WO2025209658A1

WO2025209658A1 - Hygiene monitoring device

Info

Publication number: WO2025209658A1
Application number: PCT/EP2024/059320
Authority: WO
Inventors: Henrik PETTERSSON-FALK; Geert Claassen
Original assignee: Essity Hygiene and Health AB
Current assignee: Essity Hygiene and Health AB
Priority date: 2024-04-05
Filing date: 2024-04-05
Publication date: 2025-10-09
Anticipated expiration: 2026-10-05

Abstract

A sensing panel (10) for a hygiene monitoring device (1) is provided, the sensing panel (10) comprising a longitudinally elongate, flexible substrate (11) defining a longitudinal axis (L) and a transverse axis (T), the elongate flexible substrate (11) comprising on one side of a longitudinal centerline of the substrate (11), a first set (12) of a plurality of first electrically conductive sensing plates (21, 22, 23, 24, 25, 26, 27), and on the opposite side of said longitudinal centerline of the substrate, a second electrically conductive sensing plate (28); the plurality of first sensing plates each being longitudinally elongated along the longitudinal axis, arranged mutually spaced apart from each other along the longitudinal axis and each defining a mutually exclusive length of the elongate flexible substrate; wherein the second sensing plate is longitudinally elongated along the longitudinal axis, is longitudinally longer than each one of the first plates, is positioned transversally spaced apart from each of the first electrically conductive plates and is arranged such that it extends into each of the length portions (L1,..., L7) of the substrate defined by the plurality of first sensing plates.

Description

HYGIENE MONITORING DEVICE

Field of Invention

The present disclosure relates to a sensing panel for a hygiene monitoring device, a hygiene monitoring device comprising such a sensing panel and a data logger unit releasably attached to the sensing panel, as well as a kit of parts comprising such a sensing panel and such data logger unit.

Background

Absorbent hygiene articles are used for addressing conditions such as leakage issues or incontinence. Such absorbent articles, mostly in the form of diapers, are likewise used for individuals but applied and managed by nursing personnel in the context of nursing homes, hospitals, and home care environments. In each such environment, the filling state, and the need for replacement of a full absorbent article, is of considerable interest, as well as the assessment of an individual’s specific voiding behavior.

There are techniques to detect the filling state of absorbent articles, such as diapers, that, amongst others, consider the use of conducting wires integrated into a diaper’s liquid absorbent layer. As the sensor arrangement is integrated and hard-wired with the absorbent article, it needs to be disposed of once the absorbent article is full or needs replacement. At the same time, the measurement of voiding behavior and related figures, such as voiding volume and timings, is usually of interest for prolonged time spans. An initial assessment regarding a likely voiding pattern requires at least several days or weeks of monitoring, while the long-term application in nursing homes under a replacement alert regime requires sensors on an everyday basis.

There is the desire to decouple the sensor arrangement from the absorbent article as such, so that the former can be reused several times, while the latter can be disposed of whenever required at keeping the involved cost low.

Approaches to reusable sensors for qualitatively detecting the presence and/or quantitively assessing the amount of liquid absorbed by a hygiene absorbent article are describe, inter alia in W02020/126000, that discloses impedance-based measurement using plane-parallel capacitors. However, there is a desire in the art to improve the resolution and precision of the reusable sensors without significantly increasing the cost. Summary of Invention

One object of the present disclosure is to provide hygiene monitoring sensors, as well as components for such hygiene monitoring sensors, that at least partly meet the needs in the art.

In one aspect, the present disclosure relates to a sensing panel for a hygiene monitoring device. The sensing panel comprises a longitudinally elongate, flexible substrate defining a longitudinal axis and a transverse axis. On one side of a longitudinal centerline of the substrate the elongate flexible substrate comprises a first set of a plurality of first electrically conductive sensing plates. On the opposite side of said longitudinal centerline of the substrate, the elongate flexible substrate comprises a second electrically conductive sensing plate. Each of first sensing plates are being longitudinally elongated along the longitudinal axis, arranged mutually spaced apart from each other along the longitudinal axis and each defining a mutually exclusive length portion of the elongate flexible substrate. The second sensing plate is longitudinally elongated along the longitudinal axis, is longitudinally longer than each one of the first plates, is positioned transversally spaced apart from each of the first electrically conductive plates and is arranged such that it extends into each of the length portions of the substrate defined by the plurality of first sensing plates.

The second sensing plate may be co-extensive with each one of the first sensing plates.

The plurality of first sensing plates may consist of at least 4 plates, such as from 4 to 15 plates, such as from 5 to 10, such as from 6 to 8 plates.

Each one of the first sensing plates may have a transversal width of from 2 to 20 mm, such as from 4 to 10, such as from 6 to 8 mm.

Each one of the sensing plates may have longitudinal length of from 20 to 100 mm, such as from 30 to 80, such as from 40 to 60 mm.

Adjacent first sensing plates may be longitudinally spaced apart by from 1 to 10 mm, such as from 4 to 8 mm.

Each one of the first sensing plates may be aligned along a common longitudinal line.

The second sensing plate may have a transversal width of from 2 to 20, such as from 4 to 10, such as from 6 to 8 mm.

