Absorbent article

Abstract

A back sheet (10) of an absorbent article (1) of the present application has, in order from a skin-facing side to a non-skin-facing side, a first sheet (11), a second sheet (12), and a third sheet (13). The third sheet (13) forms a non-skin-facing side of the absorbent article (1). The absorbent article (1) has a first joining region (41) in which the first sheet (11) and the second sheet (12) are joined by an adhesive, and a second joining region (45) in which the second sheet (12) and the third sheet (13) are joined by an adhesive, the first joining region and the second joining region at least partially overlapping when viewed from above. The first joining region (41) and the second joining region (45) each have an adhesive-arranged portion (42, 46) in which the adhesive is arranged, and an adhesive-unarranged portion (43, 47) in which the adhesive is not arranged. The area ratio of the adhesive-arranged portion of the first joining region (41) is lower than that of the second joining region (45).

Description

Technical Field

[0001] This invention relates to absorbent articles. Background Technology

[0002] Disposable diapers and other absorbent articles typically comprise an absorbent body with an absorbent core and multiple sheets disposed on the non-skin-facing side relative to the absorbent body. For example, the applicant previously disclosed an absorbent article having an absorbent body and an outer body, wherein the absorbent body has a liquid-permeable front sheet, a liquid-leak-proof back sheet, and a liquid-retaining absorbent body in between, the outer body being located on the back sheet side of the absorbent body, and the back sheet and the outer body being bonded together by an adhesive applied in a striped pattern at intervals in the portions excluding the two side edges and the front and rear ends of the absorbent body along its length (Patent Document 1).

[0003] Furthermore, the applicant previously disclosed an absorbent article comprising an outer body disposed on the non-skin-facing side of an absorbent body, having an outer sheet, an inner sheet, an elastic member between the two sheets, and a strip adhesive disposed longitudinally at intervals along the transverse direction. In the stretchable region of the outer body, the elastic member is disposed longitudinally at intervals, and at each interval between adjacent elastic members in the longitudinal direction, one or more strip adhesives are disposed, wherein the outer sheet and the inner sheet are fixed together by the strip adhesives (Patent Document 2).

[0004] In addition, the applicant previously disclosed an absorbent article comprising an outer sheet, an inner sheet, a leg elastic member located between the two sheets, and an outer body for securing the leg adhesive, disposed on the non-skin-facing side of the absorbent body. In the unfolded state of the diaper, each leg adhesive is arranged laterally in the area where the longitudinal leg elastic member is disposed, and the longitudinally adjacent leg adhesives are spaced apart by two or more different intervals (Patent Document 3).

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: Japanese Patent Application Publication No. 2005-095261

[0008] Patent Document 2: Japanese Patent Application Publication No. 2016-022235

[0009] Patent Document 3: Japanese Patent Application Publication No. 2016-022236 Summary of the Invention

[0010] The present invention relates to an absorbent article having a front sheet, a back sheet and an absorbent core disposed between the front sheet and the back sheet, and having a longitudinal direction corresponding to the wearer's front-back direction and a transverse direction orthogonal to the longitudinal direction.

[0011] Preferably, the back sheet has a first sheet, a second sheet, and a third sheet sequentially from the skin-facing side to the non-skin-facing side.

[0012] Preferably, the third piece forms the non-skin-facing side of the absorbent article.

[0013] Preferably, the back sheet has a first bonding region where the first sheet and the second sheet are joined by an adhesive, and a second bonding region where the second sheet and the third sheet are joined by an adhesive, wherein the first bonding region and the second bonding region at least partially overlap when viewed from above.

[0014] Preferably, the first bonding region and the second bonding region each have an adhesive placement section with the adhesive disposed thereon and an adhesive non-placement section without the adhesive disposed thereon.

[0015] Preferably, the area ratio of the adhesive configuration portion in the first bonding region is lower than the area ratio of the adhesive configuration portion in the second bonding region. Attached Figure Description

[0016] Figure 1 This is a plan view showing the unfolded and elongated state of a disposable diaper as an embodiment of the present invention.

[0017] Figure 2 yes Figure 1 Section II-II view.

[0018] Figure 3 (a) is a plan view illustrating the location of the first joint region. Figure 3 (b) is a plan view used to illustrate the location of the second joint area.

[0019] Figure 4 yes Figure 3 The cross-sectional view of the overlapping area along the longitudinal direction is shown.

[0020] Figure 5 (a) and (b) are longitudinal cross-sectional views used to illustrate the effect of the overlapping area.

[0021] Figure 6 This is a plan view showing the coating pattern of the adhesive that forms the first and second bonding regions of the present invention. Detailed Implementation

[0022] Multiple sheets disposed on the non-skin-facing side of an absorbent article, relative to the absorbent body, are components that can affect the appearance and feel of the absorbent article. The outer surface of an absorbent article is mostly visually identifiable by the wearer or their protector, and it frequently comes into contact with the user's fingers when worn. Therefore, the outer surface of the absorbent article is required to have excellent tactile feel and a pleasant skin-touch experience. While the absorbent articles described in Patent Documents 1-3 consider softness and tactile feel on the outer surface, they do not further explore the consideration of both appearance and skin-touch experience.

[0023] This invention relates to absorbent articles that can achieve both a good appearance and a good feel against the skin.

[0024] Hereinafter, the present invention will be described with reference to the accompanying drawings and based on preferred embodiments thereof. Figure 1 and Figure 2 A shorts-type disposable diaper 1 (hereinafter simply referred to as "diaper 1") is shown as one embodiment of the absorbent article of the present invention. Diaper 1 has a ventral portion A disposed on the wearer's abdomen when worn, a dorsal portion B disposed on the wearer's back, and a crotch portion C located between the ventral portion A and the dorsal portion B. Diaper 1 has a longitudinal direction X corresponding to the wearer's front-back direction, i.e., the direction extending from the ventral portion A through the crotch portion C to the dorsal portion B, and a transverse direction Y orthogonal to the longitudinal direction X.

[0025] The diaper 1 has an absorbent core 22 in the central portion of the transverse Y direction, and includes a back panel 10 disposed on the non-skin-facing side of the absorbent core 22, i.e., the side farther from the wearer's body than the absorbent core 22 (see reference). Figure 2 ).

[0026] In this specification, "skin-facing side" refers to the side of the absorbent article or its constituent parts (e.g., front panel 21) that faces the wearer's skin when the absorbent article is worn, i.e., the side relatively closer to the wearer's skin. "Non-skin-facing side" refers to the opposite side of the absorbent article or its constituent parts that faces the skin when the absorbent article is worn, i.e., the side relatively farther from the wearer's skin. Furthermore, "when wearing" as used here refers to maintaining the usual, proper wearing position, i.e., the correct wearing position of the absorbent article.

[0027] like Figure 1 As shown, the diaper 1 is formed in an unfolded and stretched state, and is symmetrical about the longitudinal center line CL, which extends longitudinally X and bisects the diaper 1 transversely Y. Figure 1As shown, the absorbent body 22 is rectangular in shape when viewed from above, with its length direction aligned with the longitudinal direction X of the diaper 1 in its unfolded and extended state. When viewed from above, the absorbent body 22 is positioned at the center of the transverse direction Y of the outer body 3 (second piece 12 and third piece 13, described later) and is bonded to the backing sheet 10 with an adhesive.

[0028] The "unfolded and stretched state" of diaper 1 refers to the state in which diaper 1 is unfolded along the side seal S, allowing the elastic components of each part to stretch and expand the unfolded diaper 1 to the designed size (the same size as when it is expanded into a flat shape with the influence of the elastic components completely eliminated). In this specification, unless otherwise specified, the dimensions such as the longitudinal X or transverse Y length of each part of diaper 1 refer to the dimensions (design dimensions) of the state in which the elastic components of each part are stretched and the parts are flattened.

[0029] like Figure 2 As shown, the diaper 1 includes an absorbent body 2, which has a liquid-permeable front sheet 21, a leak-proof sheet 28, and a liquid-retaining absorbent body 22 disposed between the two sheets 21 and 28, as well as a pair of leak-proof flanges 26, 26. In the absorbent body 2, the front sheet 21, the absorbent body 22, the pair of leak-proof flanges 26, and the leak-proof sheet 28 are integrally formed by bonding them together using a known bonding method such as an adhesive. The absorbent body 2 is formed into a rectangular shape that is longer in the longitudinal direction X when viewed from above, extending from the ventral side A to the dorsal side B along the longitudinal direction X. In this embodiment, the positions of the two ends of the absorbent body 2 in the longitudinal direction X are approximately the same as the positions of the two ends of the absorbent body 22 in the longitudinal direction X. The leak-proof sheet 28 in this embodiment corresponds to the first sheet 11 described later.

[0030] The absorbent body 22 extends longitudinally between the ventral portion A and the dorsal portion B, and is composed of a liquid-retaining absorbent core 24 and a chip 25 that contacts and encapsulates its outer surface.

