CN104002515B - Composite double-sided black copper foil and manufacturing method thereof - Google Patents

Abstract

The composite double-sided black copper foil comprises a copper foil and two blackening treatment layers, wherein the copper foil is provided with a bright surface and a dark surface, the two blackening treatment layers are respectively arranged on the bright surface and the dark surface, the two blackening treatment layers are alloy layers formed by electroplating in an electroplating bath containing copper ions, cobalt ions, nickel ions, manganese ions, magnesium ions and sodium ions, and a coarsening layer is selectively arranged between the two blackening treatment layers and the bright surface and the dark surface of the copper foil. Therefore, the two sides of the copper foil present a dark black appearance, are uniform, have no speckles, have no dusting, have good etching performance, can effectively block electromagnetic waves, near infrared rays, stray light, external light and the like, and can be directly subjected to a laser drilling process due to strong light absorption capacity. The invention also provides a manufacturing method of the composite double-sided black copper foil.

Description

Composite double-sided black copper foil and manufacturing method thereof

technical field

The invention relates to a copper foil with a blackened surface (layer), in particular to a composite double-sided black copper foil with a double-sided blackened surface (layer) and a manufacturing method thereof.

Background technique

In recent years, plasma display panels (PDPs), which are characterized by easy enlargement of the screen and high driving speed, are being widely used in various display devices.

Generally speaking, the plasma display panel utilizes gas discharge to generate plasma, and excites phosphors disposed in cells to generate light in the visible region through the generated line spectrum in the ultraviolet region. However, in the process of generating plasma by gas discharge, not only a line spectrum is generated in the ultraviolet region, but even a line spectrum with a wide range of wavelengths is generated in the near-infrared region. It should be mentioned that the above-mentioned wavelengths in the near-infrared region are close to the wavelengths used in optical communication. If they are close to each other, there will be problems of malfunction, and problems of generating microwaves or ultra-low frequency electromagnetic waves.

In order to block the leakage of this kind of electromagnetic wave or line spectrum in the near-infrared region, a shielding layer made of copper foil is generally installed in front of the panel. Usually, the copper foil is formed by etching into a thin wire mesh Shield. However, since the copper foil that forms the shielding layer is glossy, it will reflect the light from the outside of the panel, resulting in the deterioration of the picture contrast, and will reflect the light generated in the picture, thereby reducing the light transmittance, resulting in A problem that the visibility of the panel deteriorates.

In order to solve the above problems, it is necessary to implement blackening treatment on the copper foil shielding layer that can effectively shield electromagnetic waves or line spectrum leakage in the near infrared region; however, the known technologies only implement blackening treatment on a single side of the copper foil, so they can only solve The problem of shielding electromagnetic waves on one side of the copper foil causes the downstream process to blacken the other side of the copper foil, resulting in increased manufacturing costs. On the other hand, due to the high density, high performance and miniaturization of electronic components, the wiring of printed circuit boards is also moving toward high density; compared with traditional mechanical drilling, laser drilling that can perform finer processing Holes have been widely used. However, since the reflectance of copper near the wavelength of 10 μm of the carbon dioxide laser is close to 100%, the laser processing efficiency of laser drilling of copper foil with the highly versatile carbon dioxide laser is extremely poor.

On the other hand, in the HDI process, the conformal mask (etching method) is used; some use the black brown treatment on the surface of the copper foil to form a fine black oxide layer structure with strong light absorption ability on the surface of the copper foil. , and those who can directly perform high-efficiency laser drilling; some use copper foil thinning and then laser drilling, but the above methods still have problems such as poor production efficiency, complicated production management, and high production costs.

Contents of the invention

In view of the above shortcomings, the inventors have used many years of work experience and researched, experimented and discussed the above-mentioned problems to be solved, and found that after washing both sides of the copper foil with an acidic solution of copper sulfate to remove the dirt or filth attached to the surface , and then apply electroplating on both sides with a copper sulfate electroplating bath, and then apply black electroplating treatment on both sides. The shape of the copper foil before black electroplating and the form of black electroplating treatment will affect the color and uniformity of the black coating. Based on This idea completes the present invention.

