JP5124188B2 - Disposable diapers - Google Patents

Description

  The present invention relates to a paper diaper, and more particularly to a pants-type paper diaper having an expansion / contraction part in which an elastic expansion / contraction member is arranged on a waist part.

For example, in a pants-type paper diaper that is an absorbent article, as shown in FIGS. 1 and 6, a shearing S may be formed around the abdomen and waist as an expansion / contraction part in order to add a fitting function (for example, Patent Documents). 1). This shearing S sandwiches elastic elastic members 2, 2,..., Such as thread rubber, with an exterior sheet 1 formed by laminating and fixing two or three breathable / water-repellent nonwoven fabrics, and elastic elastic members 2, 2,. The elastic elastic members 2, 2,... And the exterior sheet 1 are intermittently fixed with an adhesive such as hot melt and the elastic elastic members 2, 2,. Is. In FIG. 1, WO indicates a waist opening, and LO indicates a leg opening.
As a known technique for fixing the elastic elastic members 2, 2,... To the sheet 1 such as the nonwoven fabric, either the elastic elastic members 2, 2,. In general, an adhesive such as hot melt is applied to both the outer sheet 1 and the exterior sheet 1 and then fixed by niping the elastic elastic members 2, 2,.
Further, in recent years, an anvil roll (not shown) that is intermittently arranged and is constituted by a protrusion that becomes an adhesive surface, and a heat fusion device (not shown) arranged at a position facing the anvil roll (not shown). In addition, a technique for continuously supplying the elastic stretchable members 2, 2,... Between the sheets 1 and fixing the exterior sheet 1 and the elastic stretchable members 2, 2,. Yes.
JP 2002-172132 A JP 2004-330777 A

However, when a hot melt adhesive is used, the adhesive strength of the adhesive is kept constant, resulting in complicated manufacturing equipment such as temperature control of the adhesive and not being applied to elastic elastic members such as rubber. In addition, since the adhesive is applied to manufacturing equipment such as a pressure roll and a transfer belt, there is a risk of causing machine troubles such as increasing the resistance of the sliding portion of the manufacturing equipment and mixing of foreign substances into the product. In addition, there is a problem that mechanical parts are deteriorated or the ambient temperature is increased by heat (150 to 200 ° C.) for dissolving the hot melt.
On the other hand, an adhesive other than hot melt is not preferable because a volatile solvent is harmful to the human body or it is fluid at room temperature and cannot exhibit sufficient adhesive strength.
Moreover, when the elastic stretchable member and the nonwoven fabric (exterior sheet) are fixed with an adhesive to form the stretchable portion as a paper diaper product, there is a problem that the breathability and softness of the stretchable portion are lost.
Furthermore, in the method of fixing in the pinched state of the invention described in Patent Document 2, there is a problem that the elastic stretchable member such as rubber is deteriorated and the strength and stretchability of the elastic stretchable member are lowered.
As described above, the stretchable portion forming method has not only the above-described problems, but also the stretchability of the conventional pant-type paper diaper has room for improvement in air permeability, softness, stretchability, and the like.
Then, the main subject of this invention is providing the paper diaper which fixed the elastic elastic member and the exterior sheet | seat, without using an adhesive agent in an expansion-contraction part, and improved air permeability, softness, stretchability, etc.

The present invention that has solved the above problems is as follows.
<Invention of Claim 1>
The invention according to claim 1 includes an exterior sheet having an inner layer and an outer layer, and an absorption portion that is provided on the body side of the exterior sheet and absorbs and holds an object.
A paper diaper having a stretchable part in which a plurality of elastic stretchable members arranged in parallel are sandwiched between the inner layer and the outer layer in the waistline part,
With the tensile force applied to the elastic elastic member , the inner layer and the outer layer are intermittently welded in the supply direction in the vicinity of both sides in the diameter direction of the elastic elastic member,
Thereafter, in the cross-sectional space closed by the welded portion between the inner layer and the outer layer, the elastic elastic member is released with a tensile force to increase the cross-sectional outer diameter of the elastic elastic member. The elastic part was formed by fixing the elastic elastic member to the sheet by the frictional force between the outer surface and the layer sheet forming the closed space,
It is a paper diaper characterized by that.

<Invention of Claim 2>
The invention according to claim 2 includes an exterior sheet having an inner layer and an outer layer, and an absorption portion that is provided on the body side of the exterior sheet and absorbs and holds an object.
A paper diaper having a stretchable part in which a plurality of elastic stretchable members arranged in parallel are sandwiched between the inner layer and the outer layer in the waistline part,
Wherein while applying a tensile force to the resilient and elastic members, the side portions overlapping the sides and near the resilient and elastic members in the diametrical direction of the resilient and elastic members, and said inner and outer layers intermittently to the feed direction Welded,
Thereafter, in the cross-sectional space closed by the welded portion between the inner layer and the outer layer, the elastic elastic member is released with a tensile force to increase the cross-sectional outer diameter of the elastic elastic member. The elastic part was formed by fixing the elastic elastic member to the sheet by the frictional force between the outer surface and the layer sheet forming the closed space, and the joining force with the sheet at the side part,
It is a paper diaper characterized by that.

<Invention of Claim 3>
According to a third aspect of the present invention, the elastic elastic member is configured in a net shape by a plurality of elastic yarns arranged in parallel and a plurality of elastic yarns orthogonal to the elastic yarns. The paper diaper described.

(Function and effect)
The stretchable part is welded with a predetermined distance between the inner layer and the outer layer in the vicinity of both sides in the diameter direction of the elastic stretchable member in a state where a tensile force is applied to the elastic stretchable member, so that the elastic stretchable member is mounted on the exterior. By setting it as the structure fixed with the frictional force with a sheet | seat, deterioration by an adhesive agent can be prevented. Moreover, since the elastic elastic member is not bonded, an expansion / contraction part in which air permeability and softness are ensured can be formed. The welding can be ultrasonic welding or heat welding. However, it is more preferable to use ultrasonic welding because the influence of heat and pressure on the elastic stretchable member and the outer periphery of the exterior sheet is less than that of ultrasonic welding.
In addition, the elastic expansion / contraction member is formed by welding the elastic expansion / contraction member with a predetermined interval between the both sides in the diameter direction of the elastic expansion / contraction member and the inner layer and the outer layer in a state where a tensile force is applied to the elastic expansion / contraction member. Is fixed to the exterior sheet by the frictional force with the exterior sheet and the adhesive force of the both sides in the diametrical direction of the elastic expansion / contraction member, in addition to the frictional force with the exterior sheet, the end in the width direction of the elastic expansion / contraction member The elastic elastic member is more firmly fixed by the adhesive force of the part. In addition, since adhesion is only the end portion in the width direction of the elastic elastic member, there is no risk of deterioration or cutting of the elastic elastic member.
The mechanism in which the elastic elastic member is fixed by the frictional force with the exterior sheet is such that the inner layer and the outer layer are intermittently provided in the vicinity of both end portions in the width direction of the elastic elastic member with a tensile force applied to the elastic elastic member. If the load is removed thereafter (no tension), the outer diameter of the cross section of the elastic expansion / contraction member increases, and the inner layer and the outer layer are more elastic. A pressing force is applied so as to sandwich the elastic member from both sides in the diameter direction . As a result, the elastic elastic member is fixed only by the frictional force with the sheet without fixing the elastic elastic member with an adhesive.
As an elastic expansion-contraction member, you may use what was comprised by the net shape by the some elastic yarn arrange | positioned in parallel, and the some elastic yarn orthogonal to these.

