JP4480688B2 - Absorbent articles - Google Patents

Description

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

  A pants-type disposable diaper having a stretchable side panel is known (see, for example, Patent Document 1). This type of pants-type disposable diaper tends to be in close contact with the wearer's body due to the stretchability of the side panel. Therefore, a gap is hardly generated between the wearer's body and the diaper. This works positively from the viewpoint of preventing leakage. On the other hand, the water vapor generated from the wearer's body tends to stay in the dressing, and the humidity tends to rise, resulting in a negative effect of causing stuffiness.

  In the diaper, the side panel may be breathable or moisture permeable in addition to stretchability. By doing so, it is possible to suppress the increase in humidity in the wearing to some extent. However, the most prone to stuffiness is the absorbent body and its vicinity rather than the side panel, so that stuffiness cannot be sufficiently prevented only by imparting air permeability to the side panel. Further, if the absorption amount of the absorbent body is reduced, the absorbent body becomes thinner and the air permeability of the absorbent body is improved. However, on the other hand, leakage tends to occur.

Japanese Patent Publication No. 8-17792

  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 comprises an absorbent body comprising a hydrophilic long fiber web and a superabsorbent polymer, and the airflow resistance value of the absorbent per 100 g / m ^{2 of the} superabsorbent polymer is 0.4 kPa · s. The above-mentioned object is achieved by providing an absorbent article having a / m or less.

  In the absorbent article of the present invention, since the absorbent body has a long fiber web having hydrophilicity, the absorbent body has high flexibility and is sufficient without degrading the absorbent performance. Air permeability can be secured. As a result, according to the absorbent article of the present invention, the fit to the wearer's body is enhanced, and the increase in humidity in the wearing during wearing is suppressed.

  The present invention will be described below based on preferred embodiments with reference to the drawings. FIG. 1 shows a disposable diaper as an embodiment of the absorbent article of the present invention. 2 is a cross-sectional view taken along line II-II in FIG. The diaper 1 of this embodiment is disposed between a liquid-permeable top sheet 2, a liquid-impermeable or water-repellent (hereinafter collectively referred to as liquid-impermeable) back sheet 3, and both sheets. The liquid-retaining absorbent body 4 is provided and is formed substantially vertically long.

  As the surface sheet 2, a non-woven fabric, a material in which a large number of holes are formed, or a perforated film can be used. The top sheet 2 has air permeability in addition to being liquid permeable. The back sheet 3 has moisture permeability in addition to being liquid impermeable. In the present invention, the term “air permeability” mainly refers to a property related to air permeability. In addition, the term “moisture permeability” mainly refers to a property related to water vapor permeability. Being breathable means not only air but also water vapor permeability. Similarly, being moisture permeable means not only water vapor but also air permeability.

  The diaper 1 has an hourglass shape in which both side edges of the crotch portion are curved in an arc shape and the central portion in the longitudinal direction is bound inward as a whole. The top sheet 2 and the back sheet 3 respectively extend outward from the left and right side edges and front and rear end edges of the absorber 4. The top sheet 2 has a width dimension that is smaller than the width dimension of the back sheet 3. As a result, the left and right side edges 2a and 2b of the top sheet 2 are terminated more inward in the width direction than the left and right side edges 3a and 3b of the back sheet 3.

  An exterior sheet 5 having air permeability is disposed on the outer surface of the back sheet 3. The exterior sheet 5 and the back sheet 3 are bonded together by, for example, a hot melt adhesive. In order not to impair the moisture permeability of the back sheet 3, the hot melt pressure-sensitive adhesive is applied in an intermittent pattern such as bead coating or spiral coating. The exterior sheet 5 extends outward from the left and right side edges and the front and rear end edges of the top sheet 2 and the back sheet 3 to define the outline of the diaper 1. As a material of the exterior sheet 5, for example, various nonwoven fabrics are used.

  A pair of three-dimensional gathers 6 and 6 and a pair of leg gathers 7 and 7 are formed on both sides in the longitudinal direction of the diaper 1 by disposing elastic members, respectively. Both gathers 6 and 7 extend in the longitudinal direction of the diaper 1. The three-dimensional gather 6 is formed from a sheet material 62 for forming a three-dimensional gather having an elastic member 61. The function of the three-dimensional gather 6 is a barrier for preventing the liquid diffused in the lateral direction without being absorbed by the absorber 4 from further diffusing in the lateral direction. It is preferable that. Moreover, it is preferable to have air permeability from a viewpoint of suppressing the humidity rise in the wearing during wearing of the diaper 1.

  Moreover, two or more sets of solid gathers may be used as well as a pair of left and right. The reason is as follows. From the viewpoint of ensuring the air permeability of the absorber 4 and its vicinity, it is desirable to make the absorber thinner and to make the average density as small as possible. However, such absorbers can be used for temporary fluid stocking when large amounts of urine are excreted or when urine is excreted at a high rate (eg when the wearer is an older infant or adult). There may be a situation where there is not enough room for the Therefore, it is preferable to use two or more pairs of three-dimensional gathers from the viewpoint of preventing leakage. Details of the absorbent article provided with two or more pairs of three-dimensional gathers will be described later.

  From the above viewpoints, as the sheet material 62, it is preferable to use a non-woven fabric, an apertured film, or the like that has water repellency per se or has been subjected to water repellency treatment. The perforated film includes the concept of a sheet having water vapor permeability described later. In particular, it is preferable to use a nonwoven fabric or a laminate of a nonwoven fabric and an apertured film. Examples of preferred non-woven fabrics include thermal bond non-woven fabrics, spunbond non-woven fabrics, spunbond-meltblown-spunbond non-woven fabrics, using fibers solely using thermoplastic resins such as polyethylene, polypropylene, polyethylene terephthalate, or composite fibers thereof. Spunbond-meltblown-meltblown-spunbond non-woven fabric and the like.

  The sheet material 62 forming the three-dimensional gathers may be formed by combining these nonwoven fabrics and elastic bodies, or a sheet obtained by combining a nonwoven fabric with a fibrous elastomer material in advance to give stretchability. May be. Examples of a method for imparting stretchability include a method in which an elastomer and a non-woven fabric are combined under non-extension, and then the non-woven fabric is subjected to slit processing or some kind of crushing treatment.

  The sheet material 62 has a vertically long shape extending in the longitudinal direction of the diaper 1, and an elastic member 61 is fixed to the one side edge in an extended state. The sheet material 62 is joined to the topsheet 2 along the longitudinal direction of the diaper 1 at positions outside the left and right side edges of the absorbent body 4 in the width direction. The joint portion is a rising base end portion 6 a of the three-dimensional gather 6.

  It is preferable that the sheet material 62 extends outward in the width direction from the base end portion 6a, and is bonded to a moisture-permeable sheet at the extended portion. For example, as shown in FIG. 2, it is preferable that the sheet material 62 and the back sheet 3 are directly joined from the viewpoint of preventing liquid diffusion of the three-dimensional gather 6 and improving the leak-proof property of the diaper 1. More specifically, as shown in FIG. 2, the sheet material 62 further extends outward in the width direction from the base end portion 6a. In the middle of the extended portion, the sheet material 62 is directly joined to the back sheet 3. Further, the sheet material 62 is joined to the exterior sheet 5 at the distal end portion of the extending portion. As a result, a leg flap L (see FIG. 2) is formed. In the leg flap L, one or a plurality of (in the present embodiment, a plurality of) leg elastic members 71 are arranged in a substantially straight line to form a leg gather 7. The leg elastic member 71 includes the sheet material 62 and the exterior sheet 5 in a region between the position where the extended portion of the sheet material 62 is joined to the back sheet 3 and the position joined to the exterior sheet 5. Between the two.

  As described above, the sheet material 62 has air permeability. Similarly, the exterior sheet 5 has air permeability, and the back sheet 3 has moisture permeability. Therefore, the leg flap L has air permeability or moisture permeability. Therefore, in the diaper 1, the outer part in the width direction from the left and right side edges of the absorbent body 4 has air permeability or moisture permeability. In other words, the portion between the leg elastic member 71 located on the outermost side in the width direction and the side edge of the absorber 4 has air permeability or moisture permeability.

  The configuration of the left and right sides of the diaper 1 is as described above, while the configuration of the front and rear ends of the diaper 1 is as follows. At the front and rear ends of the diaper 1, the front sheet 2, the back sheet 3, and the exterior sheet 5 extend from the front and rear end edges of the absorber 4, and these are joined to each other and a waist flap W extending in the width direction of the diaper 1 (see FIG. 1). Since all of these sheets constituting the waist flap W have air permeability or moisture permeability, the waist flap W has air permeability or moisture permeability.

  In the waist flap W, one or a plurality of waist elastic members 81 extending in the width direction are arranged between the sheets described above (one in the present embodiment) to form the waist gathers 8. As described above, since the waist flap W has air permeability or moisture permeability, the portion between the waist elastic member 81 located on the outermost side in the longitudinal direction and the edge of the absorber 4 is air permeable. It has moisture permeability. In the present embodiment, the waist elastic members are disposed on the front and rear waist flaps W. However, depending on the specific use of the diaper 1, the waist elastic members are provided only on one of the front and rear waist flaps W. It may be arranged.

  At one end in the longitudinal direction of the diaper 1, a pair of fastening tapes FT are attached to both side edges. Further, a landing tape LT is attached on the exterior sheet 5 at the other end. The fastening tape FT and the landing tape LT are configured such that the fastening tape FT is fixed to the landing tape LT when the diaper 1 is worn. For example, the fastening tape FT and the landing tape LT are a combination of a loop member and a hook member of a hook-and-loop fastener.

