Acidic copper plating additive for thickening composite copper foil as well as preparation method and application of acidic copper plating additive

Abstract

The invention discloses an acidic copper plating additive for thickening a composite copper foil, and a preparation method and application thereof, and relates to the field of composite copper foil processing. The acidic copper plating additive is a single-component system and contains polyether, concentrated sulfuric acid and deionized water, the polyether is one or a mixture of two of a traditional inhibitor polyether compound and polyether sulfonate, and the polyether can contain 5-20% of modified polyether. The acidic copper plating additive of a single-component system can improve the stability of a plating solution and the crystallization consistency of a plating layer, CVS detection is not needed, the cost is reduced, modified polyether further refines plating layer grains, the flatness is improved, and the acidic copper plating additive is suitable for production of composite copper foil in the fields of new energy batteries and electronic circuits.

Description

Technical Field

[0001] This invention relates to the field of composite copper foil processing technology, specifically to acidic copper plating additives for thickening composite copper foil, their preparation methods, and applications. Background Technology

[0002] Composite copper foil is a key basic material in fields such as new energy batteries and electronic circuits. The copper plating thickening process directly affects the conductivity, structural stability, and service life of the product. Currently, the industry generally uses insoluble anodic acidic copper plating technology to thicken the copper plating of composite copper foil. This technology has become the mainstream process choice due to its advantages such as high current efficiency, fast thickening speed, and good coating uniformity.

[0003] In the acidic copper plating process, copper plating additives are the core element to ensure the quality of the coating. At present, most acidic copper plating additives are composed of three organic components: brightener, polyether, and leveling agent. The three components need to work together to ensure that the appearance and core performance of the composite copper foil coating meet the standards.

[0004] However, existing acidic copper plating additives and supporting processes have significant shortcomings: 1. The acidic plating solution itself is highly acidic, and the insoluble anode undergoes a strong oxygen evolution reaction during electroplating, resulting in the plating solution having extremely strong oxidizing power for organic matter. The three components of organic matter in acidic copper plating decompose at different rates in the copper plating bath, leading to large variations in the additive ratio and poor stability of the plating solution; 2. To maintain the stable concentration of the three-component additive, it is necessary to frequently use CVS to quantitatively analyze the three components separately. This detection method has high equipment investment costs and complex operation procedures.

[0005] Therefore, in order to solve the above problems, this invention proposes an acidic copper plating additive for thickening composite copper foil, its preparation method and application. Summary of the Invention

[0006] The purpose of this invention is to provide an acidic copper plating additive for thickening composite copper foil, its preparation method, and its application, so as to solve the problems raised in the prior art.

[0007] To achieve the above objectives, the present invention provides the following technical solution: An acidic copper plating additive for thickening composite copper foil comprises the following components: 5-100 g / L polyether, 1-20 mL / L concentrated sulfuric acid, and the balance being deionized water; the polyether is one or a mixture of two traditional inhibitor polyether compounds and polyether sulfonates.

[0008] Furthermore, the traditional inhibitor polyether compound is one or a mixture of polyethylene glycol, polypropylene glycol, and polyoxyethylene polyoxypropylene ether.

[0009] Furthermore, the polyether sulfonate is one or a mixture of polyoxypropylene ether sulfonate, polyoxyethylene ether sulfonate, sodium polyetherimide sulfonate, and sodium polyetherimide sulfonate derivatives.

[0010] In the above technical solution, traditional inhibitor polyether compounds are used as grain refiners, polyether sulfonates have a weak brightening effect, and concentrated sulfuric acid is used for sterilization.

