JP2017108884A - Absorbent article - Google Patents

Abstract

The present invention provides an absorbent article in which the shape of the absorbent core does not easily collapse during wearing, the liquid absorbability of the absorbent core is excellent, and liquid leakage hardly occurs. An absorbent core has a honeycomb structure in a crotch portion. The honeycomb structure 41 includes a plurality of protrusions 411 integrally formed on one surface of the base 410 in a scattered pattern in a regular pattern, and a recess 412 which is a part of the base 410 where the protrusions 411 are not formed. It is composed of The convex portion 411 and the concave portion 412 have the same density, or the concave portion 412 has a lower density than the convex portion 411. [Selection] Figure 3

Description

  The present invention relates to an absorbent article such as a disposable diaper.

  A typical form of the absorbent article includes a liquid-permeable top sheet, a liquid-impermeable back sheet, and a vertically long absorbent body disposed between both sheets. As the absorbent body, those mainly composed of a liquid-retaining absorbent core containing an absorbent material such as wood pulp or a water-absorbing polymer are generally used. Regarding this absorbent core, a block-shaped absorbent core provided with a groove-like space extending in the planar direction is known. Due to its structure, the block-shaped absorbent core is easily deformed flexibly with external forces, so it conforms to the complex undulating skin surface and conforms to the human body that touches the surface without gaps, and the wearer's body It has the feature that it is excellent in the operation followability that is deformed in accordance with the movement of the skin and maintains the state of contact with the skin surface.

With respect to the block-shaped absorbent core, for example, Patent Document 1 is composed of a collection of hexagonal small absorbent portions extending in the longitudinal direction in plan view, and the small absorbent portions are arranged in a honeycomb shape at predetermined intervals. A block-shaped absorbent core is described.
In Patent Document 2, for the purpose of improving spot absorbability and body fluid diffusibility, the absorbent core has a two-layer structure of an upper layer and a lower layer, and the density of the lower layer relatively far from the skin of the wearer is It is described that the density is higher than the density of the upper layer, and as one of the densification means for such a lower layer, it is described that a depressed portion of an embossed pattern provided by pressing or embossing is provided in the lower layer. As an example of the recess, a groove-like recess that is continuous in a honeycomb shape is cited. The non-formed portion of the groove-like concave portion in the lower layer is a hexagonal embossed convex portion in plan view, and on the skin facing surface of the lower layer, a large number of the embossed convex portions are regularly arranged in the form of dots. Has been.

Further, in Patent Document 3, for the purpose of improving the absorbability of body fluid in the absorbent core, on the non-skin facing surface of the absorbent core, the abdominal side and the back side on both sides from the longitudinal center of the absorbent core. A plurality of vertical embossed recesses extending toward the portion are formed, and a plurality of hexagonal embossed protrusions and a honeycomb-shaped embossed recess located in the periphery thereof are formed on the ventral side portion and the back side portion. The formation of a diffusion embossed recess having an embossed pattern is described.
Further, Patent Document 4 describes an absorbent body in which a structure in which a low basis weight portion is arranged between hexagonal high basis weight portions adjacent to each other in plan view is repeated in the plane direction. According to Patent Document 4, such an absorbent body has high flexibility and improved fit to the skin, and the liquid diffusibility of the liquid in the low basis weight part is high, so that the liquid moves to the high basis weight part. It is said that the liquid absorption performance is excellent.

JP 2011-139897 A JP 2004-121382 A JP-A-2005-73921 JP 2013-85561 A

  When a block-like absorbent core is used for an absorbent article, the improvement of flexibility and liquid diffusibility can be expected by taking advantage of the features of the absorbent core, but the absorbency depends on the movement of the wearer during wearing. There is a concern that the shape of the absorbent core may collapse due to, for example, the core twisting or breaking. In particular, the crotch part arranged in the crotch part of the wearer in the absorbent article is sandwiched between the two thighs of the wearer and is subjected to excessive stress during wearing. The part located in the crotch portion of the absorbent core is undesirably unexpectedly deformed, such as broken or broken, and the shape tends to collapse at present.

  Therefore, the present invention relates to providing an absorbent article that is less likely to collapse the shape of the absorbent core during wearing, has excellent liquid diffusibility due to the absorbent core, and does not easily leak.

  The present invention comprises an absorbent core containing an absorbent material, and a surface material disposed on the skin-facing surface side of the absorbent core, and a crotch portion disposed in a crotch portion of a wearer when worn, An absorptive article having an abdominal side portion disposed on the abdomen side of the wearer from the crotch portion and a back side portion disposed on the back side of the wearer from the crotch portion, wherein the absorbent core is The crotch has a honeycomb structure, and the honeycomb structure has a plurality of protrusions integrally formed in a regular pattern in a dotted pattern on one side of the substrate, and non-projections of the protrusions on the substrate. It is configured to include a concave portion that is a forming portion, and the convex portion and the concave portion have the same density, or the concave portion provides an absorbent article having a lower density than the convex portion. is there.

