Wearable absorbent article having a conductor array

Abstract

The present disclosure relates to a wearable absorbent article comprising at least one material layer and a conductor arrangement that is at least partially deposited, and optionally printed, on the material layer. The conductor arrangement is formed from a composition comprising dialcohol cellulose and a conductive material.

Description

Technical Field

[0001] The present disclosure relates to wearable absorbent articles, such as diapers, sanitary napkins, incontinence garments, or medical dressings such as wound dressings, including a conductor array.

[0002] The present disclosure also relates to a method of manufacturing a wearable absorbent article comprising a conductor array.

Background Art

[0003] Wearable absorbent articles, such as diapers, sanitary napkins, incontinence garments, medical dressings, and the like, are widely used both in the home and in facilities for purposes such as infant care, menstrual management, management of body exudates or effluents, and incontinence management. However, a known problem associated with the use of absorbent articles is that these articles have a finite absorption capacity with respect to absorption, and when the absorption capacity is exceeded, the absorbent article loses its effectiveness, for example, leaks occur or at least it can no longer absorb further.

[0004] Therefore, the user of such an article or their caregiver must predict that the absorbent article is approaching its absorption capacity and then take measures to replace the article before the absorption capacity is reached. In situations where there are many users of such absorbent articles and relatively few caregivers, such as in a facility, the management of the capacities of the various absorbent articles in use becomes a significant management burden.

[0005] It can be very difficult for the user or caregiver to accurately predict or determine the state of the absorbent article with respect to both the available absorption capacity and the necessary replacement of the article. Even if the absorbent material demand for the article is sufficiently predictable, it is necessary to record and experiment for a certain period of time before a pattern is established and an appropriate absorbent article can be provided.

[0006] Therefore, a system that can warn the user or caregiver that saturation of the absorbent article has occurred or is imminent would be beneficial. Such a system can take the form of a moisture sensor for detecting moisture within the absorbent article. The moisture sensor can detect moisture by using a conductor array provided within the wearable absorbent article and measuring the resistance between different conductors of the conductor array. In this way, the moisture sensor may be able to determine both the amount of moisture and the location where the moisture event has occurred within the absorbent article.

[0007] One approach to an absorbent article incorporating a moisture sensor is described in Patent Document 1. It may also be contemplated to include other sensors, such as an infection sensor, a hydration level sensor, etc., in the wearable absorbent article.

[0008] Adding a moisture sensor causes an increase in the cost of the absorbent article and also makes the manufacturing process more complex compared to absorbent articles without a moisture sensor.

Prior Art Documents

Patent Documents

[0009]

Patent Document 1

Patent Document 2

Non-Patent Documents

[0010]

Non-Patent Document 1

Non-Patent Document 2

Non-Patent Document 3

Non-Patent Document 4

Non-Patent Document 5

Summary of the Invention

Problems to be Solved by the Invention

[0011] Therefore, there is a need for an improved wearable absorbent article that eliminates at least one of the above-mentioned drawbacks.

Means for Solving the Problems

[0012] The above object aspect is achieved by the wearable absorbent article according to the present disclosure.

[0013] One aspect of the present disclosure relates to a wearable absorbent article including at least one material layer and a conductor arrangement at least partially deposited on the material layer. This conductor arrangement is formed from a composition containing dialcohol cellulose and a conductive material.

[0014] According to some embodiments, the conductor arrangement is at least partially printed on the material layer.

[0015] According to some embodiments, the conductor arrangement is completely deposited on a plurality of material layers including at least one material layer. The conductor arrangement can be completely deposited on at least one material layer.

[0016] According to some embodiments, the conductor array is printed entirely on a plurality of material layers including at least one material layer. The conductor array can be printed entirely on at least one material layer.

[0017] The composition deposited (e.g., printed) on at least one material layer or a plurality of material layers may be a conductive bioink containing modified cellulose fibers, where the cellulose has been partially converted to dialcohol cellulose and is hereinafter referred to as dialcohol-modified cellulose (DALC) fibers. DALC fibers have very high flexibility and ductility and can be melt-processed. Manufacturing the conductive arrangement of the absorbent article can potentially eliminate the energy-intensive process of preparing nanocellulose. Furthermore, the content of the necessary conductive material can be reduced without sacrificing conductivity.

[0018] The manufacture of the absorbent article can be cost-effective and environmentally friendly because the energy consumed in the manufacturing process can be less compared to manufacturing other absorbent articles including the conductive arrangement.

[0019] According to some embodiments, the conductor array includes a detection device or a part of a detection device. The detection device can be configured to include two elements and measure the resistance between the two elements. According to some embodiments, the detection device may be an impedance sensor.

[0020] For some embodiments, the detection device can be configured to detect one or more of infection, microbial growth, temperature, hydration level, etc. The detection device may be a moisture sensor or another type of sensor.

[0021] According to some embodiments, the wearable absorbent article includes a detection device or a part of a detection device that is in electrical contact with the conductor array. The detection device can be configured to include two elements and measure the resistance between the two elements. According to some embodiments, the detection device may be an impedance sensor.

[0022] The value of the impedance measured by the detection device can change (e.g., decrease) in response to the introduction of a liquid such as urine into a wearable absorbent article (e.g., a diaper or a feminine hygiene product). Therefore, the detection device can be used to detect the presence of a liquid such as urine in (a part of) the wearable absorbent article. When the detection device is configured to measure impedance, it can be deposited (printed) on at least one or a plurality of material layers so as not to require galvanic contact between the detection device and the liquid to detect the presence of the liquid. In other words, the liquid absorbed by the absorbent layer of the wearable absorbent article may be detected remotely.

[0023] When using an additional detection device positioned on the wearable absorbent article to be in electrical contact with a conductive arrangement provided thereon, the idea of detecting a liquid by a sensing element for measuring impedance enables a configuration where the detection device is positioned on the surface of the wearable absorbent article facing the clothing. The latter arrangement can then be associated with a reduction in the effort related to the application and / or removal of the detection device. Further, the attachment and / or removal can also be performed while a person such as an infant or a patient is wearing the wearable absorbent article.

[0024] According to some embodiments, the conductor arrangement includes an additional detection device or a part of the additional detection device. The additional detection device can be provided with two elements and configured to measure the resistance between the two elements. According to some embodiments, the additional detection device may be an impedance sensor.

[0025] According to some embodiments, the wearable absorbent article includes an additional detection device or a part of the additional detection device in electrical contact with the conductor arrangement. The additional detection device can be provided with two elements and configured to measure the resistance between the two elements. According to some embodiments, the additional detection device may be an impedance sensor.

[0026] The presence of an additional detection device can promote an improvement in measurement accuracy. That is, when an additional second detection device is provided in addition to this detection device, for example, impedance measurement can be possible at at least two parts of the wearable absorbent article. Therefore, even when the liquid is not introduced into the portion related to the arrangement of one of the detection devices, it may be possible to determine that there is liquid in the wearable absorbent article. Therefore, the possibility of receiving a "false negative" measurement result seems low.

[0027] Furthermore, the presence of a plurality of detection devices can make it possible to draw conclusions regarding the saturation of the wearable absorbent article.

[0028] According to some embodiments, the conductive arrangement is provided on the body-facing side of the wearable absorbent article. This can make it possible to detect the presence of a fluid by direct (galvanic) contact with the fluid.

[0029] According to some embodiments, the conductive arrangement is provided on the side of the wearable absorbent article facing the clothing. This can make it possible to indirectly detect the presence of a fluid, that is, without (galvanic) contact with the fluid.

[0030] The wearable absorbent article may be provided with one or more fluid absorption regions for absorbing fluids and a mounting position for mounting an electronic device or an electronic device. The conductor arrangement electrically connects the mounting position for mounting the electronic device or an electronic device to at least one detection position for detecting the moisture of at least one or two or more of the fluid absorption regions among the fluid absorption regions.

