A method for preparing electronic copper foil, electronic copper foil and electronic product

Abstract

The present invention relates to the technical field of electronic copper foils, and particularly to a preparation method of an electronic copper foil, an electronic copper foil, and an electronic product. The preparation method of the electronic copper foil includes: roughening the surface of the original foil with a roughening solution to form a roughened surface, obtaining a roughened copper foil; the roughening solution includes the following components: 15 g / L to 40 g / L of copper, 30 g / L to 60 g / L of sulfuric acid, 1 g / L to 5 g / L of phosphoric acid, and water; the temperature of the roughening solution is 15 °C to 25 °C; the current density of the roughening treatment is 10 A / dm<supgt;2< / supgt> to 50 A / dm<supgt;2< / supgt>, the time is 3 s to 10 s, and the transmission speed of the original foil is 0.5 m / min to 14 m / min; performing an anti-oxidation treatment on the surface of the roughened copper foil to obtain an anti-oxidized copper foil; performing a silane coating treatment on the roughened surface of the anti-oxidized copper foil. By this method, the surface area of the roughened surface of the electronic copper foil can be increased, and the bonding force between the roughened surface of the electronic copper foil and the substrate can be improved.

Description

Technical Field

[0001] The present application relates to the technical field of electronic copper foil, and in particular to a method for preparing electronic copper foil, a method for preparing electronic copper foil, and an electronic product. Background Art

[0002] With the rapid development of electronic information technology, electronic products are constantly moving towards miniaturization, light weight, high performance and high reliability. As one of the basic materials of the electronics industry, electronic copper foil is widely used in printed circuit boards (PCBs), lithium-ion batteries and other fields. Its performance directly affects the overall quality and performance of electronic products. Electronic copper foil includes two main types: HVLP electronic copper foil and RTF electronic copper foil.

[0003] HVLP electronic copper foil, also known as high-frequency ultra-low profile electronic copper foil, is characterized by extremely low surface profile and excellent electrical properties, and one side is roughened. This copper foil is designed for high-frequency and high-speed circuits and is often used in the manufacture of printed circuit boards, especially in electronic products that have extremely high requirements for signal integrity. Its surface roughness is very low and has good adhesion, and it can be firmly bonded to copper-clad laminate substrates (such as epoxy resin or polyimide).

[0004] RTF electronic copper foil, also known as reverse processed copper foil or reverse ultra-low profile copper foil, has both sides of the copper foil roughened to enhance the peeling strength of both sides of the copper foil, making it easier to bond with other substrates as an intermediate layer.

[0005] The bonding strength between electronic copper foil and substrates such as epoxy resin, PPO, PTFE, etc. is one of the important indicators to measure the performance of electronic copper foil. In the prior art, it is often difficult to simultaneously achieve an extremely low profile on the copper foil surface and effectively improve the bonding strength between the copper foil and the substrate. For example, in the prior art, in order to increase the bonding strength between the electronic copper foil and the substrate, the roughness of the electronic copper foil is often increased. When the roughness increases, the profile of the electronic copper foil surface increases, and it is difficult to obtain an extremely low profile electronic copper foil. Summary of the invention

[0006] According to a first aspect of the present application, a method for preparing an electronic copper foil is provided, comprising the following steps:

[0007] The surface of the original foil is roughened by a roughening solution to form a roughened surface, thereby obtaining a roughened copper foil; the roughening solution comprises the following components: 15 g / L to 40 g / L copper, 30 g / L to 60 g / L sulfuric acid, 1 g / L to 5 g / L phosphoric acid, and water; the temperature of the roughening solution is 15°C to 25°C; the current density of the roughening treatment is 10 A / dm 2 ~50A / dm 2; The roughening treatment time is 3s~10s; The transmission speed of the original foil during the roughening treatment is 0.5m / min~14m / min;

[0008] performing an anti-oxidation treatment on the surface of the roughened copper foil to obtain an anti-oxidation copper foil;

[0009] The roughened surface of the oxidation-resistant copper foil is subjected to a silane coating treatment.

[0010] Preferably, the pH value of the roughening solution is 0.5-3.

[0011] Preferably, the electronic copper foil is an HVLP electronic copper foil, and in the roughening treatment, the roughening solution is used to perform a roughening treatment on a single-side surface of the original foil to form a single-side roughened surface.

[0012] Preferably, the electronic copper foil is an RTF electronic copper foil, and in the roughening treatment, the roughening solution is used to perform roughening treatment on the double-side surfaces of the original foil to form double-side roughened surfaces.

[0013] Preferably, the surface of the roughened copper foil is treated with an anti-oxidation solution; the anti-oxidation solution comprises the following components: phytic acid 1g / L~5g / L, zinc 1g / L~10g / L, nickel 1g / L~5g / L, nitric acid 0.1g / L~5g / L and water.

[0014] Preferably, the roughened surface of the anti-oxidation copper foil is subjected to silane coating treatment using a silane coating solution; the silane coating solution comprises fluorinated triethoxysilane and water.

[0015] Preferably, the mass percentage of the fluorotriethoxysilane in the silane coating solution is 0.1% to 2%.

[0016] Preferably, the preparation of the original foil comprises the following steps: preparing the original foil under electrolytic conditions using a copper deposition solution; the copper deposition solution comprises the following components: 70 g / L~100 g / L copper, 70 g / L~100 g / L sulfuric acid, 1 g / L~5 g / L brightener and water; the brightener comprises polypropylene glycol, gelatin and hydroxymethyl cellulose, and the mass ratio of the polypropylene glycol, the gelatin and the hydroxymethyl cellulose is 1: (1.5~2.5): (0.2~0.8).

[0017] According to a second aspect of the present application, an electronic copper foil is provided, which is prepared by the preparation method of the first aspect of the present application.

