Metal foil and metal-clad laminated plate

Abstract

The invention discloses a metal foil and a metal-clad laminate. The metal foil includes: a functional layer; the first anti-oxidation layer is arranged on one side of the functional layer; wherein the brightness value of the first side surface, far away from the functional layer, of the first anti-oxidation layer is less than or equal to 60, and the color difference on the first side surface is less than or equal to 1. The surface color of the copper foil is integrally grey and uniform, so that the non-uniformity of other colors is covered, and the uniformity of the surface color of the copper foil and the quality of a finished product are improved.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of electronic information materials, and in particular to a metal foil and a metal-clad laminate. Background Art

[0002] Electrolytic copper foil is a key material in high-frequency and high-speed printed circuit boards for 5G communication, and it plays a very important role. When electrolytic copper foil is subjected to roll plating, due to the process characteristics, stripes along the machine running direction are likely to be formed, or due to differences in the roughening process, different roughening stripe patterns are generated on the surface of the copper foil, making the appearance of the copper foil uneven and affecting the quality of the finished product. Summary of the Invention

[0003] The present invention provides a metal foil and a metal-clad laminate, which make the surface color of the copper foil turn gray and uniform as a whole, thereby covering the unevenness of other colors and improving the uniformity of the surface color of the copper foil and the quality of the finished product.

[0004] According to one aspect of the present invention, there is provided a metal foil, which includes:

[0005] A functional layer;

[0006] A first antioxidant layer disposed on one side of the functional layer;

[0007] Wherein, the brightness value of the first side of the first antioxidant layer away from the functional layer is less than or equal to 60, and the color difference on the first side is less than or equal to 1.

[0008] Optionally, the material of the first antioxidant layer includes: Zn and Ni;

[0009] The mass fraction ratio of Zn to Ni is 1:1 to 1:10.

[0010] Optionally, the mass fraction ratio of Zn to Ni is 1:2 to 1:3.

[0011] Optionally, the content of Ni is 1mg / m 2 ~100mg / m 2 .

[0012] Optionally, the metal foil further includes: a carrier layer;

[0013] The carrier layer is disposed on the side of the functional layer away from the first antioxidant layer.

[0014] Optionally, the metal foil further includes: a release layer;

[0015] The release layer is disposed between the carrier layer and the functional layer.

[0016] Optionally, the metal foil further includes: a second antioxidant layer;

[0017] The second antioxidant layer is disposed on a side of the functional layer away from the first antioxidant layer.

[0018] Optionally, the material of the second antioxidant layer includes: Zn and Ni;

[0019] The mass fraction ratio of Zn to Ni is 1:1 to 1:10.

[0020] Optionally, the mass fraction ratio of Zn to Ni is 1:2 to 1:3.

[0021] According to another aspect of the present invention, there is also provided a metal-clad laminate, which includes the metal foil according to any one of the above aspects.

[0022] The technical solution of the embodiment of the present invention provides a metal foil, which includes: a functional layer; a first antioxidant layer disposed on one side of the functional layer; wherein, the brightness value of the first side of the first antioxidant layer away from the functional layer is less than or equal to 60, and the color difference on the first side is less than or equal to 1. By coating an antioxidant layer on the outermost layer of the copper foil and defining the brightness value and color difference △E of the overall copper foil surface, the surface color of the copper foil becomes gray and uniform as a whole, thereby covering the unevenness of other colors and improving the uniformity of the copper foil surface color and the finished product quality. In summary, the present invention solves the problem that when the copper foil is subjected to roll electroplating, due to process differences, different roughening stripe patterns are generated on the copper foil surface, making the appearance of the copper foil uneven and affecting the finished product quality.

