WO2013080837A1

WO2013080837A1 - Absorption structure and absorbent wearable object employing same

Info

Publication number: WO2013080837A1
Application number: PCT/JP2012/080027
Authority: WO
Inventors: 竜吾大橋; 湊　大尚
Original assignee: ユニ・チャーム株式会社
Priority date: 2011-11-30
Filing date: 2012-11-20
Publication date: 2013-06-06
Also published as: TWI568428B; CN103957858A; JP5769604B2; CN103957858B; JP2013111419A; TW201334764A

Abstract

Provided are an absorption structure and an absorbent wearable object employing same, with which the rate of absorption is superior due to having a shape of uneven thickness, and with which there is no concern about bending, etc., occurring which might give rise to a leakage of bodily fluids while being worn by disposing locally highly rigid regions therein. An absorption structure (17) comprises a first end edge (17a) and a second end edge (17b), a thick part (55) located in the first end edge (17a) side, a thin part (57) located in the second end edge (17b) side which has a smaller thickness measurement than the thick part (55), and a thickness gradient part (56) which is located between the thick part (55) and the thin part (57) in which the thickness measurement gets steadily smaller from the first end edge (17a) toward the second end edge (17b). A debossing working is carried out which forms a plurality of compressed depression parts (60) to the thin part (55), the thickness gradient part (56), and on portions of the thickness gradient part (56) which are adjacent to the thick part (55).

Description

Absorbent structure and absorbent wearing article using the same

The present invention relates to an absorbent structure having body fluid absorbability and an absorbent wearing article using the same, and more specifically, an absorbent structure having a non-uniform thickness dimension, a disposable diaper using the same, and a sanitary The present invention relates to absorbent wearing articles such as napkins and incontinence pads.

Conventionally, an absorbent structure having a non-uniform thickness and an absorbent article using the same are known. For example, Patent Document 1 discloses an absorbent structure having a thick part having a required thickness and a thin part having a thickness dimension smaller than the thick part, and an absorbent article using the same. .

JP 2004-65929 A

Since the absorbent article disclosed in Patent Document 1 includes an absorbent structure having a locally high absorption capacity in the thick part, the thick part is formed in a region where a relatively large amount of body fluid is excreted. By arranging, the absorption performance can be sufficiently exhibited. Moreover, in this absorption structure, since the thin part is formed in the area | region where a bodily fluid is excreted comparatively a little, it can be said that it is excellent in absorption efficiency.

However, since a step is formed at the boundary between the thick part and the thin part, there is a possibility that the wearer may feel uncomfortable, and the step is caused by the absorption structure being curved along the wearer's body during wearing. There is a possibility that local cracking or the like occurs in the part, and leakage of body fluid may occur. Further, even when such a step is relatively small, if the rigidity of the portion located in the crotch region and pressed between the thighs of the wearer is relatively low, the portion is deformed and the absorbent structure There is a risk that the whole body will crack and leak fluid.

The problem of the present invention is that the absorption efficiency is excellent by having a non-uniform thickness, and bending that may induce leakage of body fluid during wearing is caused by providing a high rigidity region locally An object of the present invention is to provide an absorbent structure having no fear and an absorbent wearing article using the same.

In order to solve the above problems, the first invention of the present application has at least a longitudinal direction and a transverse direction perpendicular thereto, and is interposed between a liquid-permeable top sheet and a liquid-impermeable back sheet, The present invention relates to an absorbent structure for an absorbent wearing article including a liquid-absorbent core having body fluid absorbency.

The absorbent structure according to the first invention of the present application includes a first end edge, a second end edge facing the first end edge in the longitudinal direction, a thick portion located on the first end edge side, and a position on the second end edge side. A thin portion having a thickness dimension smaller than that of the thick portion, and located between the thick portion and the thin portion, and gradually having a thickness dimension from the first edge side toward the second edge side. A thickness gradient portion that becomes smaller, and the thin portion, the thickness gradient portion, and a portion of the thick portion adjacent to the thickness gradient portion are subjected to debossing to form a number of compression recesses. It is characterized by.

The second invention of the present application is the first and second end edges, the thick part located on the first end side, and the thin part having a smaller thickness than the thick part located on the second end side. And a thickness gradient portion that is located between the thick portion and the thin portion and gradually decreases in thickness from the first end side toward the second end side, and the thin portion An absorbent structure that has been subjected to debossing to form a number of compression recesses in the thickness gradient portion and a portion of the thick portion adjacent to the thickness gradient portion, a front waist region, and a rear A diaper body having a waist region and a crotch region located between the front and rear waist regions, wherein the absorbent structure extends from the front waist region to the rear waist region, and the first edge of the absorbent structure Is located on the front waist region side, and the second end edge is located on the rear waist region side. It said adjacent portion and said thickness gradient portion relates to an absorbent wearing article positioned in the crotch region.

According to the absorption structure according to one or more inventions of the present application, since the thickness gradient portion is located between the thick portion and the thin portion, a step due to a sudden change in thickness dimension is generated. Absent. In addition, since a large difference in rigidity is not produced between the thin portion and the thick portion by debossing the thin portion and the thickness gradient portion, body fluid may be caused by partial cracks due to changes in rigidity or the occurrence of steps. There is no risk of leakage. Further, since a high-stiffness area that has been subjected to debossing to form a large number of compression recesses is located in a part adjacent to the thickness gradient part of the thick part, the part is clamped and deformed. There is no risk of partial cracking or tearing even if the force is applied.