[0011] Furthermore, the polyether also contains modified polyether, which is prepared by the following process: (1) In a nitrogen atmosphere, add the initiator and catalyst to the reactor, heat to 110-130℃, evacuate to a pressure of 0.5-1MPa, maintain for 30-60min, add ethylene oxide and 1,2-epoxybutane to the reactor, react for 8-10h to obtain the intermediate product; (2) Add cation exchange resin and dimethylformamide to the flask, and add the intermediate product obtained in step (1) and sodium 5-sulfonic acid isophthalate. Place the flask in a water bath at 60-70°C and heat and stir for 8-10 hours. Graft sodium 5-sulfonic acid isophthalate onto the intermediate product through esterification to obtain modified polyether.

[0012] Furthermore, in step (1), the initiator is one or a mixture of n-butanol, methanol, ethanol, propanol, cyclohexanol, and cyclopentanol; the catalyst is tris(pentafluorophenyl)borane. The molar ratio of initiator, catalyst, ethylene oxide and 1,2-epoxybutane is (0.1-0.5):(0.02-0.06):(1-2):1.

[0013] Furthermore, in step (2), the type of cation exchange resin is 001×7Na(732); The molar ratio of ethylene oxide, 1,2-epoxybutane, cation exchange resin and sodium isophthalate 5-sulfonic acid is (10-30):(5-15):(0.02-0.06):1.

[0014] Furthermore, the amount of modified polyether added is 5-20% of the total mass of the polyether.

[0015] The preparation method of acidic copper plating additive for thickening composite copper foil includes the following steps: Step 1: Add an appropriate amount of deionized water to a beaker, slowly add a certain amount of concentrated sulfuric acid to the water, stir and cool to room temperature; Step 2: Add a certain amount of polyether, stir until dissolved, and then dilute to the final volume with deionized water to obtain the acidic copper plating additive.

[0016] The application of acidic copper plating additives for thickening composite copper foil includes the following steps: S1: Preparation of base film: Take PP film or PET film as base film, and treat it with PVD (physical vapor deposition) to form a copper conductive layer on the surface of the base film; S2: Prepare copper plating solution: First, add deionized water to the copper plating tank, then slowly add concentrated sulfuric acid while stirring. After cooling to below 40°C, slowly add copper oxide powder while stirring, add deionized water to the calibration value, and after cooling to below 30°C, add 36% hydrochloric acid and acidic copper plating additive to obtain copper plating solution. S3: Electroplating: Immerse the base film obtained in S1 into the copper plating solution at a current density of 0.3-8 ASD and electroplat for 1-5 minutes to form a thickened copper layer; S4: Passivation and Drying: After passivation, the base film obtained in S3 is dried at 100-120℃ to obtain composite copper foil.

[0017] Furthermore, in step S2, the copper plating solution includes the following components: 50-150 mL / L concentrated sulfuric acid, 25-100 g / L copper oxide, 40-100 mg / L chloride ions, and 2-15 mL / L acidic copper plating additive; the chloride ions are sourced from 36% hydrochloric acid.

[0018] Furthermore, in step S4, the passivation process conditions are: at room temperature, immerse in chromic acid for 10-30 seconds for passivation.

[0019] Compared with the prior art, the beneficial effects of the present invention are: 1. The present invention describes an acidic copper plating additive for thickening composite copper foil, its preparation method, and its application. The present invention uses a single-component polyether additive, which avoids the imbalance caused by different decomposition rates in traditional three-component systems. The high molecular weight polyether has good antioxidant properties in insoluble anodic copper plating systems, which can greatly reduce the organic content in the plating solution, which is beneficial to maintaining the stability of the plating solution, reducing organic inclusions in the copper foil coating, and improving the quality and stability of the copper foil layer.

[0020] 2. The acidic copper plating additive for thickening composite copper foil described in this invention, its preparation method and application: This invention uses a single-component polyether additive to achieve good crystallization consistency and stable quality of the plating layer in the high, medium and low current density regions of the plating solution.

[0021] 3. The acidic copper plating additive for thickening composite copper foil described in this invention, its preparation method, and its application do not require CVS to detect components. Instead, a surface tension drop gravimeter is used to analyze a single component. The operation is simple, the equipment cost is low, the detection time and reagent consumption are reduced, and the total production cost is lowered.

