JP2022041041A - Absorbent article - Google Patents

Abstract

To provide an absorbent article which has excellent wear feeling and fitness and excellent absorption performance.SOLUTION: An absorbent article 50 includes a top sheet 10, an absorber 20, and a back sheet 30. The absorber 20 has a high absorbent sheet 16 which is provided with a substrate nonwoven fabric 11 having a napped surface 11a where a plurality of napped fibers 11x are erected and a non-napped surface 11b, a high absorbent polymer 12 fixed and supported between the napped fibers 11x, and a hydrophilic sheet 13 covering the same. The high absorbent sheet 16 has a three-layer pseudo laminated structure including a first sheet part A, a second sheet part B, a third sheet part C and a fourth sheet part D folded with the non-napped surface 11b of the substrate nonwoven fabric 11 inside along a longitudinal direction of a middle part in a width direction, and is further provided with a first adhesion part 14 and a second adhesion part 15 in which respective SAP fixing supporting areas of the first sheet part A, the second sheet part B, and the fourth sheet part D partially overlap one another in a thickness direction, and fixes parts near both ends 16a, 16b in the width direction of the high absorbent sheet 16.SELECTED DRAWING: Figure 3

Description

The present invention relates to an absorbent article.

The absorbent article generally comprises a liquid-permeable top sheet, a liquid-impermeable back sheet, and an absorber arranged between them, and absorbs body fluid such as urine that has permeated the top sheet. It is absorbed and retained by the body. There are various types of absorbent articles, regardless of whether they are for adults or infants, depending on the application, such as tape-type disposable diapers, pants-type disposable diapers, urine absorbing pads, and light incontinence pads.

Conventionally, as an absorber, a fluff pulp absorber in which a fluff pulp and a super absorbent polymer (hereinafter, also referred to as “SAP”) are combined is generally used. However, for the purpose of further improving the wearing feeling, appearance, touch, etc. of the absorbent article, and further reducing the reversion of body fluids such as urine, two non-woven fabrics and a hot melt adhesive placed between them are used. Various absorbent articles using a highly absorbent sheet (hereinafter, also referred to as “SAP sheet”) containing the SAP particles fixed by the above as an absorber have been proposed.

In Patent Document 1, the facing surfaces are arranged to face each other, and the facing surfaces extend in the longitudinal direction between the first and second nonwoven fabrics, which are the adhesive-coated surfaces, and the adhesive-coated surfaces of the first and second nonwoven fabrics, and stripes. A plurality of SAP layers arranged in a shape are provided, and the adhesive is intermittently applied in the region facing the SAP layer on the adhesive-coated surface of the second nonwoven fabric, and the SAP layers are applied on both sides in the width direction of the SAP layer. A SAP sheet in which an adhesive is continuously applied in the longitudinal direction is disclosed on each of the adhesive-applied surfaces of the first and second nonwoven fabrics that directly face each other without intervening.

Patent Document 2 includes first and second absorbers disposed on one side and the other side in the width direction between the top sheet and the back sheet, and each of the first and second absorbers has two sheets. Disclosed is an absorbent article comprising a non-woven fabric and a SAP sheet containing SAP particles arranged between them, and having a laminated structure extending in the longitudinal direction and folded back at the first and second folds facing each other in the width direction. ing. Further, Patent Document 2 further includes a third absorber containing two nonwoven fabrics and SAP particles arranged between them, and the third absorber is arranged on the wearer's skin side of the first and second absorbers. The absorbent article has been disclosed.

Japanese Unexamined Patent Publication No. 2006-158676 JP 2013-42882 (Claim 1, Claim 5)

Since the SAP sheet used in Patent Documents 1 and 2 and many other absorbent articles has poor compressibility in the thickness direction, the wearer feels the rugged and hard feel of the SAP particles and the cured product of the hot melt adhesive on the skin. It is easy to feel, the feeling of wearing and the fit are greatly reduced, and the feeling of discomfort when wearing is increased. Further, in many SAP sheets, by fixing SAP particles to a non-woven fabric with a hot melt adhesive, SAP particles are present at a high density on the surface thereof, and as a result, a space for the SAP particles to absorb body fluid and expand. Is reduced. Therefore, the conventional SAP sheet is not sufficiently satisfactory in terms of the diffusivity of the body fluid, the absorption rate (particularly, the absorption rate after repeated absorption), and the absorbability.

An object of the present invention is to provide an absorbent article having a highly absorbent sheet, having a good wearing feeling and a good fit, and having excellent diffusivity and absorption rate of body fluid.

As a result of intensive research to solve the above problems, the present inventor has used an absorber having a conventional three-layer pseudo-laminated structure by bending a SAP sheet having a predetermined structure in the width direction. We have found that an absorbent article that meets the purpose can be obtained, and have completed the present invention. That is, the present invention relates to the following absorbent article.