  ADVANTAGE OF THE INVENTION According to this invention, the shape of an absorptive core is hard to collapse during wear, it is excellent in the diffusibility of the liquid by an absorptive core, and the absorbent article which does not raise | generate a liquid leak easily is provided.

FIG. 1 is a plan view schematically showing a skin facing surface, that is, a surface sheet side of a disposable diaper that is an embodiment of the absorbent article of the present invention, in which an elastic member of each part is expanded and expanded in a planar shape. It is a top view in a state. FIG. 2 is a cross-sectional view schematically showing a cross section taken along line II of FIG. FIG. 3 is an enlarged cross-sectional view showing a part of FIG. 2 in an enlarged manner. Fig. 4 is a perspective view schematically showing an enlarged part of the honeycomb structure in the absorbent core arranged in the diaper shown in Fig. 1. FIG. 5 is a plan view schematically showing a skin facing surface of the absorbent core arranged in the diaper shown in FIG. 1. FIG. 6 is a perspective view schematically showing an enlarged part of the surface sheet arranged in the diaper shown in FIG. 1. FIG. 7 is an enlarged perspective view schematically showing a part of another embodiment of the top sheet according to the present invention.

  Hereinafter, the absorbent article of this invention is demonstrated with reference to drawings based on the preferable embodiment. The disposable diaper 1 which is one Embodiment of the absorbent article of this invention, or its principal part is shown by FIGS. As shown in FIG. 1, the diaper 1 includes a crotch portion 1M disposed in the crotch portion of the wearer when worn, an abdominal side portion 1F disposed on the abdomen side of the wearer than the crotch portion 1M, and a crotch portion 1M. And a longitudinal direction X corresponding to the wearer's front-rear direction, extending from the abdominal side 1F to the back side 1R via the crotch 1M. , And a transverse direction Y orthogonal thereto. The abdominal side portion 1F, the crotch portion 1M, and the back side portion 1R correspond to respective regions when the diaper 1 is divided into three equal parts in the vertical direction X. The crotch part 1M has an excretion part facing part that is disposed to face an excretion part such as a wearer's penis when the diaper 1 is worn, and the excretion part facing part is usually a central part in the longitudinal direction X of the diaper 1 Or it is located in the vicinity.

  As shown in FIGS. 1 and 2, the diaper 1 is an absorbent body 4 having an absorbent core 40 and a surface material that is disposed on the skin-facing surface side of the absorbent body 4 and can come into contact with the wearer's skin when worn. A liquid-permeable top sheet 2 and a liquid-impermeable or water-repellent back sheet 3 disposed on the non-skin-facing surface side of the absorber 4, and in plan view as shown in FIG. The central part of the vertical direction X located in the crotch part 1M is formed in a vertically long hourglass shape that is bound inward and is long in one direction, that is, the vertical direction X. Each of the top sheet 2 and the back sheet 3 has a size larger than that of the absorber 4 interposed between the sheets 2 and 3. The back sheet 3 has a size larger than that of the top sheet 2 and extends outward from the peripheral edge of the absorbent body 4 to form the outer shape of the diaper 1 in a developed and extended state as shown in FIG. As the back sheet 3, various materials conventionally used for this type of absorbent article can be used without particular limitation, and a resin film, a laminate of a resin film and a nonwoven fabric, or the like can be used.

  In the present specification, the “skin facing surface” is a surface of the absorbent article or its constituent member (for example, the absorbent body 4) that is directed toward the wearer's skin when the absorbent article is worn, that is, relative to the wearer's skin. The side close to the skin, and the “non-skin facing surface” is directed toward the side opposite to the skin side when the absorbent article is worn, that is, the side relatively distant from the wearer's skin. It is the surface to be. In addition, "at the time of wearing" here means a state where a normal proper wearing position, that is, a correct wearing position of the absorbent article is maintained, and the absorbent article is in a state of being deviated from the wearing position. Is not included.

  Moreover, the side sheet | seat 5 is distribute | arranged to the right-and-left both sides along the vertical direction X in the surface sheet 2 side of the diaper 1, respectively. The side seat 5 has an inner edge along the vertical direction X, and an outer edge along the vertical direction X that is located outside the inner edge in the lateral direction Y, and has a flat surface as shown in FIG. In view, the inner edge overlaps with the absorber 4, and the outer edge extends outward in the lateral direction Y from the side edge along the longitudinal direction X of the absorber 4, as shown in FIG. 3 is joined. Between the side sheet 5 and the back sheet 3 in the left and right leg portions arranged around the legs of the wearer, a thread-like elastic member 50 is fixed in an elongated state along the vertical direction X. A pair of leg gathers is formed in the leg portion when the diaper 1 is worn by contraction of the elastic member 50. Further, a thread-like elastic member 51 is fixed to the inner edge portion of the side seat 5 in an elongated state along the longitudinal direction X. Accordingly, when the diaper 1 is worn, at least the crotch 1M due to the contraction of the elastic member 51. In the side sheet 5, the inner edge side stands up toward the wearer's skin side starting from the joint with the back sheet 3 to form a leak-proof cuff. This leak-proof cuff can prevent outflow of excretion fluid such as urine outward in the lateral direction Y, so-called lateral leakage. The top sheet 2, the back sheet 3, the absorbent body 4, the side sheet 5, and the elastic members 50 and 51 are joined to each other by a known joining means such as a hot-melt adhesive.