[0018] According to a third aspect of the present application, an electronic product is provided, comprising the HVLP electronic copper foil of the second aspect of the present application.

[0019] It can be seen from the above technical solution that this application has the following positive effects:

[0020] In the preparation method of the electronic copper foil of the present application, the specific formula of the roughening solution and the roughening condition design can achieve fine regulation of the surface microstructure of the copper foil by controlling the concentration of copper ions, sulfuric acid and phosphoric acid during the roughening process of the electronic copper foil, and the coordinated cooperation of each component.

[0021] Among them, sulfuric acid with a concentration of 30g / L~60g / L can effectively etch the surface of copper foil and control the surface roughness. Phosphoric acid with a concentration of 1g / L~5g / L can play a good buffering and auxiliary etching role for the etching of sulfuric acid, making the surface roughness of the roughened surface of the copper foil more uniform and reducing the risk of over-etching or uneven etching. During the roughening process, copper with a concentration of 15g / L~40g / L helps to maintain the electrochemical balance of the solution and ensure the stability and sustainability of the roughening process. The roughened surface of the electronic copper foil treated with the roughening solution can obtain an ideal surface roughness, thereby significantly increasing the surface area of ​​the roughened surface, laying a solid foundation for the subsequent improvement of the bonding strength with the substrate.

[0022] The preparation method can obtain extremely low-profile electronic copper foil.

[0023] Furthermore, the electronic copper foil prepared by the preparation method of the present application has high tensile strength and large elongation, and can remain in a non-oxidized state under high-temperature baking at 250 degrees Celsius. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The above and other features and advantages of the present application will become more apparent by describing in detail example embodiments thereof with reference to the attached drawings.

[0025] Figure 1 It is a structural schematic diagram of an integrated electronic copper foil production device in an embodiment of the present application.

[0026] Figure 2 It is a structural schematic diagram of a roughening device in an integrated electronic copper foil production equipment in an embodiment of the present application.

[0027] Figure 3 It is a schematic diagram of the structure of an HVLP electronic copper foil in an embodiment of the present application.

[0028] Figure 4 This is a surface structure diagram of the HVLP electronic copper foil in Example 1 of the present application.

[0029] Figure 5 It is a structural schematic diagram of an RTF electronic copper foil in an embodiment of the present application.

[0030] Figure 6This is a surface structure diagram of the roughened surface of the RTF electronic copper foil in Example 6 of the present application.

[0031] The main components in the figure are described as follows:

[0032] 1. Integrated electronic copper foil production equipment; 2. Sedimentation tank; 3. Roughening tank; 31. First positive plate; 32. Second positive plate; 33. Third positive plate; 34. Fourth positive plate; 4. Anti-oxidation tank; 5. Washing tank; 6. Titanium cathode roller; 7. Transfer roller; 10. Original foil (copper foil); 20. HVLP electronic copper foil; 201. Roughened surface of HVLP electronic copper foil; 202. Non-roughened surface. 30. RTF electronic copper foil; 301. Roughened surface of RTF electronic copper foil. DETAILED DESCRIPTION

[0033] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in a variety of forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this application will be comprehensive and complete and fully convey the concepts of the example embodiments to those skilled in the art. The same reference numerals in the figures represent the same or similar structures, and thus their detailed description will be omitted.

[0034] An embodiment of the present application provides a method for preparing an electronic copper foil, comprising the following steps: roughening the surface of the original foil with a roughening solution to form a roughened surface, thereby obtaining a roughened copper foil. The roughening solution comprises the following components: 15 g / L to 40 g / L copper, 30 g / L to 60 g / L sulfuric acid, 1 g / L to 5 g / L phosphoric acid, and water. The temperature of the roughening solution is 15°C to 25°C; the current density of the roughening treatment is 10 A / dm 2 ~50A / dm 2 The roughening treatment time is 3s to 10s; the transmission speed of the original foil during the roughening treatment is 0.5m / min to 14m / min. Anti-oxidation treatment is performed on both sides of the roughened copper foil to obtain an anti-oxidation copper foil; and silane coating is performed on the roughened surface on one side of the anti-oxidation copper foil.

[0035] In some embodiments, when the surface of the electronic copper foil is roughened by the roughening solution of the present application, the roughness Rz of the roughened surface of the electronic copper foil can be made less than 2 μm, thereby obtaining an extremely low-profile electronic copper foil.

[0036] At the same time, compared with the existing roughening solution, the roughening solution of the present application can increase the surface area of ​​the electronic copper foil by 200% to 500%, greatly improving the bonding force between the roughened surface of the electronic copper foil and the substrate.

[0037] It can be understood that in the roughening solution of the present application, the concentration of each component is expressed based on the volume of the roughening solution, and the mass of each component is based on the concentration of the volume of the roughening solution.

[0038] For example, the concentration of copper indicates the concentration of the mass of copper based on the volume of the roughening solution. Optionally, the concentration of copper can be, but is not limited to, 15 g / L, 18 g / L, 20 g / L, 22 g / L, 25 g / L, 28 g / L, 30 g / L, 32 g / L, 35 g / L, 38 g / L, 40 g / L. It is understood that the concentration of copper can also be other suitable selections within the range of 15 g / L-40 g / L.

[0039] For example, the concentration of sulfuric acid indicates the mass of sulfuric acid based on the volume of the roughening solution. Optionally, the concentration of sulfuric acid can be, but is not limited to, 30 g / L, 32 g / L, 35 g / L, 38 g / L, 40 g / L, 42 g / L, 45 g / L, 48 g / L, 50 g / L, 52 g / L, 55 g / L, 58 g / L, 60 g / L. It is understood that the concentration of sulfuric acid can also be other suitable selections within the range of 30 g / L to 60 g / L.