In an absorbent wearing article provided with such an absorbent structure, the thick part of the absorbent structure can sufficiently exhibit its absorption performance by being located in the front waist region and the crotch region where urine is excreted, Since the thin part is located in the rear waist region, the wearability of the wearer's buttocks is improved, and the absorption efficiency of the entire absorbent structure is excellent. In addition, since the high rigidity region formed in the portion adjacent to the thickness gradient portion of the thick portion is located in the crotch region, even if the portion is sandwiched between the wearer's thighs, partial cracking or tearing occurs. There is no risk of it occurring.

The perspective view of a disposable diaper shown as an example of the absorbent wearing article using the absorption structure concerning a 1st embodiment of the present invention. The expansion | deployment top view of the diaper of 1st Embodiment of this invention. FIG. 3 is a sectional view taken along line III-III in FIG. 2. The top view of the absorption structure which shows the external shape of a diaper with a virtual line. FIG. 5 is a sectional view taken along line VV in FIG. 4. The figure which shows a part of manufacturing process of an absorption structure. The side view of a deboss roller. The top view similar to FIG. 4 in the diaper of 2nd Embodiment of this invention. The top view similar to FIG. 4 in the diaper of 3rd Embodiment of this invention. XX sectional drawing of FIG.

1 and 2, a diaper 10 has a longitudinal axis P and a transverse axis Q orthogonal thereto, a longitudinal direction Y parallel to the longitudinal axis P, and a transverse direction X parallel to the transverse axis Q, and a front waistline. The diaper main body 14 provided with the area | region 11, the back waist area 12, and the crotch area 13 located between the front-and-

back waist areas

11 and 12 is included.

The diaper main body 14 includes a front end edge 14a and a rear end edge 14b that extend straight in the lateral direction X,

side edges

14c and 14d that are inwardly bent in the crotch region 13, and a top sheet 15 that is positioned on the skin facing surface side. And a liquid-impermeable back sheet 16 positioned on the non-skin facing surface side, and an absorbent structure 17 interposed between the top sheet 15 and the back sheet 16. Further, an intermediate sheet 18 is optionally disposed between the top sheet 15 and the absorbent structure 17, and a pair of containment sheets 20 symmetrical about the vertical axis P is disposed on the skin facing surface side of the diaper 10. Has been.

The top sheet 15 can be formed from various fiber nonwoven fabrics having substantially liquid permeability, for example, air-through fiber nonwoven fabrics having a mass of about 15 to 45 g / m ² , porous plastic films, laminate sheets thereof and the like.

The backsheet 16 is made of various known fiber nonwoven fabrics that are substantially liquid-impervious, such as spunbond nonwoven fabrics, point bond nonwoven fabrics, SMS (spunbond meltblown materials having a mass in the range of about 10 to 40 g / m ^2. -Spun band) It can be formed from a nonwoven fabric, a liquid-impervious plastic film, or a laminate sheet with at least one of these nonwoven fabrics.

The intermediate sheet 18 can be formed of various known fiber nonwoven fabrics that are substantially air permeable and liquid permeable, such as an air-through nonwoven fabric having a mass of about 15 to 45 g / m ² , and is a cushion against the wearer's skin. In addition to improving the performance, the body fluid is not diffused into the delusion and the top sheet 15 and the absorption structure 17 are separated to prevent the body fluid from flowing back to the top sheet 15 in the delusion.

The containment sheet 20 can be formed from a hydrophobic fiber nonwoven fabric, a moisture-permeable and leak-proof plastic film, a laminate thereof, and the like. For example, as the nonwoven fabric, an SMS fiber nonwoven fabric or a span having a mass of about 10 to 30 g / m ² can be used. It can be formed from a bond fiber nonwoven fabric or the like.

2 and 4, the absorbent structure 17 includes front and rear end edges (first and second end edges) 17a and 17b, and both

side edges

17c and 17d extending in the longitudinal direction Y between the front and

rear end edges

17a and 17b. Have For convenience of explanation, both

side edges

17c and 17d are concave curved to bend to the vertical axis P in the vicinity of the central portion of the straight portion 21 and the crotch region 13 that extend straight on the front waist region 11 side and the rear waist region 12 side. Section 22. Further, the

side edges

17c and 17d have

bent portions

23 and 24 located at portions where the straight portion 21 and the concave curved portion 22 intersect. As will be described later, a front area (first area) 51 is formed between the straight sections 21 on the front waist area 11 side, a rear area (second section) 52 is formed between the straight sections 21 of the rear waist area 12, and a concave curved section. A central portion 53 is defined between 22.

The absorbent structure 17 is composed of a superabsorbent polymer particle (SAP), fluff pulp, and optionally a thermoplastic synthetic fiber (staple fiber) and shaped into a predetermined shape, and its shape retention. And a sheet having liquid diffusibility, for example, formed from a non-woven fiber nonwoven sheet having liquid permeability, which covers the liquid-absorbing core for improving liquid diffusibility. On the lower surface of the absorbent structure 17, a leak-proof sheet 25 formed from a liquid-impervious fiber nonwoven fabric is disposed. The absorbent structure 17 may be formed of only the liquid-absorbent core as long as the effects of the present embodiment described later are exhibited.

