JPH0956748A - Absorptive article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an absorptive article which can absorb urine, body liquid and soft feces quickly, reduce liquid that returns and/or remains on a top sheet, and is free of stickiness and leakage. SOLUTION: A second sheet is constituted of a first layer in contact with a liquid-permeable top sheet, and a second layer in contact with an absorbing body. The first layer of the second sheet maintains a web form being bonded to points where hydrophilic synthetic fibers intersect, whereas its thickness is from 0.3 to 3.0mm under pressurization of 12g/cm<2> , and its average density is from 0.01 to 0.05g/cm<3> under pressurization of 12g/cm<2> . The surface layer of the first layer in contact with the permeative top sheet has higher density than the rear surface of the first layer in contact with the second layer of the second sheet, and the second layer of the second sheet is made of cotton-like pulp as the main component. The second sheet is formed by integrating the lamination of the first layer of the second sheet and the second layer of the second sheet.

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 type of absorbent article, include a cotton-like pulp, a superabsorbent polymer, a hydrophilic polymer, and a hydrophilic sheet between a liquid-permeable top sheet and a liquid-impermeable back sheet. It has a configuration in which an absorbent body made of a 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.

Further, pulp fibers have been conventionally used as an absorbent member. This is because the pulp fiber has a high water retention capacity and a low absorption liquid release performance. However, such a property of the pulp fiber has a problem that the absorption rate becomes slower when it is repeatedly absorbed, and therefore it is not used in the second sheet which is required to have the liquid discharging performance. In addition, since cellulose fibers are not rigid, they have a low compression recovery property, and even if they are released from a pressurized state, the thickness of the sheet does not return, and the tightness remains high, so the absorption rate decreases. There is also. In order to solve the problem of compression recovery of these pulp fibers, a production method of crosslinking the inside of the cellulose fibers has been disclosed (JP-A-5-71702, JP-A-3-206174, JP-A-3-206175). Japanese Laid-Open Patent Publication No. 3-205
176). Since the cross-linked fibers in the cellulose fibers have improved compression recovery properties, when used as an absorbent member, the absorption rate can be increased. However, when it is used as a second sheet, the liquid absorbability and the liquid discharge property are not sufficient.

In order to quickly absorb the urine and body fluid of the user, the top liquid-permeable top sheet is made as hydrophilic as possible, thinned, or provided with pores, and the density of the upper flocculent pulp is lowered as much as possible. 0.08-0.1
It is known that the surface property of the cotton-like pulp is made as hydrophilic as possible by adjusting it to g / cm ³ . 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. Therefore, specifically, it has been proposed to dispose a perforated partition layer between fluff pulps (JP-A-61-186505). Further, the perforated structure is arranged between the top sheet and the back sheet (JP-A-60-253447), and the density of the upper flocculent pulp is reduced to 0.03 to 0.07 g / cm ³ (see (Kaisho 56-85401 gazette) is proposed,
Although these methods are effective for urine and body fluids, they cannot absorb soft feces with high viscosity. In addition, a top sheet having an opening is provided to isolate and hold feces (Japanese Patent Laid-Open No. 4-300543), but the opening is crushed when the user is sitting and the feces do not enter. However, in practice, it has the drawback that it does not move and leaks.

[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]

According to the present invention, an absorbent body is disposed between a liquid-permeable top sheet and a liquid-impermeable back sheet, and the absorbent body is placed between the liquid-permeable top sheet and the absorbent body. In an absorbent article in which a second sheet is arranged, the second sheet is composed of a second layer of the second sheet in contact with the liquid-permeable top sheet and a second layer of the second sheet in contact with the absorber. The first layer of the sheet is fused at the intersection of the hydrophilic synthetic fibers to maintain the web form and has a thickness of 0.3 to 3.0 mm under a load of 12 g / cm ² and a thickness of 12 g / cm ^2. The average density under the load of cm ² is 0.01 to 0.05 g / cm ³
Further, the surface layer of the first layer in contact with the liquid-permeable top sheet has a higher density than the back surface layer of the first layer in contact with the second layer of the second sheet, and The second layer is composed of cotton-like pulp as a main component, and is formed by laminating a first layer of the second sheet and a second layer of the second sheet, and the second layer is in an absorbent article. Furthermore, the present invention provides that the first layer of the second sheet contains synthetic fibers having a circular cross section, and further has modified cross section fibers in at least one of the front layer of the first layer and the back layer of the first layer 25 for each layer. It exists in the absorbent article characterized by including -75weight%.

