KR102521234B1 - Indeterminate copper materials for electrolytic copper foil and method for preparing the same - Google Patents

Abstract

The present invention relates to an amorphous copper material for electrodeposited copper foil and a manufacturing method thereof. Specifically, the present invention relates to an amorphous copper material for electrodeposited copper foil, which not only has excellent dissolution performance when dissolved in an electrolyte solution for manufacturing electrodeposited copper foil, but also secures work stability during manufacturing electrodeposited copper foil and can reduce costs due to a simple manufacturing process, and a manufacturing method thereof. .

Description

Indeterminate copper materials for electrolytic copper foil and method for preparing the same}

The present invention relates to an amorphous copper material for electrodeposited copper foil and a manufacturing method thereof. Specifically, the present invention relates to an amorphous copper material for electrodeposited copper foil, which not only has excellent dissolution performance when dissolved in an electrolyte for manufacturing electrodeposited copper foil, but also secures work stability during manufacturing electrodeposited copper foil and can reduce costs due to a simple manufacturing process, and a manufacturing method thereof. .

Electrolytic copper foil is manufactured by a continuous plating method in which a large titanium drum is used as a cathode and slowly rotated in an electrolyte solution, for example copper sulfate solution, to obtain copper foil with precipitated copper. etc. are used.

1 is a flow chart of a raw material manufacturing process of a conventional linear copper material for electrodeposited copper foil, and FIG. 2 is a photograph of the external appearance and microstructure of a cut copper wire produced in a conventional raw material manufacturing process of a linear copper material for electrodeposited copper foil.

As shown in FIG. 1, the linear copper material for electrodeposited copper foil is manufactured as a wire rod through raw material supply and demand steps such as cathode or copper scrap, casting, casting + rolling, or casting + rolling + drawing of the raw material. It can be manufactured by a method including the step of doing, washing and cutting the manufactured wire rod, and the like. Meanwhile, the electrodeposited copper foil may be manufactured by dissolving the cut linear copper material, which is a raw material for the electrodeposited copper foil, in a sulfuric acid solution, which is an electrolyte.

A conventional method for manufacturing electrodeposited copper foil uses a linear copper material, which is a cut copper wire as shown in FIG. 2, as a material for a nuclear power plant defrost foil, and the cut linear copper material is manufactured by rolling, wire drawing, and cutting processes, followed by rolling and wire drawing. When exposed to oil components such as rolling oil and fresh oil, there is a problem in that the cost of the electrodeposited copper foil increases due to complicated processes such as necessarily requiring a washing process for degreasing.

In addition, the cut linear copper material is usually manufactured in a shape of 2 to 4 mm in diameter and 30 to 100 mm in length in order to improve dissolution performance for the electrolyte solution. In this case, during the electrolyte dissolution process, electrolyte circulation and air supply There is a problem in that the workability is deteriorated because the linear copper material cut into the lower part of the plate with a diameter of 10 mm provided in the lower part of the melting tank is missing.

Furthermore, the linear copper material is formed to an average level of 5 μm by crystal grain refinement as shown in FIG. 2 through continuous casting, rolling, and wire drawing processes. Oxidation of the surface of the linear copper material, that is, passivation, is accelerated by having a high grain boundary density, and as a result, there is a problem in that the solubility in the electrolyte solution is lowered.

Therefore, there is an urgent need for a copper material and a method for manufacturing the copper material that not only has excellent dissolution performance when dissolved in an electrolyte solution for manufacturing electrodeposited copper foil, but also secures work stability during manufacturing electrodeposited copper foil and can reduce costs through a simple manufacturing process.

An object of the present invention is to provide an amorphous copper material having excellent dissolution performance when dissolved in an electrolyte solution for manufacturing an electrodeposited copper foil and a method for manufacturing the same.

In addition, an object of the present invention is to provide an amorphous copper material and a method for manufacturing the same, which can reduce the cost of the electrodeposited copper foil by securing work stability and simplifying the manufacturing process when manufacturing the electrodeposited copper foil.

