Manufacturing method for improving tensile strength of PTFE high-frequency and high-speed flexible copper-clad laminate substrate

Abstract

The present invention provides a method for improving the tensile strength of a PTFE high-frequency, high-speed, flexible copper-clad laminate substrate, which belongs to the field of copper-clad laminate processing technology. It solves the problem that some existing flexible copper-clad laminates have low tensile strength and poor heat dissipation performance. The method for improving the tensile strength of a PTFE high-frequency, high-speed, flexible copper-clad laminate substrate comprises the following steps: taking a polytetrafluoroethylene material and subjecting it to radiation cross-linking treatment to obtain cross-linked polytetrafluoroethylene, i.e., a cross-linked polytetrafluoroethylene substrate. The copper-clad laminate substrate produced by the present invention improves its own strength and tensile properties through a first reinforcing resin and a second reinforcing resin. When facing external force or impact, it uses flexible materials and buffer materials to reduce shock, reduce damage caused by external force or impact, and makes it less likely to break. Moreover, the surrounding metal frame can greatly improve the tensile strength of the copper-clad laminate substrate. At the same time, the heat dissipation performance of the copper-clad laminate substrate is better, and it can evenly conduct heat, effectively preventing heat from being concentrated in one place.

Description

Technical Field

[0001] The invention belongs to the technical field of copper clad laminate processing and relates to a manufacturing method, in particular to a manufacturing method for improving the tensile strength of a PTFE high-frequency and high-speed flexible copper clad laminate substrate. Background Art

[0002] Copper-clad laminate (CCL), short for copper-clad laminate, is the fundamental material for printed circuit boards (PCBs). It's made by impregnating a reinforcing material with resin, coating one or both sides with copper foil, and then heat-pressing. When used in multi-layer PCBs, CCL, also known as the core board, performs the three main functions of conducting electricity, insulating, and supporting the PCB. The performance of CCL significantly impacts the performance, quality, machinability, and manufacturing cost of the PCB, making it the foundation of the electronics industry.

[0003] After searching, it was found that Chinese patent documents disclosed a high-frequency and high-speed flexible copper clad laminate and its preparation method [Application number: CN201710344223.3; Publication number: CN107175860B]. This high-frequency and high-speed flexible copper clad laminate and its preparation method, the flexible copper clad laminate consists of three layers: a polymer insulating base film, a polymer adhesive layer and a metal foil, and has good dielectric properties. Among them, the dielectric constant of the prepared flexible copper clad laminate is 2.3-2.9, and the dielectric loss is 0.001-0.005. The preparation method is to first irradiate the polymer to prepare an insulating base film, and then evenly apply a curable resin adhesive on the irradiated polymer insulating base film, followed by continuous pressing with the metal foil with a hot roller, and finally high-temperature curing to obtain a high-frequency and high-speed flexible copper clad laminate.

[0004] The patent discloses that the flexible copper clad laminate has the characteristics of high frequency and high speed, and has extremely low dielectric constant and dielectric loss. It can be widely used in radar, aerospace equipment, navigation equipment, aircraft instruments, smart phones and other fields. However, the flexible copper clad laminate has poor strength and poor tensile properties. When faced with external force or impact, it is easy to cause the flexible copper clad laminate itself to break or damage, resulting in circuit damage. In addition, the flexible copper clad laminate has poor thermal conductivity. During use, heat cannot be evenly transferred and dissipated. The heat is concentrated on the circuit and cannot be dissipated, causing the local temperature of the flexible copper clad laminate to rise, which can easily cause a short circuit. Summary of the Invention

[0005] The purpose of the present invention is to address the above-mentioned problems in the existing technology and propose a manufacturing method for improving the tensile strength of a PTFE high-frequency, high-speed, flexible copper-clad laminate substrate. The copper-clad laminate substrate manufactured by the manufacturing method for improving the tensile strength of the PTFE high-frequency, high-speed, flexible copper-clad laminate substrate has better strength and tensile properties. When facing external force or impact, it can reduce the damage caused by the external force or impact, making it less likely to break. In addition, the surrounding metal frame can significantly improve the tensile strength of the copper-clad laminate substrate. At the same time, the copper-clad laminate substrate has better heat dissipation performance, can evenly conduct heat, and effectively prevent heat from being concentrated in one place, thereby solving the problems of some existing flexible copper-clad laminates having low tensile strength and poor heat dissipation performance.

