A high temperature and high humidity resistant copper foil single-sided adhesive and its preparation method

Abstract

The present invention relates to the technical field of single-sided adhesives, and discloses a high-temperature and high-humidity resistant copper foil single-sided adhesive and its preparation method. The two sides of the copper foil are respectively set as the S side and the M side, and the two sides are electroplated: the zinc content of the S side coating is 20-25 mg / m 2 , chromium content 2.0~3.0mg / m 2 , Nickel content: 20~30mg / m 2 , M surface coating chromium content: 1.0~3.0mg / m 2 , Nickel content: 10~30mg / m 2 ; The coating on both sides is uniform, resistant to moisture, heat and smoke; high molecular weight, high acid value adhesive is selected, and tackifying resin and epoxy curing agent are added to obtain acrylic glue with high viscosity, good heat resistance, good water resistance and good aging resistance; after replacing part of the high molecular weight, high acid adhesive with small molecule additives, the moisture and heat resistance, flexibility and processability of the colloid are further improved. After being compounded with copper foil, the edges will not warp or bulge in high temperature and high humidity environments.

Description

Technical Field

[0001] The invention relates to the technical field of single-sided adhesives and discloses a high-temperature and high-humidity resistant copper foil single-sided adhesive and a preparation method thereof. Background Art

[0002] 3C electronic products (such as mobile phone displays and electronic panels) often experience heat generation during use. Existing technology often uses copper foil as a heat sink. Glue is coated on the surface of the copper foil to form a single-sided copper foil adhesive tape, which is then used to bond to cushioning foam to provide support, heat dissipation, and electromagnetic shielding. However, due to the high polarity of the foam surface, the glue used to bond the foam must be highly acidic. However, highly acidic glue is corrosive to the copper foil. After the adhesive layer bonds the copper foil and foam, it warps and bulges in high temperature and high humidity environments.

[0003] Copper foil has good thermal conductivity, electrical conductivity and electromagnetic shielding properties, but its heat resistance is poor and it is not suitable for use in high temperature environments. At the same time, copper foil is easily corroded in high humidity environments. In the existing technology, metal electroplated copper foil is a common surface treatment method and is widely used in the electronics industry. The advantages and disadvantages of common electroplated copper foils on the market are very obvious: for example, high-chromium electroplated copper foil is resistant to high temperature and high humidity, but due to the uneven chromium layer, the lines are obvious and the coating surface is yellow; nickel-plated copper foil can also withstand high temperature and high humidity, but the coating is iron gray, which is quite different from conventional copper foil, affecting the electrical and thermal properties of the copper foil; the zinc layer can prevent oxidation, but has poor water resistance; at the same time, to ensure the environmental adaptability of the copper foil single-sided tape after die-cutting and the reliability of the electromagnetic shielding effectiveness, the copper foil needs to be resistant to salt spray. The essence of salt spray corrosion is electrochemical corrosion: in a salt spray environment, since the salt spray liquid is an electrolyte, it will increase the probability of micro-batteries forming in the metal and accelerate the electrochemical corrosion process. Summary of the Invention

[0004] The purpose of the present invention is to provide a high temperature and high humidity resistant copper foil single-sided adhesive tape and a preparation method thereof, to prepare a copper foil single-sided adhesive tape that is resistant to high temperature, high humidity, high acid, salt spray, has a uniform coating without streaks, has a Lab value close to that of the raw copper foil, has good adhesion when bonded to foam, and has no edge warping or bulging, so as to solve the problems raised in the above background technology.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0006] A method for preparing a high-temperature and high-humidity resistant copper foil single-sided adhesive comprises the following steps:

[0007] S1: The two sides of the copper foil are set as the S side and the M side respectively, and the two sides are plated to obtain the S side plating layer and the M side plating layer, which are used as the electroplated copper foil;

[0008] S2: Coating acrylic adhesive on the M-side coating of the electroplated copper foil, and curing in an oven at 80-100° C. for 5-10 minutes to obtain a single-sided adhesive for the copper foil.

[0009] More optimally, the S surface is the cathode roller surface, and the M surface is the non-cathode roller surface.

[0010] More optimally, the copper foil has a thickness of 15 to 35 μm, and the acrylic adhesive coating has a thickness of 5 to 20 μm.