  As shown in FIG. 2, the absorbent body 4 in the diaper 1 has a long fiber web 4a having hydrophilicity. A superabsorbent polymer 4b is embedded and supported on the web 4a. The absorbent body 4 is characterized by being thin and having a low basis weight and having a high air permeability while having a sufficient absorption capacity.

  Imbedded support means that a superabsorbent polymer enters a space formed by long fibers (especially crimped long fibers), and the polymer is unlikely to move or fall off even when the wearer moves vigorously. Say the state. At this time, the long fibers are entangled or caught in the superabsorbent polymer, or the superabsorbent polymer is attached to the long fiber due to its own stickiness. The space formed by the long fibers is easily deformed even when stress is applied from the outside, and the entire long fibers can absorb the stress, thereby preventing the space from being destroyed. The superabsorbent polymer is at least partially embedded and supported in the web 4a. Depending on the manufacturing conditions of the absorbent body 1, almost all of the superabsorbent polymer may be uniformly embedded and supported in the web 4a.

  There is no restriction | limiting in particular in the fiber diameter of a long fiber. In general, satisfactory results are obtained by using long fibers of 1 to 10 dtex, in particular 1.7 to 7.8 dtex. In addition, when it is desired to give the absorbent body kinking resistance or cushioning properties, it is particularly preferable to use fibers of 2.1 to 7.2 dtex. In the present specification, 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. In addition, fibers (cut fibers) in which part of the long fibers are cut and the fiber length is less than the above value may be mixed in the absorbent body.

  As described above, the long fibers 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 nylon, acrylic, acetate, and rayon long fibers are particularly preferable. In particular, acetate is particularly preferable because it retains bulkiness even when wet. As the acetate, cellulose triacetate and cellulose diacetate are preferable. In particular, acetate, which is a fiber having a moisture content of less than 10%, is particularly preferable because it retains its bulkiness even when wet. Here, the moisture content is a value measured in an environment of 25 ° C. and a relative humidity of 65%.

  In the present specification, the hydrophilic web refers to one having a Klem water absorption measured in the orientation direction of preferably 20 mm or more, more preferably 30 mm or more. The measurement of Klem water absorption is performed, for example, as follows. The superabsorbent polymer is removed from the portion of the absorber 1 containing the superabsorbent polymer, and the crimped rate of the long fiber in the absorber 1 is maintained, and the web of the long fiber is used to absorb the Krem. Measure the degree. For the measurement, ion-exchanged water colored with 0.3% red No. 2 (external addition) is used. The height from the water surface 30 seconds after the setting is taken as the Klem water absorption. The Klem water absorption is measured according to JISP8141 (1996) “Test method for water absorption by the Krem method of paper and paperboard”. As the measurement direction, only the longitudinal direction of the absorber 1 is measured. The test piece has a width of 15 mm. The average value of the measured values of the three test pieces is taken as the Krem water absorption. Depending on the test piece, the Klem water absorption varies in the width direction. In this case, a value obtained by substantially averaging (visually) the width direction is taken as the measurement value.

When the operation of removing the superabsorbent polymer from the absorbent body is performed, the web density ρ1 in the absorbent body may be different from the web density ρ2 after the superabsorbent polymer is removed. Therefore, before removing the superabsorbent polymer from the absorbent body, the density ρ1 of the web in the absorbent body was measured in advance, and the density ρ2 of the web after the superabsorbent polymer was removed was measured in advance. After adjusting the state of the web after the superabsorbent polymer is removed so as to be the same as the density ρ1, the Krem water absorption is measured. In order to adjust the density ρ2 to the density ρ1, for example, the web after the superabsorbent polymer is removed may be compressed, and the Klem water absorption is measured in that state. The density ρ1 was, for example, 0.03 to 0.05 g / cm ³ .

The density ρ1 (g / cm ³ ) of the web in the absorber is calculated from the basis weight (g / cm ² ) of the web and the thickness (cm) of the web. The basis weight of the web is calculated from the weight (g) after removing the superabsorbent polymer from the absorbent body and the area (cm ² ). On the other hand, the thickness of the web is measured by the following method. A wrinkle is extended by applying a load of 24.5 kPa to the absorbent body taken out from the absorbent article in advance for 12 hours. Next, a weight is placed on an acrylic plate having a size of 5 cm × 5 cm on the absorber, and the thickness is measured under a state where a load of 0.245 kPa is applied. Specifically, a cross section of the absorber is cut out with a razor blade, the range of the absorber including the web is observed with a 10-fold stereo microscope, and the thickness of the web in the absorber is measured. The number of measurement points is 5, and the average value is the thickness. If the measured value fluctuates by 20% or more, delete the data and add another measured value.

  As the long fiber, it is preferable to use a crimped one. The long fiber has a crimp rate (JIS L0208) of preferably 10 to 90%, more preferably 10 to 60%, and still more preferably 10 to 50%. By using the crimped long fibers having a crimp rate in this range, the packing density of the fibers in the absorbent body does not become excessively high, and the air permeability of the absorbent body described later is improved. Further, when the crimping rate is within this range, the highly absorbent polymer can be stably embedded in a large amount in the web 4a. That is, by setting the crimp rate of the long fibers within the above range, it is possible to achieve both the air permeability and the absorption performance of the absorbent body. 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 the percentage of the difference between the length when the long fiber is stretched and the length of the original long fiber to the length when stretched. 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 crimp rate is the length (A) when the long fiber is stretched straight and without stretching the fiber itself, and the length of the straight line (B) between the start point and the end point of the fiber in the natural state. ) Is defined as a percentage of the length (A) when stretched, and is calculated from the following equation.
Crimp rate = ((A−B) / A) × 100 (%)

  As the superabsorbent polymer, a particulate polymer is generally used, but a fibrous polymer may be used. When a particulate superabsorbent polymer is used, if the shape is an irregular type, a block type, or a bowl type, it is buried with a basis weight equal to or greater than 10 times the weight of the web 4a. Can be made. Further, in the case of a spherical particle aggregation type or a spherical type, it can be embedded and supported at a basis weight equal to or more than 5 times the weight of the web 4a. For these particle shapes, it is desirable to select the former when it is particularly desired to achieve both high absorption and thinning, and the latter when importance is placed on the texture (reduction of the feeling of shaving of the superabsorbent polymer). The superabsorbent polymer may be distributed uniformly in the thickness direction of the web 4a, or may be distributed unevenly on the top sheet 2 side or the back sheet 3 side. Further, the web 4a may be uniformly distributed in the planar direction or may be distributed so as to form a predetermined pattern. What is necessary is just to select suitably the aspect of distribution of a superabsorbent polymer according to the specific use of the diaper 1. FIG.

  When the long fiber has crimps, the web 4a has a large number of spaces that can hold particles of the superabsorbent polymer. The superabsorbent polymer is retained in the space. As a result, even if a large amount of superabsorbent polymer is sprayed, the extreme movement or dropout is less likely to occur. Moreover, even if a wearer performs intense operation | movement, the structure of the absorber 4 becomes difficult to be destroyed. Depending on the superabsorbent polymer used, the crimp rate and the amount of long fibers used are adjusted as appropriate.

  Even in the conventional absorbent body, if the amount of the fiber material is increased, a large amount of the superabsorbent polymer can be retained, but in this case, the basis weight and thickness of the absorbent body are increased. In that case, it is not possible to obtain an absorber having a reduced airflow resistance which is an effect of the present invention, that is, having a high air permeability. On the other hand, in the present invention, the amount of the superabsorbent polymer is relatively large with respect to the amount of the fiber material. Specifically, the basis weight of the superabsorbent polymer is preferably not less than the basis weight of the web, more preferably not less than 2 times, more preferably not less than 3 times when viewed from the whole absorbent body. As a result, the absorber 1 is made thinner and has a lower basis weight. As a result, the stretch response of the absorbent body 1 is good. The upper limit of the ratio of the basis weight of the superabsorbent polymer to the basis weight of the web is determined from the viewpoint of extreme movement of the superabsorbent polymer and prevention of falling off. Depending on the degree of crimp of the long fibers, the upper limit is 20 times or less, preferably 15 times or less, and more preferably 10 times or less. Extreme movement and dropout are unlikely to occur.

  The supportability of the superabsorbent polymer on the long fiber web is related to the network structure formed by the web and the physical properties of the superabsorbent polymer. From the viewpoint of the network structure, in the present invention, the steric regularity of the web, that is, the web is controlled by controlling the crimp rate, fineness, density, etc. of the web so that the supportability of the superabsorbent polymer is expressed. I have to. In the present invention, since the constituent fibers of the web are not bonded to each other, the size of the network formed on the web can be changed to such an extent that the superabsorbent polymer can be retained. Since the size of the mesh in the web can be changed, the supportability of the polymer becomes higher compared to the case where the superabsorbent polymer is supported on a fiber assembly having a bonding point such as a nonwoven fabric. The size of the mesh can be determined by, for example, (a) applying a superabsorbent polymer in a state where a fiber is tensioned and then releasing the tension, or (b) controlling the web tension in advance. It can be controlled by spraying a superabsorbent polymer under a state in which a shrinkage ratio is expressed, and further applying tension or pressure to the web.

