JPH01285265A - Absorbant article - Google Patents

Abstract

PURPOSE:To enhance the leak-proof property accompanied by the movement of a user without damaging the excellent absorbability of an absorbing body, by providing an elastomer composed of fiber aggregate based on a synthetic fiber to the lower part of the absorbing body provided between a liquid permeable surface layer and a liquid impermeable leak-proof layer. CONSTITUTION:A liquid permeable surface layer 1 and a liquid impermeable leakproof layer 3 and the absorbing body 2 having liquid retentivity between both layers are provided and an elastomer 2 composed of fiber aggregate based on a synthetic fiber is provided to the lower part of the absorbing body 2. As the suitably used elastomer, the fiber aggregate (web) based on the synthetic fiber such as a polyester fiber, an acrylic fiber, an acetate fiber, a polyolefin fiber or the like is designated and, by variously changing a fiber basis wt., the kind of a fiber, a crimping degree and the blending between different kinds of fibers, the stress buffering characteristic of said web can be freely controlled. Further, bending rigidity is low and no feeling of physical disorder is given to a user.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to absorbent articles such as sanitary napkins, disposable diapers, and incontinence pads. The present invention relates to an absorbent article that significantly reduces leakage that occurs during exercise.

[Prior art and problems to be solved by the invention] Conventional absorbent articles, such as sanitary napkins or disposable diapers, basically consist of an absorbent body made of cotton-like pulp, etc., and arranged on the bottom and side surfaces of the absorbent body. It consists of a leak-proof layer and a surface layer placed on top.

In recent years, with the rapid improvement of technology, new materials such as superabsorbent polymers and dry-laid nonwoven fabrics mainly made of synthetic fibers have been introduced, and the absorption performance has been significantly improved. However, even absorbent articles made of materials with excellent performance cannot be said to fully demonstrate their original performance during actual use.

This is evident from the fact that the biggest consumer complaint about such absorbent articles remains leakage from the crotch area.

The biggest cause of this leakage is that excessive stress is applied to local areas of the absorbent article due to movement of the wearer's groin area, and the liquid that should be held in the absorbent body in these local areas returns to the surface of the absorbent article. This is because the particles diffuse toward the edges of the absorbent article.

Various proposals have been made as means to prevent this leakage.

First, a technique has been proposed to prevent leakage by adding highly elastic synthetic fibers to an absorbent body made of pulverized pulp or the like to maintain the capillary structure in the absorbent body even under excessive stress.

However, synthetic fibers are inherently poor in hydrophilicity no matter how they are treated to make them hydrophilic, resulting in a decrease in the absorbency of the entire absorbent body, and as a result, liquid retention/retention on the surface layer.
There is little improvement in leaktightness due to increased diffusion.

Furthermore, a technique has been proposed in which an intermediate layer made of highly elastic synthetic fibers is provided between the surface layer and the absorbent body to buffer excessive stress, thereby improving leakage prevention.

However, this technique also involves diffusion/retention of liquid in the surface layer due to the poor hydrophilicity of synthetic fibers.
Leak-proofing properties have hardly been improved.

In this way, with conventional techniques, it has not been possible to suppress leakage caused by excessive local stress without impairing the excellent absorbency of the absorbent body, so it is possible to obtain an absorbent article with excellent leakproof properties. I couldn't do that.

[Means for Solving the Problems] Therefore, the inventors of the present invention have conducted intensive studies to solve the problems of front running, and as a result, the inventors of the present invention have developed a method that can be used in conjunction with the user's exercise without impairing the excellent absorbency of the absorbent material. By alleviating the local excessive stress caused by this, we succeeded in obtaining an absorbent article with significantly improved leak-proofing properties, and completed the present invention.

That is, the present invention provides an absorbent article having a liquid-permeable surface layer, a liquid-impermeable leak-proof layer, and an absorbent body provided between both layers, in which fibers mainly composed of synthetic fibers are provided below the absorbent body. The present invention provides an absorbent article including an elastic body made of an aggregate.

Hereinafter, the present invention will be explained in more detail based on the drawings.

FIG. 1 is a cross-sectional view of a typical embodiment of the absorbent article according to the present invention, where ■ is a liquid-permeable surface layer, 2 is a liquid-retaining absorbent body, 3 is a liquid-impermeable leak-proof layer, 4 is an elastic body.

The elastic body suitably used in the present invention includes a fiber aggregate (web) mainly made of synthetic fibers such as polyester fiber, acrylic fiber, acetate fiber, and polyolefin fiber, which buffers the stress applied to the absorbent body. Any material may be used as long as it has a restoring property. The stress buffering properties of these synthetic fiber-based webs can be freely controlled by varying the fiber basis weight, fiber type, degree of crimp, mixing of different types of fibers, etc. , and the effect is great. In addition, they generally have lower bending rigidity than nonwoven fabrics, foam sheets, etc., so they do not give a strange feeling to the user (and are inexpensive).

