JP5980399B1 - Pants-type disposable diaper - Google Patents

Abstract

An absorbent article having a simple structure and improved fit to a crotch portion and a base of a leg is provided. A narrow portion narrower than the front and rear sides is formed in a crotch portion of an absorbent body, and both side portions corresponding to the narrow portion of the absorbent body serve as a non-absorbent body side portion having no absorbent body. Reference numeral 10 denotes a width extending from one non-absorbent body side to the other non-absorbent body side, and is fixed to the exterior body 20 in the inner and outer fixing regions extending from the front and rear sides of the non-absorbent body side section, and rises from both side edges of the interior body to the skin side. An elastic film in which three-dimensional gathers are provided on both the front and rear sides of the non-absorbent body side, and the outer body of the front body F is laminated with an elastic film from the front-rear direction range corresponding to the narrowest portion 13m of the constricted portion to the waist portion. The elastic film elastic structure region has an elastic region 20X, and has an elastic region 80 that contracts in the width direction due to the elastic film contraction and can be expanded in the width direction. The containing portion 10c fixed to the outer body. [Selection] Figure 2

Description

  The present invention relates to a pants-type disposable diaper.

  The pants-type disposable diaper includes an exterior body that individually or integrally configures the front body and the back body, and an interior body including an absorbent body that is attached to the inner surface of the exterior body so as to extend from the front body to the back body. Generally, a waist opening and a pair of left and right leg openings are formed by joining the side edges of the outer body of the front body and the side edges of the outer body of the rear body to form a side seal part. Is.

  The outer body of the pants-type disposable diaper is provided with elastic members such as rubber thread in the waist area that is defined as the front-rear direction range (the front-rear direction range from the waist opening to the upper end of the leg opening) with side seals. (For example, refer to Patent Documents 1 and 2). As an elastic member for that purpose, a number of conventional elastic members such as rubber thread are elongated in the longitudinal direction. Although the method of fixing in a line is widely adopted, a method of attaching an elastic film in a stretched direction in a stretchable direction has been proposed as an excellent surface fit. (For example, refer to Patent Document 1).

  The elastic film stretchable structure (hereinafter also referred to as an elastic film stretchable structure) is formed by laminating an elastic film between a first sheet layer made of a nonwoven fabric and a second sheet layer made of a nonwoven fabric, In a state where the elastic film is stretched in the stretching direction along the surface thereof, the first sheet layer and the second sheet layer are arranged in a number of dotted shapes arranged at intervals in the stretching direction and the direction orthogonal thereto. In the sheet joining portion, the sheet is joined through a through hole formed in the elastic film. Such an elastic film stretchable structure is such that, in the natural length state, as the elastic film contracts between the sheet joining portions, the interval between the sheet joining portions becomes narrow, and the sheet joining portions in the first sheet layer and the second sheet layer A contraction fold extending in the direction intersecting the expansion / contraction direction is formed therebetween. On the other hand, when the elastic film is stretched between the sheet joining portions at the time of stretching, the spacing between the sheet joining portions and the shrinkage wrinkles in the first sheet layer and the second sheet layer spread, and the first sheet layer and the second sheet layer Elastic extension is possible up to the fully deployed state. This elastic film stretchable structure is excellent in surface fit, and there is no bonding between the first sheet layer and the second sheet layer and the elastic film, and the first sheet layer and the second sheet layer are extremely bonded. Since there are few, it is very flexible, and there exists an advantage that the through-hole of an elastic film contributes also to air permeability improvement.

  The elastic film stretchable structure cannot be arranged in a curved line like the conventional stretchable structure of an elongated elastic member. For this reason, in a pants-type disposable diaper, in order to add stretchability in the width direction to the waist area, and to improve the fit to the base of the leg in the crotch part and its front and back, a curve along the edge around the leg It has been proposed to provide an elongated elastic member in a shape (see Patent Document 2). However, in this case, an elastic sheet having an elastic film elastic structure and an elastic sheet in which an elongated elastic member is attached in a curved shape are separately manufactured and assembled. It is also a problem that the portion to be bonded becomes thick and hard.

JP-T-2004-532758 Special table 2009-536845 JP 2011-136095 A Japanese Patent No. 5250372

  Therefore, the main problem of the present invention is that the pants-type disposable diaper has an elastic film expansion / contraction structure that adds stretchability in the width direction to the waistline portion, and has a simple structure and fits to the crotch portion and the base of the leg in the vicinity of the front and back. It is to improve the performance.

The present invention that has solved the above problems is as follows.
<Invention of Claim 1>
An exterior body that individually or integrally configures the front body and the back body, and an interior body including an absorber attached to the exterior body so as to reach the back body from the front body through the crotch part,
A waist opening and a pair of left and right leg openings are formed by joining the side edge portions of the exterior body in the front body and the side edge portions of the exterior body in the back body to form a side seal portion. ,
In pants-type disposable diapers,
In the crotch portion of the absorbent body, a narrowed portion narrower than both front and rear sides is formed, and both side portions of the interior body corresponding to the narrowed portion of the absorbent body have no absorbent body. And
The exterior body extends laterally from a side edge of the absorber,
The interior body is fixed to the exterior body in a width extending from one non-absorbent body side to the other non-absorbent body side, and in the inner and outer fixing regions extending from the front and rear sides of the non-absorbent body side,
A three-dimensional gather that stands on the skin side of the wearer from both side edges of the interior body is provided over both front and rear sides of the non-absorbent body side,
The exterior body has a first sheet layer extending from the front-rear direction range corresponding to the narrowest portion of the constricted portion to the front-rear direction range corresponding to the side seal portion in at least one of the front body and the rear body. In addition, an elastic film is laminated between the second sheet layer, and the first sheet layer and the second sheet layer are directly or indirectly joined at a plurality of sheet joint portions arranged at intervals. , Has an elastic film stretchable structure,
The region having the elastic film stretchable structure in the exterior body has a stretchable region that is shrinkable in the width direction due to the shrinkage of the elastic film, and is stretchable in the width direction,
This stretchable region includes a portion for fixing at least the non-absorbent side of the inner and outer fixed region to the exterior body,
The exterior body does not have an elongated elastic elastic member extending along the leg opening,
A pants-type disposable diaper characterized by that.

(Function and effect)
In the present invention, since the non-absorbent body side portion of the interior body is fixed to the stretchable region of the exterior body, the non-absorbent body side portion of the interior body contracts to the center in the width direction due to the shrinkage of the stretchable region of the exterior body. Accordingly, the rising position of the three-dimensional gather moves to the center in the width direction and rises from a position closer to the side edge of the constricted portion of the absorber, i.e., a position suitable for the width of the wearer's crotch. The fit to the root is improved and the leakage prevention property is high. And since it does not have the elongate elastic expansion-contraction member extended along leg opening, a structure is simple and a softness | flexibility is not impaired.

<Invention of Claim 2>
The outer body of the front body has the elastic film stretchable structure from the front-rear direction range corresponding to the narrowest part of the constricted part to the front-rear direction range corresponding to the side seal part, and its elasticity The pants-type disposable diaper according to claim 1, wherein a region overlapping with the inner and outer fixed regions among the regions having a film stretchable structure is a weak stretchable region having a shorter elastic limit elongation than a region located on the side thereof.

(Function and effect)
By providing such a weakly stretchable region, not only the fit to the base of the leg in the crotch and its front and back, but also the fit of the front body to the body part from the lower abdomen to the crotch, and the back from the buttocks to the crotch The body fit is also good. In particular, the weak stretch region of the elastic film stretch structure of the front body suppresses the expansion of the front absorbent body during urination (generally the front side is easier to expand than the rear side), and maintains the appearance like underwear it can.

