JP7382239B2 - Pants-type absorbent article - Google Patents

Description

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

As shown in FIG. 6, the conventional pants-type absorbent article 100 is designed to be easy to wear and to achieve a good fit while being worn. A large area of gathers 110 in which an elastic member such as a rubber thread is arranged is provided, and this is one of the external features.

Patent Document 1 includes an absorbent body and an exterior body that supports the absorbent body, and the exterior body is composed of a ventral part, a dorsal part, and a crotch part interposed between these parts, The welded area between the side edge of the side edge and the side edge of the dorsal side part, which forms the waist opening and the leg opening, and approximately the entire circumference of each peripheral edge of the waist opening and the leg opening. Disclosed is a pants-type absorbent article, including an elastic stretchable member disposed across the belt and forming continuous gathers, the welded joint having a non-welded part with a length of 1 cm or more at approximately the center of the welded joint. ing. The pants-type absorbent article is described as having good fit while maintaining a good wearing feeling and feel.

However, the above-mentioned continuous gathers characterize the appearance of pants-type absorbent articles such as disposable diapers, and bring about a large difference in appearance from underwear made of cloth or the like. The rubber thread that is visible through the gathers, particularly around the abdomen and buttocks, and the many large wrinkles around these areas do not exist in cloth underwear. For wearers who do not want third parties to know that they are using a pants-type absorbent article, such a difference in appearance is not desirable, and a pants-type absorbent article that has an appearance more similar to cloth underwear is desired. .

In order to improve the appearance problems of pants-type absorbent articles, a composite sheet, which is a laminate of a nonwoven fabric as a surface material and a stretchable film, has been proposed as an exterior body. Patent Document 2 discloses a breathable stretch film containing one or more polymers selected from polyurethane, polyetheramide, and polyester elastomer, and a breathable stretch film that is bonded to the stretch film in two orthogonal directions. Techniques are disclosed for using composite sheets, which are biaxially elastically stretchable breathable laminates comprising a stretchable spunbond nonwoven fabric, in the outer packaging of diapers and personal care products.

Japanese Patent Application Publication No. 10-137287 Japanese Patent Application Publication No. 2008-279774

However, when a conventional composite sheet is used as an exterior body and the entire surface of the absorber is fixed to the elastic sheet according to a conventional method, an elastic film is formed at the fixed part between the absorbent body and the composite sheet (hereinafter also simply referred to as the "fixed part"). This prevents breathability, so it tends to get stuffy when worn. In addition, the adhered portions become hard and the feel of the pants-type absorbent article as a whole deteriorates. In addition, in order to improve breathability, instead of fixing the entire surface of the absorber, it is possible to scatter small areas of fixed parts to increase the number of fixed parts per unit area, but even in that case, The problem of the exterior body becoming hard to the touch is not fully resolved.

An object of the present invention is to provide a pants-type absorbent article that uses a composite sheet, which is a laminate of a nonwoven fabric and a stretchable film, as an exterior body and has excellent stretchability, breathability, and feel when worn. .

As a result of extensive research to solve the above problems, the present inventors have found that (a) in a composite sheet, a nonwoven fabric and a stretchable film are integrated by a plurality of adhesive parts interposed between them and spaced apart from each other; (b) By forming the adhesive part into a predetermined planar shape, a composite sheet having a predetermined ventilation resistance value can be obtained; and (b) By using the composite sheet as an exterior body, a desired pants-type absorbency can be obtained. The inventors have discovered that an article can be obtained, and have completed the present invention.
The present invention provides, as preferred embodiments, pants-type absorbent articles as described in (1) to (5) below, for example.

(1) An absorbent main body including a liquid-permeable top sheet, a liquid-impermeable back sheet, and an absorbent body disposed between the top sheet and the back sheet; A pants-type absorbent article comprising: an exterior body divided into a side part, a crotch area, and a back part, wherein the ventral part and the back part are arranged between a plurality of nonwoven fabrics and the nonwoven fabric. and a plurality of adhesive parts spaced apart from each other in the plane direction to integrate the nonwoven fabric and the stretchable film; The ventilation resistance value when stretched is in the range of 0.01 kPa·s/m or more and 0.5 kPa·s/m or less, and each of the bonded parts has a corner derived from a square and a partially circular arc wire derived from a circle. A pants-type absorbent article having a planar shape in which and are connected.
(2) The pants-type absorbent according to (1) above, wherein each of the adhesive portions has a planar shape in which the plurality of corner portions originating from a quadrangle and the plurality of partial arc lines originating from a circle are connected. Goods.
(3) The pants-type absorbent article according to (1) or (2) above, wherein the composite sheet is an integrated product including the adhesive portion formed by heat fusion bonding and/or ultrasonic bonding.
(4) The pants-type absorbent article according to any one of (1) to (3) above, wherein the composite sheet has an elongation rate in the stretching direction of 150% or more and 270% or less.
(5) The pants-type absorbent article according to any one of (1) to (4) above, further comprising an elastic stretchable member disposed extending from the abdominal part to the back part via the crotch part.

