WO2012081282A1

WO2012081282A1 - Absorbent article

Info

Publication number: WO2012081282A1
Application number: PCT/JP2011/069662
Authority: WO
Inventors: 裕美立川; 達之山口; 加藤　隆弘; 長原　進介
Original assignee: 花王株式会社
Priority date: 2010-12-17
Filing date: 2011-08-30
Publication date: 2012-06-21
Also published as: KR101876595B1; CN103260564B; RU2568863C2; CN103260564A; RU2013132958A; KR20130124957A

Abstract

An oblong absorbent article having a liquid-permeable front surface sheet disposed on the skin-contacting side, a back surface sheet disposed on the side that does not contact the skin, and an absorbent disposed between the two sheets, wherein: the absorbent has a longitudinal direction and a width direction orthogonal thereto, and in the region that corresponds to the region of discharge, liquid-conducting structures are disposed in both the longitudinal and width directions of the absorbent that are configured from groove-shaped crevices excavated from the non-skin-contacting side in the thickness direction and pulp fiber-containing concave absorption parts at the bottoms of said crevices on the skin-contacting side; the regions surrounded by the liquid-conducting structures are provided with block-shaped protruding absorption parts that protrude to the non-skin-contacting side, contain pulp fibers and have higher basis weight than the concave absorption parts; and the concave absorption parts of the liquid-conducting structures are of low density and the block-shaped protruding absorption parts are of relatively high density.

Description

Absorbent articles

The present invention relates to absorbent articles such as sanitary napkins, disposable diapers, and incontinence pants.

In absorbent articles such as sanitary napkins, the material and structure of each member have been improved to improve its function and wearing feeling. Various proposals have also been made on improving the functionality of the absorber in accordance with the state of use and the type of article.

For example, a napkin having a top sheet, a back sheet, and an absorber has been proposed (see Patent Document 1) in which a large number of compressed parts that are depressed from the back sheet side of the absorber are scattered. The compressed portion and the uncompressed non-compressed portion gradually change in thickness to form continuous undulations, and a density gradient is formed from the non-compressed portion to the compressed portion. Thereby, the liquid guide | induced to the absorber from the surface sheet is drawn in quickly, and liquid return prevention property and anti-moisture property can be improved, implement | achieving sufficient absorption holding | maintenance amount of a liquid. Moreover, the absorbent article which has the absorber by which the high-density part and low-density part which are extended in the shape of a stripe in the vertical direction were divided alternately is indicated (refer to patent documents 2). By this absorber, the liquid diffusion in the vertical direction of the liquid is promoted, the liquid can be drawn easily, and it can be flexibly deformed by the pressure from the width direction.

JP 2006-55352 A JP 2010-136899 A

The present invention further enhances the absorption performance of the conventional absorbent article described above, more effectively suppresses liquid residue and liquid return to the top sheet, makes it less stuffy, and more excretion of bodily fluids. It is an object of the present invention to provide an absorbent article that can respond quickly and that fits the wearer's body and has excellent flexibility to follow the movement well.

The present invention relates to a vertically-long absorbent article having a liquid-permeable surface sheet disposed on the skin contact surface side, a back sheet disposed on the non-skin contact surface side, and an absorber disposed between both sheets. And the absorber has a longitudinal direction and a width direction orthogonal thereto,
In the region corresponding to the excretion part, in each of the longitudinal direction and the width direction of the absorbent body, a groove-like recess recessed in the thickness direction from the non-skin contact surface side, and the bottom of the recess on the skin contact surface side A liquid-permeable structure composed of a concave part absorbing part containing pulp fibers of
The region surrounded by the liquid-permeable structure is provided with a block-shaped protruding absorbent portion that protrudes toward the non-skin contact surface side and includes pulp fibers and has a higher basis weight than the recessed portion absorbent portion,
The recessed part absorption part of the said liquid-permeable structure is low density, and the said block-shaped protrusion absorption part is relatively high density The said subject is solved by the absorbent article.

The absorbent article of the present invention has the effect of suppressing liquid residue and liquid return to the top sheet more effectively and making it less stuffy. Furthermore, the absorbent article of the present invention has the effect of being able to respond quickly when there is more body fluid excretion, and to be fit to the wearer's body and excellent in flexibility to follow its movement well. .

The above and other features and advantages of the present invention will become more apparent from the following description with reference to the accompanying drawings as appropriate.

It is the partially notched perspective view which showed the sanitary napkin as one Embodiment of the absorbent article in this invention from the skin contact surface direction. It is the II-II sectional view shown in FIG. It is a figure which shows typically only the absorber which concerns on this embodiment, (A) is the top view which looked at the absorber from the skin contact surface side, (B) is the BB sectional view of (A) It is a figure and (C) is the top view which looked at the absorber from the non-skin contact surface side. It is process explanatory drawing which outlines and shows the state before and behind the press roll process at the time of manufacture about the preferable manufacturing method of the absorber which concerns on this embodiment. It is sectional drawing which shows typically the process in which an absorber precursor is formed in the recessed part for accumulation | storage on a rotating roll surface about the preferable manufacturing method of the absorber in this embodiment. It is the partially notched perspective view which showed the sanitary napkin as other embodiment (2nd Embodiment) of the absorbent article in this invention from the skin contact surface direction. It is the II-II sectional view taken on the line shown in FIG. It is the partial cross section figure which expanded and showed a part of predetermined cross section of the sanitary napkin shown in FIG. It is the partially cutaway perspective view which showed the sanitary napkin as other embodiment (3rd Embodiment) of the absorbent article in this invention from the skin contact surface direction. FIG. 11 is a cross section taken along line II-II shown in FIG. 9. It is the top view which showed typically the absorber of the sanitary napkin shown in FIG. 9 from the non-skin contact surface side. It is the partial cross section figure which expanded and showed a part of predetermined cross section of the sanitary napkin shown in FIG. It is a schematic sectional drawing which shows a part of form of the absorber manufactured in the reference example and the comparative example.

Hereinafter, the present invention will be described in detail based on preferred first to third embodiments with reference to the drawings.
[First Embodiment]
FIG. 1 is a partially cutaway perspective view showing a sanitary napkin as a first embodiment of an absorbent article according to the present invention from the skin contact surface direction, and FIG. 2 is a cross-sectional view taken along the line II-II shown in FIG. is there. FIG. 3 is a view schematically showing only the absorbent body according to the first embodiment, (A) is a plan view of the absorbent body as seen from the skin contact surface side, and (B) is B of (A). -B is a cross-sectional view taken along line B, and (C) is a plan view of the absorbent body as seen from the non-skin contact surface side. In addition, in order to avoid complexity in these drawings, the core wrap sheet of the absorber is omitted. Further, in FIG. 3, the leakage preventing groove is omitted for understanding the shape of the absorber.

In the sanitary napkin 10 of the present embodiment, the absorbent body 3 is joined and disposed on the skin contact surface side of the back sheet 2 with an adhesive or the like. Further, the side sheet 4 is in contact with and joined to the back sheet 2 outside the left and right sides of the absorbent body 3 on the skin contact surface side of the back sheet 2. The surface sheet 1 is sandwiched between the back sheet 2 and the side sheet 4 at the portion where the back sheet and the side sheet are in contact, and the top sheet 1 is further inward in the width direction (X direction) than the absorber 3. It arrange | positions so that it may be located in the skin contact surface side. The sheet members thus laminated are joined by heat sealing or the like outside the absorber 3 without the absorber 3 interposed therebetween, thereby forming the outer peripheral edge 6 of the napkin 10. The outer peripheral edge 6 is joined to such an extent that the overall stretchability is not hindered and the liquid once absorbed does not leak. A pocket (not shown) directed to the outer peripheral edge 6 is formed at the free end 41 of the side sheet 4 and has an effect of preventing lateral leakage of liquid or the like. In the present embodiment, wing portions 42 having side seats 4 extend outward in the width direction of the sanitary napkin 10 on both left and right sides of the sanitary napkin 10 in the width direction. The sanitary napkin 10 is fixed to the shorts by being wound around the non-skin contact surface side of the crotch.

On the skin contact surface side of the sanitary napkin 10, a leak-proof groove 5 squeezed from the skin contact surface side of the topsheet 1 to the absorber 3 is provided (see FIGS. 1 and 2). The plan view shape of the leak-proof groove 5 is such that, in the central portion in the longitudinal direction of the absorbent body 3, compressed portions having lengths in the longitudinal direction are arranged on the left and right sides in the width direction of the excretory part corresponding region such as menstrual blood. As the squeezed portion approaches the front and rear ends of the absorbent body 3, it gradually curves toward the center of the absorbent body 3, and coincides with the front end and the rear end. In other words, the leak-proof groove 5 has a shape in which two compressed portions arranged on the skin contact surface side on both sides in the longitudinal direction of the sanitary napkin 10 in the plan view extend in the front-rear direction and are continuous in an endless ring shape. Yes (see FIG. 1).
By doing in this way, the side leakage of the excretion liquid at the time of mounting | wearing and using a napkin can be prevented effectively. In addition, the excretory part corresponding | compatible area | region is the part which receives excretion of menstrual blood or a thing directly, and its vicinity, In the napkin 10 of this embodiment, it is a center part of the vertical direction, and is the position where the wing part 42 is arranged. is there. Moreover, the planar view shape of the leak-proof groove 5 in this embodiment is not limited to the above-mentioned shape, and may intersect with each other at the front end and the rear end of the endless annular shape, and is preferably determined appropriately according to the application.

Details regarding the materials and dimensions of the top sheet 1, the back sheet 2, the side sheet 4, and the absorber 3 will be described later. In the present embodiment, the surface sheet 1 uses a hydrophilic air-through nonwoven fabric from the viewpoint of promptly absorbing the excreted liquid and transmitting it to the absorber and from the viewpoint of good touch. Further, as the back sheet 2, a breathable moisture permeable film is used as a single layer. The absorbent body 3 is formed by coating pulp fibers or the like and a super absorbent polymer with a core wrap sheet (not shown) such as paper. Moreover, the adhesive (not shown) for fixing the sanitary napkin 10 to clothing is applied to the non-skin contact surface side of the back sheet 2. The sanitary napkin 10 is adhesively fixed to the user's clothes by the adhesive. The sanitary napkin 10 according to this embodiment is a line in which the top sheet side is directed to the wearer's skin contact surface side, the longitudinal direction is arranged from the lower abdomen to the buttocks, and the width direction is connected to the left and right feet. Arrange for the direction of and wear.

In the present invention, unless otherwise specified, the surface in contact with the human body is referred to as the skin side surface or skin contact surface or surface, and the opposite surface is referred to as the non-skin surface or non-skin contact surface or back surface. Of these two surfaces, the side close to the skin side or the extending direction is called the skin side, the skin contact surface side or the surface side, and the side close to the non-skin surface or the extending direction is the non-skin side, non-skin It is called the contact side or the back side. The direction positioned on the front side of the human body when worn is referred to as the front, and its end is referred to as the front end, and the direction positioned on the rear is referred to as the rear, and the end is referred to as the rear end. The normal direction of the front or back surface of the absorbent article is called the thickness direction, and the amount is called thickness. Furthermore, in the plan view of the absorbent article, a direction from the abdominal side to the back side through the crotch is referred to as a vertical direction, and a direction orthogonal to the vertical direction is referred to as a width direction. The vertical direction typically coincides with the front-rear direction of the human body when worn.

