JP7575251B2 - Pants-type disposable swimwear - Google Patents

Description

The present invention relates to a pants-type disposable swimsuit suitable for underwater use, such as playing in water or swimming.

In recent years, pants-type disposable swimwear (also called swimming pants) designed for use in swimming pools for infants and small children have become commercially available (see, for example, Patent Documents 1 and 2).

This type of pants-type disposable swimwear is designed to be worn either with a non-disposable cloth swimwear on top or without anything on the outside, and so differs from disposable diapers, which are worn over clothing on the outside.

In other words, disposable swimsuits are worn without any outerwear, or if there is, only as a swimsuit, so it goes without saying that the wearer's body temperature is likely to drop when they are used.

However, even though it is undesirable for infants and young children to get their abdomens cold, no disposable swimsuits have been provided to date that prevent the wearer's abdomen from getting cold. This is thought to be due to the natural perception that disposable swimsuits are equivalent to non-disposable cloth swimsuits, and as a result, no attention has been paid to their heat retention properties, etc.

JP 2005-296372 A JP 2005-537 A

Therefore, the main objective of the present invention is to improve the prevention of abdominal chills.

The pants-type disposable swimsuit that solves the above problems is as follows.
<First aspect>
A pants-type disposable swimsuit having a tubular waist region continuing in a waist direction, an intermediate region extending from a lower end of a front portion of the waist region through a crotch area to a lower end of a rear portion of the waist region, a waist opening, and a pair of left and right leg openings,
An exterior body that forms at least the waist area;
an inner body attached to the outer body so as to extend from a front portion of the waist region through the crotch area to a rear portion of the waist region;
An absorbent body incorporated in the inner body,
At least the front portion of the exterior body has a thermal insulation layer that is 60% or more of the waist area in the front-rear direction and extends across the entire width direction,
The heat-retaining layer is a nonwoven fabric containing hollow fibers.
A pants-type disposable swimsuit characterized by:

(Action and Effect)
In this way, by providing a heat-retaining layer made of a nonwoven fabric containing hollow fibers on at least the majority of the front part of the outer body of the pants-type disposable swimsuit, it is possible to improve the prevention of the wearer's abdomen from getting cold before entering the water (before the disposable swimsuit gets wet). Although infants use disposable swimsuits while swimming, they often only play with their toes in the water, and this pants-type disposable swimsuit is suitable for preventing the abdomen from getting cold in the latter use.

<Second aspect>
The heat-retaining layer is a spunbond nonwoven fabric having a basis weight of 10 to 20 g/m ² and a thickness of 0.1 to 0.3 mm, the basis weight being made of polyolefin hollow fibers having a fineness of 0.5 to 3.0 dtex and a hollow ratio of 10 to 40%.
The pants-type disposable swimsuit according to the first aspect.

(Action and Effect)
The nonwoven fabric containing hollow fibers is not particularly limited, but is preferably within the scope of this embodiment.

<Third aspect>
The waist portion of the outer cover has a plurality of elongated waist elastic members arranged in the width direction and spaced apart from one another, one or more inner waist layers located inside the waist elastic members, and one or more outer waist layers located outside the waist elastic members,
All of the waist inner layers and the waist elastic members are continuously joined to adjacent layers at least in the width direction;
the waist portion is capable of changing between an expanded state in which the waist inner layer and the waist outer layer have no shrinkage wrinkles and a natural length state in which the waist inner layer and the waist outer layer have shrinkage folds formed in the waist inner layer and the waist outer layer by shrinking in the width direction together with the waist elastic member,
The innermost layer of the waist inner layers is the heat retaining layer and forms a surface that contacts the wearer's skin.
A pants-type disposable swimsuit according to a second aspect.

(Action and Effect)
In a pants-type disposable swimsuit having a waist elastic member as in this embodiment, the inner surface of the waist portion having shrinkage wrinkles contacts the wearer's skin when worn. The presence of such shrinkage wrinkles makes it easy for a continuous gap to form in the front-rear direction between the inner surface of the waist portion and the skin. Although such a gap is preferable for improving breathability, it is not preferable in a disposable swimsuit because it may promote cooling of the abdomen and promote the ingress and egress of water after entering the water and the resulting leakage of excrement.
In contrast, when the inner waist layer which forms the skin-contacting surface of the waist portion is a thermal insulation layer of the second embodiment (i.e., a specific hollow fiber nonwoven fabric), it is more easily compressed than a solid fiber nonwoven fabric of the same degree, and the convex parts of the shrinkage wrinkles which form on the skin-contacting surface are lower (this phenomenon was not initially anticipated, and was discovered by chance while researching the use of thermal insulation layers), which improves the adhesion of the skin surface, improves prevention of abdominal chill, and suppresses the entry and exit of water after immersion and the resulting leakage of excrement.

<Fourth aspect>
At least the front portion of the exterior body has a cover layer on the inside of the thermal insulation layer, the cover layer having a front-to-rear dimension of 60% or more of the thermal insulation layer and extending across the entire width direction,
The cover layer forms a surface that contacts the wearer's skin,
the cover layer is a nonwoven fabric consisting of solid fibers,
The heat-retaining layer and the cover layer are both made of a hydrophobic nonwoven fabric or a water-repellent nonwoven fabric.
The pants-type disposable swimsuit according to any one of the first to third aspects.

(Action and Effect)
If only heat retention is taken into consideration, it is desirable to laminate as many heat-retaining layers as possible, but since nonwoven fabrics containing hollow fibers have higher water retention than nonwoven fabrics made only of solid fibers when compared at the same basis weight, if the surface in contact with the skin is made of a hollow fiber nonwoven fabric, the wet feeling tends to persist even after the disposable swimsuit is not in water after it gets wet, which may result in a decrease in heat retention and a worsening of the wearing comfort. In contrast, providing a cover layer made of a solid fiber nonwoven fabric as in this embodiment is preferable because it makes it difficult for the wet feeling to persist even after the disposable swimsuit gets wet.

The present invention offers the advantage of improving prevention of abdominal chills.

FIG. 2 is a plan view showing the inner surface of the pants-type disposable swimsuit in an open state. FIG. 2 is a plan view showing the outer surface of the pants-type disposable swimsuit in an open state. This is a cross-sectional view of FIG. This is a cross-sectional view of FIG. 1 along line 3-3. 1A is a cross-sectional view taken along line 4-4 of FIG. 1, and FIG. FIG. 1 is a perspective view of a pants-type disposable swimsuit. This is a plan view showing only the essential parts of the outer surface of the pants-type disposable swimsuit in an open state. 7A is a cross-sectional view taken along line 4-4 of FIG. 7, and FIG. 7B is a cross-sectional view taken along line 5-5 of FIG. 1A is a cross-sectional view taken along line 4-4 of FIG. 1, and FIG. FIG. 4 is a cross-sectional view showing a main part of the waist portion. FIG. 1 is a schematic diagram showing a procedure for a thermal conductivity test. 1 is a graph showing the results of a thermal conductivity test.

An example of a pants-type disposable swimsuit will be described in detail below with reference to the attached drawings. Each component adjacent in the thickness direction is fixed or joined as necessary in the same manner as known diapers, except for the fixed or joined parts described below. The dotted pattern in the cross-sectional view indicates an adhesive such as a hot melt adhesive as the fixing or joining means. The hot melt adhesive can be applied by known methods such as slot application, continuous line or dotted line bead application, spiral, Z-shaped, wavy, etc. spray application, or pattern coating (transfer of hot melt adhesive by letterpress method). Alternatively or in addition to this, at the fixing part of the elastic member, the hot melt adhesive can be applied to the outer circumferential surface of the elastic member to fix the elastic member to the adjacent member. As the hot melt adhesive, for example, EVA-based, adhesive rubber-based (elastomer-based), polyolefin- based, polyester-polyamide-based, and other types are available, but they can be used without any particular limitation. As a fixing or joining means for joining each component, a material welding means such as heat sealing or ultrasonic sealing can also be used. In a portion where liquid permeability in the thickness direction is required, adjacent components in the thickness direction are fixed or joined in an intermittent pattern. For example, when such intermittent fixing or joining is performed with a hot melt adhesive, intermittent pattern coating in a spiral, Z-shape, wave shape, etc. can be suitably used, and when coating an area greater than the coating width of one nozzle, intermittent pattern coating in a spiral, Z-shape, wave shape, etc. can be performed with or without gaps in the width direction. As a joining means for joining each component, material welding means such as heat sealing and ultrasonic sealing can also be used.

