JP2016067435A - Underpants-type disposable diaper and manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an underpants-type disposable diaper with high portability, and manufacturing method thereof.SOLUTION: Both sides of a front piece and both sides of a back piece are bonded to each other to form side seal parts 12A and to form a waist opening WO and leg openings. The underpants-type disposable diaper includes a first area T defined as a longitudinal range having the side seal parts 12A, and a second area L defined as a range in the longitudinal direction of parts forming the leg openings. At least the longitudinal intermediate part of the second area L is folded in between both-side parts of the front/rear thereof to form a folded part 70.SELECTED DRAWING: Figure 10

Description

  The present invention relates to a pants-type disposable diaper having a compact product form and a method for manufacturing the same.

  The pants-type disposable diaper includes an exterior body that constitutes a front body and a back body, and an interior body including an absorbent body that is fixed to the inner surface of the exterior body, and the front body and the back body of the exterior body are on both sides. Are joined together to form a waist opening and a pair of left and right leg openings.

  A user of a pants-type disposable diaper may carry a replacement diaper when going out. When carrying such a replacement diaper, leave it in the packaging bag of the product and carry it alone in a portable bag, or carry it in a bag or bag with other items. To be done.

  However, conventional pants-type disposable diapers are not particularly folded in the product state, they are flat but flexible and have a large area, and the shape that forms the legs is affixed. Some bags and bags were difficult to accommodate and had difficulty in portability. In this case, the user may fold it into an arbitrary shape. However, it is difficult to store the bag or bag in the bag or bag because of its shape recovery by simply folding it, and the bag or bag is restored to its original shape. There was also a fear.

JP 2009-273653 A JP2013-208325A JP-A-2005-329106

  Then, the main subject of this invention is providing the underpants type disposable diaper of the product form which is excellent in portability, and its manufacturing method.

The present invention that has solved the above problems is as follows.
<Invention of Claim 1>
The waist opening and the leg opening are formed by joining the both sides of the front body and the both sides of the back body to form the side seal part,
A first region defined as a front-rear direction range having a side seal portion, and a second region defined as a front-rear direction range of a portion forming a leg opening,
At least the front-rear direction intermediate part of the second region is folded between the front and rear side parts to form a folded part,
A pants-type disposable diaper characterized by that.

(Function and effect)
By thus folding the second region, which is the crotch side portion, inwardly to form the folded portion, the length of the product is shortened, the shape is close to a rectangle, and the thickness is partially increased. The stiffness becomes stronger by that amount, and the second region is folded inward, so that the maintainability of the folded state is also high. Therefore, it is excellent in portability. At the time of use, it can be set as a use form by taking out a folding part outside.

<Invention of Claim 2>
The pants-type disposable diaper according to claim 1, wherein at least a part of the opposing surface of the folded portion is releasably joined.

(Function and effect)
Thus, if the opposing surface of a folding part is joined so that peeling is possible, the maintainability of a folded state will become high. At the time of use, it can be set as a use form by peeling the joint and taking out the folded portion to the outside.

<Invention of Claim 3>
The pants-type disposable diaper according to claim 1 or 2, wherein a folded edge of a facing surface of the folded portion is located in the second region.

(Function and effect)
If comprised in this way, since a folding depth is shallow, manufacture becomes easy. In particular, continuous production as in the production method described later is also facilitated.

<Invention of Claim 4>
The pants-type disposable diaper according to claim 1 or 2, wherein a folded edge of an opposing surface of the folded portion is located in the first region.

(Function and effect)
In the first region, the front body and the back body are joined by the side seal portion to form an annular shape. Therefore, when the folded portion is folded up to this region, the folded state is more maintainable.

<Invention of Claim 5>
An interior body that individually or integrally configures the front body and the back body, and an interior of the excrement absorber provided inside the exterior body so as to extend from the front body to the back body through the crotch. The pants type has a waist opening and a leg opening formed by joining the both sides of the exterior body of the front body and the both sides of the exterior body of the back body to form a side seal part. In the manufacturing method of disposable diapers,
Forming an exterior belt-like body that repeats and continues in the MD direction so that the width direction and the MD direction of the portion to be the exterior body coincide with each other;
While the outer band is transported so that the width direction of the diaper is the MD direction in the same arrangement as the unfolded state of the diaper, a separately manufactured unfolded portion is provided on each of the outer band bodies as the individual outer body. An inner body attachment step in which the inner layer assembly is formed by sequentially joining the inner bodies in a state to form an inner layer assembly in which the portions serving as diapers are continuous in the MD direction in a deployed state;
A folding step in which the inner layer assembly is folded in the CD direction to form a folded band-like body;
A folded portion forming step of forming a folded portion by folding a portion including a bifold fold in the bifold band-like body between the front body side portion and the back body side portion;
Joining the outer body of the front body and the outer body of the back body at the parts that will be both sides of each diaper, cutting the outer body of the front body and the back body of the front body at the boundary of each diaper, Obtaining a diaper, side joining and disconnecting step;
A method for producing a pants-type disposable diaper, comprising:

(Function and effect)
According to this manufacturing method, the underpants-type disposable diaper of the invention according to claim 1 can be manufactured with a simple change that simply adds a folding part forming step to the conventional manufacturing method.

  As described above, according to the present invention, a pants-type disposable diaper having a product form excellent in portability and a manufacturing method thereof are provided.

It is a top view in the state where the diaper was developed showing the inside of a pants type disposable diaper. It is a top view in the state where the diaper was developed showing the outer surface of a pants type disposable diaper. FIG. 3 is a 3-3 cross-sectional view of FIG. 1. FIG. 4 is a sectional view taken along the line 4-4 in FIG. 1. FIG. 5 is a sectional view taken along line 5-5 in FIG. 1. It is a top view in the state where the diaper was developed showing only the principal part of a pants type disposable diaper. It is sectional drawing which shows only the principal part of a pants type disposable diaper. It is a front view of a pants type disposable diaper. It is a rear view of a pants type disposable diaper. It is a left view of a pants type disposable diaper. It is a side view of an interior body part. It is a top view which shows a manufacture flow. (A) It is the schematic of a folding part formation process, (b) It is the 7-7 cross-sectional schematic.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
<Pants-type disposable diapers>
1 to 11 show an example 100 of a pants-type disposable diaper. The dotted pattern portion in the cross-sectional view shows an adhesive as a joining means for joining the constituent members, and is a fixed portion of the elastic elastic member by applying solid, bead, curtain, summit or spiral such as hot melt adhesive. Instead of or together with this, it is formed by coating on the outer peripheral surface of an elastic stretchable member such as a comb gun or a sheathing coating. As the joining means for joining the constituent members, welding means such as heat sealing and ultrasonic sealing can be used.

