CN117779466A - Laminated fluorine film for flexible copper-clad plate and preparation method thereof - Google Patents
Laminated fluorine film for flexible copper-clad plate and preparation method thereof Download PDFInfo
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- CN117779466A CN117779466A CN202211170140.4A CN202211170140A CN117779466A CN 117779466 A CN117779466 A CN 117779466A CN 202211170140 A CN202211170140 A CN 202211170140A CN 117779466 A CN117779466 A CN 117779466A
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- glass fiber
- fiber cloth
- fluorine film
- polytetrafluoroethylene
- laminated
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- 238000002360 preparation method Methods 0.000 title abstract description 7
- 125000001153 fluoro group Chemical class F* 0.000 title 1
- 229920001343 polytetrafluoroethylene Polymers 0.000 claims abstract description 55
- 239000004810 polytetrafluoroethylene Substances 0.000 claims abstract description 55
- 239000004744 fabric Substances 0.000 claims abstract description 54
- 239000003365 glass fiber Substances 0.000 claims abstract description 54
- 150000002221 fluorine Chemical class 0.000 claims abstract description 49
- -1 polytetrafluoroethylene Polymers 0.000 claims abstract description 44
- 229910052710 silicon Inorganic materials 0.000 claims abstract description 37
- 239000010703 silicon Substances 0.000 claims abstract description 37
- 238000000034 method Methods 0.000 claims abstract description 8
- 239000011248 coating agent Substances 0.000 claims abstract description 7
- 238000000576 coating method Methods 0.000 claims abstract description 7
- 238000005245 sintering Methods 0.000 claims abstract description 7
- YCKRFDGAMUMZLT-UHFFFAOYSA-N Fluorine atom Chemical compound [F] YCKRFDGAMUMZLT-UHFFFAOYSA-N 0.000 claims abstract description 4
- 229910052731 fluorine Inorganic materials 0.000 claims abstract description 4
- 239000011737 fluorine Substances 0.000 claims abstract description 4
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 8
- 239000011889 copper foil Substances 0.000 claims description 6
- 238000004519 manufacturing process Methods 0.000 claims description 5
- 239000002245 particle Substances 0.000 claims description 5
- 239000011521 glass Substances 0.000 claims description 3
- 238000003475 lamination Methods 0.000 claims description 3
- 239000012528 membrane Substances 0.000 claims 1
- 238000012360 testing method Methods 0.000 abstract description 10
- 230000005540 biological transmission Effects 0.000 abstract description 2
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 29
- 238000002156 mixing Methods 0.000 description 12
- 230000000052 comparative effect Effects 0.000 description 8
- 238000004891 communication Methods 0.000 description 3
- 239000003989 dielectric material Substances 0.000 description 3
- 238000010998 test method Methods 0.000 description 3
- 229910052802 copper Inorganic materials 0.000 description 2
- 239000010949 copper Substances 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 238000013329 compounding Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000010295 mobile communication Methods 0.000 description 1
- 238000011056 performance test Methods 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 238000007711 solidification Methods 0.000 description 1
- 230000008023 solidification Effects 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
- 239000011800 void material Substances 0.000 description 1
Abstract
The invention relates to the technical field of copper-clad plates, in particular to a laminated fluorine film for a flexible copper-clad plate and a preparation method thereof. The laminated fluorine film comprises: the glass fiber cloth and polytetrafluoroethylene layers are arranged on two sides of the glass fiber cloth in a contact manner; the gaps of the polytetrafluoroethylene layer and the glass fiber cloth contain spherical silicon; dk of the spherical silicon is 3.5 or less, and Df is 0.001 or less; the thickness ratio of the glass fiber cloth to the polytetrafluoroethylene layer is 1:3-9. The preparation method comprises the following steps: and coating polytetrafluoroethylene solution containing spherical silicon on the glass fiber cloth, and then solidifying and sintering. The laminated fluorine film provided by the invention has a lower thermal expansion coefficient and stronger tensile strength, overcomes the problem of poor CTE performance and structural strength of a polytetrafluoroethylene film, solves the problem of dimensional stability and flexibility in the process of testing the FPC at the rear end of the fluorine FCCL, and reduces the transmission loss on the basis of meeting the reliability of the FCCL process.
