JP3161638B2 - Absorbent articles - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an absorbent article such as a sanitary napkin and, more particularly, to a liquid-permeable surface material, a back material, and an absorber provided therebetween. The present invention relates to an absorbent article having three-dimensional gathers for preventing lateral leakage on both side portions of the surface material.

[0002]

2. Description of the Related Art Absorbent articles such as sanitary napkins and pads for incontinent persons are provided at the center with an absorbent for absorbing and retaining body fluids such as urine and menstrual blood excreted from the body. It has a flexible liquid-permeable surface material disposed on the side in contact with the body and a liquid-impermeable back material disposed on the side opposite to the body. By the way, the outer shape and structure of an absorbent article are important factors in exhibiting a comfortable feeling and body fluid absorption, and various proposals of an absorbent article relating to these are made. For example, in a sanitary napkin described in JP-A-60-193461, an elastic member is provided on a side edge of the sanitary napkin so that the center of the napkin has a shape similar to a cup.
In the sanitary napkin described in Japanese Patent Application Laid-Open No. 58-67258, an upright wall is formed on the upper side edge of the absorbent layer, that is, at the side portion of the surface material, by forming an upright wall with the back material extending therefrom. And prevent lateral leakage of menstrual blood. Furthermore, the applicant of the present application has disclosed in Japanese Patent Publication No. 60-54411 a sanitary napkin in which a surface material is provided with a thread material which contracts and expands after absorbing a liquid so that the surface material can have irregularities after absorbing a body fluid. Proposals are being made to improve comfort.

[0003]

However, conventional sanitary napkins and the like have a boat-like shape from the beginning due to elastic members and upright walls, so that it is difficult to fix them to underwear such as shorts when worn. there were. In addition, the use of the elastic member is complicated in manufacturing. Further, it is difficult to individually package the product packaging, and even if it is individually packaged, there is a risk that the shape of the hull cannot be maintained due to downsizing.
For this reason, it became inconvenient to carry. Further, with a sanitary napkin in which surface materials are made uneven, even if the feeling of comfort is improved, lateral leakage of menstrual blood could not be prevented. Therefore, an object of the present invention is to provide a three-dimensional gather forming body which is easy to mount and manufacture, and has no problem in the individual packaging form. It is an object of the present invention to provide an absorbent article formed to sufficiently prevent lateral leakage such as menstrual blood.

[0004]

SUMMARY OF THE INVENTION The present invention relates to an absorbent article comprising a liquid-permeable front material, a back material, and an absorber provided therebetween, which shrinks and absorbs elasticity after absorbing the liquid. The yarn material to be exerted is disposed integrally with the gather forming sheet in the longitudinal direction and the width direction of the sheet, and one end along the longitudinal direction of the sheet is fixed to the surface material and the other end is a free end. A pair of three-dimensional gather forming bodies, wherein the free ends are erected from the surface material surface by the contraction and elasticity of the thread material after absorbing the liquid. The above object has been achieved by providing an absorbent article characterized by being provided on the above-mentioned surface material along both sides in the longitudinal direction. Here, the three-dimensional gather forming body refers to a body that functions as a three-dimensional gather only when liquid is absorbed.

[0005]

