WO2008041639A1

WO2008041639A1 - Paper diaper, method of forming stretchable section of absorbent article, and device for forming the stretchable section

Info

Publication number: WO2008041639A1
Application number: PCT/JP2007/069010
Authority: WO
Inventors: Hiroyuki Yano; Sadanao Manabe
Original assignee: Daio Paper Corporation
Priority date: 2006-09-29
Filing date: 2007-09-28
Publication date: 2008-04-10

Abstract

[PROBLEMS] A technique for improving stretchability etc. of a stretchable section of an absorbent article such as a paper diaper. With the technique, an elastic stretchable member and an exterior sheet are fixed together without the use of an adhesive agent. [MEANS FOR SOLVING PROBLEMS] In the stretchable section, an inner layer (12H) and an outer layer (12S) are fusion-bonded together at predetermined intervals near both ends in the lateral direction of the elastic stretchable member (12C) with tensile force applied to the elastic stretchable member (12C). By this, the elastic stretchable member (12C) is fixed to the exterior sheet (12) by friction force between the stretchable member (12C) and the exterior sheet (12).

Description

Specification

TECHNICAL FIELD OF THE INVENTION Technical Field

TECHNICAL FIELD [0001] 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 disposed on a waist part. The present invention also relates to a method for forming a stretchable part and an apparatus for forming the same in an absorbent article.

Background art

[0002] For example, in a pants-type disposable diaper that is an absorbent article, as shown in Figs. 1 and 6, there is a case where shirring s is formed around the abdomen and waist as an expansion / contraction part to add a fitting function (for example, And Patent Document 1). This shearing S is made by sandwiching elastic elastic members 2, 2,... Such as rubber thread with an exterior sheet 1 formed by laminating and fixing two or three air permeable water-repellent nonwoven fabrics. The elastic elastic members 2, 2, ... and the exterior sheet 1 are intermittently fixed with an adhesive such as hot melt while the elastic elastic members 2, 2, ... are contracted. Is. In FIG. 1, WO indicates a waste opening, and LO indicates a redder 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,. Generally, an adhesive such as hot melt is applied to both 2, 2,... And the exterior sheet 1, and then fixed by niping with elastic elastic members 2, 2,.

[0004] Further, in recent years, an ambinole roll (not shown) that is intermittently arranged and is constituted by a projection that serves as an adhesive surface, and a heat-sealing device (not shown) that is arranged at a position facing the ambinore roll. In this technology, the sheet 1 is continuously supplied with the elastic elastic members 2, 2,... Sandwiched between them, and the exterior sheet 1 and the elastic elastic members 2, 2,. It has been introduced.

Patent Document 1: JP 2002-172132 A

Patent Document 2: JP 2004-330777 A Disclosure of the invention

Problems to be solved by the invention

[0005] However, in the case of using a hot melt adhesive, in order to maintain the adhesive strength of the adhesive constant, the manufacturing equipment such as the temperature management of the adhesive is complicated, and an elastic elastic member such as rubber is used. Causes of machine troubles such as increasing the resistance of sliding parts of manufacturing equipment and contamination of products with foreign substances because the adhesive force and the adhesive applied are applied to manufacturing equipment such as pressure rolls and transfer belts. There was a risk of becoming. In addition, the heat for dissolving the hot melt (150 to 200 ° C.) has a detrimental effect that the machine parts deteriorate and the ambient temperature rises.

[0006] On the other hand, an adhesive other than hot melt is not preferable because a volatile solvent is harmful to the human body or has fluidity at room temperature and cannot exert sufficient adhesive strength. Moreover, when a stretchable part is formed by fixing an elastic stretchable member and a nonwoven fabric (exterior sheet) with an adhesive as a product of a paper diaper, there is a problem that the breathability and softness of the stretchable part are lost. Furthermore, the method of fixing in the pinched state of the invention described in Patent Document 2 has a problem that the elastic elastic member such as rubber is deteriorated and the strength and elasticity of the elastic elastic member are lowered.

[0007] Thus, if there is the above-mentioned problem in the stretchable part forming method, there is room for improvement in the breathability, softness, stretchability, etc., even in the stretchable part of the conventional pants-type paper diaper that stretches. There is.

[0008] Therefore, the main problem of the present invention is to improve the breathability, softness, stretchability, etc. by fixing the elastic stretchable member and the exterior sheet to the stretchable part without using any adhesive! The purpose is to provide disposable diapers. Another object is to provide a stretchable portion forming method and equipment for fixing an elastic stretchable member and a sheet without using an adhesive.

Means for solving the problem

The present invention that has solved the above problems is as follows.

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 the object,

[0010] A plurality of elastic stretchable parts arranged in parallel between the inner layer and the outer layer in the waist part A paper diaper having an elastic part sandwiched between materials,

[0011] The stretchable portion is formed by welding the inner layer and the outer layer at a predetermined interval in the vicinity of both end portions in the width direction of the elastic stretchable member in a state where a tensile force is applied to the elastic stretchable member. The elastic member is configured to be fixed to the exterior sheet by frictional force with the exterior sheet.

[0012] A paper diaper characterized by the above.

[0014] 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,

[0015] The stretchable portion is formed by welding both ends of the elastic stretchable member in the width direction and the inner layer and the outer layer at a predetermined interval in a state where a tensile force is applied to the elastic stretchable member. The elastic stretchable member is configured to be fixed to the exterior sheet by the frictional force with the exterior sheet and the adhesive force at the end in the width direction of the elastic stretchable member.

[0016] A paper diaper characterized by the above.

The disposable diaper according to claim 1 or 2, wherein the elastic elastic member is formed in a net shape by a plurality of elastic yarns arranged in parallel and a plurality of elastic yarns orthogonal to the elastic yarns.

[0018] (Function and effect)

The stretchable portion is elastic when the tensile force is applied to the elastic stretchable member (stretched state) and the inner layer and the outer layer are welded at a predetermined interval in the vicinity of both ends in the width direction of the elastic stretchable member. By adopting a configuration in which the elastic member is fixed by the frictional force with the exterior sheet, deterioration due to the adhesive can be prevented. In addition, since the elastic stretchable member is not bonded, a stretchable portion that ensures air permeability and softness can be formed. The welding can be ultrasonic welding or heat welding. However, it is more preferable to use ultrasonic welding because the elastic expansion member is less affected by heat and pressure than the thermal welding on the periphery of the exterior sheet.

[0019] Further, in the state in which the elastic part is stretched with the tensile force applied to the elastic elastic member, the width direction of the elastic elastic member By welding the both end portions and the inner layer and the outer layer at a predetermined interval, the elastic stretchable member is attached to the exterior by the frictional force with the exterior sheet and the adhesive force at the end in the width direction of the elastic stretchable member. By adopting a configuration in which the elastic stretchable member is fixed to the sheet, the elastic stretchable member is more firmly fixed by the adhesive force at the end in the width direction of the elastic stretchable member in addition to the frictional force with the exterior sheet. Note that the adhesive is only bonded to the end in the width direction of the elastic elastic member, so there is no risk of deterioration or cutting of the elastic elastic member.

