent body into the absorbent body and compressed in the thickness direction, the bottoms of the grooves, which are dense and highly rigid, are continuous in a grid pattern, and the shape retention of the region having the grooves is particularly high. Here, although the shape retention changes depending on the thickness of the bottoms of the grooves of the absorbent body, the change is not large, and the influence on the absorption performance such as liquid diffusion is large, and the ease of manufacture is also reduced. In addition, if the width of the bottoms of the grooves is increased, the feeling of the hard bottoms of the grooves is easily transmitted to the skin. Therefore, as in this embodiment, it is preferable to make the area of ​​the unit frame consisting of the grooves gradually smaller from the center in the width direction toward both side edges while keeping the thickness and width of the bottoms of the grooves constant. As a result, the shape retention of the edge regions of the absorbent body becomes higher as it approaches both corners, so that it is possible to suppress the deformation caused by the elastic member at the end of the waist opening side of the absorbent body while suppressing the decrease in the flexibility of the edge regions of the absorbent body.

[0014] <Third aspect> The elastic members in the continuous stretchable band are elongated elastic members that are attached at intervals in the front-rear direction and extend along the width direction, The distance between the elongated elastic member closest to the edge region of the absorbent body and the edge region in the front-rear direction is within 15 mm. A pants-type disposable wearing article according to the first or second aspect.

[0015] (Action and effect) In pants-type disposable wearing articles, elongated elastic members are often used as a means for adding elasticity to the waist area of ​​the outer body. In this case, according to the knowledge of the present inventors, when the distance in the front-rear direction between the elastic member closest to the edge area of ​​the absorbent body and the edge area is within 15 mm, the end of the absorbent body on the waist opening side is particularly prone to deformation. Therefore, in such a case, it is particularly significant to increase the rigidity of the edge area stepwise or continuously from the center of the absorbent body in the width direction toward both side edges of the absorbent body.

[0016] <Fourth aspect> A specimen obtained by cutting out a portion of the continuous stretchable band from the edge region of the absorbent body to the waist opening side by 15 mm from one side seal to the other side seal is stretched to 90% of the total width in the expanded state, and then contracted to 50% of the total width in the expanded state, and the contraction force is 0.4 N or more. A pants-type disposable wearing article according to a third embodiment.

[0017] (Action and effect) According to the findings of the present inventors, in the case of this embodiment, the end portion of the absorbent body on the waist opening side is particularly susceptible to deformation, and therefore, in such a case, it is particularly significant to increase the rigidity of the edge region stepwise or continuously from the center of the absorbent body in the width direction toward both side edges of the absorbent body.

[0018] <Fifth aspect> The absorbent body is made of one or more layers made by mixing and accumulating pulp fibers and highly absorbent polymer particles, The basis weight of the pulp fibers in the absorbent body is 80 to 450 g / m 2 and The weight ratio of pulp fibers to superabsorbent polymer particles in the absorbent body is 20:80 to 80:20; The maximum thickness of the absorbent body is 1 to 20 mm, The thickness of the bottom portion is 5 to 40% of the maximum thickness of the absorbent body. The width of the bottom is 1 to 3 mm. The pants-type disposable wearing article according to any one of the first to fourth aspects.

[0019] (Action and effect) The dimensions of the grooves can be determined as appropriate, but in an absorbent body such as that of this embodiment, it is preferable to form the grooves within the range of this embodiment.

[0020] <Sixth aspect> The grooves are formed in a diagonal lattice pattern having a first portion inclined at 40 to 60 degrees clockwise in a plan view with respect to the front-rear direction and a second portion inclined at 40 to 60 degrees counterclockwise in a plan view with respect to the front-rear direction. 6. A pants-type disposable wearing article according to any one of claims 1 to 5.

[0021] (Action and effect) The groove pattern can be determined as appropriate, but a diagonal lattice pattern as in this embodiment is preferable. Effect of the Invention

[0022] As described above, the present invention provides advantages such as being able to suppress deformation caused by the elastic member at the end portion on the waist opening side of the absorbent body. [Brief description of the drawings]

[0023] [Figure 1] FIG. 2 is a plan view showing the front surface of the pants-type disposable diaper in an unfolded state. [Diagram 2] FIG. 2 is a plan view showing the underside of the pants-type disposable diaper in an unfolded state. [Diagram 3] 3 is a cross-sectional view of FIG. 1 along line 3-3. [Figure 4] This is a cross-sectional view of FIG. 1 along line 4-4. [Diagram 5] 5 is a cross-sectional view of FIG. 1 along line 5-5. [Figure 6] FIG. 2 is a plan view showing the surface of the inner body. [Figure 7] FIG. 2 is a front perspective view of the pants-type disposable diaper, viewed diagonally from below. [Figure 8] FIG. 4 is a cross-sectional view of a main part showing a mounted state. [Figure 9] FIG. [Figure 10] FIG. [Figure 11] 11 is an enlarged plan view showing a main part of FIG. 10. FIG. [Figure 12] FIG. [Figure 13] FIG. [Figure 14] (a) is a photograph of a pants-type disposable diaper sample A, and (b) is a photograph of a pants-type disposable diaper sample B. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] The above-mentioned pants-type disposable wearing article will be described in detail below with reference to an example of a pants-type disposable diaper shown in the attached drawings. Note that 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 (regular or irregular) spray application, or pattern coating (transfer of hot melt adhesive by letterpress printing). 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 the fixing or joining means for joining each component, material welding means such as heat sealing and 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.

[0025] 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 from synthetic fibers such as polyolefins such as polyethylene or polypropylene, polyesters, and polyamides (including single-component fibers and composite fibers such as core-sheath fibers), regenerated fibers such as rayon and cupra, and natural fibers such as cotton, 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), or hydrophobic or water-repellent fibers (including fibers that have been made water-repellent by a water-repellent agent). Furthermore, nonwoven fabrics are generally classified according to the length of the fibers, the sheet formation method, the fiber bonding method, and the laminated structure 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 (including SMS nonwoven fabrics and SMMS nonwoven fabrics in which a meltblown layer is sandwiched between spunbond layers), and the like, and any of these nonwoven fabrics can be used.

[0026] 1 to 7 show an example of a pants-type disposable diaper. The pants-type disposable diaper 100 includes a rectangular front exterior body 12F constituting a front waist-surrounding portion FT, a rectangular rear exterior body 12B constituting a rear waist-surrounding portion BT, and an inner body 200 joined to the middle of the exterior bodies 12F, 12B in the width direction WD so as to extend from the front exterior body 12F through the crotch portion M 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, whereby an opening formed by the front and rear edges 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 WD that are surrounded by the lower edges of the exterior bodies 12F, 12B and the side edges of the inner body 200 become leg openings LO through which the legs pass. The inner body 200 is a portion that absorbs and retains excrement such as urine, and the outer bodies 12F, 12B are portions that support the inner body 200 against the wearer's body. Furthermore, 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 of the waist opening WO of the front body F to the edge 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.

