JP2003038552A - Absorbent article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To decrease a sense of incongruity and to improve a sense of fitting while an absorbent article is used and to improve absorbing speed and scattering preventing effect of a humor by improving softness and cushioning properties of a thin absorbent body. SOLUTION: In the absorbent article 1 in which the absorbent body 4 is placed between a liquid-permeable surface sheet 3 and a liquid-impermeable back surface sheet 2, the absorbent body 4 is an absorbent body in which a pulp and a highly water-absorbing resin are main ingredients and which are formed into a sheet-like shape and a wavy processing in which recessed parts 4b, 4b... and projected parts 4a, 4a... continue along the longitudinal direction of the absorbent article 1 is applied in a region containing at least a humor discharging site. WC value (compression energy value) of the wavy processing region part measured by means of a KES compression testing machine is 0.25-1.5 gf.cm/cm<2> .

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to absorbent articles used for absorbent articles such as sanitary napkins, panty liners, incontinence pads for absorbing menstrual blood and vaginal discharge, and more particularly to air-laid nonwoven fabric. The present invention relates to an absorbent body that improves the softness and cushioning property of a thin absorbent body that uses the same, and that reduces discomfort during use to enhance wearability, and an absorbent article using the same.

[0002]

2. Description of the Related Art Since the introduction of body fluid absorbent articles such as sanitary napkins, panty liners and incontinence pads to the market, various improvements have been made for absorbent bodies using super absorbent polymers.

As is well known, super absorbent polymers have the property that they absorb water and swell when they come into contact with water to form a gel, and once they absorb water, they do not separate even if some pressure is applied.
Its water absorption capacity is tens to thousands of times larger than its own volume, showing an amazing water absorption capacity. The superabsorbent resin, although exhibiting the above-mentioned water absorption ability by itself, cannot exhibit the water absorption ability unless it is in a swelled state to some extent, and since the water absorption speed is slow, pulverized pulp, rayon, etc. It is mixed in the form of powder, crushed powder or pellets.

In recent years, absorbent articles of this kind have problems that they are bulky and thus are inconvenient to carry or have poor storability, and they are thin due to demands for efficient distribution and resource saving. It has come to be made compact and compact. Since it is not possible to reduce the amount of water absorption even if the absorber is made thin or compact, it is usually dealt with by increasing the content ratio of the super absorbent polymer, but if the content ratio of the super absorbent resin is raised too much. The so-called "gel blocking", in which the gap between the swollen water-absorbing polymer particles is extremely reduced, occurs and the desired water-absorbing power cannot be expressed. as a result,
Permeation of menstrual blood or the like is inhibited by the bond between the water-absorbing polymer particles, and a phenomenon in which the permeation-inhibited menstrual blood or the like flows back again and comes out can be seen.

Various methods for suppressing the gel blocking have been proposed, but at present, the content ratio of the superabsorbent resin to the total weight of the water absorbent material such as pulverized pulp and the superabsorbent resin is generally within 80%, preferably. It is often attempted to reduce the thickness to 50% or less and to apply a severe press to the absorber.

Further, as the content ratio of the super absorbent resin is increased and the fiber component is relatively reduced, there arises a problem that the absorbent body is likely to be twisted or broken.
To solve this problem, there have been proposed methods such as cross-linking cellulose of pulp with an appropriate cross-linking agent, adding a binder resin, mixing heat-meltable fibers and adhering fibers by heat treatment. ing.

[0007]

However, when the absorbent body is made thin by press working, the product density of the absorbent body (crushed pulp, etc.) is extremely increased, so that the water absorption capacity is lowered and The body becomes stiff and the wearer feels uncomfortable. Further, there are problems that wrinkles are formed to be large and that leakage easily occurs.

Further, in the case of the above-mentioned countermeasure against the twisting or cracking of the absorbent body, the body fluid absorbing ability of the fiber itself is lowered by the crosslinking treatment or the heat treatment, or the swelling property of the super absorbent polymer is hindered. There are problems that problems occur, that the water-absorbent resin is completely covered with the binder, which lowers the water-absorbing ability, and that the binder and heat-sealing increase the rigidity of the absorber and impair the wearing feeling.

Therefore, a first object of the present invention is to improve the softness and cushioning property of the thin absorbent body to reduce the uncomfortable feeling during use to improve the wearing feeling, and at the same time, the absorption rate of body fluid and the diffusion preventing effect. Is to raise.

The second problem is that in addition to the above problems,
This is to improve the strength and prevent the absorbent body from being twisted, cracked, or torn.

