Absorbent article

Abstract

The grit feel of the highly absorbent polymer particles is difficult to transmit. The problem is solved by an absorbent article provided with an absorbent member (50) having an absorbent body (56) and a packaging nonwoven fabric (58) that encloses the absorbent body (56), the absorbent body (56) having a layer in which pulp fibers and highly absorbent polymer particles are mixed and accumulated, and the absorbent member (50) being provided with a plurality of layers in which the pulp fibers and the highly absorbent polymer particles are mixed and accumulated. Grooves (53), which are recessed from the front surface of the absorbent member (50) into the absorbent body (56) and have bottom portions (51) compressed in the thickness direction, are continuous in a lattice shape, and each groove (53) has intersecting portions (21) and non-intersecting portions (22) located between adjacent intersecting portions (21). The thickness of the bottom section (51) increases stepwise or continuously from the center of the non-intersecting section (22) in the longitudinal direction toward the intersecting section (21).

Description

Technical Field

[0001] The present invention relates to absorbent articles such as disposable diapers. Background Art

[0002] In absorbent articles, an absorbent body formed by mixing and accumulating pulp fibers and superabsorbent polymer particles is generally used. In order to improve the shape retention during and after manufacturing, such an absorbent body is generally built-in as an absorbent member formed by wrapping a packaging sheet made of crepe paper or the like (for example, refer to patent documents 1 and 2).

[0003] When the absorbent member of an absorbent article is sandwiched between the legs, it is subjected to forces in various directions from both sides in the width direction due to the movement of the legs such as walking, so it is required to have good fit in the crotch area, and on the other hand, it is also required to have shape retention to prevent the shape deformation such as wrinkles or tears of the absorbent body. Of course, in the absorbent member of a disposable diaper, it is also required to ensure the absorption performance of the crotch area.

[0004] As a method for improving the shape retention of the absorbent body, a method of providing grooves in a grid pattern or the like is known, wherein the grooves have a bottom formed by compressing the absorbent member in the thickness direction by embossing or the like (see, for example, Patent Documents 1 and 2). However, if the packaging sheet wrapping the absorbent body is crepe paper, when forming the compressed portion, the crepe paper may be broken at the edge of the compressed portion or between adjacent compressed portions. In addition, the crepe paper is easily broken due to reduced strength in a wet state after absorbing excrement. If the packaging sheet is broken, the superabsorbent polymer particles may fall out from there and be exposed on the surface of the absorbent article, which is not preferred.

[0005] As a packaging sheet, it is also known to use a nonwoven fabric with a fine mesh (hereinafter referred to as a packaging nonwoven fabric). However, when a packaging nonwoven fabric is used, there is a problem that if the bottom of the groove formed on the front surface of the absorbent member is traced with a finger, a gritty touch of the superabsorbent polymer particles is generated. If the user feels this gritty touch, it may deteriorate the wearing feeling or reduce the product image, so it is not preferred.

[0006] Prior art literature

[0007] Patent Literature

[0008] Patent Document 1: Japanese Patent Application Publication No. 2021-000236

[0009] Patent Document 2: Japanese Patent No. 6380454 Summary of the invention

[0010] Problems to be solved by the invention

[0011] Therefore, a main problem of the present invention is to make it difficult for the gritty touch of superabsorbent polymer particles to be transmitted to the user when using a packaging nonwoven fabric.

[0012] Means for solving problems

[0013] The absorbent article that has solved the above-mentioned problems is as follows.

[0014] <Method 1>

[0015] An absorbent article, characterized in that

[0016] The absorbent article comprises a crotch portion, and a front side portion and a rear side portion extending from the crotch portion toward the front side and the rear side, respectively.

[0017] The absorbent article includes an absorbent member having an absorbent body provided at a position including the crotch portion, and a wrapping nonwoven fabric wrapping the absorbent body.

[0018] The absorbent body has a layer in which pulp fibers and superabsorbent polymer particles are mixed and accumulated.

[0019] In the absorbent member, grooves which are recessed from the front surface of the absorbent member into the absorbent body and have bottoms compressed in the thickness direction are continuous in a lattice shape, and,

[0020] The groove has an intersection portion and a non-intersection portion located between adjacent intersection portions, and in at least a portion of the front surface of the absorbent member, the thickness of the bottom portion gradually or continuously thickens as it moves from the center of the non-intersection portion in the length direction toward the intersection portion.

[0021] (Effect)

[0022] In the case of using a wrapping nonwoven fabric, if a groove having a bottom compressed in the thickness direction is formed on the front surface of the absorbent member, the wrapping nonwoven fabric and the absorbent body are compressed in the thickness direction at the bottom of the groove, resulting in a relatively increased amount of superabsorbent polymer particles on the front surface of the absorbent body and in the vicinity thereof, and the superabsorbent polymer particles are held in a state of being difficult to move on the front surface of the hardened absorbent body and in the vicinity thereof due to the reduction and densification of the cushioning properties of the wrapping nonwoven fabric and the absorbent body in the thickness direction, and are covered by the thinned wrapping nonwoven fabric. Therefore, when the bottom of the groove is traced with a finger, a gritty touch of the superabsorbent polymer particles is produced.

[0023] The superabsorbent polymer particles that are a problem here are located at the bottom of the grooves, which are far from the skin, that is, the part that is difficult for the user to contact directly or indirectly through other sheets, so the touch of the superabsorbent polymer particles is basically difficult to convey to the user. However, if the grooves are formed in a lattice shape, the packaging nonwoven fabric is stretched in two directions at the corners facing the intersections of the bottom of the grooves, and the thickness of the corners becomes particularly thin, resulting in that the intersections of the bottom of the grooves are more likely to come into direct or indirect contact with the skin than the non-intersections.

[0024] In contrast, in the absorbent article, (a) the thickness of the bottom portion is gradually or continuously thickened as it approaches the intersection portion from the center of the length direction of the non-intersection portion (i.e., as it approaches the intersection portion from the center of the length direction of the non-intersection portion, the degree of compression of the bottom portion is weakened and the density of the bottom portion is reduced), thereby suppressing the reduction in thickness of the corner portion facing the intersection portion of the bottom portion of the groove, and the intersection portion of the bottom portion of the groove is difficult to contact the user's skin. Therefore, compared with the case where the thickness of the bottom portion of the groove is approximately constant, the gritty touch of the superabsorbent polymer particles is difficult to be transmitted to the user. Furthermore, (b) at the intersection portion of the bottom portion of the groove, which is more likely to contact the user's skin, the increase in the amount of superabsorbent polymer particles on the front side of the absorbent and its vicinity is suppressed, and the reduction and densification of the cushioning properties of the packaging nonwoven fabric and the absorbent in the thickness direction are also suppressed. Therefore, even if the intersection portion of the bottom portion of the groove contacts the user's skin, the gritty touch of the superabsorbent polymer particles is weak, and therefore, the gritty touch of the superabsorbent polymer particles is more difficult to be transmitted to the user.

[0025] Furthermore, since the grooves which are recessed from the front surface of the absorbent member into the absorbent body and have bottoms compressed in the thickness direction are continuous in a lattice shape, liquid diffusibility and shape retention of the absorbent body are also ensured.

[0026] <Method 2>

[0027] The absorbent article according to the first aspect, wherein:

[0028] The weight per unit area of ​​the pulp fibers in the absorbent is 100 g / m 2 ~450g / m 2 ,

[0029] The weight ratio of pulp fibers to superabsorbent polymer particles in the absorbent is 30:70 to 70:30.

[0030] The maximum thickness of the absorption member is 4 mm to 35 mm.

[0031] The thickness of the bottom portion at the center of the non-intersecting portion in the longitudinal direction is 15% to 35% of the maximum thickness of the absorbing member.

[0032] The thickness of the bottom portion at the intersection portion is 1.4 to 6 times the thickness of the bottom portion at the center in the longitudinal direction of the non-intersection portion.

[0033] (Effect)

[0034] The material composition of the absorbent body and the degree of compression of the bottom of the groove can be appropriately determined, but are preferably within the range of the present embodiment.

[0035] <Method 3>

[0036] An absorbent article according to a second aspect, wherein:

[0037] The width of the bottom is 1 mm to 3 mm,

[0038] The groove is formed in an oblique lattice shape consisting of a first portion and a second portion, wherein the first portion is inclined 40° to 50° clockwise relative to the front-rear direction in a plan view, and the second portion is inclined 40° to 50° counterclockwise relative to the front-rear direction in a plan view.

[0039] (Effect)

[0040] The size and shape of the grooves can be appropriately determined, but if they are formed in an oblique lattice shape as in this embodiment, the shape retention and softness of the absorbent body are excellent, and the liquid diffusibility is also excellent, so it is preferred. However, if the grooves are formed in the pattern of this embodiment, the thickness reduction of the corners facing the intersection of the bottom of the grooves only needs to be small, so it is preferred.

[0041] <Method 4>

[0042] The absorbent article according to any one of the first to third aspects, wherein:

[0043] The packaging nonwoven fabric comprises one or more meltblown layers and one or more protective layers.

[0044] The unit area weight of the packaging nonwoven fabric is 10 g / m 2 ~17g / m 2 ,

[0045] The protective layer is made of fibers with an average fiber diameter of 10 μm to 25 μm.

[0046] The constituent fibers of the meltblown layer are fibers having an average fiber diameter of 5 μm or less.

[0047] The air permeability of the packaging nonwoven fabric was 25.5 cm when the A method (Frazier method) was measured in accordance with JIS L 1096:2010 in a state where five sheets of the packaging nonwoven fabric were stacked. 3 / cm2 ·s~70.0cm 3 / cm 2 ·s,

[0048] The packaging nonwoven fabric has an elongation of 20% to 100% in the front-to-back direction according to the standard specified in JIS L 1913:2010,

[0049] The packaging nonwoven fabric has an elongation in the width direction of 20% to 110% according to the standard specified in JIS L 1913:2010.

[0050] (Effect)

[0051] If the packaging nonwoven fabric is not easy to stretch, it is not only difficult to form a firm groove, but also the softness of the absorbent member will be reduced. In addition, if the fiber structure of the packaging nonwoven fabric is sparse, the superabsorbent polymer particles are easy to escape. Therefore, with respect to the packaging nonwoven fabric, it is preferred to use a nonwoven fabric that is sufficiently thin and easy to stretch and has a dense meltblown layer as in this embodiment. When such a packaging nonwoven fabric is used to form the same groove, the gritty touch of the superabsorbent polymer particles is easily transmitted to the user, but by having the above-mentioned (a) and (b) features, it is possible to achieve the improvement of the shape retention and softness of the absorbent while suppressing the gritty touch of the superabsorbent polymer particles from being transmitted to the user.

[0052] In addition, air permeability is also an indicator of the ease with which superabsorbent polymer particles can escape.

[0053] <Method 5>

[0054] The absorbent article according to the fourth aspect, wherein:

[0055] The unit area weight of the packaging nonwoven fabric is 15 g / m 2 ~17g / m 2 .

[0056] (Effect)

[0057] If the packaging nonwoven fabric is not easily stretched, it is not only difficult to form a firm groove, but also the flexibility of the absorbent member is reduced. In addition, if the fiber structure of the packaging nonwoven fabric is sparse, the superabsorbent polymer particles are easy to escape. Therefore, as for the packaging nonwoven fabric, it is preferred to use a nonwoven fabric that is sufficiently thin and easy to stretch and has a dense meltblown layer as in this embodiment. These aspects are as described above.