[0023] It should be understood that the content described in this part is not intended to identify the key or important features of the embodiments of the present invention, nor is it used to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0025] Figure 1 is a schematic structural diagram of a metal foil according to an embodiment of the present invention;

[0026] Figure 2 is a schematic structural diagram of another metal foil according to an embodiment of the present invention;

[0027] Figure 3 It is a schematic structural diagram of another metal foil provided according to an embodiment of the present invention. Detailed implementation manners

[0028] In order to enable those skilled in the art to better understand the solution of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0029] It should be noted that the terms "first", "second", etc. in the description and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that such used data can be interchanged under appropriate circumstances so that the embodiments of the present invention described here can be implemented in an order different from those illustrated or described here. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device that includes a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0030] Figure 1 It is a schematic structural diagram of a metal foil provided according to an embodiment of the present invention. Refer to Figure 1 , an embodiment of the present invention provides a metal foil, which includes:

[0031] Function layer 10;

[0032] The first antioxidant layer 20 disposed on one side of the function layer 10;

[0033] Wherein, the brightness value of the first side of the first antioxidant layer 20 away from the function layer 10 is less than or equal to 60, and the color difference on the first side is less than or equal to 1.

[0034] Specifically, the functional layer 10 is mainly used for circuit production. The material of the functional layer 10 can be any one of aluminum, titanium, zinc, iron, nickel, chromium, cobalt, copper, silver, and gold. The first antioxidant layer 20 is located on the surface of the functional layer 10, and the thickness of the functional layer 10 is between 1.5 μm and 35 μm. In this embodiment, the first antioxidant layer 20 coated on the outermost layer of the copper foil achieves the above-mentioned brightness value (L value) and color difference ΔE range by changing the component ratio. For example, when the functional layer 10 is a copper foil, when the brightness value of the first side of the first antioxidant layer 20 away from the functional layer 10 is less than or equal to 60, and the color difference on the first side is less than or equal to 1, the surface color of the copper foil becomes gray and uniform as a whole, thereby covering the unevenness of other colors and improving the uniformity of the surface color of the copper foil.

[0035] The Lab values are three basic parameters used to quantify colors in a color space. The Lab values consist of three dimensions: L (brightness): ranging from 0 to 100, representing the degree of light and dark from pure black (0) to pure white (100). For example, L = 50 represents medium gray. a (red-green chromaticity): ranging from -128 to +128 (or -120 to +120, with slight differences in different standards), positive values indicating a red tendency and negative values indicating a green tendency. For example, a = +50 is an obvious red tone, and a = -30 is a light green tone. b (yellow-blue chromaticity): having the same range as the a value, positive values indicating a yellow tendency and negative values indicating a blue tendency. For example, b = +40 is a yellow tone, and b = -20 is a blue tone. The Lab values are mainly used to quantify color differences. And the color difference ΔE in this embodiment is obtained by calculating the Lab values of two sampled points on the same plane. The color difference ΔE represents color balance. For example: ΔE < 1: imperceptible to the human eye. ΔE > 5: significant color difference, regarded as two different colors.

[0036] The operation formula for the color difference ΔE is as follows:

[0037]

[0038] Among them, ΔL* represents the difference in lightness (L* value) between two colors. Δa* represents the difference in red / green value (a* value) between two colors, positive values indicating a red bias and negative values indicating a green bias. Δb* represents the difference in yellow / blue value (b* value) between two colors, positive values indicating a yellow bias and negative values indicating a blue bias.

[0039] The L*, a*, and b* values are obtained by measuring the three stimulus values X, Y, Z of the color and according to specific transformation formulas. These values reflect the position of the color in the Lab color space, where L represents brightness or lightness, and a and b represent chromaticity or hue. In practical applications, the L*, a*, and b* values of the standard color and the sample color can be measured and then substituted into the above formula to calculate the color difference ΔE between them. The larger the value of ΔE, the greater the difference between the two colors.

[0040] The technical solution of the embodiment of the present invention provides a metal foil, which includes: a functional layer; a first antioxidant layer disposed on one side of the functional layer; wherein, the brightness value of the first side of the first antioxidant layer away from the functional layer is less than or equal to 60, and the color difference on the first side is less than or equal to 1. After coating the antioxidant layer on the outermost layer of the copper foil, the brightness value and the color difference △E of the overall copper foil surface are defined, making the surface color of the copper foil turn gray and uniform as a whole, thereby covering the unevenness of other colors and improving the uniformity of the copper foil surface color and the finished product quality. In summary, the present invention solves the problem that when the copper foil is subjected to roll electroplating, due to process differences, different roughening stripe patterns are generated on the copper foil surface, making the appearance of the copper foil uneven and affecting the finished product quality.