In order to solve the above problems, the present invention,

As an amorphous copper material for an electrodeposited copper foil, an amorphous copper material for an electrodeposited copper foil having an average grain size of 50 to 300 μm is provided.

Here, a monolithic copper material for electrodeposited copper foil having a bulk density of 1.0 to 3.0 g/cm ³ defined by Equation 1 below is provided.

[Equation 1]

Bulk density (g/cm ³ ) = total mass of amorphous copper material / 1000 (g/cm ³ )

Here, the total mass of the irregular copper material means the total mass of the irregular copper material filled in a cubic box having a width × length × height of 10 cm × 10 cm × 10 cm.

In addition, the irregularly shaped copper material has an irregularly shaped copper material for electrodeposited copper foil in which the longest axis, which is the largest long axis, is 10 mm or more among the long axes in an arbitrary cross section, and the shortest axis, which is the shortest short axis among the short axes in an arbitrary cross section, is 5 mm or less. provides

Furthermore, it provides an amorphous copper material for electrodeposited copper foil, characterized in that the longest axis is 10 to 75 mm and the shortest axis is 1 to 5 mm.

On the other hand, a method of manufacturing amorphous copper material for electrodeposited copper foil, comprising the steps of a) supply and demand of copper raw material, b) melting of the copper raw material, and c) manufacturing an irregular copper material through casting after melting the copper raw material. provides

Here, in the step c), the molten copper from the copper raw material is dispersed in the form of fine particles and precipitated in water in a water bath while cooling to produce an amorphous copper material. to provide.

In addition, in the step c), the molten copper from the copper source material is dropped from the molten metal nozzle onto the collision plate provided above the water tank to disperse it in the form of fine particles, precipitate it into the water contained in the water tank, and cool it to manufacture an irregular copper material. Characterized in that, it provides a method for manufacturing the amorphous copper material for the electrodeposited copper foil.

And, it provides a method for manufacturing the amorphous copper material for the electrodeposited copper foil, characterized in that the molten copper has a molten metal temperature of 1,090 to 1,400 ° C.

Furthermore, the method for manufacturing the irregular copper material for electrodeposited copper foil is provided, characterized in that the distance between the discharge port of the molten metal nozzle and the upper surface of the collision plate is 0.3 to 1.5 m.

In addition, it provides a method for manufacturing the amorphous copper material for the electrodeposited copper foil, characterized in that the oxygen content of the molten copper is 20 to 1,000 ppm.

The amorphous copper material for electrodeposited copper foil according to the present invention exhibits excellent dissolution performance such as a rapid dissolution rate and a large amount of dissolution content when dissolved in an electrolyte through a specific bulk density, crystal grain size and specific shape.

In addition, the amorphous copper material for electrodeposited copper foil according to the present invention secures work stability during manufacture of electrodeposited copper foil, and unlike linear copper materials, processes such as rolling, wire drawing, washing for degreasing, and cutting are unnecessary, so the manufacturing process is simple and the cost of electrodeposited copper foil is reduced. It shows excellent effect that can save money.

1 is a flow chart of a conventional linear copper material manufacturing process for electrodeposited copper foil.
2 is a picture of the external appearance and microstructure of a conventional linear copper material for electrodeposited copper foil.
3 is a flow chart of a manufacturing process of amorphous copper material for electrodeposited copper foil according to the present invention.
4 is a photograph of the external appearance and microstructure of an irregular copper material manufactured according to the manufacturing process of FIG. 3 .
FIG. 5 schematically illustrates a casting apparatus used in the process of manufacturing an irregular copper material for electrodeposited copper foil of FIG. 3 .
6 shows a shape in which a copper material is filled in a cubic-shaped acrylic box to measure bulk density.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiments described herein and may be embodied in other forms. Rather, the embodiments introduced herein are provided so that the disclosed content will be thorough and complete, and the spirit of the present invention will be sufficiently conveyed to those skilled in the art.