[0058] However, if grooves with a compressed portion compressed in the thickness direction as the bottom are formed in a grid-like manner on the front side of the absorbent member in order to improve the shape retention of the absorbent body and the liquid diffusibility of the absorbent member in the front-back direction and the width direction, when the surface of the packaging nonwoven fabric is subjected to friction at the intersection of the grooves and its vicinity, the superabsorbent polymer particles may sometimes fall out. One of the main reasons for this is that the packaging nonwoven fabric is stretched in two directions (the direction of intersection with an adjacent groove and the direction of intersection with another groove) at the intersection and its vicinity, and the thickness becomes thinner and the fiber gap becomes larger than other parts. In addition, at the bottom of the groove and its vicinity, the absorbent body is compressed in the thickness direction, resulting in a relatively increased amount of superabsorbent polymer particles on the surface and its vicinity (i.e., the amount of superabsorbent polymer particles that can fall out of the absorbent body) is also considered to be one of the main reasons.

[0059] In contrast, if the packaging nonwoven fabric of this method is used, and the thickness of the bottom is gradually or continuously thickened as it moves from the center of the length direction of the non-intersection part to the intersection part (that is, the compression of the bottom is weakened and the density of the bottom is reduced as it moves from the center of the length direction of the non-intersection part to the intersection part), then compared with the case where this is not the case, the elongation of the packaging nonwoven fabric at both sides of the groove and the expansion of the fiber gap and the reduction of the thickness caused by this can be suppressed as it moves from the center of the length direction of the non-intersection part to the intersection part. Therefore, if a dense packaging nonwoven fabric having a unit area weight of more than a certain degree is combined with the aforementioned change in the thickness of the bottom as in this method, it is difficult for the superabsorbent polymer particles contained in the absorbent body to pass through the packaging nonwoven fabric even at the intersection part of the groove and its vicinity.

[0060] <Method 6>

[0061] The absorbent article according to any one of the first to fifth aspects, wherein:

[0062] The absorbent body has a cover layer composed of only accumulated pulp fibers covering the front side of the absorbent body.

[0063] (Effect)

[0064] The covering layer according to this embodiment is preferred because it is difficult for the superabsorbent polymer particles to fall out from the surface of the absorbent body.

[0065] <Method 7>

[0066] The absorbent article according to any one of the first to sixth aspects, wherein:

[0067] The packaging nonwoven fabric comprises: a back portion, which is located on the back side of the absorbent body; a first front side portion, which is a portion continuous with the back portion, bypassing one side edge of the absorbent body to reach the front side of the absorbent body; and a second front side portion, which is a portion continuous with the back portion, bypassing the other side edge of the absorbent body to reach the front side of the absorbent body,

[0068] The first front side portion and the second front side portion have a stacked portion that overlaps each other.

[0069] All of the grooves are formed in the laminated portion.

[0070] (Effect)

[0071] According to this aspect, it is also possible to suppress the superabsorbent polymer particles from coming out from the surface of the absorbent member.

[0072] <Method 8>

[0073] The absorbent article according to any one of the fifth to seventh aspects, wherein:

[0074] The middle portion of the absorbent member except for both ends in the width direction is not covered by other members throughout the entire front-back direction, and the wrapping nonwoven fabric is exposed on the front side of the absorbent article.

[0075] (Effect)

[0076] As described above, since the superabsorbent polymer particles can be prevented from escaping through the wrapping nonwoven fabric, components such as the top sheet covering the front surface of the absorbent member provided in conventional absorbent articles can be omitted, and in this case, significant cost reduction can be achieved.

[0077] Effects of the Invention

[0078] According to the present invention, there are advantages such as that, when the packaging nonwoven fabric is used, the gritty touch of the superabsorbent polymer particles is difficult to be conveyed to the user. BRIEF DESCRIPTION OF THE DRAWINGS

[0079] Figure 1 It is a top view showing the inner surface of the pants-type disposable diaper in the unfolded state.

[0080] Figure 2 It is a top view showing the outer surface of the pants-type disposable diaper in the unfolded state.

[0081] Figure 3 yes Figure 1 2-2 cross-sectional view.

[0082] Figure 4 yes Figure 1 Sectional view 3-3.

[0083] Figure 5 (a) is Figure 1 4-4 sectional view, (b) is Figure 1 Sectional view 5-5.

[0084] Figure 6 It is a perspective view of a pants type disposable diaper.

[0085] Figure 7 This is a plan view showing the outer surface of the inner body in the unfolded state together with the outline of the outer body.

[0086] Figure 8 This is a plan view showing the front surface of the absorbent body together with the outline of the packaging sheet.

[0087] Fig. 9 is a cross-sectional view of the absorbing member.

[0088] Fig.10 is a top view of the absorbing member.

[0089] Fig.11 This is an enlarged view of the main part of the front side of the absorbing member.

[0090] Fig.12 (a) is Fig.11 7-7 sectional view, (b) to (d) are Fig.11 Section 7-7 is an equivalent cross-sectional view.

[0091] Fig.13 This is a cross-sectional view showing the absorbent member in a state before the absorbent body is packaged with a packaging sheet.

[0092] Fig.14 This is a cross-sectional view showing the absorbent member in a state after the absorbent body is packaged with the packaging sheet and before the grooves are formed.

[0093] Fig.15 is a cross-sectional view of another absorbent member.

[0094] Fig.16 is a top view of another absorbent member.

[0095] Fig.17 is with Figure 1 The cross-sectional view of 2-2 is equivalent to another example.

[0096] Fig.18 is with Figure 1 Section 3-3 is a cross-sectional view of another example.

[0097] Fig.19 is a cross-sectional view of another absorbent member.

[0098] Fig. 20 It is a plan view showing another example of the absorbent body.

[0099] Fig.21 It is a schematic diagram showing a method for manufacturing an absorbing member.

[0100] Fig. 22 It is a perspective view of the protrusion of the backup roller.

[0101] Fig.23 This is a schematic diagram of the test device.

[0102] Fig.24 It is an explanatory diagram showing only the main part of the friction pattern. DETAILED DESCRIPTION

[0103] Hereinafter, as an example of a disposable diaper, a shorts-type disposable diaper will be described in detail with reference to the accompanying drawings. With respect to each component adjacent in the thickness direction, in addition to the fixing or joining parts described below, they are also fixed or joined in the same manner as known diapers as needed. The dotted part in the cross-sectional view represents an adhesive such as a hot melt adhesive as the fixing or joining means. The hot melt adhesive can be applied by known methods such as slit coating, continuous linear or dotted line droplet coating, spiral, Z-shaped, wavy spraying, or pattern coating (transfer of hot melt adhesive in relief mode). At the fixed part of the elastic component, the hot melt adhesive can be applied to the outer peripheral surface of the elastic component instead of these methods or together with these methods, and the elastic component can be fixed to the adjacent component. As a hot melt adhesive, for example, there are adhesives of the types such as EVA, adhesive rubber (elastic system), polyolefin, polyester polyamide, etc., which can be used without special limitation. As a means of fixing or joining the components together, a means based on material welding, such as heat sealing or ultrasonic sealing, may also be used. In the portion where liquid permeability in the thickness direction is required, the components adjacent in the thickness direction are fixed or joined in an intermittent pattern. For example, in the case of such intermittent fixing or joining using a hot melt adhesive, it is possible to appropriately apply an intermittent pattern such as a spiral, Z-shaped, or wavy pattern. In the case of applying to a range greater than the coating width based on one nozzle, it is possible to apply an intermittent pattern such as a spiral, Z-shaped, or wavy pattern with or without intervals in the width direction. As a means of joining the components together, a means based on material welding, such as heat sealing or ultrasonic sealing, may also be used.

[0104] In addition, as the nonwoven fabric in the following description, known nonwoven fabrics can be appropriately used according to the location or purpose. As the constituent fibers of the nonwoven fabric, in addition to synthetic fibers such as polyethylene or polypropylene, polyester, polyamide, etc. (in addition to single-component fibers, composite fibers of structures such as core-sheath, etc.), regenerated fibers such as rayon or cuprammonia fibers, natural fibers such as cotton, etc. can be selected without special restrictions, and they can also be mixed and used. In order to improve the softness of the nonwoven fabric, it is preferred that the constituent fibers are curled fibers. In addition, the constituent fibers of the nonwoven fabric can be either hydrophilic fibers (including fibers that are hydrophilic with the help of a hydrophilic agent), or hydrophobic fibers or water-repellent fibers (including fibers that are water-repellent with the help of a water-repellent agent). In addition, nonwoven fabrics are generally classified into short-fiber nonwoven fabrics, long-fiber nonwoven fabrics, spunbond nonwoven fabrics, meltblown nonwoven fabrics, spunlace nonwoven fabrics, hot-rolled (hot air) nonwoven fabrics, needle-punched nonwoven fabrics, point-bonded nonwoven fabrics, laminated nonwoven fabrics (including SMS nonwoven fabrics and SMMS nonwoven fabrics in which a meltblown layer is sandwiched between spunbond layers), etc., according to the fiber length, sheet forming method, fiber bonding method, and laminated structure, but any of them can be used.

[0105] Figure 1 to Figure 6 An example of a shorts-type disposable diaper is shown. The shorts-type disposable diaper comprises: a rectangular front outer body 12F constituting the waistline portion on the front side, and a rectangular rear outer body 12B constituting the waistline portion on the rear side; and an inner body 200, which is arranged on the inner side of the outer bodies 12F and 12B in a manner extending from the front outer body 12F to the rear outer body 12B via the crotch portion M. The two side portions of the front outer body 12F and the two side portions of the rear outer body 12B are joined to form a side sealing portion 12A, whereby the opening formed by the front and rear ends of the outer bodies 12F and 12B becomes a waist opening WO for the wearer's waist to pass through, and the portions surrounded by the lower edges of the outer bodies 12F and 12B and the side edges of the inner body 200 on both sides in the width direction of the inner body 200 become leg openings LO for the legs to pass through. The inner body 200 is a part that absorbs and retains excreta such as urine, and the outer bodies 12F and 12B are parts for supporting the inner body 200 relative to the body of the wearer. In addition, the symbol Y represents the full length of the diaper in the unfolded state (the length in the front-to-back direction from the edge of the waist opening WO of the front body part F to the edge of the waist opening WO of the back body part B) when the front outer body 12F and the rear outer body 12B are not joined at the side seal part 12A, and the symbol X represents the full width of the diaper in the unfolded state.

[0106] The present shorts-type disposable diaper has a waist region T and a middle region L, wherein the waist region T is defined as the front-to-back range having the side seals 12A (the front-to-back range from the waist opening WO to the upper end of the leg openings LO), and the middle region L is defined as the front-to-back range of the portion forming the leg openings LO (between the front-to-back region having the side seals 12A of the front body portion F and the front-to-back region having the side seals 12A of the back body portion B). The portion of the front outer body 12F and the back outer body 12B located in the waist region T, i.e., the front waist region and the back waist region can be conceptually divided into a "waist" W forming the edge of the waist opening and a "waist lower portion" U which is a portion below it. Usually, when there is a boundary in the waistline portion on the front side and the waistline portion on the back side where the elastic stress in the width direction WD changes (for example, the thickness or elongation of the elastic member changes), the part closer to the waist opening WO side than the boundary closest to the waist opening WO side becomes the waist W. In the absence of such a boundary, the waist extension part 12E extending toward the waist opening WO side from the absorbent body 56 or the inner body 200 becomes the waist W. Their front-to-back lengths vary depending on the size of the product and can be appropriately determined. For example, the waist W can be 15 to 40 mm, and the lower waist part U can be 65 to 120 mm. On the other hand, the side edges of the middle area L are narrowed in a U-shaped or curved shape along the leg circumference of the wearer, and this is the part for the wearer's legs to enter. As a result, the pants-type disposable diaper in the unfolded state is formed into a roughly hourglass shape as a whole.

