JPH09276391A - Absorptive product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent an absorptivity disturbing phenomenon and to improve re-absorptivity, by composing an absorptive body by a fiber substrate so that the content of a high water absorptive resin with specific values of the absorption quantity and the passing time of physiologic saline is to be a specific wt.%. SOLUTION: For instance, an absorptive body used for a surface material 2 of a disposable diaper is formed by main constituting elements of a fibrous substrate of cellulose based fiber and a high water absorptive resin not less than 45wt.% of the total weight of the absorptive body 4. The high water absorptive resin must have absorption quantity of physiologic saline not less than 25g/g. When 0.5g of the high water absorptive resin is filled in a cylinder with the cross section area of 4:49cm<2> (inner diameter 25mmϕ), swelled up to the saturation state, and then 50ml of physiologic saline is passed through, the passing time is not higher than 20sec, for instance, such polysodiumacrylate, etc., can be used. The absorptive body is put between a surface material 2 and a back material 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an absorbent article, and more specifically, a liquid-permeable top sheet, a liquid-impermeable back sheet, and a liquid-retaining property interposed between these sheets. And an absorbent article such as a disposable diaper or a sanitary napkin.

[0002]

2. Description of the Related Art Absorbent articles such as disposable diapers, sanitary napkins and incontinence pads are absorbent bodies mainly arranged in the center thereof for absorbing and retaining body fluids such as urine and menstrual blood excreted from the body. And a flexible liquid-permeable topsheet arranged on the side in contact with the body, and a liquid-impermeable backsheet arranged on the side opposite to the side in contact with the body.

Conventionally, the above-mentioned absorber is composed of a hydrophilic fibrous base material such as wood pulp and a super absorbent polymer. The body fluid passes through the surface sheet made of non-woven fabric or the like and is absorbed by the absorber. The absorbed body fluid is temporarily stocked with a fibrous base material such as the above wood pulp,
It is transferred to and retained by the above super absorbent polymer. In a conventional absorbent article, the amount of the super absorbent polymer used is about 10 to 30% by weight of the total weight of the absorbent body.

[0004]

Generally, in order to reduce the thickness of absorbent articles, it is possible to reduce the amount of the fibrous base material used in the absorbent body and increase the amount of the superabsorbent polymer used. Conceivable. In this case, since the ratio of the superabsorbent polymer in the absorbent body increases, when the superabsorbent polymer absorbs body fluid and swells and softens, the superabsorbent polymers contact each other, or When the superabsorbent polymers come into close contact with each other due to their rearrangement or the like, the voids between the swollen superabsorbent polymers are reduced. As a result, the void as a passage for bodily fluid is closed, and a layer of bodily fluid is formed in the closed portion.
A gel blocking phenomenon will occur. In the absorbent article in which the gel blocking phenomenon has occurred, it becomes impossible to absorb the body fluid again even if the absorption amount of the body fluid has not reached the saturated state.

Therefore, the object of the present invention is to provide a thin absorbent having excellent reabsorbability without causing a phenomenon such as a gel blocking phenomenon that inhibits the absorption performance, despite the high ratio of the super absorbent polymer in the absorbent body. To provide a sex article.

[0006]

Means for Solving the Problems As a result of intensive investigations by the present inventors, the superabsorbent polymer was used in a specific ratio in an absorber, and the superabsorbent polymer had a specific water absorption amount and liquid passage time. It was found that an absorbent article that can achieve the above object can be obtained by using a material having

The present invention has been made on the basis of the above findings, and is an absorbent having a liquid-permeable top sheet, a liquid-impermeable back sheet, and a liquid-retaining absorber interposed between these two sheets. By providing an absorbent article, wherein the absorbent body satisfies the following conditions 1), and the superabsorbent polymer contained in the absorbent body satisfies the following conditions 2) and 3): The above-mentioned object is achieved. . 1) The absorbent body mainly comprises a fibrous base material and a super absorbent polymer, and 45% by weight of the total weight of the absorbent body.
The above is the super absorbent polymer. 2) The amount of physiological saline solution absorbed by the centrifugal dehydration method of the superabsorbent polymer is 25 g / g or more. 3) Cross-sectional area 4.91c of 0.5 g of the super absorbent polymer
A cylinder of m ² (inner diameter 25 mmφ) was filled with physiological saline, and the superabsorbent polymer was swollen with the physiological saline until it reached a saturated state, and 50 ml of physiological saline was added after the swollen superabsorbent polymer was precipitated. The liquid passage time (hereinafter, referred to as “liquid passage time” when measured under these conditions) when passing through is 20 seconds or less.

