Wet detection sensor sheet, wet detection sensor sheet kit, and wet detection system

Abstract

The invention provides a soak detection sensor sheet, a soak detection sensor sheet kit, and a soak detection system. A wetting detection sensor sheet configured so as to be worn by a wearer as a part of an absorbent article or so as to be worn by the wearer together with the absorbent article, the wetting detection sensor sheet being provided with: a sheet-like sensor unit configured so as to include an antenna unit and a communication unit and so as to be capable of wireless communication; and a water-guiding sheet that is disposed so as to overlap on one side or both sides of the sensor unit, and that is configured so as to extend from the abdomen side of the wearer to the back side via the crotch section when the wearer wears the absorbent article. The sensor unit is provided closer to a region corresponding to the abdomen side or a region corresponding to the back side in the water guide sheet than a region corresponding to the crotch part in the water guide sheet.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of Japanese Patent Application No. 2024-037999 filed with the Japan Patent Office on March 12, 2024, which is hereby incorporated by reference herein in its entirety. Technical Field

[0001] The present invention relates to a wetness detection sensor sheet, a wetness detection sensor sheet kit and a wetness detection system. Background Art

[0002] A sensor having a wireless communication function and capable of detecting wetting of an absorbent article such as a diaper is known. Japanese Patent Application Laid-Open No. 2021-38971 discloses a liquid detection sensor including: a sheet substrate formed of a material that deforms in response to liquid; an antenna formed on the sheet substrate; and a communication circuit connected to the antenna for wireless communication via the antenna. Japanese Patent Publication No. 2020-165653 discloses a urination detection tag comprising: a hygroscopic substrate; a ring-shaped wiring formed on the substrate and having a disconnection portion in a portion; a communication antenna formed on the substrate; and a detection device connected to the wiring and the communication antenna, detecting the conductive state of the wiring and transmitting the detection result contactlessly via the communication antenna.

[0003] In the liquid detection sensor disclosed in Japanese Patent Application Laid-Open No. 2021-38971, the antenna formed on the sheet substrate deforms due to reaction with liquid, causing a characteristic change or breakage. This characteristic change or breakage is detected by the wireless communication device, thereby detecting diaper wetting. Therefore, this liquid detection sensor needs to be placed in the crotch of the diaper wearer to ensure that urination reliably reaches the sheet substrate. The same is true for the urination detection tag disclosed in Japanese Patent Application Laid-Open No. 2020-165653, which envisions the liquid detection sensor being placed in the crotch of the diaper wearer. However, when the liquid detection sensor is disposed in the crotch portion, there is a problem that not only the wearer feels uncomfortable due to the foreign body sensation, but also the wireless communication direction of the liquid detection sensor is limited. Summary of the Invention

[0004] An embodiment of the present invention relates to a wetness detection sensor sheet, which is configured to be worn by a wearer as a part of an absorbent article or to be worn by the wearer together with the absorbent article. The wetness detection sensor sheet includes a sheet-shaped sensor portion and a water guide sheet. The sensor portion is configured to include an antenna portion and a communication portion and is capable of wireless communication. The water guide sheet is overlapped and arranged on one side or both sides of the sensor portion and is configured to extend from the abdomen side of the wearer through the crotch portion to the back side when the wearer wears the absorbent article. The sensor portion is configured to be arranged on the side of the area corresponding to the abdomen side or the area corresponding to the back side of the water guide sheet than the area corresponding to the crotch portion of the water guide sheet.

[0005] One of the present inventions has been made in view of such circumstances, and provides a wetness detection sensor sheet, a wetness detection sensor sheet kit, and a wetness detection system that provide a good wearing feel and can reliably detect wetness of an absorbent article.

[0006] The present invention relates to a wetness detection sensor sheet, which is configured to be worn by a wearer as a part of an absorbent article or to be worn by the wearer together with the absorbent article. The wetness detection sensor sheet includes a sheet-shaped sensor portion and a water guide sheet. The sensor portion is configured to include an antenna portion and a communication portion and is capable of wireless communication. The water guide sheet is overlapped and arranged on one side or both sides of the sensor portion, and is configured to extend from the abdomen side of the wearer through the crotch portion to the back side when the wearer wears the absorbent article. The sensor portion is arranged on the side of the area corresponding to the abdomen side or the area corresponding to the back side of the water guide sheet than the area corresponding to the crotch portion of the water guide sheet.

[0007] In addition, the wetness detection sensor sheet kit of the present invention includes multiple wetness detection sensor sheets of the present invention, and the water absorption components of the multiple wetness detection sensor sheets contained in the wetness detection sensor sheet kit are constructed so that the amount of water absorption that causes the antenna part or the wire part of the sensor part to become the disconnected state is different.

[0008] In addition, the wetting detection system of the present invention is capable of wirelessly communicating with the wetting detection sensor sheet of the present invention. The wetting detection system includes a terminal communication unit, a judgment unit, a display processing unit and a display unit. The terminal communication unit is configured to include an antenna and is capable of wirelessly communicating with the sensor unit through the antenna. The judgment unit is configured to judge whether the absorbent article is wet based on the wireless communication status between the terminal communication unit and the sensor unit. When the wireless communication status represents a specific wireless communication status corresponding to the disconnected state of the sensor unit, the display processing unit causes the display unit to display an alarm display regarding the relationship between the position of the antenna relative to the absorbent article and the position of the sensor unit relative to the absorbent article. The judgment unit judges whether the absorbent article is wet based on the user operation on the alarm display.

[0009] In addition, the wetness detection system of the present invention includes a terminal communication unit, a determination unit, an information management unit and an information storage unit of the present invention, wherein the terminal communication unit is configured to be able to communicate wirelessly with the sensor unit, the determination unit is configured to determine whether the absorbent article is wet based on the wireless communication status between the terminal communication unit and the sensor unit, the information storage unit is configured to store wearer identification information, wearing time information, sensor identification information, and position information of the sensor unit in the absorbent article for each wearer of the absorbent article, the sensor unit having sensor identification information, the terminal communication unit is configured to be able to obtain the sensor identification information from the sensor unit through wireless communication, the information management unit determines the wearer identification information of the wearer specified by user operation when the absorbent article is worn, and causes the terminal communication unit to obtain the sensor identification information from the sensor unit, associate the sensor identification information with the determined wearer identification information, and store the obtained sensor identification information, the wearing time information, and the position information of the sensor unit in the absorbent article in the information storage unit.

[0010] According to the present invention, it is possible to provide a wetness detection sensor sheet, a wetness detection sensor sheet kit, and a wetness detection system that provide a comfortable wearing feeling and can reliably detect wetness of an absorbent article. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a plan view showing an example of attaching the wetness detection sensor sheet according to the present embodiment to an absorbent article. Figure 2 It is a diagram schematically showing the stacked structure of the wetness detection sensor sheet according to the present embodiment. Figure 3 This is a partial cross-sectional view of the sensor section. Figure 4 This is a plan view of the sensor unit when viewed from the wearer's side. Figure 5 This is a diagram selectively showing the antenna portion, the lead portion, and the communication portion of the sensor portion when viewed from the wearer's side. Figure 6 This is a diagram selectively showing the lead wire portion in the sensor portion when viewed from the wearer's side. Figure 7 This is a diagram conceptually showing the hardware configuration of the wetness detection system. Figure 8 This is a diagram conceptually showing the software structure of the wetness detection system. Figure 9 It is a diagram showing an example of a wearer information table stored in a wearer management database. Figure 10 This is a flowchart showing an example of the operation of the wetness detection system during wetness confirmation. Figure 11 This is a flowchart showing an example of the operation of the wetness detection system when the absorbent article is worn or replaced. DETAILED DESCRIPTION In the following detailed description, for purposes of illustration, numerous specific details are set forth to provide a thorough understanding of the disclosed embodiments. However, it will be apparent that one or more embodiments may be practiced without these specific details. In other instances, well-known structures and devices are schematically shown to simplify the drawings.

[0012] The following describes embodiments of the present invention. However, the following embodiments are merely illustrative, and the present invention is not limited to the configurations of the following embodiments.

[0013] First, the outline of the structure of the wetness detection sensor sheet (hereinafter sometimes referred to as a sensor sheet) according to the present embodiment will be described. The sensor sheet is worn as a part of an absorbent article or together with an absorbent article to detect wetting of the absorbent article. "Absorbent articles" are articles that can absorb liquids, such as disposable diapers, urine-removing pads, sanitary napkins, panty liners, and pet potty pads. However, the absorbent articles for which wetting is detected by the sensor sheet are not limited to these examples. The "wearer" refers to a person or animal (pet) who wears the absorbent article or the present sensor sheet.

[0014] The sensor sheet can be pre-assembled into an absorbent article as part of the absorbent article, or it can be formed separately from the absorbent article and attached to the absorbent article during use. For example, if the absorbent article is a urine-collecting pad, the sensor sheet can be housed inside the pad, or it can be attached to the surface of the pad (the side facing the wearer when the absorbent article is worn) so that it is within the pad's surface when viewed from above, or between the back of the pad and underwear or a diaper.

[0015] This sensor sheet includes at least a sheet-shaped sensor portion and a water guide sheet. The water-guiding sheet is disposed overlappingly on one or both sides of the sensor portion and is configured to extend from the wearer's abdomen through the crotch portion to the back when the absorbent article is worn. Preferably, the water-guiding sheet is configured to extend from a specific location on the wearer's abdomen through the crotch portion to a specific location on the back when the absorbent article is worn. The "abdominal specific site" refers to a specific site on the wearer's abdomen that is closer to the crotch than the wearer's lower abdomen, and is any location on the lower abdomen below the navel. For example, the abdominal specific site is near the bladder. The "specific back area" refers to a specific area on the back of the wearer, further from the crotch, and can be any location on the buttocks. For example, the specific back area is near the sacrum. The water-guiding sheet is preferably long enough to cover the area from the bladder through the crotch to the sacrum on the body surface of an average-sized adult.

