JP5995313B2 - Absorbent articles - Google Patents

Description

  The present invention relates to a thin and excellent absorbent article, and more particularly to a disposable light incontinence product that absorbs and retains excrement such as urine, a pants-type paper diaper, a urine pad, a tape-clamped paper diaper, and the like.

  A super absorbent polymer (Super Absorbent Polymer, hereinafter referred to as SAP) is a polymer that absorbs water several hundred times its own weight and gels and retains the water. Since the water once absorbed does not ooze out even when pressure is applied, SAP is suitable as a material for holding liquids for sanitary products such as disposable diapers and napkins.

As an absorbent laminate that is ultra-thin, does not lose shape after water absorption, and can sufficiently exhibit absorption capacity, it is a hot laminate in which two non-woven fabrics are provided between non-woven fabrics without pulp fibers other than non-woven fabrics. A configuration in which SAP powder is adhered to the hot melt adhesive while being adhered by a net layer made of a melt adhesive is disclosed (for example, see Patent Document 1).

JP 2004-106554 A

  An absorbent laminate having a structure in which a water-absorbing material composed of only SAP powder not containing pulp fibers is sandwiched between two nonwoven fabrics and bonded by hot melt as disclosed in Patent Document 1, that is, a Palpress SAP sheet It is an absorber which consists of (water absorption sheet).

  Such a Palpress SAP sheet can be reduced in thickness due to the high water absorption capability of SAP that can absorb water several hundred times its own weight. However, although SAP has a high water absorption capacity, the water absorption rate is slower than that of pulp. Therefore, when an SAP sheet is used for, for example, a paper diaper, urine leaks before SAP starts to suck, and gel blocking occurs repeatedly. There is a problem that it is necessary to add a layer made of airlaid or fluff pulp because problems such as deterioration in absorbability occur. Furthermore, even when these layers of airlaid or fluff pulp are added, there are problems that leakage from the front and rear, left and right, liquid return from the surface due to poor liquid absorption speed, stickiness, etc. may occur if they are simply stacked. It was.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a thin absorbent article having no dryness and high liquid absorption speed and high dryness.

In order to solve the above-mentioned problems, the absorbent article of the present invention is characterized by high water absorption between a top sheet made of a liquid-permeable sheet and a two-layer hydrophilic nonwoven fabric disposed below the top sheet. Resin sheet (SAP) particles fixed with hot melt, and the cross section in the width direction has a substantially Ω shape, and the cross section in the width direction arranged below the SAP sheet has a substantially Ω shape in the SAP sheet. In an absorbent composite consisting of an absorbent body comprising a pulp-containing hydrophilic sheet configured to be along, and a liquid-impermeable backsheet disposed below the absorbent body, the length of the absorbent article Three-dimensional gathers composed of a water-repellent nonwoven fabric and an elastic elastic member are disposed at both side edges in the direction, and the both ends of the top portion of the approximately Ω shape in the width direction of the SAP sheet are in the width direction of the SAP sheet at a plurality of locations in the longitudinal direction. The ends of both bottom portions of the substantially Ω shape in the width direction of the SAP sheet are respectively encased by corresponding ends of the bottom portions of the substantially Ω shape in the width direction of the pulp-containing hydrophilic sheet. The gist of this is

The top end portions of the approximately Ω shape in the width direction of the SAP sheet are joined to both bottom portions of the approximately Ω shape in the width direction of the SAP sheet at a plurality of locations in the longitudinal direction, and both the approximately Ω shape in the width direction of the SAP sheet are further joined. The SAP sheet and the pulp-containing hydrophilic sheet folded to the left and right at the center in the width direction by wrapping the end part of the bottom part with the corresponding end part of the substantially Ω-shaped bottom part in the width direction of the pulp-containing hydrophilic sheet. Each bent portion of the bottom of the Ω shape can be prevented from opening.

  The cross section in the width direction of the absorbent body composed of the SAP sheet and the pulp-containing hydrophilic sheet has a substantially Ω shape, and the absorbent body has a space surrounded by a bent portion having a substantially Ω shape. Thus, the diffusion of the liquid in the front-rear direction is promoted, and leakage from the side portion is prevented.

Since the absorbent body is composed of an SAP sheet and a pulp-containing hydrophilic sheet, the problem of a low SAP absorption rate is covered by the presence of pulp in the pulp-containing hydrophilic sheet having a high absorption rate. For this reason, the malfunction which leaks before SAP starts sucking a liquid does not arise.

