JP4031425B2 - Absorbent articles - Google Patents

Description

  The present invention relates to an absorbent article.

Conventionally, sanitary napkins as absorbent articles are, for example, a liquid-permeable top sheet provided on a skin contact surface in contact with a human body and an impermeable material provided on a non-skin contact surface on the side opposite to the top sheet. A liquid back sheet and an absorber provided between the top sheet and the back sheet.
In recent years, sanitary napkins tend to be thinner, and thin absorbent bodies having high absorption performance have been developed. For example, by applying a wavy machining concave and convex portions along the longitudinal direction of the sanitary napkin to the absorbent body 4 of the thin are continuous, absorbent articles with improved absorption performance by preventing side leakage of body fluids known (For example, Patent Document 1).
JP 2003-038552 A

  However, there is a problem that the body fluid stays in the concave portion formed by performing the wave processing, so that there is a stickiness when absorbing the body fluid and a comfortable wearing feeling cannot always be obtained.

  Then, the subject of this invention is providing the absorbent article which is excellent in the feeling of mounting | wearing at the time of bodily fluid absorption while having high absorption performance.

In order to solve the above-described problem, the invention according to claim 1 includes a top sheet positioned on a surface that contacts the human body, and a bag positioned on the surface that is opposite to the top sheet and contacts the underwear. In an absorbent article comprising a sheet and an absorbent body interposed between the top sheet and the back sheet,
Wherein the top sheet side of the absorbent body, and corrugated processing is given to the concave and convex portions along the longitudinal direction are continuous in the width direction,
On the surface of the concave portion and the convex portion , irregularities having a pitch of 0.85 mm or less and a depth of 0.30 mm or more smaller than the pitch of the concave portion and the convex portion are formed ,
The absorber has an SAP layer in the middle;
The depth of the unevenness is shorter than the distance from the surface to the SAP layer,
The SAP layer is provided on a surface closer to the back sheet than half of the entire thickness of the absorber .

The invention according to claim 2 is the absorbent article according to claim 1,
The absorber includes chemical fibers exposed on the surface on the topsheet side,
The unevenness is formed by restoring the chemical fiber after pressing the absorber.

The invention according to claim 3 is the absorbent article according to claim 2,
The chemical fiber is at least one of polypropylene and polyethylene.

According to the first aspect of the present invention, the surface on the top sheet side of the absorbent body is subjected to a wave-like process in which a concave portion and a convex portion along the longitudinal direction are continuous in the width direction. The surface of the surface of the absorbent body is formed with irregularities having a pitch of 0.85 mm or less and a depth of 0.30 mm or less, which is smaller than the pitch of the concave portions and the convex portions. Becomes wider, and the absorption speed of the body fluid becomes faster. Therefore, the wearing feeling at the time of body fluid absorption is excellent while having high absorption performance.
Furthermore, since the absorber has an SAP layer in the middle, the absorption capacity is further improved. Moreover, since the depth of the unevenness is shorter than the distance from the surface to the SAP layer, the SAP layer is not exposed to the top sheet side. Therefore, if the depth of the unevenness is longer than the distance from the surface of the absorber to the SAP layer, the absorbed body fluid will infiltrate the SAP layer, and the body fluid produced by the SAP particles swelling and closely contacting each other Diffusion inhibition, that is, gel blocking may occur, but because the depth of the irregularities is shorter than the distance from the surface of the absorber to the SAP layer, the diffusion of body fluid due to the SAP particles swelling and closely contacting each other, That is, gel blocking can be prevented.
Furthermore, since the SAP layer is provided on the back sheet side rather than half the thickness of the entire absorber, the depth of the unevenness can be made more than half the thickness of the entire absorber. The surface area of the surface on the top sheet side of the body is further increased, and the absorption speed can be further improved.

  According to the invention described in claim 2, it is needless to say that the same effect as that of the invention described in claim 1 can be obtained. In particular, the absorber includes a chemical fiber exposed on the surface on the top sheet side, and absorbs the same. Since the unevenness is formed by restoring the chemical fiber after the body is pressed, a special process for forming the unevenness is not required and the cost becomes low.

  According to the invention described in claim 3, it is needless to say that the same effect as that of the invention described in claim 2 can be obtained. In particular, the chemical fiber is at least one of polypropylene and polyethylene. The restoring force is strong, and the unevenness can be formed more suitably.

Hereinafter, the absorbent article as an embodiment of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a developed view of an absorbent article to which the present invention is applied, and FIG. 2 is a cross-sectional view taken along the line II-II in FIG.

