CN116056675A - Pants-type absorbent article - Google Patents

Abstract

In a composite stretchable portion (10E) in a natural state, an inner sheet (12) has a gather structure composed of a plurality of concave strip portions (120) having a joint portion (13) at the bottom and extending in the longitudinal direction (X), and convex strip portions (121) located between the concave strip portions (120) and having a curved portion (12P) of the inner sheet (12) as the top, and an outer sheet (11) has a plurality of curved portions (11P) in a region overlapping with 1 convex strip portion (121) of the inner sheet (12) in a plan view. At least one of the abdomen side part (A) and the back side part (R) is provided with an outer body folding-back part (14), and the outer body folding-back part (14) comprises a part of the composite expansion part (10E) folded back in a manner that the inner layer sheet (12) is folded back inside.

Description

Pants-type absorbent article

technical field

The present invention relates to underpants-type absorbent articles such as underpants-type disposable diapers.

Background technique

A pants-type disposable diaper, which is a kind of pants-type absorbent article, typically has the following structure: an absorbent main body including an absorber, and an exterior body arranged on the non-skin-facing side of the absorbent main body, and Both side edge portions along the longitudinal direction of the front body portion and the rear body portion are joined to each other to form a pair of side joint portions, a waist opening portion, and a pair of leg opening portions. In the underpants-type disposable diaper of such a structure, in order to improve the fit to the body of the wearer, the outer body between the waist opening and the leg opening is arranged at intervals in the longitudinal direction. Multiple elastic members fixed elongately. In addition, the longitudinal direction is a direction corresponding to the front-back direction of the wearer, and the transverse direction is a direction perpendicular to the longitudinal direction.

Patent Document 1 describes that as an exterior body in a pants-type disposable diaper, an exterior body having a structure including an outer layer sheet located on the outer surface side of the diaper, an inner layer sheet located on the inner surface side of the diaper, and The plurality of elastic members arranged between the two sheets are formed with gathers by the composite expansion and contraction part. In the above-mentioned composite stretchable portion, the outer layer sheet and the inner layer sheet are joined by a large number of joints distributed in both the stretching direction (transverse direction of the diaper) and the direction perpendicular to it (longitudinal direction of the diaper) of the composite stretchable portion, and the elastic The member is arranged so as not to pass through the joint portion, and both ends in the longitudinal direction of the elastic member are fixed between two sheets each forming a plurality of strips extending continuously over the plurality of elastic members. Wrinkles, where the size of the pleats differs between the outer sheet and the inner sheet. According to the underpants-type disposable diaper described in Patent Document 1, the composite stretchable portion is excellent in air permeability and flexibility, and has different cushioning properties on the front and back sides of the exterior body.

Patent Document 2 describes that, as an exterior body of a pants-type disposable diaper, an exterior body having an elastic composite part having a stretch sheet and a non-stretch sheet bonded to the surface facing the stretch composite part is described. In the above-mentioned stretchable composite part in the natural state, a large number of first ridges are formed on the surface of the non-stretch sheet side, and a large number of second ridges lower in height than the first ridges are formed on the surface of the stretch sheet. As for the strip part, the first convex strip part is arranged so as to be able to contact the wearer's skin. According to the underpants-type disposable diaper described in Patent Document 2, cushioning is provided by the ridges on the side that contacts the wearer's skin, and since the ridges are arranged on the outer side that are lower than the height, the appearance is reduced. The heaviness of the fabric allows for an underwear-like look and feel.

In Patent Document 3, it is described that the exterior body near the waist opening of the underpants type disposable diaper, in a natural state, each has a plurality of inner layer sheet surfaces and outer layer sheet surfaces spaced at intervals in the circumferential direction of the waist opening. Wrinkles, the spacing between the wrinkles on the surface of the inner layer sheet is smaller than the spacing between the wrinkles on the surface of the outer layer sheet. According to the underpants-type disposable diaper described in Patent Document 2, good cushioning performance can be obtained by the folds of the inner layer sheet on the side that contacts the wearer's skin, and the outer surface side of the diaper is provided by the relatively large pitch of the outer layer sheet. The pleats reduce the bulk of the appearance, enabling an underwear-like appearance.

prior art literature

patent documents

Patent Document 1: Japanese Patent Laid-Open No. 2009-297096

Patent Document 2: Japanese Patent Laid-Open No. 2010-284228

Patent Document 3: Japanese Patent Laid-Open No. 2010-284229

Contents of the invention

The present invention relates to a pants-type absorbent article, which has a longitudinal direction extending from the wearer's abdominal side through the crotch portion to the back side and a transverse direction perpendicular to the longitudinal direction, and is divided into a crotch portion disposed on the wearer's crotch portion. The absorbent article has an absorbent main body including an absorbent body, and the exterior body disposed on the non-skin facing side of the absorbent main body,

Both side edge parts along the said longitudinal direction of the said exterior body of each of the said abdominal part and the said back side part are joined to each other, and the waist opening part and a pair of leg part opening part are formed.

In one embodiment of the underpants-type absorbent article of the present invention, the exterior body preferably includes an outer layer sheet arranged relatively far from the absorbent body, and an inner layer sheet arranged relatively close to the absorbent body.

In one embodiment of the underpants-type absorbent article of the present invention, it is preferable that at least a part of the outer casing is a composite stretchable portion having stretchability in the lateral direction, and at the composite stretchable portion, the outer layer sheet and the inner layer sheet Joined by a plurality of joining parts arranged at intervals in the above-mentioned transverse direction.

In one embodiment of the underpants-type absorbent article of the present invention, it is preferable that the inner-layer sheet has a gather structure at the above-mentioned complex expansion-contraction portion in a natural state. Consists of a plurality of grooves and a ridge between the grooves and with the curved portion of the inner layer sheet as the top, and the outer layer sheet is viewed from above with one of the ridges of the inner layer sheet. There are multiple bends in the overlapping region.

In one embodiment of the underpants-type absorbent article according to the present invention, it is preferable that at least one of the abdominal portion and the back portion is provided with a foldable portion including the composite stretchable portion so that the inner layer sheet is folded inside. A part of the exterior body is folded back.

Other features, effects, and embodiments of the present invention will be described below.

Description of drawings

Fig. 1 is a perspective view schematically showing a pants-type disposable diaper which is one embodiment of the pants-type absorbent article of the present invention.

Fig. 2 is a developed plan view schematically showing a partially cutaway skin-facing surface (inner surface) side of the developed and stretched state of the diaper shown in Fig. 1 .

Fig. 3 is an exploded perspective view schematically showing the disassembled diaper shown in Fig. 1 .

Fig. 4 is a cross-sectional view schematically showing a cross-section along line I-I in Fig. 2 .

Fig. 5 is a longitudinal sectional view schematically showing a section along line II-II in Fig. 2 .

Fig. 6 is a partially cutaway perspective view schematically showing an example of a stretch sheet usable as an outer layer sheet of the diaper shown in Fig. 1 .

Fig. 7 is a cross-sectional view schematically showing a section along line III-III in Fig. 5, and is a cross-sectional view of the folded-back portion of the exterior body in the natural state of the diaper shown in Fig. 1 .

Fig. 8 is a schematic perspective view of the folded-back portion of the exterior body in the natural state shown in Fig. 7 .

FIG. 9 is a schematic cross-sectional view of a composite telescopic portion constituting the folded-back portion of the exterior body shown in FIG. 7 .

Fig. 10 is a view corresponding to Fig. 7 of another embodiment of the folded-back portion of the exterior body of the present invention.

Detailed ways

As one of the main wearers of the underpants type disposable diaper, infants of a young age can be exemplified. Usually, young infants spend a long time in the sleeping position when wearing diapers. During this period, the waist area of the diaper's outer body strongly presses the wearer's skin, so it is easy to form pressure marks on the skin. There is a possibility of burdening the skin. In addition, when an infant wearing a diaper is in a sleeping position for a long time, the air permeability of the portion of the diaper that strongly presses the wearer's skin decreases, which may cause problems such as stuffiness. Conventional underpants-type absorbent articles have room for improvement in terms of cushioning properties, air permeability, and the like of the exterior body.

Therefore, the present invention relates to an underpants-type absorbent article that has an exterior body excellent in cushioning properties and air permeability, and is less likely to cause pressure marks on the skin of a wearer who is often in a sleeping position, and less likely to be stuffy.

Hereinafter, the present invention will be described based on its preferred embodiments with reference to the drawings. In addition, in the description of the drawings below, the same or similar reference numerals are attached to the same or similar parts. The drawings are basically schematic diagrams, and ratios of dimensions may be different from actual ratios of dimensions.

The pants-type absorbent article of the present invention has a longitudinal direction corresponding to the front-rear direction of the wearer, that is, a direction extending from the abdominal side to the back side via the crotch portion (the direction indicated by the reference symbol "X"), and a vertical direction corresponding to the longitudinal direction. Transverse direction of intersection (direction denoted by reference numeral "Y").

In the following description, unless otherwise specified, the longitudinal direction refers to the longitudinal direction of the absorbent article or the direction along the longitudinal direction of its constituent parts (such as the absorbent body), and the transverse direction refers to the transverse direction of the absorbent article or its constituent parts along the transverse direction. direction.

The pants-type absorbent article of the present invention is divided into: a crotch portion arranged in the crotch portion of the wearer (the part indicated by reference numeral "B"); side portion (the part represented by the reference sign "A"); and the back side part (the part represented by the reference sign "C") arranged closer to the wearer's back side than the crotch part, and has an absorbent body (the component indicated by the reference numeral "5"), the absorbent main body (the component indicated by the reference numeral "2"); and the exterior body (the reference numeral indicated by "10" indicates the part).

In this specification, the "skin-facing surface" refers to the surface facing the wearer's skin side when the absorbent article is worn, that is, the surface relatively close to the wearer's skin, in the absorbent article or its constituent parts (such as the outer casing). One side, the "non-skin-facing surface" is the surface facing the side opposite to the skin side when the absorbent article is worn, that is, the side relatively away from the wearer's skin in the absorbent article or its component parts. In addition, "at the time of wearing" demonstrated here means being in a normal appropriate wearing position, ie, the state which maintains the correct wearing position of this absorbent article.

In the pants-type absorbent article of the present invention, the outer casings of the abdominal portion and the back portion are joined to each other on both side edges in the longitudinal direction to form a waist opening (the part indicated by the reference numeral "WH") ) and a pair of leg openings (parts denoted by reference numeral "LH").

The underpants type disposable diaper 1 which is one embodiment of the underpants type absorbent article of this invention is shown in FIGS. 1-5, and the diaper 1 has the above-mentioned structure.

