Absorbent article

Abstract

Provided is an absorbent article comprising: an antibacterial liquid that includes an antibacterial agent and an organic solvent; and a highly water-absorbent polymer. The absorbent article can demonstrate both antibacterial performance and absorption performance. An absorbent article (1) comprises: an absorbent body (4) on which a highly water-absorbent polymer is supported; and an antibacterial liquid that includes an antibacterial agent and an organic solvent. The antibacterial liquid covers the highly water-absorbent polymer positioned at a central section in the width direction of the absorbent body (4). The antibacterial liquid does not cover the highly water-absorbent polymers positioned outside the central section, on both sides in the width direction of the absorbent body (4).

Description

absorbent articles

[0001] The present invention relates to absorbent articles, and in particular to absorbent articles comprising antimicrobial liquids.

[0002] There is known an absorbent article comprising an antibacterial liquid containing an antibacterial agent and an organic solvent, and a superabsorbent polymer. For example, Patent Document 1 discloses a water-absorbent resin composition comprising an organic hydrophobic antibacterial agent, an organic solvent in which the organic hydrophobic antibacterial agent is soluble, and a water-absorbent resin, and an absorbent article comprising the water-absorbent resin composition. The organic hydrophobic antibacterial agent, the organic solvent, and an ionic compound that suppresses evaporation of the organic hydrophobic antibacterial agent are present on the surface of the water-absorbent resin.

[0003] Japanese Patent Application Laid-Open No. 2019-38882

[0004] In the absorbent article of Patent Document 1, an antibacterial liquid (an organic hydrophobic antibacterial agent and an organic solvent) is attached to the surface of a superabsorbent polymer (a water-absorbent resin). Therefore, in the absorbent article, the absorption rate of the superabsorbent polymer of the absorbent article may be slowed, which may result in a decrease in the absorbent performance of the absorbent article. This may delay the absorption of body fluids in the absorbent article, causing leakage of body fluids from the widthwise ends of the absorbent article, i.e., side leakage. However, reducing the amount of antibacterial liquid attached to the surface of the superabsorbent polymer may also result in a decrease in antibacterial performance.

[0005] Therefore, an object of the present invention is to provide an absorbent article that is capable of achieving both antibacterial performance and absorption performance (absorption speed, etc.) in an absorbent article that comprises an antibacterial liquid containing an antibacterial agent and an organic solvent, and a superabsorbent polymer.

[0006] One aspect of the present invention is an absorbent article having a longitudinal direction, a width direction, and a thickness direction that are perpendicular to each other, and comprising an absorbent body carrying a superabsorbent polymer, and further comprising an antibacterial liquid containing an antibacterial agent and an organic solvent, wherein the antibacterial liquid coats a large amount of the superabsorbent polymer located in a central part of the absorbent body in the width direction, and coats a small amount of the superabsorbent polymer located on both sides of the central part of the absorbent body in the width direction.

[0007] According to the present invention, an absorbent article can be provided that is equipped with an antibacterial liquid containing an antibacterial agent and an organic solvent, and a superabsorbent polymer, and that can achieve both antibacterial performance and absorption performance (absorption speed, etc.).

[0008] Fig. 1 is a plan view showing a configuration example of a light incontinence pad according to an embodiment. Fig. 2 is a cross-sectional view taken along the line CW-CW in Fig. 1. Fig. 3 is a plan view showing a configuration example of a first absorbent layer of an absorber of a light incontinence pad according to an embodiment. Fig. 4 is a plan view showing a configuration example of a second absorbent layer of an absorber of a light incontinence pad according to an embodiment.

[0009] The present disclosure relates to the following aspects: [Aspect 1] An absorbent article having a longitudinal direction, a width direction, and a thickness direction that are orthogonal to one another, and including an absorbent body carrying a superabsorbent polymer, further including an antibacterial liquid containing an antibacterial agent and an organic solvent, wherein the antibacterial liquid coats a large amount of the superabsorbent polymer located in a central portion of the absorbent body in the width direction, and coats a small amount of the superabsorbent polymer located on both sides of the central portion in the width direction of the absorbent body.

[0010] In this absorbent article, the antibacterial liquid coats a large amount of the superabsorbent polymer located in the widthwise central portion of the absorbent body, while coating a small amount of the superabsorbent polymer located on both sides of the widthwise central portion of the absorbent body (preferably, no coating). Therefore, when body fluid is excreted in the widthwise central portion of the absorbent body and comes into contact with the antibacterial liquid coating the superabsorbent polymer, the antibacterial agent in the antibacterial liquid can exhibit antibacterial properties. In addition, because the superabsorbent polymer in the widthwise central portion of the absorbent body is coated with the antibacterial liquid, the absorption rate of the body fluid by the superabsorbent polymer in the widthwise central portion can be slowed. This suppresses absorption of body fluid by the superabsorbent polymer in the widthwise central portion, making it easier for the body fluid to diffuse to both widthwise outer sides of the central portion. In other words, the diffusion of body fluid to both widthwise outer sides can be improved. Furthermore, the diffused body fluid can be more easily absorbed by the superabsorbent polymer located on both widthwise outer sides of the central portion, which are less covered with the antibacterial liquid. This allows for a wider range of absorbent materials to be used, and also prevents side leakage of body fluids from the widthwise ends of the absorbent article, thereby achieving both antibacterial and absorbent properties in an absorbent article comprising an antibacterial liquid and a highly absorbent polymer.

[0011] [Aspect 2] The absorbent article according to aspect 1, further comprising an upper-layer absorbent body including the absorber, and a lower-layer absorbent body located closer to the skin than the upper-layer absorbent body in the thickness direction.

[0012] This absorbent article further includes an upper absorbent body including the aforementioned absorbent body and a lower absorbent body. Therefore, when body fluid passes through the upper absorbent body, it comes into contact with the antibacterial liquid coating the superabsorbent polymer, allowing the antibacterial agent in the antibacterial liquid to exhibit antibacterial properties. In addition, because the superabsorbent polymer in the central portion of the upper absorbent body is coated with the antibacterial liquid, absorption of body fluid by the superabsorbent polymer in the central portion can be suppressed. This facilitates transfer of body fluid to the lower absorbent body. Since the antibacterial liquid gradually transfers to the lower absorbent body each time body fluid transfers to the lower absorbent body, the amount of antibacterial liquid in the lower absorbent body can be increased. In other words, the antibacterial properties of the lower absorbent body can be enhanced depending on the amount of body fluid. Furthermore, not only during the first absorption of body fluid, but also during subsequent absorptions, the upper absorbent body suppresses absorption of body fluid by the superabsorbent polymer in the central portion, thereby improving the rewetability of the absorbent article. Furthermore, in the upper absorbent body, the superabsorbent polymer on both outer sides of the central portion, which is not covered much with the antibacterial liquid, generally maintains its original absorption performance, allowing the superabsorbent polymer to absorb body fluids, thereby further suppressing side leakage of body fluids.

[0013] [Aspect 3] The absorbent article according to Aspect 2, wherein a portion of the antibacterial liquid is contained in the lower-layer absorbent body, and the amount of the antibacterial liquid contained in the upper-layer absorbent body is greater than the amount of the antibacterial liquid contained in the lower-layer absorbent body.

[0014] In this absorbent article, a portion of the antibacterial liquid is contained in the lower absorbent body, and the amount of antibacterial liquid in the upper absorbent body is greater than that of the lower absorbent body. The presence of a small amount of antibacterial liquid in the lower absorbent body allows the article to exhibit antibacterial properties efficiently from the first absorption of body fluids.

[0015] [Aspect 4] The absorbent article according to Aspect 2 or 3, wherein the upper-layer absorbent body has, in a plan view, a superabsorbent polymer-present region where the superabsorbent polymer is present and a superabsorbent polymer-absent region where the superabsorbent polymer is not present, and the superabsorbent polymer-absent region has a compressed portion formed by compressing the upper-layer absorbent body in the thickness direction.

[0016] In this absorbent article, the upper absorbent body has, in a plan view, a region containing a superabsorbent polymer and a region not containing a superabsorbent polymer, and the region not containing a superabsorbent polymer has compressed portions. This allows bodily fluid to migrate from the upper absorbent body to the lower absorbent body via the compressed portions without being inhibited by the superabsorbent polymer, thereby improving fluid migration from the upper absorbent body to the lower absorbent body. This further reduces side leakage of bodily fluid.

[0017] [Aspect 5] The absorbent article according to any one of Aspects 2 to 4, wherein at least the lower absorbent of the upper absorbent and the lower absorbent contains pulp fibers, and the amount of the pulp fibers contained in the lower absorbent is greater than the amount of the pulp fibers contained in the upper absorbent.

[0018] In this absorbent article, the amount of pulp fiber contained in the lower absorbent body is greater than the amount of pulp fiber contained in the upper absorbent body. As a result, the upper absorbent body has fewer pulp fibers that easily retain body fluids around the antibacterial agent (superabsorbent polymer), allowing the antibacterial effect of the antibacterial agent in the upper absorbent body to be sustained. Meanwhile, the lower absorbent body has more pulp fibers, allowing it to quickly absorb and retain body fluids more easily. In this case, the lower absorbent body is physically separated from the body, allowing it to retain body fluids, thereby preventing skin rashes.