[0020] Note that the mechanism in which the elastic elastic member is fixed by the frictional force with the exterior sheet is such that a tensile force is applied to the elastic elastic member, and the inner layer and the outer side in the vicinity of both ends in the width direction of the elastic elastic member. By intermittently welding the layers and fixing the elastic elastic member to the exterior sheet, if the load is subsequently removed (no tension), the outer diameter of the cross section of the elastic elastic member increases, and the inner layer and the outer layer Due to the welded portion, the pressing force is applied so as to sandwich the width direction of the elastic elastic member from both sides. As a result, the elastic elastic member is fixed only by the frictional force with the sheet without fixing the elastic elastic member with the adhesive.

[0021] As the elastic elastic member, a member configured in a net shape by a plurality of elastic yarns arranged in parallel and a plurality of elastic yarns orthogonal to these may be used.

The paper diaper according to any one of claims 1 to 3, wherein the inner layer and the outer layer in the stretchable part are bonded by ultrasonic welding or heat welding without using an adhesive. .

The back elastic elastic member and / or the abdominal elastic elastic member is cut at a portion of the exterior sheet that overlaps the absorbing portion, or is provided, or is provided. The disposable diaper of any one of thru | or 4.

A configuration in which at least one end portion in the longitudinal direction of the elastic elastic member is welded and fixed to the elastic elastic member and the inner layer and the outer layer of the exterior sheet by a welding line that vertically cuts the elastic elastic member arranged in parallel. The paper diaper according to claim 1, wherein the force is any one of claims 1 to 5. [0025] (Function and effect)

By adopting a configuration in which the inner layer and the outer layer in the stretchable part are bonded by ultrasonic welding or heat welding without using an adhesive, the breathability and softness of the stretchable part are further improved.

[0026] In addition, the back elastic stretch member and / or the abdomen elastic stretch member is cut at the portion of the exterior sheet that overlaps the absorbent portion, or the force that is provided or is provided. By doing so, the contraction force acting on the absorption part is weakened or eliminated, and absorption inhibition due to contraction of the absorption part is less likely to occur.

[0027] Further, at least one end of the elastic elastic member in the longitudinal direction is welded and fixed between the elastic elastic member and the inner layer and the outer layer of the exterior sheet by a welding line that vertically cuts the elastic elastic member arranged in parallel. By adopting such a configuration, the elastic stretchable member can be more securely fixed at both ends in the longitudinal direction.

[0028] <Invention of Claim 7>

Using a continuous sheet with a plurality of elastic elastic members arranged in parallel between the inner sheet and the outer sheet,

[0029] A method for forming a stretchable part of an absorbent article, wherein the elastic stretchable member is fixed by intermittently bonding the inner sheet and the outer sheet in a supply direction,

[0030] With the tensile force applied to the elastic elastic member, the inner sheet and the outer sheet are intermittently welded in the vicinity of both ends in the width direction of the elastic elastic member, and the elastic elastic member is fixed to the sheet.

[0031] A method for forming a stretchable part, characterized in that.

[0033] A method for forming a stretchable part of an absorbent article, wherein the elastic stretchable member is fixed by intermittently bonding the inner sheet and the outer sheet in a supply direction,

[0034] With the tensile force applied to the elastic elastic member, both ends of the elastic elastic member in the width direction are intermittently welded to the inner sheet and the outer sheet to fix the elastic elastic member to the sheet. [0035] A method for forming the stretchable portion, characterized by the above.

[0036] (Function and effect)

With the tensile force applied to the elastic elastic member, the inner sheet and the outer sheet are intermittently welded in the vicinity of both ends in the width direction of the elastic elastic member, and the elastic elastic member is fixed to the sheet. When the load is removed (no tension), the cross-sectional outer diameter of the elastic expansion / contraction member increases, and a pressing force is applied so that the width direction of the elastic expansion / contraction member is sandwiched from both sides by the welded portion between the inner sheet and the outer sheet. . As a result, since the elastic elastic member is fixed only by the frictional force with the sheet without fixing the elastic elastic member with the adhesive, the force S can be prevented from being deteriorated by the adhesive. In addition, since the elastic elastic member is not bonded, it is possible to form an expansion / contraction part in which air permeability and softness are ensured. The welding can be ultrasonic welding or heat welding. However, it is more preferable to use ultrasonic welding because the elastic stretch member has less influence of heat and pressure on the periphery of the sheet than ultrasonic welding.

[0037] Further, with the tensile force applied to the elastic elastic member, the both ends of the elastic elastic member in the width direction are intermittently welded to the inner sheet and the outer sheet to fix the elastic elastic member. Thus, in addition to the frictional force with the sheet, the elastic expansion / contraction member is more firmly fixed by the adhesive force at the end in the width direction of the elastic expansion / contraction member. Note that there is no risk of deterioration or cutting of the elastic expansion / contraction member because the bonding is only at the end in the width direction of the elastic expansion / contraction member.

[0039] Expansion / contraction of the absorbent article, wherein the elastic expansion / contraction member is fixed by intermittently adhering the inner sheet and the outer sheet to the supply direction in a state where a tensile force is applied to the elastic expansion / contraction member. A part forming device,

[0040] The apparatus includes an ultrasonic vibration source, a horn connected to the ultrasonic vibration source, and an anvil roll disposed to face the horn.

[0041] On the outer peripheral surface of the anvil roll, a plurality of protrusions serving as adhesive surfaces are formed, [0042] These protrusions are in a lattice shape and are configured to have substantially the same length as the cross-sectional outer diameter of the elastic elastic member in a state in which the space force between the protrusions in the width direction of the anvil roll and the tension is applied.

[0043] A stretchable part forming apparatus characterized by the above.

[0045] Expansion / contraction of the absorbent article, wherein the elastic expansion / contraction member is fixed by intermittently bonding the inner sheet and the outer sheet to the supply direction in a state where a tensile force is applied to the elastic expansion / contraction member. A part forming device,

[0046] The apparatus includes an ultrasonic vibration source, a horn connected to the ultrasonic vibration source, and an anvil roll disposed to face the horn.

[0047] On the outer peripheral surface of the anvil roll, a plurality of protrusions serving as adhesive surfaces are formed,

[0048] These protrusions are staggered, and the distance in the width direction between the protrusions adjacent to each other in the oblique direction with respect to the rotation direction of the anvil roll is equal to the outer diameter of the cross section of the elastic elastic member in a state where a tensile force is applied. Composed of approximately the same length,

[0049] A stretchable part forming apparatus characterized by the above.