The purpose of the present invention is to provide a composite double-sided black copper foil, which is characterized in that blackening treatment is applied to both sides of the copper foil at the same time, so that both the bright side and the dark side have a thick black appearance, uniform and no streaks, No powder falling, good etching performance, suitable for plasma display panel (PDP), electromagnetic wave shielding (EMI), high density printed circuit board (HDI) process, direct laser drilling process, inner layer board process, flexible copper foil substrate (FCCL), flexible printed circuit board (FPC).

According to an embodiment of the present invention, the composite double-sided black copper foil includes a copper foil and two blackened layers; the copper foil has a bright side and a dark side, and the two blackened layers are respectively arranged on The bright side and the dark side, and the two blackening treatment layers are alloy layers formed by electroplating in an electroplating bath containing copper ions, cobalt ions, nickel ions, manganese ions, magnesium ions and sodium ions.

In one embodiment of the present invention, it further includes two roughening layers, respectively arranged between one of the two blackening treatment layers and the bright surface and between the other one of the two blackening treatment layers and the Between the dark sides.

The method for manufacturing the composite double-sided black copper foil includes the following steps: firstly, providing a copper foil having a bright side and a dark side; then, treating the bright side and the dark side of the copper foil with an acidic solution; and then , forming a first roughening layer on the bright side, and forming a second roughening layer on the dark side; then, forming a first blackening treatment layer on the first roughening layer, and forming a second blackening treatment layer On the second roughened layer, wherein the first blackening treatment layer and the second blackening treatment layer are electroplated in an electroplating bath containing copper ions, cobalt ions, nickel ions, manganese ions, magnesium ions and sodium ions Alloy layer formed.

In summary, the composite double-sided black copper foil of the present invention has a blackening treatment layer formed by electroplating in an electroplating bath containing copper ions, cobalt ions, nickel ions, manganese ions, magnesium ions and sodium ions. Both surfaces of the copper foil have a thick black appearance, which can effectively suppress the reflection of light incident from the outside of the panel and the reflection of light emitted from the plasma display panel (light generated in the screen), so as to improve the contrast of the screen and The visibility of the display panel.

Furthermore, the blackened treatment layer has excellent shielding properties, can effectively block electromagnetic waves, near-infrared rays, stray light and external light, etc., and is suitable for plasma display panels (PDP), electromagnetic wave shielding (EMI), high-density printed circuit board (HDI) process, direct laser drilling process, inner layer board process, flexible copper clad substrate (FCCL), flexible printed circuit board (FPC), etc.

Description of drawings

Fig. 1 is the schematic flow sheet of the manufacturing method of composite double-sided black copper foil of the present invention;

Fig. 2 is a schematic cross-sectional view of the composite double-sided black copper foil of the present invention;

3A is a scanning electron microscope image of the bright side of the composite double-sided black copper foil according to Example 1 of the present invention;

Figure 3B is a scanning electron micrograph of the dark side of the composite double-sided black copper foil according to Example 1 of the present invention; and

4 is a schematic cross-sectional view of a composite double-sided black copper foil according to Example 7 of the present invention.

Wherein, the reference signs are explained as follows:

1 Composite double-sided black copper foil

10 copper foil

11 bright surface

12 dark side

20 coarse layers

21 first coarsening layer

22 second coarsening layer

30 blackened treatment layers

31 The first blackening treatment layer

32 second blackening treatment layer

40 anti-rust layers

41 first anti-rust layer

42 second anti-rust layer

50 silane treatment layers

detailed description

Please refer to Fig. 1 and 2 of the present invention, wherein Fig. 1 shows the schematic flow chart of the manufacturing method of the composite double-sided black copper foil of the present invention, and Fig. 2 shows the composition of the composite double-sided black copper foil made by the manufacturing method Sectional schematic. The following examples and comparative examples will be used to illustrate the present invention in detail, but the scope of rights of the present invention is not limited by these examples.

