JP6251558B2 - Absorbent articles - Google Patents

Description

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

  As an absorbent article such as a disposable diaper, an absorbent article that absorbs and holds excreted bodily fluid and has a longitudinal direction corresponding to the wearer's front-rear direction and a lateral direction orthogonal thereto is known. In general, the absorbent body is formed by dispersing particles of a water-absorbing polymer composed of a crosslinked polyacrylate or the like in pulp fibers. In such an absorbent body, the water-absorbing polymer is fixed at a predetermined site, and thus excreted body fluid is absorbed and held only after reaching the water-absorbing polymer fixing portion. Therefore, when high-viscosity fluid such as loose stool or blood with a relatively low permeation / diffusion rate is excreted, only a part of the high-viscosity fluid reaches the water-absorbing polymer fixing part, and the rest is fixed to the water-absorbing polymer. It may take time for all of the high-viscosity body fluid to reach the water-absorbing polymer fixing portion and be absorbed and held, and liquid leakage may occur during that time.

  Therefore, in Patent Document 1, a polysaccharide capable of thickening in the presence of a polyvalent metal ion is contained in the absorbent body of the absorbent article, and the polysaccharide is dissolved in water in body fluids or excreta. It is described that it exists in a dissociable state. In Patent Document 1, as a specific example of such a configuration, the polysaccharide powder is uniformly dispersed throughout the planar direction and the thickness direction of the absorbent body in an absorbent body mainly composed of pulp fibers. It is described.

  Further, in the absorbent article, only a part of the absorbent body (particularly the part facing the body fluid excretion part of the wearer and the vicinity thereof) is used for absorbing and holding the body fluid, and the other part may be hardly used. There was room for improvement in terms of effective use of the entire absorber. For example, in Patent Document 2, when a wearer urinates while wearing a disposable diaper, the absorbent body is crushed by a body pressure load, and absorption of urine stops at the body pressure load position. In view of the inconvenience that the entire absorber is not effectively used, it is described that the absorber has a configuration in which the absorbent material and the spiral flexible member are alternately arranged in the lateral direction (width direction) of the diaper. . This spiral flexible member is a spiral body made of a flexible metal or thermoplastic resin, and does not substantially contain an absorbent material.

  Patent Document 3 discloses a disposable diaper capable of minimizing diffusion of bodily fluids such as soft stool and preventing liquid leakage, and provided with a stool pocket for storing and holding bodily fluids in an absorbent body containing a water-absorbing polymer. In the portions other than the pockets, the water-absorbing polymer is unevenly distributed on the skin facing surface side, and in the stool pocket, the water-absorbing polymer is unevenly distributed on the peripheral wall portion and the bottom surface portion.

JP 2010-148923 A JP 2003-79654 A JP 2007-117727 A

  Effective use of the entire absorbent body in the absorbent article leads to prevention of liquid leakage and is an important technical problem. For effective use of the entire absorbent body, it is necessary to suppress diffusion of body fluid in the lateral direction and promote diffusion in the longitudinal direction. However, Patent Document 2 discloses that the liquid diffusion in the vertical direction is promoted in the absorber, but no contrivance is made for the liquid diffusion in the horizontal direction, and there is a possibility that liquid leakage (lateral leakage) may occur. there were. Patent Document 1 discloses a technique for suppressing diffusion in both the vertical direction and the horizontal direction. In this case, liquid diffusion is not promoted in either direction, and the entire absorber is effectively used. It was not possible to use it. There is room for improvement in a technique that can appropriately control the diffusibility of body fluid in the absorbent body and effectively prevent leakage of body fluid.

  Therefore, the subject of this invention is related with the absorptive article which the diffusibility of a bodily fluid is controlled appropriately, and does not produce liquid leak easily.

  The present invention comprises an absorptive core that absorbs and holds excreted body fluid, and is provided on the abdomen side of the wearer, the dorsal side part arranged on the dorsal side, and a crotch part positioned therebetween. And an absorbent article having a longitudinal direction extending from the abdominal side portion to the back side portion via the crotch portion and a transverse direction perpendicular thereto, wherein the absorbent core is the absorbent core A polysaccharide having an opening on the skin-facing surface and extending in the longitudinal direction, and a polysaccharide that can adsorb a body fluid in at least part of the thickness direction of the absorbent core adjacent to the groove. A saccharide-containing region, and a polysaccharide-free region in which the polysaccharide is not contained over the entire thickness direction of the absorbent core, and in the crotch part, all the groove portions of the absorbent core Of the absorbent core being farthest from the longitudinal center line that bisects the absorbent core in the lateral direction Laterally outwardly of the outer groove, there is provided an absorbent article wherein the polysaccharide-containing region adjacent to said lateral outermost groove is disposed.

  ADVANTAGE OF THE INVENTION According to this invention, the diffusibility of a bodily fluid is controlled appropriately, and the absorbent article which does not produce a liquid leak easily is provided.

FIG. 1 is a perspective view schematically showing a pants-type disposable diaper that is an embodiment of the absorbent article of the present invention. FIG. 2 is a developed plan view schematically showing a partially broken skin facing surface side in the developed and extended state of the diaper shown in FIG. FIG. 3 is an exploded perspective view schematically showing the diaper shown in FIG. 1. FIG. 4 is a plan view schematically showing the non-skin facing surface side of the absorbent core constituting the diaper shown in FIG. 1. FIG. 5 is a cross-sectional view schematically showing a cross section (cross section) taken along the line II of FIG. FIG. 6 is a plan view (corresponding to FIG. 4) schematically showing the non-skin facing surface side of the absorbent core used in the examples. 7 is a cross-sectional view schematically showing an example of a cross section (transverse cross section) taken along line II-II in FIG. FIG. 8 is a cross-sectional view schematically showing another example of the cross section (transverse cross section) taken along the line II-II in FIG.

  The present invention will be described below based on preferred embodiments with reference to the drawings. The pants type disposable diaper 1 which is one Embodiment of the absorbent article of this invention is described by FIGS. 1-3. The diaper 1 includes an absorbent core 23 that absorbs and holds excreted bodily fluids, and in the wearing state, the abdominal side A disposed on the abdomen side of the wearer, the back side C disposed on the back side, and those The crotch part B is located between the crotch part B and is disposed in the wearer's crotch part, and has a vertical direction X and a horizontal direction Y orthogonal thereto. The longitudinal direction X of the diaper 1 is a direction that extends between the abdominal side A and the back side C via the crotch B. The crotch part B is a region in which concave openings (leg edges 10, 10) for forming leg openings LH, LH are formed at both side edges along the longitudinal direction X of the outer package 3, and the absorbent core This is a region including the central portion of the vertical direction X when 23 is divided into three equal parts in the vertical direction X.

  The diaper 1 includes an absorbent main body 2 and an exterior body 3 that is disposed on the non-skin facing surface side of the absorbent main body 2 and fixes the absorbent main body 2. The outer package 3 forms the outer shape of the diaper 1 in the unfolded and extended state of the diaper 1 as shown in FIG. 2, and the peripheral edge of the outer package 3 forms the outline of the diaper 1 in that state. The “expanded and extended state” of the diaper 1 means that the diaper 1 is separated by a side seal portion to be in an expanded state, and the expanded state of the diaper 1 is extended by the elastic member of each part to eliminate the influence of the elastic member. In this state, it is expanded until it becomes the same size as when expanded in a flat shape. In the present specification, the skin-facing surface is a surface (side closer to the wearer's skin) that faces the wearer's skin in the wearing state in the diaper 1 and its constituent members (for example, the absorbent core 23). The skin facing surface is a surface (a side farther from the skin than the skin facing surface) directed toward the opposite side of the skin side of the wearer in the wearing state in the diaper 1 and its constituent members.