In this embodiment, both side edge parts 10S along the longitudinal direction X of the exterior body 10 of each of the abdominal part A and the back part C are joined together, and a pair of side joint part S is formed. The method of joining the exterior bodies 10 at the side joint portion S is not particularly limited, and examples thereof include welding, adhesives, sewing, and the like. Typically, the joining method of the exterior bodies 10 in the side joints S of the underpants-type disposable diaper is welding and/or adhesives, and the exterior bodies 10 in the side joints S of the underpants-type sanitary shorts The preferred joining method is suture. The side joining portion S of the present embodiment is a so-called side seal portion in which both side edge portions 10S of the exterior body 10 are joined by welding, and protrudes outward from the peripheral portion as shown in FIG. 1 .

The diaper 1 is divided into a front body F and a rear body R. As shown in FIG. As shown in FIG. 2, the front body part F is based on the longitudinal centerline CLx that bisects the diaper 1 in the unfolded and stretched state in the longitudinal direction X and extends in the transverse direction Y, and covers the wearer's body when worn. The ventral (front) part and the rear body R are parts covering the back (rear) of the wearer's body. The "expanded and stretched state" as used herein means that the diaper 1 is incised at the side joints S to be in the unfolded state, and the diaper 1 in the unfolded state is expanded until the elastic members of each part are stretched to a design size. (the same size as when it expands to a flat shape in a state where the influence of all elastic members is excluded).

The ventral part A is a part of the front part F, and the back part C is a part of the rear part R. FIG. The crotch portion B spans the longitudinal center line CLx in the longitudinal direction X, and exists in a range from the front body portion F to the rear body portion R. As shown in FIG. Each of the abdominal part A and the back part C is typically a part at the same position as the side joint part S in the longitudinal direction X. The crotch part B typically includes a region in which notches for forming the leg openings LH and LH, that is, leg edge parts LS and LS are formed on both side edges 10S along the longitudinal direction X of the exterior body 10, and includes The excretion part facing part is arrange|positioned facing the excretion part, such as a wearer's penis, at the time of wearing of the diaper 1.

In the present invention, the abdominal part A, the crotch part B, and the back part C may be each region when the diaper 1 in an unfolded and stretched state is divided into three equal parts in the longitudinal direction X.

In this embodiment, as shown in FIG. 2 , the ventral part A and the dorsal part C respectively have: an ilium region D2 corresponding to the wearer's position from the iliac crest to the anterior superior iliac spine; The waist region D1 on the outer side (above the diaper 1 ) in the longitudinal direction X; and the buttocks region D3 located in the inner side (below the diaper 1 ) than the region D2 in the longitudinal direction X. The iliac crest and anterior superior iliac spine mentioned here are anatomical terms. The waist region D1 is located on the outermost side in the longitudinal direction X of each of the abdominal part A and the back part C, and includes the longitudinal end 1E which is one of both ends of the longitudinal direction X of the diaper 1 . The longitudinal end 1E of the diaper 1 is also the longitudinal end of the exterior body 10 .

In the present invention, the lumbar area D1, the ilium area D2, and the buttocks area D3 may be three-dimensionally aligned in the longitudinal direction X with the ventral portion A or the dorsal portion C (the portion at the same position as the side joint portion S in the longitudinal direction X). Each region of the case is equally divided.

In addition, in the present embodiment, the abdominal part A and the back part C have basically the same structure, and unless otherwise specified, the description about any one can also be applied to the other.

In this embodiment, the absorbent main body 2 has a rectangular shape in plan view, its longitudinal direction coincides with the longitudinal direction X of the diaper 1, is arranged at the center of the outer body 10 in the horizontal direction Y, and extends from the abdominal part A in the longitudinal direction X. to the dorsal part C. The absorbent body 2 is bonded to the exterior body 10 with an adhesive.

As shown in FIGS. 4 and 5 , the absorbent main body 2 includes an absorber 5 , a liquid-permeable front sheet 3 disposed on the skin-facing side of the absorber 5 , and a liquid-permeable front sheet 3 disposed on the non-skin-facing side of the absorber 5 . Leak-proof (specifically, liquid-impermeable, liquid-impermeable, or water-repellent) backsheet 4 is configured. The absorbent body 5 includes at least an absorbent core mainly composed of water-absorbent materials such as wood pulp and water-absorbent polymers, and may include paper, inorganic Spinning etc. As the constituent members of the absorbent main body 2 , members generally used in such absorbent articles can be used without particular limitation. For example, various nonwoven fabrics, apertured films, and the like can be used as the top sheet 3 . A resin film, a laminated sheet of a resin film and a nonwoven fabric, or the like can be used as the back sheet 4 . The components of the absorptive main body 2 are integrally formed by a known bonding method such as an adhesive.

On both sides of the skin-facing surface (side of the front sheet 3) of the absorbent main body 2 along the longitudinal direction X, a pair of sheets 60 for forming leak-proof cuffs that are liquid-resistant or water-repellent and air-permeable are provided. Leakproof flanging 6,6. One or a plurality of thread-shaped leak-proof cuff-forming elastic members 61 are fixed in a longitudinal direction X so as to be stretchable at the free end of each leak-proof cuff 6 . The anti-leakage cuff 6 is contracted by the elastic member 61 to stand up toward the wearer's skin at least in the crotch portion B, thereby preventing bodily fluids from flowing out in the lateral direction Y. In addition, the underpants-type absorbent article of the present invention may not have the leak-proof cuff 6 .

Hereinafter, the exterior body 10 which is the main part of the diaper 1 is demonstrated in detail. The exterior body 10 includes an outer-layer sheet 11 arranged relatively far from the absorber 5 , and an inner-layer sheet 12 arranged relatively close to the absorber 5 .

In this embodiment, when the exterior body 10 is in the unfolded and stretched state of the diaper 1 as shown in FIG. Arc-shaped, the portion corresponding to the abdominal part A and the back part C (the end region in the longitudinal direction X) has a rectangular shape in which the length in the horizontal direction Y is longer than that in the longitudinal direction X, and the exterior body 10 as a whole has an hourglass shape.

As shown in Fig. 3 and Fig. 5, the outer layer sheet 11 includes an abdominal outer layer sheet 11A corresponding to the abdominal part A, a crotch outer layer sheet 11B corresponding to the crotch part B, and a back part corresponding to the back part C. Side outer layer sheet 11C. Each outer layer sheet 11A, 11B, 11C forms the outer surface of the diaper 1 . Outer-layer sheets 11A, 11B, and 11C are formed by overlapping their ends in the longitudinal direction X, and joining each other at the overlapped portions by a known joining method such as an adhesive, heat sealing, high-frequency sealing, or ultrasonic sealing. integration. In the overlapping portion of the sheets 11A, 11C and the sheet 11B, the sheet 11B located in the center of the longitudinal direction X is located on the side relatively close to the absorbent main body 2, and the non-skin-facing surfaces at both ends of the longitudinal direction X of the sheet 11B are respectively covered with sheets. 11A, 11C are covered (refer FIG. 5).

The inner layer sheet 12 includes an abdominal inner layer sheet 12A corresponding to the abdominal part A and a back inner layer sheet 12C corresponding to the back part C. As shown in FIG. The two sheets 12A, 12C are arranged in a state separated from each other.

In the present invention, the outer-layer sheet 11 and the inner-layer sheet 12 may be in the form of one continuous sheet instead of including such a plurality of sheets.

In addition, the following description about the outer layer sheet 11 can be applied to each sheet|seat 11A, 11B, 11C unless otherwise specified. In addition, the following description about the inner-layer sheet 12 is applicable to the abdominal inner-layer sheet 12A and the back-side inner-layer sheet 12C unless otherwise specified.

The outer-layer sheet 11 and the inner-layer sheet 12 may be of the same kind or different kinds of sheets. In this embodiment, as will be described later, the former includes an elastic sheet, and the latter is composed of a non-elastic sheet, and they are sheets of different types from each other.

The plurality of sheets 11A, 11B, and 11C constituting the outer layer sheet 11 may be sheets of the same type or different types of sheets. In this embodiment, the abdominal outer layer sheet 11A and the back outer layer sheet 11C are sheets of the same type (stretch sheet 20 ), but the two sheets 11A, 11C and the crotch outer layer sheet 11B are sheets of different types. (non-stretch sheet).

The plurality of sheets 12A and 12C constituting the inner layer sheet 12 may be sheets of the same type or different types of sheets. In this embodiment, the abdominal inner-layer sheet 12A and the back-side inner-layer sheet 12C are mutually the same kind of sheet (non-stretchable sheet).

In addition, in this specification, "the same kind of sheet" refers to sheets having the same production process of the sheet, the type of the constituent fiber of the sheet, the fiber diameter and length of the constituent fiber, the thickness or the basis weight of the sheet, and the like. When at least one of them is different, it is "a different kind of sheet".

The grammage of the outer layer sheet 11 (the grammage of the laminated structure when the outer layer sheet 11 is a laminated structure) is not particularly limited, but is preferably 20 g/m ^or more, more preferably 30 g/m or ^more , and preferably It is 60 g/m ² or less, more preferably 55 g/m ² or less.

The grammage of the inner layer sheet 12 (the grammage of the laminated structure when the inner layer sheet 12 is a laminated structure) is not particularly limited, but is preferably 13 g/m or ^more , more preferably 15 g/m or ^more , and preferably It is 30 g/m ² or less, more preferably 25 g/m ² or less.

At least a part of the exterior body 10 is a composite stretchable portion 10E having stretchability in the horizontal direction Y. In the composite stretchable portion 10E, as shown in FIG. 4 , the outer layer sheet 11 and the inner layer sheet 12 are joined by a plurality of joining portions 13 arranged at intervals in the horizontal direction Y.

The composite expansion-contraction part 10E has the expansion-contraction member which imparts elasticity to the composite expansion-contraction part 10E. In other words, the composite expansion-contraction part 10E is the part in the exterior body 10 in which the expansion-contraction member which has elasticity in the horizontal direction Y is arrange|positioned. There is no particular limitation on the above-mentioned stretchable member, for example, it may be a stretchable sheet, or a string-shaped or belt-shaped elastic member. The composite expansion-contraction part 10E may have the said expansion-contraction member of several types (for example, both expansion-contraction sheet and an elastic member). For example, when at least one of the outer-layer sheet 11 and the inner-layer sheet 12 is an elastic sheet (an elastic member) stretchable in the horizontal direction Y, the arrangement portion of the elastic sheet may be the composite elastic portion 10E. In addition, when a plurality of elastic members (stretchable members) are stretchably fixed in the transverse direction Y between the two sheets 11, 12, even if both of the two sheets 11, 12 are not stretchable sheets, the elastic The arrangement part of the components may be the compound expansion and contraction part 10E.