The absorbent article of the present invention has an absorbent body between a liquid-permeable top sheet and a liquid-impermeable back sheet, and has a second sheet between the liquid-permeable top sheet and the absorbent body. It is a thing. In the present invention, the second sheet is composed of a first layer of the second sheet in contact with the liquid-permeable top sheet and a second layer of the second sheet in contact with the absorber, and the first layer of the second sheet is a liquid. It is composed of a surface layer of the first layer in contact with the permeable top sheet and a back layer of the first layer in contact with the second layer of the second sheet, and the surface layer of the first layer is more dense than the back layer of the first layer. Is high. Also, the second layer of the second seat,
It is composed mainly of cotton-like pulp. 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 layer of the second sheet is in contact, the surface of the second layer of the second sheet is ,
Since the low-density portion of the first layer of the second sheet is in contact, urine, body fluids, loose stools, etc. in the top sheet,
It is quickly absorbed by the first layer of the surface layer and passes at a high speed, and then immediately diffused by the back layer of the first layer,
Further, the second layer of the second sheet takes up the top sheet and the first layer of the second sheet to collect urine, body fluid, loose stool, etc., and reach the 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.

[0010]

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, a disposable diaper is composed of a liquid-permeable top sheet 1 and a second sheet 2
And a liquid impermeable back sheet 5 and a second sheet 2
And an absorbent body 6 disposed between the 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 an absorbent body 6 disposed between a liquid-permeable top sheet 1 and a liquid-impermeable back sheet 5, and the liquid-permeable top sheet 1 and the absorbent body 6 are absorbed. The second seat 2 is arranged between the bodies 6. The second sheet 2 is composed of a second sheet first layer 3 in contact with the liquid-permeable top sheet 1 and a second sheet second layer 4 in contact with the absorber. FIG. 3 shows an enlarged cross-sectional view of the second seat 2 shown in FIG. Second sheet first layer 3
Consists of a first surface layer 3a in contact with the liquid permeable top sheet 1 and a first back surface layer 3b in contact with the second layer 4 of the second sheet. The first surface layer 3a is The density is higher than that of the back surface layer 3b of the first layer. The second layer 4 of the second sheet is composed mainly of cotton-like pulp. The disposable diaper having the above-mentioned configuration, the back side of the liquid-permeable top sheet, the high density portion of the first layer of the second sheet is in contact, the surface of the second layer of the second sheet, Since the low density part of one layer is in contact, urine, body fluid, loose stool, etc. in the top sheet are quickly spot-absorbed by the surface layer of the first layer and pass through at a high speed, and then the back layer of the first layer. Immediately diffused in, the urine, body fluid, loose feces and the like in the top sheet and the first layer of the second sheet are taken up by the second layer of the second sheet and reach the absorber. 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.

The materials constituting the disposable diaper of the present invention will be described below. Liquid-permeable topsheet The topsheet 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.

Second sheet The second sheet comprises a first layer of the second sheet which is in contact with the liquid-permeable top sheet and a second layer of the second sheet which is in contact with the absorber, and the first layer of the second sheet is liquid-permeable. Of the first sheet and a back layer of the first layer in contact with the second layer of the second sheet. The first layer of the second sheet is fused and maintained in a web form at the intersections of the hydrophilic synthetic fibers, and has a thickness of 0.3 to 3.0 under a load of 12 g / cm ^2.
mm, the average density under a load of 12 g / cm ² is 0.
A 01~0.05g / cm ^3, further, toward the first layer surface layer of which is in contact with the liquid-permeable top sheet, density than the back surface layer of the first layer in contact with the second layer of the second sheet is It is expensive. If the average density of the first layer of the second sheet exceeds 0.05 g / 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 layer is small, so that urine, body fluid and loose stool cannot be quickly absorbed from the top sheet, and leakage tends to occur. Also, 12 g / cm ²
The thickness of the first layer of the second sheet under load is 3.0
When the thickness exceeds mm, urine, body fluid and loose stool cannot be quickly absorbed by the absorbent body from the top sheet, resulting in easy leakage. On the other hand, if it is less than 0.3 mm, the absorption rate is lowered, which is not suitable.

