JP7323997B2 - absorbent article - Google Patents

Description

The present invention relates to absorbent articles having an intermediate sheet between the topsheet and the absorbent element. In particular, the intermediate sheet has a plurality of protrusions projecting from the back side toward the skin side and recesses formed between adjacent protrusions, and the recesses of the intermediate sheet penetrate the intermediate sheet in the thickness direction. The present invention relates to an absorbent article having through holes.

BACKGROUND ART Absorbent articles provided with an intermediate sheet between a top sheet provided on the skin side and an absorbent element provided on the back side are manufactured and sold. This intermediate sheet has the function of diffusing the excreted fluid in the planar direction. At the same time, it also has the function of preventing the excreted liquid absorbed by the absorbent element from returning to the top sheet under the influence of body pressure or the like.

Patent documents relating to the present invention include, for example, those described in Patent Documents 1 to 3 below.
The absorbent product of Patent Document 1 includes a perforated hydrophobic surface sheet formed in a pleated shape so as to have a large number of peaks and valleys formed between adjacent peaks, and the valleys of the top sheet. and a hydrophilic layer bonded to the underside of the topsheet so as to contact only the

The absorbent article of Patent Document 2 includes a liquid-permeable surface layer, a liquid-impermeable back layer, an absorbent core interposed therebetween, and an absorbent core interposed between the liquid-permeable surface layer and the absorbent core. The liquid-permeable surface layer is a sheet made of nonwoven fabric, part or all of this sheet has multi-row ridges and grooves alternately combined, and the grooves are spaced apart. A large number of openings are provided at intervals of .

In the absorbent article of Patent Document 3, a transfer sheet is laid between the surface material and the absorbent body in order to allow urine and the like to quickly permeate the absorbent body, and folds are formed in the transfer sheet.

Japanese Patent Application Laid-Open No. 2001-231815 Japanese Patent Application Laid-Open No. 09-299402 JP-A-2002-291796

A conventional intermediate sheet uses a lofty nonwoven fabric to prevent reversion from the absorbent element to the topsheet. When a bulky nonwoven fabric is used, even if the excreted fluid moves from the absorbent element to the skin side, the possibility of retaining the excreted fluid inside the intermediate sheet increases, and as a result, the excreted fluid reaches the top sheet. It becomes difficult to go back.

However, when a bulky non-woven fabric is used for the intermediate sheet, there is a problem that the bulky intermediate sheet inhibits rapid movement of the excreted liquid to the absorbent element in the process of transferring excreted liquid from the surface sheet to the absorbent element during excretion. There is Furthermore, during excretion, the amount of excreted fluid retained inside the intermediate sheet increases in the process of moving the excreted fluid from the surface sheet to the absorbent element. There is also the problem that the excrement retained inside is more likely to return to the topsheet.

On the other hand, if a low-bulk non-woven fabric is used for the intermediate sheet, when the excreted liquid moves from the absorbent element to the skin side, it is less likely that the excreted liquid can be retained inside the intermediate sheet, and backflow occurs. There is the problem of ease. Further, if the volume of the intermediate sheet is low, the distance in the thickness direction between the topsheet and the absorbent element is short, which also causes the problem that reversion is likely to occur.

The absorbent product of Patent Literature 1 relates to a perforated hydrophobic surface sheet that is pleated to have peaks and valleys, and does not relate to a so-called intermediate sheet. Further, in the absorbent article of Patent Document 2, in the liquid-permeable surface layer (sheet made of nonwoven fabric), ridges and grooves are formed in the sheet, and a large number of openings are provided in the grooves. , so-called intermediate sheets. That is, the above Patent Documents 1 and 2 relate to the surface sheet, and do not attempt to solve the above-mentioned problems of the intermediate sheet, and are fundamentally different from the present invention including their effects.

Although the absorbent article of Patent Document 3 relates to a pleated transfer sheet, it does not solve the problem of the present invention of rapidly transferring excretions such as urine to the absorbent element.

Accordingly, an object of the present invention is to provide an absorbent article that allows excretions such as urine to quickly reach an absorbent element during excretion and prevents the excreted liquid absorbed by the absorbent element from returning to the surface sheet. .

Various aspects of the tape-type disposable diaper that solves the above problems are as follows.
<First Aspect>
An absorbent article comprising a top sheet provided on the skin side, an absorbent element provided on the back side of the top sheet, and an intermediate sheet provided between the top sheet and the absorbent element,
The intermediate sheet has a plurality of convex portions protruding from the back side toward the skin side and concave portions formed between the adjacent convex portions,
An absorbent article, wherein a through hole (intermediate hole) penetrating through the intermediate sheet in the thickness direction is formed in the concave portion of the intermediate sheet.

(Effect)
By providing the intermediate sheet with protrusions and recesses, the distance in the thickness direction between the top sheet and the absorbent element is increased. As a result, it is possible to reduce the possibility that the excreted liquid retained by the absorbent element will return to the top sheet, compared to the case where the intermediate sheet has no protrusions or recesses.

Further, by forming a through-hole penetrating in the thickness direction in the concave portion of the intermediate sheet, it is possible to allow the excreted liquid to quickly reach the absorbent element during excretion. Excreted fluid that moves from the top sheet to the intermediate sheet collects in the recessed portions of the intermediate sheet, and since the recessed portions are formed with through-holes, the excreted liquid collected in the recessed portions quickly transfers to the absorbent element.

<Second Aspect>
The absorbent article according to the first aspect, wherein in the concave portion of the intermediate sheet, the peripheral portion of the through-hole has a higher fiber density than the non-peripheral portion.

(Effect)
When body pressure or the like is applied to the intermediate sheet (for example, when the crotch portion of the absorbent article is sandwiched between the wearer's legs), the high fiber density at the peripheral edge of the through-hole causes the peripheral edge to be compressed. Since the rigidity is increased, the shape of the convex portion is less likely to collapse. That is, if the peripheral edge of the through-hole is not hard, body pressure tends to deform the shape of the convex portion. The shape can be maintained. In order to harden the periphery of the through-hole, for example, if a bar-shaped steel material is inserted into the intermediate sheet, burrs are generated around the through-hole and the periphery becomes hard. In addition, the periphery of the through-hole may be hardened by, for example, inserting a rod-shaped steel material while heating it.

<Third Aspect>
The top sheet has a basis weight of 10 to 18 g/m ² ,
The top sheet has a fineness of 1.8 to 3.0 dtex,
The top sheet has a thickness of 0.1 to 0.3 mm,
The absorbent article according to the first or second aspect.

(Effect)
Since there is a contact point in the portion of the top sheet that is in contact with the convex portion of the intermediate sheet, excreted liquid from the top sheet easily moves to the intermediate sheet. However, in the areas of the top sheet that are not in contact with the convex portions of the intermediate sheet, it is difficult for the excreted liquid to move to the intermediate sheet, and the excreted liquid stays in the top sheet (liquid retention), so the top sheet becomes wet ( not dry), which may cause discomfort to the wearer. Since excreted fluid tends to accumulate in the recessed portions of the intermediate sheet, the portion where the top sheet is particularly likely to become wet is the portion overlapping the recessed portions of the intermediate sheet in a plan view.

The basis weight of the top sheet is preferably 10-18 g/m ² , more preferably 13-15 g/m ² . In addition, the thickness of the top sheet is preferably 0.1 to 0.3 mm, more preferably 0.2 to 0.3 mm. In addition, the fineness of the fibers constituting the top sheet is preferably 1.8 to 3.0 dtex, more preferably 2.0 to 2.5 dtex.

When the basis weight of the top sheet is greater than 18 g/m ² , the thickness of the top sheet is greater than 0.3 mm, and the fineness of the fibers constituting the top sheet is greater than 3.0 dtex, the top sheet retains excrement. There is a problem that the top sheet loses its smoothness. Therefore, by setting the basis weight of the top sheet to 18 g/m ² or less, the thickness of the top sheet to 0.3 mm or less, and the fineness of the fibers constituting the top sheet to 3.0 dtex or less, the aforementioned problem, that is, the top It is possible to solve the problem that the sheet becomes wet (not dry) and the wearer feels uncomfortable.

On the other hand, if the basis weight of the top sheet is less than 10 g/m ² or the thickness of the top sheet is less than 0.1 mm, the material strength of the top sheet is weakened, and the top sheet may be torn during use or uneven texture may occur. There is another problem that the excreted fluid tends to return to the skin surface side.

In addition, when the fineness of the fibers constituting the top sheet is smaller than 1.8 dtex, there is another problem that the excreted liquid is difficult to permeate from the top sheet to the back side.

Therefore, by setting the basis weight of the top sheet to 10 g/m ² or more, the thickness of the top sheet to 0.1 mm or more, and the fineness of the fibers constituting the top sheet to 1.8 dtex or more, the above problems can be solved. You can also

<Fourth Aspect>
In the artificial urine dropping test, the top sheet has a first measurement result of 10 points or less, a second measurement result of 5 points or less, and a third measurement result of 5 points or less. The absorbent article according to any one of the first to third aspects.

(Effect)
In order to solve the problem described in the third aspect, when the wearer excretes on the topsheet, at least a part of the hydrophilic agent contained in the topsheet flows down to the absorbent element together with the excreted liquid. preferably. By adopting such a mode, the amount of the hydrophilic agent contained in the top sheet is reduced during the second and subsequent excretion (because the top sheet changes from hydrophilic to hydrophobic), The top sheet does not retain liquid easily, and the smooth feeling of the top sheet is easily secured.

When selecting a top sheet that satisfies these conditions, the following artificial urine drop test is performed. The first measurement result is 10 points or less, the second measurement result is 5 points or less, and the third measurement result is 5 points or less. It is preferable to use a top sheet that gives 5 points or less for the absorbent article. This is because, when the wearer excretes a number of times, the hydrophilic agent tends to run off from the top sheet, and the top sheet is less likely to retain liquid. The number and thickness of layers of the top sheet used in the drip test of artificial urine, the material of the fiber of the top sheet, the manufacturing method, etc. are all the same as the top sheet actually mounted on the absorbent article. do.

