JP2020032071A - Underpants type absorbent article - Google Patents

Abstract

To provide an underpants type absorbent article having even and high color development, and an external appearance like an underwear, excellent in aesthetic property.SOLUTION: An underpants type absorbent article is such that: an exterior body is composed of a composite elastic sheet obtained by integrating two nonwoven fabrics with an elastic film arranged between the two nonwoven fabrics by a plurality of deposition points 36a; the exterior body has a plurality of lines in which the plurality of deposition points 36a are aligned in a direction Y orthogonal to an extraction and contraction direction X of the composite elastic sheet; the plurality of lines comprise first lines A and second lines B arranged alternately at equal intervals; a distance Lx between the deposition points 36a in the extraction and contraction direction X of the first line A is 2 mm or less; a deposition point 36b of the second line B is arranged so as to bisect an interval between the two deposition points 36a arranged in the Y direction of the first line A; the nonwoven fabric at a non-skin contact surface side in the two nonwoven fabrics has a clarity of 60% or more and 85% or less, and a basis weight of 10 g/mor more and 20 g/mor less; and the elastic film has a brightness of 70% or less and a basis weight of 20 g/mor more and 40 g/mor less.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a pants-type absorbent article.

Generally, an uncolored white pants-type disposable diaper has a strong impression that a person with a high care level wears it, and therefore a user with a low care level may feel a strong resistance to wear. There is a need for a colored pants-type paper diaper that looks more like underwear in order to reduce the resistance to wearing. Therefore, as the nonwoven fabric of the outer package of the pants-type absorbent article, a material obtained by adding a coloring agent to a raw material resin or a material colored by printing is used. However, since the nonwoven fabric has an unsatisfactory formation, even if it is colored, its coloration is poor, and it is difficult to perform uniform and high-density coloring. In addition, the absorbent body inside may be transparent, which may impair cosmetics.
Pants-type disposable diapers using a current colored nonwoven fabric have little room for improvement in terms of underwear because they are light in color and inferior in cosmetics.

  Then, in order to improve the design property of a pants-type paper diaper, a colored disposable wearing article has been proposed. For example, in Patent Literature 1, the waist panel and the crotch panel are colored substantially all over, and the first region where the crotch panel does not overlap in plan view in the waist panel and the waist panel in plan view in the crotch panel. Of the non-overlapping second region and the third region in which the waist panel and the crotch panel overlap in plan view, in the natural state in which the waist elastic body has contracted, the region having the highest color density and the region having the lowest color density in external appearance It is disclosed that, when the color difference is in the range of 0.1 to 10.0, it is possible to color almost the entire area to improve the design property and to obtain an undergarment-like appearance.

  In Patent Document 2, an elastic film is laminated between a first sheet layer and a second sheet layer opposed to the second sheet layer and exposed on the outer surface of the product, and the first sheet layer and the second sheet layer are spaced apart from each other. It has an elastic film elastic structure which is joined directly or via an elastic film at a large number of arranged sheet joints, and the entire first sheet layer is a non-woven fabric colored in a color other than white, and The entire film is colored in a color having a color difference ΔE of 3.2 or less with respect to the colored portion of the first sheet layer, and a region where these colored portions overlap is visually recognized as a product coloring from the outer surface of the product, so that the film is worn. It is disclosed that color unevenness is suppressed.

JP-A-2006-73578 JP 2017-225508 A

In the invention described in Patent Literature 1, the colored nonwoven fabric is used for the waist panel. Therefore, even if the color density is increased, the beauty is not necessarily good due to uneven formation of the nonwoven fabric. Further, in the invention described in Patent Document 2, the first sheet layer and the elastic film exposed on the outer surface of the product are colored, so that there is a concern about an increase in cost.
In addition, a composite stretch sheet in which a stretch film is sandwiched between nonwoven fabrics is usually used for the exterior body. In the nonwoven fabric bonded to the stretchable film in the stretched state, wrinkles and folds are generated in the natural length state in which the stretchable film is contracted, and the opacity increases in the portion where the fibers at the crests and folds of the folds overlap. When the nonwoven fabric is colored, the color of the stretchable film and the nonwoven fabric do not overlap with each other, resulting in a light color tone. On the other hand, in the case of a non-colored nonwoven fabric, there is a problem that unevenness in color occurs because the portion where the fibers of the crests and folds of the folds are overlapped becomes whitish.
Further, if the basis weight of the nonwoven fabric is increased, the coloring property can be improved, but there is a problem that the nonwoven fabric is easily stuffed and wearing comfort is poor.
The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a pants-type absorbent article having uniform and high coloring properties, excellent aesthetics, and an appearance like underwear.

