JP2021119887A - Absorbent article - Google Patents

Abstract

To provide an absorbent article which has good wear feeling and fitting feeling and excellent diffusibility of body fluid and absorption rate.SOLUTION: An absorbent article 50 includes a liquid permeable top sheet 25, a liquid impermeable back sheet 30, and an absorber 1 between them. The absorber 1 is provided with: a high absorbent sheet 10 which includes a base body nonwoven fabric 11 having a napping surface 11a and a non-napping sheet 11b facing the top sheet 25 and a high absorbent polymer 12 fixed and supported between napped fibers 11x of the napping surface 11a of base body nonwoven fabric 11; and a hydrophilic sheet 20 covering the napping surface 11a of the base body nonwoven fabric 11. The hydrophilic sheet 20 includes first air-through nonwoven fabric whose flexural rigidity ranges from 0.02 to 0.6 gf.cm2/cm.SELECTED DRAWING: Figure 4

Description

The present invention relates to absorbent articles.

The absorbable article generally includes 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. 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, it is common to use fluff pulp and a super absorbent polymer (hereinafter, also referred to as “SAP”) in combination. 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, the two non-woven fabrics were fixed with a hot melt adhesive between them. Various absorbent articles using SAP particles and a highly absorbent sheet containing (hereinafter, also referred to as "SAP sheet") as an absorber have been proposed.

For example, in Patent Document 1, one surface is arranged in a stripe shape extending in the longitudinal direction between the first and second nonwoven fabrics, each of which is an adhesive-coated surface, and the adhesive-coated surfaces of the first and second nonwoven fabrics. The adhesive is intermittently applied in the area facing the SAP layer on the adhesive-coated surface of the second non-woven fabric, and the adhesive is intermittently applied on both sides of the SAP layer in the width direction without interposing the SAP layer. A highly absorbent sheet in which an adhesive is continuously applied in the longitudinal direction is disclosed on each of the adhesive-coated surfaces of the first and second nonwoven fabrics that are directly opposed to each other.

In Patent Document 2, the absorber disposed between the top sheet and the back sheet includes first and second absorbers containing two non-woven fabrics and SAP particles arranged between them, respectively. The first and second absorbers arranged on one and the other in the width direction have first and second folds extending in the longitudinal direction, respectively, and the first and second folds face each other to form a highly absorbent sheet. It is disclosed. Further, Patent Document 2 further includes a third absorber containing two non-woven fabrics and SAP particles arranged between them, and the third absorber is arranged above the first and second absorbers. Sexual articles are disclosed.

Japanese Unexamined Patent Publication No. 2006-158676 Japanese Unexamined Patent Publication No. 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 can feel 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 fitting is 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 diffusivity of body fluid, absorption rate, and absorption.

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 of body fluid and absorption rate.

As a result of intensive research to solve the above problems, the present inventor is a high-absorptive sheet in which a high-absorbent polymer is fixed between non-woven fabrics with a hot melt adhesive, which is a conventional high-absorbent sheet. We have succeeded in obtaining an absorbent article having a desired highly absorbent sheet that can solve the problem, and have completed the present invention. The present invention provides, as a preferred embodiment, the absorbent articles (1) to (5) below.

(1) An absorbent article comprising a liquid-permeable top sheet, a liquid-impermeable back sheet, and an absorber arranged between the top sheet and the back sheet.
The absorber has a raised surface and a non-raised surface, and is fixedly supported between a base non-woven fabric in which the non-raised surface is arranged so as to face the top sheet and the raised fibers of the raised surface of the base non-woven fabric. A highly absorbent sheet containing the highly absorbent polymer and a hydrophilic sheet covering the raised surface of the substrate nonwoven fabric are provided, and the hydrophilic sheet has a bending stiffness of 0.02 gf · cm ² / cm or more 0. An absorbent article comprising a first air-through non-woven fabric of .6 gf · cm ^{2 / cm or less.}
(2) The hydrophilic sheet has both end faces in the width direction facing each other between the top sheet and the base non-woven fabric, and covers both end faces in the width direction of the base non-woven fabric together with the raised surface of the base non-woven fabric. The absorbent article according to claim 1, which has a three-dimensional shape folded in three.
(3) The hydrophilic sheet is stretched in the width direction so that both ends in the width direction cover the non-raised surface of the substrate nonwoven fabric and overlap each other, and the overlapping width dimension is 5 of the width dimension of the absorber. % Or more and 50% or less, the absorbent article of the above (1) or (2).
(4) The first air-through non-woven fabric is an absorbent article according to any one of (1) to (3) above, which ^{has a basis weight of 20 g / m 2} or more and 100 g / m ^{2 or less.}
(5) The substrate non-woven fabric is the second air-through non-woven fabric, the basis weight of the second air-through non-woven fabric is 20 g / m ² or more and 80 g / m ² or less, and the thickness of the fibers constituting the second air-through non-woven fabric is large. The absorbent article according to any one of (1) to (4) above, which has a size of 1.6 dtex or more and 14 dtex or less.
(6) The absorbent article according to any one of (1) to (5) above, wherein the basis weight of the highly absorbent polymer in the highly absorbent sheet is 200 g / m ² or more and 1200 g / m ^{2 or less.}