[0019] [Aspect 6] The absorbent article according to any one of Aspects 2 to 5, wherein the antibacterial liquid coats a large amount of the superabsorbent polymer located in a central portion of the absorbent body in the longitudinal direction, and coats a small amount of the superabsorbent polymer located forward of the central portion of the absorbent body in the longitudinal direction.

[0020] In this absorbent article, the antibacterial liquid covers a large amount of the superabsorbent polymer located in the longitudinal center of the (upper layer) absorbent body, and a small amount (preferably no coverage) of the superabsorbent polymer located forward (ventral side) of the longitudinal center of the (upper layer) absorbent body (preferably no coverage). This suppresses absorption of body fluids by the superabsorbent polymer in the longitudinal center, allowing the superabsorbent polymer on the longitudinal ventral side of the central portion, which is less covered with antibacterial liquid, to easily absorb body fluids. Furthermore, the antibacterial liquid is not present in the (upper layer) absorbent body at the abdominal side (front longitudinal portion), which is likely to come into direct or indirect surface contact with the (upper layer) absorbent body. This suppresses contact between the antibacterial liquid and the body, and prevents the antibacterial agent contained in the antibacterial liquid from irritating the skin.

[0021] [Aspect 7] The absorbent article according to any one of Aspects 2 to 6, wherein the upper-layer absorbent body has a skin-side portion located on the skin side in the thickness direction and a non-skin-side portion located on the non-skin side of the skin-side portion in the thickness direction, and the water retention rate of the skin-side portion is lower than the water retention rate of the non-skin-side portion.

[0022] In this absorbent article, the water retention rate of the skin-side portion of the upper absorbent body is relatively low. Therefore, the skin-side portion, which is the surface side of the upper absorbent body, can be kept appropriately dry (smooth). On the other hand, the water retention rate of the non-skin-side portion of the upper absorbent body is relatively high. Therefore, the non-skin-side portion, which is the back side of the upper absorbent body, can be sufficiently brought into contact with the superabsorbent polymer coated with the antibacterial agent and body fluids. This enhances the antibacterial performance of the antibacterial agent.

[0023] [Aspect 8] The absorbent article according to any one of Aspects 2 to 7, wherein the lower absorbent body includes an absorbent core, a skin-side core wrap sheet covering the skin side of the absorbent core in the thickness direction, and a non-skin-side core wrap sheet covering the non-skin side of the absorbent core in the thickness direction, the skin-side core wrap sheet and the non-skin-side core wrap sheet being made of crepe paper having an uneven surface, and the unevenness of the skin-side core wrap sheet is smaller than the unevenness of the non-skin-side core wrap sheet.

[0024] In this absorbent article, the unevenness of the skin-side core wrap sheet, which is made of uneven crepe paper in the lower absorbent body, is relatively small. This improves the liquid diffusion in the planar direction of the skin-side core wrap sheet, and also increases the contact area between the upper absorbent body and the skin-side core wrap sheet, as well as the contact area between the skin-side core wrap sheet and the absorbent core. This allows bodily fluid released into the absorbent article and transferred from the upper absorbent body to the skin-side core wrap sheet during use to be diffused in the planar direction of the skin-side core wrap sheet and then transferred to the absorbent core. Meanwhile, the unevenness of the non-skin-side core wrap sheet, made of crepe paper, is relatively large, making the non-skin-side core wrap sheet more deformable. This allows the non-skin-side core wrap sheet to follow the expansion and contraction of the absorbent article due to the user's body movements during use, thereby preventing breakage. In this case, the unevenness of the non-skin side core wrap sheet absorbs the external force caused by body movement, reducing the external force acting on the skin side core wrap sheet and preventing breakage of the skin side core wrap sheet.

[0025] The absorbent article according to the embodiment will be described below using a light incontinence pad as an example. However, the type of absorbent article is not limited to this example, and other types of absorbent articles may be used without departing from the scope of the present invention. Examples of such absorbent articles include pants-type diapers, tape-type diapers, sanitary napkins, and panty liners.

[0026] 1 and 2 are diagrams showing an example of the configuration of a light incontinence pad 1 according to an embodiment. Fig. 1 is a plan view showing an example of the configuration of a light incontinence pad according to an embodiment. Fig. 2 is a schematic cross-sectional view taken along line CW-CW in Fig. 1.

[0027] In the unfolded state shown in Fig. 1 , the light incontinence pad 1 has a longitudinal direction L, a width direction W, and a thickness direction T that are perpendicular to each other, and has a longitudinal centerline CL that passes through the center of the width direction W and extends in the longitudinal direction L, and a widthwise centerline CW that passes through the center of the longitudinal direction L and extends in the width direction W. Here, the directions and sides approaching the longitudinal centerline CL are referred to as the inward and inner sides of the width direction W, respectively, and the directions and sides moving away from the longitudinal centerline CL are referred to as the outward and outer sides of the width direction W, respectively. Meanwhile, the directions and sides approaching the widthwise centerline CW are referred to as the inward and inner sides of the longitudinal direction L, respectively, and the directions and sides moving away from the widthwise centerline CW are referred to as the outward and outer sides of the longitudinal direction L, respectively. In addition, the side in the longitudinal direction L toward the edge (ventral edge) of the light incontinence pad 1 that corresponds to the wearer's abdomen is also referred to as the front side of the longitudinal direction L, and the side toward the edge (dorsal edge) of the light incontinence pad 1 that corresponds to the wearer's back is also referred to as the rear side of the longitudinal direction L. Furthermore, "planar view" refers to the state in which the light incontinence pad 1 is viewed from above in the thickness direction T when unfolded on a plane including the longitudinal direction L and the width direction W, and "planar shape" refers to the shape as perceived in a planar view. "Planar direction" refers to any direction parallel to a plane including the width direction W and the longitudinal direction L. "Skin side" and "non-skin side" refer to the side that is relatively closer to and farther from the wearer's skin in the thickness direction T when the light incontinence pad 1 is worn by a wearer. "A direction along the longitudinal direction L" is not limited to being parallel to the longitudinal direction L, but also includes a range of ±30° with respect to the longitudinal direction L. "A direction along the width direction W" is not limited to being parallel to the width direction W, but also includes a range of ±30° with respect to the width direction W. These definitions apply not only to the light incontinence pad 1 but also to the absorbent body of the light incontinence pad 1 and the various materials disposed therein.

[0028] 1 , the light incontinence pad 1 is rectangular in plan view having long sides extending in the longitudinal direction L and short sides extending in the width direction W, with both edges in the longitudinal direction L corresponding to the short sides bulging in an arc shape. However, in this embodiment, the shape of the light incontinence pad 1 is not limited to this example, and may be any shape as long as the length in the longitudinal direction L is longer than the length in the width direction W. Examples of such shapes include a rectangle, a rectangle with rounded corners, an oval, a gourd shape, and an hourglass shape.

[0029] As shown in Figure 2, the light incontinence pad 1 comprises a liquid-permeable topsheet 2 positioned on the skin side, a liquid-impermeable backsheet 3 positioned on the non-skin side, and an absorbent body 4 positioned between the topsheet 2 and the backsheet 3 to absorb and retain liquid. Examples of materials for the topsheet 2 include liquid-permeable nonwoven fabrics or woven fabrics, synthetic resin films with liquid-permeable holes, and combinations of the same or different types of these. Examples of materials for the backsheet 3 include liquid-impermeable but breathable nonwoven fabrics, synthetic resin films with air holes, and combinations of the same or different types of these. A liquid-permeable diffusion sheet positioned between the topsheet 2 and the absorbent body 4 to diffuse liquid in the planar direction may also be provided.

[0030] Materials for the absorbent body 4 include superabsorbent polymer (SAP), and may include pulp fibers. The absorbent body 4 may include a liquid-permeable core wrap sheet that encapsulates the superabsorbent polymer (and pulp fibers). As shown in FIG. 2 , the absorbent body 4 may have a two-layer structure (upper absorbent body 11 and lower absorbent body 12 (described later)), a single-layer structure (e.g., upper absorbent body 11 or lower absorbent body 12), or a multi-layer structure of three or more layers. An absorbent body 4 with a relatively thin single-layer structure may also be referred to as an absorbent sheet, and particularly when the main material is a superabsorbent polymer, it may also be referred to as an SAP sheet.

[0031] In this embodiment, the non-skin side surface of the topsheet 2 and the skin side surface of the absorbent body 4 are bonded to each other, and the non-skin side surface of the absorbent body 4 and the skin side surface of the backsheet 3 are bonded to each other. The peripheral edge portions of the non-skin side surface of the topsheet 2 and the skin side surface of the backsheet 3 are bonded to each other.

[0032] An example of the topsheet 2 is a flat sheet without any irregularities. However, the topsheet 2 is not limited to this example, and is not particularly limited as long as it can be used as a topsheet of an absorbent article. The topsheet 2 may be, for example, a sheet extending in the longitudinal direction L and including a plurality of convex portions spaced apart in the width direction W and a plurality of concave portions provided between each of the plurality of convex portions, or a sheet having a plurality of convex portions that are substantially circular in plan view and arranged in a checkerboard pattern in plan view.