[0016] The sensor unit is configured to include an antenna unit and a communication unit, and can cause the detection device to detect wetting of the absorbent article through wireless communication. The communication unit is a circuit for transmitting radio waves of a predetermined frequency from the antenna unit, and includes, for example, an IC chip for an RFID tag. The communication unit may also include a power supply, but preferably does not include a power supply for cost reduction. When viewed from above, the sensor portion is positioned closer to the abdomen or back side of the water guide sheet in the longitudinal direction than the area corresponding to the wearer's crotch. Specifically, the sensor portion is positioned in an area closer to the abdomen or back end than the crotch area corresponding to the wearer's crotch. The area closer to the abdomen than the crotch area refers to the interior of the abdomen, and the area between the crotch area and the abdomen in the longitudinal direction, and closer to the abdomen. The same is true for the back end; the area closer to the back end than the crotch area refers to the interior of the back end, and the area between the crotch area and the back end, and closer to the back end. The crotch region of the water guide sheet is a region of the water guide sheet located at the crotch of the wearer and has a predetermined width in the width direction and longitudinal direction of the water guide sheet so as to cover the crotch of the wearer. The abdominal end portion and the back end portion of the water guide plate are both ends in the longitudinal direction of the water guide plate, and are regions encompassing a certain range from each end in the longitudinal direction. The abdominal end portion and the back end portion do not overlap with the crotch region.

[0017] Thus, in this sensor sheet, the sensor portion is arranged in an area of ​​the water guide sheet that is closer to the abdomen side end or the back side end in the long side direction than the crotch area when viewed from above, and the water guide sheet is arranged to extend from a specific part of the wearer's abdomen side through the crotch part to a specific part of the back side. Therefore, since the sensor portion is located at a position closer to the abdomen or back side of the wearer than the crotch portion when the absorbent article is worn, the range of wireless communication between the sensor portion and the detection device can be expanded compared to the case where the sensor portion is located at the crotch portion, and the foreign body sensation and discomfort caused by the sensor portion can be reduced for the wearer. In addition, by using a water-guiding sheet extending from a specific portion of the wearer's abdomen to a specific portion of the back, liquid discharged from the wearer, such as urination, can reliably reach the sensor portion regardless of the wearer's gender or body position, thereby reliably detecting wetting of the absorbent article.

[0018] The following describes the details of the wetness detection sensor sheet of the present invention. In the following embodiments, the absorbent article is a urine-collecting pad, and the wetness detection sensor sheet is attached to the surface of the urine-collecting pad (the surface facing the wearer when the absorbent article is worn). In the following description, the positions and orientations of the various components of the wetness detection sensor sheet and the absorbent article refer to those when the absorbent article is properly worn. Specifically, the side that contacts the wearer's skin is sometimes referred to as the "wearer side," the opposite side is sometimes referred to as the "outer side," the left-right direction of the wearer is sometimes referred to as the "left-right direction," and the front-back direction of the wearer is sometimes referred to as the "front-back direction."

[0019] [Wet detection sensor sheet] Figure 1 This is a plan view showing an example of attaching the wetness detection sensor sheet 1 (hereinafter sometimes referred to as the sensor sheet 1 ) according to this embodiment to an absorbent article. exist Figure 1 In the example of FIG, the sensor sheet 1 is attached to a urine collecting pad 50 as an absorbent article. Figure 1 The sensor sheet 1 and the wearer-side surface of the urine-absorbing pad 50 are shown in FIG.

[0020] The urine-collecting pad 50 includes an abdominal portion 51, a rear portion 52, and a connecting portion 53 connecting the abdominal portion 51 and the rear portion 52. The urine-collecting pad 50 is attached to the wearer's side of underwear or a diaper, with the abdominal portion 51 positioned on the wearer's abdominal side, the rear portion 52 positioned on the wearer's rear side, and the connecting portion 53 positioned in the wearer's crotch. Because the connecting portion 53 is positioned in the wearer's crotch, it is narrower than the abdominal portion 51 and the rear portion 52.

[0021] The urine pad 50 has an absorber 55 on the wearer's side. The absorber 55 is configured to absorb liquids discharged from the wearer, such as urine. The absorber 55 extends in the front-to-back direction (longitudinal direction) across the abdominal portion 51, the back portion 52, and the connecting portion 53. Furthermore, the urine pad 50 has a pair of three-dimensional pleats 57 extending in the longitudinal direction of the absorber 55 at both ends of the absorber 55 in the left-right direction (width direction). These three-dimensional pleats 57 suppress leakage in the width direction of the urine pad 50.

[0022] The sensor sheet 1 is mounted on the wearer side of the absorber 55 so as to be housed within the surface of the absorber 55 and extend from one end of the absorber 55 in the longitudinal direction (the end of the abdomen side portion 51) to the other end (the end of the back side portion 52). In addition, Figure 1 In the example of FIG, as shown by the dotted line, the sensor portion 10 of the sensor sheet 1 is arranged on the abdomen side portion 51 of the urine collecting pad 50. Figure 1 In the example of FIG. 5 , the sensor portion 10 is provided so as to be located on the bladder on the abdomen side of the wearer when the absorbent article is worn.

[0023] When the urine pad 50 is worn with the sensor sheet 1 attached, after the wearer urinates, urine passes through the sensor sheet 1 and is absorbed by the absorbent body 55 of the urine pad 50. The urine is then directed by the sensor sheet 1 to the sensor portion 10. As a result, a detection device (not shown) communicating wirelessly with the sensor portion 10 can detect the wetting of the urine pad 50. In other words, the sensor sheet 1 can detect the wetting of an absorbent article such as the urine pad 50 and can be used as a urination sensor to notify a caregiver when the absorbent article should be replaced.

[0024] However, the urine collecting pad 50 equipped with the sensor sheet 1 is not limited to Figure 1 The sensor sheet 1 can be used together with urine-collecting pads of various structures having an absorbent body 55. In addition, the absorbent article provided with the sensor sheet 1 is not limited to urine-collecting pads, and as mentioned above, it may also be a disposable diaper or the like. In addition, Figure 1In the example shown in FIG. 1 , the sensor portion 10 is provided on the abdomen side portion 51 in the sensor sheet 1 , but may be provided on the back side portion 52 .

[0025] Next, the detailed structure of the sensor sheet 1 will be described. Figure 2 It is a diagram schematically showing the laminated structure of the wetness detection sensor sheet 1 (sensor sheet 1 ) according to the present embodiment.

[0026] The sensor sheet 1 is a laminated body formed into a flat plate. It is constructed by stacking, in order from the wearer's side toward the outside, a wearer-side water-permeable sheet 2, a water-guiding sheet 4, a water-absorbent sheet 5, a water-swellable material 6, a sheet-shaped sensor portion 10, an outer water-permeable sheet 3, and a displacement prevention sheet 7. More specifically, in the sensor sheet 1, the stacked water-guiding sheet 4, water-absorbent sheet 5, water-swellable material 6, and sensor portion 10 are sandwiched between the wearer-side water-permeable sheet 2 and the outer water-permeable sheet 3. The displacement prevention sheet 7 is provided on the outer water-permeable sheet 3's surface opposite the water-guiding sheet 4 (outer side).

[0027] The outer shapes of the wearer-side water-permeable sheet 2 and the outer side water-permeable sheet 3 are identical to each other and coincide with each other in a plan view, forming the outer shape of the sensor sheet 1 . In addition, on the surface of the wearer-side water-permeable sheet 2 opposite to the wearer's side ( Figure 2 The lower surface of the wearer side water-permeable sheet 2 in the middle) and the wearer side surface of the outer water-permeable sheet 3 ( Figure 2 An adhesive or pressure-sensitive adhesive (not shown) is applied to at least one of the wearer-side water-permeable sheet 2 and the outer water-permeable sheet 3 (the upper surface of the outer water-permeable sheet 3). The peripheral edges of the wearer-side water-permeable sheet 2 and the outer water-permeable sheet 3 are joined together by pressure bonding. Alternatively, the wearer-side water-permeable sheet 2 and the outer water-permeable sheet 3 can be joined together by heat-welding. Thus, the water guide sheet 4, water absorbent sheet 5, water-swellable member 6, and sensor portion 10, which are laminated between the wearer-side water-permeable sheet 2 and the outer water-permeable sheet 3, are constrained by the wearer-side water-permeable sheet 2 and the outer water-permeable sheet 3. Specifically, the water guide sheet 4, water absorbent sheet 5, water-swellable member 6, sensor portion 10, and displacement prevention sheet 7 have a shape and size that fit within the plane of the wearer-side water-permeable sheet 2 and the outer water-permeable sheet 3 when viewed from above.

[0028] The wearer-side water-permeable sheet 2 and the outer water-permeable sheet 3 can be made of any material or manufacturing method, as long as they have good water permeability. However, the material of the wearer-side water-permeable sheet 2 and the outer water-permeable sheet 3 is preferably a chemical fiber that does not retain water, such as polyethylene, polypropylene, or polyethylene terephthalate. The wearer-side water-permeable sheet 2 and the outer water-permeable sheet 3 can be formed from a non-woven fabric made of 100% chemical fiber with low water retention, such as a spunbond non-woven fabric, a thermally bonded non-woven fabric, or an air-through non-woven fabric. To improve water permeability, the non-woven fabric is preferably hydrophilized. The outer water-permeable sheet 3 preferably has higher toughness than the wearer-side water-permeable sheet 2. The wearer-side water-permeable sheet 2 does not need to have such high toughness because it is supported by other nonwoven fabrics and maintains a good skin feel.

[0029] In this embodiment, the water guide sheet 4 is disposed between the wearer-side water-permeable sheet 2 and the outer water-permeable sheet 3, overlapping one side (the wearer's side) of the sensor unit 10. The water guide sheet 4 may also be disposed overlapping both sides of the sensor unit 10. In other words, the water guide sheet 4 may be disposed overlapping one side or both sides of the sensor unit 10. By limiting the arrangement to one side (the upper surface) as in this embodiment, manufacturing costs can be reduced.

