JP2021118829A - Underpants type absorbent article - Google Patents

Abstract

To provide an underpants type absorbent article using a composite sheet being a laminate of a nonwoven fabric and a flexible film, as an exterior body, and being excellent in flexibility, air permeability, and touch feeling in wearing.SOLUTION: An underpants type absorbent article 1 comprises an exterior body 10 and an absorbent body 20, each of a ventral part 11 and a back part 12 of the exterior body 10 includes a composite sheet 17 comprising: a plurality of nonwoven fabrics 14; a flexible film 15 arranged therebetween; and a plurality of adhesion parts 30 which are arranged in a separated state in a plane direction for integrating the nonwoven fabrics and the flexible film. Each adhesion part 30 comprises a plane shape in which corner parts derived from a square and partial arc lines derived from a circle are coupled. The absorbent body 20 comprises: a liquid permeable top sheet 21; an open film 18 comprising a plurality of funnel shaped open holes; an absorber 23 which includes as absorbent components, a fiber assembly formed of a cellulose acetate tow and a high absorbent polymer carried by the fiber assembly formed of the cellulose acetate tow; and a liquid impermeable back sheet 22, in the order.SELECTED DRAWING: Figure 3

Description

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

As shown in FIG. 7, the conventional pants-type absorbent article 100 is easy to wear and is placed around the waist opening, the leg opening, the waist, etc. in order to realize a good fit during wearing. A gather 110 on which an elastic elastic member such as a rubber thread is arranged is provided in a large area, and this is one of the external features.

Patent Document 1 includes an absorber and an exterior body that supports the absorber, and the exterior body is composed of a ventral side portion, a dorsal side portion, and a crotch portion interposed between them, and is a ventral side portion. It is a welding region between the side edge portion of the waist portion and the side edge portion of the dorsal side portion, and the welded joint portion forming the waist opening and the leg opening, and substantially the entire circumference of each peripheral edge of the waist opening and the leg opening. Disclosed is a pants-type absorbent article comprising an elastic stretchable member which is disposed over and forms continuous gathers, and the welded joint has a non-welded portion having a length of 1 cm or more at a substantially central portion in the width direction thereof. ing. It is described that the pants-type absorbent article has a good fit while maintaining a good fit and texture.

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 gathered part, especially the thread rubber that can be seen through the abdominal area and the buttocks area, and many large wrinkles around the gathered part, are not present in the cloth underwear. For the wearer who does not want the use of the pants-type absorbent article to be known to a third party, such a difference in appearance is not desirable, and a pants-type absorbent article having an appearance closer to that of cloth underwear is desired. ..

In order to improve the appearance problem of the pants-type absorbent article, a composite sheet, which is a laminate of a non-woven fabric as a surface material and an elastic film, has been proposed as an exterior body. Patent Document 2 describes a breathable stretchable film containing one or more polymers selected from polyurethane, polyetheramide, and polyester elastomer, and a stretchable film bonded to the stretchable film in two orthogonal directions. A technique is disclosed in which a composite sheet, which is a biaxially elastic stretchable breathable laminate including a stretchable spunbonded non-woven fabric, is used as an exterior body of a diaper and a personal care product.

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

However, when a conventional composite sheet is used as an exterior body, when the entire surface of the absorber is fixed to the composite sheet according to a conventional method, elasticity is formed in the fixed portion between the absorber and the composite sheet (hereinafter, also simply referred to as "fixed portion"). Since the film impedes breathability, it tends to get stuffy when worn. In addition, the fixed portion becomes hard, and the feel of the pants-type absorbent article as a whole is reduced. Further, in order to improve the air permeability, it is conceivable to increase the number of fixed portions per unit area by interspersing small fixed areas instead of fixing the entire surface of the absorber. The problem that the feel of the exterior body becomes hard is not sufficiently solved.

An object of the present invention is to provide a pants-type absorbent article having excellent elasticity, breathability, and touch when worn, while using a composite sheet which is a laminate of a non-woven fabric and an elastic film as an exterior body. ..

As a result of intensive research to solve the above problems, the present inventors have (a) arranged a predetermined perforated film between the top sheet and the absorber, and used the predetermined fiber aggregate and the absorbent component as the absorbent component. Using an absorbent body containing a highly absorbent polymer, (b) the non-woven fabric and the stretchable film are interposed between them and separated from each other in the plane direction, and integrated by a plurality of adhesive portions having a predetermined planar shape. We have found that a desired pants-type absorbent article can be obtained by using the composite sheet as an exterior body, and have completed the present invention.
The present invention provides, for example, the following pants-type absorbent articles (1) to (7) as a preferred embodiment.

