Pants-type disposable wear

Abstract

To reduce an influence of a leg motion on a side part of an absorbent body by single plane surface gathers.SOLUTION: A width of a side flap 60 is 0.1-0.5 times of a maximum width of an absorbent body 56. The side flap 60 includes: a first gather elastic member 631 disposed sideways from a side edge of a maximum width part 54 of the absorbent body 56 with a first interval d1; a second gather elastic member 632 disposed on a side part of the first gather elastic member with a second interval d2; and third gather elastic members 633 disposed repetitively on a side part of the second gather elastic member with a third interval d3. The second interval d2 is 1.5-5 times as large as the third interval d3. The first interval d1 is 0.3-0.8 times as large as the second interval d2. A thickness of the first gather elastic member 631 is 0.95-1.05 times as large as a thickness of the second gather elastic member 632 and the third gather elastic member 633. An expansion rate of the first gather elastic member 631 is 1.2-1.5 times as large as an expansion rate of the second gather elastic member 632 and a third expansion rate.SELECTED DRAWING: Figure 8

Description

[Technical Field]

[0001] The present invention relates to a pants-type disposable wearing article having flat gathers on both sides of the width of an inner body. [Background technology]

[0002] Pant-type disposable wearing articles such as pant-type disposable diapers and pant-type sanitary napkins generally comprise an outer body that forms at least the waist-circumference portions of a front body and a back body, and an inner body that includes an absorbent and is attached to the outer body so as to extend from the front body to the back body. Side seals are formed by joining both side edges of the outer body of the front body and both side edges of the outer body of the back body, thereby forming a waist opening and a pair of left and right leg openings.

[0003] The waist region of the outer garment is defined as a front-to-back range having side seals (the range from the waist opening to the upper ends of the leg openings) and is provided with elastic members to provide widthwise stretchability, which allows the waist region to fit well to the wearer's body surface.

[0004] Furthermore, in pants-type disposable wearable articles, it is common for side gathers to be provided on both widthwise sides of the inner body to fit the inner thighs of the wearer, in order to improve the fit around the legs and prevent so-called side leakage (see, for example, Patent Documents 1 to 3).

[0005] Various structures of side gathers have been proposed in the past. For example, gathers that rise from the sides of the inner body to the front are generally called three-dimensional gathers and are excellent at preventing leakage. In contrast, gathers formed by side flaps that extend to the sides of the absorbent body (without being folded back to the front) are generally called flat gathers and are often used in combination with three-dimensional gathers.

[0006] Furthermore, particularly for simple, low-cost products, some have been proposed that have flat gathers but no three-dimensional gathers (see, for example, Patent Documents 1 to 3). Such single flat gathers have a first portion that, when worn, extends obliquely upward from the side edge of the absorbent body toward the base of the wearer's inner thigh in the crotch area, and a second portion that extends obliquely downward from the tip (distal end) of the first portion along the inner thigh. An elongated gathered elastic member is attached to the second portion along the front-to-rear direction, and the second portion contracts in the front-to-rear direction together with the gathered elastic member in its natural length, and is also extensible in the front-to-rear direction together with the gathered elastic member. In other words, when worn, the second portion of the flat gathers is pressed against the inner thigh by the contractile force of the gathered elastic member.

[0007] However, conventional single flat gathers have the problem that, due to the lack of support provided by three-dimensional gathers, when the second part moves in response to leg movements such as when walking, that movement is easily transmitted to the absorbent body via the first part. If the movement of the second part is transmitted to the absorbent body via the first part, there is a risk that the sides of the absorbent body will collapse. Furthermore, if the sides of the absorbent body collapse, the support of the flat gathers will weaken, and there is a risk that the fit of the second part will deteriorate. Therefore, improvements are desired for conventional single flat gathers. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Patent No. 5303689 [Patent Document 2] Patent No. 5400982 [Patent Document 3] Patent No. 6986097 [Patent Document 4] Japanese Patent Publication No. 2021-000236 Summary of the Invention [Problem to be solved by the invention]

[0009] Therefore, a main object of the present invention is to reduce the influence of leg movement on the side of the absorbent body due to a single plane gather. [Means for solving the problem]

[0010] The following pants-type disposable wearing article has solved the above problems. <First aspect> An integrated outer body extending from the front body to the back body, or an outer body provided separately on the front body and the back body, An inner body attached to the middle of the outer body in the width direction from a position forward of the crotch area to a position rearward of the crotch area; A pair of side seals formed by joining both side portions of the exterior body in the front body and both side portions of the exterior body in the back body, respectively; a waist opening formed by the front edge of the front body and the rear edge of the back body; leg openings provided on both sides of the interior body, the inner body has an absorbent body that continues from a position in front of the crotch region to a position in back of the crotch region, The absorber has maximum width portions on the front side of the crotch region and on the rear side of the crotch region, A pair of side flaps extend from the side edges of the absorbent body to both sides in the width direction on both sides of the inner body, and extend in the front-rear direction from the front end to the rear end of the inner body, the side flaps have planar gathers that extend from the sides of the maximum width portion of the absorber on the front side of the crotch region to the sides of the maximum width portion of the absorber on the rear side of the crotch region, The plane gathers are portions incorporating elongated gathered elastic members along the front-to-rear direction, and are contracted in the front-to-rear direction together with the gathered elastic members, and are also extensible in the front-to-rear direction together with the gathered elastic members, Does not have three-dimensional gathers that rise up on the front side A pants-type disposable wearable article; The width of the side flaps is 0.1 to 0.5 times the maximum width of the absorbent body, The gathered elastic members are comprised of a first gathered elastic member attached laterally at a first interval from the side edge of the widest part of the absorbent body, a second gathered elastic member attached laterally at a second interval from the first gathered elastic member, and a third gathered elastic member attached repeatedly to the side edge of the side flap at a third interval from the second gathered elastic member, the first gathered elastic member has a first thickness and is attached to the side flap with a first elongation rate; the second gathered elastic member has a second thickness and is attached to the side flap with a second elongation rate; the third gathered elastic member has a third thickness and is attached to the side flap with a third elongation rate; the second interval is 1.5 to 5 times the third interval, the first interval is 0.3 to 0.8 times the second interval; the first elongation rate is 0.95 to 1.05 times the second elongation rate and the third elongation rate, and the first thickness is 1.2 to 1.5 times the second elongation rate and the third thickness, or the first thickness is 0.95 to 1.05 times the second elongation rate and the third thickness, and the first elongation rate is 1.2 to 1.5 times the second elongation rate and the third elongation rate, or the first thickness is 1.2 to 1.5 times the second elongation rate and the third thickness, and the first elongation rate is 1.2 to 1.5 times the second elongation rate and the third elongation rate, A pants-type disposable wearing article characterized by:

[0011] (Action and effect) In this pants-type disposable wearable article, the side flaps having flat gathers are sufficiently wide, a first gathered elastic member is provided near the absorbent body, a second gathered elastic member is provided at a position some distance to the side of the absorbent body, and third gathered elastic members are repeatedly provided at close intervals up to the side edges of the side flaps. The force required to stretch the first gathered elastic member provided near the absorbent body is stronger than that required for the second gathered elastic member and the third gathered elastic member. As a result, the proper wearing state is as follows: In the crotch area, the portion between the side edge of the absorbent body and the second gathered elastic member forms a first portion that extends diagonally upward toward the base of the wearer's inner thigh, and the portion from the second gathered elastic member to the side edge of the side flap forms a second portion that extends diagonally downward along the inner thigh. The first portion is lifted up more strongly by the first gathered elastic member than the second portion, making it less likely to move. The second portion, located at a position some distance from the first gathered elastic member, fits closely to the inner thigh, using the first gathered elastic member as support. Therefore, even if the second part moves in response to leg movement, the part between the first gathered elastic member and the second gathered elastic member deforms and provides a cushioning effect, making it less likely that the movement of the second part will be transmitted to the absorbent body via the first part, thereby reducing the risk of the sides of the absorbent body collapsing.

