JP6681866B2 - Elastic member and pants-type disposable wearing article having the elastic member - Google Patents

Description

  The present invention relates to an elastic member having an elastic structure in which an elastic sheet such as an elastic sheet is sandwiched between a first sheet layer and a second sheet layer, and a pants-type disposable wearing article having the elastic member.

  BACKGROUND ART In a disposable wearing article such as a disposable diaper, it is common to give elasticity to appropriate places such as around the legs and around the waist in order to improve the fit to the body surface. As a method for giving elasticity, conventionally, a method of attaching an elongated elastic member such as a rubber thread in a state of being elongated in its longitudinal direction has been widely adopted, but when giving elasticity to a certain width , A mode in which thread rubbers are fixed in a state where they are arranged side by side at intervals in the width is adopted. In addition, a method of attaching the elastic sheet in a stretched state in the direction of imparting elasticity has been proposed, including the one of the present applicant, as one having even better fit as a surface. (See, for example, Patent Documents 1 and 2).

The elastic structure using the elastic film (hereinafter, also referred to as elastic sheet elastic structure) is formed by laminating an elastic film between a first sheet layer whose elastic region is made of a nonwoven fabric and a second sheet layer made of a nonwoven fabric. , The elastic film is stretched in the direction of expansion and contraction along those surfaces, and the first sheet layer and the second sheet layer are arranged in the direction of expansion and contraction and in a direction orthogonal thereto in a large number of dots. The sheet bonding portion is bonded through a bonding hole penetrating the elastic film.
In such an elastic sheet stretchable structure, in the natural length state, the elastic film shrinks between the sheet joints, so that the distance between the sheet joints becomes narrower, and the sheet joints in the first sheet layer and the second sheet layer become closer to each other. Shrink wrinkles are formed that extend in a direction intersecting with the expansion / contraction direction.
On the other hand, at the time of stretching, as the elastic film stretches between the sheet joints, the space between the sheet joints and the shrinkage creases 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 expanded state. This elastic sheet expansion / contraction structure is excellent not only in surface fit, but also in the first sheet layer and the second sheet layer and the elastic film is not joined at the surface, and the first sheet layer and the second sheet layer are joined together. Since the number of bonding points is extremely small, it is very flexible, and the bonding holes of the elastic film also have the advantage of contributing to the improvement of air permeability in the thickness direction.

  However, when the shrink wrinkles are long and continuous, the appearance is observed as uniform wrinkles of shrink wrinkles in one direction and becomes monotonous, and the appeal of the product to consumers is poor.

Japanese Patent No. 5967736 JP-A-2015-204982

  Therefore, a main object of the present invention is to provide a shrink wrinkle that is not monotonic and has a complicated appearance, and is excellent in appealing to consumers when it is applied to an absorbent article.

The elastic member of the present invention which has solved the above problems,
An elastic sheet is interposed between a breathable first sheet layer and a breathable second sheet layer, and the first sheet layer and the second sheet layer are formed with a large number of sheet joining portions at intervals. In addition, the elastic sheet stretchable structure is joined through a joining hole penetrating the elastic sheet or through the elastic sheet,
The elastic region showing the elastic sheet elastic structure can be expanded and contracted in the elastic direction by the elastic force of the elastic sheet,
The joint portion has a joint portion row formed at intervals along a direction orthogonal to the expansion and contraction direction,
A large number of the joining portion rows are formed at intervals in the expansion and contraction direction,
A third joint portion row is formed between the first joint portion row and the second joint portion row which are adjacent to each other,
At least part of the distance in the direction the perpendicular of said third junction sequence is longer than the distance in the direction the perpendicular in the third first junction sequence and the second joined section columns on both sides of the junction sequence ,
It is characterized by that.

When the third at least a portion of the interval in the direction the orthogonal junction sequence is longer than the distance in the direction orthogonal to the first joint part row and the second joining portion rows on both sides of the third joint part row, first It is possible to form a shrink wrinkle between the joining portion row and the second joining portion row, in which the length of the joining portion of the third joining portion row and the joining portion is limited.
If the third joint portion does not exist, the shrink creases generated in the entire space between the first joint portion row and the second joint portion row have long pleats (hereinafter, "inter-row continuous pleat"). Also, the continuous pleats between rows are wavy in the expansion and contraction direction, and are monotonous in appearance.
On the other hand, the contraction wrinkle generated according to the present invention is a contraction wrinkle in which the length of the joint portion of the third joint portion row and the joint portion is limited, and is not continuous in the entire orthogonal direction. Since the contraction wrinkles are dispersed and appear in the direction of expansion and contraction and the direction orthogonal to each other, the appearance is excellent.
In other words, the shrinking wrinkles are not monotonic and have a complicated appearance, and when they are applied to an absorbent article, they have excellent appeal to consumers.

An angle intersecting the orthogonal direction and the expansion / contraction direction may be 45 degrees to 135 degrees.
By providing the intersecting angle, when applied to an absorbent article, the shrinkable wrinkles can be made to appear in an oblique direction rather than being aligned in the front-rear direction, and for example, a rubber thread group can be made to appear in the absorbent article. By arranging the wrinkles in the width direction, a peculiar appearance, which is different from the form in which contraction wrinkles are exposed in the front-rear direction, can be exhibited, and the appeal to consumers is excellent.

  The joint portion of the third joint portion row, together with the joint portion of the first joint portion row and the joint portion of the second joint portion row which are adjacent to each other, forms an intersecting row that is aligned in the direction crossing the joint portion row group. Forms can be provided.

Shrinkage wrinkles are formed on both sides of the joint row in a direction orthogonal to each other. On the contrary, between the shrinking wrinkles in the orthogonal direction and the shrinking wrinkles in the orthogonal direction is the joint line. If the joint row between the shrink creases is continuous in the entire orthogonal direction , the ventilation path is generally straight.
However, when the wearer wears the absorbent article, the way the wearer's skin hits the stretchable area (for example, whether it hits strongly or weakly) may differ, and in this case, the ventilation path is partially insufficient. Sometimes.
On the other hand, when the third joint portion row is formed, a ventilation passage is formed along the third joint portion row, and the ventilation passage in the orthogonal direction and the ventilation passage in the direction crossing the joint portion row group communicate with each other, As a result of forming the mesh-shaped ventilation path, stuffiness emitted from the wearer can be exhausted through the mesh-shaped ventilation path.

The intersecting rows may be formed as a plurality of rows at intervals in the orthogonal direction .
The appearance of the contraction wrinkles in the orthogonal direction and the discontinuity between the contraction wrinkles becomes clear in appearance, and the design becomes clear.
There is also an advantage that the ventilation path can be sufficiently secured.

An integrated exterior body extending from the front body to the back body, or an exterior body separately provided on the front body and the back body, and an interior body attached to the widthwise middle portion of the exterior body extending over the front and rear sides of the crotch area. The side seal part in which both sides of the exterior body in the front body and both sides of the exterior body in the back body are respectively joined, a waist opening, and a pair of left and right leg openings are provided. A pants-type disposable wearing article having the elastic member according to item 1,
The outer body of at least one of the front body and the back body extends at least in a part of the front-rear direction across the width direction range corresponding to the side seal portions, and the elastic member expands and contracts in the width direction. Is provided,
A pants-type disposable wearing article having an elastic member.
It is characterized by that.

  When the stretchable member is applied as an exterior body in a pants-type disposable wearing article, it is a product that sufficiently exhibits the advantages relating to the appearance obtained according to the present invention.

