JPH09117471A - Absorbing article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve spot absorbing efficacy and dry touch property by forming a second sheet arranged between a top sheet and a absorbing material to two layers wherein the first layer of the second sheet comprises a web of synthetic fibers treated to be made hydrophilic and the cross points of which are fused and the second layer is made of cotton like pulp as a main component. SOLUTION: This absorbing article comprises a top sheet 1, a liquid impermeable back sheet 5, an absorbing material 6 arranged between the sheets 1 and 5, a second sheet 2 arranged between the top sheet 1 and the absorbing material 6 wherein the second sheet 2 comprises a body by compressing in the thickness direction and unifying a laminate of a first layer 3 and a second layer 4. The first layer 3 is made of a web of hydrophilized synthetic fibers fused at its cross points and which has a thickness of 0.3-3.0mm under the load of 12g/cm<2> and an average density of 0.01-0.05g/cm<3> and the first layer 3 has a higher density than the second side layer 4, while the second layer 4 is formed of mainly a cotton like pulp.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an absorbent article,
More specifically, the present invention relates to absorbent articles used for diapers, incontinent pads, sanitary napkins, bed sheets, pet sheets and the like.

[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.

Various proposals have been made to solve these problems, but it is proposed to provide a second sheet between the top sheet and the absorbent body in order to solve the problem that the absorption speed is lowered. There are things that have been done. For example, a net-like structural member made of a hydrophobic elastic foam (Japanese Patent Laid-Open No. 59-228001), a sheet made of a hydrophilic synthetic fiber and a hot-melt fiber (Japanese Patent Laid-Open No. 60-19815).
No. 2), a fiber aggregate layer in which each fiber is fused at an intersection to maintain a web form (Japanese Patent Laid-Open No. 62-276003), a first phase in an unlofted state and a lofted state. Second in
It has been proposed to use a sheet made of a particle-bonded non-woven material having a phase (2) (Japanese Patent Laid-Open No. 63-220867) as a second sheet. However, although the second sheet made of these synthetic fibers has a high absorption rate, it does not have the ability to absorb the liquid on the top sheet, so that urine, body fluid and loose feces remain on the top sheet, and the dry touch property of the top sheet is not good. It has the drawback of.
Deterioration of dry touch may cause discomfort to the user, and may cause skin irritation in the case of infants.

A method of changing the superabsorbent polymer inside the absorbent body in order to quickly absorb the urine of the wearer (Japanese Patent Laid-Open Publication No. Sho 6-62).
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.

Further, the density of the upper flocculent pulp is lowered as much as possible to 0.08 to 0.1 g / cm ³ by making the top liquid permeable top sheet as hydrophilic as possible, making it thin, or providing pores. It is known to adjust or to make the surface properties of cotton-like pulp as hydrophilic as possible. Further, in order to reduce the wet-back, the method for making the porous liquid-permeable sheet as hydrophobic as possible or having a certain thickness, and for accelerating the diffusion of the liquid in the layer of the cotton-like pulp is carried out. Cage,
Specifically, it has been proposed to dispose a perforated partition layer between fluff pulps (JP-A-61-186505). Further, the perforated structure is disposed between the top sheet and the back sheet (Japanese Patent Laid-Open No. 60-253447),
The density of the upper flocculent pulp is 0.03 to 0.07 g / cm ^3.
(Japanese Patent Application Laid-Open No. 56-85401) and the like have been proposed, but these methods are effective for urine and body fluid, but cannot absorb loose loose feces with high viscosity. Further, a method for isolating feces by changing the structure of a diaper is disclosed (Japanese Patent Laid-Open No. 4-30054).
No. 3). 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.

[0006]

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 stool into the absorber, An object is to provide an absorbent article in which the dry touch property of the top sheet is remarkably improved.