  On the other hand, the physical properties of the superabsorbent polymer related to the supportability of the superabsorbent polymer include shape, particle size distribution, particle size, bulk density, surface properties, internal friction coefficient, fluidity, dispersibility, moisture content, charging Properties, adhesion, and cohesion. Among these, the particle size distribution and particle size of the superabsorbent polymer are closely related to the above-described web network structure. The carrying ability of the superabsorbent polymer is also affected by the number of collisions between the polymer and the long fibers inside the absorbent body when an external force or vibration is transmitted to the absorbent body due to the movement of the wearer. The higher the number of collisions, the higher the absorbency of the polymer, and the higher absorbability polymer screens according to the network formed by the long fibers, resulting in lower supportability. The number of collisions is affected by the fluidity of the polymer. The number of collisions increases as the fluidity of the superabsorbent polymer increases. In addition, the superabsorbent polymer which has high fluidity and has once escaped from the restraint of the web easily moves and becomes difficult to be supported on the web.

  Regarding the flowability of the superabsorbent polymer, comparing the bulk type superabsorbent polymer and the spherical aggregate type polymer, the spherical aggregate type superabsorbent polymer is more fluid than the bulk type superabsorbent polymer. High nature. As a result, the bulk type superabsorbent polymer has higher supportability than the spherical particle aggregate type superabsorbent polymer. In addition, since the superabsorbent polymer of the spherical particle agglomeration type has a smooth surface, the degree of friction with the fiber and catching on the fiber is lower than that of the bulky type superabsorbent polymer. Also from this viewpoint, the bulk type superabsorbent polymer has higher supportability than the spherical particle aggregate type superabsorbent polymer.

  As described above, the present invention has been devised in terms of the crimp rate of the long fibers, the shape of the superabsorbent polymer, the mixing ratio of the long fibers and the superabsorbent polymer, the method for supporting the superabsorbent polymer on the long fiber web, and the like. It is possible to lower the ventilation resistance value which is the effect of.

The absorber 4 having the above structure is thin, has a low basis weight, and has a high air permeability. The degree of air permeability of the absorbent body 4 is 0.4 kPa · s / m or less, preferably 0.3 kPa · s / m or less, expressed as an air resistance per 100 g / m ^{2 of the} superabsorbent polymer. The smaller the ventilation resistance value, the higher the air permeability. Such a ventilation resistance value is an extremely low value of about ½ of the ventilation resistance value of a conventional absorbent body made of a laminate of flap pulp and a superabsorbent polymer. There is no restriction | limiting in particular in the minimum of ventilation resistance value, and the air permeability becomes high, so that the value is small. The ventilation resistance value is measured by an air permeability tester KES-F8 (trade name) manufactured by Kato Tech. According to this apparatus, the pressure loss when a constant flow rate of air (4 cc square cm / sec) is passed is measured. The measured ventilation resistance value is converted into a value per 100 g / m ^{2 of the} superabsorbent polymer.

  Some of the absorbent bodies according to the present invention have a ventilation resistance value of not more than the measurement limit of the measuring device, that is, not more than about 0.2 kPa · s / m. For example, a material in which a superabsorbent polymer is supported in a long fiber web and wrapped with tissue paper without using pulp as a constituent material of the absorbent body can be mentioned. Therefore, in the present invention, there is no lower limit value for the ventilation resistance value. Examples of other materials that are less than or equal to the measurement limit of the measuring device include normal tissue paper, surface sheets, and gauze used for absorbent articles.

  The absorbent body 4 including the long fiber web 4a has high air permeability in both the thickness direction and the planar direction. Therefore, during wearing of the diaper 1, water vapor released from the wearer's body is effectively released to the outside of the diaper 1 through the absorber 4. As a result, an increase in humidity within the wearing is effectively suppressed.

The water vapor release path in the diaper 1 of the present embodiment is roughly divided into two paths in the thickness direction and the planar direction. The discharge path in the thickness direction is such that the water vapor moves through the absorber 4 in the thickness direction, and the diaper 1 passes through the back sheet 3 which is a sheet having water vapor permeability (moisture permeability) and the outer sheet 5 which is a breathable sheet. It is a route released to the outside. From the viewpoint of more effectively releasing water vapor through this route, the back sheet 3 has a moisture permeability (JIS Z0208) of 0.6 to 3.5 g / (100 cm ² · h), particularly 1 to 3 g / (100 cm ^2. H) is preferred. Moisture permeability Within this range, it is possible to ensure sufficient water vapor permeability while preventing the liquid absorbed by the absorbent body 4 from oozing out and to prevent the occurrence of stuffiness and rash. The moisture permeability is measured according to JIS Z0208 (cup method) under the condition of 30 ° C./90% RH.

  As the sheet having water vapor permeability, for example, a porous sheet can be used. The porous sheet is formed by stretching a sheet formed from a melt-kneaded product of the resin composition. The porous sheet preferably has sufficient moisture permeability of the sheet while maintaining moldability and sheet strength. Moreover, you may perform an embossing process and various surface treatments as needed to the obtained porous sheet. Furthermore, it may be used in combination with other sheets, for example, an exterior sheet 5 such as nonwoven fabric or paper.

In the planar water vapor release path, the water vapor moves in the planar direction inside the absorber 4 and is released from the side or end of the absorber 4 to the outside of the diaper 1 through the leg flap L or the waist flap W. It is a route. As described above, since the leg flap L or the waist flap W in the diaper 1 of the present embodiment has air permeability or moisture permeability, water vapor is smoothly discharged through these flaps. In particular, in the leg flap L, the left and right side edges of the top sheet 2 terminate inwardly than the left and right side edges of the back sheet 3, so the number of sheets constituting the leg flap L is reduced. Only the air permeability or moisture permeability of the leg flap L is improved. From the viewpoint of more smoothly releasing water vapor through the leg flaps L and the waist flaps W, when joining sheets to form these flaps, for example, hot-melt adhesive is used for bead coating or spiral coating, It is preferable to apply a pattern such as spray coating to prevent a decrease in air permeability as much as possible. A coating method in which the entire coated surface is covered with a film is not preferable. For example, when coating with a coater, a comb-blade or intermittent coating method is preferred. Even with the whole surface coating method, the coating amount is sufficiently reduced and the coating surface is partially smeared (part of the adhesive) It is preferable to form an unpainted state. In order to prevent a decrease in air permeability as much as possible and to develop appropriate bonding strength, the coating amount of the hot melt pressure-sensitive adhesive is preferably ³ to 30 g / m ² , particularly 5 to 20 g / m ² .

In order to make the ventilation resistance value of the absorbent body 4 having the web 4a equal to or less than the above-described value, for example, the basis weight and thickness of the long fibers in the web 4a and the basis weight of the superabsorbent polymer may be appropriately adjusted. . Regarding the basis weight of the web 4a, the inventors have found that a range of 5 to 200 g / m ² , particularly 10 to 100 g / m ² is suitable. On the other hand, it has been found that the application basis weight of the superabsorbent polymer is preferably in the range of 50 to 500 g / m ² , particularly in the range of 100 to 300 g / m ² .

The total basis weight of the web 4a and the superabsorbent polymer 4b in the absorbent body 4 is preferably 55 to 700 g / m ² , particularly 110 to 400 g / m ² .

Furthermore, for example, a coating pattern and a coating amount of a hot melt pressure-sensitive adhesive for bonding various members constituting the absorber have an influence on the ventilation resistance value of the absorber. From the viewpoint of more smoothly releasing water vapor, it is preferable to apply a hot melt pressure-sensitive adhesive in a pattern such as bead coating, spiral coating, or spray coating to prevent a decrease in air permeability as much as possible. In order to prevent a decrease in air permeability as much as possible and to develop an appropriate bonding strength, the coating amount of the hot melt pressure-sensitive adhesive is preferably ³ to 30 g / m ² , particularly 5 to 20 g / m ² .

  Factors that affect the airflow resistance of the absorber include the effects of the thickness and density of the absorber in addition to those related to the above hot melt pressure-sensitive adhesive. For example, it is necessary to use the same amount of fluff pulp as the amount of the superabsorbent polymer in order to support the superabsorbent polymer in the opened flap pulp without making the absorber extremely hard. is there. Therefore, the higher the absorption performance, the greater the thickness of the absorber, and as a result, the ventilation resistance of the absorber increases. If the amount of fluff pulp used is reduced to reduce the thickness of the absorber, the absorber must be compressed to maintain the supportability of the superabsorbent polymer. Since the density increases, the ventilation resistance of the absorber increases.

  When the superabsorbent polymer is stably held in the space formed by the crimped long fibers, a large amount of the superabsorbent polymer can be held on the web 4a. In conventional absorbers, it was possible to retain a large amount of superabsorbent polymer by increasing the amount of fiber material such as fluff pulp, but in that case the basis weight and thickness of the absorber increased. End up. Moreover, the air permeability is also lowered. On the other hand, in the absorbent body 4 of the present embodiment, the amount of the superabsorbent polymer is relatively large with respect to the amount of the fiber material. Specifically, the basis weight of the superabsorbent polymer 4b is preferably not less than the basis weight of the web 4a, more preferably not less than 2 times, more preferably not less than 3 times when viewed from the whole absorbent body. ing. Thereby, the air permeability of the absorbent body 4 is increased, and the thickness and the basis weight are reduced. The upper limit of the ratio of the basis weight of the superabsorbent polymer 4b to the basis weight of the web 4a is determined mainly from the viewpoint of extreme movement of the superabsorbent polymer and prevention of falling off. Although depending on the degree of crimp of the long fibers, if the upper limit is about 10 times, the superabsorbent polymer is unlikely to move or drop out even if the wearer performs a violent operation.