[0040] For example, the concentration of phosphoric acid indicates the concentration of the mass of phosphoric acid based on the volume of the roughening solution. Optionally, the concentration of phosphoric acid can be, but is not limited to, 1 g / L, 1.2 g / L, 1.5 g / L, 1.8 g / L, 2 g / L, 2.2 g / L, 2.5 g / L, 2.8 g / L, 3 g / L, 3.2 g / L, 3.5 g / L, 3.8 g / L, 4 g / L, 4.2 g / L, 4.5 g / L, 4.8 g / L, 5 g / L. It is understood that the concentration of phosphoric acid can also be other suitable selections within the range of 1 g / L to 5 g / L.

[0041] In some embodiments, the roughening solution is composed of the following components: 15 g / L to 40 g / L copper, 30 g / L to 60 g / L sulfuric acid, 1 g / L to 5 g / L phosphoric acid, and water. It is understood that in the electronic copper foil roughening solution of this embodiment, the concentration of copper, the concentration of sulfuric acid, and the concentration of phosphoric acid can be selected from the concentrations listed above, and will not be repeated here.

[0042] In some embodiments, the pH value of the roughening solution is 0.5 to 3. The pH value in this range can further improve the roughening effect, so that the roughened surface of the electronic copper foil can better balance the extremely low profile and the larger surface area. Optionally, the pH value of the roughening solution can be 0.5, 0.8, 1, 1.2, 1.5, 1.8, 2, 2.2, 2.5, 2.8, 3. It is understood that the pH value of the roughening solution can also be other suitable choices within the range of 0.5 to 3.

[0043] In some embodiments, when preparing electronic copper foil, the thickness of the original foil is 4 μm to 12 μm, and based on the original foil within this thickness range, an electronic copper foil with better performance can be obtained. Further preferably, the thickness of the original foil is 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, or 12 μm.

[0044] It is understandable that the raw foil can be a copper foil obtained by electrolytic deposition, or it can be a copper foil obtained by electrolytic deposition after some surface treatment. It is also understandable that when naming the copper foil, the "raw foil" and "copper foil" in this application do not strictly distinguish the copper foil, and the "raw foil" and "copper foil" are only formally distinguished between copper foils at different processing stages. For example, in the drawings of this application, the raw foil and the copper foil can be represented by the same reference numeral.

[0045] In some embodiments, the temperature of the roughening solution is 15°C to 25°C. During the roughening treatment, if the temperature of the roughening solution is too low, the roughening efficiency is low, and the activity of the roughening solution is low, it is difficult to obtain a good roughening effect; when the temperature of the roughening solution is too high, on the one hand, too much energy is consumed, and on the other hand, the roughening speed may be too fast, making it difficult to control the stable growth of the surface area of ​​the roughened surface of the electronic copper foil. Optionally, during the roughening treatment, the temperature of the roughening solution can be but is not limited to 15°C, 16°C, 17°C, 18°C, 19°C, 20°C, 21°C, 22°C, 23°C, 24°C, 25°C. It is understandable that the temperature of the roughening solution can also be other suitable choices within the range of 15°C to 25°C.

[0046] In some embodiments, the current density of the roughening process is 10A / dm 2 ~50A / dm 2 During the roughening treatment, if the current density of the roughening treatment is too small, it is difficult to obtain a high roughening efficiency, and if the current density of the roughening treatment is too large, it may be difficult to obtain a roughened surface with good consistency. Optionally, during the roughening treatment, the current density of the roughening treatment can be but is not limited to 10A / dm 2 、15A / dm 2 , 20A / dm 2 、25A / dm 2 、30A / dm 2 、35A / dm 2 、40A / dm 2 、45A / dm 2 、50A / dm 2 It is understood that the current density of the roughening treatment can also be 10A / dm 2 ~50A / dm 2 Make other appropriate choices within the scope.

[0047] In some embodiments, the time of the roughening treatment is 3s to 10s. During the roughening treatment, if the time of the roughening treatment is too short, it is difficult to obtain a good roughening effect. If the time of the roughening treatment is too long, on the one hand, it will produce higher energy consumption, and on the other hand, it may cause excessive damage to the electronic copper foil, affecting the performance of the electronic copper foil. Optionally, during the roughening treatment, the time of the roughening treatment can be but is not limited to 3s, 4s, 5s, 6s, 7s, 8s, 9s, 10s. It is understandable that the time of the roughening treatment can also be other suitable selections within the range of 3s to 10s.

[0048] In some embodiments, the transmission speed of the original foil during the roughening process is 0.5m / min~14m / min. During the roughening process, if the transmission speed of the original foil is too small, it may result in excessive roughening, which may cause excessive damage to the HVLP electronic copper foil and affect the performance of the electronic copper foil. If the transmission speed of the original foil is too large, it is difficult to obtain a sufficient roughening effect, which affects the performance of the roughened surface of the electronic copper foil. Optionally, during the roughening process, the transmission speed of the original foil can be but is not limited to 0.5m / min, 0.8m / min, 1m / min, 2m / min, 3m / min, 4m / min, 5m / min, 6m / min, 7m / min, 8m / min, 9m / min, 10m / min, 11m / min, 12m / min, 13m / min, 14m / min. It is understandable that during the roughening process, the transmission speed of the original foil can also be other suitable choices within the range of 0.5m / min~14m / min.