  As shown in FIG. 2, the absorbent main body 2 has a rectangular shape that is long in the same direction as the longitudinal direction X of the diaper 1. The absorbent main body 2 is bonded to the central portion of the outer package 3 with an adhesive so that the longitudinal direction thereof coincides with the longitudinal direction X of the diaper 1 in the expanded and extended state. The absorbent main body 2 includes a liquid-permeable surface sheet 21 that forms a skin facing surface, a liquid-impermeable or liquid-permeable or water-repellent back sheet 22 that forms a non-skin facing surface, and both sheets 21 and 22. It has a liquid-retaining absorbent core 23 interposed therebetween. The absorptive core 23 is covered with a liquid-permeable core wrap sheet (not shown) such as paper or nonwoven fabric at least on the skin facing surface and non-skin facing surface and the side end surface along the longitudinal direction X. An absorbent body composed of the conductive core 23 and a core wrap sheet covering the core 23 is formed. The absorptive main body 2 is formed by integrating the absorber, the top sheet 21 and the back sheet 22 by a known joining means such as an adhesive. As the top sheet 21 and the back sheet 22, various types conventionally used for this type of absorbent article can be used without particular limitation. For example, various nonwoven fabrics or apertured films can be used as the top sheet 2, and a resin film, a laminate of a resin film and a nonwoven fabric, or the like can be used as the back sheet 3.

  As the absorbent core 23, a fiber aggregate made of a fiber material mainly composed of hydrophilic fibers such as wood pulp and hydrophilized synthetic fibers, or a particulate water-absorbing polymer is held in the fiber aggregate. Can be used. This fiber assembly is obtained by stacking fiber materials using a known fiber stacking apparatus. As the water-absorbing polymer, those usually used in this type of absorbent article can be used without particular limitation, and examples thereof include those containing sodium polyacrylate as a main component.

  On the left and right sides along the longitudinal direction X of the skin facing surface of the absorbent main body 2, as shown in FIG. 2, side cuffs 24, 24 made of a liquid-resistant or water-repellent and breathable sheet material are provided. Is provided. In the vicinity of the free end of each side cuff 24, one or more thread-like side cuff elastic members 25 are arranged in an extended state. Each side cuff 24 stands up when the side cuff elastic member 25 arranged in the stretched state contracts in the wearing state of the diaper 1 and prevents the liquid from flowing out to the side.

  As shown in FIG. 2, the exterior body 3 has a pair of leg edge portions 10 and 10 whose both side edges along the longitudinal direction X are curved inwardly in the crotch portion B to form an inward arc shape. When viewed from above, the central region in the vertical direction X has an hourglass shape that is bound inward in the horizontal direction Y. The exterior body 3 has both side edges A1 and A2 along the longitudinal direction X in the ventral side A and both side edges C1 and C2 along the longitudinal direction X in the back side C. The adhesive, heat seal, and ultrasonic seal As shown in FIG. 1, a pair of side seal portions S and S are formed in the diaper 1, and the waist opening WH and the pair of leg openings are joined together. Portions LH and LH are formed.

  As shown in FIG. 3, the exterior body 3 includes a laminated body of an outer layer sheet 31 and an inner layer sheet 32. In the wearing state of the diaper 1, the outer layer sheet 31 is located on the side far from the wearer's body, forms a non-skin facing surface (outer surface) of the diaper 1, and the inner layer sheet 32 is located on the side closer to the wearer's body. And the skin opposing surface (inner surface) of the diaper 1 is formed. The outer layer sheet 31 and the inner layer sheet 32 are adjacent to each other in the thickness direction. The outer layer sheet 31 and the inner layer sheet 32 are joined by an adhesive at a predetermined site. In addition to the same shape and the same size as the inner layer sheet 32, the outer layer sheet 31 is further outward from the end in the longitudinal direction X on the ventral side A side of the inner layer sheet 32 when the sheets 31, 32 are laminated. And a dorsal extension part 31E extending outward from the end in the longitudinal direction X on the dorsal side C side of the inner layer sheet 32. As shown in FIG. 2, the extending portions 31 </ b> E and 31 </ b> E of the outer layer sheet 31 respectively cover the inner layer sheet 32 so as to cover both ends in the longitudinal direction X of the absorbent main body 2 arranged and fixed on the inner layer sheet 32. Folded to the side and fixed to the other constituent members (inner layer sheet 32, absorbent main body 2, side cuffs 24) of the diaper 1 facing both the extending portions 31E, 31E by an adhesive. As the outer layer sheet 31 and the inner layer sheet 32, various types conventionally used as an exterior body in this type of absorbent article can be used without particular limitation. For example, nonwoven fabrics (spunbond nonwoven fabrics, Air through nonwoven fabric, needle punched nonwoven fabric, etc.).

  As shown in FIG. 2, one or a plurality of waist elastic members 11 for forming waist gathers are arranged in a stretched state in the lateral direction Y in the waist portion D in each of the ventral portion A and the back portion C. Yes. The waist elastic member 11 extends over substantially the entire length in the lateral direction Y of the waist portion D. The waist part D is a part located around the waist of the wearer, and is generally the entire length in the longitudinal direction X of the diaper 1 from the end in the longitudinal direction X on the abdomen side A side or the back side part C side of the diaper 1. It is an area up to a length of 1 to 15%. Thereby, an annular waist gather substantially continuous over the entire circumference is formed in the waist opening WH (see FIG. 1).

  In addition, as shown in FIG. 2, one or a plurality of leg elastic members 12 for forming leg gathers are stretched on both side portions (leg edge portions) 10, 10 along the longitudinal direction X of the crotch B. It is arranged with. As a result, an annular leg gather substantially continuous over the entire circumference is formed on the leg edge 10 which is the opening edge of each of the pair of leg openings LH and LH (see FIG. 1). The leg elastic member 12 is arranged in an extended state so that elastic stretchability is expressed at a portion outside in the lateral direction Y from at least both side edges along the longitudinal direction X of the absorbent main body 2, and absorbency At least the central part in the lateral direction Y of the part where the main body 2 exists is not arranged in a state where the elastic stretchability is expressed.

  Further, as shown in FIG. 2, apart from these elastic members 11, 12, in the waist part E located between the waist part D and the crotch part B in the abdominal part A and the back part C, respectively. The waist elastic member 13 for forming one or a plurality of waist circumference gathers is arranged in an extended state in the lateral direction Y. The waist elastic member 13 is arranged in an extended state so that elastic stretchability is expressed at least in the outer portion in the lateral direction Y from both side edges along the longitudinal direction X of the absorbent main body 2 and absorbs the waist. The elastic main body 2 is not disposed at least in the central portion in the lateral direction Y in a state where the elastic stretchability is expressed.

  Each of the elastic members 11, 12, and 13 is sandwiched and fixed between the outer layer sheet 31 and the inner layer sheet 32 constituting the exterior body 3 by a bonding means such as an adhesive. Each of the elastic members 11, 12, and 13 is formed by forming a stretchable material such as natural rubber, polyurethane resin, foamed urethane resin, or hot-melt stretchable member into a thread shape (thread rubber) or a belt shape (flat rubber). Preferably used.