(1) An absorbent body including a liquid-permeable top sheet, a liquid-impermeable back sheet, and an absorber arranged between the top sheet and the back sheet, and an absorbent body that supports the absorbent body and abdomen. A pants-type absorbent article comprising an exterior body divided into a side portion, a lower crotch portion, and a dorsal side portion, wherein the absorbent body is a plurality of fabrics arranged between the top sheet and the absorbent body. The absorber is provided with a perforated film having funnel-shaped pores, and the absorber is a highly absorbent polymer supported on a fiber aggregate composed of cellulose acetate tow and a fiber aggregate composed of the cellulose acetate tow as an absorbent component. Including A pants type having a composite sheet including a plurality of adhesive portions to be integrated, and each of the adhesive portions has a planar shape in which a corner portion derived from a quadrangle and a partial arc line derived from a circle are connected. Absorbent article.
(2) The pants-type absorbent article according to (1) above, wherein the adhesive portion has a planar shape in which a plurality of the corner portions derived from a quadrangle and a plurality of the partial arc lines derived from a circle are connected. ..
(3) The pants-type absorbent article according to (1) or (2) above, wherein the composite sheet is an integrated product including the bonded portion by heat fusion 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 of 150% or more and 270% or less in the expansion and contraction direction.
(5) The weight ratio of the fiber aggregate composed of the cellulose acetate tow to the highly absorbent polymer (weight of the highly absorbent polymer / weight of the fiber aggregate composed of the cellulose acetate tow) is 10% or more and 500% or less. The pants-type absorbent article according to any one of (1) to (4) above.
(6) The perforated film has a perforation diameter of 2 mm or less, a number of perforations of 50 or more / cm ² , and a basis weight of 20 g / m ² or more and 60 g / m ² or less. Any of the pants-type absorbent articles.
(7) The pants-type absorbent article according to any one of (1) to (6) above, further comprising an elastic elastic member arranged from the ventral side to the dorsal side through the crotch part.

According to the present invention, there is provided a pants-type absorbent article having a composite sheet, which is a laminate of a non-woven fabric and an elastic film, as an exterior body, and having excellent elasticity, breathability, and touch when worn.

It is a perspective view which shows typically the appearance of the pants type absorbent article which concerns on 1st Embodiment of this invention. It is a schematic development view of the pants type absorbent article shown in FIG. It is a schematic cross-sectional view in the width direction in the XX'cutting line of FIG. It is a schematic cross-sectional view which shows one Embodiment of a perforated film. It is a schematic plan view which enlarges and shows an example of each embodiment of the adhesive part and the arrangement pattern thereof. It is the schematic which shows one Embodiment of the manufacturing example of a composite sheet. It is a schematic diagram which shows the appearance of the conventional pants type absorbent article.

Hereinafter, the pants-type absorbent article 1 according to the first embodiment will be described with reference to the drawings. As defined herein as follows. Wearing the pants-type absorbent article 1 means a state in which the pants-type absorbent article 1 is worn on the body before, during, and after the absorption of the body fluid. The longitudinal direction is a direction extending in front of and behind the wearer when the pants-type absorbent article 1 is worn, the width direction is a direction orthogonal to the longitudinal direction, and the thickness direction includes the longitudinal direction and the width direction. The direction is approximately perpendicular to one plane. When the pants-type absorbent article 1 is worn on the body, the surface that comes into contact with the wearer's skin or faces the skin is the side of the skin, and the surface that touches the wearer's clothing or faces the clothing is the non-skin side. , And. The body fluid refers to a liquid excreted from the body such as urine, blood, and water in loose stool.

<Pants type absorbent article>
FIG. 1 is an external perspective view of the pants-type absorbent article 1, FIG. 2 is a schematic development plan view of the pants-type absorbent article 1, and FIG. 3 is a width sectional view of the pants-type absorbent article 1. , FIG. 4 is a cross-sectional view of the perforated film 18. Each figure does not define the shape, size, and magnitude relationship of the exterior body 10 and the absorbent main body 20 of the pants-type absorbent article 1 and each of the constituent members included therein. The dimensions of each component can be appropriately selected from a wide range according to the use of the pants-type absorbent article 1, the age of the wearer, and the like. In FIG. 3, each component is laminated without a gap, but the present embodiment also includes an embodiment having at least one gap between at least one layer.

As shown in FIGS. 1 to 4, the pants-type absorbent article 1 of the present embodiment is supported by the outer body 10 constituting the outer shape thereof and a predetermined area of the outer body 10, and the crotch portion of the wearer is moved back and forth. It is provided with an absorbent main body 20 having a substantially band-shaped shape in the front-rear direction covering from the above. The exterior body 10 is located between the ventral portion 11 that mainly contacts the wearer's abdomen, the dorsal portion 12 that mainly contacts the wearer's back, and the ventral portion 11 and the dorsal portion 12. The crotch portion 13 which mainly abuts on the crotch portion of the wearer is included. The exterior body 10 mainly supports the absorbent main body 20 on the skin side surface of the inseam 13, and is arranged so that a part or all of the absorbent main body 20 overlaps the inseam 13. The absorbent body 20 absorbs and retains the wearer's body fluids.

It is preferable that the dimension in the longitudinal direction at the time of deployment of the pants-type absorbent article 1 before disposing the elastic elastic member is 600 mm or more and 1000 mm or less, and the dimension in the width direction is 450 mm or more and 900 mm or less. By setting the unfolded dimensions of the pants-type absorbent article 1 before arranging the elastic elastic member within the above range, the pants-type absorbent articles for adults of various sizes such as S size, M size, and L size can be used. Can be provided. The pants-type absorbent article 1 can be used as, for example, 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 the present embodiment will be described in more detail in the order of the absorbent main body 20 and the exterior body 10.