The present inventors have conducted intensive studies and found that in pants-type absorbent articles, in order to eliminate color tone unevenness of a colored stretchable sheet and to achieve uniform and high color development, the height of folds and wrinkles should be reduced. Is important.
Further, in Patent Document 2 described above, the area and the area ratio of the welded portion are described as conditions for regularly arranging the wrinkles for the undergarment-like appearance and reducing the size thereof. The inventors have also found that the arrangement is important, and have led to the present invention.
That is, the present invention provides an absorbent pad having a liquid-permeable topsheet, an absorbent core containing a superabsorbent polymer, and a liquid-impermeable backsheet in this order, and the liquid-impermeable backsheet of the absorbent pad. A pants-type absorbent article comprising: an outer body disposed on a side and having an abdominal part, a crotch part, and a back part, wherein the outer body is formed between two nonwoven fabrics and the two nonwoven fabrics. The composite body is constituted by a composite stretch sheet in which a stretchable film arranged in the composite stretch sheet is integrated by a plurality of welding points, and the exterior body is arranged in a direction in which the plurality of welding points are orthogonal to the stretching direction of the composite stretch sheet. A plurality of rows, the plurality of rows, the first row and the second row are alternately arranged at equal intervals, between the welding points in the expansion and contraction direction of the first row Is 2 mm or less, and the welding point of the second row The non-woven fabric on the non-skin contact surface side of the two non-woven fabrics is at least 60% or more, and is arranged between the two welding points of the first row in the orthogonal direction. % or less have a transparency and 10 g / ^{m 2} or more 20 g / ^{m 2} or less of the mass per unit area, the stretchable film, pant-type absorbent having 70% or less of the brightness and 20 g / ^{m 2} or more 40 g / ^{m 2} or less of the mass per unit area It is a sexual article.

An absorbent pad having a liquid-permeable top sheet, an absorbent core containing a superabsorbent polymer, and a liquid-impermeable back sheet in this order; and an absorbent pad disposed on the liquid-impermeable back sheet side of the absorbent pad, A pants-type absorbent article comprising an exterior body having a side portion, a crotch portion, and a belly side, wherein the exterior body is disposed between two nonwoven fabrics and the two nonwoven fabrics. A film and a composite stretch sheet are formed by being integrated by a plurality of welding points, and the exterior body includes a plurality of rows in which the plurality of welding points are arranged in a direction orthogonal to the stretching direction of the composite stretch sheet. A plurality of the rows, a first row arranged at equal intervals in the expansion and contraction direction, a second row and a third row arranged so as to divide the first row into three equal parts And the welding point in the expansion and contraction direction of the first row Is 3 mm or less, the welding points of the second row and the third row are arranged between two welding points of the first row arranged in the orthogonal direction, and The welding points of the second row and the third row are arranged so as to divide the welding points in the orthogonal direction of the first row into three equal parts, and at least the non-woven fabric of the two nonwoven fabrics The nonwoven fabric on the skin contact surface side has a transparency of 60% or more and 85% or less and a basis weight of 10 g / m ² or more and 20 g / m ² or less, and the stretchable film has a lightness of 70% or less and 20 g / m ² or less. A pants-type absorbent article having a basis weight of 40 g / m ² or less.

  ADVANTAGE OF THE INVENTION According to this invention, the underpants-type absorbent article which is uniform and high in coloring property, is excellent in cosmetics, and has an undergarment-like appearance can be obtained.