[0012] <Second aspect> the absorber has a minimum width portion in the crotch area, and has widening portions whose widths gradually increase from the minimum width portion to a maximum width portion on the front side and to a maximum width portion on the rear side, The widthwise distance between the side edge of the minimum width portion of the absorbent body and the first gathered elastic member is 1.1 to 1.5 times the second distance. A pants-type disposable wearing article according to a first embodiment.

[0013] (Action and effect) If the widthwise distance between the side edge of the absorbent body's minimum width portion and the first gathered elastic member is too wide, the portion between the side edge of the absorbent body's minimum width portion and the first gathered elastic member will be likely to sink significantly toward the back side, causing body waste to accumulate on the side flaps and making it easier for toes to get caught when worn. Therefore, the configuration of the second aspect is preferable.

[0014] <Third aspect> The portion located between the first gathered elastic member and the second gathered elastic member has a three-layer structure including a surface nonwoven fabric layer, a back nonwoven fabric layer, and a liquid-impermeable film sandwiched therebetween, the surface nonwoven fabric layer and the liquid-impermeable film are bonded together via a first hot-melt adhesive; the back surface nonwoven fabric layer and the liquid-impermeable film are bonded together via a second hot melt adhesive; the surface nonwoven fabric layer and the back nonwoven fabric layer each have a bending resistance, measured by the 41.5° cantilever method defined in JIS L 1913:2010, of 0.2 to 2.2 mN cm in the front-to-rear direction and 0.05 to 0.5 mN cm in the width direction; The liquid-impermeable film has a bending resistance of 0.006 to 0.05 mN cm in the longitudinal direction (LD) and 0.006 to 0.05 mN cm in the width direction (WD) as measured by the 41.5° cantilever method specified in JIS L 1913:2010, The amount of the first hot melt adhesive applied is 1 to 10 g / m 2 and The amount of the second hot melt adhesive applied is 1 to 10 g / m 2 That is, A pants-type disposable wearing article according to the first or second aspect.

[0015] (Action and effect) The portion between the first gathered elastic member and the second gathered elastic member is a portion that exerts a cushioning effect, and therefore it is preferable that the portion has low rigidity as in this embodiment.

[0016] <Fourth aspect> the absorber has a minimum width portion in the crotch area, and has widening portions whose widths gradually increase from the minimum width portion to a maximum width portion on the front side and to a maximum width portion on the rear side, When the back body is placed on a horizontal surface with the back portion facing downwards, and only the outer body is unfolded along the flat surface from its natural length, and viewed from above, Among the outline lines of the crotch region, an acute-angle side crossing angle α formed by an imaginary line connecting the positions of the side edges of the absorber and the positions of the first gathered elastic members and the front-to-back direction is 15 to 40 degrees, an acute-angle side crossing angle γ formed by an imaginary line connecting the positions of adjacent third gathered elastic members and the front-to-back direction is 50 to 90 degrees, and an acute-angle side crossing angle β formed by an imaginary line connecting the positions of the first gathered elastic members and the positions of the second gathered elastic members and the front-to-back direction satisfies the relationship α<β<γ. The pants-type disposable wearing article according to any one of the first to third aspects.

[0017] (Action and effect) The configuration of this embodiment is preferable because it provides a more excellent buffering effect. [Effects of the Invention]

[0018] As described above, the present invention provides advantages such as reducing the influence of leg movement on the sides of the absorbent body due to the single plane gathers. [Brief explanation of the drawings]

[0019] [Figure 1] 1 is a plan view showing the surface of a pants-type disposable diaper in an unfolded state. FIG. [Figure 2] 1 is a plan view showing the underside of a pants-type disposable diaper in an unfolded state. FIG. [Figure 3] 3 is a cross-sectional view of FIG. 1 taken along line 3-3. [Figure 4] 4 is a cross-sectional view taken along line 4-4 of FIG. 1. [Figure 5] 5 is a cross-sectional view taken along line 5-5 of FIG. 1. [Figure 6]FIG. 2 is a plan view showing the surface of the inner body. [Figure 7] 1 is a perspective view of a pants-type disposable diaper, seen from the front and diagonally below. FIG. [Figure 8] FIG. 2 is a cross-sectional view of a main part showing the attached state. [Figure 9] FIG. 10 is a front view schematically showing the inclination of each part of the side flap. DETAILED DESCRIPTION OF THE INVENTION

[0020] 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 accompanying drawings. Note that adjacent components in the thickness direction may be fixed or joined as needed, in addition to the fixed or joined portions described below, in the same manner as known diapers. The dotted areas in the cross-sectional view indicate adhesives such as hot-melt adhesives used as the fixing or joining means. Hot-melt adhesives can be applied by known methods, such as slot coating, continuous or dotted bead coating, spiral, Z-shaped, or wavy (regular or irregular) spray coating, or pattern coating (transfer of hot-melt adhesive using a relief printing method). Alternatively or in addition to this, hot-melt adhesive can be applied to the outer surface of the elastic member to fix 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 limitation is imposed on them. Material welding methods such as heat sealing and ultrasonic sealing can also be used to fix or join the components. 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 application such as a spiral, Z-shape, or wavy pattern can be suitably used. When applying to an area greater than the application width of a single nozzle, intermittent pattern application such as a spiral, Z-shape, or wavy pattern can be performed with or without gaps in the width direction. Material welding methods such as heat sealing and ultrasonic sealing can also be used to join the components.

[0021] Furthermore, as the nonwoven fabric in the following description, known nonwoven fabrics can be used as appropriate depending on the location 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 as well as core-sheath and other composite fibers), regenerated fibers (e.g., rayon or cupra), and natural fibers (e.g., cotton), and mixtures of these can also be used. To increase the flexibility of the nonwoven fabric, it is preferable to use crimped fibers as the constituent fibers. Furthermore, 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). Furthermore, nonwoven fabrics are generally classified into staple fiber nonwoven fabrics, long fiber nonwoven fabrics, spunbond nonwoven fabrics, meltblown nonwoven fabrics, spunlace nonwoven fabrics, thermal bond (air-through) nonwoven fabrics, needle-punched nonwoven fabrics, point-bond nonwoven fabrics, laminated nonwoven fabrics (including SMS nonwoven fabrics and SMMS nonwoven fabrics in which a meltblown layer is sandwiched between spunbond layers), etc. depending on the fiber length, sheet formation method, fiber bonding method, and laminated structure, and any of these nonwoven fabrics can be used.