[0006] The purpose of the present invention can be achieved through the following technical solutions:

[0007] A method for improving the tensile strength of a PTFE high-frequency, high-speed, flexible copper-clad laminate substrate comprises the following steps:

[0008] S1. A polytetrafluoroethylene material is subjected to radiation cross-linking treatment to obtain cross-linked polytetrafluoroethylene, i.e., a cross-linked polytetrafluoroethylene substrate. A fifth thermally conductive adhesive film is uniformly coated on the surface of the cross-linked polytetrafluoroethylene substrate using a coating machine at a speed of 40-80 r / min and a temperature of 100-135° C. A buffer material is then coated on the surface of the fifth thermally conductive adhesive film. A fourth thermally conductive adhesive film is then coated on the surface of the buffer material. A second reinforcing resin is then coated on the third thermally conductive adhesive film to obtain a copper clad laminate substrate A.

[0009] S2. Using a coating machine at a speed of 40-90 r / min and a temperature of 100-135° C., uniformly coat the second thermally conductive adhesive film on top of the copper clad laminate substrate A. Then, connect the flexible material coated with the first thermally conductive adhesive film on top of the second thermally conductive adhesive film. Finally, connect the roughened copper foil to the first thermally conductive adhesive film to obtain the copper clad laminate substrate B.

[0010] S3, hot pressing the copper clad laminate substrate B obtained in step S2 with a roller hot press to obtain a copper clad laminate substrate C, wherein the hot press temperature is controlled within the range of 100-180° C., and then placing the copper clad laminate substrate C in a drying oven for curing treatment for 5-12 hours to obtain a high-frequency, high-speed, flexible copper clad laminate substrate;

[0011] S4. After flanging the metal strip, an insulating coating is sprayed on the metal strip using an electrostatic spraying process. The metal strip is then cut and bent, and then coated on the surface of a high-frequency, high-speed, flexible copper-clad laminate substrate. During the coating process, a two-component epoxy resin sealing insulating glue is applied between the metal strip and the substrate to connect the metal strip to the substrate.

[0012] S5. Welding the cut points of the metal strip together through a welding process, so that the metal frame is coated on the high-frequency and high-speed flexible copper-clad laminate substrate, thereby obtaining a high-frequency and high-speed flexible copper-clad laminate substrate with higher tensile strength.

[0013] In step S1, the specific steps of the radiation cross-linking treatment of the polytetrafluoroethylene material are:

[0014] S1.1. Place polytetrafluoroethylene into a high-temperature radiation box, seal the box, and then introduce protective gas into the box;

[0015] S1.2. Control the temperature inside the high-temperature radiation box to keep the internal temperature at 338-342°C;

[0016] S1.3. Use an electron accelerator to irradiate polytetrafluoroethylene. When the irradiation dose reaches 190-210 kGy, stop irradiation to obtain cross-linked polytetrafluoroethylene, that is, cross-linked polytetrafluoroethylene material.

[0017] In step S1.1, the protective gas introduced is nitrogen, and the introduction rate is 8-10 L / min.

[0018] In step S1, the first reinforcing resin and the second reinforcing resin are both polyalkyl aryl silicone resins, and the buffer material is high temperature resistant rubber.

[0019] In step S2, the copper foil is roughened as follows:

[0020] S2.1. Pour a sulfuric acid copper plating solution containing a quaternary ammonium salt polymer into the pickling tank and transport the copper foil into the pickling tank at a speed of 10-20 m / min;

[0021] S2.2, average anode current density is 10-40A / dm 2 Electrolysis is performed for 5-20 seconds to precipitate fine copper particles on the surface of the copper foil, completing the coarsening.

[0022] In step S2.1, the copper concentration of the sulfate copper plating solution is 5-22 g / L, the sulfuric acid concentration is 50-150 g / L, the quaternary ammonium salt polymer concentration is 5-50 mg / L, and the chloride ion concentration is 20-100 mg / L.

[0023] In step S3, the pressure of the hot press is controlled at 30-60 kgf / m 2 , the speed of the hot press is controlled at 25-45m / min.

[0024] In step S3, the temperature of the drying box is controlled at 60-160°C.

