TW201811958A - Conductive adhesive tape and manufacturing method thereof capable of achieving the effect of stably increasing the conductivity - Google Patents

Abstract

Disclosed is a conductive adhesive tape, which is formed by sequentially laminating a release type protective layer, an inorganic and organic composite conductive layer, an adhesive glue layer, and a conductive base material layer. The adhesive glue layer is provided with a plurality of conductive particles mixed within adhesive glue, and the inorganic and organic composite conductive layer is provided with an array of through holes, thereby enabling part of the conductive particles to enter the array of through holes by following the adhesive glue. As a result, it is able to solve the problem of unstable conductivity in the prior art, so as to achieve the effect of stably increasing the conductivity.

Description

Conductive tape and preparation method thereof

The present invention relates to a conductive tape and a preparation method thereof, in particular to an inorganic and organic composite conductive layer that is in direct contact with a conductive adherend, and the inorganic and organic composite conductive layer has a through-hole array, so that the adhesive layer has a part The designer who conducts the conductive particles into the through-hole array with the adhesive.

According to the development of the consumer electronics industry, consumer electronics products have increasingly become smaller, lighter and thinner. Under this trend, electronic products are becoming more integrated and smaller. , Power is getting stronger and stronger; therefore, the trend of high power, high integration, and small application space is bringing a series of problems of conduction and radiation interference to consumer electronics products; however, traditional conductive connection schemes such as metal Reeds, wire and cable connections, connectors, etc., because of their large size, require more space, and cannot meet the needs of lightweight and consumer electronics in a small space.

For the second press, conductive tape is widely used in the consumer electronics industry because of its light weight, thin thickness, certain bonding ability and corresponding conductive properties, to achieve the needs of electrostatic grounding and electromagnetic shielding inside electronic products; however, Since the conductive tape is conductive, conductive particles are mixed in a non-conductive pressure-sensitive adhesive. When the non-conductive pressure-sensitive adhesive is bonded to a conductive object, the conductive particles are in contact with the conductive object and between the conductive particles. The current tunnel effect is realized; however, due to the randomness of the probability of contact between the conductive particles on the surface and the conductive object on the conventional conductive tape, the conductive performance of the conventional conductive tape is unstable, and with the use (adhesion) area The reduction (high integration) leads to a decrease in the existence probability of conductive particles that can effectively conduct electricity, which limits the use of conventional conductive tapes in highly integrated, high-power consumer electronics products.

The main purpose of the present invention is to solve the problem of unstable conductive performance in the prior art, and to have the effect of stably improving the conductive performance.

Another object of the present invention is to make preparations faster.

In order to achieve the above-mentioned effect, the structural characteristics of the conductive tape of the present invention are a laminated protective layer, an inorganic and organic composite conductive layer, an adhesive layer, and a conductive substrate layer, which are sequentially laminated in the adhesive. A plurality of conductive particles are mixed, and the inorganic and organic composite conductive layer has a through-hole array, so that some conductive particles enter the through-hole array with the adhesive.

In addition, the inorganic and organic composite conductive layer is silver paste, copper paste, aluminum silver paste, copper paste, indium tin oxide paste, tin antimony paste, graphite paste, graphite paste, graphene paste, or graphene paste. It is formed on the surface of the release protective layer by gravure printing and has a thickness of 2-6 microns. The adhesive layer is a polyacrylate pressure-sensitive adhesive layer with a thickness of 20-60 micrometers, and the conductive particles are conductive particles or / and conductive fibers. The conductive particles are selected from pure nickel powder, nickel-coated graphite powder, nickel-coated mica powder, silver powder, silver-plated mica, silver-plated hollow microspheres, graphite powder, graphene, or conductive carbon black; and the conductive fiber is selected from Nai Rice silver wire, graphite fiber, graphene fiber, carbon fiber, silver-plated glass fiber, nickel-clad carbon fiber or silver-plated carbon fiber. The conductive substrate layer is any one or combination of pure metal foil, metal particles, metal microwires, metal nanowires, graphene, or a porous fiber material with a metal plating layer, and has a thickness of 10-200 microns. The through-hole array is a circular through-hole array, an oval through-hole array, a diamond-shaped through-hole array, a square through-hole array, or a star-shaped through-hole array. The release protective layer is a PET film coated with a release agent on the surface or a paper coated with a release agent on the surface, and has a thickness of 30-150 microns.