<Absorbable body>
The absorbent body 20 of the present embodiment has a liquid-permeable top sheet 21 relatively arranged on the skin side and a liquid-impermeable top sheet 21 arranged relatively on the non-skin side facing the top sheet 21. The sex back sheet 22, the absorber 23 arranged between the top sheet 21 and the back sheet 22, the perforated film 18 arranged between the top sheet 21 and the absorber 23, and the three-dimensional gather 24. , And the absorber 23 has a structure sandwiched between the top sheet 21 and the back sheet 22. The absorbent main body 20 is arranged so as to extend from the ventral side portion 11 to the dorsal side portion 12 mainly on the skin side surface of the inseam portion 13 of the exterior body 10. The absorbent body 20 is fixed to the exterior body 10 by an adhesive such as hot melt, heat fusion, ultrasonic bonding, or the like.

(Top sheet)
The base material of the top sheet 21 of the present embodiment may have liquid permeability such that the body fluid moves to the absorber 23, and for example, a non-woven fabric such as a thermal bond non-woven fabric and a thermal bond / spun bond are laminated. Examples thereof include a composite non-woven fabric, an open film such as an open polyethylene film, a foam film such as polyethylene foam and urethane foam, and a multi-layer sheet in which two or more of these are laminated. Further, it is preferable that the surface of the top sheet 21 is embossed or perforated in order to improve the liquid permeability. As the processing method, a known method can be performed without limitation. Further, in order to reduce irritation to the skin, it is also preferable that the top sheet 21 contains a lotion, an antioxidant, an anti-inflammatory component, a pH adjuster, an antibacterial agent, a moisturizer and the like. Further, 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 that covers the absorber 23 in order to guide a liquid such as urine to the absorber 23.

(Opening film)
As shown in FIG. 4, the opening film 18 of the present embodiment has a plurality of funnel-shaped convex portions 25 and an opening 26 formed near the top of the convex portion 25 (hereinafter, “funnel-shaped opening 26”). Also called) and. The perforated film 18 has a function of, for example, diffusing the body fluid discharged from the wearer and transferring the body fluid to the absorber. The perforated film 18 is arranged between the top sheet 21 and the absorber 23. The perforated film 18 has liquid permeability and liquid diffusivity such that body fluid moves to the absorber 23. As shown in FIG. 4, the perforated film 18 is preferably arranged so that the bottom of the funnel-shaped convex portion 25 faces the top sheet 21 in consideration of the rectifying action of the body fluid and the like. The basis weight of the perforated film 18 is preferably 20 g / m ² or more and 60 g / m ² or less, and more preferably 23 g / m ² or more and 30 g / m ² or less from the viewpoint of strength, workability and the like. If it is smaller than 20 g / m ² , the perforated film 18 tends to break easily, and ^{if it is larger than 60 g / m 2} , it tends to be hard to the touch.

From the viewpoint of liquid permeability, the number of funnel-shaped openings 26 (hereinafter, also referred to as “number of openings”) in the opening film 18 ^{is preferably 50 / cm 2} or more. When the number of pores is ^{less than 50 / cm 2} , the pore film 18 tends to be hard and the liquid permeability tends to decrease. Further, from the viewpoint of liquid diffusivity, the opening diameter is preferably 2 mm or less, more preferably 0.50 mm or more and 0.65 mm or less. If the opening diameter is smaller than 0.50 mm, the liquid permeability tends to deteriorate, and if it is larger than 0.65 mm, the strength, workability, etc. of the opening film 18 tends to decrease. The "opening diameter" is an average value obtained by photographing the opening film 18 with a 3D microscope (trade name: VR-3100, manufactured by KEYENCE CORPORATION) and measuring the diameters of three arbitrarily selected holes.
By setting the number of holes, the diameter of the holes, and the basis weight of the perforated film 18 within the above ranges, the perforated film 18 having excellent strength and workability and excellent liquid permeability and liquid diffusivity can be obtained.

The material of the perforated film 18 is not particularly limited as long as it is a synthetic resin that can be formed into a film, but a polyolefin-based resin is preferable, polyethylene and polypropylene are more preferable, and polyethylene is further preferable.

(Absorber)
As described above, the absorber 23 is a highly absorbent polymer (hereinafter referred to as “SAP”) supported as an absorbent component on a fiber aggregate (open fiber assembly) made of cellulose acetate tow and a fiber aggregate made of cellulose acetate tow. Also called), including. The dimension of the absorber 23 is not particularly limited, but the dimension of the longest width in the longitudinal direction is preferably 100 mm or more and 800 mm or less, and more preferably 150 mm or more and 500 mm or less. The length of the longest width of the absorber 23 in the width direction is preferably 50 mm or more and 500 mm or less, and more preferably 70 mm or more and 105 mm or less.

The highly absorbent polymer supported on the fiber aggregate composed of cellulose acetate tow is not particularly limited as long as it can absorb body fluids and prevent backflow, and polyacrylic acid salts, polyaspartate salts, etc. Examples thereof include a (starch / acrylic acid) graft copolymer, a (acrylic acid / vinyl alcohol) copolymer, a (isobutylene / maleic anhydride) copolymer, and a saponified product thereof. Among these, polyacrylate is preferable, and sodium polyacrylate is more preferable, from the viewpoint of the amount of absorption per weight. The highly absorbent polymer may be used alone or in combination of two or more.

The basis weight of the highly absorbent polymer supported on the fiber aggregate composed of cellulose acetate tow is preferably 240 g / m ² or more and 450 g / m ² or less, and more preferably 245 g / m ² or more and 445 g / m ² or less. By setting the basis weight of the highly absorbent polymer within the above numerical range, gel blocking in the absorber 23 can be prevented and a large amount of body fluid can be absorbed by the absorber 23.

