JP2014068813A - Absorber and absorbent article using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the thickness of an absorber while keeping the absorbing performance and to prevent deviation and falling of superabsorbent polymers.SOLUTION: An absorber 1 includes: a fibrous layer 2 formed by dispersing and mixing superabsorbent polymers 4 in an absorbent fiber 3; a polymer layer 5 formed of superabsorbent polymers 6, which is disposed on the lower layer side of the fibrous layer 2; a hydrophilic nonwoven fabric 7 interposed between the fibrous layer 2 and the polymer layer 5; and a core wrap sheet 8 surrounding a laminate of the fibrous layer 2, the polymer layer 5 and the hydrophilic nonwoven fabric 7. The lower surface side of the polymer layer 5 is fixed to the core wrap sheet 8 by full-coating of an adhesive 9, and the upper surface side thereof is fixed to the hydrophilic nonwoven fabric 7 by intermittent coating of an adhesive 10.

Description

  The present invention relates to an absorbent body used for absorbent articles such as disposable diapers, urine-absorbing pads, incontinence pads, and the like, and more particularly, an absorbent body that can be thinned while maintaining its absorbent performance, and an absorbent using the same. It relates to goods.

  Conventionally, since the body fluid absorbent articles such as disposable diapers, sanitary napkins, and incontinence pads have been provided on the market, various improvements have been accumulated with respect to absorbent bodies using a superabsorbent resin.

  As is well known, a highly water-absorbent resin absorbs and swells when it comes in contact with water and becomes a gel, and once absorbed, it has the property that it does not release even if a certain amount of pressure is applied. It shows tremendous water absorption such as reaching tens to thousands of times.

  Although the high water-absorbent resin alone exhibits the above-described absorption power, it cannot exhibit water absorption power unless it is moistened to some extent, and because the absorption speed is slow, the pulp fiber constituting the absorbent body of the body fluid absorbent article For example, it is mixed in the form of granular powder, crushed powder or pellets.

  In recent years, in the case of a relatively bulky absorbent article using this type of pulp fiber, there is a problem that it is difficult to obtain fit when attached, or the breathability is poor and stuffiness occurs, Due to the inconvenience of carrying, poor storage properties, demand for logistics efficiency and resource saving, etc., thinning and compacting have been attempted. When thinning the absorbent article, it is not possible to reduce the amount of water absorption even if it is made thin or compact, inevitably reducing the amount of pulp and increasing the content of the superabsorbent resin, In this case, (1) Occurrence of unevenness or dropout of the superabsorbent resin and the resulting decrease in absorption performance, (2) Occurrence of roughness due to the superabsorbent resin, (3) Deterioration of operability (on the line (4) By reducing the amount of pulp, the diffusion of liquid inside the absorber is reduced, causing problems such as reduced absorption performance due to gel blocking, etc. It was easy.

  As a technique for preventing a decrease in absorption performance of an absorbent body containing such a highly water-absorbent resin, in Patent Document 1 below, an absorbent body comprising a water-absorbing polymer having a predetermined amount of absorption under pressure The absorbent body comprises an upper absorbent layer made of a fiber mixture of a superabsorbent polymer and a fibrous material, and the superabsorbent polymer and the fibrous material disposed on the non-skin contact surface side of the upper absorbent layer An absorbent article comprising a lower absorbent layer made of a fiber mixture is disclosed.

  Moreover, in the following patent document 2, in the absorbent article which consists of an absorber of upper and lower two layers, the said absorber is a top absorbent body which mixes cotton-like pulp and an absorbent material, and the lower layer on a support body. An absorbent article comprising a lower absorbent body to which an absorbent substance is adhered and fixed is disclosed.

  Furthermore, Patent Documents 3 and 4 listed below disclose an absorbent product that includes a nonwoven fabric layer or a paper layer and a fiber web layer, and SAP particles are supported on the fiber web layer.

JP 2009-72220 A Japanese Unexamined Patent Publication No. 2000-24033 JP 2003-103740 A Japanese Patent Application Laid-Open No. 2003-103677

  However, in the absorbent article described in Patent Document 1, since the upper absorbent layer and the lower absorbent layer are both composed of a fiber mixture of a superabsorbent polymer and a fibrous material, it is difficult to reduce the thickness. Met. In addition, if the amount of the fibrous material is reduced to reduce the thickness, the proportion of the superabsorbent polymer inevitably increases, which may cause various problems such as the bias or dropping of the superabsorbent polymer as described above. Concerned.

  Further, in the absorbent article described in Patent Document 2, since the lower absorbent body made of the superabsorbent resin is arranged directly below the upper absorbent body in which the superabsorbent resin is dispersed and mixed in the pulp, When the absorber is thinned, the body fluid absorbed by the upper absorbent body is slightly diffused by the cotton-like pulp contained in the upper absorbent body, but is concentrated in a narrow range of the lower absorbent body. As a result, the absorption performance may be deteriorated due to a decrease in the temperature or the occurrence of reversal.

  Furthermore, in the absorbent article described in Patent Document 2, a lower absorbent body made of a superabsorbent resin is illustrated as being directly fixed to the back sheet without being surrounded by crepe paper or the like. The configuration is such that the resin tends to be biased or dropped. In addition, a form in which a liquid-permeable film is joined in a bag shape as a lower absorbent body in the lower layer and a superabsorbent resin is fixed inside the pouch is illustrated, but in this form, the superabsorbent resin is prevented from falling off. Although the water-absorbent resin that has absorbed water and swelled inside the bag shape is compressed by the outer film and easily adheres to the surrounding water-absorbent resin, gel blocking is likely to occur, There is concern about the decline.

  Moreover, since the fibrous web layer carrying SAP particles is not surrounded by crepe paper or the like in the absorbent products described in Patent Documents 3 and 4, the fibrous web layers are rubbed together when the absorbent product is folded. Then, when the SAP particles absorb water during use, the SAP particles may drop and move. In particular, when the absorbent product is used in a disposable diaper, the diaper product is bent at the crotch portion, so that the dropped SAP particles concentrate on the crotch portion and rise in a groovy shape, resulting in poor comfort. was there.

