Conductive adhesive tape as well as preparation method and application thereof

Abstract

The invention provides a conductive adhesive tape and a preparation method and application thereof. The conductive adhesive tape comprises a polytetrafluoroethylene layer, a glass fabric layer, a first conductive adhesive layer, a polyethylene terephthalate film layer and a second conductive adhesive layer which are sequentially stacked. The conductive adhesive tape provided by the invention has excellent conductivity, adhesion, flame retardance and explosion-proof performance.

Description

Technical Field

[0001] The invention belongs to the technical field of conductive tapes, and in particular relates to a conductive tape and a preparation method and application thereof. Background Art

[0002] Conductive tape usually includes a conductive substrate of metal foil or conductive cloth, and an adhesive coated on the conductive substrate. It has bonding and shielding functions and is widely used in electronic products. It is mainly used to provide EMI / EMC electromagnetic compatibility solutions, connect different substrates and lines, and shield electromagnetic interference.

[0003] CN220485594U discloses a copper foil conductive tape, which includes a tape body, a wear-resistant layer, an antistatic layer, a copper foil layer and a release protective material arranged from top to bottom: an anti-oxidation coating is fixedly bonded between the wear-resistant layer and the antistatic layer, an adhesive layer is fixedly bonded between the antistatic layer and the copper foil layer, a conductive pressure-sensitive adhesive is fixedly bonded between the copper foil layer and the release protective material, the conductive pressure-sensitive adhesive is a sheet-shaped conductive powder, the diameter of the sheet-shaped conductive powder is selected to be 1μm to 100μm, and the thickness is selected to be a thin sheet powder of 0.1μm to 2μm, and the copper foil layer is a single-sided roughened copper foil. This technical solution designs the copper foil layer on the contact surface of the conductive pressure-sensitive adhesive to be a single-sided roughened copper foil, and with the same thickness, it can have a larger conductive contact area, increase the conductive contact points, and make the conductive interface contact larger, and the interface resistance is also reduced, so that the resistance of the copper foil conductive tape is reduced.

[0004] CN103484031A discloses a conductive tape, which comprises: a substrate and a colloid, wherein the substrate is a rectangular strip made of a conductive material, with a thickness of 0.02 to 1 mm and a conductive impedance of less than 0.4 Ω / cm 2 The heat resistance range is -20 to 110°C. The colloid is evenly coated on the lower surface of the substrate. The material is acrylic glue, the thickness is less than 0.04mm, and the adhesion is 1.1 to 1.3kg / cm 2 The conductive material includes aluminum foil, copper foil, conductive cloth, conductive silicon and conductive foam. The conductive tape provided by the technical solution has a simple structure, excellent electrical conductivity, and can effectively eliminate electromagnetic interference and isolate the harm of electromagnetic waves to the human body.

[0005] In the prior art, the conductive substrate of the conductive tape is metal foil or conductive cloth. However, although the metal foil or conductive cloth alone is used in combination with an adhesive and has bonding and shielding functions, the metal foil has low strength, poor explosion-proof performance, and a high price. Although the price of the conductive cloth is lower than that of the metal foil, its flame retardant effect is poor and it is easy to burn, resulting in poor applicability of the conductive tape to different environments.

[0006] Therefore, it is necessary to develop a conductive tape with good adhesion, good conductivity, flame retardancy and explosion-proof. Summary of the invention

[0007] In view of the shortcomings of the prior art, the present invention aims to provide a conductive tape and a preparation method and application thereof. The conductive tape has excellent conductivity, adhesion, flame retardancy and explosion-proof properties, and good interlayer bonding effect.

[0008] In order to achieve the purpose of the invention, the present invention adopts the following technical solutions:

[0009] In a first aspect, the present invention provides a conductive tape, comprising a polytetrafluoroethylene layer, a glass fiber cloth layer, a first conductive adhesive layer, a polyethylene terephthalate film layer, and a second conductive adhesive layer stacked in sequence.

