TWI791320B - Multi-layered asymmetric conductive fabric tape and preparation method thereof - Google Patents

Abstract

Provided are a multi-layered asymmetric conductive fabric tape and a preparation method thereof. The multi-layered asymmetric conductive fabric tape comprises: a first conductive adhesive layer, which is an anisotropic conductive adhesive layer, comprising first metal conductive particles; a second conductive adhesive layer, which is an isotropic conductive adhesive layer, comprising second metal conductive particles; and a conductive fabric layer located between the first conductive adhesive layer and the second conductive adhesive layer, wherein the conductive fabric layer has pores or interstices and at least part of the first and second metal conductive particles contact each other through the pores or interstices. The multi-layered asymmetric conductive fabric tape of the present disclosure can achieve great conduction performance in the case that the ground hole is small, be suitable for a vacuum press process, and has excellent air permeability, peelability and adhesion.

Description

A kind of multi-layer asymmetric conductive cloth tape and preparation method thereof

The present disclosure relates to flexible printed circuit (FPC), in particular to multi-layer asymmetrical conductive cloth tape.

The development trend of electronic and communication products requires the development of flexible printed circuit (FPC) components towards thinner, smaller and higher integration. FPC needs to be laminated with conductive adhesive and its reinforcing structure after going through multiple processes. At present, the conductive adhesive products commonly used in the market have the problem of strong bonding force with FPC material but insufficient bonding force with steel sheet, or the bonding force with steel sheet The problem of strong but insufficient bonding force with FPC materials, it is difficult to meet the requirements of both strong bonding force at the same time, resulting in the risk that the steel sheet is easy to fall off or the steel sheet and the conductive adhesive will fall off the FPC in the downstream process. , causing the entire FPC to be scrapped.

In addition, the current FPC manufacturing process is gradually improving, requiring the grounding aperture to be smaller and smaller, and also has new requirements for the grounding reliability of circuit components in electronic products. However, due to the fluidity of the adhesive itself, the conduction effect of the conductive adhesive material on extremely small apertures is not ideal, and there will be a situation where the conduction resistance is large, and the resistance after the surface mount technology (SMT) process The value also increases. Although there are some new technologies that use the piercing effect of large-particle metal powder to solve this problem and even avoid hole design, it is found in practice that this material is expensive and difficult to promote on a large scale. It can only be applied to some high-end products. In addition, due to the large particle size of the conductive particles in the production process, the finished product is required to be thin, making it difficult to guarantee the actual production process and yield.

Furthermore, the current conductive adhesive products developed by the industry are generally only suitable for the pressure transmission and general fast pressing process of FPC factories. However, due to the increasingly stringent requirements for dimensional stability and appearance of FPC boards, general fast pressing will affect the appearance of FPC boards. , The pressure transmission has a great influence on the dimensional stability of the FPC board, so each FPC factory turns to promote the new process of vacuum fast pressing, which can reduce the impact on the appearance and size safety during the pressing process through the buffering effect of the vacuum air bag. However, the fast vacuum pressing is limited by the pressure, which leads to the problem of unstable or insufficient conductivity of conductive adhesive products when using this pressing method. Therefore, it is urgent to develop a new material.

0.4mm)的情況下獲得優異的導通效果，同時亦可遮蔽外來信號的干擾。而且，在與鋼片等貼合後組成加強部件也可有效防止安裝部位出現變形，並因鋼片挺性較佳而利於FPC零部件安裝搬運等操作。再者，本發明通過同向型與異向型導電黏著劑層的結合及不對稱型結構設計，可在傳壓、一般快壓及真空快壓條件下都獲得較好的小孔徑導通效果，有效解決真空快壓小孔徑導通性不穩或者不足的問題。 The technical problem mainly solved by this disclosure is to provide a multi-layer asymmetric conductive cloth tape and its preparation method. The combination of the upper and lower layers of different directional conductive adhesive layers and the combination effect of the metal particles of different shapes and particle sizes contained in it, so that the grounding hole in the FPC is very small (

0.4mm) to obtain excellent conduction effect, but also shield the interference of external signals. Moreover, forming a reinforcing part after being bonded with a steel sheet can also effectively prevent deformation of the installation part, and because the steel sheet has better stiffness, it is beneficial to operations such as installation and handling of FPC parts. Furthermore, the present invention can obtain better small-aperture conduction effects under the conditions of pressure transmission, general fast pressure and vacuum fast pressure through the combination of the same direction type and the anisotropy type conductive adhesive layer and the design of the asymmetric structure. Effectively solve the problem of unstable or insufficient conductivity of the small aperture of the vacuum fast pressure.