  The pants-type disposable diaper 100 according to the present embodiment includes outer bodies 12F and 12B that constitute the front body F and the rear body B, and outer bodies 12F and 12B that extend from the front body F to the back body B through the crotch. The inner body 200 is provided on the inner side, and both side portions of the outer body 12F of the front body F and both sides of the outer body 12B of the rear body B are joined to form a side seal portion 12A. is there. Symbol Y indicates the total length of the diaper in the unfolded state (vertical length 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 symbol X indicates the total width of the diaper in the unfolded state. Is shown.

  The interior body 200 is a portion that absorbs and holds excrement such as urine, and the exterior bodies 12F and 12B are portions that support the interior body 200 with respect to the wearer's body. In this embodiment, the upper openings of the exterior bodies 12F and 12B serve as waist openings WO through which the wearer's torso passes, and the lower edges of the exterior bodies 12F and 12B and the side edges of the interior body 200 on both sides in the width direction of the interior body 200, respectively. The enclosed part is a leg opening LO through which the leg passes.

  Moreover, the pants-type disposable diaper 100 of this embodiment forms a first region defined as a longitudinal range (a longitudinal range extending from the waist opening WO to the upper end of the leg opening LO) having the side seal portion 12A, and the leg opening LO. And a second region L defined as a front-rear direction range (between a longitudinal region having the side seal portion 12A of the front body F and a longitudinal region having the side seal portion 12A of the rear body B). The first region T can be divided into a “waist edge” W that conceptually forms an edge of the waist opening, and a “waist lower part” U that is a lower part than this. Normally, when the first region T has a boundary in which the width direction expansion / contraction stress changes (for example, the thickness or elongation rate of the elastic expansion / contraction member changes), the waist opening WO side is closer to the waist edge than the waist opening WO side boundary. When there is no such boundary, the waist opening WO side becomes the waist edge W with respect to the absorbent body 56 or the interior body 200. These lengths in the vertical direction vary depending on the size of the product and can be determined as appropriate. For example, the waist edge W may be 15 to 40 mm, and the waist lower portion U may be 65 to 120 mm. On the other hand, both side edges of the second region L are bundled along the circumference of the wearer's leg, and this is a part into which the wearer's leg is put. As a result, the unfolded pants-type disposable diaper has a substantially hourglass shape as a whole.

(Interior body)
The interior body 200 can take any shape, but is rectangular in the illustrated form. As shown in FIGS. 3 to 5, the interior body 200 includes a surface sheet 30 on the body side, a liquid-impermeable sheet 11, and an absorption element 50 interposed therebetween. Yes, it is the main body that takes up the absorption function. 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 the liquid that has passed through the top sheet 30 to the absorbent element 50. Shows a three-dimensional gather 60 that stands on the body side and is provided on both sides of the interior body 200 in order to prevent excrement from leaking to both sides of the interior body 200.

(Surface sheet)
The top sheet 30 has a property of transmitting liquid, and examples thereof include a porous or non-porous nonwoven fabric, a porous plastic sheet, and the like. Of these, the nonwoven fabric is not particularly limited as to what the raw fiber is. For example, synthetic fibers such as olefins such as polyethylene and polypropylene, polyesters and polyamides, recycled fibers such as rayon and cupra, natural fibers such as cotton, and mixed fibers and composite fibers using two or more of them. Etc. can be illustrated. Furthermore, the nonwoven fabric may be manufactured by any processing. Examples of the processing method include known methods such as a spunlace method, a spunbond method, a thermal bond method, a melt blown method, a needle punch method, an air through method, and a point bond method. For example, if flexibility and drapeability are required, the spunbond method and spunlace method are preferable. If bulkiness and softness are required, the air-through method, point bond method, and thermal bond method are preferable processing methods. .

  Further, the top sheet 30 may be composed of one sheet or may be composed of a laminated sheet obtained by bonding two or more sheets. Similarly, the top sheet 30 may be composed of one sheet or two or more sheets in the planar direction.

  When the three-dimensional gather 60 is provided, both sides of the top sheet 30 pass between the liquid-impermeable sheet 11 and the three-dimensional gather 60 to the back side of the absorbent element 50 to prevent the liquid from penetrating. It is preferable to adhere to the impermeable sheet 11 and the three-dimensional gather 60 with a hot melt adhesive or the like.

(Intermediate sheet)
An intermediate sheet (also referred to as “second sheet”) 40 having a higher liquid permeation rate than the top sheet 30 can be provided to quickly transfer the liquid that has passed through the top sheet 30 to the absorber. This intermediate sheet 40 not only improves the absorption performance of the absorbent by quickly transferring the liquid to the absorbent body, but also prevents the “reversed” phenomenon of the absorbed liquid from the absorbent body, so that the top sheet 30 is always dried. It can be made into the state which carried out. The intermediate sheet 40 can be omitted.

Examples of the intermediate sheet 40 include the same material as the top sheet 30, spunlace, spunbond, SMS, pulp nonwoven fabric, mixed sheet of pulp and rayon, point bond, or crepe paper. In particular, an air-through nonwoven fabric is preferable because it is bulky. It is preferable to use a core-sheath composite fiber for the air-through nonwoven fabric. In this case, the resin used for the core may be polypropylene (PP), but polyester (PET) having high rigidity is preferable. Basis weight is preferably ^{20~80g / m 2, 25~60g / m} 2 is more preferable. The thickness of the raw fiber of the nonwoven fabric is preferably 2.2 to 10 dtex. In order to make the nonwoven fabric bulky, it is also preferable to use an eccentric fiber, a hollow fiber, or an eccentric and hollow fiber that does not have a core at the center as the mixed fiber of all or part of the raw fiber.

