Special cyanide-free copper plating high-performance additive for copper foil and preparation method thereof

Abstract

The invention relates to the technical field of current collectors, in particular to a cyanide-free copper plating high-performance additive special for copper foil and a preparation method of the cyanide-free copper plating high-performance additive. According to the cyanide-free copper plating high-performance additive disclosed by the invention, the cyanide-free copper plating high-performance additive is obtained by adding the ethyl carbamate, the 4-piperidinecarboxylic acid and the 1, 2, 4-butantriol. And mixing the cyanide-free copper plating high-performance additive, copper pyrophosphate, potassium pyrophosphate, ammonium citrate and selenium dioxide to obtain the copper electroplating solution. And carrying out an electroplating process on the electrocoppering solution to obtain the composite copper film. By adding the cyanide-free copper plating high-performance additive special for the copper foil, the prepared composite copper film has good compactness and ductility, the production qualification rate can be effectively increased, and the technical requirements of copper foil copper electroplating in actual production are met.

Description

Technical Field

[0001] The invention relates to the technical field of current collectors, in particular to a high-performance cyanide-free copper plating additive specially used for copper foil and a preparation method thereof. Background Art

[0002] The current composite copper collector is usually made by magnetron or evaporation of copper on a plastic film, and then acid copper electroplating is performed to increase the thickness of the copper layer. In the acid copper electroplating process, cyanide-free organic additives are often used to obtain a copper layer with fine crystallization and high brightness, and the thickness of the electroplated copper layer is required to be at least 1 micron. Although these processes can produce a high-brightness copper layer, due to the need to add a large amount of organic brighteners in the electroplating solution, this leads to an increase in the brittleness and reduction of the elongation of the surface copper layer of the composite copper collector, and it is easy to be damaged during electroplating and subsequent processing. In addition, when the magnetron or evaporated copper film enters the acid copper solution, it will be corroded while being plated, which affects the compactness of the composite copper film and increases the risk of flash points appearing in the film layer. Therefore, the existing electroplating process not only makes the qualified rate and efficiency of the composite copper film low, but also needs to use a large amount of organic brighteners, which all affect the overall performance and production efficiency of the composite copper collector.

[0003] In order to overcome the defects of the prior art, the present invention provides a high-performance cyanide-free copper plating additive for copper foil and a preparation method thereof. Summary of the invention

[0004] The purpose of the present invention is to provide a high-performance cyanide-free copper plating additive for copper foil and a preparation method thereof, so as to solve the problems in the prior art.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0006] A high-performance cyanide-free copper plating additive for copper foil, wherein the contents of the components are as follows: by mass: 0.01-0.02 parts of ethyl carbamate, 0.1-0.2 parts of 4-piperidinic acid, 0.2-0.4 parts of 1,2,4-butanetriol, and 1000-1200 parts of deionized water.

[0007] More optimally, the method for preparing the high-performance additive for cyanide-free copper plating of copper foil comprises the following steps:

[0008] Step 1: dissolving ethyl carbamate in deionized water, stirring and dissolving until clear, to obtain an ethyl carbamate solution;

[0009] Step 2: weigh 4-piperidinic acid and set aside;

[0010] Step 3: dissolving 1,2,4-butanetriol in deionized water, stirring and dissolving until clear, to obtain a 1,2,4-butanetriol solution;

[0011] Step 4: Slowly add the 4-piperidinic acid weighed in step 2 to the 1,2,4-butanetriol solution in step 3, stir thoroughly to dissolve and mix, then slowly add the ethyl carbamate solution prepared in step 1, and finally make up to volume with deionized water, continue stirring until uniform, and obtain a high-performance additive for cyanide-free copper plating.

[0012] More optimally, in the prepared high-performance additive for cyanide-free copper plating, ethyl formate is 0.01-0.02 g / L, 4-piperidinic acid is 0.1-0.2 g / L, and 1,2,4-butanetriol is 0.2-0.4 g / L.