In the present invention, the synthetic fiber used in the first layer of the second sheet may be polypropylene, polyethylene, polyester, or a composite fiber composed of two or more components such as polyester, polypropylene and polyethylene. , Polyester / polyester, polyester / polyethylene, polypropylene / polyethylene composite fibers are preferable from the viewpoint of strength. Also,
The fiber diameter is 1.5 to 10 denier and the length is 10
Approximately 100 mm is preferable in terms of manufacturing. As a hydrophilic treatment method for these fibers and conjugate fibers, a hydrophilic agent is applied to the fibers and conjugate fibers by spraying, or the first layer of the produced second sheet is subjected to spray application, foam coating, impregnation, etc. There is a way.

Further, in the present invention, the first layer of the second sheet contains a circular cross section synthetic fiber having a circular cross section, and further, at least one of the first surface layer and the first back surface layer. In addition, 25 to 75% by weight of modified cross-section fibers having various cross-sectional shapes are contained in each layer. In this case, it is preferable that the back surface layer of the first layer contains more modified cross-section fibers than the surface layer of the first layer,
More preferably, it is contained only in the back surface layer of the first layer. By containing more modified cross-section fibers in the back layer of the first layer, the back layer of the first layer has a lower density than that of the front layer of the first layer. The reason for this is, for example,
In the case of the same denier, the cross-sectional area of the modified cross-section fiber is larger than that of the circular cross-section fiber, so that 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 layer becomes small, and it becomes impossible to quickly absorb urine, body fluid and loose feces from the top sheet, It is easy to leak. As the modified cross-section fiber, polypropylene, polyethylene, polyester, acrylic resin,
Nylon resin, etc. can be mentioned, and the cross-sectional shape is T type, W
Shapes, H-shapes, rhombuses, amoeber shapes and the like are preferable, but are not particularly limited.

In the present invention, the cotton-like pulp used in the second layer of the second sheet has a fiber length of 5 mm or less obtained by defibrating a chemical pulp sheet or a mechanical pulp sheet with a crusher. . Further, a crosslinking agent is added to the fiber, and mechanical stirring, fluffing and heat treatment are performed to have an intra-fiber cross-linking bond and deformation is imparted,
It may contain fixed fibers. 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 front surface layer of the first layer has a higher density than the back surface layer of the first layer.
The first layer of the second sheet is manufactured by being integrated by heat or the like. In order to integrate the first surface layer and the first back surface layer, two kinds of webs forming both layers are superposed, and fibers are welded 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. It can also be carried out by a heat treatment method in which a low density layer is formed by applying a low temperature.

Next, on the back layer side of the first layer of the obtained second sheet, a cotton-like pulp to be the second layer of the second sheet is laminated and then compressed and integrated. The lamination method is formed by a conventional method such as air forming, but is not particularly limited. A suitable basis weight of the laminated cotton-like pulp is 10 to 250 g / cm ² . When the basis weight of the cotton-like pulp exceeds 250 g / cm ² , urine, body fluids, loose stools, etc. are retained in the second layer of the second sheet,
It is not suitable because it does not reach the absorber and the effect of wet back is not seen. Further, when the basis weight of the cotton-like pulp is less than 10 g / cm ² , urine, body fluid and loose stool of the top sheet cannot be drawn into the second sheet, and the residual amount of the top sheet increases, resulting in a dry touch. This is not preferable because it deteriorates the property. As a compression method, compression by a press roll is advantageously carried out, but a continuous flat surface in which the density of the second layer of the second sheet is made substantially uniform over the whole by a roll having a smooth peripheral surface or the like. The second surface of the second sheet may be partially embossed with a roll having an uneven surface to guide urine, body fluids and loose stools vertically and diagonally. It may be an array.
In the case of embossing, the compressed part and the non-compressed part may be continuous or discontinuous.