The present invention also provides the absorbent article, wherein the water absorption is 35 to 65 g / g.

In the absorbent article of the present invention, the absorbent body is composed of two or more layers, and at least 1
One layer is a layer made of the fibrous base material, and at least one other layer is a layer made of the superabsorbent polymer or a mixture of the superabsorbent polymer and the fibrous base material. , An absorbent article in which these layers are alternately laminated is provided.

In the absorbent article of the present invention, the absorbent body is composed of three layers, and the three layers are composed of the superabsorbent polymer or the superabsorbent polymer and the fibrous base. It is intended to provide an absorbent article in which a layer made of a mixture with a material is sandwiched and laminated between two layers made of the same or different fibrous base materials.

Further, the present invention provides the absorbent article, wherein the sum of saturated water absorption by the physiological saline of the layer made of the fibrous base material is 0.1 g / cm ² or more. Is.

The present invention also provides the absorbent article, wherein at least one of the layers made of the fibrous base material is a sheet-shaped layer made of hydrophilic fibers. It is a thing.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a preferred embodiment of an absorbent article of the present invention will be described with reference to the drawings, taking a disposable diaper as an example. Here, FIG. 1 is a perspective view showing a disposable diaper as a first embodiment of an absorbent article of the present invention, and FIG. 2 is a partially broken plane showing a state in which the disposable diaper shown in FIG. 1 is expanded. It is a figure.

The disposable diaper 1 of the embodiment shown in FIGS. 1 and 2 is interposed between a liquid-permeable surface material 2, a liquid-impermeable back material 3, and the surface material 2 and the back material 3. The liquid absorbent absorbent body 4 is provided, and an abdominal waist portion 5 located on the abdominal side of the wearer and a back waist portion 5 ′ located on the dorsal side are formed when worn.

[0015] The back waist portion 5'of the disposable diaper 1 is fastened to both sides in the width direction of the back waist portion 5'when the wearable disposable diaper 1 is worn. A pair of fastening tapes 10 and 10 '
Are arranged. On the surface of the back material 3 at the abdominal waist portion 5 of the disposable diaper 1, a landing tape 11 as a fastening portion of the fastening tapes 10 and 10 'is provided. , 10 ′ is the landing tape 11
Is configured to be fastened to.

The absorber 4 has a portion corresponding to the crotch portion of the diaper, which is entangled, and is curved in an hourglass shape.
In addition, an abdominal waist portion 5 located around the absorber 4
In the back waist portion 5 'and the left and right leg portions, the waist elastic member 6 and the leg elastic member 8 are fixed between the front surface member 2 and the back surface member 3 in an extended state, respectively. . Then, the waist elastic member 6 and the leg elastic member 8 contract in a free state, and as shown in FIG. 1, the waist gathers 7 and 7'and the leg gathers 9 are respectively in the waist portion and the crotch of the wearer. , 9 ′ are formed to fit the waist and the crotch.

Each member constituting the disposable diaper 1 will be described. The surface sheet 2 is a liquid permeable sheet that allows excrement to permeate into the absorbent body 4,
Those having a feeling close to underwear are preferred. As such a liquid permeable sheet, for example, a woven fabric, a nonwoven fabric, a porous film and the like are preferably mentioned. Further, a method of applying a hydrophobic compound such as a silicone oil or paraffin wax to the peripheral edge of the surface sheet 2, or a method of applying a hydrophilic compound such as an alkyl phosphate ester in advance to the entire surface and washing the peripheral edge with warm water. It is also preferable to use a water-repellent treatment on the peripheral edge of the surface sheet 2 by the above method to prevent the peripheral edge portion from leaking due to bleeding of urine or the like.

The back material 3 is preferably a liquid-impermeable sheet that is impermeable to liquid but permeable to vapor and has a moisture-permeable property, and has a feel close to that of underwear. Such a liquid impermeable sheet is obtained, for example, by adding a filler to a thermoplastic resin and stretching the same. In particular, as such a liquid impermeable sheet, a porous film having moisture permeability, a composite material of the porous film and a nonwoven fabric, or the like can be preferably used.

As the waist elastic members 6 for the waist gathers 7 and 7'and the leg elastic members 8 for the leg gathers 9 and 9 ', thread rubber, flat rubber, film type rubber or film-like foam. Polyurethane or the like is preferably used.

