Absorbent articles

Abstract

To provide a thin absorbent article which includes an absorbent sheet capable of sufficiently exhibiting an absorption capacity of a high absorbent polymer, enables a plurality of times of body liquid absorption, hardly causes leakage, and has excellent fitness.SOLUTION: An absorbent article 50 which comprises a liquid permeable top sheet 10, a liquid impermeability back sheet 30, and an absorbent sheet 20 arranged therebetween is such that: the absorbent sheet 20 comprises two hydrophilic sheets 15, 16, and high absorbent polymer particles 12 held therebetween; the two hydrophilic sheets 15, 16 have a fusion part for joining them; and the fusion part separately has a central fusion part 21 continuing in the longitudinal direction in a center in the width direction of the absorbent sheet 20, two both side fusion parts 22 continuing in the longitudinal direction on both sides in the width direction of the absorbent sheet 20, and an X-shaped fusion part 23 with an X-shape in plane view, crossing the central fusion part 21 and the both side fusion parts 22 in the longitudinal direction.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to absorbent articles.

Background Art

[0002] Absorbent articles generally include a liquid-permeable topsheet, a liquid-impermeable backsheet, and an absorber disposed therebetween, and absorb and hold body fluids such as urine that have passed through the topsheet with the absorber, and are configured such that the body fluid does not contact the wearer's clothes or the like with the backsheet. Absorbent articles include, for example, pad products such as light incontinence pads, light incontinence liners, urine absorption pads, sanitary napkins, and paper diaper products such as pant-type paper diapers and tape-fastened paper diapers, and there are various forms depending on the application, and they are widely used regardless of whether the user is an infant, an adult, or an elderly person.

[0003] One of the recent problems with absorbent articles is the provision of a thin absorbent article that is not conspicuous when worn, has no sense of discomfort when worn, and gives no feeling of being worn. When designing a thin absorbent article, usually, thinning of the absorber, which occupies most of the absorbent article, is considered, and many absorbent articles using a thin absorber have been proposed.

[0004] Patent Document 1 describes a pant-type absorbent article including an outer body and an absorber fixed to the outer body, wherein the absorber has an absorbent sheet including two sheets of the same or different fiber sheets and particles of an absorbent polymer disposed between the fiber sheets (Claim 1). According to Patent Document 1, it is described that a thin and well-fitting absorbent sheet is provided (paragraph 0008).

[0005] Patent Document 2 describes an absorbent article comprising an absorbent body and a liquid-permeable top sheet disposed on the surface side of the absorbent body, wherein the absorbent body includes a cell absorbent sheet having a liquid-permeable upper sheet and a lower sheet, a cell surrounded by a joint between the upper sheet and the lower sheet where the upper sheet and the lower sheet are unjointed portions, and a powder containing superabsorbent polymer particles contained within this cell, and the upper sheet is a superabsorbent nonwoven fabric with a Klem water absorption of 100 mm or more (Claim 1). Furthermore, the specification describes an embodiment in which a hexagonal joint in plan view is connected in the longitudinal and width directions (Figures 1, 6, and 7). Klem water absorption is a value measured by the "Paper and cardboard - Water absorption test method - Klem method" specified in JIS P8141:2004. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 2021-104151 [Patent Document 2] Japanese Patent Publication No. 2021-052901 [Overview of the project] [Problems that the invention aims to solve]

[0007] As described in Patent Documents 1 and 2, an absorbent sheet comprising two hydrophilic sheets (such as hydrophilic nonwoven fabrics) and superabsorbent polymer particles sandwiched between them is known, and by using this absorbent sheet, a thin absorbent article with good fit can be obtained.

[0008] However, since absorbent articles are worn so that they extend from the wearer's lower abdomen through the groin to the buttocks, the absorbent sheet described in Patent Document 1 has the problem that the distribution of superabsorbent polymer particles within the absorbent sheet tends to be uneven. In the current situation where absorbent articles are required to absorb bodily fluids multiple times, the superabsorbent polymer particles on the surface bind together during the first absorption of bodily fluids, solidifying while containing the superabsorbent polymer particles that can absorb bodily fluids, which reduces the rate of absorption and prevents the material from fully exhibiting its absorption capacity. As a result, leakage of bodily fluids is likely to occur.