The hydrophilic non-woven fabric of the SAP sheet is made of a synthetic fiber non-woven fabric and preferably has a basis weight of 20 g / m ² or more.

By arranging a flat plate-like second SAP sheet between the SAP sheet and the substantially Ω-shaped bottom part of the pulp-containing hydrophilic sheet, the absorbent capacity of the absorbent body can be increased. .

The content of the SAP particles is preferably from 100 to 1000 g / ^{m 2} in SAP sheet, more preferably ^{100~500g / m 2, 100~300g / m} 2 is most preferable.

The pulp-containing hydrophilic sheet is preferably made of hydronit or airlaid nonwoven fabric and preferably has a basis weight of 30 g / m ² or more.

According to the present invention, it is possible to provide a thin absorbent article having no dryness and high liquid absorption speed and high dry feeling.

It is an external view of the absorbent article which concerns on embodiment of this invention. (A) It is a disassembled perspective view of the absorber which concerns on embodiment of this invention. (B) It is a top view of the absorber which concerns on embodiment of this invention. It is sectional drawing of the width direction of the absorbent article which concerns on embodiment of this invention. It is sectional drawing of the width direction of the absorbent article which concerns on embodiment of this invention. It is sectional drawing of the width direction of the absorbent article which concerns on embodiment of this invention. It is sectional drawing of the width direction of the absorbent article which concerns on embodiment of this invention.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention (hereinafter referred to as embodiments) will be described in detail with reference to the accompanying drawings.

  In the present invention, “liquid” refers to a liquid containing a large amount of water, such as urine.

(First embodiment)
FIG. 1 is an external view of an absorbent article according to an embodiment of the present invention, FIG. 2 (a) is an exploded perspective view of an absorbent body according to the first embodiment of the present invention, and FIG. FIG. 3 is a plan view of the absorbent article according to the first embodiment of the present invention, and FIG. 3 is a cross-sectional view in the width direction of the absorbent article according to the first embodiment of the present invention. In FIG. 3, the joint portion 14 is not shown so that the configuration of the substantially Ω-shaped SAP sheet 11 a and the pulp-containing hydrophilic sheet 12 a can be clearly understood.

The absorbent body 1a includes a SAP sheet 11a having a substantially Ω-shaped cross section in the width direction, and a pulp that is disposed on the lower side of the SAP sheet 11a so that the cross-sectional shape in the width direction follows the approximately Ω shape of the SAP sheet 11a. Containing hydrophilic sheet 12a.
Specifically, SAP is sprinkled between 20 g / m ² of hydrophilic air-through nonwoven fabric at a basis weight of 300 g / m ² , and as a pulp-containing hydrophilic sheet 12 a at the bottom of the SAP sheet 11 a fixed with a hot melt adhesive. A 40 g / m ² hydronit made by Kimberly Clark is placed and folded so that the width direction is substantially Ω-shaped. At this time, the width of the top portion is 50 mm, the width of the bent portion A is 15 mm, the width of the enveloping portion B is 10 mm, the entire width is 150 mm, and the length can be 300 mm. In order to prevent the hydronit from being peeled off from the SAP sheet 11a, it is appropriately integrated with a hot melt adhesive. Further, as shown in FIG. 2 (b), a plurality of joint portions 14 extending in the longitudinal direction are provided at two positions on the left and right sides by hot embossing at positions spaced 50 mm forward and backward from the longitudinal center line of the absorbent body 1a.
Furthermore, the absorber 1a is arranged between the top sheet ^{2 made of} an air-through nonwoven fabric of 20 g / m ^{2 and} the back sheet 3 made of a polyethylene film of 20 g / m ² and bonded and integrated with a hot melt adhesive. At this time, the lower part of the top is not bonded to the back sheet 3 so that the bent part A opens to the body side when worn, and the top sheet, the bent part A and the vicinity thereof are not bonded.
Between the outer periphery of the absorbent body 1a and the outer periphery of the absorbent article, front, back, left and right flaps are provided by bonding the top sheet and the back sheet or the three-dimensional gather and the back sheet with a hot melt adhesive, and the absorbent body 1a is sealed. Stop. Thus, the absorbent article 7a having a width of 200 mm and a length of 360 mm can be obtained.

  Three-dimensional gathers 5 are disposed over the longitudinal direction at both ends in the width direction of the absorbent composite 4a.

