CN111801076B

CN111801076B - Absorbent article

Info

Publication number: CN111801076B
Application number: CN201980016694.9A
Authority: CN
Inventors: 奥田富美子; 木村真由美; 田中聪
Original assignee: Kao Corp
Current assignee: Kao Corp
Priority date: 2018-03-15
Filing date: 2019-03-14
Publication date: 2022-05-17
Anticipated expiration: 2039-03-14
Also published as: WO2019177076A1; CN111801076A

Abstract

The invention provides an absorbent article (1) which comprises a front sheet (2), a back sheet (3), and an absorbent body (4) disposed between the two sheets, and which has a longitudinal direction (X) and a transverse direction (Y). The absorbent body (4) comprises, as a component, absorbent sheets (401, 402) containing a fibrous material. The absorbent body (4) has a laminated structure including a front side absorbent sheet (41) positioned on the skin-facing surface side, a back side absorbent sheet (42) positioned on the non-skin-facing surface side, and a central absorbent portion (43) positioned between the front side absorbent sheet and the back side absorbent sheet, at least in the central portion of the absorbent body (4) in the lateral direction Y. The central absorption section (43) has a first region (E) and a second region (F) in which the density of the fibrous material is higher than that of the first region (E) in the thickness direction thereof, and the antimicrobial agent (8) is disposed in the second region (F).

Description

Absorbent article

Technical Field

The present invention relates to an absorbent article.

Background

Absorbent articles such as sanitary napkins sometimes have problems such as unpleasant odor after absorption of body fluid such as menstrual blood, and itching due to contact of the wearer's skin with body fluid. In order to solve such problems, various studies have been made on the antibacterial function of absorbent articles. For example, patent document 1 describes an absorbent article having a functional absorbent body containing a functional material that provides at least an additional function such as an antibacterial function in a central portion of the absorbent article, and a wearer-side absorbent body that is provided closer to the wearer than the functional absorbent body and has a lower diffusion rate of body fluid than the functional absorbent body. Patent document 2 describes an absorbent article including an antimicrobial active sheet containing an antimicrobial agent, in which a low-density portion having a fiber amount of less than 50 mass% relative to the periphery is formed. Patent document 3 describes an absorbent article in which a functional material region containing a functional material containing an antibacterial agent and a fragrance is disposed between an absorbent layer containing an absorbent material that absorbs body fluid and a topsheet, and a pressed portion is formed by compressing the functional material region and an adjacent layer adjacent to the functional material region in the thickness direction.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2010-110443

Patent document 2: japanese patent laid-open publication No. 2014-158509

Patent document 3: japanese patent laid-open publication No. 2016-

Disclosure of Invention

The present invention is an absorbent article including a liquid-permeable front sheet forming a skin-facing surface, a back sheet forming a non-skin-facing surface, and an absorbent body located between the sheets and including an absorbent sheet containing a fibrous material as a constituent member, the absorbent article having a longitudinal direction corresponding to a front-back direction of a wearer and a transverse direction orthogonal to the longitudinal direction. The absorbent body 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 the front side absorbent sheet and the back side absorbent sheet, at least in the transverse direction of the absorbent body. The central absorption section has a first region and a second region in which the density of the fiber material is higher than that of the first region in the thickness direction thereof, and the antimicrobial agent is disposed in the second region.

Drawings

Fig. 1 is a plan view of a sanitary napkin which is a preferred embodiment of the absorbent article of the present invention.

Fig. 2 is a plan view showing the skin-facing side (topsheet side) of the absorbent body of the sanitary napkin shown in fig. 1.

Fig. 3 is a sectional view schematically showing a section taken along line III-III of fig. 1.

Fig. 4 (a) is a cross-sectional view of the central absorbent portion of the absorbent body of the sanitary napkin shown in fig. 1, and fig. 4 (b) is the same cross-sectional view showing the second region laminated portion of the central absorbent portion of the absorbent body as a black-filled portion. Fig. 4 (a) and fig. 4 (b) are also collectively referred to as fig. 4.

Fig. 5 is an enlarged cross-sectional view showing a cross-sectional structure in the thickness direction of an absorbent sheet constituting the absorbent body shown in fig. 4.

Fig. 6 (a) to (d) are cross-sectional views in the transverse direction and the thickness direction of an absorbent article showing another example of the lamination mode of the central absorbent sheet of the central absorbent portion.

Detailed Description

Although the absorbent articles described in patent documents 1 to 3 are provided with an antibacterial function, when a large amount of body fluid is excreted or when the absorbent articles are used for a long time, it is difficult to continuously suppress the growth of bacteria, and there is a concern that skin problems such as the generation of malodor and itching may occur.

Accordingly, an object of the present invention is to provide an absorbent article which can eliminate the drawbacks of the above-described conventional art.

Hereinafter, the absorbent article of the present invention will be described based on preferred embodiments thereof.

As shown in fig. 1 and 3, a sanitary napkin 1 (hereinafter, also referred to as a sanitary napkin 1) as one embodiment of the present invention includes a liquid-permeable topsheet 2 forming a skin-facing surface, a backsheet 3 forming a non-skin-facing surface, and a liquid-retentive absorbent body 4 disposed between the two sheets 2, 3. The front sheet 2, the absorber 4, and the back sheet 3 are integrated to form an absorbent body 5. Side leakage-preventing sheets 6 are disposed on the front sheet 2 side of both longitudinal side portions of the absorbent body 5.

The side leakage-preventing sheet 6 has a free end 6a not joined to the topsheet 2 and a fixed end 6b joined to the topsheet 2 as an inner end of the joining line 61, and when in use, a leakage-preventing pocket P for preventing lateral leakage is formed between the fixed end 6b and the free end 6a by being separated from the topsheet 2. A body adhering portion (not shown) for fixing to the crotch portion of the pants is provided on the surface of the absorbent body 5 other than the skin-facing surface. The sanitary napkin 1 further has a pair of flaps 7 extending laterally outward from the side edges of the absorbent main body 5 on both side portions in the longitudinal direction X. A flap part adhesive part (not shown) for fixing to a non-skin-facing surface of the crotch part of the pants is provided on the back sheet 3 side of the pair of flap parts 7.

The front sheet 2, the back sheet 3, and the side leakage preventing sheets 6 may be any of various sheets conventionally used in absorbent articles such as sanitary napkins without any particular limitation. For example, a single-layer or multi-layer nonwoven fabric, an apertured film, or the like can be used as the front sheet 2. The top sheet 2 may have irregularities 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, concave and convex portions having the above-described concave and convex shapes are used as the topsheet 2, the concave and convex portions having a first fiber layer positioned on the side closer to the skin of the wearer and a second fiber layer positioned on the side farther from the skin of the wearer, the fiber layers being integrated in the thickness direction by a plurality of locally formed joined portions, and the portions of the first fiber layer positioned between the plurality of joined portions being raised in a convex manner. As the uneven portion having a solid structure, for example, the uneven portion described in japanese patent laid-open nos. 2007 and 182662 and 2002 and 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 may be a liquid-impermeable (including liquid-impermeable) or water-repellent sheet, and a moisture-permeable resin film or the like is preferably used. As the side barrier sheet 6, a laminated nonwoven fabric having high water pressure resistance, a laminated body of a resin film and a nonwoven fabric, or the like can be used.

As shown in fig. 1, the sanitary napkin 1 has a discharge portion facing portion B including a discharge position portion disposed to face a liquid discharge portion of a wearer when worn, a front portion a disposed closer to the abdomen side (front side) of the wearer than the discharge portion facing portion B, and a rear portion C disposed closer to the back side (rear side) of the wearer than the discharge portion facing portion B.

The sanitary napkin 1 and the absorbent main body 5 have a longitudinal direction X corresponding to the front-rear direction of the wearer and a transverse direction Y orthogonal to the longitudinal direction X. That is, the sanitary napkin 1 and the absorbent main body 5 are divided into a front portion a, a discharge portion facing portion B, and a rear portion C in this order in the longitudinal direction X. In the following description, unless otherwise specified, the longitudinal direction X is a direction along the longitudinal direction X of the absorbent article or components thereof, and the lateral direction Y is a direction along the lateral direction Y of the absorbent article or components thereof. The components of the absorbent article also include a portion of the absorbent article including a plurality of components, such as the absorbent main body and the central absorbent portion described below.

In the absorbent article of the present invention, the skin-facing surface is a surface of the absorbent article or a component thereof which faces the skin side of the wearer when the absorbent article is worn, and the non-skin-facing surface is a surface of the absorbent article or a component thereof which faces the side opposite to the skin side (usually, the clothing side) when the absorbent article is worn. In the absorbent article of the present invention, the excretion portion-corresponding portion B refers to a region having the wing portions in the longitudinal direction X of the absorbent article (a region sandwiched between the root portion of one wing portion in the longitudinal direction X and the root portion of the other wing portion in the longitudinal direction X), when the wing portions 7 are provided as in the sanitary napkin 1 of the present embodiment. In addition, when the absorbent article does not have the wing portions, the central region in the case where the entire length of the absorbent article in the longitudinal direction X is divided into three equal parts and the three 3 regions is generally the excretion portion-facing portion B.