[0025] In step S4, the insulating coating is Teflon coating, and the thickness of the insulating coating is 0.02-0.06 μm.

[0026] In step S4, the length of the cut metal strip is the same as the length of the high-frequency and high-speed flexible copper-clad laminate substrate.

[0027] Compared with the existing technology, this method for improving the tensile strength of PTFE high-frequency and high-speed flexible copper-clad laminate substrate has the following advantages:

[0028] The copper-clad laminate substrate produced by the present invention improves its own strength and tensile properties through the first reinforcing resin and the second reinforcing resin. When facing external force or impact, the flexible material and the buffer material are used to reduce shock, reduce damage caused by the external force or impact, and make it less likely to break. In addition, the surrounding metal frame can greatly improve the tensile strength of the copper-clad laminate substrate. At the same time, the copper-clad laminate substrate has better heat dissipation performance, can evenly conduct heat, and effectively prevent heat from being concentrated in one place, thereby solving the problems of low tensile strength and poor heat dissipation performance of some existing flexible copper-clad laminates. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a structural schematic diagram of the finished copper clad laminate substrate in the present invention.

[0030] Figure 2 It is a structural schematic diagram of the metal frame in the present invention.

[0031] Figure 3 It is a structural schematic diagram of the finished copper clad laminate substrate in the present invention.

[0032] Figure 4 This invention Figure 3 Schematic diagram of the enlarged structure at point A in the middle.

[0033] In the figure, 1. Metal frame; 201. Copper foil; 202. First thermal conductive adhesive film; 203. Flexible material; 204. Second thermal conductive adhesive film; 205. First reinforcing resin; 206. Third thermal conductive adhesive film; 207. Second reinforcing resin; 208. Fourth thermal conductive adhesive film; 209. Buffer material; 210. Fifth thermal conductive adhesive film; 211. Cross-linked polytetrafluoroethylene substrate; 3. Insulating coating. DETAILED DESCRIPTION

[0034] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical solutions of the present invention, but the present invention is not limited to these embodiments.

[0035] Example 1:

[0036] A method for improving the tensile strength of a PTFE high-frequency, high-speed, flexible copper-clad laminate substrate comprises the following steps:

[0037] S1. A polytetrafluoroethylene material is subjected to radiation cross-linking treatment to obtain cross-linked polytetrafluoroethylene, i.e., a cross-linked polytetrafluoroethylene substrate 211. A fifth thermally conductive adhesive film 210 is uniformly coated on the surface of the cross-linked polytetrafluoroethylene substrate 211 using a coating machine at a speed of 40 r / min and a temperature of 100° C. A buffer material 209 is then coated on the surface of the fifth thermally conductive adhesive film 210. A fourth thermally conductive adhesive film 208 is then coated on the surface of the buffer material 209. A second reinforcing resin 207 is then coated on the third thermally conductive adhesive film 206 to obtain a copper clad laminate substrate A.

[0038] The specific steps of radiation cross-linking treatment of polytetrafluoroethylene materials are:

[0039] S1.1. Place polytetrafluoroethylene into a high-temperature radiation box, seal the box, and then introduce protective gas into the box;

[0040] S1.2. Control the temperature inside the high-temperature radiation box to keep the internal temperature at 338°C;

[0041] S1.3. Irradiating polytetrafluoroethylene using an electron accelerator until the irradiation reaches 190 kGy, and then stopping the irradiation to obtain cross-linked polytetrafluoroethylene, i.e., cross-linked polytetrafluoroethylene substrate 211;

[0042] S2. Using a coating machine at a speed of 50 r / min and at 110° C., a second thermally conductive adhesive film 204 is uniformly coated on the top of the copper-clad laminate substrate A. Then, a flexible material 203 coated with the first thermally conductive adhesive film 202 is connected to the top of the second thermally conductive adhesive film 204. Finally, a roughened copper foil 201 is connected to the first thermally conductive adhesive film 202 to obtain a copper-clad laminate substrate B.

[0043] The roughening process steps of copper foil 201 are as follows:

[0044] S2.1. Pour a sulfuric acid copper plating solution containing a quaternary ammonium salt polymer into the pickling tank, and transport the copper foil 201 into the pickling tank at a speed of 10 m / min;

[0045] S2.2, average anode current density is 15A / dm 2 Electrolysis is performed for 5 seconds to precipitate fine copper particles on the surface of the copper foil 201, completing the roughening process.