The leak-proof sheet 25 is a moisture-permeable and leak-proof plastic film, a substantially liquid-impervious SMS (spunbond / meltblown / spunbond) fiber nonwoven fabric, a spunbond fiber nonwoven fabric having a mass of about 10 to 30 g / m ² , Or it can form from a laminate sheet etc. with at least one of those nonwoven fabrics.

Referring to FIG. 2, the diaper main body 14 includes front and

rear end flaps

27 and 28 extending in the lateral direction X outside the front and

rear end edges

17 a and 17 b of the absorbent structure 17, and both sides of the absorbent structure 17. A pair of

side flaps

29 and 30 extending in the vertical direction Y are provided outside the

edges

17c and 17d in the horizontal direction X. The front and rear end flaps 27 and 28 include a containment sheet 20, a top sheet 15, a leak-proof sheet 25, and a back sheet 16 that extend outward in the vertical direction Y from the front and rear end edges 17 a and 17 b of the absorbent structure 17. It is formed by overlapping each other. Moreover, the side flaps 29 and 30 are the top sheet | seat 15, the containment sheet | seat 20, the leak-proof sheet | seat 25, and the back sheet | seat 16 extended to the outward of the horizontal direction X of the both-

sides edges

17c and 17d of the absorption structure 17. Are formed by overlapping each other.

A fixing portion 34a of a pair of tape fastener tabs 34 is interposed between both side edges of the containment sheet 20 and the back sheet 16 of the rear side flap 32 where the rear end flap 28 and the side flaps 29 and 30 intersect. It is fixed via a hot melt adhesive applied to the inner surfaces of both

sheets

16 and 20. A first fastening element 35 having a hook group of mechanical fasteners is provided on a free portion 34b of the tape fastener tab 34 extending outward in the lateral direction X from the side edge of the rear side flap 32 (side edge of the rear waist region 12). Is provided. In the wearing state of the diaper 10, the first fastening element 35 is removably fastened to the second fastening element 36 having a loop group of mechanical fasteners extending in the lateral direction X on the outer surface of the front waist region 11. An opening 37 and a pair of leg openings 38 are defined (FIG. 1).

An elastic waistband formed of a belt-like elastic repulsion member having cushioning properties such as urethane foam having open cells between the top sheet 15 and the leak-proof sheet 25 forming part of the front and rear end flaps 27 and 28 40 is disposed. Further, between the back sheet 16 forming a part of the side flaps 29 and 30 and the containment sheet 20, a plurality of strand-like or string-like leg elastic elements 41 can shrink in the longitudinal direction Y. (Not shown).

The containment sheet 20 includes a proximal edge 42 that forms part of the side flaps 29 and 30, a skin facing surface of the top sheet 15 in the front and

rear waist regions

11 and 12, and a lateral direction X from the top sheet 15 of the back sheet 16. The front and rear

fixed end portions

43 and 44 fixed to the skin-facing surface of the portion extending outwardly with a hot-melt adhesive, and the burr sheet 20 extending in the longitudinal direction Y between the front and rear

fixed end portions

43 and 44. And a distal edge 45 formed by bending the inner edge of the inward. A plurality of strand-like or string-like cuff elastic elements 46 extending in the longitudinal direction Y are fixed to the distal edge 45 so as to be contractible in the longitudinal direction Y. The distal edge 45 is separated from the skin-facing surface of the top sheet 15 by the contraction action of the cuff elastic element 46 when the diaper 10 is worn, and a pair of containment cuffs for preventing side leakage of excrement is formed. .

3 to 5, the thickness direction of the absorbent structure 17 is indicated by Z in FIG. 4, and the absorbent structure 17 includes a front region (first region) 51 located on the front waist region 11 side and a front region 51. The center located between the inwardly bent portions 22 of the side edges 17c and 17d between the rear region (second region) 52 located on the rear waist region 12 side and the front region 51 and the rear region 52 Part 53. The absorption structure 17 has a thicker portion 55 in which the front region 51 is thicker than the rear region 52, specifically, a relatively thick wall portion 55 extending from the front region 51 to a part of the rear region 52; Thickness dimension from the thick part 55 extending from the thick part 55 to the rear end edge 17b, and the thickness gradient part 56 extending gradually from the thick part 55 to the bottom side of the absorption structure 17 in the rearward direction. And a small thin portion 57. In the present embodiment, the absorbent structure 17 is formed of a single layer extending in the longitudinal direction Y. However, the region is divided into two layers so that the thick portion 55 is thicker than the thin portion 57. Alternatively, the entire absorbent structure 17 including the thin portion 57 may be formed of a plurality of layers.

However, when the entire absorbent structure 17 is formed of a single layer as in the present embodiment, the pulp fibers and options contained in the entire absorbent structure 17 are compared with the case where it is formed of a plurality of layers. Since it is mixed with thermoplastic fibers added as, it is hard to collapse and has excellent shape retention.

When the absorbent structure 17 is formed as a single layer, the shape can be formed using a known manufacturing method and manufacturing apparatus, and for example, it can be formed by the following method.