[0107] (inner body)

[0108] The inner body 200 can have any shape, but in the example shown in the figure, it is a rectangle whose long sides constitute the two side edges. Figure 3 to Figure 5 As shown in the figure, the inner body 200 comprises: a top sheet 30 on the body side; a liquid-impermeable sheet 11; and an absorbent member 50 interposed therebetween, and the inner body 200 is a part that performs the absorption / retention function. Reference numeral 40 denotes an intermediate sheet (second sheet) disposed between the top sheet 30 and the absorbent member 50 in order to allow the liquid that has passed through the top sheet 30 to move quickly to the absorbent member 50, and reference numeral 60 denotes standing pleats 60 extending from both sides of the inner body 200 in a manner that contacts the leg circumference of the wearer in order to prevent excrement from leaking to both sides of the inner body 200.

[0109] (Top sheet)

[0110] The top sheet 30 has a property of allowing liquid to penetrate, and for example, a porous or non-porous nonwoven fabric, a porous plastic sheet, etc. can be exemplified. In addition, the top sheet 30 can be composed of a sheet material, or a laminated sheet obtained by laminating two or more sheets. Similarly, the top sheet 30 can be composed of a sheet material, or two or more sheets in the plane direction.

[0111] The side portions of the top sheet 30 may be folded back at the side edges of the absorbent member 50 toward the back side of the absorbent member 50, or may not be folded back but may extend laterally beyond the side edges of the absorbent member 50. In addition, a structure may be provided in which the full width of the top sheet 30 is shorter than the full width of the absorbent member 50, the side edges of the top sheet 30 are located on the absorbent member 50, and the side portions of the front side of the absorbent member 50 are exposed at the front side of the diaper.

[0112] For the top sheet 30, for the purpose of preventing the position deviation of the back side component, it is desired to be fixed on the adjacent component on the back side by means of joining or hot melt adhesive based on material fusion such as heat sealing and ultrasonic sealing. In the illustrated example, the top sheet 30 is fixed on the front side of the front side of the part located at the front side of the absorbent 56 in the front of the intermediate sheet 40 and the packaging nonwoven fabric 58 by the hot melt adhesive applied on the back side.

[0113] (Middle piece)

[0114] In order to make the liquid after passing through the top sheet 30 move quickly to the absorbent 56, an intermediate sheet (also called "second sheet") 40 whose liquid penetration speed is faster than that of the top sheet 30 can be provided. The intermediate sheet 40 is used for the following purposes: to make the liquid move quickly to the absorbent to improve the absorption performance of the absorbent 56 and prevent the absorbed liquid from "flowing back" from the absorbent. The intermediate sheet 40 can also be omitted. In addition, in this case, the top sheet 30 can also be omitted.

[0115] As the middle sheet 40, the same material as the top sheet 30, or spunlace nonwoven fabric, spunbond nonwoven fabric, SMS nonwoven fabric, pulp nonwoven fabric, mixed sheet of pulp and artificial fiber, point-bonded nonwoven fabric or crepe paper can be exemplified. Hot air nonwoven fabric is particularly bulky and therefore preferred. For hot air nonwoven fabric, it is preferred to use a composite fiber with a core-sheath structure. In this case, the resin used for the core can be polypropylene (PP), but preferably polyester (PET) with high rigidity. The weight per unit area is preferably 17 to 80 g / m 2 , more preferably 25 to 60 g / m 2 The thickness of the raw material fiber of the nonwoven fabric is preferably 2.0 to 10 dtex. In order to make the nonwoven fabric bulky, eccentric fibers whose core is not in the center, hollow fibers, or eccentric and hollow fibers are preferably used as mixed fibers for all or part of the raw material fibers.

[0116] The middle piece 40 of the example of the figure is shorter than the width of the absorbent body 56 and is arranged in the center, and can also be set to cover the entire width. The front-to-back length of the middle piece 40 can be the same as the full length of the diaper, and can also be the same as the length of the absorbent member 50, and can also be within a shorter length range centered on the area receiving the liquid.

[0117] For the purpose of preventing the positional deviation of the back side components, it is desirable to fix the middle sheet 40 to the adjacent components on the back side by means of bonding such as heat sealing and ultrasonic sealing or hot melt adhesive. In the example shown in the figure, the middle sheet 40 is fixed to the front side of the portion of the packaging nonwoven fabric 58 located on the front side of the absorbent body 56 by the hot melt adhesive applied to the back side thereof.

[0118] (Liquid-impermeable sheet)

[0119] The material of the liquid-impermeable sheet 11 is not particularly limited, and examples thereof include a plastic film made of a polyolefin resin such as polyethylene or polypropylene, a laminated nonwoven fabric formed by providing a plastic film on the surface of a nonwoven fabric, and a laminated sheet formed by overlapping and bonding nonwoven fabrics on a plastic film. For the liquid-impermeable sheet 11, a material having liquid impermeability and moisture permeability is preferably used from the viewpoint of preventing stuffiness. As a plastic film having moisture permeability, a microporous plastic film obtained by mixing an inorganic filler in a polyolefin resin such as polyethylene or polypropylene and molding it into a sheet, and then stretching it in a uniaxial or biaxial direction is widely used. In addition, as the liquid-impermeable sheet 11, the following can be used: non-woven fabric using micro denier fibers; non-woven fabric whose leak-proofness is enhanced by applying heat or pressure to reduce the gaps between the fibers; and a sheet having liquid-impermeability without using a plastic film by coating a highly absorbent resin, a hydrophobic resin, or a water repellent. However, in order to obtain sufficient bonding strength when bonding to the cover non-woven fabric 13 described later by a hot-melt adhesive, it is preferably used a resin film.

[0120] In addition to being formed to have a width that converges on the back side of the absorbent member 50 as shown in the figure, the liquid-impermeable sheet 11 may also be extended to both sides of the absorbent member 50 and to both sides of the surface of the absorbent member 50 on the side of the top sheet 30 in order to improve the leakage prevention. The width of the extended part is preferably about 5 to 20 mm on the left and right sides.

[0121] (Absorbing member)

[0122] The absorbent member 50 includes an absorbent body 56 and a wrapping nonwoven fabric 58 that covers the entire absorbent body 56 .

[0123] (Absorber)

[0124] The absorbent body 56 is formed by mixing and agglomerating pulp fibers and superabsorbent polymer particles. The basis weight of the pulp fibers can be set to, for example, 100 to 450 g / m 2 about.

[0125] The superabsorbent polymer particles include "powder" in addition to "particles". As the superabsorbent polymer particles, particles used in such disposable diapers can be used as they are, and particles whose proportion of particles remaining on the sieve after sieving (vibrating for 5 minutes) using a 500 μm standard sieve (JIS Z8801-1:2006) is 30% by weight or less are preferred, and particles whose proportion of particles remaining on the sieve after sieving (vibrating for 5 minutes) using a 180 μm standard sieve (JIS Z8801-1:2006) is 60% by weight or more are preferred.

[0126] The material of the superabsorbent polymer particles can be used without particular limitation, but a material having a water absorption of 40 g / g or more is preferred. The superabsorbent polymer particles include starch, cellulose, synthetic polymer and the like superabsorbent polymer particles, and superabsorbent polymer particles such as starch-acrylic acid (salt) graft polymer, starch-acrylonitrile copolymer saponification product, sodium carboxymethyl cellulose crosslinked product and acrylic acid (salt) polymer can be used. The shape of the superabsorbent polymer particles is preferably a commonly used powdery granular shape, but other shapes can also be used.

[0127] As the super absorbent polymer particles, it is preferable to use super absorbent polymer particles having a water absorption rate of 70 seconds or less, particularly 40 seconds or less. If the water absorption rate is too slow, liquid supplied into the absorbent body 56 tends to return to the outside of the absorbent body 56, so-called backflow.

[0128] In addition, as the superabsorbent polymer particles, it is preferable to use superabsorbent polymer particles having a gel strength of not less than 1000 Pa. Thereby, even when the absorbent body 56 is formed into a bulky state, it is possible to effectively suppress the sticky feeling after absorbing liquid.

[0129] The basis weight of the superabsorbent polymer particles can be appropriately determined according to the absorption amount required according to the use of the absorbent body 56. Therefore, it cannot be generally stated, but it can be set to 50 to 350 g / m 2 If the unit area weight of the polymer is less than 50g / m 2 If it exceeds 350g / m 2 , the effect is saturated.

[0130] The ratio of pulp fibers to superabsorbent polymer particles in the absorbent body 56 is not particularly limited, and for example, the weight ratio of pulp fibers:superabsorbent polymer particles can be set to 40:60 to 65:35. In particular, if the weight ratio of pulp fibers:superabsorbent polymer particles is 50:50 to 65:35, the shape retention, absorption speed, and ease of forming the grooves 53 described later of the absorbent body 56 are excellent, and there is less concern about the superabsorbent polymer particles escaping, so it is preferred. In addition, the superabsorbent polymer particles are preferably present approximately uniformly throughout the entire absorbent body 56, but in order to suppress the superabsorbent polymer particles from escaping to the front side, it is preferred that the content of the superabsorbent polymer particles decreases stepwise or continuously as it moves from the back side to the front side, and it is particularly preferred as follows Fig.19 As shown, a covering layer 56c composed only of pulp fibers is provided to cover the front surface of the absorbent body 56. When the covering layer 56c composed only of pulp fibers is provided, the ratio of the fibers to the superabsorbent polymer particles is also preferably within the above range.

[0131] The thickness 56t of the absorber 56 is not particularly limited, and can be set to, for example, 3 to 15 mm.

[0132] The absorber 56 only needs to extend over both the front and rear sides of the crotch portion M in a manner including the crotch portion M. In the case of a shorts-type disposable diaper as in this example, it is preferred that the absorber 56 extends to the peripheral edge of the inner body 200 or its vicinity in the front-back direction LD and the width direction WD. In addition, reference numeral 56X indicates the full width of the absorber 56.

[0133] In order to ensure the absorption amount in the crotch portion M easily, the shape of the absorbent body 56 is preferably as follows: Figure 8 In addition, in order to improve the fit of the crotch portion M, the shape of the absorbent body 56 may also be as follows: Fig. 20 As shown in the example of (a), the width of the absorbent body 56 in the crotch portion M is narrowed as compared to the front and rear sides thereof. In this case, in order to easily ensure the absorption amount in the crotch portion M, the width n1 of the narrowest part of the absorbent body 56 in the crotch portion M is preferably 0.85 times or more of the full width 56X of the absorbent body 56.