  Accordingly, a main problem of the present invention is to provide an absorbent body that can reduce the thickness of the absorbent body while maintaining the absorbent performance, and that prevents the highly water-absorbent resin from being biased or dropped off, and an absorbent article using the absorbent body. There is.

  In order to solve the above-mentioned problems, the present invention according to claim 1 includes a fibrous layer in which a highly water-absorbent resin is dispersed and mixed in a water-absorbing fiber, and a highly water-absorbing material disposed on the lower layer side of the fibrous layer. A polymer layer made of a hydrophilic resin, a hydrophilic nonwoven fabric interposed between the fibrous layer and the polymer layer, and a core wrap sheet surrounding the laminate of the fibrous layer, the polymer layer and the hydrophilic nonwoven fabric. An absorbent body is provided.

  In the first aspect of the invention, the highly water-absorbent resin contained in the absorbent is dispersed and mixed in the water-absorbing fibers (pulp, etc.) of the fibrous layer and disposed on the lower layer side of the fibrous layer. Since the polymer layer is arranged separately from those constituting the polymer layer, even when the amount of water-absorbing fibers in the fibrous layer is reduced due to the thinning of the absorber, it is dispersed and mixed in the fibrous layer. Various problems such as biasing or dropping off of the superabsorbent resin due to the high superabsorbent resin content in the water absorbent fiber, without excessive increase in the superabsorbent resin content, and poor absorption performance Will not occur. Therefore, it is possible to reduce the thickness of the absorber while maintaining the absorption performance.

  Moreover, since the inside of the absorber is divided into an upper fiber layer and a lower polymer layer, and a hydrophilic nonwoven fabric is interposed between the fibrous layer and the polymer layer, the upper fiber When passing through a hydrophilic non-woven fabric in the process of transferring body fluid from the base layer to the lower polymer layer, the body fluid is diffused over a wide area and can be absorbed by the superabsorbent resin over a wide range of the lower polymer layer become. Therefore, the body fluid does not concentrate in a narrow range of the polymer layer, and accordingly, it is possible to prevent the absorption performance from deteriorating due to a decrease in water absorption or reversal. Further, since the superabsorbent resin of the fibrous layer is dispersed and mixed in the superabsorbent fiber, the superabsorbent resin of the polymer layer can be prevented from being biased or dropped off and the superabsorbent polymer of the polymer layer can be separated from the hydrophilic nonwoven fabric. Since it is provided so as to be sandwiched between the core wrap sheet, it is possible to prevent the superabsorbent resin from being biased or dropped off, and even if the superabsorbent resin absorbs water and swells, the superabsorbent resin is compressed. Since there are few, it becomes difficult to produce the fall of the amount of water absorption by gel blocking.

  Furthermore, since the superabsorbent resin of the polymer layer is sandwiched between the hydrophilic nonwoven fabric and the core wrap sheet and the whole is surrounded by the core wrap sheet, the absorbent body is used for a disposable diaper or the like. Even when folded at the crotch portion, the core wrap sheet is interposed inside the folded portion, so there is no rubbing between the fibrous layers, and it is included in the fibrous layer and the polymer layer even after water absorption of the superabsorbent resin. The superabsorbent resin can be prevented from falling off and moving, and the superabsorbent resin can be maintained in a dispersed arrangement in each layer, so that even when the superabsorbent resin absorbs water and swells, the feeling of wearing does not deteriorate. .

  As the present invention according to claim 2, the polymer layer is fixed to the core wrap sheet on the lower surface side by applying the entire surface of the adhesive, and the upper surface side is fixed to the hydrophilic nonwoven fabric by intermittent application of the adhesive. The described absorber is provided.

  The invention according to claim 2 stipulates a fixing method of the polymer layer, wherein the lower surface side is fixed to the core wrap sheet by the entire surface application of an adhesive, and the upper surface side is fixed by the intermittent application of the adhesive. Fixed to the non-woven fabric. That is, the polymer layer is sandwiched between the core wrap sheet and the hydrophilic non-woven fabric, and the upper and lower surfaces are respectively fixed by the adhesive. This prevents the highly water-absorbent resin from being biased or dropped off in the polymer layer. Also, it firmly adheres to the core wrap sheet on the lower surface side by applying the entire surface of the adhesive, and adheres to the hydrophilic nonwoven fabric on the upper surface side so as not to prevent the transfer of body fluids by intermittent application of the adhesive. Yes.

  As the present invention according to claim 3, there is provided the absorbent body according to any one of claims 1 and 2, wherein the hydrophilic nonwoven fabric is formed in an uneven shape by being embossed.

  In the invention described in claim 3, since the hydrophilic nonwoven fabric is embossed to form the hydrophilic nonwoven fabric in a concavo-convex shape, the permeability of body fluid due to the difference in fiber density is improved, and the upper fibrous layer Thus, it is possible to easily draw body fluid from the polymer layer to the lower polymer layer, and the absorption performance is improved. In addition, since the superabsorbent resin of the polymer layer is intermittently pressed at the concave portion on the upper surface side of the hydrophilic nonwoven fabric, the superabsorbent resin becomes difficult to move and the bias of the superabsorbent resin can be prevented. .

  As this invention which concerns on Claim 4, the part adjacent to the said polymer layer and the said hydrophilic nonwoven fabric among the said core wrap sheets are each formed in the uneven | corrugated shape by embossing. An absorber according to any one is provided.

  In the invention of claim 4, hydrophilicity is obtained by embossing each of the core wrap sheet adjacent to the polymer layer and each of the hydrophilic nonwoven fabric to form each sheet in an uneven shape. Since the superabsorbent resin of the polymer layer is pressed intermittently at the concave portion on the upper surface side of the nonwoven fabric and the convex portion on the upper surface side of the core wrap sheet, the superabsorbent resin sandwiched between them is further increased. It becomes difficult to move, and the bias of the superabsorbent resin can be prevented.

