JP2019208848A - Absorbent article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an absorbent article that can be used without worrying about odor even when the excretion amount of body fluid is relatively large or when it is used for a long time. SOLUTION: The absorber 4 has a laminated structure including a front-side absorbent sheet 41, a back-side absorbent sheet 42, and a central absorbent portion 43 located between the both sheets 41 and 42. The central absorbent portion 43 has a laminated structure in which the central absorbent sheet 402 is laminated in a plurality of layers. The sheet 402 has, in its thickness direction, a first region E and a second region F in which an antibacterial agent is arranged and the content of the superabsorbent polymer is higher than that of the first region E, and the sheets 41, 42. Higher content of superabsorbent polymer than. Inside the laminated structure of the sheet 402, the second region F is formed with a second region facing portion 2F in which the second regions F face each other without the first region E interposed therebetween. [Selection diagram] Figure 2

Description

  The present invention relates to an absorbent article.

  In an absorbent article such as a sanitary napkin, after absorbing bodily fluids such as menstrual blood, unpleasant odors may be generated, or troubles such as itchiness may occur due to contact between the wearer's skin and bodily fluids. For the purpose of eliminating such inconveniences, various studies have been conducted on the antibacterial function of absorbent articles. For example, in Patent Document 1, a functional absorber including a functional material that provides at least an additional function such as an antibacterial function is provided on the wearer side of the functional absorber, in the central portion of the absorbent article, An absorbent article is described that includes a wearer-side absorber that is less diffusible for bodily fluids than the functional absorber. Patent Document 2 describes an absorbent article including an antibacterial active sheet containing an antibacterial agent in which a low-density part having a fiber amount of less than 50% by mass is formed compared to the surroundings. Further, in Patent Document 3, as the absorbent body in the absorbent article, the mass ratio of the superabsorbent polymer relative to the total amount of the mass of the low moisture retention fiber such as synthetic fiber and the mass of the superabsorbent polymer is relatively It has a high polymer-rich region and a fiber-rich region having a relatively low mass ratio, and an antibacterial agent is contained in the polymer-rich region. [0066] of Patent Document 3 describes a form of a composition containing a fragrance as one form of a hemagglutinating agent disposed in the absorber.

JP 2010-110443 A JP 2014-158509 A JP 2017-217071 A

  If a bad odor is generated from the absorbent article during use of the absorbent article, it will make the user feel embarrassed. Therefore, it is necessary to take measures against the bad odor in the absorbent article. As one of the main causes of malodor from the absorbent article, the propagation of bacteria in the absorbent article can be considered. In particular, when the amount of excretion of body fluid such as menstrual blood is relatively large, or when the absorbent article is worn for a relatively long time, the propagation of bacteria tends to be promoted and bad odor tends to occur. The absorbent articles described in Patent Documents 1 to 3 are provided with a certain antibacterial function, and countermeasures against malodors are taken. There is room.

  An object of the present invention is to provide an absorbent article that can eliminate the drawbacks of the above-described prior art, specifically, when the amount of excretion of body fluid is relatively large or when it is used for a long time. Moreover, it is related with providing the absorbent article which can be used without minding an odor.

  The present invention includes a liquid-permeable surface sheet that forms a skin-facing surface, a back sheet that forms a non-skin-facing surface, and an absorbent sheet that is positioned between both the sheets and includes a fiber material. An absorbent article having a longitudinal direction corresponding to the front-rear direction of the wearer and a lateral direction perpendicular thereto, wherein the absorbent body is at least in the lateral direction of the absorbent body, It has a laminated structure including a front-side absorbent sheet located on the skin facing surface side, a back-side absorbent sheet located on the non-skin facing surface side, and a central absorbent portion located between both sheets, the center The absorbent part has a laminated structure in which a central absorbent sheet is laminated in a plurality of layers, and the central absorbent part is more per unit area of the superabsorbent polymer than the front side absorbent sheet and the back side absorbent sheet. The central absorbent sheet has a high content of In the thickness direction, the first region and the second region in which the antibacterial agent is disposed and the content of the superabsorbent polymer is larger than that of the first region, and inside the laminated structure of the central absorbent sheet The absorbent article has a second region facing portion in which the second regions face each other without the first region interposed therebetween.

  ADVANTAGE OF THE INVENTION According to this invention, even when it is the case where the amount of excretion of a bodily fluid is comparatively large, or the case of long-time use, the absorbent article which can be used without minding an odor is provided.

FIG. 1 is a plan view showing the skin facing surface side (surface sheet side) of a sanitary napkin which is a preferred embodiment of the absorbent article of the present invention. FIG. 2 is a cross-sectional view schematically showing a cross section taken along line II of FIG. FIG. 3 is a plan view showing the skin facing surface side of the absorbent body included in the sanitary napkin shown in FIG. 1. 4A is a cross-sectional view schematically showing a cross section along the horizontal direction of the central absorbent portion constituting the absorbent body included in the sanitary napkin shown in FIG. 1, and FIG. 4B is the central absorbent portion. FIG. 6 is a cross-sectional view of the second region facing portion (a portion where the second regions face each other without passing through the first region) in black. FIG. 5 is an enlarged cross-sectional view schematically showing a cross-sectional structure in the thickness direction of the central absorbent sheet constituting the central absorbent portion shown in FIG. 6 (a) to 6 (c) are cross-sectional views schematically showing cross sections along the horizontal direction of other embodiments of the central absorbent portion according to the present invention (corresponding to FIG. 4 (a)). It is.

  Hereinafter, the absorbent article of the present invention will be described based on its preferred embodiments with reference to the drawings. The sanitary napkin 1 which is one Embodiment of the absorbent article of this invention is shown by FIG.1 and FIG.2. As shown in FIGS. 1 and 2, the napkin 1 is positioned between a liquid-permeable top sheet 2 that forms a skin facing surface, a back sheet 3 that forms a non-skin facing surface, and both the sheets 2 and 3. The liquid-retaining absorbent 4 is provided.

  In the present specification, the “skin-facing surface” is a surface of the absorbent article or a component thereof (for example, the absorbent body 4) that is directed toward the wearer's skin when the absorbent article is worn, that is, relative to the wearer's skin. The side close to the skin, and the “non-skin facing surface” is directed to the side opposite to the skin side when the absorbent article is worn, that is, the side that is relatively far from the wearer's skin. It is the surface that is. In addition, "at the time of wearing" here means the state in which the normal proper wearing position, that is, the correct wearing position of the absorbent article is maintained.

  As shown in FIG. 1, the napkin 1 has a longitudinal direction X corresponding to the wearer's front-rear direction, extending from the wearer's abdomen side to the back side via the crotch portion, and a transverse direction Y orthogonal thereto. In addition, in the longitudinal direction X, an excretion part facing part B including an excretion spot part (not shown) facing the excretion part such as the vaginal opening of the wearer, and the abdomen side of the wearer from the excretion part facing part B It is divided into three parts: a front part A arranged on the (front side) and a rear part C arranged on the back side (rear side) of the wearer rather than the excretory part facing part B. In the following description, unless otherwise specified, the longitudinal direction X is the direction along the longitudinal direction X of the absorbent article or the longitudinal direction X of the absorbent article in its constituent members, and the lateral direction Y is the transverse direction of the absorbent article. It is the direction along the transverse direction Y of the absorbent article in the direction Y or its constituent members. The constituent member of the absorbent article includes a part of the absorbent article including a plurality of constituent members such as an absorbent main body and a central absorbent portion described later.

  As shown in FIG. 1, the napkin 1 has an absorptive main body 5 that is long in the vertical direction X, and outwards in the lateral direction Y from both side portions along the vertical direction X of the excretory part-facing portion B of the absorbent main body 5. And a pair of wing portions 7, 7 extending in the direction. The absorptive main body 5 is a main part of the napkin 1 and includes the top sheet 2, the back sheet 3 and the absorber 4, and in the longitudinal direction X, the front part A, the excretory part facing part B, and the rear part C. It is divided into three.

  In addition, the excretion part opposing part in the absorbent article of this invention is the longitudinal direction (longitudinal direction, in the figure) of this absorbent article, when the absorbent article has a wing part like the napkin 1 shown in FIG. For example, the napkin 1 is sandwiched between the root along the vertical direction X of one wing portion 7 and the root along the vertical direction X of the other wing portion 7. This area Moreover, although not shown in figure, the excretion part opposing part in the absorbent article which does not have a wing part is an area | region of the center of the vertical direction when this absorbent article is equally divided into 3 area | regions in the vertical direction. is there.

  As shown in FIGS. 1 and 2, the top sheet 2 covers the entire skin facing surface of the absorbent body 4. On the other hand, the back sheet 3 covers the entire area of the non-skin facing surface of the absorbent body 4 and further extends outward in the lateral direction Y from both side edges along the longitudinal direction X of the absorbent body 4 to be described later. 6, a side flap portion (a portion made of a member extending outwardly in the lateral direction Y from the absorber 4) is formed. The back sheet 3 and the side leak-proof sheet 6 are joined to each other by known joining means such as an adhesive, a heat seal, and an ultrasonic seal at the extended portions from both side edges along the longitudinal direction X of the absorber 4. Yes. In the napkin 1, the absorbent body 4 is thus sandwiched between the top sheet 2 and the back sheet 3, and the top sheet 2 or the side leak-proof sheet 6 and the back sheet 3 are joined around the entire outer edge of the napkin 1. Yes. For joining between the sheets constituting the napkin 1, any joining means such as an adhesive, heat sealing, ultrasonic sealing or the like is used.