[0049] In some embodiments, an anti-oxidation solution is used to perform an anti-oxidation treatment on the surface of the roughened copper foil. The anti-oxidation solution includes the following components: phytic acid 1g / L~5g / L, zinc 1g / L~10g / L, nickel 1g / L~5g / L, nitric acid 0.1g / L~5g / L and water. By combining phytic acid, zinc, nickel and nitric acid, a solution with good anti-oxidation effect on electronic copper foil can be obtained. In particular, after the electronic copper foil is treated with the solution for anti-oxidation, the anti-oxidation performance of the electronic copper foil at high temperature can be effectively improved, so that the electronic copper foil maintains stable performance when hot-pressed with the substrate, and effectively promotes the improvement of the bonding force between the electronic copper foil and the substrate. At the same time, after the electronic copper foil is treated with the solution for anti-oxidation, the electronic copper foil can maintain good electrical and thermal conductivity, and after the electronic copper foil is applied to electronic products, the electronic products can maintain good performance.

[0050] Furthermore, the protective film formed on the surface of the electronic copper foil using the anti-oxidation solution of the present application can improve the corrosion resistance of the copper foil. The complex formed by phytic acid and metal ions can fill the tiny pores on the surface of the copper foil, making the surface of the electronic copper foil smoother and flatter, reducing the adhesion and penetration of the corrosive medium on the surface of the copper foil, thereby enhancing the resistance of the electronic copper foil to corrosive media such as acids, alkalis, and salts.

[0051] Specifically, phytic acid is an organic acid with strong chelating ability, and its molecular structure contains multiple phosphate groups. In the anti-oxidation solution, phytic acid can quickly react with copper ions on the surface of copper foil to form a tightly packed protective film with certain barrier properties. At the same time, the hydroxyl and phosphate groups of phytic acid can also complex with zinc ions and nickel ions, further strengthening the structural integrity and stability of the protective film, making it less likely to be destroyed in high temperature environments.

[0052] Zinc ions have a dual role in the solution. On the one hand, zinc is relatively chemically active and can undergo a certain degree of replacement reaction on the surface of the copper foil to form a zinc protective film. This zinc layer can act as a sacrificial anode and preferentially undergo oxidation reaction with oxygen in the surrounding environment, thereby delaying the oxidation process of the copper foil. On the other hand, after zinc ions are complexed with phytic acid, they can be evenly dispersed in the protective film, enhancing the overall protective performance of the protective film.

[0053] Nickel ions can form alloy phases or intermetallic compounds with phytic acid and copper atoms on the surface of copper foil. This special structure can significantly improve the hardness, wear resistance and high-temperature oxidation resistance of the protective film. Under high temperature conditions, the presence of nickel helps maintain the structural stability of the protective film and prevents it from softening, cracking or decomposing, thereby providing long-lasting and reliable protection for the copper foil.

[0054] Nitric acid plays a major role in adjusting the pH of the solution and promoting the dissolution and reaction of metal ions. By controlling the content of nitric acid, the reaction activity of the solution can be optimized to ensure that phytic acid, zinc ions and nickel ions can be fully dissolved and evenly distributed in the solvent, so that they can react efficiently when in contact with copper foil, forming a uniform, dense and high-performance anti-oxidation protective film.

[0055] The concentration of phytic acid in the anti-oxidation solution refers to the concentration of the mass of phytic acid based on the volume of the anti-oxidation solution. Optionally, the concentration of phytic acid can be 1g / L, 1.5g / L, 2g / L, 2.5g / L, 3g / L, 3.5g / L, 4g / L, 4.5g / L, 5g / L, etc. It is understood that the concentration of phytic acid can also be other suitable selections within the range of 1g / L to 5g / L.

[0056] The concentration of zinc in the anti-oxidation solution means the concentration of the mass of zinc based on the volume of the anti-oxidation solution. Optionally, the concentration of zinc can be 1g / L, 1.5g / L, 2g / L, 2.5g / L, 3g / L, 3.5g / L, 4g / L, 4.5g / L, 5g / L, 5.5g / L, 6g / L, 6.5g / L, 7g / L, 7.5g / L, 8g / L, 8.5g / L, 9g / L, 9.5g / L, 10g / L, etc. It is understood that the concentration of zinc can also be other suitable selections within the range of 1g / L to 10g / L.

[0057] The concentration of nickel in the anti-oxidation solution refers to the concentration of the mass of nickel based on the volume of the anti-oxidation solution. Optionally, the concentration of nickel can be 1g / L, 1.5g / L, 2g / L, 2.5g / L, 3g / L, 3.5g / L, 4g / L, 4.5g / L, 5g / L, etc. It is understood that the concentration of nickel can also be other suitable selections within the range of 1g / L to 5g / L.

[0058] The concentration of nitric acid in the anti-oxidation solution represents the concentration of the mass of nitric acid based on the volume of the anti-oxidation solution. Optionally, the concentration of nitric acid can be 0.1 g / L, 0.2 g / L, 0.3 g / L, 0.4 g / L, 0.5 g / L, 0.6 g / L, 0.7 g / L, 0.8 g / L, 0.9 g / L, 1 g / L, 1.5 g / L, 2 g / L, 2.5 g / L, 3 g / L, 3.5 g / L, 4 g / L, 4.5 g / L, 5 g / L, etc. It is understood that the concentration of nitric acid can also be other suitable selections within the range of 0.1 g / L to 5 g / L.

[0059] In some embodiments, in the anti-oxidation solution, the mass ratio of phytic acid, zinc, and nickel is 1:3:1.

[0060] In some embodiments, the concentration of chromium in the anti-oxidation solution is 0. In this embodiment, by designing the anti-oxidation solution, the anti-oxidation solution can still maintain a good anti-oxidation effect without using toxic metal chromium, which is conducive to promoting the green development of electronic copper foil production.

[0061] In some embodiments, the pH value of the anti-oxidation solution is 1 to 5. Within this pH range, phytic acid, zinc, nickel and nitric acid can cooperate better to further improve the anti-oxidation effect of the solution on electronic copper foil. It is understood that the pH value of the anti-oxidation solution can be adjusted by nitric acid. Optionally, the pH value of the anti-oxidation solution can be 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5, etc. It is understood that the pH value of the anti-oxidation solution can also be other suitable choices within the range of 1 to 5.

