KR102610658B1 - Conductive substrate having conductive structure using liquid metal and functional clothing including the same - Google Patents

Abstract

A conductive substrate having a conductive structure that electrically connects spaced apart conductive patterns using liquid metal and functional clothing including the same are provided. The conductive substrate includes a fabric base; Conductive patterns disposed on the fabric base and including a first conductive pattern and a second conductive pattern spaced apart from each other; and a liquid metal pattern in contact with the first conductive pattern and the second conductive pattern.

Description

Conductive substrate having a conductive structure using liquid metal and functional clothing including the same {CONDUCTIVE SUBSTRATE HAVING CONDUCTIVE STRUCTURE USING LIQUID METAL AND FUNCTIONAL CLOTHING INCLUDING THE SAME}

The present invention relates to a conductive substrate including a conductive pattern. In detail, it relates to a conductive substrate having a conductive structure that electrically connects spaced apart conductive patterns using liquid metal, and functional clothing including the same.

Recently, there has been active development of technologies such as wearable devices that naturally provide convenience functions in daily life without the user having to hold and manage the electronic device. Electronic devices in the form of glasses, watches, bracelets, rings, etc. are being developed as representative wearable devices.

However, the inconvenience that users must wear with their own will is still a limitation, and for this reason, interest in smart wear, in which clothing or the clothing itself can detect or respond to external signals, is gradually increasing. It is expected that such smart wear can be used to monitor the body's vital signs, check biological status, or detect external environmental factors around the body.

KR 10-2035581 B1 KR 10-1993314 B1

Smart wear is being researched in the direction of integrating various electronic devices, circuit boards, and electrically conductive lines on conventional fabric or fiber-type clothing. At this time, using conductive fibers can be considered as a way to form a conductive line for smart wear.

Meanwhile, in the past, methods such as soldering were mainly used to connect a plurality of electrically conductive lines to each other, or to connect a conductive line to another electronic device or circuit board. However, in the case of conductive fibers, there is a problem in that electrical connection through soldering is difficult.

Accordingly, the problem to be solved by the present invention is to provide a conductive substrate that electrically connects a plurality of conductive patterns on a fabric base to each other without using a soldering process involving high heat.

Another problem to be solved by the present invention is to provide functional clothing using the conductive substrate.

Another problem to be solved by the present invention is to provide a method for manufacturing the conductive substrate.

The problems of the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art from the description below.

A conductive substrate according to an embodiment of the present invention for solving the above problems includes a fabric base; Conductive patterns disposed on the fabric base and including a first conductive pattern and a second conductive pattern spaced apart from each other; and a liquid metal pattern in contact with the first conductive pattern and the second conductive pattern.

At this time, the liquid metal may have a surface tension of 600 mN/m to 700 mN/m.

Additionally, the liquid metal may have a viscosity of 2.2×10 ^-3 Pa·s to 2.5×10 ^-3 Pa·s.

Additionally, the liquid metal may have a density of 5.0 g/cm ³ to 7.0 g/cm ³ .

In some embodiments, the conductive substrate may further include a polymer coating layer disposed between the fabric base and the conductive patterns.

The polymer coating layer may be configured such that the contact angle of the liquid metal pattern forms an acute angle.

In some embodiments, the conductive substrate may further include a sealing layer disposed on the conductive patterns and the liquid metal pattern.

At this time, the sealing layer may contact one or more of the conductive patterns, the liquid metal pattern, and the polymer coating layer.

The first conductive pattern and/or the second conductive pattern may at least partially penetrate the fabric base and the polymer coating layer.

In some embodiments the conductive substrate includes a cover base disposed on the fabric base; And it may further include a frame fixed on the cover base.

The frame may include an electrode that penetrates the cover base and contacts the liquid metal pattern.

The fabric base may have higher air permeability than the cover base, and the cover base may have higher elasticity than the fabric base.

Additionally, the first conductive pattern and the second conductive pattern are spaced apart in the first direction, and the stretch rate of the fabric base in the second direction may be greater than the stretch rate in the first direction.

A method of manufacturing a conductive substrate according to an embodiment of the present invention to solve the above other problems includes preparing a fabric base, placing conductive patterns including a first conductive pattern and a second conductive pattern on the fabric base, and disposing a liquid metal pattern to contact the first conductive pattern and the second conductive pattern.

Forming the liquid metal pattern may include preparing a powder-solid liquid metal in which the liquid metal is encapsulated inside a surface layer, and placing the powder-solid liquid metal on a fabric base.

The method may further include forming a polymer coating layer on the fabric base before disposing the conductive patterns, and forming a sealing layer on the liquid metal pattern after disposing the liquid metal pattern.

Additionally, the method may further include forming a liquefied liquid metal pattern by pressing the powder-solid liquid metal.

Specific details of other embodiments are included in the detailed description.

According to embodiments of the present invention, an excellent conductive structure can be achieved without a soldering process involving high heat by electrically connecting spaced apart conductive patterns using liquid metal that is in a liquid state at room temperature.

