Absorbent article and method of determining defecation and urination

Abstract

An absorbent article (1) has a liquid absorbent body (2), a liquid permeable sheet (3) arranged closer to a skin side than the absorbent body (2) in a thickness direction, and a liquid impermeable sheet (4) arranged closer to a non-skin side than the absorbent body (2) in the thickness direction. The absorbent article (1) has a skin side electrode (11) between the liquid permeable sheet (3) and the absorbent body (2), and a non-skin side electrode (12) between the liquid impermeable sheet (4) and the absorbent body (2).

Description

[0001] This application is a divisional application of an application with the application number 202180022381.1, the application date of April 26, 2021, and the application title of "Absorbent article and method of determining defecation and urination". TECHNICAL FIELD

[0002] The present application relates to an absorbent article and a method of determining defecation / urination. BACKGROUND

[0003] With respect to conventional disposable diapers and the like, an absorbent article having a discharge detection function for detecting discharge of urine and notifying a user thereof is known. For example, Patent Literature 1 discloses a technique of disposing a moisture sensor including a pair of electrodes on the inside of an absorbent body of a diaper, so that discharge of urine can be detected based on moisture making the electrodes conductive between them at the time of discharge of urine.

[0004] PRIOR ART DOCUMENTS

[0005] PATENT LITERATURE

[0006] Patent Literature 1: Japanese Patent Application Publication No. 2012-223386 SUMMARY

[0007] In recent years, in a situation where bedridden elderly people wear diapers in nursing facilities, from the viewpoint of reducing the burden on nursing staff, it is required that the presence / absence of discharge and whether the discharge is feces or urine can be accurately determined even in a state of wearing a diaper. However, in an absorbent article having a conventional discharge detection function such as Patent Literature 1, the presence / absence of discharge can be detected, but it is not possible to distinguish whether the discharge is feces or urine. Therefore, the nursing staff has the trouble of opening and checking the diaper every time of discharge.

[0008] The present application has been achieved in view of the conventional problems such as the above, and one aspect of the present application is to provide an absorbent article capable of accurately determining whether the discharge is feces or urine.

[0009] A main aspect of the present application for achieving the above aspect is an absorbent article having a longitudinal direction, a width direction, and a thickness direction intersecting each other in a stretched state, the absorbent article including: a liquid-absorbing absorbent; a liquid-permeable sheet disposed on a skin side in the thickness direction with respect to the absorbent; a liquid-impermeable sheet disposed on a non-skin side in the thickness direction with respect to the absorbent; a skin-side electrode between the liquid-permeable sheet and the absorbent; and a non-skin-side electrode between the liquid-impermeable sheet and the absorbent.

[0010] Features of the present application other than the above will become apparent by reading the description of the specification with reference to the attached drawings.

[0011] According to the present application, it is possible to provide an absorbent article capable of accurately determining whether excreta is feces or urine. BRIEF DESCRIPTION OF DRAWINGS

[0012] [ Figure 1 ] Figure 1 A is a schematic plan view showing an unfolded state of the diaper 101. Figure 1 B is a schematic cross-sectional view showing a cross section taken along Figure 1 A in line X-X.

[0013] [ Figure 2 ] is a schematic plan view of the absorbent pad 1.

[0014] [ Figure 3 ] is a schematic cross-sectional view showing a cross section taken along Figure 2 in line A-A.

[0015] [ Figure 4 ] is a schematic plan view and cross-sectional view showing an example of the configuration of a pair of skin-side electrodes 11 and 11.

[0016] [ Figure 5 ] is a conceptual view of an excreta detection circuit using the absorbent pad 1.

[0017] [ Figure 6 ] Figure 6 A and Figure 6 B are views showing the principle of detecting urine when urine is excreted.

[0018] [ Figure 7 ] Figure 7 A and Figure 7 B are views showing the principle of detecting feces when feces are excreted.

[0019] [ Figure 8 ] is a flowchart showing an example of a defecation / urination determination process using the absorbent pad 1.

[0020] [ Figure 9 ] is a flowchart showing a defecation / urination determination process using the absorbent pad 1 in the second embodiment. DETAILED DESCRIPTION

[0021] The following matters will become clear through the description of this specification and the drawings.

[0022] An absorbent article having longitudinal, width, and thickness directions intersecting each other in an extended state, the absorbent article including: a liquid-absorbing absorbent; a liquid-permeable sheet disposed on a skin side in the thickness direction with respect to the absorbent; a liquid-impermeable sheet disposed on a non-skin side in the thickness direction with respect to the absorbent; a skin-side electrode between the liquid-permeable sheet and the absorbent; and a non-skin-side electrode between the liquid-impermeable sheet and the absorbent.

[0023] According to the above-described absorbent article, changes in a predetermined time period between a skin-side capacitance value detected by the skin-side electrode and a non-skin-side capacitance value detected by the non-skin-side electrode can be measured. Since the changes in the skin-side capacitance value and the non-skin-side capacitance value are expressed differently during urination and during defecation, monitoring the expression of these changes makes it possible to accurately determine whether the excretion is feces or urine.

[0024] In such an absorbent article, it is desirable that at least one pair of the non-skin-side electrodes be disposed to be spaced apart from each other in the width direction at a predetermined distance.

[0025] According to the above-described absorbent article, when moisture such as urine adheres to the portion between a pair of non-skin-side electrodes spaced apart from each other in the width direction, conduction between the electrodes is established, and this changes the capacitance value and the resistance value detected between the electrodes. By measuring the amount of this change, it is possible to accurately determine the excretion of urine or feces.

[0026] In such an absorbent article, it is desirable that at least one pair of the non-skin-side electrodes be disposed to be spaced apart from each other in the width direction at a predetermined distance.

[0027] According to the above-described absorbent article, similar to the non-skin-side electrodes, by measuring the amount of change in the capacitance value and the resistance value, it is possible to accurately determine the excretion of urine or feces. Furthermore, the skin-side electrodes and the non-skin-side electrodes are disposed at positions offset from each other along the width direction, and this makes it easier to perform work for connecting a detection device or the like to each electrode.

[0028] In such an absorbent article, it is desirable that the spacing between a pair of the skin-side electrodes in the width direction be greater than the spacing between a pair of the non-skin-side electrodes in the width direction.

[0029] According to the above-described absorbent article, the spacing between the skin-side electrodes, to which urine easily reaches, is greater, and thus it is possible to relatively suppress an increase in capacitance and a decrease in resistance with respect to the non-skin-side electrodes. This makes it possible to suppress a situation in which a determination based on a combination of changes on the skin surface side and the non-skin surface side cannot be used due to previously exceeding the limit value of the skin-side electrodes.

[0030] In the absorbent article, it is desirable that a distance between the pair of the skin-side electrodes in the width direction be 40 mm or more.

[0031] According to the above-described absorbent article, the distance between the skin-side electrodes in the width direction is not too narrow, and thus, for example, when a diaper is applied to a narrow crotch, this suppresses generation of noise resulting from contact between the electrodes. This makes it possible to suppress occurrence of false detection. Furthermore, it is possible to more easily appropriately adjust upper and lower limits of the capacitance value and the resistance value detected between the electrodes.

[0032] In the absorbent article, it is desirable that a distance between the pair of the non-skin-side electrodes in the width direction be 40 mm or more.

[0033] According to the above-described absorbent article, the distance between the non-skin-side electrodes in the width direction is not too narrow, and thus this suppresses generation of noise during use. This makes it possible to suppress occurrence of false detection. Furthermore, it is possible to more easily appropriately adjust upper and lower limits of the capacitance value and the resistance value detected between the electrodes.

[0034] In the absorbent article, it is desirable that presence / absence of excretion be detected based on contact of each of the skin-side electrodes and the non-skin-side electrodes with excretion.

[0035] According to the above-described absorbent article, direct contact between the excretion and the electrodes makes it possible to promote flow of electric current through moisture contained in the excretion between the electrodes. Thus, compared with a case where the excretion and the electrodes do not contact each other, a change in the capacitance value or the resistance value detected between the electrodes becomes clear, and it is possible to more accurately determine the excretion.

[0036] In the absorbent article, it is desirable that the skin-side electrodes and the non-skin-side electrodes each include: an electrically conductive portion; and a liquid-impermeable sheet member configured to be stacked on the electrically conductive portion in the thickness direction.

[0037] According to the above-described absorbent article, on one side in the thickness direction of the electrically conductive portion, contact between the electrically conductive portion and the excretion is restricted by the liquid-impermeable sheet member, and on the other side in the thickness direction of the electrically conductive portion, contact between the electrically conductive portion and the excretion is easily formed. That is, influence of contact between the electrically conductive portion and the excretion can be restricted to one side in the thickness direction. For example, this makes it possible to select whether to detect influence of the skin-side (front sheet side) of the skin-side electrode or to detect influence of the non-skin-side (absorbent body side) of the skin-side electrode.

[0038] In the absorbent article, it is desirable that the skin-side electrodes and the non-skin-side electrodes each include the liquid-impermeable sheet member on the same side in the thickness direction.

[0039] According to the absorbent article described above, the conductive portion of each electrode is exposed on the same side in the thickness direction. Therefore, when connecting a detection device or the like to each electrode, the connection unit can be connected to the same side in the thickness direction, making it easier to work for mounting the detection device or the like.

[0040] In such an absorbent article, it is desirable that the skin-side electrode and the non-skin-side electrode each include the liquid-impermeable sheet member on the non-skin-side in the thickness direction.

