WO2024007535A1

WO2024007535A1 - Fluorine-containing resin copper-clad laminate and multi-layer circuit board

Info

Publication number: WO2024007535A1
Application number: PCT/CN2022/138715
Authority: WO
Inventors: 柴颂刚; 刘潜发; 梁伟; 许永静
Original assignee: 广东生益科技股份有限公司
Priority date: 2022-07-05
Filing date: 2022-12-13
Publication date: 2024-01-11
Also published as: CN115071226B; CN115071226A

Abstract

Provided in the present invention are a fluorine-containing resin copper-clad laminate and a multi-layer circuit board. The fluorine-containing resin copper-clad laminate comprises copper foil, one or a combination of at least one prepreg layer of fluorine-containing resin fiberglass cloth and at least one resin film layer of fluorine-containing resin, and at least one prepreg layer of fluorine-containing resin non-woven fabric, the prepreg of the fluorine-containing resin non-woven fabric comprising fluorine-containing resin adhesive non-woven fabric and a fluorine-containing resin composition. The fluorine-containing resin copper-clad laminate in the present invention has an excellent dielectric property and a relatively low size expansion and shrinkage rate, can meet the requirements of a high-frequency electronic circuit substrate for comprehensive properties such as a low dielectric constant, low dielectric loss, low insertion loss, high reliability, and accordingly can serve as a circuit board to be applied to an electronic product.

Description

Fluorine-containing resin copper-clad laminate and multilayer circuit board

Technical field

The invention belongs to the technical field of laminates and relates to a fluorine-containing resin copper-clad laminate and a multi-layer circuit board.

Background technique

As one of the key basic materials in the electronic communications and information industry, copper clad laminates are widely used in mobile phones, computers, vending machines, communication base stations, satellites, wearable devices, driverless cars, drones and intelligent robots. Due to its excellent properties such as low dielectric loss, high thermal stability and chemical stability, fluorine-containing resins represented by polytetrafluoroethylene (PTFE) are ideal base materials for preparing copper-clad laminates. Since the 1950s, researchers have gradually improved the manufacturing process of PTFE-based copper-clad laminates through continuous optimization of formulas and parameters.

The polymer chain of fluororesin is relatively flexible, and inorganic materials usually need to be introduced to improve the mechanical strength of fluororesin-based copper-clad laminates. Adding inorganic fillers, using woven glass fiber cloth and using random glass fiber mat (also known as non-woven fabric, fiberglass paper) are three common ways in the industry to improve the mechanical strength of fluorine-containing resin. Among them, the fluorine-containing membrane is prepared by adding inorganic fillers to fluorine-containing resin. It is modified with high-purity and low-loss ceramic fillers and surface treatment. The membrane has the best electrical properties and the best dielectric loss. The disadvantages are the poor mechanical strength and size of the membrane. Poor stability. Fluorine-containing varnish cloth prepared by impregnating woven glass fiber cloth with fluorine-containing resin has the best mechanical strength and good dimensional stability. The disadvantages are the poor dielectric loss caused by glass fiber and the dielectric constant at different positions of the material caused by the woven structure. The uniformity is poor. Prepregs are prepared by impregnating traditional non-woven fabrics with fluorine-containing resin. Traditional non-woven fabrics generally use epoxy binders, acrylate binders, melamine binders or polyvinyl alcohol binders. , the large dielectric loss of these binders leads to large dielectric loss of the prepreg; at the same time, because the random glass fibers in the non-woven fabric have no directionality, the dielectric constant at different locations of the prepreg has good uniformity. The properties of these three structures of fluorine-containing resin materials have their own characteristics.

Therefore, developing a fluororesin copper-clad laminate with excellent dielectric properties, mechanical strength and low dimensional expansion and contraction is an urgent problem in this field.

Contents of the invention

In view of the shortcomings of the existing technology, the purpose of the present invention is to provide a fluorine-containing resin copper-clad laminate and a multi-layer circuit board. The fluorine-containing resin copper-clad laminate has excellent dielectric properties, mechanical strength and low dimensional expansion and contraction, and can meet the requirements of High-frequency electronic circuit substrates have comprehensive performance requirements such as low dielectric constant, low dielectric loss, low insertion loss, and high reliability, so they can be used as circuit boards in electronic products.

