CN111374835A

CN111374835A - Absorbent body for absorbent article and absorbent article

Info

Publication number: CN111374835A
Application number: CN201811640417.9A
Authority: CN
Inventors: 丹下悟; 高居义
Original assignee: Unicharm Corp
Current assignee: Unicharm Corp
Priority date: 2018-12-29
Filing date: 2018-12-29
Publication date: 2020-07-07
Anticipated expiration: 2038-12-29
Also published as: WO2020137432A1; CN111374835B; JP2020108752A

Abstract

Provided are an absorbent for an absorbent article and an absorbent article, which are excellent in the temporary storage of liquid and the transfer of liquid in the thickness direction. An absorbent (14) for an absorbent article, comprising a1 st absorbent layer (41) comprising a super absorbent polymer, a2 nd absorbent layer (42) comprising a super absorbent polymer, and an intermediate layer (43) comprising fibers disposed between the 1 st absorbent layer (41) and the 2 nd absorbent layer (42), and having a thickness direction (T) and a plane direction (P), characterized in that the intermediate layer (43) comprises a low fiber density portion (LD) having a relatively low fiber density and a high fiber density portion (HD) having a relatively high fiber density.

Description

Absorbent body for absorbent article and absorbent article

Technical Field

The present disclosure relates to an absorbent body for an absorbent article and an absorbent article.

Background

An absorbent body for an absorbent article is known, which includes a1 st absorbent layer containing a super absorbent polymer, a2 nd absorbent layer containing a super absorbent polymer, and a fabric layer disposed between the 1 st absorbent layer and the 2 nd absorbent layer.

For example, patent document 1 describes a water-absorbent sheet having a structure in which an absorbent layer containing a water-absorbent resin and an adhesive is sandwiched between hydrophilic nonwoven fabrics, wherein the water-absorbent sheet has a structure in which a water-absorbent layer containing a water-absorbent resin and an adhesive is sandwiched between hydrophilic nonwoven fabricsManufacturing: the absorptive layer is divided into 1 times absorptive layer and 2 times absorptive layer by a base material layer, the base material layer is formed by bonding and laminating more than two layers of base materials with air permeability by using bonding agents, the base material layer satisfies the following conditions (1) to (2), (1) the basis weight of the base material layer is 25g/m²And (2) utilizing 0.1g/m between the substrates having air permeability²～50g/m²The amount of the adhesive is the same as the amount of the adhesive.

In the water-absorbent sheet (absorbent body) described in patent document 1, the base layer is a member including: in an absorbent material having a high proportion of a water-absorbent resin (superabsorbent polymer), blocking of the water-absorbent resin (superabsorbent polymer) is suppressed, and a delay in the absorbency of the water-absorbent resin (superabsorbent polymer) is compensated for by temporarily storing liquid in a base material layer.

Documents of the prior art

Patent document

Patent document 1: international publication No. 2010/143635 pamphlet

Disclosure of Invention

Problems to be solved by the invention

In the water-absorbent sheet (absorbent body) described in patent document 1, the liquid that has reached the 1 st absorbent layer remains around the super absorbent polymer contained in the 1 st absorbent layer, and is difficult to transfer in the thickness direction, that is, to the substrate layer present on the garment side, and further to the 2 nd absorbent layer, and the substrate layer is difficult to temporarily store the liquid.

Accordingly, an object of the present disclosure is to provide an absorbent body for an absorbent article, which is excellent in the temporary storage property of liquid and the transferability of liquid in the thickness direction.

Means for solving the problems

The present inventors have proposed an absorbent body for an absorbent article, comprising a1 st absorbent layer containing a super absorbent polymer, a2 nd absorbent layer containing a super absorbent polymer, and an intermediate layer containing fibers disposed between the 1 st absorbent layer and the 2 nd absorbent layer, having a thickness direction and a plane direction, wherein the intermediate layer comprises a low fiber density portion having a relatively low fiber density and a high fiber density portion having a relatively high fiber density.

ADVANTAGEOUS EFFECTS OF INVENTION

The absorbent for an absorbent article of the present disclosure is excellent in the temporary storage of liquid and the transferability of liquid in the thickness direction.

Drawings

Fig. 1 is a front view of a pants-type diaper 1 of embodiment 1 in an unfolded state.

Fig. 2 is a rear view of the pants-type diaper 1 in an unfolded state.

Fig. 3 is a cross-sectional view of the pants-type diaper 1 along the line III-III of fig. 1.

Fig. 4 is a cross-sectional view of the absorbent body 14 taken along the line III-III in fig. 1.

Fig. 5 is a diagram for explaining the absorbent body 14.

Description of the reference numerals

1 pants-type diaper; 2 ventral portion (ventral waistband); 3 dorsal side (dorsal waistband); 4 crotch part; 5. 5a, 5b cover sheet; 10 an absorbent main body; 12 a liquid-permeable sheet; 13 a liquid-impermeable sheet; 14 an absorbent body; 41 the 1 st absorption layer; 42 a2 nd absorbent layer; 43 an intermediate layer; a 43S intermediate sheet; 43a No. 1 sheet portion; 43b No. 2 sheet portion; 43c a knurl portion; 44, a1 st substrate; 45, a1 st water absorbent material; 46 a2 nd substrate; 47 a2 nd water absorbent material; 48 channels; 103. 104 a fold axis; l length direction; the width direction of W; the thickness direction of T; CL length direction center line; a CW width direction center line; LB low basis weight region; HB high basis weight region; an OP overlapping part; an NP non-overlapping portion; an HD high fiber density section; LD low fiber density portion.

Detailed Description

Specifically, the present disclosure relates to the following technical solutions.

[ solution 1]

An absorbent body for an absorbent article, comprising a1 st absorbent layer containing a super absorbent polymer, a2 nd absorbent layer containing a super absorbent polymer, and an intermediate layer containing fibers disposed between the 1 st absorbent layer and the 2 nd absorbent layer, having a thickness direction and a plane direction,

the intermediate layer includes a low fiber density portion having a relatively low fiber density and a high fiber density portion having a relatively high fiber density.

Since the absorbent body includes the intermediate layer having a predetermined high fiber density portion, the high fiber density portion of the intermediate layer can absorb and temporarily store the liquid that reaches the 1 st absorbent layer and is retained around the 1 st absorbent material. In the high fiber density portion of the intermediate layer, the temporarily stored liquid may be moved to the low fiber density portion of the intermediate layer as the amount of the temporarily stored liquid increases, and then the low fiber density portion containing the liquid may transfer the liquid to the 2 nd absorbent layer in accordance with the need of the 2 nd absorbent layer. Therefore, the intermediate layer of the absorbent body is excellent in the temporary storage property of liquid and in the liquid transferability in the thickness direction.

[ solution 2]

The absorbent body according to claim 1, wherein the high fiber density portion extends in a predetermined direction within the plane direction.

In the absorbent body described above, since the high fiber density portion provided in the intermediate layer extends in a predetermined direction in the plane direction, the liquid that is sucked into and temporarily stored in the high fiber density portion of the intermediate layer can be diffused in the predetermined direction in the plane direction of the intermediate layer, and then the liquid diffused in the plane direction is easily transferred to the 2 nd absorbent layer in the thickness direction. Therefore, the absorbent body is excellent in liquid transferability in the thickness direction and the planar direction.

[ solution 3]

The absorbent body according to claim 1 or 2, wherein the intermediate layer includes a high basis weight region having a relatively high basis weight and a low basis weight region having a relatively low basis weight, and the high fiber density portion is disposed in the high basis weight region.

In the absorbent body, the high fiber density portion is disposed in the high basis weight region, and therefore the amount of fibers constituting the high fiber density portion is relatively large, and the high fiber density portion can absorb the liquid that reaches the 1 st absorbent layer and stays around the 1 st absorbent material, and further, can absorb the liquid into the intermediate layer and temporarily store the liquid. Further, the absorber is excellent in temporary storage property.