<Method of forming thick portion 55, thickness gradient portion 56 and thin portion 57>
In a manufacturing apparatus having an absorbent material supply means formed from fluffed wood pulp and / or superabsorbent polymer particles and a rotary suction drum having a plurality of concave molds, the absorbent material is recessed from the supply means via a transfer pipe. Accumulated in a mold to form an aggregate (liquid absorbent core). The concave mold of the drum has a mesh shape with a plurality of apertures at the bottom, and the absorbent material is sucked and accumulated in the concave mold through the apertures. Depth dimensions (separation dimensions from the surface of the plate to the bottom of the concave mold) are different so that portions corresponding to the thick portion 55, the thickness gradient portion 56, and the thin portion 57 are formed. Specifically, the thick portion 55 of the absorbent structure 17 having a required thickness is formed in a portion having a relatively large depth dimension, and the thin portion 57 is formed in a portion having a relatively small depth dimension. Furthermore, a thickness gradient portion 56 is formed at the inclined portion located between the two.

The absorbent structure 17 has a unique shape with a non-uniform thickness as a whole, and in the front waist region 11 and the crotch region 13, a required amount of body fluid is obtained by the thick portion 55 having a required absorption capacity. Primarily excreted urine can be reliably absorbed. Moreover, since the thin part 57 is located in the back waist region 12 side with less excretion amount of the body fluid compared with the front waist region 11 and the crotch region 13, it does not use for absorption of the body fluid in the whole absorption structure 17. There are almost no parts, and it can be said that the absorption efficiency is excellent as compared with a conventional absorption structure having a fixed shape and configuration. Furthermore, the production cost can be suppressed by minimizing the amount of the liquid-absorbent core used for the absorbent structure 17.

By forming the thickness gradient portion 56 and the thin portion 57, the rear region 52 becomes relatively thin toward the rear, so that the rear waist region 12 is deformed along the shape of the wearer's body. It becomes easy to fit and can improve a feeling of wearing. Furthermore, by reducing the thickness of the entire diaper 10, the diaper 10 is folded in two so that the front and

rear waist regions

11, 12 are overlapped with each other, and is not bulky. Capacity is improved.

In the absorbent structure 17, when the thick portion 55 and the thin portion 57 are directly adjacent to each other, a difference in rigidity due to a sudden change in thickness and a step between the thick portion 55 and the thin portion 57. There is a possibility that not only the wearer may feel uncomfortable by the formation of, but also a part of the absorbent structure 17 may be bent or swung near the boundary to induce leakage of body fluid. However, in the present embodiment, since the thickness gradient portion 56 is formed between the thick portion 55 and the thin portion 57, the thickness dimension changes gradually, and the rigidity due to the sudden change in the thickness dimension. Since no difference or level difference is formed, there is no risk of giving the wearer a sense of incongruity, and there is no risk of bending or twisting inducing a fluid leak in the vicinity of the boundary between the

portions

55, 56, and 57. .

Referring to FIG. 5, it is preferable that the thin portion 57 is formed in a region where the absorption performance of the absorbent structure 17 is not hindered, that is, a region where body fluid is not excreted so much. Specifically, it is preferable that the thin portion 57 is located on the rear waist region 12 side and has a size of about 40% with respect to the entire area of the absorbent structure 17. In addition, the thickness gradient portion 56 has a length dimension L1 in the longitudinal direction Y of the absorbent structure 17 in order to prevent the wearer from feeling uncomfortable by causing a stiffness difference and a step due to a sudden change in the thickness gradient. Is about 320 to 450 mm, the length dimension L2 in the longitudinal direction Y is preferably about 25 to 70 mm, and more preferably about 35 to 60 mm. When the length dimension L2 in the vertical direction Y of the thickness gradient portion 56 is about 25 mm or less, the length of the gradual height gradient with respect to the difference in thickness dimension between the thick portion 55 and the thin portion 57 is insufficient. Thus, a step is formed in the vicinity of the boundary between the thin portion 57 and the thickness gradient portion 56, which may give the wearer a feeling of strangeness. Further, when the length dimension L2 in the longitudinal direction Y of the pressure gradient portion 56 is 70 mm or more, the formation region of the thick portion 55 with respect to the entire absorption structure 17 becomes small, and the body fluid by providing the thick portion 55 There is a possibility that the effect of securing the absorption capacity in this embodiment may be impaired.

Regarding the formation of each

region

55, 56, 57 of the absorbent structure 17, the thick portion 55 has a thickness dimension of about 2.7 to 3.3 mm, and the liquid absorbent core has a mass of about 220 to 260 g. / M ² pulp fiber and SAP with a mass of about 180-220 g / m ² , and the thin portion 56 has a thickness of about 2.2-2.8 mm, and the absorbent core has a mass of about It can be formed from a mixture of 180 to 220 g / m ² pulp fiber and SAP having a mass of about 140 to 180 g / m ² . That is, the mass per unit area of the thin portion 57 is lower than that of the thick portion 55. Specifically, in order to achieve the effect of the present invention, the mass per unit area of the absorbent core of the thin portion 57 is The thickness per unit area of the thick portion 55 is preferably in the range of about 50 to 85%.

The thickness dimension of each area | region of the absorption structure 17 can be measured using a thickness measuring device (the product made by PEACOCK, measurement pressure: 12.5 g / cm < ² >). Specifically, the thickness of the thick part 55 and the thin part 57 is determined by taking the absorbent structure 17 out of the diaper 10, and in the portions corresponding to the thick part 55 and the thin part 57, respectively. The sample is cut to a size of about 50 mm in length of Y × about 50 mm in length in the lateral direction X, and the thickness of the central part of the sample is measured with a thickness meter.

