Pad

Abstract

[Problem] To provide a pad in which is formed a large space for retaining excrement such as urine in the pad, and which makes it possible to prevent excrement that could not be absorbed by an absorbent body from leaking to the outside past a three-dimensional gathering. [Solution] A pad provided with a liquid-permeable top sheet, a liquid-impermeable back sheet, and an absorbent body between the top sheet and the back sheet, wherein: three-dimensional gatherings that extend in the front-rear direction are fixed at both side parts of the top sheet in the width direction; the absorbent body is formed with a high-stiffness region and a low-stiffness region that is more easily deformable than the high-stiffness region; the low-stiffness region is provided surrounding the outer periphery of the high-stiffness region; and the thickness of the low-stiffness region is greater than the thickness of the high-stiffness region.

Description

Pad

[0001] The present invention relates to a pad to be attached to the inner surface of a disposable diaper such as a pant-type diaper.

[0002] The pad is formed by sequentially laminating a liquid-permeable top sheet, a second sheet for promptly transferring the liquid that has permeated the top sheet to the absorber, and the absorber in order from the inner side. Furthermore, three-dimensional gathers rising from the inner surface of the top sheet are provided on both side portions in the width direction of the top sheet to block the movement of excrement in the width direction and prevent side leakage.

[0003] In recent years, many inventions have been disclosed for pads that increase the urine absorption capacity and absorption rate through various improvements to the absorber. For example, Patent Document 1 discloses a technique in which high-rigidity regions are respectively formed in the front portion, the intermediate portion, and the rear portion of the absorber, and low-rigidity regions are formed on both sides in the width direction of the high-rigidity region in the intermediate portion. In addition, Patent Document 2 discloses a technique in which the outer periphery of a grid-formed low-rigidity region is surrounded by a high-rigidity region.

[0004] Patent Document 3 discloses a technique in which a rigidity difference sheet including a high-rigidity portion and a low-rigidity portion is provided below the absorber. In addition, Patent Document 4 discloses a technique in which the front portion and the rear portion of the pad are folded into three toward the top sheet side.

[0005] Japanese Patent No. 7097260 Japanese Patent No. 5670960 Utility Model Registration No. 3238579 Japanese Patent No. 6944575

[0006] However, with the techniques of Patent Documents 1 to 4, when the pad is worn, both side portions in the width direction of the inner surface of the pad become mountain-folded. Therefore, especially when the wearer is in the supine position or lateral position, there is a risk that excrement such as urine that cannot be absorbed by the absorber may leak out to the outside beyond the three-dimensional gathers.

[0007] Accordingly, an object of the present invention is to provide a pad that can form a large space for storing excrement such as urine in the pad, and can suppress excrement that cannot be absorbed by the absorber from leaking out to the outside beyond the three-dimensional gathers.

[0008] The means for solving the above problems are as follows. The first means is a pad comprising a liquid-permeable top sheet, a liquid-impermeable back sheet, and an absorbent between the top sheet and the back sheet, characterized in that three-dimensional gathers extending in the front-rear direction are fixed to both sides of the top sheet in the width direction, the absorbent is formed with a high-rigidity region and a low-rigidity region that is more easily deformed than the high-rigidity region, the low-rigidity region is provided around the outer periphery of the high-rigidity region, and the thickness of the low-rigidity region is formed to be greater than the thickness of the high-rigidity region.

[0009] The second means is characterized in that, in the first means, the length of the high-rigidity region in the front-rear direction is formed to be 65% or more of the length of the upright portion of the three-dimensional gather.

[0010] The third means is characterized in that, in the second means, the length in the width direction of the high-rigidity region is formed to be 30 mm or more, which is the width of the labia of a woman, and 75 mm or less, which is the width of the groin of a man.

[0011] The fourth means is characterized in that, in the third means, the left portion of the high-rigidity region is formed in an arc shape that protrudes to the right, and the right portion is formed in an arc shape that protrudes to the left.

[0012] The fifth means is characterized in that, in the fourth means, in a plan view, the portion located dorsally to the center line in the front-rear direction of the high-rigidity region is formed to be larger than the portion located ventrally to the center line in the front-rear direction, or the portion located ventrally to the center line in the front-rear direction of the high-rigidity region is formed to be larger than the portion located dorsally to the center line in the front-rear direction.

[0013] The sixth means is characterized in that, in the fifth means, the low-rigidity region located to the left of the high-rigidity region is raised to the upper left, and the low-rigidity region located to the right of the high-rigidity region is raised to the upper right.

