JP7279286B2 - absorbent article - Google Patents

Description

The present invention relates to absorbent articles.

Absorbent articles such as light incontinence pads, underpants-type paper diapers, and tape-fastened paper diapers are composed of a liquid-permeable top sheet, a liquid-impermeable back sheet, and an absorbent body disposed between the two sheets. ing. As a result, body fluids such as urine pass through the top sheet and are absorbed by the absorbent member, and are prevented from leaking to the outside by the back sheet.
Also, an absorbent article has been developed in which both the top sheet and the back sheet are liquid-permeable, and urine and the like can be absorbed from both sides.
Such absorbent articles have been devised in various ways in order to improve absorbency of bodily fluids, improve wearer's wearing comfort, prevent leakage, and the like.

For example, Patent Literature 1 discloses an absorbent article in which nonwoven fabrics are arranged on both sides of an absorbent layer as an absorbent article capable of absorbing urine and the like from both the front and back surfaces.
Further, Patent Document 2 discloses a structure in which an absorber penetrating portion penetrating from the surface side to the back side is formed in the absorber, and the top sheet and the back sheet are joined directly or via a wrapping material of the absorber. disclosed.

Japanese Utility Model Laid-Open No. 2-130627 JP 2010-240896 A

In an absorbent article that can absorb urine from both the front side and the back side, as described in Patent Document 1, the purpose is to prevent leakage by supplementing the absorption amount of the disposable diaper worn. Depending on the state of incontinence, the pattern of incontinence, etc., there are demands such as "I want to have the urine absorbed repeatedly" or "I want to keep it comfortable by reducing regurgitation after urination." On the other hand, there are requests such as "I want to increase the total absorption amount by transferring urine to the lower diaper that is used repeatedly" or "I want to absorb as much as possible with the double-sided pad itself and not soil the lower diaper". There is also
However, in the case of the technique described in Patent Document 1, since it is a structure in which nonwoven fabrics are simply arranged on both sides of the absorbent layer, it is possible to sufficiently absorb excrement such as urine and prevent liquid return or repeated absorption. Quantity is difficult to secure.
Moreover, even in the case of the technique described in Patent Document 2, it cannot be said that liquid return prevention and absorption amount are particularly sufficient.
As described above, if the liquid return and absorption amount are insufficient, the wearer's skin is always wet and may feel uncomfortable.

The present invention has been made in view of the above circumstances, and is an absorbent article that is used over a disposable diaper to be worn, wherein the front and back surfaces are liquid-permeable, and the absorption capacity is maintained while maintaining the absorption capacity of the absorbent article. To provide an absorbent article which is excellent in dry feeling and liquid return on the face side surface, and which can suppress migration of excrement such as urine to a paper diaper to be worn.

As a result of intensive research, the inventors of the present invention have found that the above problems can be solved by providing a perforated film having a specific structure between the top sheet and the absorbent body and between the absorbent body and the back sheet. and completed the present invention.

That is, the present invention includes a liquid-permeable topsheet arranged on the skin-contacting side, a liquid-permeable backsheet arranged on the non-skin-contacting side, and a liquid-permeable backsheet arranged between the topsheet and the backsheet. comprising a first apertured film between the topsheet and the absorbent body, and a second apertured film between the absorbent body and the backsheet In the first perforated film, the pore diameter on the top sheet side is larger than the pore diameter on the absorbent body side, and in the second perforated film, the pore diameter on the absorbent body side is greater than the pore diameter on the back sheet side. In plan view, the area of the first perforated film is 80% or more and 100% or less of the area of the absorber, and the area of the second perforated film is greater than the area of the first perforated film. 30% or more and 70% or less of the area of the absorbent article.

Both the first perforated film and the second perforated film preferably have a pore diameter of 0.3 mm or more and 1.5 mm or less and a number of pores of 50 per cm ² or more.

In the first perforated film, the absolute value of the difference between the pore diameter on the top sheet side and the pore diameter on the absorbent body side is 0.03 mm or more and 0.15 mm or less, and the second perforated film, The absolute value of the difference between the pore diameter on the absorbent body side and the pore diameter on the back sheet side is preferably 0.03 mm or more and 0.15 mm or less.