  As described above, according to the present invention, shrinkage wrinkles have a complex appearance rather than a monotonous appearance, and when this is applied to an absorbent article, it has excellent appeal to consumers.

It is a top view (inner surface side) of the pants type disposable diaper in a developed state. It is a top view (outer surface side) of the pants type disposable diaper in a developed state. It is a top view which shows only the principal part of the pants type disposable diaper in an expanded state. (A) is CC sectional drawing of FIG. 1, (b) is EE sectional drawing of FIG. It is an AA sectional view of FIG. It is a BB sectional view of FIG. It is a principal part top view (inner surface side) of the expansion-contraction area | region in the pants type disposable diaper in a deployment state. (A) is sectional drawing corresponding to CC line of FIG. 1, (b) is sectional drawing corresponding to EE line of FIG. FIG. 6 is a plan view and a cross-sectional view showing a joint portion array disclosed in Patent Document 1. It is a top view which shows the joining part arrangement which the patent document 2 discloses. It is a top view which shows the joining part arrangement | positioning as an explanatory reference example. 1 illustrates a first embodiment of a joint array according to the present invention. It is a top view which shows the 2nd Example of the joining part arrangement | sequence of this invention. It is a top view which shows the 3rd Example of the joining part arrangement | sequence of this invention. It is a top view which shows the 4th Example of the joining part arrangement | sequence of this invention. It is a top view which shows the 5th Example of the joining part arrangement | sequence of this invention. It is a top view which shows the 6th Example of the joining part arrangement | sequence of this invention. It is a top view which shows the 7th Example of the joining part arrangement | sequence of this invention. It is a top view which shows the 8th Example of the joining part arrangement | sequence of this invention. It is a top view which shows the 9th Example of the joining part arrangement | sequence of this invention. It is a top view which shows the 10th Example of the joining part arrangement | sequence of this invention. It is a top view which shows the 11th Example of the joining part arrangement | sequence of this invention. It is a top view which shows the 12th Example of the joining part arrangement | sequence of this invention. It is a top view which shows the 13th Example of the joining part arrangement | sequence of this invention. It is a top view which shows the 14th Example of the joining part arrangement | sequence of this invention. It is a top view which shows the example of a joining form in a joining part. It is an explanatory sectional view showing an example of joining form. It is an explanatory sectional view showing an example of joining form. It is a top view showing an example of joining form. It is a schematic diagram of an ultrasonic sealing device for manufacturing an elastic member.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings. In addition, a dotted pattern portion in the cross-sectional view indicates a joining means such as a hot melt adhesive.
1 to 6 show a pants-type disposable diaper as an example of the disposable wearing article of the present invention. Reference numeral LD (longitudinal direction) indicates the front-rear direction, and WD indicates the width direction.
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. Therefore, the inner body 10 is configured such that the absorber 13 is interposed between the liquid-permeable top sheet 11 and the liquid-impermeable sheet 12. In manufacturing, the inner body 10 and the outer body 20 are joined to the inner surface (upper surface) of the outer body 20 by a joining means such as a hot-melt adhesive, and then the inner body 10 and the outer body 20 are joined to the front body F and the back body B. It is folded at the center of the front-back direction LD (longitudinal direction), which is the boundary of the, and both side portions are joined to each other by heat welding or hot-melt adhesive to form the side seal portion 21. A disposable pants-type diaper having a pair of leg openings formed therein.

(Example of structure of interior)
As shown in FIGS. 4 to 6, the inner 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. And absorbs and retains the excreted liquid that has permeated the top sheet 11. The planar shape of the inner body 10 is not particularly limited, but it is generally a substantially rectangular shape as shown in FIG.

  As the liquid-permeable top sheet 11 that covers the front side (skin side) of the absorber 13, a perforated or non-perforated nonwoven fabric, a porous plastic sheet, or the like is preferably used. The material fibers that make up the non-woven fabric can be synthetic fibers such as olefins such as polyethylene or polypropylene, polyesters, polyamides, etc., regenerated fibers such as rayon or cupra, and natural fibers such as cotton. 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 flexibility and drapability, and the thermal bond method is excellent in bulkiness and softness. 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 topsheet 11 extends up to the back side of the absorbent body 13 with the side edge portion of the absorbent body 13 wrapped around.

  The liquid-impermeable sheet 12 covering the back side (non-skin contact side) of the absorbent body 13 is a liquid-impermeable plastic sheet such as polyethylene or polypropylene, but in recent years, it has moisture permeability from the viewpoint of preventing stuffiness. Is preferably used. This water-impermeable / 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 the sheet uniaxially or biaxially. is there.

  The absorbent body 13 is a well-known one, for example, a piled body of pulp fibers, an aggregate of filaments such as cellulose acetate, or a non-woven fabric, which is prepared by mixing and fixing a superabsorbent polymer as necessary. Can be used. The absorbent body 13 can be packaged with a packaging sheet 14 having liquid permeability and liquid retaining property, such as crepe paper, if necessary, for shape and polymer retention.

  The shape of the absorber 13 is formed in a substantially hourglass shape having a narrowed portion 13N in the crotch portion which is narrower than the front and rear sides. The size of the constricted portion 13N can be appropriately determined, but the length of the constricted portion 13N in the front-rear direction can be set to about 20 to 50% of the total length of the diaper, and the width of the narrowest portion thereof is 40% of the total width of the absorbent body 13. It can be about 60%. In the case where the inner body 10 has such a constricted portion 13N and the planar shape of the inner body 10 is substantially rectangular, the inner body 10 does not have the absorber 13 at a portion corresponding to the constricted portion 13N of the absorber 13. The absorber side portion 17 is formed.

  The liquid-impermeable sheet 12 is folded back together with the liquid-permeable top sheet 11 on both sides in the width direction of the absorber 13. As the liquid impermeable sheet 12, it is desirable to use an opaque sheet so as not to give a brown color such as defecation or urine. As the opacifying agent, a film obtained by internally adding a pigment or a filler such as calcium carbonate, titanium oxide, zinc oxide, white carbon, clay, talc, or barium sulfate to a plastic is preferably used.

  Three-dimensional gathers 90 that fit around the legs are formed on both sides of the inner body 10. As shown in FIGS. 5 and 6, the three-dimensional gather 90 includes a fixing portion 91 fixed to a side portion of the back surface of the inner body 10 and a side portion of the inner body 10 from the fixing portion 91. A body portion 92 extending to a side portion of the surface of the body and a fall formed by fixing the front and rear ends of the body portion 92 to the side portion of the surface (the top sheet 11 in the illustrated embodiment) of the inner body 10 in a fall state. It has a portion 93 and a free portion 94 formed by non-fixing between the fallen portions 93. Each of these portions is formed by a gather sheet 95 that is a double sheet obtained by folding back a sheet of non-woven fabric or the like. The gather sheet 95 is attached over the entire front-rear direction of the interior body 10, the collapse portions 93 are provided on the front side and the rear side of the non-absorbent body side portion 17, and the free portions 94 are provided on both front and rear sides of the non-absorbent body side portion 17. It has been extended. Further, between the double gather sheets 95, an elongated gather elastic member 96 is arranged at the tip of the free portion or the like. The gather elastic member 96 is for raising the free portion 94 by elastic expansion / contraction force as shown in FIG. 5 in a product state.