[0009] Furthermore, in the embodiment described in Patent Document 2, in which hexagonal joints in plan view are connected in the longitudinal and width directions, although the uneven distribution of superabsorbent polymer particles enclosed within the space surrounded by relatively small hexagonal joints is reduced, the amount of superabsorbent polymer particles that can be enclosed in a single space, and thus the amount of bodily fluid absorbed, is relatively small. Since bodily fluids do not flow evenly through the hexagonal spaces inside the absorbent sheet, similar to Patent Document 1, the rate and capacity for bodily fluid absorption decrease, making bodily fluid leakage more likely.

[0010] The object of the present invention is to provide a thin absorbent article that includes an absorbent sheet capable of fully utilizing the body fluid absorption capacity of highly absorbent polymer particles, is capable of absorbing body fluids multiple times, is less prone to leakage, and has a good fit. [Means for solving the problem]

[0011] The inventors of the present invention have conducted extensive research to solve the above problems and have found that by providing a predetermined fusion portion (the fusion portion of the two hydrophilic nonwoven fabrics) in an absorbent sheet comprising two hydrophilic nonwoven fabrics and superabsorbent polymer particles sandwiched between them, the uneven distribution of the superabsorbent polymer particles inside can be suppressed even when the absorbent sheet is worn and tilted. Furthermore, they have found that a desired absorbent article can be obtained by using this absorbent sheet, thus completing the present invention. That is, the present invention relates to the following absorbent article.

[0012] (1) An absorbent article comprising a liquid-permeable top sheet, a liquid-impermeable back sheet, and an absorbent sheet disposed between them, The absorbent sheet comprises two hydrophilic sheets and a superabsorbent polymer sandwiched between them. The two hydrophilic sheets have a fusion joint that joins them together. The fused portion is, The central fused portion of the absorbent sheet is continuous in the longitudinal direction, The absorbent sheet has two fused portions on both sides in the width direction that are continuous in the longitudinal direction, An absorbent article having, at a distance from each other, a central fused portion and an X-shaped fused portion in a plan view that intersects the longitudinal direction with the two side fused portions. (2) The absorbent article of (1) above, wherein the central fused portion and the X-shaped fused portion intersect only at the center in the width direction of the central fused portion. (3) The absorbent article according to (1) or (2) above, wherein the angle formed by the intersection of the two line segments constituting the X-shaped fused portion, facing the longitudinal end of the absorbent sheet, is an obtuse angle. (4) The X-shaped fused portions are arranged in multiples at intervals along the longitudinal direction of the absorbent sheet, and the absorbent article is one of the above (1) to (3). (5) Any of the absorbent articles described in (1) to (4) above, wherein the plan view shape of the region containing the superabsorbent polymer surrounded by the central fusion portion, the side fusion portions, and the X-shaped fusion portion is triangular or trapezoidal, and the triangles and trapezoids are alternately repeated in the longitudinal direction. (6) Any of the absorbent articles described in (1) to (5) above, further having connecting fused portions at one end and the other end in the longitudinal direction of the absorbent sheet, which connect the end of the central fused portion and the respective ends of the two side fused portions. (7) An absorbent article according to any of (1) to (6) above, wherein the central fusion portion, the fusion portions on both sides, and the X-shaped fusion portion are all ultrasonic fusion portions. [Effects of the Invention]

[0013] According to the present invention, there is provided a thin absorbent article that includes an absorbent sheet capable of fully exerting the body fluid absorption ability of highly absorbent polymer particles, enables multiple absorptions of body fluids, is less likely to leak, and has good fit.

Brief Description of the Drawings

[0014] [Figure 1] It is a plan view schematically showing the configuration of the absorbent article according to this embodiment. [Figure 2] It is a schematic cross-sectional view taken along the x-x cutting line shown in FIG. 1.

