CN115287726A

CN115287726A - Preparation device and method of titanium roller oxide film, copper foil and preparation method of copper foil

Info

Publication number: CN115287726A
Application number: CN202211025369.9A
Authority: CN
Inventors: 盛银莹; 单大勇
Original assignee: Institute of Corrosion Science and Technology
Current assignee: Institute of Corrosion Science and Technology
Priority date: 2022-08-25
Filing date: 2022-08-25
Publication date: 2022-11-04
Anticipated expiration: 2042-08-25
Also published as: CN115287726B

Abstract

The invention discloses a device and a method for preparing a titanium roller oxide film, a copper foil and a preparation method thereof, and belongs to the technical field of copper foils. The device comprises a titanium plate, an oxidation tank and a titanium roller; the titanium roller and the titanium plate are arranged at intervals, and the titanium plate and at least partial area of the titanium roller in the circumferential direction are positioned in the oxidation tank; the oxidizing liquid contained in the oxidizing tank is immersed in a gap between the titanium roller and the titanium plate in the preparation process so as to enable the oxidizing liquid to form an oxide film on the surface of the titanium roller under the condition of electrification. The preparation device does not need to polish the titanium roller in the production process, and can supplement oxidation in due time to ensure the stable surface state, thereby greatly reducing the production and maintenance cost, avoiding the damage of arc points and the like, and prolonging the service life of the titanium roller. The copper foil is further prepared by the titanium roller with the oxide film, so that the speed of hydrogen absorption of a titanium material can be reduced, the corrosion of the titanium roller is slowed down, high-performance ultrathin and ultrathin copper foil can be effectively and stably prepared, and the percent of pass of the whole-roll copper foil is improved.

Description

Preparation device and method of titanium roller oxide film, copper foil and preparation method of copper foil

Technical Field

The invention relates to the technical field of copper foil, in particular to a device and a method for preparing a titanium roller oxide film, copper foil and a preparation method thereof.

Background

The electrolytic copper foil has excellent signal and power transmission capability and plays a significant role in the new energy electric vehicle industry and the 5G electronic information industry. In order to meet the increasing demand of power batteries for high specific energy density, the development of thinner, stronger and tougher copper foils is imperative. However, in the conventional copper foil production method, a roll continuous electrolysis method is adopted, and a cathode roll is a core device of the electrolytic copper foil, and the crystal grain size, the crystal structure, the surface state and the like of the cathode roll determine the initial crystallization state of the electrolytic copper foil, which greatly affects the quality of the electrolytic copper foil. The finer the crystal grains on the surface of the cathode roll, the finer the crystal grains of the electrolytic copper foil, and the more uniform the geometrical arrangement, the more easily the ultrathin and tough copper foil can be obtained. On the other hand, the copper foil is relatively thick due to coarse crystals.

Particularly, the initial deposition of the copper foil is greatly influenced by the surface state, the copper foil which is unwound in the production has more pinholes of about 100-200 meters, the performance is poor, and the copper foil needs to be discarded, so that the waste and the production cost are increased. This is because the oxide layer on the surface of the fresh titanium roller is unstable, which is not favorable for the adsorption of additives and thus affects the deposition of copper ions. After the copper foil is used for a period of time, the surface of the cathode roller is always in a changing state due to electrochemical corrosion and mechanical corrosion, the titanium roller is easy to absorb hydrogen to form titanium hydride to accelerate corrosion, the corrosion layer becomes thicker and thicker, the surface of the cathode roller becomes black and not bright, the roughness is increased, the internal stress of the copper foil is increased, the copper foil is rolled, the smooth surface of the copper foil is possibly provided with special brightness or stripes, the qualified rate of the copper foil production is greatly reduced, and the problems are more serious for producing the ultra-thin copper foil with the thickness of below 4.5 mu m.

In order to reduce the adverse effect caused by the change of the surface state of the cathode roller, in the current practical production, the cathode roller needs to be subjected to surface grinding and polishing after being used for a period of time, so that a corrosion layer on the surface is removed, an extremely thin new oxide film is generated on the surface, the metal activity of the surface of the cathode roller is ensured, the surface potential is more negative and is not easy to corrode, and the current is ensured to be uniformly distributed on the surface of the titanium roller. However, the mechanical polishing step of the cathode roll is difficult to be completely consistent, greatly affects the stability of the formula and the process, and greatly increases the production and maintenance cost. Off-line polishing and grinding needs a foil generating machine to stop production, and a cathode roller with the weight of 10t is dismounted, so that the method is unsafe and influences production; the online polishing is carried out on a normally-operated foil producing machine, but damages such as arc points and the like generated on the surface of the cathode roller are difficult to repair, but when a newly polished titanium roller is used for deposition production, the copper foil is inevitably wasted during uncoiling.

In view of the above, the present invention is particularly proposed.

Disclosure of Invention

An object of the present invention is to provide a device for preparing an oxide film of a titanium roller, which solves at least one of the above problems.

The second purpose of the invention is to provide a method for preparing the titanium roller oxide film by adopting the preparation device.

The invention also aims to provide a preparation method of the copper foil on the surface of the titanium roller.