[0008]

SUMMARY OF THE INVENTION The present invention is directed to a liquid-permeable top sheet, a liquid-impermeable back sheet, an absorber disposed between the sheets, and the top sheet and absorbent sheet. In an absorbent article having a second sheet arranged between the body, the second sheet comprises a first second sheet in contact with the top sheet, and a second second sheet in contact with the absorber, and the first second sheet. And a second second sheet are laminated and compressed in the thickness direction to be integrally formed, and the first second sheet is fused and bonded at a point where the hydrophilized synthetic fibers intersect. The morphology is maintained, the thickness under load of 12 g / cm ² is 0.3 to 3.0 mm, and the average density under load of 12 g / cm ² is 0.01 to 0.05 g / cm ^3.
The surface layer of the first second sheet in contact with the top sheet, and the back surface layer of the first second sheet located below the surface layer, and the surface layer is more dense than the back surface layer. The second second sheet is composed mainly of cotton-like pulp, and is 30 to 70 relative to the length of the absorbent core with the longitudinal edge of the back body portion of the absorbent core as a base point. % Of the absorbent article. Further, the present invention provides
The first second sheet includes synthetic fibers having a circular cross section, and further includes at least one of a front surface layer of the first second sheet and a back surface layer of the first second sheet having a modified cross section fiber in an amount of 25 to 75% by weight with respect to each layer. It exists in the absorbent article characterized by the above.

The absorbent article of the present invention has an absorbent body between the liquid-permeable top sheet and the liquid-impermeable back sheet, and has a second layer between the liquid-permeable top sheet and the absorbent body. It has a sheet. In the present invention, the second sheet is composed of a first second sheet in contact with the liquid-permeable top sheet and a second second sheet in contact with the absorber, and the second second sheet is arranged in the rear body part of the absorber. Further, the first second sheet is composed of a surface layer of the first second sheet in contact with the liquid-permeable top sheet and a back surface layer of the first second sheet located below the surface layer. The surface layer has a higher density than the back surface layer of the first second sheet. In addition, the second second sheet is mainly composed of cotton-like pulp, and further, the second second sheet has an edge of the absorbent body in the longitudinal direction of the rear body part as a base point and is 30 with respect to the length of the absorbent body. It is arranged at a position of 70%.

In the absorbent article of the present invention having the above-mentioned structure, the back surface of the liquid permeable top sheet is in contact with the dense portion of the first second sheet, and the front body portion of the absorbent body is covered with the front body portion. , The low-density part of the first second sheet is in contact, so urine and body fluids in the top sheet,
It is first spot-absorbed by the front surface layer of the first second sheet and passes through at a high speed, and then immediately diffused by the back surface layer of the first second sheet to reach the absorber. Further, since the second second sheet containing cotton-like pulp as a main component is arranged on the surface of the rear body part of the absorbent body, soft stools and diarrhea stools excreted by the wearer are separated between the fibers of the cotton-like pulp layer. Absorbed in voids,
Hold and be released. Since loose stools and diarrhea stools have higher viscosity and less water than urine, a layer made of cotton-like pulp that holds solids in voids between fibers is arranged rather than a highly absorbent polymer that absorbs water. There is a need. Then, the back surface of the liquid-permeable top sheet is in contact with the high density portion of the first second sheet, and the surface of the second second sheet is in contact with the low density portion of the first second sheet, so that the top Soft stools etc. in the sheet are quickly spot-absorbed by the surface layer of the first second sheet and pass at a high speed, then immediately diffused in the back surface layer of the first second sheet, and further as a top sheet in the second sheet. The loose stool etc. of the first second sheet is taken up and reaches the absorber.

Therefore, soft feces with high viscosity from the liquid-permeable top sheet can be quickly absorbed, and then the liquid can be rapidly diffused and released to be transferred to the absorber.
Therefore, loose stools rarely remain on the top sheet, the amount of wet back that soft stools return to the top sheet is reduced, and, as described above, since loose stools do not remain on the top sheet, the skin touches the human body. Also, it does not have a feeling of getting wet, has excellent dry touch properties, and gives an unpleasant feeling to the user, and the problem of skin irritation of the human body is improved. By making the front body and back body of the second seat suitable for urine or loose stools, the wearer's urine, body fluids, loose stools and diarrhea can be quickly absorbed and isolated and retained. Therefore, it is possible to shorten the contact time of excrement with the skin that causes dermatitis. 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.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the absorbent article of the present invention will be described in detail with reference to the drawings, taking a disposable diaper as an example, but the present invention is not limited to these.