  As shown in FIG. 1, the side flap portions project greatly outward in the lateral direction Y at the excretory portion facing portion B, and thereby a pair of side flap portions are provided on both the left and right sides along the longitudinal direction X of the absorbent main body 5. The wing portions 7, 7 are extended. The wing portion 7 has a substantially trapezoidal shape in which the lower base (side longer than the upper base) is located on the side of the absorbent main body 5 in a plan view as shown in FIG. Is provided with a wing portion adhesive portion (not shown) for fixing the wing portion 7 to clothes such as shorts. The wing portion 7 is used by being folded back to the non-skin facing surface (outer surface) side of the crotch portion of clothes such as shorts. Moreover, the main body adhesion part (not shown) used for fixation to the crotch part of clothes, such as shorts, is provided in the non-skin opposing surface of the absorptive main body 5. FIG. Each of the wing part adhesive part and the main body adhesive part is covered with a release sheet (not shown) made of a film, a nonwoven fabric, paper, or the like before use.

  A pair of sides on both sides along the longitudinal direction X of the skin-facing surface of the absorbent body 5, that is, the skin-facing surface of the topsheet 2, overlaps with the left and right sides along the longitudinal direction X of the absorbent body 4 in plan view. Leakproof sheets 6 and 6 are disposed over substantially the entire length in the longitudinal direction X of the absorbent main body 5. The pair of side leak-proof sheets 6 and 6 are joined to other members such as the surface sheet 2 by means of known joining means such as an adhesive at joining lines extending in the longitudinal direction X. In the example shown in FIG. 1, the pair of side leak-proof sheets 6 and 6 are respectively a curved line-shaped first joining line 61 located in the excretory part facing part B and the longitudinal direction X of the first joining line 61. It is joined to the topsheet 2 with the zigzag-like second joining line 62 located at, but the present invention is not limited to this, for example, a linear joining line continuous over the entire length of the absorbent body 4, The side leak-proof sheet 6 and the surface sheet 2 may be joined. As shown in FIG. 2, the side leak-proof sheet 6 has a free end 6 a that is not joined to the top sheet 2 and a fixed end 6 b that is an inner end portion of the joining line 61 joined to the top sheet 2. When the napkin 1 is used, the fixed end 6b and the free end 6a are separated from the surface sheet 2 to form a leakproof pocket P that prevents side leakage to the side.

  In the napkin 1, as shown in FIG. 2, a second sheet 21 made of a nonwoven fabric is disposed between the top sheet 2 and the absorbent body 4. The second sheet 21 is a sheet called a sub-layer sheet in the technical field that is separate from the top sheet 2 and the absorber 4, and the top sheet 2 and / or the absorber 4 is provided in a stripe shape or a spiral shape. It is partially joined by an adhesive or the like. The second sheet 21 is a sheet that plays a role of improving the liquid permeability from the top sheet 2 to the absorber 4 or reducing the return of the liquid absorbed by the absorber 4 to the top sheet 2. . In addition, the absorbent article of this invention may not comprise a second sheet.

  As the top sheet 2, the back sheet 3, and the side leak-proof sheet 6, various kinds of materials conventionally used for absorbent articles such as sanitary napkins can be used without particular limitation. For example, as the surface sheet 2, a single layer or multilayer nonwoven fabric, an apertured film, or the like can be used. The surface sheet 2 may have unevenness on the skin facing surface side, or may have an oil agent or the like for controlling hydrophilicity attached to the surface of the constituent fibers. When the topsheet 2 has a multilayer structure, the topsheet 2 includes a first fiber layer located on the side close to the wearer's skin and a second fiber layer located on the side far from the wearer's skin. And both fiber layers are integrated in the thickness direction by a number of joints formed in part, and a portion of the first fiber layer located between the joints is convex. It is possible to use a concavo-convex sheet that protrudes and forms the concavo-convex convex portion. As the concavo-convex sheet in which the convex portion has a solid structure, for example, those described in Japanese Patent Application Laid-Open No. 2007-182626 and Japanese Patent Application Laid-Open No. 2002-187228 can be used. As the back sheet 3, a resin film, a laminate of a resin film and a nonwoven fabric, or the like can be used. The back sheet 3 is liquid-impermeable (including liquid-impermeable) or water-repellent, and it is also preferable to use a moisture-permeable resin film or the like. As the side leak-proof sheet 6, a laminated nonwoven fabric having a high water pressure resistance, a laminate of a resin film and a nonwoven fabric, or the like can be used.

  The absorber 4 is comprised including the absorbent sheets 401 and 402 containing a fiber material, as shown in FIGS. More specifically, the absorbent body 4 is located on the skin facing surface side (forms the skin facing surface of the absorbent body 4) at least in the central portion of the absorbent body 4 in the lateral direction Y. And a back side absorbent sheet 42 positioned on the non-skin facing surface side (forming the non-skin facing surface of the absorbent body 4), and a central absorbent portion 43 positioned between these sheets 41, 42. The sheets 41 and 42 are composed of a main body absorbent sheet 401, and the central absorbent portion 43 is composed of a central absorbent sheet 402. In the present embodiment, the laminated structure is located in the excretory part facing part B.

  In this specification, an absorptive sheet is an absorptive object fabricated in the shape of a sheet, and generally distinguishes it from an absorptive structure absorptive thing which piles absorptive material. Representative examples of the absorbent sheet include those described in Japanese Patent No. 2963647 and those described in Japanese Patent No. 2955223. As the absorbent sheet, the adhesive force generated in the wet superabsorbent polymer or a binder such as an adhesive or adhesive fiber added separately, between the constituent fibers or between the superabsorbent polymer and the constituent fibers. Those formed into a sheet form by bonding can be preferably used. Moreover, as an absorbent sheet, after depositing the absorbent sheet containing the pulp manufactured by the method of Unexamined-Japanese-Patent No. 8-246395, the pulverized pulp supplied on the airflow, and superabsorbent polymer, it adhere | attaches Absorbency obtained by spraying a superabsorbent polymer after applying a hot melt adhesive between a dry sheet hardened with an adhesive (for example, vinyl acetate adhesive, PVA, etc.), paper or nonwoven fabric containing pulp An absorptive sheet obtained by blending a superabsorbent polymer during the sheet, spunbond or melt blown nonwoven fabric manufacturing process can be used. These absorptive sheets can be cut into a predetermined shape and used as the above-mentioned sheet-shaped absorber.

  In the napkin 1, the central absorbent portion 43 (central absorbent sheet 402) is disposed only in the central portion of the absorbent body 4 in the lateral direction Y, as shown in FIGS. Although not arranged over the entire length (full width) in the lateral direction Y of the absorbent body 4, the central absorbent portion 43 in the present invention has a front side absorbent sheet 41 and a back side absorbent sheet 42 in the thickness direction Z of the absorbent body 4. And may have a width over the entire width of the absorber 4.

  In the napkin 1, the central absorbent portion 43 (central absorbent sheet 402) is disposed only in a part of the longitudinal direction X of the absorbent body 4 as shown in FIGS. 1 and 3, and the longitudinal direction of the absorbent body 4. Although not arranged over the entire length of X, the central absorbent portion 43 in the present invention may have a length over the entire length in the longitudinal direction X of the absorbent body 4. In addition, the code | symbol 43s in FIG. 3 shows the side edge (end edge of the horizontal direction Y) along the vertical direction X of the center absorption part 43, and was pinched | interposed into these both side edges including a pair of side edges 43s and 43s. The region is the central absorption portion 43.

  In the napkin 1, the central absorbent portion 43 (central absorbent sheet 402) is arranged from the excretory portion facing portion B to a part of the rear portion C in the longitudinal direction X as shown in FIG. For this reason, as shown in FIG. 2, the arrangement | positioning part of the center absorption part 43 is the thick part 47 which the thickness of the absorber 4 was large compared with the periphery and protruded to the wearer's skin side. Thereby, the arrangement | positioning part of the center absorption part 43 in the napkin 1 is easy to closely_contact | adhere to a wearer's skin at the time of wear of the napkin 1, and can contribute to the improvement of the fitting property of the napkin 1, and leak-proof property.

  As shown in FIG. 2, the thick portion 47 of the napkin 1 sandwiches the central absorbent portion 43 composed of the three-folded central absorbent sheet 402 between the front side absorbent sheet 41 and the back side absorbent sheet 42. A total of five layers of absorbent sheets are formed. The thick part 47 is formed in the central part of the absorbent body 4 in the lateral direction Y, and is formed mainly in the excretory part facing part B in the longitudinal direction X of the absorbent body 4. The phrase “mainly formed in the excretory part facing part B” means that 50% or more of the total length of the thick part 47 in the vertical direction X exists in the excretion part facing part B. The thick part 47 is easy to be in close contact with the wearer's skin when the napkin 1 is worn, and can contribute to the improvement of the fit and leakage prevention of the napkin 1.

  The thickness of the thick portion 47 of the absorber 4 is preferably 0.7 mm or more, more preferably 1 mm or more, and preferably 5 mm or less, more preferably 4 mm or less. By setting the thickness of the thick part 47 of the absorbent body 4 in such a range, it becomes easy to achieve both a good wearing feeling, high absorption performance, and high antibacterial effect in the excretory part facing part B. Moreover, when the absorbent article is provided with a wing part like the napkin 1 of this embodiment, it becomes easy to suppress the twist of the absorber in an excretion part opposing part at the time of mounting | wearing.

