Pants-type absorbent article

Abstract

To achieve both excellent wearing feeling of an underpants type absorbent article, and easiness in tearing at disposal and prevention of transverse fissure.SOLUTION: An exterior body of an underpants type absorbent article comprises an abdominal side part, a back side part, and a pair of side connection parts in which a side edge portion in the lateral direction of the abdominal side part, and a side edge portion in the lateral direction of the back side part are connected each other. At least one of the abdominal side part and the back side part of the exterior body includes a first shrinkage part where a plurality of elastic members extending in the lateral direction are arranged, and a second shrinkage part where a plurality of elastic members extending in the lateral direction are arranged, and which is continuous to the first shrinkage part in the longitudinal direction, and is positioned at a leg opening part side in the longitudinal direction from the first shrinkage part. A first shrinkage force as an average shrinkage force per unit width in the lateral direction of the first shrinkage part is higher than a second shrinkage force as an average shrinkage force per unit width in the lateral direction of the second shrinkage part. There is provided a reinforcement sheet which is arranged at least in the second shrinkage part in the longitudinal direction of the pair of side connection parts, and is connected by the pair of side connection parts together with the side edge portion of the abdominal side part and the side edge portion of the back side part.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to pants-type absorbent articles such as disposable diapers. [Background technology]

[0002] A pants-type absorbent article generally comprises an absorbent main body, an outer body, and a side joint portion (side seal portion) where the ventral outer body and the dorsal outer body are joined at their side edges. The waist portion of the pants-type absorbent article is formed by joining the ventral outer body and the dorsal outer body at the side joint portion. On the other hand, after wearing a pants-type absorbent article, the side joints are sometimes torn off and discarded for reasons of hygiene, etc. For this reason, the side joints are required to have a function that does not come off during the donning action (when putting on the pants-type absorbent article) or while wearing the article, but can be easily torn off when discarding the article.

[0003] To prevent pants-type absorbent articles such as disposable diapers from slipping down and to improve comfort, it is useful to increase the contractile force of the area from the iliac crest to the anterior superior iliac spine of the wearer (i.e., a narrow area in terms of body shape, where bones are located close to the surface of the body and where there is little skin movement). Also, to prevent pants-type absorbent articles from slipping down and to improve comfort, it is useful to reduce the contractile force of the area below the above area (i.e., an area where the skin stretches greatly with changes in the wearer's posture) so that the diaper does not fit too tightly. Patent Document 1 discloses a pants-type absorbent article in which the contractile force is weakened by widening the spacing between gathers.

[0004] Patent Document 2 discloses a pants-type absorbent article that has a wider gathering pitch in the hip bone area to improve breathability. Patent Document 3 discloses a pants-type absorbent article that can be easily torn apart when discarded by disposing of it in a quantity of a bond strength reducer that corresponds to the number of layers. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2009-125087 [Patent Document 2] Japanese Patent Publication No. 2020-103562 [Patent Document 3] Japanese Patent Application Laid-Open No. 2009-148465 Summary of the Invention [Problem to be solved by the invention]

[0006] The outer body is made of a soft material to improve comfort and texture. When tearing the side seam of an outer body made of a soft material at the time of disposal, the torn side shrinks significantly in the area with a wide gather spacing (i.e., the area with weak contraction force), and the force that tears the seam acts in the width direction, which can cause the outer body to tear horizontally.

[0007] The present invention relates to a pants-type absorbent article that is comfortable to wear, easy to tear when disposed of, and prevents lateral tearing. [Means for solving the problem]

[0008] A pants-type absorbent article according to one embodiment of the present disclosure comprises: A pants-type absorbent article comprising an absorbent main body, and an outer body including a plurality of thermoplastic sheets and disposed on the non-skin side of the absorbent main body, the outer body having a waist opening and a pair of leg openings, the article having a vertical direction extending from the wearer's abdomen side through the crotch region to the back side, and a horizontal direction perpendicular to the vertical direction, The outer casing is a ventral portion disposed on the ventral side of the wearer; a back portion disposed on the back of the wearer; a pair of side joint portions at which side edges in the lateral direction of the ventral portion and side edges in the lateral direction of the dorsal portion are joined, At least one of the ventral side portion and the dorsal side portion of the exterior body is a first contraction portion in which a plurality of elastic members extending in the transverse direction are arranged; a second contracted portion in which a plurality of elastic members extending in the horizontal direction are arranged, the second contracted portion is continuous with the first contracted portion in the vertical direction, and is located closer to the leg opening in the vertical direction than the first contracted portion, a first contraction force, which is an average contraction force per unit width in the horizontal direction of the first contraction portion, is higher than a second contraction force, which is an average contraction force per unit width in the horizontal direction of the second contraction portion, the unit width being a width in the vertical direction; A reinforcing sheet is provided which is arranged at least in the second contracted portion in the longitudinal direction of the pair of side joints and is joined by the pair of side joints together with the side edge portions of the ventral portion and the side edge portions of the dorsal portion.

[0009] The pants-type absorbent article of the present invention can achieve both good comfort when worn, ease of tearing when disposed of, and prevention of lateral tearing. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a schematic perspective view showing a pants-type absorbent article according to an embodiment of the present invention. [Figure 2] This is a schematic plan view showing the skin-facing side of the pants-type absorbent article, and shows the pants-type absorbent article unfolded and the elastic members of each part stretched to spread it out flat. [Figure 3] FIG. 3 is a schematic plan view showing a side joining portion of the pants-type absorbent article. [Figure 4] FIG. 10 is a schematic cross-sectional view of the side joint, showing one of the ventral and dorsal portions. [Figure 5] 1 shows a schematic view of a person wearing the pants-type absorbent article. [Figure 6] 10 shows an example of the configuration of a reinforcing sheet joint. [Figure 7] 1 shows an example of a pattern of a plurality of high density portions of an outer layer sheet and an inner layer sheet. [Figure 8] 1 shows an example of a pattern of a plurality of high density portions of an outer layer sheet and an inner layer sheet. [Figure 9]An example of the fiber orientation degree of the outer layer sheet and the inner layer sheet is shown below. [Figure 10] 1 shows a configuration example of an exterior body according to a first modification. [Figure 11] 10 shows a configuration example of an exterior body according to Modification 2. [Figure 12] 10 shows a configuration example of an exterior body according to Modification 3. [Figure 13] 10 shows a configuration example of an exterior body according to a fourth modification. [Figure 14] Examples of coating patterns for reinforcing sheet joints and joint strength reduced areas are shown below. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0012] [Overall structure of pants-type disposable diapers] 1 and 2 show a pants-type disposable diaper 1 as a pants-type absorbent article according to an embodiment of the present invention. The pants-type disposable diaper 1 will be referred to as the diaper 1 hereinafter.

[0013] As shown in FIG. 1, the diaper 1 has a waist opening 1W and a pair of leg openings 1L, and is worn around the waist and crotch area of ​​a wearer. The waist opening 1W has a waist opening edge Wa. The diaper 1 has a longitudinal direction X and a lateral direction Y. The longitudinal direction X extends from the wearer's abdominal side through the crotch area to the back side. The lateral direction Y is perpendicular to the longitudinal direction X and corresponds to the left-right direction of the wearer. Furthermore, as shown in FIG. 2 and other figures, the direction perpendicular to the longitudinal direction X and the lateral direction Y of the diaper 1 is defined as a thickness direction Z. In this specification, the "waist side" means the side closer to the waist opening end Wa of the waist opening 1W in the vertical direction X, and the "leg side" means the side farther from the waist opening end Wa in the vertical direction X. In this specification, "inner side in the lateral direction Y" means the side in the lateral direction Y that is closer to the vertical center line CL that divides the pants-type absorbent article (diaper 1) into two equal parts in the lateral direction Y, and "outer side in the lateral direction Y" means the side that is away from the vertical center line CL. In this specification, with respect to the thickness direction Z, the side of the pant-type absorbent article (diaper 1) that is closest to the wearer's skin when worn may be referred to as the skin side, and the side that is closest to the clothing may be referred to as the non-skin side. Furthermore, the "skin-facing side" refers to the side of the pant-type absorbent article (diaper 1) or its constituent member that faces the wearer's skin, i.e., the side that is relatively close to the wearer's skin. The "non-skin-facing side" refers to the side of the pant-type absorbent article (diaper 1) or its constituent member that faces the opposite side (clothing side) from the skin-facing side, i.e., the side that is relatively far from the wearer's skin.

[0014] When a wearer puts on the diaper 1, first, the wearer puts his / her legs through the pair of leg openings 1L, pulls the diaper 1 up towards the wearer's torso, and places the diaper 1 around the wearer's waist and crotch area. In this specification, this series of actions is referred to as the "putting action." The putting action may be performed by a caregiver rather than the wearer of the diaper 1. For this reason, in this specification, the subject of the putting action is referred to as the "caregiver, etc." In this specification, the state in which the diaper 1 is placed in the proper wearing position that is normally assumed by a wearer is referred to as "when worn."

[0015] As shown in FIGS. 1 and 2, the diaper 1 includes an absorbent main body 4 and an exterior body 5 disposed on the non-skin-facing side of the absorbent main body 4. 2 shows the diaper 1 unfolded and laid out flat to the designed dimensions with the elastic members of each section stretched and completely excluding the influence of the elastic members. This state is also referred to as the "unfolded and stretched state" of the diaper 1. Unfolding the diaper 1 means separating the ventral side section 5a and the dorsal side section 5b of the side seam 8, which will be described later.

[0016] The absorbent main body 4 is fixed to the skin-facing side of the exterior body 5. The absorbent main body 4 has at least the absorbent body 40, and may further have a topsheet 2, a backsheet (not shown), etc. For example, the absorbent main body 4 has a configuration in which the backsheet, the absorbent body 40, and the topsheet 2 are laminated in the thickness direction Z. The absorbent body 40 includes a liquid-retaining absorbent core, and may further include a core wrap sheet that covers the absorbent core. The absorbent main body 4 has, as both ends in the longitudinal direction X, an absorbent main body ventral end portion 4A that is located on the wearer's ventral side, and an absorbent main body dorsal end portion 4B that is located on the wearer's dorsal side. Materials used for each component included in the absorbent body 4 (back sheet, absorbent body 40, top sheet 2, etc.) can be any material used in the relevant technical field without any particular restrictions.

[0017] The exterior body 5 includes a plurality of thermoplastic sheets 50. The exterior body 5 is configured as a laminate of a plurality of thermoplastic sheets 50, for example. The thermoplastic sheet 50 is a sheet material mainly made of a thermoplastic resin. The thermoplastic sheet 50 preferably contains 90% by mass or more of a thermoplastic resin, and more preferably is made of 100% by mass of a thermoplastic resin. Examples of thermoplastic resins include polyolefins such as polyethylene and polypropylene; polyesters such as polyethylene terephthalate; polyamides such as nylon 6 and nylon 66; polyacrylic acid, polymethacrylic acid alkyl esters, polyvinyl chloride, and polyvinylidene chloride. These may be used alone or in combination of two or more. The thermoplastic fibers may be short or long fibers. Examples of thermoplastic fibers that may be used include core-sheath or side-by-side composite fibers, split fibers, modified cross-section fibers, and heat-shrinkable fibers.