The absorbent body 4 satisfies the above condition 1), that is, it comprises a fibrous base material and a superabsorbent polymer as main components, and the total weight of the absorbent body is 45.
Use is made of a polymer having the above-mentioned superabsorbent polymer in a weight percentage of at least.

Examples of the fibrous base material include cellulosic fibers, modified cellulosic fibers, synthetic fibers, and mixtures of two or more thereof. As the cellulosic fiber, for example, natural fibers such as wood pulp and cotton,
Cellulose-based chemical fibers such as viscose rayon and acetate are exemplified. On the other hand, examples of the synthetic fibers include polyethylene fibers, polypropylene fibers, polyester fibers, polyamide fibers, polyacrylonitrile fibers, polyvinyl alcohol fibers, and at least two kinds of these synthetic fibers in a core-sheath type. Examples thereof include composite fibers, fibers in which at least two kinds of these synthetic fibers are mixed, and the like. Of these fibrous base materials, various hydrophilic cellulose fibers can be preferably used. When a fibrous base material having no hydrophilicity is used, its surface may be subjected to a hydrophilizing treatment with a hydrophilizing agent such as a surfactant.

In the absorbent body 4, the amount of the super absorbent polymer used is 45% by weight or more of the total weight of the absorbent body 4. As described above, in the conventional disposable diaper, the amount of the superabsorbent polymer used is 10 to 30% by weight based on the total weight of the absorbent due to a problem such as occurrence of gel blocking phenomenon.
In the present invention, the occurrence of gel blocking does not pose a problem even if the amount of superabsorbent polymer used is as high as 45% by weight or more. As a result, the absorbent article of the present invention becomes a thin article having excellent reabsorbability. The amount of the super absorbent polymer used is preferably 45 to 90% by weight, more preferably 50 to 80% by weight.

On the other hand, the amount of the fibrous base material used is preferably 10 to 55% by weight, more preferably 20 to 50% by weight, based on the total weight of the absorbent body 4. When the amount of the fibrous base material used is less than 10% by weight, the entanglement of the fibrous base material in the absorbent body is reduced, so that the absorbent body 4 is cracked or biased during use of the absorbent article. In some cases, if it exceeds 55% by weight, it may not always be a thin absorbent article, so that it is preferably within the above range.

The absorbent body 4 may be composed only of the fibrous base material and the superabsorbent polymer, or may have the fibrous base material and the superabsorbent polymer as main constituent elements. In addition, other constituent components may be included within a range that does not impair the object and effects of the present invention. Examples of the other constituent components include pulp powder, organic powder such as natural polysaccharides, zeolite, activated carbon, inorganic powder such as fine particle silica, colorant, bactericide, and fragrance.

The superabsorbent polymer satisfies the above conditions 2) and 3), that is, 2) the superabsorbent polymer has a physiological saline absorption capacity of 25 g / g by a centrifugal dehydration method.
Above, and 3) 0.5 g of the super absorbent polymer is filled in a cylinder having a cross-sectional area of 4.91 cm ² (inner diameter 25 mmφ) together with physiological saline, and the super absorbent polymer is saturated with the physiological saline. The swelling of the superabsorbent polymer is allowed to take place, and the liquid passage time when 50 ml of physiological saline is passed after the swollen superabsorbent polymer has settled is 20 seconds or less.

The water absorption amount under the above condition 2) is a measure of the water absorption performance of the superabsorbent polymer. If the water absorption amount is less than 25 g / g, the amount of the superabsorbent polymer used will be absorbed. Even if it is 45% by weight or more of the total weight of the body 4, it is impossible to obtain a sufficient absorbent capacity as an absorbent article. The larger the water absorption amount, the more preferable, but it is preferably 35 to 65 g / g in a practical range. still,
The method for measuring the amount of water absorption will be described in detail in Examples described later.

The liquid passage time under the above condition 3) is a measure of the occurrence of gel blocking phenomenon of the super absorbent polymer. When the liquid passage time exceeds 20 seconds, the amount of the super absorbent polymer used. 4 of the total weight of the absorber 4
When it is 5% by weight or more, a gel blocking phenomenon occurs and the absorption performance of the superabsorbent polymer is impaired. The shorter the liquid passage time, the better, but a practical range is preferably 2 to 20 seconds, and more preferably 2 to 15 seconds. The method of measuring the liquid passage time will be described in detail in Examples described later.