[0050] (Function and effect)

On the outer peripheral surface of the anvil roll, there are formed a plurality of protrusions that become adhesive surfaces, and these protrusions are in a lattice shape, and the spacing between the protrusions in the width direction of the anvil roll and the elastic elastic member in a state where a tensile force is applied The outer and outer sheets of the continuous sheet are narrow in a state where the entire elastic elastic member or the main part is stored in the groove between the protrusions of the anvil roll. It is pressed and ultrasonically welded by the projection and horn. As a result, when the entire elastic expansion / contraction member is in the groove, the elastic expansion / contraction member is fixed only by the frictional force with the sheet without using an adhesive. When the main part of the member is housed in the groove and both ends in the width direction are constricted by the horn and the protrusion, the end of the elastic expansion / contraction member in the width direction in addition to the frictional force with the sheet The elastic stretchable member is fixed by the adhesive force.

[0051] On the outer peripheral surface of the anvil roll, a plurality of protrusions serving as adhesive surfaces are formed. The staggered projections that are adjacent to each other in the diagonal direction with respect to the rotation direction of the anvil roll have a width in the width direction that is approximately the same as the cross-sectional outer diameter of the elastic elastic member in the state in which a tensile force is applied. However, the same effect as described above can be obtained.

The invention's effect

[0052] The paper diaper of the present invention has the advantage that 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, etc. can be improved. Brought about. In the stretchable part forming method and the forming apparatus of the present invention, there are advantages that the stretchable part can fix the elastic stretchable member and the sheet without using an adhesive.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the disposable diaper of the present invention will be described based on an example of a pants-type use V shown in the accompanying drawings, a disposable diaper! V, a loose tape-type use! /, A disposable diaper It can also be applied to other forms of disposable diapers.

The pants-type disposable diaper 10 shown in FIGS. 1 to 5 includes an exterior sheet 12 that constitutes an exterior part, and an absorbent part 20 that is 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 used for supporting the absorption part 20 to the wearer. Part

[0055] (Exterior sheet)

The exterior sheet 12 has 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. Each side edge of the intermediate portion L is formed as a leg circumference edge 12E that is constricted along the circumference of the wearer's leg, and this is a portion into which the wearer's leg is placed. As a result, the exterior sheet 12 has a substantially hourglass shape as a whole. The absorbing portion 20 has a force to take an arbitrary shape, a force that can be applied, and a rectangular shape in the illustrated form. The intermediate portion L of the exterior sheet 12 may be composed of only the front end side portion W and the rear end side portion W which are not essential. [0056] As shown in FIG. 2, the exterior sheet 12 has the absorbent portion 20 installed and fixed at a predetermined position, and the front and rear end portions thereof are folded and fixed onto the front end portion and the rear end portion of the absorbent portion 20. Folded back and forth so that the ventral side 12 F and the dorsal side 12B overlap, and the joint areas 12A on the both sides of the ventral side 12F and the dorsal side 12B of the exterior sheet 12 are heat-sealed with hook material, buttons, fasteners, etc. Joined. As a result, the pant-type use / removal diaper having the waist opening WO and the pair of redder openings LO having the structure shown in FIG.

[0057] In the illustrated example, the force S in which the width of the intermediate portion of the absorber 20 in the front-rear direction (longitudinal direction, ie, the vertical direction in FIG. 2) is longer than the width connecting the peripheral edges of the outer sheet 12 is shown. The relationship may be reversed or the same width.

As shown in FIG. 5, the exterior sheet 12 is elastic between the breathable outer layer 12S and the breathable inner layer 12H in the front end side portion W and the rear end side portion W of the waistline portion. The stretching members 12C, 12C,... Are sandwiched in the stretched state, and in this state, both layers 12S, 12H are fixed by ultrasonic welding or heat welding. As a result, the shearing S as the stretchable part is formed in the waist part. Although details of the structure of the stretchable portion and the method of forming the stretchable portion will be described later, the elastic stretchable member 12C is a force that is fixed to the exterior sheet 12 only by the frictional force with the exterior sheet 12, or the frictional force and the elastic stretchable member. It is fixed to the exterior sheet 12 by both the adhesive force at the end in the width direction of 12C. 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 to fix in this portion also by ultrasonic welding or heat welding! /.

[0059] 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, more preferably 10% or less. preferable. Also, in order to maintain the bonding strength between the outer layer 12S and the inner layer 12H, the area ratio of the welded portion is preferably 2% or more.

[0060] As the outer layer 12S and the inner layer 12H of the exterior sheet 12, it is preferable to use a water-repellent non-woven fabric from the viewpoint of touch and waterproofness as long as it is a breathable material without particular limitation. Each of the outer layer 12S and the inner layer 12H may be formed by laminating a plurality of materials. As the nonwoven fabric, for example, a polypropylene resin (PP), a polyethylene resin (PE), a polyethylene terephthalate resin (PET), or a composite of these can be used. The Further, a film made of polyethylene resin or the like may be sandwiched between the layers of the nonwoven fabric. Each thickness of the outer layer 12S and the inner layer 12H is preferably a force S that can be determined as appropriate, and the thickness of the outer layer 12S is preferably equal to or greater than the thickness of the inner layer 12H. It is preferable that the outer layer 12S and the inner layer 12H each have a basis weight in the range of 5 to 30 g / m ² . Further, 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.

[0061] (Elastic elastic member)

As the elastic elastic member 12C, a known elastic yarn can be used as long as it has elastic properties 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 rubbers and elastomers based on mixtures of these with other polymers such as polystyrene or polyolefins can be used. Elastic yarns from segmented polyester or polyether urethane urea can also be used.

[0062] The thickness of the elastic elastic member 12C can be arbitrarily set. The cross-sectional shape is not limited to a circle, but can be freely selected from an ellipse, a rectangle, and other geometric shapes.

[0063] Further, the elastic elastic member 12C is not limited to a thread-like member, and although not shown, a wide ribbon-like member may be used. In the case of a ribbon, it is preferable that both end portions 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 in the vicinity of both ends in the width direction even for the elastic yarn orthogonal to the tension direction elastic yarn alone! In this case, the orthogonal elastic yarn and the welded portion may be separated. 1S If the welded portion is welded not only to both ends in the width direction of the elastic yarn but also to the center, the elastic yarn may break or the welded portion may become hard. This is not preferable.

[0064] If the elastic expansion / contraction member 12C force is provided over the entire waist region W, the elastic expansion / contraction member 12C itself hits the lower waist region even if the contraction force of the elastic expansion / contraction member 12C itself is weak, so that the product is suitable for the wearer. To fit.

[0065] As shown in the figure, in the portion overlapping with the absorber 56 described later, the dorsal side and the stomach It is also a preferable form to cut the side elastic elastic members 12C, 12C,. Instead, it is also possible to adopt a form in which the back and ventral elastic elastic members 12C, 12C,... As for this cutting method, as disclosed in Japanese Patent 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. In this way, if 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 absorption inhibition due to the contraction of the absorber 56 is performed. Is less likely to occur. In addition, only one of the dorsal and ventral elastic elastic members 12C, the elastic elastic member 12C is discontinuous, only a part of the dorsal or ventral elastic elastic member 12C is discontinuous, or a combination thereof Appropriate changes can be made, such as discontinuity of only a part of the elastic stretch member 12C on either the back side or the ventral side.

