JP6386883B2 - Absorbent articles - Google Patents

Description

  The present invention relates to an absorbent article such as a disposable diaper.

  As an absorbent article such as a disposable diaper, a liquid-retaining absorbent core is provided, and an abdominal side portion disposed on the abdomen side of the wearer, a back side portion disposed on the back side, and a crotch portion positioned therebetween In addition, an absorbent article having a longitudinal direction extending from the abdominal side portion to the back side portion via the crotch portion and a lateral direction perpendicular thereto is known. In addition, as an absorbent body of an absorbent article, an absorbent core made of a fiber assembly made of a fiber material such as defibrated pulp or a functional material such as a water-absorbing polymer, etc. Those coated with a core wrap sheet made of the same are widely used. In order to improve the deformability of the absorbent body and improve the fit and leakage prevention properties, various techniques for providing an opening in the absorbent core without the absorbent core forming material have been proposed. For example, Patent Document 1 discloses that in a disposable diaper having an absorbent core having a single-layer structure, a central opening extending in the vertical direction is formed at the lateral central portion of the absorbent core, and the lateral side of the central opening is formed. It is described that a lateral opening extending in the vertical direction is formed on both outer sides in the direction. According to Patent Literature 1, when the disposable diaper is worn by the plurality of openings formed in the absorbent core, the absorbent core is deformed into a W shape in a cross-sectional view along the lateral direction, and fit property It is supposed to improve.

  Patent Documents 2 and 3 describe forming a plurality of openings in the absorbent core in a disposable diaper having a two-layer absorbent core composed of an upper layer and a lower layer. In the disposable diaper described in Patent Document 2, a central opening portion in which the two-layer structure portion (high basis weight portion) of the absorbent core is arranged in the lateral center portion of the diaper and penetrates the entire two-layer structure portion in the thickness direction. (Center bending guide part) is formed so as to extend in the vertical direction, and the single-layer structure part (low basis weight part) consisting only of the lower layer on both lateral sides of the central opening is laterally An opening (side bending guide) is formed to extend in the vertical direction. On the other hand, in the disposable diaper described in Patent Document 3, as in the disposable diaper described in Patent Document 2, a central opening and a lateral opening are formed in the absorbent core. Whereas the portion is formed not only in the lower layer but also in the upper layer, in Patent Document 3, the central opening is formed only in the lower layer and not in the upper layer. Moreover, in the disposable diaper described in Patent Document 3, the central opening has a shorter length in the vertical direction than the upper layer, and the central opening does not extend over the entire length of the upper layer in the vertical direction.

JP 2011-177310 A JP 2012-16435 A JP2013-13524A

  Since the disposable diaper described in Patent Documents 1 to 3 is configured to be bent at a plurality of openings formed in the absorbent core, it is compressed inward in the lateral direction by the wearer's thighs during wearing. If it is done, the whole diaper will deform | transform and, thereby, a high feeling of wear and leak prevention may be expressed. However, the disposable diapers described in Patent Documents 1 to 3 have room for improvement in terms of ease of deformation of the absorbent core and maintenance of the shape after deformation.

  Therefore, this invention relates to the absorbent article which is excellent in a feeling of wear and leak-proof property.

The present invention comprises a liquid-retaining absorbent core, has an abdominal side portion arranged on the abdomen side of the wearer, a back side portion arranged on the back side, and a crotch portion positioned therebetween, An absorbent article having a longitudinal direction extending from the abdominal side portion to the back side portion through the crotch portion and a lateral direction perpendicular thereto,
The absorbent core is configured to include a two-layer structure including an upper absorbent core and a lower absorbent core disposed on the non-skin facing surface side of the upper absorbent core,
A narrow central opening that penetrates the lower absorbent core in the thickness direction is formed at the lateral center of the lower absorbent core so as to extend in the vertical direction. On both outer sides, a pair of narrow lateral openings that penetrate the lower layer absorbent core in the thickness direction extend in the vertical direction and are formed symmetrically with respect to the central opening,
The upper absorbent core and the central opening overlap in plan view, and the central opening extends over the entire length in the longitudinal direction of the upper absorbent core,
The upper absorbent core is not formed with an opening extending in the longitudinal direction through the upper absorbent core in the thickness direction in a region overlapping the central opening of the lower absorbent core in plan view,
A pair of three-dimensional gathers that stand up toward the wearer's skin when worn are provided on the skin facing surface sides of the left and right side portions along the longitudinal direction of the absorbent core. The skin-facing surface side has a base end portion and stands up so as to form a free end on the skin side of the wearer.
The present invention provides an absorbent article in which the elastic member for forming a three-dimensional gather and the absorbent core overlap each other in a plan view of the absorbent article in a developed and extended state.

  ADVANTAGE OF THE INVENTION According to this invention, the absorbent article which is excellent in a feeling of wear and leak prevention property is provided.

FIG. 1 is a perspective view schematically showing a pants-type disposable diaper that is an embodiment of the absorbent article of the present invention. FIG. 2 is a developed plan view schematically showing the skin facing surface side (inner surface side) in the developed and extended state of the diaper shown in FIG. FIG. 3 is a developed plan view schematically showing the non-skin facing surface side (outer surface side) in the developed and extended state of the diaper shown in FIG. 1. FIG. 4 is a cross-sectional view schematically showing a cross section taken along line II of FIG. FIG. 5 is an exploded perspective view schematically showing the diaper shown in FIG. 1 in an exploded manner. FIG. 6 is a partially broken perspective view schematically showing an example of a part of the stretchable outer layer sheet (abdominal side outer layer sheet) constituting the outer package of the diaper shown in FIG. 1. FIG. 7 is an enlarged plan view schematically showing an enlarged skin facing surface side of the absorbent core of the diaper shown in FIG. 1. FIG. 8 is a cross-sectional view schematically showing the state of the absorbent main body when the diaper shown in FIG. 1 is worn. Fig.9 (a) and FIG.9 (b) are each a top view which shows typically the skin opposing surface side of the absorptive core used by the comparative example.

  The present invention will be described below based on preferred embodiments with reference to the drawings. The pants type disposable diaper 1 which is one Embodiment of the absorbent article of this invention is described by FIGS. The diaper 1 includes a liquid-retaining absorbent core 23 that absorbs and retains bodily fluids such as excreted urine, and includes a ventral side 1A disposed on the wearer's ventral side and a dorsal side 1C disposed on the dorsal side. And a crotch part 1B located between them and disposed in the wearer's crotch part, and a longitudinal direction X and a transverse direction Y orthogonal thereto. The longitudinal direction X of the diaper 1 is a direction that extends between the abdomen 1A and the back 1C via the crotch 1B.

  More specifically, the diaper 1 includes an absorbent main body 2 having an absorbent core 23, and an exterior body 3 that is disposed on the non-skin-facing surface side of the absorbent main body 2 and fixes the absorbent main body 2. The side edges FS and RS along the longitudinal direction X of the outer body 3 in the front body F and the back body R are joined to each other so that the pair of side seal portions S and S and the wearer's torso are passed A waist opening WH and a pair of leg openings LH and LH through which a wearer's lower limb is passed are formed.

  As shown in FIGS. 2 and 3, the front body F is worn on the wearer's body on the basis of a vertical center line (not shown) extending in the horizontal direction Y so as to bisect the diaper 1 in the vertical direction X. The back body R is a portion that covers the front side (abdominal side), and the back body R is a portion that covers the back side (back side) of the wearer's body. Moreover, in this specification, a skin opposing surface is a surface (side near a wearer's skin) which is turned to a wearer's skin side in the wearing state in the diaper 1 and its structural member (for example, absorptive main body 2), The non-skin facing surface is a surface (a side farther from the skin than the skin facing surface) directed toward the side opposite to the wearer's skin side in the wearing state in the diaper 1 and its constituent members.

  The diaper 1 includes an abdominal side portion 1A disposed on the abdomen side of the wearer in a worn state, a back side portion 1C disposed on the back side, and a crotch portion positioned between them and disposed on the crotch portion of the wearer. 1B. The longitudinal direction X of the diaper 1 is a direction extending between the front body F and the back body R, that is, a direction extending between the abdominal side 1A and the back side 1C via the crotch 1B, and absorbs It coincides with the longitudinal direction of the main body 2. The abdominal side 1A is a part of the front body F, the back side 1C is a part of the back body R, and the crotch 1B extends over the front body F and the back body R. The abdominal side portion 1A and the back side portion 1C are portions that are in the same position as the side seal portion S in the longitudinal direction X, and are waist portions that are arranged around the wearer's waist when the diaper 1 is worn. The crotch part 1 </ b> B is a region in which concave openings (leg edges LS, LS) for forming leg openings LH, LH are formed at both side edges along the longitudinal direction X of the exterior body 3. The crotch part 1 </ b> B has an excretion part facing part that is disposed so as to face the wearer's excretion part when the diaper 1 is worn, and the excretion part facing part is usually a central part in the longitudinal direction X of the diaper 1 (diaper 1 On the vertical center line) or in the vicinity thereof.

