JP7169759B2 - Pants type disposable wearing article - Google Patents

Description

TECHNICAL FIELD The present invention relates to a pants-type disposable wearing article having an elastic structure in which an elastic sheet is sandwiched between a first sheet layer and a second sheet layer.

Disposable wearing articles such as disposable diapers are generally provided with stretchability around the legs and around the waist in order to improve the fit to the body surface. Conventionally, as a method for imparting elasticity, a method of attaching an elongated elastic member such as rubber thread while being stretched in its longitudinal direction has been widely adopted. employs a mode in which the thread rubbers are arranged side by side at intervals in the width and fixed. In addition, as a method for providing an even better fit as a surface, a method of attaching an elastic sheet in a state of being stretched in the direction of imparting elasticity has also been proposed, including those of the present applicant. (See Patent Document 1, for example).

The stretchable structure using the elastic film (hereinafter also referred to as the elastic sheet stretchable structure) is formed by laminating an elastic film between a first sheet layer whose stretchable region is made of nonwoven fabric and a second sheet layer made of nonwoven fabric, and The first sheet layer and the second sheet layer are separated from each other in the direction of stretching and the direction orthogonal thereto (the "front-to-rear direction" of the disposable wearing article) in a state in which the elastic films are stretched in the stretching direction along their surfaces. A large number of spot-like sheet joints are arranged at intervals and are joined through joint holes penetrating the elastic film.
In such an elastic sheet stretchable structure, since the elastic film shrinks between the sheet joints in the natural length state, the gap between the sheet joints becomes narrower, and the sheet joints of the first sheet layer and the second sheet layer Contraction wrinkles extending in a direction intersecting with the stretching direction are formed.
On the other hand, during elongation, as the elastic film stretches between the sheet joints, the gap between the sheet joints and the contraction wrinkles in the first sheet layer and the second sheet layer widen, and the first sheet layer and the second sheet layer expand. It is possible to elastically extend to the fully deployed state. This elastic sheet stretchable structure is not only excellent in surface fitting properties, but also has no surface bonding between the first sheet layer and the second sheet layer and the elastic film. Since there are very few joints, it is very flexible, and there is an advantage that the joint holes of the elastic film also contribute to the improvement of air permeability in the thickness direction.

On the other hand, as shown in Patent Literature 1, the elastic structure can be suitably adopted for a pants-type disposable wearing article.

Japanese Patent No. 5967736 JP 2015-204982 A

In general, pants-type disposable diapers are also desired to fit the wearer like cloth pants.
However, in a pants-type disposable wearing article using an elastic sheet, although it stretches in the width direction, it has poor stretchability in the front-rear direction. Because the side of the waist is difficult to stretch in the front-back direction, the edge of the waist opening on the back body side slides down and is misaligned with the wearer's waist, exposing the skin in the upper buttock area, which is unsightly and may cause urine leakage. have a nature.

Therefore, the main object of the present invention is to provide a pants-type disposable wearing article that can prevent or suppress slippage of the edge of the waist opening on the back body side when the wearer bends forward while wearing the pants-type disposable wearing article. That's what it is.

An aspect of the underpants-type disposable wearing article of the present invention that solves the above problems is
An integrated outer body extending from the front body to the back body, or an outer body provided separately on the front body and the back body, and an inner body attached to the middle part in the width direction of the outer body and extending over both front and rear sides of the crotch part. , a pants-type disposable wearable article comprising a side seal portion in which both sides of the exterior body of the front body and both sides of the exterior body of the back body are respectively joined, a waist opening, and a pair of left and right leg openings. ,
An elastic sheet is interposed between the first sheet layer and the breathable second sheet layer, and the first sheet layer and the second sheet layer are arranged with a gap in the width direction and the front-rear direction. Equipped with an elastic sheet elastic structure that is joined at point-like joints by wearing,
The joint has a first joint and a second joint,
The first joints form a plurality of first joint rows arranged at intervals in the front-rear direction,
The second joints form a plurality of second joints arrayed at intervals in the front-rear direction,
The second joint row is formed between the adjacent first joint rows, and is spaced apart from the first joint rows on both sides in the width direction,
the second joint has an area smaller than that of the first joint, the distance in the front-rear direction of the second joint is longer than the distance in the front-rear direction of the first joint;
Within the length range T in the front-back direction corresponding to the full length of the side seal portion, in the adjustment range Y of 40% or more of the length range T in the front-back direction of the back body, in the width direction of the first joint row is characterized by satisfying the following condition.
[In the central range W1 of 40% or more of the widthwise range W to which the inner body is attached, between the widthwise spacing SM of the first joint portion rows and the widthwise range W and each of the side seal portions The width direction spacing SS of the first joint portion row in the side portion range W2 of the is SM>SS. ]

Within the central range W1, the widthwise spacing of the joints can be longer on the widthwise central side of the disposable wearing article and shorter on the widthwise outer side.

Further, with respect to the above aspect, in the side area W2, the widthwise interval of the first joint portion row can be longer on the widthwise central side of the disposable wearing article and shorter on the widthwise outer side.

Further, with respect to the above aspect, in the side portion range W2, the upper "width-direction arrangement interval of the joint portion group" can be longer than the lower "width-direction arrangement interval of the joint portion group".

According to the present invention, when wearing a pants-type disposable wearing article, it is possible to prevent or suppress slippage of the edge of the waist opening on the side of the back body when the wearer bends forward.
As a result, it is possible to prevent or suppress the unsightly exposure of the skin in the upper region of the buttocks, and to suppress the cause of urinary leakage.

Fig. 2 is a plan view (inner surface side) of the underpants-type disposable diaper in an unfolded state; 1 is a plan view (outer surface side) of a pants-type disposable diaper in an unfolded state; FIG. FIG. 2 is a plan view showing only the essential parts of the underpants-type disposable diaper in an unfolded state; (a) is a cross-sectional view taken along line CC of FIG. 1, and (b) is a cross-sectional view taken along line EE of FIG. FIG. 2 is a cross-sectional view taken along the line AA of FIG. 1; FIG. 2 is a cross-sectional view taken along the line BB of FIG. 1; Fig. 10 is a plan view (inner surface side) of a stretchable region of the pants-type disposable diaper in an unfolded state; (a) is a cross-sectional view corresponding to line CC of FIG. 1, and (b) is a cross-sectional view corresponding to line EE of FIG. FIG. 2 is a plan view and a cross-sectional view showing a joint arrangement disclosed in Patent Document 1; FIG. 4 is a plan view showing a joint arrangement disclosed in Patent Document 2; FIG. 4 is a plan view showing a joint arrangement as a reference example for explanation; 1A is a plan view and FIG. 1B is a cross-sectional view taken along the line BB, showing a first embodiment of the joint arrangement of the present invention. FIG. FIG. 4 is a plan view showing a second embodiment of the joint arrangement of the present invention; FIG. 11 is a plan view showing a third embodiment of the joint arrangement of the present invention; FIG. 11 is a plan view showing a fourth embodiment of the joint arrangement of the present invention; FIG. 11 is a plan view showing a fifth embodiment of the joint arrangement of the present invention; FIG. 11 is a plan view showing a sixth embodiment of the joint arrangement of the present invention; FIG. 11 is a plan view showing a seventh embodiment of the joint arrangement of the present invention; FIG. 12 is a plan view showing an eighth embodiment of the joint arrangement of the present invention; FIG. 12 is a plan view showing a ninth embodiment of the joint arrangement of the present invention; FIG. 10 is a plan view showing a tenth embodiment of the joint arrangement of the present invention; FIG. 11 is a plan view showing an eleventh embodiment of the joint arrangement of the present invention; It is a top view which shows the joint part shape of this invention. FIG. 4 is a cross-sectional view showing an example of a bonding form at a bonding portion of the present invention; FIG. 4 is an explanatory cross-sectional view showing an example of a bonding form; FIG. 10 is a plan view showing an example of a bonding form; 1 is a schematic diagram of an ultrasonic sealing device for manufacturing an elastic member; FIG. FIG. 10 is a side view of the wearer wearing the pants-type disposable diaper and standing up. FIG. 4 is a side view of the wearer wearing the pants-type disposable diaper and bending forward. Fig. 2 is a plan view of the underpants-type disposable diaper in an unfolded state, viewed from the outer surface side; FIG. 2 is a plan view of the underpants-type disposable diaper in an unfolded state as seen from the outer surface side, showing a first example of formation pattern of the joint group according to the present invention. FIG. 10 is a plan view of the underpants-type disposable diaper in an unfolded state as seen from the outer surface side, showing a second example of formation pattern of the joint portion group according to the present invention. FIG. 10 is a plan view of the underpants-type disposable diaper in an unfolded state as seen from the outer surface side, showing a third example of formation pattern of the joint portion group according to the present invention.