[0010] In the present invention, the polytetrafluoroethylene layer and the glass fiber cloth layer have the characteristics of flame retardancy and high mechanical strength, and can provide explosion-proof performance and flame retardant performance; the first conductive adhesive layer can provide conductivity and interlayer adhesion, and the polyethylene terephthalate film layer is located between the first conductive adhesive layer and the second conductive adhesive layer to further enhance the explosion-proof performance. The materials of each layer structure of the conductive tape of the present invention are not explosive. In practical application as a wrapping material, even if the internal wrapped object explodes, the conductive tape will not produce a secondary explosion, and has good safety. The multilayer structure of the polytetrafluoroethylene layer, the glass fiber cloth layer, the first conductive adhesive layer, the polyethylene terephthalate film layer and the second conductive adhesive layer is compounded to give the conductive tape excellent conductivity, adhesion, flame retardant and explosion-proof performance, and the interlayer bonding effect is good, and it can be applied to a variety of environments.

[0011] Preferably, the polytetrafluoroethylene layer comprises a polytetrafluoroethylene film.

[0012] Preferably, the glass fiber cloth layer comprises glass fiber cloth.

[0013] Preferably, the raw material for preparing the first conductive adhesive layer includes a first conductive adhesive.

[0014] Preferably, the first conductive adhesive includes the following in parts by weight: 10 to 20 parts (11 parts, 12 parts, 13 parts, 14 parts, 15 parts, 16 parts, 17 parts, 18 parts or 19 parts, etc.) of epoxy resin, 30 to 70 parts (for example, 35 parts, 40 parts, 45 parts, 50 parts, 55 parts, 60 parts or 65 parts, etc.) of conductive filler and 10 to 20 parts (11 parts, 12 parts, 13 parts, 14 parts, 15 parts, 16 parts, 17 parts, 18 parts or 19 parts, etc.) of castor oil glycidyl ether.

[0015] Preferably, the mass percentage of the conductive filler in the first conductive adhesive is 60% to 65%, for example, 60.5%, 61%, 61.5%, 62%, 62.5%, 63%, 63.5%, 64% or 64.5%.

[0016] In the present invention, the weight proportion of the epoxy resin in the first conductive adhesive is preferably 10 to 20 parts. If the weight proportion of the epoxy resin is too much, the colloid of the first conductive adhesive layer will be too hard and the bendability will be poor; if the weight proportion of the epoxy resin is too little, the interlayer adhesion of the conductive tape will be insufficient; the conductive filler in the first conductive adhesive is preferably 30 to 70 parts. If the conductive filler is too much, the adhesive surface of the first conductive adhesive layer will be uneven and the interlayer bonding effect will be poor; if the conductive filler is too little, the resistance will increase and the conductive effect will deteriorate.

[0017] Preferably, the conductive filler in the first conductive adhesive includes nickel powder and graphite powder.

[0018] Preferably, the average particle size of the nickel powder in the first conductive adhesive is 10-30 μm, for example, 12 μm, 14 μm, 16 μm, 18 μm, 20 μm, 22 μm, 24 μm, 26 μm or 28 μm.

[0019] Preferably, the average particle size of the graphite powder in the first conductive adhesive is 20-30 μm, for example, 21 μm, 22 μm, 23 μm, 24 μm, 25 μm, 26 μm, 27 μm, 28 μm or 29 μm.

[0020] Preferably, the weight proportion of nickel powder in the first conductive adhesive is 10 to 30 parts, for example, 12 parts, 14 parts, 16 parts, 18 parts, 20 parts, 22 parts, 24 parts, 26 parts or 28 parts, and the weight proportion of graphite powder is 20 to 50 parts, for example, 23 parts, 26 parts, 29 parts, 32 parts, 35 parts, 38 parts, 41 parts, 44 parts or 47 parts, etc.

[0021] Preferably, the polyethylene terephthalate film layer comprises a polyethylene terephthalate film with both surfaces thereof being corona-treated.

[0022] In the present invention, the polyethylene terephthalate film treated by corona treatment has a good bonding effect when compounded with the first conductive adhesive layer and the second conductive adhesive layer, thereby improving the adhesion between the layers and making the compounding between the layers of the conductive tape more stable.

