CN115717255A - Zero-stress electrolytic metal foil preparation method, system used thereby and application of method - Google Patents

Abstract

The invention belongs to the field of electrochemistry, and in particular relates to a preparation method of zero-stress electrolytic metal foil, and the application of the system and method thereof. The method includes: 1) setting a movable conductive medium, the conductive medium can dynamically pass through the electrolyte, and when in the electrolyte, the conductive medium is electrically connected to the anode provided in the electrolyte, and the conductive medium is used as the cathode in the electrolyte. Carry out the electrodeposition preparation of metal foil on the conductive medium to obtain the conductive medium-metal foil; 2) separate and remove the conductive medium-metal foil by phase change and/or chemical method and/or dissolution and/or expansion and contraction Conductive medium composition, that completes zero-stress preparation of electrolytic metal foil. Through the improvement of the process, the present invention can effectively control the preparation thickness and size specifications of the electrolytic metal foil and carry out continuous production, has strong applicability, high yield rate of products, and high economic benefits.

Description

A zero-stress electrolytic metal foil preparation method, and the system and method used therein application

technical field

The invention belongs to the field of electrochemistry, and in particular relates to a preparation method of zero-stress electrolytic metal foil, and the application of the system and method thereof.

Background technique

Metal foil is a thin sheet metal product, such as copper foil, which is usually made of copper plus a certain proportion of other metals. Generally, the copper content of commercially available copper foils is 80wt% or 90wt%, corresponding to 80wt% and 90wt% respectively. In the past market environment, its most widely used is as a decorative material, because it has low surface oxygen characteristics, can be attached to various substrates, such as metals, insulating materials, etc., and has a wide temperature range.

However, with the development of metal foil, various demands have been generated in the market. For example, in the field of copper foil, the developed high-purity electronic-grade copper foil with copper content ≥ 99.7wt% is also widely used in electronic equipment due to its excellent conductivity and electromagnetic shielding effect. Electronic grade copper foil is one of the basic materials of the electronics industry. With the rapid development of the electronic information industry, the use of electronic grade copper foil is increasing. The products are widely used in industrial calculators, communication equipment, QA equipment, lithium-ion copper foil , Copper foil storage battery, civil TV, video recorder, CD player, copier, telephone, heating and cooling air conditioner, electronic components for automobiles, game consoles, etc. There is an increasing demand for electronic-grade copper foil, especially high-performance electronic-grade copper foil, in domestic and foreign markets.

Prior to this, the inventor has carried out corresponding research and development on the metal foil preparation process, and has jointly applied for three invention patent applications, CN202111335008. In the patent application, the effective and non-destructive preparation of ultra-thin, ultra-high-purity metal foil has been realized, which can be very suitable for the preparation of high-standard ultra-thin special metal foil. However, in the actual industrialization process, it is also found that when the above three patented technologies are used for the production and preparation of large-thickness and large-scale metal foils, it is very prone to problems such as wrinkles and fractures. For 1-3μm or even below 1μm Metal foils such as small-sized ultra-thin special copper foils have good production adaptability, can achieve good quantitative production and generate huge economic benefits, but for the continuous production of metal foils with a thickness of 3-8 μm that is conventionally required, especially for large The production adaptability of standard metal foil rolls is poor, it cannot be realized effectively, and the cost is relatively high.

However, in the prior art, there are also obvious defects in the production of electrolytic metal foil with a thickness of 4-6 μm, that is, the existing electrolytic method deposits the metal foil directly on the cathode roll or the intermediate material on the surface of the cathode roll, but its When peeling off, only the metal foil is peeled off, so the metal foil is also very easy to tear, resulting in poor quantitative production effect. The current existing electrolysis process can only be basically applicable and suitable for metals above 6 μm even in high-standard fine-grained production. Foil rolls are produced continuously, and even most equipment that cannot achieve high-precision and fine-grained preparation can only prepare thick copper foil above 18 μm.

Contents of the invention

In order to solve the problem that the existing electrolytic metal foil preparation process is subjected to a large stress when the metal foil is peeled off, causing it to be easily broken and damaged, and the remaining existing processes cannot be effectively adapted to the efficient and non-destructive continuous production of 3-6 μm metal foil. , the invention provides a zero-stress electrolytic metal foil preparation method, its application and the obtained metal foil.

The primary purpose of the present invention is to:

1. It can be effectively adapted to the electrolytic preparation of any existing metal foil;

2. It can realize zero-stress peeling of metal foil and improve the yield rate of metal foil;

3. It can realize the continuous production of 2-8μm metal foil;

4. Reduce the production cost of high-quality metal foil;

Fifth, it can independently realize the control and adjustment of the microscopic morphology and texture coefficient of the metal foil surface.

In order to achieve the above object, the present invention adopts the following technical solutions.

A zero-stress electrolytic metal foil preparation method,

The methods include:

1) A movable conductive medium is provided, and the conductive medium can dynamically pass through the electrolyte, and when in the electrolyte, the conductive medium is electrically connected to the anode provided in the electrolyte, and the conductive medium is used as the cathode to carry out metallurgy on the conductive medium. Electrodeposition preparation of foil to obtain conductive medium-metal foil;

2) Separating and removing the conductive medium component in the conductive medium-metal foil by means of phase change and/or chemical method and/or dissolution and/or expansion and contraction method, that is to complete the zero-stress preparation of electrolytic metal foil.

Preferably, the movable conductive medium in step 1) enters the electrolyte solution in the form of strips and/or target-shaped sheets and/or shaped and solidified slurry.

Preferably, the shaped and solidified slurry is filled into a specific carrier for gravity leveling and/or shape pressing, and then used as a conductive medium after curing.

As a preference,

Step 1) The electrolyte contains a soluble metal salt of the target metal foil component;

Step 1) The anode is an insoluble anode.