The absorbent body 3 of the present embodiment is obtained by coating a mixed product of pulp fibers and a superabsorbent polymer with a core wrap sheet. The absorbent body 3 has a low density of the absorbent material compared to the high density area 38 in which the absorbent body material (constituent fibers and superabsorbent polymer) exists in a dense state at least in the excretory part corresponding area. And a low-density region 39 that exists in such a state. As shown in FIG. 3A, the sea-island structure in which the low density regions 39 are continuous in the plane direction and the high density regions 38 are surrounded by the low density regions 39 is scattered.
In the thickness direction of the low density region 39, as shown in FIG. 3 (B), the concave portion 31 and the skin contact that become a void by being depressed from the non-skin contact surface side of the absorbent body 3 to the skin contact surface side. The recessed part absorption part 34 containing the pulp fiber in the bottom part of a contact surface side is distribute | arranged. As shown in FIGS. 3B and 3C, the recesses 31 are arranged in the longitudinal direction and the width direction on the non-skin contact surface side of the absorber, corresponding to the low density region 38. The arrangement in the vertical direction and the width direction means that a plurality of recesses 31 are arranged at predetermined intervals in a plan view of the absorber 3. Accordingly, the rows of recesses extending in the vertical direction are aligned and arranged at predetermined intervals in the width direction, and the columns of recesses extending in the width direction are aligned and arranged at predetermined intervals in the vertical direction.
Note that the rows of the recesses 31 may be continuous or intermittent. As shown in FIGS. 3A and 3B, the recess absorbing portion 34 is arranged corresponding to the recess 31. The recessed portion 31 and the recessed portion absorbing portion 34 draw the liquid on the skin surface side of the absorbent body 3 in the thickness direction quickly and effectively promote liquid holding and fixing to the protruding absorbing portion 33 without returning the liquid. It becomes a structure. This point will be described later. Further, in the thickness direction of the high-density region 38, a portion surrounded by the recess 31 is partitioned as a plurality of block-shaped protruding absorbing portions 33 protruding toward the back sheet 2 side (FIGS. 3B and 3C). )reference). The protrusion absorption part 33 absorbs and holds excretion liquid including pulp fibers and a water-absorbing polymer.
In this embodiment, the shape of each protrusion absorption part 33 is a substantially rectangular parallelepiped shape which has length in the vertical direction. The protrusions 33 are arranged in the vertical and horizontal directions so as to have predetermined gaps s and r (see FIG. 3C) in a natural state when viewed from the non-skin contact surface side of the absorber 3. Aligned. This arrangement is an arrangement in which the projected images overlap in any direction when a large number of protruding absorbers 33 are projected in the vertical and width directions. The entire absorbent body 3 including the recessed portion absorbing portion 34 and the protruding absorbing portion 33 has a seamless integrated structure.

The protruding absorbent portion 33 disposed in the high-density region 39 is a portion having a high basis weight that is thicker than the recessed portion absorbing portion 34 because the density of the absorbent body material is higher than that of the recessed portion absorbing portion 34 and the capillary force is higher. Therefore, the absorption retention amount of the liquid is also high. That is, the protrusion absorbing portion 33 mainly has a function of holding and fixing the liquid. On the other hand, the recessed portion absorbing portion 34 disposed in the low density region 38 is a portion having a low basis weight that is relatively lower in density than the protruding absorbing portion 33 and is thinner than the protruding absorbing portion 33. Therefore, the recessed portion absorbing portion 34 has a lower liquid flow resistance than the protruding absorbing portion 33 and can quickly transmit the liquid in the thickness direction of the absorber 3 without impairing the pressure loss of the liquid.
If this point is demonstrated with reference to FIG.3 (B), compared with the high-density area | region 38 of the absorber 3 with which the protrusion absorption part 33 is arrange | positioned, it is the absorber of the absorber with which the recessed part 31 and the recessed part absorption part 34 are arranged. The basis weight of the low density region 39 is low and the density is also low. The recessed portion absorbing portion 34 quickly draws in the liquid (FIG. 3B, arrow a ₁ ), and the plurality of adjacent protruding absorbing portions 33 further draw out the liquid by its capillary force (FIG. 3B, arrow c ₁ ). The liquid can be held and fixed at a position farther from the skin surface side of the absorber 3.

Further, the concave portion absorbing portion 34 and the portion 33a on the skin contacting surface side of the protruding absorbing portion 33 are continuous in the plane direction to form a continuous portion 35 on the skin contacting surface side of the absorbent body 3 (see FIG. 3B). . The continuous portion 35 has a flat shape with respect to the top sheet 1. Since the flat continuous portion 35 forms the skin contact surface side of the absorbent body 3, the contact between the topsheet 1 and the absorbent body 3 is good, and the liquid that has passed through the topsheet 1 is easily guided to the absorbent body 3.
The continuous portion 35 will be described with reference to FIG. 3A. As described above, the continuous portion 35 includes a low-density region 39 including the recessed portion absorbing portion 34 and a high-density region 38 including the portion 33a of the protruding absorbing portion 33. It is divided into. In the continuous portion 35, a low density region 39 composed of the low-basis weight and low-density recessed portion absorbing portion 34 serves as a liquid introduction path with a reduced liquid holding amount, and the low-density region 39 is continuous in the planar direction of the absorber 3. As a result, the liquid from the surface sheet 1 can be quickly drawn into the absorbent body 3 in a wide range (arrow b _{1 in} FIG. 3A).

The liquid that has passed through the recess absorbing portion 34 is dispersed, drawn, held, and fixed to the plurality of protruding absorbing portions 33 (FIG. 3 (B) arrow c ₁ ), and once taken into the recess 31 (FIG. 3). (B) an arrow _c 2). The liquid taken into the concave portion 31 is absorbed and held by the protruding absorption portion 33. Of course, the liquid can also be directly absorbed and held from the portion 33a of the protruding absorbing portion 33 (the portion of the continuous portion 35). However, when a highly viscous liquid such as menstrual blood is excreted in large quantities or repeatedly excreted at a time, even if it cannot be absorbed and retained by the projecting absorbent part 33 at a time, the concave part absorbent part 34 is quickly pulled in and the concave part 31 is absorbed. Fulfills the buffer function of temporarily holding the liquid. Moreover, as described above, the recess 31 is connected on the non-skin contact surface side of the absorbent body 3 (see FIG. 3C), thereby moving the liquid in a plane direction at a position farther than the top sheet 1. (FIG. 3 (C) arrow d ₁ ), and can be reliably absorbed and held by the plurality of protruding absorbing portions 33 scattered in a wide range (FIG. 3 (C) arrow d ₂ ).
As described above, the liquid passing structure including the recessed portion absorbing portion 34 and the recessed portion 31 allows the liquid to be quickly taken into the absorbent body 3 from the surface sheet 1 side and reliably absorbed and held by the protruding absorbing portion 33. As a result, the remaining liquid on the skin contact surface side of the absorbent body 3 is suppressed, and liquid return from the interior of the absorbent body 3 to the top sheet 1 is unlikely to occur.

In the napkin 10 of the present embodiment, even if there is a pressure in the thickness direction during wearing, excretion fluid such as menstrual blood is unlikely to return to the topsheet 1 side. This is because the sea-island structure in which the above-described high-density region 38 exists in the low-density region 39 does not leave any liquid on the skin contact surface side of the topsheet or the absorbent body 3 and quickly draws it in the thickness direction. One factor is to hold and fix the protrusions 33 on the plurality of protrusions. In addition to this, the liquid passing structure composed of the recess absorbing portion 34 and the recess 31 described above promotes the drawing and movement of the liquid, and effectively acts to suppress the liquid return.
Specifically, the concave portion absorbing portion 34 quickly draws into the concave portion 31 without holding the liquid, and the continuous density formed by the concave portion absorbing portion 34 that is the low density region and the protruding absorbing portion 33 that is the high density region 38. Due to the change (structural arrangement capable of diffusing a high amount of liquid), the liquid that cannot be drawn into the recess due to moderate diffusivity is quickly diffused in the plane direction, and the liquid once drawn into the recess 31 is the skin contact surface of the absorbent body 3 Since the liquid is rapidly moved on the non-skin contact surface side of the absorbent body 3 and is absorbed and held in the protruding absorbent portion 33 by the liquid passage structure having the concave portion 31, the concave portion 31 itself is stored. It is thought to be caused by a plurality of actions such as the amount not increasing. Further, it is considered that one of the factors is that the pressure applied to the concave portion 31 is eased by the presence of the concave portion absorbing portion 34, and that the movement of the liquid in the liquid passage structure having the concave portion 31 is promoted by this pressure.
Furthermore, since the absorbent body 3 is configured to support the skin contact surface to the non-skin contact surface with the protruding absorbing portion 33 of the high-density region 38, deformation with respect to pressure in the thickness direction hardly occurs. It is effective in suppressing return and preventing twisting. Thus, the liquid 3 is quickly drawn into the recess 31 without leaving the liquid on the surface sheet 1 side of the absorbent body 3, so that the return of the liquid to the surface sheet 1 side is effectively suppressed even in the thickness direction pressure, and a good dry feeling is achieved. Is obtained. Further, since the non-skin surface side of the absorbent body 3 has a concavo-convex shape defined by vertical and horizontal concave portions 31, the portion has flexibility in the vertical direction and the width direction, and the sanitary napkin 10 is used to undulate the skin surface. The “body compatibility” that fits and the movement of the wearer follow well, and the “motion followability” that prevents a partial gap from occurring on the skin is extremely high.
In the present invention, the arrangement of the protruding absorbing portions 33 can be selected as appropriate according to the application and function in addition to those of the present embodiment. For example, a staggered arrangement (the projected image is in the vertical direction and / or the width direction). (Arrangement with a substantially half-pitch deviation). Moreover, the shape of the protrusion absorption part 33 other than the thing of this embodiment can employ | adopt the thing of arbitrary shapes according to a use or a function suitably.

In this way, the recessed portion absorbing portion 34 suppresses the amount of liquid retained and quickly moves the liquid to the recessed portion 31, and the recessed portion 31 has a function of temporarily storing excretory liquid so that the liquid does not return to the topsheet 1 side. The average density (m ₁ ) of the constituent members of the absorbent body of the recess absorbing portion 34 as the low density region 39 is preferably 0.02 to 0.09 g / cm ^{3, and} more preferably 0.03 to 0.08 g / cm ^3. preferable. Further, in order to securely hold and fix the liquid, the average density (m ₂ ) of the constituent members of the absorbent body of the protruding absorbent portion 33 as the high-density region 38 is preferably 0.10 to 0.25 g / cm ³ , More preferably, it is 0.10 to 0.20 g / cm ³ . The protruding absorbing portion 33 is a portion that is densified by compression during manufacturing, but even if a uniform density is not formed in the thickness direction, the protruding absorbing portion 33 as a whole has a higher density than the recessed portion absorbing portion 34. The ratio (m ₁ / m ₂ ) between the average density (m ₁ ) of the recess absorbing part 34 as the low density region 39 and the average density (m ₂ ) of the protruding absorbing part 33 as the high density region 38 is 0. .80 or less is preferable, and 0.60 or less is more preferable. By setting the ratio (m ₁ / m ₂ ) to the upper limit or less, the liquid is temporarily held in the low density region 39 and the high density region 38 is made efficient by the capillary force acting between the high density region 38. Absorption mechanism that sucks and holds liquid well is developed.
For the same reason, the average basis weight (w ₁ ) of the constituent members of the absorbent body in the low density region 39 (see FIG. 3B) having the recessed portion absorbing portion 34 and the recessed portion 31 is 10 to 160 g / m ^2. It is preferably 20 to 150 g / m ² . The average basis weight (w ₂ ) of the constituent member of the absorbent body in the high-density region 38 (see FIG. 3B) having the protruding absorbent portion 33 is preferably 160 to 400 g / m ² , and 200 to 350 g / m ^2. it is more preferably m ^2. Furthermore, the average basis weight ratio (w ₁ / w ₂ ) of the constituent members of both absorbers is preferably 0.01 to 0.90, and more preferably 0.1 to 0.7. The ratio (%) (see FIG. 2) of the depth (h ₂ ) of the recess 31 to the thickness of the absorber 3 (thickness of the protruding absorber 33) (h ₁ ) (see FIG. 2) is preferably 20 to 98%. More preferably, it is ˜70%.