  As the present invention according to claim 5, the liquid flow rate under pressure of the superabsorbent resin contained in the fibrous layer is relatively higher than the liquid flow rate under pressure of the superabsorbent resin constituting the polymer layer. The absorber according to any one of claims 1 to 4, which is set to be large.

  The invention according to claim 5 is intended to increase the water absorption efficiency by changing the type of the superabsorbent resin contained in the fibrous layer and the type of the superabsorbent resin constituting the polymer layer. . Specifically, the underflow rate of the superabsorbent resin contained in the fibrous layer is set to be relatively larger than the underflow rate of the superabsorbent resin constituting the polymer layer. Thus, liquid is passed through the upper fiber layer quickly, and water is efficiently absorbed by this polymer layer while suppressing diffusion in the lower polymer layer.

  As an aspect of the present invention according to claim 6, the absorbent layer according to any one of claims 1 to 5, wherein the fibrous layer is formed in a smaller area than the polymer layer, and is disposed at a substantially central portion of the polymer layer. Is provided.

  The invention according to claim 6 shows the first arrangement pattern of the fibrous layer and the polymer layer, wherein the fibrous layer is formed in a smaller area than the polymer layer, and is substantially at the center of the polymer layer. It is made to arrange | position to. As a result, the fiber layer becomes a middle middle and high part in the center, and the fit with the body fluid discharge site can be improved, and the absorption speed can be maintained because the fiber layer having the water-absorbing fibers is disposed in the body fluid discharge part. In addition, a predetermined amount of absorption can be secured by the lower polymer layer.

As the present invention according to claim 7, the polymer layer is a divided polymer layer divided into left and right at the longitudinal center line position of the absorber or in the vicinity thereof,
The absorbent body according to any one of claims 1 to 5, wherein the fibrous layer is formed so as to be narrower than the polymer layer and is disposed so as to straddle a divided portion of the polymer layer.

  The invention according to claim 7 stipulates the second arrangement pattern of the fibrous layer and the polymer layer, and the polymer layer is divided into right and left at the longitudinal center line position of the absorber or in the vicinity thereof. A fiber layer having a width smaller than that of the polymer layer is disposed so as to straddle the divided portion using the divided polymer layer. Thereby, the fitting property to a crotch part increases and it becomes possible to improve absorption performance.

As the present invention according to claim 8, the polymer layer is formed in a stripe shape in which a polymer arrangement region and a separation portion are alternately arranged along a plurality of longitudinal directions with respect to the width direction,
The absorbent body according to any one of claims 1 to 5, wherein the fibrous layer is formed in a smaller area than the polymer layer, and is disposed in a substantially central portion of the polymer layer.

  In the invention according to claim 8, the polymer layer is formed in a striped pattern in which polymer disposition regions and spacing portions are alternately arranged along the longitudinal direction in the width direction, and the fibrous material The layer is formed in a smaller area than the polymer layer, and is arranged at the substantially central portion of the polymer layer. Since the polymer layer is formed in a stripe shape, the diffusibility in the longitudinal direction is increased in the polymer layer, and leakage in the width direction can be prevented.

  As the present invention according to claim 9, the polymer layer and the hydrophilic nonwoven fabric are provided so as to extend on both sides of the side edge of the fibrous layer, and the extending portions are respectively provided on the side edges of the fibrous layer. The absorbent body according to any one of claims 1 to 8, wherein the side edges of the polymer layer and the hydrophilic nonwoven fabric are located on the upper surface side of the fibrous layer by being folded so as to wrap around.

  In the invention according to the ninth aspect, the polymer layer and the hydrophilic nonwoven fabric are provided so as to extend on both sides of the side edge of the fibrous layer, and each of the extended portions is provided on the side of the fibrous layer. The side edges of the polymer layer and the hydrophilic non-woven fabric are positioned on the upper surface side of the fibrous layer by folding around the edge. For this reason, side leakage from the side edge of the fibrous layer can be reliably prevented.

As the present invention according to claim 10, in an absorbent article in which an absorber is interposed between a liquid-permeable top sheet and a back sheet,
An absorbent article characterized in that the absorbent body according to any one of claims 1 to 9 is used as the absorbent body.

  As described above in detail, according to the present invention, it is possible to reduce the thickness of the absorbent body while maintaining the absorption performance, and to prevent the highly absorbent resin from being biased or dropped off.

It is sectional drawing of the absorber 1 which concerns on this invention. (A), (B) is a top view of the hydrophilic nonwoven fabric 7. FIG. It is sectional drawing of the absorber 1 which concerns on another form. The 1st arrangement pattern of the fibrous layer 2 and the polymer layer 5 is shown, (A) is a top view, (B) is a side view. The 2nd arrangement pattern of the fibrous layer 2 and the polymer layer 5 is shown, (A) is a top view, (B) is a side view. The 3rd arrangement pattern of the fibrous layer 2 and the polymer layer 5 is shown, (A) is a top view, (B) is a side view. (A), (B) is sectional drawing which shows the manufacture point of the absorber 1 which concerns on another form. It is sectional drawing of the absorber 1 which concerns on another form. It is a partial fracture development view of disposable diaper N concerning the present invention. It is the XX arrow directional view of FIG.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[Absorber 1]
As shown in FIG. 1, the absorbent body 1 according to the present invention includes a fibrous layer 2 in which a superabsorbent resin 4 is dispersed and mixed in a water absorbent fiber 3 such as pulp fiber, and the fibrous layer 2. A polymer layer 5 made of a superabsorbent resin 6 disposed on the lower layer side, a hydrophilic nonwoven fabric 7 interposed between the fibrous layer 2 and the polymer layer 5, and the fibrous layer 2 and the polymer layer 5 And a core wrap sheet 8 that surrounds the laminated body of the hydrophilic nonwoven fabric 7. The absorbent body 1 is formed in an elongated rectangular shape that is long in the front-rear direction of the wearer when the planar shape is attached to the crotch part, or an hourglass shape in which both sides of the center are depressed, and the width dimension thereof extends to the crotch part. It is formed in a size that does not give the wearer a feeling of sticking by hitting.