Referring to FIG. 4, in the rear region 52 of the absorbent structure 17, a first debossed portion in which a plurality of compression recesses 60 are arranged in a staggered manner when viewed in the longitudinal direction Y of the absorbent structure 17 in the thin portion 57. 61, a second debossed portion in which a plurality of compression recesses 60 are arranged in a staggered manner in the longitudinal direction Y of the absorbent structure 17 in the thickness gradient portion 56 and the thickness portion 55 adjacent to the thickness gradient portion 56 63 is provided. By providing the first and second debossed

portions

61 and 63, the thin portion 57, the thickness gradient portion 56, and the adjacent portion have higher rigidity than when the debossed portion is not applied. ing. In the adjacent portion where the second debossed portion 63 of the thick portion 55 is formed, a high rigidity region 64 having higher rigidity than the other portions of the thick portion 55 and having the highest rigidity in the absorbent structure 17 is provided. It is formed.

As described above, in the present embodiment, by adjusting the thickness of the absorption structure 17, areas having different absorption capacities are formed, and there is a possibility that a difference in rigidity may occur at a portion where the thickness changes. In order to reduce such a difference in rigidity, a thickness gradient portion 56 is formed between the thick portion 55 and the thin portion 57, but by forming the first and second debossed

portions

61 and 63, The rigidity of the thin portion 57 and the thickness gradient portion 56 can be increased, and the difference in rigidity between the thin portion 57 and the thick portion 55 can be further reduced, and further deformation and loss of shape due to partial cracking of the absorbent structure 17 can be further achieved. Can be prevented.

4 and 5, the high-rigidity region 64 is located between the bent portions 24 of the side edges 17c and 17d and the vicinity thereof. The bent portion 24 and the vicinity thereof are portions where the straight portion 21 and the curved portion 22 intersect each other, and the absorption structure 17 is most cracked or wrinkled due to a change in shape and movement of the wearer's crotch. And even if the thick portion 55 has higher rigidity than the thickness gradient portion 56 and the thin portion 57, the warp of the region is the thickness gradient portion 56. The entire rear region 52 may reach the thin portion 57 and be separated from the wearer's body, inducing leakage of body fluid. In addition, the curved portion 22 of the absorbent structure 17 has a curved shape so as to fit along the wearer's thigh in a worn state, but when the wearer is a relatively old infant, The bent part 24 and the part behind it are clamped between the thighs, and a force to deform it acts. In this embodiment, the high rigidity region 64 having the highest rigidity in the absorbent structure 17 is provided in such a region, so that the bending region 24 is prevented from being bent and the entire rear region 52 is worn by the wearer. Can be prevented from being separated from the body.

As a method of forming the high-rigidity region 64, for example, the mass per unit area of the liquid-absorbent core can be locally increased to design the region to be the thickest. The region acts like a rib, and the entire absorbent structure 17 becomes difficult to bend along the shape of the wearer's body, which may reduce the fit. In the case of this embodiment, since the high-stiffness region 64 is defined by the second debossed portion 63 that has been subjected to debossing, cracks and deformation starting from the vicinity of the region can be suppressed, while the absorption structure The body 17 can be curved along the shape of the wearer's body, and body fluid leakage prevention due to deformation or the like and securing of the fit to the wearer's body can be realized.

The plurality of compression recesses 60 forming the first and second debossed

portions

61 and 63 have a substantially circular shape having substantially the same size, and the second debossed portion 61 is relatively densely connected to the second debossed

portion

61 and 63. The debossed parts 63 are arranged relatively sparsely. Therefore, the total area ratio of the compressed recesses 60 including the first debossed portion 61 as a whole is higher than the total area ratio of the compressed recesses 62 including the second debossed portion 63 as a whole. Specifically, the total area ratio of the former compression recess 60 is about 12 to 18%, whereas the total area ratio of the latter compression recess 60 is about 5.0 to 9.0%. Further, the length dimension (depth) in the thickness direction Z of the compressed recess 60 is about 0.2 to 0.5 mm.

By making the total area ratio of the compression recesses 60 of the first debossed portion 61 larger than that of the second debossed portion 63, the difference in rigidity between the thin portion 57 and the thickness inclined portion 56 is reduced, and those Deformation of the absorbent structure 17 starting from the vicinity of the boundary can be prevented. Moreover, in the thickness inclination part 56, the 1st debossed part 61 is provided in the site | part by the side of the thin part 57, and the 2nd debossed part 63 is provided in the site | part by the side of the thick part 55 thicker than this part. Therefore, the rigidity does not change abruptly even in the thickness gradient portion 57, and deformation and bending of the absorbent structure 17 starting from the thickness inclined portion 56 can be prevented.

Referring to FIG. 4, the first and second debossed

portions

61 and 63 are formed with non-compressed portions that are not provided with a series of compression recesses 60 extending in the lateral direction X. By forming the non-compressed portion, the absorbent structure 17 has a required flexibility, and by forming the non-compressed portion at least in the second debossed portion 63, the thickness gradient portion 56 and the high rigidity region are formed. It becomes easy to curve 64 along a wearer's body. As long as the above-described effects are exhibited, the value of the total area ratio of the compression recesses 60 in the first and second debossed

portions

61 and 63 can be changed as appropriate, and various known patterns can be used as deboss patterns in addition to the staggered pattern. You may employ | adopt and the shape of the compression recessed part 60 may have various well-known shapes, such as an ellipse, a rhombus, and a strip shape other than circular.