Figure 3 is a flow chart of a process for manufacturing an irregular copper material for electrodeposited copper foil according to the present invention, Figure 4 is a picture of the external appearance and microstructure of the irregular copper material manufactured according to the manufacturing process of Figure 3, Figure 5 is a irregular shape for electrodeposited copper foil of FIG. It schematically shows the appearance of a casting device used in the copper material manufacturing process. In addition, FIG. 6 shows a shape in which a copper material is filled in a cubic-shaped acrylic box to measure the bulk density.

As shown in FIG. 3, the monolithic copper material for electrodeposited copper foil may be manufactured by a manufacturing method including steps a) to c) below.

a) Supply and demand stage of raw materials such as copper cathode or scrap,

b) melting the supplied raw materials, and

c) manufacturing an irregular copper material through casting after melting the raw material.

Step c) may be performed using the casting apparatus shown in FIG. 5 . As shown in FIG. 5, copper melted at 1,090° C. or higher, preferably 1,090 to 1,400° C. after being refined is dropped from the molten metal nozzle onto the impact plate provided above the water tank, and the dropped molten copper is deposited on the impact plate. Upon impact, it is dispersed in all directions in the form of irregular fine particles having no specific shape due to impact during collision, and precipitates and cools in the water contained in the water tank to form an irregular copper material.

Here, if the molten copper temperature is less than 1,090 ° C, the molten metal may solidify in advance and the discharge port of the molten metal nozzle may be clogged or copper falling onto the collision plate may be fused to the collision plate. In the case of an excessive amount, there is a problem in that the molten copper in the form of fine particles dispersed in all directions by falling onto the collision plate is fused again to form an excessively coarse copper material.

In addition, the size of the irregular copper material produced can be adjusted by adjusting the distance between the discharge port of the molten metal nozzle through which molten copper is discharged from the lower part of the molten bath containing the molten copper and the upper surface of the collision plate to 0.3 to 1.5 m.

Here, when the distance between the discharge port of the molten metal nozzle and the upper surface of the impingement plate is less than 0.3 m, molten copper may not be sufficiently scattered from the impingement plate and an excessively coarse irregular copper material may be formed. If m is greater than m, there is a problem in that an excessively fine irregular copper material is formed because the molten copper scattered from the collision plate is scattered in an excessively fine formation.

Furthermore, the oxygen content of the molten copper melt may be adjusted to 20 to 1,000 ppm. Here, when the oxygen content of the molten metal is less than 20 ppm, it is difficult to control the shape of the irregular copper material formed from the scattered molten copper due to the inflow of a large amount of hydrogen in the molten metal, whereas when the oxygen content exceeds 1,000 ppm, irregular copper by cooling There is a problem in that it is difficult to control the shape of an amorphous copper material because a large amount of oxide is generated during solidification of the material.

The indeterminate copper material for electrodeposited copper foil of the present invention manufactured according to the above manufacturing method example means a copper material having an indeterminate shape that cannot be defined as a specific shape such as linear or circular.

Meanwhile, an electrodeposited copper foil may be manufactured by dissolving the amorphous copper material prepared as described above in a sulfuric acid electrolyte. As described above, irregular copper materials do not require rolling, drawing and cutting processes, unlike conventional linear copper materials, during manufacturing, and in particular, since rolling oil and drawing oil used during rolling and drawing are not used, a washing process for degreasing is also unnecessary. Since the process is greatly simplified, the manufacturing cost of the electrodeposited copper foil can be greatly reduced.

Here, as shown in FIG. 4, the irregular copper material has a coarse grain size of 50 to 300 μm on average, preferably 150 to 250 μm, and has a low grain boundary density, thereby delaying surface passivation and sufficient dissolution in the electrolyte. performance can be obtained.

