JP2019217097A - Absorbent article - Google Patents

Abstract

To provide an absorbent article which is excellent in rate of absorption and wear feeling without ruining an advantage to use a fiber assembly composed of tow excellent in softness and flexibility.SOLUTION: An absorbent article 1 includes a liquid-permeable top sheet 10; a liquid-impermeable back sheet 20; and an absorber 30 arranged between the top sheet 10 and the back sheet 20. The absorber 30 has a fiber assembly 32 composed of tow, an absorbent core 31 mixed with fluff pulp 33 and high-absorbent polymer 34, and a carrier sheet 35 covering the absorbent core 31.SELECTED DRAWING: Figure 2

Description

  The present invention relates to absorbent articles such as light incontinence pads.

  In general, an absorbent article is composed of a liquid-permeable top sheet, a liquid-impermeable back sheet, and an absorber disposed between the top sheet and the back sheet, and thereby, such as urine and the like. Body fluid is absorbed by the absorber through the topsheet. Further, as an absorber, a form in which an absorbent core containing fluff pulp and a super absorbent polymer (also referred to as SAP) is wrapped with a carrier sheet such as crepe paper is widely known. . These absorbents are formed by laying fluff pulp short fibers and a superabsorbent polymer on a laying drum to form an absorbent core, and then wrapping the absorbent core in a carrier sheet.

  On the other hand, instead of a pile of fluff pulp short fibers, a tow (fiber bundle) composed of a filamentous long fiber web is spread (hereinafter, referred to as a fiber aggregate composed of tow) as an absorber. It has been proposed to use. By using a fiber aggregate made of tow instead of fluff pulp, an absorbent having excellent flexibility and flexibility can be obtained. In addition, by using an absorbent having excellent flexibility and flexibility, wearing an absorbent article under clothing can be made inconspicuous, and fit can be improved.

  As an absorbent article using an absorbent containing a fiber aggregate composed of a tow, for example, Patent Document 1 has an aggregate of filaments composed of a tow and a highly absorbent polymer, and other than the both sides of the crotch portion. An absorbent article using an absorber, characterized in that the main absorbent portion, which is a main absorbent portion, has a super absorbent polymer and the basis weight of the super absorbent polymer on both sides of the crotch portion is smaller than that of the main absorbent portion. Have been.

  Patent Literature 2 discloses an absorbent article provided with an absorber having a structure in which a long fiber web containing a superabsorbent polymer and a fluff pulp pile layer containing a superabsorbent polymer are stacked. .

JP 2007-268218 A JP 2007-144101 A

  However, in the absorbent article described in Patent Literature 1, since the absorbent uses only the fiber aggregate made of tow without using fluff pulp, the hydrophilicity of the fiber aggregate made of tow is low, and the absorbent itself is not used. Since the absorption rate is inferior to fluff pulp, when a large amount of urine is excreted at one time, there is a case where the urine cannot be completely absorbed and leakage occurs.

  Further, in the absorbent article described in Patent Document 2, since the absorbent has a structure in which the long fiber web and the fluff pulp fiber layer are stacked, the rigidity of the entire absorbent body is increased by the fluff pulp fiber layer. In addition, the flexibility and flexibility of the long-fiber web are impaired, and a good wearing feeling cannot be obtained.

  Therefore, the present invention has been made in view of the above problems, and the present invention has a good feeling of wearing without impairing the advantage of using a fiber assembly made of a tow that is excellent in flexibility and flexibility. An object of the present invention is to provide an absorbent article that maintains and has a good absorption rate.

  (1) An absorbent article according to the present invention includes a liquid-permeable topsheet, a liquid-impermeable backsheet, and an absorber disposed between the topsheet and the backsheet. Wherein the absorber has a fiber aggregate made of tow, fluff pulp, and an absorbent core into which a highly absorbent polymer is mixed, and a carrier sheet that covers the absorbent core.

