A wearable twelve-lead ECG monitoring clothes with one-way moisture conducting performance and a preparation method thereof

Abstract

The application discloses a wearable twelve-lead electrocardio monitoring clothes with one-way wet conductive performance and a preparation method thereof. A surface cross-linked hydrophilic polymer network captures liquid water through hydrophilic groups to generate radial swelling to lock water and eliminate streaming potential. A specific three-dimensional spatial conformation of a spiral crimped fiber provides an attachment carrier with different shapes and continuous gap channels for the cross-linked polymer network, avoids disordered accumulation of the polymer on the fiber surface, ensures effective coating and mechanical constraint of the rigid network on the substrate, inhibits pore channel blockage and mechanical performance degradation caused by hydrogel phase plastic slip, ensures morphological stability of the electrode structure under a wet state and persistent play of the wet conductive function while absorbing and locking interface sweat to eliminate streaming potential, fundamentally solves signal distortion problems caused by sweat accumulation and fit degradation, and realizes signal stability under high-precision long-term continuous monitoring.

Description

Technical Field

[0001] This invention relates to the field of biosensor technology, and more particularly to a wearable 12-lead electrocardiogram monitoring garment with unidirectional moisture-wicking properties and its preparation method. Background Technology

[0002] Cardiovascular disease, a prevalent chronic disease globally, presents an urgent need for long-term dynamic electrocardiogram (ECG) monitoring due to its insidious onset. Traditional monitoring devices are bulky and restrictive, making them unsuitable for routine out-of-hospital monitoring. With the development of wearable medical technology, 12-lead ECG monitoring garments, offering medical diagnostic-grade accuracy and capable of comprehensively capturing abnormal signals such as myocardial ischemia and arrhythmias, have become core devices for early screening and management of cardiovascular diseases, with a market size experiencing a compound annual growth rate of 24.9%.

[0003] However, existing ECG monitoring garments still face key technological bottlenecks: On the one hand, the instability of the skin-electrode interface caused by sweating is a prominent issue. Sweat easily causes electrode detachment and signal distortion, severely affecting monitoring accuracy. Most products lack efficient moisture management capabilities, and sweat accumulation leads to decreased wearing comfort, making it difficult to support long-term continuous monitoring, especially in sports or high-temperature environments. Although some products adopt waterproof designs or flexible electrode optimizations, they have not fundamentally solved the problem of synergistic effects between directional sweat conduction and signal stability, and also suffer from defects such as insufficient biocompatibility and strong wearing restriction.

[0004] Currently, no technology has deeply integrated unidirectional moisture-wicking functionality with a 12-lead ECG monitoring system. Existing products struggle to balance moisture management efficiency, signal acquisition accuracy, and wearability comfort. Therefore, developing a 12-lead ECG monitoring garment with unidirectional moisture-wicking capabilities that enables long-term stable monitoring, addressing industry challenges such as sweat interference and discomfort, is of great significance for promoting the clinical translation and widespread application of wearable ECG monitoring technology. Summary of the Invention

[0005] This invention overcomes the shortcomings of the prior art and provides a wearable 12-lead ECG monitoring garment with unidirectional moisture-wicking properties and its preparation method, aiming to solve the problems of sweat accumulation and unstable monitoring in existing monitoring garments.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: a method for preparing a wearable 12-lead ECG monitoring garment with unidirectional moisture-wicking properties, comprising the following steps:

[0007] S1. Twist and set polyester fibers to obtain spiral crimped fibers; prepare a coating solution by mixing hydrophilic polymer, crosslinking agent and water; immerse the spiral crimped fibers in the coating solution; and obtain super absorbent warp yarns after drying and thermal crosslinking treatment.

[0008] S2. Multi-layer fabrics are prepared using a three-dimensional orthogonal weaving process with super absorbent warp yarns as the middle layer, viscose yarns as the outer weft yarns, coaxial silver-plated nylon yarns as the inner weft yarns, and Coolmax yarns as Z-axis yarns.

[0009] S3. Cut the elastic cotton fabric as the base fabric, sew elastic bands along the side seams of the chest, shoulders and waist, and fix Velcro at the connection of the elastic bands to obtain the main body of the ECG garment.

[0010] S4. Cut the multi-layered fabric into electrode pieces, sew the electrode pieces to the inside of the ECG garment body according to the twelve-lead monitoring points, and electrically connect the inner weft yarn to the lead wires.

[0011] In a preferred embodiment of the present invention, in step S1, the linear density of the polyester fiber is 100dtex-300dtex, the twist is 500 twists / m-1500 twists / m, the setting temperature is 120℃-150℃, and the setting time is 5min-15min.

[0012] In a preferred embodiment of the present invention, in step S1, the hydrophilic polymer is sodium polyacrylate, with a mass fraction of 8%-16% in the coating solution; the crosslinking agent is citric acid, with a mass fraction of 1%-5% in the coating solution; the immersion bath ratio is 1:10-1:30, and the immersion time is 10 min-30 min; the drying temperature is 60℃-80℃, and the drying time is 30 min-60 min; the thermal crosslinking temperature is 150℃-170℃, and the thermal crosslinking time is 3 min-8 min; the mass ratio of the crosslinked hydrophilic polymer coating attached to the surface of the polyester fiber to the polyester fiber is 10%-20%.