According to the present invention, there is provided a pants-type absorbent article that uses a composite sheet, which is a laminate of a nonwoven fabric and a stretchable film, as an exterior body and has excellent stretchability, breathability, and feel when worn.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view schematically showing the appearance of a pants-type absorbent article according to a first embodiment of the present invention. FIG. 2 is a schematic development view of the pants-type absorbent article shown in FIG. 1. FIG. 3 is a schematic cross-sectional view in the width direction taken along the X ₁ -X ₁ section line in FIG. 2. FIG. It is a schematic plan view which expands and shows an example of each embodiment of an adhesive part and its arrangement pattern. FIG. 1 is a schematic diagram showing an embodiment of a manufacturing example of a composite sheet. FIG. 1 is a schematic diagram showing the appearance of a conventional pants-type absorbent article.

The pants-type absorbent article 1 according to the first embodiment will be described below with reference to the drawings. Wearing the pants-type absorbent article 1 refers to a state in which the pants-type absorbent article 1 is worn on the body, regardless of whether before, during, or after absorbing bodily fluids. In this specification, the longitudinal direction is a direction extending from the front and back of the wearer when wearing the pants-type absorbent article 1, the width direction is a direction perpendicular to the longitudinal direction, and the thickness direction is a longitudinal direction. and a direction substantially perpendicular to a plane including the width direction. When the pants-type absorbent article 1 is worn on the body, the surface that contacts or faces the wearer's skin is called the skin side, and the surface that contacts or faces the wearer's clothing is called the non-skin side. , and so on. In addition, body fluids refer to fluids discharged from the body, such as urine, blood, and water in loose stools.

<Pants-type absorbent article>
FIG. 1 is an external perspective view of the pants-type absorbent article 1, FIG. 2 is a schematic developed plan view of the pants-type absorbent article 1, and FIG. 3 is a cross-sectional view of the pants-type absorbent article 1 in the width direction. . Each figure does not define the dimensions of each component of the pants-type absorbent article 1, such as the exterior body 10 and the absorbent main body 20, or the size relationship thereof. The dimensions of each component can be appropriately selected from a wide range depending on the purpose of the pants-type absorbent article 1, the age of the wearer, and the like. In FIG. 3, the constituent members are stacked with no gaps, but this embodiment also includes embodiments in which at least one gap exists between at least one layer.

As shown in FIGS. 1 to 3, the pants-type absorbent article 1 of the present embodiment includes an exterior body 10 that constitutes its external shape, and is supported in a predetermined area of the exterior body 10, and extends from the front and back of the wearer's groin area. and an absorbent main body 20 having a substantially band-like shape in the front-rear direction and covering the absorbent main body 20 from the front to the back. The exterior body 10 has a ventral part 11 that mainly contacts the wearer's abdomen, a dorsal part 12 that mainly contacts the wearer's back, and is located between the ventral part 11 and the dorsal part 12. The crotch area 13 mainly contacts the wearer's crotch area. The exterior body 10 mainly supports the absorbent body 20 on the skin side of the crotch area 13, and is arranged so that part or all of the absorbent body 20 overlaps the crotch area 13. The absorbent body 20 absorbs and retains the wearer's body fluids.

It is preferable that the longitudinal dimension of the pants-type absorbent article 1 before disposing the elastic elastic member 1 when unfolded is 600 mm or more and 1000 mm or less, and the width direction dimension is 450 mm or more and 900 mm or less. By setting the unfolded dimensions of the pants-type absorbent article 1 before disposing the elastic elastic member within the above range, the pants-type absorbent article for adults of various sizes such as S size, M size, L size, etc. can be provided. The pants-type absorbent article 1 can be used, for example, as a paper diaper, a sanitary napkin, a disposable diaper for incontinence, or the like.
Hereinafter, each component of the pants-type absorbent article 1 of this embodiment will be explained in more detail in the order of the absorbent main body 20 and the exterior body 10.

(absorbent body)
The absorbent main body 20 of the present embodiment includes a liquid-permeable top sheet 21 disposed relatively on the skin side, and a liquid-impermeable top sheet 21 disposed relatively on the non-skin side opposite to the top sheet 21. The absorbent body 23 is arranged between the top sheet 21 and the back sheet 22, and the three-dimensional gathers 24 are included. It has a unique structure. The absorbent main body 20 is arranged mainly on the skin side of the crotch region 13 of the exterior body 10 so as to extend from the ventral region 11 to the dorsal region 12. The absorbent main body 20 is fixed to the exterior body 10 using an adhesive such as hot melt, thermal fusion, ultrasonic bonding, or the like.