<Invention of Claim 4>
The invention according to claim 4 is the paper diaper according to any one of claims 1 to 3, wherein the welding is constituted by ultrasonic welding or heat welding .

<Invention of Claim 5>
Invention of Claim 5 is a paper diaper of any one of Claims 1 thru | or 4 by which the said elastic elastic member is cut | disconnected or not provided in the part which overlaps with the said absorption part in the said exterior sheet | seat. is there.

<Invention of Claim 6>
According to a sixth aspect of the present invention, at least one end in the longitudinal direction of the elastic stretchable member is welded and fixed to the elastic stretchable member and the inner layer and the outer layer of the exterior sheet by a welding line that vertically cuts the elastic stretchable member. It is a paper diaper of any one of Claims 1 thru | or 5 which is a structure.

(Function and effect)
By adopting a configuration in which the inner layer and the outer layer in the stretchable part are bonded together by ultrasonic welding or heat welding without using an adhesive, the breathability and softness of the stretchable part are further improved.
Moreover, the shrinkage | contraction which acts with respect to an absorption part by setting it as the structure which the back side elastic elastic member and / or abdominal elastic elastic member are cut | disconnected or not provided in the part which overlaps with the absorption part in an exterior sheet | seat. The force becomes weak or disappears, and absorption inhibition due to the contraction of the absorption part is less likely to occur.
Furthermore, at least one end portion in the longitudinal direction of the elastic elastic member is configured such that the elastic elastic member and the inner layer and the outer layer of the exterior sheet are welded and fixed by a welding line that vertically cuts the elastic elastic member arranged in parallel. By doing so, fixing at both end portions in the longitudinal direction of the elastic stretchable member becomes more reliable.

  According to the present invention, the elastic stretchable member and the exterior sheet can be fixed without using an adhesive in the stretchable portion, and the air permeability, softness, stretchability, and the like can be improved.

Embodiments of the present invention will be described below.
<Overall configuration of pants-type disposable diapers>
An example of a pants-type disposable diaper is shown in FIGS. The pants-type disposable diaper 10 includes an exterior sheet 12 constituting an exterior part, and an absorption part 20 fixed to the body side (inner surface side). The absorption part 20 is a part that receives and absorbs excrement such as urine and loose stool (menstrual blood in the case of a sanitary napkin described later), and the exterior sheet 12 is a part for supporting the absorption part 20 to the wearer. It is.

(Exterior sheet)
The exterior sheet 12 includes a front end side portion W, a rear end side portion W, and an intermediate portion L between them, and the front end side portion W and the rear end side portion W are formed as a waistline portion along the waistline of the adherend. In addition, both side edges of the intermediate portion L are formed as leg circumference edges 12E that are constricted along the circumference of the legs of the wearer, and this is a portion into which the wearer's legs are put. As a result, the exterior sheet 12 has a substantially hourglass shape as a whole. Although the absorption part 20 can take arbitrary shapes, in the form of illustration, it is a rectangle. The intermediate portion L of the exterior sheet 12 is not essential and may be configured only by the front end portion W and the rear end portion W.
As shown in FIG. 2, the exterior sheet 12 has the absorption portion 20 installed and fixed at a predetermined position, and its front and rear end portions are folded and fixed on the front end portion and the rear end portion of the absorption portion 20, and then the ventral side 12 </ b> F. Are folded back and forth so that the back side 12B and the back side 12B overlap each other, and the joint regions 12A on both sides of the abdomen 12F and the back side 12B of the exterior sheet 12 are joined by heat fusion, hook material, buttons, fasteners or the like. Thus, the pants-type disposable diaper having the structure shown in FIG. 1 and having a waist opening WO and a pair of leg openings LO is obtained.
In the illustrated example, the width of the intermediate portion of the absorbent portion 20 in the front-rear direction (longitudinal direction, ie, the vertical direction in FIG. 2) is longer than the width connecting the edges around the legs of the exterior sheet 12. However, it may be the same width.
As shown in FIG. 5, the exterior sheet 12 has an elastic elastic member 12 </ b> C between the air permeable outer layer 12 </ b> S and the air permeable inner layer 12 </ b> H in the front end side portion W and the rear end side portion W in the waistline portion. 12C... Are sandwiched in an expanded state, and as described later, both layers 12S and 12H are fixed by ultrasonic welding or heat welding in this state. Thereby, the shearing S is formed in the waist portion. It should be noted that an adhesive such as hot melt may be used in a portion where the elastic elastic members 12C, 12C... Are not provided, but it is preferable that this portion is also fixed by ultrasonic welding or heat welding.
In order to obtain a soft texture, the ratio of the area of the welded portion to the total area in the portion where the elastic elastic members 12C, 12C... Are not provided is preferably 20% or less, and more preferably 10% or less. Moreover, in order to maintain the bonding strength of the outer layer 12S and the inner layer 12H, the ratio of the area of the welded portion is preferably 2% or more.
The outer layer 12S and the inner layer 12H of the outer sheet 12 can be used without any limitation as long as they are breathable materials. However, it is preferable to use a water-repellent nonwoven fabric from the viewpoint of touch and waterproofness. Each of the outer layer 12S and the inner layer 12H may be formed by laminating a plurality of materials. As the non-woven fabric, for example, polypropylene resin (PP), polyethylene resin (PE), polyethylene terephthalate resin (PET), or a composite of these can be used. Furthermore, a film made of polyethylene resin or the like may be sandwiched between the layers of the nonwoven fabric. The thicknesses of the outer layer 12S and the inner layer 12H can be determined as appropriate, but the thickness of the outer layer 12S is preferably equal to or greater than the thickness of the inner layer 12H. The outer layer 12S and the inner layer 12H are each preferably in the range of 5 to 30 g / m ^{2 in} basis weight. The thickness of the outer layer 12S is preferably 5 mm or less, and the thickness of the inner layer 12H is preferably 1 mm or less.