To achieve this goal, the present invention adopts the following technical solutions:

In one aspect, the present invention provides a fluororesin copper-clad laminate, which includes copper foil, at least one prepreg layer of fluororesin glass fiber cloth, and at least one fluororesin resin film. One or a combination of both layers, and at least one prepreg layer of fluororesin nonwoven fabric, the prepreg of fluororesin nonwoven fabric includes fluororesin adhesive nonwoven fabric and Fluorine-containing resin composition.

In the present invention, the copper-clad laminate includes a prepreg layer of fluororesin non-woven fabric, and one or both of a prepreg layer of fluororesin glass fiber cloth and a resin film layer of fluororesin. That is to say, the copper-clad laminate may include a prepreg layer of fluororesin non-woven fabric and a prepreg layer of fluororesin fiberglass cloth; the copper-clad laminate may also include a prepreg layer of fluororesin non-woven fabric and fluorine-containing fiberglass fabric. The resin film layer of the resin; the copper-clad laminate may also include a prepreg layer of fluororesin non-woven fabric, a prepreg layer of fluororesin fiberglass cloth and a resin film layer of fluororesin. By using at least one prepreg layer of fluororesin nonwoven fabric and at least one prepreg layer of fluororesin glass fiber cloth and at least one resin film layer of fluororesin, or The combination of the two and copper foil forms a copper-clad laminate, which makes the dielectric constant and dielectric loss of the copper-clad laminate low, and has low dimensional expansion and contraction.

In the present invention, the Dk dielectric constant of the fluorine-containing resin copper-clad laminate at a frequency of 10 GHz is 2.2-10.2, and the dielectric loss tangent Df is less than 0.003.

Preferably, the fluorine-containing resin adhesive nonwoven fabric is composed of inorganic fibers and a binder, and the binder is a fluorine-containing resin emulsion. The non-woven fabric composed of such a binder and inorganic fibers has low dielectric loss, good uniformity, consistent thickness, consistent fiber distribution in all directions, and higher tensile strength than the resin film layer of fluororesin.

Preferably, the weight percentage of inorganic fibers in the fluorine-containing resin adhesive non-woven fabric is 60-95% (for example, 60%, 62%, 65%, 68%, 70%, 73%, 75%, 78%, 80 %, 83%, 85%, 88%, 90%, 93% or 95%), the weight percentage of the binder is 5%-40% (such as 5%, 8%, 10%, 15%, 18%, 20%, 23%, 25%, 28%, 30%, 33%, 35%, 38% or 40%). In the present invention, if the weight percentage of the binder is too low, the binder will not be able to continuously form a film, resulting in low strength of the non-woven fabric. If the weight percent of the binder is too high, there will be many voids inside the non-woven fabric. , there are many defects, resulting in low strength of the non-woven fabric, which in turn affects the dielectric loss and adhesion.

Preferably, the fluorine-containing resin emulsion is selected from polytetrafluoroethylene emulsion, polyperfluoroethylene-propylene emulsion, polyvinylidene fluoride emulsion, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer emulsion, ethylene-tetrafluoroethylene Any one or a combination of at least two of copolymer emulsions, polychlorotrifluoroethylene emulsions or ethylene-chlorotrifluoroethylene copolymer emulsions.

Preferably, the solid content in the fluorine-containing resin emulsion is 30-70%, such as 30%, 35%, 38%, 40%, 45%, 50%, 55%, 60%, 65% or 70%.

Preferably, the particle size of the fluorine-containing resin in the fluorine-containing resin emulsion is 0.10 μm to 0.40 μm.

In this article, the particle size of the fluororesin emulsion was measured using the laser diffraction method, and the testing instrument was a Malvern laser particle size analyzer, model MS3000. In this article, the dielectric constant and dielectric loss are tested using the SPDR (split post dielectric resonator) method with a frequency of 10GHz.

Preferably, the binder further includes any one or a combination of at least two of defoaming agents, dispersants or thickeners.

Preferably, the inorganic fiber is selected from E glass fiber, NE glass fiber, L glass fiber, quartz fiber, alumina fiber, boron nitride fiber, silicon carbide fiber, zinc oxide fiber, magnesium oxide fiber, silicon nitride fiber, Boron carbide fiber, aluminum nitride fiber, aluminum oxide whisker, boron nitride whisker, silicon carbide whisker, zinc oxide whisker, magnesium oxide whisker, silicon nitride whisker, boron carbide whisker or aluminum nitride crystal Any one or a combination of at least two of them.

Preferably, the average diameter of the inorganic fiber is less than 13 microns, such as 12 microns, 9 microns, 8 microns, 7 microns, 6 microns, 5 microns, 4 microns, 3 microns, 2 microns or 1 micron, etc., preferably 0.5-5 microns. .