[0013] In a preferred embodiment of the present invention, in step S2, the linear density of the viscose yarn is 50 dtex-150 dtex; the linear density of the coaxial silver-plated nylon yarn is 70 dtex-140 dtex, and the thickness of the silver plating layer is 0.5 μm-2 μm; the linear density of the Coolmax yarn is 80 dtex-200 dtex.

[0014] In a preferred embodiment of the present invention, in step S2, the warp density is 10-20 yarns / cm, the weft density is 10-20 yarns / cm, and the Z-axis yarn density is 5 yarns / cm. 2 -15 roots / cm 2 The compression gap between the super absorbent warp yarn and the inner weft yarn at the interlacing point is 0.1mm-0.5mm.

[0015] In a preferred embodiment of the present invention, in step S3, the weight of the elastic cotton fabric is 150 g / m². 2 -250g / m 2The spandex content is 5%-15%.

[0016] In a preferred embodiment of the present invention, in step S3, the width of the elastic band is 20mm-50mm and the elongation at break is 100%-200%; the width of the Velcro is 15mm-30mm.

[0017] In a preferred embodiment of the present invention, in step S4, the size of the electrode sheet is 40mm×40mm-60mm×60mm.

[0018] In a preferred embodiment of the present invention, in step S4, the suture stitch length is 2mm-5mm.

[0019] To achieve the above objectives, the second technical solution adopted by the present invention is: a wearable 12-lead ECG monitoring garment with unidirectional moisture-wicking properties, which is prepared by a method for preparing a wearable 12-lead ECG monitoring garment with unidirectional moisture-wicking properties.

[0020] This invention addresses the shortcomings of the prior art and has the following beneficial effects:

[0021] (1) This invention provides a method for preparing a wearable 12-lead ECG monitoring garment with unidirectional moisture-wicking properties. The surface cross-linked hydrophilic polymer network captures liquid water through hydrophilic groups and undergoes radial swelling to lock in moisture and eliminate flow potential. The specific three-dimensional spatial conformation of the spirally coiled fiber provides the cross-linked polymer network with attachment carriers of various shapes and continuous gap channels, avoiding disordered accumulation of polymer on the fiber surface, ensuring effective coating and mechanical constraint of the rigid network on the substrate, inhibiting the mechanical property degradation caused by pore channel blockage and plastic slippage of the hydrogel phase, so that while absorbing and locking in interfacial sweat to eliminate flow potential, the electrode structure is morphologically stable in wet conditions and the moisture-wicking function is sustained. This fundamentally solves the signal distortion problem caused by sweat accumulation and deterioration of fit, and achieves signal stability under high-precision long-term continuous monitoring.

[0022] (2) In this invention, the surface cross-linked hydrophilic polymer network captures liquid water through hydrophilic groups and establishes capillary force gradient to drive the directional migration of water. At the same time, its molecular chain conformation provides mass transfer channels to promote the diffusion of gaseous water. The specific three-dimensional spatial conformation of the helical coiled fiber provides the cross-linked polymer network with attachment carriers of various shapes and continuous gap channels, avoiding the disordered accumulation of polymer on the fiber surface, ensuring the effective coating and pore connectivity of the network structure, so as to construct an efficient liquid-gas bidirectional conduction path while maintaining the tensile properties of the fiber body. While realizing the rapid directional conduction of sweat, it also ensures the breathability of the microclimate, thereby effectively eliminating the sweat accumulation defect of the monitoring garment.

[0023] (3) In this invention, the surface cross-linked hydrophilic polymer network absorbs sweat at the interface and undergoes radial swelling to lock in liquid water and eliminate flow potential. At the same time, it generates volume expansion stress. The specific helical angle of the spirally coiled fiber optimizes the three-dimensional spatial conformation and provides abundant mechanical interlocking sites for the cross-linked polymer network. This allows the volume expansion stress generated by swelling to be effectively guided and transformed into micro-extrusion force in the direction of the inner conductive yarn. The two work together to force the conductive layer to closely adhere to the skin contour and displace the residual liquid film, fundamentally eliminating the increase in contact impedance and artifact interference caused by insufficient adhesion, and achieving signal stability under high-precision long-term continuous monitoring. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a flowchart illustrating the method steps of a preferred embodiment of the present invention;

[0026] Figure 2 This is a schematic diagram of a wearable 12-lead ECG monitoring garment with unidirectional moisture-wicking properties, according to a preferred embodiment of the present invention. Detailed Implementation

[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein. Therefore, the scope of protection of the invention is not limited to the specific embodiments disclosed below.

[0029] Application Overview:

[0030] Traditional ECG monitoring clothing faces a dilemma in addressing sweating interference. When the body sweats, a free water film forms between the skin and the electrodes. This film fluctuates with body movement, directly causing severe distortion of the monitoring signal. Relying solely on physical sweat-wicking structures to expel moisture is insufficient to completely remove trace amounts of residual sweat from the contact surface, leaving interference unresolved. On the other hand, increasing the physical pressure on the electrodes to achieve signal stability can block the sweat's expulsion channels, leading to sweat accumulation. Thus, moisture wicking and signal stability become a mutually constraining contradiction.