The fibrous layer 2 uses, for example, a dispersion in which the superabsorbent resin 4 is dispersed in pulp fibers, or a mixture in which chemical fibers are mixed in the pulp fibers and the superabsorbent resin 4 is dispersed. Can do. Basis weight of the fibrous layer 2 is preferably about 100 to 500 g / ^{m 2,} about 120~250g / ^{m 2} is more preferable. Examples of the pulp fibers include cellulose fibers such as chemical pulp obtained from wood, molten pulp, and tow fibers such as rayon and acetate. Softwood pulp having a longer fiber length than functional hardwood pulp functions and It is preferably used in terms of price.

  Examples of the superabsorbent resin 4 include a cross-linked polyacrylate, a self-crosslinked polyacrylate, a saponified acrylate-vinyl acetate copolymer cross-linked product, and a cross-linked isobutylene / maleic anhydride copolymer. , A crosslinked polysulfonate, and a partially crosslinked water-swellable polymer such as polyethylene oxide and polyacrylamide. Among these, those based on acrylic acid or acrylate that are excellent in water absorption and water absorption speed are preferred. The water-absorbing resin having the water-absorbing performance can be adjusted in water absorption (absorption capacity) and water absorption speed by adjusting the cross-linking density and the cross-linking density gradient in the production process.

  The content ratio of the superabsorbent resin 4 in the fibrous layer 2 is preferably 65% or less, more preferably about 30 to 50%, but is not limited thereto. When the content ratio of the superabsorbent resin 4 in the fibrous layer 2 is higher than 65%, the superabsorbent resin 4 is more likely to drop off, causing a bias before urination, and the contact between the superabsorbent resins 4 is increased. Blocking is likely to occur, resulting in a decrease in water absorption and absorption speed. In addition, in the absorbent body 1 according to the present invention, the content of the superabsorbent resin 4 in the fibrous layer 2 is suppressed to 65% or less, and the superabsorbent resin 4 is prevented from falling off or being biased while including the polymer layer 5. In addition, the content ratio of the superabsorbent resin as the entire absorbent body 1 (fibrous layer 2 and polymer layer 5) can be made higher than 65%.

  The area of the fibrous layer 2 is not particularly limited. However, since the fibrous layer 2 has a faster body fluid diffusion speed than the polymer layer 5, the polymer layer 5 can be prevented from leaking around the legs due to side leakage. It is preferable that the width dimension is narrower than that.

The superabsorbent resin 6 constituting the polymer layer 5 can also be appropriately selected from the same superabsorbent resin 4 contained in the fibrous layer 2. The polymer layer 5 can be appropriately set so that the basis weight of the superabsorbent resin 6 is in the range of 10 g / m ^{2 to} 200 g / m ² . The range in which the absorption performance can be maintained at a level that does not give a feeling of roughness when touched is preferably 20 g / m ² or more and 80 g / m ² or less. The area of the polymer layer 5 is less than or equal to the area of the core wrap sheet 8, and the plane pattern can be appropriately determined so as to be introduced in various patterns in the subsequent stage.

  The polymer layer 5 is fixed to the core wrap sheet 8 by applying the entire surface of an adhesive 9 such as a hot melt adhesive on the lower surface side, and the hydrophilic nonwoven fabric 7 by intermittently applying an adhesive 10 such as a hot melt adhesive on the upper surface side. It is fixed to. That is, the polymer layer 5 is bonded and fixed to the hydrophilic nonwoven fabric 7 and the core wrap sheet 8, respectively, with the upper surface and the lower surface sandwiched between the hydrophilic nonwoven fabric 7 and the core wrap sheet 8. For this reason, it is possible to reliably prevent the highly water-absorbing resin 6 from being biased or dropped.

  Although the application pattern of the adhesives 9 and 10 is not particularly limited, the adhesive 9 on the lower surface side strengthens the adhesive force with the core wrap sheet 8 and prevents the superabsorbent resin 6 itself from being biased or dropped off. It is preferable to use a full application pattern such as a curtain, slot, or spray, and the adhesive 10 on the upper surface side may be an intermittent application pattern such as a summit spray or a spiral spray so as not to prevent passage of body fluid. Is preferred.

  The hydrophilic non-woven fabric 7 is a non-woven fabric excellent in diffusibility in the plane direction of body fluids. For example, cellulose fibers such as cotton and rayon, synthetic fibers having a hydrophilic group such as acrylonitrile and polyvinyl alcohol, polyethylene, polypropylene, etc. A polyolefin fiber, a fiber such as polyester that has been subjected to a surface treatment with a hydrophilizing agent to impart hydrophilicity can be used. In the case of using a hydrophilic surface-treated fiber with hydrophilic agent as the hydrophilic non-woven fabric 7, the outflow of the hydrophilic agent attached to the fiber is reduced, and the hydrophilicity does not decrease even when water is repeatedly permeated. It is preferable to use a nonwoven fabric made of durable hydrophilic fibers to which a hydrophilizing agent containing water-soluble modified silicon is attached.

  The hydrophilic non-woven fabric 7 is provided with a size at least equal to the formation range of the polymer layer 5, and as shown in FIG. 1, the edge extends slightly outward from the formation range of the polymer layer 5. It is preferable to be provided with different sizes. By disposing the hydrophilic nonwoven fabric 7 in such a size, the fibrous layer 2 can be formed in a smaller area than the polymer layer 5 as will be described in detail in the arrangement pattern of the fibrous layer 2 and the polymer layer 5 in the subsequent stage. Even when it is formed (see FIGS. 4 to 6), since the polymer layer 5 is covered with the hydrophilic nonwoven fabric 7, the gravel feeling of the superabsorbent resin 6 of the polymer layer 5 is not felt, and the texture and performance are impaired. Nothing will happen.

