CEM-1 copper-clad laminate and preparation method thereof

Abstract

The invention provides a CEM-1 copper clad laminate and a preparation method thereof, and the preparation method comprises the following steps: (1) mixing a reaction type water-based phosphorus-containing epoxy resin and a water-based curing agent to obtain a first glue solution; (2) impregnating wood pulp fiber paper in the first glue solution, and drying to obtain a prepreg; (3) mixing epoxy resin, a curing agent, a flame-retardant filler and an organic solvent to obtain a second glue solution; (4) impregnating the prepreg obtained in the step (2) in a second glue solution, and drying to obtain a bonding sheet; and (5) overlapping at least two bonding sheets together to serve as a core material, paving a surface material prepreg on each of two sides of the core material, covering a copper foil on one side, far away from the core material, of the surface material prepreg, and performing hot pressing to obtain the CEM-1 copper foil-coated laminated board. The CEM-1 copper clad laminate prepared by the preparation method provided by the invention not only has better flame retardance, but also has better heat resistance and processability.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of copper-clad plate, and relates to a CEM-1 copper-clad foil laminated plate and a preparation method thereof. BACKGROUND

[0002] The CEM-1 copper-clad foil laminated plate uses electronic-grade glass fiber cloth and bleached wood pulp paper as reinforcing materials, respectively soaks in a resin composition for the copper-clad foil laminated plate to form a surface material with the electronic-grade glass fiber cloth as the reinforcing material and a core material with the bleached wood pulp paper as the reinforcing material, and is covered with a copper foil and formed through hot pressing.

[0003] The CEM-1 copper-clad foil laminated plate has better performance than a paper-based copper-clad foil laminated plate and lower cost than a glass fiber cloth-based copper-clad foil laminated plate, and has good competitiveness in mechanical properties, electrical properties, cost and processability. In recent years, with the development of lead-free, halogen-free and intelligent terminal products, higher requirements are put forward for the heat resistance, flame retardance and punching property of halogen-free CEM-1 copper-clad foil laminated plates.

[0004] At present, the existing technology generally adds an additive flame retardant to improve the flame retardance of the CEM-1 copper-clad foil laminated plate, but the heat resistance and processability (for example, punching processability) of the CEM-1 copper-clad foil laminated plate prepared by this method will be poor.

[0005] Therefore, in the field, it is desirable to develop a preparation method of a CEM-1 copper-clad foil laminated plate, and the CEM-1 copper-clad foil laminated plate prepared by the method has good flame retardance, heat resistance and processability. SUMMARY

[0006] In view of the deficiencies of the prior art, the present application aims to provide a CEM-1 copper-clad foil laminated plate and a preparation method thereof. The present application uses a reactive water-based phosphorus-containing epoxy resin and a water-based curing agent, which can be cured by reaction, and directly performs flame retardant treatment on wood pulp fiber paper, thereby improving the flame retardant efficiency, reducing the amount of flame retardant, avoiding the problem of adding a large amount of flame retardant in the traditional way, and solving the problems of poor heat resistance and processability of the existing halogen-free CEM-1 copper-clad foil laminated plate.

[0007] To achieve the object of the present application, the following technical solutions are adopted:

[0008] In a first aspect, the present application provides a preparation method of a CEM-1 copper-clad foil laminated plate, which comprises the following steps:

[0009] (1) mixing a reactive water-based phosphorus-containing epoxy resin and a water-based curing agent to obtain a first glue solution;

[0010] (2) Impregnate the wood pulp fiber paper in the first adhesive solution and dry it to obtain the prepreg;

[0011] (3) Mix epoxy resin, curing agent, flame retardant filler and organic solvent to obtain the second adhesive solution;

[0012] (4) The prepreg obtained in step (2) is impregnated in the second adhesive solution and dried to obtain the adhesive sheet;

[0013] (5) At least two of the adhesive sheets are stacked together as the core material, a fabric semi-cured sheet is laid on both sides of the core material, and copper foil is covered on the side of the fabric semi-cured sheet away from the core material. The sheets are then hot-pressed to obtain the CEM-1 copper foil laminate.

