JP3505868B2 - Absorbent articles - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to absorbent articles, and more particularly to absorbent articles used for diapers, pads for incontinence, sanitary napkins, bed sheets, pet sheets and the like. is there.

[0002]

2. Description of the Related Art Conventional disposable diapers, which have been one of the absorbent articles, include a cotton-like pulp, a super absorbent polymer, a liquid-permeable top sheet and a liquid-impermeable back sheet. It has a structure in which an absorbent body made of a hydrophilic sheet or the like is arranged, and urine, body fluid and loose feces are absorbed by the absorbent body through the surface sheet. In this case, the absorbent body needs to receive urine, body fluids and loose stools and retain the skin without rewetting. As the absorbent, it is known that a mixture of cotton-like pulp and a super-absorbent polymer is used alone, or that the cotton-like pulp is placed on the absorbent, the speed until the liquid is completely absorbed. (Hereinafter referred to as "absorption rate") is slow, and the return of urine, body fluid and loose stool from the absorbent body to the surface (hereinafter referred to as "wet back") is also large. It causes discomfort to persons and, in the case of infants, contributes to skin irritation.

A method of changing the superabsorbent polymer in the absorber in order to quickly absorb the urine of the wearer (Japanese Patent Laid-Open Publication No. 6-58242).
No. 1-167002), a method of changing the pulp density (Japanese Patent Laid-Open No. 61-34203), and the like. These methods are effective for urine but not for loose stool. As a method of absorbing urine and loose stools, a method of changing the superabsorbent polymer distribution of the fluid storage lower layer on the back sheet side (JP-A-62-62)
No. 32950) is disclosed, but the sufficient effect is not always obtained. Further, a method of changing the amount of pulp in the central portion of the absorber is disclosed (Japanese Patent Laid-Open No. 2-111361), but since all the absorbers are formed with the same composition containing a superabsorbent polymer, It is effective against urine, which is mostly water, but it is difficult to absorb loose stool, which has less water than urine and is highly viscous. Also,
A method for isolating feces by changing the structure of a diaper is disclosed (Japanese Patent Laid-Open No. 4-300543). Some of these have a top sheet with an opening to separate and hold the stool, but the opening may be crushed when the wearer is sitting, and the stool may not be held. The number of processing steps increases and the production efficiency decreases.

[0004]

As described above, in the conventional disposable diaper, the absorption speed of the top sheet for absorbing urine, body fluid and loose feces into the absorbent body is slow, and the dry touch property of the top sheet is low. There was a problem that was not good.

The object of the present invention is to overcome the above-mentioned problems of the conventional diaper for use, and to improve the spot absorbency and absorption speed of the top sheet for absorbing urine, body fluid and loose feces, An object is to provide an absorbent article in which the dry touch property of the top sheet is remarkably improved.

[0006]

SUMMARY OF THE INVENTION The present invention provides an absorbent article in which an absorbent body is arranged between a liquid-permeable top sheet and a liquid-impermeable back sheet, wherein the absorbent body is the liquid-permeable material. A first absorbent body in contact with the water-permeable top sheet and a second absorbent body in contact with the liquid-impermeable back sheet, the first absorbent body being fused at the points where the hydrophilic synthetic fibers intersect. 12 g / cm ^{2 with a} thickness of 0.3 to 3.0 mm under a load of 12 g / cm ^2
2 Average weight density under 0.01-0.05g / c
m ³ and the first absorbent body further comprises a surface layer of the first absorbent body in contact with the liquid permeable top sheet and a back surface layer of the first absorbent body in contact with the second absorbent body, The surface layer of the one absorbent body has a higher density than the back surface layer of the first absorbent body, and the second absorbent body contains the cotton-like pulp and the superabsorbent polymer in an amount of 61% by weight or more of the second absorbent body. 10 to 500 based on 100 parts by weight of the cotton-like pulp.
An absorbent article is characterized by containing a part by weight of the superabsorbent polymer, and being formed by laminating and integrating the first absorbent body and the second absorbent body. Further, in the present invention, the first absorbent body includes a synthetic fiber having a circular cross section, and further, at least one of a surface layer of the first absorbent body and a back surface layer of the first absorbent body is provided with a modified cross-section synthetic fiber in each layer. And 25 to 75% by weight of the absorbent article.