[0022] 1 to 7 show an example of a pants-type disposable diaper. This pants-type disposable diaper 100 includes a rectangular front outer body 12F constituting a front waist-surrounding portion, a rectangular rear outer body 12B constituting a rear waist-surrounding portion, and an inner body 200 attached to the middle of the outer bodies 12F, 12B in the width direction WD so as to extend from the front outer body 12F through the crotch region M to the rear outer body 12B. Side seals 12A are formed by joining both sides of the front outer body 12F to both sides of the rear outer body 12B, and thereby an opening formed by the front and rear edges of the outer bodies 12F, 12B serves as a waist opening WO through which the wearer's waist is passed, 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 outer bodies 12F, 12B and the side edges of the inner body 200 serve as leg openings LO through which the legs are passed. The inner body 200 is a part that absorbs and retains excrement such as urine, and the outer bodies 12F, 12B are parts 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-back 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.

[0023] The pants-type disposable diaper 100 has a waist region T defined as the front-to-back range having the side seals 12A (the front-to-back range from the waist opening WO to the top ends of the leg openings LO), and an intermediate region L defined as the front-to-back range of the portion forming the leg openings LO (between the front-to-back region having the side seals 12A of the front body F and the front-to-back region having the side seals 12A of the back 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 portion and the rear waist portion, 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. Typically, when the front and rear waist regions have a boundary where the stretch stress in the width direction WD changes (e.g., where the thickness or elongation rate of the elastic member changes), the waist region W is the portion closer to the waist opening WO than the boundary closest to the waist opening WO. When no such boundary exists, the waist region W is the portion extending further toward the waist opening WO than the absorbent body 56 or inner body 200. Their front-to-rear lengths vary depending on the product size and can be determined as appropriate. For example, the waist region W may be 15 to 40 mm, and the lower waist region U may be 65 to 120 mm. Meanwhile, both side edges of the middle region L are constricted in a U-shape or curved shape to fit around the wearer's legs, and these are the areas into which the wearer's legs are inserted. As a result, the pants-type disposable diaper in its unfolded state has a generally hourglass shape overall.

[0024] (exterior body) As shown in the figure, the exterior bodies 12F, 12B are composed of a rectangular front exterior body 12F that forms at least the waistline of the front body F, and a rectangular back exterior body 12B that forms at least the waistline of the back body B. The front exterior body 12F and the rear exterior body 12B may not be continuous at the crotch side and may be spaced apart in the front-to-back direction LD (two-piece exterior type), or may be continuous from the front body F to the back body B (one-piece exterior type), although this is not shown. In the two-piece exterior type, the separation distance 12d in the front-to-back direction can be, for example, approximately 40 to 60% of the total length Y. In the figure, the lower edges of the front exterior body 12F and the rear exterior body 12B are linear and extend along the width direction WD, but the lower edge of at least one of the front exterior body 12F and the rear exterior body 12B may be curved to fit around the legs.

[0025] In a pants-type disposable diaper with a two-piece exterior, the inner body 200 is exposed between the front exterior body 12F and the rear exterior body 12B, and therefore, to prevent the liquid-impermeable film 11 from being 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, extending 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 and outer surfaces of the cover nonwoven fabric layer 13 can be bonded to their respective opposing surfaces via a hot melt adhesive. The nonwoven fabric used for the cover nonwoven fabric layer 13 can be selected appropriately from, for example, the same material as that of the exterior bodies 12F and 12B.

[0026] The front exterior body 12F and the rear exterior body 12B have a front waist portion and a rear waist portion that form the waist region T. In the example shown in Figures 1 and 2, the front-to-rear dimension of the rear exterior body 12B is longer than that of the front exterior body 12F, the front exterior body 12F does not have a portion corresponding to the middle region L, and the rear exterior body 12B has a buttocks covering portion 14 that extends from the waist region T toward the middle region L; however, the front exterior body 12F and the rear exterior body 12B may have the same dimension in the front-to-rear direction LD, and the front exterior body 12F and the rear exterior body 12B may not have a portion corresponding to the middle region L.

[0027] 3 to 5, the exterior bodies 12F, 12B are formed by joining 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, which will be described later, by a joining means such as a hot melt adhesive or welding. As shown in Fig. 5, the outer sheet layer 12S and the inner sheet layer 12H are formed by folding a single sheet material so that the fold is located on the waist opening side, or, although not shown, they can also be formed by bonding two sheets of sheet material together.

[0028] The sheet material used for the outer sheet layer 12S and the inner sheet layer 12H is not particularly limited, but nonwoven fabric is preferred. When nonwoven fabric is used, the basis weight per sheet is 10 to 30 g / m 2 It is preferable to set it to about this level.

[0029] To improve the fit around the waist of the wearer, the outer coverings 12F, 12B have elastic members 15-17 attached between the outer sheet layer 12S and the inner sheet layer 12H at a predetermined stretch rate, forming stretchable regions that stretch elastically in the width direction WD together with the elastic members 15-17. When in their natural length, the stretchable regions contract as the elastic members 15-17 contract, forming wrinkles or folds. When stretched in the longitudinal direction of the elastic members, they can be stretched to a predetermined stretch rate without wrinkles. The elastic members 15-17 can be elongated elastic members such as rubber threads (illustrated example), as well as known elastic members in strip, net, film, and other shapes, without any particular limitation. The elastic members 15-17 may be made of synthetic or natural rubber. The outer sheet layer 12S and the inner sheet layer 12H of the exterior bodies 12F, 12B can be bonded together, and the elongated elastic members 15-17 sandwiched therebetween can be secured using at least one of various application methods of hot melt adhesive and material welding, such as heat sealing or ultrasonic sealing. Since strongly securing the entire surfaces of the exterior bodies 12F, 12B impairs flexibility, it is preferable to either not secure or only weakly secure the elongated elastic members 15-17 in areas other than the adhesive bonded portions. In the illustrated example, hot melt adhesive is applied only to the outer peripheral surfaces of the elongated elastic members 15-17 using an application means such as a comb gun or a SureWrap nozzle, and then the elongated elastic members are sandwiched between the sheet layers 12S, 12H. This structure allows the elongated elastic members 15-17 to be secured to the sheet layers 12S, 12H and the sheet layers 12S, 12H together using only the hot melt adhesive applied to the outer peripheral surfaces of the elongated elastic members 15-17.