The second sensing plate may have a longitudinal length of from 150 to 1000, such as from 250 to 700 mm, such as from 300 to 500 mm.

Each one of the first sensing plates may be parallel to the second sensing plate. The sensing panel may comprise a panel side terminal portion, wherein each one of the first sensing plates and said second sensing plate are individually electrically connected via electrically conductive traces to respective contact terminals of the panel side terminal portion.

Each one of the first sensing plates and the second sensing plate may disposed on one side of the flexible substrate and an electrically conducting grounding plate may be disposed on the other (opposite) side of the flexible substrate.

The grounding plate may be electrically connected via an electrically conductive traces to one of the contact terminals of the panel side terminal portion.

The electrically conductive traces may be mainly disposed on the side of the flexible substrate opposite to the one on which the first and second sensing plates are arranged.

A flexible substrate may on one major surface of the flexible substrate, preferably the surface on which the first and second sensing panels are provided, be provided with an attachment material, such as for allowing the sensing panel to be removably attached to an outer surface of an absorbent hygiene article.

The sensing panel may comprise a receptacle for a data logger unit, the data logger unit comprising a plurality of contact terminals of a logger side terminal portion, and the receptable and the data logger unit being adapted such that when the data logger unit is engaged with the receptacle, the logger side terminal portion is aligned to the panel side terminal portion to establish contact between contact terminals of the panel side terminal portion and contact terminals of the logger side terminal portion.

In another aspect, the present disclosure relates to a hygiene monitoring device comprising a sensing panel and a data logger unit, both as defined herein, wherein the data logger unit is, optionally removably, attached to said sensing panel and electrically connected to the plurality of first sensing plates and to the second sensing plate and adapted to measure an impedance between each one of said first sensing plates and said second sensing plate.

The sensing panel may be adapted to be associated with a garment facing surface of an absorbent hygiene article, and may be adapted to assess a liquid content absorbed by said absorbent hygiene article, where said assessment is at least partly based on an impedance measured between each one of said first electrically conductive plates and said second electrically conductive plate.

In yet another aspect, the present disclosure relates to a kit of parts for a hygiene monitoring device, comprising a sensing panel as defined herein and a data logger unit adapted to be removably attached to said sensing panel and electrically connected to the plurality of first sensing plates and to the second sensing plate and adapted to measure an impedance between each one of said first sensing plates and said second sensing plate.

Brief Description of Drawings

Embodiments of the present invention, which are presented for better understanding the inventive concepts, but which are not to be seen as limiting the invention, will now be described with reference to the figures in which:

Figure 1 illustrates a hygiene monitoring device of an embodiment of the invention attached to a garment facing surface of an absorbent hygiene article;

Figure 2a illustrates an exploded, perspective view of a sensing panel of an embodiment of the invention;

Figure 2b illustrates an assembled hygiene monitoring device of an embodiment of the invention, comprising a sensing panel and a data logger unit attached thereto;

Figure 3a illustrates a top view of a flexible substrate of an embodiment of the invention;

Figure 3b illustrated a detail of the flexible substrate of figure 3a, seen from the other side;

Figure 4a illustrates a perspective view of a data logger unit of an embodiment of the invention;

Figure 4b illustrates another perspective view of a data logger unit shown in Fig 4a;

Figure 5 illustrates a data logger unit and a wash lid of an embodiment of the invention.

Detailed Description

Figure 1 illustrates an absorbent hygiene article 100 and a hygiene monitoring device 1 according to an embodiment of the present invention attached to an outer, garment facing side 101 of the absorbent hygiene article 100.

The hygiene monitoring device 1 is a multi-component device able to monitor at least one hygiene related state of the absorbent hygiene article 1 , such as for example detect the presence or assess the quantity of liquid exudates absorbed in an absorbent core of the absorbent hygiene article 100, and comprises a sensing panel 10 and a data logger unit 60 that is attachable, preferably removably attachable, to the sensing panel 10. Details of each of these components will be described in the following.

In the context of this disclosure, the term “absorbent hygiene articles” is intended to include any absorbent hygiene article such articles like diapers, training pants, incontinence pads and sanitary pads and pants that are intended to receive, absorb, and contain body exudates, notably urine, feces, and menstrual fluid, and that contain one or more absorbent core or layer(s). The term is intended to cover all variants of such articles, both disposable and washable articles as well as articles consisting partly of disposable parts and partly of reusable parts.

An embodiment of the hygiene monitoring device is illustrated in Figures 2a-b, comprising a sensing panel 10 and attached thereto a data logger unit 60 comprising electronics for measurement and data logging purposes. The hygiene monitoring device 1 of this embodiment is intended to detect the presence of or assess the quantity of body exudates, such as urine, in the absorbent core of an absorbent hygiene article, or to assess the level of saturation of the absorbent core, by means of impedance measuring.

The sensing panel 10 is flexible, e.g., bendable, such as in the sense that it can conform to the curvature of the outer surface of an absorbent hygiene article without breaking, and comprises a longitudinally elongate, flexible, e.g., bendable, substrate 11 that defines a defining a longitudinal axis (L) and a transverse axis (T). The sensing panel 10 typically also has a longitudinally elongate shape.