The drip test of artificial urine is performed according to the following procedures (1) to (4).
<Drip test of artificial urine>
(1) The top sheet is placed on 10 layers of filter paper, and a metal jig with 10 holes is placed on the top sheet.
(2) Using a micropipette, 1 mL of artificial urine was dropped into each of the 10 holes of the metal jig, and the top sheet absorbed the artificial urine within 2 seconds after dropping. A hole that has been absorbed is counted as 1 point and a hole that is not absorbed as 0 point, and the total score of the 10 holes is recorded as the result of the first measurement.
(3) After 3 minutes have passed since the artificial urine was dripped in (2), 1 mL of artificial urine was dripped into each of the 10 holes of the metal jig using a micropipette, and then dripped. After that, within 2 seconds, check whether the top sheet has absorbed the artificial urine, count the absorbed holes as 1 point and the unabsorbed holes as 0 points, and count the total of 10 holes. Record the score as the result of the second measurement.
(4) After 3 minutes have passed since the artificial urine was dripped in (3), 500 μL of artificial urine was dripped into each of the 10 holes of the metal jig using a glass pipette and dripped. After that, within 2 seconds, check whether the top sheet has absorbed the artificial urine, count the absorbed holes as 1 point and the unabsorbed holes as 0 points, and count the total of 10 holes. Record the score as the result of the third measurement.

The artificial urine used in the artificial urine drip test contains 2 wt% urea, 0.8 wt% sodium chloride, 0.03 wt% calcium chloride dihydrate, 0.08 wt% magnesium sulfate heptahydrate, ion 97.09 wt% of exchange water is mixed.

The metal jig used for the artificial urine drip test was a rectangle with a width of 210 mm, a length of 50 mm, and a thickness of 5 mm. are provided at regular intervals with a space between them, and the weight is 400 g.

<Fifth Aspect>
The top sheet has a through hole (top hole) that penetrates the top sheet in the thickness direction,
The absorbent article according to any one of the first to fourth aspects, wherein the position of the top sheet where the through hole (top hole) is formed and the position of the concave portion of the intermediate sheet overlap in plan view.

(Effect)
In order to solve the problem described in the third aspect, it is preferable to provide the top sheet with through-holes so that excreted fluid can easily permeate from the skin side to the back side of the top sheet. As a result, the top sheet becomes less likely to retain the excreted liquid, and the dry feeling of the top sheet can be ensured. In addition, since the top sheet is not in contact with the intermediate sheet at the portion overlapping the concave portion of the intermediate sheet in plan view, the top sheet tends to be particularly wet. Therefore, by arranging the positions of the through-holes of the top sheet and the positions of the recesses of the intermediate sheet to overlap each other in plan view, it is possible to effectively prevent the top sheet from becoming wet.

<Sixth Aspect>
The diameter of the through hole (top hole) formed in the top sheet is larger than the diameter of the through hole (intermediate hole) formed in the intermediate sheet,
In plan view, the through holes (top holes) formed in the top sheet and the through holes (intermediate holes) formed in the intermediate sheet at least partially overlap.
The absorbent article according to the fifth aspect.

(Effect)
When the through-holes (top holes) formed in the top sheet and the through-holes (intermediate holes) formed in the intermediate sheet at least partly overlap in plan view, the excreted fluid quickly reaches the absorbent element. can be made However, in the actual manufacturing of absorbent articles, it is difficult to align the positions of the top hole and the intermediate hole so as to overlap each other in plan view. Therefore, it is preferable to make this alignment easier by making the diameter of the top hole larger than the diameter of the intermediate hole. It is also possible to consider a mode in which the diameter of the intermediate hole is made larger than the diameter of the top hole. However, since the intermediate sheet is provided with a convex portion, there is a restriction on increasing the diameter of the intermediate hole. Therefore, it is preferable to increase the diameter of the top hole.

The diameter of the top hole is preferably 2 to 4 times larger than the diameter of the intermediate hole, more preferably 2.5 to 3.5 times larger. If it is smaller than 2 times, the number of overlapped top holes and intermediate holes is reduced in plan view, and the area of the overlapped portion between the top holes and intermediate holes is reduced, so that excreted liquid reaches the absorbent element. It is difficult to obtain the effect of quickly reaching the target (as a matter of course, the greater the number of overlapping parts and the larger the area of the overlapping portion, the more likely the above-mentioned effect is obtained. The same applies hereinafter). If it is larger than 4 times, there is a problem that it becomes difficult to form and maintain the opening.

For example, if the diameter of the intermediate hole is 0.3-1 mm, the diameter of the top hole is preferably 0.6-4 mm.
When the shape of the top hole (and/or intermediate hole) is not circular in plan view, for example, when it is elliptical or polygonal such as square, the projected circle equivalent diameter (top hole (and/or intermediate hole) ) is the diameter of a circle equal to the projected area of ).
Moreover, the diameter of the top hole refers to the average value of the diameters of all the top holes provided within an arbitrary area (100 mm×100 mm square) of the top sheet. Similarly, the diameter of intermediate holes refers to the average value of the diameters of all intermediate holes provided within an arbitrary portion (100 mm×100 mm square) of the intermediate sheet. At this time, the position of the square on the top sheet and the position of the square on the intermediate sheet are made to completely overlap in plan view. In addition, it is preferable to select a portion that abuts on the wearer's excretory opening as the arbitrary portion of the top sheet or the intermediate sheet.
In order to allow the entire absorbent element to absorb excreted liquid, it is preferable that the positions of the top holes be uniform in the longitudinal and transverse directions of the top sheet. For the same reason, it is preferable that the intermediate holes are provided evenly in the vertical and horizontal directions of the intermediate sheet.

<Seventh Aspect>
The number of through holes (top holes) formed in the top sheet is greater than the number of through holes (intermediate holes) formed in the intermediate sheet,
In plan view, the through holes (top holes) formed in the top sheet and the through holes (intermediate holes) formed in the intermediate sheet at least partially overlap.
The absorbent article according to the fifth or sixth aspect.

(Effect)
When the through-holes (top holes) formed in the top sheet and the through-holes (intermediate holes) formed in the intermediate sheet at least partly overlap in plan view, the excreted fluid quickly reaches the absorbent element. can be made However, in the actual manufacturing of absorbent articles, it is difficult to align the positions of the top hole and the intermediate hole so as to overlap each other in plan view. Therefore, it is preferable to make the number of top holes larger than the number of intermediate holes to facilitate this alignment. It is also possible to consider a mode in which the number of intermediate holes is greater than the number of top holes. However, since the intermediate sheet is provided with protrusions, there is a restriction on increasing the number of intermediate holes. Therefore, it is preferable to increase the number of top holes.

The number of top holes is preferably 2 to 4 times the number of intermediate holes, more preferably 2.5 to 3.5 times. If it is less than 2 times, the number of overlapping top holes and intermediate holes is reduced in plan view, and the area of the overlapping portion of the top holes and intermediate holes is reduced, so that the excrement reaches the absorbent element. It is difficult to obtain the effect of quickly reaching the target. If it is more than 4 times, there is a problem that it becomes difficult to form and hold the openings, or the strength becomes weak.

For example, when the number of intermediate holes is 9-12/cm ² , the number of top holes is preferably 27-36/cm ² .
Further, the number of top holes refers to the number of top holes provided within an arbitrary area (100 mm×100 mm square) of the top sheet. Similarly, the number of intermediate holes refers to the number of intermediate holes provided within an arbitrary area (100 mm×100 mm square) of the intermediate sheet. At this time, the position of the square on the top sheet and the position of the square on the intermediate sheet are made to completely overlap in plan view. In addition, it is preferable to select a portion that abuts on the wearer's excretory opening as the arbitrary portion of the top sheet or the intermediate sheet.
In order to absorb the excreted liquid in the entire absorbent element, it is preferable that the positions of the top holes are uniform in the longitudinal direction and the lateral direction of the top sheet. For the same reason, it is preferable that the intermediate holes are provided evenly in the vertical and horizontal directions of the intermediate sheet.

ADVANTAGE OF THE INVENTION According to this invention, excretory fluids, such as urine, can be made to reach an absorption element rapidly at the time of excretion. At the same time, it is possible to prevent the excreted liquid absorbed by the absorbent element from returning to the surface sheet.

Fig. 2 is a plan view showing the inner surface of the tape-type disposable diaper when the diaper is unfolded; Fig. 2 is a plan view showing the outer surface of the tape-type disposable diaper when the diaper is unfolded; 6 is a cross-sectional view taken along line 6-6 of FIG. 1; FIG. In addition, the cross section of a part of the top sheet is enlarged and shown. FIG. 7 is a cross-sectional view taken along line 7-7 of FIG. 1; (a) A cross-sectional view taken along line 8-8 of FIG. 1, and (b) a cross-sectional view taken along line 9-9 of FIG. 4 is a plan view of an intermediate sheet; FIG. FIG. 7 is a cross-sectional view taken along line 2-2 of FIG. 6; Besides the middle sheet, the top sheet and the wrapping sheet are also shown. (a) It is a top view of the intermediate sheet of another form. (b) is a plan view of a top sheet superimposed on the intermediate sheet of (a) of FIG. 8; FIG. 9 is a cross-sectional view taken along line 3-3 of FIG. 8 ; A wrapping sheet is also shown, as well as a topsheet and an intermediate sheet. FIG. 11 is a plan view of another form of intermediate sheet; (a) It is a top view of a metal jig. (b) It is a perspective view of a metal jig. It is an enlarged cross-sectional view of the vicinity of the intermediate hole. 1 is a perspective view of an instrument used in Experimental Example 1. FIG. FIG. 4 is a plan view showing a case where the diameter of the top hole is larger than the diameter of the intermediate hole; (a) A mode in which the intermediate hole completely overlaps the top hole, and (b) a mode in which the intermediate hole partially overlaps the top hole. FIG. 4 is a plan view showing a case where the number of top holes is greater than the number of intermediate holes; (a) A mode in which the intermediate hole completely overlaps the top hole, and (b) a mode in which the intermediate hole partially overlaps the top hole.

1 to 5 exemplify tape-type disposable diapers as absorbent articles, where X in the figures indicates the total width of the diaper excluding the connecting tape, and L indicates the total length of the diaper. there is Also, although not shown, the top sheet 30, the intermediate sheet 40, the packaging sheet 58, the absorbent body 56, the liquid impermeable sheet 11 and the exterior nonwoven fabric 12 are each bonded with a hot melt adhesive. The hot melt adhesive is applied by known methods such as slot coating, continuous line or dotted line bead coating, spiral or Z-shaped spray coating, or pattern coating (transfer of hot melt adhesive by letterpress method). can be applied. Alternatively or additionally, at the fixing portion of the elastic member, a hot melt adhesive can be applied to the outer peripheral surface of the elastic member to fix the elastic member to the adjacent member. Hot-melt adhesives include, for example, EVA-based, adhesive rubber-based (elastomer-based), olefin-based, and polyester-polyamide-based adhesives, and can be used without particular limitation. As a joining means for joining each constituent member, a means by material welding such as heat sealing or ultrasonic sealing can be used.

