Absorbent article

Abstract

The present invention addresses the problem of improving the shape retention of an absorber and preventing the removal of highly absorbent polymer particles. The problem is solved by the following scheme: the absorbent article is provided with an absorbent member (50), the absorbent member (50) is provided with an absorbent body (56) and a packaging non-woven fabric (58) wrapping the absorbent body (56), the absorbent body (56) is provided with a layer formed by mixing and gathering pulp fibers and highly absorbent polymer particles, and the packaging non-woven fabric (58) wraps the absorbent body (56). The packaging non-woven fabric (58) has a melt-blown layer comprising fibers having an average fiber diameter of 5 [mu] m or less, and has an air permeability of 25.5-70.0 cm3 / cm2 * s as measured according to JIS L1096: 2010 in an A-method (Frazier-type method) in a state in which five sheets are stacked, and the air permeability of the packaging non-woven fabric (58) is 25.5-70.0 cm3 / cm2 * s as measured according to JIS L1096: 2010. Compressed parts (51) which are compressed in the thickness direction so as to be recessed into the absorber (56) from the rear surface of the absorber (50) are provided in the absorber (50) at intervals, and compressed parts (51) which are compressed in the thickness direction so as to be recessed into the absorber (56) from the front surface of the absorber (50) are not provided in the absorber (50).

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 aggregating 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 into the form of an absorbent member formed by winding a packaging sheet made of crepe paper or the like (for example, see 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 the crotch portion is required to have good fit, and on the other hand, it is also required to have shape retention to prevent the shape of the absorbent body from being damaged such as wrinkles and damage. Of course, the absorbent member of a disposable diaper is also required to ensure absorption performance in the crotch portion.

[0004] As a method for improving the shape retention of the absorbent body, there is a known method of providing a compressed portion formed by compressing the absorbent member in the thickness direction by embossing or the like in a grid-like pattern (for example, see 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 damaged at the edge of the compressed portion or between adjacent compressed portions. In addition, the strength of the crepe paper decreases in a wet state after absorbing excrement, and it is easy to be damaged. If the packaging sheet is damaged, the superabsorbent polymer particles may escape from there and overflow onto the surface of the absorbent article, which is not preferred.

[0005] It is also known that a nonwoven fabric with a fine mesh is used as a packaging sheet. The nonwoven fabric is not easily damaged even when wet, and is expected to effectively prevent the escape of the superabsorbent polymer particles. However, it has been confirmed that even if the packaging sheet is a nonwoven fabric, the escape of the superabsorbent polymer particles exceeds expectations.

[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 object of the present invention is to improve the shape-maintaining property of the absorbent body and to prevent superabsorbent polymer particles from appearing on the surface of the absorbent article.

[0012] Means for solving problems

[0013] The inventors have conducted intensive research and found that, when the packaging sheet is a nonwoven fabric, when the compressed portion is formed, the nonwoven fabric is stretched at the edge of the compressed portion or between adjacent compressed portions, thereby increasing the fiber gaps and making it easier for the superabsorbent polymer particles to escape from the portions. The absorbent article described below is based on this technical idea.

[0014] <Method 1>

[0015] An absorbent article, characterized in that

[0016] The invention comprises a crotch portion, and a front side portion and a rear side portion extending from the crotch portion to the front side and the rear side, respectively.

[0017] The invention is provided with an absorbing member having an absorbent body provided in a front-back direction range 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 aggregated.

[0019] The packaging nonwoven fabric has a meltblown layer formed of fibers having an average fiber diameter of 5 μm or less, and has an air permeability of 25.5 to 70.0 cm2 by the A method (Frazier method) measured in accordance with JIS L 1096:2010 when five sheets are stacked. 3 / cm 2 ·s non-woven fabric,

[0020] The absorbing member is provided with compressed portions at intervals in the thickness direction so as to be recessed from the back surface of the absorbing member into the absorbent body, and

[0021] The absorbent member is not provided with a compressed portion compressed in the thickness direction so as to be recessed from the surface of the absorbent member into the absorbent body.

[0022] (Effect)

[0023] The absorbent article is characterized in that

[0024] (a) By using a nonwoven fabric with a dense meltblown layer in the packaging material of the absorbent, the problems of using crepe paper (such as damage during manufacturing or use) are solved;

[0025] (b) by providing a compressed portion that is recessed from the back side of the absorbing member into the absorbent body, the shape retention of the absorbent body is improved; and

[0026] (c) By not providing a compressed portion that is recessed from the surface of the absorbent member to the inside of the absorbent body, the fiber gaps in the portion (surface portion) of the packaging nonwoven fabric that covers the surface of the absorbent member will not be widened, thereby maintaining a state in which the highly absorbent polymer particles contained in the absorbent body are not easily able to escape through the surface portion of the packaging sheet.

[0027] Thus, while providing the compressed portion as in the related art to improve the shape retention of the absorbent body, etc., it is also possible to effectively suppress the escape of the superabsorbent polymer particles which is a problem at this time.

[0028] Note that air permeability is also an indicator of the ease with which superabsorbent polymer particles can escape.

[0029] <Method 2>

[0030] The absorbent article according to the first aspect, wherein:

[0031] The packaging nonwoven fabric has one or more layers of the meltblown layer and one or more layers of protective layer.

[0032] The protective layer is made of fibers having an average fiber diameter of 10 to 25 μm.

[0033] The elongation of the packaging nonwoven fabric in the front-to-back direction according to the standard specified in JIS L 1913:2010 is 20 to 100%.

[0034] The elongation in the width direction according to the standard specified in JIS L 1913:2010 is 20 to 110%.

[0035] (Effect)

[0036] If the packaging nonwoven fabric is not easily stretched, it is not only difficult to form a firm compression portion (i.e., it is difficult to improve the shape retention), but also the softness of the absorbent body is reduced. Therefore, it is preferred that the packaging nonwoven fabric is sufficiently thin and easy to stretch as in this embodiment. Moreover, in such a nonwoven fabric, the fiber gap is easily increased due to the formation of the compression portion, but by having the above-mentioned features (a) to (c), it is possible to take into account both the improvement of the shape retention and softness of the absorbent body and the suppression of the escape of the superabsorbent polymer particles.

[0037] <Third Method>

[0038] The absorbent article according to the first or second aspect, wherein:

[0039] The weight per unit area of ​​the pulp fibers in the absorbent is 100 to 450 g / m 2 ,

[0040] The weight ratio of pulp fiber to superabsorbent polymer particles in the absorbent is 30:70 to 70:30.

[0041] The maximum thickness of the above-mentioned absorbing member is 4 to 35 mm.

[0042] The thickness of the compressed portion is 15 to 35% of the maximum value of the thickness of the absorbing member.

[0043] (Effect)

[0044] The material composition of the absorbent body and the degree of compression of the compressed portion can be appropriately determined, but are preferably within the range of the present embodiment.

[0045] <Method 4>

[0046] The absorbent article according to the third aspect, wherein:

[0047] The width of the compressed portion is 1 to 3 mm.

[0048] The compression portion is formed in an oblique lattice shape including a first portion inclined 40 to 50 degrees clockwise relative to the front-rear direction in a plan view and a second portion inclined 40 to 50 degrees counterclockwise relative to the front-rear direction in a plan view.

[0049] (Effect)

[0050] The size and shape of the compressed portion can be appropriately determined, but when it is formed into an oblique lattice shape as in this embodiment, not only the shape retention and softness of the absorbent are excellent, but also the diffusibility of the liquid is excellent, so it is preferred. However, when the compressed portion is formed in the pattern of this embodiment, the packaging nonwoven fabric is particularly easy to stretch, so it is particularly important to have the above-mentioned features (a) to (c).

[0051] <Method 5>

[0052] The absorbent article according to any one of the first to fourth aspects, wherein the absorbent body has a covering layer composed of only accumulated pulp fibers covering the surface of the absorbent body.

[0053] (Effect)

[0054] When a covering layer such as this embodiment is provided, the superabsorbent polymer particles are less likely to fall out from the surface of the absorbent body, which is preferred.

[0055] <Sixth Method>

[0056] The absorbent article according to any one of the first to fifth aspects, wherein:

[0057] The packaging nonwoven fabric comprises: a surface portion located on the surface side of the absorbent body; a first back side portion which is a portion continuous from the surface portion and which bypasses one side edge of the absorbent body to reach the back side of the absorbent body; and a second back side portion which is a portion continuous from the surface portion and which bypasses the other side edge of the absorbent body to reach the back side of the absorbent body.

[0058] The first back side portion and the second back side portion have a stacked portion overlapping each other,

[0059] The compressed portions are entirely formed in the laminated portions.

