Stretchable conductive signal line and method of making and using same

Abstract

This invention relates to a stretchable conductive signal wire, its preparation method, and its application. The product includes an elastic layer, a conductive layer, and an insulating layer. The elastic layer is composed of elastomer wire, and the conductive layer is composed of conductive wire. The conductive wire is wound in a helical manner around the outer wall of a pre-stretched elastomer wire. The insulating layer covers the outer walls of the elastic layer and the conductive layer. The diameter of the conductive wire is ≥100μm, the helical spacing of the conductive wire is ≥50μm and ≤1.5mm, and the diameter of the elastomer wire is ≥400μm. First, the conductive wire is wound in a helical manner around the outer wall of the pre-stretched elastomer wire to obtain a composite wire. Then, an insulating layer is formed on the outer wall of the composite wire to obtain the stretchable conductive signal wire. The application is as a signal connection wire for electronic devices in smart clothing. The product of this invention has excellent tensile-recovery stability and tensile-conductivity stability; the preparation method is simple; and it can be applied to different parts of smart clothing.

Description

Technical Field

[0001] This invention belongs to the field of smart clothing technology, and relates to a stretchable conductive signal line, its preparation method, and its application. Background Technology

[0002] Smart clothing, as an emerging field integrating technology and fashion, has attracted increasing attention and demand. People's demand for smart clothing is constantly increasing, with many hoping to improve their quality of life, monitor their health, and increase comfort by wearing smart garments. Flexible conductive signal lines are an indispensable part of smart clothing, used to transmit data and electrical signals, enabling the clothing to interact with external devices. However, flexible conductive signal lines currently face some problems, affecting the performance and reliability of smart clothing. Specific issues include:

[0003] (1) The durability of the elastic conductive wires still needs to be improved. During wearing and washing, the elastic conductive wires of smart clothing are easily stretched and twisted, which can lead to wire breakage or damage, thereby affecting the function and service life of the clothing.

[0004] (2) The elastic conductive wire has poor tensile recovery performance, meaning that after repeated stretching, the wire cannot fully return to its original length. This problem can lead to slack and deformation of the wire, which in turn affects the integrity and reliability of smart clothing.

[0005] (3) The conductivity of flexible conductive wires may be affected by environmental factors. For example, a humid environment or sweat may cause oxidation on the surface of the conductive wire, reducing its conductivity and even causing safety problems such as short circuits.

[0006] Furthermore, under high tensile stress and strain requirements, thinner conductive signal lines (diameter less than 100μm) are prone to breakage, thus affecting the signal transmission of stretchable wires. For example, the stretchable elastic conductive wire bundle prepared in patent CN110387621B uses wires with a diameter of 100μm or less, which are prone to breakage during use. Therefore, in specific applications, such as wiring in areas with large body bending angles (e.g., elbows, knees), the elastic conductive signal line needs to have a large elongation rate. Choosing conductive wires with a diameter of 100μm or more can avoid breakage and circuit breakage. However, when the diameter of the conductive wire increases to more than 100μm, due to the flexibility and non-uniform geometry of the conductive signal line, lateral forces will be generated at certain locations. Although the presence of such lateral forces does not necessarily lead to macroscopic lateral deformation of the conductive signal line, when the lateral force exceeds the critical bending yield force of the conductive signal line, the macroscopically uncontrollable lateral deformation will prevent the wire from returning to its original straight configuration, thus affecting the tensile cycle stability.

[0007] Therefore, it is of great significance to study a stretchable conductive signal line with a diameter ≥100μm, its preparation method and application, in order to solve the problems existing in the prior art. Summary of the Invention

[0008] The purpose of this invention is to solve the problems existing in the prior art and to provide a stretchable conductive signal line, its preparation method, and its application.

[0009] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0010] A stretchable conductive signal line includes an elastic layer, a conductive layer, and an insulating layer; the elastic layer is composed of an elastic wire, the conductive layer is composed of a conductive wire, and the conductive wire is wound in a spiral rotation around the outer wall of a pre-stretched elastic wire; the insulating layer covers the outer walls of the elastic layer and the conductive layer.

[0011] The diameter of the conductive wire is ≥100μm, the helix pitch of the conductive wire is ≥50μm and ≤1.5mm, and the diameter of the elastomer wire is ≥400μm;

[0012] The conductive layer is wound around the outer wall of the elastic layer wire in a spiral rotation manner, forming a certain spiral spacing. The diameter of the elastic layer and the spiral spacing of the conductive layer have a certain synergistic effect, thereby enabling the elastic layer and the conductive layer to achieve physical interlocking and fixation. The insulating layer encapsulates the outer wall of the conductive layer and the elastic layer, which not only improves the tensile strength of the stretchable conductive signal line, but also achieves the effect of insulation.

[0013] The range of the helical spacing should be within the set range. If the helical spacing is too large, it cannot fit the elastomer wire, and the helical conformation will detach from the elastomer in a relaxed state, which is defined as a decoupling state. If the helical spacing is too small, the helical conformation will be tightly wrapped around the elastomer wire, and eventually a strong coupling state will be generated between the helical conformation and the elastomer wire. After stretching, it will not easily return to its original length.

[0014] As a preferred technical solution:

[0015] As described above, the diameter of the stretchable conductive signal wire is ≤1.5mm. If the wire diameter is too thick, it will affect the softness and comfort of the clothing. If the wire diameter is too thin, it will affect the overall tensile performance of the stretchable signal wire and reduce its tensile strength.

[0016] As described above, a stretchable conductive signal wire, the pre-stretched elastomer wire refers to an elastomer wire that is pre-stretched by 10-20%.

[0017] The stretchable conductive signal line described above has an elongation rate of 71% or more and a tensile strength of 10N or more.

[0018] After being placed in an environment with a temperature of 25℃ and relative humidity of 65% and 35% for 1000 hours, the stretchable conductive signal line was stretched to a certain length, and the resistance change rate did not exceed 0.2%.