An embodiment of the present invention will be described in detail below with reference to the accompanying drawings. Note that the dotted pattern portion in the cross-sectional view indicates a bonding means such as a hot-melt adhesive.
1 to 6 are illustrations of the underpants-type disposable diaper of the present invention. LD (longitudinal direction) indicates the front-rear direction, and WD (ED) indicates the width direction (stretching direction).

This pants-type disposable diaper (hereinafter also simply referred to as a diaper) has an outer body 20 forming a front body F and a back body B, and an inner body 10 fixed and integrated to the inner surface of the outer body 20. The inner 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 inner body 10 is joined to the inner surface (upper surface) of the outer body 20 by a joining means such as a hot-melt adhesive, the inner body 10 and the outer body 20 are joined to the front body F and the back body B. By folding at the center of the front-back direction LD (longitudinal direction), which is the boundary of the waist opening and the left and right It becomes a pants-type disposable diaper in which a pair of leg openings are formed.

(Example of internal body structure)
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. The top sheet 11 absorbs and retains the excreted fluid that has permeated through the top sheet 11 . Although the planar shape of the interior body 10 is not particularly limited, it is generally rectangular as shown in FIG.

As the liquid-permeable top sheet 11 covering the front side (skin side) of the absorbent body 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, and polyamides, as well as recycled fibers such as rayon and cupra, and natural fibers such as cotton. , spunbond method, thermal bond method, meltblown method, needle punch method, etc. can be used. Among these processing methods, the spunlace method is superior in flexibility and drapeability, and the thermal bond method is superior in that it is 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 is excellent. The liquid-permeable top sheet 11 extends to the back side of the absorbent body 13 by wrapping around the side edges of the absorbent body 13 .

The liquid-impermeable sheet 12 covering the back side (non-skin-contacting side) of the absorbent body 13 is made of a liquid-impermeable plastic sheet such as polyethylene or polypropylene. is preferably used. This water-impermeable/moisture-permeable sheet is a microporous sheet obtained by, for example, forming a sheet by melt-kneading an inorganic filler in an olefin resin such as polyethylene or polypropylene, and then stretching the sheet in a uniaxial or biaxial direction. be.

The absorber 13 is a known one, for example, a pile of pulp fibers, an aggregate of filaments such as cellulose acetate, or a non-woven fabric, which is optionally mixed or fixed with a superabsorbent polymer. can be used. The absorber 13 can be wrapped with a liquid-permeable and liquid-retaining wrapping sheet 14 such as crepe paper, if necessary, for shape and polymer retention.

The absorber 13 has a substantially hourglass shape with a constricted portion 13N narrower than the front and rear sides in the crotch portion. The size of the constricted portion 13N can be appropriately determined, but 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 its narrowest portion 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, if the planar shape of the inner body 10 is substantially rectangular, a portion of the inner body 10 corresponding to the constricted portion 13N of the absorbent body 13 does not have the absorbent body 13. Absorber side portions 17 are formed.

The liquid-impermeable sheet 12 is folded back on both sides in the width direction of the absorbent body 13 together with the liquid-permeable top sheet 11 . As the liquid-impermeable sheet 12, it is desirable to use an opaque sheet so that the brown color of feces and urine does not appear. For opacification, a film obtained by internally adding a pigment or 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 gathers 90 include a fixing portion 91 fixed to the side portion of the back surface of the inner body 10, and the inner body 10 extending from the fixing portion 91 to the side of the inner body 10. and the front and rear ends of the body portion 92 are fixed to the side portions of the surface of the interior body 10 (the top sheet 11 in the illustrated form) in a fallen state. It has a portion 93 and a free portion 94 between which the lying portion 93 is not fixed. Each of these parts is formed by a gather sheet 95 formed by folding a sheet of nonwoven fabric or the like into a double sheet. The gathered sheet 95 is attached over the entire front-to-rear direction of the inner body 10 , the fallen portions 93 are provided on the front and rear sides of the non-absorbent side portion 17 , and the free portions 94 are on both front and rear sides of the non-absorbent side portion 17 . extended. Also, between the double gather sheets 95, an elongated gather elastic member 96 is disposed at the tip of the free portion or the like. The gather elastic member 96 is for raising the free portion 94 by elastic contraction force as shown in FIG. 5 in the product state.

In the form shown in FIGS. 5 and 6, the gather elastic member 96 is adhesively fixed to the gather sheet 95 via a hot-melt adhesive at the position of the gather elastic member 96 except for the non-stretchable portion 97, and the gather sheet 95 However, in the lodging non-stretchable portion 97, there is no hot-melt adhesive at the position of the gathering elastic member 96, so the gathering elastic member 96 and the gathering sheet 95 are not bonded, and the gathering elastic The facing surface of the gather sheet 95 is not joined at the position where the member 96 is provided.

The three-dimensional gathers 90 shown in FIGS. 5 and 6 have a form in which the main body portion 92 is not folded.

Materials such as styrene rubber, olefin rubber, urethane rubber, ester rubber, polyurethane, polyethylene, polystyrene, styrene butadiene, silicone, and polyester can be used for the gather elastic member 96 . Also, in order to make it difficult to see from the outside, it is preferable to set the thickness to 925 dtex or less, the tension to 150 to 350%, and the interval to 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 filament-like one shown in the figure.