A sanitary napkin (hereinafter referred to as “napkin”) 1 as an absorbent article shown in FIGS. 1 and 2 is provided on the contact surface side with a human body, and allows a body fluid such as menstrual blood or a cage to pass through quickly. A liquid top sheet 3, a liquid-impermeable back sheet 2 made of a polyethylene sheet or the like provided on the opposite side of the contact surface with the human body, and interposed between the back sheet 2 and the top sheet 3. And the absorber 4.
Around the absorbent body 4 of the napkin 1, the back sheet 2 and the top sheet 3 extending around the absorbent body 4 are bonded by an adhesive such as hot melt or heat seal so that the edge of the napkin 1 is aligned. Bonded by means.

The back sheet 2 is formed of a sheet material having at least water shielding properties such as polyethylene. In addition, it is preferable that the sheet material has moisture permeability from the viewpoint of preventing stuffiness, and as the sheet material having the water barrier property and moisture permeability, an inorganic filler is melt-kneaded in an olefin resin such as polyethylene or polypropylene. Then, after forming the sheet, a microporous sheet material obtained by stretching in a uniaxial or biaxial direction is suitably used.
In addition, one or a plurality of adhesive layers (not shown) are formed on the outer surface of the back sheet 2, and the napkin 1 can be fixed to the underwear when worn on the body.

The top sheet 3 is formed of a perforated or non-porous nonwoven fabric, a porous plastic sheet, or the like. As the raw material fibers constituting the nonwoven fabric, synthetic fibers such as polyethylene or polypropylene such as olefin, polyester and polyamide, recycled fibers such as rayon and cupra, and natural fibers such as cotton can be used. In addition, as a method for producing the nonwoven fabric, a known method can be appropriately used. For example, the nonwoven fabric is obtained by a spunlace method, a spunbond method, a thermal bond method, a melt blow method, a needle punch method, or a combination of these. Can be manufactured.
When a large number of through holes are formed in the top sheet 3, body fluids such as menstrual blood and vaginal discharge are absorbed more quickly, and the dry touch properties are excellent.

Absorbent body 4 absorbs bodily fluids, and includes a fiber layer in which various fibers such as pulp and chemical fiber are blended and mixed at a predetermined ratio, and a super absorbent polymer (SAP) that is a superabsorbent resin. The SAP layer 6 has an absorber layer 4a that is laminated in a predetermined arrangement.
And the 1st adhesive bond layer (illustration omitted) comprised by a predetermined adhesive agent is provided in the top sheet 3 side (upper surface side) of the absorber layer 4a formed by laminating the fiber layer and the SAP layer 6. In addition, a second adhesive layer (not shown) made of a predetermined adhesive is provided on the back sheet 2 side (lower surface side) of the absorber layer 4a. The first adhesive layer and the second adhesive layer are separated from each other such as fibers and superabsorbent resin so that the fibers and superabsorbent resin in the absorber layer 4a are not separated and decomposed. It is a layer for maintaining the shape of the absorber 4 (absorber layer 4a) by adhering and fixing.

  In the present embodiment, the base fiber layer 5 formed in a predetermined thickness so that each fiber in the fiber mixture in which the pulp and the chemical fiber are blended at a predetermined ratio so as to include at least the pulp is entangled, and the The SAP layer 6 formed so as to place a predetermined amount of SAP on the upper surface of the base fiber layer 5, and a fiber mixture in which pulp and chemical fibers are blended at a predetermined ratio so as to include at least pulp on the upper surface of the SAP layer 6 An absorbent layer 4a having a fiber layer 7 formed so as to be entangled with each other in the body is formed, the surface of the fiber layer 7 on the upper surface side of the absorbent layer 4a, and the absorbent layer 4a Is applied to the surface of the base fiber layer 5 on the lower surface side so as to apply a predetermined adhesive, and a first adhesive layer and a second adhesive layer are formed to form the absorbent body 4. Has been.

  That is, the absorbent body 4 includes a base fiber layer forming step of forming a base fiber layer 5 made of a fiber mixture in which pulp and chemical fibers are blended at a predetermined ratio so as to include at least pulp, and an upper surface of the base fiber layer 5. In addition, a predetermined number of SAP layers 6 including an absorbent resin (for example, SAP) and a predetermined number of fiber layers 7 including at least one of pulp and chemical fibers are laminated in a predetermined arrangement, and the absorber layer 4a is formed. A predetermined adhesive is applied to the absorber layer forming step to be formed, the surface of the fiber layer 7 that is the upper surface of the absorber layer 4a, and the surface of the base fiber layer 5 that is the lower surface of the absorber layer 4a. Are formed and manufactured by a manufacturing method including an adhesive layer forming step of forming a first adhesive layer and a second adhesive layer, respectively.