[0023] Preferably, the raw material for preparing the second conductive adhesive layer includes a second conductive adhesive.

[0024] Preferably, the second conductive adhesive comprises the following components in parts by weight: 70-90 parts of acrylic glue, 2-5 parts of methyl methacrylate, 2-5 parts of fluorine-containing acrylate and 5-30 parts of conductive filler.

[0025] Preferably, the mass percentage of the conductive filler in the second conductive adhesive is 10% to 25%, for example, 12%, 14%, 16%, 18%, 20%, 22% or 24%.

[0026] The conductive filler in the second conductive adhesive of the present invention is preferably 5 to 30 parts. If the conductive filler is too much, the adhesive surface of the second conductive adhesive will be uneven, resulting in low bonding strength with the bonded substrate and poor bonding effect; if the conductive filler is too low, the resistance will increase and the conductive effect will deteriorate.

[0027] Preferably, the average particle size of the conductive filler in the second conductive adhesive is 10-30 μm, for example, 12 μm, 14 μm, 16 μm, 18 μm, 20 μm, 22 μm, 24 μm, 26 μm or 28 μm.

[0028] Preferably, the conductive filler in the second conductive adhesive includes nickel powder.

[0029] Preferably, the thickness of the polytetrafluoroethylene layer is 15 to 25 μm, for example, 16 μm, 17 μm, 18 μm, 19 μm, 20 μm, 21 μm, 22 μm, 23 μm or 24 μm.

[0030] Preferably, the thickness of the glass fiber cloth layer is 10-100 μm, for example, 20 μm, 30 μm, 40 μm, 50 μm, 60 μm, 70 μm, 80 μm or 90 μm.

[0031] Preferably, the thickness of the first conductive adhesive layer is 10-50 μm, for example, 15 μm, 20 μm, 25 μm, 30 μm, 35 μm, 40 μm or 45 μm.

[0032] Preferably, the polyethylene terephthalate film layer has a thickness of 5 to 50 μm, for example, 10 μm, 15 μm, 20 μm, 25 μm, 30 μm, 35 μm, 40 μm or 45 μm.

[0033] Preferably, the second conductive adhesive layer has a thickness of 10-50 μm, for example, 15 μm, 20 μm, 25 μm, 30 μm, 35 μm, 40 μm or 45 μm.

[0034] In a second aspect, the present invention provides a method for preparing the conductive tape as described in the first aspect, the method comprising the following steps: coating a first conductive adhesive on the surface of a glass fiber cloth layer, performing a primary aging to form a first conductive adhesive layer, and then compounding one side of the glass fiber cloth layer with a polytetrafluoroethylene layer, compounding one side of the first conductive adhesive layer with a polyethylene terephthalate film layer, coating a second conductive adhesive on the surface of one side of the polyethylene terephthalate film layer, and performing a secondary aging to obtain the conductive tape.

[0035] Preferably, the primary aging temperature is 40-80°C (for example, 45°C, 50°C, 55°C, 60°C, 65°C, 70°C or 75°C, etc.), and the time is 24-96h (for example, 30h, 40h, 50h, 60h, 70h, 80h or 90h, etc.).

[0036] Preferably, the secondary aging temperature is 40-80°C (for example, 45°C, 50°C, 55°C, 60°C, 65°C, 70°C or 75°C, etc.), and the time is 24-96h (for example, 30h, 40h, 50h, 60h, 70h, 80h or 90h, etc.).

[0037] In the present invention, the first conductive adhesive is cured and tightly bonded to the glass fiber cloth layer by primary aging; the second conductive adhesive is tightly bonded to the polyethylene terephthalate film layer by secondary aging, thereby ensuring that each layer of material is tightly bonded.

[0038] In a third aspect, the present invention provides a use of the conductive tape as described in the first aspect in an electronic product.