As with the liquid-permeable top sheet 11, the raw material fibers constituting the gather sheet 95 are synthetic fibers such as olefins such as polyethylene or polypropylene, polyesters, and polyamides, recycled fibers such as rayon and cupra, and cotton. and other natural fibers, and nonwoven fabrics obtained by appropriate processing methods such as spunbonding, thermal bonding, meltblowing, and needle punching can be used. It is preferable to use a nonwoven fabric having a low basis weight and excellent air permeability. Furthermore, the gather sheet 95 is coated with a silicone, paraffin metal, or alkylchromic chloride water repellent agent to prevent permeation of urine and the like, prevent rashes, and improve the touch (dry feeling) to the skin. It is desirable to use a water-repellent nonwoven fabric coated with

As shown in FIGS. 3 to 6, the rear surface of the inner body 10 is joined to the inner surface of the outer body 20 at the inside/outside fixed area 10B (hatched area) with a hot-melt adhesive or the like. The inside/outside fixing region 10B can be determined as appropriate, 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 exterior body 20. FIG.

(Structure example of exterior body)
The exterior body 20 extends outward from the side edge of the absorbent body 13 . In the crotch portion of the outer body 20, the side edge of the outer body 20 may be positioned more centrally in the width direction than the side edge of the inner body 10, as in the illustrated embodiment, or may be positioned on the outer side in the width direction. In addition, the outer body 20 is the front-rear direction range between the waist portion T corresponding to the side seal portion 21 and the waist portion T of the front body F and the waist portion T of the back body B. a middle portion L;

In the illustrated embodiment of the exterior body 20, except for the middle portion in the front-rear direction of the middle portion L, as shown in FIGS. , an elastic sheet, for example, an elastic film 30 is interposed, and as shown in FIG. It has an elastic sheet elastic structure 20X joined through a joint hole 31 penetrating the film 30 .
In the form of application to the diaper, the elastic sheet (elastic film 30 in the example of FIG. 9) stretches and contracts ED in the width direction WD of the diaper.

The first sheet layer 20</b>A and the second sheet layer 20</b>B may be indirectly joined via the elastic film 30 instead of through the joining holes 31 of the elastic film 30 . The planar shape of the exterior body 20 is formed by concave leg circumference lines 29 so that the width direction side edges of the intermediate portion L form leg openings, respectively, and the overall shape resembles an hourglass. The outer body 20 may be formed separately from the front body F and the back body B, and the two may be arranged so as to be separated from each other in the front-rear direction LD of the diaper at the crotch portion.

The configuration shown in FIGS. 1 and 2 is a configuration in which the elastic sheet elastic structure 20X extends to the waist edge 23. However, if the elastic sheet elastic structure 20X is used for the waist edge 23, the waist edge 23 can be stretched. If necessary, such as insufficient tightening, the elastic sheet stretchable structure 20X is not provided at the waist end 23 as shown in FIGS. Structures can also be provided. 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 LD, and provides elastic force so as to tighten the circumference of the body. The waist elastic members 24 are not arranged substantially as a bundle with close intervals, but three or more at intervals of about 3 to 8 mm in the front-rear direction so as to form a predetermined elastic zone. , preferably five or more. Although the elongation rate of the waist elastic member 24 when fixed can be determined as appropriate, it can be about 230 to 320% in the case of normal adult use. In the illustrated example, the waist elastic member 24 uses thread rubber, but other elongated stretchable members such as flat rubber may be used. Although not shown, an elastic film 30 may be provided at the waist end 23 and an elongated waist elastic member 24 may be provided at a position overlapping with the elastic film 30 to form a stretchable structure with both elastic members. In the illustrated embodiment, the edge portion of the leg opening in the exterior body 20 is not provided with an elongated elastic member extending along the leg opening. An elongated elastic member may be provided instead of the elastic film 30 of the part.

As another form (not shown), an intermediate 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 the elastic sheet elastic structure 20X. An elastic sheet stretchable structure 20X is continuously provided in the front-rear direction LD from the inside of the waist portion T of F to the inside of the waist portion T of the back body B through the intermediate portion L, or either the front body F or the back body B. Appropriate modification such as provision of the elastic sheet expansion structure 20X only in the upper part is also possible.

(Form of junction)
Here, various examples of the form of the joint will be described.
FIG. 9 is shown in Patent Document 1 as a representative example.
That is, the joints 40 are arranged in a zigzag arrangement, and the joints 40 are elongated in a direction orthogonal to the stretching direction (that is, the front-rear direction), and are symmetrical with respect to a center line passing through the center of the stretching direction (FIG. 9A). ), the width 40x of the joint 40 in the direction of expansion and contraction is preferably 0.2 to 0.4 mm, the interval d1 between the joints 40 arranged in the direction of expansion and contraction is 3 to 12.9 mm, More preferably, it is 5 to 6.4 mm, and the interval d2 between the joints 40 arranged in the direction orthogonal to the stretching direction (front-rear direction) is 2 to 10.5 mm, more preferably 2.3 to 4.6 mm. is.
In this way, the joints 40 with a remarkably narrow width 40x in the stretching direction are arranged in a zigzag pattern with a relatively wide spacing d1 in the stretching direction, and the contractive force of the elastic film 30 is applied directly to each joint 40. As a result, the arrangement and spacing of the joints 40 at the positions of the joint holes 31 of the elastic film 30 are firmly maintained, and as a result, the flexibility is less likely to decrease. In addition, the folds 25f extend almost straight in the stretching direction and the front-rear direction, and the joints 40 are hidden between the folds 25f and become inconspicuous. As a result, the elastic sheet stretchable structure 20X has an appearance closer to cloth while suppressing a decrease in flexibility.

On the other hand, although the joints 40 are arranged in a staggered arrangement, if the joints 40 are circular, the joints 40 can be clearly seen between the folds 25f of the wrinkles and the folds 25f. , the pleats 25f extend in the direction perpendicular to the stretching direction (front-rear direction) so as to largely wrap around the joint 40, so that the overall wavy folds 25f are formed, and there is a tendency that a fabric-like appearance cannot be obtained. .

From this point of view, it is desirable that the shape of the joint 40 is elongated in a direction perpendicular to the expansion/contraction direction (front-rear direction). However, if the maximum length of the joint 40 in the direction perpendicular to the stretching direction (front-rear direction) is too short or too long, the straightness of the pleats 25f may be reduced or the flexibility may be reduced. . Therefore, although these dimensions can be determined as appropriate, the length 40y of the joint 40 in the direction orthogonal to the expansion/contraction direction (the front-rear direction) is 0.4 to 3.2 mm, particularly 0.7 to 1.4 mm. is preferred.

On the other hand, in Patent Document 2 (Japanese Patent Application Laid-Open No. 2015-204982), in both the two examples shown in FIGS. It is also staggered, and in the example of (b), the small circular sub-joints are arranged between the rectangular main openings. The example (b) is also based on the concept of staggered arrangement.
The arrangement and dimensions of each opening are preferably within the dimension range (unit: mm) shown in FIG.

Both inventions of Patent Documents 1 and 2 disclose vertically elongated openings and also disclose a staggered arrangement.
However, in both the inventions of Patent Documents 1 and 2, since the distance between the openings of the elastic film in the direction perpendicular to the stretching direction (the front-rear direction) is set large, the stretching stress in the stretching direction is high. Not a few wearers feel that the underpants-type disposable diaper is excessively tightened (in the width direction).
Here, in Patent Document 2, it is preferable that the opening length B shown in FIG.
When calculating the percentage of (distance between adjacent first joints) / (distance from one point of the joint to the corresponding point of the adjacent first joint), it is (0.3 to 0.7 mm )/(0.6 to 1.4 mm)=21.4 to 183%, and although the calculated lower limit is small, it seems that a large value is actually assumed.