[0018] The exterior body 5 has at least a ventral portion 5a arranged on the ventral side of the wearer and a dorsal portion 5b arranged on the dorsal side of the wearer. In this embodiment, the exterior body 5 further includes a crotch portion 5c located between the ventral portion 5a and the dorsal portion 5b and arranged in the crotch area of ​​the wearer. In this example, the ventral portion 5a, the crotch portion 5c, and the dorsal portion 5b are arranged along the longitudinal direction X. Furthermore, the exterior body 5 has a shape in which the crotch portion 5c is narrowed inward in the lateral direction Y. This forms leg openings 1L (see FIG. 1) that fit the wearer's leg openings. The outer edge of the exterior body 5 is preferably configured to be line-symmetric (bilaterally symmetric) with respect to the vertical center line CL.

[0019] Furthermore, the exterior body 5 has a pair of side joints 8, each formed by joining a side edge 5d of the ventral portion 5a in the lateral direction Y to a side edge 5e of the dorsal portion 5b in the lateral direction Y. That is, the right side joint 8 is formed by joining the right side edge 5d of the ventral portion 5a to the right side edge 5e of the dorsal portion 5b in the thickness direction Z. The left side joint 8 is formed by joining the left side edge 5d of the ventral portion 5a to the left side edge 5e of the dorsal portion 5b in the thickness direction Z. As will be described in detail later, the side joints 8 are preferably joined by heat sealing, ultrasonic sealing or the like.

[0020] [Contraction section] As shown in Fig. 2, at least one of the abdominal portion 5a and the back portion 5b of the exterior body 5 includes a fourth contractible portion 204, a first contractible portion 201, a second contractible portion 202, and a third contractible portion 203. At least one of the abdominal portion 5a and the back portion 5b is divided into four band-like regions extending in the lateral direction Y, and the four band-like regions are designated, in order from the waist opening 1W toward the leg openings 1L, as the fourth contractible portion 204, the first contractible portion 201, the second contractible portion 202, and the third contractible portion 203. A plurality of elastic members 10 extending in the lateral direction Y are arranged in each of the fourth contractible portion 204, the first contractible portion 201, the second contractible portion 202, and the third contractible portion 203.

[0021] The fourth contracted portion 204 is a region extending in the longitudinal direction X from the uppermost elastic member 10 closest to the waist opening edge Wa of the waist opening 1W to the ventral end 4A of the absorbent main body or the dorsal end 4B of the absorbent main body. The first contracted portion 201 is continuous with the fourth contracted portion 204 in the longitudinal direction and is located closer to the leg opening 1L in the longitudinal direction X than the fourth contracted portion 204. The second contracted portion 202 is continuous with the first contracted portion 201 in the longitudinal direction and is located closer to the leg opening 1L in the longitudinal direction X than the first contracted portion 201. The third contracted portion 203 is continuous with the second contracted portion 202 in the longitudinal direction and is located closer to the leg opening 1L in the longitudinal direction X than the second contracted portion 202. The lower end of the third contracted portion 203 in the longitudinal direction X (the end closest to the crotch portion 5c) is the lowermost elastic member 10 closest to the leg end 8b. The first contracted portion 201, the second contracted portion 202, and the third contracted portion 203 are defined by dividing the distance from the lower end of the fourth contracted portion 204 (i.e., the ventral end 4A or the dorsal end 4B of the absorbent main body) to the lower end of the third contracted portion 203 (the end closer to the crotch portion 5c) into thirds. The length (width) in the vertical direction X of the fourth contracted portion 204 may be the same as or different from that of the first contracted portion 201, the second contracted portion 202, and the third contracted portion 203. Note that in the drawings, the ratios of the lengths (widths) in the vertical direction X of the fourth contracted portion 204, the first contracted portion 201, the second contracted portion 202, and the third contracted portion 203 may not be consistent between multiple drawings, and the drawings are merely schematic and are for illustrative purposes only.

[0022] The first contraction force, which is the average contraction force per unit width in the lateral direction Y of first contraction portion 201, is higher than the fourth contraction force, which is the average contraction force per unit width in the lateral direction Y of fourth contraction portion 204. The first contraction force of first contraction portion 201 is higher than the second contraction force, which is the average contraction force per unit width in the lateral direction Y of second contraction portion 202. The third contraction force, which is the average contraction force per unit width in the lateral direction Y of third contraction portion 203, is higher than the second contraction force of second contraction portion 202.

[0023] The elastic members 10 are arranged in the lateral direction Y in each of the fourth contraction section 204, the first contraction section 201, the second contraction section 202, and the third contraction section 203. The elastic members 10 are bonded in a stretched state between the outer sheet 51 and the inner sheet 52 with an adhesive such as a hot melt adhesive. Methods for varying the average contractile force per unit width of each contraction section include varying the number, material, and thickness of the elastic members 10 used in each contraction section, varying the elongation rate of the elastic members, or a combination of these methods.

[0024] 2, the average contractile force per unit width of each contractile section is made different by varying the intervals between the elastic members 10 arranged in the fourth contractile section 204, the first contractile section 201, the second contractile section 202, and the third contractile section 203. That is, the elastic members 10 are arranged at relatively narrow intervals in the first contractile section 201 and the third contractile section 203, which have a relatively high average contractile force per unit width. On the other hand, the elastic members 10 are arranged at relatively wide intervals in the fourth contractile section 204 and the second contractile section 202, which have a relatively low average contractile force per unit width.

[0025] In the diaper 1 of this embodiment, the first contracted portion 201 is a region that contacts the area from the iliac crest 9a to the anterior superior iliac spine 9b of the wearer when the diaper 1 is worn, as shown in Fig. 5, and the third contracted portion 203 is a region that contacts the area where the trochanter 9c of the wearer is located when the diaper 1 is worn. In Fig. 5, the symbol 9d indicates the ischium. Since the first average contraction force per unit width of the first contraction portion 201 and the third average contraction force per unit width of the third contraction portion 203 are each higher than the second average contraction force per unit width of the second contraction portion 202, the first contraction portion 201 can tightly tighten the area from the iliac crest 9a to the anterior superior iliac spine 9b, and the third contraction portion 203 can tightly tighten the area where the trochanter 9c is located, thereby achieving excellent anti-slip performance.

[0026] In this way, excellent anti-slip performance is obtained by the first contraction portion 201 and the third contraction portion 203, so that the second average contraction force per unit width of the second contraction portion 202 and the fourth average contraction force per unit width of the fourth contraction portion 204 can be reduced.

[0027] The part of the wearer that the second contraction portion 202 abuts is a part where the skin expands and contracts greatly when the wearer changes posture. For example, when the wearer changes from a standing position to a crawling position, the skin in that part expands greatly. Therefore, by lowering the second average contractile force per unit width of the second contractile portion 202 and not fitting the diaper too tightly in areas where the skin stretches greatly, slip-off due to skin stretching can be prevented, further improving slip-off prevention performance. Also, by not fitting the diaper too tightly in areas where the skin stretches greatly, wearing comfort is further improved and elastic marks and redness on the wearer's skin can be prevented.

[0028] Furthermore, by lowering the fourth average contractile force per unit width of the fourth contractile portion 204, it is possible to prevent the abdomen, which is bulging forward, from being left with rubber marks or from becoming red, and since the waist opening end Wa is easy to open, it becomes easier to put on the diaper 1.

[0029] From the viewpoint of improving slip-down prevention performance and comfort, the first average contraction force per unit width of the first contraction portion 201 is preferably 2.0 to 9.0 cN / mm, particularly 2.0 to 7.0 cN / mm, and the second average contraction force per unit width of the second contraction portion 202 is preferably 0.4 to 6.0 cN / mm, particularly 0.4 to 3.5 cN / mm. The difference between the first average contraction force per unit width of the first contraction portion 201 and the second average contraction force per unit width of the second contraction portion 202 is more than 0 cN / mm, preferably 0.2 to 6.0 cN / mm, particularly 0.2 to 3.0 cN / mm. Furthermore, from the viewpoint of improving slip-off prevention performance and comfort, the third average contraction force per unit width of the third contraction portion 203 is preferably 2.0 to 9.0 cN / mm, particularly 2.0 to 7.0 cN / mm, and the difference between the third average contraction force per unit width of the third contraction portion 203 and the second average contraction force per unit width of the second contraction portion 202 is more than 0 cN / mm, preferably 0.2 to 6.0 cN / mm, particularly preferably 0.2 to 3.0 cN / mm.

[0030] Furthermore, from the viewpoint of preventing the wearer from leaving rubber marks or redness on their skin and from the viewpoint of ease of putting on (ease of putting on), the fourth average contractile force per unit width of the fourth contractile portion 204 is preferably 0.2 to 9.0 cN / mm, particularly 0.2 to 4.0 cN / mm, and the difference between the first average contractile force per unit width of the first contractile portion 201 and the fourth average contractile force per unit width of the fourth contractile portion 204 is more than 0 cN / mm, and is preferably 0.2 to 6.0 cN / mm, particularly 0.4 to 3.0 cN / mm.

[0031] [Method for measuring the contractile force of each contractile portion] The diaper 1 is unfolded and spread out flat as shown in Figure 2, and then cut along straight lines parallel to the lateral direction Y to cut out the fourth contractile portion 204, the first contractile portion 201, the second contractile portion 202, and the third contractile portion 203 from each of the ventral portion 5a and the dorsal portion 5b. When cutting out the portions, not only the outer cover 5 but also the entire diaper 1 including the absorbent body 4 and the like is cut. The longitudinal ends (immediately inside the portions that formed the side seal portions) of each cut-out shrinkable portion (measurement sample) are clamped in the chucks of a Tensilon tensile tester (ORIENTEC Corporation, "RTC-1210A"), and the measurement sample is stretched longitudinally at a speed of 300 mm / min. The inner dimension of the outer packaging body 5 is defined as the length between the side seal portions of the outer packaging body 5 measured when the outer packaging material sheet is not shrunk by the elastic member (in other words, when only the outer packaging material is stretched without the elastic member). When the inner dimension of the outer packaging body 5 is 100 (e.g., 350 mm), the sample is stretched to a length equivalent to 80 (e.g., 280 mm), and then shrunk to a length equivalent to 71 (e.g., 250 mm) at a speed of 300 mm / min, and the tensile load (cN) is defined as the shrinkage force. The reason for specifying the return force at a length equivalent to 71 when the inner dimension of the outer cover 5 is 100 is because the abdominal circumference of infants, who are the primary target audience for the diaper 1 of this embodiment, is approximately 71% of the inner dimension of the diaper 1. The abdominal circumference referred to here is the average abdominal circumference measured in a standing and sitting position, taking into account changes in abdominal circumference when the infant changes posture. The average contractile force per unit width is calculated by dividing the measured contractile force by the measured width (cut width).

[0032] [Side joint configuration] As shown in FIG. 2, the pair of side joining portions 8 have a waist end portion 8a and a leg end portion 8b which constitute both ends in the longitudinal direction X, respectively. The waist end portion 8a is the end portion of the side joining portion 8 on the waist side. The leg end 8b is the end of the side joint 8 on the leg side. Each side joining portion 8 has a configuration that extends in the longitudinal direction X as a whole from a waist end portion 8a to a leg end portion 8b.