[0062] In some embodiments, the current density of the anti-oxidation treatment is 0.1 A / dm 2 ~10A / dm 2 If the current density is too small or too large, it is difficult to form a dense anti-oxidation film, which is not conducive to improving the anti-oxidation effect. Optionally, the current density of the anti-oxidation treatment can be 0.1A / dm 2 , 0.2A / dm 2 , 0.5A / dm 2 , 0.8A / dm 2 , 1A / dm 2 , 2A / dm 2 、3A / dm 2 , 4A / dm 2 , 5A / dm 2 、6A / dm 2 , 7A / dm 2 , 8A / dm 2 、9A / dm 2 、10A / dm 2 It is understood that the current density of the anti-oxidation treatment can also be 0.1A / dm 2 ~10A / dm 2 Make other appropriate choices within the scope.

[0063] In some embodiments, during the anti-oxidation treatment, the temperature of the anti-oxidation solution is 20°C~25°C. If the temperature of the anti-oxidation solution is too low or too high, it is difficult to form a dense anti-oxidation film, which is not conducive to improving the anti-oxidation effect. In this embodiment, anti-oxidation treatment at room temperature can provide a good anti-oxidation effect for the electronic copper foil. Optionally, the temperature of the anti-oxidation treatment can be 20°C, 21°C, 22°C, 23°C, 24°C, 25°C, etc. It is understandable that the temperature of the anti-oxidation solution can also be selected in other suitable ranges within the range of 20°C~25°C.

[0064] In some embodiments, the transmission speed of the roughened copper foil in the anti-oxidation treatment is 0.2m / min~15m / min. If the transmission speed of the roughened copper foil is too low, the production efficiency is low, and if the transmission speed of the roughened copper foil is too high, it is difficult to form a good anti-oxidation film. Optionally, the transmission speed of the roughened copper foil in the anti-oxidation treatment can be 0.2m / min, 0.5m / min, 0.8m / min, 1m / min, 2m / min, 5m / min, 8m / min, 10m / min, 12m / min, 15m / min, etc. It is understandable that the transmission speed of the roughened copper foil in the anti-oxidation treatment can also be other suitable selections within the range of 0.2m / min~15m / min.

[0065] In some embodiments, a silane coating solution is used to perform a silane coating treatment on the roughened surface of the anti-oxidation copper foil. The silane coating solution includes fluorotriethoxysilane and water. The silane coating solution is mainly composed of fluorotriethoxysilane and water. The silaneoxy group (-Si-OEt) in the fluorotriethoxysilane molecule can undergo a hydrolysis reaction to generate silanol (-Si-OH). These silanol groups can react chemically with oxides (such as copper oxide) on the surface of the copper foil and active hydroxyl groups in the microstructure formed by roughening to form a strong chemical bond, thereby tightly fixing the silane molecules on the surface of the copper foil. The fluorine group at the other end of the silane molecule has low surface energy and good chemical stability, and it can produce strong intermolecular forces such as van der Waals forces and hydrogen bonds with the substrate used subsequently. The synergistic effect of this chemical bonding and intermolecular force effectively improves the bonding force between the electronic copper foil and the substrate. At the same time, the presence of the fluorine group also gives the electronic copper foil a certain hydrophobicity and corrosion resistance, further improving the comprehensive performance of the electronic copper foil.

[0066] Optionally, the silane coating solution may be sprayed onto the roughened surface of the oxidation resistant copper foil.

[0067] Optionally, the mass percentage of fluorinated triethoxysilane in the silane coating solution is 0.1% to 2%. Optionally, the mass percentage of fluorinated triethoxysilane in the silane coating solution is 0.1%, 0.5%, 0.8%, 1%, 1.2%, 1.5%, 1.8%, 2%, etc. It is understandable that the mass percentage of fluorinated triethoxysilane in the silane coating solution can also be other suitable selections within the range of 0.1% to 2%.

[0068] In some embodiments, the preparation of the raw foil includes the following steps: preparing the raw foil under electrolytic conditions using a copper deposition solution. The copper deposition solution includes the following components: 70 g / L to 100 g / L copper, 70 g / L to 100 g / L sulfuric acid, 1 g / L to 5 g / L brightener, and water. The brightener includes polypropylene glycol, gelatin, and hydroxymethyl cellulose, and the mass ratio of polypropylene glycol, gelatin, and hydroxymethyl cellulose is 1: (1.5 to 2.5): (0.2 to 0.8). The raw foil with excellent surface quality can be obtained by the copper deposition solution. For example, the brightener including polypropylene glycol, gelatin, and hydroxymethyl cellulose can effectively improve the surface flatness and glossiness of the copper foil. During the electrolytic deposition process, these components can be adsorbed on the crystal surface of copper growth, inhibit the uneven growth of crystals, and reduce the formation of surface defects such as pitting and scratches, thereby making the surface of the copper foil smoother and flatter, which is beneficial for subsequent processing (such as roughening, anti-oxidation, etching, plating, etc.), and can improve processing accuracy and product yield.

[0069] The concentration of copper in the copper deposition solution indicates the concentration of the mass of copper based on the volume of the copper deposition solution. Optionally, the concentration of copper may be 70 g / L, 75 g / L, 80 g / L, 85 g / L, 90 g / L, 95 g / L, or 100 g / L. It is understood that the concentration of copper may also be other suitable selections within the range of 70 g / L to 100 g / L.