On the other hand, as shown in FIG. 11, the distance between the openings of the elastic film in the direction (front-rear direction) perpendicular to the stretching direction WD (ED) (the vertical direction in the drawing: the direction of symbol LD) is reduced. With this setting, the stretching stress in the stretching direction can be reduced, so that when applied to an underpants-type disposable diaper, it is possible to gently fit the wearer with a weak tightening force.
The reason for this is that the openings open in the width direction to form joining holes 31 as shown in FIG. Even if it is stretched in the width direction, there are no openings in the spaced-apart regions perpendicular to the stretching direction between the sections. It is believed that there is.

In the form shown in FIG. 11, in addition to being able to fit the wearer gently, the area ratio occupied by the joints and the area ratio occupied by the joint holes in the state of use extended in the width direction are high, so it is excellent in breathability. It also brings the advantage of
However, in the usage pattern of the product shown in FIG. 11( a ), the row of joints 40 , 40 . Wrinkles along the orthogonal direction (front-rear direction) LD are formed in the spaced-apart regions between adjacent rows of joint portions 40, 40, . . . . As shown in FIG. 11(b), this wrinkle 25F is simply a uniform mountain shape. That is, it differs from the cross section shown in US Pat.
When the form shown in FIG. 11 is viewed from the design point of view of the entire stretchable region of the product, long wrinkles 25F in the orthogonal direction (front-back direction) LD are formed in the stretch direction ED (WD) in a uniform repetition. , the design is likely to be simple, and the appeal of the product is small.

Embodiments of particularly preferred joints will be sequentially described below with representative examples.

<First embodiment>
In the elastic member according to the first embodiment shown in FIG. 12, an elastic sheet is interposed between the first sheet layer having air permeability and the second sheet layer having air permeability, and the first sheet layer and the second sheet layer The layers comprise an elastic sheet elastic structure joined at a number of spaced sheet joints through joint holes passing through the elastic sheet or via said elastic sheet.
Further, the stretchable region indicating the stretchable structure of the elastic sheet can be stretched in the stretching direction by the contractile force of the elastic sheet.
In the present invention, the joint portion has first joint portions 40, 40, . . . and second joint portions 41, 41, .

The first joints 40, 40, .
As will be described later with reference to FIG. 19, for example, as an eighth embodiment, the rows of the first joints 40 do not follow the orthogonal direction (front-rear direction) LD, and the angle θ intersecting with the expansion/contraction direction ED is 30 degrees or more. It is desirable that the slope is in the range of 150 degrees (thus not including 90 degrees), more preferably in the range of 45 degrees to 135 degrees (not including 90 degrees).
In the first embodiment, the non-inclined crossing angle θ is 90 degrees.

The first joint portion 40 is formed with a length L of 0.3 to 7.0 mm, preferably 0.5 to 5.0 mm, and particularly preferably 0.7 to 2.5 mm in the orthogonal direction (front-back direction) LD standard. be done.
In addition, the first joint portions 40, 40 ... rows have a formation pitch S0 of 2.0 to 20.0 mm, preferably 3.0 to 15.0 mm, particularly preferably 4.0 to 4.0 mm, based on the expansion and contraction direction ED (WD). It is formed with 10.0 mm.

Furthermore, as the distance in the orthogonal direction (front-back direction) LD standard determined by the mutual relationship of the adjacent first joints 40, 40 in the first joints 40, 40 ... row,
(Distance d between adjacent first joints)/(Distance P from one point of the joint to the corresponding point of the adjacent first joint) is 5 to 60%, preferably 10 to 45%, preferably 20-35%.
If this percentage is excessively high, when applied to a product, the stretch stress in the width direction (stretch direction) tends to be high, making it difficult to obtain an appropriate fit as a wearable article.
Also, if the percentage is too low, the possibility that the first joints 40, 40 adjacent to each other in the orthogonal direction (front-rear direction) LD become continuous during the manufacturing process cannot be ruled out. The anvils and heating horns to be formed impose an excessive load on the equipment, and may become a cause of disturbing stable operation.

It is desirable that no joints longer than the length L of the first joints 40 be formed in the row of the second joints 41 , 41 . Also from this point of view, the embodiment is completely different from the embodiment of FIG.

The above-described first embodiment typically exhibits the following advantages or features.
(1) Since the percentage R is low, the stretchable sheet member has a low stretching stress in the stretching direction and has a soft elongation.
Moreover, since the opening ratio is increased, the air permeability is increased.
(2) Not only the rows of the first joints 40, 40, but also the rows of the second joints 41, 41, . Inter-row pleats R can be formed between the rows.
(3) Since the second joint 41 has a smaller area than the first joint 40, it looks like a pattern.
(4) The inter-row pleats R can be formed between the first joint portions 40, 40 . . . row and the second joint portions 41, 41 . , 40 . . . , two inter-row pleats can be formed. However, since the interval between the second joints 41, 41 is long in the second joints 41, 41, . As a result, as compared with the case where inter-row pleats are formed only by the first joint portions 40, 40, . . . , as shown in FIG.
Thus, the area of contact with the wearer's skin is reduced, improving comfort and improving softness.

<Second embodiment>
As shown in FIG. 13, the second joint portions 41, 41, . In this case, even if the length L of the first joint portion 40 is short, the position of the second joint portion 41 can reduce the expansion and contraction stress.

<Third embodiment>
As shown in FIG. 14, the second joints 41 are not adjacent to the first joints 40 in a one-to-one relationship, but for example, two first joints 40 and 40 are provided with one second joint. A configuration in which the portions 41 are arranged adjacently can be employed.

<Fourth embodiment>
As shown in FIG. 15, between the first joint portions 40, 40 . . . row and the second joint portions 41, 41 . can be formed.
The formation of the third joints 42 can form large pleats bf by dividing the inter-row pleats R shown in the first embodiment in the orthogonal direction (front-rear direction) LD.
Small pleats sf can be formed between the third joint 42 and the first joints 40, 40, .
In the pleat group divided by the inter-row pleats R, the bending rigidity of the elastic member is low (easily bendable), and the ability to follow the movement of the body is excellent.

<Fifth embodiment>
As shown in FIG. 16, by obliquely arranging the positions of the third joints 42 together with the second joints 41, it is possible to form a group of obliquely arranged large pleats bf, which enhances the design.

<Sixth embodiment>
As shown in FIG. 17, the fourth joints 43 can be inserted and arranged in the rows of the first joints 40, 40, . In this case, the fourth joints 43, 43, . In this case, the area of the fourth joint portion 43 is preferably 5% or more and 50% or less of the area of the first joint portion 40 .

<Seventh embodiment>
As shown in FIG. 18, the first joint portion 40 itself may be inclined. The second joint portion 41 may also be inclined.
In the present invention, the length of the joint portion is based on the orthogonal direction (front-rear direction) LD, so as shown in FIG. The length of the LD in the orthogonal direction (front-rear direction) is the length of the joint portion.
As for the separation distance, the LD distance in the orthogonal direction (front-rear direction) between the center of the side and the center of the opposite side is the separation distance d.