[0013] More optimally, in the prepared high-performance additive for cyanide-free copper plating, ethyl carbamate is 0.02 g / L, 4-piperidinylcarboxylic acid is 0.2 g / L, and 1,2,4-butanetriol is 0.4 g / L.

[0014] More optimally, the cyanide-free copper plating high-performance additive and the cyanide-free copper plating solution are mixed to obtain the electroplating copper plating solution.

[0015] More optimally, the cyanide-free copper plating solution includes 60-70 g / L copper pyrophosphate, 280-320 g / L potassium pyrophosphate, 20-25 g / L ammonium citrate, and 0.008-0.02 g / L selenium dioxide.

[0016] More optimally, the cyanide-free copper plating solution includes 70 g / L copper pyrophosphate, 320 g / L potassium pyrophosphate, 25 g / L ammonium citrate, and 0.02 g / L selenium dioxide.

[0017] More optimally, the copper electroplating solution is set at a temperature of 30-50°C, a pH value of 8-8.4, a film relative motion speed of 5-7 m / min, and a plating current density of 1.5-2 A / dm 2 The plating is carried out for 5-8 minutes under the conditions to obtain a composite copper film.

[0018] Beneficial effects of the present invention:

[0019] The present invention obtains a high-performance additive for cyanide-free copper plating by adding ethyl carbamate, 4-piperidinic acid and 1,2,4-butanetriol. The high-performance additive for cyanide-free copper plating, copper pyrophosphate, potassium pyrophosphate, ammonium citrate and selenium dioxide are then mixed to obtain a copper electroplating solution. The copper electroplating solution is subjected to an electroplating process to obtain a composite copper film. The present invention adds the additive to a weakly alkaline cyanide-free copper plating solution, which can greatly reduce the brittleness of the coating and improve the elongation of the film layer without changing the performance of the original plating solution, and the pH value of the plating solution is nearly neutral and will not corrode the magnetron or evaporated copper film, reduce the situation of anti-corrosion on the surface of the copper film, increase the density and elongation of the copper film, greatly improve the production qualification rate, and meet the technical requirements of copper foil electroplating in actual production. DETAILED DESCRIPTION

[0020] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present invention. In terms of mass parts, one part is 1g.

[0021] Example 1: Step 1: Dissolve 0.01 g of ethyl carbamate in 200 mL of deionized water, and stir to dissolve until clear to obtain an ethyl carbamate solution;

[0022] Step 2: weigh 0.1 g 4-piperidinic acid and set aside;

[0023] Step 3: Dissolve 0.2 g of 1,2,4-butanetriol in 500 mL of deionized water, and stir until the solution is clear to obtain a 1,2,4-butanetriol solution;

[0024] Step 4: Slowly add the 4-piperidinic acid weighed in step 2 to the 1,2,4-butanetriol solution in step 3, stir and dissolve, then slowly add the ethyl carbamate solution prepared in step 1, and finally dilute with 1000mL deionized water, and continue stirring until uniform to obtain a cyanide-free copper plating high-performance additive; wherein ethyl carbamate 0.01g / L, 4-piperidinic acid 0.1g / L, 1,2,4-butanetriol 0.2g / L;

[0025] Step 5: Mix 10 mL of a cyanide-free copper plating high-performance additive with 1 L of a cyanide-free copper plating solution to obtain an electroplating copper plating solution; wherein the cyanide-free copper plating solution comprises 60 g / L of copper pyrophosphate, 280 g / L of potassium pyrophosphate, 20 g / L of ammonium citrate, and 0.008 g / L of selenium dioxide;

[0026] Step 6: The electroplating copper solution is set at a temperature of 40°C, a pH value of 8.2, a film relative movement speed of 7m / min, and a plating current density of 2A / dm 2 The plating was carried out for 7 minutes under the conditions of to obtain a composite copper film.