Description
Technical Field
The invention relates to the technical field of copper-clad plates, in particular to a laminated fluorine film for a flexible copper-clad plate and a preparation method thereof.
Background
With the high development and popularization of 5G passing systems, the communication frequency bands of mobile communication equipment such as mobile phones, tablets and the like are continuously increased, and the frequency is expanded from the original 800 MHz-3G to 5G and millimeter wave frequency bands (28G, 40G); in addition, in the rapid development of automobile communication, the increase of the number of communication channels has put higher demands on low-loss high-frequency flexible boards in the high-frequency or even microwave field.
Flexible Copper Clad Laminate (FCCL) as a substrate for high frequency low loss flexible board, in addition to the performance required for general FCCL (peelingOff strength, electrical properties, etc.), it is also desirable to have a stable dielectric constant (Dk) and extremely low dielectric loss tangent angle (Df). Polytetrafluoroethylene (PTFE) is a symmetrical structure that can provide good electrical properties. The dielectric constant (1 MHz) is as low as 2.1, and the dielectric loss tangent is 10 -4 In all resins, PTFE has the smallest dielectric constant (Dk) and dielectric loss tangent (Df), and is therefore an ideal low-loss dielectric material for electrical performance.
While polytetrafluoroethylene has excellent dielectric constant (Dk) and loss tangent (Df), pure polytetrafluoroethylene has a very strong Coefficient of Thermal Expansion (CTE), which reaches 150-200; and the Tensile strength (Tensile strength) of the pure polytetrafluoroethylene is 20-30 Mpa. Therefore, the pure polytetrafluoroethylene film cannot be directly applied to FCCL, and the polytetrafluoroethylene film needs to be designed and optimized to improve the thermal expansion coefficient and the tensile strength.
How to design a polytetrafluoroethylene dielectric material for a flexible copper-clad plate to solve the defects of the thermal expansion coefficient and the tensile strength of polytetrafluoroethylene, and simultaneously, the dielectric material has good flexibility, which becomes a technical problem to be solved in the field.
Disclosure of Invention
In view of this, the present invention provides a laminated fluorine film usable for a flexible copper-clad plate, comprising: the glass fiber cloth and polytetrafluoroethylene layers are arranged on two sides of the glass fiber cloth in a contact manner;
the gaps of the polytetrafluoroethylene layer and the glass fiber cloth contain spherical silicon;
dk of the spherical silicon is 3.5 or less, and Df is 0.001 or less;
the thickness ratio of the glass fiber cloth to the polytetrafluoroethylene layer is 1:3-9.
According to the invention, a lamination framework is realized by adopting glass fiber cloth and a polytetrafluoroethylene layer containing spherical silicon, and the tensile strength of a lamination fluorine film can be obviously improved and the flexibility of the material can be increased by controlling the thickness ratio of the glass fiber cloth to the polytetrafluoroethylene layer containing spherical silicon to be 1:3-9; meanwhile, by compounding the polytetrafluoroethylene layer added with the low-loss spherical silicon, the CTE of the laminated fluorine film can be greatly reduced, so that the laminated fluorine film with low thermal expansion coefficient and high tensile strength is prepared. In addition, the low-loss spherical silicon doped in the invention can fully exert the low-loss characteristic of polytetrafluoroethylene in the range of the thickness ratio, thereby improving the comprehensive performance of the laminated fluorine film.
As a preferable embodiment of the invention, the thickness ratio of the glass fiber cloth to the polytetrafluoroethylene layer is 1:3-5.
As a preferred embodiment of the invention, the weight ratio of the spherical silicon to the polytetrafluoroethylene in the polytetrafluoroethylene layer is 0.4-2.5:1, more preferably 1-1.5:1.
As a preferred embodiment of the present invention, the thickness of the laminated fluorine film is 50 to 150 μm.
When the thickness of the laminated fluorine film is controlled within the range, the thin and flexible performance requirements of the flexible copper-clad plate can be better met.
As a preferred embodiment of the present invention, the glass cloth has a void size of 50 to 200 microns.