In the sanitary napkin 1, the front sheet 2 covers the entire skin-facing surface side of the absorbent member 4, and the back sheet 3 covers the entire non-skin-facing surface side of the absorbent member 4. The extending portions of the front sheet 2 and the back sheet 3 extending from both end edges in the longitudinal direction X of the absorbent body 4 are joined to each other. Further, the back sheet 3 and the side leakage preventive sheet 6 are joined to each other at portions extending outward in the lateral direction Y from both side edges of the absorbent body 4 in the longitudinal direction X. In this way, the absorbent body 4 is sandwiched between the front sheet 2 and the back sheet 3, and the front sheet 2 or the side leakage preventing sheet 6 and the back sheet 3 are joined to each other over the entire periphery of the outer edge portion of the sanitary napkin 1. The sheets constituting the sanitary napkin 1 may be joined by any joining means such as an adhesive, heat sealing, ultrasonic sealing, or the like. In the example shown in fig. 1, the pair of side leakage-preventing

sheets

6 and 6 are joined to the topsheet 2 at a curved first join line 61 located at the excretory part B and a zigzag linear second join line 62 located in front of and behind the first join line 61 in the longitudinal direction X, respectively, but the side leakage-preventing sheets 6 and the topsheet 2 may be joined at a linear join line that continues over the entire length of the absorbent body 4.

In the sanitary napkin 1, as shown in fig. 3, a second sheet 21 made of nonwoven fabric is disposed between the topsheet 2 and the absorbent member 4. The second sheet 21 is preferably shorter in width (length in the lateral direction Y) than the width (length in the lateral direction Y) of the absorbent body 4, longer in the longitudinal direction X than the length in the longitudinal direction X of the absorbent body 4, and disposed over the entire length in the longitudinal direction X of the sanitary napkin. The second sheet 21 is a sheet that is also called a sub-sheet in the art and is separate from the topsheet 2 and the absorbent body 4, and is partially joined to the topsheet 2 and/or the absorbent body 4 by an adhesive or the like provided in a stripe or spiral shape. The second sheet 21 is a sheet that functions to improve the permeability of liquid from the topsheet 2 to the absorbent body 4, or to reduce the rewet of liquid absorbed into the absorbent body 4 to the topsheet 2.

The menstrual blood absorbent article of the present invention may not have the second sheet.

As shown in fig. 3, the absorbent body 4 includes

absorbent sheets

401 and 402 containing a fibrous material as constituent members, and in the present embodiment, has a laminated structure in which a plurality of absorbent sheets are laminated. More specifically, the excretion portion-facing portion B has a laminated structure including a front side absorbent sheet 41 positioned on the skin-facing surface side, a back side absorbent sheet 42 positioned on the non-skin-facing surface side, and a central absorbent portion 43 positioned between these sheets, at least in the central portion in the lateral direction Y of the absorbent body 4.

As shown in fig. 2, the central absorbent portion 43 of the sanitary napkin 1 is disposed only in the central portion in the transverse direction Y of the absorbent body 4 at the excretion portion-corresponding portion B, but the central absorbent portion 43 of the present invention may be disposed between the front side absorbent sheet 41 and the back side absorbent sheet 42 in the thickness direction Z of the absorbent body 4, and may have a width extending over the entire width (total width) of the absorbent body 4. Further, the central absorbent portion 43 of the sanitary napkin 1 is disposed only in a part in the longitudinal direction of the absorbent body 4 as shown in fig. 2, but the central absorbent portion 43 of the present invention may have a length extending over the entire length in the longitudinal direction of the absorbent body 4. In fig. 2,

reference numerals

43s and 43s denote positions of both end edges of the central absorption portion 43 in the width direction.

As shown in fig. 3 and 4 (a), the central absorbent portion 43 of the present embodiment has a structure in which central absorbent sheets 402 are stacked in multiple layers. The central absorbent portion 43 may have a single-layer structure in which the central absorbent sheets 402 are not laminated.

As shown in fig. 3 and 4 (a), the central absorbent portion 43 of the sanitary napkin 1 has a structure in which the central absorbent sheets 402 are stacked in multiple layers by folding one central absorbent sheet 402. The central absorbent sheet 402 of the central absorbent portion 43 is folded and folded at 2 folded portions b1 and b2 spaced apart in the transverse direction Y of the absorbent body 4 to form a 3-layer laminated structure. More specifically, the central absorbent sheet 402 is folded into a spiral shape as a whole by being folded toward the back sheet 3 at the 1 st fold portion b1 from one end edge e1 of the central absorbent sheet 402 in the longitudinal direction X, and being folded toward the front sheet 2 so that the other end edge e2 opposite to the one end edge e1 is disposed inside the 3-layer layered structure at the 2 nd fold portion b2 from the one end edge e 1.

By folding the central absorbent sheet 402 in this manner, an upper sheet 43a located on the skin-facing surface side of the laminate structure of the central absorbent sheet 402, i.e., the front sheet 2 side, a lower sheet 43b located on the back sheet 3 side, i.e., the non-skin-facing surface side of the laminate structure, and an intermediate sheet 43c located between these two

sheets

43a, 43b are formed. In the central absorbent portion 43 shown in fig. 4, the upper side S1 is directed toward the skin-facing surface, i.e., the topsheet 2 side, and the lower side S2 is directed toward the backsheet 3, i.e., the non-skin-facing surface.

On the other hand, the front side absorbent sheet 41 is disposed on the skin-facing surface side of the central absorbent portion 43 and covers the entire skin-facing surface side of the central absorbent portion 43, and the back side absorbent sheet 42 is disposed on the non-skin-facing surface side of the central absorbent portion 43 and covers the entire non-skin-facing surface side of the central absorbent portion 43. The front side absorbent sheet 41 and the back side absorbent sheet 42 may be separate sheets, and in the present embodiment, the center portion in the width direction of one wide main body absorbent sheet 401 constitutes the front side absorbent sheet 41, and the portion of the main body absorbent sheet 401 on the non-skin-facing side of the absorbent body 4 constitutes the back side absorbent sheet 42. In the example shown in fig. 3, the main absorbent sheet 401 is folded toward the non-skin-facing surface side at both ends in the transverse direction of the absorbent body 4, and the distal ends of the portions extending inward in the transverse direction of the absorbent body 4 from the folded portions are laminated.

As shown in fig. 5, the central absorbent sheet 402 constituting the central absorbent portion 43 has a first region E and a second region F in which the density of the fibrous material 48 is higher than that of the first region E in the sheet thickness direction. 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 the interface between the first region E and the second region F may be unclear by making one fiber material 48 enter the space between fibers of the other fiber material 48 at the boundary between the two regions.

The main absorbent sheet 401 in the sanitary napkin 1 of the present embodiment has the same configuration as the central absorbent sheet 402, except that the first region E and the second region F do not contain an antimicrobial agent.

Examples of the fibrous material 48 included in the central absorbent sheet 402 and the main absorbent sheet 401 include a fibrous material obtained by hydrophilizing hydrophobic fibers and hydrophilic fibers that are hydrophilic in nature. Particularly preferred is a fibrous material which is hydrophilic in nature and has water-retention properties. Preferred examples of the hydrophilic fiber include natural fibers, cellulose-based regenerated fibers, and semi-synthetic fibers. Examples of the hydrophilic fiber having water retentivity include cellulose fibers such as wood pulp fibers, rayon fibers, cotton fibers, and cellulose acetate fibers. The cellulose fiber can be used alone 1 or a combination of 2 or more. As the raw material pulp of the cellulose-based fiber, there can be mentioned: wood pulp such as softwood kraft pulp or hardwood kraft pulp, and non-wood pulp such as cotton pulp or straw pulp. As the cellulose-based fibers, crosslinked cellulose fibers (pulp fibers) obtained by crosslinking cellulose intramolecularly or intermolecularly with an appropriate crosslinking agent, regenerated cellulose fibers such as rayon fibers having improved crystallinity of cellulose, and the like can also be used.

The central absorbent sheet 402 and the main absorbent sheet 401 may contain both cellulose-based fibers and synthetic fibers such as thermoplastic fibers, or may contain synthetic fibers such as thermoplastic fibers instead of cellulose-based fibers. As thermoplastic fibers, for example, also: a single fiber formed using a single synthetic resin such as polyethylene, polypropylene, polyester, or polyurethane, or a composite fiber formed using a synthetic resin such as a composite of 2 or more of these, for example, a core-sheath type or side-by-side type composite fiber formed using 2 or more of synthetic resins.