[0030] 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 region W of the outer bodies 12F, 12B at intervals in the front-to-rear direction and in a state stretched in the width direction at a predetermined stretch rate, forming a continuous elastic region throughout the width direction WD. Furthermore, one or more of the waist elastic members 17 arranged in the region adjacent to the lower waist region U may overlap the inner body 200, or may be provided on both sides of the width direction WD except for the central portion in the width direction that overlaps with the inner body 200. The waist elastic members 17 should have a thickness of 155-1880 dtex, particularly about 470-1240 dtex (in the case of synthetic rubber; in the case of natural rubber, a cross-sectional area of ​​0.05-1.5 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 1 / 4" thick (approximately 1 / 4" thick) at intervals of 2 to 12 mm, especially 3 to 7 mm, and the resulting elongation rate in the width direction WD of the waist portion W is preferably about 150 to 400%, especially about 220 to 320%. Furthermore, it is not necessary for the waist portion W to use elastic members of the same thickness or to have the same elongation rate all along the front-to-back direction LD, and for example, the thickness or elongation rate may be different in some areas.

[0031] In addition, between the outer sheet layer 12S and the inner sheet layer 12H in the lower-waist portion U of the outer bodies 12F, 12B, a plurality of lower-waist elastic members 15 made of elongated elastic members are attached at intervals in the front-to-rear direction and stretched in the width direction at a predetermined stretch rate, forming stretchable regions on both sides in the width direction WD except for the central part in the width direction that overlaps with the inner body 200. The lower-waist elastic members 15 are made of a material having a thickness of 155 to 1880 dtex, particularly about 470 to 1240 dtex (in the case of synthetic rubber, or a cross-sectional area of ​​0.05 to 1.5 mm in the case of natural rubber). 2 , especially 0.1 to 1.0 mm 2It is preferable to provide about 5 to 30 elastic threads of about 100 mm thick (approximately 1 / 2" thick) at intervals of 1 to 15 mm, especially 3 to 8 mm, and the resulting elongation rate in the width direction WD of the waist lower portion U is preferably about 200 to 350%, especially about 240 to 300%. Furthermore, it is not necessary for the waist lower portion U to use elastic members of the same thickness or have the same elongation rate all over its front-to-back direction LD, and thicknesses and elongation rates may vary in some areas.

[0032] In addition, 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 stretched in the width direction at a predetermined stretch rate on both sides in the width direction WD except for the width center portion overlapping with the interior body 200, forming stretchable regions on both sides in the width direction WD except for the width center portion overlapping with the interior body 200. The buttocks cover elastic members 16 have a thickness of 155 to 1880 dtex, particularly about 470 to 1240 dtex (in the case of synthetic rubber, or a cross-sectional area of ​​0.05 to 1.5 mm in the case of natural rubber). 2 , especially 0.1 to 1.0 mm 2 It is preferable to fix about 2 to 10 rubber threads (approximately 150 to 300%, particularly 180 to 260%) at intervals of 5 to 40 mm, particularly 5 to 20 mm, each with an elongation of 150 to 300%, particularly 180 to 260%.

[0033] As shown in the figures, if the lower-waist elastic members 15 and the buttocks-covering elastic members 16 are provided on both sides in the width direction WD except for part or all of the portion overlapping with the inner body 200, the inner body 200 will not shrink more than necessary in the width direction, and will not look bulky or have reduced absorbency. This type of structure includes not only cases where elastic members are present only on both sides in the width direction WD, but also cases where elastic members are present across the inner body 200 from one side to the other in the width direction, but where the elastic members are cut into small pieces in the middle or all of the widthwise portion overlapping with the inner body 200, as shown by reference symbol 12X in Figures 2 and 4, so that no contractile force acts on them (effectively equivalent to no elastic members being provided), and only both sides in the width direction WD are configured as contractile force acting portions. Of course, the arrangement of the waist lower elastic member 15 and buttocks covering elastic member 16 is not limited to the above example, and some or all of the waist lower elastic member 15 and buttocks covering elastic member 16 can be arranged across the inner body 200 from one side to the other side in the width direction so that an elastic force acts across the entire width direction, including the part that overlaps with the inner body 200.

[0034] (Interior body joint) The inner body 200 can be fixed to the outer bodies 12F, 12B by a joining method that uses material welding, such as heat sealing or ultrasonic sealing, or by a hot melt adhesive. In the illustrated example, the back surface of the inner body 200 is fixed to the inside surface of the outer bodies 12F, 12B via a hot melt adhesive. This inner body joint 201 can be provided over almost the entire overlapping area, as shown in Fig. 2, and can also be provided in a portion of the inner body 200 excluding both widthwise ends, for example.

[0035] (interior body) The inner body 200 may have any shape, but is rectangular in the illustrated example. 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 film 11, and an absorbent element 50 sandwiched between them. Reference numeral 60 denotes side flaps 60 having flat gathers.

[0036] (Top sheet) The top sheet 30 can be made of any liquid-permeable material, such as a perforated or non-perforated nonwoven fabric or a perforated plastic sheet, but when the top sheet 30 also serves as a covering material for the liquid-impermeable film 64, as in the example shown in Figures 3 and 4, a nonwoven fabric is preferred.

[0037] If both sides of the top sheet 30 in the width direction WD do not also serve as covering materials for the liquid-impermeable film 64 , the side edges of the absorbent element may be folded back to extend between the absorbent element 50 and the liquid-impermeable film 11 .

[0038] (middle seat) Although not shown, an intermediate sheet (also called a "second sheet") that has a faster liquid permeability rate than the top sheet 30 can be provided 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, improving the absorption performance of the absorbent body and preventing the phenomenon of absorbed liquid "flowing back" from the absorbent body. The intermediate sheet can also be omitted.

[0039] (Liquid-impermeable film) The material of the liquid-impermeable film 11 provided on the back side of the absorbent body 56 is not particularly limited, but examples include plastic films made of polyolefin resins such as polyethylene and polypropylene. A liquid-impermeable and moisture-permeable material, which has been favored in recent years from the viewpoint of preventing stuffiness, is preferably used for the liquid-impermeable film 11. A widely used moisture-permeable plastic film is a microporous plastic film obtained by kneading an inorganic filler into a polyolefin resin such as polyethylene or polypropylene, forming the sheet, and then stretching it uniaxially or biaxially.

[0040] The liquid-impermeable film 11 can be configured to extend into the side flaps to improve the waterproofness of the flat gathers, as in the examples 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 edges of the absorbent element 50 and extend between the absorbent element 50 and the top sheet 30.

[0041] (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.

[0042] (absorber) The absorbent body 56 can be formed from a fiber assembly. This fiber assembly can be made by stacking staple fibers such as cotton-like pulp or synthetic fibers, or it can be made from a filament assembly obtained by opening a tow (fiber bundle) of synthetic fibers such as cellulose acetate as needed. When cotton-like pulp or staple fibers are stacked, 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 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.