[0027] The pants-type disposable diaper 100 has a waist region T defined as the front-to-rear range having the side seals 12A (the front-to-rear range from the waist opening WO to the upper ends of the leg openings LO), and an intermediate region L defined as the front-to-rear range of the portion forming the leg openings LO (between the front-to-rear region having the side seals 12A of the front body F and the front-to-rear region having the side seals 12A of the rear body B). The portions of the front exterior body 12F and the rear exterior body 12B located in the waist region T, i.e., the front waist region FT and the rear waist region BT, can be conceptually divided into a "waist portion" W that forms the edge of the waist opening and a "lower waist portion" U that is the portion below this. Usually, when the front waist portion FT and the rear waist portion BT have a boundary where the stretch stress in the width direction WD changes (for example, the thickness or elongation rate of the elastic member changes), the waist portion W is located closer to the waist opening WO than the boundary closest to the waist opening WO, and when there is no such boundary, the waist portion W is located at the portion extending from the absorber 56 or the inner body 200 toward the waist opening WO. The length of these in the front-rear direction varies depending on the size of the product and can be appropriately determined. For example, the waist portion W can be 15 to 40 mm, and the waist lower portion U can be 65 to 120 mm. On the other hand, both side edges of the middle region L are narrowed in a U-shape or curved shape so as to fit around the legs of the wearer, and these are the areas where the wearer's legs are inserted. As a result, the pants-type disposable diaper in the opened state has a substantially hourglass shape as a whole.

[0028] (Fixed area of ​​the interior body) The inner body 200 can be fixed to the outer bodies 12F, 12B by a joining means such as heat sealing or ultrasonic sealing that uses material welding, or by a hot melt adhesive HM3. In the illustrated example, the back surface of the inner body 200 is fixed to the inner surface of the outer bodies 12F, 12B via the hot melt adhesive HM3. In the illustrated example, the fixing region 201 of the inner body 200 is provided in the region where the front waist portion FT and the rear waist portion BT overlap with the inner body 200. It is preferable that the fixing region of the inner body is provided over substantially the entire area except for the periphery of the region where the outer bodies 12F, 12B and the inner body 200 overlap.

[0029] (Exterior body) As shown in the figure, the exterior bodies 12F and 12B are composed of a rectangular front exterior body 12F that is a part that constitutes at least the front waistline portion FT (the waistline portion of the front body F) and a rectangular rear exterior body 12B that is a part that constitutes at least the rear waistline portion BT (the waistline portion of the rear body B). The front exterior body 12F and the rear exterior body 12B may not be continuous on the crotch side and may be separated in the front-to-back direction LD (two-piece exterior type), or may be continuous from the front body F through the crotch portion M to the rear body B (integrated exterior type), although not shown. The separation distance 12d in the front-to-back direction in the two-piece exterior type can be, for example, about 40 to 60% of the total length Y. In the example shown in the figure, the lower edges of the front exterior body 12F and the rear exterior body 12B are linear along the width direction WD, but at least one of the lower edges of the front exterior body 12F and the rear exterior body 12B may be curved so as to follow the leg circumference.

[0030] In a pants-type disposable diaper with a two-part exterior, the inner body 200 is exposed between the front exterior body 12F and the rear exterior body 12B, so that the liquid-impermeable sheet 11 is not exposed on the back surface of the inner body 200, it is preferable to provide a cover nonwoven fabric layer 13 on the back surface of the inner body 200, which extends from between the front exterior body 12F and the inner body 200 to between the rear exterior body 12B and the inner body 200. The inner surface and the outer surface of the cover nonwoven fabric layer 13 can be bonded to the opposing surfaces via a second hot melt adhesive HM2 and a third hot melt adhesive HM3, respectively. The nonwoven fabric used for the cover nonwoven fabric layer 13 can be appropriately selected from the same material as the exterior bodies 12F and 12B, for example.

[0031] In the example shown in Figures 1 and 2, the front-to-rear dimension of the rear outer body 12B is longer than that of the front outer body 12F, the front outer body 12F does not have a portion corresponding to the middle region L, and the rear outer body 12B has a buttocks covering portion 14 extending from the waist region T toward the middle region L, but the front-to-rear dimension LD of the front outer body 12F and the rear outer body 12B may be equal, and the front outer body 12F and the rear outer body 12B may not have a portion corresponding to the middle region L.

[0032] 3 to 5, the exterior bodies 12F, 12B are formed by bonding an outer sheet layer 12S and an inner sheet layer 12H adjacent to the outer and inner sides of the elastic members 15 to 17 described below by a bonding means such as a hot melt adhesive, welding, etc. The outer sheet layer 12S and the inner sheet layer 12H are formed by folding a single sheet material so that a crease is located on the waist opening side as shown in Fig. 5, or they can be formed by bonding two sheets of sheet material together (not shown).

[0033] The sheet material used for the outer sheet layer 12S and the inner sheet layer 12H is not particularly limited, but nonwoven fabric is preferable. When nonwoven fabric is used, the basis weight per sheet is 8 to 20 g / m 2 It is preferable to set the temperature to about 100°C.

[0034] In order to improve the fit around the waist of the wearer, the exterior bodies 12F and 12B have elastic members 15-17 attached between the outer sheet layer 12S and the inner sheet layer 12H at a predetermined stretch rate, and a stretchable region that stretches elastically in the width direction WD together with the elastic members 15-17 is formed. The stretchable region can stretch between a natural length state in which the elastic members 15-17 are contracted and wrinkled or pleated, and an elongated state in which the elastic members 15-17 are elongated in the width direction to a predetermined stretch rate without wrinkles. As the elastic members 15-17, in addition to elongated elastic members such as thread rubber (illustrated example), known elastic members such as band-shaped, net-shaped, film-shaped, etc. can be used without any particular limitation. As the elastic members 15-17, synthetic rubber or natural rubber may be used. In the exterior bodies 12F, 12B, the outer sheet layer 12S and the inner sheet layer 12H are bonded together, and the elongated elastic members 15-17 sandwiched therebetween can be fixed by at least one of various application methods of hot melt adhesives and material welding such as heat sealing and ultrasonic sealing. Since the flexibility is lost if the entire surface of the exterior bodies 12F, 12B is strongly fixed, it is preferable that the parts other than the bonding parts of the elongated elastic members 15-17 are not bonded or are weakly bonded. In the illustrated example, the hot melt adhesive is applied only to the outer peripheral surfaces of the elongated elastic members 15-17 by an application means such as a comb gun or a surwrap nozzle, and the elongated elastic members 15-17 are sandwiched between the two sheet layers 12S, 12H, so that the elongated elastic members 15-17 are fixed to the two sheet layers 12S, 12H and fixed between the two sheet layers 12S, 12H only by the hot melt adhesive applied to the outer peripheral surfaces of the elongated elastic members 15-17.

[0035] To explain the elastic members 15-17 in the illustrated example in more detail, a plurality of waist elastic members 17 are attached between the outer sheet layer 12S and the inner sheet layer 12H in the waist portion W of the outer bodies 12F, 12B at intervals in the front-rear direction and in a state stretched in the width direction at a predetermined stretch rate, forming a continuous waist stretch region over the entire width direction WD. Of the waist elastic members 17, one or more arranged in the region adjacent to the waist lower portion U may overlap the inner body 200, or may be provided on both sides of the width direction WD except for the width direction central portion overlapping the inner body 200. The waist elastic member 17 has a thickness of 300 to 940 dtex, particularly about 470 to 780 dtex (in the case of synthetic rubber; in the case of natural rubber, a cross-sectional area of ​​0.05 to 1.5 mm 2 , especially 0.1 to 1.0 mm 2 It is preferable to provide about 2 to 15, and especially about 4 to 10, rubber threads of about 12 mm each, and especially at intervals of 3 to 7 mm, so that the elasticity of the waist portion W in the width direction WD is about 150 to 300%, and especially about 200 to 280%. It is not necessary for the waist portion W to use elastic members of the same thickness or to have the same elasticity in the front-to-rear direction LD, and for example the thickness or elasticity may be different in some parts.

