Composite metal foil and cable material

Abstract

The invention relates to the technical field of cables, in particular to a composite metal foil and a cable material. The composite metal foil comprises a base material layer and a shielding layer which are laminated, wherein the intrinsic viscosity eta of the material of the base material layer is 0.53 dl / g to 0.68 dl / g; the composite metal foil containing the base material layer material with specific intrinsic viscosity can have good elongation and tinning efficiency during welding.

Description

Technical Field

[0001] The present invention relates to the technical field of cables, and in particular to a composite metal foil and cable material. Background Art

[0002] The main function of the shielding layer of wires and cables is to reduce the impact of external electromagnetic interference on the signal and improve the cable's anti-interference ability.

[0003] Compared with aluminum foil, copper foil has better shielding effect and service life. According to the different copper foil structures, copper foil shielding layers can be divided into the following types: 1. Copper braided shielding layer, woven from fine copper wire, with good flexibility and tensile resistance, wrapped on the outside of the insulation layer, and can be bent repeatedly; 2. Copper mesh braided shielding layer, the denser copper mesh braiding structure can shield high-frequency signals, and is often used in high-demand radio frequency cables and high-speed data transmission cables; 3. Aluminum-copper double-layer shielding layer, combining aluminum foil and copper mesh braided double-layer shielding structure, can effectively shield low-frequency and high-frequency interference, and achieve a balance between strength and flexibility; 4. Composite copper foil shielding layer, whose structure includes copper layer and composite film material, can provide excellent shielding performance in the visible light band, near-infrared band and microwave band, while also reducing the amount of copper, making the overall weight lighter and having a wider range of application scenarios.

[0004] However, the current composite copper foil has the following problems when used for cable shielding: the composite copper foil is wrapped around the cable in a winding manner, and the end is welded to the cable when the cable joint is made. At this time, the composite film material needs to be melted and then contacted with copper to form welding. The composite film material in the existing composite copper foil shielding layer is often made of PET material. If a thinner material is used, it can achieve an easy melting effect, but the elongation is low, and it is easy to break when wrapped around the cable, resulting in the failure of the shielding effect; if a thicker PET is used, although a larger elongation can be guaranteed and no breakage will occur, the tin cannot be combined with the copper during welding, and the tinning effect is poor. Summary of the invention

[0005] Therefore, the technical problem to be solved by the present invention is to overcome the problem that it is difficult to take into account both shielding effect and production quality when the existing composite copper foil is used for cable shielding, thereby providing a composite metal foil and cable material.

[0006] A first aspect of the present invention protects a composite metal foil, wherein the composite metal foil comprises a stacked substrate layer and a shielding layer, and the characteristic viscosity η of the material of the substrate layer is 0.53 dl / g to 0.68 dl / g.

[0007] In the present invention, the intrinsic viscosity is detected in a conventional manner.

[0008] According to the present invention, the crystallinity of the material of the substrate layer is 0 to 30%.

[0009] In the present invention, the crystallinity of the substrate layer material can be detected by differential scanning calorimetry, X-ray diffraction, density method, infrared spectroscopy, nuclear magnetic resonance, optical microscopy and polarizing microscopy. In the present invention, X-ray diffraction is used for detection.

[0010] According to the present invention, after the material of the substrate layer is tinned at 250° C. to 300° C. for 2 to 5 seconds, the melting area of ​​the substrate layer is greater than 30%.

[0011] In the present invention, a visual software processing statistical method is used to detect the melting area of ​​the material of the substrate layer after tinning.

[0012] According to the present invention, the melting area of ​​the material of the substrate layer after tin immersion at 270° C. for 3 seconds is greater than 70%.

[0013] According to the present invention, the ratio of the thickness of the substrate layer to the thickness of the shielding layer is 2 to 20:1.

[0014] According to the present invention, the ratio of the elongation of the composite metal foil to the elongation of the substrate layer is 0.05 to 0.7:1.

[0015] In the present invention, a tensile testing machine is used to detect the elongation, and the specific calculation formula of the elongation is: (length of the sample when it breaks-initial length of the sample) / initial length of the sample×100%.

[0016] According to the present invention, the thickness of the substrate layer is 4 μm to 8 μm.

[0017] In the present invention, the thickness of each layer is detected by electron microscope observation and software processing.