<Method for Manufacturing Absorbent Structure 17>
Referring to FIG. 6, a continuous absorbent structure 71 formed by connecting portions corresponding to the plurality of absorbent structures 17 in series via a transport roll (not shown) is transported in the machine direction MD. The continuous absorbent structure 71 is formed by encapsulating a liquid absorbent core composed of a single layer or a plurality of layers with a liquid core wrap sheet, and the thickness gradient portion 56 and the thin portion of each absorbent structure 17 A portion 71a corresponding to 57 is recessed downward and thin.

Referring to FIGS. 6 and 7, the debossing process for applying the first and second debossed

portions

61 and 63 to the absorbent structure 17 is a deboss that rotates in one direction and is located above the continuous absorbent structure 71. A roller 72 and an anvil roller 73 having a smooth outer peripheral surface that rotates in the opposite direction to the deboss roller 72 disposed opposite to the roller 72 are configured. A part of the outer peripheral surface of the deboss roller 72 has a first end edge 74a and a second end edge 74b, and gradually increases in thickness as it extends in the circumferential direction from the first end edge 74a to the second end edge 74b. A raised portion 74 is provided. The raised portion 74 further has a thin portion 75 located on the first end edge 74a side and a thick portion 76 located on the second end edge 74b side. A plurality of bosses 77 protrude from the surface of the raised portion 74 and a part of the outer peripheral surface of the deboss roller 72 on the first end edge 74a side. The boss 77 includes a first deboss group 78 corresponding to the first debossed portion 61 of each absorbent structure 17 formed in the thick portion 76 of the raised portion 74 and each absorbent structure 17 formed in the thin portion 75. The second debossing portion 63 is divided into a second debossing group 80 which is larger than the first debossing group 78 and is relatively sparsely arranged. In addition, in order to form the compression recessed part 60 stably in the continuous absorption structure 71, the boss | hub 77 may be heated to such an extent that the sheet | seat member which comprises it is not melt | fused.

The deboss roller 72 has a rotational speed and a continuous absorption structure such that a raised portion 74 formed on the outer peripheral surface thereof faces a portion 71 a corresponding to the thickness gradient portion 56 and the thin portion 57 of the continuous absorption structure 71. The conveyance speed of the body 71 is adjusted and synchronized, and the first debossed portion 61 is formed by pressing the portion corresponding to the thin portion 57 by the first deboss group 78 of the thick portion 76 of the raised portion 74. The second debossed portion 80 is formed by pressing the portion corresponding to the thickness gradient portion 56 and the high rigidity region 64 of the thick portion 55 by the second deboss group 80 of the thin portion 75 of the raised portion 74. .

According to this debossing process, the raised portions 74 can be formed on one deboss roller 72, and the first and second debossed

portions

61, 63 having different patterns can be formed simultaneously. 63, the manufacturing process can be said to be simpler than when different debossing rollers are used. Further, since the raised portion 74 has a different thickness depending on the shape of the pressed portion of the continuous absorbent structure 71, the thickness gradient portion 56 is pressed relatively strongly and its rigidity is more than necessary. In addition, since the thin portion 57 is pressed by the thick portion 76 of the raised portion 74, the thin portion 57 can be provided with a required rigidity and can be formed thin.

In the debossing process, in addition to the above configuration, the first and

second deboss groups

78 and 80 have the same total area ratio of the bosses 77 and have different lengths of the bosses 77, that is, correspond to the thin portions 57. The length dimension of the boss 77 of the first deboss group 78 to be larger than that of the boss 77 forming the second deboss group 80, and higher rigidity may be imparted. Also, using two debossing rollers having different debossing patterns, one debossing roller performs debossing in a range corresponding to the first and second

debossing processing parts

61 and 63, and the other debossing roller performs the first debossing process. Only a portion corresponding to the portion 61 may be further debossed.

<Bending rigidity of thick part 55 and thin part 57 of absorption structure 17>
Speaking of the bending rigidity of the thick portion 55 and the thin portion 57 of the absorbent structure 17, the bending rigidity in the region other than the high rigidity region 64 in the thick portion 55 is about 0.07 to 0.14 N, which is a high rigidity. The bending rigidity of the region 64 is about 0.09 to 0.2N, and the bending rigidity of the thin portion 57 is about 0.04 to 0.07N. The difference in rigidity value between the thick portion 55 and the thin portion 57 is preferably about 0.04 N or less. When the rigidity value is 0.04 N or more, even if the thickness inclined portion 56 for buffering a sudden change in rigidity is provided, the absorption structure 17 is deformed due to a large difference in the rigidity value. May cause some cracks. Further, when the rigidity value of the high rigidity region 64 is 0.2 N or more, the rigidity value of the region in the entire absorption structure 17 is higher than that of other regions, and the absorption structure 17 is cracked starting from that. May occur or deform.

<Measuring method of bending rigidity of thick portion 55 and thin portion 57 of absorbent structure 17>
The bending rigidity of each part of the thick part 55 and the thin part 57 of the absorbent structure 17 can be measured using a Taber-type bending resistance tester. Specifically, the absorbent structure 17 is taken out from the diaper 10, and the thick portion 55 and the thin portion 57 are approximately rectangular having a length dimension of about 70 mm in the vertical direction X and a length dimension of about 38.1 mm in the horizontal direction X. A sample cut into a shape is prepared, and the Taber bending stiffness value of each part is measured using the test machine so that the transverse direction X is the bending direction. However, since the high rigidity region 64 of the thick portion 55 is not the size having the measurement dimension, the bending rigidity is measured using a sample having a predetermined size smaller than those measurement dimensions.