[0066] Also, in this way, when the elastic stretchable member 12C is made discontinuous at the portion overlapping the absorber 56, the narrower stretchable portion prevents the slippage at the time of wearing, so a high stretch rate is achieved. It is preferable to fix the elastic elastic member 12C. Specifically, the elastic stretch member 12 C preferably has an elongation rate of 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 the absorber 56, it is preferable that the stretch rate of the elastic stretchable member 12C is about 150 to 250%. It is not preferable because it becomes too much and the wearer feels uncomfortable.

[0067] Further, when the elastic elastic member 12C is fixed at a high extension 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 strongly contracted, so that the elastic elastic member 12C There is a possibility that pull-in (a phenomenon in which the elastic elastic member 2 contracts while shifting without being fixed by the sheets 1A and 1B) at the end of the discontinuous portion side may occur. Such pull-in progresses gradually with long-term wearing, and the tightening around the waist loosens, causing the diaper to slip off. In the past, a large amount of adhesive was used to prevent this phenomenon, and the texture was likely to deteriorate. In particular, at an elongation rate of 300% or more, it was difficult even to manufacture while suppressing pulling. On the other hand, in the present invention, even when the elastic stretch member 12C has a high elongation rate, particularly at an elongation rate of 300% or more, the elastic stretch member 12C hardly occurs and the amount of adhesive used is small. By drastically reducing, it becomes excellent in texture and breathability. If the friction resistance of the outer layer 12S and the inner layer 12H is low and the elongation rate of the elastic elastic member 12C is high, a force that may cause retraction even with the fixing structure disclosed in the present application. By using a small amount of adhesive in combination, it is possible to prevent pull-in with almost no loss of texture and air permeability.

[0068] (Transparency improvement part)

Although not shown, the outer layer 12S has almost all the force S except the front and rear edges of the front and rear direction intermediate portion L in the outer sheet 12 except for the portion where the elastic elastic member 12C is disposed. It is good also as the permeability improvement part 12P which does not have the inner layer 12H and the elastic elastic member 12C. In this case, the inner layer 12H does not overlap the force inner layers 12H and 12H that are individually provided on the front end side portion W and the rear end side portion W of the exterior sheet 12, respectively. As a result, the air permeability in the crotch portion and the portion near the crotch where it is easily sultry is drastically improved, and sultry can be prevented. Further, 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 and strength are improved. In addition, in this embodiment, the elastic elastic member 12C is provided over the entire waist region W, so that it is possible to prevent stuffiness without deteriorating the fit. Further, 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, it is preferable to cover the body fluid impervious sheet 70 of the absorbent part 20 with a cloth-like material such as a nonwoven fabric at the intermediate part. In this way, it can be freely selected without considering the characteristics related to welding and friction with the elastic expansion / contraction material 12C.For example, it is suitable for texture, softness, breathability and resistance, and other physical properties. Can be made into material

[0069] The length of the permeability improving portion 12P in the front-rear direction is preferably 30% or more, particularly 35-65% or more of the front-rear direction length 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 upper permeability 12P, the better. Will lose the fit.

[0070] (Absorber)

As shown in FIG. 3, as the absorbent portion 20, it is possible to use a member provided with a top sheet 30 made of a nonwoven fabric or the like and an absorbent element 50, for example, through which body fluid passes, in order from the use surface side. In a normal case, a body fluid impermeable sheet (also called a back sheet) 70 force S 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. 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 the 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, it is possible to provide barrier force hose 60, 60 standing on both sides of the absorption part 20.

[0071] (Top sheet)

The top sheet 30 has a property of permeating body fluid. Therefore, 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, it is possible to use polypropylene resin (PP), polyethylene resin (PE), polyethylene terephthalate resin (PET), or a combination of these as described above. Furthermore, the nonwoven fabric may be manufactured by any processing. Examples of the processing method include known methods such as the spunlace method, the spunbond method, the thermal bond method, the melt blown method, and the needle punch method. For example, if you want flexibility and drapeability, the spunbond method and spunlace method are bulky and soft, and if you want bulkiness and softness, it is an air-through method, point bond method, thermal bond strength S, and a preferred processing method. .

[0072] The top sheet 30 may be composed of a single sheet or a laminated sheet obtained by laminating two or more sheets. Similarly, the top sheet 30 may be composed of one sheet or two or more sheets in the plane direction.

[0073] (Intermediate sheet) In order to quickly transfer the body fluid that has passed through the top sheet 30 to the absorbent body, it is possible to install an intermediate sheet 40 that is faster than the top sheet 30 and that is normally referred to as a “second sheet”. This intermediate sheet 40 prevents the “reversal” phenomenon of the absorbed body fluid from the absorbent body by moving the body fluid quickly to the absorbent body to enhance the absorption performance by the absorbent body, It can always be in a dry state. The intermediate sheet 40 can be omitted.

[0074] Examples of the intermediate sheet 40 include the same material as the top sheet 30, spun lace, pulp nonwoven fabric, 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.

[0075] The intermediate sheet 40 in the form shown in the figure is disposed in the center shorter than the width of the absorber 56, but may be provided over the entire width. The length in the longitudinal direction of the intermediate sheet 40 may be the same as the length of the absorbent body 56, or may be within a short length range centered on the region for receiving body fluid. A typical material for the intermediate sheet 40 is a non-woven fabric having excellent body fluid permeability.

[0076] (Body fluid impermeable sheet)

The body fluid impermeable sheet 70 is simply a sheet disposed on the back side of the absorber 56, and in the present embodiment, it 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, or a nonwoven fabric that is substantially impervious to liquids by interposing a waterproof film (in this case, A body fluid-impermeable sheet is composed of a waterproof film and a non-woven fabric.). Of course, in addition to this, it is also possible to exemplify liquid-impervious and moisture-permeable materials that have been favored and used in recent years from the viewpoint of preventing stuffiness. 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 manner can be given.

[0077] The body fluid impermeable sheet 70 has a force capable of preventing side leakage of body fluid by extending (not shown) the surface to be used in a so-called forehead winding form. In this case, the second body fluid impermeable sheet 72 is interposed between the double barrier sheets 64 forming the barrier force hose 60. According to this configuration, the second fluid-impermeable sheet 72 extends until the Norriya cuff 60 stands up! /. Therefore, the body fluid or the diffuser cuffs 60 and 60 that have spread laterally through the top sheet 30 can be obtained. There is also an advantage that side leakage of soft stool can be prevented.

[0078] The body fluid impermeable sheet 70 can be provided with a display section for product name, function description, character, pattern, etc., and this display section has a notification function for informing that urination has occurred. May be.