[0018] According to the present invention, the thickness of the shielding layer is 0.5 μm to 4 μm.

[0019] In the present invention, the material of the substrate layer includes at least one of PET, PP, PI, PVC, PE, EVA, and PC; the material of the shielding layer includes at least one of copper, aluminum, gold, silver, iron, nickel, chromium, and zinc.

[0020] In the present invention, the PET can be purchased from a commercial source or synthesized, and the weight average molecular weight of the PET is 30000-70000 g / mol.

[0021] According to the present invention, the composite metal foil further includes an adjustment layer, and the adjustment layer is arranged between the shielding layer and the substrate layer.

[0022] According to the present invention, the material of the adjustment layer includes a metal seed layer or a polymer glue.

[0023] According to the present invention, the thickness of the adjustment layer is 2 nm to 2 μm.

[0024] According to the present invention, the adjustment layer is a metal seed layer, wherein the material of the metal seed layer is a conductive metal. By forming the seed layer on a non-metallic substrate layer, the substrate layer can be made conductive, so that a shielding layer can be formed on the seed layer by electroplating.

[0025] Alternatively, the adjustment layer is a polymer adhesive, and the adhesive layer material includes at least one of polyurethane, water-soluble epoxy resin, acrylic acid, polyamide, and phenolic resin. The function of the adjustment layer is to enhance the bonding strength between the substrate layer and the shielding layer to avoid stratification during use. When a polymer adhesive is selected, a pressing method is generally used to form the shielding layer.

[0026] In the present invention, the preparation method of the composite metal foil is a conventional preparation method in the art, and a shielding layer is prepared on the substrate layer by at least one method selected from lamination, electroplating, chemical plating, and vacuum sputtering; typically, but not limitingly, a copper metal seed layer with a thickness of 5 nm to 500 nm is vacuum sputtered on the surface of the PET layer, and then a copper layer is electroplated on the copper metal seed layer, and the thickness of the copper layer is 0.5 μm to 4 μm.

[0027] A second aspect of the present invention protects a cable material, wherein the cable material comprises a cable body and the aforementioned composite metal foil.

[0028] The technical solution of the present invention has the following advantages:

[0029] 1. The present invention provides a composite metal foil, wherein the composite metal foil comprises a stacked substrate layer and a shielding layer, the characteristic viscosity η of the material of the substrate layer is 0.53dl / g to 0.68dl / g; the composite metal foil comprising a substrate layer material with a specific characteristic viscosity is used for cable shielding, has good elongation and tinning efficiency during welding, ensures welding stability with the joint, and does not cause delamination and rupture, thereby improving the working reliability of the cable.

[0030] 2. The specific crystallinity of the substrate layer material in the present invention can improve the toughness of the substrate layer, make the substrate layer have better solubility, and reduce the internal stress of the substrate layer, which is beneficial to reduce the probability of the metal foil of the composite machine breaking during use, and further improve the processing efficiency of the cable shielding material and the working reliability of the cable.

[0031] 3. The specific thickness ratio of the substrate layer to the shielding layer of the present invention can ensure the shielding effect while further reducing the overall amount of the metal shielding layer, thereby improving the structural stability while reducing the overall weight and production cost.

[0032] 4. The ratio of the elongation of the composite metal foil of the present invention to the elongation of the substrate layer can further improve the overall physical properties of the composite metal foil and avoid the breakage of the cable shielding material during winding.

[0033] 5. The specific thickness of the substrate layer of the present invention can further reduce the amount of shielding layer material used, improve the overall toughness of the material, avoid fracture, and reduce costs.

[0034] 6. The specific thickness of the shielding layer of the present invention can further ensure the performance of shielding effect and elongation at the same time, meeting the use scenarios of cable shielding.

[0035] 7. The specific thickness of the adjustment layer of the present invention can further enhance the bonding strength, balance the use requirements of shielding effect and elongation, and meet the use scenarios of cable shielding. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0037] Figure 1 is a schematic structural diagram of the composite metal foil of Example 1;

[0038] Reference numerals: 1 - shielding layer; 2 - adjustment layer; 3 - substrate layer. DETAILED DESCRIPTION

[0039] The following examples are provided for a better understanding of the present invention, but are not intended to limit the best mode of implementation, nor to limit the content and protection scope of the present invention. Any product identical or similar to the present invention obtained by anyone under the inspiration of the present invention or by combining the features of the present invention with other prior arts shall fall within the protection scope of the present invention.