[0019] After being placed in an environment with a temperature of 45℃ and relative humidity of 65% and 35% for 1000 hours, the stretchable conductive signal line was stretched to a certain length, and the resistance change rate did not exceed 0.2%.

[0020] Under room temperature and relative humidity of 40%, the stretchable conductive signal wire was subjected to 1000 tensile cycles. Each time the same length was stretched, the elastic recovery elongation change rate of the stretchable conductive signal wire did not exceed 0.05%, and the resistance change rate did not exceed 0.1%.

[0021] The stretchable conductive signal wires were all within the stretching range of 80% to 95% during the above tests.

[0022] As described above, a stretchable conductive signal line has an elastic layer consisting of one or more strands of solid tubular elastic wire, and a conductive layer consisting of one or more strands of conductive wire.

[0023] As described above, the elastic layer and the insulating layer are made of one of the following materials: neoprene rubber, nitrile rubber, latex, polyurethane, polypropylene (PP), polyethylene (PE), spandex, and spandex cotton; the conductive layer is made of a metal-based conductive material.

[0024] Elastomer wires are composed of long-chain polymers with a molecular structure that is highly elastic and flexible. These polymer chains can deform under external forces, such as stretching or compression, but will quickly return to their original shape and size after the external force is removed. This molecular structure gives these materials good elasticity, enabling them to quickly return to their initial state after deformation, thus achieving elasticity and flexibility.

[0025] The insulating layer and the elastic layer can be made of the same material and have similar elastic moduli (although they are the same polymer, the processing of the polymer during the molding process is different, so even if they are the same polymer, their elastic moduli are unlikely to be completely consistent) to ensure that the insulating layer will not easily fall off when the signal line is stretched, twisted or other operations; the insulating layer has high resistance and can effectively prevent the corrosion of the conductive layer by factors such as moisture or dust in the external environment.

[0026] Metal-based conductive wires possess excellent conductivity, effectively transmitting current and electrical signals to ensure stable circuit operation and accurate data transmission; they exhibit high mechanical strength and durability, withstanding significant tensile and compressive forces, making them suitable for various environments and applications; they possess a degree of flexibility, allowing them to be bent and tightly coiled to adhere to elastomer wires; and they have good connectivity, enabling them to be securely connected to various joints and connectors, ensuring reliable circuit connections and signal transmission.

[0027] Metal-based conductive materials include copper, phosphor bronze, tin-plated copper, silver-plated copper, or aluminum.

[0028] The thickness of the insulating layer in the stretchable conductive signal line described above is 30–100 μm.

[0029] The present invention also provides a method for preparing a stretchable conductive signal line as described in any of the preceding claims. First, a conductive wire is wound around the outer wall of a pre-stretched elastomer wire in a spiral rotation manner to obtain a composite wire. Then, an insulating layer is woven into the outer wall of the composite wire to form an insulating layer, or the composite wire is immersed in an insulating layer solution, taken out and dried (drying temperature is 60°C, drying time is 30 min), and an insulating layer is formed on the outer wall of the composite wire to obtain a stretchable conductive signal line.

[0030] The concentration of the insulating layer solution is 30–45 wt%.

[0031] As a preferred technical solution:

[0032] In the method for preparing a stretchable conductive signal line as described above, the spiral rotation speed of the conductive wire is 1500-4000 rpm, and the wire feeding speed of the elastomer is 10-100 mm / s. The spiral spacing is determined by the wire feeding speed and the spiral winding speed. If the wire feeding speed is too fast, the spiral winding speed is too slow, resulting in an excessively large spiral spacing, and the conductive wire cannot be wound in time and will detach from the elastomer. If the wire feeding speed is too slow, the spiral winding speed is too fast, and the conductive wire is wound too densely, affecting the tensile recovery performance of the signal line.

[0033] The present invention also provides an application of a stretchable conductive signal line as described in any of the preceding claims, for use as a signal connection line for electronic devices in smart clothing.

[0034] Invention principle:

[0035] The stretchable conductive signal wire of the present invention includes an elastic layer, a conductive layer, and an insulating layer. The elastic layer and the conductive layer have two different conformational structures. Specifically, the elastic layer (elastic wire) is characterized by a random coil conformational structure with cross-linking at the molecular chain level. The conductive layer (conductive wire) is wound around the outer wall of the pre-stretched elastic wire in a helical rotation manner, exhibiting a helical conformational structure. After the elastic layer and the conductive layer are wound, the degree of physical interlocking between them is controlled by the diameter of the elastic layer and the helical spacing. The helical spacing is achieved through optimization of equipment parameters. After the elastic layer is pre-stressed, the helical spacing affects its interlocking coupling state with the elastic wire. If the helical spacing is too large, it cannot adhere to the elastic wire, and the helical conformation will detach from the elastic in a relaxed state, which is defined as a decoupling state, preventing the stretching process from being completed. If the helical spacing is too small, the helical conformation will be tightly wound around the elastic wire, ultimately creating a strong coupling state between the helical conformation and the elastic fiber, making it difficult to easily return to its original length after stretching.

[0036] In existing technologies, when the diameter of the conductive wire (conductive layer) increases to over 100 μm, lateral forces are generated at certain locations due to the flexibility and non-uniform geometry of the conductive signal wire. While the presence of these lateral forces does not necessarily lead to macroscopic lateral deformation of the conductive signal wire, the uncontrollable macroscopic lateral deformation that occurs when the lateral force exceeds the critical bending yield force of the conductive signal wire prevents the wire from returning to its original straight configuration. By matching and optimizing the helical spacing parameters with the diameter parameters of the elastomer wire, the magnitude of the lateral force generated by the wound conductive signal wire can be reduced, or the critical bending yield force of the wire can be increased (increasing the critical bending yield force of the wire has the same effect as reducing the magnitude of the lateral force). This controls the degree of physical interlocking and fixation between the two, thus resolving the uncontrolled conformational change behavior of the conductive signal wire during relaxation. Specifically, increasing the diameter of the elastomer wire increases its cross-sectional perimeter and contact area, thereby expanding the distribution range of lateral forces. Optimizing the helical spacing further distributes these forces more evenly, reducing their overall intensity. Larger diameter elastomer wires also provide greater load-bearing capacity, allowing the conductive signal wire to withstand higher tensions and reducing the impact of lateral forces. Furthermore, larger diameter conductive signal wires sacrifice tensile strength for increased stiffness, thus expanding the range of bending yield forces they can withstand. Therefore, controlling the diameter and helical spacing of the elastomer wire in a synergistic manner on the stretchable conductive signal wire maximizes tensile stability.