The number of pores of the second porous film on the absorbent body side is preferably 30% or more and 70% or less of the number of pores on the top sheet side of the first porous film.

It is preferable that the pore diameter of the second perforated film on the absorber side is 30% or more and 70% or less of the pore diameter of the first perforated film on the top sheet side.

The porosity of the second perforated film on the absorbent body side is preferably 30% or more and 70% or less of the porosity of the first perforated film on the top sheet side.

A liquid diffusion sheet may be provided between the first porous film and the absorbent body.

According to the present invention, the absorbent article is used over a disposable diaper to be worn, and the front and back surfaces are liquid-permeable, and while maintaining the absorption amount, the surface on the skin side has a dry feeling and a liquid. It is possible to provide an absorbent article that is excellent in rehydration and that can suppress migration of excrement such as urine to a paper diaper worn.

1 is a plan view of an absorbent article of the present invention; FIG. FIG. 2 is a back view of the absorbent article of the present invention; FIG. 2 is a cross-sectional view taken along line YY in FIG. 1; FIG. 2 is a cross-sectional view taken along the line XX in FIG. 1; It is a cross-sectional view of a first apertured film. FIG. 4 is a cross-sectional view of a second apertured film;

Embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which are given for the purpose of illustration and are not intended to limit the invention. In addition, the same code|symbol is attached|subjected to the same element through the whole description of embodiment.

In addition, in the description of this specification, "when the absorbent article is worn" means at least one of when the absorbent article is worn and after the absorbent article is worn. The longitudinal direction of the absorbent article is the direction that spans the front and back of the wearer when the absorbent article is worn, and is the direction indicated by symbol Y in the drawings. Further, the width direction of the absorbent article is a direction that is transverse or perpendicular to the longitudinal direction, and is the direction indicated by symbol X in the drawings. Furthermore, the skin-contacting surface is the surface of the front and back surfaces of each member such as an absorbent body, which is arranged on the wearer's skin side when worn, and the non-skin-contacting surface is each member such as an absorbent body. Of the front and back sides of the , the side facing away from the wearer's skin when worn. Body fluids refer to liquids excreted from the body to the outside of the body, such as urine, blood, and water in loose stools. Furthermore, examples of absorbent articles include, but are not limited to, light incontinence pads, pants-type paper diapers, and tape-fastened paper diapers, regardless of whether they are for babies or adults. may

[Absorbent article]
FIG. 1 is a plan view of an absorbent article 10 according to an embodiment of the present invention, viewed from the top sheet 20 side. As shown in FIG. 1, the absorbent article 10 includes a liquid-permeable topsheet 20 arranged on the skin-contacting surface and a liquid-permeable backsheet arranged on the non-skin-contacting side facing the topsheet 20. 70 and an absorbent body 50 disposed between the topsheet 20 and the backsheet 70 .
In addition, the absorbent article 10 of this embodiment includes the first perforated film 30 between the top sheet 20 and the absorbent body 50, and the second perforated film 60 between the absorbent body 50 and the back sheet 70. Prepare. Further, a liquid diffusion sheet 40 is provided between the first perforated film 30 and the absorbent body 50 .
The absorbent article 10 of the present embodiment has perforated films on both the skin-contacting side and the non-skin-contacting side, and can absorb body fluids such as urine from both sides.

The dimension in the longitudinal direction Y of the absorbent article 10 is preferably 100 mm or more and 800 mm or less, and the dimension in the width direction X is preferably 50 mm or more and 500 mm or less. By adjusting the dimensions of the absorbent article 10 within the above range, the absorbent article 10 suitable for light incontinence pads, pants-type disposable diapers, tape-fastened disposable diapers, and the like can be obtained.
Details of each component will be described below.