  The intermediate sheet 40 in the illustrated form is disposed in the center shorter than the width of the absorber 56, but may be provided over the entire width. The length of the intermediate sheet 40 in the longitudinal direction may be the same as the length of the absorbent body 56 or may be within a short length range centered on the region that receives the liquid.

(Liquid impervious sheet)
The material of the liquid-impermeable sheet 11 is not particularly limited. For example, a plastic film made of an olefin resin such as polyethylene or polypropylene, a laminated nonwoven fabric provided with a plastic film on the surface of the nonwoven fabric, or a plastic film For example, a laminated sheet in which a nonwoven fabric or the like is laminated and bonded to each other can be exemplified. For the liquid-impermeable sheet 11, it is preferable to use a liquid-impervious and moisture-permeable material that has been preferred in recent years from the viewpoint of preventing stuffiness. As a plastic film having moisture permeability, a microporous plastic film obtained by kneading an inorganic filler in an olefin resin such as polyethylene or polypropylene, forming a sheet, and then stretching in a uniaxial or biaxial direction. Is widely used. In addition, non-woven fabric using micro-denier fibers, leakproof reinforcement by reducing the voids of the fibers by applying heat or pressure, and methods such as applying a superabsorbent resin or hydrophobic resin or water repellent Thus, a sheet that is liquid-impermeable without using a plastic film can also be used as the liquid-impermeable sheet 11.

  The liquid-impermeable sheet 11 has a width that fits on the back side of the absorbent element 50 as shown in the drawing, and in order to improve leakage prevention, the liquid-impermeable sheet 11 wraps around both sides of the absorbent element 50 and faces the side surface 30 of the absorbent element 50. It can also extend to both sides of the. The width of this extended portion is suitably about 5 to 20 mm on each of the left and right sides.

  Moreover, the excretion indicator from which a color changes by absorption of a liquid part can be provided in the inner side of the liquid-impermeable sheet 11, especially the absorber 56 side surface.

(Three-dimensional gather)
The three-dimensional gather 60 is a belt-like member that extends over the entire front-rear direction along both side portions of the interior body 200, blocks urine and soft stool that move in the lateral direction along the top sheet 30, and prevents side leakage. It is provided for this purpose. The three-dimensional gather 60 of the present embodiment is provided so as to stand up from the side portion of the interior body 200, the base side portion rises obliquely toward the center in the width direction, and the tip side portion from the intermediate portion has a width. It stands up diagonally outward in the direction.

  More specifically, the three-dimensional gather 60 folds the belt-shaped gather sheet 62 having a length equal to the length in the front-rear direction of the interior body 200 in the width direction and folds it into two. In addition, a plurality of elongated elastic elastic members 63 are fixed along the longitudinal direction at intervals in the width direction. A base end portion (an end portion on the side opposite to the sheet folding portion in the width direction) located on the opposite side to the front end portion of the three-dimensional gather 60 is an attachment portion 65 fixed to the back surface of the side edge portion of the interior body 200. A portion other than the attachment portion 65 is a protruding portion 66 (a portion on the folded portion side) protruding from the attachment portion 65. The projecting portion 66 includes a base side portion that extends toward the center in the width direction, and a tip side portion that is folded back outward in the width direction from the tip of the base side portion. This form is a surface contact type three-dimensional gather, but a line contact type three-dimensional gather (not shown) that is not folded outward in the width direction can also be employed. And the fixing means by material welding, such as a hot-melt adhesive (alternatively or in combination with this, a heat seal or an ultrasonic seal) is applied to the side surface of the topsheet 30 with both ends in the front-rear direction of the protruding portion 66 lying down. The front-rear direction fixing portion 67 is fixed to the front-rear direction intermediate portion, and the front-rear direction intermediate portion located between them is the non-fixed free portion 68. The free portion 68 is elongated along the front-rear direction. The elastic member 63 is fixed in an extended state.

The gather sheet 62 is made of a spunbond nonwoven fabric (SS, SSS, etc.), SMS nonwoven fabric (SMS, SSMMS, etc.), a melt-blown nonwoven fabric with excellent uniformity and concealment, and water repellent with silicon as necessary. A treated product can be suitably used, and the fiber basis weight is preferably about 10 to 30 g / m ² . As the elongated elastic elastic member 63, rubber thread or the like can be used. When spandex thread rubber is used, the thickness is preferably 470 to 1240 dtex, more preferably 620 to 940 dtex. The elongation rate at the time of fixation is preferably 150 to 350%, more preferably 200 to 300%. The term “elongation rate” means a value when the natural length is 100%. Further, as shown in the drawing, a waterproof film 64 can be interposed between the gather sheets folded in two.

  2-6 are preferable and, as for the number of the elongate elastic expansion-contraction members 63 provided in the free part of the three-dimensional gather 60, 3-5 are more preferable. The arrangement interval 60d is suitably 3 to 10 mm. If comprised in this way, in the range which has arrange | positioned the elongate elastic expansion-contraction member 63, it will become easy to contact | abut with respect to skin. The elongated elastic elastic member 63 may be disposed not only at the distal end side but also at the base side.

  The fixing target of the attachment portion 65 of the three-dimensional gather 60 can be an appropriate member such as the top sheet 30, the liquid-impermeable sheet 11, and the absorbent element 50 in the interior body 200.

  In the three-dimensional gather 60 thus configured, the contraction force of the elongated elastic elastic member 63 acts so that both ends in the front-rear direction are brought close to each other, but the both ends in the front-rear direction of the protruding portion 66 are fixed so as not to stand up. On the other hand, since they are non-fixed free portions, only the free portions stand up against the body side as shown in FIG. In particular, when the attachment portion 65 is positioned on the back surface side of the interior body 200, the three-dimensional gather 60 stands up so as to open outward in the width direction at the crotch portion and in the vicinity thereof. It comes in contact, and the fit is improved.