(1) An absorbent article comprising a liquid-permeable top sheet, a liquid-impermeable back sheet, and an absorber arranged between them.
The absorber is
A base non-woven fabric having a raised surface on which a plurality of raised fibers are erected and a non-raised surface,
A highly absorbent polymer fixedly supported between the raised fibers on the raised surface of the substrate nonwoven fabric, and
It has a highly absorbent sheet comprising a hydrophilic sheet covering the raised surface on which the highly absorbent polymer of the substrate nonwoven fabric is fixedly supported.
The highly absorbent sheet is
It has a laminated structure including four first to fourth sheet portions bent along the longitudinal direction in the middle of the width direction and with the non-raised surface of the substrate nonwoven fabric inward.
The first sheet portion is located closest to the skin of the wearer, and one end in the width direction is one end in the width direction of the highly absorbent sheet.
The second seat portion is located on the most non-skin side of the wearer and faces the first seat portion in the thickness direction, and one end and the other end in the width direction are the fourth seat portion and the third seat portion, respectively. Connected to
The third sheet portion rises from the other end in the width direction of the second sheet portion in the thickness direction and is connected to the other end in the width direction of the first sheet portion.
The fourth sheet portion is located between the first sheet portion and the second sheet portion in the thickness direction, and the other end in the width direction is the other end in the width direction of the highly absorbent sheet.
The fixation-supporting region of the highly absorbent polymer in the first sheet portion, the fixation-supporting region of the highly-absorbent polymer in the second sheet portion, and the fixation of the highly-absorbent polymer in the fourth sheet portion. The overlapping region where the supported region overlaps in the thickness direction and the overlapping region,
A first adhesive portion for fixing the first sheet portion and the fourth sheet portion in the vicinity of one end in the width direction of the highly absorbent sheet, and
An absorbent article further comprising a second adhesive portion for fixing the second sheet portion and the fourth sheet portion in the vicinity of the other end in the width direction of the highly absorbent sheet.
(2) The absorbent article according to (1) above, wherein the widthwise dimension of the overlapping region is 10% or more and 95% or less of the widthwise dimension of the second sheet.
(3) The absorbent article according to (1) or (2) above, wherein the hydrophilic sheet has a basis weight of 15 g / m ² or more and 80 g / m ² or less.
(4) The absorbent article according to any one of (1) to (3) above, wherein the hydrophilic sheet has a bending stiffness of 0.015 gf · cm ² / cm or more and 0.080 gf · cm ² / cm or less.
(5) The absorbent article according to any one of (1) to (4) above, wherein the substrate nonwoven fabric has a basis weight of 20 g / m ² or more and 80 g / m ² or less.
(6) The absorbent article according to any one of (1) to (5) above, wherein the substrate nonwoven fabric is an air-through nonwoven fabric, and the thickness of the fibers constituting the air-through nonwoven fabric is 1.6 dtex or more and 14 dtex or less.
(7) The absorbent article according to any one of (1) to (6) above, wherein the basis weight of the highly absorbent polymer in the highly absorbent sheet is 100 g / m ² or more and 600 g / m ² or less.

According to the present invention, there is provided an absorbent article having a highly absorbent sheet, having a good wearing feeling and a good fit, and having excellent diffusivity of body fluid and absorption rate.

It is a schematic plan view which shows the structure of the absorbent article which concerns on 1st Embodiment. It is _a schematic cross-sectional view in the width direction in the X1 _- X1 cutting line shown in FIG. It is a schematic cross-sectional view which shows the structure of the absorber in the absorbent article shown in FIG. It is a schematic cross-sectional view which shows the structure of the absorber of another embodiment. It is a schematic perspective view which shows the structure of the substrate nonwoven fabric in an absorber. It is a schematic cross-sectional view which shows the structure of the highly absorbent sheet in an absorber.

In the present specification, the wearing of the absorbent article means a state in which the absorbent article is attached to the body before and after the absorption of the body fluid. In the absorbent article, the longitudinal direction is the direction indicated by Y in the figure, which extends to the front and back of the body through the crotch portion of the wearer when the absorbent article is worn on the body, and the width direction is the longitudinal direction. The direction is orthogonal to each other and is indicated by X in the figure, and the thickness direction is the direction in which the constituent members are laminated and indicated by Z in the figure. The skin side surface is the surface that comes into contact with the wearer's skin and the surface that faces the skin when the absorbent article is worn, and the non-skin side surface is the surface that comes into contact with the wearer's clothes or faces the clothes. be. Body fluid refers to the liquid discharged from the body such as urine, blood, and water in loose stool.

<Absorbable article>
Hereinafter, the absorbent article 50 according to the first embodiment will be described with reference to the drawings. 1 and 2 show the absorbent article 50. 3 and 4 show absorbers 20 and 20A, respectively. FIG. 5 shows the substrate nonwoven fabric 11. FIG. 6 shows the highly absorbent sheet 16. These drawings do not specify the shape, size, size relationship, etc. of each component in the absorbent article 50.

The absorbent article 50 of the present embodiment can be used as various absorbent articles for babies and adults, and examples thereof include a light incontinence pad, a urine absorbing pad, a pants-type disposable diaper, and a tape-stopping disposable diaper. Various types of disposable diapers as outerwear and absorbent articles 50 as innerwear may be combined. The lengthwise dimension and the widthwise dimension of the absorbent article 50 are not particularly limited, but are, for example, a range of 100 mm or more and 800 mm or less, and a range of 50 mm or more and 500 mm or less. By adjusting the dimensions of the absorbent article 50 to the above range, various forms of the absorbent article can be easily obtained.

The absorbent article 50 shown in FIGS. 1 and 2 has a liquid-permeable top sheet 10 located on the skin side and a liquid-impermeable back sheet 30 arranged opposite to the top sheet 10 and located on the non-skin side. And an absorber 20 arranged between the top sheet 10 and the back sheet 30, and a pair of three-dimensional gathers 40 provided on the skin-side surface of the top sheet 10.

According to the present embodiment, first, a substrate nonwoven fabric 11 having a raised surface 11a on which a plurality of raised fibers 11x are erected and a SAP fixing supporting layer 17 in which a highly absorbent polymer 12 is fixedly supported between the raised fibers 11x. And a hydrophilic sheet 13 covering the SAP fixation supporting layer 17, and the highly absorbent sheet 16 containing no fluff pulp is bent to form a predetermined three-layer pseudo-laminated structure, whereby the amount corresponding to three layers is obtained. The substrate non-woven fabric 11 having excellent body fluid diffusivity and cushioning property and the hydrophilic sheet 13 having excellent body fluid diffusivity diffuse the body fluid and suppress gel blocking, so that the body fluid is absorbed even after being absorbed multiple times. Absorption rate is maintained at the same high level as when the body fluid is absorbed for the first time.
Second, the high-absorbent sheet 16 has a predetermined three-layer pseudo-laminated structure, and the first adhesive portion 14 and the second adhesive portion 15 are provided near both ends 16a and 16b in the width direction of the high-absorbent sheet 16. Then, the SAP fixation-supporting layer 17 is sealed, and the highly absorbent polymer 12 in the SAP fixation-supporting layer 17 is prevented from falling off. As a result, the amount of the hot melt adhesive required for fixing and supporting the highly absorbent polymer 12 in the SAP fixing and supporting layer 17 is reduced, and the absorbent body 20 becomes softer.
Third, the three-layer pseudo-laminated structure in which one high-absorbency sheet 16 is bent can be manufactured by one manufacturing facility for the high-absorbency sheet 16, and has good operability such as operating speed. On the other hand, stacking three layers of SAP sheets online requires separate equipment for each layer, and there are many problems in terms of cost, installation location, and operability such as operating speed.