[0011] More optimally, the components of the S-side coating and the M-side coating of the electroplated copper foil include one or more metal elements selected from zinc, chromium, and nickel.

[0012] More optimally, the raw materials of the S-side coating include the following components: zinc content 20-25 mg / m 2 , chromium content 2.0~3.0mg / m 2 , Nickel content: 20~30mg / m 2 The raw materials of the M surface coating include the following components: chromium content 1.0 ~ 3.0mg / m 2 , Nickel content: 10~30mg / m 2 .

[0013] Zinc elements in the coating can prevent high-temperature oxidation; chromium and nickel elements in the coating can resist high temperature, high humidity, and salt spray; if there is an excess of chromium, the coating will be uneven, with line marks and yellow color; if there is an excess of nickel, the surface of the copper foil will be iron gray, which is quite different from the color of conventional copper foil, affecting the electrical and thermal properties of the copper foil.

[0014] Table 1 verifies the effect of nickel content on Lab value. As can be seen from Table 1, as the nickel content increases, the Lab value tends to decrease, affecting the appearance, and the nickel content needs to be controlled.

[0015] Test items Standard copper 100% Nickel content 150% Nickel content 200% Nickel content 250% Nickel content 300% L value 83.09 80.91 79.30 78.15 77.26 a value 14.55 11.93 11.07 10.19 9.50 b-value 15.67 12.06 11.38 10.69 10.24

[0016] Table 1

[0017] More optimally, in S1, the specific preparation process is: the two sides of the copper foil are set as the S side and the M side respectively, and after pickling both sides of the copper foil, they are first passed through a nickel tank, and nickel layers are electroplated on the S side and the M side with different currents to obtain S-side nickel layers and M-side nickel layers; then they are passed through a chromium tank 1, and a chromium layer is electroplated on the M-side nickel layer to obtain an M-side coating; and they are passed through a chromium tank 2 containing nickel and zinc, and metal is electroplated on the S-side nickel layer to obtain an S-side coating.

[0018] More optimally, the nickel bath comprises the following raw materials: nickel concentration is 15-30 g / L; the chromium bath 1 comprises the following raw materials: chromium concentration is 0.5-2.0 g / L; the chromium bath 2 containing nickel and zinc comprises the following raw materials: hexavalent chromium concentration is 1.0-3.0 g / L, zinc concentration is 7-10 g / L, and nickel concentration is 1-3 g / L;

[0019] In the S-side electroplating process of the nickel bath, the current density is 0.5~2.5A / dm 2 , temperature is 40~60℃, and electroplating time is 0.5~2.0min;

[0020] In the M-side electroplating process of nickel bath, the current density is 0.5~2.0A / dm 2 , temperature is 40~60℃, and electroplating time is 0.5~2.0min;

[0021] In the electroplating process of chromium tank 1, the current density is 0.5~5.0A / dm 2 , temperature is 25~40℃, and plating time is 0.5~2.0min;

[0022] In the electroplating process of the chromium bath 2 containing nickel and zinc, the current density is 0.5 to 5.0 A / dm 2 , temperature is 40~60℃, and electroplating time is 0.5~2.0min.

[0023] More optimally, the acrylic adhesive includes the following raw materials, calculated by weight: 90 to 110 parts of adhesive, 4 to 7 parts of curing agent, and 10 to 20 parts of tackifying resin; wherein the weight average molecular weight of the adhesive is 800,000 to 1.5 million.

[0024] More optimally, the acrylic adhesive includes the following raw materials, calculated by weight: 70 to 80 parts of adhesive, 20 to 30 parts of additive, 4 to 7 parts of curing agent, and 10 to 20 parts of tackifying resin; the preparation method of the additive includes the following steps: adding oligoacrylate to ethyl acetate, stirring evenly, adding initiator and long-chain comonomer under nitrogen protection, reacting, and after the reaction is completed, adding initiator and styrene again for a second reaction, and obtaining the additive after the reaction is completed.

[0025] More optimally, the additive includes the following raw materials, calculated by weight: 90 to 110 parts of oligoacrylate, 80 to 100 parts of ethyl acetate, 1 to 2 parts of initiator, 12 to 18 parts of styrene, and 8 to 12 parts of long-chain comonomer; the mass ratio of the long-chain comonomer to styrene is 2:3; the long-chain comonomer includes one or more of dodecyl to octadecyl acrylate.