The base material of the top sheet 21 of this embodiment only needs to have liquid permeability that allows bodily fluids to move to the absorbent body 23. For example, the base material of the top sheet 21 may be a nonwoven fabric such as a thermal bond nonwoven fabric, or a laminated layer of thermal bond/spunbond. Examples include composite nonwoven fabrics, open films such as open polyethylene films, foamed films such as polyethylene foam and urethane foam, and multilayer sheets obtained by laminating two or more of these. Further, the top sheet 21 is preferably subjected to embossing or perforation on the surface in order to improve liquid permeability. As for the processing method, any known method can be used without any limitation. Further, in order to reduce irritation to the skin, it is also preferable for the top sheet 21 to contain a lotion, an antioxidant, an anti-inflammatory component, a pH adjuster, an antibacterial agent, a humectant, and the like. Furthermore, from the viewpoint of strength and workability, the basis weight of the top sheet 21 is preferably 14 g/m ² or more and 40 g/m ² or less. The shape of the top sheet 21 is not particularly limited, but may be any shape as long as it covers the absorbent body 23 in order to guide liquid such as urine to the absorbent body 23.

The base material of the backsheet 22 of this embodiment may be any material having liquid impermeability that prevents leakage of body fluids held by the absorber 23, and may be a nonwoven fabric, a resin film, or a laminated layer of two or more of these. Examples include multilayer sheets. The manufacturing method of the nonwoven fabric is not particularly limited, and examples include spunbond nonwoven fabric, meltblown nonwoven fabric, spunbond nonwoven fabric/meltblown nonwoven fabric laminate, spunbond nonwoven fabric/meltblown nonwoven fabric/spunbond nonwoven fabric laminate, and the like. Examples of the resin film include polyester film, polyvinyl alcohol film, polyethylene film, polypropylene film, and composite film of polyethylene and polypropylene. Further, in order to prevent stuffiness when worn, the back sheet 22 preferably has moisture permeability. Examples of methods for imparting moisture permeability include adding a filler to the base resin film and embossing the backsheet 22 for perforation.

The base material of the absorbent body 23 of this embodiment is not particularly limited as long as it is generally used for absorbent articles such as sanitary napkins, diapers, and urine pads. For example, fluff pulp, super absorbent resin (Super It is formed from a material such as Absorbent Polymer (hereinafter also referred to as "SAP") or a hydrophilic sheet. Examples of fluff pulp include those obtained by defibrating wood pulp and non-wood pulp such as synthetic fibers and polymer fibers into fluff. Further, examples of the super absorbent resin include sodium polyacrylate, and examples of the hydrophilic sheet include tissue, absorbent paper, and hydrophilic nonwoven fabric.

The absorbent body 23 is constructed in the form of a single-layer or multi-layer sheet using the above-mentioned base material. Among these, those formed by mixing a hydrophilic fiber matrix of a web of fluff pulp, such as wood pulp fluff, with SAP particles are preferred. Further, in order to prevent leakage of SAP particles and to stabilize the shape of the absorber 23, it is preferable to wrap the absorber 23 in a hydrophilic sheet (not shown) such as tissue. Furthermore, embossing the surface of the absorbent body 23 is preferable because it controls the diffusion of body fluids and allows the absorbent body 23 to easily deform according to the user's body shape.

The three-dimensional gathers 24 are provided, for example, to prevent side leakage of body fluids. In the three-dimensional gathers 24 of this embodiment, one end in the width direction is fixed along the longitudinal direction near both ends in the width direction of the skin side of the back sheet 22, and a middle part in the width direction is fixed near both ends in the width direction of the skin side of the top sheet 21. A three-dimensional gather sheet 24b that is fixed along the longitudinal direction and whose other end in the width direction is a free end; It includes an elastic elastic member 24a for three-dimensional gathers that imparts elasticity. The other end in the width direction, which has the ability to stand up, is stretchable and deformable according to the wearer's body shape.

For the three-dimensional gather sheet 24b, for example, various nonwoven fabrics can be used without limitation, and for the three-dimensional gather elastic elastic member 24a, a general elastic elastic member such as thread rubber can be used without particular limitation. Note that one widthwise end (fixed end) of the three-dimensional gathered sheet 24b joins the periphery of the top sheet 21 and the periphery of the backsheet 22 near both widthwise ends of the skin side of the backsheet 22, and encloses the absorbent body 23. It may be fixed along the longitudinal direction near both widthwise ends of the bag, near both widthwise ends of the skin side of the top sheet 21, or near both widthwise ends of the non-skin side of the backsheet 22. The absorbent main body 20 of this embodiment also includes an embodiment that does not include the three-dimensional gathers 24.

<Exterior body>
The exterior body 10 includes a ventral part 11 that mainly contacts the wearer's ventral side, a dorsal part 12 that mainly contacts the wearer's dorsal side, and a space between the ventral part 11 and the dorsal part 12. The absorbent main body 20 is supported mainly on the skin side of the crotch area 13, and has a crotch area 13 interposed therebetween and mainly in contact with the wearer's crotch area. Furthermore, as shown in FIGS. 2 and 3, the exterior body 10 of the present embodiment has a pair of left and right leg gathers that extend from the ventral side part 11 to the crotch area 13 and to the dorsal side part 12 along the widthwise end. It is equipped with 16.