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 in which the cotton-like pulp and the superabsorbent polymer are uniformly mixed and the mixture is wrapped with a hydrophilic sheet can be used. 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 raw material, not only coniferous trees, but also broad-leaved trees, straws, bamboos, kefna and the like 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 / 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 distribution amount of the superabsorbent polymer is 10 to 500%, preferably 15% of the total weight of the cotton-like pulp in a dry state.
˜300%, and such amount of superabsorbent polymer is substantially evenly distributed in the flocculent pulp. 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. .

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, 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 is made of a liquid-impermeable film such as polyethylene, a material obtained by laminating a liquid-impermeable film with a non-woven fabric, a woven fabric, or the like, and is not particularly limited. Absent.

In the members described above, for example, the top sheet and the second sheet, the second sheet and the absorber, and the absorber and the back sheet are adhered to each other by hot-melt adhesion or the like. The adhesive may be a starch-based adhesive, a water-soluble adhesive such as CMC (carboxymethyl cellulose), or an adhesive having high fluidity. The disposable diaper (absorbent article) of the present invention
The effect of the present invention can be achieved only by combining the above-mentioned top sheet, second sheet and absorber.

[0026]

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 is 30 ml of artificial stool at a height of 1 cm above the center of the used diaper in which the weight of the top sheet has been measured in advance at a distance of 1 ml / sec.
After dropping, two minutes later, 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 measuring the absorption rate (using 50 cc absorbed three times), the diaper is left for 30 minutes and then used to filter the 10 × 10 cm square filter paper (manufactured by Toyo Roshi Kaisha, Advantech No. 63) was piled up on 10 sheets, and after applying a pressure of 0.05 kg / cm ² for 5 minutes, the amount of liquid transferred to the filter paper was measured. The feeling of salat is the rate of absorption (50 cc was absorbed 3 times)
Then, the surface of the topsheet was lightly touched with a hand, and the dryness (feeling of salat) was judged by sensory evaluation. The judgment criteria were divided into the following three stages (○, Δ, ×). Salat Feeling Criteria ○: Dry △: Wet ×: Quite wet 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 Top Sheet As the hydrophilic fiber, a composite fiber made of polyester / polyethylene which was hydrophilized by spray coating and having a fiber diameter of 2 denier and a fiber length of 51 mm was used, and the basis weight was 25.0.
A topsheet with g / m ² was obtained.

Second Sheet As a first layer of the second sheet, a circular cross section fiber having a fiber diameter of 2 denier and a fiber length of 51 mm, which is a hydrophilic polyester / polyethylene composite fiber hydrophilized by spray coating, is used. , Thickness 0.40 mm,
The surface layer of the first layer having a basis weight of 12.0 g / m ² and a density of 0.030 g / cm ³ and the same hydrophilic polyester / polyethylene composite fiber as used in the production of the surface layer of the first layer 50
% W, 50% by weight of W-shaped cross-section fiber having a fiber diameter of 4 denier and a fiber length of 51 mm, which is made of hydrophilic polyester fiber, and is manufactured. Thickness 0.53 mm, basis weight 1
Using the back surface layer of the first layer of 2.0 g / m ² and the density of 0.023 g / cm ³ , the front surface layer of the first layer and the back surface layer of the first layer (weight ratio of 1: 1) were overlapped, and 150 Heat treatment at ℃ for 15 seconds to melt-bond a part of the polyethylene of the composite fiber, 12g
/ Cm ² thickness under load 0.93 mm, basis weight 24.
Average density under load of 0 g / m ² and 12 g / cm ² .
A second layer of 026 g / cm ³ second sheet was obtained. Next, using a cotton-like pulp prepared by subjecting a pulp sheet made of NBKP to a defibrating machine, the second layer of the second sheet is laminated on the back surface side of the first layer so as to have a basis weight of 30 g / m ^2. The sheet was formed and applied to a press roll having a clearance of 0.05 mm to be integrated with the first layer of the second sheet to obtain a second sheet.