[0041] Continue to refer to Figure 1 , optionally, the material of the first antioxidant layer 20 includes: Zn and Ni;

[0042] The mass fraction ratio of Zn and Ni is 1:1 to 1:10.

[0043] Optionally, the content of Ni is 1mg / m 2 ~100mg / m 2 .

[0044] Specifically, in the copper foil industry, electroplating a ZnNi alloy coating is commonly used for antioxidant treatment. The higher the Ni content in the first antioxidant layer 20, the darker the overall color, which is beneficial to covering the stripe color difference or mottled watermark during production. However, it cannot be too dark. If there is too much Ni or the ratio is too high in the first antioxidant layer 20, it is easy to cause etching residue and short circuit of the circuit when making the circuit. And when the Ni content is too low, the color is too light and there is no covering power. Once the Ni ratio in the first antioxidant layer 20 is too low, it is easy to occur side etching when making the circuit, and the circuit is easy to fall off, affecting the reliability of the circuit board.

[0045] In the first antioxidant layer coated on the copper foil in this embodiment, by changing the component ratio to achieve the above L value and color difference △E range, the antioxidant layer is composed of Zn and Ni, where the ratio of Zn to Ni is 1:1 to 1:10, and the total Ni content is 1mg / m 2 ~100mg / m 2 When it is, it is beneficial to cover the stripe color difference or mottled watermark during production. When making the circuit, it can avoid etching residue and short circuit of the circuit. It can also avoid side etching when making the circuit, and the circuit is not easy to fall off, thereby improving the reliability of the circuit board.

[0046] Optionally, the mass fraction ratio of Zn and Ni is 1:2 to 1:3.

[0047] Specifically, the ZnNi content in the first antioxidant layer affects the bonding strength with pp. When the Ni content is relatively high, the copper foil has better high-temperature resistance, and the copper foil and the resin are less likely to delaminate during soldering. The best effect is achieved when the ZnNi ratio is between 1:2 and 1:3.

[0048] The process for fabricating the first antioxidant layer is as follows: after fabricating the functional layer using raw foil or other electroplating methods, the first antioxidant layer is electroplated onto the surface of the functional layer, and the ZnNi content and ratio of the first antioxidant layer are adjusted by setting parameters such as the plating solution formula and electroplating current during electroplating.

[0049] Figure 2 is a schematic structural diagram of another metal foil provided according to an embodiment of the present invention. Refer to Figure 2 , optionally, the metal foil further includes: a carrier layer 30;

[0050] The carrier layer 30 is disposed on the side of the functional layer 10 away from the first antioxidant layer 20.

[0051] Specifically, the carrier layer 30 can be formed by means of electrochemical deposition, vacuum sputtering + electroplating, vacuum sputtering, etc. The material of the carrier layer 30 can be any one of aluminum, titanium, zinc, iron, nickel, chromium, cobalt, copper, silver, and gold.

[0052] Since the carrier layer 30 mainly serves as a carrier, a certain thickness is required. The thickness of the carrier layer 30 affects the bonding force between the functional layer 10 and the circuit board, and also affects the overall thickness of the peelable metal foil. The thickness of the carrier layer 30 can be 10 μm to 100 μm. By limiting the thickness of the carrier layer 30 within the above thickness range, the carrier layer 30 is not too thin, ensuring that its thickness is sufficient to provide support strength for the peelable metal foil as a carrier layer, and facilitating the production and manufacturing of the carrier layer 30, because a too thin carrier layer 30 is prone to adhering to the surface of the conveying roller, resulting in defects such as wrinkles and fine lines. At the same time, it is not too thick, avoiding excessive volume and weight of the peelable metal foil.