[0036] In addition, between the outer sheet layer 12S and the inner sheet layer 12H in the waist lower portion U of the exterior bodies 12F, 12B, a plurality of waist lower elastic members 15 made of elongated elastic members are attached at intervals in the front-rear direction and in a state stretched in the width direction at a predetermined stretch rate, forming waist lower stretchable regions on both sides in the width direction WD except for the widthwise center portion overlapping with the interior body 200. The waist lower elastic members 15 are generally made of a material having a thickness of 300 to 940 dtex, particularly about 470 to 780 dtex (in the case of synthetic rubber; in the case of natural rubber, a cross-sectional area of ​​0.05 to 1.5 mm 2 , especially 0.1 to 1.0 mm 2It is preferable to provide about 5 to 30 rubber threads of about 120 mm each at intervals of 1 to 15 mm, especially 3 to 8 mm, so that the elasticity in the width direction WD of the waist lower portion U is about 200 to 350%, especially 240 to 300%. It is not necessary for the waist lower portion U to use elastic members of the same thickness or to have the same elasticity in the front-to-back direction LD, and the thickness or elasticity may be partially different.

[0037] Between the outer sheet layer 12S and the inner sheet layer 12H in the buttocks cover portion 14 of the rear exterior body 12B, one or more buttocks cover elastic members 16 made of elongated elastic members are attached at intervals in the vertical direction and in a state stretched along the width direction at a predetermined stretch rate on both sides in the width direction WD except for the width direction central portion overlapping with the inner body 200, forming buttocks cover stretchable regions on both sides in the width direction WD except for the width direction central portion overlapping with the inner body 200. The buttocks cover elastic member 16 has a thickness of 300 to 940 dtex, particularly about 470 to 780 dtex (in the case of synthetic rubber; in the case of natural rubber, a cross-sectional area of ​​0.05 to 1.5 mm 2 , especially 0.1 to 1.0 mm 2 It is preferable to fix about 2 to 10 rubber threads (approximately 150 to 300% elongation, particularly 180 to 260%) at intervals of 5 to 40 mm, particularly 5 to 20 mm.

[0038] Of the front waistband FT and the rear waistband BT, the first region consisting of the portion overlapping with the absorbent 56 and the portion between this and the side seal 12A is an intermittent stretch band A1 having a non-stretchable region 12X provided in at least the middle portion in the width direction WD of the portion overlapping with the absorbent 56, and a stretchable region provided between each of the non-stretchable region 12X and the side seal 12A, and it is preferable that the second region located between this intermittent stretch band A1 and the waist opening WO is a continuous stretch band A2 whose stretchable region continues in the width direction WD from one side seal 12A to the other side seal 12A.

[0039] The intermittent stretch band A1 in the illustrated example may extend beyond the range of the first region (beyond the absorbent 56) to the waist opening WO side as long as it includes the first region. In the illustrated example, only the first region in the rear waistband BT is the intermittent stretch band A1, and the area between the first region and the waist opening WO is the continuous stretch band A2, and in the front waistband FT, the area consisting of the part overlapping the fixed region 201 of the inner body 200 and the part between this and the side seal 12A (the area continuing from the first region to the waist opening WO side) is the intermittent stretch band A1, but is not limited to this. Therefore, these may be reversed, or the area consisting of the part overlapping the fixed region 201 of the inner body 200 and the part between this and the side seal 12A in both the front waistband FT and the rear waistband BT may be the intermittent stretch band A1, or only the first region may be the intermittent stretch band A1 in both the front waistband FT and the rear waistband BT. In addition, the intermittent stretch band A1 in the illustrated example is formed in a range in the front-to-back direction LD that includes only the lower waist stretch area having the lower waist elastic member 15, but the range may be expanded toward the waist opening WO to include a portion of the waist stretch area having the lower waist elastic member 17.

[0040] In the illustrated example, the continuous stretchable band A2 is formed only by a waist stretchable region having a waist elastic member 17 in the front waist portion FT, and is formed by the entire waist stretchable region having the waist elastic member 17 and a part of the lower waist stretchable region including the lower waist elastic member 15 in the rear waist portion BT, but is not limited to this. Therefore, these may be reversed, and the continuous stretchable band A2 in both the front waist portion FT and the rear waist portion BT may be formed only by a waist stretchable region having a waist elastic member 17, or may be formed by the entire waist stretchable region having the waist elastic member 17 and a part of the lower waist stretchable region having the lower waist elastic member 15.

[0041] As shown in the figure, if the first region consisting of the part overlapping with the absorbent body 56 and the part between it and the side seal 12A is an intermittent stretch band A1 instead of a continuous stretch band A2, the absorbent body 56 will not shrink more than necessary in the width direction WD, and there will be no deterioration in fit, no poor appearance due to bulkiness, and no deterioration in absorbency. In addition to the case where the elastic members 15, 16 are present only on both sides in the width direction WD in such an intermittent stretch band A1, there is also a case where the elastic members 15, 16 are present across the absorbent body 56 from one side to the other in the width direction WD, but the widthwise intermediate part or the entire part overlapping with the absorbent body 56 is a non-stretch region 12X where almost no contraction force acts (effectively equivalent to no elastic members 15, 16 being provided) due to the elastic members 15, 16 being cut into small pieces, and both sides in the width direction WD are stretch regions (parts where contraction force acts). The non-stretchable region 12X is preferably located between both side edges of the inner body 200, and more preferably between both side edges of the absorbent body 56. The dimension in the width direction WD of the non-stretchable region 12X can be determined as appropriate, but is preferably 0.6 to 1.2 times, and more preferably 0.8 to 1.0 times, the maximum width of the absorbent body 56. The dimension in the width direction WD of the non-stretchable region 12X is preferably 0.5 to 1.0 times, and more preferably 0.6 to 0.8 times, the dimension in the width direction WD of the continuous stretchable band A2.

[0042] (Interior body) The shape of the inner body 200 is arbitrary, but in the illustrated example, it is rectangular. As shown in Figures 3 to 5, the inner body 200 comprises a liquid-permeable top sheet 30 that faces the wearer's skin, a liquid-impermeable sheet 11, and an absorbent element 50 interposed therebetween. Reference numeral 60 denotes a side flap 60 having flat gathers.

[0043] (Top sheet) The top sheet 30 can be made of any liquid-permeable material, such as a perforated or non-perforated nonwoven fabric, a perforated plastic sheet, or the like. However, when the top sheet 30 also serves as a covering material for the liquid-impermeable sheet layer 64, as in the example shown in Figures 3 and 4, it is preferable for the top sheet 30 to be a nonwoven fabric.

[0044] Both side portions of the top sheet 30 may be folded back to the back side of the absorbent element 50 at the side edges of the absorbent element 50, or may not be folded back and may extend beyond the side edges of the absorbent element 50. If necessary, the overall width of the top sheet 30 may be made shorter than the overall width of the absorbent element 50, and both side edges of the top sheet 30 may be located above the absorbent element 50.

[0045] (middle seat) Although not shown, an intermediate sheet (also called a "second sheet") that has a faster liquid permeability than the top sheet 30 can be provided in order to quickly transfer liquid that has permeated the top sheet 30 to the absorbent body. This intermediate sheet is intended to quickly transfer liquid to the absorbent body, improve the absorption performance of the absorbent body, and prevent the "backflow" phenomenon of absorbed liquid from the absorbent body. The intermediate sheet can also be omitted.

[0046] (Liquid-impermeable sheet) The material of the liquid-impermeable sheet 11 provided on the back side of the absorbent 56 is not particularly limited, but may be, for example, a plastic film made of a polyolefin resin such as polyethylene or polypropylene. In recent years, it is preferable to use a liquid-impermeable and moisture-permeable material that has been used with preference from the viewpoint of preventing stuffiness for the liquid-impermeable sheet 11. 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 to form a sheet and then stretching it in a uniaxial or biaxial direction is widely used.