The sensing panel 10 of the hygiene monitoring device 1 is typically intended to extend into the crotch area, i.e. , between the legs of the user. In that area, there is a desire for the sensing panel to be relatively narrow, i.e. having a limited transverse width. Suitably, the sensing panel is therefore from 1 to 5, such as from 2 to 4 cm, wide in the transversal direction.

The sensing plate 10 may comprise a flexible substrate 11 comprising one or more sensor components, and a receptacle 50 for engaging with the data logger unit 60 to removably attaching it to the sensing panel 10.

The elongate flexible substrate 11 is illustrated more in detail in figure 3a, there viewed from the side of the substrate 11 that is intended to face the surface of the absorbent hygiene article. The flexible substrate 11 is elongate in the sense that it is significantly longer (as measured along the longitudinal axis L) than it is wide (as measured along the transversal axis T). Typically, the flexible substrate is at least 10 times, such as at least 15 times, as long as it is wide. The width may for example be in the range of from 2, such as 3, to 5, such as 4 cm, whereas the length may be in the range of from 20 to 50 cm.

The flexible substrate 11 is typically a flexible printed circuit board substrate, flex-PCB substrate, made from conventional materials for flex-PCB substates, such as polyimide or polyester.

The flexible substrate 11 comprises on one side of a longitudinal centerline CL a set of a plurality of first electrically conductive sensing plates 21 , 22, 23, 24, 25, 26, 27, and on the opposite side of said longitudinal centerline of the substrate, a second electrically conductive sensing plate 28. Pairs of sensing plates 21 , 28; 22, 28; ... ; 27,28 acts as the plates of an open face capacitor. By measuring the impedance between each of the first sensing plates 21-27 and the second sensing plate 28, the presence or absence of liquid in the absorbent core of the absorbent hygiene article 100 may be determined (as described more in detail elsewhere in this document). Without wishing to be bound by theory, the presence of liquid such as urine in the absorbent article modifies the dielectric constant of the region of the absorbent article covered by the sensing panel, for instance modifying the dielectric constant of the region covered by plates 22 and 28, thereby affecting the impedance of the capacitor formed by that pair of plates 22, 28.

Such a configuration allows the detection of liquid in the absorbent core in a non-contact manner, in the sense that there is no direct, galvanic, contact between the body fluids and the sensing plate. Accordingly, sensing panel 10 can sense the state of an absorbent core or region of an absorbent core even when separated from the absorbent core by a liquid impermeable layer such as a liquid impermeable back sheet. This is in contrast, for example, to resistive-type sensing arrangements which tend to require galvanic contact between the liquid in the absorbent core and conductors which act as sense elements.

By arranging the set of first sensing plates 21-27 and the second sensing plate 28 as described herein, a high spatial resolution along the longitudinal direction for the impedancebased measurement can be obtained while keeping the number of channels of the impedance measurement electronics, necessary for performing the measurements, low. The second sensing plate 28 is common for the impedance measurement at all locations along the longitudinal extension of the sensing panel 10, while each one of the first sensing plates 21- 27 represents essentially the location of the absorbent core covered by the respective length portion L1-L7. In that sense, the spatial resolution for a set number of available measurement channels is optimized, and the cost for and the power consumption of the impedance measurement electronics can be kept down. For example, for a total of 8 available measuring channels, a desired resolution of 7, i.e., the ability to measure the impedance and thereby locally detecting the presence of liquid in the absorbent hygiene article at 7 different locations along the longitudinal extension of the sensing panel 10, can be obtained.

Throughout this disclosure the measurement of impedance may optionally be a measurement and/or a calculation of the magnitude of the impedance.

The sensing plates are made of an electrically conducting material suitable for being arranged on the flexible substrate, such as metal, e.g., copper or silver, conductive polymeric material, or conductive carbon. The sensing plates of electrically conducting material are provided on a surface of the flexible substrate 11 by conventional methods in the art suitable for the material in question. For example, metal plates may be provided by roll-anneal or electrodepositing methods.

The sensing plates 21 , ... , 27 in the plurality of first sensing plates are each being longitudinally elongated along a longitudinal axis of the flexible substrate and are arranged mutually spaced apart from each other along the longitudinal axis L. Each of the first sensing plates defines a mutually exclusive length portion L1 , L2, L3, L4, L5, L6, L7 of the elongate flexible substrate 11 , i.e., no one of the first sensing plates overlap, longitudinally, any other one of the first sensing plates.

The first sensing plates 21 , ... , 27 may be arranged with their longitudinal axis parallel to the longitudinal axis of the flexible substrate. The first sensing plates 21 , ... , 27 may arranged after each other along a common longitudinal line. In the embodiment depicted in figure 3a, the plurality of first sensing plates comprises 7 sensing plates. However, the invention is not limited to this, and the plurality of first sensing plates may inter alia comprise from 4, 5 or 6 to 15, 10 or 8 plates, for example 7 plates.

The first sensing plates 21 , ... , 27 may each have a transversal width of from 2, 4, or 6 to 20, 10 or 8 mm and/or may each have longitudinal length of from 20, 30 or 40 to 100, 80, or 60 mm. The first sensing plates may have the same or different transversal widths and/or longitudinal lengths.