<Invention of Claim 3>
The outer body of the rear body has the elastic film stretchable structure over the front-rear direction range corresponding to the side seal portion and the front-rear direction range, and the inner and outer sides of the region having the elastic film stretchable structure. The pants-type disposable diaper according to claim 2, wherein a region overlapping with the fixed region is a non-stretchable region.

(Function and effect)
By adopting such a front-rear asymmetric structure, not only the fit to the crotch and the base of the leg in the vicinity of the crotch, but also the fit of the front body to the body part from the lower abdomen to the crotch, and the swelling of the crotch to the buttocks The fit of the back body is also good. In addition, as described above, the weak stretch region of the elastic film stretch structure of the front body suppresses the expansion of the front absorbent body during urination (generally the front side is easier to expand than the rear side), and looks like underwear Can be maintained.

<Invention of Claim 4>
Each of the front body and the back body has an elastic film stretchable structure, and the elastic film constituting the elastic film stretchable structure of the front body and the elastic film constituting the elastic film stretchable structure of the back body are separated front and back And separated in the front-rear direction,
The underpants type disposable of Claim 2 or 3 by which the rear end of the elastic film which comprises the elastic film elastic structure of the said front body is located in the range from the front-back direction center of a pants type disposable diaper to 60 mm to the front side. Diapers.

(Function and effect)
By attaching the elastic film separately in the front body and the back body, the front-rear direction dimension of the elastic film attached to the exterior body can be shortened, and the manufacture becomes easy.

<Invention of Claim 5>
The stretchable region in the elastic film stretchable structure provided from the front-rear direction range corresponding to the narrowest portion of the constricted portion to the front-rear direction range corresponding to the side seal portion is from the side seal portion to the The edge area | region of the leg opening to the side edge of the area | region which overlaps with a non-absorbent body side part has the weak extension stress of the width direction rather than the part adjacent to the waist side, The any one of Claims 1-4. Pants-type disposable diaper.

(Function and effect)
By configuring in this way, the feel of the edge region of the leg opening becomes flexible in a similar manner from the side seal portion to the region overlapping the non-absorbent side, and there is a sense of incongruity due to contraction of only the non-absorbent side in the width direction. It is reduced.

  As described above, according to the present invention, in the pants-type disposable diaper in which the stretchable portion in the width direction is added to the waist portion by the elastic film stretchable structure, with a simple structure, the crotch portion and the base of the leg in the vicinity of the front and back are provided. Advantages such as being able to improve fit are provided.

It is a top view (inner surface side) of the underpants type disposable diaper of a deployment state. It is a top view (outer surface side) of the underpants type disposable diaper of a deployment state. It is a top view which shows only the principal part of the underpants type disposable diaper of an unfolded state. (A) is CC sectional drawing of FIG. 1, (b) is EE sectional drawing of FIG. It is AA sectional drawing of FIG. It is BB sectional drawing of FIG. (A) is a principal part top view of an expansion-contraction area | region, (b) is DD sectional drawing of (a), (c) is sectional drawing in a mounting state, (d) is sectional drawing in a natural length state. It is the (a) microscope picture from a plane direction of the expansion-contraction area | region of a sample, (b) the high magnification microscope picture from a plane direction, (c) The high magnification microscope picture from a perspective direction. (A) is a principal part top view of an expansion-contraction area | region, (b) is DD sectional drawing of (a), (c) is sectional drawing in a mounting state, (d) is sectional drawing in a natural length state. It is the (a) microscope picture from a plane direction of the expansion-contraction area | region of a sample, (b) the high magnification microscope picture from a plane direction, (c) The high magnification microscope picture from a perspective direction. (A) is a principal part top view of a non-expandable area | region, (b) is DD sectional drawing of (a), (c) is sectional drawing in a mounting state, (d) is sectional drawing in a natural length state. It is a photograph of the non-stretchable region of the sample. It is a principal part enlarged plan view of a non-expandable region. It is a crotch part sectional drawing which shows the principal part of a mounting state schematically. It is a top view (outer surface side) of the underpants type disposable diaper of a deployment state. (A) is CC sectional drawing of FIG. 15, (b) is EE sectional drawing of FIG. It is sectional drawing which shows roughly the principal part cross section of the exterior body extended to some extent. It is sectional drawing which shows roughly the principal part cross section of the exterior body extended to some extent. (A) The plane photograph of the sheet | seat junction part formed with the 1st welding form, (b) The plane photograph of the sheet | seat junction part formed with the 3rd welding form. It is the schematic of an ultrasonic sealing apparatus. It is a top view which shows the various arrangement | sequence examples of a sheet | seat junction part.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings. In addition, the dotted pattern part in sectional drawing has shown joining means, such as a hot-melt-adhesive.
1 to 6 show a pants-type disposable diaper. This pants-type disposable diaper (hereinafter also simply referred to as a diaper) has an exterior body 20 that forms a front body F and a back body B, and an interior body 10 that is fixed to and integrated with the inner surface of the exterior body 20. The interior body 10 has an absorbent body 13 interposed between a liquid-permeable top sheet 11 and a liquid-impermeable sheet 12. In manufacturing, after the back surface of the interior body 10 is joined to the inner surface (upper surface) of the exterior body 20 by a joining means such as a hot melt adhesive, the interior body 10 and the exterior body 20 are the front body F and the back body B. Are folded at the center in the front-rear direction (longitudinal direction), and the side seal portions 21 are formed by joining both sides thereof by heat welding or hot melt adhesive, thereby forming a waist opening and a pair of left and right A pants-type disposable diaper with a leg opening.

(Structural example of interior body)
As shown in FIGS. 4 to 6, the interior body 10 has a structure in which an absorbent body 13 is interposed between a liquid-permeable top sheet 11 and a liquid-impermeable sheet 12 made of polyethylene or the like. In addition, the excretory fluid that has passed through the top sheet 11 is absorbed and held. Although the planar shape of the interior body 10 is not particularly limited, it is generally a rectangular shape as shown in FIG.

  As the liquid-permeable top sheet 11 covering the front side (skin side) of the absorbent body 13, a porous or non-porous nonwoven fabric or a porous plastic sheet is preferably used. The material fibers that make up the nonwoven fabric can be synthetic fibers such as polyethylene or polypropylene, synthetic fibers such as polyester or polyamide, recycled fibers such as rayon or cupra, natural fibers such as cotton, and the spunlace method. A nonwoven fabric obtained by an appropriate processing method such as a spun bond method, a thermal bond method, a melt blown method, or a needle punch method can be used. Among these processing methods, the spunlace method is excellent in terms of flexibility and drapeability, and the thermal bond method is excellent in terms of being bulky and soft. When a large number of through holes are formed in the liquid permeable top sheet 11, urine and the like are quickly absorbed, and the dry touch property is excellent. The liquid-permeable top sheet 11 is wound around the side edge of the absorber 13 and extends to the back side of the absorber 13.

  As the liquid-impermeable sheet 12 covering the back side (non-skin contact side) of the absorbent body 13, a liquid-impermeable plastic sheet such as polyethylene or polypropylene is used, but in recent years, it has moisture permeability from the viewpoint of preventing stuffiness. Are preferably used. This water-impervious and moisture-permeable sheet is a microporous sheet obtained by, for example, melt-kneading an inorganic filler in an olefin resin such as polyethylene or polypropylene to form a sheet, and then stretching in a uniaxial or biaxial direction. is there.

  Absorbent body 13 is a known one, for example, a pulp fiber stack, a filament aggregate such as cellulose acetate, or a non-woven fabric, mixed with a superabsorbent polymer as necessary, fixed, etc. Can be used. The absorbent body 13 can be packaged with a wrapping sheet 14 having liquid permeability and liquid retention, such as crepe paper, if necessary, for holding the shape and polymer.