[0060] (Effect)

[0061] When configured as in this aspect, it is also possible to suppress the superabsorbent polymer particles from coming out from the back surface of the absorbent member.

[0062] <Seventh Method>

[0063] In the absorbent article according to any one of the first to sixth aspects, the intermediate portion of the absorbent member excluding both ends in the width direction is not covered by other members in the entire front-back direction, and the wrapping nonwoven fabric is exposed on the surface of the absorbent article.

[0064] (Effect)

[0065] Since the superabsorbent polymer particles passing through the wrapping nonwoven fabric can be prevented from escaping as described above, components such as a top sheet covering the surface of the absorbent member provided in conventional absorbent articles can be omitted, and in this case, significant cost reduction can be achieved.

[0066] <Method 8>

[0067] The absorbent article according to any one of the first to seventh aspects, wherein:

[0068] A liquid-impermeable sheet bonded to the back of the absorbent member by a hot-melt adhesive,

[0069] The liquid-impermeable sheet extends from a position further forward than the front edge of the absorbent member to a position further rearward than the rear edge of the absorbent member, and from a position further left than the left edge of the absorbent member to a position further right than the right edge of the absorbent member.

[0070] The hot melt adhesive is applied from a position forward of the front edge of the absorbent body to a position backward of the rear edge of the absorbent body, and from between the left edge of the absorbent body and the left edge of the absorbent member to between the right edge of the absorbent body and the right edge of the absorbent member.

[0071] (Effect)

[0072] By applying the hot melt adhesive for bonding the back surface of the absorbent member over the entire range of this embodiment, it is possible to suppress a decrease in the flexibility of both side edges of the absorbent member and effectively suppress the superabsorbent polymer particles from coming out of the back surface of the absorbent member.

[0073] Effects of the Invention

[0074] According to the present invention, there are advantages such as improving the shape-maintaining property of the absorbent body and making it difficult for superabsorbent polymer particles to appear on the surface of the absorbent article. BRIEF DESCRIPTION OF THE DRAWINGS

[0075] Figure 1 It is a top view showing the inner surface of the pants-type disposable diaper in the unfolded state.

[0076] Figure 2 It is a top view showing the outer surface of the pants-type disposable diaper in the unfolded state.

[0077] Figure 3 yes Figure 1 2-2 cross-sectional view.

[0078] Figure 4 yes Figure 1 3-3 cross-sectional view.

[0079] Figure 5 In (a), Figure 1 4-4 cross-sectional view, and (b) is Figure 1 Sectional view 5-5.

[0080] Figure 6 It is a three-dimensional diagram of a shorts-type disposable diaper.

[0081] Figure 7 It is a plan view showing the outer surface of the inner body in the unfolded state together with the outline of the outer body.

[0082] Figure 8 It is a top view showing the surface of the absorbent body together with the outline of the packaging sheet.

[0083] Fig. 9 is a cross-sectional view of the absorbing member.

[0084] Fig.10 is a top view of the absorbing member.

[0085] Fig.11 This is an enlarged view of a main part of the surface of the absorbent member.

[0086] Fig.12 It is a top view showing another example of the absorber.

[0087] Fig.13This is a cross-sectional view showing the absorbent member in a state before the absorbent body is packaged with a packaging sheet.

[0088] Fig.14 This is a cross-sectional view of the absorbent member showing a state after the absorbent body is packaged with the packaging sheet and before the compressed portion is formed.

[0089] Fig.15 is a cross-sectional view of other absorbing members.

[0090] Fig.16 is a top view of other absorbing members.

[0091] Fig.17 is with Figure 1 The cross section 2-2 is equivalent to a cross-sectional view of another example.

[0092] Fig.18 is with Figure 1 The cross section of 3-3 is equivalent to a cross-sectional view of other examples.

[0093] Fig.19 is a cross-sectional view of other absorbing members.

[0094] Fig. 20 is a cross-sectional view of other absorbing members.

[0095] Fig.21 is a schematic diagram illustrating a method of manufacturing an absorbing member.

[0096] Fig. 22 is a schematic diagram of the experimental apparatus.

[0097] Fig.23 It is an explanatory diagram showing only the friction mode of the main part. DETAILED DESCRIPTION

[0098] Hereinafter, as an example of a disposable diaper, a pants-type disposable diaper will be described in detail with reference to the accompanying drawings. Each component adjacent in the thickness direction is fixed or joined in the same manner as a known diaper as required, except for the fixing portion or joining portion described below. The dot pattern portion in the cross-sectional view represents an adhesive such as a hot melt adhesive as the fixing means or joining means. The hot melt adhesive can be applied by a known method such as slit coating, continuous linear or dotted droplet coating, spiral, Z-shaped, corrugated spray coating, or pattern coating (transfer of hot melt adhesive in relief mode). In the fixing portion of the elastic component, instead of this method or in combination with it, the hot melt adhesive can be applied to the outer peripheral surface of the elastic component to fix the elastic component to the adjacent component. As the hot melt adhesive, for example, there are adhesives of the type such as EVA, adhesive rubber (elastic system), polyolefin, polyester·polyamide, etc., which can be used without special limitation. As a fixing means or joining means for joining the components, means based on material welding such as heat sealing or ultrasonic sealing can 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, intermittent pattern coating in a spiral, Z-shaped, corrugated shape, etc. can be appropriately adopted. In the case of coating in a range larger than the coating width using a single nozzle, intermittent pattern coating in a spiral, Z-shaped, corrugated shape, etc. can be performed with or without intervals in the width direction. As a joining means for joining the components, means based on material welding such as heat sealing or ultrasonic sealing can also be used.

[0099] In addition, as the nonwoven fabric in the following description, known nonwoven fabrics can be appropriately used according to the location and purpose. As the constituent fibers of the nonwoven fabric, in addition to synthetic fibers such as polyolefins such as polyethylene or polypropylene, polyesters, and polyamides (in addition to single-component fibers, composite fibers such as core-sheath fibers are also included), regenerated fibers such as rayon or cuprammonia fibers, natural fibers such as cotton, etc. can be selected without particular limitation, 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 hydrophilic fibers (including fibers made hydrophilic by using a hydrophilic agent), or can be hydrophobic fibers or water-repellent fibers (including fibers made water-repellent by using 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 having a meltblown layer sandwiched between spunbond layers), etc., according to the fiber length, sheet forming method, fiber bonding method, and layered structure. Any of these nonwoven fabrics can be used.

[0100] 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 provided on the inner side of the outer bodies 12F and 12B in a manner extending from the front outer body 12F through the crotch portion M to the rear outer body 12B. 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 side seals 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 respectively 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 holds excreta such as urine, and the outer bodies 12F and 12B are parts for supporting the inner body 200 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), and the symbol X represents the full width of the diaper in the unfolded state.

[0101] The shorts-type disposable diaper has a waist region T defined as the front-to-back range with side seals 12A (the front-to-back range from the waist opening WO to the upper end of the leg openings LO); and a middle region L defined as the front-to-back range of the portion forming the leg openings LO (between the front-to-back region with side seals 12A of the front body portion F and the front-to-back region with 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 portion and the back waist portion can be conceptually divided into a "waist portion" W forming the edge portion of the waist opening, and a portion "waist lower portion" U 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 and elongation of the elastic member change), 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 to the waist opening WO side from the absorbent body 56 or the inner body 200 becomes the waist W. The lengths of these in the front-to-back direction 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 into a U-shape or a curve shape in a manner along the leg circumference of the wearer, and this becomes a part for the wearer's legs to enter. As a result, the unfolded shorts-type disposable diaper forms a roughly hourglass shape as a whole.

[0102] (inner body)

[0103] The inner body 200 may be in any shape, but is a rectangular shape in the example shown. Figure 3 to Figure 5 As shown in the figure, the inner body 200 comprises a top sheet 30 constituting the body side, a liquid-impermeable sheet 11, and an absorbent member 50 interposed therebetween, which is a main body part that bears the absorption function. Reference numeral 40 indicates an intermediate sheet (auxiliary sheet) disposed between the top sheet 30 and the absorbent member 50 in order to quickly transfer the liquid that has passed through the top sheet 30 to the absorbent member 50, and reference numeral 60 indicates a standing pleat portion 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.

[0104] (Top sheet)

[0105] The top sheet 30 has the property of making liquid permeable, for example, can illustrate porous or non-porous nonwoven fabrics, porous plastic sheets etc. In addition, the top sheet 30 can be composed of one sheet, and can also be composed of the laminated sheet obtained by laminating more than two sheets. Similarly, the top sheet 30 can be composed of one sheet in the planar direction, and can also be composed of more than two sheets.

[0106] The side portions of the top sheet 30 may be folded back toward the back side at the side edges of the absorbent member 50 , or may extend to the sides of the side edges of the absorbent member 50 without being folded back.

