Pants-type disposable wearable article

Abstract

To improve wearing feeding and appearance of a width wide part.SOLUTION: A wearing article is configured so that an intermediate part M whose both side edges are edges 29 of leg openings, has a wide width part V whose width becomes gradually wider as going to a waist part T from a crotch part, the wide width part V has: a side non-stretchable region A1 provided on each of both side parts; and an intermediate stretchable region A2 which is adjacent to the side non-stretchable regions A1 and is stretched / shrunk in a width direction WD with the intermediate elastic member 26. The intermediate elastic member 26 has: a first part 26a fixed in the intermediate stretchable region A2; and a non fixed second part 26b which is in the side non-stretchable region A1. A side edge of the wide width part V passes a position which is separated outward from a virtual circle VC whose radius is equal to a natural length of the second part 26b and whose center is a boundary between the first and second parts 26a, 26b. The underpants type disposable wearing article is configured so that there is provided a junction 23 on an edge region A3 which is parallel to the side edge of the wide width part V and is between the virtual line VL and the side edge of the wide width part V which are separated each other by a shortest distance between the side edge of the wide width part V and the virtual circle VC.SELECTED DRAWING: Figure 8

Description

Technical Field

[0001] The present invention relates to a pants-type disposable wearable article.

Background Art

[0002] Pants-type disposable diapers, pants-type disposable sanitary napkins, pants-type disposable diaper covers, and other pants-type disposable wearable articles have an annular body circumference portion and an intermediate portion that extends from the body circumference portion of the front body to the body circumference portion of the back body via the crotch portion. Leg openings are formed on both sides of the intermediate portion, and a waist opening is formed above the body circumference portion.

[0003] In such pants-type disposable diapers, in order to improve the fit to the wearer's body surface, the body circumference portion and the intermediate portion are formed into a laminated structure having a plurality of sheet layers, and between the sheet layers, elongated elastic members along the width direction are attached at intervals in the front-rear direction in a state of being extended in the width direction to make it stretchable (see, for example, Patent Documents 1 to 3).

[0004] Further, in order to cover the buttocks and groin areas more widely, the intermediate portion is known to have a portion with the narrowest width at the crotch portion and a widened portion whose width gradually increases from there to the body circumference portion (see, for example, Patent Document 3). In this case, both side edges of the intermediate portion become the edges of the leg openings.

[0005] However, if the elastic member along the width direction provided in the widened portion is fixed up to the side edge or its vicinity, the side edge of the widened portion becomes a wavy shape, which significantly affects the wearing feeling and appearance.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0007] Therefore, the main problem of the present invention is to improve the wearing feeling and appearance of the widened portion.

Means for Solving the Problems

[0008] The pant-type disposable wearing article that solves the above problems is as follows. <First Aspect> It has a body circumference portion formed in a ring shape, an intermediate portion that continues from the lower edge of the body circumference portion at the front body to the crotch portion and then to the lower edge of the body circumference portion at the back body, leg openings formed on both sides of the intermediate portion, and a waist opening formed above the body circumference portion. Both side edges of the intermediate portion form the edges of the leg openings. The intermediate portion has a portion with the narrowest width at the crotch portion, and has a widened portion that gradually widens from there to the body circumference portion at the front body and the body circumference portion at the back body. At least one of the widened portions of the front body and the back body has a side non-stretch region provided on both sides, an intermediate stretch region adjacent to the center side in the width direction of the side non-stretch region, a first portion located within the intermediate stretch region, and a second portion located within the side non-stretch region. It has an elongated intermediate elastic member extending along the width direction, a first sheet extending over the side non-stretch region and the intermediate stretch region so as to cover the front side of the intermediate elastic member, a second sheet extending over the side non-stretch region and the intermediate stretch region so as to cover the back side of the intermediate elastic member, and a joining portion where the first sheet and the second sheet are joined, provided at least at intervals in the front-rear direction. The intermediate stretch region has fixing portions that fix at least both end portions of the first portion and at least one of the first sheet and the second sheet so as to stretch in the width direction together with the intermediate elastic member. The second part is not fixed to the first sheet and the second sheet and is contracted to its natural length. The side edges of the widened part have a shape that passes through a position away from the outside of a virtual circle with a radius equal to the natural length of the second part centered on the boundary between the first part and the second part. Parallel to the side edges of the widened part, in the edge region between the virtual line separated by the shortest distance between the side edges of the widened part and the virtual circle and the side edges of the widened part, the joining part is provided. A pant-type disposable wearable article, characterized in that.

[0009] (Function and effect) In this pant-type disposable wearable article, in the widened part, side non-stretch regions are provided on both sides, and an intermediate stretch region is provided adjacent to the central side in the width direction. Therefore, while ensuring the fit by the intermediate stretch region, the side edges of the widened part do not have a wavy shape, and the influence on the wearing feeling and appearance is small. And in order to provide such side non-stretch regions, it is necessary to contract the second part of the intermediate elastic member to its natural length without fixing it to the first sheet and the second sheet. In that case, however, at the side edges of the widened part, the first sheet and the second sheet open, and the unfixed second part of the intermediate elastic member may protrude, deteriorating the wearing feeling and appearance. However, in this pant-type disposable wearable article, since the joining part of the first sheet and the second sheet is located at a position sufficiently far from the root of the second part, it is difficult for the first sheet and the second sheet to open at the side edges of the widened part, and even if they open slightly, it is difficult for the second part of the intermediate elastic member to protrude.

[0010] <Second aspect> When the side in the width direction is set to 0° when viewed from the center of the virtual circle, the edge region has at least one joining part in the range from the 15° direction on the body circumference side to the 90° direction on the opposite side. The pant-type disposable wearable article of the first aspect.

[0011] (Function and effect) Since the second part of the intermediate elastic member often faces sideways before use and is likely to move toward the crotch side during wearing, having a joint within the scope of this aspect makes it difficult for the first and second sheets at the side edges of the widened portion to open at positions close to the second part of the intermediate elastic member. Even if the first and second sheets open slightly in the portion without the joint, it becomes difficult for the second part of the intermediate elastic member to be exposed there.