(composite sheet)
A composite sheet 17 is used for the ventral side part 11 and the dorsal side part 12. By using the composite sheet 17, the appearance of the pants-type absorbent article 1 can be made closer to the appearance of, for example, cloth underwear by reducing the gathers on the surface. In particular, if there are many gathers 110 on the surface as shown in FIG. 6, even if you put on a jacket, the shape of the gathers 110 will appear on the surface of the jacket, making it difficult for others to recognize that you are wearing the pants-type absorbent article 100. There is a risk of In contrast, in this embodiment, as shown in FIG. 1, by using the composite sheet 17, the amount of surface gathers can be greatly reduced. Therefore, the possibility that others will recognize that you are wearing the pants-type absorbent article 1 is greatly reduced. Furthermore, since the composite sheet 17 disposed on the ventral side part 11 and the dorsal side part 12 has good breathability, the pants-type absorbent article 1 itself has good breathability, even when worn for a long time. It is extremely difficult to get stuffy and provides a good wearing feeling.

The composite sheet 17 of the present embodiment includes two nonwoven fabrics 14, a stretchable film 15 interposed between the two nonwoven fabrics 14, and a stretchable film 15 interposed between the nonwoven fabric 14 and the stretchable film 15, which are mutually interposed in the plane direction. A plurality of adhesive parts 30 are provided which are spaced apart and which integrate the nonwoven fabric 14 and the stretchable film 15. The bonded portion 30 is a portion where the nonwoven fabric 14 and the stretchable film 15 are bonded. In this specification, the integration of the nonwoven fabric 14 and the stretchable film 15 means that the nonwoven fabric 14 and the stretchable film 15 adhere to each other, and this adhesion is maintained at least until the expiration date of the pants-type absorbent article 1. means. The adhesive portion 30 has a predetermined planar shape, which will be described later. Further, it is preferable to use a method such as heat fusion bonding or ultrasonic bonding to integrate the nonwoven fabric 14 and the stretchable film 15. By using these integration methods, the adhesive portion 30 having a predetermined planar shape can be easily formed. The integration method will also be described later. On the other hand, the crotch portion 13 may be made of the same composite sheet 17 as the abdominal part 11 and the back part 12, or may be made of a nonwoven fabric as in the past. Further, when a nonwoven fabric is used as the exterior body of the crotch portion 13, it is preferable to use a laminate of two or more layers of nonwoven fabrics as in the case of conventional exterior bodies. Further, the type of nonwoven fabric is not particularly limited, and can be selected from, for example, the same type of nonwoven fabric 14 described later.

The composite sheet 17 of this embodiment is an integrated product of a laminate of two nonwoven fabrics 14 and one stretchable sheet 15 by an adhesive part 30, but is not limited to this, and is composed of three or more nonwoven fabrics 14 and one stretchable sheet 15. Alternatively, the nonwoven fabrics 14 may be integrated with two or more elastic films 15 disposed between each nonwoven fabric 14 using the adhesive portion 30 of a laminate. The composite sheet 17 may be a layered sheet extending in one direction when viewed in cross section and having a three-dimensional shape having a flat surface, or may be a sheet having a wavy line shape extending in one direction in cross section and having a regular surface. It may also be a sheet having a three-dimensional shape with irregularities. From the viewpoints of texture, touch, cushioning properties, etc., the latter sheet whose cross-sectional view has a wavy line shape extending in one direction is preferable.

The composite sheet 17 has a ventilation resistance value measured after being stretched by 250% in the stretching direction, which is in the range of 0.01 kPa·s/m or more and 0.5 kPa·s/m or less, preferably 0.05 kPa·s/m. The range is from 0.35 kPa·s/m to 0.35 kPa·s/m. Since the composite sheet 17 has a ventilation resistance value within the above range, even if the absorbent main body 20 is attached to the skin side of the crotch area 13, the composite sheet 17 constituting the ventral side part 11 and the dorsal side part 12 has a good performance. Breathability is maintained. If the ventilation resistance value is less than 0.01 kPa·s/m, the heat retention of the pants-type absorbent article 1 tends to decrease, and the feeling of wearing tends to decrease. When the ventilation resistance value exceeds 0.5 kPa·s/m, the breathability of the pants-type absorbent article 1 decreases, and there is a tendency for stuffiness to occur when worn.

The elongation rate of the composite sheet 17 in the stretching direction is preferably 150% or more and 270% or less, more preferably 160% or more and 260% or less. Here, the elongation rate in the stretching direction is the ratio of the length increased by stretching to the natural length in a non-stretched state. The elongation rate can be measured using, for example, an autograph manufactured by Shimadzu Corporation. Since the elongation rate of the composite sheet 17 in the stretching direction is within the above range, the wearer can easily put on and take off the wearer, have appropriate tightness and feel comfortable to wear, and furthermore, the pants type is less prone to slipping down and provides a sense of security. Absorbent article 1 is obtained.

