JP2007222265A - Absorbent article - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an absorbent article scarcely lowering the absorption speed of liquid with the body pressure of a wearer applied thereon. <P>SOLUTION: This absorbent article is provided with an absorbent body 10 including fibrous materials 20 and 23, and particles of superabsorbent polymer 21. The absorbent body 10 further includes a pressure mitigation material 22 composed of hydrophobic and non-water-absorbing material. The pressure mitigation material 22 has a diameter larger than the grain size of a particle of the saturated and swelled superabsorbent polymer 21 under load of 2kPa. The fibrous materials included in the absorbent body 10 are composed of web or pulp of filaments. Preferably, this absorbent article includes the pressure mitigation material 22 of 0.2-2 times of the weight of the particles of superabsorbent polymer 21. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to absorbent articles such as disposable diapers, sanitary napkins, and incontinence pads.

  It has been proposed that an absorbent body of an absorbent article contains large surface area open-cell hydrophilic polymer foam particles (see Patent Document 1). The foam particles have a dry particle size of less than 1000 μm. In addition, the foam particles absorb liquid by capillary attraction due to having open cells.

  However, as shown in FIG. 7, in this absorbent article, since the foam particles 122 contained in the absorbent body 100 are hydrophilic and have water absorption properties, they absorb the liquid excreted by themselves and are flat. The liquid tends to diffuse in the direction. As a result, it is difficult for the liquid to permeate in the thickness direction of the absorbent body 100, and the liquid absorption speed becomes slow. Moreover, as shown in the figure, since the liquid diffuses in the plane direction on the skin facing surface side of the absorbent body 100, the liquid easily evaporates, and the inside of the dressing is easily stuffy. In the figure, reference numeral 121 denotes a superabsorbent polymer particle, and 123 denotes pulp.

Japanese translation of PCT publication No. 2002-506689

  Therefore, the objective of this invention is providing the absorbent article which can eliminate the fault which the prior art mentioned above has.

The present invention is an absorbent article comprising an absorbent body comprising fibrous material and superabsorbent polymer particles,
The absorber further includes a pressure relaxation material made of a hydrophobic non-water-absorbing material,
The said pressure relaxation material achieves the said objective by providing the absorbent article whose diameter is larger than the particle diameter under the load of 2 kPa of the particle | grains of the said superabsorbent polymer which carried out saturation swelling.

  According to the absorbent article of the present invention, the diffusion of the liquid in the plane direction is suppressed, the diffusion of the liquid in the thickness direction is promoted, the liquid absorption rate is improved, and the liquid remains on the skin facing surface side of the absorbent body. It becomes difficult. As a result, the inside of the dress is less likely to be stuffy, and skin irritation is less likely to occur. In particular, according to the absorbent article of the present invention, the liquid absorption rate is difficult to decrease not only when the wearer's body pressure is not applied but also when the body pressure is applied.

  Hereinafter, the present invention will be described based on preferred embodiments thereof. The absorbent article of the present invention is mainly used for absorbing and holding excretory body fluids such as urine and menstrual blood. The absorbent article of the present invention includes, for example, disposable diapers, sanitary napkins, incontinence pads, etc., but is not limited thereto, and widely includes articles used for absorbing liquid discharged from the human body. .

  The absorbent article of the present invention typically includes a top sheet, a back sheet, and a liquid-retaining absorbent body disposed between both sheets. As the top sheet and the back sheet, materials usually used in the technical field can be used without particular limitation. For example, as the surface sheet, liquid permeable sheets such as various nonwoven fabrics and perforated films subjected to a hydrophilic treatment can be used. As the back sheet, a liquid-permeable or water-repellent sheet such as a thermoplastic resin film or a laminate of the film and a nonwoven fabric can be used. The back sheet may have water vapor permeability. The absorbent article may further include various members according to specific uses of the absorbent article. Such members are known to those skilled in the art. For example, when applying an absorbent article to a disposable diaper or a sanitary napkin, a pair or two or more pairs of three-dimensional guards can be disposed on the left and right sides of the topsheet.