Additionally, it can exhibit high durability, stability, and low electrical resistance compared to the case using soldering.

Effects according to embodiments of the present invention are not limited to the contents exemplified above, and further various effects are included in the present specification.

1 is a plan layout of a conductive substrate according to one embodiment of the present invention.
Figure 2 is a cross-sectional view of the conductive substrate of Figure 1.
3 is a plan layout of a conductive substrate according to another embodiment of the present invention.
Figure 4a is a cross-sectional view of the conductive substrate of Figure 3.
Figure 4b is a cross-sectional view of the conductive substrate of Figure 3 cut in another direction.
Figure 5 is a plan layout of a conductive substrate according to another embodiment of the present invention.
Figure 6a is a cross-sectional view of the conductive substrate of Figure 5.
Figure 6b is a cross-sectional view of the conductive substrate of Figure 5 cut in another direction.
Figure 7 is a plan layout of a conductive substrate according to another embodiment of the present invention.
Figure 8 is a cross-sectional view of the conductive substrate of Figure 7.
Figure 9 is a cross-sectional view of a conductive substrate according to another embodiment of the present invention.
Figure 10 is a plan layout of a conductive substrate according to another embodiment of the present invention.
Figures 11 and 12 are images showing the results according to Experimental Example 1.
Figure 13 is an image showing the results according to Experimental Example 2.

The advantages and features of the present invention and methods for achieving them will become clear by referring to the embodiments described in detail below along with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below and will be implemented in various different forms, and only the embodiments serve to ensure that the disclosure of the present invention is complete, and those skilled in the art It is provided to fully inform the person of the scope of the invention, and the present invention is only defined by the scope of the claims. That is, various changes may be made to the embodiments presented by the present invention. The embodiments described below are not intended to limit the embodiments, but should be understood to include all changes, equivalents, and substitutes therefor.

The size, thickness, width, length, etc. of components shown in the drawings may be exaggerated or reduced for convenience and clarity of explanation, so the present invention is not limited to the form shown.

Unless otherwise defined, all terms (including technical and scientific terms) used in this specification may be used with meanings that can be commonly understood by those skilled in the art to which the present invention pertains. Additionally, terms defined in commonly used dictionaries are not interpreted ideally or excessively unless clearly specifically defined.

Spatially relative terms such as 'above', 'upper', 'on', 'below', 'beneath', and 'lower' are used in the drawing. As shown, it can be used to easily describe the correlation between one element or component and other elements or components. Spatially relative terms should be understood as terms that include different directions of the element when used in addition to the direction shown in the drawings. For example, when an element shown in a drawing is turned over, an element described as 'below or beneath' another element may be placed 'above' the other element. Accordingly, the illustrative term 'down' may include both downward and upward directions.

As used herein, 'and/or' includes each and every combination of one or more of the mentioned items. Additionally, the singular form also includes the plural form unless specifically stated in the phrase. As used herein, 'comprises' and/or 'comprising' do not exclude the presence or addition of one or more other components in addition to the mentioned components. The numerical range expressed using 'to' indicates a numerical range that includes the values written before and after it as the lower limit and upper limit, respectively. ‘About’ or ‘approximately’ means a value or numerical range within 20% of the value or numerical range stated thereafter.

In this specification, when referring to components, ordinal modifiers such as 'first component', 'second component', '1-1 component', etc. are used to distinguish one component from another component. It just happens. Accordingly, the first component referred to below may be referred to as the second component within the scope of the technical idea of the present invention. For example, what is referred to as a first component in one embodiment may be referred to as a second component in another embodiment. Also, of course, what is referred to as a first component in the description of the invention may be referred to as a second component in the claims.

In this specification, the first direction (X) refers to any direction, and the second direction (Y) refers to another direction that intersects or is perpendicular to the first direction (X) in a plane. Additionally, the third direction (Z) refers to another direction that intersects or is perpendicular to the plane.

Additionally, the first direction (X) and the second direction (Y) may each be parallel to the horizontal direction, and the third direction (Z) may be parallel to the direction of gravity, but the present invention is not limited thereto.

Unless otherwise defined, 'plane viewpoint' means a viewpoint viewed in a direction perpendicular to and parallel to the plane to which the first direction (X) and the second direction (Y) belong. Additionally, unless otherwise defined, 'overlapping in one direction' means that a plurality of components are overlapped and arranged when viewed in a direction parallel to the one direction.

Unless otherwise defined herein, the term 'fiber' or 'thread' or 'yarn or thread' refers to a natural or artificial long, thin fibrous polymer material, consisting of a single strand or multiple continuous sheets. It can be used to include filaments, which are long fibers, and staples, which are made by twisting short single fibers together.

Additionally, unless otherwise defined, the terms 'conductive yarn', 'conductive yarn', or 'conductive fiber' collectively refer to fiber materials with electrical conductivity, such as a combination of conductive fibers alone, a combination of conductive fibers and non-conductive yarns, or conductive fibers. It can be used to include non-conductive wire plated with a material, etc.

Hereinafter, the present invention will be described in detail with reference to the attached drawings.