[0053] Continuing to refer to Figure 2 , optionally, the metal foil further includes: a release layer 40;

[0054] The release layer 40 is disposed between the carrier layer 30 and the functional layer 10.

[0055] Specifically, the release layer 40 is processed onto the carrier layer 30 by any one of electroplating process, vacuum sputtering process, and coating process. In application, the side of the first oxide layer 20 on the outermost layer of the metal foil is pressed onto a carrier such as a circuit board substrate. After the pressing process is completed, the carrier layer 30 on the other side of the metal foil is peeled off through the release layer 40, and then circuits are formed on the circuit board substrate by means of copper plating, masking, etching, etc.

[0056] The material of the release layer 40 can be an organic release layer, such as nitrogen-containing compounds, sulfur-containing compounds, carboxylic acids, etc., or an inorganic release layer, including a metal base layer or an alloy layer. It can also be an inorganic layer and an organic layer together as the release layer 40, for example, a mixture of metal oxides and organic substances is used.

[0057] The function of the release layer 40 is to separate the carrier layer 30 from the functional layer 10 through peeling; at the same time, due to the presence of the release layer 40, metal migration between the functional layer 10 and the carrier layer 30 can be blocked.

[0058] Figure 3 It is a schematic structural diagram of another metal foil provided according to an embodiment of the present invention. Refer to Figure 3 , optionally, the metal foil further includes: a second antioxidant layer 50;

[0059] The second antioxidant layer 50 is disposed on the side of the functional layer 10 away from the first antioxidant layer 20.

[0060] Continue to refer to Figure 3 , optionally, the material of the second antioxidant layer 50 includes: Zn and Ni;

[0061] The mass fraction ratio of Zn and Ni is 1:1 to 1:10.

[0062] Specifically, in the copper foil industry, antioxidant treatment generally uses electroplated ZnNi alloy coatings. The higher the Ni content in the second antioxidant layer 50, the darker the overall color, which is beneficial to covering the stripe color difference or mottled watermarks during production. However, it cannot be too dark. If there is too much Ni or the ratio is too high in the second antioxidant layer 50, it is easy to cause etching residue and short circuit of the circuit during circuit production. And when the Ni content is too low, the color is too light and there is no covering power. Once the ratio of Zn to Ni in the second antioxidant layer 50 is too low, it is easy to occur side etching during circuit production, and the circuit is easy to fall off, affecting the reliability of the circuit board.

[0063] In the second antioxidant layer 50 coated on the copper foil in this embodiment, by changing the component ratio to achieve the above L value and color difference △E range, the second antioxidant layer is composed of Zn and Ni. Among them, the ratio of Zn to Ni is 1:1 to 1:10, and the total Ni content is 1mg / m 2 ~100mg / m 2 , which is beneficial to covering the stripe color difference or mottled watermarks during production, and avoiding etching residue and short circuit of the circuit during circuit production. It can also prevent side etching during circuit production and the circuit is not easy to fall off, thereby improving the reliability of the circuit board.

[0064] Optionally, the mass fraction ratio of Zn and Ni is 1:2 to 1:3.

[0065] Specifically, the ZnNi content in the second antioxidant layer affects the bonding strength with pp. When the Ni content is relatively high, the copper foil has better high-temperature resistance, and the copper foil and the resin are less likely to delaminate during soldering. The best effect is achieved when the ZnNi ratio is between 1:2 and 1:3.

[0066] The process for manufacturing the second antioxidant layer is as follows: after making the functional layer using raw foil or other electroplating methods, the second antioxidant layer is electroplated on the surface of the functional layer, and the ZnNi content and ratio of the second antioxidant layer are adjusted by setting the plating solution formula and electroplating current parameters during electroplating.