[0040] If no specific experimental steps or conditions are specified in the examples, the conventional experimental steps or conditions described in the literature in the field can be used. If no manufacturer is specified for the reagents or instruments used, they are all conventional reagent products that can be obtained commercially.

[0041] The crystallinity of the substrate layer material is detected by X-ray diffraction method;

[0042] The melting area of ​​the substrate layer after tinning is detected by using visual software processing statistics. The specific method is: taking a photo sampling method to obtain an image of the outer side of the substrate layer after tinning, analyzing the obtained image through image processing software or program, and counting the area of ​​the tinned area (silver metal area) as the ratio of the melting area of ​​the substrate layer;

[0043] The thickness of each layer is detected by electron microscope observation and software processing;

[0044] The elongation at break was tested using a tensile testing machine according to the tensile testing method. The specific calculation formula for the elongation was: (total length at break - initial length) / initial length × 100%.

[0045] The weight average molecular weight of PET is 50,000 g / mol.

[0046] Example 1

[0047] This embodiment provides a composite metal foil, which is as follows:

[0048] A copper seed adjustment layer is formed on one side of a PET substrate layer by magnetron sputtering, and then a copper shielding layer is formed by electroplating thickening to obtain a composite metal foil.

[0049] The intrinsic viscosity η of the substrate layer material of PET material is 0.61 dl / g, the crystallinity is 30%, the thickness of the substrate layer is 6 μm, the thickness of the adjustment layer is 5 nm, and the thickness of the shielding layer is 1.1 μm; the ratio of the overall elongation of the composite metal foil to the elongation of the substrate layer is 0.37:1;

[0050] Under the conditions of 270°C and 3s, the composite metal foil was subjected to a tinning experiment, and the melting area of ​​the substrate layer was 62%; the overall elongation of the composite metal foil was 32.7%; the structural schematic diagram of Example 1 is shown in Figure 1 As shown, the stacked substrate layer, the regulating layer and the shielding layer can be seen.

[0051] Example 2

[0052] This embodiment provides a composite metal foil, which is as follows:

[0053] A copper seed adjustment layer is formed on one side of a PET substrate layer by magnetron sputtering, and then a copper shielding layer is formed by electroplating thickening to obtain a composite metal foil.

[0054] The intrinsic viscosity η of the PET substrate layer material is 0.68 dl / g, the crystallinity is 24%, the thickness of the substrate layer is 8 μm, the thickness of the adjustment layer is 200 nm, and the thickness of the shielding layer is 1.5 μm; the ratio of the elongation of the composite metal foil to the elongation of the substrate layer is 0.51:1;

[0055] Under the conditions of 270°C and 3s, the composite metal foil was subjected to a tin immersion experiment, and the melting area of ​​the substrate layer was 85%; the overall elongation of the composite metal foil was 34.4%.

[0056] Example 3

[0057] This embodiment provides a composite metal foil, which is as follows:

[0058] This embodiment adopts the same stacking structure as that of the embodiment 1, wherein, unlike the embodiment 1, the crystallinity of the PET substrate layer is 0; the ratio of the elongation of the composite metal foil as a whole to the elongation of the substrate layer is 0.24:1, and the elongation is 59.6%;

[0059] Under the conditions of 270°C and 3s, the composite metal foil was subjected to a tin immersion experiment, and the melting area of ​​the substrate layer was 91%; the overall elongation of the composite metal foil was 35.9%.

[0060] Example 4

[0061] This embodiment provides a composite metal foil, which is as follows:

[0062] This embodiment adopts the same stacking structure as that of the embodiment 1, wherein the difference from the embodiment 1 is that the thickness of the substrate layer is 6.5 μm, the thickness of the adjustment layer is 5 nm, and the thickness of the shielding layer is 0.8 μm;

[0063] Under the conditions of 270°C and 3s, the composite metal foil was subjected to a tin immersion experiment, and the melting area of ​​the substrate layer was 73%; the overall elongation of the composite metal foil was 28.7%.