  In the embodiment shown in FIGS. 5 and 6, the gather elastic member 96 is adhesively fixed to the gather sheet 95 via the hot melt adhesive at the position of the gather elastic member 96 except the fallen non-stretchable portion 97, and the gather sheet 95 is used. However, the gather elastic member 96 does not have the hot melt adhesive at the position of the gather elastic member 96, and therefore the gather elastic member 96 and the gather sheet 95 are not adhered to each other. The facing surface of the gather sheet 95 is not joined at the position where the member 96 is provided.

  The three-dimensional gather 90 shown in FIGS. 5 and 6 has a shape in which the main body 92 is not folded back.

  As the gather elastic member 96, a commonly used material such as styrene rubber, olefin rubber, urethane rubber, ester rubber, polyurethane, polyethylene, polystyrene, styrene butadiene, silicone or polyester can be used. Further, 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-shaped member having a certain width can be used in addition to the thread-shaped member shown in the drawing.

  Similar to the liquid-permeable top sheet 11, the material fibers forming the gather sheet 95 are synthetic fibers such as olefins such as polyethylene or polypropylene, polyesters, polyamides, etc., recycled fibers such as rayon and cupra, and cotton. It is possible to use natural fibers such as, spun bond method, thermal bond method, melt blown method, can be used nonwoven fabric obtained by an appropriate processing method such as a needle punch method, but especially to prevent stuffiness It is preferable to use a non-woven fabric having a low basis weight and excellent breathability. Further, regarding the gather sheet 95, in order to prevent permeation of urine and the like, and to prevent rash and enhance the feel (dry feeling) to the skin, a silicone-based, paraffin metal-based, alkyl chromic chloride-based water repellent, etc. It is desirable to use a water repellent non-woven fabric coated with.

  As shown in FIGS. 3 to 6, the back surface of the inner body 10 is joined to the inner surface of the outer body 20 in the inner / outer fixing region 10B (hatched region) with a hot melt adhesive or the like. The inner / outer fixed region 10B can be appropriately determined and can be substantially the entire width direction WD of the inner body 10, but it is preferable that both ends in the width direction are not fixed to the outer body 20.

(External body structure example)
The exterior body 20 extends outward from the side edge of the absorber 13. In the crotch portion of the exterior body 20, the side edge of the exterior body 20 may be located closer to the center in the width direction than the side edge of the interior body 10 in the crotch portion, or may be located outside in the width direction. Further, the exterior body 20 is a front-rear direction range between the waist circumference T corresponding to the side seal portion 21 and the waist circumference T of the front body F and the waist circumference T of the back body B. And an intermediate portion L.

Then, in the exterior body 20 of the illustrated form, as shown in FIGS. 2 and 4 to 6, except for the front-rear direction intermediate portion of the intermediate portion L, between the first sheet layer 20A and the second sheet layer 20B. , An elastic sheet such as an elastic film 30 is interposed, and as shown in FIG. 9, the first sheet layer 20A and the second sheet layer 20B are elastic at a number of sheet joint portions 40 arranged at intervals. The elastic sheet stretchable structure 20X is joined through a joining hole 31 penetrating the film 30.
In the application form to the diaper, the elastic sheet (the elastic film 30 in the example of FIG. 9) stretching direction ED is the width direction WD of the diaper.

  The first sheet layer 20A and the second sheet layer 20B may be indirectly bonded via the elastic film 30 instead of through the bonding hole 31 of the elastic film 30. The planar shape of the exterior body 20 is formed by the concave leg-surrounding lines 29 so that both side edges in the width direction of the intermediate portion L respectively form leg openings, and has an hourglass-like shape as a whole. The exterior body 20 may be formed separately in the front body F and the back body B, and both may be arranged so as to be separated from each other in the front-rear direction LD of the diaper at the crotch portion.

  1 and 2 is a form in which the elastic sheet elastic structure 20X extends to the waist end 23, but when the elastic sheet elastic structure 20X is used for the waist end 23, If necessary, such as insufficient tightening, the waist end 23 is not provided with the elastic sheet elastic structure 20X as shown in FIG. 7 and FIG. 8 and is expanded and contracted by the conventional elongate waist elastic member 24. A structure can also be provided. The waist elastic member 24 is an elongated elastic member such as a plurality of rubber threads arranged at intervals in the front-rear direction LD, and gives an elastic force so as to tighten around the waist of the body. The waist elastic members 24 are not arranged closely as a bundle and are substantially arranged as one bundle, and three or more waist elastic members 24 are provided at intervals of about 3 to 8 mm in the front-rear direction so as to form a predetermined expansion / contraction zone. , Preferably 5 or more. The extension rate of the waist elastic member 24 when fixed can be appropriately determined, but in the case of a normal adult, it can be set to about 230 to 320%. The waist elastic member 24 uses thread rubber in the illustrated example, but other elongated elastic members such as flat rubber may be used. Although not shown, the elastic film 30 may be provided at the waist end 23, and the elongated waist elastic member 24 may be provided at a position overlapping with the elastic film 30 to provide an elastic structure with both elastic members. In the illustrated embodiment, the elongated elastic member extending along the leg opening is not provided at the edge portion of the leg opening in the exterior body 20, but at a position overlapping the elastic film 30 at the edge portion or at the edge. An elongated elastic member may be provided in place of the elastic film 30 of the portion.

  As another form, although not shown, the elastic sheet elastic structure 20X is not provided in the intermediate portion L between the waist portion T of the front body F and the waist portion T of the back body B, or the front body An elastic sheet elastic structure 20X is continuously provided in the front-rear direction LD from inside the waist region T of F to the inside of the waist region T of the back body B, or either the front body F or the back body B. Appropriate modifications such as providing the elastic sheet expansion and contraction structure 20X only in the above are also possible.

(Form of joint)
The present invention is characterized by the arrangement of the joints. In order to clarify this feature, the arrangement of the joint portion in the conventional example will be specifically described.

FIG. 9 is shown as a representative example in Patent Document 1.
That is, the joint portions 40 are arranged in a staggered arrangement, and the joint portions 40 are elongated in a direction orthogonal to the expansion / contraction direction and are line-symmetrical (horizontal symmetry in FIG. 9A) with respect to a center line passing through the center of the expansion / contraction direction. The width 40x of the joint portion 40 in the expansion / contraction direction is preferably 0.2 to 0.4 mm, and the distance d1 between the joint portions 40 arranged in the expansion / contraction direction is 3 to 12.9 mm, more preferably 5 to 5. The distance d2 is 6.4 mm, and the distance d2 between the joint portions 40 arranged in the direction orthogonal to the expansion / contraction direction is 2 to 10.5 mm, and more preferably 2.3 to 4.6 mm.
In this way, the joint portions 40 having a remarkably narrow width 40x in the expansion / contraction direction are arranged in a zigzag pattern at a somewhat wide spacing d1 in the expansion / contraction direction, and the contraction force of the elastic film 30 is directly applied to each joint portion 40. Functioning to maintain the arrangement and spacing of the joint portions 40 at the positions of the joint holes 31 of the elastic film 30, the flexibility is less likely to decrease. Further, the folds 25f extend almost straight along the direction orthogonal to the expansion and contraction direction, and the joint 40 is hidden between the folds 25f and the folds 25f to make them inconspicuous. Therefore, the elastic sheet stretchable structure 20X has an appearance closer to that of cloth, while suppressing deterioration in flexibility.