For the method of the present invention, its core is to completely avoid the stripping process in the traditional preparation method, and to ensure a high degree of flexibility in the implementation and use of the scheme. And the core of the technical concept of the present invention is also significantly different from the previous basic scheme. In the three atomic method (or gas phase method) schemes of CN202111335008.X, CN202111335007.5 and CN202111335012.6 developed by the inventor of the aforementioned application , its core lies in gravity peeling, which realizes the detachment and acquisition of metal foil through gravity, so it is actually more suitable for sheet preparation within a certain specification, and because it is prepared by the atomic deposition method of evaporation deposition, it achieves ultra-high precision. At the same time, the preparation also limits the size and thickness of its production, and increases the difficulty and cost of the process. The core lies in the preparation, elimination and gravity peeling of the middle layer, so as to realize the spontaneous detachment of the metal foil. The core of this application is to select an appropriate conductive medium, use the conductive medium as a template to carry out electrolysis first, and then use the method of lost foam to realize the removal of the conductive medium, completely avoiding the process of "stripping", while the atomic method is still Without breaking away from the "stripping" process, it provides a novel peeling form and combines the vapor deposition method to realize the effective and non-destructive preparation of ultra-thin metal foil, but the metal foil is still subject to a large peeling stress. The present invention can completely avoid the peeling stress. Achieve complete and non-destructive media-foil separation.

Whether the stress effect is on the preparation of ultra-thin metal foil or the preparation of large-scale metal foil, its influence is very significant. The original gas phase method reduces the stress of metal foil and realizes the preparation of ultra-thin special metal foil with a specific deposition form, but it cannot overcome the influence of gravity stress on large-scale metal foil and cannot overcome the deposition method used. Regarding the limitation of thickness, the present invention realizes continuous production with complete zero stress and realizes continuous production with controllable thickness in combination with a mature electrolysis process.

In addition, the method of the present invention also integrates various technical advantages, such as combining the advantages of low cost, high efficiency and simplicity of electrolysis, and the advantages of controllable microscopic morphology brought by conductive media. The galvanized aluminum foil with the structure is used as the conductive intermediate layer, and a metal foil with ultra-thin thickness of 2-6 μm and super-hydrophobic properties can be realized.

In addition, in the case of the effective combination of various technologies, the selection of conductive media has been greatly expanded. Because the thickness of the conductive media is thinner, it is even possible to select some organic film materials as the conductive media, so that low conductivity is no longer used as electrolytic deposition. The technical obstacle of metal foil, and the present invention can realize the control of the thickness of the electrolytic metal foil through the stroke control, travel speed control, current density control, etc. of the conductive medium in the electrolyte, and can even realize the preparation of multiple foils in one pass, which greatly improves the Preparation efficiency and preparation effect.

A zero-stress electrolytic metal foil system,

The system is used for electrodeposition of a conductive medium, which includes a deposition device and a post-processing device;

The deposition device includes an electrolytic cell, a cathode, an anode and a power supply;

The cathode, anode and power supply are electrically connected;

The electrolytic cell is used to accommodate the electrolyte, the anode is arranged in the electrolytic cell, the cathode is electrically connected to the conductive medium, and the conductive medium is used as an extension of the cathode, so that the conductive medium exists as a cathode in the electrolytic cell for electrodeposition;

The post-processing device is used to remove the conductive medium, which includes a solvent pool and/or a heating device and/or a refrigeration device and/or a combustion device and/or an atmosphere treatment device.

As a preference,

The system also includes a conveyor for enabling transport of the conductive medium.

As a preference,

The system also includes a pre-processing device;

The pre-treatment device loads the conductive medium on the carrier and/or surface treatment of the conductive medium;

The carrier moves under the drive of the conveying device, and the conductive medium is carried through the deposition device and the post-processing device in sequence.

Preferably, the pre-treatment device includes a spraying device and/or a brushing device and/or a solvent pool and/or a heating device and/or a cooling device and/or a UV curing device and/or a spraying device.

For the system used in the present invention, the core part is the deposition device and the post-processing device, and due to the high flexibility of the method scheme of the present invention, free adjustment and selection can be carried out according to requirements during actual use, so the present invention only Describe the core and irreplaceable parts in detail.

As for the deposition device, it is actually closer to the conventional electrodeposition device, but the most different point is that the conventional electrodeposition device needs to ensure that at least half of the cathode is immersed in the electrolyte, and the formed electrolytic metal foil is directly in the It is obtained by peeling off the cathode, while the present invention uses the conductive medium as an extension of the cathode, actually as a "second cathode" that is "constantly moving and can be consumed", so the cathode can completely leave the electrolyte and preferably completely leave the electrolysis Liquid, even the cathode can be regarded as a conductive joint in essence, its function is only to conduct electricity and distinguish the anode, which also prevents the cathode from being placed in the electrolyte and the deposition of metal ions on the surface of the cathode, which leads to deposition on the surface of the cathode The continuous accumulation of substances changes the progress of the conductive medium, etc.

In addition, the post-processing device is more flexibly selected and used according to the material of the conductive medium. For example, in the case of conductive carbon cloth as the conductive medium, the low oxygen partial pressure can be controlled by the atmosphere treatment device, and the incomplete combustion can be carried out in conjunction with the combustion device, which not only ensures the complete removal of the carbon cloth components, but also the CO gas formed by the incomplete combustion. Avoid the oxidation of the metal foil, and at the same time relieve the internal stress of the metal foil to a certain extent. Another example is the PAN/PMMA conductive film, which can be quickly dissolved and removed by solvents, and can effectively protect and clean the metal foil. For example, when copper alloy and other alloy strips are used as the conductive medium to prepare metal foil, reasonable settings can make the linear thermal expansion coefficients of the alloy strip and the metal foil have a huge difference, and even separation can be achieved through appropriate alternating cold and heat treatment. Effectively improve the internal stress of metal foil. It can be seen that for the technical solution of the present invention, through the reasonable application of known material properties, on the basis of the core of the technical concept of the present invention, it is possible to use any combination of various methods to realize the non-destructive separation of metal foil.

For the transmission device, it is also free to choose according to the conductive medium and carrier. For example, a strip-shaped conductive medium can be simply driven by a roller to be transported.

