JPH01314704A - Disposable diaper - Google Patents

Abstract

PURPOSE:To obtain the subject diaper having plural absorbing layers consisting of an absorbing core between the surface sheet of a liquid-permeable front side sheet and a liquid-impermeable back side sheet and a highly absorbing granular substance arranged in the form of a pattern between the layers with a high permeation and absorption rates of excreta. CONSTITUTION:The objective disposable diaper obtained by arranging an absorbing core 3 consisting of plural absorbing layers and highly highly absorbing granular substance 8 placed in the interlayers of the absorbing layers between a liquid-permeable front surface sheet 1 (e.g., dry nonwoven fabric) and a liquid- impermeable back side sheet 2 (e.g., polyethylene film) in the form of a pattern. Furthermore, the absorbing layers constituting the absorbing core 3 preferably have a structure with plural absorbing fiber layers 7 and 9 (e.g., fluffy pulp) between the water absorbing sheets 10 and 11 (e.g., tissue paper) on the and bottom surfaces.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a disposable diaper that more effectively absorbs body excreta.

[Prior Art] The absorbent core of conventional disposable diapers is either one in which a superabsorbent polymer is uniformly distributed over the entire surface between absorbent fiber layers, or a layered material in which absorbent fibers and superabsorbent polymer are mixed. In addition, there are those in which a sheet-like material in which a superabsorbent polymer is integrally formed between a front material and a back material is used in the intended portion of the absorbent core. For example,
-11210 Publication states that at least two of the three quarter lines that divide the longitudinal direction of the absorbent pad into quarters include the center line.
Disclosed is a disposable diaper containing super absorbent polymer sheets 1 to 1 divided into parts near the quarter line of the book.

Japanese Unexamined Patent Publication No. 62-170246, No. 62-17024
Publication No. 7 discloses that in an absorbent body for an absorbent sanitary article in which superabsorbent polymer particles are mixed in the fiber web, the superabsorbent polymer particles form clusters such as vertical striped patterns or wave patterns in the fiber web. An absorber that is distributed intermittently in the surface direction and continuously in the thickness direction has been proposed.

[Problems to be Solved by the Invention] However, in the above-mentioned conventional disposable diapers, when arranging the superabsorbent polymer in the absorbent layer or the absorbent body, the superabsorbent polymer is either sprayed over the entire surface of the absorbent body or mixed with the fiber web that constitutes the absorbent body. It has been difficult to control the distribution state of the superabsorbent polymer particles on or within the absorbent body because they are mixed in the absorbent body or made into a water absorbent polymer sheet and sandwiched between the water absorbent fiber layers.

Even if an attempt was made to form a desired distribution state on the surface of the absorbent body, it would be complicated, such as requiring a separate process for disposing the superabsorbent polymer or creating a superabsorbent polymer sheet as described above. Ta.

In general, when a superabsorbent polymer exists in a continuous layer in the surface direction inside an absorbent core, the superabsorbent polymer that has become a rigel-like substance due to excrement is sometimes used twice or three times while wearing a diaper.
When excretion and excretion are performed, the gel layer acts as a barrier layer and inhibits absorption, especially from the second time onwards, which slows down the absorption rate and makes it easier for excrement to leak. In addition, when excrement is absorbed by the superabsorbent polymer and gelatinization progresses, the absorption capacity of the superabsorbent particulates is high, so the excrement is retained in the absorbent sheet located in the groin area, making it easy to collect and diffuse. It becomes insufficient. 1 discharge per unit area! The amount of things will also increase,
This is undesirable because the amount of leakage and the amount of excrement that passes through the diaper surface sheet 1- and returns to the skin increases.

[Means for Solving the Problems] (Objective) The purpose of the present invention is to eliminate the above-mentioned drawbacks of disposable diapers, such as absorption, diffusion, and return of excrement, and to effectively utilize highly absorbent granules. Our goal is to provide disposable diapers that can

(Structure) In order to achieve the above object, the present invention arranges superabsorbent granules in a pattern in the plane direction of an absorbent layer consisting of absorbent fibers forming an absorbent core and absorbent sheets 1 to 1. The present invention relates to a structure of a disposable diaper that can effectively absorb excrement throughout the surface and thickness directions of an absorbent core by laminating layers in multiple stages.

The present invention provides a disposable diaper comprising a liquid-permeable top sheet, a liquid-impermeable back sheet, and an absorbent core disposed between these two sheets, wherein the absorbent core comprises a plurality of absorbent layers, and This disposable diaper is characterized in that highly absorbent granules are arranged in a pattern between a plurality of absorbent layers.