And the absorber 4 formed in this way can be set as the absorber 4 with favorable cushioning property, the softness of a twist, and moderate elasticity strength.
In addition, it is preferable that the thickness of this absorber 4 is 0.5 mm or more and 5.0 mm or less, More preferably, it is 0.7 mm or more and 2.0 mm or less.
When the thickness of the absorbent body 4 is less than 0.5 mm, the amount of body fluid absorbed by the absorbent body is small and the absorbability of the body fluid is low, so that backflow or leakage of the body fluid may occur. Moreover, since the absorber is thin as the thickness of the absorber 4 is less than 0.5 mm, the cushion performance may be reduced and the softness may be impaired.
In addition, if the thickness of the absorbent body 4 exceeds 5.0 mm, the thickness of the napkin 1 provided with the absorbent body increases, and the napkin becomes bulky, which causes a problem that it is difficult to carry the individually packaged napkin. There is.

Here, the pulp is a material obtained by mechanically and chemically treating wood and other plant bodies to separate cellulose fibers and suspend them in water or into a cardboard form. Cellulose and hemicellulose, lignin Are the three major components, and also contain resins, pigments, and neutral substances. The types of pulp can be broadly classified according to raw materials: softwood pulp (N wood, pine, etc.), hardwood pulp (L wood, beech, etc.), non-wood pulp (kenaf, bagasse, cotton, etc.), deinked waste paper pulp (DIP) and so on. Furthermore, there are mechanical pulps that are classified according to the pulp production method and mechanically crushed and chemical pulps that are produced using chemicals such as sulfurous acid and sulfate. As special pulps, there are TCF (Total Chlorine Free) pulp, ECF (Elemental Chlorine Free) pulp, and the like.
Since the pulp is originally hydrophilic and porous, it is rich in water absorption, and there are many types of pulp depending on the combination of raw materials and production methods. Therefore, it is desirable to select and use an appropriate pulp.

Chemical fiber is a fiber made by chemically synthesizing raw materials such as coal and petroleum, or by chemically processing natural fibers. As the chemical fibers, for example, polyamide fibers such as nylon and aramid, polyester fibers such as PET fibers and PTT fibers, chemical fibers such as acrylic fibers, polyolefin fibers, and polypropylene fibers can be appropriately used. In addition, a synthetic fiber having a core-sheath structure made of polyethylene on the outside and polypropylene on the inside can be used. In addition, a synthetic fiber such as Intac (trade name), which is a synthetic fiber hydrophilized, SWP (Synthetic Wood Pulp) may be used.
By adding not only pulp but also chemical fibers to the absorbent body 4 (absorber layer 4a), the binding force between fibers in the absorbent body is increased, so that it has high resistance to external forces accompanying the movement of the wearer. In addition, due to the presence of the chemical fiber, the chemical fiber dissolves when heated, thereby serving as an adhesive. It is known that chemical fibers, for example, polypropylene dissolves at 150 ° C. or higher, and dissolves at around 400 ° C. even if the melting temperature is high. Due to the characteristics of this chemical fiber, it can be fused by heat sealing or the like without using an adhesive such as hot melt, which is gentle to the human body and can reduce the cause of rash.
Further, by adding chemical fiber to the absorbent body 4, it becomes possible to improve the cushioning property in the thickness direction of the absorbent body 4, and to balance both the absorbent property by pulp and SAP and the cushioning property by chemical fiber. The performance can be improved.

  The adhesive is for adhering each fiber such as pulp or chemical fiber or a highly water-absorbent resin on the surface of the absorber 4 and maintaining the shape of the absorber 4 (absorber layer 4a). . Examples of the adhesive include ethylene vinyl acetate copolymer resin (EVA), polyvinyl alcohol (PVA), acrylamide / polyvinyl alcohol copolymer, acrylic ester / vinyl acetate copolymer, sodium carboxymethyl cellulose, SIS, SBS, SIBS. Styrene elastomers such as SEPS, polyester / acrylic elastomers, polyolefin elastomers and the like can be used as appropriate.

SAP has a function of gelling and confining absorbed moisture by binding water molecules between molecules of its own three-dimensional network structure. Specifically, SAP is, for example, starch-polyacrylonitrile hydrolyzate, starch-polyacrylate cross-linked product, carboxyl methyl cellulose, saponified vinyl acetate-methyl acrylate copolymer, polyacrylic acid soda cross-linked product, etc. Can be used.
Usually, the absorption capacity of cotton, pulp, sponge, etc. due to “capillary phenomenon” is about 20 times its own weight, whereas SAP can absorb several hundred to 1000 times its own weight. In the SAP, water molecules are held in a form that is tightly held down by hydrogen bonds in a fine mesh of polymer stretched vertically and horizontally. Since water molecules are bound inside the SAP, even if pressure is applied by actions such as squeezing or pushing, the SAP does not spout water.