Preferably, the average length of the inorganic fiber is 1-100 mm, such as 100 mm, 90 mm, 80 mm, 70 mm, 60 mm, 50 mm, 40 mm, 30 mm, 20 mm, 10 mm, 5 mm, preferably 1-10mm.

The average diameter and average length of the inorganic fibers in the present invention are obtained by observation and testing using a scanning electron microscope.

Preferably, the fluororesin adhesive nonwoven fabric is surface-treated.

Preferably, the adhesive can be dissolved and diluted to a suitable viscosity by adding a solvent as needed, so that the fibers and the adhesive are evenly dispersed. Examples of the solvent include deionized water, etc. The solvent will evaporate during the drying and sintering process of non-woven fabric preparation.

Preferably, the unit weight (also known as unit area mass) of the fluororesin adhesive non-woven fabric is 20-200 g/m2, such as 20 g/m2, 25 g/m2, 30 g/m2, 35 g/m2 g/m2, 40 g/m2, 50 g/m2, 60 g/m2, 80 g/m2, 100 g/m2, 120 g/m2, 150 g/m2, 180 g/m2 Square meter or 200 g/square meter, preferably 20-100 g/square meter.

In the present invention, the fluorine-containing resin adhesive nonwoven fabric can be prepared by the following method: mixing inorganic fibers and binders, impregnating them, forming them by papermaking, drying, and sintering to obtain the low dielectric loss nonwoven fabrics. cloth.

In the present invention, the laboratory prepared non-woven fabrics with different unit weights by adjusting the weights of inorganic fibers and adhesives. Industrial production produces non-woven fabrics of different unit weights by adjusting the solubility and speed of inorganic fibers and adhesives, solvents.

Preferably, the impregnation time is 40 to 50 minutes, such as 40 minutes, 43 minutes, 45 minutes, 48 minutes or 50 minutes.

Preferably, the drying temperature is 120-150°C, such as 120°C, 125°C, 130°C, 135°C, 140°C, 145°C or 150°C, and the drying time is 1-30min, such as 5min, 8min , 10min, 15min, 20min, 25min or 30min.

Preferably, the sintering temperature is 250°C-350°C, such as 260°C, 270°C, 290°C, 300°C, 320°C or 340°C, and the sintering time is 1 to 20min, such as 1min, 3min, 5min, 8min , 10min, 13min, 15min, 18min or 20min.

Preferably, the prepreg of the fluororesin nonwoven fabric includes a fluororesin adhesive nonwoven fabric and a fluororesin composition attached thereto by impregnation.

Preferably, the prepreg of fluorine-containing resin glass fiber cloth includes glass fiber cloth and a fluorine-containing resin composition.

Preferably, the fluorine-containing resin resin film is prepared by coating a fluorine-containing resin composition on a release material.

Preferably, the fluororesin compositions in the prepreg of the fluororesin nonwoven fabric, the prepreg of the fluororesin glass fiber cloth, and the fluororesin resin film each independently include a fluororesin emulsion.

Preferably, the fluororesin emulsion in the prepreg of the fluororesin nonwoven fabric, the prepreg of the fluororesin glass fiber cloth, and the fluororesin resin film are each independently selected from polytetrafluoroethylene. emulsion, polyperfluoroethylene-propylene emulsion, polyvinylidene fluoride emulsion, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer emulsion, ethylene-tetrafluoroethylene copolymer emulsion, polychlorotrifluoroethylene emulsion or ethylene-trifluoroethylene Any one or a combination of at least two of vinyl chloride copolymer emulsions.

Preferably, the fluororesin compositions in the prepreg of fluororesin nonwoven fabric, the prepreg of fluororesin glass fiber cloth, and the fluororesin resin film each independently further include a filler selected from the group consisting of: Silicon oxide, hollow microspheres, titanium dioxide, boron nitride, aluminum nitride, silicon carbide, aluminum oxide, barium titanate, strontium titanate, magnesium titanate, calcium titanate, barium strontium titanate, barium perovskite titanate, titanium Any one or a combination of at least two of lead acid, lead zirconate titanate, chopped glass fiber powder or chopped quartz fiber powder.

Preferably, the fluororesin compositions in the prepreg of fluororesin nonwoven fabric, the prepreg of fluororesin glass fiber cloth, and the fluororesin resin film each independently further include a coupling agent.

Preferably, the fluororesin composition in the prepreg of fluororesin nonwoven fabric, the prepreg of fluororesin glass fiber cloth, and the resin film of fluororesin each independently further includes a surfactant.