The fourth object of the present invention is to provide a copper foil produced by the above production method.

The application can be realized as follows:

in a first aspect, the application provides a preparation device of a titanium roller oxidation film, which comprises a titanium plate, an oxidation tank and a titanium roller;

at least partial area of the titanium plate is positioned in the oxidation tank, the titanium roller and the titanium plate are arranged at intervals, and in the preparation process of the oxidation film, at least partial area of the circumferential direction of the titanium roller is positioned in the oxidation tank; the oxidizing liquid contained in the oxidizing tank is immersed in a gap between the titanium roller and the titanium plate in the preparation process so as to enable the oxidizing liquid to form an oxide film on the surface of the titanium roller under the condition of electrification.

In an optional embodiment, the oxidation tank is further provided with an oxidation liquid inlet and outlet, and the oxidation liquid inlet and outlet is used for being connected with an external oxidation liquid supply container.

In an optional embodiment, the oxidizing liquid inlet and outlet are further provided with a valve for controlling the inlet and outlet of the oxidizing liquid.

In an alternative embodiment, the preparation device further comprises a power supply, and the power supply is simultaneously connected with the titanium plate and the titanium roller.

In a second aspect, the present application provides a method for preparing a titanium roller oxide film, comprising the steps of: the production apparatus according to any one of the above embodiments is used, and the titanium roller is rotated under an energization condition with the titanium plate as the cathode and the titanium roller as the anode, so that the oxidizing solution in the oxidation tank forms a titanium oxide film on the surface of the titanium roller.

In an alternative embodiment, the speed of rotation of the titanium rollers is between 2 and 6m/min.

In an alternative embodiment, the voltage is controlled to be 20 to 50V during the preparation of the oxide film.

In an alternative embodiment, the oxidizing solution comprises at least 2 of oxalic acid, sulfuric acid, nitrilotriacetic acid, citric acid, and fatty acid methyl ester polyoxyethylene ether.

In an optional embodiment, the oxidizing solution at least comprises 10-20g/L of oxalic acid and 100-200g/L of sulfuric acid.

In an alternative embodiment, before depositing the titanium oxide film, the method further comprises polishing the titanium roller.

In an alternative embodiment, the roughness Ra of the titanium roller after polishing treatment is 0.2 to 0.4 μm.

In a third aspect, the application provides a method for preparing a copper foil on the surface of a titanium roller, which comprises the following steps: the titanium roll with the oxide film prepared in the previous embodiment is used as a cathode, a titanium plate in a preparation device for preparing the oxide film of the titanium roll is replaced by a titanium iridium tantalum coating anode plate, an electrolyte is introduced into an oxidation tank, and copper foil is deposited on the surface of the titanium roll with the oxide film under the electrolysis condition.

In an alternative embodiment, the method further comprises the step of stripping and rolling the titanium roller deposited with the copper foil.

In an optional embodiment, during the electrolysis, the current is 25000-35000A, the temperature is 48-55 ℃, and the rotation speed of the titanium roller is 5-10m/min.

In an alternative embodiment, the main components of the electrolyte comprise 350-360g/L of copper sulfate, 100-130g/L of sulfuric acid and 10-20mg/L of chlorine salt.

In alternative embodiments, the chloride salt is copper chloride or sodium chloride.

In an alternative embodiment, the electrolyte further comprises additives.

In an alternative embodiment, the additive includes at least one of a wetting agent, a brightener, a leveler, a high resistance agent, and a toughener.

In an alternative embodiment, the wetting agent comprises a polyether compound; and/or the brightening agent comprises at least one of sodium polydithio-dipropyl sulfonate, sodium 3-mercapto-1-propane sulfonate, sodium N, N-dimethyl-dithio-carbonyl propane sulfonate and thiazolidinethione; and/or, the leveling agent comprises an amine compound; and/or, the high resistance agent comprises ethylene thiourea; and/or the toughening agent comprises at least one of organic sulfide with sulfonic acid groups, quaternary amine compounds and amino urea modified polymers.

In an alternative embodiment, the wetting agent comprises at least one of hydroxyethylcellulose and polyethylene glycol; preferably, the molecular weight of the polyethylene glycol is 6000 to 8000.

In alternative embodiments, the leveling agent comprises at least one of a polypeptide protein, gelatin, bone glue, and alkylated polyethyleneimine.

In an alternative embodiment, the toughening agent includes at least one of an L fatty amine ethoxylate sulfonate, a quaternary amine compound, and an aminourea-based modified polymer.

In an alternative embodiment, the electrolyte contains at least one of 50-200mg/L hydroxyethyl cellulose and 10-100mg/L polyethylene glycol;

and/or the electrolyte contains at least one of 0-50mg/L of sodium polydithio-dipropyl sulfonate, 0-50mg/L of 3-mercapto-1-propane sulfonate, 0-10mg/L of sodium N, N-dimethyl-dithio-carbonyl propane sulfonate and 2-6mg/L of thiazolidinethione;

and/or the electrolyte contains at least one of 50-100mg/L polypeptide protein and 20-60mg/L alkylated polyethyleneimine;

and/or the electrolyte contains 0.2-0.5mg/L ethylene thiourea;

and/or the electrolyte contains 1-5mL/L of at least one of fatty amine ethoxy sulfonate, 2-10mL/L of quaternary amine compound and 5-10mL/L of amidourea modified polymer.