  The shape of the absorber 13 is formed in a substantially hourglass shape having a narrowed portion 13N narrower than the front and rear sides at the crotch portion. Although the size of the constricted portion 13N can be determined as appropriate, the length in the front-rear direction of the constricted portion 13N can be about 20 to 50% of the total length of the diaper, and the width of the narrowest portion is 40% of the total width of the absorber 13. It can be about -60%. In the case of having such a constricted portion 13N, if the planar shape of the interior body 10 is substantially rectangular, the interior body 10 has no absorber 13 in a portion corresponding to the constricted portion 13N of the absorber 13. Absorber side portions 17 are formed.

  Solid gathers 90 that fit around the legs are formed on both sides of the interior body 10. As shown in FIGS. 5 and 6, the three-dimensional gather 90 includes a fixed portion 91 fixed to a side portion on the back surface of the interior body 10, and 10 interior bodies through the side of the interior body 10 from the fixed portion 91. A body portion 92 extending to the side of the surface of the body, a front-rear end portion of the body portion 92 in a lying state, and a lying portion 93 formed by being fixed to the side portion of the surface of the interior body. And a free portion 94 formed non-fixed. Each of these parts is formed of a gather sheet 95 which is a double sheet obtained by folding a sheet such as a nonwoven fabric. The gather sheet 95 is attached over the entire front-rear direction of the interior body 10, the lying portion 93 is provided on the front side and the rear side of the non-absorbent body side portion 17, and the free portion 94 is disposed on both front and rear sides of the non-absorbent body side portion 17. Has been extended.

  In addition, an elongated gather elastic member 96 is disposed between the double gather sheets 95 at the tip of the free part. As shown in FIG. 14, the gather elastic member 96 is for forming the three-dimensional gather 90 by raising the free portion 94 by elastic contraction force as shown in FIG. 14.

  The liquid-impermeable sheet 12 is folded back on the both sides in the width direction of the absorber 13 together with the liquid-permeable top sheet 11. As this liquid-impermeable sheet 12, it is desirable to use an opaque sheet so that brown color such as defecation and urine does not appear. As the opacification, a plastic film and a pigment and filler such as calcium carbonate, titanium oxide, zinc oxide, white carbon, clay, talc and barium sulfate are preferably used.

  As the gather elastic member 96, materials such as styrene rubber, olefin rubber, urethane rubber, ester rubber, polyurethane, polyethylene, polystyrene, styrene butadiene, silicon, polyester, and the like that are usually used can be used. In order to make it difficult to see from the outside, it is preferable that the thickness is 925 dtex or less, the tension is 150 to 350%, and the interval is 7.0 mm or less. As the gather elastic member 96, a tape-like member having a certain width can be used in addition to the thread-like shape shown in the figure.

  As with the liquid-permeable top sheet 11, the material fiber constituting the gather sheet 95 is made of synthetic fibers such as polyethylene or polypropylene such as olefin, polyester or amide, as well as recycled fibers such as rayon and cupra, and cotton. Non-woven fabric obtained by an appropriate processing method such as a spunbond method, a thermal bond method, a melt blown method, a needle punch method, etc. can be used. It is preferable to use a nonwoven fabric that suppresses the basis weight and has excellent air permeability. Furthermore, for the gather sheet 95, in order to prevent permeation of urine and the like, to prevent fogging and to improve the touch to the skin (dry feeling), silicon-based, paraffin metal-based, alkylchromic croid-based water repellent, etc. It is desirable to use a water-repellent non-woven fabric coated with.

  As shown in FIG. 3, the back surface of the interior body 10 is fixed to the inner surface of the exterior body 20 with a hot melt adhesive or the like in the inner / outer fixing area 10 </ b> B (shaded area). This inner / outer fixed region 10 </ b> B extends across the front and rear sides of the non-absorbent body side portion 17 with a width extending from one non-absorbent body side portion 17 to the other non-absorbent body side portion 17. The side edge of the inner / outer fixing region 10B is preferably located laterally from the middle in the width direction of the non-absorbent body side portion 17, and in particular, the exterior body over almost the whole width direction of the interior body 10 and almost the whole front and rear direction. More preferably, it is fixed to 20.

(External body structure example)
The exterior body 20 extends from the side edge of the absorber 13 to the side. As long as this is the case, the exterior body 20 is located in the crotch portion even if the side edge of the exterior body 20 is located on the center side in the width direction from the side edge of the interior body 10 or on the outer side in the width direction. Also good. Further, the exterior body 20 is a front-rear direction range between a waistline T corresponding to the side seal portion 21 and a front-rear range, a waistline T of the front body F, and a waistline T of the back body B. And an intermediate portion L. And in the exterior body 20 of the illustrated form, as shown in FIG. 2 and FIGS. 4 to 6 except for the middle in the front-rear direction of the intermediate portion L, between the first sheet layer 20A and the second sheet layer 20B. While the elastic film 30 is laminated, as shown in FIG. 7, the first sheet layer 20 </ b> A and the second sheet layer 20 </ b> B penetrate the elastic film 30 with a large number of sheet joint portions 40 arranged at intervals. It has the elastic film expansion-contraction structure 20X joined through the through-hole 31, and the expansion-contraction direction was made into the width direction. The first sheet layer 20 </ b> A and the second sheet layer 20 </ b> B may be indirectly joined through the elastic film 30 instead of through the through hole 31 of the elastic film 30. The planar shape of the exterior body 20 is formed by concave leg-around lines 29 so that both side edges of the intermediate portion L in the width direction form leg openings, respectively, and has a pseudo hourglass shape as a whole. The exterior body 20 may be divided into two parts in the front-rear direction so that both are separated in the front-rear direction at the crotch part.

  The form shown in FIGS. 1 and 2 is a form in which the elastic film stretchable structure 20X extends to the waist end region 23, but when the elastic film stretchable structure 20X is used for the waist end region 23, the waist end portion is used. If necessary, as shown in FIGS. 15 and 16, the waist end region 23 is not provided with the elastic film stretchable structure 20X as shown in FIGS. A telescopic structure 20 </ b> X by the member 24 can also be provided. However, an elongated elastic elastic member extending along the leg opening is not provided at the edge part of the leg opening in the exterior body 20. The waist elastic member 24 is an elongated elastic member such as a plurality of thread rubbers arranged at intervals in the front-rear direction, and gives an elastic force so as to tighten around the body torso. The waist elastic members 24 are not arranged substantially as a single bundle with a close interval, but with a spacing of about 3 to 8 mm so as to form a predetermined stretch zone, preferably three or more, preferably Five or more are arranged. The stretch rate at the time of fixing the waist elastic member 24 can be determined as appropriate, but can be about 230 to 320% in the case of a normal adult. For the waist elastic member 24, thread rubber is used in the illustrated example, but other elongated elastic members such as flat rubber may be used.

  As other forms, although not shown in the figure, the middle part L between the waist part T of the front body F and the waist part T of the back body B is not provided with an elastic film stretchable structure 20X. A stretchable structure 20X is continuously provided in the front-rear direction from the inside of the waist T of the F to the inside of the waist T of the back body B through the intermediate part L, or only one of the front body F and the back body B is elastic. It is also possible to provide a film stretchable structure 20X.

  Although the shape in the natural length state of each sheet | seat junction part 40 and the through-hole 31 can be determined suitably, a perfect circle (refer FIG. 7, FIG. 8), an ellipse, a triangle, a rectangle (refer FIG. 9-12). ), Rhombus (see FIG. 13B), etc., or convex lens shape (see FIG. 13A), concave lens shape (see FIG. 13C), star shape, cloud shape, etc. be able to. The dimensions of the individual sheet joints are not particularly limited, but the maximum length is preferably 0.5 to 3.0 mm, particularly preferably 0.7 to 1.1 mm, and the maximum width 40x is 0.1 to 3.0 mm. In particular, when the shape is long in the direction orthogonal to the expansion and contraction direction, the thickness is preferably 0.1 to 1.1 mm.