[0012] <Third Aspect> A plurality of the intermediate elastic members are provided in the widened portion at intervals in the front-rear direction. When the side in the width direction is set to 0° when viewed from the center of the virtual circle in each intermediate elastic member, the edge region has one joint each in the range from 0° to 15° in the direction of the body circumference side and in the range from 0° to 90° in the direction opposite to the body circumference side. Among the intermediate elastic members adjacent to each other in the front-rear direction, when the side in the width direction is set to 0° when viewed from the center of the virtual circle in the intermediate elastic member on the body circumference side, the joint of the edge region located in the range from 0° to 90° in the direction opposite to the body circumference side and, when the side in the width direction is set to 0° when viewed from the center of the virtual circle in the intermediate elastic member on the side opposite to the body circumference side, the joint of the edge region located in the range from 0° to 15° in the direction of the body circumference side are the same joint. Pant-type disposable wearing article of the second aspect.

[0013] (Function and Effect) When a plurality of intermediate elastic members are provided in the widened portion, by arranging the joints in the edge region as in this aspect, with the minimum number of joints, it becomes difficult for the first and second sheets at the side edges of the widened portion to open, and even if the first and second sheets open slightly in the portion without the joint, it becomes difficult for the second part of the intermediate elastic member to be exposed there. Therefore, it is possible to suppress a decrease in flexibility due to providing joints in the edge region.

[0014] <Fourth Aspect> The joint portion includes a pair of first joint portions that are in close contact with both the front and rear sides of the first portion, and a second joint portion that is located in the side non-stretchable region. The pair of first joint portions are repeatedly provided at intervals in the width direction. The fixing portion is a cylindrical portion composed of the pair of first joint portions and the portion located between the pair of first joint portions among the first sheet and the second sheet. The second joint portion is repeatedly provided at intervals in the front-rear direction and the width direction within the side non-stretchable region. The side non-stretchable region has a first region that is located on the front side and has a radius equal to or less than that of the virtual circle from a virtual extension portion that extends the first portion laterally along the width direction, and a second region that is located on the rear side and has a radius equal to or less than that of the virtual circle from the virtual extension portion. The second joint portion is provided in each of the first region and the second region. At least one of the second joint portion located in the first region and the second joint portion located in the second region is located in the edge region. The interval in the width direction between the pair of first joint portions located on the outermost side and the second joint portion adjacent to it on the side, and the interval between the second joint portions adjacent to each other in the width direction are equal and are equal to or less than the radius of the virtual circle. A pant-type disposable wearing article according to any one of the first to third aspects.

[0015] (Function and effect) In this aspect, it is preferable because there is little difference in appearance between the side non-stretchable region and the intermediate stretchable region, and the flexibility of the intermediate stretchable region is also excellent.

[0016] <The fifth aspect> The area of each of the second joint portions is the same as or smaller than the area of the first joint portion. The area ratio of the second joint portion in the side non-stretchable region is smaller than the area ratio of the first joint portion in the intermediate stretchable region. A pant-type disposable wearing article according to the fourth aspect.

[0017] (Function and effect) As in this embodiment, it is preferable to provide the second joint portion smaller and sparser than the first joint portion, because the side non-stretchable region near the edge of the widened portion can be made flexible.

[0018] <Sixth Aspect> The side edge of the widened portion has a curved portion whose center of curvature is located inside, spanning both front and rear sides of a virtual extension portion obtained by laterally extending at least one of the first portions along the width direction. A pants-type disposable wearing article according to any one of the first to fifth aspects.

[0019] (Function and Effect) It is preferable that the side edge of the widened portion has a shape as in this embodiment, because it is easy to secure a wide edge region.

Effect of the Invention

[0020] As described above, according to the present invention, advantages such as an improved wearing feeling and appearance of the widened portion are brought about.

Brief Description of the Drawings

[0021]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Embodiments for Carrying Out the Invention

[0022] Hereinafter, as an example of a pants-type disposable wearing article, a pants-type disposable diaper will be described in detail with reference to the accompanying drawings. In the drawings, the dotted pattern portions indicate joining means such as hot melt adhesives.

[0023] FIGS. 1 to 8 show an example of a pants-type disposable diaper. This pants-type disposable diaper has a body circumference portion T formed in a ring shape, an intermediate portion M extending from the lower edge of the body circumference portion T of the front part F through the crotch portion to the lower edge of the body circumference portion T of the back part B, leg openings LO formed on both sides of the intermediate portion M, and a waist opening WO formed above the body circumference portion T. The intermediate portion M has a portion with the narrowest width at the crotch portion and has a widened portion V that gradually widens from there to the body circumference portion T of the front part F and the body circumference portion T of the back part B. Both side edges of the intermediate portion M form the edges 29 of the leg openings.

[0024] The pant-type disposable diaper is mainly formed by two assemblies, namely an outer body 20 and an inner body 10, and each part of the pant-type disposable diaper is formed by at least one of these assemblies. The inner body 10 preferably extends from the torso circumference part T of the front body F through the crotch part to the torso circumference part T of the back body B. At the torso circumference part T of the front body F and the torso circumference part T of the back body B, the outer body 20 extends laterally beyond both side edges of the inner body 10, and both side edges of the outer body 20 of the front body F and both side edges of the outer body 20 of the back body B are joined by joining means such as welding or a hot melt adhesive to form a side seal part 21, whereby it is preferable that the torso circumference part T, the waist opening WO, and the leg opening LO are formed. Also, in the widened part V, the outer body 20 extends laterally beyond both side edges of the inner body 10, and it is preferable that the part from the side edge of the widened part V to the side edge of the inner body 10 is formed only by the outer body 20. Furthermore, the outer body 20 extends to both the front and rear sides of the inner body 10, and its front and rear ends preferably form the edge of the waist opening WO. In the illustrated example, the outer body 20 is continuous in the front-rear direction LD from the torso circumference part T of the front body F to the torso circumference part T of the back body B, but it may also have a front outer body extending from the torso circumference part T of the front body F to the widened part V of the front body F and a rear outer body extending from the torso circumference part T of the back body B to the widened part V of the back body B separately with a space in the front-rear direction LD (not shown).