[ solution 4]

The absorbent body according to claim 3, wherein the intermediate layer is formed of an intermediate sheet folded in the thickness direction at a predetermined folding axis, the intermediate layer is divided into an overlapping portion where the intermediate sheet overlaps in the thickness direction and a non-overlapping portion where the intermediate sheet does not overlap in the thickness direction, and the high area-by-area-weight region is formed by the overlapping portion.

In the absorbent body, the intermediate layer is formed by the folded intermediate sheet, and the high basis weight region of the intermediate layer is formed by the overlapping portion. Therefore, when the high fiber density portion of the intermediate layer absorbs liquid, the overlapping portion constituting the high basis weight region can be expanded in the thickness direction with the folding axis as a base point, and therefore the high basis weight region (overlapping portion) of the intermediate layer can further temporarily store liquid, and the absorbent body is excellent in temporary storage property.

[ solution 5]

The absorbent body according to claim 4, wherein the high fiber density portion is an embossed portion obtained by embossing the overlapped portion.

In the absorbent body, the high fiber density portion is a predetermined embossed portion, and the superposed portions are connected by the embossed portion, so that the high fiber density portion (embossed portion) can suppress twisting of the absorbent body even when liquid is sucked into the high fiber density portion of the intermediate layer and the superposed portion in which the high fiber density portion is arranged is expanded in the thickness direction with the folding axis as a base point.

[ solution 6]

The absorber according to any one of claims 1 to 5, wherein the intermediate layer includes a skin side surface, and a fiber density in the intermediate layer is higher than a fiber density of the skin side surface.

In the absorbent body described above, the fiber density in the intermediate layer is higher than the fiber density on the skin side of the intermediate layer, and therefore, the liquid absorbed in the intermediate layer is easily transferred from the skin side to the inside of the intermediate layer and further to the clothing surface by capillary action, and further, the liquid transferred to the clothing surface of the intermediate layer is easily transferred to the 2 nd absorbent layer. Therefore, the absorbent body is excellent in liquid transferability in the thickness direction.

The skin-side surface of the intermediate layer, which has a relatively low fiber density, can retain the superabsorbent polymer contained in the 1 st absorbent layer in the gaps between the fibers, and the superabsorbent polymer is excellent in retention.

[ solution 7]

The absorbent body according to claim 6, wherein the intermediate layer is formed of an intermediate sheet having a1 st side with a relatively low fiber density and a2 nd side with a relatively high fiber density, and the intermediate sheet is folded at a predetermined folding axis with the 2 nd side as an inner surface.

In the absorbent article, the intermediate layer is formed by the intermediate sheet folded so that the 1 st surface having a relatively low fiber density is an outer surface and the 2 nd surface having a relatively high fiber density is an inner surface, and therefore, in addition to the effect of claim 6, the intermediate sheet can hold the super absorbent polymer of the 1 st absorbent layer and the super absorbent polymer of the 2 nd absorbent layer in the gaps between the fibers, and the super absorbent polymer is excellent in holding property.

[ solution 8]

The absorber according to any one of claims 1 to 7, wherein the absorber has a longitudinal direction and a width direction,

the 2 nd absorbent layer is provided with a pair of channels extending in the longitudinal direction and separated in the width direction such that a longitudinal center line of the absorbent body is positioned between the pair of channels,

the high fiber density portion overlaps with each of the pair of channels in the thickness direction.

In the absorbent body, the high fiber density portion of the intermediate layer overlaps the pair of channels of the 2 nd absorbent layer in the thickness direction. The pair of channels disposed in the 2 nd absorbent layer contribute to deformation guidance for forming the absorbent body and the absorbent article including the absorbent body into a three-dimensional shape starting from the pair of channels. In the absorbent body described above, since the high fiber density portion of the intermediate layer overlaps the pair of channels in the thickness direction, the liquid taken in by the high fiber density portion of the intermediate layer can be moved to the pair of channels of the 2 nd absorbent layer, and the liquid can be diffused to the 2 nd absorbent layer through the pair of channels. As described above, the absorbent body is excellent in deformation guidance and in liquid transferability in the thickness direction and the plane direction.

In addition, in the above-described absorbent body, the high fiber density portion of the intermediate layer overlaps with the pair of channels in the thickness direction, and therefore the wearer of the absorbent article does not easily feel a difference in rigidity at the pair of channels of the 2 nd absorbent layer.

[ solution 9]

An absorbent article comprising a liquid-permeable sheet, a liquid-impermeable sheet, and an absorbent body disposed between the liquid-permeable sheet and the liquid-impermeable sheet,

the absorber is the absorber described in any one of claims 1 to 8.

The absorbent article described above has the same effects as in claim 1 and the like.

Hereinafter, the absorbent body for an absorbent article of the present disclosure (hereinafter, sometimes referred to as "the absorbent body of the present disclosure") and the absorbent article will be described in detail. For the sake of simplifying the description, the absorbent body is also described in the embodiment of the absorbent article.

Fig. 1 to 5 are views for explaining an absorbent article, specifically, a pants-type diaper 1 according to one embodiment of the present disclosure (hereinafter, referred to as embodiment 1). Specifically, fig. 1 and 2 are a front view and a rear view of the pants-type diaper 1 in an unfolded state, respectively. Fig. 3 is a cross-sectional view of the pants-type diaper 1 along the line III-III of fig. 1. Fig. 4 is a cross-sectional view of the absorbent body 14 taken along the line III-III in fig. 1. Fig. 5 is a view for explaining the absorbent body 14, fig. 5 (a) is a plan view, and fig. 5 (b) is a cross-sectional view taken along line Vb-Vb in fig. 5 (a). The drawings are schematic, and particularly, for convenience of understanding, the thickness in the thickness direction T is drawn thicker than it is in reality in fig. 3 to 5.

The pants-type diaper 1 has a longitudinal direction L, a width direction W, and a thickness direction T which are orthogonal to each other in the state shown in fig. 1, and has a longitudinal direction center line CL which passes through the center in the width direction W and extends in the longitudinal direction L, and a width direction center line CW which passes through the center in the length direction L and extends in the width direction W. The direction and the side close to the longitudinal center line CL are set as the inward direction and the inward side in the width direction W, respectively, and the direction and the side away from the longitudinal center line CL are set as the outward direction and the outward side in the width direction W, respectively. The direction and the side closer to the width direction center line CW are set as the inward direction and the inward side in the longitudinal direction L, respectively, and the direction and the side farther from the width direction center line CW are set as the outward direction and the outward side in the longitudinal direction L, respectively.

The side of the pants-type diaper 1 facing the end edge of the wearer corresponding to the abdomen (end edge on the abdomen side) in the longitudinal direction L is also referred to as the front side in the longitudinal direction L, and the side of the pants-type diaper 1 facing the end edge of the wearer corresponding to the back (end edge on the back side) is also referred to as the back side in the longitudinal direction L.

The "plan view" refers to the pants-type diaper 1 in a state of being developed on a plane including the longitudinal direction L and the width direction W as viewed from above in the thickness direction T, and the "plan view" refers to a shape grasped in plan view.

The "planar direction" is an arbitrary direction parallel to a plane including the width direction W and the length direction L.

The "skin side" and the "non-skin side" refer to a side relatively close to the skin surface of the wearer and a side far from the skin surface of the wearer in the thickness direction T, respectively, in the case where the pants-type diaper 1 is worn on the wearer.

These definitions apply not only to the pants-type diaper 1 but also to the absorber of the pants-type diaper 1 and the respective materials disposed thereon.

The extension of the member, structure, shape, or the like (hereinafter referred to as "member or the like") in the longitudinal direction L includes not only the case where the member or the like is parallel to the longitudinal direction L but also the case where the component Dx in the longitudinal direction L of the member or the like is larger than the component Dy in the width direction W of the member or the like (Dx > Dy). Similarly, the term "the member or the like extends in the width direction W" includes not only a case where the member or the like is parallel to the width direction W but also a case where the component Dy in the width direction W of the member or the like is larger than the component Dx in the longitudinal direction L of the member or the like (Dy > Dx). For a member or the like having a shape such as a curve or a curved surface (hereinafter referred to as "curve or the like"), the member or the like is evaluated as described above with respect to a tangent line at each point on the curve or the like.