This tape-type disposable diaper has an abdominal portion F extending forward from the center in the front-rear direction LD and a back portion B extending rearward from the center in the front-rear direction LD. In addition, this tape-type disposable diaper includes an absorbent body 56 built in a region including the crotch portion, a liquid-permeable top sheet 30 covering the front side of the absorbent body 56, and a liquid-impermeable top sheet 30 covering the back side of the absorbent body 56. It has a sheet 11 and an exterior nonwoven fabric 12 that covers the back side of the liquid-impermeable sheet and constitutes the outer surface of the product.

The materials and characteristic parts of each part will be described in order below.
(Absorber)
The absorbent body 56 is a part that absorbs and retains the excreted fluid, and can be formed by an assembly of fibers. The filament assembly may be a filament assembly obtained by laminating short fibers such as cotton pulp or synthetic fibers, or by opening tows (fiber bundles) of synthetic fibers such as cellulose acetate as necessary. can also be used. The fiber basis weight can be, for example, about 100 to 300 g/m ² when piling up cotton-like pulp or short fibers, and for example, about 30 to 120 g/m ² for filament aggregates. can be done. The fineness of synthetic fibers is, for example, 1 to 16 dtex, preferably 1 to 10 dtex, more preferably 1 to 5 dtex. In the case of a filament assembly, the filaments may be non-crimped fibers, but crimped fibers are preferred. The degree of crimping of the crimped fibers can be, for example, about 5 to 75, preferably 10 to 50, more preferably 15 to 50 per 2.54 cm. Further, uniformly crimped crimped fibers can be used.

(superabsorbent polymer particles)
Absorbent body 56 may contain superabsorbent polymer particles in part or in its entirety. Superabsorbent polymer particles include "powder" in addition to "particles". As the superabsorbent polymer particles, those used in this type of absorbent article can be used as they are. Although the particle size of the superabsorbent polymer particles is not particularly limited, for example, sieving using a 500 μm standard sieve (JIS Z8801-1: 2006) (shaking for 5 minutes), and particles falling under the sieve in this sieving When sieving (shaking for 5 minutes) using a 180 μm standard sieve (JIS Z8801-1: 2006), the percentage of particles remaining on the 500 μm standard sieve is 30% by weight or less, and the 180 μm standard sieve It is desirable that the proportion of particles remaining on the top is 60% by weight or more.

Materials for the superabsorbent polymer particles may be used without any particular limitation, but those having a water absorption of 40 g/g or more are suitable. Superabsorbent polymer particles include starch-based, cellulose-based, and synthetic polymer-based particles. and acrylic acid (salt) polymers can be used. As for the shape of the superabsorbent polymer particles, the powder particles that are commonly used are suitable, but other shapes can also be used.

As the superabsorbent polymer particles, those having a water absorption rate of 70 seconds or less, particularly 40 seconds or less are preferably used. If the water absorption rate is too slow, the liquid supplied into the absorbent body 56 tends to return to the outside of the absorbent body 56, which is called reversion.

As the superabsorbent polymer particles, those having a gel strength of 1000 Pa or more are preferably used. As a result, even when the absorbent body 56 is bulky, it is possible to effectively suppress the feeling of stickiness after liquid absorption.

The basis weight of the superabsorbent polymer particles can be appropriately determined according to the absorption amount required for the use of the absorbent body 56 . Therefore, although it cannot be generalized, it can be 50 to 350 g/m ² . If the basis weight of the polymer is less than 50 g/m ² , it becomes difficult to secure the absorption capacity. If the amount exceeds 350 g/m ² , not only the effect is saturated, but also the excessive superabsorbent polymer particles give a gritty feeling of discomfort.

(packaging sheet)
In order to prevent the superabsorbent polymer particles from slipping out or to improve the shape retention of the absorbent body 56, the absorbent body 56 can be incorporated as an absorbent element 50 wrapped with a wrapping sheet 58. FIG. As the wrapping sheet 58, tissue paper, especially crepe paper, nonwoven fabric, poly-laminated nonwoven fabric, a sheet with small holes, or the like can be used. However, it is desirable that the sheet is such that the superabsorbent polymer particles do not escape. When non-woven fabric is used instead of crepe paper, hydrophilic SMMS (spunbond/meltblown/meltblown/spunbond) nonwoven fabric is particularly suitable, and polypropylene, polyethylene/polypropylene, etc. can be used as the material.

As shown in FIG. 3, the packaging sheet 58 may have a structure that wraps the entire absorber 56 with one sheet, or may wrap the entire absorber 56 with a plurality of sheets, such as two upper and lower sheets. The packaging sheet 58 can also be omitted.

The basis weight of the packaging sheet 58 is preferably 16 g/m ² or more, more preferably 20 g/m ² or more. By making the packaging sheet 58 thick, it is possible to prevent excrement and acid retained by the absorbent body 56 from returning and adhering to the wearer's skin, thereby imposing a burden on the skin.

(top sheet)
The top sheet 30 is liquid-permeable, and may be, for example, a perforated or non-perforated nonwoven fabric, a porous plastic sheet, or the like. In addition, among these, the nonwoven fabric is not particularly limited as to what the raw material fibers are. Examples include synthetic fibers such as olefins such as polyethylene and polypropylene, polyesters and polyamides, regenerated fibers such as rayon and cupra, and mixed fibers and composite fibers in which two or more of these are used. can. Furthermore, the nonwoven fabric may be manufactured by any processing. Examples of processing methods include known methods such as spunlace, spunbond, thermal bond, meltblown, needle punch, air through, and point bond methods. For example, if flexibility and drapeability are desired, the spunlace method is preferable, and if bulkiness and softness are desired, the thermal bond method is the preferable processing method.

The top sheet 30 extends from the front end to the rear end of the product in the front-rear direction, and extends laterally from the absorbent body 56 in the width direction WD. If necessary, such as when the top sheet 30 is located on the center side in the width direction, the width of the top sheet 30 may be made shorter than the total width of the absorbent body 56, and other suitable modifications may be made.

The top sheet 30 is preferably provided with through-holes 78 penetrating from the skin side surface of the top sheet 30 to the back side surface. In the following description, the through holes 78 provided in the top sheet 30 are referred to as top holes 78 . By providing the top hole 78 , the excreted liquid excreted on the top sheet 30 can be quickly transferred to the intermediate sheet 40 .

As will be described later, the intermediate sheet 40 has a plurality of protrusions 99 projecting from the back side toward the skin side, and recesses 88 formed between the adjacent protrusions 99, 99. The recesses 88 An intermediate hole 77 is formed through the intermediate sheet 40 in the thickness direction. In the following description, the through holes 77 provided in the intermediate sheet 40 are referred to as intermediate holes 77 . The convex portions 99 of the top sheet 30 and the intermediate sheet 40 are connected by a hot-melt adhesive H or the like.

The excreted liquid excreted on the top sheet 30 mainly passes through the contact portion between the top sheet 30 and the convex portion 99 of the intermediate sheet 40 (in the example of FIG. 7, the portion where the hot melt adhesive H is applied), flow to sheet 40; Therefore, in the portion of the top sheet 30 that is not in contact with the intermediate sheet 40 , it is difficult for the excreted liquid to move to the intermediate sheet 40 , and the excreted liquid may be retained inside the top sheet 30 , or the top sheet 30 may be removed. There is a possibility that excretions may be retained on the surface of the skin side. Therefore, by forming the top holes 78 in the portion of the top sheet 30 that is not in contact with the intermediate sheet 40, the top sheet 30 can be prevented from retaining excreted fluid, and the surface of the top sheet 30 on the skin side can be prevented. It is possible to prevent excretions from accumulating on the surface of the body.

Moreover, in the intermediate sheet 40 , the excreted fluid tends to accumulate in the concave portion 88 . When the wearer excretes a large amount of bodily fluids, there is a possibility that a large amount of bodily fluids will temporarily accumulate in the recesses 88 of the intermediate sheet 40 and contact the top sheet 30 . The portion of the top sheet 30 that may come into contact with the intermediate sheet 40 is the portion that overlaps with the recessed portion 88 of the intermediate sheet 40 in a plan view. Therefore, by providing the top hole 78 in the top sheet 30 at a position that overlaps the recessed portion 88 of the intermediate sheet 40, the movement of the excreted liquid from the top sheet 30 to the intermediate sheet 40 is promoted, and the excreted liquid comes into contact with the top sheet 30. This prevents excretions from being retained in the fibers of the top sheet 30 as they are.

FIG. 9 is a sectional view showing the relationship between the top hole 78 provided in the top sheet 30 and the recess 88 of the intermediate sheet 40. As shown in FIG. In the example of FIG. 9, the positions of the top hole 78 and the intermediate hole 77 are aligned in plan view. By aligning the positions of these two through holes 77 and 78, there is an advantage that excreted liquid excreted on the top sheet 30 can be quickly transferred to the absorbent element 50 through these through holes 77 and 78. . However, the present invention is not limited to such a mode, and a mode in which a portion of the top hole 78 and a portion of the intermediate hole 77 overlap in plan view may be employed. Alternatively, the top hole 78 may overlap the portion of the recess 88 where the intermediate hole 77 does not exist, instead of overlapping the top hole 78 and the intermediate hole 77 in plan view.

Another advantage of providing the top hole 78 is that the area of contact between the top sheet 30 and the wearer's skin is reduced, so that air permeability is improved and the wearer's wearing comfort is improved.

It is preferable to provide a plurality of top holes 78 from the viewpoint of increasing the permeability of the top sheet 30 to excreted liquid and from the viewpoint of reducing the contact area between the top sheet 30 and the wearer's skin. From the same two viewpoints, it is preferable that the area of one top hole 78 is large. If the number of top holes 78 is increased or the area of each top hole 78 is increased, there is an advantage that excreted liquid can be quickly delivered to the absorbent element. If the number of top holes 78 is too large or the area of one top hole 78 is too large, there is a problem that the intermediate sheet 40 or the absorbent element 50 is likely to return. Therefore, considering such merits and demerits, the number of top holes 78 is preferably 2 to 100, more preferably 8 to 64, per 100 mm ² of the top sheet 30 . The average area per top hole 78 is preferably 0.3 mm ² to 15 mm ² , more preferably 1.5 mm ² to 8 mm ² . Therefore, the average total area of the plurality of top holes 78 provided in the range of 100 mm ² on the surface of the top sheet 30 is preferably 0.6 mm ² to 1500 mm ² , more preferably 12 mm ² to 512 mm ² . is more preferable.