The pre-processing device is another feature of the system of the present invention. Because some conductive media are not easy to prepare in large areas, use or have insufficient strength, or have special requirements for the shape of metal foil, etc., they need to be used with carriers, so through pre-processing The device prepares the conductive medium on the carrier first, and then removes the conductive medium on the carrier through the post-processing device to separate and obtain the metal foil. The preparation process with the carrier is the closest to the previously developed scheme on the surface, but it should be noted that this scheme of the present invention is only used for the preparation of metal foils that need to achieve a specific shape or specific shape, that is, through the complex method The microscopic topography of the conductive medium surface with insufficient strength is "symmetrically imprinted" on the surface of the metal foil to realize the regulation of the microscopic topography of the metal foil, or it is necessary to realize the preparation of a regular hexagonal metal foil in a targeted manner, which is still a An improvement scheme that is optimized in various aspects in combination with the technical scheme of the present invention. The above-mentioned effects cannot be achieved by atomic deposition methods.

Another purpose of the pre-treatment device is to treat the surface of the conductive medium, such as controlling the texture of the metal foil through the additive treatment, and further enhancing the preparation effect of the metal foil of the present invention through the additive.

Application of a zero-stress electrolytic metal foil preparation method,

The method is used for the production of metal foil with a thickness dimension ≥ 2 μm, and/or for the production of large-sized metal foil with a length dimension ≥ 3 m and a width dimension ≥ 1.2 m, and/or for continuous production of metal foil rolls.

In specific production tests, the technical solution of the present invention can realize the continuous production and preparation of ultra-long and ultra-large metal foil rolls. The metal foil contained in the metal foil roll has a thickness of 4.2 μm, a width of 1.35 m, and a total length of 220 m. It can be seen that it can actually be used in the quantitative production of super-sized metal foils. Meet industrial maturity standards.

The beneficial effects of the present invention are:

Through the improvement of the process, the present invention can effectively control the preparation thickness and size specifications of the electrolytic metal foil and carry out continuous production, with strong applicability, high product yield, and high economic benefits. It can effectively control the surface morphology of the metal foil, and has the advantages of wide application range, strong process flexibility, and high industrialization maturity.

Description of drawings

Fig. 1 is the system schematic diagram of embodiment 1 of the present invention;

Figure 2 is one of the partial structural schematic diagrams of the deposition device in Example 1 of the present invention;

Fig. 3 is one of the partial structural schematic diagrams of the deposition device in Example 1 of the present invention;

FIG. 4 is one of the partial structural schematic diagrams of the deposition device in Embodiment 1 of the present invention;

5 is a schematic diagram of a conductive carrier according to Embodiment 3 of the present invention;

Fig. 6 is a schematic diagram of the system of Embodiment 3 of the present invention;

Fig. 7 is a schematic diagram of the system of Embodiment 4 of the present invention;

Fig. 8 is a partial structural schematic diagram of the deposition device of Embodiment 4 of the present invention;

Fig. 9 is a schematic diagram of the system of Embodiment 5 of the present invention;

FIG. 10 is a partial structural schematic diagram of a deposition device according to Embodiment 5 of the present invention.

In the figure: 100 conveying device, 200 pre-processing device, 201 treatment liquid nozzle, 202 ink dropper, 203 UV lamp, 204 medium material nozzle, 205 cold air cylinder, 300 deposition device, 301 cathode, 302 anode, first anode 302a, the first Two anodes 302b, 303 power supply, 304 electrolytic cell, 3041 main tank, 3042 auxiliary tank, 3043 through tank, 305 deposition roller, 306 scraper, 400 post-processing device, 401 flame nozzle, 402 box-type atmosphere furnace, 4021 intake pipe, 4022 outlet pipe, 403 spray device, 500 reel, A conductive medium, A01 conductive copper alloy strip, A011 mold groove, A012 insulating layer, B medium-foil, B01 conductive medium layer, B02 foil layer, C product foil, C01 The first electrolytic copper foil, C02 second electrolytic copper foil.

Detailed ways

In the following, the present invention will be further clearly and detailedly described in conjunction with specific embodiments and accompanying drawings. Those skilled in the art will be able to implement the present invention based on these descriptions. In addition, the embodiments of the present invention referred to in the following description are generally only some embodiments of the present invention, not all of them. Therefore, based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

In describing the present invention, it is to be understood that the terms "thickness", "upper", "lower", "horizontal", "top", "bottom", "inner", "outer", "circumferential" etc. The indicated orientation or positional relationship 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 referred device or element must have a specific orientation, or in a specific orientation. construction and operation, therefore, should not be construed as limiting the invention. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined, and "several" means one or more.

In the present invention, unless otherwise clearly specified and limited, terms such as "installation", "connection", "connection" and "fixation" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection , or integrated; can be mechanically connected, can also be electrically connected or can communicate with each other; can be directly connected, can also be indirectly connected through an intermediary, can be the internal communication of two components or the interaction relationship between two components, Unless expressly defined otherwise. Those of ordinary skill in the art can understand the specific meanings of the above terms in the present invention according to specific situations.

Unless otherwise specified, the raw materials used in the examples of the present invention are commercially available or available to those skilled in the art; unless otherwise specified, the methods used in the examples of the present invention are all methods mastered by those skilled in the art.

Example 1

The technical scheme of the present invention is illustrated by a system with strong universality and high industrialization maturity. As shown in the schematic diagram of FIG. device 400;

This set of system is in good condition from January 2022 to May 2022, and it is specifically used for the preparation of oxygen-free electrolytic copper foil; The electric roller is used as the conveying device 100 for conveying and conveying. The conductive medium A used in the present invention is a commercially available PU conductive film roll, and the size specification is 1.2m * 60m; under the action of the conveying device 100, the conductive medium A (PU conductive film) is first sent to the pre-processing device 200, in the pre-processing device 200, the present embodiment is provided with an atomizing spray head as the treatment liquid spray head 201, and the treatment liquid spray head 201 evenly sprays 50wt% polycarbonate on the deposition surface of the conductive medium A film. The ethyleneimine aqueous solution is controlled by the feeding rate of the conveying device 100 and the flow rate of the treatment liquid nozzle 201, so that the spraying amount on the deposition surface of the conductive medium A film is about 12-15g/m ² , and then driven by the conveying device 100 Next, the thin film of conductive medium A enters the deposition device 300. As can be seen from FIG. Bonding, when the conductive medium A film enters the electrolyte of the electrolytic cell 304, it can be used as an extension of the cathode 301 to form electrodeposition;