[0079] (Barrier first effort)

Barrier force hose 60, 60 provided on both sides of the product is a force provided to prevent urine and soft stool that move laterally along the top sheet 30 and prevent side leakage. Element.

[0080] The illustrated barrier strength hoop 60 is a doubled water-repellent nonwoven sheet, covers the folded portion of the top surface 30 from the back side of the absorbent body 56, and protrudes to the front side. It is formed so that. In order to prevent urine from moving laterally on the top sheet 30, a second fluid-impermeable sheet 72 is interposed between the double barrier sheets 64 forming the barrier fist 60. Yes. Further, 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 force hose 60 projecting to the surface side.

[0081] Further, the shape of the barrier first force hose 60 itself can be appropriately designed. In the illustrated example, an elastic elastic member, for example, a rubber thread 62 is stretched under the tip and middle portions of the protruding portion of the barrier cuff 60. The cuffs 60 are erected by the contraction force during use. The middle part of rubber thread 62 in the middle is positioned on the center side of thread rubbers 62 and 62 at the front end and fixed to the front and rear ends of topsheet 30. The side rises obliquely toward the center side, and the tip part rises obliquely outward from the middle part.

[0082] (Absorbing element)

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

[0083] (absorber)

As the absorbent 56, in addition to the one made of cotton-like pulp, the one having the aggregate force of the filaments 52, 52, etc. can be used.

Next, an embodiment of the stretchable part forming method and apparatus according to the present invention will be described with reference to FIGS.

As shown in FIG. 7, the expansion / contraction part forming apparatus according to the present invention is connected to the ultrasonic vibration source 2 and the ultrasonic vibration source 2 to increase the vibration amplitude from the ultrasonic vibration source 2. A horn 3 and an anvil roll 4 arranged opposite to the horn 3 are provided. The ultrasonic vibration source 2 is fixed to a pressure arm (not shown), and the height can be adjusted. In addition, guide rolls 5 and 5 for preventing slack 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.

[0086] Although not shown, in order to prevent looseness of the continuous sheet 1 in a state where the elastic elastic members 12C, 12C, ... are sandwiched between the nonwoven fabrics, the continuous sheet 1 is provided on the outer side of the guide roll. In order to keep the tension constant, it is more preferable to use tension control such as a step roll.

[0087] The continuous sheet 1 is formed by laminating and fixing two or three or more breathable water-repellent nonwoven fabrics, and includes an inner layer (inner sheet) 12H and an outer layer (outer sheet) 12S. A plurality of elastic elastic members 12C, 12C,... Arranged in parallel are sandwiched between them. The nonwoven fabric can be made of polypropylene resin (PP), polyethylene resin (PE), polyethylene terephthalate resin (PET), or a composite of these. Furthermore, the continuous sheet 1 is not limited to a nonwoven fabric, and a film made of polyethylene resin or the like can be used as long as it can be fixed by heat welding or ultrasonic welding, or a combination of a nonwoven fabric and a film can be used. .

[0088] Further, the elastic elastic member 12C has an elastic property and has a tension together with the surrounding nonwoven fabric. A known elastic yarn can be used as long as it can be fixed with force. 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 rubbers and elastomers based on mixtures of these with other polymers such as polystyrene or polyolefins can be used. It is also possible to use elastic yarns from segmented polyester or polyether urethane urea.

[0089] The thickness of the elastic elastic member 12C can be arbitrarily set. The cross-sectional shape is not limited to a circle, but can be freely selected from an ellipse, a rectangle, and other geometric shapes.

[0090] Furthermore, the elastic elastic member 12C is not limited to a thread-like member, and although not shown, a wide ribbon-like member may be used. In the case of a ribbon, it is preferable that both ends in the width direction are welded to the sheet together with the inner layer 12H and the outer layer 12S. In the case of a net shape, it is preferable that the inner layer 12H and the outer layer 12S are welded in the vicinity of both ends in the width direction even for an elastic yarn that is orthogonal to only the elastic yarn in the tensile 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. This is not preferable because it may cause

[0091] As shown in FIGS. 8 (1) and (2), a plurality of protrusions 4A, 4A,... Are formed on the outer peripheral surface of the anvil roll 4 as ultrasonic welding surfaces. A groove having a predetermined depth is formed between the protrusions 4A, 4A,. The horn 3 and the projection 4A of the anvil roll 4 pinch the continuous sheet 1, and the inner layer 12H and the outer layer 12S of the continuous sheet 1 are welded by the welding part 11 as shown in FIGS. 9 (1) and (2). Force S, 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 figure, the inner layer 12H may be positioned at the upper portion, the inner layer 12H may be positioned at the lower portion, and the outer layer 12S may be positioned at the upper portion. The same applies to this point.

[0092] The distance between the protrusion 4A in the width direction (axial direction) of the anvil roll 4 and the protrusion 4A is shown in Fig. 8 (1) and

As shown in (2), outside the cross section of 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 diameter (width). In the case of disposable diapers, as elastic elastic members, it is common to fix polyurethane thread rubber with a thickness of about 400-1000 dtex to a sheet in a stretched state 2 to 3 times. In this state, the outer diameter of the elastic elastic member 12C is approximately 0.18-0.22 mm, and the interval between the protrusions 4A, 4A,... Is preferably set to 0 · 9∼; . More preferably, it is preferably 0.9 to 1 times (excluding 1) the outer diameter of the cross section of the elastic elastic member 12C in the state of being pulled in the longitudinal direction.

[0093] As shown in FIGS. 8 (1) and (2), the grooves between the protrusions 4A, 4A,... Are for accommodating the elastic elastic members 12C so that the elastic elastic members 12C are not constricted by the protrusions. It is. Therefore, the interval between the adjacent grooves coincides with the arrangement interval between the adjacent elastic elastic members 12C, 12C,. Further, the depth of the groove between the protrusions 4A, 4A,... May be deep enough to accommodate the elastic stretch member 12C and deep enough that the continuous sheet 1 does not sag excessively.

[0094] As shown in FIGS. 8 (1) and (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 set so that a tensile force is applied in the longitudinal direction. 1 to 1 times the outer diameter of the cross section of the elastic elastic member 12C under load. 1. When it is set to 1 time, when it is guided between the anvil roll 4 and the horn 3 in which the projections 4A are arranged in a lattice shape, the elastic elastic member With the member 12C in the groove, the inner layer 12H and the outer layer 12S of the continuous sheet 1 are compressed and ultrasonically welded by the protrusion 4A and the horn 3. As a matter of course, since the elastic elastic member 12C is accommodated in the groove, the elastic elastic member 12C having a tensile force is not compressed by the protrusion 4 and the horn 3.