[0022] 4. The acidic copper plating additive for thickening composite copper foil described in this invention, its preparation method, and its application: The modified polyether in this invention contains ester bonds and sulfonic acid groups, and contains a large number of electron-rich oxygen atoms, which can tightly and uniformly encapsulate copper ions, effectively inhibiting the excessively rapid precipitation of copper ions and enhancing the cathodic polarization effect; the cyclic structure of the modified polyether can fill the micro-pits of the plating layer, inhibit abnormal deposition in high current areas, reduce pitting and pinholes from the source, and also enhance the internal bonding force of the plating layer and reduce organic inclusions; the ester bonds and cyclic structure of the modified polyether can enhance its antioxidant properties in strongly acidic and high oxygen evolution environments, and reduce decomposition. Detailed Implementation

[0023] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] In the following specific implementation: 98% concentrated sulfuric acid should be used. The copper oxide powder has a particle size of 20-200 nm and a purity of ≥99%. The chloride ions are derived from 36% hydrochloric acid; The CAS number for polyethylene glycol is 25322-68-3, and its average molecular weight is 6000. The CAS number for polypropylene glycol is 25322-69-4; the CAS number for polyoxyethylene polyoxypropylene ether is 9003-11-6. Polyoxyethylene ether sulfonate was purchased from Hubei Xinghengye Technology Co., Ltd. The PP film and PET film were purchased from Anhui Tongfeng Electronics Co., Ltd. The CAS number for n-butanol is 71-36-3; The CAS number for methanol is 67-56-1; The CAS number for tri(pentafluorophenyl)borane is 1109-15-5; The CAS number for ethylene oxide is 75-21-8; The CAS number for 1,2-epoxybutane is 106-88-7; The cation exchange resin is designated as 001×7Na(732). The CAS number for dimethylformamide is 68-12-2; The CAS number for sodium isophthalate 5-sulfonate is 6362-79-4; Agents 6050A, 6050B, and 6050MU were purchased from Shenzhen Jiechengfa Technology Co., Ltd. The CAS number for KOH is 1310-58-3; The CAS number for sodium isophthalate is 6362-79-4; The CAS number for silane-modified polyether is 9038-95-3.

[0025] Example 1: A method for preparing an acidic copper plating additive for thickening composite copper foil, comprising the following steps: Step 1: Add deionized water to a beaker, slowly add concentrated sulfuric acid to the water, stir and cool to room temperature; Step 2: Add polyether, stir until dissolved, and then dilute to the final volume with deionized water to obtain the acidic copper plating additive; the acidic copper plating additive includes the following components: 50 g / L polyether, 5 mL / L concentrated sulfuric acid, and the balance is deionized water; the polyether is a mixture of polyethylene glycol and polyoxyethylene ether sulfonate, and the mass ratio of polyethylene glycol to polyoxyethylene ether sulfonate is 5:1; The application of acidic copper plating additives for thickening composite copper foil includes the following steps: S1: Preparation of base film: PP film is used as base film, and copper conductive layer is formed on the surface of the base film after PVD treatment; S2: Preparation of copper plating solution: First, add deionized water to the copper plating tank, then slowly add concentrated sulfuric acid while stirring. After cooling to 40℃, slowly add copper oxide powder while stirring, and replenish deionized water to the calibration value. After cooling to 30℃, add 36% hydrochloric acid and acidic copper plating additive to obtain the copper plating solution. The copper plating solution includes the following components: 120mL / L concentrated sulfuric acid, 30g / L copper oxide, 60mg / L chloride ions and 3mL / L acidic copper plating additive; the concentrated sulfuric acid is 98% concentrated sulfuric acid, the copper oxide powder has a particle size of 100nm and a purity of 99%, and the chloride ions are sourced from 36% hydrochloric acid. S3: Electroplating: Immerse the base film obtained in S1 into the copper plating solution at a current density of 2ASD and electroplat for 150s to form a thickened copper layer. S4: Passivation and Drying: After passivation, the film obtained in S3 is dried at 100°C to obtain composite copper foil.