In the present embodiment, the outer layer sheet 11, more specifically, the abdominal outer layer sheet 11A and the back side outer layer sheet 11C are each composed of a stretchable sheet 20 (see FIG. Unlike this, the inner layer sheet 12 (12A, 12C) is composed of a non-stretchable sheet and does not have stretchability. That is, in the present embodiment, the outer-layer sheet 11 is an elastic member that imparts elasticity to the composite elastic portion 10E, and the inner-layer sheet 12 is not the elastic member. In the exterior body 10, the portion where the outer-layer sheets 11A, 11C, which are stretch sheets, and the inner-layer sheets 12A, 12C, which are non-stretch sheets, are joined via the joint portion 13 has stretchability in the horizontal direction Y as a whole, and is Composite telescopic part 10E. Therefore, in this embodiment, the arrangement part of the outer layer sheets 11A and 11C, that is, the arrangement part of the elastic sheet 20 is the composite elastic part 10E.

When describing the stretchable sheet that can be used as a component of the composite stretchable portion 10E, the stretchable sheet preferably has a maximum elongation in the transverse direction Y of 50% or more, and the stretchable sheet is stretched in the transverse direction Y to an elongation of 100%. Finally, the elongation recovery rate upon shrinkage (that is, the elongation recovery rate upon 100% elongation) is preferably at least 70%.

The stretch sheet has a higher maximum elongation rate in the lateral direction Y than in the longitudinal direction X, and a higher elongation recovery rate. More specifically, the stretch sheet preferably has a maximum elongation of 50% or more and an elongation recovery of 70% or more in the transverse direction Y, shrinks after stretching, and does not shrink after stretching in the longitudinal direction X. The elongation recovery rate of the sheet is measured by the following measurement method.

<Measurement method of elongation recovery rate>

A sample piece with a length of 50 mm and a width of 25 mm was prepared from the piece to be measured (stretchable piece). Fix the sample piece between the chucks (chuck interval K0) of a tensile testing machine ("TENSILON" RTC-1150A of ORIENTEC CO., LTD.) in a non-elongated and non-slack state at a tensile speed of 300mm/ min expand the space between the chucks to pull the sample piece, stretch it to the length K2 (=K0×2) of the 100% elongation of the sample piece, shrink the space between the chucks at the same speed as the stretching speed, and The length of the sample piece when the tensile stress becomes 0 is defined as the length K1 after recovery from elongation. The elongation recovery rate at 100% elongation of the sheet to be measured was calculated by the following formula.

Elongation recovery rate at 100% elongation (%) = [(K2-K1)/(K2-K0)]×100

As a stretchable sheet, for example, it is possible to preferably use: (1) a stretchable non-woven fabric with an extensible fiber layer integrated on both sides or one side of the elastic fiber layer; Stretchable non-woven fabric with extensible fiber layer integrated on the surface; (3) stretchable non-woven fabric with extensible fiber layer integrated on both sides or one side of the elastic sheet made of elastic film; ( 4) A large number of elastic filaments arranged in a manner to extend in one direction without intersecting each other, in a substantially non-elongated state, bonded to an extensible fiber layer throughout its entire length. cloth etc.

The "extensible fiber layer" mentioned here includes not only the fiber layer that can be stretched before being integrated with the elastic material, but also includes the fiber layer that becomes stretchable by machining or the like after being integrated with the elastic material. Stretchable fiber layer.

As a method of integrating the elastic fiber layer and the extensible fiber layer, for example, a method in which they are laminated and entangled by spunlace or hot air, etc., and bonded by heat embossing, adhesives, ultrasonic waves, etc. Methods.

In FIG. 6, the elastic sheet 20 which is an example of an elastic sheet is shown. The stretch sheet 20 corresponds to the stretch nonwoven fabric of (4) above. The stretch sheet 20 includes a fiber layer stretchable in the transverse direction Y, and a plurality of elastic filaments 23 joined to one surface of the fiber layer and extending in the transverse direction Y. In the form shown in FIG. 6 , two opposing fiber sheets 21 , 22 are included as the above-mentioned fiber layer, and a plurality of elastic filaments 23 are arranged between the two fiber sheets 21 , 22 .

The stretch sheet 20 can be manufactured by the method described in Unexamined-Japanese-Patent No. 2009-61743, for example. Specifically, for example, a plurality of elastic filaments 23 in a molten state spun from a spinneret are drawn and stretched at a predetermined speed, and before the solidification of the elastic filaments 23, the elastic filaments 23 do not cross each other. The elastic filaments 23 are welded to the fiber sheets 21, 22 in a manner arranged in one direction, and then the two sheets 21, 22 welded with the elastic filaments 23 are extended along the extending direction of the elastic filaments 23 , and thus the stretch sheet 20 can be manufactured.

The stretch sheet 20 has stretchability in one direction (horizontal direction Y) as a whole. In the stretch sheet 20, the pitch P (refer to FIG. 6 ) of the elastic filaments 23 that impart stretchability in the horizontal direction Y to the stretch sheet 20 is relatively short, and the plurality of elastic filaments 23 are arranged at a relatively high density in the longitudinal direction X. By disposing such elastic filaments 23 , the entire stretch sheet 20 has stretchability in the horizontal direction Y. The pitch P of the elastic filaments 23, that is, the distance P between the centers of any two adjacent elastic filaments 23, 23 in the longitudinal direction X, is preferably 3 mm from the viewpoint of imparting stretchability to the stretch sheet 20 as a whole. or less, more preferably 2 mm or less. The lower limit of the pitch P of the elastic filaments 23 is not particularly limited, but is preferably 0.5 mm or more, more preferably 1 mm or more.

Both of the two fiber sheets 21 and 22 constituting the stretch sheet 20 are expandable in the same direction as the extending direction (horizontal direction Y) of the elastic filaments 23 . The "extensible" mentioned here includes: (a) the case where the constituent fibers of the fiber sheets 21 and 22 are elongated; (b) even if the constituent fibers themselves are not elongated, the fibers bonded at the intersections are separated from each other. , or when the three-dimensional structure formed by the plurality of fibers changes structurally due to the bonding of the fibers, or the fibers are torn, and the fiber sheets 21 and 22 are elongated as a whole.

The elastic filament 23 is a material formed by stretching an elastic resin in a melted or softened state. The plurality of elastic filaments 23 are respectively arranged continuously over the entire length in the horizontal direction Y of the stretch sheet 20 . The plurality of elastic filaments 23 are arranged so as to extend in one direction (horizontal direction Y) without crossing each other. The elastic filaments 23 are joined to the two sheets 21 and 22 in a substantially non-stretched state. The joining of the elastic filaments 23 and the fiber sheets 21, 22 is accomplished by welding the constituent fibers (non-elastic fibers) of the two sheets 21, 22 to the elastic filaments 23 in a state embedded in the elastic filaments 23, instead of using Bonding with adhesives such as hot melt adhesives. Therefore, no adhesive is present between the fiber sheets 21 and 22 (extensible fiber layers mainly composed of inelastic fibers) and the elastic filaments 23 bonded to them.

The stretch sheet 20 is stretchable in the same direction as the direction in which the elastic filaments 23 extend (horizontal direction Y). The stretchability of the stretch sheet 20 is reflected by the elasticity of the elastic filaments 23 . When the stretch sheet 20 is stretched in the same direction as the direction in which the elastic filaments 23 extend, the elastic filaments 23 and the fiber sheets 21 and 22 are stretched. And when the stretching of the stretch sheet 20 is released, the elastic filaments 23 shrink, and the fiber sheets 21 and 22 return to the state before stretching according to the shrinkage. In addition, in the elastic sheet 20, as described in Japanese Patent Application Laid-Open No. 2009-61743, during its manufacture, the fiber sheets 21, 22 are stretched along the direction in which the elastic filaments 23 extend, and the two sheets 21, 22 Since a part of the bonding of the mutual fibers is broken, an "extension allowance" is provided in both sheets 21 and 22 . Specifically, in the fiber sheets 21 and 22 of the stretch sheet 20 manufactured through such a stretching process, as shown in FIG. Since the lower low-density portions 25 are alternately formed in the extending direction of the elastic filaments 23 , in the fiber sheets 21 and 22 , the low-density portions 25 are easily deformed and can follow the expansion and contraction of the elastic filaments 23 . Therefore, when the elastic sheet 20 is stretched in the extending direction (lateral direction Y) of the elastic filaments 23 , the elastic sheet 20 can be stretched so as to hardly contract in the horizontal direction Y, so-called shrinking. Moreover, the change in apparent thickness accompanying expansion and contraction of the elastic sheet 20 is small, and can become a flat sheet even if it expands and contracts. In addition, in the aspect shown in FIG. 9, the elastic sheet 20 is used as the outer-layer sheet 11, and the outer-layer sheet 11 has the above-mentioned characteristics. The details of the form shown in FIG. 9 will be described later.

Each of the two fiber sheets 21 and 22 constituting the stretch sheet 20 can be a nonwoven fabric of short fibers. Examples of the nonwoven fabric include through-air nonwoven fabrics, hot-rolled nonwoven fabrics, spunlace nonwoven fabrics, spunbond nonwoven fabrics, and meltblown nonwoven fabrics. The two sheets 21 and 22 may be of the same kind or different kinds.

The elastic filaments 23 constituting the stretch sheet 20 are made of, for example, a thermoplastic elastomer or rubber. In particular, when a thermoplastic elastomer is used as a raw material, it can be melt-spun using an extruder similarly to ordinary thermoplastic resins, and since the elastic filaments obtained in this way are easily thermally welded, they are suitable for the stretch sheet 20 . Examples of thermoplastic elastomers include SBS (styrene-butadiene-styrene), SIS (styrene-isoprene-styrene), SEBS (styrene-ethylene-butadiene-styrene), Styrene-based elastomers such as SEPS (styrene-ethylene-propylene-styrene), olefin-based elastomers (ethylene-based α-olefin elastomers, propylene-based elastomers obtained by copolymerizing ethylene, butene, octene, etc. body), polyester elastomers, polyurethane elastomers, etc., these can be used alone or in combination of two or more. In addition, core-sheath type or side-by-side type conjugate fibers made of these resins can also be used.

In this embodiment, as mentioned above, the inner layer sheet 12 (12A, 12C) is comprised by a non-stretch sheet. In addition, the crotch outer layer sheet 11B, which is a part of the outer layer sheet 11, is also composed of a non-stretchable sheet. The non-stretchable sheet preferably has an elongation recovery measured by the above-mentioned <Measurement method of elongation recovery> of 20% or less, or ruptures before 100% elongation.

As the non-stretch sheet, non-woven fabrics of various manufacturing methods can be used, for example, spun-bonded non-woven fabrics, air-through non-woven fabrics, needle-punched non-woven fabrics, and the like can be used. The non-stretch sheet (inner layer sheets 12A, 12C, outer layer sheet 11B) may have a single-layer structure, or may have a laminated structure in which two or more sheets (nonwoven fabrics) are stacked, and is typically a single-layer structure.