[0039] Compared with the prior art, the present invention has the following beneficial effects:

[0040] In the present invention, the conductive tape is compounded by a multilayer structure of a polytetrafluoroethylene layer, a glass fiber cloth layer, a first conductive adhesive layer, a polyethylene terephthalate film layer, and a second conductive adhesive layer, which gives the conductive tape excellent conductivity, interlayer bonding strength, peeling strength, flame retardancy, and explosion-proof properties, making it suitable for a variety of environments. The first conductive adhesive layer of the conductive tape has a resistance of ≤0.155Ω, a resistance of ≤0.209Ω, an interlayer bonding strength of ≥200gf / 25.4mm, and a peeling strength of ≥500gf / 25.4mm. Preferably, the first conductive adhesive layer of the conductive tape has a resistance of ≤0.05Ω, a resistance of ≤0.05Ω, an interlayer bonding strength of ≥1000gf / 25.4mm, and a peeling strength of ≥1000gf / 25.4mm. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 A schematic diagram of the structure of the conductive tape provided in Example 1;

[0042] Among them, a1 is a glass fiber cloth layer; a2 is a polytetrafluoroethylene layer; a3 is a first conductive adhesive layer; a4 is a polyethylene terephthalate film layer; and a5 is a second conductive adhesive layer. DETAILED DESCRIPTION

[0043] The technical solution of the present invention is further described below by specific implementation methods. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0044] The sources of some components in the following examples and comparative examples are as follows:

[0045] Epoxy resin: brand TT386, manufacturer is Tiantai Chemical Technology Co., Ltd.;

[0046] Acrylic glue: brand CF-58, manufacturer is Kraft Lego Material Molecular Co., Ltd.;

[0047] Fluorinated acrylate: The brand name is CFU3270B, and the manufacturer is Kraft Lego Materials Molecular Co., Ltd.

[0048] Example 1

[0049] This embodiment provides a conductive tape and a method for preparing the same. Figure 1 As shown, the conductive tape includes a polytetrafluoroethylene layer a2, a glass fiber cloth layer a1, a first conductive adhesive layer a3, a polyethylene terephthalate film layer a4 and a second conductive adhesive layer a5 which are stacked in sequence.

[0050] The polytetrafluoroethylene layer a2 comprises a polytetrafluoroethylene film with a thickness of 15 μm;

[0051] The glass fiber cloth layer a1 comprises glass fiber cloth and has a thickness of 10 μm;

[0052] The thickness of the first conductive adhesive layer a3 is 10 μm;

[0053] The polyethylene terephthalate film layer a4 comprises a polyethylene terephthalate film with both surfaces subjected to corona treatment and a thickness of 5 μm;

[0054] The thickness of the second conductive adhesive layer a5 is 10 μm.

[0055] The preparation method comprises the following steps:

[0056] A first conductive adhesive is coated on the surface of the glass fiber cloth layer by a coating machine, and the layer is aged at 60°C for 48 hours to form a first conductive adhesive layer. Acrylic glue (CF-58) is then coated on the other side of the glass fiber cloth layer to compound with the polytetrafluoroethylene layer. One side of the first conductive adhesive layer is compounded with the polyethylene terephthalate film layer. A second conductive adhesive is coated on the surface of one side of the polyethylene terephthalate film layer by a coating machine, and the layer is aged for a second time at 60°C for 48 hours to obtain the conductive tape.

[0057] The first conductive adhesive is prepared by mixing 10 parts by weight of epoxy resin (TT386), 10 parts by weight of nickel powder (average particle size of 10 μm), 20 parts by weight of graphite powder (average particle size of 25 μm) and 10 parts by weight of castor oil glycidyl ether to obtain the first conductive adhesive.

[0058] The second conductive adhesive is prepared by mixing 70 parts by weight of acrylic glue (CF-58), 2 parts by weight of methyl methacrylate, 2 parts by weight of fluorinated acrylate and 10 parts by weight of nickel powder (average particle size of 10 μm) to obtain the second conductive adhesive.

[0059] Example 2

[0060] The present embodiment provides a conductive tape and a preparation method thereof. The conductive tape includes a polytetrafluoroethylene layer, a glass fiber cloth layer, a first conductive adhesive layer, a polyethylene terephthalate film layer, and a second conductive adhesive layer stacked in sequence.