[0025] (Structural example of the inner body) As shown in FIGS. 4 to 6, the inner body 10 has a basic structure in which an absorber 18 is interposed between a liquid-permeable top sheet 11 and a liquid-impermeable sheet 12, and absorbs and retains the excreted liquid that has passed through the top sheet 11. The planar shape of the inner body 10 is not particularly limited, but it is generally substantially rectangular as in the illustrated example. Both side edges of the inner body 10 in the illustrated example are located outside the side edge of the outer body 20 in the width direction WD at the crotch part, but they may coincide with the side edge of the outer body 20 or may be located on the center side in the width direction WD of the side edge of the outer body 20.

[0026] The absorber 18 may have a single-layer structure or a multi-layer structure. Preferably, the absorber 18 is a member containing superabsorbent polymer particles, and more preferably, it is a mixed aggregate of hydrophilic short fibers such as pulp fibers and superabsorbent polymer particles. The absorber 18 can be packaged with a packaging sheet 14 having liquid permeability and liquid retention properties, such as crepe paper, for the purpose of shape and polymer retention, etc.

[0027] As the superabsorbent polymer particles, those used in this type of absorbent article can be used as they are. For example, it is desirable that the proportion of particles remaining on the sieve in sieving (shaking for 5 minutes) using a 500 μm standard sieve (JIS Z8801-1:2006) is 30% by weight or less, and it is also desirable that the proportion of particles remaining on the sieve in sieving (shaking for 5 minutes) using a 180 μm standard sieve (JIS Z8801-1:2006) is 60% by weight or more.

[0028] The superabsorbent polymer particles are not particularly limited, but those with a water absorption rate of 35 to 60 seconds and a water absorption amount of 50 to 70 g / g can be preferably used. As the superabsorbent polymer particles, there are those such as starch-based, cellulose-based, and synthetic polymer-based ones. Preferably, starch-acrylic acid (salt) graft copolymers, saponified products of starch-acrylonitrile copolymers, cross-linked products of sodium carboxymethyl cellulose, acrylic acid (salt) polymers, etc. can be used. The basis weight of the superabsorbent polymer particles can be appropriately determined according to the absorption amount required for the product. Therefore, although it cannot be generally stated, it can be 100 to 350 g / m 2 can be set.

[0029] The shape of the absorber 18 can be appropriately determined. It can be rectangular, but preferably, it has a constricted portion 13 that is narrower in width than the front and rear sides on both sides of the crotch portion. The dimensions of the constricted portion 13 can be appropriately determined, but the width of the narrowest part can be about 40 to 60% of the total width of the absorber 18.

[0030] As the topsheet 11 disposed on the front side (skin-contact side) of the absorber 18, a perforated or non-perforated nonwoven fabric, a perforated plastic sheet, etc. are preferably used. The material fibers constituting the nonwoven fabric can be synthetic fibers such as polyolefin-based fibers such as polyethylene or polypropylene, polyester-based fibers, polyamide-based fibers, etc., regenerated fibers such as rayon or cupra, and natural fibers such as cotton, and nonwoven fabrics obtained by appropriate processing methods such as the spunlace method, the spunbond method, the thermal bond method, the meltblown method, the needle punch method, etc. can be used. Among these processing methods, the spunlace method is excellent in terms of being rich in flexibility and drapability, and the thermal bond method is excellent in terms of being bulky and soft. When a large number of through holes are formed in the topsheet 11, urine, etc. can be quickly absorbed. In the illustrated example, the topsheet 11 extends to the back side of the absorber 18 by enclosing the side edge portion of the absorber 18.

[0031] As the liquid-impermeable sheet 12 disposed on the back side (non-skin-contact side) of the absorber 18, a liquid-impermeable plastic sheet such as polyethylene or polypropylene is used, but in recent years, those having moisture permeability are preferably used from the viewpoint of preventing stuffiness. As this water-blocking and moisture-permeable sheet, for example, a microporous sheet obtained by melt-kneading inorganic fine particles such as calcium carbonate in an olefin resin such as polyethylene or polypropylene to form a sheet and then stretching it in the uniaxial or biaxial direction can be preferably used. In the illustrated example, the liquid-impermeable sheet 12 is folded back to the back side on both sides in the width direction WD of the absorber 18 together with the topsheet 11, but it is not limited to such a structure, and other known structures can be adopted.

[0032] Three-dimensional gathers BS that fit around the legs are formed on both sides of the interior body 10. As shown in FIGS. 5 and 6, this three-dimensional gather BS includes a fixing portion fixed to the side portion of the back surface of the interior body 10, a main body portion extending from this fixing portion through the side of the interior body to the side portion of the front surface of the interior body, a fallen portion formed by fixing the front and rear end portions of the main body portion in a fallen state to the side portion of the front surface of the interior body, and a free portion formed by making the space between these fallen portions non-fixed. It is formed by a three-dimensional gather sheet 15 that is folded into a double sheet. An elongated gather elastic member 16 is disposed between the double sheets at the tip of the free portion and the like. With such a structure, in the three-dimensional gather BS, the free portion protruding from the side edge of the absorber rises as shown by the two-dot chain line in FIG. 5 in the product state due to the contraction of the gather elastic member 16. As the three-dimensional gather sheet 15, a water-repellent non-woven fabric is preferably used.

[0033] As the gather elastic member 16, materials such as commonly used styrene-based rubber, polyolefin-based rubber, urethane-based rubber, ester-based rubber, polyurethane, polyethylene, polystyrene, styrene butadiene, silicone, and polyester can be used. Also, in order to make it difficult to see from the outside, it is preferably arranged with a thickness of 925 dtex or less, an elongation rate of 150 to 350%, and a spacing of 7.0 mm or less. Note that as the gather elastic member 16, in addition to the thread-like form shown in the illustrated embodiment, a tape-like member having a certain width can also be used.