The absorbent article of the present invention has an absorbent body between a liquid-permeable top sheet and a liquid-impermeable back sheet. In the present invention, the absorbent body is composed of a first absorbent body in contact with the liquid-permeable top sheet and a second absorbent body in contact with the liquid-impermeable back sheet, and the first absorbent body is a liquid. It consists of the surface layer of the first absorbent body in contact with the permeable top sheet and the back surface layer of the first absorbent body in contact with the second absorbent body, and the surface layer of the first absorbent body is more than the back surface layer of the first absorbent body. Is also denser. The second absorbent body is composed mainly of cotton-like pulp and super absorbent polymer. The absorbent article of the present invention having the above structure, the back surface of the liquid-permeable top sheet, the high density portion of the first absorbent body is in contact, the surface of the second absorbent body, the first absorbent Since the parts with low body density are in contact with each other, urine, body fluids, loose stools, etc. in the top sheet are quickly spot-absorbed by the surface layer of the first absorbent body and pass through at a high speed, then the back surface of the first absorbent body. Immediately diffused in the layer, the second absorbent body collects the top sheet and the first absorbent body such as urine, body fluid and loose feces. Therefore, urine, body fluid, loose stools, etc. do not stagnate on the top sheet, and the dry touch property of the top sheet is significantly improved.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the absorbent article of the present invention will be described in detail with reference to the drawings using a diaper that is used as an example, but the present invention is not limited thereto.

FIG. 1 is a plan view showing a state in which the diaper is unfolded after being used. As shown in FIG. 1, the disposable diaper comprises an absorbent body 2 arranged between a liquid-permeable top sheet 1 and a liquid-impermeable back sheet 5. FIG. 2 is a cross-sectional view of the disposable diaper shown in FIG. 1 taken along line xx ′. As shown in FIG. 2, the disposable diaper has a liquid-permeable top sheet 1 and a liquid-impermeable back sheet 5.
The absorber 2 is arranged between the two. The absorbent body is composed of the first absorbent body 3 in contact with the liquid-permeable top sheet 1 and the second absorbent body 4 in contact with the liquid-impermeable back sheet 5. FIG. 3 shows an enlarged cross-sectional view of the absorber shown in FIG. The first absorbent body 3 is composed of a surface layer 3a of the first absorbent body which is in contact with the liquid-permeable top sheet 1 and a back surface layer 3b of the first absorbent body which is in contact with the second absorbent body 4. The surface layer 3a has a higher density than the back surface layer 3b of the first absorber. The second absorbent body 4 is mainly composed of the cotton-like pulp 6 and the super absorbent polymer 7. The disposable diaper having the above-mentioned configuration, the back surface of the liquid-permeable top sheet, the high density portion of the first absorbent body is in contact, the surface of the second absorbent body, the first absorbent body Urine, body fluids and loose stools in the top sheet are spot-absorbed first by the surface layer of the first absorbent and pass through at a high speed because the low-density portions are in contact, and then by the back surface layer of the first absorbent. Immediately diffused, the urine, body fluid, loose stool, etc. of the top sheet and the first absorbent body are further collected by the second absorbent body. Therefore, urine, body fluid, loose stools, etc. do not stagnate on the top sheet, and the dry touch property of the top sheet is significantly improved.

Materials constituting the disposable diaper of the present invention will be described below. Liquid-permeable top sheet The top sheet used is a liquid-permeable sheet such as a non-woven fabric, a woven fabric, a mesh sheet, a porous foam or a porous film. The constituent fibers may be polypropylene, polyethylene, polyester, or a composite fiber composed of two or more components such as polyester, polypropylene, polyethylene, etc. In particular, polyester / polyester, polyester / polyethylene, polypropylene / polyethylene composite fibers have high strength. From the viewpoint of the above, it is not particularly limited. Further, natural fibers (for example, wood fibers, cotton fibers) may be used, and they can be manufactured from a wide range of materials such as a combination of synthetic fibers and natural fibers. Although the manufacturing method and the shape thereof are not limited, in any case, the liquid-permeable top sheet is a portion which is in direct contact with the skin, so that it is suitable that the top sheet is soft and has a good touch. The basis weight of the liquid-permeable top sheet is 10 to 60 g /
m ² is preferred. If the grammage is less than 10 g / m ² , wet back from the absorbent is deteriorated, which is not suitable.
Further, if the basis weight exceeds 60 g / m ² , the moisture remaining on the top sheet is large, so that the dry touch property is deteriorated and not only the wearer is uncomfortable, but also dermatitis is caused. The fiber diameter of the constituent fibers is 0.5 to 10.
Denier is preferred. When the fiber diameter is less than 0.5 denier, the density is high and the absorption rate is low, so that leakage tends to occur. On the other hand, if the fiber diameter exceeds 10 denier, it is unsuitable because the skin feel becomes poor.