In the present invention, the concave portion 31 is a portion that is recessed from the bottom of the absorbent body 3 to the skin contact surface side to form a gap. The recessed part absorption part 34 is a part of the absorber 3 located in the upper part of the recessed part 31, Comprising: It is a part of the absorber 3 divided by the virtual lines t and t extended in the thickness direction from wall surface

bottom part

31a, 31a. (See FIG. 3B). The protrusion absorbing portion 33 is a portion of a region 38 adjacent to the region 39 of the recessed portion 31 and the recessed portion absorbing portion 34 arranged in the thickness direction and surrounded by the region 39 from the top to the bottom of the absorber (FIGS. 2 and 3). B)).

[Measuring Method of Average Density of High Density Region 38 and Low Density Region 39]
In the above definition, the density of the high-density region 38 and the low-density region 39 is a density obtained by combining pulp fibers that are constituent members of the absorbent body 3 and a highly water-absorbing polymer. The absorber 3 is cut by virtual lines t, t extending in the thickness direction from the wall

surface bottom portions

31a, 31a of the recess 31 to form a protruding absorption portion 33 of the high density region 38 and a recess absorption portion 34 of the low density region 39, These are cut out to a size of 50 mm in length and 5 mm in width to prepare samples. Subsequently, the mass of the sample is measured using an electronic balance (Electronic balance GR-300 manufactured by A & D, accuracy: 4 digits after the decimal point). Using a constant-pressure thickness meter, the sample thickness is measured, and the measured sample mass is divided by the volume of the sample (thickness × length × width) to calculate the density of all the materials in each region in each region. The measurement pressure of the low-pressure thickness gauge is 0.5 g / cm ² . The average density can be obtained by adjusting 10 samples at arbitrary locations and averaging them.

[Measurement Method of Average Basis Weight of High Density Region 38 and Low Density Region 39]
Method of measuring the average basis weight of high-density regions 38 average basis weight of (w ₂₎ and the low-density region 39 (w ₁₎ is an area of each region to be measured is measured in advance, the virtual line described above the measurement region Cut with a cutter at t, t and measure the mass of the cut part. The measured mass is divided by the area, and the average basis weight of each density region is measured. The average basis weight is obtained by adjusting 10 samples at an arbitrary position and averaging them.

[Measurement of Thickness of Protrusion Absorber 33 and Concave Absorber 34 (and Concave 31)]
First, the recess 31 can be classified as a portion having a gap that is recessed from the bottom of the absorber 3 toward the skin contact surface side, and the recess absorption portion 34 can be classified as a portion made of the material of the absorber 3 located above the recess 31 (see FIG. 3 (B)). The protruding absorbing portion 33 can be classified as a portion from the top to the bottom made of the material of the absorber 3 surrounded adjacent to the low density region 39 of the recessed portion 31 and the recessed portion absorbing portion 34 arranged in the thickness direction (FIG. 3B). ). The boundaries between the protruding absorbing portion 33 and the recessed portion absorbing portion 34 and the recessed portion 31 can be defined as virtual lines t and t extending in the thickness direction from the wall

surface bottom portions

31a and 31a of the recessed portion 31 (FIG. 3B).
Measurement of the thus partitioned is concave absorbing portion 34 thickness _{_{_{(h 3 = h 1 -h 2}}} ) the thickness of the projecting absorbing portion 33 _{(h 1),} the size of 37 mm × 37 mm, an acrylic plate having a thickness of 3mm absorption Place on the body 3, measure the thickness (h ₁ ) of the projection absorbing portion 33 using a non-contact type laser displacement meter (Laser Head LK-G30, Displacement Meter LK-GD500) manufactured by KEYENCE, and measure the thickness of the recessed portion absorbing portion 34. (H ₃ ) was measured by using a microscope VHX-1000 manufactured by KEYENCE to obtain a cross-section corresponding to FIG. 2 of the absorber.

Next, the preferable manufacturing method of the sanitary napkin 10 mentioned above is demonstrated with reference to FIG. In addition, the shape of the absorber 3, the number of concave portions 31 and the number of protruding absorbing portions 33, the shape, the arrangement, and the like are schematically illustrated, and may not necessarily be the same as those illustrated in FIGS.
FIG. 4 is a diagram showing an absorbent body manufacturing apparatus 60 preferably used for manufacturing the absorbent body 3 of the sanitary napkin 10. As shown in FIG. 4, the manufacturing apparatus 60 includes a rotating drum 62 in which a plurality of accumulation recesses 9 (deposition portions) are formed at predetermined intervals on the outer peripheral surface, and a fiber material toward the outer peripheral surface of the rotating drum 62. A duct 63 for supplying S in a scattered state, a fiber material supply unit 64 for supplying the fiber material S to the duct 63, and a scuffing roll 65 for scraping off an excessive amount of fiber material deposited so as to overflow the accumulation recess 9. And a covering mechanism (not shown) for covering the upper and lower surfaces of the deposit (absorber precursor) 70 released from the accumulation recess 9 with the core wrap sheet 3b, and the absorber precursor 70 with the core wrap sheet 3b. The absorber continuous body obtained by coating is compressed between a pair of press rolls 66a and 66b and compressed, and the compressed absorber continuous body is dimensioned to be used for each sanitary napkin. Absorber 3 after cutting and processing A cutting device (not shown).

The rotary drum 62 has a cylindrical shape and is driven to rotate at a constant speed in the direction of arrow A in FIG. A plurality of accumulation recesses 9 are formed on the outer peripheral surface of the rotary drum 62. An intake fan (not shown) is connected to a non-rotating portion inside the rotating drum 62 (on the rotating shaft side), and the partitioned spaces B and E inside the rotating drum are negatively driven by driving the intake fan. Maintained at pressure. The bottom surface portion of each collecting recess 9 is formed of a mesh plate and has a large number of pores. While the individual accumulation recesses 9 pass through the spaces B and E maintained at a negative pressure, the pores at the bottom of each accumulation recess 9 function as suction holes.

The duct 63 has a blowing end portion 63 a that covers a part of the outer peripheral surface of the rotating drum 62, and a blowing end portion 63 b connected to the fiber material supply device 64, and is a stacking recess located on the space B. 9 is configured to generate an air flow that flows toward the outer peripheral surface of the rotating drum 62 in the duct 63 by suction from the bottom surface portion of the rotating drum 9. The fiber material supply unit 64 includes a defibrator 64e, and a sheet-like raw material S 'such as a pulp sheet is introduced into the defibrator 64e by a nip roller 64d for supplying the raw material, and the defibrated fiber material S is ducted. It is comprised so that it may supply in 63.

The scuffing roll 65 has a brush around it, and scrapes off the fiber material S overflowing from the accumulation recess 62 with the brush. The deposit (absorber precursor) 70 that is not scraped off by the scuffing roll 65 and remains in the accumulation recess 9 is released from the accumulation recess 9 below the rotating drum 62. The mold release from the accumulation recess 9 maintains the partitioned space D in the rotary drum 62 at a positive pressure by a pressure means (not shown), and blows out air from the pores on the bottom surface of the accumulation recess 9. , By suction from the vacuum conveyor 67 side. The covering mechanism includes a well-known transport mechanism for supplying the core wrap sheet 3b on the vacuum conveyor 67, and a deposit (absorber precursor) 70 placed on the core wrap sheet. Both side portions are folded on the deposit (absorber precursor) 70, and the upper and lower surfaces of the deposit (absorber precursor) 70 are covered with the core wrap sheet 3b. In FIG. 4, the details of the folding process are omitted, and the state of the folded core wrap sheet 3b is simply shown as two lines.

A method for manufacturing the above-described absorber 3 using the absorber manufacturing apparatus 60 shown in FIG. 4 will be described.
First, the rotary drum 62 and the scuffing roll 65 are rotated, and the intake fan and the pressurizing unit are operated to make the spaces B and E have a negative pressure and the space D have a positive pressure. Further, the vacuum conveyor 67, the compression device 66, and the cutting device are operated. By the operation of the intake fan, a suction force is generated on the bottom surface of the accumulation recess 9 located on the space B, and an air flow that flows toward the outer peripheral surface of the rotary drum 62 is generated in the duct 63. Then, when the fiber material supply device 64 is operated to supply the fiber material S (pulp fiber 41 and the superabsorbent polymer 42) into the duct 63, the fiber material S is in a scattered state, and the inside of the duct 63 is discharged. It is placed on the flowing air stream and supplied toward the outer peripheral surface of the rotating drum 62.

While each collecting recess 9 passes through the space B maintained at a negative pressure, the fiber material S supplied from the duct 63 is sucked and accumulated in each collecting recess 9. A slightly excessive amount of fiber material is deposited on each accumulation recess 9, and the fiber material overflowing from the accumulation recess 9 is scraped off by the scuffing roll 65. The deposit (absorber precursor) 70 that has not been scraped off by the scuffing roll 65 and remains in the accumulation recess 9 is released onto the core wrap sheet 3 b supplied onto the vacuum conveyor 67.

The formation of the absorber precursor 70 will be described with reference to FIG. In FIG. 5, in order to understand the undulations of the absorber shape, a portion where two protrusions 51 are arranged is cut out and illustrated instead of the entire accumulation recess 9.
5A, the fiber material S, which is a mixture of the pulp fiber 41 and the superabsorbent polymer 42, is stacked by further dividing the protrusion 51 of FIG. 5A. When gradually deposited, the fibers are stacked beyond the height of the protrusion 51 as shown in FIG. 5B, and the absorber precursor 70 shown in FIG. 5C is obtained. A portion 74 deposited on the protruding portion 51 becomes the recessed portion absorbing portion 34 of the absorber 3, and a portion 71 where the protruding portion 51 is formed becomes the recessed portion 31 of the absorber 3. The portion 73 accumulated in the concave portion for accumulation between the protrusions becomes the protrusion absorbing portion 33 ′ before being compressed. And the part 75 piled up higher than the projection part 51 becomes the continuous part 35 of the absorber 3. FIG.