[0031] like Figure 2 As shown, the absorbent core 24 of this embodiment has a pair of side absorbent cores 24S, 24S and a pair of central absorbent cores 24C located between the pair of side absorbent cores 24S, 24S. The pair of side absorbent cores 24S, 24S and the central absorbent core 24C extend longitudinally X at the crotch C. Furthermore, the central absorbent core 24C has a double-layer structure, while the side absorbent cores 24S have a single-layer structure. The absorbent core 24 of this embodiment has a side bending guide 23S between the side absorbent cores 24S and the central absorbent core 24C, and also has a central bending guide 23C between the pair of central absorbent cores 24C. The absorbent body 22 can deform from the side bending guides 23S, 23S in such a way that the side absorbent cores 24S, 24S are lifted toward the wearer's skin (see reference). Figure 2Furthermore, the absorber 22 can be deformed by bending a pair of central absorbent cores 24C into a mountain-shaped fold (convex fold) starting from the central fold guide portion 23C (not shown).

[0032] In this embodiment, the side bending guide portions 23S, 23S and the central bending guide portion 23C in the absorbent body 22 are formed by a through hole extending in the longitudinal direction X and penetrating the absorbent core 24. Alternatively, the side bending guide portions 23S, 23S and the central bending guide portion 23C may be recesses formed on the skin-facing or non-skin-facing side of the absorbent core 24.

[0033] In this embodiment, the absorbent body 22 has core elastic members 31 arranged in an elongated state on both sides along the longitudinal direction X. The core elastic members 31 are arranged between the absorbent core 24 and the plywood 25 on both sides of the absorbent body 22 along the longitudinal direction X. By contracting the core elastic members 31 in the longitudinal direction X, the deformation of the side absorbent core 24S starting from the side bending guide portion 23S can be assisted. That is, the side absorbent core 24S is easily deformed in a way that it is lifted toward the wearer's skin.

[0034] like Figure 1 As shown, the absorbent body 2 has a pair of leak-proof flanges 26, 26 on both sides along the longitudinal X direction on its skin-facing side. (As shown...) Figure 2 As shown, the leak-proof flange 26 of this embodiment is formed by folding a leak-proof flange forming sheet 27 that is liquid-resistant, water-repellent, and breathable, and then joining two opposite leak-proof flange forming sheets 27 together. The leak-proof flange 26 of this embodiment has a flange elastic member 35 and an outer flange elastic member 32 between the two opposite leak-proof flange forming sheets 27. The flange elastic member 35 is disposed at the inner end of the transverse Y direction of the leak-proof flange 26, and the outer flange elastic member 32 is disposed at the outer end of the transverse Y direction of the leak-proof flange 26 (see reference). Figure 1 and Figure 2 These flange elastic members 35 and outer flange elastic members 32 are arranged in an extended state in the longitudinal direction X. Each leak-proof flange 26 has a base end fixed between the absorbent body 22 and the leak-proof sheet 28 in the absorbent body 2, and a free end fixed to the flange elastic member 35. The leak-proof flange 26 is configured such that the free end of the leak-proof flange 26 can stand up at least at the crotch C by the contraction of the flange elastic member 35 arranged in an extended state in the longitudinal direction X. In addition, the outer flange elastic member 32 assists in the standing up of the leak-proof flange 26 by contraction in the longitudinal direction X.

[0035] like Figure 2As shown, the back cover 10 has a first sheet 11, a second sheet 12, and a third sheet 13 sequentially from the skin-facing side to the non-skin-facing side. In other words, the back cover 10 has a third sheet 13, a second sheet 12, and a first sheet 11 sequentially from the non-skin-facing side of the diaper 1 to the skin-facing side. The non-skin-facing side of the diaper 1 is formed by the third sheet 13 of the back cover 10. In this way, the back cover 10 is positioned on the non-skin-facing side compared to the absorbent core 24, and the third sheet 13 forms the non-skin-facing side of the diaper 1. The first sheet 11 and the second sheet 12 are directly joined, and the second sheet 12 and the third sheet 13 are directly joined.

[0036] In this embodiment, the back sheet 10 is positioned on the non-skin-facing side compared to the absorbent body 22 (chip 25). The back sheet 10 of this embodiment has a first sheet 11 as a leak-proof sheet 28 forming the non-skin-facing side of the absorbent body 2. Furthermore, the back sheet 10 includes a second sheet 12 and a third sheet 13 positioned on the non-skin-facing side compared to the absorbent body 2. The constituent parts (the second sheet 12 and the third sheet 13) positioned on the non-skin-facing side compared to the absorbent body 2 are also referred to as the outer casing 3. In the outer casing 3, the second sheet 12 and the third sheet 13 have the same shape and size when viewed from above.

[0037] In this embodiment, the first sheet 11 (leak-proof sheet 28) is a moisture-permeable membrane, and the second sheet 12 and the third sheet 13 are fiber sheets formed of fibrous material.

[0038] exist Figure 2 The illustrations of the first adhesive preparation section 42 and the second adhesive preparation section 46, which will be described later, are omitted in the text.

[0039] In the outer body 3, the two side edges of the outer body 3 along the longitudinal direction X of the ventral side A and the dorsal side B are joined together by known joining methods such as hot melt adhesive, heat sealing, and ultrasonic sealing, thereby forming a pair of side seals S, S, a waist opening for the wearer's waist to pass through, and a pair of leg openings for the wearer's lower limbs to pass through (not shown).

[0040] External body 3 formation Figure 1 The outer body 3, in its unfolded and elongated state, forms the outline of the diaper 1, specifically the outlines of the ventral side A, crotch area C, and dorsal side B. Within the outer body 3, as shown... Figure 1As shown, the two sides of the longitudinal X of the outer body 3 are curved at the crotch C into an arc shape that bulges towards the center of the transverse Y, and the central region of the longitudinal X narrows inward towards the transverse Y. The outer body 3 and the absorbent body 2 are joined together by a known joining method such as an adhesive. In addition, at least one of the second piece 12 and the third piece 13 of the outer body 3 is folded back towards the skin-facing side along the peripheral edge WE of the waist opening.

[0041] In the outer body 3, the third piece 13 forms the outer surface of the diaper 1, i.e., the non-skin-facing side, and the second piece 12 is disposed on the skin-facing side of the third piece 13. The outer body 3 has a plurality of linear or strip-shaped elastic members 36, 37 disposed between the second piece 12 and the third piece 13. Specifically, the outer body 3 has a waist elastic member 36 disposed along the transverse Y direction on the ventral side A and the dorsal side B, and a leg elastic member 37 disposed along the leg opening (see reference). Figure 1 In this embodiment, the waist elastic member 36, positioned in the longitudinal direction X and overlapping with the absorbent body 2, is configured in the region overlapping with the absorbent body 2 in the thickness direction Z so that it does not exhibit elastic stretchability due to fine cutting or other processing. However, the waist elastic member 36 can still exhibit elastic stretchability in this region. In both the ventral portion A and the dorsal portion B, the waist elastic member 36 is spaced apart at predetermined intervals in the longitudinal direction X, elongated in the transverse direction Y. In this way, by configuring the waist elastic member 36 to exhibit its elastic stretchability, a substantially continuous annular waist fold (pleat) is formed at the opening edge of the waist opening, covering its entire circumference.

[0042] One or more linear or strip-shaped leg elastic members 37 for forming leg pleats are disposed in the outer body 3 in a telescoping state at the leg edge portion LS forming the leg opening. The leg elastic member 37 extends longitudinally X from a portion of the back side portion B, i.e., the central side of the longitudinal X, through the crotch C to a portion of the ventral side portion A, the central side of the longitudinal X (see reference). Figure 1 By arranging the leg elastic member 37 in an extended state, a substantially continuous annular leg fold is formed around the entire circumference of the opening edge (leg edge LS) of the leg opening. The leg elastic member 37 is also clamped and fixed between the third piece 13 and the second piece 12 constituting the outer body 3 by means of bonding such as adhesive.

[0043] In the back panel 10, adjacent first panels 11 and second panels 12, and second panels 12 and third panels 13 in the thickness direction Z of the diaper 1 are joined together by an adhesive. The diaper 1 has a first joining region 41 formed by the adhesive joining of the first panels 11 and the second panels 12, and a second joining region 45 formed by the adhesive joining of the second panels 12 and the third panels 13 [see reference]. Figure 3[of (a) and (b)].

[0044] In diaper 1, the absorbent body 2 and the outer body 3 are joined in the first joining region 41, and the sheets 12 and 13 constituting the outer body 3 and the leg elastic member 37 are joined in the second joining region 45.