In view of this, the present disclosure provides a multi-layer asymmetric conductive cloth tape, including:

The first conductive adhesive layer is an anisotropic conductive adhesive layer, including first metal conductive particles;

The second conductive adhesive layer is an isotropic conductive adhesive layer, including second metal conductive particles; and

The conductive cloth layer is located between the first conductive adhesive layer and the second conductive adhesive layer, wherein the conductive cloth layer has holes or gaps, and at least part of the first metal conductive particles and the second metal conductive The particles contact each other through the pores or interstices.

In a specific embodiment, the shape of the first conductive metal particle is at least one selected from the group consisting of dendrite, needle, flake and spherical.

In a specific embodiment, the shape of the second conductive metal particle is at least two selected from the group consisting of dendrite, needle, flake and spherical.

In a specific implementation mode, the shape of the first conductive metal particle includes a dendritic shape, the shape of the second conductive metal particle includes a sheet shape and a dendritic shape, and the sheet-shaped conductive metal particles in the second conductive metal particle and The weight ratio of the dendritic metal conductive particles is 1:2 to 1:4.

In a specific implementation aspect, the particle diameter D90 of the first conductive metal particle is greater than the particle diameter D90 of the second conductive metal particle.

In a specific embodiment, the particle size of the first conductive metal particles is 25 μm to 55 μm, and the particle size of the second conductive metal particles is 10 μm to 15 μm.

In a specific embodiment, the first conductive adhesive layer and the second conductive adhesive layer are thermosetting adhesive layers including an adhesive resin, and the content ratio of the second metal conductive particles in the second conductive adhesive layer is higher than the content ratio of the first metal conductive particles in the first conductive adhesive layer.

In a specific embodiment, the content ratio of the first metal conductive particles in the first conductive adhesive layer is 20% to 55% by weight, and the content of the second metal conductive particles in the second conductive adhesive layer The content ratio is 45% by weight to 75% by weight.

In a specific embodiment, the material of the first and second metal conductive particles is selected from the group consisting of gold, silver, copper, nickel, silver-plated copper, silver-plated nickel, gold-plated copper, gold-plated nickel and alloys thereof at least one of them.

In a specific embodiment, the material of the first metal conductive particles is nickel or silver-plated nickel, and the material of the second metal conductive particles is nickel, silver-plated copper, silver-plated nickel or gold-plated copper.

In a specific implementation aspect, the material of the first conductive metal particles is different from the material of the second conductive metal particles.

In a specific implementation aspect, the thickness of the first conductive adhesive layer is greater than the thickness of the second conductive adhesive layer.

In a specific embodiment, the thickness of the first conductive adhesive layer is 35 μm to 50 μm, and the thickness of the second conductive adhesive layer is 10 μm to 25 μm.

In a specific embodiment, the conductive cloth layer is composed of a gray cloth and a metal coating on the surface of the gray cloth. In another specific embodiment, the metal coating is copper-plated nickel layer Cu-Ni, copper-plated cobalt layer Cu-Co, copper-plated tin layer Cu-Sn, copper-plated silver layer Cu-Ag, copper-plated iron-nickel layer Cu-Fe-Ni, copper-plated gold layer Cu-Au or copper-plated layer Cu. In yet another specific implementation aspect, the metal coating is Cu—Ni and Cu—Ag.

The disclosure further provides the method of the multi-layer asymmetric conductive cloth tape, including:

mixing the first metal conductive particles with an adhesive resin to obtain a first conductive adhesive mixture;

mixing the second metal conductive particles with another adhesive resin to obtain a second conductive adhesive mixture;

coating the first conductive adhesive mixture on the surface of the carrier layer to obtain the first conductive adhesive layer;

attaching the first conductive adhesive layer on the surface of the conductive cloth layer;

coating the second conductive adhesive mixture on the surface of another carrier layer to obtain the second conductive adhesive layer; and

The second conductive adhesive layer is pasted on the other surface of the conductive cloth layer.