The size of each sheet bonding portion 40 may be determined as appropriate. However, if the size is too large, the hardness of the sheet bonding portion 40 has an effect on the touch. If the size is too small, the bonding area is small and the materials are sufficiently bonded to each other. Since it becomes impossible, it is preferable that the area of each sheet | seat junction part 40 shall be about 0.14-3.5 mm < ² > normally. The area of the opening of each through hole 31 may be equal to or greater than the sheet joint portion because the sheet joint portion is formed through the through hole 31, but is about 1 to 1.5 times the area of the sheet joint portion. It is preferable. In addition, the area of the opening of the through-hole 31 means a value in a state of being integrated with the first sheet layer 20A and the second sheet layer 20B, not in the state of the elastic film 30 alone, and in a natural length state. When the area of the opening 31 is not uniform in the thickness direction, such as when the elastic film 30 is different from the front and back, it means the minimum value.

  The planar arrangement of the sheet joint portion 40 and the through-holes 31 can be determined as appropriate, but a regularly repeated planar arrangement is preferable, and an oblique lattice shape as shown in FIG. Hexagonal lattice shape as shown (these are also called zigzag shapes), square lattice shape as shown in FIG. 21 (c), rectangular lattice shape as shown in FIG. 21 (d), as shown in FIG. 21 (e) Parallel body lattice (as shown in the figure, two groups are provided so that a large number of groups of parallel diagonal rows intersect each other), etc. (these are inclined at an angle of less than 90 degrees with respect to the expansion and contraction direction And a group of sheet joint portions 40 (group unit arrangement may be regular or irregular, and may be a pattern or a letter shape) is regularly repeated. You can also

  The first sheet layer 20 </ b> A and the second sheet layer 20 </ b> B in the sheet bonding portion 40 are bonded through the through-hole 31 formed in the elastic film 30. In this case, it is desirable that the elastic film 30 is not bonded at least except between the first sheet layer 20A and the second sheet layer 20B in the sheet bonding portion 40.

  The joining means of the first sheet layer 20A and the second sheet layer 20B in the sheet joining portion 40 is not particularly limited. For example, the joining of the first sheet layer 20A and the second sheet layer 20B in the joining portion 40 may be performed by a hot melt adhesive, or may be performed by a joining means such as heat sealing or ultrasonic sealing.

  When the first sheet layer 20 </ b> A and the second sheet layer 20 </ b> B are bonded through the through hole 31 in the sheet bonding portion 40, the form in which the sheet bonding portion 40 is formed by material welding is the first sheet layer 20 </ b> A in the sheet bonding portion 40. And a first welding form in which the first sheet layer 20A and the second sheet layer 20B are joined only by the majority or part of the molten solidified material 20m of at least one of the second sheet layer 20B (see FIG. 17A), The second welding mode in which the first sheet layer 20A and the second sheet layer 20B are joined by all or most of the elastic film 30 in the sheet joining portion 40 or only a part of the melt-solidified material 30m (see FIG. 17B). , And a third welding form in which both of these are combined (see FIG. 17 (c)), but the second and third welding forms are preferable. Particularly preferably, the first sheet layer is composed of a part of the melt-solidified material 20m of the first sheet layer 20A and the second sheet layer 20B and the whole or most of the melt-solidified material 30m of the elastic film 30 in the sheet joint portion 40. 20A and the second sheet layer 20B are joined together. In addition, in the 3rd welding form shown by FIG.19 (b), between the fiber fusion | melting solidified materials 20m of the 1st sheet layer 20A or the 2nd sheet layer 20B which are reflected in black, the elastic film 30 which is reflected in white In contrast to the melted and solidified material 30m, in the first welding form shown in FIG. 19A, the elastic film is melted and solidified between the fiber melted and solidified materials 20m of the first sheet layer 20A or the second sheet layer 20B. No object is seen (the white part is the boundary of the fiber melt-solidified product 20m and the irregular reflection of the fiber melt-solidified product 20m).

  As in the first adhesive form and the third adhesive form, the first sheet layer 20A and the second sheet 20A and the second sheet 20A and the second sheet layer 20B are used by using at least one of the first sheet layer 20A and the second sheet layer 20B as the adhesive. When joining the sheet layer 20B, it is preferable not to melt part of the first sheet layer 20A and the second sheet layer 20B because the sheet joining part 40 does not harden. Note that when the first sheet layer 20A and the second sheet layer 20B are non-woven fabrics, a part of the first sheet layer 20A and the second sheet layer 20B does not melt. The composite fiber contains not only the core but also the central part of the single component fiber), but the surrounding part (including not only the sheath but also the surface part of the single component fiber of the composite fiber) melts, The fibers do not melt at all, but the remaining fibers either completely melt or the core remains but the surrounding portion includes a molten form.

  When the first sheet layer 20A and the second sheet layer 20B are joined using the melt-solidified material 30m of the elastic film 30 as an adhesive as in the second welding form and the third welding form, the peel strength becomes high. In the second welding mode, the first sheet layer 20A and the second sheet layer 20B have a melting point that is higher than the melting point of the elastic film 30 and the heating temperature when forming the sheet joint 40. In addition, the elastic film 30 is sandwiched between the second sheet layers 20 </ b> B, the portion to be the sheet bonding portion 40 is pressurized and heated, and only the elastic film 30 is melted. On the other hand, in the third welding mode, the first sheet layer 20A and the second sheet layer 20B are between the first sheet layer 20A and the second sheet layer 20B under the condition that the melting point of at least one of the first sheet layer 20A and the second sheet layer 20B is higher than the melting point of the elastic film 30. It can be manufactured by sandwiching the elastic film 30, pressurizing and heating a portion to be the sheet bonding portion 40, and melting at least one of the first sheet layer 20 </ b> A and the second sheet layer 20 </ b> B and the elastic film 30. From such a viewpoint, the melting point of the elastic film 30 is preferably about 80 to 145 ° C., and the melting points of the first sheet layer 20A and the second sheet layer 20B are about 85 to 190 ° C., particularly about 150 to 190 ° C. The difference between the melting points of the first sheet layer 20A and the second sheet layer 20B and the melting point of the elastic film 30 is preferably about 60 to 90 ° C. Moreover, it is preferable that heating temperature shall be about 100-150 degreeC.

  In the second welding mode and the third welding mode, when the first sheet layer 20A and the second sheet layer 20B are non-woven fabrics, the melt-solidified product 30m of the elastic film 30 is a sheet joint portion as shown in FIG. 40 may penetrate between the fibers in the entire thickness direction of the first sheet layer 20A and the second sheet layer 20B, but as shown in FIGS. 17 (b) (c) and 18 (a), it is intermediate in the thickness direction. The form that penetrates between the fibers up to or the form that hardly penetrates between the fibers of the first sheet layer 20A and the second sheet layer 20B as shown in FIG. It will be a thing.

