阅读说明：本技术 吸收体及其制造方法以及吸收性物品 (Absorbent body, method for producing same, and absorbent article ) 是由 小山英俊 于 2019-02-01 设计创作，主要内容包括：本发明难以产生凝结阻滞,体液的吸收速度以及吸水能力能够提高,能够防止倒流,不会使佩戴感变差。本发明的吸收体(4)具备由纸浆纤维以及高吸水性聚合物构成的吸水性积纤体(8)、以及覆盖上述吸水性积纤体(8)的至少皮肤对置面的罩片(9)。在上述罩片(9)的非皮肤对置面形成有向外侧突出的多个凸部(10)和与上述凸部(10)邻接的凹陷的凹部(11),在上述凹部(11)积纤有上述吸水性积纤体(8)。上述吸水性积纤体(8)以使其厚度为与其邻接的上述凸部(10)的高度同等以下的方式设置。(The invention is difficult to generate coagulation retardation, can improve the absorption speed and water absorption capacity of body fluid, can prevent backflow, and can not make wearing feel worse. The absorbent body (4) of the present invention comprises a water-absorbing fiber-forming body (8) composed of pulp fibers and a super-absorbent polymer, and a cover sheet (9) covering at least the skin-facing surface of the water-absorbing fiber-forming body (8). A plurality of convex parts (10) protruding outward and concave parts (11) adjacent to the convex parts (10) are formed on the surface of the cover sheet (9) not facing the skin, and the water-absorbing integrated fiber body (8) is integrated in the concave parts (11). The water-absorbing integrated fiber (8) is provided so that the thickness thereof is equal to or less than the height of the adjacent convex portion (10).)

1. An absorbent body, comprising: a water-absorbing fiber-forming body composed of pulp fibers and a super-absorbent polymer; and a cover sheet covering at least the skin-facing surface of the water-absorbent fiber-reinforced body,

the absorbent body is characterized in that it is,

a plurality of convex portions protruding outward and concave portions adjacent to the convex portions are formed on the surface of the cover sheet not facing the skin, and the water-absorbing fiber-woven body is stacked in the concave portions.

2. An absorbent body according to claim 1,

the water-absorbing integrated fiber is provided so that the thickness thereof is equal to or less than the height of the convex portion adjacent to the water-absorbing integrated fiber.

3. Absorbent body according to any one of claims 1, 2,

a part of the superabsorbent polymer of the absorbent integrated body is embedded in the convex portion of the cover sheet.

4. The absorbent according to any one of claims 1 to 3,

the absorbent body has a ridge-and-groove structure in which the convex portions extend in the longitudinal direction of the cover sheet, a plurality of ridges are arranged at intervals in the short-side direction of the cover sheet, and the concave portions are grooves.

5. The absorbent according to any one of claims 1 to 4,

a second water-absorbing integrated fiber body having a pulp fiber blending ratio set to be higher than that of the water-absorbing integrated fiber body is disposed adjacent to the non-skin-facing surface side of the water-absorbing integrated fiber body,

at least the non-skin-facing surface of the second water-absorbent fiber-reinforced body is covered with a second cover sheet.

6. A method for producing an absorber according to any one of claims 1 to 5,

the method for producing an absorbent body is characterized in that,

a cover sheet having the convex portion and the concave portion formed on one surface thereof is prepared in advance, the cover sheet is supplied to a fiber stacking device having a fiber stacking concave portion with a predetermined shape on a peripheral surface thereof such that the surface on which the convex portion and the concave portion are formed faces an outer surface side, and the water-absorbing fiber stacking volume is stacked on the cover sheet in the fiber stacking concave portion.

7. The method for producing an absorbent body according to claim 6,

after the water-absorbing fiber-laminated volume is attached to the cover sheet in the fiber-laminated recess, the surface of the water-absorbing fiber-laminated body in the fiber-laminated recess is uniformly treated.

8. The method for manufacturing an absorbent body according to any one of claims 6 and 7,

in order to produce the method for producing the absorbent body according to claim 5,

in another step, the second water-absorbent integrated fiber is integrated by a second fiber integrating device having a second fiber integrating recess of a predetermined shape on the peripheral surface, and is placed on the second cover sheet to be supplied, and the water-absorbent integrated fiber integrated in the cover sheet is disposed adjacent to the second water-absorbent integrated fiber.

9. An absorbent article characterized in that,

the absorbent body according to any one of claims 1 to 5, which is disposed between a liquid-permeable top sheet covering the skin-facing surface side and a leakproof sheet covering the non-skin-facing surface side.

Technical Field

The present invention relates to an absorbent body which is used mainly for absorbent articles such as incontinence pads, disposable diapers, sanitary napkins, and panty liners and which does not cause retardation of coagulation even if the content of a super absorbent polymer is increased and has excellent liquid diffusion properties, a method for producing the absorbent body, and an absorbent article.

Background

Conventionally, as the absorbent article, there has been known an absorbent article in which an absorbent body made of cotton pulp, super absorbent polymer, or the like is interposed between a polyethylene sheet or a polyethylene sheet laminated with a leakproof sheet such as a nonwoven fabric or a liquid permeable surface sheet such as a nonwoven fabric or a liquid permeable plastic sheet.

