TW201811960A - High-conductivity adhesive tape capable of achieving an effect of stably increasing conductivity - Google Patents

Abstract

The present invention relates to a high-conductivity adhesive tape, which is formed by sequentially laminating a release type protective layer, an inorganic 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 conductive layer is provided with an array of through holes, so that part of the conductive particles enters the array of through holes by following the adhesive glue. As a result, it is able to solve the problem of instable conductivity in the prior art, hence, the disclosed achieves an effect of stably increasing conductivity.

Description

Highly conductive tape and preparation method thereof

The invention relates to a highly conductive adhesive tape and a preparation method thereof, in particular to an inorganic conductive layer that is in direct contact with a conductive adherend, and the inorganic conductive layer has a through-hole array, so that a part of the conductive particles of the adhesive layer follows Designer who glues glue into the through-hole array.

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 highly conductive adhesive tape of the present invention are a laminated protective layer, an inorganic conductive layer, an adhesive layer, and a conductive substrate layer, which are mixed in order. It contains a plurality of conductive particles, and the inorganic conductive layer has a through-hole array, so that some conductive particles enter the through-hole array with the adhesive.

In addition, the inorganic conductive layer is made of gold, silver, tin, copper, nickel, indium tin oxide or tin antimony, and is formed on the surface of the release protective layer by vacuum plating or chemical plating, 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 highly conductive tape of the present invention includes the following steps: Step 1: plating an inorganic conductive material on the surface of the release protective layer, and forming an inorganic conductive layer with a through-hole array on the surface of the release protective layer; Step 2: Apply a paste containing a plurality of conductive particles on the surface of the temporary release protective layer, and then expel the solvent in the paste by baking, so that the paste is cured on the surface of the temporary release protective layer to form an adhesive layer. Then, the conductive substrate layer is bonded on the other surface of the adhesive layer relative to the temporary release protective layer; and step 3: Unload the temporary release protective layer in the product of step 2 and then attach the adhesive layer to the temporary conductive substrate layer. The other surface is adhered to the inorganic conductive layer with the release protective layer made in step 1.

The inorganic conductive layer is made by vacuum plating or electroless plating. The contact surface of the release protective layer with respect to the inorganic conductive layer is previously coated with a release agent, and the contact surface of the temporary release protective layer with respect to the adhesive layer is previously coated with a release agent.

As a result, since the present invention adds an inorganic conductive layer that is in direct contact with the conductive adherend compared to the conventional conductive tape, and the inorganic conductive layer has a through-hole array, some of the conductive particles in the adhesive layer enter with the adhesive. In the through-hole array, the conductive particles and the conductive adherend are brought into contact from the original plane, and the inorganic conductive layer is evolved into a body contact.

First, please refer to [Fig. 1] to [Fig. 3], the highly conductive tape of the present invention is sequentially laminated and includes: a release protective layer 10, which can be a PET film or a surface coated with a release agent. A release agent-coated paper material having a thickness of 30-150 microns; an inorganic conductive layer 20, wherein the inorganic conductive layer is gold, silver, tin, copper, nickel, indium tin oxide, or tin antimony on the release protective layer 10 The surface is formed by vacuum plating or electroless plating and has a through-hole array 21 with a thickness of 2-6 micrometers. The through-hole array 21 can be a circular through-hole array (as shown in [Figure 3]) and an 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, which contains a plurality of conductive particles 31 in the adhesive, and some of the conductive particles 31 follow Adhesive glue enters the through-hole array 21, and the adhesive glue layer 30 may be a polyacrylate pressure-sensitive adhesive layer with a thickness of 20-60 microns, and the conductive particles 31 may be selected from pure nickel powder and nickel-coated graphite powder. Body, nickel-coated mica powder, silver powder, silver-plated mica, silver-plated hollow microspheres, graphite powder, graphene, or conductive carbon black Conductive particles or / and conductive fibers selected from nano-silver wires, graphite fibers, graphene fibers, carbon fibers, silver-plated glass fibers, nickel-clad carbon fibers, or silver-plated carbon fibers; and a conductive substrate layer 40, which may be a pure metal foil Any one or combination of metal particles, metal microwires, metal nanowires, graphene, or porous fiber materials with metal coatings, with a thickness of 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, inorganic conductive materials, and release protective materials can be other applicable materials in addition to the materials mentioned.

Example 1 Step 1: Using indium tin oxide as a target for vacuum plating, and vacuum plating by magnetron sputtering, the surface is coated with a release silicone oil (release force 8-12g) and a thickness of 75 microns. On the surface of the PET film, the thickness of the coating layer is 4 micrometers, and according to the array pattern with a line diameter of 200 micrometers and a square through hole of 1 mm × 1 mm, an acid solution wet etching process is used to etch and etch the coating surface After completion, an inorganic conductive layer having 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, then attach the polyacrylate pressure-sensitive adhesive layer to the other surface of the copper foil substrate and attach the inorganic conductive layer with the release protective layer in Step 1. , That is, the highly conductive tape constituting this embodiment.