Both ends of the top portion of the SAP sheet 11a in the width direction of the substantially Ω-shape are joined to both bottom portions of the SAP sheet 11a in the width direction of the SAP sheet 11a by hot embossing or hot melt at a plurality of joint portions 14 in the longitudinal direction. The ends of both bottoms of the substantially Ω shape in the width direction of the sheet 11a correspond to the bottoms of the substantially Ω shape in the width direction of the pulp-containing hydrophilic sheet 12a, as shown in the enveloping part B in FIG. Wrapped by the end to do.
Further, the approximately Ω-shaped top portion 11t of the SAP sheet 11a is bonded to the top sheet by hot melt, and at least in the approximately Ω-shaped bent portion A of the SAP sheet 11a and the vicinity thereof, the top sheet may not be bonded by hot melt. preferable. It is preferable that the back sheet side surface of the top portion of the approximately Ω shape of the SAP sheet 11a and the lower portion thereof are not joined to each other so as to form the space 13 when worn.

  The SAP sheet 11a is a sheet in which superabsorbent resin (SAP) particles are fixed by hot melt between two layers of hydrophilic nonwoven fabric (not shown), as shown in FIGS. 2 (a) and 3. In addition, it has a bent portion A that is folded left and right at the center in the width direction and is shaped into a substantially Ω shape with a flat top.

The basis weight of the hydrophilic nonwoven fabric constituting the SAP sheet 11a can be appropriately selected, but is preferably 20 g / m ² or more. If the basis weight of the hydrophilic nonwoven fabric is less than 20 g / m ² , there arises a problem that the liquid passes too rapidly through the hydrophilic nonwoven fabric. As a material for the hydrophilic nonwoven fabric, an air-through nonwoven fabric, a point bond nonwoven fabric, a spunbond nonwoven fabric, a spunlace nonwoven fabric, or the like made of a synthetic fiber such as polypropylene, polyethylene, or polyester can be used. In the present invention, an air-through nonwoven fabric that is particularly excellent in preventing liquid return is suitable.

  SAP is a polymer that has a network-like molecular structure, absorbs water several hundred times its own weight, swells in a gel state, and retains the water. SAP has a synthetic polymer system and a natural product-derived system, such as a polyacrylic acid system, a polysulfonic acid system, an acrylamide system, and a polyvinyl alcohol system as a synthetic polymer system, and a starch system, Cellulose and the like can be used, but are not particularly limited in the present invention.

The SAP content in the SAP sheet 11a is preferably 100 to 1000 g / m ² , more preferably 100 to 500 g / m ² , and most preferably 100 to 300 g / m ² . In order to prevent gel blocking (cohesion between swollen SAP particles) at the time of water absorption, the SAP layer is preferably thin, but when the SAP content is 100 g / m ² , the SAP sheet 11a Too little water absorption capacity. If the SAP content is 300 g / m ² or less, gel blocking does not occur. If SAP content is ^{300g / m 2 ~500g / m 2} , it can cause gel ^blocking, if it is ^{500g / m 2 ~1000g / m 2} , although the probability of causing gel blocking is even higher, SAP If the content is 1000 g / m ² or less, there is no practical problem. When the SAP content exceeds 1000 g / m ² , gel blocking tends to occur, which is not preferable. Further, in order to promote the diffusion of the liquid, it is desirable to heat emboss the surface of the SAP sheet 11a.

The pulp-containing hydrophilic sheet 12a is made of hydronit (made by Kimberly Clark, trade name), an airlaid nonwoven fabric, or the like, and preferably has a basis weight of 30 g / m ² or more. If the basis weight is less than 30 g / m ² , the water absorption capacity is inferior.

As disclosed in U.S. Pat. No. 5,284,703, Hydronit is made into a sheet by firmly entwining wood pulp with a polypropylene non-woven fabric at high water pressure (water jet) without using a binder (adhesive). It is a material with excellent strength and absorbency.

  The airlaid nonwoven fabric is formed by dispersing relatively short fibers such as pulp and heat-sealing fibers in the air at random using an air stream, forming them into a bulky sheet, and bonding them with a binder.

  As the liquid-impermeable sheet used for the back sheet 3, a breathable polyethylene film or a laminate of a breathable polyethylene film and a nonwoven fabric can be used, and the basis weight is not particularly limited.

  The three-dimensional gather 5 can be comprised from water-repellent nonwoven fabrics, such as a spun bond nonwoven fabric and a spun bond / melt blow composite material, and the basis weight thereof is not particularly limited.