The fiber aggregate composed of the cellulose acetate tow is not particularly limited, but it is preferably an spread fiber obtained by opening the cellulose acetate tow. The basis weight of the spread fiber of cellulose acetate tow is preferably 40 g / m ² or more and 90 g / m ² or less, and more preferably 45 g / m ² or more and 85 g / m ² or less. By setting the basis weight of the spread fiber within the above numerical range, it is possible to easily mass-produce the absorber 23 having good shape retention while maintaining the body fluid retention performance of the highly absorbent polymer at a high level.

In the absorber 23, the form of the fiber aggregate made of cellulose acetate tow and SAP may be formed by mixing SAP particles in cellulose acetate tow, and the SAP particles are fixed between the fiber aggregates made of cellulose acetate tow. The SAP sheet may be used. Further, the absorber 23 may be wrapped in a carrier sheet for the purpose of preventing leakage of SAP particles and stabilizing the shape of the absorber 23. The base material of the carrier sheet may be any one having hydrophilicity, and examples thereof include hydrophilic non-woven fabrics such as tissue, absorbent paper, and air-laid non-woven fabric. When a plurality of carrier sheets are provided, the base materials of the plurality of carrier sheets may be the same or different.

Further, in the absorber 23, the weight ratio of the highly absorbent polymer to the fiber aggregate composed of the cellulose acetate tow [(weight of the highly absorbent polymer / weight of the fiber aggregate composed of the cellulose acetate tow) × 100 (%)]. Is not particularly limited and is appropriately selected from a wide range depending on the use of the absorber 23 and the like, but is preferably 10% or more and 500% or less, and more preferably 20% or more and 300% or less. If the weight ratio is less than 10%, the absorption of body fluids such as urine discharged by the absorber 23 tends to be insufficient, and if it is more than 500%, SAP is sufficient for the fiber aggregate composed of cellulose acetate tow. It tends to fall off and fall without being supported by the body. Furthermore, gel blocking, which is caused by the swelling of a highly absorbent polymer that has absorbed body fluids such as urine, tends to occur. The weight ratio of the highly absorbent polymer to the fiber aggregate composed of cellulose acetate tow is 20% or more and 300% or less, which can sufficiently absorb body fluids such as excreted urine and is less likely to cause gel blocking. preferable.

The shape of the absorber 23 is not particularly limited, and is, for example, a rectangular shape, an hourglass shape, an I shape, a rectangular shape with rounded four corners, an oval shape, or an elliptical shape long in one direction. And so on. The absorber 23 may be used by stacking two or more layers.

(Back sheet)
The base material of the back sheet 22 of the present embodiment may be any one having liquid impermeable property so that the body fluid held by the absorber 23 does not leak, and a non-woven fabric, a resin film, and two or more of these are laminated. Examples include a multi-layer sheet. The non-woven fabric is not particularly limited in the manufacturing method, and examples thereof include spunbonded non-woven fabrics, melt-blown non-woven fabrics, spunbonded non-woven fabrics / melt-blow non-woven fabric laminates, spunbonded non-woven fabrics / melt-blow non-woven fabrics / spunbonded non-woven fabric laminates, and the like. Examples of the resin film include a polyester film, a polyvinyl alcohol film, a polyethylene film, a polypropylene film, a composite film of polyethylene and polypropylene, and the like. Further, in order to prevent stuffiness during wearing, the back sheet 22 preferably has moisture permeability. Examples of the method of imparting moisture permeability include blending a filler in the resin film of the base material and embossing the back sheet 22 for perforation.

(Three-dimensional gather)
The three-dimensional gather 24 is provided, for example, to prevent lateral leakage of body fluid. In the three-dimensional gather 24 of the present embodiment, one end in the width direction is fixed along the longitudinal direction near both ends in the width direction of the skin side surface of the back sheet 22, and the middle portion in the width direction is near both ends in the width direction of the skin side surface of the top sheet 21. A three-dimensional gather sheet 24b fixed along the longitudinal direction and having a free end at the other end in the width direction, and an arrangement along the longitudinal direction near the other end (free end) in the width direction and standing at the other end in the width direction. Includes an elastic stretchable member 24a for three-dimensional gathers that imparts properties. The other end in the width direction, which has erectability, can be expanded and contracted and deformed according to the wearer's body shape.

For the three-dimensional gather sheet 24b, for example, various non-woven fabrics can be used without limitation, and for the elastic elastic member 24a for three-dimensional gather, a general elastic elastic member such as thread rubber can be used without particular limitation. It should be noted that one end (fixed end) in the width direction of the three-dimensional gather sheet 24b joins the peripheral edge of the top sheet 21 and the peripheral edge of the back sheet 22 near both ends in the width direction of the skin side surface of the back sheet 22 to include the absorber 23. It may be fixed along the longitudinal direction to any of the vicinity of both ends in the width direction of the bag body, the vicinity of both ends in the width direction of the skin side surface of the top sheet 21, and the vicinity of both ends in the width direction of the non-skin side surface of the back sheet 22. The absorbent body 20 of this embodiment also includes an embodiment that does not include the three-dimensional gather 24.