  FIG. 20 shows an example of an ultrasonic sealing device suitable for forming the second welding form and the third welding form. In this ultrasonic sealing apparatus, when the sheet bonding portion 40 is formed, the first sheet layer 20A, between the anvil roll 60 and the ultrasonic horn 61, each having a projection 60a formed in the pattern of the sheet bonding portion 40 on the outer surface, The elastic film 30 and the second sheet layer 20B are fed. At this time, for example, the feeding driving speed of the upstream elastic film 30 by the feeding driving roll 63 and the nip roll 62 is made slower than the feeding speed after the anvil roll 60 and the ultrasonic horn 61, thereby the feeding driving roll 63 and the nip roll 62. The elastic film 30 is stretched in the MD direction (machine direction, flow direction) to a predetermined stretch rate through the path from the nip position due to the above to the seal position due to the anvil roll 60 and the ultrasonic horn 61. The stretch rate of the elastic film 30 can be set by selecting the speed difference between the anvil roll 60 and the feed drive roll 63, and can be set to about 300% to 500%, for example. 62 is a nip roll. The first sheet layer 20 </ b> A, the elastic film 30, and the second sheet layer 20 </ b> B fed between the anvil roll 60 and the ultrasonic horn 61 are stacked in this order, and the protrusion 60 a and the ultrasonic horn 61 are While being pressurized, the ultrasonic horn 61 is heated by ultrasonic vibration energy to melt only the elastic film 30 or at least one of the first sheet layer 20A and the second sheet layer 20B and the elastic film 30 are melted. By doing so, the first sheet layer 20 </ b> A and the second sheet layer 20 </ b> B are joined through the through-hole 31 at the same time as the through-hole 31 is formed in the elastic film 30. Therefore, in this case, by selecting the size, shape, separation interval, arrangement pattern in the roll length direction and roll circumferential direction, etc., of the projections 60a of the anvil roll 60, the area ratio of the sheet joining portion 40 is selected. Can do.

  The reason why the through hole 31 is formed is not necessarily clear, but it is considered that the hole corresponding to the protrusion 60a of the anvil roll 60 in the elastic film 30 is melted and separated from the surroundings. At this time, the portion of the elastic film 30 between the adjacent through holes 31 aligned in the expansion / contraction direction is expanded / contracted by the through holes 31 as shown in FIGS. 7A, 9A, and 11A. Since it is cut from both sides and loses the support on both sides in the contraction direction, the central side in the direction orthogonal to the expansion / contraction direction is balanced with the central side in the expansion / contraction direction within a range that can maintain continuity in the direction orthogonal to the contraction direction. The through hole 31 expands in the expansion / contraction direction. And when the sheet | seat junction part 40 is formed in the pattern in which the part which the elastic film 30 continues linearly along the expansion-contraction direction like the expansion-contraction area | region 80 mentioned later is shown to Fig.7 (a) and FIG.9 (a). Thus, when contracting to a natural length state by cutting into individual products, the length in the expansion / contraction direction of the enlarged portion of the through hole 31 creates a gap between the through hole 31 and the sheet joining portion 40. It will shrink until it runs out. On the other hand, when the sheet bonding portion 40 is formed in a pattern in which the elastic film 30 does not have a linearly continuous portion along the stretching direction as in a non-stretchable region 70 described later, as shown in FIG. Since it hardly shrinks when it is shrunk to a natural length state by cutting into a product or the like, a large gap is left between the through hole 31 and the sheet bonding portion 40.

The constituent material of the first sheet layer 20A and the second sheet layer 20B can be used without particular limitation as long as it is a sheet, but it is preferable to use a nonwoven fabric from the viewpoint of air permeability and flexibility. 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 12 to ²⁰ g / m ² . Moreover, a part or all of the first sheet layer 20A and the second sheet layer 20B may be a pair of layers in which one material is folded and faced. For example, as shown in the figure, in the waist end region 23, the constituent material located outside is the second sheet layer 20B, and the folded portion 20C that is folded back to the inner surface side at the waist opening edge is the first sheet layer 20A. In addition, the elastic film 30 is interposed therebetween, and in the other portions, the constituent material positioned inside is the first sheet layer 20A, and the constituent material positioned outside is the second sheet layer 20B, and the elastic film 30 is interposed therebetween. Can be interposed. Of course, the constituent material of the first sheet layer 20A and the constituent material of the second sheet layer 20B are individually provided over the entire front-rear direction, and the constituent material of the first sheet layer 20A and the second sheet layer are not folded back. The elastic film 30 can also be interposed between the constituent materials of 20B.

  The elastic film 30 is not particularly limited, and as long as it is a thermoplastic resin film having elasticity per se, a film having a large number of holes and slits for ventilation can also be used. . In particular, the tensile strength in the width direction (stretching direction, MD direction) is 8 to 25 N / 35 mm, the tensile strength in the front-rear direction (direction perpendicular to the stretching direction, CD direction) is 5 to 20 N / 35 mm, and the tensile elongation in the width direction. Is preferably 450 to 1050%, and the elastic film 30 having a tensile elongation in the front-rear direction of 450 to 1400%. Although the thickness of the elastic film 30 is not specifically limited, It is preferable that it is about 20-40 micrometers.

(Elastic area)
The area | region which has the elastic film expansion-contraction structure 20X in the exterior body 20 has an expansion-contraction area | region which can be expanded-contracted in the width direction. In the stretchable region 80, the elastic film 30 has a portion 32 linearly continuous along the width direction, and is contracted in the width direction by the contraction force of the elastic film 30, and can be expanded in the width direction. It has become. More specifically, in a state where the elastic film 30 is extended in the width direction, the through-holes 31 of the elastic film 30 are formed at intervals in the width direction and in the front-rear direction (direction orthogonal to the expansion / contraction direction) orthogonal thereto. The first sheet layer 20 </ b> A and the second sheet layer 20 </ b> B are joined to each other to form a large number of sheet joint portions 40, thereby forming the elastic film stretchable structure 20 </ b> X. In the stretchable region 80, the elastic film 30 extends in the width direction. Such stretchability can be imparted by arranging the through holes 31 so as to have linearly continuous portions.

  In the stretchable region 80, in the natural length state, as shown in FIGS. 7D and 9D, the first sheet layer 20A and the second sheet layer 20B between the sheet joining portions 40 swell in a direction away from each other. Thus, as shown in FIGS. 7 (c) and 9 (c), a shrinking fold 25 extending in the width direction is formed, but the shrinking fold 25 is stretched but remains, as shown in FIGS. 7 (c) and 9 (c). It has become. Further, as illustrated, the first sheet layer 20A and the second sheet layer 20B are not joined to the elastic film 30 except at least between the first sheet layer 20A and the second sheet layer 20B in the sheet joining portion 40. FIGS. 7 (c) and 9 (d) assuming the mounted state, and FIGS. 7 (a) (b) and 9 (a) (9) assuming the expanded state of the first sheet layer 20A and the second sheet layer 20B. As can be seen from b), in these states, a gap is formed between the through hole 31 in the elastic film 30 and the sheet joint portion 40, and the material of the elastic film 30 is a non-porous film or sheet. However, air permeability is added by this gap. Further, in the natural length state shown in FIG. 7D and FIG. 9D, the through hole 31 is squeezed due to the contraction of the elastic film 30, and almost no gap is formed between the through hole 31 and the sheet joining portion 40. Not. In addition, the state of the shrinkage wrinkle 25 in the mounted state and the natural length state also appears in the sample photographs of FIGS.

  The elastic limit elongation in the width direction of the stretchable region 80 is desirably 200% or more (preferably 265 to 295%). The elastic limit elongation of the stretchable region 80 is substantially determined by the stretch rate of the elastic film 30 at the time of manufacture, but based on this, it is lowered by a factor that inhibits shrinkage in the width direction. The main factor of such inhibition is the ratio of the length 40x of the sheet joint portion 40 per unit length in the width direction, and the elastic limit elongation decreases as the ratio increases. In a normal case, the length 40x of the sheet bonding portion 40 has a correlation with the area ratio of the sheet bonding portion 40, so that the elastic limit elongation of the stretchable region 80 can be adjusted by the area ratio of the sheet bonding portion 40.