[0030] The water-guiding sheet 4 has a generally rectangular planar shape and is sized to fit within the plane of the wearer-side water-permeable sheet 2 and the outer water-permeable sheet 3 when viewed from above. In other words, the water-guiding sheet 4 is disposed so as to be contained within the wearer-side water-permeable sheet 2 and the outer water-permeable sheet 3 when viewed from above. Specifically, the planar size of the water-guiding sheet 4 is smaller than that of the wearer-side water-permeable sheet 2 and the outer water-permeable sheet 3 by the size of the peripheral edge where the wearer-side water-permeable sheet 2 and the outer water-permeable sheet 3 are connected. Therefore, when the sensor sheet 1 is attached to the urine-collecting pad 50, the water-collecting sheet 4 extends from the abdomen portion 51 of the urine-collecting pad 50 via the connecting portion 53 to the back portion 52. Specifically, as described above, the water-collecting sheet 4 is configured to extend from the wearer's abdomen via the crotch portion to the back portion when the absorbent article is worn. Preferably, the water-collecting sheet 4 is configured to extend from a specific portion of the wearer's abdomen via the crotch portion to a specific portion of the back portion when the absorbent article is worn. In other words, the water guide sheet 4 extends along the longitudinal direction of the sensor sheet 1, and one end side, the center, and the other end side of the water guide sheet 4 in the longitudinal direction are respectively arranged to correspond to the wearer's abdomen, crotch, and back when the wearer wears the absorbent article.

[0031] The water-guiding sheet 4 is not limited in its manufacturing method or materials, as long as it is formed to guide a portion of the liquid that has passed through the wearer-side water-permeable sheet 2 toward the front (abdomen-side) where the sensor unit 10 is located. The water-guiding sheet 4 is formed, for example, from a nonwoven fabric with high water retention, such as cotton, pulp, rayon, or cuprammonium. The water-guiding sheet 4 is preferably manufactured using a method such as hydroentangling or needle punching, with the fibers oriented in the water-guiding direction (the direction forward of the sensor unit 10). This ensures that liquid discharged into the crotch region of the sensor sheet 1 is reliably guided to the sensor unit 10, which is located away from the crotch region.

[0032] The sensor portion 10 is formed in a sheet shape, and has a substantially rectangular planar shape that is short in the longitudinal direction of the sensor sheet 1 and long in the width direction of the sensor sheet 1 . The sensor unit 10 is provided on the side of the region of the water guiding sheet 4 corresponding to the wearer's abdomen side rather than the region of the water guiding sheet 4 corresponding to the wearer's crotch portion. Specifically, the sensor portion 10 is overlapped and positioned near the front end (abdomen-side end) in the longitudinal direction of the outer water-permeable sheet 3, and on the wearer-side surface of the outer water-permeable sheet 3, using an adhesive or pressure-sensitive adhesive. In other words, the sensor portion 10 is positioned in a region closer to the abdomen-side end than the crotch region corresponding to the wearer's crotch, in the longitudinal direction of the water-guiding sheet 4, when viewed from above. Alternatively, the sensor unit 10 may be provided closer to the area of ​​the water guide sheet 4 corresponding to the wearer's back than to the area of ​​the water guide sheet 4 corresponding to the wearer's crotch (specifically, closer to the back-side end). In other words, the sensor portion 10 may be positioned in an area closer to one end (abdomen) or the other end (back) of the water guide sheet 4 in the longitudinal direction than to the center of the water guide sheet 4 in the longitudinal direction corresponding to the wearer's crotch. By positioning the sensor portion 10 away from the area corresponding to the wearer's crotch, the wearer's discomfort caused by the sensor portion 10 can be reduced, thereby alleviating discomfort when wearing the sensor sheet 1. Note that the detailed structure of the sensor unit 10 itself will be described later.

[0033] A water-absorbent expandable member 6 is provided in a specific region of the wearer-side surface of the sensor portion 10 (this region includes at least the region where the missing portions 14a and 14b, described below, are provided). The water-absorbent expandable member 6 is configured to expand by absorbing water, thereby pressing the specific region of the sensor portion 10 in the direction normal to the surface. The function of this water-absorbent expandable member 6 will be described later. The water-absorbing and expanding material 6 is not limited in its manufacturing method or material as long as it is formed to expand by absorbing water. For example, the water-absorbing and expanding material 6 is formed of compressed cellulose sponge, water-absorbing polymer, or the like.

[0034] A water-absorbing sheet 5 is provided between the water-absorbing expandable member 6 and the water guide sheet 4 . The water-absorbent sheet 5 has substantially the same shape and size as the sensor portion 10 , and is arranged so as to overlap with the sensor portion 10 in a plan view. The water-absorbing sheet 5 absorbs and retains the liquid guided by the water-guiding sheet 4. The liquid seeping out of the water-absorbing sheet 5 reaches the water-absorbing expansion member 6 and the sensor portion 10. The absorbent sheet 5 can be formed to absorb and retain a certain amount of liquid, and its manufacturing method and raw materials are not limited. For example, the absorbent sheet 5 is formed of a nonwoven fabric containing super absorbent resin (SAP) fibers or a SAP-mixed nonwoven fabric.

[0035] Due to the laminated structure of the sensor sheet 1, most of the liquid discharged from the wearer in the crotch region of the wearer-side water-permeable sheet 2 sequentially passes through the wearer-side water-permeable sheet 2, the water-guiding sheet 4, and the outer water-permeable sheet 3, and is absorbed by the absorbent body 55 of the urine removal pad 50. Meanwhile, a portion of the liquid is guided forward (toward the abdomen) by the water-guiding sheet 4, absorbed and retained by the absorbent sheet 5. Furthermore, the liquid seeping out of the absorbent sheet 5 causes the water-absorbing expandable member 6 to expand, and also reaches the sensor portion 10. Therefore, according to the sensor sheet 1 , liquid discharged from the wearer can reliably reach the sensor portion 10 at a position away from the crotch region.

[0036] In addition, a shift prevention sheet 7 is provided on the surface of the outer water-permeable sheet 3 opposite to the wearer's side (outer side). The shift prevention sheet 7 suppresses positional shifting of the sensor sheet 1 relative to the urine-collecting pad 50. The shift prevention sheet 7 suppresses positional shifting of the sensor sheet 1 by indirectly overlapping the sensor sheet 1 with the absorbent article via the shift prevention sheet 7, compared to a case where the sensor sheet 1 is directly overlapped with the absorbent article, making it difficult for the sensor sheet 1 to move along the surface of the absorbent article. Therefore, in this embodiment, one surface (the wearer's side) of the shift prevention sheet 7 is bonded to the outer surface of the outer water-permeable sheet 3 via an adhesive or cohesive, and the other surface (the outer surface) has an adhesive layer or bonding layer (not shown) that secures it to the urine-collecting pad 50 via this adhesive layer or bonding layer. Furthermore, in cases where the sensor sheet 1 and the urine-collecting pad 50 are formed separately, a release sheet that can be peeled off from the adhesive layer or bonding layer is provided on the outer surface of the shift prevention sheet 7. In this case, to ensure ease of peeling, a release layer made of a resin such as polyethylene or silicone laminated between the release sheet and the adhesive layer or bonding layer may also be provided. Instead of this embodiment, a plurality of minute protrusions may be provided on the surface of the displacement preventing sheet 7 , and the protrusions may be engaged with the sensor sheet 1 and the surface of the absorbent article to suppress positional displacement of the sensor sheet 1 . In addition, the wearer-side water-permeable sheet 2 and the outer water-permeable sheet 3 may be referred to as a first water-permeable sheet and a second water-permeable sheet, respectively.

[0037] In this embodiment, the anti-drift sheet 7 has approximately the same shape and size as the sensor unit 10 and is positioned so as to overlap at least a portion of the sensor unit 10 when viewed from above. More specifically, the anti-drift sheet 7 is positioned so that the center of the anti-drift sheet 7 and the center of the sensor unit 10 coincide with each other when viewed from above, and the entire anti-drift sheet 7 overlaps the sensor unit 10. Thus, the anti-drift sheet 7 is preferably positioned so as to be contained within the surface of the sensor unit 10 when viewed from above. In other words, it is appropriate for the anti-drift sheet 7 to be positioned so as to be included within the sensor unit 10 when viewed from above. As a key function of absorbent articles, it is crucial to reliably absorb liquids such as urine and prevent them from returning to the wearer. Therefore, the sensor sheet 1, worn with an absorbent article, must be constructed to minimize the impairment of this function. Furthermore, the sensor sheet 1 includes a sensor portion 10 and a displacement prevention sheet 7 as components that block liquid from passing through the urine pad 50. Therefore, by arranging the displacement prevention sheet 7 so as to be housed within the surface of the sensor portion 10 in a plan view, the area of ​​the component that blocks liquid penetration can be minimized, thereby minimizing damage to the important functions of the absorbent article. However, in order to achieve the above-mentioned effects, although the effects will be slightly reduced, the area of ​​which the deviation preventing sheet 7 is a part may be arranged not to overlap with the sensor unit 10 in a plan view. In this case, it is appropriate to arrange that the area of ​​the deviation preventing sheet 7 that overlaps with the sensor unit 10 occupies more than half of the entire area of ​​the deviation preventing sheet 7.

[0038] <Sensor Unit 10> Figure 3 is a partial cross-sectional view of the sensor unit 10, Figure 4 This is a plan view of the sensor unit 10 when viewed from the wearer's side. Figure 5 The base material 100 of the sensor section 10 as viewed from the wearer's side, and the antenna section 11 , the lead section 13 , and the communication section 15 provided on the wearer-side surface of the base material 100 are selectively shown. Figure 6 The base material 103 in the sensor section 10 when viewed from the wearer's side and the lead wire section 13 provided on the surface of the base material 103 opposite to the wearer's side are selectively shown. Figure 3 Expressed Figure 4 The cross section along line BB in region A (region surrounded by a two-dot chain line frame) is shown.

[0039] The sensor portion 10 of this embodiment is configured so that the lead portion 13 becomes disconnected depending on the water absorption state of the water-absorbent sheet 5 or the water-swellable material 6. If the lead portion 13 becomes disconnected, the detection device cannot normally communicate wirelessly with the sensor portion 10, or the characteristics of the wireless communication with the sensor portion 10 change, so the detection device can detect that the absorbent article is wet. In this embodiment, the detection device can perform wetness detection by breaking or damaging the lead portion 13 , but the component that can be disconnected may be part of the antenna portion 11 or both the antenna portion 11 and the lead portion 13 . Furthermore, the detection device can detect wetness if the wireless communication state or wireless communication characteristics between the detection device and the sensor unit 10 change. Therefore, the disconnection state of the antenna unit 11 or the lead unit 13 is not limited to breakage or damage, but can also be achieved through dissolution or embrittlement.