[0095] 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. After that, when the load is removed (no tension), as shown in FIGS. 10 (1) and (2), the cross-sectional outer diameter of the elastic elastic member 12C becomes large, and the inner layer 12H and the outer layer 12S are welded. The pressing force S is applied by the portion 11 so as to sandwich the width direction of the elastic elastic member 12C from both sides. As a result, the elastic elastic member 12C is fixed only by the frictional force between the inner and outer layers 12H and 12S without using an adhesive. [0096] Thereby, deterioration of the elastic elastic member 12C due to the adhesive can be prevented. In addition, since the elastic elastic member 12C is not bonded, an expansion / contraction portion that ensures air permeability and softness can be formed. In addition, since the materials themselves are melted and bonded, the fluctuating 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 (2), the protrusions 4B of the anvil roll 4 are arranged in a lattice pattern, and the distance between the protrusions 4B and 4B in the width direction of the anvil roll 4 is In the case of 0.9 to 1 times (excluding 1) the cross-sectional outer diameter of the elastic elastic member 12C with a tensile load applied in the longitudinal direction, both ends of the elastic elastic member 12C in the width direction are As shown in FIGS. 12 (1) and (2), it is ultrasonically welded by the welded 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 between the inner and outer layers 12H and 12S, the width of the elastic elastic member 12C The elastic expansion / contraction member 12C is fixed by the adhesive force at both ends in the direction. Here, since the welding is performed only at the end portion of the elastic elastic member 12C, there is almost no possibility that the elastic elastic member 12C is deteriorated or cut.

The arrangement of the protrusions is not limited to the lattice shape, and may be a staggered array of protrusions 4C as shown in FIG. At this time, the cross-section of the elastic member 12C in a state in which a tensile force is applied in the longitudinal direction between the protrusion 4C and the protrusion 4C adjacent in the oblique direction with respect to the rotation direction of the anvil roll 4 in the width direction. When the outer diameter is 1 to 1; 1. When the diameter is 1 times, the elastic elastic member 12C is fixed only by the frictional force between the inner and outer layers 12H and 12S without using an adhesive. In addition, when the material constituting the exterior sheet 12 is excellent in frictional force, 1. It is possible to fix even if it is 1 or more times. In addition, the outer diameter of the elastic elastic member 12C in a state where a tensile force is applied in the longitudinal direction is 0.9 to 0.9! When doubled (excluding 1), 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 to the frictional force with the inner and outer layers 12H and 12S. .

[0099] It should be noted that if the distance in the width direction (groove width) between the protrusions 4A to 4C and the protrusions 4A to 4C is within the above range with respect to the cross-sectional outer diameter of the elastic elastic member 12C in a state where a tensile force is applied. , Anvil roll 22 protrusions 4A-4C arrangement pattern is not limited to grid or staggered, but other patterns Good.

[0100] The outer diameter of the cross-section of the elastic elastic member 12C with the groove width extended is 0.9 to ~! If the elastic expansion / contraction member 12C is welded and fixed as a double (excluding 1), the retention force of the elastic expansion / contraction member 12C is very high! /, So it is preferable! /, But the elongation rate is high! / Care must be taken because the elastic member 12C is easy to cut. In particular, when the elongation rate is 300% or more, it is not preferable to make the groove width 0.9 to 1 times (excluding 1).

[0101] Also, when the elastic elastic member 12C is fixed only by frictional force without welding, the elastic elastic member 12C and the inner and outer layers 12H and 12S have high friction resistance, or the elastic elastic member 12C has a low elongation rate. In such a case, the force that can expand the groove width to about 1.3 times the cross-sectional outer diameter of the elastic elastic member 12C in the stretched state is usually 1.0 to 2; ~; 1. 1 times is particularly preferred. In this case, the holding force (friction resistance) increases as it becomes closer to 1 ×, but there is also a risk of cutting the elastic elastic member 12C. Needless to say, the groove width needs to be within the above range and smaller than the diameter of the elastic elastic member 12C when it is relaxed. In order to ensure the holding power, the groove width is preferably 70% or less of the diameter of the elastic elastic member 2 when it is relaxed.

[0102] The depth of the groove (the height of the protrusions 4A to 4C) is preferably the same as the width of the groove. Specifically, the depth of the groove is preferably 0.9 to 1.2 times the cross-sectional outer diameter of the elastic elastic member 12C in the stretched state. Most preferred is a range of 1.0 to 1; 1. If it is less than 0 times, the force to hold the elastic member 12C becomes stronger. The elastic elastic member 12C may be welded. In addition, it is not preferable that the depth of the groove is larger than the cross-sectional outer diameter of the elastic elastic member 12C when relaxed. If the inner and outer layers 12H and 12S are easily distorted in the CD direction (axial direction of the anvil) like a non-woven fabric, if the groove is too deep, the inner and outer layers 1 2H and 12S will be stretched during pinching. May be distorted, and there is a risk that sufficient force to sandwich the elastic elastic member 12C cannot be obtained.

[0103] 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 with no corners such as a circle or an ellipse is used, a soft texture can be obtained. If a cornered shape is used and the corner is placed so as to face the elastic elastic member 12C, the elastic elastic member 12C can be retracted (弹 The phenomenon that the elastic stretchable member 12C contracts while being displaced without being fixed by the inner and outer layers 12H and 12S can be more reliably prevented. In this case, the pulling-in is reduced as the angle facing the elastic elastic member 12C is an acute angle. The angle of the angle facing the elastic elastic member 12C is preferably 15 to 120 degrees, and more preferably 30 to 90 degrees.

[0104] 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 0.3 to 1 mm. It is particularly preferred that the thickness 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, if the protrusions 4A to 4C are too large, the texture is lowered. For other shapes, the vertical and horizontal dimensional ratios may be extremely different if they are set based on the area in the case of a circle. Area of the distal end surface of the collision force 4A~4C is preferably a 0. 03~80mm ^2, more preferably from 0. 07~20mm ^2, 0. 07~0. Especially it is preferably from 8 mm ² 0.07 to 0.3 mm 2 is most preferable.

[0105] The distance 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) is generally a force that can be set to about 0.3 to 20 mm. The protrusions 4A to 4C, which are not the ones, may be continuous in the MD direction in a strip shape (linear shape). To balance 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 anchoring of the elastic elastic member 12C, for example, the protrusions 4A to 4C have a circular shape with a diameter of 0.3 to 0.6 mm. If there is, the distance between the protrusions 4A to 4C may be, for example, about 0.3 to 1. Omm in the MD direction and about 0.3 to 3 mm in the CD direction (anvil roll axial direction). Note that the spacing in the MD direction and the spacing in the CD direction of the protrusions 4A to 4C are indicated by DMD and DCD in FIG. 15, respectively.