Hereinafter, each of the sheet-shaped or plate-shaped constituent members will be described in more detail in the order of the top sheet 10, the absorber 20, the back sheet 30, and the three-dimensional gather 40. These constituent members may have a three-dimensional shape other than a sheet shape and a plate shape.

<Top sheet>
The top sheet 10 is a liquid-permeable sheet-like member that allows body fluid to quickly pass toward the absorber 20, and is arranged so as to face the back sheet 30 with the absorber 20 interposed therebetween. Since the top sheet 10 may come into contact with the wearer's skin, a base material that has a soft feel and does not irritate the skin is preferable. Examples of the base material include a hydrophilic sheet, a composite non-woven fabric which is a laminate of the same or different types of hydrophilic sheets, an open film such as an open polyethylene film, and a foamed film such as polyethylene foam and urethane foam. Examples of the hydrophilic sheet include air-through non-woven fabrics, thermal bond non-woven fabrics, and spunlaced non-woven fabrics made of synthetic fibers made of synthetic resins such as polypropylene and polyethylene, recycled fibers such as rayon, and natural fibers such as cotton. Examples include spunbonded non-woven fabric.

The surface of the top sheet 10 may be embossed or perforated according to a known method from the viewpoint of improving the liquid permeability. From the viewpoint of reducing irritation to the skin, the top sheet 10 may contain one or more of lotions, antioxidants, anti-inflammatory components, pH regulators, antibacterial agents, moisturizers and the like. The basis weight of the top sheet 10 is, for example, in the range of 15 g / m ² or more and 40 g / m ² or less from the viewpoint of strength, workability and liquid return amount. The shape of the top sheet 10 is not particularly limited, and may be any shape that covers a part or all of the absorber 20 required for guiding the body fluid to the absorber 20 so as not to leak.

<First Embodiment of Absorber>
The absorber 20 is sandwiched between the top sheet 10 and the back sheet 30, and absorbs and retains body fluid such as urine that has permeated the top sheet 10, for example. As shown in FIGS. 3 and 4, the absorber 20 is configured by using a highly absorbent sheet (hereinafter, also referred to as “SAP sheet”) 16 that does not contain absorbent fibers such as fluff pulp.

As shown in FIG. 6 and the like, the highly absorbent sheet 16 includes a substrate nonwoven fabric 11 having a raised surface 11a on which a plurality of raised fibers 11x are erected and a non-brushed surface 11b on which the raised fibers 11x are not erected, and a substrate nonwoven fabric. The highly absorbent polymer 12 that is fixedly supported between the raised fibers 11x of the raised surface 11a of 11 to form the SAP fixed supporting layer (hereinafter, also referred to as “SAP layer”) 17, and the hydrophilicity that covers the substrate nonwoven fabric 11 and the SAP layer 17. Includes sheet 13 and.

In the absorber 20, as shown in FIG. 3 and the like, the highly absorbent sheet 16 is bent along the longitudinal direction at three intermediate portions in the width direction and with the non-raised surface 11b of the substrate nonwoven fabric 11 inward. It is configured in a three-layer pseudo laminated structure including four sheet portions, one sheet portion A, a second sheet portion B, a third sheet portion C, and a fourth sheet portion D. The three intermediate portions of the high-absorbency sheet 16 that form creases in the width direction are located at positions separated from each other in the width direction. In the present embodiment, the first sheet portion A, the third sheet portion C, the second sheet portion B, and the fourth sheet portion D are connected in this order in the width direction to form one highly absorbent sheet 16.

The first seat portion A is located closest to the skin of the wearer, one end in the width direction is the width direction end 16a of the high absorption sheet 16, and the other end in the width direction is connected to the third seat portion C. The second seat portion B is located on the most non-skin side of the wearer and faces the first seat portion A in the thickness direction of the absorber 20, and one end and the other end in the width direction are the fourth seat portion D and the third seat portion D and the third, respectively. It is connected to the seat portion C. The third sheet portion C rises from the other end in the width direction of the second sheet portion B in the thickness direction of the absorber 20 and is connected to the other end in the width direction of the first sheet portion A. By making the third sheet portion C have the above-mentioned configuration, a three-layer pseudo laminated structure by a method of bending is realized. The fourth sheet portion D is located between the first sheet portion A and the second sheet portion B in the thickness direction, and the other end in the width direction is the other end 16b in the width direction of the high absorption sheet 16. In this way, a three-layer pseudo-laminated structure is obtained in which the first sheet A, the fourth sheet D, and the second sheet B are laminated in this order in the thickness direction. In FIG. 3, one end and the other end in the width direction are the left and right ends with respect to the paper surface, respectively.

Further, the widthwise dimensions of the first sheet portion A, the second sheet portion B, the third sheet portion C, and the fourth sheet portion D depend on the width of the hydrophilic sheet 13 and the folding width of the absorber 20. It can be selected as appropriate. Here, the widthwise dimension of each sheet portion may be replaced with the widthwise dimension of the fixed carrier region (a part of the SAP layer 17) of the SAP of each sheet portion. In the present embodiment, the first sheet portion A, the second sheet portion B, and the fourth sheet portion D have the following relationship.

In the three-layer pseudo laminated structure of the present embodiment, the SAP fixation-supporting region in the first sheet portion A (a part of the SAP layer 17 near one end 16a in the width direction of the SAP sheet 16) and the second sheet portion B. The fixed holding region of SAP (a part of the SAP layer 17 near the middle part in the width direction of the SAP sheet 16) and the fixed holding region of SAP of the fourth sheet part D (the SAP layer near the other end 16b in the width direction of the SAP sheet 16). There is an overlapping region that overlaps with (a part of 17) in the thickness direction (FIG. 3). The widthwise dimension (maximum width) X of the overlapping region is a range of 10% or more and 95% or less or 50 of the widthwise dimension Y of the second sheet portion B (or the fixed carrier region of SAP in the second sheet portion B). It is in the range of% or more and 95% or less. Hereinafter, the ratio (X / Y) of the width direction dimension X and the width direction dimension Y is also referred to as an overlap ratio. If the overlap ratio is less than 10%, the amount of SAP in the central part of the absorber 20 tends to be small and the amount of absorption tends to decrease, and if it exceeds 95%, there is a space for fixing the widthwise end of the SAP sheet 16 of the absorber 20. There is a tendency for SAP to drop out due to lack. Here, the width direction dimension X is from one end 16a to the other end 16b when the three-layer pseudo laminated structure is seen through from the upper surface and one end 16a and the other end 16b of the SAP sheet 16 are placed on the same plane (virtual surface). Width dimension up to. The width direction dimension Y is the width direction dimension of the second sheet portion B, and more strictly, the width direction dimension from the crease with the fourth sheet portion D to the crease with the third sheet portion B.