Furthermore, the method for preparing a conductive tape of the present invention includes the following steps: Step 1: Applying a composite conductive coating mixed with an inorganic substance and an organic substance on the surface of the release protective layer, and forming an inorganic substance having a through-hole array on the surface of the release protective layer. After the conductive layer is compounded with an organic substance, and the solvent in the conductive coating is baked and expelled, the inorganic and organic compound conductive layer is cured on the surface of the release protective layer; Step 2: Coating the surface of the temporary release protective layer with a plurality of conductive layers After the particle adhesive is baked, the solvent in the adhesive is expelled by baking, so that the adhesive is cured on the surface of the temporary release protective layer to form an adhesive layer, and then the other surface of the adhesive layer is opposite to the temporary release protective layer. A conductive substrate layer; and step three: unload the temporary release protective layer from the product of step two, and then make the inorganic substance with a release protective layer and the other surface of the adhesive layer opposite the temporary conductive substrate layer and step one Organic compound conductive layer is laminated.

In addition, a composite conductive layer of an inorganic substance and an organic substance is produced by gravure printing. The contact surface of the release protective layer with respect to the inorganic and organic composite conductive layer is coated with a release agent in advance, and the contact surface of the temporary release protective layer with the adhesive layer is previously coated with a release agent.

As a result, the present invention adds a conductive layer of inorganic and organic compounds that is in direct contact with the conductive adherend compared to the conventional conductive tape, and the inorganic and organic compound conductive layer has a through-hole array, so that the adhesive layer is partially conductive. The particles enter the through-hole array with the adhesive, and the conductive particles and the conductive adherend are brought into contact from the original plane, and the inorganic and organic composite conductive layers are evolved to form a body contact.

First, please refer to [Fig. 1] to [Fig. 3], the conductive tape of the present invention is sequentially stacked and includes: a release protective layer 10, which can be a PET film or a surface coating coated with a release agent. The release agent paper is 30-150 microns thick; an inorganic and organic composite conductive layer 20 can be silver paste, copper paste, aluminum silver paste, copper paste, indium tin oxide paste, tin antimony paste, Graphite paste, graphite paste, graphene paste, or graphene paste is formed on the surface of the release protective layer 10 by gravure printing and has a through-hole array 21 with a thickness of 2-6 microns. The through-hole array 21 may be circular Through-hole array (as shown in [Figure 3]), oval through-hole array, diamond-shaped through-hole array, square through-hole array (as shown in [Figure 2]) or star-shaped through-hole array; an adhesive layer 30, A plurality of conductive particles 31 are mixed in the adhesive, and some of the conductive particles 31 enter the through-hole array 21 with the adhesive. The adhesive layer 30 may be a polyacrylate pressure-sensitive adhesive layer with a thickness of 20-60 microns. The conductive particles 31 may be selected from pure nickel powder, nickel-coated graphite powder, nickel-coated mica powder, silver powder, and silver-plated cloud. 、 Silver-plated hollow microspheres, graphite powder, graphene or conductive carbon black conductive particles Carbon fiber conductive fibers; and a conductive substrate layer 40, which can be any one or a combination of pure metal foil, metal particles, metal microwires, metal nanowires, graphene, or porous fiber materials with metal plating, and the thickness is 10 -200 microns.

The following further describes the present invention in detail with reference to specific examples, but the scope of the present invention is not limited to the range expressed in the examples. The proportions involved in the examples are weight percentages. The conductive substrates and polymers used are Acrylic resins, solvents, curing agents, conductive particles, conductive fibers, composite conductive coatings of inorganic and organic materials, and release protection materials may be other applicable materials in addition to the materials mentioned.

Example 1 Step 1: Use a conductive silver paste as a conductive coating that mixes inorganic and organic matter. By gravure printing, follow the array pattern of the silver paste in [Fig. 2] with a wire diameter of 0.3mm and a square through hole of 1mm × 1mm and printing thickness of 3 microns, printed on the surface of a PET film with a release silicone oil (release force 8-12g) and a thickness of 75 microns, conveying the PET film (release protective layer) after printing silver paste After entering the oven, the baking temperature is 120 ° C and the baking speed is 200mm / sec. After baking, an inorganic and organic composite conductive layer with a through-hole array is attached to the release PET film. Step 2: Take a polymer acrylic resin as a main body and add ethyl acetate, an isocyanate hardener and a plurality of conductive particles to form a mixture, the weight percentage is: polymer acrylic resin 30% -40%, ethyl acetate 44% -54%, isocyanate Hardener 0.5% -1%, conductive particles 5% -15%, stirred at 1000 rpm for 30 minutes to make a polyacrylate pressure-sensitive adhesive mixture containing a plurality of conductive particles, and then coating the mixture for 30 microns The thickness of a temporary PET release film with a release silicone oil on a surface of 75 microns in thickness is fed into the oven at a speed of 8m / min. After baking, the polyacrylate pressure-sensitive adhesive mixture containing a plurality of conductive particles is cured in the temporary release A polyacrylate pressure-sensitive adhesive layer was formed on the surface of the protective layer, and then a 35-micrometer-thick copper foil substrate (conductive substrate layer) was bonded to the polyacrylate pressure-sensitive adhesive layer. Step 3: Unload the temporary release protective layer from the product in Step 2, and then make the polyacrylate pressure-sensitive adhesive layer opposite to the other surface of the copper foil substrate and step 1 to make the inorganic and organic compounds with a release protective layer conductive. The layers are laminated to form the conductive tape of this embodiment.