[0031] This application resolves the aforementioned contradiction by constructing a water-absorbing and swelling cross-linked network on the surface of specific crimped fibers and strictly limiting the coverage area of ​​the electrode pads. When sweat appears, the cross-linked network on the fiber surface rapidly absorbs moisture and expands in volume. This expansion directly compresses the internal conductive yarns, making them more closely conform to the contours of the body and expelling residual moisture, thus combining the sweat-wicking and conforming actions into one. Simultaneously, by controlling the electrode pads within a specific size range, the structural compactness of the edge areas is ensured, preventing the edges from loosening due to excessive area and losing effective compression of the conductive yarns, thereby guaranteeing the overall coordination and consistency of moisture wicking and conforming actions.

[0032] Based on the above mechanism, this ECG monitoring garment can still maintain a dry and stable contact interface even when the user sweats heavily or the garment does not fit properly. It not only actively absorbs and locks in sweat at the skin contact point, completely eliminating signal interference caused by water film fluctuations, but also ensures efficient and unobstructed conductive pathways through adaptive compression and fit. Ultimately, it achieves long-term, imperceptible monitoring in complex and dynamic environments, balancing the accurate acquisition of medical-grade signals with the comfort of everyday wear.

[0033] Procurement of materials:

[0034] Polyester fiber: purchased from Jiangsu Hengli Chemical Fiber Co., Ltd., model 150dtex / 48f, semi-dull;

[0035] Viscose yarn: purchased from Jilin Chemical Fiber Co., Ltd., model 100dtex / 40f, bright;

[0036] Coaxial silver-plated nylon yarn: purchased from Shanghai Heshen Technology Co., Ltd., model 110dtex / 34f, nylon base material is nylon 6, silver plating thickness is 1.2μm, silver mass fraction is 20%;

[0037] Coolmax yarn: purchased from Invista, USA, model 120dtex / 72f, four-groove cross section;

[0038] Elastic cotton fabric: purchased from Guangdong Foshan Jianye Textile Co., Ltd., with a weight of 200g / m², a spandex mass fraction of 10%, and both warp and weft yarns are 40S combed cotton and 40D spandex core-spun yarn;

[0039] Elastic band: Purchased from Jiajie Belt Industry Co., Ltd. in Yiwu City, Zhejiang Province; width 30mm; elongation at break 150%; nylon-spandex blend.

[0040] Velcro: Purchased from Zhejiang Weixing New Material Development Co., Ltd., width 20mm, adhesive backing, peel strength 15N / cm;

[0041] Sodium polyacrylate: purchased from Sinopharm Chemical Reagent Co., Ltd., analytical grade, molecular weight 5 million;

[0042] Citric acid: purchased from Sinopharm Chemical Reagent Co., Ltd., analytical grade, mass fraction ≥99.5%.

[0043] Homemade materials:

[0044] Artificial sweat: Weigh 0.5g sodium chloride, 0.1g lactic acid, and 0.2g urea, dissolve them in 100mL deionized water, and adjust the pH to 6.5 using 0.1mol / L sodium hydroxide solution.

[0045] like Figure 1 and Figure 2 As shown, a method for preparing a wearable 12-lead ECG monitoring garment with unidirectional moisture-wicking properties includes the following steps:

[0046] S1. Twist and set polyester fibers to obtain spiral crimped fibers; prepare a coating solution by mixing hydrophilic polymer, crosslinking agent and water; immerse the spiral crimped fibers in the coating solution; and obtain super absorbent warp yarns after drying and thermal crosslinking treatment.

[0047] S2. Multi-layer fabrics are prepared using a three-dimensional orthogonal weaving process with super absorbent warp yarns as the middle layer, viscose yarns as the outer weft yarns, coaxial silver-plated nylon yarns as the inner weft yarns, and Coolmax yarns as Z-axis yarns.

[0048] S3. Cut the elastic cotton fabric as the base fabric, sew elastic bands along the side seams of the chest, shoulders and waist, and fix Velcro at the connection of the elastic bands to obtain the main body of the ECG garment.

[0049] S4. Cut the multi-layered fabric into electrode pieces, sew the electrode pieces to the inside of the ECG garment body according to the twelve-lead monitoring points, and electrically connect the inner weft yarn to the lead wires.

[0050] In step S1:

[0051] The linear density of polyester fiber is 100dtex-300dtex, the twist is 500 twists / m-1500 twists / m, the setting temperature is 120℃-150℃, and the setting time is 5min-15min.

[0052] The hydrophilic polymer is sodium polyacrylate, with a mass fraction of 8%-16% in the coating solution; the crosslinking agent is citric acid, with a mass fraction of 1%-5% in the coating solution; the immersion bath ratio is 1:10-1:30, and the immersion time is 10-30 min; the drying temperature is 60℃-80℃, and the drying time is 30-60 min; the thermal crosslinking temperature is 150℃-170℃, and the thermal crosslinking time is 3-8 min; the mass ratio of the crosslinked hydrophilic polymer coating adhering to the surface of the polyester fiber to the polyester fiber is 10%-20%.

[0053] The glass transition temperature of polyester fiber is around 80℃. When it is twisted and maintained within this temperature range, the polyester macromolecular chain segments rearrange. After the twisting is released and the fiber is cooled, the macromolecular chain segments are frozen in the new conformation. Due to the difference in orientation of the macromolecular chains on the inner and outer sides of the fiber axis, the internal stress is released, and the fiber undergoes irreversible helical spatial curling, thus forming helical curled fiber.