[0106] When the protrusions 4A to 4C are arranged in the above-described lattice arrangement, 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, so that a high holding force is 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 of the elastic stretchable member 12C being welded or cut decreases, but the holding power also decreases. In the staggered arrangement, rows of protrusions arranged at a predetermined periodic interval in the MD direction are provided with a predetermined interval in the CD direction. The phase of the arrangement period of the protrusions is shifted with respect to the adjacent row, and it may be arranged so that the phase is shifted by 1/2 with respect to the adjacent protrusion row as shown in the figure. In order to obtain a close arrangement, for example, an arrangement with a phase shift of 1/4 may be used. 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.

[0107] In the fixed region of the elastic elastic member 12C, the area ratio of the welded portion 11 with respect to the entire area is preferably 40% or less, and more preferably 30% or less, in order to obtain a soft texture. Most preferably, it is 20% or less. Further, 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 stretchable member 12C, the sheet is squeezed by the shrinkage of the elastic stretchable member 12C, so that a bonding strength higher than the non-fixed region of the elastic stretchable member 12C is required. Accordingly, in the fixed region of the elastic elastic member 12C, the area ratio of the welded portion 11 is preferably 5% or more, more preferably 10% or more.

[0108] 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 a state where a tensile force is applied to the elastic stretchable members 12C, 12C, ... The inner layer 12H and the outer layer 12S are welded at a predetermined interval in the vicinity of both end portions in the width direction, so that the elastic elastic members 12C, 12C,... Are fixed to the outer sheet 12 by the frictional force with the outer sheet 12. The paper diaper which has the expansion-contraction part of the structure to be made can be manufactured.

[0109] Further, as a second embodiment, in a state where a tensile force is applied to the elastic elastic members 12C, 12C, ..., both ends in the width direction of the elastic elastic members 12C, 12C, ..., the inner layer 12H and the outer side The elastic stretch members 12C, 12C,... 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 by being welded to the layer 12S at a predetermined interval. The paper diaper which has the expansion-contraction part of the structure to be made can be manufactured.

[0110] The stretchable part forming method and apparatus therefor according to the present invention are not limited to the stretchable parts such as shearing, barrier one-off fuzz, and gasket cuffs in a pants-type paper diaper. It can also be applied to the formation of stretchable parts such as barrier one-off floss, gasket cuffs, and stretchable tapes, and can also be applied to the formation of stretchable parts such as normal cuffs and gasket cuffs of absorbent articles including napkins. FIG. 15 shows a case where the stretchable portion forming method of the present invention is applied to the elastic stretchable member 12 C used for shearing formation around the trunk of a pant-type paper diaper. In the illustrated form, whether the dorsal elastic elastic member 12C and / or the abdominal elastic elastic member 12C is cut at the center in the width direction (the part overlapping the part having the absorber that absorbs and retains excreta). Or, don't provide it! /, And so on! /, You can continue from one end to the other in the width direction. As shown in FIG. 15, when the elastic expansion / contraction member is provided over a wide range like the waistline portion of the illustrated form, the portion fixed by the welded portion 11 is intermittently arranged in the longitudinal direction (MD direction) of the elastic expansion / contraction member 12C. Provided (that is, the welded portion group region 44 composed of a large number of welded portions 11 formed at the above-described arrangement / interval and the non-welded portion region 45 having no welded portion are arranged in the longitudinal direction of the elastic member 12C (MD direction). ) Alternately), the stretchability is improved and the area of the welded portion 11 is reduced, so that a softer texture and higher air permeability can be obtained. Of course, as shown in FIG. 16, the welded portion group region 44 to be fixed by the welded portion 3 can be continuously provided over the entire longitudinal direction (MD direction) of the elastic elastic member 2.

[0112] Such an intermittent arrangement can be applied even when a large number of elastic elastic members 2 are arranged side by side. However, if the positions in the longitudinal direction (MD direction) of the fixed portions by the welded portions of the elastic elastic members 2 are different, elasticity The wrinkles formed by the contraction of the elastic member 2 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 vertically cuts the elastic elastic members 12C arranged side by side. It is formed alternately in the direction (MD direction). As a result, a beautiful shirring of 皺 (皺) is formed. The width of the welded portion group region 44 (the distance between the centers of the welded portions 11 located at both ends) W44 is preferably about 2 to 1 Omm, more preferably about 3 to 5 mm. The center distance DCT between adjacent welded portion group regions 44 is preferably about 5 to 20 mm. Further, it is more preferable that the relationship of DCT / 2≥W44 is satisfied.

[0113] In the disposable diaper of the present invention, as described above, the inner layer 12H and the outer layer 12S in the stretchable part are bonded by ultrasonic welding or thermal welding without using any adhesive. It is good also as a structure which was passed. Further, as described above, the back elastic elastic member 12C and / or the abdominal elastic elastic member 12C may be cut or not provided at the portion of the exterior sheet 12 that overlaps the absorbent portion 20. In addition, if the elastic expansion member 12C has a high expansion ratio, and if the tensile force applied to the expansion / contraction part is large during use, the elastic expansion / contraction member 12H and 12S can be elastically expanded / contracted sufficiently only by the frictional force with the inner and outer layers 12H and 12S. The member 12C may not be fixed. In that case, at least at one end in the longitudinal direction of the elastic elastic member 12C, the substantially elastic welding members 12D and 12D arranged so as to cut the elastic elastic member 12C arranged in parallel, The elastic elastic 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.

[0114] On the other hand, as can be seen from the above embodiments, the ultrasonic bonding method is suitable for carrying out the stretchable portion forming method of the present invention, but the plain roll and the force facing the embossed roll having unevenness, Therefore, it can also be carried out by using a hot emboss bonding method in which a sheet is crimped by heat and pressure.

[0115] <Evaluation test>

[0116] By the manufacturing method according to the present invention using ultrasonic welding, various stretched sheets were manufactured under the conditions shown in Table 1, and the "softness", "interlaminar adhesion of the sheet", Evaluation was made on “difficult to pull in” and “difficult to cut”.

[0117] As the inner sheet and the outer sheet, a spunbonded nonwoven fabric (one layer, basis weight: 20 g / m ² , thickness: 0 · 18 mm, fineness: 2 · 2 dtex, composition: ΡΕ (sheath) / ΡΡ (core) = 1/1, sheet width: 150 mm). In addition, as elastic elastic member 2, spandex of 470dtex (diameter: 0.31 lmm) was used and stretched to 270% along the lateral direction of the sheet (2.7 times the original length, diameter is 0. 162mm). In addition, 20 elastic stretch members 2 were arranged in parallel with an interval of 5 mm.