It is a perspective view showing one embodiment of a pants type absorbent article of the present invention. FIG. 2 is a development view of the pants-type absorbent article shown in FIG. 1. Is _X 1 -X ₁ cross-sectional view in FIG. It is the schematic of the ultrasonic welding apparatus which sticks a nonwoven fabric and an elastic film. It is a top view showing the example of arrangement of the welding point of the underpants type absorptive article of one embodiment of the present invention. Is _X 2 -X ₂ cross-sectional view in FIG. Is a _Y 2 -Y ₂ cross-sectional view in FIG. It is a top view which shows the other example of arrangement | positioning of a welding point. Is _X 3 -X ₃ cross-sectional view in FIG. It is a top view showing other embodiments of a pants type absorbent article of the present invention. It is a figure showing the example where all the welding points were arranged at equal intervals.

  Hereinafter, embodiments of the present invention will be described in detail. However, the following embodiments are presented for illustrative purposes, and the present invention is not limited to the embodiments described below.

[Pants type absorbent article]
One embodiment of the pants-type absorbent article of the present invention will be described with reference to the drawings.
As shown in FIG. 1, the pants-type absorbent article 10 according to the present embodiment includes an absorbent pad 20 having a substantially band-like shape in the front-rear direction that covers the wearer's crotch from front to back, and a non-skin of the absorbent pad 20. And an exterior body 30 disposed on the contact surface and having a pants-like shape.
Hereinafter, the details of the absorbent pad 20 and the exterior body 30 will be described.

(Absorbent pad)
As shown in FIGS. 2 and 3, the absorbent pad 20 includes a liquid-permeable top sheet 21, an absorbent core 22 containing a superabsorbent polymer, and a liquid-impermeable back from the wearer's skin contact surface side. Sheets 23 are provided in this order, and three-dimensional gathers 24 are provided on the surface. As shown in FIG. 3, the three-dimensional gather 24 includes an elastic member 24a, for example, thread rubber, and a sheet 24b such as a nonwoven fabric. By having three-dimensional gathers, lateral leakage of bodily fluids or the like can be prevented.

-Liquid permeable top sheet-
The liquid-permeable topsheet 21 may be formed from a substrate having a liquid-permeability such that the bodily fluid moves to the absorbent core 22, and for example, a nonwoven fabric such as a thermal-bonded nonwoven fabric, a spun-bonded nonwoven fabric, or a thermal-bonded nonwoven fabric. It is made of a material that has a soft touch and does not irritate the skin, such as a hydrophilic nonwoven material such as a composite nonwoven fabric with spunbond laminated. Further, the liquid-permeable top sheet 21 may be subjected to embossing or perforation on the surface in order to improve the liquid permeability. As a method for performing the embossing or the perforation, a known method can be implemented without limitation. Further, in order to reduce irritation to the skin, the liquid-permeable top sheet 21 may contain a lotion, an antioxidant, an anti-inflammatory component, a pH adjuster, an antibacterial agent, a humectant, and the like. Further, from the viewpoint of strength and workability, the basis weight of the liquid-permeable top sheet 21 is preferably 18 g / m ² or more and 40 g / m ² or less. The shape of the liquid-permeable topsheet 21 is not particularly limited, but may be any shape as long as it covers the absorbent core 22 and is necessary to guide the body fluid to the absorbent core 22 so as not to leak.

-Liquid-impermeable back sheet-
The liquid-impermeable back sheet 23 may be formed using a liquid-impermeable base material such that the bodily fluid held by the absorbent core 22 does not wet clothing, and may be air-permeable or air-impermeable. It is formed from a resin film. Here, examples of the resin film that can be used include polyester, polyvinyl alcohol, polyethylene, polypropylene, and a composite film of polyethylene and polypropylene. From the viewpoint of strength and workability, the basis weight of the liquid impermeable back sheet 23 is preferably 15 g / m ² or more and 40 g / m ² or less. In order to prevent stuffiness at the time of mounting, it is preferable to use a resin film having air permeability as the liquid impermeable back sheet 23. In order to provide the liquid impermeable back sheet 23 with air permeability, for example, a filler may be added to the resin film of the base material, or the liquid impermeable back sheet 23 may be embossed. In addition, calcium carbonate can be mentioned as a filler, and the compounding method can be performed without limitation by a known method.