[0054] Spiral crimped fibers refer to fiber structures that exhibit a continuous spiral geometric conformation along the fiber axis. The spiral period is 2mm-3mm, the spiral diameter is 0.1mm-0.5mm, and the spiral helix angle is 30°-60°. This structure generates internal stress through differences in molecular chain orientation, and produces a permanent three-dimensional crimped shape after the external force is released.

[0055] When polyester fibers are twisted within the glass transition temperature range, different molecular chain orientations are generated on the inner and outer sides of the fiber axis. After the twisting is released, due to the release of internal stress, the molecular chains undergo asymmetric retraction, forming a stable helical conformation. This structure provides a larger specific surface area and mechanical interlocking sites for subsequent coating treatments.

[0056] The carboxyl groups on the sodium polyacrylate molecular chain undergo an esterification reaction with the carboxyl groups of citric acid at high temperature, forming a three-dimensional cross-linked network.

[0057] In step S2:

[0058] The linear density of viscose yarn is 50dtex-150dtex; the linear density of coaxial silver-plated nylon yarn is 70dtex-140dtex, and the silver plating thickness is 0.5μm-2μm; the linear density of Coolmax yarn is 80dtex-200dtex.

[0059] The warp density is 10-20 yarns / cm, the weft density is 10-20 yarns / cm, and the Z-axis yarn density is 5 yarns / cm.2 -15 roots / cm 2 The compression gap between the super absorbent warp yarn and the inner weft yarn at the interlacing point is 0.1mm-0.5mm.

[0060] Coolmax yarn uses polyester fiber with an irregular cross-section. The cross-section is a four-groove cross shape with a groove depth of 2μm-5μm, a groove angle of 90°, a fiber filament fineness of 1.5dtex-3.0dtex, and a surface contact angle of 60°-75°.

[0061] Three-way orthogonal weaving refers to a weaving method that uses a three-dimensional loom to interweave warp yarns, weft yarns, and Z-axis yarns in mutually perpendicular directions. The warp yarns are arranged along the length of the fabric, the first weft yarn is arranged along the width of the fabric, the second weft yarn is parallel to the first weft yarn but located in a different layer, and the Z-axis yarn runs through each layer along the thickness of the fabric, forming a three-dimensional interlocking structure.

[0062] Z-axis yarns refer to yarns arranged along the thickness direction in a three-dimensional fabric structure. Their function is to connect and fix the warp and weft yarns in the thickness direction to form a stable interlayer bond. The arrangement of Z-axis yarns is a rectangular array or a diamond array, and the spacing between adjacent Z-axis yarns is 1mm-5mm.

[0063] When the four-groove cross-section structure of Coolmax fiber is arranged in the Z-direction, the groove direction is parallel to the fabric thickness direction, forming a capillary array. Its surface tension gradient can drive water to move directionally along the thickness direction. In addition, the fiber has high crystallinity and good dimensional stability, making it suitable as a Z-direction connecting yarn.

[0064] The Z-axis yarn threading method adopts a stepped threading, with a 2-3mm interval between each layer of warp yarns; the loom shedding mechanism movement law is electronically jacquard controlled, with an shedding time of 250ms and a closing time of 150ms; the interlayer interweaving sequence is warp-weft 1-warp-weft 2-warp-Z-axis yarn cycle; the weaving tension is controlled at 0.3-0.5cN / dtex, the weaving speed is 80-120rpm, the loom temperature is 25±2℃, and the humidity is 60±5%RH to ensure the accuracy and repeatability of the three-dimensional structure.

[0065] The Z-axis yarns are arranged in a rectangular array with a spacing of 2mm×2mm between adjacent Z-axis yarns; or in a diamond array with a spacing of 1.5mm between adjacent Z-axis yarns and a diamond angle of 60°.

[0066] In step S3:

[0067] The weight of elastic cotton fabric is 150g / m². 2 -250g / m 2 The spandex content is 5%-15%.

[0068] The elastic band has a width of 20mm-50mm and a breaking elongation of 100%-200%; the Velcro has a width of 15mm-30mm.

[0069] In step S4:

[0070] The electrode sheet dimensions are 40mm×40mm-60mm×60mm.

[0071] The stitch spacing is 2mm-5mm.

[0072] The sewing equipment for the electrode sheet sewing process is a computerized embroidery machine with a DB×1 needle, a needle tip angle of 25°, polyester filament thread with a linear density of 40dtex, a top thread tension of 8cN-12cN, a bottom thread tension of 6cN-10cN, a presser foot pressure of 40N-60N, and a sewing speed of 800rpm-1200rpm.

[0073] The electrode pads should be sutured as follows: for the precordial leads, V1 should be placed at the right sternal border in the 4th intercostal space, V2 at the left sternal border in the 4th intercostal space, V3 at the midpoint of the line connecting V2 and V4, V4 at the left midclavicular line in the 5th intercostal space, V5 at the left anterior axillary line at the same level as V4, and V6 at the left midaxillary line at the same level as V4. For the limb leads, RA (right arm), LA (left arm), RL (right leg), and LL (left leg), they should be placed at the proximal end of the corresponding limb, with RL serving as the ground electrode. The specific positions should conform to the AHA / ACC / HRS standard lead positioning requirements to ensure the clinical accuracy of ECG monitoring.