[0134] In addition, when the absorbent body 56 has a narrowing portion 56n described later, the crotch portion M refers to the range in the front-to-back direction LD having the narrowing portion 56n. When the absorbent body 56 does not have the narrowing portion 56n, but the outer shape of the diaper in the unfolded state has the narrowing portion as shown in the example in the figure, the crotch portion M refers to the range in the front-to-back direction LD of the outer shape of the diaper having the narrowing portion (in the case of the example in the figure, it refers to the front outer body 12F and the rear outer body 12B). When there is no narrowing portion, the crotch portion M refers to the portion located in the center of the front-to-back direction LD and the dimension of the front-to-back direction LD is 20% to 30% of the total length of the product. The portions extending from the crotch portion M to the front and rear sides are the front side portion and the rear side portion, respectively.

[0135] (Low area weight)

[0136] The absorbent body 56 may be Figure 8 and Fig. 20 As shown in the figure, there are elongated low-basis-weight portions 56L extending in the front-rear direction LD on both sides of the crotch portion M in the width direction WD, and the like, or as shown in the figure, Figure 1 to Figure 6 As shown, there is no low unit weight portion 56L. The low unit weight portion 56L refers to a portion with a smaller unit weight, and does not include a portion that is only compressed in the thickness direction without changing the unit weight, such as the bottom 51 of the groove 53 described later. The low unit weight portion 56L can also be set as a gap that passes through the thickness direction, but if it is a recessed portion with a small amount of accumulation of pulp fibers and superabsorbent polymer particles as shown in the example, it is easy to ensure the absorption amount, so it is preferred. The recessed portion can be formed on the front side of the absorbent body 56, and can also be formed on the back side. By providing such a low unit weight portion 56L in the absorbent body 56, the bending of the absorbent body 56 along the low unit weight portion 56L is promoted, so that the fit of the absorption member 50 at the crotch portion M is improved. The total unit area weight of the pulp fibers and super absorbent polymer particles in the low unit area weight portion 56L only needs to be smaller than the total unit area weight of the pulp fibers and super absorbent polymer particles in the portion other than the low unit area weight portion 56L. For example, it can be set to 0.1 to 0.5 times the total unit area weight of the pulp fibers and super absorbent polymer particles in the portion other than the low unit area weight portion 56L.

[0137] The low unit area weight portion 56L only needs to be an elongated shape extending in the front-rear direction LD, and may extend in a straight line along the front-rear direction LD, or may be curved in a manner such that it is located laterally as it approaches both sides of the front-rear direction LD as shown in the example in the figure. In addition, the front and rear ends of the low unit area weight portion 56L can be set to appropriate shapes, for example, in addition to the Fig. 20 In addition to being set to a straight line as in the example shown in (a) of FIG. Figure 8As shown in the example, it is set to a curved bulging shape (semicircular arc shape, etc.), or, although not shown, the corners of the two end portions can be rounded and the middle portion can be made straight. The width m1 of the low unit weight portion 56L can be appropriately determined, for example, it can be set to 0.04 to 0.1 times the width n1 of the narrowest part of the absorbent body 56 in the crotch portion M (in the case of a rectangle, it refers to the full width 56X). The width m1 of the low unit weight portion 56L can be constant or variable in its length direction. The size and configuration of the low unit weight portion 56L in the front-to-back direction LD can be appropriately determined. For example, the size m2 of the low unit weight portion 56L in the front-to-back direction LD can be set to 50 to 120% of the size of the crotch portion M in the front-to-back direction LD, and more preferably to 50 to 80%. In addition, the low unit weight portion 56L can be either converging within the range of the crotch portion M, or extending to the front side, rear side, or both sides of the crotch portion M.

[0138] Regarding the low basis weight portion 56L, in addition to being provided one on each side (left and right sides) in the width direction WD of the crotch portion M, as shown in FIG. Figure 8 and Fig. 20 In addition to providing one in the center of the width direction WD as shown in (a), it is also possible to Fig. 20 As shown in (b), only one is provided on each side of the crotch portion M in the width direction WD, or although not shown in the figure, only one may be provided in the center in the width direction WD.

[0139] (groove)

[0140] As for the absorption member 50, it is preferred that Figure 3 , Figure 4 , Fig. 9 As shown, the grooves 53 which are recessed from the front side of the absorbent member 50 into the absorbent body 56 and have the bottom 51 compressed in the thickness direction are continuous in a lattice shape. By making the grooves 53 on the front side of the absorbent member 50 continuous in a lattice shape in this way, the liquid diffusibility and the shape retention of the absorbent body 56 can be improved. The bottom 51 of the groove 53 is a high-density portion which is compressed by pressing (direct pressure) and has a substantially equal thickness. Hereinafter, the portion other than the bottom 51 is referred to as a non-compressed portion 52. The non-compressed portion 52 is a portion which is thicker and has a lower density than the bottom 51, but even in the non-compressed portion 52, the absorbent body 56 and the packaging non-woven fabric 58 are deformed in a manner stretched by the deformation of the bottom 51 near the bottom 51, and as a result, the density increases as it approaches the bottom 51. As long as the non-compressed portion 52 is thicker and has a lower density than the bottom 51, the non-compressed portion 52 as a whole may be compressed in the thickness direction simultaneously with the compression process for forming the bottom 51, or before or after the compression process. The shape and arrangement of the non-compressed portion 52 are determined according to the shape and arrangement of the bottom portion 51 .

[0141] Preferably, the bottom 51 of the grooves 53 arranged in a grid pattern on the front surface of the absorbing member 50 has intersections 21 and non-intersections 22 located between adjacent intersections 21, and at least a portion of the front surface of the absorbing member 50, such as Fig.11 and Fig.12 As shown, the thickness of the bottom 51 gradually or continuously thickens as it moves from the center of the length direction of the non-intersecting portion 22 (the continuous direction XD of the groove 53) toward the intersection portion 21. It should be noted that the darker portion of the dot pattern in the figure represents a portion where the thickness of the bottom 51 of the groove 53 is relatively thin and is compressed at a relatively high density, and the lighter portion of the dot pattern represents a portion where the thickness of the bottom 51 of the groove 53 is relatively thick and is compressed at a relatively low density.

[0142] exist Fig.12 In the example shown in (a), the bottom 51 of the middle portion in the longitudinal direction of the non-intersection portion 22 has a substantially constant first thickness t1, and the bottom 51 of the other portion, i.e., the portion near the intersection portion 21 in the non-intersection portion 22, has a substantially constant second thickness t2 that is thicker than the first thickness t1. Fig.12 In the example shown in (b), the non-intersecting portion 22 has a substantially constant first thickness t1 in the longitudinal direction, and the bottom 51 of the intersecting portion 21 has a substantially constant second thickness t2 that is thicker than the first thickness t1 in the entirety. These are examples in which the thickness of the bottom 51 changes in stages.

[0143] On the other hand, Fig.12 In the example shown in (c), the bottom 51 of the central portion in the longitudinal direction of the non-intersection portion 22 has a substantially constant first thickness t1, and the bottom 51 of the intersection portion 21 has a substantially constant second thickness t2 that is thicker than the first thickness t1, and the portion between them continuously thickens (inclines) from the first thickness t1 to the second thickness t2. Fig.12 In the example shown in (d), the thickness of the bottom 51 is changed continuously in the longitudinal direction of the groove 53 (in the cross section along the continuous direction of the groove 53, the bottom surface of the groove 53 is in a sine wave or other wave shape) in such a manner that the thickness of the bottom 51 is the smallest (first thickness t1) at the approximate center of the length direction of the non-intersecting portion 22 and the thickness of the bottom 51 is the largest (second thickness t2) at the approximate center of the intersecting portion 21. These are examples in which the thickness of the bottom 51 changes continuously.

[0144] In such a thickness variation region of the bottom 51, (a) the thickness of the bottom 51 gradually or continuously increases as it approaches the intersection 21 from the center of the length direction of the non-intersection 22 (i.e., as it approaches the intersection 21 from the center of the length direction of the non-intersection 22, the degree of compression of the bottom 51 decreases, and the density of the bottom 51 decreases), thereby suppressing the thickness reduction of the corner of the non-compressed part 52 facing the intersection 21 of the bottom 51 of the groove 53, and the intersection 21 of the bottom 51 of the groove 53 is difficult to contact the user's skin. Therefore, compared with the case where the thickness of the bottom 51 of the groove 53 is approximately constant, the gritty touch of the superabsorbent polymer particles is difficult to be transmitted to the user. Furthermore, (b) at the intersection 21 of the bottom 51 of the groove 53 which is more likely to come into contact with the user's skin, the increase in the amount of superabsorbent polymer particles on the front side of the absorbent body 56 and its vicinity is suppressed, and the reduction and densification of the cushioning properties of the packaging non-woven fabric 58 and the absorbent body 56 in the thickness direction are also suppressed. Therefore, even if the intersection 21 of the bottom 51 of the groove 53 comes into contact with the user's skin, the gritty touch of the superabsorbent polymer particles is weaker, and therefore, the gritty touch of the superabsorbent polymer particles is more difficult to be transmitted to the user.

[0145] The aforementioned bottom thickness variation region may be throughout the entire region having the groove 53 (i.e., all the intersections 21 and non-intersections 22 may have the aforementioned thickness variation), or may be only a portion of the region having the groove 53. In particular, considering that the gritty touch of the superabsorbent polymer particles is easily generated in the portion subjected to external forces such as friction (the same is true for the case where the superabsorbent polymer particles escape from the surface of the packaging nonwoven fabric 58), as Figure 8 As shown, when the absorbent member 50 is divided into three regions 50C, 50L, and 50R (for example, divided into three equal parts) in the width direction WD, and a grid-like groove 53 is formed throughout the three regions 50C, 50L, and 50R, it is preferable that at least the regions 50L and 50R on both sides are set as the aforementioned bottom thickness change region. In addition, considering that if the thickness of the bottom 51 increases at the intersection 21, it is disadvantageous in terms of liquid diffusion or shape maintenance of the absorbent body 56, it is preferable that the thickness of the bottom 51 in the central region 50C has a first thickness t1 throughout the entire grid-like groove 53. In addition, it is also possible to set the central region 50C as the aforementioned bottom thickness change region, and in the following description Fig.16Taking the example as a reference, the areas 50L and 50R on both sides are set to a shape that the grooves 53 do not intersect (there is no recess (the part compressed in the thickness direction) in the part corresponding to the intersection 21), or the area of ​​the unit frame 51f of the groove 53 in the areas 50L and 50R on both sides is larger than the area of ​​the unit frame 51f of the groove 53 in the central area 50C (for example, more than 1.5 times). In this case, the gravel touch of the superabsorbent polymer particles is particularly difficult to be transmitted to the user, and the liquid diffusivity in the width direction WD is low, and side leakage is difficult to occur.

[0146] When the portion 24 having the first thickness t1 and the portion 23 having the second thickness t2 have lengths in the continuous direction XD of the groove 53 (i.e., except for the case where the thickness of the bottom 51 changes continuously), the length 23L of the portion 23 having the second thickness t2 in the continuous direction XD of the groove 53 is preferably 0.3 to 1 times, and particularly preferably 0.5 to 0.9 times, the length 22L of the non-intersecting portion 22 in the longitudinal direction. The length 24L of the portion 24 having the first thickness t1 in the continuous direction XD of the groove 53 is preferably 1 times or more, particularly preferably 1.1 times or more, the length 21L of the intersection 21 in the continuous direction XD of the groove 53 (the interval between a pair of non-intersecting portions 22 adjacent to each other across the intersection 21), and is preferably less than 0.75 times the length 22L of the non-intersecting portion 22 in the longitudinal direction.