  Next, the fine structure of the surface of the absorber 4 that is a feature of the present invention will be described with reference to FIGS. FIG. 3 is an enlarged cross-sectional view of the surface of the absorber 4 in FIG.

As shown in FIG. 2, the surface of the absorbent body 4 on the side of the top sheet 3 is subjected to undulating processing in which a concave portion 41 and a convex portion 42 along the longitudinal direction of the napkin 1 are continuous. The pitch A1 of the convex portion 41 and the concave portion 42 by this wave processing is 10 mm or less, the depth B1 of the concave portion 42 is 0.4 mm or more, and preferably the pitch A1 is 5 mm or less and the depth B1 is 0. .6 mm or more. This undulating process is performed by a well-known means, and has the effect of blocking the side leakage of body fluid.

  And as shown in FIG. 3, the unevenness | corrugation 43 is formed in the surface of the recessed part 41 and the convex part 42. As shown in FIG. The unevenness 43 is formed so that the pitch A2 is 0.85 mm or less and the depth B2 is 0.30 mm or more. That is, it is smaller than the pitch A1 of the concave portion 41 and the convex portion 42 by the wave processing.

Thus, by further forming the unevenness | corrugation 43 in the surface of the recessed part 41 and the convex part 42, the contact area with the inflowing bodily fluid can be enlarged, and the water absorption speed can be made quick.
If the pitch A2 of the unevenness 43 is 0.85 mm or more, or the depth B2 of the unevenness 43 is 0.30 mm or less, the surface area in contact with the body fluid does not increase, and there is a possibility that it does not contribute to the improvement of the water absorption speed. Because there is. The pitch A2 is preferably 0.50 mm or less and the depth is 1.0 mm or more.

  In addition, the depth B <b> 2 of the unevenness 43 is preferably shorter than the distance from the surface of the absorber 4 to the SAP layer 6. If the distance from the surface of the absorbent body 4 to the SAP layer 6 is longer, the absorbed body fluid will infiltrate the SAP layer 6, and the diffusion of the body fluid due to the swelling of the SAP particles and adhesion to each other, that is, This is because gel blocking may occur. In view of preventing this gel blocking, as shown in FIG. 2, it is preferable to provide the SAP layer 6 on the surface closer to the back sheet 2 than half the thickness H of the entire absorbent body 4.

The unevenness 43 is formed by unevenness processing when the absorber 4 is manufactured. Here, an example of uneven processing will be described.
In the process of manufacturing the absorbent body 4 used for the napkin 1, chemical fibers having a high restoring force such as polypropylene and polyethylene are included in the fiber layer 7 so as to be exposed on the surface on the top sheet 3 side. Thereafter, in order to reduce the thickness H of the absorbent body 4, the unevenness 43 is formed by selectively restoring the included chemical fibers when pressing is performed.

  In particular, when chemical fibers having high restoring force are included in the fiber layer 7, a portion rich in pulp and a portion rich in the chemical fibers are arranged, and both portions are exposed on the surface on the top sheet 3 side. Since only the portion rich in the chemical fiber is restored after the press working, the unevenness 43 can be formed remarkably.

  Moreover, it is also possible to form the unevenness | corrugation 43 in the absorber 4 surface, for example by embossing using the embossing roll which has a processus | protrusion of predetermined magnitude | size, without using especially a chemical fiber with high restoring force. .

  In the napkin 1 according to the present invention described above, the unevenness 43 having a pitch of 0.85 mm or less and a depth of 0.30 mm or more is formed on the surface of the absorbent body 4 on the top sheet 3 side. Thus, the surface area of the surface of the top sheet 3 on the side 4 is increased, and the absorption speed of the body fluid is increased. Therefore, the wearing feeling at the time of body fluid absorption is excellent while having high absorption performance.

  In addition, the absorbent body 4 includes chemical fibers exposed on the surface on the top sheet 3 side, and the unevenness 43 is formed by restoring the chemical fibers after the absorbent body 4 is pressed. This process is not necessary and is inexpensive.

In addition, since the absorbent body 4 is subjected to a wave-like process in which the concave portions 41 and the convex portions 42 along the longitudinal direction are continuous, the surface area of the surface of the absorbent body 4 on the top sheet 3 side is further increased, Absorption speed can be further improved.