According to the present invention, it is possible to provide 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 top view which shows typically the structure of the absorbent article which concerns on 1st Embodiment of this invention. It is a perspective view which shows typically the structure of the substrate nonwoven fabric provided in the absorbent article shown in FIG. It is a side view which shows typically the structure of the highly absorbent sheet provided in the absorbent article shown in FIG. It is sectional drawing which shows typically the structure of the absorber provided in the absorbent article shown in FIG. It is sectional drawing which shows typically the structure of the absorber which concerns on another embodiment.

Hereinafter, the absorbent article 50 of the present embodiment will be described in more detail with reference to the drawings. FIG. 1 is a schematic plan view of the absorbent article 50 from the top sheet 25 side. FIG. 2 is a schematic perspective view of the substrate nonwoven fabric 11. FIG. 3 is a schematic side view of the high absorption sheet 10. 4 to 5 are schematic cross-sectional views of the absorbers 1 and 2, respectively. In each figure, the constituent members are described so as to be in close contact with each other, but at least one of the constituent members may have one or a plurality of gaps. Further, each figure does not define the magnitude relationship of the dimensions of each component of the absorbent article 50.

The longitudinal direction of the absorbent article 50 is the direction indicated by Y in the drawing, which extends to the front and back of the body through the crotch portion of the wearer when the absorbent article 50 is worn. The width direction of the absorbent article 50 is the direction indicated by X in the drawing, which is orthogonal to the longitudinal direction. The thickness direction of the absorbent article 50 is the direction indicated by Z in the drawing in which the constituent members such as the top sheet 25, the absorber 1, and the back sheet 30 are laminated. The skin side surface of the absorbent article 50 and each component contained therein is a surface in contact with the wearer's skin and a surface facing the skin, and a non-skin side surface is a surface in contact with the wearer's clothing or facing the clothing. It is the surface. Body fluid refers to the liquid excreted from the body such as urine, blood, and water in loose stool.

<Absorbable article>
The absorbent article 50 of the present embodiment can be used as various absorbent articles regardless of whether it is for babies or adults, but typically, a light incontinence pad, a urine absorbing pad, a pants-type disposable diaper, a tape-stopping disposable diaper, etc. Can be mentioned. Various paper diapers as an outer and an absorbent article 50 as an inner may be combined. The dimensions of the absorbent article 50 in the longitudinal direction and the width direction are not particularly limited, but are, for example, 100 mm or more and 800 mm or less, and 50 mm or more and 500 mm or less, respectively. By adjusting the dimensions of the absorbent article 50 to the above range, absorbent articles of various uses can be obtained.

As shown in FIG. 1, the absorbent article 50 of the present embodiment is arranged so as to face the liquid-permeable top sheet 25 and the top sheet 25, which are located relatively on the skin side when worn. The liquid-impermeable back sheet 30 located on the non-skin side when worn, the absorber 1 arranged between the top sheet 25 and the back sheet 30, and the skin of the top sheet 25. It includes a pair of three-dimensional gathers 40 provided on the side surface. The absorber 1 has a structure sandwiched between the top sheet 25 and the back sheet 30, and body fluid such as urine is absorbed and held by the absorber 1 through the top sheet 25. Leg gathers, waist gathers, side flaps and the like can be appropriately provided depending on the use and type of the absorbent article 50. In the absorbent article 50 of the present embodiment, the absorbers 1 and 2 do not contain fluff pulp, the return of body fluids such as urine is suppressed, a smooth and comfortable touch is maintained, and the absorbability of body fluids and wearing are performed. It also includes a form that has a good feeling and fit and does not cause discomfort while being worn.

Hereinafter, each of the sheet-shaped or plate-shaped constituent members will be described in more detail in the order of the top sheet 25, the absorber 1, the back sheet 30, and the three-dimensional gather 40. In addition, these constituent members may have a three-dimensional structure other than a sheet shape and a plate shape.

(Top sheet)
The top sheet 25 is a liquid-permeable sheet-like member that allows body fluids to quickly pass toward the absorber 1, and is arranged so as to face the back sheet 30 with the absorber 1 interposed therebetween. Since the top sheet 25 may come into contact with the wearer's skin, a base material having a soft feel and not irritating to the skin is preferable. Examples of the base material include a hydrophilic non-woven fabric, a composite non-woven fabric which is a product of the same or different types of hydrophilic non-woven fabric, an open film such as an open polyethylene film, and a foam film such as urethane foam. The hydrophilic non-woven fabric uses, for example, synthetic fibers made of synthetic resin such as polypropylene or polyethylene, recycled fibers such as rayon, and natural fibers such as cotton, and is subjected to an air-through method, a thermal bond method, a spunlace method, a spunbond method, etc. It is obtained by processing by a known method.