[0107] The top sheet 30 is fixed to the adjacent components on the back side by a bonding means or hot melt adhesive based on material fusion such as heat sealing and ultrasonic sealing for the purpose of preventing the position deviation of the components on the back side. In the example of the figure, the top sheet 30 is fixed to the surface of the intermediate sheet 40 and the surface of the part on the surface side of the absorbent 56 in the packaging nonwoven fabric 58 by the hot melt adhesive applied on the back side thereof.

[0108] (Middle piece)

[0109] In order to quickly transfer the liquid that has passed through the top sheet 30 to the absorbent 56, an intermediate sheet (also referred to as a "second sheet") 40 having a faster liquid penetration rate than the top sheet 30 may be provided. The intermediate sheet 40 is used to quickly transfer the liquid to the absorbent so as to improve the absorption performance based on the absorbent 56 and prevent the "re-seepage" phenomenon of the absorbed liquid from the absorbent. The intermediate sheet 40 may also be omitted. In addition, in this case, the top sheet 30 may also be omitted.

[0110] As the middle sheet 40, the same material as the top sheet 30, spunlace nonwoven fabric, spunbond nonwoven fabric, SMS nonwoven fabric, pulp nonwoven fabric, mixed sheet of pulp and rayon, point-bonded nonwoven fabric or crepe paper can be exemplified. Hot air nonwoven fabric is particularly preferred because it is fluffy. In hot air nonwoven fabric, it is preferred to use a composite fiber with a core-sheath structure. In this case, the resin used in the core can be polypropylene (PP), but polyester (PET) with high rigidity is preferred. 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, it is also preferable to use mixed fibers of eccentric fibers whose core is not located at the center, hollow fibers, and eccentric and hollow fibers as all or part of the raw material fibers.

[0111] The middle piece 40 of the illustrated example is shorter than the width of the absorbent body 56 and is arranged in the center, but it can also be arranged over the entire width. The front-to-back length of the middle piece 40 can be the same as the full length of the diaper, can 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.

[0112] The intermediate sheet 40 is fixed to the adjacent components on the back side by a joining method based on material welding such as heat sealing or ultrasonic sealing or a hot melt adhesive for the purpose of preventing the components from being displaced relative to the back side. In the example shown in the figure, the intermediate sheet 40 is fixed to the surface of the portion located on the front side of the absorbent body 56 in the packaging nonwoven fabric 58 by a hot melt adhesive applied on the back side thereof.

[0113] (Liquid-impermeable sheet)

[0114] 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 a nonwoven fabric on a plastic film. In the liquid-impermeable sheet 11, a material having liquid-impermeability and moisture-permeability is preferably used, which is preferably used from the perspective of preventing stuffiness. As a moisture-permeable plastic film, a microporous plastic film obtained by kneading an inorganic filler in a polyolefin resin such as polyethylene or polypropylene, and then stretching it in a uniaxial or biaxial direction after forming a sheet can be widely used. In addition, nonwoven fabrics using micro denier fibers; nonwoven fabrics whose leak-proof properties are enhanced by reducing the gaps between fibers by applying heat or pressure; and sheets that are made liquid-impermeable without using plastic films by methods such as coating with superabsorbent resins or hydrophobic resins or water repellents can also be used as the liquid-impermeable sheet 11. However, in order to obtain sufficient bonding strength when bonding with the cover nonwoven fabric 13 described later by means of hot-melt adhesives, it is preferably used a resin film.

[0115] In addition to being set to a width that fits into the back side of the absorbent member 50 as shown in the figure, the liquid-impermeable sheet 11 may also extend to both sides of the side of the top sheet 30 of the absorbent member 50 by bypassing both sides of the absorbent member 50 to improve leakage prevention. The width of the extended portion is preferably about 5 to 20 mm on both sides.

[0116] (Absorbing member)

[0117] The absorbent member 50 includes an absorbent body 56 and a wrapping nonwoven fabric 58 that wraps the entire absorbent body 56 .

[0118] (Absorber)

[0119] The absorbent body 56 is formed by mixing and aggregating pulp fibers and superabsorbent polymer particles. The basis weight of the pulp fibers may be, for example, 100 to 450 g / m 2 about.

[0120] The superabsorbent polymer particles include "powders" in addition to "particles". As the superabsorbent polymer particles, the superabsorbent polymer particles used in such disposable diapers can be used directly, for example, preferably particles whose proportion of particles remaining on the sieve after sieving (vibrating for 5 minutes) using a 500 μm standard sieve (JIS Z 8801-1:2006) is 30% by weight or less, and preferably particles whose proportion of particles remaining on the sieve after sieving (vibrating for 5 minutes) using a 180 μm standard sieve (JIS Z 8801-1:2006) is 60% by weight or more.

[0121] The material of the superabsorbent polymer particles can be used without particular limitation, but preferably a material having a water absorption of 40 g / g or more. The superabsorbent polymer particles include starch-based, cellulose-based, synthetic polymer-based superabsorbent polymer particles, and superabsorbent polymer particles such as starch-acrylic acid (salt) graft copolymers, starch-acrylonitrile copolymer saponification products, sodium carboxymethyl cellulose crosslinked products, and acrylic acid (salt) polymers 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.

[0122] As the superabsorbent polymer particles, it is preferable to use superabsorbent 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, so-called back permeation (liquid supplied to the absorbent body 56 returns to the outside of the absorbent body 56) is likely to occur.

[0123] 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 liquid absorption.

[0124] The basis weight of the superabsorbent polymer particles can be appropriately determined according to the absorption amount required for the use of the absorbent body 56. Therefore, it cannot be generalized, but it can be 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 reaches saturation.

[0125] The ratio of fibers and superabsorbent polymer particles in the absorbent body 56 is not particularly limited, and for example, the weight ratio of fibers:superabsorbent polymer particles can be 40:60 to 65:35. In particular, when the weight ratio of fibers:superabsorbent polymer particles is 50:50 to 65:35, the absorbent body 56 is excellent in shape retention, absorption speed, and ease of forming the compression portion 51 described later, and the possibility of superabsorbent polymer particles escaping is low, so it is preferred. In addition, the superabsorbent polymer particles are preferably present roughly uniformly throughout the entire absorbent body 56, but in order to suppress the superabsorbent polymer particles from escaping to the surface side, it is preferred that the content of the superabsorbent polymer particles decreases stepwise or continuously from the back side toward the surface 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 surface of the absorbent body 56. Even when the covering layer 56c composed only of pulp fibers is provided, the ratio of the fibers to the superabsorbent polymer particles is preferably within the above range.

[0126] The thickness 56t of the absorber 56 is not particularly limited, and may be 3 to 15 mm.

[0127] The absorber 56 may be extended to 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, the absorber 56 preferably extends to the peripheral edge of the inner body 200 or its vicinity in the front-back direction LD and the width direction WD. It should be noted that the symbol 56X represents the full width of the absorber 56.

[0128] In the case where the absorption amount of the crotch portion M is easily ensured, the absorbent body 56 is preferably as follows Figure 8 As shown in the example, it is roughly rectangular in shape. Fig.12As shown in the example of (a), in order to improve the fit of the crotch M, the width of the absorbent body 56 in the crotch M may be narrower than the front and rear sides thereof to form a narrowed shape. In this case, in order to easily ensure the absorption amount of the crotch M, it is preferred that the width n1 of the narrowest part of the absorbent body 56 in the crotch M is at least 0.85 times the full width 56X of the absorbent body 56.

[0129] It should be noted that, regarding the crotch portion M, when the absorbent body 56 has a narrowing portion 56n described later, it refers to the range of 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, it refers to the range of the outer shape of the diaper having the narrowing portion in the front-to-back direction LD (in the case of the example shown, it refers to the front outer body 12F and the rear outer body 12B); when there is no narrowing portion, it 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 referred to as the front side portion and the rear side portion.

[0130] (Low area weight)

[0131] The absorbent body 56 may be Figure 8 and Fig.12 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 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 small unit weight, and does not include a portion that is only compressed in the thickness direction without changing the unit weight, such as the compression portion 51 described later. The low unit weight portion 56L can also be set as a slit running through the thickness direction, but when it is a recessed portion with a small amount 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 surface of the absorbent body 56, and can also be formed on the back. 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 can be promoted, and the fit of the absorption member 50 of the crotch M can be 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 less 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 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.