<About the division of each

part

55, 56, 57 of the absorption structure 17>
The division of each of the thick portion, the thickness gradient portion, and the

thin portions

55, 56, and 57 of the absorbent structure 17 can be performed by the following method, for example. In addition, the following method is based on the result calculated before debossing the absorbent structure 17 and based on the mass per unit area, not the thickness dimension of each part. This is because there is no change in the mass per unit area in each

portion

55, 56, 57 before and after the debossing process, and the mass per unit area varies depending on the thickness dimension as described above. This means that the

sections

55, 56, and 57 can be divided by such a method.

First, the absorbent structure 17 having a length dimension of about 360 mm in the longitudinal direction Y is divided into 18 sections every length dimension of about 20 mm in the longitudinal direction Y. Next, the mass (g / m ² ) per unit area for each divided section is measured. In each section, the mass value of the section with the highest mass per unit area is set to 1, and the ratio to the maximum mass value is calculated for each other section, and plotted in a table arranged in order from 1 to 18 sections. To do. Among the plotted points, the boundary on the thick side (the side with the higher percentage value relative to the maximum mass value) is the boundary point at which two points connecting the adjacent points on both sides are descending A point is a first boundary point that is a boundary between the thick part 55 and the thickness gradient part 56, and a boundary point on the thin side (the side having a lower ratio value with respect to the maximum mass value) is the thickness gradient part 56 and the thin part 57. The second boundary point that is the boundary of. Thereby, in the absorption structure 17, the region of the length dimension between each section representing each boundary point is the thickness gradient portion 56, and the thicker side than the section of the first boundary point is the thick portion 55, and the second boundary. The thin part 57 side from the point can be classified as the thin part 57.

<Second Embodiment>
Referring to FIG. 8, the differences from the first embodiment will be described. In the present embodiment, the arrangement pattern of the compression recesses 60 of the first debossed portion 61 is different from that of the second debossed portion 63. In the first debossed portion 61, the non-compressed portion where the compression recess 60 does not exist is not continuously formed in the vertical direction Y and the horizontal direction X. Therefore, in the first debossed portion 61, the rigidity of the thin portion 57 in all directions can be increased. As shown in the partially enlarged view of the arrangement pattern of the compression recesses 60, the first debossed portion 61 defines a plurality of non-compression regions 82 surrounded by the six compression recesses 60. The non-compressed area 82 is relatively flexible by being surrounded by the compression recess 60, and compared to the case where the compression recesses 60 are densely arranged as in the first embodiment, the wearer The cushioning property for the body can be improved.

<Third Embodiment>
Referring to FIGS. 9 and 10, the differences from the first embodiment will be described. In the present embodiment, the absorbent structure 17 has a first thick portion 55 </ b> A that extends from the front region 51 to the rear of the central portion 53. A thin portion 57 formed in the rear region 52, a thickness gradient portion 56 located between the first thick portion 55A and the thin portion 57, and the rear edge 17b of the thin portion 57 and the absorbent structure 17. 2nd thick part 55B located in between.

The second thick portion 55B has substantially the same thickness as the first thick portion 55A, or at least 1.1 times the thickness of the thin portion 57, and is a first debossed portion. 61 is not formed. As described above, the second thick portion 55B is formed on the rear end edge 17b side of the rear region 52 by the second thick portion 55B having a thickness dimension substantially equal to the first thick portion 55A. Body fluid that has not been sufficiently absorbed by the thin portion 57 can be absorbed and retained, and leakage of body fluid from the rear end edge 17b can be reliably prevented.

The absorbent structure 17 according to the present invention can be used not only for disposable diapers but also for various body fluid absorption treatment articles such as sanitary napkins, incontinence pads, and training pants. In addition to the materials described in the present specification, various known materials that are usually used in this type of field can be used for each component of the diaper 10 without limitation. Further, in the specification and claims of the present invention, the terms “first”, “second”, and “third” are merely used to distinguish similar elements, positions, and the like. .

The disclosure relating to the first invention described above can be summarized at least in the following matters.
An absorbent wearing article comprising a liquid-absorbent core having at least body fluid absorbency, having a longitudinal direction and a transverse direction perpendicular thereto, and interposed between a liquid-permeable top sheet and a liquid-impermeable back sheet In the absorption structure for the first end edge, the second end edge facing the first end edge in the longitudinal direction, the thick portion located on the first end edge side, and the thickness located on the second end edge side A thin portion having a thickness dimension smaller than that of the portion, and a thickness that is located between the thick portion and the thin portion and gradually decreases in thickness from the first edge side toward the second edge side. And a thin portion, the thickness gradient portion, and a portion of the thick portion adjacent to the thickness gradient portion are subjected to debossing to form a number of compression recesses. The said absorption structure characterized by the above-mentioned.