The deposit (absorber precursor) 70 on the core wrap sheet 3b is covered with both sides of the folded core wrap sheet 3b, and then introduced into the compression device 66 to be added between the pair of press rolls 66a and 66b. Pressed. Thereby, protrusion absorption part 33 'is compressed and shape | molded as the protrusion absorption part 33 of a high-density area | region. Then, it cut | disconnects with the cutting means which is not shown in figure, and becomes the absorber 3 of the dimension used for each sanitary napkin. The pressurizing method may be a method of compressing with a flat press machine in addition to the press roll 66. Regardless of the compression means, the conditions for pressurizing is preferably 0.5 ~ 5kgf / cm ^2, more preferably 1 ~ 4kgf / cm ^2.
In this way, the absorbent body 3 is integrally molded, and irregularities are formed in accordance with the shape and arrangement of the protrusions 51 in the recesses for accumulation. The recessed portion absorbing portion 34 has a lower basis weight than the protruding absorbing portion 33 due to its thin thickness, and unlike the recessed portion absorbing portion 34 formed by squeezing such as embossing, the recessed portion absorbing portion 34 has a low resistance to liquid passage. It is easy to make a quick transition in the thickness direction. Moreover, since the absorber 3 integrally formed in this way does not have a part hardened by pressing, such as embossing, the touch becomes good. When the napkin 10 having the absorbent body 3 is attached, there is no portion that hardly hits through the top sheet 1 and the softness of the absorbent body 3 can be realized. And since it has flexibility in the part of the recessed part 31, it fits to a body and a favorable mounting feeling is obtained.

In the present embodiment, the superabsorbent polymer inside the absorbent body 3 exists uniformly, but in order to more effectively suppress liquid return, the superabsorbent polymer is more than the continuous portion 35 including the recessed portion absorbent portion 34. It is preferable that the protrusion absorbing portion 33 is arranged with a large amount of deviation, and it is more preferable that the protruding absorption portion 33 is arranged with a large amount of deviation toward the non-skin surface side than the continuous portion 35 including the concave portion absorbing portion 34. It is also preferable from the same viewpoint to dispose a highly water-absorbing polymer on the non-skin surface side of the recess 31.
Furthermore, in the absorbent body 3 of the present embodiment, it is preferable that the liquid passage structure having the recess 31 extends to the outer portion of the leak-proof groove 5 in the width direction. By this arrangement, both sides of the absorbent body 3 that is liable to cause side leakage are also given flexibility, can be deformed so as to surround the inside of the wearer's legs, and can be fitted to the crotch. It is possible to prevent a gap from occurring following the above.

The size and shape of the protruding absorbing portion 33 and the recess 31 according to this embodiment is not particularly limited, slightly varies depending application of the absorbent article to be used, the longitudinal length k _{1 (FIG.} 3 of the projecting absorbing portion 33 ( C) is preferably 5 to 40 mm, more preferably 10 to 25 mm. The width direction length k ₂ is preferably 3 to 40 mm, and more preferably 5 to 15 mm. Further, the longitudinal length s of the recess 31 is preferably 1 to 5 mm, and more preferably 1 to 3 mm. The width direction length r is preferably 1 to 5 mm, and more preferably 1 to 3 mm.

[Second Embodiment]
Next, a sanitary napkin as a second embodiment of the absorbent article in the present invention will be described with reference to FIGS. FIG. 6 is a partially cutaway perspective view showing a sanitary napkin as a second embodiment of the absorbent article according to the present invention from the skin contact surface direction. FIG. 7 is a cross-sectional view taken along line II-II shown in FIG. FIG. 8 is a partial cross-sectional view showing an enlarged part of a predetermined cross section of the sanitary napkin shown in FIG.
Hereinafter, the second embodiment of the present invention will be described by omitting the same parts as those in the first embodiment. The first embodiment and the second embodiment are not independent and exclusive. For example, the second embodiment may be positioned as included in the subordinate concept of the first embodiment. it can. The invention according to the first embodiment and the invention according to the second embodiment have a technical relationship in which a single inventive concept is formed and linked based on the same or corresponding special technical features. The same reference numerals are given to the same members and the like, and the description may be omitted (however, dimensions and detailed positional relationships are in accordance with the drawings corresponding to the respective embodiments).

The sanitary napkin 20 of the second embodiment is different only in the surface sheet among the constituent members of the sanitary napkin 10 of the first embodiment. The surface sheet in 2nd Embodiment is shown as the code | symbol 21. FIG. The topsheet 21 has a number of parts that regularly protrude on the skin contact surface side and the non-skin contact surface side, and the protrusions are arranged at the same positions on the skin contact surface side and the non-skin contact surface side. (See FIGS. 6 to 8). The details of the topsheet 21 are as follows.

As shown in FIG. 7, the topsheet 21 of the present embodiment is formed by laminating two fiber layers of an upper layer 11 and a lower layer 12 from the skin contact surface side.
The upper layer 11 and the lower layer 12 are joined by crimping by embossing at a large number of embossed portions 15. The upper layer 11 and the lower layer 12 are embossed at the same position in plan view, and are recessed at the embossed portion 15 to form a number of valleys. A non-embossed portion between the valleys, that is, a region surrounded by the embossed portion 15 forms a protrusion 14. The protrusion 14a of the upper layer 11 protrudes toward the skin contact surface, and the protrusion 14b of the lower layer 12 protrudes toward the non-skin contact surface. The

protrusions

14a and 14b are regularly arranged in the same position on the upper layer 11 and the lower layer 12 in a plan view as in the embossed portion 15 described above. A large number of irregularities are formed over the entire area. And also as the whole surface sheet 21, many uneven | corrugated | grooved parts are formed over the whole region.
The embossed portion 15 that becomes the valley portion of the upper layer 11 and the lower layer 12 is a portion where the fibers of the topsheet 21 are consolidated, and has a higher fiber density and a higher capillary force than the protrusions 14 of the topsheet 21. Thereby, excretion liquid can be permeated | transmitted from the surface sheet 21 to the absorber 3 effectively quickly. Specifically, the means described in paragraphs [0007] to [0045] of the specification of JP-A No. 2004-166849 can be used.

In the present embodiment, each embossed portion 15 has a substantially cross shape in which two long axes intersect (see FIG. 6). Two adjacent

embossed portions

15, 15 at the shortest distance are arranged so as to exist on a substantially extended line in the major axis direction. As a result, a density gradient of the constituent fibers is formed between the embossed portion 15 and the protrusion 14 in the multi-direction on the top sheet 21, and the surface sheet 21 has liquid diffusion and liquid permeability in the thickness direction. Will be improved. The shape and arrangement of the embossed portion 15 may be arbitrarily dotted with circular or square embosses in addition to those of the present embodiment, and the diffusion and thickness of the liquid having a density gradient of constituent fibers. Any shape or arrangement that realizes quick transmission in the direction can be adopted.

Here, the characteristics of the dynamic action of the partitioned absorbent body 3 and the surface sheet 21 in the sanitary napkin 20 will be described in detail with reference to FIG. FIG. 8 is a partial cross-sectional view showing an enlarged part of a predetermined cross section of the sanitary napkin shown in FIG. In addition, in order to avoid complication of the figure, the back sheet 2 and the side sheet 4 are not shown, and the shape of the top sheet 21 is schematically shown. In the practice of the present invention, the shape is not necessarily the same as the illustrated shape. It doesn't have to be.

As described above, the surface sheet 21 has high liquid mobility in the thickness direction of the excreted liquid due to the capillary force utilizing the density gradient, and can quickly transfer the liquid excreted from the body to the absorber 3. it can. Further, the protrusion 14a of the upper layer 11 and the protrusion 14b of the lower layer 12 are formed at the same position in the thickness direction (see FIG. 8), so that the liquid can easily move so as to gather in one place in a plane. Even a small amount of liquid is preferable because it is guided to the absorber 3 and is effectively transmitted to the absorber 3 side. In particular, when the fiber density is different between the upper layer 11 and the lower layer 12 and the fiber density of the lower layer is high, the liquid tends to stay on the lower layer side of the surface sheet. And improved dry feeling due to low liquid return. As described above, the absorbent body 3 has the plurality of recesses 31 on the non-skin contact surface side, and the recess absorption part 34 is disposed on the skin contact surface side. The concave portion absorbing portion 34 has a lower liquid resistance than the other absorber portions, and the liquid a ₁ excreted using this portion as a chamber is quickly absorbed in the thickness direction of the absorber 3. A part of the liquid that has moved in the thickness direction of the absorber 3 becomes the transition liquid a ₂ toward the protruding

protrusions

33 and 33 around the periphery, and the other part becomes the storage liquid a ₃ that is taken into the recess 31. . Thus, the liquid that is transmitted from the topsheet 21 is pulled by the recesses absorbing portion 34, it is distributed into a ₂ and a _3, a holding amount of reduced flow-through resistance at the surface side of the absorbent body It will be even lower. Thereby, the liquid return to the surface sheet 21 can also be suppressed effectively.
As described above, the sanitary napkin 20 according to this embodiment has the performance of the top sheet 21 having high liquid permeability in the thickness direction, and the liquid permeability in the high thickness direction of the absorbent body 3 having the recess 31. Can be sufficiently exerted by this, thereby suppressing the return of the moisture taken in to the skin and giving the user a suitable dry feeling.

As described above, in the napkin 20, the top sheet 21 can be moved while concentrating the liquid, so that the remaining amount of liquid in the top sheet 21 can be reduced (improves dry feeling), and there are few parts that are in direct contact with the absorber 3. Return can be suppressed. Moreover, in such a surface sheet 21, when the low density area | region 39 and the high density area | region 38 of the absorber 3 are formed in the skin contact surface side, the recessed part absorption part of the low density area | region 39 is mentioned among the effects mentioned above. The dry feeling in the topsheet 21 can be further improved by the development of moderate diffusivity resulting from the continuous density change made by the projecting absorbent portion 33 of the high density region 38 and the high density region 38. Moreover, since the said continuous density change in the absorber 3 is formed only around the high-density area | region 38, excessive diffusivity does not express but it can suppress a leak.

The material of the surface sheet 21 and a preferable manufacturing method thereof will be described below.
The top sheet 21 is made of, for example, a non-heat-shrinkable fiber material or a heat-shrinkable fiber material before shrinkage having a higher heat-shrinkage temperature than that of the upper layer 11 and fibers having a heat-shrinkage temperature higher than that of the lower-layer fibers. It is composed of a lower layer 12.
After the upper layer 11 and the lower layer 12 are partially or wholly fused in a predetermined pattern by embossing such as heat, heat is applied to thermally contract the lower layer 12 in the horizontal direction. Then, since the upper layer 11 and the lower layer 12 are embossed and integrated, when the lower layer 12 contracts, since the upper layer 11 is integrated with the lower layer 12 by embossing, the upper layer 11 and the lower layer 12 try to shrink. However, the upper layer 11 is not thermally contracted or has a thermal contraction smaller than that of the lower layer 12, so that strain is generated, and this strain appears as a convex bulge in the upper layer 11. At the same time, since the strain of the upper layer 11 is transmitted to the lower layer 12 side, it also appears as a convex ridge on the lower layer 12. More specifically, for example, heat fusion by heat embossing is performed by using an embossed surface (such as a peripheral surface of an embossing roll) in which a large number of embossed pins having a predetermined shape are arranged in a predetermined pattern with the upper layer 11 and the lower layer 12. This is performed by pressing the upper layer 11 and the lower layer 12 in the laminated body, and melting the constituent fibers of the upper layer 11 and the lower layer 12 at the portions that are hot pressed by the pins. The protrusion 14 formed by the upper layer 11 and the lower layer 12 may have a portion protruding so as to cover the embossed portion.

The heat shrinkage of the lower layer 12 is, for example, configured by forming the lower layer 12 from heat-shrinkable fibers or including the heat-shrinkable fibers in the lower layer 12 and heat-bonding the upper layer 11 and the lower layer 12 or both. After the heat fusion, the intermediate layer 12 is heated. Thus, by thermally contracting the lower layer 12 in the horizontal direction, the bulge forming property of the convex portions formed on the upper layer 11 and the lower layer 12 is enhanced, and the topsheet 21 that is bulky and has a good touch can be obtained. When the surface sheet 21 is configured by laminating the two fiber layers in this way, from the viewpoint of improving the liquid permeability in the thickness direction of the surface sheet 21, between the two fiber layers. Preferably, no interface is formed.