The anode 302 is a commercially available graphite anode 302, which is arranged at the bottom of the electrolytic cell 304. The power supply 303 is a thyristor power supply 303 purchased from SanRex. The electrolyte solution is injected into the electrolytic cell 304. The electrolyte solution in the electrolytic solution is 280-320g /L copper sulfate pentahydrate solution, which also contains 120g/L of sulfuric acid and 10mg/L of gelatin, and the electrolytic solution is dynamically controlled by adding copper sulfate pentahydrate to the copper ion concentration;

When the conductive medium A film enters the electrolytic cell 304, the deposition surface faces downward and faces the anode 302. After the power supply 303 is turned on, the electrolytic cell 304 works to realize electrodeposition on the deposition surface of the conductive medium A film, and prepare electrolytic copper foil. Then, after the preparation of the electrolytic copper foil is completed on the deposition surface of the conductive medium A film, the medium-foil B (that is, the PU conductive film medium-electrolytic copper foil composite) is sent out of the deposition device 300 through the conveying device 100, and sent to the post-processing device 400 middle;

Specifically, the partial structural schematic diagrams of the constructed deposition apparatus 300 except the power supply 303 are shown in FIG. 2, FIG. 3 and FIG. Effective deposition on the film deposition surface of conductive medium A forms medium-foil B made of conductive medium A and product foil C (copper foil) after deposition; in this embodiment, the post-processing device 400 consists of an atmosphere treatment device Constituted with a combustion device, the atmosphere treatment device is a box-type atmosphere furnace 402, the combustion device is a flame nozzle 401 and the flame nozzle 401 extends into the box-type atmosphere furnace 402, and the box-type atmosphere furnace 402 is provided with an air inlet pipe 4021 And the air outlet pipe 4022, the air inlet pipe 4021 is sent into the hypoxic partial pressure gas, and the oxygen concentration in the gas is less than or equal to 14% VOL. In this embodiment, the oxygen concentration in the controlled gas is 12-14% VOL. Combustion gas, the inlet pipe 4021 is arranged at the top of the box-type atmosphere furnace 402, and the outlet pipe 4022 is arranged at the bottom of the box-type atmosphere furnace 402, forming an environment that is more conducive to deoxidizing the electrolytic copper foil and avoiding oxidation. The conductive medium A film layer of medium-foil B is continuously sprayed to burn and remove the PU film, the gas flow rate of the inlet pipe 4021 and the gas flow rate of the outlet pipe 4022 are controlled, and the exhaust gas of the outlet pipe 4022 is detected to ensure Contain the CO of at least 2%VOL in the output gas, to ensure incomplete combustion in the box-type atmosphere furnace 402, but need to ensure the complete combustion removal of PU film, obtain product foil C (being metal foil, anaerobic) after this process Copper foil), the obtained product foil C is then driven by the conveying device 100 to the outside of the post-processing device 400 and stored in rolls by means of the reel 500 to obtain an oxygen-free copper foil product.

The oxygen content of the oxygen-free copper foil product was characterized, and the characterization results showed that the oxygen content in the prepared product foil C was 3.1-3.5ppm, which met the standard of oxygen-free copper foil, and the oxygen content was extremely low;

In addition, samples were taken from the intermediate product of medium-foil B, and the copper foil was peeled off to characterize its oxygen content. The characterization results showed that its oxygen content was 2.8-3.2. It can be seen that in the subsequent post-treatment process, it did not increase significantly oxygen content.

In addition, in this embodiment, the current density is controlled to be 3A/dm ² , the temperature of the electrolyte is 50°C, and the load time of the conductive medium A is controlled by the transmission device 100 from entering the electrolyte to when the electrolyte is discharged. The load time in this embodiment is 4 minutes , the thickness of the obtained product foil C is 3.3 μm, and its tensile strength is characterized, and the characterization results show that its tensile strength can reach 462 MPa, which has very excellent tensile properties.

Example 2

On the basis of Example 1, the electrodeposition parameters of the product and some variable parameters were adjusted and tested, and the product foil C was characterized, and the results shown in the following table were obtained. Among them, when the thickness of the product is characterized, when the maximum thickness (δ _max ) and the minimum thickness (δ _min ) meet δ _max -δ _min ≤ 0.03μm, the average thickness of ten measurements is recorded; if not, the maximum value is recorded and the minimum interval. Product characterization accuracy is 0.05μm.

current density load time other variables Product thickness tensile strength 2A/dm² 3min none 1.55μm 371MPa 2A/dm² 4min none 2.1μm 400MPa 2A/dm² 5min none 2.65μm 429 MPa 2A/dm² 6min none 3.2μm 460MPa 3A/dm² 3min none 2.4μm 413 MPa 3A/dm² 4min none 3.3μm 462 MPa 3A/dm² 5min no pretreatment 4.0μm 407MPa 3A/dm² 6min none 4.8μm 539MPa 4A/dm² 3min none 3.2μm 455MPa 4A/dm² 4min none 4.3μm 516MPa 4A/dm² 5min none 5.35μm 561MPa 4A/dm² 6min none 6.4μm 620MPa 5A/dm² 3min none 4.0μm 492 MPa 5A/dm² 4min none 5.3μm 566MPa 5A/dm² 5min none 6.8μm 639 MPa 5A/dm² 6min none 7.9μm 663MPa 3A/dm² 4min no pretreatment 3.3μm 372MPa

Each of the above-mentioned test groups tried to produce 2 rolls of copper foil, with a width specification of 0.8m and a length of 62m. Except that the copper foil obtained by the 2A/dm ² /3min test group had certain wrinkles, the copper foil produced by the other test groups No damage or wrinkle.

It can be seen from the above table that for the technical solution of the present invention, the thickness of the product foil C can be controlled by adjusting the current density and loading time, and there is a certain coefficient correlation. Based on previous tests, the thickness of the manufactured product foil C can be controlled by empirical formulas in actual production. The specific empirical formula is as follows:

d=A+B×J+C×T

In the formula: d is the thickness of the product foil C, the unit is μm, A, B, and C are empirical coefficients, A is affected by the composition of the metal foil, and the unit is μm, B and C are affected by the distance between the anode 302 and the deposition surface, and the location of the anode 302 , the travel route of the conductive medium A deposition surface and other factors, the unit of B is μm·dm ² /A, the unit of C is μm/min, J is the current density, the unit is A/dm ² , T is the load time, the unit is min.