[0047] The liquid-impermeable sheet 11 can be configured to extend into the side flaps to improve the waterproofness of the flat gathers, as in the example shown in Figures 3 and 4, or it can be made wide enough to fit on the back side of the absorbent element 50 (not shown), or it can be folded back to the front side at the side edge of the absorbent element 50 and extend between the absorbent element 50 and the top sheet 30.

[0048] (Absorption element) 3, 4 and 9, 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.

[0049] (Absorbent) The absorbent body 56 can be formed by a fiber assembly. As the fiber assembly, in addition to stacking staple fibers such as cotton-like pulp or synthetic fibers, a filament assembly obtained by opening a tow (fiber bundle) of synthetic fibers such as cellulose acetate as required can be used. When stacking cotton-like pulp or staple fibers, the fiber weight is, for example, 80 to 450 g / m 2 Approximately 80 to 200 g / m 2 In the case of a filament aggregate, for example, the weight is 30 to 120 g / m 2 In the case of synthetic fibers, the fineness is, for example, 1 to 16 dtex, preferably 1 to 10 dtex, and more preferably 1 to 5 dtex.

[0050] It is preferable that superabsorbent polymer particles are mixed in the fiber aggregate. 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 ratio 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 ratio 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.

[0051] The material of the superabsorbent polymer particles is not particularly limited, but is preferably one with a water absorption capacity of 40 g / g or more (JIS K7223-1996 "Test method for water absorption capacity of superabsorbent resins"). The superabsorbent polymer particles include starch-based, cellulose-based and synthetic polymer-based ones, and starch-acrylic acid (salt) graft copolymers, saponified starch-acrylonitrile copolymers, crosslinked products of sodium carboxymethylcellulose and acrylic acid (salt) polymers can be used. The shape of the superabsorbent polymer particles is preferably a powdery or granular one as is commonly used, but other shapes can also be used.

[0052] The highly absorbent polymer particles preferably have a water absorption speed of 70 seconds or less, particularly 40 seconds or less. If the water absorption speed is too slow, the liquid supplied into the absorbent body 56 tends to flow back out of the absorbent body 56, which is called backflow.

[0053] Moreover, the highly absorbent polymer particles preferably have a gel strength of at least 1000 Pa. This makes it possible to effectively prevent the sticky feeling after absorbing liquid, even when the absorbent body 56 is bulky.

[0054] The basis weight of the highly absorbent polymer particles can be appropriately determined according to the absorption amount required for the application of the absorbent body 56. Therefore, although it cannot be generally stated, it is generally in the range of 50 to 350 g / m 2 The polymer weight is 50 g / m 2 If it is less than 350g / m, it will be difficult to ensure sufficient absorption. 2 Above this, the effect saturates.

[0055] The ratio of fibers and superabsorbent polymer particles in the absorbent body 56 is not particularly limited, and for example, the weight ratio of pulp fibers:superabsorbent polymer particles can be 20:80 to 80:20, more preferably 40:60 to 60:40. In particular, when the weight ratio of pulp fibers:superabsorbent polymer particles is 40:60 to 60:40, the absorbent body 56 can be thinner than that of the same area and the same absorption amount. The thickness 56t of the absorbent body 56 is not particularly limited, and can be 1 to 20 mm, more preferably 2 to 5 mm.

[0056] The absorbent body 56 continues from the front waistband portion FT to the rear waistband portion BT. The entire edge region 56E of the absorbent body 56, including at least the edge on the waist opening WO side and the entire width direction WD of the portion adjacent to the crotch portion M side, (preferably the entire absorbent body 56) is located in the fixing region 201 of the inner body 200, and is preferably fixed to the outer bodies 12F, 12B via the packaging sheet 58, the liquid-impermeable sheet 11, the hot melt adhesive HM3, etc. The symbol 56X indicates the maximum width (total width) of the absorbent body 56.

[0057] In order to ensure the amount of absorption in the crotch area M, it is preferable that the absorbent body 56 has a substantially rectangular shape, but as shown in Figs. 1, 2 and 10, it is preferable that the absorbent body 56 has a minimum width portion 56N in the crotch area M and has widened portions 56V that gradually widen from the minimum width portion 56N to the maximum width portion 56M in front of the crotch area M and to the maximum width portion 56M behind the crotch area M, because the narrowed portions 56N, 56V consisting of the minimum width portion 56N and the widened portions 56V improve the fit of the inner thighs. In the latter case, in order to ensure the amount of absorption in the crotch area M, it is preferable that the dimension in the width direction WD of the minimum width portion 56N is 0.8 times or more the maximum width 56X of the absorbent body 56. In addition, it is preferable that the dimension in the front-rear direction of the narrowed portions 56N, 56V is about 20 to 30% of the total length Y of the product.

[0058] In addition, the crotch region M means the range in the front-to-back direction LD including the constricted portions 56N, 56V when the absorbent body 56 has the above-mentioned constricted portions 56N, 56V; when the absorbent body 56 does not have the constricted portions 56N, 56V but the outer shape in the unfolded state has constricted portions as in the illustrated example, it means the range in the front-to-back direction LD including the constricted portion of this outer shape (in the illustrated example, between the front outer body 12F and the rear outer body 12B); and when there are no constricted portions, it means the portion located in the center in the front-to-back direction LD and whose dimension in the front-to-back direction LD is 20 to 30% of the total product length Y.

[0059] (packaging sheet) When the wrapping sheet 58 is used, the material may be a liquid-permeable material such as tissue paper, particularly crepe paper, nonwoven fabric, polylaminated nonwoven fabric, or a sheet with small holes. However, it is preferable that the sheet is one from which the highly absorbent polymer particles do not escape. When using nonwoven fabric instead of crepe paper, a hydrophilic nonwoven fabric having a dense layer is preferable. As such a nonwoven fabric, a laminated nonwoven fabric (SMS nonwoven fabric, SSMMS nonwoven fabric, etc.) in which one or more meltblown layers are laminated with one or more protective layers such as a non-spunbonded layer that protects the meltblown layer is particularly preferable, and the material may be polypropylene, a polyethylene / polypropylene composite, or the like. The basis weight is 5 to 40 g / m 2 , especially 8 to 20 g / m 2 It is preferable that the following be used.

[0060] The packaging structure of the packaging sheet 58 can be determined as appropriate, but from the standpoint of ease of manufacture and preventing leakage of superabsorbent polymer particles from the front and rear edges, it is preferable to wrap it around the front and rear surfaces and both side surfaces of the absorbent body 56 in a cylindrical shape, with the front and rear edges protruding from the front and rear of the absorbent body 56, and to crush these protruding portions in the front and rear directions and join them with a joining means such as a hot melt adhesive.

