JP2012157476A - Absorptive article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an absorptive article which is excellent in fitting property to the body of a wearer, and is hard to generate the leakage of excretion liquids.SOLUTION: The absorptive article 1 includes an absorptive core 40. On the absorptive core 40, a slit 5 which does not penetrate the absorptive core 40 in the thickness direction, and also, has an opening section 50 on the skin confronted surface 40a side or the skin non-confronted surface 40b side of the absorptive core 40 is formed by extending in the longitudinal direction of the absorptive article 1. The slit 5 includes a section where the width of the slit 5 gradually increases or decreases from the skin confronted surface 40a side to the skin non-confronted surface 40b side of the absorptive core 40. Then, the opening section 50 of the slit 5 is present on the side where the width of the slit 5 is relatively wider.

Description

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

  As an absorbent article such as a disposable diaper, a liquid-permeable surface sheet that forms a skin-facing surface, a liquid-impermeable back sheet that forms a non-skin-facing surface, and an absorbent body disposed between these sheets are provided. thing is known. Moreover, what is comprised as an absorber including the absorptive core containing hydrophilic fibers, such as wood pulp, and / or a water absorbing polymer, and the core wrap sheet which coat | covers this absorptive core is known. .

  In addition, for the purpose of improving the absorbability and fitability, there is a technique for forming a portion of the absorbent core where the material for forming the absorbent core does not exist or a relatively small portion (such as a groove or a through hole). Are known. For example, Patent Document 1 describes an absorbent structure in which an absorbent core made of cellulose fibers is partially compressed to form a reservoir and a channel, thereby absorbing and retaining the total urinary excretion of an adult. Has been.

  Moreover, in patent document 2, the cross-sectional view rectangular shape along the longitudinal direction of this absorptive core is provided in each skin opposing surface and non-skin opposing surface of an absorptive core for the purpose of the improvement of the fit property with respect to a wearer's body. The formation of grooves is described. According to Patent Document 2, the absorbent core in which such a groove is formed is said to be excellent in fit because it is bent along the groove when it is disposed in the crotch part of the wearer.

  Further, Patent Document 3 discloses that the absorbent core is formed on the absorbent core in order to prevent improper wrinkling such that the absorbent body (absorbent core) rises on the wearer side when the absorbent article is worn. Forming an opening extending in the direction and extending continuously or discontinuously in the longitudinal direction of the absorbent core.

JP 59-207150 A JP 2004-41311 A JP 2007-215688 A

  Since a disposable diaper having an absorbent core (absorber) has a predetermined thickness and a predetermined rigidity, it is not easy to attach it to each part of the body such as the crotch part with good fit. If the diaper is not worn on the body with good fit and a gap is formed between the body and the diaper, the excretion fluid may leak out depending on the degree of the gap. Conventional absorbent articles as described in Patent Documents 1 to 3 cannot be said to have sufficient fit with the wearer's body, and there is room for improvement.

  Therefore, the subject of this invention is providing the absorbent article which is excellent in the fit with respect to a wearer's body, and does not raise | generate the leakage of excretory fluid easily.

  The present invention is an absorbent article comprising an absorbent core, wherein the absorbent core does not penetrate the absorbent core in the thickness direction and the skin-facing surface side of the absorbent core or non-skin facing A slit having an opening on the surface side is formed extending in the longitudinal direction of the absorbent article, and the slit has a width from the skin facing surface side of the absorbent core toward the non-skin facing surface side. By providing an absorbent article having a portion that gradually increases or decreases, and the opening of the slit exists on the side where the width of the slit is relatively wide, It has been solved.

  ADVANTAGE OF THE INVENTION According to this invention, the absorbent article which is excellent in the fit with respect to a wearer's body, and hardly raise | generates the excretion fluid leak is provided.

FIG. 1 is a view showing an example of a disposable diaper as an embodiment of the absorbent article of the present invention, and is a skin-facing surface side (surface sheet side) showing a state in which the elastic member of each part is expanded and expanded in a flat shape ) is a schematic plan view of the. 2 is a schematic cross-sectional view showing a cross section taken along the line II (cross section in the width direction) of FIG. FIG. 3 is a schematic diagram of a wearing state of the disposable diaper shown in FIG. 1. 4A and 4B are schematic cross-sectional views in the width direction of other embodiments of the slit according to the present invention, respectively. FIG. 5 is a schematic cross-sectional view in the width direction of another embodiment of the absorbent body according to the present invention.