  FIG. 1 schematically shows the cross-sectional structure of the absorbent body in the absorbent article of the present embodiment. The absorbent body 10 shown in the figure has a single-layer structure of a long fiber web (hereinafter referred to as a web) 20. The web 20 contains particles of superabsorbent polymer 21. The particles of the superabsorbent polymer 21 are embedded and supported uniformly in the web 20.

  The absorber 10 is characterized by a high absorption rate of the liquid. In particular, not only is the wearer's body pressure not applied, but it is also characterized by the fact that the absorption rate of the liquid is difficult to decrease even when the body pressure is applied. Such a feature is realized by including the pressure relaxation material 22 in the absorber 10 as shown in FIG.

  The pressure relaxation material 22 is a space for preventing the particles of the superabsorbent polymer 21 from coming close to or in close contact with the body pressure in a state where body pressure is applied to the absorbent body 10 while the absorbent article is worn. It has a role as a forming material or a spacer. The pressure relaxation material 22 acts as a column for preventing the absorber 10 and the superabsorbent polymer 21 included therein from being crushed by body pressure. As a result, even when body pressure is applied to the absorbent body 10, the particles of the superabsorbent polymer 21 are difficult to come close to or in close contact with each other, and a liquid passage is formed in the thickness direction of the absorbent body 10 as shown in FIG. 2. Secured. Thereby, the absorption speed of the liquid in the thickness direction of the absorber 10 is improved. Further, even when body pressure is applied, the absorbent body 10 and the superabsorbent polymer 21 included in the absorber 10 are not easily crushed. Therefore, the liquid absorbent capacity of the superabsorbent polymer 21 is maximized, and the performance of the absorbent body 10 is improved. .

  In particular, since the particles of the superabsorbent polymer 21 after the liquid absorption swell, the distance between the particles after the swelling becomes smaller than before the swelling, and the particles are in a state of being closer to each other or more likely to be in close contact with each other. That is, gel blocking, which is a phenomenon in which the liquid passage is blocked by the adhesion between the superabsorbent polymers 21, is likely to occur. Even in such a state, gel blocking is less likely to occur by including the pressure relaxation material 22 in the absorbent body 10. That is, even after the absorber 10 repeatedly absorbs the liquid, as shown in FIG. 2, the absorption in the thickness direction of the absorber 10 is hardly hindered, and the absorption of the liquid in the thickness direction of the absorber 10 is performed. The speed is difficult to decrease.

  From the viewpoint of increasing the absorption rate of the liquid in the thickness direction of the absorber 10 by the pressure relaxation material 22, a material made of a hydrophobic non-water-absorbing material is used as the pressure relaxation material 22. When a hydrophilic material is used as the pressure relaxation material 22, the liquid easily diffuses in the planar direction of the absorber (see FIG. 7), and it is difficult to increase the absorption rate of the liquid in the thickness direction of the absorber. If a water-absorbing material is used as the pressure relaxation material 22, the pressure relaxation material itself holds the liquid, and it is difficult to promote the permeation of the liquid in the thickness direction of the absorber. Furthermore, when the liquid is held in the pressure relaxation material 22 located near the skin side of the wearer, the inside of the wearing is easily stuffy due to the evaporation of the liquid.

  The constituent material of the pressure relaxation material 22 has a contact angle of 90 when the contact angle method (contact angle meter CA-A type manufactured by Kyowa Interface Science Co., Ltd. (FACE), droplet method) is used as a measure of hydrophobicity. It is preferable from the point of being easy to promote the permeation | transmission of the liquid to the thickness direction of an absorber.

  As described above, the pressure relaxation material 22 is made of a non-water-absorbing material. The non-water-absorbing here does not mean that it does not absorb moisture at all, and it is allowed to absorb a small amount of moisture. A material that absorbs water up to about 20% of the weight of the material itself is included in the non-water-absorbing material according to the present invention. Even if such a material is processed into a porous material and water is retained by a physical action such as capillary action, it does not hit non-water absorption.

  The shape of the pressure relaxation material 22 is not particularly limited as long as it has a role as a space forming material or a spacer. For example, as shown in FIGS. 1 and 2, the pressure relaxation material 22 may be in the form of particles. Or although not shown in figure, the pressure relaxation material 22 may be a single fiber or its aggregate | assembly. When the pressure relaxation material 22 is in the form of particles, examples of the particle shape include a spherical shape, an elliptical spherical shape, and a columnar shape. On the other hand, when the pressure relaxation material 22 is an aggregate of single fibers, the aggregate may have a shape such as a spherical shape, an elliptical spherical shape, a rod shape, or an indefinite shape.