[0147] Such an absorbent member 50 can be manufactured by a known method such as embossing. For example, the absorbent member 50 having the grooves 53 can be manufactured by performing the following steps: a first step of forming an absorbent body 56 in which pulp fibers and superabsorbent polymer particles are mixed and accumulated; a second step of forming a packaging body in which the entire absorbent body 56 is packaged with a packaging sheet 58; and a third step of forming a packaging body 58 in which the absorbent body 56 is packaged. Fig.21 As shown, the package 50P is passed between a support roller 90 having a plurality of protrusions 91 arranged at intervals in the same pattern as the bottom 51 of the groove 53 on the outer peripheral surface and a smooth roller 92 having a cylindrical surface (without the protrusions 91) facing the support roller 90 so that the surface that becomes the back side of the absorbing member 50 is on the support roller 90 side, and the groove 53 having the bottom 51 compressed in the thickness direction is formed by pressing the portion of the package 50P sandwiched between the plurality of protrusions 91 of the support roller 90 and the smooth roller 92. Pressing may be performed while heating one or both of the support roller 90 and the smooth roller 92, or may be performed without heating. In the third step, only the portion of the package 50P sandwiched between the multiple protrusions 91 of the support roller 90 and the smooth roller 92 may be pressed, or the entire package 50P may be pressed while the portion sandwiched between the multiple protrusions 91 of the support roller 90 and the smooth roller 92 is pressed to the deepest.

[0148] In the formation Fig.12 In the case of the groove 53 of the example shown in (a), the pattern of the protrusion 91 of the support roller 90 is as follows Fig. 22 As shown in (a), in the formation Fig.12 In the case of the groove 53 shown in the example of (c), the pattern of the protrusion 91 of the support roller 90 is as follows Fig. 22 As shown in (b). The bottom 51 of the first thickness t1 is formed by pressing the first protrusion 91a of the support roller 90, and the bottom 51 of the second thickness t2 is formed by pressing the second protrusion 91b. In addition, the inclined bottom 51 connecting the bottom 51 of the first thickness t1 and the bottom 51 of the second thickness t2 is formed by the inclined protrusion 91c connecting the first protrusion 91a and the second protrusion 91b.

[0149] The thickness 50t of the absorbing member 50 and the thickness 51t of the bottom 51 of the groove (t1, t2) can be appropriately determined, but for example, the maximum value of the thickness 50t of the absorbing member 50 (the maximum value of the thickness of the non-compressed portion 52) can be set to 4 to 35 mm, and particularly preferably 5 to 13 mm. The first thickness t1 of the bottom 51 can be appropriately determined, but in general, it is preferably 15 to 35% of the maximum value of the thickness 50t of the absorbing member 50. In addition, the second thickness t2 of the bottom 51 is preferably 1.4 to 6 times the first thickness t1, and more preferably 2 to 4 times.

[0150] like Fig.10 and Fig.11 As shown in the example, a preferred pattern of the groove 53 is an oblique lattice pattern composed of a first portion 51a and a second portion 51b, wherein the first portion 51a extends in a direction inclined 40° to 50° clockwise relative to the front-rear direction LD when viewed from above, and the second portion 51b extends in a direction inclined 40° to 50° counterclockwise relative to the front-rear direction LD when viewed from above. In this case, the shape of the unit frame 51f is roughly rhombus-shaped. The size of the unit frame 51f can be appropriately determined. For example, the size 51x of the unit frame 51f in the width direction WD can be set to about 15 to 20 mm. In addition, the size 51y of the unit frame 51f in the front-rear direction LD can be set to about 15 to 20 mm.

[0151] The width 51 w of the bottom 51 of the groove 53 can be appropriately determined, but is usually preferably approximately 1 mm to 3 mm, and is preferably substantially constant in the continuous direction of the groove 53 .

[0152] The area ratio of the bottom 51 of the groove 53 on the front surface of the absorbing member 50 can be appropriately determined. However, if the bottom 51 of the groove 53 is arranged too densely, the absorbing member 50 becomes hard. Therefore, it is preferably about 10% to 14%.

[0153] It is preferred that the non-compressed portion 52 at the intersection 21 has multiple corners and the angle of one corner is reduced as shown in the example in the figure. In this case, the intersection 21 refers to a portion formed by connecting all the corners (the octagonal portion shown in the figure). Similarly, it is also preferred to round the corners into an arc shape (not shown). In this case, the intersection 21 refers to a portion formed by connecting the end points of the arcs that are opposite to each other across the groove.

[0154] The area where the grooves 53 are continuous in a grid pattern may be the entire front surface of the absorbent member 50 or a part thereof. If the grooves 53 are continuous in a grid pattern, the liquid diffusibility is improved, but if they are located at the front end or rear end of the absorbent member 50, there is a concern that leakage from the front or rear may easily occur. Therefore, for example, Fig.16 As shown in (a), it is preferred that the absorbent member is divided into three parts, namely, a middle area 50M in the front-to-back direction LD including the crotch portion M, an area 50F on the front side of the middle area 50M, and an area 50B on the back side of the middle area 50M, and that grid-like continuous grooves 53 are provided throughout all of these areas, and that the area of ​​the unit frame 51f in the front area 50F and the back area 50B is made larger than the area of ​​the unit frame 51f in the middle area 50M (for example, about 1.5 to 3 times). In addition, as Fig.16 As shown in (b), it is also preferably configured as follows: continuous grooves 53 in a grid pattern are provided in the middle region 50M, and on the other hand, although grooves 53 are provided in the front region 50F and the rear region 50B, the grooves 53 are not intersected (there is no recess (a portion compressed in the thickness direction) in the portion corresponding to the intersection portion 21).

[0155] (Packaging non-woven fabric)

[0156] As the packaging nonwoven fabric 58, a nonwoven fabric having a meltblown layer formed of fibers having an average fiber diameter of 5 μm or less and having an air permeability of 25.5 to 70.0 cm2 by the A method (Frazier method) measured in accordance with JIS L 1096:2010 in a state where five sheets are stacked is suitable. 3 / cm 2 The air permeability of the packaging nonwoven fabric 58 in a state where five sheets are stacked is more preferably 40.0 to 70.0 cm 3 / cm 2·s. For example, the air permeability can be measured using an air permeability measuring instrument (model AP-500KZ4) of Daiei Kagaku Seiki Manufacturing Co., Ltd. As is well known, the meltblown layer is a non-woven fabric layer formed by accumulating ultrafine fibers obtained by spinning a molten resin raw material in a high-speed hot air flow and combining the fibers. The constituent fibers are long fibers with an average fiber diameter of less than 10 μm and a fiber length of more than 30 μm, and the fiber spacing is also small. The average fiber diameter of the fibers of the meltblown layer is preferably less than 2.5 μm. In addition, the average fiber diameter of the fibers of the meltblown layer can be set to be greater than 1 μm, preferably greater than 2 μm.

[0157] The total unit area weight of the meltblown layer (the sum of the unit area weights of all layers in the case of multiple meltblown layers) and the total thickness (the sum of the thicknesses of all layers in the case of multiple meltblown layers) can be appropriately determined. For example, the total unit area weight of the meltblown layer can be set to 0.3 to 6 g / m 2 The total thickness of the meltblown layer can be set to 0.01 to 0.35 mm.

[0158] As long as the packaging nonwoven fabric 58 has a meltblown layer, it can also be a single-layer nonwoven fabric consisting only of a meltblown layer, but it is preferably a laminated nonwoven fabric having one or more meltblown layers and one or more protective layers. The laminated nonwoven fabric can be manufactured by overlapping the webs constituting each layer in sequence, and then bonding the fibers and the layers by thermal bonding (point bonding, hot air bonding, etc.), or by forming the nonwoven fabric layers constituting each layer separately (web formation and fiber bonding), overlapping them, and bonding the layers by heat or an adhesive.

[0159] As a protective layer, a spunbond layer can be appropriately used. As is well known, a spunbond layer is a nonwoven fabric layer formed by accumulating filaments obtained by extruding (spinning) a molten resin raw material from a nozzle and bonding the fibers. The average fiber diameter of the constituent fibers is greater than that of the meltblown layer, and the fiber length is also longer than that of the meltblown layer. More specifically, as a packaging nonwoven fabric 58, SMS nonwoven fabrics, SSMMS nonwoven fabrics, etc., which are formed by sandwiching at least one meltblown layer with a pair of spunbond layers on both sides, can be appropriately used. The material of the constituent fibers of each layer is not particularly limited. For example, polypropylene fibers, polyethylene / polypropylene bicomponent fibers, etc. can be used for the meltblown layer, and polypropylene fibers, polyethylene / polypropylene bicomponent fibers, etc. can be used for the spunbond layer.

[0160] The fiber diameter, total weight per unit area (the sum of the weight per unit area of ​​all layers in the case of multiple protective layers), and total thickness (the sum of the thickness of all layers in the case of multiple protective layers) of the constituent fibers of the protective layer can be appropriately determined. For example, the constituent fibers of the protective layer are preferably fibers having an average fiber diameter of 10 to 25 μm (particularly preferably 15 to 20 μm). In addition, the total weight per unit area of ​​the protective layer is preferably 5 to 17.5 g / m 2 (5 to 10 g / m is particularly preferred) 2 ), the total thickness of the protective layer is preferably 0.01 to 0.35 mm (particularly preferably 0.1 to 0.2 mm).

[0161] The weight per unit area and thickness of the packaging nonwoven fabric 58 can be appropriately determined. For example, the total weight per unit area of ​​the packaging nonwoven fabric 58 is preferably 10 to 17 g / m 2 In addition, the thickness of the packaging nonwoven fabric 58 is preferably 0.2 to 0.8 mm.

[0162] If the wrapping nonwoven fabric 58 is not easily stretched, it is not only difficult to form a strong groove 53, but also the flexibility of the absorbent member 50 is reduced. Therefore, it is preferable that the wrapping nonwoven fabric 58 has a stretching rate of 20 to 100% in the front-back direction LD according to the standard specified in JIS L 1913: 2010, and preferably 30 to 60%, and a stretching rate of 20 to 110% in the width direction WD according to the standard specified in JIS L 1913: 2010, and preferably 50 to 70%. When the same groove is formed using such a nonwoven fabric, the gritty touch of the superabsorbent polymer particles is easily transmitted to the user, but by providing the above-mentioned bottom thickness change area, the shape retention and flexibility of the absorbent body 56 can be improved while suppressing the gritty touch of the superabsorbent polymer particles from being transmitted to the user.

[0163] When the following nonwoven fabric is used as the packaging nonwoven fabric 58, the weight per unit area of ​​the packaging nonwoven fabric 58 is set to 15 to 17 g / m 2, and by adopting the aforementioned thickness variation region of the bottom 51, the superabsorbent polymer particles are not easy to escape to the outside of the packaging nonwoven fabric 58, so it is preferred that the nonwoven fabric has one or more meltblown layers composed of fibers with an average fiber diameter of 5 μm or less, and one or more protective layers composed of fibers with an average fiber diameter of 10 to 25 μm, and has the above-mentioned elongation. That is, if the thickness of the bottom 51 gradually or continuously thickens as it approaches the intersection 21 from the center of the length direction of the non-intersection 22 (that is, as it approaches the intersection 21 from the center of the length direction of the non-intersection 22, the degree of compression of the bottom 51 becomes weaker and the density of the bottom 51 becomes lower), then compared with the case where this is not the case, the elongation of the packaging nonwoven fabric 58 at both sides of the groove 53 can be suppressed as it approaches the intersection 21 from the center of the length direction of the non-intersection 22. The expansion of the fiber gap and the reduction of the thickness caused by this can be suppressed. Therefore, if a dense packaging nonwoven fabric 58 having a certain weight per unit area is combined with the aforementioned change in thickness of the bottom 51, the highly absorbent polymer particles contained in the absorbent body 56 will have difficulty passing through the packaging nonwoven fabric 58 even at the intersection 21 of the groove 53 and its vicinity.