The first invention disclosed in the above paragraph 0056 can include at least the following embodiments.
(1) It further includes both side edges extending in the longitudinal direction between the first end edge and the second end edge and having a concave portion, and the debossing is performed from the second end edge to a part of the concave portion. It has been given up to.
(2) A first debossed portion in which a plurality of the compressed concave portions by the debossing are arranged is formed on the thin portion side of the thin portion and the thickness gradient portion, and the thickness gradient portion A second debossed portion in which a plurality of the compressed concave portions by the debossing are arranged is formed on the thick portion side and a part of the thick portion adjacent to the thickness gradient portion, and the first debossed portion The compression recesses in the processed part are arranged more densely than those in the second debossed part.
(3) The said absorption structure is comprised from the sheet | seat which has the liquid diffusibility which covers the said liquid absorbent core of the single layer extended continuously in the said vertical direction, and the said liquid absorbent core.
(4) The second debossed portion has a plurality of uncompressed areas defined by being surrounded by the plurality of compression recesses.
(5) In the absorbent structure, a mass per unit area of the liquid-absorbent core of the thick part is higher than a mass per unit area of the liquid-absorbent core of the thin part, and the thickness gradient In the part, the mass per unit area of the liquid-absorbent core varies depending on the gradient of the thickness dimension.
(6) having a first thick part located between the first edge and the thickness gradient part, and a second thick part extending outward in the longitudinal direction from the thin part, The thickness dimensions of the first thick part and the second thick part are substantially the same.

The disclosure relating to the second invention described above can be summarized at least in the following matters.
First and second edges, a thick part located on the first edge side, a thin part having a smaller thickness than the thick part located on the second edge side, and the thick part A thickness gradient portion that is positioned between the thin portion and gradually decreases in thickness from the first end edge toward the second end edge, and the thin portion and the thickness gradient portion And a portion of the thick part adjacent to the thickness gradient part is subjected to debossing to form a number of compression recesses, a front waist region, a rear waist region, and the front and rear waists A diaper body having a crotch region located between the regions, the absorbent structure extending from the front waist region to the rear waist region, and the first edge of the absorbent structure on the front waist region side Located, the second edge is located on the rear waist region side, the adjacent contact portion and the Absorbent wearing article is and the slope portion positioned in the crotch region.

10 Absorbent wearing articles (disposable diapers)
11 Front waist region 12 Rear waist region 13 Crotch region 14 Diaper body 15 Top sheet 16 Back sheet 17 Absorbent structure 17a First edge (front edge)
17b Second edge (rear edge)
17c, 17d Both side edges 55 Thick portion 55A First thick portion 55B Second thick portion 56 Thickness gradient portion 57 Thin portion 60 Compression recess 61 First debossed portion 63 Second debossed portion 64 High rigidity region 82 Compression area X Horizontal direction Y Vertical direction Z Thickness direction

Claims

An absorbent wearing article comprising a liquid-absorbent core having at least body fluid absorbency, having a longitudinal direction and a transverse direction perpendicular thereto, and interposed between a liquid-permeable top sheet and a liquid-impermeable back sheet In the absorbent structure for
A first end edge and a second end edge facing the first end edge in the longitudinal direction, a thick part located on the first end edge side, and a thickness dimension smaller than the thick part located on the second end edge side A thin portion, and a thickness gradient portion that is located between the thick portion and the thin portion and gradually decreases in thickness from the first end side toward the second end side,
The absorbent structure, wherein the thin portion, the thickness gradient portion, and a portion of the thick portion adjacent to the thickness gradient portion are subjected to debossing to form a number of compression recesses. .
It further includes both side edges extending in the longitudinal direction between the first edge and the second edge and having concave parts, and the debossing is performed from the second edge to a part of the concave parts. The absorbent structure according to claim 1.
A first debossed part in which a plurality of the compression recesses by the debossing are arranged is formed on the thin part side of the thin part and the thickness gradient part, and the thick part side of the thickness gradient part And a part of the thick part adjacent to the thickness gradient part is formed with a second debossed part in which a plurality of the compressed recesses by the debossing are arranged, in the first debossed part The absorbent structure according to claim 1 or 2, wherein the compression recesses are arranged more densely than those in the second debossed part.
The absorbent structure according to any one of claims 1 to 3, wherein the absorbent structure includes a single-layer liquid-absorbent core that extends continuously in the longitudinal direction and a sheet having liquid diffusibility that covers the liquid-absorbent core. The absorbent structure described.
The absorbent structure according to any one of claims 1 to 4, wherein the second debossed portion has a plurality of uncompressed regions defined by being surrounded by the plurality of compression recesses.
In the absorbent structure, a mass per unit area of the liquid absorbent core of the thick portion is higher than a mass per unit area of the liquid absorbent core of the thin portion, and in the thickness gradient portion The absorbent structure according to any one of claims 1 to 5, wherein a mass per unit area of the liquid-absorbent core varies depending on a gradient of its thickness dimension.
A first thick portion located between the first edge and the thickness gradient portion; and a second thick portion extending outward in the longitudinal direction from the thin portion, and The absorbent structure according to any one of claims 1 to 6, wherein a thickness dimension of the thick part and the second thick part is substantially the same.
First and second edges, a thick part located on the first edge side, a thin part having a smaller thickness than the thick part located on the second edge side, and the thick part A thickness gradient portion that is positioned between the thin portion and gradually decreases in thickness from the first end edge toward the second end edge, and the thin portion and the thickness gradient portion And a portion of the thick part adjacent to the thickness gradient part is subjected to debossing to form a number of compression recesses, a front waist region, a rear waist region, and the front and rear waists A diaper body having a crotch region located between the regions, the absorbent structure extending from the front waist region to the rear waist region, and the first edge of the absorbent structure on the front waist region side Located, the second edge is located on the rear waist region side, and the adjacent portion and the front Absorbent wearing article and thickness gradient portion is located in the crotch region.