1 is a plan layout of a conductive substrate according to one embodiment of the present invention. FIG. 2 is a cross-sectional view of the conductive substrate of FIG. 1 cut in a first direction.

1 and 2, the conductive substrate 11 according to this embodiment includes a base 100 and conductive patterns 210 and 220 disposed on the base 100, and the conductive patterns 210 , 220) may further include a liquid metal pattern 300 in contact with the surface.

Base 100 (or first base) may include a fabric or fiber base. The base may provide a space where conductive patterns 210 and 220, which will be described later, are arranged. The base 100 may include a woven or knitted fabric of fiber yarns. Accordingly, the base 100 can have a certain degree of ventilation and elasticity. The present invention is not limited thereto, but when the electrical connection structure of the conductive substrate 11 or the conductive patterns according to this embodiment is applied to smart wear, etc., the base 100 may correspond to the outer skin, inner skin, or middle skin fabric of clothing. You can.

Conductive patterns 210 and 220 may be fixed on the base 100. The conductive patterns 210 and 220 may include a first conductive pattern 210 and a second conductive pattern 220 . The first conductive pattern 210 and the second conductive pattern 220 may be physically spaced apart from each other and may not be electrically conductive. That is, the first conductive pattern 210 and the second conductive pattern 220 may be in an open state.

The first conductive pattern 210 and the second conductive pattern 220 may be made of the same or different materials. In an example embodiment, the first conductive pattern 210 and/or the second conductive pattern 220 may include conductive yarn. As a specific example, the first conductive pattern 210 and the second conductive pattern 220 may include plated yarn coated with silver (Ag) or copper (Cu) on the surface of synthetic fiber yarn such as nylon or polyurethane. there is. Additionally, when the first conductive pattern 210 and the second conductive pattern 220 include plating yarn, the thickness may be about 100 tex to 150 tex, or about 110 tex to 130 tex.

In some embodiments, the base 100 may have greater elasticity in the second direction (Y) than the elasticity or elasticity rate in the first direction (X). At this time, the first conductive pattern 210 and the second conductive pattern 220 have a portion extending approximately in the first direction (X), and the first conductive pattern 210 and the second conductive pattern 220 are connected to each other. They may be spaced apart in the first direction (X).

One of the technical difficulties in implementing conventional smart wear is a problem due to the elasticity of the clothing fabric, that is, the base 100. Since the base 100 has a certain amount of elasticity, flexibility, and wrinkling properties, it is difficult to arrange the conductive patterns 210 and 220 that provide a conduction path for electrical signals. To solve this problem, conductive yarn can be used as the conductive patterns 210 and 220, but unlike general synthetic fiber yarn, which has high elasticity and flexibility, the conductive yarn has relatively low elasticity. Therefore, the conductive substrate 11 according to the present embodiment controls the extension direction and/or separation direction of the first conductive pattern 210 and the second conductive pattern 220 in consideration of the expansion and contraction direction of the base 100, so as to achieve the above. This may solve the problem somewhat.

The liquid metal pattern 300 may be disposed on the first conductive pattern 210 and the second conductive pattern 220 . For example, the liquid metal pattern 300 is in contact with the first conductive pattern 210 and the second conductive pattern 220, and the first conductive pattern 210 and the second conductive pattern 220 are spaced apart in the first direction (X). It may be placed between the conductive patterns 220. Additionally, the liquid metal pattern 300 may be placed directly on the base 100, or may have a coating layer (not shown) interposed thereto, as will be described later. From a plan view, the liquid metal pattern 300 may have a substantially circular shape, but of course, the present invention is not limited thereto.

As used herein, the term liquid metal may refer to a material containing or substantially consisting of a metal element at, for example, about 25°C. In an exemplary embodiment, the liquid metal pattern 300 may include liquid metal and have a liquid state. In addition, liquid metal forms an oxide film on the surface in contact with oxygen in the air and can maintain its shape in a non-equilibrium state, but in this case, it should also be referred to as a liquid state. That is, an oxide layer may be formed on the surface of the liquid metal pattern 300, but the present invention is not limited thereto.

The liquid metal pattern 300 may include gallium-indium-based liquid metal including gallium (Ga) and indium (In). The physical properties of the liquid metal pattern 300 can be controlled by the composition of gallium and indium and other additives. In an exemplary embodiment, the liquid metal pattern 300 may include a liquid metal composition having a melting point in the range of about 14.0°C to 17.0°C, or about 15.0°C to 16.0°C.

The liquid metal pattern 300 exhibits excellent electrical conductivity and can contact the first conductive pattern 210 and the second conductive pattern 220 to electrically connect them. To this end, the electrical resistance of the liquid metal pattern 300 can be appropriately controlled.

Another technical challenge in implementing conventional smart wear is the problem of electrical connection of conductive patterns, that is, conductors. In particular, when poor connection occurs between a plurality of conductive patterns spaced apart from each other, the essential functions of smart wear become impossible to perform, so the electrical connection of the conductive patterns and their durability can be very important factors.