[0037] The reason for setting the helix pitch of the conductive wire to be ≥50μm and ≤1.5mm, and the diameter of the elastomer wire to be ≥400μm, is that if the diameter of the elastomer wire is <400μm, the tensile properties and tensile strength are unbalanced, and the elastic layer wire is not strong in resisting lateral forces. When the helix pitch exceeds 1.5mm, the stretchability of the composite wire is small, which does not match the stretchable conductor envisioned by this invention. If a conductive wire with a helix pitch <50μm is used, the coil is wound too tightly, generating a large lateral force. Using a thicker elastomer wire can solve this problem, but it will lead to an imbalance between its tensile properties and tensile strength. Although this makes the elastic layer wire stronger in resisting lateral forces, its tensile properties are poor and cannot meet the application requirements of stretchable conductors.

[0038] Beneficial effects:

[0039] (1) The stretchable conductive signal line of the present invention has excellent stretch-recovery stability and stretch-conductivity stability. It can withstand stretching and twisting during clothing wearing and activities, and can still recover to the original stretch length after multiple stretchings without affecting its conductivity and integrity, thus ensuring the stability and reliability of signal transmission.

[0040] (2) The stretchable conductive signal line of the present invention has good durability and can resist the effects of daily wear, washing and environmental factors, thus extending the service life of clothing.

[0041] (3) The present invention provides a method for preparing a stretchable conductive signal line, which improves the tensile strength of the stretchable conductive signal line and is simple in method;

[0042] (4) The application of the stretchable conductive signal line of the present invention can meet the needs of different parts of smart clothing for stretchable conductive signal lines. Attached Figure Description

[0043] Figure 1 This is a schematic diagram of a stretchable conductive signal line structure obtained by the present invention;

[0044] Figure 2 This is a schematic diagram illustrating the stretch-recovery principle of a stretchable conductive signal line obtained by the present invention.

[0045] Among them, 1-elastic layer, 2-conductive layer, 3-composite wire, 4-insulating layer. Detailed Implementation

[0046] The present invention will be further described below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims.

[0047] The testing standards / methods used in this invention are as follows:

[0048] Tensile rate and tensile strength: Tested according to GB / T 1040.2-2022; The tensile rate of the stretchable conductive signal wire was tested using a micro-controlled electronic universal testing machine 2TB (tensile) (WDW3020) under the conditions of relative humidity 40% and temperature 25℃, with an extensometer of 75mm and a beam speed of 30mm / min.

[0049] Static conductivity: Under no external force intervention, the resistance of the stretchable conductive signal line was tested using a DMM6500 digital multimeter with a two-point method. In the specific test, the static resistance values ​​measured at temperatures of 25℃ and 45℃ and relative humidities of 65% and 35% were not significantly different and were within the allowable error range of 1‰.

[0050] Tensile-resistance stability and tensile cycle stability: Under room temperature conditions, the stretchable conductive signal line was subjected to tensile cycle testing using a transverse tensile testing machine; the tensile-resistance stability of the stretchable conductive signal line was tested using a transverse tensile testing machine and a DMM6500 digital multimeter; the tensile frequency was 1000Hz.

[0051] Environmental stability: The stretchable conductive signal line was tested for environmental stability using a constant temperature and humidity chamber. After being placed under fixed temperature and humidity conditions for 1000 hours, its resistance value was tested. The temperatures were 25℃ and 45℃, and the relative humidity was 65% and 35%, respectively.

[0052] In the embodiments and comparative examples of this invention, the elastomer wires and conductive wires are all single strands, unless otherwise specified as being one or more strands.

[0053] Example 1

[0054] A method for fabricating a stretchable conductive signal line, comprising the following steps:

[0055] (1) Preparation of raw materials;

[0056] Elastic layer material: Elastomer wire, i.e., 0.4mm diameter polyurethane wire (manufacturer: Yiwu Lycra Wire Industry Co., Ltd., brand: HCSJX03);

[0057] Conductive layer material: conductive wire, i.e., high-purity copper wire with a diameter of 100μm (manufacturer: Shandong Shuohao Metal Products Co., Ltd., grade: T2 C1100);

[0058] Insulation layer material: water-based polyurethane (manufacturer: Anhui Feimiao Chemical Co., Ltd., grade: FS-2040E);

[0059] (2) The elastomer wire is fed at a speed of 35 mm / s, and the conductive wire is wound clockwise at a rotation speed of 4000 rpm on the outer wall of the pre-stretched 10% elastic layer wire to obtain a composite wire with a spiral pitch of 0.57 mm.

[0060] (3) The composite wire is immersed in an insulating layer solution with a concentration of 40wt%, and after being taken out and dried, an insulating layer with a thickness of 75μm is formed on the outer wall of the composite wire to obtain a stretchable conductive signal wire.