  The diaper 1 is a so-called unfolded disposable diaper. As shown in FIG. 1, a pair of fastening tapes 6 and 6 are provided on both side edges along the longitudinal direction X of the back side 1R of the diaper 1. . A fastening portion (not shown) made of a male member of a mechanical surface fastener is attached to the fastening tape 6. Moreover, the to-be-attached area | region 7 which consists of a female member of a mechanical hook-and-loop fastener is formed in the non-skin opposing surface of the belly side part 1F of the diaper 1. FIG. The to-be-attached region 7 is formed by attaching a female member of a mechanical hook-and-loop fastener to the non-skin facing surface of the back sheet 3 that forms the non-skin facing surface of the abdominal side portion 1F by a known joining means such as adhesive or heat seal. It is formed by joining and fixing, and the fastening portion of the fastening tape 6 can be detachably fastened.

Hereinafter, the absorber 4 will be described.
The absorber 4 has a shape that is long in the longitudinal direction X in a plan view as shown in FIG. 1, and extends from the ventral side 1F to the dorsal side 1R. The absorbent body 4 includes a liquid-retaining absorbent core 40 containing an absorbent material, and a core wrap sheet 45 that covers the skin facing surface and the non-skin facing surface of the absorbent core 40. The absorptive core 40 has an hourglass shape in which a central portion in the longitudinal direction, that is, the longitudinal direction X is bound inward in a plan view as shown in FIG. The absorbent core 40 and the core wrap sheet 45 are joined by a known joining means such as a hot melt adhesive. The absorber 4 (absorbent core 40) is formed symmetrically with respect to a virtual straight line (not shown) extending in the longitudinal direction X by dividing the diaper 1 into the transverse direction Y.

  The absorbent core 40 is formed by stacking a core forming material including an absorbent material. As the absorbent material, those normally used as a material for forming this type of absorbent core can be used without any particular limitation. For example, hydrophilic fibers such as wood pulp, synthetic fibers treated with a hydrophilizing agent, and water absorption Include polymer particles. That is, the absorbent core 40 may be a hydrophilic fiber stack or a structure in which water-absorbing polymer particles are supported on the stack.

  The absorbent core 40 has a honeycomb structure 41 at least in the crotch part 1M. FIG. 4 shows the skin-facing surface side of the honeycomb structure 41 shown in FIG. 2 and FIG. 3 which is a partially enlarged view thereof, that is, the honeycomb structure 41 in the crotch 1M. The honeycomb structure 41 is mainly composed of a base 410 having a concavo-convex structure on one side, specifically the skin-facing surface, and is integrally formed in a regular pattern in a dotted pattern on the skin-facing surface of the base 410. A plurality of convex portions 411 and a concave portion 412 that is a non-forming portion of the convex portion 411 in the base 410 are configured. That is, in the honeycomb structure 41, a plurality of hexagonal convex portions 411 in plan view are integrally formed on the skin-facing surface of the base 410, and the plurality of convex portions 411 are separated from each other and are individually honeycomb-shaped. Is arranged. The convex portion 411 has a solid structure and is filled with a core forming material. The plurality of convex portions 411 have the same height from the skin facing surface of the base 410.

  As shown in FIG. 4, the plurality of convex portions 411 are arranged in a regular pattern in a dotted pattern on one surface of the base 410, and more specifically, are arranged in a staggered manner. Here, the staggered arrangement refers to an arrangement in which the pitch of the convex portions 411 in adjacent rows is shifted when the rows of the plurality of convex portions 411 are arranged in parallel, in other words, the convex portions of a predetermined row. When 411 is projected in a direction orthogonal to the direction in which the row extends, the arrangement does not coincide with the projected image of the convex portion 411 adjacent to the row.

  Each of the plurality of convex portions 411 is surrounded by the concave portion 412. The concave portion 412 is a non-existing region of the convex portion 411 in the honeycomb structure 41 and is continuous over the entire area of the skin facing surface (convex portion forming surface) of the honeycomb structure 41. The skin facing surface of the honeycomb structure 41 has a concavo-convex structure composed of convex portions 411 and concave portions 412, whereas the non-skin facing surface is a flat surface having substantially no concavo-convex portions.