[0033] A pair of side joining portions 8, each extending from the waist end portion 8a to the leg end portion 8b, form the abdominal portion 5a and the back portion 5b into a tubular shape that conforms to the wearer's waist circumference, thereby forming the waist opening 1W and leg openings 1L of the diaper 1. It is preferable that the side joining portions 8 maintain the abdominal portion 5a and the back portion 5b joined together without separating them during the putting action and while the diaper is being worn. In this specification, the unintentional separation of the abdominal side portion 5a and the dorsal side portion 5b of the side joint portion 8 during the donning action and while the diaper 1 is being worn is referred to as "peeling off." On the other hand, when changing the diaper 1 after wearing it, in order to hygienically dispose of excrement adhering to the diaper 1, a caregiver or the like may separate the ventral portion 5a and the dorsal portion 5b of the side joint portion 8, unfold the diaper 1, and then discard it. In this specification, the action of intentionally separating the ventral portion 5a and the dorsal portion 5b of the side joint portion 8 by applying an external force to the side joint portion 8 and / or its surroundings when disposing of the diaper 1 is referred to as "tearing." In this way, it is preferable that the side joining portions 8 have a structure that can prevent peeling during the putting action and while wearing the garment, and can be easily torn without tearing laterally when discarding.

[0034] [Example of exterior body configuration] 4, the exterior body 5 preferably includes a plurality of thermoplastic sheets 50, such as an outer layer sheet 51 and an inner layer sheet 52. The outer layer sheet 51 is disposed closer to the skin than the inner layer sheet 52, and constitutes the non-skin-facing surface of the exterior body 5. An elastic member 10, which will be described later, is preferably disposed between the inner layer sheet 52 and the outer layer sheet 51.

[0035] As described above, at least one of the ventral portion 5a or the dorsal portion 5b of the outer body 5 includes, in order from the waist opening 1W toward the leg openings 1L, a fourth contraction portion 204 (having a relatively low average contraction force per unit width), a first contraction portion 201 (having a relatively high average contraction force per unit width), a second contraction portion 202 (having a relatively low average contraction force per unit width), and a third contraction portion 203 (having a relatively high average contraction force per unit width).

[0036] When the diaper 1 is disposed of, if the side joint portion 8 of the outer casing 5 is torn in the vertical direction X from the waist end portion 8a toward the leg end portion 8b, when the first contraction portion 201 (where the elastic members 10 are arranged at relatively close intervals and the average contraction force per unit width is relatively high) has finished being torn and the second contraction portion 202 (where the elastic members 10 are arranged at relatively wide intervals and the average contraction force per unit width is relatively low) begins to be torn, the first contraction portion 201 may contract significantly, and a force tearing the side joint portion 8 in the vertical direction X may act in the horizontal direction Y, causing the second contraction portion 202 to tear laterally in the horizontal direction Y.

[0037] Therefore, in this embodiment, at least one of the ventral portion 5a or the dorsal portion 5b of the outer casing 5 has a reinforcing sheet that reinforces the second contraction portion 202 (in which the elastic members 10 are arranged at relatively wide intervals and the average contraction force per unit width is relatively low).

[0038] [Example of reinforcement sheet configuration] The reinforcing sheet is formed by a folded portion 100 in which an end 103 in the longitudinal direction X of the exterior body 5 is folded back in the longitudinal direction X from the waist opening end Wa. Hereinafter, the reinforcing sheet will be referred to as the folded portion 100, which means that the reinforcing sheet and the folded portion 100 are the same thing. As shown in FIG. 4 , the folded portion 100 is formed by folding back an end 103 in the longitudinal direction X of the outer layer sheet 51 of the exterior body 5 in the longitudinal direction X from the waist opening end Wa on the waist opening 1W side toward the skin in the longitudinal direction X toward the crotch part 5c. The folded portion 100 faces the inner layer sheet 52 of the exterior body 5.

[0039] The folded portion 100 is disposed at least in the second contracted portion 202 in the longitudinal direction X of the pair of side joints 8. Preferably, the folded portion 100 is disposed so as to continuously cover at least the first contracted portion 201 and the second contracted portion 202 in the longitudinal direction X of the pair of side joints 8. The folded portion 100 may be disposed at least over both ends 202a, 202b in the longitudinal direction X of the second contracted portion 202 in the longitudinal direction X of the pair of side joints 8. By reinforcing the second contracted portion 202, even if the first contracted portion 201 contracts significantly when tearing of the first contracted portion 201 (which has a relatively high average contractile force per unit width) is completed and tearing of the second contracted portion 202 (which has a relatively low average contractile force per unit width) begins, the reinforced second contracted portion 202 prevents the second contracted portion 202 from tearing laterally in the transverse direction Y.

[0040] Preferably, the folded-back portion 100 is arranged in the longitudinal direction X so as to straddle both ends 202a, 202b of the second contracted portion 202 in the longitudinal direction X. Preferably, the folded-back portion 100 is arranged so as to continuously cover at least the first contracted portion 201 and the second contracted portion 202 in the longitudinal direction X of the pair of side joint portions 8. This allows the reinforced first contracted portion 201 to mitigate large contractions of the first contracted portion 201 when tearing is completed and tearing of the second contracted portion 202 (which has a relatively high average contraction force per unit width) begins, while the reinforced second contracted portion 202 prevents the second contracted portion 202 from tearing laterally in the transverse direction Y. Furthermore, since the folded-back portion 100 is laminated on both the first contracted portion 201 and the second contracted portion 202 that are continuous in the vertical direction X and the number of laminated layers does not change, it is easy to tear continuously in the vertical direction X from the first contracted portion 201 to the second contracted portion 202.

[0041] In this example, the folded-back portion 100 is arranged in the longitudinal direction X of the pair of side joint portions 8 to cover the fourth contracted portion 204, the first contracted portion 201, and the second contracted portion 202, and to cover the region 203a of the third contracted portion 203 that is adjacent to the second contracted portion 202. Because the folded-back portion 100 is arranged to cover the first contracted portion 201 and the second contracted portion 202 from the fourth contracted portion 204 (i.e., the start of tearing) at the waist opening end Wa, and to cover the region 203a of the third contracted portion 203 that is adjacent to the second contracted portion 202, the side joint portions 8 can be easily torn continuously in the longitudinal direction X from the waist end portion 8a toward the leg end portion 8b.

[0042] The folded-back portion 100 is arranged so as to cover at least the second contracted portion 202 in the lateral direction Y across the pair of side joint portions 8. In this example, the folded-back portion 100 is arranged so as to cover the fourth contracted portion 204, the first contracted portion 201, and the second contracted portion 202 in the lateral direction Y across the pair of side joint portions 8, and to cover a region 203a of the third contracted portion 203 adjacent to the second contracted portion 202. The folded-back portion 100 is joined by the pair of side joint portions 8 together with a side edge 5d in the lateral direction Y of the ventral portion 5a and a side edge 5e in the lateral direction Y of the dorsal portion 5b.

[0043] In this way, both ends of the folded portion 100 in the horizontal direction Y are joined to the exterior body 5 by a pair of side joints 8, and one end in the vertical direction X is continuous with the end 103 of the exterior body 5. That is, the position of the folded portion 100 relative to the exterior body 5 is fixed by three sides, namely the pair of side joints 8 and the end 103 of the exterior body 5. Therefore, even if the folded portion 100 is not joined to the inner layer sheet 52 of the exterior body 5 in a planar manner, the position of the folded portion 100 relative to the exterior body 5 is fixed. On the other hand, as described below, the folded portion 100 may be joined to the inner layer sheet 52 of the exterior body 5 in a planar manner.

[0044] [Example of reinforcement sheet joint configuration] The folded portion 100 has a reinforcing sheet joining portion 101 where the folded portion 100 is joined to the exterior body 5. The reinforcing sheet joining portion 101 is formed, for example, by a plurality of seal portions or a hot melt adhesive. The seal portions are joined, for example, by pressure means and / or heating means, and more specifically, by heat sealing or ultrasonic sealing. As the hot melt adhesive, for example, a styrene-based (SIS, SBS, SEBS) or polyolefin-based material can be used.

[0045] Figure 6 shows examples of the configuration of the reinforcing sheet joint portion. Figure 6A shows an example in which the reinforcing sheet joint portion 101 is composed of multiple seal portions. Figure 6B, C, and D show examples in which the reinforcing sheet joint portion 101 is composed of a hot melt adhesive.

[0046] The reinforcing sheet joints 101 are arranged (A, B, C, D) inside the second contraction portion 202 in the longitudinal direction X. By joining the folded-back portion 100 to the ventral portion 5a or the dorsal portion 5b of the exterior body 5 not only by the side joints 8 but also by the reinforcing sheet joints 101 in a planar manner, the strength of the second contraction portion 202 joined to the folded-back portion 100 is increased, making the second contraction portion 202 even less susceptible to lateral tearing.

[0047] The reinforcing sheet joints 101 are preferably arranged so as to include a component in the longitudinal direction X. For example, the reinforcing sheet joints 101 are arranged such that seal portions extending in the longitudinal direction X are spaced apart in the transverse direction Y (A). Alternatively, the reinforcing sheet joints 101 are arranged in a wave-like shape including straight or curved lines including a component in the longitudinal direction X (B, D). Alternatively, the reinforcing sheet joints 101 are arranged in a spiral shape including a curved line including a component in the longitudinal direction X (C). Here, the spiral shape refers to a shape in which multiple unit shapes, each of which is a circle or ellipse, are repeatedly arranged along the transverse direction Y. By arranging the reinforcing sheet joints 101 so as to include a component in the longitudinal direction X, the strength of the second contraction portion 202 in the longitudinal direction X is increased. Even if the second contraction portion 202 were to tear laterally in the transverse direction Y, the joints with the reinforcing sheet joints 101, which have high strength, prevent transverse tearing. This makes the second contraction portion 202 less susceptible to transverse tearing overall.

[0048] Preferably, the reinforcing sheet joint portion 101 is arranged on the exterior body 5 so as to straddle both ends 202a, 202b in the longitudinal direction X of the second contraction portion 202 (C, D). In other words, the reinforcing sheet joint portion 101 is arranged from the region of the first contraction portion 201 adjacent to the second contraction portion 202 to the region 203a of the third contraction portion 203 adjacent to the second contraction portion 202, so as to straddle both ends 202a, 202b in the longitudinal direction X of the second contraction portion 202. As a result, when the first contracted portion 201 (which has a relatively high average contractile force per unit width) has finished tearing and the second contracted portion 202 (which has a relatively low average contractile force per unit width) begins to tear, the reinforcing sheet joint portions 101 are located across both ends 202a, 202b of the second contracted portion 202 in the longitudinal direction X, and thus pleats are formed in the longitudinal direction X when the first contracted portion 201 contracts significantly, strengthening the joint in the longitudinal direction X and making it easier for the second contracted portion 202 to tear continuously in the longitudinal direction X. Furthermore, the reinforcing sheet joint portions that include a component in the longitudinal direction X can increase the strength of the material in the transverse direction Y. This makes the second contracted portion 202 even less susceptible to lateral tearing.

[0049] As shown in FIG. 4 , more preferably, the reinforcing sheet joint portion 101 is disposed in the longitudinal direction X across both ends of the folded-back portion 100. As described above, in this example, the folded-back portion 100 is disposed in the longitudinal direction X of the pair of side joint portions 8 so as to cover the fourth contracted portion 204, the first contracted portion 201, and the second contracted portion 202, and to cover the region 203a of the third contracted portion 203 adjacent to the second contracted portion 202. Therefore, the reinforcing sheet joint portion 101 is disposed in the longitudinal direction X from the waist opening end Wa of the folded-back portion 100 to the end portion 103. As a result, the folded-back portion 100 is laminated on both the first contracted portion 201 and the second contracted portion 202, which are continuous in the longitudinal direction X, so that the number of laminated layers does not change, and the folded-back portion 100 is bonded entirely across the longitudinal direction X, making it easy to tear continuously in the longitudinal direction X from the first contracted portion 201 to the second contracted portion 202.