In addition, as the nonwoven fabric in the following description, known nonwoven fabrics can be appropriately used depending on the part and purpose. The constituent fibers of the nonwoven fabric can be selected without particular limitation, for example, synthetic fibers such as polyolefins such as polyethylene or polypropylene, polyesters, polyamides, etc. (including single-component fibers and composite fibers such as core-sheath fibers), regenerated fibers such as rayon and cupra, natural fibers such as cotton, etc., and these can also be used in combination. In order to increase the flexibility of the nonwoven fabric, it is preferable to use crimped fibers as the constituent fibers. In addition, the constituent fibers of the nonwoven fabric may be hydrophilic fibers (including fibers that have been made hydrophilic by a hydrophilizing agent), hydrophobic fibers, or water-repellent fibers (including fibers that have been made water-repellent by a water-repellent agent). Furthermore, nonwoven fabrics are generally classified into staple fiber nonwoven fabrics, long fiber nonwoven fabrics, spunbond nonwoven fabrics, meltblown nonwoven fabrics, spunlace nonwoven fabrics, thermal bond (air-through) nonwoven fabrics, needle punched nonwoven fabrics, point bond nonwoven fabrics, laminated nonwoven fabrics (SMS nonwoven fabrics, SMMS nonwoven fabrics, etc. in which a meltblown layer is sandwiched between spunbond layers), etc., depending on the fiber length, sheet formation method, fiber bonding method, and laminated structure, and any of these nonwoven fabrics can be used.

1 to 6 show an example of a pants-type disposable swimsuit. This pants-type disposable swimsuit comprises a rectangular front exterior body 12F constituting at least the waist region T of the front body F, a rectangular rear exterior body 12B constituting at least the waist region T of the back body B, and an inner body 200 attached to the exterior bodies 12F, 12B so as to extend from the front exterior body 12F through the crotch region to the rear exterior body 12B. Both sides of the front exterior body 12F and both sides of the rear exterior body 12B are joined to form side seal parts 12A, and an opening formed by the front and rear ends of the exterior bodies 12F, 12B becomes a waist opening WO through which the torso of the wearer passes, and the parts on both sides of the inner body 200 in the width direction surrounded by the lower edges of the exterior bodies 12F, 12B and the side edges of the inner body 200 become leg openings LO through which the legs pass. The inner body 200 is a part that absorbs and retains excrement such as urine, and the outer bodies 12F and 12B are parts that support the inner body 200 against the wearer's body. Also, the symbol Y indicates the overall length of the swimsuit in the unfolded state (the length in the front-to-rear direction from the edge of the waist opening WO of the front body F to the edge of the waist opening WO of the back body B), and the symbol X indicates the overall width of the swimsuit in the unfolded state.

In this pants-type disposable swimsuit, the cylindrical waist region T, which is continuous in the waist direction, is defined as the front-rear range having the side seal portion 12A (the front-rear range from the waist opening WO to the upper end of the leg opening LO). The middle region L, which extends from the lower end of the front part of the waist region through the crotch area to the lower end of the rear part of the waist region, is defined as the front-rear range of the part that forms the leg opening LO (between the front-rear region having the side seal portion 12A of the front body F and the front-rear region having the side seal portion 12A of the rear body B). The waist region T can be conceptually divided into a "waist portion" W that forms the edge of the waist opening and a "lower waist portion" U that is the portion below this. Usually, when there is a boundary in the waist region T where the stretch stress in the width direction WD changes (for example, the thickness or elongation rate of the elastic member changes), the waist section W is the part closer to the waist opening WO than the boundary closest to the waist opening WO, and when there is no such boundary, the part extending further toward the waist opening WO than the absorbent body 56 or the inner body 200 is the waist section W. The length of these in the front-rear direction varies depending on the size of the product and can be determined appropriately, but as an example, the waist section W can be 15 to 40 mm, and the lower waist section U can be 65 to 120 mm. On the other hand, both side edges of the middle region L are narrowed in a U-shape or curved shape to fit around the legs of the wearer, and these are the parts where the wearer's legs are inserted. As a result, the pants-type disposable swimsuit in the opened state has a roughly hourglass shape as a whole.

(Interior body)
The inner body 200 may have any shape, but is rectangular in the illustrated form. As shown in Figures 3 to 5, the inner body 200 comprises a top sheet 30 that contacts the wearer's skin, a liquid-impermeable sheet 11, and an absorbent element 50 interposed therebetween. Reference numeral 40 denotes an intermediate sheet (second sheet) provided between the top sheet 30 and the absorbent element 50 in order to quickly transfer liquid that has permeated the top sheet 30 to the absorbent element 50, and reference numeral 60 denotes rising gathers 60 that extend from both sides of the inner body 200 so as to contact the wearer's skin in order to prevent excrement from leaking to both sides of the inner body 200.

(Top sheet)
The top sheet 30 has a property of being permeable to liquid, and examples of the top sheet 30 include a perforated or non-perforated nonwoven fabric, a perforated plastic sheet, etc. Both side portions of the top sheet 30 may be folded back to the back side at the side edges of the absorbent element 50, or may not be folded back and may extend beyond the side edges of the absorbent element 50.

To prevent the top sheet 30 from being misaligned with respect to the backing material, it is desirable to fix the top sheet 30 to the backing material by a joining means such as heat sealing or ultrasonic sealing, or by a hot melt adhesive. In the illustrated example, the top sheet 30 is fixed to the surface of the intermediate sheet 40 and the surface of the portion of the packaging sheet 58 that is located on the front side of the absorbent body 56 by a hot melt adhesive applied to the back side of the top sheet 30.

(middle seat)
The intermediate sheet 40 is joined to the back surface of the top sheet 30 in order to quickly move excreted liquid that has passed through the top sheet 30 to the absorbent body 70 and to prevent backflow. The intermediate sheet 40 and the top sheet 30 can be joined together using a hot melt adhesive, heat embossing or ultrasonic welding.

As the intermediate sheet 40, in addition to using a nonwoven fabric, a resin film having a large number of through holes can also be used. The same material as that of the top sheet 30 can be used as the nonwoven fabric, but a material having a higher hydrophilicity than the top sheet 30 or a higher fiber density is preferable because it has excellent liquid transfer characteristics from the top sheet 30 to the intermediate sheet 40. For example, an air-through nonwoven fabric can be suitably used as the intermediate sheet 40. For the air-through nonwoven fabric, it is preferable to use composite fibers with a core-sheath structure, and in this case, the resin used for the core may be polypropylene (PP), but polyester (PET) with high rigidity is preferable. The basis weight is preferably 17 to 80 g/m ² , and more preferably 25 to 60 g/m ^2. The thickness of the raw fiber of the nonwoven fabric is preferably 2.0 to 10 dtex. In order to make the nonwoven fabric bulky, it is also preferable to use eccentric fibers with no core in the center, hollow fibers, or eccentric and hollow fibers as the mixed fibers of all or part of the raw fiber.

In the illustrated example, the intermediate sheet 40 is positioned in the center and is shorter than the width of the absorbent body 56, but it may be provided across the entire width. The length of the intermediate sheet 40 in the front-to-rear direction may be the same as the length of the inner body 200 or the absorbent element 50, or may be within a short length range centered on the area that receives liquid.

The intermediate sheet 40 is preferably fixed to the adjacent backside member by a material welding joining means such as heat sealing or ultrasonic sealing, or by a hot melt adhesive, in order to prevent misalignment relative to the backside member. In the illustrated example, the intermediate sheet 40 is fixed to the surface of the portion of the packaging sheet 58 that is located on the front side of the absorbent body 56 by a hot melt adhesive applied to the backside.