The above formula can be calculated after three trial productions to obtain the empirical coefficients of A, B, and c, and then simply fit to obtain the reference formula for actual production to guide actual production. The more trial production times, the higher the accuracy of the reference formula.

In addition, it can be seen from other variable tests that for the technical solution of the present invention, the pretreatment device 200 does not affect the thickness of the product foil C produced, that is, the treatment agent in this embodiment has no obvious influence on the thickness of the copper foil, but for the copper foil The mechanical properties of the foil have a more significant effect. For example, in this embodiment, the tensile strength of copper foil can be effectively improved by spraying and using polyethyleneimine. It can be seen that the pretreatment device 200 has a good performance in improving the performance of copper foil. The pretreatment scheme in this embodiment is based on industry-university research. 202110636882.0, 202110638177.4 and other technical adjustments disclosed in the cooperation project results.

Comparative example 1

Based on the technical solution of embodiment 1, there are only the following differences:

Through the conveying device 100, the medium-foil B produced by the deposition device 300 is sent to a fully automatic peeling machine (commercially available: Maidap fully automatic copper foil tearing machine), and the conductive medium A and the product foil C (copper foil) are separated. tear-off separation process.

Compared with the technical solution of Example 1, the time required for the separation and preparation of 1.2m×60m copper foil by the post-processing device 400 in Example 1 was 26 minutes, and the time required for the peeling and separation treatment of Comparative Example 1 was 2h 11min by using a fully automatic tearing machine. The efficiency can be seen. There is a huge difference in . In addition, the copper foil of the post-processing device 400 in Example 1 has no damage or wrinkle in the whole process, and the product yield rate reaches 100%. However, in Comparative Example 1, the copper foil was slightly damaged in 6 places and there were several wrinkles when the automatic tearing machine was used. Characterize the tensile strength of the copper foil prepared by the two. The characterization result of Example 1 is 462MPa, while the characterization result of Comparative Example 1 is only about 417MPa. It can be seen that the peeling treatment will have a certain adverse effect on the mechanical properties of the copper foil. , and it is easy to cause damage to the copper foil, and the processing efficiency is low. It can be seen that the technical solution of the present invention has obvious advantages compared with the conventional electrolytic metal foil preparation solution.

Comparative example 2

Based on the previously developed atomic method scheme, a horizontal comparative preparation test was carried out with the technical scheme of the present application.

Based on the specific scheme of Example 3 in the 202111335007.5 technical scheme, by adjusting the vapor deposition time to control the thickness of the atomic layer (copper foil), respectively prepare copper foils with a thickness of 1.2 μm, 3.2 μm and 6.8 μm and a size specification of 0.8m×1.0m Sheets, and continuous production of foil rolls with a thickness of 3.2 μm and a size of 0.6m×22m.

Based on the technical solution of Example 1, a foil roll with the same thickness of 3.2 μm and a size of 0.6 m×22 m was produced without pretreatment.

Example 3

Build a production system for metal foil:

The conductive copper alloy strip A01 is used as the conductive carrier, and the thickness of the conductive copper alloy strip A01 is 2.2cm, which has good flexibility and conductivity;

Specifically, as shown in Figure 5, a die groove A011 with a size of 0.8m × 1.0m is opened on one side of the conductive copper alloy strip A01 (C17000 grade beryllium copper alloy strip), and the conductive copper alloy strip A01 has a mold groove A011 on one side Perform insulation treatment to form insulation layer A012, and the side wall surface of mold cavity A011 is also subjected to insulation treatment to form insulation layer A012;

The mold cavity A011 is filled with UV curable conductive ink to the bottom of the mold cavity A011 that can be leveled by gravity flow. The UV curable conductive ink in this embodiment is commercially available and purchased from Yuxi New Materials;

The overall system is shown in Figure 6, including the same motorized roller as in Embodiment 1 as a conveying device 100 for conveying a conductive copper alloy strip A01 as a conductive carrier;

The conductive copper alloy strip A01 first enters the pre-processing device 200. For the present embodiment, the pre-processing device 200 is provided with an ink dropper 202 and a UV lamp 203. The UV curable conductive ink is dripped into the tank A011. With the conveying process of the conductive copper alloy strip A01, the gravity leveling is realized before reaching the irradiation range of the UV lamp 203, and then cured by UV, etc., as shown in the partial enlarged view in Figure 6. The conductive medium A film (UV curable conductive ink film) is formed in the mold cavity A011, and then enters the deposition device 300 under the drive of the conveying device 100. The deposition device 300 of this embodiment is similar to that of Embodiment 1, including a cathode 301, an anode 302, electrolytic cell 304 and power supply 303;

The cathode 301 is arranged on the outside of the electrolytic cell 304. The back side of the conductive copper alloy strip A01 (the side with the mold groove A011 is the front side, and the opposite side is the back side) first passes through the cathode 301 and is bonded to the cathode 301. When the conductive copper alloy strip A01 After the strip A01 enters the electrolytic solution of the electrolytic cell 304, the conductive copper alloy strip A01 and the UV-cured conductive ink film (conductive medium A film) can form electrodeposition as an extension of the cathode 301;

The anode 302 is a commercially available graphite anode 302, which is arranged at the bottom of the electrolytic cell 304. The power supply 303 is a thyristor power supply 303 purchased from SanRex. The electrolyte solution is injected into the electrolytic cell 304. The electrolyte solution in the electrolytic solution is 280-320g /L copper sulfate pentahydrate solution, which also contains 120g/L of sulfuric acid and 10mg/L of gelatin, and the electrolytic solution is dynamically controlled by adding copper sulfate pentahydrate to the copper ion concentration;

When the conductive medium A film enters the electrolytic cell 304, the deposition surface faces downward and faces the anode 302. After the power supply 303 is turned on, the electrolytic cell 304 works to realize electrodeposition on the deposition surface of the conductive medium A film, and prepare electrolytic copper foil. Then, after the preparation of the electrolytic copper foil is completed on the deposition surface of the conductive medium A film, the conductive copper alloy belt A01 loaded with the medium-foil B (that is, the UV curable conductive ink film-electrolytic copper foil composite) is sent out of the deposition device through the conveying device 100 300, sent to the post-processing device 400;

