Prepreg, laminate and method for producing the same

Abstract

The present application relates to a prepreg composition, a prepreg, a laminate and a method for preparing the same; the prepreg composition comprises a resin, a filler and an additive, the content of magnetic substance in the resin is less than or equal to 150 ppm, the content of magnetic substance in the filler is less than or equal to 1150 ppm, the content of magnetic substance in the additive is less than or equal to 60 ppm, and the magnetic substance comprises at least one of iron, cobalt and nickel. In the prepreg composition of the present application, the content of magnetic substance in the resin, the filler and the additive is controlled, so that the laminate prepared by using the prepreg composition can effectively reduce the interference of passive intermodulation products caused by material nonlinearity, thereby improving the communication quality of the communication system.

Description

Technical Field

[0001] This invention relates to the field of electronic laminated composite materials, and in particular to prepreg compositions, prepreg sheets, laminates and their preparation methods. Background Technology

[0002] Passive intermodulation (PIM) is caused by the nonlinear characteristics of various passive devices in a transmitting system. In high-power, multi-channel systems, the nonlinearity of these passive devices can generate higher harmonics relative to the operating frequency. These harmonics mix with the operating frequency to produce a new set of frequencies, which ultimately results in a set of useless spectra in the air, thus affecting normal communication.

[0003] In recent years, with the significant increase in the number of communication systems and their users, passive intermodulation products in mobile communication systems have become one of the major parasitic interferences affecting system communication quality. Therefore, researching how to scientifically and effectively avoid the generation of passive intermodulation products is of great significance for improving the overall communication quality of the communication system. Summary of the Invention

[0004] Therefore, it is necessary to provide a prepreg composition, a prepreg, a laminate, and a method for preparing the same, in order to address the above problems. The content of magnetic materials in each component of the prepreg composition is controlled, and the laminate prepared using it can effectively reduce the interference of passive intermodulation products caused by material nonlinearity.

[0005] A prepreg composition comprising a resin, a filler, and an additive, wherein the resin contains less than or equal to 150 ppm of a magnetic substance, the filler contains less than or equal to 1150 ppm of a magnetic substance, and the additive contains less than or equal to 60 ppm of a magnetic substance, wherein the magnetic substance comprises at least one of iron, cobalt, and nickel.

[0006] In one embodiment, the resin contains iron, cobalt, and nickel at a concentration of less than or equal to 50 ppm.

[0007] In one embodiment, the filler contains less than or equal to 1000 ppm of iron, less than or equal to 100 ppm of cobalt, and less than or equal to 50 ppm of nickel.

[0008] In one embodiment, the content of iron, cobalt, and nickel in the additive is less than or equal to 20 ppm.

[0009] In one embodiment, the amount of filler in the prepreg composition is 60 to 150 parts by weight, and the amount of additive is 1 to 30 parts by weight, based on 100 parts by weight of the resin.

[0010] A prepreg comprising a reinforcing material and a prepreg composition as described above attached to the reinforcing material.

[0011] In one embodiment, the content of magnetic substance in the reinforcing material is less than or equal to 2300 ppm, the magnetic substance comprising at least one of iron, cobalt and nickel.

[0012] In one embodiment, the content of iron in the reinforcing material is less than or equal to 2000 ppm, the content of cobalt is less than or equal to 200 ppm, and the content of nickel is less than or equal to 100 ppm.

[0013] A method for preparing a laminate, comprising:

[0014] providing a prepreg as described above;

[0015] covering a metal foil on at least one surface of the prepreg and curing to make the prepreg react to form a dielectric layer, thereby obtaining a laminate.

[0016] In one embodiment, a plurality of the prepregs are provided, and the plurality of the prepregs are stacked to form a prepreg layer, and the metal foil is covered on at least one surface of the prepreg layer.

[0017] A laminate obtained by the method described above, comprising a dielectric layer and a metal foil covered on at least one surface of the dielectric layer.

[0018] In one embodiment, the content of magnetic substance in the metal foil is less than or equal to 1500 ppm, the magnetic substance comprising at least one of iron, cobalt and nickel.