The beneficial effects of the present disclosure have at least the following points:

0.4mm)的情況下具有良好的導通性能；同時因第二導電黏著劑層中的第二金屬導電粒子的粒徑較小，經壓合後不會造成FPC表面的其他材料層被破壞或有顆粒點凸出，對FPC板材起到保護作用； 1. After the FPC high-temperature pressing process, the large-grained first metal conductive particles in the first conductive adhesive layer can contact the second metal conductive particles in the lower layer through the holes or gaps in the conductive cloth layer, and the second metal conductive particles are in contact with the second metal conductive particles. Ground hole contact can be reached in ground holes that are small (

0.4mm) has good conduction performance; at the same time, because the particle size of the second metal conductive particles in the second conductive adhesive layer is small, it will not cause damage or damage to other material layers on the surface of the FPC after lamination. The particle points are protruding, which protects the FPC sheet;

2. In the conductive cloth tape of the present disclosure, the thickness of the first conductive adhesive layer is 35 μm to 50 μm, the thickness of the second conductive adhesive layer is 10 μm to 25 μm, the first and second conductive adhesive layers and the conductive cloth layer The total thickness is between 45 μm and 60 μm. In actual production, because the conductive cloth layer has a mesh or fibrous structure, the first and second conductive adhesives will penetrate into the holes of the conductive cloth layer, so the actual total thickness will be smaller than the conductive cloth layer and the first and second conductive adhesives. The sum of the thicknesses of the conductive adhesive layer is generally equivalent to the sum of the thicknesses of the first and second conductive adhesive layers. And the thickness will be further reduced after lamination. For example, the thickness of the finished conductive cloth tape is 60 μm, and the thickness after lamination is only about 42 μm to 45 μm;

3. This disclosure, through the combination of the same direction type and the opposite direction type conductive adhesive and the asymmetric structure design, can obtain better performance in the downstream FPC process, no matter under the conditions of pressure transmission, general fast pressure, or vacuum fast pressure. Small aperture conduction effect, effectively solving the problem of unstable or insufficient vacuum fast pressure small aperture conduction;

0.4mm)導通性及穩定性不足的缺陷；另一方面，可通過上下層厚度及生產工藝參數的調節，使得該導電布 膠帶之上下層分別與鋼片和FPC結合並經FPC壓合熟化工藝後，於進行剝離測試時的破壞介面會出現在中間的導電布層，不會出現單純導電膠層與FPC或者鋼片結合力不足的問題，大大減少FPC加強零部件在搬運、移動或者運輸過程中脫落的狀況； 4. When the conductive cloth tape disclosed in this disclosure is used, the conductive cloth layer is thin and has good flexibility. After the conductive cloth tape is combined with the steel sheet and undergoes a downstream pressing process, the metal conductive particles in the conductive adhesive layer will pass through the conductive cloth. The holes or gaps in the cloth are used to realize the connection of the upper and lower conductive particles and the adhesive, and because the content of the lower layer of metal conductive particles is relatively high, the probability of metal conductive particles contacting the FPC surface is greatly increased, which can effectively solve the problem encountered in the FPC process. extremely small aperture (

0.4mm) conductivity and insufficient stability; on the other hand, through the adjustment of the thickness of the upper and lower layers and the production process parameters, the upper and lower layers of the conductive cloth tape are respectively combined with the steel sheet and the FPC and subjected to the FPC pressing and curing process Finally, the damaged interface during the peel test will appear in the middle conductive cloth layer, and there will be no problem of insufficient bonding force between the simple conductive adhesive layer and the FPC or steel sheet, which greatly reduces the handling, moving or transportation of FPC reinforced parts. The state of falling out;

5. The conductive cloth layer of this disclosure uses fiber cloth as the base material, which has good flexibility and wear resistance, and is soft in texture. There will be no pauses when peeling off, and the overall continuity can be broken. The design of the intermediate conductive cloth layer has greatly improved the problems of insufficient peelability and insufficient adhesion of the current conductive adhesives in the FPC manufacturing process on the market, which make the FPC easy to fall off;

6. The conductive cloth layer of this disclosure is beneficial to the connection between the upper and lower conductive adhesive layers and metal conductive particles through the holes or gaps in the upper and lower layers because of its fibrous or mesh structure, and because of its good air permeability, so In the downstream process of FPC, there will be no board explosion after SMT, which can effectively solve the problem of board explosion after SMT encountered by conductive adhesives currently in the market.