As the upper layer 11 and the lower layer 12, for example, a web formed by a card method or a bulky nonwoven fabric is preferably used. The web formed by the card method is a fiber assembly in a state before being made into a nonwoven fabric. That is, a fiber assembly in which fibers are in an extremely loose entanglement state after being subjected to a post-treatment applied to a card web used for manufacturing a nonwoven fabric, for example, a heat-sealing treatment by an air-through method or a calendar method. It is the body. When the web formed by the card method is used as the upper layer 11 and the lower layer 12, the fibers in the upper layer 11 and the lower layer 12 are heat-fused simultaneously with or after the upper layer 11 and the lower layer 12 are bonded. . Further, as the bulky nonwoven fabric, the constituent fibers of the upper layer 11 such as air-through nonwoven fabric, air-laid nonwoven fabric, resin-bonded nonwoven fabric, etc. are substantially non-heat-shrinkable, or the thermal contraction temperature of the constituent fibers of the lower layer 12 In the following, it is preferable that it does not heat shrink. The basis weight of the upper layer 11 is preferably 10 to 50 g / m ² , more preferably 15 to 40 g / m ² from the viewpoint of forming a sufficient density gradient and improving the touch of the topsheet 21.

As the lower layer 12, a web formed by a card method or a non-woven fabric having heat shrinkability can be used. As the constituent fibers of the lower layer 12, those made of a thermoplastic polymer material and having heat shrinkability are preferably used. Examples of such fibers include latently crimpable fibers. The content ratio of the latent crimpable fibers in the lower layer 12 is preferably 40 to 100% by weight. The latent crimpable fiber can be handled in the same way as a conventional non-woven fabric fiber before being heated, and has a property that a helical crimp develops and shrinks when heated at a predetermined temperature. It is the fiber which has.

The latent crimpable fiber is composed of, for example, an eccentric core-sheath type or side-by-side type composite fiber composed of two types of thermoplastic polymer materials having different shrinkage rates. Examples thereof include those described in JP-A-9-296325 and Japanese Patent No. 2759331. The middle layer 12 includes, for example, such latently crimpable fibers, and simultaneously or after heat fusion with the upper layer 11 and the lower layer 12, the crimps of the fibers are expressed by heating and contracted. Can do. The basis weight of the middle layer 12 is preferably 10 to 50 g / m ² , more preferably 15 to 40 g / m ² .

The surface sheet 21 composed of the upper layer 11 and the lower layer 12 preferably has a basis weight of 20 to 100 g / m ² , more preferably 35 to 80 g / m ² . Since the surface sheet 21 is formed with a large number of uneven portions, the sheet 1 is large and bulky.

The surface sheet 21 is not limited to the above-described form, and can be appropriately changed without departing from the gist of the present invention. For example, the surface sheet 21 may be composed of a fiber sheet having a three-layer structure. In this case, it is desirable that the middle layer 13 is composed of fibers having heat shrinkability, and the upper layer 11 and the lower layer 12 are composed of fibers having no heat shrinkability. From the viewpoint of increasing the liquid permeability, it is desirable that the basis weight of the upper layer 11 is larger than the basis weight of the lower layer 12.

[Third Embodiment]
Next, still another embodiment (third embodiment) of the sanitary napkin of the second embodiment as the absorbent article of the present invention will be described below. The sanitary napkin of the third embodiment uses the absorbent body 3 together with the topsheet 21 of the second embodiment, and the area A of the protruding absorbent part 38 is set to have a higher basis weight than the area B of the recessed part absorbing part 34 and the recessed part 31. ing.
Note that the first and second embodiments and the third embodiment are not independent and exclusive, and are, for example, those included in the subordinate concepts of the first and second embodiments. Embodiments can be positioned. The inventions according to the first and second embodiments and the invention according to the third embodiment have a technical relationship in which a single inventive concept is formed and linked based on the same or corresponding special technical features. The same reference numerals are given to the same members and the like, and the description may be omitted (however, the dimensions and detailed positional relationship are in accordance with the drawings corresponding to the respective embodiments).

FIG. 9 is a partially cutaway perspective view showing the sanitary napkin as the third embodiment from the skin contact surface direction. 10 is a cross-sectional view taken along the line II-II shown in FIG. FIG. 11 is a plan view schematically showing the absorbent body of the sanitary napkin shown in FIG. 9 from the non-skin contact surface side, and members other than the absorbent body are not shown to avoid complication of the drawing. In addition, in order to avoid complexity in these drawings, the core wrap sheet of the absorber is omitted. FIG. 12 is a partial cross-sectional view showing an enlarged part of a predetermined cross section of the sanitary napkin shown in FIG. 9.

In the sanitary napkin 30 of the present embodiment, the absorbent body 3 is joined and disposed on the skin contact surface side of the back sheet 2 with an adhesive or the like. Further, on the skin contact surface side of the back sheet 2, the side sheet 4 is in contact with and joined to the back sheet 2 outside the left and right sides in the longitudinal direction of the absorber 3. At the portion where the back sheet and the side sheet abut, the top sheet 21 is sandwiched between the back sheet 2 and the side sheet 4, and the top sheet 21 is further inward in the width direction (X direction) than the absorber 3. It arrange | positions so that it may be located in the skin contact surface side. The sheet members thus laminated are joined to each other by heat sealing or the like without the absorbent body 3 interposed outside the absorbent body 3 to form the outer peripheral edge portion 6 of the napkin 30. The outer peripheral edge 6 is joined to such an extent that the overall stretchability is not hindered and the liquid once absorbed does not leak. A pocket (not shown) directed to the outer peripheral edge 6 is formed at the free end 41 of the side sheet 4 and has an effect of preventing lateral leakage of liquid or the like. In addition, the wing part 42 which has the side sheet | seat 4 is extended toward the width direction outer side of the sanitary napkin 30 in the width direction right and left both sides of the sanitary napkin 30 in this embodiment, and this part is shorts. The sanitary napkin 30 is fixed to the shorts by being wound around the non-skin contact surface side of the crotch.

A leak-proof groove 5 squeezed from the skin contact surface side of the top sheet 21 to the absorbent body 3 is provided on the skin contact surface side of the sanitary napkin 30. The plan view shape of the leak-proof groove 5 is such that, in the central portion in the longitudinal direction of the absorbent body 3, compressed portions having lengths in the longitudinal direction are arranged on the left and right sides in the width direction of the excretory part corresponding region such as menstrual blood. As the squeezed portion approaches the front and rear ends of the absorbent body 3, it gradually curves toward the center of the absorbent body 3, and the front end and rear end coincide with each other. That is, the leak-proof groove 5 has a shape in which two compressed portions arranged on the skin contact surface side on both sides in the longitudinal direction of the sanitary napkin 30 extend in the front-rear direction and are continuously endlessly annular in plan view. Yes (see FIG. 9). By doing in this way, the side leakage of the excretion liquid at the time of mounting | wearing and using a napkin can be prevented effectively. In addition, the excretory part opposing area | region is the part which receives excretion of menstrual blood or a thing directly, and its vicinity. Moreover, the planar view shape of the leak-proof groove 5 in this embodiment is not limited to the above-mentioned shape, and may intersect with each other at the front end and the rear end of the endless annular shape, and is preferably determined appropriately according to the application.

Details regarding the materials and dimensions of the top sheet 21, the back sheet 2, the side sheet 4, and the absorber 3 will be described later. In the present embodiment, the surface sheet 21 promptly absorbs the excreted liquid and transmits it to the absorbent body, and the protrusions made of fibers on the skin contact surface side and the non-skin contact surface side from the viewpoint of good touch. A liquid-permeable nonwoven fabric having Further, as the back sheet 2, a breathable moisture permeable film is used as a single layer. The absorbent body 3 is formed by coating pulp fibers or the like and an absorbent polymer with a core wrap sheet (not shown) such as paper. Moreover, the adhesive (not shown) for fixing the sanitary napkin 30 to clothing is applied to the non-skin contact surface side of the back sheet 2. The sanitary napkin 30 is adhesively fixed to the user's clothes by the adhesive. The sanitary napkin 30 according to this embodiment is a line in which the top sheet side is directed to the wearer's skin contact surface side, and the vertical direction is arranged from the lower abdomen to the buttocks, and the width direction is connected to the left and right feet. Arrange for the direction of and wear.

As shown in FIG. 10, the topsheet 21 of the present embodiment is formed by laminating two fiber layers, an upper layer 11 and a lower layer 12 from the skin contact surface side.
The upper layer 11 and the lower layer 12 are joined by crimping by embossing at a large number of embossed portions 15. The upper layer 11 and the lower layer 12 are embossed at the same position in plan view, and are recessed at the embossed portion 15 to form a number of valleys. A non-embossed portion between the valleys, that is, a region surrounded by the embossed portion 15 forms a protrusion 14. The protrusion 14a of the upper layer 11 protrudes toward the skin contact surface, and the protrusion 14b of the lower layer 12 protrudes toward the non-skin contact surface. The

protrusions

In the present embodiment, each embossed portion 15 has a substantially cross shape in which two long axes intersect. Two adjacent

embossed portions

The absorbent body 3 of the present embodiment is obtained by coating a mixed product of pulp fibers and a water-absorbing polymer with a core wrap sheet. The absorbent body 3 is provided with a plurality of recesses 31 that are recessed in the thickness direction from the non-skin contact surface side to the skin contact surface side at least in the excretory part corresponding region. The recess 31 is disposed in each of the longitudinal direction and the width direction of the absorber 3. The arrangement in the vertical direction and the width direction means that a plurality of concave portions 31 are arranged at a predetermined interval in a plan view of the absorber 3, and a row of the concave portions extending in the vertical direction is predetermined in the width direction. That is, the rows of recesses that are aligned at intervals and extend in the width direction are aligned at predetermined intervals in the vertical direction. Note that the rows of the recesses 31 may be continuous or intermittent. A concave portion absorbing portion 34 containing pulp fibers is disposed on the bottom portion of the concave portion 31 on the skin contact surface side. A plurality of recesses 31 arranged in a plurality of lengths and widths and the corresponding recess absorbing portions 34 are linked in the thickness direction to form a liquid passing structure of the absorber 3. The portion of the absorbent body 3 sandwiched between the recesses 31 is partitioned as a plurality of block-shaped protruding absorbing portions 33 protruding toward the back sheet 2 side. The protrusion absorption part 33 absorbs and holds excretion liquid including pulp fibers and a water-absorbing polymer. In this embodiment, the shape of each protrusion absorption part 33 is a substantially rectangular parallelepiped shape with a length in a longitudinal direction. The protrusions 33 are aligned in the vertical and horizontal directions so as to have predetermined gaps s and r (see FIG. 11) in a natural state when viewed from the non-skin contact surface side of the absorber 3. ing. This arrangement is an arrangement in which the projected images overlap in any direction when a large number of protruding absorbing portions 33 are projected in the longitudinal direction and the width direction. Due to the liquid passing structure having the concave portion 31 described above, liquid such as menstrual blood is moved to each protruding absorption portion 33 on the non-skin contact surface of the absorbent body 3 that is farther than the top sheet 21, and quickly absorbed and held. can do.