[0041] According to the absorbent article described above, the conductive portion of each electrode is exposed on the skin-side in the thickness direction. Therefore, this makes it easier for excretions excreted on the skin-side of the absorbent article to come into contact with the conductive portion of each electrode, making it possible to more easily and accurately detect excretions.

[0042] In such an absorbent article, it is desirable that the width of the liquid-impermeable sheet member be greater than the width of the skin-side electrode and the non-skin-side electrode.

[0043] According to the absorbent article described above, on the side in the thickness direction on which the liquid-impermeable sheet member (base sheet) is provided, it is possible to more easily inhibit contact between the conductive portion and excretions. That is, it is possible to more easily prevent excretions from invading from both sides in the width direction of the liquid-impermeable sheet member and reaching the conductive portion. Therefore, the influence of the conductive portion and excretions can be easily limited to one side in the thickness direction (the side on which the liquid-impermeable sheet member is not provided).

[0044] In such an absorbent article, it is desirable that a liquid-impermeable region be provided on the side in the thickness direction opposite the side on which the liquid-impermeable sheet member is provided in at least a portion of each of the skin-side electrode and the non-skin-side electrode.

[0045] According to the absorbent article described above, for each electrode, it is possible to limit the conductive region. Therefore, compared to a case in which conduction is established between electrodes over the entire region, it is possible to keep the amount of change in the capacitance value and the resistance value detected between electrodes low. Therefore, even when the amount of urine or the like absorbed by the absorbent body increases, it is less likely that the resistance value will exceed the lower limit and the capacitance value will exceed the upper limit, making it possible to accurately measure.

[0046] In such an absorbent article, it is desirable that, in the longitudinal direction, the area of the liquid-impermeable region on the front side relative to the center be greater than the area of the liquid-impermeable region on the back side relative to the center.

[0047] According to the above-described absorbent article, the front region in the longitudinal direction is a region in which a large amount of urine is discharged, and it is easier to make the electrodes conductive between each other, so increasing the area of the liquid-impermeable region makes it possible to keep the amount of change in the capacitance and resistance values detected between the electrodes low. Therefore, even when the amount of urine absorbed by the absorbent increases, it is less likely that the resistance value will exceed the lower limit and that the capacitance value will exceed the upper limit, so it is possible to accurately measure.

[0048] In this absorbent article, it is desirable that the thickness of the liquid-permeable sheet be thicker than the thickness of the skin-side electrode and the non-skin-side electrode.

[0049] According to the above-described absorbent article, the thickness of the liquid-impermeable sheet (front sheet) is made as thick as possible, so it is easier to suppress phenomena such as direct contact between the wearer's body (skin) and the skin-side electrode when the absorbent article is put on. Therefore, it is possible to reduce the probability of false detection of the resistance value and the capacitance value.

[0050] In this absorbent article, it is desirable that the end portions of the skin-side electrode and the non-skin-side electrode in the longitudinal direction of the skin-side electrode and the non-skin-side electrode be positioned outside at least one of the ventral end and the dorsal end of the absorbent in the longitudinal direction.

[0051] According to the above-described absorbent article, the skin-side electrode and the non-skin-side electrode are each configured to extend to the longitudinal end region of the absorbent article. Therefore, when connecting a detection device or the like to each electrode, it is possible to perform work for connecting the device and each electrode in the longitudinal end region. Therefore, for example, it is possible to easily mount or detach the detection device even in a state in which the wearer has put on the absorbent article.

[0052] Further, a method of determining defecation / urination in an absorbent article including a liquid-absorbent absorbent, a liquid-permeable sheet configured on a skin side in a thickness direction with respect to the absorbent, and a liquid-impermeable sheet configured on a non-skin side in the thickness direction with respect to the absorbent, the method includes a skin-side capacitance detection process of detecting a size of a capacitance by a skin-side electrode provided between the liquid-permeable sheet and the absorbent, a non-skin-side capacitance detection process of detecting a size of a capacitance by a non-skin-side electrode provided between the liquid-impermeable sheet and the absorbent, and a determination process of determining whether excrement discharged on the absorbent article is feces or urine based on an amount of change in the capacitance detected in a predetermined period of time by the skin-side capacitance detection process and an amount of change in the capacitance detected in the predetermined period of time by the non-skin-side capacitance detection process.

[0053] According to the above-described defecation / urination determination method, changes in the skin-side capacitance value detected by the skin-side electrode and the non-skin-side capacitance value detected by the non-skin-side electrode over a predetermined period of time can be detected. Since the changes in the skin-side capacitance value and the non-skin-side capacitance value are expressed differently between during urination and during defecation, measurement of the expression of these changes makes it possible to accurately determine whether the excretion is feces or urine.

[0054] In this defecation / urination determination method, it is desirable that, if the amount of change in the capacitance detected by the skin-side electrode over the predetermined period of time is equal to or greater than a predetermined value, and if the amount of change in the capacitance detected by the non-skin-side electrode over the predetermined period of time is equal to or greater than the predetermined value, it is determined that urine has been excreted, and that, if the amount of change in the capacitance detected by the skin-side electrode over the predetermined period of time is equal to or greater than the predetermined value, and if the amount of change in the capacitance detected by the non-skin-side electrode over the predetermined period of time is less than the predetermined value, it is determined that feces has been excreted.

[0055] According to the above-described defecation / urination determination method, since urine penetrates into the absorbent, when urination is performed, both the skin-side electrode and the non-skin-side electrode are turned on, and the capacitance is more likely to change significantly. On the other hand, since the amount of feces that penetrates into the absorbent is small, when defecation is performed, the skin-side electrode is turned on, and the capacitance changes significantly. However, the non-skin-side electrode is less likely to be turned on, and the capacitance is less likely to change. Therefore, by utilizing this property, it is possible to more accurately determine whether the excretion is feces or urine.

[0056] In this defecation / urination determination method, it is desirable that, with respect to the time at which the capacitance detected by the skin-side electrode changes over the predetermined period of time, and with respect to the time at which the capacitance detected by the non-skin-side electrode changes over the predetermined period of time, the difference between these times is used as an additional index for determining urination.

[0057] According to the above-described defecation / urination determination method, in a case where urination has been performed, a predetermined time difference is generated between the time at which urine reaches the skin-side electrode located on the skin-side of the absorbent and the time at which the urine penetrates into the absorbent and reaches the non-skin-side electrode located on the non-skin-side of the absorbent. Therefore, by taking into account the difference in the time at which the capacitance detected by each electrode changes, it is possible to more accurately determine urination.

[0058] In this defecation / urination determination method, it is desirable that, regarding the time at which the change in the capacitance detected by the skin-side electrode within the predetermined period of time and the time at which the change in the capacitance detected by the non-skin-side electrode within the predetermined period of time, in the case where these times are the same, this case is determined to be noise.

[0059] According to the above defecation / urination determination method, when urination is performed, the non-skin-side capacitance is considered to normally start to change after a predetermined time elapses from when the skin-side capacitance starts to change. Therefore, if the time at which the skin-side capacitance starts to change and the time at which the non-skin-side capacitance starts to change are the same, this is different from the manifestation of normal urination. Therefore, this case is treated as noise, and it is possible to suppress false determination.

[0060] In this defecation / urination determination method, it is desirable that the method further includes skin-side resistance detection processing that detects the magnitude of a resistance value by the skin-side electrode, and regarding the degree of recovery after the change in the resistance value detected by the skin-side electrode within the predetermined period of time, the degree is used as an additional index for determining urination.

[0061] According to the above defecation / urination determination method, when urination has been performed, the resistance value detected by the skin-side electrode tends to manifest as follows: the resistance value decreases immediately after urination due to conduction between the skin-side electrodes, and the resistance value increases when a predetermined time elapses due to the fact that the skin-side electrodes are not in conduction because the urine is absorbed by the absorbent. Therefore, by taking into account the degree of temporal change (degree of recovery) in the resistance value detected by the skin-side electrode, it is possible to more accurately determine urination.

[0062] In this defecation / urination determination method, it is desirable that, regarding the degree of recovery after the change in the capacitance value detected by the skin-side electrode within the predetermined period of time, the degree is used as an additional index for determining defecation.

[0063] According to the above defecation / urination determination method, if defecation has been performed, the feces adhering to the skin-side surface of the absorbent continuously remains without being absorbed, and thus the capacitance detected by the skin-side electrode is unlikely to change even after a predetermined time elapses. Therefore, by taking into account the degree of temporal change (degree of recovery) in the capacitance detected by the skin-side electrode, it is possible to more accurately determine defecation.

[0064] First Embodiment

[0065] As an example of the absorbent article according to the first embodiment, an absorbent pad 1 that absorbs excretions such as urine or feces will be described. The absorbent pad 1 is attached to the inner side of a general disposable diaper (for example, the disposable diaper 101 described below).

[0066] Basic configuration

[0067] Disposable diaper 101

[0068] First, a disposable diaper 101 (hereinafter, also simply referred to as "diaper 101") in which the absorbent pad 1 is installed will be described. Figure 1 A is a schematic plan view showing an unfolded state of the diaper 101. Figure 1 B is a schematic cross-sectional view showing a cross section taken along Figure 1 A. It should be noted that, although Figure 1 The diaper 101 shown in A is a so-called belt-type disposable diaper, but the absorbent pad 1 can be used in a disposable diaper of another type (for example, a pant-type disposable diaper) other than the belt-type disposable diaper.