(Modification)
FIG. 4 is an enlarged cross-sectional view showing a modification of the absorbent body of FIG. As shown in FIG. 4, the structure is the same as that of the absorbent body 4 shown in FIG. 2 except that the concave portion 44 and the convex portion 45 are formed on the surface of the absorbent body 4 on the top sheet 3 side. Are denoted by the same reference numerals, and detailed description thereof is omitted.

The depth B3 of the concave portion 44 and the convex portion 45 is formed deeper than the depth B1 of the concave portion 41 and the convex portion 42 shown in FIG. The concave portion 44 and the convex portion 45 are formed, for example, by embossing the surface of the absorber 4.
In this modification as well, irregularities 43 are formed on the surfaces of the concave portions 44 and the convex portions 45, which contributes to a larger body fluid contact area.
Further, as shown in FIG. 4, the SAP layer 6 is preferably provided on the surface on the back sheet 2 side than half of the thickness H of the entire absorbent body 4.

  In the modified example described above, the surface area in contact with the inflowing body fluid increases and the contact area with the human body decreases, so that the absorption speed of the body fluid is improved and the uncomfortable feeling at the time of wearing is further reduced. be able to.

  The absorber 4 may be manufactured without providing the SAP layer 6. In this case, by embossing using an embossing roll capable of forming a through hole in the absorbent body 4, a plurality of through holes are formed in the absorbent body 4 to increase the contact area with the inflowing body fluid. It is good also as a structure.

In the above embodiment, the absorbent layer 4a has been described with an example of a total of three layers of two fiber layers and one SAP layer, but the present invention is not limited to this. The number of the fiber layers 7 and the SAP layers 6 may be any number, and the arrangement order and the configuration of each layer (for example, types and ratios of fibers and resins) are arbitrary.
In addition, it is needless to say that other specific detailed structures can be appropriately changed.

Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples, but the present invention is not limited to these examples.
As shown in Table 1, the absorber is configured by stacking the first to fifth layers. Here, three layers from the second layer to the fourth layer correspond to the absorber layer.
In addition, the compounding ratio of each layer and the constituent material in each layer is indicated by the basis weight (g / m ² ).
Table 2 shows the processing applied to each example and comparative example.

As shown in Tables 1 and 2, forming the second layer is a base fiber layer as pulp 45 g / m ^2, polypropylene / polyethylene (3.3 / 5.0) is the blending ratio of 3 g / m ² Then, a third layer which is an SAP layer is formed on the second layer so that the SAP is 50 g / m ^2, and the pulp is 45 g / m ² on the third layer, polypropylene / polyethylene (3.3 / The fourth layer, which is a fiber layer, was formed so that 5.0) had a blending ratio of 3 g / m ² , and an absorber layer was manufactured.

Next, EVA as an adhesive is spray-applied to the upper surface side and the lower surface side of the absorber layer, respectively, and a fifth layer which is the first adhesive layer so as to be 3 g / m ² , respectively. A first layer which is a second adhesive layer was formed to manufacture an absorbent body.

Next, press working for thinning the absorber was performed, and irregularities were formed on the surface of the absorber. The unevenness formed was such that the pitch was 0.85 mm and the depth was 0.30 mm, and the ratio of the recesses to the surface was 15%.
Next, a napkin was manufactured so that the absorbent body was interposed between the top sheet and the back sheet.
Tables 3 and 4 show the quality evaluation results of this napkin.

As shown in Tables 1 and 2, the surface of the absorbent body obtained in Example 1 was corrugated so that concave portions and convex portions along the longitudinal direction of the napkin were continuous. The recesses and protrusions were processed so that the pitch was 2.0 mm and the depth was 0.1 mm, and the ratio of the recesses to the surface was 5%.
An absorbent body was obtained in the same manner as in Example 1 except that corrugated processing was performed, and a napkin was produced.
Tables 3 and 4 show the quality evaluation results of this napkin.

As shown in Tables 1 and 2, in Example 2, the second layer pulp was 60 g / m ² , the polypropylene / polyethylene (3.3 / 5.0) was 5 g / m ² , and the fourth layer pulp. Was replaced with 30 g / m ² , and a napkin was produced in the same manner as in Example 2 except that the depth of the unevenness by the uneven processing was 0.5 mm.
Tables 3 and 4 show the quality evaluation results of this napkin.