[0061] (Side flap) As shown in Figs. 1 to 4, 7 and 8, the inner body 200 preferably has side flaps 60. The side flaps 60 are a pair of portions extending from the side edges of the absorbent body 56 on both sides in the width direction WD, and each extends in the front-rear direction LD from an area overlapping with the waist-surrounding stretchable area of ​​the front body F (in the illustrated example, an area having the waist-lower elastic member 15) to an area overlapping with the waist-surrounding stretchable area of ​​the back body B (in the illustrated example, an area having the waist-lower elastic member 15). The side flaps 60 also have side nonwoven fabric 66 extending from the front surface of the side flap 60 through the side edges of the side flap 60 to the back surface of the side flap 60, and elongated gather elastic members 631 to 633 provided between the front surface portion 61 and the back surface portion 62 along the front-rear direction LD. The front surface portion 61 and the back surface portion 62 extend over the entire side flap 60 in the front-rear direction LD. In the illustrated example, the surface portion 61 is formed by the folded-back portion 66r of the side nonwoven fabric 66, but is not limited thereto. The front end and rear end of the side flap 60 are not contracted in the front-rear direction LD together with the gathered elastic members 631-633, and the surface portion 61 is fixed to the back portion 62 to form a side non-stretchable region 70 having a fixed portion 67. The portion between the front and rear side non-stretchable regions 70 of the side flap 60 is a flat gathered region 80 to which the gathered elastic members 631-633 are fixed, contracted in the front-rear direction LD together with the gathered elastic members 631-633, and extensible in the front-rear direction LD together with the gathered elastic members 631-633. This pants-type disposable diaper does not have three-dimensional gathers that rise up on the front side, and has only flat gathers of the side flap 60. In the illustrated example of the fixing portion 67, the front surface portion 61 is indirectly fixed to the back surface portion 62 via the liquid-impermeable sheet layer 64, but if no other components such as the liquid-impermeable sheet layer 64 are interposed, the front surface portion 61 will be directly fixed.

[0062] The dimension of the side non-stretchable region 70 in the front-rear direction LD may be different at the front end and the rear end of the side flap 60 as shown in the illustrated example, or may be the same. In addition, the reference symbol 60w in the figure indicates the dimension in the width direction WD of the side flap 60. Also, the reference symbol w1 indicates the distance in the width direction WD between the fixing part 67 and the side edge of the side non-stretchable region 70 (first distance), the reference symbol w2 indicates the dimension in the width direction WD of the part not fixed to the exterior body 12 on both sides (side flaps) of the interior body (second distance), the reference symbol w3 indicates the dimension in the width direction WD of the fixing part 67, the reference symbol w4 indicates the distance in the width direction WD between the fixing part 67 and the side edge of the absorbent body 56 (third distance), and the reference symbol w5 indicates the distance in the width direction WD between the fixing part 67 and the edge on the center side of the width direction WD of the surface part 61 (fourth distance).

[0063] The gathered elastic members 631-633 may be elongated elastic members such as rubber threads or rubber strips. When rubber threads are used, the thickness of the gathered elastic members 631-633 is preferably 400-950 dtex, more preferably 470-780 dtex. The elongation rate of the gathered elastic members 631-633 is preferably 200-320%, more preferably 240-320%. In the figure, reference numeral 631 indicates a first gathered elastic member located first from the absorbent body 56 side, reference numeral 632 indicates a second gathered elastic member located second, and reference numeral 633 indicates a third gathered elastic member located third or later. In addition, symbol d1 indicates the distance (first distance) in the width direction WD between the side edge of the widest portion 56M of the absorbent body 56 and the first gathered elastic member 631, symbol d2 indicates the distance (second distance) in the width direction WD between the first gathered elastic member 631 and the second gathered elastic member 632, and symbol d3 indicates the distance in the width direction WD between the second gathered elastic member 632 and the third gathered elastic member 633 and the distance (third distance) in the width direction WD between adjacent third gathered elastic members 633.

[0064] In the side flap 60, at least one of hot melt adhesives applied by various application methods and material welding fixing means such as heat sealing and ultrasonic sealing can be used to bond adjacent layers in the thickness direction and fix the gathered elastic members 631-633 sandwiched therebetween. If the entire surfaces of adjacent layers on the front and back sides of the gathered elastic members 631-633 are bonded together, flexibility is lost, so it is preferable that the parts other than the adhesive parts of the gathered elastic members 631-633 are not bonded or are weakly bonded. In the illustrated example, hot melt adhesive is applied only to the outer peripheral surfaces of the gathered elastic members 631-633 by an application means such as a comb gun or a surwrap nozzle, and the gathered elastic members 631-633 are sandwiched between adjacent layers on the front and back sides, so that the gathered elastic members 631-633 are fixed to adjacent layers on the front and back sides and the layers adjacent to the front and back sides of the gathered elastic members 631-633 are fixed to each other only by the hot melt adhesive applied to the outer peripheral surfaces of the gathered elastic members 631-633. When there is an end portion of a nonwoven fabric or sheet separated from the gathered elastic members 631-633, such as the end portion of the top sheet 30 in the illustrated example, a separate hot melt adhesive (first hot melt adhesive HM1 in the illustrated example) can be applied to secure this end portion.

[0065] The side nonwoven fabric 66 may be 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, and may be treated with a water repellent agent such as silicone as necessary. The fiber basis weight is 10 to 30 g / m. 2 3 and 4, as can be seen from the fact that the surface nonwoven fabric layer on the proximal side of the nonwoven fabric-free portion 65 is formed by the top sheet 30, it is also possible to make the materials of the surface nonwoven fabric layer and the back nonwoven fabric layer partially different, and it is also possible to make the materials of the surface nonwoven fabric layer and the back nonwoven fabric layer different.

[0066] (groove) As shown in Figs. 9 to 11, the absorbent body 56 is preferably provided with grooves 53 having bottoms 51 that are recessed from the surface of the absorbent body 56 into the absorbent body 56 and compressed in the thickness direction. The bottoms 51 of the grooves 53 are high-density parts that are compressed by pressing (direct pressure) and have a substantially uniform thickness. Hereinafter, parts other than the bottoms 51 are referred to as non-compressed parts 52. The non-compressed parts 52 are parts that are thicker and have a lower density than the bottoms 51, but even in the non-compressed parts 52, the absorbent body 56 is deformed as if pulled by the compression of the bottoms 51 near the periphery of the bottoms 51, and as a result, the density increases as it approaches the bottoms 51. As long as the non-compressed parts 52 are thicker and have a lower density than the bottoms 51, the entire non-compressed parts 52 may be compressed in the thickness direction simultaneously with, before, or after the compression process for forming the bottoms 51. The shape and arrangement of the non-compressed parts 52 are determined according to the shape and arrangement of the bottoms 51.

[0067] The grooves 53 in the absorbent body 56 may be formed by subjecting only the absorbent body 56 to embossing or the like with or without heating, but they may also be formed including the absorbent body 56 and other laminated components by embossing the absorbent body 56 in a laminated state, such as the absorbent element 50 (i.e., together with the packaging sheet 58) or the inner body 200.

[0068] If the above-mentioned grooves 53 are provided in a pattern that is continuous in the width direction WD over the entire width direction WD of the edge region 56E including the entire width direction WD of the waist opening WO side edge of the absorbent body 56 and the part adjacent to the crotch M side, the compressed bottom 51 has a high density and high rigidity, so that the shape retention of the edge region 56E is improved and deformation due to the elastic member at the end of the waist opening WO side of the absorbent body 56 can be suppressed. However, if the shape retention is improved by the uniform area ratio of the bottom 51 of the groove 53 and the thickness of the bottom 51 over the entire edge region 56E, the flexibility of the edge region 56E of the absorbent body 56 may decrease. Therefore, it is preferable that the thickness of the bottom 51 of the groove 53 is constant and the area ratio of the bottom 51 of the groove 53 increases from the center of the absorbent body 56 in the width direction WD to both side edges of the absorbent body 56. Alternatively, although not shown, the area ratio of the bottom 51 of the groove 53 may be constant and the thickness of the bottom 51 of the groove 53 may decrease, or the area ratio of the bottom 51 of the groove 53 may increase and the thickness of the bottom 51 of the groove 53 may decrease. By changing at least one of the area ratio of the bottom 51 of the groove 53 and the thickness of the bottom 51 in this manner to increase the rigidity of the edge region 56E stepwise or continuously from the center of the absorbent body 56 in the width direction WD toward both side edges of the absorbent body 56, the shape retention of the edge region 56E of the absorbent body 56 increases toward both corners, so that the deformation of the end of the absorbent body 56 on the waist opening WO side by the waist elastic member 17 and the waist lower elastic member 15 can be suppressed while suppressing the decrease in flexibility of the edge region 56E of the absorbent body 56.