As shown in FIG. 3, the absorber 20 having the three-layer pseudo laminated structure of the present embodiment has a first adhesive portion 14 and a second adhesive portion 15 mainly made of a hot melt adhesive.
The first adhesive portion 14 fixes the non-skin side surface of the first sheet portion A and the skin side surface of the fourth sheet portion D in the vicinity of one end 16a in the width direction of the highly absorbent sheet 16. In a preferred embodiment, the first adhesive portion 14 closes the non-skin side surface of the hydrophilic sheet 13 of the first sheet portion A and the skin side surface of the hydrophilic sheet 13 of the fourth sheet portion D so as to close the SAP layer 17. The highly absorbent sheet 16 is fixed in the vicinity of one end 16a in the width direction.

The second adhesive portion 15 fixes the skin side surface of the second sheet portion B and the non-skin side surface of the fourth sheet portion D in the vicinity of the other end 16b in the width direction of the high absorption sheet portion 16. In a preferred embodiment, the second adhesive portion 15 closes the non-skin side surface of the substrate nonwoven fabric 11 of the second sheet portion B and the non-skin side surface of the hydrophilic sheet 13 of the fourth sheet portion D so as to close the SAP layer 17. The highly absorbent sheet 16 is fixed near the other end 16b in the width direction.

That is, the first adhesive portion 14 and the second adhesive portion 15 are fixed so that the first sheet portion A is fixed at one end and the second sheet portion B is fixed at the other end with respect to both ends of the fourth sheet portion D in the width direction. An adhesive structure is provided. By providing this adhesive structure in the three-layer pseudo-laminated structure, the above-mentioned effects can be obtained, the structural strength of the three-layer pseudo-laminated structure is improved, and the ability to retain body fluid is further improved. Further, since it has a three-layer pseudo-laminated structure, the highly absorbent polymer 12 is less likely to be unevenly distributed in one place in the SAP layer 17, and it is easy to maintain a state in which gel blocking is unlikely to occur by being dispersed almost uniformly throughout. ..

As the hot melt adhesive used for the first adhesive portion 14 and the second adhesive portion 15, those having a melting point of 100 ° C. or higher and 180 ° C. or lower can be used without particular limitation, and for example, a styrene-butadiene-styrene-based copolymer. Examples thereof include synthetic rubber-based hot-melt adhesives such as styrene-isoprene-styrene-based copolymers and olefin-based hot-melt adhesives such as ethylene-vinyl acetate copolymers. The first adhesive portion 14 and the second adhesive portion 15 use a hot melt adhesive, and a curtain coat method, a spiral method, or a contact method in which a hot melt adhesive in a molten state is applied from a nozzle in a non-contact manner, or a slot method is applied. It can be formed by using a known method such as.

<Second Embodiment of Absorber>
The absorber 20A is one of the modifications of the absorber 20, and the high-absorbent sheet 16 having a width longer than that of the high-absorbent sheet 16 used for manufacturing the absorber 20 is used, and the number of folds is 3 to 4. It has the same configuration as the absorber 20 except that the third sheet portion C rises diagonally from the crease with the second sheet portion B.

In the absorber 20A, when the bending angles between the first sheet portion A and the third sheet portion C and between the second sheet portion B and the third sheet portion C are appropriately selected, the inside of the absorber 20A can be selected. A space (FIG. 4) extending in the longitudinal direction is likely to be formed. This space has a slit-like function, promotes the diffusion of body fluid in the longitudinal direction of the absorber 20A, and becomes a temporary body fluid storage space to suppress the return of body fluid.

Even in the absorber 20A, the SAP fixation-supporting region of the first sheet portion A, the SAP fixation-supporting region of the second sheet portion B, and the SAP fixation-supporting region of the fourth sheet portion D partially overlap each other in the thickness direction. There is an overlapping area. At this time, the overlap ratio (X / Y) of the widthwise dimension X of the overlapping region with respect to the widthwise dimension Y of the second sheet portion B is in the range of 10% or more and 95% or less or 50%, as in the absorber 20. It is in the range of 95% or less. Further, the width direction dimension X of the overlapping region and the width direction dimension Y of the second sheet portion B are as described above.

The highly absorbent sheet 16 (FIGS. 3, 4, and 6) constituting the absorber 20 and the absorber 20A will be described in the order of the substrate nonwoven fabric 11, the highly absorbent polymer 12, and the hydrophilic sheet 13.

(Base non-woven fabric)
As shown in FIG. 5, a plurality of raised fibers 11x in which the fibers constituting the base nonwoven fabric 11 are raised are erected on one side surface 11a of the substrate nonwoven fabric 11. Therefore, in addition to the original bulkiness of the non-woven fabric, the highly absorbent sheet 16 is provided with an appropriate thickness and softness, a good cushioning property is generated, and a fit feeling when worn is improved. Further, when the substrate nonwoven fabric 11 is raised, the highly absorbent polymer 12 can be dispersed and fixedly supported between the raised fibers 11x. Examples of the method for raising the one-sided surface 11a of the substrate nonwoven fabric 11 include a method using a rotary saw blade, a needle punch, and the like, and a method using a rotary saw blade is preferable from the viewpoint of in-line productivity and cost.

The degree of raising of the substrate nonwoven fabric 11 is not particularly limited, and it is sufficient if the raising can be visually confirmed. For example, the raising rate as the degree of raising is in the range of 5% or more and 90% or less, or in the range of 8% or more and 80% or less. Is. The raising rate means the rate of increase in the thickness of the substrate nonwoven fabric 11 due to the raising process. When the thickness of the substrate nonwoven fabric 11 before raising is T1 and the thickness of the substrate nonwoven fabric 11 after raising is T2, the raising rate (%) = [(T2-T1) / T1] × 100. The thicknesses T1 and T2 are measured under no load using a height gauge (manufactured by Mitutoyo Co., Ltd.). Further, the fibers may be raised on the non-raised surface 11b of the substrate nonwoven fabric 11.