  The absorbent core 23 with which the diaper 1 is provided is shown by FIG.4 and FIG.5. The absorbent core 23 has a rectangular shape in plan view as shown in FIG. 4, and has a single layer structure as shown in FIG. As one of the main features of the diaper 1 of the present embodiment, the absorbent core 23 has an opening on the skin facing surface of the absorbent core 23 and extends in the longitudinal direction X, and is adjacent to the groove 4. And at least a part of the absorbent core 23 in the thickness direction, the polysaccharide-containing region 5 containing a polysaccharide capable of thickening a body fluid, and the entire area of the absorbent core 23 in the thickness direction. The point which has the polysaccharide non-containing area | region 6 in which the polysaccharide is not contained is mentioned. The polysaccharide-containing region 5 adjacent to the groove 4 and the groove 4 are directly adjacent to each other, and the polysaccharide-free region 6 is not disposed between them. Reference numeral 50 in the figure indicates a portion where the polysaccharide is present. The polysaccharide-containing region 5 consists of the polysaccharide existing part 50 alone or includes the polysaccharide existing part 50 in part. Details of the polysaccharide will be described later.

  In this embodiment, the groove part 4 is a through-hole which penetrates the absorptive core 23 in the thickness direction, as shown in FIG. 5, and no material for forming the absorptive core 23 exists in the groove part 4. Therefore, the groove part 4 has an opening not only on the skin facing surface of the absorbent core 23 but also on the non-skin facing surface located on the opposite side. However, the groove part which concerns on this invention is not restrict | limited to such a through-hole, and has an opening part only in a skin opposing surface (it does not have an opening part in a non-skin opposing surface), and an absorptive core It may be a thin-walled portion that is thinner than other portions.

  Regardless of whether it is a through-hole or a thin-walled portion, the groove portion according to the present invention can be formed in the same manner as the groove portion in this type of absorbent core. For example, i) Embossing (thin-walled) at a predetermined portion of the absorbent core Part), post-processing such as die-cutting, cutting, etc., to completely remove the absorbent core forming material at the predetermined site (in the case of through-holes) or partly (in the case of thin-walled parts) Ii) When an absorbent core is manufactured using a known fiber stacking apparatus, the absorbent core is formed by a method of intentionally limiting the amount of the formed material stacked at a predetermined site in the forming material stacking process. be able to. In the case where the groove portion according to the present invention is a thin-walled portion, the thin-walled portion formed by the method i) is compressed in the thickness direction by post-processing, so that it is higher than other portions of the absorbent core. In contrast to the density, the thin part formed by the method ii) is not consolidated in the formation process, and therefore has a density comparable to other parts of the absorbent core.

  In the present embodiment, the absorbent core 23 is provided with two slit-like groove portions 4 in a line-of-view (rectangular shape). The two grooves 4 and 4 are divided and arranged on one side and the other side with reference to a longitudinal center line 23L that bisects the absorbent core 23 in the lateral direction. The groove 4 on the side is symmetrical. Both the groove parts 4 and 4 are arranged at least in the crotch part B, and the central part in the vertical direction X when the absorbent core 23 is equally divided into three in the vertical direction X (the central part in the vertical direction X of the crotch part B). In FIG. 3, the central portion extends over the entire length in the longitudinal direction X.

  In the present embodiment, in the crotch part B (the central part in the longitudinal direction X when the absorbent core 23 is equally divided into the longitudinal direction X), the absorption of all the grooves 4 included in the absorbent core 23. A polysaccharide-containing region 5 is disposed on the outer side in the lateral direction Y of the laterally outermost groove portion 4 that is farthest from the longitudinal center line 23L of the conductive core 23 and adjacent to the laterally outermost groove portion 4. ing. Hereinafter, the “polysaccharide-containing region 5 located outside the laterally outermost groove portion 4 in the lateral direction Y and adjacent thereto” is also referred to as “laterally outermost polysaccharide-containing region 51”. In the present embodiment, as described above, the two groove portions 4 and 4 are symmetrical with respect to the vertical center line 23L, and there is no difference in the distance between the groove portions 4 and 4 from the vertical center line 23L. Therefore, both the groove portions 4 and 4 are “lateral outermost groove portions”. The present invention includes a form in which the absorbent core 23 has only one groove part 4. In such a form, the single groove part 4 overlaps the vertical center line 23. However, the one groove portion 4 is a “lateral outermost groove portion”.

According to the diaper 1 of this embodiment, the groove part 4, the polysaccharide containing area | region 5, and the polysaccharide non-containing area | region 6 are appropriately arrange | positioned by the absorptive core 23 to the vertical direction X of the excreted body fluid. And the diffusion of the body fluid in the lateral direction Y is suppressed. As a result, the entire absorbent core 23 is effectively used, and the leakage of the body fluid is effectively prevented.
That is, since the absorbent core 23 is provided with the groove 4 extending in the longitudinal direction X through the crotch B, body fluid such as urine excreted in the crotch B is absorbed through the groove 4. Since the inside of the core 23 is diffused in the longitudinal direction X and easily moves to the abdominal part A and the dorsal part C, the proportion of the part used for absorbing and holding body fluid in the absorbent core 23 is improved, and the absorbency is increased. Effective utilization of the entire core 23 is achieved. That is, the groove part 4 functions as a liquid conduit for excreted body fluid.
Moreover, since the excreted body fluid is thickened by contacting the polysaccharide contained in the region 5 in the polysaccharide-containing region 5 adjacent to the groove portion 4 in the lateral direction Y, the fluid is moved in the lateral direction Y. Is effectively suppressed, thereby effectively preventing leakage of body fluid from the side of the absorbent core 23 (so-called side leakage).
Further, the fact that the polysaccharide-containing region 5 is adjacent to the groove 4 in the lateral direction Y is effective not only for suppressing diffusion of body fluid in the lateral direction Y but also for promoting diffusion in the longitudinal direction X. In other words, the excreted body fluid is suppressed from being diffused in the lateral direction Y by the polysaccharide-containing region 5, while the diffusion in the longitudinal direction X is promoted by the grooves 4 during the suppression of the diffusion.

  In particular, in the present embodiment, as shown in FIG. 5, the laterally outermost polysaccharide-containing region 51 (the laterally outermost groove portion 4 is located on the outer side in the lateral direction Y and is adjacent thereto. In the saccharide-containing region 5), since the polysaccharide is contained throughout the thickness direction of the absorbent core 23, it is excellent in the effect of preventing diffusion of the body fluid in the lateral direction Y by the region 51, and more effectively prevents side leakage. Can be prevented.

  In the present embodiment, the polysaccharide-containing region 5 has a plurality of (two) in a plan view of the non-skin facing surface 23b (surface relatively close to the back sheet 22) of the absorbent core 23 as shown in FIG. The groove portions (laterally outermost groove portions) 4 and 4 are arranged around each of the groove portions 4 and 4, and each groove portion 4 is surrounded by the polysaccharide-containing region 5. That is, the polysaccharide-containing region 5 is arranged over the entire length in the longitudinal direction X of each groove portion 4 on each side in the lateral direction Y of each groove portion 4, and further, the groove portion 4 in the longitudinal direction X in the absorbent core 23. The part which is not arranged (the part located in the ventral part A and the dorsal part C) is also arranged adjacent to the groove part 4.

  The absorbent core 23 has a groove portion 26 sandwiched between two groove portions 4, 4 at the central portion in the lateral direction Y of the crotch B, and the groove portion 26 is adjacent to the groove portion 4. A polysaccharide-containing region 5 is arranged. More specifically, the groove gap portion 26 of the absorbent core 23 includes a pair of polysaccharide-containing regions 5 and 5 adjacent to the groove portions 4 and 4 located on both sides in the lateral direction Y, and both the regions 5 and 5. It is comprised including the polysaccharide non-containing area | region 6 located in between.