FIG. 1 is a plan view showing a state in which the diaper is unfolded by using it. As shown in FIG. 1, the disposable diaper is composed of a liquid-permeable top sheet 1 and a second sheet 2.
And liquid impermeable back sheet 5 and second sheet 2
And an absorbent body 6 disposed between the liquid impermeable back sheet 5. FIG. 2 is a vertical cross-sectional view of the disposable diaper shown in FIG. 1 taken along the line YY '. As shown in FIG. 2, the disposable diaper has an absorbent body 6 disposed between a liquid-permeable top sheet 1 and a liquid-impermeable back sheet 5, and a liquid-permeable top sheet. The second sheet 2 is disposed between the absorbent core 1 and the absorber 6. The second sheet 2 is composed of a first second sheet 3 in contact with the liquid-permeable top sheet 1 and a second second sheet 4 in contact with the absorber. FIG. 3 shows an enlarged cross-sectional view of the second seat 2 when cut along the line XX ′ in FIG. The first second sheet 3 comprises a surface layer 3a of the first second sheet which is in contact with the liquid permeable top sheet 1 and a back surface layer 3b of the first second sheet which is located below the surface layer 3a. The surface layer 3a of the sheet has a higher density than the back surface layer 3b of the first second sheet. The second second sheet 4 contains cotton-like pulp as a main component. Further, the second second seat 4 is arranged in the rear body part of the absorber 6.

In the disposable diaper having such a structure, the back surface of the liquid-permeable top sheet is in contact with the high density portion of the first second sheet, and the front body portion of the absorbent body has Since the low-density part of one second sheet is in contact, urine, body fluid, etc. in the top sheet are spot-absorbed quickly by the surface layer of the first second sheet and pass through at a high speed, then the back surface of the first second sheet. The layers diffuse immediately and reach the absorber. Further, since the second second sheet containing cotton-like pulp as a main component is arranged on the surface of the rear body part of the absorbent body, soft stools and diarrhea stools excreted by the wearer are separated between the fibers of the cotton-like pulp layer. It is absorbed, retained, and released in the void. Soft stools and diarrhea stools have higher viscosity and less water than urine, which is mostly water, so they are made from cotton-like pulp that holds solids in voids between fibers rather than superabsorbent polymers that absorb water. It is necessary to arrange the layers. Then, the back surface of the liquid-permeable top sheet is in contact with the high density portion of the first second sheet, and the surface of the second second sheet is in contact with the low density portion of the first second sheet, so that the top Soft stools etc. in the sheet are quickly spot-absorbed by the surface layer of the first second sheet and pass at a high speed, then immediately diffused in the back surface layer of the first second sheet, and further as a top sheet in the second sheet. The loose stool etc. of the first second sheet is taken up and reaches the absorber.

Therefore, soft feces with high viscosity from the liquid-permeable top sheet can be quickly absorbed, and then the liquid can be rapidly diffused and released to be transferred to the absorber.
Therefore, loose stools rarely remain on the top sheet, the amount of wet back that soft stools return to the top sheet is reduced, and, as described above, since loose stools do not remain on the top sheet, the skin touches the human body. Also, it does not have a feeling of getting wet, has excellent dry touch properties, and gives an unpleasant feeling to the user, and the problem of skin irritation of the human body is improved. By making the front body and back body of the second seat suitable for urine or loose stools, the wearer's urine, body fluids, loose stools and diarrhea can be quickly absorbed and isolated and retained. Therefore, it is possible to shorten the contact time of excrement with the skin that causes dermatitis. Therefore, urine, body fluids and loose stools hardly remain on the top sheet,
The amount of wet back that returns to the top sheet is small, and since soft stool does not remain on the top sheet, there is no wet feeling even if it touches the skin of the human body, dry touch is excellent, and it causes discomfort to the user. The problem of skin irritation is also improved.

The materials constituting the disposable diaper of the present invention will be described below. Liquid permeable topsheet The liquid permeable topsheet used is nonwoven fabric, woven fabric,
Liquid permeable sheets such as mesh sheets, porous foams, and porous films. 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.