(top sheet)
The liquid-permeable top sheet 20 is formed from a liquid-permeable base material that allows body fluids to move to the absorbent body 50 . Examples of liquid-permeable substrates include nonwoven fabrics such as air-through nonwoven fabrics, thermal bonded nonwoven fabrics, spunbond nonwoven fabrics, composite nonwoven fabrics laminated with thermal bond/spunbond, foamed films such as urethane foam, or laminated films of these. A composite sheet is mentioned.
In addition, the top sheet 20 may be embossed or perforated on the surface in order to improve liquid permeability. As a method for applying these embossing and perforating processes, known methods can be implemented without limitation. In order to reduce irritation to the skin, the top sheet 20 may contain a lotion, an antioxidant, an anti-inflammatory ingredient, a pH adjuster, an antibacterial agent, a moisturizing agent, and the like.

The basis weight of the top sheet 20 is preferably 18 g/m ² or more and 40 g/m ^{2 or} less in terms of strength, processability, and liquid return amount.

(back seat)
The liquid-permeable backsheet 70 is a liquid-permeable base that allows an appropriate amount of body fluid retained by the absorbent body 50 to migrate to another absorbent article such as a disposable diaper that is also used on the non-skin-contacting surface. formed from wood. Examples of liquid-permeable substrates include nonwoven fabrics such as air-through nonwoven fabrics, thermal bonded nonwoven fabrics, spunbond nonwoven fabrics, composite nonwoven fabrics laminated with thermal bond/spunbond, foamed films such as urethane foam, or laminated films of these. A composite sheet is mentioned.

From the viewpoint of strength and workability, the basis weight of the backsheet 70 is preferably 18 g/m ² or more and 40 g/m ² or less.

(Absorber)
In the absorbent article 10 of the present embodiment, as shown in FIG. 1, the longest width dimension _L40 in the longitudinal direction Y of the absorbent body 50 is preferably 100 mm or more and 800 mm or less, and is 150 mm or more and 500 mm or less. is more preferred. In addition, the longest dimension _W40 in the width direction of the absorbent body 50 is preferably 50 mm or more and 500 mm or less, and more preferably 70 mm or more and 105 mm or less.
Further, the absorbent body 50 in the absorbent article 10 of the present embodiment has a two-layer structure composed of an upper layer absorbent body positioned on the skin contact side and a lower layer absorbent body positioned on the non-skin contact side. Alternatively, a carrier sheet may be arranged between the upper layer absorbent body and the lower layer absorbent body to form a three-layer structure.

－Absorbent fiber－
The absorbent body 50 preferably contains absorbent fibers as a base material and a superabsorbent polymer (SAP).
Absorbent fibers may be those generally used in absorbent articles such as sanitary napkins, paper diapers, and incontinence pads. can be mentioned. Among these, fluff pulp is preferably used from the viewpoint of absorbability. Examples of fluff pulp include wood pulp (for example, bleached softwood kraft pulp (N-BKP) such as southern pine and Douglas fir), synthetic fiber, resin fiber, non-wood pulp, etc., which are defibrated into cotton. can. When fluff pulp is used as the absorbent fiber as the base material of the absorbent body 50, the basis weight of the absorbent fiber is preferably 100 g/m ² or more and 800 g/m ² or less, and 325 g/m ² or more and 615 g. /m ² or less is more preferable. As a result, more bodily fluids can be absorbed without impairing the feel of the skin.

－Super Absorbent Polymer－
As the superabsorbent polymer of the absorbent body 50, any polymer can be used as long as it can absorb bodily fluids and prevent backflow, such as sodium polyacrylate, polyaspartate, and (starch-acrylic acid) graft copolymer. , (acrylic acid-vinyl alcohol) copolymer, (isobutylene-maleic anhydride) copolymer and saponified products thereof. Among these, the sodium polyacrylate type is preferable from the viewpoint of the absorption amount per weight.