In an alternative embodiment, when the electrolyte contains polypeptide protein and at least one of 3-mercapto-1-propane sodium sulfonate and polydithio dipropyl sodium sulfonate, the dosage ratio of the 3-mercapto-1-propane sodium sulfonate and the polydithio dipropyl sodium sulfonate to the polypeptide protein is 0-1:1.

In an alternative embodiment, when the electrolyte contains both sodium polydithio-dipropyl sulfonate and sodium N, N-dimethyl-dithiocarbonyl propane sulfonate, the ratio of the amounts of sodium polydithio-dipropyl sulfonate and sodium N, N-dimethyl-dithiocarbonyl propane sulfonate is 5-8:1.

In a fourth aspect, the present application provides a copper foil prepared by the method of any one of the preceding embodiments.

In an alternative embodiment, the copper foil has a thickness of 4-6 μm.

The beneficial effect of this application includes:

the preparation device provided by the application does not need to grind and polish the titanium roller in the production process, and the surface state can be ensured to be stable by timely supplementing oxidation, so that the production and maintenance cost is greatly reduced, damages such as arc points and the like can be avoided, and the service life of the titanium roller is prolonged. The copper foil is further prepared by the titanium roller with the oxide film, so that the speed of hydrogen absorption of a titanium material can be reduced, the corrosion of the titanium roller is slowed down, high-performance ultrathin and ultrathin copper foil can be effectively and stably prepared, and the percent of pass of the whole-roll copper foil is improved. The prepared copper foil has no pinholes, no warping, excellent performance (such as normal-temperature tensile strength and elongation), fine microstructure and good flexibility.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

Fig. 1 is a schematic structural diagram of a preparation apparatus provided in the present application.

Icon: 1-a titanium plate; 2-an oxidation tank; 3-a titanium roller; 4-an oxidizing liquid supply container; 5-liquid inlet and outlet channels; 6-a valve; 7-electrolyte inlet.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.

The following specifically describes an apparatus and a method for producing a titanium roll oxide film, a copper foil, and a method for producing the same.

The application provides a preparation device of a titanium roller oxidation film, which comprises a titanium plate 1, an oxidation tank 2 and a titanium roller 3, as shown in figure 1.

At least partial area of the titanium plate 1 is positioned in the oxidation tank 2, the titanium roller 3 and the titanium plate 1 are arranged at intervals, and in the preparation process of the oxidation film, at least partial area of the titanium roller 3 in the circumferential direction is positioned in the oxidation tank 2; the oxidizing liquid contained in the oxidizing tank 2 is immersed in a gap between the titanium roller 3 and the titanium plate 1 in the preparation process, so that the oxidizing liquid forms an oxide film on the surface of the titanium roller 3 under the condition of electrification.

Preferably, in the preparation of the oxide film, a half area of the titanium roll 3 in the circumferential direction is located in the oxidation tank 2. The area of the titanium plate 1 in the oxidation tank 2 can correspond to the surface of the titanium roll 3 in the oxidation tank 2 so that the surface of the titanium roll in the oxidation tank 2 can be formed with an oxide film.

The oxidation tank 2 is also provided with an oxidation liquid inlet and outlet which are used for being connected with an external oxidation liquid supply container 4 through a liquid inlet and outlet channel 5.

Preferably, the oxidizing liquid inlet and outlet are also provided with a valve 6 for controlling the inlet and outlet of the oxidizing liquid, so that the oxidizing liquid in the oxidizing liquid supply container 4 is introduced into the oxidizing tank 2 when liquid needs to be fed; when the preparation of the oxidation film is finished, the oxidation liquid can be returned to the oxidation liquid supply container 4 through the valve 6; when the catalyst needs to be reused, the valve 6 is opened and then the catalyst is introduced into the oxidation tank 2 again, so that the catalyst can be recycled.

Further, the preparation device also comprises a power supply which is simultaneously connected with the titanium plate 1 and the titanium roller 3.

Correspondingly, the application also provides a preparation method of the titanium roller oxide film, which comprises the following steps: by adopting the preparation device, the titanium plate 1 is used as a cathode, the titanium roller 3 is used as an anode, and the titanium roller 3 is rotated under the electrified condition, so that the oxidizing solution in the oxidation tank 2 forms a titanium oxide film on the surface of the titanium roller 3.

Preferably, the titanium roller 3 may be subjected to polishing treatment before the titanium oxide film is deposited. The roughness Ra of the titanium roller 3 after polishing treatment is preferably controlled to be 0.2 to 0.4. Mu.m.

For reference, siC abrasive belts and scouring pads with different specifications can be adopted for polishing the titanium roller 3, and defects, oxidation layers and abrasive belt traces remained in the titanium roller 3 during processing are gradually removed. In addition, chemical polishing may be used instead of mechanical polishing to achieve the above roughness values. The chemical polishing liquid can be made of HF, HNO ₃ And lactic acid in a certain proportion.