  And in the polysaccharide content area | region 5 of the groove part gap part 26, as shown in FIG. 5, the polysaccharide is not contained in the whole area of the thickness direction, and the non-skin opposing surface 23b side of the absorptive core 23 is provided. It is unevenly distributed. The skin facing surface 23a in the groove gap portion 26 located in the central portion of the crotch B in the lateral direction Y is usually a portion that first receives the excreted body fluid, and the skin facing surface 23a side in the groove gap portion 26 is If polysaccharides are contained in the body, the diffusion action of the body fluid in the longitudinal direction X by the groove 4 may be inhibited. Therefore, with respect to the groove gap portion 26, the polysaccharide is unevenly distributed on the non-skin facing surface 23b side that is located on the side opposite to the skin facing surface 23a, thereby inhibiting the diffusion of the body fluid in the vertical direction X. Therefore, the diffusion of the body fluid in the lateral direction Y can be more reliably suppressed.

  From the viewpoint of more surely exhibiting such operational effects, in the polysaccharide-containing region 5 of the groove gap portion 26, the thickness T1 of the polysaccharide existing portion 50 that is unevenly distributed on the non-skin facing surface 23b side (see FIG. 5). Is preferably 1% or more, more preferably 5% or more, and preferably 70% or less, more preferably 50% or less, more specifically, with respect to the thickness of the polysaccharide-containing region 5 (groove gap portion 26). Is preferably 1 to 70%, more preferably 5 to 50%.

  As shown in FIGS. 4 and 5, the laterally outermost polysaccharide-containing region 51 (the polysaccharide-containing region 5 located outside the laterally outermost groove portion 4 in the lateral direction Y and adjacent thereto) ) In the lateral direction Y, a polysaccharide-free region 6 is disposed adjacent to the region 51. That is, the portion of the absorbent core 23 that is located outward in the lateral direction Y from the laterally outermost groove portion 4 is the polysaccharide-containing region 5 (laterally outermost portion) from the inner side to the outer side in the lateral direction Y. The polysaccharide-containing region 51) and the polysaccharide-free region 6 are arranged in this order, and the side edge along the lateral direction Y of the absorbent core 23 is not the polysaccharide-containing region 5, It is formed from the polysaccharide non-containing region 6. In the present embodiment, as shown in FIG. 4, not only the side edge along the lateral direction Y of the absorbent core 23 but also the entire peripheral edge of the absorbent core 23 is formed from the polysaccharide-free region 6. . With such a configuration, the body fluid exceeding the region 5 can be absorbed and held in the polysaccharide-free region 6 while being thickened in the polysaccharide-containing region 5, and leakage is effectively prevented.

  In the present embodiment, as shown in FIG. 4, the groove 4 is not open to the longitudinal ends 23 </ b> E and 23 </ b> E of the absorbent core 23, and the closed end 4 </ b> E is provided at each of the longitudinal front and rear ends. have. As described above, the groove portion 4 functions as a liquid conduit for excreted body fluid, and the groove portion 4 having such a function extends over the entire length of the absorbent core 23 in the longitudinal direction X. If the absorbent core 23 is open to the longitudinal ends 23E, 23E, there is a concern that body fluid that has passed through the groove 4 leaks from the longitudinal ends 23E, 23E. However, as in the present embodiment, the groove Such a concern can be wiped off more reliably by having the closed end 4E at each of the front and rear ends in the length direction of 4.

  Further, in the present embodiment, as shown in FIG. 4, the polysaccharide-containing region 5 and the polysaccharide-containing region 5 are formed outwardly in the longitudinal direction X of the closed end 4E of the groove portion 4 from the inside in the longitudinal direction X to the outside. The saccharide-free region 6 is arranged in this order, and both regions 5 and 6 are adjacent to each other. As described above, the polysaccharide-containing region 5 is disposed on the outer side in the longitudinal direction X of the closed end portion 4E of the groove portion 4 so as to be adjacent to the closed end portion 4E. The body fluid diffused in the longitudinal direction X can be thickened in the region 5, thereby effectively preventing leakage of the body fluid from the longitudinal end 23 </ b> E of the absorbent core 23.

  In the polysaccharide-containing region 5 located outward in the longitudinal direction X from the closed end portion 4E of the groove portion 4, the polysaccharide is in the thickness direction of the absorbent core 23 as in the laterally outermost polysaccharide-containing region 51. Or may be unevenly distributed on the non-skin facing surface 23b side of the absorbent core 23 as in the polysaccharide-containing region 5 of the groove gap 26. However, in the region of the absorbent core 23 located outside the closed end 4E of the groove 4 in the longitudinal direction X, the diffusion of the body fluid in the longitudinal direction X is not so important. Since it is more important to prevent leakage of body fluid from the longitudinal end 23E, in the polysaccharide-containing region 5 arranged in the region, the polysaccharide is in the thickness direction of the absorbent core 23. It is preferable to contain in the whole area.

From the viewpoint of ensuring the above-described effects of the groove portion 4, the polysaccharide-containing region 5 and the polysaccharide-free region 6, the dimensions and the like of each part of the absorbent core 23 are set as follows. It is preferable.
The width W1 of the groove 4 (see FIG. 4; the length in the direction perpendicular to the length direction of the groove 4) is preferably 3 mm or more, more preferably 5 mm or more, and preferably 20 mm or less, more preferably 15 mm or less. More specifically, the thickness is preferably 3 to 20 mm, and more preferably 5 to 15 mm.
The total length in the longitudinal direction X of the groove part 4 is preferably 60% or more, more preferably 70% or more, and preferably 95% or less, more preferably 90% with respect to the total length in the longitudinal direction X of the absorbent core 23. Hereinafter, more specifically, it is preferably 60 to 95%, and more preferably 70 to 90%.
The width of the groove part 26 (the interval between the two groove parts 4 and 4) is preferably 60 mm or more, more preferably 70 mm or more, and preferably 100 mm or less, more preferably 90 mm or less, more specifically preferably Is 60 to 100 mm, more preferably 70 to 90 mm.

The width W2 (see FIG. 4) of the polysaccharide-containing region 5 (laterally outermost polysaccharide-containing region 51) adjacent to the groove 4 in the lateral direction Y is preferably 5 mm or more, more preferably 7.5 mm or more. And, it is preferably 20 mm or less, more preferably 15 mm or less, more specifically preferably 5 to 20 mm, more preferably 7.5 to 15 mm.
The width W3 (see FIG. 4) of the polysaccharide-containing region 5 adjacent to the groove 4 in the longitudinal direction X is preferably 5 mm or more, more preferably 7.5 mm or more, and preferably 20 mm or less, more preferably 15 mm. Hereinafter, more specifically, it is preferably 5 to 20 mm, and more preferably 7.5 to 15 mm.
The distance between the closed end 4E of the groove 4 and the longitudinal end 23E of the absorbent core 23 (the longitudinal end 23E, 23E of the absorbent core 23 that is relatively close to the closed end 4E) is: The thickness is preferably 10 mm or more, more preferably 15 mm or more, and preferably 30 mm or less, more preferably 25 mm or less, more specifically preferably 10 to 30 mm, and more preferably 15 to 25 mm.

The thickness of the absorbent core 23 is preferably 2 mm or more, more preferably 2.5 mm or more, and preferably 10 mm or less, more preferably 8 mm or less, more specifically preferably 2 to 10 mm, and more preferably 2 mm. .5 to 8 mm.
The basis weight of the absorbent core 23 is preferably 100 g / m ² or more, more preferably 200 g / m ² or more, and preferably 500 g / m ² or less, more preferably 400 g / m ² or less, more specifically , Preferably 100 to 500 g / m ² , more preferably 200 to 400 g / m ² .