The plates in pairs of adjacent first sensing plates, e.g., 21 and 22; 22 and 23; 23 and 24; 24 and 25; 25 and 26; 26 and 27, may be longitudinally spaced apart by from 1 , 2, 3, 4 or 5 to 10, 9, 8 or 7 mm. The spacing between different pairs may be the same or different.

The second sensing plate 28 is longitudinally elongated along the longitudinal axis L, and is positioned transversally spaced apart from each of the first sensing plates 21 , ... , 27. The second sensing plate is longitudinally longer than each one of the first sensing plates 21 ,... , 27 and is arranged such that it extends into each of the length portions L1 , ... , L7 of the substrate defined by the plurality of first sensing plates. In other words, for each one of the first sensing plates, a portion of the second sensing plate is located directly transversal in relation to that first plate.

The second sensing plate 28 may be aligned with its longitudinal axis parallel to the longitudinal axis of the flexible substrate, for example with each one of the first sensing plates 21 , ... , 27 being parallel to the second sensing plate 28. The second sensing plate 28 may have a transversal width of from 2 to 20, such as from 4 to 10, such as from 6 to 8 mm and/or may have a longitudinal length of from 150, 250 or 300 to 1000, 700 or 500 mm.

The transversal width of the second sensing plate 28 may be substantially equal to that of the first sensing plates 21 , ... , 27.

The distance, in the transversal direction of the flexible substrate, between the second sensing plate 28 and the first sensing plates 21 , ... , 27 may be from 2, 3, 4, or 5 to 10, 9, 8 or 7 mm.

The plate width and the transversal distance between the first sensing plates and the second plate influences the electrical field created when measuring the impedance between the plates and may therefore need to be adapted in order for the hygiene monitoring device to be able to sense a change in the absorbent hygiene article 100.

For instance, the ratio between the transversal width of the second sensing plates and the distance between the second sensing plate 28 and a first sensing plates 21-27 may be in the range of from 0.5 to 2.

As in the embodiment illustrated in figure 2, the second sensing plate 28 may be coextensive with each one of the first sensing plates 21 , ... , 27 such that the second sensing plate runs parallel to the full extension of each one of the first sensing plates. Alternatively, the second sensing plate only runs parallel to part of one or both or the first sensing plates being most distant from each other.

Essentially, the shortest one of the longitudinal length of the second sensing plate and the longitudinal length portion (end-to-end) covered by the first sensing plates determine an effective sensing length for the hygiene monitoring device, i.e. how large length of the absorbent hygiene article that can be monitored.

Depending on the intended user, capacity requirements and type of absorbent hygiene article, the length of the absorbent article and the absorbent structure/core may differ, putting different requirements on the effective sensing length for the sensing panel.

An effective sensing length of from 300 to 500, such as from 350 to 550 mm has, however, been shown to represent a length that can be used in a large range of applications for adult incontinence products.

An electrically conductive grounding plate 29 may be arranged on the opposite side of the flexible substrate 11 from the side on which the sensing plates are arranged, i.e. on the side of the flexible substrate that, when in use, is intended to face away from the absorbent hygiene article 100. The grounding plate 29 may cover parts of or substantially all of the surface of flexible substrate 11 , but preferably covers significant parts of that region which bears the sensing plates 21-28. For example, such a grounding plate may be implemented by a meshlike pattern of a conductive material.

Using a grounding plate 29 disposed on the opposite side of the sensing plates 21-29 results in the electric fields between the plates being largely localized to only one side of the hygiene monitoring device.

Thereby, the influence on the impedances between pair of plates 21 , 28; 22, 28; ... ; 27, 28 may predominantly be controlled by the environment above the surface of the flexible substrate 11 carrying the sensing plates, rather than by the environment adjacent to the opposite side of flexible substrate 11.

Accordingly, the measurements carried out by the hygiene monitoring device 1 are primarily sensitive to only one side of the device, which means that the dielectric constant and resistance on the other side of the device does not significantly impact the measured impedance.

The dielectric constant and resistance on the other side of the plates may tend to change frequently (for example, due to a change in clothing worn by the user). However, with the above configuration, the measured impedance is not significantly affected by these changes, which results in improved accuracy of detection.

In certain embodiments, the grounding plate partially or fully overlaps the plates in the plane of the flexible substrate.

As is shown in figure 3b, each one of the sensing plates 21-28, and when present, the grounding plate 29, may be connected by a respective conductive trace 31 to respective panelside contact terminals 32 arranged in a panel-side terminal region 30 of the sensing panel 10 on the flexible substrate 11.

The panel-side terminal region 30 may be located in the area of the flexible substrate overlaying, superimposed on, the baseplate 51 of the receptacle 50.

The conductive traces 31 are provided on a surface of the flexible substrate and may, as well as plates 21-29 may be covered by a layer of dielectric material such a thin film on polymer. In contrast, the panel-side contact terminals 32 may be exposed at the surface of flexible substrate 11 to act as terminals facilitating connection between plates 21-29 and measurement and data logging electronics, to be described later. The conductive traces 31 may advantageously be provided on the opposite side of the flexible substrate from the side on which the sensing plates 21-28 are arranged, and may in such case be connected to the sensing plates through vias in the flexible substrate 12. Being provided on this opposite side of the flexible substrate 11 , at least some of the conductive traces may extend directly under the first sensing plates. This may be advantageous in keeping the width of the flexible substrate 11 as low as possible. By avoiding placing all the conductive traces 31 on the sides of the sensing pads, the width of the sensing plates 21-28 in relation to the width of the flexible substrate 11 can be maximized.