  Moreover, the hydrophilic nonwoven fabric 7 arbitrarily sets the material, basis weight, diffusibility, etc. of the hydrophilic nonwoven fabric 7 according to the water absorption power and water absorption speed of the upper fibrous layer 2 and the lower polymer layer 5. It is possible. For example, when the water absorption speed of the fibrous layer 2 is fast and the liquid quickly penetrates into the lower layer, the fiber density of the hydrophilic nonwoven fabric 7 is increased, and the diffusibility in the plane direction is increased by the capillary force of the fibers. Can be set as follows.

The method for producing the hydrophilic nonwoven fabric 7 is not limited, and a nonwoven fabric obtained by an appropriate processing method such as an air-through method, a spunbond method, a spunlace method, a thermal bond method, a melt blown method, or a needle punch method may be used. However, the air-through method and the spunbond method are suitable for making the texture soft. Similarly, in order to make the texture soft, the basis weight of the hydrophilic nonwoven fabric 7 is preferably 10 g / m ² or more and 40 g / m ² or less. The planar shape is preferably formed with an area larger than the area of the polymer layer 5.

As the core wrap sheet 8, a paper material such as tissue or a liquid-permeable sheet such as a nonwoven fabric can be used. However, the water-absorbing fibers 3 and the highly water-absorbing resin 4 contained in the fibrous layer 2 do not escape. It is preferable to use a fiber having a fiber density of. The thickness is preferably about 0.05 to 0.5 mm, more preferably about 0.05 to 0.2 mm. Basis weight is preferably about 5 to 25 g / ^{m 2,} about 5 to 15 g / ^{m 2} is more preferable. When using a non-woven fabric, a non-woven fabric processed by a spunbond method or an SMS method, particularly a non-woven fabric processed by an SMS method, is preferred because of its excellent balance between thinness and strength. The core wrap sheet 8 is not particularly limited in the hydrophilicity of the sheet as long as at least the surface side (skin contact surface side) of the absorbent body 1 is not water-repellent.

  According to the absorbent body 1 having the above-described configuration, as the highly water-absorbing resin contained in the absorbent body 1, the highly water-absorbing resin 4 dispersed and mixed in the water-absorbing fibers 3 of the fibrous layer 2, and this fiber The absorbent body 1 is arranged separately from the superabsorbent resin 6 constituting the polymer layer 5 disposed on the lower layer side of the layer 2. Even if the amount of the water-absorbing fiber 3 in the fibrous layer 2 is reduced for thinning and compacting, the content of the superabsorbent resin 4 dispersed and mixed in the fibrous layer 2 does not become extremely large. Of the superabsorbent fibers 4 due to the high content of the superabsorbent resin 4, the occurrence of unevenness and dropout of the superabsorbent resin 4 and the resulting decrease in absorption performance, the occurrence of a rough feeling due to the superabsorbent resin, operability Problems such as deterioration of the absorption performance due to deterioration of gel and gel blocking Kunar. Therefore, it is possible to reduce the thickness of the absorber while maintaining the absorption performance.

  Further, since the absorbent body 1 is divided into two absorbent layers of a fibrous layer 2 on the upper layer side and a polymer layer 5 on the lower layer side, and a hydrophilic nonwoven fabric 7 is interposed between these layers, the fibers on the upper layer side When the body fluid is transferred from the porous layer 2 to the lower polymer layer 5, the body fluid is diffused over a wide range when passing through the hydrophilic nonwoven fabric 7, and as a result, the lower polymer layer 5 has a wide range of superabsorbent resin 6. Can absorb water. Therefore, the absorption performance is not deteriorated due to a decrease in water absorption or reversal. In addition, since the superabsorbent resin 4 of the fibrous layer 2 is dispersed and mixed in the superabsorbent fiber 3, the superabsorbent resin 4 can be prevented from being biased or dropped off, and the superabsorbent resin of the polymer layer 5 can be prevented. 6 is sandwiched and fixed between the hydrophilic nonwoven fabric 7 and the core wrap sheet 8, so that the superabsorbent resin 6 can be prevented from being biased or dropped, and the superabsorbent resin 6 absorbs water and swells. However, since the pressure between the highly water-absorbent resins 6 and 6 is small, it is difficult for the water absorption amount to decrease due to gel blocking.

  Further, the superabsorbent resin 6 of the polymer layer 5 is sandwiched between the hydrophilic nonwoven fabric 7 and the core wrap sheet 8, and the entire laminate of the fibrous layer 2, the hydrophilic nonwoven fabric 7 and the polymer layer 5 is the core. Since it is surrounded by the wrap sheet 8, even when the absorbent body 1 is used in a disposable diaper or the like and folded at the crotch portion, the upper core wrap sheet 8 is interposed inside the folded portion, and the folded portion The fiber layers 2 are not rubbed together, and the superabsorbent resins 4 and 6 contained in the fibrous layer 2 and the polymer layer 5 are prevented from falling off and moving even after the superabsorbent resins 4 and 6 absorb water. In addition, since the superabsorbent resins 4 and 6 can be kept dispersed in the layers 2 and 5, even when the superabsorbent resins 4 and 6 absorb water and swell, the feeling of wearing does not decrease.

Next, a modification of the absorber 1 will be described.
As shown in FIG. 2, the hydrophilic nonwoven fabric 7 is embossed 7a, 7a, etc. in (A) lattice form or (B) linear form, thereby forming the hydrophilic nonwoven fabric 7 itself in an uneven shape. be able to. By forming the hydrophilic non-woven fabric 7 in a concavo-convex shape, a fiber density difference is generated, and this density difference makes it easier for body fluid to be drawn from the upper fibrous layer 2 to the lower polymer layer 5, thereby improving the absorption performance. Further, since the superabsorbent resin 6 of the polymer layer 5 is intermittently pressed by the concave portion on the upper surface side (protruded portion on the lower surface side), the superabsorbent resin 6 becomes difficult to move, and the superabsorbent resin 6 Can be prevented.