As a preferred technical solution, the fluororesin copper-clad laminate includes the following layers combined from top to bottom:

The first copper foil layer;

At least one first resin film layer of fluorine-containing resin;

At least one prepreg layer of fluororesin nonwoven fabric;

At least one second resin film layer of fluororesin;

Second copper foil layer.

In this preferred structure, the resin film layer of fluororesin is in contact with the copper foil layer, and a prepreg layer of fluororesin non-woven fabric is placed in the middle. This structure prevents the copper foil from directly contacting the inorganic fibers, thereby maintaining a high of adhesion.

Preferably, the single layer thickness of the first resin film layer of fluorine-containing resin and the second resin film layer of fluorine-containing resin is independently 20-200 μm, such as 20 μm, 30 μm, 50 μm, 80 μm, 100 μm, 130 μm, 150 μm, 180μm or 200μm.

Preferably, the single layer thickness of the prepreg layer of the fluororesin nonwoven fabric is 100-2000 μm, such as 100 μm, 150 μm, 200 μm, 300 μm, 500 μm, 800 μm, 1000 μm, 1300 μm, 1500 μm, 1800 μm or 2000 μm.

As another preferred technical solution, the fluororesin copper-clad laminate includes the following layers combined from top to bottom:

The first copper foil layer;

At least one prepreg layer of the first fluororesin nonwoven fabric;

At least one prepreg layer of fluororesin fiberglass cloth;

At least one second prepreg layer of fluororesin nonwoven fabric;

Second copper foil layer.

In this preferred structure, the prepreg layer of fluororesin non-woven fabric is in contact with the copper foil layer, and the prepreg layer of fluororesin glass fiber cloth is placed in the middle. This structure has a glass fiber board prepreg layer in the middle. , making the copper-clad laminate have excellent dimensional stability; at the same time, the prepreg layer of the outer layer of fluorine-containing resin non-woven fabric has good dielectric constant uniformity, so that the copper-clad laminate has a uniform dielectric constant.

In this preferred structure, the single layer thicknesses of the prepreg layer of the first fluororesin nonwoven fabric and the prepreg layer of the second fluororesin nonwoven fabric are independently 100-2000 microns, for example 100 micron, 150 micron, 200 micron, 300 micron, 500 micron, 800 micron, 1000 micron, 1300 micron, 1500 micron, 1800 micron or 2000 micron.

In this preferred structure, the single layer thickness of the prepreg layer of the fluororesin glass fiber cloth is 30-300 microns, such as 30 microns, 50 microns, 80 microns, 100 microns, 150 microns, 200 microns, 250 micron or 300 micron.

On the other hand, the present invention provides a multilayer circuit board, including the fluorine-containing resin copper-clad laminate as described above.

Compared with the existing technology, the present invention has the following beneficial effects:

The fluorine-containing resin copper-clad laminate of the present invention has excellent dielectric properties and low dimensional expansion and contraction ratio, and can meet the comprehensive requirements of high-frequency electronic circuit substrates such as low dielectric constant, low dielectric loss, low insertion loss, and high reliability. performance requirements, so it can be used as a circuit board in electronic products.

Detailed ways

The technical solution of the present invention will be further described below through specific implementations. Those skilled in the art should understand that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

The experimental materials used in the examples and comparative examples of the present invention are as follows:

Nonwoven fabric, prepared from epoxy binder and E-glass fiber with average diameter of 13 μm, Shaanxi Huate.

Nonwoven fabric, prepared from acrylic binder and E-glass fiber with an average diameter of 13 μm, Shaanxi Huate.

Nonwoven fabric, prepared from melamine binder and E-glass fiber with an average diameter of 13 μm, Shaanxi Huate.

Preparation Example 1 Fluorine-containing resin composition configuration

45 parts by weight of polytetrafluoroethylene emulsion (PTFE emulsion, particle size 0.25 μm, solid content 55%, D210C from Daikin Company of Japan), add 25 parts by weight of silica (average particle size 10 μm, purchased from Jiangsu Lirui) , stir and mix for 2 hours to obtain fluororesin composition A-1.

50 parts by weight of polytetrafluoroethylene emulsion (PTFE emulsion, particle size 0.25 μm, solid content 55%, D210C from Daikin Company of Japan) and 5 parts by weight of FEP resin emulsion (solid content 50wt%, produced by Daikin Company of Japan, brand: ND-110) and 20 parts of boron nitride (average particle size 10 μm, purchased from Anhui Yishitong), 3 parts of titanium dioxide (average particle size 10 μm, purchased from Wuxi Longao) and 15 parts of silica (average particle size 10 μm) (purchased from Jiangsu Lirui), stir and mix for 2 hours to obtain fluororesin composition A-2.