As shown in fig. 1, in the sanitary napkin 1, the central absorbent sheet 402 is arranged from the excretion portion-facing portion B to a part of the rear portion C in the longitudinal direction. Therefore, the portion where the central absorbent sheet 402 is disposed becomes the large thickness portion 47 where the thickness of the absorbent body 4 is larger than the periphery thereof. Therefore, the absorbent body 4 is easily brought into close contact with the skin of the wearer when worn in the portion where the central absorbent sheet 402 is disposed.

As a configuration for providing the second region F having a higher density than the first region E, each of the central absorbent sheet 402 and the main absorbent sheet 401 includes, for example: the second region F may be provided over the entire region overlapping the first region E in the thickness direction, or may be provided locally so as to overlap only part of the first region E in the thickness direction. In the sanitary napkin 1 of the present embodiment, both the central absorbent sheet 402 and the main absorbent sheet 401 are provided with the second region F over the entire region overlapping the first region E in the thickness direction.

Whether or not the absorbent sheet has the first region E and the second region F in which the densities of the fibrous materials are different from each other can be determined, for example, by the following method.

[ method for measuring Density of fiber Material ]

The cross section of the absorbent sheet (nonwoven fabric) or the absorber in the thickness direction is observed under magnification using a microscope (for example, "VHX-1000" manufactured by KEYENCE corporation) or a scanning electron microscope (for example, JCM-5100 manufactured by japan electronics corporation), and image data of the cross section is acquired. The magnification in observation is a magnification at which about 10 to 70 fiber cross sections can be observed, and is usually 20 to 200 times. In the observation field of the cut surface, the area per fixed field of view (0.02 mm) was measured by image analysis²) The area occupied by the fibers. Specifically, the obtained image is subjected to binarization by setting a threshold value at a luminance boundary between a fiber and a portion where no fiber is present, using image processing software such as ImageJ. In general, when binarization is performed with white and black, since the fibers are white and the portion where no fibers are present is black, a region with a large number of white portions can be recognized as the second region F and a region with a large number of black portions can be recognized as the first region E in the thickness direction of the absorbent sheet. Then, the above-mentioned fixed visual field areas (0.02 mm) were calculated respectively²) The area having white and the area having black in the interior are converted into an area per unit area (1 mm)²) The area of the fiber(s) is set to the density (mm) of the fiber material²/mm²). The density of the fibrous material was measured at any 3 points in each of the first region E and the second region F of the absorbent sheet, and the average value thereof was defined as the fiber density of the sample.

In the central absorbent sheet 402, the density of the fibrous material in the second region F measured by the above method 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, and further preferably 1.2 times or more and 10 times or less, more preferably 2 times or more and 7 times or less, with respect to the density of the fibrous material in the first region E measured by the same method.

The absorbent sheet is an absorbent body formed into a sheet shape, and is generally distinguished from an absorbent body having a structure obtained by stacking an absorbent material. Representative examples of the absorbent sheet include an absorbent sheet described in japanese patent No. 2963647, an absorbent sheet described in japanese patent No. 2955223, and the like. As the absorbent sheet, an absorbent sheet in which constituent fibers are bonded to each other or a sheet-like shape is formed by bonding the superabsorbent polymer and the constituent fibers with an adhesive force of the superabsorbent polymer in a wet state or an adhesive such as an adhesive or adhesive fibers added thereto can be preferably used. As the absorbent sheet, there can be used: an absorbent sheet containing pulp, which is produced by the method described in japanese patent application laid-open No. 8-246395; a dry sheet in which pulverized pulp supplied with an air flow and a super absorbent polymer are stacked and then fixed with an adhesive (for example, a vinyl acetate adhesive, PVA, or the like); an absorbent sheet obtained by spreading a super absorbent polymer after applying a hot melt adhesive or the like between paper or nonwoven fabric containing pulp; an absorbent sheet obtained by blending a super absorbent polymer in a spun bond or melt blown nonwoven fabric production process. These absorbent sheets can be used as a sheet-like absorbent body by cutting one sheet into a predetermined shape.

As described above, the central absorbent portion 43 of the absorbent body 4 in the sanitary napkin 1 has a structure in which the central absorbent sheet 402 is laminated in 3 layers, and thus the first region E having a relatively low density of fibrous material and the second region F having a relatively high density of fibrous material are oriented from the skin-facing surface side to the non-skin-facing surface side in the thickness direction Z of the central absorbent portion 43, and the first region E, the second region F, and the first region E are formed in this order. The black-filled portion in fig. 4 (b) is a second region laminated portion 44 in which the second regions F having a relatively high density of the fiber material are directly laminated without interposing the first region E therebetween. The second region laminated portion 44 of the central absorbent portion 43 shown in fig. 4 (a) and 4 (b) is composed of the second region F of the intermediate sheet 43c and the second region F of the lower sheet 43 b.

In the absorbent body 4 of the sanitary napkin 1, the antimicrobial agent 8 is disposed in the second region F of the central absorbent sheet 402 constituting the central absorbent portion 43. More specifically, the antibacterial agent 8 is disposed in the second region F of the entire region of the central absorbent sheet 402 in the direction parallel to the sheet surface. Therefore, the antibacterial agent 8 is disposed in the second region F of the upper sheet 43a, the second region F of the intermediate sheet 43c, and the second region F of the lower sheet 43b, and the antibacterial agent 8 is disposed in two of the 2 second regions F constituting the second region laminated portion 44, that is, in the second region F of the intermediate sheet 43c and in the second region F of the lower sheet 43 b.

The sanitary napkin 1 of the present embodiment is used by being fixed to the crotch portion of shorts, as in a normal sanitary napkin.

According to the sanitary napkin 1 of the present embodiment, since the excretion portion-facing portion B has the central absorbent portion 43 at least in the central portion in the lateral direction Y of the absorbent body 4, the absorbent body 4 is in close contact with the excretion portion of the wearer, and the body fluid supplied from the skin-facing surface side is rapidly absorbed into the central absorbent portion 43 during wearing of the sanitary napkin 1. The central absorbent sheet 402 constituting the central absorbent portion 43 is positioned at the excretion portion-facing portion B, and has a first region E in which the density of the fibrous material is relatively low and a second region F in which the density of the fibrous material is relatively high, and the bodily fluid is easily guided and held in the second region F. Further, since the central absorbent portion has the front side absorbent sheet 41 on the skin-facing surface side thereof, the body fluid introduced into the central absorbent portion is less likely to return to the skin of the wearer. Since the antimicrobial agent 8 is disposed in the second region F, the body fluid absorbed into the central absorbent portion 43 can be stably brought into contact with the antimicrobial agent 8 for a long period of time immediately after being discharged in the second region F of the central absorbent sheet 402. Therefore, the antibacterial effect of the antibacterial agent can be effectively utilized.

Since the high antimicrobial effect is obtained by disposing the antimicrobial agent in the central absorbent portion 43, the antimicrobial agent may not be disposed over the entire absorbent body 4, for example. Therefore, even a relatively small amount of the antibacterial agent can obtain an excellent antibacterial effect, and generation of malodor caused by bacteria and generation of other problems caused by bacteria can be suppressed efficiently and for a long time. In particular, if the absorbent body 4 is manufactured without applying the antimicrobial agent to the front side absorbent sheet 41, the antimicrobial agent is less likely to migrate to the skin of the wearer, and therefore the antimicrobial agent is less likely to come into contact with indigenous bacteria present in the skin of the wearer, and the feeling of use is improved.

In the sanitary napkin 1 of the present embodiment, as described above, the central absorbent portion 43 has the second zone-laminated portion 44, and the antimicrobial agent 8 is disposed in the second zone F constituting the second zone-laminated portion 44. Since the second zone laminate 44 is a portion where the second zones F of high density of fibrous material overlap, the amount of the antimicrobial agent 8 per unit area of the second zone laminate 44 is greater than that of the portion other than the second zone laminate 44, and the probability of the body fluid coming into contact with the antimicrobial agent immediately after excretion is increased. Further, since the antimicrobial agent is provided in the region surrounded by the region where the fiber material has a high density and a high liquid retention property, the body fluid and the antimicrobial agent 8 are less likely to move from the second region laminated part 44 even after the body fluid is absorbed. Therefore, the frequency of contact between the body fluid in the second region laminated portion 44 and the antimicrobial agent 8 can be easily maintained high, and the antimicrobial effect can be maintained well. Therefore, for example, the following effects can be obtained: (1) the antibacterial effect can be exhibited for a long time even with a small amount of the antibacterial agent; (2) reduction of target species that are not likely to produce antibacterial effects; (3) the effect of suppressing the generation of unpleasant odor is maintained for a long period of time.

The above-described effects can be exhibited even when the antibacterial agent is disposed in only one of the 2 second regions F constituting the second region laminated portion 44, but more preferably, the antibacterial agent 8 is disposed in both of the 2 second regions F constituting the second region laminated portion 44 as in the sanitary napkin 1 of the present embodiment. In addition, in terms of the persistence of the antibacterial effect, it is preferable that the antibacterial agent is disposed in at least the second region F on the skin-facing surface side among the 2 second regions F constituting the second region laminated portion 44.