(Elastic elastic member)
The elastic elastic member 12 </ b> C may be made of a known elastic yarn as long as it has elasticity and can be fixed in tension with the surrounding nonwoven fabric. Materials include natural rubber, polyurethane, block polyether amide, block polyether ester, polyurethane urea, elastic polyolefin, thermoplastic styrene-butadiene-styrene (SBS), styrene-isoprene-styrene, styrene-ethylene / propylene-styrene, Styrene-ethylene-butadiene-styrene (SEBS), hydrogenated styrene-butadiene-rubber and elastomers based on these and other polymers such as polystyrene or polyolefins can be used. Also, elastic yarns from segmented polyester or polyether urethane-urea can be used.
The thickness of the elastic elastic member 12C can be arbitrarily set. Further, the cross-sectional shape is not limited to a circle, but can be freely selected from an ellipse, a rectangle, and other geometric shapes.
Furthermore, the elastic elastic member 12C is not limited to a thread-like member, and although not shown, a wide ribbon-like member or a net-like member can be employed. In the case of a ribbon shape, it is preferable that both ends in the width direction are welded to the sheet together with the inner and outer sheets. In the case of the net shape, it is preferable to weld the inner and outer sheets not only on the elastic yarn in the tensile direction but also on the elastic yarn orthogonal to the tensile yarn in the vicinity of both ends in the width direction. In this case, the orthogonal elastic yarn and the welded portion may be separated from each other, but if the welded portion is welded not only to both ends in the width direction of the elastic yarn but also to the central portion, the elastic yarn breaks or the welded portion becomes hard. Since there is a possibility, it is not preferable.
If the elastic elastic member 12C is provided in the entire waist region W, the elastic elastic member 12C itself hits the lower waist region even if the elastic force of the elastic elastic member 12C itself is weak, so that the product fits the wearer suitably.

  As shown in the figure, it is also preferable to cut the dorsal and ventral elastic elastic members 12C, 12C,... It can replace with this and the form which does not provide the back side and the abdominal side elastic elastic members 12C, 12C, ... in the part which overlaps with absorber 56 is also employable. As for this cutting method, as disclosed in Japanese Patent Application Laid-Open No. 2002-178428, a plurality of points may be cut at a predetermined interval in the width direction, or only one point may be cut. As described above, when the elastic elastic member 12C is discontinuous at the portion overlapping the absorber 56, the contraction force acting on the absorber 56 is weakened or eliminated, and the absorption inhibition due to the absorber 56 contracting. Is less likely to occur. Further, only one of the backside and ventral elastic elastic members 12C, the elastic elastic member 12C is discontinuous, only a part of the backside or ventral elastic elastic member 12C is discontinuous, or a combination thereof. Appropriate changes can be made, such as discontinuity of only one part of the elastic elastic member 12C on either the back side or the ventral side.

  Further, in this way, when the elastic elastic member 12C is discontinuous in the portion overlapping the absorber 56, the elastic expansion / contraction member with a high elongation rate is prevented because the narrow expansion / contraction part prevents the slippage during mounting. It is preferable to fix 12C. Specifically, the expansion ratio of the elastic elastic member 12C is preferably 250% or more, and particularly preferably 270% or more. On the other hand, when the elastic stretchable member 12C is not discontinuous in the portion overlapping with the absorbent body 56, the stretch rate of the elastic stretchable member 12C is preferably about 150 to 250%. This is not preferable because the wearer feels uncomfortable.

  Further, when the elastic elastic member 12C is fixed at a high elongation rate, particularly in an extended state of 250% or more, and a discontinuous portion is provided by cutting or the like, the elastic elastic member 12C is contracted strongly, so that the elastic elastic member 12C has a discontinuous portion side. There is a possibility that retraction (a phenomenon in which the elastic elastic member 2 contracts while shifting without being fixed by the sheets 1A and 1B) may occur at the end portion. Such pull-in gradually proceeds with long-time wearing, loosening the tightening around the waist and causing the diaper to fall off. Conventionally, since a large amount of adhesive was used to prevent such a phenomenon, the texture was easily deteriorated. In particular, at an elongation rate of 300% or more, it was difficult to manufacture while suppressing pulling. On the other hand, in the present invention, even if the expansion rate of the elastic elastic member 12C is high, the elastic elastic member 12C is hardly pulled even at an elongation rate of 300% or more, and the amount of adhesive used is drastically reduced. As a result, the texture and breathability are excellent. If the outer layer 12S and the inner layer 12H have low frictional resistance and the elastic member 12C has a high elongation rate, pulling may occur even with the fixing structure of the present invention. By using a small amount of adhesive in combination, it is possible to prevent the pull-in without substantially damaging the texture and air permeability.

(Transparency improvement part)
Although not shown in the drawing, almost all parts other than the part where the elastic elastic member 12C is arranged, that is, almost all except the front and rear edges of the intermediate part L in the front-rear direction of the exterior sheet 12, have the outer layer 12S over the entire width. It is good also as the permeability improvement part 12P which does not have 12H and the elastic elastic member 12C. In this case, the inner layer 12H is individually provided on each of the front end side portion W and the rear end side portion W of the exterior sheet 12, but the inner layers 12H and 12H do not overlap each other. As a result, the air permeability in the crotch part and the part near the crotch where it is easily sultry is drastically improved, and sultry is prevented. Moreover, since there is no hot melt for bonding the inner layer 12H and the outer layer 12S of the exterior sheet 12 in 12P, the softness is also improved. And in this form, 12 C of elastic elastic members are provided over the whole trunk periphery area | region W, and it can aim at prevention of dampness, without reducing fit property. Furthermore, in order to improve air permeability and softness, the outer layer 12S in 12P may be omitted, and the exterior sheet 12 may not be provided in the middle portion L in the front-rear direction. In this case, in the intermediate part L, it is preferable to coat the body fluid impermeable sheet 70 of the absorbent part 20 with a cloth-like material such as a nonwoven fabric. Since it can be freely selected without considering the characteristics related to friction with the elastic elastic member 12C, a material specialized in other physical properties such as texture, softness, and air permeability can be obtained.
The length in the front-rear direction of the permeability improving portion 12P is preferably 30% or more, particularly 35-65% or more of the length in the front-rear direction of the article. Further, in terms of the area ratio of the portion that overlaps the back surface of the absorbing portion 20, the transparency improving portion 12P is configured to overlap 30% or more, particularly 35 to 50%, with respect to the entire back surface of the absorbing portion 20. preferable. From the viewpoint of improving air permeability, the larger the permeability improving portion 12P is, the better. However, if it is excessively large, there is no portion where the elastic elastic member 12C is provided, which may impair the fit.