The top hole 78 of the top sheet 30 can be provided by, for example, the following method.
The nonwoven fabric of the top sheet 30 is passed between the heated convex roll and concave roll, and the top holes 78 are provided. The temperature of the rolls is preferably 100 to 110° C. for the convex roll and 110 to 120° C. for the concave roll.

As described above, the nonwoven fabric forming the topsheet 30 is often made of synthetic fibers. Therefore, they often have hydrophobic properties, except when they are made of natural materials such as cotton. When the non-woven fabric of the top sheet 30 is hydrophobic, the top sheet 30 repels excrement, waterdrop-like masses are formed on the skin-side surface of the top sheet 30, and the excrement permeates from the top sheet 30 to the intermediate sheet 40. do not. Therefore, when the top sheet 30 has hydrophobic properties, it is preferable that the fibers of the top sheet 30 contain a hydrophilic agent. For the same reason, it is preferred that not only the top sheet 30 but also one of the intermediate sheet 40 and the packaging sheet 58 or both the intermediate sheet 40 and the packaging sheet 58 contain a hydrophilic agent.

Preferably, the hydrophilizing agent included in the topsheet 30 is such that a portion of it runs down to the absorbent element 50 when urinating. As the hydrophilic agent runs off, the properties of the topsheet 30 transition from hydrophilic to hydrophobic. If the top sheet 30 is hydrophilic, excretory liquid is likely to accumulate inside the top sheet 30, and there is a possibility of reversion. can be reduced. In addition, if the top sheet 30 is too hydrophobic, there is a problem that excreted liquid does not permeate the top sheet 30 when excreted repeatedly. Therefore, it is preferable to allow the hydrophilic agent to remain on the top sheet 30 to the extent that such problems do not occur.

As a method for producing the top sheet 30 containing the hydrophilic agent as described above, for example, it may be fixed to the top sheet 30 by a method of in-line spray coating during diaper production using a diaper processing machine. In addition, in the process of manufacturing the top sheet 30, other methods such as applying a hydrophilic agent between the stretching and drying processes may be used. It should be noted that if the hydrophilic agent is applied to the fibers constituting the top sheet 30, the hydrophilic agent is less likely to run off from the fibers, which is not so desirable.

The top sheet 30 manufactured as described above is in a state in which the hydrophilic agent is attached to the outer surface of the fibers constituting the top sheet 30 . At the same time, the gaps between the plurality of fibers forming the top sheet 30 may be filled with a hydrophilic agent. Furthermore, in order to prevent the top sheet 30 from being largely hydrophobic, if a portion of the hydrophilic agent is allowed to permeate the interior of the fibers that make up the top sheet 30, the hydrophilic agent will be completely absorbed even after multiple excretions. It is suitable because it becomes difficult to flow down.

In addition, the hydrophilic agent used for the above applications can be used without any particular limitation, and typical examples thereof include various surfactants (anionic, cationic, amphoteric and nonionic). Specifically, for example, polyglycerin fatty acid ester, polyether-polyester block copolymer, polyether-modified silicone, fatty acid ester of ethylene oxide-added polyhydric alcohol, and the like can be used.

The following artificial urine drip test was performed on the top sheet 30 containing a hydrophilic agent, and the first measurement result was 10 points or less, the second measurement result was 5 points or less, and the third measurement result. It is preferable to mount the top sheet 30 having a score of 5 or more on the absorbent article.
[Drip test method for artificial urine]
(1) A top sheet 30 containing a hydrophilic agent is placed on ten sheets of filter paper, and a metal jig 70 having ten holes is placed on the top sheet 30 . In addition, since this test is to confirm whether or not the hydrophilic agent contained in the top sheet 30 is difficult to run off when repeatedly excreted, the top sheet 30 used in this test was need not be included.
(2) (First measurement)
Using a micropipette, 1 mL of artificial urine (to which the colorant described below is added) is dropped into each hole (ie, a total of 10 mL of artificial urine is dropped into 10 holes). After dripping the artificial urine, confirm whether the nonwoven fabric has absorbed the artificial urine within 2 seconds. When the artificial urine remains on the nonwoven fabric (usually when the artificial urine is spherically placed on the nonwoven fabric), it is recorded that the nonwoven fabric does not absorb the artificial urine. On the other hand, when no artificial urine remains on the nonwoven fabric, it is recorded that the nonwoven fabric has absorbed the artificial urine. Do this recording operation for each of the 10 holes. That is, the number of places out of 10 that passed through the nonwoven fabric within 2 seconds is recorded. An absorbed hole is counted as 1 point, and an unabsorbed hole is counted as 0 point, and the total score of 10 holes is recorded.
(3) (Second measurement)
After dropping the artificial urine (with the following colorant added) in (2), wait for 3 minutes to pass, and after 3 minutes, again using a micropipette, each hole Instill 1 mL of artificial urine. Then, the total score is recorded in the same manner as in (2) above.
(4) (Third measurement)
After dropping the artificial urine (with the following colorant added) in (3) above, wait for 3 minutes, and after 6 minutes, use a glass pipette to add 500 μL per hole. Dripping artificial urine. Then, the total score is recorded in the same manner as in (2) above.
(5) In the recording results of (2) to (4) above, the first measurement result is 10 points or less, the second measurement result is 5 points or less, and the third measurement result is 5 points or less. It is preferable to mount the top sheet 30 thus formed on an absorbent article. This is because it can be determined that the hydrophilic agent is likely to run off when urination occurs multiple times.
(filter paper)
As the filter paper used in the test, FILTER PAPER 250 mm×250 mm square manufactured by ADVENTEC is used.
(metal jig)
As the metal jig 70, the following is used.
It has a rectangular shape with a width of 210 mm, a length of 50 mm and a thickness of 5 mm. Ten holes 71 with a diameter of 15 mm are provided at regular intervals of 4 mm in the width and length directions. Weight is 400g.
(artificial urine)
As the artificial urine used in the test, the following are used.
A mixture of urea: 2 wt%, sodium chloride: 0.8 wt%, calcium chloride dihydrate: 0.03 wt%, magnesium sulfate heptahydrate: 0.08 wt%, and deionized water: 97.09 wt% (coloring agent)
Approximately 5 g of Kiriya Food Blue No. 1 (Brilliant Blue FCF) (packaging: powder) is dissolved in approximately 300 ml of the above artificial urine to prepare a solution.
(pipette)
Biohit Proline Pipette 100 to 1000 μl (model number: 720050), for example, can be used as a micropipette used in the artificial urine drop test. As the glass pipette used for the artificial urine dropping test, for example, Maruem KOMA5 5 ml (model number: 0801-04) can be used.

By providing the top hole 78 in the top sheet 30 as described above, the following effects can be obtained. That is, the top sheet 30 can quickly allow the excreted liquid to pass from the front surface (skin side surface) to the back surface. If the permeability of the top sheet 30 is poor, excreted fluids accumulate on the surface (surface facing the skin) of the top sheet 30, and the amount of time that the excreted fluids are in contact with the wearer's skin increases, causing discomfort to the wearer. easy to feel. In the present invention, by providing the top hole 78 and increasing the permeability, it is possible to reduce the amount of time that excrement contacts the wearer's skin, thereby reducing the wearer's discomfort.

In addition, when excrement accumulates on the surface of the top sheet 30 for a long period of time, excrement spreads over a wide area of the top sheet 30 due to the action of the wearer and the penetrating action of the fibers that make up the top sheet 30 (diffusion). do). As a result, the surface area of the excrement remaining on the top sheet 30 becomes large after permeation of the excrement, and the excrement remaining over a wide area comes into contact with the skin, which easily places a burden on the wearer's skin. According to the present invention, since the top sheet 30 is provided with the top holes 78 to increase permeability, the surface area of the excrement remaining on the top sheet 30 is reduced, and the area where the excrement contacts the wearer's skin can be reduced. can. As a result, the burden on the wearer's skin is reduced.

The basis weight of the top sheet 30 is preferably 10-18 g/m ² , more preferably 13-15 g/m ² . In addition, the thickness of the top sheet 30 is preferably 0.1 to 0.3 mm, more preferably 0.2 to 0.3 mm. In addition, the fineness of the fibers constituting the top sheet 30 is preferably 1.8 to 3.0 dtex, more preferably 2.0 to 2.5 dtex.

When the basis weight of the top sheet 30 is greater than 18 g/m ² , the thickness of the top sheet 30 is greater than 0.3 mm, and the fineness of the fibers constituting the top sheet 30 is greater than 3.0 dtex, the top sheet 30 is There is a problem that the top sheet 30 loses its smoothness because it easily retains excrement. Therefore, by setting the basis weight of the top sheet 30 to 18 g/m ² or less, the thickness of the top sheet 30 to 0.3 mm or less, and the fineness of the fibers constituting the top sheet 30 to 3.0 dtex or less, the above problem can be solved. That is, it is possible to solve the problem that the top sheet 30 becomes wet (not dry) and the wearer feels uncomfortable.

On the other hand, when the basis weight of the top sheet 30 is less than 10 g/m ² or when the thickness of the top sheet 30 is less than 0.1 mm, the material strength of the top sheet 30 is weakened, and the top sheet 30 may be torn during use. There is another problem that the uneven texture makes it easier for excrement to return to the skin side.

Further, when the fineness of the fibers constituting the top sheet 30 is thinner than 1.8 dtex, there is another problem that the excreted liquid is difficult to permeate from the top sheet 30 to the back side.

Therefore, by setting the basis weight of the top sheet 30 to 10 g/m ² or more, the thickness of the top sheet 30 to 0.1 mm or more, and the fineness of the fibers constituting the top sheet 30 to 1.8 dtex or more, each of the above-mentioned You can also solve problems.

In the above, preferable values are shown for each of the basis weight, fineness, and thickness of the material itself of the top sheet 30 . If all of the basis weight, fineness, and the thickness of the material itself are set to preferable values, it is preferable because each of the above-mentioned effects appears remarkably, but at least one of the basis weight, the fineness, and the thickness of the material itself is preferable. value to achieve any desired effect.

(intermediate sheet)
An intermediate sheet (also called a “second sheet”) 40 having a faster liquid permeation rate than the top sheet 30 can be provided in order to quickly transfer the liquid that has permeated the top sheet 30 to the absorbent body 56 . The intermediate sheet 40 is intended to quickly transfer the liquid to the absorbent body 56 to enhance the absorption performance of the absorbent body 56 and prevent the "return" phenomenon of the absorbed liquid from the absorbent body 56 .