  Hereinafter, the absorbent article of the present invention will be described based on a disposable diaper which is a preferred embodiment thereof with reference to the drawings. The diaper 1 of this embodiment is equipped with the absorptive core 40 of a shape long in one direction X, as shown in FIG.1 and FIG.2. The absorbent core 40 is covered with a core wrap sheet 41 to constitute the absorbent body 4.

  More specifically, the diaper 1 of the present embodiment is a so-called unfolded disposable diaper. As shown in FIGS. 1 and 2, a liquid-permeable surface sheet 2 that forms a skin facing surface, a non-skin facing surface, A liquid-impermeable or water-repellent (hereinafter collectively referred to as “liquid-impermeable”) back sheet 3 to be formed, and a liquid-retaining absorbent 4 disposed between both sheets 2 and 3 are provided. Yes. Each of the top sheet 2, the back sheet 3, and the absorber 4 has a vertically long shape that is long in one direction (vertical direction) X. Each of the top sheet 2 and the back sheet 3 has a size larger than that of the absorber 4, and extends outward from the peripheral edge of the absorber 4. As shown in FIG. 2, the width of the top sheet 2 in the width direction (lateral direction) Y is smaller than the width of the back sheet 3 in the width direction (lateral direction) Y.

  As shown in FIG. 1, the diaper 1 has, in the longitudinal direction (longitudinal direction) X, a dorsal side portion A arranged on the back side of the wearer when worn and a ventral side arranged on the ventral side of the wearer when wearing. It has a part B and a crotch part C on which the wearer's crotch is arranged when worn. The crotch part C includes an excretion part facing part that is disposed so as to face the wearer's excretion part when worn, and is located at the central part in the longitudinal direction X of the diaper 1. The diaper 1 has an hourglass shape in which both side edges of the crotch part C are curved in an inward arc shape, and the center part in the longitudinal direction X is inwardly bounded in a plan view as shown in FIG. Yes.

  In the present specification, the skin facing surface is a surface of the absorbent article (disposable diaper) or a component thereof (for example, the absorbent core 40) that is directed toward the wearer's skin when the absorbent article is worn, The facing surface is a surface of the absorbent article or its constituent member that is directed to the side opposite to the skin side (clothing side) when the absorbent article is worn. The longitudinal direction (longitudinal direction) is a direction along the long side of the absorbent article or its constituent members, and the width direction (lateral direction) is a direction orthogonal to the longitudinal direction. In the figure, the direction indicated by the symbol X is the longitudinal direction (vertical direction) of the diaper 1 (absorbent core 40), and the direction indicated by the symbol Y is the width direction (lateral direction) of the diaper 1 (absorbent core 40). It is.

  The liquid-retaining absorbent core 40 constituting the absorbent body 4 has both side edges of the crotch portion C curved inwardly in an arcuate shape, and in the plan view as shown in FIG. It has an hourglass shape that is bound inward. Moreover, the core wrap sheet | seat 41 which comprises the absorber 4 is one continuous sheet | seat, and covers the whole skin opposing surface 40a of the absorptive core 40, as shown in FIG. Is extended outward from both side edges along the longitudinal direction X in the width direction Y, and the extended portion is wound down below the absorbent core 40 to cover the entire non-skin facing surface 40b of the absorbent core 40. Is covered. The absorbent core 40 and the core wrap sheet 41 may be joined by a known joining means such as a hot-melt adhesive.

  As shown in FIG. 1 and FIG. 2, side sheets 62 each having a thread-like elastic member 61 fixed in an extended state are arranged on one side edge of each side part along the longitudinal direction X of the diaper 1. A pair of three-dimensional gathers are formed in the crotch part C when worn. Further, between the top sheet 2 and the back sheet 3 in the left and right leg portions disposed around the wearer's legs, a thread-like elastic member 63 is disposed in a stretched state along the longitudinal direction X. A pair of leg gathers is formed in the leg portion at the time by the contraction of the elastic member 63. A belt-like elastic member 64 extends along the width direction Y between the top sheet 2 and the back sheet 3 at the waist portions (end portions in the longitudinal direction X) of the back side portion A and the ventral side portion B. It is arranged in a state and a waist gather is formed. The pair of side sheets 62 and 62, the top sheet 2, the absorber 4, the elastic members 63 and 64, and the back sheet 3 are joined to each other by a known joining means such as a hot-melt adhesive.

  As shown in FIG. 1, a pair of fastening tapes 8, 8 are provided on both side edges along the longitudinal direction X of the back side A of the diaper 1. More specifically, the both sides along the longitudinal direction X of each of the back side portion A and the ventral side portion B extend outward in the width direction Y from both side edge portions along the longitudinal direction X of the absorbent body 4. A pair of side flaps 7 and 7 is formed, and a fastening tape 8 is attached to each of the pair of side flaps 7 on the back side A so as to extend outward in the width direction Y. A fastening part 81 made of a male member of a mechanical surface fastener is attached to the fastening tape 8.