As a method for producing the absorber, there is a method in which: a particle-packed body including a holding sheet and particles is obtained by continuously supplying the holding sheet in a belt shape to a packing apparatus including a particle suction unit, supplying the particles to the holding sheet in a scattered state, sucking the particles from the particle suction unit, and packing the particles on the holding sheet (see patent documents 1 and 2 below).

By adopting such a method for producing an absorbent body, the content of the super absorbent polymer can be increased, and an absorbent body having a high water absorption capacity can be continuously produced at a high speed in a thin shape with a reduced weight per unit area of pulp.

Patent document 1: japanese laid-open patent publication No. 2001-171029

Patent document 2: japanese patent laid-open No. 2008-507384

However, in the production methods described in patent documents 1 and 2, since the content of the super absorbent polymer is increased, in the case of repeated urination at intervals or the like, the voids between the polymer particles that have swollen by water absorption in the previous urination are extremely decreased, so-called "coagulation block" is likely to occur, and the desired water absorption capacity, liquid diffusibility, and absorption rate cannot be generated. As a result, the penetration of urine is inhibited by the binding between the polymer particles, and the urine prevented from penetrating flows back.

Further, if the content of the super absorbent polymer is increased, the super absorbent polymer is likely to move due to impact, pressure, or the like at the time of product conveyance or the like, and the moved super absorbent polymer is accumulated in the folded portion of the folded product. This causes problems such as a reduction in water absorption capacity and a reduction in wearing comfort, i.e., a highly localized increase in swelling due to water absorption.

Disclosure of Invention

Accordingly, a main object of the present invention is to provide an absorbent body, a method for producing the same, and an absorbent article, in which coagulation stagnation is less likely to occur, the absorption rate and water absorption capacity of body fluid can be improved, a reverse flow can be prevented, and the wearing feeling is not deteriorated.

In order to solve the above problem, the present invention according to claim 1 provides an absorbent body comprising: a water-absorbing fiber-forming body composed of pulp fibers and a super-absorbent polymer; and a cover sheet covering at least the skin-facing surface of the water-absorbent fiber-reinforced body,

the absorbent body is characterized in that a plurality of convex portions protruding outward and concave portions adjacent to the convex portions are formed on the surface of the cover sheet not facing the skin, and the absorbent integrated body is integrated into the concave portions.

In the invention described in claim 1, since the cover sheet has a structure in which the water-absorbing integrated fiber is integrated in the concave portion of the cover sheet in which the convex portion and the concave portion are formed, the body fluid can be reliably absorbed in the concave portion of the cover sheet in which the water-absorbing integrated fiber is disposed, and the liquid permeability of the body fluid passing through the cover sheet in the thickness direction is ensured by the convex portion in which the water-absorbing integrated fiber is not substantially disposed. Thus, even if the content of the super absorbent polymer is increased, the liquid permeability is ensured by the convex portions of the cover sheet, and therefore, it is difficult to cause a liquid passage failure due to the coagulation-blocking lock of the super absorbent polymer, and the absorption rate and water absorption capacity of the body fluid can be increased.

Further, since the water-absorbent fiber-reinforced polymer is disposed in the concave portion defined by the convex portion of the cover sheet, the super-absorbent polymer is less likely to move, and the super-absorbent polymer can be maintained in a uniformly dispersed state, thereby preventing the reduction in water absorption capacity and wearing comfort due to the displacement of the polymer.

The present invention according to claim 2 provides, in addition to the absorbent body according to claim 1, an absorbent body in which the water-absorbent integrated fibers are provided so that the thickness thereof is equal to or less than the height of the protrusions adjacent to the water-absorbent integrated fibers.

In the invention described in claim 2, since the water-absorbent integrated fiber is provided in such a thickness that the thickness thereof is equal to or less than the height of the convex portion adjacent to the water-absorbent integrated fiber, the body fluid can move to the lower layer side than the water-absorbent integrated fiber through the convex portion of the cover sheet. Further, by disposing a member having excellent diffusion properties in the plane direction adjacent to the lower layer side of the water-absorbent integrated fiber, for example, a member having a larger mixing ratio of pulp fibers than the water-absorbent integrated fiber, the body fluid is rapidly diffused in the member, and the body fluid is rapidly absorbed in the member or the water-absorbent integrated fiber adjacent to the upper layer side of the member.

The present invention according to claim 3 provides the absorbent core according to any one of claims 1 and 2, wherein a part of the superabsorbent polymer of the absorbent core is embedded in the convex portion of the cover sheet.

In the invention described in claim 3, when the water-absorbent integrated fiber body is stacked, a treatment of sucking on a fiber stacking drum, a treatment of making the water-absorbent integrated fiber body uniform on the surface of the cover sheet on which the convex portions and the concave portions are formed, and then a gluing roller, or the like is performed, whereby a part of the highly water-absorbent polymer constituting the water-absorbent integrated fiber body is embedded in the convex portions of the cover sheet. Thus, the convex portion of the cover sheet can also exert a water absorbing function, and the amount of body fluid absorbed can be further increased.

The present invention according to claim 4 provides an absorbent body having a ridge-and-groove structure in addition to the absorbent body according to any one of claims 1 to 3, wherein the convex portions are ridges extending in the longitudinal direction of the cover sheet and arranged at intervals in the short-side direction of the cover sheet, and the concave portions are grooves.