[0033] The type of nonwoven fabric in the topsheet 2 and backsheet 3 is not particularly limited as long as it can be used as a nonwoven fabric for absorbent articles, and examples include meltblown nonwoven fabric, spunbond nonwoven fabric, airlaid nonwoven fabric, and air-through nonwoven fabric.

[0034] The material for the nonwoven fabric is not particularly limited as long as it can be used as a material for absorbent articles, and examples thereof include synthetic resin fibers and pulp fibers. The synthetic resin is not particularly limited as long as it can be used as a material for absorbent articles, and examples thereof include olefin resins such as polyethylene and polypropylene, polyamide resins such as 6-nylon and 6,6-nylon, and polyester resins such as polyethylene terephthalate and polybutylene terephthalate. The pulp fiber is not particularly limited as long as it can be used as a material for absorbent articles, and an example thereof is cellulosic fibers. Examples of cellulosic fibers include wood pulp, crosslinked pulp, non-wood pulp, regenerated cellulose, and semi-synthetic cellulose.

[0035] The type of synthetic resin film for the topsheet 2 and the backsheet 3 is not particularly limited as long as it can be used as a film for an absorbent article, and known film materials can be used. The material for the synthetic resin film is not particularly limited as long as it can be used as a material for an absorbent article, and the synthetic resins described above can be used.

[0036] The type of superabsorbent polymer in the absorbent body 4 is not particularly limited as long as it is a polymer that can absorb and retain water, and examples thereof include polyacrylate-based, polysulfonate-based, and maleic anhydride-based superabsorbent polymers. The types of pulp fibers are as described above. The proportion of pulp fibers in the absorbent body 4 may be, for example, in the range of 0 to 90% by mass of the superabsorbent polymer.

[0037] As shown in FIG. 2 , in this embodiment, the light incontinence pad 1 further includes a pair of side sheets 7, linear elastic members 8a and 8b, an outer sheet 9, and a fixing portion 10. The pair of side sheets 7 are arranged to cover both surfaces of the topsheet 2 in the width direction W. The inner portions of the pair of side sheets 7 in the width direction W form a pair of leakage barriers extending in the longitudinal direction L. The pair of leakage barriers are folded upright on both surfaces of the topsheet 2 in the width direction W, with the inner edges in the width direction W being free ends. The linear elastic member 8a is a linear elastic body extending along the longitudinal direction L near the free ends of the pair of leakage barriers. The linear elastic member 8a contracts the inner edges of the pair of leakage barriers in the width direction W, causing the leakage barriers to stand up and form gathered portions. The outer sheet 9 is joined to the non-skin-facing surface of the backsheet 3, and is joined to the pair of side sheets 7 at its peripheral edges. The linear elastic members 8b are linear elastic bodies extending in the longitudinal direction L between the outer sheet 9 and the pair of side sheets 7 at both ends in the width direction W of the outer sheet 9 and the pair of side sheets 7. The linear elastic members 8b contract the outer edges of the light incontinence pad 1 in the width direction W to function as leg gathers. An example of the material for each linear elastic member is rubber thread. The fixing parts 10 are elongated rectangular adhesive tapes attached along the longitudinal direction L to the side of the outer sheet 9 opposite the back sheet 3. In this embodiment, six fixing parts 10 are provided aligned in the width direction W. The fixing parts 10 fix the light incontinence pad 1 to a packaging sheet (not shown) via a separator when the light incontinence pad 1 is individually packaged, and re-fix the light incontinence pad 1 to the wearer's underwear or the like when the light incontinence pad 1 is in use.

[0038] The basis weights of the top sheet 2, back sheet 3, and absorbent body 4 are adjusted appropriately depending on the absorption performance required for the light incontinence pad 1, but are not particularly limited as long as they can be used as sheets for the light incontinence pad 1. The basis weight of the top sheet 2 is, for example, 5 to 200 g / m ２ The basis weight of the back sheet 3 is, for example, 5 to 200 g / m ２ The basis weight of the absorbent body 4 is, for example, 10 to 2000 g / m ２ Examples include:

[0039] The light incontinence pad 1 further includes an antibacterial liquid containing an antibacterial agent and an organic solvent. The antibacterial liquid coats a large amount of the superabsorbent polymer located in the central portion of the absorbent body 4 in the width direction W. However, the antibacterial liquid coats a small amount of the superabsorbent polymer located on both sides of the central portion of the absorbent body 4 in the width direction W (preferably, the amount of coating is not zero (not coated)). In other words, the antibacterial liquid coats only the superabsorbent polymer located approximately in the central portion of the width direction W of the superabsorbent polymer in the absorbent body 4, and hardly coats the outer portions. It is sufficient that at least a portion of the antibacterial liquid is contained in the absorbent body 4, and at least a portion of the antibacterial liquid contained in the absorbent body 4 coats a predetermined superabsorbent polymer. In other words, it is not necessary for the antibacterial agent to coat the superabsorbent polymer entirely.

[0040] Here, the central portion of the width direction W of the absorbent body 4 may be, for example, a central portion (one portion) excluding both end portions (one portion each) when the absorbent body 4 is divided into thirds in the width direction W, a central portion (two portions) excluding both end portions (one portion each) when the absorbent body 4 is divided into four equal portions in the width direction W, or a central portion (three or one portion) excluding both end portions (one or two portions each) when the absorbent body 4 is divided into five equal portions in the width direction W. However, the boundaries may deviate slightly (by about ±20%).

[0041] Furthermore, the antibacterial liquid may cover a large amount of the superabsorbent polymer located in the central part of the absorbent body 4 in the longitudinal direction L, and a small amount of the superabsorbent polymer located on both sides of the central part of the absorbent body 4 in the longitudinal direction L (preferably, the amount of coverage may be zero (no coverage)). In other words, the antibacterial liquid may cover only the superabsorbent polymer located approximately in the central part of the longitudinal direction L among the superabsorbent polymers in the absorbent body 4, and may barely cover the outer parts. Here, examples of the central portion of the absorbent body 4 in the longitudinal direction L include, in a plan view, the central portion (one portion) excluding both end portions (one portion each) when the absorbent body 4 is divided into thirds in the longitudinal direction L, the central portion (two portions) excluding both end portions (one portion each) when the absorbent body 4 is divided into four equal portions in the longitudinal direction L, the central portion (three or one portion) excluding both end portions (one or two portions each) when the absorbent body 4 is divided into five equal portions in the longitudinal direction L, and portions shifted 10 to 30% forward in the longitudinal direction L. However, the boundary may be shifted slightly (by approximately ±20%).

[0042] 1 , in this embodiment, the central portion in the longitudinal direction L and the central portion in the width direction W of the absorbent 4 of the light incontinence pad 1 in a plan view is also referred to as the central region TA (note that these definitions are also used for the topsheet 2 and the backsheet 3 that overlap the absorbent 4 in the thickness direction T). The central region TA is a portion that includes the excretory opening contact area in a plan view, and the antibacterial solution is present at least in the central region TA. In this embodiment, the central region TA is the central portion (two portions) when the absorbent 4 is divided into four equal parts in the longitudinal direction L and the central portion (one portion) when the absorbent 4 is divided into three equal parts in the width direction W in a plan view.

[0043] The method for coating the superabsorbent polymer with the antibacterial liquid is not particularly limited, and any method can be used. For example, (a) a method is considered in which the antibacterial liquid is applied to the superabsorbent polymer material using a spray device before forming the absorbent body. In this case, the superabsorbent polymer coated with the antibacterial liquid is placed in a predetermined region of the absorbent body to form an absorbent body having the superabsorbent polymer coated with the antibacterial liquid in a predetermined region. Alternatively, (b) a method is considered in which the superabsorbent polymer is placed on a core wrap sheet, and the antibacterial liquid is applied from above to the superabsorbent polymer in a predetermined region of the placed superabsorbent polymer using a spray device. In this case, the superabsorbent polymer coated with the antibacterial liquid is wrapped in the core wrap sheet to form an absorbent body having the superabsorbent polymer coated with the antibacterial liquid in a predetermined region. Alternatively, (c) a method is considered in which an absorbent body is formed having the superabsorbent polymer wrapped in the core wrap sheet, and the antibacterial liquid is applied to a predetermined region of the core wrap sheet of the absorbent body using a spray device. In this case, the antibacterial liquid migrates from the core wrap sheet to the superabsorbent polymer, thereby forming an absorbent body having a superabsorbent polymer with the antibacterial liquid applied in a predetermined area. Alternatively, (d) a method can be considered in which a topsheet and an absorbent body are laminated together, and the antibacterial liquid is applied to a predetermined area of ​​the topsheet in the laminate using a spray device. In this case, the antibacterial liquid migrates from the topsheet to the superabsorbent polymer in the absorbent body, thereby forming an absorbent body having a superabsorbent polymer with the antibacterial liquid applied in a predetermined area.