On the other hand, when the average grain size is smaller than 50 μm, such as the conventional linear copper material shown in FIG. 2, passivation of the surface is accelerated by maintaining a high grain boundary density, resulting in deterioration in dissolution performance in the electrolyte.

The coarse crystal grain size of the irregular copper material is achieved by rapidly cooling molten copper in water as shown in FIG. 5 without going through a rolling and drawing process like the conventional linear copper material.

Here, the average grain size can be measured by inputting the microstructure pictures of the irregular-shaped copper material and the linear copper material taken with an optical microscope or an electron microscope into general-purpose software such as Image Analyzer, and the measurement of the average grain size is known to those skilled in the art. can be measured in a variety of ways.

In addition, the irregular copper material may have a bulk density of 1.0 to 3.0 g/cm ³ in the form of irregular particles having an unspecified shape, as shown in FIG. 4 . The present inventors experimentally found that the dissolution performance, such as a rapid dissolution rate and a large amount of dissolution content, is improved when the amorphous copper material produced has a certain level of crystal grain size, preferably additionally a certain level of bulk density, when dissolved in an electrolyte solution. As confirmed, the present invention was completed.

Here, the bulk density may mean the total mass of the copper material for a cubic volume of 10 cm × 10 cm × 10 cm in width × length × height, and may be defined by Equation 1 below.

[Equation 1]

Bulk density (g/cm ³ ) = total mass of copper material / 1000 (g/cm ³ )

Here, the total mass of the copper material means the total mass of the copper material filled in a cubic box having a width × length × height of 10 cm × 10 cm × 10 cm.

The total mass of the copper material is obtained by dropping the copper material into the cubic-shaped acrylic box from a height 5 cm away from the top of the cubic-shaped acrylic box having a size of 10 × 10 × 10 cm in width × length × height. It can be calculated by measuring the total mass of the copper material filled up to the top of the inside of the cubic-shaped acrylic box to the extent that the cover of can be completely closed. The width, length, and height of the cubic-shaped acrylic box are based on the dimensions inside the box. In the embodiment of the present invention, an acrylic box having a thickness of 5 mm was used, but the material and thickness of the box can maintain the cubic shape Not particularly limited.

In particular, when the bulk density of the amorphous copper material is less than 1.0 g/cm ³ , the surface area of the amorphous copper material in contact with the electrolyte increases, but there is a problem in that the content of copper actually dissolved in the electrolyte solution is insufficient. When g/cm ³ is greater than the copper content dissolved in the electrolyte is sufficient, but the surface area of the irregular copper material in contact with the electrolyte is less than the standard, so the dissolution rate may be greatly reduced.

In addition, the irregular copper material has a longest axis, which is the largest long axis, of 10 mm or more, preferably 10 to 75 mm, among the long axes in an arbitrary cross section, and the shortest axis, which is the shortest short axis in an arbitrary cross section, is 5 mm or less, preferably 1 to 5 mm.

If the longest axis is less than 10 mm, the copper material may come out to the lower part of the perforated plate with a diameter of 10 mm provided at the bottom of the electrolyte tank for electrolyte circulation and air supply during the electrolyte dissolution process, resulting in reduced workability. On the other hand, if the thickness is greater than 75 mm, the specific surface area of the copper material is insufficient, so the solubility in the electrolyte may be greatly reduced. On the other hand, when the shortest axis is greater than 5 mm, the specific surface area of the copper material is insufficient, and thus the solubility in the electrolyte may be greatly reduced.

Here, the longest axis and the shortest axis of the irregular copper material can be measured using an instrument such as a vernier caliper, and any instrument capable of measuring the length is not particularly limited.

[Example]

1. Production example of copper material

Examples 1 to 5, which have the characteristics shown in Table 1 below, by adjusting the temperature of the molten copper molten metal and the distance from the discharge port of the molten metal nozzle through which the molten copper is discharged to the collision plate using the casting apparatus shown in FIG. 5 An irregularly shaped copper material corresponding to 3 was manufactured.