The composite sheet 17 has a tensile load of 0.8 N/50 mm or more and 2.0 N/50 mm or less when stretched 120% in the stretching direction, and 2.0 N/50 mm when stretched 150% in the stretching direction. It has an elongation load of 50 mm or more and 3.5 N/50 mm or less. Note that since the elongation rate varies depending on the wearer's body shape, elongation loads of 120% and 150% were specified. By doing this, there will be no difference in fit depending on body type. Further, the composite sheet 17 has an elongation rate in the stretching direction of 200% or more and 270% or less. Therefore, since it is possible to stretch 200% or more compared to conventional products, it is possible to provide a pants-type absorbent article 1 that is easy for the wearer to put on and take off. Here, the elongation rate in the stretching direction is the ratio of the increased length due to stretching to the natural length in the non-stretched state, as in the case of 120% stretching in the stretching direction. The extension load can be measured using, for example, an autograph manufactured by Shimadzu Corporation.

Moreover, it is preferable that the composite sheet 17 has a breaking elongation of 210% or more and 280% or less in the stretching direction. The elongation at break is defined as the elongation at break, where L1 is the length of the composite sheet 17 at its natural length in a non-stretchable state, and L2 is the length when the composite sheet 17 is stretched in the stretching direction and broken. (L2/L1)×100(%). Having a breaking elongation within this range has the effect that the pants will not be stretched or torn easily even if the pants are opened wide when putting on and taking off. The elongation at break can be measured using, for example, an autograph manufactured by Shimadzu Corporation.

As the nonwoven fabric 14 constituting the composite sheet 17 of this embodiment, any nonwoven fabric conventionally used for the exterior of pants-type absorbent articles can be used, such as thermal bond nonwoven fabric, air-through nonwoven fabric, spunbond nonwoven fabric, and the like. Examples include a laminate of two or more types. Two or more types of laminates are joined by, for example, hot melt adhesive, thermal welding, ultrasonic welding, or the like. It is preferable that the nonwoven fabric 14 contains fibers made of thermoplastic resin such as polyester, polypropylene, and polyethylene as constituent fibers. When the composite sheet 10 includes a plurality of nonwoven fabrics 14, the nonwoven fabrics 14 may be of different types or of the same type. In addition, from the viewpoint of obtaining a composite sheet 17 having a predetermined ventilation resistance value and elongation rate in the stretching direction, the basis weight of the nonwoven fabric 14 is preferably 15 g/m ² or more and 40 g/m ² or less, more preferably 18 g/m ² or more. It is 40g/ ^m2 or less.

The stretchable film 15 constituting the composite sheet 17 of the present embodiment is included in the composite sheet 17 in a state where it is stretched in the stretching direction (the elongation rate in the stretching direction is within a predetermined range). The stretchable sheet is not particularly limited as long as it has stretchability, but a film made of a synthetic resin that exhibits stretchability when formed into a film is preferred. Examples of the synthetic resin include polyester elastomers, polyolefin elastomers, polyurethane resins, polyamide resins, and alloys of two or more of these. Among these, from the viewpoint of cost and elasticity, a film containing a polyurethane resin is preferred, and a film made of a polyurethane resin is more preferred. From the viewpoint of obtaining a composite sheet 17 having a predetermined ventilation resistance value and elongation rate in the stretching direction, the thickness of the stretchable film 15 is preferably 8 μm or more and 40 μm or less, and the stretch rate of the stretchable film 15 in the stretching direction is preferably It is 100% or more and 350% or less.

FIG. 4 is an enlarged schematic plan view showing an example of the planar shape and arrangement pattern of the adhesive portions 30 on the surface of the composite sheet 17. As shown in FIG. As shown in FIG. 4, the composite sheet 17 is integrated by a plurality of adhesive parts 30, which has a planar shape that is a combination of a square and a circle in plan view. The adhesive portion 30 has a planar shape in which a corner derived from a quadrilateral and a partial arc line derived from a circle are connected, and preferably a plurality of corner portions derived from a quadrilateral and a plurality of corner portions derived from a circle are connected. has a planar shape in which the partial circular arc lines are connected.

The adhesive portion 30 of this embodiment has a shape in which a rectangle 40 extending perpendicularly to the stretching direction Y of the composite sheet 17 and a circle 41 are integrated, and the intersection of the diagonal lines of the rectangle 40 and the center of the circle 41 coincide (overlap), and the diameter of the circle 41 is longer than the short side of the rectangle 40 and shorter than the long side. The adhesive part 30 of this embodiment has four corners derived from a rectangle 40 and two partial arc lines derived from a circle 41, one of which is in one direction of the expansion/contraction direction Y and the other is protrude in the other direction of expansion and contraction. In the adhesive part 30 of this embodiment, the rectangular portion 40 extends in a direction substantially perpendicular to the stretching direction Y, but the present invention is not limited to this. It may be tilted at any angle such as 0.degree., 45.degree., 60.degree., or 90.degree. Hereinafter, the inclination of the rectangular portion 40 with respect to the expansion/contraction direction will also be simply referred to as "inclination Z." Such adhesive parts 30 are arranged in a pattern X and/or a pattern Y along the stretching direction Y of the composite sheet 17. A predetermined phase difference may be provided for each column in pattern X or Y. Further, the adhesive portions 30 may be arranged in a grid pattern, a grid pattern, or the like.