Further, the disposable diaper is provided with the absorbent layer made of an absorbent IJ fiber layer or an absorbent sheet, and in which superabsorbent granules are arranged in a pattern between the layers in which a plurality of the absorbent layers are laminated.

Furthermore, the disposable diaper is a disposable diaper in which highly absorbent granules are arranged in a pattern, in which a plurality of absorbent layers are laminated with an uneven pattern formed on the absorbent layer, and highly absorbent granules are arranged in the recesses of the uneven pattern. .

Furthermore, the disposable diaper has highly absorbent granules concentrated in the central region of the surface of the absorbent layer and arranged in a pattern.

(Embodiments) The embodiments of the present invention will be described below with reference to the drawings.

As shown in FIG.
-1, a liquid-impermeable back sheet 2, and an absorbent core 3. As the liquid-permeable surface sheet 1~, a dry nonwoven fabric, a perforated film, etc. are used, and as the liquid-impermeable back sheet 1~, a polyethylene film, a water-repellent nonwoven fabric, etc. are used.

As shown in Figures 2 to 7, the absorbent core is made of water permeable sheets such as tissue paper and dry pulp nonwoven fabric on the top and bottom surfaces, and the space between the top and bottom sheets is made of fluff pulp, rayon, etc. Absorbent fiber layer7.
It consists of two layers of 9 or more layers. 8. Highly absorbent particles are present between the layers of the absorbent layer, which corresponds to the central region of the surface of the absorbent layer.
13, 18, 28, and 30 are arranged in a pattern (the drawing shows only the central region), and when the superabsorbent particles exist between two or more absorbent layers, the pattern arrangement between each layer is They can be combined depending on the purpose as shown in FIG.

It is also possible to use a water absorbent sheet between the water absorbent fiber layers and form highly absorbent granules in a pattern on this sheet.

The highly water-absorbing granules used in the present invention include commonly known highly water-absorbing polymer particles alone or mixed with activated carbon and carboxymethyl cellulose.

[Example] Embodiments of the present invention will be described with reference to the drawings.

As an example, FIG. 2 shows two absorbent fiber layers 7 and 9 in which superabsorbent granules 8 are covered with absorbent sheets 10 and 11 on the upper and lower sides.
It is located between the layers and forms a vertical striped pattern. The sushi of superabsorbent granules is formed by parts with a large amount and parts with a small amount, or parts where it is present and parts where it is not present. The sushi pattern of superabsorbent granules can be formed in the absorbent layer from a rotary feeder or screw feeder, or
It can be formed by providing a guide between the feeder and the absorbent layer that causes the highly absorbent granules to protrude in a sushi-like manner. Naturally, these aspects are also included in the present invention.

However, the above embodiment is limited to a simple pattern arrangement such as a vertically continuous stripe pattern or an intermittent sushi pattern.

As a method for easily obtaining a complicated pattern arrangement, as shown in FIGS. 3 and 4, there is a three-dimensional surface on which absorbent layers such as the absorbent fiber layer 12, the absorbent sheet 21, and the absorbent fiber layer 17 are arranged in a pattern. to form an uneven pattern on its surface. By scattering highly absorbent granules on the uneven absorbent layer, it is possible to form a patterned arrangement in which the granules are arranged in a larger amount in four parts.

Preferably, by applying appropriate vibration after dispersing the superabsorbent granules, the superabsorbent granules can more easily enter the four parts, and the pattern arrangement becomes clearer. According to this method, different types of patterns can be easily formed by changing the uneven molding surface.
There are no restrictions on the type.

Although the shape of the unevenness is vertical striped in the drawing, various uneven patterns such as a horizontal grid pattern, a vertical and horizontal grid pattern, or a circular convex pattern can be provided.

FIG. 7 shows an embodiment in which superabsorbent granules are stacked to form two types of patterned arrangements. Absorbent IIi NM 27 has vertical irregularities, circular protrusions 34 on absorbent m delamination 29
and superabsorbent granules 28 in the recesses.

30 is present in a patterned arrangement. Absorbency 1!
Molding of the chick layer 27, formation of patterned arrangement, absorbent fiber layer 29
It is also possible to perform lamination molding, to form a patterned arrangement, and to laminate these different kinds of patterned arrangements in multiple stages.