[0045] The first bonding region 41 and the second bonding region 45 each have an adhesive placement section 42, 46 on which adhesive is disposed and an adhesive non-disposition section 43, 47 on which no adhesive is disposed [see reference]. Figure 3 (a) and (b)]. Hereinafter, the adhesive placement section 42 in the first bonding region 41 will be referred to as "first adhesive placement section 42", and the adhesive non-placement section 43 in the first bonding region 41 will be referred to as "first adhesive non-placement section 43". In addition, the adhesive placement section 46 in the second bonding region 45 will be referred to as "second adhesive placement section 46", and the adhesive non-placement section 47 in the second bonding region 45 will be referred to as "second adhesive non-placement section 47".

[0046] In the first bonding region 41, the first adhesive placement portion 42 and the first adhesive non-placement portion 43 are alternately arranged in the longitudinal direction X and extend along the transverse direction Y, respectively. Furthermore, in the second bonding region 45, the second adhesive placement portion 46 and the second adhesive non-placement portion 47 are alternately arranged in the longitudinal direction X and extend along the transverse direction Y, respectively. That is, in each of the first bonding region 41 and the second bonding region 45, the adhesive is applied intermittently in stripes extending in the transverse direction Y.

[0047] The first bonding region 41 is located in the area overlapping with the absorber 22, and like the absorber 22, it has a rectangular shape when viewed from above [see reference]. Figure 3 (a) The positions of the two ends of the first bonding region 41 in the transverse Y direction are approximately the same as the positions of the two ends of the absorbent body 2 in the transverse Y direction. The positions of the two ends of the first bonding region 41 in the longitudinal X direction are approximately the same as the positions of the two ends of the absorbent body 22 in the longitudinal X direction.

[0048] The second joining region 45 is disposed in the outer body 3 (third piece 13) in the region formed by the portion that narrows inward from the central region in the longitudinal direction X toward the transverse direction Y, and the portion located inside the longitudinal direction X of the ventral side A and the dorsal side B and adjacent to the narrowed portion in the longitudinal direction X [see reference]. Figure 3 (b)]. In the second bonding region 45, the second adhesive placement portion 46 is continuously disposed along the entire length of the transverse Y of the region. The two ends of the longitudinal X of the second bonding region 45 are located on the inner side of the longitudinal X compared to the two ends of the longitudinal X of the absorber 22.

[0049] When viewed from above, the first joining region 41 and the second joining region 45 at least partially overlap. In this embodiment, the first joining region 41 overlaps with the second joining region 45 on its longitudinal X-shaped inner side. Hereinafter, the area where the first joining region 41 and the second joining region 45 overlap will also be referred to as the "overlapping region 48" (see reference). Figure 3 (b)). In this embodiment, the overlapping region 48 extends in the longitudinal direction X when viewed from above, and is arranged to partially overlap with the absorber 22 [see reference]. Figure 3 [of (a) and (b)].

[0050] Figure 4 This is a cross-sectional view along the longitudinal direction X of the back sheet 10 in the overlapping region 48. Figure 4 The diagram shows the back sheet 10 elongated in the longitudinal direction (X). The area ratio of the adhesive placement portion in the first bonding region 41 is lower than that in the second bonding region 45. In other words, the area ratio of the non-adhesive placement portion in the first bonding region 41 is higher than that in the second bonding region 45. The advantages of having different area ratios of the adhesive placement portions in the first bonding region 41 and the second bonding region 45 are described below.

[0051] Figure 5 (a) and (b) show cross-sectional views of the back sheet 10 in its non-elongated state along the longitudinal direction X. Figure 5 In (a) and (b), reference numeral 20 indicates a component of the diaper 1 located on the skin-facing side of the back panel 10.

[0052] like Figure 5 As shown in (a), in the back panel 10 of the diaper 1, the first panel 11 and the second panel 12 are in a non-attached state at the first adhesive non-positioning portion 43, and the second panel 12 and the third panel 13 are in a non-attached state at the second adhesive non-positioning portion 47. Consequently, folds bulging towards the non-skin-facing side are formed at the first adhesive non-positioning portion 43 and the second adhesive non-positioning portion 47, respectively. In this case, because the area ratio of the adhesive placement portion in the first engagement region 41 is lower than that in the second engagement region 45, smaller folds are formed at the second adhesive non-positioning portion 47 than those at the first adhesive non-positioning portion 43. Furthermore, as... Figure 5 As shown in (a), a pleated structure is formed in the overlapping region 48, where the pleats of the first adhesive non-placement portion 43 and the pleats of the second adhesive non-placement portion 47 overlap in the thickness direction Z. Therefore, when the back sheet 10 is touched with a finger, a tactile sensation is produced, as if the back sheet 10 is gradually flattened, providing a good cushioning feel. In the direction orthogonal to the extending direction of the adhesive placement portions 42 and 46 ( Figure 5When the non-skin-facing side of the overlapping area 48 is touched in the direction indicated by the arrow in (b), the fine folds of the second adhesive non-positioning portion 47 follow the larger folds of the first adhesive non-positioning portion 43, thus the back sheet 10 exhibits a smooth touch and excellent feel [see reference]. Figure 5 (b) Furthermore, when the fine folds are formed in the second adhesive non-positioning portion 47, the wrinkles caused by the joining of the second piece 12 and the third piece 13 are inconspicuous, and the appearance of the non-skin-facing side of the overlapping area 48 becomes good. Therefore, in the diaper 1, both the good appearance and the good skin feel can be taken into account. Furthermore, the interior of the folds in the first adhesive non-positioning portion 43 and the interior of the folds in the second adhesive non-positioning portion 47 function as air channels, thus maintaining the breathability of the back cover sheet 10 well.

[0053] The first bonding region 41 is the region described below: a region surrounded by a virtual line connecting the end edges of the first adhesive placement portions 42 that are adjacent to each other in the longitudinal X or transverse Y direction, separated by the first adhesive non-placement portions 43, and the outermost end edges of the first adhesive placement portions 42 located in the orthogonal direction on both sides of the direction orthogonal to the extension direction of the first adhesive placement portions 42.

[0054] The second bonding region 45 is the region described below: a region surrounded by a virtual line connecting the end edges of the second adhesive placement portions 46 adjacent to each other in the longitudinal X or transverse Y direction, separated by the second adhesive non-placement portion 47, and the outermost end edges of the second adhesive placement portions 46 located in the orthogonal direction on both sides of the direction orthogonal to the extension direction of the second adhesive placement portion 46.

[0055] From the viewpoint of further improving the above-mentioned effect, the area ratio of the first adhesive placement portion 42 in the first bonding region 41 relative to the area ratio of the second adhesive placement portion 46 in the second bonding region 45 (area ratio of the first adhesive placement portion 42 / area ratio of the second adhesive placement portion 46) is preferably 0.2 or more, more preferably 0.3 or more, and preferably 0.9 or less, more preferably 0.7 or less. Furthermore, it is preferably 0.2 or more and 0.9 or less, and more preferably 0.3 or more and 0.7 or less.

[0056] The area ratio of the first adhesive placement portion 42 in the first bonding region 41 is preferably 10% or more, more preferably 12% or more, and preferably 50% or less, more preferably 25% or less.

[0057] The area ratio of the second adhesive placement portion 46 in the second bonding region 45 is preferably 12% or more, more preferably 15% or more, and preferably 50% or less, more preferably 35% or less.

[0058] The area ratio of the first adhesive placement section 42 can be obtained by dividing the total area of ​​the first adhesive placement section 42 in the first bonding region 41 by the area of ​​the first bonding region 41 (total area of ​​the first adhesive placement section 42 / area of ​​the first bonding region 41).

[0059] The area ratio of the second adhesive placement section 46 can be obtained by dividing the total area of ​​the second adhesive placement section 46 in the second bonding region 45 by the area of ​​the second bonding region 45 (total area of ​​the second adhesive placement section 46 / area of ​​the second bonding region 45).

[0060] The area ratio of the first adhesive preparation section 42 and the area ratio of the second adhesive preparation section 46 can be measured, for example, by the following methods.

[0061] First, a sample sheet is cut from the overlapping region 48, showing the portion joined in the first joining region 41 or the second joining region 45. Specifically, a sample sheet is cut from the first piece 11 and the second piece 12 joined together in the first joining region 41, or a sample sheet is cut from the second piece 12 and the third piece 13 joined together in the second joining region 45. Components unrelated to the bonding of the adhesive preparation section being measured are removed from the sample sheet. For example, when measuring the area ratio of the first adhesive preparation section 42, the third piece 13 is peeled off from the sample sheet using a cold spray gun or the like. At this time, other components are peeled off from the sample sheet in a manner that does not affect the bonding state of the adhesive preparation section being measured. The sample sheet size is set to 50mm × 50mm.

[0062] Next, the sample sheets are peeled apart using a cold spray gun or similar method, exposing the surface with the adhesive coating. Printing toner is then evenly distributed onto the adhesive-coated surface. After the printing toner is absorbed by the adhesive, any printing toner not absorbed is removed. The removal of the printing toner is performed by blowing air or suction.