Further, the surface of the top sheet 25 may be embossed or perforated in order to improve the liquid permeability. As a method for performing these embossing and drilling processes, known methods can be carried out without limitation. Further, in order to reduce irritation to the skin, the top sheet 25 may contain a lotion, an antioxidant, an anti-inflammatory component, a pH adjuster, an antibacterial agent, a moisturizer and the like.

From the viewpoint of strength, workability and liquid return amount, the basis weight of the top sheet 25 ^{is preferably 15 g / m 2} or more and 40 g / m ² or less. The shape of the top sheet 25 is not particularly limited, and may be any shape that covers the absorber 1 that is required to guide the body fluid to the absorber 1 so as not to leak.

(Absorber)
As shown in FIGS. 2 to 4, the absorber 1 of the present embodiment includes a highly absorbent sheet 10 and a hydrophilic sheet 20. The highly absorbent sheet 10 includes a substrate nonwoven fabric 11 having a raised surface 11a and a non-raised surface 11b, and a highly absorbent polymer 12 fixedly supported between the raised fibers 11x of the raised surface 11a of the substrate nonwoven fabric 11. In the highly absorbent sheet 10, the substrate nonwoven fabric 11 is arranged so that the non-raised surface 11b faces the top sheet 25. The hydrophilic sheet 20 includes a first air-through ^{nonwoven fabric having a bending stiffness of 0.02 gf · cm 2} / cm or more and 0.6 gf · cm ² / cm or less, and the raised surface 11a of the substrate nonwoven fabric 11 in the highly absorbent sheet 10 includes. Cover. Further, the hydrophilic sheet 20 has a flat sheet-like three-dimensional shape that covers the raised surface 11a of the substrate nonwoven fabric 11, and preferably covers both end surfaces 11A and 11B in the width direction together with the raised surface 11a of the substrate nonwoven fabric 11. , It has a three-dimensional shape folded in three, and more preferably, both end surfaces 20a and 20b in the width direction face each other between the top sheet 25 and the base non-woven fabric 11, and together with the raised surface 11a of the base non-woven fabric 11, the width direction thereof. It has a three-dimensional shape that is folded in three so as to cover both end faces 11A and 11B.

The size of the absorber 1 of the present embodiment in the longitudinal direction is preferably 100 mm or more and 800 mm or less, and more preferably 150 mm or more and 500 mm or less. Further, the dimension D in the width direction of the absorber 1 is preferably 50 mm or more and 500 mm or less, and more preferably 60 mm or more and 400 mm or less.

In the present embodiment, as described above, the hydrophilic sheet 20 covers the raised surface 11a of the base non-woven fabric 11, preferably the raised surface 11a of the base non-woven fabric 11, and the widthwise both end surfaces 11A and 11B of the base non-woven fabric 11. More preferably, it covers the raised surfaces 11a of the base non-woven fabric 11, the widthwise both end surfaces 11A and 11B of the base non-woven fabric 11, and the widthwise both ends of the non-woven surface 11b of the base non-woven fabric 11 and the peripheral region extending in the longitudinal direction, and is hydrophilic. The absorber 1 maintains its thinness by using the first air-through non-woven fabric having a bending stiffness (flexural rigidity) of 0.02 gf · cm ² / cm or more and 0.6 gf · cm ^{2 / cm or less as the property sheet 20.} However, it is not too soft, has moderate rigidity, improves wearing feeling and fit, and this improvement is reflected in the entire absorbent article 50, and when mass-producing the absorber 1 and the absorbent article 50. Since the absorber 1 is not too soft and has appropriate rigidity, the operability is stable, the operating speed is not lowered, and the defective product rate is greatly lowered. That is, the present inventors have determined that the bending stiffness (flexural rigidity) of the hydrophilic sheet 20 covering the raised surface 11a side of the base non-woven fabric 11 of the highly absorbent sheet 10 is the rigidity of the absorber 1 as a whole and the absorber 1 and the like. We have found that it has a great effect on the operational stability (operation speed, breakage and process defects) of the absorbent article 50 during mass production, and by setting the flexural rigidity within a predetermined range, the flexibility is not impaired. It has been found that the rigidity, the decrease in breakage, and the prevention of process defects can be satisfied at a high level. If the bending stiffness is ^{less than 0.02 gf · cm 2} / cm, the rigidity of the absorber 1 tends to be excessively lowered, and the breakage and the process speed tend to be lowered, and the occurrence of process defects tends to increase. If it exceeds 6 gf · cm ² / cm, the absorber 1 becomes too hard, the wearability and fit of the absorbent article 50 tend to decrease, and the discomfort when worn tends to increase.