Examples of the base material constituting the substrate non-woven fabric 11 include non-woven fabrics such as air-through non-woven fabric, point-bonded non-woven fabric, spunbond non-woven fabric, and melt-blow non-woven fabric, spunbond non-woven fabric / melt-blow non-woven fabric laminate, spunbond non-woven fabric / melt-blow non-woven fabric / spunbond non-woven fabric. Examples thereof include composite non-woven fabrics such as laminates. Among these non-woven fabrics, air-through non-woven fabrics are preferable from the viewpoint of increasing the bulk.

The thickness of the substrate nonwoven fabric 11 is not particularly limited, but from the viewpoint of the balance between wearing feeling and absorption performance, a range of 0.3 mm or more and 11.0 mm or less, a range of 0.5 mm or more and 5.0 mm or less, or 0.5 mm or more 2 The range is 0.0 mm or less. The basis weight of the substrate nonwoven fabric 11 is not particularly limited, but is, for example, 20 g / m ² or more and 200 g / m ² or less, 20 g / m ² or more and 160 g / m ² or less, or 20 g / m ² or more and 80 g / g. The range is m ² or less.

When the air-through nonwoven fabric is used as the substrate nonwoven fabric 11, the basis weight of the air-through nonwoven fabric is in the range of 15 g / m ² or more and 80 g / m ² or less, and the thickness of the fibers constituting the air-through nonwoven fabric is in the range of 1.6 dtex or more and 14 dtex or less. The range is 1.8 dtex or more and 9.0 dtex or less, or 2.0 dtex or more and 6.0 dtex or less. By adjusting the thickness of the fibers constituting the air-through nonwoven fabric within the above range, the highly absorbent polymer 12 can be easily dispersed and supported between the raised fibers 11x of the air-through nonwoven fabric, and the highly absorbent polymer on the raised surface 11a can be easily fixed and supported. The uniform dispersibility of 12 is improved.

(Highly absorbent polymer)
The highly absorbent polymer 12 is not particularly limited as long as it can absorb urine and prevent backflow, and is a polyacrylic acid salt, a polyaspartate salt, a (starch / acrylic acid) graft copolymer, ( Examples thereof include a copolymer (acrylic acid / vinyl alcohol), a (isobutylene / maleic anhydride) copolymer, and a saponified product thereof. Among these, polyacrylic acid salt is preferable, and sodium polyacrylate is more preferable, from the viewpoint of the amount of absorption per weight. The basis weight of the highly absorbent polymer 12 in the SAP layer 17 of the highly absorbent sheet 16 is, for example, in the range of 100 g / m ² or more and 600 g / m ² or less.

By avoiding the use of the highly absorbent polymer 12 as a fine powder having poor fluidity as a powder, it is possible to improve the absorption performance such as the absorption rate and the absorption amount, and reduce the occurrence of a rugged tactile sensation. Therefore, the particulate high absorbency polymer 12 having a medium particle size is preferable. The medium particle size is, for example, in the range of 50 μm or more and 600 μm or less, or 100 μm or more and 500 μm or less.

In a preferred embodiment, the highly absorbent polymer 12 is anchored and supported between the raised fibers 11x by a hot melt adhesive. The hot melt adhesive reinforces the fixation support of the highly absorbent polymer 12 when the basis weight of the substrate nonwoven fabric 11 is relatively low or the like. The content of the hot melt adhesive is, for example, in the range of 10 g / m ² or less from the viewpoint of not impairing the absorbability of the highly absorbent polymer 12 and the touch when worn. As the hot melt adhesive, the same ones as those of the first adhesive layer 14 and the second adhesive layer 15 can be used, and the above-mentioned coating method can also be used as the coating method.

(Hydrophilic sheet)
The hydrophilic sheet 13 covering the SAP layer 17 of the substrate nonwoven fabric 11 diffuses the body fluid over the entire SAP layer 17, for example. The hydrophilic sheet 13 is fixed to the surface of the SAP layer 17 by hot melt adhesive, heat embossing, or the like. In a preferred embodiment, the hydrophilic sheet 13 has a bending stiffness of 0.015 gf · cm ² / cm or more and 0.080 gf from the viewpoint of achieving both the strength of the highly absorbent sheet 16 and the cushioning property and the softness in a well-balanced manner. -The range is cm ² / cm or less. If the bending stiffness is less than 0.015 gf · cm ² / cm, the hydrophilic sheet 13 tends to be too soft and the operability tends to deteriorate, and the absorber 20 also tends to be soft, so that leakage tends to occur easily when worn. There is. If the bending stiffness exceeds 0.080 gf · cm ² / cm, the absorber 20 tends to become hard and the softness and fit when worn tend to decrease. The method for measuring bending stiffness will be described later.

As the hydrophilic sheet 13, any of those commonly used in this field can be used, and examples thereof include tissue paper, absorbent paper, and hydrophilic non-woven fabric. Examples of the hydrophilic non-woven fabric include thermal-bonded non-woven fabric, spun-bonded non-woven fabric, air-laid non-woven fabric, air-through non-woven fabric, pulp-containing non-woven fabric and the like. Among these, tissue paper, hydrophilic non-woven fabric and the like are preferable from the viewpoint of availability and cost, and hydrophilic non-woven fabric such as thermal bond non-woven fabric, spunbond non-woven fabric, air-through non-woven fabric and pulp-containing non-woven fabric are more preferable, and air-through non-woven fabric and pulp. The contained non-woven fabric and the like are more preferable.

Here, the pulp-containing nonwoven fabric is a nonwoven fabric in which a spunbonded nonwoven fabric and a pulp fiber web are integrated on at least one surface of the spunbonded nonwoven fabric (for example, US Pat. No. 5,284,703). The pulp-containing nonwoven fabric is produced, for example, by striking pulp fibers against a spunbonded nonwoven fabric under a high-pressure water stream by a water flow confounding method. In the pulp-containing nonwoven fabric obtained by this method, the fibers of the spunbonded nonwoven fabric and the valve pulp fibers of the pulp fiber web are entangled, and a part of the pulp fibers penetrates the spunbonded nonwoven fabric in the thickness direction. It is a tightly integrated non-woven fabric and pulp fiber web.