[0132] The low unit area weight portion 56L only needs to be an elongated shape extending in the front-to-back direction LD, and may extend in a straight line in the front-to-back direction LD, or may be curved in a manner that it is located laterally as it moves toward both sides of the front-to-back 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 may be of appropriate shapes, for example, in addition to the Fig.12 In addition to being a straight line as in the example shown in (a) of FIG. Figure 8 As shown in the example, it is a curved bulging shape (semicircular arc shape, etc.). Although not shown in the figure, 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 0.04 to 0.1 times the width n1 of the narrowest part of the absorbent body 56 in the crotch 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 in its length direction or it can change. The size and configuration of the front-to-back direction LD of the low unit weight portion 56L can be appropriately determined. For example, the size m2 of the front-to-back direction LD of the low unit weight portion 56L can be 50 to 120% of the size of the front-to-back direction LD of the crotch M, and more preferably 50 to 80%. In addition, the low unit weight portion 56L can be retracted within the range of the crotch M, or it can extend to the front, rear, or front and rear sides of the crotch M.

[0133] The low unit area weight portion 56L may be provided with one each on both sides (left and right sides) in the width direction WD of the crotch portion M, and as shown in FIG. Figure 8 and Fig.12 In addition to providing one in the center of the width direction WD as shown in (a), it is also possible to Fig.12 As shown in (b) of FIG. 1 , only one may be provided on each side of the crotch portion M in the width direction WD, or, although not shown, only one may be provided in the center in the width direction WD.

[0134] (Compression section)

[0135] In the absorption member 50, as Figure 3 , Figure 4 , Fig. 9As shown in the figure, the compressed parts 51 compressed in the thickness direction in a manner of being recessed from the back side of the absorbing member 50 into the absorbent body 56 are provided at intervals. In addition, the compressed parts 51 compressed in the thickness direction in a manner of being recessed from the surface of the absorbing member 50 into the absorbent body 56 are not provided in the absorbing member 50. The compressed parts 51 are high-density parts that are compressed by pressing (direct pressure) and have a substantially equal thickness, and are the bottoms of the recesses. Hereinafter, the parts other than the compressed parts 51 are referred to as non-compressed parts 52. The non-compressed parts 52 are parts that are thicker and have a lower density than the compressed parts 51, but even in the non-compressed parts 52, the absorbent body 56 and the packaging non-woven fabric are deformed in a manner of being stretched by the deformation of the compressed parts 51 near the periphery of the compressed parts 51, and as a result, the density increases as it approaches the compressed parts 51. The non-compressed parts 52 only need to be thicker and have a lower density than the compressed parts 51, and the entire part can be compressed in the thickness direction at the same time, before, or after the compressed parts 51 are formed. The shape and arrangement of the non-compressed portion 52 are determined according to the shape and arrangement of the compressed portion 51 , and may be in a staggered shape, a mesh shape, a grid shape, a stripe shape, or the like.

[0136] The absorbent member having such a compressed portion 51 and a non-compressed portion 52 can be manufactured by a known method such as embossing. For example, the absorbent member 50 having the compressed portion 51 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 aggregated; a second step of forming a package in which the absorbent body 56 is packaged with a packaging sheet 58; and a third step of forming a package in which the absorbent body 56 is packaged with a packaging sheet 58. Fig. 22 As shown, the package 50P is passed between a support roller 90 and a smooth roller 92, the support roller 90 having a plurality of protrusions 91 arranged at intervals in the same pattern as the compression portion 51 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 compression portion 51 is formed by pressing a portion of the package 50P sandwiched between the plurality of protrusions 91 of the support roller 90 and the smooth roller 92. The compression portion 51 may be formed while heating either or both of the support roller 90 and the smooth roller 92, or may be formed 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 portion sandwiched between the multiple protrusions 91 of the support roller 90 and the smooth roller 92 may be pressed to the deepest extent while pressing the entire package 50P.

[0137] The thickness 50t of the absorbing member 50 and the thickness 51t of the compressed portion 51 can be appropriately determined. 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 4 to 35 mm, and particularly preferably 5 to 13 mm. The thickness 51t of the compressed portion 51 can be appropriately determined. Generally, it is preferably 15 to 35% of the maximum value of the thickness 50t of the absorbing member 50.

[0138] The compression parts 51 may be arranged in a regular or irregular pattern. For example, the pattern of the compression parts 51 may be as follows: Fig.10 and Fig.11 As shown, the continuous linear compression portion 51 is formed into a grid-like pattern; Fig.16 The compression portion 51 arranged in a dotted line is formed into a lattice pattern as shown in (b); although not shown, the compression portion 51 arranged in a continuous line or dotted line is formed into a stripe pattern (vertical stripe, horizontal stripe, etc.); or Fig.16 As shown in (a), the dot-shaped compression parts 51 are arranged in a row or staggered pattern.

[0139] A preferred pattern of the compression portion 51 is Fig.10 and Fig.11 As shown in the example, the first part 51a extends in a direction inclined 40 to 50 degrees clockwise relative to the front-to-back direction LD when viewed from above, and the second part 51b extends in a direction inclined 40 to 50 degrees counterclockwise relative to the front-to-back 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 width direction WD of the unit frame 51f can be about 15 to 20 mm. In addition, the size 51y of the unit frame 51f in the front-to-back direction LD can be about 15 to 20 mm.

[0140] When the compressed portion 51 is formed in a linear or dotted line shape, the width 51w of the compressed portion 51 (the width of the bottom of the recess formed in the absorbing member 50) can be appropriately determined, and is usually preferably about 1 to 3 mm. In addition, when the compressed portion 51 is formed in a dotted shape, the maximum diameter (the maximum diameter of the bottom of the recess formed in the absorbing member 50) can be appropriately determined, and is usually preferably about 1 to 3 mm.

[0141] The area ratio of the compressed portion 51 (the bottom of the concave portion) on the back surface of the absorbing member 50 can be appropriately determined. However, if the compressed portions 51 are arranged too densely, the absorbing member 50 becomes hard, so it is preferably about 10 to 14%.

[0142] In addition, the compression part 51 may be provided only on a part of the back surface of the absorbing member 50 in addition to being provided over the entire back surface of the absorbing member 50. Fig.16 As shown in (a), a preferred embodiment is to provide the compression part 51 only in the middle region 50M in the front-to-back direction LD including the crotch portion M, and not to provide the compression part 51 in the front region 50F and the rear region 50B. When the middle region 50M of the absorbent member 50 is sandwiched between the legs, it is subjected to forces in various directions from both sides in the width direction WD due to the movement of the legs such as walking, so it is preferred to improve the shape retention by the compression part 51, and it is preferred that the other regions do not have the compression part 51, thereby improving the anti-escape property of the superabsorbent polymer particles.

[0143] In addition, if the absorbent member 50 is firmly fixed to the member adjacent to the back side (the liquid-impermeable sheet 11 in the example shown in the figure) up to the vicinity of the two side edges, the two side portions of the absorbent member 50 are less likely to deform, and as a result, the superabsorbent polymer particles are less likely to fall out at the two side portions, which is preferred. Fig.16 As shown in the example of (a), no compression portion 51 is provided near the two side edges of the absorption member 50 (for example, about 5 to 10 mm in the width direction WD), so that the two side edges of the joining area 50HM between the absorption member 50 and the component adjacent to its back side (the liquid-impermeable sheet 11 in the example shown in the figure) are located between the two side edges of the absorption member 50 and the compression portion 51 closest to it.

[0144] In addition, if Figure 5 , Fig.17 and Fig.18As shown, when the back side of the absorbent member 50 is bonded to the liquid-impermeable sheet 11 by means of the hot melt adhesive HM, and the liquid-impermeable sheet 11 extends from a position further forward than the front edge of the absorbent member 50 to a position further backward than the rear edge of the absorbent member 50, and from a position further left than the left edge of the absorbent member 50 to a position further right than the right edge of the absorbent member 50, it is preferred that the hot melt adhesive HM is applied from a position further forward than the front edge of the absorbent body 56 to a position further backward than the rear edge of the absorbent body 56, and from between the left edge of the absorbent body 56 and the left edge of the absorbent member 50 to between the right edge of the absorbent body 56 and the right edge of the absorbent member 50. Thus, it is possible to suppress the reduction in the softness of both side edges of the absorbent member, and to effectively suppress the superabsorbent polymer particles from coming out of the back side of the absorbent member. The hot melt adhesive HM only needs to be applied from a position forward of the front edge of the absorbent body 56 to a position backward of the rear edge of the absorbent body 56. It can be applied from a position between the front edge of the absorbent body 56 and the front edge of the absorption member 50 to a position between the rear edge of the absorbent body 56 and the rear edge of the absorption member 50, or it can be applied from a position forward of the front edge of the absorption member 50 to a position backward of the rear edge of the absorption member 50.