(Liquid-impermeable sheet)
The material of the liquid-impermeable sheet 11 is not particularly limited, but examples thereof include plastic films made of polyolefin resins such as polyethylene and polypropylene, laminated nonwoven fabrics in which a plastic film is provided on the surface of a nonwoven fabric, and laminated sheets in which a nonwoven fabric is laminated and bonded to a plastic film. For the liquid-impermeable sheet 11, it is preferable to use a material that is liquid-impermeable and moisture-permeable, which is preferred from the viewpoint of preventing stuffiness. As a moisture-permeable plastic film, a microporous plastic film obtained by kneading an inorganic filler into a polyolefin resin such as polyethylene or polypropylene to form a sheet and then stretching it in a uniaxial or biaxial direction is widely used. In addition, a sheet that has been made liquid-impermeable without using a plastic film by a method such as a nonwoven fabric using microdenier fibers, a method of strengthening leakproofness by applying heat or pressure to reduce the voids in the fibers, or a method of coating with a highly water-absorbent resin or a hydrophobic resin or a water-repellent agent can also be used as the liquid-impermeable sheet 11.

The liquid-impermeable sheet 11 is made to a width that fits behind the absorbent element 50 as shown in the figure, but in order to improve leak-proofing, it can also be made to wrap around both sides of the absorbent element 50 and extend to both sides of the top sheet 30 side of the absorbent element 50.

(Rising gather)
The rising gathers 60 extend along both sides of the inner body 200 throughout the front-to-rear direction LD and are provided to come into contact with the wearer's skin to prevent side leakage, and include what are generally called three-dimensional gathers.

The rising gathers 60 shown in Figures 1, 3, and 4 are so-called three-dimensional gathers, which rise from the side of the inner body 200 to the front side. The root side portion 60B of these rising gathers 60 rises diagonally toward the center in the width direction, and the tip side portion 60A from the middle portion rises diagonally toward the outside in the width direction, but this is not limited to this and appropriate modifications are possible, such as a form in which the gathers rise overall toward the center in the width direction.

Explaining in more detail, the rising gathers 60 in the illustrated example are formed by folding back a strip-shaped gathered nonwoven fabric 62 having a length equal to the front-rear length of the inner body 200 in the width direction WD at its tip and folding it in two, and fixing a plurality of elongated gathered elastic members 63 at intervals in the width direction WD between the folded-back portion and the sheet in the vicinity of the folded-back portion. The base end portion of the rising gathers 60 located opposite the tip portion (the end portion opposite the folded-back portion of the sheet in the width direction WD) is a root portion 65 fixed to the side portion on the back side of the liquid-impermeable sheet 11 of the inner body 200, and the portion other than the root portion 65 is a main portion 66 (portion on the folded-back portion side) extending from the root portion 65. The main body portion 66 has a root side portion 60B extending toward the center in the width direction, and a tip side portion 60A that is folded back at the tip of the root side portion 60B and extends outward in the width direction. This form is a surface contact type of risen gather 60, but a line contact type of risen gather 60 that is not folded back outward in the width direction can also be used. The front-rear direction ends of the main body portion 66 are formed as fallen portions 67 that are fixed in a fallen state to the side surfaces of the top sheet 30, while the front-rear direction intermediate portion between them is formed as a non-fixed free portion 68, and a gather elastic member 63 that extends along the front-rear direction LD is fixed in a stretched state to at least the tip of this free portion 68.

In the rise-up gathers 60 configured as described above, the contractile force of the gather elastic member 63 acts to bring the front-rear end closer together, but while the front-rear end of the main body portion 66 is fixed so that it does not stand up, the area between them is an unfixed free portion 68, so that only the free portion 68 stands up so as to abut against the body side as shown by the arrow in Figure 3. In particular, when the root portion 65 is located on the back side of the inner body 200, the free portion 68 stands up so as to open outward in the width direction in the crotch area and its vicinity, so that the rise-up gathers 60 come into contact with the leg circumference with a surface, improving the fit.

In the illustrated example of the rising gather 60, in a bent form in which the main body portion 66 is made up of a root side portion 60B extending toward the center in the width direction and a tip side portion 60A folded back at the tip of the root side portion 60B and extending outward in the width direction, the tip side portion 60A and the root side portion 60B are joined in a fallen state at the fallen portion 67, and the root side portion 60B is joined in a fallen state to the top sheet 30. At least one of various hot melt adhesives applied by various methods and material welding means such as heat sealing and ultrasonic sealing can be used to join the opposing surfaces at the fallen portion 67. In this case, the joining of the root side portion 60B and the top sheet 30 and the joining of the tip side portion 60A and the root side portion 60B may be performed by the same means or by different means. For example, one preferred embodiment is to bond the base portion 60B to the top sheet 30 with a hot melt adhesive, and to bond the tip portion 60A to the base portion 60B by material welding.

As the gathered nonwoven fabric 62, a nonwoven fabric that is soft and has excellent uniformity and hiding properties, such as a spunbond nonwoven fabric (SS, SSS, etc.), an SMS nonwoven fabric (SMS, SSMMS, etc.), or a meltblown nonwoven fabric, which is treated with a water repellent treatment using silicone or the like as necessary, can be suitably used, and the fiber basis weight is preferably about 10 to 30 g/m2. As the gathered elastic member 63, a rubber thread or the like can be used. When a spandex rubber thread is used, the thickness is preferably 470 to 1240 dtex, and ^more preferably 620 to 940 dtex. The elongation rate at the time of fixing is preferably 150 to 350%, and more preferably 200 to 300%. Also, as shown in the figure, a waterproof film 64 can be interposed between the gathered nonwoven fabric 62 folded in two, in which case the gathered nonwoven fabric 62 can be partially omitted where the waterproof film 64 is present; however, in order to make the product look and feel like cloth, it is necessary that at least the outer surface from the base end to the tip of the rising gathers 60 be formed of gathered nonwoven fabric 62, as in the example shown.

The number of gather elastic members 63 provided in the free portion of the rising gathers 60 is preferably 2 to 6, and more preferably 3 to 5. The appropriate placement interval 60d is 3 to 10 mm. With this configuration, the gather elastic members 63 can easily come into contact with the skin in the area in which they are placed. The gather elastic members 63 may be placed not only on the tip side but also on the base side.

In the free portion 68 of the rising gather 60, at least one of various application methods of hot melt adhesive and material welding such as heat sealing and ultrasonic sealing can be used to bond the inner layer and outer layer of the gathered nonwoven fabric 62 together and to fix the gathered elastic member 63 sandwiched between them. If the entire surfaces of the inner layer and outer layer of the gathered nonwoven fabric 62 are bonded together, flexibility is lost, so it is preferable that the parts other than the adhesive part of the gathered elastic member 63 are not bonded or are weakly bonded. In the illustrated example, hot melt adhesive is applied only to the outer peripheral surface of the gathered elastic member 63 by an application means such as a comb gun or a surwrap nozzle, and the gathered nonwoven fabric 62 is sandwiched between the inner layer and the outer layer, so that the gathered elastic member 63 is fixed to the inner layer and the outer layer of the gathered nonwoven fabric 62 and the inner layer and the outer layer of the gathered nonwoven fabric 62 are fixed only by the hot melt adhesive applied to the outer peripheral surface of the gathered elastic member 63.

Similarly, the waterproof film 64 incorporated in the rising gathers 60 can be fixed to the gathered nonwoven fabric 62, and the fallen portion 67 can be fixed using at least one of a variety of hot melt adhesives applied by various methods and material welding methods such as heat sealing and ultrasonic sealing.

The dimensions of the rising gathers 60 in the illustrated example can be determined as appropriate, but in the case of disposable swimsuits for infants and toddlers, for example as shown in Figure 3, the rising height W2 of the rising gathers 60 (the widthwise length of the main body portion 66 in the unfolded state) is preferably 15 to 60 mm, and particularly 20 to 40 mm. In addition, when the rising gathers 60 are folded flat so as to be parallel to the surface of the top sheet 30, the distance W1 between the innermost folds is preferably 60 to 190 mm, and particularly 70 to 140 mm.

(Absorption element)
The absorbent element 50 has an absorbent body 56 and a wrapping sheet 58 that wraps the entire absorbent body 56. The wrapping sheet 58 may be omitted.