Mode for Carrying Out the Invention

[0015] In this specification, the wearing of an absorbent article refers to the state in which the absorbent article is worn on the body, regardless of before and after the absorption of body fluids. In an absorbent article, the longitudinal direction is the direction indicated by Y in the figure, which extends across the front and back of the body through the crotch of the wearer when the absorbent article is worn on the body. The width direction is the direction indicated by X in the figure, which is orthogonal to the longitudinal direction. The thickness direction is the direction indicated by Z in the figure, in which each component member is laminated. The skin side surface is the surface that contacts the skin of the wearer and the surface facing the skin when the absorbent article is worn. The non-skin side surface is the surface that contacts the clothing of the wearer or the surface facing the clothing. Body fluid refers to a liquid discharged from the body to the outside, such as urine, blood, and moisture in soft feces.

[0016] <Absorbent Article> Hereinafter, the absorbent article 50 according to this embodiment will be described with reference to the drawings. FIGS. 1 and 2 show the absorbent article 50. These drawings do not define the shape, dimensions, size relationship, etc. of each component member in the absorbent article 50.

[0017] The absorbent article 50 of this embodiment can be used as various absorbent articles for infants, adults, and the elderly. Examples include pad products such as light incontinence products, light incontinence liners, urine pads, and sanitary napkins, as well as diaper products such as pant-type diapers and tape-fastening diapers. Among these, it is particularly suitable for use as pad products such as light incontinence products and urine pads, taking advantage of its thinness and the fact that its absorption capacity and absorption rate do not decrease even after multiple absorptions. It is also possible to combine various diaper products as outer layers with the absorbent article 50 as an inner layer. The dimensions of the absorbent article 50 in the longitudinal direction (maximum dimension) and the dimensions in the width direction (maximum dimension) are not particularly limited, but are, for example, in the range of 100 mm to 600 mm and 50 mm to 250 mm, respectively. By adjusting the dimensions of the absorbent article 50 to the above range, various forms of absorbent articles can be easily obtained.

[0018] The absorbent article 50 shown in Figures 1 and 2 comprises a liquid-permeable top sheet 10 located on the skin side, a liquid-impermeable back sheet 30 positioned opposite the top sheet 10 and on the non-skin side, an absorbent sheet 20 positioned between the top sheet 10 and the back sheet 30, and a pair of three-dimensional gathers 40 provided on the skin side of the top sheet 10.

[0019] The absorbent sheet 20 comprises two hydrophilic nonwoven fabrics 15 and 16 and superabsorbent polymer particles 12 sandwiched between them. The two hydrophilic nonwoven fabrics 15 and 16 have a fusion portion that joins them together. The fusion portion includes a central fusion portion 21 that is continuous in the longitudinal direction along the center of the width of the absorbent sheet 20, two side fusion portions 22 that are continuous in the longitudinal direction along both sides of the width of the absorbent sheet 20, and an X-shaped fusion portion 23 that intersects the central fusion portion 21 and the side fusion portions 22 in the longitudinal direction and is X-shaped in plan view, spaced apart from each other. In this embodiment, the region where the superabsorbent polymer particles 12 are located, surrounded by the central fusion portion 21, the side fusion portions 22, and the X-shaped fusion portion 23, includes a region 25 where the superabsorbent polymer 12 has a trapezoidal shape in plan view (hereinafter also simply referred to as the "trapezoidal region 25") and a region 26 where the superabsorbent polymer particles 12 have a triangular shape in plan view (hereinafter also simply referred to as the "triangular region 26"). The trapezoidal region 25 and the triangular region 26 are alternately and repeatedly arranged in the longitudinal direction of the absorbent sheet 20 on both sides of the central fusion portion 21.