[0031] The electronic device may be the detection device described above. The electronic device may also be a device for transmitting a signal to an external device.

[0032] The conductor array may comprise a plurality of elongated conductors extending along an extending direction. Each of the conductors is electrically connected to a respective electrode, and the electrodes may be arranged and configured to contact a fluid absorption region of the wearable absorbent article.

[0033] The electronic device may be configured to detect moisture at one or more locations within the fluid absorption region by measuring the electrical resistance between two of the plurality of electrodes through the conductors.

[0034] At least some of the conductors may be different with respect to the cross-section and thus may have different electrical resistances.

[0035] The conductors have a length in the range of 1 cm to 60 cm in their respective extending directions and / or a cross-sectional area in the range of 0.01 mm 2 to 1.00 mm 2 in the range perpendicular to their respective extending directions.

[0036] The fluid absorption region includes an absorbent core, and at least a part of the conductor array may be arranged and configured to be electrically insulated from the absorbent core.

[0037] The electronic device may include a moisture detection unit that is removably attached to the remaining part of the wearable absorbent article or embedded in the remaining part of the wearable absorbent article.

[0038] The wearable absorbent article may be a diaper, a sanitary napkin, or incontinence clothing.

[0039] The wearable absorbent article may be a medical dressing such as a wound dressing. The medical dressing may include a wound contact layer, an absorbent core, and a backing layer.

[0040] According to some embodiments, the conductor array includes a ground electrode and a capacitor electrode, and the ground electrode may form a closed loop around the capacitor electrode.

[0041] The material layer may include at least one article selected from the group consisting of flexible materials such as non-woven fabrics, films, tissue papers, and textiles.

[0042] The conductor array may include from 5 wt% to 70 wt% of an electroactive material. The conductor array may include from 30 wt% to 95 wt% of dialcohol cellulose. The conductor array may include from 10 wt% to 80 wt% of a plasticizer.

[0043] As used herein, the term "plasticizer" generally refers to a substance or material incorporated into a matrix-forming material to enhance flexibility or processability. Many plasticizers tend to weaken the intermolecular forces between polymer chains, and as a result, can exhibit a plasticizing effect by improving flexibility and compressibility or causing discontinuities in the polymer matrix. Examples of some classes of plasticizers include sugars (monosaccharides, disaccharides, or oligosaccharides), alcohols, polyhydric alcohols, acids, salts, lipids and derivatives (fatty acids, monoglycerides, esters, phospholipids, etc.), and surfactants. Specific examples of suitable plasticizers include, but are not limited to, glucose, fructose, sorbitol, polyethylene glycol, glycerol, propylene glycol, lactitol, sodium lactate, hydrated hydrolyzed starch, trehalose, or honey, and combinations thereof. Other suitable plasticizers for use in the present disclosure include DMSO and ionic liquids.

[0044] The conductive material may include a conductive polymer. The conductive polymer may be PEDOT:PSS. "PEDOT:PSS" is a polymer compound, also called a polymer complex, that contains poly-3,4-ethylenedioxythiophene (PEDOT) and polystyrene sulfonic acid (PSS) in any ratio. PEDOT:PSS is available from multiple suppliers and is commonly used in conductive bioinks due to its ease of use. A PEDOT:PSS ratio of 1:2.5 can be used to form the conductive material, although it is generally understood that this ratio can be varied.

[0045] Conductive polymers such as PEDOT:PSS, as components used in the conductive arrangement configuration, can bring several advantages as they are electroactive components beneficial in terms of processability, electrochemical properties, and charge transfer ability. Such polymers may need to be doped with solvents such as ionic liquids, concentrated sulfuric acid, dimethyl sulfoxide (DMSO), etc. to increase the electron conductivity when applied to electronic devices. However, in the compositions used in the conductive arrangement configuration according to the present disclosure, the addition of organic solvents may not be required. This can be advantageous from the viewpoints of manufacturability, cost efficiency, and environmental considerations.

[0046] According to some embodiments, the conductor array has a conductivity of at least 0.05 S / cm. This can have a conductivity of at least 0.1 S / cm. This can have a conductivity of at least 0.5 S / cm. This can have a conductivity of at least 1 S / cm.

[0047] Dialcohol cellulose may include fibers having a diameter of at least 1 μm (and according to some embodiments, there are no fibers with a smaller diameter). According to some embodiments, dialcohol cellulose includes fibers having a diameter of at least 5 μm (and according to some embodiments, there are no fibers with a smaller diameter). Dialcohol cellulose may include fibers having a diameter of at least 8 μm (and according to some embodiments, there are no fibers with a smaller diameter). Dialcohol cellulose may include fibers having a diameter of at least 12 μm (and according to some embodiments, there are no fibers with a smaller diameter).

[0048] Dialcohol cellulose may include nanofibrils having a diameter of less than 1000 nm, optionally less than 500 nm, or less than 200 nm, or less than 100 nm, or less than 50 nm.

[0049] The plasticizer may include a polyhydric alcohol.

[0050] The polyhydric alcohol may be selected from the group consisting of glycerol, sorbitol, and erythritol.

[0051] The polyhydric alcohol may include glycerol.

[0052] The plasticizer may include DMSO.

[0053] The plasticizer may include an ionic liquid.

[0054] When the conductive arrangement includes a conductive polymer, the conductive polymer may include one or more polymers selected from the group consisting of polyphenylene, polypyrene, polyazulene, polynaphthalene, polyacetylene (PAC), poly-p-phenylene vinylene (PPV), polypyrrole (PPY), polyazepine, polyaniline (PANI), polythiophene (PT), poly-3,4-ethylenedioxythiophene (PEDOT), toluenesulfonyl (Tos), and polystyrene sulfonic acid (PSS).

[0055] The conductive arrangement may include 10 wt% to 50 wt% of the conductive polymer.

[0056] The conductive arrangement may include at least 40 wt% of the conductive polymer.

[0057] The conductive arrangement may include conductive carbon.

[0058] The conductive carbon may be selected from the group consisting of 1D carbon, 2D carbon, and 3D carbon. The 3D carbon may be graphite. The 2D carbon may be graphene. The 1D carbon may be a carbon nanotube.

[0059] The conductive arrangement may include a conductive 2D material. The conductive 2D material may be selected from the group consisting of graphene, MXenes, and molybdenum disulfide (MoS2).

[0060] Another aspect of the present disclosure relates to a method of manufacturing a wearable absorbent article. The method includes providing an absorbent article including at least one material layer, and depositing a composition including dialcohol cellulose and a conductive material on the at least one material layer to form a conductor arrangement on the at least one material layer.

[0061] According to some embodiments, the composition is deposited on the at least one material layer by any one or more of the techniques of 3D printing, 2D printing, screen printing, stencil printing, blade coating, melt processing molding, slot die coating, inkjet printing, laser printing, solution processing, vacuum filtration, solvent casting, and papermaking techniques.

[0062] The composition can be at least partially dried before, during, and / or after application of the composition.

[0063] The composition can be at least partially cured before, during, and / or after application of the composition.

[0064] The method can further include an additional step of adding a cross-linking agent before, during, and / or after application of the composition.

[0065] As used herein, the term "cross-linking agent" or "cross-linker" refers to a chemical substance capable of forming cross-linking chains between polymers, and further refers to an agent capable of providing cross-linking of polymer chains in the presence of a suitable reagent such as gamma-ray irradiation, or other types of electromagnetic radiation, or electron bombardment.

[0066] The cross-linking agent can be added before, during, and / or after application of the composition.

[0067] Another aspect of the present disclosure relates to an absorbent article manufactured by any of the aspects of the method according to the present disclosure.