(Absorbent)
The absorbent body 56 can be formed by a fiber assembly. As the fiber assembly, in addition to stacked staple fibers such as cotton-like pulp and synthetic fibers, a filament assembly obtained by opening a tow (fiber bundle) of synthetic fibers such as cellulose acetate as necessary can be used. The fiber basis weight can be, for example, about 100 to 300 g/m ² when stacking cotton-like pulp or staple fibers, and can be, for example, about 30 to 120 g/m ² when the filament assembly is used. The fineness of the synthetic fibers is, for example, 1 to 16 dtex, preferably 1 to 10 dtex, and more preferably 1 to 5 dtex. In the case of a filament assembly, the filaments may be non-crimped fibers, but are preferably crimped fibers. The crimp degree of the crimped fibers can be, for example, about 5 to 75, preferably 10 to 50, and more preferably 15 to 50, per 2.54 cm. Also, uniformly crimped fibers can be used. It is preferable that highly absorbent polymer particles are dispersed and held within the absorbent body 56.

The absorbent body 56 may be rectangular in shape, but as shown in FIG. 8 and other figures, it is preferable to have an hourglass shape with a narrower constricted portion 56N in the middle in the front-to-rear direction than the front and rear ends, as this improves the fit of the absorbent body 56 itself and the rising gathers 60 around the legs.

The dimensions of the absorbent body 56 can be determined as appropriate as long as they extend in all directions from the urination opening position, but it is preferable that the absorbent body 56 extend to the periphery of the inner body 200 or its vicinity in the front-to-back direction LD and width direction WD. The symbol 56X indicates the overall width of the absorbent body 56.

(Superabsorbent polymer particles)
The absorbent body 56 desirably does not contain a superabsorbent polymer, but may contain one. The superabsorbent polymer particles include not only "particles" but also "powder". The superabsorbent polymer particles used in this type of disposable swimsuit can be used as is, and for example, the percentage of particles remaining on a sieve using a 500 μm standard sieve (JIS Z8801-1:2006) after sieving (shaking for 5 minutes) is desirably 30% by weight or less, and the percentage of particles remaining on a sieve using a 180 μm standard sieve (JIS Z8801-1:2006) after sieving (shaking for 5 minutes) is desirably 60% by weight or more.

There are no particular limitations on the material that can be used for the superabsorbent polymer particles, but those with a water absorption capacity of 40 g/g or more are preferred. Superabsorbent polymer particles include starch-based, cellulose-based and synthetic polymer-based materials, and examples of materials that can be used include starch-acrylic acid (salt) graft copolymers, saponified starch-acrylonitrile copolymers, crosslinked products of sodium carboxymethylcellulose and acrylic acid (salt) polymers. The shape of the superabsorbent polymer particles is preferably the commonly used powder-like form, but other shapes can also be used.

The highly absorbent polymer particles preferably have a water absorption speed of 70 seconds or less, and particularly 40 seconds or less. If the water absorption speed is too slow, the liquid supplied to the absorbent body 56 tends to flow back out of the absorbent body 56, which is known as backflow.

The highly absorbent polymer particles preferably have a gel strength of 1000 Pa or more. This effectively prevents the sticky feeling after absorbing liquid, even when the absorbent body 56 is bulky.

(packaging sheet)
When the wrapping sheet 58 is used, the material may be tissue paper, particularly crepe paper, nonwoven fabric, polylaminated nonwoven fabric, a sheet with small holes, or the like. However, it is preferable that the sheet is one from which the superabsorbent polymer particles do not escape. When using nonwoven fabric instead of crepe paper, hydrophilic SMS nonwoven fabric (SMS, SSMMS, etc.) is particularly suitable, and the material may be polypropylene, a polyethylene/polypropylene composite, or the like. The basis weight is preferably 5 to 40 g/ ^m2 , particularly 10 to 30 g/ ^m2 .

The packaging form of the packaging sheet 58 can be determined as appropriate, but from the standpoint of ease of manufacture and prevention of leakage of superabsorbent polymer particles from the front and rear edges, it is preferable to wrap the sheet around the front and rear surfaces and both sides of the absorbent 56 in a cylindrical shape, with the front and rear edges extending beyond the front and rear of the absorbent 56, and to join the overlapping parts of the wrap and the overlapping parts of the protruding front and rear edges with a joining means such as a hot melt adhesive or material welding.

(Exterior body)
The exterior bodies 12F, 12B in the illustrated example are composed of a rectangular front exterior body 12F which is a portion constituting at least the waist region T of the front body F, and a rectangular rear exterior body 12B which is a portion constituting at least the waist region T of the back body B, and the front exterior body 12F and the rear exterior body 12B are not continuous on the crotch side, but are separated in the front-to-rear direction LD. This separation distance 12d can be, for example, about 150 to 250 mm. Also, as shown in Figures 7 and 8, the exterior body 12 may be continuous from the front body F to the back body B through the crotch. In this case, the exterior body forms the waist region and the middle region.

In the illustrated example, the rear exterior body 12B has a longer front-to-rear dimension than the front exterior body 12F, and the front exterior body 12F does not have a portion corresponding to the middle region L, but the rear exterior body 12B has a buttocks cover portion C extending from the waist region T toward the middle region L. Although not illustrated, the front exterior body 12F may also be provided with a groin cover portion extending from the waist region T toward the middle region L. Also, although not illustrated, both the front exterior body 12F and the rear exterior body 12B may not have a portion extending from the waist region T toward the middle region L (the front-to-rear dimensions of the front exterior body 12F, the rear exterior body 12B, and the side seal portion may all be the same).

When the buttocks cover portion C is provided, the length of the rear exterior body 12B in the front-to-rear direction LD can be determined as appropriate, but can be, for example, 1.1 to 1.5 times the length of the side seal portion 12A in the front-to-rear direction LD.

As shown in Figures 4 and 5, the exterior bodies 12F, 12B are formed by joining an outer sheet layer and an inner sheet layer adjacent to the outer side and the inner side of the elastic members 15-19 described later, respectively, by a joining means such as a hot melt adhesive or welding. The outer sheet layer and the inner sheet layer may be formed of two sheets 12S, 12H as in the example shown in Figure 5 and the example shown in Figure 8, or may be formed of a single sheet material 12S as shown in Figure 9. That is, in the latter case, the inner sheet layer and the outer sheet layer are respectively formed of the inner part and the outer part of a single sheet material 12S folded back at the edge of the waist opening WO (which may be the edge on the crotch side) in part or all of the exterior bodies 12F, 12B. 5 is a combination of the former and latter, in which the sheet material 12H forming the inner sheet layer extends only to the lower end of the waist portion, but the sheet material 12S forming the outer sheet layer wraps around the waist opening WO side of the sheet material 12H of the inner sheet layer and folds back inward, and this folded back portion 12r extends so as to cover up to the end of the waist opening WO side of the inner body 200. In this case, in most of the waist portion W, the sheet material forming the outer sheet layer and the sheet material forming the inner sheet layer are a single sheet material 12S, and in other parts, they are separate sheet materials 12S, 12H. On the other hand, the example shown in Figure 8 corresponds to the former, in which the sheet material 12H forming the inner sheet layer extends only to the edge of the waist opening WO, but the sheet material 12S forming the outer sheet layer goes around the edge of the sheet material 12H of the inner sheet layer on the waist opening WO side and is folded back inward, and this folded back portion 12r extends so as to cover the end of the inner body 200 on the waist opening WO side.

The sheet materials 12S, 12H used for the outer sheet layer and the inner sheet layer can be used without any particular limitation, but nonwoven fabric is preferable. When nonwoven fabric is used, the fiber weight is preferably about 10 to 30 g/m ² .

(Stretchable area/non-stretchable area)
In order to improve the fit around the waist of the wearer, the exterior bodies 12F and 12B are provided with elastic members 15 to 19 between the outer sheet layer and the inner sheet layer. The elastic region A2 is formed to elastically expand and contract in the direction WD. In the elastic region A2, the outer sheet layer, the inner sheet layer, and the sheet layers joined thereto are in a natural length state due to the contraction of the elastic members 15 to 19. When the elastic members 15 to 19 are stretched in the longitudinal direction, the outer sheet layer, the inner sheet layer, and the sheet layers joined thereto are stretched to a predetermined length without wrinkles. The elastic members 15 to 19 may be any known elastic member, such as a thin elastic member (illustrated example) such as rubber thread, a strip, a net, a film, or the like, without any particular limitation. The elastic members 15 to 19 may be made of synthetic rubber or natural rubber.