[0014] The seventh means is characterized in that, in any one of the means of the first to sixth paragraphs, the basis weight of the high-rigidity region is formed to be larger than the basis weight of the low-rigidity region.

[0015] The eighth means is characterized in that, in any one of the means of the first to sixth claims, the spacing between the embossments formed in the high-rigidity region is smaller than the spacing between the embossments formed in the low-rigidity region.

[0016] According to the first method, three-dimensional gathers extending in the front-to-back direction are fixed to both sides of the width direction of the top sheet, the absorbent body is formed with a high-rigidity region and a low-rigidity region that is more easily deformed than the high-rigidity region, the low-rigidity region is provided around the outer periphery of the high-rigidity region, and the thickness of the low-rigidity region is made thicker than the thickness of the high-rigidity region. As a result, starting from the rigidity boundary between the high-rigidity region and the low-rigidity region, the pad has a valley-fold structure with the high-rigidity region at the bottom and the low-rigidity regions located on both sides of the high-rigidity region rising upward along the groin area. Therefore, a large space is formed to store excrement such as urine, and it is possible to suppress the leakage of excrement that could not be absorbed by the absorbent body through the three-dimensional gathers to the outside.

[0017] According to the second method, in addition to the effects of the first method, the length of the high-rigidity region in the front-to-back direction is formed to be 65% or more of the length of the upright portion of the three-dimensional gather, so that a larger space can be formed for storing excrement such as urine.

[0018] According to the third method, in addition to the effects of the second method, the widthwise length of the high-rigidity region is formed to be 30 mm or more, which is the width of a woman's labia, and 75 mm or less, which is the width of a man's crotch, so that the pad can be attached in close contact with the wearer's crotch.

[0019] According to the fourth method, in addition to the effects of the third method, the left side of the high-rigidity region is formed in an arc shape that protrudes to the right, and the right side is formed in an arc shape that protrudes to the left, so that the pad can be attached more closely to the wearer's crotch. Also, the wearer's leg pressure makes it easier to form a valley fold structure with the high-rigidity region as the bottom along the rigidity boundary.

[0020] According to the fifth means, in addition to the effects of the fourth means, in a plan view, the portion located dorsally to the center line in the anterior-posterior direction in the high-rigidity region is formed to be larger than the portion located ventrally to the center line in the anterior-posterior direction, or the portion located ventrally to the center line in the high-rigidity region is formed to be larger than the portion located dorsally to the center line in the anterior-posterior direction, so that leakage of excrement from the dorsal or ventral side is more suppressed when the patient is lying supine or on their side.

[0021] According to the sixth method, in addition to the effects of the fifth method, the low-rigidity region located to the left of the high-rigidity region rises to the upper left, and the low-rigidity region located to the right of the high-rigidity region rises to the upper right, thereby forming an even larger space for storing excrement.

[0022] According to the seventh means, in addition to the effects of any one of the first to sixth means, the basis weight of the high-rigidity region is formed to be larger than that of the low-rigidity region, so that the high-rigidity region and the low-rigidity region can be easily formed.

[0023] According to the eighth means, in addition to the effects of any one of the first to sixth means, the spacing between the embossed areas formed in the high-rigidity region is smaller than the spacing between the embossed areas formed in the low-rigidity region, so that the high-rigidity region and the low-rigidity region can be easily formed.

[0024] This is an inner surface plan view of the pad. This is an outer surface plan view of the pad. This is a plan view of the pad according to the first embodiment. This is a cross-sectional view taken along line A-A in Figure 3. This is a plan view of the pad according to the second embodiment. This is a plan view of the pad according to the third embodiment. This is a plan view of the pad according to the fourth embodiment. This is a plan view of the pad according to the fifth embodiment. This is a schematic diagram showing the mounting state of the pad in the cross-sectional view taken along line A-A.

[0025] The present invention will now be described below with reference to the drawings, based on preferred embodiments thereof. As shown in Figures 1 to 3, the pad 100 installed inside the pants-type disposable diaper is formed from, in order from the inner side facing the body, a liquid-permeable top sheet 11, a second sheet 20 that has a faster liquid permeation rate than the top sheet 11, an absorbent body 12 that absorbs liquid, a liquid-impermeable back sheet 13, an outer sheet 14 made of nonwoven fabric or the like, and three-dimensional gathers 15 provided on both sides in the width direction of the absorbent body 12.

[0026] The absorbent body 12 has a constricted portion 12D formed approximately in the center of its longitudinal direction, corresponding to the wearer's crotch area. For convenience, in this specification, the portion of the absorbent body 12 that is longitudinally in front of the constricted portion 12D, corresponding to the wearer's front body, is referred to as the front body portion 12C, and the portion of the absorbent body 12 that is longitudinally in rear of the constricted portion 12D, corresponding to the wearer's back body, is referred to as the back body portion 12E.