As shown in Tables 1 and 2, embossing is performed on the surface of the absorbent body obtained in Example 1 in order to continuously form recesses and protrusions deeper than the recesses and protrusions by corrugation. gave. In this embossing, the recesses and the protrusions were processed so that the pitch was 0.5 mm and the depth was 0.8 mm, and the ratio of the recesses to the surface was 20%. Except for embossing, an absorbent body was obtained in the same manner as in Example 1 to produce a napkin.
Tables 3 and 4 show the quality evaluation results of this napkin.

As shown in Tables 1 and 2, the absorbent body obtained in Example 3 was embossed in the same manner as in Example 4 so that the depth of the unevenness was 1.0 mm, and the ratio of the recesses in the surface The absorbent was obtained in the same manner as in Example 3 except that the content was changed to 20%, and a napkin was produced.
Tables 3 and 4 show the quality evaluation results of this napkin.

[Comparative Example 1]
As shown in Tables 1 and 2, in Example 1, the second and fourth layers of polypropylene / polyethylene (3.3 / 5.0) were not added, and the first layer and the fifth layer were formed. Without carrying out this, it was carried out except that 16 g / m ² of crepe paper was arranged in the arrangement corresponding to the first layer to produce an absorbent body, and the surface of the absorbent body 4 became substantially flat after pressing. A napkin was produced as in Example 1.
Tables 3 and 4 show the quality evaluation results of this napkin.

[Comparative Example 2]
As shown in Tables 1 and 2, the absorber obtained in Comparative Example 1, except that subjected to corrugated processing as concave and convex portions along the longitudinal direction of the napkin is continuous in the same manner as in Comparative Example 1 An absorbent body was obtained to produce a napkin.
Tables 3 and 4 show the quality evaluation results of this napkin.

(Absorption speed)
2 cc of artificial blood was injected from above the cylinder (height 100 mm, diameter 25 mm), and the time until the napkin completely absorbed the artificial blood was measured. This was the first measurement. Further, 3 minutes after the first artificial blood was injected, 2 cc of artificial blood was additionally injected, and the absorption time was measured in the same manner. This was the second measurement.
(Diffusion area)
One minute after injecting the artificial blood into the napkin, the diffusion area of the artificial blood was measured. This was the first measurement. First, the length in the longitudinal direction and the length in the width direction of the diffused artificial blood are measured, and then diffused using the formula of length in the longitudinal direction / 2 × length in the width direction / 2 × circumference ratio. The area was calculated. Further, 3 minutes after the first artificial blood was injected, 2 cc of artificial blood was additionally injected, and the diffusion area of the artificial blood was measured 1 minute later. This was the second measurement.
(Absorber thickness)
The thickness of the absorber measured the thickness of the absorber after press work.
(A feeling of wearing)
Changing the absorber of a commercially available napkin (trademark: Ellis Extra Slim 20cm without wings) and using the napkin in each of the above examples for 20 females in their 20s and 30s for 2 hours during menstruation The evaluation was taken. This wearing feeling was evaluated in five levels: Level 5: Very comfortable, Level 4: Comfortable, Level 3: Neither can be said, Level 2: Slightly uncomfortable, Level 1: Uncomfortable.

  Below, based on Table 3 and Table 4, the evaluation result of the napkin in Examples 1-5 is demonstrated.

(About the evaluation result of Example 1)
The napkin in Example 1 is obtained by subjecting the absorber surface to a concavo-convex process with a pitch of 0.8 mm and a depth of 0.3 mm.
As is apparent from Table 3, it can be seen that the napkin in Example 1 has a water absorption speed at least twice as fast as that of a napkin (Comparative Example 1) having an absorbent body with a flat surface.
The reason for this is that pulp and polypropylene / polyethylene (PP / PE) were blended in the second layer and the fourth layer of the napkin absorber in Example 1, so that the surface was uneven as PP / PE restored after pressing. This is because the surface area in contact with the body fluid increases and the body fluid is quickly absorbed.
Moreover, it turns out that the water absorption speed of the 1st time of the napkin in Example 1 is about 1.5 times faster than a napkin (comparative example 2) provided with the absorber whose surface was corrugated.
The reason for this is that the uneven pitch formed on the surface of the napkin absorber in Example 1 is 1 mm or more smaller than the pitch of the concave and convex portions formed by undulating processing on the absorbent surface of the napkin in Comparative Example 2. Moreover, since it is 0.2 mm deep, the surface area in contact with the body fluid becomes larger, and the body fluid is absorbed quickly.
This can also be seen from the fact that the first diffusion of body fluid is reduced by about 30% as compared with Comparative Examples 1 and 2.
Furthermore, as compared with Comparative Examples 1 and 2, not only the first water absorption speed but also the second water absorption speed are increased. More specifically, since it is about 1.5 times faster than Comparative Example 1 and about 1.3 times faster than Comparative Example 2, it can be seen that the water absorption performance is remarkably improved. .
Also, from Table 4, it can be seen that the comfort is improved about twice as compared with Comparative Example 1 and about 1.5 times compared with Comparative Example 2 from the average level.
Thus, it can be said that the napkin in Example 1 is a napkin with a good body fluid water-absorbing performance as compared with a conventional napkin. In addition, since the water absorption speed is high, the time during which the body fluid stays in the absorbent body is extremely shortened. Therefore, it can be said that the napkin reduces uncomfortable feeling and uncomfortable feeling when the napkin is worn.