[0020] According to this embodiment, the absorbent sheet 20 has trapezoidal regions 25 and triangular regions 26 that are alternately and repeatedly arranged in the longitudinal direction of the absorbent sheet 20 on both sides of the central fusion portion 21, thereby suppressing the occurrence of uneven distribution of superabsorbent polymer particles 12. For example, if a triangular region 26 is placed in the central part in the longitudinal direction, trapezoidal regions 25 will be present on both sides in the longitudinal direction. With this arrangement, when the absorbent article 50 is worn, the thin absorbent sheet 20 deforms well to fit the contours of the wearer's body, and the internal space of the trapezoidal regions 25 and triangular regions 26 becomes narrower. As a result, gaps are less likely to form inside the trapezoidal regions 25 and triangular regions 26, and even if the absorbent article 50 is worn in a tilted position, uneven distribution of superabsorbent polymer particles 12 is significantly suppressed.

[0021] Furthermore, according to a preferred embodiment in which the fused portion is formed by ultrasonic fusion (ultrasonic sealing), the central fused portion 21 and the X-shaped fused portion 23 generate the following effects. First, in the central fused portion 21, even after the swelling of the superabsorbent polymer particles 12, the sonic seal area remains as a groove, and the bodily fluid absorbed from the top sheet 10 side flows into it, mainly suppressing a decrease in the absorption rate during multiple bodily fluid absorptions. Second, in the diagonally running sonic seal area, which is the X-shaped fused portion 23, when the trapezoidal existence area 25 and the triangular existence area 26 are inclined, the bodily fluid flows more easily not only in the longitudinal direction but also in the direction of inclination. Also, at this time, the superabsorbent polymer particles 12 around the diagonal sonic seal area swell and rise up like a levee, so after absorption, the flow to the edge of the absorbent article 50 can be delayed, and as a result, the bodily fluid is more easily absorbed before reaching the edge of the absorbent article 50, reducing leakage. Furthermore, without the angled sonic seal, bodily fluids would easily flow directly to the edge of the absorbent material 50, leading to leakage.

[0022] The absorbent article 50 of this embodiment is based on a top sheet 10, an absorbent sheet 20, and a back sheet 30 as its basic structural units. Various known modifications can be made as needed, such as the arrangement of a three-dimensional gather 40 as described above, or the arrangement of a liquid-permeable transfer sheet (not shown) or a liquid-permeable second sheet (not shown) between the top sheet 10 and the absorbent sheet 20. The components of the absorbent article 50 will be described in more detail below, in the order of the top sheet 10, absorbent sheet 20, back sheet 30, and three-dimensional gather 40.

[0023] <Top sheet> The top sheet 10 is a liquid-permeable sheet-like substrate that allows bodily fluids to pass rapidly towards the absorbent sheet 20. The top sheet 10 is preferably made of a soft, non-irritating substrate so that it can come into contact with the wearer's skin. Examples of such substrates include hydrophilic sheets, composite sheets which are laminates of the same or different types of hydrophilic sheets, open films such as open polyethylene films, and foamed films such as polyethylene foam and urethane foam. Examples of hydrophilic sheets include air-through nonwoven fabrics, thermal-bonded nonwoven fabrics, spunlace nonwoven fabrics, and spunbond nonwoven fabrics made using one or more types of synthetic fibers such as polypropylene and polyethylene, regenerated fibers such as rayon, and natural fibers such as cotton. Among these, nonwoven fabrics are preferred, and air-through nonwoven fabrics, thermal-bonded nonwoven fabrics, and spunbond nonwoven fabrics are more preferred.

[0024] The top sheet 10 may have embossing or perforation applied to its surface to improve liquid permeability. The top sheet 10 may contain one or more of the following to reduce skin irritation: lotion, antioxidant, anti-inflammatory component, pH adjuster, antibacterial agent, moisturizer, etc. The basis weight of the top sheet 10 should be, for example, 18 g / m², from the viewpoint of strength, processability, and liquid return rate. 2 More than 400g / m 2 The following range applies. The shape of the top sheet 10 is not particularly limited and should be such that it covers part or all of the absorbent sheet 20, as is necessary to guide the bodily fluids to the absorbent sheet 20 without leakage.