Examples of the intermediate sheet 40 include materials similar to those of the top sheet 30, spunlace nonwoven fabric, spunbond nonwoven fabric, SMS nonwoven fabric, pulp nonwoven fabric, mixed sheet of pulp and rayon, pointbond nonwoven fabric, and crepe paper. A spunbonded nonwoven fabric is particularly preferred because it is less bulky.

The intermediate sheet 40 in the illustrated example is shorter than the width of the absorbent body 56 and arranged in the center, but it may be provided over the entire width. Further, the intermediate sheet 40 may be provided over the entire length of the diaper, or may be provided only in the intermediate portion including the excretion position as shown in the illustrated example.

The basis weight of the intermediate sheet 40 can be arbitrarily determined, but is preferably 15 to 30 g/m ² , more preferably 20 to 28 g/m ² . Since the basis weight of the general intermediate sheet 40 is 25 to 45 g/m ² , the preferred basis weight is relatively low. When the basis weight of the intermediate sheet 40 is low, the amount of excreted liquid retained in the intermediate sheet 40 is reduced. Therefore, the intermediate sheet 40 is less likely to hold liquid (hold the excreted fluid) than when a general intermediate sheet 40 is used. There is an advantage that the amount of reversion is smaller than that of the general intermediate sheet 40 . When the basis weight of the intermediate sheet 40 is less than 15 g/m ² , the distance between the top sheet 30 and the absorbent body 56 is short, so that the excreted liquid in the absorbent body 56 tends to return to the wearer's skin. There is a problem. On the other hand, when the basis weight of the intermediate sheet 40 is more than 30 g/m ² , the intermediate sheet 40 tends to retain the excreted liquid, and when the excreted liquid in the intermediate sheet 40 is reversed, the amount of the excreted liquid is increased. There is

Although the fineness of the intermediate sheet 40 can be determined arbitrarily, it is preferably 2 to 4 dtex, more preferably 2 to 3 dtex. The thickness of the material itself of the intermediate sheet 40 (thickness before unevenness is provided on the intermediate sheet 40; hereinafter the same) can be determined arbitrarily, but is preferably 0.1 to 1 mm, more preferably 0.3 to 0.6 mm. is more preferable. Although the density of the intermediate sheet 40 can be determined arbitrarily, it is preferably 15,000 to 300,000 g/m ³ , more preferably 20,000 to 280,000 g/m ³ .

If the fineness of the intermediate sheet 40 is less than 2 dtex, the thickness of the material itself is less than 0.1 mm, and the density is less than 15000 g/cm ³ , there is a problem that the amount of excreted liquid retained between the fibers increases. . If the fineness of the intermediate sheet 40 is greater than 4 dtex, the thickness of the material itself is greater than 1 mm, and the density is greater than 300,000 g/m ³ , there is a problem that excreted fluid is difficult to permeate.

As described above, when the body pressure of the wearer is applied to the absorbent article, the excreted liquid held by the intermediate sheet 40 and the excreted liquid held by the absorbent body 56 move to the surface of the top sheet 30 on the skin side. A phenomenon, a so-called reversion phenomenon, may occur. Focusing on the intermediate sheet 40, at least one of the basis weight, fineness, thickness and density of the material itself of the intermediate sheet 40 is set to a preferable value (if all of them are set to preferable values, the effect becomes higher). , the amount of excrement held inside the intermediate sheet 40 may be reduced. This is because if the amount of excreted liquid in the intermediate sheet 40 is reduced, even if the excreted liquid inside the intermediate sheet 40 were to return, the amount of the excreted liquid that would return would be smaller than that of the general intermediate sheet 40, which is advantageous. be.

However, when focusing on the absorber 56, if the basis weight, fineness, thickness and density of the material itself of the intermediate sheet 40 are set to the above-mentioned preferable values, there is a possibility that reversal may rather easily occur. For example, when the thickness of the material itself of the intermediate sheet 40 is reduced, the distance between the top sheet 30 and the absorbent element 50 (and thus the absorbent body 56) is shortened. Therefore, when body pressure is applied to the absorbent article, the excreted liquid held by the absorbent body 56 is likely to return to the top sheet 30 as compared with the case where the material itself of the intermediate sheet 40 is thick. put away.

Therefore, in the present invention, the intermediate sheet 40 is preferably a sheet having a plurality of protrusions 99 projecting from the back side toward the skin side and recesses 88 formed between the adjacent protrusions 99 . By providing the intermediate sheet 40 with the protrusions 99 and the recesses 88, the distance in the thickness direction between the top sheet 30 and the absorbent element 50 (and thus the absorbent body 56) can be increased. As a result, compared to the case where the intermediate sheet 40 is not provided with the protrusions 99 and the recesses 88, the possibility that the excreted liquid held by the absorbent body 56 may return to the top sheet 30 can be reduced.

The shape of the protrusion 99 is not particularly limited. 6 to 10 exemplify the dome-shaped convex portion 99 that draws a circle in plan view, but a dome shape that draws an ellipse or polygon (triangle, quadrilateral, or other polygon) in plan view is used. Also good. The shape protruding toward the skin side is not limited to a dome shape, and may be any shape such as a cylindrical shape.

The diameter of the projection 99 in plan view is preferably 0.5 to 5 mm, more preferably 2 to 3 mm. If the diameter of the projections 99 is less than 0.5 mm, the projections 99 will be too sharp, and the top sheet 30 and the intermediate sheet 40 will not be fixed well. Conversely, if the diameter of the protrusion 99 is longer than 5 mm, the protrusion 99 as a whole becomes too large, making it difficult to maintain the shape of the protrusion 99 when body pressure or the like is applied. In addition, when the shape of the convex portion 99 is not circular in plan view, for example, when it is an ellipse, or when it is a polygonal shape such as a quadrangle, the projected circle equivalent diameter (diameter of a circle equal to the projected area of the convex portion 99) is used. Say. The diameter of the projections 99 is the average value of the diameters of all the projections 99 provided within an arbitrary area (100 mm×100 mm square) of the intermediate sheet 40 . In addition, it is preferable to select a portion that abuts on the wearer's excretory opening as the arbitrary portion of the intermediate sheet.
The above points also apply to the through holes 77 and 78 . When the through-holes 77 and 78 have different diameters in the thickness direction, it means the projected circle equivalent diameter of the smallest portion. This is because the through-holes 77 and 78 are required to permeate the liquid, and the minimum portion is rate-determining.

The distance between the plurality of protrusions 99 can be arbitrarily determined. For example, in the embodiment of FIG. 7, the distance L1 between the apexes h1, h1 of the adjacent projections 99, 99 is preferably 2-10 mm, more preferably 3-5 mm. If the distance L1 is shorter than 2 mm, there is a problem that the processing suitability for opening an intermediate hole 77, which will be described later, is lowered. Conversely, when the distance L1 is longer than 10 mm, there is a problem that the convex portion 99 is easily crushed.

7, when two or more intermediate holes 77 are provided between the adjacent protrusions 99, 99, the distance L2 between the adjacent intermediate holes 77, 77 (intermediate hole 77 to the center of the adjacent intermediate hole 77) is preferably 1 to 5 mm, more preferably 2 to 4 mm. If the distance L2 is shorter than 1 mm, there is a problem that the processing suitability for opening the intermediate hole 77 is low, or the peripheral edge portion having high density and rigidity is almost continuous, so that the wearer feels hardness. There is a problem. Conversely, when the distance L2 is longer than 5 mm, there is a problem that the convex portion is easily crushed.

7, when two or more intermediate holes 77 are provided between the adjacent protrusions 99, 99, the recesses 88 sandwiched between the adjacent intermediate holes 77, 77 The distance L3 is preferably 0.5 to 4 mm, more preferably 0.5 to 3 mm. If the distance L3 is shorter than 0.5 mm, there is a problem that the processing suitability for opening the intermediate hole 77 is low, or the peripheral edge portion with high density and rigidity is almost continuous, so that the wearer does not feel the hardness. I have a problem with feeling it. Conversely, if the distance L3 is longer than 4 mm, there is a problem that the convex portion 99 is easily crushed.

7 and 9, when the intermediate hole 77 is provided between the adjacent protrusions 99, 99, the distance L4 from the edge of the protrusion 99 to the edge of the intermediate hole 77 is 0 to 2 mm is preferable, and 0 to 1 mm is more preferable. If the distance L4 is shorter than 2 mm, there is a problem that the convex portion 99 is easily crushed.

Also, the height h of the projections 99 of the intermediate sheet 40 is preferably 1 to 2 mm, more preferably 1 to 1.5 mm. Here, as shown in FIG. 7, the height h of the protrusions 99 means the vertex h1 of the protrusions 99 on the skin-side surface of the intermediate sheet 40 and the vertical line drawn from the vertex h1, The distance between the point h2 at which the bottom surface h3 of the recess 88 intersects at the same height on the surface of the . If the height of the protrusions 99 is less than 1 mm, the distance in the thickness direction between the top sheet 30 and the absorbent element 50 is not sufficient, and the excreted liquid retained by the absorbent element 50 tends to return to the top sheet 30. There's a problem. If the height of the protrusions 99 is higher than 2 mm, there is a problem that the shape of the protrusions 99 tends to collapse when body pressure or the like is applied to the intermediate sheet 40 .

As described above, by providing the intermediate sheet 40 with the convex portion 99 and the concave portion 88, the space 98 is formed between the top sheet 30 and the intermediate sheet 40, and the intermediate sheet 40 and the packaging sheet 58 of the absorbent element 50 are separated from each other. A space 97 is formed between. By forming these spaces, it is possible to prevent reversion from the absorbent element 50 to the top sheet 30 .

If the intermediate sheet 40 is provided with the protrusions 99 and the recesses 88 , the excreted liquid reaching the intermediate sheet 40 from the top sheet 30 may pool in the recesses 88 . More specifically, the space 98 between the topsheet 30 and the middle sheet 40 can pool. Therefore, by forming an intermediate hole 77 (hereinafter referred to as an intermediate hole 77) penetrating in the thickness direction in the concave portion 88 of the intermediate sheet 40, the occurrence of liquid puddles during excretion is suppressed, and the excreted liquid is quickly absorbed by the absorbent element. Allows you to reach 50.