  The polysaccharide used in the present invention can thicken a contacted body fluid (water), and the body fluid includes a low viscosity solution such as urine and a high viscosity solution such as soft stool and blood. Whether or not the polysaccharide can thicken the body fluid is determined according to the thickening evaluation method described below. That is, when the polysaccharide to be evaluated is added to 500 ml of a calcium chloride aqueous solution containing 0.1% by mass of calcium ions so that the concentration of the polysaccharide after addition is 0.2% by mass, the aqueous solution When the viscosity of is increased by 10% or more compared to before adding the polysaccharide, it can be determined that the polysaccharide to be evaluated can increase the viscosity of the contacted body fluid. Viscosity measurement measures an aqueous solution (20 degreeC) using the Tokyo Keiki B-type viscometer (B8M type) before addition of polysaccharide and 30 seconds after addition of polysaccharide.

  The water-absorbing polymer conventionally used as a material for the absorbent core does not move in the absorbent core, and exhibits an absorption / immobilization effect only after the body fluid reaches the position where it exists. Has a passive absorption and immobilization mechanism. On the other hand, the polysaccharide used in the present invention has the effect of immobilizing the liquid by gelation as well as the water-absorbing polymer, and has the property of dissolving or dissociating and diffusing in water. Once contact with the polysaccharide occurs, the liquid at the contact portion is immobilized, and the polysaccharide dissolves or dissociates in the body fluid and diffuses away from the position where the polysaccharide is present. Body fluids in the different positions are also immobilized. That is, the polysaccharide used in the present invention has an active absorption / immobilization mechanism. Therefore, even if all the high-viscosity liquids such as loose stool cannot reach the position where the polysaccharide exists, the high-viscosity liquids can be immobilized. Moreover, in the present invention, the polysaccharide reacts with a polyvalent metal ion (for example, calcium ion or aluminum ion) contained in a small amount in the body fluid to form a complex, and the polysaccharide itself is thickened and excreted. Only when it comes into contact with a body fluid, the body fluid is thickened and the property of immobilizing it is utilized. Due to such properties of the polysaccharide, not only a low-viscosity liquid such as urine but also a leakage preventing effect for a high-viscosity liquid such as soft stool and blood is enhanced. In addition, unlike the water-absorbing polymer, the polysaccharide used in the present invention does not cause a problem of gel blocking, so it can be present in the absorbent article on the side relatively close to the wearer's skin (skin facing surface side). It becomes.

  In the present invention, a polysaccharide that can be thickened in the presence of a polyvalent metal ion is used as the polysaccharide contained in the absorbent core. In the present invention, it is necessary to immobilize the high-viscosity liquid by quickly dissolving or dissociating and diffusing the polysaccharide in the high-viscosity liquid by contact with a slight high-viscosity liquid (water). Therefore, it is preferable that the polysaccharide used in the present invention does not contain a polyvalent metal ion.

  Moreover, it is preferable that the absorbent article (especially absorbent core) of this invention does not contain a polyvalent metal ion in relation to using what does not contain a polyvalent metal ion as a polysaccharide. However, in reality, a trace amount of polyvalent metal ions may be inevitably mixed in the manufacturing process of the polysaccharide, the manufacturing process of the absorbent article, and the manufacturing process of each component of the absorbent article. Therefore, in the present invention, the polysaccharide or absorbent article does not contain polyvalent metal ions means not only a form containing no polyvalent metal ions or substances that generate polyvalent metal ions in water. In addition, a form in which a polyvalent metal ion up to an amount allowed to develop a thickening capable of exhibiting a leakage preventing effect or a substance that generates a polyvalent metal ion in water is inevitably mixed is included. .

  In the present specification, the polysaccharide containing no polyvalent metal ion means “polysaccharide which does not form a metal salt” and “polysaccharide which forms a salt with a monovalent metal ion”. Examples of polysaccharides that do not form metal salts include pectin, gellan gum, κ-carrageenan, glucomannan, guar gum, casein, propylene glycol alginate, and the like. These can be used alone or in combination of two or more. Can be used. Examples of polysaccharides that form salts with monovalent metal ions include sodium alginate. Among these polysaccharides, pectin, sodium alginate, gellan gum and κ-carrageenan are particularly preferably used in the present invention from the viewpoint of production cost and solubility in water.

  Further, as described above, the polysaccharide used in the present invention actively dissolves and diffuses in the excreted body fluid and thickens the body fluid, so that it is water-soluble or dissociates into water. To get. Here, dissociating into water means that it is not completely dissolved in water but is dispersible in water, and may be present in water in a state where the molecular chains of the polysaccharide are intertwined. means. Moreover, completely dissolving in water means that all the molecules of one polysaccharide are hydrated in water. Moreover, in order to make the property of the gel formed by thickening speed and viscosity of the polysaccharide appropriate, etc., the pH can be adjusted by adjusting the degree of esterification of the polysaccharide or coexisting with an organic acid or the like. You may adjust it.

  In the present invention, since polysaccharides are required to react and thicken sensitively to excreted body fluids, polysaccharides are present in the absorbent core in a state where they can be dissolved or dissociated in water. It is preferable to do. Examples of the state in which the polysaccharide can be dissolved or dissociated in water include, for example, a state where the polysaccharide powder is dispersed in the absorbent core, and the skin-facing surface or non-skin-facing surface of the absorbent core. The state that it is sprayed is mentioned.

  The polysaccharide may be used in a powder state, or may be used in the state of particles or in a water-soluble capsule. When the polysaccharide is used in the form of powder or particles, its size is preferably 10 μm or more, more preferably 50 μm or more, and preferably 1000 μm or less, more preferably 500 μm or less, more specifically, preferably It is 50-1000 micrometers, More preferably, it is 50-500 micrometers. When the polysaccharide is used in a state of being encapsulated in a capsule, the size of the capsule is preferably 300 μm or more, more preferably 500 μm or more, and preferably 2000 μm or less, more preferably 1000 μm or less, more specifically. Is preferably 300 to 2000 μm, more preferably 500 to 1000 μm.

In the present invention, the amount of polysaccharide used is preferably 10 g / m ² or more, more preferably 30 g / m ² or more, and preferably 200 g / m ² from the viewpoint of production cost and thickening ability (more effective in preventing leakage). ² or less, more preferably 100 g / m ² or less, and more specifically, preferably 10 to 200 g / m ^2, more preferably at 30 to 100 g / m ^2. Moreover, in the absorptive core which concerns on this invention, the content mass ratio (polysaccharide / fiber material) of fiber materials, such as a wood pulp contained in this, and polysaccharide (polysaccharide / fiber material) becomes like this. Preferably it is 10/1000 or more, More preferably, 1 / 5 or more, and preferably 200/50 or less, more preferably 1/1 or less. Further, the content of the pulp fiber in the absorbent core according to the present invention is preferably 50 g / m ² or more, preferably 1000 g / m ² or less, more preferably 300 g / m ² or less, and preferably 50 It is -1000 g / m < ² >, More preferably, it is 50-300 g / m < ² >.

In addition, it can be confirmed by the following method whether the polysaccharide is contained in the absorptive core. First, an absorptive core is taken out from the absorptive article, and this is cut into a scissors shape (length 2 cm, width 2 cm, height about 0.5 cm). Next, the absorptive cores cut in the shape of ridges are grouped into fiber materials (hydrophilic fibers) and water-absorbing polymer particles, and water is added to each group. This addition is for dissolving the polysaccharide. Next, what was hydrated to the fiber material and those hydrated to the water-absorbing polymer particles were filtered, and the solvent was distilled off to obtain a dried product. Then, for each of the dried product derived from the fiber material and the dried product derived from the water-absorbing polymer particles, an aqueous solution was prepared using heavy water as a solvent, and ¹ H-NMR and / or ¹³ C- was used using a nuclear magnetic resonance (NMR) apparatus. In addition to performing structural analysis by NMR, the viscosity is measured according to the method for evaluating viscosity increase, and the presence or absence of polysaccharides is determined from the results.