In the past, methods such as soldering were mainly used to electrically connect evangelists. However, lead (Pb) used in the soldering process has a problem of inferior contact characteristics with silver (Ag) or copper (Cu) coated on the surface of the conductive wire. Therefore, in the electrical connection of conductors coated with silver and/or copper, the soldering process has a very low yield, and even if electrical conduction is achieved, the high electrical resistance at the connection area is a factor that hinders the transmission of sufficient electrical signals. there is a problem.

Additionally, the soldering process has other problems that make it difficult to apply to smart wear. Since the soldering process involves high heat, the heat generated during the soldering process can cause tissue collapse of the base fibers of the conductive yarn, that is, synthetic fibers such as nylon and polyurethane. In other words, there is a problem such as the base fiber inside the silver/copper coating layer being partially melted by heat, which can also lead to problems of lowering the yield and increasing the resistance of the electrical connection of the conductor using the soldering process as described above.

In addition, there is a problem of causing damage to the base 100 when lead, which has a high temperature immediately after melting, comes into contact with the base 100. This not only does not look good, but also causes significant damage depending on the type of fibers constituting the base 100, and in severe cases, it may lead to partial loss of the base 100.

However, when connecting the spaced apart first conductive pattern 210 and second conductive pattern 220 using the liquid metal pattern 300 as in this embodiment, especially when using liquid metal containing gallium and indium, the conductive patterns It has excellent contact characteristics with silver and/or copper and can maintain low electrical resistance at the connection site. This will be described later along with an experimental example.

Additionally, when connected through a soldering process, there is a problem that the connection area is very vulnerable to expansion and contraction. In particular, when the conductive substrate 11 according to this embodiment is applied to clothing, etc., a significant degree of expansion and contraction of the clothing fabric, that is, the base 100, may occur due to the wearer's frequent joint movements. At this time, lead is vulnerable to expansion and contraction, so the connection structure may be damaged as expansion and contraction are repeated. On the other hand, when using the liquid metal pattern 300, there is an advantage that damage is not caused despite stretching because the liquid metal pattern 300 maintains a liquid state that can fluidly change shape at room temperature.

Meanwhile, as described above, the base 100 may include a fabric base having a predetermined air permeability. In the case of the base 100, which is a woven or knitted fabric of fiber yarns, it is porous and has a high surface roughness, so it was confirmed that it is necessary to appropriately control the surface tension, density, etc. of the liquid metal pattern 300, and to complete the present invention. It has arrived.

In an exemplary embodiment, the liquid metal forming the liquid metal pattern 300 may have a surface tension of about 600 mN/m to 700 mN/m. If the surface tension of the liquid metal is too large, the contact angle with the base 100, a coating layer to be described later, or the conductive patterns 210 and 220 may form an obtuse angle. That is, the surface tension or cohesion of the liquid metal is greater than the adhesion with the surface in contact with the liquid metal, and the liquid metal pattern 300 cannot maintain a stable shape. On the other hand, if the surface tension of the liquid metal is too small, problems such as liquid metal, which maintains a liquid state at room temperature, seeps into or penetrates into the porous base 100 may occur.

Additionally, the liquid metal forming the liquid metal pattern 300 may have a viscosity of about 2.2×10 ^-3 Pa·s to 2.5×10 ^-3 Pa·s. If the viscosity of the liquid metal is too low, flowability may be induced in the liquid metal pattern 300, which has a surface tension in the above range, for example, a somewhat lower level than that of normal liquid metal and forms a low contact angle. there is. On the other hand, if the viscosity of the liquid metal is too high, handling the liquid metal may be difficult.

Meanwhile, since the liquid metal has a surface tension and viscosity range in the above-mentioned range, the liquid metal pattern 300 completed by the inventors of the present invention may have a density of about 5.0 g/cm ³ to 7.0 g/cm ³ , the present invention is not limited thereto. As described above, the surface tension, viscosity, and density of the liquid metal forming the liquid metal pattern 300 can be controlled by the composition of the metal forming the liquid metal. As a non-limiting example, the liquid metal may include approximately 73.0 wt% to 74.5 wt% gallium and 25.0 wt% to 27.0 wt% indium.

As described above, the conductive substrate 11 according to the present embodiment can electrically connect the two open conductive patterns 210 and 220 to each other through a method completely different from that of the prior art. Accordingly, excellent electrical conductivity properties can be provided to the conductive substrate 11 including the conductive patterns 210 and 220, and durability of the electrical connection structure can be improved.

In addition, when the conductive substrate 11 according to this embodiment is applied to clothing such as smart wear, the base 100 is a part of the fabric constituting the clothing, as described above. At this time, it is expected that clothing to which the conductive patterns 210 and 220 are applied can be used for special purposes. For example, by providing a measuring device to measure the surrounding environment, such as harmful gases such as VoC, fine dust, pathogens such as viruses, temperature, pH, etc., to protect the wearer or provide information about the surrounding environment to the wearer. It can be used as smart wear for When storing such smart wear, it can be stored in a different way than conventional clothing.