  In the base 410, the density of the convex portion 411 and the concave portion 412 (the bottom portion of the concave portion 412 and the non-formed portion of the convex portion 411) is the same, or the density of the concave portion 412 is lower than that of the convex portion 411 (that is, The convex portion 411 has a higher density than the concave portion 412). This means that the concavo-convex structure composed of the convex portions 411 and the concave portions 412 in the honeycomb structure 41 is not formed by embossing. That is, if the concavo-convex structure of the honeycomb structure 41 is formed by embossing, the concave portion 412 is a portion formed by compressing the raw sheet of the substrate 410 in the thickness direction in embossing. It is an embossed part, and the convex part 411 is a non-embossed part that is not embossed. The concave part 412 is a convex part 411 that is not consolidated because the core forming material is consolidated by embossing. Higher density than However, in the absorbent core 40 according to the present invention, since the concave portion 412 is not consolidated in the formation process like the convex portion 411, there is no substantial difference in density in comparison with the convex portion 411, and at least the honeycomb structure Immediately after manufacturing the body 41 (immediately after embossing), the convex portions 411 and the concave portions 412 have the same density. However, in a normal handling operation such as transportation of the honeycomb structure 41 having a uniform density, when pressure is applied to the honeycomb structure 41 in the thickness direction, for example, the various rolls such as a transport roll When pressure is applied to the entire honeycomb structure 41 in the thickness direction, the concave portion 412 having a relatively small thickness is not substantially pressurized and the convex portion 411 having a relatively large thickness. As a result, a state in which the concave portion 412 is lower in density than the convex portion 411 is formed. In other words, even if the purpose is to manufacture the honeycomb structure 41 having a uniform density, there may be a difference in density between the convex portion 411 and the concave portion 412 due to inevitable pressurization of the honeycomb structure 41 in the subsequent handling. Therefore, in the absorbent core according to the present invention, the density is uniform and the density is the same in the convex portion 411 and the concave portion 412, and the density of the concave portion 412 is lower than that of the convex portion 411. Types of forms are included.

  Such a honeycomb structure 41 with a uniform density can be manufactured by partially varying the amount of core forming material in a conventionally known method for manufacturing an absorbent core. Specifically, for example, in the method of obtaining the honeycomb structure 41 by sucking and depositing the core forming material supplied on the air flow onto the air-permeable mold formed on the outer peripheral surface of the rotary drum, The method of partially changing the air permeability of the molding die, the method of imparting irregularities corresponding to the irregular structure of the honeycomb structure 41 to the outer surface of the molding die on which the core forming material is piled, etc. Deliberately control the amount of pile. In the honeycomb structure 41 obtained by such a method, the portion having a relatively large amount of core forming material (high basis weight portion) corresponds to the convex portion 411, and the portion having a relatively small amount (low basis weight portion). It is the recess 412 that does.

  The absorbent core 40 having the honeycomb structure 41 has a so-called block shape in which a plurality of groove-shaped spaces extending in the plane direction and intersecting each other are provided, so that the absorbent core 40 is flexible with respect to external force. It is easy to deform, has excellent followability to the wearer's body, and can exhibit good fit. Moreover, since the recessed part 412 functions as a flow path for excrement liquid such as urine, the excretion liquid has excellent diffusibility in the surface direction. However, the expression of the function and effect by the absorbent core 40 is based on the premise that the unique block shape is maintained while the diaper 1 is worn, and the absorbent core 40 is broken or broken by the movement of the wearer. If the block shape of the absorbent core 40 collapses due to the occurrence of such as, there is a concern that the expected effects can not be fully expressed. In particular, since the crotch part 1M is likely to be excessively stressed during wearing, the block shape tends to collapse, and there is a concern that the action and effect inherent in the absorbent core 40 may not be sufficiently exhibited.

  However, the absorbent core 40 in the crotch part 1M is an ordinary block-like structure in which the absorbent core is partitioned into a plurality of rectangular regions in plan view by groove-like spaces extending in the vertical and horizontal directions. In addition, since the portion corresponding to the partition region is a convex portion 411 having a hexagonal shape in plan view, and the convex portion 411 is the honeycomb structure 41 arranged in a honeycomb shape, various portions caused by the movement of the wearer and the like It is difficult to deform due to stress from the direction, and the shape is difficult to collapse. Therefore, the diaper 1 including the absorbent core 40 is less likely to cause undesirable deformation or breakage of the absorbent core 40 during wearing, and the function and effect expected of the absorbent core 40 are sufficiently expressed. Excellent liquid leakage prevention property.

  In addition, as described above, the honeycomb structure 41 has the same density in the convex portion 411 and the concave portion 412 (the bottom portion of the concave portion 412 and the non-formed portion of the convex portion 411), or the concave portion 412 is in comparison with the convex portion 411. Because of the relatively low density, the concavo-convex structure is formed by embossing, and the recesses are more flexible and fit than the block-like structure with a relatively high density compared to the convex parts. As a result, it is excellent in terms of prevention of liquid leakage.

  As shown in FIGS. 2 and 3, the absorbent core 40 in the present embodiment includes a laminate 43 of a honeycomb structure 41 and a core element 42 that does not have a honeycomb structure in the crotch 1M. More specifically, the absorbent core 40 in the crotch part 1M includes a laminated body 43. The laminated body 43 includes a core element 42 that is relatively close to the skin of the wearer and a honeycomb that is relatively far from the skin of the wearer. It consists of a structure 41. In the laminate 43, a plurality of convex portions 411 are interposed between the core element 42 and the base body 410 (that is, the formation surface of the convex portions 411 in the honeycomb structure 41 and the core element 42 face each other), and the convex portions. A space 44 where no core forming material is present is formed in a region corresponding to the non-existing region 411, that is, the recess 412.