The basis weight of SAP contained in the absorbent body 50 is preferably 240 g/m ² or more and 450 g/m ² or less, more preferably 245 g/m ² or more and 445 g/m ² or less. Within the above numerical range, gel blocking in the absorbent body 50 can be prevented, and a large amount of body fluid can be absorbed in the absorbent body 50 .
In addition, in the absorbent body 50, the weight of superabsorbent polymer/weight of fluff pulp×100 (%), which is the ratio of the weight of superabsorbent polymer to the weight of fluff pulp, is 40% or more and 120% or less. , and more preferably 50% or more and 100% or less.

In the absorbent body 50, the absorbent fibers and the SAP may be formed by mixing SAP particles in the absorbent fibers, or may be an SAP sheet in which the SAP particles are fixed between the absorbent fibers. For the purpose of preventing leakage of SAP particles and stabilizing the shape of the absorbent 50, the absorbent 50 may be wrapped in a carrier sheet. The base material of the carrier sheet may be any material as long as it is hydrophilic, and examples thereof include hydrophilic nonwoven fabrics such as tissues, absorbent paper, and air-laid nonwoven fabrics. When a plurality of carrier sheets are provided, the substrates of the plurality of carrier sheets may be the same or different.

(Perforated film)
As shown in FIGS. 3 and 4, the absorbent article 10 of this embodiment includes a first perforated film 30 having pores between the top sheet 20 and the absorbent body 50. and the liquid-permeable backsheet 70, the second perforated film 60 is provided.
The first perforated film 30 preferably has liquid permeability such that body fluid such as urine moves to the absorbent body 50 .
In addition, the second perforated film 60 preferably has liquid permeability such that body fluids such as urine can move to the back sheet 70 .

-area-
In the absorbent article 10 of the present invention, the area of the first perforated film 30 is 80% or more and 100% or less of the area of the absorbent body 50 in plan view, and the area of the second perforated film 60 is It is 30% or more and 70% or less with respect to the area of the first perforated film 30 .
Here, the "area of the first perforated film" is a value obtained from the length L ₃₀ in the Y direction and the length W ₃₀ in the X direction of the first perforated film 30, as shown in FIG. , L ₃₀ ×W ₃₀ .
The "area of the second perforated film" is a value obtained from the Y-direction length L ₆₀ and the X-direction length W ₆₀ of the second perforated film 60, as shown in FIG. It is represented by L ₆₀ ×W ₆₀ .
Furthermore, as shown in FIG. 1, the “absorbent body area” is a value obtained from the length L ₅₀ in the Y direction and the length W ₅₀ in the X direction of the absorbent body 50. L ₅₀ ×W ₅₀ expressed.

Since the first perforated film 30 and the second perforated film 60 have the sizes as described above, the double-sided absorbent pad can compensate for the partial absorbency that is the original role of the double-sided absorbent pad, and the repeated absorption is excellent. In addition, liquid return can be suppressed.

-Pore diameter, number of holes, porosity ratio-
In the _absorbent article 10 of the present invention _, as shown in FIG. 6, in the second perforated film 60, the perforation diameter D _60a on the absorber 50 side is larger than the perforation diameter D _60b on the backsheet 70 side.
Here, the "aperture diameter" is the diameter of three arbitrarily selected apertures obtained by photographing the surfaces of the first apertured film 30 and the second apertured film 60 with a 3D microscope (VR-3100) manufactured by Keyence Corporation. is the average value of the
In this way, by setting the size of the pores on the top sheet 20 side and the back sheet 70 side within the above range, the surface feels good on the skin, and body fluids such as urine are quickly wetted and spread in the vertical direction and absorbed. Therefore, leakage can be prevented, and liquid return can be prevented.
Furthermore, by setting the size of the pores on the top sheet 20 side and the back sheet 70 side within the range described above, body fluids such as urine are prevented from migrating to the back sheet 70, and body fluids such as urine are suppressed. can be absorbed by the absorbent body 50 as much as possible, the absorbent body 50 can be effectively used, and as a result, migration to the lower paper diaper can be suppressed.

Both the first perforated film 30 and the second perforated film 60 have a perforation diameter of 0.3 mm or more and 1.5 mm or less on both the front and back sides, and the number of perforations is 50 per cm ² or more. is preferred.
By setting it as such a range, urine etc. can be easily absorbed and excellent in diffusibility.