The composite sheet 17, which is integrated with a plurality of adhesive parts 30 having such a planar shape, has appropriate mechanical strength, elasticity, and tightening properties, so it is easy to form gathers by disposing elastic elastic members. It is very suitable as the exterior body of the pants-type absorbent article 1 because it does not require the composite sheet and the low air permeability, which is a drawback of conventional composite sheets, has been improved.

In FIG. 4, a preferable example of each dimension of the adhesive part 30 is shown. The dimension (length in the stretching direction) of the rectangular 40 part of the adhesive part 30 indicated by the symbol "A" is 250% stretched in the stretching direction Y. Sometimes it is 0.2 mm or more and 0.4 mm or less, and the dimension in the direction substantially perpendicular to the expansion/contraction direction Y of the adhesive part 30, indicated by the symbol "B", is 0.8 mm or more and 2.0 mm or less, and the dimension is indicated by the symbol "B". The diameter of the circular portion 41 of the bonded part 30, indicated by "C", is 0.3 mm or more and 0.8 mm or less, and the shortest length of the bonded part 30 adjacent to each other in the expansion/contraction direction Y, indicated by the symbol "D ₁ " is 1.0 mm or more and 3.0 mm or less when the composite sheet 17 is stretched by 250% in the stretching direction Y, and is denoted by the symbol “D ₂ ” and is an adhesive bond that is adjacent to each other in a direction substantially perpendicular to the stretching direction Y. The shortest length of the parts 30 is 1.0 mm or more and 3.0 mm or less, and the shortest length of the adhesive parts 30 adjacent to each other in the stretching direction Y in the arrangement Y, indicated by the symbol "E", is 1.0 mm or more and 3.0 mm or less. When elongated by 250% in direction Y, the length is 2.0 mm or more and 5.0 mm or less. By setting the adhesive portion 30 within the above range, the breathability of the composite sheet 17 is further improved, and the decrease in durability of the stretchable film 15 is alleviated.

In the composite sheet 17, it is preferable that the adhesive area ratio of the adhesive portion 30 is 4% or more and 18% or less. Here, the adhesion area ratio is the ratio of the total area of the adhesive portions 30 present in the unit area of the composite sheet 17, expressed as a percentage. If the adhesion area ratio is less than 4%, the air permeability of the composite sheet 17 tends to decrease. On the other hand, when the adhesive area ratio exceeds 18%, the strength of the composite sheet 17 tends to decrease.

The composite sheet 17 can be produced, for example, by the manufacturing method shown in FIG. FIG. 5 is a drawing schematically showing a method for manufacturing the composite sheet 17. As shown in FIG. FIG. 5(a) is a schematic side view showing all steps of the method for manufacturing the composite sheet 17. FIG. 5(b) is an enlarged schematic cross-sectional view showing the third step (bonding step). The manufacturing method shown in FIG. 5 is a method using ultrasonic bonding or thermal fusion, and includes first to third steps in this order.

In the first step, the elastic film 15 wound around the feeding roller 51 is transported while applying a predetermined tension. The stretchable film 15 is transported while being stretched in the transport direction with a predetermined tension. The predetermined tension is a tension that stretches the stretchable film 15 by 200% or more, more preferably by 250±30%.

In the second step following the first step, the respective nonwoven fabrics 14 wound around the two feeding rollers 52 are laminated on top and bottom of the stretchable film 15 that is conveyed in a stretched state to obtain a laminate before integration.

In the third step following the second step, the pre-integrated laminate is passed through the pressure contact portion (hereinafter also referred to as "nip section") of the first and second bonding rollers 53 and 54 to form a predetermined bonded portion 30. A composite sheet 17 is obtained. The first bonding roller 53 is provided with a plurality of recesses 55 extending in the width direction and having predetermined dimensions and a predetermined internal space shape at predetermined intervals in the circumferential direction on the circumferential surface of the first joining roller 53 . The second bonding roller 54 has a convex portion on its peripheral surface that extends in the width direction and has a predetermined size and a predetermined three-dimensional shape (a three-dimensional shape that allows the tip portion to be inserted into the recess 55 with the interposition of the laminate). A plurality of 56 are provided at predetermined intervals in the circumferential direction. The first and second bonding rollers 53 and 54 are engaged with each other so that the tip of the convex portion 56 can be inserted into the concave portion 55, and are pressed together with a predetermined pressure. In the nip portion of the first and second bonding rollers 53 and 54, seal lines that are substantially continuous in the width direction of the roller circumferential surface are formed at intervals of 0.5 mm or more and 2.0 mm or less in the expansion and contraction direction. There is. Either or both of the first and second bonding rollers 53 and 54 are equipped with an ultrasonic generator or a heating device, and can apply ultrasonic waves to the inner wall surface of the recess 55 or at least the tip portion of the convex portion 56. Or it is configured to be heated.