[0014] The preparation method provided by this invention involves first impregnating wood pulp fiber paper in a first adhesive solution. This adhesive solution system is an aqueous system, which has good wettability on the wood pulp fiber paper. Moreover, the adhesive solution system contains a reactive aqueous phosphorus-containing epoxy resin and an aqueous curing agent. These two can cure and react, improving the flame retardant efficiency, thereby reducing the amount of flame retardant used and avoiding the problem of adding a large amount of flame retardant in traditional methods. The resulting CEM-1 copper-clad laminate has good flame retardancy, as well as good heat resistance and punching processability.

[0015] Preferably, the epoxy equivalent of the reactive waterborne phosphorus-containing epoxy resin in step (1) is 350~650 g / eq, for example, it can be 350 g / eq, 380 g / eq, 400 g / eq, 420 g / eq, 430 g / eq, 450 g / eq, 460 g / eq, 480 g / eq, 500 g / eq, 520 g / eq, 530 g / eq, 550 g / eq, 560 g / eq, 580 g / eq, 600 g / eq, 620 g / eq, 630 g / eq or 650 g / eq, and specific values ​​between the above values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0016] Preferably, the phosphorus content of the reactive waterborne phosphorus-containing epoxy resin in step (1) is 1% to 2.5%, for example, it can be 1%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.6%, 1.7%, 1.8%, 1.9%, 2%, 2.1%, 2.2%, 2.3%, 2.4%, or 2.5%, and specific values ​​between the above values ​​are not exhaustively listed here for space limitations and for the sake of brevity. If the phosphorus content of the reactive waterborne phosphorus-containing epoxy resin is too low, it will lead to a decrease in the flame retardant performance of the CEM-1 copper-clad laminate.

[0017] Preferably, the reactive waterborne phosphorus-containing epoxy resin in step (1) includes any one or a combination of at least two of the following: reactive waterborne DOPO modified epoxy resin, reactive waterborne DOPO-HQ modified epoxy resin, and reactive waterborne DOPO-NQ modified epoxy resin.

[0018] Preferably, the water-based curing agent in step (1) is an amine curing agent, including any one or a combination of at least two of diamines, fatty amines, and polyamides.

[0019] Preferably, in step (1), based on 100 parts of the reactive waterborne phosphorus-containing epoxy resin, the amount of the waterborne curing agent is 10-30 parts, for example, 10 parts, 12 parts, 14 parts, 15 parts, 16 parts, 18 parts, 20 parts, 22 parts, 24 parts, 25 parts, 26 parts, 28 parts, or 30 parts, as well as specific values ​​between the above values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range. It should be noted that the amount of each component in the present invention is "parts by weight".

[0020] Preferably, in step (1), the solid content of the first adhesive liquid is 10% to 30%, for example, it can be 10%, 12%, 14%, 15%, 16%, 18%, 20%, 22%, 24%, 25%, 26%, 28% or 30%, and specific values ​​between the above values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0021] Preferably, the solvent in the first adhesive solution in step (1) is water. It should be noted that the first adhesive solution can be obtained by mixing a reactive waterborne phosphorus-containing epoxy resin with a solid content of 100%, a waterborne curing agent, and water, or it can be obtained by mixing a reactive waterborne phosphorus-containing epoxy resin with a solid content of less than 100% and a waterborne curing agent.