[0061] The final stretchable conductive signal wire had an elongation rate of 124% and a tensile strength of 12N. Its static resistance was 0.58Ω. After 1000 hours of simulated aging at 25℃ and relative humidity of 65% and 35%, the resistances were measured to be 0.73Ω and 0.63Ω, respectively. After 1000 hours of simulated aging at 45℃ and relative humidity of 65% and 35%, the resistances were measured to be 0.61Ω and 0.59Ω, respectively. After 1000 hours of aging at 25℃ and relative humidity of 65% and 35%, the stretchable conductive signal wire was stretched to 100% of its original length. The resistance change rates were 0.11% and 0.13%, respectively. After being placed in an environment with a temperature of 45℃ and relative humidity of 65% and 35% for 1000 hours, the stretchable conductive signal wire was stretched to 100% of its stretch length, and the resistance change rates were 0.09% and 0.12%, respectively. Under the conditions of room temperature and 40% relative humidity, the stretchable conductive signal wire was subjected to 1000 stretching cycles, with each stretching elongation rate of 100%. The maximum and minimum elastic recovery elongation change rates of the stretchable conductive signal wire were 0.03% and 0.02%, respectively, and the maximum and minimum resistance change rates were 0.09% and 0.07%, respectively. The stretchable conductive signal wire is used as a signal connection wire for electronic devices in smart clothing.

[0062] The stretchable conductive signal wire prepared by this invention exhibits excellent tensile cycle stability and tensile-resistance stability. This is due to the effective control of the elastomer wire diameter and the helical spacing in the helical structure, such as... Figures 1-2As shown, the elastic layer 1 and the conductive layer 2 are fixed by physical interlocking controlled by the pre-strain of the elastomer wire. The conductive wire is wound to form a spiral structure, thus forming the composite wire 3. By reasonably controlling the range of the diameter of the elastomer wire and the spiral spacing, the stretchable conductive signal wire has both tensile properties and a certain mechanical strength after it is formed, ensuring that it can remain stable when fixed on the clothing.

[0063] Example 2

[0064] A method for fabricating a stretchable conductive signal line, comprising the following steps:

[0065] (1) Preparation of raw materials;

[0066] Elastic layer material: Elastomer yarn, i.e., latex yarn with a diameter of 0.8mm (manufacturer: Changshu Changruilai Garment Accessories Co., Ltd., brand: 021);

[0067] Conductive layer material: conductive wire, i.e., high-purity copper wire with a diameter of 100μm (manufacturer: Shandong Shuohao Metal Products Co., Ltd., grade: T2 C1100);

[0068] Insulation layer material: water-based polyurethane (manufacturer: Anhui Feimiao Chemical Co., Ltd., grade: FS-2040E);

[0069] (2) The elastomer wire is fed at a speed of 45 mm / s, and the conductive wire is wound clockwise at a rotation speed of 3500 rpm on the outer wall of the pre-stretched 10% elastic layer wire to obtain a composite wire with a spiral pitch of 0.86 mm.

[0070] (3) The composite wire is immersed in an insulating layer solution with a concentration of 40wt%, and after being taken out and dried, an insulating layer with a thickness of 75μm is formed on the outer wall of the composite wire to obtain a stretchable conductive signal wire.

[0071] The final stretchable conductive signal wire had an elongation rate of 87% and a tensile strength of 17 N. Its static resistance was 0.57 Ω. After 1000 hours of simulated aging at 25°C and relative humidity of 65% and 35%, the resistances were measured to be 0.72 Ω and 0.66 Ω, respectively. After 1000 hours of simulated aging at 45°C and relative humidity of 65% and 35%, the resistances were measured to be 0.60 Ω and 0.58 Ω, respectively. After 1000 hours of aging at 25°C and relative humidity of 65% and 35%, the stretchable conductive signal wire was stretched to 80% of its original length. The resistance change rates were 0.16% and 0.13%, respectively. After being placed in an environment with a temperature of 45℃ and relative humidity of 65% and 35% for 1000 hours, the stretchable conductive signal wire was stretched to 80% of its stretch length, and the resistance change rates were 0.12% and 0.13%, respectively. Under the conditions of room temperature and 40% relative humidity, the stretchable conductive signal wire was subjected to 1000 stretching cycles, with an elongation rate of 80% per cycle. The maximum and minimum elastic recovery elongation change rates of the stretchable conductive signal wire were 0.05% and 0.04%, respectively, and the maximum and minimum resistance change rates were 0.09% and 0.06%, respectively. The stretchable conductive signal wire is used as a signal connection wire for electronic devices in smart clothing.

[0072] Example 3

[0073] A method for fabricating a stretchable conductive signal line, comprising the following steps:

[0074] (1) Preparation of raw materials;

[0075] Elastic layer material: Elastomer yarn, i.e., 1mm diameter spandex (manufacturer: Shantou Hongfa Yarn Textile Co., Ltd., grade: 4075W);

[0076] Conductive layer material: conductive wire, i.e., high-purity copper wire with a diameter of 120μm (manufacturer: Shandong Shuohao Metal Products Co., Ltd., grade: T2 C1100);

[0077] Insulation layer material: water-based polyurethane (manufacturer: Anhui Feimiao Chemical Co., Ltd., grade: FS-2040E);

[0078] (2) The elastomer wire is fed at a speed of 55 mm / s, and the conductive wire is wound clockwise at a rotation speed of 3800 rpm on the outer wall of the pre-stretched 10% elastic layer wire to obtain a composite wire with a spiral spacing of 1.1 mm.

[0079] (3) The composite wire is immersed in an insulating layer solution with a concentration of 40wt%, and after being taken out and dried, an insulating layer with a thickness of 75μm is formed on the outer wall of the composite wire to obtain a stretchable conductive signal wire.