[0044] The antibacterial agent is not particularly limited as long as it can be used in sanitary products. In this embodiment, the antibacterial agent includes a hydrophilic antibacterial agent. A hydrophilic antibacterial agent is an antibacterial agent that dissolves at least 40 g in 100 g of water at 25°C within 5 hours. The antibacterial agent is not particularly limited as long as it has hydrophilic properties and antibacterial function, i.e., the function of suppressing bacterial growth. Examples of the antibacterial agent include cationic antibacterial agents. Examples of cationic antibacterial agents include guanidine antibacterial agents, biguanide antibacterial agents, and quaternary ammonium salts. Examples of guanidine antibacterial agents include polyhexamethylene guanidine (PHMG). Examples of biguanide antibacterial agents include polyhexamethylene biguanide (PHMB), also known as polyaminopropyl biguanide. Examples of quaternary ammonium salts include benzalkonium chloride and benzethonium chloride. These antibacterial agents may be used alone or in combination.

[0045] The organic solvent is not particularly limited as long as it can be used in sanitary products and functions as a solvent for the antibacterial agent. In this embodiment, the organic solvent preferably contains a hydrophilic organic solvent, more preferably a non-volatile organic solvent. A hydrophilic organic solvent refers to an organic solvent that is miscible with water at any ratio. A non-volatile organic solvent refers to an organic solvent that has a vapor pressure of 50 Pa or less at 25°C. Examples of organic solvents include glycols and alcohols. Examples of glycols include propylene glycol (PG), dipropylene glycol (DPG), 1,3-butylene glycol (BG), and polyethylene glycol 400 (PEG 400). Examples of alcohols include 3-methoxy-3-methyl-1-butanol. These organic solvents may be used alone or in combination.

[0046] The lower limit of the total ratio of the antibacterial agent and organic solvent to the antibacterial solution is, for example, 90% by mass, preferably 95% by mass or more, from the viewpoint of ensuring antibacterial activity. In addition to the antibacterial agent and organic solvent, the antibacterial solution may further contain other solvents, such as water. The amount of water is preferably less than the amount of organic solvent, from the viewpoint of suppressing volatility of the antibacterial solution and suppressing rust on the manufacturing equipment. Furthermore, the lower limit of the ratio of the antibacterial agent to the total ratio of the antibacterial agent and solvent (organic solvent + other solvent) is, for example, 1% by mass, preferably 2% by mass, from the viewpoint of ensuring antibacterial activity. The upper limit is, for example, 60% by mass, preferably 50% by mass, from the viewpoint of dissolving the antibacterial agent in the solvent. The solvent of the antibacterial solution can be identified and quantified using GC / MS (gas chromatography / mass spectrometry), and the antibacterial agent in the antibacterial solution can be identified and quantified using LC / MS (high-performance liquid chromatography / mass spectrometry).

[0047] In the light incontinence pad 1, a large amount of antibacterial liquid coats the superabsorbent polymer located in the central portion of the absorbent body 4 in the width direction W, and a small amount (preferably no coating) coats the superabsorbent polymer located on both sides of the central portion of the absorbent body 4 in the width direction W. Therefore, when bodily fluids are excreted in the central portion of the width direction W of the absorbent body 4 and come into contact with the antibacterial liquid that coats the superabsorbent polymer, the antibacterial agent in the antibacterial liquid can exhibit antibacterial properties.

[0048] In addition, because the superabsorbent polymer in the central portion in the width direction W of the absorbent body 4 is coated with the antibacterial liquid, the absorption rate of body fluids by the superabsorbent polymer in the central portion in the width direction W can be slowed. This suppresses absorption of body fluids by the superabsorbent polymer in the central portion in the width direction W, making it easier for the body fluid to diffuse to both sides in the width direction W of the central portion. In other words, the diffusibility of body fluids to both sides in the width direction W can be improved. The diffused body fluid can then be easily absorbed by the superabsorbent polymer located on both sides in the width direction W of the central portion that is less coated with the antibacterial liquid. This allows for wider use of the absorbent body 4 and suppresses side leakage of body fluids from the ends in the width direction W of the light incontinence pad 1.

[0049] In this way, the light incontinence pad 1, which comprises an antibacterial liquid and a highly absorbent polymer, can achieve both antibacterial performance and absorption performance.

[0050] Furthermore, when the antibacterial liquid further coats the superabsorbent polymer located in the central portion of the absorbent body 4 in the longitudinal direction L, but does not coat the superabsorbent polymer located on either side of the central portion in the longitudinal direction L, the same effect can be obtained in the longitudinal direction L as when the antibacterial liquid coats the superabsorbent polymer located in the central portion in the width direction W, but does not coat the superabsorbent polymer located on either side of the central portion in the width direction W.

[0051] In a preferred embodiment of the present invention, the absorbent body 4 has a two-layer structure. The absorbent body 4 having the two-layer structure will be specifically described below.

[0052] 3 and 4 are plan views showing examples of the configuration of the upper absorbent body 11 and the lower absorbent body 12 of the light incontinence pad 1 according to the embodiment. As shown in Fig. 2 to Fig. 4, the light incontinence pad 1 further includes, as the absorbent body 4, the upper absorbent body 11 and the lower absorbent body 12 that is located closer to the skin than the upper absorbent body 11 in the thickness direction T.

[0053] In this embodiment, the upper absorbent body 11 is a sheet-like absorbent layer having liquid absorption and liquid retention properties, and has a generally rectangular shape in plan view that is long in the longitudinal direction L. The upper absorbent body 11 is located on the topsheet 2 side. The upper absorbent body 11 has an absorbent core 11a containing a superabsorbent polymer, and a skin-side core wrap sheet 11b1 and a non-skin-side core wrap sheet 11b2 that contain (sandwich) the absorbent core 11a.

[0054] The material of the absorbent core 11a is not particularly limited as long as it contains the above-mentioned superabsorbent polymer, and may contain, for example, pulp fiber in addition to the superabsorbent polymer. The pulp fiber content is within the range of 0 to 90% by mass of the superabsorbent polymer. In this embodiment, the amount of superabsorbent polymer contained in the upper-layer absorbent body 11 is greater than the amount of superabsorbent polymer contained in the lower-layer absorbent body 12. In this embodiment, the absorbent core 11a is composed solely of superabsorbent polymer. An absorbent body having such an absorbent core with a superabsorbent polymer content of 90% by mass or more can also be called an SAP sheet.

[0055] The materials for the skin side core wrap sheet 11b1 and the non-skin side core wrap sheet 11b2 are not particularly limited as long as they are liquid-permeable sheets, and examples thereof include liquid-permeable nonwoven fabrics (including tissues) made of synthetic resin fibers or pulp fibers. Liquid-permeable nonwoven fabrics are as described above. The basis weight of the skin side core wrap sheet 11b1 and the non-skin side core wrap sheet 11b2 is, for example, 5 to 100 g / m ２ Examples include:

[0056] The superabsorbent polymer (and pulp fibers) of the absorbent core 11a is preferably fixed to at least one of the skin-side core wrap sheet 11b1 and the non-skin-side core wrap sheet 11b2 with a hot melt adhesive or the like (not shown). However, the superabsorbent polymer may be simply wrapped between the skin-side core wrap sheet 11b1 and the non-skin-side core wrap sheet 11b2 without being fixed. The basis weight of the absorbent core 11a is, for example, 50 to 400 g / m ２ Examples include:

[0057] In this embodiment, the lower absorbent body 12 is an absorbent layer having liquid absorption and liquid retention properties, and is a generally rectangular shape that is long in the longitudinal direction L in a plan view, with both end edges in the longitudinal direction L being arc-shaped and a central portion in the longitudinal direction L that is narrowed in the width direction W. The lower absorbent body 12 is located on the backsheet 3 side. The lower absorbent body 12 has an absorbent core 12a containing a superabsorbent polymer and pulp fibers, and a skin-side core wrap sheet 12b1 and a non-skin-side core wrap sheet 12b2 that contain (sandwich) the absorbent core 12a.

[0058] The material of the absorbent core 12a is not particularly limited as long as it contains the above-mentioned pulp fiber and / or superabsorbent polymer. The content of the superabsorbent polymer is within the range of 0 to 90% of the mass of the pulp fiber. In this embodiment, the amount of pulp fiber contained in the lower-layer absorbent body 12 is greater than the amount of pulp fiber contained in the upper-layer absorbent body 11. In this embodiment, the absorbent core 12a contains 30% of the mass of the pulp fiber.

[0059] The materials of the skin side core wrap sheet 12b1 and the non-skin side core wrap sheet 12b2 are the same as those of the skin side core wrap sheet 11b1 and the non-skin side core wrap sheet 11b2 of the upper absorbent body 11. The basis weight of the skin side core wrap sheet 12b1 and the non-skin side core wrap sheet 12b2 is, for example, 5 to 100 g / m ２ Examples include:

[0060] The superabsorbent polymer and pulp fibers of the absorbent core 12a are preferably fixed to at least one of the skin-side core wrap sheet 12b1 and the non-skin-side core wrap sheet 12b2 with a hot melt adhesive or the like (not shown). However, the superabsorbent polymer and pulp fibers may be simply wrapped between the skin-side core wrap sheet 12b1 and the non-skin-side core wrap sheet 12b2 without being fixed. The basis weight of the superabsorbent polymer is, for example, 0 to 600 g / m ２ The basis weight of the pulp fiber is, for example, 50 to 700 g / m ２ Examples include:

[0061] The upper absorbent body 11 and the topsheet 2 are joined together with an adhesive. The upper absorbent body 11 and the lower absorbent body 12 are joined together with an adhesive. The lower absorbent body 12 and the backsheet 3 are joined together with an adhesive. Examples of adhesives include hot melt adhesives.