  As an evaluation method to the extent that the superabsorbent polymer is buried and supported, the following drop-off evaluation test method can be used. The longitudinal direction center part of the absorber 4 produced to 100 mm x 200 mm is cut | disconnected over the width direction, and a 100 mm x 100 mm test piece is obtained. This cut surface is directly below, and vibration is applied to the left and right 20 times at a speed of once / second with an amplitude of 5 cm. The weight of the polymer that has fallen off from the cut surface is measured. When the weight of the dropped superabsorbent polymer is 25 wt% or less, particularly 20 wt% or less, especially 10 wt% or less, based on the total amount of the superabsorbent polymer present in the test piece, It can be said that this is a state in which the extreme movement and dropout of the functional polymer are difficult to occur.

As an evaluation of the extent to which the superabsorbent polymer is buried and supported, a mobility measured by the following method can be employed in addition to the above-described dropout evaluation test. First, an initial weight W0 of a 100 mm × 100 mm measurement sample used for the measurement of the drop-off evaluation test is measured in advance. The measurement sample after the measurement of the drop-off evaluation test is finished is cut in a direction perpendicular to the direction in which the long fibers extend, and is divided into two equal parts. The weight of each of the two halves divided into two is measured, and the weight of the halved fragment having the larger variation from 1/2 of the initial weight W0 of the measurement sample is adopted as the weight W1 for calculating the transfer rate. To do. For example, assuming that the weights of two fractional pieces are W1 ′ and W1 ″, if these W1 ′ and W1 ″ satisfy the following expression, W1 = W1 ′.
| W1'-W0 / 2 |> | W1 "-W0 / 2 |
Using the value of W1 determined in this way and the value of the initial weight W0 of the measurement sample, the movement rate is calculated from the following equation.
Movement rate (%) = {1-W1 / (W0 / 2)} × 100
When the value of the migration rate thus measured is 40% or less, particularly 30% or less, particularly 20% or less, it can be said that the migration of the superabsorbent polymer is difficult to occur.

  In a simple manner, the following evaluation method can be performed on the test piece subjected to the above-described drop-off evaluation test. 50 g of physiological saline (0.9 wt% NaCl) is evenly sprayed on the test piece subjected to the test for dropout evaluation, and the way of swelling of the test piece is visually observed. When the variation in the thickness of the test piece is within 2 times, it can be said that it is difficult for the superabsorbent polymer to move or drop off.

  In each of the evaluation methods described above, when the web is viewed in the horizontal direction, the test piece is sampled from a region where the superabsorbent polymer is dispersed with the same basis weight.

  When the superabsorbent polymer is not sufficiently embedded in the web, hot melt, various binders (such as acrylic emulsion adhesives), sugar derivatives such as carboxymethylcellulose and ethylcellulose, thermoplastic resins such as polyethylene and polypropylene, etc. Can be appropriately added to the web. Further, the web may be subjected to uneven processing, or a sheet having flocking may be used in combination with the web. When the long fiber is dissolved in a solvent or can be plasticized, an appropriate solvent may be used. For example, when the long fiber contains acetate, a bonding point can be formed on a part of the web by adding triacetin. The formation of the bonding point not only improves the embedding supportability of the superabsorbent polymer, but can also give rigidity to the web by appropriately selecting the addition amount and the processing method, and prevent the twisting and the like from being damaged. it can. Furthermore, imparting an appropriate rigidity gives the user better handleability, and further has the effect of preventing the diaper from shrinking due to excessive gathering and preventing the entire diaper from being deformed.

  Since the absorbent body 4 having the web 4a has a sparse structure with large gaps between fibers compared to a conventional absorbent body mainly composed of flap pulp, the absorbent body 4 has good liquid permeability. It is also a thing. Therefore, when the absorption speed of the absorbent body 4 is slow, the liquid may pass through the absorbent body 4 before being absorbed by the superabsorbent polymer 4b, and may not be sufficiently absorbed by the absorbent body 4. From this viewpoint, it is preferable that the superabsorbent polymer 4b included in the web 4a has a sufficiently high absorption rate. As a result, the liquid can be reliably held in the absorber 4. In the technical field, the absorption rate of the superabsorbent polymer 4b is generally expressed by the measured value of the DW method. The absorption rate (ml / (0.3 g · 30 sec)) by the DW method is measured using an apparatus (Demand Wettability Tester) generally known as an apparatus for performing the DW method. Specifically, the superabsorbent polymer to be measured is placed on a polymer spray table (70 mmφ, No. 2 filter paper placed on the glass filter No. 1) with the saline level set at an equal water level. Spray 0.3g. The amount of water absorption at the time of spraying the superabsorbent polymer is set to 0, and the amount of water absorption after 30 seconds (this absorption amount is measured by a burette scale indicating the amount of decrease in the physiological saline water level) is measured. The value of the obtained absorption amount is taken as the water absorption rate.

  The superabsorbent polymer 4b preferably used in the present embodiment has an absorption rate of 2 to 10 ml / (0.3 g · 30 sec), particularly 4 to 8 ml / (0.3 g · 30 sec) measured according to the DW method. In addition, the superabsorbent polymer having such an absorption rate has been avoided in the conventional absorbent body mainly composed of fluff pulp because it causes gel blocking and consequently liquid leakage. is there. On the contrary, in this embodiment, since the web 4a has a sparse structure, there is no concern about gel blocking even if a high absorption polymer having a high absorption rate is used, and conversely liquid leakage is effective. To be prevented.

In relation to the absorption rate of the superabsorbent polymer, the web 4a preferably has a density of 0.005 to 0.20 g / cm ³ , more preferably 0.01 to 0.10 g / cm ³ . If the density is within this range, the liquid permeation rate in the web 4a can be controlled to an appropriate range commensurate with the absorption rate of the superabsorbent polymer. Moreover, the softness of the absorber can be maintained. Furthermore, the fiber spacing of the web can be set to an appropriate range, and the supporting performance of the fine superabsorbent polymer can be improved.

  The long fibers constituting the web 4 a are preferably oriented in one direction in the plane direction of the absorbent body 4. When the liquid is absorbed in the absorbent body 4 due to the long fibers being oriented in one direction, the liquid is preferentially diffused in the orientation direction of the long fibers. That is, it diffuses preferentially in the planar direction of the absorber. Conversely, diffusion in the direction perpendicular to the orientation direction of the long fibers is suppressed. When the continuous filament is oriented in the longitudinal direction of the diaper 1, liquid leakage (lateral leakage) from the side of the diaper is effectively prevented.

  The degree of orientation of the long fibers is preferably 1.2 or more, particularly 1.4 or more in terms of the degree of orientation. In this embodiment, the degree of orientation is measured using a Microwave molecular orientation analyzer MOA-2001A manufactured by KANZAKI. The sample size is 100 mm in the longitudinal direction and 50 mm in width, and the average value of three points is the degree of orientation. When the sample size is less than this size, measurement is performed by arranging a plurality of samples so as not to overlap each other.

  One means for further preventing side leakage is to use linear long fibers. This is because such a long fiber is superior in liquid diffusibility in the orientation direction of the long fiber as compared to a long fiber having crimps. From this viewpoint, it is preferable that the web 4a is composed of a plurality of layers, and a part of the crimped long fibers in at least one of them is stretched to be in a linear state. When the web 4a has a two-layer structure, a portion of the web on the top sheet side, for example, a crimped long fiber located in the central portion in the longitudinal direction is stretched to be in a linear state so that the excreted liquid can be removed before and after the absorber. It is possible to preferentially guide in the direction. Alternatively, in addition to the crimped long fiber web, the same effect can be obtained by further using a hydrophilic long fiber web having no crimp. For example, a superabsorbent polymer can be sprayed on a crimped long fiber web, and a long fiber web without crimps can be disposed thereon.

  When the long fibers are oriented in the longitudinal direction of the diaper 1, it is preferable that the web 4a does not have a linear bonding line that crosses the orientation direction of the long fibers. When such an adhesive line exists, smooth diffusion of the liquid in the orientation direction of the long fibers is interrupted, which may cause side leakage. On the other hand, when the long fibers are oriented in the width direction of the diaper 1, diffusion in the longitudinal direction of the diaper 1 is suppressed, and spot absorbability is obtained. In this case, in order to prevent liquid leakage (lateral leakage) from the side, the web 4a preferably has a linear bonding line that crosses the orientation direction of the long fibers. “Linear” means a continuous line that suppresses permeation of liquid, and it is not necessary that individual seal lines and the like are continuous without interruption. For example, if the liquid movement can be prevented by arranging the intermittent seal lines in layers, it is linear. In addition to the linear shape, the linear shape may be a curved shape or a broken line shape. The width of the line is preferably about 0.2 to 15 mm.

  The absorber 4 is desirably flexible. In the case of adopting a measured value by a handle-ometer as an evaluation of flexibility, the measured value is preferably 4N or less, particularly 2N or less. The measurement method using the handle-o-meter is as follows. Measurement is performed according to JIS L1096 (flexibility measurement method). The absorbent body 4 cut in the longitudinal direction by 150 mm and in the width direction by 50 mm is arranged in a direction perpendicular to the grooves on a support base having a groove having a width of 60 mm. The force required when the center of the absorber 4 is pushed by a blade having a thickness of 2 mm is measured. The apparatus used in the present embodiment is a texture testing machine (handle-of-meter method), HOM-3 type, manufactured by Daiei Scientific Instruments. The average value of the three points is taken as the measured value.

  The absorbent body 4 according to the present embodiment may be composed only of the web 4a and the superabsorbent polymer 4b, or these may be made of paper or non-woven fabric such as tissue paper (hereinafter also referred to as a covering sheet). It may be wrapped. Further, a dry pulp sheet or a fluff pulp layer may be disposed on the upper surface and / or the lower surface of the web 4a and the superabsorbent polymer 4b, and the whole may be wrapped with a covering sheet. . Regardless of the form of the absorber 4, the ventilation resistance value is set to be equal to or less than the value described above. Moreover, it is preferable from the point of ensuring sufficient air permeability that the thickness of the absorber 4 is 1-4 mm, especially a thin thing of 1.5-3 mm.