[0070] The concentration of sulfuric acid in the copper deposition solution refers to the concentration of the mass of sulfuric acid based on the volume of the copper deposition solution. Optionally, the concentration of sulfuric acid can be 70 g / L, 75 g / L, 80 g / L, 85 g / L, 90 g / L, 95 g / L, 100 g / L. It is understood that the concentration of sulfuric acid can also be other suitable selections within the range of 70 g / L to 100 g / L.

[0071] The concentration of the brightener in the copper deposition solution indicates the concentration of the mass of the brightener based on the volume of the copper deposition solution. Optionally, the concentration of the brightener may be 1 g / L, 1.5 g / L, 2 g / L, 2.5 g / L, 3 g / L, 3.5 g / L, 4 g / L, 4.5 g / L, 5 g / L, etc. It is understood that the concentration of the brightener may also be other suitable selections within the range of 1 g / L to 5 g / L.

[0072] Optionally, in the brightener, the mass ratio of polypropylene glycol, gelatin and hydroxymethyl cellulose can be 1:1.5:0.2, 1:1.5:0.5, 1:1.5:0.8, 1:2:0.2, 1:2:0.5, 1:2:0.8, 1:2.5:0.2, 1:2.5:0.5, 1:2.5:0.8. It is understandable that the mass ratio of polypropylene glycol, gelatin and hydroxymethyl cellulose can also be other suitable selections within the range of 1:(1.5-2.5):(0.2-0.8).

[0073] In some embodiments, when preparing the original foil, the temperature of the copper deposition liquid is 48°C to 52°C. If the temperature of the copper deposition liquid is too low, the deposition efficiency is low, and the activity of the copper deposition liquid is low, and it is difficult to obtain a good deposition effect; when the temperature of the copper deposition liquid is too high, on the one hand, too much energy is consumed, and on the other hand, the deposition speed may be too fast, making it difficult to control the stable deposition of the original foil. Optionally, when preparing the original foil, the temperature of the copper deposition liquid can be but is not limited to 48°C, 49°C, 50°C, 51°C, and 52°C. It is understandable that the temperature of the copper deposition liquid can also be other suitable selections within the range of 48°C to 52°C.

[0074] In some embodiments, the method for preparing the electronic copper foil further includes: before performing the anti-oxidation treatment on the surface of the roughened copper foil, washing the roughened copper foil with water. The water washing treatment can remove the residual solution on the surface of the roughened copper foil, thereby improving the effect of the subsequent anti-oxidation treatment.

[0075] In some embodiments, the present application also provides an integrated electronic copper foil production device. Figure 1 As shown, the integrated electronic copper foil production equipment 1 includes a deposition tank 2, a roughening tank 3 and an anti-oxidation tank 4. The deposition tank is used to prepare the original foil 10 by using the copper deposition liquid under the electrolysis of the titanium cathode roller 6. The roughening tank 3 is used to roughen the single-side surface of the original foil 10 to form a single-side roughened surface. The anti-oxidation tank 4 is used to perform anti-oxidation treatment on the double-side surfaces of the roughened copper foil.

[0076] It is understandable that the integrated electronic copper foil production equipment 1 further includes a transmission roller 7 , which is used to transmit the original foil 10 .

[0077] The integrated electronic copper foil production equipment of the present application can realize continuous production of the three key processes of foil production, roughening and anti-oxidation, thereby improving the production efficiency of the electronic copper foil.

[0078] Optionally, the integrated electronic copper foil production equipment 1 further includes a water washing tank 5. The water washing tank 5 is located between the roughening tank 3 and the anti-oxidation tank 4.

[0079] It can be understood that the deposition tank contains copper deposition solution, the roughening tank contains roughening solution, the anti-oxidation tank contains anti-oxidation solution, and the washing tank contains washing solution.

[0080] See also Figure 2 , a first positive electrode plate 31, a second positive electrode plate 32, a third positive electrode plate 33 and a fourth positive electrode plate 34 are provided in the roughening tank 3. On the transmission path of the original foil 10, the first positive electrode plate 31 and the second positive electrode plate 32 are located on the same side of the original foil 10, the third positive electrode plate 33 and the fourth positive electrode plate 34 are located on the same side of the original foil 10, and the first positive electrode plate 31 and the third positive electrode plate are located on opposite sides of the original foil 10. When the single-side surface of the original foil 10 is roughened, the first positive electrode plate 31 and the second positive electrode plate 32 can be opened, and the third positive electrode plate 33 and the fourth positive electrode plate 34 can be closed; or the first positive electrode plate 31 and the second positive electrode plate 32 can be closed, and the third positive electrode plate 33 and the fourth positive electrode plate 34 can be opened. When the double-side surface of the original foil 10 is roughened, the first positive electrode plate 31, the second positive electrode plate 32, the third positive electrode plate 33 and the fourth positive electrode plate 34 can be opened.

[0081] It is understandable that the electronic copper foil can be prepared using the integrated electronic copper foil production device 1 .

[0082] In some embodiments, the electronic copper foil is an HVLP electronic copper foil, and during the roughening treatment, a roughening solution is used to roughen a single-side surface of the original foil to form a single-side roughened surface.

[0083] See also Figure 3, which shows an HVLP electronic copper foil 20 in an embodiment of the present application. The HVLP electronic copper foil 20 has a roughened surface 201 and a non-roughened surface 202 opposite to the roughened surface 201. The roughness Rz of the roughened surface 201 of the HVLP electronic copper foil in an embodiment of the present application is less than 2 μm.

[0084] In some embodiments, the electronic copper foil is an RTF electronic copper foil. During the roughening treatment, a roughening solution is used to roughen the surfaces of both sides of the original foil to form roughened surfaces on both sides.

[0085] See also Figure 5 , which shows an RTF electronic copper foil 30 in an embodiment of the present application. The RTF electronic copper foil 30 has two oppositely disposed roughened surfaces 301. The roughness Rz of the two roughened surfaces 301 of the RTF electronic copper foil in an embodiment of the present application is less than 2 μm.