Use a multimeter to test the resistance values of Example 1 and the conventional conductive tape (excluding the composite conductive layer of inorganic matter and organic matter). The test results are as follows: According to ASTM D3330, test Example 1 and the conventional conductive tape (excluding inorganic and organic composite conductive layer) to perform 180-degree peeling. The test results are as follows Test results: In Example 1, while ensuring sufficient adhesive strength, the conductive properties of the surface of the conductive tape were effectively improved.

Example 2 Step 1: Use conductive copper paste as a conductive coating that mixes inorganic and organic matter. By gravure printing, follow the array pattern of copper paste in [Fig. 3] with circular hole diameter of 3mm and circular hole spacing of 1mm. The printing thickness is 5 micron. The printing size is printed on the surface of the PET film with a release silicone oil (release force is 8-12g) and a thickness of 75 micron. The PET film (release protective layer) after the silver paste is printed is sent into the surface. In an oven, the baking temperature is 120 ° C. and the baking speed is 200 mm / sec. After the baking is completed, an inorganic and organic composite conductive layer with a through-hole array is attached to the release PET film. Step 2: Take a polymer acrylic resin as a main body and add ethyl acetate, an isocyanate hardener and a plurality of conductive particles to form a mixture, the weight percentage is: polymer acrylic resin 30% -40%, ethyl acetate 44% -54%, isocyanate Hardener 0.5% -1%, conductive particles 5% -15%, stirred at 1000 rpm for 30 minutes to make a polyacrylate pressure-sensitive adhesive mixture containing a plurality of conductive particles, and then coating the mixture for 30 microns The thickness of a temporary PET release film with a release silicone oil on a surface of 75 microns in thickness is fed into the oven at a speed of 8m / min. After baking, the polyacrylate pressure-sensitive adhesive mixture containing a plurality of conductive particles is cured in the temporary release A polyacrylate pressure-sensitive adhesive layer was formed on the surface of the protective layer, and then a 55 micron-thick nickel-plated conductive textile (conductive substrate layer) was bonded to the polyacrylate pressure-sensitive adhesive layer. Step 3: Unload the temporary release protective layer from the product in Step 2, and then place the polyacrylate pressure-sensitive adhesive layer on the other surface of the nickel-plated conductive fabric and step 1 to make an inorganic and organic compound with a release protective layer. Laminating the conductive layers constitutes the conductive tape of this embodiment.

Use a multimeter to test the resistance values of Example 2 and the conventional conductive tape (excluding the composite conductive layer of inorganic matter and organic matter). The test results are as follows: According to ASTM D3330, test Example 1 and the conventional conductive tape (excluding inorganic and organic composite conductive layer) to perform 180-degree peeling. The test results are as follows Test results: Example 2 effectively improved the conductivity of the surface of the conductive tape while ensuring sufficient adhesive strength.

Based on the structure, the above two embodiments can be used to explain that the present invention can be prepared quickly in only three steps. When the present invention is pasted on a conductive adherend that requires a conductive connection, the present invention is more expensive than the conventional conductive tape. The inorganic-organic composite conductive layer 20 is in direct contact with the conductive adherend, and the inorganic-organic composite conductive layer 20 has a through-hole array 21, so that some of the conductive particles 31 of the adhesive layer 30 enter the adhesive layer with the adhesive. In the through-hole array 21, the conductive particles 31 and the conductive adherend are brought into contact from the original plane. The inorganic and organic composite conductive layer 20 has evolved into a body contact type, which improves the contact between the conductive particles 31 and the conductive adherend. The area of total contact (direct contact + indirect contact through the inorganic and organic composite conductive layer 20); therefore, the present invention has the effects of stably improving the conductivity and rapid preparation.