By controlling the size of the gaps of the glass fiber cloth, ball silicon can be filled and pass through the gaps of the glass fiber cloth, so that the CTE of the laminated fluorine film is further reduced, and the tensile strength is improved. The gaps are formed by crossing adjacent warps and wefts in the same plane.
As a preferred embodiment of the present invention, the glass cloth has a thickness of 10 to 20 μm.
As a preferred embodiment of the present invention, the glass fiber cloth has a wire diameter of 10 to 20 μm.
As a preferable embodiment of the invention, the warp and weft density ratio of the glass fiber cloth is 0.5-1.5:1.
As a preferred embodiment of the present invention, the particle size of the silicon spheres is 0.5 to 20 microns, preferably 0.5 to 10 microns.
When the particle size of the spherical silicon is selected, the spherical silicon can be well doped and filled in the gaps of the glass fiber cloth, and the performance of the laminated fluorine film can be further improved.
Further, the present invention also provides a method for preparing a laminated fluorine film in any of the above embodiments, comprising: and coating polytetrafluoroethylene solution containing spherical silicon on the glass fiber cloth, and then solidifying and sintering.
As a preferred embodiment of the present invention, the curing temperature is 130 to 170 ℃.
As a preferred embodiment of the present invention, the sintering temperature is 340 to 380 ℃.
As a more preferred embodiment of the present invention, the method for producing a laminated fluorine film comprises:
(1) Selecting spherical silicon with the grain diameter of 0.5-20 micrometers; dk of the spherical silicon is 3.5 or less, and Df is 0.001 or less; then mixing the spherical silicon with polytetrafluoroethylene solution to prepare a blending solution; wherein the weight ratio of the spherical silicon to the polytetrafluoroethylene is 0.4-2.5:1;
(2) Designing glass fiber cloth, and controlling the thickness of the glass fiber cloth to be 10-20 microns, the wire diameter to be 10-20 microns, the warp and weft density ratio to be 0.5-1.5:1 and the gap size of the glass fiber cloth to be 50-200 microns;
(3) Coating the blending solution on the surface of glass fiber cloth, and controlling the overall thickness to be 50-150 microns; controlling the thickness ratio of the glass fiber cloth to the polytetrafluoroethylene layer to be 1:3-9;
(4) The glass fiber coated with the blending solution is arranged at 130-170 ℃ for solidification, and then sintered at 340-380 ℃.
Preferably, curing for 3-8 min;
preferably, sintering is carried out for 5 to 15 minutes.
When the coating is carried out in the specific implementation process, the blending solution is uniformly coated on the surface of the glass fiber cloth as much as possible, so that the performance of the laminated fluorine film can be further enhanced.
Further, the invention also provides a flexible copper-clad plate, which contains the laminated fluorine film in any one of the embodiments or the laminated fluorine film prepared by any one of the embodiments.
As a preferred embodiment of the present invention, the flexible copper clad laminate comprises: and the laminated fluorine film and the copper foils are arranged on two sides of the laminated fluorine film in a contact manner.
Compared with the prior art, the invention has the beneficial effects that:
the laminated fluorine film provided by the invention has a lower thermal expansion coefficient and stronger tensile strength, overcomes the problem of poor CTE performance and structural strength of a polytetrafluoroethylene film, solves the problem of dimensional stability and MIT (flexibility) in the process of testing the FPC at the rear end of the fluorine FCCL, and reduces the transmission loss on the basis of meeting the reliability of the FCCL process.
Detailed Description
The following examples are illustrative of the invention and are not intended to limit the scope of the invention.
The examples are not intended to identify the particular technology or conditions, and are either conventional or are carried out according to the technology or conditions described in the literature in this field or are carried out according to the product specifications. The reagents and instruments used, etc. are not identified to the manufacturer and are conventional products available for purchase by regular vendors.