[0046] S3, the copper clad laminate substrate B obtained in step S2 is hot pressed by a roller hot press to obtain a copper clad laminate substrate C, wherein the hot press temperature is controlled within the range of 110°C and the hot press pressure is controlled within the range of 30kgf / m 2 , the speed of the hot press is controlled at 25m / min, and then the copper clad laminate substrate C is placed in a drying oven for curing for 5h to obtain a high-frequency and high-speed flexible copper clad laminate substrate;

[0047] S4. After the metal strip has been subjected to the flanging process, an electrostatic spraying process is used to spray an insulating coating 3 on the metal strip. The insulating coating 3 is a Teflon coating, and the thickness of the insulating coating 3 is 0.02 μm. The Teflon coating has excellent chemical stability, corrosion resistance, sealing, high lubricity and non-stickiness, electrical insulation and good anti-aging resistance. It can be sprayed on the surface of the metal frame 1 to improve the insulation and aging resistance of the metal frame 1, thereby extending the service life of the copper clad laminate. The metal strip is then cut and bent and coated on the surface of a high-frequency, high-speed flexible copper clad laminate substrate. During the coating process, a two-component epoxy resin sealing insulating glue is applied between the metal strip and the substrate to connect the metal strip to the substrate.

[0048] S5. Weld the cut points of the metal strip together through a welding process, so that the metal frame 1 is covered on the high-frequency and high-speed flexible copper-clad laminate substrate, thereby obtaining a high-frequency and high-speed flexible copper-clad laminate substrate with higher tensile strength.

[0049] Example 2:

[0050] A method for improving the tensile strength of a PTFE high-frequency, high-speed, flexible copper-clad laminate substrate comprises the following steps:

[0051] S1. A polytetrafluoroethylene material is subjected to radiation cross-linking treatment to obtain cross-linked polytetrafluoroethylene, i.e., a cross-linked polytetrafluoroethylene substrate 211. A fifth thermally conductive adhesive film 210 is uniformly coated on the surface of the cross-linked polytetrafluoroethylene substrate 211 using a coating machine at a speed of 55 r / min and a temperature of 125° C. A buffer material 209 is then coated on the surface of the fifth thermally conductive adhesive film 210. A fourth thermally conductive adhesive film 208 is then coated on the surface of the buffer material 209. A second reinforcing resin 207 is then coated on the third thermally conductive adhesive film 206 to obtain a copper clad laminate substrate A.

[0052] The specific steps of radiation cross-linking treatment of polytetrafluoroethylene materials are:

[0053] S1.1. Place the polytetrafluoroethylene in a high-temperature radiation box, seal the box, and then introduce nitrogen as a protective gas into the box at a rate of 8 L / min.

[0054] S1.2. Control the temperature inside the high-temperature radiation box to keep the internal temperature at 340°C;

[0055] S1.3. Irradiate polytetrafluoroethylene using an electron accelerator. When the irradiation dose reaches 200 kGy, the irradiation is stopped to obtain cross-linked polytetrafluoroethylene, i.e., cross-linked polytetrafluoroethylene substrate 211.

[0056] S2. Using a coating machine at a speed of 60 r / min and a temperature of 125° C., a second thermally conductive adhesive film 204 is uniformly coated on the top of the copper-clad laminate substrate A. Then, a flexible material 203 coated with the first thermally conductive adhesive film 202 is connected to the top of the second thermally conductive adhesive film 204. Finally, a roughened copper foil 201 is connected to the first thermally conductive adhesive film 202 to obtain a copper-clad laminate substrate B.

[0057] The roughening process steps of copper foil 201 are as follows:

[0058] S2.1. Pour a sulfuric acid copper plating solution containing a quaternary ammonium salt polymer into the pickling tank and transport the copper foil 201 into the pickling tank at 15 m / min. The sulfuric acid copper plating solution has a copper concentration of 5 g / L, a sulfuric acid concentration of 50 g / L, a quaternary ammonium salt polymer concentration of 5 mg / L, and a chloride ion concentration of 20 mg / L.

[0059] S2.2, average anode current density is 20A / dm 2 Electrolysis is performed for 15 seconds to precipitate fine copper particles on the surface of the copper foil 201, completing the roughening process.