Example 1

Step S10 is executed to provide a copper foil 10 having a shiny side 11 and a matte side 12 . In this specific embodiment, the thickness of the copper foil 10 is between 6 and 35 μm and the roughness (Rz) is below 1.5; The microstructure of the copper foil surface is in the form of fine grains, and its brightness and roughness are better, so it is commonly called the bright side 11; in addition, the microstructure of the copper foil surface on the other side close to the electroplating solution is columnar It is presented in the form of crystal, and its roughness is usually greater than that of the bright side and has a pink appearance, so it is commonly called the dark side 12 .

Step S11 is executed to clean the bright side 11 and the dark side 12 of the copper foil 10 with an acidic solution. Specifically, the acidic solution contains copper sulfate pentahydrate with a concentration of 255g/L and sulfuric acid with a concentration of 95g/L, and the cleaning time is 8 seconds to remove the shiny surface 11 and Dirt or filth on the dark side 12; and wash with water after the pickling is completed, so as to avoid residual acid solution on both sides of the copper foil 10 and affect subsequent processes.

Step S12 is executed to form the roughened layer 20 , including forming the first roughened layer 21 on the bright side 11 and forming the second roughened layer 22 on the dark side 12 . Specifically, the copper foil 10 is first placed in an electroplating bath containing copper sulfate pentahydrate with a concentration of 86g/L, sulfuric acid with a concentration of 95g/L, and sodium phosphotungstate octadecahydrate with a concentration of 15ppm for electroplating; The electroplating bath temperature is 25°C, the current density is between 10.8A/dm ² and 20.6A/dm ² (ampere/square inch), and the time is 6.5 seconds, so as to treat the bright side 11 and the dark side of the copper foil 10 Surface 12 is pretreated.

Next, electroplating was performed using the same electroplating bath after rinsing with water; where the electroplating was performed at a current density between 1.34A/dm ² and 2.59A/dm ² for 9.7 seconds to form a roughening consisting of copper, respectively. structure (not shown) on the bright side 11 and dark side 12 of the copper foil 10; similarly, after washing with water, use the same electroplating bath and conditions for electroplating, so as to form a complete roughened layer 20 on the copper foil 10 The bright side 11 and the dark side 12 improve the bonding strength between the composite double-sided black copper foil 1 and an external substrate (not shown).

Step S13 is executed to form the blackened layer 30 , including forming a first blackened layer 31 on the first roughened layer 21 , and forming a second blackened layer 32 on the second roughened layer 22 . Specifically, after washing with water, the copper foil 10 formed with a complete roughened layer 20 is placed into a layer containing copper sulfate pentahydrate with a concentration of 65 g/L and nickel sulfate hexahydrate with a concentration of 9 g/L. , cobalt sulfate heptahydrate with a concentration of 45g/L, manganese sulfate monohydrate with a concentration of 20g/L, magnesium sulfate heptahydrate with a concentration of 35g/L and sodium citrate dihydrate with a concentration of 95g/L Electroplating bath for electroplating.

In this embodiment, the electroplating bath temperature is 35°C, the pH value is 5.5, the current density is between 6A/dm2 and 8A/ ^dm2 , and the time is ¹⁵ seconds, so as to form a complete blackening treatment layer 30 On the first roughened layer 21 and the second roughened layer 22 , a deep black appearance is formed on both surfaces of the copper foil 10 . Furthermore, please refer to FIGS. 3A and 3B , which show that the appearance of the first blackened layer 31 and the second blackened layer 32 is uniform without streaks and powder falling.

Step S14 is executed to form the antirust layer 40 , including forming a first antirust layer 41 on the first blackened layer 31 , and forming a second antirust layer 42 on the second blackened layer 32 . Specifically, after washing with water first, the copper foil 10 formed with a complete roughening layer 20 and blackening treatment layer 30 is placed in zinc sulfate heptahydrate with a concentration of 3 g/L and a concentration of 2 g/L. chromic acid and a concentration of 25g/L of liquid caustic soda for electroplating; wherein the electroplating bath temperature is 60°C, the current density is 1A/dm ² and the time is 7 seconds, so as to form a complete anti-rust layer 40. On the first blackened treatment layer 31 and the second blackened treatment layer 32 , an anti-rust function is added to the copper foil 10 .