Use a multimeter to test the resistance values of Example 1 and the conventional high-conductivity tape (excluding inorganic conductive layers). The test results are as follows: Tested according to ASTM D3330 standard Example 1 and conventional conductive tape (excluding inorganic 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 highly conductive tape were effectively improved.

Example 2 Step 1: Using gold as the target for vacuum plating, vacuum plating by magnetron sputtering, a 75 micron-thick PET film with a release silicone oil (release force 8-12g) on the surface On the surface, the thickness of the plating layer is 5 micrometers, and the surface of the plating layer is etched using an acid solution wet etching process in accordance with the array pattern with a circle hole diameter of 3 millimeters and a circle hole spacing of 500 micrometers. An inorganic PET conductive layer having 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 of Step 2, and then place the polyacrylate pressure-sensitive adhesive layer on the other surface of the nickel-plated conductive textile and step 1 to make an inorganic conductive layer sticker with a release protective layer. Together, this constitutes the highly conductive tape of this embodiment.

Use a multimeter to test the resistance values of Example 2 and the conventional conductive tape (excluding inorganic conductive layers). The test results are as follows: Tested according to ASTM D3330 standard Example 1 and conventional conductive tape (excluding inorganic conductive layer) to perform 180-degree peeling, the test results are as follows Test results: In Example 2, while ensuring sufficient adhesive strength, the conductive properties of the surface of the highly conductive tape were effectively improved.

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 conductive layer 20 is in direct contact with the conductive adherend, and the inorganic conductive layer 20 has a through-hole array 21, so that part of the conductive particles 31 of the adhesive layer 30 enters the through-hole array 21 with the adhesive, The conductive particles 31 and the conductive adherend are in the original planar contact form, and the inorganic conductive layer 20 evolves into a body contact form, which improves the total contact between the conductive particles 31 and the conductive adherend (direct contact + through the inorganic matter) The conductive layer 20 has an indirect contact) area; therefore, the present invention has the effects of stably improving the conductive performance and being quick to prepare.

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 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 conductive layer of the present invention. [Figure 3] A schematic diagram of a circular through-hole array of an inorganic conductive layer of the present invention.

Claims (10)

A high-conductivity adhesive tape is a laminated protective layer, an inorganic conductive layer, an adhesive layer, and a conductive substrate layer. The adhesive layer contains a plurality of conductive particles in the adhesive, and the The inorganic conductive layer has a through-hole array, so that some conductive particles enter the through-hole array with the adhesive. The highly conductive tape according to item 1 of the scope of patent application, wherein the conductive layer of the inorganic substance is gold, silver, tin, copper, nickel, indium tin oxide or tin antimony is formed on the release using vacuum plating or chemical plating. The surface of the protective layer is 2-6 microns thick. The high-conductivity adhesive tape according to item 1 or 2 of the scope of patent application, 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 highly conductive tape according to item 3 of the scope of patent application, wherein 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; 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 highly conductive tape according to item 4 of the scope of patent application, wherein the conductive substrate layer is made of pure metal foil, metal particles, metal microwires, metal nanowires, graphene, or a porous fiber material with a metal plating layer. Either or a combination of 10-200 microns. The high-conductivity 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 high-conductivity adhesive 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 highly conductive adhesive tape as described in item 1 of the scope of patent application, which comprises the following steps: Step 1: plating an inorganic conductive material on the surface of the release protective layer, and forming an array of through holes on the surface of the release protective layer. Inorganic conductive layer; step two: apply a paste containing a plurality of conductive particles on the surface of the temporary release protective layer, and then expel the solvent in the paste by baking, so that the paste is cured on the surface of the temporary release protective layer Forming an adhesive layer, and then laminating the conductive substrate layer on the other surface of the adhesive layer relative to the temporary release protective layer; and step three: unloading the temporary release protective layer in the product of step 2 and then relatively temporarily applying the adhesive layer The other surface of the conductive substrate layer is adhered to the inorganic conductive layer with the release protective layer made in step 1. The method for preparing a highly conductive tape according to item 8 of the scope of application for a patent, wherein the inorganic conductive layer is made by vacuum plating or chemical plating. The method for preparing a highly conductive tape according to item 8 or 9 of the scope of the patent application, wherein the contact surface of the release protective layer with respect to the inorganic conductive layer is previously coated with a release agent, and the contact of the temporary release protective layer with the adhesive layer is temporarily contacted. The surface is coated with a release agent in advance.