  Similarly to the honeycomb structure 41, the core element 42 is composed of a fiber stack of core forming materials. In this embodiment, the core element 42 has the same shape and dimensions as the honeycomb structure 41 in the crotch 1M in plan view. The core element 42 is essentially a base material that is substantially free of unevenness at the time before it is laminated with the honeycomb structure 41 and becomes a part of the laminate 43, but the laminate 43 of the present embodiment. In FIG. 5, the contact portion with the honeycomb structure 41 and the peripheral portion thereof are deformed, so that a concavo-convex structure is formed on the surface facing the substrate 410. More specifically, in the laminated body 43, as shown in FIG. 3, the tips of the plurality of convex portions 411 bite into the core element 42 on the side facing the substrate 410 (honeycomb structure 41), and the core The peripheral portion of the biting portion (contact portion with the tip of the convex portion 411) of the convex portion 411 in the element 42 is raised toward the concave portion 412 of the base body 410 to form a raised portion 420. That is, the protruding portion 420 of the core element 42 enters the non-existing region of the convex portion 411 in the honeycomb structure 41, that is, the concave portion 412, and the tip of each of the plurality of convex portions 411 that are in contact with the core element 42. Besieged.

  As shown in FIG. 3, the raised portion 420 of the core element 42 does not reach the base 410 of the honeycomb structure 41, and the space 44 is provided between the raised portion 420 and the base 410 (the bottom of the recess 412). Is formed. The space portion 44 is formed so as to surround each of the plurality of convex portions 44 of the honeycomb structure 41, and is continuous in the laminated body 43 corresponding to the concave portion 412. However, when some of the raised portions 420 reach the base body 410 unintentionally, the space portion 44 is not formed in that portion, and as a result, the continuity of the space portion 44 in the laminate 43 is lost. possible.

  Thus, in the crotch part 1M, which is a portion where excessive stress is easily applied during wearing, the absorbent core 40 includes the laminated body 43 of the honeycomb structure 41 and the core element 42, thereby having the core element 42. Therefore, as compared with the case where only the honeycomb structure 41 is used, the resistance to stress applied during wearing is further improved, so that the shape retention of the absorbent core 40 is improved, and thereby liquid diffusibility, fit, etc. Improvement of various characteristics can be expected. In particular, when a part of the core element 42 enters the recessed portion 412 of the honeycomb structure 41 as the raised portion 420, the resistance to the stress of the absorbent core 40 (laminated body 43) can be further improved. In addition, since the protruding portion 420 does not completely enter the concave portion 412, and the space portion 44 is formed inside the absorbent core 40 (laminated body 43), the good liquid diffusibility inherent in the honeycomb structure 41 is achieved. Is maintained.

  In addition, when the raised portion 420 of the core element 42 contains a water-absorbing polymer, for example, water-absorbing polymer particles, the shape retention of the raised portion 420 in a wet state is further improved, and the shape retention of the entire absorbent core 40 is improved. It leads to improvement. That is, when the raised portion 420 containing the water-absorbing polymer comes into contact with excretory fluid such as urine, the raised portion 420 expands with swelling due to absorption of the excreted fluid of the water-absorbing polymer. Therefore, the degree of adhesion with the convex portion 411 can be increased, and the shape retention of the raised portion 420 can be improved. In the core element 42, the water-absorbing polymer may be unevenly distributed in the raised portion 420, but normally, the water-absorbing polymer is uniformly distributed throughout the core element 42.

  The laminated body 43 is obtained by stacking the honeycomb structure 41 and the core element 42 and pressing in the thickness direction. In the laminated body 43, the tip of the convex portion 411 of the honeycomb structure 41 bites into the core element 42, and the peripheral portion of the biting portion of the convex portion 411 in the core element 42 forms a raised portion 420 into the concave portion 412 of the honeycomb structure 41. The entry is due to the pressure treatment after the honeycomb structure 41 and the core element 42 are overlapped. When the water-absorbing polymer is uniformly distributed throughout the core element 42 before the pressure treatment, the raised portion 420 formed by such pressure treatment contains the water-absorbent polymer. The honeycomb structure 41 and the core element 42 are joined and integrated with each other by entanglement of constituent fibers at the tip of the convex portion 41 without using a joining means such as an adhesive or heat seal. The degree of pressurization is preferably such that the raised portions 420 of the core element 42 do not reach the substrate 410 of the honeycomb structure 41 and the formation of the space 44 can be ensured.