[0027] A rectangular front locking member 18A, having a longer side in the width direction, is provided on the outer surface of the outer sheet 14 corresponding to the front end of the front body portion 12C of the absorbent body 12, and a rectangular rear locking member 18B, having a longer side in the width direction, is provided on the outer surface of the outer sheet 14 corresponding to the rear end of the rear body portion 12E of the absorbent body 12. The front locking member 18A and the rear locking member 18B are collectively referred to as the locking member 18.

[0028] <Pad of the First Embodiment> As shown in Figure 3, the absorbent body 12 has a high-rigidity region 12A and a low-rigidity region 12B that is relatively less rigid than the high-rigidity region 12A. The high-rigidity region 12A is located in the center of the absorbent body 12 in the width direction, and the low-rigidity region 12B is located adjacent to the high-rigidity region 12A in the front-to-back and width directions. The high-rigidity region 12A is the region facing the wearer's urination area. In the absorbent body 12, the region other than the high-rigidity region 12A can be designated as the low-rigidity region 12B.

[0029] The length of the high-rigidity region 12A in the front-to-back direction is formed to be at least 65% of the length of the upright region 15a of the three-dimensional gather 15, which is indicated by the diagonal lines. The upright region 15a of the three-dimensional gather 15 is the portion of the three-dimensional gather 15 excluding the fixed region in the front-to-back direction. If the length of the high-rigidity region 12A in the front-to-back direction is too short compared to the upright region 15a of the three-dimensional gather 15, the maximum volume that can store excrement such as urine will be reduced. On the other hand, if the length exceeds the upright region 15a of the three-dimensional gather 15, a gap will be created between the high-rigidity region 12A and the skin, allowing excrement such as urine to leak out. Therefore, it is more preferable to make the length of the high-rigidity region 12A in the front-to-back direction the same as the length of the upright region 15a of the three-dimensional gather 15.

[0030] The width of the high-rigidity region 12A is preferably formed to be between 30 mm and 75 mm. This value is calculated from the average dimensions of the width of the labia of women and the width of the crotch of men. By setting the width of the high-rigidity region 12A within this range, the pad can be fitted tightly to the crotch area of ​​the wearer.

[0031] The low-rigidity region 12B is a region of the absorber 12 other than the high-rigidity region 12A, and is located adjacent to the high-rigidity region 12A in the front-to-back and width directions. Therefore, the length of the low-rigidity region 12B in the front-to-back and width directions is the same as that of the absorber 12.

[0032] As shown in Figure 4, the thickness 31t in the thickness direction of the high-rigidity region 12A is smaller than the thickness 32t in the thickness direction of the low-rigidity region 12B. With this configuration, a concave shape is formed in the absorber 12 with the high-rigidity region 12A as the bottom and the low-rigidity region 12B as the wall.

[0033] Furthermore, a rigidity boundary 40 exists between the high-rigidity region 12A and the low-rigidity region 12B. This rigidity boundary 40 is the starting point where the low-rigidity region 12B deforms upward along the groin when external forces are applied from both legs of the wearer or when urination occurs.

[0034] The high-rigidity region 12A and the low-rigidity region 12B may be bonded together with adhesive or heat fusion, but it is more preferable that they be integrally molded to have continuity that allows for the smooth movement of excretions such as urine.

[0035] By adopting the above configuration, a difference in rigidity occurs at the rigidity boundary 40 between the high-rigidity region 12A and the low-rigidity region 12B. Therefore, as shown in Figure 9, when the pad 100 is attached, this rigidity boundary 40 acts as a starting point, and the low-rigidity region 12B tends to stand up along the groin area due to the leg pressure at the time of attachment. The low-rigidity region 12B located to the left of the high-rigidity region 12A stands up to the upper left, and the low-rigidity region 12B located to the right of the high-rigidity region 12A stands up to the upper right, causing the pad 100 to form a valley-fold structure. As a result, a large space is created between the skin surface and the surface of the pad 100 to store excretions such as urine. At this time, the absorbent body 12 also becomes concave, so the absorbent surface of the pad 100 is lower than the three-dimensional gathers 15.

[0036] In this state, if urination occurs, even if urine or other excrement is produced that cannot be absorbed by the high-rigidity region 12A, which is the region opposite the urinary opening, the low-rigidity region 12B, which is standing above, acts as a wall and can further absorb the urine or other excrement. Furthermore, because the absorbent surface is located lower than the three-dimensional gathers 15, even when used in a supine or lateral position, it is possible to suppress leakage of urine or other excrement beyond the three-dimensional gathers 15 to the outside.