  On the other hand, although the arrangement of the joints 40 is a staggered arrangement, if the shape of the joints 40 is circular, the joints 40 are not only clearly visible between the wrinkles 25f and the folds 25f. Since the folds 25f greatly extend around the joint portion 40 and extend in the direction orthogonal to the expansion / contraction direction, the wavy folds 25f are formed as a whole, and the appearance like a cloth tends not to be obtained.

  From this point of view, the shape of the joint 40 is preferably elongated in the direction orthogonal to the expansion / contraction direction. However, if the maximum length of the joint portion 40 in the direction orthogonal to the expansion / contraction direction is too short or too long, the linearity of the folds 25f may be reduced or the flexibility thereof may be reduced. Therefore, although these dimensions can be appropriately determined, it is preferable that the length 40y in the direction orthogonal to the expansion / contraction direction of the joint 40 is 0.4 to 3.2 mm, and particularly 0.7 to 1.4 mm. Has been done.

On the other hand, in Patent Document 2, in both of the two examples shown in FIGS. 10 (a) and 10 (b), the openings of the stretchable film (illustrated by a vertically long rectangle) are also arranged in a staggered arrangement. In the example of 1), the small circular sub-joint is arranged between the rectangular main openings. The example (b) is also based on the idea of the staggered arrangement.
The arrangement and dimensions of the openings are preferably in the dimension range (unit is mm) shown in FIG. 10, mainly in terms of appearance, touch and breathability.

Both inventions of Patent Documents 1 and 2 disclose a vertically elongated opening portion and also a staggered arrangement.
However, in the conventional example, since the separation distance between the openings of the elastic film in the direction orthogonal to the stretching direction is set to be large, the stretching stress in the stretching direction is high, and is excessive when applied to a pants-type disposable diaper, for example. There are not a few wearers who feel that they will be strongly tightened (in the width direction).
Here, the opening length B is 0.3 to 0.7 mm, and the spacing H is 0.6 to 1.4 mm.

On the other hand, as shown in FIG. 11, the present inventor expands and contracts by setting a small spacing between the openings of the elastic film in the direction orthogonal to the expanding and contracting direction (vertical direction in the drawing: the direction of the symbol LD). It was found that the stretching stress in the direction can be reduced, and when applied to a pants-type disposable diaper, it can be gently fitted to the wearer with a weak tightening force.
The reason is that the opening is opened in the width direction to form the bonding hole 31 as shown in FIG. 9 only by applying a small extension force from the outside in the width direction (extending and contracting direction of the elastic film). In the spaced area orthogonal to the direction of expansion and contraction between the parts, even if it is stretched in the width direction, there is no opening, so the stretching stress of the elastic film becomes the shrinking force as it is to tighten the wearer. It is believed that there is.

The form shown in FIG. 11 can be fitted to the wearer gently, and is excellent in breathability because the area ratio occupied by the joint portion and the area ratio occupied by the joint hole in the extended use state in the width direction are high. It also brings advantages.
However, in the usage pattern of the product shown in FIG.
A junction 40, 40 ... row of along the orthogonal direction LD, which the spaced area between the joint portion 40, 40 ... row of adjacent spaced stretch direction ED (width direction), perpendicular to the direction (perpendicular direction ) Wrinkles are formed along the LD. As shown in FIG. 11 (b), the wrinkles 25F simply have a uniform mountain shape. That is, the cross section shown in Patent Document 1 is different from that shown in FIG. 9C.
When the configuration shown in FIG. 11 is viewed from the design point of view as the entire stretchable region of the product, long creases 25F (continuous pleats between rows) are formed in the stretchable direction ED (width direction) uniformly and repeatedly in the orthogonal direction LD. It has a simple design, and the product lacks appeal.

The present invention has the first joint portion and the second joint portion, and specifically has the configuration described in the claims, and includes various forms and also includes combinations of various forms.
Due to the paper width, representative examples will be sequentially described below.
12 to 25 illustrate the arrangement of the joint portion 40 between the first sheet layer 20A and the second sheet layer 20B, and the contraction wrinkles 26 are generated by contraction of the elastic sheet, for example, the elastic film 30. Indicated. The shape of the joining portion 40 can be appropriately selected, but the example is a rectangular shape.
In addition, the ventilation path is indicated by reference sign PW (path of broken line).

<First embodiment>
In the stretchable member according to the first embodiment shown in FIG. 12, an elastic sheet (not shown) is provided between a breathable first sheet layer (not shown) and a breathable second sheet layer (not shown). (Not shown), the first sheet layer and the second sheet layer are provided at a plurality of sheet joining portions 40 arranged at intervals, through joining holes (not shown) penetrating the elastic sheet. Alternatively, it is provided with an elastic sheet stretchable structure joined through the elastic sheet.
Further, the stretchable region showing the stretchable structure of the elastic sheet can be stretched in the stretching direction by the stretching force of the elastic sheet.

In the present invention, the joint portions 40 are formed with joint portions rows that are spaced from each other along the orthogonal direction that intersects with the expansion / contraction direction (orthogonally intersects in the illustrated example of FIG. 12). In the illustrated example of 12, they are aligned vertically.)

In FIG. 12, a third joint portion row A3 is formed between the first joint portion row A1 and the second joint portion row A2 which are adjacent to each other, and at least a part of the third joint portion row A3 in a direction orthogonal to each other. S3 is longer than the intervals S1 and S2 in the orthogonal directions in the first joint portion row A1 and the second joint portion row A2 on both sides of the third joint portion row A3.

In this mode, the contraction wrinkle 26 having a limited length across the joint portion 40 and the joint portion 40 of the third joint portion row A3 is provided between the first joint portion row A1 and the second joint portion row A2. Can be formed.
If the third joint portion 40 does not exist, the contraction wrinkles generated between the first joint portion row A1 and the second joint portion row A2 may be long pleats as shown in FIG. In other words, it becomes a continuous pleat between rows, and the continuous pleat between rows has a wavy shape in the expansion and contraction direction, and is monotonous in appearance.
On the other hand, the contraction wrinkle 26 produced according to the present invention extends between the joint portion 40 and the joint portion 40 of the third joint portion row A3 between the first joint portion row A1 and the second joint portion row A2. Since the contraction wrinkles 26 are limited in length and are not continuous in the entire orthogonal direction , the contraction wrinkles 26 appear in a distributed manner in the expansion / contraction direction and the orthogonal direction , so that the appearance is excellent.
In other words, the shrinkable wrinkles 26 have a complex appearance rather than a monotonous appearance, and when this is applied to an absorbent article, it has excellent appeal to consumers.

Note that the orthogonal direction is not orthogonal to the expansion / contraction direction ED (WD) as in the example of FIG. 25 described later, but the intersecting angle θ can be intersected within a range of 45 degrees to 135 degrees, for example. .
By having the intersecting angle, when applied to an absorbent article, the contracted wrinkles 26 can be exposed in an oblique direction instead of being aligned with the contracted wrinkles in the front-rear direction. By arranging them in the width direction of the article, it is possible to bring out a peculiar appearance, which is different from the conventional form in which contraction wrinkles appear in the front-rear direction, and is excellent in appealing power to consumers.

  On the other hand, as shown in FIG. 12, the joint portion 40 of the third joint portion row is joined with the joint portion 40 of the first joint portion A1 row and the joint portion 40 of the second joint portion row which are adjacent to each other. Embodiments can be provided in which intersecting rows X are formed that are aligned across the group.