The post-processing device 400 includes a solvent pool, the solvent pool cooperates with the heating device to heat the solvent in the solvent pool, and the acetone-cyclohexanone solution is perfused in the solvent pool, wherein acetone and cyclohexanone are in a volume ratio of 1:3 Mixing, the heating device heats the acetone-cyclohexanone solution in the solvent pool to 85°C, and puts the conductive copper alloy strip A01 loaded with the medium-foil B into the solvent pool for hot-dip treatment, during which the conductive medium The A film is partially softened and dissolved, and the viscosity is significantly weakened, so that the product foil C on the surface of the conductive medium A film falls off into the solvent pool;

The bottom of the solvent pool is sloped and a diversion opening is provided at the lower slope end. The acetone-cyclohexanone solution flows out from the diversion opening and drives the shedding electrolytic copper foil to leave the solvent pool to recycle the product foil C. The recovery can be done first Pre-store all the solvent and electrolytic copper foil in the recovery bucket and cool down to normal temperature to remove the electrolytic copper foil. You can also adopt a more optimal solution as in this example. This example uses a slanting plate separator so that the electrolytic copper foil can The sloping plate of the plate separator is trapped by surface tension and friction, while the solvent part flows to the bottom of the slope for separation. The use of the sloping plate separator is less likely to cause damage to the electrolytic copper foil than the recovery method of recycling barrels, especially for ultra- For low-thickness copper foil, the salvage process will easily lead to a certain degree of bending or wrinkling of the electrolytic copper foil. In addition, this embodiment is equipped with a liquid pump in conjunction with the inclined plate separator, and the liquid pump pumps the solvent obtained after separation into the to be used in the solvent pool; and as can be seen from FIG. 6, the conductive medium A will also be removed in a large amount in the solvent pool, and the conductive copper alloy strip A01 can enter the pretreatment device 200 again under the drive of the conveying device 100, Realize the single strip recycling of conductive copper alloy strip A01; although the post-processing device 400 cannot completely and effectively remove and clean the conductive medium A film component (UV cured conductive ink film), due to the characteristics of the pre-processing device 200 , UV curable conductive ink will go through the gravity leveling process after dripping into the mold cavity A011, which can ensure the flatness of the formed conductive medium A film within a certain period, and only need to clean the mold cavity A011 regularly, and the process cost is low , It can quickly build a system to realize the production and preparation of small and medium batches of electrolytic metal foil.

In addition, the pretreatment device 200 can also implement the conductive medium A loaded on the conductive copper alloy strip A01 in the form of a film, such as attaching the PU conductive film described in Embodiment 1, and at this time, the front surface of the conductive copper alloy strip A01 is completely oxidized Insulation treatment, and combined with the thermal expansion characteristics of the conductive copper alloy strip A01, the post-processing device 400 is firstly equipped with a heating device, a refrigeration device, an atmosphere treatment device and a combustion device, and the conductive medium A is first realized by the expansion and contraction method through the heating device and the refrigeration device. Separation of thin film and conductive carrier, and then recycle medium-foil B to remove conductive medium A by using atmosphere treatment device and combustion device to realize effective preparation of metal foil. This method is suitable for smaller size, finer and more quantity requirements The preparation of small monolithic metal foils.

The metal foils (copper foils) produced in Example 3 and Comparative Example 2 were characterized and analyzed, as shown in the table below.

In addition, take ten pieces of single-piece foil (0.8m×1.0m single-piece foil) and divide it into a judgment area of 5×5cm. If there are bad spots (including deformation, obvious folds, scratches, holes, and obvious corrosion) in the judgment area traces, or dirt that is obviously difficult to remove, etc.), then it is judged that the area is damaged, and if it is at the boundary of several judgment areas, only one judgment area is damaged.

Use this to calculate the dead point rate. The results are shown in the table below.

In the table: the gas phase method is the method described in Example 3 in the technical scheme of 202111335007.5 (iodine intermediate layer), and the zero stress method is the method of the present invention.

It can be seen from the above table that the zero stress method itself has the advantage of electrolytically preparing copper foil compared with the vapor phase method. The texture characteristics of the electrolytic copper foil are better than those of the vapor deposition copper foil, and have a greater ( 220) crystal surface texture coefficient, so the tensile strength is higher than that of the gas phase method, that is, the mechanical properties are better. The content is lower. From the dead point rate data, it can be seen that the gas phase method has a lower dead point rate for the preparation of a single piece of metal foil within a certain specification, but once the long foil roll is prepared, the dead point rate rises sharply. The preparation of foil rolls does not have good applicability, and when the present invention prepares special ultra-thin (1.2 μm thickness) metal foils, the dead point rate rises to a certain extent, but it can be seen in conjunction with the comparative test of Example 2 that, The technical solution of the present invention basically has a good preparation effect on electrolytic metal foils with a thickness of more than 2 μm.

Example 4

The method and system described in the technical solution of the present invention can also realize the simultaneous preparation of single-system double-foil materials, and construct a double-foil system as shown in Figure 7;

The dual-foil system includes a conveying device 100, a deposition device 300 and a post-processing device 400;

As shown in Figure 7, under the action of the conveying device 100, the conductive medium A of this embodiment uses a low-melting point PU conductive film with a melting point ≤ 136°C, and the conductive medium A enters the deposition device 300, from Figures 7 and 8 It can be seen that the cathode 301 of the deposition device 300 of the system of this embodiment is arranged outside the electrolytic cell 304, and the conductive medium A film first passes through the negative electrode 301 and is attached to the negative electrode 301. When the conductive medium A film enters the electrolyte of the electrolytic cell 304 Electrodeposition can then be formed as an extension of the cathode 301;