Further, according to the present embodiment, when the high-absorbent polymer 12 is fixedly supported between the raised fibers 11x of the raised surface 11a of the base nonwoven fabric 11 in the high-absorbent sheet 10, the high-absorbent polymer 12 is raised with the raised surface 11a. Since it is supported by the fibers 11x, the amount of the hot melt adhesive used can be reduced, the densification of the highly absorbent polymer 12 is suppressed, and the polymer 12 causes the body fluid to surround the highly absorbent polymer 12. It can absorb and form an expandable space. As a result, the diffusivity of the body fluid as a whole of the absorber 1 and the absorption rate of the body fluid are increased, and the stiff feeling derived from the hot melt adhesive is less likely to occur. Further, since the raised surface 11a of the substrate nonwoven fabric 11 which is a constituent member of the absorber 1 is covered with the first air-through nonwoven fabric as the hydrophilic sheet 20, the body fluid is uniformly distributed throughout the absorber 1 and the absorber 1 is used. 1 The whole body fluid can be efficiently absorbed. Therefore, the absorbent article 50 including the absorbent body 1 has high diffusivity and nostalgic speed of body fluid, is excellent in body fluid absorbency, and has a good wearing feeling.

Further, according to the present embodiment, the absorber 1 is configured such that the non-raised surface 11b of the substrate nonwoven fabric 11 faces the top sheet 25. In particular, as in the absorber 2 shown in FIG. 5, the non-raised surfaces 11b of the substrate non-woven fabric 11 are configured so that the both end surfaces 20a and 20b in the width direction of the hydrophilic sheet 20 are stretched and overlapped to be closed. The diffusivity and absorption rate of body fluids are further significantly improved.

Hereinafter, the absorber 1 and each component thereof will be described.

(Base non-woven fabric)
As shown in FIG. 2, the one-sided surface 11a of the base non-woven fabric 11 is in a state in which the fibers 11x constituting the base non-woven fabric 11 are raised. Therefore, in addition to the original bulkiness of the non-woven fabric, by imparting an appropriate thickness and softness to the highly absorbent sheet 10, an appropriate cushioning property can be generated and a fit feeling at the time of wearing can be improved. Further, by raising the base nonwoven fabric 11 as described above, the highly absorbent polymer 12 can be dispersed and fixedly supported between the raised fibers 11x of the substrate nonwoven fabric 11. Examples of the method for raising the one-sided surface 11a of the substrate nonwoven fabric 11 include a rotary saw blade and a needle punch, and it is preferable to use a method of raising the fluff with the rotary saw blade from the viewpoint of in-line productivity and cost.

The raised state in the present embodiment is not particularly limited, and it is sufficient if the raised state can be visually confirmed. More specifically, the raised rate of the substrate nonwoven fabric 11 is preferably 5% or more and 90% or less, and 8% or more and 80%. More preferably, it is less than%. The brushing rate means the rate of increase in the thickness of the substrate nonwoven fabric 11 due to the brushing process. For example, when the thickness of the base non-woven fabric 11 before raising is T1 and the thickness of the base non-woven fabric 11 after raising is T2, the raising rate (%) is represented by [(T2-T1) / T1] × 100. Can be done. The above thickness is obtained by measuring the thickness under no load using a height gauge (manufactured by Mitutoyo Co., Ltd.). The other surface 11b of the substrate nonwoven fabric 11 is a non-raised surface in the present embodiment, but the present invention is not limited to this, and fibers may be raised.

Examples of 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, and composite non-woven fabric in which spunbond non-woven fabric / melt-blow non-woven fabric, spunbond non-woven fabric / melt-blow non-woven fabric / spunbond non-woven fabric are laminated. be able to. Of these non-woven fabrics, it is preferable to use an air-through non-woven fabric (second air-through non-woven fabric) whose bulkiness is easily obtained.

The thickness of the substrate nonwoven fabric 11 is preferably 0.3 mm or more and 11.0 mm or less, more preferably 0.5 mm or more and 5.0 mm or less, from the viewpoint of the balance between wearing feeling and absorption performance. It is more preferably 5 mm or more and 2.0 mm or less. The basis weight of the base nonwoven 11 is preferably 20 g / ^{m 2} or more 200 g / ^{m 2} or less, more preferably 20 g / ^{m 2} or more 160 g / ^{m 2} or less, 20 g / ^{m 2} or more 80 g / It is more preferably m ^{2 or less.}

When the second air-through nonwoven fabric is used as the substrate nonwoven fabric 11, the basis weight of the second air-through nonwoven fabric is 20 g / m ² or more and 80 g / m ² or less, and the thickness of the fibers constituting the second air-through nonwoven fabric is preferable. Is 1.6 dtex or more and 14 dtex or less, more preferably 1.8 dtex or more and 9.0 dtex or less, and further preferably 2.0 dtex or more and 6.0 dtex or less. By adjusting the thickness of the fibers constituting the second air-through non-woven fabric in the above range in this way, the highly absorbent polymer 12 is dispersed between the raised fibers 11x of the second air-through non-woven fabric, and it becomes easy to fix and support the second air-through non-woven fabric. ..