(Absorption part)
As shown in FIG. 3, the absorbent portion 20 may include a topsheet 30 made of, for example, a nonwoven fabric that allows body fluid to permeate, and an absorbent element 50 in order from the use surface side. In a normal case, a body fluid impermeable sheet (also called a back sheet) 70 made of a plastic sheet or the like is provided on the back side of the absorbent element 50. The back side of the body fluid impermeable sheet 70 is joined to the body side surface of the exterior sheet 12. In addition, an intermediate sheet (also referred to as a second sheet) 40 can be provided between the top sheet 30 and the absorbent element 50 in order to quickly transfer body fluid that has passed through the top sheet 30 to the absorbent element 50. Furthermore, in order to prevent excrement from leaking on both sides of the absorption part 20, barrier cuffs 60, 60 standing on both sides of the absorption part 20 can be provided.

(Top sheet)
The top sheet 30 has a property of transmitting body fluid. Accordingly, the material of the top sheet 30 is sufficient if it exhibits this body fluid permeability, and examples thereof include a porous or non-porous nonwoven fabric and a porous plastic sheet. Of these, the nonwoven fabric is not particularly limited as to what the raw fiber is. For example, the above-described polypropylene resin (PP), polyethylene resin (PE), polyethylene terephthalate resin (PET), or a composite of these can be used. Furthermore, the nonwoven fabric may be manufactured by any processing. Examples of the processing method include known methods such as a spunlace method, a spunbond method, a thermal bond method, a melt blown method, and a needle punch method. For example, if flexibility and drapeability are required, the spunbond method and spunlace method are preferable. If bulkiness and softness are required, the air-through method, point bond method, and thermal bond method are preferable processing methods. .
The top sheet 30 may be composed of a single sheet or a laminated sheet obtained by bonding two or more sheets. Similarly, the top sheet 30 may be composed of one sheet or two or more sheets in the planar direction.

(Intermediate sheet)
In order to quickly transfer the body fluid that has permeated through the top sheet 30 to the absorbent body, an intermediate sheet 40 that is generally referred to as a “second sheet” that has a higher body fluid permeation rate than the top sheet 30 can be provided. The intermediate sheet 40 not only improves the absorption performance by the absorbent body by quickly transferring the body fluid to the absorbent body, but also prevents the “reversal” phenomenon of the absorbed body fluid from the absorbent body, and the top sheet 30 is always dried. It can be made into the state which carried out. The intermediate sheet 40 can be omitted.
Examples of the intermediate sheet 40 include the same materials as the top sheet 30, spunlace, pulp nonwoven fabric, a mixed sheet of pulp and rayon, point bond, or crepe paper. In particular, an air-through nonwoven fabric and a spunbond nonwoven fabric are preferable.
The intermediate sheet 40 in the illustrated form is disposed in the center shorter than the width of the absorber 56, but may be provided over the entire width. The length of the intermediate sheet 40 in the longitudinal direction may be the same as the length of the absorbent body 56 or may be within a short length range centered on the region that receives the body fluid. A typical material for the intermediate sheet 40 is a nonwoven fabric having excellent body fluid permeability.

(Body fluid impermeable sheet)
The body fluid impermeable sheet 70 simply means a sheet disposed on the back surface side of the absorber 56, and in the present embodiment, is a sheet in which the absorber 56 is interposed between the top sheet 30. Therefore, the material of the main body liquid impermeable sheet is not particularly limited. Specifically, for example, an olefin resin such as polyethylene or polypropylene, a laminated nonwoven fabric obtained by laminating a nonwoven fabric on a polyethylene sheet or the like, a nonwoven fabric that substantially ensures liquid impermeability by interposing a waterproof film (in this case, A body fluid impermeable sheet is comprised with a waterproof film and a nonwoven fabric.) Etc. can be illustrated. Of course, in addition to this, materials having liquid impermeability and moisture permeability, which have been used and used in recent years from the viewpoint of preventing stuffiness, can also be exemplified. As the sheet of the material having liquid impermeability and moisture permeability, for example, an inorganic filler is kneaded in an olefin resin such as polyethylene or polypropylene, and the sheet is formed, and then stretched in a uniaxial or biaxial direction. Examples of the microporous sheet obtained in this way can be given.
The body fluid impervious sheet 70 can be prevented from side leakage of body fluid by extending it to the use surface in a so-called forehead form (not shown). This is prevented by interposing a second body fluid impermeable sheet 72 between the double barrier sheets 64 forming 60. According to this embodiment, since the second body fluid impermeable sheet 72 extends until the barrier cuff 60 stands up, the body fluid diffused laterally through the top sheet 30 and the side of the soft stool between the barrier cuffs 60, 60 There is also an advantage that leakage can be prevented.
The bodily fluid impermeable sheet 70 can be provided with a display section for a product name, a function description, a character, a pattern, and the like, and this display section may have a notification function for informing that urination has occurred.

(Barrier cuffs)
Barrier cuffs 60, 60 provided on both sides of the product are provided to prevent urine and soft stool that travel laterally along the top sheet 30 and prevent side leakage. It is.
The illustrated barrier cuff 60 is a doubled water-repellent non-woven sheet, and is formed so as to protrude from the back side of the absorbent body 56 to the lower side of the top sheet 30 and to protrude to the front side. Yes. In order to prevent urine from moving laterally on the top sheet 30, a second body fluid impermeable sheet 72 is interposed between the double barrier sheets 64 forming the barrier cuff 60. Alternatively, a structure may be adopted in which the side portion of the body fluid impermeable sheet 70 is inserted between the double barrier sheets 64 and extends to the middle of the barrier cuff 60 projecting to the surface side.
The shape of the barrier cuff 60 itself can be designed as appropriate. However, in the example shown in the drawing, an elastic elastic member, for example, a rubber thread 62 is fixed to the tip and middle of the protruding portion of the barrier cuff 60 under stretch, The barrier cuff 60 stands up due to the contraction force in use. As shown in FIG. 3, the base side of the barrier cuff 60 is positioned so that the middle rubber thread 62 is positioned at the center side of the front rubber thread 62, 62 and fixed to the front and rear end portions of the top sheet 30. It rises diagonally toward the center side, and the tip part stands up diagonally outward from the intermediate part.