[0026] More optimally, the initiator is benzoyl peroxide; the oligoacrylate is Sartomer CN104.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] (1) The machine speed and current were adjusted to prepare an electroplated copper foil containing three metal elements: zinc, chromium, and nickel. The ratio of the three metal elements was optimized, and the resulting coating was resistant to acrylic acid corrosion, high temperature and high humidity, and neutral salt spray. The coating was uniform and had no streaks. After nickel plating, the copper foil was passed through a chromium, zinc, and nickel mixing tank. The coating content on the cathode roller surface of the copper foil was increased in the acidic plating solution with the help of the promoting effect of zinc and nickel, so that the electroplated copper foil was still resistant to high temperature and high humidity after being bonded to acrylic glue with a high acid value.

[0029] (2) Use high molecular weight, high acid adhesive to improve bonding strength; compound tackifying resin to improve viscosity, which is also beneficial for bonding with copper foil; use epoxy curing agent, which can promote the formation of more chemical bonds during the curing process, and finally obtain acrylic adhesive with strong viscosity and resistance to high temperature and high humidity.

[0030] (3) A low molecular weight additive is added to the acrylic glue. The additive uses low polyacrylate as the base monomer. After grafting two copolymer monomers, the processability and viscosity of the colloid are further increased, and the heat and moisture resistance are also improved.

[0031] (4) When preparing additives, long-chain comonomers and comonomers with benzene rings are selected for grafting. Grafting long-chain comonomers increases the molecular weight and polarity of the adhesive, thereby increasing the viscosity of the adhesive. At the same time, the introduced long chains can increase the toughness of the adhesive, and grafting comonomers with benzene rings can increase the high temperature resistance and aging resistance of the adhesive. The best effect can be achieved by controlling the mass ratio of the two comonomers to 2:3. Excessive long-chain comonomers will lead to poor plasticity of the adhesive, and excessive comonomers with benzene rings will increase the brittleness of the adhesive. In this scheme, long-chain comonomers are grafted first, and then comonomers with benzene rings are grafted, thereby avoiding the influence of steric hindrance brought by the introduction of benzene ring structure on grafting efficiency. Finally, the adhesive is blended with high molecular weight acrylic glue to obtain a glue with high peel strength, good heat resistance, good moisture resistance and good aging resistance. After being compounded with copper foil, the edges will not curl or bulge in high temperature and high humidity environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0033] Figure 1 This is the appearance picture of the conventional copper foil adhesive ring after microscopic magnification 100 times;

[0034] Figure 2This is a 100-fold magnified appearance picture of the electroplated copper foil adhesive ring of Example 2 after testing. DETAILED DESCRIPTION

[0035] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0036] The raw materials in the examples are shown in Table 2:

[0037] Table 2:

[0038]

[0039]

[0040] The following parts are by mass;

[0041] Example 1: S1: A 20 μm raw copper foil was immersed in a hydrochloric acid solution for 4 minutes, washed with deionized water, and dried. The electroplating machine speed was maintained at 20 m / min and the temperature was maintained at 50° C. The S side of the copper foil was nickel-plated in a nickel bath at a current of 60 A, and the M side was nickel-plated in a nickel bath at a current of 35 A; the M side was chromium-plated in chromium bath 1 at a current of 40 A, and the S side was chromium-plated in chromium bath 2 at a current of 60 A to obtain an electroplated copper foil;

[0042] S2: Take 100 parts of adhesive, 5 parts of curing agent, and 15 parts of tackifying resin, mix well, and obtain acrylic glue;

[0043] S3: Apply acrylic adhesive to the M side of the electroplated copper foil with a coating thickness of 15 μm, and cure in an oven at 90° C. for 10 min to obtain a single-sided adhesive for the copper foil.