In the above-mentioned absorbent article, the three-dimensional gather-forming body does not form a hull shape before being worn, and can be easily mounted individually, and can be easily fixed to underwear such as shorts. Also, there is no need to handle the elastic member or the like, and no complicated manufacturing is required.
On the other hand, once the absorbent article absorbs bodily fluids after being worn, the free end of the three-dimensional gather forming body rises from the surface material surface due to the longitudinal shrinkage and the shrinkage in the width direction of the thread material, thereby forming three-dimensional gathers. A hull shape is formed on the mounting surface.
Therefore, there is no lateral leakage of body fluid such as menstrual blood, and discomfort due to body fluid or the like is reduced.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an absorbent article according to the present invention will be described in detail with reference to the drawings. FIG. 1A is a plan view of an absorbent article (sanitary napkin) according to the present invention, FIG. 1B is a cross-sectional view of the sanitary napkin along a longitudinal direction, and FIG. It is sectional drawing along the width direction. 2A is a cross-sectional view along the longitudinal direction of the sanitary napkin after absorbing the bodily fluid of FIG. 1, and FIG. 2B is a cross-sectional view along the width direction of the sanitary napkin after absorbing the bodily fluid of FIG. is there. FIG. 3 is a sectional view of a thread material attaching portion used for the sanitary napkin of FIG. FIGS. 4A and 4B are cross-sectional views showing another embodiment of the thread material attaching portion of the sanitary napkin according to the present invention, and FIGS. 5A and 5B according to the present invention. It is the top view which showed another aspect of the thread material attachment position of a sanitary napkin. As shown in FIG. 1, the absorbent article (sanitary napkin 1) according to the present embodiment is characterized in that it comprises a liquid-permeable surface material 2, a back material 3, and an absorber 4 provided therebetween. This is the same as known absorbent articles. Thus, in the sanitary napkin 1 according to the present embodiment, the thread material 7 that contracts after absorbing the liquid and exhibits elasticity is arranged integrally with the gather forming sheet 6 in the longitudinal direction and the width direction of the sheet 6, One end 6A along the longitudinal direction of the sheet 6 is fixed to the surface material 2 and the other end is a free end 6A.
B is a three-dimensional gather forming body 5 and a pair of three-dimensional bodies arranged so that the free end 6B can be erected from the surface material 2 by the contraction and elasticity of the thread material 7 after absorbing the liquid. The gather forming body 5 is provided on the surface material 2 along both sides in the longitudinal direction of the absorber 4.

More specifically, as shown in FIG. 1, both side portions 2 of a surface material 2 of a sanitary napkin 1 are shown in FIG.
A solid gather forming body 5 is attached to each of A and 2B. The three-dimensional gather forming body 5 is composed of a liquid-impermeable strip-like gather forming sheet 6 and a thread material 7, and one end 6 A of the gather forming sheet 6 is attached along each side of the surface material 2. . Gather forming sheet 6
The other end is a free end 6B, and as shown in FIG. 2, the free end 6B can stand up from the surface material 2 surface. Therefore, the three-dimensional gather forming body 5 does not stand up when the liquid is not absorbed as shown in FIG.

The thread material 7 is a free end 6 of the gather forming sheet 6.
B (longitudinal direction) and diagonally from the free end 6B side to the mounting end 6A side (width direction), and the end 7A of the thread material 7 is attached to the surface material 2 together with the gather forming sheet 6. It is fixed. The thread material 7 shrinks due to liquid absorption and has elasticity. As such a thread material, carboxymethylation (hereinafter referred to as CM) proposed by the present applicant in Japanese Patent Publication No. 60-54411 has already been proposed. ). A twisted cellulose yarn can be used. That is, it is important that the yarn material 7 has a shrinkage rate of 10% or more, and it is particularly desirable that the shrinkage rate be 20 to 40%.
Such characteristics are caused by the degree of CM and the twist coefficient of the yarn material. By satisfying these conditions, the yarn material used in the present invention is provided.

For example, the CM-modified cellulose yarn material used in the present invention may be a single-ply yarn twisted in a single strand, a plurality of twisted single-ply yarns, or a cross-linked CM-modified cellulose yarn. The CM-modified cellulose yarn preferably has a degree of CM (DS) of at least 0.15 or more, and a twist coefficient of at least 3.0 or more. If the degree of CM (DS) and the twist coefficient are below the above ranges, sufficient shrinkage and shrinkage force cannot be obtained. Examples of the CM-formed cellulose yarn material used in the present invention include yarns obtained by CM-forming cellulose yarn such as cotton and polynosic rayon. Examples of the crosslinking agent for the crosslinked CM cellulose yarn include glyoxal, epichlorohydrin, ethylene glycol, and glycidyl ether. In addition, the CM-modified cellulose yarn used in the present invention has a C content as described above.
One obtained by twisting a plurality of CM-modified cellulose single yarns having an M degree, or one obtained by twisting a CM-modified cellulose single yarn with another non-water-absorbing shrinkable yarn such as cotton, rayon yarn or synthetic fiber may be used. In this case, the twist coefficient is preferably 3.0 or more, and the mixing amount of the other non-water-absorbing shrinkable yarn is preferably not more than 50% by weight so as not to reduce the shrinkage force of the yarn material.