[0069] The above-mentioned grooves 53 may be formed in the entire absorbent body 56, or may be formed only in the edge region 56E, or only in a part of the front-rear direction including the edge region 56E, as long as the grooves 53 are provided in a pattern that is continuous in the width direction WD throughout the entire edge region 56E of the absorbent body 56. In particular, as shown in the illustrated example, if the pattern of the grooves 53 in the edge region 56E continues uniformly throughout the entire front-rear direction LD of the absorbent body 56, positioning of the grooves 53 in the front-rear direction LD is not required, which is preferable because it makes manufacturing easier. However, the edge region 56E and the other regions may have grooves 53 with different patterns. Also, the grooves 53 may be formed in different patterns in the edge region 56E of the front body F and the edge region 56E of the back body B. Furthermore, in both the edge region 56E of the front body F and the edge region 56E of the back body B, at least one of the thickness of the bottom 51 of the groove 53 and the area ratio of the bottom 51 of the groove 53 may change from the center of the absorbent 56 in the width direction WD toward both side edges of the absorbent 56, as described above, but only one of the edge region 56E of the front body F and the edge region 56E of the back body B may have at least one of the thickness of the bottom 51 of the groove 53 and the area ratio of the bottom 51 of the groove 53 changed as described above, and the other may have grooves 53 in a uniform pattern in the width direction WD, or may not have grooves 53 at all.

[0070] The dimension of the edge region 56E in the front-rear direction LD can be appropriately determined as long as it is equal to or smaller than the dimension of the front waistband FT and the rear waistband BT in the front-rear direction LD, the groove 53 is provided in the edge region 56E and is continuous in the width direction WD, and the area ratio of the bottom 51 can be changed from the center of the absorbent body 56 in the width direction WD toward both side edges of the absorbent body 56. As an example, the dimension of the edge region 56E in the front-rear direction LD is preferably 40 mm or more, more preferably 60 mm or more. In addition, when the groove 53 is provided in a lattice shape as described later, it is preferable that the dimension of the edge region 56E in the front-rear direction LD is twice or more the dimension of the smallest unit frame in the front-rear direction LD, because one smallest unit frame can be always present in the edge region 56E, and it is more preferable that the dimension of the edge region 56E in the front-rear direction LD is twice or more the dimension of the largest unit frame in the front-rear direction LD, because the unit frame can always be present throughout the entire width direction WD in the edge region 56E. As in the illustrated example, when the pattern of grooves 53 in the edge region 56E continues uniformly throughout the entire front-to-back direction LD of the absorbent body 56, the dimension of the edge region 56E in the front-to-back direction LD is equal to the dimension of the front waist region FT and the rear waist region BT in the front-to-back direction LD, as shown in FIG. 10.

[0071] The dimensions and number of the bottoms 51 of the grooves 53 can be determined as appropriate, but it is preferable that the depth 51h of the bottoms 51 (thickness 56t of the absorbent body 56 - thickness 51t of the groove bottoms) is 0.5 to 5 mm, and the area ratio of the bottoms 51 of the grooves 53 (the ratio of the area of ​​the bottoms 51 to the surface of the absorbent element 50) is 20 to 40%.

[0072] As long as the grooves 53 having the bottoms 51 are continuous in the width direction WD, they may be provided in a continuous lattice pattern as shown in Figures 10 and 11, or, although not shown, a single groove 53 or a plurality of grooves 53 along the width direction WD may be provided at intervals in the front-rear direction LD, a single groove 53 or a plurality of grooves 53 along an oblique direction may be provided at intervals in a direction perpendicular to the continuous direction of the grooves 53, a single or a plurality of grooves 53 extending in a wavy line shape may be provided, or other geometric patterns may be provided, or a continuous pattern may be provided with a motif of characters, animals, plants, etc. In particular, when the grooves 53 are provided in a continuous lattice pattern, the pulp fibers and superabsorbent polymer particles constituting the absorbent body 56 are constrained within the unit frame 54 (minimum frame) consisting of the bottoms 51 compressed in the thickness direction, so that the absorbent body 56 can be prevented from twisting or cracking.

[0073] The width 51w of the bottom 51 of the groove 53 (the width of the bottom of the compressed portion formed in the absorbent element 50) can be determined appropriately, but in normal cases, it is preferably about 1 to 3 mm.

[0074] The thickness 51t of the bottom 51 of the groove 53 can be determined as appropriate, but in general, it is preferably 5 to 40% of the maximum value of the thickness 50t of the absorbent element 50, and particularly preferably 5 to 30%.

[0075] When the grooves 53 are provided in a lattice pattern, the shape of the unit frames 54 is not particularly limited, and may be a substantially square shape as in the illustrated example, a substantially rhombus (excluding a square), or another polygonal shape such as a substantially rectangular shape, a substantially square shape, a substantially triangular shape, etc. Furthermore, as long as the bottoms 51 of the grooves are provided in a lattice pattern, unit frames 54 of different shapes may be included.

[0076] One preferred lattice pattern of the grooves 53 is an oblique lattice pattern consisting of first portions 51a extending in a direction inclined by 40 to 60° (more preferably 45 to 50°) clockwise in plan view with respect to the front-rear direction LD, and second portions 51b extending in a direction inclined by 40 to 60° (more preferably 45 to 50°) counterclockwise in plan view with respect to the front-rear direction LD, as shown in the example of Fig. 10 and Fig. 11. In this case, the shape of the unit frame 54 is substantially rhombus. It is particularly preferred that the angle of the first portions 51a and the second portions 51b with respect to the front-rear direction LD is 45 degrees.

[0077] The dimensions of the unit frame 54 can be determined as appropriate, but if they are too large, the effect of improving rigidity will be poor, and if they are too small, the frame will be too hard. Therefore, in normal cases, it is preferable that the dimension 54x of the unit frame 54 in the width direction WD is about 15 to 20 mm. Also, it is preferable that the dimension 54y of the unit frame 54 in the front-rear direction LD is about 15 to 20 mm.

[0078] When changing the area ratio of the bottoms 51 of the grooves 53 in the width direction WD of the absorbent body 56, the width of the bottoms 51 of the grooves 53 can be changed while keeping the pattern of the grooves 53 approximately constant, or the pattern of the grooves 53 can be changed while keeping the width 51w of the bottoms 51 of the grooves 53 approximately constant, or both the pattern of the grooves 53 and the width 51w of the bottoms 51 of the grooves 53 can be changed. However, if the width 51w of the bottoms 51 of the grooves 53 is increased to increase the area ratio of the bottoms 51 of the grooves 53, the touch of the hard bottoms 51 of the grooves 53 is easily transmitted to the skin. Therefore, as shown in the illustrated example, it is preferable to change the pattern of the grooves 53 (specifically, the number of grooves 53 per unit area) while keeping the width 51w of the bottoms 51 of the grooves 53 approximately constant. Furthermore, when the thickness of the bottoms 51 of the grooves 53 is changed in the width direction WD of the absorbent body 56, the change in the shape retention of the absorbent body 56 is not large, but the effect on the absorption performance such as liquid diffusibility is large, and the ease of manufacture is also reduced. Therefore, although it is possible to change the thickness of the bottoms 51 of the grooves 53 while keeping the area ratio of the bottoms 51 of the grooves 53 approximately constant, it is more preferable to change the area ratio of the bottoms 51 of the grooves 53 while keeping the thickness of the bottoms 51 of the grooves 53 approximately constant.