  Further, as shown in FIG. 3, the adjacent portion 8a of the core wrap sheet 8 with the polymer layer 5 on the lower surface and the hydrophilic nonwoven fabric 7 can be formed in an uneven shape by embossing, respectively. is there. By forming the polymer layer adjacent portion 8a of the core wrap sheet 8 and the hydrophilic nonwoven fabric 7 in a concavo-convex shape, a concave portion on the upper surface side of the hydrophilic nonwoven fabric 7 in addition to the effect of drawing bodily fluids due to the above-described fiber density difference The superabsorbent resin 6 of the polymer layer 5 can be intermittently pressed at the convex portion on the upper surface side of the core wrap sheet 8 (the convex portion on the lower surface side), thereby further increasing the superabsorbent resin 6. It becomes difficult to move, and the bias of the superabsorbent resin 6 can be prevented. Moreover, when the core wrap sheet 8 is formed in a concavo-convex shape, it is possible to soften the feeling of texture from the outside. The embossing pattern of each sheet 8 and 7 can be a lattice or a line as in FIG. Moreover, when it forms with the pattern in which the recessed part of the said core wrap sheet | seat 8 and the convex part of the hydrophilic nonwoven fabric 7 correspond, it becomes possible to prevent the bias | inclination of the highly water-absorbing resin 6 further. Note that only the core wrap sheet 8 may be embossed to form an uneven shape. In this case, it is possible to prevent the superabsorbent resin 6 from being biased and to soften the touch from the outside. .

  The superabsorbent resin 4 contained in the upper fibrous layer 2 and the superabsorbent resin 6 constituting the lower polymer layer 5 may be the same type or different types having different properties. Can also be used. When composed of different types, the superabsorbent resin 4 contained in the fibrous layer 2 has a relatively high liquid passing rate under pressure in order to prevent gel blocking and prevent surface liquid residue (at 2.0 kPa). As the superabsorbent resin 6 constituting the polymer layer 5, one having a relatively low liquid passing rate under pressure (one less than 50 ml / min) can be used. As a result, liquid permeability in the upper fiber layer 2 is increased and diffusibility is improved, and body fluid is efficiently applied to the superabsorbent resin 6 while suppressing body fluid diffusion in the lower polymer layer 5. Can be absorbed.

As a method for measuring the liquid flow rate under pressure, a method according to the method for measuring the gel flow rate described in JP-A-2003-235889 can be used. Specifically, the liquid flow rate under pressure is as follows: a narrow tube (inner diameter: 4 mm, length: 8 cm) with a metal mesh (mesh opening: 150 μm) and a cock (inner diameter: 2 mm) at the lower end of a vertically standing cylinder (inner diameter: 25.4 mm). A 0.200 g measurement sample adjusted to a particle size of 850 to 150 μm in a state in which the cock is closed is put into a filtration cylindrical tube having a pressure of 25 ± 5 ° C. physiological saline (0.9 wt% sodium chloride aqueous solution). ) Pour 50 ml, let stand for 30 minutes after starting to pour, then insert a load (21.2 g) with a wire mesh (opening 150 μm, diameter 25 mm) into the filtration cylinder so that the wire mesh and measurement sample are in contact with each other, Later, a weight (77.0 g) was placed on a load with a wire mesh, left still for 1 minute, then the cock was opened, and the time until the saline level reached the 20 ml scale line from the 40 ml scale line ( 1) was measured in seconds, determined from the following equation. Here, (T0) is the time when there is no measurement sample.
Liquid passing speed under pressure (ml / min) = 20 × 60 / (T1-T0)

  Next, the arrangement pattern of the fibrous layer 2 and the polymer layer 5 will be described with reference to FIGS. 4 to 6 illustrate only the arrangement relationship between the fibrous layer 2 and the polymer layer 5, and omit the illustration of the hydrophilic nonwoven fabric 7 and the core wrap sheet 8, but the hydrophilic nonwoven fabric. 7 is provided in a range covering the polymer layer 5, and the core wrap sheet 8 is provided so as to surround these laminates.

  In the first arrangement pattern, as shown in FIG. 4, the fibrous layer 2 is formed in a smaller area than the polymer layer 5, and is arranged in the substantially central portion of the polymer layer 5. At this time, the superabsorbent resin 6 is disposed over the entire surface of the polymer layer 5. As described above, since the fibrous layer 2 having a smaller area than the polymer layer 5 is laminated only on the central portion of the polymer layer 5, the absorber 1 can be thinned, and the fibrous layer 2 is disposed at the center. Acts as a mid-high part and can improve the fit with the body fluid discharge part. Furthermore, since the fibrous layer 2 having the water-absorbing fibers 3 is disposed in the body fluid discharge part, the absorption speed can be maintained and the polymer layer 5 is provided with the superabsorbent resin 6 over the entire surface, so that a sufficient amount of absorption can be obtained. Can be secured. As the dimension of the fibrous layer 2, the longitudinal dimension is preferably about 40 to 85% of the longitudinal dimension of the polymer layer 5, and the width dimension is preferably about 35 to 85% of the width dimension of the polymer layer 5.

  Further, as shown in FIG. 5, the second arrangement pattern was divided into the left and right by the separation of the polymer layer 5 at or near the longitudinal center line position of the absorbent body 1. In addition to the divided polymer layers 5 a and 5 a, the fibrous layer 2 is formed to have a width smaller than that of the polymer layer 5, and is disposed so as to straddle the separation portion 5 b of the polymer layer 5. That is, a portion where the polymer layer 5 is not present on the lower layer side is formed along the longitudinal direction in the center portion in the width direction of the fibrous layer 2, and the divided polymer layers 5a and 5a are disposed on both sides thereof. For this reason, the fitting property to a crotch part can be improved with the fibrous layer 2 of the width direction center part, and absorption performance can be improved. Moreover, since the fibrous layer 2 has a width dimension shorter than that of the polymer layer 5, even when the fibrous layer 2 easily diffuses in the width direction, side leakage can be prevented. The width dimension of the fibrous layer 2 is preferably about 35% to 85% of the width dimension of the polymer layer 5. In this pattern, in the center in the width direction, the upper fiber layer 2 plays a role of absorbing body fluid, and the body fluid leaking from both sides of the upper fiber layer 2 is captured to prevent side leakage. A lower polymer layer 5 is provided.