[0040] The following descriptions of the positional relationships among the components of the sensor unit 10 use the X and Y directions shown in the various figures. The X and Y directions in the figures are parallel to the plane of the sensor unit 10 (horizontal directions). The Y direction is the longitudinal direction of the sensor sheet 1, and the X direction is the width direction of the sensor sheet 1. In the X direction, the direction toward +X is described as the +X direction or the +X side, and the direction toward −X is described as the −X direction or the −X side. In the Y direction, the direction toward +Y is described as the +Y direction or the +Y side, and the direction toward −Y is described as the −Y direction or the −Y side. The thickness direction of the sensor sheet 1 is sometimes referred to as the up-down direction. The upper surface side of the sensor sheet 1 is the wearer side, and the lower surface side is the urine absorbing pad 50 side.

[0041] The sensor unit 10 includes an antenna unit 11, a wire unit 13, and a communication unit 15. Figure 5 and Figure 6 As shown, the antenna portion 11 , the lead portion 13 , and the communication portion 15 are formed by overlapping a base material 100 and a base material 103 . The antenna unit 11 is connected to the communication unit 15 via the lead wire 13 . That is, the lead wire 13 connects the antenna unit 11 and the communication unit 15 .

[0042] The antenna unit 11 consists of an antenna unit 11a and an antenna unit 11b. The two antenna units 11a and 11b are symmetrically arranged on either side of the sensor unit 10 in the X direction, sandwiching the conductor unit 13 and the communication unit 15. Antenna unit 11a is positioned on the -X side relative to conductor unit 13 and the communication unit 15, while antenna unit 11b is positioned on the +X side relative to conductor unit 13 and the communication unit 15. Hereinafter, antenna unit 11a and antenna unit 11b will be collectively referred to as antenna unit 11, unless otherwise specified.

[0043] The antenna unit 11 performs wireless communication with a detection device as an external device. The radio waves output from the detection device are received by the antenna unit 11, and a signal corresponding to the radio waves is transmitted to the communication unit 15 via the lead unit 13. The communication unit 15 receives the signal received by the antenna unit 11 via the wire unit 13, and transmits the signal to the detection device via the antenna unit 11. In this embodiment, the communication unit 15 is an IC chip for an RFID tag, and is a passive IC chip that operates using power generated from the detection device through the antenna unit 11. In this embodiment, the antenna portion 11 or the lead portion 13 is disconnected depending on the water absorption state of the absorbent sheet 5 or the water-swellable material 6. Therefore, as described above, the signal (radio wave) transmitted from the communication portion 15 via the antenna portion 11 to the detection device can be used as a signal (radio wave) corresponding to the water absorption state of the absorbent sheet 5 or the water-swellable material 6, that is, the wetting condition of the absorbent article. In other words, the sensor portion 10 of the present invention is configured to output (transmit) radio waves corresponding to the wetting condition of the absorbent article to the outside via wireless communication.

[0044] The antenna portion 11 includes wide portions 111a and 111b, and serrated portions 112a and 112b. Wide portions 111a and 111b are formed into a generally rectangular shape that is elongated in the Y direction when viewed from above. Serrated portions 112a and 112b are narrower than wide portions 111a and 111b, forming a serrated shape in the Y direction and extending in the X direction. One end of serrated portions 112a and 112b is connected to wide portion 111a and 111b, respectively, and the other end is connected to the lead portion 13.

[0045] The lead portion 13 is a wiring connecting the antenna portion 11 and the communication portion 15 , and is formed by connecting a wiring provided on a surface of the substrate 100 facing the substrate 103 and a wiring provided on a surface of the substrate 103 facing the substrate 100 . First, use Figure 5 The structure of the lead portion 13 provided on the substrate 100 will be described. The conductor portion 13 includes a linear pattern forming portion 131a, a linear pattern forming portion 132a, a linear pattern forming portion 132b, and a linear pattern forming portion 131b. The linear pattern forming portion 131a is connected to one end of the serrated portion 112a and extends in the X direction. The linear pattern forming portion 132a is arranged on an extension of the linear pattern forming portion 131a, sandwiching the missing portion 14a therebetween, and extends in the X direction. The linear pattern forming portion 132b is connected to the linear pattern forming portion 132a and extends in the X direction. The linear pattern forming portion 131b is arranged on an extension of the linear pattern forming portion 132b, sandwiching the missing portion 14b therebetween, and extends in the X direction.

[0046] The lead portion 13 also includes a connecting portion 133 and looped pattern forming portions 134a, 135a, 136a, 137a, 138a, 134b, 135b, 136b, 137b, and 138b. One end of the connecting portion 133 is connected to the boundary between the linear pattern forming portion 132a and the linear pattern forming portion 132b, and the connecting portion 133 extends from the boundary in the Y direction. The annular pattern forming portion 134a is connected to the other end of the connecting portion 133 and extends in the X direction from the other end of the connecting portion 133. The annular pattern forming portion 135a is arranged on an extension line of the annular pattern forming portion 134a so as to sandwich the missing portion 14a and extend in the X direction. One end of the annular pattern forming portion 136a is connected to one end of the annular pattern forming portion 135a and extends in the Y direction from the other end of the annular pattern forming portion 135a. The annular pattern forming portion 137a is connected to the other end of the annular pattern forming portion 136a and extends in the X direction from the other end of the annular pattern forming portion 136a. The annular pattern forming portion 138a is arranged on an extension line of the annular pattern forming portion 137a so as to sandwich the missing portion 14a and extend in the X direction.

[0047] The annular pattern forming portion 134b is connected to the other end of the connecting portion 133 and extends in the X direction from the other end of the connecting portion 133. The annular pattern forming portion 135b is arranged on an extension line of the annular pattern forming portion 134b so as to sandwich the missing portion 14b and extend in the X direction. One end of the annular pattern forming portion 136b is connected to one end of the annular pattern forming portion 135b, and the annular pattern forming portion 136b extends from the one end of the annular pattern forming portion 135b in the Y direction. The annular pattern forming portion 137b is connected to the other end of the annular pattern forming portion 136b and extends in the X direction from the other end of the annular pattern forming portion 136b. The annular pattern forming portion 138b is arranged on an extension line of the annular pattern forming portion 137b so as to sandwich the missing portion 14b and extend in the X direction. The ring pattern forming portion 138 a and the ring pattern forming portion 138 b are connected to the communication portion 15 , and are arranged on an extension line to each other via the communication portion 15 .

[0048] Next, use Figure 4 and Figure 6 The structure of the lead portion 13 provided on the substrate 103 will be described. like Figure 6 As shown, the lead portion 13 includes bridge portions 171 a , 171 b , 172 a , 172 b , 173 a , and 173 b , which are provided on the substrate 103 and extend in the X direction, respectively. Furthermore, the substrate 100 and the substrate 103 are overlapped to form Figure 4 The wiring of the conductor portion 13 is shown. Specifically, bridge portion 171a connects linear pattern forming portion 131a and linear pattern forming portion 132a. Bridge portion 171b connects linear pattern forming portion 132b and linear pattern forming portion 131b. Thus, a linear wiring pattern of conductor portion 13 extending linearly in the X direction is formed by linear pattern forming portion 131a, bridge portion 171a, linear pattern forming portion 132a, linear pattern forming portion 132b, bridge portion 171b, and linear pattern forming portion 131b. The bridge portion 172a connects the annular pattern forming portion 135a to the annular pattern forming portion 134a. The bridge portion 172b connects the annular pattern forming portion 134b to the annular pattern forming portion 135b. The bridge portion 173a connects the annular pattern forming portion 137a to the annular pattern forming portion 138a. The bridge portion 173b connects the annular pattern forming portion 138b to the annular pattern forming portion 137b. Thus, the annular wiring pattern of conductor portion 13 is formed by annular pattern forming portion 138a, bridge portion 173a, annular pattern forming portion 137a, annular pattern forming portion 136a, annular pattern forming portion 135a, bridge portion 172a, annular pattern forming portion 134a, annular pattern forming portion 134b, bridge portion 172b, annular pattern forming portion 135b, annular pattern forming portion 136b, annular pattern forming portion 137b, bridge portion 173b, and annular pattern forming portion 138b. The annular wiring pattern is formed into a generally rectangular ring shape when viewed from above. However, since communication portion 15 is connected between annular pattern forming portion 138a and annular pattern forming portion 138b, the annular wiring pattern becomes discontinuous at the location of communication portion 15. Connecting portion 133 connects the linear wiring pattern of conductor portion 13 to the annular wiring pattern.

[0049] Here, the bridge portion 171a, the bridge portion 172a, and the bridge portion 173a are respectively arranged to straddle the missing portion 14a, and the bridge portion 171b, the bridge portion 172b, and the bridge portion 173b are respectively arranged to straddle the missing portion 14b. The bridge portion 173a is provided between the annular pattern forming portion 137a and the annular pattern forming portion 138a, electrically connecting the annular pattern forming portion 137a and the annular pattern forming portion 138a. Similarly, the bridge portion 173b is provided between the annular pattern forming portion 138b and the annular pattern forming portion 137b, electrically connecting the annular pattern forming portion 138b and the annular pattern forming portion 137b. Similarly, the bridge portion 171a is provided between the linear pattern forming portion 131a and the linear pattern forming portion 132a, electrically connecting the linear pattern forming portions 131a and 132a to each other. The bridge portion 171b is provided between the linear pattern forming portion 132b and the linear pattern forming portion 131b, electrically connecting the linear pattern forming portions 132b and 131b to each other. The bridge portion 172a is provided between the annular pattern forming portion 135a and the annular pattern forming portion 134a, electrically connecting the annular pattern forming portions 135a and 134a to each other. The bridge portion 172b is provided between the annular pattern forming portion 134b and the annular pattern forming portion 135b, electrically connecting the annular pattern forming portions 134b and 135b to each other.

[0050] In this manner, the sensor portion 10 of the present embodiment is formed by overlapping the substrate 100 and the substrate 103 . The substrate 100 is formed to be insoluble in liquid. The substrate 100 can be made of, for example, paper or a resin film. The resin material constituting the resin film is not particularly limited, and examples thereof include polyethylene, polystyrene, polypropylene, and polyester. However, the substrate 100 may also be formed to be soluble in liquid. The thickness of the substrate 100 is not particularly limited, but is preferably 10 μm or greater and 75 μm or less, for example. By setting the thickness of the substrate 100 to 10 μm or greater, the substrate 100 can stably support the wiring pattern, such as the antenna portion 11, and achieve sufficient structural strength. Furthermore, by setting the thickness of the substrate 100 to 75 μm or less, the substrate 100 can be made highly flexible.