[0050] In cases where the reinforcing sheet joint portion 101 is made of a hot melt adhesive (B, C, D), the reinforcing sheet joint portion 101 is applied to the folded portion 100, not to the inner layer sheet 52 of the exterior body 5 that faces the folded portion 100. When the exterior body 5 including the outer layer sheet 51 and the inner layer sheet 52 is compared with the folded portion 100 made of the outer layer sheet 51, the breaking strength of the folded portion 100 is lower. In order to prevent the folded portion 100, which has low breaking strength, from breaking due to actions such as putting on the product, the reinforcing sheet joint portion 101 can be applied to the folded portion 100 to increase the breaking strength of the folded portion 100.

[0051] Whether the adhesive is applied to the folded portion 100 or the inner layer sheet 52 of the exterior body 5 facing the folded portion 100 can be determined as follows. The folded portion 100, which is joined at the reinforcing sheet joining portion 101, and the inner layer sheet 52 of the exterior body 5 facing the folded portion 100 are peeled away, and the contraction of the elastic member 10 is stretched to an elongated state. A toner that reacts with the adhesive is sprinkled on the joining surfaces. The coated and uncoated portions are binarized based on the presence or absence of the coloring or fluorescence amount of the toner, and the coated area ratio is calculated. The side with a higher area ratio of the coloring or fluorescence amount of the toner is the adhesive coated surface.

[0052] [Side joint] As described above, it is preferable that the side joint portions 8 have a configuration that can prevent peeling during donning and wearing, and can be easily torn without tearing laterally when discarded. From this perspective, at least one of the side joint portions 8 includes multiple side seal portions S. It is preferable that the pair of side joint portions 8 have the same configuration. In this specification, the dimensions and angles of each part are measured in a natural state with the elastic members of each part not stretched, unless otherwise specified.

[0053] The side seal portion S is a portion where the thermoplastic sheets 50 of both the ventral portion 5a and the dorsal portion 5b are fused and joined together. The side seal portion S is joined by, for example, a pressure means and / or a heating means, specifically, by heat sealing or ultrasonic sealing. The side seal portions S are spaced apart in the longitudinal direction X and extend in the lateral direction Y, respectively. Since the multiple side seal portions S are arranged at intervals in the vertical direction X, peeling of the entire side joint portion 8 along the vertical direction X can be prevented even if one side seal portion S peels off. As shown in FIG. 3, the side seal portions S are preferably arranged at equal intervals in the vertical direction X from the viewpoint of stabilizing the joint strength of the entire side joint portion 8.

[0054] "The side seal portion S extends in the horizontal direction Y" means that the dimension of the side seal portion S in the horizontal direction Y is greater than the dimension in the vertical direction X, and therefore the side seal portion S as a whole extends in the horizontal direction Y. In other words, the side seal portion S is not limited to extending parallel to the horizontal direction Y. In the example shown in FIG. 3, the side seal portion S is configured in a rectangular shape extending in the lateral direction Y in a plan view.

[0055] [Example of side seal dimensions] The following examples of dimensions for the side seal portion S can be given from the perspective of achieving both resistance to peeling during donning and donning and ease of tearing. Note that, as mentioned above, the following dimensions are those in their natural state when the elastic member is not stretched. The length of the side seal portion S in the horizontal direction Y is preferably 0.5 mm or more, more preferably 1 mm or more, and is preferably 10 mm or less, more preferably 4 mm or less, and is preferably 0.5 mm or more and 10 mm or less, more preferably 1 mm or more and 4 mm or less. The length of the side seal portion S in the vertical direction X is preferably 0.1 m or more, more preferably 0.3 mm or more, and is preferably 2 mm or less, more preferably 0.6 mm or less, and is preferably 0.1 mm or more and 2 mm or less, more preferably 0.3 mm or more and 0.6 mm or less. The length of the side seal portion S in the horizontal direction Y is preferably 100% or more, more preferably 400% or more, and preferably 1000% or less, more preferably 800% or less, and also preferably 100% or more and 1000% or less, more preferably 400% or more and 800% or less, of the length of the side seal portion S in the vertical direction X. The distance in the vertical direction X between adjacent side seal portions S is preferably 0.1 mm or more, more preferably 1 mm or more, and is preferably 10 mm or less, more preferably 4 mm or less, and is preferably 0.1 mm or more and 10 mm or less, more preferably 1 mm or more and 4 mm or less.

[0056] [Example of elastic member configuration] As shown in FIG. 2, the front side portion 5a and the back side portion 5b of the exterior body 5 include a plurality of elastic members 10 extending in the lateral direction Y. The plurality of elastic members 10 are disposed between the plurality of thermoplastic sheets 50 of the exterior body 5. For example, the plurality of elastic members 10 are disposed between an outer layer sheet 51 and an inner layer sheet (not shown). These elastic members 10 provide stretchability around the waist of the diaper 1, making it easier to put on and maintaining a good fit when worn. Note that "the elastic members 10 extend in the lateral direction Y" means that the elastic members 10 extend in the lateral direction Y in the expanded and stretched state. However, the above expression is not limited to the state in which the elastic members 10 are parallel to the lateral direction Y in the expanded and stretched state, but also includes the state in which the elastic members 10 extend in the lateral direction Y as a whole. Furthermore, as shown in FIG. 2, the exterior body 5 may include, in addition to the elastic members 10, leg elastic members 11 arranged around the leg openings 1L.

[0057] The elastic members 10, 11 can preferably be thread-shaped (such as rubber thread) or string-shaped (such as flat rubber) with a rectangular, square, circular, polygonal, etc. cross section, or multifilament thread-shaped materials, etc. Materials conventionally used for absorbent articles such as disposable diapers can be used without any particular restrictions for the elastic members 10, 11, and examples thereof include synthetic rubbers such as styrene-butadiene, butadiene, isoprene, and neoprene, natural rubber, EVA, stretchable polyolefin, polyurethane, etc.

[0058] In order to ensure stretchability around the entire waist, the outer ends of the elastic members 10 of the abdominal portion 5a and the dorsal portion 5b in the lateral direction Y are preferably located at or near the side joints 8. Specifically, the distance between the ends and the side joints 8 in the lateral direction Y is preferably 20 mm or less, and more preferably the distance is 0 mm and the ends are located within the side joints 8. The elastic member 10 is generally arranged in or near the area where force is applied when tearing, and this tends to affect ease of tearing when discarding.

[0059] The stretch rate of the elastic member 10 means the ratio of the length of the elastic member stretched in the expanded and stretched state of the pant-type absorbent article to the length of the elastic member in its natural length when removed from the pant-type absorbent article. In other words, the lower the elongation rate, the smaller the elastic force when the elastic member 10 is pulled tends to be. The stretch rate of the elastic member 10 can be adjusted during manufacturing by adjusting the degree of stretch of the elastic member 10 placed in the exterior body 5. During manufacturing, for example, the elastic member 10 is stretched to a predetermined length, and adhesive is applied to the elastic member 10 using a comb or the like, and the elastic member 10 is fixed to the thermoplastic sheet 50 of the exterior body 5.

[0060] [Method for measuring the average elongation rate of elastic members] The side joint portions 8 and the side reinforcing portions 105 of the diaper 1 are separated to remove the absorbent main body 4, and the ventral portion 5a and the dorsal portion 5b of the exterior body 5 are cut out. The cut-out portions are then cut parallel to the lateral direction Y to cut out the measurement target portions. The length of the elastic members 10 in each cut-out region is then measured when the diaper 1 is in an expanded and stretched state. From these measurements, the average length of all the elastic members 10 in the outer casing 5 in the maximum stretched state is calculated. The length of the elastic members 10 in the expanded and stretched state may also be measured by measuring the length of the outer casing 5 in the lateral direction Y after removing all the elastic members 10 using the method described below. All of the elastic members 10 fixed to the exterior body 5 with adhesive or the like are removed from the other components of the exterior body 5 using an appropriate solvent such as toluene, methyl ethyl ketone, or heptane, and the natural lengths of the elastic members 10 in the exterior body 5 are measured. From these measurements, the average length of all of the natural lengths of the elastic members 10 in the exterior body 5 is calculated. Then, in the outer casing 5, the ratio of the average length of the elastic members 10 in the expanded and stretched state to the average length of the elastic members 10 in their natural lengths is calculated, and this is taken as the average elongation rate of the elastic members 10 in the outer casing 5.

[0061] The average elongation rate of the plurality of elastic members 10 is preferably 150% or more, more preferably 200% or more, and is preferably 500% or less, more preferably 400% or less.

[0062] [Example of outer sheet configuration] The multiple thermoplastic sheets 50 include an outer layer sheet 51 that forms the non-skin side of the exterior body 5, and an inner layer sheet 52 adjacent to the outer layer sheet 51. The outer layer sheet 51 and the inner layer sheet 52 that form the multiple thermoplastic sheets 50 are preferably made of spunbond nonwoven fabric from the viewpoint of improving ease of tearing when discarding. From the viewpoint of sheet formability, the spunbond nonwoven fabric preferably contains a polyolefin such as polyethylene or polypropylene from among the above-mentioned thermoplastic resins, and more preferably contains polypropylene. Examples of polypropylene include α-olefins.

[0063] From the viewpoint of reliably fusing the fibers together to form a sheet, the spunbond nonwoven fabric used for the outer layer sheet 51 preferably has a low-density portion and a plurality of high-density portions spaced apart from one another within the low-density portion. The plurality of high-density portions are, for example, a plurality of embossed portions formed by compressing and fusing the fibers. Examples of embossed portions include those formed intermittently by thermocompression bonding using an embossing roll and a flat roll, those formed by ultrasonic fusing, and those formed by intermittently applying hot air to partially fuse the fibers. From the viewpoints of high productivity and low equipment costs, the embossed portions are preferably formed by thermocompression bonding. The planar shape of the embossed portion may be any shape such as a circle, an ellipse, a polygon, or shapes similar to these. The embossed portions are preferably formed in a regular pattern, but may also be formed in a random pattern. For example, the embossed portions are arranged at approximately regular intervals (pitch) in the vertical direction X and the horizontal direction Y, and each row in the horizontal direction Y is shifted by half a pitch from the adjacent rows. The plurality of high density portions may be constituted by filmed areas around the pin holes instead of the embossed portions.

[0064] FIG. 7 shows an example of a pattern of a plurality of high density portions (embossed portions) arranged at intervals within the low density portion of the outer layer sheet 51 and the inner layer sheet 52.

[0065] One of the outer layer sheet 51 and the inner layer sheet 52 is referred to as the first sheet 310, and the other is referred to as the second sheet 320. Either the outer layer sheet 51 or the inner layer sheet 52 may be the first sheet 310, or either may be the second sheet 320.