The stress buffering characteristic of the elastic body in the present invention is expressed by the compression characteristic value K given by the following equation, and the larger the value, the greater the stress buffering effect.

h=ha exp (-kP) ho: Thickness of (absorbent elastic body) under no pressure h: Thickness of (absorbent elastic body) under pressure (P) P: Pressure k: Compression characteristic value book In the invention, those with a k value of 0.14 cm''/g or more are preferably used, and the absorbency tends to improve as the k value increases, but those with a k value lower than that are preferable because the stress buffering effect becomes poor. do not have.

In the present invention, the elastic body may be formed at any position as long as it is the lower part (unused surface side) of the absorber as shown in FIG. Only the center part in the width direction (Fig. 2 (b)), only the ends in the width direction (second part)
(Fig. (C)), or a structure that is wider than the absorber and is installed so as to form flaps at both ends in the width direction. The effect tends to be higher when the absorber is installed so as to span both ends in the width direction of the absorber. Further, the cross-sectional position of the elastic body is preferably at the bottom of the absorbent body and at the top of the liquid-impermeable leak-proof layer.

In the present invention, when the elastic body has sufficient liquid absorption permeability, a second layer is further added to the lower part (unused surface side) of the elastic body 4 as shown in FIGS. 1(f) and (g). It is also possible to install absorbent paper, a valve, etc. as the absorber 6, and the absorption characteristics can be further improved.

In addition, as shown in FIG. 1(d), an elastic body 4 is installed at the bottom of the absorbent body 2, and an elastic body 4'' is further installed at the top of the absorbent body 2.
Alternatively, as shown in FIG. 1(e), it is also possible to add synthetic fibers 5, etc. to the absorbent body 2. In this case, the absorption characteristics of the absorbent body are not deteriorated (therefore,
Even if the amount is as small as (the liquid retention rate on the surface layer does not increase), combined with the effect of the elastic body installed at the bottom of the absorber, excellent absorption characteristics will be exhibited.

As the surface layer of the absorbent article of the present invention, any material can be suitably used as long as it has excellent liquid absorption permeability and good texture, and nonwoven fabrics and Various films such as perforated films can be used, and among them, the smaller the diffusion/retention of liquid on the surface layer such as perforated films, the better the absorption performance.

〔Example〕

EXAMPLES Hereinafter, the present invention will be explained in more detail with reference to Examples, but it goes without saying that the present invention is not limited to these Examples.

Example 1 20g/+s" polyolefin nonwoven fabric (polyethylene-polyester composite fiber 100% liquid-permeable surface layer)
%), polylaminated waterproof paper made by laminating polyethylene to a waterproof paper with a thickness of 8μ as a leak-proof layer, cotton-like pulp (180 g/m") as an absorbent, and absorbent paper (33 g/m", 2
ps), using 0.3 g of superabsorbent polymer, and
Test samples having various configurations shown in FIG. 1 were manufactured by adding the various elastic bodies shown in FIG. The dynamic maximum absorption amount of this test sample was measured by the following method. In addition, the discomfort felt when worn was also evaluated.

The results are shown in Table-1.

Dynamic Maximum Absorption Amount As shown in FIG. 3, the test sample 9 was attached to the movable female waist model 7 as shown in FIG. While doing so, pseudo blood was injected through the dripping tube 8, and the amount absorbed until side leakage occurred was measured.

<Uncomfortable feeling> Test samples were worn by five healthy adult women.
Based on the results of asking respondents whether or not they felt uncomfortable, they were ranked as follows.

○: Less than two people felt uncomfortable.

×: Three or more people felt uncomfortable.

〔Effect of the invention〕

Since the absorbent article of the present invention has an elastic body made of a fiber aggregate mainly composed of synthetic fibers disposed at the bottom of the absorbent body, the absorbent article can be easily applied to the absorbent body without impairing the excellent absorption performance of the absorbent body. It is possible to effectively buffer the applied stress, and as a result, even if excessive stress is applied to the absorbent body when worn, the absorbent body will not twist or become loose, effectively preventing leakage. things became possible.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing various embodiments of the absorbent article of the present invention, and FIG. 2 is a diagram showing the positional relationship between the absorbent body and the elastic body of the absorbent article of the present invention. FIG. 3 is a perspective view of a movable female waist model, showing that an elastic body is installed in the area where the elastic body is placed, and FIG. 4 is a perspective view showing a state in which a test sample is attached to the model. l...Liquid-permeable surface layer 2...Absorbent body 3...Liquid-impermeable leak-proof layer 4'', 4...Elastic body 5...Synthetic fiber 6...Second absorbent body 7...Movable female waist model 8...Liquid injection tube 9...Test sample Applicant's agent Kaoru Furuya Figure 1 Figure 2

Claims (1)

[Claims] 1. In an absorbent article having a liquid-permeable surface layer, a liquid-impermeable leak-proof layer, and an absorbent body provided between both layers,
An absorbent article comprising an elastic body made of a fiber aggregate mainly composed of synthetic fibers provided below the absorbent body.