[0067] Example 1

[0068] A metal foil includes a functional layer and a first antioxidant layer. The brightness value of the first side of the first antioxidant layer away from the functional layer is 35, and the color difference on the first side is 0.6. The material of the functional layer is Cu, and the material of the first antioxidant layer is composed of Zn and Ni. The ratio of Zn to Ni is 1:8, and the total Ni content is 80 mg / m 2 。

[0069] Example 2

[0070] Different from Example 1, the brightness value of the first side of the first antioxidant layer away from the functional layer is 45, and the color difference on the first side is 0.8. The material of the first antioxidant layer is composed of Zn and Ni. The ratio of Zn to Ni is 1:6, and the total Ni content is 60 mg / m 2 。

[0071] Example 3

[0072] Different from Example 1, the brightness value of the first side of the first antioxidant layer away from the functional layer is 55, and the color difference on the first side is 0.9. The metal foil further includes a second antioxidant layer, which is disposed on the side of the functional layer away from the first antioxidant layer. The material of the second antioxidant layer is composed of Zn and Ni. Among them, the ratio of Zn to Ni is 1:4, and the total Ni content is 40 mg / m 2 。

[0073] Comparative Example 1

[0074] The metal foil includes a functional layer and a first antioxidant layer. The brightness value of the first side of the first antioxidant layer away from the functional layer is 65, and the color difference on the first side is 1.2. The material of the functional layer is Cu, and the material of the first antioxidant layer is composed of Zn and Ni. The ratio of Zn to Ni is 2:1, and the total Ni content is 0.5 mg / m 2 。

[0075] Comparative Example 2

[0076] Different from Comparative Example 1, the brightness value of the first side of the first antioxidant layer away from the functional layer is 70, and the color difference on the first side is 1.3. The material of the first antioxidant layer is composed of Zn and Ni, and the ratio of Zn to Ni is 4:1. The total content of Ni is 0.2mg / m 2 .

[0077] According to the test comparison and analysis, it can be seen that the surface color of the metal foil in Examples 1-3 becomes gray and uniform as a whole, thereby covering the unevenness of other colors and improving the uniformity of the surface color of the copper foil and the finished product quality. In the two comparative examples, the surface color of the metal foil is lighter, and there are stripe mottles on the surface of the copper foil, and the appearance of the copper foil is uneven, affecting the quality of the finished product.

[0078] An embodiment of the present invention also provides a metal-clad laminate, and the metal-clad laminate includes the metal foil of any embodiment of the present invention.

[0079] Since the metal-clad laminate includes the metal foil provided by any embodiment of the present invention, therefore, the above-mentioned metal-clad laminate has the same beneficial effects as the metal foil, and will not be repeated here.

[0080] The above specific embodiments do not constitute a limitation to the protection scope of the present invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A metal foil, characterized in that, Comprising: Functional layer; A first antioxidant layer disposed on one side of the functional layer; Wherein, the brightness value of the first side of the first antioxidant layer away from the functional layer is less than or equal to 60, and the color difference on the first side is less than or equal to 1.

2. The metal foil according to claim 1, wherein The material of the first antioxidant layer comprises: Zn and Ni; The mass fraction ratio of Zn and Ni is 1:1 to 1:

10.

3. The metal foil according to claim 2, characterized in that, The mass fraction ratio of Zn and Ni is 1:2 to 1:

3.

4. The metal foil according to claim 2, characterized in that, The content of Ni is 1 mg / m 2 ~100 mg / m 2 .

5. The metal foil according to any one of claims 1-4, characterized in that Further comprising: Carrier layer; The carrier layer is disposed on the side of the functional layer away from the first antioxidant layer.

6. The metal foil according to claim 5, wherein Further comprising: Release layer; The release layer is disposed between the carrier layer and the functional layer.

7. The metal foil according to any one of claims 1-4, characterized in that, Further comprising: Second antioxidant layer; The second antioxidant layer is disposed on the side of the functional layer away from the first antioxidant layer.

8. The metal foil according to claim 7, characterized in that, The material of the second antioxidant layer comprises: Zn and Ni; The mass fraction ratio of Zn and Ni is 1:1 to 1:

10.

9. The metal foil according to claim 8, characterized in that, The mass fraction ratio of Zn and Ni is 1:2 to 1:

3.

10. A metal-clad laminate, characterized in that, The metal-clad laminate comprises the metal foil according to any one of claims 1-9.

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