[0066] The first sheet 310 has a plurality of high-density portions 311 arranged at intervals within the low-density portion 312. The second sheet 320 has a plurality of high-density portions 321 arranged at intervals within the low-density portion 322. The pitch P1 in the longitudinal direction X of the plurality of high-density portions 311, 321 of at least one of the first sheet 310 or the second sheet 320 is preferably shorter than the pitch P2 (see FIG. 4 ) in the longitudinal direction X of the plurality of elastic members 10 of the second contractile portion 202 (which has a relatively low average contractile force per unit width). The pitch P1 in the longitudinal direction X of the plurality of high-density portions 311, 321 refers to the distance between the center of gravity of one high-density portion 311, 321 and the center of gravity of another high-density portion 311, 321 located closest in the longitudinal direction X. The pitch P2 in the longitudinal direction X of the plurality of elastic members 10 means the distance in the longitudinal direction X between two elastic members 10 that are closest in the longitudinal direction X. The pitch in the longitudinal direction X of the high density portions 311, 321 is shorter than the pitch in the longitudinal direction X of the plurality of elastic members 10 in the second contractile portion 202 (which has a relatively low average contractile force per unit width), so the high density portions 311, 321 are disposed between the plurality of elastic members 10 in the second contractile portion 202. As a result, the presence of high density portions with high material strength in the second contractile portion 202 increases the tear strength of the second contractile portion 202, making it possible to prevent lateral tearing of the second contractile portion 202.

[0067] It is preferable that the pitch P3 in the longitudinal direction X of the multiple high-density portions 311 of the first sheet 310 is different from the pitch P4 in the longitudinal direction X of the multiple high-density portions 321 of the second sheet 320. As a result, in the laminated sheet 330 in which the first sheet 310 and the second sheet 320 are laminated, the high-density portions 311, 321 are present so as to cover most of the longitudinal direction X, and therefore the material strength of most of the longitudinal direction X of the exterior body 5 is increased and it is less susceptible to lateral tearing.

[0068] It is preferable that the area ratio of the plurality of high-density portions 311 in the first sheet 310 differs from the area ratio of the plurality of high-density portions 321 in the second sheet 320. As a result, in a laminated sheet 330 in which the first sheet 310 and the second sheet 320 are laminated together, the positions of the plurality of high-density portions 311, 321 are misaligned in a planar direction consisting of the longitudinal direction X and the transverse direction Y. As a result, the high-density portions 311, 321 are present so as to cover most of the planar direction consisting of the longitudinal direction X and the transverse direction Y, and therefore the material strength of most of the longitudinal direction X of the exterior body 5 is increased, making it less susceptible to transverse tearing.

[0069] As shown in FIG. 8 , the pattern of the multiple high-density portions 311 in the first sheet 310 is preferably different from the pattern of the multiple high-density portions 321 in the second sheet 320. The patterns of the high-density portions 311 and 321 refer to the different shapes and sizes of the patterns formed by the lines connecting the centers of gravity of the high-density portions 311 and 321. Because the patterns of the high-density portions 311 and 321 are different, the positions of the multiple high-density portions 311 and 321 in the laminated sheet 330 formed by stacking the first sheet 310 and the second sheet 320 are less likely to overlap in the planar direction (the longitudinal direction X and the lateral direction Y). This allows the high-density portions 311 and 321 to cover most of the planar direction (the longitudinal direction X and the lateral direction Y), thereby increasing the material strength of the exterior package 5 and making it less susceptible to lateral tearing. Note that FIG. 8 also shows an example of another sheet 340 having high-density portions 341 and low-density portions 342 in addition to the first sheet 310 and the second sheet 320 having different patterns.

[0070] 9, it is preferable that the fiber orientation degree of the first sheet 310 is different from the fiber orientation degree of the second sheet 320. The different fiber orientation degrees result in different susceptibility to lateral tearing between the first sheet 310 and the second sheet 320. As a result, in a laminated sheet 330 in which the first sheet 310 and the second sheet 320 are laminated, the first sheet 310 and the second sheet 320 are less likely to lateral tear.

[0071] [Examples of thermoplastic sheet materials]

[0072] The multiple thermoplastic sheets 50 that make up the exterior body 5 may be made of sheets that contain cellulosic fibers in addition to thermoplastic fibers.

[0073] Here, in the pants-type diaper 1, the side joining portions 8 preferably have a structure that can prevent peeling when worn and while worn, and can be easily torn when discarded. From the viewpoint of achieving both tear resistance at the side joints 8 during wear and ease of tearing when doffing after use, it is preferable that the plurality of thermoplastic sheets 50 contain cellulosic fibers in addition to thermoplastic fibers. When the plurality of thermoplastic sheets 50 contain cellulosic fibers, when body fluids such as sweat are absorbed at the side joints 8 while the diaper 1 is being worn, the absorption of body fluids changes the bond strength between the ventral portion 5a and the dorsal portion 5b at the side joints 8. More specifically, the bond strength between the ventral portion 5a and the dorsal portion 5b at the side joints 8 after absorbing body fluids becomes lower than before absorption due to the inclusion of cellulosic fibers. As a result, the side joints 8 can be easily torn when removing the diaper from the wearer after use.

[0074] Examples of cellulosic fibers include natural cellulosic fibers such as cotton and pulp, and regenerated cellulosic fibers such as rayon and cupra. These fibers can be used alone or in combination of two or more. The cellulosic fibers may be short or long fibers. From the viewpoint of ease of tearing the side joints 8 when doffing the garment after use, natural cellulosic fibers are preferred as single fibers. In particular, using cotton as the cellulosic fibers can prevent the side joints 8 from tearing easily in the lateral direction Y, thereby preventing unexpected tearing. Furthermore, using pulp as the cellulosic fibers can allow the side joints 8 to tear with a uniform force when doffing the garment after use.

[0075] Furthermore, by using a sheet containing cellulose fibers such as cotton as the sheet constituting the waist area where sweat tends to accumulate, sweat from the wearer can be absorbed, providing a dry and comfortable fit.

[0076] [Modification of the configuration of the exterior body 5] Below, various modifications of the configuration of the exterior body 5 will be described.

[0077] [Variation 1] In the above embodiment, the reinforcing sheet is configured by a folded portion 100 formed by folding back an end 103 in the longitudinal direction X of the exterior body 5 from the waist opening end Wa in the longitudinal direction X. In contrast, the reinforcing sheet 300 in the first modification is a sheet independent of the exterior body 5.

[0078] FIG. 10 shows an example of the configuration of an exterior body according to the first modification.

[0079] The reinforcing sheet 300 faces the inner layer sheet 52 of the exterior body 5. The reinforcing sheet 300 is arranged in at least the second contracted portion 202 in the longitudinal direction X of the pair of side joints 8. Preferably, the folded-back portion 100 is arranged in the longitudinal direction X of the pair of side joints 8, spanning at least both ends 202a, 202b of the second contracted portion 202 in the longitudinal direction X. Preferably, the reinforcing sheet 300 is arranged so as to straddle both ends 202a, 202b of the second contracted portion 202 in the longitudinal direction X. Preferably, the reinforcing sheet 300 is arranged so as to continuously cover at least the first contracted portion 201 and the second contracted portion 202 in the longitudinal direction X of the pair of side joints 8.

[0080] In this example, the reinforcing sheet 300 is arranged in the longitudinal direction X of the pair of side joints 8 so as to cover the first contraction portion 201 and the second contraction portion 202, and to cover the area 203a of the third contraction portion 203 adjacent to the second contraction portion 202.

[0081] The reinforcing sheet 300 is arranged in the lateral direction Y across the pair of side joint portions 8 to cover at least the second contracted portion 202. In this example, the reinforcing sheet 300 is arranged in the lateral direction Y across the pair of side joint portions 8 to cover the first contracted portion 201 and the second contracted portion 202, and to cover the region 203a of the third contracted portion 203 adjacent to the second contracted portion 202. The reinforcing sheet 300 is joined by the pair of side joint portions 8 together with the side edge portion 5d in the lateral direction Y of the ventral portion 5a and the side edge portion 5e in the lateral direction Y of the dorsal portion 5b.

[0082] In this way, both ends of the reinforcing sheet 300 in the horizontal direction Y are joined to the exterior body 5 by a pair of side joints 8, but one end in the vertical direction X is not continuous with the end 103 of the exterior body 5. In other words, the position of the reinforcing sheet 300 relative to the exterior body 5 is fixed by only two sides of the pair of side joints 8. For this reason, in order to fix the position of the reinforcing sheet 300 relative to the exterior body 5, it is preferable to join the reinforcing sheet 300 planarly to the inner layer sheet 52 of the exterior body 5 using the reinforcing sheet joint 101. The configuration of the reinforcing sheet joint 101 is the same as in the above embodiment.

[0083] Modification 1 also has the same effect as the above embodiment. As yet another modification, the reinforcing sheet 300, which is independent of the exterior body 5, does not have to be arranged so as to cover at least the second contracted portion 202 in the lateral direction Y across a pair of side joints 8. Specifically, two pieces of reinforcing sheet 300 of a minimum size that can be joined at the side joints 8 may be prepared, and the two pieces of reinforcing sheet 300 may be joined by each of the pair of side joints 8. In short, the two pieces of reinforcing sheet 300 may be arranged at least in the second contracted portion 202 in the longitudinal direction X of the pair of side joints 8, and may be joined by the pair of side joints 8 together with the side edge 5d in the lateral direction Y of the ventral portion 5a and the side edge 5e in the lateral direction Y of the dorsal portion 5b.

[0084] [Variation 2] In the above embodiment, at least one of the ventral portion 5a and the dorsal portion 5b of the exterior body 5 includes the fourth contracting portion 204, the first contracting portion 201, the second contracting portion 202, and the third contracting portion 203. In contrast, in Modification 2, both the ventral portion 5a and the dorsal portion 5b of the exterior body 5 include the fourth contracting portion 204, the first contracting portion 201, the second contracting portion 202, and the third contracting portion 203, respectively.

[0085] FIG. 11 shows an example of the configuration of an exterior body according to the second modification.

[0086] In the second modification, the positions of the absorbent main body ventral end 4A and the absorbent main body dorsal end 4B in the longitudinal direction X are different. Specifically, the absorbent main body dorsal end 4B is located closer to (upper than) the waist opening end Wa of the waist opening 1W than the absorbent main body ventral end 4A. Both the ventral side portion 5a and the dorsal side portion 5b of the outer cover 5 include, in order from the waist opening 1W toward the leg openings 1L, a fourth contracted portion 204 (having a relatively low average contractile force per unit width), a first contracted portion 201 (having a relatively high average contractile force per unit width), a second contracted portion 202 (having a relatively low average contractile force per unit width), and a third contracted portion 203 (having a relatively high average contractile force per unit width). The second contracted portion 202 of the ventral side portion 5a and the second contracted portion 202 of the dorsal side portion 5b are arranged in positions that do not overlap in the longitudinal direction X.

[0087] As described above, when the diaper 1 is disposed of by tearing the side joint portion 8 of the outer casing 5 in the vertical direction X from the waist end portion 8a toward the leg end portion 8b, when the first contraction portion 201 (which has a relatively high average contraction force per unit width) has finished tearing and the second contraction portion 202 (which has a relatively low average contraction force per unit width) begins to tear, the first contraction portion 201 may shrink significantly, and the force tearing the side joint portion 8 in the vertical direction X may act in the horizontal direction Y, causing the second contraction portion 202 to tear laterally in the horizontal direction Y.