As described above, on the skin surface side of the recessed portion 31, the recessed portion absorbing portion 34 thinner than the protruding absorbing portion 33 is disposed as a part of the absorbent body 3. The concave portion absorbing portion 34 and the portion (upper portion) 33a on the skin contact surface side of the protruding absorption portion 33 are connected in the plane direction to form a continuous portion 35 on the skin contact surface side of the absorbent body 3. The continuous part 35 has a flat shape with respect to the top sheet 21. The entire absorbent body 3 including the recessed portion absorbing portion 34 and the protruding absorbing portion 33 has a seamless integrated structure. In particular, the density is substantially uniform as a whole except for the compressed portion of the leak-proof groove 5 in the excretory part corresponding region. That the density is substantially uniform means that there is no portion where the density is extremely increased such as compression by embossing when the absorber 3 is molded, This means that even a case where there is a slight density change due to the bias of the members at the time of product shipment such as folding by individual packaging. Moreover, the basis weight of the area | region B (FIG. 10) of the absorber where the recessed part 31 and the recessed part absorption part 34 are arrange | positioned compared with the area | region A (FIG. 10) of the absorber 3 where the protrusion absorption part 33 is arrange | positioned is made small. ing.

The absorbent body 3 of the present embodiment has a flat shape on the skin contact surface side of the absorbent body 3 having the continuous portion 35, so that the contact between the topsheet 21 and the absorbent body 3 is good and has passed through the topsheet 21. The liquid is easily guided to the absorber 3 in a wide range. As will be described later, the block-shaped protruding absorbing portion 33 and the recessed portion absorbing portion 34 are formed by connecting the recessed portion absorbing portion 34 and the upper portion 33a of the block-shaped protruding absorbing portion 33 in a planar shape on the skin contact surface side. In the boundary region between the recessed portion absorbing portion 34 and the block absorbing portion 33, there is no extreme difference in density as seen in a conventional compressed groove and the like, which is a substantially uniform density, and is composed of substantially the same material such as pulp fiber. The skin contact surface side is planar and planar, and the boundary is not visible.
And in the said liquid flow structure, since the density is not raised in the recessed part absorption part 34, and a basis weight becomes low because thickness is thin, the liquid flow resistance is low. Thereby, the recessed part absorption part 34 becomes a liquid introduction path which restrained the liquid holding | maintenance amount, and can draw in the liquid from the surface sheet 21 to the inside of the absorber 3 quickly. On the other hand, the liquid that has passed through the recess absorbing portion 34 easily moves to the upper portion 33a of the protruding absorbing portion 33 in the continuous portion 35 having a substantially uniform density without a boundary region, and is quickly taken in by the plurality of protruding absorbing portions 33 in the thickness direction. Moved to and held. On the other hand, the liquid in the recessed part absorption part 34 is once taken in also into the recessed part 31 which is a space part. The liquid taken into the concave portion 31 is absorbed and held near the lower portion of the protruding absorbing portion 33. Of course, the liquid can also be directly absorbed and held from the portion 33a of the protruding absorbing portion 33 (the portion of the continuous portion 35). However, when a highly viscous liquid such as menstrual blood is excreted in large quantities or repeatedly excreted at a time, even if it cannot be absorbed and retained by the projecting absorbent part 33 at a time, the concave part absorbent part 34 is quickly pulled in and the concave part 31 is absorbed. Fulfills the buffer function of temporarily holding the liquid. Moreover, as described above, since the recess 31 is connected on the non-skin contact surface side of the absorbent body 3, the liquid is moved at a position farther from the top sheet 21 and is reliably absorbed and held by each protruding absorber 33. Can be made. As described above, the liquid passing structure including the concave portion absorbing portion 34 and the concave portion 31 allows the liquid to be quickly taken into the absorbent body 3 from the surface sheet 21 side and reliably held by the protruding absorbing portion 33. As a result, liquid remaining on the skin contact surface side of the absorbent body 3 is suppressed, and liquid return from the interior of the absorbent body 3 to the surface sheet 21 hardly occurs.

Further, due to the liquid passing structure including the concave portion absorbing portion 34 and the concave portion 31, excretion fluid such as menstrual blood is unlikely to return to the topsheet 21 side even when there is pressure in the thickness direction when the napkin 30 is attached. This means that the recessed portion absorbing portion 34 quickly draws into the recessed portion 31 without holding the liquid, and the liquid once drawn into the recessed portion 31 is positioned relatively far from the skin contact surface side of the absorbent body 3. Due to the liquid passing structure having the recess 31, the liquid is quickly moved on the non-skin contact surface side of the absorbent body 3 and is absorbed and held in the protruding absorption portion 33, so that the storage amount of the recess 31 itself does not increase. It is thought to occur. Further, it is considered that one of the factors is that the pressure applied to the concave portion 31 is eased by the presence of the concave portion absorbing portion 34, and that the movement of the liquid in the liquid passage structure having the concave portion 31 is promoted by this pressure. Thus, by quickly drawing into the recess 31 without leaving the liquid on the top sheet 21 side of the absorbent body 3, the return of the liquid to the top sheet 21 side is effectively suppressed even in the thickness direction pressure, and a good dry feeling Is obtained. Further, since the non-skin surface side of the absorbent body 3 is a concavo-convex shape defined by vertical and horizontal concave portions 31, the portion has flexibility, and the sanitary napkin 30 fits the undulations on the skin. "And the movement of the wearer follow well, and the" motion followability "that prevents partial gaps from occurring on the skin is extremely high.
In the present invention, the arrangement of the protrusion absorbing portion 33 can be selected as appropriate according to the application and function in addition to those in the present embodiment. For example, a staggered arrangement (the projected image is in the longitudinal direction and / or the width direction). (Arrangement with a substantially half-pitch deviation). Moreover, the shape of the protrusion absorption part 33 other than the thing of this embodiment can employ | adopt the thing of arbitrary shapes according to a use or a function suitably. In addition, you may provide embossing from the surface sheet side of the said absorber of this invention, and may form a general leak-proof groove.

As a manufacturing method of the absorbent body 3, for example, an absorbent body material made of pulp fibers or pulp fibers and a superabsorbent polymer is scattered in the air, and a plurality of them are provided on a peripheral surface of a stacking drum or the like. It can be manufactured using a fiber stacker, a mixed fiber stacker, or the like that is sucked and deposited on the stacking portion of the mold 50 (see FIG. 5) having the protrusions 51 (not shown).
For example, as shown in FIG. 5, when the mixture of pulp fiber 61 and water-absorbing polymer 62 is piled up by separating the protrusions 51 in FIG. 5 (a) and gradually deposited, as shown in FIG. 5 (b). 5 (c), the absorber precursor 70 is formed. A portion 74 deposited on the protruding portion 51 becomes the concave portion absorbing portion 34 of the absorber 3, and a portion 71 having the protruding portion 51 becomes the concave portion 31 of the absorber 3. A portion 73 deposited in the concave portion for accumulation between the protrusions becomes the protruding absorption portion 33 of the absorber 3. And the part 75 piled up higher than the projection part 51 becomes the continuous part 35 of the absorber 3. FIG. The mixed fiber of the pulp fiber and the absorbent polymer formed as described above is covered with a core wrap sheet (not shown) made of paper such as tissue paper or various nonwoven fabrics to form the absorbent body 3.
Since the recessed portion absorbing portion 34 and the protruding absorbing portion 33 of the absorbent body 3 integrally formed in this way are formed without being pressed or the like, the fiber density does not increase and the absorbent body 3 has a substantially uniform density. Have. Further, the recess absorbing portion 34 has a lower basis weight than the protruding absorbing portion 33 because of its thin thickness. Unlike being formed by squeezing such as embossing, the recessed portion absorbing portion 34 has a low resistance to liquid passage, and the liquid is easily moved in the thickness direction. Moreover, since the absorber 3 integrally formed in this way does not have a part hardened by pressing, such as embossing, the touch becomes good. When the napkin 30 having the absorbent body 3 is attached, the softness of the absorbent body 3 can be realized without any hard contact with the topsheet 21, and the portion of the recess 31 is flexible so that it fits the body and is good. A feeling of wearing is obtained.

In this way, the recessed portion absorbing portion 34 suppresses the amount of liquid retained and quickly moves the liquid to the recessed portion 31, and the recessed portion 31 has a function of temporarily storing excretory liquid so that the liquid does not return to the surface sheet 21 side. The ratio (%) (see FIG. 10) of the depth (h ₂ ) of the concave portion 31 to the thickness of the absorber 3 (thickness of the protruding absorbing portion 31) (h ₁ ) (see FIG. 10) is 40% to 98%, particularly 30% to 70%. It is preferably 40% to 60%. By setting it to the above lower limit or more, liquid residue and liquid return to the topsheet can be more effectively suppressed, and by setting it to the upper limit or less, the liquid received from the topsheet is not excessively spread to the protrusion absorbing portion 33. And can be moved. For the same reason, the constituent material basis weight (w ₁ ) of the region B (see FIG. 10) having the recessed portion absorbing portion 34 and the recessed portion 31 is preferably 30 to 160 g / m ² , and 50 to 150 g / m ^2. More preferably. The basis weight (w ₂ ) of the region A (see FIG. 10) having the protruding absorbing portion 33 is preferably 180 to 400 g / m ² , and more preferably 200 to 300 g / m ² . Further, the basis weight ratio (w ₁ / w ₂ ) of both is preferably 0.1 to 0.8, and more preferably 0.3 to 0.6.

In the present invention, the concave portion 31 is a portion that is recessed from the bottom of the absorbent body 3 to the skin contact surface side to form a gap. The recessed part absorption part 34 is a part of the absorber 3 located in the upper part of the recessed part 31, Comprising: It is a part of the absorber 3 divided by the virtual lines s and s extended from the wall surface

bottom parts

31a and 31a to the thickness direction. (See FIG. 12). The protrusion absorbing portion 33 is a portion of the region A adjacent to the region B of the concave portion 31 and the concave portion absorbing portion 34 arranged in the thickness direction and from the top to the bottom of the absorber surrounded by the region B (see FIGS. 10 and 12). ).

The thickness (h ₃ ) of the recessed portion absorbing portion 34 and the thickness (h ₁ ) of the protruding absorbing portion 33 defined as described above are measured by placing an acrylic plate having a size of 37 mm × 37 mm and a thickness of 3 mm on the absorbent core 10. The thickness (h ₁ ) of the protrusion absorbing portion 33 including the upper portion 33a is measured using a non-contact type laser displacement meter (laser head LK-G30, displacement meter LK-GD500) manufactured by KEYENCE, and the thickness of the concave absorbing portion 34 ( h ₃ ) was measured by using a microscope VHX-1000 manufactured by KEYENCE to obtain a cross section corresponding to FIG. 10 of the absorber.
The method of measuring the basis weight of the recesses absorbing portion 34 basis weight of _{(w 1)} and projecting absorbing portion 33 _{(w 2)} is pressed against FEATHER Co. razor (Feather razor S single-edged), recesses absorption of the recess 34 is cut out and weighed and divided by the area of the cut out portion, and similarly, the protruding absorbent part 33 including the upper portion 33a is cut out, and the weight is measured and divided by the cut out area of the basis weight. Was calculated.