<Exterior body>
The exterior body 10 is formed between the ventral portion 11 that mainly abuts on the ventral side of the wearer, the dorsal portion 12 that mainly abuts on the dorsal side of the wearer, and the ventral portion 11 and the dorsal portion 12. It has a crotch portion 13 that intervenes and mainly abuts on the crotch portion of the wearer, and mainly supports the absorbent body 20 on the skin surface side of the crotch portion 13. Further, as shown in FIGS. 2 and 3, the exterior body 10 of the present embodiment has a pair of left and right leg gathers extending from the ventral side portion 11 to the dorsal side portion 12 through the crotch portion 13 along the widthwise end portion. It has 16.

(Composite sheet)
A composite sheet 17 is used for the ventral portion 11 and the dorsal portion 12. By using the composite sheet 17, it is possible to reduce the gathers on the surface of the pants-type absorbent article 1 to bring it closer to the appearance of, for example, cloth underwear. In particular, when many gathers 110 as shown in FIG. 7 are present on the surface, the shape of the gathers 110 appears on the surface of the jacket even if the jacket is put on, so that the wear of the pants-type absorbent article 100 is recognized by others. There is a risk of On the other hand, in the present embodiment, as shown in FIG. 1, the amount of gathers on the surface can be significantly reduced by using the composite sheet 17. Therefore, the possibility that the wear of the pants-type absorbent article 1 will be recognized by others is greatly reduced. Further, since the composite sheet 17 arranged on the ventral side portion 11 and the dorsal side portion 12 has good breathability, the pants-type absorbent article 1 itself has excellent breathability and can be worn for a long time. It is very difficult for stuffiness to occur, and a good wearing feeling can be obtained.

The composite sheet 17 of the present embodiment is interposed between the two non-woven fabrics 14, the stretchable film 15 interposed between the two non-woven fabrics 14, and the non-woven fabric 14 and the stretchable film 15, and is interposed in the plane direction with each other. A plurality of adhesive portions 30 that are separated and that integrate the non-woven fabric 14 and the elastic film 15 are provided. The adhesive portion 30 is a portion where the non-woven fabric 14 and the elastic film 15 are adhered to each other. In the present specification, the integration of the non-woven fabric 14 and the elastic film 15 means that the non-woven fabric 14 and the elastic film 15 are adhered 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 or ultrasonic bonding for integrating the non-woven fabric 14 and the elastic 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 composed of the same composite sheet 17 as the ventral side portion 11 and the dorsal side portion 12, or may be composed of a non-woven fabric as in the conventional case. When the non-woven fabric is used as the exterior body of the inseam 13, it is preferable to use a laminated body of two or more layers of the non-woven fabric as in the conventional exterior body. The type of the non-woven fabric is not particularly limited, and for example, it can be selected and used from the same type as the non-woven fabric 14 described later.

The composite sheet 17 of the present embodiment is an integral body of two non-woven fabrics 14 and one elastic film 15 by an adhesive portion 30 of a laminate, but is not limited to this, and three or more non-woven fabrics 14 and , It may be an integrated product by the adhesive portion 30 of the laminated body with two or more elastic films 15 arranged between the non-woven fabrics 14. The composite sheet 17 may be a sheet having a three-dimensional shape having a flat surface and a layered shape having a cross-sectional view extending in one direction, and a wavy line shape having a cross-sectional view extending in one direction and having a regular surface. A sheet having a three-dimensional shape having specific irregularities may be used. From the viewpoint of texture, touch, cushioning, etc., the latter sheet having a wavy line shape in which the cross-sectional view extends in one direction is preferable.

The ventilation resistance value of the composite sheet 17 measured after being stretched 250% in the stretching direction 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 0.35 kPa · s / m or less. Since the composite sheet 17 has a ventilation resistance value in the above range, even if the absorbent main body 20 is fixed to the skin side surface of the inseam 13, it is better than the composite sheet 17 constituting the ventral side portion 11 and the dorsal side portion 12. Breathability is maintained. If the aeration resistance value is less than 0.01 kPa · s / m, the heat retention property of the pants-type absorbent article 1 tends to decrease, and the wearing feeling tends to decrease. If the aeration resistance value exceeds 0.5 kPa · s / m, the aeration of the pants-type absorbent article 1 is lowered, and there is a tendency for stuffiness to occur when worn.

The elongation rate of the composite sheet 17 in the expansion and contraction direction is preferably 150% or more and 270% or less, and more preferably 160% or more and 260% or less. Here, the elongation rate in the expansion / contraction direction is the ratio of the length increased by the expansion to the natural length in the non-expansion 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 expansion and contraction direction is within the above range, it is easy for the wearer to put on and take off, it is comfortable to wear with appropriate tightening, and it is a pants type that does not easily slip off and gives a sense of security. Absorbent article 1 is obtained.

The composite sheet 17 has an extension load of 0.8 N / 50 mm or more and 2.0 N / 50 mm or less when expanded 120% in the expansion / contraction direction, and 2.0 N / when expanded 150% in the expansion / contraction direction. It has an extension load of 50 mm or more and 3.5 N / 50 mm or less. Since the elongation rate changes depending on the body shape of the wearer, an extension load of 120% and 150% is specified. By doing so, there is no difference in fit depending on the body shape. Further, the composite sheet 17 has an elongation rate of 200% or more and 270% or less in the expansion / contraction direction. For this reason, since it is possible to stretch 200% or more as compared with the conventional case, it is possible to provide the pants-type absorbent article 1 which is easy for the wearer to put on and take off. Here, the elongation rate in the expansion / contraction direction is the ratio of the length of the extension to the natural length in the non-expansion state, as in the case of expansion of 120% in the expansion / contraction direction. The extension load can be measured using, for example, an autograph manufactured by Shimadzu Corporation.