[0062] In a preferred aspect of this embodiment, as described above, the light incontinence pad 1 further includes an upper absorbent body 11 and a lower absorbent body 12. In this case, at least in the upper absorbent body 11, the antibacterial liquid coats a large amount of the superabsorbent polymer located in the central portion in the width direction W. Furthermore, the antibacterial liquid coats a small amount of the superabsorbent polymer located on both sides of the central portion in the width direction W (preferably, no coating). In other words, the antibacterial liquid coats only the superabsorbent polymer located approximately in the central portion in the width direction W, and barely coats the outer portions. The central portion in the width direction W is as described above. The method for coating the superabsorbent polymer with the antibacterial liquid in the upper absorbent body 11 is the same as methods (a) to (d) for coating the superabsorbent polymer with the antibacterial liquid described above.

[0063] Furthermore, at least in the upper absorbent body 11, the antibacterial liquid may cover a large amount of the superabsorbent polymer located in the central portion in the longitudinal direction L. Furthermore, the antibacterial liquid may cover a small amount of the superabsorbent polymer located on both sides of the central portion in the longitudinal direction L. In other words, the antibacterial liquid may cover only the superabsorbent polymer located approximately in the central portion in the longitudinal direction L, and may barely cover the outer portions. The central portion in the longitudinal direction L is as described above.

[0064] In this way, the superabsorbent polymer in the central portion in the width direction W of the upper absorbent body 11 is coated with the antibacterial liquid. Therefore, when bodily fluids pass through the upper absorbent body 11, they come into contact with the antibacterial liquid that coats the superabsorbent polymer, and the antibacterial agent in the antibacterial liquid can exhibit antibacterial properties.

[0065] In addition, because the superabsorbent polymer in the central portion of the upper-layer absorbent body 11 is coated with antibacterial liquid, it is possible to inhibit the absorption of body fluids by the superabsorbent polymer in the central portion. This makes it easier for body fluids to transfer to the lower-layer absorbent body 12. In this case, because the antibacterial liquid transfers to the lower-layer absorbent body 12 little by little each time body fluids transfer to the lower-layer absorbent body 12, it is possible to increase the amount of antibacterial liquid in the lower-layer absorbent body 12. In other words, the antibacterial properties of the lower-layer absorbent body 12 can be increased according to the amount of body fluid.

[0066] Furthermore, not only in the first absorption of body fluids but also in the second and subsequent absorptions, the upper absorbent body 11 suppresses the absorption of body fluids by the highly absorbent polymer in the central part, thereby improving the rewetting properties of the light incontinence pad 1.

[0067] Furthermore, in the upper absorbent body 11, the superabsorbent polymer on both outer sides of the central portion in the width direction W that is not covered much with the antibacterial liquid, for example, on both end portions in the width direction W, generally maintains the original absorption performance of the superabsorbent polymer. Therefore, body fluids can be absorbed by the superabsorbent polymer on both end portions in the width direction W. This further reduces side leakage of body fluids.

[0068] Furthermore, if the antibacterial liquid coats a large amount of the superabsorbent polymer located in the central portion of the longitudinal direction L of the upper absorbent body 11 and coats a small amount of the superabsorbent polymer located on both sides of the central portion in the longitudinal direction L, the same effect can be obtained in the longitudinal direction L as in the case where the antibacterial liquid coats a large amount of the superabsorbent polymer located in the central portion in the width direction W and coats a small amount of the superabsorbent polymer located on both sides of the central portion in the width direction W.

[0069] In a preferred aspect of this embodiment, a portion of the antibacterial liquid is contained in the lower absorbent body 12. However, the amount of antibacterial liquid contained in the upper absorbent body 11 is greater than the amount of antibacterial liquid contained in the lower absorbent body 12. The amount of antibacterial liquid in the lower absorbent body 12 may be 0 (zero).

[0070] However, the antibacterial liquid contained in the lower absorbent body 12 may be one that has been applied to the lower absorbent body 12 or one that has migrated from the upper absorbent body 11 .

[0071] The method for applying the antibacterial liquid to the lower-layer absorbent body is not particularly limited, and any method can be used. For example, when the absorbent material of the lower-layer absorbent body is pulp fiber and / or a superabsorbent polymer, methods (a) to (c) of coating the superabsorbent polymer with the antibacterial liquid can be used, with the superabsorbent polymer being pulp fiber and / or a superabsorbent polymer. Alternatively, methods (e) can be used in which an upper-layer absorbent body and a lower-layer absorbent body are stacked together, and the antibacterial liquid is applied to a predetermined region of the upper-layer absorbent body in the stack, or an upper-layer absorbent body with the antibacterial liquid applied to a predetermined region is stacked on the lower-layer absorbent body. In this case, the antibacterial liquid migrates from the upper-layer absorbent body to the pulp fiber and / or superabsorbent polymer of the lower-layer absorbent body, thereby forming a lower-layer absorbent body having pulp fiber and / or superabsorbent polymer coated with the antibacterial liquid in a predetermined region.

[0072] In this way, in the light incontinence pad 1, a portion of the antibacterial liquid is contained in the lower absorbent body 12, and the amount of antibacterial liquid in the upper absorbent body 11 is greater than the amount of antibacterial liquid in the lower absorbent body 12. As a result, a small amount of antibacterial liquid is also present in the lower absorbent body 12, allowing the antibacterial properties to be efficiently exhibited from the first absorption of bodily fluids.

[0073] In a preferred aspect of this embodiment, at least the lower absorbent body 12 of the upper absorbent body 11 and the lower absorbent body 12 contains pulp fibers. The amount of pulp fibers contained in the lower absorbent body 12 is greater than the amount of pulp fibers contained in the upper absorbent body 11. As a result, the upper absorbent body 11 has fewer pulp fibers that easily retain body fluids around the antibacterial agent (superabsorbent polymer), allowing the antibacterial effect of the antibacterial agent in the upper absorbent body 11 to be sustained. On the other hand, the lower absorbent body 12 has more pulp fibers, allowing it to quickly absorb and retain body fluids more easily. In this case, the lower absorbent body 12, which is physically separated from the body, can retain body fluids, thereby preventing skin rashes.

[0074] Next, the upper absorbent body 11 and the lower absorbent body 12 will be further described with reference to Figures 2 and 3-4. In the upper absorbent body 11, as shown in Figure 3, the area formed between the skin-side core wrap sheet 11b1 and the non-skin-side core wrap sheet 11b2 is divided into multiple placement areas PEA (21, 22) in a planar view by several bonding areas NPA (31, 32, 32'). However, the bonding area NPA is an area formed by bonding a portion of the skin-side core wrap sheet 11b1 and a portion of the opposing non-skin-side core wrap sheet 11b2 by squeezing them in the thickness direction T (e.g., embossing) or by pressing them together with an adhesive (e.g., hot melt adhesive). The placement area PEA is an area formed by another portion of the skin-side core wrap sheet 11b1 and another portion of the opposing non-skin-side core wrap sheet 11b2. An absorbent material (at least a superabsorbent polymer selected from superabsorbent polymers and pulp fibers) is placed in the placement area PEA. Therefore, the placement areas PEA (21, 22) can be referred to as superabsorbent polymer-present areas where superabsorbent polymer is present, while the bonding areas NPA (31, 32, 32') can be referred to as superabsorbent polymer-absent areas where superabsorbent polymer is not present.

[0075] In this embodiment, the upper absorbent body 11 is partitioned in the width direction W into three arrangement areas PEA by a pair of joining areas NPA, and these three arrangement areas PEA are sealed at the front and rear in the longitudinal direction L by other joining areas NPA. The three arrangement areas and PEA are an arrangement area 21 located in the center of the width direction W and extending in the longitudinal direction L, and a pair of arrangement areas 22 located at both ends of the arrangement area 21 in the width direction W and extending in the longitudinal direction L. The pair of joining areas NPA are strip-shaped joining areas 31 extending in the longitudinal direction L and arranged at a predetermined interval on both sides of the longitudinal center line CL in the width direction W. The other joining areas NPA are strip-shaped joining areas 32 (front side) and 32' (rear side) extending in the width direction W and arranged at a predetermined interval on both sides of the width center line CW in the longitudinal direction L. The pattern of the pair of bonding regions 31 is, for example, a band-like pattern formed such that the distance between them is narrow near the center in the longitudinal direction L and widens toward both sides in the longitudinal direction L. The pattern is formed along the pattern of the pair of compression portions 5 described below and is wider than that pattern.

[0076] Therefore, in this embodiment, the skin-side core wrap sheet 11b1, the non-skin-side core wrap sheet 11b2, the pair of bonding regions 31, and the other bonding regions 32 (front side) and 32' (rear side) form the placement region 21 and the pair of placement regions 22. The placement region 21 is long in the longitudinal direction L and has a generally hourglass shape with the central portion in the longitudinal direction L narrowed in the width direction W. The placement region 22 has a generally rectangular shape long in the longitudinal direction L, with one inner side in the width direction W being a convex curve relative to the longitudinal centerline CL. In this embodiment, the pair of bonding regions 31 and the other bonding regions 32 (front side) and 32' (rear side) are high-density areas that have a higher fiber density than the surrounding areas due to compression. Note that the shapes of the pair of bonding regions 31 and the other bonding regions 32 (front side) and 32' (rear side), i.e., the shapes of the placement region 21 and the pair of placement regions 22, are arbitrary.