  The absorbent main body 2 has a rectangular shape in plan view as shown by the outlines in FIGS. 2 and 3, and its longitudinal direction is made to coincide with the vertical direction X of the diaper 1 in the expanded and extended state. It arrange | positions in the center part of the horizontal direction Y of the body 3, and is joined to the exterior body 3 with the adhesive agent. The outer package 3 forms the outer shape of the diaper 1 in the unfolded and extended state of the diaper 1 as shown in FIGS. 2 and 3, and the periphery of the outer package 3 forms the outline of the diaper 1 in that state. . The “expanded and extended state” of the diaper 1 means that the diaper 1 is separated by the side seal portion S to be in the expanded state, and the expanded diaper 1 is stretched by the elastic member of each part to design dimensions (the influence of the elastic member is not at all). It means a state in which it is expanded until it becomes the same size as when it is expanded in a flat state in the excluded state.

  As shown in FIG. 4, the absorbent main body 2 includes a liquid-permeable surface sheet 21 that forms a skin-facing surface, and a liquid-impermeable or liquid-permeable or water-repellent back sheet 22 that forms a non-skin-facing surface. , And a liquid-retaining absorbent core 23 (an upper absorbent core 230 and a lower absorbent core 231) interposed between both sheets 21 and 22, which are known joining means such as an adhesive. It is integrated and configured. The absorptive core 23 is located in the center part of the horizontal direction Y of the diaper 1 (exterior body 3). The surface of the absorbent core 23 is covered with a core wrap sheet 232. The core wrap sheet 232 is made of a liquid permeable sheet such as paper such as tissue paper, various nonwoven fabrics, and an apertured film, and integrally covers the upper absorbent core 230 and the lower absorbent core 231. As the top sheet 21, the back sheet 22, and the absorbent core 23, various types conventionally used for this type of absorbent article can be used without particular limitation. For example, various nonwoven fabrics or apertured films can be used as the top sheet 21, and a resin film, a laminate of a resin film and a nonwoven fabric, or the like can be used as the back sheet 22. As a forming material of the absorptive core 23 (upper layer absorptive core 230 and lower layer absorptive core 231), 1 or more types of fiber materials, such as a water absorbing polymer particle and a pulp fiber, can be used, for example.

  As shown in FIGS. 2 and 4, a pair of three-dimensional gathers 24, 24 that stand up toward the wearer's skin when worn on the skin facing surface sides of the left and right side portions along the longitudinal direction X of the absorbent core 23. Is provided. Each three-dimensional gather 24 has a base end portion 27 on the skin-facing surface side of the absorbent core 23 and rises to form a free end 28 on the skin side of the wearer, and one or a plurality ( In the present embodiment, a plurality of elastic members 26 for forming a three-dimensional gather are arranged in an elongated state in the vertical direction X. In the present embodiment, the pair of three-dimensional gathers 24, 24 extend linearly over the entire length in the longitudinal direction X of the absorbent main body 2, and when the diaper 1 is worn, at least in the crotch 1B, Stand up toward the skin. The base end portion 27 of the three-dimensional gather 24 extends linearly over the entire length in the longitudinal direction X of the absorbent main body 2 in a plan view as shown in FIG. 2, and is located on the skin facing surface of the absorbent core 23. ing. 4 shows a cross section of the constricted portion (the central portion in the longitudinal direction X) of the absorbent core 23. In FIG. 4, the base end portion 27 of the three-dimensional gather 24 is a space near the constricted portion. The front and rear ends in the longitudinal direction X of the absorbent core 23 which is located on the part and is not located on the portion where the absorbent core forming material exists (the lower layer absorbent core 231) but does not have the constricted part In the part, the base end part 27 is located on the lower layer absorbent core 231, and the base end part 27 as a whole is located on the skin facing surface of the absorbent core 23.

  In the plan view of the diaper 1 as shown in FIG. 2 in the unfolded and extended state, the three-dimensional gather forming elastic member 26 and the absorbent core 23 overlap each other. That is, the elastic member 26 (at least one elastic member 26 when there are a plurality of elastic members 26) vertically cuts at least a part of the skin facing surface of the absorbent core 23 in the vertical direction.

  As shown in FIG. 4, the three-dimensional gather 24 includes a liquid-resistant or water-repellent three-dimensional gather forming sheet material 25 and a three-dimensional gather forming elastic member 26 fixed to the sheet material 25. . The sheet material 25 is formed from a single belt-like sheet, and one end portion in the lateral direction Y of the sheet material 25 is disposed between the absorbent core 23 (core wrap sheet 232) and the back sheet 22 and is an adhesive. The other end portion in the lateral direction Y of the sheet material 25 is bent above the surface sheet 21 covering the skin facing surface of the absorbent core 23 and extends in the longitudinal direction X (see FIG. (Not shown) is folded back inward in the lateral direction Y to form a free end 28, and the elastic member 26 in the form of a thread or belt extends in the longitudinal direction X between the sheets facing each other by the folding. The three-dimensional gather 24 is formed by being fixed through the agent. The three-dimensional gather 24 stands up when the elastic member 26 arranged in the stretched state contracts when the diaper 1 is worn, and prevents the liquid from flowing out to the side. As the sheet material 25 for forming a three-dimensional gather, a stretchable film, a nonwoven fabric, a woven fabric, or a laminated sheet thereof can be used.

  As shown in FIGS. 2 and 3, the exterior body 3 has a pair of leg edges LS and LS whose both side edges along the longitudinal direction X are curved inwardly in an arc shape in the crotch 1B. 2 and FIG. 3, in the plan view, the central region in the vertical direction X has an hourglass shape that is bound inward in the horizontal direction Y. In the crotch 1B, there is a portion of the exterior body 3 that has the shortest length in the lateral direction Y. The exterior body 3 has both side edges FS, FS along the longitudinal direction X in the front body F (abdominal side 1A) and both side edges RS, RS along the longitudinal direction X in the back body R (back side 1C). Are joined together by a known joining means such as an adhesive, heat seal, ultrasonic seal, etc., and as a result of the joining, as shown in FIG. 1, a pair of side seal portions S, S is formed on the diaper 1. A waist opening WH and a pair of leg openings LH, LH are formed.

  As shown in FIGS. 4 and 5, the exterior body 3 is configured to include a laminated body of an outer layer sheet 31 and an inner layer sheet 32. In the wearing state of the diaper 1, the outer layer sheet 31 is located on the side far from the wearer's body to form a non-skin facing surface (outer surface) of the diaper 1, and the inner layer sheet 32 is on the side closer to the wearer's body. Position to form the skin facing surface (inner surface) of the diaper 1. The outer layer sheet 31 and the inner layer sheet 32 are joined by an adhesive at a predetermined site.

  In the present embodiment, as shown in FIG. 5, the inner layer sheet 32 is composed of a single continuous sheet, whereas the outer layer sheet 31 is composed of a combination of a plurality of sheets. It includes a ventral outer layer sheet 31A constituting the side portion 1A, a dorsal outer layer sheet 31C constituting the back side portion 1C, and a crotch outer layer sheet 31B constituting the crotch portion 1B located between the sheets 31A and 31C. It consists of Each of the sheets 31A, 31B, 31C constituting the outer layer sheet 31 is overlapped with each other in the longitudinal direction X, and a known joining such as an adhesive, a heat seal, a high frequency seal, an ultrasonic seal, etc. They are joined and integrated by means. In the overlapping portion of the sheets 31A and 31C and the sheet 31B, the sheet 31B located in the center of the longitudinal direction X is located on the side relatively close to the absorbent main body 2, and both ends of the sheet 31B in the longitudinal direction X The non-skin facing surface of the part is covered with sheets 31A and 31C.

  As shown in FIGS. 2 and 5, the ventral outer layer sheet 31 </ b> A has a ventral extension part 31 </ b> AE that extends outward from the end in the longitudinal direction X on the ventral part 1 </ b> A side of the inner layer sheet 32. The back side outer layer sheet 31C has a back side extending part 31CE extending outward from the end in the longitudinal direction X on the back side part 1C side of the inner layer sheet 32, and both extending parts 31AE, 31AE, 31CE is folded back to the inner layer sheet 32 side so as to cover both ends in the longitudinal direction X of the absorbent main body 2 arranged and fixed on the inner layer sheet 32, and both extended portions 31AE, 31CE and It is being fixed to the other structural member (Inner layer sheet 32, the absorptive main body 2, the three-dimensional gathers 24) which opposes the diaper 1 which opposes.

  In the present embodiment, the abdominal side outer layer sheet 31A and the back side outer layer sheet 31C constituting the outer layer sheet 31 have elasticity in the lateral direction Y, whereas the remaining part of the outer layer sheet 31 (inseam outer layer sheet) 31B) and the inner layer sheet 32 are not stretchable and non-stretchable. Therefore, in the exterior body 3, the region including the sheets 31A and 31C has stretchability in the lateral direction Y, and the region not including the sheets 31A and 31C does not have stretchability in the lateral direction Y. In the present embodiment, the abdominal side portion 1A that is the waist portion of the front body F includes the abdominal outer layer sheet 31A, and the back side portion 1C that is the waist portion of the back body R includes the back side outer layer sheet 31C. Both the side portion 1A and the back side portion 1C have elasticity in the lateral direction Y. Further, in the present embodiment, the ventral outer layer sheet 31A is a boundary between the ventral portion 1A and the crotch 1B, that is, the lower ends of the pair of side seal portions S, S in the front body F (inward in the longitudinal direction X). The rear outer layer sheet 3C extends beyond the imaginary straight line extending in the lateral direction Y through the end of the side), and the back outer layer sheet 3C is at the boundary between the back side 1C and the crotch 1B, that is, at the back body R. Since it extends to the crotch part 1B through the lower end (the end part on the inner side in the vertical direction X) of each of the pair of side seal parts S and beyond the virtual straight line extending in the horizontal direction Y, the crotch part 1B The portions including the extending portions of both the seats 31A and 31C, that is, the portions near the abdominal side portion 1A and the back side portion 1C in the crotch portion 1B also have elasticity in the lateral direction Y, respectively. On the other hand, the portions other than those near the ventral side 1A and the back side 1C in the crotch part 1B (the central part in the vertical direction X of the crotch part 1B) do not have elasticity in the horizontal direction Y.