Furthermore, as shown in FIG. 5, the absolute value of the difference between the pore diameter _D30a on the top sheet 20 side and the pore diameter _D30b on the absorbent body 50 side of the first perforated film 30 is 0.03 mm or more and 0.03 mm or more. 15 mm or less, and the absolute value of the difference between the pore diameter D _60a on the absorber 50 side and the pore diameter D _60b on the back sheet 70 side of the second perforated film 60 is 0.03 mm or more and 0.15 mm or less. Preferably.
By setting the difference in pore diameter between the first perforated film 30 and the second perforated film 60 within the above range, the surface feels good on the skin, and body fluids such as urine are quickly wetted and spread vertically and absorbed, preventing leakage. and can prevent liquid return.

The number of pores of the second porous film 60 on the absorbent body 50 side is preferably 30% or more and 70% or less of the number of pores on the top sheet 20 side of the first porous film 30 .
The pore diameter of the second perforated film 60 on the absorber 50 side is preferably 30% or more and 70% or less of the pore diameter of the first perforated film 30 on the top sheet 20 side.

Moreover, the porosity of the second perforated film 60 on the absorber 50 side is preferably 30% or more and 70% or less with respect to the porosity of the first perforated film 30 on the top sheet 20 side.
Here, "the porosity of the first perforated film 30 on the top sheet 20 side" is defined as the total perforated area of the surface 30a of the first perforated film 30 on the top sheet 20 side/the total perforated area of the first perforated film. It is a value obtained by multiplying the area by 100 (%).
In addition, "the porosity of the second perforated film 60 on the absorber 50 side" is defined as the total perforated area/the area of the second perforated film on the surface 60a of the second perforated film 60 on the absorber 50 side. It is a value obtained by multiplying by 100 (%).

By setting the number of pores, the diameter of the pores, and the aperture ratio of the second perforated film 60 to the relationship described above with respect to the first perforated film 30, body fluids such as urine quickly wet and spread in the vertical direction. Since it is absorbed, leakage can be prevented, and liquid return can be prevented.
Furthermore, body fluids such as urine can be suppressed from moving to the back sheet 70, and body fluids such as urine can be absorbed by the absorbent body 50 as much as possible. It is possible to suppress the transition to the paper diaper on the side.

- basis weight -
From the viewpoint of strength and workability, the basis weight of the first perforated film 30 and the second perforated film 60 is preferably 20 g/m ² or more and 60 g/m ² or less, more preferably 23 g/m ² or more and 30 g/m 2 or more. It is more preferably ² or less.

Excellent strength, workability, liquid permeability, and liquid diffusibility by setting the pore diameter, the number of pores, and the basis weight of the first perforated film 30 and the second perforated film 60 within the above ranges. , and reversal can be suppressed.

The first perforated film 30 and the second perforated film 60 in the present invention can be produced by embossing holes through a material such as a film having no holes.

－Material－
The material of the first perforated film 30 and the second perforated film 60 is preferably polyethylene or polypropylene, and more preferably polyethylene from the viewpoint of softness.

(liquid diffusing sheet)
As shown in FIGS. 3 and 4, the space between the first perforated film 30 and the absorbent body 50 improves the liquid diffusibility of the absorbent article 10 and reduces the hardness of the first perforated film 30. It is preferable to arrange the liquid-diffusing sheet 40 in order to suppress it and improve the touch. The base material of the liquid-diffusing sheet 40 may be any material that has a faster permeation rate of body fluids than the top sheet 20 and quickly diffuses the body fluids into the absorbent body 50. For example, a hydrophilic nonwoven fabric, particularly an air-through nonwoven fabric, is preferable. The liquid diffusion sheet 40 preferably has a thickness of 0.1 mm or more, and a basis weight of 10 g/m 2 or more and 60 g/m 2 or less, more preferably 15 g/m 2 or more and 40 g/m 2 or less. When the thickness is less than 0.1 mm, or the basis weight is less than 10 g/m 2 and greater than 60 g/m 2 , liquid such as urine cannot be sufficiently diffused over the entire upper surface of the absorbent body 50 . Moreover, the shape of the liquid-diffusing sheet 40 is preferably a shape that can completely cover the surface of the absorbent body 50 so that body fluids are diffused all over the absorbent body 50 .