  In addition, a non-skin facing surface of the ventral side B of the diaper 1 is formed with an attachment region 9 made of a female member of a mechanical surface fastener. The to-be-attached region 9 is formed by bonding and fixing a female member of a mechanical surface fastener to the non-skin facing surface of the back sheet 3 by a known joining means (for example, an adhesive or heat seal). The fastening part 81 of the tape 8 can be detachably fastened.

  One of the main features of the diaper 1 of the present embodiment is that the slit 5 having a specific shape is formed in the absorbent core 40. That is, as shown in FIGS. 1 and 2, the absorbent core 40 does not penetrate the absorbent core 40 in the thickness direction and has an opening 50 on the non-skin facing surface 40 b side of the absorbent core 40. The slit 5 is formed extending in the longitudinal direction X of the absorbent core 40. In the absorbent core 40, a plurality of (two) continuous linear (rectangular) slits 5 extending in the longitudinal direction X are formed at predetermined intervals in the width direction Y of the absorbent core 40. These two slits 5 and 5 are parallel to each other and have the same length in the longitudinal direction X, and are formed symmetrically across an imaginary straight line (not shown) that bisects the absorbent core 40 in the width direction Y. . The interval between the two slits 5 and 5 is preferably 10 to 50 mm.

  As shown in FIG. 2, the slit 5 has a width W <b> 4 (see FIG. 1, a length in a direction Y orthogonal to the direction X in which the slit 5 extends) from the skin facing surface 40 a side of the absorbent core 40 to the non-skin facing surface. It has a portion that gradually increases toward the 40b side, and an opening 50 exists at the end in the thickness direction (depth direction of the slit 5) on the side where the width W4 is relatively wide. The slit 5 in the present embodiment has a trapezoidal shape (isometric leg) in a cross-sectional view in the width direction Y as shown in FIG. 2, and the width W4 of the entire slit 5 is non-skin from the skin facing surface 40a side. It gradually increases toward the facing surface 40b. When the width W4 of the slit 5 gradually increases from the skin facing surface 40a side to the non-skin facing surface 40b side in this way, for example, when the width W4 does not change in the thickness direction of the absorbent core 40 ( For example, as will be described later, the absorbent core 40 (diaper 1) has a slit 5 as a folding line and a width W4 that is relatively wide (as compared to a case where the sectional view of the slit 5 is rectangular). It becomes easy to bend by the skin facing surface 40b side (see FIG. 3).

  The slit 5 is formed at least in the crotch part C (the excretory part facing part). As shown in FIG. 1, the slit 5 in the present embodiment is formed on the dorsal side A through the crotch C (the excretory part-facing part) from the vicinity of the longitudinal end of the absorbent core 40 on the ventral part B side. It extends continuously and linearly over the part near the crotch C, and the length at the back side A is shorter than the abdomen B and the crotch C, and includes the crotch C. It is biased to the ventral part B side. Such a formation position of the slit 5 in the present embodiment corresponds to a region where urine is excreted and the vicinity thereof.

  The slit 5 deposits the forming material of the absorbent core 40 in the deposition process of the forming material of the absorbent core 40 (fiber material such as wood pulp, particles of water-absorbing polymer, etc.) at the time of manufacturing the absorbent core 40. This is a site formed by intentional inhibition, and the slit 5 has substantially no material for forming the absorbent core 40. “Substantially no material is formed in the slit” means that the material for forming the absorbent core 40 is unintentionally present in the slit 5 (based on the basis weight of the periphery of the slit 5 in the absorbent core 40). Also exists at low basis weights).

  The absorbent core 40 having the slits 5 can be manufactured in accordance with a conventionally known method for manufacturing an absorbent core. For example, the material for forming the absorbent core 40 supplied on an air flow is applied to the outer peripheral surface of the rotating drum. In the method of obtaining the absorbent core 40 by sucking and depositing on the formed mold, the mold has a predetermined pattern as the mold (for example, a portion corresponding to the slit 5 protrudes upward compared to the peripheral portion. In the absorbent core 40 thus obtained, the portion where the forming material is not deposited (the portion where the forming material is not substantially present) is the slit 5.