[0043] It is preferable that superabsorbent polymer particles are mixed into the fiber aggregate. The term "superabsorbent polymer particles" includes not only "particles" but also "powder." The superabsorbent polymer particles used in this type of disposable diaper can be used as is. For example, it is preferable that the percentage of particles remaining on a 500 μm standard sieve (JIS Z8801-1:2006) after sieving (shaking for 5 minutes) is 30% by weight or less, and it is also preferable that the percentage of particles remaining on a 180 μm standard sieve (JIS Z8801-1:2006) after sieving (shaking for 5 minutes) is 60% by weight or more.

[0044] The material for 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 polymers") . Examples of superabsorbent polymer particles include starch-based, cellulose-based, and synthetic polymer-based materials, such as 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 or granular form, but other shapes can also be used.

[0045] 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.

[0046] 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.

[0047] 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, it is generally in the range of 50 to 350 g / m 2 The polymer weight can be 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.

[0048] There are no particular limitations on the ratio of fibers to superabsorbent polymer particles in the absorbent body 56, but a weight ratio of fibers to superabsorbent polymer particles of 50:50 to 20:80 can result in a thinner absorbent body 56 when compared for the same area and the same absorption capacity. In this case, there are no particular limitations on the thickness 56t of the absorbent body 56, but it can be 3 to 15 mm.

[0049] The absorber 56 continues from a position in front of the crotch region M to a position behind the crotch region M, and in the illustrated example, preferably continues from the front exterior body 12F to the rear exterior body 12B. Note that the symbol 56X indicates the maximum width (total width) of the absorber 56.

[0050] In order to ensure an adequate amount of absorption in the crotch area M, it is preferable that the absorbent body 56 has a substantially rectangular shape. However, as shown in FIGS. 1 and 2, if the absorbent body 56 has a minimum width portion 52 in the crotch area M and widened portions 53 that gradually widen from the minimum width portion 52 to the maximum width portion 54 on the front side of the crotch area M and to the maximum width portion 54 on the rear side of the crotch area M, the minimum width portion 52 and the widened portion 53 may be formed. 53 A constricted portion 52 consisting of 53 This is preferable because it improves the fit around the inner thighs. In the latter case, to ensure a sufficient absorption amount in the crotch region M, it is preferable that width 52w of the narrowest part of absorber 56 in the crotch region M be 0.8 times or more the maximum width 56X of absorber 56. It is also preferable that the dimension of constricted portions 52, 53 in the front-to-rear direction be approximately 20 to 30% of total length Y of the product.

[0051] In addition, the crotch area M refers to the area where the absorbent body 56 has the above-mentioned constricted portions 52, 53. 53 The absorbent body 56 has a constricted portion 52, 53 However, if the outer shape in the unfolded state has a narrowed portion as in the illustrated example, it means the range in the front-to-back direction LD that has the narrowed portion of this outer shape (in the illustrated example, between the front outer body 12F and the rear outer body 12B), and if there are no narrowed portions, it means the part that is located in the center of the front-to-back direction LD and whose dimension in the front-to-back direction LD is 20 to 30% of the total length Y of the product.

[0052] (packaging sheet) When using a packaging sheet 58, the material can be a liquid-permeable material such as tissue paper, especially crepe paper, nonwoven fabric, polylaminated nonwoven fabric, or a sheet with small holes. However, it is preferable that the sheet does not allow the superabsorbent polymer particles to escape. When using nonwoven fabric instead of crepe paper, hydrophilic SMS nonwoven fabric (SMS, SSMMS, etc.) is particularly suitable, and polypropylene, polyethylene / polypropylene composite material, etc. can be used. The basis weight is 5 to 40 g / m 2 , especially 10 to 30 g / m 2 It is preferable that:

[0053] The packaging structure of the packaging sheet 58 can be determined as appropriate, but from the standpoint of ease of manufacturing 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 extending beyond the front and rear of the absorbent body 56, and to crush these extending portions in the front and rear directions and join them with a joining means such as a hot melt adhesive.

[0054] (Side flap) As shown in FIGS. 1 to 4 and 6, the side flaps 60 are a pair of portions extending from the side edges of the absorber 56 on both sides in the width direction WD, and each extends in the front-to-back direction LD from the front end to the rear end of the inner body 200. Characteristically, the side flaps 60 have planar gathers that extend from the sides of the widest portion 54 of the absorber 56 in front of the crotch region M to the sides of the widest portion 54 of the absorber 56 behind the crotch region M. The planar gathers incorporate elongated gather elastic members 631-633 that extend along the front-to-back direction LD, and are contracted in the front-to-back direction LD together with the gather elastic members 631-633, while also being stretchable in the front-to-back direction LD together with the gather elastic members 631-633. Furthermore, this pants-type disposable diaper does not have upright gathers that rise to the front side, and only has planar gathers of the side flaps 60.

[0055] It is desirable that the width of the side flaps 60 be sufficiently wide to reduce the effect of leg movement on the sides of the absorber 56. Therefore, the width 60w of the side flaps 60 is preferably 0.1 to 0.5 times the maximum width 56X of the absorber 56, more preferably 0.3 to 0.5 times, and particularly preferably 0.4 to 0.5 times. The gathered elastic members 631-633 are comprised of a first gathered elastic member 631 attached laterally from the side edge of the widest portion 54 of the absorber 56 at a first distance d1, a second gathered elastic member 632 attached laterally from the first gathered elastic member 631 at a second distance d2, and a third gathered elastic member 633 attached repeatedly from the second gathered elastic member 632 at a third distance d3 to the side edge of the side flap 60 (i.e., no other elastic members are included), and it is preferable that the second distance d2 is 1.5 to 5 times the third distance d3 and the first distance d1 is 0.3 to 0.8 times the second distance d2. It is more preferable that the second distance d2 is 1.5 to 2.5 times the third distance d3 and the first distance d1 is 0.3 to 0.7 times the second distance d2. More specifically, when used for babies and small children, the width of the side flaps 60 is preferably 30 to 50 mm, and particularly preferably 40 to 50 mm.

[0056] Furthermore, when the first gathered elastic member 631 has a first thickness and is attached to the side flap 60 at a first stretch rate, the second gathered elastic member 632 has a second thickness and is attached to the side flap 60 at a second stretch rate, and the third gathered elastic member 633 has a third thickness and is attached to the side flap 60 at a third stretch rate, (a1) the first stretch rate is equal to or greater than the second stretch rate and the third stretch rate. and the first thickness is 0.95 to 1.05 times the elongation rate of the second and third thicknesses and 1.2 to 1.5 times the elongation rate of the second and third thicknesses, or (b1) the first thickness is 0.95 to 1.05 times the elongation rate of the second and third thicknesses and the first elongation rate is 1.2 to 1.5 times the elongation rate of the second and third thicknesses, or (c1) the first thickness is 1.2 to 1.5 times the elongation rate of the second and third thicknesses and the first elongation rate is 1.2 to 1.5 times the elongation rate of the second and third thicknesses. More preferably, (a2) the first elongation rate is 0.95 to 1.05 times the second and third elongation rates and the first thickness is 1.3 to 1.4 times the second and third thicknesses, or (b2) the first thickness is 0.95 to 1.05 times the second and third thicknesses and the first elongation rate is 1.3 to 1.5 times the second and third elongation rates, or (c2) the first thickness is 1.3 to 1.4 times the second and third thicknesses and the first elongation rate is 1.3 to 1.5 times the second and third elongation rates.