-Absorber core-
The absorbent core 22 contains an absorbent fiber as a base material and a superabsorbent polymer (SAP). The absorbent fibers may be those generally used for absorbent articles such as sanitary napkins, diapers, urine absorbing pads, and the like, for example, fluff pulp, cotton, rayon, acetate, tissue, absorbent paper, hydrophilic nonwoven fabric Can be mentioned. Among these, it is preferable to use fluff pulp from the viewpoint of absorbability. As fluff pulp, wood pulp, synthetic fiber, polymer fiber, non-wood pulp, or the like that has been defibrated into cotton can be mentioned. The absorbent fiber of the absorbent core 22 preferably has a basis weight of 50 g / m ² or more and 800 g / m ² or less so as not to impair the absorption performance and the touch.

The superabsorbent polymer used for the absorbent core 22 may be any polymer that can absorb bodily fluids and prevent backflow, such as sodium polyacrylate, polyaspartate, and (starch-acrylic acid). Those formed from materials such as graft copolymers, (acrylic acid-vinyl alcohol) copolymers, (isobutylene-maleic anhydride) copolymers and saponified products thereof can be used. Among these, sodium polyacrylate is preferred from the viewpoint of the amount of absorption per weight. The SAP amount of the absorbent core 22 is preferably 10 g / m ² or more and 500 g / m ² or less, and is preferably 15 mass% or more and 50 mass% or less so as not to impair the absorption performance and the touch. Is preferred.

  The form of the absorbent fibers and the SAP in the absorbent core 22 is preferably a form of a laminated mat formed by mixing SAP particles in the absorbent fibers. Further, it is preferable to wrap the absorbent core 22 in a carrier sheet for the purpose of preventing leakage of the SAP particles and stabilizing the shape of the absorbent core 22. The substrate of the carrier sheet may be any material having hydrophilicity, and examples thereof include hydrophilic nonwoven fabrics such as tissues, absorbent papers, and airlaid nonwoven fabrics. When a plurality of carrier sheets are provided, the base materials of the carrier sheets may be the same or different.

The absorbent core 22 may be composed of two or more absorbers, for example, a laminate of an upper absorbent body and a lower absorbent body. In this case, the size of the upper absorber and the lower absorber in the longitudinal direction and the width direction may be such that the size of the upper absorber is larger than the size of the lower absorber, and the size of the upper absorber is the same as the size of the lower absorber. And the size of the upper absorber may be smaller than the size of the lower absorber.
In the present embodiment, the three-dimensional gathers 24 are provided, but need not be provided.

(Exterior)
As shown in FIGS. 2 and 3, the exterior body 30 is disposed on the liquid-impermeable back sheet 23 side of the absorbent pad 20, and has an abdominal part 30a, a crotch part 30b, and a back part 30c. The exterior body 30 is composed of a composite elastic sheet in which two nonwoven fabrics 31 and 33 and an elastic film 32 disposed between the two nonwoven fabrics 31 and 33 are integrated by a plurality of welding points 36. (See FIG. 4). The exterior body 30 is folded in two so that the absorbent pad 20 is on the inside, and the abdominal part 30 a and the back part 30 c are joined by the side seal part 35.

The composite stretchable sheet has a permeability of 20 cm ³ / cm ² · sec or more measured in accordance with JIS L 1096-A (Fragile method): 1990 in a non-stretched state. If the air permeability is less than 20 cm ³ / cm ² · second, it becomes easy to get stuffy when worn. The air permeability can be freely changed depending on the thickness, the weaving density, the weight per unit area, the opening area ratio of the opening provided in the elastic sheet, and the like of the fibers and yarns of the nonwoven fabric constituting the composite elastic sheet. .

In addition, the composite stretch sheet has a permeability of 50 cm ³ / cm ² · sec or more measured according to JIS L 1096-A (Fragile method): 1990 when stretched by 150% in the stretch direction. Here, “extending 150% in the stretching direction” refers to the ratio of the length that has been increased by stretching to the natural length in the non-stretched state. That is, when the non-stretchable composite stretchable sheet having a natural length of 10 cm is stretched by 15 cm in the stretching direction, the stretching is 15/10 × 100 = 150%. When the air permeability is less than 50 cm ³ / cm ² · second, a part used in a stretched state, for example, a part around the hips becomes stuffy when worn.