[0074] After swelling, the hydrophilic polymer (sodium polyacrylate) eliminates the flow potential through a dual mechanism: first, the ion adsorption neutralization mechanism, where a large number of carboxylate groups (-COO⁻) in the swollen sodium polyacrylate network adsorb cations such as Na⁺ and K⁺ in sweat, forming an electric double layer at the polymer-liquid interface, neutralizing the potential difference generated by the flow; second, the spatial confinement mechanism, where the swollen polymer network fills the gaps between fibers, dividing sweat into tiny droplets, restricting the overall flow of the liquid phase, and transforming macroscopic flow into microscopic diffusion, fundamentally eliminating the conditions for the generation of flow potential.

[0075] After absorbing sweat, the cross-linked hydrophilic polymer network undergoes radial swelling. However, this swelling is constrained by the spatial constraints of the Z-axis yarn in the triaxial orthogonal structure, forcing the volume expansion to be converted into directional pressure along the fabric thickness direction. At the same time, the four-groove cross-section structure of Coolmax yarn and the gap between the spiral crimped fibers form a capillary network. By controlling the surface energy difference between the inner and outer fibers, a capillary force gradient is established from the inside to the outside. The two mechanisms work together: radial swelling provides the driving force, and the capillary force gradient provides the directionality, jointly realizing the unidirectional migration of sweat from the skin side to the air side.

[0076] Super absorbent warp yarn refers to yarn that, under standard test conditions (25℃, 65%RH), has an absorption rate of 300%-500% (by mass) of artificial sweat, reaches more than 80% of its saturated absorbency within 30 seconds, retains no less than 60% of its moisture content under a centrifugal force of 300g, and exhibits a moisture absorption performance decrease of no more than 15% after 1000 dynamic bending cycles. These indicators are determined according to the standard method of GB / T21655.1-2008 "Evaluation of the Moisture Absorption and Quick-Drying Properties of Textiles".

[0077] The normal preload provided by the elastic band should be controlled within the range of 0.5-2.0 N / cm², calculated using the breaking elongation (100%-200%) and width (20mm-50mm) parameters of the elastic band. When worn, the compression force of the ECG garment on the chest should be maintained at 10-30 mmHg (equivalent to the medium pressure level of medical compression stockings). A pressure sensor array is used to measure the pressure distribution under different body positions (sitting, standing, and exercising) to ensure that sufficient interfacial fit is provided without affecting blood circulation and breathing comfort.

[0078] To achieve the above objectives, the second technical solution adopted by the present invention is: a wearable 12-lead ECG monitoring garment with unidirectional moisture-wicking properties, which is prepared by a method for preparing a wearable 12-lead ECG monitoring garment with unidirectional moisture-wicking properties.

[0079] Example 1:

[0080] A method for preparing a wearable 12-lead ECG monitoring garment with unidirectional moisture-wicking properties includes the following steps:

[0081] S1. Twist and set polyester fibers to obtain spiral crimped fibers; prepare a coating solution by mixing hydrophilic polymer, crosslinking agent and water; immerse the spiral crimped fibers in the coating solution; and obtain super absorbent warp yarns after drying and thermal crosslinking treatment.

[0082] The polyester fiber has a linear density of 220 dtex, a twist of 750 twists / m, a setting temperature of 130℃, and a setting time of 8 min.

[0083] The hydrophilic polymer is sodium polyacrylate, with a mass fraction of 8% in the coating solution; the crosslinking agent is citric acid, with a mass fraction of 2% in the coating solution; the immersion bath ratio is 1:10, the immersion time is 20 min; the drying temperature is 70℃, the drying time is 45 min; the thermal crosslinking temperature is 150℃, and the thermal crosslinking time is 6 min.

[0084] The spiral diameter of the spiral crimped fiber is 0.1 mm, and the spiral helix angle is 30°.

[0085] S2. Multi-layer fabrics are prepared using a three-dimensional orthogonal weaving process with super absorbent warp yarns as the middle layer, viscose yarns as the outer weft yarns, coaxial silver-plated nylon yarns as the inner weft yarns, and Coolmax yarns as Z-axis yarns.

[0086] The linear density of the viscose yarn is 80 dtex; the linear density of the coaxial silver-plated nylon yarn is 100 dtex, and the silver plating thickness is 1 μm; the linear density of the Coolmax yarn is 160 dtex.

[0087] The warp density is 14 yarns / cm, the weft density is 16 yarns / cm, and the Z-axis yarn density is 6 yarns / cm. 2 The compression gap between the super absorbent warp yarn and the inner weft yarn at the interlacing point is 0.3mm.

[0088] Coolmax yarn is made of polyester fiber with an irregular cross section. The cross section is a four-groove cross shape with a groove depth of 3μm, a groove angle of 90°, a fiber filament fineness of 2.0dtex, and a surface contact angle of 75°.

[0089] S3. Cut the elastic cotton fabric as the base fabric, sew elastic bands along the side seams of the chest, shoulders and waist, and fix Velcro at the connection of the elastic bands to obtain the main body of the ECG garment.

[0090] The weight of elastic cotton fabric is 200g / m². 2 The spandex content is 9%, and the elastic cotton fabric has a 1×1 rib knit structure.