Example 1
The embodiment provides a laminated fluorine film for a flexible copper-clad plate, which is prepared by the following steps:
(1) Selecting low-loss spherical silicon with the particle size D50 of 4 microns; dk of the low-loss spherical silicon is 3.5, and Df is 0.001; mixing spherical silicon with PTFE solution to prepare a blending solution; the weight ratio of the spherical silicon to the PTFE is 55:45;
(2) Designing glass fiber cloth, controlling the thickness of the glass fiber cloth to be 17 microns, the wire diameter to be 15 microns, the ratio of the warp to the weft to be 0.8:1 and the gap size of the glass fiber cloth to be 100 microns;
(3) Uniformly coating the blending solution on the surface of glass fiber cloth, and controlling the overall thickness to be 100 micrometers; the thickness ratio of the glass fiber cloth to the polytetrafluoroethylene layer is controlled to be 1:5, a step of;
(4) The glass fibers coated with the blend solution were cured at 160℃for 8min and then sintered at 360℃for 20min.
Through testing, the thickness ratio of the glass fiber cloth to the polytetrafluoroethylene layer in the obtained laminated fluorine film is 1:5; the weight ratio of the spherical silicon to the PTFE is 55:45.
The embodiment also provides a flexible copper-clad plate, which is prepared by the following steps: copper foil is adhered to both sides of the prepared laminated fluorine film.
Example 2
The embodiment provides a laminated fluorine film for a flexible copper-clad plate, which is prepared by the following steps:
(1) Selecting low-loss spherical silicon with the particle size D50 of 4 microns; dk of the low-loss spherical silicon is 3.5, and Df is 0.001; mixing spherical silicon with PTFE solution to prepare a blending solution; the weight ratio of the spherical silicon to the PTFE is 62:38;
(2) Designing glass fiber cloth, controlling the thickness of the glass fiber cloth to be 17 microns, the wire diameter to be 15 microns, the ratio of the warp to the weft to be 1:1 and the gap size of the glass fiber cloth to be 100 microns;
(3) Uniformly coating the blending solution on the surface of glass fiber cloth, and controlling the overall thickness to be 100 micrometers; controlling the thickness ratio of the glass fiber cloth to the polytetrafluoroethylene layer to be 1:5;
(4) Arranging the glass fiber coated with the blending solution, curing for 15min at 150 ℃, and then sintering for 30min at 360 ℃;
through testing, the thickness ratio of the glass fiber cloth to the polytetrafluoroethylene layer in the obtained laminated fluorine film is 1:5; the weight ratio of spherical silicon to PTFE was 62:38.
The embodiment also provides a flexible copper-clad plate, which is prepared by the following steps: copper foil is adhered to both sides of the prepared laminated fluorine film.
Example 3
The embodiment provides a laminated fluorine film for a flexible copper-clad plate, and the specific preparation method is different from that of embodiment 1 only in that:
in the step (3), the thickness ratio of the glass fiber cloth to the polytetrafluoroethylene layer is controlled to be 1:3.
Through testing, the thickness ratio of the glass fiber cloth to the polytetrafluoroethylene layer in the obtained laminated fluorine film is 1:3; the weight ratio of the spherical silicon to the PTFE is 55:45.
The embodiment also provides a flexible copper-clad plate, which is prepared by the following steps: copper foil is adhered to both sides of the prepared laminated fluorine film.
Example 4
The embodiment provides a laminated fluorine film for a flexible copper-clad plate, and the specific preparation method is different from that of embodiment 1 only in that:
in the step (3), the thickness ratio of the glass fiber cloth to the polytetrafluoroethylene layer is controlled to be 1:9.
Through testing, the thickness ratio of the glass fiber cloth to the polytetrafluoroethylene layer in the obtained laminated fluorine film is 1:9; the weight ratio of the spherical silicon to the PTFE is 55:45.
The embodiment also provides a flexible copper-clad plate, which is prepared by the following steps: copper foil is adhered to both sides of the prepared laminated fluorine film.
Comparative example 1
This comparative example provides a laminated fluorine film, and the specific production method is different from example 1 only in that: in the step (3), the thickness ratio of the glass fiber cloth to the polytetrafluoroethylene layer is controlled to be 1:2.
through testing, the thickness ratio of the glass fiber cloth to the polytetrafluoroethylene layer in the obtained laminated fluorine film is 1:2; the weight ratio of the spherical silicon to the PTFE is 55:45.
Comparative example 2
This comparative example provides a laminated fluorine film, and the specific production method is different from example 1 only in that: does not contain glass fiber cloth.