[0026] Example 2: A method for preparing an acidic copper plating additive for thickening composite copper foil, comprising the following steps: Step 1: Add deionized water to a beaker, slowly add concentrated sulfuric acid to the water, stir and cool to room temperature; Step 2: Add polyether, stir until dissolved, and then dilute to the final volume with deionized water to obtain the acidic copper plating additive; the acidic copper plating additive includes the following components: 50 g / L polyether, 5 mL / L concentrated sulfuric acid, and the balance being deionized water; the polyether is a mixture of polyethylene glycol, polyoxyethylene polyoxypropylene ether, and polyoxyethylene ether sulfonate, with a mass ratio of 5:5:1. The application of acidic copper plating additives for thickening composite copper foil includes the following steps: S1: Take PET film as the base film, and after PVD treatment, form a copper conductive layer on the surface of the base film; S2: Preparation of copper plating solution: First, add deionized water to the copper plating tank, then slowly add concentrated sulfuric acid while stirring. After cooling to 40℃, slowly add copper oxide powder while stirring, and replenish deionized water to the calibration value. After cooling to 30℃, add 36% hydrochloric acid and acidic copper plating additive to obtain the copper plating solution. The copper plating solution includes the following components: 100mL / L concentrated sulfuric acid, 60g / L copper oxide, 60mg / L chloride ions and 5mL / L acidic copper plating additive; the concentrated sulfuric acid is 98% concentrated sulfuric acid, the copper oxide powder has a particle size of 100nm and a purity of 99%, and the chloride ions are sourced from 36% hydrochloric acid. S3: Electroplating: Immerse the base film obtained in S1 into the copper plating solution at a current density of 2ASD and electroplat for 150s to form a thickened copper layer. S4: Passivation and Drying: After passivation, the film obtained in S3 is dried at 100°C to obtain composite copper foil.

[0027] Example 3: A method for preparing an acidic copper plating additive for thickening composite copper foil, comprising the following steps: Step 1: Add deionized water to a beaker, slowly add concentrated sulfuric acid to the water, stir and cool to room temperature; Step 2: Add polyether, stir until dissolved, and then dilute to the final volume with deionized water to obtain the acidic copper plating additive; the acidic copper plating additive includes the following components: 50 g / L polyether, 5 mL / L concentrated sulfuric acid, and the balance is deionized water; the polyether is a mixture of polyethylene glycol, polyoxyethylene ether sulfonate and modified polyether, and the mass ratio of polyethylene glycol, polyoxyethylene ether sulfonate and modified polyether is 5:1:1; Modified polyethers are prepared by the following process: (1) Under nitrogen atmosphere, n-butanol and tris(pentafluorophenyl)borane were added to the reactor, heated to 110°C, and vacuumed to a pressure of 0.5 MPa for 60 min. Ethylene oxide and 1,2-epoxybutane were added to the reactor and reacted for 8 h to obtain the intermediate product. The molar ratio of n-butanol, tris(pentafluorophenyl)borane, ethylene oxide and 1,2-epoxybutane was 0.5:0.02:1:1. (2) Add cation exchange resin of type 001×7Na(732) and solvent dimethylformamide to the flask, and add the intermediate product obtained in step (1) and sodium isophthalate 5-sulfonic acid. Place the flask in a water bath at 60°C and heat and stir for 10 h to obtain modified polyether; the molar ratio of ethylene oxide, 1,2-epoxybutane, cation exchange resin and sodium isophthalate 5-sulfonic acid is 10:10:0.02:1. The application of acidic copper plating additives for thickening composite copper foil includes the following steps: S1: Preparation of base film: PP film is used as base film, and copper conductive layer is formed on the surface of the base film after PVD treatment; S2: Preparation of copper plating solution: First, add deionized water to the copper plating tank, then slowly add concentrated sulfuric acid while stirring. After cooling to 40℃, slowly add copper oxide powder while stirring, and replenish deionized water to the calibration value. After cooling to 30℃, add 36% hydrochloric acid and acidic copper plating additive to obtain the copper plating solution. The copper plating solution includes the following components: 120mL / L concentrated sulfuric acid, 30g / L copper oxide, 60mg / L chloride ions and 3mL / L acidic copper plating additive; the concentrated sulfuric acid is 98% concentrated sulfuric acid, the copper oxide powder has a particle size of 100nm and a purity of 99%, and the chloride ions are sourced from 36% hydrochloric acid. S3: Electroplating: Immerse the base film obtained in S1 into the copper plating solution at a current density of 2ASD and electroplat for 150s to form a thickened copper layer. S4: Passivation and Drying: After passivation, the film obtained in S3 is dried at 100°C to obtain composite copper foil.