<Eighth embodiment>
As shown in FIG. 19, both the first joint portion 40 and the second joint portion 41 are inclined, and the row of each joint portion is not along the orthogonal direction (front-rear direction) LD, but is at an angle intersecting with the expansion/contraction direction ED. An example is shown in which θ is inclined in the range of 30 degrees to 150 degrees, preferably 45 degrees to 135 degrees. The crossing angle θ is particularly preferably 60 degrees to 120 degrees. However, these angular ranges indicating inclination do not naturally include 90 degrees.
The advantage that this joint row is not along the orthogonal direction (front-to-rear direction) LD but is inclined to intersect with the stretching direction ED becomes clear when compared with the seventh embodiment shown in FIG. That is, in the example shown in FIG. 19, the distance between, for example, the first joints 40, 40 on the LD line in the orthogonal direction (front-rear direction) is considerably larger than that of the seventh embodiment shown in FIG. is the cause of the

That is, for example, the joining of the first sheet layer 20A and the second sheet layer 20B at the sheet joining portion 40 is preferably performed by a joining means such as heat sealing or ultrasonic sealing, which is material welding.
In the case of continuous production, ultrasonic seal melting is performed between the anvil roll and the ultrasonic horn, but in order to prevent energy loss, the ultrasonic horn is also closely attached to the sheet along the entire axial direction of the anvil roll. For this reason, when forming a pattern with a large proportion of anvil roll projections, such as the rows of joints 40, 40 in FIG. For this reason, if an excessive contact force is applied along the bus lines that are in line contact, the burden on the equipment side is large.
On the other hand, in the case of the eighth embodiment shown in FIG. 19 (generally in the case of the inclined arrangement), the proportion of the joints located on the line of the orthogonal direction (front-rear direction) LD is small, and the line is stable. Since the pressure is high, the equipment burden is small, and stable operation is possible.
In the eighth embodiment shown in FIG. 19, since the first joint portion 40 (and the second joint portion 41) is inclined, it also has the advantage of being able to form folds and pleats with excellent design.

<Ninth embodiment>
In the ninth embodiment shown in FIG. 20, the rows of the first joint portions 40, 40, and the rows of the second joint portions 41, 41, . . .
The arrangement of corrugated curves is aesthetically pleasing.

<Tenth embodiment>
In the tenth embodiment shown in FIG. 21, the large pleats bf are arranged along a wavy curve oscillating in the orthogonal direction (front-rear direction) LD. The arrangement of the wavy curves is also aesthetically pleasing.

<Eleventh embodiment>
In the eleventh embodiment shown in FIG. 22, the first joint portions 40, 40, and the second joint portions 41, 41, 41, 41, . . . It is configured along a waveform curve that swings in the direction (front-rear direction) LD. This arrangement of corrugated curves enables the formation of complex pleats, which is aesthetically pleasing.
Furthermore, embodiments of the present invention will be described.

The shapes of the individual sheet joint portions 40 and the joint holes 31 in the natural length state can be appropriately determined in addition to the rectangular shape described above. For example, as shown in FIG. 23, convex lens shape (see FIG. 23(a)), rhombus shape (see FIG. 23(b)), concave lens shape (see FIG. 23(c)), elliptical shape (see FIG. 23(d)) ), a perfect circle, a triangle, a polygon, a star, a cloud, or any other shape.

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

When the first sheet layer 20A and the second sheet layer 20B are joined at the sheet joining portion 40 through the joining holes 31 formed in the elastic film 30, at least the first sheet layer 20A and the second sheet layer 20B at the sheet joining portion 40 are bonded. 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 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 joining of the first sheet layer 20A and the second sheet layer 20B at the sheet joining portion 40 may be made with a hot-melt adhesive, or may be made with a joining means by material welding such as heat sealing or ultrasonic sealing. .

When the first sheet layer 20A and the second sheet layer 20B are joined through the joining holes 31 of the elastic film 30 at the sheet joining portion 40, 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 melted and solidified material 20m of at least one of the first sheet layer 20A and the second sheet layer 20B (see FIG. 24(a)). )), and a second welding mode in which the first sheet layer 20A and the second sheet layer 20B are joined only by the melted and solidified material 30m of the elastic film 30 in the sheet joining portion 40 (see FIG. 24 ( b)), and a third welding mode (see FIG. 24(c)) in which both of these are combined, but the second and third welding modes are preferred.
Particularly preferably, the first sheet layer 20A and the second sheet layer 20B are partially melted and solidified 20m and all or most of the elastic film 30 at the sheet joint 40 is melted and solidified 30m. 20A and the second sheet layer 20B are joined. In the third welding mode shown in FIG. 26(b), the elastic film 30 shown in white is placed between the melted and solidified fibers 20m of the first sheet layer 20A or the second sheet layer 20B shown in black. While the melted solidified material 30m can be seen, in the first welding mode shown in FIG. can't see anything.

As in the first bonding mode and the third bonding mode, the first sheet layer 20A and the second sheet layer 20B are bonded to each other by using the molten and solidified material 20m of at least one of the first sheet layer 20A and the second sheet layer 20B as an adhesive. When joining the sheet layers 20B, it is preferable not to melt a part of the first sheet layer 20A and the second sheet layer 20B so that the sheet joining portion 40 is not hardened.
When the first sheet layer 20A and the second sheet layer 20B are non-woven fabrics, the core (the core ( Including not only the core in the conjugate fiber but also the central part of the monocomponent fiber) remains, but the surrounding part (including not only the sheath in the conjugate fiber but also the surface layer side part of the monocomponent fiber) is melted, or some Including morphologies in which the fibers are not melted at all, but the remaining fibers are all melted, or the core remains but its surrounding portion melts.

When the first sheet layer 20A and the second sheet layer 20B are joined using the melted and solidified material 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 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 for forming the sheet joint portion 40. and the second sheet layer 20B, pressurize and heat the portion to be the sheet joint portion 40, and melt only the elastic film 30. As shown in FIG.
On the other hand, in the third welding mode, 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 produced by sandwiching the elastic film 30 and applying pressure and heat to the portion that will become the sheet joint 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. is preferable, and the difference between the melting point 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.degree. Also, the heating temperature is preferably about 100 to 150.degree.

In the second welding mode and the third welding mode, when the first sheet layer 20A and the second sheet layer 20B are nonwoven fabrics, the melted and solidified material 30m of the elastic film 30 is formed at the sheet joints as shown in FIG. 25(c). 40 may penetrate between the fibers throughout the thickness direction of the first sheet layer 20A and the second sheet layer 20B, but as shown in FIG. As shown in FIG. 25(b), the flexibility of the sheet joint portion 40 is higher in the form in which the fibers of the first sheet layer 20A and the second sheet layer 20B hardly permeate.