[0086] Example 1

[0087] The method for preparing the HVLP electronic copper foil in this embodiment includes the following steps:

[0088] S101: Prepare the original foil by using copper deposition solution under electrolytic conditions. The copper deposition solution includes the following components: 80 g / L copper, 80 g / L sulfuric acid, 2 g / L brightener and water. The brightener includes polypropylene glycol, gelatin and hydroxymethyl cellulose, and the mass ratio of polypropylene glycol, gelatin and hydroxymethyl cellulose is 1:2:0.5. The temperature of the copper deposition solution is 50°C. The thickness of the original foil is 5 μm.

[0089] S102: Roughening the single-side surface of the original foil with a roughening solution to form a single-side roughened surface, thereby obtaining a roughened copper foil. The roughening solution includes the following components: 25 g / L copper, 45 g / L sulfuric acid, 3 g / L phosphoric acid, and water. The temperature of the roughening solution is 20°C. The current density of the roughening treatment is 20 A / dm 2 The roughening treatment time was 5 s. The conveying speed of the original foil during the roughening treatment was 5 m / min.

[0090] S103: The roughened copper foil is washed with water.

[0091] S104: Anti-oxidation treatment is performed on the surface of the roughened copper foil after water washing to obtain an anti-oxidation copper foil. The anti-oxidation solution includes the following components: phytic acid 2g / L, zinc 5g / L, nickel 3g / L, nitric acid 2g / L and water. The current density of the anti-oxidation treatment is 5A / dm 2 The temperature of the anti-oxidation solution was 20° C. The conveying speed of the roughened copper foil during the anti-oxidation treatment was 5 m / min.

[0092] S105: performing silane coating treatment on the roughened surface of the anti-oxidation copper foil using a silane coating solution; the silane coating solution includes fluorinated triethoxysilane and water, and the mass percentage of fluorinated triethoxysilane in the silane coating solution is 1%.

[0093] See also Figure 4 , which shows the surface structure diagram of the HVLP electronic copper foil 20 in Example 1. (a) is the surface structure diagram of the non-roughened surface 202 of the HVLP electronic copper foil, and (b) is the surface structure diagram of the roughened surface 201 of the HVLP electronic copper foil. It can be seen from the figure that the roughened surface has good density and large specific surface area.

[0094] Examples 2 to 5, Comparative Examples 1 to 6

[0095] Compared with Example 1, the differences between Examples 2 to 5 and Comparative Examples 1 to 6 are shown in Table 1.

[0096] Comparative Example 7

[0097] The preparation method of the HVLP electronic copper foil in this comparative example comprises the following steps:

[0098] The roughening solution was used to roughen the single-side surface of the original foil with a thickness of 5 μm to form a single-side roughened surface, thereby obtaining a roughened copper foil. The roughening solution included the following components: 10 g / L copper, 80 g / L sulfuric acid, 1 g / L iron, 2 g / L molybdenum, and water. The temperature of the roughening solution was 20°C. The curing solution was used to cure the double-side surfaces of the roughened original foil, and the curing solution included the following components: 60 g / L copper, 60 g / L sulfuric acid, and the temperature of the curing solution was 40°C.

[0099] The roughness of the roughened surface of the HVLP electronic copper foil obtained in the examples and comparative examples (Rz, in micrometers), the peel strength between the roughened surface and the epoxy resin substrate after hot pressing at 200°C for 3 hours (in kg / cm), and the tensile strength of the HVLP electronic copper foil (in kg / mm 2 ), the elongation of the HVLP electronic copper foil and the oxidation condition of the HVLP electronic copper foil after baking at 200°C for 3h were tested, and the results are shown in Table 1.

[0100] Table 1

[0101]

[0102] It can be seen from Table 1 that the roughened surface of the HVLP electronic copper foil in the embodiment has a smaller Rz and has good bonding strength with the substrate. At the same time, the HVLP electronic copper foil has higher tensile strength and greater elongation, and has better anti-oxidation performance.

[0103] Example 6

[0104] The preparation method of RTF electronic copper foil in this embodiment includes the following steps:

[0105] S101: Prepare the original foil by using copper deposition solution under electrolytic conditions. The copper deposition solution includes the following components: 80 g / L copper, 80 g / L sulfuric acid, 2 g / L brightener and water. The brightener includes polypropylene glycol, gelatin and hydroxymethyl cellulose, and the mass ratio of polypropylene glycol, gelatin and hydroxymethyl cellulose is 1:2:0.5. The temperature of the copper deposition solution is 50°C. The thickness of the original foil is 5 μm.

[0106] S102: The surfaces of both sides of the original foil are roughened with a roughening solution to form roughened surfaces on both sides, thereby obtaining a roughened copper foil. The roughening solution includes the following components: 25 g / L copper, 45 g / L sulfuric acid, 3 g / L phosphoric acid, and water. The temperature of the roughening solution is 20°C. The current density of the roughening treatment is 20 A / dm 2 The roughening treatment time was 5 s. The conveying speed of the original foil during the roughening treatment was 5 m / min.

[0107] S103: The roughened copper foil is washed with water.

[0108] S104: Anti-oxidation treatment is performed on the surface of the roughened copper foil after water washing to obtain an anti-oxidation copper foil. The anti-oxidation solution includes the following components: phytic acid 2g / L, zinc 5g / L, nickel 3g / L, nitric acid 2g / L and water. The current density of the anti-oxidation treatment is 5A / dm 2 The temperature of the anti-oxidation solution was 20° C. The conveying speed of the roughened copper foil during the anti-oxidation treatment was 5 m / min.

