Production process for effectively improving water ripples of electrolytic copper foil

Abstract

The invention discloses a production process for effectively improving water ripples of an electrolytic copper foil, and relates to the technical field of ultrathin copper foil production, and the production process comprises the following specific steps: step 1, adding a copper wire, concentrated sulfuric acid and a lead sulfate solution into a copper dissolving tank, and fully and uniformly mixing the copper wire, the concentrated sulfuric acid and the lead sulfate solution; 2, preparing a copper sulfate electrolyte with the sulfuric acid concentration of 90-120 g / L, the copper concentration of 80-95 g / L, the chloride ion concentration of 10-20 mg / L and the lead ion concentration of 1-5 mg / L; and 3, maintaining the concentration of the electrolyte to be stabilized at 50-55 DEG C. According to the production process, on the premise that the production efficiency and the production stability are not affected, through simple and convenient operation, the uniformity of copper foil electro-deposition is improved, the water ripple defect of the copper foil is improved, direct waste of the copper foil caused by the water ripple defect is reduced, and the time cost and the production cost are reduced; the surface coating of the anode plate is protected, the service life of the anode plate is prolonged, and the production cost is reduced; and the quality stability of copper foil products is improved, the problems occurring in the use process of clients are reduced, and the customer complaint rate is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of ultra-thin copper foil production, in particular to a production process for effectively improving water ripples in electrolytic copper foil. Background Art

[0002] With the development of the electronics industry, the market demand and requirements for ultra-thin copper foil are gradually increasing, and ultra-thin electrolytic copper foil has more stringent requirements on technology, equipment and environment; the production process of electrolytic copper foil generally includes steps such as dissolving copper to make liquid, filtering, pumping into the cathode roller and anode plate of the foil machine for electrolysis, copper ions are deposited on the surface of the cathode roller under the action of the electric field, peeling and winding, anti-oxidation post-treatment, winding, slitting and packaging; copper foil will produce various defects in the process of electrodeposition, and its quality and appearance quality have a great influence on the manufacturing process of lithium battery negative electrode; among them, the water ripple defect problem of copper foil has many adverse effects on the production process of downstream customers, and is easy to cause wrinkling on the upper roll, broken tape during coating, shaking of foil, folding of the tab and other problems, affecting customer use; therefore, when the supplier ships, the copper foil with severe water ripples on the outer side of the finished foil will be peeled off and discarded to avoid customer complaints. At the same time, it also causes the problem of reduced copper foil output and increased production costs.

[0003] The main reason for the water ripples is the uneven electrodeposition of copper foil on the cathode roller. At present, the common measures to improve the water ripple defects of copper foil are: 1. Reduce the weight deviation of the copper foil over the entire width, that is, adjust the liquid flow rate in different areas when the raw foil machine is feeding the liquid so that the weight deviation of the copper foil over the entire width of the cathode roller is small. This measure requires manual adjustment of valves in different areas of the liquid flow rate. The operation is cumbersome and requires manual inspection and review, which increases the time cost, and the improvement effect is not obvious due to the fluctuation of the liquid flow rate on the raw foil machine; 2. The surface coating of the anode plate is damaged, causing the anode plate to fail, resulting in uneven electrodeposition of copper foil. After replacing the anode plate, the water ripples are improved to a certain extent, but as the use time of the anode plate increases, the water ripple defects become more and more serious, resulting in a significant shortening of the life of the anode plate, and the raw foil machine must be shut down to replace the anode plate. It takes 1-2 days from dismantling the old anode plate to installing the new anode plate, which greatly affects production capacity.

[0004] Adjusting the valve in the liquid area of ​​the raw foil machine is cumbersome, and after adjustment, sampling needs to be done for manual inspection and verification, which increases the time cost. In addition, reducing the weight deviation of the entire width of the copper foil has little effect on improving the water ripples. There is still a large amount of copper foil directly scrapped due to water ripple defects, which greatly increases the production cost of the copper foil.

[0005] Improving water ripples by replacing anode plates greatly shortens the service life of the anode plates, resulting in a certain waste of production costs; frequent shutdowns to replace anode plates will directly affect production efficiency and are not conducive to production stability. Summary of the invention

[0006] In view of the deficiencies of the prior art, the present invention provides a production process for effectively improving the water ripples of electrolytic copper foil, which solves the problems raised in the above-mentioned background art.