In the invention according to claim 4, since the surface of the cover sheet facing the water-absorbent integrated fibers has a ridge-and-groove structure, the water-absorbent integrated fibers are easily arranged along the grooves, and the water-absorbent integrated fibers arranged in the grooves are less likely to move, so that the water-absorbent integrated fibers are more firmly fixed. Further, since the convex portion serving as the ridge does not substantially contain a polymer, the convex portion functions as a slit, and body fluid is easily diffused in the direction in which the ridge extends.

The present invention according to claim 5 provides the absorbent body according to any one of claims 1 to 4, further comprising a second water-absorbent integrated fiber body having pulp fibers disposed adjacent to the non-skin-facing surface side of the water-absorbent integrated fiber body at a blending ratio greater than that of the pulp fibers of the water-absorbent integrated fiber body, wherein at least the non-skin-facing surface of the second water-absorbent integrated fiber body is covered with a second cover sheet.

In the invention according to claim 5, since the second water-absorbent integrated fiber in which the proportion of pulp fibers is set to be larger than the proportion of pulp fibers in the water-absorbent integrated fiber is disposed adjacent to the non-skin-facing surface side of the water-absorbent integrated fiber, the body fluid that has moved to the lower layer side of the water-absorbent integrated fiber by the convex portion of the cover sheet can be diffused over a wide range in the second water-absorbent integrated fiber, and the fluid passage failure due to the coagulation inhibition of the water-absorbent integrated fiber can be more reliably prevented, and the absorption rate and water absorption capacity of the body fluid can be further improved.

The present invention according to claim 6 provides a method for producing an absorbent body according to any one of claims 1 to 5, wherein a cover sheet having the convex portions and the concave portions formed on one surface thereof is prepared in advance, the cover sheet is supplied to a fiber stacking device having a fiber stacking concave portion with a predetermined shape on a peripheral surface thereof such that the surface on which the convex portions and the concave portions are formed faces an outer surface side, and the water-absorbent fiber stacking volume is formed on the cover sheet in the fiber stacking concave portion.

In the invention described in claim 6, since the cover sheet in which the convex portions and the concave portions are formed in advance is supplied to the fiber stacking device such that the surface in which the convex portions and the concave portions are formed faces the outer surface side, and the water-absorbing integrated fibers are stacked on the cover sheet in the fiber stacking concave portions, the water-absorbing integrated fibers can be easily stacked on the concave portions of the cover sheet.

The present invention according to claim 7 provides, in addition to the method for producing an absorbent body according to claim 6, a method for producing an absorbent body, in which the water-absorbing fiber-laminated bulk fibers are placed on the cover sheet in the fiber-laminated depressions, and then the surfaces of the water-absorbing fiber-laminated bulk fibers in the fiber-laminated depressions are uniformly treated.

In the invention according to claim 7, after the water-absorbent fiber-laminated volume fibers are placed on the cover sheet in the fiber-laminated concave portions, the surfaces of the water-absorbent fiber-laminated bodies in the fiber-laminated concave portions are uniformly treated with a glue roll or the like, whereby the water-absorbent fiber-laminated bodies can be reliably fixed in the concave portions, and a part of the highly water-absorbent polymer is embedded in the convex portions, and the fiber-laminated height of the water-absorbent fiber-laminated bodies can be made equal to or less than the height of the convex portions.

The present invention according to claim 8 provides, in addition to the method of manufacturing an absorbent body according to any one of claims 6 and 7, a method of manufacturing an absorbent body according to claim 5, wherein in a separate step, the second water-absorbent integrated fibers are integrated by a second fiber integration device having a second fiber integration concave portion of a predetermined shape on a peripheral surface, and the second water-absorbent integrated fibers are placed on the second cover sheet to be supplied, and the water-absorbent integrated fibers integrated with the cover sheet are arranged adjacent to the second water-absorbent integrated fibers.

The invention described in claim 8 is a method for producing an absorbent body in which a second water-absorbent integrated body and a second cover sheet are laminated in this order adjacent to the non-skin-facing surface side of the water-absorbent integrated body. In this case, in another step, a member is produced in which a second water-absorbent fiber laminate is placed on the second cover sheet, and the water-absorbent fiber laminate is arranged on the cover sheet so as to be adjacent to the upper surface of the second water-absorbent fiber laminate.

The present invention according to claim 9 provides an absorbent article wherein the absorbent body according to any one of claims 1 to 5 is disposed between a liquid-permeable top sheet covering a skin-facing surface side and a leakproof sheet covering a non-skin-facing surface side.

ADVANTAGEOUS EFFECTS OF INVENTION

As described above in detail, according to the present invention, it is possible to provide an absorbent body, a method for manufacturing the same, and an absorbent article, in which coagulation stagnation is less likely to occur, the absorption rate and water absorption capacity of body fluid can be improved, and a reverse flow can be prevented without deteriorating a wearing feeling.

Drawings

Fig. 1 is a partially cut-away, expanded view of an incontinence pad 1 of the invention.

Fig. 2 is a line-up view II-II of fig. 1.

Fig. 3 is a view in line III-III of fig. 1.

Fig. 4 is a plan view of a laminate of the water-absorbent fiber body 8 and the cover sheet 9 as viewed from the non-skin-facing surface side.

Fig. 5 is a view along the V-V line of fig. 4.