In the present embodiment, the water-absorbing polymer inside the absorber 3 exists uniformly, but in order to more effectively suppress liquid return, the water-absorbing polymer is lower than the continuous part 35 including the recessed part absorbing part 34. It is preferable that the protrusion absorbing portion 33 is arranged with a large amount of deviation, and is not arranged in the continuous portion 35 including the concave portion absorbing portion 34 but is arranged with a large amount of deviation on the non-skin surface side in the protruding absorption portion 33. More preferably. It is also preferable from the same viewpoint to dispose a water-absorbing polymer on the non-skin surface side of the recess 31.
Furthermore, in the absorbent body 3 of the present embodiment, it is preferable that the liquid passage structure having the recess 31 extends to the outer portion of the leak-proof groove 5 in the width direction. With this arrangement, the product bending rigidity with the width direction of the product as the axis is reduced, and it is easy to deform according to the wearer's body curve from the crotch to the buttocks, and on both sides of the absorbent body 3 where side leakage is likely to occur. Furthermore, flexibility can be imparted to fit the wearer's crotch, and a gap can be prevented from following the movement of the wearer's body.

Here, the characteristics of the dynamic action of the partitioned absorbent body 3 and the surface sheet 21 in the sanitary napkin 30 of the present embodiment will be described in detail with reference to FIG. FIG. 12 is a partial cross-sectional view showing an enlarged part of a predetermined cross section of the sanitary napkin shown in FIG. 9. In addition, in order to avoid complication of the figure, the back sheet 2 and the side sheet 4 are not shown, and the shape of the top sheet 21 is schematically shown. In the practice of the present invention, the shape is not necessarily the same as the illustrated shape. It doesn't have to be.

As described above, the surface sheet 21 of the present embodiment has high liquid mobility in the thickness direction of the excreted liquid due to the capillary force utilizing the density gradient as described above, and quickly transfers the liquid excreted from the body to the absorber 3. Can be migrated. Further, the protrusion 14a of the upper layer 11 and the protrusion 14b of the lower layer 12 are formed at the same position in the thickness direction (see FIG. 12), so that the liquid can easily move so as to gather in one place in a plane. Even a small amount of liquid is preferable because it is guided to the absorber 3 and is effectively transmitted to the absorber 3 side. In particular, when the fiber density is different between the upper layer 11 and the lower layer 12 and the fiber density of the lower layer is high, the liquid tends to stay on the lower layer side of the surface sheet. And improved dry feeling due to low liquid return. As described above, the absorbent body 3 has the plurality of recesses 31 on the non-skin contact surface side, and the recess absorption part 34 is disposed on the skin contact surface side. The concave portion absorbing portion 34 has a lower liquid resistance than the other absorber portions, and the liquid a ₁ excreted using this portion as a chamber is quickly absorbed in the thickness direction of the absorber 3. A part of the liquid that has moved in the thickness direction of the absorber 3 becomes the transition liquid a ₂ toward the protruding

protrusions

33 and 33 around the periphery, and the other part becomes the storage liquid a ₃ that is taken into the recess 31. . Thus, the liquid that is transmitted from the topsheet 21 is pulled by the recesses absorbing portion 34, it is distributed into a ₂ and a _3, a holding amount of reduced flow-through resistance at the surface side of the absorbent body It will be even lower. Thereby, the liquid return to the surface sheet 21 can also be suppressed effectively.
As described above, the sanitary napkin 30 according to the present embodiment has the performance of the top sheet 21 having high liquid permeability in the thickness direction, and the liquid permeability in the high thickness direction of the absorbent body 3 having the recess 31. Can be sufficiently exerted by this, thereby suppressing the return of the moisture taken in to the skin and giving the user a suitable dry feeling.

The magnitude | size and shape of the protrusion absorption part 33 and the recessed part 31 by this embodiment are not specifically limited. Although slightly different depending on the application of the absorbent article to be used, the longitudinal length k ₁ (see FIG. 11) of the protruding absorbent portion 33 is such that the absorbent body gradually curves toward the skin contact surface with the concave portion as a base axis. From the viewpoint of encouraging deformation along the shape of the wearer's body, 10 to 30 mm is preferable, and 15 to 25 mm is more preferable. The width direction length k ₂ is preferably 5 to 20 mm, more preferably 7 to 15 mm from the viewpoint of alleviating the compressive force from the width direction applied to the absorbent body while the concave portion is worn. The longitudinal length s of the recess 31 is preferably 1 to 5 mm, more preferably 1 to 3 mm. The width direction length r is preferably 1 to 5 mm, and more preferably 1 to 3 mm.

The top sheet 21 is not limited to the above-described form, and can be appropriately changed without departing from the gist of the present invention. For example, the surface sheet 21 may be composed of a fiber sheet having a three-layer structure. In this case, it is desirable that the middle layer 13 is composed of fibers having heat shrinkability, and the upper layer 11 and the lower layer 12 are composed of fibers having no heat shrinkability. From the viewpoint of increasing the liquid permeability, it is desirable that the basis weight of the upper layer 11 is larger than the basis weight of the lower layer 12.

Below, the forming material of the member which comprises the

sanitary napkin

10, 20, and 30 of this embodiment is demonstrated.
As a material for forming the top sheet 1, the back sheet 2, the absorber 3, and the side sheet 4, those employed for this type of article can be used without particular limitation. For example, as the surface sheet 1, a laminated structure of various nonwoven fabrics (for example, an air-through nonwoven fabric or a spunbond nonwoven fabric) or a composite sheet formed of a laminate of a nonwoven fabric and a film and having a large number of apertures is used. It is done. In addition, the top sheet is composed of three layers, an upper layer, a middle layer, and a lower layer, and the upper layer and the lower layer are joined to a flat middle layer as a undulating shape with a protruding portion and a portion consolidated by embossing. Good.

The side sheet 4 is preferably a water-repellent nonwoven fabric, and is water-repellent from a nonwoven fabric, spunbond nonwoven fabric, meltblown nonwoven fabric, spunlace nonwoven fabric, heat roll nonwoven fabric, needle punch nonwoven fabric, etc. manufactured by the card method. Various non-woven fabrics can be used. Particularly preferably, for example, a spunbond nonwoven fabric, a spunbond-meltblown (SM) nonwoven fabric, a spunbond-meltblown-spunbond (SMS) nonwoven fabric, or the like is used.

Although there is no restriction | limiting in particular as a constituent material of the absorber 3, A fiber material, a porous body, those combinations, etc. can be used. Examples of the fiber material include natural fibers such as wood pulp, cotton and hemp, polyolefin resins such as polyethylene and polypropylene, polyester resins such as polyethylene terephthalate, and single fibers made of synthetic resins such as polyvinyl alcohol resin, and these resins. Bisynthetic fibers containing two or more of them, and semisynthetic fibers such as acetate and rayon can be used. When using a fiber made of a synthetic fiber, the fiber may be a heat-shrinkable fiber whose shape changes due to heat. For example, the fineness is increased by heat but the fiber length is shortened, and the fineness is hardly changed by heat, but the length occupied by the apparent fiber is shortened by changing the shape to a coil shape. Also good. As the porous body, sponge, non-woven fabric, aggregate of superabsorbent polymer (aggregate of superabsorbent polymer and fiber) and the like can be used.

As the back sheet 2, a moisture permeable film alone, a non-moisture permeable film alone, a laminate of a film and a nonwoven fabric, or a water-repellent nonwoven fabric (such as SMS or SMMS) can be used. It is most preferable to use a moisture permeable film or a non-moisture permeable film alone as a leak-proof material from the viewpoint of matching with an anti-slip adhesive. As the moisture permeable film material, a film obtained by melt-kneading a thermoplastic resin and an inorganic filler that is not compatible with the thermoplastic resin and extruding the film to a predetermined dimension, or a film having essentially moisture content is used. A non-porous film having high compatibility and capable of discharging water vapor, such as an osmotic membrane, can be used. In order to realize a leak-proof layer that fully exhibits the performance of moisture discharge related to the present invention and does not exude moisture, the moisture permeability should be in the range of 0.7 to 3.0 g / 100 cm ² hr. Is more preferable, and is more preferably in the range of 1.0 to 2.5. From the standpoint of sufficiently improving the smoothness, it is most preferably from 1.5 to 2.5. In order to be usable without trouble such as film breakage, the film basis weight is 18 to 70 g / m ² , more preferably 25 to 60 g / m ² . A preferable inorganic filler content is 30 to 65% by mass, more preferably 40 to 60% by mass, based on the total mass of the film.

As described above, the absorbent article according to the present invention has the absorbent body configured as described above, so that the absorbent article is absorbed through the skin contact surface side portion of the absorbent body and the recessed absorbent part of the absorbent body and diffuses in the planar direction. While being drawn in quickly, the liquid is absorbed and held (immobilized) in the block-shaped protruding absorbing portion. In the liquid flow structure arranged in the vertical and horizontal directions of the absorbent body, since there is a concave portion absorbing portion on the skin contact surface side of the concave portion (dent), the concave portion absorbing portion is promoted to transfer rather than holding the liquid, and the liquid is quickly It is easy to be absorbed and held by the protruding absorption part. In the said recessed part, the liquid which passes a recessed part absorption part can be temporarily hold | maintained, and the liquid residue by the surface sheet side is suppressed. Since the liquid held in the concave portion is absorbed and held on the non-skin contact surface side of the protruding absorbent portion, the liquid does not easily return. In this way, the liquid can be reliably absorbed and held by each of the large number of block-like protruding absorbing portions dispersedly arranged via the liquid passing structure. In addition, as in the second embodiment, the protrusion on the back surface side of the top sheet can smoothly transfer the liquid to the absorbent body, and wet back of the liquid that has once transferred to the absorbent body to the skin side can also be prevented. In other words, the combination of the topsheet having regular protrusions and the absorbent body having a liquid passage structure composed of concave portions and concave portion absorbing portions has excellent liquid permeability in the thickness direction and enables reliable absorption and retention of liquids. .

In the present invention, the structure of the high-density region 38 and the low-density region 39 of the absorber, and the liquid passing structure including the concave portion 31 and the concave portion absorbing portion 34 are not limited to those arranged in the entire vertical direction as in the present embodiment. Instead, it may be arranged only in the excretion part corresponding region. The absorbent article of the present invention is not limited to the above embodiment, and the present invention can be applied to this type of sanitary napkin, such as an incontinence pad and an incontinence liner. Moreover, it is effective not only for menstrual blood but also urine, orimono, loose stool, and the like. In addition to the

top sheets

1 and 21, the absorber 3, the back sheet 2, and the side sheet 4, members may be appropriately incorporated in accordance with applications and functions. In addition, the material of the

top sheets

1 and 21 of the sanitary napkin of the said embodiment, the absorber 3, and the back sheet 2, conditions in a manufacturing method, and dimensional terms of a product are not specifically limited, It uses with a normal sanitary napkin etc. Various materials can be used.

Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not construed as being limited thereto.