There are no particular restrictions on the type of superabsorbent polymer as long as it satisfies the above conditions 2) and 3). For example, as the super absorbent polymer, sodium polyacrylate, (acrylic acid-vinyl alcohol) copolymer, sodium polyacrylate crosslinked product, (starch-acrylic acid) graft polymer, (isobutylene-maleic anhydride) copolymer is used. Examples thereof include polymers and saponified products thereof, potassium polyacrylate, and cesium polyacrylate. In order to satisfy the above conditions 2) and 3), for example,
A cross-linking density gradient may be provided on the surface of the particles of the superabsorbent polymer, or the particles of the superabsorbent polymer may be formed into non-spherical amorphous particles. Specifically, JP-A-7-184956, column 7, 28. The method described in line to column 9, line 6 can be used.

The fibrous base material and the super absorbent polymer may be present in the absorbent body 4 in a mixed state. Alternatively, the superabsorbent polymer may be present as a layer in the fibrous base material. Further, the fibrous base material may be in a defibrated and laminated state, or may be in a sheet-like state such as paper or nonwoven fabric.

In the absorbent body 4, the superabsorbent polymer preferably has a spray basis weight of 10 to 1000 g / m ² from the viewpoint of obtaining a practical absorbent capacity as an absorbent article. More preferably, it is 500 g / m ² .

In the absorbent body 4, the highly water-absorbing material is used.
The amount of limmer used is relative to the amount used of the above fibrous base material.
The thickness is smaller than that of conventional absorbers.
can do. As a result, the disposable diaper 1
It can be made thinner than the conventional one. Specifically
The thickness of the disposable diaper 1 is 2.5 g / cm 2. ^Two
It is preferably 1.0 to 4.0 mm under load,
More preferably, it will be 1.0 to 3.0 mm.

Next, a disposable diaper as a second embodiment of the absorbent article of the present invention will be described with reference to FIG.
Here, FIG. 3 is a schematic diagram showing a main part of a cross section in the width direction of a disposable diaper as a second embodiment of the absorbent article of the present invention. In the second embodiment, only the points different from the first embodiment will be described, and the same points will not be described in detail, but the detailed description of the first embodiment is appropriately applied. In addition, in FIG.
The same reference numerals are given to the same members.

In the second embodiment shown in FIG. 3, the absorber 4 comprises two or more layers (in FIG.
Layer), at least one layer is the layer 15 made of the above fibrous base material (hereinafter, this layer is referred to as “fibrous base material layer”), and at least one other layer is made of the above super absorbent polymer. A layer 16 or a layer 16 made of a mixture of the superabsorbent polymer and the fibrous base material (hereinafter, this layer is referred to as “polymer-containing layer”), and these layers are alternately laminated. By using the absorbent body 4, even if the entanglement of the fibrous base material in the polymer-containing layer 16 is reduced as a result of absorbing the body fluid and the like and swelling of the super absorbent polymer, the fibrous base material is reduced. Since the entanglement of the fibrous base material in the layer 15 does not decrease, the absorber 4 is preferable because it is thin and cracks and unevenness are less likely to occur.

As shown in FIG. 3, in the absorbent body 4, the polymer-containing layer 16 is arranged on the side of the topsheet 2, and the fibrous base material layer 1 on the side of the backsheet 3.
5 are arranged. Then, the polymer-containing layer 16 and the fibrous base material layer 15 are in close contact with each other by press working.

The absorber 4 has one or more fibrous base material layers 15 (in FIG. 3, 1).
One). It is preferable that the total saturated water absorption of the fibrous base material layer 15 in the absorber 4 is 0.1 g / cm ² or more. If the total amount of saturated water absorption is less than 0.1 g / cm ² , the ability of the fibrous base material layer 15 to temporarily store the body fluid may be insufficient and leakage may occur. The saturated water absorption is preferably as large as possible, but more preferably 0.1 to 10 g / cm ² as a practical range.
The method for measuring the saturated water absorption amount will be described in detail in Examples described later.