[0057] Long, thin elastic members such as rubber threads or rubber strips can be used as the gathered elastic members 631 to 633. When rubber threads are used, the thickness of the first to third threads is preferably 400 to 950 dtex, and more preferably 470 to 780 dtex. The elongation percentages of the first to third threads are preferably 200 to 320%, and more preferably 260 to 320%.

[0058] In this way, when the width of the side flap 60 having plane gathers is ensured to be sufficiently wide, the first gathered elastic member 631 is provided near the absorbent body 56, the second gathered elastic member 632 is provided at a position spaced some distance to the side from there, and the third gathered elastic member 633 is repeatedly provided at narrow intervals up to the side edge of the side flap 60, and the force required to stretch the first gathered elastic member 631 provided near the absorbent body 56 is stronger than that of the second gathered elastic member 632 and the third gathered elastic member 633, the appropriate wearing state will be as shown in Figures 7 and 8. That is, in the crotch region M, the portion between the side edge of the absorbent body 56 and the second gathered elastic member 632 forms a first portion 60A extending obliquely upward toward the base of the wearer's inner thigh, and the portion from the second gathered elastic member 632 to the side edge of the side flap 60 forms a second portion 60B extending obliquely downward along the inner thigh. Here, the first portion 60A is lifted up more strongly by the first gathered elastic member 631 than the second portion 60B, making it difficult to move, and the second portion 60B, which is positioned a certain distance away from the first gathered elastic member 631, comes into close contact with the inner thigh, using the first gathered elastic member 631 as support. Therefore, even if the second portion 60B moves in response to the movement of the leg, the portion between the first gathered elastic member 631 and the second gathered elastic member 632 deforms and exhibits a cushioning effect, making it difficult for the movement of the second portion 60B to be transmitted to the absorber 56 via the first portion 60A, thereby reducing the risk of the sides of the absorber 56 collapsing.

[0059] As shown in the illustrated example, when the absorber 56 has a minimum width portion 52 in the crotch region M and has widened portions 53 that gradually widen from the minimum width portion 52 to the front maximum width portion 54 and the rear maximum width portion 54, if the distance d4 in the width direction WD between the side edge of the minimum width portion 52 of the absorber 56 and the first gathered elastic member 631 is too wide, the portion between the side edge of the minimum width portion 52 of the absorber 56 and the first gathered elastic member 631 is likely to be significantly recessed on the back side, causing body waste to accumulate on the side flaps 60 or making it easy for toes to get caught when worn. It is preferable that the distance d4 in the width direction WD between the side edge of the minimum width portion 52 of the absorber 56 and the first gathered elastic member 631 be 1.1 to 1.5 times, and particularly 1.1 to 1.3 times, the second distance d2.

[0060] The structure of the side flaps 60 can be determined as appropriate, and structures similar to those described in Patent Documents 1 to 3 can be employed. However, the illustrated example is preferred because it is simple, waterproof, and easy to manufacture. Specifically, the side flaps 60 in the illustrated example include a top nonwoven fabric layer 61 that forms the top surface of the side flap 60, a back nonwoven fabric layer 62 that forms the back surface of the side flap 60, elongated gathered elastic members 631-633 that are provided between the top nonwoven fabric layer 61 and the back nonwoven fabric layer 62 along the front-to-rear direction, and a liquid-impermeable film 64 (11) that is sandwiched between the top nonwoven fabric layer 61 and the back nonwoven fabric layer 62 and extends from the base end to a position closer to the tip than the base end. In the illustrated example, a nonwoven fabric-free portion 65 is formed in a portion of the width of the side flap where the top nonwoven fabric layer 61 is absent and the liquid-impermeable film 64 is exposed. However, the top nonwoven fabric layer 61 may be configured to extend across substantially the entire width of the side flap. When nonwoven fabric-free portion 65 is provided, its width can be determined appropriately, but it is preferable that it is 10 mm or less.

[0061] In particular, if there is a portion 65 (including a gap in the surface nonwoven fabric layer 61 with almost no width) between the first gathered elastic member 631 and the second gathered elastic member 632 where the surface nonwoven fabric layer 61 is not present and the liquid-impermeable film 64 is exposed, this portion will have low rigidity, and the portion between the first gathered elastic member 631 and the second gathered elastic member 632 will be particularly prone to deformation, which is preferable.

[0062] The portion between the first gathered elastic member 631 and the second gathered elastic member 632 preferably has low rigidity because it is a portion that exerts a cushioning effect. As shown in the illustrated example, when the portion between the first gathered elastic member 631 and the second gathered elastic member 632 has a three-layer structure of a front nonwoven fabric layer 61, a back nonwoven fabric layer 62, and a liquid-impermeable film sandwiched between them, and the front nonwoven fabric layer 61 and the liquid-impermeable film 11 are bonded together via a first hot-melt adhesive HM1 and the back nonwoven fabric layer 62 and the liquid-impermeable film 11 via a second hot-melt adhesive HM2, the bending resistance of each of the front nonwoven fabric layer 61 and the back nonwoven fabric layer 62, as measured by the 41.5° cantilever method defined in JIS L 1913:2010, is preferably 0.2 to 2.2 mN·cm in the front-to-back direction LD and 0.05 to 0.5 mN·cm in the width direction WD, and particularly preferably 0.4 to 0.6 mN·cm in the front-to-back direction LD and 0.07 to 0.1 mN·cm in the width direction WD. The liquid-impermeable film preferably has a bending resistance of 0.006 to 0.05 mN·cm in the longitudinal direction (LD) and 0.006 to 0.05 mN·cm in the width direction (WD) as measured by the 41.5° cantilever method specified in JIS L 1913:2010, and particularly preferably has a bending resistance of 0.006 to 0.02 mN·cm in the longitudinal direction (LD) and 0.006 to 0.02 mN·cm in the width direction (WD). The amount of application of the first hot melt adhesive (HM1) is 1 to 10 g / m. 2 , especially 1 to 5 g / m 2 The amount of the second hot melt adhesive HM2 to be applied is preferably 1 to 10 g / m 2 , especially 1 to 5 g / m 2 It is preferable that:

[0063] 9, when the back body B is placed face down on a horizontal surface and only the outer casing 12 is unfolded along the flat surface from its natural length and viewed from above, the acute-side crossing angle α between the front-to-back direction LD and an imaginary line connecting the side edges of the absorber 56 and the first gathered elastic member 631 among the outlines of the crotch region M is 15 to 40 degrees, the acute-side crossing angle γ between the front-to-back direction LD and an imaginary line connecting the positions of adjacent third gathered elastic members 633 is 50 to 90 degrees, and the acute-side crossing angle β between the front-to-back direction LD and an imaginary line connecting the positions of the first gathered elastic member 631 and the second gathered elastic member 632 is preferably greater than α but less than γ, since this improves the cushioning effect described above. The angle α is more preferably 25 to 35 degrees. The angle γ is more preferably 55 to 70 degrees. The angle β is more preferably approximately 1.3 to 1.7 times the value of α.