In addition, for comparison with the above examples, linear copper materials corresponding to Comparative Examples 1 to 3 were prepared by casting, rolling, drawing, washing, and cutting the copper raw material.

Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 average grain
Size (μm) 189 195 177 5.8 7.0 10.4 size
(shortest axis×
longest axis, mm) 1×50 3×50 5×50 3.1 (diameter)
×80 (length) 4.2 (diameter)
×80 (length) 8.0 (diameter)
×90 (length) bulk density
(g/cm ³ ) 1.88 1.63 2.48 3.89 3.95 3.87

2. Evaluation of melting performance of copper materials

Copper materials according to Examples and Comparative Examples were precipitated in 1 L of a sulfuric acid solution at a temperature of 80° C. and a concentration of 150 g/L for 48 hours. Then, the weight of each sample was measured, and the amount of dissolution was calculated and recorded in Table 2 below.

division Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Weight before melting (g) 121.0 122.1 120.3 124.0 125.4 121.1 Weight after melting (g) 108.3 113.6 113.8 119.6 121.5 120.4 Dissolution amount (g/L) 12.7 8.5 6.5 4.4 3.9 0.7

As shown in Table 2, the amorphous copper materials of Examples 1 to 3 in which the bulk density was precisely controlled while maintaining a certain level of crystal grain size and shape of a specific size significantly improved dissolution performance such as dissolution rate and amount of dissolution. confirmed to be

On the other hand, the existing linear copper materials of Comparative Examples 1 to 3 had a bulk density exceeding the standard, so that the surface area of the copper material in contact with the electrolyte was less than the standard, so the dissolution rate was greatly reduced, and the average grain size was small, so it had a high grain boundary density. By doing so, it was confirmed that the passivation of the surface was accelerated and the solubility in the electrolyte was lowered.

Although this specification has been described with reference to preferred embodiments of the present invention, those skilled in the art can variously modify and change the present invention within the scope not departing from the spirit and scope of the present invention described in the claims described below. will be able to carry out Therefore, if the modified implementation basically includes the elements of the claims of the present invention, all of them should be considered to be included in the technical scope of the present invention.

Claims (10)

As an amorphous copper material for electrodeposited copper foil,
The average grain size is 50 to 300 μm,
Amorphous copper material for electrodeposited copper foil having a bulk density of 1.0 to 3.0 g/cm ³ defined by Equation 1 below.
[Equation 1]
Bulk density (g/cm ³ ) = total mass of amorphous copper material / 1000 (g/cm ³ )
Here, the total mass of the irregular copper material means the total mass of the irregular copper material filled in a cubic box having a width × length × height of 10 cm × 10 cm × 10 cm. delete According to claim 1,
The amorphous copper material,
Among the long axes in any cross section, the longest axis, which is the largest long axis, is 10 mm or more,
An irregularly shaped copper material for electrodeposited copper foil, wherein the shortest axis, which is the shortest axis among minor axes in an arbitrary cross section, is 5 mm or less. According to claim 3,
Amorphous copper material for electrodeposited copper foil, characterized in that the longest axis is 10 to 75 mm and the shortest axis is 1 to 5 mm. a) copper raw material supply and demand stage,
b) a melting step of melting the copper raw material to produce molten copper having a molten metal temperature of 1,090 to 1,400 ° C and an oxygen content of 20 to 1,000 ppm; and
c) manufacturing an irregular copper material by dispersing the molten copper in the form of fine particles by dropping the molten copper from a molten metal nozzle onto a collision plate provided above a water tank, precipitating it into water in the water tank, and cooling it;
The manufacturing method of the amorphous copper material for electrodeposited copper foil of claim 1, characterized in that the distance between the discharge port of the molten metal nozzle and the upper surface of the collision plate is 0.3 to 1.0 m. delete delete delete delete delete

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