[0063] Next, an image of the surface with the printing toner adsorbed was obtained using a scanner (Seiko Epson ES-10000G). This image was binarized to black and white, allowing for the differentiation between the areas with and without the adsorbed printing toner.

[0064] Next, the area ratio of the portion of the image in which the printing toner was adsorbed was measured using image analysis software (e.g., Image-Pro Plus, manufactured by ROPER Co., Ltd., Japan). Based on a pre-measured reference value, this area ratio measurement was converted into the area ratio of the adhesive application portion in the sample sheet. The reference value was obtained by measuring the area ratio of the adhesive application portion of the reference sample sheet using the same method as described above. The reference sample sheet (50mm × 50mm) was obtained by applying adhesive to a nonwoven fabric in a striped pattern so that the area ratio of the adhesive application portion was 50%. More specifically, in the reference sample sheet, the coated portion with adhesive and the uncoated portion without adhesive each extended in one direction, and these coated and uncoated portions were alternately arranged in a direction orthogonal to that direction. The width of each coated and uncoated portion in the reference sample sheet was 1mm, and the amount of adhesive applied in the coated portion was 3g / m². 2 .

[0065] Unless otherwise specified, with the back sheet 10 extended in a direction orthogonal to the extending direction of the adhesive placement portions 42 and 46 (longitudinal X in this embodiment), the areas of the first bonding region 41 and the second bonding region 45, and the widths of the adhesive placement portions 42 and 46 and the adhesive non-placement portions 43 and 47, etc., are measured (see reference). Figure 3 That is, the measurement is taken when the folds of the first adhesive non-configuration section 43 and the second adhesive non-configuration section 47 have disappeared.

[0066] From the viewpoint of further improving the above-mentioned effect, the areas of the first joint region 41 and the second joint region 45 are preferably within the following ranges.

[0067] The ratio of the area of ​​the overlapping region 48 to the area of ​​the first joining region 41 is preferably 30% or more, more preferably 40% or more, and preferably 90% or less, more preferably 80% or less.

[0068] The ratio of the area of ​​the overlapping region 48 to the area of ​​the second joining region 45 is preferably 20% or more, more preferably 30% or more, and preferably 80% or less, more preferably 70% or less.

[0069] From the viewpoint of making it easier to form the pleated structure and further improving the feel of the back sheet 10, it is preferable that the width of the adhesive non-positioned portion of the first bonding region 41 is wider than the width of the adhesive non-positioned portion of the second bonding region 45. That is, it is preferable that the width of the first adhesive non-positioned portion 43 is wider than the width of the second adhesive non-positioned portion 47.

[0070] Regarding the same viewpoint as above, the width W3 of the first adhesive non-configuration portion 43 (refer to...) Figure 4 The width W7 relative to the non-configuration portion 47 of the second adhesive (see reference) Figure 4 The content is preferably 120% or more, more preferably 150% or more, and preferably 1000% or less, more preferably 500% or less.

[0071] In this specification, the width of the adhesive placement portions 42, 46 or the adhesive non-placement portions 43, 47 is the length of the adhesive placement portions 42, 46 or the adhesive non-placement portions 43, 47 in a direction orthogonal to the extending direction of the adhesive placement portions 42, 46 and the adhesive non-placement portions 43, 47. In this embodiment, the orthogonal direction is consistent with the longitudinal direction X.

[0072] From the viewpoint of making the pleated structure easier to move and further improving the skin feel of the back panel 10, the width W6 of the second adhesive placement portion 46 in the second bonding region 45 is preferably (refer to...). Figure 4 The width W2 of the first adhesive placement portion 42 in the first bonding region 41 is less than or equal to the width W2.

[0073] Regarding the same point of view as above, the width W6 of the second adhesive placement section 46 (refer to...) Figure 4 The width W2 relative to the first adhesive placement section 42 (refer to) Figure 4 The content is preferably 20% or more, more preferably 30% or more, and preferably 100% or less, more preferably 90% or less.

[0074] From the viewpoint of further improving the appearance of the outer surface of the diaper 1, it is preferable that the width of the second adhesive placement portion 46 in the second joining area 45 is narrower than the width of the second adhesive non-placement portion 47. By adopting this structure, the wrinkles caused by the joining of the second piece 12 and the third piece 13 become less visible.

[0075] Regarding the same point of view as above, the width W6 of the second adhesive placement section 46 (refer to...) Figure 4 The width W7 relative to the non-configuration portion 47 of the second adhesive (see reference) Figure 4The content is preferably 10% or more, more preferably 20% or more, and preferably 90% or less, more preferably 70% or less.

[0076] From the viewpoint of more reliably achieving one or more of the above-mentioned effects, it is preferable that the widths of the adhesive placement portions 42, 46 and the adhesive non-placement portions 43, 47 of the first bonding region 41 and the second bonding region 45 are within the following ranges.

[0077] The width W2 of the first adhesive preparation section 42 (refer to) Figure 4 The thickness is preferably 0.5 mm or more, more preferably 0.8 mm or more, and preferably 5.0 mm or less, more preferably 3.0 mm or less. It is also preferred that the thickness is 0.5 mm or more and 5.0 mm or less, and more preferably 0.8 mm or more and 3.0 mm or less.

[0078] The width W3 of the non-dispensing portion 43 of the first adhesive (refer to) Figure 4 The thickness is preferably 1.0 mm or more, more preferably 1.5 mm or more, and preferably 10.0 mm or less, more preferably 7.0 mm or less. It is also preferably 1.0 mm or more and 10.0 mm or less, and more preferably 1.5 mm or more and 7.0 mm or less.

[0079] The width W6 of the second adhesive preparation section 46 (refer to) Figure 4 The thickness is preferably 0.5 mm or more, more preferably 0.8 mm or more, and preferably 4.0 mm or less, more preferably 2.5 mm or less. It is also preferred that the thickness is 0.5 mm or more and 4.0 mm or less, and more preferably 0.8 mm or more and 2.5 mm or less.

[0080] The width W7 of the non-dispensing portion 47 of the second adhesive (refer to) Figure 4 The thickness is preferably 0.3 mm or more, more preferably 0.5 mm or more, and preferably 8.0 mm or less, more preferably 5.0 mm or less. It is also preferred that the thickness is 0.3 mm or more and 8.0 mm or less, and more preferably 0.5 mm or more and 5.0 mm or less.

[0081] In the diaper 1 of this embodiment, the core elastic member 31 of the absorbent body 22, the flange elastic member 35 of the leak-proof flange 26, and the outer flange elastic member 32 are respectively configured to overlap with the overlapping area 48 (not shown) when viewed from above. Furthermore, in the diaper 1, the leg elastic members 37 of the outer body 3 are located on both sides of the transverse Y-axis of the overlapping area 48 (not shown). Thus, in the diaper 1 with adhesive placement portions 42 and 46 extending transversely Y-axis at intervals, it is preferable that elastic members having elasticity in the longitudinal X-axis are configured to overlap with the overlapping area 48 when viewed from above, or to be respectively located on both sides of the transverse Y-axis of the overlapping area 48. When the diaper 1 has such a structure, the pleated structure is more easily formed by the contraction of the elastic members 31, 32, 35, and 37, thereby further improving the cushioning and feel of the backing sheet 10. The diaper 1 having the above structure preferably has any one of elastic members 31, 32, 35 arranged to overlap with the overlapping area 48 when viewed from above, and elastic members 37 respectively arranged on both sides of the transverse Y of the overlapping area 48, and more preferably has both.

[0082] In the top view, when any one or both of the elastic members 31, 32, 35 arranged to overlap with the overlapping region 48 and the elastic members 37 respectively arranged on both sides of the transverse Y of the overlapping region 48 extend, the folds in the first adhesive non-distribution portion 43 and the second adhesive non-distribution portion 47 disappear (see reference). Figure 4 Alternatively, the height of each pleat may decrease. On the other hand, when one or both of the elastic members 31, 32, 35 arranged to overlap with the overlapping region 48 and the elastic members 37 respectively arranged on both sides of the transverse Y of the overlapping region 48 are contracted, the height of each pleat in the first adhesive non-distribution portion 43 and the second adhesive non-distribution portion 47 increases (see reference). Figure 5 [a] From the viewpoint that it is easier to form the pleated structure formed by the contraction of the elastic member, it is preferable that at least one of the first engagement region 41 and the second engagement region 45 contains the same structure as when the elastic member contracts [refer to] Figure 5 Compared to (a), when the elastic member is stretched (refer to) Figure 4 The adhesive non-configuration parts 43 and 47 are wider. In this case, the natural state (the state without external force applied) of the longitudinally stretching elastic members 31, 32, 35, and 37 is taken as "when the elastic members are contracted", and the maximum elongation of the diaper 1 in the longitudinal X direction is taken as "when the elastic members are stretched".