[0034] The material fibers constituting the three-dimensional gathered sheet 15 described above can also be synthetic fibers such as polyolefins such as polyethylene or polypropylene, polyesters, polyamides, etc., regenerated fibers such as rayon and cupra, natural fibers such as cotton, etc. Non-woven fabrics obtained by appropriate processing methods such as the spunbond method, thermal bond method, meltblown method, needle punch method, etc. can be used, but in particular, it is preferable to use a non-woven fabric with a suppressed basis weight and excellent air permeability in order to prevent stuffiness. Further, for the three-dimensional gathered sheet 15, in order to prevent the penetration of urine, etc., and to prevent chafing and enhance the tactile sensation (dry feeling) on the skin, it is desirable to use a water-repellent treated non-woven fabric coated with a silicone-based, paraffin metal-based, alkyl chromic chloride-based water repellent, etc.

[0035] (Structural example of the exterior body) As shown in FIGS. 4 to 6, the exterior body 20 has a first sheet 20A arranged on the front side, a second sheet 20B arranged on the back side, and between these first sheet 20A and second sheet 20B, and a folded portion 20C formed by folding the second sheet 20B back to the inner surface side at the waist opening edge. It has an elastic member arranged between them, and the exterior body 20 is provided with elasticity by the contraction force of the elastic member causing the exterior body 20 to contract in the natural length state. The planar shape is generally in an hourglass shape as a whole such that both sides in the width direction WD of the intermediate portion form the edges 29 of the leg openings. The first sheet 20A and the second sheet 20B may be one layer and the other layer in which a single sheet is folded and overlapped at the edge of the waist opening WO and the edge 29 of the leg opening.

[0036] The outer body 20 in the illustrated example includes a waist elastic member 24 disposed at the waist portion W in the annular body circumference portion T formed by joining the front body portion F and the rear body portion B, a lower waist elastic member 25 disposed at the lower waist portion U on the crotch side of the waist portion W in the body circumference portion T, and an intermediate elastic member 26 disposed at the intermediate portion M. In the outer body 20 of the illustrated example, there is no elongated elastic member that is continuous from the side seal portion 21 of the front body portion F to the side seal portion 21 of the rear body portion B along the edge 29 of the leg opening. Also, there is no elongated elastic member that extends from each side seal portion 21 along the edge 29 of the leg opening to the crotch portion.

[0037] The waist elastic member 24 is an elongated elastic member along the width direction WD in which a plurality of them are arranged at intervals in the front-rear direction LD at the waist portion W, and is fixed in a state of being extended in the width direction WD at a predetermined elongation rate. As this waist elastic member 24, in addition to yarn rubber, a tape-like stretchable member may be used. Also, the waist elastic member 24 in the illustrated example is sandwiched between non-woven fabrics at the folded-back portion 20C of the second sheet 20B at the waist portion W and is fixed to the second sheet 20B, but it may be sandwiched between the first sheet 20A and the second sheet 20B and fixed to at least one of the first sheet 20A and the second sheet 20B. As an example, the waist elastic member 24 can be provided with about 3 to 10 spandex yarn rubbers having a thickness of about 620 to 1240 dtex at intervals of about 3 to 8 mm. Also, the waist portion W contracts in the width direction WD in a natural length state together with the waist elastic member 24, and it is preferably that the maximum elongation in the width direction WD in the unfolded state is 160 to 320%.

[0038] The lower waist elastic member 25 is an elongated elastic member along the width direction WD, which is arranged in plurality at intervals in the front-rear direction LD between the first sheet 20A and the second sheet 20B in the lower waist portion U, and is fixed to at least one of the first sheet 20A and the second sheet 20B in a state of being stretched in the width direction WD at a predetermined elongation rate. As an example, the lower waist elastic member 25 can be provided with about 10 to 25 spandex yarn rubbers having a thickness of about 310 to 1240 dtex at intervals of about 5 to 20 mm. Further, the lower waist portion U contracts in the width direction WD in a natural length state together with the lower waist elastic member 25, and it is preferable that the maximum elongation in the width direction WD in the unfolded state is 160 to 320%. Note that the boundary between the waist elastic member 24 and the lower waist elastic member 25 does not necessarily have to be clear. For example, among the elastic members arranged at intervals in the front-rear direction LD in the body circumference portion T, even if the number cannot be specified, as long as several upper ones function as the waist elastic member 24 and the remaining elastic members function as the lower waist elastic member 25.

[0039] The intermediate elastic member 26 is an elongated elastic member along the width direction WD, which is arranged singly or in plurality at intervals in the front-rear direction LD between the first sheet 20A and the second sheet 20B in the intermediate portion M, and is fixed to at least one of the first sheet 20A and the second sheet 20B in a state of being stretched in the width direction WD at a predetermined elongation rate. As an example, the intermediate elastic member 26 can be provided with about 1 to 10 spandex yarn rubbers having a thickness of about 310 to 1240 dtex at intervals of about 5 to 20 mm. Further, the intermediate portion M contracts in the width direction WD in a natural length state together with the intermediate elastic member 26, and it is preferable that the maximum elongation in the width direction WD in the unfolded state is 160 to 320%.

[0040] As shown in FIG. 2, after the lower waist elastic member 25 and the intermediate elastic member 26 are continuously fixed to the exterior body 20 during manufacturing, the middle in the width direction WD of the portion overlapping the absorber 18 is finely cut in a predetermined cutting pattern or the like to form a non-elastic region where the contraction forces of the elastic members 25 and 26 do not substantially act, and the portions extending laterally from this non-elastic region are set as elastic regions where the contraction forces of the elastic members 25 and 26 act (that is, regions that elastically expand and contract together with the lower waist elastic member 25 and the intermediate elastic member 26). Thereby, unnecessary contraction in the width direction WD of the interior body 10 (particularly the absorber 18) can be prevented. Of course, although not shown, the lower waist elastic member 25 and the intermediate elastic member 26 may be continuous across the interior body 10.