[0025] <Absorbent sheet> The absorbent sheet 20 has a longitudinal dimension (maximum length) that is, for example, in the range of 100 mm to 600 mm, 150 mm to 500 mm, or 270 mm to 500 mm. The width dimension (maximum width) of the absorbent sheet 20 is, for example, in the range of 50 mm to 250 mm, 60 mm to 200 mm, or 70 mm to 105 mm. Embossing may be applied to the entire surface or part of the absorbent sheet 20. Examples of planar shapes of the absorbent sheet 20 include hourglass shape, I-shape, rectangle, rounded quadrilateral with rounded corners, oval, etc.

[0026] As shown in Figures 1 and 2, the absorbent sheet 20 of this embodiment comprises two hydrophilic sheets 15 and 16, superabsorbent polymer particles 12 sandwiched between them, and a fusion portion that partially joins the two hydrophilic sheets 15 and 16. The fusion portion comprises a central fusion portion 21 that is continuous in the longitudinal direction along the center of the width of the absorbent sheet 20, two side fusion portions 22 that are continuous in the longitudinal direction along both sides of the width of the absorbent sheet 20, an X-shaped fusion portion 23 that intersects the central fusion portion 21 and the side fusion portions 22 in the longitudinal direction and is X-shaped in plan view, and connecting fusion portions 24a and 24b that connect the end of the central fusion portion 21 and the respective ends of the side fusion portions 22 at one end and the other end of the absorbent sheet 20 in the longitudinal direction.

[0027] (Hydrophilic sheet) As the hydrophilic sheets 15 and 16, any of those commonly used in this field can be used, such as hydrophilic nonwoven fabrics such as thermal bond nonwoven fabric, spunbond nonwoven fabric, airlaid nonwoven fabric, air-through nonwoven fabric, and pulp-containing nonwoven fabric, as well as tissue paper and absorbent paper. Among the hydrophilic sheets, hydrophilic nonwoven fabrics are preferred, thermal bond nonwoven fabric, spunbond nonwoven fabric, air-through nonwoven fabric, and pulp-containing nonwoven fabric are more preferred, and air-through nonwoven fabric, pulp-containing nonwoven fabric, and spunbond nonwoven fabric are even more preferred. The thickness of the hydrophilic sheets 15 and 16 is, for example, in the range of 0.10 mm to 2.50 mm, and the basis weight is, for example, 5 g / m². 2 More than 40g / m 2The range is as follows. Note that hydrophilic sheets 15 and 16 can be of the same type or different types.

[0028] (Highly absorbent polymer particles) The superabsorbent polymer particles (hereinafter also referred to as "SAP") 12 are not particularly limited as long as they can absorb body fluids and prevent backflow, and examples include polyacrylates, polyaspartates, (starch-acrylic acid) graft copolymers, (acrylic acid-vinyl alcohol) copolymers, (isobutylene-maleic anhydride) copolymers, and their saponified products. Among these, polyacrylates are preferred from the viewpoint of absorption per unit weight, alkali metal polyacrylates are more preferred, and sodium polyacrylate is even more preferred. The superabsorbent polymer 12 can be used alone or in combination of two or more types.

[0029] By using superabsorbent polymer particles 12 having a medium particle size, the basic performance related to absorption can be enhanced, and the rough texture caused by the hardening of the absorbent sheet 20 can be reduced. The medium particle size of the superabsorbent polymer particles 12 is, for example, in the range of 50 μm to 600 μm or 100 μm to 500 μm.

[0030] (fused part) The fused portion partially joins the hydrophilic sheets 15 and 16, forming a trapezoidal region 25 and a triangular region 26 within the absorbent sheet 20, which are areas where highly absorbent polymer particles 12 exist, surrounded by the hydrophilic sheets 15 and 16 and the fused portion. As described above, the fused portion of this embodiment has a central fused portion 21, side fused portions 22, an X-shaped fused portion 23, and connecting fused portions 24a and 24b.