In this embodiment, in the parts corresponding to the abdominal part A and the back part C (waist area D1, ilium area D2, and hip area D3) in the composite elastic part 10E (outer body 10), the horizontal direction Y A plurality of elastic members 7 for forming waist gathers are arranged so as to be stretchable. The plurality of elastic members 7 are stretchably fixed by an adhesive in the horizontal direction Y between the outer layer sheets 11 (11A, 11C) and the inner layer sheets 12 (12A, 12C) constituting the exterior body 10, and are fixed in the longitudinal direction X. configured at intervals. That is, in the present embodiment, the composite stretchable portion 10E includes not only the stretchable sheet 20 constituting the outer layer sheet 11 but also a stretchable sheet arranged outside the composite stretchable portion 10E so as to be stretchable in the horizontal direction Y as the stretchable member that imparts stretchability to the composite stretchable portion 10E. The elastic member 7 between the ply 11 and the inner ply 12 .

In the natural state or wearing state of the diaper 1, the portions corresponding to the abdominal portion A and the back portion C in the exterior body 10 are formed in a direction intersecting with the contraction direction of the elastic member 7 due to the contraction of the elastic member 7. A plurality of pleats (pleats) extending upward so as to extend over the respective entire circumferences of the abdominal portion A and the dorsal portion C form substantially continuous annular waistline gathers. Moreover, the part of the elastic member 7 which overlaps with the absorber 5 (absorbent main body 2) in planar view was subjected to expansion and contraction preventing treatment such as cutting and heating (see FIG. 3 ).

In addition, in the present embodiment, one or more elastic members 8 for forming leg gathers are disposed on the leg edge portions LS forming the opening edge portions of the pair of leg openings LH, LH, respectively. The elastic member 8 is stretchably fixed between the outer layer sheets 11 ( 11A, 11C) and the inner layer sheets 12 ( 12A, 12C) with an adhesive. In the natural state or wearing state of the diaper 1, by contraction of the elastic member 8, the opening edge portion constituting the leg opening LH in the exterior body 10 is formed in a direction intersecting with the contraction direction of the elastic member 8. A plurality of gathers (gathers) extending upwards form substantially continuous annular leg gathers over the entire circumference of the opening edge portion of the leg opening LH.

As materials for various elastic members in the diaper 1 represented by the elastic members 7 and 8, various known elastic materials generally used in such absorbent articles can be used without particular limitation unless otherwise specified. For example, synthetic rubbers such as styrene-butadiene, butadiene, isoprene, and chloroprene, natural rubber, EVA, stretchable polyolefin, polyurethane, and the like can be exemplified. As the form of the elastic member, it is preferable to use a filament-shaped (silk rubber, etc.) or belt-shaped (rubber strip, etc.) elastic member with a rectangular, square, circular, polygonal cross-section, or a multi-filament linear elastic member. parts etc.

At least one of the abdominal portion A and the back portion C is provided with an outer body folded portion 14 including a portion folded back so that the inner layer sheet 12 is inside. In the present embodiment, as shown in FIGS. 2 and 5 , exterior body folding portions 14 are provided on both the abdominal portion A and the back portion C. As shown in FIG. FIG. 7 shows a cross section along the transverse direction Y of the folded-back portion 14 of the abdominal portion A, and a perspective view of the folded-back portion 14 viewed from the outer surface side 14 a is shown in FIG. 8 . 7 and 8 schematically show the natural state of the diaper 1 (the state in which no external force is applied to the diaper 1), that is, the outer body when the elastic members and elastic members such as the elastic members of the outer body 10 are in a non-extended state. The state of the folded part 14. Hereinafter, the exterior body folded portion 14 of the abdominal portion A will be described as an example, and such description is also applicable to the exterior body folded portion 14 of the back portion C unless otherwise specified.

The exterior body folding portion 14 is a portion formed by folding back a composite stretchable portion 10E of a two-layer structure including the outer layer sheet 11 (11A, 11C) and the inner layer sheet 12 (12A, 12C), and includes four layers including four sheets. structure. The outer body folded portion 14 is divided into: the outer surface side 14a that is located on the outer side in the thickness direction than the folded line of the folded back of the composite stretchable portion 10E and forms the outer surface (non-skin-facing surface) of the diaper 1; The inner surface side 14b which forms the inner surface (skin facing surface) of the diaper 1 is located on the inner side in the thickness direction rather than this bending line of 10E of composite expansion-contraction parts.

In this embodiment, the outer layer sheet 11 and the inner layer sheet 12 respectively have extensions extending from the longitudinal end 5E of the absorber 5 to the outside in the longitudinal direction X, and the extensions of the two sheets 11, 12 make the inner layer The sheets 12A and 12C are folded back inside to form the exterior body folded portion 14 . The longitudinal end 1E of the diaper 1 coincides with the folding line of the exterior body 10 at the folded back. Therefore, in this embodiment, the exterior body folded part 14 is arrange|positioned at least in the edge part of the longitudinal direction X of the diaper 1, ie, the waist region D1.

In the present invention, the exterior body folded portion 14 may be arranged not only in the waist region D1 but also in the ilium region D2 and the hip region D3.

In this embodiment, the length of the longitudinal direction X of the part of the inner-layer sheet 12 located in the inner surface side 14b is longer than that of the outer-layer sheet 11 .

In the present invention, the size relationship between the lengths of the two pieces 11 and 12 on the inner surface side 14b of the outer body folded portion 14 is not particularly limited, and the outer layer sheet 11 may be longer than the inner layer sheet 12 contrary to the illustration. , or the two pieces 11, 12 may be the same length.

In this embodiment, the composite expansion-contraction part 10E, that is, the arrangement|positioning part of the expansion-contraction sheet 20 in the exterior body 10 has all the structures of following (1)-(3).

(1) The outer-layer sheets 11 (11A, 11C) and the inner-layer sheets 12 (12A, 12C) have a configuration in which they are joined by a plurality of joining portions 13 arranged at intervals in both the longitudinal direction X and the transverse direction Y (refer to Figure 4 and Figure 8).

(2) The outer layer sheets 11 ( 11A, 11C) are composed of stretchable sheets 20 (see FIG. 6 ) that are stretchable in the horizontal direction Y, and the inner layer sheets 12 ( 12A, 12C) are composed of non-stretchable sheets.

(3) Between the outer layer sheet 11 (11A, 11C) and the inner layer sheet 12 (12A, 12C), a plurality of elastic members 7 extending in the horizontal direction Y are arranged at intervals in the longitudinal direction X, and each elastic member 7 is It is fixed elongately in the transverse direction Y without means of the joint 13 . In other words, a plurality of engaging portions 13 are arranged at intervals in a row in the transverse direction Y, and a plurality of engaging portions 13 extending in the transverse direction Y are arranged at intervals in a longitudinal direction X. The rows of engaging portions 13 and the elastic The members 7 are alternately arranged in the longitudinal direction X (see FIG. 5 and FIG. 8 ). The elastic member 7 is bonded to the two sheets 11, 12 with an adhesive.

In the composite stretchable part 10E in a natural state, as shown in FIGS. Between the concave strips 120, the convex strips 121 having the bent portion 12P of the inner layer sheet 12 as the top are formed. The protruding part 121 is a part of the non-forming part of the junction part 13 located in the inner layer sheet 12, and is a part protruding to the side opposite to the outer layer sheet 11. The protruding part 121 is hollow, that is, in the protruding part 121. A space is formed between the outer layer sheet 11 and the inner layer sheet 12 .

On the other hand, in the composite stretchable portion 10E in a natural state, the outer layer sheet 11 (the stretchable sheet 20 ) as shown in FIG. There are a plurality of bent portions 11P in a region where one convex portion 121 overlaps. That is, in the composite stretchable portion 10E in a natural state, the number of bent portions per unit length in the transverse direction Y is greater in the outer layer sheet 11 (stretchable sheet 20 ) than in the inner layer sheet 12 (non-stretchable sheet). That is, in the composite stretchable portion 10E in a natural state, the outer layer sheet 11 also has a wrinkled structure similar to the inner layer sheet 12, which consists of a plurality of grooves extending in the longitudinal direction X, and the grooves located between the grooves. The curved portion 11P of the outer layer sheet 11 is configured as a convex portion at the top, and the pitch (interval) of the convex or concave portions in the outer layer sheet 11 is shorter than the pitch (interval) in the inner layer sheet 12 .

In the composite elastic portion 10E in a natural state, as one of the reasons why the outer layer sheet 11 is deformed so as to bend at the plurality of bending portions 11P formed at intervals in the horizontal direction Y in this way is that the elastic sheet forming the outer layer sheet 11 is 20 alternately has "two types of sites different in shape or physical properties" in the horizontal direction Y.

In the present embodiment, as described above, the elastic sheet 20 is stretched in the direction in which the elastic filaments 23 extend (transverse direction Y) during the manufacturing process, and the fibers constituting the elastic sheet 20 are stretched through the stretching process. In the sheets 21 and 22, as enlargedly shown in FIG. 9 , high-density portions 24 having a relatively high density of the constituent fibers and relatively high density portions of the constituent fibers are alternately formed in the direction of extension of the elastic filaments 23 (transverse direction Y). In the low-density portion 25, it is considered that such a difference in fiber density promotes bending deformation of the stretch sheet 20 (outer layer sheet 11). In the natural state of the stretch sheet 20, typically, as shown in FIG. 9 , the high-density portion 24 serves as a bending starting point to form a bent portion 11P, and the low-density portion 25 is located between two adjacent bent portions 11P, 11P. In addition, in the enlarged view of the part enclosed by the dotted line in FIG. 9 , from the viewpoint of easy understanding, only the fiber sheets 21 and 22 are described as the constituent members of the stretch sheet 20, and the elastic filaments 23 are not described. In fact, the elastic The filaments 23 are arranged between the fiber sheets 21 and 22 to be integrated.

As the "shape or physical properties" in the above-mentioned "two types of positions different in shape or physical properties" that can promote the bending deformation of the outer layer sheet 11 (stretch sheet 20), in addition to the above-mentioned "fiber density", for example, rigidity can be exemplified. , distance between fibers, gram weight, presence or absence of stretching treatment, number of fiber ends, flatness, etc.