(About the evaluation result of Example 2)
Napkin in Example 2, were subjected to corrugated processing along the longitudinal direction of the napkin on the absorber surface of Example 1.
As is apparent from Table 3, the napkin in Example 2 has a higher water absorption performance than Comparative Examples 1 and 2. This can be seen from the fact that the water absorption speed is increased as compared with Comparative Examples 1 and 2, and the diffusion of body fluid is also reduced.
The reason for this is that the corrugated absorbent body is further corrugated to form concave and convex portions on the surface of the absorbent body, and the surface area in contact with the body fluid is larger than the napkin absorbent body in Example 1. This is because the body fluid is quickly absorbed.
In particular, the second water absorption speed is about twice as fast as that of Comparative Example 1 and about 1.7 times faster than that of Comparative Example 2, and the water absorption performance is remarkably improved.
Furthermore, although the total weight of each layer constituting the absorber is 7 g / m ² smaller than that of Comparative Examples 1 and 2, the thickness of the absorber is smaller than that of Comparative Examples 1 and 2. Since it is increased by 0.2 mm, it can be seen that the cushioning property is also improved.
Also, from Table 4, the comfort level is about 2.3 times that of Comparative Example 1 and about 1.7 times that of Comparative Example 2, compared to the average level. I understand.
Thus, it can be said that the napkin in Example 2 is a napkin that has a good water absorption performance and is rich in cushioning properties and can provide a comfortable wearing feeling.

(About the evaluation result of Example 3)
The napkin in Example 3 increased the pulp amount of the second layer and the PP / PE amount of the absorbent body of Example 2, and decreased the pulp amount of the fourth layer to make the unevenness depth 0.5 mm. It is.
As is apparent from Table 3, the napkin in Example 3 has increased water absorption performance as compared with Comparative Examples 1 and 2. This can be seen from the fact that the water absorption speed is increased as compared with Comparative Examples 1 and 2, and the diffusion of body fluid is also reduced.
The reason for this is that by increasing the amount of pulp and PP / PE in the second layer of the absorber, the amount of PP / PE restored during the unevenness processing is increased and formed on the surface of the absorber 4. This is because the depth of the unevenness increases, so that the surface area in contact with the body fluid increases and the body fluid is quickly absorbed.
In particular, the second water absorption speed is about 3.4 times faster than Comparative Example 1 and about three times faster than Comparative Example 2, and the water absorption performance is significantly improved. This can be seen from the fact that the feeling of wearing is very good.
Furthermore, although the total basis weight of each layer constituting the absorber is 5 g / m ² smaller than that of Comparative Examples 1 and 2, the thickness of the absorber is smaller than that of Comparative Examples 1 and 2. Since the thickness is 0.2 mm, it can be seen that the cushioning property is also improved.
Also, from Table 4, the comfort level is about 2.6 times that of Comparative Example 1 and about 1.9 times that of Comparative Example 2, compared to the average level. I understand.
Thus, it can be said that the napkin in Example 3 is a napkin that has a better water absorption performance and a higher cushioning property than the conventional napkin, and can provide a comfortable wearing feeling.

(About the evaluation result of Example 4)
The napkin in Example 4 is obtained by embossing the absorbent body so that the uneven pitch is 0.5 mm and the depth is 0.8 mm, and is further subjected to wave processing.
As is apparent from Table 3, the napkin in Example 4 has increased water absorption performance as compared with Comparative Examples 1 and 2. This can be seen from the fact that the water absorption speed is increased as compared with Comparative Examples 1 and 2, and the diffusion of body fluid is also reduced.
The reason for this is that by embossing the rugged absorbent body, the depth of the concave and convex portions formed on the surface of the absorbent body becomes deeper, so that the surface area in contact with the body fluid increases and the body fluid quickly It is because it is absorbed in.
In particular, the second water absorption speed is about 3.6 times that of Comparative Example 1 and about three times that of Comparative Example 2, and the water absorption performance is remarkably improved. This can be seen from the fact that the feeling of wearing is very good.
Furthermore, although the total weight of each layer constituting the absorber is 7 g / m ² smaller than that of Comparative Examples 1 and 2, the thickness of the absorber is smaller than that of Comparative Examples 1 and 2. Since the thickness is 0.3 mm, it can be seen that the cushioning property is also improved.
Also, from Table 4, it can be seen that the comfort is improved about 2.8 times compared to Comparative Example 1 and about twice compared to Comparative Example 2 from the average level.
Thus, it can be said that the napkin in Example 4 is a napkin that has a good water absorption performance and a high cushioning property compared to conventional napkins and can provide a comfortable wearing feeling.