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 configuration shown in FIGS. 1 and 2 in which the top sheet, a back sheet made of polyester, the absorber between the top sheet and the back sheet, and the second sheet between the top sheet and the absorber are provided. I made a disposable diaper.

Example 2 As the first layer of the second sheet, the same hydrophilic conjugate fiber as that of the surface layer of the first layer 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
g / cm ³ surface layer of the first layer, 75 wt% of the same hydrophilic conjugate fiber as used in the production of the surface layer of the first layer, and a fiber diameter of 4 denier consisting of fibers of hydrophilic polyester, fiber A T-shaped cross-section fiber having a length of 51 mm was manufactured by mixing 25% by weight, a thickness of 0.64 mm, and a basis weight of 24.4 g / m.
² , using the back layer of the first layer having a density of 0.038 g / cm ³ ,
With the exception of forming the first layer of the second sheet having a thickness of 1.04 mm under a load of 12 g / cm ² , a basis weight of 48.8 g / m ² , and an average density under a load of 12 g / cm ^{2 of} 0.047 g / cm ³ . A disposable diaper was prepared in the same manner as in Example 1.

Example 3 As the first layer of the second sheet, the same hydrophilic conjugate fiber as that of the surface layer of the first layer 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
g / cm ³ surface layer of the first layer, 25% by weight of the same hydrophilic composite fiber as used in the production of the surface layer of the first layer, and a fiber diameter of 4 denier composed of fibers of hydrophilic polyester, fiber A W-shaped cross-section fiber having a length of 51 mm was produced by mixing 75% by weight, a thickness of 1.54 mm, and a basis weight of 38.4 g / m.
² , using the back surface layer of the first layer having a density of 0.025 g / cm ³ ,
12 g / cm ² thick 2.94mm under load, except that the formation of the first layer of the second sheet of the average density of 0.026 g / cm ³ at a basis weight of ^{76.8g / m 2, 12g / cm} 2 under a load, A disposable diaper was prepared in the same manner as in Example 1.

Example 4 The same hydrophilic composite fiber as the surface layer of the first layer of Example 1 was used as the first layer of the second sheet, and the thickness was 0.15 mm and the basis weight was 9.7 g / m. ² , density 0.065g
/ Cm ³ made using the same surface layer of the first layer and the back layer of the first layer of Example 1, a thickness of 0.25 mm,
Using the first back layer having a basis weight of 9.7 g / m ² and a density of 0.039 g / cm ^3, a thickness of 0.40 mm under a load of 12 g / cm ² and a basis weight of 19.4 g / m ² , 12 g / A diaper was prepared for use in the same manner as in Example 1 except that the first layer of the second sheet having an average density of 0.049 g / cm ³ under a cm ² load was formed.

Example 5 As a second layer of the second sheet, a pallet made of NBKP was used.
Flocked pulp produced by defibrating the fiber sheet and LBK
A cotton-like pulp prepared by subjecting a pulp sheet made of P to a defibrating machine.
Mixture in a weight ratio of 1: 1 so that
200 g / m ²Laminated a second layer of a second sheet of
Except for the above, in the same manner as in Example 1, a disposable diaper is prepared.
did.

Comparative Example 1 The same hydrophilic composite fiber as the surface layer of the first layer of Example 1 was used as the first layer of the second sheet, and the thickness was 0.12 mm and the basis weight was 10.0 g / m. ² , density 0.083
Example 1 without using the W-shaped cross-section fiber used for the first surface layer of the first layer and the first layer of Example 1 in g / cm ³ .
Manufactured by using the same fiber as the surface layer of the first layer of 0.12 mm, basis weight 10.0 g / m ² , density 0.083
Using the back surface layer of the first layer of g / cm ^3, a thickness of 0.24 mm under a load of 12 g / cm ² , a basis weight of 20.0 g / m ² ,
Average density under load of 12 g / cm ² 0.083 g /
A diaper was prepared for use in the same manner as in Example 1 except that the first layer of the second sheet of cm ³ was formed.