Smart wear using the conductive substrate 11 according to this embodiment has a temperature lower than the melting point of the liquid metal forming the liquid metal pattern 300, for example, about 14.0°C or less, or less than about 14.0°C, or about 13.0°C. It may be stored at a temperature of less than or equal to about 12.0°C, or less than or equal to about 11.0°C, or less than or equal to about 10.0°C, or less than or equal to about 0°C. At a temperature in the above range, the liquid metal pattern 300 can no longer maintain a liquid state and solidifies, enabling more stable storage.

Hereinafter, other embodiments of the present invention will be described. However, the description of the same or extremely similar configuration as the conductive material and/or smart wear using the same according to the above-described embodiments will be omitted, and this will be clearly understood by those skilled in the art from the attached drawings. .

3 is a plan layout of a conductive substrate according to another embodiment of the present invention. FIG. 4A is a cross-sectional view of the conductive substrate of FIG. 3 cut in a first direction. FIG. 4B is a cross-sectional view of the conductive substrate of FIG. 3 cut in another direction, and is a cross-sectional view cut in a second direction.

Referring to FIGS. 3, 4A, and 4B, the conductive substrate 12 according to the present embodiment further includes a polymer coating layer 400 interposed between the liquid metal pattern 300 and the base 100. This is different from the example.

As the polymer coating layer 400 is interposed, the liquid metal pattern 300 may be spaced apart from the base 100 without contacting the base 100 . Additionally, the conductive patterns 210 and 220 may be at least partially spaced apart from the base 100 with the polymer coating layer 400 interposed therebetween. That is, the polymer coating layer 400 may be at least partially interposed between the conductive patterns 210 and 220 and the base 100.

The material of the polymer coating layer 400 may be selected in consideration of the contact angle ( θ ) with the liquid metal forming the liquid metal pattern 300. For example, the polymer coating layer 400 may include a silicone-based polymer, a polyurethane-based polymer, or a mixture thereof. Through this, the contact angle ( θ ) at the edge of the liquid metal pattern 300 in contact with the polymer coating layer 400 can be controlled to form an acute angle, specifically, about 50° or less, or about 40° or less, or about 30° or less. there is. The lower limit of the contact angle ( θ ) is not particularly limited, but may be about 10° or more. Additionally, the polymer coating layer 400 may function as a barrier layer to prevent the liquid metal pattern 300 from penetrating into the base 100.

Meanwhile, the liquid metal pattern 300 may contact both the top surfaces of the conductive patterns 210 and 220 and the top surface of the polymer coating layer 400. At this time, the contact angle formed by the liquid metal pattern 300 on the upper surface of the conductive patterns 210 and 220 may be larger than the contact angle θ formed by the liquid metal pattern 300 on the upper surface of the polymer coating layer 400.

Figure 5 is a plan layout of a conductive substrate according to another embodiment of the present invention. FIG. 6A is a cross-sectional view of the conductive substrate of FIG. 5 cut in a first direction. FIG. 6B is a cross-sectional view of the conductive substrate of FIG. 5 cut in another direction, and is a cross-sectional view cut in a second direction.

Referring to FIGS. 5, 6A, and 6B, the conductive substrate 13 according to this embodiment further includes a sealing layer 500 disposed on the liquid metal pattern 300 and the conductive patterns 210 and 220. This point is different from the embodiment shown in FIG. 3 described above.

The sealing layer 500 may be disposed in contact with the polymer coating layer 400, the conductive patterns 210 and 220, and the liquid metal pattern 300. From a plan view, the size of the sealing layer 500 may be smaller than the size of the polymer coating layer 400 and larger than the size of the liquid metal pattern 300. Additionally, the sealing layer 500 may overlap the base 100, the polymer coating layer 400, the liquid metal pattern 300, and the conductive patterns 210 and 220 in the third direction (Z).

The sealing layer 500 may maintain the shape of the liquid metal pattern 300, which maintains a liquid state at room temperature, and perform the function of preventing flow. The material of the sealing layer 500 is not particularly limited, but may include silicone-based polymer and/or urethane-based polymer in terms of adhesion to the polymer coating layer 400.

Figure 7 is a plan layout of a conductive substrate according to another embodiment of the present invention. FIG. 8 is a cross-sectional view of the conductive substrate of FIG. 7 cut in a first direction.

7 and 8, the conductive substrate 14 according to the present embodiment includes a first conductive pattern 214 and a second conductive pattern 224, and the first conductive pattern 214 and/or the second conductive pattern 224. 2 The difference from the embodiment shown in FIG. 5 is that the conductive pattern 224 extends to penetrate the base 100.

The first conductive pattern 214 may include conductive yarn. At this time, the conductor penetrates the base 100 in the thickness direction, that is, the third direction (Z), and may be located on one side and the other side of the base 100. Accordingly, at some point, for example, from the top of the base 100, the first conductive pattern 214 may be viewed as a plurality of parts spaced apart from each other.