As shown in FIG. 3, the gather forming sheet 6 of the three-dimensional gather forming body 5 includes a liquid-permeable sheet portion 6a and a liquid-impermeable sheet portion 6b, and wraps the thread material 7 at the free end 6B. It is folded back. In this embodiment, the liquid-permeable sheet portion 6a is provided on the skin contact side (outside), but the thread material 7 may absorb the wet back liquid of the bodily fluid once absorbed from the surface material 2. For this reason, the liquid-permeable sheet portion 6a may be provided on the surface material side (inside).

The surface material 2 may be a known material as long as it is a liquid-permeable sheet, and examples thereof include a woven fabric, a non-woven fabric, and a porous sheet.
Examples include rayon, polyester, polyethylene, and polypropylene. The backing material 3 may be a known material as long as it is a liquid-impermeable sheet. In particular, a moisture-permeable liquid-impermeable sheet obtained by adding a filler or the like to a thermoplastic resin, or a material having a feel similar to underwear For example, a strongly water-repellent nonwoven fabric or a composite material of a film and a woven fabric can be used. Note that the liquid-impermeable sheet portion 6b of the gather forming sheet 6 can be the same as the back material 3. The absorber 4 is not particularly limited as long as it is excellent in absorbing and retaining bodily fluids, and the thickness and shape are appropriately selected according to the purpose. The thickness ranges from 1 to 10 mm. Examples of the material of the absorber 4 include defibrated pulp, cellulose fiber, and thermoplastic resin, and a polymer water-absorbing polymer known per se can be used together with these.

The sanitary napkin 1 has a total stiffness in the range of 1 g · cm to 50 g · cm, and the thread material 7 after absorbing the liquid.
It is important that the stress at 50% elongation is in the range of 5 g to 150 g, and preferably, the total stiffness is 3 g · c.
m to 20 g · cm, particularly 5 g · cm to 10 g · cm, and a preferred stress is 20 g to 50 g. When the stiffness of the sanitary napkin 1 and the expansion and contraction rate of the thread material 7 are within the above-mentioned ranges, a preferred hull form is formed when the body fluid is absorbed. If the stiffness of the sanitary napkin 1 falls below the above range, sufficient shape retention of the napkin cannot be obtained, and if it exceeds the above range, a hull form after absorbing the liquid will not be formed sufficiently. If the stretch ratio of the thread material 7 is below the above range, a sufficient hull form cannot be formed, and if it exceeds the above range, a favorable hull form cannot be obtained.
The stiffness was measured using a Taber stiffness tester (manufactured by Kumagai Riki Kogyo Co., Ltd.). The measurement was performed by cutting a 38 mm × 70 mm sample piece from the center of the sanitary napkin at 23 ° C. and 50% environment. After conditioning for 24 hours, attach the sample to the measuring device so as not to compress it.
The average of zero measurements. Other conditions include TA
Measured according to the requirements of PPI T489-os70.
The stress is measured by using a universal tensile tester (Orientec Co., Ltd.), measuring 100 mm of the thread material on the tester, and measuring the stress when the yarn is stretched to 150 mm.

Sanitary napkin 1 constructed as described above
When a body fluid such as menstrual blood passes through the surface material 2 and is absorbed by the absorber 4, a part of the body fluid passes through the liquid-permeable sheet portion 6 a of the gather forming sheet 6 and is absorbed by the thread material 7. Thread material 7
Has shrinkage and elasticity. For this reason, as shown in FIG.
Erected, and three-dimensional gathers 5 'due to contraction in the longitudinal direction
Is formed, and the sanitary napkin 1 becomes a boat shape. Therefore, since the sanitary napkin 1 is not formed in a boat shape from the beginning, it can be easily fixed to shorts or the like at the time of wearing, and can be easily packaged and carried without any troublesome manufacturing. If there is absorption, a three-dimensional gather 5 'is formed to sufficiently prevent lateral leakage and the like. Although the liquid-permeable sheet portion 6a is provided on the skin contact side (outside), if the liquid-permeable sheet portion 6a is provided on the surface material side (inside), the liquid material is temporarily absorbed from the surface material 2. The wet back liquid of the body fluid
And the above effects are obtained.