(Highly absorbent sheet)
As shown in FIG. 2, the highly absorbent sheet 10 used for the absorber 1 of the present embodiment is fixedly supported between the base nonwoven fabric 11 having a raised surface 11a on one side and the fibers 11x of the raised portion of the substrate nonwoven fabric 11. It has a highly absorbent polymer 12. The highly absorbent polymer 12 is dispersed and fixedly supported between the fibers 11x of the raised portion of the substrate nonwoven fabric 11, and the body fluid such as urine is appropriately diffused or held in the substrate nonwoven fabric 11 around the highly absorbent polymer 12. , Absorption performance is improved, and sufficient absorption performance can be ensured without having fluff pulp.

(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, a (starch / acrylic acid) graft copolymer, ( Examples thereof include a copolymer (acrylic acid / vinyl alcohol), a copolymer (isobutylene / maleic anhydride), and a saponified product thereof. Among these, polyacrylate 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 is preferably ^{200 g / m 2} or more and 1200 g / m ² or less from the viewpoint of ensuring the absorption performance required for various absorbent articles. Further, from the viewpoint of further improving the absorption performance, the feel after absorption, and the ease of movement of the wearer, the basis weight of the highly absorbent polymer 12 is more preferably ^{300 g / m 2} or more and 900 g / m ^{2 or less.}

Further, by avoiding the use of the fine powder high-absorbent polymer 12 having poor fluidity as a powder, the basic performance regarding absorption is improved, and the rugged tactile sensation generated by the hardening of the high-absorbency sheet 10 is achieved. The medium particle size of the highly absorbent polymer 12 is preferably 50 μm or more and 600 μm or less, and more preferably 100 μm or more and 500 μm or less.

The highly absorbent polymer 12 is preferably fixedly supported between the fibers 11x of the raised portion of the base nonwoven fabric 11 by a hot melt adhesive, and has high absorbency when the basis weight of the substrate nonwoven fabric 11 is relatively low. Hot melt adhesives work particularly well to reinforce the fixation and support of the polymer 12. The content of the hot melt adhesive is preferably ^{10 g / m 2} or less so as not to impair the absorbency of the highly absorbent polymer 12 and not to impair the feel when worn. Examples of the hot melt adhesive include synthetic rubber-based copolymers such as styrene-butadiene-styrene-based copolymers and styrene-isoprene-styrene-based copolymers having a melting point of 100 ° C. or higher and 180 ° C. or lower, or ethylene-vinyl acetate copolymers. Styrene-based hot melt adhesives such as the above can be used. As a method for applying the hot melt adhesive, known methods such as a curtain coating method in which the hot melt adhesive in a molten state is applied from a nozzle in a non-contact manner, a spiral method, and a slot method in which the hot melt adhesive is applied by a contact method can be used.

(Hydrophilic sheet)
The absorber 1 of the present embodiment can prevent the highly absorbent polymer 12 from leaking to the outside of the absorbent body 1 by adhering the raised surface 11a of the highly absorbent sheet 10 and the hydrophilic sheet 20. It can also improve the feel when worn. As the hydrophilic sheet 20, the first air-through non-woven fabric having a bending stiffness of 0.02 gf · cm ² / cm or more and 0.6 gf · cm ² / cm or less is used. The function of the first air-through nonwoven fabric is as described above. The first air-through nonwoven fabric, it is preferable that the basis weight is to 20 g / ^{m 2} or more 100 m ² or less. When the raised surface 11a of the highly absorbent sheet 10 is adhered to the hydrophilic sheet 20, it is preferable to fix the highly absorbent sheet 10 and the hydrophilic sheet 20 by hot melt adhesive or heat embossing. ..

<Manufacturing method of absorber>
The method for producing the absorber 1 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 fibers of the raised portion of the substrate nonwoven fabric 11 with a hot melt adhesive or the like to obtain the highly absorbent sheet 10. Then, the raised surface side of the substrate nonwoven fabric 11 and the hydrophilic sheet 20 are adhered with a hot melt adhesive or the like to obtain an absorber.