  The ventral outer layer sheet 31 </ b> A and the back outer layer sheet 31 </ b> C have elasticity in at least the lateral direction Y. FIG. 6 shows an example of a stretchable ventral outer layer sheet 31A. The ventral outer layer sheet 31A shown in FIG. 6 has a configuration in which a thread-like elastic filament is bonded to one surface of an extensible fiber layer mainly composed of inelastic fibers, and two fiber sheets 41 as the fiber layers. , 42 and an elastic member 43 as an elastic filament disposed between both sheets 41, 42. The stretchable backside outer layer sheet 31A having such a configuration can be manufactured, for example, according to the method described in JP-A-2009-61743. The stretchable backside outer layer sheet 31C can also be configured in the same manner as the stretchable ventral side outer layer sheet 31A shown in FIG.

  The two sheets 41 and 42 constituting the ventral outer layer sheet 31A are both extensible. The sheets 41 and 42 can extend in the same direction as the direction in which the elastic member 43 extends (lateral direction Y). Stretchable means (a) when the constituent fibers themselves of the sheets 41 and 42 are stretched, and (b) even if the constituent fibers themselves do not stretch, This includes a case in which the three-dimensional structure formed by a plurality of fibers is structurally changed due to bonding or the like, or the constituent fibers are broken, and the sheets 41 and 42 are stretched as a whole.

  The elastic member 43 constituting the ventral outer layer sheet 31A is an elastic filament formed by being stretched in a state where the elastic resin is melted or softened. The plurality of elastic members 43 are substantially continuous over the entire length of the sheet 31 </ b> A (the total length in the lateral direction Y of the exterior body 3). The plurality of elastic members 43 are arranged so as to extend in one direction (lateral direction X) without crossing each other. The elastic member 43 is joined to the two sheets 41 and 42 in a substantially non-extended state. In the sheet 31 </ b> A, the elastic member 43 is joined to the sheets 41 and 42 by fusing the elastic members 43 with the fibers (non-elastic fibers) constituting the sheets 41 and 42 embedded in the elastic members 43. However, it is not made using an adhesive such as a hot-melt adhesive. Therefore, there is no adhesive between the sheets 41 and 42 (extensible fiber layer mainly composed of non-elastic fibers) and the elastic member 43 bonded thereto.

  The ventral outer layer sheet 31A can be expanded and contracted in the same direction as the direction in which the elastic member 43 extends (lateral direction Y). The stretchability of the sheet 31 </ b> A appears due to the elasticity of the elastic member 43. When the sheet 31A is stretched in the same direction as the direction in which the elastic member 43 extends, the elastic member 43 and the sheets 41 and 42 expand. When the stretching of the sheet 31A is released, the elastic member 43 contracts, and the sheets 41 and 42 return to the state before the stretching with the contraction. Further, in the sheet 31A, there is no other elastic member coupled in a state orthogonal to the elastic member 43, and therefore the sheet 31A is stretched in the same direction as the direction in which the elastic member 43 extends (lateral direction Y). When this occurs, the sheet 31 </ b> A contracts in the transverse direction Y, and expands with little so-called width contraction.

  Each of the two sheets 41 and 42 constituting the ventral outer layer sheet 31A may be a short fiber nonwoven fabric. Examples of the nonwoven fabric include air-through nonwoven fabric, heat roll nonwoven fabric, spunlace nonwoven fabric, spunbond nonwoven fabric, and meltblown nonwoven fabric. The sheet 41 and the sheet 42 may be the same type or different types. As used herein, the “same type of sheet” means sheets having the same manufacturing process, types of constituent fibers of the sheet, fiber diameters and lengths of the constituent fibers, sheet thickness, basis weight, and the like. . When at least one of these is different, it is a “heterogeneous sheet”.

  The elastic member 43 (elastic filament) constituting the ventral outer layer sheet 31A is made of, for example, a thermoplastic elastomer or rubber. In particular, when a thermoplastic elastomer is used as a raw material, it is possible to perform melt spinning using an extruder in the same manner as a normal thermoplastic resin, and the elastic filament thus obtained is easily heat-sealed. It is suitable for. Examples of the thermoplastic elastomer include styrene such as SBS (styrene-butadiene-styrene), SIS (styrene-isoprene-styrene), SEBS (styrene-ethylene-butadiene-styrene), and SEPS (styrene-ethylene-propylene-styrene). -Based elastomers, olefin-based elastomers (ethylene-based α-olefin elastomers, propylene-based elastomers copolymerized with ethylene, butene, octene, etc.), polyester-based elastomers, polyurethane-based elastomers, and the like. Two or more kinds can be used in combination. Further, core-sheath type or side-by-side type composite fibers made of these resins can also be used.

  Thus, while the ventral outer layer sheet 31A and the back outer layer sheet 31C have stretchability, the crotch outer layer sheet 31B and the inner layer sheet 32 do not have stretchability and are non-stretchable. The non-stretchable sheets 31B and 32 preferably do not have stretchability in the vertical direction X or the horizontal direction Y, and preferably do not have stretchability in both the directions X and Y. In the exterior body 3, the outer layer sheet 31 in which only a part (the abdominal part 1 </ b> A and the back part 1 </ b> C) is stretchable and the inner layer sheet 32 that is not stretchable as a whole are the parts having the stretchability of the outer layer sheet 31 ( Under the stretched state of the ventral outer layer sheet 31A and the dorsal outer layer sheet 31C), they are bonded to each other on the opposing surfaces. Therefore, the outer package 3 as a whole is provided with the ventral outer layer sheet 31A and the dorsal outer layer sheet 31C. The ventral portion A and the dorsal side portion C (the waistline portion) are stretchable in at least the stretchable direction (lateral direction Y) of both sheets 31A and 31C, and the other portion (the ventral side in the crotch B) The portion other than the portion 1A and the back side portion 1C. The central portion in the longitudinal direction X of the crotch portion 1B) does not have elasticity.

  The fact that the sheet is not substantially stretchable in a certain direction means that the sheet hardly stretches even when a force for pulling in the certain direction is applied to the sheet. For example, when a sample having a length of 15 × width of 5 cm is pulled in a longitudinal direction by a material tensile tester such as Tensilon and the breaking elongation when the sample breaks is 10% or less, The sample is not substantially stretchable in the longitudinal direction. The elongation at break can be calculated by (the sample length at break−the original length of the sample) / (the original length of the sample) × 100.

  As the non-stretching crotch outer layer sheet 31B and the inner layer sheet 32, nonwoven fabrics produced by various manufacturing methods are preferably used, for example, spunbond nonwoven fabric, air-through nonwoven fabric, needle punched nonwoven fabric, and the like. As a constituent fiber of the nonwoven fabric used as the non-stretchable sheets 31B and 32, for example, a fiber made of polyester such as polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyamide, or the like Etc. The fibers constituting the nonwoven fabric used as the non-stretchable sheets 31B and 32 may be short fibers or long fibers, and may be hydrophilic or water repellent. Moreover, a core-sheath type or side-by-side type composite fiber, a split fiber, a modified cross-section fiber, a crimped fiber, a heat-shrinkable fiber, or the like can also be used. These fibers can be used alone or in combination of two or more.

  The exterior body 3 includes a waist elastic member 33 that forms a waist gather at the opening edge of the waist opening WH. That is, one or a plurality of waist elastic members 33 for forming waist gathers (in the present embodiment, a plurality of waist elastic members 33) in the lateral direction of the waist edge WH of the waist opening WH in each of the ventral side A and the back side C. It is arranged in an extended state over the entire length of Y, whereby an annular waist gather that is substantially continuous over the entire circumference is formed in the waist opening WH. The waist elastic member 33 has a thread shape or a belt shape, and is sandwiched and fixed by an adhesive between the outer layer sheet 31 and the inner layer sheet 32 constituting the exterior body 3.

  Moreover, the exterior body 3 is a leg elastic member that forms leg gathers at the opening edge of each of the pair of leg openings LH, LH, and is one or a plurality (in this embodiment) arranged in an extended state on the front body F A plurality of front leg elastic members 34 and one or a plurality (in the present embodiment, a plurality) of rear leg elastic members 35 arranged in an extended state on the back body R are provided. As shown in FIGS. 2, 3 and 5, the front leg elastic member 34 and the rear leg elastic member 35 are spaced apart from each other in the longitudinal direction X, and the separation region exists in the crotch 1B. . Each of the leg elastic members 34 and 35 is thread-like or belt-like, and is sandwiched and fixed by an adhesive between the outer layer sheet 31 and the inner layer sheet 32 constituting the exterior body 3. As a result, annular leg gathers that are substantially continuous over the entire circumference are formed at the opening edges of the pair of leg openings LH and LH. The leg elastic members 34 and 35 are arranged in an extended state so that elastic stretchability is expressed at least at the outer portion in the lateral direction Y from both side edges along the longitudinal direction X of the absorbent main body 2, and At least the central part in the lateral direction Y of the site where the absorbent main body 2 exists is not arranged in a state where the elastic stretchability is expressed.