(Absorption element)
The absorbent element 50 includes an absorbent body 56 and a covering sheet 58 that wraps at least the back and side surfaces of the absorbent body 56. The covering sheet 58 can be omitted. Further, in the illustrated embodiment, the holding sheet 80 is provided between the absorber 56 and the back surface side portion (lower part) of the covering sheet 58, but the holding sheet 80 may be omitted.

(Absorber)
As the absorbent body 56, a thing made of an aggregate of filaments 52, 52.

<The stretchable part forming method according to the present invention and a pants-type disposable diaper having the stretchable part>
Now, a stretchable part forming method according to the present invention and a pants-type paper diaper having the stretchable part will be described with reference to FIGS.
As shown in FIG. 7, the stretchable part forming apparatus according to the present invention includes an ultrasonic vibration source 2, a horn 3 that is connected to the ultrasonic vibration source 2 and increases the vibration amplitude from the ultrasonic vibration source 2, And an anvil roll 4 disposed to face the horn 3. The ultrasonic vibration source 2 is fixed to a pressure arm (not shown), and the height can be adjusted. Further, before and after the anvil roll 4, guide rolls 5 and 5 are provided for preventing loosening of the continuous sheet 1 in a state where the elastic elastic members 2, 2,. The continuous sheet 1 is an original sheet of the exterior sheet 12.
Although not shown, in order to prevent loosening of the continuous sheet 1 in a state where the elastic elastic members 12C, 12C,... In order to maintain, it is more preferable to use tension control such as a step roll.

As shown in FIGS. 8 (1) and 8 (2), a plurality of projections 4A, 4A,... Serving as ultrasonic welding surfaces are formed on the outer peripheral surface of the anvil roll 4, and these projections 4A, 4A,. A groove having a predetermined depth is formed between 4A,. The horn 3 and the protrusion 4A of the anvil roll 4 sandwich the continuous sheet 1, and the inner layer 12H and the outer layer 12S of the continuous sheet 1 are welded by the welded portion 11 as shown in FIGS. 9 (1) and (2). However, the groove formed between the protrusion 4A and the protrusion 4A is not fused, and a gap is formed in the folded continuous sheet 1. In the drawing, the inner layer 12H is located at the upper portion and the outer layer 12S is located at the lower portion, but the inner layer 12H may be located at the lower portion and the outer layer 12S may be located at the upper portion. The same applies to this point.
The distance between the protrusion 4A in the width direction (axial direction) of the anvil roll 4 and the protrusion 4A is, as shown in FIGS. 8 (1) and (2), the elastic elastic member 12C in a state where a tensile force is applied in the longitudinal direction. It is preferable that the length is substantially the same as the outer diameter (width) of the cross section. In a paper diaper, it is common to fix a polyurethane thread rubber having a thickness of about 400 to 1000 dtex as an elastic stretch member to a sheet in a stretched state 2 to 3 times. The outer diameter of the cross section of the elastic elastic member 12C is approximately 0.18 to 0.22 mm, and the interval between the protrusions 4A, 4A,. More preferably, it is preferably 0.9 to 1 times (excluding 1) the outer diameter of the cross section of the elastic elastic member 12 </ b> C pulled in the longitudinal direction.

As shown in FIGS. 8A and 8B, the grooves between the protrusions 4A, 4A,... Are for accommodating the elastic elastic member 12C so that the elastic elastic member 12C is not narrowed by the protrusions. Therefore, the space | interval of an adjacent groove | channel corresponds with the arrangement | positioning space | interval of the elastic elastic members 12C, 12C, ... which adjoins in the continuous sheet 1. FIG. Further, the depth of the groove between the protrusions 4A, 4A,... May be deep enough to accommodate the elastic elastic member 12C and deep enough that the continuous sheet 1 does not sag excessively.
As shown in FIGS. 8 (1) and 8 (2), the protrusions 4A are arranged in a lattice pattern, and the distance between the protrusions 4A and 4A in the width direction of the anvil roll 4 is applied with a tensile force in the longitudinal direction. When the outer diameter of the elastic elastic member 12C is 1 to 1.1 times the outer diameter of the elastic elastic member 12C, when the protrusion 4A is guided between the anvil roll 4 and the horn 3, the elastic elastic member 12C is grooved. The inner layer 12 </ b> H and the outer layer 12 </ b> S of the continuous sheet 1 are narrowly pressed and are ultrasonically welded by the protrusion 4 </ b> A and the horn 3. As a matter of course, since the elastic elastic member 12 </ b> C is received in the groove, the tensioned elastic elastic member 12 </ b> C is not compressed by the protrusion 4 and the horn 3.

As shown in FIGS. 9 (1) and (2), this welding is performed in a state where tension is applied to the elastic elastic member 12C and in the vicinity of both ends in the width direction of the elastic elastic member 12C. When the load is removed (no tension), as shown in FIGS. 10 (1) and (2), the outer diameter of the cross section of the elastic elastic member 12C increases, and the elastic portion is elastic by the welded portion 11 between the inner layer 12H and the outer layer 12S. A pressing force is applied so as to sandwich the width direction of the elastic member 12C from both sides. As a result, the elastic elastic member 12C is fixed only by the frictional force with the inner and outer layers 12H and 12S without using an adhesive.
Thereby, deterioration by the adhesive of 12 C of elastic elastic members can be prevented. Moreover, since the elastic elastic member 12C is not bonded, the shearing S in which air permeability and softness are ensured can be formed. Moreover, since the raw material itself is melted and bonded, the fluctuation cost of hot melt can be reduced, and machine troubles caused by hot melt can be prevented.

  Further, as shown in FIGS. 11 (1) and 11 (2), the protrusions 4B of the anvil roll 4 are arranged in a lattice shape, and the interval between the protrusions 4B and 4B in the width direction of the anvil roll 4 is set in the longitudinal direction. In the case of 0.9 to 1 times (excluding 1) the cross-sectional outer diameter of the elastic elastic member 12C in a state where a tensile force is applied, both ends in the width direction of the elastic elastic member 12C are connected to the horn 3 and the protrusion. As shown in FIGS. 12A and 12B, the pressure is reduced by 4B, and ultrasonic welding is performed by the welding portion 11 together with the inner layer 12H and the outer layer 12S. In this case, as shown in FIGS. 13 (1) and (2), when the load is removed (no tension), in addition to the frictional force with the inner and outer layers 12H and 12S, both ends in the width direction of the elastic elastic member 12C The elastic elastic member 12C is fixed by the adhesive force of the part. Here, since the welding is performed only at the end portion of the elastic elastic member 12C, there is almost no risk of deterioration or cutting of the elastic elastic member 12C in a normal case.