  (2) In the above configuration (1), it is preferable that the fiber aggregate made of the tow, the fluff pulp, and the superabsorbent polymer are almost uniformly mixed into the absorbent core.

  (3) In the above configuration (1), the fiber aggregate made of the tow and the fluff pulp are almost uniformly mixed into the absorbent core, and the superabsorbent polymer is formed in the longitudinal direction and the width of the absorbent article. It is preferable that the dispersion density differs in any one of the directions.

  (4) In any one of the above constitutions (1) to (3), it is preferable that the basis weight of the fiber aggregate made of the tow is larger than the basis weight of the fluff pulp.

  (5) In any one of the above constitutions (1) to (4), it is preferable that constituent fibers of the fiber assembly made of the tow are fibers made of cellulose acetate.

  (6) In any one of the constitutions (1) to (5), the fluff pulp is preferably at least one of a hardwood kraft pulp and a softwood kraft pulp.

  Advantageous Effects of Invention According to the present invention, it is possible to provide an absorbent article having a good wearing feeling and a good absorption rate without impairing the advantage of using a fiber aggregate made of a tow having excellent flexibility and flexibility. Can be.

It is a top view of an absorptive article of this embodiment. Is _X 1 -X ₁ cross-sectional view of FIG. It is a longitudinal section of an absorptive core of a modification.

  Hereinafter, embodiments for carrying out the invention (hereinafter, referred to as embodiments) will be described in detail with reference to the drawings. The same reference numerals are given to the same elements throughout the description of the embodiments. In the description of the present specification, the longitudinal direction of the absorbent article 1 is a direction extending across the wearer when the absorbent article 1 is worn, and is a direction indicated by a symbol Y in the figure. Further, the width direction of the absorbent article 1 is a direction that is transverse or orthogonal to the longitudinal direction, and is a direction indicated by a reference sign X in the figure. Furthermore, in the description of this specification, the body-side surface refers to the surface arranged on the skin side of the wearer when worn, of the front and back surfaces of each member, and the clothing-side surface refers to the front and back surfaces of each member. Of these, the surface that faces the side opposite to the wearer's skin side when worn.

<Absorptive article>
First, the absorbent article 1 according to the present embodiment will be described in detail with reference to FIGS.
FIG. 1 is a plan view of the absorbent article 1 of the present embodiment. Figure 2 is a _X 1 -X ₁ cross-sectional view of FIG.

  As the absorbent article 1 according to the present embodiment, a light incontinence pad is exemplified, but is not limited thereto, and may be a light incontinence liner, a sanitary napkin, or another absorbent article.

  As shown in FIG. 1, an absorbent article 1 includes a liquid-permeable topsheet 10 disposed on a body-side surface, and a liquid-impermeable backsheet opposed to the topsheet 10 and disposed on a clothing-side surface. 20 and an absorber 30 disposed between the topsheet 10 and the backsheet 20. Thereby, the absorber 30 has a structure sandwiched between the top sheet 10 and the back sheet 20.

  It is preferable that the length of the absorbent article 1 in the longitudinal direction is 100 mm or more and 400 mm or less, and the dimension in the width direction is 30 mm or more and 110 mm or less. By adjusting the dimensions of the absorbent article 1 to the above range, the absorbent article 1 suitable for a light incontinence pad, a light incontinence liner, a sanitary napkin, or the like can be obtained.

[Top sheet]
The top sheet 10 allows body fluids to pass quickly toward the absorber 30, and is arranged to face the back sheet 20 with the absorber 30 interposed therebetween. Since the top sheet 10 is a sheet that comes into contact with the skin, it has a soft feel and does not irritate the skin, and is made of a hydrophilic nonwoven fabric, an open film such as an open polyethylene film, or a foam such as a urethane foam. It is formed from a film or a composite sheet obtained by laminating these films. The top sheet 10 may be a single layer or a laminate of a plurality of layers, and may have a large number of through holes for imparting dry touch properties.