Step S15 is executed to form a silane treatment layer 50 on one of the first anti-rust layer 41 and the second anti-rust layer 42 . Specifically, after cleaning with water first, spray and coat the first antirust layer 41 or the second antirust layer 42 with 0.5wt% (weight percentage concentration) of 3-aminotrimethylsilane aqueous solution, and then Baking in an oven at a temperature of 150° C. for 8 seconds is used to form the silane treatment layer 50 on the first anti-rust layer 41 or the second anti-rust layer 42 .

It is added that, according to the needs of practical applications, the silane treatment layer 50 of the present invention can be used as an insulating coating, an optical coating, a release coating, an anti-fog coating, etc., or add hydrophilicity to the modified surface , hydrophobicity, directionality, absorption and charge transport functions. The characteristics of the composite double-sided blackened copper foil obtained through the above steps are shown in Table 2.

Example 2

The difference between embodiment 2 and embodiment 1 lies in step S12, and other steps are the same as embodiment 1. Specifically, the copper foil 10 is first placed into an electroplating bath containing copper sulfate pentahydrate with a concentration of 86g/L, sulfuric acid with a concentration of 95g/L, and arsenic trioxide with a concentration of 400ppm for electroplating; wherein the bath temperature of electroplating is 25°C, the current density is between 13.8A/dm ² and 22.6A/dm ² and the time is 6.5 seconds, so as to pretreat the bright side 11 and the dark side 12 of the copper foil 10 .

Then, electroplating was performed using the same electroplating bath after rinsing with water; where the electroplating was performed at a current density between ^1.74A /dm2 and ^2.89A /dm2 for 9.7 seconds to form a roughened structure composed of copper, respectively on the bright side 11 and the dark side 12 of the copper foil 10. Similarly, after washing with water, use the same electroplating bath and conditions for electroplating, so as to form a complete roughened layer 20 on the bright side 11 and dark side 12 of the copper foil 10, thereby improving the composite double-sided black copper foil 1 and - The bond strength of the outer substrate.

More specifically, in Example 2, the composition of the electroplating bath and the electroplating conditions were changed. The characteristics of the composite double-sided blackened copper foil obtained through the above steps are shown in Table 2.

Example 3

The difference between embodiment 3 and embodiment 1 lies in step S13, and the rest of the steps are the same as embodiment 1. Specifically, the copper foil 10 formed with a complete roughened layer 20 was placed into copper sulfate pentahydrate with a concentration of 55g/L, nickel sulfate hexahydrate with a concentration of 12g/L, and copper sulfate with a concentration of 45g/L. Cobalt sulfate heptahydrate, manganese sulfate monohydrate with a concentration of 20g/L, magnesium sulfate heptahydrate with a concentration of 35g/L and sodium citrate dihydrate with a concentration of 95g/L were used for electroplating.

In more detail, Example 3 reduces the concentration of copper sulfate pentahydrate in the electroplating bath and increases the concentration of nickel sulfate hexahydrate in the electroplating bath. The properties of the composite double-sided blackened copper foil 1 obtained through the above steps are shown in Table 2.

Example 4

The difference between embodiment 4 and embodiment 1 lies in step S13, and other steps are the same as embodiment 1. Specifically, the copper foil 10 formed with a complete roughened layer 20 was placed into copper sulfate pentahydrate with a concentration of 65g/L, nickel sulfate hexahydrate with a concentration of 9g/L, and copper sulfate with a concentration of 45g/L. Cobalt sulfate heptahydrate, a concentration of 27g/L manganese sulfate monohydrate, a concentration of 48g/L magnesium sulfate heptahydrate and a concentration of 95g/L sodium citrate dihydrate electroplating bath for electroplating.