Fig. 6 is a cross-sectional view of the absorbent body 4 showing the absorption path of bodily fluid.

Fig. 7 is a vertical sectional view showing the manufacturing apparatuses 30 and 40 of the absorbent body 4.

Fig. 8 is a longitudinal sectional view showing the manufacturing apparatus 30.

Detailed Description

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

Example of basic construction of an incontinence pad

As shown in fig. 1 to 3, the incontinence pad 1 of the present invention is mainly composed of a leakproof sheet 2, a surface sheet 3, an absorbent body 4, an outer sheet 5 and side nonwoven fabrics 6, wherein the leakproof sheet 2 is composed of a polyethylene sheet or the like, the surface sheet 3 serves as a skin contact surface to allow urine or the like to rapidly pass therethrough, the absorbent body 4 is interposed between the two sheets 2, 3, the outer sheet 5 covers the outermost surface (non-skin contact surface) of the incontinence pad 1, the side nonwoven fabrics 6, 6 have substantially side edge portions of the absorbent body 4 as upright base ends and form a pair of left and right three-dimensional gathers BS, BS projecting toward the skin side in a predetermined section including at least the urination opening portion of the wearer in the front-rear direction, and outer edge portions of the leakproof sheet 2, the surface sheet 3 and the outer sheet 5 are joined to each other at the upper and lower edge portions around the absorbent body 4 by a joining means such as an adhesive such as a hot melt adhesive, heat sealing, ultrasonic sealing, the leakproof sheet 2, the topsheet 3, the outer sheet 5 and the side nonwoven fabric 6, which extend laterally beyond the absorbent body 4, are joined to both side edges of the absorbent body 4 by joining means such as an adhesive such as a hot melt adhesive, heat sealing or ultrasonic sealing.

Although a sheet having at least water-barrier properties such as polyethylene can be used for the leakproof sheet 2, a sheet having moisture-permeability is used in recent years in view of prevention of stuffy wetting. As the water-barrier moisture-permeable sheet, a microporous sheet obtained by melt-kneading an inorganic filler in an olefin resin such as polyethylene or polypropylene to form a sheet and then stretching the sheet in a uniaxial or biaxial direction is preferably used. As the leakproof sheet 2, a laminated nonwoven fabric in which a plastic film and a nonwoven fabric are laminated may be used.

Next, for the top sheet 3, a porous or nonporous nonwoven fabric, a porous plastic sheet, or the like is preferably used. As the raw material fibers constituting the nonwoven fabric, in addition to synthetic fibers such as olefin-based fibers such as polyethylene or polypropylene, polyester-based fibers, and polyamide-based fibers, regenerated fibers such as rayon and cuprammonium, and natural fibers such as cotton, nonwoven fabrics obtained by an appropriate processing method such as spunlace, spunbond, thermal bond, melt blowing, and needle punching can be used. Among these processing methods, the spunlace method is advantageous in that it is rich in flexibility and drapability, and the thermal bonding method is advantageous in that it is bulky and has high compression recovery. When the surface sheet 3 is formed with a plurality of through holes, body fluid can be absorbed quickly, and the dry touch property is excellent. The fibers of the nonwoven fabric may be either long fibers or short fibers, but short fibers are preferably used in order to produce a toweling texture. In addition, for easy embossing, olefin fibers such as polyethylene or polypropylene having a relatively low melting point can be used. Further, a composite fiber of a core-sheath fiber, a side-by-side fiber, and a split fiber, in which a fiber having a high melting point is used as a core and a fiber having a low melting point is used as a sheath, can be suitably used.

The outer sheet 5 covers the leakproof sheet 2 to give the outer surface of the incontinence pad 1 a cloth-like appearance and a skin touch. The exterior sheet 5 is preferably formed of a nonwoven fabric. As the raw material fiber, besides synthetic fibers such as olefin-based fibers such as polyethylene or polypropylene, polyester-based fibers, and polyamide-based fibers, regenerated fibers such as rayon and cuprammonium, and natural fibers such as cotton can be used, and the fiber can be produced by a spunlace method, a spunbond method, a thermal bond method, an air flow method, a needle punch method, and the like. However, long fiber nonwoven fabrics such as spunbond nonwoven fabrics, SMS nonwoven fabrics, SMMS nonwoven fabrics and the like are preferable in terms of achieving both the skin touch feeling and the strength.

In addition to one nonwoven fabric, a plurality of nonwoven fabrics may be used in a superposed manner, and when a plurality of nonwoven fabrics are used in a superposed manner, the nonwoven fabrics are preferably fixed to each other via an adhesive such as a hot melt adhesive. When a nonwoven fabric is used, the nonwoven fabric preferably has a fiber basis weight of 10 to 50g/m²Particularly preferably 15 to 30g/m²。

One or more stopper layers (not shown) may be formed on the non-use surface side (outer surface) of the outer sheet 5, and the incontinence pad 1 may be fixed to underwear, a disposable diaper, or the like when worn on the body. As the stopper layer, a hook member of mechanical engagement type may be used, or an adhesive may be used. The stopper layer may be provided or not provided as needed.

