JPH11206807A - Disposable diaper - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a disposable diaper which is effective for preventing side leak and stuffiness, has good absorbency, and can save cost. SOLUTION: In a disposable diaper which has a liquid permeable surface sheet 1 of wide width, a liquid impermeable back surface sheet 2 of narrower width than the surface sheet 1, an absorber 3 placed between these sheets, side flaps 4 extending outwards from both longitudinal side edges of the absorber 3, and a pair of sterie gathers 9 formed near both side edges of the absorber 3, the side flaps 4 are formed by parts where the surface sheets 1 and 2 extend outwards from both longitudinal side edges of the absorber 3, cut lines are formed from the side edges to the vicinity of the absorber 3 around the boundary between the back side parts and the inside leg part 12 of the side flaps 4 and around the boundary between the front side part and the inside leg part 12 of the side flaps 4, and the side leg part is folded back on the absorber 3 so that the inside leg part 12 contacts the absorber 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disposable diaper, and more particularly to a disposable diaper that is effective in preventing side leakage and stuffiness, has good diffusion properties, and can reduce costs. is there.

[Prior art and problems]

Conventionally, a disposable diaper, which is one of absorbent articles, comprises an absorbent made of cotton-like pulp, a highly absorbent polymer or the like between a liquid-permeable top sheet and a liquid-impermeable back sheet. The configuration is arranged. The excrement is absorbed by the absorber through the topsheet. In this case, the absorber must receive the excrement and hold it without rewetting the skin. As an absorbent body, a mixture of a highly absorbent polymer and a cottony pulp alone or a cottony pulp placed thereon is known, but the absorption rate is low,
In addition, the return of excrement from the absorber to the surface (hereinafter, wet back) is large. When such an absorbent is used, it gives the user discomfort, and in the case of an infant, it also contributes to skin rash.

[0003] Various proposals have been made to solve these problems. In order to solve the problem of reduced absorption speed, it has been proposed to provide a second sheet between the top sheet and the absorber. There are things that are. For example, a net-shaped structural member made of a hydrophobic elastic foam (JP-A-59 / 1984)
JP-A-2280001), a sheet composed of hydrophilic synthetic fibers and hot-melt fibers (JP-A-60-198152), and a fiber assembly layer in which each fiber is fused at an intersection to maintain a web form (JP-A-63-1988). No. 220867) has been proposed for use as a second sheet. However, diapers such as these are effective in improving the absorption rate and wet back, but require a different material from the topsheet to form the second sheet, which requires a large amount of material, resulting in manufacturing costs. Goes up. In addition, most of the generally known diapers have side flaps cut off in order to reduce the width of the crotch in order to improve the fit of the crotch, so that the material is wasted.
In addition, since the back sheet and the top sheet are attached to the side flaps and the absorber is not arranged below the top sheet, sweat is not absorbed and easily accumulates and easily dries.
Furthermore, since the side flaps of the abdominal part and the dorsal part overlap on the abdomen of the wearer at the time of wearing, more stuffiness occurs. In order to prevent stuffiness, a known moisture-permeable film may be used for the back sheet in some cases, but only a slight effect is recognized.

[0004]

In view of such a situation, the present inventors have formed side flaps from a topsheet,
Further, a cut line is formed from the side edge to the vicinity of the absorber near the boundary between the back side of the side flap and the crotch and near the boundary between the abdomen and the crotch, and in the crotch portion,
A diaper whose folded part is folded so as to be in contact with the absorber is effective in preventing side leakage and stuffiness, has good diffusion properties, reduces the amount of material required for manufacturing, and reduces costs I found that I can do it.

An object of the present invention is to provide a disposable diaper which is effective in preventing side leakage and stuffiness, has good diffusion properties, and can reduce costs.

[0006]

SUMMARY OF THE INVENTION The present invention provides a liquid-permeable top sheet having a wide width, a liquid-impermeable back sheet having a width smaller than that of the top sheet, and an absorbent sheet disposed between these two sheets. Body, a side flap extending outward from both longitudinal edges of the absorber, and a pair of three-dimensional gathers formed near both edges of the absorbent body. Is formed by a portion extending outward from both side edges in the longitudinal direction of the absorber, near the boundary between the back side of the side flap and the crotch and near the boundary between the abdomen and the crotch and from the side edge near the absorber. So that the cut line is formed over, and the side flap of the crotch part has its folded part in contact with the absorber,
A disposable diaper characterized by being folded back to the absorber side. Further, the present invention is characterized in that the topsheet and the folded side flaps of the crotch portion have a hydrophilic area located on the absorber and a hydrophobic area located from the side to the outside of the absorber. It's a diaper.