Preparation Example 2 Preparation of fluorine-containing resin nonwoven fabric

Inorganic fibers, adhesives and solvents are mixed and impregnated, placed in a circular standard sheet machine (Kumagaya Riki Kogyo Co., Ltd), fully stirred and filtered, formed into paper, dried and sintered to obtain a circular sheet with a diameter of 80mm. shaped non-woven fabric. Non-woven fabrics with different unit weights are produced by adjusting the weight of inorganic fibers and adhesives. details as follows:

Mix 95 parts by weight of E glass fiber (average diameter 5 microns, China Jushi Co., Ltd.), 5 parts by weight of FEP resin emulsion (solid content 50wt%, produced by Daikin Corporation of Japan, brand: ND-110) and an appropriate amount of deionized water Dip for 45 minutes, undergo paper making, dry in a 150°C oven, and then sinter in a high-temperature oven at 270°C for 15 minutes. After cooling, a non-woven fabric A with a unit weight of 20 g/m2 is obtained.

Soak 70 parts by weight of quartz fiber (average diameter 0.5μm and 5μm, weight ratio 1:4, China Shenjiu), 30 parts by weight of ETFE emulsion (solid content 50wt%, sample from Dongyue, Shandong) and an appropriate amount of deionized water for 45 minutes , after papermaking, drying in a 140°C oven, and then sintering in a high-temperature oven at 280°C for 25 minutes, taking it out and cooling to obtain non-woven fabric B with a unit weight of 75 g/m2.

Preparation Example 3 Preparation of fluorine-containing resin nonwoven prepreg

Non-woven fabric A was impregnated with fluorine-containing resin composition A-1, dried in a 100°C oven for 1 hour, and sintered in a 360°C oven for 0.5 hours. By adjusting the number of impregnations, 130 μm and 150 μm thick fluorine-containing resin nonwovens were obtained. Fabric prepreg A.

Non-woven fabric B was impregnated with fluorine-containing resin composition A-2, dried in an oven at 100°C for 1 hour, and sintered in an oven at 360°C for 0.5 hours. By adjusting the number of impregnations, fluorine-containing resin nonwovens with thicknesses of 130 μm and 150 μm were obtained respectively. Fabric prepreg B.

Preparation Example 4 Preparation of Resin Film of Fluorine-Containing Resin

Coat the fluorine-containing resin composition A-1 on a steel plate with a clean and smooth surface, dry it in a vacuum oven at 100°C for 1 hour to remove moisture, bake it at 260°C for 1 hour to remove the additives, and bake it at 350°C for 10 minutes. After cooling, the filler-containing resin film is peeled off from the steel plate, and by adjusting different coating gaps, resin films A of fluorine-containing resin with thicknesses of 50 μm, 100 μm, and 150 μm are obtained.

Coat the fluorine-containing resin composition A-2 on a steel plate with a clean and smooth surface, dry it in a vacuum oven at 100°C for 1 hour to remove moisture, bake it at 260°C for 1 hour to remove the additives, and bake it at 350°C for 10 minutes. After cooling, the filler-containing resin film was peeled off from the steel plate, and by adjusting different coating gaps, fluorine-containing resin resin films B with thicknesses of 50 μm, 100 μm, and 150 μm were obtained.

Preparation Example 5 Preparation of fluororesin woven glass fiber paint cloth

The method includes the following steps:

The glass fiber cloth is impregnated with the fluorine-containing resin composition A-1, dried in a 100°C oven for 1 hour, and sintered in a 360°C oven for 0.5 hours. By adjusting the coating gap, a 50 μm thick fluorine-containing resin woven glass fiber paint cloth A is obtained;

The glass fiber cloth is impregnated with the fluorine-containing resin composition A-2, dried in a 100°C oven for 1 hour, and sintered in a 360°C oven for 0.5 hours. By adjusting the coating gap, a 50 μm-thick fluorine-containing resin woven glass fiber paint cloth B is obtained;

Preparation Comparative Example 1

The epoxy binder non-woven fabric (prepared from the epoxy binder and E-glass fiber with an average diameter of 13 μm) is impregnated with the fluororesin composition A-1, dried in a 100°C oven for 1 hour, and sintered in a 360°C oven After 0.5h, by adjusting the coating gap, a prepreg with a thickness of 130 μm was obtained.