  As described above, the slit 5 is a non-penetrating slit that does not penetrate the absorbent core 40 in the thickness direction, and therefore, the skin facing surface 40a of the absorbent core 40 in the slit 5 and the core wrap sheet 41 is formed. The material for forming the absorbent core 40 is between the portions to be coated (that is, the portion of the absorbent core 40 adjacent to the slit 5 in the thickness direction of the absorbent core 40 (the side opposite to the opening 50)). It accumulates and forms the opening part 40c. The opening facing portion 40c is not compressed in the thickness direction at the time of manufacturing the absorbent core 40, and thus is not consolidated, like the portions other than the slit 5 in the absorbent core 40. In other words, the portion of the absorbent core 40 that is not consolidated is the slit 5 and the opening facing portion 40 c located on the opposite side of the opening 50 of the slit 5.

  The non-consolidated opening facing portion 40c is obtained by forming the slit 5 without intentionally depositing the forming material of the absorbent core 40 in the manufacturing method of the absorbent core 40 described above. A method other than the slit forming method, for example, manufacturing an absorbent core having no slit, and subjecting a predetermined portion of the absorbent core to post-processing such as embossing, die cutting, and cutting. not be obtained by a method of forming a. Since these post-processing compresses the absorbent core in the thickness direction, the opening facing portion adjacent to the slit obtained through the post-processing in the thickness direction is consolidated by the post-processing. Because.

  As one of the effects by the slit 5, the improvement of the fitting property with respect to the wearer's body of the diaper 1 is mentioned. That is, the diaper 1 (absorbent core 40), in particular, the region from the ventral side B to the crotch C (the front region of the diaper 1) where the slit 5 is biased exists, as shown in FIG. In the wearing state, when the wearer 10 is compressed in the width direction Y by the thigh of the wearer 10 or the like, a portion (outside in the width direction Y than the two slits 5, 5 extending in the longitudinal direction X) ( The outer portion is bent toward the non-skin facing surface side of the diaper 1 with the slit 5 as a fold line (so that the fold line overlaps with the slit 5), whereby the diaper 1 is in close contact with the skin 10a at the crotch part of the wearer 10 Since it deforms so as to follow with good performance, good fit is obtained. That is, the slit 5 functions as a flexible shaft of the diaper 1 (absorbent core 40).

  Even if the slit 5 is a through-type slit that penetrates the absorbent core 40 in the thickness direction, like the opening described in Patent Document 3, it can function as the flexible shaft described above. However, in that case, the continuity of the absorbent core is cut off in the through-type slit, so that the shape retention of the absorbent core is reduced, and the liquid diffusibility and rewetting performance are hindered. There is a risk of inconvenience such as On the other hand, the slit 5 according to the present embodiment is a non-penetrating slit as described above, and the absorbent core 40 has absorptivity at a portion adjacent to the slit 5 in the thickness direction of the absorbent core 40. Since the material for forming the core 40 is deposited to form the opening facing portion 40c, the continuity of the absorbent core 40 is maintained, and the above-described disadvantage does not occur.

  Further, when the opening facing portion 40c exists but is consolidated, [the opening facing portion 40c is a part other than the slit 5 in the absorbent core 40 (for example, an opening facing portion described later) In the case of a higher density than the peripheral portion of 40c), since the consolidated opening facing portion 40c is stiff and hard, in the hard opening facing portion 40C and the slit 5 adjacent thereto in the thickness direction, The diaper 1 (absorbent core 40) is difficult to bend, and as a result, a fold line is formed at a position off the slit 5, and the diaper 1 (absorbent core 40) may be bent as designed. In such a case, the effect of improving the fit may not be obtained as expected, but the opening facing portion 40c in the present embodiment is not consolidated as described above, and the opening facing portion 40c. The density D1 is equal to or more than the density D2 of the periphery of the opening facing portion 40c in the absorbent core 40 (a region within 5 mm from the opening facing portion 40c in the absorbent core 40 excluding the slit 5). Therefore, the bending at the opening facing portion 40c is not likely to be hindered.

  The reason why the opening facing portion 40c that is not consolidated is lower in density than the peripheral portion is as follows. That is, in the conveyance process after the formation of the slit 5 (opening facing portion 40c) at the time of manufacturing the absorbent core 40, pressure is applied to the entire absorbent core 40 by various rolls such as a conveyance roll in the thickness direction. In addition, the peripheral portion of the opening facing portion 40c may be compressed to some extent by the pressure to increase the density, whereas the opening facing portion 40c has a substantial thickness (absorbent core 40) compared to the peripheral portion. Therefore, it is hardly subjected to the pressure and is not substantially compressed. That is, at the time of manufacturing the absorbent core 40, the density of the opening facing portion 40c does not substantially change, whereas the density of the peripheral portion may increase due to compression or the like during transportation. The density of the opening facing portion 40c is relatively low.