As shown in fig. 1 and 2, the pants-type diaper 1 has a plane direction P and a thickness direction T that are orthogonal to each other, and the plane direction P includes a longitudinal direction L and a width direction W of the pants-type diaper 1.

The pants-type diaper 1 includes a stomach-side portion (stomach-side waistband) 2, a back-side portion (back-side waistband) 3, and an absorbent main body 10 positioned between the stomach-side portion 2 and the back-side portion 3 in the longitudinal direction L. In embodiment 1, the pants-type diaper 1 further includes a crotch portion 4 located between the abdomen-side portion 2 and the back-side portion 3. The abdomen portion 2 is a portion that abuts against the abdomen of the wearer. The back portion 3 is a portion that abuts against the hip or the back of the wearer. The absorbent body 10 is a portion that comes into contact with the crotch of the wearer, and has one end portion in the longitudinal direction L stacked on the stomach-side portion 2 and the other end portion stacked on the back-side portion 3. The crotch portion 4 is a portion that supports the absorbent main body 10 from the non-skin side.

The pants-type diaper 1 is formed by joining both

end portions

2a, 2a in the width direction W of the abdomen-side portion 2 and both

end portions

3a, 3a in the width direction W of the back-side portion 3 along the longitudinal direction L. In the pants-type diaper 1, a waist opening through which the waist of the wearer passes is defined by an outer end 2e of the stomach-side portion 2 in the longitudinal direction L and an outer end 3e of the back-side portion 3 in the longitudinal direction L. In the pants-type diaper 1, a pair of leg openings through which the legs of the wearer pass are defined by the

side portions

5e, 5e on both sides in the width direction W of the crotch portion 4. The abdomen-side portion (abdomen-side waistband) 2 and the back-side portion (back-side waistband) 3 can be said to be defined by the range of the longitudinal direction L in which the both

end portions

2a, 2a and the both

end portions

3a, 3a are joined.

In embodiment 1, in the state shown in fig. 1 and 2, each of the ventral portion 2 and the dorsal portion 3 has a rectangular shape that expands substantially in the width direction W and is separated from each other in the longitudinal direction L. The crotch portion 4 is located between the stomach portion 2 and the back portion 3, and both side edges in the width direction W are recessed inward in the width direction W. The stomach-side portion 2, the crotch portion 4, and the back-side portion 3 are integrally formed with each other. In another embodiment (not shown), the stomach-side portion 2, the crotch portion 4, and the back-side portion 3 are formed independently of each other. In another embodiment (not shown), the pants-type diaper 1 includes a front side portion 2 and a back side portion 3, and does not include a crotch portion 4.

In embodiment 1, the stomach portion 2, the back portion 3, and the crotch portion 4 are provided with liquid-impermeable cover sheets (sheet members) 5. The cover sheet 5 includes a cover sheet 5a on the skin side and a cover sheet 5b on the non-skin side. The cover sheet 5a and the cover sheet 5b are laminated in the thickness direction T and bonded to each other with an adhesive or the like. Both ends in the longitudinal direction L of the covering sheet 5b are folded back toward the skin side so as to cover both ends in the longitudinal direction L of the covering sheet 5 a. The portion of the cover sheet 5b at the folded position of the abdomen portion 2 constitutes the end portion 2e of the abdomen portion 2, and the portion of the cover sheet 5b at the folded position of the back portion 3 constitutes the end portion 3e of the back portion 3.

In embodiment 1, the abdomen-side portion 2 is provided with a plurality of

elastic members

6a, 6b for waist gather between the covering sheet 5a and the covering sheet 5b, and the back-side portion 3 is provided with a plurality of

elastic members

7a, 7b for waist gather between the covering sheet 5a and the covering sheet 5 b. The plurality of

elastic members

6a and 6b are disposed inside and outside the abdominal portion 2 in the longitudinal direction L. The plurality of elastic members 6a are arranged in the longitudinal direction L along the width direction W in predetermined regions on both sides across the longitudinal center line CL at intervals. The predetermined region is a region from the end portion 2a to a portion inside the end edge facing in the width direction W of the absorbent main body 10. The plurality of elastic members 6b extend from the one end portion 2a to the other end portion 2a in the width direction W, and are arranged at intervals in the longitudinal direction L. Similarly, the plurality of

elastic members

7a and 7b are disposed inside and outside the back portion 3 in the longitudinal direction L.

The plurality of elastic members 7a are arranged in the longitudinal direction L along the width direction W in predetermined regions on both sides across the longitudinal center line CL at intervals from each other. The predetermined region is a region from the end portion 3a to a portion inside the end edge facing in the width direction W of the absorbent main body 10. The plurality of elastic members 7b extend from the one end portion 3a to the other end portion 3a in the width direction W and are arranged at intervals in the longitudinal direction L. The plurality of

elastic members

6a, 6b, 7a, and 7b are for extending and contracting the waist opening, and are exemplified by rubber bands. The abdomen-side portion (abdomen-side waistband) 2 and the back-side portion (back-side waistband) 3 may be defined by a range in the longitudinal direction L in which the plurality of

elastic members

6a, 6b, 7a, 7b are arranged.

In embodiment 1, the pants-type diaper 1 includes a plurality of elastic members 8 for leg gathers from the crotch portion 4 to the back portion 3 and the stomach portion 2. The plurality of elastic members 8 are provided extending in the longitudinal direction L mainly at both ends in the width direction W of the crotch portion 4. The plurality of elastic members 8 are for expanding and contracting the pair of leg openings, respectively, and are exemplified by rubber bands.

In embodiment 1, the absorbent body 10 has a substantially rectangular shape, and includes a liquid-permeable sheet 12, a liquid-impermeable sheet 13, and an absorbent body 14 disposed between the liquid-permeable sheet 12 and the liquid-impermeable sheet 13 and absorbing and retaining liquid such as urine. Examples of the liquid-permeable sheet 12 include a liquid-permeable nonwoven fabric, a woven fabric, a synthetic resin film having liquid-permeable holes formed therein, and a composite sheet thereof. Examples of the liquid-impermeable sheet 13 include liquid-impermeable nonwoven fabrics, synthetic resin films, and composite sheets thereof, such as SMS nonwoven fabrics.

In embodiment 1, the absorbent body 14 includes an absorbent core for absorbing and retaining liquid and a core cladding that encloses the absorbent core. The absorbent body 14 will be described in detail later. The absorbent body 14, the liquid-permeable sheet 12, and the liquid-impermeable sheet 13 are bonded together with an adhesive, and the liquid-permeable sheet 12 and the liquid-impermeable sheet 13 are bonded together with an adhesive at their peripheral edge portions. Examples of the adhesive include materials known in pants-type diapers, such as a hot melt adhesive. The shape of the absorbent main body 10 is not limited to the above examples as long as it is long in the longitudinal direction L, and examples thereof include a rectangular shape with rounded corners, a rectangular shape with a short side being a curve protruding outward, and an hourglass shape. In another embodiment, the liquid-impermeable sheet 13 is omitted, and the non-skin side surface of the absorbent body 14 and the non-skin side surface of the peripheral edge portion of the liquid-permeable sheet 12 are joined to the cover sheet 5.

In embodiment 1, the skin-side surface of the absorbent main body 10 includes a pair of

side sheets

17, 17 located on both sides in the width direction W and extending in the longitudinal direction L. Each side sheet 17 has a leakage preventing wall 16 and

fastening regions

15, 15. The

fastening regions

15, 15 are positioned at the front and rear ends of the side sheet 17 in the longitudinal direction L and are fastened to the skin-side surface of the absorbent main body 10. The leakage preventing wall 16 is positioned between the front and

rear fixing regions

15, 15 in the longitudinal direction L of the side sheet 17, is adjacent to them, and the outer end edge in the width direction W of the leakage preventing wall 16 is fixed to the skin-side surface of the absorbent main body 10, while the inner end edge in the width direction W of the leakage preventing wall 16 is not fixed. The leakage preventing walls 16 and the

fastening regions

15, 15 are formed by, for example, inner portions of the side sheets 17 in the width direction W, and outer portions of the side sheets 17 in the width direction W are fastened to the absorbent main body 10.