Further, while the conductive traces 31 typically run, for a major part of their extension, in parallel from the panel side terminal portion 30 to the respective one of the sensing plates 21 ,... ,28, it may be advantageous to arrange the conductive traces in a nested arrangement, such that the conductive traces to adjacent sensing panels are not running next to each other. This may help to reduce cross-talk effect between the conductive traces.

Panel-side contact terminals 32 may be provided within a panel-side terminal region 30 of the flexible substrate to enable connection between plates 21-29 and a data logger unit 60 comprising measurement and data logging electronics, to be described later, by means of corresponding logger-side contact terminals 68 on the data logger unit 60.

The panel-side contact terminals 32 may for example be conductive contact pads suitable for establishing contact with corresponding pogo-pins on the data logger unit, or vice versa with the pogo-pins on the panel side and the contact pads on the logger side. Other terminal arrangements include, for example, mezzanine connectors, plug-and-socket connectors, registered jack or modular connectors, tip-ring-sleeve connectors, D-subminiature connectors, DIN connectors, or other terminal or connector types as known in the art.

The panel-side contact terminals 32 are typically accessible from that side of the flexible substrate opposite to the side on which the sensing plates 21-28 are arranged, since the data logger 60, when attached to the sensing panel, typically faces away from the absorbent hygiene article 100.

A hygiene monitoring device 1 may be configured to associated with an absorbent hygiene article 100. In the context of this application “associated with” implies that the hygiene monitoring device, when associated with the absorbent hygiene article is able to measure properties within the absorbent hygiene article, such as assessing or quantifying the amount of body fluid absorbed by the absorbent hygiene article’s absorbent core.

Typically, the hygiene monitoring device 1 is to be kept in close proximity of, held against or attached to, optionally removably attached to, an outer surface of 101 the wearable absorbent hygiene article. In certain embodiments, the hygiene monitoring device is removably attachable to an outer surface, e.g. to the outside or a back sheet of an absorbent article. Alternatively, the hygiene monitoring device may be held against or in proximity to the outer surface of the absorbent hygiene garment by means of an auxiliary device, such as held in place by an auxiliary garment.

When used, the hygiene monitoring device 1 is typically to be aligned with its longitudinal axis generally parallel to the longitudinal extension of the absorbent hygiene article, with one end of the hygiene monitoring device 1 towards the front or waist region of the absorbent hygiene article 100, and the other end of the hygiene monitoring device 1 towards the back or rear region of the absorbent hygiene article 100, as is shown schematically in figure 1.

As illustrated in figure 2a, the sensor panel 11 may be provided with a hook material 15, configured to be removably attachable to the outer surface 101 , e.g. back-sheet, of wearable absorbent hygiene article 100. In general, where the hygiene monitoring device 1 is to be attachable to the outer surface of the absorbent hygiene article, the side of the sensing panel 11 on which the sensing plates 21-28 are arranged is provided with an attachment material 15 over at least part of the surface of the sensing panel. Suitable attachment materials include for example pressure sensitive adhesives and hook-components suitable to interact with the outer surface of the absorbent hygiene article.

The sensing panel 10 may comprise a receptacle 50 adapted to releasably attach a data logger unit 60 containing measurement and data logging electronics, as will be described later, to the sensing panel 10.

The receptacle 50 and the data logger unit 60 are mutually adapted such that when the data logger 60 is engaged with the receptacle 50, it is securely and releasably attached to, held in place in, the receptacle, and advantageously, a plurality of contact terminals 68 of a logger side terminal portion 61 is establishing electrical contact between the data logger 60 and the sensing plates via the above-described terminals 32 of the panel-side terminal portion 30.

The receptacle 50 may be positioned closer to a longitudinally outermost edge of the sensing panel 10 than to the longitudinal center of the sensing panel 10, especially such that the data logger unit, when attached to the sensing panel, is positioned relatively close to one end of the sensing panel 10, and the hygiene monitoring device 1 is adapted to be worn with the data logger unit 60 positioned towards the front waist region of the absorbent hygiene article. The flexible sensing panel may, however, extend longitudinally beyond both longitudinal outermost edges of the data logger unit. Such receptacle 50 may comprise a base plate 51 with a logger facing side 52, i.e. the side of the base plate that is to face the data logger unit 60 when correctly attached to the receptacle 50.

The receptacle 50 may be arranged on the sensing panel 10 such that a portion of the flexible substrate 11 is arranged on the base plate 51. The flexible substrate 11 may be attached to the logger-facing side of the baseplate by suitable adhesives 14, such as e.g., double-sided tapes.

An elastic layer 13 of an elastic, water-impermeable material may be provided on the flexible substrate 11 such that the flexible substrate 11 is sandwiched between the layer 13 and the base plate 51 of the receptacle 50. This material 13 is intended to contact with and provide a seal against the data logger 60 when the data logger unit 60 is engaged with the receptacle 50, to prevent liquid to enter the area immediately between the sealing layer 13 and the data logger unit 60. This is especially useful in embodiments as shown in figures 2a-b and 4a-b, where the data logger unit 62 presents an opening 65 on the panel-facing side, as will be described later. In such cases, the elastic sealing layer 13 provides a water-tight sealing around that opening 65 to prevent water from entering into interior of the data logger unit 62.