In the above-mentioned rotating process, the rotating speed of the titanium roller 3 can be 2-6m/min, such as 2m/min, 2.5m/min, 3m/min, 3.5m/min, 4m/min, 4.5m/min, 5m/min, 5.5m/min or 6m/min, etc., and can also be any other value within the range of 2-6m/min. Rotating at the above rotation speed for 1-3 weeks to form uniform titanium oxide film.

It should be noted that in potentiostatic mode, the current varies during the oxidation phase, is high during the initial oxidation phase and then decreases rapidly to a minimum value, with a subsequent slow increase in current density due to the oxygen evolution reaction. The appropriate rotation speed can ensure that the oxide film with appropriate thickness and uniform composition and appearance is finally generated. If the rotation speed is too high, the formed oxide film is rough and the crystallization is uneven; if the rotating speed is too slow, oxygen evolution reaction is triggered, and the aging stage is entered.

In the process of preparing the oxide film, the voltage can be controlled to be 20-50V, such as 20V, 25V, 30V, 35V, 40V, 45V or 50V, and can be any other value within the range of 20-50V.

It should be noted that the growth and crystallization processes of the titanium anodized film differ depending on the applied potential. If the voltage is lower than 20V, the growth and crystallization of the oxide film will be slow. If the voltage is too high, the current density during oxidation is high, and the growth and dissolution of the oxide film are fast, resulting in high surface roughness of the oxide film.

For reference, the oxidizing solution used in the preparation process includes at least 2 of oxalic acid, sulfuric acid, nitrilotriacetic acid, citric acid, and fatty acid methyl ester polyoxyethylene ether.

Preferably, the oxidizing solution comprises at least 10-20g/L (e.g., 10g/L, 12g/L, 15g/L, 18g/L or 20g/L, etc.) oxalic acid and 100-200g/L (e.g., 100g/L, 120g/L, 150g/L, 180g/L or 200g/L, etc.) sulfuric acid.

By the above method, an oxide film having a thickness of not more than 100 μm can be formed on the surface of the titanium roller, the oxide film being mainly composed of titanium oxide. The formed oxide film was visually observed to be uniform blue, dark cyan, and golden yellow.

In addition, the application also provides a preparation method of the copper foil on the surface of the titanium roller, which comprises the following steps: the titanium roll with the oxide film prepared above is used as a cathode, the titanium plate 1 in the preparation device for preparing the oxide film of the titanium roll is replaced by a titanium iridium tantalum coating anode plate, an electrolyte is introduced into an oxidation tank 2, and copper foil is deposited on the surface of the titanium roll with the oxide film under the electrolysis condition.

Preferably, in the above-mentioned apparatus for preparing titanium roller oxide film, the bottom of the oxidation tank 2 may further be provided with an electrolyte inlet 7 for introducing electrolyte according to the requirement.

And (4) after the electrolytic deposition is finished, peeling and rolling the titanium roller deposited with the copper foil.

For reference, in the above electrolysis process, the current may be 25000-35000A, the temperature is 48-55 deg.C, and the rotation speed of the titanium roller is 5-10m/min.

The current may be 25000A, 26000A, 27000A, 28000A, 29000A, 30000A, 31000A, 32000A, 33000A, 34000A, 35000A, or the like, or may have any other value within a range of 25000 to 35000A.

It is emphasized that current density is a core parameter of deposited copper foil, which, in addition to determining production efficiency, mainly affects grain nucleation and growth. If the current is lower than 25000A, the production efficiency is low, and the crystal grains are coarse; if the current is higher than 35000A, the edge of the copper foil is easily burnt, and more importantly, the current density is too high, which causes the oxide film to be dissolved too fast.

The temperature may be 48 ℃, 49 ℃, 50 ℃, 51 ℃, 52 ℃, 53 ℃, 54 ℃ or 55 ℃ or any other value within the range of 48-55 ℃.

It should be noted that if the temperature is too low, the current density will be low; if the temperature is too high, the additive (such as protein) is easily decomposed and loses efficacy.

The rotation speed can be 5m/min, 5.5m/min, 6m/min, 6.5m/min, 7m/min, 7.5m/min, 8m/min, 8.5m/min, 9m/min, 9.5m/min, 10m/min or the like, and can also be any other value within the range of 5-10m/min.

By controlling the rotation speed within the above range, the deposition rate can be controlled within a more appropriate range in combination with the above current conditions.

The electrolyte mainly comprises 350-360g/L (such as 350g/L, 352g/L, 355g/L, 358g/L or 360 g/L) of copper sulfate, 100-130g/L (such as 100g/L, 105g/L, 110g/L, 115g/L, 120g/L, 125g/L or 130 g/L) of sulfuric acid and 10-20mg/L (such as 10mg/L, 12mg/L, 15mg/L, 18mg/L or 20 mg/L) of chloride salt.

Wherein the chloride salt can be sodium chloride after copper chloride.

Further, the electrolyte may further include additives, such as at least one of a wetting agent, a brightening agent, a leveling agent, a high-resistance agent, and a toughening agent.

Wherein the wetting agent may comprise polyether compound, such as at least one of hydroxyethyl cellulose (HEC) and polyethylene glycol (PEG, molecular weight of 6000-8000).