  The dimensions of the three-dimensional gather 60 can be determined as appropriate. In the case of an infant paper diaper, for example, as shown in FIG. 7, the standing height of the three-dimensional gather 60 (the length in the width direction of the protruding portion 66 in the unfolded state) W6 is It is preferably 15 to 60 mm, particularly 20 to 40 mm. In addition, the distance W3 between the folds located on the innermost side in a state where the three-dimensional gather 60 is folded flat so as to be parallel to the surface of the top sheet 30 is preferably 60 to 190 mm, particularly preferably 70 to 140 mm.

  Note that, unlike the illustrated embodiment, the three-dimensional gathers can be provided in double (two rows) on the left and right sides of the interior body 200.

(Absorption element)
The absorbent element 50 includes an absorbent body 56 and a packaging sheet 58 that wraps the entire absorbent body 56. The packaging sheet 58 can be omitted.

(Absorber)
The absorber 56 can be formed of an aggregate of fibers. As this fiber assembly, a filament assembly obtained by opening, as necessary, synthetic fiber tows (fiber bundles) such as cellulose acetate as well as short fibers such as cotton-like pulp and synthetic fibers Can also be used. The fiber basis weight can be set to, for example, about 100 to 300 g / m ² when cotton-like pulp or short fibers are stacked, and in the case of a filament aggregate, for example, about 30 to 120 g / m ^2. Can do. The fineness in the case of a synthetic fiber is 1-16 dtex, for example, Preferably it is 1-10 dtex, More preferably, it is 1-5 dtex. In the case of a filament aggregate, the filament may be a non-crimped fiber, but is preferably a crimped fiber. The crimped degree of the crimped fiber can be, for example, 5 to 75, preferably 10 to 50, and more preferably about 15 to 50 per inch. Further, a crimped fiber that is uniformly crimped is often used. It is preferable to disperse and hold superabsorbent polymer particles in the absorber 56.

  Although the absorbent body 56 may be rectangular, as shown in FIG. 6, as shown in FIG. 6, the hourglass has a front end portion, a rear end portion, and a narrow portion narrower than the front end portion and the rear end portion. The shape is preferable because the fit of the absorber 56 itself and the three-dimensional gather 60 around the legs is improved.

  Moreover, although the dimension of an absorber can be determined suitably, it is preferable to extend to the peripheral part of the interior body, or its vicinity in the front-back direction and the width direction. Reference numeral 56X indicates the width of the absorber 56.

(Superabsorbent polymer particles)
The absorber 56 can contain superabsorbent polymer particles in a part or all thereof. Superabsorbent polymer particles include “powder” in addition to “particles”. As the superabsorbent polymer particles 54, those used for this type of absorbent article can be used as they are, for example, by sieving (shaking for 5 minutes) using a 500 μm standard sieve (JIS Z8801-1: 2006). The ratio of particles remaining on the sieve is preferably 30% by weight or less, and the ratio of particles remaining on the sieve by sieving (shaking for 5 minutes) using a 180 μm standard sieve (JIS Z8801-1: 2006). Is preferably 60% by weight or more.

  The material of the superabsorbent polymer particles can be used without any particular limitation, but those having a water absorption of 40 g / g or more are suitable. High-absorbent polymer particles include starch-based, cellulose-based, and synthetic polymer-based starch-acrylic acid (salt) graft copolymers, saponified starch-acrylonitrile copolymers, and sodium carboxymethylcellulose crosslinks. Or an acrylic acid (salt) polymer can be used. As the shape of the superabsorbent polymer particles, a commonly used granular material is suitable, but other shapes can also be used.

  As the superabsorbent polymer particles, those having a water absorption rate of 70 seconds or less, particularly 40 seconds or less are preferably used. If the water absorption speed is too slow, the liquid supplied into the absorber 56 is likely to cause a so-called reverse return that returns to the outside of the absorber 56.

  Further, as the superabsorbent polymer particles, those having a gel strength of 1000 Pa or more are preferably used. Thereby, even if it is a case where it is set as the bulky absorber 56, the sticky feeling after liquid absorption can be suppressed effectively.

The basis weight of the superabsorbent polymer particles can be appropriately determined according to the amount of absorption required for the use of the absorber 56. Therefore, although it cannot be said unconditionally, it can be set to 50 to 350 g / m ² . If the amount of polymer is less than 50 g / m ^2, it is difficult to secure the absorption amount. When it exceeds 350 g / m ² , the effect is saturated.

  If necessary, the superabsorbent polymer particles can adjust the spraying density or spraying amount in the plane direction of the absorber 56. For example, it is possible to increase the application amount of the liquid excretion site as compared to other sites. When gender differences are taken into account, men can increase the front spray density (amount), while women can increase the center spray density (amount). In addition, a portion where no polymer exists locally (for example, in a spot shape) in the planar direction of the absorber 56 can also be provided.

(Packaging sheet)
When the packaging sheet 58 is used, as the material, tissue paper, particularly crepe paper, non-woven fabric, polylaminated non-woven fabric, a sheet with small holes, or the like can be used. However, it is desirable that the superabsorbent polymer particles be a sheet that does not escape. When a nonwoven fabric is used in place of the crepe paper, a hydrophilic SMS nonwoven fabric (SMS, SSMMS, etc.) is particularly suitable, and the material can be polypropylene, polyethylene / polypropylene composite material, or the like. The basis weight is preferably 5 to 40 g / m ² , particularly 10 to 30 g / m ² .

  The packaging form of the packaging sheet 58 can be determined as appropriate, but from the viewpoint of ease of manufacture and prevention of leakage of the superabsorbent polymer particles from the front and rear end edges, the cylinder is formed so as to surround the front and back surfaces and both side surfaces of the absorbent body 56. It is preferable that the front and rear edges of the absorbent body 56 are protruded from the front and back of the absorbent body 56, and the protruding portions are crushed in the front and back directions and joined by a joining means such as a hot melt adhesive.