  The pants-type absorbent article 10 can have a pair of left and right leg gathers 34 extending from the abdominal part 30a to the back part 30c via the crotch part 30b. As shown in FIG. 3, the leg gather 34 is formed by an elastic member 34a, for example, a thread rubber and a sheet 34b such as a nonwoven fabric. By providing the leg gathers 34, as shown in FIG. 2, it is possible to expand and contract not only in the expansion and contraction direction X (horizontal direction when worn), but also in a direction Y perpendicular to the expansion and contraction direction (vertical direction when worn). In addition, the fit around the inseam is improved.

-Non-woven fabric-
In the pants-type absorbent article 10 of the present invention, at least the nonwoven fabric 33 on the non-skin contact surface side among the two nonwoven fabrics 31 and 33 has a transparency of 60% or more and 85% or less, and 10 g / m ² or more and 20 g / m ^2. It has the following basis weight.
In the present invention, the color of the stretchable film 32 is not erased by reducing the ridges of the folds of the nonwoven fabrics 31 and 33. For this reason, if the transparency of the nonwoven fabric itself is low, the tint becomes poor. From such a viewpoint, the transparency of the nonwoven fabrics 31 and 33 is 60% or more and 85% or less.
Note that the transparency of the nonwoven fabric is a value measured using (CMS-35SP, trade name, Murakami Color Research Laboratory).

In addition, when the thickness of the nonwoven fabrics 31 and 33 is too small, the amount of the resin is small and the strength of welding is likely to be reduced. Also, as the thickness increases, the color of the stretchable film becomes more difficult to transmit, and the color developability deteriorates. From such a viewpoint, the basis weight of the nonwoven fabrics 31 and 33 is 10 g / m ² or more and 20 g / m ² or less.
When a nonwoven fabric is bonded to both sides of an elastic film by ultrasonic welding or the like as in the present invention, a hole is formed in the elastic film, and the resin of the nonwoven fabric on both sides is melted and bonded through the hole. The non-woven fabric 33 on the non-skin contact surface side may be the same as the non-woven fabric 31 on the absorbent pad 20 side. However, since the non-woven fabrics 31 and 33 are also a resin source for welding, if the thickness becomes too thin, the resin becomes less and the welding becomes less. There is a great possibility that the strength will decrease. Therefore, when the outer nonwoven fabric 33 is set to 10 g / m ² , the inner nonwoven fabric 31 is preferably at least 20 g / m ² .

  The nonwoven fabrics 31 and 33 are nonwoven fabrics such as a thermal bond nonwoven fabric, an air-through nonwoven fabric, and a spunbond nonwoven fabric, preferably an air-through nonwoven fabric or a spunbond nonwoven fabric, and use a nonwoven fabric made of a thermoplastic resin such as polypropylene, polyester, or polyethylene. Can be. Spunbond is particularly desirable. The nonwoven fabrics 31 and 33 may be the same or different.

-Stretch film-
The stretchable film 32 has a brightness of 70% or less and a basis weight of 20 g / m ² or more and 40 g / m ² or less.
Note that the brightness is a value measured using (trade name “CMS-35SP”, Murakami Color Research Laboratory).
The stretchable film 32 only needs to have stretchability. For example, a styrene-based elastomer, a polyester-based elastomer, a polyolefin-based elastomer, a polyurethane-based resin, a polyamide-based resin, or the like contains a pigment in an amount of 3% to 10%. It is possible to use a film that has been subjected to a heat treatment. Among them, a polyurethane resin film is preferable from the viewpoint of cost and stretchability.

  The stretchable film 32 preferably has a plurality of openings in plan view. The shape of the opening can be a square, a rectangle, a circle, an ellipse, and a polygon such as a triangle and a pentagon, but is preferably a rectangle such as a square and a rectangle. This opening has a short side of 0.1 mm or more and 0.3 mm or less along the stretching direction of the stretchable film 32 and a long side of 0.3 mm or more and 0.7 mm or less along a direction orthogonal to the stretching direction. Preferably, adjacent openings are separated from each other by 0.5 mm or more and 1.0 mm or less along the stretching direction, and 0.3 mm or more and 0.7 mm or less along the direction perpendicular to the stretching direction. Is preferred. The opening ratio of the stretchable film 32 is preferably 7% or more and 14% or less. By adjusting the size of the opening and the opening ratio of the stretchable film 32 as described above, it is possible to appropriately balance the strength of the stretchable film 32 and the air permeability.