[0083] Regarding the same viewpoint as above, the width of the adhesive non-configuration portions 43, 47 when the elastic member is stretched or contracted is preferably within the following range.

[0084] When the width of the adhesive non-positioned portions 43 and 47 when the elastic member is extended is W, and the width of the adhesive non-positioned portions 43 and 47 when the elastic member is contracted is W′, the ratio of W′ to W (W′ / W) is preferably 20% or more, more preferably 30% or more, and preferably 90% or less, more preferably 80% or less. Specifically, this ratio is the ratio of the width W3′ of the first adhesive non-positioned portion 43 when the elastic member is contracted to the width W3 of the first adhesive non-positioned portion 43 when the elastic member is extended (W3′ / W3), or the ratio of the width W7′ of the second adhesive non-positioned portion 47 when the elastic member is contracted to the width W7 of the second adhesive non-positioned portion 47 when the elastic member is extended (W7′ / W7).

[0085] The width W3′ of the first adhesive non-distribution portion 43 when the elastic component contracts [refer to] Figure 5 (a) is preferably 0.5 mm or more, more preferably 1.0 mm or more, and preferably 8.0 mm or less, more preferably 6.0 mm or less. It is also preferably 0.5 mm or more and 8.0 mm or less, and more preferably 1.0 mm or more and 5.0 mm or less.

[0086] The width W7′ of the second adhesive non-distribution portion 47 when the elastic component contracts [refer to] Figure 5 (a) is preferably 0.2 mm or more, more preferably 0.4 mm or more, and preferably 7.0 mm or less, more preferably 5.0 mm or less.

[0087] As described above, the first sheet 11 is a breathable membrane, and the second sheet 12 and the third sheet 13 are fiber sheets formed of fibrous material. From the viewpoint of more easily forming the pleated structure, in the diaper 1 of this embodiment, it is preferable that the constituent fibers of at least one of the second sheet 12 and the third sheet 13 are oriented in the transverse Y direction. That is, it is preferable that the constituent fibers of at least one of the second sheet 12 and the third sheet 13 are oriented in the extending direction of the adhesive placement portions 42, 46.

[0088] The orientation of the fibers in the sheet can be confirmed by the following method. First, the sheet to be measured is removed from the absorbent material by peeling or similar means using a cold spray machine. The removed sheet is cut into a top-view quadrilateral shape with a length of 2 cm in the longitudinal direction (X) and a length of 2 cm in the transverse direction (Y) using a knife or similar means, and this is used as the measurement sheet. The measurement sheet is cut from the overlapping area 48 of the second sheet 12 or the third sheet 13. Next, the measurement sheet is observed at a magnification of 60 to 200 times using a microscope (e.g., KEYENCE VHX-1000 digital microscope). For any fiber observed within a certain observation area (e.g., 1 mm square), two points are defined such that the fiber length in that area is the maximum. Then, the angle formed by the straight line connecting the two ends and the transverse direction (Y) is measured. This measurement is performed in at least 3 observation areas, and the arithmetic mean (average angle) of the angles measured for a total of 30 or more fibers is calculated. When the average angle is within 45 degrees, it is determined that the constituent fibers are oriented in the transverse direction (Y); when the average angle exceeds 45 degrees, it is determined that the constituent fibers are oriented in the longitudinal direction (X). In the above measurements, it is preferable to observe at a magnification that allows more than 10 fibers to be identified within the observation area.

[0089] From the viewpoint of making the pleats in the back sheet 10 easier to move, further improving the softness of the back sheet 10, and further improving the formability of the pleats, the ring crush strength (hereinafter also referred to as "ring crush strength") of at least one of the second sheet 12 and the third sheet 13 when compressed in a direction orthogonal to the orientation direction of the constituent fibers is preferably 1.0 cN or more, more preferably 1.5 cN or more, and preferably 7.0 cN or less, more preferably 5.0 cN or less.

[0090] Ring crush strength can be measured as follows. First, a sheet of the object to be measured is removed from the absorbent material using a cold spraying machine or similar method by peeling. Five rectangular pieces are cut from the removed sheet, each 80 mm long along the orientation direction of the constituent fibers and 30 mm long along a direction orthogonal to the orientation direction. These are used as test pieces. Each test piece is rolled into a cylinder along its length, with one end overlapping the other by 10 mm to form a cylinder with an outer circumference of 70 mm. The overlapping portions are then secured at the top (upper end of the cylinder's axial direction) and bottom ends using staples (e.g., MAX No. 10-1M staples), resulting in five cylindrical measurement samples. The staples are aligned parallel to the circumference of the measurement sample. Each measured sample (initial sample width: 30 mm) was placed on a TENSILON compression testing machine (ORIENTEC Co., Ltd. "RTA-100"), and the maximum load (cN) displayed when compressed axially (in the width direction of the test piece) with a circular compression plate of 70 mm or more in diameter at a compression rate of 10 mm / min was measured. The same measurement was performed on five samples, and their arithmetic mean was taken as the ring crush strength of the piece. The measurement environment was room temperature 23 ± 2 °C and relative humidity 50% RH ± 5%.

[0091] From the viewpoint of making the pleats of the back panel 10 more movable and further improving the feel against the skin, it is preferable that the ring compression strength of the third panel 13 is smaller when compressed in a direction orthogonal to the orientation direction of the constituent fibers compared to the second panel 12.

[0092] With regard to the same point above, it is preferable that the ring compression strength of each of the first piece 11, the second piece 12, and the third piece 13 is within the following range.

[0093] The ring compression strength of the first piece 11 is preferably 1.0 cN or more, more preferably 1.5 cN or more, and preferably 7.0 cN or less, more preferably 5.0 cN or less. Furthermore, it is preferably 1.0 cN or more and 7.0 cN or less, and more preferably 1.5 cN or more and 5.0 cN or less.

[0094] The ring compression strength of the second piece 12 is preferably 1.0 cN or more, more preferably 1.5 cN or more, and preferably 7.0 cN or less, more preferably 5.0 cN or less. Furthermore, it is preferably 1.0 cN or more and 7.0 cN or less, and more preferably 1.5 cN or more and 5.0 cN or less.

[0095] The ring compression strength of the third piece 13 is preferably 0.5 cN or more, more preferably 1.0 cN or more, and preferably 6.0 cN or less, more preferably 4.0 cN or less.

[0096] From the viewpoint of making the pleats of the back panel 10 more movable and further improving the feel against the skin, it is preferable that the weight of the third panel 13 is lower than that of the second panel 12.

[0097] Regarding the same viewpoint as above, it is preferable that the weights of the first piece 11, the second piece 12, and the third piece 13 are each within the following range.

[0098] The preferred weight of the first piece (11) is 5g / m³. 2 The above, preferably 8g / m 2 In addition, the preferred value is 40g / m³. 2 The following is more preferably 30g / m 2 Furthermore, 5g / m² is preferred. 2 Above and 40g / m 2 The preferred value is 8g / m 2 Above and 30g / m 2 the following.

[0099] The preferred weight of the second piece (12) is 5g / m³. 2 The above, preferably 8g / m 2 In addition, the preferred value is 30g / m³. 2 The following is more preferably 20g / m 2 Furthermore, 5g / m² is preferred. 2 Above and 30g / m 2 The preferred value is 8g / m 2 Above and 20g / m 2 the following.

[0100] The preferred weight of the third piece (13) is 5g / m³. 2 The above, preferably 8g / m 2 In addition to the above, the preferred value is 25g / m³. 2 The following is more preferably 20g / m 2 Furthermore, 5g / m² is preferred. 2 Above and 25g / m 2 The preferred value is 8g / m 2 Above and 20g / m 2 the following.

[0101] From the viewpoint of facilitating the movement of the folds in the back panel 10 and further improving the skin feel, it is preferable that the density of the third panel 13 is lower than that of the second panel 12. The density of each panel can be calculated by dividing its weight by its thickness. The thickness of the panel is the thickness of the panel under a load of 0.05 kPa. The thickness can be measured using, for example, a non-contact laser displacement meter.

[0102] Regarding the same viewpoint as above, it is preferable that the weights of the first piece 11, the second piece 12, and the third piece 13 are each within the following range.

[0103] The preferred density of the first piece (11) is 30 × 10⁻⁶. -6 g / mm 3 The above, more preferably 50×10 -6 g / mm 3 In addition, 300×10 is preferred. -6 g / mm 3 The following is more preferably 200×10 -6 g / mm 3 Furthermore, 30×10 is preferred. -6 g / mm 3 Above and 300×10 -6 g / mm 3 The following is more preferably 50×10 -6 g / mm 3 Above and 200×10 -6 g / mm 3 the following.