  The elongation stress of the stretchable region 80 can be adjusted mainly by the sum of the widths 32w of the portions 32 where the elastic film 30 continues linearly along the width direction. The width 32w of the portion 32 in which the elastic film 30 is linearly continuous along the width direction is equal to the interval 31d in the front-rear direction of the through-holes 31 in contact with both side edges of the continuous portion 32. 31d is when the length 31y of the through-hole 31 in the front-rear direction is equal to the length 40y of the sheet-joint portion 40 in the front-rear direction (when the above-described simultaneous formation method of the through-hole 31 and the sheet joint 40 is employed, etc.) ) Is equal to the interval 40d in the front-rear direction of the sheet joining portion 40 in contact with both side edges of the continuous portion. Therefore, in this case, the extension stress of the stretchable region 80 can be adjusted by the ratio of the length 40y of the sheet joint portion 40 per unit length in the front-rear direction. Since the length 40y has a correlation with the area ratio of the sheet bonding portion 40, the elongation stress of the stretchable region 80 can be adjusted by adjusting the length of the sheet bonding portion 40 by the area ratio of the sheet bonding portion 40. The elongation stress of the expansion / contraction region 80 can be determined based on the elongation stress when it is expanded to 50% of the elastic limit.

The area ratio of the sheet bonding portion 40 and the area of each sheet bonding portion 40 in the stretchable region 80 can be determined as appropriate, but in the normal case, it is preferably within the following range.
Area of sheet joint 40: 0.14 to 3.5 mm ² (particularly 0.14 to 1.0 mm ² )
Area ratio of sheet joint portion 40: 1.8 to 19.1% (particularly 1.8 to 10.6%)

  As described above, since the elastic limit elongation and the extension stress of the stretchable region 80 can be adjusted by the area of the sheet joint portion 40, a plurality of regions having different area ratios of the sheet joint portion 40 in the stretchable region 80 as shown in FIG. The fitting property can be changed according to the part. In the form shown in FIG. 15, the area 81 extending in the oblique direction along the base of the leg in the front body F and the edge area 82 of the leg opening have a higher area ratio of the sheet joint portion 40 than the other areas. Therefore, the extensional stress is weak and the region expands and contracts flexibly. In addition, the iliac facing region 83 and the edge region 82 of the leg opening in the back body B also have a higher area ratio of the sheet joint portion 40 than the other regions, and therefore the extension stress is weak and the region expands and contracts flexibly. It has become.

(Non-stretchable area)
As shown in FIG. 15, a non-stretchable region 70 can be provided on at least one side in the width direction of the stretchable region 80 in the region having the elastic film stretchable structure 20 </ b> X in the exterior body 20. The arrangement of the stretchable region 80 and the non-stretchable region 70 can be determined as appropriate. In the case of the exterior body 20 of the pants-type disposable diaper as in the present embodiment, the portion overlapping the absorber 13 is an area that does not need to be expanded and contracted, and therefore, part or all of the portion overlapping the absorber 13 as illustrated. It is preferable to make the non-stretchable region 70 (desirably including almost the entire inner and outer fixed region 10B). Of course, the non-stretchable region 70 can be provided from the region overlapping with the absorber 13 to the region not overlapping with the absorber 13 positioned in the width direction or the front-rear direction, and the non-stretchable region 70 is provided only in the region not overlapping with the absorber 13. It can also be provided.

  Although the elastic film 30 continues in the width direction, the non-stretchable region 70 is a region that does not have a linearly continuous portion along the width direction due to the presence of the through hole 31. Therefore, in a state where the elastic film 30 is extended in the width direction, the first sheet layer 20 </ b> A and the second sheet layer are spaced via the through-holes 31 of the elastic film 30 with an interval in the width direction and the front-rear direction orthogonal thereto. Even if the elastic film stretchable structure 20X including both the stretchable region 80 and the non-stretchable region 70 is formed by joining 20B and forming a large number of sheet joint portions 40, as shown in FIG. In the region 70, since the elastic film 30 does not continue linearly along the width direction, the contraction force of the elastic film 30 hardly acts on the first sheet layer 20A and the second sheet layer 20B, and the stretchability is almost lost. The elastic limit elongation is close to 100%. In such a non-stretchable region 70, the first sheet layer 20 </ b> A and the second sheet layer 20 </ b> B are joined by a large number of sheet joining portions 40 arranged at intervals, and the sheet joining portion 40 is not continuous. Therefore, a decrease in flexibility is prevented. In other words, the stretchable region 80 and the non-stretchable region 70 can be formed by the presence or absence of a portion where the elastic film 30 does not continue linearly along the width direction. Further, the continuity of the elastic film 30 remains even in the non-stretchable region 70, and as can be seen from the sample photograph shown in FIG. 12, the independent cut piece of the elastic film 30 does not remain and no wrinkles are formed. The appearance is very good and the air permeability in the thickness direction by the through hole 31 is ensured. The non-stretchable region 70 preferably has an elastic limit elongation in the width direction of 120% or less (preferably 110% or less, more preferably 100%).

  Although the arrangement pattern of the through holes 31 in the elastic film 30 in the non-stretchable region 70 can be determined as appropriate, it is arranged in a staggered manner as shown in FIG. When the pattern is shorter than the length 31y in the direction, the linear continuity in the width direction can be almost completely eliminated while maintaining the continuity of the elastic film 30, and the appearance is also preferable as shown in FIG. In this case, it is more preferable that the center interval 31f in the width direction of the through hole 31 is shorter than the length 31x of the through hole 31 in the width direction.

  Normally, when the elastic film 30 is stretched 4 times in the width direction and the extension stress is 4 to 12 N / 35 mm, the non-stretchable region 70 is stretched to the elastic limit in the width direction. The center distance 31e in the front-rear direction of the holes 31 is 0.4 to 2.7 mm, and the length 31y in the front-rear direction of the through holes 31 is 0.5 to 3.0 mm, particularly 0.7 to 1.1 mm. . Further, the center interval 31f in the width direction of the through hole 31 is preferably 0.5 to 2 times, particularly 1 to 1.2 times the length 31y of the through hole 31 in the front-rear direction. Is preferably 1.1 to 1.8 times, particularly 1.1 to 1.4 times the center interval 31f in the width direction of the through hole 31. In the state in which the non-stretchable region 70 is extended to the elastic limit in the width direction (in other words, the first sheet layer 20A and the second sheet layer 20B are completely expanded), the center interval 31f in the width direction of the through hole 31 Is equal to the center interval 40f in the width direction of the sheet bonding portion 40, the center interval 31e in the front-rear direction of the through-hole 31 is equal to the center interval 40e in the front-rear direction of the sheet bonding portion 40, and the length 31y in the front-rear direction of the through-hole 31 Is equal to the length 40y in the front-rear direction of the sheet joint 40.

  In the non-stretchable region 70, the first sheet layer 20A and the second sheet layer 20B and the elastic film 30 are not joined except for the portion between the first sheet layer 20A and the second sheet layer 20B in the sheet joining portion 40, And when it has a gap formed by separating the peripheral edge of the through hole 31 of the elastic film 30 and the sheet bonding portion 40 on both sides in the width direction of the sheet bonding portion 40 in a natural length state, the material of the elastic film 30 is Even a non-porous film or sheet is preferable because air permeability is always added by this gap. In the case where the above-described simultaneous formation method of the through hole 31 and the sheet joint portion 40 is adopted, this state naturally occurs regardless of the shape or the like of the sheet joint portion 40.

  Although the shape in the natural length state of each sheet | seat junction part 40 and the through-hole 31 is not specifically limited, In order to eliminate the linear continuity of the width direction of the elastic film 30, it is desirable that an area is small from a softness | flexibility viewpoint. Since it is desirable to have a shape that is long in the front-rear direction, an ellipse that is long in the front-rear direction, a rectangle (see FIGS. 11 and 13D), a rhombus (see FIG. 13B), and a convex lens shape (see FIG. 13). (See (a)), and preferably a concave lens shape (see FIG. 13C). However, if the corner is an acute angle like a diamond, the elastic film 30 is easily broken. On the other hand, the convex lens shape is preferable because the welding of the sheet joining portion 40 is stable, and the concave lens shape is preferable in that the area can be further reduced.