[0028] Example 4: A method for preparing an acidic copper plating additive for thickening composite copper foil, comprising the following steps: Step 1: Add deionized water to a beaker, slowly add concentrated sulfuric acid to the water, stir and cool to room temperature; Step 2: Add polyether, stir until dissolved, and then dilute to the final volume with deionized water to obtain the acidic copper plating additive; the acidic copper plating additive includes the following components: 50 g / L polyether, 5 mL / L concentrated sulfuric acid, and the balance is deionized water; the polyether is a mixture of polypropylene glycol, polyoxyethylene ether sulfonate and modified polyether, and the mass ratio of polypropylene glycol, polyoxyethylene ether sulfonate and modified polyether is 6:1:1; Modified polyethers are prepared by the following process: (1) Under a vacuum nitrogen atmosphere, n-butanol and tris(pentafluorophenyl)borane were added to the reactor, heated to 120°C, and a vacuum was drawn to a pressure of 0.8 MPa for 45 min. Ethylene oxide and 1,2-epoxybutane were then added to the reactor and reacted for 9 h to obtain the intermediate product. The molar ratio of n-butanol, tris(pentafluorophenyl)borane, ethylene oxide and 1,2-epoxybutane was 0.2:0.03:1.5:1. (2) Add cation exchange resin of type 001×7Na(732) and solvent dimethylformamide to the flask, and add the intermediate product obtained in step (1) and sodium isophthalate 5-sulfonic acid. Place the flask in a water bath at 65°C and heat and stir for 9 hours to obtain modified polyether; the molar ratio of ethylene oxide, 1,2-epoxybutane, cation exchange resin and sodium isophthalate 5-sulfonic acid is 15:10:0.04:1. The application of acidic copper plating additives for thickening composite copper foil includes the following steps: S1: Preparation of base film: PP film is used as base film, and copper conductive layer is formed on the surface of the base film after PVD treatment; S2: Preparation of copper plating solution: First, add deionized water to the copper plating tank, then slowly add concentrated sulfuric acid while stirring. After cooling to 40℃, slowly add copper oxide powder while stirring, and replenish deionized water to the calibration value. After cooling to 30℃, add 36% hydrochloric acid and acidic copper plating additive to obtain the copper plating solution. The copper plating solution includes the following components: 120mL / L concentrated sulfuric acid, 30g / L copper oxide, 60mg / L chloride ions and 3mL / L acidic copper plating additive; the concentrated sulfuric acid is 98% concentrated sulfuric acid, the copper oxide powder has a particle size of 100nm and a purity of 99%, and the chloride ions are sourced from 36% hydrochloric acid. S3: Electroplating: Immerse the base film obtained in S1 into the copper plating solution at a current density of 2ASD and electroplat for 150s to form a thickened copper layer. S4: Passivation and Drying: After passivation, the film obtained in S3 is dried at 100°C to obtain composite copper foil.