In the sanitary napkin 1 of the present embodiment, the antimicrobial agent 8 is disposed over the entire second region-laminated portion 44 in a plan view of the absorbent body 4.

If the antimicrobial agent 8 is disposed over the entire area of the second region laminated portion 44 in the plan view of the absorbent body 4, the area of contact with the antimicrobial agent 8 increases even after the body fluid has been spread in the sanitary napkin 1 after the body fluid has been repeatedly discharged, and the body fluid can be brought into contact with the antimicrobial agent 8 over a wider range. By bringing the body fluid into contact with the antibacterial agent in a wider range, an excellent effect of exerting an antibacterial effect on a larger amount of body fluid can be obtained.

From the viewpoint of increasing the contact area with the body fluid and enhancing the antibacterial effect, it is preferable that the antibacterial agent 8 be distributed over the entire second region F in the direction parallel to the surface of the central absorbent sheet 402. The gram weight of the antimicrobial agent 8 can be appropriately determined depending on the type of the antimicrobial agent, and is preferably 0.005g/m²Above, more preferably 0.03g/m²Above, and preferably 5.0g/m²Hereinafter, more preferably 3.0g/m²Hereinafter, it is preferably 0.005g/m²Above and 5.0g/m²Hereinafter, more preferably 0.03g/m²Above and 3.0g/m²The following.

As the antibacterial agent 8 used in the present invention, those used for antibacterial purposes in absorbent articles such as sanitary napkins can be used without particular limitation. Examples thereof include antibacterial metals, antibacterial metal carriers, organic antibacterial agents and the like.

Examples of the metal having antibacterial properties include: copper, silver, gold, lead, nickel, tin, zinc, iron, zirconium, and the like.

Examples of the antibacterial metal support include: a water-insoluble or water-insoluble antibacterial agent such as silver zeolite, a divinylbenzene-2-vinylpyridine silver copolymer (described in, for example, japanese patent application laid-open No. 2006-307404), an aluminum/silver/sodium nitrate silicate (described in, for example, japanese patent application laid-open No. 2005-232654), a silica/zinc oxide/alumina composite carrying silver or zinc (specifically, a metal-substituted cancrinite-like mineral carrying an antibacterial metal), silver zirconium phosphate, and a silver/zinc zeolite mixture.

The organic antibacterial agent is preferably a quaternary ammonium salt, and among them, the following are appropriately listed: benzalkonium chloride, cetylphosphorylated benzalkonium chloride, and the like, which are poorly water soluble.

The sanitary napkin 1 preferably contains a water-insoluble or poorly water-soluble antibacterial agent as the antibacterial agent. When an antibacterial agent that is poorly water-soluble or water-insoluble as described below is used as the antibacterial agent, migration of the antibacterial agent to other sites can be suppressed, and therefore, the persistence of the antibacterial effect is further improved by maintaining the concentration of the antibacterial agent in the second region F or the second region laminated portion 44, or the like. As an example of the sparingly water-soluble or water-insoluble antibacterial agent, the antibacterial metal support is preferred. The antibacterial metal carrier is water-insoluble or water-insoluble, and means that the carrier (preferably porous particles) carrying the antibacterial metal is water-insoluble or water-insoluble even if the metal to be carried is water-soluble.

In the present invention, the antimicrobial agent 8 is incorporated into the second region F of the central absorbent sheet 402, in which the density of the fibrous material is relatively high, so that the bodily fluid can be easily retained in the second region F. Therefore, since the antibacterial agent 8 can be inhibited from moving from the second region F to other components, a water-soluble antibacterial agent can also be used. In particular, when the antimicrobial agent 8 is mixed in the second zone F constituting the second zone stack portion 44, the antimicrobial agent can be more effectively inhibited from moving from the second zone F to another member.

Here, the term "sparingly water-soluble" means that the solubility of the antibacterial agent in ion-exchanged water at 25 ℃ is less than 20g per 100g of ion-exchanged water, and the solubility of the sparingly water-soluble antibacterial agent in ion-exchanged water at 25 ℃ is preferably 10g or less, more preferably 1g or less. In the present specification, the water-insoluble matter is defined as water-insoluble matter when the solubility is 0.1g or less. In the present specification, the term "sparingly water-soluble" and "water-insoluble" may be collectively referred to as "sparingly water-soluble" in a generic sense. On the other hand, the term "water-soluble" as used herein means that the water-soluble antibacterial agent has a solubility in ion-exchanged water at 25 ℃ of 20g or more, and the solubility in ion-exchanged water at 25 ℃ of the water-soluble antibacterial agent is preferably 40g or more, more preferably 50g or more.

The solubility can be measured by the following method. 100g of ion-exchanged water at 25 ℃ in a 200mL beaker was charged with a sufficiently dried object to be measured (antibacterial agent), and the object was placed in a stirring piece having a length of 20mm and a width of 7mm, and stirred at 600rpm with a magnetic stirrer, and the amount of the object charged until the object was not dissolved even after stirring for 1 hour was defined as the solubility of the antibacterial agent in water at 25 ℃. As the magnetic stirrer, HPS-100 manufactured by AS ONE corporation, etc. can be used.

The content of the antimicrobial agent 8 is preferably 0.001 mass% or more, more preferably 0.01 mass% or more, and preferably 12 mass% or less, more preferably 5 mass% or less, and is preferably 0.001 mass% or more and 12 mass% or less, more preferably 0.01 mass% or more and 5 mass% or less, with respect to the total mass of the central absorbent sheet 402 constituting the central absorbent portion 43 of the absorbent body 4.

The absorbent article of the present invention preferably contains a deodorant in the absorbent body 4, and particularly preferably contains a deodorant in the central absorbent sheet 402 constituting the central absorbent portion 43. By incorporating a deodorant in the absorbent body 4 and/or the central absorbent sheet 402, generation of an unpleasant odor caused by bacteria can be more effectively suppressed by combination with an antibacterial agent.

In the case where the central absorbent sheet 402 contains a deodorant, the deodorant may be contained only in the first region E, may be contained only in the second region F, or may be contained in both of the first and second regions E, F, and preferably at least the second region F contains a deodorant. The antibacterial agent has an effect of suppressing the generation of odor caused by bacteria, etc., and the deodorant is expected to suppress odor not caused by bacteria or odor generated before the antibacterial agent acts. By the presence of the deodorant in the central absorbent portion 43, particularly in the second region F, it is possible to effectively suppress the escape of odor from the skin-facing surface side and the non-skin-facing surface side of the absorbent article.

The deodorant is a substance which itself directly acts on an odor (odorant), i.e., can exhibit a deodorizing effect by adsorbing, neutralizing, decomposing, etc. the odor (odorant), and can be used in a wide range of applications in the art. Examples of the deodorant used in the present invention include porous particles and a water-soluble pH buffer.

The porous particles as a deodorant are particles having a plurality of pores at least on the particle surface and capable of capturing, adsorbing and/or encapsulating a volatile odor component in the pores. The material of the porous particles may be an organic compound, an inorganic compound, a polymer thereof, or a combination thereof. Specific examples thereof include: synthetic porous polymers such as acrylic polymers including porous methacrylic polymers and porous acrylic polymers, aromatic polymers including porous divinylbenzene polymers and porous pyridine copolymers, and copolymers thereof; natural porous polymers such as chitin and chitosan; and metal-supporting porous materials such as inorganic porous materials including zinc oxide, activated carbon, silica (silica gel), calcium silicate, aluminosilicate compounds, high-silica zeolite (hydrophobic zeolite), sepiolite, cancrinite, zeolite, and hydrous zirconia, and preferably contains at least 1 selected from these. The odor component of the excretion liquid such as urine or menstrual blood to be deodorized is a mixture of various components such as ammonia, amines, fatty acids, hydrogen sulfide, thiols, and the like. In general, since the molecular size of these odor components is 1nm or more, a large number of odor components can be effectively adsorbed by using porous particles having an average pore diameter of 2nm or more as the deodorant.

The average pore diameter of the porous particles used in the present invention refers to the peak of the pore diameter of the pores in the pore diameter distribution. From the viewpoints of odor adsorption effect, difficulty in adsorption of fragrance components volatilized from the below-described perfumes, and difficulty in deterioration and reduction of fragrance, the peak of pore diameter of the porous particles is preferably smaller than the size of the fragrance components, preferably 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 was measured by the following method.

< method for measuring peak value of pore diameter of porous particle >

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 apparatus (product name: BELSORP mini II, manufactured by Nippon bel Co., Ltd.). The peak in the pore distribution was defined as the peak of the pore diameter. The measurement sample was subjected to pretreatment by heating at 110 ℃ for 1 hour.