-Lamination of elastic film and non-woven fabric-
Next, the bonding of the nonwoven fabrics 31 and 33 and the stretchable film 32 will be described with reference to FIG. FIG. 4 is a schematic view of an ultrasonic welding device for bonding a stretchable film and a nonwoven fabric.
As shown in FIG. 4, the nonwoven fabrics 31 and 33 are fed at the line speed of the manufacturing apparatus 40, and the stretchable film 32 is fed by nip rolls 41 and 42 rotating at a peripheral speed lower than the line speed. The nip rolls 45 and 46 ahead of it are rotating at the same peripheral speed as the line speed. The elastic film 32 is welded to the nonwoven fabrics 31 and 32 by the anvil roll 43 and the horn 44 of the ultrasonic welding device facing the anvil roll 43. In the subsequent steps, the stretchable film 32 flows at the same speed as the nonwoven fabrics 31 and 33. Therefore, it is between the nip rolls 41 and 42 and the horn 44 that the stretchable film 32 is stretched due to the speed difference between the feeding speed of the stretchable film 32 and the line speed. The longer the distance is, the longer the stretchable film 32 is necked in. Therefore, it is preferable that the distance is as short as possible, and it is desirable that the length be within 1 m at most.
Protrusions are regularly formed on the surface of the anvil roll 43, and the nonwoven fabrics 31 and 33 and the stretchable film 32 are welded by being subjected to ultrasonic vibrations under a load while being sandwiched between the protrusions and the horn 44. This projection serves as a welding point 36. The feel and properties of the composite stretch sheet change depending on the arrangement and spacing of the protrusions on the surface of the anvil roll 43.

−Welding point−
The arrangement of the welding points of the exterior body 30 of the pants-type absorbent article 10 of the present embodiment will be described with reference to FIG.
FIG. 5 is a plan view showing an example of the arrangement of welding points formed on the exterior body 30 of the pants-type absorbent article 10. Here, the welding point in the first row A is described as 36a, and the welding point in the second row B is described as 36b.
The exterior body 30 of one embodiment has a plurality of welding points 36a in a direction Y (hereinafter, simply referred to as a Y direction) perpendicular to an expansion / contraction direction X (hereinafter, may be simply referred to as an X direction) of the composite elastic sheet. And a second row B in which a plurality of welding points 36b are arranged in a direction Y orthogonal to the stretching direction X of the composite stretchable sheet. A and a second row B are alternately arranged at equal intervals in the expansion / contraction direction X.
Welding point 36b of the second row B are arranged between D _Y of the first column A 2 two welding points 36a arranged in the Y direction so as to bisect.
The welding points 36a and 36b of the present embodiment have the same shape and size.

Normally, as shown in FIG. 11, when all the welding points 76 are arranged at equal intervals in the vertical and horizontal directions, after the elastic film 32 and the nonwoven fabrics 31 and 33 are bonded, the stretching is released and the elastic film has a natural length. In this case, although the nonwoven fabrics 31 and 33 slack between the welding points 76, a fold can be formed. In the present invention, as shown in FIG. 6, two ridges 37 are formed. This is because, as shown in FIG. 7, in between the two welding points 36a in the Y direction of the first row A _(Y 2 -Y ₂ section of FIG. 5), the welding points nonwoven 31 and 33 become valleys 36a In FIG. 6, both ends are suppressed and the flat surface remains (the valley 38 between the peaks 37 in FIG. 6), so that there are _two peaks in the X ₂ -X ₂ cross section. That is, the folds are formed such that the rows A and B form valleys, and the height of the folds is also about half that of the case of FIG.

As shown in FIG. 11, if the welding points 76 are all arranged at equal intervals in the vertical and horizontal directions, the distance L between the welding points 76 in the expansion / contraction direction X can be adjusted to the same height as the fold in the first embodiment. the need to be about 1/2 of the width D _x of the above embodiments. Usually, since the stretchable film opens at the welding point, there is a disadvantage that the completed composite stretchable sheet is more likely to be torn as the number of welding points increases. Also, it feels hard.