From the viewpoint of increasing the permeability of the intermediate sheet 40 to excreted fluid, it is preferable to provide a plurality of intermediate holes 77 . From the same point of view, it is preferable that the area of one intermediate hole 77 is large. If the number of intermediate holes 77 is increased or the area of each intermediate hole 77 is increased, there is an advantage that excreted liquid can be quickly delivered to the absorbent element. If the number of intermediate holes 77 is too large or if the area of one intermediate hole 77 is too large, there is a problem that backflow from the absorbent element 50 is likely to occur. Therefore, considering such merits and demerits, the number of intermediate holes 77 is preferably 1 to 25, more preferably 4 to 16 per 100 mm ² of the intermediate sheet 40 . The average area of each intermediate hole 77 is preferably 0.3 mm ² to 1.0 mm ² , more preferably 0.4 mm ² to 0.5 mm ² . Therefore, the total area of the plurality of intermediate holes 77 provided in the range of 100 mm ² on the surface of the intermediate holes 77 is preferably 0.3 mm ² to 25 mm ² on average, and 1.6 mm ² to 8 mm ² . is more preferable.

The intermediate hole 77 of the intermediate sheet 40 can be provided by, for example, the following method.
The non-woven fabric of the intermediate sheet 40 is passed between the heated convex roll and concave roll, and intermediate holes 77 are provided. The temperature of the rolls is preferably 100 to 110° C. for the convex roll and 110 to 120° C. for the concave roll. It is preferable to provide the intermediate sheet 40 with the protrusions 99 and the recesses 88 by a similar method. The protrusion 99 and the recess 88 and the intermediate hole 77 may be provided at different timings, but the simultaneous provision can shorten the manufacturing time. That is, after the non-woven fabric of the intermediate sheet 40 is passed between the heated convex roll and the concave roll to form the convex portions 99 and the concave portions 88, the intermediate sheet 40 having the concave and convex portions is placed between the heated convex roll and the concave roll. Although it is possible to form the intermediate hole 77 by passing it between the rolls, the production time is lengthened and the number of convex rolls and concave rolls is increased, which increases the cost of the production equipment. Therefore, the nonwoven fabric of the intermediate sheet 40 is passed between a set of heated convex rolls and concave rolls to simultaneously form the convex portions 99, the concave portions 88, and the intermediate holes 77, thereby shortening the manufacturing time and reducing the manufacturing equipment cost. It is preferable to aim for

It is preferable that the peripheral edge portion 77R of the intermediate hole 77 provided in the recessed portion 88 of the intermediate sheet 40 has a higher fiber density than the portion 77N of the recessed portion 88 of the intermediate sheet 40 that is not the peripheral edge portion 77R. This is because when body pressure or the like is applied to the intermediate sheet 40 , the high fiber density of the peripheral edge portion 77</b>R of the intermediate hole 77 increases the rigidity around the convex portion 99 and prevents the shape of the convex portion 99 from collapsing. be. If the peripheral edge portion 77R of the intermediate hole 77 does not have a high fiber density, body pressure tends to cause the protrusion 99 to lose its shape. Since 77R resists the body pressure, the shape of the projection 99 can be maintained as a result. In addition, FIG. 6 shows a peripheral edge portion 77R of the intermediate hole 77 and a region other than the peripheral edge portion 77R. The hardened peripheral edge portion 77R is formed at a distance of 0.01 to 0.1 mm from the edge of the intermediate hole 77 in the radial direction. It is preferable that the height of the fiber density of the hardened peripheral portion 77R is, for example, about 1.5 to 3.0.

In order to make the fiber density of the peripheral edge portion 77R of the intermediate hole 77 higher than that of the portion 77N other than the peripheral edge portion 77R, for example, when forming the intermediate hole 77, the convex steel material of the convex roll is inserted into the intermediate sheet 40. do it. By forming the intermediate hole 77 in this way, as shown in FIG. 12, a protruding portion (burr) 14e is formed around the intermediate hole 77 and hardened.

The cross-sectional shape of the intermediate hole 77 is not particularly limited. For example, even if the intermediate hole 77 is a punched-type hole whose periphery is formed by cut ends of fibers as shown in FIG. 12(d), as shown in FIGS. The intermediate hole 77 may be a pin-insertion type intermediate hole 77 (having a high density of fibers at the edge) formed by inserting a pin between the fibers and expanding the fiber with almost no cut ends of fibers around the periphery of the intermediate hole 77 . . As shown in FIG. 12(d), the punched-type hole may be one in which the diameter of the intermediate hole 77 becomes smaller toward the middle in the thickness direction, or one in which the diameter becomes smaller toward one side in the thickness direction. good. The diameter of the intermediate hole 77 means the dimension in the direction passing through the center of gravity of the hole and perpendicular to the expansion/contraction direction (therefore, in the case of a circle, it is the diameter, and in the case of an ellipse, it is the major axis). Furthermore, as the diameter of the intermediate holes 77 decreases in the thickness direction, in addition to the fact that the diameter of the intermediate holes 77 continues to decrease throughout the thickness direction of the nonwoven fabric layer, the diameter of the intermediate holes 77 decreases in the middle of the thickness direction. Including those that are almost non-existent.

The pin insertion type intermediate hole 77 has a diameter that decreases from the pin insertion side toward the opposite side. In such a pin-insertion type hole, as shown in FIGS. 12(a) and 12(c), fibers are extruded to the edge of the intermediate hole 77 on the side opposite to the pin insertion side. A projecting portion ( burr ) 14e is formed and the projecting portion 14e is not formed on the pin insertion side, and as shown in FIG. A projecting portion 14e extruded to the side opposite to the pin insertion side is formed, and a projecting portion 14e lower than this is formed on the pin insertion side. Furthermore, in the former type of hole 14, as shown in FIG. It includes a facing portion having the highest height and a facing portion facing in a direction orthogonal thereto and having the lowest protrusion height. It is desirable that the projecting portion 14e is continuous in the circumferential direction of the hole and has a tubular shape, but the projecting portion 14e of some or all of the intermediate holes 77 is formed only partially in the circumferential direction of the intermediate hole 77. may be The height of the projection (apparent height measured with an optical microscope when no pressure is applied) is preferably about 0.2 to 1.2 mm. Incidentally, due to the formation of the protruding portion 14e, the protruding portion 14e may be formed on the skin side as shown in FIG. 12(b). It is different from the convex portion 99 . In addition, when measuring the height h of the projection 99, the measurement is performed assuming that the projection 14e is not present.

The locations where the projections 99, the recesses 88, and the intermediate holes 77 are formed on the intermediate sheet 40 are not particularly limited. In the embodiment of FIG. 6, six intermediate holes 77 are provided around one convex portion 99, and in the embodiment of FIG. 8, four intermediate holes 77 are provided around one convex portion 99. 10, eight intermediate holes 77 are provided around one convex portion 99. As shown in FIG. When the peripheral edge portion 77R of each intermediate hole 77 is hardened, there is an advantage that the rigidity increases as the number of the intermediate holes 77 increases, and the shape of the convex portion 99 is less likely to collapse. Conversely, if the peripheral edge portion 77R of each intermediate hole 77 is not hardened, there is a disadvantage that the rigidity becomes weaker as the number of intermediate holes 77 increases, and the shape of the convex portion 99 tends to collapse. The number of intermediate holes 77 may be arbitrarily determined depending on whether the peripheral edge portion 77R of the intermediate hole 77 is hardened and how much the shape of the convex portion 99 is desired to be maintained. Further, rather than providing a plurality of convex portions 99 in a straight line as in FIGS. 6 and 8, it is better to provide the convex portions 99 in a curved shape as shown in FIG. It has the advantage of not easily falling apart. In FIG. 8, the angle P between the protrusions 99 adjacent to each other in the zigzag direction can be set to 90 degrees. This angle P can be determined arbitrarily, preferably 45 to 120 degrees, more preferably 60 to 100 degrees.

In addition, when the top hole 78 formed in the top sheet 30 and the intermediate hole 77 formed in the intermediate sheet 40 overlap at least partially in a plan view, the excreted fluid excreted in the top sheet 30 is absorbed. Element 50 can be reached quickly.

However, in actual manufacturing of the absorbent article, it is difficult to align the positions of the top hole 78 and the intermediate hole 77 so as to overlap each other in plan view. Therefore, it is preferable to make the diameter of the top hole 78 larger than the diameter of the intermediate hole 77 to facilitate this alignment.

FIG. 14 is a plan view illustrating an aspect in which the diameter of the top hole 78 is longer than the diameter of the intermediate hole 77. FIG. By increasing the diameter of the top hole 78, it becomes easier to form a portion 79 (overlapping portion) in which the top hole 78 and the intermediate hole 77 overlap in plan view. 14(a) shows an aspect in which the intermediate hole 77 completely overlaps the top hole 78, and FIG. 14(b) shows an aspect in which a portion of the intermediate hole 77 overlaps a portion of the top hole 78. FIG.

In addition, in FIG. 14, the diameter of the top hole 78 is three times the diameter of the intermediate hole 77 . The diameter of the top hole 78 is preferably 2 to 4 times longer than the diameter of the intermediate hole 77, more preferably 2.5 to 3.5 times longer.
Further, in FIG. 14, the distances between the center points of the top holes 78, 78 adjacent vertically and horizontally in the drawing are all the same length, but they may be arbitrarily different lengths. Similarly, in FIG. 14, the distances between the center points of the intermediate holes 77, 77 adjacent vertically and horizontally in the drawing are all the same length, but they may be arbitrarily different lengths.

A mode in which the diameter of the intermediate hole 77 is made larger than the diameter of the top hole 78 is also conceivable. However, since the intermediate sheet 40 is provided with the convex portion 99 , there is a restriction on increasing the diameter of the intermediate hole 77 . Therefore, it is preferable to increase the diameter of the top hole 78 .

In order to overlap the top holes 78 formed in the top sheet 30 and the intermediate holes 77 formed in the intermediate sheet 40 in plan view, the number of the top holes 78 is made larger than the number of the intermediate holes 77, and this position is Facilitating alignment is also a preferred aspect.

FIG. 15 is a plan view illustrating an aspect in which the number of top holes 78 is greater than the number of intermediate holes 77. FIG. By increasing the number of top holes 78, it becomes easier to form a portion 79 (overlapping portion) in which the top holes 78 and the intermediate holes 77 overlap each other in plan view. 15(b) shows an aspect in which the intermediate hole 77 completely overlaps the top hole 78, and FIG. 15(b) shows an aspect in which a portion of the intermediate hole 77 overlaps a portion of the top hole 78. FIG.

15, the number of top holes 78 is twice the number of intermediate holes 77. As shown in FIG. The number of top holes 78 is preferably 2 to 4 times the number of intermediate holes 77, more preferably 2.5 to 3.5 times.
Also, in FIG. 15, the distances between the center points of the top holes 78, 78 adjacent vertically and horizontally in the drawing are all the same length, but they may be arbitrarily different lengths. Similarly, in FIG. 15, the distances between the center points of the intermediate holes 77, 77 adjacent vertically and horizontally in the drawing are all the same length, but they may be arbitrarily different lengths.