The composite stretchable part 10E is typically formed by joining the elastic member 7 to the non-stretchable inner layer sheet 12 in a state stretched in the transverse direction Y, and stretching the outer layer sheet 11 (stretchable sheet 20 ) in the transverse direction Y direction. The long state is produced by releasing the elastic member (the elastic member 7 and the outer layer sheet 11 ) from the stretched state to a natural state after joining the joint portion 13 . In the natural state of the composite stretchable portion 10E produced in this way, the stretchable member shrinks in the horizontal direction Y, and the inner layer sheet 12 is deformed in a curved manner between the joint portions 13, 13 adjacent in the horizontal direction Y. In the rear inner-layer sheet 12 , the convex lines 121 having the bent portion 12P as the top and the concave lines 120 having the joining portion 13 at the bottom are alternately arranged in the horizontal direction Y. On the other hand, the outer layer sheet 11 composed of the elastic sheet 20 is deformed so as to be bent by the plurality of bent portions 11P formed at intervals in the transverse direction Y similarly to the inner layer sheet 12, but the uneven pitch is smaller than that of the inner layer sheet. The concave-convex pitch in 12 is short, and in addition, because the height of the protruding line part 121 of outer layer sheet 11 is lower than the height of the convex line part 121 of inner layer sheet 12 (the depth of the concave line part of outer layer sheet 11 is lower than the concave line of inner layer sheet 12 The depth of the portion 120 is shallow), so the outer layer sheet 11 can be regarded as a flat sheet without unevenness depending on the situation.

Since the exterior body folded portion 14 thus has a laminated structure formed by folding back the complex elastic portion 10E having a concavo-convex structure in a natural state, it is excellent in cushioning and air permeability. In addition, the surface of the outer body folded portion 14 of the diaper 1 that is in contact with the wearer's skin is formed of the outer layer sheet 11 with relatively small unevenness, and is typically substantially flat so that it does not affect the wearer's skin. The burden on the skin is small, and it is not easy to cause pressure marks on the skin even for wearers who mostly sleep. Since the diaper 1 is composed of the exterior body 10 including the exterior body folded portion 14 having such a feature, it is less likely to cause pressure marks on the skin of the wearer who is often in a sleeping position, and is less likely to be stuffy.

In the composite stretchable part 10E in the natural state, in the outer layer sheet 11 (the stretchable sheet 20), the area overlapping with one convex line part 121 in plan view (the two joining parts 13, 13 adjacent in the horizontal direction Y) between) the number of bends 11P (the total number of bends on one side of the outer layer sheet 11 and the number of bends on the other side) depends on the combined expansion and contraction of the outer layer sheet 11 as a representative. The type or basic weight of the constituent parts of the portion 10E, the elongation characteristics of the elastic sheet 20 and the elastic member 7, etc., but from the viewpoint of making the function and effect of the folded-back portion 14 of the exterior body more reliably exhibited, preferably two or more , more preferably 3 or more. The upper limit of the number of bent portions 11P is not particularly limited, but is preferably 10 or less, more preferably 5 or less, from the viewpoint of preventing the strength of the stretch sheet 20 from decreasing with the increase of the low-density portion 25 .

The length (width) of one rib portion 121 in the transverse direction Y, that is, the distance between two adjacent joining portions 13, 13 in the transverse direction Y, is preferably 2 mm or more, more preferably 3 mm or more, and preferably 15 mm or less. More preferably, it is 10 mm or less.

The above-mentioned "the number of bent portions 11P in the outer layer sheet 11" is observed with a microscope at an arbitrary magnification through, for example, a cross-section of the outer layer sheet 11 along the thickness direction in the stretching direction. In the process of changing from the long state to the state of natural length (non-extended state), the area overlapping with one rib portion 121 in plan view (between the two adjacent joint portions 13, 13 in the horizontal direction Y) It can be measured by visually counting the number of bent portions 11P formed in . Hereinafter, this measurement method is also referred to as "measurement method A". In the above measurement method A, the apparent thickness of the bent portion 11P to be counted in the outer layer sheet 11 is twice or more than the thickness of the outer layer sheet 11 in an elongated state (a state in which the bent portion 11P is not substantially formed). In this case, the height of the ridge portion of the outer layer sheet 11 with the curved portion 11P as the apex is the same as or higher than the height of the ridge portion 121 of the inner layer sheet 12 overlapping the ridge portion in plan view. The height of the portion 121 is low.

The measurement method A described above is difficult to apply when the bending portion 11P has a relatively small size and is difficult to recognize visually. For example, when the outer layer sheet 11 is a stretch sheet 20 manufactured by the method described in Japanese Patent Application Laid-Open No. 2009-61743 with stretching treatment, the curved portion 11P tends to become finer, and the curved portion 11P is measured by the measurement method A. The number of parts 11P is difficult in many cases. In such a case, by cutting out the composite telescopic part 10E from the exterior body 10 (the part of the exterior body 10 where the telescopic member having stretchability in the horizontal direction Y is arranged), the cut out composite telescopic part 10E becomes an extensible In the long state, the method of counting the number of high-density parts 24 and low-density parts 25 (hereinafter also referred to as "measurement method B") can measure the above-mentioned "number of curved parts 11P in the outer layer sheet 11". ". That is, with reference to Fig. 9, since the curved portion 11P is formed by the expansion and contraction of the elastic filament 23, the high-density portion 24 is not deformed and the low-density portion 25 is deformed, so compared to “two low-density portions 25 and one high-density portion 24" or "a combination of one low-density part 25 and two high-density parts 24" to form the convex or concave part of one outer layer sheet 11 (stretchable sheet 20). Therefore, in the above-mentioned measurement method B, the outer layer sheet 11 (stretchable sheet 20) in the stretched state is observed, and the numbers of the high-density portion 24 and the low-density portion 25 in this state are counted respectively, based on the counted number and The number of joined portions 13 can be calculated from the aforementioned “number of bent portions 11P in the outer layer sheet 11 ”.

When compressing the composite stretchable portion 10E (external folded portion 14 ) in the thickness direction, specifically, for example, when compressing the composite stretchable portion 10E in the thickness direction with a load of 3 kPa, the outer layer sheet is preferably 11 (stretch sheet 20) has a higher rate of reduction in thickness than the inner layer sheet 12. The thickness reduction rate was calculated by the following formula.

Thickness reduction rate (%)={(thickness of sheet before compression-thickness of sheet in compressed state)/thickness of sheet before compression}×100

The outer layer sheet 11 (stretch sheet 20) forms the surface of the outer body folded portion 14, and is a part that will come into contact with the skin of the wearer of the diaper 1. The reduction rate of the thickness of the outer layer sheet 1 is higher than that of the inner layer sheet 12, that is, the outer layer sheet 11 The ply sheet 11 is easy to be compressed and deformed, and when compressed with a constant load, tends to become flat, so that it is difficult to form an indentation on the skin of the wearer of the diaper 1 . On the other hand, since the reduction rate of the thickness of the inner-layer sheet 12 is lower than that of the outer-layer sheet 11, the shape of the protruding line 121 formed in a natural state is easily maintained, and the outer body folding portion 14 (composite shape) can be further improved. Cushioning and breathability of the elastic portion 10E).

Such a magnitude relationship of "the reduction rate of the thickness of the outer layer sheet 11>the reduction rate of the thickness of the inner layer sheet 12" can be established by configuring the outer layer sheet 11 and the inner layer sheet 12 as described in this specification.

The bonding portion 13 may also be formed by using an adhesive such as a hot melt adhesive, that is, even if the two sheets 11, 12 are bonded to each other by an adhesive, but in this embodiment, the bonding portion 13 is formed by the two sheets 11, 12, 12 welds are formed. When the joining part 13 is formed with an adhesive, there is a concern about the adhesive bleeding out, but forming it with a welded part eliminates such a concern and further reduces the burden on the skin of the wearer of the diaper 1 .

In the joining portion 13 constituted by the welded portion of the two sheets 11, 12, the two sheets 11, 12 are formed into a film shape or a form based thereon. Formation of the joining portion 13 by welding the two sheets 11 and 12 can be performed by a known resin sheet welding method such as embossing with heat, ultrasonic sealing, or the like.

The joint portion 13 preferably extends in the longitudinal direction X, as shown in FIG. 8 . According to such a structure, the cushioning property of the exterior body folded part 14 improves further, For example, when the wearer of the diaper 1 is in a sleeping position etc., and load is applied to the exterior body folded part 14, a favorable cushioning feeling can be acquired. The term "extending in the longitudinal direction X" includes: 1) a plurality of joints 13 arranged at intervals in the longitudinal direction X to form a row of joints 13 extending in the longitudinal direction X (see FIG. 8 ); and 2) A form (not shown) in which the joining portion 13 has a continuous linear shape (straight, curved, etc.) in plan view. In the form of 1) above, the plan view shape of the joining portion 13 is not particularly limited, and may be, for example, a circular shape, an elliptical shape, a triangular shape, or a quadrangular shape other than the quadrangular shape as shown in the figure. In the case of the form of 2) above, the elastic member 7 can intersect with the continuous linear joint portion 13 .

In the present embodiment, in the composite stretchable part 10E in the natural state, the protruding part 121 constituting the wrinkle structure of the inner layer sheet 12 is hollow as shown in FIGS. The hollow structure of the strip portion 121 largely contributes to the improvement of cushioning and air permeability of the exterior body folded portion 14 . It is preferable that the inner-layer sheet 12 has higher rigidity than the outer-layer sheet 11 (stretch sheet 20 ) from the viewpoint of stably maintaining the hollow structure of the ridge part 121 during wearing of the diaper 1 .

The rigidity of the sheets constituting the composite expandable portion 10E (exterior body 10 ) was measured by the following method.

<Measuring method of rigidity>

From the sheet to be measured, specifically, for example, the outer layer sheet 11 (stretchable sheet 20) or the inner layer sheet 12, the length in the stretching direction (horizontal direction Y of the absorbent article) of the composite stretchable portion 10E including the sheet is cut out as follows: 150 mm, the length of the direction (longitudinal direction X of an absorbent article) perpendicular|vertical to this expansion-contraction direction is 30 mm, and the test piece of planar view rectangular shape. In addition, the above-mentioned expansion and contraction direction typically coincides with the flow direction (machine direction MD) at the time of production of the sheet. When taking out the sheet to be measured from the absorbent article (composite stretchable part), if the sheet to be measured is bonded to other parts, use heating equipment such as a dryer or cold spray, organic solvent, etc. to dry the sheet to be measured After invalidating the joint with other parts, the piece of measurement object is carefully peeled off from other parts.