The pair of

leakage preventing walls

16, 16 are disposed so as to face each other at both end portions in the width direction W on the skin side of the absorbent main body 10, and extend continuously along the longitudinal direction L. Each of the leakage preventing walls 16 includes two elastic members 61 extending in the longitudinal direction L at inner ends in the width direction W. The elastic member 61 is exemplified as a rubber band. The pair of

leakage preventing walls

16, 16 are each formed of a hydrophobic sheet, such as a hydrophobic nonwoven fabric. In another embodiment, the pair of

leakage preventing walls

16, 16 are each formed of a hydrophilic sheet, such as a hydrophilic nonwoven fabric.

Next, the absorbent body 14 will be described with reference to fig. 1 to 5. The absorber 14 includes a1 st absorbent layer 41 disposed on the skin side, a2 nd absorbent layer 42 disposed on the non-skin side, and an intermediate layer 43 disposed between the 1 st absorbent layer 41 and the 2 nd absorbent layer 42. The absorbent body 14 has a substantially rectangular planar shape extending in the longitudinal direction L.

In embodiment 1, the 1 st absorbent layer 41 includes a1 st base 44 formed of a liquid-permeable sheet and a1 st absorbent material 45 having a water-absorbent material containing a water-absorbent polymer and disposed on the intermediate layer 43 side of the 1 st base 44. The 1 st absorbent layer 41 can be viewed as having the 1 st absorbent material 45 as the absorbent core portion, and the 1 st substrate 44 (and intermediate layer 43) as the core cladding. The 1 st water absorbent material 45 is fixed to at least one of the 1 st base material 44 and the intermediate layer 43 by an adhesive applied to at least one of the surface of the 1 st base material 44 on the intermediate layer 43 side and the surface of the intermediate layer 43 on the 1 st base material 44 side.

The water absorbing material of the 1 st water absorbing material 45 is disposed in the 1 st absorbing layer 41 with a substantially uniform basis weight. The 1 st water absorbing material 45 has a substantially rectangular planar shape. The 1 st base material 44 has a substantially rectangular planar shape, and covers the 1 st absorbent material 45 from the skin side in plan view, and the peripheral edge portion of the 1 st base material 44 extends slightly outward from the periphery of the 1 st absorbent material 45.

In embodiment 1, the 2 nd absorbent layer 42 includes a2 nd base 46 formed of a sheet having water retentivity and liquid diffusibility, and a2 nd water-absorbent material 47 having a water-absorbent material containing a water-absorbent polymer and disposed at a position closer to the intermediate layer 43 than the 2 nd base 46. The 2 nd absorbent layer 42 can be viewed as having the 2 nd water absorbent material 47 as the absorbent core portion and the 2 nd base material 46 (and intermediate layer 43) as the core cladding. The 2 nd water absorbing material 47 is fixed to at least one of the 2 nd base material 46 and the intermediate layer 43 with an adhesive applied to at least one of the surface of the 2 nd base material 46 on the intermediate layer 43 side and the surface of the intermediate layer 43 on the 2 nd base material 46 side. The absorbent material of the 2 nd absorbent material 47 is disposed in the 2 nd absorbent layer 42 with a substantially uniform basis weight except for the pair of channels 48, 48 (described later).

The 2 nd water absorbing material 47 has a substantially rectangular planar shape one turn larger than the 1 st water absorbing material 45 in the width direction W and the length direction L. The 2 nd base material 46 has a substantially rectangular planar shape, and covers the 2 nd absorbent material 47 from the non-skin side in plan view, and the peripheral edge portion of the 2 nd base material 46 extends slightly outward from the periphery of the 2 nd absorbent material 47. Both ends of the 2 nd base material 46 in the width direction W cover both side surfaces of the 2 nd absorbent 47, and cover the skin-side surfaces of both ends of the 1 st base material 44 in the width direction W. That is, on the skin-side surface of the end portion in the width direction W of the 1 st absorbent layer 41, the end portion in the width direction W of the 2 nd base material 46 and the end portion in the width direction W of the 1 st base material 44 are overlapped and joined.

Both ends in the width direction W of the 2 nd base 46 cover the side surfaces in the width direction W of the 2 nd water absorbent 47 and cover the side surfaces in the width direction W of the 1 st base 44, whereby the 2 nd water absorbent 47 is enclosed in the 2 nd absorbent layer 42 in the width direction W and the 1 st water absorbent 45 is enclosed in the 1 st absorbent layer 41 in the width direction W.

In embodiment 1, the 1 st base material 44, the intermediate layer 43, and the 2 nd base material 46 are laminated and joined in the thickness direction T at both ends in the longitudinal direction L of the absorbent body 14. Thus, the 1 st water absorbent material 45 is enclosed in the 1 st absorbent layer 41 by the 1 st base material 44 and the intermediate layer 43 in the longitudinal direction L, and the 2 nd water absorbent material 47 is enclosed in the 2 nd absorbent layer 42 by the 2 nd base material 46 and the intermediate layer 43 in the longitudinal direction L.

In embodiment 1, the intermediate layer 43 has a substantially rectangular planar shape in plan view, and includes a low area weight region LB having a relatively low weight per unit area and a pair of high area weight regions HB having a relatively high weight per unit area. Specifically, the intermediate layer 43 includes a pair of high basis weight regions HB disposed at both ends in the width direction W and a low basis weight region LB disposed at the center in the width direction W.

The intermediate layer 43 is formed of a single liquid-permeable intermediate sheet 43S (specifically, a through-air nonwoven fabric including sheath-core composite fibers). The intermediate sheet 43S includes two

folding axes

103, 104, and is divided into a1 st sheet portion 43a disposed inside the two

folding axes

103, 104 and a pair of 2

nd sheet portions

43b, 43b disposed outside the two

folding axes

103, 104 in the unfolded state. The intermediate layer 43 is formed by folding a single intermediate sheet 43S in the thickness direction T, specifically, to the 2 nd absorbent layer 42 side, according to two

folding axes

103, 104 extending in the longitudinal direction L.

In the intermediate layer 43, the single intermediate sheet 43S is folded along the two

folding axes

103 and 104, and the pair of 2

nd sheet portions

43b and 43b are disposed on both sides in the width direction W of the 1 st sheet portion 43a in the plane direction P, and the pair of 2

nd sheet portions

43b and 43b are disposed on the 2 nd absorbent layer 42 side in the thickness direction T. The portions of the 1 st sheet portion 43a and each 2 nd sheet portion 43b of the pair of 2

nd sheet portions

43b, 43b that overlap in the thickness direction T constitute a pair of overlapping portions OP of the intermediate layer 43, and the portions of the 1 st sheet portion 43a that do not overlap with the pair of 2

nd sheet portions

43b, 43b in the thickness direction T constitute non-overlapping portions NP. Each overlapping portion OP of the pair of overlapping portions OP coincides with each high basis weight region HB of the pair of high basis weight regions HB, and the non-overlapping portion NP coincides with the low basis weight region LB.

In the intermediate layer 43, at a pair of high area weight regions HB (a pair of overlapping portions OP), the 1 st sheet portion 43a and the 2 nd sheet portion 43b are joined by a pair of embossed portions 43c extending in the longitudinal direction L.

In the intermediate layer 43, the fiber density of the composite fibers at the pair of embossed portions 43c is higher than the fiber density of the composite fibers at the portions other than the pair of embossed portions 43 c.

In other words, the intermediate layer 43 is divided into a pair of high fiber density portions HD formed by the pair of embossed

portions

43c and 3 low fiber density portions LD formed by portions other than the pair of embossed portions 43 c.

The pair of high fiber density portions HD extend in the longitudinal direction L and are arranged at predetermined intervals on both sides in the width direction W with respect to the longitudinal center line CL.