The absorbent body comprises a first absorbent body which is in contact with the liquid permeable top sheet and a second absorbent body which is in contact with the liquid impermeable back sheet, and the first absorbent body is liquid permeable. Of the first absorber, which is in contact with the top sheet, and the back layer of the first absorber, which is in contact with the second absorber. The first absorbent body is fused and maintained in a web form at the points where the hydrophilic synthetic fibers intersect, and has a thickness of 0.3 to 12 g / cm ² under a load.
At 3.0 mm, the average density under load of 12 g / cm ² is 0.01 to 0.05 g / cm ³ , and further, the surface layer of the first absorbent body in contact with the liquid-permeable top sheet is The density is higher than that of the back surface layer of the first absorbent body which is in contact with the second absorbent body. Average density of the first absorber is 0.05g
If it exceeds / cm ³ , it is not suitable because the absorption rate decreases. On the other hand, if it is less than 0.01 g / cm ³ , the density of the surface layer of the first absorbent body becomes small, so that urine, bodily fluid and loose feces cannot be quickly absorbed from the top sheet, and the first absorbent body easily leaks. When the thickness of the first absorbent body under a load of 12 g / cm ² exceeds 3.0 mm, the urine, body fluid and loose stools from the top sheet cannot be quickly absorbed by the absorbent body and are easily leaked. Also, 0.3
If it is less than mm, it is not suitable because the absorption rate decreases.

The synthetic fiber used in the first absorbent body may be polypropylene, polyethylene, polyester, or a composite fiber composed of two or more components such as polyester, polypropylene and polyethylene, and particularly polyester / polyester, polyester. / Polyethylene, polypropylene / polyethylene composite fiber is preferable from the viewpoint of strength. Further, as the fiber diameter of the constituent fibers,
From the viewpoint of manufacturing, it is preferable that the length is 1.5 to 10 denier and the length is about 10 to 100 mm. As a method for hydrophilizing these synthetic fibers and composite fibers, a hydrophilizing agent is applied to the synthetic fibers and the composite fibers by spraying, or the manufactured first absorber is applied by spraying, foaming, impregnating, or the like. There is a way.

Further, the first absorbent body contains synthetic fibers having a circular cross-sectional shape, and further, at least one of the surface layer of the first absorbent body and the back surface layer of the first absorbent body has a cross-sectional shape. Each layer contains 25 to 75% by weight of synthetic fibers having various shapes and having irregular cross sections. In this case, it is preferable that the back surface layer of the first absorbent body contains more synthetic fibers of irregular cross section than the front surface layer of the first absorbent body, and it is more preferable that the back surface layer of the first absorbent body contains only synthetic fiber. preferable. Since the back surface layer of the first absorbent body contains a large amount of synthetic fibers having a modified cross section, the back surface layer of the first absorbent body has a lower density than the front surface layer of the first absorbent body. The reason for this is that, for example, in the case of the same denier, since the synthetic fiber having the irregular cross section has a larger cross-sectional area than the synthetic fiber having the circular cross section, the density becomes low when the synthetic fiber having the irregular cross section is included. There is also a method of increasing the fiber diameter of a synthetic fiber having an irregular cross section than that of a synthetic fiber having a circular cross section. When the content of the synthetic fiber having a modified cross section with respect to each layer is less than 25% by weight,
Not suitable due to reduced absorption rate. Further, when the content of the synthetic fiber having a modified cross section with respect to each layer exceeds 75% by weight, the density of the surface layer of the first absorbent layer becomes small, and the top sheet quickly absorbs urine, body fluid and loose feces. It becomes impossible and leaks easily. Examples of synthetic fibers of irregular cross section include polypropylene, polyethylene, polyester, acrylic resin, nylon resin, etc.
The cross-sectional shape is preferably T-shaped, W-shaped, H-shaped, diamond-shaped, amoeber-shaped or the like, but is not particularly limited.