Comparative Example 2 As the first layer of the second sheet, 20 wt% of the same hydrophilized conjugate fiber as the surface layer of the first layer of Example 1 was used, and W was used for the back layer of the first layer of Example 1. 80% by weight of mold cross-section fibers were mixed and produced, thickness 1.11 mm, basis weight 10.2
g / m ^2, and the surface layer of the first layer of density 0.009 g / cm ^3, and the same W-shaped cross section fibers as used for the surface layer of the first layer was prepared by using 100 wt%, thickness 1 .10 mm, basis weight 10.2 g / m ² , density 0.009 g / cm ³ using the back layer of the first layer, thickness under load of 12 g / cm ² 2.21 mm, basis weight 20.4 g / m ² , except for forming the first layer of the second sheet of the average density of 0.009 g / cm ³ under a 12 g / cm ² load, in the same manner as in example 1 to prepare a disposable diaper.

Comparative Example 3 As the first layer of the second sheet, except that the front surface layer of the first layer and the back surface layer of the first layer in Example 1 were reversed, that is, the first layer was replaced with the back layer of the first layer. A diaper was prepared by using it in the same manner as in Example 1 except that the surface layer had a low density.

COMPARATIVE EXAMPLE 4 As the first layer of the second sheet, the same hydrophilic fiber as that of the surface layer of the first layer of Example 1 was used and the thickness was 0.3.
6 mm, basis weight 24.4 g / m ² , density 0.068 g / c
a first layer surface layer of m ^3, was prepared using the same fiber as the back layer of the first layer of Example 1, thickness of 0.40 mm, a basis weight of 24.4 g / m ^2, density 0.061g / using the first layer backside layer of cm ^3, 12g / cm ² thick under load 0.
In the same manner as in Example 1 except that the first layer of the second sheet having a weight of 76 mm, a basis weight of 48.8 g / m ² , and an average density of 0.064 g / cm ³ under a load of 12 g / cm ² was formed.
Used to make a diaper.

Comparative Example 5 A diaper for use was prepared in the same manner as in Example 1 except that the second sheet was not used. The above-mentioned characteristics were evaluated using the used diapers produced in Examples 1 to 5 and Comparative Examples 1 to 5 described above. Table 1 shows the test results.

[0039]

[Table 1]

As shown in Table 1, the characteristics of Comparative Examples 1 to 5 are considerably inferior to those of Examples 1 to 5, and the effect of the present invention was confirmed.

[0041]

As described above, by using the absorbent article of the present invention, urine, body fluids, loose stools, etc. in the top sheet that comes into contact with the skin of the user are transferred to the surface layer of the first layer of the second sheet. The spot is quickly absorbed and passes at a high speed, and then immediately diffused in the back layer of the first layer of the second sheet, and further in the second layer of the second sheet, the urine, the body fluid and the urine of the top sheet and the first layer of the second sheet. Soft stools, etc. are collected and reach the absorber. 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 second seat shown in FIG.

[Explanation of symbols]

 1. Liquid permeable top sheet 2. Second seat 3. First layer of second sheet 3a. First surface layer 3b. Back layer of the first layer 4. Second layer of second seat 5. Liquid impermeable back sheet 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. An absorbent material comprising an absorbent body disposed between a liquid-permeable top sheet and a liquid-impermeable back sheet, and a second sheet disposed between the liquid-permeable top sheet and the absorbent body. In the article, the second sheet is composed of a second layer of the second sheet in contact with the liquid-permeable top sheet and a second layer of the second sheet in contact with the absorber, and the first layer of the second sheet is hydrophilic. The synthetic fiber is fused at the intersection and maintains the web form,
And the thickness under load of 12 g / cm ² is 0.3 to 3.
0 mm, the average density under load of 12 g / cm ² is 0.01 to 0.05 g / cm ³ , and the surface layer of the first layer in contact with the liquid permeable top sheet is more Higher density than the back layer of the first layer in contact with the second layer, the second layer of the second sheet is composed mainly of cotton pulp, the first layer of the second sheet and the second layer of the second sheet. An absorbent article, which is formed by stacking layers. 2. The first layer of the second sheet includes synthetic fibers having a circular cross section, and further, a modified cross section fiber is provided in at least one of the front layer of the first layer and the back layer of the first layer for each layer. 25-75 weight% is contained, The absorbent article of Claim 1 characterized by the above-mentioned.