[0088] Therefore, in this modification, the end in the horizontal direction Y of the second contracting portion 202 of the ventral portion 5a and the end in the horizontal direction Y of the first contracting portion 201 or the third contracting portion 203 of the dorsal portion 5b are arranged at positions where they overlap in the vertical direction X. The end in the horizontal direction Y of the second contracting portion 202 of the dorsal portion 5b and the end in the horizontal direction Y of the first contracting portion 201 or the third contracting portion 203 of the ventral portion 5a are arranged at positions where they overlap in the vertical direction X. In the illustrated example, the end in the horizontal direction Y of the second contracting portion 202 of the ventral portion 5a and the end in the horizontal direction Y of the first contracting portion 201 of the dorsal portion 5b are arranged at positions where they overlap in the vertical direction X. The end in the horizontal direction Y of the second contracting portion 202 of the dorsal portion 5b and the end in the horizontal direction Y of the third contracting portion 203 of the ventral portion 5a are arranged at positions where they overlap in the vertical direction X.

[0089] As a result, when the side joint portion 8 of the outer body 5 is torn in the vertical direction X from the waist end portion 8a toward the leg end portion 8b, even if the first contraction portion 201 of the ventral portion 5a has contracted significantly when the first contraction portion 201 (which has a relatively high average contraction force per unit width) has finished tearing and the second contraction portion 202 of the ventral portion 5a (which has a relatively low average contraction force per unit width) begins to tear, the second contraction portion 202 of the ventral portion 5a is less likely to tear horizontally in the horizontal direction Y because the second contraction portion 202 of the ventral portion 5a is reinforced by the first contraction portion 201 of the dorsal portion 5b. Thereafter, when the first contraction portion 201 of the dorsal portion 5b (which has a relatively high average contraction force per unit width) has finished tearing and the second contraction portion 202 of the dorsal portion 5b (which has a relatively low average contraction force per unit width) begins to tear, even if the first contraction portion 201 of the dorsal portion 5b has shrunk significantly, the second contraction portion 202 of the dorsal portion 5b is not likely to tear horizontally in the lateral direction Y because it is reinforced by the third contraction portion 203 of the ventral portion 5a.

[0090] In the second modification, the configuration of the exterior body 5 may be the same as that of the above embodiment or each modification.

[0091] [Variation 3] FIG. 12 shows an example of the configuration of an exterior body according to the third modification.

[0092] At least one of the ventral portion 5a and the dorsal portion 5b of the exterior body 5 of the third modification has a folded portion 100 (reinforcing sheet) and a reinforcing sheet joint portion 101 similar to those of the above embodiment.

[0093] The reinforcing sheet joint portion 101 is disposed inside the second contraction portion 202 in the longitudinal direction X. In other words, the reinforcing sheet joint portion 101 is disposed in the longitudinal direction X across both ends 202a, 202b of the second contraction portion 202 in the longitudinal direction X.

[0094] At least one of the ventral portion 5a and the rear portion 5b of the exterior body 5 has a bond strength reducing portion 400 arranged between the multiple thermoplastic sheets 50. The bond strength reducing portion 400 includes a bond strength reducing agent applied to the inside of the third contracted portion 203 in the longitudinal direction X. The bond strength reducing portion 400 may also be arranged in the pair of side joint portions 8 in the transverse direction Y. The bond strength reducing agent is made of a hot melt adhesive, similar to the reinforcing sheet joint portion 101. As the hot melt adhesive, for example, a styrene-based (SIS, SBS, SEBS) or polyolefin-based material can be used.

[0095] The folded-back portion 100 (reinforcing sheet) is arranged so as to straddle the boundary 202b between the second contracted portion 202 and the third contracted portion 203 in the longitudinal direction X and cover at least a part of the third contracted portion 203. An end 102 of the folded-back portion 100 on the leg opening 1L side in the longitudinal direction X is located inside the third contracted portion 203 in the longitudinal direction X.

[0096] The bonding strength reduced portion 400 is disposed in a region in the longitudinal direction X where the folded portion 100 covers at least a part of the third contracted portion 203. In other words, one end of the bonding strength reduced portion 400 in the longitudinal direction X is disposed at the boundary 202b between the second contracted portion 202 and the third contracted portion 203. Meanwhile, the other end of the bonding strength reduced portion 400 in the longitudinal direction X is disposed at a position overlapping, in the longitudinal direction X, with the end 102 of the folded portion 100 on the leg opening 1L side in the longitudinal direction X. In short, the bonding strength reduced portion 400 is disposed so as to straddle the end 102 of the folded portion 100, which is the boundary between a portion where the folded portion 100 is present and a portion where the folded portion 100 is not present (i.e., the boundary where the number of laminated layers changes). The bonding strength reduced portion 400 may be arranged so as to straddle the boundary where the number of laminated sheets changes, and as shown in the figure, may be arranged so that the bonding strength reduced portion 400 and the reinforcing sheet joint portion 101 do not overlap in the vertical direction X. Not overlapping in the vertical direction X means that, as shown in Figure 12, one end of the bonding strength reduced portion 400 and one end of the reinforcing sheet joint portion 101 coincide (are flush) in the vertical direction X, or there is a gap (not shown) between one end of the bonding strength reduced portion 400 and one end of the reinforcing sheet joint portion 101 in the vertical direction X.

[0097] A portion of the side joint portion 8 has, in order in the longitudinal direction X from the waist opening 1W toward the leg openings 1L, a first region 501, a second region 502, and a third region 503. The first region 501 includes a second contraction portion 202 (having a relatively low average contraction force per unit width), a folded-back portion 100, three stacked sheets (the outer layer sheet 51, the inner layer sheet 52, and the folded-back portion 100), a reinforcing sheet joint portion 101, and no joint strength reduced portion 400. The second region 502 includes the second contraction portion 202 (having a relatively low average contraction force per unit width) and a third contraction portion 203 (having a relatively high average contraction force per unit width), a folded-back portion 100, three stacked sheets (the outer layer sheet 51, the inner layer sheet 52, and the folded-back portion 100), no reinforcing sheet joint portion 101, and a joint strength reduced portion 400. The third region 503 includes a third contraction portion 203 (having a relatively high average contraction force per unit width), does not have a folded portion 100, has two laminated sheets (outer layer sheet 51, inner layer sheet 52), does not have a reinforcing sheet joint portion 101, and has a reduced joint strength portion 400.

[0098] If the influence of the reduced bonding strength portion 400 is not taken into consideration, the first region 501 includes the reinforcing sheet bonding portion 101, and therefore has a relatively higher strength than the second region 502, which does not include the reinforcing sheet bonding portion 101, despite having the same number of stacked layers (3 layers). In addition, the second region 502 has a large number of laminated sheets (three sheets), and therefore has a relatively high strength compared to the third region 503 (two sheets).

[0099] Therefore, if the influence of the reduced bond strength portion 400 is not taken into consideration, when the side bond portion 8 of the outer casing 5 is torn in the longitudinal direction X during disposal of the diaper 1, once the first contracted portion 201 has finished tearing and the second contracted portion 202 has begun to tear, the first contracted portion 201 will shrink significantly, making it easier for the tearing force to act in the lateral direction Y. Within the second contracted portion 202, once the first region 501 (three layers, with reinforcing sheet joint 101) has finished tearing and the second region 502 (three layers, without reinforcing sheet joint 101) has begun to tear, the reinforcing sheet joint 101 has a high seal strength and is difficult to tear, so there is a risk of horizontal tearing in the lateral direction Y.

[0100] Therefore, in this modification, a bond strength reduced portion 400 is provided across at least the second region 502 (i.e., including the region where the folded-back portion 100 covers at least a portion of the third contracted portion 203 in the vertical direction X). This reduces the difference in seal strength between the first region 501 and the second region 502. This prevents the first region 501 from contracting significantly when tearing the first region 501 and starting to tear the second region 502, and prevents the second region 502 from tearing laterally in the horizontal direction Y.

[0101] [Variation 4] FIG. 13 shows an example of the configuration of an exterior body according to the fourth modification.

[0102] At least one of the ventral portion 5a or the dorsal portion 5b of the exterior body 5 of Variation 4 has a folded portion 100 (reinforcing sheet) and a bonding strength reducer similar to those of Variation 3. However, Variation 3 and Variation 4 differ in the region where the reinforcing sheet bonding portion 101 is arranged.

[0103] 12 , in Modification 3, the joint strength reduced portion 400 and the reinforcing sheet joint portion 101 are arranged so as not to overlap in the vertical direction X. In contrast, in Modification 4, the reinforcing sheet joint portion 101 is arranged on the exterior body 5 so as to straddle the boundary 202b between the second contraction portion 202 and the third contraction portion 203.

[0104] For this reason, in Modification 4, the second region 502 has a waist-side region 502c and a leg-side region 502d. The reinforcing sheet joint portion 101 and the bond strength reduced portion 400 are arranged in the waist-side region 502c. In other words, the coated regions of the reinforcing sheet joint portion 101 and the bond strength reduced portion 400 overlap in the waist-side region 502c. The leg-side region 502d does not have the reinforcing sheet joint portion 101, but has the bond strength reduced portion 400. As a result, the strength of the leg-side region 502d is the same as that of the second region 502 in Modification 3, but the strength of the waist-side region 502c is lower than the strength of the leg-side region 502d.

[0105] This reduces the difference in strength between the first region 501 and the waist side region 502c of the second region 502. This prevents the first region 501 from shrinking too much when tearing the first region 501 and starting to tear the waist side region 502c of the second region 502, preventing the waist side region 502c of the second region 502 from tearing horizontally in the horizontal direction Y and facilitating continuous tearing in the vertical direction X.

[0106] [Variation 5] In the above embodiment and each modified example, the folded portion 100 (reinforcing sheet) or the reinforcing sheet 300 faces the inner layer sheet 52 of the exterior body 5 and is arranged on the skin side of the exterior body 5. In contrast, the folded portion 100 (reinforcing sheet) or the reinforcing sheet 300 may face the outer layer sheet 51 of the exterior body 5 and be arranged on the non-skin side of the exterior body 5 (not shown). Alternatively, the folded portion 100 (reinforcing sheet) or the reinforcing sheet 300 may be arranged so as to be sandwiched between the outer layer sheet 51 and the inner layer sheet 52 (not shown).

[0107] [Reinforcing sheet joints and areas with reduced joint strength] The following describes the reinforcing sheet joint parts 101 and the joint strength reduced parts 400 of Modifications 3 and 4. In particular, it is assumed that the reinforcing sheet joint parts 101 and the joint strength reduced parts 400 are made of the same type of hot melt adhesive.

[0108] [Basic weight] The basis weight of the bonding strength reducing agent contained in the bonding strength reducing portion 400 of the exterior package 5 is higher than the basis weight of the adhesive applied to the reinforcing sheet at the reinforcing sheet joint portion 101 of the folded-back portion 100 (reinforcing sheet). The higher the basis weight of the bonding strength reducing agent contained in the bonding strength reducing portion 400, the weaker the strength. In this way, the bonding strength reducing portion 400 containing the bonding strength reducing agent with a high basis weight is provided at least in the second region 502 (i.e., the region where the folded-back portion 100 covers at least a portion of the third contracted portion 203 in the longitudinal direction X) across the longitudinal direction X. This further weakens the strength of the second region 502, which has a relatively high strength. This further reduces the difference in strength between the second region 502 and the third region 503. As a result, when the first contracted portion 201 has been torn and the second contracted portion 202 begins to tear, the first contracted portion 201 contracts significantly, making it easier for a force to act in the lateral direction Y. Furthermore, as the tear length increases (i.e., as the tear length approaches the boundary 202b between the second contraction portion 202 and the third contraction portion 203), force is more likely to be applied in the lateral direction Y, and the seal strength can be further reduced, thereby preventing lateral tearing.