FIG. 27 shows an example of an ultrasonic sealing device suitable for forming the second weld configuration and the third weld configuration. In this ultrasonic sealing device, when forming the sheet joint portion 40, between the anvil roll 60 having projections 60a formed on the outer surface in the pattern of the sheet joint portion 40 and the ultrasonic horn 61, the first sheet layer 20A, The elastic film 30 and the second sheet layer 20B are fed. At this time, for example, by making the feed transfer speed of the upstream elastic film 30 by the feed drive roll 63 and the nip roll 62 slower than the transfer speed after the anvil roll 60 and the ultrasonic horn 61, the feed drive roll 63 and the nip roll 62 The elastic film 30 is stretched to a predetermined elongation rate in the MD direction (machine direction, machine direction) along the path from the nip position by the anvil roll 60 and the ultrasonic horn 61 to the seal position by the ultrasonic horn 61 . The elongation 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 about 300% to 500%, for example. 62 is a nip roll.
The first sheet layer 20A, the elastic film 30 and the second sheet layer 20B sent between the anvil roll 60 and the ultrasonic horn 61 are laminated in this order, and the protrusion 60a and the ultrasonic horn 61 While being pressurized between them, they are heated by the ultrasonic vibration energy of the ultrasonic horn 61 to melt only the elastic film 30, or to melt at least one of the first sheet layer 20A and the second sheet layer 20B and the elastic film 30. By doing so, the joint holes 31 are formed in the elastic film 30 and at the same time, the first sheet layer 20A and the second sheet layer 20B are joined through the joint holes 31 . Therefore, in this case, the area ratio of the sheet joint portion 40 can be selected by selecting the size, shape, spacing of the protrusions 60a of the anvil roll 60, the arrangement pattern in the roll length direction and the roll circumferential direction, and the like. can be done.

Although the reason why the joint 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 melts and separates from the surroundings to form the hole. At this time, as shown in FIGS. 9(a) and 11(a), the portions of the elastic film 30 between the joint holes 31 adjacent to each other in the stretch direction ED are separated from the portions on both sides of the stretch direction by the joint holes 31, as shown in FIGS. Since it is cut and loses the support on both sides in the contraction direction, the center side of the contraction direction ED and the front-back direction LD shrinks until it is balanced toward the center side of the contraction direction within the range where continuity in the contraction direction and the front-back direction can be maintained. 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 particular limitation as long as they are in the form of sheets. The nonwoven fabric is not particularly limited as to what the raw material fibers are. 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 using two or more of these. etc. can be exemplified. Furthermore, the nonwoven fabric may be manufactured by any processing.
Examples of processing methods include known methods such as spunlace, spunbond, thermal bond, meltblown, needle punch, air through, and point bond methods. When a non-woven fabric is used, it is preferable that its basis weight is about 10 to 25 g/m ² . Also, part or all of the first sheet layer 20A and the second sheet layer 20B may be a pair of layers formed by folding one sheet of material and facing each other. For example, as shown in the illustrated embodiment, in the waist end portion 23, the second sheet layer 20B is used as the outer component, and the first sheet layer 20A is used as the folded portion 20C that is folded inward at the waist opening edge. , and the elastic film 30 is interposed therebetween, and in the other portions, the inner constituent material is the first sheet layer 20A, the outer constituent material is the second sheet layer 20B, and the elastic film 30 is interposed therebetween. can intervene. Of course, the constituent members of the first sheet layer 20A and the constituent members of the second sheet layer 20B are separately provided over the entire front-rear direction LD, and the constituent members of the first sheet layer 20A and the second sheet layer 20B are arranged without folding back the constituent members. An elastic film 30 can also be interposed between the components of layer 20B.

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

(stretch area)
A region having the elastic sheet stretchable structure 20X in the exterior body 20 has a stretchable region that is stretchable in the width direction WD. In the elastic region 80, the elastic film 30 has a linearly continuous portion 32 (see FIG. 12(a)) along the width direction WD, and is contracted in the width direction WD by the contractile force of the elastic film 30. It is stretchable in the width direction WD. More specifically, while the elastic film 30 is stretched in the width direction WD, the elastic film 30 is joined at intervals in the width direction WD and the front-rear direction LD (stretching direction and the front-rear direction LD) perpendicular to the width direction WD. By joining the first sheet layer 20A and the second sheet layer 20B through the holes 31 to form a large number of sheet joining portions 40, the elastic sheet stretchable structure 20X is formed, and the elastic film 30 is formed in the stretchable region 80. Such stretchability can be imparted by arranging the joint holes 31 so as to have a linearly continuous portion 32 (see FIG. 12(a)) along the width direction WD.

As shown in FIGS. 9 and 12(b), the stretchable region swells in the direction in which the first sheet layer 20A and the second sheet layer 20B between the sheet joints 40 separate from each other in the natural length state. Shrink wrinkles 25f and 25F extending in the direction LD are formed, and even in the mounted state in which it is stretched to some extent in the width direction WD, the shrink wrinkles 25F are stretched but remain. Further, as shown in the illustrated embodiment, the first sheet layer 20A and the second sheet layer 20B are not bonded to the elastic film 30 at least at the sheet bonding portion 40 other than between the first sheet layer 20A and the second sheet layer 20B. , FIG. 9(c), which assumes the mounted state, and FIG. 9(a), which assumes the unfolded state of the first sheet layer 20A and the second sheet layer 20B, in these states, the elastic film 30 A gap is formed between the joint hole 31 and the sheet joint portion 40 , and even if the material of the elastic film 30 is a non-porous film or sheet, this gap adds breathability. Further, in the natural length state, further contraction of the elastic film 30 narrows the joint hole 31 , so that almost no gap is formed between the joint hole 31 and the sheet joint portion 40 .

It is desirable that the elastic limit elongation in the width direction WD of the elastic region 80 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 manufacture, but based on this, it decreases due to factors that inhibit contraction in the width direction WD. The main factor of such a hindrance is the ratio of the length L of the sheet joint portion 40 per unit length in the width direction WD, and the larger the ratio, the lower the elastic limit elongation. Normally, the length L of the sheet joints 40 has a correlation with the area ratio of the sheet joints 40 , so the elastic limit elongation of the elastic region 80 can be adjusted by the area ratio of the sheet joints 40 .

The extension stress of the stretchable region 80 is mainly due to the LD distance (separation distance d) in the orthogonal direction (front-rear direction) of the portion 32 (see FIG. 12A) where the elastic film 30 is linearly continuous along the width direction WD. It can be adjusted by summation.

The area ratio of the sheet joints 40 in the stretchable region 80 and the area of each individual sheet joint 40 can be determined as appropriate, but in normal cases, it is preferable to set them within the following range.
Area of sheet joint 40: 0.14 to 3.5 mm ² (especially 0.14 to 1.0 mm ² )
Area ratio of sheet joint 40: 1.8 to 19.1% (especially 1.8 to 10.6%)

In this way, since the elastic limit elongation and elongation stress of the elastic region 80 can be adjusted by the area of the sheet joint portion 40, as shown in FIG. can be provided to change the fit depending on the part. In the form shown in FIG. 7, an edge elastic region 82 of the leg opening is provided. It is an area that expands and contracts.

(Non-stretch area)
A non-stretchable region 70 can be provided on at least one widthwise side of the stretchable region 80 in the region having the elastic sheet stretchable structure 20X in the exterior body 20, as shown in FIG. The arrangement of the stretchable regions 80 and the non-stretchable regions 70 can be determined as appropriate. In the case of the outer body 20 of the underpants-type disposable diaper as in the present embodiment, the portion overlapping the absorbent body 13 is a region that does not require expansion and contraction. (It is desirable to include substantially the entire inner/outer fixing region 10B) as the non-stretchable region 70 . Of course, the non-stretchable region 70 can be provided from the region overlapping the absorbent body 13 to the region not overlapping the absorbent body 13 located in the width direction WD or the front-rear direction LD, and only the non-stretchable region in the region not overlapping the absorbent body 13. 70 can also be provided.