[0019] In one embodiment, the metal foil comprises a copper foil, and the content of iron, cobalt and nickel in the copper foil is less than or equal to 500 ppm.

[0020] The inventors have found that the resin, the additive and the filler may be doped with trace amounts of magnetic substance such as iron, cobalt and nickel due to the production process, transportation and storage, and the raw material of the filler itself contains a relatively high amount of magnetic substance. Therefore, when the resin, the additive and the filler are mixed to prepare a laminate for application to a communication device, the magnetic substance has a high magnetic permeability and changes nonlinearly with the magnetic field, showing hysteresis characteristics, thereby generating a strong passive intermodulation product, which affects the communication quality. Based on this, the prepreg composition of the present application controls the content of magnetic substance in the resin, the filler and the additive, so that the laminate prepared by using the prepreg composition can effectively reduce the interference of passive intermodulation product in the communication device, thereby improving the communication quality. DETAILED DESCRIPTION

[0021] The pre-preg composition, prepreg, laminated board and the preparation method thereof will be further described below.

[0022] The pre-preg composition provided by the present application is mainly used for preparing the prepreg, and then the laminated board is prepared by using the prepreg. Since the content of the magnetic substance in the pre-preg composition is low, the laminated board prepared thereby can effectively reduce the interference of the passive intermodulation product caused by the material nonlinearity, thereby improving the communication quality of the communication system.

[0023] In the satellite communication system and the mobile communication system, the PIM interference of the microwave device mainly comes from the contact nonlinearity and the material nonlinearity. The applicant has found by accident through long-term and in-depth research that the resin and the additive can be doped with trace amounts of magnetic substances such as iron, cobalt and nickel due to the influence of production process, transportation and storage, and the filler itself contains a high content of magnetic substances due to the raw material. In the communication system, these magnetic substances have a large magnetic permeability and change nonlinearly with the magnetic field, showing hysteresis characteristics, and when the content is too high, a very strong passive intermodulation product can be generated.

[0024] Therefore, the pre-preg composition provided by the present application comprises resin, filler and additive, the content of the magnetic substance in the resin is less than or equal to 150 ppm, the content of the magnetic substance in the filler is less than or equal to 1150 ppm, and the content of the magnetic substance in the additive is less than or equal to 60 ppm, and the magnetic substance comprises at least one of iron, cobalt and nickel. By controlling the content of the magnetic substance in the resin, the filler and the additive, the laminated board prepared by using the pre-preg composition can effectively reduce the interference of the passive intermodulation product caused by the material nonlinearity, thereby improving the communication quality of the communication system.

[0025] It can be understood that the content of the magnetic substance in the resin, the filler and the additive is the content of the magnetic substance in the raw material of the resin, the filler and the additive. For example, the content of the magnetic substance in the resin is less than or equal to 150 ppm, which means that the content of the magnetic substance in the raw material of the resin is less than or equal to 150 ppm, not that the total content of the magnetic substance in all resin components in the pre-preg composition is less than or equal to 150 ppm.

[0026] Specifically, the content of iron, cobalt and nickel in the resin is less than or equal to 50 ppm, preferably less than 50 ppm, and further preferably less than 20 ppm. The content of iron in the filler is less than or equal to 1000 ppm, preferably less than 1000 ppm, and further preferably less than 500 ppm; the content of cobalt is less than or equal to 100 ppm, preferably less than 100 ppm, and further preferably less than 50 ppm; and the content of nickel is less than or equal to 50 ppm, preferably less than 50 ppm, and further preferably less than 20 ppm. The content of iron, cobalt and nickel in the additive is less than or equal to 20 ppm, preferably less than 20 ppm, and further preferably less than 10 ppm.

[0027] Specifically, in the prepreg composition, the amount of the filler is 60-150 parts by weight based on 100 parts by weight of the resin, and the amount of the additive is 1-30 parts by weight.

[0028] The additive includes at least one of a curing agent, a coupling agent and a co-crosslinking agent. The amount of the curing agent is 1-10 parts by weight, the amount of the coupling agent is 0-5 parts by weight, and the amount of the co-crosslinking agent is 0-20 parts by weight. The content of magnetic substances in each component of the additive is less than or equal to 60 ppm, and the content of iron, cobalt and nickel in each component of the additive is less than or equal to 20 ppm, preferably less than 10 ppm.