[0077] In the present embodiment, the superabsorbent polymer located in the central portion in the width direction W can be the superabsorbent polymer located in the arrangement region 21, and the superabsorbent polymer located on both outer sides of the central portion in the width direction W can be the superabsorbent polymer located in the pair of arrangement regions 22. In this case, the antibacterial liquid coats a large amount of the superabsorbent polymer located in the arrangement region 21, but coats a small amount of the superabsorbent polymer located in the pair of arrangement regions 22 (preferably, the coating amount is zero (not coated)).

[0078] In this case, body fluids are excreted near the placement region 21 and come into contact with the antibacterial liquid coating the superabsorbent polymer, allowing the antibacterial agent in the antibacterial liquid to exhibit antibacterial properties. Additionally, because the superabsorbent polymer in the placement region 21 is coated with the antibacterial liquid, the absorption rate of the body fluid by the superabsorbent polymer in the placement region 21 can be slowed. This suppresses absorption of body fluids by the superabsorbent polymer in the placement region 21, facilitating diffusion of the body fluid to both sides in the width direction W of the central portion. In other words, the diffusion of body fluids to both sides in the width direction W can be improved. The diffused body fluid can then be easily absorbed by the superabsorbent polymer located in the pair of placement regions 22, which is less coated with the antibacterial liquid. This allows for wider use of the upper-layer absorbent body 11 and suppresses side leakage of body fluids from the ends of the light incontinence pad 1 in the width direction W.

[0079] In this embodiment, as shown in FIG. 4 , the lower absorbent body 12 has a space formed between the skin-side core wrap sheet 12b1 and the non-skin-side core wrap sheet 12b2 filled with the absorbent polymer and pulp fibers of the absorbent core 12a. The lower absorbent body 12 has a thick region 12m having a generally rectangular shape with rounded corners at the center in the width direction W and the longitudinal direction L, a medium-thickness region having a generally annular shape surrounding the thick region 12m, and a thin region having a generally annular shape and the outer shape of the lower absorbent body 12. The thick region 12m has the thickest thickness in the thickness direction T, the thin region has the thinnest thickness in the thickness direction T, and the medium region has a thickness between the thin region and the thick region 12m. Therefore, the lower absorbent body 12 has a centrally-heavy structure (e.g., a high volume in the center). In this embodiment, the thick region 12m generally corresponds to the central region TA in a plan view.

[0080] In this embodiment, the light incontinence pad 1 includes a pair of compressed portions 5 extending in the longitudinal direction L and arranged at a predetermined interval in the width direction W. The compressed portions 5 are formed by compressing (e.g., embossing) the topsheet 2 and the upper and lower absorbent bodies 11 and 12 in the thickness direction T. The compressed portions 5 extend from the topsheet 2 through the upper absorbent body 11 and into the lower absorbent body 12 in the thickness direction T. A high-density portion having a higher fiber density than the surrounding area is formed in the lower portion (non-skin-facing portion) of the bottom of the compressed portion 5 by compression. The compressed portions 5 may extend from the surface of the topsheet 2 to the skin-facing surface of the backsheet 3 in the thickness direction T. The width of the compressed portions 5 is, for example, 1 to 5 mm. The pattern of the pair of compressed portions 5 is not particularly limited, and any known pattern used in absorbent articles may be adopted. In this embodiment, the distance between the pair of compressed portions 5 is small (narrow) near the center in the longitudinal direction L, becomes larger (wider) toward both outer sides in the longitudinal direction L, and then becomes smaller (narrower) again toward both ends of the lower absorbent body 12. This pattern makes it easier to diffuse excrement moving in the longitudinal direction L along the pair of compressed portions 5 in both the width direction W and the longitudinal direction L.

[0081] In this embodiment, the light incontinence pad 1 further includes compression sections 6 on the front and rear sides in the longitudinal direction L, each extending in the width direction W and arranged at a predetermined interval in the longitudinal direction L. The compression sections 6 have the same structure as the compression sections 5. The compression sections 6 are arranged between the pair of compression sections 5 in the vicinity of both ends in the longitudinal direction L of the pair of compression sections 5, in the shape of an arc that convex outward.

[0082] One and the other of the pair of compressed portions 5 are located within one and the other of the pair of joining regions 31, respectively, in the width direction W. Furthermore, one and the other of the pair of compressed portions 5 are spaced apart from the central arrangement region 21 and the pair of arrangement regions 22 in the width direction W.

[0083] Thus, in the light incontinence pad 1, the upper absorbent body 11 has, in plan view, a superabsorbent polymer-containing region, i.e., the placement region PEA (21, 22), and a superabsorbent polymer-free region, i.e., the joining region NPA (31, 32, 32'). The superabsorbent polymer-free region (joining region NPA) has compressed sections 5. Therefore, bodily fluids can migrate from the upper absorbent body 11 to the lower absorbent body 12 via the compressed sections 5 without being inhibited by the superabsorbent polymer in the placement region PEA (21, 22), thereby enhancing fluid migration from the upper absorbent body 11 to the lower absorbent body 12. This further suppresses side leakage of bodily fluids.

[0084] In a preferred aspect of this embodiment, the antibacterial liquid coats a large amount of superabsorbent polymer located in the central portion of the upper absorbent body 11 (absorbent body 4) in the longitudinal direction L. However, the antibacterial liquid coats a small amount of superabsorbent polymer located in front (ventral side) of the central portion of the upper absorbent body 11 (absorbent body 4) in the longitudinal direction L. In other words, the antibacterial liquid coats only the superabsorbent polymer located in the approximately central portion of the superabsorbent polymer in the upper absorbent body 11 (absorbent body 4) in the longitudinal direction L, or the superabsorbent polymer located in the central portion and rear (dorsal side), and hardly coats the outer portions. Note that it is sufficient that at least a portion of the antibacterial liquid is contained in the upper absorbent body 11, and that at least a portion of the antibacterial liquid contained in the upper absorbent body 11 coats a predetermined superabsorbent polymer. In other words, it is not necessary for the antibacterial agent to coat the superabsorbent polymer entirely.

[0085] In this way, in the light incontinence pad 1, a large amount of antibacterial liquid coats the superabsorbent polymer located in the central portion of the upper absorbent body 11 (absorbent body 4) in the longitudinal direction L, and a small amount (preferably no coating) coats the superabsorbent polymer located more forward (ventral side) than the central portion of the upper absorbent body 11 (absorbent body 4) in the longitudinal direction L. This suppresses absorption of body fluids by the superabsorbent polymer in the central portion in the longitudinal direction L, and makes it easier for the superabsorbent polymer on the ventral side of the central portion in the longitudinal direction L, which is less coated with antibacterial liquid and therefore has a relatively slow absorption rate, to absorb body fluids.

[0086] Furthermore, since the antibacterial liquid is not present in the upper absorbent body 11 (absorbent body 4) in the abdominal area (front longitudinal portion) of the body, where the upper absorbent body 11 (absorbent body 4) is likely to come into direct or indirect surface contact, contact between the antibacterial liquid and the body can be suppressed, thereby preventing the antibacterial agent contained in the antibacterial liquid from irritating the skin.

[0087] In a preferred aspect of this embodiment, the upper absorbent body 11 has a skin-side portion 51 located on the skin side in the thickness direction T, and a non-skin-side portion 52 located on the non-skin side of the skin-side portion in the thickness direction T. The water retention rate of the skin-side portion 51 is lower than the water retention rate of the non-skin-side portion 52.

[0088] Here, one method for reducing the water retention rate of the skin side portion 51 of the upper absorbent body 11 is to apply antibacterial liquid with a spray device from the skin side of the upper absorbent body 11. Another method is to apply antibacterial liquid with a spray device from the side of the topsheet 2 to a laminate of the topsheet 2 and absorbent body 4, and transfer the antibacterial liquid to the skin side of the upper absorbent body 11 via the topsheet 2. As a result, more antibacterial liquid is applied to the superabsorbent polymer of the skin side portion 51 than to the non-skin side portion 52, and the water retention rate of the superabsorbent polymer of the skin side portion 51 is reduced.

[0089] As described above, in the light incontinence pad 1, the skin-side portion 51 of the upper absorbent body 11 has a relatively low water retention rate. This allows the skin-side portion 51, which is the front side of the upper absorbent body 11, to be kept suitably dry (smooth). On the other hand, the non-skin-side portion 52 of the upper absorbent body 11 has a relatively high water retention rate. This allows the non-skin-side portion 52, which is the back side of the upper absorbent body 11, to come into sufficient contact with the superabsorbent polymer coated with the antibacterial agent and body fluids. This enhances the antibacterial performance of the antibacterial agent.