  Whether the pressure relaxation material 22 is in the form of particles, or a single fiber or an aggregate thereof, the size of the pressure relaxation material 22 is larger than the particle size of the particles of the superabsorbent polymer 21 that has been saturated and swelled. It is important from the viewpoint that it can sufficiently serve as a space forming material or a spacer. In particular, it is important that it is larger than the particle diameter of the saturated and swollen superabsorbent polymer 21 in a state compressed by the body pressure of the wearer. From this point of view, it is necessary that the pressure relaxation material 22 has a diameter larger than the particle diameter of the superabsorbent polymer particles saturated and swollen under a load of 2 kPa (hereinafter, this particle diameter is referred to as a polymer swollen particle diameter). is there. The load of 2 kPa is a pressure that substantially corresponds to the body pressure when the absorbent article is mounted. The diameter of the pressure relaxation material 22 means the particle diameter when the pressure relaxation material 22 is in the form of particles, the diameter of the fiber when it is a single fiber, and the aggregate of single fibers. It means the minor axis of the aggregate.

  If the diameter of the pressure relaxation material 22 is larger than the polymer swelling particle size, the pressure relaxation material 22 sufficiently exhibits a role as a space forming material or a spacer. However, if the diameter of the pressure relaxation material 22 is too large, it tends to cause a feeling of discomfort. Therefore, the diameter of the pressure relaxation material 22 is preferably 1.1 to 3 times, particularly 1.3 to 2 times the polymer swelling particle size.

  The general superabsorbent polymer used for the absorbent article has a particle size of approximately 300 to 3000 μm when it is saturated and swelled. Therefore, the diameter of the pressure relaxation material 22 is preferably 330 to 9000 μm, particularly preferably 390 to 6000 μm. In the present invention, the conditions for saturation swelling of the superabsorbent polymer 21 are as follows. 1.100 g of the superabsorbent polymer is weighed into a tea bag (20 cm long, 10 cm wide rectangular bag) made of a nylon mesh having a mesh size of 63 μm (JIS 8801-2000). Then, the tea bag is immersed in 500 ml of physiological saline (0.9 wt% sodium chloride aqueous solution) for 60 minutes.

  The saturated swelling particle size of the superabsorbent polymer 21 is 100 g of which is classified using a sieve according to JIS Z-8801-1982, and the classified polymer is saturated and swelled by the above method, and the saturated swelling is performed in each fraction. Ten random polymers are taken out, taken with an optical microscope at a magnification of 10 times, and the particle size is measured.

  On the other hand, when the pressure relaxation material 22 is particulate, its diameter is determined as follows. 100 g of the pressure relaxation material 22 is weighed and classified using a sieve according to JIS Z-8801-1982. The average particle diameter is obtained from the weight fraction of each fraction, and the value is taken as the diameter of the pressure relaxation material 22.

  In the case where a single fiber is used as the pressure relaxation material 22, a material having a cross-sectional diameter larger than the polymer swelling particle size is used. Alternatively, even if the cross-sectional diameter is a single fiber smaller than the polymer swelling particle size, (b) crimp the fiber, (b) use a fiber with a cross-sectional shape that is irregular (that is, other than a circular shape). (C) Any fiber can be used in the present invention as long as the fiber occupies a larger volume by making the fiber fibrillated and the diameter of the volume is larger than the polymer swelling particle size. For example, when a crimped single fiber is used, the diameter in the occupied volume of the fiber is a value indicated by a symbol D in FIG. The diameter in the case of using a fiber having an irregular cross section is a value indicated by a symbol D in FIG. The diameter in the occupied volume of the fibrillated fiber is a value indicated by a symbol D in FIG.