[0029] The resin includes at least one of polytetrafluoroethylene, polybutadiene, a copolymer of polybutadiene and styrene, polyisoprene, modified polybutadiene, a block copolymer or a graft copolymer capable of undergoing copolymerization and crosslinking reaction, a thermosetting liquid crystal resin, cyanate ester, polyphenyl ether, modified polyphenyl ether and polyimide.

[0030] The filler includes at least one of polytetrafluoroethylene, titanium dioxide, barium titanate, strontium titanate, silicon dioxide, corundum, wollastonite, solid glass microspheres, hollow glass microspheres, hollow silica microspheres, hollow titanium dioxide microspheres, synthetic glass, quartz, boron nitride, aluminum nitride, aluminum carbide, beryllium oxide, aluminum oxide, aluminum hydroxide, magnesium oxide, mica, talc and magnesium hydroxide.

[0031] The coupling agent includes at least one of a silane coupling agent, a titanate coupling agent and an aluminate coupling agent.

[0032] The curing agent includes at least one of 2,5-dimethyl-2,5-di( benzeneperoxide) hexane, di-tert-butyl peroxide, 2,5-dimethyl-2,5-bis(tert-butyl peroxy) hexane, 2,5-dimethyl-2,5-di-tert-butyl peroxy-3-hexyne and dicumyl peroxide.

[0033] The co-crosslinking agent includes at least one of triallyl triisocyanate, triallyl tricyanurate, diallyl terephthalate, divinyl benzene, and a multifunctional acrylate.

[0034] The application also provides a prepreg, which includes a reinforcing material and the prepreg composition as described above attached to the reinforcing material.

[0035] The content of the magnetic substance in the reinforcing material is less than or equal to 2300 ppm, and the magnetic substance includes at least one of iron, cobalt, and nickel.

[0036] Specifically, in the reinforcing material, the content of iron is less than or equal to 2000 ppm, preferably less than 2000 ppm, further preferably less than 1000 ppm, and more preferably less than 500 ppm; the content of cobalt is less than or equal to 200 ppm, preferably less than 200 ppm, further preferably less than 100 ppm; and the content of nickel is less than or equal to 100 ppm, preferably less than 100 ppm, and further preferably less than 50 ppm.

[0037] Specifically, the method for preparing the prepreg includes the following steps:

[0038] S10, providing the prepreg composition as described above, dissolving the prepreg composition in a solvent to obtain a glue solution;

[0039] S11, placing the glue solution on a reinforcing material, removing the solvent to obtain a prepreg.

[0040] In step S10, the solvent includes at least one of xylene, toluene, acetone, butanone, and dimethylformamide. After the resin, the filler, and the auxiliary agent are mixed, the solvent is used to dilute to an appropriate viscosity, and the mixture is stirred and mixed to uniformly disperse the filler in the resin system to obtain the glue solution.

[0041] The application also provides a method for preparing a laminated board, which includes:

[0042] S20, providing the prepreg as described above;

[0043] S21, covering a metal foil on at least one surface of the prepreg and performing curing to make the prepreg react to form a dielectric layer to obtain a laminated board.

[0044] In step S20, the number of the prepregs can be multiple, including two, three, four, five, six, etc., and the number is determined according to actual use requirements. Multiple prepregs are stacked to form a prepreg layer.

[0045] In step S21, the temperature of the curing is 150-280°C, and the pressure is 10-80 Kg / cm 2 -80Kg / cm2 to make the resin in the prepreg cross-linking reaction to form a dielectric layer.

[0046] It can be understood that the metal foil is coated on one surface of the prepreg, or oppositely coated on two surfaces of the prepreg, preferably oppositely coated on two surfaces of the prepreg.

[0047] The present application also provides a laminate prepared by the above-mentioned method, comprising a dielectric layer and a metal foil coated on at least one surface of the dielectric layer.

[0048] Specifically, the content of the magnetic substance in the metal foil is less than or equal to 1500 ppm, and the magnetic substance comprises at least one of iron, cobalt and nickel.