[0029] Example 5: A method for preparing an acidic copper plating additive for thickening composite copper foil, comprising the following steps: Step 1: Add deionized water to a beaker, slowly add concentrated sulfuric acid to the water, stir and cool to room temperature; Step 2: Add polyether, stir until dissolved, and then dilute to the final volume with deionized water to obtain the acidic copper plating additive; the acidic copper plating additive includes the following components: 50 g / L polyether, 5 mL / L concentrated sulfuric acid, and the balance being deionized water; the polyether is a mixture of polyoxyethylene polyoxypropylene ether, polyoxyethylene ether sulfonate and modified polyether, and the mass ratio of polyoxyethylene polyoxypropylene ether, polyoxyethylene ether sulfonate and modified polyether is 6:1:1; Modified polyethers are prepared by the following process: (1) In a vacuum nitrogen environment, methanol and tris(pentafluorophenyl)borane were added to the reactor, heated to 130°C, and vacuum was drawn to a pressure of 1 MPa for 30 min. Ethylene oxide and 1,2-epoxybutane were added to the reactor and reacted for 8 h to obtain the intermediate product. The molar ratio of methanol, tris(pentafluorophenyl)borane, ethylene oxide and 1,2-epoxybutane was 0.1:0.02:2:1. (2) Add cation exchange resin of type 001×7Na(732) and solvent dimethylformamide to the flask, and add the intermediate product obtained in step (1) and sodium isophthalate 5-sulfonic acid. Place the flask in a water bath at 70°C and heat and stir for 8 hours to obtain modified polyether; the molar ratio of ethylene oxide, 1,2-epoxybutane, cation exchange resin and sodium isophthalate 5-sulfonic acid is 20:10:0.06:1. The application of acidic copper plating additives for thickening composite copper foil includes the following steps: S1: Preparation of base film: PP film is used as base film, and copper conductive layer is formed on the surface of the base film after PVD treatment; S2: Preparation of copper plating solution: First, add deionized water to the copper plating tank, then slowly add concentrated sulfuric acid while stirring. After cooling to 40℃, slowly add copper oxide powder while stirring, and replenish deionized water to the calibration value. After cooling to 30℃, add 36% hydrochloric acid and acidic copper plating additive to obtain the copper plating solution. The copper plating solution includes the following components: 120mL / L concentrated sulfuric acid, 30g / L copper oxide, 60mg / L chloride ions and 3mL / L acidic copper plating additive; the concentrated sulfuric acid is 98% concentrated sulfuric acid, the copper oxide powder has a particle size of 100nm and a purity of 99%, and the chloride ions are sourced from 36% hydrochloric acid. S3: Electroplating: Immerse the base film obtained in S1 into the copper plating solution at a current density of 2ASD and electroplat for 150s to form a thickened copper layer. S4: Passivation and Drying: After passivation, the film obtained in S3 is dried at 100°C to obtain composite copper foil.

[0030] Comparative Example 1: Based on Example 1, the acidic copper plating additive was replaced with 6050A, 6050B, and 6050MU. The only difference from Example 1 was: S2: Preparation of copper plating solution: First, deionized water was added to the copper plating tank, then concentrated sulfuric acid was slowly added while stirring. After cooling to below 40°C, copper oxide powder was slowly added while stirring, and deionized water was added to the calibration value. After cooling to below 30°C, 36% hydrochloric acid, 6050A, 6050B, and 6050MU were added to obtain the copper plating solution. The copper plating solution included the following components: 120 mL / L concentrated sulfuric acid, 30 g / L copper oxide, 60 mg / L chloride ions, 10 mL / L 6050A, 1 mL / L 6050B, and 8 mL / L 6050MU.