[0051] The substrate 103 is formed to be soluble in liquid. Therefore, if a slight external force is applied to the wiring pattern of the lead portion 13 provided on the substrate 103 while the substrate 103 is dissolved by sufficient contact with the liquid, the wiring pattern can be easily broken or cracked, thereby disconnecting the sensor portion 10. This allows the sensor portion 10 to more reliably detect the presence of liquid. Here, the substrate 103 being soluble in liquid means that the substrate 103 dissolves (melts) upon contact with the liquid. More specifically, for example, if the liquid contains water, the substrate 103 being soluble in liquid means that the substrate 103 dissolves upon contact with water (liquid).

[0052] The substrate 103 is, for example, made of PVA (polyvinyl alcohol). By making the substrate 103 comprise PVA, it is possible to achieve a structure in which the substrate 103 dissolves well when in contact with liquid. However, if the substrate 103 is water-soluble, the material of the substrate 103 is not limited to PVA; for example, polyvinyl pyrrolidone, water-soluble polyester, water-soluble paper material, or sheet material containing starch as a source may also be used. The thickness of substrate 103 is not particularly limited, but is preferably 5 μm or more and 100 μm or less, for example. By setting the thickness of substrate 103 to 5 μm or more, substrate 103 can stably support the wiring pattern of lead portion 13 before contact with liquid. By setting the thickness of substrate 103 to 100 μm or less, substrate 103 can dissolve rapidly upon contact with liquid.

[0053] Next, use Figure 3 A portion of the sensor unit 10 ( Figure 4 The stacked structure of the illustrated region A) will be described in more detail. In region A of the sensor section 10, annular pattern forming sections 137a, 138a, 137b, and 138b are formed on the wearer-side surface (upper surface) of the substrate 100. A communication section 15 is provided between the annular pattern forming sections 138a and 138b, electrically connected to the annular pattern forming sections 138a and 138b. The connection method between the communication section 15 and the annular pattern forming sections 138a and 138b is not limited in any way; for example, one mounting terminal of the communication section 15 may be electrically connected to one end of the annular pattern forming section 138a, while the other mounting terminal of the communication section 15 may be electrically connected to one end of the annular pattern forming section 138b.

[0054] In addition, in the region A of the sensor section 10 , the substrate 100 is provided with a notched portion 14 a and a notched portion 14 b . The missing portions 14a and 14b are openings formed in the substrate 100. That is, the missing portions 14a and 14b penetrate the front and back surfaces of the substrate 100 in the thickness direction (vertical direction) of the substrate 100. Therefore, the wiring pattern of the conductive portion 13 is not formed in the areas of the substrate 100 where the missing portions 14a and 14b exist. Alternatively, the missing portions 14a and 14b may be in the form of slits.

[0055] Meanwhile, in region A of the sensor section 10, bridge portions 173a and 173b are formed on the surface of the substrate 103 that faces the substrate 100. More specifically, bridge portions 173a and 173b are formed in the regions of this surface of the substrate 103 that overlap with the missing portions 14a and 14b. Furthermore, bridge portion 173a spans between annular pattern forming portions 137a and 138a, electrically connecting the two. Bridge portion 173b spans between annular pattern forming portions 138b and 137b, electrically connecting the two.

[0056] In addition, in this embodiment, a bridge portion 173a and a bridge portion 173b are formed on the surface of the substrate 103 opposite the substrate 100, with a soluble layer 104, which is a liquid-soluble adhesive layer, interposed therebetween. The adhesive forming such a water-soluble (or aqueous) soluble layer 104 is not particularly limited, and examples thereof include starch paste, acacia gum, and aqueous acrylic emulsions. Aqueous acrylic emulsions can be prepared, for example, by copolymerizing a carboxyl group-containing acrylic monomer and adding an alcohol or polyethylene oxide. Alternatively, the soluble layer 104 may be constructed to include two or more water-soluble (or aqueous) adhesives. The soluble layer 104 not only adheres the substrate 103 to the bridge portions 173a and 173b, but also adheres the substrate 103 to the substrate 100 and the annular pattern forming portions 137a, 138a, 137b, and 138b. However, a part of the sensor unit 10 ( Figure 4 The stacked structure of the region A) shown is not limited to Figure 3 For example, an adhesive layer and a soluble layer may be provided in the region of bridge portions 173a and 173b that overlaps with missing portions 14a and 14b. In this case, the adhesive layer covers missing portions 14a and 14b, the soluble layer is laminated on the adhesive layer, and then bridge portions 173a and 173b are laminated. Furthermore, in the region where the adhesive layer and soluble layer are not provided, bridge portion 173a electrically connects annular pattern forming portion 137a and annular pattern forming portion 138a, and bridge portion 173b electrically connects annular pattern forming portion 138b and annular pattern forming portion 137b.

[0057] With this structure, the sensor portion 10 comes into contact with liquid that has seeped out, guided by the water-guiding sheet 4 and absorbed by the water-absorbent sheet 5, causing the lead portion 13 of the sensor portion 10 to become disconnected. Specifically, the liquid that has seeped out of the water-absorbent sheet 5 comes into contact with the substrate 103, dissolving it. The water-swellable material 6, having absorbed this liquid, expands, applying a pressing force in the direction normal to the surface of the substrate 103 toward the missing portions 14a and 14b. This pressing force causes one or more of the bridge portions 171a, 172a, 173a, 171b, 172b, and 173b to break or crack, causing the lead portion 13 to become disconnected.

[0058] In this embodiment, the wiring patterns of antenna 11 and conductor 13 are formed to be insoluble in liquid. However, the methods and materials used to form the wiring patterns of antenna 11 and conductor 13 are not limited to this example. The wiring patterns of antenna 11 and conductor 13 may also be formed to be soluble in liquid or to become brittle when soaked in liquid. The configuration in which the antenna portion 11 or the lead portion 13 is disconnected is not limited to this embodiment.

[0059] Furthermore, as described above, the sensor sheet 1 of this embodiment includes the absorbent sheet 5 and the water-swelling material 6 as water-absorbing components, making it possible to adjust the timing of the sensor portion 10 entering the disconnection state based on their water absorption capacity. For example, when using an absorbent sheet 5 and water-swelling material 6 with a high water absorption capacity, the amount of liquid required to disconnect the sensor portion 10 is greater than when using an absorbent sheet 5 and water-swelling material 6 with a low water absorption capacity. In other words, when using an absorbent sheet 5 and water-swelling material 6 with a high water absorption capacity, the timing of the detection device detecting wetting can be delayed until the absorbent article becomes more wet. For example, a plurality of sensor sheets 1 are provided in a manner that includes absorbent components (absorbent sheet 5 and absorbent expansion member 6) having different amounts of water absorption that can cause the sensor portion 10 to be disconnected, thereby enabling selection of an appropriate sensor sheet 1 corresponding to the preferences of a user such as a caregiver or the wearer's excretion status. Such a plurality of sensor sheets 1 can be referred to as a wetness detection sensor sheet set. The wetness detection sensor sheet set may be sold as a set, or may be sold individually by selecting all or part of the plurality of sensor sheets.

[0060] [Wetting Detection System] Next, a description will be given of a wetting detection system for detecting wetting of an absorbent article having the sensor sheet 1 . Figure 7 This is a diagram conceptually showing the hardware configuration of a wetness detection system (hereinafter sometimes referred to as a “system”). The wetness detection system of this embodiment is composed of an RFID reader / writer 60 , a user terminal 70 , a server device 90 , and the like. The user terminal 70 is a terminal (computer) mainly used by a caregiver, such as Figure 7 As shown, for example, the user terminal 70 includes a CPU (central processing unit) 71, a memory 72, a display unit 73, a touch sensor 74, a communication unit 75, etc., which are interconnected by a bus. The user terminal 70 can be any general-purpose computer, and there is no limitation on the hardware elements constituting the user terminal 70. The user terminal 70 may also include a camera unit, a microphone unit, a speaker unit, etc. Figure 7 Other hardware elements not shown in the figure. The user terminal 70 is preferably a portable terminal such as a smartphone or a tablet computer so as to be easy to carry.

[0061] The CPU 71 includes both hardware and software components and controls the overall operation of the system. The CPU 71 is connected to the other units via a bus or other communication lines. In addition to a conventional CPU, the CPU 71 may also be composed of an application-specific integrated circuit (ASIC), a DSP (digital signal processor), a GPU (graphics processing unit), or the like. The memory 72 is a RAM (Random Access Memory), a ROM (Read Only Memory), or an auxiliary storage device (a hard disk or the like). The display unit 73 includes a monitor such as an LCD (Liquid Crystal Display) or a CRT (Cathode Ray Tube) display, and performs display processing. The touch sensor 74 receives user input by sensing external contact. The touch sensor 74 can also be a sensor capable of detecting a user's finger or other external contact even in a non-contact state. Furthermore, the display unit 73 and the touch sensor 74 can also be implemented as a touch panel unit. Furthermore, the user terminal 70 can also include an input / output interface (not shown) connected to an input device such as a mouse or keyboard, in addition to or in place of the touch sensor 74. The communication unit 75 performs wireless communication with other terminals such as the RFID reader / writer 60 and the server device 90 via a communication network. Examples of the communication network include a mobile phone network, a Wi-Fi (Wireless Fidelity) network, an Internet communication network, a dedicated line network, and a LAN (Local Area Network). In this embodiment, the communication method of the communication unit 75 is not limited. The user terminal 70 is configured to be able to perform wireless communication with the RFID reader / writer 60 and the server device 90 via the communication unit 75 .

[0062] The server device 90 is a so-called computer, and includes, for example, a CPU, memory, and input / output interfaces (I / Fs) interconnected by a bus. These hardware elements constituting the server device 90 are the same as those of the user terminal 70, and the hardware structure of the server device 90 is not limited in any way.