[0044] Example 2: S1: A 20 μm raw copper foil was immersed in a hydrochloric acid solution for 4 minutes, washed with deionized water, and dried. The electroplating machine speed was maintained at 20 m / min and the temperature was maintained at 50° C. The S side of the copper foil was nickel-plated in a nickel bath at a current of 70 A, and the M side was nickel-plated in a nickel bath at a current of 50 A; the M side was chromium-plated in chromium bath 1 at a current of 60 A, and the S side was chromium-plated in chromium bath 2 at a current of 70 A to obtain an electroplated copper foil;

[0045] S2: Add 100 parts of oligoacrylate to 100 parts of ethyl acetate, stir evenly, heat to 100°C under nitrogen protection, stir and uniformly add 3 / 4 part of initiator dropwise, the addition time is 1 hour, keep warm for 1 hour after the addition is completed, maintain 100°C, simultaneously add 1 / 4 part of initiator and 10 parts of hexadecyl acrylate dropwise, add dropwise for 2 hours, keep warm for 3 hours, heat to 150°C under nitrogen protection, stir and uniformly add dropwise 3 / 4 part of initiator, add dropwise for 1 hour, keep warm for 1 hour, maintain 150°C, simultaneously add dropwise 1 / 4 part of initiator and 15 parts of styrene, add dropwise for 2 hours, keep warm for 3 hours, and obtain the additive;

[0046] S3: Take 75 parts of adhesive, 5 parts of curing agent, 15 parts of tackifying resin, and 25 parts of additive, mix and stir for 30 minutes to obtain acrylic glue;

[0047] S4: Apply acrylic glue to the non-cathode roller surface of the electroplated copper foil with a coating thickness of 15 μm, and cure in an oven at 90° C. for 10 minutes to obtain a single-sided adhesive for the copper foil.

[0048] Example 3: S1: A 20 μm raw copper foil was immersed in a hydrochloric acid solution for 4 minutes, washed with deionized water, and dried. The electroplating machine speed was maintained at 20 m / min and the temperature was maintained at 50° C. The S side of the copper foil was nickel-plated in a nickel bath at a current of 80 A, and the M side was nickel-plated in a nickel bath at a current of 70 A; the M side was chromium-plated in chromium bath 1 at a current of 80 A, and the S side was chromium-plated in chromium bath 2 at a current of 80 A to obtain an electroplated copper foil;

[0049] S2: Take 100 parts of adhesive, 5 parts of curing agent, and 15 parts of tackifying resin, mix well, and obtain acrylic glue;

[0050] S3: Apply acrylic adhesive to the M side of the electroplated copper foil with a coating thickness of 15 μm, and cure in an oven at 90° C. for 10 min to obtain a single-sided adhesive for the copper foil.

[0051] Comparative Example 1: S1: A 20 μm raw copper foil was immersed in a hydrochloric acid solution for 4 minutes, washed with deionized water, and dried. The electroplating machine speed was maintained at 30 m / min and the temperature was 50° C. The S side of the copper foil was nickel-plated in a nickel bath at a current of 45 A, and the M side was nickel-plated in a nickel bath at a current of 25 A; the M side was chromium-plated in chromium bath 1 at a current of 30 A, and the S side was chromium-plated in chromium bath 2 at a current of 40 A to obtain an electroplated copper foil;

[0052] S2: Take 100 parts of adhesive, 5 parts of curing agent, and 15 parts of tackifying resin, mix well, and obtain acrylic glue;

[0053] S3: Apply acrylic adhesive to the M side of the electroplated copper foil with a coating thickness of 15 μm, and cure in an oven at 90° C. for 10 min to obtain a single-sided adhesive for the copper foil.

[0054] Comparative Example 2: S1: A 20 μm raw copper foil was immersed in a hydrochloric acid solution for 4 minutes, washed with deionized water, and dried. The electroplating machine speed was maintained at 30 m / min and the temperature was maintained at 50° C. The S side of the copper foil was nickel-plated in a nickel bath at a current of 55 A, and the M side was nickel-plated in a nickel bath at a current of 30 A; the M side was chromium-plated in chromium bath 1 at a current of 35 A, and the S side was chromium-plated in chromium bath 2 at a current of 50 A to obtain an electroplated copper foil;

[0055] S2: Take 100 parts of adhesive, 5 parts of curing agent, and 15 parts of tackifying resin, mix well, and obtain acrylic glue;

[0056] S3: Apply acrylic adhesive to the M side of the electroplated copper foil with a coating thickness of 15 μm, and cure in an oven at 90° C. for 10 min to obtain a single-sided adhesive for the copper foil.