  Further, the thickness of the absorbent body 4 other than the thick portion 47 is preferably 0.3 mm or more, more preferably 0.5 mm or more, and preferably 3 mm or less, more preferably 2.5 mm or less. By setting the thickness of the portion other than the thick portion 47 of the absorbent body 4 in such a range, it is possible to impart high absorption performance to the napkin 1 and improve the followability to the wearer's movement. The thickness of an absorber and an absorptive sheet is measured by the following method.

<Measurement method of thickness of absorbent sheet and absorber>
The absorptive sheet or absorber to be measured is allowed to stand in a horizontal place so as not to be wrinkled or bent, and the thickness under a load of 5 cN / cm ² is measured. For the thickness measurement in the present invention, a thickness gauge PEACOCK DIAL UPRIGHT GAUGES R5-C (manufactured by OZAKI MFG.CO.LTD.) Was used. At this time, a plan view circular or square plate (acrylic plate having a thickness of about 5 mm) is disposed between the tip of the thickness meter and the measurement portion of the measurement object, and the load becomes 5 cN / cm ^2. Adjust the size of the plate as follows.

  As shown in FIG. 2, the front side absorbent sheet 41 is disposed on the skin facing surface side of the central absorbent portion 43 to cover the entire area of the skin facing surface, and the back side absorbent sheet 42 is center absorbent. It is distribute | arranged to the non-skin opposing surface side of the part 43, and has coat | covered the whole region of this non-skin opposing surface side. In the present embodiment, each of the sheets 41 and 42 is a part of one main body absorbent sheet 401, and one main body absorbent sheet 401 having a relatively long length (width) in the lateral direction Y. Is folded in the lateral direction Y to form a laminated structure including the front surface side absorbent sheet 41 and the back surface side absorbent sheet 42. In the example of FIG. 2, one main body absorbent sheet 401 is overlapped with one end portion and the other end portion in the lateral direction Y of the sheet 401 at the center portion in the lateral direction Y of the non-skin facing surface of the absorbent body 4. It is folded so that the part 49 is located. In the present invention, the front side absorbent sheet 41 and the back side absorbent sheet 42 do not have to be such a single continuous sheet, and may be separate from each other, that is, the main body absorbent sheet 401 is Two sheets 41 and 42 may be included.

  FIG. 4 schematically shows a cross section along the lateral direction Y of the central absorbent portion 43. The central absorbent sheet 402 constituting the central absorbent portion 43 has a first region E in the thickness direction Z (vertical direction in FIG. 4) and a high content of superabsorbent polymer in the first region E. 2 regions F. In the central absorbent sheet 402, the superabsorbent polymer is necessarily contained in the second region F, but the superabsorbent polymer may not be contained in the first region E. The content (basis weight) when the superabsorbent polymer is arranged in the first region E is preferably smaller than that in the second region F.

  In the napkin 1, the first region E forms the skin facing surface and the non-skin facing surface of the central absorbent portion 43, that is, the skin facing surface side surface layer and the non-skin facing surface side surface layer of the central absorbent portion 43. Forming part. The second region F is located inward in the thickness direction Z from the first region E that forms the skin facing surface of the central absorbent portion 43 and the first region E that forms the non-skin facing surface.

  In the napkin 1, the central absorbent portion 43 has a structure in which the central absorbent sheet 402 is laminated in a plurality of layers by folding one central absorbent sheet 402 as shown in FIGS. have. That is, as shown in FIG. 4A, the central absorbent sheet 402 in the central absorbent portion 43 is folded in three at two folded portions b1 and b2 spaced apart in the lateral direction Y of the absorbent body 4. Thus, a three-layer laminated structure (folded structure) is formed. More specifically, the central absorbent sheet 402 is arranged on the back sheet 3 side (on the non-skin facing side of the absorbent body 4) at the first bent portion b <b> 1 counting from one end edge e <b> 1 along the longitudinal direction X of the central absorbent sheet 402. The other end edge e2 opposite to the one end edge e1 is arranged inside the three-layer laminated structure in the second bent portion b2 counted from the one end edge e1. It is folded to the surface sheet 2 side (the skin facing surface side of the absorber 4), and is folded in a spiral shape as a whole.

  Thus, as shown in FIG. 4, the laminated structure of the central absorbent portion 43 formed by folding one central absorbent sheet 402 in the lateral direction Y is the skin facing surface side in the laminated structure, that is, An upper sheet 43a positioned on the top sheet 2 side, a non-skin facing surface side in the laminated structure, that is, a lower sheet 43b positioned on the back sheet 3 side, and an intermediate sheet 43c positioned between both the sheets 43a and 43b It is comprised including. The central absorbent portion 43 shown in FIG. 4 is a surface in which the upper surface S1 is directed to the skin facing surface side, that is, the surface sheet 2 side, and the lower surface S2 is the non-skin facing surface side, It is a surface directed toward the back sheet 3 side. In the example shown in FIG. 4, the entire central absorbent portion 43 has a structure in which the central absorbent sheet 402 is laminated in a plurality of layers. However, in the present invention, the central absorbent portion 43 is central absorbent. The sheet 402 may have a single layer structure in which the sheets 402 are not stacked.

  The central absorbent portion 43 includes a highly absorbent polymer. That is, the central absorbent sheet 402 constituting the central absorbent portion 43 includes the superabsorbent polymer 46 as shown in FIG. And the center absorption part 43 has more weight (what is called basic weight) of the superabsorbent polymer per unit area than the surface side absorbent sheet 41 and the back surface side absorbent sheet 42. FIG. Here, regarding the basis weight of the superabsorbent polymer, it is the central absorbent portion 43 having the laminated structure (folded structure) that is compared with the front-side absorbent sheet 41 and the back-side absorbent sheet 42. This is not the central absorbent sheet 402 constituting the laminated structure. Thus, in the laminated structure of the absorber 4 including the front side absorbent sheet 41, the back side absorbent sheet 42, and the central absorbent portion 43 located between both sheets 41, 42, the basis weight of the superabsorbent polymer. With respect to the above, the size relationship of “sheets 41, 42 <center absorption part 43” is established, so that the transfer of body fluid from the both sheets 41, 42 side to the center absorption part 43 side is promoted. Both sheets 41 and 42 may not contain a superabsorbent polymer, respectively. When both sheets 41 and 42 contain a superabsorbent polymer, the ratio between the basis weight of the superabsorbent polymer of each of the sheets 41 and 42 and that of the central absorbent portion 43 is based on the former <the latter / the latter Is preferably 1/4 or more, more preferably 3/10 or more, and preferably 7/10 or less, more preferably 3/4 or less.

  As shown in FIG. 5, the central absorbent sheet 402 constituting the central absorbent portion 43 includes a superabsorbent polymer 46, and the first region E and the thickness direction Z (vertical direction in FIG. 5) of the sheet The second region F has a higher content of the superabsorbent polymer 46 than the first region E. Both regions E and F each contain a fiber material 48. The first region E and the second region F extend over the entire region in the direction parallel to the surface of the central absorbent sheet 402. The first region E and the second region F may be layered so that the boundary between the first region E and the second region F is clear, or one fiber material 48 at the boundary between the first region E and the second region F. May enter the inter-fiber gap of the other fiber material 48, for example, so that the interface between the two may be unclear.

  As the superabsorbent polymer 46 contained in the central absorbent sheet 402, generally a particulate polymer is used. The shape of the particulate superabsorbent polymer is not particularly limited, and may be any of a lump shape, a bowl shape, a fiber shape, or an indeterminate shape other than a spherical shape as shown in FIG. As the superabsorbent polymer, generally, a polymer or copolymer of acrylic acid or an alkali metal acrylate can be used. Examples thereof include polyacrylic acid and salts thereof and polymethacrylic acid and salts thereof. As the polyacrylate and polymethacrylate, sodium salts can be preferably used. In addition, acrylic acid or methacrylic acid, maleic acid, itaconic acid, acrylamide, 2-acrylamido-2-methylpropanesulfonic acid, 2- (meth) acryloylethanesulfonic acid, 2-hydroxyethyl (meth) acrylate, styrenesulfonic acid, etc. It is also possible to use a copolymer obtained by copolymerizing the above-mentioned comonomer within a range that does not deteriorate the performance of the superabsorbent polymer.

  Examples of the fiber material 48 included in the central absorbent sheet 402 include, for example, a hydrophilic fiber obtained by hydrophilizing a hydrophobic fiber, and a hydrophilic fiber that itself is hydrophilic. Particularly preferred are those which are themselves hydrophilic and have water retention. Preferred examples of hydrophilic fibers include natural fibers, cellulosic regenerated fibers, and semi-synthetic fibers. Examples of hydrophilic fibers having water retention include cellulosic fibers such as wood pulp fibers, rayon fibers, cotton fibers, and cellulose acetate fibers. Cellulose fibers can be used singly or in combination of two or more. Examples of cellulosic fiber pulp include wood pulp such as softwood kraft pulp and hardwood kraft pulp; and non-wood pulp such as cotton pulp and straw pulp. As the cellulosic fiber, a regenerated cellulose fiber such as a cross-linked cellulose fiber (pulp fiber) obtained by cross-linking cellulose molecules within or between molecules with an appropriate cross-linking agent, or a rayon fiber having improved cellulose crystallinity is used. You can also

  As the fiber material 48 included in the central absorbent sheet 402, a synthetic fiber such as a thermoplastic fiber can be used together with or in place of the cellulosic fiber. As the thermoplastic fiber, for example, a single fiber formed using a single synthetic resin such as polyethylene, polypropylene, polyester, or polyurethane, or a synthetic resin such as a composite of two or more of these is used. A composite fiber such as a core-sheath type or a side-by-side type composite fiber formed using two or more kinds of synthetic resins can also be used.