In summary, the technical means disclosed in the present invention do have invention patent elements such as "newness", "progressivity" and "available for industrial use". A sense of virtue.

However, the drawings and descriptions disclosed above are only preferred embodiments of the present invention. Modifications or equivalent changes made by those skilled in the art in accordance with the spirit of this case should still be included in the scope of patent application for this case.

10‧‧‧ Release protective layer

20‧‧‧ Inorganic and organic composite conductive layer

21‧‧‧Through Hole Array

30‧‧‧ Adhesive layer

31‧‧‧ conductive particles

40‧‧‧ conductive substrate layer

[Fig. 1] is a structural sectional view of the present invention. [Fig. 2] It is a schematic diagram of a square through-hole array of an inorganic and organic composite conductive layer of the present invention. [Figure 3] Schematic diagram of a circular through-hole array of an inorganic and organic composite conductive layer of the present invention.

Claims (10)

A conductive tape is a laminated protective layer, an inorganic and organic composite conductive layer, an adhesive layer, and a conductive substrate layer. The adhesive layer contains a plurality of conductive particles in the adhesive and sequentially The inorganic and organic composite conductive layer has a through-hole array, so that some conductive particles enter the through-hole array with the adhesive. The conductive tape according to item 1 of the scope of patent application, wherein the composite conductive layer of the inorganic substance and the organic substance is silver paste, copper paste, aluminum silver paste, copper paste, indium tin oxide paste, tin antimony paste, and graphite paste. The graphite paste, graphene glue or graphene paste is formed on the surface of the release protective layer by gravure printing, and the thickness is 2-6 microns. The conductive tape according to item 1 or 2 of the patent application scope, wherein the adhesive layer is a polyacrylate pressure-sensitive adhesive layer with a thickness of 20-60 microns, and the conductive particles are conductive particles or / and conductive fibers. The conductive tape according to item 3 of the scope of patent application, wherein the conductive particles are selected from the group consisting of pure nickel powder, nickel-coated graphite powder, nickel-coated mica powder, silver powder, silver-plated mica, silver-plated hollow microspheres, and graphite powder. Body, graphene, or conductive carbon black; the conductive fiber is selected from the group consisting of nanometer silver wire, graphite fiber, graphene fiber, carbon fiber, silver-plated glass fiber, nickel-clad carbon fiber, or silver-plated carbon fiber. The conductive tape according to item 4 of the scope of patent application, wherein the conductive substrate layer is any one of pure metal foil, metal particles, metal microwires, metal nanowires, graphene, or a porous fiber material with a metal plating layer. Or a combination of 10-200 microns. The conductive tape according to item 4 of the scope of the patent application, wherein the through-hole array is a circular through-hole array, an oval through-hole array, a diamond-shaped through-hole array, a square through-hole array or a star-shaped through-hole array. The conductive tape according to item 4 of the scope of patent application, wherein the release protective layer is a PET film coated with a release agent on the surface or a paper coated with a release agent on the surface, and the thickness is 30-150 microns. A method for preparing a conductive tape as described in item 1 of the scope of the patent application, which comprises the following steps: Step 1: coating a composite conductive coating of a mixture of inorganic and organic substances on the surface of a release protective layer, and forming The inorganic and organic composite conductive layer of the through-hole array is cured by baking and expelling the solvent in the conductive coating, so that the inorganic and organic composite conductive layer is cured on the surface of the release protective layer; Step 2: Coating on the surface of the temporary release protective layer The paste containing a plurality of conductive particles is mixed, and the solvent in the paste is expelled by baking, so that the paste is cured on the surface of the temporary release protective layer to form an adhesive layer, and then the adhesive layer is relatively temporarily released from the protective layer. The other surface is bonded with a conductive substrate layer; and step three: unload the temporary release protective layer in the product of step two, and then make the release layer with a release layer on the other surface of the temporary conductive substrate layer and step one with a release The inorganic and organic composite conductive layers of the protective layer are bonded together. The method for preparing a conductive tape according to item 8 of the scope of the patent application, wherein the composite conductive layer of the inorganic substance and the organic substance is made by gravure printing. The method for preparing a conductive tape according to item 8 or 9 of the scope of the patent application, wherein the release protective layer is coated with a release agent in advance on the contact surface of the inorganic and organic composite conductive layer, and the release protective layer is temporarily opposed to the adhesive layer. The contact surface is previously coated with a release agent.