[Example 1]
A mixture of pulp fibers and a superabsorbent polymer is sucked and deposited on an accumulation portion having protrusions arranged at equal intervals in the vertical and horizontal directions provided on the peripheral surface of the pile drum of the pile machine, and the absorber total pulp basis weight the amount 200 g / ^{m 2,} to obtain a stacks of absorber total height water-absorbing polymer basis weight 52 g / pulp fibers and superabsorbent polymer ^{m 2} (FIG. 5 (c)) (the total pulp basis weight, total height water The basis weight of the conductive polymer means the basis weight including the entire uneven portion). The absorbent body obtained by covering this piled body with a core wrap sheet, passing between a pair of press rolls and compressing with a pressure of 3.0 kgf / cm ^{2 was} designated as Sample 1 of Example 1. In this sample 1, the average density (m ₂ ) of the protruding absorption parts 33 as the high-density regions 38 is 0.12 g / cm ³ , and the average density (m ₁ ) of the recess absorption parts 34 as the low-density regions 39. Was 0.08 g / cm ³ . The average basis weight (w ₂ ) of the high density region 38 was 240 g / m ² , and the average basis weight (w ₁ ) of the low density region 39 was 100 g / m ² . In addition, the thickness (h ₃ ) of the recess absorbing portion 34 was 1.2 mm, and the thickness (h ₁ ) of the protruding absorbing portion 33 was 2.0 mm. Vertical length _{k 1} is 20mm width direction length _{k 2} of the projecting absorbing portion 33 is 10 mm, the longitudinal length s is widthwise length r is 2.0mm in the recess 31 at 1.0mm there were.
Remove the absorber from Kao Corporation's commercially available sanitary napkin (trade name “Lorrieev Many Day to Normal Day”), place the sample 1 above on the removed absorber, and restore the rest Thus, a sanitary napkin for evaluation was obtained. The surface sheet of the above-mentioned commercially available sanitary napkin is composed of a nonwoven fabric having the following configuration.
Non-woven fabric: a laminated non-woven fabric having a two-layer structure having upper and lower fiber layers, the upper layer is made of 100% core-sheath type composite fiber having polyethylene terephthalate as a core and polyethylene as a sheath, and the lower layer is a latent spiral crimpable fiber (Yamato NBF-L (V) fiber manufactured by Boeing Co., Ltd., which is a core-sheath type composite fiber having a polyethylene core and polypropylene sheath, which develops a helical crimp upon heating. The weight ratio of the upper and lower layers (upper layer / lower layer) is 50/50. The upper and lower layers are joined by dot-like embossed portions arranged in a dotted pattern, and the underlying latent crimpable fibers are in a state of being contracted by heating.

[Comparative Example 1]
The above-mentioned commercially available sanitary napkin of Kao Corporation was used as a sanitary napkin for a comparative example. In this commercially available sanitary napkin absorbent body (sample 2), circular embossed portions having a diameter of 2 mm were formed in a zigzag pattern over the entire area. The pitch between the center points of the embossed part is 7 mm. The basis weight (basis weight) was 250 g / m ² .

Further, as reference examples and comparative examples 2 to 4, the samples 3 to 6 of the absorbent body having a cross section as shown in FIGS. 13A to 13D were evaluated by applying them to the above-mentioned commercially available sanitary napkin.
[Reference example]
A mixture of pulp fibers and a water-absorbing polymer is sucked and deposited on a stacking portion having protrusions arranged at equal intervals in the vertical and horizontal directions provided on the peripheral surface of the stacking drum of the stacking machine, and the basis weight of the protruding absorbing portion A laminated fiber body of pulp fibers and a water-absorbing polymer having 240 g / m ² and a concave absorbent part 115 g / m ² was obtained (FIG. 13A). The absorbent body obtained by coating this piled body with a core wrap sheet was used as the sample of Example 1 (Sample 3). What was comprised from the pulp fiber and the superabsorbent polymer was used, and the projection part used the thing of the magnitude | size of 20 mm (longitudinal direction) x10 mm (width direction).

[Comparative Example 2]
The depth (h ₂ ) of the recess in the absorbent body of this embodiment is 30% of the absorber thickness (projection absorption part thickness), the basis weight of the projection absorption part is 240 g / m ^2, and the basis weight of the recess absorption part is Except for the amount of 160 g / m ² , the absorber was obtained in the same manner as in Example 1 including dimensions, and used as a sample (Sample 4) of Comparative Example 1 (see FIG. 13B).

[Comparative Example 3]
The absorbent body was obtained in the same manner as in Example 1 except for the dimensions except that the absorbent body was not provided with a recess and the total basis weight of the absorbent body was 200 g / m ^2, and the sample of Comparative Example 2 (Sample 5) and (See FIG. 13C).

[Comparative Example 4]
It squeezed with pin embossing from the non-skin contact surface side of the absorbent body of Comparative Example 2, and the high pressure squeezed portion 35 was formed on the skin contact surface side. Otherwise, including the dimensions, an absorbent body was obtained in the same manner as in Example 1 to obtain a sample (Sample 6) of Comparative Example 3 (see FIG. 13D).

[Performance evaluation]
<1> With respect to the above Examples, Comparative Examples 1 to 4 and Reference Example, 3 g of blood was injected into the sanitary napkin three times at intervals of 3 minutes from the surface sheet side, and evaluation was performed in an environment at 25 ° C. For the surface layer liquid return evaluation, the amount of horse blood injected was absorbed at a total of 6 g, and the diffusion area of the liquid was the area after absorption of 9 g of horse blood. As blood to be injected into the napkin, horse blood was used. More specifically, equine defibrinated blood manufactured by Japan Biotest Laboratory Co., Ltd. was used. The viscosity of this horse defibrinated blood was measured with a (B) viscometer TVB-10M manufactured by Toki Sangyo Co., Ltd. (measurement temperature 25 ° C., rotor
L adapter) and less than 15 mPa · S. The same equine blood was used in the examples and comparative examples.
<2> Method for Measuring Surface Liquid Return Amount 3 g of horse blood is injected using a liquid injection plate having an opening diameter of 10 mm in the liquid injection part. One minute after the liquid injection, a weight-measured tissue is placed on the napkin surface, and a 125 g metal plate is further placed thereon, and pressurized for 5 seconds (pressure 4.5 g / cm ² ). Measure. Further, the amount of liquid adhering to the napkin contact surface of the injection plate was also measured, and the total value of both was taken as the surface liquid return amount when 3 g of horse blood was injected. Three minutes after the first injection, 3 g of horse blood was injected again, and one minute after the injection, the same operation was repeated to obtain the amount of returned surface fluid at the time of 6 g of cumulative horse blood injection. 3 g of horse blood was injected again, and the same operation was repeated 1 minute after the injection, and the amount of the surface layer liquid returned when 9 g of total horse blood was injected was obtained.
<3> Measuring method of liquid diffusion area The liquid spreading area on the surface layer (surface sheet side) of the absorbent body of the napkin (after 6g of equine blood) used for surface layer liquid return evaluation was measured using an image analyzer and liquid diffusion The area.
The evaluation results are shown in Table 1 below.

〔Measuring method〕
Place a sanitary napkin horizontally, put an acrylic plate with a cylinder with a 1 cm diameter injection port on the bottom, and inject 3 g of defibrinated horse blood (manufactured by Nippon Biotest Co., Ltd.) from the injection port. Hold that state for a minute. Next, the acrylic plate with a cylinder was removed, and 16 sheets of absorbent paper (commercially available tissue paper) having a length of 6 cm × width of 9.5 cm and a basis weight of 13 g / m ² were placed on the surface of the surface sheet. Further, a weight was placed thereon so that the pressure was 4.0 × 10 ² Pa, and pressure was applied for 5 seconds. After pressurization, the absorbent paper was taken out, the weight of the paper before and after pressurization was measured, and the weight of defibrinated horse blood absorbed by the paper was measured to determine the remaining amount of surface liquid.

The above evaluation results are shown in Table 1 below.

As is clear from the results shown in Table 1, it is clear that the absorbent bodies of the examples have a small liquid diffusion area, little liquid return, and little wet back to the skin.

[Flexibility]
The sanitary napkins of Example 1 and Comparative Example were fixed to shorts and attached to a female human body model. When a pressure sensor ("pressure sensor element" made by PPS (Pressure Profile System)) is inserted into the buttocks of the human body model and the foot of the female human body model is bent inward, within a pressure detection range of 25mm x 25mm The maximum detected pressure was determined.
As a result, the maximum pressure applied to the model collar of the sanitary napkin of Example 1 was 0.7 kPa, and the maximum pressure applied to the model collar of the sanitary napkin of the comparative example was 1.4 kPa.
From this result, compared with the sanitary napkin of the comparative example, the sanitary napkin of Example 1 has a lower pressure applied to the wearer's buttocks when performing the operation of closing the foot at the time of wearing. It has been found that it provides a more comfortable wearing feeling with less discomfort.

[Angle prevention]
The sanitary napkins of Example 1 and Comparative Example were fixed to shorts and attached to a dynamic model of a human body. When the cross section along the width direction of the sanitary napkin after the dynamic model was allowed to walk for 30 minutes, the absorbent body of the sanitary napkin of the comparative example was bent in an M shape. On the other hand, the sanitary napkin absorbent body of the example is bent in a substantially trapezoidal shape with the central portion in the width direction being kept relatively flat, and the depression in the center in the width direction as in the comparative example is almost not. There wasn't.
From these results, it can be seen that the sanitary napkin of Example 1 has higher anti-slipping properties than the sanitary napkin of the comparative example, and is superior in terms of fit to the wearer's skin. It was.

While this invention has been described in conjunction with its embodiments, we do not intend to limit our invention in any detail of the description unless otherwise specified and are contrary to the spirit and scope of the invention as set forth in the appended claims. I think it should be interpreted widely.

This application claims priority based on Japanese Patent Application No. 2010-282455 filed in Japan on December 17, 2010, and Japanese Patent Application No. 2010-282456 filed on December 17, 2010 in Japan. Which are hereby incorporated by reference herein as part of their description.

DESCRIPTION OF SYMBOLS 1 Top sheet 2 Back sheet 3 Absorber 31 Concave part 33 Protrusion absorption part 34 Concave absorption part 4 Side sheet 5 Leak-proof groove 10 Sanitary napkin

Claims

A vertically absorbent article having a liquid-permeable surface sheet disposed on the skin contact surface side, a back sheet disposed on the non-skin contact surface side, and an absorber disposed between both sheets,
The absorbent body has a longitudinal direction and a width direction perpendicular to the longitudinal direction, and in a region corresponding to the excretion part, in the longitudinal direction and the width direction of the absorbent body, in the thickness direction from the non-skin contact surface side. A liquid-permeable structure composed of a recessed groove-shaped concave part and a concave part-absorbing part containing pulp fibers at the bottom part on the skin contact surface side of the concave part is arranged, and the region surrounded by the liquid-permeable structure is Protruding to the non-skin contact surface side, and including a pulp fiber, comprising a block-shaped protruding absorbent part having a higher basis weight than the recessed part absorbent part,
The absorbent article according to the present invention, wherein the recess-absorbing portion having the liquid-permeable structure has a low density and the block-shaped protruding absorbing portion has a relatively high density.
The average density of the constituent members of the recess absorbing portion is 0.02 to 0.09 g / cm 3 , and the average density of the constituent members of the protruding absorbing portion is 0.10 to 0.25 g / cm 3. The absorbent article as described.
The absorbent article according to claim 1 or 2, wherein a depth in the thickness direction of the groove-shaped recess of the absorbent body is 40% to 98% of a thickness of the block-shaped protruding absorbent part.
The surface sheet has a number of parts that regularly protrude on the skin contact surface side and the non-skin contact surface side, and the protrusions are at the same positions on the skin contact surface side and the non-skin contact surface side. The absorbent article according to any one of claims 1 to 3, wherein the absorbent article is disposed.
The absorbent according to any one of claims 1 to 4, wherein the absorbent body contains a water-absorbing polymer, and the water-absorbing polymer is arranged biased toward the non-skin contact surface side of the protruding absorbent portion. Goods.
The absorbent article according to claim 5, wherein a superabsorbent polymer is also disposed in the recess absorbing portion.
The absorbent article according to any one of claims 1 to 5, wherein the absorbent article is a sanitary napkin.