[0063] The RFID reader / writer 60 is a device capable of wirelessly communicating with the sensor unit 10 of the sensor sheet 1. The RFID reader / writer 60 includes an antenna. The antenna outputs radio waves in a predetermined frequency band (such as the UHF band and microwave band) used by RFID tags (hereinafter sometimes referred to as "RFID tag radio waves"). The antenna also receives radio waves output from the sensor unit 10 of the sensor sheet 1 in response to these radio waves, and performs demodulation and decoding on the received radio waves. In this embodiment, the sensor unit 10 uses radio waves in the UHF band. The user terminal 70 can obtain the sensor ID stored in the communication unit 15 of the sensor unit 10 obtained by demodulation, etc., by wirelessly communicating with the RFID reader / writer 60. The connection form and communication method between the RFID reader / writer 60 and the user terminal 70 are not limited in any way. In addition, although the hardware structure of the RFID reader / writer 60 is not shown in the figure, it is sufficient as long as it has the same hardware structure as that of an existing RFID reader / writer.

[0064] As described above, in this embodiment, the communication unit 15 of the sensor sheet 1 is a passive RFID tag IC chip. The sensor ID stored in the communication unit 15 of the sensor sheet 1 is an ID unique to each sensor sheet 1. However, the sensor ID stored in the communication unit 15 only needs to be a unique identifier for each RFID tag IC chip. In the following description, it may be described that the sensor ID is stored in the sensor sheet 1 or the sensor unit 10 .

[0065] Figure 8 This is a diagram conceptually showing the software structure of the wetness detection system. Although Figure 8Although the software structure of the RFID reader / writer 60 is not shown in the figure, the RFID reader / writer 60 only needs to have the general software structure of an RFID tag reader / writer. Specifically, the RFID reader / writer 60 outputs radio waves for RFID tags, receives radio waves output from the sensor unit 10 of the sensor sheet 1 in response to these output radio waves, and demodulates and decodes the received radio waves to obtain the sensor ID stored in the communication unit 15 of the sensor sheet 1. The RFID reader / writer 60 can output radio waves in response to an instruction signal from the user terminal 70, in response to user operation of operation buttons provided on the RFID reader / writer 60, or periodically without triggering.

[0066] If the sensor ID can be obtained normally, the RFID reader / writer 60 sends the sensor ID to the user terminal 70. On the other hand, if the sensor ID cannot be obtained even after repeating the radio wave output a predetermined number of times, the RFID reader / writer 60 sends information indicating no response (hereinafter referred to as no response information) to the user terminal 70. However, if the sensor ID cannot be obtained, the RFID reader / writer 60 may not send anything. In addition, regardless of whether the acquisition of the sensor ID is successful, the RFID reader / writer 60 may determine that there is no response and generate no response information when the radio wave intensity output from the sensor unit 10 and received by the RFID reader / writer 60 is lower than a predetermined threshold. That is, the RFID reader / writer 60 may determine that there is no response and generate no response information when there is no predetermined response from the sensor unit 10 to the output from the RFID reader / writer 60 (for example, when the sensor ID cannot be obtained, or when the received radio wave intensity is lower than a predetermined threshold).

[0067] The server device 90 includes at least a wearer management database 91 (hereinafter sometimes referred to as wearer management DB91 ) as a software element. The wearer management DB 91 is a database that manages information of care receivers who are targets of wetting detection. The target care receivers wear absorbent articles (such as the urine absorbing pad 50 in the above example) including the sensor sheet 1 and are also recorded as wearers.

[0068] Figure 9 2 is a diagram showing an example of a wearer information table stored in the wearer management database 91 . like Figure 9 As shown, the wearer information table stores records for each wearer (care recipient), and each record stores information items such as wearer ID, sensor ID, wearing time, sensor position, etc. Hereinafter, these information items included in the wearer information table may also be described as fields. The wearer ID field stores the wearer ID, which is identification information of the wearer (care receiver). In this system, a unique wearer ID is assigned to each wearer.

[0069] The sensor ID field stores the sensor ID of the sensor sheet 1 of the absorbent article worn by the target wearer. Therefore, if a wearer's absorbent article is replaced, the data in the sensor ID field of the wearer's record containing the wearer ID is updated to the sensor ID of the replaced sensor sheet 1. The wearing time field stores date and time information on when the absorbent article corresponding to the sensor ID stored in the sensor ID field is worn, or date and time information on when the target wearer replaces the absorbent article.

[0070] The sensor position field stores information indicating the position of the sensor portion 10 of the sensor sheet 1 in the absorbent article worn by the target wearer. As described above, in the sensor sheet 1, the sensor portion 10 is not provided in the crotch of the wearer but in a region close to the end of the longitudinal direction of the sensor sheet 1. Figure 1 When the sensor sheet 1 is attached to an absorbent article (urine removal pad 50) as shown in the example, the sensor portion 10 is located on the wearer's abdomen. Figure 1 When the sensor sheet 1 is attached to an absorbent article in the opposite direction, the sensor portion 10 is located on the back side of the wearer. When the sensor sheet 1 is formed separately from the absorbent article and requires installation, the position of the sensor portion 10 of the sensor sheet 1 relative to the absorbent article is not necessarily fixed. This is also because the outer shape of the sensor sheet 1 is generally rectangular as described above. Therefore, the sensor position field stores information that can identify whether the sensor portion 10 is located on the abdomen side or on the back side as information indicating the position of the sensor portion 10 of the sensor sheet 1 in the absorbent article.

[0071] like Figure 8 As shown, the user terminal 70 includes a communication processing unit 81, a determination unit 82, an information management unit 83, and a display processing unit 84. These software elements (processing modules) are implemented, for example, by the CPU 71 executing a computer program stored in the memory 72. The computer program can also be installed from a portable recording medium such as a memory card or another computer on the network via the communication unit 75 and stored in the memory 72. In addition, part or all of the communication processing unit 81 , determination unit 82 , information management unit 83 , and display processing unit 84 may be configured as hardware elements integrally with the CPU 71 in the user terminal 70 , or may be configured independently of the CPU 71 .

[0072] The communication processing unit 81 wirelessly communicates with the RFID reader / writer 60 via the communication unit 75. The communication processing unit 81 can receive the sensor ID transmitted from the RFID reader / writer 60. When the RFID reader / writer 60 transmits no-response information, the communication processing unit 81 can also receive the no-response information. Alternatively, the communication processing unit 81 may transmit an instruction signal for outputting radio waves for RFID tags to the RFID reader / writer 60. In this case, the communication processing unit 81 may generate the no-response information when the sensor ID transmitted from the RFID reader / writer 60 cannot be received even after a predetermined time has passed since the instruction signal was transmitted to the RFID reader / writer 60. As described above, in this embodiment, the communication processing unit 81 of the user terminal 70 and the RFID reader / writer 60 correspond to a terminal communication unit (communication processing device) that wirelessly communicates with the sensor unit 10 of the sensor sheet 1. The terminal communication unit may also include a communication unit 75.

[0073] The determination unit 82 determines whether the absorbent article is wet based on the wireless communication status between the terminal communication unit and the sensor unit 10 of the sensor sheet 1. In this embodiment, the determination unit 82 receives the sensor ID or no-response information transmitted from the RFID reader / writer 60 via the communication processing unit 81, and identifies the wetness of the absorbent article based on the sensor ID or no-response information. The determination unit 82 functions as a determination device that determines whether the absorbent article is wet based on the wireless communication status between the communication processing unit and the sensor unit 10. When radio waves are output from the RFID reader / writer 60 to the sensor unit 10 and a predetermined response is received from the sensor unit 10 to the RFID reader / writer 60, the determination unit 82 determines that the absorbent article is not wet. When radio waves are output from the RFID reader / writer 60 to the sensor unit 10 and no predetermined response is received from the sensor unit 10 to the RFID reader / writer 60, the determination unit 82 determines that the absorbent article is wet. The case where there is a predetermined response is, for example, the case where the RFID reader / writer 60 receives the sensor ID transmitted from the sensor unit 10. The case where there is no predetermined response is, for example, the case where the RFID reader / writer 60 cannot receive the sensor ID or the case where the received radio wave intensity is lower than a predetermined threshold, and the case where the determination unit 82 receives a no-response message transmitted from the RFID reader / writer 60. The case where the determination unit 82 receives the no-response message indicates that the wireless communication state between the user terminal 70 and the sensor unit 10 is a specific wireless communication state corresponding to the disconnection state of the antenna unit 11 or the wire unit 13. In addition, in this embodiment, as described below, even when the determination unit 82 receives no-response information, the wetness determination is not performed based solely on the reception of the no-response information, but is performed after performing processing for suppressing erroneous determination. Figure 10 The example shown is an example of the operation of this system including such processing.

[0074] Specifically, the determination unit 82 maintains the wearer ID and sensor ID of the currently designated wearer, and when receiving the sensor ID sent from the RFID reader / writer 60, compares the received sensor ID with the currently designated sensor ID maintained. When the two sensor IDs are consistent, it is determined that the absorbent article is not wet. Furthermore, when the two sensor IDs do not match, it can be considered that wireless communication has been performed with the sensor unit 10 of an unexpected sensor sheet 1 , and therefore the determination unit 82 may instruct the display processing unit 84 to display an error.

[0075] In the sensor sheet 1, the sensor portion 10 may be located on the back side or the abdomen side relative to the absorbent article. Therefore, if the RFID reader / writer 60 is directed toward the back side or the abdomen side, which is different from the position of the sensor portion 10, there is a possibility that a no-response message will be transmitted from the RFID reader / writer 60 even though the absorbent article is not wet. The no-response message transmitted in this case will be referred to as position error no-response message. The determination unit 82 cannot determine whether the received no-response information is position error no-response information.

[0076] Therefore, when the determination unit 82 receives the no-response information, it notifies the display processing unit 84 of this fact. That is, the determination unit 82 does not determine that the absorbent article is wet when the no-response information is received, but instead notifies the display processing unit 84 that the no-response information has been received, i.e., that the wireless state is the specific wireless communication state. In response to the notification from the determination unit 82, the display processing unit 84 causes the display unit 73 to display an alarm indicating the relationship between the position of the RFID reader / writer 60 (particularly the antenna) relative to the absorbent article and the position of the sensor unit 10 relative to the absorbent article. Details of the alarm display will be described later. In this case, the determination unit 82 determines whether the absorbent article is wet based on the user's operation in response to the alarm display shown above. Specifically, if a specific operation is performed in response to the alarm display, the determination unit 82 determines that the absorbent article is wet. If an operation other than the specific operation is performed in response to the alarm display, the determination unit 82 may not perform a wetness determination and may instead wait for another sensor ID or a no-response message to be received. In this way, even when the determination unit 82 receives no response information, it does not immediately perform the wetness determination, but temporarily postpones the determination and displays an alert to the user to confirm the position of the RFID reader / writer 60, thereby suppressing erroneous detection of wetness. Here, “wetting determination” of the absorbent article means determining that the absorbent article including the sensor sheet 1 having the sensor ID is wet.