[0145] (Packaging non-woven fabric)

[0146] The packaging nonwoven fabric 58 preferably has a meltblown layer formed of fibers having an average fiber diameter of 5 μm or less, and has an air permeability of 25.5 to 70.0 cm2 by the A method (Frazier method) measured in accordance with JIS L 1096:2010 when five sheets are stacked. 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. The air permeability can be measured, for example, using an air permeability meter (model AP-500KZ4) of Daiei Kagaku Seiki Manufacturing Co., Ltd. As is well known, the meltblown layer is a nonwoven fabric layer formed by aggregating ultrafine fibers spun from a molten resin raw material in a high-speed hot air flow and bonding the fibers together. The average fiber diameter of the constituent fibers is as thin as 10 μm or less, the fiber length is 30 μm or more, and the fiber spacing is also small. The average fiber diameter of the fibers of the meltblown layer is preferably 2.5 μm or less. In addition, the average fiber diameter of the fibers of the meltblown layer can be 1 μm or more, preferably 2 μm or more.

[0147] 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 0.3 to 6 g / m2 The total thickness of the meltblown layer can be 0.01 to 0.35 mm.

[0148] By using such a nonwoven fabric having a dense meltblown layer, the problems (such as damage during manufacturing or use) when using crepe paper can be solved. In combination, as described above, by providing the compression portion 51 that is recessed from the back of the absorbent member 50 into the absorbent body 56, the shape maintenance of the absorbent body 56 can be improved. Moreover, by not providing the compression portion 51 that is recessed from the surface of the absorbent member 50 into the absorbent body 56, even when using a packaging nonwoven fabric 58 of the minimum necessary thickness, the fiber gaps in the portion (surface portion) of the packaging nonwoven fabric 58 that covers the surface of the absorbent member 50 will not be widened, and the state in which the superabsorbent polymer particles contained in the absorbent body 56 are not easily released through the surface portion of the packaging sheet can be maintained. Therefore, the compression portion 51 is provided in the same way as before to improve the shape maintenance of the absorbent body 56, and the release of the superabsorbent polymer particles that becomes a problem at this time can also be effectively suppressed.

[0149] The packaging nonwoven fabric 58 only needs to have a meltblown layer, and may be a single-layer nonwoven fabric consisting only of a meltblown layer, but is preferably a laminated nonwoven fabric having one or more meltblown layers and one or more protective layers. The laminated nonwoven fabric may be manufactured by sequentially overlapping the webs constituting each layer, and then bonding the fibers and the layers by thermal bonding (point bonding, hot air bonding, etc.), or by overlapping the nonwoven fabric layers constituting each layer (web formation and fiber bonding) and bonding the layers by heat or an adhesive.

[0150] As a protective layer, a spunbond layer can be appropriately used. As is known to all, a spunbond layer is a nonwoven fabric layer formed by aggregating 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 larger 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., in which at least one meltblown layer is sandwiched by a pair of spunbond layers on the front and back, 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 in the meltblown layer, and polypropylene fibers, polyethylene / polypropylene bicomponent fibers, etc. can be used in the spunbond layer.

[0151] 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 preferably have an average fiber diameter of 10 to 25 μm (particularly 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 (especially 5-10g / m 2 ), the total thickness of the protective layer is preferably 0.01 to 0.35 mm (especially 0.1 to 0.2 mm).

[0152] 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 15 g / m 2 (especially 10-13g / m 2 ) In addition, the thickness of the packaging nonwoven fabric 58 is preferably 0.2 to 0.8 mm.

[0153] If the wrapping nonwoven fabric 58 is not easily stretched, it is not only difficult to form a firm compression portion 51 (i.e., it is difficult to improve the shape retention), but also the softness of the absorbent body 56 is reduced. Therefore, it is preferred that the wrapping nonwoven fabric 58 has an elongation of 20 to 100%, particularly 30 to 60%, in the front-back direction LD according to the standard specified in JIS L1913:2010, and an elongation of 20 to 110%, particularly 50 to 70% in the width direction WD according to the standard specified in JIS L1913:2010. In such a nonwoven fabric, the fiber gaps are likely to increase due to the formation of the compression portion 51, but by having the above-mentioned characteristic structure such as the compression portion 51, it is possible to achieve both the improvement of the shape retention and softness of the absorbent body 56 and the suppression of the escape of the superabsorbent polymer particles.

[0154] The packaging structure of the packaging non-woven fabric 58 can be appropriately determined. From the perspectives of ease of manufacturing and preventing leakage of highly absorbent polymer particles from the front and rear edges, it is preferably wound into a cylindrical shape as shown in the example shown in the figure in a manner that surrounds the surface, back and two side surfaces of the absorbent body 56 and the front and rear edges thereof extend from the front and rear of the absorbent body 56, and the overlapping portions of the winding and the overlapping portions of the front and rear extending portions are joined by hot-melt adhesives, material welding or other joining means.

[0155] Especially if Fig.15As shown, if the packaging nonwoven fabric 58 has: a surface portion 58s, which is located on the surface side of the absorbent body 56; a first back portion 58a, which is a portion continuous from the surface portion 58s, bypassing one side edge of the absorbent body 56 and reaching the back side of the absorbent body 56; and a second back portion 58b, which is a portion continuous from the surface portion 58s, bypassing the other side edge of the absorbent body 56 and reaching the back side of the absorbent body 56, the first back portion 58a and the second back portion 58b have overlapping stacked portions 58W, and the compression portion 51 is entirely formed in the stacked portions 58W, then it is also possible to suppress the escape of highly absorbent polymer particles from the back side of the absorbent member 50, and is therefore preferred.

[0156] The shape maintenance of the compression part 51 on the absorbent member 50 depends on the maintenance of the compression part 51 itself, and the maintenance of the compression part 51 itself depends on the bonding strength between the packaging nonwoven fabric 58 and the absorbent body 56 in the compression part 51 and the shape maintenance of the absorbent body 56 itself. In addition, when the packaging nonwoven fabric 58 and the absorbent body 56 are bonded by hot melt adhesives HM1 and HM2, as the surface area increases due to the formation of the compression part 51, more hot melt adhesives HM1 and HM2 than usual are required to fully maintain the bonding strength between the packaging nonwoven fabric 58 and the absorbent body 56 and the shape maintenance of the absorbent body 56 itself. Therefore, it is preferred that the back surface of the absorbent body 56 and the inner surface of the packaging nonwoven fabric 58 be bonded by 5.0 to 20.0 g / m 2 , especially 7.5 to 15.0 g / m 2 The hot melt adhesives HM1 and HM2 are used for bonding.

[0157] For example, in Fig. 9 When a depression caused by the compressed portion 51 is formed on the back of the absorbent body 56 as shown in FIG. 1 , the above-mentioned amount of hot melt adhesive HM can be achieved by providing two layers of hot melt adhesive HM1 and HM2 on the back of the absorbent body 56 over the entire area having the compressed portion 51. Such a structure can be manufactured as follows: Fig.13 As shown in FIG. 1 , after the first hot melt adhesive HM1 is applied to substantially the entire surface of the inner surface of the unfolded packaging nonwoven fabric 58 that faces the absorbent body 56, the absorbent body 56 is arranged in the middle portion of the first hot melt adhesive HM1 in the width direction WD on the packaging nonwoven fabric 58, and the surface of the absorbent body 56 and the packaging nonwoven fabric 58 are bonded to each other by means of the first hot melt adhesive HM1. Then, after the second hot melt adhesive HM2 is applied to substantially the entire back surface of the absorbent body 56, as shown in FIG. Fig.14As shown in FIG. 1 , the portions of the packaging nonwoven fabric 58 extending toward the two sides of the absorbent body 56 are folded back onto the back side of the absorbent body 56, and the back side of the absorbent body 56 is bonded to the folded back portions of the packaging nonwoven fabric 58 by means of the first hot melt adhesive HM1 and the second hot melt adhesive HM2, and the overlapping portions of the packaging nonwoven fabric 58 are bonded by means of the first hot melt adhesive HM1, and then as shown in FIG. Fig. 9 As shown, a lattice-shaped compressed portion 51 is formed by embossing.