[0164] The packaging structure of the packaging nonwoven fabric 58 can be appropriately determined, but from the perspective of ease of manufacturing and preventing leakage of highly absorbent polymer particles from the front and rear edges, it is preferred that the nonwoven fabric 58 be wound into a tube in a manner that surrounds the front, back and both side surfaces of the absorbent body 56, as shown in the example in the figure, and the front and rear edges are extended from the front and rear of the absorbent body 56, and the overlapping parts of the winding and the overlapping parts of the front and rear extended parts are joined by hot-melt adhesives, material welding or other joining means.

[0165] In particular, Fig.15 As shown, the packaging nonwoven fabric 58 has: a back portion 58s, which is located on the back side of the absorbent body 56; a first front side portion 58a, which is a portion continuous with the back portion 58s, bypassing one side edge of the absorbent body 56 to reach the front side of the absorbent body 56; and a second front side portion 58b, which is a portion continuous with the back portion 58s, bypassing the other side edge of the absorbent body 56 to reach the back side of the absorbent body 56. The first front side portion 58a and the second front side portion 58b have a stacked portion 58W that overlaps with each other. If all the grooves are formed in the stacked portion 58W, it is also possible to suppress the high-absorbent polymer particles from escaping from the surface of the absorbent member 50, so it is preferred.

[0166] In order to reduce the cost, the absorbing member 50 may also be Fig. 9 As shown in the figure, there is no other sheet layer such as paper or nonwoven fabric between the packaging nonwoven fabric 58 and the absorbent body 56 (of course, an adhesive layer may also be provided), or other sheet layers may be provided on at least one side of the front and back of the absorbent body 56.

[0167] (Stand up pleats)

[0168] The standing gathers 60 have standing parts 68 standing up from the side of the inner body 200, and the standing parts 68 are in contact with the range from the groin to the buttocks of the wearer to prevent side leakage. Regarding the standing gathers 60 shown in the figure, the root side part 60B stands up obliquely toward the center side in the width direction, and the part 60A closer to the end side than the middle part stands up obliquely toward the outside in the width direction, but it is not limited to this, and it can also be appropriately changed such as a method of standing up the whole toward the center side in the width direction.

[0169] To explain in more detail, the standing gather 60 shown in the figure is configured as follows: a band-shaped gathering sheet 62 having a length equal to the length of the inner body 200 in the front-back direction is folded back in the width direction WD at a portion that becomes a terminal and folded into two layers, and a plurality of elongated gathering elastic members 63 are fixed in the width direction WD in a state of being stretched in the longitudinal direction between the folded portion and the sheet material in the vicinity thereof. The base end portion (the end portion on the side opposite to the sheet material folded back in the width direction WD) of the standing gather 60 located on the side opposite to the terminal portion is a root portion 65 fixed to the side portion of the inner body 200, and the portion other than the root portion 65 is a main body portion 66 (the portion on the folded back portion side) extending from the root portion 65. In addition, the main body portion 66 includes a root side portion 60B extending toward the center side in the width direction and a terminal side portion 60A folded back at the terminal of the root side portion 60B and extending toward the outer side in the width direction. Furthermore, the two end portions in the front-to-back direction of the main body portion 66 are inverted portions 67 fixed to the side front surface of the top sheet 30 in a inverted state, and on the other hand, the middle portion in the front-to-back direction between them is a non-fixed standing portion 68, and the pleated elastic component 63 along the front-to-back direction LD is fixed to at least the terminal portion of the standing portion 68 in a stretched state.

[0170] In the standing gathers 60 constructed as described above, the standing portions 68 are contracted by the contraction force of the gather elastic members 63 as shown in FIG. Figure 3 In particular, if the root portion 65 is located on the back side of the inner body 200, the standing portion 68 stands up in a manner that opens outward in the width direction in the crotch portion and its vicinity, so that the standing pleats 60 are in surface contact with the leg area, thereby improving the fit. The root portion 65 can also be fixed to the front side of the inner body 200, for example, the front side of both sides of the top sheet 30.

[0171] In the curved structure in which the main body 66 is composed of the root side portion 60B extending to the central side in the width direction and the terminal side portion 60A extending to the outside in the width direction by folding back at the end of the root side portion 60B, at the prostrate portion 67, the terminal side portion 60A and the root side portion 60B are joined together in the prostrate state, and the root side portion 60B is joined to the top sheet 30 in the prostrate state. For the joining of the opposite surfaces in the prostrate portion 67, at least one of the means based on material welding such as hot melt adhesives based on various coating methods and heat sealing, ultrasonic sealing, etc. can be adopted. In this case, the joining of the root side portion 60B and the top sheet 30 and the joining of the terminal side portion 60A and the root side portion 60B can be carried out by the same means, or by different means. For example, it is preferable that the base side portion 60B and the top sheet 30 are joined by a hot melt adhesive, and the tip side portion 60A and the base side portion 60B are joined by material welding.

[0172] As the pleated sheet 62, a fabric made by water-repellent treatment of soft nonwoven fabrics with excellent uniformity and concealment such as spunbond nonwoven fabrics (SS, SSS, etc.) or SMS nonwoven fabrics (SMS, SSMMS, etc.), meltblown nonwoven fabrics, etc., using silicone or the like as needed can be appropriately used. The fiber unit area weight of the nonwoven fabric in this case is preferably about 10 to 30 g / m 2 Although not shown in the figure, a waterproof membrane may be interposed between the folded pleat sheets 62 .

[0173] As the pleated elastic component 63, a rubber thread or the like can be used. When using a spandex rubber thread, the thickness is preferably 470 to 1240 dtex, and more preferably 620 to 940 dtex. The elongation of the pleated elastic component 63 in the installed state is preferably 150 to 350%, and more preferably 200 to 300%. Regarding the number of pleated elastic components 63, it is preferably 2 to 6, and more preferably 3 to 5. The configuration interval of the pleated elastic component 63 is preferably 3 to 10 mm. If it is constructed like this, it is easy to contact the skin with the surface within the range where the pleated elastic component 63 is configured. It is also possible to configure the pleated elastic component 63 not only on the terminal side but also on the root side.

[0174] In the rising portion 68 of the rising pleats 60, for the bonding of the inner layer and the outer layer of the pleated sheet 62, or the fixing of the pleated elastic member 63 sandwiched therebetween, at least one of a hot melt adhesive by various coating methods and a fixing means by material fusion such as heat sealing or ultrasonic sealing can be adopted. If the inner layer and the outer layer of the pleated sheet 62 are bonded to each other over the entire surface, the flexibility is impaired, and therefore, it is preferable not to bond or to bond weakly to the portion other than the bonding portion of the pleated elastic member 63. In the example shown in the figure, the structure is as follows: the hot-melt adhesive is applied only to the outer peripheral surface of the pleated elastic component 63 by using a coating means such as a coating gun or a gluing nozzle, and the pleated elastic component 63 is sandwiched between the inner layer and the outer layer of the pleated sheet 62. Thus, the pleated elastic component 63 is fixed relative to the inner layer and the outer layer of the pleated sheet 62, and the inner layer and the outer layer of the pleated sheet 62 are fixed to each other using only the hot-melt adhesive applied to the outer peripheral surface of the pleated elastic component 63.

[0175] Similarly, the inverted portion 67 may be fixed by at least one of a hot melt adhesive using various coating methods and a material welding method such as heat sealing or ultrasonic sealing.

[0176] (flank)

[0177] Preferably, if Figure 1 to Figure 4 As shown in the figures, side wings 70 extending to the sides of the absorbent body 56 are provided on both sides of the inner body 200, and side stretch regions SG that stretch in the front-back direction are formed on the side wings 70. The side wings 70 shown in the figure have: one or more elongated side elastic members 73 that are arranged along the front-back direction LD and spaced apart from each other; a first sheet layer 71 that faces the outside of the side elastic members 73; and a second sheet layer 72 that faces the inside of the side elastic members 73.

[0178] The sheet material constituting the first sheet layer 71 and the second sheet layer 72 is not particularly limited, and an appropriate nonwoven fabric such as a nonwoven fabric that can be used in the aforementioned standing gathers 60 or the aforementioned outer body 12F, 12B can be selected. In the example shown in the figure, the pleated sheet 62 of the standing gathers 60 is extended as described later to form the first sheet layer 71 and the second sheet layer 72. In this case, the front and rear ends of the side flaps 70 coincide with the front and rear ends of the standing gathers 60 (that is, the front and rear ends of the inner body 200 in this case).

[0179] The side elastic members 73 are not particularly limited, and the same elongated elastic members as the aforementioned gather elastic members 63 can be used. The elongation of the side elastic members 73 in the mounted state is preferably 150 to 350%, more preferably 200 to 270%. The number of the side elastic members 73 is preferably 2 to 16, more preferably 6 to 10. The arrangement interval of the side elastic members 73 is preferably 5 mm to 10 mm.

[0180] The side elastic member 73 is fixed to the first sheet layer 71 and the second sheet layer 72. For the bonding of the first sheet layer 71 and the second sheet layer 72, or the fixing of the side elastic member 73 sandwiched therebetween, a hot melt adhesive HM based on various coating methods, or a fixing means based on material fusion such as heat sealing or ultrasonic sealing can be adopted. If the bonding area between the first sheet layer 71 and the second sheet layer 72 is large, the flexibility will be impaired, therefore, it is preferred that the portion other than the bonding portion of the side elastic member 73 is not bonded or is weakly bonded. In the example shown in the figure, the structure is as follows: the hot-melt adhesive HM is applied only to the outer peripheral surface of the side elastic component 73 by using a coating means such as a coating gun or a gluing nozzle, and the side elastic component 73 is sandwiched between the first sheet layer 71 and the second sheet layer 72. Thus, the side elastic component 73 is fixed relative to the first sheet layer 71 and the second sheet layer 72, and the first sheet layer 71 and the second sheet layer 72 are fixed to each other using only the hot-melt adhesive HM applied to the outer peripheral surface of the side elastic component 73.

[0181] In the example shown in the figure, the sheet material constituting the first sheet layer 71 and the sheet material constituting the second sheet layer 72 are folded back at the side edges of the side flaps 70, and the folded back portions are fixed to the back surface (bag-like closure) of the liquid-impermeable sheet 11. This fixing can be performed by welding the materials in addition to using the hot melt adhesive HM as shown in the example shown in the figure.

[0182] The side wings 70 may also be omitted.

[0183] (outer body)

[0184] The outer body 12F and 12B may be, as shown in the example in the figure, a rectangular front outer body 12F which is a part of at least the waistline of the front body F, and a rectangular rear outer body 12B which is a part of at least the waistline of the rear body B, wherein the front outer body 12F and the rear outer body 12B are discontinuous on the crotch side and separated in the front-to-back direction LD (exterior two-part type); in addition, although not shown in the figure, it may also be continuous from the front body to the rear body (exterior one-piece type). The separation distance 12d in the front-to-back direction in the exterior two-part type may be, for example, about 40 to 60% of the total length Y. In the example in the figure, the lower edges of the front outer body 12F and the rear outer body 12B are straight lines along the width direction WD, but the lower edge of at least one of the front outer body 12F and the rear outer body 12B may also be a curved line along the leg circumference.