The brightening agent may include at least one of sodium polydithio dipropyl sulfonate (SPS), sodium 3-mercapto-1-propane sulfonate (MPS), sodium N, N-dimethyl-dithio carbonyl propane sulfonate (DPS), and thiazolidinethione (H1). The brightener can play a role in increasing cathode polarization, refining grains and improving the brightness of the rough surface of the copper foil.

The leveler may include an amine compound, and may include at least one of polypeptide protein (QS), gelatin, bone glue, and alkylated polyethyleneimine, for example.

The high resistance agent may include ethylene thiourea. By adding a high resistance agent to the electrolyte, a copper foil with high tensile strength can be obtained.

The toughening agent can comprise at least one of organic sulfide with sulfonic acid groups, quaternary ammonium compounds and amidourea modified polymers, and can comprise at least one of L fatty amine ethoxy sulfonate, quaternary ammonium compounds and amidourea modified polymers. The copper foil with high elongation can be obtained by adding the toughening agent into the electrolyte.

In some embodiments, the electrolyte solution can include 50-200mg/L (e.g., 50mg/L, 80mg/L, 100mg/L, 120mg/L, 150mg/L, 180mg/L, or 200mg/L, etc.) of hydroxyethyl cellulose and 10-100mg/L (e.g., 10mg/L, 20mg/L, 30mg/L, 40mg/L, 50mg/L, 60mg/L, 70mg/L, 80mg/L, 90mg/L, or 100mg/L, etc.) of polyethylene glycol.

In some embodiments, the electrolyte solution may contain at least one of 0 to 50mg/L (e.g., 0mg/L, 10mg/L, 20mg/L, 30mg/L, 40mg/L, or 50mg/L, etc.) of sodium polydithio dipropyl sulfonate, 0 to 50mg/L (e.g., 0mg/L, 10mg/L, 20mg/L, 30mg/L, 40mg/L, or 50mg/L, etc.) of sodium 3-mercapto-1-propane sulfonate, 0 to 10mg/L (e.g., 0mg/L, 2mg/L, 4mg/L, 6mg/L, 8mg/L, or 10mg/L, etc.) of sodium N, N-dimethyl-dithio-carbonyl propane sulfonate, and 2 to 6mg/L of thiazolidinethione.

In some embodiments, the electrolyte can contain 50-100mg/L (e.g., 50mg/L, 60mg/L, 70mg/L, 80mg/L, 90mg/L, 100mg/L, etc.) of the polypeptide protein and 20-60mg/L (e.g., 20mg/L, 25mg/L, 30mg/L, 35mg/L, 40mg/L, 45mg/L, 50mg/L, 55mg/L, or 60mg/L, etc.) of at least one of an alkylated polyethyleneimine.

In some embodiments, the electrolyte solution may contain 0.2-0.5mg/L (e.g., 0.2mg/L, 0.25mg/L, 0.3mg/L, 0.35mg/L, 0.4mg/L, 0.45mg/L, or 0.5mg/L, etc.) of ethylene thiourea.

In some embodiments, the electrolyte can contain 1-5mL/L (e.g., 1mL/L, 1.5mL/L, 2mL/L, 2.5mL/L, 3mL/L, 3.5mL/L, 4mL/L, 4.5mL/L, or 5mL/L, etc.) of the aliphatic amine ethoxylate sulfonate, 2-10mL/L (e.g., 2mL/L, 3mL/L, 4mL/L, 5mL/L, 6mL/L, 7mL/L, 8mL/L, 9mL/L, or 10mL/L, etc.) of the quaternary amine compound, and 5-10mL/L (e.g., 5mL/L, 6mL/L, 7mL/L, 8mL/L, 9mL/L, or 10mL/L, etc.) of the aminourea-based modifying polymer.

Preferably, when the electrolyte contains polypeptide protein and at least one of sodium 3-mercapto-1-propane sulfonate and sodium polydithio-dipropyl sulfonate, the dosage ratio of the sodium 3-mercapto-1-propane sulfonate and the sodium polydithio-dipropyl sulfonate to the polypeptide protein is 0-1:1, such as 0:1, 0.2.

When the electrolyte contains sodium polydithio-dipropyl sulfonate and sodium N, N-dimethyl-dithio-carbonyl propane sulfonate, the dosage ratio of the sodium polydithio-dipropyl sulfonate to the sodium N, N-dimethyl-dithio-carbonyl propane sulfonate can be 5-8:1, such as 5:1, 6:1, 7:1 or 8:1.

Accordingly, the present application provides a copper foil prepared by the above-described preparation method.

Preferably, the prepared copper foil has the thickness of 4-6 μm, no pinholes or warping, excellent performance, fine microstructure and good flexibility. The tensile strength at normal temperature reaches 480-680MPa, and the elongation reaches 5-15%.

The features and properties of the present invention are described in further detail below with reference to examples.

Example 1

The embodiment provides a titanium roller oxide film, which is prepared by adopting the following method and device:

the device comprises a titanium plate 1, an oxidation tank 2, a titanium roller 3 and a power supply.