In the exterior bodies 12F, 12B, the adjacent sheet layers in the thickness direction are bonded together, and the elastic members 15-19 sandwiched between them can be fixed using at least one of a variety of hot melt adhesives applied by various methods and material welding fixing means such as heat sealing and ultrasonic sealing. For example, the elastic members 15-19 may be fixed to the outer sheet layer and the inner sheet layer only at both ends in the stretch direction in the stretch region, or hot melt adhesive may be applied only to the parts through which the elastic members 15-19 pass, to fix the elastic members 15-19 to the outer sheet layer and the inner sheet layer, and to fix the elastic members 15-19 between the outer sheet layer and the inner sheet layer. However, in the case of disposable swimsuits, it is desirable to maintain sufficient strength even after immersion in water, so it is preferable to apply hot melt adhesive in a planar or spiral pattern to one of the opposing surfaces of the outer sheet layer and the inner sheet layer, and also apply hot melt adhesive to the outer peripheral surfaces of the elastic members 15-19 using an application means such as a comb gun or a SureWrap nozzle, and then sandwich them between the outer sheet layer and the inner sheet layer to fix the elastic members 15-19 to the outer sheet layer and the inner sheet layer, and to join the outer sheet layer and the inner sheet layer.

To explain the elastic members 15-19 in the illustrated example in more detail, a plurality of waist elastic members 17 are attached at intervals in the front-rear direction between the outer sheet layer and the inner sheet layer in the waist portion W of the outer bodies 12F, 12B so as to be continuous throughout the entire width direction WD. Furthermore, of the waist elastic members 17, one or more arranged in the region adjacent to the waist lower portion U may overlap the inner body 200, or may be provided on both sides in the width direction except for the width direction central portion that overlaps with the inner body 200. The waist elastic member 17 is preferably made of 3 to 22 rubber threads having a thickness of 155 to 1880 dtex, particularly about 470 to 1240 dtex (in the case of synthetic rubber; in the case of natural rubber, a cross-sectional area of 0.05 to 1.5 ^mm2 , particularly about 0.1 to 1.0 ^mm2 ) spaced at intervals of 4 to 12 mm, and the resulting elongation rate in the width direction WD of the waist portion W is preferably about 150 to 400%, particularly about 220 to 320%. Furthermore, it is not necessary for the waist portion W to use waist elastic members 17 of the same thickness or to have the same elongation rate in all of its front-to-back directions LD; for example, the thickness or elongation rate of the elastic members 17 may be different in the upper and lower parts of the waist portion W.

In addition, multiple waist lower elastic members 15, 19 made of elongated elastic members are attached at intervals in the front-to-rear direction between the outer sheet layer and the inner sheet layer in the waist lower portion U of the exterior bodies 12F, 12B.

The lower waist elastic members 15, 19 are preferably made of about 5 to 30 rubber threads having a thickness of 155 to 1880 dtex, especially 470 to 1240 dtex (in the case of synthetic rubber; in the case of natural rubber, a cross-sectional area of 0.05 to 1.5 ^mm2 , especially 0.1 to 1.0 ^mm2 ) spaced at intervals of 1 to 15 mm, especially 3 to 8 mm, and the resulting elongation rate in the width direction WD of the lower waist portion U is preferably 200 to 350%, especially 240 to 300%.

In addition, a cover elastic member 16 made of an elongated elastic member is attached between the outer sheet layer and the inner sheet layer in the buttocks cover portion C of the rear exterior body 12B. The buttocks cover portion C is contracted toward the center in the width direction WD by the cover elastic member 16.

The cover elastic member 16 is preferably a rubber thread having a thickness of 155 to 1880 dtex, particularly about 470 to 1240 dtex (in the case of synthetic rubber; in the case of natural rubber, a cross-sectional area of 0.05 to 1.5 ^mm2 , particularly about 0.1 to 1.0 ^mm2 ), and the resulting elongation rate in the width direction WD of the buttocks cover portion C is preferably 150 to 400%, particularly preferably 250 to 350%. The number of cover elastic members 16 can be determined as appropriate, but 3 to 10 pieces are preferable, and 3 to 5 pieces are more preferable.

On the other hand, if a groin cover portion is provided on the front exterior body 12F, a cover portion elastic member can be provided in the same manner as the buttocks cover portion C.

When elastic members 15, 16, 19 are provided in the front-rear range including the absorbent body 56, as in the lower waist portion U and buttocks cover portion C in the illustrated example, in order to prevent contraction of the absorbent body 56 in the width direction WD in part or all of it, the middle in the width direction including part or all of the part overlapping with the absorbent body 56 in the width direction WD (preferably including the entire inner and outer joints 201, 202) is made into a non-stretchable region A1, and both sides in the width direction are made into stretchable regions A2. It is preferable that the waist portion W is made into a stretchable region A2 over the entire width direction WD, but a non-stretchable region A1 may be provided in the middle in the width direction, as in the lower waist portion U.

Such stretchable regions A2 and non-stretchable regions A1 can be constructed by supplying elastic members 15-17, 19 between the inner sheet layer and the outer sheet layer, fixing the elastic members 15, 16, 19 with hot melt adhesive at least at both ends in the stretch direction in the stretchable region A2 but not fixing them in the region that will become the non-stretchable region A1, and cutting the elastic members 15, 16, 19 in the region that will become the non-stretchable region A1 at one location in the middle of the width direction by applying pressure and heat or by cutting them finely in multiple locations, thereby retaining stretchability in the stretchable region A2 while eliminating stretchability in the non-stretchable region A1. In the former case, as shown in FIG. 4, in the non-stretchable region A1, the cut-off remnants continuing from the elastic members 15, 16, 19 of the stretchable region A2 remain between the outer sheet layer and the inner sheet layer in a state in which they have shrunk to their natural length as unnecessary elastic members 18 alone; in the latter case, although not shown, the cut-off remnants continuing from the elastic members 15, 16, 19 of the stretchable region A2 and cut pieces of the elastic members not continuing from the elastic members 15, 16, 19 of both stretchable regions A2 remain between the outer sheet layer and the inner sheet layer in a state in which they have shrunk to their natural length alone as unnecessary elastic members.

(Nonwoven cover)
In a pants-type disposable swimsuit with a two-piece exterior, the interior body 200 is exposed between the front exterior body 12F and the rear exterior body 12B, so it is preferable to have a cover nonwoven fabric 13 that covers the back surface of the interior body 200 from between the front exterior body 12F and the interior body 200 to between the rear exterior body 12B and the interior body 200 so that the liquid-impermeable sheet 11 is not exposed on the back surface of the interior body 200.

The nonwoven fabric used for the cover nonwoven fabric 13 can be appropriately selected from a material similar to that of the exterior bodies 12F and 12B, for example.

The front-rear range of the cover nonwoven fabric 13 is not particularly limited, and may extend in the front-rear direction LD over the entire area from the front end to the rear end of the inner body 200 as shown in Figs. 2 and 5, or may extend in the front-rear direction LD from the front-rear middle position of the area where the front outer body 12F and the inner body 200 overlap to the front-rear middle position of the area where the rear outer body 12B and the inner body 200 overlap as shown in Fig. 8. In the example shown in Fig. 8, the front-rear length 13y of the overlapping portion between the cover nonwoven fabric 13 and the front outer body 12F and the front-rear length 13y of the overlapping portion between the cover nonwoven fabric 13 and the rear outer body 12B can be determined as appropriate, but usually can be about 20 to 40 mm each.

The width direction range of the cover nonwoven fabric 13 is set to a range that can hide the exposed back surface of the liquid-impermeable sheet 11. For this reason, in the illustrated example, since the liquid-impermeable sheet 11 is exposed between the base ends of the left and right rising gathers 60, the cover nonwoven fabric 13 is provided so as to cover at least the width direction range from the back side of the base end of one rising gather 60 to the back side of the base end of the other rising gather 60. This allows the liquid-impermeable sheet 11 to be concealed by the cover nonwoven fabric 13 and the gathered nonwoven fabric 62 of the rising gathers 60. In addition, even if the width direction ends of the cover nonwoven fabric 13 do not cover the back side of the base end of the rising gathers 60, but the gathered nonwoven fabric 62 covers the back side of the width direction ends of the cover nonwoven fabric 13, it is possible to conceal the liquid-impermeable sheet 11 by the cover nonwoven fabric 13 and the gathered nonwoven fabric 62. In this case, since both sides of the cover nonwoven fabric 13 are covered with the gathered nonwoven fabric 62, there is an advantage that both sides of the cover nonwoven fabric 13 are less likely to peel off from the liquid-impermeable sheet 11.