Second Sheet The second sheet comprises a first second sheet which contacts the liquid permeable top sheet and a second second sheet which contacts the absorber, and the first second sheet contacts the liquid permeable top sheet. It is composed of a surface layer of one second sheet and a back surface layer of the first second sheet located below the surface layer. The first second sheet maintains a web form by being fused at the points where the hydrophilized synthetic fibers intersect, and has a thickness of 0.3 under a load of 12 g / cm ^2.
In ～3.0Mm, an average density of 0.01 to 0.05 g / cm ³ at 12 g / cm ² weight under further towards the surface layer of the first second sheet in contact with the liquid-permeable top sheet However, the density is higher than that of the back surface layer of the first second sheet located below the front surface layer. When the average density of the first second sheet exceeds 0.05 g / cm ³ ,
Not suitable due to reduced absorption rate. Also, 0.0
If the amount is less than 1 g / cm ³ , the density of the surface layer of the first second sheet is reduced, and urine, bodily fluid and loose stool cannot be quickly absorbed from the top sheet, and the sheet easily leaks. Also, when the thickness of the first second sheet under a load of 12 g / cm ² exceeds 3.0 mm and becomes thick,
From the top sheet, urine, body fluids and loose stools cannot be quickly absorbed by the absorbent body, and leaks easily. Also, 0.3 mm
If it is less than 1, it is not suitable because the absorption rate decreases.

In the present invention, the synthetic fiber used in the first second sheet 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 fibers are preferred from the viewpoint of strength. Further, the fiber diameter is 1.5 to 10 denier, and the length is 10 to 10
About 0 mm is preferable in terms of manufacturing. As a method for hydrophilizing these fibers and conjugate fibers, there is a method of applying a hydrophilizing agent to the fibers and conjugate fibers by spraying, or a method of treating the produced first second sheet by spray application, foam coating, impregnation, etc. is there.

Further, in the present invention, the first second sheet contains a synthetic fiber having a circular cross section, and further, at least one of the front surface layer of the first second sheet and the back surface layer of the first second sheet. 25 to 75% by weight of modified cross-section fibers having various cross-sectional shapes are contained in each layer. In this case, the back surface layer of the first second sheet preferably contains more modified cross-section fibers than the front surface layer of the first second sheet, and more preferably contains only the back surface layer of the first second sheet. By containing more modified cross-section fibers in the back surface layer of the first second sheet, the back surface layer of the first second sheet has a lower density than the front surface layer of the first second sheet. For this reason, for example, in the case of the same denier, since the modified cross-section fiber has a larger cross-sectional area than the circular cross-section fiber, the density becomes low when the modified cross-section fiber is included. There is also a method in which the fiber diameter of the modified cross-section fiber is larger than that of the circular cross-section fiber. When the content of the modified cross-section fiber in each layer is less than 25% by weight, the absorption rate is decreased, which is not suitable. Further, when the content of the modified cross-section fiber in each layer exceeds 75% by weight, the density of the surface layer of the first second sheet becomes small, and the top sheet cannot quickly absorb urine, body fluid and loose feces. , Leaks easily. Examples of the modified cross-section fiber include polypropylene, polyethylene, polyester, acrylic resin, nylon resin, etc.
Shapes, W-shapes, H-shapes, rhombuses, amoeber shapes and the like are preferable, but are not particularly limited.

The cotton-like pulp used in the second second sheet of the present invention has a fiber length of 5 mm or less obtained by defibrating a chemical pulp sheet or a mechanical pulp sheet with a pulverizer. Further, a crosslinking agent may be added to the fiber, and the fiber may be subjected to mechanical stirring, fluffing, and heat treatment to have a fiber having an intrafiber cross-linking bond, which is deformed and fixed. As pulp raw materials, wood pulp such as softwood and hardwood, and non-wood pulp such as hemp are also applied. The amount of pulp used may be a single one or a mixture of two or more depending on the intended second sheet.

As a method for manufacturing the second sheet, first, webs having different densities are stacked so that the surface layer of the first second sheet has a higher density than the back surface layer of the first second sheet, and heat is applied. Are integrated with each other to produce the first second sheet. In order to integrate the front surface layer of the first second sheet and the back surface layer of the first second sheet, two types of webs forming both layers are superposed, and the fibers are fused into one layer by heat treatment. 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. It can also be carried out by a heat treatment method in which a low density layer is formed by applying a low temperature.