[0037] Furthermore, the thickness 31t in the thickness direction of the high-rigidity region 12A is preferably 2.0 to 19 mm, more preferably 5.0 to 14 mm, in order to provide appropriate absorbency while enabling the valley-fold structure of the pad 100.

[0038] <Pad of the second embodiment> As shown in Figure 5, an embossed surface is formed in the high-rigidity region 12A, either without heating or with heating (lattice pattern portion). Note that the same reference numerals are used for the same components as in the pad 100 of the first embodiment, and their descriptions are omitted.

[0039] This allows the high-rigidity region 12A to be easily compressed in the thickness direction. Since no embossing is formed in the low-rigidity region 12B, a difference in rigidity is created between the high-rigidity region 12A and the low-rigidity region 12B, making it easier to form a valley fold structure along the inguinal region starting from the rigidity boundary 40.

[0040] As other aspects of the high-rigidity region 12A having higher rigidity than the low-rigidity region 12B, there may be mentioned an aspect in which the basis weight is larger than that of the low-rigidity region 12B, an aspect in which the density is larger than that of the low-rigidity region 12B, and the like.

[0041] <Pad of Third Embodiment> As shown in FIG. 6, the high-rigidity region 12A is formed in an arc shape with a left portion protruding toward the right side, and is formed in an arc shape with a right portion protruding toward the left side. That is, both side edges of the high-rigidity region 12A are shaped to be constricted along the circumference of the wearer's legs. The same members as those of the pad 100 of the first embodiment are denoted by the same reference numerals, and descriptions thereof are omitted.

[0042] Accordingly, when an external force is received from both legs of the wearer, the external force is easily transmitted to the pad 100. As a result, the low-rigidity region 12B rises further upward along the rigidity boundary portion 40, which makes it easier for the pad 100 to form a valley-fold structure along the groin. Furthermore, the pad 100 can be worn while being more closely attached to the crotch portion of the wearer.

[0043] <Pad of Fourth Embodiment> As shown in FIG. 7, in a plan view of the high-rigidity region 12A, a portion of the high-rigidity region 12A located on the dorsal side of the center line in the front-rear direction LD is formed larger than a portion located on the ventral side of the center line in the front-rear direction LD. Alternatively, a portion of the high-rigidity region 12A located on the ventral side of the center line in the front-rear direction LD may be formed larger than a portion located on the dorsal side of the center line in the front-rear direction LD. That is, in the front-rear direction of the pad 100, the volume capable of storing excrement such as urine differs between the ventral side and the dorsal side. The same members as those of the pad of the first embodiment are denoted by the same reference numerals, and descriptions thereof are omitted.

[0044] Thereby, even in the supine position or lateral position, leakage of excrement to the outside from the dorsal side or the ventral side can be further suppressed. In addition, since the length in the width direction of the high-rigidity region 12A differs in the front-rear direction of the pad 100, external force is easily transmitted to the rigidity boundary portion 40, and a valley-fold structure starting from the rigidity boundary portion 40 is easily formed.

[0045] <Pad of the Fifth Embodiment> As shown in Figure 8, a low-rigidity region 12B is formed in the outer periphery and the center in the width direction of the high-rigidity region 12A. Note that the same reference numerals are used for the same components as in the pad of the first embodiment, and their descriptions are omitted.

[0046] As a result, the rigid boundary portion 40 exists not only on the outer periphery of the high-rigidity region 12A, but also in the center of the high-rigidity region 12A in the width direction. Consequently, starting from the rigid boundary portion 40, the low-rigidity region 12B on the outer periphery of the high-rigidity region 12A becomes more likely to form a valley-fold structure that rises upward along the groin area.

[0047] Next, the materials and characteristics of the top sheet 11 will be explained in order. (Top sheet) As the top sheet 11, perforated or non-perforated nonwoven fabric or porous plastic sheet is preferred. The material fibers constituting the nonwoven fabric can be synthetic fibers such as polyethylene or polypropylene (olefin-based), polyester, or polyamide, as well as regenerated fibers such as rayon or cupro, or natural fibers such as cotton. Nonwoven fabrics obtained by appropriate processing methods such as the spunlace method, spunbond method, thermal bond method, meltblown method, or needle punch method can be used. Among these processing methods, the spunlace method is excellent in terms of flexibility and drape, and the thermal bond method is excellent in terms of bulkiness and softness. When a large number of perforations are formed in the top sheet 11, urine and the like are absorbed quickly, resulting in excellent dry touch properties. Furthermore, the front and rear ends of the top sheet 11 in the longitudinal direction extend further in the front and rear direction than the front and rear ends of the absorber 12 in the longitudinal direction and are fixed to the front and rear ends of the back sheet 13 in the longitudinal direction, and the left and right ends of the top sheet 11 in the width direction extend further in the left and right direction than the left and right ends of the absorber 12 in the width direction and are fixed to the left and right ends of the back sheet 13 in the width direction.