The elastic sealing layer 13 may be provided on top of the flexible substrate 11 , at least on the portion of the flexible substrate 11 that is arranged intended to be superimposed on the base plate 51 , and is advantageously covering also those parts of the flexible substrate 11 that extend outside the base plate 51 , e.g. acting as a protective layer for the flexible substrate 11. The elastic sealing layer 13 may extend slightly beyond the edges of the flexible substrate 11 around essentially the whole perimeter of the flexible substrate, e.g., to protect a user from the usually sharp edges of the flexible substrate 11.

The elastic layer 13 is typically made of an elastomeric material such as thermoplastic or thermoset elastomers. Examples of thermoplastic elastomers include styrenic block copolymers, TPS (TPE-s), thermoplastic polyolefin elastomers, TPO (TPE-o), thermoplastic vulcanizates, TPV (TPE-v or TPV), thermoplastic polyurethanes, TPU (TPU), thermoplastic copolyester, TPC (TPE-E) and thermoplastic polyamides, TPA (TPE-A). Examples of thermoset elastomers include natural rubber, styrene-butadiene rubber (SBR), nitrile rubber (NBR), butyl rubber (HR), ethylene propylene diene monomer (EPDM), and silicone rubber.

The thickness of the elastic sealing layer 13 is tailored to provide proper sealing effect while also contributing to a suitable flexibility of the sensing panel. The thickness may be in the range of from 0.2 to 2 mm as measured without applying any pressure on the elastic sealing layer. The elastic sealing layer 13 may be attached to the surface of the flexible substrate by suitable adhesives 12, such as e.g., double sided tapes, for example acrylic adhesive based double sided adhesives.

The receptacle 50 may be provided with receptacle side engaging means 54, for example extending from edges of the base plate 51 in the logger-facing direction, so as to engage with a logger-side engaging means 66 of a data logger unit 60 intended to be releasably attached to the sensing panel 10.

Advantageously, the logger-side engaging means 66 and corresponding receptacle-side engaging means 54 interact to provide a snap-fit action between the data logger unit 60 and the receptacle 50, such that the data logger unit 60 is pressed against the elastic layer 13. Even more advantageously, the data logger unit 60 is relatively easily fit into the receptacle 50 by pressing them together by the pinching force of a hand, while a significantly higher force, or a tool, is needed to separate the data logger unit 60 from the receptacle.

A through-hole 16 may be provided in the sealing layer 13 and any intermediate layer between the sealing layer and the flexible substrate, such as e.g., an adhesive layer 12, to provide access for the logger side terminal portion 61 to connect to the panel-side terminal portion 30 when a data logger unit 60 is attached to the sensing panel 10. The through-hole 16 is advantageously located in a position overlaying the receptacle base plate 51 such that liquid is prevented to enter the connection between the logger side terminal portion 61 and the panel-side terminal portion when the logger unit 60 is correctly attached to the sensing panel 10.

The hygiene monitoring device 1 comprises a data logger unit 60 which comprises electronics for measurement and data logging purposes, as is illustrated in figures 4a-b.

Importantly, the sensing panel 10 is unable on its own to monitor the absorbent state of a hygiene absorbent article. To allow sensing panel to monitor the absorbent state of an absorbent article, it is combined with a data logging unit 60, such that the data logging unit 60 is able to supply electrical signals to sensing panel 10 and to measure changes in the electrical properties of the sensing panel 10.

The data logging unit 60 may comprise electronics for impedance measurements such that when connected to the sensing panel 10 the combination forms a hygiene monitoring device 1 able to measure the impedance within an absorbent hygiene article 100 to detect the presence of and/or quantify the amount of body exudates, such as urine, absorbed in the absorbent core of the absorbent hygiene article 100. The electronics for impedance measurements may for example comprise a ADuCM350 chip available from Analog Devices, Wilmington, MA

The data logging unit 60 may be provided in association with a remote terminal, which may be a portable computing device such as a laptop, smartphone, or which may be a server or virtual server. The data logging unit may be connected by a wireless link to the remote terminal in order to periodically, on demand, or on detection on the change of absorbent status, signal the remote terminal in order to provide the results of the measurement to the remote terminal.

The data logging unit 60 alternatively may be a stand-alone data logging unit, which is equipped with a memory to which periodic measurements are stored. These periodic amendments may be later downloaded from the data logger to a management console, for example a personal computer, to evaluate a pattern of the absorbent state of the absorbent article over time. The data logging unit may be provided with a data retrieval interface such as a USB port for downloading over a wired connection or may be provided with a short-range wireless data retrieval interface such as a Bluetooth module for downloading over a wireless configuration.

Alternatively, the data logging unit 60 may measure the state of the absorbent article and may temporarily retain information about the state of the absorbent article in order to provide a notification on a change in the state of the absorbent article, for example by providing an audible (for example by a buzzer) or visible (for example by a light emitting diode, or LED) output signal from the data logging unit.