  The absorbent body 4 and the covering sheet that wraps the absorbent body 4 include other particles such as activated carbon, silica, alumina, titanium oxide, various viscosity minerals (zeolite, sepiolite, bentonite, cancrinite, etc.) in addition to the superabsorbent polymer. ) And other organic and inorganic particles (deodorant and antibacterial agent). As the inorganic particles, those obtained by substituting a part of metal sites can be used. Alternatively, various organic buffers and inorganic buffers, that is, acetic acid, phosphoric acid, citric acid, succinic acid, adipic acid, malic acid, lactic acid and salts thereof alone or in combination, and various amino acids are included. Also good. The function of these components is to suppress the odor of the liquid absorbed by the absorber 4 and the covering sheet and the odor derived from the material. In addition, various organic buffers and inorganic buffers have the effect of neutralizing excrement, for example, ammonia generated by decomposition of urine, and keeping the diaper 1 neutral to weakly acidic. Even if the excrement returns from 4 to the skin, the effect on the skin is reduced. When a fiber having an ester bond in a molecular structure such as an acetate fiber is used as the long fiber constituting the web, an effect of preventing the fiber from being damaged due to the decomposition of the ester bond by alkali can be expected.

  In addition, hydrophilic fine powder or short fibers can coexist in the web for the purpose of improving liquid retention and absorption rate and improving dryness. Hydrophilic fine powders or short fibers include fibrillated or non-fibrillated cellulose powder, carboxymethyl cellulose and its metal salt, carboxyethyl cellulose and its metal salt, hydroxyethyl cellulose and its derivatives, silk powder, nylon powder, Examples include short fibers such as rayon, cotton, and wool. Among these, it is preferable to use cellulose powder because the above effects can be improved to the maximum. The hydrophilic fine powder or short fiber may be sprayed on the web before spraying the superabsorbent polymer, or may be mixed with the superabsorbent polymer and sprayed on the web at the same time.

  Another embodiment of the absorber includes a structure in which a web 4a and a superabsorbent polymer 4b are stacked on a fluff pulp stacking layer. In this absorber, a superabsorbent polymer is embedded and supported in the web 4a. In this absorbent body, the fluff pulp fiber layer acts as a primary stock layer of excreted liquid, so even if the liquid excretion rate is high (for example, when urine is excreted), liquid leakage is prevented. It can be effectively prevented.

  As still another embodiment of the absorbent body, there is a structure in which a plurality of stacked fiber bodies having a structure in which a web 4a and a superabsorbent polymer 4b are stacked on a fluff pulp stacked fiber layer. A superabsorbent polymer may be mixed in the fluff pulp stacking layer. In the absorbent body having this structure, the effect as a primary stock layer of the liquid by the fluff pulp pile layer is further enhanced as compared with the absorbent body of the embodiment described above.

  As still another embodiment of the absorbent body, a second web of hydrophilic long fibers not containing the superabsorbent polymer is disposed on the upper and / or lower side of the web 4a in which the superabsorbent polymer is embedded and supported. The thing of the made structure is mentioned. When the long fibers contained in the second web are crimped, particularly when having the above-described crimp rate, the second web acts as a cushion layer against pressing in the thickness direction. Therefore, the wearing feeling of the absorbent article is improved. In addition, the air permeability is further improved by increasing the space in the absorber. Furthermore, since it has an excellent compression recovery property, it is thin when compressed in a packaging bag packed with a plurality of diapers, and the thickness is quickly recovered when taken out from the packaging bag.

As for the compression recovery property of the absorber part from which the influence of gathers has been removed, the value at least one hour after releasing the pressure is preferably 1.2 times or more, more preferably 1.5 times or more of the initial thickness. The initial thickness of the absorber is measured after applying a load of 250 g / cm ² in advance for 12 hours. The thickness is measured in a state where five samples are stacked. The value obtained by dividing the measured value by 5 is the thickness per sheet. The measurement is performed under a state where a weight is placed on an acrylic plate having a size of 5 cm × 5 cm and a load of 2.5 g / cm ² is applied. The apparatus uses a KEYENCE LK080 class 2 laser displacement meter. 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.

The absorber of each of the embodiments described above is thin, flexible, and has an appropriate structural stability. Appropriate values are selected for the thickness and basis weight of the absorbent according to the specific application of the absorbent article. When an absorber is used for a disposable diaper, it is preferable that the thickness is 0.5 to 4 mm, especially 1 to 3 mm, regardless of the shape of the absorber. The thickness of the absorber is measured under a state where a weight is placed on an acrylic plate having a size of 5 cm × 5 cm on the absorber 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.

  In order to further improve the air permeability of the absorber of each of the above embodiments, an opening may be provided in a part of the absorber. Since the absorbent body of each embodiment is thin, the opening process is easier than the conventional thick absorbent body. Or you may form a groove | channel between each small piece by forming the absorber of each above embodiment from a several small piece. In this case, the web may exist in a continuous state between each piece, or may exist discontinuously.

  Next, second and third embodiments of the present invention will be described with reference to FIGS. Regarding points that are not particularly described in the second and third embodiments, the description in detail regarding the first embodiment is appropriately applied. 3 to 7, the same members as those in FIGS. 1 and 2 are denoted by the same reference numerals.

  The diaper 1 of the embodiment shown in FIG. 3 has two pairs of a pair of opposing three-dimensional gathers. In the diaper 1, leg gathers 7 are formed by extending leg elastic members 71 extending in the longitudinal direction of the diaper 1 on the side edges of the leg fluff L extending laterally from the side edges of the absorbent body 4. In addition, a first three-dimensional gather 61 and a second three-dimensional gather 62 having a base end portion are disposed between the leg gather 7 and the side edge of the absorber 4. The first three-dimensional gather 61 is arranged near the leg gathers, and the second three-dimensional gather 62 is arranged near the absorber.

  These three gathers located in the leg flap L adjust the shrinkage force of each gather so that the shrinkage force of the outermost gather is larger than the shrinkage force of the gathers located inward. It is preferable. That is, when the contraction force of the leg gather 7 is L1, the contraction force of the first three-dimensional gather 61 is L2, and the contraction force of the second three-dimensional gather 62 is L3, it is preferable that L1> L2, L3. In particular, it is preferable that the gather contraction force gradually decreases from the outermost gather to the inside. That is, it is preferable that L1> L2> L3. The reason is as follows.

  The conventional design method for absorbent articles is to reduce the thickness of the absorbent article and make it difficult to leak liquids, thereby increasing the shrinkage force of gathers and leaving a gap between the wearer's body and the absorbent article. Based on the idea of not. However, if the contraction force of the gathers is too strong, the marks are likely to touch the skin. In addition, when the thin and flexible or absorbent body is used as in the present invention, the absorbent article contracts due to the contraction force of the gathers, making it difficult to wear. If the gather contraction force is too strong, a downward force due to the contraction force acts on the absorbent article during mounting of the absorbent article, and a shift tends to occur. On the other hand, by using two or more sets of leg gathers and a pair of opposing three-dimensional gathers and having the contraction force as described above, the above-described inconveniences that occur in conventional absorbent articles can be avoided.

  The gather contraction force is measured by the following method. A gather is cut from the absorbent article and used as a measurement sample. A hysteresis curve of the measurement sample is drawn using Tensilon ORIENTEC RTC-1150A. The stress at the return of this hysteresis curve is defined as the contraction force. The speed of pulling and returning is 300 mm / min. The initial length of the sample is 100 mm, and the maximum elongation is 100 mm (twice the original length). The stress at the time of return of the hysteresis curve is a measured value when the sample is returned 50 mm from the maximum elongation. The measurement is an average of 5 points. In the case of a sample whose maximum elongation is less than 100 mm, the elongation is up to 50 mm, and the value at that time is the measured value.

  In order to adjust the contraction force of each gather, for example, methods such as changing the thickness of the elastic member, changing the expansion rate of the elastic member, changing the number of elastic members, etc. are used alone or in combination. Moreover, it is preferable that the stretchable area of the leg gathers 7 is only the crotch part of the absorbent article. Here, the crotch portion refers to a region in which both side edges of the product center portion are curved so as to be along the legs.

  In the diaper 1 shown in FIG. 3, two sets of leg gathers and a pair of opposing three-dimensional gathers are used. Instead of using leg gathers, two or more pairs of opposing solid gathers may be used. For example, in FIG. 4, two sets of three-dimensional gathers, that is, a first three-dimensional gather 61 and a second three-dimensional gather 62 are used. Also in this case, it is preferable for the same reason as described above to gradually reduce the contraction force of the three-dimensional gathers from the outer side in the width direction of the diaper 1 to the inner side.

  Next, a third embodiment will be described. As described above, according to the absorbent article of the present invention including the absorbent body using the long fiber web, it is possible to suppress an increase in humidity in the wearing. The effect of suppressing this increase in humidity is more pronounced for absorbent articles with better fit to the wearer's body. The third embodiment relates to such a pants-type disposable diaper having good fit to the wearer's body.