[0104] The preferred density of the second piece of 12 is 30×10. -6 g / mm 3 The above is preferred, with 50×10 being more ideal. -6 g / mm 3 In addition, 200×10 is preferred. -6 g / mm 3 Hereinafter, 150×10 is preferred. -6 g / mm 3 Furthermore, 30×10 is preferred. -6 g / mm 3 Above and 200×10 -6 g / mm 3 The following is more preferably 50×10 -6 g / mm 3 Above and 150×10 -6 g / mm 3 the following.

[0105] The preferred density of the third piece (13) is 30 × 10⁻⁶. -6 g / mm 3The above is preferred, with 50×10 being more ideal. -6 g / mm 3 In addition, the preferred size is 180×10. -6 g / mm 3 Hereinafter, 150×10 is preferred. -6 g / mm 3 Furthermore, 30×10 is preferred. -6 g / mm 3 Above and 180×10 -6 g / mm 3 The following is more preferably 50×10 -6 g / mm 3 Above and 150×10 -6 g / mm 3 the following.

[0106] When forming the first bonding region 41, the adhesive is applied to the non-skin-facing side of the first piece 11 or the skin-facing side of the second piece 12. When forming the second bonding region 45, the adhesive is applied to the non-skin-facing side of the second piece 12 or the skin-facing side of the third piece 13. The adhesive can be a non-water-soluble adhesive. Examples of non-water-soluble adhesives include adhesives formed from hydrophobic thermoplastic resins, such as styrene-ethylene-butene-styrene (SEBS), styrene-isoprene-styrene (SIS), styrene-butene-styrene (SBS), styrene-ethylene-propylene-styrene (SEPS), ethylene-vinyl acetate (EVA), polyvinyl alcohol (PVA), and other hot-melt adhesives. The adhesive can be used alone or in combination of two or more of the above-mentioned components.

[0107] The adhesive coating pattern can be any pattern without particular limitation, such as the spaced-out areas that form the adhesive. For example, the adhesive coating pattern can be stripes extending in one direction (see reference). Figure 6 (a) can also be spiral-shaped (see reference). Figure 6 (b)]. Furthermore, the adhesive preparation sections 42 and 46 can be wavy (see [reference]). Figure 6 (c) can also be a pattern (not shown) that extends in one direction from a collection of multiple points.

[0108] From the viewpoint that it is easier to satisfy the area ratio relationship between the first bonding region 41 and the second bonding region 45 (first bonding region 41 < second bonding region 45), it is preferable that the adhesive application width of the adhesive forming the first adhesive placement portion 42 and the second adhesive placement portion 46 is the same [ref]. Figure 6(a) to (c)]. In this manner, the arrangement pitch of the adhesive placement portion in the first bonding region 41 and the second bonding region 45 in a direction orthogonal to the extending direction of the adhesive placement portion is different.

[0109] The weight (amount applied per unit area) of the adhesive in the first adhesive preparation section 42 and the second adhesive preparation section 46 may be the same or different.

[0110] From the viewpoint of more reliably ensuring the bonding strength between the absorbent body 2 and the outer casing 3, the basis weight of the adhesive in the first adhesive preparation section 42 is preferably 1.0 g / m³. 2 The above, more preferably 2.0 g / m 2 In addition, the preferred value is 15.0 g / m³. 2 The following is more preferably 10.0 g / m 2 Below, and furthermore, 1.0 g / m is preferred. 2 Above and 15.0g / m 2 The following is more preferably 2.0 g / m 2 Above and 10.0g / m 2 the following.

[0111] From the viewpoint of more reliably ensuring the bonding strength between the second piece 12 and the third piece 13, and between these two pieces and the leg elastic member 37, the basis weight of the adhesive in the second adhesive application section 46 is preferably 1.0 g / m². 2 The above, more preferably 2.0 g / m 2 In addition, the preferred value is 15.0 g / m³. 2 The following is more preferably 10.0 g / m 2 Below, and furthermore, 1.0 g / m is preferred. 2 Above and 15.0g / m 2 The following is more preferably 2.0 g / m 2 Above and 10.0g / m 2 the following.

[0112] Furthermore, the basis weight of the adhesives forming the respective adhesive preparation portions 42, 46 in the first bonding region 41 or the second bonding region 45 can be the same or different.

[0113] The forming materials of each part of the diaper 1 in the above embodiment will be described in detail. As the front sheet 21 and the absorbent body 22, the materials that have been used in absorbent articles can be used without particular limitation.

[0114] For example, liquid-permeable nonwoven fabrics and perforated membranes can be used as the front sheet 21.

[0115] In the absorbent body 22, the absorbent core 24 can be an aggregate of hydrophilic fibers such as wood pulp or synthetic fibers that have undergone hydrophilic treatment, and this aggregate can maintain the structure of a water-absorbing polymer. Furthermore, the cover chip 25 can be made of the same material as the front sheet 21.

[0116] When the first sheet 11 of the back sheet 10 is a leak-proof sheet 28, the first sheet 11 can be a sheet that is impermeable to liquids or water-repellent. This sheet can be a resin film, a laminate of a resin film and non-woven fabric, etc. Examples of resin films include films formed from polymer materials such as polyethylene terephthalate, polyester, polyethylene, polypropylene, cellophane, nylon, polyvinyl alcohol, polyvinyl chloride, and polycarbonate, as well as moisture-permeable films.

[0117] When the second piece 12 and the third piece 13 of the back sheet 10 are outer bodies 3, the second piece 12 and the third piece 13 can be made of nonwoven fabrics made by various manufacturing methods, such as spunbond nonwoven fabric, hot air nonwoven fabric, spunlace nonwoven fabric, hot roller nonwoven fabric, meltblown nonwoven fabric or their laminated nonwoven fabrics.

[0118] From the viewpoint of further improving the cushioning and softness of the back sheet 10, it is preferable that at least one of the second sheet 12 and the third sheet 13 has a fiber layer containing crimped fibers. For example, it is possible to exemplify that at least one of the second sheet 12 and the third sheet 13 is a laminated nonwoven fabric having a fiber layer containing crimped fibers. Similarly, from the same viewpoint, it is preferable that the non-skin-facing side of the third sheet 13 is formed of a fiber layer containing crimped fibers.

[0119] As shrinkable fibers, mechanically shrinkable fibers that are two-dimensionally shrinkable into a serrated shape through mechanical shrinkage, three-dimensionally shrinkable fibers that are three-dimensionally shrinkable into a spiral shape through mechanical shrinkage, and potentially shrinkable fibers that are three-dimensionally shrinkable into a coil shape through heat application can be used. Examples of shrinkable fibers include fibers formed from eccentric core-sheath type or side-by-side type composite fibers composed of two thermoplastic polymer materials with different shrinkage rates. More specifically, fibers described in Japanese Patent Application Publication No. 9-296325, Japanese Patent Publication No. 2759331, and Japanese Patent Publication No. 5404967 can be cited.

[0120] From the viewpoint of making the fibers move more easily when in contact with fingers, further improving smoothness and cushioning, and more reliably ensuring the bonding strength at the second bonding area 45, it is preferable that the fiber layer forming the non-skin-facing side of the third sheet 13 contains curled fibers, while the fiber layer forming the skin-facing side does not contain the curled fibers. As such, a structure of a laminated nonwoven fabric formed by stacking fiber layers containing curled fibers and fiber layers without curled fibers on the third sheet 13 can be cited.

[0121] When at least one of the second sheet 12 and the third sheet 13 has a fiber layer containing curled fibers, for the same reason as described above, the proportion of curled fibers in the fiber layer containing curled fibers relative to the total mass of the fibers in the fiber layer is preferably 10% by mass or more, more preferably 20% by mass or more, and preferably 100% by mass or less, more preferably 80% by mass or less. Furthermore, it is preferably 10% by mass or more and 100% by mass or less, more preferably 20% by mass or more and 80% by mass or less.

[0122] The core elastic component 31 of the absorbent body 22, the flange elastic component 35 and the outer flange elastic component 32 of the leak-proof flange 26, and the leg elastic component 37, etc., can use various known elastic materials commonly used in such absorbent articles without particular limitations. Examples of elastic materials include synthetic rubbers such as styrene-butadiene, butadiene, isoprene, and chloroprene rubber, natural rubber, EVA, stretchable polyolefins, and polyurethane. As for the shape of the elastic component, linear (rubber thread, etc.) or strip (rubber strip, etc.) elastic components with cross-sections of rectangles, squares, circles, polygons, etc., are preferred, as are multifilament linear elastic components.

[0123] The present invention has been described above based on preferred embodiments, but the present invention is not limited to the above embodiments.

[0124] For example, the absorbent material mentioned above is a shorts-type disposable diaper, but it can also be an unfolded disposable diaper. It can be an absorbent material for infants or young children, or an absorbent material for adults.

[0125] In the above embodiment, the extending direction of the first adhesive placement section 42 and the second adhesive placement section 46 is consistent with the transverse direction Y, but the extending direction may also be consistent with the longitudinal direction X.