  Moreover, the improvement of the absorbability of excretion liquid is mentioned as another one of the effect by the slit 5. FIG. That is, when the slit 5 in which the material for forming the absorbent core 40 does not substantially exist is formed in the absorbent core 40 so as to extend in the longitudinal direction X of the absorbent core 40, the excretion of the crotch part C is performed. Since the excretion fluid such as loose stool that has been excreted locally at the part facing portion rapidly diffuses in the longitudinal direction X of the absorbent core 40 using the slit 5 as a conduction path, the excretion fluid is substantially eliminated in the absorbent core 40. The portion to be absorbed increases, thereby reducing wet back such as urine and loose stool (a phenomenon in which excretory fluid that has permeated through the top sheet 2 is not retained by the absorber 4 and returns to the top sheet 2). In particular, in the initial excretion, the slit 5 functions as a storage unit for temporarily storing the initial excretory liquid, so that the absorbability of excreted liquid such as loose stool is improved.

  In the present embodiment, the non-consolidated opening facing portion formed by depositing the forming material of the absorbent core 40 on the skin facing surface 40a side of the portion of the absorbent core 40 where the slit 5 is formed. Since 40c exists, the excreted liquid that has sequentially passed through the top sheet 2 and the core wrap sheet 41 and reached the skin facing surface 40a of the absorbent core 40 diffuses in the width direction Y at the opening facing portion 40c. As a result, the entire absorbent core 40 can be used to absorb and retain excretory fluid, and the effect of reducing wetback such as urine and loose stool is further improved.

  If the opening facing portion 40c does not exist, that is, if the slit 5 penetrates the absorbent core 40 in the thickness direction, the through-type slit 5 moves in the width direction Y of excretory fluid. Since the diffusion is disrupted, the effect of improving the utilization efficiency of the absorbent core 40 cannot be expected so much. Further, when the opening facing portion 40c exists but is consolidated [the opening facing portion 40c is a part other than the slit 5 in the absorbent core 40 (for example, the periphery of the opening facing portion 40c). If the density is higher than that of the part), the diffusion of the liquid is not performed quickly, and the liquid diffusion of the consolidated part is delayed. Absent.

  From the viewpoint of ensuring the above-described effects by the slit 5 more reliably, the width W4 (see FIG. 1) of the slit 5 is preferably 1 to 20 mm, more preferably 1 to 10 mm. Further, the width W4s of the narrowest portion of the slit 5 is preferably 1 to 10 mm, and more preferably 1 to 5 mm. From the same point of view, the total W50 of the width W4s of the narrowest portion of all the slits 5 existing in the crotch C with respect to the full width W0 in the width direction Y of the absorbent core 40 in the crotch C (the excretory part facing portion). The ratio (W50 / W0) is preferably 0.02 to 0.3, more preferably 0.05 to 0.25.

  If the formation material of each part in the diaper 1 is demonstrated, as the surface sheet 2 and the back surface sheet 3, various things conventionally used in the said technical field can be used. As the surface sheet 2, various liquid-permeable sheet materials such as a nonwoven fabric and an apertured film can be used. As the back sheet 3, various liquid impervious materials such as a resin film having no moisture permeability, a resin film having fine pores and moisture permeability, a nonwoven fabric such as a water-repellent nonwoven fabric, and a laminate of these and other sheets. Or water repellent materials can be used. Moreover, as the side sheet | seat 62, the thing similar to the back surface sheet 3 can be used.

As the absorbent core 40, for example, a fiber assembly made of hydrophilic fibers such as wood pulp or synthetic fiber, or a fiber assembly in which a particulate water-absorbing polymer is held can be used. The density of the absorbent core 40 is preferably 0.03 to 0.2 g / cm ³ , more preferably 0.06 to 0.15 g / cm ³ . When the density of the absorbent core 40 is in the above range, the absorbent body 4 (absorbent core 40) that is soft and excellent in liquid absorbability can be obtained. As the core wrap sheet 41, for example, paper such as tissue paper, various nonwoven fabrics, and a liquid-permeable sheet material such as an apertured film can be used.

  The diaper 1 of the present embodiment is used in the same manner as a known unfolded disposable diaper. Since the diaper 1 of the present embodiment flexibly bends and deforms the slit 5 as a folding line as shown in FIG. 3 due to the function as the flexible shaft of the slit 5 described above, it fits the wearer's body. Excellent in properties. Moreover, the diaper 1 of this embodiment is also excellent in the absorbability of excretion liquid by the liquid permeability / diffusion function with respect to the excretion liquid of the slit 5 mentioned above, and is compatible with the improvement of the leak-proof property due to the improvement of the fit. As a result, a high leakage prevention property can be exhibited.