In the illustrated example, the outer sheet 5 is wideThe degree of the side nonwoven fabric 6 is slightly larger than the width of the absorbent body 4, and the side nonwoven fabric 6 extending from the surface of the side portion of the topsheet 3 is disposed on the outer surface side of the topsheet 3 extending toward the skin side of the outer sheet 5 on the outer side in the width direction of the topsheet 3 so as to wind the side edges of the barrier sheet 2 and the topsheet 3, and specifically, the side nonwoven fabric 6 is formed using a nonwoven fabric material subjected to an appropriate water repellent treatment or hydrophilic treatment for the purpose of preventing permeation of urine or the like or improving the skin touch. As the side nonwoven fabric 6, a nonwoven fabric formed from natural fibers, synthetic fibers, regenerated fibers or the like as a raw material by an appropriate processing method can be used, but in order to eliminate stiffness and prevent stuffiness, a nonwoven fabric having air permeability while suppressing the weight per square meter is preferably used. Specifically, the amount of the organic solvent is preferably 13 to 23g/m per square meter²For the nonwoven fabric produced, a water repellent treated nonwoven fabric coated with a water repellent such as a silicon based, paraffin based, or alkyl chromium chloride based is preferably used in order to reliably prevent the permeation of body fluid.

The inner portion of the side nonwoven fabric 6 is folded back approximately in two folds, and linear elastic members 7 and 7 … having both ends or suitable positions in the longitudinal direction fixed are disposed in the middle portion in the height direction in the double sheet, and one or more, in the illustrated example three, linear elastic members 7 and 7 … are disposed, and both ends or suitable positions in the longitudinal direction of the linear elastic members 7 and 7 … are fixed. As shown in fig. 3, the double-sheet portion is folded back once outward at the front and rear end portions and bonded to the absorbent body 4 side in a laminated state, and as shown in fig. 2, three-dimensional gathers BS, BS standing up to the skin side are formed in pairs in the left and right in a predetermined section in the front-rear direction including at least the urination opening portion of the wearer.

< absorbent body >

The absorber 4 interposed between the leakproof sheet 2 and the surface sheet 3 includes: a water-absorbing fiber-forming body 8 made of pulp fibers and a super water-absorbing polymer; and a cover sheet 9 covering at least the skin-facing surface of the water-absorbent fiber-reinforced body 8, wherein the absorbent body 4 has a property of absorbing and retaining body fluid.

The water-absorbent fiber-reinforced body 8 is composed of, for example, cotton pulp and a super absorbent polymer. The super absorbent polymer is mixed as, for example, granular powder into the pulp constituting the water-absorbent fiber-forming body 8. The pulp includes pulp made of cellulose fibers such as chemical pulp made of wood and dissolving pulp, and artificial cellulose fibers such as rayon and acetate, and softwood pulp having a longer fiber length is preferably used in terms of function and price than hardwood pulp.

Further, synthetic fibers may be mixed in the water-absorbent fiber assembly 8. Examples of the synthetic fibers include polyolefin fibers such as polyethylene and polypropylene, polyester fibers such as polyethylene terephthalate and polybutylene terephthalate, polyamide fibers such as nylon, and copolymers thereof, and a mixture of these two types of fibers may be used. Further, composite fibers such as core-sheath fibers, side-by-side fibers, and split fibers, in which a fiber having a high melting point is used as a core and a fiber having a low melting point is used as a sheath, can also be used. In the case where the synthetic fibers are hydrophobic fibers, it is preferable to use fibers that have been surface-treated with a hydrophilizing agent so as to have affinity for body fluids.

The super absorbent polymer includes "powder" in addition to "particles". The superabsorbent polymer can be used as it is in the particle size used in the absorbent article, and has an average particle size of 1000 μm or less, preferably 99% or more by weight of the superabsorbent polymer having a particle size of 106 μm or more in the unabsorbed state, and particularly preferably 99% or more by weight of the superabsorbent polymer having a particle size of 150 to 850 μm. The average particle diameter is preferably about 250 to 500 μm when not absorbed. In addition, the average particle diameter of the super absorbent polymer after absorption is preferably three times or more, more specifically, 500 μm or more, as large as the average particle diameter of the super absorbent polymer before absorption. The average particle diameter of the super absorbent polymer when not absorbed means a particle diameter having an integrated value of 50% in the weight-based particle size distribution. In this case, the weight-based particle size distribution was determined in accordance with JIS Z8815-1994. Specifically, screens having meshes of 710 μm, 500 μm, 300 μm, 150 μm and 106 μm with an inner diameter of 150mm and a depth of 45mm were superposed on each other with a narrow mesh screen placed therebelow, 50g of a measurement sample was placed on the 710 μm screen having the widest mesh screen on the uppermost screen, the screen was screened for 10 minutes by a screen shaker, the weight of the measurement sample remaining on each screen was measured, and the percentage of the weight of the measurement sample remaining on each screen to the weight of the initial measurement sample was determined.

The basis weight of the super absorbent polymer can be determined appropriately according to the absorption amount required for the use of the absorbent body 4. Therefore, it can be 50 to 350g/m². If the weight per unit area of the polymer is less than 50g/m²It is difficult to ensure the absorption amount. If it exceeds 350g/m²The effect is not only saturated but also gives a sense of discomfort to the presence of particles due to the excess of the super absorbent polymer.