[0031] Comparative Example 2: Based on Example 2, the acidic copper plating additive was replaced with 6050A, 6050B, and 6050MU. The only difference from Example 1 was: S2: Preparation of copper plating solution: First, deionized water was added to the copper plating tank, then concentrated sulfuric acid was slowly added while stirring. After cooling to below 40°C, copper oxide powder was slowly added while stirring, and deionized water was added to the calibration value. After cooling to below 30°C, 36% hydrochloric acid, 6050A, 6050B, and 6050MU were added to obtain the copper plating solution. The copper plating solution included the following components: 100 mL / L concentrated sulfuric acid, 60 g / L copper oxide, 60 mg / L chloride ions, 10 mL / L 6050A, 1 mL / L 6050B, and 8 mL / L 6050MU.

[0032] Comparative Example 3: Based on Example 3, tris(pentafluorophenyl)borane was replaced with KOH. The only difference from Example 3 was that: (1) under nitrogen atmosphere, n-butanol and KOH were added to the reactor, heated to 110°C, vacuumed to a pressure of 0.5 MPa, maintained for 60 min, ethylene oxide and 1,2-epoxybutane were added to the reactor, and the reaction was carried out for 8 h to obtain the intermediate product; the molar ratio of n-butanol, KOH, ethylene oxide and 1,2-epoxybutane was 0.5:0.02:1:1.

[0033] Comparative Example 4: Based on Example 4, sodium 5-sulfonic acid isophthalate was replaced with sodium isophthalate. The only difference from Example 4 is that: (2) cation exchange resin of type 001×7Na(732) and solvent dimethylformamide were added to the flask, and the intermediate product obtained in step (1) and sodium isophthalate were added. The flask was placed in a water bath at 65°C and heated and stirred. The reaction was carried out for 9 hours to obtain modified polyether. The molar ratio of ethylene oxide, 1,2-epoxybutane, cation exchange resin and sodium isophthalate was 1.5:1:0.04:1.

[0034] Comparative Example 5: Based on Example 5, the modified polyether was replaced with silane-modified polyether.

[0035] Experiment: Composite copper foils obtained in Examples 1-5 and Comparative Examples 1-5 were used to prepare samples. Their properties were tested and the test results were recorded. Tensile strength range and variance test: The tensile strength was measured using a universal testing machine at a tensile speed of 5 mm / min, and the range and variance were calculated. Additive analysis: Single-component additives (Examples 1-5, Comparative Examples 3-5) were analyzed using a surface tension drop tester (surface tension was measured in 3 parallel measurements, and the total time was recorded); Three-component additives (Comparative Examples 1-2) were analyzed using CVS to determine the concentration of the three components, and the total time was recorded. Coating smoothness: The Ra value of the coating was measured at 5 random points using a surface roughness meter, and the average value was taken (unit: μm).

[0036]

[0037] Conclusion: As can be seen from the comparison of the data in the table, the coatings prepared in Examples 1-5 (single-component additives, Examples 3-5 containing modified polyethers) have significantly better overall performance than those in Comparative Examples 1-5; compared with Examples 1-2, Examples 3-5, which are single-component additives containing modified polyethers, have better coating smoothness. Comparative Examples 1-2: Using the traditional three-component additive (6050A / B / MU) requires CVS for multi-component analysis, which is time-consuming and costly. The performance of the resulting coating is significantly inferior to that of Examples 1-2, highlighting the advantages of the single-component additive in Examples 1-2 in terms of simplifying operation, reducing costs, and improving the stability of the plating solution. Comparative Examples 3-5: By changing the preparation conditions or composition of the modified polyether, the importance of key components in this invention was further verified: In Comparative Example 3, replacing the catalyst with tris(pentafluorophenyl)borane and KOH led to a decrease in the degree of polymerization and structural stability of the modified polyether; In Comparative Example 4, removing the sulfonic acid group (using sodium isophthalate) reduced the hydrophilicity and copper ion coordination ability of the modified polyether, making it unable to effectively inhibit copper ion precipitation, resulting in a decrease in coating performance; In Comparative Example 5, the use of silane-modified polyether was incompatible with the acidic copper plating system, leading to a deterioration in coating performance; These comparative results clearly demonstrate the necessity of specific catalysts, sulfonic acid groups, and polyether structures for optimizing coating performance; In summary, this invention effectively solves the problems of imbalance and oxidative decomposition of traditional multi-component additives by combining a single-component additive with modified polyether, reduces testing and production costs, and significantly improves the mechanical properties, smoothness and stability of the coating, thus showing good prospects for industrial application.