Preparation Comparative Example 2

The difference from Preparation Comparative Example 1 is that the non-woven fabric with epoxy adhesive was replaced with the non-woven fabric with acrylate adhesive, and the rest are exactly the same.

Preparation Comparative Example 3

The difference from Preparation Comparative Example 1 is that the non-woven fabric with epoxy binder was replaced with non-woven fabric with melamine binder, and the rest are exactly the same.

Example 1

The fluororesin copper-clad laminate provided in this embodiment includes the following layers combined from top to bottom:

1 piece of 1OZ copper foil layer, HVLP, Jiangxi Copper;

1 fluororesin-containing resin film layer A, with a thickness of 50 μm;

1 sheet of prepreg A of fluororesin nonwoven fabric, thickness 150μm;

1 fluororesin-containing resin film layer A, with a thickness of 50 μm;

1 piece of 1OZ copper foil layer, HVLP, Jiangxi Copper.

The laminated structure was put into a press for solidification, applying a pressure of about 400 PSI, a maximum temperature of 380°C, a retention time of 90 minutes, and laminating to obtain the copper-clad laminate.

Example 2

One piece of fluororesin copper-clad laminate with 1OZ copper foil layer, HVLP, Jiangxi Copper;

1 fluororesin resin film layer B, thickness 100μm;

2 prepreg layers B of fluororesin non-woven fabric, single layer thickness 130μm;

1 fluororesin resin film layer B, thickness 100μm;

1 piece of 1OZ copper foil layer, HVLP, Jiangxi Copper.

Example 3

The fluorine-containing resin copper-clad laminate provided in this embodiment includes the following layers combined together from top to bottom: fluorine-containing resin copper-clad laminate

1 piece of 1OZ copper foil layer, HVLP, Jiangxi Copper;

2 sheets of fluorine-containing resin film layer A, with a single layer thickness of 150 μm;

1 prepreg layer B of fluororesin non-woven fabric, thickness 130μm;

1 piece of 1OZ copper foil layer, HVLP, Jiangxi Copper.

Example 4

1 prepreg layer A of fluororesin nonwoven fabric, thickness 130μm;

1 piece of fluororesin woven glass fiber varnish cloth A, thickness 50μm;

1 prepreg layer A of fluororesin nonwoven fabric, thickness 130μm;

1 piece of 1OZ copper foil layer, HVLP, Jiangxi Copper.

Example 5

2 sheets of fluororesin woven glass fiber varnish B, single layer thickness is 50μm;

1 piece of 1OZ copper foil layer, HVLP, Jiangxi Copper.

Example 6

1 piece of 1OZ copper foil layer, HVLP, Jiangxi Copper;

1 fluororesin-containing resin film layer A, with a single layer thickness of 150 μm;

1 prepreg layer B of fluororesin non-woven fabric, thickness 130μm;

1 piece of fluororesin woven glass fiber varnish A, single layer thickness is 50μm;

1 prepreg layer B of fluororesin non-woven fabric, thickness 130μm;

1 piece of 1OZ copper foil layer, HVLP, Jiangxi Copper.

Comparative example 1

The fluororesin copper-clad laminate provided in this comparative example includes the following layers combined from top to bottom:

1 piece of 1OZ copper foil layer, HVLP, Jiangxi Copper;

Three prepreg layers were prepared in Comparative Example 1, with a single layer thickness of 130 μm;

1 piece of 1OZ copper foil layer, HVLP, Jiangxi Copper.

Comparative example 2

The PTFE copper-clad laminate provided in this comparative example includes the following layers combined from top to bottom:

1 piece of 1OZ copper foil layer, HVLP, Jiangxi Copper;

3 sheets of fluororesin woven glass fiber varnish A, single layer thickness is 50μm;

1 piece of 1OZ copper foil layer, HVLP, Jiangxi Copper.

Comparative example 3

1 piece of 1OZ copper foil layer, HVLP, Jiangxi Copper;

5 sheets of fluororesin resin film layer A, with a single layer thickness of 50 μm;

1 piece of 1OZ copper foil layer, HVLP, Jiangxi Copper.

Comparative example 4

The difference from Example 1 is that the prepreg layer of one fluororesin nonwoven fabric in Example 1 is replaced with the prepreg prepared in Comparative Example 1, and the rest is the same as Example 1.