Likewise, the second conductive pattern 224 may include conductive yarn. At this time, the conductor penetrates the base 100 in the thickness direction and may be located on one side and the other side of the base 100. Accordingly, at some point, for example, from the top of the base 100, the second conductive pattern 224 may be viewed as a plurality of parts spaced apart from each other.

Additionally, the first conductive pattern 214 and the second conductive pattern 224 may at least partially penetrate not only the base 100 but also the polymer coating layer 400. Accordingly, in a cross section cut in a certain direction, for example, in a cross section cut in a first direction (X), one side and the other side of a conductive pattern (214, 224) extending in the third direction (Z), And the upper surface can all be in contact with the liquid metal pattern 300.

At this time, the through holes of the base 100 and the polymer coating layer 400, that is, through holes through which the conductive patterns 214 and 224 are inserted, are connected to the liquid metal pattern 300 and the sealing layer 500 and in the third direction ( Z) can be overlapped. Additionally, a plurality of through holes may be arranged to be spaced apart from each other in the first direction (X).

Meanwhile, in this embodiment, the sealing layer 500 may be disposed in contact with the polymer coating layer 400 and the liquid metal pattern 300, but may not be in contact with the conductive patterns 214 and 224. When the sealing layer 500 forms an interface with other components, it is prevented from contacting the conductive patterns 214 and 224, so that all edges of the sealing layer 500 from a planar view are in contact with the polymer coating layer 400. You can. Leakage of the liquid metal pattern 300 can be further prevented by contacting the sealing layer 500 and the polymer coating layer 400, which have a relatively high bonding force, at the peripheral edges.

That is, the advantage is that there are no conductive patterns interposed between the sealing layer 500 and the polymer coating layer 400, and at the same time, the conductive patterns 214 and 224 can be exposed on both one side and the other side of the base 100. There is.

Figure 9 is a cross-sectional view of a conductive substrate according to another embodiment of the present invention, showing a position corresponding to Figure 8, etc.

Referring to FIG. 9, the conductive substrate 15 or smart wear using the same according to the present embodiment further includes a cover base 150 (or second base) and a frame 600, similar to the embodiment of FIG. 7 described above. This is different from the example.

The cover base 150 may be placed on the base 100. The cover base 150 may be in contact with the base 100 or may be partially spaced apart from the base 100. Although the present invention is not limited thereto, the base 100 may correspond to the inner skin or lower layer of clothing, and the cover base 150 may correspond to the outer skin or upper layer of clothing. However, it goes without saying that the present invention is not limited thereto.

The frame 600 may be placed and fixed on the cover base 150. The frame 600 may be provided for fixing another external device, for example, the sensor device 700. That is, the sensor device 700 fixed by the frame 600 may be electrically connected to the conductive substrate 15. To this end, the frame 600 may be provided with fastening means such as slits and protrusions for fixing the sensor device 700 to be attached.

Frame 600 may include electrodes 650. The electrode 650 may be a component for connecting the terminal of the sensor device 700 and the conductive patterns 214 and 224 of the conductive substrate 15. The electrode 650 is partially exposed to the upper part of the frame 600, and the electrode 650 extends approximately in the third direction (Z) and may penetrate the cover base 150 in the third direction (Z). Additionally, the electrode 650 may penetrate the sealing layer 500 and be at least partially inserted into or penetrate the liquid metal pattern 300 to be electrically connected. Accordingly, the first conductive pattern 214 and the second conductive pattern 224 extending approximately in the first direction (X), and the electrode 650 located on top thereof may be electrically connected to each other.

Meanwhile, although the present invention is not limited thereto, the conductive patterns 214 and 224 exposed on the lower surface of the base 100 may be used directly or indirectly to collect the user's biological signals by contacting the user's skin. You can.

In some embodiments, the base 100 may have higher air permeability than the cover base 150, and the cover base 150 may have higher elasticity than the base 100. In this case, the cover base 150 may constitute a fabric layer located outside the base 100. Through this, clothing with improved wearability can be provided. In particular, by fixing the liquid metal pattern 300 to the base 100 located relatively on the inside, the liquid metal pattern 300 can be protected from damage even when large stretching occurs in the conductive substrate 15 due to the movement of the wearer. there is.

Figure 10 is a plan layout of a conductive substrate according to another embodiment of the present invention.

Referring to FIG. 10, the conductive substrate 16 according to this embodiment includes a third conductive pattern 234 and a fourth conductive pattern 244 in addition to the first conductive pattern 214 and the second conductive pattern 224. It is different from the embodiment shown in FIG. 7 in that it further includes a point.

That is, the liquid metal pattern 300 according to this embodiment not only electrically connects the first conductive pattern 214 and the second conductive pattern 224 spaced apart in approximately the first direction (X), but also electrically connects the first conductive pattern 214 and the second conductive pattern 224 in another direction, for example. The third conductive pattern 234 and the fourth conductive pattern 244 extending apart from each other in the second direction (Y) can be electrically connected at once. That is, the liquid metal pattern 300 may function like a node of conductive patterns extending in multiple directions to form an electrical path.