[0158] To reduce costs, the absorbent member 50 may be Fig. 9 As shown in the examples above, there is no other layer such as paper or nonwoven fabric between the packaging nonwoven fabric 58 and the absorbent body 56 (of course, an adhesive layer may be provided), or there may be other layers on at least one side of the front and back of the absorbent body 56. For example, it is known that the compressed portion 51 of the absorbent member 50 has a stronger ability to absorb liquid and has a higher liquid retention than the non-compressed portion 52. Therefore, in order to prevent backseepage or a wet feeling when worn, it is preferred that the compressed portion 51 is away from the skin. However, the compressed portion 51 of this example is a portion compressed in the thickness direction in a manner that is recessed from the back side of the absorbent member 50 into the absorbent body 56. Therefore, it is closer to the wearer's skin than the compressed portion 51 that is formed in the opposite direction to the front and back. In particular, in a structure where the absorbent member 50 is not covered and the packaging nonwoven fabric 58 is exposed on the surface of the diaper as described later, the compressed portion 51 is closer to the skin. Therefore, as Fig. 20 As shown, an anti-repermeation layer 57 may also be provided between the surface of the absorbent body 56 (the surface on the skin side) and the back surface (the surface on the non-skin side) of the packaging nonwoven fabric 58. The anti-repermeation layer 57 may preferably use a hydrophobic or hydrophilic nonwoven fabric having a lower density than the absorbent body 56. The thickness of the anti-repermeation layer 57 may be appropriately determined, and may normally be about 0.1 to 1.2 mm. The anti-repermeation layer 57 shown in the figure is shorter than the width of the absorbent body 56 and is arranged in the center, but may also be provided over the entire width of the absorbent body 56. The configuration of the anti-repermeation layer 57 in the front-to-back direction LD may also be appropriately determined, and may be configured over the entire length of the absorbent body 56 or the entire length of the absorption member 50, or may be configured only in the middle of the front-to-back direction LD including the crotch portion M.

[0159] (Stand-up pleats)

[0160] The standing gathers 60 have a standing portion 68 standing up from the side of the inner body 200, and the standing portion 68 contacts the range from the wearer's groin through the leg circumference to the buttocks to prevent side leakage. The root side portion 60B of the standing gathers 60 shown in the figure stands up obliquely toward the center side in the width direction, and the front end side portion 60A stands up obliquely toward the outside in the width direction compared to the middle part, but it is not limited to this, and appropriate changes such as standing up toward the center side in the width direction as a whole can also be made.

[0161] To explain in more detail, the standing gather portion 60 shown in the figure is formed by folding a band-shaped gather sheet 62 having a length equal to the length of the inner body 200 in the front-back direction in two pieces by folding it back in the width direction WD at the front end portion, and fixing a plurality of elongated gather elastic members 63 at intervals in the width direction WD in a state of being stretched in the longitudinal direction between the folded portion and the adjacent sheets. The base end portion (the end portion on the opposite side of the sheet folded back portion in the width direction WD) of the standing gather portion 60 on the opposite side of the front end 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 front end side portion 60A folded back at the front end of the root side portion 60B and extending toward the outside in the width direction. Furthermore, the two end portions in the front-to-back direction of the main body portion 66 become inverted portions 67 fixed to the side 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 becomes a non-fixed standing portion 68, and a pleated elastic component 63 is fixed in an extended state along the front-to-back direction LD to at least the front end portion of the standing portion 68.

[0162] In the raised gather section 60 constructed as above, the raised portion 68 is contracted by the contraction force of the gather elastic member 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 raised portion 68 is raised in a manner that opens outward in the width direction in the crotch and its vicinity, so that the raised pleat portion 60 is in surface contact with the leg circumference, thereby improving the fit. The root portion 65 may also be fixed to the surface side of the inner body 200, for example, the surface of both sides of the top sheet 30.

[0163] In the curved structure that the main body 66 is composed of the root side portion 60B extending to the central side in the width direction and the front end portion 60A folded back at the front end of the root side portion 60B and extending outside in the width direction, in the prostrate portion 67, the front end portion 60A is engaged with the root side portion 60B in a prostrate state, and the root side portion 60B is engaged with the top sheet 30 in a prostrate state. The engagement of the opposite surface of the prostrate portion 67 can use at least one of the means based on material welding such as hot melt adhesives based on various coating methods and heat sealing or ultrasonic sealing. In this case, the engagement of the root side portion 60B and the top sheet 30 and the engagement of the front end portion 60A and the root side portion 60B can be carried out by the same means, or by different means. For example, it is preferred to utilize hot melt adhesives to carry out the engagement of the root side portion 60B and the top sheet 30, and utilize material welding to carry out the engagement of the front end portion 60A and the root side portion 60B.

[0164] As the pleated sheet 62, a material obtained by water-repellent treatment of soft, uniform, and shielding nonwoven fabrics such as spunbond nonwoven fabrics (SS, SSS, etc.), SMS nonwoven fabrics (SMS, SSMMS, etc.), and meltblown nonwoven fabrics 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 10 to 30 g / m 2 In addition, although not shown in the figure, a waterproof membrane may be interposed between the pleated sheets 62 folded into two pieces.

[0165] As the pleated elastic component 63, a rubber thread or the like can be used. When a spandex rubber thread is used, 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%. The number of pleated elastic components 63 is preferably 2 to 6, and more preferably 3 to 5. It is appropriate that the configuration interval of the pleated elastic component 63 is 3 to 10 mm. If so configured, it is easy to contact the skin with the surface within the range where the pleated elastic component 63 is configured. The pleated elastic component 63 can also be configured not only on the front end side but also on the root side.

[0166] In the rising portion 68 of the rising pleat portion 60, the inner layer and the outer layer of the pleat sheet 62 are bonded together, and the pleat elastic member 63 sandwiched therebetween is fixed by at least one of hot melt adhesives based on various coating methods and fixing means based on material fusion such as heat sealing or ultrasonic sealing. If the entire surface of the inner layer and the outer layer of the pleat sheet 62 are bonded together, the flexibility will be impaired, so it is preferred that the portion other than the bonding portion of the pleat elastic member 63 is not bonded or is weakly bonded. In the example shown in the figure, the following structure is formed: a hot-melt adhesive is applied only to the outer peripheral surface of the pleated elastic component 63 using a coating means such as a coating gun or a SureWrap nozzle and the component is sandwiched between the inner layer and the outer layer of the pleated sheet 62, thereby fixing the pleated elastic component 63 to the inner layer and the outer layer of the pleated sheet 62, and fixing the inner layer and the outer layer of the pleated sheet 62 to each other using only the hot-melt adhesive applied to the outer peripheral surface of the pleated elastic component 63.

[0167] Similarly, for fixing the collapsed portion 67, at least one of a hot melt adhesive by various coating methods and a material welding method such as heat sealing or ultrasonic sealing may be used.

[0168] (flank)

[0169] like Figure 1 to Figure 4As shown in the figures, it is preferred that side flaps 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 in the side flaps 70. The side flaps 70 shown in the figure have: one or more elongated side elastic members 73 arranged at intervals along the front-back direction LD; a first sheet layer 71 facing the outside of the side elastic members 73; and a second sheet layer 72 facing the inside of the side elastic members 73.

[0170] 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 above-mentioned standing pleated portion 60 and the above-mentioned outer body 12F, 12B can be selected. In the example shown in the figure, the pleated sheet 62 of the standing pleated portion 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 are consistent with the front and rear ends of the standing pleated portion 60 (that is, the front and rear ends of the inner body 200 in this case).

[0171] The side elastic members 73 are not particularly limited, and the same elongated elastic members as the above-mentioned gather elastic members 63 can be used. The elongation of the side elastic members 73 in the installed 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 to 10 mm.

[0172] The side elastic component 73 is fixed to the first sheet 71 and the second sheet 72. The first sheet 71 and the second sheet 72 are attached, and the side elastic component 73 sandwiched therebetween can be fixed by fixing means based on material welding, such as hot melt adhesive HM, heat sealing or ultrasonic sealing based on various coating methods. If the bonding area of ​​the first sheet 71 and the second sheet 72 is large, the flexibility is impaired, so the part other than the bonding part of the side elastic component 73 is preferably not bonded or weakly bonded. In the example of the figure, the following structure is formed: the hot melt adhesive HM is applied only on the peripheral surface of the side elastic component 73 by coating means such as a coating gun or a SureWrap nozzle and it is sandwiched between the first sheet 71 and the second sheet 72, thereby only using the hot melt adhesive HM coated on the peripheral surface of the side elastic component 73 to fix the side elastic component 73 to the first sheet 71 and the second sheet 72, and the first sheet 71 and the second sheet 72 are fixed.

[0173] 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-shaped closure) of the liquid-impermeable sheet 11. This fixing may be performed by welding the materials in addition to using the hot melt adhesive HM as in the example shown in the figure.

[0174] The side wings 70 may also be omitted.

[0175] (outer body)

[0176] The outer body 12F, 12B is composed of a rectangular front outer body 12F and a rectangular rear outer body 12B as shown in the example in the figure. The front outer body 12F is the part of the front body F that at least constitutes the waistline, and the rear outer body 12B is the part of the rear body B that at least constitutes the waistline. The front outer body 12F and the rear outer body 12B can be discontinuous on the crotch side and separated in the front-to-back direction LD (external two-part type), although not shown, but can also be continuous from the front body to the rear body (external one-piece type). The spacing distance 12d in the front-to-back direction of the outer two-part type can 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 can also be curved along the leg circumference.