[0022] Preferably, the immersion time in step (2) is 5 to 15 seconds, for example, 5 seconds, 8 seconds, 10 seconds, 12 seconds, 13 seconds or 15 seconds, and specific values ​​between the above values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0023] Preferably, the drying temperature in step (2) is 210~230℃, for example, it can be 210℃, 215℃, 220℃, 225℃ or 230℃, and specific values ​​between the above points. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range. The drying time is 3~5min, for example, it can be 3min, 3.5min, 4min, 4.5min or 5min, and specific values ​​between the above points. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0024] Preferably, the epoxy resin in step (3) is a phosphorus-containing epoxy resin, including any one or a combination of at least two of DOPO-modified epoxy resin, DOPO-HQ-modified epoxy resin, and DOPO-NQ-modified epoxy resin. The epoxy resin in step (3) of this invention is an oil-based epoxy resin (also known as a solvent-based epoxy resin). Solvent-based epoxy resin adhesives use organic solvents (such as xylene, acetone, etc.) as diluents and dispersion media, which is its core characteristic distinguishing it from aqueous systems (which use water as a diluent).

[0025] Preferably, the curing agent in step (3) includes any one or a combination of at least two of phenolic curing agents, linear phenolic resin, and soybean oil toughened phenolic resin.

[0026] Preferably, the flame retardant filler in step (3) includes any one or a combination of at least two of aluminum hydroxide, ammonium polyphosphate, aluminum hypophosphite, and magnesium hydroxide.

[0027] Preferably, in step (3), based on 100 parts of epoxy resin, the amount of curing agent is 20-50 parts, for example, 20 parts, 22 parts, 24 parts, 25 parts, 26 parts, 28 parts, 30 parts, 32 parts, 34 parts, 35 parts, 36 parts, 38 parts, 40 parts, 42 parts, 44 parts, 45 parts, 46 parts, 48 ​​parts or 50 parts, and specific values ​​between the above points. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range. The amount of flame retardant filler is 10-20 parts, for example, 10 parts, 12 parts, 14 parts, 15 parts, 16 parts, 18 parts or 20 parts, and specific values ​​between the above points. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0028] Preferably, the organic solvent in step (3) includes one or a mixture of more than one of the following: ethers such as ethylene glycol methyl ether, diethylene glycol ethyl ether, and diethylene glycol butyl ether; ketones such as acetone, butanone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; aromatic hydrocarbons such as toluene, xylene, and mesitylene; or ester solvents such as ethoxyethyl acetate and ethyl acetate.

[0029] Preferably, in step (3), the second adhesive solution further includes a curing accelerator.

[0030] Preferably, the curing accelerator comprises any one or a combination of at least two of the following: tertiary amines, tertiary phosphines, organometallic complexes, quaternary ammonium salts, or imidazole compounds.

[0031] Preferably, based on 100 parts of epoxy resin, the amount of curing accelerator is 0.01 to 0.1 parts, for example, 0.01 parts, 0.02 parts, 0.03 parts, 0.05 parts, 0.06 parts, 0.08 parts, or 0.1 parts, as well as specific values ​​between the above values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0032] Preferably, in step (3), the solid content of the second adhesive is 50% to 70%, for example, it can be 50%, 52%, 54%, 55%, 56%, 58%, 60%, 62%, 64%, 65%, 66%, 68% or 70%, and specific values ​​between the above values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0033] Preferably, the immersion time in step (4) is 5 to 15 seconds, for example, 5 seconds, 8 seconds, 10 seconds, 12 seconds, 13 seconds or 15 seconds, and specific values ​​between the above values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0034] Preferably, the drying temperature in step (4) is 170~190℃, for example, it can be 170℃, 175℃, 180℃, 185℃ or 190℃, and specific values ​​between the above points. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range. The drying time is 2~4min, for example, it can be 2min, 2.5min, 3min, 3.5min or 4min, and specific values ​​between the above points. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0035] Preferably, the at least two images mentioned in step (5) are 2 to 8 images, for example, 2, 3, 4, 5, 6, 7 or 8 images, as well as specific image values ​​between the above image values. Due to space limitations and for the sake of brevity, this invention will not exhaustively list the specific image values ​​included in the range.