The water-soluble pH buffer is a reagent for neutralizing acidic or alkaline odor components generated in a liquid phase such as an excretory fluid to reduce the change in pH. Namely, a neutralizing deodorant utilizing a balancing action. Such a reagent is not particularly limited, and examples thereof include a weak acid or a conjugate base thereof, or a mixture or salt thereof, a weak base or a conjugate acid thereof, or a mixture or salt thereof. Specific examples of the water-soluble pH buffer include weak acids such as citric acid, and salts thereof such as metal salts of Na, K, and Ca. Examples of the weak base include polyhydroxyamine compounds such as tris (hydroxymethyl) aminomethane.

In particular, in the sanitary napkin 1 of the present embodiment, citric acid and tris (hydroxymethyl) aminomethane are preferably contained as the pH buffer. By combining such a weak acid with a weak base component, it is possible to strongly suppress not only the generation of odor derived from acidic and basic odor components but also the generation of odor including odor in the vicinity of neutrality that cannot be suppressed by a deodorant having a pH buffering property alone. As a result, the absorbent article 1 using the absorbent body 4 containing the pH buffer can achieve a high deodorizing effect to the extent that the odor from the discharged liquid is hardly noticeable around the wearer even when worn for a long time.

In the deodorant, the porous particles can carry an antibacterial or bactericidal metal. In this case, the porous particles have both the properties of the deodorant and the antibacterial agent. In the sanitary napkin 1, the absorbent body preferably contains porous particles having an antibacterial metal supported thereon.

In the absorbent article of the present invention, the absorbent member 4 may contain a fragrance. The absorbent body 4 preferably contains a perfume in the central absorbent portion 43, that is, the central absorbent sheet 402, and more preferably contains a perfume in the second region F of the central absorbent portion 43 located inside in the thickness direction. In the manufacturing process of the absorbent body, the fragrance is preferably supplied from the second region F side of the central absorbent sheet 402. In this case, if the central absorbent sheet 402 is stacked so that the second regions face each other, excessive volatilization of the perfume into other portions can be suppressed, and the perfume is preferably maintained in a state where the central absorbent sheet is present at a high concentration until the start of use.

By disposing the fragrance in the central absorbent sheet 402 located inside in the thickness direction, excessive volatilization of the fragrance can be suppressed, and the persistence of the odor masking effect can be further improved. From the same viewpoint, it is preferable that the amount of the perfume is larger than that of the first region E in the second region F of the central absorbent sheet 402.

Examples of the perfume include: a spice, a plant extract, a citrus extract, and the like having a green herbal fragrance as described in Japanese patent laid-open No. 2007-244764.

The content of the perfume is not particularly limited, and may be appropriately set according to the kind of the perfume and the like. For example, the amount of perfume contained in the central absorbent sheet 402 in the developed state is preferably 0.1g/m²Above and 1g/m²Hereinafter, more preferably 0.2g/m²Above and 0.6g/m²The following.

The central absorbent sheet 402 and the main body absorbent sheet 401 preferably contain the super absorbent polymer 46, respectively, and the central absorbent sheet 402 and the main body absorbent sheet 401 having the first region and the second region each preferably contain the super absorbent polymer 46 in a larger amount in the first region E than in the second region F. In particular, when the water absorption rate of the super absorbent polymer disposed in the first region is 20mL/0.3g · 30 seconds or less, further 15mL/0.3g · 30 seconds or less, further 10mL/0.3g · 30 seconds or less, most or all of the excreted body fluid is preferably absorbed and held by the super absorbent polymer 46 in the first region E before being absorbed and held in the first region E and after being brought into contact with the antibacterial agent in the second region. The lower limit of the water absorption rate may be 0mL/0.3g · 30 seconds or more, and 2mL/0.3g · 30 seconds or more, and further 4mL/0.3g · 30 seconds or more, the body fluid after contact with the antibacterial agent is easily absorbed and held by the first region E appropriately, and is preferable in terms of suppressing liquid leakage.

The water absorption rate of the super absorbent polymer was measured by the following method.

< method for measuring Water absorption Rate >

The water absorption rate (unit: mL/0.3 g.30 sec) obtained by the DW method was measured using a commonly known apparatus (Demand Wettability Tester) as an apparatus for carrying out the DW method. Specifically, in this apparatus, the liquid level of the physiological saline was set to a water level equal to the surface of the polymer spreading table [70 mm. phi., the table on which No.2 filter paper was placed on the glass filter No.1 ], and 0.3g of the super absorbent polymer as the measurement object was spread on the surface of the polymer spreading table. The water absorption capacity at the time point of spreading the super absorbent polymer was set to 0, and the water absorption capacity after 30 seconds was measured. The water absorption amount is measured on a scale of a burette indicating the decrease amount of the water level of the physiological saline. The value of the water absorption capacity obtained was defined as the water absorption rate obtained by the DW method. The water absorption rate obtained by the DW method can be designed by the shape, particle diameter, bulk specific gravity, crosslinking degree, and the like of the super absorbent polymer. The measurement was carried out at 23. + -. 2 ℃ and 50. + -. 5% humidity, and the measurement was carried out after the sample was stored in the same environment for 24 hours or more before the measurement.

As the super absorbent polymer 46, a particulate super absorbent polymer is generally used, and a fibrous super absorbent polymer may be used. In the case of using a particulate super absorbent polymer, the shape thereof may be any of a spherical shape, a block shape, a bag shape, and an amorphous shape. As the super absorbent polymer, a polymer or copolymer of acrylic acid or an alkali metal salt of acrylic acid can be generally used. Examples thereof include polyacrylic acid and salts thereof and polymethacrylic acid and salts thereof. As the polyacrylate or polymethacrylate, a sodium salt can be preferably used. In addition, a copolymer obtained by copolymerizing a comonomer such as maleic acid, itaconic acid, acrylamide, 2-acrylamido-2-methylpropanesulfonic acid, 2- (meth) acryloylethanesulfonic acid, 2-hydroxyethyl (meth) acrylate, or styrenesulfonic acid with acrylic acid or methacrylic acid in a range that does not deteriorate the performance of the super absorbent polymer may also be used.

The thickness of each 1 absorbent sheet is preferably 0.1mm or more, particularly preferably 0.3mm or more, and preferably 2mm or less, particularly preferably 1.5mm or less. More specifically, the thickness of the absorbent article is preferably 0.1mm or more and 2mm or less, and particularly preferably 0.3mm or more and 1.5mm or less, in order to obtain an absorbent article having sufficient liquid diffusibility and liquid retentivity and having good wearing feeling.

The absorbent sheet having the first region and the second region used in the sanitary napkin 1 of the present embodiment can be produced, for example, by separately producing the first fiber sheet to be the first region and the second fiber sheet to be the second region by any method such as a wet papermaking method or a dry papermaking method, and then joining them together by an adhesive or binder fiber, the adhesive strength of a swollen super absorbent polymer, or the like. As a preferred example of the method for producing the absorbent sheet, a wet fibrous sheet is formed by a wet papermaking method, and the superabsorbent polymer is dispersed on the fibrous sheet to form a first wet fibrous sheet. Then, the second fibrous sheet in a dry state is superposed on the surface of the first fibrous sheet in a wet state on which the super absorbent polymer is dispersed to obtain a laminate sheet. Next, the laminate sheet is dried by a drying section using a Yankee dryer (Yankee dryer) or the like, and an intended absorbent sheet is obtained. The method of providing the fiber material with a density difference between the first fiber sheet and the second fiber sheet is not particularly limited, and examples thereof include: a method of making the pressure of the press section after papermaking in the second fiber sheet production step higher than that of the first fiber sheet; a method of forming the first fiber sheet to have a lower density than the second fiber sheet by making the material or thickness of the constituent fibers of the fiber sheets different; a method of arranging the second sheet on the Yankee dryer side in the drying section of the laminated sheet in which one or both of the first fiber sheet and the second fiber sheet are in a wet state, and drying the laminated sheet; or a combination of these 2 or more methods. The central absorbent sheet 402 used in the sanitary napkin 1 of the present embodiment can be produced by applying an antimicrobial agent in the production process of the second fibrous sheet to be the second region and then bonding and integrating the second fibrous sheet with the first fibrous sheet to be the first region. As a method of applying the antibacterial agent to the second fiber sheet side, there can be cited: a method of coating the second fiber sheet with a solution or dispersion containing an antibacterial agent before bonding; a method of applying a solution or dispersion containing an antibacterial agent to the second fiber sheet side surface of the composite sheet, and then heating or naturally drying the resultant; a method of spreading or blowing particles from a second fiber sheet side to a composite sheet. As a method for applying the solution or dispersion containing the antibacterial agent, there can be mentioned: a method using a known liquid coating apparatus such as spraying, transfer, die coating, gravure coating, ink jet method, screen printing, and the like.