When the absorbent core obtained in this way is compressed using a calender, the load is concentrated on the area where the highly absorbent granules are present, so the density of the absorbent layer in the area close to the highly absorbent granules decreases. An absorbent core is obtained which has a higher density than the area where the superabsorbent granules are not present.

[Effects of the Invention] In the diaper according to the present invention, in the above-mentioned absorbent core, the superabsorbent particulates form a patterned arrangement in the central region of the absorbent layer, so that the part where the superabsorbent particulates are not present or The so-called convex portions of the molding of the absorbent layer, which are present in small amounts, allow excrement to be absorbed at a high rate, and the rate of permeation in the thickness direction of the absorbent core is also high. (See Figure 8) In areas where there are many highly absorbent particles, the density of the suction layer near the highly absorbent particles is high, so the diffusion rate of excrement is fast, and absorption It diffuses in the longitudinal direction of the sex core and is effectively absorbed over the entire area of the absorbent core. These absorption speed and diffusivity are also effective in preventing the leakage of excrement, allowing the wearer to use it comfortably.

Furthermore, the amount of excrement per unit area is reduced by dispersing it over the entire area of the absorbent core. Furthermore, when the part where the highly absorbent particulates are present absorbs excrement, it becomes gelled and its volume increases. Moreover, unlike an absorbent layer, gel is less likely to release excrement under pressurized conditions (e.g., the weight of a human body). In this state, as shown in FIGS. 5 and 6, the gel portion swells and pushes up the upper absorbent layer, so that ridges are formed in the striped pattern arrangement. In other patterned arrangements, the gel-covered portions swell up, and the gel-free portions form a depressed crater. 2 cases of defecating while wearing a diaper
When this is done once or thrice, the excrement tends to spread along the troughs 40 of the ridges, and the absorbent core is better able to spread in the vertical direction, while the peaks 41 prevent it from spreading in the lateral direction. In this patterned arrangement, the surface that comes into contact with the skin tends to be a white part with a lot of gel that does not release raised excrement, giving the wearer a good dry feeling.

As mentioned above, when highly absorbent granules form a patterned arrangement and are laminated in multiple layers, the presence of the highly absorbent granules creates a pathway for rapid absorption of excrement, as shown in Figure 8. Highly absorbent particulate matter is present in areas where it is not present or present in small amounts, and in any part of the thickness direction.
A dry feeling is more desirable for the wearer.

[Brief explanation of the drawing]

The drawings show embodiments of the disposable diaper of the present invention, and FIG. 1 is a partially cutaway exploded plan view of the structure of the disposable diaper, and FIGS. A partially cutaway perspective view of the sex core, Figure 5 is a partially cutaway perspective view of the absorbent core in Figure 3 after absorbing excrement, and Figure 6 is a partially cutaway perspective view of the absorbent core in Figure 3 after absorbing excrement. The cross-sectional view after absorption, FIG. 8 is a partially enlarged explanatory view of the cross-sectional view taken along the line A--A after passing through the calendar in FIG. DESCRIPTION OF SYMBOLS 1... Top sheet, 2... Back sheet, 3... Absorbent core, 4.5... Elastic band, 6... Fastening tape, 7, 9, 12.14.17.19 .27
．． 29.31...Absorbent fiber layer, 10.11.15.
16.20.21.32.33.48...Absorbent sheet, 8.13.18.28.30...Highly absorbent granules, 23.36...Excrement from highly absorbent granules Gel-like substance after absorption, 34...Circular convex portion, 40...Trough, 41
...Yamabe.

Claims (1)

[Scope of Claims] 1. A disposable diaper comprising a liquid-permeable top sheet, a liquid-impermeable back sheet, and an absorbent core disposed between these two sheets, wherein the absorbent core is composed of a plurality of absorbent layers. A disposable diaper characterized in that the highly absorbent granules are arranged in a pattern between the plurality of absorbent layers. 2. The disposable diaper according to claim 1, wherein the absorbent layer is composed of an absorbent fiber layer and an absorbent sheet, and superabsorbent granules are arranged in a pattern between the plurality of laminated absorbent layers. 3. The absorbent layer according to claim 1, wherein the absorbent layer has a concavo-convex pattern formed thereon, and a plurality of absorbent layers in which highly absorbent granules are arranged in the recesses of the concavo-convex pattern are laminated, and the superabsorbent granules are arranged in a pattern. disposable diapers. 4. The disposable diaper according to claim 1, wherein the superabsorbent granules are concentrated in the central region of the surface of the absorbent layer and arranged in a pattern.