The data logger unit 60 is connectible to the sensing plates on the sensing panel, such as via logger side terminals 68 of a logger side terminal portion 61 that established electrical contact between the data logger 60 and the sensing plates via the above-described terminals 32 of the panel side terminal portion 30. When the data logger unit is correctly attached to the sensing panel 10 by means of the receptacle 50, the logger-side terminal portion 61 mates with, i.e. aligns to, the panel side terminal portion 30 such that the electrical contact between the logger side terminals 68 and the panel side terminal 32 can be established. The logger side terminals 68 and the panel side terminals 32 are selected such that they establish a reliable electrical connection. For instance, the logger side terminals 68 may be pogo-pins and the panel side terminals 32 may be conductive pads. Other combinations of logger side terminals and panel side terminals are also possible, as described above in connection to the panel side terminals. The data logger unit 60 may comprise a housing 62, typically of a plastic material, and may be made of a single component or may comprise several housing components joined together.

The housing 62 encloses an interior 63, within which the electronics for measurement and data logging purposes and other components, such as a battery and a battery holder may be provided.

As illustrated in figure 4a-4b, the housing 62 may define a panel facing surface 64, i.e. the surface of the housing 62 that faces the sensing panel 12 when attached thereto, such as when engaged with a receptacle 50.

The panel facing surface 64 of the data logger unit 60 may be provided with an opening 65 for providing access to at least part of the interior 63 of the housing 62. Especially, such opening 65 may provide access to a battery holder and is big enough for replacing a battery, for example a button cell battery of conventional type, for powering the data logger unit through this opening, without further opening up the housing.

In order to properly engage with a receptacle 50, the data logger unit housing 62 may present logger-side engaging means 66 intended to interact with corresponding receptacleside engaging means 54 of the receptacle. The logger side engaging means 66 may for example be in the form of recesses or indentations in the housing 62 adapted to interact with corresponding elements 54 protruding from the receptacle 50. Advantageously, the loggerside engaging means 66 and corresponding receptacle-side engaging means 54 interact to provide a snap-fit action between the data logger unit 60 and the receptacle. Even more advantageously, the data logger unit 60 is relatively easy to fit into the receptacle 50 by pressing them together by the pinching force of a hand, while a significantly higher force, or a tool, is needed to separate the data logger unit 60 from the receptacle.

The panel facing surface 64 of the data logger unit 60 may be provided with a ridge-like protrusion 67 protruding from the surface and encircling the opening 65 and/or logger side terminal portion 61. Alternatively, one ridge may encircle the opening 65 and another ridge may encircle the logger side terminal portion 61.

The ridge-like protrusion 67 may press into the elastic layer 13 of the receptacle when the data logger unit 60 is attached to the receptacle 50, so as to provide a more secure watertight seal between what is inside and outside the ridge.

A wash lid 150 as shown in figure 5 may be provided separately or together with the hygiene monitoring device 1. The wash lid 150 comprises a receptacle with essentially the same function and material selections as a receptacle of the sensing panel 10, however not comprising a flexible substrate 11. To that end, the wash lid 150 comprises a base plate 151 with a logger facing side 152 and an elastic layer 153 arranged on the logger facing side 152, and further comprising wash lid-side engaging means 154 intended to interact with corresponding logger-side engaging means 66 of a data logger unit 60 intended to be releasably attached to wash lid 150. Whereas in the sensing panel 10, the elastic layer 13 may extend outside the base-plate 51 of the receptacle 50 to protect one surface of the flexible substrate 11 also outside the receptacle 50, in the wash lid 150, the elastic layer 153 may be limited in its extension to the area of the logger-facing side 152 of the baseplate 151 , thereby making the wash lid 150 more compact in size compared to the sensing panel 10.

The wash lid 150 is intended to be used when the data logger unit 60 is to be washed, e.g., after being soiled, or when the data logger unit 60 is to be used by a new caretaker, i.e. acting a lid for the data logger 60 during washing (wash lid). The data logger 60 is, optionally after being removed from a sensing panel 11 , attached to the wash lid via interaction between the wash lid-side engaging means 154 and corresponding logger-side engaging means 66 such that the data lugger unit contacts and presses against the elastic layer 153. In the same manner as described above in connection to the elastic layer 13 on the sensing panel 10, also the elastic layer 153 of the wash lid 150 provide a seal against the data logger unit 60 when the data logger unit 60 is attached to the wash lid, to prevent liquid to enter the area immediately between the sealing layer 153 and the data logger unit 60. This is especially useful where the data logger unit 62 presents an opening 65 on the panel-facing side. In such cases, the elastic layer 153 provides a sealing around that opening 65 to prevent water from entering into interior of the data logger unit 60. Therefore, when the data logger unit 60 is attached to the wash lid 150, it can be thoroughly cleaned without being attached to a sensing panel 10, and at the same time without the risk of water or contaminants entering the interior 63 of the data logger unit 60, which could be detrimental to any electronic components housed in the data logger unit.