Further, the composite sheet 17 preferably has a breaking elongation of 210% or more and 280% or less in the expansion / contraction direction. The breaking elongation is defined as the breaking elongation = where the length of the composite sheet 17 which is in the natural length in the non-stretchable state is L1 and the length when the composite sheet 17 is stretched in the stretching direction and broken is L2. (L2 / L1) × 100 (%). By having the breaking elongation in this range, there is an effect that the pants are less likely to be stretched or torn even if the pants are widely spread when putting on and taking off. The elongation at break can be measured using, for example, an autograph manufactured by Shimadzu Corporation.

As the non-woven fabric 14 constituting the composite sheet 17 of the present embodiment, any non-woven fabric conventionally used for the exterior body of the pants-type absorbent article can be used. Two or more types of laminated fabrics and the like can be mentioned. Two or more types of laminates are joined by, for example, a hot melt adhesive, heat welding, ultrasonic welding, or the like. The non-woven fabric 14 preferably contains fibers made of a thermoplastic resin such as polyethylene, polypropylene, and polyester as constituent fibers. When the composite sheet 17 contains a plurality of non-woven fabrics 14, the non-woven fabrics 14 may be different or the same. From the viewpoint of obtaining the composite sheet 17 having a predetermined ventilation resistance value and elongation rate in the expansion / contraction direction, the basis weight of the non-woven 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 40 g / m ² 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 of being stretched in the stretchable direction (a state in which the stretch ratio in the stretchable direction is within a predetermined range). The stretchable sheet is not particularly limited as long as it has elasticity, but a film made of a synthetic resin that exhibits elasticity by forming a film is preferable. Examples of the synthetic resin include polyester-based elastomers, polyolefin-based elastomers, polyurethane-based resins, polyamide-based resins, and two or more alloys thereof. Among these, a film containing a polyurethane-based resin is preferable, and a film made of a polyurethane-based resin is more preferable, from the viewpoint of cost and stretchability. From the viewpoint of obtaining the composite sheet 17 having a predetermined airflow resistance value and the elongation rate in the expansion / contraction direction, the thickness of the elastic film 15 is preferably 8 μm or more and 40 μm or less, and the elongation rate in the expansion / contraction direction of the elastic film 15 is preferable. It is 100% or more and 350% or less.

FIG. 5 is a schematic plan view showing an enlarged example of the planar shape and arrangement pattern of the adhesive portion 30 on the surface of the composite sheet 17. As shown in FIG. 5, the composite sheet 17 is integrated by a plurality of adhesive portions 30 having a planar shape in which a quadrangle and a circle are combined in a plan view. The adhesive portion 30 has a planar shape in which a corner portion derived from a quadrangle and a partial arc line derived from a circle are connected, and preferably a plurality of the corner portions derived from the quadrangle and a plurality of the corner portions derived from the circle. It has a planar shape in which the partial arc line of the above is connected.

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

Since the composite sheet 17 integrated with a plurality of adhesive portions 30 having such a planar shape has appropriate mechanical strength, elasticity, and tightening property, gathers can be formed by arranging elastic elastic members. It is very suitable as an exterior body of the pants-type absorbent article 1 because it is not required and the low air permeability, which is a drawback of the conventional composite sheet, is improved.

In FIG. 5, a preferable example of each dimension of the adhesive portion 30 is shown. The dimension (length in the expansion / contraction direction) of the rectangular 40 portion of the adhesion portion 30 represented by the reference numeral “A” is extended by 250% in the expansion / contraction direction Y. Sometimes 0.2 mm or more and 0.4 mm or less, and the dimension in the direction substantially orthogonal to the expansion and contraction direction Y of the adhesive portion 30, which is indicated by the reference numeral "B", is 0.8 mm or more and 2.0 mm or less, and the reference numeral. The diameter of the circle 41 portion of the bonding portion 30 indicated by "C" is 0.3 mm or more and 0.8 mm or less, and the shortest length of the bonding portion 30 adjacent to the expansion / contraction direction Y indicated by the reference _{numeral "D 1".} When the composite sheet 17 is stretched 250% in the stretching direction Y, it is 1.0 mm or more and 3.0 mm or less, and is adjacent to each other in a direction substantially orthogonal to the stretching direction Y, which is indicated by the reference _{numeral “D 2”.} The shortest length of the bonded portion 30 is 1.0 mm or more and 3.0 mm or less, and the shortest length of the bonded portion 30 adjacent to the expansion / contraction direction Y in the arrangement Y represented by the reference numeral “E” is the composite sheet 17. When extended by 250% in the expansion / contraction direction Y, it is 2.0 mm or more and 5.0 mm or less. By setting the adhesive portion 30 in the above range, the air permeability of the composite sheet 17 is further improved, and the decrease in the durability of the stretchable film 15 is alleviated.

The composite sheet 17 preferably has an adhesive area ratio of 4% or more and 18% or less of the adhesive portion 30. Here, the adhesive area ratio indicates the ratio of the total area of the adhesive portions 30 existing in the unit area to the unit area of the composite sheet 17 as a percentage. If the adhesive 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 production method shown in FIG. FIG. 5 is a drawing schematically showing a manufacturing method of the composite sheet 17. FIG. 6A is a schematic side view showing all the steps of the method for manufacturing the composite sheet 17. FIG. 6B is a schematic cross-sectional view showing an enlarged third step (adhesion step). The manufacturing method shown in FIG. 6 is a method using ultrasonic bonding or heat fusion, and includes the first to third steps in this order.