(Crotch cover sheet)
On the back surface of the liquid-impermeable sheet in the interior body 200, a part of the exposed portion of the interior body 200 (for example, the entire front-rear direction of the portion exposed between the ventral-side exterior body 12F and the back-side exterior body 12B, The crotch portion cover sheet 12M may be attached so as not to extend to the front and rear ends of the interior body 200 and to cover the entire width direction side edges so as not to reach both side edges of the interior body 200). As the crotch portion cover sheet 12M, the same material as that used for exterior bodies 12F and 12B described later can be used.

(Exterior body)
The exterior bodies 12F and 12B include a front exterior body 12F that is a part constituting the front body F and a rear exterior body 12B that is a part constituting the rear body B. The front exterior body 12F and the rear exterior body 12B Are not continuous on the leg side and are spaced apart. The separation distance L8 can be about 150 to 250 mm. Although not shown in the drawings, the exterior body can be an integral body that continues from the abdomen to the back via the crotch, and in this case, the above-described crotch cover sheet 12M can be omitted. That is, the exterior bodies 12F and 12B that individually configure the front body F and the back body B in the present invention correspond to the former form, and the exterior body that integrally configures the front body F and the back body B to the latter form. Equivalent to.

  The exterior bodies 12 </ b> F and 12 </ b> B have a trunk periphery that is a longitudinal range corresponding to the first region T. In this embodiment, the front exterior body 12F does not have a portion corresponding to the second region L, but the rear exterior body 12B extends from the first region T to the second region L side. have. Although not shown, the front exterior body 12F is also provided with a collar cover portion that extends from the first region T to the second region L, a configuration that does not provide the collar cover portion although the inguinal cover portion is provided, or the front exterior body 12F. And the part corresponding to 2nd area | region L does not need to be provided in both the rear side exterior bodies 12B. In the illustrated embodiment, the lower edge of the collar cover portion 14 is curved, but may be formed in a straight line along the width direction, like the lower edge of the front exterior body 12F.

  As shown in FIGS. 3 to 5, the exterior bodies 12 </ b> F and 12 </ b> B are formed by laminating two sheet materials 12 </ b> S and 12 </ b> H and joining them by a joining means such as a hot melt adhesive or welding. The inner sheet material 12H positioned on the inner side extends only to the edge of the waist opening WO, but the outer sheet material 12S wraps around the edge on the waist side of the inner sheet material 12H and is folded inside. The folded portion 12r extends so as to cover up to the end on the waist side of the interior body 200.

The sheet materials 12S and 12H can be used without particular limitation as long as they are in sheet form, but are preferably non-woven fabrics. The nonwoven fabric is not particularly limited as to what the raw fiber is. For example, synthetic fibers such as olefins such as polyethylene and polypropylene, polyesters and polyamides, recycled fibers such as rayon and cupra, natural fibers such as cotton, and mixed fibers and composite fibers using two or more of them. Etc. can be illustrated. Furthermore, the nonwoven fabric may be manufactured by any processing. Examples of the processing method include known methods such as a spunlace method, a spunbond method, a thermal bond method, a melt blown method, a needle punch method, an air through method, and a point bond method. When using a nonwoven fabric, the basis weight is preferably about 10 to 30 g / m ² .

Moreover, it is preferable that the total weight of the exterior bodies 12F and 12B is about 20 to 60 g / m ² .

  And in the exterior bodies 12F and 12B, in order to improve the fit with respect to the trunk circumference, elongated elastic elastic members 15 to 17 and 19 such as thread rubber are provided between the sheet materials 12S and 12H at a predetermined elongation rate. Yes. As the elongated elastic elastic members 15 to 17 and 19, synthetic rubber or natural rubber may be used. For bonding the sheet materials 12S and 12H of the exterior bodies 12F and 12B and fixing the elongated elastic members 15 to 19 sandwiched between them, hot melt bonding or heat sealing or ultrasonic bonding by various coating methods is used. be able to. It is not preferable to firmly fix the entire exterior body 12F, 12B because the texture of the sheet is impaired. By combining these, it is preferable that the elongated elastic elastic members 15 to 17 and 19 are firmly bonded and the other portions are not bonded or are bonded weakly.

More specifically, between the inner surface of the inner sheet material 12H and the outer surface of the folded portion 12r of the outer sheet material 12S at the waist edge W of the exterior bodies 12F and 12B, the entire width direction is continuous. A plurality of waist edge elastic elastic members 17 are fixed in a state where they are spaced apart in the vertical direction and extended along the width direction at a predetermined extension rate. In addition, one or a plurality of the waist edge elastic elastic members 17 disposed in the region adjacent to the waist lower part U may overlap with the interior body 200 or may overlap with the interior body 200. You may each provide in the width direction both sides except a direction center part. The waist edge elastic elastic member 17 has 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, the cross-sectional area is 0.05 to 1.5 mm ² , particularly 0.1 to the rubber thread of 1.0mm about ^2), 3 to 22 present approximately at intervals of 4 to 12 mm, respectively elongation from 150% to 400%, preferably fixed in particular about 220-320%. Further, the waist edge elastic elastic members 17 need not all have the same thickness and elongation rate. For example, the elastic elastic members may have different thicknesses and elongation rates at the upper and lower portions of the waist edge W. .

  In addition, between the outer side surface of the inner sheet material 12H and the inner side surface of the outer sheet material 12S in the waist lower part U of the exterior bodies 12F and 12B, except for the central portion in the width direction overlapping the interior body 200, A plurality of waist lower elastic elastic members 15 and 19 made of an elongated elastic elastic member, which are continuous in the entire width direction at each part on both sides in the width direction, are spaced apart in the vertical direction and have a predetermined elongation rate. It is fixed in the state extended | stretched along the width direction.

The waist lower elastic elastic members 15 and 19 have a thickness of 155 to 1880 dtex, especially about 470 to 1240 dtex (in the case of synthetic rubber. In the case of natural rubber, the cross-sectional area is 0.05 to 1.5 mm ² , particularly 0.1. the rubber thread ~1.0mm about ^2), 1 to 15 mm, particularly 5 to 30 present approximately at intervals of 3 to 8 mm, respectively elongation 200-350%, preferably fixed in particular about 240-300%.