Claims

1. A sensing panel (10) for a hygiene monitoring device (1), the sensing panel (10) comprising: a longitudinally elongate, flexible substrate (11) defining a longitudinal axis (L) and a transverse axis (T), the elongate flexible substrate (11) comprising on one side of a longitudinal centerline (CL) of the substrate (11) , a first set (12) of a plurality of first electrically conductive sensing plates (21, 22, 23, 24, 25, 26, 27), and on the opposite side of said longitudinal centerline of the substrate, a second electrically conductive sensing plate (28); each one of the plurality of first sensing plates (21, ... , 27) being longitudinally elongated along the longitudinal axis, arranged mutually spaced apart from each other along the longitudinal axis (L) and each defining a mutually exclusive length portion (L1, L2, L3, L4, L5, L6, L7) of the elongate flexible substrate (11); wherein the second sensing plate (28) is longitudinally elongated along the longitudinal axis (L), is longitudinally longer than each one of the first plates (21, ... , 27), is positioned transversally spaced apart from each of the first electrically conductive plates (21, ... , 27) and is arranged such that it extends into each of the length portions (L1, ... , L7) of the substrate defined by the plurality of first sensing plates.

2. The sensing panel according to claim 1, wherein said second sensing plate (28) is coextensive with each one of the first sensing plates (21, ... , 27).

3. The sensing panel according to any one of the preceding claims, wherein the set of plurality of first sensing plates comprises at least 4 plates, such as from 4 to 15 plates, such as 5 to 10, such as 6 to 8 plates.

4. The sensing panel according to any one of the preceding claims, wherein the first sensing plates (21 , ... , 27) each have a transversal width of from 2 to 20 mm, such as from 4 to 10, such as from 6 to 8 mm.

5. The sensing panel according to any one of the preceding claims, wherein the sensing plates (21, ... , 27) each have longitudinal length of from 20 to 100 mm, such as from 30 to 80, such as from 40 to 60 mm.

6. The sensing panel according to any one of the preceding claims, wherein adjacent first sensing plates (21, 22; 22, 23; ... ; 26,27) are longitudinally spaced apart by from 1 to 10 mm, such as from 4 to 8 mm.

7. The sensing panel according to any one of the preceding claims, wherein each one of the first sensing plates (21 , ... , 27) are aligned along a common longitudinal line.

8. The sensing panel according to any one of the preceding claims, wherein the second sensing plate (28) has a transversal width of from 2 to 20, such as from 4 to 10, such as from 6 to 8 mm.

9. The sensing panel according to any one of the preceding claims, wherein the second sensing plate (28) has a longitudinal length of from 150 to 1000, such as from 250 to 700 mm, such as from 300 to 500 mm.

10. The sensing panel according to any one of the preceding claims, wherein each one of the first sensing plates (21, ... , 27) are parallel to the second sensing plate (28).

11. The sensing panel according to any one of the preceding claims, comprising a panel side terminal portion (30), and wherein each one of the first sensing plates

(21, ... , 27) and said second sensing plate (28) are individually electrically connected via electrically conductive traces (31) to respective contact terminals (32) of the panel side terminal portion (30).

12. The sensing panel according to any one of the preceding claims, wherein each one of the first sensing plates (21 , ... , 27) and said second sensing plate (28) are disposed on one side of the flexible substrate (11), and wherein an electrically conducting grounding plate (29) is disposed on the other side of the flexible substrate (11).

13. The sensing panel according to any one of the preceding claims, wherein the grounding plate (29) is electrically connected via an electrically conductive trace (31) to one of the contact terminals (32) of the panel side terminal portion (30).

14. The sensing panel according to any one of the claims 12 or 13, wherein the electrically conductive traces (31) are mainly disposed on said other side of the flexible substrate.

15. The sensing panel according to any one of the preceding claims, wherein the flexible substrate is on one major surface provided with an attachment material (15) for removably attaching said sensing panel to an outer surface of an absorbent hygiene article.

16. The sensing panel according to any one of the preceding claims, comprising a receptacle (50) for a data logger unit (60), the data logger unit comprising a plurality of contact terminals (68) of a logger side terminal portion (61), adapted such that when the data logger unit (60) is engaged with said receptacle (50), said logger side terminal portion (61) is aligned to said panel side terminal portion (30) to establish contact between contact terminals (32) of the panel side terminal portion (30) and contact terminals (68) of the logger side terminal portion (61).

17. A hygiene monitoring device (1) comprising a sensing panel (10) as defined in any one of the preceding claims and a data logger unit (60), wherein the data logger unit (60) is, optionally removably, attached to said sensing panel (10) and electrically connected to the plurality of first sensing plates (21, ... , 27) and to the second sensing plate (28) and adapted to measure an impedance between each one of said first sensing plates and said second sensing plate.

18. A hygiene monitoring device according to claim 17, wherein said sensing panel (10) is adapted to be associated with a garment facing surface (101) of an absorbent hygiene article (100), the hygiene monitoring device (1) being adapted to assess a liquid content absorbed by said absorbent hygiene article, wherein said assessment is at least partly based on an impedance measured between each one of said first electrically conductive plates and said second electrically conductive plate.

19. A kit of parts for a hygiene monitoring device, comprising a sensing panel (10) as defined in any one of claims 1 to 16, and a data logger unit (60) adapted to be removably attached to said sensing panel and electrically connected to the plurality of first sensing plates (21 , ... , 27) and to the second sensing plate (28) and adapted to measure an impedance between each one of said first sensing plates and said second sensing plate.