The basis weight of the hydrophilic sheet 13 is, for example, in the range of 15 g / m ² or more and 80 g / m ² or less. In the three-layer laminated body of the present embodiment, the hydrophilic sheets 13 having a plurality of layers are laminated in the thickness direction, but when the basis weight of the hydrophilic sheets 13 is selected from the above range, the absorber 20 and the absorber 20A are selected. The overall fluid diffusivity is maintained at a high level. Further, when the basis weight of the hydrophilic sheet 13 is within the above-mentioned range, the thickness thereof can be reduced, and the absorber 20 and the absorber 20A are prevented from becoming unnecessarily bulky. As a result, a good wearing feeling of the absorbent article 50 is maintained.

(Dimensions and shape of absorber)
The absorbers 20 and 20A have a length of, for example, 100 mm or more and 800 mm or less, a range of 150 mm or more and 500 mm or less, or a range of 270 mm or more and 500 mm or less, and a width of, for example, 50 mm or more and 500 mm or less, 60 mm or more and 400 mm or less. It is a range, or a range of 90 mm or more and 190 mm or less. When the plan view shape of the absorbers 20 and 20A is an hourglass shape, the length is in the range of 180 mm or more and 480 mm or less, and the widths of the ventral and dorsal parts that come into contact with the wearer's abdomen and back are both. The range is 60 mm or more and 160 mm or less, and the width of the crotch portion that abuts on the lower crotch of the wearer is 50 mm or more and 140 mm or less. Further, the entire surface or a part of the absorbers 20 and 20A may be embossed. Examples of the plan view shape of the absorbers 20 and 20A include an hourglass shape, an I-shape, a rectangle, a rounded quadrangle with rounded four corners, an oval, and the like.

Further, in order to prevent leakage of SAP particles and further stabilize the shape of the absorbers 20 and 20A, the absorbers 20 and 20A may be wrapped with a carrier sheet. The base material of the carrier sheet may be any one having hydrophilicity, and examples thereof include hydrophilic non-woven fabrics such as tissue paper, absorbent paper, and air-laid non-woven fabric. When a plurality of carrier sheets are provided, the base materials of the plurality of carrier sheets may be the same or different.

<Manufacturing method of absorber>
The method for producing the absorber 20 and the absorber 20A is not particularly limited, and examples thereof include the following methods. The surface of one side of the substrate nonwoven fabric 11 is raised using a rotary saw blade or a needle punch. Then, the highly absorbent polymer 12 is fixedly supported between the raised fibers 11x on the raised surface 11a of the substrate nonwoven fabric 11 with a hot melt adhesive or the like to form an SAP layer. After that, the SAP layer 17 of the substrate nonwoven fabric 11 and the hydrophilic sheet 13 are adhered with a hot melt adhesive or the like to prepare a highly absorbent sheet 16. When the highly absorbent sheet 16 is bent at a predetermined bending angle at a predetermined intermediate portion in the width direction, the absorber 20 and the absorber 20A can be obtained. In the absorber 20 and the absorber 20A, the folds of each bent portion are configured to draw a smooth arc, but they may be configured to be angular.

<Back sheet>
For the back sheet 30, a base material having a liquid impermeable property is used so that the body fluid held by the absorber 20 does not wet the clothes. Examples of the base material include a resin film, a composite sheet which is a laminate of a resin film and a non-woven fabric, and the like. The non-woven fabric used for the composite sheet is not particularly limited in the manufacturing method, and for example, spunbond non-woven fabric, melt-blow non-woven fabric, composite non-woven fabric which is a laminate of spunbond non-woven fabric / melt-blow non-woven fabric, spunbond non-woven fabric / melt-blow non-woven fabric / spunbond non-woven fabric. Examples thereof include a composite non-woven fabric which is a laminated body, and a composite material which is a laminated body of two or more of these. Examples of the resin film include films such as polyester, polyvinyl alcohol, polyethylene and polypropylene, and composite films of polyethylene and polypropylene.

The basis weight of the back sheet 30 is in the range of 15 g / m ² or more and 40 g / m ² or less, for example, from the viewpoint of strength and workability. Further, from the viewpoint of preventing stuffiness during wearing, the back sheet 30 having breathability is preferable. In order to impart air permeability to the back sheet 30, for example, a method of blending a filler in the resin film, a method of embossing the back sheet 30 for perforation, and the like can be used. Here, examples of the filler include calcium carbonate, and the filler can be blended according to a known method.

<Three-dimensional gather>
The three-dimensional gathers 40 are provided along the longitudinal direction near both ends of the skin side surface of the top sheet 10, for example, in order to prevent lateral leakage of the body fluid excreted by the user. In the three-dimensional gather 40 of the present embodiment, one end in the width direction is fixed near both ends of the skin side surface of the back sheet 30, the middle portion in the width direction is fixed near both ends of the skin side surface of the top sheet 10, and the other end in the width direction is the top. It is a free end 40a that is not fixed to the sheet 10. An elastic stretchable member (not shown) is arranged in the vicinity of the free end 40a along the longitudinal direction to give the free end 40a uprightness so that it can be deformed according to the wearer's body shape.

The fixed position of one end in the width direction of the three-dimensional gather 40 is not limited to the present embodiment, and for example, the vicinity of both ends in the width direction of the non-skin side surface of the back sheet 30, and each edge of the top sheet 10 and the back sheet 30 is partially or Examples thereof include the vicinity of both ends in the width direction of the bag body which is entirely joined and houses the absorber 20 inside, and the vicinity of both ends in the width direction of the skin side surface of the top sheet 10. The absorbent article 50 also includes an embodiment that does not include the three-dimensional gather 40.