  Moreover, the width direction except for the center part of the width direction which overlaps with the interior body 200 between the outer surface of the inner sheet material 12H and the inner surface of the outer sheet material 12S in the collar cover portion 14 of the rear exterior body 12B. A plurality of cover elastic elastic members 16 made of an elongated elastic elastic member are provided in each part on both sides so as to be continuous over the entire width direction, spaced vertically and along the width direction at a predetermined elongation rate. It is fixed in the extended state.

The cover elastic elastic member 16 has a thickness of 155 to 1880 dtex, especially about 470 to 1240 dtex (in the case of synthetic rubber. In the case of natural rubber, the cross-sectional area is 0.05 to 1.5 mm ² , particularly 0.1 to 1. It is preferable to fix the thread rubber of about 0 mm ² ) at intervals of 5 to 40 mm, particularly 5 to 20 mm, and stretch ratios of 150 to 300%, particularly 180 to 260%, respectively.

  In the case where an inguinal cover is provided on the front exterior body 12F, a cover elastic member can be provided in the same manner.

  As shown in the drawing, the waist lower elastic elastic members 15 and 19 and the cover elastic elastic member 16 are respectively provided on both sides in the width direction except for a part or the whole of the portion overlapping the interior body 200. The interior body 200 does not shrink more than necessary in the width direction, so that it does not look bad or absorbs. In this form, in addition to the form in which the elastic stretchable member exists only on both sides in the width direction, the elastic stretchable member exists from one side of the width direction to the other side across the interior body 200, but overlaps the interior body 200. The elastic elastic member is finely cut in part or all of the part, and the contraction force does not act (substantially equivalent to not providing the elastic expansion / contraction member), and only the both sides in the width direction serve as the contraction force acting part. A configured form is also included. Of course, the arrangement of the waist lower elastic elastic members 15 and 19 and the cover elastic elastic member 16 is not limited to the above example, and the elastic force acts on the entire width direction including the portion overlapping the interior body 200. The waist lower elastic elastic members 15 and 19 and the cover elastic elastic member 16 may be partially or entirely provided from one side to the other side in the width direction across the interior body 200.

(Folding part)
Characteristically, as shown in FIGS. 8 to 11, at least a middle part in the front-rear direction of the second region L is folded between the front and rear side parts to form a folded part 70. In this way, the second region L, which is the crotch portion, is folded inward to form the folded portion 70, whereby the vertical length of the product is shortened, the shape is close to a rectangle, and the thickness is partially Although it increases, the stiffness becomes stronger, and the second region L is folded inward, so that the maintainability of the folded shape is also high. Therefore, it is excellent in portability. At the time of use, as shown by the two-dot chain line in FIGS.

  The folding depth 70d of the folding portion 70 may be determined as appropriate, but if it is too shallow, there is a risk that the folding portion 70 may come out of its own and the folded state may not be maintained. It is desirable to fold in the range of 45%. Further, when the folding edge 70e on the opposite surface of the folded portion 70 is positioned in the second region L, the folding depth 70d is relatively shallow, so that the manufacturing is facilitated (particularly as in the manufacturing method described later). However, when it is folded deeply so as to be located in the first region T, the front body F and the back body B are joined to each other by the side seal portion 12A to form an annular shape. Therefore, the maintainability of the folded shape is higher.

  In order to further improve the maintainability of the folded state, as shown in FIG. 11, at least a part of the opposed surface of the folded portion 70 (preferably the lower end portion) is preferably detachably joined by the joining means 70b. is there. As this joining means 70b, hot melt adhesive, welding means such as ultrasonic sealing and heat sealing, mechanical fasteners, adhesives and the like can be used. At the time of use, the part joined by the joining means 70b is peeled off, and the folded part 70 is brought out to the outside, so that it can be used.

  On the other hand, the conventional pants-type disposable diaper is not particularly folded in the product state, and the waist opening WO and the leg opening LO are in a freely openable / closable state. May become unsanitary. In particular, when the folding portion 70 is formed, the waist opening WO and the leg opening LO are likely to be opened due to the increase in the inner thickness and the spring action of the folding portion 70. Therefore, as shown in FIG. 11, it is also preferable that at least a part of the inner surface on the front body F side and the inner surface on the rear body B side facing each other is detachably joined by the joining means 80b to provide the temporary fixing portion 80. It is. As this joining means 80b, hot melt adhesive, welding means such as ultrasonic seal and heat seal, pressure sensitive adhesive and the like can be used. Providing such a temporary fixing portion 80 makes it difficult for the waist opening WO and the leg opening LO to open before use, and also makes it difficult for the facing surface of the interior body 200 to open, so that it is difficult for other articles or the like to enter inside. preferable. At the time of use, it can be set as a use form by peeling the part joined by the joining means 80b.

  The part to which the temporary fixing portion 80 is joined is not particularly limited, and may be the exterior bodies 12F and 12B or the interior body 200. However, as shown in the figure, the absorbent body 56 at the end on the waist side of the interior body 200 is provided. A portion that is not provided and is not provided with the elastic elastic members 15 to 17 and 19 on the exterior bodies 12F and 12B is preferable because a peeling mark of the temporary fixing portion 80 is difficult to hit the skin during use. This form includes a form in which the front and back end surfaces of the interior body 200 are joined together, as well as a form in which the exterior bodies 12F and 12B folded portions 12r covering the front and back ends of the interior body 200 are joined.

<Manufacturing method>
FIG.12 and FIG.13 has shown an example of the manufacturing method of the underpants type disposable diaper mentioned above. This production line has a lateral flow configuration in which the diaper width direction is the MD direction (machine direction, line flow direction), and the rear stretch body 12F and the rear exterior body 12B that become the ventral exterior body 12F here. The side elastic band 12b is formed, and the interior body 200 manufactured by another line is attached to the front elastic band 12f and the rear elastic band 12b. The front side elastic band 12f and the rear side elastic band 12b correspond to the exterior belt-like body of the present invention. In addition, in order to make an explanation easy to understand, members that are continuous in the manufacturing process are also denoted by the same reference numerals as those after manufacture.