The above-mentioned test piece was rolled up so that the longitudinal direction of the test piece became the circumferential direction, and both ends in the longitudinal direction of the test piece were overlapped by 5 mm to form a cylinder with a diameter of 45 mm. Then, at the overlapped part of both ends, fix the upper end and the lower end of the axial direction of the cylinder with a staple such as a No. 10-1M needle manufactured by MaxCo., Ltd., and make a measurement of the cylindrical shape. sample. However, the direction of the staples is parallel to the circumferential direction. Each of the prepared cylindrical measurement samples was erected so that the respective axial directions coincided with the vertical direction, and placed in a compression testing machine such as "RTA-100" manufactured by Orientec Co., Ltd. Company. And, use a circular compression plate with a diameter of 70mm or more to compress the measurement sample at a compression speed of 10mm/min in the axial direction of the cylinder, and record the maximum load (N/30mm) displayed during the compression. Five measurement samples were prepared for one type of sheet to be measured, their respective maximum loads were measured, and the arithmetic mean value thereof was taken as the rigidity value of the sheet to be measured.

The ratio of the rigidity of the inner layer sheet 12 to the rigidity of the outer layer sheet 11 (stretchable sheet 20) is based on the premise that the former>the latter, and the ratio of the former/the latter is 1.1 or more, more preferably 1.2 or more, and preferably 3.0 or less , more preferably 2.0 or less.

The rigidity of the outer layer sheet 11 (stretch sheet 20 ) is premised to be lower than the rigidity of the inner layer sheet 12, and is preferably 10.0 N or less, more preferably 8.0 N or less.

Rigidity of the inner-layer sheet 12 is assumed to be higher than that of the outer-layer sheet 11 (stretch sheet 20 ), and is preferably 16.0 N or less, more preferably 15.0 N or less.

In this embodiment, as described above, in the composite stretchable portion 10E, as the stretchable member that imparts stretchability to the composite stretchable portion 10E as shown in FIG. 8 and FIG. There is also an elastic member 7 that is stretchably arranged in the transverse direction Y between the outer layer sheet 11 and the inner layer sheet 12, and the elastic member 7 helps the hollow structure of the rib portion 121 to be more stable when the diaper 1 is worn. Maintaining and further contributing to the further improvement of the cushioning and air permeability of the exterior body folded portion 14 . That is, during wearing of the diaper 1, a part of the outer layer sheet 11 penetrates into the hollow portion of the rib portion 121 in the inner layer sheet 12, whereby the rib portion 121 does not become a hollow structure substantially, which may cause However, in this embodiment, the elastic member 7 is arranged between the two sheets 11 and 12, so that the outer layer sheet 11 can be suppressed from falling into the hollow portion of the rib portion 121. The intrusion can eliminate such worries.

From the viewpoint of being able to reliably exert the effect of improving the stability of the hollow structure of the rib portion 121 produced by such an elastic member 7, and preventing excessive restraint of the wearer by an excessive number of elastic members 7, adjacent in the longitudinal direction X The distance 7P (see FIG. 8 ) between the elastic members 7 and 7 is preferably 4 mm or more, more preferably 5 mm or more, and is preferably 10 mm or less, more preferably 8 mm or less.

In order to reliably exhibit the prescribed effects of the present invention, especially the effect of the exterior body foldback 14 , it is preferable that the plurality of ribs 121 of the exterior body foldback 14 also extend along the longitudinal direction X and maintain its hollow structure. As one of the factors affecting the formation of the protruding line portion 121 , the expansion and contraction characteristics of the composite expansion and contraction portion 10E (elongation magnification of the expansion and contraction member, elongation stress, etc.) can be exemplified. In addition, since the expansion and contraction characteristics of the composite stretchable portion 10E are affected by the absorber 5 overlapping it in plan view, the arrangement of the absorber 5 and the like must also be taken into account in order to stably present the ridge portion 121 in a desired form.

Regarding this point, in this embodiment, as shown in FIGS. 2 and 5 , in each of the abdominal portion A and the back portion C, the longitudinal end 5E of the absorber 5 is located closer to the longitudinal direction X than the longitudinal end 1E of the diaper 1 . When the area sandwiched between the two longitudinal ends 5E, 1E becomes the absorber non-arrangement region 5N, it is preferable that, in the composite stretchable portion 10E, the portion located in the absorber non-arrangement region 5N be the same as the one located at and The expansion ratio of the stretchable member that imparts stretchability to the composite stretchable portion 10E is lower in the absorber non-arrangement region 5N adjacent to the absorber arrangement region in the longitudinal direction X than in the absorber non-arrangement region 5N.

The above-mentioned "absorbent body arrangement area" refers to the area where one imaginary straight line (not shown) crossing the abdominal portion A or the back portion C in the horizontal direction Y is drawn, and the imaginary straight line overlaps with the absorbent body 5. In other words, the region is a region in which the projected image of the absorber 5 in the horizontal direction Y can be formed in the abdominal part A or the back part C. In the present embodiment, the regions other than the absorber non-arrangement region 5N in each of the abdominal part A and the back part C are the above-mentioned absorber arrangement regions.

The absorber non-arrangement region 5N is more likely to be affected by stretchable members than the absorber arrangement region because the absorber 5 with relatively high rigidity is not arranged. Therefore, due to the expansion and contraction properties of the expansion and contraction members of the composite expansion and contraction portion 10E, the extending direction of the rib portion 121 in the absorbent body non-arrangement region 5N may become non-parallel to the longitudinal direction X and become a direction intersecting with the longitudinal direction X. 1. The shape of the protruding line part 121 is collapsed and the hollow structure cannot be maintained. On the other hand, as described above, with respect to the expansion ratio of the stretchable member of the composite stretchable portion 10E, by establishing the size relationship of "absorber non-arrangement region 5N<absorber arrangement region", the occurrence of this problem can be prevented, and the occurrence of this problem can be prevented. The prescribed effect of the present invention can be exhibited more reliably.

The above-mentioned "strength ratio" is an indicator of the degree of tension of the stretchable components (elastic components, stretch sheets, etc.) of the composite stretchable part 10E, and the length of the stretchable component in its natural state (non-stretched state) is set to 100, which is Indicates the value in % of elongation. The elongation ratio is measured by the following method.

First, make the absorbent article (for example, diaper 1) including the elastic member (for example, elastic member 7) to be measured in a state of maximum extension in the direction of expansion and contraction of the elastic member (for example, the horizontal direction Y), and use an oil-based pen to adjust the expansion and contraction. Two marks are marked on the member with a certain interval L0 (eg: 100mm) apart in the expansion and contraction direction. In addition, when the elastic member is covered by a sheet such as nonwoven fabric, it is sufficient to mark the elastic member with an oil-based pen through the sheet. By marking in this way, the ink of the oil-based pen is transferred to the elastic member through the sheet, and the Stamps are marked on the telescopic parts. Next, a portion sandwiched between the two marks is cut out from the stretchable member, and the length L1 in the natural state (non-stretched state) of the cut out stretchable member is measured. And, the elongation ratio was obtained by the following formula [1].

Elongation ratio (%)=(L0/L1)×l00...〔1〕

In this embodiment, when the composite stretchable part 10E has the outer layer sheet 11 (the stretchable sheet 20 ) and the elastic member 7 as the stretchable member as described above, when the composite stretchable part 10E has a plurality of types of stretchable members like this, The above-mentioned magnitude relationship may be established for some of the expansion ratios of the plurality of types of elastic members, or may be established for all the expansion ratios of the plurality of types of elastic members. In particular, since the expansion and contraction characteristics of the elastic member 7 have a large influence on the formation of the protruding line portion 121, at least the elongation magnification of the elastic member 7 is made to satisfy the above-mentioned size relationship.

From the viewpoint of making the effects of the above-mentioned establishment of the relationship between the magnitudes of the expansion ratios of the stretchable members of the composite stretchable part 10E more reliable, the portion of the composite stretchable part 10E located in the absorber non-arrangement region 5N is combined with the composite stretchable part 10E. It is preferable that the elongation stress is lower than the part located in the said absorber arrangement|positioning area in the expansion-contraction part 10E.

The above "elongation stress" is the load required to elongate the part of the composite stretchable part 10E by a certain length along its stretching direction (transverse direction Y). The larger the value of the elongation stress, the harder it is for the part to elongate. The elongation stress is measured by the following method.

The elongation stress of the composite telescopic part 10E can be adjusted, for example, by appropriately adjusting the type of the telescopic member (expandable sheet, elastic member, etc.) and the arrangement of the telescopic part included in the composite telescopic part 10E. If the telescopic part is an elastic part, it can It is adjusted by appropriately adjusting the number of arrangements, arrangement intervals, thickness of elastic parts, and the like.

In this embodiment, as shown in FIGS. 2 and 5 , the absorber non-arrangement region 5N includes the waist region D1 corresponding to the wearer's waist circumference, and the absorber arrangement region includes the area from the iliac crest to the anterior superior iliac spine of the wearer. The part corresponding to the ilium area D2 also includes the hip area D3.

With regard to the magnitude relationship of the expansion ratio of the stretchable member of the composite stretchable part 10E and the magnitude relation of the stretch stress of the composite stretchable part 10E, it is preferable that Include at least the ilium area D2. That is, with respect to each of the aforementioned elongation magnification and elongation stress, it is preferable that the magnitude relationship of "waist region D1 (absorbent body non-arranged region 5N)<ilium region D2" be established.

<Measurement method of elongation stress>

A case where the underpants-type absorbent article to be measured is the above-mentioned diaper 1 will be described as an example. First, the outer casings 10 bonded at the side joints S are peeled off, the diaper 1 is unfolded and expanded into a planar shape, and the measurement target regions (in the composite stretchable part 10E) are cut out along a straight line parallel to the transverse direction Y of the diaper 1. The portion located in the absorbent body non-arrangement region 5N, the ilium region D2, etc.) was used as a measurement sample. At the time of this cutting, not only the composite elastic part 10E (exterior body 10), but the whole diaper 1 including the absorptive main body 2 etc. are cut. In addition, when there is an elastic member such as the elastic member 7 in the measurement target region, which imparts elasticity to the composite elastic part or a member treated as an elastic member (hereinafter also referred to as "elastic member or the like"), the The measurement sample cut out from the measurement target area includes at least one elastic member or the like in the longitudinal direction X (direction perpendicular to the extending direction of the elastic member or the like) of the measurement sample.

Clamp both ends of the measurement sample in the longitudinal direction (horizontal direction Y) (side joint S or its vicinity) on the chuck of the TENSILON universal testing machine (RTC-1210A) manufactured by ORIENTEC Co., Ltd., and make the measurement sample at a distance of 300mm/ The speed of min is elongated in the longitudinal direction, and the stress (elongation stress) of the measurement sample at this time is measured. Specifically, the inner dimension of the composite stretchable part 10E, more specifically, the distance between the pair of side seal parts S and S in the state where the sheets 11 and 12 constituting the composite stretchable part 10E are not contracted by the elastic member 7 When the length is 100 (for example, 350 mm), the measurement sample is stretched to a length corresponding to 80 (for example, 280 mm), and then shrunk to a length equivalent to 71 (for example, 250 mm), and the tensile load (cN ) as the elongation stress of the measurement sample. The elongation stress of the measurement sample is calculated as the average elongation stress per unit length in the direction (longitudinal direction X) perpendicular to the stretching direction (length direction of the measurement sample) of the measurement object region.