In the first step, the stretchable film 15 wound around the feed roller 51 is conveyed while being loaded with a predetermined tension. The stretchable film 15 is conveyed while being stretched in the conveying direction by a predetermined tension. The predetermined tension is a tension that stretches the stretchable film 15 by 200% or more, more preferably 250 ± 30%.

In the second step following the first step, each non-woven fabric 14 wound around the two feeding rollers 52 is laminated on the upper and lower sides of the stretchable film 15 conveyed in the stretched state to obtain a laminated body before integration.

In the third step following the second step, the laminated body before integration is passed through the pressure-welding portions (hereinafter, also referred to as “nip portions”) of the first and second joining rollers 53 and 54, and the predetermined bonding portion 30 is formed. They are integrated so as to be formed to obtain a composite sheet 17. The peripheral surface of the first joining roller 53 is provided with a plurality of recesses 55 extending in the width direction and having a predetermined size and a predetermined internal space shape at predetermined intervals in the circumferential direction. The second joining roller 54 is a convex portion having a predetermined size and a predetermined three-dimensional shape (a three-dimensional shape in which the tip portion can be inserted into the recess 55 under the intervention of the laminated body) extending in the width direction on the peripheral surface thereof. A plurality of 56s are provided at predetermined intervals in the circumferential direction. The first and second joining rollers 53 and 54 are meshed with each other so that the tip portion of the convex portion 56 can be inserted into the concave portion 55, and are pressure-welded with a predetermined pressure. Seal lines substantially continuous in the width direction of the roller peripheral surface are formed in the nip portions of the first and second joining rollers 53 and 54 at intervals of 0.5 mm or more and 2.0 mm or less in the expansion and contraction direction. There is. One or both of the first and second joining rollers 53 and 54 are provided with an ultrasonic generator or a heating device, and can apply ultrasonic waves to at least the tip portion of the inner wall surface of the concave portion 55 or the convex portion 56. Alternatively, it is configured to be heatable.

In the third step, the laminate obtained in the second step is passed through the nip portions of the first and second joining rollers 53 and 54 under pressure to form an inner wall surface of the concave portion 55 and a tip portion of the convex portion 56. By ultrasonically applying or heating the seal wire, which is the contact point of the non-woven fabric 14, a plurality of adhesive portions 30 having a predetermined planar shape are formed, and the non-woven fabric 14 and the elastic film 15 are integrated by the plurality of adhesive portions 30. A composite sheet 17 having less surface wrinkles and a smooth feel can be obtained. That is, a plurality of adhesive portions 30 having a planar shape shown in FIG. 5 are formed at predetermined intervals shown in FIG. A composite sheet 17 in which the non-woven fabric 14 and the elastic film 15 are integrated is obtained.

(Leg gather)
As shown in FIGS. 2 and 3, the leg gather 16 includes an elastic elastic member 16a and a leg gather sheet 16b. The elastic elastic member 16a is not particularly limited, and for example, thread rubber or the like can be used. As the leg gather sheet 16b, for example, various non-woven fabrics and the like can be used. By providing the leg gathers 16, it is possible to expand and contract not only in the expansion and contraction direction (width direction) but also in the direction intersecting the expansion and contraction direction (longitudinal direction), and the fit feeling in the portion around the inseam is improved. The shape of the leg gather 16 is unlikely to appear on the surface of the clothes when the pants-type absorbent article 1 is worn and worn.

<Manufacturing method of pants-type absorbent articles>
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 side portion 11 and the dorsal side portion, or the ventral side portion 11, the dorsal portion 12, and the crotch portion 13. It can be produced in the same manner as a sex article. For example, the ventral side portion 11 and the dorsal side portion 12 are manufactured from the composite sheet 17, the crotch portion 13 is composed of a laminated body of conventional non-woven fabrics, and these are joined in a predetermined order in the longitudinal direction to obtain an exterior body 10. The process, the step of fixing the absorbent body 20 to a predetermined position (mainly the crotch portion 13) on the skin side surface of the exterior body 10, and the leg gathers 16 near both ends of the absorbent body 20 on the skin side surface of the exterior body 10 in the width direction. The pants-type absorbent article 1 can be obtained by a manufacturing method including the step of arranging the above. The pants-type absorbent article 1 thus obtained is commercialized by folding it in a predetermined order and packing it in a bag.

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 above embodiments. Further, it is clear from the description of the scope of claims that the form to which such a modification or improvement is added may be included in the technical scope of the present invention.

Hereinafter, the present invention will be described in detail with reference to examples. The present invention is not limited to the examples shown below.

<Examples 1 to 3 and Comparative Examples 1 to 3>
A disposable diaper was produced as a pants-type absorbent article.
The exterior bodies of the ventral, dorsal, and crotch parts have the planar shape and arrangement shown in FIG. 5 (arrangements X and Y are arranged alternately in the direction perpendicular to the row), and are front-facing. By each of the adhesive portions of Examples 1 to 3 having each dimension shown in 1 (each dimension of A, B, C, D ₁ , D _{2 and E shown in FIG. 5) and formed by ultrasonic bonding, 2} A polyurethane film (thickness 20 μm, expansion / contraction rate 250% in the expansion / contraction direction) was arranged between sheets of polypropylene spunbonded non-woven fabric (basis weight 20 g / m ^{2), and an integrated composite sheet was used.} 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 a circle (Comparative Example 1) or a rectangle (Comparative Examples 2 and 3).