[0038] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.

Claims

1. An acidic copper plating additive for thickening composite copper foil, characterized in that: It comprises the following components: polyether, concentrated sulfuric acid, and deionized water; wherein the polyether is one or a mixture of two of conventional inhibitor polyether compounds and polyether sulfonates.

2. The acidic copper plating additive for thickening composite copper foil according to claim 1, characterized in that: The conventional inhibitor polyether compound is one or a mixture of polyethylene glycol, polypropylene glycol, and polyoxyethylene polyoxypropylene ether.

3. The acidic copper plating additive for thickening composite copper foil according to claim 1, characterized in that: The polyether sulfonate is one or a mixture of polyoxypropylene ether sulfonate, polyoxyethylene ether sulfonate, sodium polyetherimide sulfonate, and sodium polyetherimide sulfonate derivatives.

4. The acidic copper plating additive for thickening composite copper foil according to claim 1, characterized in that: The concentration of polyether in the acidic copper plating additive is 5-100 g / L.

5. The acidic copper plating additive for thickening composite copper foil according to claim 1, characterized in that: The concentration of concentrated sulfuric acid in the acidic copper plating additive is 1-20 mL / L.

6. The acidic copper plating additive for thickening composite copper foil according to claim 1, characterized in that: The polyether also contains a modified polyether, which is prepared by the following process: (1) In a vacuum nitrogen environment, add the initiator and catalyst to the reactor, heat to 110-130℃, maintain for 30-60 min, gradually add ethylene oxide and 1,2-epoxybutane to the reactor, react for 8-10 h to obtain the intermediate product; (2) Add cation exchange resin and dimethylformamide to the flask, and add the intermediate product obtained in step (1) and sodium isophthalate 5-sulfonic acid. Place the flask in a water bath and heat and stir to react, and obtain the modified polyether.

7. The acidic copper plating additive for thickening composite copper foil according to claim 6, characterized in that: The amount of modified polyether added is 5-20% of the total mass of the polyether.

8. A method for preparing an acidic copper plating additive for thickening composite copper foil, characterized in that: Includes the following steps: Step 1: Add deionized water to a beaker, slowly add concentrated sulfuric acid to the water, stir and cool to room temperature; Step 2: Add polyether, stir until dissolved, and dilute with deionized water to obtain acidic copper plating additive.

9. The application of acidic copper plating additives for thickening composite copper foil, characterized in that: Includes the following steps: S1: Preparation of base film: Take PP film or PET film as base film, and form a copper conductive layer on the surface of the base film through PVD treatment; S2: Prepare copper plating solution: First, add deionized water to the copper plating tank, then slowly add concentrated sulfuric acid while stirring. After cooling, slowly add copper oxide powder while stirring. After replenishing deionized water and cooling, add 36% hydrochloric acid and acidic copper plating additive to obtain the copper plating solution. S3: Electroplating: Immerse the base film obtained in S1 into the copper plating solution and electroplat for 1-5 minutes to form a thickened copper layer; S4: Passivation and Drying: The base film obtained in S3 is passivated and then dried to obtain composite copper foil.

10. The application of the acidic copper plating additive for thickening composite copper foil according to claim 9, characterized in that: The copper plating solution comprises the following components: 50-150 mL / L concentrated sulfuric acid, 25-100 g / L copper oxide, 40-100 mg / L chloride ions, and 2-15 mL / L acidic copper plating additive.

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