[0126] In the above embodiments, the absorbent core 24 has bending guide portions 23C and 23S, but it may also lack bending guide portions 23C and 23S. Furthermore, the absorbent core 24 may have a double-layer structure or a single-layer structure. Additionally, the absorbent core 24 may also lack the core elastic member 31.

[0127] In the above embodiment, the leak-proof flange 26 has an outer flange elastic member 32, but it may also not have the outer flange elastic member 32.

[0128] In addition, for example Figure 1The outer garment 3 shown is continuously provided from the abdominal side A through the crotch C to the back side B. However, instead of this structure, the outer garment 3 can also be a split outer garment that is divided into a back panel component disposed on the back side of the wearer and an abdominal panel component disposed on the abdomen side. The back panel component and the abdominal panel component are joined together by a pair of side seals to form a tubular shape, and the absorbent body is mounted and fixed between the back panel component and the abdominal panel component.

[0129] Furthermore, in the above embodiment, the outer casing 3 has a double-layer structure of the second piece 12 and the third piece 13, but the outer casing 3 may also have a single-layer structure. In this case, the piece constituting the outer casing 3 is the third piece 13, and the two pieces located between the third piece 13 and the absorbent core 24 in the thickness direction of the diaper 1 are the first piece 11 and the second piece 12. As an example, the following configuration can be provided: the absorbent body 22 has an absorbent core 24, a skin-side packing chip covering the skin-facing side of the absorbent core 24, and a non-skin-facing packing chip covering the non-skin-facing side of the absorbent core 24, wherein on the non-skin-facing side of the absorbent core 24, there are, in sequence, a non-skin-facing packing chip, a moisture-permeable membrane, and a nonwoven fabric. In this case, the non-skin-facing packing chip becomes the first piece 11, the moisture-permeable membrane becomes the second piece 12, and the nonwoven fabric becomes the third piece 13.

[0130] Regarding the embodiments of the present invention described above, the following absorbent articles are further disclosed.

[0131] <1>

[0132] An absorbent article having a front sheet, a back sheet, and an absorbent core disposed between the front sheet and the back sheet, and having a longitudinal direction corresponding to the wearer's front-back direction and a transverse direction orthogonal to the longitudinal direction, characterized in that:

[0133] The back panel has a first panel, a second panel, and a third panel sequentially arranged from the skin-facing side to the non-skin-facing side.

[0134] The third piece forms the non-skin-facing side of the absorbent article.

[0135] The device has a first bonding region where the first piece and the second piece are joined by an adhesive, and a second bonding region where the second piece and the third piece are joined by an adhesive, wherein the first bonding region and the second bonding region at least partially overlap when viewed from above.

[0136] The first bonding region and the second bonding region each have an adhesive placement section with the adhesive disposed thereon and an adhesive non-placement section without the adhesive disposed thereon.

[0137] The area ratio of the adhesive configuration portion in the first bonding region is lower than that in the second bonding region.

[0138] <2>

[0139] As mentioned above <1> The absorbent article, wherein,

[0140] The ratio of the area ratio of the adhesive placement portion in the first bonding region to the area ratio of the adhesive placement portion in the second bonding region is 0.2 or more and 0.9 or less, preferably 0.3 or more and 0.7 or less.

[0141] <3>

[0142] As mentioned above <2> The absorbent article, wherein,

[0143] The area ratio of the adhesive placement portion in the first bonding region is 10% or more and 50% or less, more preferably 12% or more and 25% or less.

[0144] <4>

[0145] As mentioned above <2> or <3> The absorbent article, wherein,

[0146] The area ratio of the adhesive placement portion in the second bonding region is 12% or more and 50% or less, more preferably 15% or more and 35% or less.

[0147] <5>

[0148] As mentioned above <1> ~ <4> The absorbent article described in any one of the following statements, wherein,

[0149] In the first and second bonding regions, the adhesive-placed portions and the adhesive-free portions are alternately arranged in the longitudinal direction and extend in the transverse direction, respectively.

[0150] The width of the adhesive non-configured portion in the first bonding region is wider than the width of the adhesive non-configured portion in the second bonding region.

[0151] <6>

[0152] As mentioned above <5> The absorbent article, wherein,

[0153] The ratio of the width of the adhesive non-configured portion in the first bonding region to the width of the adhesive non-configured portion in the second bonding region is 120% or more and 1000% or less, preferably 150% or more and 500% or less.

[0154] <7>

[0155] As mentioned above <6> The absorbent article, wherein,

[0156] In the second bonding region, the width of the adhesive placement portion is smaller than the width of the adhesive non-placement portion.

[0157] <8>

[0158] As mentioned above <7> The absorbent article, wherein,

[0159] In the second bonding region, the ratio of the width of the adhesive placement portion to the width of the adhesive non-placement portion is 10% or more and 90% or less, preferably 20% or more and 70% or less.

[0160] <9>

[0161] As mentioned above <5> ~ <8> The absorbent article described in any one of the following statements, wherein,

[0162] The width of the adhesive placement portion in the second bonding region is less than or equal to the width of the adhesive placement portion in the first bonding region.

[0163] <10>

[0164] As mentioned above <9> The absorbent article, wherein,

[0165] The ratio of the width of the adhesive placement portion in the second bonding region to the width of the adhesive placement portion in the first bonding region is 20% or more and 100% or less, preferably 30% or more and 90% or less.

[0166] <11>

[0167] As mentioned above <1> ~ <10> The absorbent article described in any one of the following statements, wherein,

[0168] When the area where the first joining region and the second joining region overlap in a top view is taken as the overlapping region,

[0169] The ratio of the area of ​​the overlapping region to the area of ​​the first joining region is 30% or more and 90% or less, preferably 40% or more and 80% or less.

[0170] <12>

[0171] As mentioned above <1> ~ <11> The absorbent article described in any one of the following statements, wherein,

[0172] When the area where the first joining region and the second joining region overlap in a top view is taken as the overlapping region,

[0173] The ratio of the area of ​​the overlapping region to the area of ​​the second joining region is 20% or more and 80% or less, preferably 30% or more and 70% or less.

[0174] <13>

[0175] As mentioned above <5> ~ <12> The absorbent article described in any one of the following statements, wherein,

[0176] When the area where the first joining region and the second joining region overlap in a top view is taken as the overlapping region,

[0177] The longitudinally stretchable elastic member is configured to overlap with the overlapping area when viewed from above, or is respectively configured on both sides of the lateral direction of the overlapping area.

[0178] At least one of the first and second bonding regions includes an adhesive non-configuration portion that is wider when the elastic member is stretched than when the elastic member is contracted.

[0179] <14>

[0180] As mentioned above <13> The absorbent article, wherein,

[0181] When the width of the adhesive non-positioned portion when the elastic member is stretched is W, and the width of the adhesive non-positioned portion when the elastic member is contracted is W′, the ratio of W′ to W (W′ / W) is 20% or more and 90% or less, preferably 30% or more and 80% or less.

[0182] <15>

[0183] As mentioned above <1> ~ <14> The absorbent article described in any one of the following statements, wherein,

[0184] In at least one of the second and third pieces, the constituent fibers are oriented in the transverse direction, and the ring compression strength when compressed in a direction orthogonal to the orientation direction is 7.0 cN or less, preferably 1.0 cN or more and 7.0 cN or less, more preferably 1.5 cN or more and 5.0 cN or less.

[0185] <16>

[0186] As mentioned above <15> The absorbent article, wherein,

[0187] The ring compression strength of the third piece is less than that of the second piece.

[0188] <17>

[0189] As mentioned above <15> or <16> The absorbent article, wherein,

[0190] The ring compression strength of the first piece is 1.0 cN or more and 7.0 cN or less, preferably 1.5 cN or more and 5.0 cN or less.

[0191] <18>

[0192] As mentioned above <15> ~ <17> The absorbent article described in any one of the following statements, wherein,

[0193] The ring compression strength of the second piece is 1.0 cN or more and 7.0 cN or less, preferably 1.5 cN or more and 5.0 cN or less.

[0194] <19>

[0195] As mentioned above <15> ~ <18> The absorbent article described in any one of the following statements, wherein,

[0196] The ring compression strength of the third piece is 0.5 cN or more and 6.0 cN or less, preferably 1.0 cN or more and 4.0 cN or less.

[0197] <20>

[0198] As mentioned above <1> ~ <19> The absorbent article described in any one of the following statements, wherein,

[0199] The weight of the third piece is lower than that of the second piece.

[0200] <21>

[0201] As mentioned above <20> The absorbent article, wherein,

[0202] The weight of the first piece is 5g / m³. 2 Above and 40g / m 2 The following is preferred: 8g / m 2 Above and 30g / m 2 the following.

[0203] <22>

[0204] As mentioned above <20> or <21> The absorbent article, wherein,

[0205] The second piece has a weight of 5g / m³. 2 Above and 30g / m 2 The following is preferred: 8g / m 2 Above and 20g / m 2 the following.