[0177] In the two-part outer shorts-type disposable diaper, the inner body 200 is exposed between the front outer body 12F and the rear outer body 12B. Therefore, in order to prevent the liquid-impermeable sheet 11 from being exposed on the back of the inner body 200, it is preferred to have a cover nonwoven fabric 13 on the back of the inner body 200 from between the front outer body 12F and the inner body 200 to between the rear outer body 12B and the inner body 200. The inner surface and the outer surface of the cover nonwoven fabric 13 can be bonded to the opposite surface by means of a hot-melt adhesive, respectively. The nonwoven fabric used in the cover nonwoven fabric 13 can be appropriately selected from the same material as the outer body 12F and 12B. In addition, although not shown in the figure, the outer body can also be continuous from the front body part F through the crotch to the back body part B. 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.

[0178] 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 dimensions of the front and rear exterior bodies 12F and 12B in the front-rear direction LD are equal, and the front and rear exterior bodies 12F and 12B do not have a portion corresponding to the middle area L, but may also be as follows. Figure 7 As shown, the dimension of the rear outer body 12B in the front-to-back direction is longer than that of the front outer body 12F, and the front outer body 12F does not have a portion corresponding to the middle region L, but the rear outer body 12B has 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 be provided in the front outer body 12F.

[0179] like Figure 4 and Figure 5 As shown, the outer body 12F, 12B is formed by joining the outer side and inner side of the elastic components 16 to 19 described later with the outer side layer and the inner side layer adjacent to each other by means of hot melt adhesive, welding, etc. The outer side layer and the inner side layer can be formed by a single sheet material in addition to being formed by two sheets 12S, 12H as shown in the example in the figure. For example, in the latter case, the inner side layer and the outer side layer are formed by the inner side part and the outer side part of a sheet material folded back at the edge of the waist opening WO (which can also be the edge of the crotch side) in part or all of the outer body 12F, 12B. The example in the figure is an example of the former, and the sheet 12S forming the outer side layer of the lower waist part bypasses the waist opening WO side of the sheet 12H forming the inner side layer of the lower waist part and folds back to the inside thereof, and the folded part 12r extends in a manner 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.

[0180] In order to improve the fit to the wearer's waist, elastic components 16 to 19 are built into the outer bodies 12F and 12B to form 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 this elastic region A2, the outer bodies 12F and 12B contract in the natural length state as the elastic components contract, forming wrinkles or folds, and when stretched in the length direction of the elastic components, they can be stretched to a specified elongation without wrinkles and fully stretched. 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 special limitations. As elastic components 16 to 19, synthetic rubber or natural rubber can be used.

[0181] The elastic components 16 to 19 shown in the figure are described in more detail. In the waist portion W of the outer body 12F, 12B, a plurality of waist elastic components 17 are installed at intervals in the front-to-back direction in a continuous manner throughout the entire width direction WD. In addition, one or more 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 arranged on both sides in the width direction thereof in addition to 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 155 to 1880 dtex, particularly about 470 to 1240 dtex (in the case of synthetic rubber; in the case of natural rubber, a cross-sectional area of ​​0.05 to 1.5 mm 2 , especially 0.1~1.0mm 2The 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 in the width direction WD of the waist W is preferably 150 to 400%, especially about 220 to 320%. In addition, the waist W does not need to use elastic members of the same thickness or the same elongation in the entire front-to-back direction LD, and for example, the thickness or elongation may be different in a part.

[0182] In addition, a plurality of waist elastic members 16 and 19 composed of elongated elastic members are installed at intervals in the front-to-back direction in the waist lower portion U of the outer body 12F and 12B to form a waist lower stretchable area (an area having waist lower elastic members 16 and 19). As waist lower elastic members 16 and 19, preferably, the thickness is 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 2 , especially 0.1~1.0mm 2 The elastic cords (about 5 to 30) are arranged at intervals of 1 to 15 mm, especially 3 to 8 mm, and the elongation of the lower waist portion U in the width direction WD is preferably 200 to 350%, especially 240 to 300%. In addition, the lower waist portion U does not need to use elastic components of the same thickness or the same elongation in the entire front-to-back direction LD, and the thickness or elongation may be different in a part.

[0183] 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 of the figure, in order to prevent the absorbent body 56 from shrinking in the width direction WD in part or all of the absorbent body 56, as shown in the figure, Figure 4 , Figure 5 and Fig.12 As shown in the figure, it is preferred that the middle in the width direction including a part or all of the portion overlapping with the absorber 56 in the width direction WD is the non-elastic region A1, and the two sides in the width direction are the elastic regions A2 (the waist-lower elastic regions in the example shown in the figure). The width direction dimensions of the elastic regions A2 provided on the two sides in the width direction of the non-elastic region A1 are substantially constant in the front-back direction LD as shown in the example shown in the figure, but although not shown in the figure, they may also vary in the front-back direction LD. In addition, the width direction WD dimensions 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.

[0184] Such a stretchable region A2 and a non-stretchable region A1 can be constructed by installing elastic components 16 to 17, 19 between the inner sheet and the outer sheet, and then applying pressure and heating to the elastic components 16, 19 at one point in the middle of the width direction of the region to be the non-stretchable region A1 or substantially over the entire region, or by cutting the elastic components 16, 19 into thin pieces, so that the stretchability is retained in the stretchable region A2 while the stretchability is eliminated in the non-stretchable region A1. It should be noted that an unnecessary elastic component 18 that does not substantially contribute to the formation of stretchability will remain in the non-stretchable region A1.

[0185] The sheets 12S and 12H forming the inner sheet layer and the outer sheet layer may 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.

[0186] The elastic components 16 to 19 can be fixed to the outer body 12F, 12B by a known method. In addition, the inner sheet layer and the outer sheet layer 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 to the outer peripheral surface of the elastic components 16 to 19 by a coating means such as a coating gun or a SureWrap nozzle and sandwiched between the inner sheet layer and the outer sheet layer, thereby only using the hot melt adhesive HM applied to the outer peripheral surface of the elastic components 16 to 19 to fix the elastic components 16 to 19 to the inner sheet layer and the outer sheet layer, and the inner sheet layer and the outer sheet layer can be fixed.

[0187] (Inner body joint)

[0188] The inner body 200 can be joined to the outer body 12F, 12B by means of 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 means of a hot melt adhesive applied to the back surface of the inner body 200 (i.e., the back surface of the liquid-impermeable sheet 11 and the root portion 65 of the standing pleat portion 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 inner body 200 is provided in substantially the entire overlapping region, but may be provided in a portion other than both end portions in the width direction of the inner body 200, for example.

[0189] Since the escape of the superabsorbent polymer particles passing through the packaging nonwoven fabric 58 can be suppressed as described above, Fig.17 and Fig.18As shown, the top sheet 30 and the intermediate sheet 40 covering the surface of the absorption member 50 can be omitted, and in this case, a significant reduction in cost can be achieved. In this case, as long as the middle part of the surface of the absorption member 50 except the two end parts in the width direction WD is not covered by other parts in the entire front-back direction LD, and the packaging nonwoven fabric 58 is exposed on the surface, only the middle part in the width direction WD may not be covered by other parts as shown in the example, or the entire surface of the absorption member 50 may not be covered by other parts.

[0190] <Effect confirmation test>

[0191] like Fig.17 and Fig.18 As shown, 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 increased, and in addition, a film having the same Figure 1 to Figure 6 The shorts-type disposable diaper samples 1 to 8 have the same structure as shown. Other specifications are shown in Table 1. In addition, the specifications other than those shown in Table 1 are common to each sample.

[0192] Fig. 22 The test device 80 is shown in FIG. The test device 80 is constructed as follows: a recovery tray 83 for receiving the superabsorbent polymer is fixed on a vibration table 82b of a vibrator 82 (MK161 manufactured by Yamato Science Co., Ltd.) set on a horizontal plane 81, and a friction body 84 composed of a metal cylinder (diameter 55 mm) is vertically fixed in the center of the recovery tray 83, so that the recovery tray 83 and the friction body 84 and the vibration table 82b vibrate integrally. 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 bases 85 are vertically fixed on both lateral sides of the vibrator 82 on the horizontal plane 81. The sample 86 is made into an unfolded state (such as Figure 1 As shown), the sample 86 is stretched between the bases 85 with the surface (the exposed surface of the packaging nonwoven fabric) facing downward, and fixed on the base 85. At this time, the front-to-back direction LD of the sample 86 is made to be the major axis direction BD of the ellipse in the vibration mode. In addition, the distance d2 in the vertical direction between the friction body contact portion of the surface of the sample 86 without the friction body 84 and the upper surface of the vibration table 82b is set to 71 mm, so that the surface of the sample 86 is in contact with the friction body 84. 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.23 As shown, the friction body 84 is made to move elliptically and rub against the surface of the sample 86, and then the number of superabsorbent polymer particles falling onto the recovery tray 83 is counted.