[0069] In Figure 1 A and Figure 1 B, the diaper 101 has a longitudinal direction, a width direction, and a thickness direction that intersect each other. The front side portion in the longitudinal direction is a portion positioned on the ventral side of the wearer when the diaper 101 is put on, and the back side portion in the longitudinal direction is a portion positioned on the dorsal side of the wearer. Further, the skin side in the thickness direction is a side that comes into contact with the body (skin) of the wearer when the diaper 101 is put on, and the non-skin side in the thickness direction is a side that does not come into contact with the body (skin) of the wearer.

[0070] The diaper 101 includes an absorbent core 111 formed of a liquid-absorbing material such as pulp fiber, a liquid-permeable surface sheet 121 that covers the absorbent core 111 from the skin side in the thickness direction, a liquid-impermeable back sheet 131 that covers the absorbent core 111 from the non-skin side, and a pair of fastening belts 141 provided in the width direction both end portions of the back side (dorsal side) in the longitudinal direction. Further, as shown in Figure 1 A, the shape of the diaper 101 in the unfolded state is a substantially hourglass shape having the longitudinal direction and the width direction. That is, the diaper 101 has a shape in which the longitudinal direction central portion narrows in the width direction inner side. This narrow portion serves as a crotch portion, and is applied to the crotch of the wearer. The ventral side portion in the longitudinal direction with respect to the crotch portion serves as a front panel, and is applied to the lower abdominal portion of the wearer. The dorsal side portion in the longitudinal direction with respect to the crotch portion serves as a back panel, and is applied to the buttocks of the wearer. The front panel and the back panel are fastened by the fastening belts 141. In this way, the diaper 101 is put on the lower half of the wearer.

[0071] The absorbent pad 1 according to the present embodiment is placed and attached to the skin-side surface of the surface sheet 121 of the diaper 101. Thus, when the wearer puts on the diaper 101 in this state, the absorbent pad 1 is worn on the lower body of the wearer while being integrated with the diaper 101. Note that in some cases, an anti-shift adhesive portion formed of a hot-melt adhesive or a male member of a hook-and-loop fastener, or the like can be provided on the non-skin-side surface of the absorbent pad 1 to fix the absorbent pad 1 so as not to relatively move from the state in which the absorbent pad 1 is placed on the diaper 101.

[0072] Absorbent pad 1

[0073] Next, the absorbent pad 1 will be described. Figure 2 is a schematic plan view of the absorbent pad 1. Figure 3 is a schematic cross-sectional view showing a cross section taken along the line A-A in Figure 2 As shown in Figure 2 and Figure 3 , the absorbent pad 1 has a longitudinal direction, a width direction, and a thickness direction as three directions orthogonal to each other. These directions correspond to the longitudinal direction, the width direction, and the thickness direction in Figure 1 , respectively.

[0074] The absorbent pad 1 is an absorbent article used for attachment to the skin-side surface of a diaper 101, and as shown in Figure 2 , has a substantially hourglass shape in which the longitudinal central portion narrows in the width direction inner side. The absorbent pad 1 includes an absorbent body 2, a front sheet 3 disposed on the skin side with respect to the absorbent body 2 in the thickness direction, a leakage-preventing sheet 4 disposed on the non-skin side with respect to the absorbent body 2 in the thickness direction, and a back sheet 5 disposed on the non-skin side of the leakage-preventing sheet 4. Further, the absorbent pad 1 is provided with an electrode 10 for detecting urination and defecation. Components adjacent to each other in the thickness direction are joined to each other by a joining material such as a hot-melt adhesive or the like.

[0075] The absorbent body 2 is a liquid-absorbing member having an absorbent core 21 and a core wrap sheet 22. The absorbent core 21 includes a polymer absorbent (absorbing polymer: superabsorbing polymer, hereinafter also referred to as "SAP") and a liquid-absorbing fiber such as pulp fiber or the like, and like the absorbent pad 1, has a substantially hourglass shape in which the longitudinal central portion narrows in the width direction inner side (see Figure 2 ). In the present embodiment, as shown in Figure 3 , the absorbent core 21 has a double-layer structure including a skin-side core layer 21A disposed on the skin side in the thickness direction and a non-skin-side core layer 21B superposed on the non-skin side of the skin-side core layer 21A. However, the absorbent core 21 can have a single-layer structure or a multi-layer structure having three or more core layers. The core wrap sheet 22 is a liquid-permeable sheet member that covers the absorbent core 21, and is formed of, for example, a thin tissue paper or the like.

[0076] Note that the configuration of the absorbent body 2 is not limited to the above, and examples thereof include an SAP sheet in which an SAP layer is attached to a hydrophilic sheet, an air-laid sheet in which liquid-absorbent fibers are formed into a sheet by an air-laid method, and the like.

[0077] The front sheet 3 is a liquid-permeable sheet member (liquid-permeable sheet) disposed on the skin side in the thickness direction of the absorbent pad 1, and is a member that comes into direct contact with the wearer's skin when the absorbent pad 1 is put on. The front sheet 3 receives urine and feces excreted from the human body, and quickly absorbs the urine and feces in the thickness direction to introduce the urine and feces to the absorbent body 2 (absorbent core 21). As for the front sheet 3, a sheet larger than the planar shape of the absorbent body 2 is used. As a sheet member constituting the front sheet 3 of the present embodiment, a thermobonded nonwoven fabric, a spunbonded nonwoven fabric, or the like can be exemplified.

[0078] The leakage-preventing sheet 4 is a liquid-impermeable sheet member (liquid-impermeable sheet) disposed on the non-skin side in the thickness direction of the absorbent pad 1 with respect to the absorbent body 2. As for the leakage-preventing sheet 4, a sheet larger than the planar shape of the absorbent body 2 is used, and the leakage-preventing sheet 4 is provided to prevent liquid such as urine, which has been absorbed by the absorbent body 2, from permeating into the clothing side (non-skin side) of the wearer. As a sheet member constituting the leakage-preventing sheet 4 of the present embodiment, a resin film made of polyethylene or polypropylene, or the like can be exemplified.

[0079] The back sheet 5 is a member (outer wrapping sheet) disposed on the non-skin side of the leakage-preventing sheet 4 in the thickness direction of the absorbent pad 1, and constitutes the outer wrapping of the absorbent pad 1. The back sheet 5 has substantially the same size as the leakage-preventing sheet 4. Examples of a sheet member constituting the back sheet 5 of the present embodiment include a thermobonded nonwoven fabric, and the like. Furthermore, on the non-skin side surface of the back sheet 5, a shift-preventing adhesive portion or the like for attaching and fixing the skin side surface of the absorbent pad 1 to the diaper 101 can be provided.

[0080] Furthermore, although Figure 2 and Figure 3 not shown in FIGS. 1 and 2, a pair of leakage-preventing wall portions that suppress lateral leakage of urine and the like can be provided in the skin side in the thickness direction of the absorbent body 2 and both end portions in the width direction of the absorbent body 2. Since the leakage-preventing wall portions are well known, a detailed description thereof will be omitted.

[0081] The electrode 10

[0082] Electrode 10 is a detection part used to detect excretion by contacting excrement (e.g., urine or feces) excreted from the wearer. In the thickness direction, electrode 10 of this embodiment includes: a skin-side electrode 11 disposed between the front sheet (liquid-permeable sheet) 3 and the absorbent body 2; and a non-skin-side electrode 12 disposed between the leak-proof sheet (liquid-impermeable sheet) 4 and the absorbent body 2 (see [link to relevant documentation]). Figure 3 The skin-side electrode 11 is a strip electrode that extends longitudinally and is arranged in pairs at predetermined intervals in the width direction (see...). Figure 2 Similarly, the non-skin-side electrode 12 is a strip-shaped electrode that extends longitudinally and is arranged in pairs in the width direction at predetermined intervals (different from the intervals between the skin-side electrodes 11). However, multiple pairs of electrodes 11 and 12 can be provided.

[0083] Figure 4 These are schematic plan and cross-sectional views illustrating an example of the construction of a pair of skin-side electrodes 11 and 11. Skin-side electrode 11 includes a conductive portion 111, a substrate 112, and a cover portion 113. The conductive portion 111 is formed by continuously applying a strip of conductive ink along the entire longitudinal length of the absorbent pad 1. In this embodiment, as along... Figure 4 The cross-sectional view taken by CC in the figure shows that the substrate 112 is subjected to cross-sectional views on one side surface in the thickness direction. Figure 4 Conductive ink is applied to the skin-side surface to form a conductive portion 111. The conductive ink is prepared by kneading together a binder, conductive metal powder, and filler. As such a binder, polyvinyl chloride-based resins, polyacrylic acid-based resins, epoxy resins, polyester resins, polyacrylamide-based resins, polyolefin resins, polyurethane resins, phenolic resins, etc., can be used. As such a conductive metal powder, silver, gold, copper, nickel, aluminum, or conductive carbon, etc., can be used. Such fillers include viscosity modifiers, dispersants, etc. It should be noted that the structure of the conductive ink is not limited to these examples, but from the perspective of detection accuracy, it is desirable for the conductive ink to be formed of a material that facilitates current flow and has the lowest possible resistance.

[0084] The substrate 112 is a flexible, liquid-impermeable sheet component and is formed of a material with a lower conductivity than the conductive portion 111. As the material for the substrate 112, biaxially stretched films made of, for example, polypropylene, polyethylene, polyvinyl chloride, polyester, polyamide, polyimide, polyamide-imide, polycarbonate, or polystyrene can be used. In this embodiment, flexibility is imparted to the substrate 112 (the liquid-impermeable sheet component) by annealing (heat treatment) a PET sheet with a thickness of approximately 25 μm. This makes it less likely that the wearer will experience discomfort when wearing the absorbent pad 1.