  In FIG. 7, the skin facing surface side of the absorbent core 23 is shown enlarged. The absorbent core 23 includes a two-layer structure including an upper absorbent core 230 and a lower absorbent core 231 disposed on the non-skin facing surface side of the upper absorbent core 230. The upper layer absorbent core 230 has a vertically long shape in which the front side in the longitudinal direction X (portion near the ventral portion 1A) is wider than the other portions in plan view, and is longer in the longitudinal direction X than the lower layer absorbent core 231. In the lower layer absorbent core 231, the length in the lateral direction Y is shorter than the length of the narrowest narrowest portion having the shortest length (width) in the lateral direction Y. The lower layer absorbent core 231 is a planar hourglass in which the central portion in the longitudinal direction X is shorter in the length (width) in the lateral direction Y than the front and rear end portions (both longitudinal end portions), and the central portion in the longitudinal direction X is constricted. The size (area) in plan view is larger than that of the upper absorbent core 230. The entire upper absorbent core 230 overlaps with the lower absorbent core 231 in plan view, and the lower absorbent core 231 forms the outline of the absorbent core 23. The upper absorbent core 230 is located on the skin-facing surface of the lower absorbent core 231 at a position biased slightly closer to the ventral portion 1A than the center in the longitudinal direction X of the lower absorbent core 231. The upper absorbent core 230 and the lower absorbent core 231 may be joined to each other by an adhesive, but in the present embodiment, they are not joined together, and they are not integral and separable. Has been made.

The basis weight of the upper absorbent core 230 is preferably 150 g / cm ² or more, more preferably 200 g / cm ² or more, and preferably 400 g / cm ² or less, more preferably 350 g / cm ² or less, more specifically. Is preferably 150 g / cm ² or more and 400 g / cm ² or less, more preferably 200 g / cm ² or more and 350 g / cm ² or less.
The basis weight of the lower layer absorbent core 231 is preferably 150 g / cm ² or more, more preferably 200 g / cm ² or more, and preferably 400 g / cm ² or less, more preferably 350 g / cm ² or less, more specifically. Is preferably 150 g / cm ² or more and 400 g / cm ² or less, more preferably 200 g / cm ² or more and 350 g / cm ² or less.

When pulp is used as the material for forming the upper absorbent core 230, the basis weight of the pulp is preferably 75 g / cm ² or more, more preferably 100 g / cm ² or more, and preferably 200 g / cm ² or less. More preferably, it is 175 g / cm < ² > or less, More specifically, Preferably it is 75-200 g / cm < ² >, More preferably, it is 100-175 g / cm < ² >.
When pulp is used as the material for forming the lower absorbent core 231, the basis weight of the pulp is preferably 75 g / cm ² or more, more preferably 100 g / cm ² or more, and preferably 200 g / cm ² or less. More preferably, it is 175 g / cm ² or less, more specifically, preferably 75 g / cm ² or more and 200 g / cm ² or less, more preferably 100 g / cm ² or more and 175 g / cm ² or less.

When a water-absorbing polymer is used as a material for forming the upper absorbent core 230, the basis weight of the water-absorbing polymer is preferably 75 g / cm ² or more, more preferably 100 g / cm ² or more, and preferably 200 g. / Cm ² or less, more preferably 175 g / cm ² or less, more specifically, preferably 75 g / cm ² or more and 200 g / cm ² or less, more preferably 100 g / cm ² or more and 175 g / cm ² or less.
When a water-absorbing polymer is used as the material for forming the lower layer absorbent core 231, the basis weight of the water-absorbing polymer is preferably 75 g / cm ² or more, more preferably 100 g / cm ² or more, and preferably 200 g. / Cm ² or less, more preferably 175 g / cm ² or less, more specifically, preferably 75 g / cm ² or more and 200 g / cm ² or less, more preferably 100 g / cm ² or more and 175 g / cm ² or less.

  As shown in FIG. 7, the lower layer absorbent core 231 has constant width regions P1, P2, and P3 whose side edges 231S and 231S extend linearly in parallel with the longitudinal direction X. The front width constant region P1 is located at the front end portion in the vertical direction X of the lower layer absorbent core 231 (vertical end portion on the abdominal side portion 1A side), and the central width constant region P2 is the vertical direction of the lower layer absorbent core 231. Positioned at the center of X (vertical end on the abdominal side 1A side), the constant rear width region P3 is the rear end (vertical direction on the back side 1C side) of the longitudinal direction X of the lower layer absorbent core 231. (End). The constant front width region P1 is located on the abdominal side 1A, the constant central width region P2 is located on the crotch 1B, and the constant rear width region P3 is located on the back side 1C. Among these three constant width regions P1, P2 and P3, the longest length in the vertical direction X is the central constant width region P2, and the front constant width region P1 and the rear constant width region P3 The latter is longer in the vertical direction X.

  Further, the lower layer absorbent core 231 has a constant central width region P2 at the center in the vertical direction X and a constant front width region P1 and a constant rear width region P3 at the front and rear end portions in the vertical direction X. Further, both side edges 23S, 23S of the lower layer absorbent core 231 have width change regions Q1, Q2 extending in a direction intersecting both the vertical direction X and the horizontal direction Y. The front width change region Q1 is located between the constant front width region P1 and the constant central width region P2, and the rear width change region Q2 is located between the constant rear width region P3 and the constant central width region P2. doing. The front width change region Q1 is located near the boundary between the abdominal side portion 1A and the crotch portion 1B or near the boundary in the abdominal side portion 1A, and the rear width change region Q2 is between the back side portion 1C and the crotch portion 1B. It is located near the boundary in the vicinity of the boundary or in the crotch 1B. In the front width change region Q1, both side edges 231S and 231S of the lower layer absorbent core 231 are inward in the vertical direction X and in the horizontal direction Y starting from the boundary between the constant front width region P1 and the front width change region Q1. The rear side width changing region Q2 extends inwardly in the vertical direction X and in the horizontal direction Y starting from the boundary between the constant rear width region P3 and the rear side width changing region Q2. It extends obliquely inward and is straight in both areas Q1 and Q2. Since the lower layer absorbent core 231 forms the outline of the absorbent core 23, both side edges 231 </ b> S and 231 </ b> S of the lower layer absorbent core 231 are also both side edges along the longitudinal direction X of the absorbent core 23.

  A narrow central opening 5 penetrating the lower absorbent core 231 in the thickness direction is formed at the central portion in the lateral direction Y of the lower absorbent core 231 so as to extend in the vertical direction X. A pair of narrow side openings 6, 6 penetrating the lower layer absorbent core 231 in the thickness direction on both outer sides in the lateral direction Y of the part 5 extend in the longitudinal direction X and the central opening 5 (diaper 1 Is symmetric with respect to a horizontal center line Ly) extending in the vertical direction X so as to be divided into two in the horizontal direction Y. Each of these openings 5 and 6 is a space where no absorbent core-forming material exists, and is arranged in the crotch 1B. These openings 5 and 6 are all narrow, that is, the length (width) in the horizontal direction Y is shorter than the length in the vertical direction X, and preferably the length in the horizontal direction Y is the length in the vertical direction X. It is 1/5 or less of this. The central opening 5 continuously extends on the horizontal center line Ly from the central width constant region P2 of the lower layer absorbent core 231 to the rear width change region Q2, and has a rectangular shape in plan view. Each of the pair of side openings 6 and 6 is located entirely in the central width constant region P2 and continuously extends in the vertical direction X. In the plan view, the lower base (side longer than the upper base) Is an isosceles trapezoidal shape located on the outer side in the lateral direction Y. In the side opening 6 having an isosceles trapezoidal shape in plan view, the outer edge 6S2 is the lower base of the trapezoid and the inner edge 6S1 is the upper base of the trapezoid. The central opening 5 has a longer length in the vertical direction X than the side openings 6, and the front and rear ends 5 </ b> F and 5 </ b> R of the central opening 5 in the vertical direction X are front and rear ends 6 </ b> F in the vertical direction X of the side openings 6. , 6R is located outward in the vertical direction X.

  On the other hand, the upper absorbent core 230 is formed with an opening that extends through the upper absorbent core 230 in the thickness direction and extends in the vertical direction X in a region overlapping the central opening 5 of the lower absorbent core 231 in plan view. Absent. In the present embodiment, the upper absorbent core 230 includes the upper absorbent core 230 not only in a region overlapping the central opening 5 of the lower absorbent core 231 in a plan view but also in other regions other than the region. Are not formed in the opening (the space in which no absorbent core forming material exists) extending in the thickness direction.

  In a plan view as shown in FIG. 7, the upper absorbent core 230 and the central opening 5 overlap each other, and the central opening 5 extends over the entire length in the longitudinal direction X of the upper absorbent core 230. In the present embodiment, both the front end 5F and the rear end 5R in the longitudinal direction X of the central opening 5 extend outward in the longitudinal direction X from the front and rear ends in the longitudinal direction X of the upper absorbent core 230. The extension length of the rear end 5R side is longer than the front end 5F side.