[0061] The polytetrafluoroethylene layer comprises a polytetrafluoroethylene film having a thickness of 20 μm;

[0062] The glass fiber cloth layer comprises glass fiber cloth with a thickness of 50 μm;

[0063] The thickness of the first conductive adhesive layer is 25 μm;

[0064] The polyethylene terephthalate film layer includes a polyethylene terephthalate film with both surfaces subjected to corona treatment and a thickness of 25 μm;

[0065] The thickness of the second conductive adhesive layer is 15 μm.

[0066] The preparation method comprises the following steps:

[0067] A first conductive adhesive is coated on the surface of the glass fiber cloth layer by a coating machine, and the layer is aged once at 40° C. for 96 hours to form a first conductive adhesive layer. Acrylic glue (CF-58) is then coated on the other side of the glass fiber cloth layer to be compounded with the polytetrafluoroethylene layer. One side of the first conductive adhesive layer is compounded with the polyethylene terephthalate film layer. A second conductive adhesive is coated on the surface of one side of the polyethylene terephthalate film layer by a coating machine, and the layer is aged twice at 40° C. for 96 hours to obtain the conductive tape.

[0068] The first conductive adhesive is prepared by mixing 15 parts by weight of epoxy resin (TT386), 30 parts by weight of nickel powder (average particle size of 30 μm), 25 parts by weight of graphite powder (average particle size of 20 μm) and 15 parts by weight of castor oil glycidyl ether to obtain the first conductive adhesive.

[0069] The second conductive adhesive is prepared by mixing 80 parts by weight of acrylic glue (CF-58), 3 parts by weight of methyl methacrylate, 3 parts by weight of fluorinated acrylate and 20 parts by weight of nickel powder (average particle size of 20 μm) to obtain the second conductive adhesive.

[0070] Example 3

[0071] The present embodiment provides a conductive tape and a preparation method thereof. The conductive tape includes a polytetrafluoroethylene layer, a glass fiber cloth layer, a first conductive adhesive layer, a polyethylene terephthalate film layer, and a second conductive adhesive layer stacked in sequence.

[0072] The polytetrafluoroethylene layer comprises a polytetrafluoroethylene film having a thickness of 25 μm;

[0073] The glass fiber cloth layer comprises glass fiber cloth with a thickness of 100 μm;

[0074] The thickness of the first conductive adhesive layer is 50 μm;

[0075] The polyethylene terephthalate film layer comprises a polyethylene terephthalate film with both surfaces subjected to corona treatment and a thickness of 50 μm;

[0076] The thickness of the second conductive adhesive layer is 50 μm.

[0077] The preparation method comprises the following steps:

[0078] A first conductive adhesive is coated on the surface of the glass fiber cloth layer by a coating machine, and the layer is cured at 80°C for 24 hours to form a first conductive adhesive layer. Acrylic glue (CF-58) is then coated on the other side of the glass fiber cloth layer to be composited with the polytetrafluoroethylene layer. Then, the glass fiber and one side of the first conductive adhesive layer are composited with the polyethylene terephthalate film layer. A second conductive adhesive is coated on the surface of one side of the polyethylene terephthalate film layer by a coating machine, and the layer is cured for a second time at 80°C for 24 hours to obtain the conductive tape.

[0079] The first conductive adhesive is prepared by mixing 20 parts by weight of epoxy resin (TT386), 25 parts by weight of nickel powder (average particle size of 20 μm), 40 parts by weight of graphite powder (average particle size of 30 μm) and 20 parts by weight of castor oil glycidyl ether to obtain the first conductive adhesive.

[0080] The second conductive adhesive is prepared by mixing 90 parts by weight of acrylic glue (CF-58), 5 parts by weight of methyl methacrylate, 5 parts by weight of fluorinated acrylate and 30 parts by weight of nickel powder (average particle size of 30 μm) to obtain the second conductive adhesive.

[0081] Example 4

[0082] This embodiment provides a conductive tape and a preparation method thereof, which differs from Embodiment 1 only in that nickel powder is not added in the preparation of the first conductive adhesive, the weight fraction of graphite powder (average particle size of 25 μm) is adjusted to 30 parts, and other conditions are the same as those in Embodiment 1.