Shrink wrinkles 26 are formed on both sides of the joint line in a direction orthogonal to each other. On the contrary, a joint line exists between the shrinking wrinkles 26 in the orthogonal direction and the shrinking wrinkles 26 in the orthogonal direction . If the joint row between the shrink creases 26, 26 is continuous in the entire orthogonal direction , the ventilation path is generally linear.
However, when the wearer wears the absorbent article, the way the wearer's skin hits the stretchable area (for example, whether it hits strongly or weakly) may differ, and in this case, the ventilation path is partially insufficient. Sometimes.
On the other hand, when the third joining portion row A3 is formed, the ventilation path PW is formed along the joining portion 40 of the third joining portion row A3, and the ventilation path PW in the orthogonal direction and the direction crossing the joining portion row group are formed. As a result of the mesh-like ventilation path PW being formed by communicating with the ventilation path PW of the above, the stuffiness emitted from the wearer can be exhausted through the mesh-like ventilation path PW.

<Second embodiment>
The embodiment shown in FIG. 13 is an example in which the joints 40 of the first joint A1 row and the joints 40 of the second joint row have different shapes and dimensions, and the intervals S1 and S2 are different.

<Third embodiment>
In the embodiment shown in FIG. 14, the joint portion 40 of the third joint portion row traverses the joint portion row group together with the adjoining joint portion 40 of the first joint portion A1 row and the joint portion 40 of the second joint portion row. This is a form in which intersecting rows X aligned in the direction are formed. In particular, two intersecting rows X are formed. The width of the ventilation path PW (the vertical width in the illustrated example) is larger than that in the first embodiment, and the air permeability is high.

<Fourth Embodiment>
The embodiment shown in FIG. 15 is an example in which the contraction wrinkles 26 are formed in different steps. The design is not monotonous but complex, giving a sense of luxury. Further, the ventilation path PW is formed in a step shape.

<Fifth Embodiment>
The embodiment shown in FIG. 16 is an example in which the contraction wrinkles 26 are formed in a wavy shape as a whole. The design is not monotonous but gives a sense of dynamism. Further, the ventilation path PW is formed in a wave shape.

<Sixth embodiment>
The embodiment shown in FIG. 17 is an example in which the contraction wrinkles 26 are formed as hexagons with substantially rounded corners. The design is not monotonous, but it can be interesting. Further, the ventilation path PW is formed in a honeycomb.

<Seventh embodiment>
The embodiment shown in FIG. 18 is an example in which the contraction wrinkle 26 is formed as a more complicated upper and lower elongated shape. The design is not monotonous, but it can be interesting. Further, the ventilation path PW is formed in a square wave shape.

<Eighth Example>
The embodiment shown in FIG. 19 is an example in which the intersecting rows are inclined. The contraction wrinkle 26 is one in which an inclined rectangle is generated. The design is not monotonous, but it can be interesting.

<Ninth Example>
The embodiment shown in FIG. 20 is different from the example of FIG. 18 in that the presence of the joint portions 40, 40 of the first joint portion row A1 causes the annular contraction wrinkle 26 to be generated. . The design is not monotonous, but it can be interesting. Further, the ventilation path PW is formed in a square wave shape.

<Tenth Example>
The embodiment shown in FIG. 21 is an example in which the intersecting rows are inclined in the opposite direction to the example in FIG. The contraction wrinkle 26 is one in which an inclined rectangle is generated. The design is not monotonous, but it can be interesting.

<Eleventh embodiment>
The embodiment shown in FIG. 22 is an example in which the intersecting rows are inclined in a plurality of rows, three rows in the illustrated example. The contraction wrinkle 26 is one in which an inclined rectangle is generated. The design is not monotonous, but it can be interesting.

<Twelfth Example>
In the embodiment shown in FIG. 23, shrink wrinkles 26 having different sizes are generated. The design is not monotonous, but it can be interesting.

<13th Example>
In the embodiment shown in FIG. 24, three types of contraction wrinkles 26 having different sizes are generated. The design is not monotonous, but it can be interesting.

<Fourteenth embodiment>
In the above example, the orthogonal direction is orthogonal to the expansion / contraction direction ED (WD), but instead of being orthogonal to the contraction direction ED (WD) as in the example of FIG. 25, the intersecting angle θ is 45, for example. It is possible to intersect within a range of degrees to 135 degrees. The design is not monotonous, but it can be interesting. The intersecting angle θ is preferably 50 degrees to 130 degrees, and particularly preferably 60 degrees to 120 degrees.

  In relation to the fourteenth embodiment shown in FIG. 25, the advantage of tilting the joint row instead of making it orthogonal to the contraction direction ED (WD) (that is, not θ = 90 degrees) is from a design point of view. There are other advantages as well. Then, the advantage is demonstrated.

That is, as can be seen from FIG. 25, the separation distance between the joint portions 40, 40 can be increased on the orthogonal direction line. In the example of FIG. 12, in the first joint portion row A1 and the second joint portion row A2, the spacing between the joint portions 40, 40 is extremely narrow. As described above, it is desirable that the first sheet layer 20A and the second sheet layer 20B be joined at the sheet joining portion 40 by joining means such as heat sealing or ultrasonic sealing by material welding.
In the case of continuous production, seal melting by ultrasonic waves is performed between the anvil roll and the ultrasonic horn, but in order to prevent energy loss, the ultrasonic horn should also be in close contact with the sheet in the entire axial direction of the anvil roll. It is important to provide a large ultrasonic output when forming a pattern having a large proportion of convex portions of the anvil roll, such as the joints 40, 40 ... Rows along the generatrix that makes line contact. Therefore, it is necessary to apply an excessive close force along the generatrix that makes line contact, and this imposes a heavy burden on the facility side.
On the other hand, in the case of the fourteenth embodiment shown in FIG. 25 (generally in the case of the inclined arrangement), the proportion of the joint portion located on the line in the orthogonal direction is small, and the stable linear pressure is obtained. Facility load is small and stable operation is possible.

The joint 40 has a length of 0.3 to 7.0 mm as a reference in the orthogonal direction, preferably 0.5 to 5.0 mm, and particularly preferably 0.7 to 2.5 mm. The width of the joint 40 is preferably 0.2 to 1.0 mm.
Further, the joint portions 40, 40 ... Rows are formed with a formation pitch of 2.0 to 20.0 mm, preferably 2.0 to 15.0 mm, and particularly preferably 2.0 to 10.0 mm based on the expansion / contraction direction ED. It

Furthermore, as the distance in the orthogonal direction reference, which is determined by the mutual relationship between the adjacent joints 40, 40 in the joints 40, 40 ...
The percentage of the ratio (distance d between the adjacent joints 40, 40) / (distance from one point of the joint to a corresponding point of the adjacent joint: pitch) is 5 to 60%, preferably 10 to 45. %, And particularly preferably 20 to 35%.
When this percentage is excessively high, when applied to a product, the stretching stress in the width direction (stretching direction) is high, and it is difficult to obtain a suitable fitting property as a worn article.
If the percentage is excessively low, it is not possible to exclude the possibility that the joints 40, 40 adjacent to each other in the orthogonal direction LD are continuous in the manufacturing process, and more fundamentally, the anvil and the heating horn that form the joints. This imposes an excessive burden on the equipment and hinders stable operation.
You can

  The shapes of the individual sheet joining portions 40 and the joining holes 31 in the natural length state can be appropriately determined in addition to the rectangle long in the orthogonal direction described above. For example, as shown in FIG. 26 as an example, a convex lens shape (see FIG. 26A), a rhombus shape (see FIG. 26B), a concave lens shape (see FIG. 26C), and an elliptical shape (see FIG. 26D). ), A perfect circle, a triangle, a polygon, a star, a cloud, or any other shape.