Test examples
The laminated fluorine films prepared in the above examples and comparative examples were tested for thermal expansion coefficient and tensile strength and MIT (flexibility). Specifically:
test apparatus for Coefficient of Thermal Expansion (CTE): NETZSCH TMA 402 F3,
test methods reference IPC-TM-650.2.4.41;
tensile strength test equipment: shimadzu AGX-V,
test methods reference IPC-TM-650.2.4.24;
MIT (flexibility) test method was referred to JIS C6471.
The thermal expansion Coefficient (CTE), tensile strength and MIT (flexibility) performance results of the laminated fluorine films prepared in examples and comparative examples were tested as shown in table 1:
TABLE 1 Performance test results
| Project | Example 1 | Example 2 | Example 3 | Example 4 | Comparative example 1 | Comparative example 2 |
| Coefficient of Thermal Expansion (CTE) | 13.3 | 10.7 | 12.5 | 18.2 | 8.6 | 50 |
| Tensile Strength (Mpa) | 50 | 50 | 53 | 48 | 100 | 8.5 |
| MIT (flexibility) | 300 | 300 | 280 | 350 | 25 | 200 |
Therefore, the laminated fluorine film for the flexible copper-clad plate prepared by the invention has the advantages of lower thermal expansion coefficient, stronger tensile strength and higher flexibility.
While the invention has been described in detail in the foregoing general description and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that modifications and improvements can be made thereto. Accordingly, such modifications or improvements may be made without departing from the spirit of the invention and are intended to be within the scope of the invention as claimed.
Claims (10)
1. The utility model provides a lamination fluorine membrane that can be used to flexible copper-clad plate which characterized in that includes: the glass fiber cloth and polytetrafluoroethylene layers are arranged on two sides of the glass fiber cloth in a contact manner;
the gaps of the polytetrafluoroethylene layer and the glass fiber cloth contain spherical silicon;
dk of the spherical silicon is 3.5 or less, and Df is 0.001 or less;
the thickness ratio of the glass fiber cloth to the polytetrafluoroethylene layer is 1:3-9.
2. The laminated fluorine film according to claim 1, wherein the weight ratio of the spherical silicon to polytetrafluoroethylene in the polytetrafluoroethylene layer is 0.4 to 2.5:1.
3. The laminated fluorine film according to claim 1 or 2, characterized in that the thickness of the laminated fluorine film is 50 to 150 μm.
4. The laminated fluorine film according to any of claims 1 to 3, wherein the glass cloth has a thickness of 10 to 20 μm; and/or the wire diameter of the glass fiber cloth is 10-20 microns; and/or the warp and weft density ratio of the glass fiber cloth is 0.5-1.5:1; and/or the gap size of the glass fiber cloth is 50-200 micrometers.
5. The laminated fluorine film according to any of claims 1 to 4, wherein the spherical silicon has a particle diameter of 0.5 to 20 μm.
6. The method for producing a laminated fluorine film according to any one of claims 1 to 5, comprising: and coating polytetrafluoroethylene solution containing spherical silicon on the glass fiber cloth, and then solidifying and sintering.
7. The method according to claim 6, wherein the curing temperature is 130 to 170 ℃.
8. The method according to claim 6 or 7, wherein the sintering temperature is 340 to 380 ℃.
9. A flexible copper-clad laminate comprising the laminated fluorine film according to any one of claims 1 to 5 or the laminated fluorine film produced by the production method according to any one of claims 6 to 8.
10. The flexible copper-clad plate of claim 9, wherein the flexible copper-clad plate comprises: and the laminated fluorine film and the copper foils are arranged on two sides of the laminated fluorine film in a contact manner.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211170140.4A CN117779466A (en) | 2022-09-22 | 2022-09-22 | Laminated fluorine film for flexible copper-clad plate and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211170140.4A CN117779466A (en) | 2022-09-22 | 2022-09-22 | Laminated fluorine film for flexible copper-clad plate and preparation method thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117779466A true CN117779466A (en) | 2024-03-29 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202211170140.4A Pending CN117779466A (en) | 2022-09-22 | 2022-09-22 | Laminated fluorine film for flexible copper-clad plate and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117779466A (en) |
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2022
- 2022-09-22 CN CN202211170140.4A patent/CN117779466A/en active Pending
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