  In the second region F, an antibacterial agent 8 is further arranged in addition to the superabsorbent polymer 46 and the fiber material 48 as shown in FIG. In the napkin 1, the second region F is disposed over the entire area in the surface direction of the central absorbent sheet 402 constituting the central absorbent portion 43, and the antibacterial agent 8 is disposed over the entire second region F. Therefore, in the laminated structure of the central absorbent portion 43 (central absorbent sheet 402), as shown in FIG. 4A, the second region F of the upper sheet 43a, the second region F of the intermediate sheet 43c, and the lower sheet The antibacterial agent 8 is disposed in all of the second region F of 43b, and these antibacterial agents 8 include the first region E that forms the skin facing surface of the central absorbent portion 43 and the non-skin of the central absorbent portion 43. It is located between the first region E forming the facing surface.

From the viewpoint of increasing the contact area with the body fluid and improving the antibacterial effect, the antibacterial agent disposed in the second region F is distributed throughout the second region F in the direction parallel to the surface of the central absorbent sheet 402. Preferably it is. The basis weight of the antimicrobial agent can be suitably determined according to the type of antimicrobial agent, an example, preferably 0.005 g / ^{m 2} or more, more preferably 0.03 g / ^{m 2} or more, And it is preferably 5.0 g / m ² or less, more preferably 3.0 g / m ² or less.

  From the same viewpoint, the content of the antibacterial agent in the central absorbent portion 43 (central absorbent sheet 402) is preferably 0.001% by mass or more, more preferably 0.001% by mass relative to the total mass of the central absorbent portion 43. It is 01% by mass or more, and preferably 12% by mass or less, more preferably 5% by mass or less.

  In the central absorbent sheet 402, the second region F always contains an antibacterial agent, but the first region E may or may not contain the antibacterial agent. The content (basis weight) when the antibacterial agent is disposed in the first region E may be smaller than that in the second region F. Since the napkin 1 exhibits an antibacterial effect by a halo effect by the second region facing portion 2F described later in the laminated structure of the central absorbent sheet 402, basically, it is not necessary to arrange an antibacterial agent in the first region E. .

  In the central absorbent sheet 402, the first region E (a region that does not substantially contain an antibacterial agent) and the second region F (a region that contains the antibacterial agent) are in the thickness direction over the entire surface direction of the sheet 402. They may overlap each other, or may overlap each other in the thickness direction only in a part of the sheet 402 in the surface direction. In the napkin 1, the former is adopted as shown in FIG. 4A, that is, in the central absorbent sheet 402, the skin facing surface and the non-skin facing surface of the central absorbent portion 43 over the entire area of the sheet 402. And a second region F that overlaps the first region E in the thickness direction Z is provided.

  As one of the main features of the napkin 1, a second region facing portion 2F in which the second regions F are opposed to each other without the first region E is formed in the laminated structure of the central absorbent sheet 402. A point is mentioned. That is, as described above, the central absorbent portion 43 of the absorbent body 4 has a structure in which the central absorbent sheet 402 is laminated in three layers, thereby substantially preventing antibacterial activity as shown in FIG. 1st area | region E which does not contain an agent, and 2nd area | region F containing an antibacterial agent are 1st area | region E, 1st area | region E from the skin opposing surface side in the thickness direction Z of the center absorption part 43 toward the non-skin opposing surface side. 2 areas F, 1st area E, 2nd area F, 2nd area F, and 1st area E occur in order, and the skin opposing surface and non-skin opposing surface of central absorption part 43 are all 1st area E. When formed, the black-colored portion of FIG. 4B becomes the second region facing portion 2F in which the second regions F containing the antibacterial agent are opposed to each other without the first region E interposed therebetween. Yes. In the example shown in FIG. 4B, the second region facing portion 2F includes the second region F of the intermediate sheet 43c (the second region F located on the side relatively closer to the wearer's skin) and the lower sheet 43b. 2nd area | region F (2nd area | region F located in the relatively far side from a wearer's skin), and both 2nd area | regions F and F are closely_contact | adhered and laminated | stacked. The second region facing portion 2F is present in the entire area of the arrangement region of the central absorbent portion 43 in plan view, and is located in the central portion in the lateral direction Y of the excretory portion facing portion B.

  While the central absorbent sheet 402 has the above-described configuration, the configuration of the main body absorbent sheet 401 (sheets 41 and 42) is not particularly limited, and may be a single-layer structure sheet. A sheet having a laminated structure similar to 402 may be used. The main body absorbent sheet 401 is typically composed mainly of a fiber material, and may be paper, various nonwoven fabrics, or a composite sheet of paper and nonwoven fabric. The main body absorbent sheet 401 (sheets 41 and 42) may be configured in the same manner as the central absorbent sheet 402 except that the antibacterial agent is not disposed. For example, in the thickness direction, the first region, The superabsorbent polymer content may have a second region that is greater than the first region, and a deodorant to be described later may be provided. Moreover, the 1st area | region (area | region with relatively little content of a superabsorbent polymer) of the main body absorbent sheet 401 may form the skin opposing surface and non-skin opposing surface of the absorber 4. FIG. When the main body absorbent sheet 401 has the first region and the second region in the thickness direction, the sheet 401 having such a laminated structure forms, for example, the first sheet that constitutes the first region and the second region. After the second sheet is individually manufactured by any method such as wet papermaking method or dry papermaking method, they are combined and integrated by adhesives, binder fibers, adhesive strength of swollen superabsorbent polymer, etc. Can be manufactured.

  The thickness of each of the absorbent sheets 401 and 402 described above is preferably 0.1 mm or more, more preferably from the viewpoint of providing a napkin 1 having sufficient liquid diffusibility and liquid retention and having a good wearing feeling. Is 0.3 mm or more, and preferably 2 mm or less, more preferably 1.5 mm or less.

  In the central absorbent portion 43, the number of the laminated layers of the central absorbent sheet 402 constituting it is preferably 2 or more, more preferably 3 or more, and preferably 7 or less, more preferably 5 or less. Moreover, the absorber 4 has the absorption capacity | capacitance and absorption rate at the time of bodily fluid discharge | emission that the sum total number of lamination | stacking of each of the surface side absorbent sheet 41, the back surface side absorbent sheet 42, and the center absorbent sheet 402 which comprises the center absorption part 43 is. In addition, from the viewpoint of a feeling of incongruity at the time of wearing, it is preferably 3 or more, more preferably 5 or more, and preferably 10 or less, more preferably 7 or less.

The napkin 1 will be further described. In the napkin 1, it is preferable that an adhesive is applied and fixed between the top sheet 2 and the absorber 4 and between the absorber 4 and the back sheet 3. In addition, the layers of the laminated absorbent sheets 401 and 402 constituting the absorbent body 4 may or may not be adhered to each other. However, in use, they are adhered from the viewpoint of twisting or shifting of the absorbent body. It is preferable that it is joined by the agent. The adhesive can be applied using a known means such as a slot coat gun, a spiral spray gun, a spray gun, or a dot gun. In the napkin 1, the adhesive can be applied in a spiral shape using a spiral spray gun. preferable. As the adhesive to be applied, for example, a hot melt adhesive is preferably used. The application amount of the hot melt adhesive is preferably 1.5 g / m ² or more and 10 g / m ² or less.

  In the napkin 1, as shown in FIGS. 1 and 2, the surface sheet 2 and the absorbent body 4 are integrally formed on the skin-facing surface of the absorbent main body 5 so as to be recessed toward the back sheet 3. A compressed groove 9 is formed. In the compressed groove 9, both the surface sheet 2 and the absorbent body 4 are recessed, and the density of each fiber that is a constituent member with respect to the surface sheet 2 and the absorbent body 4 in the formation position of the compressed groove 9 is the periphery of the compressed groove 9. It is higher than that in the club. The compressed groove 9 may be a continuous line or a discontinuous line such as a broken line. For example, the compressed groove 9 may be composed of a row formed by a number of discontinuous point embosses.

  The napkin 1 has a vertical squeezing groove 92 extending in the vertical direction X as a squeezing groove 9 on each of both side portions (both ends in the horizontal direction Y) along the vertical direction X of the excretory part facing part B. Each of A and the rear part C has a lateral pressing groove 91 extending in the lateral direction Y as the pressing groove 9. The presence of the vertical squeezing groove 92 is particularly effective in preventing the leakage of the excreted body fluid in the lateral direction Y and preventing leakage, and in the central absorbent portion 43 (second region F) containing the antibacterial agent. It is also effective in collecting bodily fluids.