  The method for increasing the occupied volume of the single fiber is not particularly limited as long as the diameter in the volume is larger than the polymer swelling particle diameter. For example, a single fiber having a larger occupied volume may be mixed in the absorbent body 10. Or even if it is a case where the state when mixed with the absorbent body 10 is a linear single fiber and the occupied volume is small, it is later in the absorbent body 10 by the action of water, pressure, heat, etc. The occupied volume may be increased.

  When the pressure relaxation material 22 is an aggregate of single fibers, the aggregate includes (a) an aggregate of hydrophobic single fibers, and (b) a single fiber in which hydrophilic fibers such as cotton, cotton, and rayon are hydrophobized. Examples of the aggregate of fibers include (c) an aggregate of single fibers which are composed of a mixture of hydrophilic fibers and hydrophobic fibers and exhibit hydrophobicity as a whole.

  Since the superabsorbent polymer 21 saturated and swollen generally has a distribution in particle size, the pressure relaxation material 22 has a distribution in the diameter as long as it has a role as a space forming material or a spacer. Alternatively, it may be a single diameter with no distribution in diameter. Further, it is desirable that all of the pressure relaxation materials 22 have a larger diameter than the polymer swelling particle size. However, since the polymer swelling particle size is distributed as described above, the pressure relaxation material 22 as a whole is not a space forming material. As long as the role as the spacer is manifested, the absorber 10 may partially include the pressure relaxation material 22 having a diameter smaller than the polymer swelling particle diameter.

  The pressure relaxation material 22 is made of a highly rigid material that is difficult to be deformed by pressure from the viewpoint of exhibiting a role as a space forming material or a spacer against the body pressure of the wearer applied during wearing of the absorbent article. It is preferable to be configured. However, if the rigidity is too high, it tends to cause discomfort. Therefore, it is also preferable to have a certain degree of softness. From these viewpoints, the material constituting the pressure relaxation material 22 preferably has a compressive elastic modulus of 0.001 to 0.5 MPa, particularly 0.005 to 0.2 MPa, and particularly 0.01 to 0.1 MPa. .

  Considering the above points comprehensively, examples of preferable materials for the pressure relaxation material 22 include silicone gel, elastomer material of synthetic resin, rubber, and the like.

  The blending amount of the pressure relaxation material 22 in the absorbent body 10 is determined in relation to the blending amount of the superabsorbent polymer 21. By setting the blending amount of the pressure relaxation material 22 to an appropriate value, gel blocking of the superabsorbent polymer 21 is effectively prevented, and a liquid passage for allowing liquid to permeate in the thickness direction of the absorbent body 10 is ensured. Secured. From this viewpoint, it is preferable that the absorber 10 contains the pressure relaxation material 22 0.1 to 2 times, particularly 0.5 to 1.5 times the weight of the particles of the superabsorbent polymer 21.

  In this embodiment, the pressure relaxation material 22 is mix | blended with the absorber 10, the gel blocking of a superabsorbent polymer is prevented, and the liquid absorption rate of the absorber 10 is raised. Therefore, in this embodiment, it is easy to make the amount of the superabsorbent polymer 21 relatively large with respect to the amount of the web 20 that is a fiber material. This is very advantageous in that the liquid absorption capacity can be improved without increasing the thickness of the absorber 10. From this viewpoint, in the absorbent body 10, the weight ratio of the superabsorbent polymer 21 to the long fibers (superabsorbent polymer / long fibers) is preferably set to 2 or more, and more preferably set to 3 or more. The upper limit of the weight ratio of the superabsorbent polymer 21 to the long fibers is determined from the viewpoint of extreme movement of the superabsorbent polymer 21 and prevention of falling off. Although depending on the presence / absence of crimping of the long fibers and the degree of crimping, if the upper limit is about 10, even if the wearer performs a violent operation, the superabsorbent polymer is unlikely to move or fall off.

  As the superabsorbent polymer 21, the same polymers as those conventionally used for absorbent articles can be used. For example, polyacrylic acid soda, (acrylic acid-vinyl alcohol) copolymer, crosslinked polyacrylic acid soda, (starch-acrylic acid) graft polymer, (isobutylene-maleic anhydride) copolymer and saponified product thereof, poly Examples include potassium acrylate and polycesium acrylate.