  In determining whether or not a polysaccharide is contained in the absorbent core, the reason why the viscosity measurement according to the thickening evaluation method and the structural analysis by NMR are used in combination is as follows. As a result of measuring the viscosity of the aqueous solution of the dried product according to the above-described method for evaluating thickening, even if thickening is recognized, the thickening is caused by polysaccharides or other factors (for example, water absorption) It is unclear whether this is due to the inclusion of fine powder of the conductive polymer). On the other hand, if the dried product is obtained by separation until it becomes a single substance, it can be determined from the NMR spectrum whether the polysaccharide is a polysaccharide having a thickening action. However, in NMR alone, when the dried solid is not isolated until it becomes a single substance, but is in a mixture (for example, a water-absorbing polymer or oil is mixed), the dried solid Even if it is found that the polysaccharide is contained therein, it may not always be determined that the polysaccharide can “thicken the contacted body fluid”. Therefore, the viscosity measurement according to the thickening evaluation method and the structural analysis by NMR are used together with the combined viscosity measurement.

  As mentioned above, although embodiment of this invention was described, this invention is not restrict | limited to the said embodiment, It can change suitably. For example, in the embodiment, the number of the groove portions of the absorbent core is two, but the number of the groove portions may be one, or may be three or more. When the number of the groove portions is one or three or more, the absorbent core is symmetric with respect to the longitudinal center line that bisects the absorbent core in the horizontal direction as in the above-described embodiment where the groove portions are two. Preferably it is. Moreover, the groove part of an absorptive core is not restrict | limited to linear shape (rectangular shape) like the groove part 4 in the said embodiment, It may be curved or bent, and should just extend the vertical direction as the whole groove part. In addition, the absorbent article of the present invention is not limited to pants-type disposable diapers, but broadly includes articles used for absorbing liquid discharged from the human body, including unfoldable disposable diapers, sanitary napkins, sanitary shorts, etc. Is included. The following additional notes are disclosed with respect to the embodiment of the present invention described above.

<1>
With an absorbent core that absorbs and holds excreted bodily fluid, and has an abdominal side portion disposed on the abdomen side of the wearer, a back side portion disposed on the back side, and a crotch portion positioned therebetween, An absorbent article having a longitudinal direction extending from the abdominal side portion to the back side portion through the crotch portion and a lateral direction perpendicular thereto,
The absorbent core has an opening in the skin-facing surface of the absorbent core and has a longitudinally extending groove, and thickens body fluid in at least a part of the absorbent core adjacent to the groove and in the thickness direction. A polysaccharide-containing region containing a polysaccharide that can be made, and a polysaccharide-free region in which the polysaccharide is not contained throughout the thickness direction of the absorbent core,
In the crotch part, out of all the grooves of the absorbent core, the laterally outermost groove part that is farthest from the longitudinal center line that bisects the absorbent core in the lateral direction, An absorbent article in which the polysaccharide-containing region is arranged adjacent to the laterally outermost groove.

<2>
The absorbent article according to <1>, wherein the groove is a through-hole penetrating the absorbent core in a thickness direction.
<3>
The absorbent article according to <1> or <2>, wherein the absorbent core includes a fiber assembly.
<4>
The absorbent article according to any one of <1> to <3>, wherein the absorbent core includes a fiber aggregate in which a particulate water-absorbing polymer is held.
<5>
The groove portion is disposed at least in the crotch portion, and in a longitudinal central portion (vertical central portion of the crotch portion) when the absorbent core is divided into three equal parts in the longitudinal direction, The absorbent article as described in any one of said <1>-<4> extended over the full length of a direction.

<6>
The absorbent article according to any one of <1> to <5>, wherein the polysaccharide is a polysaccharide that can thicken in the presence of a polyvalent metal ion.
<7>
The absorbent article according to <6>, wherein the polysaccharide does not contain a polyvalent metal ion.
<8>
The polysaccharide not containing a polyvalent metal ion is one or more metal salts selected from the group consisting of pectin, gellan gum, κ-carrageenan, glucomannan, guar gum, casein and propylene glycol alginate. The absorbent article according to <7>, wherein the absorbent article is an unformed polysaccharide.
<9>
The absorbent article according to any one of <1> to <8>, wherein the polysaccharide is sodium alginate.
<10>
<1> to <9, wherein the polysaccharide is dispersed in the absorbent core in a powder state, or is dispersed on the skin facing surface or the non-skin facing surface of the absorbent core in a powder state. > The absorbent article as described in any one of>.

<11>
In the polysaccharide-containing region located in the laterally outer side of the laterally outermost groove portion and adjacent thereto, the polysaccharide is contained in the entire region in the thickness direction of the absorbent core. The absorbent article according to any one of> to <10>.
<12>
The polysaccharide-free region is adjacent to the polysaccharide-containing region on the laterally outward side of the polysaccharide-containing region that is positioned laterally outward of the laterally outermost groove and adjacent thereto. The absorbent article according to any one of <1> to <11>, which is arranged.
<13>
The absorbent article according to any one of <1> to <12>, wherein the absorbent core has two slit-like groove portions that are linear (rectangular) in plan view.
<14>
Two said groove parts are absorbent articles of the said <13> description which is divided | segmented and distribute | arranged to one side and the other side on the basis of the longitudinal centerline which bisects the said absorbent core in a horizontal direction.

<15>
The absorbent core has a groove gap portion sandwiched between the two groove portions at the lateral center of the crotch part, and the polysaccharide-containing region is disposed adjacent to the groove gap portion. In the polysaccharide-containing region in the groove gap, the polysaccharide is unevenly distributed on the non-skin facing surface side of the absorbent core, according to any one of <1> to <14>. Absorbent article.
<16>
In the polysaccharide-containing region of the groove gap, the thickness of the polysaccharide existing part unevenly distributed on the non-skin facing surface side is preferably 1% or more with respect to the thickness of the polysaccharide-containing region (groove gap). The absorbent article according to <15>, more preferably 5% or more, and preferably 70% or less, more preferably 50% or less.
<17>
<15> or <16> wherein the width of the gap between the grooves (the interval between the two grooves) is preferably 60 mm or more, more preferably 70 mm or more, and preferably 100 mm or less, more preferably 90 mm or less. The absorbent article as described.

<18>
The said groove part is an absorbent article as described in any one of said <1>-<17> which is not open | released at the longitudinal direction edge part of the said absorbent core, but has a closed end part.
<19>
The polysaccharide-containing region and the polysaccharide-free region are arranged in this order from the inside in the longitudinal direction to the outside in the longitudinal direction outward of the closed end of the groove, and both regions are adjacent to each other. The absorbent article according to <18>.
<20>
The absorbent article according to any one of <1> to <19>, wherein the entire peripheral edge of the absorbent core is formed from the polysaccharide-free region.
<21>
<19> or <20> description in which the polysaccharide is contained in the whole area of the thickness direction of the absorptive core in the polysaccharide content field located in the lengthwise direction outside rather than the closed end of the groove part. Absorbent article.