The napkin 1 according to the present embodiment is used by being fixed to a crotch portion or the like of a shorts in the same manner as a normal sanitary napkin.
In the napkin 1, the thickened portion 47 of the absorbent body 4 that is thicker than the peripheral portion is located in the excretory portion facing portion B where body fluid such as menstrual blood concentrates. The thick part 47 is in close contact with the excretion part of the wearer and directly receives the body fluid excreted from the excretion part. The body fluid thus received mainly through the thick part 47 sequentially passes through the top sheet 2, the second sheet 21, and the top side absorbent sheet 41 and is absorbed by the central absorbent part 43. Therefore, there is a concern that the central absorption portion 43 is particularly prone to bacterial growth and becomes a source of malodor.

  On the other hand, in the napkin 1, as shown in FIG. 4, as described above, the two layers of the second regions F and F including the antibacterial agent are contained in the laminated structure of the central absorbent portion 43 (central absorbent sheet 402). A second region facing portion 2F having a configuration in which the two are arranged in close proximity to each other is formed, and thereby a region (also referred to as a halo or the like) that can effectively inhibit the growth of bacteria (bacterial inhibition zone) is the second region. Since it extends not only in the planar direction of the absorbent body 4 but also in the thickness direction with the opposing portion 2F as the center, the concern has been eliminated, and the growth of bacteria is effectively suppressed, and the generation of malodor is effective. Is suppressed. Therefore, the napkin 1 can be used safely for a long period of time without worrying about the smell.

  Further, in the napkin 1, a high antibacterial effect can be obtained by arranging an antibacterial agent in the central absorbent portion 43, which is a part of the absorber 4, so that it is not necessary to dispose the antibacterial agent uniformly throughout the absorber 4. Also good. Therefore, according to the napkin 1, an excellent antibacterial effect can be obtained even with a relatively small amount of antibacterial agent, and generation of malodor due to bacteria and other troubles due to bacteria can be efficiently suppressed for a long time. In particular, when the absorbent body 4 is manufactured without arranging the antibacterial agent on the surface-side absorbent sheet 41, the antibacterial agent is difficult to migrate from the napkin 1 to the wearer's skin during use. It becomes difficult to come into contact with the resident bacteria present on the skin, skin troubles hardly occur, and the feeling of use becomes good.

  Moreover, since the antibacterial effect by the halo centering on the 2nd area | region opposing part 2F mentioned above works strongly, so that it is close to an antibacterial agent, such an effect is utilized more effectively and the predetermined effect of this invention is more reliably exhibited. In order to do so, it is effective to concentrate the excreted body fluid such as menstrual blood on the second region facing portion 2 </ b> F existing inside the central absorption portion 43. In this respect, as described above in the napkin 1, 1) the central absorbent portion 43 is more unit area than the front side absorbent sheet 41 and the back side absorbent sheet 42 disposed so as to contain the central absorbent portion 43. Since the weight (basis weight) of the superabsorbent polymer is large, the movement of body fluid from both sheets 41 and 42 side to the central absorbent portion 43 side is promoted, and 2) the surface layer portion of the central absorbent portion 43 is formed. Since the second region F positioned inward in the thickness direction from the first region E contains a larger amount of superabsorbent polymer than the first region E, the body fluid present in the surface layer portion is contained in the second region F. The superabsorbent polymer can be drawn into the central absorbent portion 43 and can be quickly transferred to the second region facing portion 2F and the vicinity thereof. Thus, in the napkin 1, the body fluid excreted by the wearer is easily concentrated on the second region facing portion 2 </ b> F of the central absorbent portion 43 by adopting the above 1) and 2).

The second region of the central absorbent portion 43 (central absorbent sheet 402) from the viewpoint of more surely exerting the above-described operational effects (effect of attracting body fluid toward the second region F). The superabsorbent polymer disposed in F is preferably distributed over the entire second region F in a direction parallel to the surface of the central absorbent sheet 402. From the same viewpoint, the content of the superabsorbent polymer in the second region F is preferably 5 g / m ² or more, more preferably 15 g / m ² or more, and preferably 60 g / m ² or less as the basis weight. More preferably, it is 40 g / m ² or less. If the content of the superabsorbent polymer in the second region F is too small, it is not meaningful to use the polymer. On the other hand, if the content is too large, absorption inhibition occurs due to gel blocking, and the second region F has a high antibacterial effect. Is difficult to be absorbed. As a result, not only a sufficient antibacterial effect is not obtained, but also liquid return and leakage may occur. In addition, as above-mentioned in the 1st area | region E, it is preferable that a superabsorbent polymer is not contained, or a small amount of superabsorbent polymers are contained rather than the 2nd area | region F. FIG.

  Moreover, in the napkin 1, as shown in FIG.2 and FIG.4, the surface side absorptive sheet 41 and the back surface side absorptive sheet 42, respectively, and the skin-opposing surface and the non-skin-facing surface of the central absorbent sheet 402 are formed. When the first region E is in contact, the body fluid is more smoothly transferred from the two sheets 41 and 42 to the central absorbent portion 43, and the antibacterial effect by the halo centering on the second region facing portion 2F is effectively utilized. Therefore, the first region E on the skin facing surface side (that is, the first region E of the upper sheet 43a adjacent to the sheet 41 in the thickness direction of the absorbent body 4) is the central absorbent portion 43 of the sheet 41 in contact therewith. It is preferable that the density of the fiber material is higher than the surface side adjacent to the surface side (the central absorbent portion side of the surface side absorbent sheet 41), and the first region E on the non-skin facing surface side (that is, the absorber 4). In the thickness direction The first region E of the lower sheet 43b adjacent to the sheet 42) is closer to the surface side adjacent to the central absorbent portion 43 of the sheet 42 in contact therewith (the central absorbent portion side of the back side absorbent sheet 42), It is preferable that the density of the fiber material is high. Here, “the central absorbent portion side of the surface side absorbent sheet 41” means preferably 50% of the thickness of the sheet 41 in the thickness direction of the sheet 41 from the surface adjacent to the central absorbent portion 43 of the sheet 41, More preferably, it means an area over 30%. Further, “the central absorbent portion side of the back-side absorbent sheet 42” means preferably 50% of the thickness of the sheet 42 in the thickness direction of the sheet 42 from the surface adjacent to the central absorbent portion 43 of the sheet 42, more preferably. Means an area spanning 30%. With such a configuration, the former is relatively low density and the latter is relatively low between the central absorbent portion side of the front side absorbent sheet 41 or the central absorbent portion side of the back side absorbent sheet 42 and the central absorbent portion 43. As a result of the formation of a dense and dense gradient, body fluid can quickly migrate from the former to the latter. It should be noted that body fluid such as menstrual blood excreted by the wearer of the napkin 1 normally moves from the surface-side absorbent sheet 41 to the central absorbent portion 43. For example, a large amount of body fluid is excreted at once, and the large amount of body fluid However, body fluid is transferred from the back side absorbent sheet 42 to the central absorbent portion 43 when the back side absorbent sheet 41 reaches the back side absorbent sheet 42 through the compressed groove 9 or the slit 45 described later. Can migrate. The density of the fiber material is measured by the following method.

<Measuring method of density of fiber material>
Using a microscope (for example, “VHX-1000” manufactured by KEYENCE Corporation) or a scanning electron microscope (for example, JCM-5100 manufactured by JEOL Ltd.), a cut surface along the thickness direction of the measurement target (absorbent sheet) Is magnified to obtain image data of the cut surface. The magnification at the time of observation is such a magnification that about 10 to 70 fiber cross sections can be observed, and is usually a magnification of 20 to 200 times. In the observation visual field of the cut surface, the area occupied by the fibers per fixed visual field area (0.02 mm ² ) is measured by image analysis. Specifically, the obtained image is binarized by setting a threshold value at a brightness boundary between a fiber and a portion where no fiber exists using image processing software such as ImageJ. In general, when binarized with white and black, the fiber is white, and the part where the fiber is not present is black, so in the thickness direction of the measurement target such as the absorbent sheet, the region with many white parts is the first. The two regions F and the region with many black portions can be identified as the first region E. Next, each of the area having white and the area having black in the constant visual field area (0.02 mm ² ) is calculated and converted into the area of fibers per unit area (1 mm ² ), which is the density of the fiber material ( mm ² / mm ² ). In addition, the measurement of the density of this fiber material is carried out by measuring the first region E of the measurement target (central absorbent sheet 402), the central absorbent portion side of the front side absorbent sheet 41, and the central absorbent portion side of the back side absorbent sheet 42. It carries out at each arbitrary three places, and let the average value be the fiber density of the said area | region.

  In general, the density of the fiber material in this type of absorbent sheet is affected by the type of fiber material, the fiber diameter, the content, and the like. It becomes possible to establish a magnitude relationship of “the first region E of the sheet 402> the side of the central absorption part of the sheets 41 and 42”. For example, the density of the fiber material in the region is increased by beating and fibrillating the fiber, using a thin fiber material with a small fiber diameter, and the density of the region is increased when using a fiber material with a large fiber diameter. Therefore, it is conceivable that the first region E having a relatively high density is mainly composed of a fibrillated fiber material and / or a thin fiber material having a small fiber diameter. In addition, when the central absorbent sheet 402 is manufactured by combining and integrating the first sheet constituting the first region E and the second sheet constituting the second region F, before the combining and integration, By compressing the first sheet by pressing it in the thickness direction or the like, the density of the fiber material in the first region E in the sheet 402 that is a manufacturing result is set to that of the sheets 41 and 42 on the side of the central absorbent portion. Can be higher.