(Three-dimensional gather)
In the absorbent article 10, a pair of three-dimensional gathers having an elastic member for three-dimensional gathers are provided on the top sheet 20 along the longitudinal direction of the absorbent article 10 in order to prevent lateral leakage of bodily fluid excreted by the wearer. You may prepare. The outer ends of the three-dimensional gathers in the width direction of the absorbent article 10 are fixed to the back sheet 70, the inner ends are fixed to the top sheet 20, and the center is a free end that is not fixed to the top sheet 20. Gathered sheets are provided. By providing the three-dimensional gathers elastic member along the longitudinal direction, the three-dimensional gathers can stand upright and can be deformed according to the body shape of the wearer. As the three-dimensional gather elastic member, for example, a polyurethane thread, a band-like polyurethane film, a thread-like or band-like natural rubber, or the like is used. Nonwoven fabrics such as spunbonded nonwoven fabrics, meltblown nonwoven fabrics, spunbond/meltblown/spunbond laminated composite nonwoven fabrics, and the like are used.

Although the present invention has been described using the embodiments, it goes without saying that the technical scope of the present invention is not limited to the scope described in the above embodiments and examples. It is obvious to those skilled in the art that various modifications or improvements can be made to the above embodiments. In addition, it is clear from the description of the scope of the claims that forms with such modifications or improvements can also be included in the technical scope of the present invention.

10 Absorbent Article 20 Top Sheet 30 First Perforated Film 40 Liquid Diffusion Sheet 50 Absorber 60 Second Perforated Film 70 Back Sheet

Claims (7)

It has a liquid-permeable topsheet arranged on the skin-contacting side, a liquid-permeable backsheet arranged on the non-skin-contacting side, and an absorbent body arranged between the topsheet and the backsheet. An absorbent article,
A first apertured film is provided between the top sheet and the absorbent body,
A second perforated film is provided between the absorbent body and the backsheet,
In the first perforated film, the perforation diameter on the top sheet side is larger than the perforation diameter on the absorbent body side,
In the second perforated film, the perforation diameter on the absorber side is larger than the perforation diameter on the backsheet side,
In plan view, the area of the first perforated film is 80% or more and 100% or less of the area of the absorber, and the area of the second perforated film is equal to the area of the first perforated film. 30% or more and 70% or less of the absorbent article. 2. The method according to claim 1, wherein each of the first perforated film and the second perforated film has a perforation diameter of 0.3 mm or more and 1.5 mm or less and a perforation number of 50 per cm ² or more. absorbent article. The absolute value of the difference between the top sheet side pore diameter and the absorber side pore diameter of the first perforated film is 0.03 mm or more and 0.15 mm or less, and the second perforated film, 3. The absorbent article according to claim 1, wherein the absolute value of the difference between the pore diameter on the absorbent body side and the pore diameter on the backsheet side is 0.03 mm or more and 0.15 mm or less. 3. Any one of claims 1 to 3, wherein the number of pores of the second porous film on the absorbent body side is 30% or more and 70% or less of the number of pores on the top sheet side of the first porous film. Absorbent article according to paragraph. 5. Any one of claims 1 to 4, wherein the pore diameter of the second perforated film on the absorbent body side is 30% or more and 70% or less of the pore diameter of the first perforated film on the top sheet side. absorbent article. 6. Any one of claims 1 to 5, wherein the porosity of the second perforated film on the absorbent body side is 30% or more and 70% or less with respect to the porosity of the first perforated film on the top sheet side. Absorbent article according to paragraph. 7. The absorbent article according to any one of claims 1 to 6, further comprising a liquid-diffusing sheet between said first porous film and said absorbent body.

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