[0036] Preferably, the prepreg in step (5) comprises a glass fiber cloth-based prepreg. The present invention does not limit the preparation method of the glass fiber cloth-based prepreg; it can be prepared according to existing methods or purchased commercially.

[0037] Preferably, the hot pressing temperature in step (5) is 150~170℃, for example, it can be 150℃, 155℃, 160℃, 165℃ or 170℃, and specific values ​​between the above points. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range. The hot pressing pressure is 4~6MPa, for example, it can be 4MPa, 4.5MPa, 5MPa, 5.5MPa or 6MPa, and specific values ​​between the above points. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range. The hot pressing time is 110~130min, for example, it can be 110min, 115min, 120min, 125min or 130min, and specific values ​​between the above points. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0038] The "parts" and "parts by weight" used in this invention are calculated based on solid content and do not include solvents, dispersants, etc.

[0039] As a preferred embodiment of the present invention, the preparation method includes the following steps:

[0040] (1) Mix 100 parts of reactive waterborne phosphorus-containing epoxy resin, 10-30 parts of waterborne curing agent and water to obtain a first adhesive solution with a solid content of 10%-30%;

[0041] (2) Impregnate the wood pulp fiber paper in the first adhesive solution for 5-15 seconds, and then dry it at 210-230℃ for 3-5 minutes to obtain the prepreg;

[0042] (3) Mix 100 parts of epoxy resin, 20-50 parts of curing agent, 10-20 parts of flame retardant filler, optional 0.01-0.1 parts of curing accelerator and organic solvent to obtain a second adhesive with a solid content of 50%-70%;

[0043] (4) Immerse the prepreg obtained in step (2) in the second adhesive solution for 5~15s, and then dry it at 170~190℃ for 2~4min to obtain the adhesive sheet;

[0044] (5) Stack 2 to 8 of the adhesive sheets together as the core material, cover both sides of the core material with a fabric semi-cured sheet, and then cover the side of the fabric semi-cured sheet away from the core material with copper foil. Hot press at 150 to 170°C and 4 to 6 MPa for 110 to 130 minutes to obtain the CEM-1 copper foil laminate.

[0045] In a second aspect, the present invention provides a CEM-1 copper clad laminate, wherein the CEM-1 copper clad laminate is prepared by the preparation method described in the first aspect.

[0046] Compared with the prior art, the present invention has the following beneficial effects:

[0047] The preparation method provided by this invention involves first impregnating wood pulp fiber paper in a first adhesive solution. This adhesive solution system is an aqueous system, which has good wettability on the wood pulp fiber paper. Moreover, the adhesive solution system contains a reactive aqueous phosphorus-containing epoxy resin and an aqueous curing agent. These two can cure and react, improving the flame retardant efficiency, thereby reducing the amount of flame retardant used and avoiding the problem of adding a large amount of flame retardant in traditional methods. The resulting CEM-1 copper-clad laminate has good flame retardancy, as well as good heat resistance and punching processability.

[0048] The CEM-1 copper-clad laminate prepared by the method provided in this invention has a thermal stress (288℃ immersion soldering) ≥80s, punching processability meets the requirements of level 5, and flame retardancy meets the V-0 level. Detailed Implementation

[0049] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention in any way.

[0050] Unless otherwise specified, the raw materials used in the following examples and comparative examples are as follows:

[0051] (1) Reactive waterborne phosphorus-containing epoxy resins with epoxy equivalents of 250 g / eq, 350 g / eq, 500 g / eq, 650 g / eq, and 850 g / eq, and phosphorus content of 0.5% or 1.5%, and the following grades:

[0052]

[0053] (2) Water-based curing agent, water-based polyamide, brand name: YR-204, Zhangjiagang Yarui Chemical Technology Co., Ltd.;

[0054] (3) Epoxy resin, brand name: TU-3890, Tongyu Chemical Co., Ltd.;

[0055] (4) Curing agent, brand: PF-5850, Shandong Shengquan Chemical Co., Ltd.;

[0056] (5) Flame retardant filler, aluminum hypophosphite, grade: PY-PAL433, Guangdong Yulong Technology Co., Ltd.;

[0057] (6) Curing accelerator, 2-methylimidazole.