  Further, as the hydrophilic nonwoven fabric having the above properties, synthetic fibers such as polypropylene and polyethylene, regenerated fibers such as rayon, natural fibers such as cotton, using a thermal bond method, an air-through method, a spunlace method, Those obtained by a known processing method such as a spun bond method can be used.

The basis weight of the top sheet 10 is preferably 13 g / m ² or more and 40 g / m ² or less from the viewpoint of workability and strength. To reduce irritation to the skin, a lotion, an antioxidant, an anti-inflammatory component, a pH adjuster, an antibacterial agent, a humectant, or the like may be applied to the top sheet 10.

[Back sheet]
As the back sheet 20 used in the present embodiment, a sheet material having liquid impermeability and having water blocking properties is used, but may have moisture permeability in order to prevent stuffiness. As a material of the back sheet 20 having such characteristics, for example, a plastic sheet having a small thickness such as a polyethylene sheet or a polyethylene laminated nonwoven fabric can be exemplified. The basis weight of the back sheet 20 is preferably 15 g / m ² or more and 60 g / m ² or less from the viewpoint of workability and strength.

  Although not shown, a pressure-sensitive adhesive layer for fixing the absorbent article 1 to underwear or the like when worn may be provided on the clothing-side surface of the back sheet 20. When the absorbent article 1 has a pressure-sensitive adhesive layer, the absorbent article 1 may have a release sheet for protecting the pressure-sensitive adhesive layer, and this release sheet is partially bonded to the packaging sheet of the absorbent article 1. May be.

[Absorber]
As shown in FIG. 2, the absorber 30 used in the absorbent article 1 of the present embodiment is formed in a substantially square or substantially rectangular shape in a plan view, and the thickness of the absorber 30 is such that the absorption speed is good. The thickness is preferably 1.5 mm or more and 6.0 mm or less so as not to impair the feeling of wearing. Further, it is preferable that the longitudinal dimension of the absorber 30 be 95 mm or more and 395 mm or less, and the width direction dimension be 25 mm or more and 105 mm or less.

  In addition, the absorber 30 has a fiber aggregate 32 made of tow, an absorbent core 31 into which fluff pulp 33 and a highly absorbent polymer 34 are mixed, and a carrier sheet 35 that covers the absorbent core 31 so as to wrap the absorbent core 31. I have.

  As described above, since the absorbent core 31 contains both the fiber aggregate 32 made of tow and at least the fluff pulp 33, the fiber aggregate 32 made of tow imparts flexibility and flexibility to the absorber 30. Owing to the excellent liquid diffusivity of the fluff pulp 33, the absorption speed can be improved.

  It is preferable that the fiber aggregate 32 and the fluff pulp 33 made of tow are almost uniformly mixed into the absorbent core 31. Thereby, uniform flexibility and flexibility can be imparted to the absorber 30, and body fluids such as urine can be uniformly diffused throughout the absorber 30.

  The fiber aggregate 32 made of tow is an aggregate of long fiber filaments obtained by opening the tow, and is converged so that the orientation directions of the long fibers are aligned. In the present embodiment, it is preferable to arrange the long fibers so that the orientation direction of the long fibers is the longitudinal direction of the absorbent article 1. For example, by opening a continuous filament tow and cutting it into an appropriate length, a fiber aggregate composed of a bundle of long fibers can be manufactured.

As the base material of the fiber assembly 32 made of tow, natural cellulose derived from cotton or the like, regenerated cellulose such as rayon, cellulose acetate, polyethylene, polypropylene, PET, or the like can be used. It is preferable to use natural cellulose, regenerated cellulose such as rayon, or cellulose acetate, and it is more preferable to use cellulose acetate which can easily obtain bulkiness and can impart flexibility and flexibility to the absorber 30.
The fineness of the fiber assembly 32 made of tow is not particularly limited, but from the viewpoint that the absorbent core 31 exhibits desired performance and has sufficient strength in use, for example, 0.1 dtex or more and 10 dtex. The following may be sufficient.