In order to further improve the fit to the wearer's body, in the present embodiment, a diaper is produced using the following design method.
First step: Apply a sheeting (a cloth having sufficient dimensions compared to the planar shape of the absorbent article) directly to the body of the monitor (such as an infant), and by draping around the waist of the monitor and at the root of the thigh The line around the thigh root (the thigh root circumference in FIG. 5) and each side line are written, and the obtained pattern is used as a base pattern for the planar shape design. This base pattern is taken into CAD, and the subsequent correction process is performed. FIG. 6A shows a base pattern obtained by transferring the body shape in this way. The vertical line segment La in the figure is the distance from the umbilical point of the monitor to the first lumbar vertebra [see FIG. The horizontal line segment Lb orthogonal to the vertical line segment indicates the position in the front-rear direction where the distance between the lines around the left and right thigh roots is minimum (corresponding to the position in the front-rear direction where the crotch width of the monitor is minimum) And its minimum distance. A curve Lc indicates a line around the thigh root, a curve Ld indicates a line around the waist passing through the umbilicus and the first lumbar vertebra, and a curve Le indicates a line on the side of the monitor (on the left and right sides of the monitor). (Ridge line). In this way, a base pattern for a plurality of monitors is obtained.

  Second step: For each base pattern, corrections according to certain rules are made to correct the left and right non-uniformities. For example, the length and positional relationship of the vertical line segment La and the horizontal line segment Lb, and the shape and length of the more reliable one of the curved lines Lc existing on the left and right sides of the vertical line segment La are not corrected. The lower reliability of Lc is replaced with a curved line Lc ′ in which the higher reliability is copied symmetrically with respect to the vertical line segment La. For the curved line Le, each end of the base pattern in the longitudinal direction is replaced. In FIG. 5, the longer shape and length of the left and right are unified to the shorter shape and length. The curve Ld is divided into front, rear, left and right portions of the base pattern, and these are unified into an averaged shape. FIG. 6B shows a corrected base pattern that has been corrected in this way.

  Third step: The corrected base pattern is divided into a plurality of groups according to the age of the monitor (monthly), gender, etc., and averaged for each category to obtain a master pattern. All corrected base patterns can be averaged together and used as a master pattern.

  Fourth step: The monitor is allowed to act freely, and the behavior is recorded on a video and observed. The actions frequently performed by the monitor and how the wearer's skin expands and contracts during these actions is determined. As a result of observing and analyzing the behavior of infants, monthly infants using pants-type absorbent articles (especially pants-type diapers) lean forward and lean from standing to sitting or vice versa. In the heel movement, the back surface and the thigh root part, in the standing to sitting position or vice versa, in addition to the back surface, the waist part in the ventral side, the movement that leans forward in the sitting position It was found that the skin at the base of the thigh frequently expands and contracts when running around the back.

  Fifth step: A correction reflecting the knowledge of skin expansion and contraction obtained in the fourth step is added to each master pattern (or a single master pattern) obtained in the third step. This correction is performed in order to ensure an area that can be expanded and contracted following the expansion and contraction of the skin. FIG. 6 (c) shows a lattice pattern on the master pattern in order to secure the disposable absorbent article with a stretchable region that follows the stretch of the skin on the back of the wearer and the stretch of the skin at the thigh root portion. The correction master pattern obtained by adding the area is shown. The region following the skin expansion and contraction of the waistline portion on the abdominal side is included in the region for imparting ease (ease of wearing) to be applied in the next step, and is omitted here.

  Sixth step: A correction is applied to the correction master pattern to give ease (mounting ease). FIG. 6D is a diagram showing a pattern obtained by enlarging the corrected master pattern at a predetermined magnification in the width direction. The pattern obtained by this correction is the final pattern that becomes the planar shape of the diaper.

  Seventh step: How to dispose the elastic member with respect to the final pattern is determined in consideration of the expansion and contraction of the skin obtained in the fourth step. In the arrangement of the elastic member, the elastic member is arranged so as to form a region that can elastically expand and contract following the expansion and contraction of the skin, and the elastic member is arranged based on a conventional viewpoint such as leakage prevention. And design of a disposable absorbent article is completed by determining arrangement | positioning etc. of a required member.

  In the pants-type disposable diaper designed based on the above design method, the fit to the wearer's body is extremely high by having any one or more of the following requirements (a) to (e). Become good. The combination of two or more requirements is a combination of any one of the following requirements (a) to (e) with the other [hereinafter referred to as combination (1). For example, (a) + (b), (a) + (c), (a) + (d), (a) + (e), (b) + (c), (b) + (d), ( b) + (e), (c) + (d), (c) + (e), (d) + (e), etc.), a combination of combination (1) and another requirement (hereinafter, (Combination (2)), combination (2) with one more requirement (hereinafter referred to as combination (3)), combination (3) with one more requirement, etc. Can do.

<Requirements>
(a); waist elastic members are disposed along the circumferential direction of the waist opening at the waist portions of the ventral side portion and the back side portion, and both waist portions are stretched to the maximum in the absorbent article width direction. The tensile load when it is extended to 50% of 2 to 5 N.
(b): Can be expanded and contracted in a direction inclined to the back side by 45 degrees with respect to the longitudinal direction of the absorbent article on both side portions located outward in the width direction from the positions of both side edges of the absorbent body in the waist part of the ventral side It has an elastic elastic part. It is preferable that the tensile load when the both waist portions of the abdominal side and the back side are extended to 50% of the maximum extension rate in the diaper width direction is 1 N or less.
(c); an elastic expansion / contraction part that expands and contracts in the longitudinal direction of the absorbent article between the absorbent body on the back side and the peripheral edge of the waist opening (the longitudinal edge in the case of a deployable disposable absorbent article); Have. In this case, it is preferable that the peripheral edge of the waist opening in the back side is formed in a convex shape.
(d); The waist elastic member is disposed so as to be positioned above the wearer's iliac spine when the absorbent article is worn.
(e) An elastic stretchable portion that can be stretched in the vertical direction with respect to the peripheral edge of the leg opening portion in the back side portion is provided in the vicinity of the leg opening portion in the back side portion. In this case, it is preferable that the peripheral edge of the leg opening in the back side is curved convexly toward the center of the opening of the leg opening.

  The pants-type disposable diaper designed based on the design method described above realizes difficulty in slipping and fit to the body without strongly tightening the body.

  The unfolded state of the pants-type disposable diaper of this embodiment is shown in FIG. For tightening the body with the diaper 100 shown in FIG. 7, the tensile load when the both waist portions D, D are extended to 50% of the maximum extension rate in the diaper width direction is 2 to 5 N, especially 3 It is preferably ˜4N. The tensile load when stretched to 50% of the maximum stretch rate is measured as follows.

[Measurement method of tensile load at both waists]
Both waist parts are cut out from the diaper in a ring-like state in which both are connected, and this is used as a sample. This sample is placed on a horizontal surface so that the outer surface of either one of the waist portions is in contact with the horizontal surface, and between both ends of the sample in a naturally contracted state ( The length between the left and right side joints 23) is measured and set as the initial length. Then, the sample is fixed between chucks of a Tensilon tensile tester [manufactured by Orientec Co., Ltd., “RTC-1150A”] and stretched in the same direction as the diaper width direction at a speed of 300 mm / min. From the initial length, the design dimensions shown in FIG. 7 (same as the dimensions when flattened in a state in which the influence of the elastic member is completely eliminated, except that the waist portion is formed between the ventral portion A and the dorsal portion B. If the design dimensions are different from each other, the average value thereof) is defined as the maximum expansion ratio (expanded length−initial length) / initial length × 100), and 50% of the maximum expansion ratio. Obtain the tensile load when stretched to the stretch rate of.

Further, the tensile load when the waist portions E and E (see FIG. 7) of the abdominal side and the back side are extended to 50% of the maximum extension rate in the diaper width direction is 1 N or less. The said tensile load of both waist parts is measured as follows.
[Measurement method of tensile load on both waists]
Both waistline parts are cut out from the diaper in a ring-like state in which both are connected, and this is used as a sample. This sample is placed on a horizontal surface so that the outer surface of one of the waist portions of both waist portions is in contact with the horizontal surface, and between the both ends of the sample in a naturally contracted state ( The length between the left and right side joints) is measured to obtain the initial length. Then, the sample is fixed between chucks of a Tensilon tensile tester [manufactured by Orientec Co., Ltd., “RTC-1150A”] and stretched in the same direction as the diaper width direction at a speed of 300 mm / min. From the initial length, the design dimensions shown in FIG. 7 are the same as the dimensions when the sample is expanded in a flat shape without any influence of the elastic member (however, the waist part is the ventral part A and the back part B). If the design dimensions are different from each other, the average value thereof) is defined as the maximum expansion ratio (expanded length−initial length) / initial length × 100), and 50% of the maximum expansion ratio. Read the tensile load when stretched to the stretch rate of.

A prototype having the same configuration as that of the present embodiment was prepared, and a pressure sensor was inserted between the waist part E of the abdominal side A and the wearer's skin when worn, and the pressing force against the skin was measured. / Cm ² or less, and it was confirmed that the degree of tightening was extremely small compared to conventional pants-type diapers with gathers around the waist (7 g / cm ² or more).

  In the diaper 100 shown in FIG. 7, the ratio of the circumference of the waist opening at the maximum extension to the circumference of the waist opening in the natural state is preferably 1.4 to 2.2, and more preferably 1.6. ~ 2.0. The waist elastic member 101 in the ventral part A and the dorsal part B is positioned above the wearer's iliac spine point (the height position of the wearer's iliac spine point in an upright state) when the diaper is worn. It is arranged in.

  A leg elastic member 102 is disposed along the circumferential direction of the opening periphery of each leg opening. Moreover, the elastic expansion-contraction part which shrink | contracts in a diaper width direction is formed in the site | part of the width direction outer side from the position of the both-sides edge 104,104 of the absorber 103 in the waist part E. As shown in FIG. The waistline elastic member 105 that forms the elastic expansion / contraction portion is divided and arranged on the left and right sides of a portion overlapping the absorber 103, but the left and right waistline elastic members 105 are continuous across the portion overlapping the absorber 103. You may do it.