The water-absorbing fiber 8 preferably has a ratio of the weight of the super-absorbent polymer to the total weight of the pulp and the super-absorbent polymer of 50 to 90%. As described in detail later, since the water-absorbent fiber-reinforced polymer 8 is disposed in a predetermined region of the cover sheet 9, if the weight ratio of the super-absorbent polymer is less than 50%, the water absorption capacity may be insufficient. On the other hand, if the weight ratio is greater than 90%, the particulate (particulate) feel of the super absorbent polymer is strongly felt, and the feeling of use is reduced.

The cover sheet 9 is made of thin paper, and in particular, is made of crepe paper, nonwoven fabric, laminated nonwoven fabric, a sheet with small holes, or the like. However, a sheet that does not exude the super absorbent polymer is preferable. When a nonwoven fabric is used instead of the crepe paper, a bulky structure is easily adopted, and a hot air nonwoven fabric having excellent suitability for embossing is particularly preferable. In order to facilitate formation of the irregularities described later, the fiber basis weight is preferably 15g/m²Above, particularly preferably 20 to 100g/m²。

As shown in fig. 4 and 5, a plurality of convex portions 10 protruding outward (non-skin side) and concave portions 11 adjacent to the convex portions 10 are formed on the non-skin-facing surface of the cover sheet 9. That is, only the surface (non-skin-facing surface) of the cover sheet 9 opposite to the surface facing the wearer's skin surface when the incontinence pad 1 is worn is formed with the projections 10 and the recesses 11 having different heights in the thickness direction, and the surface (skin-facing surface) opposite thereto is a flat surface.

As shown in fig. 4, the convex portion 10 is preferably provided in an intermediate portion that does not reach the outer edge of the absorbent body 4, and thus a concave portion 11 is preferably formed in the outer edge. In the plan view shown in fig. 4, the area occupied by the projections 10 may be 50% or less, preferably 10 to 35% of the area of the absorbent body 4 (the total area of the projections 10 and the recesses 11). In the following description, since the water-absorbing fiber aggregate 8 is disposed in the concave portion 11, if the area of the convex portion 10 is too large, the water absorption capacity may be lowered.

The cover sheet 9 extends to substantially the outer edge of the absorbent member 4, and the water-absorbent integrated fibers 8 are arranged in a predetermined area with a predetermined thickness, so that the cover sheet 9 and the water-absorbent integrated fibers 8 constitute an integrated laminate.

In the surface formed with the irregularities, the water-absorbing integrated fibers 8 are integrated in the concave portions 11. Preferably, the water-absorbent fiber-reinforced body 8 is formed by stacking fibers in the concave portion 11 of the cover sheet 9 and hardly stacked in the convex portion 10. The term "not to be stacked on the convex portions 10" means that the pulp fibers and the super absorbent polymer constituting the water-absorbent stacked body 8 are substantially absent on the convex portions 10, the pulp fibers and the super absorbent polymer are not present at all, or the pulp fibers and the super absorbent polymer are slightly present by suction treatment at the time of stacking, treatment for making the surface uniform by using a glue roll or the like, but the amount thereof is extremely smaller than that of the concave portions 11.

The water-absorbing integrated fibers 8 are preferably provided so that the thickness thereof is equal to or less than the height of the adjacent protrusions 10. That is, the water-absorbent fiber-reinforced body 8 may be formed to have a height substantially equal to or lower than the height of the protrusions 10 with respect to the fibers stacked in the recesses 11.

As shown in fig. 2 and 6, the absorbent body 4 is preferably configured such that: a second water-absorbent integrated body 12 made of pulp fibers and a super-absorbent polymer is disposed adjacent to the non-skin-facing surface side of the water-absorbent integrated body 8, and at least the non-skin-facing surface of the second water-absorbent integrated body 12 is covered with a second cover sheet 13. In this case, it is preferable that the second water-absorbent integrated body 12 is set to have a larger blending ratio of pulp fibers and a smaller blending ratio of the super-absorbent polymer than the water-absorbent integrated body 8. Specifically, the weight ratio of the pulp fibers to the total weight of the pulp and the super absorbent polymer is 50 to 90%, and preferably 60 to 90%. By thus containing a large amount of pulp fibers in the second water-absorbent integrated fibers 12, rapid diffusion in the planar direction by capillary action is likely to occur when absorbing body fluid.

The second water-absorbent integrated body 12 is formed in a planar shape substantially equivalent to the laminate of the cover sheet 9 and the water-absorbent integrated body 8.

The second cover sheet 13 may be formed of a thin paper, in particular, a crepe paper, a nonwoven fabric, a laminated nonwoven fabric, a sheet with small holes, or the like, as in the cover sheet 9. However, a sheet that does not exude the super absorbent polymer is preferable. When a nonwoven fabric is used instead of the crepe paper, a hydrophilic SMMS (spunbond/meltblown/spunbond) nonwoven fabric is particularly preferable, and polypropylene, polyethylene/polypropylene, or the like can be used as a material thereof. The preferred fiber weight per unit area is 5-40 g/m²Particularly preferably 10 to 30g/m²。

The second cover sheet 13 is substantially equal to or slightly longer than the laminated body of the cover sheet 9 and the water-absorbent integrated fiber 8 in the length direction of the pad, and is laminated in a size substantially equal to both ends of the laminated body, or slightly longer than the laminated body in the length direction. On the other hand, as shown in fig. 2, the pad is provided so as to extend further to both sides than the laminate of the cover sheet 9 and the water-absorbent integrated body 8 in the pad width direction, and is folded on both side portions of the skin-facing surface side of the cover sheet 9 so as to wrap the side edges of the laminate and the second water-absorbent integrated body 12. Thus, both side edges of the absorbent body 4 are covered with the second cover sheet 13, and therefore, the structure is less likely to cause side leakage.