[0193] The test results are shown in Table 1. Samples 1, 3, and 5 had superabsorbent polymer particles escaping, but samples 2, 4, and 6 had no superabsorbent polymer particles escaping despite the high air permeability of the packaging nonwoven fabric. Samples 7 and 8 had high weight per unit area of ​​the packaging nonwoven fabric and low air permeability, so no superabsorbent polymer particles escaping.

[0194]

[0195] <Explanation of terms in the specification>

[0196] Unless otherwise specified in the specification, the following terms in the specification have the following meanings.

[0197] 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 is orthogonal to the width direction.

[0198] The “front side” refers to the side close to the wearer's skin when worn, and the “back side” refers to the side away from the wearer's skin when worn.

[0199] The “front surface” refers to the side close to the wearer's skin when worn, and the “rear surface” refers to the side away from the wearer's skin when worn.

[0200] "Elongation" means a value when the natural length is 100%. For example, an elongation of 200% has the same meaning as an elongation of 2 times.

[0201] "Artificial urine" refers to 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.

[0202] "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).

[0203] The “average fiber diameter” is determined by observing the target layer at 1000-fold magnification using a microscope (optical microscope, SEM, etc.), randomly selecting 30 constituent fibers, measuring the fiber diameters (μm), and calculating the average value.

[0204] ·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 allow it to reach a constant weight. Pre-drying means allowing the sample or test piece to reach a constant weight in an environment with a temperature of 100°C. It should be noted that pre-drying is not required for fibers with an official moisture regain of 0.0%. Use a template (100mm×100mm) for sample collection to cut a sample of 100mm×100mm in size from the test piece that has reached a constant weight. Measure the weight of the sample and multiply it by 100 to calculate the weight per 1 square meter as the weight per unit area.

[0205] The "thickness" of thick parts such as the absorbent body 56, the absorbing member 50, and the compression part 51 is measured using a thickness gauge (Peacock, dial-type thickness gauge, model JB (measuring range 0 to 35 mm, round 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., with the sample and the thickness gauge being horizontal.

[0206] The thickness of non-woven fabrics and other thin sheets is measured using an automatic thickness tester (KES-G5 portable compression measurement program) at a load of 0.098N / cm 2 And pressurized area: 2cm 2 It should be noted that the "thickness" of the packaging nonwoven fabric refers to the thickness of the portion where the thickness 50t of the absorbing member 50 is the maximum value.

[0207] The "layer thickness" of the nonwoven fabric is determined as follows: using a microscope (optical microscope or SEM, etc.), observing the cross section of the target layer at a magnification of 1000 times where the thickness 50t of the absorbent member 50 is the maximum, randomly selecting 5 measurement positions, measuring the apparent thickness, and calculating the average value.

[0208] The “area ratio” refers to the ratio of the area of ​​the target portion per unit area, and is a value obtained by dividing the total area occupied by the target portion (e.g., the compression portion 51) in the entire target region (e.g., the back surface of the absorbent member 50) by the area of ​​the target region and expressing it as a percentage.

[0209] The water absorption was measured in accordance with JIS K7223-1996 "Test method for water absorption of super absorbent resin".

[0210] 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.

[0211] The "expanded state" refers to a state in which the device is flatly expanded without any contraction (including any contraction such as contraction due to elastic members) or relaxation.

[0212] ・ Unless otherwise specified, the dimensions of each part refer to the dimensions in the unfolded state, not the natural length state.

[0213] If there is no description of the environmental conditions during the test or measurement, the test or measurement was carried out in a test room or device under standard conditions (temperature of the test site is 23±1°C and relative humidity is 50±2%).

[0214] Industrial Applicability

[0215] The present invention can be used in all absorbent articles such as disposable diapers such as pants-type disposable diapers, belt-type disposable diapers, and pad-type disposable diapers, and sanitary napkins.

[0216] Explanation of symbols

[0217] 11... liquid-impermeable sheet, 12A... side seal, 12B... rear outer body, 12E... waist extension portion, 12F, 12B... outer body, 12F... front outer body, 12S, 12H... sheet material, 13... cover nonwoven fabric, 16, 19... elastic components below the waist, 17... waist elastic components, 18... unnecessary elastic components, 20... inner body joint portion, 200... inner body, 30... top sheet, 40... middle sheet, 50... absorbent member, 51... compression portion, 51f... unit frame, 52... non-compression portion, 56... absorbent body, 56c... covering layer, 56L... low basis weight portion, 58... packaging nonwoven fabric, 60... standing pleat portion, 60A... front end Side portion, 60B…root side portion, 62…pleated sheet, 63…pleated elastic component, 67…falling portion, 68…standing portion, 70…side wing, 71…first sheet layer, 72…second sheet layer, 73…side elastic component, A1…non-stretchable area, A2…stretchable area, B…back body, C…hip cover, F…front body, HM…hot melt adhesive, L…middle area, LD…front and back direction, LO…leg opening, M…crotch, SG…side stretchable area, T…waist area, U…lower part of waist, W…waist, WD…width direction, WO…waist opening, HM1…first hot melt adhesive, HM2…second hot melt adhesive, 57…anti-rewet layer.

Claims

1. An absorbent article, characterized in that: The invention has a crotch portion, and a front side portion and a rear side portion extending from the crotch portion to the front side and the rear side, respectively. The invention is provided with an absorbing member including an absorbent body provided in a front-back direction range 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 aggregated. The packaging nonwoven fabric has a meltblown layer formed of fibers having an average fiber diameter of 5 μm or less, and has an air permeability of 25.5 cm by method A (Frazier method) measured in accordance with JIS L 1096:2010 when five sheets are stacked. 3 / cm 2 ·s~70.0cm 3 / cm 2 ·s non-woven fabric, The absorbing member is provided with compressed portions at intervals in the thickness direction so as to be recessed from the back surface of the absorbing member into the absorbent body, and The absorbent member is not provided with a compressed portion compressed in the thickness direction so as to be recessed from the surface of the absorbent member into the absorbent body.

2. The absorbent article according to claim 1, wherein The packaging nonwoven fabric has one or more meltblown layers and one or more protective layers. The protective layer is made of fibers with an average fiber diameter of 10 μm to 25 μm. The elongation of the packaging nonwoven fabric in the front-to-back direction according to the standard specified in JIS L 1913:2010 is 20% to 100%, The elongation in the width direction according to the standard specified in JIS L 1913:2010 is 20% to 110%.

3. The absorbent article according to claim 1 or 2, 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 compressed portion is 15% to 35% of the maximum value of the thickness of the absorbing member.

4. The absorbent article according to claim 3, wherein: The width of the compression portion is 1 mm to 3 mm. The compression portion is formed in an oblique lattice shape composed of a first portion inclined 40 to 50 degrees clockwise with respect to the front-rear direction in a plan view and a second portion inclined 40 to 50 degrees counterclockwise with respect to the front-rear direction in a plan view.

5. The absorbent article according to claim 1 or 2, wherein: The absorbent body has a covering layer composed only of accumulated pulp fibers, which covers the surface of the absorbent body.

6. The absorbent article according to claim 1 or 2, wherein: The packaging nonwoven fabric comprises: a surface portion, which is located on the surface side of the absorbent body; a first back side portion, which is a portion continuous from the surface portion, bypassing one side edge of the absorbent body and reaching the back side of the absorbent body; and a second back side portion which is a portion continuous from the surface portion, bypassing the other side edge of the absorbent body and reaching the back side of the absorbent body, The first back side portion and the second back side portion have a stacked portion that overlaps each other. The compressed portion is entirely formed in the laminated portion.

7. The absorbent article according to claim 1 or 2, wherein: The middle portion of the absorbent member except for both ends in the width direction is not covered by other members in the entire front-back direction, and the wrapping nonwoven fabric is exposed on the surface of the absorbent article.

8. The absorbent article according to claim 1 or 2, wherein: A liquid-impermeable sheet bonded to the back of the absorbent member by a hot-melt adhesive, The liquid-impermeable sheet extends from a position further forward than the front edge of the absorbent member to a position further rearward than the rear edge of the absorbent member, and extends from a position further to the left than the left edge of the absorbent member to a position further to the right than the right edge of the absorbent member. The hot melt adhesive is applied from a position forward of the front edge of the absorbent body to a position backward of the rear edge of the absorbent body, and from between the left edge of the absorbent body and the left edge of the absorbent member to between the right edge of the absorbent body and the right edge of the absorbent member.

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