The second absorbent body contains the cotton-like pulp and the superabsorbent polymer in an amount of 61% by weight or more of the second absorbent body. Further, 60% by weight or less of the heat-fusible substance may be mixed with the cotton-like pulp. The target absorbent body may constitute the second absorbent body containing only the cotton-like pulp and the superabsorbent polymer. 61% by weight of secondary absorbent cotton pulp and super absorbent polymer
When it is less than, it becomes impossible to retain urine, body fluids and loose stools,
It is not suitable because it easily leaks. Furthermore, the blending amount of the superabsorbent polymer is 10 to 500 parts by weight, preferably 15 to 300 parts by weight, based on 100 parts by weight of the cotton-like pulp, and the amount of the superabsorbent polymer is uniform in the cotton-like pulp, Alternatively, it may be distributed in a part. When the super-absorbent polymer absorbs and swells, its mutual interference is minimized, and it rarely forms a permeation barrier through continuous contact, and permeates and absorbs urine and body fluid in three dimensions. .

The cotton-like pulp used in the second absorbent is a pulp having a fiber length of 5 mm or less obtained by defibrating a chemical pulp sheet or a mechanical pulp sheet with a crusher. As the pulp material, not only softwood but also hardwood, straw, bamboo and kefna are applied. The amount of this pulp used varies depending on the intended absorber, for example, whether it is used alone, a plurality of layers is used, or a combination is used, but it is generally set to 50 to 500 g / m ^2. . Examples of the superabsorbent polymer used for the second absorber include starch-based, cellulose-based and synthetic polymer-based polymers. That is, starch-acrylic acid (salt) graft copolymer, saponification product of starch-ethyl acrylate graft copolymer, saponification product of starch-methyl methacrylate acid graft copolymer, saponification product of starch-acrylonitrile graft copolymer. , Saponified starch-acrylamide graft copolymer, saponified starch-acrylonitrile-2-acrylamido-2-methylpropanesulfonic acid graft copolymer, acrylic acid (salt) polymer, acrylic acid cross-linked poly Examples include cross-linked products of ethylene oxide and sodium carboxymethyl cellulose, and cross-linked products of polyvinyl alcohol-maleic anhydride reaction products. It absorbs more than 20 times its own weight of urine, body fluid and water, and sodium polyacrylate type is most suitable from the viewpoint of absorption performance.

As the heat-fusible substance, fibrous substances are preferable in consideration of mixing with the cotton-like pulp. Examples of the heat-fusible substance include polypropylene, polyethylene, polyester, polyvinylidene, acrylic resin, nylon resin and the like. Alternatively, a composite fiber composed of two or more components such as polyester, polypropylene and polyethylene may be used, and in particular, a composite fiber of polyester / polyester, polyester / polyethylene and polypropylene / polyethylene is preferable from the viewpoint of strength. The fiber diameter is preferably about 1 to 5 denier, and the fiber length is 3 to 30 mm, which is suitable for mixing with the cotton-like pulp, but is not particularly limited. By thermocompression-bonding these mat layers at a pressure of a certain level or higher, a skeletal structure of a heat-fusible substance is formed, and the mat layer itself can have strength even when wet. The method of thermocompression bonding is not particularly limited, such as a hot press roll, a hot embossing press roll, a hot air dryer, a microwave heater, an infrared heater, etc., but the heat is uniformly transferred to the mat layer, and the heat fusible substance is It suffices if it can be melted to form a skeletal structure.

Further, depending on the intended absorber, as shown in FIG. 3, it may be wrapped with a hydrophilic sheet. For example, a hydrophilic sheet such as tissue, absorbent paper or hydrophilic non-woven fabric may be used.

As a method for producing the first absorbent body, first, webs having different densities are stacked so that the surface layer of the first absorbent body has a higher density than the back surface layer of the first absorbent body, The first absorber is manufactured by integration with heat or the like. The front surface layer of the first absorbent body and the back surface layer of the first absorbent body are integrated by superposing two types of webs forming both layers, and fibers are fused by heat treatment to form a single layer. Other bonding methods include bonding by binder treatment, high-speed water jetting, and needle treatment, but are not particularly limited. Also, instead of using two types of webs, a single-layer web is used, and a high density is applied to the front part so that the fibers do not melt. A back part is lower than the front part. It can also be carried out by a heat treatment method of applying a temperature to form a low-density layer.

Then, on the back layer side of the obtained first absorber,
After the cotton-like pulp which is the main component of the second absorber and the super absorbent polymer are laminated, they are integrated. The lamination method is formed by a conventional method such as air forming, but is not particularly limited. As a compression method, compression with a press roll is advantageously carried out, but it is a continuous flat surface in which the density of the second absorbent body is made substantially uniform over the whole by a roll having a smooth peripheral surface. You can
The pattern may be embossed with a roll having an uneven peripheral surface so that the density of the second absorbent body is partially different and the urine, the body fluid, and the loose stool are guided in the longitudinal and oblique directions. In the case of embossing, the compressed part and the non-compressed part are continuous,
It may be non-continuous.