As mentioned above, the reason why the restoring force at a length corresponding to 71 when the inner dimension of the exterior body is taken as 100 is defined as the stress of the measurement sample is that the main infants who wear shorts-type absorbent articles such as diaper 1 The ratio of the length of the abdominal circumference to the inside size of the diaper is about 71%. The length of the abdominal circumference mentioned here is the average value of the abdominal circumference measured in the standing position and the sitting position in consideration of the change in the circumference of the abdominal circumference when the infant's posture changes.

The expansion ratio of the elastic member (elastic member 7 or outer layer sheet 11) in the portion of the composite stretchable portion 10E located in the absorber non-arrangement region 5N (waist region D1), and the portion of the composite stretchable portion 10E positioned in the absorber arrangement The ratio of the elongation magnification of the telescopic member in the region (ilium region D2) is based on the premise that the former < the latter as described above, and the ratio of the former/the latter is preferably 0.3 or more, more preferably 0.5 or more, and , preferably 0.9 or less, more preferably 0.8 or less.

The expansion magnification of the elastic member in the portion of the composite stretchable portion 10E located in the absorber non-arrangement region 5N (waist region D1) is the same as the portion of the composite expandable portion 10E located in the above-mentioned absorber arrangement region (ilium region D2) The elongation ratio of the elastic member is relatively low, preferably 150% or more, more preferably 200% or more, and preferably 300% or less, more preferably 250% or less.

The elongation ratio of the elastic member in the part of the composite elastic part 10E located in the above-mentioned absorber arrangement area (ilium region D2) is the same as that in the part of the composite elastic part 10E located in the absorber non-arrangement area 5N (waist area D1) The elongation ratio of the elastic member is relatively high, preferably 200% or more, more preferably 250% or more, and preferably 400% or less, more preferably 350% or less.

The elongation stress of the part located in the absorber non-arrangement region 5N (waist region D1) in the composite elastic part 10E, and the elongation stress of the part located in the above-mentioned absorber arrangement region (ilium region D2) in the composite elastic part 10E The ratio of is preferably 0.3 or more, more preferably 0.5 or more, and preferably 0.9 or less, more preferably 0.8 or less on the premise that the former < the latter as described above.

The elongation stress of the part located in the absorber non-arrangement region 5N (waist region D1) in the composite elastic part 10E is the same as the elongation stress of the part located in the above-mentioned absorber arranged region (ilium region D2) in the composite elastic part 10E On the premise that the stress is relatively low, it is preferably 0.01 N/mm or more, more preferably 0.02 N/mm or more, and is preferably 0.1 N/mm or less, more preferably 0.05 N/mm or less.

The elongation stress of the portion located in the above-mentioned absorber placement region (ilium region D2) in the composite stretchable portion 10E is the same as the elongation stress of the portion of the composite stretchable portion 10E located in the absorber non-placement region 5N (waist region D1). On the premise that the stress is relatively high, it is preferably 0.02 N/mm or more, more preferably 0.04 N/mm or more, and is preferably 0.2 N/mm or less, more preferably 0.1 N/mm or less.

In the exterior body folding portion 14, as shown in FIG. 7 and FIG. The grooved portion 120 of the surface side 14b (the folded composite stretchable portion 10E located on the inner side in the thickness direction of the exterior body folded portion 14 ) faces each other. According to this configuration, the cushioning performance of the exterior body folded portion 14 is further improved. For example, when a load is applied to the exterior body folded portion 14 when the wearer of the diaper 1 is in a sleeping position, a good cushioning feeling can be obtained.

From the same point of view, in the exterior body folding portion 14, as shown in FIG. 7 and FIG. The strip portion 121 faces the convex strip portion 121 on the inner surface side 14b (the folded composite stretchable portion 10E located on the inner side in the thickness direction of the exterior body folded portion 14 ).

And, as shown in the figure, in the folded-back portion 14 of the exterior body, it is preferable that the rib portion 121 on the outer surface side 14a (one of the opposite composite telescopic portions 10E, 10E) and the inner surface side 14b (the opposite composite telescopic portion The other one of 10E and 10E is bonded to the protruding line portion 121 of the folded composite stretchable portion 10E). In the illustrated form, the tops (curved portions 12P) of both convex line portions 121 are joined to each other via the adhesive portion 15 . Adhesive portion 15 is formed by applying an adhesive such as a hot-melt adhesive.

It is preferable that the adhesive part 15 extends in the longitudinal direction X from the viewpoint of further improving the cushioning properties of the exterior body folded part 14 . The term "extending in the longitudinal direction X" includes: 1) a plurality of bonding portions 15 arranged at intervals in the longitudinal direction X to form a row of bonding portions 15 extending in the longitudinal direction X; and 2) The bonding portion 15 has a form of a continuous line (straight line, curved line, etc.) in plan view.

FIG. 10 shows an exterior body folding portion 14A that is another embodiment of the exterior body folding portion of the present invention. About 14 A of exterior body folding parts, the structure different from the above-mentioned exterior body folding part 14 (refer FIG. 7) is mainly demonstrated, and the same code|symbol is attached|subjected to the same structure, and description is abbreviate|omitted. There is no particular configuration described about the exterior body fold-back portion 14A, and the description about the exterior body fold-back portion 14 can be appropriately used.

In the exterior body folding portion 14A, the composite elastic portion 10E on the outer surface side 14a (the composite elastic portion 10E located on the outer side in the thickness direction of the exterior body folding portion 14A) and the inner surface side 14b (the composite elastic portion 10E located on the outer side of the exterior body folding portion 14A) In the folded composite stretchable portion 10E) on the inner side in the thickness direction, the pattern of the protruding line portion 121 is different. The "pattern of the ridges 121" referred to here includes the pitch of the ridges 121 (the distance between the tops of the ridges 121 and 121 adjacent in the horizontal direction Y), the distance between the tops of the ridges 121, The concept of the width (the length in the direction (horizontal direction Y) perpendicular to the extending direction (longitudinal direction X) of the protruding part 121) and the height of the protruding part 121 is even one of the three on the outer surface side 14a and the inner surface side 14b. If one of them is different, the patterns of the convex lines 121 are different between the outer surface side 14a and the inner surface side 14b.

In 14A of exterior body folding parts, with respect to the two ribs 121 adjacent to the lateral direction Y on the outer surface side 14a, there are three ribs 121 on the inner surface side 14b, and the ribs on the inner surface side 14b 121 has a shorter width. In addition, the height of the convex line part 121 on the inner surface side 14b is low. In the folded-back portion 14A of the exterior body, the inner surface side 14b, which is the portion that comes into contact with the skin of the wearer of the underpants-type absorbent article, has a smaller convex line portion 121 than the outer surface side 14a. Usually, the convex line The smaller the portion 121 is, the easier it is for the complex stretchable portion 10E to become flatter, so the inner surface side 14b can contact the wearer's skin in a flat state with less unevenness. Thereby, it is possible to suppress friction of the wearer's skin by the exterior body folded-back portion 14A, and reduce skin troubles caused thereby.

In addition, the present invention includes an aspect in which the inner surface side 14b is larger than the outer surface side 14a in contrast to the outer body folded portion 14A. As an advantage of such an aspect, it is possible to exemplify that it is smaller than the wearer's skin. The air permeability of the near inner surface side 14b improves this.

The pattern (pitch, width, height) of the protruding line portion 121 is determined by the type and arrangement of the stretchable members (elastic sheet, elastic member, etc.) included in the composite stretchable portion 10E, and the overlapping sheets 12 and 13 constituting the composite stretchable portion 10E. The pattern of the joint part 13 (interval between joint parts, the length of the transverse direction Y of the joint part) and the like are determined. Therefore, by making these factors different on the outer surface side 14a and the inner surface side 14b, the convex lines of both can be made The patterns of the portions 121 are different from each other.

The pants-type absorbent article of the present invention is applicable not only to disposable diapers, but also to disposable pants, pants-type sanitary napkins, etc., which have a pants-shaped structure. Can be an item for adults.

As mentioned above, although this invention was demonstrated based on the embodiment, this invention is not limited to the said embodiment, It can change suitably.

For example, in the diaper 1, as shown in FIG. 2, the exterior body 10 forms a continuous shape throughout the abdominal part A, the crotch part B, and the back part C, but instead of this shape, the exterior body 10 may be divided into In the form of the abdominal sheet member and the back sheet member, the absorptive main body 2 is stretched and fixed to the two sheet members.

In addition, all the parts of the above-mentioned only one embodiment can be used mutually appropriately. Regarding the embodiment of the present invention described above, the following supplementary notes are further disclosed.

<1>

A shorts-type absorbent article having a longitudinal direction extending from the wearer's abdominal side through a crotch portion to the back side and a transverse direction perpendicular to the longitudinal direction, and is divided into a crotch portion disposed on the wearer's crotch portion, a disposition The crotch part is arranged on the abdomen side of the wearer's abdomen side, and the back side part is arranged on the wearer's back side compared with the crotch part, and has an absorbent main body containing an absorber, and is arranged on the absorbent body. the exterior body on the non-skin-opposite side of the main body,

Both side edges of the outer body along the longitudinal direction of the abdomen portion and the back portion are joined to each other to form a waist opening and a pair of leg openings. In the pants-type absorbent article,

The exterior body includes an outer layer sheet disposed relatively far from the absorbent body, and an inner layer sheet disposed relatively close to the absorbent body,

At least a part of the exterior body is a composite stretchable portion having stretchability in the lateral direction, and in the composite stretchable portion, the outer layer sheet and the inner layer sheet are bonded by a plurality of joining portions arranged at intervals in the lateral direction. join,

In the above-mentioned composite stretchable portion in a natural state, the above-mentioned inner layer sheet has a wrinkle structure, and the wrinkle structure is composed of a plurality of concave strips extending in the longitudinal direction having the above-mentioned joining portion at the bottom, and a plurality of concave strips located between the concave strips. The curved portion of the inner layer sheet is configured as a convex portion at the top, and the outer layer sheet has a plurality of curved portions in a region overlapping with one of the convex portions of the inner layer sheet in plan view,

At least one of the abdominal portion and the back portion is provided with an outer body folded portion including a portion folded back so that the inner layer sheet is inside.

<2>

The underpants-type absorbent article according to <1> above, wherein

In the composite stretchable part in a natural state, there are two or more and ten or less of the above-mentioned curved parts between the above-mentioned adjacent joint parts, preferably two or more and five or less of them.