[0085] The substrate 112 is arranged on one side in the thickness direction of the conductive portion 111, and thus the influence of contact between the conductive portion 111 and excrement can be limited to one side in the thickness direction. That is, on one side in the thickness direction, the conductive portion 111 is limited from contact with excrement by the substrate 112, and on the other side in the thickness direction, the conductive portion 111 is exposed and thus easily comes into contact with excrement. Therefore, if the conductive portion 111 is arranged on the skin side (see Figure 4 ) of the substrate 112 (liquid-impermeable sheet member), it is easier to detect the influence of excrement that has adhered to the side of the front sheet 3 (liquid-permeable sheet) in the skin side electrode 11. On the other hand, if the conductive portion 111 is arranged on the non-skin side (not shown) of the substrate 112, it is easier to detect the influence of excrement that has adhered to the skin side surface of the absorbent body 2 in the skin side electrode 11. In this way, by limiting the surface of the conductive portion 111 exposed in the skin side electrode 11 to only one side in the thickness direction, it is possible to select whether to detect the influence of the side of the front sheet 3 (liquid-permeable sheet) or the influence of the side of the absorbent body 2.

[0086] Further, the width direction both end portions of the substrate 112 are positioned outside the width direction both end portions of the conductive portion 111. That is, the width of the substrate 112 is greater than the width of the conductive portion 111, and the conductive portion 111 is not arranged in the width direction both end portions of the substrate 112. With this configuration, it is easier to suppress contact between the conductive portion 111 on the side where the substrate 112 is arranged in the thickness direction and excrement. For example, it is possible to prevent excrement from invading from the width direction both sides of the substrate 112 and reaching the conductive portion 111. That is, the influence of contact between the conductive portion 111 and excrement can be limited to only one side in the thickness direction (the side where the substrate 112 is not arranged).

[0087] As shown in the cross section taken along D-D in Figure 4 As shown in the cross section taken along D-D in Figure 4The cover 113 is a liquid-impermeable member that covers at least a portion of the conductive portion 111 on the skin side. For example, the cover 113 can be formed of a film of polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PE), etc. The cover 113 forms a liquid-impermeable region in at least a portion on the side opposite to the side where the substrate 112 (liquid-impermeable sheet member) is disposed in the thickness direction of the skin-side electrode 11. In the liquid-impermeable region, contact between moisture such as urine and the conductive portion 111 is suppressed. Therefore, in the skin-side electrode 11, the current between a pair of skin-side electrodes 11 and 11 is unlikely to flow in the liquid-impermeable region where the conductive portion 111 is covered by the cover 113 on the skin side. On the other hand, in the skin-side electrode 11, in the area where the conductive part 111 is exposed but not covered by the covering part 113 (hereinafter also referred to as the "permeable area"), moisture such as urine between the pair of skin-side electrodes 11 and 11 makes the electrodes 11 conductive, making it easier for current to flow.

[0088] In the skin-side electrode 11 of this embodiment, as Figure 4 As shown, the conductive area is limited because permeable and impermeable regions alternate longitudinally. If impermeable regions are not provided in the skin-side electrode 11, the entire area between the pair of skin-side electrodes 11 and 11 can be made conductive, allowing current to flow easily. That is, this makes it easier to reduce the resistance value detected between the electrodes and easier to increase the capacitance value detected between the electrodes. In this case, as the amount of urine or the like absorbed by the absorbent 2 increases, the detectable resistance becomes more likely to exceed the lower limit value, and the capacitance becomes more likely to exceed the upper limit value, leading to the risk of inaccurate measurement. Conversely, in this embodiment, since the impermeable regions are provided to partially restrict the flow of current between the pair of skin-side electrodes 11 and 11, the resistance becomes less likely to exceed the lower limit value and the capacitance becomes less likely to exceed the upper limit value. This allows for accurate measurement even when the amount of absorbed urine or the like increases.

[0089] Further, it is desirable that the sum of the lengths L113 in the region on the front side with respect to the longitudinal center be greater than the sum of the lengths L113 in the region on the back side with respect to the longitudinal center in the longitudinal direction. In other words, it is desirable that the area of the liquid- impermeable region on the front side with respect to the longitudinal center be greater than the area of the liquid-impermeable region on the back side with respect to the longitudinal center. The region on the front side in the longitudinal direction is more likely to discharge a large amount of urine, making it easier to make the electrodes 11 and 11 conductive. Therefore, by increasing the area of the liquid-impermeable region in this region, even when the amount of urine absorbed increases, it is possible to make the resistance value less likely to exceed the lower limit and make the capacitance value less likely to exceed the upper limit. This can make it easier to achieve more accurate measurement.

[0090] Further, the interval in the width direction between the pair of skin-side electrodes 11 and 11 is defined as W11. W11 refers to the distance in the width direction between the inner ends of the pair of conductive portions 111 and 111 (see Figure 4 In the present embodiment, the skin-side electrodes 11 are configured so that the interval W11 is 40 mm or greater. If the interval W11 is less than 40 mm, the current is likely to flow excessively between the electrodes and cause noise and the like, and false detection is likely to occur. Further, in the case where the interval W11 between the electrodes is 40 mm or greater, it is easier to appropriately adjust the upper limit and lower limit of the capacitance value and resistance value detected between the electrodes.

[0091] The configuration of the pair of non-skin-side electrodes 12 and 12 is also substantially the same as that of the pair of skin-side electrodes 11 and 11 shown in Figure 4 . That is, the non-skin-side electrodes 12 include the conductive portions 121, the substrate 122 (liquid-impermeable sheet member), and the cover portions 123. Further, for the same reasons as the skin-side electrodes 11, it is desirable that the interval W12 in the width direction between the pair of non-skin-side electrodes 12 and 12 be 40 mm or greater. However, in the present embodiment, the width direction interval W12 between the pair of non-skin-side electrodes 12 and 12 is different from the width direction interval W11 between the pair of skin-side electrodes 11 and 11. More specifically, the interval W12 is smaller than the interval W11 (W11 > W12, see Figure 2 In the case of urination, the skin-side surface of the absorber 21 is more likely to become wet, and thus the interval W11 between the skin-side electrodes 11 and 11 to which urine is likely to reach is expanded, making it possible to relatively suppress the increase in the capacitance value and the decrease in the resistance value with respect to the non-skin-side electrodes 12 and 12. Therefore, this makes it possible to suppress the judgment that cannot use the combination of the changes in the detection values based on both the electrodes 11 and 12 (details will be described later).

[0092] Further, in the present embodiment, it is desirable that the thickness of the front sheet 3 (liquid-permeable sheet) be thicker than the thickness of each of the electrodes 11 and 12. Specifically, it is desirable that the thickness of the base sheets 111 and 112 that respectively constitute the electrodes 11 and 12 be approximately 25 μm, and that the thickness of the front sheet 3 be approximately 0.5 mm to 1.5 mm. When the absorbent pad 1 is put on, the front sheet 3 is positioned between the wearer's body (skin) and the skin-side electrode 11. Therefore, making the thickness of the front sheet 3 as thick as possible makes it easier to suppress the influence of the wearer's body coming into contact with the skin-side electrode 11, makes it easier to suppress the influence of the wearer's body pressing against the skin-side electrode 11, and so on. Thus, it is possible to reduce the probability of erroneous detection of the resistance value and the capacitance in the electrodes 11 and 12.

[0093] Method for detecting excrement

[0094] A method for detecting excrement using the absorbent pad 1 will be described. Figure 5 is a conceptual diagram of an excrement detection circuit using the absorbent pad 1. In the case of detecting excrement, the absorbent pad 1 is connected to the detection device 50 and the information processing apparatus 60, and various data are measured.

[0095] The detection device 50 is a device that applies an AC current to the electrodes 10 (the skin-side electrodes 11 and the non-skin-side electrodes 12) of the absorbent pad 1 and measures the capacitance value and the resistance value each detected between a pair of the skin-side electrodes 11 and 11 and a pair of the non-skin-side electrodes 12 and 12. The detection device 50 includes a main unit 51, a connection unit 52, and a data transmission and reception unit 53.

[0096] The main unit 51 includes at least a power supply unit (a battery, a battery unit, or the like) for applying a current to the electrodes 10, and a measurement unit (neither is shown) for measuring the capacitance value and the resistance value detected by the electrodes 10. Further, the main unit 51 can include a ground wire or the like in order to release the electric energy charged in the electrodes 10. It should be noted that, in the case of applying a DC current to the electrodes 10, it is desirable that a polarity inversion circuit for applying a current having different polarities to the left and right pairs of the electrodes 11 and 11 (12 and 12) be provided.

[0097] The connection unit 52 is a connector that connects the main unit 51 and the electrodes 11 and 12 of the absorbent pad 1. The current is applied to the electrodes 10 and the capacitance value and the resistance value between the electrodes are detected by the connection unit 52. In the present embodiment, the interval W11 in the width direction between the pair of the skin-side electrodes 11 and 11 is different from the interval W12 in the width direction between the pair of the non-skin-side electrodes 12 and 12, and thus each of the electrodes 11 and 12 is arranged at a different position in the width direction. That is, since the positions of the electrodes do not overlap with respect to the width direction, as shown in Figure 5As shown, the connection units 52 are easily connected to each of the electrodes 11 and 12, and the detection device 50 can be easily mounted.