The half area of the circumferential direction of the titanium roller 3 is positioned in the oxidation tank 2, the titanium plate 1 is completely positioned in the oxidation tank 2, the titanium roller 3 and the titanium plate 1 are arranged at intervals, and the area of the titanium plate 1 positioned in the oxidation tank 2 corresponds to the surface of the titanium roller 3 positioned in the oxidation tank 2. The bottom of the oxidation tank 2 is provided with an oxidation liquid inlet and outlet which are used for being connected with an external oxidation liquid supply container 4. And a valve 6 for controlling the inlet and outlet of the oxidizing liquid is arranged at the inlet and outlet of the oxidizing liquid. The power supply is connected with the titanium plate 1 and the titanium roller 3 simultaneously.

The method comprises the following steps:

(1) Polishing and grinding the titanium cathode roller: siC abrasive belts and scouring pads with different specifications are adopted for grinding and polishing the titanium cathode roller, the defects, the oxidation layer and the abrasive belt traces remained in the titanium roller are gradually removed, and finally the Ra value of the roughness reaches 0.2 mu m;

(2) Anodic oxidation treatment of the cathode titanium roller: and in the preparation process of the oxide film, the oxidizing liquid contained in the oxidation tank 2 is immersed in the gap between the titanium roller 3 and the titanium plate 1 in the preparation process.

Turning on an oxidation power supply, setting the voltage to be 35V, setting the rotation speed of the titanium roller to be 4m/min, rotating at a constant speed for 2 weeks to form a layer of uniform titanium oxide film, and turning off the power supply.

The oxidizing solution was composed of 10g/L oxalic acid, 200g/L sulfuric acid (98 wt%), and 30g/L nitrilotriacetic acid.

(3) After oxidation, the oxidizing liquid in the oxidation tank 2 is discharged and stored in an oxidizing liquid supply container 4 which is specially used for storing the oxidizing liquid, and when the oxidizing liquid is used again, the oxidizing liquid is introduced into the oxidation tank 2 through a liquid inlet pipe and a valve 6.

The thickness of the oxide film formed on the surface of the titanium roller 3 was 20 μm.

Example 2

This example provides a copper foil, which is prepared as follows:

(1) By using the apparatus of example 1, the cathode titanium plate 1 for oxidation was replaced with a titanium iridium tantalum coated anode plate, and the electrolytic solution was introduced from the bottom of the oxidation tank 2 by using a titanium roll having an oxide film as a cathode roll.

Wherein the electrolyte comprises a main component and an additive. The main components of the electrolyte per L comprise 355g/L copper sulfate, 115g/L sulfuric acid and 15mg/L copper chloride. The additive comprises 100mg/L of hydroxyethyl cellulose, 50mg/L of sodium polydithio-dipropyl sulfonate, 10mg/L of sodium N, N-dimethyl-dithio-carbonyl propane sulfonate, 50mg/L of polypeptide protein, 0.35mg/L of ethylene thiourea and 7.5mL/L of aminourea modified polymer.

That is, the ratio of the amount of sodium polydithio-dipropyl sulfonate to the amount of polypeptide protein is 1:1, and the ratio of the amount of sodium polydithio-dipropyl sulfonate to the amount of sodium N, N-dimethyl-dithiocarbonyl propane sulfonate is 5:1.

(2) And turning on a power supply to electrodeposit the copper foil, wherein the current is 30000A, the temperature of the electrolyte is controlled to be 50 ℃, and the rotating speed of the cathode roller is 7.5m/min.

(3) And peeling and rolling to obtain the copper foil with the thickness of 5 mu m.

Example 3

This example provides an oxide film which differs from example 2 only in that: in the preparation process of the oxide film, the rotating speed of the titanium roller is 2m/min.

Example 4

This example provides an oxide film which differs from example 2 only in that: in the preparation process of the oxide film, the rotation speed of the titanium roller is 6m/min.

Example 5

This example provides an oxide film which differs from example 2 only in that: in the preparation process of the oxide film, the voltage is 20V.

Example 6

This example provides an oxide film which differs from example 2 only in that: in the preparation process of the oxide film, the voltage is 50V.

Comparative example 1

This comparative example differs from example 2 in that: in the preparation process of the oxide film, the rotating speed of the titanium roller is 1m/min.

Comparative example 2

This comparative example differs from example 2 in that: in the preparation process of the oxide film, the rotating speed of the titanium roller is 8m/min.

Comparative example 3

This comparative example differs from example 2 in that: in the preparation process of the oxide film, the voltage is 10V.

Comparative example 4

This comparative example differs from example 2 in that: in the preparation process of the oxide film, the voltage is 60V.

Comparative example 5

This comparative example differs from example 2 in that: the main components of the electrolyte are 355g/L of copper sulfate, 115g/L of sulfuric acid and 15mg/L of copper chloride. The additive comprises 100mg/L of hydroxyethyl cellulose, 100mg/L of sodium polydithio-dipropyl sulfonate, 10mg/L of sodium N, N-dimethyl-dithio-carbonyl propane sulfonate, 50mg/L of polypeptide protein, 0.35mg/L of ethylene thiourea and 7.5mL/L of aminourea modified polymer.