The fibrous base material layer 1 in the absorbent body 4
5 may be a layer in which the fibrous base material is defibrated and laminated, or may be a sheet-like layer in which the fibrous base material is formed into a sheet shape such as paper or nonwoven fabric. Good. In particular, the fibrous base material layer 15 in the absorbent body 4 is preferably a sheet-like layer in which at least one layer thereof is made of hydrophilic fibers, for example, a paper or non-woven fabric layer such as absorbent paper. . By using such a sheet-like layer as the fibrous base material layer 15, the absorbent body 4 is actually used when the absorbent article is actually used, as compared with the case where a layer in which the fibrous base material is simply defibrated and deposited is used. It is preferable because cracking and unevenness are further less likely to occur. When the fibrous base material layer 15 is composed of a sheet-like layer, the sheet-like layer has a basis weight of 5 to 200 g / m ² of the absorbent body 4 when the absorbent article is actually used. From the viewpoint of shape retention and thinning, it is more preferably 10 to 100 g / m ² .

When the polymer-containing layer 16 in the absorbent body 4 is a layer made of the superabsorbent polymer, a small amount of water, latex or the like is added to the fibrous base material layer 15. After spraying an aqueous solution containing the binder component of 1 to wet the fibrous base material layer 15,
Forming by spraying a predetermined amount of the superabsorbent polymer,
It is preferable from the viewpoint of improving the adhesiveness of both layers. On the other hand, when the polymer-containing layer 16 is a layer composed of a mixture of the superabsorbent polymer and the fibrous base material, the amount of the superabsorbent polymer and the fibrous base material to be used is It is preferable that the water-soluble polymer is 50 to 95 parts by weight, the fibrous base material is 5 to 45 parts by weight, and the super absorbent polymer is 55 parts by weight.
˜75 parts by weight, and the fibrous base material is preferably 25 to 45 parts by weight. Further, in this case, in the polymer-containing layer 16, the super absorbent polymer is preferably uniformly dispersed in the polymer-containing layer 16.

Next, a disposable diaper as a third embodiment of the absorbent article of the present invention will be described with reference to FIG.
Here, FIG. 4 is a schematic view (corresponding to FIG. 3) showing a main part of a cross section in the width direction of the disposable diaper as the third embodiment of the absorbent article of the present invention. In the third embodiment, only the points different from the first and second embodiments will be described, and the same points will not be described in detail, but the detailed description of the first and second embodiments will be given. Applicable accordingly.
Further, in FIG. 4, the same members as those in FIGS. 1 to 3 are denoted by the same reference numerals.

In the third embodiment shown in FIG. 4, the absorber 4 is composed of three layers, and the three layers are layers of the superabsorbent polymer or the superabsorbent polymer and the fibrous material. A layer made of a mixture with a base material, that is, the polymer-containing layer 16 is laminated by sandwiching it between two layers of the same or different fibrous base materials, that is, the fibrous base material layers 15 and 15. It is a thing. By using the absorbent body having such a configuration, similar to the second embodiment, in addition to being thin, cracking and unevenness of the absorbent body 4 are less likely to occur, and the polymer-containing layer 16 is the fiber base material layer 15, 1
Since it is sandwiched between the absorbent cores 5, the super absorbent polymer is less likely to fall off from the absorbent core 4, which is preferable. In the two fibrous base material layers 15 and 15 sandwiching the polymer-containing layer 16 from both sides thereof, the type of fibrous base material used is
They may be the same or different depending on the type and application of the absorbent article.

The absorbent article of the present invention has been described above based on its preferred embodiment, but the present invention is not limited to the above embodiment, and various modifications can be made. For example, in the embodiment shown in FIG. 3, the absorbent body 4 is composed of one fibrous base material layer 15 and one polymer-containing layer 16, respectively. Two or more layers 16 may be used. Further, the absorbent article of the present invention may be applied to absorbent articles other than the above-mentioned disposable diapers, for example, sanitary napkins, incontinence pads, breast pads and the like.

[0041]

EXAMPLES The effectiveness of the absorbent article of the present invention will be illustrated below with reference to examples, but the present invention is not limited to these examples.

In the Examples and Comparative Examples described below, the water absorption amount of the physiological saline solution by the centrifugal dehydration method, the liquid passage time, and the saturated water absorption amount of the physiological saline of the fibrous base material layer were measured by the following methods. It was measured.

<Water Absorption of Superabsorbent Polymer by Centrifugal Dehydration Method> 1 g of the superabsorbent polymer was swollen with 150 ml of physiological saline for 30 minutes, put in a nylon mesh bag of 250 mesh, and centrifuged at 143 G with a centrifuge. After dehydration for 10 minutes, the total weight after dehydration was measured. Then, the water absorption amount (g / g) by the centrifugal dehydration method was calculated according to the following formula (I).