A liquid diffusive sheet (not shown) can be provided between the top sheet 2 and the SAP sheet 11a of the absorber 1a in order to promote the diffusion of the liquid to the upper surface of the SAP sheet 11a. The liquid diffusion sheet preferably has a thickness of 0.5 mm or more, and an air-through nonwoven fabric, a point bond nonwoven fabric or a spunbond nonwoven fabric made of a synthetic fiber such as polypropylene, polyethylene or polyester having a basis weight of 25 g / m ² or more can be used. When the thickness is less than 0.5 mm or the basis weight is less than 25 g / m ² , the liquid is poorly diffused over the entire upper surface of the SAP sheet 11a. In this case, both ends of the top portion of the approximately Ω shape in the width direction of the SAP sheet 11a are joined to the lower surface of the liquid diffusable sheet with a hot melt adhesive over the longitudinal direction.

  The top sheet 2 and the back sheet 3 are fixed using a hot melt adhesive over the entire circumference. A method for applying the hot melt adhesive is not particularly limited, and there are a curtain coating method and a spiral method in which a molten adhesive is applied in a non-contact manner from a nozzle, and a known method such as a slot method can be applied to the contact method.

(Second Embodiment)
FIG. 4 is a cross-sectional view in the width direction of an absorbent article according to the second embodiment of the present invention. The bonding portion 14 is not shown so that the configuration of the approximately Ω-shaped SAP sheet 11a and the pulp-containing hydrophilic sheet 12a can be clearly understood.

  It is the same as that of 1st Embodiment except having further laminated | stacked flat SAP sheet 11b over the longitudinal direction between the substantially omega-shaped bottom part of SAP sheet 11a and pulp containing hydrophilic sheet | seat 12a.

The material and configuration of the SAP sheet 11b are the same as the material and configuration of the SAP sheet 11a, and the SAP content in the SAP sheet 11b is preferably 100 to 1000 g / m ² , more preferably, similar to the SAP sheet 11a. 100 to 500 g / m ² , most preferably 100 to 300 g / m ² .

  Thus, by laminating the SAP sheet 11b over the longitudinal direction on the lower side of the SAP sheet 11a, the water absorption capacity of the absorbent body 1b is increased compared to the configuration of the absorbent body 1a of the first embodiment, and the SAP particles There is no risk of gel blocking.

(Third embodiment)
FIG. 5 is a cross-sectional view in the width direction of an absorbent article according to a third embodiment of the present invention. The bonding portion 14 is not shown so that the configuration of the approximately Ω-shaped SAP sheet 11a and the pulp-containing hydrophilic sheet 12a can be clearly understood.

  A flat SAP sheet 11c is further laminated between the absorbent body 1a and the back sheet 3 in the longitudinal direction, and is the same as in the first embodiment except that it is folded inward at both ends in the width direction. Thereby, the absorption capacity is increased and the liquid return is further improved.

(Fourth embodiment)
FIG. 6 is a cross-sectional view in the width direction of an absorbent article according to the fourth embodiment of the present invention. The bonding portion 14 is not shown so that the configuration of the approximately Ω-shaped SAP sheet 11a and the pulp-containing hydrophilic sheet 12a can be clearly understood.

  Between the absorbent body 1a and the back sheet 3, a plate-shaped SAP sheet 11d and a pulp-containing hydrophilic sheet 12b (positioned on the back sheet side) are laminated in the longitudinal direction, and both ends in the width direction of the SAP sheet 11d contain pulp. It is the same as that of 1st Embodiment except having wrapped with the hydrophilic sheet | seat 12b. This increases the absorption capacity and further improves liquid return and diffusion.

The following has been clarified from the embodiment described above.
(A) By forming a pulp-containing hydrophilic sheet 12a made of hydronit, airlaid nonwoven fabric or the like into a substantially Ω shape and fitting it along the lower surface of the SAP sheet 11a, the SAP sheet 11a is less likely to be folded. Can be prevented.
(B) It is possible to prevent the SAP swelled in the wrapping part B at both ends in the width direction of the pulp-containing hydrophilic sheet 12a from falling off in the lateral direction, and the liquid that could not be absorbed by the SAP sheet 11a in the initial stage is contained in the pulp-containing hydrophilic sheet Since the sheet 12a absorbs and diffuses in the front and rear direction, side leakage can be prevented.
(C) In the absorbent articles 7a and 7b attached so that the top sheet 2 side comes into contact with the body, when the top sheet 2 is curved along the body side, the interval between the joint portions of the top sheet 2 and the SAP sheet 11a is increased. As the SAP sheet 11a is narrowed and pushed up toward the body, the fit is increased and the initial absorption is aided, so that the liquid uptake is enhanced.
(D) Even when excess liquid is discharged, the excess liquid that has passed through the SAP sheet 11a and the pulp-containing hydrophilic sheet 12a becomes an effective liquid guide path in the space 13 surrounded by the bent portion A. Since it flows in the direction, it does not leak out of the absorbent articles 7a and 7b.