[0049] Preferably, the metal foil is a copper foil, and the content of iron, cobalt and nickel in the copper foil is less than or equal to 500 ppm, preferably less than 500 ppm, and further preferably less than 300 ppm.

[0050] When the metal foil is a copper foil, the laminate is a copper clad laminate, which can effectively reduce the interference of passive intermodulation products caused by material nonlinearity, thereby improving the communication quality of the communication system.

[0051] Hereinafter, the prepreg composition, the prepreg, the laminate and the preparation method thereof will be further described through specific examples.

[0052] Table 1: Content of magnetic substance of each raw material in Example 1 to Example 8

[0053]

[0054] Table 2: Composition of the prepreg composition of Example 1 to Example 8 and the weight fraction thereof

[0055]

[0056]

[0057] The preparation method of Example 1 to Example 8 is as follows:

[0058] According to Table 1 and Table 2, the resin, the filler and the curing agent are mixed, and the solvent of xylene is added to adjust the viscosity to a suitable value, and then stirred and mixed uniformly to make the filler uniformly dispersed in the resin to prepare a glue solution. The first 1080 glass fiber cloth is impregnated with the above glue solution, and then dried to remove the solvent to prepare a tack-free prepreg.

[0059] Four prepregs were laminated to form a prepreg layer, 1 oz thickness copper foil was coated on two opposite surfaces of the prepreg layer, and the copper clad laminate was prepared by programmed temperature curing in a press with a curing pressure of 60 Kg / cm 2 , a curing temperature of 170℃ for 2h, and then a curing temperature of 270℃ for 1h.

[0060] The copper clad laminate was processed to a PCB by drilling, hole plugging, micro-etching, pre-impregnation, activation, acceleration, chemical copper and copper plating processes. The PCB was tested for PIM and dielectric, wherein the dielectric test was performed using a Rosenberger vector network analyzer, and the PIM test was performed using a Rosenberger AMPS 1900. The data are shown in Table 3.

[0061] Table 3: Data of Examples 1-8

[0062]

[0063]

[0064] As shown in Table 3, the lower the content of magnetic substances of iron, cobalt and nickel in the prepreg composition, the lower the loss and PIM of the substrate. As shown in Examples 1-4 and 5-8, the dielectric loss decreases with the decrease of the magnetic substances of the material. As shown in Examples 1, 4, 5, 8 and 2, 3, 6, 7, the average PIM of the substrate decreases significantly with the decrease of the magnetic substances of the material.

[0065] Table 4: Content of magnetic substances of each raw material in Comparative Examples 1-6

[0066]

[0067] Table 5: Composition of the prepreg composition of Comparative Examples 1-6 and the weight fraction of each component

[0068]

[0069]

[0070] The preparation method of the comparative examples is as follows:

[0071] According to Tables 4 and 5, the resin, filler and curing agent were mixed, and the viscosity was adjusted to a suitable value using xylene solvent. The mixture was stirred until the filler was uniformly dispersed in the resin to obtain a glue solution. The second 1080 glass fiber cloth was impregnated with the above glue solution, and then dried to remove the solvent to obtain a tack-free prepreg.

[0072] Four prepregs were laminated to form a prepreg layer, 1 oz thickness copper foils were coated on two opposite surfaces of the prepreg layer, and the prepreg layer was cured in a press at a programmed temperature, with a curing pressure of 60 Kg / cm 2 , a curing temperature of 170℃ for 2h, and then a curing temperature of 270℃ for 1h, to obtain a copper-clad plate.

[0073] The copper-clad plate was processed into a PCB through drilling, hole cleaning, micro-etching, pre-impregnation, activation, acceleration, chemical copper and copper thickening processes. The PCB was subjected to PIM testing and dielectric testing, wherein the dielectric testing was performed using a Rosenberger vector network analyzer, and the PIM testing was performed using a Rosenberger AMPS 1900. The data are shown in Table 6.