100: conductive cloth layer

200: first conductive adhesive layer

300: second conductive adhesive layer

400: carrier layer

FIG. 1 is a structural schematic diagram of an embodiment of the disclosed multi-layer asymmetric conductive cloth tape.

The implementation of the present disclosure is described below through specific specific examples, and those skilled in the art to which the present disclosure pertains can easily understand the scope and effect of the present disclosure according to the contents described herein. However, the specific embodiments described herein are not intended to limit the present disclosure, and the listed technical features or solutions can be combined with each other, and the present disclosure can also be implemented or applied through other different implementation modes. The details can also be changed or modified according to different viewpoints and applications without departing from the present disclosure.

It should be noted that the structures, proportions, sizes, etc. shown in the drawings attached to this specification are only used to match the content disclosed in the specification for the understanding and reading of those who are familiar with this technology, and are not used to limit the implementation of this disclosure Therefore, it has no technical substantive meaning. Any modification of structure, change of proportional relationship or adjustment of size shall still fall within the scope of this disclosure without affecting the effect and purpose of this disclosure. The disclosed technical content must be within the scope covered. At the same time, terms such as "above", "first", and "second" quoted in this specification are only for the convenience of description, and are not used to limit the scope of implementation of this disclosure. Changes or adjustments should also be considered as the scope of this disclosure that can be implemented without substantive changes in technical content.

When "includes", "includes" or "has" specific elements in this article, unless otherwise specified, other elements, components, structures, regions, locations, devices, systems, steps, or connection relationships may also be included , not to the exclusion of those other elements.

Unless otherwise clearly stated herein, the singular forms "a" and "the" herein also include plural forms, and the "or" and "and/or" herein may be used interchangeably.

The numerical ranges herein are inclusive and combinable, and any numerical value falling within the numerical range herein can be used as the maximum or minimum value to derive the next range; for example, the numerical range of "25 μm to 55 μm" should be It is understood to include any sub-range between the minimum value of 25 μm and the maximum value of 55 μm, for example: 30 μm to 55 μm, 25 μm to 50 μm, and 30 μm to 50 μm. In addition, if a value falls within the various ranges mentioned herein (eg, between the maximum value and the minimum value), it should be deemed to be included in the scope of the present disclosure.

The multi-layer asymmetric conductive cloth tape of the present disclosure includes: a first conductive adhesive layer, a second conductive adhesive layer and a conductive cloth layer, the conductive cloth layer is located between the first conductive adhesive layer and the second conductive adhesive Between layers, wherein, the first conductive adhesive layer includes first metal conductive particles, the second conductive adhesive layer includes second metal conductive particles, and the conductive cloth layer has holes or voids, which allow at least Parts of the first and second conductive metal particles are in contact with each other. The specific structure of the multi-layer asymmetric conductive cloth can be shown in FIG. 1 . The multi-layer asymmetric conductive cloth tape includes a first conductive adhesive layer 200 , a second conductive adhesive layer 300 and a conductive cloth layer 100 .

In a specific embodiment, the first conductive adhesive layer is an anisotropic conductive adhesive layer; the second conductive adhesive layer is an isotropic conductive adhesive layer, both of which are different types.

In this disclosure, the shape of the first metal conductive particles in the first conductive adhesive layer is at least one selected from the group consisting of dendrites, needles, flakes, and spheres; the shape of the second metal conductive particles is selected from At least two of the group consisting of dendrites, needles, flakes, and spheres.

In a specific embodiment, the shape of the first metal conductive particles is dendritic, which can ensure the conduction of the metal conductive particles in the vertical direction of the conductive cloth tape.

In a specific embodiment, the shape of the second metal conductive particles is flake and dendritic, and the weight ratio of the flake metal conductive particles to the dendritic metal conductive particles is 1:2 to 1:4, ensuring metal conduction The particles have good conduction in the vertical direction of the conductive cloth tape.

In a specific implementation aspect, the particle size of the first conductive metal particles is larger than that of the second conductive metal particles.

For example, the particle size of the first conductive metal particles may be 25 μm to 55 μm, such as 25, 26, 27, 28, 29, 30, 32.5, 35, 37.5, 40, 42.5, 45, 47.5, 50, 52.5 or 55 μm . If the particle size of the metal conductive particles is too large (assessed by D90), it may cause problems with the scraper during the coating process; if the particle size of the metal conductive particles is too small, the probability of connection and contact between the upper and lower conductive adhesive layers may be small, and conduction may occur. Resistance stability is not good.