[0060] S3, the copper clad laminate substrate B obtained in step S2 is hot pressed by a roller hot press to obtain a copper clad laminate substrate C, wherein the hot press temperature is controlled within the range of 120°C and the hot press pressure is controlled within the range of 50kgf / m 2 , the speed of the hot press is controlled at 35m / min, and then the copper clad laminate substrate C is placed in a drying oven and cured at 120°C for 8h to obtain a high-frequency and high-speed flexible copper clad laminate substrate;

[0061] S4. After the metal strip has been subjected to the flanging process, an electrostatic spraying process is used to spray an insulating coating 3 on the metal strip. The insulating coating 3 is a Teflon coating, and the thickness of the insulating coating 3 is 0.05 μm. The Teflon coating has excellent chemical stability, corrosion resistance, sealing, high lubricity and non-stickiness, electrical insulation and good anti-aging resistance. It can be sprayed on the surface of the metal frame 1 to improve the insulation and aging resistance of the metal frame 1, thereby extending the service life of the copper clad laminate. The metal strip is then cut and bent and coated on the surface of a high-frequency, high-speed flexible copper clad laminate substrate. During the coating process, a two-component epoxy resin sealing insulating glue is applied between the metal strip and the substrate to connect the metal strip to the substrate.

[0062] S5. Weld the cut points of the metal strip together through a welding process, so that the metal frame 1 is covered on the high-frequency and high-speed flexible copper-clad laminate substrate, thereby obtaining a high-frequency and high-speed flexible copper-clad laminate substrate with higher tensile strength.

[0063] Example 3:

[0064] A method for improving the tensile strength of a PTFE high-frequency, high-speed, flexible copper-clad laminate substrate comprises the following steps:

[0065] S1. Take a polytetrafluoroethylene material and subject it to radiation cross-linking treatment to obtain cross-linked polytetrafluoroethylene, that is, a cross-linked polytetrafluoroethylene substrate 211. Use a coating machine to evenly coat the surface of the cross-linked polytetrafluoroethylene substrate 211 with a fifth thermally conductive adhesive film 210. The coating machine speed is 80 r / min and the temperature is 135°C. Then, a buffer material 209 is coated on the surface of the fifth thermally conductive adhesive film 210. Thereafter, a fourth thermally conductive adhesive film 208 is coated on the surface of the buffer material 209. A second reinforcing resin 207 is coated on the third thermally conductive adhesive film 206 to obtain a copper clad laminate substrate A. The first reinforcing resin 205 and the second reinforcing resin 207 are both polyalkyl aryl silicone resins. The buffer material 209 is a high-temperature resistant rubber. The properties of polyalkyl silicone resin and polyaryl silicone resin can be changed by adding one type of resin to the other type of resin to form polyalkylaryl silicone resin. In fact, it is not a simple mixture, but the alkyl and aryl groups are directly connected to the same silicon atom during synthesis, or a copolymer is generated by hydrolysis and co-condensation of alkyl and aryl chlorosilanes. Polyalkylaryl silicone resin has better mechanical properties and hardness than pure alkyl or aryl silicone resins. High-temperature resistant rubber has the shock-absorbing properties and high-temperature resistance of rubber. Flexible material 203 is sponge. Sponge can not only buffer and reduce shock, but also is softer, increasing the overall flexibility and tensile strength of the copper clad laminate.

[0066] The specific steps of radiation cross-linking treatment of polytetrafluoroethylene materials are:

[0067] S1.1. Place the polytetrafluoroethylene in a high-temperature radiation box, seal the box, and then introduce nitrogen as a protective gas into the box at a rate of 10 L / min;

[0068] S1.2. Control the temperature inside the high-temperature radiation box to keep the internal temperature at 342°C;

[0069] S1.3. Irradiating polytetrafluoroethylene using an electron accelerator until the irradiation dose reaches 210 kGy is stopped to obtain cross-linked polytetrafluoroethylene, i.e., cross-linked polytetrafluoroethylene substrate 211. High-temperature radiation cross-linking polytetrafluoroethylene has the advantages of improving its cross-linking efficiency, wear resistance, radiation resistance, and tensile strength, thereby improving the tensile strength of the copper clad laminate;

[0070] S2. Using a coating machine at a speed of 90 r / min and a temperature of 135° C., a second thermally conductive adhesive film 204 is uniformly coated on the top of the copper-clad laminate substrate A. Then, a flexible material 203 coated with the first thermally conductive adhesive film 202 is connected to the top of the second thermally conductive adhesive film 204. Finally, a roughened copper foil 201 is connected to the first thermally conductive adhesive film 202 to obtain a copper-clad laminate substrate B.