In the third step, the laminate obtained in the second step is passed through the nip portion of the first and second bonding rollers 53 and 54 under pressure, so that the inner wall surface of the recess 55 and the tip portion of the convex portion 56 are bonded. By applying ultrasonic waves or heating the seal wire that is the contact point, a plurality of adhesive parts 30 having a predetermined planar shape are formed, and the nonwoven fabric 14 and the stretchable film 15 are integrated by the plurality of adhesive parts 30, A composite sheet 17 with few surface wrinkles and smooth texture is obtained. That is, a plurality of adhesive parts 30 having the planar shape shown in FIG. 4 are formed at predetermined intervals shown in FIG. 4. A composite sheet 17 in which the nonwoven fabric 14 and the stretchable film 15 are integrated is obtained.

(leg gathers)
As shown in FIGS. 2 and 3, the leg gathers 16 includes an elastic elastic member 16a and a leg gathers sheet 16b. The elastic stretchable member 16a is not particularly limited, and for example, a rubber thread or the like can be used. As the leg gather sheet 16b, for example, various nonwoven fabrics can be used. By providing the leg gathers 16, it becomes possible to expand and contract not only the direction of expansion and contraction (width direction) but also the direction that intersects the direction of expansion and contraction (longitudinal direction), improving the fit around the crotch area. The shape of the leg gathers 16 does not easily appear on the surface of clothing when the pants-type absorbent article 1 is worn.

<Method for manufacturing pants-type absorbent article>
The pants-type absorbent article 1 is a conventional pants-type absorbent article, except that the composite sheet 17 is used as the exterior body 10 of the ventral part 11 and the dorsal part 12, or the ventral part 11, the dorsal part 12, and the crotch part 13. It can be produced in the same way as sex products. For example, the ventral part 11 and the dorsal part 12 are made of the composite sheet 17, the crotch part 13 is made of a conventional nonwoven fabric laminate, and these parts are joined in the longitudinal direction in a predetermined order to obtain the exterior body 10. A process of fixing the absorbent body 20 to a predetermined position (mainly the crotch area 13) on the skin side of the exterior body 10, and a process of fixing the absorbent body 20 to a predetermined position (mainly the crotch area 13) on the skin side of the exterior body 10, and fixing leg gathers 16 near both widthwise ends of the absorbent body 20 on the skin side of the exterior body 10. Pants-type absorbent article 1 is obtained by the manufacturing method including the step of arranging. The pants-type absorbent article 1 thus obtained is manufactured into a product by folding and bagging in a predetermined order.

Although the present invention has been described above using the embodiments, it goes without saying that the technical scope of the present invention is not limited to the scope described in the above embodiments. It will be apparent to those skilled in the art that various changes or improvements can be made to the embodiments described above. Furthermore, it is clear from the claims that such modifications or improvements may be included within the technical scope of the present invention.

Hereinafter, the present invention will be described in detail by giving examples. Note that the present invention is not limited to the examples shown below.

<Examples 1 to 3, Comparative Examples 1 to 3>
A disposable diaper was produced as a pants-type absorbent article.
The exterior body of the ventral part, dorsal part, and crotch part has the planar shape and arrangement shown in FIG. 4 (array X and arrangement Y are arranged alternately in the direction perpendicular to the rows), and 1 (dimensions A, B, C, D ₁ , D ₂ , and E shown in FIG. 4), and each bonded part of Examples 1 to 3 formed by ultrasonic bonding, 2 A composite sheet was used in which a polyurethane film (thickness: 20 μm, expansion/contraction ratio in the expansion/contraction direction: 250%) was placed between sheets of polypropylene spunbond nonwoven fabric (basis weight: 20 g/m ² ) and integrated. In Comparative Examples 1 to 3, composite sheets were produced in the same manner as in Examples 1 to 3, except that the planar shape of the bonded portion was circular (Comparative Example 1) or rectangular (Comparative Examples 2 and 3).

In addition, an air-through nonwoven fabric with a basis weight of 30 g/m ² is used as the top sheet, a breathable polyethylene film with a basis weight of 32 g/m ² is used as the back sheet, and 12 g of fluff pulp, polyacrylic acid-based An absorbent body made of a mixture of 11 g of a water-absorbing polymer made of resin was arranged to prepare an absorbent body, and the body was bonded to the skin side of the outer body mainly in the crotch area using a hot melt adhesive. In addition, two 940 decitex urethane rubber thread rubber stretched in the longitudinal direction of spunbond nonwoven fabric are placed on the skin sides of the exterior body at both ends of the absorbent body in the width direction, each stretched to 000%. The gathers were joined to produce a pants-type absorbent article.

Measurement test pieces obtained by cutting out the ventral parts from each of the pants-type absorbent articles of Examples 1 to 3 and Comparative Examples 1 to 3 were subjected to a "One Shot 3D Measurement Macroscope VR-3100" manufactured by Keyence Corporation. A photograph was taken with the non-skin side surface stretched to 250%, and each dimension of the adhesive portion (dimensions A, B, C, D ₁ , D ₂ , and E shown in FIG. 4) was measured. The results are shown in Table 1.