In the above embodiment, the thread material is attached as shown in FIG. 3, but the present invention is not limited to this. 4 (a) and 4 (b) are sectional views showing another embodiment of the thread material attaching portion of the sanitary napkin according to the present invention, and the thread material 7 shown in FIG. The transparent sheet 6 is adhered to the surface. Also in this case, the same operation and effect as described above can be obtained regardless of whether the attachment surface of the thread material 7 is on the skin contact side or the surface material side. Further, as shown in FIG. 4B, only a part of the gather forming sheet 6 enclosing the thread material 7 is
a, and the other can be the liquid impermeable sheet 6b, and in this case, further operational effects can be obtained.

Further, in the above embodiment, as shown in FIG. 1, the thread material 7 is attached along the longitudinal direction along the free end of the gather forming sheet 6 and along the inclined width direction. It is not necessary to follow the installation position of the thread material in FIG. 1 as long as the installation is performed in the direction and the width direction. That is,
FIGS. 5A and 5B are plan views showing another aspect of the thread material attachment position of the sanitary napkin according to the present invention.
5A shows a thread material 7 attached to a gather forming sheet 6 in a substantially T-shape, and FIG.
Are mounted in a substantially U-shape. Even in such a configuration, when the three-dimensional gather forming body 5 absorbs the bodily fluid, it becomes three-dimensional gathers 5 ', and the sanitary napkin has a hull shape, and has the same operation and effect as described above. Although the sanitary napkin 1 is used in the above embodiment, the sanitary napkin 1 can be used for other absorbent articles. For example, it can be used for a pad for incontinent persons and, in some cases, a disposable diaper.

[0016]

As described above, the absorbent article according to the present invention has a three-dimensional gather forming body which is easy to mount and easy to manufacture and has no problem in the form of individual packaging. By forming hull-shaped three-dimensional gathers, side leakage such as menstrual blood can be sufficiently prevented.

[Brief description of the drawings]

1 (a) is a plan view of an absorbent article (sanitary napkin) according to the present invention, FIG. 1 (b) is a cross-sectional view of the sanitary napkin along a longitudinal direction, and FIG. 1 (c) is a width direction of the sanitary napkin. FIG.

2 (a) is a cross-sectional view along the longitudinal direction of the sanitary napkin after absorbing the bodily fluid of FIG. 1, and FIG. 2 (b) is a cross-sectional view along the width direction of the sanitary napkin after absorbing the bodily fluid of FIG. is there.

FIG. 3 is a sectional view of a thread material attaching portion used in the sanitary napkin of FIG. 1;

FIGS. 4A and 4B are cross-sectional views showing another embodiment of the thread material attaching portion of the sanitary napkin according to the present invention.

5 (a) and 5 (b) are plan views showing another aspect of the thread material attachment position of the sanitary napkin according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sanitary napkin 2 Surface material 3 Back material 4 Absorber 5 3D gather forming body 5 '3D gather 6 Gather forming sheet 6a Liquid permeable sheet 6b Liquid impermeable sheet 7 Thread material

──────────────────────────────────────────────────の Continued on front page (51) Int.Cl. ⁷ Identification code FI A61F 13/514

Claims (2)

(57) [Claims] 1. An absorbent article comprising a liquid-permeable front material, a back material, and an absorber provided therebetween, wherein a yarn material that contracts and exhibits elasticity after absorbing liquid is a gather forming sheet. A three-dimensional gather forming body integrally disposed with the sheet in a longitudinal direction and a width direction of the sheet, one side end of the sheet along the longitudinal direction is fixed to the surface material, and the other side end is a free end. A pair of three-dimensional gather formed bodies arranged so that the free end can stand up from the surface material surface due to the shrinkage and elasticity of the thread material after absorbing the liquid, respectively, on both sides in the longitudinal direction of the absorber. An absorbent article characterized by being provided on the surface material along the surface. 2. The absorbent article is a sanitary napkin, wherein the sanitary napkin has a stiffness of 1 g · cm to 50 g ·
The absorbent article according to claim 1, wherein the stress at 50% elongation of the yarn after liquid absorption is in the range of 5 g to 150 g in the range of cm.