[0098] Further, as Figure 3 and Figure 4 shown, in the present embodiment, in both the skin-side electrode 11 and the non-skin-side electrode 12, the substrates 112 and 122 are disposed on the same side in the thickness direction. In other words, the conductive portions 111 and 121 are in a state of being exposed on the same side in the thickness direction. This enables each of the connection units 52 to be connected to each of the electrodes 11 and 12 on the same side in the thickness direction, making it easier to mount the detection device 50.

[0099] Further, it is desirable that, in the longitudinal direction, the end portions of the skin-side electrode 11 and the non-skin-side electrode 12 are positioned outside at least one of the ventral end portion and the dorsal end portion of the absorbent body 2. In the present embodiment, as Figure 2 and Figure 5 shown, in the longitudinal direction, the ventral end portions of the skin-side electrode 11 and the non-skin-side electrode 12 are positioned outside the ventral end portion of the absorbent body 2. That is, both the skin-side electrode 11 and the non-skin-side electrode 12 are configured to extend to the ventral end region of the absorbent pad 1 in the longitudinal direction. Therefore, in the ventral end region in the longitudinal direction, work for connecting each of the electrodes 11 and 12 to the connection units 52 can be performed. Since the connection position is in the ventral end portion in the longitudinal direction, the detection device 50 can be easily mounted or detached even in a state in which the wearer puts on the absorbent pad 1.

[0100] The information processing apparatus 60 is configured from, for example, a workstation, a personal computer, or the like, and has a function as a so-called server. In the present embodiment, the information processing apparatus 60 stores various data transmitted by the detection device 50, and based on the data, detects that excretion has been performed, and performs processing of determining whether the excrement is feces or urine and determining the amount of excretion (for example, the amount of excreted urine). The various processes performed by the information processing apparatus 60 will be described later.

[0101] It should be noted that by communicably connecting the information processing apparatus 60 to a plurality of different absorbent pads 1 (and detection devices 50), it is possible to detect the excretion state of a plurality of users (wearers of the absorbent pads 1). Further, by connection with an external terminal such as a smartphone or the like, it is possible to transmit information on the excretion state to the terminal and receive information on the excretion state from the terminal. Further, a configuration in which the detection device 50 has the function of the information processing apparatus 60 and performs processing of detecting excretion or various determinations by itself is also acceptable.

[0102] Further, a configuration in which the information processing apparatus 60 acquires the detection results of urination and defecation respectively and performs various estimations based on the detection results acquired respectively is also acceptable. In the present embodiment, on the skin surface side of the absorbent body 2, the skin side electrode 11 detects the capacitance value and the resistance value based on the excreta adhering to the front sheet 3, and these electrical characteristic values are mainly used to estimate whether or not defecation is present. On the other hand, on the non-skin surface side of the absorbent body 2, the non-skin side electrode 12 detects the capacitance value and the resistance value based on the excreta absorbed in the absorbent core 21, and these electrical characteristic values are mainly used to estimate whether or not urination is present. That is, the electrical characteristic values mainly used for defecation determination and the electrical characteristic values mainly used for urination determination are detected respectively and are transmitted to the information processing apparatus 60 respectively. In this case, it can be said that the information processing apparatus 60 acquires defecation information and urination information respectively, the defecation information being information about defecation of the user, and the urination information being information about urination of the user.

[0103] That is, the structures (electrodes) for measuring capacitance and resistance are located at different positions of the absorbent article, and the electrical characteristic values (capacitance value and resistance value) detected by each structure (electrode) are associated with information indicating which structure detected the information, and the results are transmitted to the information processing apparatus 60 respectively. The information processing apparatus 60 having acquired the information can estimate defecation and urination.

[0104] If the information processing apparatus 60 acquires the information as described above respectively, appropriate processing can be performed more easily according to each case of urination and defecation. For example, if defecation information is acquired, an alarm is issued to prompt a caregiver or the like to immediately replace the absorbent pad 1. On the other hand, if urination information is acquired, an alarm is issued when the absorption capacity reaches a limit determined in accordance with the absorption capacity (the capacity capable of absorbing urine) of the absorbent core 21. This makes it easier for the caregiver to recognize an appropriate timing for replacing the absorbent pad 1, and this makes it possible to reduce the burden of the confirmation work for replacing the absorbent pad 1 and the burden of the cleaning process when excretion leakage occurs.

[0105] Further, a configuration in which the electrical characteristic values (capacitance value and resistance value) detected by each structure (electrode) are periodically transmitted to the information processing apparatus 60 and the information processing apparatus 60 performs various estimations based on changes in the electrical characteristic values is also acceptable. For example, the information processing apparatus 60 can improve the accuracy of estimation of defecation and urination by storing the information acquired periodically, generating an excretion history for each user, and using the excretion history. In addition, by monitoring changes in the electrical characteristic values, it is possible to estimate, for example, the amount of excretion and the quality of feces when the excreta are feces.

[0106] Next, the principle of detecting urine using the absorbent pad 1 will be described. Figure 6 A and Figure 6B is a diagram showing the principle of detecting urine when urinating. Figure 6 A is Figure 3 A schematic cross-sectional view of the absorbent pad 1 is shown, and a state after urine has just been discharged on the skin-side surface of the absorbent pad 1 is shown. Further, Figure 6 B shows a state after a predetermined time (for example, 30 seconds) has passed from Figure 6 A.

[0107] When urinating in a state where the wearer wears the absorbent pad 1, the discharged urine first adheres to the skin-side surface of the front sheet 3, then penetrates into the front sheet 3 from the skin side to the non-skin side in the thickness direction, and moves to the absorbent body 2. At this time, there is a case where the skin-side electrode 11 disposed between the front sheet 3 and the absorbent body 2 comes into contact with the urine depending on conditions such as the amount of the discharged urine. In Figure 6 A, the urine is discharged so as to cross a pair of skin-side electrodes 11 and 11 which are separated from each other in the width direction with an interval W11. Therefore, the moisture contained in the urine makes the conductive portions 111 and 111 conductive, and the current flows more easily between the skin-side electrodes 11 and 11 compared to the state before urination (i.e., a state where the skin-side electrodes 11 and 11 are insulated due to dryness).

[0108] Therefore, the resistance value R11 detected between the pair of skin-side electrodes 11 and 11 is large (the current is less likely to flow) before the moisture in the urine makes the skin-side electrodes 11 and 11 conductive, and the resistance value R11 decreases (the current flows more easily) when the moisture in the urine makes the skin-side electrodes 11 and 11 conductive. On the other hand, the capacitance value C11 detected between the pair of skin-side electrodes 11 and 11 is small (the electric charge is less likely to accumulate) before the moisture in the urine makes the skin-side electrodes 11 and 11 conductive, and the capacitance value C11 increases (the electric charge is more likely to accumulate) when the moisture in the urine makes the skin-side electrodes 11 and 11 conductive.

[0109] When a predetermined time has passed after the urine is discharged, the urine which has penetrated into the front sheet 3 is absorbed by the absorbent body 2, and penetrates into the inside of the absorbent body 2 from the skin side to the non-skin side. At this time, there is a case where the non-skin-side electrode 12 disposed between the absorbent body 2 and the leakage prevention sheet 4 comes into contact with the urine. In Figure 6 B, the urine (indicated by a hatched portion in Figure 6 B) absorbed by the absorbent body 2 diffuses so as to cross a pair of non-skin-side electrodes 12 and 12 which are separated from each other in the width direction with an interval W12. Therefore, the moisture contained in the urine makes the conductive portions 121 and 121 of the non-skin-side electrodes 12 conductive, and the current flows more easily between the non-skin-side electrodes 12 and 12 compared to the state before urination (i.e., a state where the non-skin-side electrodes 12 and 12 are insulated due to dryness).

[0110] The resistance value R12 and the capacitance value C12 detected by the non-skin side electrodes 12 exhibit substantially the same as the skin side electrodes 11. That is, the resistance value R12 detected between the pair of non-skin side electrodes 12 and 12 is large (current is less likely to flow) before the moisture in the urine makes the non-skin side electrodes 12 and 12 conductive, and the resistance value R12 decreases (current is more likely to flow) when the moisture in the urine makes the non-skin side electrodes 12 and 12 conductive. On the other hand, the capacitance value C12 detected between the non-skin side electrodes 12 and 12 is small (charge is less likely to accumulate) before the moisture in the urine makes the non-skin side electrodes 12 and 12 conductive, and the capacitance value C12 increases (charge is likely to accumulate) when the moisture in the urine makes the non-skin side electrodes 12 and 12 conductive.

[0111] It should be noted that in the present embodiment, the skin side electrodes 11 and the non-skin side electrodes 12 are each provided with a liquid-impermeable base sheet 112 and 122 on the non-skin side in the thickness direction. The conductive portions 111 and 121 are each in a state of being exposed to the skin side. Thus, this makes it easier for excreta such as urine and the like excreted on the skin side to come into contact with the conductive portions 111 and 121 of the electrodes 11 and 12, making it possible to more easily detect the excreta.

[0112] Next, the principle of detecting feces using the absorbent pad 1 will be described. Figure 7 A and Figure 7 B is a diagram showing the principle of detecting feces when the feces are excreted. Figure 7 A is Figure 3 a schematic cross-sectional view of the absorbent pad 1, and shows a state after the feces have just been excreted on the skin side surface of the absorbent pad 1. Further, Figure 7 B shows a state after a predetermined time (for example, 30 seconds) has elapsed from Figure 7 A.