As described above, the conductive substrates according to the present invention can easily connect a plurality of conductive patterns that are open and spaced apart from each other using a liquid metal pattern. The method of manufacturing a conductive substrate according to the present invention includes preparing a base, placing a plurality of conductive patterns including a first conductive pattern and a second conductive pattern on the base, and placing a liquid metal pattern on the base. can do.

In some embodiments, when forming a polymer coating layer, the polymer coating layer may be disposed before the conductive patterns are disposed, and the sealing layer may be disposed after the liquid metal pattern is formed.

Meanwhile, as described above, the liquid metal forming the liquid metal pattern may be difficult to handle because it has a liquid phase at room temperature. To this end, the present invention proposes a method of forming a liquid metal pattern by granulating, solidifying, or powdering the liquid metal.

Specifically, the liquid metal can be converted into particles by ultrasonicating the liquid metal to form a surface oxide film. In this case, the surface oxide film formed is different from the oxide film formed when the liquid metal is exposed to the air, and the ease of handling can be improved by forming the granulated liquid metal in a powder form. In other words, the oxide film formed by natural oxidation in the air maintains a non-equilibrium state, but when slightly shocked or tilted, it immediately liquefies and still maintains flowability. On the other hand, as in the present invention, the granulated powder-solid liquid metal in which a surface oxide film is formed through ultrasonic treatment and the liquid metal is encapsulated therein is liquefied and flows even when a certain impact is applied or tilted. It does not fall and behaves like powder.

Therefore, in the step of forming the liquid metal pattern, the liquid metal pattern (e.g., liquid metal free pattern) can be formed using the powder-solid liquid metal, and then the powder-solid liquid metal can be destroyed and liquefied at an appropriate time. For example, after forming the liquid metal free pattern and sealing the liquid metal free pattern using a sealing layer, the liquid metal free pattern can be pressed to prepare a liquid metal pattern in a liquid state.

Hereinafter, the present invention will be described in more detail with reference to experimental examples.

<Experimental Example 1>

It was placed on a base made of polyester fiber by embroidery using conductive thread. The resistance was measured by connecting a power source to the embroidered conductive thread. The evangelist used Amann's Silver-tech product.

Then, a portion of the conductive wire was cut to form two parts of the conductive wire that were spaced apart from each other and were not conducting, that is, a first conductive pattern and a second conductive pattern.

Next, the two parts of the spaced apart conductor were electrically connected through a soldering process (comparative example), or the two parts of the spaced apart conductor were electrically connected using liquid metal as in the present invention (manufacturing example). The image used in the experiment is shown in Figure 11, and the resistance measurement results are shown in Figure 12.

Referring to Figures 11 and 12, it can be seen that in the initial state, the comparative example shows an electrical resistance of about 76 Ω, and the production example shows an electrical resistance of about 62 Ω. In order to clearly express the resistance behavior in each of the manufacturing examples and comparative examples, the resistance of the conductive wire in the initial state was set differently through intentional control of the experimental conditions. However, it can be confirmed that all the conductive wires before being cut exhibit a certain electrical conductivity. .

And as the conductive thread was cut at around 45 seconds, resistance was not measured in both the manufacturing example and the comparative example.

Next, in the case of the comparative example in which electrical connection was attempted using soldering around 80 seconds, it can be confirmed that resistance measurement was not confirmed again. This may be because the conductor and lead are not electrically connected even though they appear to be in contact, or because the resistance is beyond the allowable measurement range.

On the other hand, in the case of a manufacturing example in which electrical connection was attempted using liquid metal at around 80 seconds, it can be confirmed that the initial level of electrical resistance, that is, electrical resistance of about 62Ω, was recovered.

The inventors of the present invention repeated this experiment 10 times, and when using liquid metal (manufacturing example), normal electrical connection was made all 10 times, but when using a soldering process (comparative example), only 3 out of 10 times. It was confirmed that the yield was only about 30% because resistance was not measured 7 times after the electrical connection was made, and even when the electrical connection was made, it was confirmed that the electrical resistance was significantly higher than the first time.

As a result of analysis to determine why electrical connection is difficult in the case of the soldering process, the nylon used as the base fiber of the conductive yarn was damaged by heat and could not maintain its shape as a fiber yarn, and/or contact between lead and the silver coating layer of the conductive yarn occurred. It is presumed that this is because the characteristics are inferior.

<Experimental Example 2>

Among the comparative examples prepared repeatedly for 10 times in Experimental Example 1 described above, a conductive substrate according to the comparative example with relatively good electrical connection was prepared. Likewise, a conductive substrate was prepared according to the preparation example prepared in Experimental Example 1 described above. That is, a conductive substrate electrically connected using soldering (comparative example) and a conductive substrate electrically connected using liquid metal (production example) were prepared.

Then, the conductive substrates of the comparative and manufacturing examples were repeatedly stretched and contracted in the longitudinal direction of the conductive yarn. The degree of stretching was approximately 10% (initial conductor length 50 mm, maximum extension conductor length 55 mm). Then, the change in resistance of the conductive wire was measured by repeating stretching, and the results are shown in Figure 13.