  The arrangement of the protrusions is not limited to the lattice shape, but may be a staggered array of protrusions 4C as shown in FIG. At this time, the outer diameter of the cross section of the elastic expansion / contraction member 12C in a state where a tensile force is applied in the longitudinal direction between the protrusions 4C and 4C adjacent in the oblique direction with respect to the rotation direction of the anvil roll 4 in the width direction. 1 to 1.1 times, the elastic elastic member 12C is fixed only by the frictional force with the inner and outer layers 12H and 12S without using an adhesive. In addition, when the material which comprises the exterior sheet | seat 12 is the thing excellent in the frictional force, even if it is 1.1 times or more, it can fix. In addition, in the case of 0.9 to 1 times (excluding 1) the outer diameter of the cross section of the elastic elastic member 12C in a state where a tensile force is applied in the longitudinal direction, the frictional force with the inner and outer layers 12H and 12S. In addition to this, the elastic elastic member 12C is fixed by the adhesive force at both ends in the width direction of the elastic elastic member 12C.

In addition, if the space | interval (groove width) of protrusion 4A-4C and protrusion 4A-4C in the width direction exists in the said range with respect to the cross-section outer diameter of the elastic expansion-contraction member 12C in the state which applied tension | tensile_strength, anvil roll 22 The arrangement pattern of the protrusions 4A to 4C is not limited to a lattice shape or a staggered shape, and may be another pattern.
Further, when the elastic elastic member 12C is welded and fixed with the groove width being 0.9 to 1 times the outer diameter of the elastic elastic member 12C in an extended state (not including 1), the holding force of the elastic elastic member 12C is very high. Therefore, it is preferable, however, when the elongation rate is high, care should be taken because the elastic elastic member 12C can be easily cut. In particular, when the elongation rate is 300% or more, it is not preferable to make the groove width 0.9 to 1 time (not including 1).

  Further, when the elastic elastic member 12C is fixed only by frictional force without welding, when the elastic elastic member 12C and the inner and outer layers 12H and 12S have high frictional resistance, or when the elastic elastic member 12C has a low elongation rate, Although the groove width can be expanded to about 1.3 times the cross-sectional outer diameter of the elastic elastic member 12C in the expanded state, 1.0 to 1.2 times is preferable in the normal case, and 1.0 to 1.1 times is preferable. Particularly preferred. In this case, the holding force (friction resistance) becomes higher as the value becomes closer to 1 time, but there is also a risk of cutting the elastic elastic member 12C. Needless to say, the groove width needs to be in the above range and narrower than the diameter of the elastic elastic member 12C at the time of relaxation. In order to ensure the holding force, the groove width is desirably 70% or less of the relaxed diameter of the elastic elastic member 2.

  It is desirable that the depth of the groove (the height of the protrusions 4A to 4C) is also the same size as the groove width. Specifically, the depth of the groove is preferably 0.9 to 1.2 times the outer diameter of the cross section of the elastic elastic member 12C in the expanded state. The most preferable range is 1.0 to 1.1 times. If it is smaller than 1.0 times, the force for holding the elastic elastic member 12C becomes strong, but the entire elastic elastic member 12C may be welded. Further, it is not preferable that the depth of the groove is larger than the cross-sectional outer diameter of the elastic elastic member 12C at the time of relaxation. When the inner and outer layers 12H and 12S have the property of being easily distorted in the CD direction (anvil roll axial direction) like a nonwoven fabric, if the groove is too deep, the inner and outer layers 12H and 12S are stretched and distorted during pinching. Therefore, there is a possibility that sufficient force to sandwich the elastic elastic member 12C cannot be obtained.

  The shape of each of the protrusions 4A to 4C is circular in the illustrated example, but may be a polygon such as a triangle or a quadrangle, or a pattern such as an ellipse, a star, or a heart. If a shape without corners such as a circle or an ellipse is used, a soft texture can be obtained. If a shape with a corner is used and the corner is disposed so as to face the elastic elastic member 12C, the elastic elastic member 12C is retracted (the elastic elastic member 12C is contracted while being displaced without being fixed by the inner and outer layers 12H and 12S). Phenomenon) can be prevented more reliably. In this case, as the angle facing the elastic elastic member 12C is an acute angle, the pull-in is reduced. The angle of the angle facing the elastic elastic member 12C is preferably 15 to 120 degrees, and particularly preferably 30 to 90 degrees.

The size of the protrusions 4A to 4C is preferably 0.2 to 10 mm in diameter in the case of a circle, more preferably 0.3 to 5 mm, and particularly preferably 0.3 to 1 mm. Most preferably, it is 0.3 to 0.6 mm. The smaller the diameter, the better the texture of the sheet. However, if the diameter is too small, sufficient bonding strength between the inner and outer layers 12H and 12S cannot be obtained. Conversely, when the protrusions 4A to 4C are too large, the texture is lowered. For other shapes, the area in the case of a circle may be set as a reference, and the dimensional ratio between length and width may be extremely different. Area of the tip surface of the projection 4A~4C is preferably a 0.03~80mm ^2, more preferably from 0.07~20mm ^2, particularly preferably in the range of 0.07~0.8mm ^2, Most preferably, it is 0.07 to 0.3 mm ² .

  The spacing between the protrusions 4A to 4C in the MD direction (the circumferential direction of the anvil roll, the longitudinal direction of the elastic elastic member 12C) can generally be about 0.3 to 20 mm, but is not particularly limited to this. Alternatively, the protrusions 4A to 4C may be continuous in the form of a line (linear shape) in the MD direction. If the balance between the texture of the inner and outer layers 12H and 12S, the adhesive strength between the inner and outer layers 12H and 12S, and the fixing of the elastic elastic member 12C is balanced, for example, the protrusions 4A to 4C have a circular shape with a diameter of 0.3 to 0.6 mm. Then, the interval between the protrusions 4A to 4C may be, for example, about 0.3 to 1.0 mm in the MD direction and about 0.3 to 1.5 mm in the CD direction (axial direction of the anvil roll). Note that the spacing in the MD direction and the spacing in the CD direction of the protrusions 4A to 4C are indicated by reference numerals DMD and DCD, respectively, in FIG.