[0068] Additional advantages and features of the present disclosure, which can be realized alone or in combination with one or more of the above-described features, will become apparent from the following description of specific embodiments, provided the features are not mutually inconsistent.

[0069] For a better understanding of the present disclosure and to show how it can be put into practice, reference will be made, by way of example only, to the accompanying drawings.

[0070] The description will be further made with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0071]

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Best Mode for Carrying Out the Invention

[0072] FIG. 1a is a top view showing a wearable absorbent article according to the present disclosure. This embodiment is a diaper 1.

[0073] The diaper 1 includes a main body 15, a first side portion 16, a second side portion 17, and an attachment member 7. The main body 15 is elongated in a first direction. The first direction is parallel to the longitudinal center line of the wearable absorbent article. The longitudinal center line extends from the front side 2 of the absorbent article facing the wearer's front side during use of the absorbent article to the back side 3 of the absorbent article facing the wearer's back side during use of the absorbent article.

[0074] The first side portion 16 and the second side portion 17 extend away from the main body 15 along a second direction perpendicular to the first direction. The first side portion 16 and the second side portion 17 extend away from the main body 15 on opposite sides of the main body 15. The attachment member 7 is disposed on both side portions 16, 17.

[0075] FIG. 1b is a cross-sectional view taken along the line A-A of FIG. 1a

[0076] The diaper 1 includes a liquid-permeable top layer 8 adapted to face the wearer during use and allow fluids such as urine or other body fluids to pass through, a liquid-impermeable bottom layer 9 facing the top layer 8 and adapted to prevent fluids from passing through, and an absorbent core 13 disposed between the bottom layer 9 and the top layer 8 for absorbing fluids.

[0077] The diaper 1 is configured to be worn around the user's waist by attaching the side portions 16, 17 to the main body 15 using the attachment member 7.

[0078] Furthermore, the diaper 1 includes a conductive arrangement 20 printed on the bottom layer 9.

[0079] Although the diaper has been described in relation to FIGS. 1a and 1b, the present disclosure also encompasses other embodiments of the wearable absorbent article with the conductor arrangement configuration according to the present disclosure. In particular, a conductor arrangement configuration similar or identical to that of FIGS. 1a and 1b can be printed on, for example, a medical dressing such as a wound dressing, or a sanitary napkin or incontinence garment.

[0080] FIG. 2a shows a conductive arrangement configuration 20 printed on a material layer of a first embodiment of a wearable absorbent article according to the present disclosure.

[0081] The conductive arrangement configuration can be printed, for example, on a diaper, a sanitary napkin, an incontinence garment, or a medical dressing. An example of a diaper will be described in more detail.

[0082] For example, the conductive arrangement configuration 20 can be printed on one of the layers of the diaper 1 of FIG. 1. Different embodiments are, for example, wound dressings on which the conductive arrangement configuration of FIG. 2a is printed on their layer.

[0083] The conductor array 20 is formed from a composition containing dialcohol cellulose and a conductive material and forms part of a detection device for detecting moisture in the diaper.

[0084] The conductor array 20 includes a plurality of elongated conductive wires and electrode wires, and each of the electrode wires is electrically connected to each of the conductive wires. The conductor array 20 is attached with a moisture detection unit (not shown), a control unit (not shown) for controlling the moisture detection unit, and a power source (not shown) 0 for supplying power to the control unit and the moisture detection unit.

[0085] The conductor array may further have a transmitter for transmitting information related to the moisture detected by the moisture detection unit or other related information. The conductor array may further have a receiver for receiving information such as instructions.

[0086] The conductor array comprises from 5 wt% to 70 wt% of an electrically active material, from 30 wt% to 95 wt% of dialcohol cellulose, and optionally from 10 wt% to 80 wt% of a plasticizer. The conductive material comprises a conductive polymer. The conductive polymer comprises poly-3,4-ethylenedioxythiophene and polystyrene sulfonic acid.

[0087] The conductive arrangement is printed on a material layer of the diaper 1 within the main part 15 of the diaper 1. This can be printed, for example, on the layer facing the absorbent core 13, the side facing the body, or the side facing the clothing, depending on the type of sensing technology used.

[0088] The power source can hold an energy storage part in the form of electrical energy and / or chemical energy. The power source can be any type of power source such as a battery, a cell, and / or a capacitor. For example, the power source can be a flexible paper battery / cell such as provided by Blue Spark Technologies, Inc. (located in Ohio, USA), Enfucell Oy (located in Finland), GS Nanotech (located in Korea), or Cymbet Corporation (located in Minnesota, USA).

[0089] The conductor array 20 has a conductivity of at least 0.05 S / cm, optionally at least 0.1 S / cm, or at least 0.5 S / cm, or at least 1 S / cm. The dialcohol cellulose comprises fibers having a diameter of at least 5 μm, such as at least 8 μm, such as at least 12 μm, such as at least 1 μm.

[0090] The conductor array 20 comprises a plurality of elongated conductors 4, and each conductor 4 extends along the same extending direction. The extending direction of the conductor 4 is parallel to the longitudinal center line of the wearable absorbent article (see, for example, the diaper 1 in FIG. 1). Each conductor 4 is printed on a material layer of the wearable absorbent article.

[0091] In the case of the embodiment of FIG. 2a, the conductive wires 4 have different lengths in the extending direction. The conductive wire 4 that is longer in the extending direction may have a lower electrical resistance per unit length compared to the conductive wire 4 that is shorter in the extending direction.

[0092] In particular, as schematically shown in the enlarged view of FIG. 2b, the longer conductive wire 4 has a cross-sectional area perpendicular to the extending direction that is wider compared to the cross-sectional area perpendicular to the extending direction of the shorter conductor 4. In this way, the resistance of the conductive wire 4 associated with the difference in length, that is, the difference in the overall or total resistance, can be reduced or eliminated in a particularly simple and efficient manner. However, for other embodiments, the conductive wires 4 having different lengths may have the same cross-section.

[0093] Furthermore, the conductive wire 4 having a longer length in the extending direction can be made of a material having a lower electrical resistance compared to the material from which the conductive wire 4 having a shorter length in the extending direction is made, such as a metal and / or a metal alloy, for example, a metal and / or a metal alloy.

[0094] The cross-sectional area and / or the material of the conductor 4 can be selected such that all of the conductors 4 have substantially the same electrical resistance.

[0095] As shown in FIG. 2a, each of the conductive wires 4 of the conductor array 20 is electrically connected to the electrode wire 6. In particular, each of the electrode wires 6 is electrically connected to the respective conductive wire 4 at the distal end of the conductive wire 4 in its extending direction, that is, at the end of the conductive wire 4 that is disposed further away from the moisture detection unit (not shown).

[0096] All of the electrode wires 6 extend along the same extending direction. The extending direction of the electrode wires 6 is substantially perpendicular to the extending direction of the conductive wires 4. All of the electrode wires 6 have substantially the same length in the extending direction.

[0097] The conductor 4 and the electrode 6 are disposed between the insulating substrate 24 and the insulating layer 25 such that the conductor 4 is covered by the insulating layer 25 and the electrode wire 6 is exposed through the opening 26. In this way, it can be reliably ensured that the conductor 4 is electrically insulated from the absorbent core of the wearable absorbent article, and the electrode 6 can be arranged and configured in a simple and efficient manner so as to contact the absorbent core. In this way, after a moisture event occurs in the absorbent core, an electrical contact is established between each one or a plurality of electrode wires of the electrode wire 6 and the absorbent core.

[0098] A moisture detector (not shown) is configured to detect moisture in one or more locations within the absorbent core by measuring the electrical resistance between adjacent electrode wires of the electrode wire 6 that pass through the conductor 4, i.e., the electrode wires 6 that are adjacent to each other. In particular, this electrical resistance is measured at the electrical contact 27 that is electrically connected to each conductor 4 at the proximal end of the conductor 4 in the extending direction of the conductor 4, i.e., at the end of the conductor 4 disposed close to the moisture detection unit (see FIGS. 2a and 2b). These electrical contacts 27 are arranged and configured adjacent to each other along the extending direction of the conductor 4, i.e., along the longitudinal center line of the wearable absorbent article.