  Thus, the absorptive core 23 (lower layer absorptive core 231) in the diaper 1 of the present embodiment has one central opening 5 and a pair of side openings 6 and 6 in the crotch 1B. The plurality of openings have an opening parallel region R1 in which the plurality of openings are aligned in the vertical direction X. The opening parallel region R1 extends over the entire length in the vertical direction X of the separation region in which the front leg elastic member 34 and the rear leg elastic member 35 are spaced apart from each other in the vertical direction X.

  The diaper 1 of this embodiment is a three-dimensional gather having one central opening 5 and a pair of side openings 6 and 6 in the absorbent core 23, and a base end portion 27 on the skin facing surface side of the absorbent core 23. 24 and the above-mentioned configuration that “the elastic member 26 for forming a three-dimensional gather and the absorbent core 23 overlap in a plan view when the diaper 1 is unfolded and extended” As shown in FIG. 8, the absorbent core 23 in the portion 1B is bent in a W shape so that the central opening 53 is a peak and the side opening 6 is a valley in a cross-sectional view along the lateral direction Y. To do. In addition, the code | symbol 100 in FIG. 8 is a crotch part of the wearer of the diaper 1. FIG. Further, from the viewpoint of easy explanation, in FIG. 8, illustration of a part of the constituent members of the diaper 1 (exterior body 3 and the like) is omitted.

  That is, when the diaper 1 is pulled up to the crotch part of the wearer with both feet of the wearer inserted into the pair of leg opening leg openings LH and LH in the wearing operation of the diaper 1, the elastic for forming a three-dimensional gather Due to the contraction of the member 26, the pair of three-dimensional gathers 24, 24 stands up toward the wearer's crotch, whereby both sides along the longitudinal direction X of the absorbent core 23 (lower layer absorbent core 231) are skin facing surfaces. Stand up to bend to the side. At this time, in the opening parallel region R1, the both side portions of the lower layer absorbent core 231 positioned outward in the lateral direction Y from the pair of side openings 6 and 6 rise so as to bend toward the skin facing surface side, Since the rising both sides compress the central part of the lower layer absorbent core 231 sandwiched between the pair of side openings 6 and 6 in the lateral direction Y, the lower layer absorbent core 231 has a length in the lateral direction Y. This causes a so-called width shrinkage. The central portion of the lower absorbent core 231 that has undergone width shrinkage has a central opening 53, and is a part of a two-layer structure portion (middle high portion) on which the upper absorbent core 230 is superimposed. At some point, only the lower layer side of the two-layer structure portion is compressed in the lateral direction Y, so that the entire thickness direction of the two-layer structure portion is folded into a mountain fold at the central opening portion 5, and the central opening portion 5 is positioned. The center part of the horizontal direction Y of the two-layer structure part to bulge up toward a wearer's excretion part. As a result, the absorbent core 23 in the opening parallel region R1 is formed such that the central opening 53 is a peak and the side opening 6 is a valley in a cross-sectional view along the lateral direction Y as shown in FIG. , Bent into a W shape.

  In particular, the upper absorbent core 230 in this embodiment is not formed with an opening that extends through the upper absorbent core 231 in the thickness direction and extends in the vertical direction X. The two-layer structure portion with the absorbent core 231 is easily bent into a mountain fold at the central opening 5, and therefore, the W-shaped bending deformation of the absorbent core 23 is likely to occur, and the deformed shape is easily maintained. Yes. In particular, if the opening is formed in a region overlapping the central opening 5 in the upper absorbent core 230, the two-layer structure portion of the absorbent core 23 may be folded into a valley fold, and the diaper 1 is worn. In addition, there is a possibility that it cannot be mounted in an ideal shape in terms of improving leakage prevention.

  From the viewpoint of facilitating W-shaped deformation by inducing mountain folds of the two-layer structure portion (middle and high portions) of the absorbent core 23, the central opening 5 and the exterior body 3 expand and contract in the lateral direction Y in plan view. It is preferable that the part which has property overlaps. As described above, in the present embodiment, the portion having the stretchability in the lateral direction Y in the exterior body 3 is a portion in which the ventral outer layer sheet 31A or the back outer layer sheet 31C is disposed, In view, the central opening 5 preferably overlaps with the arrangement region of both sheets 31A and 31C, and particularly preferably overlaps with the ventral side 1A and / or the back side 1C.

  The W-shaped deformation of the absorbent core 23 occurs during the wearing operation of the diaper 1, and the deformed shape is maintained even after the absorbent core 23 is worn on the wearer's crotch. Since the absorbent core 23 bends in a W shape at the crotch part 1B of the diaper 1, the absorbent core 23 is flexibly deformed by the pressure applied from the wearer's thigh. The pressure applied to the skin and the resistance and discomfort caused by the pressure are reduced, and a good wearing feeling can be obtained. In particular, both side portions along the longitudinal direction X of the absorbent main body 2 are easy to contact with the thighs of the wearer of the diaper 1 and are portions that greatly affect the wearing feeling. Moreover, since the upper layer absorbent core 230 is not included and the thickness is relatively thin, it is difficult for the wearer to feel uncomfortable wearing, and the wearing comfort of the diaper 1 is improved. In addition, both side portions of the absorbent core 23 (portions positioned outward in the lateral direction Y from the pair of side opening portions 6 and 6) stand up, and the end portions thereof are the wearer's skin, preferably the ridge portion. Since the pair of three-dimensional gathers 24 and 24 are fitted along the wearer's ridge part by being positioned along, a good leakage prevention property is also obtained. In short, the diaper 1 of the present embodiment can be obtained by simply deforming the absorbent core 23 into a W-shape by simply attaching it to the human crotch portion according to a conventional method, thereby causing the lateral side of the crotch portion 1B including the middle and high portions. Since the center part of the direction Y closely adheres to the excretion part of the wearer without gaps or wrinkles, and the pair of three-dimensional gathers 24, 24 fit along the wearer's ridge part, it is applied to the crotch part. It is possible to achieve both ease and good wearing feeling and stable absorption performance (leakage prevention performance).

  Moreover, in this embodiment, as shown in FIG.2, FIG3 and FIG.7, the upper layer absorptive core 230 and a pair of side opening parts 6 and 6 do not overlap in planar view, and naturally upper layer absorptivity. Since the core 230 and the both side portions of the lower layer absorbent core 231 positioned outward in the lateral direction Y rather than the both side opening portions 6 and 6 do not overlap, the both side portions are likely to rise, and the opening parallel region R1 described above The effects of the above and the like are more reliably exhibited.

  In the present embodiment, as shown in FIGS. 2, 3, and 7, the central opening 5 has a longer length in the vertical direction X than the side opening 6, so the central opening 5 and the side openings Not only in the opening parallel region R1 in which the portion 6 coexists, but also in the region in which only the central opening 5 exists, the two-layer structure portion (central portion in the lateral direction Y) of the absorbent core 23 is bent into a mountain fold and deformed. . In particular, the central opening 5 in the present embodiment extends outward in the vertical direction X from the rear end of the upper absorbent core 230 in the vertical direction X, and the rear end 5R of the extended portion is a side opening. 6 is located rearward in the longitudinal direction X from the rear end 6R, and therefore, the central portion in the lateral direction Y of the mountain-folded absorbent core 23 is located along the crack from the wearer's crotch. Therefore, the diaper 1 is easy to deform | transform according to the shape of a wearer's crotch part, and can express high fitting property.

  The effect of improving the fit, which is achieved by “the central opening 5 is longer in the longitudinal direction X than the side openings 6”, is “the lower absorbent core 231 has an hourglass shape (dumbbell in plan view). (That is, the central portion in the vertical direction X is shorter in the horizontal direction Y than the front and rear end portions (both end portions in the vertical direction)). Therefore, the diaper 1 of this embodiment provided with these both structures is excellent in fit property. Moreover, when the lower layer absorptive core 231 has an hourglass shape in a plan view, there is an effect that it is difficult for the absorbent core 23 to be twisted (unintentionally deformed) during the diaper 1 mounting operation.

The ratio of the length in the vertical direction X of the central opening 5 to the length in the vertical direction X of the side openings 6 (vertical length of the central opening 5 / vertical length of the side openings 6) is preferable. Is 1.01 or more, more preferably 1.2 or more, and preferably 1.5 or less, more preferably 1.4 or less, more specifically, preferably 1.01 or more and 1.5 or less, more preferably Is 1.2 or more and 1.4 or less.
The length in the longitudinal direction X of the central opening 5 is preferably 200 mm or more, more preferably 250 mm or more, and preferably 400 mm or less, more preferably 375 mm or less, more specifically, preferably 200 mm or more and 400 mm or less, More preferably, it is 250 mm or more and 375 mm or less.
The length in the longitudinal direction X of the side opening 6 is preferably 175 mm or more, more preferably 200 mm or more, and preferably 350 mm or less, more preferably 325 mm or less, more specifically, preferably 175 mm or more and 350 mm or less. More preferably, it is 200 mm or more and 325 mm or less.
In addition, like the side opening 6 in the present embodiment, when the length of the opening in the vertical direction X is not constant and the opening has a plurality of vertical lengths, the plurality of vertical The maximum value in the direction length is defined as the length in the vertical direction of the opening.