  More specifically, this production line includes an elastic member attaching step 301, an elastic member cutting step 302, an exterior cutting and dividing step 304, a leg opening cutting step 305, an interior body attaching step 306, an exterior folding step 307, a folding step 308, A folded portion forming step 309 and a side joining and separating step 310 are included, and among these, the folded portion forming step 309 is a characteristic step as compared with the prior art.

  That is, in the elastic member attaching step 301, a belt-like sheet material 12S having a predetermined width is conveyed along the continuous direction, and the elastic expansion / contraction of thread rubber or the like is performed almost entirely at intervals in the CD direction of the sheet material 12S. The members 15 to 17 and 19 are fixed in a state of being stretched in the MD direction, and a belt-like sheet material 12H having a predetermined width is further supplied and bonded along the continuous direction on the upper surface to form an elastic band. In the illustrated example, it is assumed that two sheet materials 12S and 12H are bonded together and the elastic elastic members 15 to 17 and 19 are sandwiched. However, one sheet material is folded in half or C to be elastically expanded and contracted. A member can also be clamped. Further, at least one end portion in the CD direction of one sheet material can be folded back to the back side (opposite side of the facing surface) of the other sheet material.

  Next, an elastic member cutting step 302 is performed on the formed elastic bands 12f and 12b as necessary, and a predetermined interval is formed in the MD direction, and the elastic elastic member 15 located in a portion CT that overlaps the interior body 200 later. , 16, 19 are cut by a cutting device such as heat embossing so that the elastic force of the elastic elastic members 15, 16, 19 does not act on the portion CT.

  Next, in the exterior cutting and dividing step 304, a slitter cuts a predetermined portion SL in the middle of the CD direction in the elastic band along the MD direction, and divides it into a front elastic band 12f and a rear elastic band 12b, and the front elastic band 12f. And the space | interval of the rear side elastic band 12b is expanded to predetermined distance. In the illustrated example, the front elastic band 12f and the rear elastic band 12b are formed as an integral elastic band, and then divided separately in the cutting and dividing step 304. However, the front elastic band 12f and the rear elastic band 12b are separated from each other. By using a sheet material, the cutting and dividing step 304 can be omitted. In this case, two sheet materials are bonded to each other, and an elastic elastic member is sandwiched between them. The elastic elastic member can be clamped by folding it in half or C, or at least one end in the CD direction of one sheet material can be folded back to the back side (opposite the opposite surface) of the other sheet material.

  After this exterior cutting and dividing step 304, if necessary, at least one of the front elastic band 12f and the rear elastic band 12b is cut off at the center edge in the CD direction (the portion that becomes the edge Le of the leg opening) in a curved shape. A leg opening cutting step 305 is performed. In the illustrated embodiment, only the center edge in the CD direction of the rear elastic band 12b is cut off in a curved shape, but the front elastic band 12f can also be cut off, and if the trim loss is completely eliminated, a leg opening cutting step is performed. It can be omitted.

  Next, in the interior body attaching step 306, the front elastic band 12f and the rear elastic band 12b are transferred in parallel in the CD direction with an arrangement similar to the deployed state of the diaper while being separated by a known method on a separate line. The unfolded interior body 200 manufactured in parallel is supplied at a predetermined interval in the MD direction, the front side part of the interior body 200 is used as the front elastic band 12f, and the rear side part of the interior body 200 is used as the rear side. Each is joined to the elastic band 12b to form an interior assembly in which a portion that becomes an individual diaper is continuous in the MD direction in a developed state. These joining and fixing can be performed by appropriate means such as a hot melt adhesive or heat sealing.

  Next, after performing an exterior folding step 307 for folding the outer ends of the front elastic band 12f and the rear elastic band 12b in the CD direction to the interior body 200 as necessary, in the folding process 308, the interior in the front elastic band 12f is performed. The interior assembly is folded in half at the center in the CD direction so that the attachment surface of the body 200 and the attachment surface of the interior body 200 in the rear elastic band 12b overlap to form a foldable belt-like body 90. Prior to the folding step 308, if necessary, at least a part of the inner surface on the front body F side and the inner surface on the rear body B side facing each other is releasably joined by the joining means 80b, and the temporary fixing portion 80 is attached. Can be provided.

  Next, in a folded portion forming step 309, a folded portion 70 is formed by folding a portion including the double fold in the folded band 90 between the front body F side and the back body B side. Although the formation method of the folding part 70 is not specifically limited, for example, as shown in FIG. 13, the pair of front and rear upper guide bars 101 and 102 are placed at the lower end of the folding part 70 between the two folded strips 90. A lower guide bar 103 that passes linearly along the MD direction and that rises above the upper guide bars 101 and 102 toward the downstream side in the MD direction is disposed below the folded portion of the bifold strip 90. When the bi-fold band 90 passes through the upper guide bars 101, 102 and the lower guide bar 103, the portion including the bi-fold fold in the bi-fold band 90 contacts the lower guide bar 103, and the front body F side and A fold-in part 70 is formed by being pushed between the parts on the rear body B side. In addition, the vertical direction expression in this description is based on the vertical direction when the diaper is mounted, and is not based on the vertical direction of the equipment.

  Thereafter, in the side joining and detaching step 310, the front elastic band 12f and the rear elastic band 12b are bonded to each side part of the diaper to form the side seal part 12A, and the front elastic band 12f. And the back side elastic band 12b is cut | disconnected in the boundary of each diaper, and each diaper DP is obtained. It is included in the present invention that the side joining step and the separation step are performed sequentially or simultaneously. According to this manufacturing method, the underpants type disposable diaper which has the folding part 70 can be manufactured by a simple change which only adds the folding part 70 formation process with respect to the conventional manufacturing method.

  On the other hand, in the case of manufacturing a pants-type disposable diaper having an integrated exterior body that continues from the abdominal side to the back side through the crotch, the leg is cut in the leg opening cutting step 305 without performing the exterior cutting division step 304. It is only necessary to punch out the opening.