The non-stretchable region 70 is defined as a region where 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 existence of the joining holes 31 . Therefore, in a state in which the elastic film 30 is stretched in the width direction WD, the first sheet layer 20A and the second sheet layer 20A and the second sheet layer 20A and the second sheet layer 20A are separated from each other through the joining holes 31 of the elastic film 30 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 regions 80 and the non-stretchable regions 70 is formed by bonding the two sheet layers 20B and forming a large number of sheet joints 40, the non-stretchable regions 70: Since the elastic film 30 is not linearly continuous along the width direction WD, the contractile 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 and the elastic limit is reached. 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 joints 40 arranged at intervals, and the sheet joints 40 are not continuous. , the loss of flexibility is prevented.

The arrangement pattern of the joint holes 31 in the elastic film 30 in the non-stretchable region 70 can be determined appropriately.
The area ratio of the sheet joints 40 in the non-stretchable region and the area of the individual sheet joints 40 can be determined as appropriate. It is preferable that the non-stretchable region 70 does not become rigid due to the low area ratio of the joint 40 .
Area of sheet joint 40: 0.10 to 0.75 mm ² (especially 0.10 to 0.35 mm ² )
Area ratio of sheet joint 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. Alternatively, an elastic nonwoven fabric may be provided on one or both sides of the elastic film and interposed between the first sheet layer 20A and the second sheet layer 20B.

<Description 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" refer to the front and rear portions of the underpants-type disposable diaper, respectively, with respect to the center in the front-rear direction. In addition, the crotch part means the front-rear direction range including the front-rear direction center of the pants-type disposable diaper, and means the front-rear direction range of the portion having the constricted part when the absorbent body has the constricted part.
・"Elastic limit elongation" means the elongation at the elastic limit (in other words, the state in which the first sheet layer and the second sheet layer are completely unfolded) in the stretching direction ED, and the length at the elastic limit is the natural length. is expressed as a percentage when the is 100%.
・"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 opening of the joint hole 31, the ventilation hole ) is expressed as a percentage by dividing the total area of the target area by the area of the target area. Especially, the “area ratio” in the area having a stretchable structure means the area ratio in the state stretched to the elastic limit in the stretch direction ED. It is something to do. In a form in which a large number of target portions are provided at intervals, it is desirable to determine the area ratio by setting the target region to a size that includes 10 or more target portions.
- "Elongation rate" means a value when the natural length is taken as 100%.
- "Matsuke" is measured as follows. After pre-drying the sample or test piece, it is left in a test room or apparatus under standard conditions (test location: temperature 23±1° C., relative humidity 50±2%) to a constant weight. Pre-drying refers to making a sample or test piece constant weight in an environment at a temperature of 100°C. Fibers with an official moisture content of 0.0% do not need to be pre-dried. Using a sampling template (100 mm x 100 mm), a sample with dimensions of 100 mm x 100 mm is cut from the constant weight specimen. The weight of the sample is measured, multiplied by 10 to calculate the weight per square meter, and used as the basis weight.
・The "thickness" of the absorber is measured by Ozaki Seisakusho Co., Ltd.'s thickness measuring instrument (Peacock, dial thickness gauge large type, model JB (measuring range 0 to 35 mm) or model K-4 (measuring range 0 to 50 mm)). Measure by placing the sample and the thickness gauge horizontally.
• "Thickness" other than the above is automatically measured using an automatic thickness gauge (KES-G5 handy compression measurement program) under the conditions of a load of 0.098 N/cm ² and a pressurized area of 2 cm ² .
・ "Tensile strength" and "tensile elongation (breaking elongation)" are in accordance with JIS K7127: 1999 "Plastics - Test method for tensile properties -" except that the test piece is a rectangular shape with a width of 35 mm and a length of 80 mm. means a value measured with an initial chuck interval (distance between gauge lines) of 50 mm and a tensile speed of 300 mm/min. As a tensile tester, for example, AUTOGRAPH AGS-G100N manufactured by SHIMADZU can be used.
・"Elongational stress" is determined according to JIS K7127:1999 "Plastics - Tensile property test method -" by a tensile test with an initial chuck interval (marked line distance) of 50 mm and a tensile speed of 300 mm / min. , 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 subject. 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. converted to In addition, even if the target area is small and sufficient test pieces cannot be collected, if the magnitude of the tensile stress is compared, it is possible to at least compare even small test pieces as long as the test pieces of the same size are used. . As a tensile tester, for example, AUTOGRAPH AGS-G100N manufactured by SHIMADZU can be used.
- "Unfolded state" means a flat unfolded state without contraction or slack.
・Unless otherwise specified, the dimensions of each part mean the dimensions in the unfolded state, not in the natural length state. In particular, the dimensions of the joints are the dimensions in the fully developed state (the state before the first sheet layer and the second sheet layer are broken), and substantially match the joint pattern dimensions on the anvil roll.
・If there is no description about environmental conditions for testing and measurement, the test and measurement shall be performed in a laboratory or equipment under standard conditions (test location: temperature 23±1°C, relative humidity 50±2%). do.

<Joint interval of the back body>
To provide a pants-type disposable wearing article capable of preventing or suppressing slippage of the edge of the waist opening on the back body side when the wearer bends forward while wearing the pants-type disposable wearing article.

As described above, an underpants-type disposable diaper in which an elastic sheet (particularly an elastic film) is used and the front body F and the back body B are joined by the side seal portions 21 expands and contracts in the width direction but not in the front-rear direction. Because of the poor stretchability of the waist, when the standing state of FIG. 28 changes to the forward bending state of FIG. It may be misaligned with the wearer's waist, resulting in unsightly exposed skin in the upper buttock area and a possible cause of urine leakage.

In the present invention, as shown in FIG. 30, for example, in the back body, the arrangement interval of the joint portions in the width direction is devised for the adjustment range Y within the length range T in the front-rear direction corresponding to the full length of the side seal portions 21. It is what I did.

For the length of the adjustment range Y, it is not appropriate to set a preferable range as an absolute value because the sizes of diapers for adults and children are completely different, and the length of the adjustment range Y is 40% or more of the length range T in the front-rear direction. The adjustment range Y is defined as a range, more preferably a length range of 70% or more.
If the adjustment range Y is short, it is insufficient to prevent the edge of the waist opening on the side of the back body B from slipping down.
If necessary, it is possible to set the "interval between joint portions in the width direction" according to the present invention to the trailing edge of the elastic film 30 . Moreover, when the waist elastic member is not provided as shown in FIGS. 1 and 2, the adjustment range Y may be formed to the vicinity of the waist opening.

Here, the "disposition interval in the width direction of the group of joints" according to the present invention will be explained in advance. In addition to the joint portion 40 having one shape as shown in FIG. 11, if a joint portion 41 having another shape exists between the joint portions 40 and 40 as shown in FIG. The joint portion 40 is determined, and the interval between the joint portions 40, 40 is defined as the arrangement interval.
The reason for this is that the expansion and contraction between the joints 40 and 40 predominantly expands and contracts without being influenced by the existence of the joint 41 having other shapes. Further, in the embodiment of FIG. 11, the formation pitch S0 is the "arrangement interval of the joint portion group in the width direction".
In the joint pattern examples shown in FIGS. 13 to 22, it is possible to similarly set the "width-direction arrangement interval of the joint group". Except for the example in FIG. 19, the reference numerals for the "width-direction arrangement intervals of the joint portions" are omitted.