  The length (width) in the lateral direction Y of each of the central opening 5 and the side opening 6 is preferably 5 mm or more, more preferably 7.5 mm or more, and preferably 20 mm or less, more preferably 15 mm or less. More specifically, it is preferably 5 mm or more and 20 mm or less, more preferably 7.5 mm or more and 15 mm or less. The central opening 5 and the side opening 6 may have the same or different length in the lateral direction Y. In the present embodiment, the lengths in the lateral direction Y of both openings 5 and 6 are the same.

  During wearing of the diaper 1, the central portion in the lateral direction Y of the opening parallel region R1 of the absorbent core 23 in the crotch 1B, that is, a portion where the two-layer structure portion of the absorbent core 23 exists (middle and high portions), and wearing From the viewpoint of improving the adhesion with the body (excretion part) of the person, the side edge 231S of the lower layer absorbent core 231 on each of one side and the other side in the lateral direction Y of the lower layer absorbent core 231 with respect to the lateral center line Ly. It is preferable that the distance W2 (see FIG. 7) between the side opening 6 and the central opening 5 is longer than the distance W1 (see FIG. 7) between the side opening 6 and the side opening 6. If the separation distance W2 is shorter than the separation distance W1, when the absorbent core 23 is deformed into a W shape, a space is formed between the middle and high portions and the wearer's body, which may reduce the adhesion. is there.

The ratio of the separation distance W1 and the separation distance W2 (separation distance W1 / separation distance W2) is preferably 0.4 or more, more preferably 0.5 or more, and preferably 0.8 or less, more preferably 0.8. 7 or less, more specifically, preferably 0.4 or more and 0.8 or less, and more preferably 0.5 or more and 0.7 or less.
The separation distance W1 is preferably 10 mm or more, more preferably 12.5 mm or more, and preferably 30 mm or less, more preferably 27.5 mm or less, more specifically, preferably 10 mm or more and 30 mm or less, more preferably 12 It is 5 mm or more and 27.5 mm or less.
The separation distance W2 is preferably 20 mm or more, more preferably 25 mm or more, and preferably 50 mm or less, more preferably 45 mm or less, more specifically, preferably 20 mm or more and 50 mm or less, more preferably 25 mm or more and 45 mm or less. is there.

  As shown in FIGS. 2, 3, and 7, the absorbent core 23 according to the present embodiment has front and rear ends in the longitudinal direction X of the absorbent core 23, that is, front and rear ends in the longitudinal direction X of the lower layer absorbent core 231. And a pair of cutout portions 7 and 7 cut inward in the longitudinal direction X. The notch 7 has a length (width) in the lateral direction Y that decreases inward in the longitudinal direction X. One and the other of the pair of notches 7, 7 have the same shape and the same size in plan view. The notch 7 in the present embodiment has a V-shape in plan view, and the width gradually decreases as it goes inward in the longitudinal direction X. The top part (V-shaped top part) of the notch part 7 is located on the extension line (lateral center line Ly) of the central opening part 5. Since the notch portions 7 are formed at the front and rear ends in the longitudinal direction X of the absorbent core 23, the two-layer structure portion (the central portion in the lateral direction Y) of the absorbent core 23 is folded in a mountain when the diaper 1 is worn. Since it becomes easy to bend, the absorbent core 23 is easily deformed into a W shape, and the portions of the pair of cutout portions 7, 7 that are located outward in the lateral direction Y, that is, the corners of the absorbent core 23. Since the portion easily bends to the skin facing surface side, the absorbent core 23 is easily deformed into a boat shape that is easy to fit along the wearer's body, and as a result, fit can be improved.

  In this embodiment, the structure which can guide | induced the deformation | transformation to the boat-shaped shape of the absorptive core 23 at the time of wearing of the diaper 1 besides the notch part 7 is employ | adopted. That is, in the present embodiment, as shown in FIG. 7, each of the pair of side openings 6 and 6 has a longer length in the vertical direction X at the outer edge 6S2 than at the inner edge 6S1. In FIG. 1, the trapezoidal shape has an inner edge 6S1 as an upper base and an outer edge 6S2 as a lower bottom, and the longitudinal front and rear ends 6F and 6R start from the longitudinal ends of the outer edge 6S2, respectively. , Obliquely extending inward in the vertical direction X and inward in the horizontal direction Y. In the present embodiment, the front and rear ends 6F and 6R in the longitudinal direction X of the lateral openings 6 are respectively on one side and the other side in the lateral direction Y of the absorbent core 23 with respect to the lateral center line Ly. The width change regions Q1 and Q2 are located on the extension line of the side edge 231S of the lower layer absorbent core 231 (absorbent core 23). With such a configuration, when the diaper 1 is worn, the corners of the absorbent core 23 are more easily bent on the skin facing surface side, so that the absorbent core 23 can easily take a boat shape.

  Further, from the viewpoint of facilitating deformation of the absorbent core 23 into a boat shape, the elastic member 26 for forming a three-dimensional gather is a lower layer absorbent core in a plan view in a developed and extended state of the diaper 1 as shown in FIG. 231 (absorptive core 23) in the center direction constant region P2 at the center in the longitudinal direction X, outward in the lateral direction Y from the side edge 231S, and in the longitudinal direction X of the lower layer absorptive core 231 (absorbent core 23) Of the constant width regions P1 and P3 of the front and rear end portions, the inner side in the lateral direction Y than the side edge 231S in the longer side in the lateral direction Y (the side edge 231S is far from the lateral center line Ly) It is preferable that it is located in the direction. A region indicated by a symbol R2 in FIG. 7 corresponds to this. When the elastic member 26 for forming a three-dimensional gather is located in the region R2 in a plan view of the diaper 1 in the developed and extended state, the shape of the boat of the absorbent core 23 is promoted when the diaper 1 is worn, and the fit property Can be improved.

As mentioned above, although this invention was demonstrated based on the preferable embodiment, this invention is not restrict | limited to the said embodiment. For example, in the above-described embodiment, the outer layer sheet 31 is configured by combining a plurality of sheets. However, similarly to the inner layer sheet 32, the outer layer sheet 31 may be configured by one continuous sheet. Moreover, the exterior body 3 is divided | segmented into the exterior body ventral region located in a ventral side part, and the exterior body back side area | region located in a back side part, The absorptive main body 2 is the said exterior body ventral region, It may be bridged and fixed to the exterior body back side field.
In addition, the absorbent article of the present invention is not limited to pants-type disposable diapers, but broadly includes articles used for absorbing liquid discharged from the human body, such as unfolded disposable diapers, sanitary napkins, sanitary shorts, etc. Is included. The following additional notes are disclosed with respect to the embodiment of the present invention described above.

<1>
The abdomen has a liquid-retaining absorbent core, and has an abdominal part disposed on the abdomen side of the wearer, a back side part disposed on the dorsal side, and a crotch portion positioned therebetween, and the abdomen side part. An absorbent article having a longitudinal direction extending from the crotch portion to the back side portion and a transverse direction orthogonal thereto,
The absorbent core is configured to include a two-layer structure including an upper absorbent core and a lower absorbent core disposed on the non-skin facing surface side of the upper absorbent core,
A narrow central opening that penetrates the lower absorbent core in the thickness direction is formed at the lateral center of the lower absorbent core so as to extend in the vertical direction. On both outer sides, a pair of narrow lateral openings that penetrate the lower layer absorbent core in the thickness direction extend in the vertical direction and are formed symmetrically with respect to the central opening,
The upper absorbent core and the central opening overlap in plan view, and the central opening extends over the entire length in the longitudinal direction of the upper absorbent core,
The upper absorbent core is not formed with an opening extending in the longitudinal direction through the upper absorbent core in the thickness direction in a region overlapping the central opening of the lower absorbent core in plan view,
A pair of three-dimensional gathers that stand up toward the wearer's skin when worn are provided on the skin facing surface sides of the left and right side portions along the longitudinal direction of the absorbent core. The skin-facing surface side has a base end portion and stands up so as to form a free end on the skin side of the wearer, and the elastic member for forming a three-dimensional gather is arranged in a stretched state in the vertical direction at the free end,
The absorbent article in which the three-dimensional gather-forming elastic member and the absorbent core overlap each other in a plan view of the absorbent article in a developed and extended state.

<2>
The absorbent article according to <1>, wherein the upper absorbent core and the side opening do not overlap in plan view.
<3>
The absorbent article according to <1> or <2>, wherein the central opening is longer in the longitudinal direction than the side opening.
<4>
The lateral opening and the central opening are separated from each other by a distance between a side edge along the longitudinal direction of the lower absorbent core and the lateral opening on one side and the other side in the lateral direction of the lower absorbent core. The absorbent article as described in any one of said <1>-<3> whose separation distance with a part is longer.
<5>
The said lower layer absorptive core is an absorptive article as described in any one of said <1>-<4> whose length of a horizontal direction is shorter than each of the longitudinal direction front-and-back edge part.