Comparative example 5

The difference from Example 1 is that the prepreg layer of one fluororesin nonwoven fabric in Example 1 was replaced with the prepreg prepared in Comparative Example 2, and the rest was the same as Example 1.

Comparative example 6

The difference from Example 1 is that the prepreg layer of one fluororesin nonwoven fabric in Example 1 was replaced with the prepreg prepared in Comparative Example 3, and the rest was the same as Example 1.

Comparative example 7

The difference from Example 4 is that the prepreg layers of the fluororesin nonwoven fabric in Example 4 were replaced with the prepreg prepared in Comparative Example 1, and the rest was the same as Example 1.

Comparative example 8

The difference from Example 4 is that the prepreg layers of the fluororesin nonwoven fabric in Example 4 were replaced with the prepreg prepared in Comparative Example 2, and the rest was the same as Example 1.

Comparative example 9

The difference from Example 4 is that the prepreg layers of the fluororesin nonwoven fabric in Example 4 were replaced with the prepreg prepared in Comparative Example 3, and the rest was the same as Example 1.

Performance Testing

For the copper-clad laminates prepared in the above examples and comparative examples, the following performance tests were performed:

(1) Dk and Df test: SPDR (split post dielectric resonator) method is used for testing; the test condition is state A and the frequency is 10GHz;

(2) Dimensional stability: Use IPC-TM-650 2.4.39 to test the dimensional stability in the X/Y direction.

The specific test results are shown in Table 1:

Table 1

It can be seen from Examples 1 to 6 that the dielectric constant of the copper-clad laminate containing the non-woven prepreg is between 3.06 and 3.15, the dielectric loss is <0.002, and the dimensional stability is <1500ppm, taking into account both dielectric loss and Dimensional stability. It can be seen from Comparative Example 1 that the dielectric loss of the board made of impregnated non-woven fabrics prepared entirely with epoxy adhesive is high. According to Comparative Example 2, all fluorine-containing resin woven glass fiber varnishes are used, and the dielectric loss of the board is higher; according to Comparative Example 3, all fluorine-containing resin films are used, and the dimensional stability of the board is the worst.

Comparative Examples 4-6 use non-woven fabrics without fluorine-containing resin adhesive. Compared with Example 1, the dielectric loss and dielectric constant of the board are higher.

Comparative Examples 7-9 use non-woven fabrics without fluorine-containing resin adhesive. Compared with Example 4, the dielectric loss and dielectric constant of the board are higher.

In summary, the copper-clad laminate structure of the present invention has both excellent dielectric properties and low dimensional expansion rate, and can be used in the field of high-frequency communications.

The applicant declares that the present invention is illustrated by the above-mentioned embodiments, but the present invention is not limited to the above-mentioned embodiments, that is, it does not mean that the present invention must rely on the above-mentioned embodiments to be implemented. Those skilled in the art should understand that any improvements to the present invention, equivalent replacement of raw materials of the product of the present invention, addition of auxiliary ingredients, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

A fluororesin copper-clad laminate, characterized in that the fluororesin copper-clad laminate includes copper foil, and at least one prepreg layer of fluororesin glass fiber cloth and at least one resin film layer of fluororesin. One or a combination of two of them, and at least one prepreg layer of fluorine-containing resin non-woven fabric, the prepreg of fluorine-containing resin non-woven fabric includes fluorine-containing resin adhesive non-woven fabric and fluorine-containing resin non-woven fabric. Resin composition.
The fluorine-containing resin copper-clad laminate according to claim 1, wherein the Dk dielectric constant of the fluorine-containing resin copper-clad laminate at a frequency of 10 GHz is 2.2-10.2, and the dielectric loss tangent Df is less than 0.003.
The fluororesin copper-clad laminate according to claim 1 or 2, characterized in that the fluororesin adhesive non-woven fabric is composed of inorganic fibers and a binder, and the binder is a fluororesin emulsion;

Preferably, the weight percentage of inorganic fibers in the fluororesin adhesive non-woven fabric is 60-95%, and the weight percentage of the binder is 5%-40%;

Preferably, the fluorine-containing resin emulsion is selected from polytetrafluoroethylene emulsion, polyperfluoroethylene-propylene emulsion, polyvinylidene fluoride emulsion, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer emulsion, ethylene-tetrafluoroethylene Any one or a combination of at least two of copolymer emulsions, polychlorotrifluoroethylene emulsions or ethylene-chlorotrifluoroethylene copolymer emulsions;

Preferably, the solid content in the fluorine-containing resin emulsion is 30-70%;