[0077] The information management unit 83 can access the wearer management DB 91 in the server device 90 by wireless communication via the communication unit 75. The wearer management DB 91 (server device 90) functions as an information storage unit of this system. When the care receiver wears the absorbent article including the sensor sheet 1 (including when the article is replaced), the information management unit 83 reflects the sensor ID, wearing date and time information, and sensor position information stored in the sensor sheet 1 to the wearer information table of the wearer management DB 91. Specifically, the information management unit 83 identifies the wearer ID of the target wearer (care receiver) when the absorbent article is worn (including when the article is replaced), obtains the sensor ID from the RFID reader / writer 60 via the communication processing unit 81, and sets the newly obtained sensor ID, the wearing date and time information, and the position information of the sensor unit 10 in the absorbent article (back side or abdomen side) in the sensor ID field, wearing time field, and sensor position field of the record containing the identified wearer ID stored in the wearer information table.

[0078] Thus, according to this system, for each wearer, not only the sensor ID and wearing time of the sensor sheet 1 worn are managed, but also the position information of the sensor unit 10 relative to the absorbent article is managed. Thus, by providing the position information of the sensor unit 10, it is possible to prevent errors in the position and direction of the RFID reader / writer 60, thereby preventing false detection of wetness of the absorbent article.

[0079] The display processing unit 84 controls the display unit 73 and performs various display processes. Specifically, the display processing unit 84 causes the display unit 73 to display the above-mentioned warning display. This warning display urges the user to pay attention to the relationship between the position of the RFID reader / writer 60 and the position of the sensor unit 10 relative to the absorbent article. For example, the warning display may display a message such as "The sensor may be attached to the opposite side of the back or abdomen. Do you want to reposition the reader / writer and read again?" The warning display also includes an "OK" button and a "Retry" button along with the message. If the "OK" button is pressed as a user operation in response to the alarm display (the specific operation described above), the determination unit 82 determines that the absorbent article is wet. If the "Retry" button is pressed, the determination unit 82 does not perform a wet determination of the absorbent article and waits for another sensor ID or a no-response message to be received. The display processing unit 84 causes the display unit 73 to display a notification display of the result of the wetting determination by the determination unit 82 .

[0080] In addition, when the care receiver wears the absorbent article with the sensor sheet 1 (including when replacing it) and when confirming whether the absorbent article is wet, the display processing unit 84 causes the display unit 73 to display a wearer designation display for identifying the wearer ID of the care receiver (wearer). The wearer designation display for example comprises a wearer list generated according to the wearer information table of the wearer management DB 91, and an operation of specifying a wearer from the list can be performed. In addition, an operation of retrieving a wearer from the wearer list can also be performed by inputting the name of the wearer. When a user operation is performed to designate a display for a wearer, the display processing unit 84 determines the wearer ID of the designated wearer and the sensor ID associated with the wearer ID, and stores these as the currently designated wearer ID and sensor ID in the determination unit 82. Furthermore, the display processing unit 84 notifies the information management unit 83 of the designated wearer ID as the target wearer ID.

[0081] The following uses Figure 10 and Figure 11 An operation example of the wetness detection system is described. Figure 10 This is a flowchart showing an example of the operation of the wetness detection system during wetness confirmation. Figure 11 This is a flowchart showing an example of the operation of the wetness detection system when the absorbent article is worn or replaced.

[0082] First, use Figure 10 The operation of the wetness detection system during wetness confirmation will be described. In the user terminal 70, the display processing unit 84 causes the display unit 73 to display a wearer designation display (S101). As described above, the wearer designation display includes a wearer list, and a user operation of designating a wearer from the wearer list is possible. When a designation operation for designating a wearer is performed for the wearer designation display ( S102 : YES), the display processing unit 84 identifies the wearer ID and sensor ID of the designated wearer from the wearer information table of the wearer management DB 91 and stores them in the determination unit 82 .

[0083] Next, the RFID reader / writer 60 transmits RFID tag radio waves from its antenna (S103). The RFID reader / writer 60 may transmit RFID tag radio waves by receiving an instruction signal from the user terminal 70, or by a user operating an operation button provided on the RFID reader / writer 60. Alternatively, the RFID reader / writer 60 may periodically transmit RFID tag radio waves without such a trigger.

[0084] When the sensor section 10 (communication section 15) of the sensor sheet 1 is not in contact with liquid and is operating normally, the RFID reader / writer 60 can receive the radio waves output from the sensor section 10 and obtain the sensor ID from the radio waves. On the other hand, if the antenna section 11 or the lead section 13 is disconnected due to contact with liquid, the RFID reader / writer 60 cannot obtain the sensor ID. If the RFID reader / writer 60 successfully receives the sensor ID, it transmits the sensor ID to the user terminal 70, and the communication processing unit 81 of the user terminal 70 receives the sensor ID (S104: Yes). On the other hand, if the RFID reader / writer 60 fails to receive the sensor ID, it retransmits the RFID tag radio wave (S103) until the number of retries exceeds the threshold (S105). If the RFID reader / writer 60 fails to receive the sensor ID until the number of retries exceeds the threshold (S104: No, S105: Yes), it transmits a no-response message to the user terminal 70, and the communication processing unit 81 receives the no-response message.

[0085] When the communication processing unit 81 receives the sensor ID, the determination unit 82 determines that the absorbent article of the designated wearer is not wet (S111). Then, the display processing unit 84 causes the display unit 73 to display a message notifying that the absorbent article is not wet (S112). Here, when the sensor ID is received, the determination unit 82 may compare the currently designated sensor ID stored therein with the received sensor ID (not shown). In this case, if the two sensor IDs match, the determination unit 82 may determine that the device is not wet (S111). If the two sensor IDs do not match, the determination is not made and the display unit 73 may display an error message by instructing the display processing unit 84. In this manner, when the sensor ID is acquired from the sensor portion 10 of an unexpected sensor sheet 1 different from the sensor sheet 1 attached to the absorbent article of the designated wearer, erroneous determination can be suppressed.

[0086] When the communication processing unit 81 receives the no-response information, the determination unit 82 notifies the display processing unit 84 of the information. In response, the display processing unit 84 causes the display unit 73 to display an alarm (S106). As described above, the alarm display is a display that urges the user to pay attention to the relationship between the position of the RFID reader 60 relative to the absorbent article and the position of the sensor part 10 relative to the absorbent article. For example, the alarm display includes a display of an "OK" operation button and a "Retry" operation button.

[0087] When the user presses the "OK" operation button (OK operation), the determination unit 82 performs a "wetting determination" of the absorbent article (S108), and the display processing unit 84 causes the display unit 73 to display a display notifying the designated wearer that the absorbent article is wet (S109). On the other hand, if the user presses the "retry" button (retry operation), the determination unit 82 does not perform the wetness determination and waits for the next reception of the sensor ID or the reception of the no-response message (S103). At this time, the determination unit 82 may also instruct the RFID reader / writer 60 to transmit the RFID tag radio wave through the communication processing unit 81.

[0088] Thus, according to this system, when the sensor ID cannot be obtained from the sensor unit 10, an alarm is displayed, such as urging the caregiver as the user to pay attention to whether the reading position of the RFID reader 60 is incorrect, thereby preventing the absorbent article from being mistakenly judged to be wet even though it is not wet.

[0089] Next, use Figure 11 The operation of this system when the absorbent article is worn or replaced will be described. Even in this case, in the user terminal 70, the display processing unit 84 causes the display unit 73 to display the wearer specifying display (S121). The wearer specifying display is as described above. If a designation operation for designating a wearer is performed for the wearer designation display ( S122 : YES), the display processing unit 84 identifies the wearer ID of the designated wearer from the wearer information table of the wearer management DB 91 and stores it in the information management unit 83 .

[0090] Next, the RFID reader / writer 60 transmits RFID tag radio waves from its antenna (S123). The RFID reader / writer 60 may transmit RFID tag radio waves by receiving an instruction signal from the user terminal 70, or by a user operating an operation button provided on the RFID reader / writer 60. Alternatively, the RFID reader / writer 60 may periodically transmit RFID tag radio waves without such a trigger.

[0091] In this case, the absorbent article including the sensor sheet 1 is in a new state before being worn, and the RFID reader / writer 60 can be brought sufficiently close to the sensor sheet 1. Therefore, the RFID reader / writer 60 can normally receive the radio waves output from the sensor unit 10 and obtain the sensor ID from the radio waves (S124: YES). The RFID reader / writer 60 transmits the received sensor ID to the user terminal 70. However, if the sensor unit 10 has some kind of malfunction, for example, the RFID reader / writer 60 may not be able to receive the sensor ID (S124: No). In this case, the RFID reader / writer 60 transmits radio waves for RFID tags (S123) until the number of retries exceeds a threshold (S131). If the sensor ID cannot be received before the number of retries exceeds the threshold (S124: No, S131: Yes), the RFID reader / writer 60 transmits a no-response message to the user terminal 70. Upon receiving this no-response message, the display processing unit 84 causes the display unit 73 to display an error message (S132).

[0092] When the communication processing unit 81 receives the sensor ID, the information management unit 83 obtains the sensor ID and determines the current time as the wearing time (S125). The display processing unit 84 causes the display unit 73 to display a sensor position input screen (S126). This input screen allows the user to specify whether the sensor unit 10 is positioned on the abdomen side or the back side relative to the absorbent article. If the position information of the sensor unit 10 is input (specified) through user operation on the input screen (S127: Yes), the information management unit 83 sets the received sensor ID, the wearing time determined in S125 and the input position information of the sensor unit 10 in the record of the wearer information table determined by the wearer ID of the designated wearer (S128).