<6>
The absorbent core has a pair of cutouts cut inward in the longitudinal direction from the longitudinal front and rear ends of the absorbent core,
The cutout portion has a lateral length that decreases inward in the vertical direction, and the top portion of the cutout portion is located on an extension line of the central opening portion in plan view. The absorbent article as described in any one of <5>.
<7>
The lower layer absorbent core has a constant width region in which both side edges of the lower layer absorbent core extend in parallel with the vertical direction at the front end portion, the center portion, and the rear end portion in the vertical direction, and the center in the vertical direction. A width-changing region extending in a direction in which both side edges of the lower layer absorbent core intersect with both the vertical direction and the horizontal direction between the constant width region of each part and the constant width region of the longitudinal front and rear end portions, respectively. And
The lateral opening is longer in the longitudinal direction at the outer edge than at the inner edge,
In each of the one side and the other side of the lower layer absorbent core, the longitudinal front and rear ends of the side openings are respectively located on the extension lines of the side edges of the lower layer absorbent core in the width change region. The absorbent article according to any one of <1> to <6>.
<8>
In a plan view of the absorbent article in the unfolded and extended state, the elastic member for forming a three-dimensional gather is laterally outward from the side edge in the constant width region of the central portion in the longitudinal direction of the absorbent core, and the absorption The absorbent article according to the above <7>, wherein in the constant width region of the longitudinal front and rear end portions of the adhesive core, the absorbent article is positioned inward in the lateral direction with respect to the side edge in the longer lateral direction.

<9>
The absorption according to any one of <1> to <8>, wherein a longitudinal rear end of the central opening extends outward in a longitudinal direction from a longitudinal rear end of the upper absorbent core. Sex goods.
<10>
Both the front end and the rear end in the vertical direction of the central opening extend outward in the vertical direction from the front and rear ends in the vertical direction of the upper absorbent core, and the extension length thereof is on the rear end side. The absorbent article according to any one of <1> to <8>, wherein the one is longer than the front end side.
<11>
<1> to <10>, wherein the crotch portion includes an opening parallel region in which the central opening and the pair of side openings are vertically aligned. Absorbent articles.
<12>
A longitudinal rear end of the central opening has an extending portion extending longitudinally outward from a longitudinal rear end of the upper absorbent core, and the rear end of the extending portion is the side. The absorbent article as described in any one of said <1>-<11> located in the back of the vertical direction rather than the rear end of a direction opening part.

<13>
The said lower layer absorptive core has an absorptivity as described in any one of said <1>-<12> whose length of a horizontal direction is shorter than the front-and-rear edge part (longitudinal both ends), respectively. Goods.
<14>
The upper absorbent core has any one of the above items <1> to <13>, in which the front side in the vertical direction (the portion near the abdomen side) is wider than the other portions in plan view. Absorbent article according to item.
<15>
<1> to <14, wherein the upper absorbent core is on a skin-facing surface of the lower absorbent core and is slightly biased toward the abdomen than the longitudinal center of the lower absorbent core. > The absorbent article as described in any one of>.

<16>
Any of the above <1> to <15>, comprising: an absorbent main body comprising the absorbent core; and an exterior body disposed on the non-skin facing surface side of the absorbent main body and fixing the absorbent main body An absorbent article according to any one of the above.
<17>
The said exterior body is an absorbent article as described in said <16> provided with the part which has a stretching property in a horizontal direction.
<18>
The absorbent article according to <17>, wherein in the plan view, the central opening and a portion having a stretchability in a lateral direction in the exterior body overlap each other.
<19>
The absorbent article according to any one of <16> to <18>, wherein the absorbent article is a pants-type disposable diaper.
<20>
Any of <16> to <19>, wherein the absorbent main body has a top sheet that forms a skin facing surface, a back sheet that forms a non-skin facing surface, and the absorbent core that is interposed between both sheets. An absorbent article according to any one of the above.

<21>
The said exterior body is an absorbent article as described in any one of said <16>-<20> comprised including the laminated body of an outer layer sheet and an inner layer sheet.
<22>
The outer layer sheet includes a ventral outer layer sheet constituting the ventral side part, a dorsal outer layer sheet constituting the dorsal side part, and a crotch outer layer sheet constituting the crotch part positioned between these sheets. The absorbent article according to <21>, which is configured to include.
<23>
The absorbent article according to <22>, wherein the ventral outer layer sheet and the back outer layer sheet have elasticity in a lateral direction.
<24>
The absorbent article according to <22> or <23>, wherein the crotch outer layer sheet and the inner layer sheet are not stretchable and do not have stretchability.
<25>
Any one of the above items <22> to <24>, wherein the ventral outer layer sheet and the back outer layer sheet have a configuration in which a thread-like elastic filament is bonded to one surface of an extensible fiber layer mainly composed of inelastic fibers. Absorbent article according to item.
<26>
The absorbent article according to any one of <22> to <25>, wherein the central opening overlaps with an arrangement region of any one of the ventral outer layer sheet and the back outer layer sheet in plan view. .

<27>
The absorbent article according to any one of <1> to <26>, wherein a surface of the absorbent core is covered with a core wrap sheet.
<28>
The basis weight of the upper absorbent core is preferably 150 g / cm ² or more, more preferably 200 g / cm ² or more, and preferably 400 g / cm ² or less, more preferably 350 g / cm ² or less, more specifically. Is preferably 150 g / cm ² or more and 400 g / cm ² or less, more preferably 200 g / cm ² or more and 350 g / cm ² or less, the absorbent article according to any one of <1> to <27>.
<29>
The basis weight of the lower layer absorbent core is preferably 150 g / cm ² or more, more preferably 200 g / cm ² or more, and preferably 400 g / cm ² or less, more preferably 350 g / cm ² or less, more specifically. Is preferably 150 g / cm ² or more and 400 g / cm ² or less, more preferably 200 g / cm ² or more and 350 g / cm ² or less, the absorbent article according to any one of <1> to <28>.

<30>
The vertical length of the central opening / the vertical length of the side opening, which is the ratio of the vertical length of the central opening to the vertical length of the side opening, is preferably 1.01 or more. More preferably 1.2 or more, and preferably 1.5 or less, more preferably 1.4 or less, more specifically preferably 1.01 or more and 1.5 or less, more preferably 1.2 or more. Absorbent article as described in any one of said <1>-<29> which is 1.4 or less.
<31>
The longitudinal length of the central opening is preferably 200 mm or more, more preferably 250 mm or more, and preferably 400 mm or less, more preferably 375 mm or less, more specifically, preferably 200 mm or more and 400 mm or less, more preferably Is an absorbent article according to any one of <1> to <30>, which is 250 mm or more and 375 mm or less.
<32>
The longitudinal length of the side opening is preferably 175 mm or more, more preferably 200 mm or more, and preferably 350 mm or less, more preferably 325 mm or less, more specifically, preferably 175 mm or more and 350 mm or less, The absorbent article according to any one of <1> to <31>, which is preferably 200 mm or more and 325 mm or less.
<33>
The lateral length of each of the central opening and the side opening is preferably 5 mm or more, more preferably 7.5 mm or more, and preferably 20 mm or less, more preferably 15 mm or less, more specifically, The absorbent article according to any one of <1> to <32>, preferably 5 mm to 20 mm, more preferably 7.5 mm to 15 mm.

<34>
A separation distance W1 / which is a ratio of a separation distance W1 between the side edge along the longitudinal direction of the lower layer absorbent core and the side opening and a separation distance W2 between the side opening and the central opening. The separation distance W2 is preferably 0.4 or more, more preferably 0.5 or more, and preferably 0.8 or less, more preferably 0.7 or less, more specifically preferably 0.4 or more and 0. The absorbent article according to any one of <1> to <33>, which is 0.8 or less, more preferably 0.5 or more and 0.7 or less.
<35>
The separation distance W1 is preferably 10 mm or more, more preferably 12.5 mm or more, and preferably 30 mm or less, more preferably 27.5 mm or less, more specifically, preferably 10 mm or more and 30 mm or less, more preferably The absorbent article according to <34>, which is 12.5 mm or more and 27.5 mm or less.
<36>
The separation distance W2 is preferably 20 mm or more, more preferably 25 mm or more, and preferably 50 mm or less, more preferably 45 mm or less, more specifically, preferably 20 mm or more and 50 mm or less, more preferably 25 mm or more and 45 mm or less. The absorbent article according to <34> or <35>, wherein
<37>
The central opening has a lateral length shorter than a longitudinal length, preferably any one of the above <1> to <36>, wherein the lateral length is 1/5 or less of the longitudinal length. Absorbent article as described in 1.
<38>
The lateral opening has a lateral length shorter than the longitudinal length, preferably any one of the above <1> to <37>, wherein the lateral length is not more than one fifth of the longitudinal length. Absorbent article according to item.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to such examples.

[Example 1]
According to a conventional method, a pants-type disposable diaper having a basic configuration similar to that of the diaper 1 shown in FIGS. SC250R with a basis weight of 25 g / m ² (Rengo Non-Woven Products Co., Ltd.) is used as the top sheet 21, and C3Y6020A5A with a basis weight of 20 g / m ² (Mitsubishi Resin Co., Ltd.) is used as the back sheet 22. As the body, an exterior body of a commercially available pants-type disposable diaper (trade name “Relief is a pants with relief relief” manufactured by Kao Corporation) was used. As the absorbent core forming material, pulp fibers and water-absorbing polymer particles were used, and these were mixed and piled according to a conventional method to obtain an upper absorbent core 230 and a lower absorbent core 231. When the absorbent core forming material is stacked in the manufacturing process of the lower layer absorbent core 231, a non-stacked portion of the absorbent core forming material is formed, and the central opening 5 and the side openings formed of the non-stacked fiber portion. 6 was formed on the lower absorbent core 231. The two absorbent cores 230 and 231 are laminated to obtain the two-layered absorbent core 23 shown in FIG. 7, which is covered with a core wrap sheet made of hydrophilic and liquid-permeable paper having a basis weight of 16 g / m ^2. Thus, an absorber was produced.