[0118] In addition, "softness" is a sensory evaluation compared to a sheet in which an elastic elastic member is fixed with a conventional adhesive, and 9 or more out of 10 subjects are evaluated as soft and ◎. , 7-8 people evaluated as soft! /, ◯, 4-6 people evaluated as soft! /, △, 3 or less evaluated softness, X . In the evaluation of the “sheet interlayer adhesion”, ◎ indicates that the sheet itself was destroyed when the adhered sheet was peeled off by hand. The case where the sheet was partially broken or delaminated with delamination was marked with ◯, the sheet peeled leaving a slight fluff was marked with △, and the sheet that did not adhere substantially was marked with X. "The difficulty

In the evaluation of (the difficulty of pulling), when the sheet is cut, the elastic member from the cut part is lmm or less, ◎◎, 3mm or less is ◎, and 5mm or less , △ for 10 mm or less, and X for 11 mm or more. In the evaluation of “Difficult to cut”, within the range of 100 mm in the length direction of the sheet, ◎ indicates that the number of cutting points is 1 or less, ◯ indicates 5 or less, and △ indicates 10 or less. , 20 or less were designated as Δ to Χ, and 21 or more were designated as X.

[table 1]

Brief Description of Drawings

FIG. 1 is a perspective view of a pants-type diaper.

FIG. 2 is a plan view of the body side of the unfolded diaper.

FIG. 3 is a cross-sectional view taken along line III-III in FIG. FIG. 4 is a plan view of the outer surface side of the unfolded diaper.

FIG. 5 is a schematic cross-sectional view taken along line V-V in FIG.

FIG. 6 is an enlarged view of the shearing part.

FIG. 7 is a schematic view for explaining the stretchable part forming apparatus.

FIG. 8 is a cross-sectional view in the width direction and a cross-sectional view of the first embodiment showing a state in which a continuous sheet is sandwiched between a horn and an anvil roll.

FIG. 9 is a cross-sectional view in the width direction and a cross-sectional view of the first embodiment of the continuous sheet in a state where a tensile force is applied to the elastic elastic member.

FIG. 10 is a cross-sectional view in the width direction and a transverse cross-sectional view of the first embodiment of the continuous sheet in a state where no tensile force is applied to the elastic elastic member.

FIG. 11 is a cross-sectional view in the width direction and a cross-sectional view of the second embodiment showing a state in which a continuous sheet is sandwiched between a horn and an anvil roll.

FIG. 12 is a cross-sectional view in the width direction and a cross-sectional view of the second embodiment of the continuous sheet in a state where a tensile force is applied to the elastic elastic member.

FIG. 13 is a cross-sectional view in the width direction and a transverse cross-sectional view of a second embodiment of a continuous sheet in a state where a tensile force is not applied to an elastic elastic member.

FIG. 14 is a cross-sectional view showing a state in which a continuous sheet is sandwiched between anvil rolls having an array of staggered protrusions.

FIG. 15 is a schematic view showing an application example of the pants-type paper diaper to the waist part shirring.

FIG. 16 is a schematic diagram showing another example of application to the waistline shearing of a pant-type paper diaper.

1 ··· Continuous sheet, 2 ··· Ultrasonic vibration ¾§, 3 · Horne, 4 · Amperero roll, 4A, 4B, 4C… Protrusion, 10 ··· Pants-type disposable diaper , 12 ··· Exterior sheet, 12 mm ··· Joining area, 12 mm · · · Leg circumference, 12S ... Outer layer, 12 mm ··· Inner layer, 12C ... Elastic elastic member, 1 2D ... Welding wire, 12 mm ··· Permeability improving part, 13 ··· Display part, 20 ··· Absorbing part, 30 ··· Top sheet, 40 ··· Intermediate sheet (second sheet), 50 ··· Absorbing element, 56 ··· Absorbing element Body, 58 ... Cover sheet, 60 Barrier force, 64 Barrier sheet, 70 Body fluid impervious sheet (back sheet) ), 72 ···· Second fluid impervious sheet, 80 ··· Retaining sheet, S ··· Shearing.

Claims

The scope of the claims

[1] 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 the 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,

The stretchable part is welded at a predetermined interval in the vicinity of both ends in the width direction of the elastic stretchable member with a tensile force applied to the elastic stretchable member. A paper diaper characterized by being configured to be fixed to an exterior sheet by a frictional force with the exterior sheet.

[2] 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 the object,

The elastic member is formed by welding both end portions in the width direction of the elastic elastic member and the inner layer and the outer layer at a predetermined interval in a state where a tensile force is applied to the elastic elastic member. Is fixed to the exterior sheet by the frictional force with the exterior sheet and the adhesive force at the end in the width direction of the elastic elastic member.

Paper diapers characterized by that.

[3] The paper diaper according to claim 1 or 2, 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.

[4] The force according to any one of claims 1 to 3, wherein the inner layer and the outer layer in the stretchable part are bonded by ultrasonic welding or heat welding without using an adhesive. Paper diapers.

[5] The back elastic stretch member and / or the abdomen elastic stretch member is cut at the portion of the exterior sheet that overlaps the absorbing portion, or is provided, or is provided! The disposable diaper according to any one of claims 1 to 4.

[6] At least one end portion in the longitudinal direction of the elastic elastic member, the elastic elastic member, the inner layer of the exterior sheet, and the outer layer are welded to the elastic elastic member arranged in parallel. The paper diaper according to any one of claims 1 to 5, wherein the side layer is welded and fixed.

[7] Using a continuous sheet with a plurality of elastic elastic members arranged in parallel between the inner sheet and the outer sheet,

A method for forming a stretchable part of an absorbent article, wherein the elastic stretchable member is fixed by intermittently bonding the inner sheet and the outer sheet to a supply direction,

The inner sheet and the outer sheet are intermittently welded in the vicinity of both end portions in the width direction of the elastic elastic member in a state where a tensile force is applied to the elastic elastic member, and the elastic elastic member is fixed to the sheet. The stretchable part forming method.

[8] Using a continuous sheet with a plurality of elastic elastic members arranged in parallel between the inner sheet and the outer sheet,

In a state where a tensile force is applied to the elastic elastic member, both ends in the width direction of the elastic elastic member are intermittently welded to the inner sheet and the outer sheet, and the elastic elastic member is fixed to the sheet. A stretchable part forming method.

[9] Using a continuous sheet with a plurality of elastic elastic members arranged in parallel between the inner sheet and the outer sheet,

A stretchable part forming apparatus for absorbent articles, wherein the elastic stretchable member is fixed by intermittently bonding the inner sheet and the outer sheet in the supply direction with a tensile force applied to the elastic stretchable member. Because

The apparatus includes an ultrasonic vibration source, a horn connected to the ultrasonic vibration source, and an anvil roll disposed to face the horn.

On the outer peripheral surface of the anvil roll, a plurality of protrusions serving as adhesive surfaces are formed,

These protrusions are in a lattice shape and are configured to have the same length as the outer diameter of the cross section of the elastic elastic member in the state in which the space force between the protrusions in the width direction of the anvil roll and the tension is applied. A stretchable part forming apparatus.

These protrusions are staggered, and the width in the width direction between the protrusions adjacent to each other in the oblique direction with respect to the rotation direction of the anvil roll is approximately the same as the outer diameter of the cross section of the elastic elastic member in a state where a tensile force is applied. Configured,

A stretchable part forming apparatus.