[0090] In a preferred aspect of this embodiment, the skin-side core wrap sheet 12b1 and the non-skin-side core wrap sheet 12b2 of the lower absorbent body 12 are made of crepe paper. Crepe paper is a creped nonwoven fabric (including paper) made of synthetic resin fibers, pulp fibers, or the like, and has an uneven structure with concave and convex portions formed by multiple wrinkles. The degree of unevenness of the skin-side core wrap sheet 12b1 is smaller than the degree of unevenness of the non-skin-side core wrap sheet 12b2. Here, the "degree of unevenness" refers to the number of concave and convex portions (wrinkles) per unit length in a direction (e.g., width direction W) perpendicular to the direction in which the concave and convex portions (wrinkles) extend (e.g., longitudinal direction L). The "size of the concave and convex portions" refers to the height and / or width of the concave and convex portions. The height of the concave and convex portions refers to the height from the bottom of the concave and convex portions (the portion between adjacent convex portions) to the top of the convex portion. The width of the irregularities refers to the distance between the tops of adjacent convex portions or the distance between the bottoms of adjacent concave portions. A small degree of irregularity refers to a small number of irregularities, a small height of the irregularities, and / or a large width of the irregularities, but does not include cases where there are no irregularities. This is to maintain a certain degree of ease of deformation on the skin side of the absorbent body 4.

[0091] The degree of unevenness of the crepe paper can be adjusted by creping conditions, applying a liquid to the crepe paper, etc. For example, when a liquid (e.g., an antibacterial liquid) is applied to the crepe paper, the applied portion becomes soft as it is soaked in the liquid, and the unevenness is easily reduced. This reduces the degree of unevenness. In this case, from the viewpoint of easily maintaining affinity with body fluids and the degree of unevenness, a hydrophilic and non-volatile liquid is preferably used as the liquid applied to the crepe paper.

[0092] In this embodiment, the degree of unevenness does not need to be smaller across the entire surface of the skin-side core wrap sheet 12b1 than that of the non-skin-side core wrap sheet 12b2. Examples of areas with a small degree of unevenness include, in a plan view, a central portion (equivalent to one unit) excluding both end portions (equivalent to one unit each) when the skin-side core wrap sheet 12b1 is divided into thirds in the width direction W, a central portion (equivalent to two units) excluding both end portions (equivalent to one unit each) when the skin-side core wrap sheet 12b1 is divided into fourths in the width direction W, and a central portion (equivalent to three or one unit) excluding both end portions (equivalent to one or two units each) when the width direction W is divided into fifths. And / or, examples of the portion with a small degree of unevenness include, for example, the central portion (one portion) excluding both end portions (one portion each) when the skin-side core wrap sheet 12b1 is divided into thirds in the longitudinal direction L, the central portion (two portions) excluding both end portions (one portion each) when the skin-side core wrap sheet 12b1 is divided into fourths in the longitudinal direction L, the central portion (three or one portion) excluding both end portions (one or two portions each) when the skin-side core wrap sheet 12b1 is divided into fifths in the longitudinal direction L, and portions shifted 10 to 30% forward in the longitudinal direction L. However, these boundaries may be shifted slightly (by about ±20%). In any of the above cases, the portion with a small degree of unevenness preferably includes the excretory opening contact region in a plan view, and is preferably the region overlapping with the absorbent core 12a.

[0093] In this embodiment, the skin-side core wrap sheet 12b1 and the non-skin-side core wrap sheet 12b2 encase the absorbent core 12a so that the unevenness and wrinkles of the crepe paper extend along the longitudinal direction L. However, each of the skin-side core wrap sheet 12b1 and the non-skin-side core wrap sheet 12b2 does not need to have unevenness or wrinkles over its entire surface. It is sufficient that each of the skin-side core wrap sheet 12b1 and the non-skin-side core wrap sheet 12b2 has unevenness or wrinkles over 90% or more of its entire surface, including the excretory opening contact area, preferably 95% or more, and more preferably 98% or more. This makes it easier to prevent each of the skin-side core wrap sheet 12b1 and the non-skin-side core wrap sheet 12b2 from breaking due to external force.

[0094] In this embodiment, in the skin-side core wrap sheet 12b1, the average number of irregularities (wrinkles) extending along the longitudinal direction L per unit length of 1 cm in the width direction W is, for example, 1 to 50. In the skin-side core wrap sheet 12b1, the average height of the irregularities, which is the size of the irregularities (wrinkles), is, for example, 0.1 to 1 mm. The average width of the irregularities, which is the size of the irregularities, is, for example, 0.2 to 10 mm. On the other hand, in the non-skin-side core wrap sheet 12b2, the average number of irregularities (wrinkles) extending along the longitudinal direction L per unit length of 1 cm in the width direction W is, for example, 2 to 100. In the non-skin-side core wrap sheet 12b2, the average height of the irregularities, which is the size of the irregularities (wrinkles), is, for example, 0.2 to 2 mm. The average width of the irregularities, which is the size of the irregularities, is, for example, 0.1 to 5 mm.

[0095] In this way, in the light incontinence pad 1, the degree of unevenness of the skin-side core wrap sheet 12b1 made of uneven crepe paper is relatively small in the lower absorbent body 12. This improves the liquid diffusion in the planar direction of the skin-side core wrap sheet 12b1.

[0096] At the same time, the contact area between the upper absorbent body 11 and the skin-side core wrap sheet 12b1 can be increased, and the contact area between the skin-side core wrap sheet 12b1 and the absorbent core 12a can be increased. As a result, during use, bodily fluid released into the light incontinence pad 1 and transferred from the upper absorbent body 11 to the skin-side core wrap sheet 12b1 can be diffused in the planar direction of the skin-side core wrap sheet 12b1 and then transferred to the absorbent core.

[0097] On the other hand, by relatively increasing the unevenness of the non-skin-side core wrap sheet 12b2 made of crepe paper, the non-skin-side core wrap sheet 12b2 can be made more deformable. As a result, even if the light incontinence pad 1 expands and contracts due to the user's body movements during use, the non-skin-side core wrap sheet 12b2 can follow the expansion and contraction and prevent breakage. In this case, the unevenness of the non-skin-side core wrap sheet 12b2 absorbs the external force caused by the body movements, reducing the external force acting on the skin-side core wrap sheet 12b1 and preventing breakage of the skin-side core wrap sheet 12b1.

[0098] In a preferred aspect of this embodiment, the topsheet 2 contains a hydrophilizing agent, and the viscosity of the antibacterial liquid is higher than the viscosity of the hydrophilizing agent.

[0099] However, the topsheet 2 is formed, for example, by treating the material that constitutes the topsheet 2 with a hydrophilizing agent known in the art (e.g., by coating the material with a hydrophilizing agent or by kneading the hydrophilizing agent into the material). There are no particular limitations on the hydrophilizing agent as long as it is used in absorbent articles, and examples of the hydrophilizing agent include alkyl phosphate ester salts and alkyl phosphate metal salts. Alternatively, examples of the hydrophilizing agent include a mixture of an alkyl phosphate ester salt having 10 to 30 carbon atoms with a betaine compound, sulfate ester salt, or sulfonate salt having 10 to 30 carbon atoms, and a mixture of an alkyl phosphate ester salt and polyether-modified silicone.

[0100] Thus, in the light incontinence pad 1, the viscosity of the antibacterial liquid in the absorbent body 4 is higher than the viscosity of the hydrophilizing agent in the topsheet 2. Therefore, compared to the hydrophilizing agent, which is easily washed away by body fluids, the antibacterial liquid is less likely to be washed away by body fluids, so even if body fluids are excreted into the light incontinence pad 1 multiple times, the antibacterial liquid can easily maintain a state in which it coats the superabsorbent polymer, thereby increasing the durability of the antibacterial agent's effectiveness.

[0101] <Method for Measuring the Irregularity of the Core Wrap> The irregularity of the core wrap is measured as follows. (1) Divide the absorbent article into thirds in both the width and length directions to prepare nine samples. (2) After freezing each sample using liquid nitrogen, cut the sample in the thickness direction with a sharp utility knife so as not to distort the irregularity, allowing for a cross-sectional view of the desired irregularity measurement points (e.g., the center portions in the length and width directions, and the front-to-back portions in the length direction). The cut size may be 1 cm x 1 cm. (3) Prepare a microscope or optical microscope (e.g., VHX-7000 manufactured by Keyence Corporation) and capture an image of the cross section of the core wrap sheet at a magnification of 10 to 100 times. (4) In the captured image of each sample, measure the number of irregularities (wrinkles) per unit length and / or the height and / or width of the irregularities for each of the concave and convex portions. (5) The final number of irregularities (wrinkles) per unit length and / or the height and / or width of the irregularities are determined by calculating the average of the measurement values ​​for nine samples (however, if there is a large difference depending on the location (±30% or more), at least three nearby samples).

[0102] <Method for measuring the area where antibacterial liquid (including antibacterial agent) has been applied> The method for measuring the amount of antibacterial liquid in the area where antibacterial liquid (including antibacterial agent) has been applied is as follows. (1) A sample of a predetermined size (e.g., 1 cm x 1 cm) is cut out from the part of the absorbent article where it is desired to check whether or not antibacterial liquid has been applied. (2) The antibacterial agent in the sample is identified and quantified using LC / MS (high performance liquid chromatography mass spectrometry). (3) Steps (1) to (2) above are performed on three samples, and the average value is calculated to determine the presence and amount of antibacterial liquid in that area. (4) Steps (1) to (3) above are performed on multiple parts of the absorbent article, and the areas where antibacterial liquid has been applied and the amount of antibacterial liquid in those areas are determined.