  The present invention prevents the nonwoven fabrics 31 and 33 in the surface layer from erasing the color of the stretchable film 32 by minimizing the folds generated in the composite stretchable sheet, thereby increasing the uniformity and color development of the pants-type absorbent article 10. Is what you do. Therefore, in the present invention, the distance Dx in the expansion and contraction direction X of the welding point 36a is 2 mm or less. Thereby, the height h (see FIG. 6) of the peak 37 on one surface (one of the nonwoven fabrics 31 and 33) of the composite elastic sheet can be made 1 mm or less. The height h of the peak 37 is preferably 0.3 mm or more and 0.6 mm or less.

If the length Lx in the expansion / contraction direction is long, the welding point 36 may cause a decrease in stretchability. Therefore, the shape of the welding point 36 may be a circle, a rectangle long in the Y direction, or a combination of a rectangle long in the Y direction and a circle. In the case of a circular shape, the diameter is preferably 0.2 mm or more and 0.6 mm or less. In the case of a rectangle, the length Lx in the X direction is preferably 0.2 mm or more and 0.6 mm or less. If it is smaller than 0.2 mm, the durability of the welding point 36 and the protrusion of the anvil roll 43 will be weak. If it is larger than 0.6 mm, it not only affects the stretchability, but also reduces the area of the stretchable film 32 and weakens the color.
The length _{L Y} in the Y-direction is more preferably preferably at 1mm or more than 6mm is 2mm or more 5mm or less.
The distance Dx in the X direction between the welding points 36a affects the tensile stress of the composite elastic sheet, and can be selected in a range of 0.5 mm or more and 2 mm or less according to a desired tensile stress.
The distance D _Y in the Y direction is too large, the mountain between the welding point in the elongating and contracting direction X becomes one, it is preferably 0.5mm or more 5mm or less.

Next, another embodiment of the pants-type absorbent article will be described with reference to FIG. This embodiment is different from the above embodiment only in the arrangement of the welding points. Therefore, description of elements other than the welding point is omitted.
As shown in FIG. 8, in the present embodiment, between the first row A in which the welding points 36a are arranged in the direction Y orthogonal to the stretching direction X of the composite stretchable sheet, There are a plurality of second and third rows B and C arranged so as to divide the expansion direction X of one first row A into three equal parts.
The welding point 36b of the second row B and the welding point 36c of the third row B are arranged between two welding points 36a of the first row A arranged in the Y direction. Further, the welding point 36b of the second row B and the welding point 36c of the third row B are the same as the center line Xb of the welding point 36b in the X direction and the center line Xc of the welding point 36c in the X direction. a trisect located the distance D _Y between two welding points 36a of a, the Y direction of the Y direction of the center line Yb and welding point 36c of the welding point 36b centerline Yc is, the two first the distance D _x between the welding point 36a in column a are arranged in a three equally divided positions.

By arranging the welding points as shown in FIG. 8, three ridges are formed between the two welding points 36a in the expansion / contraction direction X as shown in FIG.
The distance Dx in the expansion / contraction direction X of the welding point 36a is 3 mm or less. Since the distance Dx in the X direction affects the tensile stress of the composite elastic sheet, the distance Dx is 0.5 mm or more and 3 mm or less, and can be determined by a desired tensile stress. For example, by making the portion corresponding to the waist wider and stronger, and narrowing and weakening in the other regions, a pants-type absorbent article that is hard to shift and has a comfortable fit can be obtained.

Further, in the present embodiment, the size of the welding point is different between the welding point 36a and the welding points 36b and 36c. As shown in FIG. 7, the welding strength does not have to be so strong only to make the nonwoven fabric flat (valley) in the Y direction, so that the area of the welding point can be further reduced. Thereby, since the area of the hole generated in the welded portion can be reduced, the area of the stretchable film 32 as the colored layer can be left more, and the pants-type absorbent having uniform and high color developing properties Articles can be obtained.
The length _{L X} of the expansion and contraction direction of the second welding point 36b and the third column C column B 36c is preferably 0.2mm or more 1.2mm or less, at 0.5mm or 1.0mm or less More preferably, there is. The length _{L Y} in the Y-direction of the welding point 36b and 36c is preferably 1mm or more than 6mm, and more preferably 2mm or more 5mm or less.