[0091] The elastic band is 30mm wide and has an elongation at break of 150%; the Velcro is 20mm wide.

[0092] S4. Cut the multi-layered fabric into electrode pieces, sew the electrode pieces to the inside of the ECG garment body according to the twelve-lead monitoring points, and electrically connect the inner weft yarn to the lead wires.

[0093] The electrode sheet measures 40mm × 40mm.

[0094] The stitch length is 3mm.

[0095] The sewing equipment for the electrode sheet sewing process is a computerized embroidery machine with a DB×1 needle, a needle tip angle of 25°, polyester filament thread with a linear density of 40dtex, a top thread tension of 10cN, a bottom thread tension of 6cN, a presser foot pressure of 50N, and a sewing speed of 1000rpm.

[0096] Example 2:

[0097] The difference between this embodiment and Embodiment 1 is that the mass fraction of sodium polyacrylate in the coating liquid is 12%, while the rest are the same.

[0098] Example 3:

[0099] The difference between this embodiment and Embodiment 1 is that the mass fraction of sodium polyacrylate in the coating liquid is 16%, while the rest are the same.

[0100] Example 4:

[0101] The difference between this embodiment and Embodiment 2 is that the helix angle is 45°, while the rest are the same.

[0102] Example 5:

[0103] The difference between this embodiment and Embodiment 2 is that the helix angle is 60°, while the rest are the same.

[0104] Comparative Example 1:

[0105] The difference between this comparative example and Example 1 is that the mass fraction of sodium polyacrylate in the coating liquid is 4%, while the rest are the same.

[0106] Comparative Example 2:

[0107] The difference between this comparative example and Example 1 is that the mass fraction of sodium polyacrylate in the coating liquid is 20%, while the rest are the same.

[0108] Comparative Example 3:

[0109] The difference between this comparative example and Example 2 is that the helix angle is 15°, while the rest are the same.

[0110] Comparative Example 4:

[0111] The difference between this comparative example and Example 2 is that the helix angle is 75°, while the rest are the same.

[0112] Comparative Example 5:

[0113] The difference between this comparative example and Example 2 is that the coating liquid contains only a crosslinking agent and water. The crosslinking agent is citric acid, which has a mass fraction of 2% in the coating liquid. The rest are the same.

[0114] Comparative Example 6:

[0115] The difference between this comparative example and Example 2 is that the Z-direction yarn is a circular cross-section polyester fiber with a linear density of 160 dtex, while the rest are the same.

[0116] Experiment 1:

[0117] Five parallel samples were taken from each of the fabric electrode samples prepared in Examples 1-3, Comparative Examples 1-2, and Comparative Examples 5-6, and the following tests were performed.

[0118] 1. Unidirectional Moisture Conduction Test: The OCA40Micro optical contact angle meter was used to measure the surface wettability of the hydrophobic surface of the textile electrode (silver-plated nylon). During the test, a 5 μL water droplet was added to the surface of the hydrophobic layer of the fabric, and a Nikon camera was used to capture digital images to record the penetration time of the fabric. The SCA20 was used to measure the change in the water contact angle of the water droplet on the fabric surface. The penetration time of the water droplet from the outer layer to the inner layer of the fabric was recorded.

[0119] 2. Air permeability test: Using a fully automatic air permeability measuring instrument (model YG461E), the sample is clamped in the test chamber, the test pressure difference is set to 200Pa, the instrument automatically records the air volume passing through the sample within 1 minute, and calculates the air permeability per unit time (mm / s). Each sample is tested twice, with an interval of 10s to allow for equilibrium.

[0120] 3. Elongation at break test: Using a universal testing machine (model Instron5969), the sample was cut into strips of 5cm×1cm and clamped in the upper and lower clamps (clamping distance 3cm). The tensile rate was set to 50mm / min, and the elongation at break was recorded. The elongation at break was calculated by the formula (elongation at break / initial clamping distance)×100%. Each sample was tested 3 times, and the average value was taken after removing outliers.

[0121] All test data were rounded to one decimal place. The mean and standard deviation of each sample group were calculated to ensure data accuracy and repeatability. The results are shown in the table below:

[0122] Table 1 Comparison of Experimental Results for Unidirectional Moisture Conduction and Breathability

[0123] Example 1 0.7 95.75 Example 2 0.5 103.6 Example 3 0.8 99.2 Comparative Example 1 1 92.3 Comparative Example 2 1.1 91.5 Comparative Example 5 3.2 110.6 Comparative Example 6 2.4 89.5

[0124] As shown in Table 1, the mass fraction of sodium polyacrylate in the coating solution affects the unidirectional moisture conduction performance and water vapor transmission rate of the electrode.

[0125] In Examples 1-3 and Comparative Examples 1-2, as the mass fraction of sodium polyacrylate in the coating liquid gradually increased, both the unidirectional hygroscopic performance and water vapor transmission rate first increased and then decreased. This is because, as the mass fraction of sodium polyacrylate in the coating liquid gradually increased, the cross-linked network was gradually and perfectly constructed on the fiber surface and within the gaps of the spiral coils. The increased density of hydrophilic groups significantly enhanced the wettability of the interface and strengthened the capillary gradient effect, promoting the rapid directional migration of liquid water. At the same time, the mass transfer channels provided by the hydrophilic molecular chain conformation accelerated the diffusion and conduction of gaseous water molecules. However, when the mass fraction increased too much, the excess polymer caused the cross-linked coating thickness to exceed the limit and completely fill the spiral coil space. The resulting continuous and dense barrier layer cut off the original pore conduction path and caused internal liquid water accumulation, severely hindering both the unidirectional transport of liquid water and the penetration and diffusion of gaseous water. Example 2 is the preferred embodiment among Examples 1-3.