In this way, since the structure is provided in which the water-absorbent integrated fibers 8 are integrated in the concave portions 11 of the cover sheet 9 in which the convex portions 10 and the concave portions 11 are formed, as shown in fig. 6, the body fluid can be reliably absorbed by the concave portions 11 of the cover sheet 9 in which the water-absorbent integrated fibers 8 are arranged, and the liquid permeability of the body fluid passing through the cover sheet 9 in the thickness direction can be ensured by the convex portions 10 in which the water-absorbent integrated fibers 8 are hardly arranged. Thus, since the water-absorbent fiber assembly 8 ensures liquid permeability by the convex portions 10 of the cover sheet 9, even if the content of the super absorbent polymer is increased, the liquid permeability is hardly impaired by the coagulation inhibition of the super absorbent polymer, the absorption rate and water absorption capacity of the body fluid can be increased, and the body fluid hardly remains on the front surface side, so that the back flow of the body fluid can be prevented.

Further, since the water-absorbent fiber 8 is disposed in the concave portion 11 defined by the convex portion 10 of the cover sheet 9, the super-absorbent polymer is less likely to move, and the state in which the super-absorbent polymer is uniformly dispersed and disposed can be maintained, and the reduction in water absorption capacity due to the deviation of the polymer and the deterioration in wearing feeling can be prevented.

Further, since the water-absorbent integrated fibers 8 are provided so that the thickness thereof is equal to or less than the height of the adjacent projections 10, the body fluid easily moves to the second water-absorbent integrated fibers 12 disposed on the lower layer side of the water-absorbent integrated fibers 8 through the projections 10 of the cover sheet 9.

Further, as shown in fig. 6, since the second water-absorbent integrated body 12 excellent in the diffusion property in the plane direction is disposed adjacent to the lower layer side of the water-absorbent integrated body 8, the body fluid rapidly diffuses inside the second water-absorbent integrated body 12, and the body fluid is rapidly absorbed into the member of the second water-absorbent integrated body 12 or the water-absorbent integrated body 8 adjacent to the upper layer side of the second water-absorbent integrated body 12.

The convex portions 10 and the concave portions 11 may be arranged in any pattern. The arrangement pattern of fig. 4 and 5 has a ridge-and-groove structure, the convex portion 10 is formed by extending in the longitudinal direction of the cover sheet 9 and a plurality of ridges are arranged with a space in the short-side direction, and the concave portion 11 is formed as a groove. Since the cover sheet 9 has the ridge-and-groove structure, the water-absorbent fiber-reinforced polymer 8 can be easily arranged along the groove, and the water-absorbent fiber-reinforced polymer 8 arranged in the groove is less likely to move, so that the water-absorbent fiber-reinforced polymer 8 can be fixed well. Further, since the convex portions 10 which become ridges do not substantially contain a super absorbent polymer or contain a small amount of super absorbent polymer, the function of slits which do not contain a super absorbent polymer is exhibited, and body fluid is easily diffused in the direction in which the ridges extend. Although the ridge groove structure is formed in a straight line in the longitudinal direction at substantially equal intervals in the width direction of the absorbent body 4, the interval between the adjacent projections 10, 10 may be arranged in a radial shape that is narrowest at the urination opening and gradually widens toward the front and rear in order to improve the liquid permeability at the urination opening.

In the example shown in fig. 5, the upper surface (non-skin-facing surface) of the projection 10 is formed to be substantially flat, but more preferably, it is formed to be a curved surface bulging toward the non-skin side as viewed in a cross section of the absorbent body 4 shown in fig. 7. By forming the top of the convex portion 10 as a curved surface bulging outward, the convex portion 10 is likely to protrude further outward than the water-absorbent integrated fiber 8 stacked in the concave portion 11 and to come into contact with the second water-absorbent integrated fiber 12 on the lower layer side, and therefore, the body fluid on the skin side is likely to move to the second water-absorbent integrated fiber 12 through the convex portion 10.

< method for producing absorbent body >

Next, a method for producing the absorbent body 4 will be described. The cover piece 9 having the convex portion 10 and the concave portion 11 on one side surface is prepared in advance. A known method can be used for producing the convex portion 10 and the concave portion 11. For example, in the case of a nonwoven fabric having a flat surface, unevenness may be provided by embossing a portion corresponding to the recessed portion 11, or unevenness may be provided by blowing a fluid to a portion corresponding to the recessed portion 11 and gathering fibers of the recessed portion 11 to the protruding portion 10 in the nonwoven fabric manufacturing step of the cover sheet 9.