Further, as shown in FIG. 1, the first absorber is
It may be located in a region above the second absorbent body and its size may be equal to or smaller than that of the second absorbent body. urine,
If it is known where bodily fluids and loose stools are excreted, only that part may be installed.

Liquid-impermeable backsheet The backsheet used is a material in which a liquid-impermeable film such as polyethylene is laminated with a non-woven fabric, a woven fabric, or the like.
Further, any non-woven fabric or woven fabric having moisture resistance may be used. Also,
It may be embossed in a pattern to give it a cloth-like appearance or may be matte-finished. When a film is used, a known breathable film that is impermeable but allows only water vapor to pass may be used, and it is more preferable to prevent stuffiness.

In the members described above, for example, the top sheet and the absorber, and the absorber and the back sheet are adhered to each other in whole or in part by hot melt adhesion, and the adhesive is starch. A water-soluble glue such as a system or CMC (carboxymethyl cellulose), or a highly fluid adhesive may be used. The disposable diaper (absorbent article) of the present invention can achieve the effect of the present invention for the first time by combining the liquid-permeable top sheet and the absorber (first absorber and second absorber) described above. Becomes

[0023]

EXAMPLES The effects of the present invention will be described in detail below with reference to examples. In addition, as an evaluation item in the examples, artificial stool was used to evaluate the residual amount, and further, artificial urine was used to evaluate the absorption rate, wet back, and sensation of slats. The size of the diaper to be used is as follows: liquid-permeable top sheet and liquid-impermeable back sheet: width x length 30 x 40 cm, sandwiched absorbent body width x length 15 x The thing of 35 cm was used. The residual amount here means 30 m of artificial loose stool at 1 ml / sec from the distance of 1 cm in height to the center of a used diaper in which the weight of the top sheet was measured in advance.
1 drop, and 2 minutes after that, the top sheet was peeled off, the weight was measured, and the residual amount of artificial loose feces on the top sheet was measured. The artificial loose stool used here is as follows. Artificial loose stool composition (% by weight) Bentonite 5.0% Mayonnaise (commercially available) 5.0% The balance is water (prepared to have a viscosity of 200 cps) Absorption rate is a hole in the center of the diaper A perforated stainless steel plate (thickness 9 mm, hole diameter 25 mm) was placed, and the time until 50 cc of artificial urine was absorbed by the diaper was repeatedly measured 3 times every 30 minutes.
The wet back means that the absorbent diaper whose absorption rate was measured (50 cc absorbed three times) was left for 30 minutes and then used to filter the 10 × 10 cm square filter paper (made by Toyo Roshi Kaisha, No. 63) in the center of the diaper. ) 10 sheets, and then 0.05kg /
The amount of liquid transferred to the filter paper was measured after applying a pressure of cm ² and leaving it for 5 minutes. The feeling of salat means that after measuring the absorption rate (absorbing 50 cc three times), the surface of the topsheet is lightly touched by hand and the dryness (feeling of salat)
Was judged by sensory evaluation. The judgment criteria are the following three levels (○,
It was divided into Δ and ×). Sarat feeling judgment criteria ○: Dry △: Wet ×: Quite damp The artificial urine used here is as follows. Artificial urine composition (wt%) Urea 1.9% NaCl 0.8% CaCl ₂ 0.1% MgSO ₄ 0.1% The balance is water

Example 1 As a liquid-permeable top sheet hydrophilic fiber, a composite fiber having a fiber diameter of 2 denier and a fiber length of 51 mm and made of polyester / polyethylene, which has been hydrophilized by spray coating, was used.
A topsheet with g / m ² was obtained.