  As shown in FIG. 7, the peripheral edge 106 of the leg opening in the back side portion B is convexly curved toward the center of the opening of the leg opening.

  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, the present invention can be applied to a disposable diaper having a side panel as described in the section of the prior art. Since disposable diapers having side panels generally tend to adhere to the wearer's body, the humidity in the clothing tends to increase. Therefore, applying the present invention to such a diaper increases the humidity in the clothing. It is effective from the point of suppressing.

  When the present invention is applied to a disposable diaper having a side panel, the shape of the side panel is desirably designed based on the design method described above. The stretchable material constituting the side panel is typically a composite of an elastomer material and a woven or non-woven fabric, preferably a non-woven fabric. Elastomer materials include polystyrene, isoprene or polybutadiene block copolymers (styrene-ethylbutadiene-styrene, styrene-isoprene-styrene), ethylene copolymers, natural rubber, urethane, vinyl acetate-ethylene, ethyl acetate-ethylene, Examples include acrylic acid-ethylene, methyl acrylate-ethylene, and ethylene-propylene copolymer. The elastomeric material is formed into a film or fiber assembly. Examples of the nonwoven fabric include thermal bond nonwoven fabric, spunbond nonwoven fabric, spunbond-meltblown-spunbond nonwoven fabric, spun using fibers solely using thermoplastic resins such as polyethylene, polypropylene, polyethylene terephthalate, or composite fibers thereof. In addition to bond-melt blown-melt blown-spun bond nonwoven fabric, needle punched nonwoven fabric, spunlace nonwoven fabric and the like can be mentioned. As a method for imparting stretchability to a composite material of an elastomer material and a nonwoven fabric, a method of subjecting the nonwoven fabric to slit processing or some kind of crushing treatment after combining the elastomer and the nonwoven fabric under non-extension, or a stretched state in advance And a method of combining a non-woven fabric with the elastomer described above. It is desirable that the stretch material produced using any material and method has air permeability.

  Moreover, this invention is not restricted to a disposable diaper, It can apply similarly to other absorbent articles, for example, various sanitary napkins, an incontinence pad, etc. In particular, application to wear-type absorbent articles such as shorts-type napkins is effective.

[Example 1]
First, a crimped acetate long fiber tow was prepared. The fiber diameter of this long fiber was 2.1 dtex, and the total fiber amount of tow was 25,000 dtex. The tow was opened using an air opening device under elongation to obtain a spread web. Further, the web was wound by passing a spread web between a roll in which a large number of disks were incorporated around the axis at predetermined intervals and a smooth receiving roll. Thereafter, the web was adjusted to a width of 100 mm, transferred to a vacuum conveyor in a state where the conveyance speed was reduced, and the web tension on the vacuum conveyor was relaxed to develop crimps. The crimp rate of the long fibers in the web was 30%, and the number of crimps per 1 cm was 15. As a result, the space between the long fibers was widened to facilitate the entry of the superabsorbent polymer, and the web was thickened to improve the embedding supportability of the superabsorbent polymer. A superabsorbent polymer of 130 g / m ² was sprayed on the web to obtain a first web p1 in which particles of the polymer were embedded and supported in the spread web. Thereafter, the same operation as this operation was repeated once more to obtain a second web p2 composed of a web in which particles of superabsorbent polymer were embedded and supported. A fluff pulp layer having a basis weight of 50 g / m ² was sandwiched between the first web p1 and the second web p2 thus obtained.

Further, a fluff pulp layer having a basis weight of 100 g / m ² was disposed under the second web p2. Their entirety, wrapped in tissue paper of the hot melt adhesive basis weight 16g / m ² of a 5 g / m ² was spray coating, to obtain an absorbent. In the absorbent body, a fluff pulp layer having a basis weight of 100 g / m ² is located on the side farthest from the skin. The basis weight of the entire absorber was 502 g / m ² and the thickness was 2.2 mm. The basis weight of each spread web was 13 g / m ² .

An air-through nonwoven fabric having a basis weight of 25 g / m ² was used as the surface sheet. The surface sheet was subjected to a hole opening treatment with a metal pin having a diameter of 5 mm. The air-through nonwoven fabric was composed of a core-sheath type composite fiber (thickness: 2.1 dtex, surface treatment with a surfactant and liquid permeability) having a core made of polypropylene and a sheath made of linear low density polyethylene. A porous film having a basis weight of 20 g / m ² as a backsheet, used was composite by bonding a polypropylene spunbond nonwoven fabric having a basis weight of 20 g / m ² hot melt 1.5 g / m ^2. The porous film is obtained by uniformly forming 100 parts by weight of a linear low density polyethylene resin having a density of 0.925 g / cm ³ , 150 parts by weight of calcium carbonate, and 4 parts by weight of an ester compound as a third component. The film was uniaxially stretched twice in the longitudinal direction. Other than that, according to the manufacturing method of a normal disposable diaper, the disposable diaper of the structure shown in FIG.1 and FIG.2 was obtained. The absorber was arranged so that the orientation direction of the web coincided with the longitudinal direction of the diaper.

[Example 2]
A web p1 in which particles of a superabsorbent polymer were embedded and supported in a spread web was obtained in the same manner as in Example 1 except that the scattering basis weight of the superabsorbent polymer was 110 g / m ² . Next, 100 parts by weight of the opened fluff pulp and 100 parts by weight of the superabsorbent polymer were uniformly mixed in an air stream to obtain a mixture m having a total basis weight of 300 g / m ² . The basis weights of fluff pulp and superabsorbent polymer in the mixture were 150 g / m ² , respectively. The mixture m was overlapped on the web p1, and these were wrapped using a spunbond-meltblown-spunbond nonwoven fabric (SMS) having a basis weight of 16 g / m ² obtained by hydrophilization to obtain an absorbent body. The basis weight of the entire absorbent body was 482 g / m ² and the thickness was 2 mm. Other than that was carried out similarly to Example 1, and obtained the disposable diaper.

Example 3
In Example 2, an absorbent body was obtained in the same manner as in Example 2 except that the laminate of the web p1 and the mixture m was subjected to a hole opening treatment using a metal pin having a diameter of 5 mm. The opening was formed with a length of 200 mm and a width of 50 mm starting from a position of 100 mm from the front end of the absorber. The metal pins that are adjacent to each other in the width direction have an interval of 1 cm, the front and rear are arranged in a staggered pattern, and the front and rear metal pins have an interval of 1 cm. The disposable diaper was obtained like Example 2 using the obtained absorber.

Example 4
With respect to the web of Example 1, the basis weight of the superabsorbent polymer was set to 110 g / m ² , and the superabsorbent polymer was embedded and supported in the spread web. Next, 100 parts by weight of the opened fluff pulp and 100 parts by weight of the superabsorbent polymer are uniformly mixed in an air stream and stacked on a T-shaped mold, and the total basis weight is 300 g / m ² . Got the body. The T-shaped mold had a leg width of 100 mm, a length of 100 mm, a horizontal frame width of 125 mm, and a length of 100 mm. The basis weights of the fluff pulp and the superabsorbent polymer in the piled body were 150 g / m ² , respectively. The web was stacked on the piled fiber, and the whole was wrapped with a tissue paper having a basis weight of 16 g / m ² and spray-coated with a hot melt adhesive to obtain an absorbent. Other than that was carried out similarly to Example 1, and obtained the disposable diaper.

Example 5
In Example 4, the fiber diameter of the long fibers was 6.7 dtex, the total fiber amount of the tow was 17,000 dtex, the crimp rate of the long fibers in the web was 24%, and the number of crimps per cm was 10 pieces. Yes, a laminate was obtained in the same manner as in Example 4 except that the average basis weight of the web was 30 g / m ² . Other than that was carried out similarly to Example 4, and obtained the disposable diaper.

[Comparative Example 1]
100 parts by weight of the opened fluff pulp and 100 parts by weight of the superabsorbent polymer were uniformly mixed in an air stream to obtain a mixture having a total basis weight of 520 g / m ² . The basis weights of the fluff pulp and the superabsorbent polymer were 260 g / m ² , respectively. The obtained mixture was wrapped with a tissue paper having a basis weight of 16 g / m ² to obtain an absorbent. Between the mixture and tissue paper, 5 g / m ² of hot melt pressure-sensitive adhesive was spray-coated and adhered. The basis weight of the entire absorbent body was 562 g / m ² and the thickness was 4.3 mm. Except these, it carried out similarly to Example 1, and obtained the disposable diaper.

[Comparative Example 2]
As in Comparative Example 1, 100 parts by weight of the opened fluff pulp and 100 parts by weight of the superabsorbent polymer were uniformly mixed in an air stream to obtain a mixture having a total basis weight of 300 g / m ² . The basis weights of the fluff pulp and the superabsorbent polymer were 150 g / m ² , respectively. Other than that was carried out similarly to the comparative example 1, and obtained the absorber. The basis weight of the entire absorbent body was 342 g / m ² and the thickness was 2.6 mm. A disposable diaper was obtained in the same manner as in Comparative Example 1 except that this absorber was used.

[Comparative Example 3]
In the same manner as in Comparative Example 1, 100 parts by weight of the opened fluff pulp and 100 parts by weight of the superabsorbent polymer were uniformly mixed in an air stream to obtain a mixture having a total basis weight of 400 g / m ² . The basis weights of the fluff pulp and the superabsorbent polymer were 200 g / m ² , respectively. Other than that was carried out similarly to the comparative example 1, and obtained the absorber. The basis weight of the entire absorbent body was 442 g / m ² and the thickness was 3.0 mm. A disposable diaper was obtained in the same manner as in Comparative Example 1 except that this absorber was used.