  In the napkin 1, the density of the fiber material in the first region E and the second region F constituting the central absorbent sheet 402 is higher in the second region F. As described above, when the magnitude relationship of “first region E <second region F” is established with respect to the density of the fiber material, the transition of the body fluid due to the density gradient is promoted in the central absorbent sheet 402, and excreted menstrual blood Or the like can concentrate on the second region facing portion 2F existing inside the central absorbent portion 43. When such a magnitude relationship is established, the central absorbent portion 43 (central absorbent sheet 402) has the density of the fiber material in the second region F measured by the method described above in the first region E measured by the same method. The density of the fiber material is preferably 1.2 times or more, more preferably 2 times or more, and preferably 10 times or less, more preferably 7 times or less.

  In the napkin 1, since the surface-side absorbent sheet 41 is disposed on the skin-facing surface side of the central absorbent portion 43, the body fluid once absorbed by the central absorbent portion 43 is unlikely to return to the wearer's skin. Return is effectively prevented. As described above, in the absorbent body 4, the body fluid is smoothly transferred from the outer side in the thickness direction (front-side absorbent sheet 41, the rear-side absorbent sheet 42) to the inner side in the thickness direction (central absorbent portion 43), and Since the liquid does not easily return, the napkin 1 is excellent in liquid absorption capacity and dry feeling, and hardly leaks.

  Further, as described above, the central absorbent portion 43 in the napkin 1 is configured to be laminated in a plurality of layers by folding one central absorbent sheet 402, and as a result, as shown in FIG. Also on both side portions along the longitudinal direction X of the central absorbent portion 43, the outermost layer is composed of the first region E and is inward of the outermost layer, similarly to the skin facing surface and the non-skin facing surface of the central absorbent portion 43. Where the second region F is located, for example, a large amount of bodily fluid is excreted at once, so that the bodily fluid does not pass through the skin-facing surface of the central absorbent portion 43 and directly follows the longitudinal direction X of the central absorbent portion 43. Even when it reaches both sides, the same effect as when it passes through the skin facing surface is exhibited.

  It is preferable that the fragrance | flavor is distribute | arranged to the central absorbent sheet 402 which comprises the central absorption part 43. FIG. In other words, the central absorbent sheet 402 is preferably scented. Thereby, even if bad odor is generated from the napkin 1 in use, the bad odor is effectively deodorized by the masking effect and / or the harmony effect by the fragrance.

  Although the arrangement | positioning part of a fragrance | flavor in the center absorption part 43 is not restrict | limited in particular, It is preferable to distribute a fragrance | flavor inside the center absorption part 43 from a viewpoint of volatilization suppression of the fragrance | flavor component of a fragrance | flavor. For example, in the napkin 1, as shown in FIG. 4, the first region E of the central absorbent sheet 402 forms the outer surface (surface layer) of the central absorbent portion 43, and the second region F of the sheet 402 is the central absorbent portion. Since it is located inside 43, it is preferable that a fragrance | flavor is distribute | arranged to the 2nd area | region F. FIG. Thereby, the outstanding deodorizing performance by a fragrance | flavor can be expressed stably over a long period of time.

As the fragrance, any fragrance that can perceive the fragrance in an environment of normal temperature and pressure is not particularly limited as long as it can achieve such purpose by volatilizing the fragrance component into the atmosphere at atmospheric pressure. The thing conventionally used in absorbent articles, such as a disposable diaper, can be used. Examples of the fragrances include fragrances having a green herbal-like fragrance described in JP-A-2007-244664, plant extract, citrus extract and the like. Content of the fragrance | flavor in the center absorption part 43 (central absorbent sheet 402) is not restrict | limited in particular, It can set suitably according to the kind etc. of fragrance | flavor. For example, the content of the fragrance in the developed central absorbent sheet 402 is preferably 0.1 g / m ² or more and 1 g / m ² or less, more preferably 0.2 g / m ² or more and 0.6 g / m ² or less. is there.

  For example, the central absorbent sheet 402 constituting the central absorbent portion 43 constitutes the first region E after applying the antibacterial agent in the manufacturing process of the second sheet constituting the second region F. It can be manufactured by combining and integrating with the first sheet. As a method of applying the antibacterial agent to the second sheet, 1) a method of applying a solution or dispersion containing the antibacterial agent to the second sheet before bonding with the first sheet, 2) the first sheet and the second sheet A method in which a solution or dispersion containing an antibacterial agent is applied to the surface on the second sheet side of the composite sheet formed by combining and integrating with the sheet, and then heated or naturally dried. The method of spraying or spraying a particulate antibacterial agent from the sheet side is mentioned. Examples of the method for applying a solution or dispersion containing an antibacterial agent include a method using a known liquid coating apparatus such as a spray method, a transfer method, a die coating, a gravure coating, an ink jet method, and a screen printing. . In addition, the first sheet and the second sheet are joined and integrated, for example, after each sheet is individually manufactured by an arbitrary method such as a wet papermaking method or a dry papermaking method, and then the adhesive sheet, the binder fiber, A method of bonding and integrating by the adhesive force of the swollen superabsorbent polymer is exemplified. As another method of combining and integrating the first sheet and the second sheet, a solution or dispersion containing an antibacterial agent is applied to the first sheet in a dry state, and the first sheet in a wet state (water-containing state) is obtained. The wet first sheet and the wet (hydrated) second sheet, which are separately wet-made, are superposed, pressed in the thickness direction, and then dried to bond and integrate. The method of letting it be mentioned. In such another method, when the two sheets are overlapped and pressed, the antibacterial agent that has been applied to the first sheet before bonding is added to the second sheet due to excess moisture and pressurization contained in the second sheet. Since it elutes to the side, the 2nd field F in which an antibacterial agent was arranged is formed by drying after pressurization.

As the antibacterial agent used in the present invention, those used for antibacterial applications in absorbent articles such as sanitary napkins can be used without particular limitation. For example, an antibacterial metal, an antibacterial metal support, an organic antibacterial agent and the like can be mentioned.
Examples of the antibacterial metal include copper, silver, gold, lead, nickel, tin, zinc, iron, and zirconium.
Examples of the antibacterial metal support include silver zeolite, divinylbenzene-2-vinylpyridine-2-vinylpyridine silver copolymer (for example, those described in JP-A-2006-307404), aluminum / silver / sodium nitrate silicate. (For example, those described in JP-A-2005-232654), a composite of silicon dioxide / zinc oxide / aluminum oxide supporting silver or zinc (specifically, a metal-substituted cancrinite-like mineral supporting an antibacterial metal) And water-insoluble or water-insoluble antibacterial agents such as silver zirconium phosphate and a mixture of silver and zinc zeolite.
As the organic antibacterial agent, a quaternary ammonium salt is preferable. Among them, poorly water-soluble benzalkonium chloride, cetyl phosphoric acid benzalkonium and the like are preferable.

  The antibacterial agent used in the central absorbent portion 43 will be further described. Is the antibacterial agent disposed in each part (first region E, second region F) of the central absorbent portion 43 (i) poorly water-soluble or water-insoluble? Or (ii) It is preferable that the arrangement part of the antibacterial agent is arranged in a state in which it is difficult to move by the water moving in the thickness direction. In this specification, the case where at least one of the above (i) and (ii) is satisfied is also referred to as “having poor mobility”. That is, it is preferable that the antibacterial agent arranged in each part (the first region E and the second region F) of the central absorbent portion 43 has poor water mobility.

  The main factors affecting the water mobility are the properties of the antibacterial agent itself and the arrangement form of the antibacterial agent. The former has a particularly large influence, and specifically, it is considered to be solubility in water. That is, whether or not the antibacterial agent can exist in a predetermined portion (for example, the second region F) with poor water mobility depending on whether the antibacterial agent is water-soluble, hardly water-soluble, or water-insoluble. Can be determined. In general, the lower the solubility of the antibacterial agent in water, the easier it is for the antibacterial agent to have poor water mobility, that is, the poorly water-soluble or water-insoluble antibacterial agent has relatively low water mobility. It's easy to do. Therefore, in the present invention, (i) is included in the concept that the antibacterial agent has poor mobility.

  With regard to (i), the antibacterial agent is poorly water-soluble means that the solubility in 100 g of ion-exchanged water at 25 ° C. is less than 20 g, and the antibacterial agent is insoluble in water when the solubility is 0. .Means less than 1 g. As is clear from this definition, the water-insoluble antibacterial agent is also poorly water-soluble. Incidentally, the fact that the antibacterial agent is water-soluble means that the solubility is 20 g or more. The solubility of the poorly water-soluble or water-insoluble antibacterial agent per 100 g of ion-exchanged water at 25 ° C. is preferably 10 g or less, more preferably 1 g or less.

  The solubility can be measured by the following method. Thoroughly dry measurement target (antibacterial agent) is added to 100 g of ion-exchanged water at 25 ° C. in a 200 mL beaker, a 20 mm long and 7 mm wide stirrer chip is added, and the magnetic stirrer is stirred at 600 rpm. The amount immediately before stirring for 1 hour cannot be dissolved is defined as the solubility of the antibacterial agent in 25 ° C. water. As the magnetic stirrer, HPS-100 manufactured by AS ONE Corporation can be used.