FIG. 31 shows a first formation pattern example of the joint group. In this example, the central range W1 within the widthwise range W to which the inner body 10 is attached, and the side range W2 between the side seal portion 21 and the widthwise range W are two types of "joint portion group". Layout interval in the width direction” is defined.

As an annotation here, it is not appropriate to set preferred ranges as absolute values for the width direction range W, the central range W1, and the armpit range W2 because, for example, diaper sizes for adults and children are completely different.
Since the width of the inner body 10 is selected according to the product size as well as the relative value to the full width of the diaper in the unfolded state, the central range W1 is the relative value to the "width direction range W in which the inner body is attached". and the armpit range W2 can be set.

That is, the central range W1 is a length range of 40% or more, more preferably 70% or more of the widthwise range W where the inner body 10 is attached. The reason why the central range W1 is defined in relation to "the widthwise range W in which the inner body is attached" is that the inner body 10 includes a slightly rigid absorbent body, and is spaced from the inner body 10 in the front-rear direction. However, since the area is not highly stretchable in the width direction, it is based on the idea of increasing the stretchability of that area.
In the present invention, the setting of the armpit range W2 is not limited.

Under these conditions, as shown in FIG. 31, the first formation pattern example of the joint group is as follows.
Within the length range T in the front-back direction corresponding to the full length of the side seal portion 21, the width direction of the joint portions 40, 40 group in the adjustment range Y having a length of 40% or more of the length range T in the front-back direction of the back body B , the arrangement interval satisfies the following conditions.
Width direction spacing SM between the joints 40, 40 and side portions between each of the side seal portions 21 and the width direction range W in the central range W1 of 40% or more of the width direction range W to which the inner body 10 is attached The widthwise interval SS between the joints 40, 40 in the range W2 is SM>SS.

FIG. 32 shows a second formation pattern example of the joint group. In this example, the central range W1 within the widthwise range W to which the inner body 10 is attached, and the side range W2 between the side seal portion 21 and the widthwise range W are two types of "joint portion group". In addition to defining the arrangement interval in the width direction, a transition region having an intermediate "arrangement interval in the width direction of the joint group" is formed from the central range W1 to the side area W2, and a total of three types of "joints It defines the "arrangement interval in the width direction of the group".
As can be inferred from this example, more transition regions can be used to connect the central region W1 and the side regions W2, if desired.

FIG. 33 shows a third formation pattern example of the joint group. In this example, the "intervals of joint portions in the width direction" are made different between the upper portion and the lower portion within the side portion range W2.
In this case, it is desirable that the upper "width-direction arrangement interval of the joint portion group" is longer than the lower "width-direction arrangement interval of the joint portion group".
In the specific example shown in FIG. 33 , the diagonal dividing line Z from the center in the width direction to the outside is used as a rough boundary, and the upper “width direction arrangement interval of the joint portion group” is the lower “width of the joint portion group”. It is made longer than the “direction arrangement interval”.

According to these formation pattern examples of the joint portion group, it is possible to prevent or suppress slippage of the edge of the waist opening on the back body side when bending forward.
That is, even if the diaper stretches in the width direction but lacks stretchability in the front-rear direction, in the armpit area W2, since the "width-direction arrangement interval SS of the group of joints" is short, the diaper fits strongly to the wearer. do. On the other hand, in the central range W1, since the "widthwise arrangement interval SM of the joint portion group" is long, it fits the wearer rather weakly.
Therefore, in the central range W1, the extent to which the wearer's skin stretches when the wearer bends forward from the standing state is low. It is possible to prevent or suppress slippage of the edge.

As long as it has a stretchable region to which the elastic sheet stretchable structure can be applied, the present invention can be applied to various disposable diapers such as tape type and pad type, sanitary napkins, swimming It can be used for general disposable wearing articles such as disposable wearing articles for playing in water.

DESCRIPTION OF SYMBOLS 10... Inner body, 10B... Inner-outer fixing area, 11... Top sheet, 12... Liquid-impermeable sheet, 13... Absorbent body, 13N... Constricted part, 14... Packaging sheet, 17... Non-absorbent side part, 20... Exterior body 20A First sheet layer 20B Second sheet layer 20C Folded portion 20X Elastic sheet elastic structure 21 Side seal portion 23 Waist edge 24 Waist elastic member 25F, 25f Shrink wrinkles 29 Leg circumference line 30 Elastic film 31 Joining hole 33 Ventilation hole 40, 40A, 40B Sheet joining portion (first joining portion) 41 Second joining portion 42 Second 3 joints, 43... fourth joint, 50, 50a... tearing limit part, 70... non-stretchable area, 80... stretchable area, 82... edge stretchable area, 90... three-dimensional gather, 93... fallen portion, 94...free Part 95... Gathered sheet 96... Gathered elastic member B... Back body ED... Elastic direction (width direction) F... Front body L... Intermediate part LD... Orthogonal direction (front-back direction) T... Waist circumference , W1 . . . central range, W2 .. side portion range, SM .

Claims (4)

An integrated outer body extending from the front body to the back body, or an outer body provided separately on the front body and the back body, and an inner body attached to the middle part in the width direction of the outer body and extending over both front and rear sides of the crotch part. , a pants-type disposable wearable article comprising a side seal portion in which both sides of the exterior body of the front body and both sides of the exterior body of the back body are respectively joined, a waist opening, and a pair of left and right leg openings. ,
An elastic sheet is interposed between the first sheet layer and the breathable second sheet layer, and the first sheet layer and the second sheet layer are arranged with a gap in the width direction and the front-rear direction. Equipped with an elastic sheet elastic structure that is joined at point-like joints by wearing,
The joint has a first joint and a second joint,
The first joints form a plurality of first joint rows arranged at intervals in the front-rear direction,
The second joints form a plurality of second joints arrayed at intervals in the front-rear direction,
The second joint row is formed between the adjacent first joint rows, and is spaced apart from the first joint rows on both sides in the width direction,
the second joint has an area smaller than that of the first joint, the distance in the front-rear direction of the second joint is longer than the distance in the front-rear direction of the first joint;
Within the length range T in the front-back direction corresponding to the full length of the side seal portion, in the adjustment range Y of 40% or more of the length range T in the front-back direction of the back body, in the width direction of the first joint row is characterized by satisfying the following condition.
[In the central range W1 of 40% or more of the widthwise range W to which the inner body is attached, between the widthwise spacing SM of the first joint portion rows and the widthwise range W and each of the side seal portions The width direction spacing SS of the first joint portion row in the side portion range W2 of the is SM>SS. ] 2. The underpants-type disposable wearing article according to claim 1, wherein, in said central range W1, the widthwise interval of said first joint row is longer on the widthwise central side of the disposable wearing article and shorter on the widthwise outer side of the disposable wearing article. 2. The underpants-type disposable wearing article according to claim 1, wherein in said side portion range W2, the widthwise interval of said first joint portion row is long on the widthwise central side of the disposable wearing article and short on the widthwise outer side thereof. 2. The disposable underpants-type according to claim 1, wherein, in said armpit area W2, an upper "widthwise interval of said second joint row" is longer than a lower "widthwise interval of said second joint row". worn articles.

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