[0041] Unlike the illustrated example, the intermediate elastic member 26 may be provided only in the front body part F or the back body part B.

[0042] As shown in FIGS. 2, 7, and 8, the exterior body 20 has joining portions 22 and 23 where a first sheet 20A and a second sheet 20B are joined, provided at least at intervals in the front-rear direction LD. The joining portions 22 and 23 can be formed by a hot melt adhesive, but can also be formed by welding means such as heat sealing or ultrasonic sealing (that is, the welded portions of the first sheet 20A and the second sheet 20B). These joining portions 22 and 23 may be continuous in the width direction WD, but as in the illustrated example, if they are provided at intervals in the width direction WD as well, it is preferable in terms of being more flexible.

[0043] The joints 22 and 23 may be provided in close contact with or away from both the front and rear sides of the elastic members 24 to 26. Such joints 22 and 23 are suitable for welding because the first sheet 20A and the second sheet 20B are joined without passing through the elastic members 24 to 26. For example, pairs of joints 22 that are in close contact with both the front and rear sides of the elastic members 25 and 26 are repeatedly provided at intervals in the width direction WD on the first sheet 20A and the second sheet 20B. Among the first sheet 20A and the second sheet 20B, it is preferable to adopt a structure in which the elastic members 25 and 26 are clamped and fixed from the periphery by a cylindrical fixing portion 27 composed of a pair of joints 22 and the portion located therebetween (the first structure). This is the same structure as that described in Patent Document 2, and has the advantage that the elastic members 25 and 26 can also be fixed to the first sheet 20A and the second sheet 20B by forming the joints 22 of the first sheet 20A and the second sheet 20B. The fixing portions 27 are preferably provided at intervals in the front-rear direction LD (that is, the fixing portions 27 adjacent to each other in the front-rear direction LD are separated). The interval d1 (see FIG. 12) in the front-rear direction LD of the fixing portions 27 can be determined as appropriate, and for example, it can be set to 0.70 to 0.95 times the interval d2 (see FIG. 12) between the elastic members 25 and 26 adjacent to each other in the front-rear direction LD. In the illustrated expansion and contraction region, only pairs of joints 22 in close contact with the front and rear of the elastic members 25 and 26 are provided. Along with this, as shown in FIG. 10, joints 23 can also be provided at positions separated from the elastic members 25 and 26 in the front-rear direction LD (for example, approximately at the center of the region between adjacent elastic members 25 and 26, etc.).

[0044] Although not shown, in the first structure, the surface of the portion located between the pairs of joints 22 in the elastic members 25 and 26 may not be welded to the first sheet 20A and the second sheet 20B, but it is preferable if it is welded to at least one of the first sheet 20A and the second sheet 20B because the fixing of the elastic members 25 and 26 becomes stronger (the second structure). Instead of this, or together with this, a hot melt adhesive may be applied to the outer peripheral surface of the elastic members 25 and 26 at appropriate positions such as between the pairs of joints 22 in the elastic members 25 and 26 or at both ends of the expansion and contraction region to reinforce the fixing of the elastic members 25 and 26 to the first sheet 20A and the second sheet 20B (the third structure).

[0045] Although not shown, a joint portion 23 for welding the first sheet 20A and the second sheet 20B without passing through the elastic members 24 to 26 is provided only at a position separated from the elastic members 24 to 26 in the longitudinal direction LD (for example, approximately at the center of the region between the elastic members 24 to 26 adjacent to each other in the longitudinal direction LD). A fixing portion 27 for fixing the elastic members 24 to 26 to at least one of the first sheet 20A and the second sheet 20B with a hot melt adhesive can also be provided only at both ends of the expansion and contraction region (the fourth structure). The example shown in FIG. 10 in which the pair of joint portions 22 is omitted corresponds to this fourth structure.

[0046] On the other hand, although not shown, the joint portion may be provided at a position overlapping the elastic members 24 to 26. Since the first sheet 20A and the second sheet 20B are joined through the elastic members 24 to 26, such a joint portion is suitable for the use of a hot melt adhesive. More specifically, by applying the hot melt adhesive only to the outer peripheral surfaces of the elastic members 24 to 26 by an application means such as a com gun or a sure lap nozzle and sandwiching the first sheet 20A and the second sheet 20B therebetween, only the hot melt adhesive applied to the outer peripheral surfaces of the elastic members 24 to 26 can be used to fix the elastic members 24 to 26 to the first sheet 20A and the second sheet 20B and to form a joint portion of the first sheet 20A and the second sheet 20B (the fifth structure). In this case, the joint portions (the hot melt adhesive application portions) can be provided at intervals in the width direction WD, or can be provided continuously in the width direction WD.

[0047] The dimensions and intervals of the joints 22 and 23 can be determined as appropriate. As an example, the dimension y1 (see FIG. 12) in the longitudinal direction LD of the joint 22 can be 0.5 to 3.0 mm. Also, the interval d3 (see FIG. 12) in the longitudinal direction LD between the pair of joints 22 in the first structure is shorter than the dimension in the longitudinal direction LD at the natural length of the elastic members 25 and 26, and can be, for example, about 0.55 to 0.80 times. The interval y2 (see FIG. 12) in the longitudinal direction LD between the other adjacent joints 22 and 23 can be 0 to 19 mm. In the first to fourth structures, when the joints 22 and 23 are arranged at intervals in the width direction WD, the arrangement of the joints 22 and 23 is not particularly limited. In addition to being in a matrix shape as in the illustrated example, an arrangement in which the positions in the width direction WD are shifted (for example, in a staggered pattern) can also be adopted. In this case, the dimension w1 (see FIG. 12) in the width direction WD of the joints 22 and 23 can be 0.2 to 1.5 mm, and the interval w2 (see FIG. 12) in the width direction WD can be 3.5 to 8.0 mm.