In more detail, Example 4 increases both manganese sulfate monohydrate and magnesium sulfate heptahydrate concentrations in the electroplating bath. The properties of the composite double-sided blackened copper foil 1 obtained through the above steps are shown in Table 2.

Example 5

The difference between embodiment 5 and embodiment 1 lies in step S13, and other steps are the same as embodiment 1. Specifically, the copper foil 10 formed with a complete roughened layer 20 was placed into copper sulfate pentahydrate with a concentration of 65g/L, nickel sulfate hexahydrate with a concentration of 9g/L, and copper sulfate with a concentration of 45g/L. Cobalt sulfate heptahydrate, a concentration of manganese sulfate monohydrate of 20g/L, a concentration of magnesium sulfate heptahydrate of 35g/L and a concentration of sodium citrate dihydrate of 115g/L were used for electroplating.

In more detail, Example 5 increases the concentration of sodium citrate dihydrate in the plating bath. The properties of the composite double-sided blackened copper foil 1 obtained through the above steps are shown in Table 2.

Example 6

The difference between embodiment 6 and embodiment 1 lies in step S13, and other steps are the same as embodiment 1. Specifically, the copper foil 10 formed with a complete roughened layer 20 was placed into copper sulfate pentahydrate with a concentration of 65g/L, nickel sulfate hexahydrate with a concentration of 9g/L, and copper sulfate with a concentration of 38g/L. Cobalt sulfate heptahydrate, manganese sulfate monohydrate with a concentration of 20g/L, magnesium sulfate heptahydrate with a concentration of 48g/L and sodium citrate dihydrate with a concentration of 95g/L were used for electroplating.

In more detail, Example 6 reduces the concentration of cobalt sulfate heptahydrate in the electroplating bath. The properties of the composite double-sided blackened copper foil 1 obtained through the above steps are shown in Table 2.

Example 7

Please refer to FIG. 4 , the difference between embodiment 7 and embodiment 1 is that step S12 is not executed. Specifically, the copper foil 10 is placed in copper sulfate pentahydrate with a concentration of 70 g/L, nickel sulfate hexahydrate with a concentration of 12 g/L, cobalt sulfate heptahydrate with a concentration of 50 g/L, and a concentration of 25 g/L. /L manganese sulfate monohydrate, magnesium sulfate heptahydrate with a concentration of 40g/L and sodium citrate dihydrate with a concentration of 135g/L for electroplating.

Therefore, the composite double-sided blackened copper foil 1 of Example 7 is not formed with the first roughened layer 21 and the second roughened layer 22, but the first blackened treatment layer 31 is formed on the bright side 11 of the copper foil 10, The second blackened layer 32 is formed on the dark side 12 of the copper foil 10 , and the first blackened layer 31 and the second blackened layer 32 have richer blackness respectively.

Comparative example 1

The difference between Comparative Example 1 and Example 1 is that step S12 is not implemented, that is, no roughening layer 20 is formed, and the rest of the steps are the same as Example 1. The properties of the composite double-sided blackened copper foil 1 obtained through the above steps are shown in Table 2.

Comparative example 2

The difference between Comparative Example 2 and Example 1 lies in step S13, and the rest of the steps are the same as Example 1. Specifically, the copper foil 10 formed with a complete roughened layer 20 was placed into copper sulfate pentahydrate with a concentration of 65g/L, nickel sulfate hexahydrate with a concentration of 9g/L, and copper sulfate with a concentration of 45g/L. Cobalt sulfate heptahydrate, manganese sulfate monohydrate with a concentration of 20g/L, magnesium sulfate heptahydrate with a concentration of 35g/L and sodium citrate dihydrate with a concentration of 70g/L were used for electroplating.

In more detail, Comparative Example 2 reduces the concentration of sodium citrate dihydrate in the plating bath. The properties of the composite double-sided blackened copper foil 1 obtained through the above steps are shown in Table 2.