That is, the dosage ratio of the sodium polydithio-dipropyl sulfonate to the polypeptide protein is 2:1.

Comparative example 6

The comparative example differs from example 2 in that: the main components of the electrolyte per L comprise 355g/L copper sulfate, 115g/L sulfuric acid and 15mg/L copper chloride. The additive comprises 100mg/L hydroxyethyl cellulose, 50mg/L sodium polydithio-dipropyl sulfonate, 5mg/L sodium N, N-dimethyl-dithio-carbonyl propane sulfonate, 50mg/L polypeptide protein, 0.35mg/L ethylene thiourea and 7.5mL/L aminourea modified polymer.

That is, the amount ratio of sodium polydithio-dipropyl sulfonate to sodium N, N-dimethyl-dithiocarbonyl propane sulfonate was 10.

Comparative example 7

This comparative example differs from example 2 in that:

the main components of the electrolyte per L comprise 360g/L copper sulfate, 130g/L sulfuric acid and 20mg/L copper chloride. The additive comprises 50mg/L polyethylene glycol (molecular weight is 7000), 50 mg/L3-mercapto-1-propane sodium sulfonate, 50mg/L polypeptide protein, 40mg/L alkylated polyethyleneimine, 0.5mg/L ethylene thiourea and 5mL/L fatty amine ethoxy sulfonate.

I.e. the additive contains only part of the ingredients.

Test examples

(1) And, when examples 2 to 6 are taken as examples, the results show that: the copper foils prepared in examples 2 to 6 all had no pinholes, no curling, and fine microstructures.

(2) According to the part 1 of GB/T228.1-201 metal material tensile test: the copper foils obtained in examples 2 to 6 and comparative examples 1 to 7 were subjected to performance tests in accordance with the room temperature test method and the copper foil test method for printed boards GB/T29847 to 2013, and the results are shown in Table 1.

TABLE 1 test results

As can be seen from table 1:

A. it can be seen from the comparison of example 2 and comparative examples 1-2 that when the rotation speed of the titanium roller is too low or too high during the preparation of the oxide film, the mechanical properties of the copper foil are reduced.

B. It can be seen from the comparison of example 2 and comparative examples 3 to 4 that when the voltage is too low or too high during the preparation of the oxide film, the mechanical properties of the copper foil are also reduced.

C. It can be seen by comparing example 2 with comparative examples 5 and 6 that when the ratio of MPS/SPS and QS is outside the range of 0 to 1:1 (comparative example 5), or when the ratio of SPS and DPS is outside the range of 5 to 8:1 (comparative example 6), it corresponds to the obtained copper foil being inferior to example 2 in tensile strength, yield strength and elongation, indicating that the difference in the compounding ratio among the components has a significant effect on the tensile strength, yield strength and elongation of the copper foil even under the same electrolyte composition conditions.

D. It can be seen from the comparison of example 2 and comparative example 7 that the tensile strength, yield strength and elongation of the obtained copper foil are significantly reduced after the types of the additives are changed.

Therefore, in the preparation process of the oxide film, the tensile strength and the yield strength elongation of the copper foil can be effectively improved by proper rotating speed and voltage and proper additive components and proportion in the electrolysis process.

In summary, according to the electrolytic copper foil prepared by the titanium roller with the oxidized surface, the stable oxide film can reduce the adverse effect of the surface state of the titanium roller on the copper foil deposition, so that the initial deposition is uniform, and the percent of pass of the whole roll of copper foil is improved. When the surface of the titanium roller is provided with the oxide film, the flatness of the copper foil is greatly improved, and the method has absolute advantages for producing ultrathin or even extremely thin copper foil. In addition, the oxide film can reduce the speed of hydrogen absorption of the titanium material and slow down corrosion of the titanium roller. Before the titanium roller is used, the titanium roller is ground and polished to Ra0.4 off line, the titanium roller does not need to be ground and polished in the production process, and the surface state can be ensured to be stable by timely supplementing oxidation, so that the service life of the titanium roller is prolonged. The copper foil deposited on the oxide film has the advantages of no pinholes and low warpage, and the high-strength high-toughness ultrathin copper foil can be obtained by combining the additive process formula. According to the microstructure characterization, the matte surface crystal cell of the copper foil is fine and smooth, the structure is uniform, and the polished surface has no obvious grinding and polishing scratches. The method solves the technical bottleneck problem that the copper foil thickness is limited due to the influence of the surface state difference of the titanium roller on the copper foil quality in the prior art.

The above is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes will occur to those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The device for preparing the titanium roller oxide film is characterized by comprising a titanium plate, an oxidation tank and a titanium roller;

at least partial area of the titanium plate is positioned in the oxidation tank, the titanium roller and the titanium plate are arranged at intervals, and in the preparation process of an oxidation film, at least partial area of the titanium roller in the circumferential direction is positioned in the oxidation tank; and the oxidizing liquid contained in the oxidizing tank is immersed in a gap between the titanium roller and the titanium plate in the preparation process so as to form an oxide film on the surface of the titanium roller by the oxidizing liquid under the condition of electrification.