The pair of high fiber density portions HD tend to cause the liquid that has reached the 1 st absorbent layer 41 to accumulate around the 1 st absorbent material 45 of the 1 st absorbent layer 41, but the liquid that has accumulated around the 1 st absorbent material 45 can be drawn into the pair of high fiber density portions HD (the pair of embossed portions 43c) and further into the intermediate layer 43 by capillary action.

Further, since the pair of high fiber density portions HD extend in the longitudinal direction L, the liquid sucked into the pair of high fiber density portions HD is easily diffused in the longitudinal direction L in the intermediate layer 43. Next, the liquid diffused in the longitudinal direction L in the intermediate layer 43 is easily transferred to the 2 nd absorbent layer 42.

The pair of high fiber density portions HD are disposed in the pair of high basis weight regions HB (the pair of overlapping portions OP). Therefore, the amount of the composite fibers constituting the high fiber density portion HD is relatively large, and the liquid retained around the 1 st water-absorbent material 45 can be sucked into the pair of high fiber density portions HD (the pair of embossed portions 43c) by capillary action, and further, the liquid can be sucked into the intermediate layer 43 and temporarily stored.

In the intermediate layer 43, the intermediate sheet 43S includes a web surface (not shown) that comes into contact with the web (placement surface) when the air-through nonwoven fabric is formed, and a non-web surface (not shown) on the side opposite to the web. The web side has a relatively high fiber density compared to the non-web side. Since the intermediate sheet 43S is folded with the web surface on the inner side, the intermediate layer 43 is configured such that the fiber density inside the intermediate layer 43 is higher than the fiber density on the skin-side surface.

Therefore, the liquid sucked into the intermediate layer 43 is easily transferred from the skin-side surface of the intermediate layer 43 to the inside, and further to the clothing surface (not shown), and further, the liquid transferred to the clothing surface of the intermediate layer 43 is easily transferred to the 2 nd absorbent layer 42 by the capillary phenomenon. The skin-side surface (non-net surface) of the intermediate layer 43, which has a relatively low fiber density, can hold the 1 st water-absorbent material 45 contained in the 1 st absorbent layer 41, and has excellent retention of the super absorbent polymer.

The pair of high area-unit-weight regions HB are formed by a pair of overlapping portions OP in which the 1 st sheet portion 43a and the 2 nd sheet portion 43b are laminated in the thickness direction T. The 1 st sheet portion 43a and the 2 nd sheet portion 43b are not joined together except at the pair of embossed portions 43c and the two

folding axes

103, 104, and therefore, in the case where the liquid is sucked in the pair of high fiber density portions HD of the intermediate layer 43, the pair of overlapping portions OP constituting the pair of high area weight regions HB can be expanded in the thickness direction T with the two

folding axes

103, 104 and the pair of embossed portions 43c as base points, and therefore the pair of high area weight regions HB (the pair of overlapping portions OP) of the intermediate layer 43 can further temporarily store the liquid.

The pair of high fiber density portions HD are formed by an embossed portion 43c obtained by embossing the 1 st sheet portion 43a and the 2 nd sheet portion 43b, and the 1 st sheet portion 43a and the 2 nd sheet portion 43b are joined together at the embossed portion 43 c.

Therefore, even when the liquid is sucked into the pair of high fiber density portions HD of the intermediate layer 43 and the pair of superposed sections OP on which the pair of high fiber density portions HD are arranged is expanded in the thickness direction T with the two

folding axes

103, 104 as base points, the pair of high fiber density portions HD (embossed sections 43c) can suppress twisting of the absorbent body 14.

The intermediate layer 43 has both end edges in the width direction W sandwiched between and bonded to both end portions in the width direction W of the 1 st base material 44 and the 2 nd base material 46, and has both end edges in the length direction L of the intermediate layer 43 sandwiched between and bonded to both end portions in the length direction L of the 1 st base material 44 and the 2 nd base material 46.

The absorbent body 14 has a pair of

channels

48, 48 extending along the length direction L. The pair of

passages

48, 48 are strip-shaped regions that are disposed in the 2 nd absorption layer 42, extend in the longitudinal direction L, and are arranged at predetermined intervals on both sides in the width direction W with a longitudinal center line CL therebetween. The channel 48 is disposed at least in the central portion in the longitudinal direction L of the 2 nd absorption layer 42 so as to cross the width-direction center line CW.

Each of the channels 48 of the pair of

channels

48, 48 is a region in which the weight per unit area of the 2 nd water absorbent material 47 is smaller than the region around each of the channels 48 of the pair of

channels

48, 48. Each channel 48 of the pair of

channels

48, 48 is formed such that the 2 nd base material 46 is recessed toward the intermediate layer 43 side, that is, such that the 2 nd water absorbing material 47 is recessed toward the intermediate layer 43 side.

Each of the pair of

channels

48, 48 is arranged so as to overlap with the pair of high area-per-area-weight regions HB (the pair of overlapping portions OP) of the intermediate layer 43 in the thickness direction T.

In addition, the pair of

passages

48, 48 are arranged so as to overlap the pair of embossed portions 43c in the thickness direction T, in other words, each high fiber density portion HD of the pair of high fiber density portions HD overlaps each passage 48 of the pair of

passages

48, 48 in the thickness direction T. This allows the liquid absorbed by the pair of high fiber density portions HD of the intermediate layer 43 to move to the pair of

channels

48, 48 of the 2 nd absorbent layer 42, and the liquid to diffuse into the 2 nd absorbent layer 42 through the pair of

channels

48, 48.

The 1 st water absorbing material 45 and the 2 nd water absorbing material 47 contain Super Absorbent Polymers (SAP). The basis weight of the super absorbent polymer of each of the 1 st water absorbent material 45 and the 2 nd water absorbent material 47 can be appropriately adjusted in accordance with the absorption performance required for the pants-type diaper 1, but for example, each of them is 10g/m²～500g/m²Preferably 100g/m²～400g/m²。

The basis weights of the 1 st water-absorbing material 45 and the 2 nd water-absorbing material 47 may be larger in one than in the other, or may be the same. Wherein, the same means that one is in the range of 100% + -30% of the other. The 1 st water-absorbing material 45 and the 2 nd water-absorbing material 47 may further have hydrophilic fibers such as water-absorbing fibers (e.g., pulp fibers). The proportion of the super absorbent polymer in the 1 st water absorbent material 45 and the 2 nd water absorbent material 47 is, for example, 80 to 100% by mass, preferably 90 to 100% by mass, and more preferably 95 to 100% by mass.

Therefore, the 1 st water-absorbent material 45 and the 2 nd water-absorbent material 47 can be said to contain a super absorbent polymer as a main component, and the absorbent body 14 can be said to be a so-called SAP sheet.

The proportion of the super absorbent polymer in the absorbent body 14 (including not only the 1 st and 2 nd water

absorbent materials

45 and 47 but also the adhesive, the 1 st base 44, the intermediate layer 43, and the 2 nd base 46) is, for example, 40 to 80% by mass, preferably 50 to 80% by mass, and more preferably 60 to 80% by mass.

In embodiment 1, the 1 st water absorbing material 45 and the 2 nd water absorbing material 47 are each formed of only a super absorbent polymer and do not contain hydrophilic fibers.

Preferably, 90 to 100 mass% of the superabsorbent polymer is composed of superabsorbent polymer particles having a particle diameter of 150 to 500 μm. The superabsorbent polymer particles having the above particle diameter have a small and uniform particle diameter and are therefore easily retained in the adhesive. The particle diameter of the super absorbent polymer particles is measured in accordance with JIS R6002: the screening test method described in 1998 was standard.

The adhesive is not particularly limited as long as it can fix the super absorbent polymer, and examples thereof include a hot melt adhesive. The pattern of the adhesive to be applied is not particularly limited, but examples thereof include a continuous or intermittent Ω pattern, a spiral pattern, and a line pattern. The basis weight of the adhesive can be appropriately adjusted so as not to significantly reduce the liquid absorbency of the absorbent body 14, and each layer is, for example, 3g/m²～50g/m². Here, each layer means a layer of the adhesive between the 1 st water absorbent material 45 and the 1 st base 44, a layer of the adhesive between the 1 st water absorbent material 45 and the intermediate layer 43, a layer of the adhesive between the 2 nd water absorbent material 47 and the 2 nd base 46, and a layer of the adhesive between the 2 nd water absorbent material 47 and the intermediate layer 43.