The following evaluation tests and sensory evaluations were conducted for each of the pants-type absorbent articles of Examples 1 to 3 and Comparative Examples 1 to 3. The results are shown in Table 1.

(Breathability evaluation, extensibility evaluation)
Measurement test pieces obtained by cutting out the ventral part from each of the pants-type absorbent articles of Examples 1 to 3 and Comparative Examples 1 to 3 were stretched once by 250% in the stretching direction, and then released from stretching. The ventilation resistance value R (kPa·s/m) was measured using "Air Permeability Tester KES-F8" manufactured by Co., Ltd. Further, using an autograph manufactured by Shimadzu Corporation, the elongation load (N/50 mm) at 120% elongation and 150% elongation with a sample width of 50 mm (direction perpendicular to the drawing direction) was measured.

(Evaluation of elasticity, fit, and flexibility of the exterior body part)
Each of the pants-type absorbent articles of Examples 1 to 3 and Comparative Examples 1 to 3 was worn by 20 monitors, and the elasticity (whether it is easy to wear or not), fit, and flexibility of the outer body part was evaluated. A sensory evaluation was conducted regarding whether or not the product had a soft touch and texture. Regarding the sensory evaluation, both evaluations were conducted using two options, ``good'' and ``bad,'' and evaluated based on the following criteria.
〇: When 12 to 20 people have rated “Good” △: When 5 to 11 people have rated “Good” ×: When there is no “Good” or 1 to 4 people have rated “Good”

1 Pants-type absorbent article 10 Exterior body 11 Ventral part 12 Dorsal part 13 Crotch part 14 Non-woven fabric 15 Stretch film 16 Leg gathers 17 Composite sheet 20 Absorbent main body 21 Top sheet 22 Back sheet 23 Absorbent body 24 Three-dimensional gathers

Claims (4)

an absorbent body including a liquid-permeable top sheet, a liquid-impermeable back sheet, and an absorbent body disposed between the top sheet and the back sheet; an abdominal portion supporting the absorbent body; A pants-type absorbent article comprising: an exterior body divided into a crotch area and a backside area;
The ventral side portion and the dorsal side portion include a plurality of nonwoven fabrics, a stretchable film disposed between the nonwoven fabrics, and a plurality of nonwoven fabrics and a stretchable film that are spaced apart from each other in the surface direction and integrate the nonwoven fabric and the stretchable film. a composite sheet including an adhesive part;
The nonwoven fabric is a thermal bond nonwoven fabric, an air-through nonwoven fabric, a spunbond nonwoven fabric, or a laminate of two or more of these,
The basis weight of the nonwoven fabric is 15 g/m ² or more and 40 g/m ² or less,
The stretchable film is a polyester elastomer, a polyolefin elastomer, a polyurethane resin, a polyamide resin, or an alloy of two or more of these,
The thickness of the stretchable film is 8 μm or more and 40 μm or less,
The elongation rate of the stretchable film in the stretching direction is 100% or more and 350% or less,
The planar shape of each of the adhesive parts is such that a rectangle extending perpendicularly to the direction of expansion and contraction of the composite sheet overlaps a circle whose center coincides with the intersection of diagonals of the rectangle, and the diameter of the circle is equal to the short length of the rectangle. longer than the side and shorter than the long side,
The dimensions of the adhesive part are such that when the composite sheet is stretched by 250% in the stretching direction, the length of the rectangle in the stretching direction is 0.2 mm or more and 0.4 mm or less, and the length of the long side of the rectangle is 0.2 mm or more and 0.4 mm or less. The diameter of the circle is 0.8 mm or more and 2.0 mm or less, and the diameter of the circle is 0.3 mm or more and 0.8 mm or less, and the bonded portions are adjacent to each other in the stretching direction when the composite sheet is stretched by 250% in the stretching direction. The shortest length of is 1.0 mm or more and 5.0 mm or less, and the shortest length of the bonded parts adjacent to each other in the direction perpendicular to the expansion and contraction direction is 1.0 mm or more and 3.0 mm or less,
The adhesive area ratio of the adhesive part is 4% or more and 18% or less,
The composite sheet is a pants-type absorbent article, wherein the composite sheet has a ventilation resistance value in the range of 0.01 kPa·s/m or more and 0.5 kPa·s/m or less when stretched by 250% in the stretching direction. The pants-type absorbent article according to claim 1 , wherein the composite sheet is an integrated product including the adhesive portion formed by thermal fusion bonding and/or ultrasonic bonding. The pants-type absorbent article according to claim 1 or 2 , wherein the composite sheet has an elongation rate in the stretching direction of 150% or more and 270% or less. The pants-type absorbent article according to any one of claims 1 to 3 , further comprising an elastic stretchable member disposed extending from the abdominal part to the back part via the crotch part.