[0057] Comparative Example 3: S1: A 20 μm raw copper foil was immersed in a hydrochloric acid solution for 4 minutes, washed with deionized water, and dried. The electroplating machine speed was maintained at 30 m / min and the temperature was maintained at 50°C. The S side of the copper foil was nickel-plated in a nickel bath at a current of 60 A, and the M side was nickel-plated in a nickel bath at a current of 35 A. The M side was chromium-plated in chromium bath 1 at a current of 40 A, and the S side was chromium-plated in chromium bath 2 at a current of 60 A to obtain an electroplated copper foil.

[0058] S2: Take 100 parts of adhesive, 5 parts of curing agent, and 15 parts of tackifying resin, mix well, and obtain acrylic glue;

[0059] S3: Apply acrylic adhesive to the M side of the electroplated copper foil with a coating thickness of 15 μm, and cure in an oven at 90° C. for 10 min to obtain a single-sided adhesive for the copper foil.

[0060] Comparative Example 4: S1: A 20 μm raw copper foil was immersed in a hydrochloric acid solution for 4 minutes, then removed and rinsed with deionized water and dried. The electroplating machine speed was maintained at 15 m / min and the temperature was 50°C. The copper foil was passed through a nickel bath as normal but no current was applied. The M side was chrome-plated in chrome bath 1 at a current of 85 A, and the S side was chrome-plated in chrome bath 2 at a current of 85 A to obtain an electroplated copper foil.

[0061] S2: Take 100 parts of adhesive, 5 parts of curing agent, and 15 parts of tackifying resin, mix well, and obtain acrylic glue;

[0062] S3: Apply acrylic adhesive to the M side of the electroplated copper foil with a coating thickness of 15 μm, and cure in an oven at 90° C. for 10 min to obtain a single-sided adhesive for the copper foil.

[0063] Comparative Example 5: S1: A 20 μm raw copper foil was immersed in a hydrochloric acid solution for 4 minutes, then washed with deionized water and dried. The electroplating machine speed was maintained at 15 m / min and the temperature was maintained at 50°C. The S side of the copper foil was nickel-plated in a nickel bath at a current of 80 A, and the M side was nickel-plated in a nickel bath at a current of 70 A. The copper foil was then passed through chromium baths 1 and 2 for chromium plating without applying current, thereby obtaining an electroplated copper foil.

[0064] S2: Take 100 parts of adhesive, 5 parts of curing agent, and 15 parts of tackifying resin, mix well, and obtain acrylic glue;

[0065] S3: Apply acrylic adhesive to the M side of the electroplated copper foil with a coating thickness of 15 μm, and cure in an oven at 90° C. for 10 min to obtain a single-sided adhesive for the copper foil.

[0066] Comparative Example 6: S1: A 20 μm raw copper foil was immersed in a hydrochloric acid solution for 4 minutes, washed with deionized water, and dried. The electroplating machine speed was maintained at 10 m / min and the temperature was 50° C. The S side of the copper foil was nickel-plated in a nickel bath at a current of 80 A, and the M side was nickel-plated in a nickel bath at a current of 70 A; the M side was chromium-plated in chromium bath 1 at a current of 85 A, and the S side was chromium-plated in chromium bath 2 at a current of 85 A to obtain an electroplated copper foil;

[0067] S2: Take 100 parts of adhesive, 5 parts of curing agent, and 15 parts of tackifying resin, mix well, and obtain acrylic glue;

[0068] S3: Apply acrylic adhesive to the M side of the electroplated copper foil with a coating thickness of 15 μm, and cure in an oven at 90° C. for 10 min to obtain a single-sided adhesive for the copper foil.

[0069] Comparative Example 7: S1: Take 100 parts of adhesive, 5 parts of curing agent, and 15 parts of tackifying resin, stir evenly, and obtain acrylic glue;

[0070] S2: Apply acrylic adhesive to the M side of the conventional plated copper foil with a coating thickness of 15 μm, and cure in an oven at 90°C for 10 minutes to obtain a single-sided copper foil adhesive.