[0011]

In order to solve the above-mentioned first problem, the present invention according to claim 1 provides an absorbent article in which an absorbent body is interposed between a liquid-permeable top sheet and a liquid-impermeable back sheet. In the absorbent article, the absorbent body is a sheet-shaped absorbent body composed mainly of pulp and a superabsorbent resin, and is a recess along the longitudinal direction of the absorbent article in a region including at least a body fluid discharge site. And the convex portions are continuously corrugated, and the corrugated region has a WC value (compression energy value) of 0.25 to 0.25 measured by a KES compression tester.
There is provided an absorbent article having a weight of 1.5 gf · cm / cm ² .

According to a second aspect of the present invention, in an absorbent article in which an absorbent body is interposed between a liquid-permeable top sheet and a liquid-impermeable back sheet, the absorbent body is made of pulp, chemical fibers, and A sheet-shaped absorbent body containing a water-absorbent resin as a main component, wherein a region including at least a body fluid discharge site is subjected to corrugation processing in which concave and convex portions are continuous along the longitudinal direction of the absorbent article. In addition, there is provided an absorbent article having a WC value (compression energy value) of 0.25 to 1.5 gf · cm / cm ² measured by a KES compression tester in the corrugated region.

The present invention according to claim 3 provides the absorbent article according to any one of claims 1 and 2, wherein an apparent thickness of the corrugated region of the absorber is 0.5 to 3.0 mm. .

In the present invention according to claim 4, the absorber thickness before corrugation is 0.3 to 2.0 mm, and the apparent thickness after corrugation is 1.6 of the absorber thickness before corrugation. ~
The corrugated processing is performed so that it becomes 10 times.
An absorbent article according to any one is provided.

As a fifth aspect of the present invention, in the corrugated region of the absorber, the absorber thickness of the concave and convex portions is 0.3 to 2.0 mm, and the connection between the concave and convex portions is made. The absorber thickness of the portion is 0.1 to 1.8 mm, and the corrugation is performed so that the absorber thickness of the connecting portion is smaller than the absorber thickness of the concave portion and the convex portion. An absorbent article according to claim 1 is provided.

According to a sixth aspect of the present invention, the interval between the concave portions or the convex portions is 1.0 to 10 mm.
An absorbent article according to any one of 5 is provided.

According to a seventh aspect of the present invention, there is provided the absorbent article according to any one of the first to sixth aspects, in which the content of the superabsorbent resin is 10 to 60%.

The present invention according to claim 8 provides the absorbent article according to any one of claims 2 to 6, wherein the content of the chemical fiber is 5 to 30%.

According to a ninth aspect of the present invention to solve the second problem, a heat-fusible non-woven fabric made of chemical fibers is laminated on the upper and lower surfaces or the upper surface of the absorbent body, and the heat-fusible non-woven fabric is also formed. The absorbent article according to any one of claims 1 to 8, which is corrugated.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a partially cutaway perspective view of an absorbent article 1 according to the present invention.

The absorbent article 1 is mainly used for applications such as a panty liner, a sanitary napkin, a vaginal discharge sheet, and an incontinence pad. For example, as shown in FIG. 1, a liquid impermeable back sheet. 2 and the liquid permeable topsheet 3 between the absorbent body 4 or the absorbent body 4 as shown in FIG.
The absorbent body unit 6 composed of the crepe paper 5 surrounding it and the crepe paper 5 is interposed. Around the absorber 4, the liquid-impermeable backsheet 2 and the liquid-permeable topsheet 3 are joined by an adhesive means such as a hot melt adhesive.

The liquid-impervious back sheet 2 is made of a sheet material having at least water-blocking property such as polyethylene or polypropylene. A non-woven fabric sheet (in which case, the waterproof film and the non-woven fabric form a liquid-impermeable back sheet) can be used after interposing a substantially liquid-impervious property. In recent years, from the viewpoint of preventing stuffiness, those having moisture permeability tend to be preferably used. This water-impermeable / moisture-permeable sheet material is obtained by melt-kneading an inorganic filler in an olefin resin such as polyethylene or polypropylene to form a sheet, and then stretching the sheet uniaxially or biaxially A sheet is preferably used.

As the liquid-permeable surface sheet 3, a non-porous or perforated non-woven fabric, a porous plastic sheet or the like is preferably used. As the material fibers constituting the non-woven fabric, for example, synthetic fibers such as olefins such as polyethylene and polypropylene, polyesters, polyamides, etc., regenerated fibers such as rayon and cupra, and natural fibers such as cotton can be used. In addition, core-sheath type fibers and side-side fibers having a high melting point fiber as a core and a low melting point fiber as a sheath are used.
Composite fibers such as buy-side type fibers and split type fibers can also be preferably used.