[0083] Example 5

[0084] This embodiment provides a conductive tape and a preparation method thereof, which differs from Embodiment 1 only in that no graphite powder is added in the preparation of the first conductive adhesive, the weight fraction of nickel powder (average particle size of 10 μm) is adjusted to 30 parts, and other conditions are the same as those in Embodiment 1.

[0085] Example 6

[0086] This embodiment provides a conductive tape and a preparation method thereof, which differs from Embodiment 1 only in that, in the preparation of the first conductive adhesive, the weight fraction of nickel powder (average particle size of 10 μm) is adjusted to 5 parts, and the weight fraction of graphite powder (average particle size of 25 μm) is adjusted to 25 parts, and other conditions are the same as those in Embodiment 1.

[0087] Example 7

[0088] This embodiment provides a conductive tape and a preparation method thereof, which differs from Embodiment 1 only in that, in the preparation of the first conductive adhesive, the weight fraction of nickel powder (average particle size of 10 μm) is adjusted to 25 parts, and the weight fraction of graphite powder (average particle size of 25 μm) is adjusted to 50 parts, and other conditions are the same as those in Embodiment 1.

[0089] Example 8

[0090] This embodiment provides a conductive tape and a preparation method thereof, which differs from Embodiment 1 only in that, in the preparation of the first conductive adhesive, the weight fraction of nickel powder (average particle size of 10 μm) is adjusted to 8 parts, and the weight fraction of graphite powder (average particle size of 25 μm) is adjusted to 16 parts, and other conditions are the same as those in Embodiment 1.

[0091] Example 9

[0092] This embodiment provides a conductive tape and a preparation method thereof, which differs from Embodiment 1 only in that the weight fraction of nickel powder (average particle size of 10 μm) is adjusted to 3 parts in the preparation of the second conductive adhesive, and other conditions are the same as those in Embodiment 1.

[0093] Example 10

[0094] This embodiment provides a conductive tape and a preparation method thereof, which differs from Embodiment 1 only in that the weight fraction of nickel powder (average particle size of 10 μm) is adjusted to 35 parts in the preparation of the second conductive adhesive, and other conditions are the same as those in Embodiment 1.

[0095] Embodiment 11

[0096] This embodiment provides a conductive tape and a preparation method thereof, which is different from Embodiment 1 only in that the weight portion of methyl methacrylate is adjusted to 1 part in the preparation of the second conductive adhesive, and other conditions are the same as those in Embodiment 1.

[0097] Example 12

[0098] This embodiment provides a conductive tape and a preparation method thereof. The only difference between this embodiment and embodiment 1 is that the weight fraction of methyl methacrylate in the preparation of the second conductive adhesive is adjusted to 6 parts, and other conditions are the same as those in embodiment 1.

[0099] Comparative Example 1

[0100] This comparative example provides an adhesive tape and a preparation method thereof, which is different from Example 1 only in that the conductive adhesive tape includes a polytetrafluoroethylene layer, a glass fiber cloth layer, a first adhesive layer, a polyethylene terephthalate film layer and a second adhesive layer stacked in sequence.

[0101] The polytetrafluoroethylene layer comprises a polytetrafluoroethylene film having a thickness of 15 μm;

[0102] The glass fiber cloth layer comprises glass fiber cloth with a thickness of 10 μm;

[0103] The thickness of the first adhesive layer is 10 μm;

[0104] The polyethylene terephthalate film layer comprises a polyethylene terephthalate film with both surfaces subjected to corona treatment and a thickness of 5 μm;

[0105] The thickness of the second adhesive layer was 10 μm.

[0106] The preparation method comprises the following steps:

[0107] A first adhesive is coated on the surface of the glass fiber cloth layer by a coating machine, and the layer is aged at 60°C for 48 hours to form a first adhesive layer. Acrylic glue (CF-58) is then coated on the other side of the glass fiber cloth layer to be compounded with the polytetrafluoroethylene layer. One side of the first adhesive layer is compounded with the polyethylene terephthalate film layer. A second adhesive is coated on the surface of one side of the polyethylene terephthalate film layer by a coating machine, and the layer is aged for a second time at 60°C for 48 hours to obtain the adhesive tape.