  When the arrangement of the protrusions 4A to 4C is the above-described lattice arrangement, since the protrusions 4A to 4C are located on both sides in the width direction at the same portion in the longitudinal direction of the elastic elastic member 12C, a high holding force can be obtained. However, the risk that the elastic elastic member 12C is welded or cut increases. On the other hand, when the staggered arrangement is used, the risk that the elastic elastic member 12C is welded or cut is lowered, but the holding power is also lowered. In the staggered arrangement, the rows of protrusions arranged in the MD direction at a predetermined periodic interval are provided with a predetermined interval in the CD direction, and the phase of the arrangement period of the protrusions in each row is shifted from the adjacent row. Yes, it may be arranged so that the phase is shifted by 1/2 with respect to the adjacent protrusion rows as shown in the example, but in order to make it closer to the lattice arrangement, for example, the phase is shifted by 1/4. May be. By adjusting the phase shift between 0 and 1/4, it is possible to balance the holding force of the elastic elastic member 12C and the avoidance of cutting.

  In order to obtain a soft texture, the area ratio of the welded portion 11 to the total area in the fixed region of the elastic elastic member 12C is preferably 40% or less, particularly preferably 30% or less, and 20% or less. Most preferably. In the non-fixed region of the elastic elastic member 12C, the area ratio of the welded portion 11 needs to be at least 2% in order to maintain the bonding strength of the inner and outer layers 12H and 12S. In the fixed region of the elastic elastic member 12C, the sheet bends due to the contraction of the elastic elastic member 12C. Therefore, a bonding strength higher than that of the non-fixed region of the elastic elastic member 12C is required. Therefore, in the fixed region of the elastic elastic member 12C, the area ratio of the welded portion 11 is preferably 5% or more, and more preferably 10% or more.

  On the other hand, by using the stretchable part forming method described above, as a first form of the disposable diaper, the elastic stretchable members 12C, 12C,... In the width direction of the elastic stretchable members 12C, 12C,. The elastic layers 12C, 12C,... Are fixed to the exterior sheet 12 by the frictional force with the exterior sheet 12 by welding the inner layer 12H and the outer layer 12S at predetermined intervals in the vicinity of both ends. The paper diaper which has a part can be manufactured.

  Moreover, as a 2nd form, in the state which applied tension | tensile_strength to elastic elastic member 12C, 12C, ..., the both ends of the width direction of elastic elastic member 12C, 12C, ..., the said inner layer 12H, and outer layer 12S, Are fixed to the exterior sheet 12 by the frictional force with the exterior sheet 12 and the adhesive force at the end in the width direction of the elastic stretch member 12C. The paper diaper which has the expansion-contraction part of this can be manufactured.

  In the case where the elastic stretchable member is provided over a wide range as in the case of the waistline portion of this embodiment, as shown in FIG. 15, the portion fixed by the welded portion 11 is intermittently arranged in the longitudinal direction (MD direction) of the elastic stretchable member 12C. Provided (that is, a welded portion group region 44 composed of a large number of welded portions 11 formed at the above-described arrangement / interval and a non-welded portion region 45 having no welded portion are provided in the longitudinal direction (MD direction) of the elastic elastic member 12C. Since the stretchability is improved and the area of the welded portion 11 is reduced, a softer texture and higher air permeability can be obtained. Of course, as shown in FIG. 16, the welded portion group region 44 fixed by the welded portion 3 can be continuously provided over the entire longitudinal direction (MD direction) of the elastic elastic member 2.

  Such an intermittent arrangement can also be applied to a case where a large number of elastic elastic members 2 are arranged side by side. However, if the longitudinal direction (MD direction) position of the fixing portion by the welded portion of each elastic elastic member 2 is different, the elastic elastic members 2 The wrinkles formed by the shrinkage become irregular, and an uneven surface with poor appearance is formed. Therefore, when adopting the intermittent arrangement as described above, as shown in FIG. 15, it is preferable to align the position of the fixing portion by the welded portion in the longitudinal direction (MD direction) of the elastic elastic member 2. Specifically, an elongated welded portion group region 44 that vertically cuts the elastic elastic members 12C arranged side by side and a non-welded portion region 45 that cuts the elastic elastic members 12C arranged side by side are arranged in the longitudinal direction of the elastic elastic members 12C. They are formed alternately in the direction (MD direction). As a result, a beautiful shirring of the kites is formed. The width (the distance between the centers of the welded portions 11 located at both ends) W44 of the welded portion group region 44 is preferably about 2 to 10 mm, and more preferably about 3 to 5 mm. It is preferable that the center interval DCT between adjacent welded portion group regions 44 is about 5 to 20 mm. Furthermore, it is more preferable that the relationship of DCT / 2 ≧ W44 is satisfied.

  Moreover, in the paper diaper of this invention, as above-mentioned, the inner layer 12H and the outer layer 12S in an expansion-contraction part are good also as a structure bonded together by ultrasonic welding or heat welding, without using an adhesive agent at all. In addition, as described above, the elastic elastic member 12C on the back side and / or the elastic elastic member 12C on the abdominal side may be cut or not provided at the portion of the exterior sheet 12 that overlaps the absorbing portion 20. Further, when the elastic expansion / contraction member 12C has a high expansion ratio and a large tensile force is applied to the expansion / contraction part during use, the elastic expansion / contraction member 12C can be sufficiently fixed only by the frictional force with the inner and outer layers 12H and 12S. There is a risk that it cannot be maintained. In that case, at least one end of the elastic expansion / contraction member 12C in the longitudinal direction is elastically expanded / contracted by the substantially linear welding wires 12D and 12D arranged to cut the elastic expansion / contraction member 12C disposed in parallel. The member 12C and the inner layer 12H and the outer layer 12S of the exterior sheet 12 may be welded and fixed to secure the elastic elastic member 12C.

  On the other hand, as can be seen from the above embodiment, the ultrasonic bonding method is suitable for carrying out the stretchable part forming method of the present invention, but it is composed of an embossed roll provided with unevenness and a plain roll facing the heat, and heat and It can also be carried out using a hot embossing adhesion method in which a sheet is pressure-bonded by pressure.