  Furthermore, as shown in FIG. 6, the third arrangement pattern is such that the polymer layer 5 has alternating polymer arrangement regions 5a and separation portions 5b in which the superabsorbent resin 6 is not arranged in the width direction. A fibrous layer 2 formed in a striped pattern arranged along a plurality of longitudinal directions and having a smaller area than the polymer layer 5 is disposed at a substantially central portion of the polymer layer 5. Since the polymer layer 5 is formed in stripes, diffusion in the longitudinal direction is increased in the polymer layer 5 and leakage in the width direction can be prevented. Further, since the amount of the superabsorbent resin 6 used can be reduced, it is possible to reduce the cost by saving the material. The longitudinal dimension of the fibrous layer 2 is preferably about 40% to 85% of the longitudinal dimension of the polymer layer 5, and the width dimension of the fibrous layer 2 is preferably about 35% to 85% of the width dimension of the polymer layer 5. The width of one polymer arrangement region 5a of the polymer layer 5 is preferably 10 mm or more, and more preferably about 10 mm to 30 mm. In consideration of the diffusibility in the longitudinal direction, the width dimensions of the polymer arrangement region 5a and the spacing portion 5b are preferably substantially equal, and the number of the polymer arrangement regions 5a is about 3 to 7. It is preferable to do this.

  Next, as shown in FIG. 7, the polymer layer 5 and the hydrophilic non-woven fabric 7 are extended to both sides of the side edge of the fibrous layer 2, and the extending portions on both sides of the fibrous layer 2 are respectively The side edges of the polymer layer 5 and the hydrophilic nonwoven fabric 7 can be positioned on the upper surface side of the fibrous layer 2 by folding the side edges of the layer 2 from the lower side to the upper side. . Thereby, the leakage from the both side edges of the fibrous layer 2 can be completely prevented.

  By the way, as shown in FIG. 8, a hydrophilic nonwoven fabric 7B is disposed between the polymer layer 5 and the core wrap sheet 8, and the polymer layer 5 is divided into an upper hydrophilic nonwoven fabric 7 and a lower hydrophilic nonwoven fabric 7B. You may make it fix by inserting | pinching between. This makes it possible to reduce the gravel feeling (grainy feeling, graininess) of the polymer layer 5 when touched from the outer surface of the absorbent body, and the lamination in which the polymer layer 5 is sandwiched between the hydrophilic nonwoven fabrics 7 and 7B in advance. Since the body can be manufactured and then surrounded by the core wrap sheet 8, the manufacturing becomes easy.

  Next, the manufacturing method of the absorber 1 will be described. The adhesive 9 is applied to the central portion of the core wrap sheet 8 in the width direction, and the superabsorbent resin 6 is sprayed on the coated surface. Subsequently, the adhesive 10 is applied to the lower surface side of the hydrophilic nonwoven fabric 7, and the adhesive 10 is laminated on the upper surface on which the superabsorbent resin 6 is dispersed. Thereafter, the fibrous layer 2 in which the superabsorbent resin 4 is mixed in the water absorbent fiber 3 is laminated on the upper surface of the hydrophilic nonwoven fabric 7. Thereafter, both side portions of the core wrap sheet 8 are folded back on the upper surface of the fibrous layer 2 and surrounded so that the side edges overlap each other on the upper surface of the fibrous layer 2.

[Configuration of disposable diaper N using the absorbent body 1]
As shown in FIGS. 9 and 10, the disposable diaper N using the absorbent body 1 includes a liquid-permeable top sheet 11 made of a nonwoven fabric, a back sheet 12 made of polyethylene, and the liquid-permeable top sheet. 11 and the absorbent body 1 interposed between the back sheet 12, and the absorbent main body 13 having solid gathers BS and BS formed on both sides of the front surface and the outer surface side of the back sheet 12. The front body F and the rear body B of the exterior sheet 20 are joined at both side portions 21 and 22 in a product state, and thereby a waist opening and a pair of left and right leg openings. This is a pants-type diaper having a structure in which is formed.

  As the liquid-permeable top sheet 11 covering the surface side (skin contact surface side) of the absorbent body 1, a porous or non-porous nonwoven fabric or a porous plastic sheet is preferably used. The material fibers that make up the nonwoven fabric can be synthetic fibers such as olefins such as polyethylene or polypropylene, polyesters, and polyamides, recycled fibers such as rayon and cupra, and natural fibers such as cotton. A nonwoven fabric obtained by an appropriate processing method such as a spun bond method, an SMS method, a thermal bond method, an air through method, a point bond method, a melt blown method, or a needle punch method can be used.

  As the back sheet 12 that covers the back surface side (non-skin contact surface side) of the absorbent body 1, a liquid-impervious plastic sheet such as polyethylene or polypropylene is used, but in recent years, it has moisture permeability from the viewpoint of preventing stuffiness. Are preferably used. This water-impervious / breathable sheet is a microporous sheet obtained by, for example, melt-kneading an inorganic filler in an olefin resin such as polyethylene or polypropylene to form a sheet, and then stretching in a uniaxial or biaxial direction. If the sheet thickness is the same, the rigidity is lower than that of the non-porous sheet, which is superior in terms of flexibility.

  On the other hand, the gathered non-woven fabric 16 forming the three-dimensional gather BS is a non-woven fabric made into a double sheet by folding, and the side edge portion of the absorbent body 1 entrapped by the liquid-permeable top sheet 11 is further entrapped from the upper side. It extends to the back side of the absorbent body 1 and is bonded. More specifically, the gathered nonwoven fabric 16 has a three-dimensional gather BS forming portion at the middle part in the longitudinal direction of the diaper, and a range extending from the widthwise middle part to the back side of the absorbent body 1 is bonded by a hot melt adhesive or the like. Further, at the longitudinal front and rear end portions, the section from the intermediate portion in the width direction to the one side end edge is bonded in a range extending to the back side of the absorbent body 1 and the portion forming the three-dimensional gather BS is absorbed by the absorbent body While being folded at the upper surface portion of 1, it is bonded by a hot melt adhesive or the like.