Although the area ratio of the sheet joint portion 40 and the area of each sheet joint portion 40 in the non-stretchable region can be determined as appropriate, in the normal case, if within the following range, the area of each sheet joint portion 40 is small and the sheet It is preferable that the non-stretchable region 70 does not become hard because the area ratio of the joint portion 40 is low.
Area of sheet joint 40: 0.10 to 0.75 mm ² (particularly 0.10 to 0.35 mm ² )
Area ratio of sheet joint 40: 4 to 13% (especially 5 to 10%)

  As described above, the elastic limit elongation of the non-stretchable region 70 can be changed by the arrangement pattern of the through holes 31, the dimensions of the individual through holes 31, and the center interval. Therefore, although not shown, these can be made different at a plurality of locations in the stretchable region 80 or between the plurality of non-stretchable regions 70. For example, it is one preferable mode to make the elastic limit elongation in the non-stretchable region 70 of the front body F larger than the elastic limit elongation in the non-stretchable region 70 of the rear body B.

  Although the non-stretchable region 70 has a portion that is linearly continuous along the width direction like the stretchable region, the elastic limit elongation is remarkable because the area ratio of the sheet joint portion is higher than the stretchable region. It is also possible to adopt a form that kills other stretchability, such as a form that is 130% or less, a form that is cut at one place or a plurality of places in the width direction, such as a stretchable structure using a conventional rubber thread.

(Positional relationship to the non-absorbent side)
Characteristically, as shown in FIG. 2, from the front-rear direction range corresponding to the narrowest portion 13m of the constricted portion 13N of the absorbent body 13 in the outer body 20 of the front body F, to the waist portion T The elastic film expansion / contraction structure 20X has an elastic film expansion / contraction structure 20X. The expansion / contraction region 80 in the region having the elastic film expansion / contraction structure 20X is a portion 10c (diagonal line) for fixing at least the non-absorbent side 17 to the exterior body 20 in the internal / external fixing region 10B. Area). As a result, the non-absorbent body side portion 17 of the interior body 10 is fixed to the expansion / contraction region 80 of the exterior body 20, so that in the mounted state, not the state shown in FIG. 14A but the state shown in FIG. It will be in the state shown. That is, the non-absorbent body side portion 17 of the interior body 10 contracts to the center in the width direction due to the contraction of the expansion / contraction region 80 of the exterior body 20, and accordingly the rising position of the three-dimensional gather 90 is the center in the width direction as indicated by the white arrow. Since it moves to the side and rises from a position closer to the side edge of the constricted portion 13N of the absorbent body 13, that is, a position suitable for the wearer's crotch width, the fit to the crotch part and the base of the leg is improved. , Leakage prevention is high. And since it does not have the elongate elastic expansion-contraction member extended along leg opening, a structure is simple and a softness | flexibility is not impaired.

  In this case, it is preferable that the rear end 30b of the elastic film 30 constituting the elastic film expansion / contraction structure 20X of the front body F is positioned within a range of 60 mm from the front-rear direction center to the front side of the pants-type disposable diaper.

  Instead of or together with this, also in the exterior body 20 of the back body B, as shown in FIG. 2, the waistline from within the front-rear direction range corresponding to the narrowest portion of the constricted portion 13N of the absorbent body 13 The elastic film expansion / contraction structure 20X is provided in the portion T, and the expansion / contraction region 80 of the region having the elastic film expansion / contraction structure 20X is a portion for fixing at least the non-absorbent body side portion 17 to the exterior body 20 in the inner / outer fixing region 10B. 10c may be included. In this case, it is preferable that the front end 30f of the elastic film 30 constituting the elastic film expansion / contraction structure 20X of the back body B is located within a range of 60 mm from the front-rear direction center to the rear side of the pants-type disposable diaper. Of course, the outer body 20 of either the front body F or the back body B is elastic from the rear side to the body periphery T from the front-rear direction range corresponding to the narrowest part of the constricted part 13N of the absorbent body 13. It can also be set as the form which has the film expansion-contraction structure 20X.

  When the non-absorbent body side portion 17 of the interior body 10 is contracted by the stretchable region 80 of the exterior body 20, the stretchable region 80 may be provided only in a portion overlapping the non-absorbent body side portion 17 in the inside / outside fixing region 10B of the exterior body 20. However, as shown in FIG. 15, when the non-absorbent body side portion 17 of the interior body 10 is contracted in the width direction by the expansion / contraction region 80 of the elastic film expansion / contraction structure 20X of the front body F, the elastic film expansion / contraction structure of the front body F It is a preferable mode that the entire region overlapping the inner and outer fixed regions 10B in the region having 20X is the weakly stretchable region 84 whose elastic limit elongation is shorter than the region located on the side thereof. This improves the fit of the front body F to the body part from the lower abdomen to the crotch, as well as the fit to the crotch and the base of the leg in the vicinity of the crotch, and the expansion of the front absorbent body 13 during urination (In general, the front side is easier to expand than the rear side), and the appearance like underwear can be maintained.

  Further, when the non-absorbent body side portion 17 of the inner body 10 is contracted in the width direction by the expansion / contraction region 80 of the outer body 20 in the front body F, as shown in FIG. Of the regions having the stretchable structure 20X, the entire region (including the region overlapping the non-absorbent body side portion 17) that overlaps with the inner / outer fixed region 10B is preferably the non-stretchable region 70. As a result, the fit of the back body B from the crotch to the bulge of the buttocks as well as the fit to the crotch and the base of the leg in the vicinity of the crotch is improved.

  Further, since the region overlapping the non-absorbent side portion 17 in the exterior body 20 forms a part of the edge portion of the leg opening, as shown in FIG. 15, the side of the region overlapping the non-absorbent side portion 17 from the side seal portion 21 It is desirable that the edge region 82 of the leg opening to the edge is an expansion / contraction region where the extension stress in the width direction is weaker than the portion adjacent to the waist side. As a result, the feel of the edge region 82 of the leg opening becomes flexible in a similar manner from the side seal portion 21 to the region overlapping the non-absorbent side portion 17, and the uncomfortable feeling due to contraction of only the non-absorbent side portion 17 in the width direction is reduced. Is done.

(Front / rear holding sheet)
As shown in FIGS. 1 and 4, in order to cover the front and rear end portions of the interior body 10 attached on the inner surface of the exterior body 20 and to prevent leakage from the front and rear edges of the interior body 10, 50 and 60 may be provided. The illustrated embodiment will be described in more detail. The front presser sheet 50 extends in the width direction from the inner surface of the folded portion 20C of the waist end region 23 to the position overlapping the front end portion of the inner body 10 in the inner surface of the outer body 20 of the front body F. The rear presser sheet 60 extends in the width direction from the inner surface of the folded portion 20C of the waist end region 23 to the position overlapping the rear end portion of the inner body 10 in the inner surface of the outer body 20 of the back body B. It extends throughout. If a slight non-adhesive portion is provided over the entire width direction (or only the central portion) at the crotch side edges of the front and rear pressing sheets 50, 60, not only does the adhesive not protrude, but this portion is slightly removed from the top sheet. Can float and function as a leak-proof wall.

  If the front and rear pressing sheets 50 and 60 are attached separately as in the illustrated form, there is an advantage that the degree of freedom of material selection is increased, but there are also disadvantages such as an increase in materials and manufacturing processes. Therefore, the folded portion 20C formed by folding the exterior body 20 on the inner surface of the diaper can be extended to a portion overlapping the interior body 10 to form a portion equivalent to the above-described pressing sheets 50 and 60.