[0113] When defecation is performed in a state where the wearer is wearing the absorbent pad 1, the excreted feces adhere to the skin side surface of the front sheet 3. At this time, there is a case where the moisture contained in the feces penetrates into the front sheet 3 and comes into contact with the skin side electrodes 11 disposed between the front sheet 3 and the absorbent body 2. In Figure 7 A, the feces are excreted so as to cross the pair of skin side electrodes 11 and 11 in the width direction. Thus, the moisture contained in the feces makes the conductive portions 111 and 111 conductive, and current is more likely to flow between the skin side electrodes 11 and 11 compared to the state before defecation (i.e., a state where the skin side electrodes 11 and 11 are insulated due to dryness).

[0114] Therefore, the resistance value R11 detected between the pair of skin-side electrodes 11 and 11 is large (current is less likely to flow) before the moisture in the feces makes the skin-side electrodes 11 and 11 conductive, and the resistance value R11 decreases (current is more likely to flow) when the moisture in the feces makes the skin-side electrodes 11 and 11 conductive. On the other hand, the capacitance value C11 detected between the pair of skin-side electrodes 11 and 11 is small (charge is less likely to accumulate) before the moisture in the feces makes the skin-side electrodes 11 and 11 conductive, and the capacitance value C11 increases (charge is more likely to accumulate) when the moisture in the feces makes the skin-side electrodes 11 and 11 conductive.

[0115] On the other hand, the amount of moisture contained in the feces is smaller than the amount of moisture contained in the urine, and the feces are less likely to penetrate into the absorbent body 2, and therefore even after a predetermined time elapses from the excretion of the feces, the moisture contained in the feces is less likely to reach the non-skin side of the absorbent body 2. That is, the moisture in the feces is less likely to come into contact with the non-skin-side electrodes 12 disposed between the absorbent body 2 and the leakage prevention sheet 4. In Figure 7 In B, the moisture contained in the feces remains on the skin-side surface portion of the absorbent body 2 (in the Figure 7 In B, the moisture contained in the feces remains on the skin-side surface portion of the absorbent body 2 (in the

[0116] That is, the non-skin-side electrodes 12 are less likely to be affected by the moisture in the feces, and the state between the electrodes is less likely to change before and after defecation. Therefore, the resistance value R12 detected between the pair of non-skin-side electrodes 12 and 12 is less likely to change before and after defecation. Similarly, the capacitance value C12 detected between the pair of non-skin-side electrodes 12 and 12 is less likely to change before and after defecation.

[0117] As described above, when defecation is performed, the resistance value R11 and the capacitance value C11 detected by the skin-side electrodes 11 change, but the resistance value R12 and the capacitance value C12 detected by the non-skin-side electrodes 12 do not substantially change. Therefore, by monitoring the time changes in the resistance values and the capacitance values detected by the skin-side electrodes 11 and the non-skin-side electrodes 12, it is possible to accurately determine whether the excretion is feces or urine.

[0118] Figure 8 is a flowchart showing an example of a defecation / urination determination process using the absorbent pad 1. Various processes in the defecation / urination determination are mainly executed by the information processing apparatus 60. Hereinafter, for the sake of simplicity of explanation, the explanation will be made on the assumption that various processes are executed by the detection device 50.

[0119] When the excretion detection is started, the detection device 50 intermittently applies electric current to each of the electrodes 11 and 12 of the absorbent pad 1. Then, the following detection processes are executed (S101): a non-skin side capacitance detection process that detects the magnitude of the capacitance value C12 between the non-skin side electrodes 12 and 12; and a skin side capacitance detection process that detects the magnitude of the capacitance value C11 between the skin side electrodes 11 and 11.

[0120] Next, the detection device 50 (the information processing apparatus 60) determines the amount of change in the capacitance value C12 over a predetermined period of time (for example, a measurement period of about 1 to 30 seconds) based on the detection result of the non-skin side capacitance detection process (S102). As a result, if the amount of change in the capacitance value C12 is equal to or greater than a predetermined magnitude (Yes in S102), the process proceeds to step S103. The case where the amount of change in the capacitance value C12 is equal to or greater than the predetermined magnitude means a state in which moisture such as urine reaches between the pair of non-skin side electrodes 12 and 12 and makes the electrodes conductive between them as shown in Figure 6 B. That is, this indicates a high possibility that urination has been performed.

[0121] On the other hand, if the amount of change in the capacitance value C12 is less than the predetermined magnitude (No in S102), the process proceeds to step S104. The case where the amount of change in the capacitance value C12 is not greater than or less than the predetermined magnitude means a state in which moisture does not reach between the pair of non-skin side electrodes 12 and 12 and does not make the electrodes conductive between them as shown in Figure 7 B. That is, this indicates a high possibility that defecation or neither urination nor defecation has been performed.

[0122] In step S103, the detection device 50 determines the amount of change in the capacitance value C11 over a predetermined period of time based on the detection result of the skin side capacitance detection process (S103). As a result, if the amount of change in the capacitance value C11 is equal to or greater than a predetermined magnitude (Yes in S103), the process proceeds to step S105. The case where the amount of change in the capacitance value C11 is equal to or greater than the predetermined magnitude means a state in which moisture such as urine reaches between the pair of skin side electrodes 11 and 11 and makes the electrodes conductive between them as shown in Figure 6 A. That is, it means a state in which the pair of non-skin side electrodes 12 and 12 are conductive in S102 and the pair of skin side electrodes 11 and 11 are conductive in S103.

[0123] Therefore, the conduction of both the skin side electrodes 11 and the non-skin side electrodes 12 indicates that the amount of liquid (urine) sufficient to reach the interval between the skin side electrodes 11 and 11 and between the non-skin side electrodes 12 and 12 is absorbed by the absorbent body 2. Therefore, in this case, the detection device 50 determines that urination has been performed (S105).

[0124] If it is determined that urination has occurred in S105, the detection device 50 issues a reminder (an alarm) for notifying the user (wearer or caregiver) that urination has occurred (S109). For example, the detection device 50 alarms by emitting a sound of a buzzer or sends an alarm information to the information processing apparatus 60 so as to cause the display unit (e.g., a display) of the information processing apparatus 60 to display a screen informing that urination has occurred. Alternatively, the alarm information can be sent to another terminal by the information processing apparatus 60 and the alarm information is displayed on the display unit of the other terminal. For example, the reminder can be output to a facility terminal installed at the center of caregivers and can be linked to a caregiver call button or a display screen of a terminal device used by a caregiver. This makes it easier for the user to properly determine the replacement time of the absorbent pad 1 or the like. However, it is not necessarily necessary to perform the alarm (S109).

[0125] On the other hand, if the change amount of the capacitance value C11 is smaller than the predetermined size in S103 (No in S103), the process proceeds to step S106. The case where the change amount of the capacitance value C11 is smaller than the predetermined size means a state where the pair of skin-side electrodes 11 and 11 is not conducted. That is, in S102, the pair of non-skin-side electrodes 12 and 12 is conducted, and in S103, the pair of skin-side electrodes 11 and 11 is not conducted.

[0126] In this case, the detection device 50 (information processing apparatus 60) determines that a small amount of urine has been excreted (S106). If the amount of excreted urine is small, there is a case where only the non-skin-side electrode 12 facing the absorbent body 21 is in contact with the urine, that is, the case where the non-skin-side electrodes 12 and 12 are conducted. In this case, it is determined that a small amount of urine has been excreted.

[0127] If it is determined that urination has occurred (a small amount) in S106, the detection device 50 issues a reminder (an alarm) for notifying the user (wearer or caregiver thereof) that a small amount of urination has occurred (S110). This alarm can be performed in substantially the same manner as in S109, but it is recommended to use a different reminder sound or a different screen display, which makes it easier for the user to recognize the amount of excreted urine.

[0128] Next, the detection of defecation will be described. Returning to Figure 8If the change amount of the capacitance value C12 between the non-skin side electrodes 12 and 12 is smaller than the predetermined size (NO at S102), the detection device 50 determines the change amount of the capacitance value C11 based on the detection result of the skin side capacitance detection process for a predetermined period of time (S104). As a result, if the case is that the change amount of the capacitance value C11 is equal to or larger than the predetermined size (YES at S104), the process proceeds to step S107. The case that the change amount of the capacitance value C11 is equal to or larger than the predetermined size means the state that the pair of skin side electrodes 11 and 11 is conducted. That is, it means the state that the pair of non-skin side electrodes 12 and 12 is not conducted in S102 and the pair of skin side electrodes 11 and 11 is conducted in S103.

[0129] As shown in Figure 7 A and Figure 7 B, only the skin side electrode 11 is conducted and the non-skin side electrode 12 is not conducted, which indicates that the feces has been excreted into the absorbent pad 1. Therefore, in this case, the detection device 50 determines that the defecation has been performed (S107).

[0130] If the defecation is determined in S107, the detection device 50 issues a reminder (an alarm) for notifying the user (the wearer or the caregiver) that the defecation has been performed (S111). This alarm can be performed in substantially the same manner as S109 and S110. However, it is recommended to use a different reminder sound or a different picture display, which makes it easier for the user to recognize that the excrement is feces and it will be necessary to replace the absorbent pad 1.