The absorbent body 4 of the sanitary napkin 1 of the present embodiment has the large thickness portion 47, and the large thickness portion 47 includes 5 absorbent sheets in total, which are formed by sandwiching the central absorbent portion 43 formed of the central absorbent sheet 402 between the front side absorbent sheet 41 and the back side absorbent sheet 42. The large-thickness portion 47 is formed in the center portion of the absorbent body 4 in the lateral direction Y, and is mainly formed in the excretion portion-facing portion B in the longitudinal direction X of the absorbent body 4. The term "formed mainly in the drain facing portion B" means that 50% or more of the entire length of the large-thickness portion 47 in the longitudinal direction is present in the drain facing portion B. By providing the large-thickness portion 47 having a width smaller than the total width of the absorbent body 4 at the center portion in the width direction of the absorbent body 4, a large amount of body fluid discharged to the center portion in the width direction can be efficiently absorbed into the center absorbent portion 43, and the antimicrobial agent efficiently contacts the second region F in the center absorbent portion 43, so that generation of unpleasant odor due to bacteria can be more effectively suppressed. From this viewpoint, the width of the central absorbent portion 43 is preferably 25% or more, more preferably 40% or more, and preferably 75% or less, more preferably 60% or less, and further preferably 25% or more and 75% or less, more preferably 40% or more and 60% or less of the total width of the absorbent body 4 in the portion where the central absorbent portion 43 is present in the longitudinal direction X. From the same viewpoint, the length in the longitudinal direction X of the central absorbent portion 43 is preferably 5% or more, more preferably 15% or more, and preferably 65% or less, more preferably 55% or less, and further preferably 5% or more and 65% or less, more preferably 15% or more and 55% or less of the total length of the absorbent body 4 in the longitudinal direction X.

The thickness of the absorbent body 4 in the large thickness portion 47 is preferably 0.7mm or more, more preferably 1mm or more, and preferably 5mm or less, more preferably 4mm or less, more specifically preferably 0.7mm or more and 5mm or less, and more preferably 1mm or more and 4mm or less. By setting the thickness of the large thickness portion 47 in such a range, it is easy to achieve both good wearing feeling, high absorption performance, and high antibacterial effect in the excretion portion-corresponding portion B. In addition, in the case where the absorbent article has the wing portions as in the sanitary napkin 1 of the present embodiment, it becomes easy to suppress wrinkling of the absorbent body at the excretion portion-corresponding portion when worn. The thickness of the absorbent body in the portion other than the large-thickness portion 47 is preferably 0.3mm or more, more preferably 0.5mm or more, and preferably 3mm or less, more preferably 2.5mm or less, more specifically preferably 0.3mm or more and 3mm or less, and more preferably 0.5mm or more and 2.5mm or less. This range is preferable from the viewpoint of achieving high absorption performance and improving the following ability to the movement of the wearer. The thicknesses of the absorbent body and the absorbent sheet were measured by the following methods.

< method for measuring thickness of absorbent sheet and absorbent body >

The measurement was carried out at 5cN/cm by leaving the absorbent sheet or absorbent body as the object of measurement at a horizontal position without wrinkles or folds²Thickness under load. The thickness in the present invention was measured using a thickness meter PEACOCK DIAL UPRIGHT GAUGES R5-C (manufactured by OZAKI MFG. CO. LTD.). At this time, a plate (acrylic resin plate having a thickness of about 5 mm) having a circular or square shape in plan view (a plate having a thickness of about 5 cm) was disposed between the distal end portion of the thickness gauge and the measurement portion of the object to be measured, and the load was 5cN/cm²The size of the plate is adjusted.

In the sanitary napkin 1 of the present embodiment, as shown in fig. 2 and 3, the absorbent body 4 is provided with slits 45 extending parallel to the longitudinal direction X in the excretion portion-facing portion B of the absorbent body 4. Therefore, in the sanitary napkin 1 of the present embodiment, the longitudinal direction of the slit 45 is parallel to the longitudinal direction X. Through the slits 45, menstrual blood that has reached the absorbent body 4 becomes easy to spread in the longitudinal direction X, and also becomes easy to permeate in the thickness direction of the absorbent body 4. As shown in fig. 2, the sanitary napkin 1 has slits 45 extending in the longitudinal direction X, and slit regions 45S are formed in a state in which the slits 45 are distributed in both the longitudinal direction X and the transverse direction Y. The slit region 45S in which the plurality of slits 45 are arranged extends not only over the drain portion facing portion B but also over a part of the front portion a and a part of the rear portion C.

The slit 45 is formed by making an incision in the absorbent sheet.

If the slits 45, in particular, the slit regions 45S in which the slits 45 are arranged in a dispersed manner are arranged in a state of overlapping with the entire laminated region of the front side absorbent sheet 41, the center absorbent portion 43, and the back side absorbent sheet 42 of the absorbent body 4, the slits 45 open following the movement of the body of the wearer, quickly guide the body fluid to the center absorbent portion 43 to which the antibacterial agent is applied, and the antibacterial agent in the center absorbent portion 43 or the body fluid moved into the center absorbent portion 43 is not easily returned to the surface of the sanitary napkin 1 unlike the opening formed by cutting out a part of the absorbent sheet in a plan view. This provides excellent antibacterial effect and excellent absorption performance.

The slits 45 may be through-holes penetrating all the absorbent sheets from the front side absorbent sheet 41 to the back side absorbent sheet 42, or may be non-through-holes not penetrating all the absorbent sheets. The slit 45 preferably penetrates the front side absorbent sheet 41 and reaches the inside of the central absorbent portion 43 in the thickness direction. Examples thereof include, in addition to the slit 45 penetrating all the absorbent sheets, the following: a slit reaching the second region F of the upper sheet 43a of the central absorption portion but not reaching the first region E of the intermediate sheet 43 c; or a gap which reaches the second region of the middle sheet 43c of the central absorbent portion but does not reach the first region E of the lower sheet 43 b.

The slit 45 preferably has an opening width W45 on the front sheet 2 side of 1.2mm or less, more preferably 1.0mm or less, and further preferably 0.5mm or less. When the slit 45 is formed by a slit, the lower limit of the opening width W45 may be substantially 0mm, or may be about 0.01 mm. The distance D45 between the

slits

45, 45 in the lateral direction Y is preferably 0.1mm or more, more preferably 0.2mm or more, and preferably 1.5mm or less, more preferably 1.2mm or less, more specifically preferably 0.1mm or more and 1.5mm or less, and more preferably 0.2mm or more and 1.2mm or less. The opening width W45 of the slit 45 of the absorbent body 4 is measured by the following method.

< method for measuring opening width of slit 45 >

The opening width of the slit 45 was measured by taking out the absorbent member 4 from the sanitary napkin 1, horizontally placing the taken-out absorbent member 4, and adjusting and enlarging the measurement magnification by a digital microscope VHX-1000 manufactured by Keyence.

The length (length in the longitudinal direction) L45 (see fig. 2) of the slit 45 in a plan view of the absorbent body 4 is preferably 10mm or more, more preferably 15mm or more, and preferably 35mm or less, more preferably 25mm or less, and further preferably 10mm or more and 35mm or less, more preferably 15mm or more and 25mm or less.

In the sanitary napkin 1, adhesives are preferably applied and fixed between the front sheet 2 and the absorbent body 4 and between the absorbent body 4 and the back sheet 3. The layers of the stacked absorbent sheets constituting the absorbent body 4 may or may not be bonded to each other, and preferably are bonded to each other with an adhesive agent from the viewpoint of wrinkling or displacement of the absorbent body during use.

The adhesive can be applied by a known mechanism, for example, using a slit coating gun, a spiral spray gun, a spray gun, or a spot gun, and is preferably applied spirally to the sanitary napkin 1 using a spiral spray gun. As the adhesive to be applied, for example, a hot melt adhesive is preferably used. The coating amount of the hot-melt adhesive is preferably 1.5g/m²Above and 10g/m²The following.

In order to form the slits 45 in the absorbent member 4 as in the sanitary napkin 1, the stacked body of the absorbent sheets may be partially cut by a known cutting mechanism, and for example, a cutting device having a cutter roll in which a plurality of cutting blades extending in the circumferential direction are formed on the peripheral surface of a roll so as to be dispersed in the circumferential direction and the axial length direction of the roll, and a backup roll for receiving the blades of the cutter roll may be used.