The particle size of the second metal conductive particles may be 10 μm to 15 μm, for example, 10, 11, 12, 13, 14 or 15 μm. If the particle size of the metal conductive particles is too large, it may lead to the problem of the squeegee coating head during the production process, which may cause the problem of the squeegee coating head during the coating process; if the particle size of the metal conductive particles is too small, it may cause the possibility of connecting the upper and lower conductive adhesive layers. Smaller, the on-resistance stability is not good.

In a specific implementation, the first and second conductive adhesive layers are thermosetting adhesive layers including adhesive resin and metal conductive particles. In a specific implementation aspect, the content ratio of the second metal conductive particles in the second conductive adhesive layer is higher than the content ratio of the first metal conductive particles in the first conductive adhesive layer.

For example, the content ratio of the first metal conductive particles in the first conductive adhesive layer is 20% by weight to 55% by weight, 30% by weight to 50% by weight, or 35% by weight to 50% by weight, such as 20, 22.5 , 25, 27.5, 30, 32.5, 35, 37.5, 40, 42.5, 45, 47.5, 50, 52.5 or 55% by weight. If the content ratio of the metal conductive particles is too high, the powder may be too much, resulting in waste; if the content ratio of the metal conductive particles is too low, the conduction effect may be poor.

The content ratio of the second metal conductive particles in the second conductive adhesive layer is 45% by weight to 75% by weight, 50% by weight to 70% by weight, or 55% by weight to 70% by weight, for example 45, 47.5, 50, 52.5 , 55, 57.5, 60, 62.5, 65, 67.5, 70, 72.5 or 75% by weight, the size and shape of the second metal conductive particles are different from the first metal conductive particles, so as to enhance the conduction effect.

The adhesive resin can be selected from epoxy resin, acrylic resin, urethane resin, silicone rubber resin, parylene resin, bismaleimide resin, phenol resin, melamine resin and Polyimide resin constitutes at least one of the group. In a specific embodiment, the adhesive resin is an acrylic resin. In the present disclosure, the first and second conductive adhesive layers generally use the same adhesive resin to avoid incompatibility problems caused by different adhesive systems.

The material of the first and second metal conductive particles is at least one selected from the group consisting of gold, silver, copper, nickel, silver-plated copper, silver-plated nickel, gold-plated copper, gold-plated nickel and alloys, or the aforementioned materials and graphite and other conductive compounds for further mixing.

In a specific embodiment, the material of the first metal conductive particles is nickel or silver-plated nickel, and the material of the second metal conductive particles is nickel, silver-plated nickel, silver-plated copper or gold-plated copper.

In a specific implementation aspect, the material of the first conductive metal particles is different from the material of the second conductive metal particles. The materials of the second metal conductive particles and the first metal conductive particles are also different, which can further enhance the conduction effect.

In a specific implementation aspect, the thickness of the first conductive adhesive layer is greater than the thickness of the second conductive adhesive layer.

For example, the thickness of the first conductive adhesive layer may be 35 μm to 50 μm, such as 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49 or 50 μm. , and the thickness of the second conductive adhesive layer may be 10 μm to 25 μm, such as 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24 or 25 μm.

In the multi-layer asymmetric conductive fabric tape of the present disclosure, the thickness of the conductive fabric layer may be 5 μm to 15 μm, such as 5, 6, 7, 8, 9, 10, 11, 12, 13, 14 or 15 μm. If the conductive fabric layer is too thick, the metal conductive particles in the first and second conductive adhesive layers may not be in contact or may be in poor contact; if it is too thin, it may be unfavorable to production and increase production cost.

In a specific embodiment, the conductive cloth layer is composed of a gray cloth and a metal coating on the surface of the gray cloth, and the metal coating can be formed on the surface of the conductive cloth layer through an electroplating process. When the metal conductive particles in the conductive adhesive layer are in contact with each other through the holes or gaps in the conductive cloth layer to achieve conduction, the metal plating layer can further ensure the conduction effect.

The metal plating layer can be a copper-nickel layer, a copper-cobalt layer, a copper-tin layer, a copper-silver layer, a copper-iron-nickel layer, a copper-gold layer, a copper-gold layer or a copper-plated layer. In a specific embodiment, the metal plating layer is a copper-nickel-plated layer and a copper-silver-plated layer.