Comparative example 3

The difference between Comparative Example 3 and Example 1 lies in step S13, and the rest of the steps are the same as Example 1. Specifically, the copper foil 10 formed with a complete roughened layer 20 was placed into copper sulfate pentahydrate with a concentration of 65g/L, nickel sulfate hexahydrate with a concentration of 9g/L, and copper sulfate with a concentration of 45g/L. Cobalt sulfate heptahydrate, a concentration of 20g/L manganese sulfate monohydrate and a concentration of 95g/L sodium citrate dihydrate electroplating bath for electroplating.

In more detail, the electroplating bath of Comparative Example 3 did not contain magnesium sulfate heptahydrate. The properties of the composite double-sided blackened copper foil 1 obtained through the above steps are shown in Table 2.

It should be noted that if the concentration of copper sulfate pentahydrate in the electroplating bath is less than 40g/L, the black chroma will be insufficient; if it is greater than 80g/L, copper powder (powder falling) will occur. If the concentration of nickel sulfate hexahydrate is less than 5g/L, the black chroma will be insufficient; if it is greater than 15g/L, the etchability will be deteriorated. If the concentration of cobalt sulfate heptahydrate is less than 30g/L, the black chroma will be insufficient; if it is greater than 60g/L, streaks will occur. If the concentration of manganese sulfate monohydrate is less than 15g/L, the black chroma will be insufficient; if it is greater than 30g/L, copper powder (powder falling) will occur. If the concentration of magnesium sulfate heptahydrate is less than 20g/L, the black chroma will be insufficient; if it is greater than 50g/L, streaks will occur. If the concentration of sodium citrate dihydrate is less than 80g/L, the black chroma will be insufficient; if it is greater than 150g/L, precipitation will occur in the electroplating bath.

Furthermore, if the electroplating temperature is higher than 20°C, streaks will occur; if it is higher than 60°C, the black chroma will be insufficient. If the pH value is less than 4, the electroplating bath will produce precipitation; if it is greater than 7, the black chroma will be insufficient. If the current density is less than 3A/dm ² , the black chroma will be insufficient; if it is greater than 20A/dm ² , copper powder will fall off (powder drop). If the electroplating time is less than 10 seconds, the black chroma will be insufficient; if it is longer than 30 seconds, copper powder (powder fall) will occur.

Please refer to Tables 1 and 2 below. Table 1 shows the composition of the electroplating solution used in each embodiment of the present invention and each comparative example. FIG. 2 shows the physical properties of each embodiment of the present invention and each comparative example. Wherein, the physical property test items of each embodiment of the present invention and each comparative example include:

A. Appearance streaks: visually judge the black spots and stripes on the appearance surface.

B. Chromaticity Y value: Measured with a color difference meter.

C. Gloss: Measured with a gloss meter.

D. Powder fall: Press one side of the filter paper with your fingertips on the left side of the full width of the bright side 11 and dark side 12 of the copper foil 10, slide it from left to right for about 30 cm, and compare the tested filter paper with the sample card , to determine the grade.

<Evaluation Criteria for Powder Falling Level>

O:≦Level 1

△:≦Level 1-2

X:≦Level 2

E. Etching: The test piece is made into a line width/line spacing: 75/75 (μm), placed in an acid etching solution containing 265.9g/l of copper chloride, 150ml/l of hydrogen peroxide, and 224ml/l of HCl, at temperature After dipping at 55°C for 5 minutes, remove the film with 3% NaOH solution at 48°C. After washing with water, the nickel layer was electroplated, then sliced, and the burrs were observed by OM (optical microscope) and SEM (scanning electron microscope).

<Evaluation Criteria for Etching Level>

O: After etching, there is no residual burr phenomenon on the substrate.

△: After etching, there are some remaining burrs on the substrate.

X: After etching, there are many remaining burrs on the substrate.