As shown in fig. 1 and 3, the sanitary napkin 1 of the present embodiment has linear pressing grooves 9 on the skin-facing surface of the absorbent body 5, the front sheet 2 and the absorbent body 4 being integrally recessed toward the back sheet 3. The pressing grooves 9 are grooves in which both the topsheet 2 and the absorbent body 4 are concave, and the density of each fiber constituting the topsheet 2 and the absorbent body 4 is higher than that of the peripheral portion of the groove. The embossed grooves may be continuous lines or discontinuous lines such as broken lines, and may be formed of rows formed by discontinuous embossing of a plurality of points, for example. The sanitary napkin 1 has longitudinal compressed grooves 92 extending in the longitudinal direction X in both side portions of the excretory part facing portion B, and transverse compressed grooves 91 extending in the transverse direction Y in the front portion a and the rear portion C, respectively. It is preferable that the absorbent body 4 has the vertical compressed grooves 92 on both sides of the central absorbent portion 43 containing the antibacterial agent in the lateral direction Y in a plan view in order to suppress the spread of the body fluid in the lateral direction Y and prevent leakage, and to collect the body fluid in the central absorbent portion 43 containing the antibacterial agent. In addition, in a plan view of the absorbent body 4, it is preferable to provide the transverse compressed grooves 91 in the front and rear portions of the central absorbent portion 43 containing the antibacterial agent in the longitudinal direction X, in order to prevent leakage by suppressing diffusion of body fluid in the front and rear directions and to prevent wrinkles in the sanitary napkin. The absorbent article of the present invention may also be provided without either or both of the longitudinal compressed grooves 92 and the transverse compressed grooves 91 or all of the compressed grooves 9.

The present invention has been described above based on preferred embodiments thereof, but the sanitary absorbent article of the present invention is not limited to the sanitary napkin 1 of the above-described embodiments and can be modified as appropriate.

For example, either or both of the front side absorbent sheet 41 and the back side absorbent sheet 42 may not have the first region where the density of the fibrous material is relatively low and the second region where the density of the fibrous material is relatively high.

The lamination method of the central absorbent sheet of the central absorbent portion is not limited to the method shown in fig. 4, and various lamination methods can be employed.

The lamination method of the central absorbent sheet may be, for example, the method shown in fig. 6 (a) to 6 (d). The central absorbent portion 43 shown in fig. 6 (a) is formed by folding a central absorbent sheet 402 having a first region E and an antimicrobial-containing second region F in half along a fold portion b1 in the longitudinal direction of the absorbent article. The central absorbent portion 43 shown in fig. 6 (b) is formed by folding the central absorbent sheet 402 having the first region E and the second region F containing the antibacterial agent into a three-folded state along 2 folding portions b1, b2 in the longitudinal direction of the absorbent article. The central absorbent portion 43 shown in fig. 6 (c) is formed by overlapping 2 central absorbent sheets 402 each having a first region E and a second region F containing an antimicrobial agent, with the second regions F in surface contact with each other. In the central absorption portion 43 shown in fig. 6 (a) to 6 (c), the second region laminated portion 44 is formed in which the second regions F are directly laminated without interposing the first region E therebetween.

The central absorbent portion 43 shown in fig. 6 (d) is formed by laminating 2 central absorbent sheets 402 each having a first region E and an antimicrobial-containing second region F such that the second region F faces the non-skin-facing surface side. The description of the central absorbent portion 43 and the central absorbent sheet 402 of the sanitary napkin 1 of the above embodiment can be applied to the central absorbent portion 43 and the central absorbent sheet 402 shown in fig. 6 (a) to 6 (d) as appropriate, unless otherwise specifically contradicted. For example, in the central absorbent portion 43 shown in fig. 6 (a) to 6 (d), from the viewpoint of improving the persistence of the antibacterial effect of the antibacterial agent, it is preferable that the antibacterial agent is disposed in the second region F located inside the central absorbent portion 43 in the thickness direction Z, and in the central absorbent portion 43 shown in fig. 6 (a) to 6 (c), when the antibacterial agent is disposed in one or both of the 2 second regions F constituting the second region laminated portion 44, the antibacterial agent or the body fluid is less likely to move to other regions, and the concentration of the antibacterial agent or the persistence of the antibacterial effect is improved, which is preferable. In fig. 6 (a) to 6 (d), the upper side in the figure is the skin-facing surface side, and the lower side in the figure is the non-skin-facing surface, as in fig. 4.

The number of stacked central absorbent sheets 402 in the central absorbent portion 43 is preferably 2 or more, more preferably 3 or more, and preferably 7 or less, more preferably 5 or less, and is preferably 2 or more and 7 or less, more preferably 3 or more and 5 or less.

In the absorbent body 4, the total number of layers of the front side absorbent sheet 41, the back side absorbent sheet 42, and the central absorbent sheet 402 constituting the central absorbent portion 43 is preferably 3 or more, more preferably 5 or more, and preferably 10 or less, more preferably 7 or less, and further preferably 3 or more and 10 or less, and more preferably 5 or more and 7 or less, from the viewpoint of the absorption capacity and the absorption rate at the time of body fluid discharge and no discomfort at the time of wearing.

In the sanitary napkin 1 of the above embodiment, the antimicrobial agent is disposed in the second region F of the central absorbent sheet 402 constituting the central absorbent portion 43, and the first region E may or may not contain the antimicrobial agent. In the case where the first zone E contains an antibacterial agent, the same kind of antibacterial agent as that of the second zone F may be contained as the antibacterial agent. The antimicrobial agent disposed in the first region E is preferably sparingly water-soluble, and among these, a quaternary ammonium salt that is insoluble or sparingly water-soluble is preferable. In the first region, since the fiber density is lower than that in the second region, the antimicrobial agent, which is a water-insoluble or water-insoluble but ionic quaternary ammonium salt, is dispersed in the body fluid and easily moves together with the body fluid to the second region F where the fiber density is relatively high. By moving the antibacterial agent together with the body fluid, the concentration of the antibacterial agent in the second region F is increased, and high antibacterial performance can be exhibited. In this case, as shown in the sanitary napkin 1, when the first region E is located on the side closest to the skin-facing surface and the second region F is located on the side not closest to the skin-facing surface, part of the body fluid is retained in the first region E containing the super absorbent polymer, and the body fluid containing organic substances such as proteins that are not easily absorbed by the super absorbent polymer is easily guided to the second region F having a relatively high fiber density. Therefore, it is possible to effectively suppress the generation of odor from organic matter in the second region F, which is an environment in which a high concentration of the antibacterial agent is present. In this case, since the antimicrobial agent in the first region E is insoluble or sparingly soluble in water, all of the antimicrobial agent does not migrate to the second region F and easily remains, and therefore, the generation of odor from organic substances present in the body fluid retained in the first region E can be suppressed.

The absorbent article for absorbing menstrual blood of the present invention may be a sanitary pad (vaginal discharge pad) or the like, in addition to the sanitary napkin.

The following absorbent article is further disclosed with respect to the above-described embodiments of the present invention.

[ 1 ] an absorbent article comprising a liquid-permeable front sheet forming a skin-facing surface, a back sheet forming a non-skin-facing surface, and an absorbent body located between the two sheets and including an absorbent sheet containing a fibrous material as a constituent member, the absorbent body having a longitudinal direction corresponding to the front-back direction of a wearer and a transverse direction orthogonal to the longitudinal direction, the absorbent body having a laminated structure at least in the central portion of the transverse direction of the absorbent body, the laminated structure comprising 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 the two sheets, the central absorbent portion having a first region and a second region in which the density of the fibrous material is higher than that of the first region in the thickness direction thereof, and an antimicrobial agent being disposed in the second region.

< 2 > the absorbent article according to < 1 > above, wherein the central absorbent portion has a structure in which central absorbent sheets are laminated in a plurality of layers, and a second region laminated portion in which a plurality of the second regions are directly laminated without interposing the first regions therebetween is provided on a non-skin-facing surface side in a thickness direction of the central absorbent portion.

< 3 > the absorbent article according to the above < 2 >, wherein the antimicrobial agent is disposed over the entire area of the second region laminated part in a plan view of the absorbent body.

< 4 > the absorbent article as described in any of above < 1 > to < 3 >, wherein as the above-mentioned antibacterial agent, a water-insoluble or poorly water-soluble antibacterial agent is contained.

< 5 > the absorbent article as stated in above < 4 >, wherein the above-mentioned water-insoluble or poorly water-soluble antibacterial agent is an antibacterial metal carrier.

< 6 > the absorbent article as stated in above < 5 >, wherein the carrier of the above antibacterial metal carrier is a hydrophobic porous particle.

< 7 > the absorbent article according to any one of the above < 4 > to < 6 >, wherein the antibacterial agent comprises an organic antibacterial agent.

< 8 > the absorbent article according to < 7 > above, wherein the organic antibacterial agent is a water-insoluble or poorly water-soluble quaternary ammonium salt.

< 9 > the absorbent article as described in any of above < 4 > to < 8 >, wherein as the above-mentioned antibacterial agent, the above-mentioned water-insoluble or poorly water-soluble antibacterial agent is contained, and a water-soluble antibacterial agent is contained.

< 10 > the absorbent article according to any one of the above < 1 > to < 9 >, wherein the central absorbent portion has a structure in which central absorbent sheets are laminated in a plurality of layers, and the content of the antimicrobial agent is 0.001 mass% or more and 12 mass% or less, preferably 0.01 mass% or more and 5 mass% or less, with respect to the total mass of the central absorbent sheets.

< 11 > the absorbent article as defined in any of above < 1 > to < 10 > wherein said central absorbent portion contains a deodorant.