As the processing method, a nonwoven fabric obtained by an appropriate processing method such as a spunlace method, a spunbond method, a thermal bond method, a meltblown method, a needle punch method, or the like can be used. Among these processing methods, the spunlace method is excellent in flexibility and drapability, and the thermal bond method is excellent in bulkiness and softness.

The absorber 4 interposed between the liquid-impermeable backsheet 2 and the liquid-permeable topsheet 3 is, for example, a mixture of pulp with a super absorbent resin, or pulp with chemical fibers. What is mixed with a super absorbent resin is used.

Examples of the pulp include those made of cellulosic fibers such as chemical pulp and molten pulp obtained from wood, and artificial cellulose fibers such as rayon and acetate, and softwood pulp having a longer fiber length than hardwood pulp. Is preferably used in terms of function and price. Further, as the manufacturing method, those manufactured by the airlaid method are suitable.

Examples of the highly water-absorbent resin include polyacrylate crosslinked products, self-crosslinked polyacrylic acid salts,
Acrylic ester-saponified product of vinyl acetate copolymer crosslinked product, isobutylene / true maleic anhydride copolymer crosslinked product,
Examples thereof include crosslinked polysulfonates and partially crosslinked water-swellable polymers such as polyethylene oxide and polyacrylamide. Among these, acrylic acid or acrylate based ones, which are excellent in water absorption amount and water absorption speed, are preferable. In the manufacturing process, the superabsorbent resin having the above water-absorbing performance can be adjusted in water absorbing power and water absorbing speed by adjusting the crosslinking density and the crosslinking density gradient. The content ratio of the super absorbent polymer is preferably 10 to 60%. When the content of the super absorbent polymer is less than 10%, it is not possible to provide sufficient absorption capacity, and when it exceeds 60%, the entanglement between pulp fibers is lost, and the sheet strength is lowered to cause breakage or cracking. Is likely to occur.

Examples of the chemical fibers include olefins such as polyethylene and polypropylene, polyesters,
Hydrophobic synthetic fibers such as polyamide type can be preferably used. The mixing of the chemical fibers is to provide the absorbent body 4 with flexibility by interposing between the hydrogen bonds of the pulps. The content of the chemical fiber is preferably 5 to 30%. When the content is less than 5%, it is not possible to give remarkable flexibility as compared with the case where no chemical fiber is mixed, and when the content exceeds 30%, the water absorption performance is lowered and the body fluid is retained. become unable.

In the present invention, in particular, the concave portions 4b, 4b and the convex portions 4 are formed in the absorbent article 4 along the longitudinal direction of the absorbent article.
a and 4a are continuous wavy processing,
A WC value (compression energy value) measured by a KES compression tester in the corrugated region is 0.25 to 1.5 gf · cm / cm ² is used. By performing the corrugated processing on the absorbent body 4, the flexibility in the width direction of the absorbent body is improved, and the cushioning property is given to the surface of the absorbent body, so that the discomfort at the time of mounting is eliminated. Further, the corrugated recesses 4b, 4b ... serve as damming grooves to prevent the diffusion of the body fluid, and the body fluid flowing into the recesses 4b, 4b. Then, it is quickly absorbed by the absorber 4 side.
Furthermore, when the absorbent body 4 is corrugated, even if the liquid-permeable surface sheet 3 is a non-woven fabric, the dry feeling is improved as compared with the conventional one, and when a porous plastic sheet is adopted. That tendency (dry feeling)
Will become more prominent at the same time.

The KES compression tester (manufactured by Kato Tech Co., Ltd.) is a tester for simulating the sensation felt when a human finger touches an object.
It is possible to measure compression hardness, compression recovery, etc. For measurement, sample speed: 0.01 cm / sec,
Compressed area: 2 cm ² , sensitivity: 2 (force meter 200 g / 10 v), compressive load: 50 gf / cm ² Compressed under the conditions of pressure and deformation amount, LC (compression hardness), WC (compression energy) )
And RC (compression recovery) are calculated.