Then, a cotton-like pulp to be the second second sheet is laminated on the back layer side of the obtained first second sheet, and then compressed and integrated. The lamination method is formed by a conventional method such as air forming, but is not particularly limited. The second second sheet is arranged at a position of 30 to 70% with respect to the length of the absorbent body, with the longitudinal end edge of the rear body portion of the absorbent body as a base point. When the second second sheet is arranged in the front body part where the ratio of the length of the absorbent body to the longitudinal direction is more than 70% from the edge of the back body part, the urine and body fluid of the top sheet are quickly absorbed and diffused. However, it becomes difficult for the absorbent body to absorb and retain them, and the residual amount of the top sheet increases, resulting in poor dry touch properties, which is not preferable. Further, when the ratio of the length to the longitudinal direction of the absorbent body is arranged only in the region of the rear body part from the edge of the rear body part being more than 30%, the loose stool of the top sheet cannot be taken into the second sheet, The amount of residual topsheet increases, resulting in poor dry touch.
Not preferred.

The basis weight of the cotton-like pulp to be laminated is 1
0-250g / m^Two Is appropriate. Cotton pulp basis weight
But 250g / m^Two If you go over the second seat
Urine, body fluids, loose stools, etc. may accumulate and not reach the absorber.
And the effect on the wet back can no longer be seen,
Not appropriate. The basis weight of the cotton-like pulp is 10 g / m.
^Two If it is less than the maximum, urine, body fluids and loose stools on the top sheet are removed.
I can't take it to the cand seat,
A large amount of residue is left, resulting in poor dry touch.
It is not preferable. As a compression method, press roll
Although the compression is performed with advantage, rolls with a smooth peripheral surface, etc.
Ensures that the density of the second second seat is
A continuous planar surface that is substantially even,
It may be embossed with a roll having an uneven surface.
The second second sheet has a partially different density.
And guides urine, body fluids and loose stools vertically and diagonally.
It may be a similar arrangement. For embossing, the compression part,
The non-compression portion may be continuous or non-continuous.

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

Absorber The known absorber can be applied as it is,
For example, the most general-purpose one can be used in which the cotton-like pulp and the superabsorbent polymer are uniformly mixed, and the mixture is wrapped with a hydrophilic sheet. In this case, 3 to 60% by weight of the heat-fusible substance may be mixed with the cotton-like pulp and thermocompression bonded. The cotton-like pulp has a fiber length of 5 mm or less, which is 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 the pulp used varies depending on the intended absorber, for example, it is used alone, a plurality of layers are used, or another absorbent is used in combination, but generally 50 to 400 g / It is in m ^2.

As the superabsorbent polymer, starch type,
Cellulose type and synthetic polymer type are mentioned. That is, a starch-acrylic acid (salt) graft copolymer, a saponified product of a starch-ethyl acrylate graft copolymer, a saponified product of a starch-methyl methacrylate acid graft copolymer, a saponified product of a 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. The application 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 dried cotton-like pulp, and such an amount of the superabsorbent polymer is substantially contained in the cotton-like pulp. Are evenly distributed over 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 heat-fusible substance is preferably fibrous 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, 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 air dryer, a microwave heater, an infrared heater, etc., but the heat is evenly transferred to the mat layer, and the heat fusible substance melts to form a skeletal structure. It is good if it can be formed.

The hydrophilic sheet may be a hydrophilic sheet such as tissue, absorbent paper, hydrophilic non-woven fabric or the like. As a method of compressing the absorber, a continuous surface may be used so that the density of the absorber is substantially uniform by a roll having a smooth peripheral surface, or the peripheral surface may be uneven. The density of the absorbent body may partially differ depending on the roll or the like, and the embossing may be a pattern arrangement that guides urine or body fluid in the vertical and diagonal directions. In the case of embossing, the compressed part and the non-compressed part may be continuous or discontinuous.

Liquid-impermeable backsheet The backsheet used is a material obtained by laminating a liquid-impermeable film such as polyethylene 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.

The members described above are, for example, a liquid-permeable top sheet and a second sheet, a second sheet and an absorbent body, and a space between the absorbent body and a liquid-impermeable back sheet.
Adhesion such as hot melt adhesion is performed on all or part of the surface. As an adhesive, starch-based or CMC
A water-soluble paste such as (carboxymethyl cellulose) or a highly fluid adhesive may be used. In the disposable diaper (absorbent article) of the present invention, the effect of the present invention can be achieved only by combining the above-described top sheet, second sheet and absorber.