  In the fiber assembly 32 made of tow, since the entanglement between the fibers is weak, it is preferable to use a binder for the purpose of fusing and fixing the entanglement. As the binder, triacetin or the like can be used.

In the present embodiment, the basis weight of the fiber assembly 32 made of tow is 40 g / m ² or more and 300 g / m ² or less. When the basis weight of the fiber assembly 32 made of tow is in the above range, the fluff pulp 33 and the superabsorbent polymer 34 can be supported to the extent that the absorbability can be secured, and the absorbent 30 having excellent flexibility and flexibility can be supported. Can be obtained. When the basis weight of the fiber assembly 32 made of tow exceeds 300 g / m ² , the degree of compression when the thickness of the absorber 30 is reduced becomes large, and the original flexibility and the flexibility of the fiber assembly 32 made of tow are increased. It is not preferable because flexibility is impaired. Further, it is preferable that the basis weight of the fiber assembly 32 made of tow is not less than 60 g / m ^{2 and not} more than 200 g / m ² .

  As fluff pulp 33, wood pulp, synthetic fiber, polymer fiber, non-wood pulp, or the like can be mentioned as a flocculent fiber. Alternatively, it is preferable to use a softwood kraft pulp that has been opened, and it is more preferable to use a hardwood kraft pulp that has a shorter fiber length, is softer, and has a lower cost.

In the present embodiment, the basis weight of the fluff pulp 33 included in the absorbent core 31 is 30 g / m ² or more and 200 g / m ² or less. By setting the basis weight of the fluff pulp 33 included in the absorbent core 31 to the above range, the advantage of using the fiber aggregate 32 made of the tow having excellent flexibility and flexibility for the absorber 30 is not impaired. In addition, it is possible to maintain a good feeling of wearing and to improve the absorption speed of the absorber 30 as a whole. In other words, if the basis weight of the fluff pulp 33 is too large, the overall flexibility and flexibility of the absorber 30 will be reduced. Further, the basis weight of the fluff pulp 33 is preferably 40 g / m ² or more and 160 g / m ² or less.

  Further, in the present embodiment, the basis weight of the fiber aggregate 32 made of tow is preferably larger than the basis weight of the fluff pulp 33, and the basis weight ratio of the fluff pulp 33 to the fiber aggregate 32 made of tow is: More preferably, it is 0.6 or more and less than 1.0. Thereby, the advantage by using the fiber aggregate 32 made of the tow having excellent flexibility and flexibility can be reliably maintained.

  The superabsorbent polymer 34 is not particularly limited as long as it can absorb bodily fluids and prevent backflow. Sodium polyacrylate, polyaspartate, (starch-acrylic acid) graft copolymer And (acrylic acid-vinyl alcohol) copolymers, (isobutylene-maleic anhydride) copolymers, and saponified products thereof. Among them, sodium polyacrylate is preferred from the viewpoint of the amount of absorption per weight.

  In the present embodiment, the superabsorbent polymer 34 is formed such that the basis weight (that is, the dispersion density) differs in the width direction of the absorbent article 1. As shown in FIG. 2, the absorbent core 31 is positioned on one side (the left side in FIG. 2) in the width direction and has a dimension A in the width direction of 7.5 mm or more and 32.5 mm or less, and a region A in the width direction. A region B (the right side in FIG. 2) positioned on the other side and having a width dimension of 7.5 mm or more and 32.5 mm or less, and a region having a width direction of 10 mm or more and 40 mm positioned between the regions A and B. And the following region C. The basis weight of the superabsorbent polymer 34 in the region A and the basis weight of the superabsorbent polymer 34 in the region B are the same, and become larger than the basis weight of the superabsorbent polymer 34 in the region C. I have.

  In the present embodiment, the basis weight of the superabsorbent polymer 34 in the region A and the basis weight of the superabsorbent polymer 34 in the region B are the same, and the basis weight of the superabsorbent polymer 34 in the region C. Although not limited thereto, for example, the basis weight of the superabsorbent polymer 34 in the region A and the basis weight of the superabsorbent polymer 34 in the region B may be different. Also, the basis weight of both superabsorbent polymers 34 should be larger than the basis weight of superabsorbent polymer 34 in region C.