[0131] On the other hand, in S104, if the change amount of the capacitance value C11 is smaller than the predetermined size (NO at S104), the process proceeds to step S108. The case that the change amount of the capacitance value C11 is smaller than the predetermined size means the state that the moisture such as urine does not reach between the pair of skin side electrodes 11 and 11 and does not cause the electrodes to be conducted. That is, it means the state that the pair of non-skin side electrodes 12 and 12 is not conducted and the pair of skin side electrodes 11 and 11 is not conducted.

[0132] The reason that neither the skin side electrode 11 nor the non-skin side electrode 12 is conducted is that no excretion is performed at all or the amount of excretion is extremely small, to the extent that the excrement is not detected in each of the electrodes. Therefore, in this case, the detection device 50 determines that the excretion has not been performed (S108). It should be noted that if the amount of excretion is small, the absorbency of the absorbent pad 1 (the absorbent body 2) is hardly affected, and thus, even when it is determined that the excretion has not been performed, it is less likely to cause a problem. In addition, if it is determined that the excretion has not been performed, no alarm or the like is issued, which does not disturb the user.

[0133] As described above, in the absorbent pad 1, based on the amount of change in the data (capacitance values C11 and C12) detected from the skin-side electrode 11 and the non-skin-side electrode 12 over a predetermined period of time, it is possible to determine whether the excretion is feces or urine with high accuracy. Further, when urine has been excreted, it is possible to determine the amount of excretion. Thereby, the user can appropriately determine the replacement time of the absorbent pad 1 without the trouble of opening and checking the diaper 101 (absorbent article) used by the wearer every time excretion occurs.

[0134] Second Embodiment

[0135] In the second embodiment, a method of determining excretion (determining whether the excretion is urine or feces) with high accuracy using the absorbent pad 1 described in the first embodiment will be described. It should be noted that the configuration of the device including the absorbent pad 1 (see Figures 1 to 5 ) and the principle of detecting excretion by the electrodes 11 and 12 (see Figures 6 to 7 ) are the same as those of the first embodiment, and thus the description thereof will be omitted.

[0136] Method for detecting excretion

[0137] Figure 9 is a flowchart showing an example of the excretion / urination determination process using the absorbent pad 1 in the second embodiment. When starting to detect excretion, the detection device 50 intermittently applies a current to each of the electrodes 11 and 12 of the absorbent pad 1. Then, the following detection processes are performed: a non-skin-side capacitance detection process that detects the magnitude of the capacitance value C12 between the non-skin-side electrodes 12 and 12; and a non-skin-side resistance detection process that detects the magnitude of the resistance value R12 between the non-skin-side electrodes 12 and 12. Further, the following detection processes are performed: a skin-side capacitance detection process that detects the magnitude of the capacitance value C11 between the skin-side electrodes 11 and 11; and a skin-side resistance detection process that detects the magnitude of the resistance value R11 between the skin-side electrodes 11 and 11 (S201).

[0138] Next, in the same manner as S102 to S104 of the first embodiment, the detection device 50 determines the amount of change in the capacitance value C12 and the capacitance value C11 detected by each set of electrodes 11 and 12 over a predetermined period of time (S202 to S204). The contents of the determination are the same as those determined in the first embodiment.

[0139] In Figure 9In the case where S203 determines YES, that is, in the case where the change amounts of the capacitance value C12 and the capacitance value C11 are equal to or greater than the predetermined value, the detection device 50 determines whether a predetermined time difference is generated between the time when the capacitance value C12 changes and the time when the capacitance value C11 changes (S205). For example, it is determined whether a predetermined time (for example, 0.5 seconds) elapses between the time when the capacitance value C11 starts to change and the time when the capacitance value C12 starts to change.

[0140] Similarly to the case described in S103 of the first embodiment, in the case where S203 determines YES, the possibility that urination is performed on the absorbent pad 1 is high. Here, if urine has been excreted on the skin side surface of the absorbent body 2, a predetermined time difference should be generated until the urine penetrates into the absorbent body 2 from the skin side to the non-skin side. That is, after a predetermined time elapses from the time when the urine comes into contact with the skin side electrode 11 of the skin side of the absorbent body 2, the urine excreted in the absorbent pad 1 should come into contact with the non-skin side electrode 12 of the non-skin side of the absorbent body 2.

[0141] Therefore, if there is no predetermined time difference between the time when the capacitance value C12 changes and the time when the capacitance value C11 changes, that is, if the capacitance values C12 and C11 both change at the same time (NO in S205), the behavior is different from the normal urination behavior. In this case, the detection device 50 determines that the changes in the capacitance values C11 and C12 are noise, and determines that no urination is performed (S208).

[0142] For example, even if no urination is performed, when the wearer moves the body, the capacitance values C11 and C12 can change at the same time due to the wearer's body weight being temporarily applied to the skin side electrode 11 and the non-skin side electrode 12 (the wearer's skin is pressed). When a urination is determined based on this detection result, there is a high possibility that a false determination is made. Therefore, if a behavior different from the normal urination behavior is detected, the detection device 50 does not determine that a urination is performed and processes the detection result as noise. This makes it possible to improve the detection accuracy of urination and suppress false determinations.

[0143] On the other hand, if a predetermined time difference is generated between the time when the capacitance value C12 changes and the time when the capacitance value C11 changes (YES in S205), it is considered to be a behavior in normal urination, and the processing proceeds to step S207.

[0144] In S207, the detection device 50 determines whether the resistance value Rll detected between the skin-side electrodes 11 and 11 returns to the original size within a predetermined period of time (S207). For example, when urination has been performed, the detected value of the resistance value Rll decreases, and after a predetermined time (for example, 5 minutes) elapses, it is determined whether the resistance value Rll returns from the minimum value of the detected value that has decreased when urination has been performed to, for example, about 20%.

[0145] When urination has been performed, the urine discharged on the skin-side surface of the absorbent body 2 is absorbed by the absorbent body 2 over time. Therefore, immediately after urination, the resistance value Rll decreases due to conduction between the pair of skin-side electrodes 11 and 11. However, when the urine is absorbed by the absorbent body 2 after a predetermined time elapses, the region between the pair of skin-side electrodes 11 and 11 again enters a non-conductive state, and the resistance value Rll returns to its original size (the resistance value Rll recovers). Therefore, the degree of such recovery of the resistance value Rll can be used as an additional index for determining urination.

[0146] In S207, if the resistance value Rll does not recover after a predetermined time elapses (No in S207), this is a behavior different from that in normal urination. In this case, the detection device 50 determines the change in the resistance value Rll to be noise and determines that urination has not been performed (S209).

[0147] Similar to the case described in S208, even if urination has not been performed, when the wearer moves the body, the skin-side electrodes 11 can be conductive due to the weight of the wearer being applied to the skin-side electrodes 11 (the skin of the wearer being pressed), and the resistance value Rll decreases, and remains and does not recover. When a determination of urination is made based on this detection result, there is a high possibility of a false determination being made. Therefore, if a behavior different from that in normal urination is detected as described above, the detection device 50 processes the detection result as noise. This makes it possible to improve the detection accuracy of urination.

[0148] On the other hand, if the resistance value Rll recovers after a predetermined time elapses (Yes in S207), this is considered to be a behavior of normal urination, and the detection device 50 determines that urination has been performed (S210).

[0149] If urination is determined in S210, the detection device 50 issues a reminder (an alarm) for notifying the user (the wearer or a caregiver) that urination has been performed (S215). The alarm can be performed in substantially the same manner as described in S109 of the first embodiment.

[0150] Returning to Figure 9If the amount of change in the capacitance value Cll between the skin-side electrodes 11 and 11 is smaller than the predetermined size (NO in S203), the detection device 50 determines that a small amount of urine has been excreted (S206). The reason is the same as described in S106 of the first embodiment.

[0151] If it is determined that urination (small amount) has been performed in S206, the detection device 50 issues a reminder (alarm) for notifying the user (wearer or his or her caregiver) that a small amount of urination has been performed (S216). The alarm can be performed in substantially the same manner as in S215, but it is recommended to use a different reminder sound or a different picture display, which makes it easier for the user to recognize the amount of excreted urine.

[0152] Next, the detection of defecation will be described. Returning to Figure 9 If the amount of change in the capacitance value Cll between the skin-side electrodes 11 and 11 is equal to or larger than the predetermined size (YES in S204), the detection device 50 determines whether the capacitance value Cll returns to the original size within a predetermined period (S211). For example, when defecation has been performed, the detected value of the capacitance value Cll increases, but after a predetermined time (for example, 60 seconds) elapses, it is determined whether the capacitance value Cll returns to about 120% of the original size.

[0153] If defecation has been performed, the feces excreted on the skin-side surface of the absorbent body 2 is unlikely to be absorbed by the absorbent body 2. Therefore, the feces continues to remain on the skin-side surface even after a period of time elapses. Therefore, since the current immediately passes between the pair of skin-side electrodes 11 and 11 after defecation, the capacitance value Cll is unlikely to change even after a predetermined time elapses after the capacitance value Cll increases. That is, if defecation has been performed, the size of the capacitance value Cll is unlikely to return. Therefore, the degree of return of this capacitance value Cll can be used as an additional index for determining defecation.

[0154] In S211, if the capacitance value Cll returns after a predetermined time elapses (YES in S211), this behavior is different from that in normal defecation. In this case, the detection device 50 determines the change in the capacitance value Cll as noise and determines that defecation has not been performed (S213).

[0155] On the other hand, if the capacitance value Cll has not returned even after a predetermined time elapses (NO in S211), it is considered to be a behavior in normal defecation, and the detection device 50 determines that defecation has been performed (S214).