Preferably, the binder further includes any one or a combination of at least two of defoaming agents, dispersants or thickeners.
The fluororesin copper-clad laminate according to any one of claims 1 to 3, characterized in that the inorganic fiber is selected from the group consisting of E glass fiber, NE glass fiber, L glass fiber, quartz fiber, alumina fiber, nitride fiber, Boron fiber, silicon carbide fiber, zinc oxide fiber, magnesium oxide fiber, silicon nitride fiber, boron carbide fiber, aluminum nitride fiber, aluminum oxide whisker, boron nitride whisker, silicon carbide whisker, zinc oxide whisker, Any one or a combination of at least two of magnesium oxide whiskers, silicon nitride whiskers, boron carbide whiskers or aluminum nitride whiskers;

Preferably, the average diameter of the inorganic fibers is less than 13 microns, preferably 0.5-5 microns;

Preferably, the average length of the inorganic fiber is 1-100 mm, preferably 1-10 mm;

Preferably, the fluororesin adhesive non-woven fabric has undergone surface treatment;

Preferably, the unit weight of the fluororesin adhesive non-woven fabric is 20-200 grams/square meter.
The fluorine-containing resin copper-clad laminate according to any one of claims 1 to 4, characterized in that the prepreg of the fluorine-containing resin glass fiber cloth includes glass fiber cloth and a fluorine-containing resin composition.
The fluorine-containing resin copper-clad laminate according to any one of claims 1 to 5, characterized in that the fluorine-containing resin resin film is prepared by coating a fluorine-containing resin composition on a release material.
The fluorine-containing resin copper-clad laminate according to any one of claims 1 to 6, characterized in that, the prepreg of the fluorine-containing resin non-woven fabric, the prepreg of the fluorine-containing resin glass fiber cloth and the fluorine-containing resin The fluorine-containing resin composition in the resin film each independently includes a fluorine-containing resin emulsion;

Preferably, the fluororesin emulsion in the prepreg of the fluororesin nonwoven fabric, the prepreg of the fluororesin glass fiber cloth, and the fluororesin resin film are each independently selected from polytetrafluoroethylene. emulsion, polyperfluoroethylene-propylene emulsion, polyvinylidene fluoride emulsion, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer emulsion, ethylene-tetrafluoroethylene copolymer emulsion, polychlorotrifluoroethylene emulsion or ethylene-trifluoroethylene Any one or a combination of at least two of vinyl chloride copolymer emulsions;

Preferably, the fluorine-containing resin composition further includes fillers selected from the group consisting of silica, hollow microspheres, titanium dioxide, boron nitride, aluminum nitride, silicon carbide, alumina, barium titanate, strontium titanate, and titanate. Any one or a combination of at least two of magnesium, calcium titanate, barium strontium titanate, barium perovskite, lead titanate, lead zirconate titanate, chopped glass fiber powder or chopped quartz fiber powder;

Preferably, the fluorine-containing resin composition further includes a coupling agent;

Preferably, the fluorine-containing resin composition further includes a surfactant.
The fluorine-containing resin copper-clad laminate according to any one of claims 1 to 7, characterized in that the fluorine-containing resin copper-clad laminate includes the following layers combined from top to bottom:

The first copper foil layer;

At least one first resin film layer of fluorine-containing resin;

At least one prepreg layer of fluororesin nonwoven fabric;

At least one second resin film layer of fluororesin;

second copper foil layer;

Preferably, the single layer thicknesses of the first resin film layer of fluorine-containing resin and the second resin film layer of fluorine-containing resin are independently 20-200 μm;

Preferably, the single-layer thickness of the prepreg layer of the fluororesin nonwoven fabric is 100-2000 μm.
The fluorine-containing resin copper-clad laminate according to any one of claims 1 to 7, characterized in that the fluorine-containing resin copper-clad laminate includes the following layers combined from top to bottom:

The first copper foil layer;

At least one prepreg layer of the first fluororesin nonwoven fabric;

At least one prepreg layer of fluororesin fiberglass cloth;

At least one second prepreg layer of fluororesin nonwoven fabric;

second copper foil layer;

Preferably, the single layer thicknesses of the prepreg layer of the first fluororesin nonwoven fabric and the prepreg layer of the second fluororesin nonwoven fabric are independently 100-2000 μm;

Preferably, the single-layer thickness of the prepreg layer of the fluororesin glass fiber cloth is 30-300 μm.
A multilayer circuit board, including the fluorine-containing resin copper-clad laminate according to any one of claims 1-9.