[0080] The final stretchable conductive signal wire had an elongation rate of 71% and a tensile strength of 21 N. Its static resistance was 0.58 Ω. After 1000 hours of simulated aging at 25°C and relative humidity of 65% and 35%, the resistances were measured to be 0.63 Ω and 0.60 Ω, respectively. After 1000 hours of simulated aging at 45°C and relative humidity of 65% and 35%, the resistances were measured to be 0.66 Ω and 0.59 Ω, respectively. After 1000 hours of aging at 25°C and relative humidity of 65% and 35%, the stretchable conductive signal wire was stretched to 60% of its original length. The resistance change rates were 0.16% and 0.13%, respectively. After being placed in an environment with a temperature of 45℃ and relative humidity of 65% and 35% for 1000 hours, the stretchable conductive signal wire was stretched to 60% of its stretch length, and the resistance change rates were 0.12% and 0.10%, respectively. Under the conditions of room temperature and 40% relative humidity, the stretchable conductive signal wire was subjected to 1000 stretching cycles, with an elongation rate of 60% per cycle. The maximum and minimum elastic recovery elongation change rates of the stretchable conductive signal wire were 0.05% and 0.03%, respectively, and the minimum and maximum resistance change rates were 0.08% and 0.10%, respectively. The stretchable conductive signal wire is used as a signal connection wire for electronic devices in smart clothing.

[0081] Comparative Example 1

[0082] A method for preparing a stretchable conductive signal line is basically the same as in Example 3, except that the elastomer wire is made of spandex with a diameter of 0.3 mm.

[0083] The final stretchable conductive signal wire had an elongation rate of 83% and a tensile strength of 7 N. Under conditions of room temperature and 40% relative humidity, the stretchable conductive signal wire underwent 1000 tensile cycles, with an elongation rate of 70% per cycle. The maximum and minimum elastic recovery elongation rates of the stretchable conductive signal wire were 11% and 8%, respectively.

[0084] Comparing Example 3 with Comparative Example 1, it can be seen that, without changing other parameters, the smaller the diameter of the elastomer wire, the higher the elongation of the stretchable conductive signal wire and the lower the tensile strength. This is because with the same helical spacing, the same lateral force is generated. However, the smaller the diameter of the elastomer wire, the smaller the lateral force it can resist, the lower the tensile strength, and the better the tensile elongation. This leads to an imbalance between tensile performance and tensile strength. It is also the reason why the tensile cycle stability of composite wires with excessively small elastic wire diameters is poor.

[0085] Example 4

[0086] A method for fabricating a stretchable conductive signal line, comprising the following steps:

[0087] (1) Preparation of raw materials;

[0088] Elastic layer material: Elastomer wire, i.e., 0.4mm diameter polyurethane wire (manufacturer: Yiwu Lycra Wire Industry Co., Ltd., brand: HCSJX03);

[0089] Conductive layer material: conductive wire, i.e., 100μm diameter phosphor bronze wire (manufacturer: Dongguan Baoxiang Metal Materials Co., Ltd., grade: Y2);

[0090] Insulation layer material: water-based polyurethane (manufacturer: Anhui Feimiao Chemical Co., Ltd., grade: FS-2040E);

[0091] (2) The elastomer wire is fed at a speed of 35 mm / s, and the conductive wire is wound clockwise at a rotation speed of 4000 rpm on the outer wall of the pre-stretched 15% elastic layer wire to obtain a composite wire with a spiral pitch of 0.56 mm.

[0092] (3) The composite wire is immersed in an insulating layer solution with a concentration of 40wt%, and after being taken out and dried, an insulating layer with a thickness of 75μm is formed on the outer wall of the composite wire to obtain a stretchable conductive signal wire.

[0093] The final stretchable conductive signal wire had an elongation rate of 121% and a tensile strength of 10N. Its static resistance was 0.43Ω. After 1000 hours of simulated aging at 25℃ and relative humidity of 65% and 35%, the resistances were measured to be 0.53Ω and 0.51Ω, respectively. After 1000 hours of simulated aging at 45℃ and relative humidity of 65% and 35%, the resistances were measured to be 0.48Ω and 0.45Ω, respectively. After 1000 hours of aging at 25℃ and relative humidity of 65% and 35%, the stretchable conductive signal wire was stretched to 100% of its original length. The resistance change rates were 0.12% and 0.13%, respectively. After being placed in an environment with a temperature of 45℃ and relative humidity of 65% and 35% for 1000 hours, the stretchable conductive signal wire was stretched to 100% of its stretch length, and the resistance change rates were 0.11% and 0.10%, respectively. Under the conditions of room temperature and 40% relative humidity, the stretchable conductive signal wire was subjected to 1000 stretching cycles, with each stretching elongation rate of 100%. The maximum and minimum elastic recovery elongation change rates of the stretchable conductive signal wire were 0.03% and 0.02%, respectively, and the maximum and minimum resistance change rates were 0.07% and 0.06%, respectively. The stretchable conductive signal wire is used as a signal connection wire for electronic devices in smart clothing.

[0094] Example 5

[0095] A method for fabricating a stretchable conductive signal line, comprising the following steps:

[0096] (1) Preparation of raw materials;

[0097] Elastic layer material: Elastomer yarn, i.e., 1mm diameter spandex (3 strands wound and twisted) (manufacturer: Shantou Hongfa Yarn Textile Co., Ltd., grade: 4075W);

[0098] Conductive layer material: conductive wire, namely 100μm diameter phosphor bronze wire (2 strands wound and twisted) (manufacturer: Shanghai Binmeng Copper Industry Co., Ltd., a strong supplier, grade: BM2306024065);

[0099] Insulation layer material: Nitrile rubber (manufacturer: Jining Hongming Chemical Reagent Co., Ltd., brand: LNBR);

[0100] (2) The elastomer wire is fed at a speed of 45 mm / s, and the conductive wire is wound clockwise at a rotation speed of 3500 rpm on the outer wall of the pre-stretched 10% elastic layer wire to obtain a composite wire with a spiral spacing of 0.73 mm.

[0101] (3) The composite wire is immersed in an insulating layer solution with a concentration of 40wt%, and after being taken out and dried, an insulating layer with a thickness of 100μm is formed on the outer wall of the composite wire to obtain a stretchable conductive signal wire.