The inner and outer surfaces of the cover nonwoven fabric 13 can be bonded to the opposing surfaces via a hot melt adhesive. The fixed area of the cover nonwoven fabric 13 can be the entire front-to-rear and width direction of the cover nonwoven fabric 13, or a portion can be left unfixed. For example, if both ends in the width direction of the cover nonwoven fabric 13 are unfixed, the cover nonwoven fabric 13 is less susceptible to the influence of the rising gathers 60 even if the sides of the absorbent body 56 shrink somewhat, which has the advantage that wrinkles and folds are less likely to form in the cover nonwoven fabric 13. In this case, the width of the unfixed portions of both ends in the width direction of the cover nonwoven fabric 13 can be set as appropriate, but can be, for example, 3 to 10 mm, preferably 5 to 8 mm.

(Inner and outer joints)
The inner body 200 can be fixed to the outer bodies 12F, 12B by a joining means using material welding such as heat sealing or ultrasonic sealing, or by a hot melt adhesive. In the illustrated example, the inner body 200 is fixed to the inner surface of the outer bodies 12F, 12B via a hot melt adhesive applied to the back surface of the inner body 200, that is, in this case, the back surface of the liquid-impermeable sheet 11 and the root portion 65 of the rising gathers 60. The inner and outer joining portions 201, 202 that fix the inner body 200 and the outer bodies 12F, 12B can be provided in almost the entire overlapping area as shown in FIG. 2, and can also be provided in a portion excluding both ends in the width direction of the inner body 200, for example.

(Thermal insulation layer)
The exterior bodies 12F, 12B have a heat-retaining layer IL made of a nonwoven fabric containing hollow fibers, and it is preferable that this heat-retaining layer IL extend over the entire width direction WD with a dimension in the front-to-back direction LD of at least 60% of the waist region T of the front body F, since this can prevent the wearer's abdomen from getting cold before entering the water (before the disposable swimsuit gets wet). It is more preferable that the dimension in the front-to-back direction LD of the heat-retaining layer IL is 75% or more of the dimension in the front-to-back direction LD of the waist region T.

In the exterior body 12F, 12B of the example shown in FIG. 5 and FIG. 8, the two sheets 12S, 12H that form the outer sheet layer and the inner sheet layer are present as materials that cover the entire width direction WD with a dimension in the front-back direction LD of 60% or more of the waist region T of the front body F. Therefore, by making one or both of these sheet materials 12S, 12H a nonwoven fabric containing hollow fibers, the above-mentioned thermal insulation layer IL can be formed in one or two layers. On the other hand, since the sheet material 12S that constitutes the exterior body 12F, 12B of the example shown in FIG. 9 is one sheet, the thermal insulation layer IL can be formed in two layers by making the sheet material 12S a nonwoven fabric containing hollow fibers. The thermal insulation layer IL may form a part or all of the outer surface of the product, or may be covered in part or all by another layer on at least one of the inner surface side and the outer surface side of the product.

If only heat retention is considered, it is desirable to laminate as many heat retention layers IL as possible. For example, in the illustrated example, by making both the sheet materials 12S, 12H constituting the exterior bodies 12F, 12B nonwoven fabric layers containing hollow fibers, all of the nonwoven fabric layers constituting the exterior bodies can be heat retention layers IL. However, when compared at the same basis weight, nonwoven fabrics containing hollow fibers have higher water retention than nonwoven fabrics made only of solid fibers, so if the surface in contact with the skin is made of nonwoven fabrics made of hollow fibers, the wet feeling tends to persist even after the disposable swimsuit is not in water after it gets wet, which may reduce heat retention and make the wearer feel worse. The reason why nonwoven fabrics containing hollow fibers have higher water retention than nonwoven fabrics made only of solid fibers when compared at the same basis weight and hydrophilicity is not clear, but it is probably due to the larger surface area of hollow fibers, and even if both are hydrophobic or water-repellent nonwoven fabrics, the nonwoven fabrics containing hollow fibers have higher water retention. Therefore, it is preferable to provide a cover layer CL inside the heat-retaining layer IL, with a front-to-back dimension of at least 60% (more preferably at least 75%) of the heat-retaining layer IL, across the entire width, and to form the surface that comes into contact with the wearer's skin with this cover layer CL, and to form this cover layer CL from a nonwoven fabric made only of solid fibers, since this makes it difficult for the disposable swimsuit to feel wet even after it gets wet.

The heat retention of the hollow fiber nonwoven fabric forming the heat-retaining layer IL can be determined as appropriate, but a maximum heat flux (qmax) measured in accordance with JIS L 1927:2020 "Method for evaluating the coolness of textile products" of 0.05 to 0.08 J/cm ² sec, particularly 0.05 to 0.07 J/cm ² sec, is preferred because it provides excellent heat retention (low thermal conductivity). The maximum heat flux can be measured, for example, using a KES-F7 Thermo Lab manufactured by Kato Tech Co., Ltd.

Nonwoven fabrics containing hollow fibers may contain solid fibers mixed in to adjust various properties as long as the desired heat retention can be achieved, but nonwoven fabrics containing 100% hollow fibers (no solid fibers) are preferred from the standpoint of light weight and flexibility.

The hollow ratio of the hollow fiber can be appropriately determined as long as the desired heat retention can be achieved, but is preferably 10 to 40%, and more preferably 15 to 25%. If the hollow ratio is too low, it becomes difficult to ensure heat retention, and if it is too high, there is a risk of insufficient strength. The hollow ratio means the average value of the values calculated for 100 fibers by imaging a cut surface of the fiber with an electron microscope, determining the cross-sectional area of the entire fiber including the hollow portion and the cross-sectional area of the hollow portion based on the obtained image, and calculating the following formula:
Hollow ratio (%) = (cross-sectional area of hollow part / cross-sectional area of entire fiber) x 100

The fiber diameter of the hollow fibers can be determined as appropriate as long as the desired heat retention can be achieved, but for the above-mentioned hollow ratio, the average fiber diameter is preferably 9 to 23 μm, and more preferably 13 to 19 μm. The average fiber diameter refers to the average fiber diameter measured for 100 randomly selected fibers when observing the hollow fiber nonwoven fabric with an optical microscope.

The fineness of the hollow fibers can be appropriately determined as long as the desired heat retention can be achieved, but in the case of polyolefin-based fibers, it is preferably 0.5 to 3.0 dtex, and more preferably 1.0 to 2.0 dtex. When the above-mentioned cover layer CL is provided, the fineness of the solid fibers is preferably 0.5 to 4.0 dtex, and more preferably 1.0 to 3.0 dtex.

The cross-sectional shape of the hollow fiber may be circular or irregular (C-shaped, or having 4 to 8 fins, etc.). The hollow portion of the hollow fiber may have one or many holes that connect to the outer surface of the fiber, or may not have such an opening. Furthermore, the hollow portion that is continuous in the length direction of the fiber may be provided in a single or multiple locations at the center or eccentric positions of the fiber.

The material of the hollow fibers can be appropriately selected, and can be selected from, for example, polyolefins such as polyethylene or polypropylene, polyesters such as polyethylene terephthalate, polyamides, and other synthetic fibers without any particular limitation, and can also be used in combination. The hollow fibers may be non-crimped or crimped. In addition, the hollow fibers are preferably hydrophobic or water-repellent fibers (including fibers that have become water-repellent due to a water repellent agent). From the viewpoint of strength, the hollow fiber nonwoven fabric used in the heat-retaining layer IL is preferably a long fiber nonwoven fabric such as a spunbonded nonwoven fabric, but may also be a short fiber nonwoven fabric. The bonding (intertwining) method of the fibers of the hollow fiber nonwoven fabric can be any known method without any particular limitation, but from the viewpoint of strength, thermal bonding such as heat embossing or air-through is preferable. The material of the solid fibers can also be appropriately determined, and can be selected from, for example, polyolefins such as polyethylene or polypropylene, polyesters such as polyethylene terephthalate, polyamides, and other synthetic fibers without any particular limitation.