As the sheet base material constituting the three-dimensional gather 40, a water-repellent and / or liquid-impermeable nonwoven fabric formed of hydrophobic fibers can be used without particular limitation, and for example, a spunbonded nonwoven fabric, a melt blow nonwoven fabric, and a spunbonded nonwoven fabric can be used. / Melt blow non-woven fabric / Composite non-woven fabric which is a laminate of spunbond non-woven fabric and the like can be mentioned. As the elastic elastic member, regular items in this field can be used without particular limitation, and examples thereof include polyurethane yarn, strip-shaped polyurethane film, thread-shaped or strip-shaped natural rubber, and the like. The basis weight of the nonwoven fabric constituting the three-dimensional gather 40 is, for example, in the range of 13 g / m ² or more and 20 g / m ² or less.

<Transfer sheet>
The absorbent article 50 may include a transfer sheet (not shown). The transfer is placed, for example, between the topsheet 10 and the absorber 20 (or absorber 20A). The transfer sheet is not particularly limited as long as it is a liquid-permeable substrate, and is, for example, the same type or different types of non-woven fabrics such as air-through non-woven fabrics, thermal bonded non-woven fabrics, and spunbonded non-woven fabrics, and thermal-bonded non-woven fabrics / spunbonded non-woven fabric laminates. Examples thereof include a composite non-woven fabric in which non-woven fabrics are laminated, a foamed film made of urethane foam, polyethylene foam and the like, and a composite sheet which is a laminate of two or more of these. Among these, an air-through non-woven fabric is preferable from the viewpoint of preventing the transfer of body fluid to the three-dimensional gather 40. The basis weight of the transfer sheet is, for example, in the range of 20 g / m ² or more or in the range of 20 g / m ² or more and 60 g / m ² or less.

<Manufacturing method of absorbent articles>
The absorbent article 50 can be manufactured by a known manufacturing method. For example, a step of arranging the absorbent body 20 or the absorbent body 20A between the top sheet 10 and the back sheet 30, and the top sheet 10 and the back sheet 30 are provided. A step of fixing using hot melt adhesive, heat embossing, ultrasonic embossing, high frequency embossing, etc. over a part or the whole circumference, and a step of installing a three-dimensional gather 40 at a predetermined position of the back sheet 30 and the top sheet 10. , A manufacturing method including. When the absorbent article 50 is a urine absorbing pad or a light incontinence pad, it may be individually wrapped in a package and then folded in three in the longitudinal direction. Further, leg gathers, waist gathers, side flaps and the like are appropriately provided depending on the use and form of the absorbent article 50.

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

Examples and comparative examples will be given below, and an example of this embodiment will be described more specifically.

(Examples 1 to 4, Comparative Examples 1 and 2)
First, an air-through nonwoven fabric having each of the physical characteristics and dimensions shown in Table 1 is prepared as the substrate nonwoven fabric, and one side surface of the substrate nonwoven fabric is physically brushed with a rotary saw blade to disperse a highly absorbent polymer (basis weight 240 g). / M ² ) and hot melt adhesive (10 g / m ² ) were used to fix and support the raised portions of the substrate non-woven fabric between the fibers. Further, an air-through nonwoven fabric having each physical property and size shown in Table 1 as a hydrophilic sheet (bending stiffness gf · cm ² / cm, Example 1: 0.019, Example 2: 0.031, Comparative Example 1: 0). 1.012, Comparative Example 2: 0.085) was prepared, and the raised surface side of the substrate nonwoven fabric was adhered to a hydrophilic sheet coated with a hot melt adhesive to obtain a highly absorbent sheet. Next, the highly absorbent sheet is bent into the three-layer pseudo-laminated structure shown in FIG. 3 so that the non-raised surface of the substrate nonwoven fabric faces inward, and each sheet portion is hot-melt bonded near both ends in the width direction of the highly absorbent sheet. It was fixed with an agent. In this way, the absorbers of Examples 1 to 4 and Comparative Examples 1 and 2 were prepared.

Next, an air-through non-woven fabric (basis weight 25 g / m 2) was used as the top sheet, and an air-through non-woven fabric (basis weight 30 g / m ² ) was used as the transfer sheet, and the absorbers of Examples 1 to 4 and Comparative Examples 1 and ² were used. The first sheet is used so that it is located on the top sheet side, a breathable polyethylene sheet (basis weight 30 g / m ² ) is used as a liquid-impermeable back sheet, and spunbond non-woven fabric / meltblown non-woven fabric / spunbond is used as a three-dimensional gather. Absorbent articles of Examples 1 to 4 and Comparative Examples 1 and 2 were prepared using a composite non-woven fabric (basis weight 15 g / m ² ) which is a laminated body of non-woven fabric.

(Comparative Example 3)
An air-through nonwoven fabric having each of the physical characteristics and dimensions shown in Table 1 is prepared as the substrate nonwoven fabric, and one side surface of the substrate nonwoven fabric is physically brushed with a rotary saw blade to disperse a highly absorbent polymer (basis weight 360 g / m). ² ) It was fixedly supported between the fibers of the raised portion of the substrate non-woven fabric with a hot melt adhesive. Further, as a hydrophilic sheet, an air-through nonwoven fabric having each of the physical characteristics and dimensions shown in Table 1 is prepared, and the raised surface side of the substrate nonwoven fabric and the hydrophilic sheet coated with a hot melt adhesive are adhered to each other to form a highly absorbent sheet. Got Next, a highly absorbent sheet is placed so that the raised surface of the substrate non-woven fabric faces outward, leaving a central portion of 60 mm, C-folding the left and right sides toward the center, and hot-melt bonding the hydrophilic sheets that overlap at the central portion. The absorbent article of Comparative Example 3 was prepared in the same manner as in Example 1 except that the absorbent was fixed with an agent and the SAP layers did not overlap in the thickness direction.

(Comparative Example 4)
Highly absorbent sheet (dimensions in the width direction) obtained by laminating air-through non-woven fabric (basis weight 20 g / m ² ) / high-absorbent polymer (basis weight 240 g / m ² ) / air-through non-woven fabric (basis weight 20 g / m ² ). An absorbent article was produced in the same manner as in Example 1 except that three layers (all 60 mm) were stacked and used as an absorber. The air-through nonwoven fabric used in Comparative Example 4 was not brushed like the substrate nonwoven fabric used in Example 1.