From the viewpoint of more surely exhibiting the effects of the absorbent core 40 having the honeycomb structure 41 described above, it is preferable to set the dimensions and the like of the respective parts as follows.
The maximum length L (see FIGS. 3 and 4) of the convex portion 411 in the honeycomb structure 41 is preferably 10 mm or more, more preferably 5 mm or more, and preferably 30 mm or less, more preferably 20 mm or less. is there.
The height H (see FIGS. 3 and 4) of the convex portion 411 in the honeycomb structure 41 is preferably 1 mm or more, more preferably 2 mm or more, and preferably 5 mm or less, more preferably 3 mm or less.
In the honeycomb structure 41, the number of the convex portions 411 existing in an arbitrary region of 150 mm square is preferably 10 or more, more preferably 40 or more, and preferably 400 or less, more preferably 150 or less. .
The width W (see FIG. 3) of the recess 412 in the honeycomb structure 41 is preferably 1 mm or more, more preferably 2 mm or more, and preferably 5 mm or less, more preferably 4 mm or less.
The basis weight of the honeycomb structure 41 is preferably 350 g / m ² or more, more preferably 400 g / m ² or more, and preferably 550 g / m ² or less, more preferably 500 g / m ² or less.
The basis weight of the core element 42 is preferably 350 g / m ² or more, more preferably 400 g / m ² or more, and preferably 550 g / m ² or less, more preferably 500 g / m ² or less.

  FIG. 5 shows the entire skin facing surface of the absorbent core 40. As shown in FIG. 5, the absorbent core 40 has only the honeycomb structure 41 on the ventral side portion 1F and the back side portion 1R. That is, in the absorbent core 40, the laminated body 43 of the honeycomb structure 41 and the core element 42 exists only in the crotch part 1M, and the core element 42 exists in the stomach side part 1F and the back side part 1R. Only the honeycomb structure 41 exists. The absorptive core 40 in each of the ventral part 1F and the dorsal part 1R may also have a laminated body 43 like the crotch part 1M, but the ventral part 1F and the dorsal part 1R are connected to the crotch part 1M. In comparison, since the stress applied during wear is low due to the influence of the wearer's movement, the core element 42 may be omitted as shown in FIG.

  Further, in the absorbent core 40, as shown in FIG. 5, the entire area of the skin facing surface has a honeycomb structure, that is, the convex portions 411 are arranged in a honeycomb shape on the entire area of the skin facing surface. The honeycomb structure (convex portion 411) is formed only in the central portion in the lateral direction Y, and is not formed on both side portions thereof. The formation region of the convex portion 411, that is, the honeycomb structure region 411R extends over the entire length in the longitudinal direction X of the absorbent core 40. The honeycomb structure region 411R may be arranged in the entire transverse direction Y of the absorbent core 40. For example, the entire area of the skin facing surface of the absorbent core 40 may be the honeycomb structure region 411R. However, at least in the lateral direction Y of the absorbent core 40, if the honeycomb structure region 411R is arranged at the center, a predetermined purpose can be achieved. The ratio of the length in the lateral direction Y of the honeycomb structure region 411R to the length in the lateral direction Y of the absorbent core 40 is preferably 0.5 or more, more preferably 0.6 or more, as the latter / the former. Preferably it is 1 or less, More preferably, it is 0.8 or less. Here, the “lateral length of the honeycomb structure region” means the lateral direction Y having the smallest area among the virtual regions having a rectangular shape in plan view including all the convex portions 411 on the skin facing surface of the absorbent core 40. In the form of FIG. 5, it corresponds to the length of the distance between two dotted lines.

  Further, in the absorbent core 40, as shown in FIG. 5, the honeycomb structures 41 of the belly side portion 1F and the back side portion 1R are more flat than the honeycomb structure 41 of the crotch 1M. The size (area) in view is large, more specifically, the length of the diagonal line in plan view of the convex portion 411 is long. In general, when only the area of the convex portion 411 (the length of the diagonal line) is changed while the width of the concave portion 412, that is, the separation distance between the adjacent convex portions 411 and 411 is constant, the smaller the area of the convex portion 411 (the diagonal line) When the length is shorter, the resistance to stress is improved and the shape retention of the honeycomb structure 41 is improved, but on the other hand, the workability is lowered and the manufacturing efficiency of the honeycomb structure 41 may be reduced. Therefore, the “small convex portion 411” having low workability is not applied to the entire honeycomb structure 41, but is applied only to the crotch portion 1M in which high shape retention is required, as shown in FIG. It is. In the absorptive core 40 shown in FIG. 5, the abdominal side portion 1F and the back side portion 1R are given priority over a certain degree of workability while taking into account the shape retention, and are higher than those in the crotch 1M. Large convex portions 411 are arranged. According to such an absorbent core 40 in which the size (area) of the convex portion 411 in plan view is partially different, the balance between various properties such as shape retention, manufacturing efficiency, and manufacturing cost is good.

  The ratio of the length of the diagonal line of the convex part 411 in the ventral part 1F or the back part 1R to the diagonal length of the convex part 411 in the crotch part 1M is preferably 1 or more, more preferably 1 as the latter / the former. .5 or more, and preferably 5 or less, more preferably 3 or less. The length of the diagonal line of the convex part 411 is the length of the diagonal line in the plan view of the convex part 411 in an unloaded state, and is measured according to an ordinary method using a ruler.