It is possible to consider a mode in which the number of intermediate holes 77 is greater than the number of top holes 78, but since the intermediate sheet 40 is provided with the protrusions 99, the number of intermediate holes 77 should be increased. There are restrictions on it. Therefore, it is preferable to increase the number of top holes 78 .

In the above description, "in plan view, the top hole 78 formed in the top sheet 30 and the intermediate hole 77 formed in the intermediate sheet 40 at least partially overlap" means that a plurality of top holes are provided. 78 and at least one of the plurality of intermediate holes 77 overlap each other in plan view. Here, "one or more holes overlap in plan view" means that the positions of the top hole 78 and the intermediate hole 77 are completely aligned in plan view, and that the top hole 78 is partially aligned. and part of the intermediate hole 77 overlap in plan view.

(liquid-impermeable sheet)
The liquid-impermeable sheet 11 is not particularly limited, but preferably has moisture permeability. As the liquid-impermeable sheet 11, for example, an inorganic filler is kneaded in an olefin resin such as polyethylene or polypropylene, the sheet is molded, and then the sheet is stretched in a uniaxial or biaxial direction. A sheet can be preferably used. Moreover, as the liquid-impermeable sheet 11, a non-woven fabric as a base material with improved waterproofness can also be used.

It is desirable that the liquid-impermeable sheet 11 extends in the same or wider range than the absorbent body 56 in the front-rear direction LD and the width direction WD. A structure in which the end portions of the absorber 56 are not covered in the front-rear direction LD and the width direction WD may also be employed.

(exterior non-woven fabric)
The exterior nonwoven fabric 12 covers the entire back side of the liquid-impermeable sheet 11 to give the outer surface of the product a cloth-like appearance. The exterior nonwoven fabric 12 is not particularly limited, and examples of raw material fibers include olefin-based, polyester-based, and polyamide-based synthetic fibers such as polyethylene or polypropylene, regenerated fibers such as rayon and cupra, and natural fibers such as cotton. A spunlace method, a spunbond method, a thermal bond method, an air through method, a needle punch method, or the like can be used as a processing method. However, spunbond nonwoven fabrics, SMS nonwoven fabrics, SMMS nonwoven fabrics, and other long-fiber nonwoven fabrics are suitable because they can achieve both good texture and strength. The non-woven fabric can be used singly or in multiple layers. In the latter case, it is preferable to bond the nonwoven fabrics together with a hot-melt adhesive or the like. When non-woven fabric is used, its fiber basis weight is preferably 10 to 50 g/m ² , particularly 15 to 30 g/m ² .

(Getting up gathers)
On both sides of the top sheet 30 in the width direction WD, rise gathers 60 standing up toward the wearer's skin are provided in order to prevent excrement from moving laterally along the top sheet 30 and prevent so-called side leakage. preferably. Of course, the rising gathers 60 can be omitted.

When adopting the rising gathers 60, the structure is not particularly limited, and any known structure can be adopted. The illustrated rising gathers 60 are composed of a gathering sheet 62 substantially continuous in the width direction WD, and an elongated gathering elastic member 63 fixed to the gathering sheet 62 in a stretched state along the front-rear direction LD. ing. As the gather sheet 62, a water-repellent nonwoven fabric can be used, and as the gather elastic member 63, thread rubber or the like can be used. The elastic member may be provided in a plurality of pieces as shown in FIGS. 1 and 2, or may be provided in a single piece.

The inner surface of the gather sheet 62 has a joining start end in the width direction WD on the side of the top sheet 30, and the portion outside the joining end in the width direction is the inner surface of each side flap portion SF, that is, the liquid impermeable in the illustrated example. The nonwoven fabric 12 is bonded to the side of the adhesive sheet 11 and to the side of the exterior nonwoven fabric 12 positioned on the outside in the width direction thereof with a hot-melt adhesive or the like.

Around the legs, the width direction inner side from the joining start end of the rising gathers 60 is fixed on the top sheet 30 at both ends in the front and back direction of the product, but the portion in between is a non-fixed free portion. It rises due to the contractile force of the elastic member 63 and comes to adhere to the surface of the body.

(end flap part, side flap part)
The illustrated tape-type disposable diaper has a pair of end flap portions EF without the absorbent body 56 extending to the front side and the rear side of the absorbent body 56 respectively, It has a pair of side flap portions SF which do not have the absorber 56 and which extend from each other. The side flap portions SF may be made of a material (exterior nonwoven fabric 12 or the like) that continues from the portion having the absorber 56 as shown in the drawing, or may be formed by attaching another material.

(flat gather)
A side elastic member 64 made of an elongated elastic member such as rubber thread is fixed to each side flap portion SF while being stretched along the front-rear direction LD. is constructed as a planar gather. As shown in the figure, the leg elastic members 64 are provided between the gathered sheet 62 and the liquid-impermeable sheet 11 on the outside in the width direction near the joining start end of the joined portion of the gathered sheet 62. It can also be provided between the liquid-impermeable sheet 11 and the exterior nonwoven fabric 12 in the SF. A plurality of leg-surrounding elastic members 64 may be provided on each side as in the illustrated example, or only one leg-surrounding elastic member 64 may be provided on each side.

The planar gathers are portions on which the contractile force of the side elastic members 64 acts (portions where the side elastic members 64 are illustrated in the drawing). Therefore, in addition to the form in which the side elastic members 64 are present only in the planar gathers, the side elastic members 64 are present on the front side, the rear side, or both sides of the planar gathers, but the side elastic members 64 are present in areas other than the planar gathers. If the member is finely cut at one point or multiple points, or is not fixed to the sheet sandwiching the side elastic member 64, or both, the contractile force will not act on the part other than the planar gather. Also included is a structure in which the contractile force of the side elastic members 64 acts only on the plane gathers instead (substantially equivalent to not providing an elastic member).

(connecting tape)
The side flap portions SF of the dorsal portion B are provided with connecting tapes 13 that are detachably connected to the outer surface of the ventral portion F, respectively. When wearing the disposable diaper 10, the connecting tape 13 is wrapped around the outer surface of the abdominal portion F from both sides of the waist, and the connecting portions 13A of the connecting tape 13 are connected to the outer surface of the abdominal portion F at appropriate locations.

Although the structure of the connecting tape 13 is not particularly limited, in the illustrated example, it has a base end portion 13C fixed to the side flap portion SF and an extension portion 13B extending from the base end portion 13C to the outside in the width direction WD. The extension part 13B has a sheet base material and a connection part 13A provided in the widthwise middle part of the sheet base material and connected to the ventral outer surface. ing.

As the connection portion 13A, a hook member (male member) of a mechanical fastener (surface fastener) may be provided, or an adhesive layer may be provided. The hook material has a large number of engaging projections on its connection surface, and the shapes of the engaging projections are (A) square-shaped, (B) J-shaped, (C) mushroom-shaped, and (D). Although there are a T shape, (E) a double J shape (a shape in which two J shapes are joined back to back), and the like, any shape may be used.

Nonwoven fabrics, plastic films, polylaminated nonwoven fabrics, paper, and composite materials thereof can be used as the sheet base material forming the base end portion 13C to the extension portion 13B. A spunbond nonwoven fabric, an air-through nonwoven fabric, or a spunlaced nonwoven fabric having a weight of 20 to 100 g/m ² and a thickness of 1 mm or less is preferred.

(target sheet)
It is preferable to provide a target portion at a connecting portion of the connecting tape 13 in the ventral portion F. As shown in FIG. The target portion can be provided by attaching a target sheet 20 to the outer surface of the ventral portion F for facilitating connection, as shown in the illustrated example. When the connecting portion 13A is a hook material, the target sheet 20 may be one in which a large number of loop threads are provided on the surface of the sheet base material made of a plastic film or nonwoven fabric so that the engaging projections of the hook material can be entangled. Further, in the case of the adhesive layer, a sheet substrate made of a plastic film having a smooth surface and having high adhesiveness and having a release treatment applied to the surface thereof can be used. In addition, when the connecting portion of the connecting tape 13 in the ventral portion F is made of nonwoven fabric, for example, when the outer nonwoven fabric 12 is provided as shown in the figure, the target sheet 20 is omitted and the hook material is used as the fiber of the outer nonwoven fabric 12. It can also be tangled and connected. In this case, a target sheet 20 as a mark may be provided between the outer nonwoven fabric 12 and the liquid-impermeable sheet 11, or a mark may be printed on the outer surface of the outer nonwoven fabric 12 or the liquid-impermeable sheet 11.

(Wing part)
This tape-type disposable diaper has a crotch portion M extending from the midpoint of the ventral portion F in the front-rear direction LD to the midpoint of the back portion B in the front-rear direction LD, as shown in FIGS. In addition, the ventral portion F and the dorsal portion B have wing portions WP that extend outward from the crotch portion M in the width direction WD. The lower edges 70 of the wing portions of the abdominal portion F extend forward from the front ends of the side edges of the crotch portion M so as to be positioned obliquely outward, and the lower edges 75 of the wing portions of the dorsal portion B It extends from the rear end of the side edge of the crotch portion M so as to be positioned obliquely outward toward the rear. Although the side edge of the wing portion WP is linear in the illustrated example, the shape is not limited to this, and other known shapes can be adopted. The dimension of the crotch portion M in the front-rear direction LD can be determined as appropriate, but it can be about 1.2 to 1.4 times the minimum width M _X of the crotch portion M. In the case of use for infants, the dimension M _Y in the front-rear direction LD of the crotch portion M is about 10 to 30 cm.

[Experimental example 1]
(1) Example 1
The test piece 91 of Example 1 is a spunbond nonwoven fabric having a basis weight of 24 g/m ² , and is a sheet provided with a plurality of protrusions 99 and recesses 88 and having intermediate holes 77 in the recesses 88 . The positional relationship between the projections 99, the recesses 88 and the intermediate holes 77 of this sheet is the same as in FIG. In this sheet, the projections 99, the recesses 88, and the intermediate holes 77 are all circular in plan view, the diameter of the projections 99 being 2.25 mm, and the diameter of the intermediate hole 77 being 0.3 mm. The height h of the protrusion 99 is 1.5 mm. The distance L1 between the adjacent projections 99 is 3.9 mm, and two intermediate holes 77 are provided in the recess 88 between the adjacent projections 99,99. The distance L2 between adjacent intermediate holes 77 is 2.25 mm, and the distance L3 between recesses 88 located between adjacent intermediate holes 77 is 1.65 mm.