[0027] Comparative Example 1: The preparation process of the high-performance additive for cyanide-free copper plating is removed, and the rest is the same as Example 1, and the specific steps are as follows: Step 1: The cyanide-free copper plating solution is placed at a temperature of 40°C, a pH value of 8.2, a film relative motion speed of 7m / min, and a plating current density of 2A / dm 2 The plating was carried out for 7 minutes under the conditions of , to obtain a composite copper film; wherein the cyanide-free copper plating solution included 60 g / L copper pyrophosphate, 280 g / L potassium pyrophosphate, 20 g / L ammonium citrate, and 0.008 g / L selenium dioxide.

[0028] Example 2: Step 1: Dissolve 0.02 g of ethyl carbamate in 200 mL of deionized water, and stir to dissolve until clear to obtain an ethyl carbamate solution;

[0029] Step 2: weigh 0.2 g 4-piperidinic acid and set aside;

[0030] Step 3: Dissolve 0.4 g of 1,2,4-butanetriol in 500 mL of deionized water, and stir until the solution is clear to obtain a 1,2,4-butanetriol solution;

[0031] Step 4: Slowly add the 4-piperidinic acid weighed in step 2 to the 1,2,4-butanetriol solution in step 3, stir and dissolve thoroughly, then slowly add the ethyl carbamate solution prepared in step 1, and finally dilute with 1000 mL of deionized water, and continue stirring until uniform to obtain a cyanide-free copper plating high-performance additive; wherein ethyl carbamate 0.02 g / L, 4-piperidinic acid 0.2 g / L, 1,2,4-butanetriol 0.4 g / L;

[0032] Step 5: Mix 10 mL of a cyanide-free copper plating high-performance additive with 1 L of a cyanide-free copper plating solution to obtain an electroplating copper plating solution; wherein the cyanide-free copper plating solution comprises 70 g / L of copper pyrophosphate, 320 g / L of potassium pyrophosphate, 25 g / L of ammonium citrate, and 0.02 g / L of selenium dioxide;

[0033] Step 6: The electroplating copper solution is set at a temperature of 50°C, a pH value of 8.2, a film relative movement speed of 5m / min, and a plating current density of 2A / dm 2 The plating was carried out for 7 minutes under the conditions of to obtain a composite copper film.

[0034] Comparative Example 2: The preparation process of the high-performance additive for cyanide-free copper plating is removed, and the rest is the same as Example 2, and the specific steps are as follows: Step 1: The cyanide-free copper plating solution is 50°C, the pH value is 8.2, the relative movement speed of the film is 7m / min, and the plating current density is 2A / dm 2 The plating was carried out for 7 minutes under the conditions of , to obtain a composite copper film; wherein the cyanide-free copper plating solution included 70 g / L copper pyrophosphate, 320 g / L potassium pyrophosphate, 25 g / L ammonium citrate, and 0.02 g / L selenium dioxide.

[0035] Example 3: Step 1: Dissolve 0.02 g of ethyl carbamate in 200 mL of deionized water, and stir to dissolve until clear to obtain an ethyl carbamate solution;

[0036] Step 2: weigh 0.2 g 4-piperidinic acid and set aside;

[0037] Step 3: Dissolve 0.4 g of 1,2,4-butanetriol in 500 mL of deionized water, and stir until the solution is clear to obtain a 1,2,4-butanetriol solution;

[0038] Step 4: Slowly add the 4-piperidinic acid weighed in step 2 to the 1,2,4-butanetriol solution in step 3, stir and dissolve thoroughly, then slowly add the ethyl carbamate solution prepared in step 1, and finally dilute with 1000 mL of deionized water, and continue stirring until uniform to obtain a cyanide-free copper plating high-performance additive; wherein ethyl carbamate 0.02 g / L, 4-piperidinic acid 0.2 g / L, 1,2,4-butanetriol 0.4 g / L;

[0039] Step 5: Mix 10 mL of a cyanide-free copper plating high-performance additive with 1 L of a cyanide-free copper plating solution to obtain an electroplating copper plating solution; wherein the cyanide-free copper plating solution comprises 70 g / L of copper pyrophosphate, 320 g / L of potassium pyrophosphate, 25 g / L of ammonium citrate, and 0.02 g / L of selenium dioxide;

[0040] Step 6: The electroplating copper solution is set at a temperature of 50°C, a pH value of 8.3, a film relative movement speed of 5m / min, and a plating current density of 1.5A / dm 2 The plating was carried out for 7 minutes under the conditions of to obtain a composite copper film.