<Evaluation test>
By the manufacturing method according to the present invention using ultrasonic welding, various stretchable sheets are manufactured under the conditions shown in Table 1, and “softness”, “sheet interlayer adhesion”, “difficult to pull out (retraction is difficult to occur) ”And“ difficult to cut ”were evaluated.
In addition, as an inner sheet and an outer sheet, a spunbond nonwoven fabric (one layer, basis weight: 20 g / m ² , thickness: 0.18 mm, fineness 2.2 dtex, composition: PE (sheath) / PP (core) = 1 / 1, sheet width: 150 mm). Further, as the elastic stretchable member 2, a spandex of 470 dtex (diameter: 0.311 mm) is used, and is stretched to 270% along the lateral direction of the sheet (2.7 times the original length, the diameter is 0.162 mm). Fixed in the state. Further, 20 elastic stretch members 2 were arranged in parallel at intervals of 5 mm.
“Softness” is a sensory evaluation in comparison with a sheet in which an elastic elastic member is fixed with a conventional adhesive, and 9 to 10 test subjects are evaluated as soft. Was evaluated as ◯, 4 to 6 were evaluated as soft, △ was evaluated as 3 or less were evaluated as ×. In the evaluation of “sheet interlayer adhesion”, “◎” indicates that the sheet itself was destroyed when the adhered sheet was peeled off by hand, and “◯” indicates that the sheet was partially broken or accompanied by delamination. In addition, a sample which was peeled off while leaving a slight fluff was represented by Δ, and a sample which did not substantially adhere was represented by ×. “In the evaluation of the difficulty of pulling out (the difficulty of pulling in), when the sheet is cut, the elastic elastic member from the cut part is 1 mm or less, ◎◎, 3 mm or less is ◎, 5 mm The following were marked with ◯, those with 10 mm or less as Δ, and those with 11 mm or more as x: In the evaluation of “difficult to cut”, there was one cut in the range of 100 mm in the length direction of the sheet. The following were evaluated as ◎, those at 5 or less locations as ◯, those at 10 locations or less as Δ, those at 20 locations or less as Δ to ×, and those at 21 locations or more as ×.

It is a perspective view of a pants-type diaper. It is a body side top view of a diaper of a deployment state. FIG. 3 is a cross-sectional view taken along line III-III in FIG. 2. It is an outer surface side top view of a diaper of a deployment state. It is the VV arrow directional cross-sectional schematic diagram of FIG. It is an enlarged view of a shearing part. It is a schematic diagram for demonstrating an expansion-contraction part formation apparatus. It is the width direction sectional view of 1st Embodiment which shows the state where the continuous sheet was pinched | interposed into the horn and the anvil roll, and its cross-sectional view. It is the cross-sectional view of the width direction of 1st Embodiment of the continuous sheet of the state which applied the tensile force to the elastic elastic member, and its cross-sectional view. It is the cross-sectional view of the width direction of 1st Embodiment of the continuous sheet of the state which does not apply tensile force to an elastic elastic member, and its cross-sectional view. It is the width direction sectional drawing of 2nd Embodiment which shows the state by which the continuous sheet was pinched | interposed into the horn and the anvil roll, and its cross section. It is the cross-sectional view of the width direction of 2nd Embodiment of the continuous sheet of the state which applied the tensile force to the elastic elastic member, and its cross-sectional view. It is the cross-sectional view of the width direction of 2nd Embodiment of the continuous sheet of the state which does not apply tensile force to an elastic elastic member, and its cross-sectional view. It is a cross-sectional view showing a state in which a continuous sheet is sandwiched between anvil rolls having an array of staggered protrusions. It is the schematic which shows the example of application to the trunk part part shirring of a pants-type paper diaper. It is the schematic which shows the other application example to the trunk periphery part shearing of a pants-type paper diaper.

DESCRIPTION OF SYMBOLS 1 ... Continuous sheet, 2 ... Ultrasonic vibration source, 3 ... Horn, 4 ... Anvil roll, 4A, 4B, 4C ... Projection, 10 ... Underpants type disposable diaper, 11 ... Welding part, 12 ... Exterior sheet, 12A ... Joining area 12E ... Leg circumference edge, 12S ... Outer layer, 12H ... Inner layer, 12C ... Elastic elastic member, 12D ... Welding wire, 12P ... Permeability improving part, 13 ... Display part, 20 ... Absorbing part, 30 ... Top sheet, 40 ... Intermediate sheet (second sheet), 50 ... Absorbing element, 56 ... Absorber, 58 ... Cover sheet, 60 ... Barrier cuff, 64 ... Barrier sheet, 70 ... Body fluid impermeable sheet (back sheet), 72 ... First 2 body fluid impermeable sheet, 80 ... holding sheet, S ... shirring.

Claims (6)

An exterior sheet having an inner layer and an outer layer, and an absorption part that is provided on the body side of the exterior sheet and absorbs and holds an object,
A paper diaper having a stretchable part in which a plurality of elastic stretchable members arranged in parallel are sandwiched between the inner layer and the outer layer in the waistline part,
With the tensile force applied to the elastic elastic member , the inner layer and the outer layer are intermittently welded in the supply direction in the vicinity of both sides in the diameter direction of the elastic elastic member,
Thereafter, in the cross-sectional space closed by the welded portion between the inner layer and the outer layer, the elastic elastic member is released with a tensile force to increase the cross-sectional outer diameter of the elastic elastic member. The elastic part was formed by fixing the elastic elastic member to the sheet by the frictional force between the outer surface and the layer sheet forming the closed space,
Paper diapers characterized by that. An exterior sheet having an inner layer and an outer layer, and an absorption part that is provided on the body side of the exterior sheet and absorbs and holds an object,
A paper diaper having a stretchable part in which a plurality of elastic stretchable members arranged in parallel are sandwiched between the inner layer and the outer layer in the waistline part,
Wherein while applying a tensile force to the resilient and elastic members, the side portions overlapping the sides and near the resilient and elastic members in the diametrical direction of the resilient and elastic members, and said inner and outer layers intermittently to the feed direction Welded,
Thereafter, in the cross-sectional space closed by the welded portion between the inner layer and the outer layer, the elastic elastic member is released with a tensile force to increase the cross-sectional outer diameter of the elastic elastic member. The elastic part was formed by fixing the elastic elastic member to the sheet by the frictional force between the outer surface and the layer sheet forming the closed space, and the joining force with the sheet at the side part,
Paper diapers characterized by that.   The disposable diaper according to claim 1, wherein the elastic elastic member is configured in a net shape by a plurality of elastic yarns arranged in parallel and a plurality of elastic yarns orthogonal to the elastic yarns. The paper diaper according to any one of claims 1 to 3, wherein the welding is configured by ultrasonic welding or heat welding . The paper diaper according to any one of claims 1 to 4, wherein the elastic stretchable member is cut or not provided at a portion of the exterior sheet that overlaps the absorbing portion. The elastic elastic member and the inner layer and the outer layer of the exterior sheet are welded and fixed to each other at at least one end in the longitudinal direction of the elastic elastic member by a welding line that vertically cuts the elastic elastic member. The paper diaper according to any one of 5.

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