[0074] Table 6: Data of Comparative Example 1 to Comparative Example 6

[0075]

[0076] As can be seen from Table 3 and Table 6, the lower the content of magnetic substances of iron, cobalt and nickel in the prepreg composition and the reinforcing material, the lower the average PIM result of the PCB made therefrom, and the dielectric loss thereof is also improved. Therefore, the PIM performance of the PCB can be controlled by controlling the content of magnetic substances of iron, cobalt and nickel in each component, and the dielectric loss thereof can be further reduced.

[0077] Any technical features in the above-described embodiments can be combined, and for the sake of brevity, not all possible combinations of the technical features in the above-described embodiments are described, however, as long as the combinations of the technical features do not contradict each other, they should be considered within the scope of the present disclosure.

[0078] The above-described embodiments only express several embodiments of the present application, and the description is relatively specific and detailed, but it should not be understood as a limitation on the scope of the patent. It should be noted that for ordinary skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are within the scope of the present application. Therefore, the scope of protection of the present application should be subject to the appended claims.

Claims

1. A prepreg, characterized by, The prepreg composition attached to the reinforcing material includes a resin, a filler, and an additive, wherein the amount of the filler is 60-150 parts by weight based on 100 parts by weight of the resin, and the amount of the additive is 1-30 parts by weight based on 100 parts by weight of the resin. The content of the magnetic substance in the resin is less than or equal to 150 ppm. The content of the magnetic substance in the additive is less than or equal to 60 ppm. The content of iron, cobalt, and nickel in the resin is less than or equal to 50 ppm. The content of magnetic substance in the filler is less than or equal to 1150 ppm; the filler is composed of 20 parts by weight of the first filler and 40 parts by weight of the second filler, or composed of 40 parts by weight of the first filler and 110 parts by weight of the second filler, the first filler is D 50 hollow glass microspheres with a diameter of 25 μm, the content of iron in the first filler is 1000 ppm, the content of cobalt is 100 ppm, and the content of nickel element is 50 ppm, and the second filler is D 50 angular silicon with a diameter of 10 μm, the content of iron in the second filler is 100 ppm, the content of cobalt is 30 ppm, and the content of nickel element is 10 ppm; The content of iron, cobalt, and nickel in the additive is less than or equal to 20 ppm.

2. The prepreg according to claim 1, characterized by The content of iron in the reinforcing material is less than or equal to 2000 ppm, the content of cobalt is less than or equal to 200 ppm, and the content of nickel is less than or equal to 100 ppm.

3. The prepreg according to claim 1, wherein The prepreg composition attached to the reinforcing material includes a resin, a filler, and an additive, wherein the amount of the filler is 60-150 parts by weight based on 100 parts by weight of the resin, and the amount of the additive is 1-30 parts by weight based on 100 parts by weight of the resin.

4. The prepreg according to any one of claims 1 to 3, characterized by, The content of the magnetic substance in the resin is less than or equal to 150 ppm.

5. A method of producing a laminate board, characterized by The content of the magnetic substance in the additive is less than or equal to 60 ppm. The content of iron, cobalt, and nickel in the resin is less than or equal to 50 ppm. The content of iron, cobalt, and nickel in the additive is less than or equal to 20 ppm.

6. The method of producing a laminate according to claim 5, characterized by, The content of iron in the reinforcing material is less than or equal to 2000 ppm, the content of cobalt is less than or equal to 200 ppm, and the content of nickel is less than or equal to 100 ppm.

7. A laminate characterized by The prepreg composition attached to the reinforcing material includes a resin, a filler, and an additive, wherein the amount of the filler is 60-150 parts by weight based on 100 parts by weight of the resin, and the amount of the additive is 1-30 parts by weight based on 100 parts by weight of the resin.

8. The laminate of claim 7, wherein, The content of the magnetic substance in the resin is less than or equal to 150 ppm.

9. The laminate of claim 7, wherein, The content of the magnetic substance in the additive is less than or equal to 60 ppm. The content of iron, cobalt, and nickel in the resin is less than or equal to 50 ppm. The content of iron, cobalt, and nickel in the additive is less than or equal to 20 ppm. The content of iron in the reinforcing material is less than or equal to 2000 ppm, the content of cobalt is less than or equal to 200 ppm, and the content of nickel is less than or equal to 100 ppm.

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