Described anode 302 is commercially available graphite anode 302, and this system is double anode 302 systems, and first anode 302a is arranged on the bottom of electrolytic cell 304, and second anode 302b is arranged on the top of electrolytic cell 304, and first anode 302a and second anode 302b Facing the opposite sides of the conductive medium A respectively, the power supply 303 is a thyristor power supply 303 purchased from SanRex, and the electrolytic cell 304 is injected with an electrolyte, and the electrolyte in the electrolyte is a 280-320 g/L copper sulfate pentahydrate solution. It also contains 120 g/L of sulfuric acid and 10 mg/L of gelatin, and the concentration of copper ions in the electrolyte is dynamically controlled by adding copper sulfate pentahydrate;

When the conductive medium A film enters the electrolytic cell 304, the first deposition surface faces down and faces the first anode 302a, and the second deposition surface obliquely faces the second anode 302b. Electrodeposition is carried out on the two deposition surfaces of the film to prepare electrolytic copper foil. After the preparation of electrolytic copper foil is completed on the deposition surface of the conductive medium A film, the medium-foil B (i.e. the first electrolytic copper foil) is transported by the conveying device 100 C01-PU conductive film medium-the second electrolytic copper foil C02 complex) is sent out of the deposition device 300, and sent into the post-processing device 400;

The post-processing device 400 described in this embodiment is composed of an atmosphere treatment device and a spraying device 403, the atmosphere processing device is a box-type atmosphere furnace 402, and the spraying device 403 is arranged in the box-type atmosphere furnace 402 and installed in the box-type atmosphere furnace 402. Type atmosphere furnace 402 strip outlet side, to ensure that the medium-foil B enters the box-type atmosphere furnace 402 first after the atmosphere treatment and then through the spray device 403, the box-type atmosphere furnace 402 is provided with an inlet pipe 4021 and an outlet pipe 4022 , the air inlet pipe 4021 is fed into the heat protection gas, the heat protection gas controlled in this embodiment is nitrogen at 150°C, the gas outlet pipe 4022 is used to discharge gas and melted PU or PU particles, and the air inlet pipe 4021 is arranged in the box The top of the type atmosphere furnace 402 and the gas outlet pipe 4022 are arranged at the bottom of the box type atmosphere furnace 402, which is more conducive to the discharge of the melted PU or PU particles from the electrolytic copper foil. The zero-stress separation of the electrolytic copper foil C01 and the second electrolytic copper foil C02, and the spraying device 403 is beneficial to remove the residual molten polyurethane more thoroughly, and the liquid sprayed by the spraying device 403 is a ring heated to 135°C Hexanol and cyclohexanol have the characteristics of low volatility and high boiling point, and have good adaptability to the technical solution of the present invention, but due to their slight toxicity and slight irritation, attention should be paid to recovery and staff protection during use;

The obtained product foils C (the first electrolytic copper foil C01 and the second electrolytic copper foil C02 ) are jointly driven by the conveying device 100 to the outside of the post-processing device 400 and stored in two reels 500 respectively.

In addition, in this embodiment, the current density is controlled to be 2.5A/dm ² , the temperature of the electrolyte is 50°C, and the transmission device 100 is used to control the conductive medium A to calculate the load time from entering the electrolyte solution to the time it exits the electrolyte solution. The load time in this embodiment is 5min, the thickness of the obtained first electrolytic copper foil C01 was 3.8 μm, and its tensile strength was characterized. The tensile strength was characterized, and the characterization results showed that the tensile strength reached 369MPa.

In addition, the position of the first anode 302a and the second anode 302b relative to the conductive medium A, the travel distance of the conductive medium A in the electrolytic cell 304, etc. are controlled, so that the first electrolytic copper foil C01 and the second electrolytic copper foil C01 can be controlled. The simultaneous control of foil C02 thickness greatly improves the actual production and preparation efficiency, and can realize the simultaneous preparation of double foils in a single system simply and efficiently, which is also impossible for conventional electrolytic metal foil technology and gas phase metal foil preparation technology.

Example 5

The method described in the technical solution of the present invention can also be combined with a conventional metal foil electrolysis system to form a continuous tear-off type zero-stress electrolysis metal foil system as shown in Figures 9 and 10;

The continuous tear-off type zero-stress electrolytic metal foil system includes a conveying device 100, a deposition device 300 and a post-processing device 400; 302 and a power supply 303, and a specially set deposition roller 305 and a scraper 306;

Specifically, the deposition roller 305 is braked by a motor to rotate at a controlled speed, and it is preferably made of an insulating material and a scratch-resistant material. For example, in this embodiment, the deposition roller 305 is specifically made of wear-resistant corundum ceramics, which has High surface smoothness, high strength, high hardness, acid and alkali corrosion resistance, and the surface is not easy to deposit dirt, so it can be used as a good carrier for loading conductive medium A;

The anode 302 is a commercially available graphite anode 302, which is arranged at the bottom of the electrolytic cell 304. The power supply 303 is a thyristor power supply 303 purchased from SanRex. The electrolyte solution is injected into the electrolytic cell 304. The electrolyte solution in the electrolytic solution is 280-320g /L copper sulfate pentahydrate solution, which also contains 120g/L of sulfuric acid and 10mg/L of gelatin, and the electrolytic solution is dynamically controlled by adding copper sulfate pentahydrate to the copper ion concentration;

The electrolytic cell 304 described in this embodiment is a double-tank electrolytic cell 304, which has a main tank 3041 and an auxiliary tank 3042 respectively. concentration, a through groove 3043 is provided between the main tank 3041 and the auxiliary tank 3042 to communicate;

The cathode 301 used in this embodiment is a conductive cathode 301 roller, which can rotate freely and is close to the deposition roller 305. The minimum distance between the conductive cathode 301 roller and the deposition roller 305, that is, the thickness of the conductive medium A, is in the direction of rotation of the deposition roller 305. Above, the front end of the cathode 301 is provided with a pre-processing device 200, the pre-processing device 200 includes a dielectric material nozzle 204 and a cold air cylinder 205, and the dielectric material nozzle 204 sprays the conductive medium A material (melted PU masterbatch) on the deposition roller 305 Surface, after the cold air cylinder 205 blows and solidifies, it is pressed and flattened by the cathode 301 to form a thin film of conductive medium A, which is driven by the deposition roller 305 into the electrolyte of the electrolytic cell 304, and electrodeposited on the surface of the conductive medium A to form a medium-foil B;