The 1 st base material 44 is not particularly limited as long as it is a liquid-permeable sheet. Examples of the 1 st substrate 44 include a liquid-permeable nonwoven fabric containing synthetic fibers, a hydrophilic nonwoven fabric, and a laminated nonwoven fabric thereof, and among them, a nonwoven fabric having high water permeability is preferable. Examples of the 1 st base material 44 include a spun-bonded nonwoven fabric and a hot-air nonwoven fabric formed of polyolefin fibers such as Polyethylene (PE) and polypropylene (PP), polyester fibers such as polyethylene terephthalate (PET), polytrimethylene terephthalate (PTT) and polyethylene naphthalate (PEN), or a combination thereof.

The synthetic fibers are preferably hydrophilized by a known method.

The liquid-permeable sheet may be, for example, an air-laid nonwoven fabric in which hydrophilic fibers such as pulp fibers and rayon fibers are covered with a hydrophilic binder, or a nonwoven fabric in which the hydrophilic fibers and the synthetic fibers are combined, such as a spunlace nonwoven fabric. In embodiment 1, an air-laid nonwoven fabric in which pulp fibers are coated with a hydrophilic binder and which has liquid permeability and liquid retention properties is used.

The 1 st substrate 44 may be formed by laminating one or more kinds of the nonwoven fabrics.

The unit area weight of the No. 1 substrate 44 is, for example, 10g/m²～100g/m²Preferably 20g/m²～80g/m². The thickness of the 1 st substrate 44 is, for example, 0.1mm to 5mm, preferably 0.15mm to 3 mm.

The 2 nd substrate 46 is not particularly limited as long as it is a sheet having water retentivity and liquid diffusibility. Examples of the 2 nd base 46 include nonwoven fabrics formed of synthetic fibers such as polyamide fibers, regenerated fibers such as rayon fibers and acetate fibers, natural fibers such as cotton, silk, hemp and pulp (cellulose) fibers, or a combination thereof. Specifically, the 2 nd substrate 46 may be, for example, a spun-bonded nonwoven fabric containing nylon, a spun-laced nonwoven fabric containing rayon fibers and/or pulp fibers, or the like. The spunlace nonwoven containing rayon fibers and/or pulp fibers may also contain polyolefin fibers and/or polyester fibers. In embodiment 1, a spunlace nonwoven fabric containing rayon fibers and pulp fibers, which has liquid retention and liquid diffusion properties, is used.

The 2 nd substrate 46 may be formed of one of the nonwoven fabrics, or may be formed by laminating a plurality of nonwoven fabrics.

The basis weight of the No. 2 substrate 46 is, for example, 10g/m²～200g/m²Preferably 35g/m²～150g/m². The thickness of the 2 nd substrate 46 is, for example, 0.1mm to 5mm, preferably 0.15mm to 3 mm.

The intermediate layer 43 (intermediate sheet 43S) is, for example, a sheet similar to the 1 st substrate 44. The weight per unit area of the intermediate layer 43 is, for example, 10g/m²～100g/m²Preferably 15g/m²～80g/m². The thickness of the intermediate layer 43 is, for example, 0.1mm to 5mm, preferably 0.15mm to 3 mm.

In embodiment 1, as shown in fig. 5, the absorber 14 includes a back-side region BA, a stomach-side region FA, and a crotch region MA which are arranged in the longitudinal direction L. Here, the back-side area BA is an area of the absorbent body 14 that overlaps with the back-side portion 3 in the thickness direction T. The abdomen-side region FA is a region of the absorbent body 14 that overlaps the abdomen-side portion 2 in the thickness direction T. The crotch region MA is a region of the absorber 14 between the back-side region BA and the stomach-side region FA, i.e., a region overlapping with the crotch portion 4 in the thickness direction T. Thus, the absorber 14 is divided into a back-side region BA overlapping the back-side portion 3, a stomach-side region FA overlapping the stomach-side portion 2, and a crotch region MA overlapping the crotch portion 4 along the longitudinal direction L.

In embodiment 1, the absorbent body 14 includes SAP high area weight regions 14a, SAP low area weight regions 14b, and SAP non-arrangement regions 14 c. The SAP high basis weight region 14a is a region in which the basis weight of the super absorbent polymer is relatively high, and is a region in which the 1 st absorbent layer 41 and the 2 nd absorbent layer 42 overlap in the thickness direction T. The SAP low basis weight region 14b is a region in which the basis weight of the super absorbent polymer is relatively low, and is a region in which the 1 st absorbent layer 41 is not present and only the 2 nd absorbent layer 42 is present in the thickness direction T. The SAP non-arrangement region 14c is a region not containing a super absorbent polymer, and is a region where the 1 st absorption layer 41 and the 2 nd absorption layer 42 are not present in the thickness direction T. The term "not containing a super absorbent polymer" includes the case where the weight per unit area of the super absorbent polymer is very small although the super absorbent polymer is present. "very small" means that the weight per unit area of the super absorbent polymer is 5% or less of the weight per unit area of the super absorbent polymer in the SAP high weight per unit area region 14 a.

Thus, in the absorbent body 14, the back-side area BA includes back-side SAP high-area-weight areas BAa as the SAP high-area-weight areas 14a, back-side SAP low-area-weight areas BAb as the SAP low-area-weight areas 14b, and back-side SAP non-arrangement areas barc as the SAP non-arrangement areas 14 c. In the absorbent body 14, the abdominal region FA includes the abdominal SAP high unit area weight region FAa as the SAP high unit area weight region 14a, the abdominal SAP non-arrangement region FAc as the SAP non-arrangement region 14c, and the abdominal SAP low unit area weight region FAb is not included. The crotch region MA has only the SAP high area weight region 14 a.

Therefore, the basis weight of the superabsorbent polymer in the back-side SAP high basis weight region BAa and the stomach-side SAP high basis weight region FAa is equivalent to the basis weight of the superabsorbent polymer in the crotch region MA. "equivalent" means that one is in the range of 0.7 to 1.3 times (100% ± 30%) the other.

The 2 nd absorbent layer 42 includes a protruding portion protruding outward from the end edge of the 1 st absorbent layer 41 at the rear end in the longitudinal direction L in plan view. The protrusion includes a backside SAP low-area-weight region BAb, which is the same as the backside SAP low-area-weight region BAb. The 2 nd absorption layer 42 is covered with the intermediate layer 43, and thus the skin side of the protruding portion, i.e., the back-side SAP low-area-weight area BAb, is covered with the intermediate layer 43 and the 1 st base material 44.

In the absorber 14, db2> dc2> da2 when the length of the back-side SAP high area weight region BAa, the length of the back-side SAP low area weight region BAb, and the length of the back-side SAP non-arrangement region barc are da2, db2, and dc2, respectively, in the longitudinal direction L. That is, in the back-side area BA, the length of the back-side SAP low-area-weight area BAb is made relatively long, the weight per unit area of the super absorbent polymer is suppressed to be low as a whole, and the super absorbent polymer is arranged in the rear portion in the longitudinal direction L. It is possible to easily suppress the transmission leakage of the liquid that flows to the back side although the amount is small.

In the absorber 14, da1> dc1 where da1 represents the length of the abdominal-side SAP high basis weight region FAa and dc1 represents the length of the abdominal-side SAP non-arrangement region FAc in the longitudinal direction L. That is, in the abdomen-side region FA, the length of the abdomen-side SAP high basis weight region FAa is made relatively long, the basis weight of the super absorbent polymer is increased as a whole, and the super absorbent polymer is arranged at the front end in the longitudinal direction L. This makes it possible to reliably absorb the liquid on the abdominal side with a large amount of excretion.