Table 1:

Table 2:

It can be seen from this that the composite double-sided blackened copper foil 1 of Examples 1 to 6 of the present invention has excellent quality characteristics such as appearance black chroma, glossiness, powder falling and etchability, and the various characteristics of Comparative Examples, appearance, Properties such as black chroma and glossiness are inferior to those of the embodiment of the present invention.

Referring to FIG. 2 again, it shows a composite double-sided black copper foil 1 made by the above-mentioned composite double-sided black copper foil manufacturing method, which includes a copper foil 10, two roughened layers 20, and two blackened layers 30. Two antirust layers 40 and one silane treatment layer 50. Copper foil 10 has a bright side 11 and a dark side 12; two roughened layers 20 are respectively arranged on the bright side 11 and dark side 12; two blackened treatment layers 30 are respectively arranged on the two roughened layers 20, wherein, two black The chemical treatment layer 30 is an alloy layer formed by electroplating in an electroplating bath containing copper ions, cobalt ions, nickel ions, manganese ions, magnesium ions and sodium ions; two antirust layers 40 are respectively arranged on the two blackening treatment layers 30 ; and the silane treatment layer 50 is disposed on one of the two antirust layers 40 .

Specifically, the two blackening treatment layers 30 are composed of copper sulfate pentahydrate with a concentration of 65g/L, nickel sulfate hexahydrate with a concentration of 9g/L, and cobalt sulfate heptahydrate with a concentration of 45g/L. An alloy layer formed by electroplating an electroplating bath of 20g/L manganese sulfate monohydrate, a concentration of 35g/L magnesium sulfate heptahydrate and a concentration of 95g/L sodium citrate dihydrate; wherein the electroplating bath The temperature is 20° C. to 60° C., the pH value is 4 to 7, the time is 10 seconds to 30 seconds, and the current density is 3 amps/square inch to 20 amps/square inch.

Preferably, the thickness of the copper foil 10 is 6 to 35 μm, the roughness (Rz) of the bright side 11 of the copper foil 10 is 1.0 to 2.0, and the roughness of the dark side 12 of the copper foil 10 is 1.0 to 2.0. The chromaticity Y value of the two blackening treatment layers 30 measured by the color difference meter is 2 to 10, wherein it is preferably not more than 4; the gloss value of the two blackening treatment layers 30 measured by the gloss meter is 0.1 to 10, wherein Preferably no more than 1.

Through the above, compared with the traditional electrolytic copper foil with a single-sided black treatment surface (layer), the present invention has the following advantages: The manufacturing method of the composite double-sided black copper foil of the present invention can be achieved through special electrolytes and steps. Electrolytic treatment makes the two sides of the copper foil have the advantages of thick black appearance, uniform and no streaks, no powder falling, and good etching performance; moreover, the manufacturing method is to first wash off the two sides of the copper foil attached to the copper foil with an acidic solution After removing dirt or dirt, apply blackening treatment on both sides of the copper foil to form a blackening treatment layer with better color and uniformity.

As mentioned above, the blackening treatment layer of the present invention also has excellent shielding properties, which can effectively block electromagnetic waves, near infrared rays, stray light and external light, etc., so it is suitable for plasma display panels (PDP), electromagnetic wave shielding (EMI), High-density printed circuit board (HDI) process, direct laser drilling process, inner layer board process, flexible copper clad substrate (FCCL), flexible printed circuit board (FPC), etc.

The above descriptions are only preferred feasible embodiments of the present invention, and do not limit the patent scope of the present invention. Therefore, all equivalent technical changes made by using the description and illustrations of the present invention are included in the scope of the present invention.