[0079] 10 to 13 show some preferred examples of groove patterns. In these examples, the width 51w and thickness of the bottom 51 of the groove 53 are approximately constant, while the pattern of the groove 53 changes in the width direction WD so that the area ratio of the bottom 51 of the groove 53 increases stepwise from the center of the absorbent body 56 in the width direction WD toward both side edges of the absorbent body 56. The size of the area of ​​each unit frame 54 can be determined appropriately, but of a pair of unit frames adjacent in the width direction to each other so as to have a common side, the area of ​​the larger unit frame is preferably 1.1 to 2.5 times the area of ​​the smaller unit frame.

[0080] When the grooves 53 have a lattice pattern, as shown in Figures 10, 11, and 12, a plurality of shapes of the unit frames 54 are combined to form a pattern in which the area of ​​the unit frames 54 gradually decreases from the center in the width direction WD toward both side edges, thereby making it possible to gradually increase the area ratio of the bottoms 51 of the grooves 53 from the center in the width direction WD of the absorbent body 56 toward both side edges of the absorbent body 56. Also, as shown in Figure 13, by combining unit frames 54 of different sizes although the shape of the unit frames 54 is the same (diamond (square) in the illustrated example), it is possible to gradually increase the area ratio of the bottoms 51 of the grooves 53 from the center in the width direction WD of the absorbent body 56 toward both side edges of the absorbent body 56.

[0081] More specifically, the pattern of the grooves 53 in the edge region 56E in the example shown in Figures 10 and 11 is a diagonal lattice pattern. In this pattern, diamond-shaped first unit frames 54a having the largest area are lined up without gaps in the center of the width direction WD, rectangular second unit frames 54b having one side common to the first unit frames 54a and a short side intersecting the common side that is 2 / 3 of the length of the common side and L-shaped third unit frames 54c having two sides common to the first unit frames 54a and a short side intersecting the common side that is 2 / 3 of the length of the common side are lined up without gaps along the side edges of the group of the second unit frames 54b and the third unit frames 54c, and diamond-shaped fourth unit frames 54d having one side that is 2 / 3 of the length of the first unit frame 54a are lined up without gaps along the side edges of the group of the second unit frames 54b and the third unit frames 54c. In this case, the area of ​​the unit frame 54 of the groove 53 is 4 / 9 at minimum, with the maximum being 1, which is a smaller change compared to the two examples described later. However, this change is preferable in terms of suppressing deformation due to the elastic member at the end of the absorbent body 56 on the waist opening WO side while maintaining the flexibility of the absorbent body 56.

[0082] The pattern of the grooves 53 in the edge region 56E of the example shown in Fig. 12 is also a diagonal lattice pattern. In this pattern, the diamond-shaped first unit frame 54e having the largest area is lined up without gaps in the center of the width direction WD, and along the side edge of the group of the first unit frames 54e, diamond-shaped second unit frames 54f each having a side length 1 / 2 that of the first unit frame 54e and L-shaped third unit frames 54g each having two long sides the same as that of the first unit frame 54e and four short sides 1 / 2 that of the first unit frame 54e are lined up without gaps, and along the side edge of the third unit frame 54g, diamond-shaped second unit frames 54f each having a side length 1 / 2 that of the first unit frame 54e are lined up without gaps. In this case, the maximum area of ​​the unit frames 54e-g is 1 / 4 at minimum.

[0083] The pattern of the grooves 53 in the edge region 56E in the example shown in Fig. 13 is also a diagonal lattice pattern. In this pattern, the diamond-shaped first unit frame 54h having the largest area is lined up without gaps in the center in the width direction WD, diamond-shaped second unit frames 54i each having a side length 1 / 2 that of the first unit frame 54h are lined up without gaps along the side edge of the group of the first unit frames 54h, and diamond-shaped third unit frames 54j each having a side length 1 / 3 that of the first unit frame 54h are lined up without gaps along the side edge of the group of the second unit frames 54i. In this case, the area of ​​the unit frames 54h-j is 1 / 9 at minimum when the maximum area is 1.

[0084] According to the findings of the present inventors, when the distance 56d between the elastic member closest to the edge region 56E of the absorbent body 56 and the edge region 56E in the front-rear direction LD is within 15 mm (particularly within 10 mm), the end of the absorbent body 56 on the waist opening WO side is particularly likely to deform. In this case, if a test specimen obtained by cutting a portion of the continuous stretchable band A2 from the edge region 56E of the absorbent body 56 to 15 mm toward the waist opening WO side from one side seal 12A to the other side seal 12A is stretched to 90% of the total width in the developed state and then contracted to 70% of the total width in the developed state, the end of the absorbent body 56 on the waist opening WO side is more likely to deform if the contraction force is 0.4 N or more (more preferably 0.5 to 1.5 N). Therefore, in these cases, it is preferable to increase the rigidity of the edge region 56E stepwise or continuously from the center of the absorbent body 56 in the width direction WD toward both side edges of the absorbent body 56 by changing the pattern of the grooves 53 described above. In addition, if these conditions are met in either the front or back body parts but not in the other body part, the rigidity of the edge region 56E in one body part can be increased stepwise or continuously from the center of the width direction WD of the absorbent body 56 toward both side edges of the absorbent body 56 by changing the pattern of the grooves 53 as described above, and the rigidity of the edge region 56E in the other body part can be not increased stepwise or continuously from the center of the width direction WD of the absorbent body 56 toward both side edges of the absorbent body 56 by changing the pattern of the grooves 53 as described above (i.e., grooves 53 are formed in a constant pattern in the width direction WD or no grooves 53 are formed at all).

[0085] <Experimental Example> 1 to 7, sample A (pattern shown in Figs. 9 to 11) and sample B (a diagonal lattice pattern in which the same unit frame 54 as the largest unit frame 54a of sample A is repeated throughout the absorbent body 56) were produced, which are common to both pants-type disposable diapers shown in Figs. 1 to 7 except for the pattern of the grooves 53. As a result, as shown in Fig. 14(a) in the natural length state, in sample A, deformation by the elastic member 15 at the end of the waist opening WO side of the absorbent body 56 was suppressed, whereas in sample B, as shown in Fig. 14(b) in the natural length state, both corners of the absorbent body 56 on the waist opening WO side selectively contracted in the width direction WD, and the middle part in the width direction WD at the end of the absorbent body 56 on the waist opening WO side hardly contracted, and the middle part in the width direction WD at the end of the absorbent body 56 on the waist opening WO side was bulging out towards the back side (outer surface side).

[0086] <Explanation of terms used in the specification> As used herein, the following terms have the following meanings unless otherwise specified in the specification.

[0087] The "front-rear direction" refers to the direction indicated by the symbol LD in the drawing (longitudinal direction), and the "width direction" refers to the direction indicated by the symbol WD in the drawing (left-right direction), with the front-rear direction and the width direction being perpendicular to each other.

[0088] "Front side" means the side closest to the wearer's skin when worn, and "back side" means the side away from the wearer's skin when worn.

[0089] "Front" means the side closest to the wearer's skin when worn, and "back" means the side away from the wearer's skin when worn.

[0090] "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.

[0091] "Gel strength" is measured as follows: 1.0g of superabsorbent polymer is added to 49.0g of artificial urine (a mixture of urea: 2wt%, sodium chloride: 0.8wt%, calcium chloride dihydrate: 0.03wt%, magnesium sulfate heptahydrate: 0.08wt%, and ion-exchanged water: 97.09wt%) and stirred with a stirrer. The resulting gel is left in a thermo-hygrostat at 40℃ x 60%RH for 3 hours, then returned to room temperature, and the gel strength is measured with a card meter (I.techno Engineering: Curdmeter-MAX ME-500).