<22>
The width of the groove (the length in the direction orthogonal to the length direction of the groove) is preferably 3 mm or more, more preferably 5 mm or more, and preferably 20 mm or less, more preferably 15 mm or less. The absorbent article as described in any one of <21>.
<23>
The longitudinal total length of the groove part is preferably 60% or more, more preferably 70% or more, and preferably 95% or less, more preferably 90% or less with respect to the longitudinal total length of the absorbent core. The absorbent article as described in any one of <1>-<22>.
<24>
The width of the polysaccharide-containing region that is adjacent to the groove portion in the lateral direction (the polysaccharide-containing region that is positioned laterally outward of the lateral outermost groove portion and is adjacent thereto) is preferably 5 mm. The absorbent article according to any one of <1> to <23>, more preferably 7.5 mm or more, and preferably 20 mm or less, and more preferably 15 mm or less.
<25>
<1> The width of the polysaccharide-containing region adjacent to the groove in the longitudinal direction is preferably 5 mm or more, more preferably 7.5 mm or more, and preferably 20 mm or less, more preferably 15 mm or less. The absorbent article as described in any one of-<24>.

<26>
When the polysaccharide is used in the form of powder or particles, the size is preferably 10 μm or more, more preferably 50 μm or more, and preferably 1000 μm or less, more preferably 500 μm or less. The absorbent article as described in any one of 25>.
<27>
When the polysaccharide is used in a state of being encapsulated in a capsule, the size of the capsule is preferably 300 μm or more, more preferably 500 μm or more, and preferably 2000 μm or less, more preferably 1000 μm or less <1 The absorbent article according to any one of> to <25>.
<28>
The content of the polysaccharide in the absorbent core is preferably 10 g / m ² or more, more preferably 30 g / m ² or more, and preferably 200 g / m ² or less, more preferably 100 g / m ² or less. The absorbent article as described in any one of said <1>-<27>.
<29>
In the absorbent core, the mass ratio of the fiber material and the polysaccharide contained therein (polysaccharide / fiber material) is preferably 10/1000 or more, more preferably 1/5 or more, and preferably The absorbent article according to any one of <1> to <28>, which is 200/50 or less, more preferably 1/1 or less.

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

  In the following Examples 1 to 4, as the absorbent core, a plan view is shown in FIG. 6, and a cross-sectional view (a cross-sectional view taken along the line II-II in FIG. 6) is shown in FIG. 5, FIG. The absorptive core which is a form or its modification was used. In addition, although the part which attached | subjected the diagonal line in FIGS. 6-8 has shown the containing part of a polysaccharide, in FIG. 6, the distribution state (whether it is unevenly distributed in the non-skin opposing surface side) of the thickness direction of a polysaccharide Etc.), the polysaccharide-containing region is hatched.

  As shown in FIG. 6, the absorbent core having the form shown in FIG. 6 in plan view has a groove gap portion (central absorption portion) 26 located at the center in the lateral direction Y of the absorbent core, and the groove gap portion 26. A pair of side absorbent parts 27, 27 located on both outer sides in the lateral direction Y, and the absorbent core between the groove part gap part 26 and the pair of side absorbent parts 27, 27, respectively. Is provided in the thickness direction. In the absorbent core having the form shown in FIG. 6 in plan view, both groove portions 4 and 4 are open to the longitudinal end portions 23E and 23E of the absorbent core, and the longitudinal direction (longitudinal direction) is the front and rear. The end portion does not have a closed end portion, and the groove portion gap portion 26 and the side absorption portion 27 are completely divided by the groove portion 4.

The absorptive core having the form shown in FIG. 6 in plan view was produced as follows. According to a conventional method using a fiber stacking device, wood pulp (NB416L1000W manufactured by Weyerhaeuser Company Limited), which is a hydrophilic fiber, was first deposited on the fiber drum of the device, and then a water-absorbing polymer (sun diamond polymer) was deposited on the deposit. A piled body was obtained by depositing IM113) and hydrophilic fibers. In the obtained fiber stack, the basis weight of the hydrophilic fiber was 135 g / m ² , the basis weight of the water absorbent polymer was 126 g / m ² , and the thickness was 2.5 mm. A rectangular parallelepiped having a longitudinal length of 200 mm, a lateral length of 50 mm, and a thickness of 2.5 mm is cut out from the piled body to form a groove portion (central absorption portion) 26, and the longitudinal length is 200 mm and the lateral length. Two rectangular parallelepipeds having a thickness of 40 mm and a thickness of 2.5 mm are cut out to form side absorbers 27, which are arranged so that the longitudinal length of the groove 4 is 200 mm and the lateral length (width) is 10 mm. An absorbent core was obtained.

Sodium alginate (manufactured by Wako Pure Chemical Industries, Ltd.) was used as a polysaccharide to be contained in the absorbent core having the form shown in FIG. 6 in plan view. In the case where the polysaccharide is contained only in a part in the thickness direction of the absorbent core (is unevenly distributed on the skin facing surface side or the non-skin facing surface side), in the groove portion gap portion (central absorbing portion) 26 or the side portion absorbing portion 27, Sodium alginate was sprayed at a basis weight of 20 g / m ² on a predetermined portion in the thickness direction of the band in the plan view extending 10 mm laterally inward from the side edge adjacent to the groove 4. In addition, when the polysaccharide is contained throughout the thickness direction of the absorbent core, sodium alginate was used as a material for forming the water-absorbent core in the absorbent core molding stage. That is, a hydrophilic fiber was first deposited on the pile drum, and then a water absorbent polymer, the hydrophilic fiber and sodium alginate were deposited on the pile to obtain a pile. In the obtained fiber stack, the basis weight of the hydrophilic fiber was 135 g / m ² , the basis weight of the water-absorbing polymer was 126 g / m ² , and the basis weight of sodium alginate was 50 g / m ² . In addition, this sodium alginate has a viscosity of 16 mm ² / S before addition of the sodium alginate and a viscosity of 96 mm ² / S after the addition in the viscosity measurement according to the method for evaluating viscosity increase. Since the viscosity increased by 10 percent or more compared to the viscosity before addition, it can be determined that the polysaccharide can increase the viscosity of the contacted body fluid.

[Example 1]
According to a conventional method, a pants-type disposable diaper having the same basic configuration as the diaper 1 shown in FIGS. SC250R with a basis weight of 25 g / m ² (Rengo Non-Woven Products Co., Ltd.) is used as the top sheet, and C3Y6020A5A (with Mitsubishi Plastics Co., Ltd.) with a basis weight of 20 g / m ² is used as the exterior body. The exterior body of a commercially available pants-type disposable diaper (trade name “Relief is a pants-type relief” made by Kao Corporation) was used. As the absorbent core, an absorbent core having a groove portion 4 made of a through-hole having a form shown in FIG. 6 in a plan view and a cross-sectional view (taken along line II-II in FIG. 6) in FIG. 7 is used. The absorbent core was coated with a core wrap sheet made of hydrophilic and liquid-permeable paper having a basis weight of 16 g / m ² to prepare an absorbent body, and the absorbent body was incorporated into a diaper. In the absorbent core used in Example 1, as shown in FIG. 7, the polysaccharide (polysaccharide existing part 50) is unevenly distributed on the skin facing surface side of the absorbent core.

[Example 2]
As the absorbent core, except that an absorbent core having a groove portion 4 made of a through-hole having a form shown in FIG. 6 in a plan view and a cross-sectional view (taken along line II-II in FIG. 6) in FIG. 5 is used. A pants-type disposable diaper was produced in the same manner as in Example 1.

Example 3
As the absorbent core, except that an absorbent core having a groove portion 4 made of a through-hole having a form shown in FIG. 6 in a plan view and a cross-sectional view (taken along line II-II in FIG. 6) in FIG. 8 is used. A pants-type disposable diaper was produced in the same manner as in Example 1. In the absorbent core used in Example 3, as shown in FIG. 8, the polysaccharide (polysaccharide existing part 50) is unevenly distributed on the non-skin facing surface side of the absorbent core.