  According to the present invention, by having the above-mentioned welding point, the coloring property of the exterior body 30 can be made uniform and high without using a colored nonwoven fabric as the exterior body 30. Further, according to the present invention, the wrinkles of the exterior body 30 can be reduced, so that a pants-type absorbent article which is excellent in cosmetics without color tone unevenness in the exterior body 30 can be obtained. In addition, since the wrinkles have a cloth-like appearance due to small wrinkles, a pants-type absorbent article that looks like underwear can be obtained.

  The pants-type absorbent article of the present invention is not limited to the exterior body 30 in which the abdominal part 30a, the crotch part 30b, and the back part 30c are integrated as shown in FIG. 2, but the pants-type absorbent article shown in FIG. Like the article 50, the exterior body 60 may be formed by joining three parts of the abdomen 60a, the crotch 60b, and the back 60c.

10, 50 Pants-type absorbent article 20 Absorbent pad 30, 60 Outer body 30a, 60a Abdomen 30b, 60b Crotch 30c, 60c Back 31, 31, Non-woven fabric 32 Elastic film 34 Leg gather 24a, 34a Elastic member ,
24b, 34b nonwoven sheet 35 side sealing portions 36,36a, 36b, 36c, 76 welding point of the welding point 37 crest 38 trough 41, 42, 45, 46 nip 43 anvil roll 44 horn D, _{D X} X direction (stretching direction) distance D Y _Y-direction distance L the length of the expansion and contraction direction of the _X welding point L _Y direction length of the perpendicular to the stretching direction of the welding point between the welding point (a direction orthogonal to the stretch direction) between

Claims (2)

A liquid-permeable topsheet, an absorbent core containing a superabsorbent polymer, and an absorbent pad having a liquid-impermeable backsheet in this order,
A pants-type absorbent article comprising: an absorbent pad disposed on the liquid-impermeable back sheet side of the absorbent pad; and an abdominal part, a crotch part, and an exterior body having a back part.
The exterior body is composed of a composite stretch sheet in which two nonwoven fabrics and a stretchable film disposed between the two nonwoven fabrics are integrated by a plurality of welding points,
The exterior body has a plurality of rows in which the plurality of welding points are arranged in a direction orthogonal to a stretching direction of the composite stretching sheet,
The plurality of rows, the first row and the second row are arranged alternately at equal intervals,
The distance between the welding points in the expansion and contraction direction of the first row is 2 mm or less;
The welding points of the second row are arranged so as to bisect the two welding points arranged in the orthogonal direction of the first row,
At least the non-skin contact surface side non-woven fabric of the two non-woven fabrics is a 85% 60% less transparency and 10 g / ^{m 2} or more 20 g / ^{m 2} or less of the mass per unit area,
A pants-type absorbent article, wherein the stretchable film has a brightness of 70% or less and a basis weight of 20 g / m ² or more and 40 g / m ² or less. A liquid-permeable topsheet, an absorbent core containing a superabsorbent polymer, and an absorbent pad having a liquid-impermeable backsheet in this order,
A pants-type absorbent article comprising: an absorbent pad disposed on the liquid-impermeable backsheet side of the absorbent pad; an abdominal part, a crotch part, and an exterior body having an abdominal part;
The exterior body is composed of a composite stretch sheet in which two nonwoven fabrics and a stretchable film disposed between the two nonwoven fabrics are integrated by a plurality of welding points,
The exterior body has a plurality of rows in which the plurality of welding points are arranged in a direction orthogonal to a stretching direction of the composite stretching sheet,
A plurality of the rows, a first row arranged at equal intervals in the expansion and contraction direction, a second row and a third row arranged to divide the first row into three equal parts Have
The distance between the welding points in the expansion and contraction direction of the first row is 3 mm or less;
The welding points of the second row and the third row are arranged between two welding points of the first row arranged in the orthogonal direction, and the second row and the third row The welding points in a row are arranged so as to divide the welding points in the orthogonal direction of the first row into three equal parts,
At least the non-skin contact surface side non-woven fabric of the two non-woven fabrics is a 85% 60% less transparency and 10 g / ^{m 2} or more 20 g / ^{m 2} or less of the mass per unit area,
A pants-type absorbent article, wherein the stretchable film has a brightness of 70% or less and a basis weight of 20 g / m ² or more and 40 g / m ² or less.

Images