[0206] <23>

[0207] As mentioned above <20> ~ <22> The absorbent article described in any one of the following statements, wherein,

[0208] The third piece has a weight of 5g / m³. 2 Above and 25g / m 2 The following is preferred: 8g / m 2 Above and 20g / m 2 the following.

[0209] <24>

[0210] As mentioned above <20> ~ <23> The absorbent article described in any one of the following statements, wherein,

[0211] The density of the third piece is lower than that of the second piece.

[0212] <25>

[0213] As mentioned above <24> The absorbent article, wherein,

[0214] The density of the first piece is 30 × 10⁻⁶. -6 g / mm 3 Above and 300×10 -6 g / mm 3 The following is preferred: 50×10 -6 g / mm 3 Above and 200×10 -6 g / mm 3 the following.

[0215] <26>

[0216] As mentioned above <24> or <25> The absorbent article, wherein,

[0217] The density of the second piece is 30×10. -6 g / mm 3 Above and 200×10 -6 g / mm 3 The following is preferred: 50×10 -6 g / mm 3 Above and 150×10 -6 g / mm 3 the following.

[0218] <27>

[0219] As mentioned above <24> ~ <26> The absorbent article described in any one of the following statements, wherein,

[0220] The density of the third piece is 30 × 10⁻⁶. -6 g / mm 3 Above and 180×10 -6 g / mm 3 The following is preferred: 50×10 -6 g / mm 3Above and 150×10 -6 g / mm 3 the following.

[0221] <28>

[0222] As mentioned above <1> ~ <27> The absorbent article described in any one of the following statements, wherein,

[0223] At least one of the second and third sheets has a fiber layer containing curled fibers.

[0224] <29>

[0225] As mentioned above <28> The absorbent article, wherein,

[0226] The proportion of the curled fibers in the fiber layer containing the curled fibers is 10% by mass or more and 100% by mass or less relative to the total mass of the fibers in the fiber layer, preferably 20% by mass or more and 80% by mass or less.

[0227] <30>

[0228] As mentioned above <28> or <29> The absorbent article, wherein,

[0229] In the third piece, the fiber layer forming the non-skin-facing side contains curled fibers, while the fiber layer forming the skin-facing side does not contain these curled fibers.

[0230] Industrial applications

[0231] The absorbent article according to the present invention can achieve both good appearance and good skin feel.

Claims

1. An absorbent article having a front sheet, a back sheet, and an absorbent core disposed between the front sheet and the back sheet, and having a longitudinal direction corresponding to the wearer's front-back direction and a transverse direction orthogonal to the longitudinal direction, characterized in that: The back panel has a first panel, a second panel, and a third panel sequentially arranged from the skin-facing side to the non-skin-facing side. The third piece forms the non-skin-facing side of the absorbent article. The device has a first bonding region where the first piece and the second piece are joined by an adhesive, and a second bonding region where the second piece and the third piece are joined by an adhesive, wherein the first bonding region and the second bonding region at least partially overlap when viewed from above. The first bonding region and the second bonding region each have an adhesive placement section with the adhesive disposed thereon and an adhesive non-placement section without the adhesive disposed thereon. In the first and second bonding regions, the adhesive-placed portions and the adhesive-free portions are alternately arranged in the longitudinal direction and extend in the transverse direction, respectively. The width of the adhesive non-configured portion in the first bonding region is wider than the width of the adhesive non-configured portion in the second bonding region. The area ratio of the adhesive placement portion in the first bonding region is lower than that in the second bonding region. When the area where the first joining region and the second joining region overlap in a top view is taken as the overlapping region, The longitudinally stretchable elastic member is configured to overlap with the overlapping area when viewed from above, or is respectively configured on both sides of the lateral direction of the overlapping area. By contracting the elastic member, pleats can be formed in the adhesive non-positioned portion of each of the first and second joining regions.

2. The absorbent article as claimed in claim 1, characterized in that: The ratio of the area ratio of the adhesive configuration portion in the first bonding region to the area ratio of the adhesive configuration portion in the second bonding region is 0.2 or more and 0.9 or less.

3. The absorbent article as described in claim 2, characterized in that: The area ratio of the adhesive configuration portion in the first bonding region is 10% or more and 50% or less.

4. The absorbent article as described in claim 2 or 3, characterized in that: The area ratio of the adhesive configuration portion in the second bonding region is 12% or more and 50% or less.

5. The absorbent article according to any one of claims 1 to 3, characterized in that: The ratio of the width of the adhesive non-configured portion in the first bonding region to the width of the adhesive non-configured portion in the second bonding region is more than 120% and less than 1000%.

6. The absorbent article as claimed in claim 5, characterized in that: In the second bonding region, the width of the adhesive placement portion is smaller than the width of the adhesive non-placement portion.

7. The absorbent article as claimed in claim 6, characterized in that: In the second bonding region, the ratio of the width of the adhesive placement portion to the width of the adhesive non-placement portion is more than 10% and less than 90%.

8. The absorbent article as described in any one of claims 1 to 3, characterized in that: The width of the adhesive placement portion in the second bonding region is less than or equal to the width of the adhesive placement portion in the first bonding region.

9. The absorbent article as claimed in claim 8, characterized in that: The ratio of the width of the adhesive configuration portion in the second bonding region to the width of the adhesive configuration portion in the first bonding region is 20% or more and 100% or less.

10. The absorbent article according to any one of claims 1 to 3, characterized in that: When the area where the first joining region and the second joining region overlap in a top view is taken as the overlapping region, The ratio of the area of ​​the overlapping region to the area of ​​the first joining region is more than 30% and less than 90%.

11. The absorbent article according to any one of claims 1 to 3, characterized in that: When the area where the first joining region and the second joining region overlap in a top view is taken as the overlapping region, The ratio of the area of ​​the overlapping region to the area of ​​the second joining region is more than 20% and less than 80%.

12. The absorbent article according to any one of claims 1 to 3, characterized in that: At least one of the first and second bonding regions includes an adhesive non-distribution portion whose width when the elastic member is stretched is greater than the width when the elastic member is contracted.

13. The absorbent article as claimed in claim 12, characterized in that: When the width of the adhesive non-positioned portion when the elastic member is stretched is W, and the width of the adhesive non-positioned portion when the elastic member is contracted is W', the ratio of W' to W (W' / W) is 20% or more and 90% or less.

14. The absorbent article according to any one of claims 1 to 3, characterized in that: In at least one of the second and third pieces, the constituent fibers are oriented in the transverse direction, and the ring compression strength when compressed in a direction orthogonal to the orientation direction is 7.0 cN or less.

15. The absorbent article as claimed in claim 14, characterized in that: The ring compression strength of the third piece is less than that of the second piece.

16. The absorbent article as claimed in claim 14, characterized in that: The ring compression strength of the first piece is above 1.0 cN and below 7.0 cN.

17. The absorbent article as claimed in claim 14, characterized in that: The ring compression strength of the second piece is above 1.0 cN and below 7.0 cN.

18. The absorbent article as claimed in claim 14, characterized in that: The ring compression strength of the third piece is above 0.5 cN and below 6.0 cN.

19. The absorbent article according to any one of claims 1 to 3, characterized in that: The weight of the third piece is lower than that of the second piece.

20. The absorbent article as claimed in claim 19, characterized in that: The weight of the first piece is 5g / m³. 2 Above and 40g / m 2 the following.

21. The absorbent article as claimed in claim 19, characterized in that: The second piece has a weight of 5g / m³. 2 Above and 30g / m 2 the following.

22. The absorbent article as claimed in claim 19, characterized in that: The third piece has a weight of 5g / m³. 2 Above and 25g / m 2 the following.

23. The absorbent article as claimed in claim 19, characterized in that: The density of the third piece is lower than that of the second piece.

24. The absorbent article as claimed in claim 23, characterized in that: The density of the first piece is 30 × 10⁻⁶. -6 g / mm 3 Above and 300×10 -6 g / mm 3 the following.

25. The absorbent article as claimed in claim 23, characterized in that: The density of the second piece is 30×10. -6 g / mm 3 Above and 200×10 -6 g / mm 3 the following.

26. The absorbent article as claimed in claim 23, characterized in that: The density of the third piece is 30 × 10⁻⁶. -6 g / mm 3 Above and 180×10 -6 g / mm 3 the following.

27. The absorbent article according to any one of claims 1 to 3, characterized in that: At least one of the second and third pieces has a fiber layer containing curled fibers.

28. The absorbent article as claimed in claim 27, characterized in that: The proportion of the curled fibers in the fiber layer containing curled fibers is more than 10% by mass and less than 100% by mass relative to the total mass of the fibers in the fiber layer.

29. The absorbent article as claimed in claim 27, characterized in that: In the third piece, the fiber layer forming the non-skin-facing side contains curled fibers, while the fiber layer forming the skin-facing side does not contain these curled fibers.

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