[0126] Comparative Example 5, lacking a cross-linked hydrophilic polymer network, could not construct a continuous gradient wetting layer and a directional capillary force driving mechanism on the fiber surface. Liquid water could only migrate through passive physical diffusion in macroscopic pores, resulting in a significantly slow dynamic process of water permeation from the inner layer to the outer layer. Meanwhile, since the fiber gaps were not occupied by the polymer gel phase, the pore channels inside the three-dimensional orthogonal structure remained completely open, and the diffusion and conduction path of gaseous water molecules was not disturbed by any steric hindrance effect, thus exhibiting the best air permeability and breathability.

[0127] Comparative Example 6 uses circular cross-section polyester fiber for the Z-direction yarn, which loses the directional capillary array and surface tension gradient built by the irregular groove structure in the thickness direction. This results in a lack of strong suction force for liquid water in the transmission path perpendicular to the fabric plane, causing a decrease in the microscopic conduction rate of unidirectional moisture conduction. At the same time, the circular cross-section yarn is more tightly geometrically interlocked with the warp and weft yarns during the three-dimensional orthogonal interlacing process, which destroys the interlayer vertical micro-airflow channels maintained by the original groove structure. This leads to a decrease in the pore connectivity in the fabric thickness direction and an increase in the viscous resistance when gas molecules penetrate, thereby deteriorating the air permeability.

[0128] Experiment 2:

[0129] Examples 2, 4-5 and Comparative Examples 3-6 were selected, with 5 parallel samples taken from each group, and the following tests were conducted.

[0130] 1. Electrode-skin interface impedance: The electrode-skin interface impedance was measured using an electrochemical workstation CHI660D.

[0131] 2. Signal-to-Noise Ratio (SNR) Test: The quality of an electrocardiogram (ECG) signal can be evaluated using the signal-to-noise ratio (SNR, unit: dB). The SNR is the ratio of the power of the effective components in the signal to the power of the noise components, calculated using the formula:

[0132]

[0133] in, It is the effective signal voltage in mV. This is the noise voltage measured in mV. Furthermore, a higher signal-to-noise ratio generally indicates better quality of the acquired ECG signal.

[0134] This experiment involved fixing electrodes of different embodiments onto the subject, who then performed a 90° arm swing motion for an extended period.

[0135] Table 2 Comparison of Experimental Results for Interface Impedance and Signal-to-Noise Ratio

[0136] Example 2 284 34.3 Example 4 276 35.7 Example 5 287 32.1 Comparative Example 3 325 22.3 Comparative Example 4 389 19.1 Comparative Example 5 673 7.5 Comparative Example 6 596 15.2

[0137] As shown in Table 2, the helix angle of the spirally coiled fiber affects the key performance characteristics of the electrode, such as the skin-interface impedance and the signal-to-noise ratio under dynamic conditions.

[0138] As the helix angle of the helical crimped fiber gradually increases, the impedance value first decreases and then increases, while the signal-to-noise ratio (SNR) first increases and then decreases. This is because as the helix angle of the helical crimped fiber gradually increases, a moderate helix angle optimizes the three-dimensional spatial conformation of the fiber, providing richer mechanical interlocking sites and effective specific surface area for the cross-linked polymer network. This allows the volume expansion of the polymer after hygroscopic swelling to be fully constrained by the triaxial orthogonal structure and efficiently converted into inward microscopic extrusion force, forcing the conductive layer to tightly adhere to the skin contour and displace residual liquid film, thereby reducing contact impedance and improving the SNR. However, when the helix angle increases too much, the overly steep helical conformation causes structural compression and collapse of the interfiber channels, disrupting the uniform and continuous adhesion and spatial distribution of the cross-linked polymer network on the substrate surface. This causes the swelling deformation to lose a continuous and effective mechanical force transmission path and cannot be converted into uniform microscopic extrusion force, resulting in localized loosening of adhesion and liquid film residue, which in turn causes a rebound increase in impedance value and a deterioration and attenuation of the SNR. The best embodiment is Example 4.

[0139] Comparative Example 5, lacking a cross-linked hydrophilic polymer network, cannot undergo radial swelling to generate inward micro-compression when wetted by sweat. This results in the conductive layer failing to adhere tightly to the skin contour under dynamic deformation. Furthermore, free sweat accumulates at the interface, forming an insulating liquid film accompanied by the generation of micro-air gaps, significantly increasing charge transfer resistance. The macroscopic flow of free sweat during dynamic arm swinging excites strong electrochemical noise, while the relative slippage caused by interface adhesion failure introduces large-scale motion artifacts, severely obscuring the effective electrocardiogram signal.