  In addition, on the lower surface side (absorber side) of the liquid-permeable top sheet 11, in order to increase the absorption speed of body fluid and prevent the body fluid from returning, the liquid-permeable top sheet 11 is interposed between the liquid-permeable top sheet 11 and the core wrap sheet 8. It is preferable to arrange a second sheet 18 made of a hydrophilic nonwoven fabric. The second sheet 18 may not be provided, but when disposed, the second sheet 18 is disposed between the liquid-permeable top sheet 11 and the core wrap sheet 8. The second sheet 18 is preferably disposed so as to cover almost the entire area of the absorbent body 1 so as to improve the permeability of body fluid and prevent reversal.

  Next, the structure of the exterior sheet 20 will be described in detail. The exterior sheet 20 is a non-woven sheet having a two-layer structure in which an upper layer non-woven fabric 20A and a lower layer non-woven fabric 20B are bonded with a hot melt adhesive or the like, and various elastic elastic members are hot between the upper layer non-woven fabric 20A and the lower layer non-woven fabric 20B. It is bonded with a melt adhesive or the like to give stretchability. The planar shape forms a pseudo hourglass shape as a whole by the concave leg circumference cut lines 29 for forming leg openings on both sides of the middle.

  The material fibers constituting the upper layer nonwoven fabric 20A and the lower layer nonwoven fabric 20B are not only the permeable topsheet 11 and the gathered nonwoven fabric 16, but also synthetic fibers such as polyethylene or polypropylene such as olefin, polyester and polyamide, and rayon. Natural fibers such as spunbond, SMS, meltblown, thermal bond, air through, point bond, needle punch, etc. Produced nonwoven fabrics can be used.

  In the exterior sheet 20, as the elastic elastic member, the waist elastic elastic members 24, 24... Disposed around the waist opening 23 and the front body F and the back body B are horizontally spaced with a vertical interval. A plurality of waist elastic elastic members 25, 25,... Are arranged along the direction to form shirring around the waist.

  The absorbent main body 13 and the exterior sheet 20 are integrated on the upper surface side of the exterior sheet 20 by bonding the absorbent main body 13 with an adhesive such as hot melt. And the absorptive main body 13 and the exterior sheet | seat 20 are folded up in the front-back direction, and the both sides are mutually joined by heat welding or a hot-melt-adhesive etc., and are assembled into the pants-type disposable diaper N.

[Other examples]
In the above embodiment, the disposable diaper has been described as an example, but the present invention can be widely used for absorbent articles such as a urine collection pad, an incontinence pad, and a sanitary napkin.

  DESCRIPTION OF SYMBOLS 1 ... Absorber, 2 ... Fiber layer, 3 ... Water absorbing fiber, 4 ... High water absorbing resin, 5 ... Polymer layer, 6 ... High water absorbing resin, 7 ... Hydrophilic nonwoven fabric, 8 ... Core wrap sheet, 9. DESCRIPTION OF SYMBOLS 10 ... Adhesive, 11 ... Liquid-permeable top sheet, 12 ... Back sheet, 16 ... Gathered nonwoven fabric, 18 ... Second sheet, 20 ... Exterior sheet

Claims (10)

  A fibrous layer in which a superabsorbent resin is dispersed and mixed in a superabsorbent fiber, a polymer layer made of a superabsorbent resin disposed on a lower layer side of the fibrous layer, the fibrous layer and the polymer layer, An absorbent body comprising a hydrophilic non-woven fabric interposed between and a core wrap sheet surrounding a laminate of the fibrous layer, the polymer layer, and the hydrophilic non-woven fabric.   2. The absorbent body according to claim 1, wherein the polymer layer has a lower surface side fixed to the core wrap sheet by an entire surface application of an adhesive and an upper surface side fixed to the hydrophilic nonwoven fabric by an intermittent application of an adhesive.   The absorbent body according to claim 1, wherein the hydrophilic nonwoven fabric is formed in an uneven shape by being embossed.   The absorbent body according to any one of claims 1 to 3, wherein a portion of the core wrap sheet adjacent to the polymer layer and the hydrophilic nonwoven fabric are each formed in an uneven shape by being embossed.   The liquid flow rate under pressure of the superabsorbent resin contained in the fibrous layer is set to be relatively larger than the fluid flow rate under pressure of the superabsorbent resin constituting the polymer layer. 4. Absorber in any one of 4.   The absorbent body according to any one of claims 1 to 5, wherein the fibrous layer is formed in a smaller area than the polymer layer, and is disposed at a substantially central portion of the polymer layer. The polymer layer is a divided polymer layer divided into left and right at the longitudinal center line position of the absorber or in the vicinity thereof,
The absorbent body according to any one of claims 1 to 5, wherein the fibrous layer is formed so as to be narrower than the polymer layer and is disposed so as to straddle a divided portion of the polymer layer. The polymer layer is formed in a stripe shape in which a polymer disposition region and a spacing portion are alternately arranged along the longitudinal direction with respect to the width direction,
The absorbent body according to any one of claims 1 to 5, wherein the fibrous layer is formed in a smaller area than the polymer layer, and is disposed at a substantially central portion of the polymer layer.   The polymer layer and the hydrophilic non-woven fabric are provided so as to extend on both sides of the side edge of the fibrous layer, and each of the extended portions is folded so as to wrap around the side edge of the fibrous layer. The absorbent body according to claim 1, wherein side edges of the polymer layer and the hydrophilic nonwoven fabric are located on the upper surface side of the fibrous layer. In the absorbent article in which an absorbent body is interposed between the liquid-permeable top sheet and the back sheet,
An absorbent article using the absorbent according to any one of claims 1 to 9 as the absorbent.

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