[0108] The first adhesive is prepared by the following method: 10 parts by weight of epoxy resin (TT386) and 10 parts by weight of castor oil glycidyl ether are mixed to obtain the first adhesive.

[0109] The second adhesive is prepared by the following method: 70 parts by weight of acrylic glue (CF-58), 2 parts by weight of methyl methacrylate and 2 parts by weight of fluorine-containing acrylate are mixed to obtain the second adhesive.

[0110] The conductive tapes provided in the above-mentioned Examples 1 to 12 and the tape provided in Comparative Example 1 were subjected to the following tests.

[0111] (1) Resistance performance: The resistance of the first conductive adhesive layer in the conductive tapes provided in Examples 1 to 12 and the resistance of the first adhesive layer in the tape provided in Comparative Example 1 were respectively tested according to MIL-DTL-83528C, and recorded as the first resistance; the resistance of the second conductive adhesive layer in the conductive tapes provided in Examples 1 to 12 and the resistance of the second adhesive layer in the tape provided in Comparative Example 1 were respectively tested according to MIL-DTL-83528C, and recorded as the second resistance;

[0112] (2) Flame retardant grade: tested in accordance with GB / T 8410-2006.

[0113] (3) Peel force: tested in accordance with GB / T 2792-2014 method 1.

[0114] (4) Interlayer bonding strength: The interlayer bonding strength between the glass fiber cloth layer and the first conductive adhesive layer or the first adhesive layer is tested according to GB / T2791-1995.

[0115] The test results are shown in Table 1 below.

[0116] Table 1

[0117]

[0118]

[0119] It can be seen from the contents of Table 1 that the flame retardant grade of the conductive tape provided in Examples 1 to 12 is B, the peel force is ≥500gf / 25.4mm, and the interlayer bonding force is ≥200gf / 25.4mm; the resistance of the first conductive adhesive layer in the conductive tape provided in Examples 1 to 12 is ≤0.155Ω, and the resistance of the second conductive adhesive layer is ≤0.209Ω, both of which have excellent conductivity.

[0120] Compared with Example 1, if nickel powder is not added in the preparation of the first conductive adhesive (Example 4), the resistance of the first conductive adhesive in the prepared conductive tape increases and the conductive performance decreases; if graphite powder is not added in the preparation of the first conductive adhesive (Example 5), the resistance of the first conductive adhesive in the prepared conductive tape increases and the conductive performance decreases. It can be seen that the conductive performance of the first conductive adhesive layer in the conductive tape prepared by compounding nickel powder and graphite powder in the present invention is better.

[0121] Compared with Example 1, if the weight fraction of nickel powder in the preparation of the first conductive adhesive is too small (Example 6), the resistance of the first conductive adhesive in the prepared conductive tape increases and the conductive performance decreases. It can be seen that in the present invention, the conductive performance of the first conductive adhesive layer in the prepared conductive tape is better by controlling the weight fraction of nickel powder in the first conductive adhesive within a specific range.

[0122] Compared with Example 1, if the weight fraction of the conductive filler in the preparation of the first conductive adhesive is too large (Example 7), the interlayer bonding force is reduced; if the weight fraction of the conductive filler in the preparation of the first conductive adhesive is too small (Example 8), the resistance of the first conductive adhesive layer increases and the conductive performance decreases.

[0123] Compared with Example 1, if the weight percentage of nickel powder in the preparation of the second conductive adhesive is too small (Example 9), the resistance of the second conductive adhesive layer increases and the conductive performance decreases; if the weight percentage of nickel powder in the preparation of the second conductive adhesive is too large (Example 10), the peeling force decreases and the viscosity of the conductive tape decreases.