[0102] The final stretchable conductive signal wire had an elongation of 75% and a tensile strength of 18N. Its static resistance was 0.45Ω. After 1000 hours of simulated aging at 25℃ and relative humidity of 65% and 35%, the resistances were measured to be 0.57Ω and 0.54Ω, respectively. After 1000 hours of simulated aging at 45℃ and relative humidity of 65% and 35%, the resistances were measured to be 0.52Ω and 0.47Ω, respectively. After 1000 hours of aging at 25℃ and relative humidity of 65% and 35%, the stretchable conductive signal wire was stretched to 70% of its original length. The resistance change rates were 0.13% and 0.11%, respectively. After being placed in an environment with a temperature of 45℃ and relative humidity of 65% and 35% for 1000 hours, the stretchable conductive signal wire was stretched to 70% of its stretch length, and the resistance change rates were 0.14% and 0.12%, respectively. Under the conditions of room temperature and 40% relative humidity, the stretchable conductive signal wire was subjected to 1000 stretching cycles, with an elongation rate of 70% per cycle. The maximum and minimum elastic recovery elongation change rates of the stretchable conductive signal wire were 0.05% and 0.04%, respectively, and the maximum and minimum resistance change rates were 0.08% and 0.07%, respectively. The stretchable conductive signal wire is used as a signal connection wire for electronic devices in smart clothing.

[0103] Example 6

[0104] A method for fabricating a stretchable conductive signal line, comprising the following steps:

[0105] (1) Preparation of raw materials;

[0106] Elastic layer material: Elastomer wire, i.e., 0.5mm diameter polyurethane wire (manufacturer: Yiwu Lycra Wire Industry Co., Ltd., brand: HCSJX03);

[0107] Conductive layer material: conductive wire, i.e., high-purity copper wire with a diameter of 120μm (manufacturer: Shandong Shuohao Metal Products Co., Ltd., grade: T2 C1100);

[0108] Insulation layer material: water-based polyurethane (manufacturer: Anhui Feimiao Chemical Co., Ltd., brand: peelable resin);

[0109] (2) The elastomer wire is fed at a speed of 100 mm / s, and the conductive wire is wound clockwise at a rotation speed of 1500 rpm on the outer wall of the pre-stretched 10% elastic layer wire to obtain a composite wire with a spiral spacing of 1.5 mm.

[0110] (3) The composite wire is immersed in an insulating layer solution with a concentration of 30wt%, and after being taken out and dried, an insulating layer with a thickness of 40μm is formed on the outer wall of the composite wire to obtain a stretchable conductive signal wire.

[0111] The final stretchable conductive signal wire had an elongation rate of 73% and a tensile strength of 11 N. Its static resistance was 0.48 Ω. After 1000 hours of simulated aging at 25°C and relative humidity of 65% and 35%, the resistances were measured to be 0.49 Ω and 0.48 Ω, respectively. After 1000 hours of simulated aging at 45°C and relative humidity of 65% and 35%, the resistances were measured to be 0.46 Ω and 0.45 Ω, respectively. After 1000 hours of aging at 25°C and relative humidity of 65% and 35%, the stretchable conductive signal wire was stretched to 60% of its original length. The resistance change rates were 0.14% and 0.12%, respectively. After being placed in an environment with a temperature of 45℃ and relative humidity of 65% and 35% for 1000 hours, the stretchable conductive signal wire was stretched to 60% of its stretch length, and the resistance change rates were 0.11% and 0.09%, respectively. Under the conditions of room temperature and relative humidity of 40%, the stretchable conductive signal wire was subjected to 1000 stretching cycles, with an elongation rate of 60% per cycle. The maximum and minimum elastic recovery elongation change rates of the stretchable conductive signal wire were 0.04% and 0.03%, respectively, and the maximum and minimum resistance change rates were 0.07% and 0.05%, respectively. The stretchable conductive signal wire is used as a signal connection wire for electronic devices in smart clothing.

[0112] Comparative Example 2

[0113] A method for preparing a stretchable conductive signal line is basically the same as in Example 6, except that in step (2), the wire feeding speed is controlled to be 100 mm / s and the rotation speed is controlled to be 1200 rpm so that the spiral spacing of the conductive wire is 1.8 mm.

[0114] The final stretchable conductive signal line had an elongation of 64% and a tensile strength of 8N. During the stretching cycle test, it was stretched to 52.6% and subjected to 1000 stretching cycles. It was found that the copper wire broke during the cycle, and the electrical signal was interrupted.

[0115] Comparing Example 6 with Comparative Example 2, it can be seen that, without changing other parameters, the helix spacing affects the tensile elongation, tensile strength, and tensile cycle stability of the composite wire. The larger the helix spacing, the smaller the tensile elongation and tensile strength. The tensile cycle stability deteriorates as the tensile elongation and tensile strength decrease. This is because, within the same stretchable range, i.e., when the diameter of the elastomer wire is the same as the material, the larger the helix spacing, the smaller the distance that the outer spirally wound conductive wire can be stretched. Therefore, the conductive wire is prone to breakage during the cyclic stretching-recovery process.

[0116] Example 7

[0117] A method for fabricating a stretchable conductive signal line, comprising the following steps:

[0118] (1) Preparation of raw materials;

[0119] Elastic layer material: Elastomer wire, i.e., 1.0mm diameter polyurethane wire (manufacturer: Yiwu Lycra Wire Industry Co., Ltd., brand: HCSJX03);

[0120] Conductive layer material: conductive wire, i.e., high-purity copper wire with a diameter of 150μm (manufacturer: Shandong Shuohao Metal Products Co., Ltd., grade: T2 C1100);

[0121] Insulation layer material: water-based polyurethane (manufacturer: Anhui Feimiao Chemical Co., Ltd., grade: FS-T35);

[0122] (2) The elastomer wire is fed at a speed of 10 mm / s, and the conductive wire is wound clockwise at a rotation speed of 4000 rpm on the outer wall of the pre-stretched 15% elastic layer wire to obtain a composite wire with a spiral spacing of 0.10 mm.