Example 4
As an absorptive core, except that the polysaccharide is uniformly contained in the whole of the pair of side absorbent bodies 27, 27 (the polysaccharide non-containing region 6 is not arranged on the side absorbent body 27), The same absorptive core used in Example 2 was used. Except for the above, a pants-type disposable diaper was produced in the same manner as in Example 1.

[Comparative Example 1]
As an absorptive core, the absorptive core which does not have a groove part and does not contain a polysaccharide was used. The absorbent core used in Comparative Example 1 is a flat plate-like product having a longitudinal length of 200 mm, a lateral length of 150 mm, and a thickness of 2.5 mm, and has a composition other than the point that no polysaccharide is contained. The same as the absorbent core used in each example. Except for the above, a pants-type disposable diaper was produced in the same manner as in Example 1.

[Comparative Example 2]
A pants-type disposable diaper was produced in the same manner as in Example 1 except that the polysaccharide was not contained in the absorbent core.

[Comparative Example 3]
A pants-type disposable diaper was produced in the same manner as in Comparative Example 1 except that a polysaccharide (sodium alginate) was incorporated in the entire area of the absorbent core facing the skin. The basis weight of sodium alginate in the absorbent core used in Comparative Example 3 was 20 g / m ² .

[Evaluation]
About the diaper of each Example and a comparative example, the liquid diffusion length of the vertical direction and each horizontal direction was measured with the following method. The results are shown in Table 1 below.

<Measurement method of liquid diffusion length>
The disposable diaper to be measured is spread in a flat shape, the top sheet is faced up, and fixed on a smooth sloping surface with a slant angle of 30 ° with respect to the horizontal plane in a non-pressurized state. The center of the absorbent core in the top sheet 10 g of artificial urine was injected into the portion corresponding to the position at an injection speed of 2 g / second and absorbed. After 10 minutes from the injection of the artificial urine, the absorbent core is taken out from the disposable diaper, and using a ruler, the maximum length in the vertical direction and the horizontal direction from the injection position in the absorption holding part of the artificial urine is measured. The measured values were the longitudinal diffusion length and the lateral diffusion length. The diffusion length can be measured by adding a pigment such as red or blue to the artificial urine so that the range in which the artificial urine diffuses in the absorbent core is visible. Regarding the longitudinal liquid diffusion length, it is judged that the longer the numerical value is, the more the liquid diffusion in the vertical direction is promoted, and the evaluation becomes high. Regarding the lateral liquid diffusion length, it is judged that the smaller the numerical value, the more the liquid diffusion in the lateral direction is suppressed, and the higher the evaluation is. Therefore, the larger the ratio of the vertical liquid diffusion length to the horizontal liquid diffusion length (longitudinal liquid diffusion length / lateral liquid diffusion length), the higher the evaluation. The composition of artificial urine is as follows. 1.9% by weight of urea, 0.8% by weight of sodium chloride, 0.1% by weight of magnesium sulfate (septahydrate), 0.1% by weight of calcium chloride (dihydrate), 0.1% by weight of potassium sulfate , 0.1% by mass of polyoxyethylene lauryl ether, 0.1% of red No. 2 and ion-exchanged water (remaining amount).

  The influence of the groove and the polysaccharide on the control of the liquid diffusibility in the absorbent core is suggested from the comparison between Examples 1 to 4 and Comparative Examples 1 to 3. As shown in Table 1, Examples 1-4 which used the absorptive core which has a groove part and contains polysaccharide are longitudinal direction liquid diffusion length compared with Comparative Examples 1-3 in which both elements are not arranged. Is long and the lateral fluid diffusion length is short, resulting in a ratio of both lengths of 1.1 or more, promoting the diffusion of body fluids in the longitudinal direction and suppressing the diffusion of body fluids in the lateral direction. It turns out that it is what you get.

  In addition, as shown in FIG. 4, in order to confirm the effectiveness that the groove part of an absorptive core does not open | release at the longitudinal direction edge part but has a closed end part, it mentioned above as an absorptive core. A pants-type disposable diaper was produced in the same manner as in Example 1 except that the same absorbent core 23 (see FIGS. 4 and 5) was used. In this absorbent core, the width W2 and the width W3 (see FIG. 4) of the polysaccharide-containing region are each 10 mm, and the distance between the closed end 4E of the groove 4 and the longitudinal end 23E of the absorbent core 23 is 55 mm. It was. About this diaper, when the liquid diffusion length in the vertical direction and the horizontal direction was measured by the above method, the liquid diffusion length in the vertical direction was 93 mm and the liquid diffusion length in the horizontal direction was 87 mm. The ratio of the longitudinal liquid diffusion length was greater than 1. From the above results, it can be understood that the liquid diffusibility was appropriately controlled in the diaper in which the groove portion in the absorbent core has a closed end as in the diapers of other examples.

1 Pants-type disposable diaper (absorbent article)
2 Absorbent body 21 Top sheet 22 Back sheet 23 Absorbent core 23a Absorbent core skin facing surface 23b Absorbent core non-skin facing surface 26 Groove gap 3 Exterior body 31 Outer sheet 32 Inner sheet 4 Groove Outward groove)
4E Closed end 5 of groove 5 Polysaccharide-containing region 50 Polysaccharide existing portion 51 Lateral outermost polysaccharide-containing region 6 Non-polysaccharide-containing region A Ventral side B Crotch C Back side X Longitudinal direction Y Lateral direction

Claims (6)

With an absorbent core that absorbs and holds excreted bodily fluid, and has an abdominal side portion disposed on the abdomen side of the wearer, a back side portion disposed on the back side, and a crotch portion positioned therebetween, An absorbent article having a longitudinal direction extending from the abdominal side portion to the back side portion through the crotch portion and a lateral direction perpendicular thereto,
The absorbent core has an opening in the skin-facing surface of the absorbent core and has a longitudinally extending groove, and thickens body fluid in at least a part of the absorbent core adjacent to the groove and in the thickness direction. A polysaccharide-containing region containing a polysaccharide that can be made, and a polysaccharide-free region in which the polysaccharide is not contained throughout the thickness direction of the absorbent core,
In the crotch part, out of all the grooves of the absorbent core, the laterally outermost groove part that is farthest from the longitudinal center line that bisects the absorbent core in the lateral direction, An absorbent article in which the polysaccharide-containing region is arranged adjacent to the laterally outermost groove.   The polysaccharide is contained in the entire region in the thickness direction of the absorbent core in the polysaccharide-containing region located in the laterally outer side of the laterally outermost groove and adjacent thereto. The absorbent article as described.   The polysaccharide-free region is adjacent to the polysaccharide-containing region on the laterally outward side of the polysaccharide-containing region that is positioned laterally outward of the laterally outermost groove and adjacent thereto. The absorptive article according to claim 1 or 2 arranged.   The absorbent core has a groove gap portion sandwiched between the two groove portions at the lateral center of the crotch part, and the polysaccharide-containing region is disposed adjacent to the groove gap portion. The absorbent article according to any one of claims 1 to 3, wherein the polysaccharide is unevenly distributed on the non-skin facing surface side of the absorbent core in the polysaccharide-containing region in the gap portion of the groove. .   The said groove part is an absorbent article as described in any one of Claims 1-4 which has the closed end part, without being open | released by the longitudinal direction edge part of the said absorbent core.   The polysaccharide-containing region and the polysaccharide-free region are arranged in this order from the inside in the longitudinal direction to the outside in the longitudinal direction outward of the closed end of the groove, and both regions are adjacent to each other. The absorbent article according to claim 5.

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