[0185] In the outer two-part type shorts-type disposable diaper, since the inner body 200 is exposed between the front outer body 12F and the rear outer body 12B, it is preferred to have a cover nonwoven fabric 13, wherein the cover nonwoven fabric 13 extends from between the front outer body 12F and the inner body 200 to between the rear outer body 12B and the inner body 200 on the back side of the inner body 200, so as to prevent the liquid-impermeable sheet 11 from being exposed on the back side of the inner body 200. The inner surface and the outer surface of the cover nonwoven fabric 13 can be bonded to the opposite surface respectively by a hot melt adhesive. For the nonwoven fabric used for the cover nonwoven fabric 13, for example, the same material as that of the outer body 12F and 12B can be appropriately selected. In addition, although not shown in the figure, the outer body can also be continuous from the front body part F to the back body part B through the crotch. In this case, the outer body has not only a portion corresponding to the waist area T, but also a portion corresponding to the middle area L.

[0186] The front outer body 12F and the rear outer body 12B have a front waistline portion and a rear waistline portion constituting the waistline region T. Figure 1 and Figure 2 In the example shown, the front outer body 12F and the rear outer body 12B have the same size in the front-rear direction LD, and the front outer body 12F and the rear outer body 12B do not have a portion corresponding to the middle area L, but as shown in FIG. Figure 7 As shown, the dimension of the rear outer body 12B in the front-to-back direction may be longer than that of the front outer body 12F, and the front outer body 12F may not have a portion corresponding to the middle region L, but the rear outer body 12B may have a buttocks cover portion C extending from the waist region T to the middle region L. Although not shown, a groin cover portion extending from the waist region T to the middle region L may also be provided on the front outer body 12F.

[0187] like Figure 4 and Figure 5 As shown, the outer body 12F, 12B is formed by joining the outer layer and the inner layer adjacent to the outer side and the inner side of the elastic member 16 to 19 described later by means of hot melt adhesive or welding. The outer layer and the inner layer can be formed by a sheet material in addition to being formed by two sheets 12S and 12H as shown in the example. For example, in the latter case, in a part or all of the outer body 12F, 12B, the inner layer and the outer layer are formed by the inner part and the outer part of a sheet material folded back at the edge of the waist opening WO (or at the edge of the crotch side). The example shown is an example of the former, the sheet material 12S forming the outer layer in the lower waist part bypasses the waist opening WO side of the sheet material 12H forming the inner layer in the lower waist part and folds back to the inside thereof, and the folded part 12r extends in a way that covers the end of the waist opening WO side of the inner body 200. On the other hand, in the waist region, the folded portion 12r serves as an inner sheet adjacent to the inner side of the elastic member.

[0188] In order to improve the fit for the wearer's waist, elastic components 16 to 19 are built into the outer bodies 12F and 12B, thereby forming an elastic region A2 that elastically expands and contracts in the width direction WD as the elastic components 16 to 19 expand and contract. In the elastic region A2, the outer bodies 12F and 12B contract as the elastic components contract in the natural length state, thereby forming wrinkles or pleats. When the outer bodies 12F and 12B are stretched in the longitudinal direction of the elastic components, they can be stretched to a prescribed elongation as follows: limit elongation without wrinkles. As elastic components 16 to 19, in addition to slender elastic components such as rubber threads (examples shown in the figure), known elastic components such as belt-shaped, mesh-shaped, and film-shaped can also be used without particular limitation. As elastic components 16 to 19, synthetic rubber or natural rubber can be used.

[0189] The elastic components 16 to 19 shown in the figure are described in more detail. A plurality of waist elastic components 17 are installed at intervals in the front-to-back direction on the waist W of the outer body 12F, 12B in a continuous manner throughout the entire width direction WD. In addition, one or more of the waist elastic components 17 arranged in the area adjacent to the lower waist portion U may overlap with the inner body 200, or may be respectively arranged on both sides in the width direction thereof without removing the central portion in the width direction overlapping with the inner body 200. As the waist elastic component 17, it is preferred to have a thickness of about 155 to 1880 dtex, particularly about 470 to 1240 dtex (in the case of synthetic rubber. In the case of natural rubber, the cross-sectional area is 0.05 to 1.5 mm 2 Around, especially 0.1~1.0mm 2 The elastic cords (2 to 15, especially 4 to 10) are arranged at intervals of 2 to 12 mm, especially at intervals of 3 to 7 mm, and the elongation of the waist W in the width direction WD obtained thereby is preferably about 150 to 400%, especially about 220 to 320%. In addition, for the waist W, it is not necessary to use elastic components of the same thickness or to set the same elongation in the entire front-to-back direction LD thereof, and for example, the thickness or elongation may be partially different.

[0190] In addition, a plurality of elastic members 16 and 19 of the waist below the outer body 12F and 12B are installed at intervals in the front-to-back direction, which are composed of slender elastic members, so as to form a waist below stretch area (an area having elastic members 16 and 19 of the waist below). As the elastic members 16 and 19 of the waist below, it is preferred that the thickness is about 155 to 1880 dtex, especially about 470 to 1240 dtex (in the case of synthetic rubber. In the case of natural rubber, the cross-sectional area is 0.05 to 1.5 mm 2Around, especially 0.1~1.0mm 2 The elastic cords (about 5 to 30) are arranged at intervals of 1 to 15 mm, especially at intervals of 3 to 8 mm, and the elongation of the lower waist portion U in the width direction WD obtained thereby is preferably about 200 to 350%, especially about 240 to 300%. In addition, for the lower waist portion U, it is not necessary to use elastic components of the same thickness or to set the same elongation in the entire front-to-back direction LD thereof, and the thickness or elongation may be partially different.

[0191] When elastic members 16 and 19 are provided in the front-back direction range of the absorbent body 56 as in the lower waist portion U shown in the example, in order to prevent the absorbent body 56 from shrinking in the width direction WD in part or all of the absorbent body 56, it is preferable that Figure 4 , Figure 5 as well as Fig. 20 As shown in the figure, the middle in the width direction including a part or all of the part overlapping with the absorber 56 in the width direction WD is set as the non-elastic region A1, and the two sides in the width direction thereof are set as the elastic regions A2 (the waist-lower elastic regions in the example shown in the figure). The size in the width direction of the elastic regions A2 provided on the two sides in the width direction of the non-elastic region A1 is substantially constant in the front-back direction LD as shown in the example shown in the figure, but although not shown in the figure, it may also be changed in the front-back direction LD. In addition, the size in the width direction WD of the elastic regions A2 provided on the two sides in the width direction WD of the non-elastic region A1 may be substantially the same in the front body part F and the back body part B, but may also be different.

[0192] Such stretchable region A2 and non-stretchable region A1 can be constructed by installing elastic members 16 to 17, 19 between the inner sheet and the outer sheet, and then thinly cutting the elastic members 16 and 19 at one location in the middle of the width direction of the region to be the non-stretchable region A1 or substantially all over by pressurizing and heating, or by cutting, so that the stretchability is retained in the stretchable region A2 and the stretchability is eliminated in the non-stretchable region A1. In addition, in the non-stretchable region A1, there remain excess elastic members 18 that do not substantially contribute to the formation of stretchability.

[0193] The sheets 12S and 12H forming the inner and outer sheets can be used without particular limitation, but nonwoven fabrics are preferred. When nonwoven fabrics are used, the weight per unit area of ​​each sheet is preferably 10 to 30 g / m 2 about.

[0194] The elastic components 16 to 19 can be fixed to the outer body 12F, 12B by a known method. In addition, the inner sheet and the outer sheet can also be joined to each other by a known method. For example, in the portion of the outer body 12F, 12B having the elastic components 16 to 19, a hot melt adhesive HM is applied only on the outer peripheral surface of the elastic components 16 to 19 by a coating means such as a coating gun or a gluing nozzle and the elastic components 16 to 19 are sandwiched between the inner sheet and the outer sheet, thereby, the elastic components 16 to 19 can be fixed relative to the inner sheet and the outer sheet, and the inner sheet and the outer sheet can be fixed only by the hot melt adhesive HM applied to the outer peripheral surface of the elastic components 16 to 19.

[0195] (Inner body joint)

[0196] The inner body 200 can be joined to the outer body 12F, 12B by a joining method based on material fusion such as heat sealing or ultrasonic sealing, or by a hot melt adhesive. In the example shown in the figure, the inner body 200 is fixed to the inner surface of the outer body 12F, 12B by a hot melt adhesive applied to the back surface of the liquid-impermeable sheet 11 and the root portion 65 of the standing gathers 60 in this case. The inner body joint 20 that joins the inner body 200 to the outer body 12F, 12B can be as follows: Figure 2 As shown, the plurality of connectors are provided in substantially the entire region where the two overlap, and for example, may be provided in a portion other than both end portions in the width direction of the inner body 200 .

[0197] Since the superabsorbent polymer particles can be prevented from escaping through the packaging nonwoven fabric 58 as described above, Fig.17 and Fig.18 As shown in the figure, the top sheet 30 and the middle sheet 40 and other components covering the front of the absorption member 50 can be omitted, and in this case, a significant cost reduction can be achieved. In this case, as long as the middle part of the front of the absorption member 50 except the two end parts in the width direction WD is not covered by other components throughout the entire front-back direction LD so that the packaging nonwoven fabric 58 is exposed on the front, it can also be that only the middle part in the width direction WD is not covered by other components as in the example in the figure, or it can be that the entire front of the absorption member 50 is not covered by other components.

[0198] <Effect confirmation test>

[0199] The following shorts-type disposable diaper samples 1 to 8 were prepared: Fig.17 and Fig.18 As shown in FIG. 1 , the top sheet 30 and the intermediate sheet 40 are omitted, and the width of the joining area between the absorbent member 50 and the liquid-impermeable sheet 11 is enlarged. Figure 1 to Figure 6The structure is the same as that shown in Table 1. Other specifications are shown in Table 1. In addition, except for the specifications shown in Table 1, each sample is the same. For these samples 1 to 8, the surface of the intersection is lightly traced with a finger, and the presence or absence of the gritty touch of the superabsorbent polymer particles is evaluated with two levels of ○ (no feeling or a few particles are felt) and × (gritty touch is felt). In addition, for these samples 1 to 8, a superabsorbent polymer particle release confirmation test was performed for the release feeling described below.