  The dimensions of the absorbent core used in Example 1 are as follows. The longitudinal length of the lower absorbent core is 520 mm, the maximum width of the lower absorbent core is 180 mm, the minimum width of the lower absorbent core is 140 mm, The thickness was 2.2 mm, the longitudinal length of the upper absorbent core was 230 mm, the maximum width of the upper absorbent core was 64 mm, the minimum width of the upper absorbent core was 50 mm, and the thickness of the upper absorbent core was 2.1 mm. It was. Moreover, in the lower layer absorbent core, the longitudinal length of the central opening was 340 mm, the width of the central opening was 10 mm, the longitudinal length of the side opening was 265 mm, and the width of the lateral opening was 10 mm. . Moreover, the separation distance W1 between the side edge of the lower layer absorbent core and the side opening was 20 mm, and the separation distance W2 between the side opening and the central opening was 35 mm.

[Comparative Example 1]
A pants-type disposable diaper was produced in the same manner as in Example 1 except that the absorbent core 90 having a single layer structure shown in FIG. 9A was used as the absorbent core. The absorptive core 90 is a pair of side absorptions extending in the longitudinal direction X and located outside the lateral direction Y of the central absorbent portion 91 having a plan view hourglass shape (dumbbell shape) and the constricted portion of the central absorbent portion 91. The space part (separation part) 93 in which an absorptive core formation material does not exist is interposed between the central absorbent part 91 and the pair of side absorbent parts 92, 92. . The space 93 is functionally the same as the opening. At the front and rear ends of the central absorbent portion 91 in the longitudinal direction X, a pair of cutout portions having a V shape in plan view is formed.
The dimensions of the absorbent core 90 used in Comparative Example 1 are that the longitudinal length of the central absorbent portion 91 is 580 mm, the maximum width of the central absorbent portion 91 is 180 mm, the minimum width of the central absorbent portion 91 is 140 mm, and the central absorbent portion 91 is. The side absorption part 92 has a thickness of 310 mm, the side absorption part 92 has a width of 33 mm, the side absorption part 92 has a thickness of 2.2 mm, and the space part 93 has a width (central absorption). The distance between the portion 91 and the side absorption portion 92) was 15 mm.

[Comparative Example 2]
A pants-type disposable diaper was produced in the same manner as in Example 1 except that the absorbent core 95 having a single-layer structure in a plan view hourglass shape (dumbbell shape) shown in FIG. 9B was used as the absorbent core. No opening is formed in the absorbent core 95.
The dimensions of the absorbent core 95 used in Comparative Example 2 were a longitudinal length of 460 mm, a maximum width of 200 mm, a minimum width of 120 mm, and a thickness of 6.5 mm.

  About the underpants type disposable diaper of an Example and a comparative example, the liquid absorption amount and the wearing feeling were evaluated by the following method. The results are shown in Table 1 below.

<Method for evaluating liquid absorption>
An adult model capable of injecting liquid from the excretion point into the diaper was used, and the pants-type disposable diaper to be evaluated was attached while the model was upright, and then the model was turned 90 degrees sideways. Next, 100 g of physiological saline was injected at a rate of 5 g / sec from the excretion point using a liquid discharge pump with a speed adjustment function. After leaving still for 10 minutes, it was confirmed visually whether there was any leakage. If there was no leakage, 100 g of physiological saline was repeatedly injected at a rate of 5 g / sec from the excretion point. When a leak occurred, the physiological saline injection was stopped, and the difference in the weight of the diaper before and after the injection was taken as the liquid absorption. It can be evaluated that the larger the measured value of the liquid absorption, the higher the absorption performance and the better the leakage prevention property.

<Evaluation method of wearing feeling>
After wearing the pants-type disposable diapers of the example and the comparative example, the wearing feeling was evaluated as it was without reworking for 5 subjects. After wearing, the subject asked to carry out desk work for 2 hours, and the wearing feeling of the diaper at that time was evaluated in five stages. The five-level evaluation is “Good: 5 points, Slightly good: 4 points, Neither: 3 points, Slightly bad: 2 points, Bad: 1 point”, and an average score of 4 points or more is ◎ 3 points or more ○ Two or more points were evaluated as Δ, and less than two points as ×.

1 Pants-type disposable diaper (absorbent article)
2 Absorbent body 21 Top sheet 22 Back sheet 23 Absorbent core 230 Upper layer absorbent core 231 Lower layer absorbent core 231S Side edges P1, P2, P3 of lower layer absorbent core (absorbent core) Constant width region of lower layer absorbent core Q1, Q2 Width change region 24 of lower layer absorbent core 24 Three-dimensional gather 26 Three-dimensional gather forming elastic member 27 Three-dimensional gather base 3 Exterior body 31 Outer layer sheet 31A Ventral outer layer sheet (elastic sheet)
31B Crotch outer layer sheet (non-elastic sheet)
31C Backside outer layer sheet (elastic sheet)
32 Inner layer sheet (non-elastic sheet)
33 Waist elastic member 34 Front leg elastic member 35 Rear leg elastic member 5 Center opening 6 Side opening 7 Notch F Front body R Rear body 1A Abdominal side (front waist part)
1B Crotch 1C Back side (back waist part)
X Vertical direction Y Horizontal direction

Claims (8)

The abdomen has a liquid-retaining absorbent core, and has an abdominal part disposed on the abdomen side of the wearer, a back side part disposed on the dorsal side, and a crotch portion positioned therebetween, and the abdomen side part. An absorbent article having a longitudinal direction extending from the crotch portion to the back side portion and a transverse direction orthogonal thereto,
The absorbent core is configured to include a two-layer structure including an upper absorbent core and a lower absorbent core disposed on the non-skin facing surface side of the upper absorbent core,
A narrow central opening that penetrates the lower absorbent core in the thickness direction is formed at the lateral center of the lower absorbent core so as to extend in the vertical direction. On both outer sides, a pair of narrow lateral openings that penetrate the lower layer absorbent core in the thickness direction extend in the vertical direction and are formed symmetrically with respect to the central opening,
The upper absorbent core and the central opening overlap in plan view, and the central opening extends over the entire length in the longitudinal direction of the upper absorbent core,
The upper absorbent core is not formed with an opening extending in the longitudinal direction through the upper absorbent core in the thickness direction in a region overlapping the central opening of the lower absorbent core in plan view,
A pair of three-dimensional gathers that stand up toward the wearer's skin when worn are provided on the skin facing surface sides of the left and right side portions along the longitudinal direction of the absorbent core. The skin-facing surface side has a base end portion and stands up so as to form a free end on the skin side of the wearer, and the elastic member for forming a three-dimensional gather is arranged in a stretched state in the vertical direction at the free end,
The absorbent article in which the three-dimensional gather-forming elastic member and the absorbent core overlap each other in a plan view of the absorbent article in a developed and extended state.   The absorptive article according to claim 1 in which said upper layer absorptive core and said side opening do not overlap in plane view.   The absorbent article according to claim 1 or 2, wherein the central opening is longer in the longitudinal direction than the side opening.   The lateral opening and the central opening are separated from each other by a distance between a side edge along the longitudinal direction of the lower absorbent core and the lateral opening on one side and the other side in the lateral direction of the lower absorbent core. The absorptive article according to any one of claims 1 to 3 whose distance from a part is longer.   The absorbent article according to any one of claims 1 to 4, wherein the lower layer absorbent core has a longitudinal central portion that is shorter in the lateral direction than the longitudinal front and rear end portions. The absorbent core has a pair of cutouts cut inward in the longitudinal direction from the longitudinal front and rear ends of the absorbent core,
The notch has a lateral length that decreases inward in the longitudinal direction, and the top of the notch is located on an extension line of the central opening in plan view. The absorbent article as described in any one of these. The lower layer absorbent core has a constant width region in which both side edges of the lower layer absorbent core extend in parallel with the vertical direction at the front end portion, the center portion, and the rear end portion in the vertical direction, and the center in the vertical direction. A width-changing region extending in a direction in which both side edges of the lower layer absorbent core intersect with both the vertical direction and the horizontal direction between the constant width region of each part and the constant width region of the longitudinal front and rear end portions, respectively. And
The lateral opening is longer in the longitudinal direction at the outer edge than at the inner edge,
In each of the one side and the other side of the lower layer absorbent core, the longitudinal front and rear ends of the side openings are respectively located on the extension lines of the side edges of the lower layer absorbent core in the width change region. The absorptive article according to any one of claims 1 to 6.   In a plan view of the absorbent article in the unfolded and extended state, the elastic member for forming a three-dimensional gather is laterally outward from the side edge in the constant width region of the central portion in the longitudinal direction of the absorbent core, and the absorption The absorptive article according to claim 7 which is located in the horizontal direction inward rather than the side edge in the direction where the length of a horizontal direction is longer among the constant width fields of the longitudinal direction front and rear end part of a property core.

Images