[0044]

[Equation 1]

<Liquid passage time of superabsorbent polymer> 0.5 g of superabsorbent polymer P was placed in a device 20 shown in FIG. 5 (viewlet consisting of a glass cylindrical tube having an inner diameter of 25 mm and a length of about 250 mm (cylindrical portion)). Was filled, and an excess amount of physiological saline W was injected to equilibrate and swell the superabsorbent polymer P. After equilibrium swelling of the superabsorbent polymer P, the liquid level is increased to 2
The cock was adjusted to 00 mm, and it was confirmed that the swollen superabsorbent polymer P had fully settled as shown in the figure. The cock was opened, and the physiological saline W was filled with the two marked lines L and M shown in FIG. The time during which the liquid passed (50 ml of liquid) was measured, and this measured value was used as the liquid passage time (seconds).

<Saturated water absorption of fibrous base material by physiological saline solution> A fibrous base material layer cut into 20 cm × 15 cm (300 cm ² ) was immersed in 150 ml of physiological saline solution for 30 minutes, and then a metal mesh of 80 mesh 30 on the top
It was drained for minutes, and the total weight after draining was measured. Then, the saturated water absorption (g / cm ² ) was calculated according to the following formula (II).

[0047]

[Equation 2]

[Example 1] The saturated absorption amount was 0.15 g / c.
After spraying a small amount of water on the m ² dry pulp nonwoven fabric sheet (a) (pulped and laminated pulp fibers bonded with a binder to form a sheet), the water absorption by the centrifugal dehydration method is 29 g. / G, superabsorbent polymer (I) having a liquid passage time of 12 seconds (sodium polyacrylate crosslinked particles having a high surface crosslink density) is uniformly dispersed to form a polymer-containing layer. did. Next, a pulp absorbent paper (b) having a saturated water absorption of 0.04 g / cm ² (absorbent paper obtained by making pulp) was laminated on the polymer-containing layer, and the obtained laminate was pressed. An absorbent body (a) for a disposable diaper was obtained. The amount of the super absorbent polymer (I) used was 59% by weight based on the total weight of the absorber (a).
The total saturated water absorption of the fibrous base material layer in the absorbent body (a) was 0.19 g / cm ² . Next, a hydrophilic non-woven fabric made of polypropylene as a surface sheet is arranged on the dry pulp nonwoven fabric sheet (a) side of the absorbent body (a), and a polyethylene film is arranged on the pulp absorbent paper (b) side as a back sheet. Then, a disposable diaper (A) was obtained. The obtained disposable diaper (A) is
The thickness under a load of 2.5 g / cm ² was 2.0 mm.

Example 2 Instead of the superabsorbent polymer (I) in Example 1, the water absorption amount by the centrifugal dehydration method was 3
Super absorbent polymer (II) having a liquid passage time of 17 seconds at 7 g / g [crosslinked particles of sodium polyacrylate,
The absorbent for a disposable diaper (b) and the disposable diaper (B) are used in the same manner as in Example 1 except that those having a high cross-linking density of the surface portion, but having a lower cross-linking density than the super absorbent polymer (I) are used. ) Got. The amount of the super absorbent polymer (II) used in the absorber (b) was 59% by weight based on the total weight of the absorber (b). In addition, the total saturated water absorption of the fibrous base material layer in the absorbent body (b) was 0.19 g / cm ² . Also, the disposable diaper (B) has a thickness of 2.0 mm under a load of 2.5 g / cm ^2.
Met.

Example 3 A small amount of water was sprayed onto the dry pulp nonwoven fabric sheet (a), and then the superabsorbent polymer (II) was sprayed uniformly to form a polymer-containing layer. Next, a water-repellent polypropylene non-woven fabric (c) is laminated on the polymer-containing layer, and the obtained laminate is pressed,
An absorbent body (c) for a disposable diaper was obtained. The amount of the super absorbent polymer (II) used is 5 based on the total weight of the absorber (c).
It was 6% by weight. The total saturated water absorption of the fibrous base material layer in the absorbent body (c) was 0.15 g / cm ² . Next, a disposable diaper (C) was obtained in the same manner as in Example 1 except that the dry pulp non-woven fabric sheet (a) side of the absorbent body (c) was the top sheet side. The obtained disposable diaper (C) had a thickness of 2.2 mm under a load of 2.5 g / cm ² .