  In the embodiment shown in FIG. 1, the pressure relaxation material 22 is uniformly mixed and dispersed in the absorbent body 10 together with the particles of the superabsorbent polymer 21. However, the distribution of the pressure relaxation material 22 is not limited to this. For example, the pressure relaxation material 22 may be biased toward the skin facing surface side of the web 20. Alternatively, the pressure relaxation material 22 may be biased in the web 20 toward the skin non-facing surface side of the web 20. When the pressure relaxing material 22 is biased toward the skin facing surface side or the skin non-facing surface side of the web 20, the amount of the pressure relaxing material 22 may continuously change in the thickness direction of the web 20. Alternatively, it may change step by step.

  FIG. 4 shows another example of the absorbent body 10 according to the absorbent article of the present invention. The absorbent body 10 of the present embodiment includes the same or different types of webs 20 and 20 and a spray layer of the pressure relaxation material 22. The absorber 10 includes a plurality of webs 20, and a spray layer of the pressure relaxation material 22 is located between the webs 20 and 20. There is no restriction | limiting in particular in the upper limit of the number of layers of a web, A suitable number of webs are used according to the specific use of an absorbent article. A part of the pressure relaxation material 22 is carried in the web 20. Further, the superabsorbent polymer 21 particles are embedded and supported in the web 20. The absorbent body 10 according to the present embodiment can be regarded as the pressure relaxation material 22 being biased at the central portion in the thickness direction of the web 20.

  FIG. 5 shows still another example of the absorbent body 10 according to the absorbent article of the present invention. In the absorbent body 10 of this embodiment, a spray layer of a pressure relaxation material 22 is formed on the upper surface of a long fiber web 20 containing particles of a superabsorbent polymer 21. In addition, although not shown in figure, these are entirely coat | covered with the coating sheet which has liquid permeability. According to the absorbent body 10 of the present embodiment, since the pressure relaxation material 22 located on the upper surface of the web 20 receives and disperses the body pressure of the wearer, the particles of the superabsorbent polymer 21 absorb water. Even if the body pressure is received under the swollen state, the particles are difficult to come close to or in close contact with each other, and a liquid passage for allowing liquid to permeate in the thickness direction of the absorber 10 is secured.

  In any case of FIG. 1, FIG. 4, and FIG. 5, it is preferable that the long fibers constituting the web 20 have hydrophilicity. What is used in the present invention as a long fiber having hydrophilicity is a long fiber that is inherently hydrophilic, and inherently has no hydrophilicity, but is hydrophilic by being subjected to a hydrophilic treatment. Both of the long fibers to which is given are included. Preferred long fibers are inherently hydrophilic long fibers, and particularly preferred are acetate and rayon long fibers. In particular, acetate is particularly preferable because it retains bulkiness even when wet. As the acetate, cellulose triacetate and cellulose diacetate are preferable.

  The long fibers constituting the web 20 are preferably oriented in one direction in the plane direction of the absorbent body 10. When the liquid is absorbed by the absorbent body 10 due to the orientation of the long fibers in one direction, the liquid diffuses preferentially in the orientation direction of the long fibers. That is, it diffuses preferentially in the planar direction of the absorber 10. Conversely, diffusion in the direction perpendicular to the orientation direction of the long fibers is suppressed. When long fibers are oriented in the longitudinal direction of the absorbent article, liquid leakage (lateral leakage) from the side of the absorbent article is effectively prevented. On the other hand, when the long fibers are oriented in the width direction of the absorbent article, diffusion in the longitudinal direction of the absorbent article is suppressed, and spot absorptivity is obtained.

As the long fibers constituting the web 20, it is preferable to use crimped ones. The long fiber preferably has a crimp ratio (JIS L0208) of 10 to 90%, particularly 10 to 60%, particularly 20 to 50%. By forming the web 20 from the crimped long fibers, it becomes easy to embed and carry the superabsorbent polymer 21 stably and in a large amount in the web 20. There is no particular limitation on the means for crimping the long fibers. Further, the crimp may be two-dimensional or three-dimensional. The crimp rate is defined as a percentage of the difference between the length A when the long fiber is stretched and the length B of the original long fiber with respect to the length A when stretched, and is calculated from the following equation: .
Crimp rate = (A−B) / A × 100 (%)

  The length of the original long fiber means a length in which both ends of the long fiber are connected with a straight line when the long fiber is in a natural state. The natural state means a state in which one end of the long fiber is fixed to a horizontal plate and hung downward by its own weight. The length when the long fiber is stretched refers to the length at the minimum load when the long fiber is stretched until there is no crimp.