Referring to FIG. 13, it can be seen that in the manufacturing example, approximately uniform electrical resistance is maintained even when expansion and contraction are repeated 100 times. The change in resistance due to repeated expansion and contraction was about 6%.

On the other hand, in the case of the comparative example, a relatively rapid change in resistance was observed in the initial section up to about 30 times as stretching was repeated. Additionally, damage occurred at the soldering area, i.e. the connection area, around 50 cycles, and resistance measurements were no longer made.

Although the description has been made above with a focus on embodiments of the present invention, this is merely an example and does not limit the present invention, and those skilled in the art will be able to understand the present invention without departing from the essential characteristics of the embodiments of the present invention. It will be apparent that various modifications and applications not exemplified above are possible.

Therefore, the scope of the present invention should be understood to include changes, equivalents, or substitutes of the technical ideas exemplified above. For example, each component specifically shown in the embodiments of the present invention can be modified and implemented. And these variations and differences in application should be construed as being included in the scope of the present invention as defined in the appended claims.

11: Conductive substrate
100: base
210: first conductive pattern
220: second conductive pattern
300: Liquid metal pattern
400: Coating layer
500: sealing layer

Claims (13)

Base;
A polymer coating layer disposed on one surface of the base;
a liquid metal pattern disposed on the polymer coating layer;
a sealing layer disposed on the liquid metal pattern, surrounding the liquid metal pattern in contact with the polymer coating layer, and not in contact with the base;
a first conductive pattern that partially contacts the liquid metal pattern but does not contact the sealing layer; and
A second conductive pattern that is spaced apart from the first conductive pattern and is partially in contact with the liquid metal pattern and electrically connected to the first conductive pattern,
The first conductive pattern at least partially penetrates the base and the polymer coating layer, and the first conductive pattern is at least partially located on the one side and the other side of the base,
The through hole of the base and the polymer coating layer through which the first conductive pattern penetrates overlaps the liquid metal pattern and the sealing layer in the thickness direction. According to paragraph 1,
The liquid metal is,
a surface tension of 600 mN/m to 700 mN/m,
a viscosity of 2.2×10 ^-3 Pa·s to 2.5×10 ^-3 Pa·s, and
A conductive substrate having a density of 5.0 g/cm ³ to 7.0 g/cm ³ . According to paragraph 2,
When viewed in plan, the liquid metal pattern and the polymer coating layer are circular in shape. According to paragraph 3,
From a plan view, the size of the polymer coating layer is larger than the size of the sealing layer,
When viewed in plan, the size of the sealing layer is larger than the size of the liquid metal pattern. According to paragraph 1,
The polymer coating layer is a conductive substrate configured such that the contact angle of the liquid metal pattern forms an acute angle. According to paragraph 1,
The second conductive pattern at least partially penetrates the base and the polymer coating layer, and the second conductive pattern is at least partially located on the one side and the other side of the base,
The through hole of the base and the polymer coating layer through which the second conductive pattern penetrates overlaps the liquid metal pattern and the sealing layer in the thickness direction,
The second conductive pattern is a conductive substrate that does not contact the sealing layer. According to clause 6,
A conductive substrate wherein the first conductive pattern and the second conductive pattern at least partially overlap the sealing layer in a horizontal direction. According to paragraph 1,
a cover base disposed on the base; and
Further comprising a frame fixed on the cover base,
The frame is a conductive substrate including an electrode that penetrates the cover base and contacts the liquid metal pattern. According to clause 8,
The base has a higher air permeability than the cover base,
The cover base is a conductive material having higher elasticity than the base. According to paragraph 1,
The base is a fabric base comprising a woven or knitted fabric of fibrous yarns,
Ends of the first conductive pattern and ends of the second conductive pattern face each other in a first direction, and
A conductive substrate in which the expansion rate of the base in a second direction perpendicular to the first direction is greater than the expansion rate in the first direction. Disposing a polymer coating layer on one side of the base,
A first conductive pattern is disposed to at least partially penetrate the base and the polymer coating layer, and the first conductive pattern is at least partially located on one side and the other side of the base,
A second conductive pattern is disposed to at least partially penetrate the base and the polymer coating layer, and the second conductive pattern is at least partially located on one side and the other side of the base,
On the polymer coating layer, a powder-solid liquid metal with the liquid metal encapsulated inside the surface layer is disposed,
A sealing layer is disposed in contact with the polymer coating layer but not in contact with the base to seal the powder-solid liquid metal,
Forming a liquefied liquid metal pattern by pressing the powder-solid liquid metal sealed by the polymer coating layer and the sealing layer,
The through hole of the base and the polymer coating layer through which the first conductive pattern passes overlaps the liquid metal pattern and the sealing layer in the stacking direction,
A method of manufacturing a conductive substrate, wherein the first conductive pattern does not contact the sealing layer. According to clause 11,
Ends of the first conductive pattern and ends of the second conductive pattern face each other in a first direction,
A method of manufacturing a conductive substrate in which the expansion rate of the base in a second direction perpendicular to the first direction is greater than the expansion rate in the first direction. delete