Absorber As the first absorber of the absorber, a synthetic fiber having a circular cross section with a fiber diameter of 2 denier and a fiber length of 51 mm, which is composed of hydrophilic polyester / polyethylene composite fibers hydrophilized by spray coating, is used. Manufactured with a thickness of 0.40 m
m, basis weight 12.0 g / m ² , density 0.030 g / cm ³ surface layer of the first absorbent body, and the same hydrophilic polyester / polyethylene composite as used in the production of the surface layer of the first absorbent body. A mixture of 50% by weight of fibers and 50% by weight of synthetic fibers having a W-shaped cross section with a fiber diameter of 4 denier and a fiber length of 51 mm made of hydrophilic polyester synthetic fibers, thickness 0.53 mm, basis weight 12 0.0 g / m ² , density 0.023
Using the back surface layer of the first absorber of g / cm ³ , the front surface layer of the first absorbent body and the back surface layer of the first absorbent body (weight ratio 1: 1) were superposed and heat-treated at 150 ° C. for 15 seconds. And melt-bonding a part of the polyethylene of the composite fiber to a thickness of 0.93 mm under a load of 12 g / cm ² and a basis weight of 24.0 g / m ² , 12
g / cm ² Average density under load 0.026 g / cm ³
The first absorber of was obtained. Next, the cotton-like pulp 200 g / m ² which was produced over the first absorbent pulp sheet fiberizer consisting of NBKP on the back layer side of the superabsorbent polymer 200 g / m ² uniformly consisting of sodium polyacrylate As shown in FIG. 3, a part of the laminated second absorbent body is wrapped with a tissue, which is a hydrophilic sheet, and is covered with a press roll having a clearance of 0.05 mm to be integrated with the first absorbent body. Got Next, a disposable diaper having the structure shown in FIGS. 1 and 2 having the absorber between the liquid-permeable top sheet and the liquid-impermeable back sheet made of polyester was prepared.

Example 2 As the first absorbent body of the absorbent body, the same hydrophilic conjugate fiber as that of the surface layer of the first absorbent body of Example 1 was used, and the thickness was 0.40 mm and the basis weight was 24.4 g. / M ² , density 0.061
A fiber layer consisting of g / cm ³ of the surface layer of the first absorbent body, 75% by weight of the same hydrophilic conjugate fiber as used in the production of the surface layer of the first absorbent body, and synthetic fiber of hydrophilic polyester. A first absorbent body having a thickness of 0.64 mm, a basis weight of 24.4 g / m ² , and a density of 0.038 g / cm ³ , which is manufactured by mixing 25% by weight of a synthetic fiber having a T-shaped cross section with a denier and a fiber length of 51 mm. Using the back surface layer of, the thickness of 1.04 mm under a load of 12 g / cm ² , the basis weight of 48.8 g / m ² , and 12 g / cm ²
A diaper was prepared for use in the same manner as in Example 1 except that the first absorber having an average density of 0.047 g / cm ³ under load was formed.

Example 3 As the first absorbent body of the absorbent body, the same hydrophilic conjugate fiber as that of the surface layer of the first absorbent body of Example 1 was used, and the thickness was 1.40 mm and the basis weight was 38.4 g. / M ² , density 0.027
A fiber layer having a surface layer of g / cm ³ of the first absorbent body, 25% by weight of the same hydrophilic conjugate fiber as used in the production of the surface layer of the first absorbent body, and a synthetic fiber of hydrophilic polyester. A first absorbent body having a thickness of 1.54 mm, a basis weight of 38.4 g / m ² , and a density of 0.025 g / cm ³ , which is manufactured by mixing 75% by weight of a synthetic fiber having a denier and a fiber length of 51 mm and having a W-shaped cross section. Using the back surface layer of, the thickness under load of 12 g / cm ^{2 is} 2.94 mm, the basis weight is 76.8 g / m ² , 12 g / cm ^2.
A diaper was prepared for use in the same manner as in Example 1 except that the first absorber having an average density of 0.026 g / cm ³ under load was formed.

Example 4 As the first absorbent body of the absorbent body, the same hydrophilic conjugate fiber as that of the surface layer of the first absorbent body of Example 1 was used, and the thickness was 0.15 mm and the basis weight was 9.7 g. / M ² , density 0.065g
/ Cm ³ of the front surface layer of the first absorbent body and the back surface layer of the first absorbent body of Example 1 manufactured using the same synthetic fiber, thickness 0.25 mm, basis weight 9.7 g / m ² , Density 0.039g
/ Cm ³ using the back surface layer of the first absorber, thickness under load of 12 g / cm ² 0.40 mm, basis weight 19.4 g /
m ^2, 12g / cm ² average density under load 0.049
A diaper was prepared by using it in the same manner as in Example 1 except that the first absorber of g / cm ³ was formed.