  The crimp rate of the long fibers is as described above, and the number of crimps is preferably 2 to 25, particularly 4 to 20, especially 10 to 20 per cm.

  The fiber diameter of the long fiber is related to the supportability of the superabsorbent polymer. On the condition that the basis weight of the web 20 is the same, satisfactory supportability can be obtained by using long fibers of 1.0 to 7.8 dtex, particularly 1.7 to 7.8 dtex. In the present invention, the long fiber means a fiber having a fiber length of preferably 70 mm or more, more preferably 80 mm or more, and even more preferably 100 mm or more when the fiber length is measured by the average fiber length measurement method (Method C) of JIS L1015. Say. However, when the total length of the web to be measured is less than 100 mm, preferably 50% or more, more preferably 70% or more, more preferably 80% or more of the fibers in the web extend over the entire length of the web. In this case, it is assumed that the fibers of the web are long fibers. The long fibers used in the present invention are generally called continuous filaments. A bundle of continuous filaments is generally called a tow. Therefore, the long fiber in the present invention is a concept including a continuous filament. The web in which the long fibers are oriented is a concept including a bundle of long fibers (so-called tow) as a raw material for forming the web and a tow layer of continuous filaments.

Appropriate values are selected for the thickness and basis weight of the absorbent body 10 having the structure shown in FIGS. 1, 4, and 5 according to the specific application of the absorbent article. For example, when used as an absorbent body for disposable diapers for infants, the web 20 preferably has a basis weight of 5 to 200 g / m ² , particularly 10 to 100 g / m ² . The spreading basis weight of the pressure relaxation material 22 is preferably 10 to 300 g / m ² , particularly preferably 25 to 150 g / m ² . The spreading basis weight of the superabsorbent polymer 21 is preferably 50 to 500 g / m ² , particularly preferably 100 to 300 g / m ² .

When used as an absorbent body of a sanitary napkin, each web 20 preferably has a basis weight of 5 to 100 g / m ² , particularly 10 to 50 g / m ² . The spreading basis weight of the pressure relaxation material 22 is preferably 1 to 80 g / m ² , particularly preferably 3 to 30 g / m ² . The spreading basis weight of the superabsorbent polymer 21 is preferably 10 to ²⁰⁰ g / m ² , particularly preferably 15 to 100 g / m ² . When used as an absorbent body for an incontinence pad, each web 20 preferably has a basis weight of 5 to 200 g / m ² , particularly 10 to 100 g / m ² . The spreading basis weight of the pressure relaxation material 22 is preferably ³ to 300 g / m ² , particularly preferably 5 to 200 g / m ² . The spreading basis weight of the superabsorbent polymer 21 is preferably 10 to 500 g / m ² , particularly preferably 15 to 350 g / m ² .

The total basis weight of the web 20, the pressure relaxation material 22 and the superabsorbent polymer 21 in the absorbent body 10 is preferably 120 to 400 g / m ² , particularly 150 to 300 g when the absorbent body 10 is used for a disposable diaper, for example. / M ² . When used for a sanitary napkin, it is preferably 35 to 200 g / m ² , particularly 50 to 150 g / m ² . When used for an incontinence pad, it is preferably 35 to 500 g / m ² , particularly 50 to 400 g / m ² .

  The absorbent body 10 may be composed only of the web 20 containing the pressure relaxation material 22 and the superabsorbent polymer 21, or the web 20 containing these may be wrapped with, for example, various sheet materials. Moreover, various sheet materials may be arranged on the upper surface and / or the lower surface of the web 20, and the whole may be wrapped with another sheet material. Examples of the sheet material include paper such as fluff pulp and tissue paper, dry pulp sheets, and nonwoven fabrics (for example, air-through nonwoven fabric and airlaid nonwoven fabric). When the absorbent body 10 is used in a disposable diaper, it is preferable that the thickness of the absorbent body 10 is 1 to 4 mm, particularly 1.5 to 3 mm, regardless of the shape of the absorbent body 10. . When used for a sanitary napkin, it is preferably 0.5 to 3 mm, particularly preferably 1 to 2 mm. When used as an incontinence pad, it is preferably 0.5 to 4 mm, particularly 1 to 3 mm.