[0071] Experiment 1:

[0072] (1) ICP (Inductively Coupled Plasma Emission Spectrometer) - Elemental Testing: 1. Cut the electroplated copper foils prepared in the Examples and Comparative Examples into pieces of 50 mm*50 mm in size, dissolve them in a 20% diluted nitric acid solution, transfer the solution and filter it; dilute to 50 ml with deionized water, and perform instrument testing;

[0073] (2) The electroplated copper foils prepared in Examples 1-3 and Comparative Examples 1-6 and the conventionally plated copper foil in Comparative Example 7 were placed in a test chamber at a temperature of 65° C. and a relative humidity of 90% for 72 hours, and the changes were observed;

[0074] (3) Using a colorimeter to measure the Lab values ​​of the electroplated copper foils obtained in the examples and comparative examples;

[0075] (4) Neutral salt spray test: The electroplated copper foils prepared in the examples and comparative examples were cut into a size of 100 mm*50 mm, placed in a salt spray test chamber at a 45° angle containing 5% saline, taken out after 8 hours, rinsed with deionized water, dried, and observed;

[0076] (5) The acrylic adhesives prepared in the examples and comparative examples and the blended adhesive prepared in Example 2 were measured for 180° peel strength with reference to GB / T2790-1995 standard.

[0077] The obtained data are shown in Table 3;

[0078] Table 3:

[0079]

[0080] Table 3 shows that Examples 1-3 are preferred. The acrylic adhesive prepared in Example 2 exhibits the highest peel strength, demonstrating the importance of additives. The electroplated copper foil prepared in Comparative Example 4 exhibits a high chromium content, resulting in the finished copper foil failing the ring test. This is primarily due to an uneven chromium layer.

[0081] Conclusion: Figure 1-2 It can be seen that the conventional plated copper foil cannot resist the acid corrosion in the adhesive layer and has obvious discoloration. The electroplated copper foil of Example 2 has no obvious change before and after the ring test.

[0082] Experiment 2:

[0083] The electroplated copper foils prepared in Examples 1-3 and Comparative Example 2 were tested for Lab values ​​before and after 3 days of ring measurement. The obtained data are shown in Table 4.

[0084] Table 4:

[0085] Test items Example 1 Example 2 Example 3 Comparative Example 2 L value (65 / 90~0 days) 83.77 83.73 82.11 84.02 L value (65 / 90~1 day) 82.51 83.05 82.03 83.10 L value (65 / 90~2 days) 81.97 82.34 81.63 81.56 L value (65 / 90~3 days) 81.65 82.03 81.07 80.14 a value (65 / 90~0 days) 14.11 14.04 13.65 14.67 a value (65 / 90~1 day) 14.63 14.51 13.81 15.30 a value (65 / 90~2 days) 14.95 14.79 14.09 16.17 a value (65 / 90~3 days) 15.34 15.08 14.21 17.05 b value (65 / 90~0 days) 15.19 15.16 14.87 15.86 b value (65 / 90~1 day) 15.43 15.36 14.97 16.46 b value (65 / 90~2 days) 16.08 15.80 15.18 17.30 b value (65 / 90~3 days) 16.72 16.15 15.29 18.08 in conclusion qualified qualified qualified Unqualified

[0086] As shown in Table 4, the color difference values ​​of Examples 1-3 before and after the ring test for 3 days are very small, and all meet the standards of the product color difference values ​​and are qualified; Comparative Example 2 meets the range of Lab values ​​after preparation, but does not meet the requirements of Lab after the ring test for 3 days and is unqualified.

[0087] In summary, to achieve the requirements of L value 83±3; a value 14.5±2.5; b value 15.5±2.5, it is necessary to control the nickel content and adjust the chromium content; the method provided by the present invention can produce copper foil that is resistant to high temperature and moisture, resistant to chemical corrosion, has a standard surface color without any discoloration, and has a bonding adhesive layer; the copper foil single-sided adhesive prepared by coating the prepared acrylic adhesive on the copper foil has high viscosity and good performance, which meets market demand.

[0088] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus.