  The principal part of other embodiment of the absorbent article of this invention is shown by FIG.4 and FIG.5. In other embodiments to be described later, constituent parts different from the above-described embodiments will be mainly described, and the same constituent parts are denoted by the same reference numerals and description thereof will be omitted. The description of the above-described embodiment is applied as appropriate to components that are not particularly described.

  4 (a) and 4 (b) show another embodiment of a slit according to the present invention. In the slit 5A shown in FIG. 4A, the width of the slit 5A is from the skin facing surface 40a side of the absorbent core toward the non-skin facing surface 40b side, similarly to the slit 5 having a trapezoidal shape in cross section in the above embodiment. It has a gradually increasing portion, and the opening 50 of the slit 5A exists on the side where the width of the slit 5A is relatively wide. The slit 5 </ b> A has a shape in which a trapezoidal protrusion is connected to the top of a semicircle in a cross-sectional view in the width direction Y.

  On the other hand, the slit 5B shown in FIG. 4B has a trapezoidal shape in the width direction Y in the same manner as the slit 5 of the above embodiment (isosceles), but the width change is opposite to the slit 5. It has become. That is, the slit 5B has a portion whose width gradually decreases from the skin facing surface 40a side to the non-skin facing surface 40b side of the absorbent core 40, and the width of the slit 5B is relatively wide. On the side, there is an opening 50 of the slit 5B. The opening facing portion 40c shown in FIG. 4B exists on the non-skin facing surface 40b side of the absorbent core 40 and is closer to the back sheet 3 (not shown in FIG. 4) than the opening 50.

  FIG. 5 shows another embodiment of the absorbent body according to the present invention. The absorbent body 4 in the embodiment has a single layer structure including one absorbent core 40, but the absorbent body 4A illustrated in FIG. 5 has a multilayer structure including a plurality of absorbent cores 40 (two layers). is there. The effect similar to the said embodiment is show | played also by the absorbent article comprised including 4 A of absorbers.

  The present invention is not limited to the above-described embodiment, and can be appropriately changed without departing from the spirit of the present invention. For example, in the above-described embodiment, the slit 5 extending in the longitudinal direction X of the absorbent core 40 is biased toward the ventral side B including the crotch C, but may be formed only in the crotch C. Alternatively, it may be biased toward the back side A including the crotch portion C, or continuously over the entire length in the longitudinal direction X without being biased to a specific portion in the longitudinal direction X of the absorbent core 40. It may be formed. The number of slits 5 is not particularly limited, and for example, one slit may be formed at the center in the width direction Y of the absorbent core 40 (on an imaginary straight line that bisects the absorbent core 40 in the width direction Y). Moreover, the extending direction of the slit according to the present invention is not limited to the longitudinal direction of the absorbent core (absorbent article), and may be the width direction.

  Moreover, in the said embodiment, the core wrap sheet | seat 41 is one continuous sheet | seat, this sheet | seat is bend | folded along the absorptive core 40, and the both ends of the longitudinal direction X of the absorptive core 40 are remove | absorbed. The entire surface of the core 40 was covered, but instead of this, two core wrap sheets 41 were used, on the one hand covering the skin facing surface 40a of the absorbent core 40 and on the other hand non-skin facing surface 40b. May be coated.

  Further, a sublayer sheet may be interposed between the top sheet 2 and the absorber 4. The sublayer sheet has an effect of reinforcing the liquid absorbing ability of the diaper 1 and reducing a phenomenon (wet back) in which the liquid absorbed by the absorbent body 4 returns to the surface sheet 2 side. As the sublayer sheet, a sheet mainly composed of hydrophilic fibers such as wood pulp (a sheet having a hydrophilic fiber content of preferably 90% by mass or more) can be used. Examples of the sheet include paper, non-woven fabric, the web, and the like. The arrangement form of the sub-layer sheet is not particularly limited, and may be arranged from the back side A to the crotch C, or may be arranged from the abdomen B to the crotch C, or the crotch it may be disposed only in C.

  Further, the present invention can be applied to a pants-type disposable diaper previously formed into a pant-type in addition to a deployable disposable diaper having a fastening tape as in the above-described embodiment, and further, a sanitary napkin, an incontinence pad, etc. It can also be applied to.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to such examples.