[0109] [Method of measuring basis weight] The area coated with the reduced bonding strength portion 400 and the area coated with the reinforcing sheet bonding portion 101 are cut out from the exterior body 5. Each area is dissolved with a solvent. The weight of each area is calculated by subtracting the weight after dissolution from the weight before dissolution. This weight difference is the amount of adhesive applied. The basis weight is calculated by dividing the amount of adhesive applied by the coated area.

[0110] [pattern] FIG. 14 shows examples of coating patterns for the reinforcing sheet joints and joint strength reduced areas.

[0111] The reinforcing sheet joining portion 101 includes an adhesive applied to the folded portion 100 (reinforcing sheet) and has a coated portion 101A coated with the adhesive and an uncoated portion 101B not coated with the adhesive. The bonding strength reduced portion 400 has a coated portion 400A coated with a bonding strength reducer and an uncoated portion 400B not coated with the bonding strength reducer.

[0112] The coating area ratio of the coating area 400A of the bonding strength reducing agent in the bonding strength reducing portion 400 is higher than the coating area ratio of the coating area 101A of the adhesive in the reinforcing sheet bonding portion 101. The higher the coating area ratio of the coating area 400A of the bonding strength reducing agent in the bonding strength reducing portion 400, the weaker the strength. In this way, the bonding strength reducing portion 400 with a high coating area ratio is provided across at least the second region 502 (i.e., the region where the folded-back portion 100 covers at least a part of the third contracted portion 203 in the longitudinal direction X).

[0113] Furthermore, if the coating area ratio of the bonding strength reducing agent in the bonding strength reduced portion 400 is high, the bonding strength reduced portion 400 is likely to overlap the side seal portions S of the pair of side bonding portions 8. This weakens the bonding strength of the side seal portions S.

[0114] This further weakens the strength of the second region 502, which has a relatively high strength. This further reduces the difference in strength between the second region 502 and the third region 503. As a result, when the first contracted portion 201 has been torn and the second contracted portion 202 begins to be torn, the first contracted portion 201 contracts significantly, making it easier for a force to act in the lateral direction Y. Furthermore, the longer the tear length (i.e., the closer it gets to the boundary 202b between the second contracted portion 202 and the third contracted portion 203), the easier it is for a force to act in the lateral direction Y, and therefore the seal strength can be further reduced, thereby preventing lateral tearing.

[0115] The coated portion 101A of the reinforcing sheet joint portion 101 may have a pattern such as linear (A), wavy (B), or spiral (C). The coated portion 400A of the bond strength reduced portion 400 may have a pattern such as linear (D), wavy (E), or spiral (F). As long as the coating area ratio of the coated portion 400A of the bond strength reduced portion 400 with the bonding strength reducing agent is higher than the coating area ratio of the coated portion 101A of the reinforcing sheet joint portion 101 with the adhesive, the pattern of the coated portion 101A of the reinforcing sheet joint portion 101 and the pattern of the coated portion 400A of the bond strength reduced portion 400 may be the same or different. For example, the patterns may be the same, such as the coated portion 101A of the reinforcing sheet joint portion 101 having a wavy (B) pattern and the coated portion 400A of the bond strength reduced portion 400 having a wavy (E) pattern. Alternatively, the patterns may be different, such as the coated portion 101A of the reinforcing sheet joint portion 101 having a wave pattern (B) and the coated portion 400A of the joint strength reduced portion 400 having a spiral pattern (F).

[0116] [Method for measuring coating area ratio] The outer layer sheet 51 or inner layer sheet 52 coated with the bond strength reduction portion 400 and the folded portion 100 coated with the reinforcing sheet bond portion 101 are peeled off from the exterior body 5, and the contraction of the elastic member 10 is stretched to bring it into an elongated state. A toner that reacts with the bonding agent is sprinkled on the bonded surfaces. The coated and uncoated portions are binarized based on the amount of color or fluorescence of the toner, and the coated area ratio is calculated.

[0117] Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and it goes without saying that various modifications can be made within the scope of the gist of the present invention.

[0118] For example, in the above embodiment, the exterior body 5 has been described as having a ventral portion 5a, a dorsal portion 5b, and a crotch portion 5c, but is not limited thereto. For example, the exterior body 5 may have a configuration in which the ventral portion and the dorsal portion are separated without having a crotch portion.

[0119] The pants-type absorbent article according to the present invention does not have to be a disposable diaper for infants, but may be, for example, a disposable diaper for adults or children. Furthermore, the pants-type absorbent article according to the present invention does not have to be a disposable diaper as long as it is an absorbent article worn on the lower body. Examples of such pants-type absorbent articles include pants-type sanitary napkins.

[0120] In relation to the above-described embodiments, the present invention further discloses the following absorbent article. <1> A pants-type absorbent article comprising an absorbent main body, and an outer body including a plurality of thermoplastic sheets and disposed on the non-skin side of the absorbent main body, the outer body having a waist opening and a pair of leg openings, the article having a vertical direction extending from the wearer's abdomen side through the crotch region to the back side, and a horizontal direction perpendicular to the vertical direction, The exterior body is a ventral portion disposed on the ventral side of the wearer; a back portion disposed on the back of the wearer; a pair of side joint portions at which side edges in the lateral direction of the ventral portion and side edges in the lateral direction of the dorsal portion are joined, At least one of the ventral side portion and the dorsal side portion of the exterior body is a first contraction portion in which a plurality of elastic members extending in the transverse direction are arranged; a second contracted portion in which a plurality of elastic members extending in the horizontal direction are arranged, the second contracted portion is continuous with the first contracted portion in the vertical direction, and is located closer to the leg opening in the vertical direction than the first contracted portion, a first contraction force, which is an average contraction force per unit width in the lateral direction of the first contraction portion, is higher than a second contraction force, which is an average contraction force per unit width in the lateral direction of the second contraction portion; a reinforcing sheet disposed at least in the second contracted portion in the longitudinal direction of the pair of side joints and joined together with the side edge portions of the abdominal side portion and the side edge portions of the dorsal side portion by the pair of side joints; Pants-type absorbent article. <2> The difference between the first average contractile force and the second average contractile force is more than 0 cN / mm, preferably 0.2 to 6.0 cN / mm, and particularly preferably 0.2 to 3.0 cN / mm. <1> The pants-type absorbent article according to claim 1. <3> The first average contractile force is 2.0 to 9.0 cN / mm, particularly 2.0 to 7.0 cN / mm. <1> or <2> The pants-type absorbent article according to claim 1. <4> The second average contractile force is 0.4 to 6.0 cN / mm, particularly 0.4 to 3.5 cN / mm. <1> ~ <3> 10. The pants-type absorbent article according to any one of the above. <5> The reinforcing sheet is The second contraction portion is disposed across the pair of side joint portions in the lateral direction, and the reinforcing sheet has a reinforcing sheet joining portion where the reinforcing sheet is joined to the exterior body, The reinforcing sheet joint portion is disposed inside the second contracted portion in the longitudinal direction. The aforementioned <1> ~ <5> The pants-type absorbent article according to claim 1. <6> The reinforcing sheet joint is arranged to include a component in the longitudinal direction. The aforementioned <5> The pants-type absorbent article according to claim 1. <7> the reinforcing sheet is disposed so as to straddle both ends of the second contractible portion in the longitudinal direction, The reinforcing sheet joint portion is disposed on the exterior body so as to straddle both ends of the second contraction portion in the longitudinal direction. The aforementioned <5> or <6> The pants-type absorbent article according to claim 1. <8> The reinforcing sheet joint portion includes an adhesive applied to the reinforcing sheet. 8. The pants-type absorbent article according to claim 5. <9> The reinforcing sheet is disposed so as to continuously cover at least the first contracted portion and the second contracted portion in the longitudinal direction of the pair of side joint portions. The aforementioned <1> ~ <8> 10. The pants-type absorbent article according to any one of the above. <10> At least one of the ventral side portion and the dorsal side portion of the exterior body is the end portion of the exterior body in the vertical direction has a folded portion folded back in the vertical direction from the waist opening, The reinforcing sheet is constituted by the folded portion. <9> The pants-type absorbent article according to claim 1. <11> The reinforcing sheet is The second contraction portion is disposed across the pair of side joint portions in the lateral direction, and the reinforcing sheet has a reinforcing sheet joining portion where the reinforcing sheet is joined to the exterior body, The reinforcing sheet joint portion is disposed so as to continuously cover at least the first contracted portion and the second contracted portion in the longitudinal direction of the folded-back portion. The aforementioned <10> The pants-type absorbent article according to claim 1. <12> the ventral portion of the exterior body includes the first contraction portion and the second contraction portion, the rear side portion of the exterior body includes the first contracted portion and the second contracted portion, The second contracted portion of the ventral side portion and the second contracted portion of the dorsal side portion are disposed at positions where they do not overlap in the longitudinal direction. The aforementioned <1> ~ <11> 10. The pants-type absorbent article according to any one of the above. <13> At least one of the ventral side portion and the dorsal side portion of the exterior body is a third contracted portion, in which a plurality of elastic members extending in the horizontal direction are arranged, which is continuous with the second contracted portion in the vertical direction and is located closer to the leg opening in the vertical direction than the second contracted portion; a third contraction force, which is an average contraction force per unit width in the lateral direction of the third contraction portion, is higher than the second contraction force of the second contraction portion; The reinforcing sheet is the second contracted portion and the third contracted portion are disposed across the boundary between the second contracted portion and the third contracted portion in the vertical direction so as to cover at least a portion of the third contracted portion; At least one of the ventral side portion and the dorsal side portion of the exterior body is The reinforcing sheet has a bonding strength reducing portion disposed between the plurality of thermoplastic sheets, the bonding strength reducing portion containing a bonding strength reducing agent applied to an area where the reinforcing sheet covers at least a part of the third contracted portion in the longitudinal direction. The aforementioned <1> ~ <12> 10. The pants-type absorbent article according to any one of the above. <14> The difference between the third average contractile force and the second average contractile force is more than 0 cN / mm, preferably 0.2 to 6.0 cN / mm, and particularly preferably 0.2 to 3.0 cN / mm. <13> The pants-type absorbent article according to claim 1. <15> the third average contractile force is 2.0 to 9.0 cN / mm, particularly 2.0 to 7.0 cN / mm; <13> or <14> The pants-type absorbent article according to claim 1. <16> the reinforcing sheet has a reinforcing sheet joint portion at which the reinforcing sheet is joined to the exterior body, The reinforcing sheet joint portion is disposed on the exterior body so as to straddle the boundary between the second contraction portion and the third contraction portion. The aforementioned <13> ~ <15> 10. The pants-type absorbent article according to any one of the above. <17> the reinforcing sheet joint portion includes an adhesive applied to the reinforcing sheet, The basis weight of the bonding strength reducing agent contained in the bonding strength reducing portion of the exterior body is higher than the basis weight of the adhesive contained in the reinforcing sheet bonding portion of the reinforcing sheet. The aforementioned <13> ~ <16> 10. The pants-type absorbent article according to any one of the above. <18> The reinforcing sheet joint portion is An adhesive is applied to the reinforcing sheet, The adhesive sheet has a coated portion coated with the adhesive and a non-coated portion not coated with the adhesive, the bonding strength reduced portion has a coated portion to which the bonding strength reducing agent is applied and a non-coated portion to which the bonding strength reducing agent is not applied, The coating area ratio of the bonding strength reducing agent in the bonding strength reduced portion is higher than the coating area ratio of the adhesive in the reinforcing sheet bonding portion. The aforementioned <13> ~ <17> 10. The pants-type absorbent article according to any one of the above. <19> At least one of the plurality of thermoplastic sheets is a low density portion; a plurality of high density portions spaced apart from one another within the low density portion; The pitch of the plurality of high-density portions in the longitudinal direction is shorter than the pitch of the plurality of elastic members in the second contraction portion in the longitudinal direction. The aforementioned <1> ~ <18> 10. The pants-type absorbent article according to any one of the above. <20> the plurality of thermoplastic sheets includes a first sheet and a second sheet; The first sheet is a low density portion; a plurality of high density portions spaced apart from one another within the low density portion; The second sheet is a low density portion; a plurality of high density portions spaced apart from one another within the low density portion; The pitch of the plurality of high-density portions of the first sheet in the longitudinal direction is different from the pitch of the plurality of high-density portions of the second sheet in the longitudinal direction. The aforementioned <1> ~ <19> 10. The pants-type absorbent article according to claim 1, <21> the plurality of thermoplastic sheets includes a first sheet and a second sheet; The first sheet is a low density portion; a plurality of high density portions spaced apart from one another within the low density portion; The second sheet is a low density portion; a plurality of high density portions spaced apart from one another within the low density portion; The area ratio of the plurality of high-density portions in the first sheet is different from the area ratio of the plurality of high-density portions in the second sheet. The aforementioned <1> ~ <20> 10. The pants-type absorbent article according to any one of the above. <22> the plurality of thermoplastic sheets includes a first sheet and a second sheet; The first sheet is a low density portion; a plurality of high density portions spaced apart from one another within the low density portion; The second sheet is a low density portion; a plurality of high density portions spaced apart from one another within the low density portion; The pattern of the plurality of high-density portions of the first sheet and the pattern of the plurality of high-density portions of the second sheet are different. The aforementioned <1> ~ <21> 10. The pants-type absorbent article according to any one of the above. <23> the plurality of thermoplastic sheets includes a first sheet and a second sheet; The fiber orientation degree of the first sheet and the fiber orientation degree of the second sheet are different. The aforementioned <1> ~ <22> 10. The pants-type absorbent article according to any one of the above. <24> a fourth contraction portion that is continuous with the first contraction portion in the longitudinal direction and is located closer to the waist opening than the first contraction portion in the longitudinal direction, A fourth contraction force, which is an average contraction force per unit width in the lateral direction of the fourth contraction portion, is lower than the first contraction force of the first contraction portion. The aforementioned <1> ~ <23> 10. The pants-type absorbent article according to any one of the above. <25> The difference between the first average contractile force and the fourth average contractile force is more than 0 cN / mm, preferably 0.2 to 6.0 cN / mm, and particularly preferably 0.4 to 3.0 cN / mm. <24> The pants-type absorbent article according to claim 1. <26> the fourth average contractile force is 0.2 to 9.0 cN / mm, particularly 0.2 to 4.0 cN / mm; <24> or <25> The pants-type absorbent article according to claim 1. [Explanation of symbols]