[0048] The joint structure of the first sheet 20A and the second sheet 20B in the exterior body 20 and the fixing structure of the elastic members 24 to 26 may be the same in all of the waist part W, the lower waist part U, and the middle part M, or may be different only in part. For example, the waist part W may adopt the fifth structure, and any one of the first to fourth structures may be adopted in the lower waist part U and the middle part M.

[0049] (Width-expanding part) Characteristically, as shown in FIGS. 7 and 8, the widened portions V of the front body F and the back body B include a first sheet 20A and a second sheet 20B extending over the entire width direction WD, an intermediate elastic member 26 sandwiched therebetween, and joints 22, 23 where the first sheet 20A and the second sheet 20B are joined, provided at least spaced apart in the front-rear direction LD. These widened portions V have side non-stretchable regions A1 provided on both sides and an intermediate stretchable region A2 adjacent to the center side in the width direction WD of the side non-stretchable regions A1. The boundary D between the side non-stretchable region A1 and the intermediate stretchable region A2 is shown by a two-dot chain line in the figure. The intermediate elastic member 26 has a first portion 26a located within the intermediate stretchable region A2 and a second portion 26b located within the side non-stretchable region A1. Further, the intermediate stretchable region A2 has fixing portions 27 that fix at least both ends of the first portion 26a and at least one of the first sheet 20A and the second sheet 20B so as to stretch and contract in the width direction WD together with the intermediate elastic member 26, and the second portion 26b is contracted to its natural length without being fixed to the first sheet 20A and the second sheet 20B. That is, the second portion 26b can move freely between the first sheet 20A and the second sheet 20B. Furthermore, the side edge of the widened portion V (corresponding to the edge 29 of the leg opening in the illustrated example) has a shape passing through a position outside a virtual circle VC having a radius equal to the natural length of the second portion 26b centered on the boundary between the first portion 26a and the second portion 26b, and a joint 23 is provided in an edge region A3 between a virtual line VL parallel to the side edge of the widened portion V and spaced apart from the side edge of the widened portion V by the shortest distance between the side edge of the widened portion V and the virtual circle VC (when there are a plurality of virtual circles VC as in the illustrated example, it means the shortest distance between the virtual circle VC closest to the widened portion V and the side edge of the widened portion V). The length of the second portion 26b is approximately equal to the value obtained by dividing the dimension in the width direction WD from the boundary between the first portion 26a and the second portion 26b to the side edge of the widened portion V by the magnification at the time of attachment of the intermediate elastic member 26.

[0050] Thus, when the side non-stretchable regions A1 are provided on both sides of the widened portion V and the intermediate stretchable region A2 is provided adjacent to the center side in the width direction WD thereof, the intermediate stretchable region A2 ensures the fitness while the side edges of the widened portion V do not have a wavy shape, and the influence on the wearing feeling and appearance is small. And, in order to provide such side non-stretchable regions A1, it is necessary to contract the second portion 26b of the intermediate elastic member 26 to its natural length without fixing it to the first sheet 20A and the second sheet 20B. However, in that case, the first sheet 20A and the second sheet 20B may open at the side edge of the widened portion V, and the unfixed second portion 26b of the intermediate elastic member 26 may protrude, which may deteriorate the wearing feeling and appearance. However, as in the illustrated example, when the joint portion 23 of the first sheet 20A and the second sheet 20B is provided at a position sufficiently separated from the root of the second portion 26b, the first sheet 20A and the second sheet 20B are difficult to open at the side edge of the widened portion V, and even if they open slightly, the second portion 26b of the intermediate elastic member 26 is difficult to protrude.

[0051] The position of the joint 23 in the edge region A3 can be determined as appropriate. One preferred example is, as shown enlarged in FIG. 11, when the side in the width direction WD is set to 0° when viewed from the center of the virtual circle VC, in the range from the direction of 15° on the body circumference part T side to the direction of 90° on the opposite side (more preferably, in the range from the direction of 10° on the body circumference part T side to the direction of 80° on the opposite side) of the edge region A3, there is at least one joint 23. Since the second part 26b of the intermediate elastic member 26 often faces sideways before use and is likely to move toward the crotch side during wearing, having the joint 23 within the scope of this aspect makes it difficult for the first sheet 20A and the second sheet 20B at the side edges of the widened part V to open at a position close to the second part 26b of the intermediate elastic member 26. Also, even if the first sheet 20A and the second sheet 20B open somewhat at a part without the joint 23, it becomes difficult for the second part 26b of the intermediate elastic member 26 to be exposed there. For this reason, it is more preferable that the edge region A3 has one joint 23 each in the range from 0° to the direction of 15° on the body circumference part T side and in the range from 0° to the direction of 90° on the side opposite to the body circumference part T side when the side in the width direction WD is set to 0° when viewed from the center of the virtual circle VC. In particular, when a plurality of intermediate elastic members 26 are provided at intervals in the front-rear direction LD in the widened part V, among the intermediate elastic members 26 adjacent to each other in the front-rear direction LD, when the side in the width direction WD is set to 0° when viewed from the center of the virtual circle VC in the intermediate elastic member 26 on the body circumference part T side, the joint 23 in the edge region A3 located in the range from 0° to the direction of 90° on the side opposite to the body circumference part T side and the joint 23 in the edge region A3 located in the range from 0° to the direction of 15° on the body circumference part T side in the intermediate elastic member 26 on the opposite side being the same joint 23 is preferable because the number of joints 23 in the edge region A3 is minimized and a decrease in flexibility due to providing the joint 23 in the edge region A3 can be suppressed.