Example 4 Wood pulp was defibrated and laminated to obtain a pulp layer (d) having a saturated water absorption of 0.12 g / cm ² . Then, a mixture of defibrated wood pulp and superabsorbent polymer (I) was laminated on the pulp layer (d) to form a polymer-containing layer. The obtained laminated body was pressed to obtain a disposable diaper absorbent body (d). The amount of the super absorbent polymer (I) used is 63% of the total weight of the absorber (d).
% By weight. The total saturated water absorption of the fibrous base material layer in the absorber (d) was 0.12 g / cm ² . Next, the pulp layer (d) in the absorber (d)
A disposable diaper (D) was obtained in the same manner as in Example 1 except that the side was the surface sheet side. The obtained disposable diaper (D) has a thickness of 2.5 m under a load of 2.5 g / cm ^2.
m.

Example 5 A small amount of water was sprayed on the pulp absorbent paper (II), and then the superabsorbent polymer (II) was uniformly sprayed to form a polymer-containing layer. Then, a hydrophilic polypropylene non-woven fabric (e) having a saturated water absorption of 0.08 g / cm ² is laminated on the polymer-containing layer, and the obtained laminated body is pressed to obtain a disposable diaper absorbent body (e). ) Got. The amount of the super absorbent polymer (II) used was 67% by weight based on the total weight of the absorber (e). The total saturated water absorption of the fibrous base material layer in the absorber (e) was 0.12 g / cm ² . Next, a disposable diaper (E) was obtained in the same manner as in Example 1 except that the pulp absorbent paper (b) side of the absorbent body (e) was the top sheet side. The disposable diaper (E) obtained is 2.
The thickness under a load of 5 g / cm ² was 1.7 mm.

Example 6 The superabsorbent polymer (I) was uniformly dispersed on the pulp layer (d) to form a polymer-containing layer. Then, another pulp layer (d) was laminated on the above polymer-containing layer. After pressing the obtained laminate, a small amount of a latex-based adhesive is sprayed from the upper surface and the lower surface of the laminate and dried to obtain a disposable diaper absorbent body (f) in which the pulp layer (d) is made into a nonwoven fabric. It was The amount of the super absorbent polymer (I) used was 53% by weight of the total weight of the absorber (f). In addition, the total saturated water absorption of the fibrous base material layer in the absorber (f) was 0.24 g / cm ² . Next, a disposable diaper (F) was obtained in the same manner as in Example 1 except that the lower surface pulp layer (d) side of the absorbent body (f) was the surface sheet side. Obtained disposable diaper (F)
Had a thickness of 2.6 mm under a load of 2.5 g / cm ² .

Comparative Example 1 Instead of the pulp layer (d) in Example 4, a pulp layer (f) having a saturated water absorption of 0.40 g / cm ² was obtained by defibrating and stacking wood pulp. An absorbent body (g) for a disposable diaper and a disposable diaper (G) were obtained in the same manner as in Example 4 except that it was used. The amount of the super absorbent polymer (I) used in the absorber (g) was 36% by weight based on the total weight of the absorber (g). The total saturated water absorption of the fibrous base material layer in the absorber (g) was 0.40 g / cm ² . Also,
The disposable diaper (G) had a thickness of 5.5 mm under a load of 2.5 g / cm ² .

[Comparative Example 2] Instead of the superabsorbent polymer (I) in Example 1, the water absorption amount by the centrifugal dehydration method was 3
Super absorbent polymer (III) (sodium polyacrylate crosslinked particles having a liquid passage time of 33 seconds at 0 g / g,
Absorbents for a disposable diaper (h) and a disposable diaper (H) were obtained in the same manner as in Example 1 except that (one that was relatively uniformly crosslinked from the inside to the surface) was used.
The amount of the super absorbent polymer (I) used in the absorber (h) is 59% by weight based on the total weight of the absorber (h).
Met. The total saturated water absorption of the fibrous base material layer in the absorbent body (h) was 0.19 g / cm ² .
Further, the disposable diaper (H) had a thickness of 2.0 mm under a load of 2.5 g / cm ² .