[0124] Compared with Example 1, if the weight percentage of methyl methacrylate in the preparation of the second conductive adhesive is too small (Example 11), the dispersion uniformity of the conductive filler in the second conductive adhesive decreases, resulting in an increase in the resistance of the second conductive adhesive layer and a decrease in the conductive performance; if the weight percentage of methyl methacrylate in the preparation of the second conductive adhesive is too large (Example 12), the polymerization of the second conductive adhesive is affected, resulting in a decrease in the peeling force of the conductive tape obtained.

[0125] Compared with Example 1, the first adhesive layer and the second adhesive layer of the adhesive tape provided in Comparative Example 1 have large resistance and are not conductive.

[0126] The applicant declares that the present invention illustrates the process method of the present invention through the above-mentioned embodiments, but the present invention is not limited to the above-mentioned process steps, that is, it does not mean that the present invention must rely on the above-mentioned process steps to be implemented. Those skilled in the art should understand that any improvement of the present invention, equivalent replacement of the raw materials selected by the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A conductive tape, characterized in that: The conductive tape comprises a polytetrafluoroethylene layer, a glass fiber cloth layer, a first conductive adhesive layer, a polyethylene terephthalate film layer and a second conductive adhesive layer which are stacked in sequence.

2. The conductive tape according to claim 1, characterized in that: The polytetrafluoroethylene layer includes a polytetrafluoroethylene film; Preferably, the glass fiber cloth layer comprises glass fiber cloth.

3. The conductive tape according to claim 1 or 2, characterized in that: The raw materials for preparing the first conductive adhesive layer include a first conductive adhesive; Preferably, the first conductive adhesive comprises the following in parts by weight: 10 to 20 parts of epoxy resin, 30 to 70 parts of conductive filler and 10 to 20 parts of castor oil glycidyl ether; Preferably, the conductive filler in the first conductive adhesive comprises nickel powder and graphite powder; Preferably, the average particle size of the nickel powder in the first conductive adhesive is 10 to 30 μm; Preferably, the average particle size of the graphite powder in the first conductive adhesive is 20 to 30 μm; Preferably, the weight proportion of nickel powder in the first conductive adhesive is 10 to 30 parts, and the weight proportion of graphite powder is 20 to 50 parts; Preferably, the polyethylene terephthalate film layer comprises a polyethylene terephthalate film with both surfaces thereof being corona-treated.

4. The conductive tape according to any one of claims 1 to 3, characterized in that: The raw material for preparing the second conductive adhesive layer includes a second conductive adhesive; Preferably, the second conductive adhesive comprises the following components in parts by weight: 70-90 parts of acrylic glue, 2-5 parts of methyl methacrylate, 2-5 parts of fluorine-containing acrylate and 5-30 parts of conductive filler.

5. The conductive tape according to claim 4, characterized in that: The average particle size of the conductive filler in the second conductive adhesive is 10 to 30 μm; Preferably, the conductive filler in the second conductive adhesive includes nickel powder.

6. The conductive tape according to any one of claims 1 to 5, characterized in that: The thickness of the polytetrafluoroethylene layer is 15 to 25 μm; Preferably, the thickness of the glass fiber cloth layer is 10-100 μm.

7. The conductive tape according to any one of claims 1 to 6, characterized in that: The thickness of the first conductive adhesive layer is 10 to 50 μm; Preferably, the polyethylene terephthalate film layer has a thickness of 5 to 50 μm; Preferably, the second conductive adhesive layer has a thickness of 10-50 μm.

8. A method for preparing a conductive tape according to any one of claims 1 to 7, characterized in that: The preparation method comprises the following steps: coating a first conductive adhesive on the surface of a glass fiber cloth layer, performing a primary aging to form a first conductive adhesive layer, then compounding one side of the glass fiber cloth layer with a polytetrafluoroethylene layer, compounding one side of the first conductive adhesive layer with a polyethylene terephthalate film layer, coating a second conductive adhesive on the surface of one side of the polyethylene terephthalate film layer, performing a secondary aging to obtain the conductive tape.

9. The preparation method according to claim 8, characterized in that: The primary aging temperature is 40-80°C and the time is 24-96h; Preferably, the secondary aging temperature is 40-80° C. and the time is 24-96 hours.

10. Use of the conductive tape according to any one of claims 1 to 7 in electronic products.

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