[0200] (Test for confirmation of release of superabsorbent polymer particles)

[0201] exist Fig.23 The test device 80 is shown in the figure. The test device 80 is constructed by fixing a recovery tray 83 for receiving superabsorbent polymers on a vibration table 82b of a vibrator 82 (MK161 manufactured by Yamato Science Co., Ltd.) disposed on a horizontal plane 81, and erecting and fixing a friction body 84 composed of a metal cylinder (with a diameter of 55 mm) in the center of the recovery tray 83. The recovery tray 83 and the friction body 84 vibrate integrally with the vibration table 82b. The distance d1 between the upper surface of the friction body 84 and the upper surface of the vibration table 82b in the vertical direction is 72 mm. In addition, a pair of pedestals 85 are erected and fixed on both sides of the vibrator 82 in the horizontal direction on the horizontal plane 81. Set the sample 86 in an unfolded state (such as Figure 1 As shown), the sample 86 is stretched between the pedestals 85 and fixed to the pedestals 85 in a manner that the front side (the exposed side of the packaging nonwoven fabric) of the sample 86 faces downward. At this time, the front-to-back direction LD of the sample 86 becomes the major axis direction BD of the ellipse in the oscillation mode. In addition, in a state where the friction body 84 is not set in a manner that the front side of the sample 86 is in contact with the friction body 84, the distance d2 in the vertical direction between the friction body contact portion on the front side of the sample 86 and the upper surface of the vibration table 82b is 71 mm. Next, the vibration mode of the vibrator 82 is set to an ellipse (amplitude w1 in the major axis direction: 30 mm; amplitude w2 in the minor axis direction: 20 mm), and vibrated at a rotation speed of 90 rpm for 2 minutes, as shown. Fig.24 As shown, the friction body 84 is moved elliptically to rub the front side of the sample 86, and then the number of high absorbent polymer particles falling onto the recovery tray 83 is counted.

[0202] The test results are shown in Table 1. In the case of Samples 1 and 5, there was a gritty touch and superabsorbent polymer particles fell out, whereas Samples 2, 3, 4, 6, 7, and 8 did not have a gritty touch and did not have superabsorbent polymer particles fall out despite having continuous grid-like grooves.

[0203] [Table 1]

[0204]

[0205] <Explanation of terms used in this manual>

[0206] Unless otherwise specified in the specification, the following terms in the specification have the following meanings.

[0207] The “front-rear direction” refers to the direction (longitudinal direction) indicated by symbol LD in the figure, and the “width direction” refers to the direction (left-right direction) indicated by WD in the figure. The front-rear direction and the width direction are perpendicular to each other.

[0208] The “front side” refers to the side close to the skin of the wearer when worn, and the “back side” refers to the side away from the skin of the wearer when worn.

[0209] The “front side” refers to the side close to the skin of the wearer when worn, and the “back side” refers to the side away from the skin of the wearer when worn.

[0210] "Elongation" means a value when the natural length is 100%. For example, an elongation of 200% is equivalent to an elongation of 2 times.

[0211] Artificial urine is a mixture of 2 wt% urea, 0.8 wt% sodium chloride, 0.03 wt% calcium chloride dihydrate, 0.08 wt% magnesium sulfate heptahydrate, and 97.09 wt% ion-exchanged water.

[0212] "Gel strength" was measured as follows. 1.0 g of a high absorbent polymer was added to 49.0 g of artificial urine and stirred with a stirrer. The resulting gel was placed in a constant temperature and humidity chamber at 40°C x 60% RH for 3 hours and then returned to room temperature. The gel strength was measured using a curdmeter (manufactured by I.techno Engineering: Curdmeter-MAX ME-500).

[0213] The “average fiber diameter” is determined by observing the target layer at a magnification of 1000 times using a microscope (optical microscope, SEM, etc.), randomly selecting 30 constituent fibers, measuring the fiber diameters (μm), and calculating the average value.

[0214] ·The "weight per unit area" is measured as follows. After pre-drying the sample or test piece, place it in a test room or device under standard conditions (the temperature of the test site is 23±1°C and the relative humidity is 50±2%) to make it a constant state. Pre-drying means making the sample or test piece a constant in an environment with a temperature of 100°C. In addition, for fibers with an official regain of 0.0%, pre-drying is not required. Use a template (100mm×100mm) for sample selection to cut a sample of 100mm×100mm size from the test piece in a constant state. Measure the weight of the sample and calculate 100 times the weight per square meter as the weight per unit area.

[0215] ·For the "thickness" of thicker parts such as the absorbent body 56, the absorbing member 50, and the bottom 51 of the groove 53, use a thickness gauge (PEACOCK, dial-type thickness gauge, model JB (measuring range 0 to 35 mm, circular terminal with a measuring area diameter of 20 mm, measuring force of approximately 3.0 N, pressure of approximately 30 KPa)) produced by Ozaki Manufacturing Co., Ltd., and make the sample and the thickness gauge level for measurement.

[0216] For the thickness of thinner sheets such as non-woven fabrics, use an automatic thickness gauge (KES-G5 portable compression measurement program) at a load of 0.098N / cm 2 , Pressurized area: 2cm 2 The “thickness” of the packaging nonwoven fabric refers to the thickness of the portion where the thickness 50t of the absorbing member 50 becomes the maximum value.

[0217] The "layer thickness" of the nonwoven fabric is obtained by observing the cross section of the target layer at the portion where the thickness 50t of the absorbent member 50 is the maximum value using a microscope (optical microscope or SEM, etc.) at a magnification of 1000 times, randomly selecting 5 measurement locations, measuring the apparent thickness, and calculating the average value.

[0218] The “area ratio” refers to the ratio of the area of ​​the target portion per unit area, and is obtained by dividing the total area occupied by the target portion (e.g., the bottom 51 of the groove 53) in the entire target region (e.g., the back side of the absorbent member 50) by the area of ​​the target region and expressing the result as a percentage.

[0219] The water absorption is measured in accordance with JIS K7223-1996 "Test method for water absorption of super absorbent resin".

[0220] The water absorption rate is the “time to the end point” when JIS K7224-1996 “Water absorption rate test method for super absorbent polymers” is carried out using 2 g of a super absorbent polymer and 50 g of physiological saline.

[0221] The “expanded state” refers to a state in which the garment is not contracted (including any contraction due to the elastic member, etc.) or is relaxed and flatly expanded.

[0222] · Unless otherwise specified, the dimensions of each part refer to the dimensions in the unfolded state, not the natural length state.

[0223] In the absence of any description of the environmental conditions during a test or measurement, the test or measurement was conducted in a test room or device under standard conditions (temperature of 23±1°C and relative humidity of 50±2% at the test site).

[0224] Industrial Applicability

[0225] The present invention can be used for all absorbent articles such as underpants-type disposable diapers, belt-type disposable diapers, and pad-type disposable diapers, as well as sanitary napkins.

[0226] Description of symbols

[0227] 11…Liquid-impermeable sheet; 12A…Side seal; 12B…Rear outer body; 12E…Waist extension; 12F, 12B…Outer body; 12F…Front outer body; 12S, 12H…Sheet; 13…Hood nonwoven fabric; 16, 19…Elastic components below the waist; 17…Waist elastic components; 18…Excess elastic components; 200…Inner body; 201…Inner body joint; 21…Intersection; 22…Non-intersection; 30…Top sheet; 40…Intermediate sheet; 50…Absorbent member; 51…Bottom; 51f…Unit frame; 52…Non-compressible portion; 53: Groove; 56: Absorbent; 56L: Low unit area weight portion; 56c: Cover layer; 57: Backflow prevention layer; 58: Wrapping nonwoven fabric; 60: Standing pleats; 60A: End side portion ; 60B: root side part; 62: pleated sheet; 63: pleated elastic component; 67…falling part; 68…standing part; 70…side wing; 71…first sheet layer; 72…second sheet layer; 73…side elastic component; 90…support roller; 91…protrusion; 92…smooth roller; A1…non-stretching area; A2…stretching area; B…back part; C…hip cover; F…front part; HM…hot melt adhesive; HM1…first hot melt adhesive; HM2…second hot melt adhesive; L…middle area; LD…front and back direction; LO…leg opening; M…crotch; SG…side stretching area; T…waist area; U…lower part of waist; W…waist; WD…width direction; WO…waist opening; t1…first thickness; t2…second thickness.

Claims

1. An absorbent article, characterized in that: The absorbent article comprises a crotch portion, and a front side portion and a rear side portion extending from the crotch portion toward the front side and the rear side, respectively. The absorbent article includes an absorbent member having an absorbent body provided at a position including the crotch portion, and a wrapping nonwoven fabric wrapping the absorbent body. The absorbent body has a layer in which pulp fibers and superabsorbent polymer particles are mixed and accumulated. In the absorbent member, grooves which are recessed from the front surface of the absorbent member into the absorbent body and have bottoms compressed in the thickness direction are continuous in a lattice shape, and, The groove has an intersection portion and a non-intersection portion located between adjacent intersection portions, and in at least a portion of the front surface of the absorbent member, the thickness of the bottom portion gradually or continuously thickens as it moves from the center of the non-intersection portion in the length direction toward the intersection portion.

2. The absorbent article according to claim 1, wherein The weight per unit area of ​​the pulp fibers in the absorbent is 100 g / m 2 ~450g / m 2 , The pulp fibers in the absorbent body have a weight ratio of 30:70 to 70:30 for superabsorbent polymer particles. The maximum thickness of the absorption member is 4 mm to 35 mm. The thickness of the bottom portion at the center of the non-intersecting portion in the longitudinal direction is 15% to 35% of the maximum thickness of the absorbing member. The thickness of the bottom portion at the intersection portion is 1.4 to 6 times the thickness of the bottom portion at the center in the longitudinal direction of the non-intersection portion.

3. The absorbent article according to claim 1 or 2, wherein: The width of the bottom is 1 mm to 3 mm, The groove is formed in an oblique lattice shape consisting of a first portion and a second portion, wherein the first portion is inclined 40° to 50° clockwise relative to the front-rear direction in a plan view, and the second portion is inclined 40° to 50° counterclockwise relative to the front-rear direction in a plan view.

4. The absorbent article according to claim 1 or 2, wherein: The packaging nonwoven fabric comprises one or more meltblown layers and one or more protective layers. The unit area weight of the packaging nonwoven fabric is 10 g / m 2 ~17g / m 2 , The protective layer is made of fibers with an average fiber diameter of 10 μm to 25 μm. The constituent fibers of the meltblown layer are fibers having an average fiber diameter of 5 μm or less. The air permeability of the packaging nonwoven fabric was 25.5 cm when the A method (Frazier method) was measured in accordance with JIS L 1096:2010 in a state where five sheets of the packaging nonwoven fabric were stacked. 3 / cm 2 ·s~70.0cm 3 / cm 2 ·s, The packaging nonwoven fabric has an elongation of 20% to 100% in the front-to-back direction according to the standard specified in JIS L 1913:2010, The packaging nonwoven fabric has an elongation in the width direction of 20% to 110% according to the standard specified in JIS L 1913:2010.

5. The absorbent article according to claim 4, wherein: The unit area weight of the packaging nonwoven fabric is 15 g / m 2 ~17g / m 2 .

6. The absorbent article according to claim 1 or 2, wherein: The absorbent body has a cover layer composed of only accumulated pulp fibers covering the front side of the absorbent body.

7. The absorbent article according to claim 1 or 2, wherein: The packaging nonwoven fabric comprises: a back portion, which is located on the back side of the absorbent body; a first front side portion, which is a portion continuous with the back portion, bypassing one side edge of the absorbent body and reaching the front side of the absorbent body; and a second front side portion which is a portion continuous with the back side portion and which goes around the other side edge of the absorbent body to reach the front side of the absorbent body, The first front side portion and the second front side portion have a stacked portion that overlaps each other. All of the grooves are formed in the laminated portion.

8. The absorbent article according to claim 5, wherein The middle portion of the absorbent member except for both ends in the width direction is not covered by other members throughout the entire front-back direction, and the wrapping nonwoven fabric is exposed on the front side of the absorbent article.

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