  As described above, the basis weight of the superabsorbent polymer 34 in the regions A and B located on both sides of the absorbent core 31 is smaller than the basis weight of the superabsorbent polymer 34 in the region C located in the center of the absorbent core 31. By increasing the size, the superabsorbent polymer 34 that has swollen by absorbing bodily fluids such as urine has a difference in swelling depending on the region, and a flow path of the body fluid due to the difference in swelling is formed at the boundary of each region, and the absorbent 30 The overall absorption speed is improved, and leakage of bodily fluids from both sides of the absorbent article 1 can be reliably suppressed.

Specifically, the basis weight of the superabsorbent polymer 34 in the region A and the region B is preferably 40 g / m ² or more and 450 g / m ² or less, and the basis weight of the superabsorbent polymer 34 in the region C. The amount is preferably from 0 g / m ^{2 to} 150 g / m ² .

The carrier sheet 35 may cover the entire absorbent core 31 or may cover the absorbent core 31 from above and below. By covering the absorbent core 31 with the carrier sheet 35, the shape of the absorbent core 31 can be maintained, and additionally, the superabsorbent polymer 34 can be prevented from leaking out of the absorber 30. Examples of the carrier sheet 35 include a tissue, an absorbent paper, a hydrophilic non-woven fabric such as a spun-bonded non-woven fabric and an air-laid non-woven fabric, and it is preferable to use a tissue from the viewpoint of liquid diffusibility, water retention, and cost. The basis weight is preferably 10 g / m ² or more and 40 g / m ² or less, more preferably 15 g / m ² or more and 20 g / m ² or less from the viewpoint of strength and feeling of wearing.

  It is preferable that the absorbent core 31 has at least two compressed grooves provided substantially parallel to the orientation direction of the constituent fibers of the fiber assembly 32 made of tow. By providing the above-described compressed grooves in the absorbent core 31, the absorption speed of the entire absorbent body can be further improved.

[Three-dimensional gather]
It is preferable that a solid gather is provided on the body side surface of the absorbent article 1 (not shown). The three-dimensional gather forms a confined space for bodily fluids together with the top sheet 10 so that leakage of bodily fluids can be prevented. It is preferable that the three-dimensional gather includes a three-dimensional gather sheet and a stretchable elastic member arranged along a free end of the three-dimensional gather sheet. As the elastic elastic member, a thread-shaped, string-shaped, or flat-shaped member made of natural rubber, synthetic rubber, polyurethane, or the like can be used as appropriate.

<Method for producing absorbent article>
The method for producing the absorbent article 1 is not particularly limited, and a conventionally known method can be adopted. For example, the backsheet 20, the absorber 30, and the topsheet 10 are laminated in this order from the clothing side, and the topsheet is laminated. It can be manufactured by fixing the backsheet 10 and the backsheet 20 over a part or the entire circumference using a hot melt adhesive, heat embossing, ultrasonic embossing, high frequency embossing, or the like. Then, after individually wrapping this in a package, it may be folded in three in the longitudinal direction and folded.

  As described above, the present invention has been described using the embodiments. However, it is needless to say that the technical scope of the present invention is not limited to the scope of the above embodiments, and various changes or improvements may be made to the above embodiments. It is clear to a person skilled in the art that is possible. It is apparent from the description of the claims that the embodiments with such changes or improvements can be included in the technical scope of the present invention.

(Modification)
Next, the absorbent core 31 of the modified example will be described in detail with reference to FIG.
FIG. 3 is a vertical cross-sectional view of the absorbent core 31 of the modified example.

  In the above embodiment, the superabsorbent polymer 34 of the absorbent core 31 is formed so that the dispersion density thereof is different in the width direction of the absorbent article 1, but is not limited thereto. They may be formed so that their dispersion densities are substantially the same (that is, they are almost uniformly mixed into the absorbent core 31).