In the multi-layer asymmetric conductive cloth adhesive tape disclosed in the present disclosure, the conductive cloth layer has holes or gaps, specifically, fiber cloth can be used, and the fiber cloth is mesh cloth, flat-woven cloth or non-woven cloth, and the fibers can be observed with a microscope. Intricately overlapping to form a fibrous or network structure, and has many holes or voids of different sizes. The size of the holes or voids is not limited, only that the holes or voids are available to It is only necessary for a small part of the first and second conductive metal particles to be in contact with each other, so as to realize the connection between the upper and lower layers. Further, the size of the holes or voids in the fiber cloth can allow at least part of the conductive metal particles in the first and second conductive adhesive layers to pass through. At the same time, due to the good air permeability of the conductive fabric layer, there will be no cracking phenomenon after SMT in the downstream process of FPC, and the solder resistance is good. On the other hand, the conductive cloth layer is based on ultra-thin fiber cloth, which has good flexibility and wear resistance, which can improve product reliability and masking performance, and the texture is soft, so there will be no stuttering when peeling off. The overall continuity can be broken. Through the design of the intermediate conductive layer, this disclosure greatly solves the problems of insufficient peeling force and insufficient adhesion of the current conductive adhesive in the FPC manufacturing process, which cause the FPC to fall off easily.

In a specific embodiment, the multi-layer asymmetric conductive cloth tape of the present disclosure can further include a carrier layer, which can cover the first and second conductive adhesive layers, as shown in Figure 1, the multi-layer asymmetric conductive The cloth tape includes a carrier layer 400 .

In a specific embodiment, the carrier layer can be a release layer or a low-adhesion carrier layer, and its thickness can be 25 μm to 100 μm. In a specific embodiment, the release layer is a release film or a release paper, which can be a PET fluoroplastic release layer, a PET silicon-containing oil release layer, a PET matte release layer, a PE release layer or a PE coated paper layer. In a specific embodiment, the release layer is a double-sided release layer or a single-sided release layer, preferably a double-sided release film layer.

The color of the release film (paper) can be selected from pure white, milky white or transparent color, preferably pure white or milky white, and the white double-sided PET release film is preferred. Digitally controlled automation equipment uses infrared sensing when engraving lines. Since the white color has no problem of reflected light, it can be positioned quickly and accurately. And in manual work, white also has the function of identification, which can prevent artificial leakage and so on. If the release paper is selected, it is required that the release paper and the conductive adhesive layer of the product are well bonded and easy to peel off, and it is sufficient that the release paper does not fall off during transportation and handling.

The present disclosure provides a method for preparing the multi-layer asymmetric conductive cloth tape, comprising the following steps:

uniformly mixing the first metal conductive particles and the adhesive resin to obtain a first conductive adhesive mixture;

uniformly mixing the second metal conductive particles with the adhesive resin to obtain a second conductive adhesive mixture;

coating a first conductive adhesive mixture on the surface of the carrier layer to obtain a first conductive adhesive layer;

Paste the first conductive adhesive layer on the surface of the conductive cloth layer;

coating a second conductive adhesive mixture on the surface of another carrier layer to obtain a second conductive adhesive layer;

attaching a second conductive adhesive layer on the other surface of the conductive cloth layer; and

Curing, winding, and slitting, that is, the finished product of multi-layer asymmetric conductive cloth tape.

Examples and Comparative Examples

The multi-layer asymmetric conductive cloth tape was obtained by the aforementioned preparation method, and the parameters are listed in Table 1. Conduct a conductivity analysis test on the conductive cloth tape after peeling off the upper and lower carrier layers (release layer). The test method is: after the upper and lower conductive adhesive layers respectively cover the nickel-plated steel sheet and the FPC with a small via hole, They were respectively cured by general quick press and vacuum quick press, and the continuity resistance value was tested by Takahashi tester. In addition, commercially available general conductive adhesive products were measured with the same test method as a comparative example. The measurement results of Examples and Comparative Examples are recorded in Table 1 below.

Table 1

0.4mm)條件下確實展現更優異的導電效果，且穩定性及接著強度亦佳。相較之下，一般導電膠產品在小孔徑的條件下，其導通性明顯較差，甚至不導通。 As can be seen from Table 1 above, the asymmetric conductive cloth tape disclosed in this disclosure has small holes (

0.4mm) does show a better conductive effect, and the stability and bonding strength are also good. In contrast, the conductivity of general conductive adhesive products is obviously poor or even non-conductive under the condition of small aperture.