[0058] Example 1

[0059] This embodiment provides a method for preparing a CEM-1 copper-clad laminate, the method comprising the following steps:

[0060] (1) Mix 100 parts of reactive waterborne phosphorus-containing epoxy resin, 10 parts of waterborne curing agent and water, stir evenly to obtain a first adhesive solution with a solid content of 20%.

[0061] (2) The wood pulp fiber paper is impregnated in the first adhesive solution for 10 seconds and then dried at 220°C for 4 minutes to obtain the prepreg;

[0062] (3) Mix 100 parts epoxy resin, 20 parts curing agent, 10 parts flame retardant filler, 0.02 parts curing accelerator and organic solvent (acetone), stir evenly to obtain a second adhesive with a solid content of 50%;

[0063] (4) The prepreg obtained in step (2) is immersed in the second adhesive solution for 12 seconds, and then dried at 180°C for 3 minutes to obtain the adhesive sheet;

[0064] (5) Five adhesive sheets are stacked together as the core material. A fabric semi-cured sheet (specifically a glass fiber cloth-based semi-cured sheet) is laid on both sides of the core material. Copper foil is then covered on the side of each fabric semi-cured sheet away from the core material. The sheet is hot-pressed at 150°C and 4MPa for 110 minutes to obtain the CEM-1 copper foil laminate with a thickness of 1.6 mm.

[0065] In this embodiment, the specific types of raw materials are shown in Table 1. The glass fiber cloth-based prepreg is prepared by the following method: first, the dicyandiamide curing agent is dissolved in DMF, then mixed with epoxy resin (TU-3890) to prepare a 72% solid content adhesive solution, then glass fiber cloth is impregnated with the adhesive solution, and dried in an oven to obtain the fabric prepreg.

[0066] Examples 2-8

[0067] A method for preparing a CEM-1 copper-clad laminate differs from Example 1 in that the formulations of the first adhesive, the second adhesive, and the preparation conditions are different, as shown in Tables 1 and 2. All component amounts are expressed in parts by weight. Items not shown in Tables 1 and 2 are considered identical to those in Example 1.

[0068] Table 1

[0069]

[0070] Table 2

[0071]

[0072] Comparative Example 1

[0073] The only difference between this comparative example and Example 1 is that the reactive waterborne phosphorus-containing epoxy resin in the first adhesive solution is replaced with an equal weight proportion of ordinary phosphorus-containing epoxy resin (brand name TU-3890).

[0074] Comparative Example 2

[0075] The only difference between this comparative example and Example 1 is that the water-based curing agent in the first adhesive solution is replaced with an equal amount of dicyandiamide by weight.

[0076] Comparative Example 3

[0077] This comparative example provides a method for preparing a CEM-1 copper-clad laminate, the method comprising the following steps:

[0078] (1) Mix 100 parts of reactive waterborne phosphorus-containing epoxy resin, 10 parts of waterborne curing agent and water, stir evenly to obtain a first adhesive solution with a solid content of 20%.

[0079] (2) Mix 100 parts epoxy resin, 20 parts curing agent, 10 parts flame retardant filler, 0.02 parts curing accelerator and organic solvent (acetone), stir evenly to obtain a second adhesive with a solid content of 50%;

[0080] (3) The wood pulp fiber paper is first immersed in the second adhesive solution for 12 seconds, then dried at 180°C for 3 minutes, then immersed in the first adhesive solution for 10 seconds, and then dried at 220°C for 4 minutes to obtain the adhesive sheet.