[Example 1]
An unfolded disposable diaper having the same basic configuration as the diaper 1 shown in FIGS. 1 and 2 was produced and used as a sample of Example 1. As the surface sheet, there are a convex portion and a concave portion that have an upper layer directed to the wearer's skin side and a lower layer disposed on the absorber side, and project toward the wearer's skin side on the skin facing surface of the surface sheet. A concavo-convex surface sheet having a two-layer structure formed in large numbers was used. As an upper layer and a lower layer in the two-layer uneven surface sheet, a liquid-permeable air-through nonwoven fabric having a basis weight of 18 g / m ² was used, and the upper layer was provided with unevenness by embossing. A thing was used. The basis weight of the upper layer after providing the irregularities was 23.5 g / m ² . In the uneven surface sheet having a two-layer structure, the upper layer having unevenness and the lower layer not having unevenness are partially bonded to each other at the bottoms of a large number of recesses, and the bottoms of the recesses are formed between the upper layer and the lower layer. It is a junction. Moreover, the upper layer protrudes toward the wearer's skin side at a portion other than the bottom portion (joint portion) of the concave portion to form a convex portion, and a space is formed in the convex portion. As the back sheet, a liquid-impermeable and moisture-permeable polyethylene resin film (containing calcium carbonate) having a basis weight of 20 g / m ² was used. The absorbent core, as those obtained by holding the particulate water-absorbing polymer in the fiber aggregate, fluff pulp 200 g / m ² and the water-absorbing polymer 186 g / m ² total basis consisting homogeneous mixture of a weight 386 g / m ² An absorbent core was used. The total length of the absorbent core in the longitudinal direction was 360 mm, and the total length in the width direction (maximum length) was 110 mm. As described above, the slit is formed by using the predetermined mold so that the absorbent core forming material is not intentionally deposited on the predetermined portion during manufacturing of the absorbent core. In the cross-sectional view in the width direction as shown, it has a trapezoidal shape (equal legs), and the width gradually increases from the skin facing surface side toward the non-skin facing surface side in the entire area of the slit. As the core wrap sheet, a liquid-permeable mount having a basis weight of 13.5 g / m ² was used.

[Comparative Example 1]
In Example 1, an unfolded disposable diaper was produced in the same manner as in Example 1 except that no slit was formed in the absorbent core, and a sample of Comparative Example 1 was obtained.

[Comparative Example 2]
The absorbent core which does not have a slit was manufactured similarly to the comparative example 1, and the predetermined site | part of this absorbent core was compressed in the thickness direction by well-known embossing, and the slit was formed. In the absorbent core thus formed, the portion facing the opening of the slit (the opening facing portion) is consolidated and has a higher density than the peripheral portion. Further, the slit has a rectangular shape in a cross-sectional view in the width direction as shown in FIG. 2, and the width of the slit does not change in the thickness direction of the absorbent core in the entire area of the slit. Except for the above points, an unfolded disposable diaper was produced in the same manner as in Example 1, and used as a sample of Comparative Example 2.

[Comparative Example 3]
In Example 1, the slit of the absorbent core is a through-type slit that penetrates the absorbent core in the thickness direction, and the absorbent core that does not have the opening facing portion is used. Similarly, an unfolded disposable diaper was prepared and used as a sample of Comparative Example 3.

[Evaluation]
About each sample (disposable diaper) of an Example and a comparative example, according to the following method, bending rigidity, wetback amount, and urine absorption time were evaluated. The results are shown in Table 1 below.

<Bending rigidity>
The bending stiffness of the measurement sample was measured using a handle meter. The smaller the measured value of the handleometer, the easier it is for the measurement sample to bend (the above-mentioned bending deformation with the slit as a fold curve is likely to occur), and it indicates that it is flexible and easy to install and has good fit. The method for measuring the bending stiffness with the handle-ometer is as follows. A three-dimensional gather is removed from the sample diaper to prepare a measurement sample having the same width as that of the absorber, and the measurement sample is placed on a support table of a handle-ometer having a groove having a width of 20 mm. It arrange | positions so that a direction may be orthogonal to this groove | channel. Then, the center of the measurement sample (absorber) is pushed with a blade having a thickness of 2 mm, and the force required for the measurement sample to be bent is measured. The average value at the center of the measurement sample is taken as the measurement value. As the handle oh meter, Daiei Kagaku Seiki Seisakusho, a texture tester (handle oh meter method), and HOM-3 type can be used.