< 12 > the absorbent article as stated in above < 11 >, wherein at least said second region contains said deodorant.

< 13 > the absorbent article as stated above < 11 > or < 12 > wherein the above deodorant contains porous particles.

< 14 > the absorbent article as stated in any one of above < 11 > to < 13 > wherein as said deodorant, a pH buffering agent is contained.

< 15 > the absorbent article as stated above < 14 >, wherein as the above pH buffering agent, citric acid and tris (hydroxymethyl) aminomethane are contained.

< 16 > the absorbent article according to any one of the above < 1 > to < 15 >, wherein the central absorbent portion contains a perfume.

< 17 > the absorbent article according to any one of the above < 1 > to < 16 >, wherein the absorbent body has a slit penetrating the front side absorbent sheet and reaching the inside in the thickness direction of the central absorbent portion in a region where the front side absorbent sheet, the central absorbent sheet constituting the central absorbent portion, and the back side absorbent sheet are superposed.

< 18 > the absorbent article as stated in above < 17 >, wherein the longitudinal direction of said slit extends in parallel with said longitudinal direction.

< 19 > the absorbent article according to < 17 > or < 18 > wherein the slit has a longitudinal length of 10mm to 35mm, preferably 15mm to 25 mm.

< 20 > the absorbent article as defined in any of the above < 17 > to < 19 >, wherein the slit has an opening width of 1.2mm or less, preferably 1.0mm or less, more preferably 0.5mm or less.

< 21 > the absorbent article as defined in any of above < 17 > to < 20 >, wherein a plurality of said slits are arranged dispersedly in both said longitudinal direction and said transverse direction.

< 22 > the absorbent article as defined in any of above < 1 > to < 21 > wherein the above-mentioned first region contains a super absorbent polymer.

< 23 > the absorbent article as stated above < 22 > wherein the content of said super absorbent polymer in said first region is greater than the content of said second region.

< 24 > the absorbent article as stated in the above < 22 > or < 23 >, wherein the above-mentioned super absorbent polymer has a water absorption rate of 20mL/0.3 g.30 sec or less, preferably 2mL/0.3 g.30 sec or more and 15mL/0.3 g.30 sec or less, more preferably 4mL/0.3 g.30 sec or more and 10mL/0.3 g.30 sec or less.

< 25 > the absorbent article as defined in any of above < 1 > to < 24 > wherein the above absorbent body has a large thickness portion at the excretion portion-facing portion.

< 26 > the absorbent article as stated in above < 25 >, wherein the width of said central absorbent portion is smaller than the total width of the absorbent body.

< 27 > the absorbent article according to the above < 26 >, wherein the width of the central absorbent portion is 25% to 75%, preferably 40% to 60%, of the total width of the absorbent body of the portion where the central absorbent portion is present.

< 28 > the absorbent article according to any one of the above < 25 > to < 27 >, wherein 50% or more of the entire length in the longitudinal direction of the large-thickness portion is present in the excretion portion-opposing portion.

< 29 > the absorbent article according to < 28 > wherein the longitudinal length of the central absorbent portion is 5% to 65%, preferably 15% to 55%, of the total length of the absorbent body in the longitudinal direction.

< 30 > the absorbent article as defined in any of above < 1 > to < 29 > wherein the above-mentioned first region also contains an antibacterial agent.

< 31 > the absorbent article as stated in above < 30 >, wherein the above-mentioned antibacterial agent contained in the above-mentioned first region is water-insoluble or poorly water-soluble.

< 32 > the absorbent article as stated in above < 31 >, wherein the antibacterial agent contained in the above-mentioned first region is a quaternary ammonium salt which is insoluble or poorly soluble in water.

< 33 > the absorbent article as defined in any of above < 1 > to < 32 > wherein the above absorbent article is a sanitary napkin.

Industrial applicability

The absorbent article of the present invention has excellent persistence of the antibacterial effect.

Claims

1. An absorbent article comprising a liquid-permeable front face sheet forming a skin-facing surface, a back face sheet forming a non-skin-facing surface, and an absorbent body located between the sheets and including an absorbent sheet containing a fibrous material as a constituent element, the absorbent article having a longitudinal direction corresponding to a front-back direction of a wearer and a transverse direction orthogonal to the longitudinal direction, the absorbent article being characterized in that:

the absorbent body has a laminated structure including a front side absorbent sheet on a skin-facing surface side, a back side absorbent sheet on a non-skin-facing surface side, and a central absorbent portion between the sheets, at least in a central portion of the absorbent body in the lateral direction,

the central absorbent portion has, in a thickness direction thereof, a first region containing cellulose-based fibers and a second region containing cellulose-based fibers and having a higher density of a fiber material than the first region, the density of the fiber material being an area of the fibers per unit area,

an antibacterial agent is disposed in the second region, and as the antibacterial agent, a water-insoluble or water-sparingly-soluble antibacterial agent which is an antibacterial metal support, the antibacterial agent having a solubility of less than 20g per 100g of ion-exchanged water at 25 ℃ is contained,

the central absorbent portion has a structure in which central absorbent sheets are laminated in a plurality of layers, and has a second region laminated portion in which a plurality of the second regions are directly laminated without interposing the first regions therebetween, on a non-skin-facing surface side in a thickness direction of the central absorbent portion,

the first region and the second region both contain a superabsorbent polymer, the superabsorbent polymer being present in the first region in an amount greater than the second region.

2. The absorbent article of claim 1, wherein:

the superabsorbent polymer has a water absorption rate of 20mL/0.3 g.30 seconds or less.

3. The absorbent article of claim 1 or 2, wherein:

the antimicrobial agent is disposed over the entire second region laminated section in a plan view of the absorbent body.

4. The absorbent article of claim 1 or 2, wherein:

the carrier of the antibacterial metal carrier is hydrophobic porous particles.

5. The absorbent article of claim 1 or 2, wherein:

the antibacterial agent includes an organic antibacterial agent.

6. The absorbent article of claim 5, wherein:

the organic antibacterial agent is a water-insoluble or water-insoluble quaternary ammonium salt.

7. The absorbent article of claim 1 or 2, wherein:

the antibacterial agent is a water-insoluble or poorly water-soluble antibacterial agent, and a water-soluble antibacterial agent is also contained.

8. The absorbent article of claim 1 or 2, wherein:

the content of the antimicrobial agent is 0.001 mass% or more and 12 mass% or less with respect to the total mass of the central absorbent sheet.

9. The absorbent article of claim 1 or 2, wherein:

the central absorbent portion contains a deodorant.

10. The absorbent article of claim 9, wherein:

at least the second region contains the odor control agent.

11. The absorbent article of claim 9, wherein:

as the deodorant, porous particles are contained.

12. The absorbent article of claim 9, wherein:

as the deodorant, a pH buffer is contained.

13. The absorbent article of claim 12, wherein:

as the pH buffer, citric acid and tris (hydroxymethyl) aminomethane are contained.

14. The absorbent article of claim 1 or 2, wherein:

the central absorption part contains a perfume.

15. The absorbent article of claim 1 or 2, wherein:

the absorbent body has a slit that penetrates the front side absorbent sheet and reaches the inside in the thickness direction of the central absorbent portion in a region where the front side absorbent sheet, the central absorbent sheet that constitutes the central absorbent portion, and the back side absorbent sheet overlap.

16. The absorbent article of claim 15, wherein:

the slot has a length direction extending parallel to the longitudinal direction.

17. The absorbent article of claim 15, wherein:

the length of the slit in the longitudinal direction is 10mm to 35 mm.

18. The absorbent article of claim 15, wherein:

the slit has an opening width of 1.2mm or less.

19. The absorbent article of claim 15, wherein:

the plurality of slits are arranged so as to be dispersed in both the longitudinal direction and the transverse direction.

20. The absorbent article of claim 1 or 2, wherein:

the absorbent body has a large thickness portion at the excretion portion facing portion.

21. The absorbent article of claim 20, wherein:

the width of the central absorbent portion is less than the total width of the absorbent body.

22. The absorbent article of claim 21, wherein:

the width of the central absorbent portion is 25% to 75% of the total width of the absorbent body in the portion where the central absorbent portion is present.

23. The absorbent article of claim 20, wherein:

the large-thickness portion is present at the excretion portion-facing portion over 50% or more of the entire length in the longitudinal direction.

24. The absorbent article of claim 23, wherein:

the longitudinal length of the central absorbent portion is 5% to 65% of the total length of the absorbent body in the longitudinal direction.

25. The absorbent article of claim 1 or 2, wherein:

an antimicrobial agent is also contained in the first zone.

26. The absorbent article of claim 25, wherein:

the antimicrobial agent contained in the first region is water-insoluble or poorly water-soluble.

27. The absorbent article of claim 26, wherein:

the antimicrobial agent contained in the first region is a quaternary ammonium salt that is insoluble or poorly soluble in water.

28. The absorbent article of claim 1 or 2, wherein:

the absorbent article is a sanitary napkin.