  As the antibacterial agent satisfying the above (i), that is, the poorly water-soluble or water-insoluble antibacterial agent, the above antibacterial metal support can be exemplified. The antibacterial metal support is hardly water-soluble or water-insoluble. Even if the supported metal is water-soluble, the carrier (preferably porous particles) supporting the antibacterial metal is hardly water-soluble or water-soluble. Means insoluble.

  On the other hand, regardless of the nature of the antibacterial agent itself (solubility in water), the antibacterial agent can exist in a predetermined portion with water mobility even by devising the arrangement form of the antibacterial agent. For example, if the density of the fiber material is relatively high in the second region F of the central absorbent portion 43 (central absorbent sheet 402) as compared to the first region E, the first region E in the second region F. Since the antibacterial agent is less likely to fall off due to the transfer of body fluids, the antibacterial agent moves to the second region F even if the antibacterial agent disposed in the second region F is relatively soluble in water. And may be difficult to drop out from the second region F due to the transfer of body fluids. That is, if the location of the antibacterial agent is the second region F in which the density of the fiber material is relatively high, even if the antibacterial agent is water-soluble, it can be present in the second region F with water mobility. Therefore, it is possible to use a water-soluble antibacterial agent. Therefore, in the present invention, (ii) is included in the concept that the antibacterial agent has poor mobility.

  It is preferable that the antibacterial agent satisfying the above (ii) is difficult to move by “a small amount of water” that moves the arrangement portion in the thickness direction. The “small amount” as used herein is typically the same as the amount of body fluid such as menstrual blood that is normally excreted by a normal wearer of the absorbent article. For example, the amount of menstrual blood excreted at a time when the amount of menstrual blood is large is about 2 to 5 cc on average although there are individual differences. In addition, when water moves in the thickness direction of the antibacterial agent arrangement part, excessive pressure is applied to the arrangement part (for example, so as to greatly exceed the body pressure normally applied to the absorbent article when this type of absorbent article is worn). (Ii) may be satisfied in a state where no proper pressure is applied. As a specific preferable range of “satisfying (ii)”, a syringe is used from a position 1 cm upward from the region where the antibacterial agent is present in the absorbent sheet (for example, the second region F). When 5 cc of physiological saline is dropped over 1 second ± 0.5 seconds, the antibacterial agent remaining in the region after the dropping is 50 mass of the amount of the antibacterial agent present in the region before dropping. % Or more is preferable, and 70% by mass or more is particularly preferable. The amount of the antibacterial agent before and after the physiological saline is dropped in the absorbent sheet can be quantified using a conventional method. For example, the extraction method and the quantification method select conditions such as the extraction solvent depending on the type of the antibacterial agent, and high performance liquid chromatography, This method can be used.

  The antibacterial agent satisfying the above (ii), which is disposed in each part (first region E, second region F) of the central absorbent portion 43, has an excess amount of water (in excess of the usual excretion amount in the vicinity) ( Body fluid), and has a poor mobility, so that the body fluid such as menstrual blood thickens the central absorbent portion 43 when the napkin 1 is used. Even if it moves in the direction, the inconvenience that the antibacterial agent moves due to the movement of the bodily fluid and drops from the region (for example, the second region F) originally arranged is suppressed, and the predetermined effect by the antibacterial agent is more reliably achieved. Will come to be.

  The absorbent body 4 preferably further contains a deodorant in addition to the antibacterial agent described above, and the central absorbent portion 43 (central absorbent sheet 402) particularly preferably contains a deodorant. By adding a deodorant to the absorbent body 4 including the central absorbent portion 43, generation of an unpleasant odor due to bacteria can be more effectively suppressed by combination with an antibacterial agent. The antibacterial agent has an effect of suppressing the generation of odor due to bacteria, but the deodorant is useful for suppressing the odor that does not depend on the bacterium and the odor generated before the antibacterial agent acts.

  When the central absorbent portion 43 (central absorbent sheet 402) includes a deodorant, the deodorant may be included only in the first region E, or may be included only in the second region F. Although both the 1st and 2nd area | regions E and F may contain, it is preferable that the 1st area | region E with relatively little content of a superabsorbent polymer contains the deodorizer. As described above, the second region F in which the content of the superabsorbent polymer is relatively high due to the presence of the deodorant in the first region E that does not substantially contain the superabsorbent polymer. The deodorant can act on the body fluid not retained in the first region E, and the generation of an unpleasant odor due to the bacteria can be effectively suppressed.

  The content of the deodorant in the central absorbent portion 43 (central absorbent sheet 402) is preferably 0.2% by mass or more, more preferably 0.5% by mass or more, based on the total mass of the central absorbent unit 43. And, Preferably it is 2.0 mass% or less, More preferably, it is 1.0 mass% or less.

  As a deodorant, it is a substance that directly acts on an odor (odor substance) itself, that is, a substance that can adsorb, neutralize, decompose, etc. the odor (odor substance) and exhibit a deodorizing effect. The thing generally used for the deodorizing use also in the field | area can be used. Examples of the deodorant used in the present invention include porous particles and a water-soluble pH buffer.

  Porous particles as a deodorant are particles having a large number of pores at least on the particle surface, and can volatilize, adsorb and / or include volatile odorous components in the pores. Examples of the material of the porous particles include an organic compound, an inorganic compound, a polymer thereof, or a combination thereof. Specific examples thereof include synthesis of acrylic polymers such as porous methacrylic acid polymer and porous acrylic acid polymer, aromatic polymers such as porous divinylbenzene polymer and porous pyridine copolymer, and copolymers thereof. Porous polymer; natural porous polymer such as chitin and chitosan; zinc oxide, activated carbon, silica, silicon dioxide (silica gel), calcium silicate, aluminosilicate compound, high silica zeolite (hydrophobic zeolite), sepiolite, cancrinite , Zeolite, and metal-supported porous materials such as inorganic porous materials such as hydrated zirconium oxide, and preferably contains at least one selected from the group consisting of these. The odor component derived from excretory fluids such as urine and menstrual blood to be deodorized is a mixture of a plurality of components such as ammonia, amines, fatty acids, hydrogen sulfide and mercaptans. Generally, since the molecular size of these odor components is 1 nm or more, the use of porous particles having an average pore diameter of 2 nm or more as a deodorant can effectively adsorb a plurality of odor components. it can.

  The average pore diameter of the porous particles as the deodorant means the peak of the pore diameter in the pore diameter distribution. The peak of the pore diameter of the porous particles may be smaller than the size of the fragrance component from the viewpoint of the odor adsorption effect and the difficulty of adsorbing the fragrance component volatilized from the fragrance described above, making it difficult to alter and reduce the fragrance. Preferably, it is 0.1 μm or less, more preferably 0.04 μm or less, and preferably 0.005 μm or more. The peak of the pore diameter of the porous particles is measured by the following method.

<Measurement method of peak of pore diameter of porous particles>
The peak of the pore diameter of the porous particles can be measured by a multipoint method using liquid nitrogen using a pore distribution measuring device (Nippon Bell Co., Ltd., trade name: BELSORP mini II). The peak top in the pore distribution is defined as the pore diameter peak. The measurement sample is pretreated by heating at 110 ° C. for 1 hour.

  In addition, a water-soluble pH buffer as a deodorant is an agent that neutralizes acidic and alkaline odor components generated in a liquid phase such as excreta and reduces the change in pH. That is, it is a neutralizing deodorant by an equilibrium action. Such an agent is not particularly limited, and examples thereof include a weak acid and its conjugate base, or a mixture or salt thereof, and a weak base and its conjugate acid, or a mixture or salt thereof. Specific examples of the water-soluble pH buffering agent include citric acid and the like as a weak acid, and metal salts such as Na, K and Ca as a salt thereof. Examples of the weak base include polyhydroxyamine compounds such as tris (hydroxymethyl) aminomethane.

  Particularly preferred as a water-soluble pH buffer as a deodorant is one containing citric acid and tris (hydroxymethyl) aminomethane. By combining such weak acid and weak base components, not only odors derived from acidic and alkaline odor components, but also odors including neutral odors that could not be suppressed only by pH buffering deodorants. Production can be strongly suppressed. According to the napkin 1 provided with the absorbent body 4 containing such a preferable pH buffer, even when the wearing time is relatively long, an unpleasant odor derived from the excreted body fluid is almost noticed around the wearer. High deodorizing effect can be realized.

  Of the deodorants described above, the porous particles can carry an antibacterial or bactericidal metal. In that case, the porous particles have both properties of a deodorant and an antibacterial agent. The napkin 1 preferably includes porous particles carrying an antibacterial metal on the absorber 4 (particularly the central absorbent portion 43). In that case, the content of the porous particles carrying the antibacterial metal takes into account the content as both an antibacterial agent and a deodorant.

  As described above, when the central absorbent portion 43 (central absorbent sheet 402) contains a deodorant, it is preferable that at least the first region E contains a deodorant. More preferably, the odorant is a porous deodorant carrying an antibacterial metal.