In the absorber 14, dc2> dc1 in the longitudinal direction L. The length of the back-side SAP non-disposition region barc can be made relatively long, the amount of the super absorbent polymer used in the back-side region BA with a small amount of excretion can be suppressed to be low, and the length of the abdomen-side SAP non-disposition region FAc can be made relatively short, so that the liquid in the abdomen-side region FA with a large amount of excretion can be reliably absorbed.

In addition, in another embodiment, da2+ db2> da1 in the longitudinal direction L in the absorber 14. In this case, by disposing the super absorbent polymer in the back-side area BA further to the rear side in the longitudinal direction L, it is possible to more easily suppress the transmission leakage of the liquid flowing to the back side although the amount is small.

Next, a method for producing the absorbent body 14 will be described.

First, the sheet for the 2 nd substrate 46 is moved in the longitudinal direction L, and the hot melt adhesive is applied onto the sheet for the 2 nd substrate 46. Next, a super absorbent polymer was sprayed from a super absorbent polymer supply device onto both end portions and a central portion in the width direction W of the sheet for the 2 nd substrate 46 coated with the hot melt adhesive along the length direction L, respectively. At this time, a small amount of the super absorbent polymer is transferred to the region (corresponding to the channel) between the both end portions and the central portion. Next, a sheet for the intermediate layer 43 coated with hot melt adhesive on both sides was laminated on the super absorbent polymer on the sheet for the 2 nd substrate 46.

Next, the laminate was moved in the longitudinal direction L, and a super absorbent polymer was sprayed from another super absorbent polymer supply device in the longitudinal direction L onto the central portion in the width direction W of the sheet for the intermediate layer 43 coated with the hot melt adhesive. Next, the sheet for the 1 st substrate 44 coated with the hot melt adhesive was laminated on the super absorbent polymer on the sheet for the intermediate layer 43 so that the hot melt adhesive was located on the super absorbent polymer side. Then, both side portions in the width direction W of the sheet for the 2 nd base material 46 were folded back onto both side portions in the width direction W of the sheet for the 1 st base material 44 to obtain a laminate. After that, the thickness of the laminate is adjusted by passing the laminate through a pair of press rolls, i.e., pressing, to obtain the absorbent body 14.

Next, a method for manufacturing a pants-type diaper using the absorbent body 14 will be described.

A liquid-permeable sheet 12 is attached to the upper surface (the surface of the 1 st base 44) of the absorbent body 14 produced as described above, and a liquid-impermeable sheet 13 is attached to the lower surface (the surface of the 2 nd base 46) of the absorbent body 14, thereby obtaining a laminate. Next, the side sheets 17 with the leakage preventing walls 16 are attached to both sides in the width direction W of the laminate to obtain the absorbent main body 10. Thereafter, the absorbent body 10 is attached to the cover sheet 5 (including the elastic members 6, 7, and 8), and both

ends

2a and 2a in the width direction W of the abdomen-side portion 2 and both

ends

3a and 3a in the width direction W of the back-side portion 3 are joined. Thereby, the pants-type diaper 1 is manufactured.

The absorbent article including the absorbent body of the present disclosure is not particularly limited, and examples thereof include disposable diapers, incontinence pads, disposable pants, sanitary napkins, pants-type sanitary napkins, pantiliners, mattress pads, breast pads, hemorrhoid pads, sweat absorbing pads, bedsore sheets (wound repair sheets), pet diapers, and pet sheets.

In the absorbent body of the present disclosure, the intermediate layer contains fibers, and includes a low fiber density portion having a relatively low fiber density and a high fiber density portion having a relatively high fiber density. This allows the high fiber density portion of the intermediate layer to absorb the liquid that has reached the 1 st absorbent layer and has accumulated around the 1 st absorbent material.

The high fiber density portion preferably has a fiber density of 1.2 times or more, more preferably 1.5 times or more, further preferably 2.0 times or more, and further preferably 3.0 times or more, the fiber density of the low fiber density portion. This is from the viewpoint of the above-described effects. The high fiber density portion preferably has a fiber density of 50 times or less, more preferably 40 times or less, and still more preferably 30 times or less, the fiber density of the low fiber density portion. This is for the wearer not to feel stiffness at the high fiber density portion.

When the high fiber density portion and the low fiber density portion have the same weight per unit area, the high fiber density portion preferably has a height of 1/1.2 times (about 0.83 times) or less, more preferably 1/1.5 times (about 0.67 times) or less, still more preferably 1/2.0 times (0.5 times) or less, and still more preferably 1/3.0 times or less the height of the low fiber density portion. This is from the viewpoint of the above-described effects. The high fiber density portion preferably has a thickness of 1/50 times (0.020 times) or more, more preferably 1/40 times (0.025 times) or more, and still more preferably 1/30 times (about 0.033 times) or more the thickness of the low fiber density portion. This is for the wearer not to feel stiffness at the high fiber density portion.

The thickness of the high fiber density portion and the thickness of the low fiber density portion were measured by a three-dimensional X-ray CT apparatus (TDM-1000-IS/SP manufactured by Daohuaku corporation). Specifically, the thickness of a desired density portion (high fiber density portion or low fiber density portion) is measured at arbitrary 20 points in an image obtained by scanning using a three-dimensional measurement X-ray CT apparatus, and the thickness of the desired density portion is determined by taking an average.

The high fiber density portion preferably extends in a predetermined direction in the plane direction, and preferably extends in the longitudinal direction of the absorbent body. This is because the liquid taken in by the high fiber density portion of the intermediate layer can be diffused in a predetermined direction, particularly in the longitudinal direction, in the plane direction of the intermediate layer, and then the liquid diffused in the plane direction is easily transferred in the thickness direction, that is, to the 2 nd absorbent layer.

In the absorbent body of the present disclosure, the intermediate layer may include a low basis weight region having a relatively low basis weight and a high basis weight region having a relatively high basis weight in the planar direction. In this case, the high fiber density portion is preferably disposed in a high basis weight region. This is because the amount of the fibers constituting the high fiber density portion is relatively large, and the high fiber density portion can suck the liquid that reaches the 1 st absorbent layer and stays around the 1 st absorbent material, and further, can suck the liquid into the intermediate layer and temporarily store the liquid.

In the absorbent body of the present disclosure, it may be that the intermediate layer is formed of an intermediate sheet folded in the thickness direction of the absorbent body at a predetermined folding axis, the intermediate layer being divided into an overlapping portion where the intermediate sheet overlaps in the thickness direction of the absorbent body and a non-overlapping portion where the intermediate sheet does not overlap in the thickness direction of the absorbent body. In this case, the high basis weight region may be formed by an overlapping portion or a non-overlapping portion, and is preferably formed by an overlapping portion. By forming the high basis weight region with the overlapping portion, when the high fiber density portion of the intermediate layer sucks in the liquid, the overlapping portion constituting the high basis weight region can be expanded in the thickness direction with the fold axis as a base point, and therefore the high basis weight region (overlapping portion) of the intermediate layer can further temporarily store the liquid.

In addition, from the viewpoint that the overlapped portion can be expanded in the thickness direction, it is preferable that the portions of the intermediate sheet constituting the overlapped portion are not fixed to each other except for the high area weight region.

In the absorbent body of the present disclosure, the intermediate layer (intermediate sheet) having the high fiber density portion and the low fiber density portion is not particularly limited, and an intermediate layer known in the art can be used. For example, a nonwoven fabric having a high fiber density portion and a low fiber density portion can be produced according to the descriptions of japanese patent application laid-open nos. 2008-138340, 2008-144322, 2008-264084, 2008-266813, and the like.

The intermediate layer (intermediate sheet) having the high fiber density portion and the low fiber density portion includes a nonwoven fabric having convex portions (for example, raised portions) and concave portions (for example, groove portions) having different weights per unit area, and specifically, a nonwoven fabric having convex portions (for example, raised portions) constituting the high fiber density portion and concave portions (for example, groove portions) constituting the low fiber density portion. Such nonwoven fabrics can be produced according to the descriptions of japanese patent application laid-open nos. 2008-002034 and 2008-023311.

Further, an intermediate layer (intermediate sheet) having a high fiber density portion and a low fiber density portion can also be formed by gear-drawing the nonwoven fabric.