[0007] To achieve the above objectives, the present invention is realized through the following technical solutions: A production process for effectively improving the water ripples of electrolytic copper foil, including the following specific steps:

[0008] Step 1: Add copper wire, concentrated sulfuric acid, and lead sulfate solution to the copper dissolution tank and mix them thoroughly.

[0009] Step 2: Prepare a copper sulfate electrolyte with a sulfuric acid concentration of 90 - 120 g / L, a copper concentration of 80 - 95 g / l, a chloride ion concentration of 10 - 20 mg / L, and a lead ion concentration of 1 - 5 mg / L.

[0010] Step 3: Maintain the electrolyte concentration stable at a temperature of 50 - 55 °C.

[0011] Step 4: Add a combined additive of inhibitor PEG, brightener SPS, and leveling agent collagen.

[0012] Step 5: In a foil making machine with an iridium-plated titanium anode plate as the anode and a titanium roller as the cathode;

[0013] Step 6: Under the action of a DC power supply, electroplate a 6 μm ultra-thin copper foil on the cathode roller.

[0014] Step 7: While electro-depositing the copper foil on the cathode roller, a uniform layer of lead will be deposited on the surface of the anode plate. Utilize the lead deposited on its surface to protect the coating on the surface of the anode plate, maintain the uniformity of current transmission between the anode plate and the cathode roller, ensure the uniform deposition of the copper foil, and reduce the water ripple defects of the copper foil.

[0015] Optionally, the inhibitor PEG in Step 4 is set to 5 - 30 mg / L.

[0016] Optionally, the control current of the DC power supply in Step 6 is 35000 A, and the linear velocity is 9.455 m / min.

[0017] The present invention provides a production process for effectively improving the water ripples of electrolytic copper foil, having the following beneficial effects:

[0018] This production process for effectively improving the water ripples of electrolytic copper foil, without affecting production efficiency and production stability, improves the uniformity of copper foil electro-deposition through simple operations, improves the water ripple defects of the copper foil, reduces the direct waste of copper foil caused by water ripple defects, and reduces time costs and production costs;

[0019] Protect the surface coating of the anode plate, extend the service life of the anode plate, reduce production costs; improve the quality stability of copper foil products, reduce problems occurring during the client's use process, and reduce the customer complaint rate; the straight waste meters of water ripples in 6μm ultra-thin copper foil are reduced from 1432m to 28m, and the service life of the anode plate is increased from 70 days to 187 days, greatly reducing the waste of production costs caused by water ripple defects. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic flow diagram of the invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0021] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments.

[0022] In the description of the present invention, unless otherwise specified, "a plurality of" means two or more; the orientation or positional relationship indicated by terms such as "upper", "lower", "left", "right", "inner", "outer", "front end", "rear end", "head", "tail", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. In addition, terms such as "first", "second", "third", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0023] In the description of the present invention, it should be noted that unless otherwise clearly specified and defined, the terms "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0024] Example 1: A production process for effectively improving the water ripples of electrolytic copper foil, a copper sulfate electrolyte solution kept at a constant temperature at 50 - 55°C, with a sulfuric acid concentration of 100 g / L, a copper concentration of 95 g / l, a chloride ion concentration of 16 mg / L, a lead ion concentration of 1 mg / L, and a combined additive of 10 mg / L PEG, collagen, and SPS. The straight waste meters of water ripples in the 6μm ultra-thin copper foil produced in this example are 576m, and the service life of the anode plate is 100 days.

[0025] Example 2: A production process for effectively improving the water ripples of electrolytic copper foil. The copper sulfate electrolyte is kept at a constant temperature of 50 - 55°C. In the copper sulfate electrolyte, the sulfuric acid concentration is 105 g / L, the copper concentration is 90 g / L, the chloride ion concentration is 18 mg / L, the lead ion concentration is 2 mg / L, and a combined additive of 20 mg / L PEG, collagen, and SPS is used. The number of meters of the 6μm ultra-thin copper foil scrapped due to straight water ripples produced in this example is 28 m, and the service life of the anode plate is 187 days.