  The joining hole 31 mainly relates to the shape of the joining portion 40 (41, 42, 43) and the manufacturing stage or the degree of expansion and contraction.

  When the first sheet layer 20A and the second sheet layer 20B in the sheet joining portion 40 are joined through the joining holes 31 formed in the elastic film 30, at least the first sheet layer 20A and the second sheet layer 20A in the sheet joining portion 40 are joined. It is desirable that the first sheet layer 20A and the second sheet layer 20B are not joined to the elastic film 30 except between the sheet layers 20B.

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

When the first sheet layer 20 </ b> A and the second sheet layer 20 </ b> B are joined at the sheet joining portion 40 through the joining holes 31 of the elastic film 30, the sheet joining portion 40 is formed by material welding. A first welding mode in which the first sheet layer 20A and the second sheet layer 20B are joined only by a large part or a part of the molten solidified material 20m of at least one of the first sheet layer 20A and the second sheet layer 20B (FIG. 27 (a )), The second welding mode in which the first sheet layer 20A and the second sheet layer 20B are joined only by the whole or most of the elastic film 30 in the sheet joining portion 40 or only a part of the molten solidified product 30m (FIG. 27 (FIG. b)) or a third welding mode in which both of them are combined (see FIG. 27 (c)), but the second and third welding modes are preferable. Arbitrariness.
It is particularly preferable that the first sheet layer 20 </ b> A and the second sheet layer 20 </ b> B are partially melted and solidified 20 m, and all or most of the elastic film 30 in the sheet joining portion 40 is melted and solidified 30 m. 20A and the second sheet layer 20B are joined together. In the third welding mode shown in FIG. 29 (b), between the first and second sheet layers 20A and 20B of the melted and solidified fiber material 20m shown in black, the elastic film 30 shown in white is shown. In the first welding mode shown in FIG. 29A, the molten solidified product 30 m is seen, whereas the elastic film is melted and solidified between the fiber molten solidified products 20 m of the first sheet layer 20A or the second sheet layer 20B. I can't see anything.

As in the first adhesive form and the third adhesive form, the first sheet layer 20A and the second sheet layer 20A and the second sheet layer 20B are melted and solidified 20m of most or a part of the first sheet layer 20A and the second sheet layer 20B. When joining the sheet layers 20B, it is preferable that a part of the first sheet layer 20A and the second sheet layer 20B is not melted because the sheet joining portion 40 is not hardened.
In addition, 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 is not melted. Not only the core of the composite fiber but also the central part of the monocomponent fiber remains, but the peripheral part (including not only the sheath of the composite fiber but also the part on the surface layer side of the monocomponent fiber) melts. The fibers do not melt at all, but the remaining fibers melt all or the core remains but the peripheral portion thereof melts.

When the first sheet layer 20A and the second sheet layer 20B are joined using the molten solidified product 30m of the elastic film 30 as an adhesive as in the second welding mode and the third welding mode, the peel strength is high. In the second welding mode, the first sheet layer 20A is provided 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 and the heating temperature at the time of forming the sheet joint 40. It can be manufactured by sandwiching the elastic film 30 between the second sheet layer 20B and the second sheet layer 20B, pressurizing and heating the portion to be the sheet bonding portion 40, and melting only the elastic film 30.
On the other hand, in the third welding mode, 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 and pressurizing and heating the portion to be the sheet bonding portion 40 to melt at least one of the first sheet layer 20A and the second sheet layer 20B and the elastic film 30.
From this point of view, 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. Preferably, the difference between the melting points of the first sheet layer 20A and the second sheet layer 20B and the elastic film 30 is about 60 to 90 ° C. The heating temperature is preferably about 100 to 150 ° C.

  In the second welding form and the third welding form, when the first sheet layer 20A and the second sheet layer 20B are non-woven fabrics, the melted and solidified product 30m of the elastic film 30 has a sheet joining portion as shown in FIG. 28 (c). The first sheet layer 20A and the second sheet layer 20B in 40 may penetrate between fibers throughout the thickness direction, but as shown in FIG. As shown in FIG. 28 (b), the sheet joining portion 40 has a higher flexibility in the form in which the fibers hardly penetrate between the fibers of the first sheet layer 20 </ b> A and the second sheet layer 20 </ b> B.

FIG. 30 shows an example of an ultrasonic sealing device suitable for forming the second welding form and the third welding form. In this ultrasonic sealing device, when the sheet joint 40 is formed, the first sheet layer 20A, between the anvil roll 60 having the protrusion 60a formed in the pattern of the sheet joint 40 on the outer surface and the ultrasonic horn 61, The elastic film 30 and the second sheet layer 20B are fed. At this time, for example, by setting the feeding transfer speed of the upstream elastic film 30 by the feeding drive roll 63 and the nip roll 62 to be lower than the feeding speed of the anvil roll 60 and the ultrasonic horn 61 and thereafter, the feeding drive roll 63 and the nip roll 62. The elastic film 30 is stretched in the MD direction (machine direction, flow direction) to a predetermined stretching rate along the path from the nip position according to (4) to the sealing position according to the anvil roll 60 and the ultrasonic horn 61. The expansion rate of the elastic film 30 can be set by selecting the speed difference between the anvil roll 60 and the feeding drive roll 63, and can be set to, for example, about 300% to 500%. 62 is a nip roll.
The first sheet layer 20A, the elastic film 30, and the second sheet layer 20B fed between the anvil roll 60 and the ultrasonic horn 61 are laminated in this order, and the protrusion 60a and the ultrasonic horn 61 are separated from each other. While applying pressure between them, it is heated by the ultrasonic vibration energy of the ultrasonic horn 61 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 bonding hole 31 is formed in the elastic film 30, and at the same time, the first sheet layer 20A and the second sheet layer 20B are bonded through the bonding hole 31. Therefore, in this case, the area ratio of the sheet joining portion 40 is selected by selecting the size, shape, spacing, the arrangement pattern in the roll length direction and the roll circumferential direction of the protrusions 60a of the anvil roll 60. You can

  Although the reason why the joining hole 31 is formed is not necessarily clear, it is considered that the portion of the elastic film 30 corresponding to the protrusion 60a of the anvil roll 60 is melted and separated from the surroundings to open the hole. At this time, the portions of the elastic film 30 between the adjacent joint holes 31 arranged in the expansion / contraction direction ED are separated from the portions on both sides in the expansion / contraction direction by the connection holes 31 as shown in FIGS. 9A and 11A. Since it is cut and loses the support on both sides in the contraction direction, it contracts toward the center side of the contraction direction ED in the range closer to the center of the contraction direction ED within the range in which continuity in the direction perpendicular to the contraction direction can be maintained. Then, the joint hole 31 expands in the expansion / contraction direction ED.