2. The preparation device according to claim 1, wherein the oxidation tank is further provided with an oxidation liquid inlet and outlet, and the oxidation liquid inlet and outlet are used for being connected with an external oxidation liquid supply container;

preferably, the oxidizing liquid inlet and outlet are further provided with a valve for controlling the oxidizing liquid to enter and exit.

3. A production apparatus according to claim 1 or 2, further comprising a power supply connected to both the titanium plate and the titanium roller.

4. The preparation method of the titanium roller oxide film is characterized by comprising the following steps: the preparation device of any one of claims 1 to 3 is adopted, the titanium plate is used as a cathode, the titanium roller is used as an anode, and the titanium roller is rotated under the condition of electrification, so that the oxidizing solution in the oxidation tank forms a titanium oxide film on the surface of the titanium roller;

preferably, the rotating speed of the titanium roller is 2-6m/min;

preferably, in the preparation process of the oxide film, the voltage is controlled to be 20-50V;

preferably, the oxidizing solution comprises at least 2 of oxalic acid, sulfuric acid, nitrilotriacetic acid, citric acid, and fatty acid methyl ester polyoxyethylene ether;

preferably, the oxidizing solution at least comprises 10-20g/L of oxalic acid and 100-200g/L of sulfuric acid;

preferably, before the titanium oxide film is deposited, the titanium roller is polished;

preferably, the roughness Ra of the titanium roller after polishing treatment is 0.2-0.4 μm.

5. The preparation method of the copper foil on the surface of the titanium roller is characterized by comprising the following steps: adopting the titanium roller with the oxide film prepared by the preparation method of claim 4 as a cathode, replacing a titanium plate in a preparation device for preparing the oxide film of the titanium roller with a titanium iridium tantalum coating anode plate, introducing an electrolyte into an oxidation tank, and depositing a copper foil on the surface of the titanium roller with the oxide film under electrolysis conditions;

preferably, the method further comprises the step of peeling and rolling the titanium roller deposited with the copper foil.

6. The process according to claim 5, wherein the current is 25000 to 35000A, the temperature is 48 to 55 ℃ and the rotation speed of the titanium roll is 5 to 10m/min during the electrolysis.

7. The production method according to claim 5, wherein the main components of the electrolytic solution include 350 to 360g/L of copper sulfate, 100 to 130g/L of sulfuric acid, and 10 to 20mg/L of chlorine salt;

preferably, the chloride salt is copper chloride or sodium chloride.

8. The method according to claim 7, wherein the electrolyte further comprises additives;

preferably, the additive includes at least one of a wetting agent, a brightener, a leveler, a high resistance agent, and a toughener;

preferably, the wetting agent comprises a polyether compound; and/or the brightening agent comprises at least one of sodium polydithio-dipropyl sulfonate, sodium 3-mercapto-1-propane sulfonate, sodium N, N-dimethyl-dithio-carbonyl propane sulfonate and thiazolidinethione; and/or, the leveling agent comprises an amine compound; and/or, the high-resistance agent comprises ethylene thiourea; and/or the toughening agent comprises at least one of organic sulfide with sulfonic acid groups, quaternary amine compounds and amino urea modified polymers;

preferably, the wetting agent comprises at least one of hydroxyethyl cellulose and polyethylene glycol; more preferably, the molecular weight of the polyethylene glycol is 6000 to 8000;

preferably, the leveling agent comprises at least one of polypeptide protein, gelatin, bone glue, and alkylated polyethyleneimine;

preferably, the toughening agent comprises at least one of L fatty amine ethoxy sulfonate, quaternary amine compound and amino urea modified polymer.

9. The method according to claim 8, wherein the electrolyte contains at least one of 50 to 200mg/L of hydroxyethyl cellulose and 10 to 100mg/L of polyethylene glycol;

and/or the electrolyte contains at least one of 0-50mg/L sodium polydithio-dipropyl sulfonate, 0-50mg/L sodium 3-mercapto-1-propane sulfonate, 0-10mg/L sodium N, N-dimethyl-dithio-carbonyl propane sulfonate and 2-6mg/L thiazolidine thione;

and/or the electrolyte contains 0.2-0.5mg/L ethylene thiourea;

and/or the electrolyte contains 1-5mL/L of at least one of fatty amine ethoxy sulfonate, 2-10mL/L of quaternary amine compound and 5-10mL/L of aminourea modified polymer;

preferably, when the electrolyte contains polypeptide protein and at least one of 3-mercapto-1-propane sodium sulfonate and polydithio-dipropyl sodium sulfonate, the dosage ratio of the 3-mercapto-1-propane sodium sulfonate to the polydithio-dipropyl sodium sulfonate to the polypeptide protein is 0-1:1;

preferably, when the electrolyte contains sodium polydithio-dipropyl sulfonate and N, N-dimethyl-dithio-carbonyl propane sulfonate, the dosage ratio of the sodium polydithio-dipropyl sulfonate to the sodium N, N-dimethyl-dithio-carbonyl propane sulfonate is 5-8:1.

10. A copper foil produced by the production method according to any one of claims 5 to 9;

preferably, the copper foil has a thickness of 4 to 6 μm.