[0064] Example 5

[0065] This embodiment provides a composite metal foil, which is as follows:

[0066] An epoxy resin adjustment layer is coated on a PET substrate layer by a coating method, and a copper material shielding layer is pressed on the adjustment layer to obtain a composite metal foil; wherein the thickness of the substrate layer is 4.5 μm, the thickness of the adjustment layer is 1.5 μm, and the thickness of the shielding layer is 1 μm;

[0067] Under the conditions of 270°C and 3s, the composite metal foil was subjected to a tin immersion experiment, and the melting area of ​​the substrate layer was 84%; the overall elongation of the composite metal foil was 24.4%.

[0068] Example 6

[0069] This embodiment provides a composite metal foil, which is as follows:

[0070] This embodiment adopts the same stacking structure as that of the embodiment 1, wherein the difference from the embodiment 1 is that the thickness of the shielding layer is 2 μm;

[0071] Under the conditions of 270°C and 3s, the composite metal foil was subjected to a tin immersion experiment, and the melting area of ​​the substrate layer was 83%; the overall elongation of the composite metal foil was 19.8%.

[0072] Comparative Example 1

[0073] This comparative example provides a composite metal foil, which is as follows:

[0074] The same stacking structure as in Example 1 is adopted, wherein the difference from Example 1 is that the intrinsic viscosity η of the substrate layer material of PET material is 0.51 dl / g and the crystallinity is 35%;

[0075] Under the conditions of 270°C and 3s, the composite metal foil was subjected to a tinning experiment, and the melting area of ​​the substrate layer was 48.6%; the overall elongation of the composite metal foil was 23.1%. Although the comparative example has a higher elongation, the melting area of ​​the substrate layer is too low and still cannot meet the welding requirements with the cable joint.

[0076] Comparative Example 2

[0077] This comparative example provides a composite metal foil, which is as follows:

[0078] The same stacking structure as in Example 1 is adopted, wherein the difference from Example 1 is that the characteristic viscosity η of the substrate layer material made of PET is 0.70 dl / g.

[0079] Under the conditions of 270°C and 3s, a tin immersion experiment was carried out on the composite metal foil, and the melting area of ​​the substrate layer was 27.9%; the overall elongation of the composite metal foil was 18.5%.

[0080] In the present invention, it can be seen from the specific data that the embodiments and comparative examples have excellent elongation and tin melting area, can ensure the welding stability with the joint, and at the same time do not cause delamination and cracking, thereby improving the working reliability of the cable.

[0081] It can be seen from Example 1 and Comparative Examples 1 and 2 that the substrate layer material with a specific intrinsic viscosity can further improve the tinning efficiency and elongation.

[0082] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived from these are still within the scope of protection of the invention.

Claims

1. A composite metal foil, characterized in that: The composite metal foil comprises a laminated substrate layer and a shielding layer, and the intrinsic viscosity η of the material of the substrate layer is 0.53 dl / g to 0.68 dl / g.

2. The composite metal foil according to claim 1, characterized in that The material of the substrate layer has a crystallinity of 0 to 30%.

3. The composite metal foil according to any one of claims 1 to 2, characterized in that After the material of the substrate layer is immersed in tin at 250° C. to 300° C. for 2 to 5 seconds, the melting area of ​​the substrate layer is greater than 30%.

4. The composite metal foil according to claim 3, characterized in that: After the material of the substrate layer is immersed in tin at 270° C. for 3 seconds, the melting area of ​​the substrate layer is greater than 70%.

5. The composite metal foil according to claim 1, characterized in that: The ratio of the thickness of the substrate layer to the thickness of the shielding layer is 2 to 20:

1.

6. The composite metal foil according to claim 5, characterized in that: The ratio of the elongation of the composite metal foil to the elongation of the substrate layer is 0.05 to 0.7:

1.

7. The composite metal foil according to claim 5, characterized in that: The thickness of the substrate layer is 4 μm to 8 μm; And / or, the shielding layer has a thickness of 0.5 μm to 4 μm.

8. The composite metal foil according to claim 5, characterized in that: The composite metal foil further includes an adjustment layer, and the adjustment layer is arranged between the shielding layer and the substrate layer.

9. The composite metal foil according to claim 8, characterized in that: The thickness of the adjustment layer is 2 nm to 2 μm.

10. A cable material, characterized in that: The cable material comprises a cable body and the composite metal foil according to any one of claims 1 to 9.

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