[0121] 1...Pants-type absorbent articles (disposable diapers, diapers) 4...Absorbent body 5...Exterior body 5a...ventral part 5b...dorsal part 50...Thermoplastic sheet 8...Side joint 8a...waist end 8b...Leg end S...Seal 100...Folded part 101...Reinforcement sheet joint 300...Reinforcement sheet 400…Joining strength decreased part 201...First contraction section 202...second contraction section 203...Third contraction 204...Fourth contraction

Claims

1. A pants-type absorbent article comprising an absorbent main body, and an outer body including a plurality of thermoplastic sheets and disposed on the non-skin side of the absorbent main body, the outer body having a waist opening and a pair of leg openings, the article having a vertical direction extending from the wearer's abdomen side through the crotch region to the back side, and a horizontal direction perpendicular to the vertical direction, The outer casing is a ventral portion disposed on the ventral side of the wearer; a back portion disposed on the back of the wearer; a pair of side joint portions at which side edges in the lateral direction of the ventral portion and side edges in the lateral direction of the dorsal portion are joined, At least one of the ventral side portion and the dorsal side portion of the exterior body is a first contraction portion in a region that contacts a portion of the wearer from the iliac crest to the anterior superior iliac spine, and in which a plurality of elastic members extending in the lateral direction are arranged; a second contraction portion, in which a plurality of elastic members extending in the horizontal direction are arranged, the second contraction portion being continuous with the first contraction portion in the vertical direction and being located closer to the leg opening portion in the vertical direction than the first contraction portion; a third contracted portion in which a plurality of elastic members extending in the horizontal direction are arranged, the third contracted portion is continuous with the second contracted portion in the vertical direction, and is located closer to the leg opening in the vertical direction than the second contracted portion, the first contracted portion, the second contracted portion, and the third contracted portion are defined by dividing a distance from one of both ends of the absorbent main body in the longitudinal direction to an end of the third contracted portion on the leg opening side into three equal parts, a first contraction force, which is an average contraction force per unit width in the lateral direction of the first contraction portion, is higher than a second contraction force, which is an average contraction force per unit width in the lateral direction of the second contraction portion; a third contraction force, which is an average contraction force per unit width in the lateral direction of the third contraction portion, is higher than the second contraction force of the second contraction portion; a reinforcing sheet disposed at least in the second contracted portion in the longitudinal direction of the pair of side joints, and joined together with the side edge portions of the abdominal side portion and the side edge portions of the dorsal side portion by the pair of side joints; Pants-type absorbent article.

2. The reinforcing sheet is the second contracted portion is disposed across the pair of side joint portions in the lateral direction, and the reinforcing sheet has a reinforcing sheet joining portion where the reinforcing sheet is joined to the exterior body, The reinforcing sheet joint portion is disposed inside the second contracted portion in the longitudinal direction. The pants-type absorbent article according to claim 1.

3. The reinforcing sheet joint is arranged to include a component in the longitudinal direction. The pants-type absorbent article according to claim 2.

4. the reinforcing sheet is disposed across both ends of the second contraction portion in the longitudinal direction, The reinforcing sheet joint portion is disposed on the exterior body so as to straddle both ends of the second contraction portion in the longitudinal direction. The pants-type absorbent article according to claim 2 or 3.

5. The reinforcing sheet joint portion includes an adhesive applied to the reinforcing sheet. The pants-type absorbent article according to any one of claims 2 to 4.

6. The reinforcing sheet is disposed so as to continuously cover at least the first contracted portion and the second contracted portion in the longitudinal direction of the pair of side joint portions. The pants-type absorbent article according to any one of claims 1 to 5.

7. At least one of the ventral side portion and the dorsal side portion of the exterior body is the end portion of the exterior body in the vertical direction has a folded portion folded back in the vertical direction from the waist opening, The reinforcing sheet is constituted by the folded portion. The pants-type absorbent article according to claim 6.

8. The reinforcing sheet is the second contracted portion is disposed across the pair of side joint portions in the lateral direction, and the reinforcing sheet has a reinforcing sheet joining portion where the reinforcing sheet is joined to the exterior body, The reinforcing sheet joint portion is disposed so as to continuously cover at least the first contracted portion and the second contracted portion in the longitudinal direction of the folded-back portion. The pants-type absorbent article according to claim 7.

9. the ventral portion of the exterior body includes the first contraction portion and the second contraction portion, the rear side portion of the exterior body includes the first contracted portion and the second contracted portion, The second contracted portion of the ventral side portion and the second contracted portion of the dorsal side portion are arranged at positions where they do not overlap in the vertical direction. The pants-type absorbent article according to any one of claims 1 to 8.

10. The reinforcing sheet is arranged so as to straddle the boundary between the second contraction portion and the third contraction portion in the vertical direction and cover at least a portion of the third contraction portion. The pants-type absorbent article according to any one of claims 1 to 9.

11. the reinforcing sheet has a reinforcing sheet joint portion at which the reinforcing sheet is joined to the exterior body, The reinforcing sheet joint portion is disposed on the exterior body so as to straddle the boundary between the second contraction portion and the third contraction portion. The pants-type absorbent article according to any one of claims 1 to 10.

12. The outer body has, as the plurality of thermoplastic sheets, an inner layer sheet and an outer layer sheet arranged on the non-skin side of the inner layer sheet, The reinforcing sheet is a folded portion made of the outer layer sheet arranged so as to straddle the second contraction portion, and has a reinforcing sheet joint portion where the reinforcing sheet is joined to the exterior body, the reinforcing sheet joint portion is made of an adhesive, and the adhesive is applied to the folded portion. The pants-type absorbent article according to any one of claims 1 to 11.

13. At least one of the ventral portion or the dorsal portion of the outer casing further includes a fourth contraction portion that is continuous with the first contraction portion in the vertical direction and is located closer to the waist opening side than the first contraction portion in the vertical direction; A fourth contraction force, which is an average contraction force per unit width in the lateral direction of the fourth contraction portion, is lower than the first contraction force of the first contraction portion. The pants-type absorbent article according to any one of claims 1 to 12.

14. At least one of the plurality of thermoplastic sheets is a low density portion; a plurality of high density portions spaced apart from one another within the low density portion; The pitch of the plurality of high-density portions in the longitudinal direction is shorter than the pitch of the plurality of elastic members in the second contraction portion in the longitudinal direction. The pants-type absorbent article according to any one of claims 1 to 13.

15. the plurality of thermoplastic sheets includes a first sheet and a second sheet; The first sheet comprises: a low density portion; a plurality of high density portions spaced apart from one another within the low density portion; The second sheet comprises: a low density portion; a plurality of high density portions spaced apart from one another within the low density portion; The pitch of the high density portions of the first sheet in the longitudinal direction is different from the pitch of the high density portions of the second sheet in the longitudinal direction. The pants-type absorbent article according to any one of claims 1 to 14.

16. the plurality of thermoplastic sheets includes a first sheet and a second sheet; The first sheet comprises: a low density portion; a plurality of high density portions spaced apart from one another within the low density portion; The second sheet comprises: a low density portion; a plurality of high density portions spaced apart from one another within the low density portion; The area ratio of the plurality of high density portions in the first sheet is different from the area ratio of the plurality of high density portions in the second sheet. The pants-type absorbent article according to any one of claims 1 to 14.

17. the plurality of thermoplastic sheets includes a first sheet and a second sheet; The first sheet comprises: a low density portion; a plurality of high density portions spaced apart from one another within the low density portion; The second sheet comprises: a low density portion; a plurality of high density portions spaced apart from one another within the low density portion; The pattern of the plurality of high-density portions of the first sheet and the pattern of the plurality of high-density portions of the second sheet are different. The pants-type absorbent article according to any one of claims 1 to 14.

18. the plurality of thermoplastic sheets includes a first sheet and a second sheet; The fiber orientation degree of the first sheet and the fiber orientation degree of the second sheet are different. The pants-type absorbent article according to any one of claims 1 to 14.

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