Example 5 The same absorber as in Example 1 was provided with NB on the back layer side of the first absorber.
200 g / m ^{2 of} cotton-like pulp prepared by defibrating a pulp sheet made of KP, 20 g / m ² of super absorbent polymer made of sodium polyacrylate, and 120 g / m of heat-fusible substance made of polyester / polyester
^As shown in FIG. 3, a part of the laminated second absorbent layer in which ² is evenly distributed is wrapped with a tissue which is a hydrophilic sheet, and is placed on a press roll with a clearance of 0.05 mm to be integrated with the first absorbent body. A diaper was prepared in the same manner as in Example 1 except that the diaper was used.

Example 6 The same absorber as in Example 1 was provided with NB on the back layer side of the first absorber.
A stack of 100 g / m ^{2 of} cotton-like pulp prepared by defibrating a pulp sheet made of KP and a second absorption layer in which 500 g / m ² of a highly absorbent polymer made of sodium polyacrylate is evenly distributed, A diaper for use as in Example 1 except that a part of the diaper was wrapped with a tissue, which was a hydrophilic sheet, and then applied to a press roll having a clearance of 0.05 mm to be integrated with the first absorbent layer as shown in FIG. Was produced.

Comparative Example 1 The first absorbent body of the absorbent body was produced by using the same hydrophilic conjugate fiber as that of the surface layer of the first absorbent body of Example 1, the thickness was 0.12 mm, and the basis weight was 10.0 g. / M ² , density 0.083
The surface layer of the first absorber of Example 1 without using the surface layer of the first absorber of g / cm ³ and the synthetic fiber having the W-shaped cross section used for the back surface layer of the first absorber of Example 1. 0.12mm thickness, basis weight 10.0g manufactured using the same synthetic fiber
0.24 m under a load of 12 g / cm ² , using the back surface layer of the first absorber having a density of 0.083 g / cm ² and a density of 0.083 g / cm ³ .
m, grammage 20.0 g / m ² , 12 g / cm ^{2 A} diaper for use was prepared in the same manner as in Example 1 except that the first absorber having an average density of 0.083 g / cm ³ under load was formed. It was made.

Comparative Example 2 As the first absorbent body of the absorbent body, 20% by weight of the same hydrophilic conjugate fiber as that of the surface layer of the first absorbent body of Example 1 and the back surface layer of the first absorbent body of Example 1 were used. A surface layer of a first absorber having a thickness of 1.11 mm, a basis weight of 10.2 g / m ² , and a density of 0.009 g / cm ³ , which is manufactured by mixing 80% by weight of the W-shaped cross-section synthetic fiber used. A synthetic fiber having the same W-shaped cross-section as that used for the surface layer of the first absorber was manufactured by using 100% by weight, and the thickness was 1.10 mm, the basis weight was 10.2 g / m ² , and the density was 0.009 g / cm. Using the back surface layer of the first absorber of ³ , 1
Thickness 2.21mm, basis weight 2 under 2g / cm ² load
Other than forming a first absorber having an average density of 0.009 g / cm ³ under a load of 0.4 g / m ² and 12 g / cm ² ,
A disposable diaper was prepared in the same manner as in Example 1.

Comparative Example 3 As the first absorbent body of the absorbent body, except that the surface layer of the first absorbent body and the back surface layer of the first absorbent body in Example 1 were reversed.
That is, a diaper was prepared for use in the same manner as in Example 1 except that the density of the surface layer of the first absorbent body was made lower than that of the back surface layer of the first absorbent body.

COMPARATIVE EXAMPLE 4 As the first absorbent body of the absorbent body, the same hydrophilic synthetic fiber as that of the surface layer of the first absorbent body of Example 1 was used, and the thickness was 0.36 mm and the basis weight was 24.4 g. / M ² , density 0.068
g / cm ³ using the same surface layer of the first absorbent body and the same fiber as the back surface layer of the first absorbent body of Example 1, thickness 0.
40 mm, basis weight 24.4 g / m ² , density 0.061 g /
with backing layer of the first absorbent cm ^3, a thickness of 0.76mm under 12 g / cm ² load, a basis weight of 48.8 g / m ^2,
Average density under load of 12 g / cm ² 0.064 g /
A diaper was prepared by using it in the same manner as in Example 1 except that the first absorber of cm ³ was formed.

Comparative Example 5 A diaper was prepared for use in the same manner as in Example 1 except that the first absorber of the absorber was not used.