100: conductive cloth layer

200: first conductive adhesive layer

300: second conductive adhesive layer

400: carrier layer

Claims (15)

A multi-layer asymmetric conductive cloth tape, comprising: The first conductive adhesive layer is an anisotropic conductive adhesive layer, including first metal conductive particles; The second conductive adhesive layer is an isotropic conductive adhesive layer, including second metal conductive particles; and The conductive cloth layer is located between the first conductive adhesive layer and the second conductive adhesive layer, wherein the conductive cloth layer has holes or gaps, and at least part of the first metal conductive particles and the second metal conductive The particles contact each other through the pores or interstices. The multi-layer asymmetric conductive cloth tape according to claim 1, wherein the shape of the first metal conductive particles is at least one selected from the group consisting of dendrites, needles, flakes and spheres. The multi-layer asymmetric conductive cloth tape according to claim 1, wherein the shape of the second metal conductive particles is at least two selected from the group consisting of dendrites, needles, flakes and spheres. The multi-layer asymmetric conductive cloth tape as described in Claim 1, wherein the shape of the first metal conductive particle includes dendritic shape, the shape of the second metal conductive particle includes sheet shape and dendritic shape, and the second metal conductive The weight ratio of flake metal conductive particles and dendritic metal conductive particles in the particles is 1:2 to 1:4. The multi-layer asymmetric conductive cloth tape according to claim 1, wherein the particle diameter D90 of the first metal conductive particles is larger than the particle diameter D90 of the second metal conductive particles. The multi-layer asymmetric conductive cloth tape according to claim 5, wherein the particle size of the first metal conductive particles is 25 μm to 55 μm, and the particle size of the second metal conductive particles is 10 μm to 15 μm. The multi-layer asymmetric conductive cloth tape as described in Claim 1, wherein the first conductive adhesive layer and the second conductive adhesive layer are thermosetting adhesive layers comprising an adhesive resin, and the second conductive adhesive layer The content ratio of the second metal conductive particles in the first conductive adhesive layer is higher than the content ratio of the first metal conductive particles in the first conductive adhesive layer. The multi-layer asymmetric conductive cloth tape as described in Claim 7, wherein the content ratio of the first metal conductive particles in the first conductive adhesive layer is 20% by weight to 55% by weight, and the second conductive adhesive The content ratio of the second metal conductive particles in the layer is 45% by weight to 75% by weight. The multi-layer asymmetric conductive cloth tape as described in Claim 1, wherein the material of the first metal conductive particles and the second metal conductive particles is selected from gold, silver, copper, nickel, silver-plated copper, silver-plated nickel, Gold-plated copper, gold-plated nickel and alloys thereof constitute at least one of the group. The multi-layer asymmetric conductive cloth tape as described in claim 9, wherein the material of the first metal conductive particle is nickel or silver-plated nickel, and the material of the second metal conductive particle is nickel, silver-plated copper, silver-plated Nickel or gold-plated copper. The multi-layer asymmetrical conductive cloth tape as claimed in claim 10, wherein the material of the first metal conductive particles is different from the material of the second metal conductive particles. The multi-layer asymmetric conductive cloth tape according to claim 1, wherein the thickness of the first conductive adhesive layer is greater than the thickness of the second conductive adhesive layer. The multi-layer asymmetric conductive cloth tape according to claim 12, wherein the thickness of the first conductive adhesive layer is 35 μm to 50 μm, and the thickness of the second conductive adhesive layer is 10 μm to 25 μm. The multi-layer asymmetrical conductive cloth adhesive tape as claimed in claim 1, wherein the conductive cloth layer is composed of gray cloth and a metal coating on the surface of the gray cloth. A method for preparing the multi-layer asymmetric conductive cloth adhesive tape as described in claim 1, comprising: mixing the first metal conductive particles with an adhesive resin to obtain a first conductive adhesive mixture; mixing the second metal conductive particles with another adhesive resin to obtain a second conductive adhesive mixture; coating the first conductive adhesive mixture on the surface of the carrier layer to obtain the first conductive adhesive layer; attaching the first conductive adhesive layer on the surface of the conductive cloth layer; coating the second conductive adhesive mixture on the surface of another carrier layer to obtain the second conductive adhesive layer; and The second conductive adhesive layer is pasted on the other surface of the conductive cloth layer.

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