[0052] The joints 22 and 23 provided in the region of the widening portion V excluding the edge region A3 may have any of the aforementioned first to fifth structures. However, as in the illustrated example, the first or second structure is preferable in terms of flexibility. More specifically, for the illustrated example, the joints 22 and 23 of the widening portion V include a pair of first joints 22 that are in close contact with both the front and rear sides of the first portion 26a, and a second joint 23 located in the side non-stretchable region A1. The pair of first joints 22 are repeatedly provided at intervals in the width direction WD. The fixing portion 27 is a cylindrical portion formed by the pair of first joints 22 and the portion located between the pair of first joints 22, among the first sheet 20A and the second sheet 20B. The second joint 23 is repeatedly provided at intervals in the front-rear direction LD and the width direction WD within the side non-stretchable region A1. Also, in the side non-stretchable region A1, a first region h1 that is equal to or less than the radius of the virtual circle VC from the virtual extension portion obtained by laterally extending the first portion 26a along the width direction WD to the front side, and a second region h2 that is equal to or less than the radius of the virtual circle VC from the virtual extension portion to the rear side each have the second joint 23, and at least one of the second joints 23 located in the first region and the second joints 23 located in the second region is located in the edge region A3. Further, the interval in the width direction WD between the pair of first joints 22 located most laterally and the second joint 23 adjacent to it laterally, and the interval between the second joints 23 adjacent to each other in the width direction WD are equal and are equal to or less than the radius of the virtual circle VC. As a result, in the illustrated example, the difference in appearance between the side non-stretchable region A1 and the intermediate stretchable region A2 is small, and the flexibility of the intermediate stretchable region A2 is also excellent.

[0053] In particular, as in the illustrated example, when the area of each second joint 23 is the same as or smaller than the area of the first joint 22, and the area ratio of the second joint 23 in the side non-stretchable region A1 is smaller than the area ratio of the first joint 22 in the intermediate stretchable region A2, the side non-stretchable region A1 near the edge of the widening portion V is becomes flexible, which is preferable.

[0054] In the examples shown in FIGS. 7 and 8, the second joint 23 located in the side non-stretchable region A1 is also provided in portions other than the edge region A3, but may be provided only in the edge region A3 as shown in FIG. 9.

[0055] On the other hand, the side edge of the widened portion V may be a curve whose center of curvature is located only outside the side edge, like the widened portion V of the front body F shown in FIG. 7. However, like the widened portion V of the back body B shown in FIG. 8, if it has a curved portion whose center of curvature is located inside, extending at least one first portion 26a laterally along the width direction WD, over both the front and rear sides of the virtual extension portion, it is preferable because it is easy to widely secure the edge region A3. That is, in the widened portion V of the front body F, it may have a curved portion whose center of curvature is located inside, extending over both the front and rear sides of the virtual extension portion obtained by laterally extending at least one first portion 26a along the width direction WD. In this case, in the widened portion V of the back body B, it may be a curve whose center of curvature is located only outside the side edge.

[0056] In the illustrated example, both the widened portions V of the front body F and the back body B have the side non-stretchable regions A1. However, either one (for example, the front body F) may not have the side non-stretchable region A1 (that is, the entire width direction WD becomes the intermediate stretchable region A2). Also, in the illustrated example, both the front body F and the back body B have the widened portions V and the intermediate stretchable regions A2. However, either one (for example, the front body F) may not have the widened portion V, or may not have the intermediate stretchable region A2 even if it has the widened portion V.

[0057] <Explanation of Terms in the Specification> When the following terms are used in the specification, unless otherwise specified in the specification, they have the following meanings. · The "front-rear direction" means the direction indicated by the symbol LD in the figure (vertical direction), the "width direction" means the direction indicated by WD in the figure (left-right direction), and the front-rear direction and the width direction are orthogonal to each other. · The "deployed state" means a state where it is deployed flat without shrinkage (including any shrinkage such as shrinkage by an elastic member) or slack.

[0058] · The "front side" means the side closer to the wearer's skin when worn, and the "back side" means the side farther from the wearer's skin when worn.

[0059] · "Surface" means the "front" surface, and "back surface" means the "rear" surface.

[0060] · "Area ratio" means the ratio of the target part to the unit area, and is expressed as a percentage by dividing the total area of the target part (for example, the joint part) in the target area (for example, the intermediate expansion area) by the area of the target area. In the form where a large number of target parts are provided at intervals, it is desirable to set the target area to a size that includes 10 or more target parts and calculate the area ratio. For example, the area ratio of the joint part can be measured by the following procedure using, for example, the product name VHX-1000 of KEYENCE and setting the measurement condition to 20 times. (1) Set it on a 20x lens and adjust the focus. Adjust the position of the exterior body so that the joint part fits into a 4×6 area. (2) Specify the brightness of the area of the joint part and measure the area of the joint part. (3) Click the color extraction of "Area measurement" in "Measurement & Comment". Click on the joint part. (4) Click "Batch measurement", check "Display measurement result window", and save it in CSV data.

[0061] · "Elongation rate" means the value when the natural length is 100%. For example, an elongation rate of 200% is synonymous with an elongation magnification of 2 times.

[0062] · "Areal density" is measured as follows. After pre-drying the sample or test piece, leave it in a test chamber or device under standard conditions (test location: temperature 23 ± 1°C, relative humidity 50 ± 2%) until it reaches a constant weight. Pre-drying means making the sample or test piece reach a constant weight in an environment with a temperature of 100°C. For fibers with a moisture regain of 0.0%, pre-drying may not be necessary. From the test piece in a constant weight state, use a template for sample collection (100 mm × 100 mm) to cut out a sample with dimensions of 100 mm × 100 mm per square meter. Measure the weight of the sample, multiply it by 100, and calculate the weight per square meter as the areal density.

[0063] · "Thickness" is measured automatically using an automatic thickness measuring instrument (KES-G5 handy compression tester) under the conditions of load: 0.098 N / cm 2 , and pressurized area: 2 cm 2 .

[0064] · "Water absorption" is measured according to JIS K7223-1996 "Test method for water absorption of superabsorbent resins".

[0065] · "Water absorption rate" is defined as the "time to the end point" when performing JIS K7224-1996 "Test method for water absorption rate of superabsorbent resins" using 2 g of superabsorbent polymer and 50 g of physiological saline.

[0066] · If there is no description of the environmental conditions in the test or measurement, the test or measurement shall be carried out in a test chamber or device under standard conditions (test location: temperature 23 ± 1 °C, relative humidity 50 ± 2%).