Comparative Example 6 The same absorber as in Example 1 was provided with NB on the back layer side of the first absorber.
200 g / m ^{2 of} cotton-like pulp prepared by defibrating a pulp sheet made of KP, 100 g / m ^{2 of} a super absorbent polymer made of sodium polyacrylate, and 200 g / heat-fusing substance made of polyester / polyester
The second absorbent layer laminated with m ² evenly distributed is
A diaper for use as in Example 1 except that a part of the diaper was wrapped with a tissue sheet that was a hydrophilic sheet as shown in FIG. Was produced.

Comparative Example 7 A diaper for use was prepared in the same manner as in Example 1 except that the superabsorbent polymer of sodium polyacrylate as the second absorber of the absorber was not used. .

Comparative Example 8 The same absorber as in Example 1 was provided with NB on the back layer side of the first absorber.
A layer obtained by laminating a cotton-like pulp 200 g / m ² produced by subjecting a pulp sheet made of KP to a defibrating machine and a second absorption layer in which a highly absorbent polymer 1100 g / m ^{2 made} of sodium polyacrylate is evenly distributed, A diaper for use as in Example 1 except that a part of the diaper was wrapped with a tissue sheet that was a hydrophilic sheet as shown in FIG. Was produced.

The above-mentioned characteristics were evaluated using the used diapers produced in Examples 1 to 6 and Comparative Examples 1 to 8. The test results are shown in Table 1.

[Table 1]

As shown in Table 1, the characteristics of Comparative Examples 1 to 8 are considerably inferior to those of Examples 1 to 6, and the effect of the present invention was confirmed.

[0041]

As described above, by using the absorbent article of the present invention, urine, bodily fluid, loose stool, etc. in the top sheet that comes into contact with the skin of the user can be absorbed by the surface layer of the first absorbent body of the absorbent body. First, it is spot-absorbed first and passes at a high speed, and then immediately diffused in the back surface layer of the first absorber of the absorber, and further, the second absorber of the absorber absorbs the top sheet and the first absorber of the absorber. Urine, body fluids and loose stools are collected. Therefore, urine, body fluid, feces, etc. do not stagnate on the top sheet, and the dry touch property of the top sheet is significantly improved.

[Brief description of drawings]

FIG. 1 shows a partially cut-away plan view of a disposable diaper according to the present invention.

2 shows a cross-sectional view of the disposable diaper of FIG. 1 taken along the line xx ′.

3 shows an enlarged cross-sectional view of the absorber shown in FIG.

[Explanation of symbols]

1. Liquid permeable top sheet 2. Absorber 3. First absorber 3a. Surface layer of the first absorber 3b. Back layer of the first absorber 4. Second absorber 5. Liquid impermeable backsheet 6. Cotton pulp 7. Super absorbent polymer 8. Hydrophilic sheet 9. Heat fusible material 10. Stretchable elastic body 11. Tape fastener

Continuation of the front page (56) Reference JP-A-61-141361 (JP, A) JP-A-7-148876 (JP, A) JP-A-4-24026 (JP, A) JP-A-56-85401 (JP , A) JP 57-10334 (JP, A) JP 61-29351 (JP, A) JP 1-292104 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB) Name) A61F 13/15-13/84

Claims (2)

(57) [Claims] 1. An absorbent article in which an absorbent body is disposed between a liquid-permeable top sheet and a liquid-impermeable back sheet, wherein the absorbent body is in contact with the liquid-permeable top sheet. It consists of an absorber and a second absorber in contact with the liquid-impermeable back sheet, and the first absorber maintains the web form by being fused at the points where the hydrophilic synthetic fibers intersect. , And the thickness under load of 12 g / cm ² is 0.3 to
3.0 mm, an average density under load of 12 g / cm ² is 0.01 to 0.05 g / cm ³ , and the first absorber is a first absorber in contact with the liquid-permeable topsheet. Of the first absorber and the back layer of the first absorber in contact with the second absorber, the surface layer of the first absorber has a higher density than the back layer of the first absorber, The second absorbent body contains the cotton-like pulp and the superabsorbent polymer in an amount of 61% by weight or more based on the second absorbent body.
An absorbent article comprising 10 to 500 parts by weight of the superabsorbent polymer with respect to parts by weight and formed by laminating and integrating the first absorber and the second absorber. 2. The first absorbent body includes synthetic fibers having a circular cross section, and synthetic fibers having a modified cross section are provided in at least one of a surface layer of the first absorbent body and a back surface layer of the first absorbent body in each layer. 25-75 weight% is contained with respect to the absorbent article of Claim 1 characterized by the above-mentioned.