[0081] (4) Five adhesive sheets are stacked together as the core material. A fabric semi-cured sheet (specifically a glass fiber cloth-based semi-cured sheet) is laid on both sides of the core material. Copper foil is then covered on the side of each fabric semi-cured sheet away from the core material. The sheet is hot-pressed at 150°C and 4MPa for 110 minutes to obtain the CEM-1 copper foil laminate with a thickness of 1.6 mm.

[0082] The preparation method of the glass fiber cloth-based prepreg is the same as in Example 1.

[0083] The performance of the CEM-1 copper-clad laminate provided in the embodiments and comparative examples of the present invention was tested, and the specific methods are as follows:

[0084] (1) Thermal stress (288℃ immersion welding): The thermal stress test method specified in GT / T 4722-2017 shall be used for determination;

[0085] (2) Punching processability: The punching processability test method specified in GB / T 4722-2017 shall be used; the test shall be conducted in accordance with UL-94 standard.

[0086] (3) Flame retardancy: Tested according to UL94 “50W (20mm) vertical burning test: V-0, V-1 and V-2” test method.

[0087] The performance test results are shown in Table 3.

[0088] Table 3

[0089]

[0090] As can be seen from Table 3, the CEM-1 copper-clad laminate prepared by the preparation methods provided in Examples 1-3 and 7-8 of this invention not only has good flame retardancy (meets V-0 level), but also has good heat resistance (thermal stress (288℃ immersion soldering) ≥80s) and processability (punching processability meets level 5 requirements).

[0091] Compared with Example 1, the heat resistance of the CEM-1 copper-clad laminate prepared by the preparation methods provided in Examples 4 and 5 decreased, and the flame retardancy of the CEM-1 copper-clad laminate prepared by the preparation method provided in Example 6 decreased.

[0092] Compared with Example 1, Comparative Example 1 uses ordinary phosphorus-containing epoxy resin, which is insoluble in water and cannot be used to make boards. The thermal stress, punching processability and flame retardancy of the CEM-1 copper-clad laminate provided by Comparative Example 2 are significantly reduced. The thermal stress of the CEM-1 copper-clad laminate provided by Comparative Example 3 is drastically reduced, and the flame retardancy is rated as V-1.

[0093] The applicant declares that the present invention illustrates the CEM-1 copper-clad laminate and its preparation method through the above embodiments, but the present invention is not limited to the above embodiments, that is, it does not mean that the present invention must rely on the above embodiments to be implemented. Those skilled in the art should understand that any improvements to the present invention, equivalent substitutions of the raw materials used in the present invention, additions of auxiliary components, and selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A method for preparing a CEM-1 copper-clad laminate, characterized in that, The preparation method includes the following steps: (1) Mix reactive waterborne phosphorus-containing epoxy resin and waterborne curing agent to obtain the first adhesive solution; (2) Impregnate the wood pulp fiber paper in the first adhesive solution and dry it to obtain the prepreg; (3) Mix epoxy resin, curing agent, flame retardant filler and organic solvent to obtain the second adhesive solution; (4) The prepreg obtained in step (2) is impregnated in the second adhesive solution and dried to obtain the adhesive sheet; (5) At least two of the adhesive sheets are stacked together as the core material, a fabric semi-cured sheet is laid on both sides of the core material, and copper foil is covered on the side of the fabric semi-cured sheet away from the core material. The sheets are then hot-pressed to obtain the CEM-1 copper foil laminate.

2. The preparation method according to claim 1, characterized in that, The epoxy equivalent of the reactive waterborne phosphorus-containing epoxy resin in step (1) is 350~650 g / eq; Preferably, the phosphorus content of the reactive waterborne phosphorus-containing epoxy resin in step (1) is 1% to 2.5%; Preferably, the reactive waterborne phosphorus-containing epoxy resin in step (1) includes any one or a combination of at least two of the following: reactive waterborne DOPO modified epoxy resin, reactive waterborne DOPO-HQ modified epoxy resin, and reactive waterborne DOPO-NQ modified epoxy resin. Preferably, the water-based curing agent in step (1) is an amine curing agent, including any one or a combination of at least two of diamines, fatty amines, and polyamides.