The scraper 306 is arranged at the rear end of the deposition roller 305 in the direction of rotation, and the blade portion abuts against the surface of the deposition roller 305, which can be arranged symmetrically with the cathode 301, and arranged above the electrolyte, for scraping off and separating the medium- foil B and deposition roller 305;

The separated medium-foil B is driven by the conveying device 100 to the post-processing device 400;

In this embodiment, the post-processing device 400 is composed of an atmosphere treatment device and a combustion device, the atmosphere treatment device is a box-type atmosphere furnace 402, the combustion device is a flame sprayer 401 and the flame sprayer 401 extends to the box-type atmosphere furnace In 402, the box-type atmosphere furnace 402 is provided with an air inlet pipe 4021 and an air outlet pipe 4022, and the air inlet pipe 4021 is fed into a gas with a low oxygen partial pressure, and the oxygen concentration in the gas is ≤ 14% VOL. This embodiment controls the oxygen concentration in the passed gas It is 12～14% VOL, and described outlet pipe 4022 is used for getting rid of combustion gas, and described inlet pipe 4021 is arranged on the top of box-type atmosphere furnace 402, and outlet pipe 4022 is arranged on the bottom of box-type atmosphere furnace 402, forms more favorable electrolysis In an environment where the copper foil deoxidizes and avoids oxidation, the flame nozzle 401 is aimed at the film layer of the conductive medium A of the medium-foil B, and continuously sprays flames to burn and remove the PU film, and controls the gas flow rate of the inlet pipe 4021 and the gas flow rate of the outlet pipe 4022 The gas flow rate and the exhaust gas of the outlet pipe 4022 are detected to ensure that the outlet gas contains at least 2% VOL of CO, so as to ensure incomplete combustion in the box-type atmosphere furnace 402, but it is necessary to ensure the complete combustion and removal of the PU film. After this process, the product foil C (that is, metal foil, oxygen-free copper foil) is obtained, and the obtained product foil C is driven by the conveying device 100 to the outside of the post-processing device 400 and stored in a roll with the help of the reel 500, that is, oxygen-free copper. foil products.

The oxygen content of the oxygen-free copper foil product was characterized, and the characterization results showed that the oxygen content in the prepared product foil C was 2.8-3.0ppm, which met the standard of oxygen-free copper foil, and the oxygen content was extremely low;

In addition, samples were taken from the intermediate product of medium-foil B, and the copper foil was peeled off to characterize its oxygen content. The characterization results showed that its oxygen content was 2.6-2.9, which shows that in the subsequent post-treatment process, it did not increase significantly. oxygen content.

In addition, in this embodiment, the current density is controlled to be 3A/dm ² , the temperature of the electrolyte is 50°C, and the load time of the conductive medium A is controlled by the transmission device 100 from entering the electrolyte to when the electrolyte is discharged. The load time in this embodiment is 4 minutes , the thickness of the obtained product foil C is 3.0 μm, and its tensile strength is characterized, and the characterization results show that its tensile strength can reach 366 MPa, which has very excellent tensile properties.

It can be seen that the technical solution of the present invention can be directly, simply and effectively applied to the existing electrodeposition system, and the above-mentioned device coordination and system can be formed by improving it to a certain extent.

Claims (9)

1. A method for preparing zero-stress electrolytic metal foil is characterized in that,

the method comprises the following steps:

1) Arranging a movable conductive medium, wherein the conductive medium can dynamically pass through electrolyte, is electrically connected with an anode arranged in the electrolyte when in the electrolyte, and is used as a cathode to carry out electrodeposition preparation of metal foil on the conductive medium to obtain a conductive medium-metal foil;

2) And separating and removing the conductive medium component in the conductive medium-metal foil by a phase state change and/or chemical method and/or a dissolution and/or expansion and contraction method, namely completing the zero-stress preparation of the electrolytic metal foil.

2. The method of claim 1, wherein the step of preparing the electrolytic metal foil is further comprised of,

step 1), the movable conductive medium is put into the electrolyte in the form of a strip and/or a sheet of a target shape and/or a setting and curing slurry.

3. The method of claim 2, wherein the step of preparing the electrolytic metal foil is further comprised of,

and filling the sizing and curing slurry into a specific carrier, performing gravity leveling and/or shape pressing, and curing to obtain the conductive medium.

4. The method of claim 1, wherein the step of preparing the electrolytic metal foil is further comprised of,

step 1) the electrolyte contains soluble metal salt of a target metal foil component;

the anode in the step 1) is an insoluble anode.

5. A zero stress electrolytic metal foil system characterized in that,

the system is used for carrying out electrodeposition on a conductive medium and comprises a deposition device and a post-treatment device;

the deposition device comprises an electrolytic cell, a cathode, an anode and a power supply;

the cathode, the anode and the power supply are electrically connected;

the electrolytic cell is used for containing electrolyte, the anode is arranged in the electrolytic cell, the cathode is electrically connected with the conductive medium, and the conductive medium is used as an extension part of the cathode, so that the conductive medium exists as the cathode in the electrolytic cell for electrodeposition;

the post-treatment device is used for removing the conductive medium and comprises a solvent pool, a heating device, a refrigerating device, a combustion device, an atmosphere treatment device and a spraying device.

6. The zero-stress electrolytic metal foil system of claim 5,

the system further comprises a conveying device for enabling transport of the conductive medium.

7. The zero-stress electrolytic metal foil system of claim 6,

the system also comprises a pretreatment device;

the pretreatment device is used for loading a conductive medium on a carrier and/or performing surface treatment on the conductive medium;

the carrier moves under the drive of the conveying device, and the carrying conductive medium sequentially passes through the deposition device and the post-processing device.

8. The zero-stress electrolytic metal foil system of claim 7,

the pretreatment device comprises a spraying device and/or a brushing device and/or a solvent pool and/or a heating device and/or a refrigerating device and/or a UV curing device.

9. Use of the method according to claims 1 to 4,

the method is used for producing metal foils with the thickness dimension being more than or equal to 2 mu m, and/or is used for producing large-size metal foils with the length dimension specification being more than or equal to 3m and the width dimension specification being more than or equal to 1.2m, and/or is used for continuously producing metal foil rolls.

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