[0026] Example 3: A production process for effectively improving the water ripples of electrolytic copper foil. The copper sulfate electrolyte is kept at a constant temperature of 50 - 55°C. In the copper sulfate electrolyte, the sulfuric acid concentration is 110 g / L, the copper concentration is 85 g / L, the chloride ion concentration is 20 mg / L, the lead ion concentration is 4 mg / L, and a combined additive of 15 mg / L PEG, collagen, and SPS is used. The number of meters of the 6μm ultra-thin copper foil scrapped due to straight water ripples produced in this example is 150 m, and the service life of the anode plate is 121 days.

[0027] Control Group 1: The copper sulfate electrolyte is kept at a constant temperature of 50 - 55°C. In the copper sulfate electrolyte, the sulfuric acid concentration is 95 g / L, the copper concentration is 85 g / L, the chloride ion concentration is 14 mg / L, the lead ion concentration is 0 mg / L, and a combined additive of 15 mg / L PEG, collagen, and SPS is used. The number of meters of the 6μm ultra-thin copper foil scrapped due to straight water ripples produced in this control group is 1432 m, and the service life of the anode plate is 70 days.

[0028] Control Group 2: The copper sulfate electrolyte is kept at a constant temperature of 50 - 55°C. In the copper sulfate electrolyte, the sulfuric acid concentration is 115 g / L, the copper concentration is 90 g / L, the chloride ion concentration is 16 mg / L, the lead ion concentration is 0 mg / L, and a combined additive of 20 mg / L PEG, collagen, and SPS is used. The number of meters of the 6μm ultra-thin copper foil scrapped due to straight water ripples produced in this control group is 1068 m, and the service life of the anode plate is 84 days.

[0029] Conclusion: This production process, without affecting production efficiency and production stability, improves the uniformity of copper foil electrodeposition through simple operations, improves the water ripple defects of copper foil, reduces the direct scrapping of copper foil caused by water ripple defects, and reduces time costs and production costs;

[0030] Protect the surface coating of the anode plate, extend the service life of the anode plate, and reduce production costs; improve the quality stability of copper foil products, reduce problems occurring during the client's use process, and reduce the customer complaint rate; the number of meters of the 6μm ultra-thin copper foil scrapped due to straight water ripples is reduced from 1432 m to 28 m, and the service life of the anode plate is increased from 70 days to 187 days, greatly reducing the production cost waste caused by water ripple defects.

[0031] The above are only the preferred specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, makes equivalent substitutions or changes, and all should be covered within the protection scope of the present invention.

Claims

1. A production process for effectively improving water ripples in electrolytic copper foil, characterized in that: The specific steps include: Step 1: Add copper wire, concentrated sulfuric acid and lead sulfate solution into the copper dissolving tank and mix them thoroughly; Step 2: Prepare a copper sulfate electrolyte with a sulfuric acid concentration of 90-120 g / L, a copper concentration of 80-95 g / L, a chloride ion concentration of 10-20 mg / L, and a lead ion concentration of 1-5 mg / L; Step 3: Maintain the electrolyte concentration at a stable temperature of 50-55°C; Step 4: adding a combination additive of inhibitor PEG, brightener SPS and leveler collagen; Step 5: In a foil production machine with an iridium-plated titanium anode plate as an anode and a titanium roller as a cathode; Step 6: Under the action of a DC power supply, 6 μm ultra-thin copper foil is electroplated on a cathode roller; Step 7: While the cathode roller is electroplating copper foil, a uniform layer of lead will be deposited on the surface of the anode plate. The lead deposited on its surface will protect the coating on the surface of the anode plate, maintain the uniformity of current transmission between the anode plate and the cathode roller, ensure the uniform deposition of copper foil, and reduce the water ripple defects of the copper foil.

2. A production process for effectively improving water ripples in electrolytic copper foil according to claim 1, characterized in that: The inhibitor PEG in step 4 is set to 5-30 mg / L.

3. The production process for effectively improving water ripples of electrolytic copper foil according to claim 1, characterized in that: In step six, the control current of the DC power supply is 35000A, and the line speed is 9.455m / min.

4. The production process for effectively improving water ripples of electrolytic copper foil according to claim 1, characterized in that: described.

5. The production process for effectively improving water ripples of electrolytic copper foil according to claim 1, characterized in that: described.

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