(Back sheet)
The back sheet 30 may be formed by using a base material having a liquid impermeable property so that the body fluid held by the absorber 1 does not wet the clothes, and the resin film or the resin film and the non-woven fabric are laminated. It is formed from a material such as a composite sheet. The non-woven fabric used for the composite sheet is not particularly limited in the manufacturing method, and for example, a spunbonded non-woven fabric, a melt-blown non-woven fabric, a spunbonded non-woven fabric / melt-blow non-woven fabric, a composite non-woven fabric in which spunbond non-woven fabric / melt-blow non-woven fabric / spunbond non-woven fabric is laminated, and these. Examples include composite materials. Examples of the resin film include polyester, polyvinyl alcohol, polyethylene, polypropylene, and a composite film of polyethylene and polypropylene.

From the viewpoint of strength and workability, the basis weight of the back sheet 30 ^{is preferably 15 g / m 2} or more and 40 g / m ² or less. Further, in order to prevent stuffiness at the time of mounting, it is preferable that the back sheet 30 is provided with breathability. In order to provide the back sheet 30 with breathability, for example, a filler may be blended in the resin film of the base material, or the back sheet 30 may be embossed for perforation. Calcium carbonate can be mentioned as the filler, and a known method can be used without limitation as the blending method.

(Three-dimensional gather)
Further, as shown in FIG. 1, the absorbent article 50 has both end portions of the skin side surface of the top sheet 25 along the longitudinal direction of the absorbent article 50 in order to prevent lateral leakage of the body fluid excreted by the user. A pair of three-dimensional gathers 40 are provided. One end of the three-dimensional gather 40 in the width direction of the absorbent article 50 is fixed near both side ends of the skin side surface of the back sheet 30 (or near both side ends of the non-skin side surface), and the middle portion in the width direction is the top. The three-dimensional gather sheet is arranged so as to be fixed near both side ends of the skin side surface of the sheet 25 and the other end in the width direction is a free end 40a which is not fixed to the top sheet 25. By providing an elastic elastic member for three-dimensional gathers (not shown) in the vicinity of the free end 40a along the longitudinal direction, the free end 40a of the three-dimensional gather 40 is provided with erectability and can be deformed according to the wearer's body shape. It becomes a thing. The fixed positions of one end in the width direction of the three-dimensional gather 40 are, for example, both ends in the width direction of the non-skin side surface of the back sheet 30, both ends in the width direction of the bag body in which the top sheet 25 and the back sheet 30 are partially or wholly joined. Both ends in the width direction of the skin side surface of the top sheet 25 and the like can be mentioned.

As the elastic member for three-dimensional gather, for example, a polyurethane thread, a band-shaped polyurethane film, a thread-like or band-shaped natural rubber, or the like is used, and as the three-dimensional gather sheet, water repellency or liquid impermeable formed of hydrophobic fibers. Non-woven fabrics such as spunbonded non-woven fabrics, melt-blown non-woven fabrics, spunbonded non-woven fabrics / melt-blow non-woven fabrics / spunbonded non-woven fabrics, and the like are used.

<Manufacturing method of absorbent articles>
The absorbent article 50 can be manufactured by a known manufacturing method. For example, a step of arranging the absorber 1 between the top sheet 25 and the back sheet 30 and a part or all of the top sheet 25 and the back sheet 30 are used. Manufacturing including a step of fixing with hot melt adhesive, heat embossing, ultrasonic embossing, high frequency embossing, etc. over the circumference, and a step of installing a three-dimensional gather 40 at predetermined positions of the back sheet 30 and the top sheet 25. The method can be mentioned. 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 can be provided as needed.

The absorber 2 shown in FIG. 5 is a modified example of the absorber 1. The absorber 2 uses the same substrate non-woven fabric 11, the highly absorbent polymer 12, and the hydrophilic sheet 20 as the absorber 1, and the hydrophilic sheet 20 is stretched in the width direction, and both end surfaces 20a and 20b in the width direction are formed. The substrate non-woven fabric 11 is configured to overlap on the top sheet 25 side. Due to the presence of the overlapping portion of the hydrophilic sheet 20 (hereinafter, also referred to as “overlapping region”), the absorber 2 not only exhibits an effect equal to or higher than that of the absorber 1, but also has a higher diffusion rate and absorption rate of the body fluid. The advantage of being even higher is obtained.

The width dimension of the overlapping region in the absorber 2 is preferably 5% or more and 50% or less of the width dimension D of the absorber 2. If it is less than 5%, the effect of improving the diffusion rate and absorption rate of body fluid tends to be insufficient even if the overlapping region is provided. On the other hand, if it exceeds 50%, the diffusion rate and absorption rate of the body fluid do not improve, but the hardness of the absorber tends to increase and the fit tends to deteriorate.

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. It will be apparent to those skilled in the art that improvements can be made. Further, it is clear from the description of the scope of claims that the form to which such a modification or improvement is added may be included in the technical scope of the present invention.

Hereinafter, the present invention will be described in detail with reference to examples. The present invention is not limited to the examples shown below.