[0041] Comparative Example 3: The preparation process of the high-performance additive for cyanide-free copper plating is removed, and the rest is the same as Example 3, and the specific steps are as follows: Step 1: The cyanide-free copper plating solution is heated to 50°C, the pH value is 8.3, the relative movement speed of the film is 5m / min, and the plating current density is 1.5A / dm 2 The plating was carried out for 7 minutes under the conditions of , to obtain a composite copper film; wherein the cyanide-free copper plating solution included 70 g / L copper pyrophosphate, 320 g / L potassium pyrophosphate, 25 g / L ammonium citrate, and 0.02 g / L selenium dioxide.

[0042] Example 4: Step 1: Dissolve 0.015 g of ethyl carbamate in 200 mL of deionized water, and stir to dissolve until clear to obtain an ethyl carbamate solution;

[0043] Step 2: weigh 0.15 g 4-piperidinic acid and set aside;

[0044] Step 3: Dissolve 0.3 g of 1,2,4-butanetriol in 500 mL of deionized water, and stir until the solution is clear to obtain a 1,2,4-butanetriol solution;

[0045] Step 4: Slowly add the 4-piperidinic acid weighed in step 2 to the 1,2,4-butanetriol solution in step 3, fully stir to dissolve and mix, then slowly add the ethyl carbamate solution prepared in step 1, and finally dilute with 1000mL of deionized water, and continue stirring until uniform to obtain a cyanide-free copper plating high-performance additive; wherein ethyl carbamate 0.015g / L, 4-piperidinic acid 0.15g / L, 1,2,4-butanetriol 0.3g / L;

[0046] Step 5: Mix 10 mL of a cyanide-free copper plating high-performance additive with 1 L of a cyanide-free copper plating solution to obtain an electroplating copper plating solution; wherein the cyanide-free copper plating solution comprises 65 g / L of copper pyrophosphate, 300 g / L of potassium pyrophosphate, 22 g / L of ammonium citrate, and 0.01 g / L of selenium dioxide;

[0047] Step 6: The electroplating copper solution is set at a temperature of 30°C, a pH value of 8.1, a film relative motion speed of 7m / min, and a plating current density of 2A / dm 2 The plating was carried out for 8 minutes under the conditions of to obtain a composite copper film.

[0048] Comparative Example 4: The preparation process of the high-performance additive for cyanide-free copper plating is removed, and the rest is the same as Example 4, and the specific steps are as follows: Step 1: The cyanide-free copper plating solution is conditioned at a temperature of 30°C, a pH value of 8.1, a film relative motion speed of 7m / min, and a plating current density of 2A / dm 2 The plating was performed for 8 minutes under the conditions of , to obtain a composite copper film; wherein the cyanide-free copper plating solution included 65 g / L copper pyrophosphate, 300 g / L potassium pyrophosphate, 22 g / L ammonium citrate, and 0.01 g / L selenium dioxide.