<3>

The underpants-type absorbent article according to <2> above, wherein

The interval between the above-mentioned adjacent joining portions is 2 mm to 15 mm, preferably 3 mm to 10 mm.

<4>

The underpants-type absorbent article according to any one of claims <1> to <3>, wherein:

The said exterior body folding part is arrange|positioned in the waist area|region including the longitudinal end of the said pants-type absorbent article.

<5>

The underpants-type absorbent article according to any one of claims <1> to <4>, wherein:

When the composite stretchable portion is compressed in the thickness direction, the outer layer sheet has a higher rate of reduction in thickness than the inner layer sheet.

<6>

The underpants-type absorbent article according to any one of claims <1> to <5>, wherein:

The outer layer sheet has stretchability in the lateral direction, and the inner layer sheet has no stretchability.

<7>

The underpants-type absorbent article according to any one of claims <1> to <6>, wherein:

The joining portion is constituted by a welded portion of the outer layer sheet and the inner layer sheet.

<8>

The underpants-type absorbent article according to any one of claims <1> to <7>, wherein:

The inner layer sheet has higher rigidity than the outer layer sheet.

<9>

The underpants-type absorbent article according to the above <8>, wherein

The ratio of the rigidity of the inner layer sheet to the rigidity of the outer layer sheet is 1.1 to 3.0, preferably 1.2 to 2.0.

<10>

The underpants-type absorbent article according to any one of <1> to <9> above, wherein:

In the above-mentioned composite stretchable portion, as the stretchable member that imparts stretchability to the composite stretchable portion, there is an elastic member disposed between the above-mentioned outer-layer sheet and the above-mentioned inner-layer sheet so as to be stretchable in the lateral direction.

<11>

The underpants-type absorbent article according to any one of <1> to <10> above, wherein:

In at least one of the abdominal portion and the back portion, the longitudinal end of the absorbent body is positioned on the inner side in the longitudinal direction than the longitudinal end of the pants-shaped absorbent article, and the region sandwiched by both longitudinal ends becomes the absorbent body. body non-configuration area,

The part of the above-mentioned composite elastic part located in the above-mentioned absorber non-arrangement area is compared with the part of the composite elastic part located in the absorber non-arrangement area adjacent to the absorber non-arrangement area in the above-mentioned longitudinal direction. The expansion ratio of the expansion and contraction member to which the expansion and contraction part imparts elasticity is low.

<12>

The underpants-type absorbent article according to <11> above, wherein

The part of the composite elastic part located in the region where the absorber is not arranged has a lower elongation stress than the part of the composite elastic part located in the region where the absorber is arranged.

<13>

The underpants-type absorbent article according to <11> or <12> above, wherein

The absorber non-arrangement region includes a waist region corresponding to the wearer's waist, and the absorber arrangement region includes an ilium region corresponding to a portion from the wearer's iliac crest to the anterior superior iliac spine.

<14>

The underpants-type absorbent article according to any one of <1> to <13> above, wherein

In the folded-back portion of the exterior body, the pattern of the ridges of the composite telescopic portion positioned outward in the thickness direction and the pattern of the ridges of the folded composite telescopic portion positioned inward in the thickness direction different.

<15>

The underpants-type absorbent article according to any one of <1> to <14> above, wherein:

In the folded-back portion of the exterior body, the grooved portion of the composite telescopic portion positioned outward in the thickness direction faces the grooved portion of the folded composite telescopic portion positioned inward in the thickness direction.

<16>

The underpants-type absorbent article according to any one of <1> to <15> above, wherein

In the folded-back portion of the exterior body, the ridge portion of the composite elastic portion located outward in the thickness direction faces the ridge portion of the folded composite elastic portion located inward in the thickness direction.

<17>

The underpants-type absorbent article according to the above <16>, wherein

In the said exterior body folding part, the said convex line part of the one said composite expansion-contraction part which opposes, and the said convex line part of the other said composite expansion-contraction part are bonded.

<18>

The underpants-type absorbent article according to the above <17>, wherein

The bonded portion between the opposing ridge portions extends in the longitudinal direction.

<19>

The underpants-type absorbent article according to any one of <1> to <18> above, wherein

The above-mentioned engaging portion extends in the above-mentioned longitudinal direction.

<20>

The underpants-type absorbent article according to any one of <1> to <19> above, wherein

The basis weight of the outer layer sheet is 20 g/m ² to 60 g/m ² , preferably 30 g/m ² to 55 g/m ² .

<21>

The underpants-type absorbent article according to any one of <1> to <20> above, wherein

The basis weight of the inner layer sheet is 13 g/m ² to 30 g/m ² , preferably 15 g/m ² to 25 g/m ² .

Industrial availability

According to the present invention, it is possible to provide an underpants-type absorbent article that has an exterior body that is excellent in cushioning and air permeability, and that is less prone to pressure marks on the skin and less likely to be stuffy even for a wearer who is often in a sleeping position.

Claims (21)

1. A shorts-type absorbent article having a longitudinal direction extending from the wearer's abdominal side through the crotch portion to the back side and a transverse direction perpendicular to the longitudinal direction, and being divided into a crotch portion disposed on the wearer's crotch portion , the abdominal part arranged closer to the wearer's abdominal side than the crotch part, and the back side part arranged closer to the wearer's back side than the crotch part, and has an absorbent main body containing an absorber, and is arranged on the the outer body on the non-skin-facing side of the absorbent main body, Both side edges of the outer body along the longitudinal direction of the abdominal part and the back part are joined to each other to form a waist opening and a pair of leg openings. The pants-type absorbent Sexual objects are characterized by: The exterior body includes an outer layer sheet arranged relatively far from the absorber, and an inner layer sheet arranged relatively close to the absorber, At least a part of the exterior body is a composite stretchable portion stretchable in the lateral direction, and in the composite stretchable portion, the outer layer sheet and the inner layer sheet are arranged at intervals in the lateral direction. multiple junctions are joined, In the composite stretchable portion in a natural state, the inner layer sheet has a wrinkled structure consisting of a plurality of concave strips extending in the longitudinal direction having the joining portion at the bottom, and The outer layer sheet has a plurality of curved parts in a region overlapping with one of the convex parts of the inner layer sheet in plan view. , At least one of the abdominal portion and the dorsal portion is provided with an outer body folded portion that is folded back so that the inner layer sheet is inward including the composite stretchable portion. part. 2. The pants-type absorbent article according to claim 1, characterized in that: In the compound expansion-contraction part in a natural state, there exist two or more and ten or less said bending parts between the said adjacent junction parts. 3. The pants-type absorbent article according to claim 2, characterized in that: The interval between the adjacent junctions is not less than 2 mm and not more than 15 mm. 4. The underpants-type absorbent article according to any one of claims 1 to 3, characterized in that: The exterior body folded portion is disposed in a waist region including longitudinal ends of the pants-type absorbent article. 5. The pants-type absorbent article according to any one of claims 1 to 4, characterized in that: When the composite stretchable portion is compressed in the thickness direction, the outer layer sheet has a higher rate of reduction in thickness than the inner layer sheet. 6. The pants-type absorbent article according to any one of claims 1 to 5, characterized in that: The outer layer sheet is stretchable in the transverse direction, and the inner layer sheet is not stretchable. 7. The underpants-type absorbent article according to any one of claims 1 to 6, characterized in that: The joining portion is constituted by a welded portion of the outer layer sheet and the inner layer sheet. 8. The underpants-type absorbent article according to any one of claims 1 to 7, characterized in that: The inner layer sheet is more rigid than the outer layer sheet. 9. The pants-type absorbent article according to claim 8, characterized in that: The ratio of the rigidity of the inner layer sheet to the rigidity of the outer layer sheet is 1.1 or more and 3.0 or less. 10. The underpants-type absorbent article according to any one of claims 1 to 9, characterized in that: The composite stretchable portion includes an elastic member disposed between the outer layer sheet and the inner layer sheet so as to be stretchable in the lateral direction as the stretchable member that imparts stretchability to the composite stretchable portion. 11. The pants-type absorbent article according to any one of claims 1 to 10, characterized in that: In at least one of the abdominal portion and the back portion, the longitudinal end of the absorbent body is positioned on the inner side in the longitudinal direction than the longitudinal end of the pants-type absorbent article, and is sandwiched by both longitudinal ends. The area where the absorber is placed becomes the non-disposition area of the absorber, The part of the composite elastic part located in the absorber non-arrangement area is compared with the part of the composite elastic part located in the absorber non-arrangement area adjacent to the absorber non-arrangement area in the longitudinal direction, The stretching ratio of the stretchable member that imparts stretchability to the composite stretchable portion is low. 12. The pants-type absorbent article according to claim 11, wherein: The part of the composite elastic part located in the region where the absorber is not arranged has a lower elongation stress than the part of the composite elastic part located in the region where the absorber is arranged. 13. The pants-type absorbent article according to claim 11 or 12, characterized in that: The absorber non-arrangement region includes a waist region corresponding to the wearer's waist circumference, and the absorber arrangement region includes an ilium region corresponding to a position from the wearer's iliac crest to the anterior superior iliac spine. 14. The pants-type absorbent article according to any one of claims 1 to 13, characterized in that: In the folded-back portion of the exterior body, the pattern of the protruding lines of the composite elastic portion located on the outer side in the thickness direction and the pattern of the folded composite elastic portion located on the inner side in the thickness direction The patterns of the ribs are different. 15. The pants-type absorbent article according to any one of claims 1 to 14, characterized in that: In the folded-back portion of the exterior body, the concave portion of the composite elastic portion located on the outer side in the thickness direction and the concave portion of the folded composite elastic portion located on the inner side in the thickness direction The bars are opposite to each other. 16. The pants-type absorbent article according to any one of claims 1 to 15, characterized in that: In the folded-back portion of the exterior body, the ridges of the composite telescopic portion located on the outer side in the thickness direction and the protrusions of the folded composite telescopic portion located on the inner side in the thickness direction The bars are opposite to each other. 17. The pant-type absorbent article of claim 16, wherein: In the folded-back portion of the exterior body, the protruding line portion of the one of the opposing composite expandable portions is bonded to the protruding line portion of the other composite expandable portion. 18. The pant-type absorbent article of claim 17, wherein: Adhesive portions of the opposing rib portions extend in the longitudinal direction. 19. The pants-type absorbent article according to any one of claims 1 to 18, characterized in that: The engagement portion extends in the longitudinal direction. 20. The pants-type absorbent article according to any one of claims 1 to 19, characterized in that: The basis weight of the outer layer sheet is not less than 20 g/m ² and not more than 60 g/m ² . 21. The pants-type absorbent article according to any one of claims 1 to 20, characterized in that: The grammage of the inner layer sheet is not less than 13 g/m ² and not more than 30 g/m ² .

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