[0093] Thus, according to this system, when an absorbent article is worn or replaced, not only the sensor ID and wearing time of the sensor sheet 1 worn are managed for each wearer, but also the positional information of the sensor unit 10 relative to the absorbent article is managed. By providing the positional information of the sensor unit 10, errors in the position and direction of the RFID reader / writer 60 can be suppressed, thereby preventing false detection of wetness of the absorbent article.

[0094] Figure 10 and Figure 11 Although a plurality of steps are shown in order, the execution order of the steps is not limited to the example shown in the figure and can be appropriately changed within a scope not departing from the gist.

[0095] [Modification] The contents of the above-mentioned embodiment are merely examples, and thus may be partially modified as appropriate. For example, in the aforementioned wetness detection system, the RFID reader / writer 60 and the user terminal 70 are separate components configured to communicate wirelessly with each other. However, the RFID reader / writer 60 and the user terminal 70 may also be implemented as a single device (hardware). In this case, the user terminal 70 is configured to include an antenna capable of transmitting and receiving radio waves for the RFID tag. In addition, the RFID reader / writer 60 may be implemented as a fixed type rather than a portable type. In the above-described wetness detection system, an example is shown in which the user terminal 70 includes the determination unit 82 . However, the server device 90 may include the determination unit 82 , and the user terminal 70 may mainly include the display processing unit 84 . In addition, in the above-mentioned wetness detection system, an example is shown in which multiple care receivers (wearers) are targeted, but a single wearer may be targeted. In this case, the wearer management DB 91 and the server device 90 are not required, and the designation process of designating the wearer is also not required.

[0096] A part or all of the above-mentioned embodiment and modified examples can also be defined as follows. However, the above-mentioned embodiment and modified examples are not limited to the following description.

[0097] <1> A wetness detection sensor sheet, the wetness detection sensor sheet is configured to be worn by a wearer as part of an absorbent article or to be worn by the wearer together with the absorbent article, the wetness detection sensor sheet having a sheet-shaped sensor portion and a water guide sheet, the sensor portion being configured to include an antenna portion and a communication portion and capable of wireless communication, the water guide sheet being overlapped and arranged on one side or both sides of the sensor portion, and being configured to extend from the wearer's abdomen side through the crotch portion to the back side when the wearer wears the absorbent article, the sensor portion being arranged closer to the area of ​​the water guide sheet corresponding to the abdomen side or the area corresponding to the back side than the area of ​​the water guide sheet corresponding to the crotch portion. <2> According to the above <1> The wetness detection sensor sheet further includes a first water-permeable sheet, a second water-permeable sheet and a deviation prevention sheet, the sensor portion and the water guide sheet are arranged between the first water-permeable sheet and the second water-permeable sheet, the sensor portion and the water guide sheet are arranged to be included in the first water-permeable sheet and the second water-permeable sheet when viewed from above, the deviation prevention sheet is arranged on the surface of the first water-permeable sheet or the second water-permeable sheet on the opposite side to the sensor portion and the water guide sheet, and is constructed to suppress the positional deviation of the wetness detection sensor sheet relative to the absorbent article, and the area of ​​the deviation prevention sheet that overlaps with the sensor portion when viewed from above has a width that occupies more than half of the entire deviation prevention sheet. <3> According to the above <2> In the wetness detection sensor sheet, the displacement prevention sheet is provided so as to be included in the sensor portion in a plan view. <4> According to the above <1> to <3> The wetness detection sensor sheet described in any one of the above is further provided with a water absorbing component, wherein the water absorbing component is arranged between the water guide sheet and the sensor part, and the sensor part further includes a wire part connecting the communication part and the antenna part, and is configured so that the antenna part or the wire part becomes disconnected according to the water absorption state of the water absorbing component. <5> A wetness detection sensor sheet kit, comprising a plurality of the above <4> The wetness detecting sensor sheet is configured such that the water absorbing members of the plurality of wetness detecting sensor sheets included in the wetness detecting sensor sheet set have different amounts of water absorbed to cause the antenna portion or the lead portion of the sensor portion to be disconnected. <6> A wetness detection system that can be used with the above <4> The wetting detection sensor sheet performs wireless communication, and the wetting detection system includes a terminal communication unit, a judgment unit, a display processing unit and a display unit. The terminal communication unit is configured to include an antenna and can perform wireless communication with the sensor unit through the antenna. The judgment unit is configured to judge whether the absorbent article is wet based on the wireless communication status between the terminal communication unit and the sensor unit. When the wireless communication status indicates a specific wireless communication status corresponding to the disconnection state of the sensor unit, the display processing unit causes the display unit to display an alarm display about the relationship between the position of the antenna relative to the absorbent article and the position of the sensor unit relative to the absorbent article. The judgment unit judges whether the absorbent article is wet based on the user operation on the alarm display. <7> A wetness detection system that can be used with the above <4> The wetness detection sensor sheet performs wireless communication. The wetness detection system includes a terminal communication unit, a determination unit, an information management unit, and an information storage unit. The terminal communication unit is configured to be capable of wirelessly communicating with the sensor unit. The determination unit is configured to determine whether the absorbent article is wet based on a wireless communication state between the terminal communication unit and the sensor unit. The information storage unit is configured to store, for each wearer of the absorbent article, wearer identification information, wearing time information, sensor identification information, and position information of the sensor unit in the absorbent article. The sensor unit has sensor identification information, and the terminal communication unit is configured to be capable of obtaining the sensor identification information from the sensor unit via wireless communication. The information management unit identifies the wearer identification information of the wearer specified by a user operation when the absorbent article is worn, causes the terminal communication unit to obtain the sensor identification information from the sensor unit, associates the sensor identification information with the determined wearer identification information, and stores the obtained sensor identification information, the wearing time information, and the position information of the sensor unit in the absorbent article in the information storage unit. The detailed description has been presented for purposes of illustration and description. Numerous variations and modifications are possible in light of the above teachings. The detailed description is not intended to be exhaustive or to limit the subject matter described herein. Although the subject matter has been described in terms of specific structural features and / or methodological procedures, it should be understood that the subject matter defined in the claims is not necessarily limited to the specific features or procedures described. Rather, the specific features and procedures described are described as examples of implementing the claims.

Claims

1. A wetness detection sensor sheet, characterized in that: The wetness detection sensor sheet is configured to be worn by a wearer as a part of an absorbent article or to be worn by the wearer together with the absorbent article. The wetness detection sensor sheet includes a sheet-shaped sensor portion and a water guide sheet. The sensor unit is configured to include an antenna unit and a communication unit, and is capable of wireless communication. The water guide sheet is overlapped and arranged on one side or both sides of the sensor portion, and is configured to extend from the abdomen side of the wearer through the crotch portion to the back side when the wearer wears the absorbent article. The sensor portion is provided on a side of a region corresponding to the abdomen or a side of a region corresponding to the back of the water guide sheet relative to a region corresponding to the crotch portion of the water guide sheet.

2. The wetness detection sensor sheet according to claim 1, wherein: The wetness detection sensor sheet further includes a first water-permeable sheet, a second water-permeable sheet, and a displacement prevention sheet. The sensor portion and the water guide sheet are disposed between the first water-permeable sheet and the second water-permeable sheet, and the sensor portion and the water guide sheet are disposed so as to be included in the first water-permeable sheet and the second water-permeable sheet in a plan view. The displacement prevention sheet is provided on a surface of the first water-permeable sheet or the second water-permeable sheet opposite to the sensor portion and the water guide sheet, and is configured to suppress positional displacement of the wetness detection sensor sheet relative to the absorbent article. A region of the deviation prevention sheet that overlaps with the sensor portion in a plan view has a width that occupies more than half of the entire deviation prevention sheet.

3. The wetness detection sensor sheet according to claim 2, wherein: The displacement prevention piece is provided so as to be included in the sensor portion in a plan view.

4. The wetness detection sensor sheet according to any one of claims 1 to 3, wherein: The wetness detection sensor sheet further includes a water absorbing member, and the water absorbing member is arranged between the water guide sheet and the sensor portion. The sensor unit further includes a lead portion connecting the communication unit and the antenna unit. The antenna portion or the lead portion is configured to be disconnected depending on the water absorption state of the water absorbing member.

5. A wetness detection sensor sheet kit, characterized in that: comprising a plurality of the wetness detection sensor sheets according to claim 4, The water absorbing members of the plurality of wetness detecting sensor sheets included in the wetness detecting sensor sheet set are configured so as to have different amounts of water absorbed to cause the antenna portion or the lead portion of the sensor portion to enter the disconnected state.

6. A wetness detection system, characterized in that: The wetness detection system is capable of wirelessly communicating with the wetness detection sensor sheet according to claim 4. The wetness detection system includes a terminal communication unit, a determination unit, a display processing unit, and a display unit. The terminal communication unit is configured to include an antenna and can communicate wirelessly with the sensor unit via the antenna. The determination unit is configured to determine whether the absorbent article is wet based on a wireless communication state between the terminal communication unit and the sensor unit. When the wireless communication state indicates a specific wireless communication state corresponding to the disconnected state of the sensor unit, the display processing unit causes the display unit to display a warning display regarding a relationship between a position of the antenna relative to the absorbent article and a position of the sensor unit relative to the absorbent article. The determination unit determines whether the absorbent article is wet based on a user operation in response to the warning display.

7. A wetness detection system, characterized in that: The wetness detection system is capable of wirelessly communicating with the wetness detection sensor sheet according to claim 4. The wetness detection system comprises a terminal communication unit, a determination unit, an information management unit and an information storage unit. The terminal communication unit is configured to be capable of wireless communication with the sensor unit. The determination unit is configured to determine whether the absorbent article is wet based on a wireless communication state between the terminal communication unit and the sensor unit. The information storage unit is configured to store wearer identification information, wearing time information, sensor identification information, and position information of the sensor unit in the absorbent article for each wearer of the absorbent article. The sensor unit has sensor identification information, The terminal communication unit is configured to acquire the sensor identification information from the sensor unit through wireless communication. When the absorbent article is worn, the information management unit determines the wearer identification information of the wearer specified by user operation, and causes the terminal communication unit to obtain the sensor identification information from the sensor unit, and associates the sensor identification information with the determined wearer identification information, and stores the obtained sensor identification information, the wearing time information, and the position information of the sensor unit in the absorbent article in the information storage unit.

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