  As the surface sheet 2, those conventionally used as the surface material in this type of absorbent article can be used without particular limitation, but the structure of the characteristic absorbent core 40 (honeycomb structure 41) described above is used. It is more effective to use one having a specific concavo-convex structure in accordance with the adoption. In this regard, in the present embodiment, as shown in FIGS. 2 and 3, a plurality of surface material convex portions 211 protruding toward the wearer's skin side are provided on the skin facing surface of the topsheet 2. 41 is formed integrally with a pattern corresponding to the formation pattern of the convex portions 411, and the surface material concave portions 212 having a higher density than the surface material convex portions 211 are present in the periphery of each surface material convex portion 211. ing.

  FIG. 6 shows the skin facing surface side of the topsheet 2. The surface sheet 2 is formed by partially performing known embossing on the raw sheet that is the raw material, and the embossed portion is formed by the material of the raw sheet being consolidated. The surface material concave portion 212 of the high-density portion formed as a result, and the portion not embossed, protrudes to one side in the thickness direction, specifically the skin facing surface side, to become the surface material convex portion 211. Since the surface material convex portion 211 is not consolidated by embossing, it is a low density portion having a lower density than the surface material concave portion 212. The surface sheet 2 in the present embodiment has a single layer structure, the surface material convex portion 211 has a hollow structure, and the inside thereof is not filled with a material for forming an original sheet. Moreover, in this embodiment, the whole area | region of the skin opposing surface of the surface sheet 2 is a formation area of the surface material convex part 211. FIG.

  In the surface sheet 2, as described above, the surface material convex portions 211 are integrally formed in a pattern corresponding to the formation pattern of the convex portions 411 in the honeycomb structure 41. Therefore, in the predetermined region of the surface sheet 2, The shape and size of the surface material convex portion 211 in plan view and the separation distance between adjacent surface material convex portions 211 and 211, that is, the width of the surface material concave portion 212 overlap the predetermined region of the honeycomb structure 41 in plan view. In the region, the shape and size of the convex portion 411 in plan view and the separation distance between the adjacent convex portions 411 and 211, that is, the width of the concave portion 412 are the same. In the surface sheet 2, the plurality of surface material convex portions 211 are respectively surrounded by the concave portions 412, and are continuous over the entire skin facing surface (convex portion forming surface) of the surface sheet 2.

  Thus, when the skin facing surface of the topsheet 2 has a concavo-convex structure composed of the surface material convex portions 211 and the surface material concave portions 212, compared to the case where the skin facing surface is a flat surface without concavo-convexities. Since the contact area with the skin of the wearer is reduced, the sticky feeling is reduced, and the breathability and cushion feeling can be improved. Moreover, since the surface material recessed part 212 functions as a flow path for excrement liquids such as urine, the excretion liquid quickly diffuses in the surface direction in the surface sheet 2 and leads to an improvement in the liquid absorption rate. And since the uneven structure of the surface sheet 2 is formed in a pattern corresponding to the honeycomb structure of the honeycomb structure 41, similarly to the honeycomb structure 41, there are various causes caused by the movement of the wearer of the diaper 1. It is difficult to deform due to stress from various directions, and the shape is difficult to collapse. In the diaper 1 having such a configuration, excretion fluid such as urine excreted in the excretory part-facing portion of the top sheet 2 passes through the top sheet 2 in the thickness direction while quickly diffusing in the surface direction by the top sheet 2. The excreted liquid that reaches the absorber 4 and reaches the absorber 4 is further diffused and absorbed and retained in the plane direction by the honeycomb structure 41 having excellent liquid diffusibility. As described above, the diaper 1 has a high liquid absorption capability due to the combination of the topsheet 2 and the honeycomb structure 41, and is excellent in liquid leakage prevention and fitting properties.

  Note that the top sheet 2 and the honeycomb structure 41 have a one-to-one correspondence between the plurality of surface material protrusions 211 of the surface sheet 2 and the plurality of protrusions 411 of the honeycomb structure 41 in a plan view as shown in FIG. It is ideal that they overlap so that they completely coincide with each other. However, unless such an ideal form is used, the above-described operational effect is not exhibited, and even if both convex portions 211 and 411 are misaligned, they are substantially There is no problem. The point is that the formation region of the surface material convex portion 211 in the surface sheet 2 and the formation region of the convex portion 411 in the honeycomb structure 41, that is, the honeycomb structure region 411R (see FIG. 5) may overlap.

As the surface sheet 2, for example, a non-woven fabric such as an air-through nonwoven fabric or a spunbond nonwoven fabric, a fiber sheet such as a woven fabric or a knitted fabric, a film or the like can be used, and a fiber sheet is preferably used from the viewpoint of the touch and the like. In particular, it is preferable to use a nonwoven fabric. The basis weight of the topsheet 2 is preferably 15 g / m ² or more, more preferably 20 g / m ² or more, and preferably 50 g / m ² or less, more preferably 40 g / m ² or less. The maximum length, height and number of the surface material convex portions 211 in the planar direction and the width of the surface material concave portions 212 can be set in the same manner as the convex portions 411 and the concave portions 412 in the honeycomb structure 41.

  FIG. 7 shows another embodiment of the top sheet according to the present invention. About this other embodiment, a different component from the surface sheet 2 of FIG. 6 is mainly demonstrated, the same component is attached | subjected the same code | symbol and description is abbreviate | omitted. The explanation about the top sheet 2 is applied as appropriate to the components that are not particularly explained.