[0123] (3) The composite wire is immersed in an insulating layer solution with a concentration of 35wt%, and after being taken out and dried, an insulating layer with a thickness of 60μm is formed on the outer wall of the composite wire to obtain a stretchable conductive signal wire.

[0124] The final stretchable conductive signal wire had an elongation rate of 107% and a tensile strength of 14N. Its static resistance was 0.42Ω. After 1000 hours of simulated aging at 25℃ and relative humidity of 65% and 35%, the resistances were measured to be 0.44Ω and 0.43Ω, respectively. Similarly, after 1000 hours of simulated aging at 45℃ and relative humidity of 65% and 35%, the resistances were also measured to be 0.43Ω and 0.42Ω, respectively. Finally, after 1000 hours of aging at 25℃ and relative humidity of 65% and 35%, the stretchable conductive signal wire was stretched to 90% of its original length. The resistance change rates were 0.13% and 0.10%, respectively. After being placed in an environment with a temperature of 45℃ and relative humidity of 65% and 35% for 1000 hours, the stretchable conductive signal wire was stretched to 90% of its stretch length, and the resistance change rates were 0.14% and 0.12%, respectively. Under the conditions of room temperature and 40% relative humidity, the stretchable conductive signal wire was subjected to 1000 stretching cycles, with an elongation rate of 90% per cycle. The maximum and minimum elastic recovery elongation change rates of the stretchable conductive signal wire were 0.05% and 0.03%, respectively, and the maximum and minimum resistance change rates were 0.08% and 0.06%, respectively. The stretchable conductive signal wire is used as a signal connection wire for electronic devices in smart clothing.

[0125] Example 8

[0126] A method for fabricating a stretchable conductive signal line, comprising the following steps:

[0127] (1) Preparation of raw materials;

[0128] Elastic layer material: Elastomer wire, i.e., 1.5mm diameter polyurethane wire (manufacturer: LUOLANMEI Brand name: luolanmei;

[0129] Conductive layer material: conductive wire, i.e., high-purity copper wire with a diameter of 200μm (manufacturer: Shandong Shuohao Metal Products Co., Ltd., grade: T2 C1100);

[0130] Insulation layer material: water-based polyurethane (manufacturer: Anhui Feimiao Chemical Co., Ltd., grade: FS-2345);

[0131] (2) The elastomer wire is fed at a speed of 25 mm / s, and the conductive wire is wound clockwise at a rotation speed of 3500 rpm on the outer wall of the pre-stretched 20% elastic layer wire to obtain a composite wire with a spiral spacing of 0.53 mm.

[0132] (3) The composite wire is immersed in an insulating layer solution with a concentration of 45wt%, and after being taken out and dried, an insulating layer with a thickness of 80μm is formed on the outer wall of the composite wire to obtain a stretchable conductive signal wire.

[0133] The final stretchable conductive signal wire had an elongation rate of 74% and a tensile strength of 20 N. At 25°C, its static resistance was 0.39 Ω. After 1000 hours of simulated aging at 25°C and relative humidity of 65% and 35%, the resistances were measured to be 0.41 Ω and 0.43 Ω, respectively. Similarly, after 1000 hours of simulated aging at 45°C and relative humidity of 65% and 35%, the resistances were measured to be 0.41 Ω and 0.40 Ω, respectively. Finally, after 1000 hours of aging at 25°C and relative humidity of 65% and 35%, the stretchable conductive signal wire was stretched to 70% of its original length. The resistance change rates were 0.11% and 0.10%, respectively. After being placed in an environment with a temperature of 45℃ and relative humidity of 65% and 35% for 1000 hours, the stretchable conductive signal wire was stretched to 70% of its stretch length, and the resistance change rates were 0.13% and 0.12%, respectively. Under the conditions of room temperature and 40% relative humidity, the stretchable conductive signal wire was subjected to 1000 stretching cycles, with an elongation rate of 70% per cycle. The maximum and minimum elastic recovery elongation change rates of the stretchable conductive signal wire were 0.04% and 0.03%, respectively, and the maximum and minimum resistance change rates were 0.06% and 0.05%, respectively. The stretchable conductive signal wire is used as a signal connection wire for electronic devices in smart clothing.

[0134] Comparative Example 3

[0135] A method for preparing a stretchable conductive signal line is basically the same as in Example 8, except that in step (2), the wire feeding speed is controlled to be 100 mm / s and the rotation speed is 4200 rpm so that the spiral spacing of the conductive wire is 45 μm.

[0136] The final stretchable conductive signal wire had an elongation rate of 81% and a tensile strength of 23 N. At 25°C, its static resistance was 0.41 Ω. After 1000 hours of simulated aging at 25°C and relative humidity of 65% and 35%, the resistances were measured to be 0.45 Ω and 0.43 Ω, respectively. Similarly, after 1000 hours of simulated aging at 45°C and relative humidity of 65% and 35%, the resistances were measured to be 0.45 Ω and 0.44 Ω, respectively. Finally, after 1000 hours of aging at 25°C and relative humidity of 65% and 35%, the stretchable conductive signal wire... When the conductive signal wire is stretched to 76.6% of its elongation, the resistance change rates are 0.13% and 0.11%, respectively. After being placed in an environment with a temperature of 45℃ and relative humidity of 65% and 35% for 1000 hours, the stretchable conductive signal wire is stretched to 76.6% of its elongation, and the resistance change rates are 0.11% and 0.08%, respectively. Under the conditions of room temperature and relative humidity of 40%, the stretchable conductive signal wire is subjected to 1000 stretching cycles. The elongation rate of each stretch is 76.6%. The maximum and minimum elastic recovery elongation change rates of the stretchable conductive signal wire are 23.6% and 21.3%, respectively. After stretching multiple times, the electrical signal disappears and the circuit is broken.