The thickness of the absorbent body 10 is measured under a state where an acrylic plate having a size of 5 cm × 5 cm is placed on the absorbent body 10 and a weight is further placed thereon, and a load of 2.5 g / cm ² is applied. In this embodiment, the thickness was measured using an LK080 class 2 laser displacement meter manufactured by Keyence Corporation. The number of measurement points was an average of 5 points, and when the measurement value fluctuated 20% or more, the data was deleted and another measurement value was added. A 250 g / cm ² load was previously applied to the sample for 12 hours to keep the wrinkles extended.

  FIG. 6 shows still another example of the absorbent body 10 according to the absorbent article of the present invention. The absorbent body 10 shown in the figure is different from the embodiments described so far in the types of fiber materials contained therein. Specifically, in the embodiments described so far, a long fiber web is used as the fiber material of the absorbent body 10, but in this embodiment, pulp is used as the fiber material. The absorbent body 10 shown in FIG. 6 includes particles of pulp 23, pressure relaxation material 22, and superabsorbent polymer 21. These three are uniformly mixed.

  Also in the present embodiment, the particles of the superabsorbent polymer 21 are difficult to come close to or in close contact with each other even when body pressure is applied to the absorbent body 10 due to the action of the pressure relaxing material 22 as a space forming material or spacer. As a result, a liquid passage is ensured in the thickness direction of the absorbent body 10 and the liquid absorption speed in the thickness direction of the absorbent body 10 is improved. Note that the description regarding the embodiment described above is applied as appropriate to points that are not particularly described regarding the embodiment illustrated in FIG. 6.

  As mentioned above, although this invention was demonstrated based on the preferable embodiment, this invention is not restrict | limited to the said embodiment. For example, in the embodiment shown in FIGS. 1, 4, and 5, an absorbent body may be configured by arranging a fiber pile layer including or not including a superabsorbent polymer below the web 20. .

  In the embodiment shown in FIGS. 1, 4, 5, and 6, a state where a particulate material is used as the pressure relaxation material 22 is shown. However, instead of or in addition to this, pressure relaxation is performed. Single fibers and / or aggregates thereof may be used as the material.

It is a mimetic diagram showing the section structure of an example of the absorber concerning the absorptive article of the present invention. It is a schematic diagram which shows the state of the liquid absorption by the absorber shown in FIG. It is a schematic diagram which shows the fiber of the state which made the occupation volume large. It is a schematic diagram which shows the cross-section of the other example of the absorber which concerns on the absorbent article of this invention. It is a schematic diagram which shows the cross-section of the further another example of the absorber which concerns on the absorbent article of this invention. It is a schematic diagram which shows the cross-section of the further another example of the absorber which concerns on the absorbent article of this invention. It is a schematic diagram which shows the state of the liquid absorption by the absorber in the conventional absorbent article.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Absorber 20 Long fiber web 21 Super absorbent polymer 22 Pressure relaxation material 23 Pulp

Claims (5)

An absorbent article comprising an absorbent body comprising fibrous material and particles of superabsorbent polymer,
The absorber further includes a pressure relaxation material made of a hydrophobic non-water-absorbing material,
The absorbent article, wherein the pressure relaxation material has a larger diameter than the particle diameter of the saturated absorbent swollen superabsorbent polymer particles under a 2 kPa load.   The absorptive article according to claim 1 in which said textile material contained in said absorber consists of a web or pulp of a long fiber.   The absorptive article according to claim 1 or 2 in which said pressure relaxation material comprises particles, single fiber, or its aggregate.   The absorbent article according to any one of claims 1 to 3, wherein the constituent material of the pressure relaxation material is silicone gel, elastomer resin, or rubber. The absorbent article according to any one of claims 1 to 4, wherein the pressure relaxation material is contained in an amount of 0.1 to 2 times the weight of the particles of the superabsorbent polymer.

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