[0031] (Central fusion part) The central fusion portion 21 is formed to extend linearly from one end to the other in the longitudinal direction through the center of the width direction of the absorbent sheet 20. The width of the central fusion portion 21 is not particularly limited, but for example, it is in the range of 0.5 mm to 13 mm. If the width of the central fusion portion 21 is less than 0.5 mm, the bonding strength of the hydrophilic sheets 15 and 16 becomes weaker, and the joint tends to come loose more easily. If the width of the central fusion portion 21 exceeds 13 mm, the amount of superabsorbent polymer particles 12 that can be contained in the internal space of the trapezoidal region 25 and the triangular region 26 decreases, and the absorbent article 50 tends to have inferior body fluid absorption capacity. In addition, the rigidity of the absorbent sheet 20 becomes unnecessarily high, and the fit of the absorbent sheet 20 to the body tends to decrease.

[0032] (Both sides fused together) The two side-by-side fused portions 22 are formed on both sides of the absorbent sheet 20 in the width direction, extending almost linearly from one end to the other in the longitudinal direction, with one portion at each end. The two side-by-side fused portions 22 are located symmetrically in the width direction with respect to the central fused portion 21 as the axis of symmetry. Furthermore, the side-by-side fused portions 22 are formed with a gap between them from both ends of the absorbent sheet 20 in the width direction, thereby maintaining the flexibility that is an advantage of the absorbent sheet 20 as a thin sheet, and preventing a decrease in fit. The width of the side-by-side fused portions 22 is not particularly limited, but for example, it is in the range of 0.5 mm to 4 mm. If the width of the side-by-side fused portions 22 is less than 0.5 mm, the bonding strength of the hydrophilic sheets 15 and 16 becomes weaker, and the joint tends to come undone easily during wear, etc. If the width of the fused portions 22 on both sides exceeds 4 mm, the amount of superabsorbent polymer particles 12 that can be contained in the internal space of the trapezoidal region 25 and the triangular region 26 decreases, and the absorbent article 50 tends to have inferior body fluid absorption capacity.

[0033] (X-shaped fused part) The X-shaped fusion portion 23 is a fusion portion having an X-shape in plan view, formed by the intersection of line segments 23a and 23b. In a preferred embodiment, the intersection of line segments 23a and 23b lies on the central fusion portion 21 (in other words, the central fusion portion 21 and the X-shaped fusion portion 23 intersect only at the center of the width direction of the central fusion portion 21), and both ends of line segments 23a and 23b are in contact with the side fusion portions 22. Furthermore, of the angles formed by the intersection of line segments 23a and 23b, the angle α facing the width direction end of the absorbent sheet 20 is an acute angle, and the angle β facing the longitudinal direction end of the absorbent sheet 20 is an obtuse angle. With this configuration, multiple X-shaped fusion portions 23 are arranged at predetermined intervals in the longitudinal direction. By arranging multiple X-shaped fusion portions 23 in the longitudinal direction, trapezoidal existence regions 25 and triangular existence regions 26 are alternately formed in the longitudinal direction on both sides of the width direction of the central fusion portion 21, thereby obtaining the effects unique to this embodiment described above.

[0034] The widths of the line segments 23a and 23b constituting the X-shaped fused portion 23 are not particularly limited, but are, for example, in the range of 0.5 mm to 4 mm. If the width of the line segments 23a and 23b is less than 0.5 mm, the bonding strength of the hydrophilic sheets 15 and 16 will be weaker, and the joints will tend to come apart easily during wear, etc. If the width of the line segments 23a and 23b exceeds 4 mm, the amount of superabsorbent polymer particles 12 that can be contained in the internal space of the trapezoidal region 25 and the triangular region 26 will decrease, and the absorbent article 50 will tend to have inferior body fluid absorption capacity.