[0099] For the embodiment of FIG. 2, the conductive arrangement 20 can be printed on the material layer of the diaper at a position such that the electrode wire 6 contacts the absorbent core of the diaper, but the conductor 4 is electrically insulated from the absorbent core by the insulating layer 25. After a moisture event occurs in the absorbent core, an electrical contact is established between each electrode wire of the electrode wire 6 and the absorbent core. In this way, the electrical contact is established between at least two electrode wires of the electrode wire 6 through the absorbent core.

[0100] A moisture detection unit (not shown) is configured to detect moisture at one or more positions within the absorbent core by measuring the electrical resistance between at least two of the electrode lines 6 passing through the conductive wire 4, for example, between adjacent electrode lines. The electrical resistance is measured at the electrical contact 27 (see FIGS. 2a and 2b) as detailed above.

[0101] FIG. 3a shows a conductive arrangement printed on a material layer of an embodiment of a wearable absorbent article according to the present disclosure. The conductive arrangement can be printed, for example, on a diaper, a sanitary napkin, incontinence clothing, or a medical bandage.

[0102] FIG. 3b shows a conductive arrangement printed on a material layer of an embodiment of a wearable absorbent article according to the present disclosure. The conductive arrangement can be printed, for example, on a diaper, a sanitary napkin, incontinence clothing, or a medical bandage.

[0103] The conductive arrangements shown in FIGS. 3a and 3b are configured to include the sensing element 10, and each shielding component 18 is provided continuously between each ground element (including each ground electrode line 12 and each ground line 20) and each signal line 14 so that there is no portion of the sensing element 10 where the shielding component 18 is not provided between the ground element and the signal line 14.

[0104] As described above, the conductive arrangement at least partially deposited on one or more material layers of a wearable absorbent article according to the present disclosure is formed from a composition containing dialcohol cellulose and a conductive material.

[0105] "Dialcohol cellulose" or "DALC" or "dialcohol-modified cellulose fiber" refers to modified cellulose obtainable by any method, as exemplified in Figures 4a and 5b, for example. This method involves oxidizing cellulose in a fiber suspension to dialdehyde cellulose and then reducing the dialdehyde cellulose to obtain dialcohol cellulose. Some of the methods for obtaining DALC are further described in Patent Document 2. This term also includes DALC nanofibrils, i.e., cellulose-based nanofibrils obtainable by microfluidization or mechanical treatment of DALC fibers. Although both cellulose nanofibrils and dialcohol-modified fibers can be referred to as dialcohol cellulose, it should be understood that nanofibrils can have a diameter of a few nanometers, such as less than 1000 nm, preferably less than 500 nm, or less than 200 nm, or less than 100 nm, or less than 50 nm, while the fibers are in the micrometer range and can have a diameter of at least 1 μm, such as at least 5 μm, at least 8 μm, at least 12 μm, etc., without limitation. The length of the fibers and nanofibrils can be in the range of micrometers or millimeters.

[0106] Generally, when referring to DALC cellulose, it is understood that a certain amount of cellulose has been modified. Typically, the desired modification depends on the application. However, generally, for the applications disclosed herein, a degree of modification or substitution of 10% to 50% is sufficient. However, lower or higher degrees of substitution or modification can also be used.

[0107] "PEDOT:PSS" is a polymeric compound, also called a polymer complex, which contains poly-3,4-ethylenedioxythiophene (PEDOT) and polystyrene sulfonic acid (PSS) in any ratio. PEDOT:PSS is available from multiple suppliers and can be used in conductive bioinks due to its ease of use. Unless otherwise noted, a PEDOT:PSS ratio of 1:2.5 is used, but the ratio can be changed and is generally understood to be within the scope of this disclosure.

[0108] DALC-based bioink The composition used to form a conductive arrangement deposited on a wearable absorbent article according to this disclosure may include dialcohol cellulose and an electroactive material. The dialcohol cellulose in this disclosure can take the form of DALC fibers or DALC nanofibrils. DALC fibers and nanofibrils can be prepared using methods known to those skilled in the art. For example, DALC fibers can be obtained by oxidizing cellulose in a fiber suspension to dialdehyde cellulose and then reducing the dialdehyde cellulose to obtain dialcohol cellulose. If necessary, DALC nanofibrils can then be obtained by microfluidization or mechanical treatment of DALC fibers.

[0109] This composition may further include a plasticizer.

[0110] The electroactive material in the bioink refers to any material that conducts current, such as a conductive material. In some embodiments, the composition includes from 5 wt% to 70 wt% of the electroactive material. In some embodiments, the composition includes from 10 wt% to 50 wt% of the electroactive material. In some embodiments, the composition includes 40 wt% of the electroactive material.

[0111] In some embodiments, the composition includes from 30 wt% to 95 wt% of dialcohol cellulose.

[0112] In some embodiments, the composition comprises from 10 wt% to 80 wt% of a plasticizer, such as from 15 wt% to 75 wt% of a plasticizer. Alternatively, the composition can comprise from 1 vol% to 10 vol% of a plasticizer.

[0113] The conductivity of the conductive arrangement can be about 0.1 S / cm. In some embodiments, the composition has a conductivity of at least 0.05 S / cm, such as at least 0.1 S / cm, such as at least 0.5 S / cm, such as at least 1 S / cm.

[0114] In some embodiments, the plasticizer comprises a polyhydric alcohol. Examples of polyhydric alcohol plasticizers include glycerol, sorbitol, and erythritol. In some embodiments, the plasticizer comprises glycerol. As illustrated in the examples, glycerol, when combined with DALC and PEDOT:PSS, enhanced the separation of PEDOT and PSS, thereby increasing the conductivity of the composition. The addition of glycerol also enabled the composition to retain the gel properties of the ink and enhanced the moisture stability and adhesion to the substrate of the ink. The moisture stability and the ability of the composition to retain moisture can extend the shelf life of devices based on the compositions of the present disclosure compared to conventional hydrogel materials.

[0115] In some embodiments, the plasticizer comprises DMSO.

[0116] In some embodiments, the plasticizer comprises an ionic liquid. The term "ionic liquid" is generally defined as a molten salt composed of ions and being liquid at a certain temperature.

[0117] In some embodiments of the present disclosure, the electroactive material includes a conductive polymer. It is understood that the term "conductive polymer" can include a mixture or complex of multiple polymers, which may or may not have conductivity on their own when the mixture exhibits conductivity. The conductive polymer can include, for example, one or more polymers selected from the group consisting of polyphenylene, polypyrene, polyazulene, polynaphthalene, polyacetylene (PAC), poly-p-phenylene vinylene (PPV), polypyrrole (PPY), polyazepine, polyaniline (PANI), polythiophene (PT), poly-3,4-ethylenedioxythiophene (PEDOT), toluenesulfonyl (Tos), and polystyrene sulfonic acid (PSS).

[0118] In some embodiments, the conductive polymer includes PEDOT:PSS.

[0119] In some embodiments, the composition includes from 5 wt% to 70 wt% of the conductive polymer.

[0120] In some embodiments, the composition includes from 10 wt% to 50 wt% of the conductive polymer.

[0121] In some embodiments, the composition includes 40 wt% of the conductive polymer.

[0122] In some embodiments, the electroactive material includes a conductive carbon material. The term "conductive carbon material" can include any carbon allotrope that conducts electricity. Based on the dimensional structure for electron confinement, the carbon can be classified as 0D, 1D, 2D, and 3D carbon. In some embodiments, the conductive carbon material is selected from the group consisting of 1D carbon, 2D carbon, and 3D carbon.