First, the LC (compression hardness) is shown by [area of a + b] / [area of [Delta] ABC] in the correlation diagram between pressure and deformation amount shown in FIG. The compression hardness is evaluated as hard. The WC (compression energy) is represented by [area of a + b], and the larger the value, the easier the compression is evaluated. The final RC (compression recovery property) is represented by [area of b] / [area of a + b], and the closer the value is to 100%, the more the recovery is evaluated. Among these test items, it is preferable to use WC (compression energy) as an index for the softness that can be understood by sensory evaluation. The WC value (compression energy value) is 0.25 gf · c
When it is less than m / cm ² , the absorbent body 4 does not appear soft and the user still feels uncomfortable at the time of wearing. Also, WC
When the value (compression energy value) exceeds 1.5 gf · cm / cm ² , the absorber 4 is apt to be twisted or cracked, and the shape cannot be maintained.

In the transverse sectional view shown in FIG. 2, the apparent thickness T _K of the absorber 4 is preferably 0.5 to 3.0 mm. Since this absorber 4 is used as a thin absorber, it is desirable to set the upper limit of the thickness to 3 mm, and if it is too thick, the corrugation processability deteriorates.

Regarding the degree of corrugation, the thickness of the absorber before corrugation is 0.3 to 2.0 mm, and the apparent thickness after corrugation is 1.6 to the thickness of the absorber before corrugation.
It is desirable to perform the corrugated processing so as to be 10 times. If the thickness ratio is less than 1.6 times, the softness and cushioning property are not sufficiently imparted, and sufficient absorption rate of body fluid and diffusion preventing effect cannot be expected. Further, when the thickness ratio exceeds 10 times, the corrugation becomes difficult and the corrugated shape cannot be maintained in a product state.

Further, in the corrugation of the absorber 4, the absorber thicknesses t ₂ and t ₁ of the concave portions 4b, 4b ... And the convex portions 4a, 4a ... Are set to 0.3 to 2.0 mm, and the concave portion 4 is formed.
connection parts 4c, 4 for connecting the convex parts 4a, 4a.
The absorber thickness of c ... is 0.1 to 1.8 mm, and the connecting portion 4
It is desirable to perform corrugation processing so that the absorber thickness of c, 4c ... Is smaller than the absorber thickness of the recesses 4b, 4b. By making the absorber thickness of the connecting portions 4c, 4c ...
The portions c, 4c ... Are bent to be easily deformed and the flexibility is improved.

On the other hand, between the concave portions 4b, 4b or the convex portion 4
It is desirable to perform corrugation with a linear density such that the distance W between a and 4a is 1.0 to 10 mm. Distance between the concave portions or the convex portions W
When the thickness is less than 1.0 mm, the cushioning effect, the improvement of the body fluid absorption rate and the body fluid diffusion preventing effect cannot be expected, and
Tear easily occurs in the absorber 4. When the interval W between the concave portions or the convex portions exceeds 10 mm, the effects intended by the present invention such as the effect of imparting flexibility, the cushioning effect, the improvement of the body fluid absorption rate and the body fluid diffusion preventing effect cannot be expected.

It is desirable that the absorbent body 4 be surrounded by crepe paper 5 in order to maintain the shape and quickly diffuse menstrual blood and the like and prevent the menstrual blood and the like once absorbed from returning. Further, the planar shape of the absorbent body 4 may be an oval shape as shown in the figure, or may be a fit cut shape (gourd shape) to soften the contact with the crotch portion.

By the way, in the absorber 4, as shown in FIG.
As shown in (A), the heat-fusible non-woven fabric 7 made of chemical fibers is laminated on the upper and lower surfaces of the absorber 4, or as shown in FIG.
As shown in FIG. 2, a heat-fusible non-woven fabric 7 made of chemical fibers may be laminated on the upper surface, and corrugated with the heat-fusible non-woven fabric 7. The heat-fusible non-woven fabric 7 is used as the absorber 4
By integrally providing it on at least one surface side, the absorbent body 4 is given strength, and it is possible to effectively prevent twisting, cracking, breaking, and the like. Further, in the above embodiment, the corrugated processing is formed over almost the entire area of the absorbent body 4, but it may be formed at least in a region including the body fluid discharge portion.

In order to perform the corrugated processing on the absorber 4, as shown in FIG. 4, the corrugated roll 8 having a large number of circumferentially continuous convex stripes 8a on the roll surface, and the convex stripes. Anvil roll 9 having a groove 9a at a position corresponding to 8a
Are arranged so as to face each other, the absorbent strip 4 ′ is passed between both rolls 8 and 9, and the absorbent strip 4 ′ is continuously corrugated.