[0064] The front-to-rear direction LD range in which the gathered elastic members 631 to 633 are provided in the side flaps 60 can be determined as appropriate as long as it extends from the side of the widest part 54 of the absorber 56 in front of the crotch region M to the side of the widest part 54 of the absorber 56 behind the crotch region M, but it is desirable that it extends from the stretchable region of the waist region T of the front body F to the stretchable region of the waist region T of the back body B.

[0065] As long as the gathered elastic members 631 to 633 are provided between the surface nonwoven fabric layer 61 and the back nonwoven fabric layer 62 (and therefore are not provided in the nonwoven fabric-free portion 65), they can be provided on the front side of the liquid-impermeable film 64 built into the side flap 60 as shown in Figure 3, or on the back side (not shown).

[0066] The position of the liquid-impermeable film 64 on the side flap 60 can be determined as appropriate, and if waterproofing is a priority, it is preferable for it to extend across the entire width of the side flap. However, in order to ensure flexibility of the side edges of the side flap, it is also preferable not to have the liquid-impermeable film 64 on the side edge portion (for example, from between the most lateral third gathered elastic member and the second adjacent third gathered elastic member to the side edge of the side flap).

[0067] The surface nonwoven fabric layer 61 and the back nonwoven fabric layer 62 may be made of a nonwoven fabric different from the top sheet 30 and the cover nonwoven fabric layer 13, but are also preferably made of the same nonwoven fabric as the top sheet 30 and the cover nonwoven fabric layer 13. That is, in the illustrated example, the top sheet 30 is made of a nonwoven fabric and is configured so that both sides in the width direction WD extend beyond the side edges of the absorbent body 56, and a nonwoven fabric 66 that constitutes the cover nonwoven fabric layer 13 is provided on the back side of the absorbent body 56 and both sides in the width direction WD extend laterally from the side edges of the absorbent body 56, and further, the side edges of this nonwoven fabric 66 are folded back, with the tips of the folded back portions 66r spaced apart from the tip of the top sheet 30. In addition, a liquid-impermeable film 64 is provided at least from between the folded back portions 66r of the nonwoven fabric 66 to between the top sheet 30 and the nonwoven fabric 66. As a result, the back surface nonwoven fabric layer 62 is formed by the parts of the nonwoven fabric 66 other than the folded-back parts 66r, the front surface nonwoven fabric layer 61 is formed by the folded-back parts 66r of the nonwoven fabric 66 and the parts of the top sheet 30 that extend to the sides of the absorbent body 56, and the nonwoven fabric-free parts 65 are formed by the parts where the folded-back parts 66r of the nonwoven fabric 66 are separated from the top sheet 30. In this way, by forming the front surface nonwoven fabric layer 61 on the absorbent body 56 side of the nonwoven fabric-free parts 65 of the side flaps 60 from the top sheet 30 and forming the rest from the folded-back parts 66r of the nonwoven fabric 66, the nonwoven fabric-free parts 65 can be provided without cutting the material, and the structure is very simple and easy to manufacture.

[0068] In this case, it is preferable that the liquid-impermeable film 64 built into the side flaps 60 extend from one side flap 60 through the back side of the absorber 56 to the other side flap 60, as shown in Figures 3 and 4, because this not only ensures water-tightness of the side flaps 60 but also the back side of the absorber 56, but it is also possible to provide the liquid-impermeable film 64 built into the side flaps 60 and the liquid-impermeable film 64 covering the back side of the absorber 56 separately. In the latter case, the material of the liquid-impermeable film 64 built into the side flaps 60 and the material of the liquid-impermeable film 11 covering the back side of the absorber 56 may be the same or different (for example, less rigid).

[0069] At least one of various application methods of hot melt adhesive and material welding fixing means such as heat sealing and ultrasonic sealing can be used to bond the front nonwoven fabric layer 61 and the back nonwoven fabric layer 62 together and to fix the gathered elastic members 631-633 sandwiched between them. Since bonding the entire surfaces of the front nonwoven fabric layer 61 and the back nonwoven fabric layer 62 together reduces flexibility, it is preferable that the areas other than the bonded portions of the gathered elastic members 631-633 are not bonded or are only weakly bonded. In the illustrated example, hot melt adhesive is applied only to the outer peripheral surfaces of the gathered elastic members 631-633 using an application means such as a comb gun or a SureWrap nozzle, and then these are sandwiched between the front nonwoven fabric layer 61 and the back nonwoven fabric layer 62, so that the hot melt adhesive applied only to the outer peripheral surfaces of the gathered elastic members 631-633 secures the elongated elastic members to the front nonwoven fabric layer 61 and the back nonwoven fabric layer 62, and secures the front nonwoven fabric layer 61 and the back nonwoven fabric layer 62 together. If there are edges of a nonwoven fabric or sheet separated from the gathered elastic members 631-633, such as the edges 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 these edges.

[0070] In the front and rear end portions of the side flaps 60, in the portions not having the gathered elastic members 631-633, it is desirable to fix the member adjacent to the front side of the gathered elastic members 631-633 (the surface nonwoven fabric layer 61 in the illustrated example) and the member adjacent to the back side of the gathered elastic members 631-633 (the liquid-impermeable film 64 in the illustrated example) by at least one of a hot melt adhesive and material welding (heat sealing, ultrasonic sealing, etc.). In the drawing, this fixing portion is indicated by the reference numeral 67.

[0071] The surface nonwoven fabric layer 61 and the back nonwoven fabric layer 62 can be suitably made of a nonwoven fabric that is soft and has excellent uniformity and hiding power, such as a spunbond nonwoven fabric (SS, SSS, etc.), an SMS nonwoven fabric (SMS, SSMMS, etc.), or a meltblown nonwoven fabric, and is subjected to a water-repellent treatment with silicone or the like 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 61 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 61 and the back nonwoven fabric layer 62 partially different, and it is also possible to make the materials of the surface nonwoven fabric layer 61 and the back nonwoven fabric layer 62 different.

[0072] <Explanation of terms used in the specification> In the present specification, the following terms have the following meanings unless otherwise specified in the specification.

[0073] "Front-rear direction" refers to the direction indicated by the symbol LD in the drawing (longitudinal direction), and "width direction" refers to the direction indicated by the symbol WD in the drawing (left-right direction), with the front-rear direction and width direction being perpendicular to each other.

[0074] "Front side" means the side closest to the wearer's skin when worn, and "reverse side" means the side farthest from the wearer's skin when worn.

[0075] "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.

[0076] "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.