[0071] The roughening process steps of copper foil 201 are as follows:

[0072] S2.1. A sulfuric acid copper plating solution containing a quaternary ammonium salt polymer is poured into the pickling tank, and the copper foil 201 is transported into the pickling tank at 20 m / min. The sulfuric acid copper plating solution has a copper concentration of 22 g / L, a sulfuric acid concentration of 150 g / L, a quaternary ammonium salt polymer concentration of 50 mg / L, and a chloride ion concentration of 100 mg / L.

[0073] S2.2, average anode current density is 40A / dm 2 Electrolysis is performed for 20 seconds to precipitate fine copper particles on the surface of the copper foil 201, completing the roughening process.

[0074] S3, the copper clad laminate substrate B obtained in step S2 is hot pressed by a roller hot press to obtain a copper clad laminate substrate C, wherein the hot press temperature is controlled within the range of 180°C and the hot press pressure is controlled within the range of 60kgf / m 2 , the speed of the hot press is controlled at 45m / min, and then the copper clad laminate substrate C is placed in a drying oven and cured at 160°C for 12 hours to obtain a high-frequency and high-speed flexible copper clad laminate substrate;

[0075] S4. After the metal strip has been subjected to the flanging process, an electrostatic spraying process is used to spray an insulating coating 3 on the metal strip. The insulating coating 3 is a Teflon coating, and the thickness of the insulating coating 3 is 0.06 μm. The Teflon coating has excellent chemical stability, corrosion resistance, sealing, high lubricity and non-stickiness, electrical insulation and good anti-aging resistance. It can be sprayed on the surface of the metal frame 1 to improve the insulation and aging resistance of the metal frame 1, thereby extending the service life of the copper clad laminate. The metal strip is then cut, bent and coated on the surface of the high-frequency and high-speed flexible copper clad laminate substrate. During the coating process, a two-component epoxy resin sealing insulating glue is applied between the metal strip and the substrate to connect the metal strip to the substrate. The length of the cut metal strip is the same as the length of the high-frequency and high-speed flexible copper clad laminate substrate to prevent the metal strip from being too long and causing the two cut surfaces to be unable to close;

[0076] S5. Weld the cut points of the metal strip together through a welding process, so that the metal frame 1 is covered on the high-frequency and high-speed flexible copper-clad laminate substrate, thereby obtaining a high-frequency and high-speed flexible copper-clad laminate substrate with higher tensile strength.

[0077] The specific embodiments described herein are merely illustrative of the spirit of the present invention. Persons skilled in the art may make various modifications, additions, or substitutions to the described specific embodiments without departing from the spirit of the present invention or exceeding the scope of the appended claims.

Claims

1. A method for improving the tensile strength of a PTFE high-frequency, high-speed, flexible copper-clad laminate substrate, characterized in that: The preparation method thereof comprises the following steps: S1. A polytetrafluoroethylene material is subjected to radiation cross-linking treatment to obtain cross-linked polytetrafluoroethylene, namely a cross-linked polytetrafluoroethylene substrate (211). A fifth thermal conductive adhesive film (210) is uniformly coated on the surface of the cross-linked polytetrafluoroethylene substrate (211) using a coating machine, the speed of the coating machine being 40-80 r / min and the temperature being 100-135° C. A buffer material (209) is then coated on the surface of the fifth thermal conductive adhesive film (210). A fourth thermal conductive adhesive film (208) is then coated on the surface of the buffer material (209), and a second reinforcing resin (207) is coated on the third thermal conductive adhesive film (206) to obtain a copper clad laminate substrate A. S2, using a coating machine at a speed of 40-90 r / min at 100-135° C. to uniformly coat the second thermally conductive adhesive film (204) on the top of the copper-clad laminate substrate A, then connecting the flexible material (203) coated with the first thermally conductive adhesive film (202) on the top to the second thermally conductive adhesive film (204), and then connecting the roughened copper foil (201) to the first thermally conductive adhesive film (202) to obtain the copper-clad laminate substrate B; S3, hot pressing the copper clad laminate substrate B obtained in step S2 with a roller hot press to obtain a copper clad laminate substrate C, wherein the hot press temperature is controlled within the range of 100-180° C., and then placing the copper clad laminate substrate C in a drying oven for curing treatment for 5-12 hours to obtain a high-frequency, high-speed, flexible copper clad laminate substrate; S4, after flanging the metal strip, spray an insulating coating (3) on the metal strip using an electrostatic spraying process, then cut and bend the metal strip and coat it on the surface of a high-frequency, high-speed, flexible copper-clad laminate substrate. During the coating process, apply a two-component epoxy resin sealing insulating glue between the metal strip and the substrate to connect the metal strip to the substrate; S5. Welding the cut points of the metal strip together through a welding process, so that the metal frame (1) is covered on the high-frequency and high-speed flexible copper-clad laminate substrate, thereby obtaining a high-frequency and high-speed flexible copper-clad laminate substrate with higher tensile strength.