[0049] Example 5: Step 1: Dissolve 0.02 g of ethyl carbamate in 200 mL of deionized water, and stir to dissolve until clear to obtain an ethyl carbamate solution;

[0050] Step 2: weigh 0.1 g 4-piperidinic acid and set aside;

[0051] Step 3: Dissolve 0.3 g of 1,2,4-butanetriol in 500 mL of deionized water, and stir until the solution is clear to obtain a 1,2,4-butanetriol solution;

[0052] Step 4: Slowly add the 4-piperidinic acid weighed in step 2 to the 1,2,4-butanetriol solution in step 3, fully stir to dissolve and mix, then slowly add the ethyl carbamate solution prepared in step 1, and finally dilute with 1000mL deionized water, and continue stirring until uniform to obtain a cyanide-free copper plating high-performance additive; wherein ethyl carbamate 0.02g / L, 4-piperidinic acid 0.1g / L, 1,2,4-butanetriol 0.3g / L;

[0053] Step 5: Mix 10 mL of a cyanide-free copper plating high-performance additive with 1 L of a cyanide-free copper plating solution to obtain an electroplating copper plating solution; wherein the cyanide-free copper plating solution comprises 70 g / L of copper pyrophosphate, 280 g / L of potassium pyrophosphate, 25 g / L of ammonium citrate, and 0.02 g / L of selenium dioxide;

[0054] Step 6: The electroplating copper solution is set at a temperature of 50°C, a pH value of 8.3, a film relative movement speed of 6m / min, and a plating current density of 1.5A / dm 2 The plating was carried out for 5 minutes under the conditions of to obtain a composite copper film.

[0055] Comparative Example 5: The preparation process of the high-performance additive for cyanide-free copper plating is removed, and the rest is the same as Example 5, and the specific steps are as follows: Step 1: The cyanide-free copper plating solution is heated to 50°C, the pH value is 8.3, the relative movement speed of the film is 6m / min, and the plating current density is 1.5A / dm 2 The plating was carried out for 5 minutes under the conditions of , to obtain a composite copper film; wherein the cyanide-free copper plating solution included 70 g / L copper pyrophosphate, 280 g / L potassium pyrophosphate, 25 g / L ammonium citrate, and 0.02 g / L selenium dioxide.

[0056] Example 6: Step 1: Dissolve 0.016 g of ethyl carbamate in 200 mL of deionized water, and stir to dissolve until clear to obtain an ethyl carbamate solution;

[0057] Step 2: weigh 0.16 g 4-piperidinic acid and set aside;

[0058] Step 3: Dissolve 0.35 g of 1,2,4-butanetriol in 500 mL of deionized water, and stir until the solution is clear to obtain a 1,2,4-butanetriol solution;

[0059] Step 4: Slowly add the 4-piperidinic acid weighed in step 2 to the 1,2,4-butanetriol solution in step 3, stir and dissolve thoroughly, then slowly add the ethyl carbamate solution prepared in step 1, and finally dilute with 1000mL of deionized water, and continue stirring until uniform to obtain a cyanide-free copper plating high-performance additive; wherein ethyl carbamate is 0.016g / L, 4-piperidinic acid is 0.16g / L, and 1,2,4-butanetriol is 0.35g / L;

[0060] Step 5: Mix 10 mL of a cyanide-free copper plating high-performance additive with 1 L of a cyanide-free copper plating solution to obtain an electroplating copper plating solution; wherein the cyanide-free copper plating solution comprises 68 g / L of copper pyrophosphate, 310 g / L of potassium pyrophosphate, 23 g / L of ammonium citrate, and 0.018 g / L of selenium dioxide;

[0061] Step 6: The electroplating copper solution is set at a temperature of 48°C, a pH value of 8.3, a film relative motion speed of 6m / min, and a plating current density of 2A / dm 2 The plating was carried out for 6 minutes under the conditions of to obtain a composite copper film.

[0062] Comparative Example 6: The preparation process of the high-performance additive for cyanide-free copper plating is removed, and the rest is the same as Example 6, and the specific steps are as follows: Step 1: The cyanide-free copper plating solution is heated to 48°C, the pH value is 8.3, the relative movement speed of the film is 6m / min, and the plating current density is 2A / dm 2 The plating was carried out for 6 minutes under the conditions of , to obtain a composite copper film; wherein the cyanide-free copper plating solution included 68 g / L copper pyrophosphate, 310 g / L potassium pyrophosphate, 23 g / L ammonium citrate, and 0.018 g / L selenium dioxide.