[Comparative Example 4]
Similarly to Comparative Example 1, 100 parts by weight of the opened fluff pulp and 100 parts by weight of the superabsorbent polymer were uniformly mixed in an air stream to obtain a mixture having a total basis weight of 200 g / m ² . The basis weights of the fluff pulp and the superabsorbent polymer were 100 g / m ² , respectively. Other than that was carried out similarly to the comparative example 1, and obtained the absorber. The basis weight of the entire absorbent body was 242 g / m ² and the thickness was 1.7 mm. A disposable diaper was obtained in the same manner as in Comparative Example 1 except that this absorber was used.

[Performance evaluation]
About the absorber in the diaper obtained by the Example and the comparative example, the absorption capacity | capacitance and ventilation resistance value were measured with the following method, and the softness | flexibility and structural stability were evaluated. Moreover, fit property was evaluated about the diaper. The results are shown in Table 1 below.

[Absorption capacity]
The obtained absorbent body was fixed to a 45 ° inclined plate, and 40 g of physiological saline was repeatedly injected at intervals of 5 minutes into a position 200 mm from the upper end of the absorbent body. The amount of injection until leakage from the lower end of the absorber was compared. The relative value when the absorption capacity of Comparative Example 1 was 1.0 was calculated using the following formula.
Absorption capacity (relative value) = (absorption capacity of sample) / (absorption capacity of comparative example 1)

(Ventilation resistance value)
The ventilation resistance value of the absorber manufactured to 100 mm x 100 mm was measured using a Kato Tech air permeability tester KES-F8 (trade name). According to this apparatus, the pressure loss when a constant flow rate of air (4 cc square cm / sec) is passed is measured, and the ventilation resistance value is calculated. Measurement was performed at five points, and the average value was taken as the measured value.

[Flexibility]
The absorber was subjected to a handle-ometer test, and the flexibility was evaluated according to the following criteria. The smaller the value, the better the contactability and fit.
○: The measured value of the handle-o-meter is 2N or less.
(Triangle | delta): The measured value of a handle ohm meter exceeds 2N and is 4N or less.
X: The measured value of the handle o meter exceeds 4N.

[Structural stability]
(1) At the time of dry The longitudinal direction center part of the absorber produced to 50 mm x 200 mm was cut | disconnected over the width direction, and the sample of 50 mm x 100 mm was obtained. The amount of polymer dropped from the cut surface was measured when the vibration was applied 20 times at a speed of 1 cm / sec with an amplitude of 5 cm with the cut surface directly below. The structural stability was evaluated according to the following criteria.
Of the mixed superabsorbent polymers,
○: The ratio of the superabsorbent polymer that has dropped off is 10% or less.
(Triangle | delta): The quantity of the superabsorbent polymer which dropped out exceeds 10% and is 25% or less.
X: The amount of the superabsorbent polymer dropped off exceeds 25%. (2) When wet The absorbent body produced 50 mm × 200 mm was absorbed almost uniformly by 100 g of physiological saline, and then the absorbent body was gently lifted. At that time, it was visually determined whether or not the absorber was destroyed. Also, the weight of the dropped superabsorbent polymer was measured, and the weight of the dropped superabsorbent polymer when dried was divided by the centrifugal retention per unit weight of the dropped superabsorbent polymer measured separately. calculate. Furthermore, the ratio of the superabsorbent polymer dropped off from the relationship with the blending amount of the superabsorbent polymer is calculated. The amount of the superabsorbent polymer blended was determined by immersing the absorbent to be analyzed in advance in an ascorbic acid aqueous solution and exposing it to sunlight for a sufficient amount of time to completely decompose the superabsorbent polymer. Let Washing with water and decomposition are repeated, the superabsorbent polymer is completely dissolved and then dried, and the blending amount of the superabsorbent polymer can be estimated from the difference in the weight of the absorber before the decomposition.
○: The ratio of the superabsorbent polymer dropped off is 10% or less, and the absorber is not destroyed.
(Triangle | delta): The ratio of the superabsorbent polymer which dropped out exceeds 10% and is 25% or less, and there is no destruction of an absorber.
X: The ratio of the superabsorbent polymer dropped off exceeds 25%, or the absorber is destroyed.

[Fitness]
The obtained diapers were attached to 5 infants (7 to 14 months) using L size pants diapers, and their mother's impression was heard.
○: It fits neatly and the crotch is not stiff.
Δ: A little clear.
X: There is a feeling of muffledness, it is not refreshing, and it does not fit.

  As is clear from the results shown in Table 1, it can be seen that the absorbent bodies produced in each example have a sufficient absorption capacity and a low ventilation resistance value. Further, it is flexible, and it can be seen that the structure of the absorber is stable both in the dry state and in the wet state. And it turns out that the diaper which has the absorber produced in each Example becomes good fitting property.

Example 6
In this example, the relationship between the crimp rate of the long fiber web and the loading rate of the superabsorbent polymer was examined. The fiber diameter of this long fiber was 2.1 dtex. This long fiber tow was conveyed under elongation and opened using an air opening device to obtain a spread web. Next, the web was wound through a spread web between a roll in which a large number of disks were incorporated around the axis at predetermined intervals and a smooth receiving roll. Thereafter, the web was adjusted to a width of 100 mm, transferred to a vacuum conveyor in a state where the conveyance speed was reduced, and the web tension on the vacuum conveyor was relaxed to develop crimps. The tension of the web was controlled to prepare a web of acetate long fibers having various crimp rates. As a result, the space between the long fibers was widened to facilitate the entry of the superabsorbent polymer, and the web was thickened to improve the embedding supportability of the superabsorbent polymer. A superabsorbent polymer was sprayed on the web, and the superabsorbent polymer was buried and supported in the spread web. The basis weight of the web was 26 g / m ² . The spreading basis weight of the polymer was 260 g / m ² . As the polymer, a bulk type having an average particle size of 330 μm was used. The above-described structural stability (when dry) test was performed on the absorbent body thus obtained. The weight of the superabsorbent polymer supported on the web after the test is divided by the weight of the superabsorbent polymer blended in the web before the test and multiplied by 100, and the obtained value is multiplied by the superabsorbent polymer. The loading ratio (%). The results are shown in Table 2.

It is a perspective view which shows the disposable diaper as one Embodiment of the absorbent article of this invention. It is the II-II sectional view taken on the line in FIG. It is a schematic diagram which shows the width direction cross section of the crotch part in the disposable diaper as 2nd Embodiment of the absorbent article of this invention. It is a schematic diagram which shows the width direction cross section of the crotch part in the disposable diaper as another embodiment of the absorbent article of this invention. It is a figure which shows the measurement site | part etc. in the novel design method of a disposable diaper. It is a figure for demonstrating the novel design method of a disposable diaper, (a) is a figure which shows the base pattern obtained by transcribe | transferring a body shape, (b) is the correction which added correction to the base pattern It is a figure which shows a base pattern, (c) is a figure which shows the correction master pattern which considered the expansion and contraction of a wearer's skin, and added the correction to the master pattern, (d) is a figure which shows a correction master pattern. FIG. 10 is a diagram showing a final pattern obtained by making corrections in consideration of ease of wearing (ease of wearing) and the like. It is a top view which shows the expansion | deployment and expansion | extension state of the disposable diaper as the 3rd Embodiment of this invention.

Explanation of symbols

1 disposable diaper (absorbent article)
2 Top sheet 3 Back sheet 4 Absorber 4a Web 4b Superabsorbent polymer 5 Exterior sheet 6 Solid gather 7 Leg gather L Leg flap W Waist flap

Claims (7)

Comprising an absorbent body comprising a hydrophilic long fiber web and a superabsorbent polymer;
The long fibers constituting the web are oriented in one direction in the plane direction of the absorber,
The long fibers are crimped, and the long fibers are not bonded to each other in the web,
The superabsorbent polymer is a lump, and the lump-like superabsorbent polymer is embedded and supported in a network structure formed on the web;
The basis weight of the superabsorbent polymer is not less than the basis weight of the web and not more than 20 times, and the ventilation resistance value of the absorber per 100 g / m ^{2 of the} superabsorbent polymer is 0.25 kPa · s / Absorbent article which became m or less.   Leg flaps extending in the longitudinal direction are formed at positions outward in the width direction from the left and right side edges of the absorber, and one or more elastic members extending in the longitudinal direction are arranged on the leg flaps. The absorbent article according to claim 1, wherein a portion between the outermost elastic member and the side edge of the absorbent body has air permeability.   A waist flap extending in the width direction is formed at a position outward in the longitudinal direction from the front end edge or the rear end edge of the absorber, and one or a plurality of elastic members extending in the width direction are arranged on the waist flap. The absorbent article according to claim 1, wherein a portion between the elastic member located on the outermost side and the edge of the absorbent body has air permeability.   The absorber is arranged between the liquid-permeable top sheet and the liquid-impermeable or water-repellent and moisture-permeable back sheet, and the left and right side edges of the top sheet are more than the left and right side edges of the back sheet. The absorbent article according to claim 1, which also terminates inward in the width direction. The absorbent article according to any one of claims 1 to 4 , wherein the crimp rate of the long fibers is 10 to 60 %. The absorbent article according to any one of claims 1 to 5 , wherein a pair of three-dimensional gathers are formed on both sides in the longitudinal direction of the absorbent article. The absorbent article according to claim 6 , wherein two pairs of the three-dimensional gathers are formed.

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