<Explanation of terms in the specification>
The following terms in the specification have the following meanings unless otherwise specified in the specification.
-"Front body" and "rear body" mean the front and rear portions of the pants-type disposable diaper in the front-rear direction center, respectively. Moreover, a crotch part means the front-back direction range containing the center of the front-back direction of a pants type disposable diaper, and when an absorber has a constriction part, it means the front-back direction range of the part which has the said constriction part.
-“Elastic limit elongation” means the elongation of the elastic limit in the expansion / contraction direction (in other words, the state in which the first sheet layer and the second sheet layer are completely expanded), and the length at the elastic limit is the natural length. It is expressed as a percentage when 100% is assumed.
The “area ratio” means the ratio of the target portion to the unit area, and the target portion (for example, the sheet joint portion 40, the stretchable region 80, the non-stretchable region 70, the main stretchable portion, the buffer stretchable portion) in the target region. The total area of the through holes 31 and the vent holes) is divided by the area of the target region and expressed as a percentage. In particular, the “area ratio” in the region having the stretchable structure extends to the elastic limit in the stretchable direction. It means the area ratio of the state. In a form in which a large number of target portions are provided at intervals, it is desirable to set the target region to a size that includes 10 or more target portions and obtain the area ratio.
“Elongation rate” means a value when the natural length is 100%.
・ "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" of the absorber is a thickness measuring instrument (Peacock, dial thickness gauge large type, model JB (measurement range 0 to 35 mm) or model K-4 (measurement range 0 to 50 mm)) manufactured by Ozaki Mfg. Co., Ltd. Measure the sample and the thickness meter horizontally.
- other than the above "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.
・ "Tensile strength" and "tensile elongation (breaking elongation)" are in accordance with JIS K7127: 1999 "Plastic-Test method for tensile properties-" except that the test piece is rectangular with a width of 35 mm and a length of 80 mm. The initial chuck interval (distance between marked lines) is 50 mm, and the tensile speed is 300 mm / min. As a tensile tester, for example, AOUTGRAPHAGS-G100N manufactured by SHIMADZU can be used.
・ "Elongation stress" means according to JIS K7127: 1999 "Plastics-Test method for tensile properties-" by a tensile test in which the initial chuck interval (distance between marked lines) is 50 mm and the tensile speed is 300 mm / min. This means the tensile stress (N / 35 mm) measured when stretching in the elastic region, and the degree of stretching can be appropriately determined depending on the test object. It is preferable that the test piece has a rectangular shape with a width of 35 mm and a length of 80 mm or more. However, when a test piece with a width of 35 mm cannot be cut out, the test piece is prepared with a width that can be cut out, and the measured value is 35 mm. The value converted to. Even if the target area is small and sufficient specimens cannot be collected, as long as the magnitude of the extension stress is compared, at least a comparison can be made even if the specimens of the same size are used even if they are appropriately small. . As a tensile tester, for example, AOUTGRAPHAGS-G100N manufactured by SHIMADZU can be used.
-"Developed state" means a state where the plate is flattened without contraction or slack.
-Unless otherwise specified, the dimensions of each part mean dimensions in a deployed state, not a natural length state.
・ If there is no description about the environmental conditions in the test and measurement, the test and measurement shall be performed in a test room or equipment in the standard condition (test location is temperature 20 ± 5 ℃, relative humidity 65% or less). .

  The elastic film stretchable structure of the present invention can be applied to an exterior body of a pants-type disposable diaper.

  B ... Rear body, F ... Front body, T ... Body circumference part, L ... Middle part, 10 ... Interior body, 10B ... Inside / outside fixing region, 11 ... Liquid-permeable top sheet, 12 ... Liquid-impermeable sheet, 13 ... Absorber, 13N ... Constricted portion, 14 ... Packaging sheet, 95 ... Gathered nonwoven fabric, 96 ... Gather elastic member, 17 ... Non-absorbent side, 20 ... Exterior body, 20A ... First sheet layer, 20B ... Second sheet layer, 20C ... folded portion, 20X ... elastic film stretchable structure, 21 ... side seal part, 23 ... waist end region, 24 ... waist elastic member, 25 ... contraction collar, 29 ... leg circumference line, 30 ... elastic film, 31 ... Through hole, 40 ... sheet joint, 70 ... non-stretchable region, 80 ... stretchable region, 84 ... weakly stretchable region, 90 ... solid gathering.

Claims (5)

An exterior body that individually or integrally configures the front body and the back body, and an interior body including an absorber attached to the exterior body so as to reach the back body from the front body through the crotch part,
A waist opening and a pair of left and right leg openings are formed by joining the side edge portions of the exterior body in the front body and the side edge portions of the exterior body in the back body to form a side seal portion. ,
In pants-type disposable diapers,
In the crotch portion of the absorbent body, a narrowed portion narrower than both front and rear sides is formed, and both side portions of the interior body corresponding to the narrowed portion of the absorbent body have no absorbent body. And
The exterior body extends laterally from a side edge of the absorber,
The interior body is fixed to the exterior body in a width extending from one non-absorbent body side to the other non-absorbent body side, and in the inner and outer fixing regions extending from the front and rear sides of the non-absorbent body side,
A three-dimensional gather that stands on the skin side of the wearer from both side edges of the interior body is provided over both front and rear sides of the non-absorbent body side,
The exterior body has a first sheet layer extending from the front-rear direction range corresponding to the narrowest portion of the constricted portion to the front-rear direction range corresponding to the side seal portion in at least one of the front body and the rear body. In addition, an elastic film is laminated between the second sheet layer, and the first sheet layer and the second sheet layer are directly or indirectly joined at a plurality of sheet joint portions arranged at intervals. , Has an elastic film stretchable structure,
The region having the elastic film stretchable structure in the exterior body has a stretchable region that is shrinkable in the width direction due to the shrinkage of the elastic film, and is stretchable in the width direction,
This stretchable region includes a portion for fixing at least the non-absorbent side of the inner and outer fixed region to the exterior body,
The exterior body does not have an elongated elastic elastic member extending along the leg opening,
A pants-type disposable diaper characterized by that.   The outer body of the front body has the elastic film stretchable structure from the front-rear direction range corresponding to the narrowest part of the constricted part to the front-rear direction range corresponding to the side seal part, and its elasticity The pants-type disposable diaper according to claim 1, wherein a region overlapping with the inner and outer fixed regions among the regions having a film stretchable structure is a weak stretchable region having a shorter elastic limit elongation than a region located on the side thereof.   The outer body of the rear body has the elastic film stretchable structure over the front-rear direction range corresponding to the side seal portion and the front-rear direction range, and the inner and outer sides of the region having the elastic film stretchable structure. The pants-type disposable diaper according to claim 2, wherein a region overlapping with the fixed region is a non-stretchable region. Each of the front body and the back body has an elastic film stretchable structure, and the elastic film constituting the elastic film stretchable structure of the front body and the elastic film constituting the elastic film stretchable structure of the back body are separated front and back And separated in the front-rear direction,
The underpants type disposable of Claim 2 or 3 by which the rear end of the elastic film which comprises the elastic film elastic structure of the said front body is located in the range from the front-back direction center of a pants type disposable diaper to 60 mm to the front side. Diapers.   The stretchable region in the elastic film stretchable structure provided from the front-rear direction range corresponding to the narrowest portion of the constricted portion to the front-rear direction range corresponding to the side seal portion is from the side seal portion to the The edge area | region of the leg opening to the side edge of the area | region which overlaps with a non-absorbent body side part has the weak extension stress of the width direction rather than the part adjacent to the waist side, The any one of Claims 1-4. Pants-type disposable diaper.