[0063] Example 7: Step 1: Dissolve 0.013 g of ethyl carbamate in 200 mL of deionized water, and stir to dissolve until clear to obtain an ethyl carbamate solution;

[0064] Step 2: weigh 0.13 g 4-piperidinic acid and set aside;

[0065] Step 3: Dissolve 0.26 g of 1,2,4-butanetriol in 500 mL of deionized water, and stir until the solution is clear to obtain a 1,2,4-butanetriol solution;

[0066] Step 4: Slowly add the 4-piperidinic acid weighed in step 2 to the 1,2,4-butanetriol solution in step 3, stir and dissolve thoroughly, then slowly add the ethyl carbamate solution prepared in step 1, and finally dilute with 1000 mL of deionized water, and continue stirring until uniform to obtain a cyanide-free copper plating high-performance additive; wherein ethyl carbamate is 0.013 g / L, 4-piperidinic acid is 0.13 g / L, and 1,2,4-butanetriol is 0.26 g / L;

[0067] Step 5: Mix 10 mL of a cyanide-free copper plating high-performance additive with 1 L of a cyanide-free copper plating solution to obtain an electroplating copper plating solution; wherein the cyanide-free copper plating solution comprises 65 g / L of copper pyrophosphate, 300 g / L of potassium pyrophosphate, 20 g / L of ammonium citrate, and 0.015 g / L of selenium dioxide;

[0068] Step 6: The electroplating copper solution is set at a temperature of 50°C, a pH value of 8.4, a film relative movement speed of 7m / min, and a plating current density of 1.5A / dm 2 The plating was carried out for 5 minutes under the conditions of to obtain a composite copper film.

[0069] Comparative Example 7: The preparation process of the high-performance additive for cyanide-free copper plating is removed, and the cyanide-free copper plating solution is replaced with an acidic copper foil plating solution purchased on the market. The rest is basically the same as Example 7, and the specific steps are as follows: Step 1: The acidic copper foil plating solution purchased on the market is conditioned at a temperature of 25°C, a pH value of 0.8, a film relative motion speed of 7m / min, and a plating current density of 1.5A / dm 2The plating was carried out for 5 minutes under the conditions of to obtain a composite copper film; wherein the acidic copper foil plating solution included 110 g / L copper sulfate pentahydrate, 150 g / L analytical pure sulfuric acid, 50 ppm chloride ions, and 10 ml / L 2-mercaptobenzimidazole.

[0070] Detection test:

[0071] Composite copper film elongation test: The composite copper film prepared by the present invention is used as a sample, baked at 150°C for 3 minutes, and cut into 15mm wide copper film strips in the MD or TD direction. The edge cut of the strip to be tested should not have gaps, burrs, and the film surface should not have soft or hard defects. Set the parameters of the product to be tested and the running speed of the tensile machine to 50MM / min and the stretching distance to 50MM on the computer. The copper film strip is clamped and tensioned on the tensile machine, and the sample to be tested is placed in the upper and lower chucks and tightened. Then perform a tensile test. According to the computer display data: the elongation in the MD or TD direction is greater than or equal to 3% and is qualified, and less than 3% is unqualified.

[0072] Composite copper film density test: dark room backlight board, sample copper film close to ordinary plane backlight (brightness 1200ml), sample length and width larger than the backlight board 30*30CM, vertical angle photo shows the brightness of the light spot; less than or equal to 10% of the light spots per square meter is qualified, more than 10% is unqualified. The results are as follows:

[0073] <![CDATA[Composite Copper film Elongation rate / (%)]]> <![CDATA[Composite Copper film Density / (%)]]> Example 1 10 0.5 Comparative Example 1 3 3 Example 2 15 0.3 Comparative Example 2 3.5 2.5 Example 3 15 0.3 Comparative Example 3 3.5 2.5 Example 4 13 0.6 Comparative Example 4 4.1 2.7 Example 5 14 0.2 Comparative Example 5 4.6 2.7 Example 6 14 0.4 Comparative Example 6 4.5 2.6 Example 7 15 0.45 Comparative Example 7 3.1 3