[0103] <Method for measuring viscosity of antibacterial liquid or hydrophilizing agent> When a sufficient amount of antibacterial liquid or hydrophilizing agent is to be measured, the viscosity of the antibacterial liquid or hydrophilizing agent is measured as follows. (1) Prepare the following equipment: HAAKE RheoStress 1 (sensor: cone φ60 mm, 1° angle C60 / 1) manufactured by Thermo Fisher Scientific Co., Ltd. (2) Place 38 ml of the antibacterial liquid or hydrophilizing agent to be measured in a container attached to the equipment, and immerse the measuring element in the antibacterial liquid. (3) Measure the viscosity under the following conditions: temperature 25°C, humidity 50%, shear rate: 10.0 (l / s).

[0104] <Method for Measuring the Water Retention Rate of Superabsorbent Polymer> The method for measuring the water retention rate of the superabsorbent polymer in the upper absorbent body is as follows. (1) In the upper absorbent body of an absorbent article, the skin-side core wrap sheet to which the superabsorbent polymer is adhered and the non-skin-side core wrap sheet to which the superabsorbent polymer is adhered are peeled away from each other to separate the skin-side and non-skin-side portions of the upper absorbent body. (2) Other sheets and adhesives adhered to the skin-side core wrap sheet are removed with an organic solvent that is not absorbed by the superabsorbent polymer, and other sheets and adhesives adhered to the non-skin-side core wrap sheet are removed with an organic solvent that is not absorbed by the superabsorbent polymer, and the superabsorbent polymer in the skin-side and non-skin-side portions is separately removed. (3) 1.000 g of the removed superabsorbent polymer in the skin-side and non-skin-side portions is accurately weighed separately on an electronic balance (sensitivity 0.001 g). If the amount of superabsorbent polymer is insufficient, the superabsorbent polymer is removed from multiple upper absorbents in multiple absorbent articles in the same package, or from multiple upper absorbents in multiple absorbent articles packed in the same cardboard box. (4) The measured amounts of superabsorbent polymer for the skin-side and non-skin-side portions are placed in separate nylon net bags, and the nylon net bags are heat-sealed. The nylon net bags are 10 cm square bags made of nylon net (250 mesh nylon net (N-NO. 250HD: manufactured by NBC Meshtec Co., Ltd.)). The following steps are carried out for each bag. (5) The mass of the bag containing the sample from (4) is measured using an electronic balance. The measured value is referred to as mass A. (6) 1000 ml of saline is placed in a 2 L beaker. The saline is a 0.9% aqueous sodium chloride solution. (7) The bag is immersed in the 2 L beaker from (6) so that it touches the bottom. (8) Fix one side of the top of the bag to the open edge of a 2L beaker with clothespins and leave for 1 hour. At this time, try to avoid contact between the superabsorbent polymer and the nylon net as much as possible. (9) After leaving, pull out the bag and pinch the center of the short side of the bag (5 mm from the top edge and 50 mm from both ends) with clothespins and drain for 15 minutes. (10) Measure the mass of the bag after draining with an electronic balance. The measured value is mass B.(11) After draining the water, the bag is dehydrated in a centrifuge (Model H130: manufactured by Kokusan Centrifuge Co., Ltd.). However, the conditions are a rotation speed of 850 rpm (150 G), and a time of 90 seconds after stabilizing at 850 rpm. (12) The mass of the bag after dehydration is measured using an electronic balance. The measured value is called mass C. (13) The water retention rate is calculated using the following formula: Water retention rate = C / B (g / g) The water absorption rate is calculated using the following formula: Water absorption rate = B / A (g / g) (14) Five tests are conducted, and the average is finally used as the water retention rate of each superabsorbent polymer.

[0105] The present invention will be described below based on examples, but the present invention is not limited to these examples.

[0106] (1) Samples (a) Example 1 A sample was prepared in which the superabsorbent polymer in the widthwise center portion of the upper absorbent body (divided into three sections by the outer width sections and the widthwise center portion) of a Lifree Refreshing Pad 20cc manufactured by Unicharm Corporation (which has the same basic structure as the above-mentioned Light Incontinence Pad 1) was replaced with antibacterial coating SAP1. Antibacterial coating SAP1 was prepared by dissolving the superabsorbent polymer in 0.3 ml of 1,3-butylene glycol (BG) containing 2% by weight of the antibacterial agent polyhexamethylene biguanide (PHMB), and air-drying for 24 hours. (b) Example 2 A sample was prepared in which the superabsorbent polymer in the widthwise center portion of the upper absorbent body of a Lifree Refreshing Pad 20cc was replaced with antibacterial coating SAP2. The antibacterial coating SAP2 was prepared by dissolving the superabsorbent polymer in 0.3 ml of propylene glycol (PG) containing 2% by mass of the antibacterial agent benzalkonium chloride, and then air-drying for 24 hours. (c) Comparative Example A sample was prepared in which the superabsorbent polymer in the widthwise center and both widthwise outer portions of the upper absorbent body of a Lifree Refreshing Pad 20 cc was replaced with the antibacterial coating SAP2.

[0107] (2) Evaluation (i) Each sample of Example 1, Example 2, and Comparative Example was stretched out to a wrinkle-free state and attached to a glass plate with tape. (ii) Each sample was maintained with the glass plate tilted 30 degrees across the width from the horizontal. (iii) 10 ml of artificial urine was added three times every minute to the center of each sample in the longitudinal and width directions using a burette. The artificial urine was prepared by dissolving 200 g of urea, 80 g of sodium chloride (salt), 8 g of magnesium sulfate heptahydrate, 3 g of calcium chloride dihydrate, and 1 g of Blue No. 1 dye [65% Blue No. 1 / 35% sodium chloride] in 10 L of ion-exchanged water. (iv) For each sample, leakage of artificial urine from the widthwise edge (bottom) (side leakage) was confirmed.

[0108] (3) Results No side leakage occurred in the samples of Examples 1 and 2. However, side leakage occurred in the sample of Comparative Example. These results demonstrate that both antibacterial properties and side leakage prevention can be achieved by using a highly absorbent polymer coated with an antibacterial agent only in the center portion in the width direction.

[0109] The light incontinence pad of the present invention is not limited to the above-described embodiment, and can be modified as appropriate or publicly known techniques can be applied within the scope that does not deviate from the object and intent of the present invention.

[0110] 1 absorbent article 4 absorbent body

Claims

1. An absorbent article having a longitudinal direction, a width direction and a thickness direction which are perpendicular to each other, and comprising an absorbent body carrying a superabsorbent polymer, further comprising an antibacterial liquid containing an antibacterial agent and an organic solvent, wherein the antibacterial liquid coats a large amount of the superabsorbent polymer located in a central portion of the absorbent body in the width direction, and coats a small amount of the superabsorbent polymer located on both outsides of the central portion in the width direction of the absorbent body.

2. The absorbent article according to claim 1, further comprising: an upper-layer absorbent body including said absorbent; and a lower-layer absorbent body located closer to the non-skin-facing side in the thickness direction than said upper-layer absorbent body.

3. The absorbent article according to claim 2, wherein a portion of the antibacterial liquid is contained in the lower absorbent body, and the amount of the antibacterial liquid contained in the upper absorbent body is greater than the amount of the antibacterial liquid contained in the lower absorbent body.

4. An absorbent article as described in claim 2 or 3, wherein the upper absorbent body has, in a planar view, a superabsorbent polymer presence region in which the superabsorbent polymer is present, and a superabsorbent polymer non-presence region in which the superabsorbent polymer is not present, and the superabsorbent polymer non-presence region has a compressed portion in which the upper absorbent body is compressed in the thickness direction.

5. An absorbent article as described in any one of claims 2 to 4, wherein at least the lower absorbent of the upper absorbent and the lower absorbent contains pulp fibers, and the amount of the pulp fibers contained in the lower absorbent is greater than the amount of the pulp fibers contained in the upper absorbent.

6. An absorbent article as described in any one of claims 2 to 5, wherein the antibacterial liquid coats a greater amount of the superabsorbent polymer located in the longitudinal central portion of the absorbent body, and a smaller amount of the superabsorbent polymer located forward of the longitudinal central portion of the absorbent body.

7. An absorbent article as claimed in any one of claims 2 to 6, wherein the upper absorbent body has a skin side portion located on the skin side in the thickness direction, and a non-skin side portion located on the non-skin side of the skin side portion in the thickness direction, and the water retention rate of the skin side portion is lower than the water retention rate of the non-skin side portion.

8. An absorbent article as described in any one of claims 2 to 7, wherein the lower absorbent body includes an absorbent core, a skin-side core wrap sheet covering the skin-side of the absorbent core in the thickness direction, and a non-skin-side core wrap sheet covering the non-skin-side of the absorbent core in the thickness direction, wherein the skin-side core wrap sheet and the non-skin-side core wrap sheet are made of crepe paper having an unevenness, and the degree of unevenness of the skin-side core wrap sheet is smaller than the degree of unevenness of the non-skin-side core wrap sheet.

Images