[0109] S105: performing silane coating treatment on the roughened surface of the anti-oxidation copper foil using a silane coating solution; the silane coating solution includes fluorinated triethoxysilane and water, and the mass percentage of fluorinated triethoxysilane in the silane coating solution is 1%.

[0110] See also Figure 6 , which shows the surface structure diagram of the roughened surface 301 of the RTF electronic copper foil 30 in Example 6. As can be seen from the figure, the roughened surface has good density and large specific surface area.

[0111] Examples 7-10, Comparative Examples 8-13

[0112] Compared with Example 6, the differences between Examples 7 to 10 and Comparative Examples 8 to 13 are shown in Table 2.

[0113] Comparative Example 14

[0114] The preparation method of the RTF electronic copper foil in this comparative example comprises the following steps:

[0115] The roughening solution was used to roughen the double-sided surfaces of the original foil with a thickness of 5 μm to form a double-sided roughened surface, thereby obtaining a roughened copper foil. The roughening solution included the following components: 10 g / L copper, 80 g / L sulfuric acid, 1 g / L iron, 2 g / L molybdenum, and water. The temperature of the roughening solution was 20°C. The double-sided surfaces of the roughened original foil were cured by a curing solution, the curing solution included the following components: 60 g / L copper, 60 g / L sulfuric acid, and the temperature of the curing solution was 40°C.

[0116] The roughness of the roughened surface of the RTF electronic copper foil obtained in the examples and comparative examples (Rz, in micrometers), the peel strength between the roughened surface and the epoxy resin substrate after hot pressing at 200°C for 3 hours (in kg / cm), and the tensile strength of the RTF electronic copper foil (in kg / mm 2 ), the elongation of the RTF electronic copper foil and the oxidation condition of the RTF electronic copper foil after baking at 200°C for 3h were tested, and the results are shown in Table 1.

[0117] Table 2

[0118]

[0119] It can be seen from Table 2 that the roughened surface of the RTF electronic copper foil in the embodiment has a smaller Rz and has good bonding strength with the substrate. At the same time, the RTF electronic copper foil has higher tensile strength and greater elongation, and has better anti-oxidation performance.

[0120] It should be understood that the present application does not limit its application to the detailed structure and arrangement of the components proposed in the present application. The present application can have other embodiments and can be implemented and executed in a variety of ways. The aforementioned variations and modifications fall within the scope of the present application. It should be understood that the present application and the defined present application extend to all alternative combinations of two or more individual features mentioned or apparent in the text and / or the accompanying drawings. All these different combinations constitute multiple alternative aspects of the present application. The embodiments described in the present application illustrate the best mode known for implementing the present application and will enable those skilled in the art to utilize the present application.

Claims

1. A method for preparing an electronic copper foil, characterized in that: The steps include: The surface of the original foil is roughened by a roughening solution to form a roughened surface, thereby obtaining a roughened copper foil; the roughening solution is composed of the following components: 15 g / L to 40 g / L copper, 30 g / L to 60 g / L sulfuric acid, 1 g / L to 5 g / L phosphoric acid, and water; the temperature of the roughening solution is 15°C to 25°C; the current density of the roughening treatment is 10 A / dm 2 ~50A / dm 2 ; The roughening treatment time is 3s~10s; The transmission speed of the original foil during the roughening treatment is 0.5m / min~14m / min; performing an anti-oxidation treatment on the surface of the roughened copper foil to obtain an anti-oxidation copper foil; The roughened surface of the oxidation-resistant copper foil is subjected to a silane coating treatment.

2. The method for preparing electronic copper foil according to claim 1, characterized in that: The pH value of the roughening solution is 0.5-3.

3. The method for preparing electronic copper foil according to claim 1, characterized in that: The electronic copper foil is an HVLP electronic copper foil. In the roughening treatment, the roughening solution is used to perform a roughening treatment on a single-side surface of the original foil to form a single-side roughened surface.

4. The method for preparing electronic copper foil according to claim 1, characterized in that: The electronic copper foil is an RTF electronic copper foil. In the roughening treatment, the roughening solution is used to perform roughening treatment on the double-side surfaces of the original foil to form double-side roughened surfaces.

5. The method for preparing an electronic copper foil according to any one of claims 1 to 4, characterized in that: Using an anti-oxidation solution to perform an anti-oxidation treatment on the surface of the roughened copper foil; The anti-oxidation solution comprises the following components: phytic acid 1g / L-5g / L, zinc 1g / L-10g / L, nickel 1g / L-5g / L, nitric acid 0.1g / L-5g / L and water.

6. The method for preparing an electronic copper foil according to any one of claims 1 to 4, characterized in that: Using a silane coating solution to perform a silane coating treatment on the roughened surface of the anti-oxidation copper foil; The silane coating solution includes fluorotriethoxysilane and water.

7. The method for preparing electronic copper foil according to claim 6, characterized in that: The mass percentage of the fluorotriethoxysilane in the silane coating solution is 0.1% to 2%.

8. The method for preparing an electronic copper foil according to any one of claims 1 to 4, characterized in that: The preparation of the raw foil comprises the following steps: The raw foil is prepared by using a copper deposition solution under electrolytic conditions; The copper deposition solution includes the following components: 70 g / L~100 g / L copper, 70 g / L~100 g / L sulfuric acid, 1 g / L~5 g / L brightener and water; the brightener includes polypropylene glycol, gelatin and hydroxymethyl cellulose, and the mass ratio of the polypropylene glycol, the gelatin and the hydroxymethyl cellulose is 1: (1.5~2.5): (0.2~0.8).

9. An electronic copper foil, characterized in that: Prepared by the preparation method described in any one of claims 1 to 8.

10. An electronic product, characterized in that: The electronic copper foil according to claim 9 is included.

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