[0035] (Connection fusion part) The connecting fusion sections 24a and 24b are positioned facing each other substantially parallel to one end and the other end in the longitudinal direction of the absorbent sheet 20, connecting the end of the central fusion section 21 to each end of the side fusion sections 22, and further connecting the ends of the X-shaped fusion section 23. The connecting fusion sections 24a and 24b are provided as needed, and by providing them, the uneven rigidity of the absorbent sheet 20 caused by the formation of the central fusion section 21, the side fusion sections 22, and the X-shaped fusion section 23 can be corrected, the rigidity of the entire absorbent sheet 20 can be made uniform, and the feel against the skin and fit to the body surface can be improved. Furthermore, by forming the connecting fusion sections 24a and 24b at predetermined intervals from the longitudinal end of the absorbent sheet 20, it becomes easier to connect them to the ends of the central fusion section 21, the side fusion sections 22, and the X-shaped fusion section 23, resulting in a more uniform absorbent sheet 20 and effectively preventing a decrease in fit and other properties.

[0036] <Method for manufacturing absorbent sheets> The absorbent sheet 20 of this embodiment can be manufactured by a manufacturing method that includes, for example, the steps of: scattering superabsorbent polymer particles 12 in a predetermined pattern on the skin side of a hydrophilic sheet 16, which is placed on the non-skin side, leaving an area where a fusion portion is to be formed; overlapping the non-skin side of a hydrophilic sheet 15 onto the skin side of the hydrophilic sheet 16 to obtain a laminate; and forming a fusion portion while applying pressure and / or heating the obtained laminate as needed. The fusion portion can be formed, for example, using a hot melt adhesive, or by welding methods such as heat sealing or ultrasonic sealing (ultrasonic welding). As mentioned above, ultrasonic sealing is preferred as the welding method.

[0037] <Back seat> The backsheet 30 can be formed using a breathable or non-breathable base material that is impermeable to liquids so that the bodily fluids held by the absorbent sheet 20 do not wet the clothing. Examples of such base materials include resin films and composite sheets which are laminates of resin films and nonwoven fabrics. The nonwoven fabric used in the composite sheet is not particularly limited in its manufacturing method and can include single-layer nonwoven fabrics such as spunbond nonwoven fabrics and meltblown nonwoven fabrics, composite nonwoven fabrics such as spunbond nonwoven fabric / meltblown nonwoven fabric laminates and spunbond nonwoven fabric / meltblown nonwoven fabric / spunbond nonwoven fabric laminates, and composite materials thereof. Examples of resin films include polyester, polyvinyl alcohol, polyethylene, polypropylene, and composite films of polyethylene and polypropylene.

[0038] The basis weight of backsheet 30 is, for example, 15 g / m², considering strength and processability. 2 More than 40g / m 2 The following range applies. Furthermore, to prevent stuffiness during wear, it is preferable that the back sheet 30 be breathable. To provide breathability to the back sheet 30, for example, a filler can be compounded into the resin film of the base material, or the back sheet 30 can be embossed. Calcium carbonate can be used as a filler, and the compounding method can be any known method without limitation.

[0039] <3D Gathering> The three-dimensional gathers 40 are fixed to the skin-facing side of the top sheet 10 along the longitudinal direction of the absorbent article 50 near both ends in the width direction of the absorbent article 50, for example, to prevent lateral leakage of bodily fluids excreted by the wearer of the absorbent article 50. The three-dimensional gathers 40 include an elastic stretchable member 40a and a water-repellent and / or waterproof sheet member 40b.

[0040] The elastic stretchable member 40a is arranged along the longitudinal direction near the free end (other end) of the sheet member 40b, providing the free end with uprightness and allowing the free end and its vicinity to deform to conform to the wearer's body shape. In this embodiment, one end (fixed end) of the sheet member 40b in the width direction is fixed near both ends in the width direction of the skin-facing side of the back sheet 30, a portion in the width direction is fixed near both ends in the width direction of the skin-facing side of the top sheet 10, and the other end in the width direction is an upright free end. The fixing position of the fixed end (one end in the width direction) of the sheet member 40b is not limited to this embodiment, and examples include the non-skin-facing side of the back sheet 30, near both ends in the width direction of the skin-facing or non-skin-facing side of the joint between all or part of the edges of the top sheet 10 containing the absorbent sheet 20 and the back sheet 30, and near both ends in the width direction of the skin-facing side of the top sheet 10.