The basis weight of the hollow fiber nonwoven fabric can be determined as appropriate, but is preferably 10 to 20 g/ ^m2 , and more preferably 10 to 18 g/ ^m2 . The thickness of the hollow fiber nonwoven fabric can be determined as appropriate, but is preferably 0.1 to 0.3 mm, and more preferably 0.15 to 0.25 mm. When the cover layer CL is provided, the basis weight of the solid fibers can be determined as appropriate, but is preferably 10 to 30 g/ ^m2 , and more preferably 15 to 25 g/ ^m2 .

5, 8, and 9, the waist part W has an inner waist layer (one layer in the examples shown in Figs. 5 and 9, and multiple layers in the example shown in Fig. 8) located inside the waist elastic member 17, and an outer waist layer (only one layer in the examples shown in Figs. 8 and 9, and one layer and multiple layers in the example shown in Fig. 5) located outside the waist elastic member 17, and all of the inner waist layer and the waist elastic member 17 are continuously joined to the adjacent layers at least in the width direction WD. Such a waist part W can change between an expanded state in which the inner waist layer and the outer waist layer have no shrinkage wrinkles, and a natural length state in which the inner waist layer and the outer waist layer have shrinkage folds formed by shrinking in the width direction WD together with the waist elastic member 17, and when worn, the inner surface of the waist part W, which has a certain degree of shrinkage wrinkles, comes into contact with the wearer's skin. In addition, in a waist part W with such a structure, the shrinkage wrinkles of the waist part W are in the shape shown in Fig. 10. However, if these shrinkage wrinkles are large, a continuous gap is likely to form in the front-to-back direction LD between the inner surface of the waist part W and the skin, which may promote cooling of the abdominal area and may promote the ingress and egress of water after entering water, which may lead to the leakage of excrement.

In contrast, if the innermost layer of the waist inner layer is a specific hollow fiber nonwoven fabric that is particularly easily compressed, i.e., a spunbond nonwoven fabric made of polyolefin hollow fibers with a fineness of 1.0-2.0 dtex and a hollow ratio of 10-40%, a basis weight of 10-20 g/ ^m2 , and a thickness of 0.1-0.3 mm, it will be more easily compressed (e.g., the compression energy WC will be large, e.g., about 0.025-0.040 N·cm/ ^cm2 , especially about 0.028-0.040 N·cm/ ^cm2 ) than a nonwoven fabric with a similar solid fiber, and the convex parts of the shrinkage wrinkles formed in the waist inner layer will be lower. As a result, the adhesion of the skin surface in the waist part W is improved, the prevention of chilling of the abdominal area is improved, and the ingress and egress of water after entering water and the resulting leakage of excrement can be suppressed.

For example, in the illustrated example, the innermost layer of the waist inner layer is formed from sheet material 12S, and by using the specific hollow fiber nonwoven fabric described above as this sheet material 12S, the convex parts of the shrinkage wrinkles formed on the waist inner layer become lower, resulting in better adhesion to the skin surface in the waist area.

<Effectiveness Confirmation Test>
Two types of pants-type disposable swimsuits (sample 1 and sample 2) having the structure shown in Figures 1 to 6 and differing only in the sheet material 12S located on the outside of the outer casings 12F and 12B were produced, and the following thermal conductivity test and waist thickness measurement were performed.

Sample 1 used a hollow fiber nonwoven fabric as the sheet material 12S located on the outside of the exterior bodies 12F, 12B, and Sample 2 was similar to Sample 1 except that a solid fiber nonwoven fabric was used as the sheet material 12S located on the outside of the exterior bodies 12F, 12B. Table 1 shows the specifications of the spunbond nonwoven fabric used as the sheet material 12S of the exterior bodies 12F, 12B in the disposable swimsuits of Samples 1 and 2. In the disposable swimsuits of Samples 1 and 2, the sheet material 12H located on the inside of the exterior bodies 12F, 12B was a PP spunbond nonwoven fabric (solid fiber with a circular cross section, no crimp) with a fineness of 2.0 dtex, a basis weight of 15 g/ ^m2 , and a thickness of 0.18 mm.

The waist elastic members 17 of Samples 1 and 2, in both the front body F and the back body B, were spandex with a thickness of 580 dtex, and were fixed to the outer sheet layer and the inner sheet layer in a stretched state with an elongation rate of 280%. In addition, six waist elastic members 17 were provided in both the front body F and the back body B, spaced 6 mm apart (the distance between the waist elastic member 17 closest to the waist opening and the waist opening in the front-to-back direction was 4 mm).

The waist lower elastic members 15, 19 and cover elastic member 16 of samples 1 and 2 were made of spandex with a thickness of 430 dtex in both front body F and back body B, and were fixed to the outer sheet layer and inner sheet layer in a stretched state with a stretch rate of 300%. 18 waist lower elastic members 19 in front body F were provided at intervals of 5 mm (the distance between the waist lower elastic member 19 closest to the waist opening and the waist opening in the front-to-back direction was 39 mm). 18 waist lower elastic members 15 in back body B were provided at intervals of 5 mm (the distance between the waist lower elastic member 15 closest to the waist opening and the waist opening in the front-to-back direction was 39 mm). 3 cover elastic members 16 in back body B were provided at intervals of 10 mm (the distance between the cover elastic member 16 closest to the waist opening side and the waist lower elastic member 15 furthest from the waist opening in the front-to-back direction was 5 mm).

In samples 1 and 2, the waist elastic member 17, the waist lower elastic members 15 and 19, and the cover elastic member 16 were continuously coated in the longitudinal direction with hot melt adhesive at a rate of 0.05 g/m on the outer peripheral surface, and fixed to the outer sheet layer and the inner sheet layer. In the waist portion W, hot melt adhesive was coated in a spiral pattern at a rate of 5 g/ ^m2 to fix the folded portion 12r to the facing surface. The inner and outer joints 202 (see FIG. 2) were formed by coating the hot melt adhesive in a signature pattern at a rate of 3 g/ ^m2 in a rectangular region covering almost the entire overlapping portion of the inner body 200 and the outer bodies 12F and 12B.

(Thermal Conductivity Test)
As shown in Fig. 11, a temperature measuring sensor 101 was sandwiched between the front body F and the back body B of a disposable swimsuit sample 100 in a natural length state, and the waist opening WO and the leg opening LO were sealed with packing tape 102 so that air would not enter or exit through the waist opening WO and the leg opening LO between the space between the front body F and the back body B and the space outside the sample. A temperature and humidity sensor THA-3001 from T&D Corporation was used as the temperature measuring sensor 101, and this sensor was attached to the company's data logger TR-72nw for measurement. The temperature measuring sensor 101 was also positioned so as to overlap the absorbent body 56 and the exterior body 12F (see Fig. 11). In this state, the sample was placed in a thermostatic chamber at 55°C and left to stand, and the measurement results from the temperature measuring sensor were obtained over time.

(Observation of unevenness and thickness measurement of waist area)
The rear outer body 12B of the disposable swimsuit sample was cut along the front-to-back direction LD at a location adjacent to the center of the left and right side seal portions 12A in the width direction WD, and the front outer body 12F was then placed on a flat surface in its natural length, and the dimension in the width direction WD between the left and right side seal portions 12A at the waist portion W was measured with a ruler to obtain the first dimension. Next, the left and right side seal portions 12A of the front outer body 12F are grasped in an unfolded state with a pair of gripping tools set on a tensile testing machine, and while maintaining the front outer body 12F flat and the side seal portions 12A parallel to each other, the front outer body 12F is stretched in the width direction WD to twice the first dimension (elongation rate 200%).In this state, using a digital microscope (e.g., VHX-1000 manufactured by Keyence Corporation), an image of the edge of the waist opening WO is photographed along the surface of the front outer body 12F and from a direction perpendicular to the edge of the waist opening WO.Based on the obtained image, the apparent thickness of any three points on the edge of the waist opening WO is measured, and the average value is taken as the thickness of the waist portion W.