[0123] In some embodiments, the 3D carbon is graphite.

[0124] In some embodiments, the 2D carbon is graphene.

[0125] In some embodiments, the 1D carbon is a carbon nanotube.

[0126] In some embodiments, the electroactive material includes a conductive 2D material. The 2D material may be an organic or inorganic conductive material characterized by a 2D structure. In some embodiments, the conductive 2D material is selected from the group consisting of graphene, MXenes, and molybdenum disulfide (MoS2).

[0127] The following describes a method for manufacturing a composition used to form a conductive arrangement deposited on a wearable absorbent article according to the present disclosure. The method includes mixing dialcohol cellulose with an electroactive material, thereby obtaining a composition.

[0128] In some embodiments, the method for manufacturing the composition further includes a subsequent step in which a plasticizer is mixed with the dialcohol cellulose and the electroactive material.

[0129] Processing of Bioink The bioink can further be processed into a conductive material. Examples of processing techniques include, but are not limited to, extrusion, printing, or solution processing techniques.

[0130] In some embodiments, the composition is applied to the wearable absorbent article by 3D printing, 2D printing, screen printing, stencil printing, blade coating, melt processing, molding, slot die coating, inkjet printing, laser printing, solution processing, vacuum filtration, solvent casting, and / or papermaking techniques, thereby obtaining the conductive material.

[0131] In some embodiments, the composition is at least partially dried before, during, and / or after application of the composition.

[0132] In some embodiments, the composition is at least partially cured before, during, and / or after application of the composition.

[0133] A crosslinking agent can be added to the composition to make the composition a 3D network structure. In some embodiments, the composition further comprises a crosslinking agent. The crosslinking agent can be added before, during, and / or after application of the composition. In some embodiments, the crosslinking agent is selected from the group consisting of ionic crosslinking agents, photo-crosslinking agents, and covalent crosslinking agents.

[0134] In some embodiments, the conductive material has a conductivity ranging from 0.1 S / cm to 100 S / cm, such as 40 S / cm, such as 35 S / cm, such as 30 S / cm, from 0.05 S / cm to 150 S / cm. In some embodiments, the conductive material has a conductivity of at least 0.1 S / cm, such as at least 0.5 S / cm, such as at least 1 S / cm, at least 0.05 S / cm, preferably at least 0.1 S / cm. However, in certain embodiments, the conductivity can be 100 S / cm or even 150 S / cm.

[0135] Methods for manufacturing the conductive material to be used in the conductive arrangement according to the present disclosure can include steps of 3D printing, 2D printing, screen printing, stencil printing, blade coating, melt processing, molding, slot die coating, inkjet printing, laser printing, solution processing, vacuum filtration, solvent casting, and / or papermaking techniques.

[0136] In some embodiments, the method further comprises an additional step of adding a crosslinking agent before, during, and / or after application of the composition.

[0137] Use of DALC bioink-based materials Conductive materials can be used within sensors. Such sensors can be, for example, capacitive sensors that can be used in a number of ways. For example, the conductive material can be incorporated into the material such that a change in capacitance is detected when the properties of the material change. This can be, for example, the water content of the material, the size / dimensions of the material, and / or the deformation of the material. In other embodiments, the change in capacitance can be detected by an external object such as a hand or finger touching the sensor and causing a change in capacitance.

[0138] Some embodiments for using a conductive material in an electrode.

[0139] Conductive materials can be used in automotive devices.

[0140] (Example) (Example 1) Preparation and evaluation of DALC-based conductive ink Materials and methods Materials PEDOT:PSS (Clevios™ PH 1000, 1.3 wt%) manufactured by Heraeus. Glycerol, sodium periodate, sodium borohydride, polyvinyl alcohol (PVA), and sulfuric acid were all purchased from Sigma Aldrich. All chemicals were used without further purification.

[0141] Next, the dialcohol-modified cellulose fiber was prepared according to the method reported previously (Non-Patent Document 1). Briefly, bleached softwood kraft fiber (defibrinated, fiber concentration 15 g / L) was oxidized to dialdehyde cellulose using sodium periodate (1.35 g per 1 g of fiber). This reaction proceeded at room temperature in the dark for 37 hours, and the pulp was thoroughly washed after completion of the reaction. Hydroxylamine titration was used to determine the aldehyde content. The dialdehyde fiber was reduced to dialcohol cellulose fiber by adding sodium borohydride (0.4 g per 1 g of fiber), and the reaction was carried out in 0.01 M phosphate buffer for 3 hours. Thereafter, the fiber was thoroughly washed and stored at 4 °C until further use. To prepare dialcohol-modified cellulose nanofibril, the dialcohol-modified cellulose fiber was microfluidized.

[0142] Preparation of DALC-based ink without plasticizer To prepare DALC-based conductive ink, dialcohol-modified cellulose fiber (degree of modification or substitution 10% - 50%) or dialcohol-modified cellulose nanofibril (degree of modification 10% - 50%) was mixed with PEDOT:PSS at different weight ratios, where the dialcohol-modified cellulose (fiber or nanofibril) was composed of at least 30 wt%, preferably 30 to 95 wt% of the total composition of the ink, and PEDOT:PSS was composed of at least 5 wt%, preferably 5 to 70 wt% of the total composition of the ink.

[0143] Preparation of DALC-based ink with plasticizer To prepare the ink, dialcohol-modified cellulose fibers (degree of modification or substitution 10% - 50%) or dialcohol-modified cellulose nanofibrils (degree of modification 10% - 50%) and PEDOT:PSS are mixed at different dry weight ratios, where the dialcohol-modified cellulose (fibers or nanofibrils) is composed of at least 30 wt%, preferably 30 wt% to 95 wt% of the total composition of the ink, and PEDOT:PSS is composed of at least 5 wt%, preferably 5 wt% to 70 wt% of the total composition of the ink. The workflow of the said preparation is shown in Figure 4b. Also, all inks contained a plasticizer (corresponding to about 10 wt% to 80 wt% of the total composition) comprising 1 vol% to 10 vol% of the total composition. 1 vol%, 5 vol%, and 10 vol% of glycerol were used in the preparation of the ink. The ink was placed in the draft, thereby evaporating the moisture to achieve the desired solid content.

[0144] Rheology measurement A DHR-2 rheometer (TA Instruments, located in Newcastle, Delaware, USA) with a 25 mm parallel plate geometry (gap distance 1 mm) was used to measure the rheological properties of the ink. All measurements were performed at 25 °C. Each sample was equilibrated for 10 minutes before analysis. The reported values are the average of three repeated measurements. To characterize the linear viscoelastic and flow properties of the ink, flow analysis was performed for inks with different PEDOT:PSS wt% as shown in Figure 2d, and also at different solid contents as shown in Figures 2a and 2c, in the range of 0.01 to 500 s -1 of. Time sweep measurements were performed to estimate the storage modulus (black line) and loss modulus (white line), and the results are shown in Figure 5b.

[0145] SEM and EDS measurements A Hitachi S-4800 field emission scanning electron microscope (SEM) equipped with an energy-dispersive X-ray spectroscopy (EDS) detector was used to study the morphology and elemental mapping. Images (A) and (B) in Figure 7 were obtained using this apparatus.

[0146] Wide-angle X-ray scattering (WAXS) A known technique for determining the crystallinity of polymers such as PEDOT is the wide-angle X-ray scattering method (WAXS). Wide-angle X-ray scattering measurements were performed using an Anton Paar SAXSpoint 2.0 system (Anton Paar, Graz, Austria) equipped with a Microsource X-ray source (Cu Kα radiation with a wavelength of 0.15418 nm) and a Dectris 2D CMOS Eiger R 1M detector. The sample-detector distance was 111 mm. The samples were mounted on a solid sample holder (Anton Paar, Graz, Austria), which was mounted on a VarioStage (Anton Paar, Graz, Austria). The samples were placed under vacuum. For each sample, three frames with a duration of 20 minutes were read out from the detector. The data obtained using this apparatus are shown in FIGS. 8a and 8b.