[0031]

The effects of the present invention will be described below in detail 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 after using the diaper for which the absorption rate was measured (absorbing 50 cc three times) for 30 minutes, the filter paper of 10 × 10 cm square (made by Toyo Roshi Kaisha, No. 63) was used 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 the hand and its 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 criterion ○: dry △: moist ×: considerably moist 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 Liquid Permeable Top Sheet As the hydrophilic fiber, a composite fiber of polyester / polyethylene having a fiber diameter of 2 denier and a fiber length of 51 mm, which was hydrophilized by spray coating, was used, and the basis weight was 25.0.
A top sheet having a liquid permeability of g / m ² was obtained.

Second sheet As the first second sheet, it is made hydrophilic by spray coating.
Treated hydrophilic polyester / polyethylene composite
A circular fiber with a diameter of 2 denier and a fiber length of 51 mm
0.40 mm thick, basis weight manufactured using cross-section fibers
12.0 g / m ^Two, Density 0.030 g / cm^ThreeFirst seca
Of the surface layer of the second sheet and the surface layer of the first second sheet
The same hydrophilic polyester / polyethylene used for manufacturing
50% by weight of ren composite fiber, and hydrophilic polyester
Fiber diameter 4 denier, fiber length 51mm
Thickness produced by mixing 50% by weight of W-shaped cross-section fiber
0.53 mm, basis weight 12.0 g / m^Two , Density 0.023
g / cm^ThreeUsing the backside layer of the first second sheet of
Front sheet layer of the second sheet and back layer of the first second sheet
(Weight ratio of 1: 1) is overlaid and heated at 150 ° C for 15 seconds.
Heat treatment to melt-bond part of the polyethylene in the composite fiber
12g / cm^Two Thickness under load 0.93 mm,
Basis weight 24.0 g / m^Two , 12 g / cm^Two Under load
Average density 0.026g / cm^ThreeThe first second seat of
Obtained. Next, use a pulp sheet made of NBKP in a defibrator.
Using the cotton-like pulp produced by the
50 g / m 2 on the back side of the base^TwoStacked so that
To form the second second sheet, and the second second sheet
From the edge of the back part of the absorber to the longitudinal direction of the absorber.
The ratio to the length is 50% from the edge of the back body.
The press row with a clearance of 0.05 mm.
The second seat is integrated with the first second seat
I got it.

The absorbent cotton-like pulp 200 g / m ^2, heat consists superabsorbent polymer 200 g / m ^2, and polyester / polyester consisting of sodium polyacrylate fusible substance 20 g /
Wrap uniformly in m ² and wrap it in tissue, and use a heat press roll with a surface temperature of 150 ° C to obtain a total tightness of 0.1.
It was adjusted to be 0 g / m ³ to obtain an absorber. Next, the absorbent sheet is provided between the liquid-permeable top sheet and the liquid-impermeable back sheet made of polyester, and the second sheet is provided between the liquid-permeable top sheet and the absorbent body. A disposable diaper having the structure shown in FIGS. 1 and 2 was prepared.

Example 2 The same hydrophilic composite fiber as the surface layer of the first second sheet of Example 1 was used as the first second sheet, and the thickness was 0.40 mm and the basis weight was 24.4 g / m ^2. , A surface layer of the first second sheet having a density of 0.061 g / cm ³ , and 75% by weight of the same hydrophilic conjugate fiber as used in the production of the surface layer of the first second sheet, and a fiber of hydrophilic polyester. Fiber diameter 4 denier, fiber length 51m
25% by weight of T-shaped cross-section fiber having a thickness of 0.64 mm, a basis weight of 24.4 g / m ² , and a density of 0.03.
Using the backside layer of the first second sheet of 8 g / cm ³ , 1
Thickness under load of ² g / cm ² 1.04 mm, basis weight 4
A diaper was prepared for use in the same manner as in Example 1 except that the first second sheet having an average density of 0.047 g / cm ³ under a load of 8.8 g / m ² and 12 g / cm ² was formed.