BEST MODE FOR CARRYING OUT THE INVENTION

In the disposable diaper of the present invention, side flaps are formed by portions of the topsheet extending outward from both longitudinal edges of the absorbent body, and the side flaps are folded back toward the absorbent body at the crotch portion. The folded portion is arranged so as to be in contact with the absorber. In this case, in the topsheet and the folded side flap of the crotch portion, it is desirable that the region located on the absorber is hydrophilic and the region located from the side of the absorber to the outside is hydrophobic. With this configuration, the disposable diaper of the present invention has a folded side flap portion located below the topsheet and acts as a diffusion sheet, so urine that has passed through the topsheet is quickly absorbed. Spread to the body,
Good absorption performance is obtained, and it also prevents side leakage from the side edge of the crotch part.Furthermore, since the side flap part is formed of a topsheet, the abdomen part and the back part are The air permeability of the waist side edge is improved, and the stuffiness can be prevented.

As the surface sheet used in the present invention, a hydrophilic or hydrophobic nonwoven fabric or woven fabric made of polyester, polypropylene or the like is used. Natural fibers may be used, and the fibers can be manufactured from a wide range of materials such as a combination of synthetic fibers and natural fibers. In any case, since the topsheet is a portion that comes into direct contact with the skin, the topsheet may be soft and comfortable, and may be breathable. Since the side flap folded back to the absorber side of the central region and the crotch portion of the topsheet is arranged on the absorber,
It is preferable that the fibers are formed of hydrophilic fibers or have been subjected to a hydrophilization treatment so that the liquid can be quickly transmitted. Further, it is preferable that the both end regions in the longitudinal direction of the top sheet and the region outside from the side of the absorber are water repellent so that the liquid absorbed by the absorber does not seep out from the absorber. The topsheet does not need to be composed of a single sheet, but may be composed of a plurality of sheets such as a central topsheet and side topsheets. When the top sheet is composed of a plurality of sheets, each sheet may be made of a different material, or may be made of the same material. Also in this case, it is preferable that the portion arranged on the absorber is hydrophilic and the portion arranged from the side of the absorber to the outside is water-repellent.

The back sheet used in the present invention is:
Liquid impervious film such as polyethylene, made of a material that is woven or nonwoven bonded to the liquid permeable film,
There is no particular limitation as long as the moisture in the absorbent does not seep out of the diaper. Further, it may be embossed in a pattern to give a cloth-like appearance, or may be further matte-finished. In the case where a film is used, a known moisture-permeable film which is permeable to water vapor only while being impermeable may be used, which is preferable because it prevents stuffiness.

The absorbent used in the present invention is made from known absorbent materials commonly used in conventional disposable diapers and other absorbent articles. That is, floc pulp,
It is formed from a single-layer or multi-layer mat made of absorbent fibers such as rayon and wrapped by a hydrophilic sheet. Then, the superabsorbent polymer is uniformly mixed in each mat or disposed in layers between the mats. Alternatively, 3 to 60% by weight of a heat-fusible substance may be mixed with the cotton-like pulp and thermocompression-bonded. As floc pulp,
It is a fiber having a fiber length of 5 mm or less obtained by defibrating a chemical pulp sheet or a mechanical pulp sheet with a crusher. The pulp raw material is not limited to conifers, and hardwoods, straws, bamboos, kenafs and the like are also applicable. The amount of the pulp used varies depending on the intended absorber, for example, depending on whether the pulp is used alone, used in a plurality of layers, or used in combination with other absorbents, but is generally 50 to 400 g.
/ M ² .

The superabsorbent polymer includes starch-based polymers,
Cellulose type and synthetic polymer type are mentioned. That is, a starch-acrylic acid (salt) graft copolymer, a saponified product of starch-ethyl acrylate graft copolymer, a saponified product of starch-methyl methacrylate graft copolymer, and a saponified product of starch-acrylonitrile graft copolymer Product, saponified product of starch-acrylamide graft copolymer, saponified product of starch-acrylonitrile 2-acrylamide-2-methylpropanesulfonic acid graft copolymer, acrylic acid (salt) polymer, poly (acrylic acid) Examples include crosslinked products of ethylene oxide, sodium carboxymethylcellulose, and crosslinked products of polyvinyl alcohol-maleic anhydride reactant. Of these, those which absorb urine, body fluid and water at least 20 times their own weight, and polyacrylic Sodium acid-based ones from the point of absorption performance It is also suitable. The amount of the superabsorbent polymer used is 10 parts by weight per 100 parts by weight of the dry cotton-like pulp.
５００500 parts by weight, preferably 15-300 parts by weight, with such amount of superabsorbent polymer being substantially uniformly distributed in the floc. When the superabsorbent polymer absorbs and swells, the particles have minimal interference with each other,
It rarely forms a permeation barrier due to continuous contact, and permeates and absorbs urine and body fluid in three-dimensional directions.

In the present invention, the three-dimensional gathers are formed by band-shaped side sheets which are separate members from the top sheet and the back sheet.

The material of the side sheet is a hydrophilic or hydrophobic non-woven fabric, woven fabric, porous plastic film or the like or a liquid-impermeable film or a laminate thereof. The woven fabric and the non-woven fabric are made of polypropylene. Polyethylene, polyester, nylon or a composite fiber composed of two or more components such as polyester, polypropylene, polyethylene and nylon may be used. In particular, a composite fiber of polyester / polyester, polyester / polyethylene and polypropylene / polyethylene is desirable from the viewpoint of strength. However, there is no particular limitation.