[0048] Top sheet 11 has a fineness of approximately 2-15 dtex and a basis weight of 10-45 g / m. ２ A nonwoven fabric of a certain degree can be used. Furthermore, in order to prevent loose stool from remaining on the top sheet 11, it is preferable that at least the surface of the top sheet 11 is water-repellent or hydrophobic.

[0049] (Second Sheet) In order to quickly transfer the liquid that has permeated through the top sheet 11 to the absorbent 12, a second sheet 20 can be provided on the back side of the top sheet 11, which has a faster liquid permeation rate than the top sheet 11. This second sheet 20 is intended to quickly transfer the liquid to the absorbent 12, enhance the absorption performance of the absorbent 12, and prevent the "backflow" phenomenon of the absorbed liquid from the absorbent 12. The second sheet 20 can also be omitted.

[0050] Examples of the second sheet 20 include the same material as the top sheet 11, as well as spunlace nonwoven fabric, spunbond nonwoven fabric, SMS nonwoven fabric, pulp nonwoven fabric, a mixed sheet of pulp and rayon, point-bond nonwoven fabric, or crepe paper. Air-through nonwoven fabric is particularly preferred due to its bulkiness. For air-through nonwoven fabric, it is preferable to use a composite fiber with a core-sheath structure. In this case, the resin used for the core may be polypropylene (PP), but polyester (PET), which has high rigidity, is preferred. The basis weight is 17 to 80 g / m². ２ Preferably, 25 to 60 g / m ２ This is more preferable. The thickness of the raw fibers for the nonwoven fabric is preferably 2.0 to 10 dtex. In order to make the nonwoven fabric bulky, it is also preferable to use off-center fibers without a core in the center, hollow fibers, or off-center and hollow fibers as all or part of the mixed fibers of the raw fibers.

[0051] In the illustrated configuration, the second sheet 20 is shorter than the width of the absorbent material 12 and positioned in the center, but it may also be provided across the entire width. The length of the second sheet 20 in the front-to-back direction may be the same as the total length of the diaper, or the same as the length of the absorbent material 12.

[0052] It is desirable to fix the second sheet 20 to the adjacent member on the back side using a joining method that involves material welding, such as heat sealing or ultrasonic sealing, or by hot melt adhesive, in order to prevent misalignment with the member on the back side. In the illustrated example, the second sheet 20 is fixed to the surface of the portion of the absorber 12 located on the front side by hot melt adhesive applied to its back surface.

[0053] (Absorbent) The absorbent 12 is preferably a porous structure (including interfiber gaps) in which absorbent material is aggregated. Hydrophilic fibers such as pulp fibers are preferably used as the absorbent material, and superabsorbent polymers (SAP) in particulate form may be mixed in as needed to ensure the amount of absorption. The basis weight of the pulp fibers is, for example, 100 to 450 g / m². ２ It can be considered to be of a certain degree.

[0054] Suitable superabsorbent polymers include carboxymethylcellulose, polyacrylic acid and its salts, acrylate polymer crosslinks, starch-acrylic acid graft copolymers, hydrolysates of starch-acrylonitrile graft copolymers, polyoxyethylene crosslinks, carboxymethylcellulose crosslinks, polyethylene oxide, partially crosslinked water-expanding polymers such as polyacrylamide, or copolymers of isobutylene and maleic acid. Products to which an anti-blocking agent has been added to suppress blocking due to moisture absorption can also be used. Superabsorbent polymers can also exist in various forms such as powder, particulate, granular, pellet, sol, suspension, gel, film, and nonwoven fabric, all of which can be used in the present invention, with particulate polymers being particularly preferred. Suitable superabsorbent polymer particles have a water absorption rate of 70 seconds or less, particularly 40 seconds or less. If the water absorption rate is too slow, so-called backflow occurs, where the liquid supplied into the absorbent body 12 flows back out of the absorbent body 12. Furthermore, as the superabsorbent polymer particles, those with a gel strength of 1000 Pa or more are preferably used. This effectively suppresses stickiness after liquid absorption, even when a bulky absorbent material 12 is used. The basis weight of the superabsorbent polymer can be determined as appropriate, but as an example, when intended for absorbing loose stools in nursing care applications, 50 to 200 g / m² is used. ２ It can be done this way.