  In the napkin 1, as shown in FIGS. 1 to 3, the absorbent body 4, more specifically the surface, is disposed on the excretory part facing part B including the excretion spot part that is disposed to face the excretion part of the wearer when worn. A slit 45 penetrating the laminated structure including the side absorbent sheet 41, the central absorbent portion 43, and the back side absorbent sheet 42 in the thickness direction is formed. The slit 45 is formed by cutting the absorber 4 (absorbent sheets 401 and 402), and has a shape that is long in one direction in plan view. In the illustrated example, each of the plurality of slits 45 has a linear shape extending in the longitudinal direction X in plan view. Thus, body fluid such as menstrual blood that has reached the absorber 4 is formed in the absorber 4 positioned at least in the excretory portion facing portion B by the slit 45 penetrating the absorber 4 in the thickness direction. However, it becomes easy to diffuse in the extending direction of the slit 45 (longitudinal direction X in the present embodiment), and also easily penetrates in the thickness direction of the absorbent body 4, thereby further improving the liquid absorption capacity of the absorbent body 4. Moreover, the dry feeling of the skin facing surface of the surface sheet 2 can be improved, which can lead to an improvement in wearing feeling.

  In the napkin 1, as shown in FIGS. 1 and 3, the plurality of slits 45 extending in the vertical direction X include not only the excretory part facing part B but also the part near the excretory part facing part B in the front part A and the rear. The slit region 45S is formed by being distributed over a portion of the portion C near the excretion portion facing portion B. The slit region 45S has a length in the vertical direction from the front end of the slit 45 located at the foremost position in the vertical direction X to the rear end of the slit 45 located at the rearmost position, and the slit region 45S This is a quadrangular range in plan view with the lateral length extending from the outer edge to the outer edge of the slit 45 located on the other side.

  In the napkin 1, as shown in FIG. 3, the slits 45, particularly the slit regions 45 </ b> S in which the slits 45 are dispersedly arranged, are the surface side absorbent sheet 41, the central absorbent portion 43, and the back side absorbent sheet. Since all of 42 overlaps with the laminated area, the slit 45 opens following the movement of the wearer's body when the napkin 1 is worn, and the central absorbent portion 43 (second area) in which the antibacterial agent is arranged F) Body fluid can be quickly induced. In addition, the slit 45 is a so-called “cut”, and is different from an “opening” formed by cutting off a part of the absorbent body (absorbent sheet) in plan view, so that the natural state of the absorbent body 4 (no external pressure is applied). ) Is not substantially open and is in a closed state, so that the antibacterial agent disposed in the central absorbent portion 43 (second region F) and the body fluid that has moved into the central absorbent portion 43 pass through the slit 45. Inconvenience of moving to the skin facing surface of the napkin 1 (skin facing surface of the top sheet 2) hardly occurs. Thus, the formation of the slit 45 is useful for improving the antibacterial effect and absorption performance of the napkin 1.

  In particular, in the napkin 1, as shown in FIG. 2, the width of the slit 45, that is, the length in the direction perpendicular to the extending direction of the slit 45 (longitudinal direction X in this embodiment) is the absorber 4 (the laminated structure). ) Gradually decreases from the non-skin facing surface side (back sheet 3 side) toward the skin facing surface side (top sheet 2 side). In the napkin 1, all of the plurality of slits 45 formed in the absorbent body 4 have a tapered shape from the non-skin facing surface side to the skin facing surface side. Thus, when the slit 45 in the absorbent body 4 has a tapered shape from the non-skin facing surface side toward the skin facing surface side, the width of the slit 45 is constant in the thickness direction of the absorbent body 4. Compared to the above, so-called liquid return, in which the bodily fluid once absorbed in the absorbent body 4 (central absorption portion 43) returns to the surface sheet 2 side due to body pressure at the time of wearing, etc., is effectively suppressed, and the liquid absorption capacity It can lead to improvement.

  The slit 45 has an opening width W45 (see FIG. 3) on the surface sheet 2 side of preferably 1.2 mm or less, more preferably 1.0 mm or less, and even more preferably 0.5 mm or less. The lower limit value of the opening width W45 is substantially 0 mm if the slit 45 is formed by cutting, but may be about 0.01 mm. Further, the distance D45 (see FIG. 3) between the slits 45 in the lateral direction Y is preferably 0.1 mm or more, more preferably 0.2 mm or more, and preferably 1.5 mm or less, more preferably 1. 2 mm or less. The opening width W45 of the slit 45 is measured by the following method.

<Measurement method of slit opening width>
The opening width of the slit formed in the absorbent body (absorbent sheet) is determined by taking the absorbent body to be measured out of the absorbent article, placing the absorbent body horizontally, and adjusting the measurement magnification with the KEYENCE digital microscope VHX-1000. And measured by magnifying.

  In addition, the length of the slit 45 (length in the extending direction of the slit 45) L45 (see FIG. 3) when the absorber 4 is viewed in plan is preferably 10 mm or more, more preferably 15 mm or more, and preferably It is 35 mm or less, more preferably 25 mm or less.

  In order to form the slit 45 in the absorber 4, the absorber 4 (laminated body of the absorbent sheets 401 and 402) may be partially cut by a known cutting means. As such a cutting device, for example, a cutting blade extending in the circumferential direction on the circumferential surface of the roll is dispersed in the circumferential direction and the axial direction of the roll, and the cutter roll receives the blade of the cutter roll. A cutting device provided with an anvil roll can be illustrated. As described above, when the slit 45 having a tapered shape is formed from the non-skin facing surface side toward the skin facing surface side, a cutting blade having an outer shape corresponding to such a shape may be used.

  In the present invention, the laminated structure of the central absorbent portion 43 (central absorbent sheet 402) is not limited to the form shown in FIG. 4, and various laminated structures can be adopted. The laminated structure of the central absorbent sheet may be in the form shown in FIGS. 6 (a) and 6 (b), for example. 6 (a) and 6 (b), the components different from those of the above embodiment will be mainly described, and the same components are denoted by the same reference numerals and the description thereof will be omitted. The description of the above embodiment is applied as appropriate to components that are not particularly described.

The laminated structure of the central absorbent portion 43 shown in FIG. 6A is formed by folding a single central absorbent sheet 402 along a bent portion b1 along the longitudinal direction X of the absorbent article.
In the central absorbent portion 43 shown in FIG. 6 (b), one central absorbent sheet 402 is folded along two folded portions b1 and b2 along the longitudinal direction X of the absorbent article and folded in a tri-fold state. It is formed with.
The laminated structure of the central absorbent portion 43 shown in FIG. 6C is formed by superposing two central absorbent sheets 402 and 402 so that the second regions F of the sheets 402 and 402 face each other. The sheets 402 and 402 are not bent.
In any of the central absorbent portions 43 shown in FIGS. 6A to 6C, the second region facing portion 2F is formed in which the second regions F face each other without the first region E interposed therebetween. .

As mentioned above, although this invention was demonstrated based on the preferable embodiment, the absorbent article of this invention is not restrict | limited to the said embodiment at all, and can be changed suitably.
For example, the absorbent article of the present invention may not have any one or both of the above-described longitudinal pressing grooves 92 and lateral pressing grooves 91 or all of the pressing grooves 9.
The absorbent article of the present invention may be a sanitary napkin as shown in the drawing, a panty liner (clay sheet), or the like.

1 Sanitary napkin (absorbent article)
2 Top sheet 3 Back sheet 4 Absorber 401 Main body absorbent sheet 41 Front side absorbent sheet 42 Back side absorbent sheet 402 Central absorbent sheet E 1st area F 2nd area 2F 2nd area facing part 43 Central absorbent part 43a Upper sheet 43b Lower sheet 43c Intermediate sheet 45 Slit

Claims (6)

A liquid-permeable surface sheet that forms a skin facing surface, a back sheet that forms a non-skin facing surface, and an absorbent body that includes an absorbent sheet that is located between both sheets and includes a fiber material. Comprising an absorbent article having a longitudinal direction corresponding to the wearer's front-rear direction and a transverse direction perpendicular thereto,
The absorbent body has a surface side absorbent sheet located on the skin facing surface side, a back surface side absorbent sheet located on the non-skin facing surface side, at least in the central part in the lateral direction of the absorbent body, and between these two sheets. Having a laminated structure including a central absorbent portion located at
The central absorbent portion has a laminated structure in which a central absorbent sheet is laminated in a plurality of layers, and the central absorbent portion is a unit of a super absorbent polymer than the front side absorbent sheet and the back side absorbent sheet. There is much content per area,
The central absorbent sheet has, in its thickness direction, a first region and a second region in which an antibacterial agent is arranged and the content of the superabsorbent polymer is greater than the first region,
The absorbent article in which the 2nd area | region opposing part in which the said 2nd area | region mutually opposes not via the said 1st area | region is formed inside the laminated structure of the said center absorbent sheet.   2. The absorbent article according to claim 1, wherein the antibacterial agent in the second region is hardly water-soluble or water-insoluble, or is disposed in a state in which it is difficult to move by water moving in the thickness direction in the second region. . A slit that penetrates the absorbent body in the thickness direction is formed in the excretory part facing part of the absorbent article, including an excretion spot part that is disposed to face the excretion part of the wearer when worn,
The absorbent article according to claim 1 or 2, wherein the width of the slit gradually decreases from the non-skin facing surface side of the absorbent body toward the skin facing surface side.   The absorptive article according to any one of claims 1 to 3, wherein a fragrance is arranged on the central absorbent sheet.   Each of the front surface side absorbent sheet and the back surface side absorbent sheet is in contact with the first region, and the first region is a sheet than the surface side adjacent to the central absorbent portion of both absorbent sheets. The absorbent article according to any one of claims 1 to 4, wherein the density of the fiber material is high.   The absorbent article according to any one of claims 1 to 5, wherein a porous deodorant carrying an antibacterial metal is disposed in the first region.

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