The experiment was conducted in a laboratory at 25° C., and 50 cc of artificial urine was injected into the test piece 91 as the intermediate sheet 40 using the injection cylinder 90 (first injection). The injection tube 90 is a hollow cylinder with an outer diameter of 25 mm (inner diameter of 23 mm) and a central axis length of 100 mm. The test piece 91 was placed on an acrylic pedestal 92 having a width of 100 mm, a depth of 100 mm, and a thickness of 5 mm. Artificial urine AU contains 2 wt% urea, 0.8 wt% sodium chloride, 0.03 wt% calcium chloride dihydrate, 0.08 wt% magnesium sulfate heptahydrate, and 97.09 wt% deionized water. It is a mixture. In order to apply a load to the pedestal 92 when the artificial urine AU is injected, a weight 93 having a width of 100 mm, a depth of 100 mm, and a hole with a diameter of 25 mm at the center is used to place the weight on the intermediate sheet 40. A load of 2 kg/10 cm ² was applied. This load assumes that the body pressure of the wearer is applied.

The time from the start of injection of the artificial urine AU until the artificial urine AU became invisible on the surface of the sheet 91 was measured, and this was taken as the absorption rate of the first artificial urine AU. After 1800 seconds from the completion of the first injection, the artificial urine AU was injected into the same place as the first injection (second injection). The injection amount of artificial urine AU is the same as the first time. Then, the time from when the injection of the artificial urine AU was started until the artificial urine AU disappeared on the surface of the sheet 91 was measured, and this was taken as the absorption speed of the artificial urine AU for the second time. Further, 1800 seconds after finishing the second injection, the artificial urine AU was injected into the same place as the second injection (third injection). The injection amount of artificial urine AU is the same as the first and second injections. Then, the time from when the injection of the artificial urine AU was started until the artificial urine AU became invisible on the surface of the sheet 91 was measured, and this was taken as the absorption speed of the artificial urine AU for the third time.

A reversal test was performed 1200 seconds after finishing the injection of the third artificial urine AU. Specifically, a weight of 100 mm in width and 100 mm in depth (a weight different from the weight 93, not shown) was used to apply a load of 5 kg to the pedestal 92 for 600 seconds. After stacking the sheets, a load of 5 kg/10 cm ² was applied again for 20 seconds using the same weight. Then, the amount of artificial urine regurgitation was calculated from the difference between the weight of the filter paper before the test and the weight of the filter paper after the test.

(2) Example 2
The same test as in Example 1 was conducted. The test piece 91 of Example 2 is a spunbond nonwoven fabric having a basis weight of 22 g/m ² , and has a plurality of protrusions 99 and recesses 88 , and the recesses 88 have intermediate holes 77 . The positional relationship between the projections 99, the recesses 88 and the intermediate holes 77 of the sheet 91 is the same as in FIG. The convex portion 99, the concave portion 88 and the intermediate hole 77 of the sheet 91 are all circular in plan view, the diameter of the convex portion 99 being 3.24 mm and the diameter of the intermediate hole 77 being 0.5 mm. Also, the height h of the projection 99 is 1.5 mm. A distance L1 between adjacent protrusions 99 is 4.24 mm, and one intermediate hole 77 is provided in the recess 88 between the adjacent protrusions 99,99. Everything is the same as Example 1 except that the distance L2 between adjacent intermediate holes 77 is 4.24 mm.

(3) Comparative Example 1
The same test as in Example 1 was conducted. A test piece 91 of Comparative Example 1 is a spunbond nonwoven fabric having a basis weight of 20 g/m ² and is completely the same as Example 1 except that the convex portions 99 and the concave portions 88 are not formed.

(4) Comparative Example 2
The same test as in Example 1 was conducted. A test piece 91 of Comparative Example 2 is a spunbond nonwoven fabric having a basis weight of 30 g/m ² and is the same as Example 1, except that the projections 99, the recesses 88 and the intermediate holes 77 are not formed.

The test results are shown in Table 1 below.

(Discussion)
In Examples 1 and 2, in which the protrusions 99 and the recesses 88 were provided, the amount of artificial urine AU that returned was smaller than in Comparative Examples 1 and 2, in which they were not provided. In addition, it was found that Example 1, Example 2, and Comparative Example 1, in which the intermediate hole 77 was provided, had a higher rate of absorption of the artificial urine AU than Comparative Example 2, in which the intermediate hole 77 was not provided.

(excretions)
Examples of excretions in the present invention include urine, defecation (particularly loose stool), menstrual blood, and the like.

<Description of terms in the specification>
The following terms in the specification have the following meanings unless otherwise specified in the specification.
・"Front-back direction" means the direction (longitudinal direction) indicated by symbol LD in the figure, and "width direction" means the direction (left-right direction) indicated by WD in the figure. are orthogonal.

- "Curve" means not including a straight line.

- "Unfolded state" means a flat unfolded state without contraction or slack.

- "Elongation rate" means a value when the natural length is taken as 100%. For example, an elongation rate of 200% is synonymous with an elongation ratio of 2 times.

- "Metsuke" is measured as follows. After pre-drying the sample or test piece, it is left in a test room or apparatus under standard conditions (test location: temperature 23±1° C., relative humidity 50±2%) to a constant weight. Pre-drying refers to making a sample or test piece constant weight in an environment at a temperature of 100°C. Fibers with an official moisture content of 0.0% do not need to be pre-dried. Using a sampling template (100 mm x 100 mm), a sample with dimensions of 100 mm x 100 mm is cut from the constant weight specimen. The weight of the sample is measured, multiplied by 100 to calculate the weight per square meter, and used as the basis weight.

- "Thickness" is automatically measured using an automatic thickness gauge (KES-G5 handy compression tester) under the conditions of a load of 0.098 N/cm ² and a pressurized area of 2 cm ² .

・The “water absorption” is measured according to JIS K7223-1996 “Testing method for water absorption of super absorbent polymer”.

・"Water absorption rate" is "Time to end point" when JIS K7224-1996 "Test method for water absorption rate of superabsorbent polymer" is performed using 2g of superabsorbent polymer and 50g of physiological saline. and

・If there is no description about the environmental conditions for testing and measurement, the test and measurement shall be performed in a test room or equipment under standard conditions (test location: temperature 23±1°C, relative humidity 50±2%).

・Unless otherwise specified, the dimensions of each part mean the dimensions in the unfolded state, not in the natural length state.

The present invention can be applied to absorbent articles such as tape-type disposable diapers, pad-type disposable diapers, and napkins, in addition to the tape-type disposable diapers described above. In particular, application to each disposable diaper is suitable.

DESCRIPTION OF SYMBOLS 11... liquid impermeable sheet, 12... exterior nonwoven fabric, 13... connection tape, 13A... connection part, 13B... extension part, 13C... base end part, 20... target sheet, 30... top sheet, 40... intermediate sheet, 50... Absorption element, 56... Absorbent body, 58... Wrapping sheet, 60... Standing gather, 62... Gather sheet, 64... Side elastic member, 70... Metal jig, 71... Hole, 77... Intermediate hole (intermediate sheet through hole), 78 ... top hole (through hole of top sheet), 79 ... overlapping portion (part where top hole and intermediate hole overlap in plan view), 88 ... concave portion, 90 ... injection cylinder, 91 ... test piece (Sheet) 92 Pedestal 93 Weight 97 Space between intermediate sheet and packaging sheet 98 Space between top sheet and intermediate sheet 99 Projection h Between intermediate sheet and packaging sheet thickness, B... Dorsal part, F... Abdominal part, H... Adhesion part, LD... Anterior-posterior direction, M... Crotch part, SF... Side flap part, WD... Width direction, WP... Wing part, AU... Artificial urine

Claims (7)

An absorbent article comprising a top sheet provided on the skin side, an absorbent element provided on the back side of the top sheet, and an intermediate sheet provided between the top sheet and the absorbent element,
The intermediate sheet has a plurality of convex portions protruding from the back side toward the skin side and concave portions formed between the adjacent convex portions,
The convex portions are arranged in a zigzag pattern at intervals,
The recesses are continuous in a hexagonal shape so as to pass between all the adjacent protrusions,
Intermediate holes penetrating through the intermediate sheet in the thickness direction are formed at least at intersections of the recesses in the intermediate sheet, and six or more intermediate holes surround the protrusions around the protrusions. is provided,
The intermediate hole has an area of 0.3 mm ² to 1.0 mm ² ,
the distance from the edge of the protrusion to the edge of the intermediate hole is 0 to 2 mm;
The diameter of the convex portion in plan view is 0.5 mm to 5 mm,
The height of the convex portion is 1 to 2 mm,
The intermediate sheet is made of nonwoven fabric,
In the concave portion of the intermediate sheet, the peripheral portion of the intermediate hole has a higher fiber density than the portion other than the peripheral portion.
An absorbent article characterized by: 2. The absorbent article according to claim 1, wherein said intermediate hole is a pin insertion type through hole formed by inserting a pin between fibers of said intermediate sheet and spreading the fibers. The top sheet has a basis weight of 10 to 18 g/m ² ,
The top sheet has a fineness of 1.8 to 3.0 dtex,
The top sheet has a thickness of 0.1 to 0.3 mm,
3. The absorbent article according to claim 1 or 2. The topsheet contains a hydrophilic agent,
The hydrophilic agent is attached to the outside of the fibers constituting the top sheet,
A part of the hydrophilic agent adhering to the top sheet flows down together with the wearer's excrement,
In the artificial urine dropping test, the top sheet has a first measurement result of 10 points or less, a second measurement result of 5 points or less, and a third measurement result of 5 points or less. The absorbent article according to any one of claims 1-3. The top sheet is formed with a top hole penetrating the top sheet in a thickness direction,
5. The absorbent article according to any one of claims 1 to 4, wherein the position of the top sheet in which the top hole is formed and the position of the concave portion of the intermediate sheet overlap in plan view. the diameter of the top hole formed in the top sheet is larger than the diameter of the intermediate hole formed in the intermediate sheet;
In plan view, the top hole formed in the top sheet and the intermediate hole formed in the intermediate sheet at least partially overlap.
The absorbent article according to claim 5. the number of the top holes formed in the top sheet is greater than the number of the intermediate holes formed in the intermediate sheet;
In plan view, the top hole formed in the top sheet and the intermediate hole formed in the intermediate sheet at least partially overlap.
The absorbent article according to claim 5 or 6.

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