(Example 1)
First, an air-through non-woven fabric (basis weight 30 g / m ² , bending rigidity 0.018 gf · cm ² / cm, width dimension 60 mm, longitudinal dimension 400 mm) is prepared, and one side surface of the substrate non-woven fabric is rotated. Physically brushed with a saw blade (thickness after brushing 1.2 mm, brushed rate 25%), highly absorbent polymer is dispersed (basis weight 400 g / m ² ), and the substrate non-woven fabric is brushed with a hot melt adhesive. A highly absorbent sheet was obtained by fixing and supporting it between the fibers of the woven fabric. Further, an air-through non-woven fabric (basis weight 35 g / m ² , flexural rigidity B of 0.031 gf · cm ² / cm, width dimension 140 mm, longitudinal dimension 400 mm) is prepared as a hydrophilic sheet, and the raised surface of the substrate non-woven fabric is prepared. The side and the hydrophilic sheet coated with the hot melt adhesive were adhered. Next, the hydrophilic sheet is folded in three, both ends of the hydrophilic sheet are overlapped above the non-raised surface of the substrate non-woven fabric, and the overlapping area is fixed with a hot melt adhesive. The entire raised surface, both end faces in the width direction, and the entire non-raised surface were covered to obtain an absorber of Example 1.

(Example 2)
An absorber of Example 2 was prepared in the same manner as in Example 1 except that an air-through non-woven fabric having a basis weight of 25 g / m ² and a flexural rigidity of 0.021 gf · cm ^{2 / cm was used as the hydrophilic sheet.}

(Example 3)
An absorber of Example 3 was prepared in the same manner as in Example 1 except that an air-through non-woven fabric having a basis weight of 70 g / m ² and a flexural rigidity of 0.090 gf · cm ^{2 / cm was used as the hydrophilic sheet.}

(Example 4)
An absorber of Example 4 was prepared in the same manner as in Example 1 except that an air-through non-woven fabric having a basis weight of 100 g / m ² and a flexural rigidity of 0.19 gf · cm ^{2 / cm was used as the hydrophilic sheet.}

(Example 5)
A highly absorbent sheet obtained by using an air-through non-woven fabric having a width direction of 90 mm is arranged as a hydrophilic sheet, the hydrophilic sheet is folded in three, and the raised surface, both side end faces in the width direction, and non-brushed surface of the base non-woven fabric are used. An absorber of Example 5 was prepared in the same manner as in Example 1 except that regions of 15 mm each in the width direction from both side ends of the surface were covered with a hydrophilic sheet and fixed with a hot melt adhesive. In this absorber, the non-raised surface of the base non-woven fabric extending in the longitudinal direction with a width of 60 mm was exposed at the central portion in the width direction.

(Comparative Example 1)
An absorber of Comparative Example 1 was prepared in the same manner as in Example 1 except that an air-through non-woven fabric having a basis weight of 150 g / m ² and a flexural rigidity of 0.67 gf · cm ^{2 / cm was used as the hydrophilic sheet.}

(Comparative Example 2)
An air-through non-woven fabric with a basis weight of 35 g / m ² and a flexural rigidity of 0.031 gf · cm ² / cm is used as the base non-woven fabric, and a hydrophilic sheet with a basis weight of 30 g / m ² and a flexural rigidity of 0.018 gf · cm ² / cm. An absorber was prepared in the same manner as in Example 1 except that the air-through non-woven fabric was used, and used as a sample of Comparative Example 2.

(Comparative Example 3)
An air-through non-woven fabric with a basis weight of 150 g / m ² and a flexural rigidity of 0.67 gf · cm ² / cm is used as the base non-woven fabric, and a hydrophilic sheet having a basis weight of 10 g / m ² and a flexural rigidity B of 0.005 gf · cm ² / cm. An absorber of Comparative Example 2 was prepared in the same manner as in Example 1 except that a cm spunbonded non-woven fabric was used.

(Comparative Example 4)
An absorber of Comparative Example 4 was prepared in the same manner as in Example 1 except that a substrate non-woven fabric having a width dimension of 60 mm and a hydrophilic sheet were used and arranged without folding.

(Comparative Example 5)
Air-through non-woven fabric (basis weight 20 g / m ² ) / high-absorbency polymer (basis weight 280 g / m ² ) / air-through non-woven fabric (basis weight 20 g / m ² ) / high-absorbent polymer (basis weight 100 g / m ² ) / span lace A sheet (all dimensions in the width direction were 60 mm) in which a non-woven fabric (basis weight 20 g / m ^{2) was laminated was used as an absorber.} The non-woven fabric used in Comparative Example 5 was not brushed like the substrate non-woven fabric used in Example 1.

[Measurement item]
The thickness, absorption rate, and amount of reversion were measured using the absorbers obtained in Examples 1 to 5 and Comparative Examples 1 to 5, and the results are shown in Table 1.
(Thickness)
The thickness of the center of the absorber was measured under no load condition and under a load condition of 35 gf / cm ^2.