[Comparative Example 3] Instead of the highly water-absorbing polymer (I) in Example 4, the water absorption amount by the centrifugal dehydration method was 2
Super absorbent polymer (IV) having a liquid passage time of 14 seconds at 0 g / g [crosslinked particles of sodium polyacrylate,
In the same manner as in Example 4, except that a polymer that is relatively uniformly crosslinked from the inside to the surface, provided that the crosslinking density is considerably higher than that of the superabsorbent polymer (III),
An absorbent body for a disposable diaper (i) and a disposable diaper (I) were obtained. The amount of the super absorbent polymer (IV) used in the absorber (i) was 63% by weight based on the total weight of the absorber (i). The total saturated water absorption of the fibrous base material layer in the absorber (i) is 0.12 g / cm.
^{Was 2} . In addition, disposable diaper (I) is 2.5g
The thickness under a load of / cm ² was 2.5 mm.

The disposable diapers of Examples 1 to 6 and Comparative Examples 1 to 3 were evaluated for urine leakage. Evaluation,
The test was conducted by conducting a usage test on 200 disposable diapers in total for 10 monitors. As a result, and 2.5 g / cm of each disposable diaper
Table 1 shows the thickness under ^two loads.

[0058]

[Table 1]

[0059]

EFFECTS OF THE INVENTION According to the absorbent article of the present invention, although the ratio of the super absorbent polymer in the absorbent body is high, the absorption performance inhibiting phenomenon such as gel blocking phenomenon does not occur, and the absorbent article also has a reabsorbability. It is excellent, and the absorbent article can be thinned.

[Brief description of drawings]

FIG. 1 is a perspective view showing a disposable diaper as a first embodiment of an absorbent article of the present invention.

FIG. 2 is a partially cutaway plan view showing a developed state of the disposable diaper shown in FIG.

FIG. 3 is a schematic diagram showing a main part of a cross section in the width direction of a disposable diaper as a second embodiment of an absorbent article of the present invention.

FIG. 4 is a schematic diagram showing a main part of a cross section in the width direction of a disposable diaper as a third embodiment of an absorbent article of the present invention (FIG. 3).
FIG.

FIG. 5 is a view showing an apparatus for measuring a liquid passage time of a super absorbent polymer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Disposable diaper 2 Surface material 3 Back material 5 Ventral waist part 5'Back waist part 6 Waist elastic member 7,7 'Waist gather 8 Leg elastic member 9,9' Leg gather 10 Fastening tape 11 Landing tape

Claims (7)

[Claims] 1. An absorbent article having a liquid-permeable top sheet, a liquid-impermeable back sheet, and a liquid-retaining absorber interposed between these sheets, wherein the absorber is the following 1). 2. An absorbent article, which satisfies the condition (1) and the superabsorbent polymer contained in the absorber satisfies the following conditions (2) and (3). 1) The absorbent body mainly comprises a fibrous base material and a super absorbent polymer, and 45% by weight of the total weight of the absorbent body.
The above is the super absorbent polymer. 2) The amount of physiological saline solution absorbed by the centrifugal dehydration method of the superabsorbent polymer is 25 g / g or more. 3) Cross-sectional area 4.91c of 0.5 g of the super absorbent polymer
A cylinder of m ² (inner diameter 25 mmφ) was filled with physiological saline, and the superabsorbent polymer was swollen with the physiological saline until it reached a saturated state, and 50 ml of physiological saline was added after the swollen superabsorbent polymer was precipitated. The liquid passage time when passing through is 20 seconds or less. 2. The water absorption amount is 35 to 65 g / g,
The absorbent article according to claim 1. 3. The absorbent body comprising two or more layers, at least one layer comprising the fibrous base material, and at least one other layer comprising the superabsorbent polymer or The absorbent article according to claim 1 or 2, which is a layer formed of a mixture of the superabsorbent polymer and the fibrous base material, and these layers are alternately laminated. 4. The absorbent body is composed of three layers, and the three layers are composed of a layer of the superabsorbent polymer or a layer of a mixture of the superabsorbent polymer and the fibrous base material. The absorbent article according to any one of claims 1 to 3, which is laminated by being sandwiched between two layers made of the same or different fibrous base materials. 5. The absorbent body has a layer made of one or more fibrous base materials, and the sum of saturated water absorption by physiological saline of the fibrous base material layer is 0.1 g. / Cm ²
The absorbent article according to claim 3, which is the above. 6. The absorbent article according to claim 4, wherein the sum of saturated water absorption by the physiological saline of the two layers made of the fibrous base material is 0.1 g / cm ² or more. 7. The absorbent article according to claim 3, wherein at least one of the layers made of the fibrous base material is a sheet-shaped layer made of hydrophilic fibers.