(Test Results)
The measurement results of the thermal conductivity test are shown in Fig. 12. From the results, it was found that Sample 1, which has one heat-insulating layer IL made of hollow fiber nonwoven fabric in the exterior bodies 12F, 12B, has superior heat retention properties compared to Sample 2, which does not have a layer of hollow fiber nonwoven fabric.

The thickness of the waist portion W at 200% stretch was 0.5 mm for Sample 1, which had a layer of a specific hollow fiber nonwoven fabric on the innermost and outermost surfaces of the waist portion W, and 0.7 mm for Sample 2, which did not have a layer of hollow fiber nonwoven fabric. In addition, visual observation of the unevenness of the waist portion W at 150% stretch confirmed that the convex parts of the shrinkage wrinkles formed on the innermost surface of the waist portion W in Sample 1 were clearly lower (the concave parts were shallower) than those in Sample 2.

<Explanation of terms used in the specification>
As used herein, the following terms have the following meanings unless otherwise specified in the specification.

The "front-rear direction" refers to the direction indicated by the symbol LD in the figure (longitudinal direction), and the "width direction" refers to the direction indicated by the symbol WD in the figure (left-right direction), with the front-rear direction and the width direction being perpendicular to each other.

- "Front side" means the side closest to the wearer's skin when worn, and "back side" means the side farthest from the wearer's skin when worn.

- "Front side" means the side of the component that is closest to the wearer's skin when worn, and "back side" means the side that is away from the wearer's skin when worn.

"Elongation rate" refers to the value when the natural length is 100%. For example, an elongation rate of 200% is synonymous with an elongation ratio of 2 times.

- "Gel strength" is measured as follows. 1.0 g of superabsorbent polymer is added to 49.0 g of artificial urine (a mixture of urea: 2 wt%, sodium chloride: 0.8 wt%, calcium chloride dihydrate: 0.03 wt%, magnesium sulfate heptahydrate: 0.08 wt%, and ion-exchanged water: 97.09 wt%) and stirred with a stirrer. The resulting gel is left in a thermo-hygrostat at 40°C x 60% RH for 3 hours, then returned to room temperature, and the gel strength is measured with a curd meter (I.techno Engineering: Curdmeter-MAX ME-500).

・"Basis weight" is measured as follows. After pre-drying the sample or test piece, leave it in a test room or device under standard conditions (test location: temperature 23±1°C, relative humidity 50±2%) until it reaches a constant weight. Pre-drying refers to bringing the sample or test piece to a constant weight in an environment at a temperature of 100°C. Note that pre-drying is not necessary for fibers with an official moisture regain of 0.0%. Using a sample collection template (100mm x 100mm), cut out a sample measuring 100mm x 100mm from the test piece that has reached a constant weight. Measure the weight of the sample and multiply it by 100 to calculate the weight per square meter, which is the basis weight.

The "thickness" of the nonwoven fabric etc. (excluding the waist portion described above) is automatically measured using an automatic thickness measuring device (KES-G5 handy compression measurement program) under the conditions of a load of 0.098 N/cm ² and a pressurized area of 2 cm ² .

- Water absorption is measured according to JIS K7223-1996 "Water absorption test method for superabsorbent resins."

The water absorption rate is the "time to the end point" when 2 g of superabsorbent polymer and 50 g of saline are used to perform the JIS K7224-1996 "Test method for water absorption rate of superabsorbent polymers."

- "Expanded state" means a flat, unfolded state without contraction (including any contraction, such as contraction due to elastic members) or sagging.

- Unless otherwise specified, the dimensions of each part refer to the dimensions in the unfolded state, not the natural length.

-If there is no description of the environmental conditions for a test or measurement, the test or measurement shall be performed in a test room or equipment under standard conditions (the test location shall be a temperature of 23±1°C and a relative humidity of 50±2%).

This invention can be used for pants-type disposable swimwear.

11...Liquid-impermeable sheet, 12A...Side seal portion, 12B...Rear outer body, 12F...Front outer body, 13...Cover nonwoven fabric, 16...Cover elastic member, 17...Waist elastic member, 18...Unnecessary elastic member, 200...Inner body, 201, 202...Inner and outer joints, 30...Top sheet, 40...Intermediate sheet, 50...Absorbent element, 56...Absorbent body, 58...Wrapping sheet, 60...Rising gathers, 6 0A...tip side portion, 60B...base side portion, 62...gathered nonwoven fabric, 67...folded portion, 68...free portion, F...front body, B...back body, A1...non-stretchable region, A2...stretchable region, C...buttocks cover portion, L...middle region, LD...front-to-back direction, T...torso region, U...lower waist portion, W...waist portion, WD...width direction, WO...waist opening, LO...leg opening, IL...insulating layer, CL...cover layer.

Claims (4)

A pants-type disposable swimsuit having a tubular waist region continuing in a waist direction, an intermediate region extending from a lower end of a front portion of the waist region through a crotch area to a lower end of a rear portion of the waist region, a waist opening, and a pair of left and right leg openings,
An exterior body that forms at least the waist area;
an inner body attached to the outer body so as to extend from a front portion of the waist region through the crotch area to a rear portion of the waist region;
An absorbent body incorporated in the inner body,
At least the front portion of the exterior body has a thermal insulation layer that is 60% or more of the waist area in the front-rear direction and extends across the entire width direction,
The heat-retaining layer is a nonwoven fabric containing hollow fibers,
At least the front portion of the exterior body has a cover layer that is located at the innermost part of the exterior body and includes a portion that has a front-to-rear dimension of 60% or more of the thermal insulation layer and extends across the entire width direction,
a portion of the cover layer that is located on the innermost side of the exterior body and does not overlap with the interior body forms a surface of the exterior body that contacts the skin of a wearer,
the cover layer is a nonwoven fabric consisting of solid fibers,
The heat-retaining layer and the cover layer are both made of a hydrophobic nonwoven fabric or a water-repellent nonwoven fabric.
A pants-type disposable swimsuit characterized by: The heat-retaining layer is a spunbond nonwoven fabric having a basis weight of 10 to 20 g/m ² and a thickness of 0.1 to 0.3 mm, the basis weight being made of polyolefin hollow fibers having a fineness of 0.5 to 3.0 dtex and a hollow ratio of 10 to 40%.
The pants-type disposable swimsuit according to claim 1. the waist region has a waist portion forming an edge of the waist opening, and a lower waist portion which is a portion closer to the leg openings than the waist portion;
The portion of the outer body located at the waist portion has a plurality of elongated waist elastic members arranged widthwise at intervals from one another, a single or multiple inner waist layer located inside the waist elastic members, and a single or multiple outer waist layer located outside the waist elastic members,
All of the waist inner layers and the waist elastic members are continuously joined to adjacent layers at least in the width direction;
a portion of the exterior body located in the waist portion is capable of changing between an expanded state in which the waist inner layer and the waist outer layer have no shrinkage wrinkles and a natural length state in which the portion shrinks in the width direction together with the waist elastic member to form shrinkage folds in the waist inner layer and the waist outer layer;
The innermost layer of the waist inner layers is the heat retaining layer and forms a surface that contacts the wearer's skin.
3. The pants-type disposable swimsuit according to claim 2. A portion of the exterior body that forms the waist region includes an elastic member, the heat-retaining layer adjacent to an outer side of the elastic member, and the cover layer adjacent to an inner side of the elastic member,
the nonwoven fabric forming the cover layer extends only from an end of the portion of the outer cover that forms the waist region on the leg opening side to a waist portion that forms an edge of the waist opening, the nonwoven fabric forming the heat retaining layer has a folded portion that is folded back on the inside of the nonwoven fabric forming the cover layer at the edge of the waist opening, and the folded portion extends only to the middle of the waist region in the front-to-rear direction,
an inner surface of a region between an edge of the waist region on the leg opening side and an edge of the folded-back portion on the leg opening side of the outer cover is formed by the cover layer;
In the outer body, a portion of the region between the edge of the leg opening side of the portion forming the waist region and the edge of the leg opening side of the folded-back portion, which does not overlap with the inner body, forms a surface of the outer body that contacts the skin of the wearer.
The pants-type disposable swimsuit according to any one of claims 1 to 3.

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