The constituent materials of the first sheet layer 20A and the second sheet layer 20B can be used without any limitation as long as they are sheet-shaped, but it is preferable to use a nonwoven fabric from the viewpoint of air permeability and flexibility. The raw material fiber of the nonwoven fabric is not particularly limited. For example, synthetic fibers such as olefins such as polyethylene and polypropylene, polyesters and polyamides, regenerated fibers such as rayon and cupra, natural fibers such as cotton, and mixed fibers and composite fibers in which two or more of them are used. And the like. Furthermore, the nonwoven fabric may be manufactured by any processing.
Examples of the processing method include known methods such as spun lace method, spun bond method, thermal bond method, melt blown method, needle punch method, air through method, and point bond method. When a non-woven fabric is used, its basis weight is preferably about 10 to 25 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 sheet of material is folded back to face each other. For example, as in the illustrated embodiment, at the waist end 23, the component positioned outside is the second sheet layer 20B, and the folded-back portion 20C that is folded back toward the inner surface at the waist opening edge is the first sheet layer 20A. , The elastic film 30 is interposed therebetween, and in the other parts, the inner component is the first sheet layer 20A, and the outer component is the second sheet layer 20B, and the elastic film 30 is interposed therebetween. Can be intervened. 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 LD, and the constituent material of the first sheet layer 20A and the second sheet are provided without folding back the constituent material. The elastic film 30 may be interposed between the constituent materials of the layer 20B.

  The elastic film 30 is not particularly limited, and as long as it is a thermoplastic resin film having elasticity in itself, not only a non-perforated film but also a film having a large number of holes or slits formed for ventilation can be used. . In particular, the tensile strength in the width direction WD (stretching direction ED, MD direction) is 8 to 25 N / 35 mm, the tensile strength in the front-rear direction LD (direction LD, CD direction orthogonal to the stretching direction) is 5 to 20 N / 35 mm, width direction. It is preferable that the elastic film 30 has a tensile elongation in WD of 450 to 1050% and a tensile elongation in the front-rear direction LD of 450 to 1400%. The thickness of the elastic film 30 is not particularly limited, but is preferably about 20 to 40 μm.

(Flexible area)
The region of the exterior body 20 having the elastic sheet stretchable structure 20X has a stretchable region that can stretch in the width direction WD. In the stretchable region 80, the elastic film 30 has a linearly continuous portion (for example, a region indicated by reference numeral 32 in FIG. 12) along the width direction WD, and the stretchable force of the elastic film 30 causes the elastic film 30 to move in the width direction WD. It is contractible and can be expanded in the width direction WD. More specifically, in a state where the elastic film 30 is stretched in the width direction WD, the elastic film 30 of the elastic film 30 is spaced at intervals in the width direction WD and the front-rear direction LD (direction LD orthogonal to the expansion and contraction direction) orthogonal thereto. The first sheet layer 20A and the second sheet layer 20B are joined through the joining holes 31 to form a large number of sheet joining portions 40, thereby forming the elastic sheet stretchable structure 20X and at the stretchable region 80, the elastic film 30. Such stretchability can be imparted by arranging the joining hole 31 so that has a portion 32 that is linearly continuous along the width direction WD.

  In the natural length state, the stretchable region swells in a direction in which the first sheet layer 20A and the second sheet layer 20B between the sheet joining portions 40 are separated from each other, and a shrinking wrinkle 26 extending in the front-rear direction LD is formed, and the width direction WD. Even in the mounted state in which the contraction wrinkles 26 are extended to some extent, the contraction wrinkles 26 are extended but remain.

  It is desirable that the elastic limit elongation of the stretchable region 80 in the width direction WD is 200% or more (preferably 265 to 295%). The elastic limit elongation of the stretchable region 80 is substantially determined by the elongation rate of the elastic film 30 at the time of manufacturing, but on the basis of this, the elastic limit elongation decreases due to the factor that inhibits the contraction in the width direction WD. The main factor of such obstruction is the ratio of the length L of the sheet bonding portion 40 per unit length in the width direction WD, and the elastic limit elongation decreases as the ratio increases. In a normal case, the length L of the sheet joint 40 has a correlation with the area ratio of the sheet joint 40, so that the elastic limit elongation of the stretchable region 80 can be adjusted by the area ratio of the sheet joint 40.

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

  As described above, since the elastic limit elongation and the elongation stress of the stretchable region 80 can be adjusted by the area of the sheet joint 40, as shown in FIG. Can be provided, and the fit can be changed according to the site. In the form shown in FIG. 7, the area 81 of the seat joint portion 40 in the region 81 extending obliquely along the base of the leg in the front body F and the edge region 82 of the leg opening has a higher area ratio of the sheet joint portion 40 than in the other regions. Therefore, the tensile stress is weak and the region is flexible. Further, 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 have a low elongation stress and are flexible. Has become.

(Non-stretchable area)
As shown in FIG. 7, a non-stretchable region 70 can be provided in at least one width direction side of the stretchable region 80 in a region having the elastic sheet stretchable structure 20X in the exterior body 20. The arrangement of the stretchable region 80 and the non-stretchable region 70 can be appropriately determined. In the case of the exterior body 20 of the pants-type disposable diaper as in the present embodiment, since the portion overlapping with the absorber 13 is a region that does not require expansion and contraction, a part or all of the portion overlapping with the absorber 13 as shown in the figure. It is preferable that the non-stretchable region 70 is (which preferably includes almost the entire inner and outer fixed regions 10B). Of course, the non-stretchable region 70 may be provided from the region overlapping with the absorber 13 to the region not overlapping with the absorber 13 positioned in the width direction WD or the front-rear direction LD, and the non-stretching region only in the region not overlapping with the absorber 13. 70 may be provided.

The non-stretchable region 70 is a region in which the elastic film 30 is continuous in the width direction WD, but does not have a linearly continuous portion along the width direction WD due to the presence of the bonding hole 31. Therefore, in a state where the elastic film 30 is stretched in the width direction WD, the first sheet layer 20A and the first sheet layer 20A and the first sheet layer 20A and the first sheet layer 20A are provided at intervals in the width direction WD and the front-rear direction LD orthogonal thereto. Even if the entire elastic sheet stretchable structure 20X including both the stretchable region 80 and the non-stretchable region 70 is formed by joining the two sheet layers 20B and forming the multiple sheet joining portions 40, in the non-stretchable region 70, Since the elastic film 30 is not linearly continuous along the width direction WD, the contraction force of the elastic film 30 hardly acts on the first sheet layer 20A and the second sheet layer 20B, the stretchability is almost lost, and the elastic limit is reached. The elongation is close to 100%.
In such a non-stretchable region 70, the first sheet layer 20A and the second sheet layer 20B are joined by a large number of sheet joining portions 40 arranged at intervals, and the sheet joining portions 40 are not continuous. , Deterioration of flexibility is prevented.

The arrangement pattern of the bonding holes 31 in the elastic film 30 in the non-stretchable region 70 can be appropriately determined.
The area ratio of the sheet joint portions 40 in the non-stretchable region and the area of the individual sheet joint portions 40 can be appropriately determined. However, 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 due to the low area ratio of the joint portion 40.
Area of the sheet joining portion 40: 0.10 to 0.75 mm ² (especially 0.10 to 0.35 mm ² )
Area ratio of the sheet bonding portion 40: 4 to 13% (especially 5 to 10%)

  In the above example, an elastic film is used as the elastic sheet. However, elastic nonwovens can also be used. Further, it is possible to provide an elastic nonwoven fabric on one side or both sides of the elastic film and interpose it between the 1st sheet layer 20A and the 2nd sheet layer 20B.