[0074] Conclusion: It can be seen from the above data that by adding the high-performance additive for cyanide-free copper plating prepared by the present invention, the performance of the original cyanide-free copper plating solution is not adversely affected, and the elongation of the composite copper film can be effectively improved. In addition, the pH value of the cyanide-free copper plating solution is close to neutral, and it will not corrode the magnetron or evaporated copper film, thereby effectively improving the density of the copper film, improving the production qualification rate, and meeting the technical needs of copper foil electroplating in actual production. At the same time, the additive prepared by the present invention has the characteristics of environmental protection, non-toxicity, low dosage concentration, low cost, etc., and is suitable for large-scale industrial production.

[0075] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process method article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process method article or device.

[0076] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A high-performance additive for cyanide-free copper plating of copper foil, characterized in that: The content of each component is: by mass: 0.01-0.02 parts of ethyl carbamate, 0.1-0.2 parts of 4-piperidinic acid, 0.2-0.4 parts of 1,2,4-butanetriol, and 1000-1200 parts of deionized water.

2. The method for preparing a high-performance cyanide-free copper plating additive for copper foil according to claim 1, characterized in that: The following steps are involved: Step 1: dissolving ethyl carbamate in deionized water, stirring and dissolving until clear, to obtain an ethyl carbamate solution; Step 2: weigh 4-piperidinic acid and set aside; Step 3: dissolving 1,2,4-butanetriol in deionized water, stirring and dissolving until clear, to obtain a 1,2,4-butanetriol solution; Step 4: Slowly add the 4-piperidinic acid weighed in step 2 to the 1,2,4-butanetriol solution in step 3, stir thoroughly to dissolve and mix, then slowly add the ethyl carbamate solution prepared in step 1, and finally make up to volume with deionized water, continue stirring until uniform, and obtain a high-performance additive for cyanide-free copper plating.

3. The method for preparing a high-performance cyanide-free copper plating additive for copper foil according to claim 2, characterized in that: In the prepared cyanide-free copper plating high-performance additive, ethyl formate is 0.01-0.02 g / L, 4-piperidinic acid is 0.1-0.2 g / L, and 1,2,4-butanetriol is 0.2-0.4 g / L.

4. The method for preparing a high-performance cyanide-free copper plating additive for copper foil according to claim 3, characterized in that: In the prepared high-performance additive for cyanide-free copper plating, ethyl carbamate is 0.02 g / L, 4-piperidinic acid is 0.2 g / L, and 1,2,4-butanetriol is 0.4 g / L.

5. A copper electroplating solution prepared based on the high-performance cyanide-free copper plating additive for copper foil according to claim 4, characterized in that: The cyanide-free copper plating high-performance additive and the cyanide-free copper plating solution are mixed to obtain an electroplating copper plating solution.

6. The copper electroplating solution prepared by the high-performance cyanide-free copper plating additive for copper foil according to claim 5, characterized in that: The cyanide-free copper plating solution includes 60-70 g / L copper pyrophosphate, 280-320 g / L potassium pyrophosphate, 20-25 g / L ammonium citrate, and 0.008-0.02 g / L selenium dioxide.

7. The copper electroplating solution prepared by the high-performance cyanide-free copper plating additive for copper foil according to claim 6, characterized in that: The cyanide-free copper plating solution includes 70 g / L copper pyrophosphate, 320 g / L potassium pyrophosphate, 25 g / L ammonium citrate, and 0.02 g / L selenium dioxide.

8. The copper electroplating solution prepared by the high-performance cyanide-free copper plating additive for copper foil according to claim 5, characterized in that: The copper electroplating solution is plated for 5-8 minutes at a temperature of 30-50°C, a pH value of 8-8.4, a film relative movement speed of 5-7m / min, and a plating current density of 1.5-2A / dm2 to obtain a composite copper film.