The elastic body used in the present invention is natural,
A thread-like, cord-like, or flat-shaped member made of synthetic rubber, urethane, or the like is used depending on the installation position. The disposition of the elastic member is fixed to the sheet by an adhesive.

As the adhesive used in the present invention, a hot melt adhesive is advantageously used. In addition, a water-soluble glue such as starch or CMC (carboxymethylcellulose) or an adhesive having a high fluidity is used. Agents can be used.

The shape of the absorber used in the present invention is not particularly limited, such as an hourglass, a rectangle, and a T-shape, and may be any shape as long as it fits into a crotch.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the disposable diaper of the present invention will be described in detail with reference to the drawings, but the present invention is not limited to these. FIG. 1 is a partially cutaway plan view of a disposable diaper of the present invention. In FIG. 1, the diaper used is
Liquid permeable top sheet 1 and liquid impermeable back sheet 2
And an absorber 3 disposed between the two sheets, a side flap 4 formed by a portion of the back side 11 and the abdomen 13 of the diaper where the top sheet 1 extends, and both longitudinal edges of the diaper. And a portion of the crotch portion 12 inside the cut line 6 of the side flap 4 is folded back toward the absorber, so that the folded portion 7 comes into contact with the absorber 3. Is disposed between the topsheet 1 and the absorber 3. Also, in the drawing,
The cut line 6 of the side flap 4 is a straight line, but may be a curved line as long as the cut line 6 fits around the leg.

FIG. 2 shows the disposable diaper shown in FIG.
It is sectional drawing cut | disconnected along X 'line. In FIG.
Absorber 3 is arranged on back sheet 2, and folded portion 7 of a side flap is arranged between absorber 3 and top sheet 1. Further, a three-dimensional gather 9 is formed by a side sheet at a side edge portion of the absorber 3, and a stretchable elastic body 8 is arranged in an extended state at a free edge of the three-dimensional gather 9, and the free edge is formed by a contraction action thereof. Standing up.

FIG. 3 shows the disposable diaper shown in FIG.
It is sectional drawing cut | disconnected along the Y 'line. In FIG.
An absorber 3 is arranged between the top sheet 1 and the back sheet 2, and a side flap 4 is formed at a portion where the top sheet 1 extends outward from a side edge of the absorber 3. The three-dimensional gathers 9 arranged on the side edges of the absorber 3 have their free edges joined to the topsheet 1 on the absorber, and do not rise upward.

FIG. 4 is a cross-sectional view showing an example different from FIG. 2 and cutting the disposable diaper shown in FIG. 1 along the line XX '. In FIG. 4, the folding point area 10 of the side flap is located outside the side edge of the back sheet 2,
Further, between the side flaps of the turning point area 10, the leg elastic members 14 are arranged. The leg-surrounding elastic body 14 can be configured by arranging one or two or more elastic bodies in a straight line or in a curved line. When two or more elastic bodies are arranged, the elastic bodies can be arranged in parallel or non-parallel to each other.

[0021]

As described above, the disposable diaper of the present invention is effective in preventing stuffiness because the back flap and the abdomen side flap are formed only of the topsheet. Also, the top sheet forming the side flaps,
Since it is folded back on the absorber at the crotch part and acts as a diffusion sheet, it has good diffusivity, is effective in improving absorption and preventing leakage, and the amount of material required for production has been reduced, significantly Cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a partially cutaway plan view of a disposable diaper of the present invention.

FIG. 2 is a sectional view taken along line X-X 'of the disposable diaper of FIG.

3 is a sectional view taken along line Y-Y 'of the disposable diaper of FIG.

FIG. 4 is a sectional view taken along line XX ′ of the disposable diaper of FIG. 1 showing another embodiment different from FIG. 2;

[Explanation of symbols]

 1. Liquid permeable surface sheet 2. 2. Liquid-impermeable back sheet Absorber 4. Side flaps 5. Fastening tape 6. Score line 7. Folded part of side flap Elastic elastic body 9. Solid gathers 10. Turn point area 11. Dorsal side 12. Inseam 13. Ventral part 14. Elastic around the leg

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Ma Suzuki 19-2 Ars Kamakura A-301 Ueki 19-2, Kamakura City, Kanagawa Prefecture

Claims (2)

[Claims] 1. A wide liquid-permeable top sheet, a liquid-impermeable back sheet narrower than the top sheet, an absorber disposed between these two sheets, and a longitudinal direction of the absorber. In a disposable diaper having side flaps extending outward from both side edges and a pair of three-dimensional gathers formed near both side edges of the absorbent body, the side flaps are formed such that the topsheet is formed on both longitudinal edges of the absorbent body. A cut line is formed from the side edge to the vicinity of the absorber near the boundary between the back side and the crotch and near the boundary between the abdomen and the crotch of the side flap, and A disposable diaper characterized in that a side flap of a crotch portion is folded back toward the absorber so that the folded portion comes into contact with the absorber. 2. The folded side flap of the topsheet and the crotch portion is characterized in that a region located on the absorber is hydrophilic and a region located from the side of the absorber to the outside is hydrophobic. The disposable diaper according to claim 1.