[0147] Measurement of contact angle A contact angle meter (Theta lite, Biolin Scientific) was used to determine the contact angle on the samples as shown in images (A) and (B) of FIG. 9.

[0148] Results Preparation of DALC-based inks As can be understood herein, it has been shown that DALC-modified cellulose can be used as a bio-based alternative to typical polymers of printable conductive inks. The reason is not fully understood, but some similarities with, for example, PVA can be found. For example, dialcohol-modified fibers have abundant polar hydroxyl groups available on the surface. PVA has previously been known to form an interpenetrating network structure with PEDOT:PSS, resulting in the formation of a tough, stretchable, and flexible hydrogel that can be used, for example, in energy storage devices.

[0149] The ink prepared without a plasticizer showed good processability but had low conductivity. Also, the final material had no moisture stability. Therefore, the plasticizer also helped to increase the conductivity of PEDOT:PSS and impart moisture stability to the DALC / PEDOT:PSS composite material (the reason for this is not fully understood).

[0150] Figures 5a, 5b, 5c, and 5d show the rheological analysis of DALC / PEDOT:PSS inks at different PEDOT:PSS wt% (20 wt%, 40 wt%, and 70 wt%), and further the rheological analysis of inks (PEDOT:PSS = 40 wt%) at different solid content contents (3 - 10 wt%). Inks with a solid content content of 6 - 10% showed clear shear thinning and shear yield behavior, i.e., the requirements of inks typically required for printing. Inks with a low solid content content (1 - 5%) are usually required for printing techniques such as blade coating, stencil printing, screen printing, slot die coating, or solution processing. Inks with a solid content content of 6 - 8 wt% were used for 3D printing in subsequent examples.

[0151] The inks showed gel-like behavior at solid content contents higher than 3 wt%. Atomic force microscope (AFM) images of the dried samples showed that the PEDOT:PSS particles were organized in a pearl necklace-like morphology on the DALC surface, as shown in Figure 3. Therefore, this can form an intertwined network structure of fibers covered with PEDOT:PSS, resulting in gel-like properties.

[0152] Interaction between DALC fibers and PEDOT:PSS To evaluate the distribution of PEDOT:PSS in the DALC / PEDOT:PSS composite, scanning electron microscope (SEM) images and sulfur mapping images of the 3D printed samples were collected. As shown in Figures 7a and 7b, these show that the surface and the cross-section of the layer are covered with PEDOT:PSS particles, and the individual fibers cannot be identified because the DALC fibers have film-forming properties. Therefore, due to the excellent film-forming properties of the DALC fibers, good conductivity can be achieved by the uniform adsorption of PEDOT:PSS particles on both the outer and inner surfaces of the fibers.

[0153] An important factor for good conductivity is to remove the free PSS from PEDOT:PSS, thereby better filling the PEDOT crystallites. As shown in Figures 8a and 8b, WAXS shows a strong PSS peak (d-spacing from 0.51 nm to 0.44 nm) shifting from 1.3 Å in pure PEDOT:PSS to 1.4 Å in the 3D printed film, which indicates a decrease in the stacking distance between the PSS crystallites. However, the PEDOT 010 and PEDOT 100 peaks involved in the π-π stacking of the PEDOT crystallites have disappeared (Figure 5a). On the other hand, after washing the 3D printed film with water, these PEDOT peaks appeared, and furthermore, the intensity of the accompanying PSS peak decreased significantly (Figure 8b). Additionally, the PEDOT 010 peak, which is typically assigned to the edge-on orientation of the PEDOT crystallites, shifted from a q-value of 1.73 Å in pure PEDOT:PSS to 1.82 Å in the 3D printed sample. -1 to 1.4 Å in the 3D printed film. -1 This indicates a decrease in the stacking distance between the PSS crystallites. However, the PEDOT 010 and PEDOT 100 peaks involved in the π-π stacking of the PEDOT crystallites have disappeared (Figure 5a). On the other hand, after washing the 3D printed film with water, these PEDOT peaks appeared, and furthermore, the intensity of the accompanying PSS peak decreased significantly (Figure 8b). Additionally, the PEDOT 010 peak, which is typically assigned to the edge-on orientation of the PEDOT crystallites, shifted from a q-value of 1.73 Å in pure PEDOT:PSS to 1.82 Å in the 3D printed sample. -1 from a q-value of 1.73 Å in pure PEDOT:PSS to 1.82 Å in the 3D printed sample. -1Shifted to , resulting in a decrease in the stacking distance (from 0.36 nm to 0.34 nm). However, only a very weak PEDOT 100 peak indicating the face-on orientation of PEDOT crystallites appeared in the 3D printed film. Therefore, based on WAXS, it can be suggested that DALC fibers not only act as a template for PEDOT:PSS particles but also induce the PSS phase separation necessary for the increase in conductivity in PEDOT:PSS (Non-Patent Document 2). In addition, it has been shown to contribute favorably to the closest packing of PEDOT crystallites in the edge-on orientation, which is involved in the high conductivity of PEDOT:PSS. Analysis of morphology and X-ray scattering showed that DALC fibers induce crystallization in PEDOT:PSS similar to that of ethylene glycol or other secondary dopants.

[0154] Contact angle measurements of the printed DALC / PEDOT:PSS films, as shown in FIGS. 9a and 9b, showed an increase in the contact angle from 18 degrees as the printed and dried films to 121 degrees after washing these films. This indicates that the surface changed from hydrophilic to hydrophobic due to the enrichment in PEDOT. On the other hand, in pure PEDOT:PSS / glycerol films, the contact angle changed from 14.5 degrees to 38 degrees, which is not actually very significant. This implies that the surface was concentrated by more PEDOT domains (since PEDOT is highly hydrophobic) and PSS was removed after washing. This effect is evident in the DALC / PEDOT:PSS / glycerol samples compared to the pure PEDOT:PSS / glycerol samples. Therefore, dialcohol cellulose is important in inducing a greater phase separation of PEDOT:PSS.

[0155] In other words, the dialcohol-modified cellulose fibers showing moisture stability and the conductive ink based on PEDOT:PSS were produced. The DALC fibers act as a template for PEDOT:PSS particles, assist in the phase separation of PSS and PEDOT, and result in high conductivity of the printed ink even with a low content of PEDOT:PSS. Also, the use of modified cellulose fibers eliminates the need for cellulose nanofibrils with higher embedding energy, which are often used in bio-based electronics.

[0156] (Example 2) Ink processing and electrical characterization A direct ink writing 3D bioprinter was used to print various 2D and 3D patterns as shown in FIGS. 10a - 10d. Although a 3D bioprinter was used, the ink can also be printed with other printing technologies. These can also be processed using melt extrusion, solution processing techniques, and even papermaking techniques.

[0157] Materials and methods An Inkredible 3D bio - printer (Cellink®) was used for printing. After the ink was transferred to a syringe, centrifugation was performed for 30 seconds to remove the air bubbles that entered during mixing, and the ink was printed with a high - precision conical nozzle (20G, 25G, 27G, Cellink®). The print head speed and print pressure were manually adjusted for each ink composition. The printed samples were dried in an oven at a temperature of 60 °C overnight.

[0158] Electrical and electrochemical measurements A two - probe conductivity test was performed using a Keithley 2410 source meter. The samples were cut into rectangles with dimensions of 2 cm×0.5 cm×(thickness), and the voltage was recorded at a constant current. The resistance was calculated from the slope of the I - V curve. The following equation was used to calculate the conductivity. ρ=(R×w×t) / L σ=1 / ρ where ρ is the resistivity, R is the resistance of the sample, w is the width, t is the thickness, L is the distance between the two electrodes, and σ is the conductivity.