[Measurement item]
The absorption rates were measured using the absorbent articles obtained in Examples 1 to 4 and Comparative Examples 1 to 4, and the results are shown in Table 1.
(Absorption rate)
40 ml of 0.9 mass% physiological saline (37 ° C.) was poured from a cylinder having an inner diameter of 30 mm into each of the absorbent articles of Examples 1 to 4 and Comparative Examples 1 to 4 under a pressure of 46 g / cm2, and the physiology was performed. The time (seconds) until the saline solution is absorbed on the surface of the absorber is measured as the first absorption rate. After 3 minutes have passed, 40 ml of 0.9% by mass physiological saline (37 ° C.) is injected again, and the time (seconds) until the physiological saline is absorbed on the surface of the absorber is measured as the second absorption rate. The smaller the value, the better the absorbency.

Further, each of the absorbent articles of Examples 1 to 4 and Comparative Examples 1 to 4 was subjected to operability evaluation and sensory evaluation, and evaluated according to the following evaluation criteria. The results are shown in Table 1.
(Operability)
〇: Normal production was possible without slowing down the operation.
Δ: The speed of operation was 1% or more and 10% or less lower than usual.
X: The operating speed decreased by more than 10% as compared with the normal case.
(sensory evaluation)
Eight panelists were asked to wear each of the absorbent articles of Examples 1 to 4 and Comparative Examples 1 to 4, and the wearing feeling (fitness, softness) and absorbency (presence or absence of leakage to the outside of the absorbent articles). Was evaluated by sensory evaluation with two choices, "good" or "bad". The wearer used it for 8 hours and evaluated it in daily activities, and the results are shown in Table 1.
〇: When the number of wearers who chose "good" is 6 or more and 8 or less △: When the number of wearers who chose "good" is 3 or more and 5 or less ×: 1 wearer who chose "good" When there are one or two people, or when there is no wearer who chose "good"

The bending stiffness (flexural rigidity) of each sheet was measured by the following method.
(Bending stiffness)
Bending stiffness (flexural rigidity) was measured by inserting a sample (100 mm × 100 mm) into a fixed chuck and a moving chuck of a bending tester (trade name: KES-FB2, manufactured by Kato Tech Co., Ltd.). The moving chuck moves to the maximum positive curvature + 2.5 cm ^-1 and reverses to pass the curvature 0, then moves to the negative maximum curvature -2.5 cm ^-1 and reverses to complete the measurement with a curvature of 0. In this way, a reciprocating curve of the bending moment with respect to the curvature of one cycle is obtained. In the reciprocating curve of the bending moment, the average value of the slope between the curvatures 0.5 cm ^-1 and 1.5 cm ^-1 and the slope between the curvatures -0.5 cm ^-1 and -1.5 cm ^-1 was taken as the bending stiffness. ..

From Table 1, according to the present embodiment, an absorbent article having excellent softness and fit, good wearing feeling, and high productivity while maintaining a high level of absorption performance such as absorption rate and absorption amount. Can be found to be obtained.

10 Top sheet 11 Base non-woven fabric 11a Brushed surface 11b Non-raised surface 11x Brushed fiber 12 Highly absorbent polymer 13 Hydrophilic sheet 14 First adhesive layer 15 Second adhesive layer 16 Highly absorbent sheet 17 SAP layer (SAP fixed support layer) )
20, 20A Absorber 30 Back sheet 40 Three-dimensional gather 40a Free end 50 Absorbable article A 1st sheet part B 2nd sheet part C 3rd sheet part D 4th sheet part

Claims (7)

An absorbent article comprising a liquid permeable top sheet, a liquid permeable back sheet, and an absorber disposed between them.
The absorber is
A base non-woven fabric having a raised surface on which a plurality of raised fibers are erected and a non-raised surface,
A highly absorbent polymer fixedly supported between the raised fibers on the raised surface of the substrate nonwoven fabric, and
It has a highly absorbent sheet comprising a hydrophilic sheet covering the raised surface on which the highly absorbent polymer of the substrate nonwoven fabric is fixedly supported.
The highly absorbent sheet is
It has a laminated structure including four first to fourth sheet portions bent along the longitudinal direction in the middle of the width direction and with the non-raised surface of the substrate nonwoven fabric inward.
The first sheet portion is located closest to the skin of the wearer, and one end in the width direction is one end in the width direction of the highly absorbent sheet.
The second seat portion is located on the most non-skin side of the wearer and faces the first seat portion in the thickness direction, and one end and the other end in the width direction are the fourth seat portion and the third seat portion, respectively. Connected to
The third sheet portion rises from the other end in the width direction of the second sheet portion in the thickness direction and is connected to the other end in the width direction of the first sheet portion.
The fourth sheet portion is located between the first sheet portion and the second sheet portion in the thickness direction, and the other end in the width direction is the other end in the width direction of the highly absorbent sheet.
The fixation-supporting region of the highly absorbent polymer in the first sheet portion, the fixation-supporting region of the highly-absorbent polymer in the second sheet portion, and the fixation of the highly-absorbent polymer in the fourth sheet portion. The overlapping region where the supported region overlaps in the thickness direction and the overlapping region,
A first adhesive portion for fixing the first sheet portion and the fourth sheet portion in the vicinity of one end in the width direction of the highly absorbent sheet, and
An absorbent article further comprising a second adhesive portion for fixing the second sheet portion and the fourth sheet portion in the vicinity of the other end in the width direction of the highly absorbent sheet. The absorbent article according to claim 1, wherein the widthwise dimension of the overlapping region is 10% or more and 95% or less of the widthwise dimension of the second sheet. The absorbent article according to claim 1 or 2, wherein the hydrophilic sheet has a basis weight of 15 g / m ² or more and 80 g / m ² or less. The absorbent article according to any one of claims 1 to 3, wherein the hydrophilic sheet has a bending stiffness of 0.015 gf · cm ² / cm or more and 0.080 gf · cm ² / cm or less. The absorbent article according to any one of claims 1 to 4, wherein the substrate nonwoven fabric has a basis weight of 20 g / m ² or more and 80 g / m ² or less. The absorbent article according to any one of claims 1 to 5, wherein the substrate nonwoven fabric is an air-through nonwoven fabric, and the thickness of the fibers constituting the air-through nonwoven fabric is 1.6 dtex or more and 14 dtex or less. The absorbent article according to any one of claims 1 to 6, wherein the highly absorbent polymer has a basis weight of 100 g / m ² or more and 600 g / m ² or less in the highly absorbent sheet.

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