  The top sheet 2A in FIG. 7 is different from the top sheet 2 in FIG. 6 having a single layer structure in that it has a laminated two-layer structure in which two sheets 20 and 21 are laminated. In the topsheet 2A, the first sheet 20 that is relatively close to the skin of the wearer has a concavo-convex structure composed of the top surface convex portion 211 and the top surface concave portion 212, that is, a pattern corresponding to the honeycomb structure of the honeycomb structure 41. The 2nd sheet | seat 21 which has an uneven | corrugated structure and is relatively far from a wearer's skin is a flat flat sheet | seat substantially without an unevenness | corrugation. The surface sheet 2A is integrated in the thickness direction by embossing by superimposing the original sheet of the first sheet 20 and the original sheet of the second sheet 21 (both original sheets are flat flat sheets without unevenness). The two sheets 20 and 21 are embossed parts and are joined to each other by heat fusion at a relatively high-density surface material concave part 212. Both sheets 20 and 21 may be of the same type or different from each other. Such a surface sheet having a multilayered multilayer structure can be produced according to the method for producing a composite sheet described in, for example, JP-A-2015-112343.

  Although the present invention has been described above, the present invention is not limited to the above-described embodiments, and can be appropriately changed without departing from the spirit of the present invention. For example, in the embodiment, in the laminated body 43, the core element 42 is relatively close to the wearer's skin, and the honeycomb structure 41 is relatively far from the wearer's skin. Conversely, the honeycomb structure 41 may be relatively close to the wearer's skin, and the core element 42 may be relatively far from the wearer's skin. Further, in the above-described embodiment, the core element 42 has the same shape and the same size as the honeycomb structure 41 in the crotch 1M in a plan view. What is necessary is just to have the planar view shape and dimension which can coat | cover the structure area | region 411R (refer FIG. 5). In addition, for the purpose of preventing the excretion fluid from transferring from the absorbent core 40 to the wearer's skin (so-called liquid return), a sublayer or the like is provided between the topsheet 2 and the absorbent body 4 (core wrap sheet 45). A fluid-permeable bodily fluid backflow prevention layer, also called a liquid-permeable body fluid, may be interposed.

  The absorbent article of the present invention is not limited to the deployable disposable diaper as in the above-described embodiment, and widely includes articles used for absorbing bodily fluids (urine, menstrual blood, loose stool, sweat, etc.) discharged from the human body. Also included are pants-type disposable diapers, sanitary napkins, sanitary shorts, and the like.

1 disposable diaper (absorbent article)
1F Abdominal side 1M Crotch 1R Back side 2,2A Surface sheet (surface material)
211 surface material convex part 212 surface material concave part 3 back sheet 4 absorber 40 absorbent core 41 honeycomb structure 410 base 411 convex part 411R honeycomb structure area (convex part formation area)
412 Concave part 42 Core element 43 Laminated body 44 Space part 45 Core wrap sheet 5 Side sheet 6 Fastening tape 7 Sticking area X Longitudinal direction Y Lateral direction

Claims (6)

An absorbent core including an absorbent material, and a surface material disposed on the skin-facing surface side of the absorbent core, and a crotch portion disposed in a crotch portion of the wearer when worn; An absorbent article having an abdominal side portion arranged on the abdomen side of the wearer and a back side portion arranged on the back side of the wearer from the crotch part,
The absorbent core has a honeycomb structure at the crotch portion, and the honeycomb structure includes a plurality of convex portions integrally formed in a regular pattern in a dotted pattern on one surface of the substrate, Including a concave portion that is a non-forming portion of the convex portion,
The absorbent article in which the density is the same in the convex part and the concave part, or the density of the concave part is lower than that of the convex part.   The absorbent core in the crotch includes a laminate of the honeycomb structure and a core element not having a honeycomb structure, and a plurality of the convex portions between the core element and the base in the laminate. The absorbent article according to claim 1, wherein a space is formed at a site corresponding to the recess.   In the laminated body, the ends of the plurality of convex portions bite into the core element facing surface side of the base, and the peripheral portions of the convex portions of the core element are in the concave portions of the base. The absorbent article according to claim 2, wherein the absorbent article protrudes upward, and the space is formed between the raised portion of the core element and the base body.   The absorbent article according to claim 3, wherein a water-absorbing polymer is contained in the raised portion of the core element.   The absorbent core has only the honeycomb structure on the belly side portion and the back side portion, and the honeycomb structures on the belly side portion and the dorsal side portion are different from the honeycomb structure body on the crotch portion. And the magnitude | size in planar view of the said convex part is large, The absorbent article as described in any one of Claims 1-4.   A plurality of surface material protrusions protruding toward the skin side of the wearer are integrally formed on the skin facing surface of the surface material in a pattern corresponding to the formation pattern of the protrusions in the honeycomb structure, and The absorbent article as described in any one of Claims 1-5 in which the high-density surface material recessed part exists in the peripheral part of each said surface material convex part compared with this surface material convex part.

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