[0089] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art will be able to modify the technical solutions described in the aforementioned embodiments or substitute equivalents for some of the technical features. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A method for preparing a high temperature and high humidity resistant copper foil single-sided adhesive, characterized in that: The following steps are involved: S1: The two sides of the copper foil are set as the S side and the M side respectively, and the two sides are plated to obtain the S side plating layer and the M side plating layer, which are used as the electroplated copper foil; S2: Coating acrylic adhesive on the M-side coating of the electroplated copper foil and curing in an oven at 80-100°C for 5-10 minutes to obtain a single-sided adhesive for the copper foil; The raw materials of the S-side coating include the following components: zinc content 20~25mg / m 2 、Chromium content 2.0~3.0mg / m 2 , Nickel content: 20~30mg / m 2 The raw materials of the M surface coating include the following components: chromium content 1.0~3.0mg / m 2 , Nickel content: 10~30mg / m 2 .

2. The method for preparing a high temperature and high humidity resistant copper foil single-sided adhesive according to claim 1, characterized in that: The copper foil has a thickness of 15 to 35 μm, and the acrylic adhesive has a coating thickness of 5 to 20 μm.

3. The method for preparing a high temperature and high humidity resistant copper foil single-sided adhesive according to claim 1, characterized in that: In S1, the specific preparation process is: the two sides of the copper foil are set as the S side and the M side respectively, and after pickling both sides of the copper foil, they are first passed through a nickel tank, and nickel layers are electroplated on the S side and the M side with different currents to obtain S-side nickel layers and M-side nickel layers; then they are passed through a chromium tank 1, and a chromium layer is electroplated on the M-side nickel layer to obtain an M-side coating; and they are passed through a chromium tank 2 containing nickel and zinc, and metal is electroplated on the S-side nickel layer to obtain an S-side coating.

4. The method for preparing a high temperature and high humidity resistant copper foil single-sided adhesive according to claim 3, characterized in that: The nickel bath includes the following raw materials: nickel concentration is 15-30 g / L; the chromium bath 1 includes the following raw materials: chromium concentration is 0.5-2.0 g / L; the chromium bath 2 containing nickel and zinc includes the following raw materials: hexavalent chromium concentration is 1.0-3.0 g / L, zinc concentration is 7-10 g / L, and nickel concentration is 1-3 g / L; In the S-side electroplating process of the nickel bath, the current density is 0.5~2.5A / dm 2 , temperature is 40~60℃, electroplating time is 0.5~2.0min; In the M-side electroplating process of nickel bath, the current density is 0.5~2.0A / dm 2 , temperature is 40~60℃, electroplating time is 0.5~2.0min; In the electroplating process of chromium tank 1, the current density is 0.5~5.0A / dm 2 , temperature is 40~60℃, electroplating time is 0.5~2.0min; In the electroplating process of the chromium bath 2 containing nickel and zinc, the current density is 0.5~5.0A / dm 2 , temperature is 40~60℃, and electroplating time is 0.5~2.0min.

5. The method for preparing a high temperature and high humidity resistant copper foil single-sided adhesive according to claim 1, characterized in that: The acrylic adhesive comprises the following raw materials, calculated by weight: 90 to 110 parts of adhesive, 4 to 7 parts of curing agent, and 10 to 20 parts of tackifying resin; wherein the weight average molecular weight of the adhesive is 800,000 to 1.5 million.

6. The method for preparing a high temperature and high humidity resistant copper foil single-sided adhesive according to claim 1, characterized in that: The acrylic adhesive comprises the following raw materials, calculated by weight: 70-80 parts of adhesive, 20-30 parts of additive, 4-7 parts of curing agent, and 10-20 parts of tackifying resin. The preparation method of the additive comprises the following steps: adding oligoacrylate to ethyl acetate, stirring evenly, adding initiator and long-chain comonomer under nitrogen protection, reacting, and after the reaction is completed, adding initiator and styrene again for a second reaction, and obtaining the additive after the reaction is completed.

7. The method for preparing a high temperature and high humidity resistant copper foil single-sided adhesive according to claim 6, characterized in that: The additive includes the following raw materials, calculated by weight: 90-110 parts of oligoacrylate, 80-100 parts of ethyl acetate, 1-2 parts of initiator, 12-18 parts of styrene, and 8-12 parts of long-chain comonomer; the mass ratio of the long-chain comonomer to styrene is 2:3; the long-chain comonomer includes one or more of dodecyl to octadecyl acrylate.

8. A high-temperature and high-humidity resistant copper foil single-sided adhesive obtained according to the preparation method of a high-temperature and high-humidity resistant copper foil single-sided adhesive according to any one of claims 1 to 7.

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