Example 3 The same hydrophilic composite fiber as the surface layer of the first second sheet of Example 1 was used as the first second sheet, and the thickness was 1.40 mm and the basis weight was 38.4 g / m ^2. , A surface layer of the first second sheet having a density of 0.027 g / cm ³ , 25% by weight of the same hydrophilic conjugate fiber as used in the production of the surface layer of the first second sheet, and a fiber of hydrophilic polyester. Fiber diameter 4 denier, fiber length 51m
m W-shaped cross-section fiber of 75 wt% was mixed and produced, thickness 1.54 mm, basis weight 38.4 g / m ² , density 0.02
Using the backside layer of the first second sheet of 5 g / cm ³ , 1
Thickness under load of ² g / cm ² 2.94 mm, basis weight 7
Except that the ^{6.8g / m 2, 12g / cm} 2 under a load to form a first second sheet of the average density of 0.026 g / cm ^3, the same procedure as in Example 1 to prepare a disposable diaper.

Example 4 The same hydrophilic composite fiber as the surface layer of the first second sheet of Example 1 was used as the first second sheet, and the thickness was 0.15 mm and the basis weight was 9.7 g / m ^2. , Density 0.
A thickness of 0.25 mm and a basis weight of 9.7 g / m, which were produced by using the same fiber as the surface layer of the first second sheet of 065 g / cm ³ and the back layer of the first second sheet of Example 1.
^2, using a backside layer of the first second sheet of density 0.039 g / cm ^3, a thickness of under 12 g / cm ² load 0.
A disposable diaper was prepared in the same manner as in Example 1 except that a first second sheet having a weight of 40 mm, a basis weight of 19.4 g / m ² , and an average density of 0.049 g / cm ³ under a load of 12 g / cm ² was formed. It was made.

Example 5 From the edge of the rear body part of the absorbent body, the second second sheet was
A diaper for use was prepared in the same manner as in Example 1 except that the absorbent body was arranged such that the ratio of the length of the absorbent body to the longitudinal direction was 70% from the edge of the back body.

Example 6 From the edge of the back body of the absorbent body, the second second sheet was
A diaper for use was prepared in the same manner as in Example 1 except that the absorbent body was arranged such that the length ratio of the absorbent body to the longitudinal direction was 30% from the edge of the back body.

Comparative Example 1 As the first second sheet, the first second sheet of Example 1 was used.
Manufactured using the same hydrophilic composite fibers as the surface layer
In addition, thickness 0.12mm, basis weight 10.0g / m^Two ,density
0.083 g / cm^ThreeSurface layer of the first second sheet of
And used for the back layer of the first second sheet of Example 1.
The first second of Example 1 without the use of W-shaped cross-section fibers
Thickness produced using the same fibers as the surface layer of the sheet
0.12 mm, basis weight 10.0 g / m^Two , Density 0.083
g / cm^ThreeUsing the backside layer of the first second sheet of
g / cm^Two Thickness under load 0.24mm, basis weight 2
0.0 g / m ^Two , 12 g / cm^Two Average density under load
Degree 0.083g / cm^ThreeForming the first second sheet of
A disposable diaper was made in the same manner as in Example 1 except that
Made.

Comparative Example 2 As the first second sheet, 20% by weight of the same hydrophilized conjugate fiber as the surface layer of the first second sheet of Example 1 and W used in the back layer of the first second sheet of Example 1 were used.
Thickness 1.1 produced by mixing 80% by weight of mold cross-section fibers
1 mm, basis weight 10.2 g / m ² , density 0.009 g / c
m ³ of the surface layer of the first second sheet and the same W-shaped cross-section fiber as that used for the surface layer of the first second sheet 100
Produced using weight%, thickness 1.10 mm, basis weight 1
Using the backside layer of the first second sheet having a density of 0.2 g / m ² and a density of 0.009 g / cm ^3, a thickness of 2.21 mm under a load of 12 g / cm ² and a basis weight of 20.4 g / m ² , 12 g
/ Cm ² Average density under load 0.009 g / cm ³
A diaper was prepared by using it in the same manner as in Example 1 except that the first second sheet of 1 was formed.

Comparative Example 3 As the first second sheet, the first second sheet was made to have a front layer and a back layer of the first second sheet which were opposite to each other in the first example, that is, the first second sheet had a back layer first. A diaper was prepared for use in the same manner as in Example 1 except that the surface layer of the second sheet had a lower density.