Further, the intermediate layer (intermediate sheet) having the high fiber density portion and the low fiber density portion may be formed by compressing, for example, embossing (forming embossed portions) in the thickness direction of the folded intermediate sheet or the unfolded intermediate sheet.

In the absorbent body of the present disclosure, the fiber density in the thickness direction of the intermediate layer can be arbitrary, and for example, can be low on the skin side and high on the garment side, and can be low on the skin side and the garment side and high on the inside.

In the absorbent body of the present disclosure, the intermediate layer may include a skin side surface, and the fiber density in the intermediate layer may be higher than the fiber density on the skin side surface. This makes it easy to transfer the liquid absorbed in the intermediate layer from the skin-side surface to the inside of the intermediate layer and further to the clothing surface by utilizing the capillary phenomenon, and further makes it easy to transfer the liquid transferred to the clothing surface of the intermediate layer to the 2 nd absorbent layer.

In the absorbent body of the present disclosure, the intermediate layer may be formed of an intermediate sheet having a1 st surface with a relatively low fiber density and a2 nd surface with a relatively high fiber density, and the intermediate sheet may be disposed such that the 1 st surface with a low fiber density is the skin side and the 2 nd surface with a high fiber density is the garment side. This makes it easy to transfer the liquid that has reached the intermediate layer to the 2 nd absorbing layer by capillary action.

In the absorbent body of the present disclosure, the intermediate layer may be formed of an intermediate sheet having a1 st surface with a relatively low fiber density and a2 nd surface with a relatively high fiber density, wherein the intermediate sheet is folded at a predetermined folding axis with the 2 nd surface as an inner surface. This makes it easy to transfer the liquid that has reached the intermediate layer to the 2 nd absorbent layer by capillary action, and the intermediate sheet can hold the super absorbent polymer of the 1 st absorbent layer and the super absorbent polymer of the 2 nd absorbent layer.

The intermediate sheet having the 1 st surface having a relatively low fiber density and the 2 nd surface having a relatively high fiber density includes, for example, a nonwoven fabric produced on a web. For example, in the case of a through-air nonwoven fabric, a web is placed on a web and structural fibers are fused together to form the nonwoven fabric. In this case, the web side in contact with the web has a relatively high fiber density and constitutes the 2 nd side, while the non-web side not in contact with the web has a relatively low fiber density and constitutes the 1 st side.

In the absorbent body of the present disclosure, the intermediate sheet constituting the intermediate layer may be folded toward the liquid-impermeable sheet. This makes it difficult to form a gap between the sheet member adjacent to the liquid-permeable sheet side of the intermediate layer and the intermediate layer, and the intermediate layer easily receives the liquid that has reached the liquid-permeable sheet from the sheet member.

In the absorbent body of the present disclosure, the 1 st absorbent layer and the 2 nd absorbent layer each contain a super absorbent polymer. The super absorbent polymer is not particularly limited, and includes super absorbent polymers known in the art, and examples thereof include starch-based, cellulose-based, and synthetic polymer-based super absorbent polymers. Examples of the starch-based or cellulose-based super absorbent Polymer include a starch-acrylic acid (salt) graft copolymer, a saponified product of a starch-acrylonitrile copolymer, and a crosslinked product of sodium carboxymethylcellulose, examples of the synthetic Polymer-based super absorbent Polymer include super absorbent polymers (SAP, super absorbent Polymer) such as polyacrylate, polysulfonate, maleic anhydride, polyacrylamide, polyvinyl alcohol, polyethylene oxide, polyaspartate, polyglutamate, polyalphaelate, starch, and cellulose, and the like, and a polyacrylate (particularly, sodium polyacrylate) is preferable.

In the absorbent body of the present disclosure, as long as the 1 st and 2 nd absorbent layers each mainly contain a super absorbent polymer, there is no particular limitation, and hydrophilic fibers such as pulp fibers may be further contained. The shape of the absorbent body in plan view is not particularly limited, and examples thereof include a rectangle having a short side projecting in an arc shape, a rounded rectangle, an ellipse, and an hourglass shape. The thickness of the absorbent body is, for example, 0.5mm to 20mm, preferably 1mm to 10 mm.

In the absorbent body of the present disclosure, a channel can be included. The channels can be disposed in the 1 st absorption layer and/or the 2 nd absorption layer. This makes it easy to guide the deformation of the absorbent body and thus the absorbent article when the absorbent article is worn. From this viewpoint, the passage preferably extends in the longitudinal direction, and more preferably, the pair of passages extends in the longitudinal direction such that the longitudinal center line is located between the pair of passages.

In addition, the above-mentioned channel (a pair of channels) is preferably disposed in the 2 nd absorption layer. This is from the viewpoint of ease of deformation guidance of the absorbent article.

The pair of channels may be arranged such that, for example, the interval between the pair of channels is constant in the longitudinal direction of the absorbent body in plan view, or may be arranged such that the interval between the pair of channels is narrow, for example, in the vicinity of the center in the longitudinal direction of the absorbent article, and expands toward both outer sides in the longitudinal direction.

The channels (a pair of channels) may be disposed in the 2 nd absorbent layer, and the channels (a pair of channels) may be disposed so as to overlap with the high fiber density portion of the intermediate layer in the thickness direction of the absorbent body. This allows the liquid absorbed by the high fiber density portion of the intermediate layer to move to the channel of the 2 nd absorbent layer, and the liquid to diffuse into the 2 nd absorbent layer through the channel.

In the absorbent body of the present disclosure, the channel (pair of channels) refers to a region in which the absorbent core has a smaller weight per unit area than the surrounding region of the 1 st absorbent layer and/or the 2 nd absorbent layer, which are the absorbent layers in which the channel is disposed. The channels (a pair of channels) preferably have a weight per unit area of 70 mass% or less, more preferably 50 mass% or less, and even more preferably 30 mass% or less, and may have a weight per unit area of 0 mass% as compared with the area around the 1 st and/or 2 nd absorbent layers, which are the absorbent layers in which the channels are arranged. This is from the viewpoint of using the channel as a starting point for the deformation guide.

Claims

1. An absorbent body for an absorbent article, comprising a1 st absorbent layer containing a super absorbent polymer, a2 nd absorbent layer containing a super absorbent polymer, and an intermediate layer containing fibers disposed between the 1 st absorbent layer and the 2 nd absorbent layer, having a thickness direction and a plane direction,

2. The absorbent body according to claim 1, wherein,

the high fiber density portion extends in a predetermined direction within the plane direction.

3. The absorbent body according to claim 1 or 2, wherein,

the intermediate layer includes a high basis weight region having a relatively high basis weight and a low basis weight region having a relatively low basis weight, and the high fiber density portion is disposed in the high basis weight region.

4. The absorbent body according to claim 3, wherein,

the intermediate layer is formed of an intermediate sheet folded in the thickness direction at a predetermined folding axis, the intermediate layer is divided into an overlapping portion where the intermediate sheet overlaps in the thickness direction and a non-overlapping portion where the intermediate sheet does not overlap in the thickness direction, and the high area weight region is formed by the overlapping portion.

5. The absorbent body according to claim 4, wherein,

the high fiber density portion is an embossed portion obtained by embossing the overlapping portion.

6. The absorbent body according to claim 1 or 2, wherein,

the intermediate layer has a skin side surface, and the fiber density inside the intermediate layer is higher than the fiber density of the skin side surface.

7. The absorbent body according to claim 6, wherein,

the intermediate layer is formed of an intermediate sheet having a1 st surface with a relatively low fiber density and a2 nd surface with a relatively high fiber density, and the intermediate sheet is folded at a predetermined folding axis with the 2 nd surface as an inner surface.

8. The absorbent body according to claim 1 or 2, wherein,

the absorbent body has a longitudinal direction and a width direction,

9. An absorbent article comprising a liquid-permeable sheet, a liquid-impermeable sheet, and an absorbent body disposed between the liquid-permeable sheet and the liquid-impermeable sheet,

the absorbent body according to any one of claims 1 to 8.