  As mentioned above, although this invention was demonstrated using embodiment, it cannot be overemphasized that the technical scope of this invention is not limited to the range as described in the said embodiment. It will be apparent to those skilled in the art that various modifications or improvements can be added to the above embodiment. Further, it is apparent from the description of the scope of claims that embodiments with such changes or improvements can also be included in the technical scope of the present invention.

DESCRIPTION OF SYMBOLS 1a Absorber 2 Top sheet 3 Back sheet 4a Absorbing composite 5 Solid gather 6 Elastic elastic member 7a, 7b, 7c, 7d
Absorbent articles 11a, 11b, 11c, 11d
SAP sheet 11t Substantially Ω-shaped top portions 12a and 12b Pulp-containing hydrophilic sheet 13 Space 14 Joining portion A Bending portion B Enveloping portion

Claims (9)

A top sheet made of a liquid permeable sheet;
A mixture of highly water-absorbent resin (SAP) particles and hot melt adhesive is dispersed and held between two layers of hydrophilic nonwoven fabric disposed on the lower side of the top sheet, and the cross section in the width direction is substantially Ω-shaped. An absorbent body comprising: an SAP sheet, and a pulp-containing hydrophilic sheet that is disposed on the lower side of the SAP sheet and has a cross-sectional shape in the width direction configured to conform to the substantially Ω shape of the SAP sheet;
A liquid impervious backsheet disposed under the absorber;
In the absorbent composite comprising, a solid gather made of a water-repellent nonwoven fabric is disposed along the longitudinal direction at both ends in the width direction of the absorbent composite,
Both ends of the top portion of the approximately Ω shape in the width direction of the SAP sheet are joined to both bottom portions of the approximately Ω shape in the width direction of the SAP sheet at a plurality of locations over the longitudinal direction,
Ends of both bottom portions of the approximately Ω shape in the width direction of the SAP sheet are respectively wrapped by corresponding ends of the bottom portions of the approximately Ω shape in the width direction of the pulp-containing hydrophilic sheet. A sex product ,
The pulp-containing hydrophilic sheet is made of a sheet obtained by entwining wood pulp into a polypropylene nonwoven fabric without using a binder at a high water pressure, or an airlaid nonwoven fabric, and has a basis weight of 30 g / m ² or more. An absorbent article having:   The cross section in the width direction of the absorbent body composed of the SAP sheet and the pulp-containing hydrophilic sheet has a substantially Ω shape, and the absorbent body has a space surrounded by a bent portion having a substantially Ω shape. Absorbent article as described in 1. The absorbent article according to claim 1, wherein the hydrophilic nonwoven fabric of the SAP sheet is made of a synthetic fiber nonwoven fabric and has a basis weight of 20 g / m ² or more.   A flat second SAP sheet is further disposed between the SAP sheet and the substantially Ω-shaped bottom of the pulp-containing hydrophilic sheet to form an absorbent body. The absorbent article according to any one of the above.   A flat third SAP sheet is further laminated in the longitudinal direction between the absorber and the back sheet, and the third SAP sheet is folded inward at both ends in the width direction. Item 5. The absorbent article according to any one of Items 1 to 4.   Between the absorber and the back sheet, a flat fourth SAP sheet and a second pulp-containing hydrophilic sheet are laminated in the longitudinal direction in order from the absorber side, and the width direction of the fourth SAP sheet The absorbent article according to any one of claims 1 to 4, wherein both end portions are wrapped with the second pulp-containing hydrophilic sheet. Content of the said SAP particle in the said SAP sheet is 100-1000 g / m < ² >, The absorbent article of any one of Claims 1-6 characterized by the above-mentioned. The absorbent article according to claim 1, wherein the content of the SAP particles in the SAP sheet is 100 to 500 g / ^{m 2.} Content of the said SAP particle in the said SAP sheet is 100-300 g / m < ² >, The absorbent article of any one of Claims 1-8 characterized by the above-mentioned.

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