Comparative Example 4 The same hydrophilic fiber as that of the surface layer of the first second sheet of Example 1 was used as the first second sheet, and the thickness was 0.36 mm and the basis weight was 24.4 g / m ² . Density 0.06
A thickness of 0.40 mm, a basis weight of 24.4 g / m ² , produced using the same fibers as the surface layer of the first second sheet of 8 g / cm ³ and the back layer of the first second sheet of Example 1.
Using the back surface layer of the first second sheet having a density of 0.061 g / cm ^3, a thickness of 0.76 under a load of 12 g / cm ^2.
mm, basis weight 48.8 g / m ² , 12 g / cm ^{2 A} diaper for use was prepared in the same manner as in Example 1 except that a first second sheet having an average density of 0.064 g / cm ³ under a load was formed. It was made.

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

Comparative Example 6 A second second sheet was placed from the edge of the back body of the absorbent body,
A diaper for use was prepared in the same manner as in Example 1 except that the absorbent body was arranged such that the length ratio of the absorbent body to the longitudinal direction was 20% from the end edge of the back body.

Comparative Example 7 A second second sheet was placed from the edge of the back body of the absorbent body,
A diaper for use was prepared in the same manner as in Example 1 except that the absorbent body was arranged such that the length ratio of the absorbent body to the longitudinal direction was 80% from the end edge of the back body. The above-mentioned characteristics were evaluated using the used diapers produced in Examples 1 to 6 and Comparative Examples 1 to 7 described above. Table 1 shows the test results.

[0047]

[Table 1]

As shown in Table 1, the characteristics of Comparative Examples 1 to 7 are considerably inferior to those of Examples 1 to 6, and the effect of the present invention was confirmed.

[0049]

As described above, by using the absorbent article of the present invention, urine, body fluids, loose stools and the like in the top sheet that comes into contact with the user's skin are spotted on the surface layer of the first second sheet as soon as possible. It is absorbed and passes at a high speed, then immediately diffused in the back surface layer of the first second sheet, and urine, body fluid and the like in the front body portion reach the absorber. Further, in the rear body part, the liquid permeable top sheet and the soft feces of the first second sheet are taken up by the second second sheet and reach the absorber. By making the front body and back body of the second seat suitable for urine, body fluid or loose stool, the wearer's urine, body fluid and loose stool or diarrhea can be quickly absorbed, isolated and retained. It is possible to shorten the contact time of excrement with the skin that causes dermatitis. 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 the drawings]

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

FIG. 2 is a vertical sectional view of the disposable diaper of FIG. 1 taken along line YY ′.

FIG. 3 shows the second sheet of the disposable diaper shown in FIG.
The enlarged cross-sectional view cut by -X 'is shown.

[Explanation of symbols]

 1. 1. Liquid permeable topsheet Second seat 3. First second seat 3a. Surface layer of first second sheet 3b. Back layer of the first second sheet 4. Second second seat 5. Liquid-impermeable backsheet 6. Absorber 7. Fluffy pulp 8. Super absorbent polymer 9. Hydrophilic sheet 10. Heat-fusible substance 11. Stretchable elastic body 12. Tape fastener

Claims (2)

[Claims] 1. A liquid-permeable top sheet, a liquid-impermeable back sheet, an absorber arranged between the two sheets, and a second sheet arranged between the top sheet and the absorber. In the absorbent article having, the second sheet is composed of a first second sheet in contact with the top sheet, and a second second sheet in contact with the absorber, and a laminate of the first and second second sheets. The first second sheet is formed by compressing in the thickness direction and is integrated, and the first second sheet is fused at a point where the hydrophilized synthetic fibers intersect to maintain a web shape, and is 12 g / cm ^2. The thickness under load is 0.3-3.
0 mm, the average density under load of 12 g / cm ² is 0.01 to 0.05 g / cm ³ , and further, it is located below the surface layer of the first second sheet in contact with the top sheet. It is composed of a back surface layer of the first second sheet, and the surface layer has a higher density than the back surface layer, the second second sheet is composed mainly of cotton-like pulp, and the absorber Based on the longitudinal edge of the back body, the length of the absorber is 30 to 7
An absorbent article, which is arranged at 0% position. 2. The first second sheet includes synthetic fibers having a circular cross section, and further, at least one of the surface layer of the first second sheet and the back surface layer of the first second sheet has a modified cross section fiber for each layer. The absorbent article according to claim 1, wherein the absorbent article contains ˜75% by weight.