(Absorption rate)
40 ml of 0.9 mass% physiological saline (37 ° C.) was poured into each of the absorbers of Examples 1 and Comparative Examples 1 to 5 ^{from a cylinder having an inner diameter of 30 mm under a pressure of 46 g / cm 2, and the physiological saline solution was added.} The time (seconds) until the substance 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.

(Amount of reversion)
200 ml of physiological saline was poured into the absorbers of Examples 1 and Comparative Examples 1 to 5, and 10 minutes after the water was poured, the filter paper was pressure-bonded to the surface of the absorber with a load of ^{35 gf / cm 2, and the filter paper was made into the filter paper in 1 minute.} Measure the amount of water that has returned. The smaller the amount of reversion, the drier the absorber.

(sensory evaluation)
Wearing a tape-stopping type disposable diaper using each absorber of Example 1 and Comparative Examples 1 to 3 with the cooperation of eight panelists who wear wheelchairs on a daily basis. Sensory evaluation was performed on the feeling (fitness, softness) and absorbency (presence or absence of leakage to the outside of the disposable diaper) by selecting "good" or "bad". The wearer used it for 8 hours and evaluated it in daily activities, and the results are shown in Table 1.
◎: When the number of wearers who chose “good” is 8 〇: When the number of wearers who chose “good” is 6 or more and 7 or less △: When the number of wearers who chose “good” is 3 or more and 5 people In the following cases ×: When there are one or two wearers who chose “good”, or when there is no wearer who chose “good”

(Operability)
〇: Normal production was possible without slowing down the operation speed.
Δ: The speed of operation decreased by 1% or more and 10% or less as compared with the normal case.
X: The operating speed decreased by more than 10% as compared with the normal case.

The flexural rigidity (flexural rigidity) of each non-woven fabric 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.) and setting them. 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 end the measurement at 0 curvature. In this way, a reciprocating curve of the bending moment with respect to the curvature of one cycle can be obtained. In the reciprocating curve of bending moment and the stiffness bending an average value of the slope between the slope between the curvature 0.5 cm ^-1 and 1.5 cm ^-1 curvature -0.5Cm ^-1 and -1.5Cm ^-1 ..

From Table 1, according to the configuration of the present embodiment, an absorber and an absorbent article having each item of returnability, absorption rate, softness, fit, leakage, and operability of body fluid at a high level can be obtained. Can be done.

1, 2 Absorbent 10 Highly absorbent sheet 11 Base non-woven fabric 11a Raised surface 11b Non-raised surface 11x Raised fiber 11X, 11Y Width direction end face 12 Highly absorbent polymer 20 Hydrophilic sheet 20a, 20b Width both ends of hydrophilic sheet 25 Top sheet 30 Back sheet 40 Three-dimensional gather 50 Absorbent article

Claims (6)

An absorbent article comprising a liquid-permeable top sheet, a liquid-impermeable back sheet, and an absorber disposed between the top sheet and the back sheet.
The absorber is
A base non-woven fabric having a brushed surface and a non-raised surface and arranged so that the non-raised surface faces the top sheet.
A highly absorbent sheet containing a highly absorbent polymer fixedly supported between the raised fibers on the raised surface of the base nonwoven fabric, and the like.
A hydrophilic sheet covering the raised surface of the substrate nonwoven fabric is provided.
The hydrophilic sheet is
An absorbent article comprising a first air-through non-woven fabric having a bending stiffness of 0.02 gf · cm ² / cm or more and 0.6 gf · cm ^{2 / cm or less.} The hydrophilic sheet is folded in three so that both end faces in the width direction face each other between the top sheet and the base non-woven fabric and cover both end faces in the width direction of the base non-woven fabric together with the raised surface of the base non-woven fabric. The absorbent article according to claim 1, which has a three-dimensional shape. The hydrophilic sheet is stretched in the width direction so that both ends in the width direction cover the non-raised surface of the substrate nonwoven fabric and overlap each other, and the overlapping width dimension is 5% or more and 50% or more of the width dimension of the absorber. % Or less, the absorbent article according to claim 1 or 2. The absorbent article according to any one of claims 1 to 3, wherein the first air-through nonwoven fabric has a basis weight of 20 g / m ² or more and 100 g / m ^{2 or less.} The substrate non-woven fabric is the second air-through non-woven fabric, the basis weight of the second air-through non-woven fabric is 20 g / m ² or more and 80 g / m ² or less, and the thickness of the fibers constituting the second air-through non-woven fabric is 1. The absorbent article according to any one of claims 1 to 4, which is 6.6 dtex or more and 14 dtex or less. The absorbent article according to any one of claims 1 to 5, wherein the highly absorbent polymer has a basis weight of 200 g / m ² or more and 1200 g / m ^{2 or less in the highly absorbent sheet.}

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