[0140] Although Comparative Example 6 possesses the mechanical conduction mechanism of polymer swelling and extrusion to maintain basic adhesion, the circular cross-section vertical yarn system loses the capillary suction guiding effect of the irregular grooves, resulting in obstruction of the unidirectional moisture-guiding path. Liquid water cannot be effectively channeled outward and micro-area accumulation occurs at the skin-electrode interface. This accumulated liquid film, as an additional dielectric layer, significantly increases the interfacial contact impedance, making its impedance level between Comparative Example 5, which completely loses the ability to expel liquid film, and Example 4, which possesses an efficient liquid expulsion and extrusion synergistic mechanism. Although the swelling and extrusion of the cross-linked network can suppress mechanical friction artifacts caused by loose adhesion, the obstruction of sweat excretion caused by the circular cross-section yarn makes the residual liquid film at the interface in an unsteady fluctuation state, continuously generating local flow potential fluctuation interference. Furthermore, the uneven distribution of the liquid film thickness changes the local electric field distribution and introduces additional electrochemical polarization noise. Therefore, although its signal-to-noise ratio is better than that of the comprehensively degraded Comparative Example 5, it is still lower than that of Example 4 because it fails to achieve absolute dryness and electrical stability at the interface.

[0141] Based on the preferred embodiments of the present invention described above, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A method for preparing a wearable 12-lead ECG monitoring garment with unidirectional moisture-wicking properties, comprising the following steps: S1. Twist and set polyester fibers to obtain spiral crimped fibers; prepare a coating solution by mixing hydrophilic polymer, crosslinking agent and water; immerse the spiral crimped fibers in the coating solution; and obtain super absorbent warp yarns after drying and thermal crosslinking treatment. S2. Multi-layer fabrics are prepared using a three-dimensional orthogonal weaving process with super absorbent warp yarns as the middle layer, viscose yarns as the outer weft yarns, coaxial silver-plated nylon yarns as the inner weft yarns, and Coolmax yarns as Z-axis yarns. S3. Cut the elastic cotton fabric as the base fabric, sew elastic bands along the side seams of the chest, shoulders and waist, and fix Velcro at the connection of the elastic bands to obtain the main body of the ECG garment; S4. Cut the multi-layered fabric into electrode pieces, sew the electrode pieces to the inside of the ECG garment body according to the twelve-lead monitoring points, and electrically connect the inner weft yarn to the lead wires.

2. The method for preparing a wearable 12-lead ECG monitoring garment with unidirectional moisture-wicking properties according to claim 1, characterized in that: In step S1, the linear density of the polyester fiber is 100dtex-300dtex, the twist is 500 twists / m-1500 twists / m, the setting temperature is 120℃-150℃, and the setting time is 5min-15min.

3. The method for preparing a wearable 12-lead ECG monitoring garment with unidirectional moisture-wicking properties according to claim 1, characterized in that: In step S1, the hydrophilic polymer is sodium polyacrylate, with a mass fraction of 8%-16% in the coating solution; the crosslinking agent is citric acid, with a mass fraction of 1%-5% in the coating solution; the immersion bath ratio is 1:10-1:30, and the immersion time is 10 min-30 min; the drying temperature is 60℃-80℃, and the drying time is 30 min-60 min; the thermal crosslinking temperature is 150℃-170℃, and the thermal crosslinking time is 3 min-8 min; the mass ratio of the crosslinked hydrophilic polymer coating attached to the surface of the polyester fiber to the polyester fiber is 10%-20%.

4. The method for preparing a wearable 12-lead ECG monitoring garment with unidirectional moisture-wicking properties according to claim 1, characterized in that: In step S2, the linear density of the viscose yarn is 50 dtex-150 dtex; the linear density of the coaxial silver-plated nylon yarn is 70 dtex-140 dtex, and the thickness of the silver plating layer is 0.5 μm-2 μm; the linear density of the Coolmax yarn is 80 dtex-200 dtex.

5. The method for preparing a wearable 12-lead ECG monitoring garment with unidirectional moisture-wicking properties according to claim 1, characterized in that: In step S2, the warp density is 10-20 yarns / cm, the weft density is 10-20 yarns / cm, and the Z-axis yarn density is 5 yarns / cm. 2 -15 roots / cm 2 The compression gap between the super absorbent warp yarn and the inner weft yarn at the interlacing point is 0.1mm-0.5mm.

6. The method for preparing a wearable 12-lead ECG monitoring garment with unidirectional moisture-wicking properties according to claim 1, characterized in that: In step S3, the weight of the elastic cotton fabric is 150 g / m². 2 -250g / m 2 The spandex content is 5%-15%.

7. The method for preparing a wearable 12-lead ECG monitoring garment with unidirectional moisture-wicking properties according to claim 1, characterized in that: In step S3, the elastic band has a width of 20mm-50mm and a breaking elongation of 100%-200%; the Velcro has a width of 15mm-30mm.

8. The method for preparing a wearable 12-lead ECG monitoring garment with unidirectional moisture-wicking properties according to claim 1, characterized in that: In step S4, the size of the electrode sheet is 40mm×40mm-60mm×60mm.

9. The method for preparing a wearable 12-lead ECG monitoring garment with unidirectional moisture-wicking properties according to claim 1, characterized in that: In step S4, the stitch length is 2mm-5mm.

10. A wearable 12-lead ECG monitoring garment with unidirectional moisture-wicking properties, characterized in that, The wearable 12-lead ECG monitoring garment with unidirectional moisture-wicking properties was prepared according to any one of claims 1-9.

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