[0159] Cyclic voltammetry and galvanostatic charge-discharge measurements were performed in a three-electrode setup using a BioLogic VSP potentiostat. The setup consisted of a Ag / AgCl (BASi®, 3M NaCl) reference electrode, a platinum counter electrode, and a 3D-printed sample mounted on a platinum wire as the working electrode, immersed in 1M sulfuric acid as the electrolyte. The open circuit potential was recorded before the start of each measurement. The specific capacitance of the material was calculated from the discharge cycles using the formula: C=(I t) / (mΔV) It is calculated as where I is the discharge current, t is the discharge time, ΔV is the voltage window, and m is the mass of PEDOT in the sample.

[0160] The mass of PEDOT in the measured sample was calculated as follows: A rectangular piece (20 mm x 5 mm) of the 3D printed DALC / PEDOT:PSS sample was weighed (M0) and then soaked in 1M H2SO4 overnight, followed by thorough washing with Milli-Q water. The sample was left to dry under ambient conditions, and the mass of the dried sample was measured again (Mf). Since the sample had lost glycerol and some of the PSS present in the sample (residual electrolyte became clear after soaking the sample), the final weight consisted of only cellulose fibers and PEDOT:PSS. Mass of cellulose and PEDOT:PSS in the printed sample = Mf Mass of PEDOT:PSS in sample = 0.4*Mf, calculated based on the initial ratio of ink (DALC / PEDOT:PSS) Mass of PEDOT in sample = 1 / 3.5*(0.4*Mf), since the original ratio of PEDOT:PSS (as purchased) is 1:2.5 (ignoring loss of PSS)

[0161] result The 3D printed gel had a conductivity of 30±3 S / cm. As shown in Figure 11, the conductivity increased with the PEDOT:PSS content and leveled off at a PEDOT:PSS content of 40 wt%. This indicates the saturation threshold in the 3D printed samples, and even at a PEDOT:PSS content of 20 wt%, the conductivity was approximately 10 S / cm, which is sufficiently good for applications in bioelectronics. To the best of our knowledge, this is the first example of such good conductivity obtained for a 3D printed cellulose fiber-based PEDOT:PSS ink where the conductive material only occupies 20% of the total mass. Furthermore, as can be seen in Figure 12, the printed material was stable in water and physiological saline for at least 75 days without significant loss of conductivity. The rapid decrease in conductivity in PBS compared to water may be due to the dedoping of PEDOT:PSS in saline. The 3D printed pattern was foldable and stretchable, and the conductivity was maintained at 99%, as shown by the fact that the LED light continued to shine even after stretching the printed serpentine pattern (Figures 13a and 13b).

[0162] Electrochemical performance To demonstrate the potential of the developed 3D printable conductive ink for energy storage applications, the electrochemical performance was analyzed using a three-electrode device (Figure 14). Cyclic voltammetry (CV) for the material containing 40 wt% PEDOT:PSS showed an ideal supercapacitor behavior, i.e., a typical reaction from an electric double layer capacitor, maintaining a shape close to rectangular even at a high scan rate of 100 mV / s (Figure 15). The galvanostatic charge-discharge (GCD) curves were triangular in shape without significant voltage drops (Figure 16), indicating an efficient charge storage capacity due to the high conductivity of the printed working electrode. The gravimetric discharge capacity was as high as 197 F / g (normalized by the mass of PEDOT), and the areal capacity was 170 mF / cm even at 10 A / g 2It is (Fig. 17). The capacitances normalized with respect to the mass of the entire electrode are listed in Table 1. As can be seen from the figure, the 3D printed samples approach the theoretical specific capacitance of 210 F / g for PEDOT (Non-Patent Document 3), even though only 40% of the 3D printable ink is PEDOT:PSS. The specific capacitance at a current density of 1 A / g increases from 26 F / g to 211 F / g when the PEDOT:PSS content increases from 20 wt% to 40 wt%, but then decreases to 158 F / g when the PEDOT:PSS content further increases to 70 wt% (Table 2), i.e., it follows the same trend as the conductivity values. Again, this shows that a good conductive network structure is formed even with a low PEDOT:PSS content.

[0163] The kinetics of ion transport and charge transfer were studied using electrochemical impedance spectroscopy (EIS) in the frequency range from 10 MHz to 1 MHz. Before starting the charge / discharge cycle operation, the Nyquist plot (Fig. 18) shows a small intercept (0.7 Ω×cm 2 ) on the real impedance axis in the high-frequency region, indicating that the printed electrodes have a very low intrinsic resistance. The semicircle in the range from high frequency to medium frequency indicates the charge transfer resistance. The semicircle disappears after 10,000 charge / discharge cycles, indicating that the charge transfer at the electrode / electrolyte interface is improved during the cycle operation. Also, due to this good charge transfer, an increase in capacitance (from 230 to 280 F / g) was observed after 10,000 cycles (Fig. 19).

[0164] Table 1. Specific capacitance and current density values calculated by considering different active mass components [Table 1]

[0165] Table 2. Specific capacitance values for 3D printed samples with different PEDOT:PSS contents at 1 A / g

Table 2

[0166] Conclusion The 3D-printed samples show electrochemical performance equivalent to that of the latest bio-based PEDOT:PSS supercapacitors that use secondary doping such as acid treatment to dope either PEDOT:PSS or a mixture of PEDOT:PSS and other redox-active molecules.

[0167] The tail part of the vertical axis of the Nyquist plot (Figure 18) within the low-frequency range suggests that the diffusion resistance of the electrode is very low due to the benefits of the gel-like electrode structure.

[0168] (Example 3) Wearable Bioelectronic Device Materials and Methods For electrical and electrochemical measurements, refer to the materials and methods of Example 2.

[0169] EC-12 Test and ECG and EMG Measurements The EC-12 test was performed in a gel-gel configuration using the SEAM ECG Electrode Test Platform (QC Integrated, Ontario, Canada) at Beneli AB, Sweden.

[0170] To perform an ECG recording, a reference electrode was attached to the subject's abdomen, and then one of the electrodes (either gel or printed PEDOT) was attached to each of the subject's index fingers. To record the activity generated by opening and closing the hand, a reference electrode was attached to the elbow and two printed PEDOT electrodes were attached to opposite sides of the forearm. The signal generated by a hand sign was recorded using the same configuration by adding a third electrode between the other two electrodes. The electrical signals were registered using an RHD2132 amplifier (INTAN Technologies, located in the United States) on a custom PCB board. The output of the amplifier was connected to an integrated module housing a Spartan-6 FPGA (model XEM6010-LX45, Opal Kelly Inc., located in the United States), from which the RHX data acquisition software (INTAN Technologies, located in the United States) was used to collect the data via a USB connection by a laptop computer. The signals were recorded at a speed of 20 kS / s using different frequency ranges in each case, i.e., 1 to 100 Hz for ECG and 0.1 to 1 kHz for EMG. The acquired digital signals were processed offline with the help of the Python programming language.

[0171] Power line interference on the signal was removed by applying a second-order IIR digital filter having cutoff frequencies of 50, 100, 150, 200, 300, and 400 Hz. Fourth-order high-pass and low-pass Butterworth filters were applied at 1 kHz and 1 Hz, respectively, to limit the signal to the desired frequency band. The P-QRS-T complex on the ECG signal was detected as a 1-second window around peaks having a height greater than five times the standard deviation of the signal. For hand-signed EMG monitoring, first, signals from all three electrodes were combined to detect an event window. The combined signal was squared, smoothed using a moving average with a window of 1000 samples, and normalized. A 1-sample difference was calculated on the smoothed and normalized signal. A threshold of 0.07 was used for the difference to distinguish event windows with EMG activity from the background. On each event window, the power of the signal of each electrode was calculated and normalized by the power of the added signal.