(About the evaluation result of Example 5)
The napkin in Example 5 increases the pulp amount and PP / PE amount of the second layer of the absorbent body, reduces the pulp amount of the fourth layer, and embosses the absorbent body to reduce the uneven pitch to 0. .5 mm, depth is 0.8 mm, and wave processing is further applied.
As is clear from Table 3, the water absorption performance of the napkin in Example 5 is increased as compared with Comparative Examples 1 and 2. This can be seen from the fact that the water absorption speed is increased as compared with Comparative Examples 1 and 2, and the diffusion of body fluid is also reduced.
The reason for this is that by increasing the amount of pulp and PP / PE in the second layer, the amount of chemical fibers restored during uneven processing increases, and the depth of unevenness formed on the absorber surface. By embossing the absorber, the depth of the concave and convex portions formed on the surface of the absorber becomes deeper, so that the surface area in contact with the body fluid increases and the body fluid is absorbed quickly. It is to be done.
In particular, the second water absorption speed is about 5.7 times faster than Comparative Example 1 and about 4.8 times faster than Comparative Example 2, and the water absorption performance is significantly improved. This can be seen from the fact that the feeling of wearing is very good.
Furthermore, although the total basis weight of each layer constituting the absorber is 5 g / m ² smaller than that of Comparative Examples 1 and 2, the thickness of the absorber is smaller than that of Comparative Examples 1 and 2. Since it is increased by 0.2 mm, it can be seen that the cushioning property is also improved. Since the thickness of an absorber is 0.2 mm thick compared with the comparative examples 1 and 2, it turns out that cushioning properties are also improving.
Also, from Table 4, the comfort is about 2.9 times better than Comparative Example 1 and about 2.1 times more comfortable than Comparative Example 2 than the average level. I understand.
Thus, it can be said that the napkin in Example 5 is a napkin that has a good water absorption performance and a high cushioning property as compared with a conventional napkin and can provide a comfortable wearing feeling.

As described above, the napkin according to the present invention has a good water absorption performance as compared with the conventional napkin, so that the time during which the body fluid stays on the surface of the absorbent body can be extremely shortened. Discomfort can be further reduced.
Moreover, since the napkin concerning this invention is excellent in cushioning properties, it can function suitably as a napkin with a good wearing feeling.

It is an expanded view of the absorbent article to which this invention is applied. It is sectional drawing in the II-II line of FIG. It is an expanded sectional view of the absorber surface of FIG. It is an expanded sectional view which shows the modification of the absorber surface structure of FIG.

Explanation of symbols

1 Napkin (absorbent article)
2 Back sheet 3 Top sheet 4 Absorber 6 SAP layer 7 Fiber layer 41 Concave part 42 Convex part A2 Pitch B2 Depth H Thickness

Claims (3)

A top sheet positioned on a surface that contacts the human body, a back sheet positioned on a surface opposite to the top sheet and in contact with underwear, and interposed between the top sheet and the back sheet. An absorbent article comprising:
Wherein the top sheet side of the absorbent body, and corrugated processing is given to the concave and convex portions along the longitudinal direction are continuous in the width direction,
On the surface of the concave portion and the convex portion , irregularities having a pitch of 0.85 mm or less and a depth of 0.30 mm or more smaller than the pitch of the concave portion and the convex portion are formed ,
The absorber has an SAP layer in the middle;
The depth of the unevenness is shorter than the distance from the surface to the SAP layer,
The said SAP layer is provided in the surface by the side of the said back sheet rather than half of the thickness of the whole absorber, The absorbent article characterized by the above-mentioned . The absorber includes chemical fibers exposed on the surface on the topsheet side,
The absorbent article according to claim 1, wherein the unevenness is formed by restoration of the chemical fiber after pressing the absorbent body.   The absorbent article according to claim 2, wherein the chemical fiber is at least one of polypropylene and polyethylene.

Images