[0156] Then, if it has been determined that defecation in S214, the detection device 50 issues a reminder (alarm) for notifying the user (wearer or his or her caregiver) that defecation has been performed (S217).

[0157] Further, in a case where the amount of change in the capacitance value C11 between the skin-side electrodes 11 and 11 is smaller than the predetermined size in S204 (No in S204), it means a state where the pair of non-skin-side electrodes 12 and 12 are conducted and the pair of skin-side electrodes 11 and 11 are conducted. In this case, the detection device 50 determines that no excretion is performed (S212). As described in S108 of the first embodiment, this is because the phenomenon that both the skin-side electrodes 11 and the non-skin-side electrodes 12 are not conducted indicates that no excretion is performed at all or the amount of excretion is extremely small to the extent that no excretion is detected in each of the electrodes.

[0158] As described above, in the second embodiment, the timing at which the capacitance values C11 and C12 and the resistance values R11 and R12 change and the amount of change (degree of recovery) after a predetermined time elapses are used as indexes for determining excretion. Therefore, the data detected under the predetermined conditions can be removed as noise, and excretion can be determined more accurately.

[0159] Other Embodiments

[0160] Although the above embodiments of the present application have been described, the above embodiments are intended to facilitate the understanding of the present application and are not intended to limit the explanation of the present application. Further, it goes without saying that the present application can be modified or improved without departing from the gist of the present application, and the present application includes equivalents thereof.

[0161] In the above embodiments, the non-skin-side electrodes 12 are formed by applying the conductive ink in a belt-like pattern to the surface of the base sheet 122, but another configuration is also acceptable. For example, the non-skin-side electrodes 12 can be formed by directly applying the conductive ink to the skin-side surface of the leakage prevention sheet 4 disposed on the non-skin-side surface of the absorbent body 2. That is, the leakage prevention sheet 4 can have the function of the base sheet 122. The leakage prevention sheet 4 itself is a liquid-impermeable sheet member, and thus even in this configuration, the excretion can be detected in the same manner as in the case where the base sheet 122 is separately provided. With the above configuration, it is not necessary to separately prepare the base sheet 122, and the manufacturing steps can be simplified. Therefore, the manufacturing cost can be reduced.

[0162] List of Reference Signs

[0163] 1: Absorbent pad (absorbent article),

[0164] 2: Absorbent body,

[0165] 21: Absorbent core, 21A: Skin-side core layer, 21B: Non-skin-side core layer,

[0166] 22: core wrap sheet,

[0167] 3: front sheet (liquid-permeable sheet),

[0168] 4: leakage barrier sheet (liquid-impermeable sheet),

[0169] 5: back sheet (outer cover sheet),

[0170] 10: electrode,

[0171] 11: skin-side electrode,

[0172] 111: conductive portion, 112: base sheet (liquid-impermeable sheet member), 113: cover portion,

[0173] 12: non-skin-side electrode,

[0174] 121: conductive portion, 122: base sheet (liquid-impermeable sheet member), 123: cover portion,

[0175] 50: detection device,

[0176] 51: main unit, 52: connection unit, 53: data transmission and reception unit,

[0177] 60: information processing apparatus,

[0178] 101: diaper (disposable diaper, absorbent article),

[0179] 111: absorbent core, 121: surface sheet, 131: back sheet, 141: fastening belt

Claims

1. An absorbent article having a longitudinal direction, a width direction, and a thickness direction intersecting each other in an extended state, the absorbent article comprising: a liquid-absorbing absorbent; a liquid-permeable sheet disposed on a skin side in the thickness direction with respect to the absorbent; a liquid-impermeable sheet disposed on a non-skin side in the thickness direction with respect to the absorbent; a skin-side electrode between the liquid-permeable sheet and the absorbent; and a non-skin-side electrode between the liquid-impermeable sheet and the absorbent, the skin-side electrode and the non-skin-side electrode each comprising: a conductive portion; and a liquid-impermeable sheet member disposed so as to be superimposed on the conductive portion in the thickness direction, a liquid-impermeable region being provided in at least a portion of each of the skin-side electrode and the non-skin-side electrode on a side in the thickness direction opposite to a side on which the liquid-impermeable sheet member is disposed, at least one pair of the non-skin-side electrodes being disposed so as to be spaced apart from each other at a predetermined distance in the width direction, at least one pair of the skin-side electrodes being disposed so as to be spaced apart from each other at a distance different from the predetermined distance in the width direction, the spacing in the width direction between a pair of the skin-side electrodes being greater than the spacing in the width direction between a pair of the non-skin-side electrodes.

2. The absorbent article according to claim 1, wherein the spacing in the width direction between a pair of the skin-side electrodes is 40 mm or greater.

3. The absorbent article according to claim 1 or 2, wherein the spacing in the width direction between a pair of the non-skin-side electrodes is 40 mm or greater.

4. The absorbent article according to claim 1 or 2, wherein presence / absence of excretion is detected based on contact of each of the skin-side electrode and the non-skin-side electrode with excretion.

5. The absorbent article according to claim 1 or 2, wherein the skin-side electrode and the non-skin-side electrode each include the liquid-impermeable sheet member on the same side in the thickness direction.

6. The absorbent article according to claim 5, wherein the skin-side electrode and the non-skin-side electrode each include the liquid-impermeable sheet member on the non-skin side in the thickness direction.

7. The absorbent article according to claim 1 or 2, wherein a width of the liquid-impermeable sheet member is greater than a width of the skin-side electrode and the non-skin-side electrode.

8. The absorbent article according to claim 1 or 2, wherein in the longitudinal direction, an area of the liquid-impermeable region with respect to the front side from the center is greater than an area of the liquid-impermeable region with respect to the back side from the center.

9. The absorbent article according to claim 1 or 2, wherein a thickness of the liquid-permeable sheet is thicker than a thickness of the skin-side electrode and the non-skin-side electrode.

10. The absorbent article according to claim 1 or 2, wherein ​ ​ End portions of the skin-side electrode and the non-skin-side electrode in the longitudinal direction of the skin-side electrode and the non-skin-side electrode are positioned outside at least one of a ventral end and a dorsal end of the absorbent body in the longitudinal direction.

11. A defecation / urination determination method using an absorbent article, The absorbent article includes: a liquid-absorbing absorbent body; a liquid-permeable sheet arranged on a skin side in a thickness direction with respect to the absorbent body; and a liquid-impermeable sheet arranged on a non-skin side in the thickness direction with respect to the absorbent body, The method includes: a skin-side capacitance detection process that detects a size of a capacitance by a skin-side electrode provided between the liquid-permeable sheet and the absorbent body; a non-skin-side capacitance detection process that detects a size of a capacitance by a non-skin-side electrode provided between the liquid-impermeable sheet and the absorbent body; and a determination process that determines whether excrement that has been excreted on the absorbent article is feces or urine based on an amount of change in the capacitance detected by the skin-side capacitance detection process over a predetermined period of time and an amount of change in the capacitance detected by the non-skin-side capacitance detection process over the predetermined period of time, The skin-side electrode and the non-skin-side electrode each include: a conductive portion; and a liquid-impermeable sheet member arranged to be superimposed on the conductive portion in the thickness direction, a liquid-impermeable region being provided on a side opposite to a side on which the liquid-impermeable sheet member is provided in the thickness direction in at least a portion of each of the skin-side electrode and the non-skin-side electrode, at least one pair of the non-skin-side electrodes is arranged to be spaced apart from each other at a predetermined distance in a width direction of the absorbent article, at least one pair of the skin-side electrodes is arranged to be spaced apart from each other at a distance different from the predetermined distance in the width direction, a distance between a pair of the skin-side electrodes in the width direction is greater than a distance between a pair of the non-skin-side electrodes in the width direction.

12. The defecation / urination determination method according to claim 11, if the amount of change in the capacitance detected by the skin-side electrode over the predetermined period of time is equal to or greater than a predetermined value, and if the amount of change in the capacitance detected by the non-skin-side electrode over the predetermined period of time is equal to or greater than the predetermined value, urine is determined to have been excreted, and if the amount of change in the capacitance detected by the skin-side electrode over the predetermined period of time is equal to or greater than the predetermined value, and if the amount of change in the capacitance detected by the non-skin-side electrode over the predetermined period of time is less than the predetermined value, feces is determined to have been excreted.

13. The defecation / urination determination method according to claim 12, with respect to a timing at which the capacitance detected by the skin-side electrode changes over the predetermined period of time, and with respect to a timing at which the capacitance detected by the non-skin-side electrode changes over the predetermined period of time, a difference between these timings is used as an additional index for determining urination. ​ 14. The defecation / urination determination method according to claim 13, characterized in that, the time at which the change in the capacitance detected by the skin-side electrode within the predetermined period of time, and the time at which the change in the capacitance detected by the non-skin-side electrode within the predetermined period of time, in the case where these times are the same, this case is determined to be noise.

15. The defecation / urination determination method according to any one of claims 12 to 14, characterized in that, the method further includes a skin-side resistance detection process that detects the magnitude of a resistance value by the skin-side electrode, and the degree of recovery after the change in the resistance value detected by the skin-side electrode within the predetermined period of time, the degree is used as an additional index for determining urination.

16. The defecation / urination determination method according to any one of claims 12 to 14, characterized in that, the degree of recovery after the change in the capacitance value detected by the skin-side electrode within the predetermined period of time, the degree is used as an additional index for determining defecation.

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