[0055] The ratio of fibers to superabsorbent polymer particles in the absorbent material 12 is not particularly limited; for example, the ratio of fibers to superabsorbent polymer particles by weight can be 40:60 to 65:35.

[0056] The thickness of the absorbent 12 is not particularly limited, but can be 1 to 30 mm, preferably 2 to 19 mm, and more preferably 5 to 14 mm.

[0057] The length of the constricted portion 12D in the longitudinal direction is formed to be 20-50% of the length of the absorbent body 12 in the longitudinal direction, and the narrowest width of the constricted portion 12D in the width direction is formed to be 40-80% of the width of the absorbent body 12 in the width direction. This allows the pad to adhere closely to the wearer and improves the fit performance. Figures 1 and 2 show an absorbent body 12 with a roughly hourglass shape in which the constricted portion 12D is formed approximately in the center in the longitudinal direction, but it is also possible to form it in a rectangular shape or the like without forming the constricted portion 12D. Also, Figures 1 and 2 show a form in which the length of the front body portion 12C is formed to be shorter than the length of the rear body portion 12E in the longitudinal direction, but the length of the front body portion 12C and the rear body portion 12E can also be the same length.

[0058] (Backsheet) The sheet located on the back side of the absorbent 12 is called the backsheet 13. As the backsheet 13, an impermeable plastic sheet such as polyethylene or polypropylene is used, but in recent years, a sheet that is permeable to moisture is preferred in order to prevent stuffiness. A water-impermeable and permeable sheet is a microporous sheet obtained by melt-kneading an inorganic filler into an olefin resin such as polyethylene or polypropylene to form a sheet, and then stretching it in a uniaxial or biaxial direction. Furthermore, the front and rear ends in the longitudinal direction of the backsheet 13 extend in the front and rear direction beyond the front and rear ends in the longitudinal direction of the absorbent 12 and are fixed to the front and rear ends in the longitudinal direction of the outer sheet 14, and the left and right ends in the width direction of the backsheet 13 extend in the left and right direction beyond the left and right ends in the width direction of the absorbent 12 and are fixed to the left and right ends in the width direction of the outer sheet 14.

[0059] (Outer sheet) The material of the outer sheet 14 is not particularly limited, but examples include plastic films made of olefin resins such as polyethylene and polypropylene, laminated nonwoven fabrics with a plastic film on the surface of a nonwoven fabric, and laminated sheets made by layering and bonding a nonwoven fabric to a plastic film. It is preferable to use a material that is both impermeable to liquids and permeable to liquids for the outer sheet 14, which is preferred from the viewpoint of preventing stuffiness. As a moisture-permeable plastic film, a microporous plastic film obtained by kneading an inorganic filler into an olefin resin such as polyethylene and polypropylene, forming a sheet, and then stretching it in a uniaxial or biaxial direction is widely used. In addition, sheets that are made impermeable to liquids without using a plastic film can also be used as the outer sheet 14 by methods such as using a nonwoven fabric made of microdenier fibers, strengthening leak resistance by reducing the voids in the fibers by applying heat or pressure, or coating with a superabsorbent resin or hydrophobic resin or water repellent agent.

[0060] (Three-dimensional gather) The three-dimensional gather 15 is formed from a base fixed to the widthwise side of the outer sheet 14 and a main body extending from the base beyond the widthwise side of the absorber 12, etc., to the inner side of the top sheet 11. The front and rear ends in the longitudinal direction of the main body are fixed to the top sheet 11, while the central part in the longitudinal direction of the main body is not fixed to the top sheet 11 and stands upright toward the inner surface. The three-dimensional gather 15 is formed from a gather sheet 16 and an elongated gather elastic member 17 that extends in the longitudinal direction.

[0061] (Gathered Sheet) The gathered sheet 16 can be made of SMS nonwoven fabric (SMS, SSMMS, etc.), olefin-based materials such as polyethylene or polypropylene, polyester-based materials, amide-based synthetic fibers, regenerated fibers such as rayon and cupro, or natural fibers such as cotton. Nonwoven fabrics obtained by appropriate processing methods such as spunbonding, thermal bonding, meltblown, or needle punching can be used, but it is especially preferable to use a nonwoven fabric with a low basis weight and excellent breathability to prevent stuffiness. Furthermore, for the gathered sheet 16, it is preferable to use a water-repellent treated nonwoven fabric coated with a silicone-based, paraffinic metal-based, alkylchromic cloid-based water-repellent agent, etc., in order to prevent the permeation of urine, etc., prevent rashes, and enhance the feel on the skin (dryness).