[0077] "Gel strength" is measured as follows: 1.0 g of superabsorbent polymer is added to 49.0 g of artificial urine (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 stirred with a stirrer. The resulting gel is left in a constant temperature and humidity chamber at 40°C and 60% RH for 3 hours, then returned to room temperature, and the gel strength is measured using a card meter (I.techno Engineering: Curdmeter-MAX ME-500).

[0078] "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, use a sample collection template (100mm x 100mm) to cut out a sample measuring 100mm x 100mm. Measure the weight of the sample and multiply it by 100 to calculate the weight per square meter, which is the basis weight.

[0079] The "thickness" of thick members such as the absorber 56, the absorbent element 50, and the bottom of the compression section 51 is measured using a thickness measuring device (Peacock, Dial Thickness Gauge, Model H (measurement range 0 to 10 mm, measurement area 10 mm diameter circular terminal, measurement force approximately 1.7 N, pressure approximately 21.7 KPa)) manufactured by Ozaki Manufacturing Co., Ltd., with the sample and thickness measuring device positioned horizontally.

[0080] 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 Automatic measurement is performed under the following conditions.

[0081] The water absorption capacity is measured according to JIS K7223-1996 "Test method for water absorption capacity of superabsorbent resins."

[0082] The water absorption rate is the "time to the end point" when 2g of superabsorbent polymer and 50g of physiological saline are used and tested according to JIS K7224-1996 "Test method for water absorption rate of superabsorbent polymers."

[0083] "Deployed state" means a flat, deployed state without contraction (including any contraction, such as contraction due to elastic members) or slack.

[0084] Unless otherwise specified, the dimensions of each part refer to the dimensions in the unfolded state, not in the natural length state.

[0085] If no environmental conditions are specified for a test or measurement, 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%). [Industrial Applicability]

[0086] The present invention can be used in pants-type disposable wearing articles such as the pants-type disposable diaper described above. [Explanation of symbols]

[0087] 11...liquid-impermeable film, 12...exterior body, 12A...side seal portion, 12B...rear exterior body, 12F...front exterior body, 12H...inner sheet layer, 12S...outer sheet layer, 13...cover nonwoven fabric layer, 14...buttocks cover portion, 15...waist lower elastic member, 16...buttocks cover elastic member, 17...waist elastic member, 200...interior body, 201...interior body joint portion, 30...top sheet, 50...absorbent element, 51...compression portion, 52...minimum width portion, 53...widened portion, 54...maximum width portion, 56...absorbent body, 56C...central region, 56S...side region, 58...packaging sheet, 60...side flap, 60A...first portion, 60B...second portion, 61...surface nonwoven fabric layer, 62...back nonwoven fabric layer, 631-633...gathered elastic member, 631...first gathered elastic member, 632...second gathered elastic member, 633...third gathered elastic member, 64...liquid-impermeable film, 65...nonwoven fabric absent portion, 66...gathered sheet, 66r...folded-up portion, B...back body, F...front body, HM1...first hot melt adhesive, HM2...second hot melt adhesive, L...middle region, LD...front and rear direction, M...crotch region, T...torso region, U...lower waist portion, W...waist portion, WD...width direction, WO side...waist opening WO, d1...first spacing, d2...second spacing, d3...third spacing.

Claims

1. An integrated outer body extending from the front body to the back body, or an outer body provided separately on the front body and the back body, An inner body attached to the middle of the outer body in the width direction from a position forward of the crotch area to a position rearward of the crotch area; A pair of side seals formed by joining both side portions of the exterior body in the front body and both side portions of the exterior body in the back body, respectively; a waist opening formed by the front edge of the front body and the rear edge of the back body; leg openings provided on both sides of the interior body, the inner body has an absorbent body that continues from a position in front of the crotch region to a position in back of the crotch region, The absorber has maximum width portions on the front side of the crotch region and on the rear side of the crotch region, A pair of side flaps extend from the side edges of the absorbent body to both sides in the width direction on both sides of the inner body, and extend in the front-rear direction from the front end to the rear end of the inner body, the side flaps have planar gathers that extend from the sides of the maximum width portion of the absorber on the front side of the crotch region to the sides of the maximum width portion of the absorber on the rear side of the crotch region, The plane gathers are portions incorporating elongated gathered elastic members along the front-to-rear direction, and are contracted in the front-to-rear direction together with the gathered elastic members, and are also extensible in the front-to-rear direction together with the gathered elastic members, Does not have three-dimensional gathers that rise up on the front side A pants-type disposable wearing article; The width of the side flaps is 0.1 to 0.5 times the maximum width of the absorbent body, The gathered elastic members comprise a first gathered elastic member attached laterally at a first interval from the side edge of the widest portion of the absorbent body, a second gathered elastic member attached laterally at a second interval from the first gathered elastic member, and a third gathered elastic member attached repeatedly to the side edge of the side flap at a third interval from the second gathered elastic member, the first gathered elastic member has a first thickness and is attached to the side flap with a first elongation rate; the second gathered elastic member has a second thickness and is attached to the side flap with a second elongation rate; the third gathered elastic member has a third thickness and is attached to the side flap with a third elongation rate; the second spacing is 1.5 to 5 times the third spacing; the first spacing is 0.3 to 0.8 times the second spacing; the first elongation rate is 0.95 to 1.05 times the second elongation rate and the third elongation rate, and the first thickness is 1.2 to 1.5 times the second thickness and the third thickness, or the first thickness is 0.95 to 1.05 times the second thickness and the third thickness, and the first elongation rate is 1.2 to 1.5 times the second elongation rate and the third elongation rate, or the first thickness is 1.2 to 1.5 times the second thickness and the third thickness, and the first elongation rate is 1.2 to 1.5 times the second elongation rate and the third elongation rate, the absorber has a minimum width portion in the crotch area, and has widening portions whose widths gradually increase from the minimum width portion to a maximum width portion on the front side and to a maximum width portion on the rear side, When the back body is placed on a horizontal surface with the back portion facing downwards, and only the outer body is unfolded along the flat surface from its natural length, and viewed from above, Among the outline lines of the crotch region, an acute-angle side crossing angle α formed by an imaginary line connecting the positions of the side edges of the absorber and the positions of the first gathered elastic members and the front-to-back direction is 15 to 40 degrees, an acute-angle side crossing angle γ formed by an imaginary line connecting the positions of adjacent third gathered elastic members and the front-to-back direction is 50 to 90 degrees, and an acute-angle side crossing angle β formed by an imaginary line connecting the positions of the first gathered elastic members and the positions of the second gathered elastic members and the front-to-back direction satisfies the relationship α<β<γ. A pants-type disposable wearing article characterized by:

2. the absorber has a minimum width portion in the crotch area, and has widening portions whose widths gradually increase from the minimum width portion to a maximum width portion on the front side and to a maximum width portion on the rear side, the widthwise distance between the side edge of the minimum width portion of the absorbent body and the first gathered elastic member is 1.1 to 1.5 times the second distance; 2. The pants-type disposable wearing article according to claim 1.

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