Claims (11)

1. A composite double-sided black copper foil, characterized in that it comprises: a copper foil having a bright side and a dark side; and Two blackening treatment layers are arranged on the bright surface and the dark surface respectively, and the two blackening treatment layers are formed in an electroplating bath containing copper ions, cobalt ions, nickel ions, manganese ions, magnesium ions and sodium ions The alloy layer formed by electroplating is performed. 2. The composite double-sided black copper foil as claimed in claim 1, further comprising two roughened layers, which are respectively arranged between one of the two blackened treatment layers and the bright surface and on the bright side. Between the other one of the two blackened treatment layers and the dark side. 3. composite double-sided black copper foil as claimed in claim 2, is characterized in that, also comprises two antirust layers and a silane treatment layer, and described two antirust layers are respectively arranged on the described two blackening treatment layers , the silane treatment layer is disposed on one of the two antirust layers. 4. The composite double-sided black copper foil as claimed in claim 1, characterized in that, the two blackening treatment layers contain copper sulfate pentahydrate with a concentration of 40 to 80 g/L at the same time, and a concentration of 5 to 80 g/L. 15g/L nickel sulfate hexahydrate, 30-60g/L cobalt sulfate heptahydrate, 15-30g/L manganese sulfate monohydrate, 20-50g/L magnesium sulfate heptahydrate The alloy layer formed by electroplating in an electroplating bath with a concentration of 80-150 g/L sodium citrate dihydrate, wherein the electroplating bath temperature is 20°C to 60°C, the pH value is 4 to 7, and the time is 10 seconds to 30 seconds and a current density of 3 to 20 amps/square inch. 5. The composite double-sided black copper foil according to claim 1, wherein the thickness of the copper foil is 6 to 35 μm, the roughness of the bright side is 1.0 to 2.0, and the roughness of the dark side is 1.0 to 2.0. 6. The composite double-sided black copper foil as claimed in claim 1, characterized in that, the chromaticity Y value of the two blackened treatment layers measured by the color difference meter is 2 to 10, and the Y value measured by the gloss meter is 2 to 10. The gloss value of the two blackening treatment layers is 0.1 to 10. 7. A method for manufacturing a composite double-sided black copper foil, comprising the following steps: providing a copper foil having a bright side and a dark side; cleaning the bright side and the dark side of the copper foil with an acidic solution; forming a first roughening layer on the bright side, and forming a second roughening layer on the dark side; and forming a first blackened treatment layer on the first roughened layer, and forming a second blackened treatment layer on the second roughened layer, and the first blackened treatment layer and the second blackened treatment layer The layer is an alloy layer formed by electroplating in an electroplating bath containing copper ions, cobalt ions, nickel ions, manganese ions, magnesium ions and sodium ions. 8. The manufacturing method of composite double-sided black copper foil as claimed in claim 7, characterized in that, after the step of forming the first blackened treatment layer and the second blackened treatment layer, the following steps are further included: forming a first antirust layer on the first blackened layer, and forming a second antirust layer on the second blackened layer; and A silane treatment layer is formed on one of the first anti-rust layer and the second anti-rust layer. 9. The manufacturing method of composite double-sided black copper foil as claimed in claim 7, characterized in that, the first blackened treatment layer and the second blackened treatment layer simultaneously contain 40-80g/L Copper sulfate pentahydrate, nickel sulfate hexahydrate with a concentration of 5-15g/L, cobalt sulfate heptahydrate with a concentration of 30-60g/L, manganese sulfate monohydrate with a concentration of 15-30g/L, concentration An alloy layer formed by electroplating an electroplating bath of 20-50 g/L magnesium sulfate heptahydrate and a concentration of 80-150 g/L sodium citrate dihydrate, wherein the electroplating bath temperature is 20°C to 60°C, The pH is 4 to 7, the time is 10 seconds to 30 seconds, and the current density is 3 A/in2 to 20 A/in2. 10. The manufacturing method of composite double-sided black copper foil as claimed in claim 7, wherein the thickness of the copper foil is 6 to 35 μm, the roughness of the bright side is 1.0 to 2.0, and the roughness of the dark side is 1.0 to 2.0. The degree is 1.0 to 2.0. 11. The manufacturing method of composite double-sided black copper foil as claimed in claim 7, characterized in that the chromaticity Y value of the two blackened treatment layers measured by the color difference meter is 2 to 10, and the Y value measured by the gloss meter is 2 to 10. The measured gloss values of the two blackened layers range from 0.1 to 10.