[0062] (Gathered Elastic Member) As the gathered elastic member 17, materials such as styrene rubber, olefin rubber, urethane rubber, ester rubber, polyurethane, polyethylene, polystyrene, styrene-butadiene, silicone, and polyester, which are commonly used, can be used. Furthermore, in order to make it difficult to see from the outside, it is preferable that the thickness be 925 dtex or less, the elongation rate be 150 to 350%, and the spacing be 10.0 mm or less. Gathered elastic members 17 can be provided one at a time, or multiple at a time. The gathered elastic member 17 causes the three-dimensional gathers 15 to stand up toward the inner surface by its elastic force, and can be used in the form of threads or in the form of tapes with a predetermined width. The elongation rate is calculated as length when stretched / length of natural length × 100 [%].

[0063] (Locking Member) The locking member 18 is preferably a hook material of a mechanical fastener. The hook material can be in any shape, such as (A) L-shape, (B) J-shape, (C) mushroom-shaped, (D) T-shape, or (E) double J-shape (a shape in which two J-shaped pieces are joined back to back). Alternatively, an adhesive layer can be used instead of the hook material.

[0064] (Joining means) Adjacent members in the thickness direction are joined at appropriate locations or over the entire surface. For example, the top sheet 11 and the second sheet 20, and the second sheet 20 and the absorber 12 are joined at a part of the opposing surface (a dotted pattern, etc.) or over the entire surface. Hot melt adhesive can be used as a joining means to join each member. Hot melt adhesive can be applied by known methods such as slot application, continuous linear or dotted bead application, spiral or Z-shaped spray application, or pattern coating (transfer of hot melt adhesive using a relief printing method). Alternatively or in conjunction with this, at the fixing portion of the elastic member, hot melt adhesive can be applied to the outer surface of the elastic member to fix the elastic member to the adjacent member. Examples of hot melt adhesives include EVA-based, adhesive rubber-based (elastomer-based), olefin-based, and polyester / polyamide-based adhesives, but they can be used without particular limitation. As a joining means to join each component, material welding means such as heat sealing or ultrasonic sealing can also be used.

[0065] (Nonwoven fabric) As the nonwoven fabric mentioned above, known nonwoven fabrics can be used as appropriate depending on the part and purpose. The constituent fibers of the nonwoven fabric can be selected without particular limitation, including synthetic fibers such as polyethylene or polypropylene (olefin-based), polyester-based, and polyamide-based (including single-component fibers as well as composite fibers such as core-sheaths), as well as regenerated fibers such as rayon and cupro, and natural fibers such as cotton, and these can also be used in mixtures. 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 may be hydrophilic fibers (including hydrophilic fibers that have become hydrophilic with a hydrophilizing agent), hydrophobic fibers, or water-repellent fibers (including water-repellent fibers that have become water-repellent with a water-repellent agent). Furthermore, nonwoven fabrics are generally classified according to the length of the fibers, the sheet formation method, the fiber bonding method, and the lamination structure into short fiber nonwoven fabrics, long fiber nonwoven fabrics, spunbond nonwoven fabrics, meltblown nonwoven fabrics, spunlace nonwoven fabrics, thermal bond (air-through) nonwoven fabrics, needle punch nonwoven fabrics, point bond nonwoven fabrics, and laminated nonwoven fabrics (such as SMS nonwoven fabrics and SMMS nonwoven fabrics, which have a meltblown layer sandwiched between spunbond layers), and any of these nonwoven fabrics can be used.

[0066] The present invention can be used not only for the pad-type disposable diapers described above, but also for all types of absorbent articles, such as tape-type disposable diapers and pant-type disposable diapers.

[0067] <Explanation of Terms in the Specification> When the following terms are used in this specification, they have the following meanings unless otherwise specified in the specification.

[0068] "MD direction" and "CD direction" refer to the flow direction (MD direction) and the transverse direction (CD direction) perpendicular to it in the manufacturing equipment. One of these is the front-to-back direction of the product, and the other is the width direction of the product. The MD direction of a nonwoven fabric is the direction of the fiber orientation of the nonwoven fabric. Fiber orientation is the direction in which the fibers of the nonwoven fabric run. For example, it can be determined by a measurement method that conforms to the fiber orientation test method by zero-distance tensile strength of the TAPPI standard method T481, or by a simple measurement method that determines the fiber orientation direction from the ratio of tensile strength in the front-to-back and width directions.