<Sensory evaluation>
A commercially available product (comparative example) having no folded portion shown in Table 1 and a sample (example) in which a folded portion is formed in the same manner as the forms shown in FIGS. We evaluated which was superior in carrying characteristics. The evaluation was performed by confirming portability by actually touching the appearance. As a result, 86% of the respondents answered that the sample of the example had better portability. In addition, the product vertical dimension in the table means the length in the vertical direction from the edge of the waist opening to the crotch side edge in the product state in which the side seal part is joined, and the vertical dimension reduction rate is the state without folding. It means the ratio of the product vertical dimension in the folded state to the product vertical dimension.

<Explanation of terms in the specification>
The following terms in the specification have the following meanings unless otherwise specified in the specification.
The “front / rear (vertical) direction” means a direction connecting the ventral side (front side) and the back side (rear side), and the “width direction” means a direction (left / right direction) orthogonal to the front / rear direction.

  “Elongation rate” means a value when the natural length is 100%.

  -"Gel strength" is measured as follows. 49.0 g of artificial urine (urea: 20 wt%, salt: 8 wt%, calcium chloride dihydrate: 0.3 wt%, magnesium oxide heptahydrate: 0.8 wt%, pure water: 70.01 wt%), Add 1.0 g of superabsorbent polymer and stir with a stirrer. The produced gel is left in a constant temperature and humidity chamber of 40 ° C. × 60% RH for 3 hours and then returned to room temperature, and the gel strength is measured with a card meter (Curdmeter-MAX ME-500, manufactured by I.techno Engineering).

  ・ "Weight" is measured as follows. After the sample or test piece has been pre-dried, it is left in a test room or apparatus in a standard state (test location is temperature 20 ± 5 ° C., relative humidity 65% or less) to obtain a constant weight. Pre-drying refers to making a sample or test piece constant in an environment where the relative humidity is 10 to 25% and the temperature does not exceed 50 ° C. In addition, it is not necessary to perform preliminary drying about the fiber whose official moisture content is 0.0%. A sample with a size of 200 mm × 250 mm (± 2 mm) is cut out from the test piece in a constant weight using a rice-basis plate (200 mm × 250 mm, ± 2 mm). Measure the weight of the sample, multiply it by 20, calculate the weight per square meter, and use it as the basis weight.

- "thickness" is used automatic thickness measuring instrument (KES-G5 Handy Compression measurement program), load: 10 gf / cm ^2, and the pressure area: automatically measured under the conditions of 2 cm ^2.

  -The amount of water absorption is measured according to JIS K7223-1996 "Test method for water absorption of superabsorbent resin".

  ・ The water absorption rate is the “time to end point” when JIS K7224-1996 “Test method for water absorption rate of superabsorbent resin” is performed using 2 g of superabsorbent polymer and 50 g of physiological saline. .

  The present invention can be used for a pants-type disposable diaper as in the above example.

  DESCRIPTION OF SYMBOLS 11 ... Liquid impermeable sheet | seat, 12F, 12B ... Exterior body, 12A ... Side seal part, 12r ... Folded part, 200 ... Interior body, 30 ... Top sheet, 40 ... Intermediate sheet, 50 ... Absorbing element, 56 ... Absorber 58 ... packaging sheet, 60 ... solid gather, 62 ... gather sheet, 12F ... front exterior body, 12B ... rear exterior body, F ... front body, B ... back body, T ... first region, L ... second region , 14 ... buttocks cover part, 70 ... folding part, 70d ... folding depth, 70e ... folding edge, WO ... waist opening, LO ... leg opening, W ... waist edge part, 80 ... temporary fixing part, 90 ... two-fold band shape 301, elastic member attaching step, 302 ... elastic member cutting step, 304 ... exterior cutting and dividing step, 305 ... leg opening cutting step, 306 ... interior body attaching step, 307 ... exterior folding step, 308 ... folding See step 309 ... folding portion forming step, 310 ... side bonding and disconnecting step.

Claims (5)

The waist opening and the leg opening are formed by joining the both sides of the front body and the both sides of the back body to form the side seal part,
A first region defined as a front-rear direction range having a side seal portion, and a second region defined as a front-rear direction range of a portion forming a leg opening,
At least the front-rear direction intermediate part of the second region is folded between the front and rear side parts to form a folded part,
A pants-type disposable diaper characterized by that.   The pants-type disposable diaper according to claim 1, wherein at least a part of the opposing surface of the folded portion is releasably joined.   The pants-type disposable diaper according to claim 1 or 2, wherein a folded edge of a facing surface of the folded portion is located in the second region.   The pants-type disposable diaper according to claim 1 or 2, wherein a folded edge of an opposing surface of the folded portion is located in the first region. An interior body that individually or integrally configures the front body and the back body, and an interior of the excrement absorber provided inside the exterior body so as to extend from the front body to the back body through the crotch. The pants type has a waist opening and a leg opening formed by joining the both sides of the exterior body of the front body and the both sides of the exterior body of the back body to form a side seal part. In the manufacturing method of disposable diapers,
Forming an exterior belt-like body that repeats and continues in the MD direction so that the width direction and the MD direction of the portion to be the exterior body coincide with each other;
While the outer band is transported so that the width direction of the diaper is the MD direction in the same arrangement as the unfolded state of the diaper, a separately manufactured unfolded portion is provided on each of the outer band bodies as the individual outer body. An inner body attachment step in which the inner layer assembly is formed by sequentially joining the inner bodies in a state to form an inner layer assembly in which the portions serving as diapers are continuous in the MD direction in a deployed state;
A folding step in which the inner layer assembly is folded in the CD direction to form a folded band-like body;
A folded portion forming step of forming a folded portion by folding a portion including a bifold fold in the bifold band-like body between the front body side portion and the back body side portion;
Joining the outer body of the front body and the outer body of the back body at the parts that will be both sides of each diaper, cutting the outer body of the front body and the back body of the front body at the boundary of each diaper, Obtaining a diaper, side joining and disconnecting step;
A method for producing a pants-type disposable diaper, comprising:

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