[0041] The sheet member 40b is a water-repellent and / or waterproof sheet, and is made of, for example, a nonwoven fabric. The nonwoven fabric for the first sheet member can be any water-repellent and / or waterproof (liquid-impermeable) nonwoven fabric formed from hydrophobic fibers, without any particular limitations. Examples include spunbond nonwoven fabric, meltblown nonwoven fabric, and composite nonwoven fabric (SMS nonwoven fabric) which is a laminate of spunbond nonwoven fabric / meltblown nonwoven fabric / spunbond nonwoven fabric. The basis weight of the sheet member 40b is, for example, 13 g / m². 2 More than 20g / m 2 The range is as follows. As the elastic stretchable member 40a, thread-like, string-like, or strip-like materials made of natural rubber, synthetic rubber, polyurethane, etc., can be used as appropriate.

[0042] <Method for manufacturing absorbent articles> The absorbent article 50 can be manufactured by known manufacturing methods, for example, a manufacturing method that includes the steps of: placing an absorbent sheet 20 between a top sheet 10 and a back sheet 30; fixing the top sheet 10 and the back sheet 30 together using a hot melt adhesive, heat embossing, ultrasonic embossing, high-frequency embossing, etc., around part or all of their circumferences; and installing three-dimensional gathers 40 at predetermined positions on the back sheet 30 and the top sheet 10. If the absorbent article 50 is a urine pad or a light incontinence pad, it can be individually packaged in a packaging body and then folded into thirds in the longitudinal direction. Leg gathers, waist gathers, side flaps, etc., can also be provided as needed.

[0043] Although the present invention has been described above using embodiments, it goes without saying that the technical scope of the present invention is not limited to the scope described in the above embodiments and examples. It will be obvious to those skilled in the art that various modifications or improvements can be made to the above embodiments. Furthermore, it is clear from the claims that such modified or improved forms may also be included in the technical scope of the present invention. [Explanation of Symbols]

[0044] 10 Top Sheets 15, 16 Hydrophilic sheet 20 absorbent sheets 21 Center fusion part 22 Fused joint on both sides 23 X-shaped fused part 24a, 24b Connection fusion part 30 Backseat 40 Three-dimensional gathers 40a Elastic stretchable member 40b Sheet material 50 Absorbent articles

Claims

1. An absorbent article comprising a liquid-permeable top sheet, a liquid-impermeable back sheet, and an absorbent sheet disposed between them, The absorbent sheet comprises two hydrophilic sheets and a superabsorbent polymer sandwiched between them. The two hydrophilic sheets have a fused portion formed by ultrasonic fusion that joins them together. The fused portion is, The central fused portion of the absorbent sheet is continuous in the longitudinal direction, The absorbent sheet has two fused portions on both sides in the width direction that are continuous in the longitudinal direction, It has an X-shaped fusion portion that intersects the central fusion portion and the two side fusion portions in the longitudinal direction, and is X-shaped in plan view, The planar shape of the region containing the superabsorbent polymer, surrounded by the central fusion portion, the side fusion portions, and the X-shaped fusion portion, is triangular or trapezoidal. The aforementioned triangle and the aforementioned trapezoid are alternately repeated in the longitudinal direction. An absorbent article characterized by the following features.

2. The absorbent article according to claim 1, wherein the fused portion is linear and in the shape of a solid line.

3. The absorbent article according to claim 1 or claim 2, wherein the central fusion portion and the X-shaped fusion portion intersect only at the center in the width direction of the central fusion portion.

4. The absorbent article according to any one of claims 1 to 3, wherein the angle formed by the intersection of the two line segments constituting the X-shaped fused portion, facing the longitudinal end of the absorbent sheet, is an obtuse angle.

5. The absorbent article according to any one of claims 1 to 4, wherein the X-shaped fused portions are arranged in a plurality at intervals in the longitudinal direction of the absorbent sheet.

6. The absorbent article according to any one of claims 1 to 5, further comprising connecting fused portions at one end and the other end in the longitudinal direction of the absorbent sheet, which connect the end of the central fused portion and the respective ends of the fused portions on both sides.

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