[0069] "Front-to-back direction" refers to the direction indicated by the symbol LD in the diagram (vertical direction), and "width direction" refers to the direction indicated by WD in the diagram (left-to-right direction). The front-to-back direction and the width direction are perpendicular to each other.

[0070] "Front side" refers to the side that is closer to the wearer's skin when worn, while "back side" refers to the side that is further away from the wearer's skin when worn.

[0071] "Surface" refers to the side of the material that is closer to the wearer's skin when worn, while "back" refers to the side that is further away from the wearer's skin when worn.

[0072] "Unfolded state" refers to a state in which something is unfolded flat without contraction or sagging.

[0073] "Elongation rate" refers to the value relative to the natural length, which is set at 100%. For example, an elongation rate of 200% is equivalent to an elongation ratio of 2.

[0074] "Weight" is measured as follows: After pre-drying the sample or test piece, leave it in a test room or apparatus under standard conditions (temperature 23±1°C, relative humidity 50±2%) to reach a constant weight. Pre-drying means bringing the sample or test piece to a constant weight in an environment of 100°C. Note that pre-drying is not necessary for fibers with an official moisture content of 0.0%. Using a sample-taking template (100 mm × 100 mm), cut out a sample measuring 100 mm × 100 mm from the test piece that has reached a constant weight. Measure the weight of the sample, multiply it by 100 to calculate the weight per square meter, and this is the weight.

[0075] "Thickness" was measured using an automatic thickness measuring instrument (KES-G5 handy compression tester) with a load of 0.098 N / cm. ２ , and pressure area: 2 cm ２ Automatic measurement is performed under these conditions.

[0076] Unless otherwise specified, the dimensions of each part refer to the dimensions in the unfolded state, not the natural length state.

[0077] Unless otherwise specified, the tests and measurements shall be conducted in a test room or apparatus under standard conditions (temperature 23±1°C, relative humidity 50±2%).

[0078] The present invention can be used not only for the pad-type disposable diapers described above, but also for tape-type disposable diapers, pant-type disposable diapers, and other absorbent articles in general.

[0079] 11...Top sheet, 20...Second sheet, 12...Absorber, 12A...High rigidity region, 12B...Low rigidity region, 12C...Front section, 12D...Constricted section, 12E...Rear section, 13...Back sheet, 14...Outer sheet, 15...Three-dimensional gather, 15a...Three-dimensional gather standing region, 16...Gathered sheet, 17...Gathered elastic member, 18...Locking member, 31t...Thickness in the thickness direction of the high rigidity region, 32t...Thickness in the thickness direction of the low rigidity region, 40...Rigidity boundary, LD...Front-to-back direction, WD...Width direction.

Claims

1. A pad comprising a liquid-permeable top sheet, a liquid-impermeable back sheet, and an absorbent between the top sheet and the back sheet, characterized in that three-dimensional gathers extending in the front-rear direction are fixed to both sides of the top sheet in the width direction, the absorbent is formed with a high-rigidity region and a low-rigidity region that is more easily deformed than the high-rigidity region, the low-rigidity region is provided around the outer periphery of the high-rigidity region, and the thickness of the low-rigidity region is formed to be greater than the thickness of the high-rigidity region.

2. The pad according to claim 1, wherein the length of the high-rigidity region in the front-rear direction is formed to be 65% or more of the length of the upright portion of the three-dimensional gather.

3. The pad according to claim 2, wherein the widthwise length of the high-rigidity region is formed to be 30 mm or more, which is the width of the labia of a woman, and 75 mm or less, which is the width of the crotch of a man.

4. The pad according to claim 3, wherein the left portion of the high-rigidity region is formed in an arc shape that protrudes to the right, and the right portion is formed in an arc shape that protrudes to the left.

5. The pad according to claim 4, wherein, in a plan view, the portion located dorsally to the center line in the anterior-posterior direction within the high-rigidity region is formed to be larger than the portion located ventrally to the center line in the anterior-posterior direction, or the portion located ventrally to the center line in the anterior-posterior direction within the high-rigidity region is formed to be larger than the portion located dorsally to the center line in the anterior-posterior direction.

6. The pad according to claim 5, wherein when the pad is installed, the low-rigidity region located to the left of the high-rigidity region stands up to the upper left, and the low-rigidity region located to the right of the high-rigidity region stands up to the upper right.

7. The pad according to any one of claims 1 to 6, wherein the basis weight of the high-rigidity region is formed to be larger than that of the low-rigidity region.

8. The pad according to any one of claims 1 to 6, wherein the spacing of the embossing formed in the high-rigidity region is smaller than the spacing of the embossing formed in the low-rigidity region.

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