[0039]

As described above in detail, according to the inventions of claims 1 to 8, the softness and cushioning property of the thin absorber are improved to reduce the discomfort during use and to improve the wearing feeling. In addition, the absorption rate of body fluid and the diffusion prevention effect can be enhanced.

According to the invention of claim 9, in addition to the above effects, it is possible to improve the strength and prevent the absorbent body from being twisted, cracked or broken.

[Brief description of drawings]

FIG. 1 is a partially cutaway perspective view of an absorbent article 1 according to the present invention.

FIG. 2 is an enlarged transverse cross-sectional view of a main part of an absorber 4.

FIG. 3 is a diagram showing an embodiment in which a heat-fusible non-woven fabric 7 is laminated on the absorber 4.

FIG. 4 is a diagram of a corrugated processing on the absorber 4.

FIG. 5 is a correlation diagram between the pressure and the deformation amount, showing the results of the KES compression test.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Absorbent article, 2 ... Liquid-impermeable backsheet, 3 ... Liquid-permeable topsheet, 4 ... Absorber, 5 ... Crepe paper, 6 ... Absorber unit, 7 ... Heat-fusible non-woven fabric, 8 ... Wave Processing rolls, 9
... anvil roll

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁷ Identification symbol FI theme code (reference) B32B 5/02 (72) Inventor Ken Saeki 151-2 Atshara, Fuji-shi, Shizuoka F-term in Daio Sanitary Products Co., Ltd. (reference) 3B029 BA03 BA05 BA12 BD14 BF03 4C003 AA02 AA04 AA16 AA19 AA22 AA27 DA04 GA02 4C098 AA09 CC03 CC05 CC11 DD06 DD10 DD25 DD27 DD28 4F100 AJ05 AJ06 AK01D AK01E AK04 AK07 AK25 AR00A AR00B BA03 BA05 BA10A BA10B DD06C DD06D DD06E DG02C DG03C DG10 DG15D DG15E GB66 GB71 JD05A JD05B JD15C JK01 JK05C JK11 JL12D JL12E YY00C

Claims (9)

[Claims] 1. An absorbent article having an absorbent body interposed between a liquid-permeable top sheet and a liquid-impermeable back sheet, wherein the absorbent body is made of pulp and a superabsorbent resin as a main component in a sheet form. In the formed absorbent body, at least the region containing the body fluid discharge part is subjected to wavy processing in which concave and convex portions are continuous along the longitudinal direction of the absorbent article, and KES compression of the wavy processed area is performed. WC by testing machine
Value (compression energy value) is 0.25 to 1.5gf · cm / cm ²
Absorbent article characterized by being. 2. An absorbent article in which an absorbent body is interposed between a liquid-permeable top sheet and a liquid-impermeable back sheet, wherein the absorbent body contains pulp, chemical fiber and superabsorbent resin as main components. A sheet-shaped absorbent body, in which a region including at least a body fluid discharge part is subjected to corrugation processing in which recesses and projections are continuous along the longitudinal direction of the absorbent article, and the corrugated processing region WC value (compression energy value) by KES compression tester of 0.25 to 1.5
An absorbent article characterized by having gf · cm / cm ² . 3. The absorbent article according to claim 1, wherein an apparent thickness of the corrugated region of the absorber is 0.5 to 3.0 mm. 4. The absorber thickness before corrugation is 0.3 to 2.0.
The absorbent article according to any one of claims 1 to 3, wherein the absorbent article according to any one of claims 1 to 3 has a corrugated shape so that the apparent thickness after corrugated processing is 1.6 to 10 times the absorber thickness before the corrugated processing. . 5. The corrugated region of the absorber has an absorber thickness of 0.3 to 2.0 mm in the concave and convex portions, and a absorber thickness of a connecting portion connecting the concave and convex portions is 0. 1 ~
The absorbent article according to any one of claims 1 to 4, wherein the absorbent article has a thickness of 1.8 mm and is corrugated so that the absorber thickness of the connecting portion is smaller than the absorber thickness of the concave portion and the convex portion. 6. The interval between the concave portions or the convex portions is 1.0 to
The absorbent article according to claim 1, which has a length of 10 mm. 7. The content of the super absorbent resin is 10 to 60%.
The absorbent article according to any one of claims 1 to 6. 8. The absorbent article according to claim 2, wherein the chemical fiber content is 5 to 30%. 9. The heat-fusible non-woven fabric made of chemical fibers is laminated on the upper and lower surfaces or the upper surface of the absorber, and corrugated with the heat-fusible non-woven fabric. Absorbent article.