Next, a laminate of the cover sheet 9 and the water-absorbent integrated fibers 8 was produced. The laminate is produced by, for example, the first production apparatus 30 shown in fig. 8. The first manufacturing apparatus 30 includes a defibering apparatus 31 for finely pulverizing a supplied fibrous sheet material constituting the water-absorbent fiber-laminated body 8, a pulverized pulp supply casing 32 for surrounding the defibering apparatus 31 and conveying pulverized pulp by an air flow, and a fiber-laminating apparatus 33 disposed at a downstream opening of the pulverized pulp supply casing 32. The fiber accumulating device 33 is constituted by a fiber accumulating rotary drum 35 and a suction chamber 36, wherein the fiber accumulating rotary drum 35 is provided with fiber accumulating recesses 34 and 34 … at an outer peripheral surface at an appropriate interval, a plurality of suction holes (not shown) are provided in a bottom surface of the fiber accumulating recess 34, the suction chamber 36 is disposed inside the fiber accumulating rotary drum 35, and the inside of the suction chamber 36 is maintained at a negative pressure by a suction means (not shown), whereby the absorbent body constituting fibers transported into the fiber accumulating recess 34 by air are accumulated. The crushed pulp supply casing 32 is provided with a polymer inlet 37 for supplying the pulverized pulp together with the particulate matter of the super absorbent polymer.

In order to produce a laminated body of the cover sheet 9 and the water-absorbent integrated fiber body 8 by the first production apparatus 30, the cover sheet 9 on which the convex portions 10 and the concave portions 11 are formed is supplied to the fiber stacking apparatus 33 such that the convex and concave forming surfaces face the outer surface side, the cover sheet 9 is held by the fiber stacking rotating drum 35 of the fiber stacking apparatus 33, and the fibers to be defibrated by the defibering apparatus 31 are stacked on the cover sheet 9 in the fiber stacking concave portions 34.

In the fibers of the water-absorbent fiber-laminated body 8, the particulate matter of the super-absorbent polymer supplied together with the crushed pulp is embedded in the convex portion 10 and the concave portion 11 of the cover sheet 9 by suction from the bottom surface of the fiber-laminated concave portion 34. Accordingly, the projections 10 can exhibit water absorption capacity, and the body fluid permeating the cover sheet 9 through the projections 10 is also absorbed and held by the super absorbent polymer.

The fibers deposited on the convex portions 10 fall into the concave portions 11 by the gluing roller 38, and the water-absorbent fiber-laminated bodies 8 deposited at a height equal to or higher than the height of the convex portions 10 are averaged to the height of the convex portions 10 as a whole. At this time, the excess water-absorbent integrated fibers 8 are scraped off by the gluing roller 38.

On the other hand, a laminate of the second water-absorbent integrated body 12 and the second cover sheet 13 is produced by a second production apparatus 40 shown in fig. 8. As the second manufacturing apparatus 40, a normal fiber stacking apparatus can be used. The second manufacturing apparatus 40 includes a defibering apparatus 41 for finely pulverizing a supplied fibrous sheet material constituting the second water-absorbent integrated body 12, a pulverized pulp supply casing 42 for surrounding the defibering apparatus 41 and conveying the pulverized pulp by an air flow, and a fiber deposition apparatus 43 disposed at a downstream opening of the pulverized pulp supply casing 42. The fiber accumulating device 43 is constituted by a fiber accumulating rotary drum 45 and a suction chamber 46, wherein the fiber accumulating rotary drum 45 is provided with fiber accumulating recesses 44 at an outer peripheral surface at appropriate intervals, a plurality of suction holes (not shown) are provided in a bottom surface of the fiber accumulating recesses 44, the suction chamber 46 is disposed inside the fiber accumulating rotary drum 45, and the suction chamber 46 is maintained at a negative pressure by a suction means (not shown), whereby the absorbent body constituting fibers transported into the fiber accumulating recesses 44 by air are accumulated. The crushed pulp supply casing 42 is provided with a polymer inlet 47 for supplying the pulverized pulp together with the particulate matter of the super absorbent polymer. Further, a gluing roller 48 may be provided, and the gluing roller 48 may scrape off the second water-absorbent integrated fibers 12 that have filled the excess accumulated in the fiber-stacking recess 44.

In order to produce a laminate of the second water-absorbent integrated fiber 12 and the second cover sheet 13 by the second production apparatus 40, the second water-absorbent integrated fiber 12 is produced by the fiber-separating apparatus 41 separating the fibers, and then the fibers are collected by the fiber-collecting apparatus 43, and the second water-absorbent integrated fiber 12 is transferred to the second cover sheet 13 serving as a holding sheet transferred by the conveyor belt 50.

The second water-absorbent integrated fiber 12 transferred to the second cover sheet 13 is transferred to the first manufacturing apparatus 30 by the conveyor 50, and the laminate of the cover sheet 9 and the water-absorbent integrated fiber 8 manufactured by the first manufacturing apparatus 30 is placed, whereby the absorbent body 4 is completed.

Description of reference numerals:

1 … incontinence pad; 2 … leakproof sheet; 3 … surface sheet; 4 … absorbent body; 5 … external sheet; 6 … side nonwoven; 7 … linear elastic expansion member; 8 … A water-absorbent, fiber-forming body; 9 … cover sheet; 10 … protrusions; 11 … recess; 12 … a second water-absorbent fiber-forming body; 13 … second cover sheet; 30 … a first manufacturing device; 31. 41 … defibering device; 32. 42 … crushing the pulp supply casing; 33. 43 … fiber stacking device; 34. 44 … recessed part for fiber accumulation; 35. 45 … rotary drum for fiber accumulation; 36. 46 … suction chamber; 37. 47 … Polymer dosing port; 38. 48 … gluing rollers; 50 … conveyor belt.