<Wetback amount and urine absorption time>
Spread the disposable diaper flat, place the acrylic sheet with the cylindrical injection part on the surface sheet of the diaper, with the top sheet facing up and fixed on the horizontal surface, and then place a weight on the acrylic sheet A load of ² kPa (20 gf / cm ² ) was applied to the absorber portion. The injection part provided in the acrylic plate has a cylindrical shape (height 53 mm) with an inner diameter of 36 mm. The acrylic plate has a cylindrical part of the cylindrical injection part at a third portion in the longitudinal direction and the central axis in the width direction. A through hole having an inner diameter of 36 mm is formed so that the central axes coincide with each other and communicates between the inside of the cylindrical injection portion and the surface sheet facing surface of the acrylic plate. The core wrap sheet covering the diaper's absorbent core is placed so that the central axis of the cylindrical injection portion of the acrylic plate comes to a position 123 mm from the tip of the ventral portion in the longitudinal direction of the core wrap sheet, and 30 g of artificial urine is injected. Absorbed and allowed to stand for 10 minutes, and then 30 g of artificial urine was injected and absorbed. Such an artificial urine injection operation was repeated three times, and a total of 90 g of artificial urine was absorbed in the diaper. Next, 20 sheets of 4A filter paper made by Toyo Roshi Kaisha, Ltd (10 cm × 10 cm) are superimposed on the artificial urine absorption site in the diaper, and a load is further applied for 2 minutes on the filter paper to absorb the artificial urine absorbed in the diaper. Absorbed. The load was such that 3.5 kg was applied to an area of 10 cm × 10 cm. After 2 minutes, the load was removed, and the weight of the filter paper that absorbed artificial urine was measured. The weight of the filter paper before artificial urine absorption was subtracted from this weight, and the value was taken as the wetback amount. In the measurement of the wetback amount, the third artificial urine injection time (the time from the start of injection until the entire amount was absorbed into the diaper) was defined as the urine absorption time. The smaller the wetback amount and the shorter the urine absorption time, the better the excretion fluid absorbability and the higher the evaluation.

  As it follows the composition of the artificial urine. 1.94% by mass of urea, 0.7954% by mass of sodium chloride, 0.11058% by mass of magnesium sulfate (septahydrate), 0.06208% by mass of calcium chloride (dihydrate), 0.19788% by mass of potassium sulfate , Polyoxyethylene lauryl ether 0.0035 mass% and ion-exchanged water (remaining amount).

  As is clear from the results shown in Table 1, the disposable diaper of the example has a smaller wetback amount and shorter urine absorption time than the disposable diapers of each comparative example, and has a low bending rigidity and is soft so that it fits. Is a good absorbent article. The disposable diaper of Comparative Example 1 is mainly formed with no slits in the absorbent core, so it has poor liquid permeation / diffusion function for excretory fluids, and therefore has a large wetback amount and a long urine absorption time. Because it cannot cause bending deformation with a bending curve, it has high bending rigidity and poor flexibility and fit. The disposable diaper of Comparative Example 2 has a slit formed in the absorbent core, but the sectional view shape in the width direction of the slit is a rectangular shape, and the width is invariant in the thickness direction of the absorbent core. High bending rigidity and poor flexibility and fit. In addition, in the disposable diaper of Comparative Example 2, the opening facing portion is consolidated because the slit is formed by embossing, so that bending deformation with the slit as a fold line hardly occurs, Since the liquid diffusion tends to be delayed at the opening facing portion having a higher density than the peripheral portion, the wetback amount is large and the urine absorption time is long. In the disposable diaper of Comparative Example 3, the slit formed in the absorbent core is a penetration type, so the urine absorption time is short (the urine absorption rate is fast), but the wetback amount is large and the excretory fluid absorbability is good It's hard to say. From the above, it is possible to form a non-penetrating slit in the absorbent core and to make the cross-sectional shape in the width direction of the slit trapezoidal, and not to consolidate the opening facing portion of the slit. It turns out that it is effective in aiming at the improvement of both a fitting property and a leak prevention property.

1 disposable diaper (absorbent article)
2 Top sheet 3 Back sheet 4, 4 A Absorber 5, 5 A, 5 B Slit 40 Absorbent core 40 a Absorbent core skin facing surface 40 b Absorbent core non-skin facing surface 40 c Core material deposit 41 Core wrap sheet 50 Aperture

Claims (3)

An absorbent article comprising an absorbent core,
In the absorbent core, the slit does not penetrate the absorbent core in the thickness direction and has an opening on the skin facing surface side or the non-skin facing surface side of the absorbent core, and the slit is in the longitudinal direction of the absorbent article. Formed to extend,
The slit has a portion in which the width of the slit gradually increases or decreases from the skin facing surface side of the absorbent core toward the non-skin facing surface side, and the width of the slit is relatively wide. An absorbent article having the opening of the slit on the side.   The absorbent article according to claim 1, wherein the slits are continuous linear slits, and a plurality of slits are formed at predetermined intervals in a lateral direction of the absorbent article.   The absorbent article according to claim 1 or 2, wherein a portion of the absorbent core adjacent to the slit in the thickness direction of the absorbent core is not consolidated.

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