Further, the top sheet is an air-through non-woven film having a basis weight of 30 g / m ² , and the perforated film is a perforated polyethylene film having a funnel-shaped convex portion on the surface and perforations located around the top of the convex portion (basis weight 26 g / m 2). m ² , number of holes 60 / cm ² , hole diameter 0.60 mm), ^{a breathable polyethylene film with a basis weight of 32 g / m 2} is used as the back sheet, and a cellulose acetate tow is placed between the top sheet and the back sheet. An absorbent body consisting of a mixture of 3.0 g of an open fiber (basis weight 70 g / m ² ) and 8.0 g of SPA is placed, and a perforated polyethylene film is placed between the top sheet and the absorbent body to absorb the main body. Was prepared and bonded to the skin side surface of the crotch part of the exterior body with a hot melt adhesive. In addition, two undercarriage of 940 decitex urethane thread rubber extending in the longitudinal direction are arranged on the skin side surface of the exterior body at both ends in the width direction of the absorbent body in a state of being stretched to 000%. Gathers were joined to produce a pants-type absorbent article.

A test piece for measurement in which the ventral side was cut out from each of the pants-type absorbent articles of Examples 1 to 3 and Comparative Examples 1 to 3 was used as a "one-shot 3D measurement macroscope VR-3100" manufactured by KEYENCE CORPORATION. The non-skin side surface was photographed in a state of being stretched to 250%, and each dimension of the adhesive portion (each dimension of 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 carried out on 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)
The measurement test piece obtained by cutting out the ventral side from each of the pants-type absorbent articles of Examples 1 to 3 and Comparative Examples 1 to 3 was once stretched 250% in the stretching direction, and then the stretching was released, and Katou Tech ( The aeration resistance value R (kPa · s / m) was measured using a “breathability 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 at a sample width of 50 mm (direction perpendicular to the stretching direction) was measured.

(Evaluation of elasticity, fit, and flexibility of exterior parts)
Each of the pants-type absorbent articles of Examples 1 to 3 and Comparative Examples 1 to 3 was worn by 20 monitors, and had elasticity (whether or not it was easy to wear), fit, and flexibility of the exterior body part. (Whether or not it has a soft touch and texture) was subjected to a sensory evaluation. Regarding the sensory evaluation, both evaluations were conducted by selecting "good" and "bad", and evaluated according to the following criteria.
〇: When "good" is 12 or more and 20 or less △: When "good" is 5 or more and 11 or less ×: When there is no "good" or 1 or more and 4 or less

1 Pants-type absorbent article 10 Exterior body 11 Ventral side 12 Dorsal side 13 Inseam 14 Non-woven fabric 15 Elastic film 16 Leg gather 17 Composite sheet 18 Perforated film 20 Absorbent body 21 Top sheet 22 Back sheet 23 Absorbent 24 Three-dimensional gather 25 Funnel-shaped convex part 26 Opening (hole)

Claims (7)

An absorbent body including a liquid-permeable top sheet, a liquid-impermeable back sheet, and an absorber disposed between the top sheet and the back sheet, and a ventral portion supporting the absorbent body. A pants-type absorbent article comprising an exterior body divided into an inseam and a dorsal part.
The absorbent body comprises a perforated film having a plurality of funnel-shaped perforations arranged between the topsheet and the absorber.
The absorber contains, as an absorbent component, a fiber aggregate made of cellulose acetate tow and a highly absorbent polymer supported on the fiber aggregate made of the cellulose acetate tow.
The ventral portion and the dorsal portion are a plurality of non-woven fabrics, a plurality of elastic films arranged between the non-woven fabrics, and a plurality of non-woven fabrics and the elastic film which are separated from each other in the surface direction to integrate the non-woven fabric and the elastic film. Equipped with a composite sheet including an adhesive part,
Each of the adhesive portions is a pants-type absorbent article having a planar shape in which a corner portion derived from a quadrangle and a partial arc line derived from a circle are connected. The pants-type absorbent article according to claim 1, wherein the adhesive portion has a planar shape in which a plurality of the corner portions derived from a quadrangle and a plurality of the partial arc lines derived from a circle are connected. The pants-type absorbent article according to claim 1 or 2, wherein the composite sheet is an integrated product including the bonded portion by heat fusion and / or ultrasonic bonding. The pants-type absorbent article according to any one of claims 1 to 3, wherein the composite sheet has an elongation rate of 150% or more and 270% or less in the expansion and contraction direction. The weight ratio of the fiber aggregate composed of the cellulose acetate tow to the highly absorbent polymer (weight of the highly absorbent polymer / weight of the fiber aggregate composed of the cellulose acetate tow) is 10% or more and 500% or less. The pants-type absorbent article according to any one of claims 1 to 4. The perforated film has a perforation diameter of 2 mm or less, a perforation number of 50 or more / cm ² , and a basis weight of 20 g / m ² or more and 60 g / m ² or less, according to any one of claims 1 to 5. The pants-type absorbent article described. The pants-type absorbent article according to any one of claims 1 to 6, further comprising an elastic elastic member disposed from the ventral side to the crotch portion and extending to the dorsal side.

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