[0137] Comparing Example 8 with Comparative Example 3, it can be seen that Comparative Example 3 has poor stability after stretching and recovery. This is because the helical pitch is too small, resulting in a large lateral force and a smaller upper limit for stretching. Exceeding this upper limit will cause the composite wire to fail to recover to its original length.

[0138] Example 9

[0139] A method for fabricating a stretchable conductive signal line, comprising the following steps:

[0140] (1) Preparation of raw materials;

[0141] Elastic layer material: Elastomer wire, i.e., 1.0mm diameter polyurethane wire (manufacturer: Yiwu Lycra Wire Industry Co., Ltd., brand: HCSJX03);

[0142] Conductive layer material: conductive wire, i.e., high-purity copper wire with a diameter of 100μm (manufacturer: Shandong Shuohao Metal Products Co., Ltd., grade: T2 C1100);

[0143] Insulation layer material: spandex (manufacturer: Shantou Hongfa Yarn Textile Co., Ltd., grade: 4075W);

[0144] (2) The elastomer wire is fed at a speed of 10 mm / s, and the conductive wire is wound in a clockwise direction at a rotation speed of 4000 rpm on the outer wall of the pre-stretched 20% elastic layer wire to obtain a composite wire with a spiral spacing of 50 μm.

[0145] (3) Spandex is braided into a tubular shape and tightly wrapped around the outer wall of the composite wire to form an insulating layer. The thickness of the braided mesh is 100μm, thus producing a stretchable conductive signal wire.

[0146] The final stretchable conductive signal wire had an elongation rate of 173% and a tensile strength of 13N. Its static resistance was 0.54Ω. After 1000 hours of simulated aging at 25℃ and relative humidity of 65% and 35%, the resistances were measured to be 0.69Ω and 0.64Ω, respectively. After 1000 hours of simulated aging at 45℃ and relative humidity of 65% and 35%, the resistances were measured to be 0.65Ω and 0.59Ω, respectively. After 1000 hours of aging at 25℃ and relative humidity of 65% and 35%, the stretchable conductive signal wire was stretched to 150% of its original length. The resistance change rates were 0.15% and 0.12%, respectively. After being placed in an environment with a temperature of 45℃ and relative humidity of 65% and 35% for 1000 hours, the stretchable conductive signal wire was stretched to 150% of its stretch length, and the resistance change rates were 0.12% and 0.09%, respectively. Under the conditions of room temperature and 40% relative humidity, the stretchable conductive signal wire was subjected to 1000 stretching cycles, with an elongation rate of 150% per cycle. The maximum and minimum elastic recovery elongation change rates of the stretchable conductive signal wire were 0.04% and 0.02%, respectively, and the maximum and minimum resistance change rates were 0.08% and 0.07%, respectively. The stretchable conductive signal wire is used as a signal connection wire for electronic devices in smart clothing.

Claims

1. A stretchable conductive signal line, characterized in that: It includes an elastic layer, a conductive layer, and an insulating layer; the elastic layer is composed of elastomer wire, the conductive layer is composed of conductive wire, and the conductive wire is wound in a spiral rotation on the outer wall of the pre-stretched elastomer wire; the insulating layer covers the outer wall of the elastic layer and the conductive layer. The diameter of the conductive wire is ≥100μm; the helix pitch of the conductive wire is ≥50µm and ≤1.5mm; the diameter of the elastomer wire is ≥400µm and ≤1.5mm. Pre-stretched elastomer wire refers to elastomer wire that is pre-stretched by 10-20%. The stretchable conductive signal line has an elongation rate of over 71% and a tensile strength of over 9N; After being placed in an environment with a temperature of 25℃ and relative humidity of 65% and 35% for 1000 hours, the resistance change rate of the stretchable conductive signal wire was not more than 0.2% when stretched to a certain length. After being placed in an environment with a temperature of 45℃ and relative humidity of 65% and 35% for 1000 hours, the resistance change rate of the stretchable conductive signal wire was not more than 0.2% when stretched to a certain length. Under conditions of room temperature and 40% relative humidity, the stretchable conductive signal wire was subjected to 1000 tensile cycles. Each time the same length was stretched, the elastic recovery elongation change rate of the stretchable conductive signal wire did not exceed 0.05%, and the resistance change rate did not exceed 0.1%. The stretchable conductive signal wires were all stretched within the range of 80% to 95% during testing.

2. The stretchable conductive signal line according to claim 1, characterized in that, The elastic layer is one or more strands of solid tubular elastic wire; the conductive layer is one or more strands of conductive wire.

3. A stretchable conductive signal line according to claim 2, characterized in that, The elastic layer and the insulating layer are made of one of the following materials: neoprene rubber, nitrile rubber, latex, polyurethane, polypropylene, polyethylene, spandex, and spandex cotton; the conductive layer is made of a metal-based conductive material. Metal-based conductive materials include copper, phosphor bronze, tin-plated copper, silver-plated copper, or aluminum.

4. A stretchable conductive signal line according to claim 1, characterized in that, The thickness of the insulating layer is 30~100μm.

5. A method for preparing a stretchable conductive signal line as described in any one of claims 1 to 4, characterized in that: First, conductive wires are wound in a spiral rotation around the outer wall of a pre-stretched elastomer wire to obtain a composite wire. Then, an insulating layer is woven into the outer wall of the composite wire, or the composite wire is immersed in an insulating layer solution, and after being taken out and dried, an insulating layer is formed on the outer wall of the composite wire to obtain a stretchable conductive signal wire. The concentration of the insulating layer solution is 30~45wt%.

6. The method for preparing a stretchable conductive signal line according to claim 5, characterized in that, The spiral rotation speed of the conductive wire is 1500~4000rpm, and the wire feeding speed of the elastomer wire is 10~100mm / s.

7. The application of a stretchable conductive signal line as described in any one of claims 1 to 4, characterized in that: Used as a signal connection cable for electronic devices in smart clothing.

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