[0092] - "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%. From the test piece that has reached a constant weight, a sample template (100mm x 100mm) is used to cut out a sample measuring 100mm x 100mm. The weight of the sample is measured and multiplied by 100 to calculate the weight per square meter, which is the basis weight.

[0093] The "thickness" of thick members such as the absorber 56, the absorbent element 50, the bottom 51 of the groove, etc. is measured using a thickness gauge made by Ozaki Manufacturing Co., Ltd. (Peacock, dial thickness gauge, model H (measurement range 0 to 10 mm, measurement area circular terminal with diameter of 10 mm, measurement force approximately 1.7 N, pressure approximately 21.7 KPa)) with the sample and the thickness gauge held horizontally.

[0094] The "thickness" of thin sheets such as nonwoven fabrics was 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: 2cm 2 The measurement is performed automatically under the following conditions.

[0095] The water absorption is measured according to JIS K7223-1996 "Test method for water absorption of superabsorbent resins".

[0096] The water absorption rate is the "time to the end point" when 2g of superabsorbent polymer and 50g of physiological saline are used and the test is performed in accordance with JIS K7224-1996 "Test method for water absorption rate of superabsorbent polymers."

[0097] "Unfolded state" means a flat, unfolded state without contraction (including any contraction, such as contraction due to elastic members) or sagging.

[0098] "Maximum elongation" refers to the maximum elongation in the stretch direction in the stretch region (i.e. the elongation at the elastic limit, which is equal to the elongation in the unfolded state), and is expressed as a percentage of the unfolded length, with the natural length being 100%.

[0099] *Unless otherwise specified, the dimensions of each part refer to the dimensions in the unfolded state, not in the natural length state.

[0100] If no specification is given regarding the environmental conditions for a test or measurement, the test or measurement shall be carried out 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%). [Industrial Applicability]

[0101] The present invention can be used in pants-type disposable wearing articles such as the pants-type disposable diaper described above. [Explanation of symbols]

[0102] Reference Signs List 11...liquid-impermeable sheet, 12A...side seal, 12B...rear exterior body, 12F...front exterior body, 12H...inner sheet layer, 12S...outer sheet layer, 12X...non-stretchable region, 13...cover nonwoven fabric layer, 14...buttocks cover portion, 15...lower waist elastic member, 16...buttocks cover elastic member, 17...waist elastic member, 30...top sheet, 50...absorbent element, 51...bottom, 52...non-compressible portion, 53 ... groove, 54 ... unit frame, 56 ... absorbent body, 56E ... edge region, 56M ... maximum width portion, 56N ... minimum width portion, 56V ... widened portion, 58 ... wrapping sheet, 60 ... side flap, 61 ... surface portion, 62 ... back surface portion, 64 ... liquid impermeable sheet layer, 65 ... portion without nonwoven fabric, 66 ... side nonwoven fabric, 66r ... folded portion, 67 ... fixing portion, 70 ... side non-stretchable region, 80 ...flat gather region, 200...inner body, 201...fixing region, 631-633...gathered elastic member, 631...first gathered elastic member, 632...second gathered elastic member, 633...third gathered elastic member, A1...intermittent stretch band, A2...continuous stretch band, B...back body, BT...back waist portion, F...front body, FT...front waist portion, HM1...first hot melt adhesive, HM2...second hot melt adhesive hot melt adhesive, HM3...third hot melt adhesive, L...middle region, LD...front to back direction, M...crotch portion, T...torso region, U...lower waist portion, W...waist portion, WD...width direction, WO...waist opening, d1...first distance, d2...second distance, d3...third distance, w1...first distance, w2...second distance, w3...width direction dimension of fixing portion, w4...third distance, w5...fourth distance.

Claims

1. an exterior body having a front waist portion, a rear waist portion, and side seals formed by joining both side portions of the front waist portion and the rear waist portion; An inner body extending from a front waist portion through a crotch portion to a rear waist portion; a waist opening formed by a front edge of the front waist portion and a rear edge of the rear waist portion; and leg openings provided on both sides of the interior body, The exterior body has a fixing region where the interior body is fixed to at least the front waist circumference portion and the rear waist circumference portion, the inner body has an absorbent body continuing from a position overlapping with the front waistband portion to a position overlapping with the rear waistband portion, the absorbent body has an edge region including an edge on the waist opening side and an entire widthwise portion adjacent to the crotch side thereof, and the entire edge region is located in a fixing region of the inner body and is fixed to the outer body, a first region of the front waistband and the rear waistband, which consists of a portion overlapping the absorbent body and a portion between the absorbent body and the side seal, is an intermittent elastic band having a non-elastic region provided at least in the middle of the portion overlapping the absorbent body in the width direction and an elastic region provided between the non-elastic region and each of the side seals, and a second region located between the intermittent elastic band and the waist opening is a continuous elastic band in which an elastic region continues in the width direction from one of the side seals to the other of the side seals, a pants-type disposable wearing article, wherein the elastic regions of the intermittent elastic band and the continuous elastic band incorporate elastic members and are stretchable between a natural length state in which the elastic members contract in the width direction and a stretched state in which the elastic members stretch in the width direction; A groove having a bottom portion that is recessed from the surface of the absorbent body into the absorbent body and compressed in the thickness direction is provided in a continuous pattern in the width direction over the entire width direction of the edge region, In the edge regions, from the center of the absorbent body in the width direction toward both side edges of the absorbent body, the thickness of the bottom of the groove is constant and the area ratio of the bottom of the groove increases, the area ratio of the bottom of the groove is constant and the thickness of the bottom of the groove decreases, or the area ratio of the bottom of the groove increases and the thickness of the bottom of the groove decreases. A pants-type disposable wearing article.

2. the edge region is a region in which the grooves are continuous in a lattice pattern, a thickness and a width of a bottom of the groove in the edge region are constant, and an area of ​​a unit frame formed of the groove in the edge region is gradually reduced from a center in a width direction toward both side edges.

2. The pants-type disposable wearing article according to claim 1.

3. The elastic members in the continuous stretchable band are elongated elastic members that are attached at intervals in the front-rear direction and extend along the width direction, The distance between the elongated elastic member closest to the edge region of the absorbent body and the edge region in the front-rear direction is within 15 mm.

3. The pants-type disposable wearing article according to claim 1 or 2.

4. A specimen obtained by cutting out a portion of the continuous stretchable band from the edge region of the absorbent body to the waist opening side by 15 mm from one side seal to the other side seal is stretched to 90% of the total width in the expanded state, and then contracted to 70% of the total width in the expanded state, and the contraction force is 0.4 N or more.

4. The pants-type disposable wearing article according to claim 3.

5. The absorbent body is made of one or more layers formed by mixing and accumulating pulp fibers and highly absorbent polymer particles, The basis weight of the pulp fiber in the absorbent body is 80 to 450 g / m ２ and the weight ratio of pulp fibers to superabsorbent polymer particles in the absorbent body is 20:80 to 80:20; The maximum thickness of the absorbent body is 1 to 20 mm, The thickness of the bottom portion is 5 to 40% of the maximum thickness of the absorbent body. The width of the bottom is 1 to 3 mm.

3. The pants-type disposable wearing article according to claim 1 or 2.

6. The grooves are formed in a diagonal lattice shape including a first portion inclined at 40 to 60 degrees clockwise in a plan view with respect to the front-rear direction and a second portion inclined at 40 to 60 degrees counterclockwise in a plan view with respect to the front-rear direction.

3. The pants-type disposable wearing article according to claim 1 or 2.

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