[0067] · Unless otherwise specified, the dimensions of each part refer to the dimensions in the unfolded state rather than the natural length state.

Industrial Applicability

[0068] The present invention can be used for all disposable wearing articles of the pants type, such as pants-type disposable diapers, pants-type sanitary napkins, pants-type disposable diaper covers, etc., in addition to the pants-type disposable diapers as described in the above examples.

Explanation of Symbols

[0069] 10... Inner body, 11... Top sheet, 12... Liquid-impermeable sheet, 13... Gathered portion, 14... Wrapping sheet, 15... Three-dimensional gathered sheet, 16... Gathered elastic member, 18... Absorbent body, 20... Outer body, 20A... First sheet, 20B... Second sheet, 20C... Folded-back portion, 21... Side seal portion, 22, 23... Joint portion, 22... First joint portion, 23... Second joint portion, 24... Waist elastic member, 25... Lower waist elastic member, 26... Intermediate elastic member, 26a... First portion, 26b... Second portion, 27... Fixed portion, 29... Edge of leg opening, A1... Side non-stretch region, A2... Intermediate stretch region, A3... Edge region, B... Back body, BS... Three-dimensional gather, F... Front body, LD... Front-back direction, LO... Leg opening, M... Intermediate portion, T... Torso circumference portion, U... Lower waist portion, V... Width expansion portion, VC... Virtual circle, VL... Virtual line, W... Waist portion, WD... Width direction, WO... Waist opening, h1... First region, h2... Second region.

Claims

1. It has an annular body circumference part, an intermediate part that continues from the lower edge of the body circumference part at the front body to the crotch part and then to the lower edge of the body circumference part at the back body, leg openings formed on both sides of the intermediate part, and a waist opening formed above the body circumference part. Both side edges of the intermediate part form the edges of the leg openings. The intermediate part has a portion with the narrowest width at the crotch part, and has a widened part whose width gradually increases from there to the body circumference part at the front body and the body circumference part at the back body. In at least one of the widened parts of the front body and the back body, there is an elongated intermediate elastic member extending along the width direction, having a side non-stretchable region provided on both sides, an intermediate stretchable region adjacent to the central side in the width direction of the side non-stretchable region, a first portion located within the intermediate stretchable region and a second portion located within the side non-stretchable region; a first sheet extending over the side non-stretchable region and the intermediate stretchable region so as to cover the front side of the intermediate elastic member; a second sheet extending over the side non-stretchable region and the intermediate stretchable region so as to cover the back side of the intermediate elastic member; and a joining part where the first sheet and the second sheet are joined, provided at least at intervals in the front-rear direction. The intermediate stretchable region has a fixing part that fixes at least both ends of the first portion and at least one of the first sheet and the second sheet so as to stretch and contract in the width direction together with the intermediate elastic member. The second portion is not fixed to the first sheet and the second sheet and has contracted to its natural length. The side edge of the widened part has a shape passing through a position separated outside a virtual circle with a radius equal to the natural length of the second portion, centered on the boundary between the first portion and the second portion. The joining part is provided in an edge region between a virtual line parallel to the side edge of the widened part and separated by the shortest distance between the side edge of the widened part and the virtual circle. A disposable pant-type wearing article, characterized by the above.

2. The edge region has at least one joining part in a range from a direction of 15° on the body circumference part side to a direction of 90° on the opposite side when the side in the width direction is set to 0° when viewed from the center of the virtual circle. The disposable pant-type wearing article according to Claim 1.

3. A plurality of the intermediate elastic members are provided in the widened part at intervals in the front-rear direction. When the side in the width direction is defined as 0° when viewed from the center of the virtual circle in each intermediate elastic member, the edge region has one of the joining portions in each of the ranges from 0° to 15° in the direction of the body circumferential portion side and from 0° to 90° in the direction opposite to the body circumferential portion side. Among the intermediate elastic members adjacent to each other in the front-rear direction, when the side in the width direction is defined as 0° when viewed from the center of the virtual circle in the intermediate elastic member on the body circumferential portion side, the joining portion of the edge region located in the range from 0° to 90° in the direction opposite to the body circumferential portion side and the joining portion of the edge region located in the range from 0° to 15° in the direction of the body circumferential portion side when the side in the width direction is defined as 0° when viewed from the center of the virtual circle in the intermediate elastic member on the side opposite to the body circumferential portion side are the same joining portion. The pant-type disposable wearing article according to claim 2.

4. The joining portion includes a pair of first joining portions that are in close contact with both the front and rear sides of the first portion and a second joining portion located in the side non-elastic region. The pair of first joining portions are repeatedly provided at intervals in the width direction. The fixing portion is a cylindrical portion composed of the pair of first joining portions and the portion located between the pair of first joining portions among the first sheet and the second sheet. The second joining portion is repeatedly provided at intervals in the front-rear direction and the width direction within the side non-elastic region. The side non-elastic region has a first region that is in front of the virtual extension portion obtained by laterally extending the first portion along the width direction and has a radius equal to or less than the radius of the virtual circle, and a second region that is behind the virtual extension portion and has a radius equal to or less than the radius of the virtual circle. The second joining portion is provided in each of the first region and the second region. At least one of the second joining portion located in the first region and the second joining portion located in the second region is located in the edge region. The interval in the width direction between the pair of first joining portions located on the outermost side and the second joining portion adjacent to it on the side, and the interval between the second joining portions adjacent to each other in the width direction are equal and are equal to or less than the radius of the virtual circle. The pant-type disposable wearing article according to any one of claims 1 to 3.

5. The area of each of the second joining portions is the same as or smaller than the area of the first joining portion. The area ratio of the second joining portion in the side non-elastic region is smaller than the area ratio of the first joining portion in the intermediate elastic region. The pant-type disposable wearing article according to claim 4.

6. The side edges of the widening portion have a curved portion with the center of curvature located inside, spanning both the front and rear sides of a virtual extension portion obtained by extending at least one of the first portions laterally along the width direction. The pant-type disposable wearing article according to any one of claims 1 to 5.

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