<Explanation of terms in the specification>
The following terms in the description have the following meanings unless otherwise specified.
-"Front body" and "rear body" mean the front and rear portions of the pants-type disposable diaper with the front-rear center as the boundary. In addition, the crotch portion means a front-rear direction range including the center in the front-rear direction of the pants-type disposable diaper, and when the absorbent body has a constricted portion, it means a front-rear direction range of a portion having the constricted portion.
-"Elastic limit elongation" means the elongation of the elastic limit in the stretching direction ED (in other words, the state where the first sheet layer and the second sheet layer are completely developed), and the length at the elastic limit is the natural length. Is expressed as a percentage, where is 100%.
The “area ratio” means the ratio of the target portion to the unit area, and the target portion (for example, the sheet bonding portion 40, the opening of the bonding hole 31, the ventilation hole) in the target region (for example, the stretchable region 80, the non-stretchable region 70). ) Is the total area divided by the area of the target region and is expressed as a percentage. In particular, the "area ratio" in a region having a stretchable structure means the area percentage in the stretched direction ED to the elastic limit. To do. In the form in which a large number of target portions are provided at intervals, it is desirable to set the target region to a size such that 10 or more target portions are included and obtain the area ratio.
-"Elongation rate" means a value when the natural length is 100%.
-"Basis weight" is measured as follows. After pre-drying the sample or test piece, the sample or test piece is left in a test room or apparatus in a standard condition (test place temperature: 23 ± 1 ° C., relative humidity: 50 ± 2%) to make a constant weight. Pre-drying refers to making a sample or a test piece a constant weight in an environment of a temperature of 100 ° C. The fiber having the official moisture regain of 0.0% does not need to be pre-dried. Using a template (100 mm × 100 mm) for sampling, a sample having a size of 100 mm × 100 mm is cut out from the test piece in a constant weight state. The weight of the sample is measured and multiplied by 100 to calculate the weight per 1 square meter, which is used as the basis weight.
-The "thickness" of the absorber is the thickness measuring device (Peacock, large dial thickness gauge type, model J-B (measuring range 0 to 35 mm) or model K-4 (measuring range 0 to 50 mm)) manufactured by Ozaki Mfg. Co., Ltd. Using, the sample and the thickness measuring device are made horizontal and the measurement is performed.
-"Thickness" other than the above is automatically measured using an automatic thickness meter (KES-G5 handy compression measurement program) under the conditions of load: 0.098 N / cm ² and pressure area: 2 cm ² .
-"Tensile strength" and "tensile elongation (elongation at break)" conform to 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 spacing (distance between marked lines) is 50 mm, and the pulling speed is 300 mm / min. As the tensile tester, for example, AUTOGRAPH AGS-G100N manufactured by SHIMADZU can be used.
-"Elongational stress" refers to a tensile test according to JIS K7127: 1999 "Plastics-Test method for tensile properties-", in which the initial chuck interval (mark distance) is 50 mm and the tensile speed is 300 mm / min. Means a 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, a test piece is formed with a width that can be cut out, and the measured value is 35 mm wide. The value converted to. Further, even when the target area is small and sufficient test pieces cannot be collected, at least comparison is possible as long as the test pieces of the same size are used, even if the test pieces are appropriately small, as long as the magnitude of the elongation stress is compared. . As the tensile tester, for example, AUTOGRAPH AGS-G100N manufactured by SHIMADZU can be used.
-The "deployed state" means a state in which it is flatly deployed without contraction or slack.
-The dimensions of each part refer to the dimensions in the expanded state, not in the natural length state, unless otherwise specified.
-If there is no description about the environmental conditions in the test or measurement, the test or measurement shall be performed in the test room or the equipment in the standard condition (test place is temperature 23 ± 1 ° C, relative humidity 50 ± 2%). To do.

  The present invention, as long as it has a stretchable region to which an elastic sheet stretchable structure can be applied, in addition to pants-type disposable diapers such as the above examples, various disposable diapers such as tape type and pad type, sanitary napkins, swimming and It can be used for all disposable wearing articles such as disposable wearing articles for playing in water.

  DESCRIPTION OF SYMBOLS 10 ... Inner body, 10B ... Inner / outer fixed area, 11 ... Top sheet, 12 ... Liquid impermeable sheet, 13 ... Absorber, 13N ... Constricted portion, 14 ... Packaging sheet, 17 ... Non-absorbent body side part, 20 ... Exterior body , 20A ... First sheet layer, 20B ... Second sheet layer, 20C ... Folded portion, 20X ... Elastic sheet elastic structure, 21 ... Side seal part, 23 ... Waist end part, 24 ... Waist part elastic member, 25F, 25f ... Shrinkage wrinkles, 26 ... Shrinkage wrinkles, 29 ... Leg line, 30 ... Elastic film, 31 ... Joining hole, 33 ... Vent hole, 40 ... Sheet joining part (first joining part), 41 ... Second joining part, 42 ... Third joint portion, 43 ... Fourth joint portion, 70 ... Non-stretchable area, 80 ... Stretchable area, 90 ... Three-dimensional gather, 93 ... Falling portion, 94 ... Free portion, 95 ... Gather sheet, 96 ... Gather elastic member, B … Back body, E ... stretching direction (width direction), F ... front body, L ... intermediate portion, LD ... orthogonal direction (longitudinal direction), T ... waist portion.

Claims (4)

An elastic sheet is interposed between a breathable first sheet layer and a breathable second sheet layer, and the first sheet layer and the second sheet layer are arranged at a plurality of intervals to form a sheet joint. In addition, the elastic sheet stretchable structure is joined through a joining hole penetrating the elastic sheet or through the elastic sheet,
The elastic region showing the elastic sheet elastic structure can be expanded and contracted in the elastic direction by the elastic force of the elastic sheet,
The joint portion is formed with a joint portion row at intervals along a direction orthogonal to the expansion and contraction direction,
A large number of the joining portion rows are formed at intervals in the expansion and contraction direction,
A third joint portion row is formed between the first joint portion row and the second joint portion row which are adjacent to each other,
The interval of at least a part of the third joint portion row in the orthogonal direction is longer than the distance in the orthogonal direction in the first joint portion row and the second joint portion row on both sides of the third joint portion row. ,
The joint portion of the third joint portion row is aligned with the joint portion of at least one of the joint portion of the first joint portion row and the joint portion of the second joint portion row which are adjacent to each other in the expansion and contraction direction, and a joint portion row group is formed. An elastic member characterized by forming intersecting rows across it.   The joint portion of the third joint portion row forms an intersecting row that is aligned with the joint portion of the first joint portion row and the joint portion of the second joint portion row that are adjacent to each other in the expansion and contraction direction and that intersects the joint portion row group. The expansion / contraction member according to claim 1.   The stretchable member according to claim 2, wherein the intersecting rows are formed as a plurality of rows at intervals in the orthogonal direction. An integrated exterior body extending from the front body to the back body, or an exterior body separately provided on the front body and the back body, and an interior body attached to the widthwise middle portion of the exterior body extending over the front and rear sides of the crotch area. The side seal part in which both sides of the exterior body in the front body and both sides of the exterior body in the back body are respectively joined, a waist opening, and a pair of left and right leg openings are provided. A pants-type disposable wearing article having the elastic member according to item 1,
The outer body of at least one of the front body and the back body is such that the elastic member extends and contracts in the width direction over the width direction range corresponding to the side seal portions in at least a part of the front-back direction. Is provided in
A pants-type disposable wearing article having an elastic member.

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