3. The preparation method according to claim 1 or 2, characterized in that, In step (1), based on 100 parts of the reactive waterborne phosphorus-containing epoxy resin, the amount of the waterborne curing agent is 10 to 30 parts. Preferably, in step (1), the solid content of the first adhesive solution is 10%~30%; Preferably, the solvent in the first adhesive solution in step (1) is water.

4. The preparation method according to any one of claims 1-3, characterized in that, The soaking time in step (2) is 5~15s; Preferably, the drying temperature in step (2) is 210~230℃ and the drying time is 3~5min.

5. The preparation method according to any one of claims 1-4, characterized in that, The epoxy resin mentioned in step (3) is a phosphorus-containing epoxy resin, including any one or a combination of at least two of DOPO modified epoxy resin, DOPO-HQ modified epoxy resin, and DOPO-NQ modified epoxy resin. Preferably, the curing agent in step (3) includes any one or a combination of at least two of phenolic curing agents, linear phenolic resin, and soybean oil toughened phenolic resin; Preferably, the flame retardant filler in step (3) includes any one or a combination of at least two of aluminum hydroxide, ammonium polyphosphate, aluminum hypophosphite, and magnesium hydroxide; Preferably, in step (3), based on 100 parts of epoxy resin, the amount of curing agent is 20-50 parts and the amount of flame retardant filler is 10-20 parts.

6. The preparation method according to any one of claims 1-5, characterized in that, Step (3) The second adhesive also includes a curing accelerator; Preferably, the curing accelerator comprises any one or a combination of at least two of the following: tertiary amines, tertiary phosphines, organometallic complexes, quaternary ammonium salts, or imidazole compounds; Preferably, based on 100 parts of epoxy resin, the amount of curing accelerator is 0.01 to 0.1 parts; Preferably, in step (3), the solid content of the second adhesive is 50% to 70%.

7. The preparation method according to any one of claims 1-6, characterized in that, The soaking time in step (4) is 5~15s; Preferably, the drying temperature in step (4) is 170~190℃ and the drying time is 2~4min.

8. The preparation method according to any one of claims 1-7, characterized in that, The "at least two" mentioned in step (5) refers to 2 to 8 images; Preferably, the prepreg in step (5) comprises a glass fiber cloth-based prepreg; Preferably, the hot pressing temperature in step (5) is 150~170℃, the hot pressing pressure is 4~6MPa, and the hot pressing time is 110~130min.

9. A preparation method according to any one of claims 1-8, characterized in that, The preparation method includes the following steps: (1) Mix 100 parts of reactive waterborne phosphorus-containing epoxy resin, 10-30 parts of waterborne curing agent and water to obtain a first adhesive solution with a solid content of 10%-30%; (2) Impregnate the wood pulp fiber paper in the first adhesive solution for 5-15 seconds, and then dry it at 210-230℃ for 3-5 minutes to obtain the prepreg; (3) Mix 100 parts of epoxy resin, 20-50 parts of curing agent, 10-20 parts of flame retardant filler, 0.01-0.1 parts of curing accelerator and organic solvent to obtain a second adhesive with a solid content of 50%-70%; (4) The prepreg obtained in step (2) is immersed in the second adhesive solution for 5~15s, and then dried at 170~190℃ for 2~4min to obtain the adhesive sheet; (5) Stack 2 to 8 of the adhesive sheets together as the core material, cover both sides of the core material with a fabric semi-cured sheet, and then cover the side of the fabric semi-cured sheet away from the core material with copper foil. Hot press at 150 to 170°C and 4 to 6 MPa for 110 to 130 minutes to obtain the CEM-1 copper foil laminate.

10. A CEM-1 copper-clad laminate, characterized in that, The CEM-1 copper-clad laminate is prepared using the preparation method described in any one of claims 1-9.

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