[0172] Results Due to the stretchability, flexibility, and good electrochemical behavior of the 3D printed electrodes, it was possible to fabricate a supercapacitor device by twisting two extruded filaments coated with a gel electrolyte (Figure 20). This two-electrode device showed a discharge capacitance of 123 F / g and good cyclability of 3 A / g (Figure 21), indicating the potential for extruded fibers to be woven as a fabric for wearable energy storage devices.

[0173] Furthermore, to evaluate the potential of 3D printed electrodes in electrocardiogram (ECG) monitoring, a standard test (ANSI:AAMI EC12:2000) for disposable ECG electrodes in an electrode-electrode configuration was performed. Different parameters measured for three different PEDOT:PSS contents are summarized in Tble 3a (Table 3a) and Table 3b (Table 3b). In addition to established parameters such as AC impedance, DC offset voltage, and noise, defibrillation discharges were also measured, which determine the ability of the electrode to measure the ECG after a defibrillation event.

[0174] As can be seen from Table 3 (Table 3), even in the case of as little as 20 wt% of PEDOT:PSS, the AC impedance, noise level, and defibrillation discharge had values better than those recommended by the standard. To further test and demonstrate the applicability of the materials in the ECG monitoring device, 3D printed electrodes were tested for recording ECG signals. The standard three-lead ECG showed good ECG signals with distinct P-QRS peaks (Figures 22a and 22b).

[0175] Table 3a: EC-12 Test Results for 3D Printed Electrodes [Table 3]

[0176] Table 3b: EC-12 Test Results for 3D Printed Electrodes [Table 4]

[0177] Non-Patent Document 4 refers to Tsukada, Y. T. et al., "Validation of wearable textile electrodes for ECG monitoring.", Heart Vessels 34, pp. 1203-1211 (2019).

[0178] Non-Patent Document 5 refers to Tsukada, s., Nakashima, H. & Toimitus, K., "Conductive Polymer Combined Silk Fiber Bundle for Bioeletrical Signal Recording.", PLOS ONE 7, e33689 (2012).

[0179] Conclusion Conductive polymer inks have shown good electrochemical performance in energy storage and even in biopotential monitoring devices. This research opens the way to the processing of more environmentally friendly bioelectronics products by using bio-based high-performance conductive inks, making it possible to take a step towards environmentally friendly devices. Therefore, by reducing the need for cellulose nanofibrils, a low weight fraction of conductive polymer in 3D inks, and having good processability and excellent properties, scalable manufacturing of fiber-based wearable electronics products can be carried out at affordable prices.

[0180] (Example 4) Printed microelectrode array (MEA) device The inks developed herein can be used to measure and monitor the potentials of different types of cells such as cardiomyocytes and neurons. These are less expensive than commercially available gold-based MEAs and do not require patterning techniques for the cleanroom processing of such devices. Therefore, the time and cost associated with the processing of MEAs are saved.

[0181] It will be apparent to those skilled in the art that various modifications and changes can be made to the disclosed devices and systems without departing from the scope of the disclosure. Other aspects of the present disclosure will be apparent to those skilled in the art by considering the practice of the specification and features disclosed herein. The specification and examples are intended to be considered merely as examples. It is understood that many additional variations, modifications, and forms are possible and fall within the scope of the framework of the present disclosure.

Description of the symbols

[0182] 0 Power supply 1 Diaper 4 Elongated wire 6 Electrode 7 Mounting member 8 Top layer 9 Bottom layer 10 Sensing element 12 Ground electrode wire 13 Absorbent core 14 Signal wire 15 Main part 16 First side part 17 Second side part 18 Shield component 20 Conductive arrangement configuration, conductor array 20 Ground wire 24 Insulating substrate 25 Insulating layer 26 Opening 27 Electrical contact

Claims

**Claim 1** At least one material layer, A conductor array that is at least partially deposited on and optionally printed on the material layer, A wearable absorbent article comprising: The wearable absorbent article, wherein the conductor array is formed from a composition comprising dialcohol cellulose and a conductive material. **Claim 2** The conductor array includes a detection device or a part of a detection device, or The wearable absorbent article according to claim 1, wherein the wearable absorbent article includes a detection device or a part of a detection device that is in electrical contact with the conductor array. **Claim 3** The detection device includes two elements and is configured to measure the resistance between the two elements, or The wearable absorbent article according to claim 2, wherein the detection device is an impedance sensor. **Claim 4** The wearable absorbent article A fluid absorption region for absorbing fluid, An electronic device or a mounting position for mounting the electronic device, Comprising: The wearable absorbent article according to any one of claims 1 to 3, wherein the conductor array electrically connects the electronic device or the mounting position for mounting the electronic device to at least one detection position for detecting moisture in the fluid absorption region. **Claim 5** The fluid absorption region includes an absorbent core, The wearable absorbent article according to claim 4, wherein at least a part of the conductor array is arranged to be electrically insulated from the absorbent core. **Claim 6** The electronic device includes a moisture detection unit, The wearable absorbent article according to claim 4 or 5, wherein the moisture detection unit is removably attached to the remaining part of the wearable absorbent article or is embedded in the remaining part of the wearable absorbent article. **Claim 7** The wearable absorbent article according to any one of claims 1 to 6, wherein the wearable absorbent article is a diaper, a sanitary napkin, incontinence clothing, or a medical dressing optionally including a wound contact layer, an absorbent core, and a backing layer. **Claim 8** The conductor array includes a ground electrode and a capacitor electrode, The wearable absorbent article according to any one of claims 1 to 7, wherein the ground electrode forms a closed loop around the capacitor electrode. **Claim 9** The wearable absorbent article according to any one of claims 1 to 8, wherein the material layer includes at least one article selected from the group consisting of flexible materials such as non-woven fabric, film, tissue paper, and fabric.

10. The wearable absorbent article according to any one of claims 1 to 9, wherein the conductor array includes 5 wt% to 70 wt% of an electroactive material, 30 wt% to 95 wt% of the dialcohol cellulose, and optionally 10 wt% to 80 wt% of a plasticizer.

11. The conductive material includes a conductive polymer, Optionally, the wearable absorbent article according to any one of claims 1 to 10, wherein the conductive polymer includes poly-3,4-ethylenedioxythiophene and polystyrene sulfonic acid.

12. The wearable absorbent article according to any one of claims 1 to 11, wherein the conductor array has a conductivity of at least 0.05 S / cm, optionally at least 0.1 S / cm, at least 0.5 S / cm, or at least 1 S / cm.

13. The wearable absorbent article according to any one of claims 1 to 12, wherein the dialcohol cellulose includes fibers having a diameter of at least 1 μm, such as a diameter of at least 5 μm, at least 8 μm, or at least 12 μm.

14. A method for manufacturing a wearable absorbent article, comprising: - preparing an absorbent article including at least one material layer; - forming a conductor array on at least one of the material layers by depositing a composition including dialcohol cellulose and a conductive material on the at least one material layer. The method is provided with.

15. The composition is deposited on the at least one material layer by any one or more of the techniques of 3D printing, 2D printing, screen printing, stencil printing, blade coating, melt processing molding, slot die coating, inkjet printing, laser printing, solution processing, vacuum filtration, solvent casting, and papermaking techniques. Optionally, the composition is at least partially dried and / or cured before, during, and / or after applying the composition. The method according to claim 14.

16. ​ The method according to claim 14 or 15, further comprising the additional step of adding a crosslinking agent before, during, and / or after applying the composition. **Claim 17** The method according to any one of claims 14 to 16, wherein the crosslinking agent is added before, during, and / or after applying the composition. **Claim 18** An absorbent article manufactured according to the method according to any one of claims 14 to 17.

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