2. The method for improving the tensile strength of a PTFE high-frequency, high-speed, flexible copper-clad laminate according to claim 1, wherein: In step S1, the specific steps of the radiation cross-linking treatment of the polytetrafluoroethylene material are: S1.

1. Place polytetrafluoroethylene into a high-temperature radiation box, seal the box, and then introduce protective gas into the box; S1.

2. Control the temperature inside the high-temperature radiation box to keep the internal temperature at 338-342°C; S1.

3. Using an electron accelerator to irradiate polytetrafluoroethylene, when the irradiation dose reaches 190-210 kGy, the irradiation is stopped to obtain cross-linked polytetrafluoroethylene, i.e., cross-linked polytetrafluoroethylene substrate (211).

3. The method for improving the tensile strength of a PTFE high-frequency, high-speed, flexible copper-clad laminate according to claim 2, wherein: In step S1.1, the protective gas introduced is nitrogen, and the introduction rate is 8-10 L / min.

4. The method for improving the tensile strength of a PTFE high-frequency, high-speed, flexible copper-clad laminate according to claim 1, wherein: In step S1, the first reinforcing resin (205) and the second reinforcing resin (207) are both polyalkyl aryl silicone resins, and the buffer material (209) is high-temperature resistant rubber.

5. The method for improving the tensile strength of a PTFE high-frequency, high-speed, flexible copper-clad laminate according to claim 1, wherein: In step S2, the roughening treatment step of the copper foil (201) is as follows: S2.1, pouring a sulfuric acid copper plating solution containing a quaternary ammonium salt polymer into the pickling tank, and transporting the copper foil (201) into the pickling tank at a speed of 10-20 m / min; S2.2, average anode current density is 10-40A / dm 2 The electrolysis is performed for 5-20 seconds, and fine copper particles are precipitated on the surface of the copper foil (201), thereby completing the coarsening.

6. The method for improving the tensile strength of a PTFE high-frequency, high-speed, flexible copper-clad laminate substrate according to claim 5, wherein: In step S2.1, the copper concentration of the sulfate copper plating solution is 5-22 g / L, the sulfuric acid concentration is 50-150 g / L, the quaternary ammonium salt polymer concentration is 5-50 mg / L, and the chloride ion concentration is 20-100 mg / L.

7. The method for improving the tensile strength of a PTFE high-frequency, high-speed, flexible copper-clad laminate according to claim 1, wherein: In step S3, the pressure of the hot press is controlled at 30-60 kgf / m 2 , the speed of the hot press is controlled at 25-45m / min.

8. The method for improving the tensile strength of a PTFE high-frequency, high-speed, flexible copper-clad laminate according to claim 1, wherein: In step S3, the temperature of the drying box is controlled at 60-160°C.

9. The method for improving the tensile strength of a PTFE high-frequency, high-speed, flexible copper-clad laminate according to claim 1, wherein: In the step S4, the insulating coating (3) is Teflon coating, and the thickness of the insulating coating (3) is 0.02-0.06 μm.

10. The method for improving the tensile strength of a PTFE high-frequency, high-speed, flexible copper-clad laminate substrate according to claim 1, wherein: In step S4, the length of the cut metal strip is the same as the length of the high-frequency and high-speed flexible copper-clad laminate substrate.

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