  In the above-described embodiment, the superabsorbent polymer 34 of the absorbent core 31 is formed so as to have a different dispersion density in the width direction of the absorbent article 1, but is not limited thereto. For example, the absorbent article 1 may be formed so that the dispersion density differs in the longitudinal direction.

  In this case, as shown in FIG. 3, the absorbent core 31 is positioned at one end (the left side in FIG. 3) in the longitudinal direction and has a longitudinal dimension of 27.5 mm or more and 157.5 mm or less; A region E (right side in FIG. 3) positioned at the other end in the direction and having a longitudinal dimension of 27.5 mm or more and 157.5 mm or less, and a region between the region D and the region E and having a longitudinal dimension of 40 mm And a region F that is not less than 80 mm. The basis weight of the superabsorbent polymer 34 in the region D and the basis weight of the superabsorbent polymer 34 in the region E are the same, and are larger than the basis weight of the superabsorbent polymer 34 in the region F. I have.

  In the present embodiment, the basis weight of the superabsorbent polymer 34 in the region D and the basis weight of the superabsorbent polymer 34 in the region E are the same, and the basis weight of the superabsorbent polymer 34 in the region F. However, the present invention is not limited to this. For example, the basis weight of the superabsorbent polymer 34 in the region D may be different from the basis weight of the superabsorbent polymer 34 in the region E. Also, it is only necessary that the basis weight of the superabsorbent polymer 34 is larger than the basis weight of the superabsorbent polymer 34 in the region F.

  As described above, the basis weight of the superabsorbent polymer 34 in the regions D and E located at both ends of the absorbent core 31 is smaller than the basis weight of the superabsorbent polymer 34 in the region F located in the center of the absorbent core 31. By increasing the size, the superabsorbent polymer 34 that has swollen by absorbing bodily fluids such as urine has a difference in swelling depending on the region, and a flow path of the body fluid due to the difference in swelling is formed at the boundary of each region, and the absorbent 30 The overall absorption speed is improved, and the leakage of bodily fluids from both ends of the absorbent article 1 can be reliably suppressed.

Specifically, the basis weight of the superabsorbent polymer 34 in the region D and the region E is preferably 40 g / m ² or more and 450 g / m ² or less, and the basis weight of the superabsorbent polymer 34 in the region F. The amount is preferably from 0 g / m ^{2 to} 150 g / m ² .

DESCRIPTION OF SYMBOLS 1 Absorbent article 10 Top sheet 20 Back sheet 30 Absorber 31 Absorbent core 32 Fiber aggregate made of tow 33 Fluff pulp 34 Superabsorbent polymer 35 Carrier sheet

Claims (6)

A liquid-permeable top sheet, a liquid-impermeable back sheet, and an absorbent article including an absorber disposed between the top sheet and the back sheet,
The absorber,
An absorbent core into which a fiber assembly composed of tow, fluff pulp and super absorbent polymer are mixed,
And a carrier sheet covering the absorbent core. The absorbent article according to claim 1, wherein the fiber aggregate made of the tow, the fluff pulp, and the superabsorbent polymer are mixed almost uniformly into the absorbent core. The fiber aggregate made of the tow and the fluff pulp are almost uniformly mixed into the absorbent core,
The absorbent article according to claim 1, wherein the superabsorbent polymer has a different dispersion density in one of a longitudinal direction and a width direction of the absorbent article. 4. The absorbent article according to claim 1, wherein the basis weight of the fiber aggregate made of the tow is larger than the basis weight of the fluff pulp. 5. The constituent fiber of the fiber aggregate made of the tow is a fiber made of cellulose acetate. The absorbent article according to any one of claims 1 to 4, wherein the fiber is made of cellulose acetate. The said fluff pulp is at least one of a hardwood kraft pulp and a softwood kraft pulp. The absorbent article as described in any one of Claims 1 to 5 characterized by the above-mentioned.