Resin composition, adhesive sheet containing resin composition, copper-clad plate containing resin composition and preparation method of resin composition

Abstract

The invention discloses a resin composition, a bonding sheet containing the resin composition, a copper-clad plate containing the resin composition and a preparation method of the resin composition. The resin composition comprises the following raw materials in parts by weight: 65-75 parts of ceramic powder, 25-35 parts of a modified polytetrafluoroethylene emulsion, 0.3-5 parts of a nonionic water-based anti-settling agent, 15-55 parts of an organic solvent and 10-25 parts of solvent oil. The preparation method specifically comprises the following steps: (1) vacuum mixing: adding a modified polytetrafluoroethylene emulsion into a non-ionic water-based anti-settling agent, uniformly mixing, then adding ceramic powder, and performing vacuum mixing to achieve a uniform suspension state; and (2) demulsification resinification: adding the solvent oil, uniformly mixing, then adding the organic solvent while stirring, and stirring, mixing and demulsifying to obtain the product. According to the preparation method disclosed by the invention, a preparation process is deeply studied, the ceramic is used for filling the modified polytetrafluoroethylene emulsion and the non-ionic anti-settling agent to uniformly suspend in a distribution state, and resin fibration is formed through demulsification of the organic solvent within a short time to retain the flexibility, so that the aim of preparing a base material and an FCCL with the ultrathin thickness of less than 0.050 mm is fulfilled.

Description

Technical Field

[0001] The present invention relates to the technical field of resin compositions, and more specifically, to a resin composition, an adhesive sheet containing the same, a copper clad laminate, and a preparation method thereof. Background Art

[0002] For high-frequency, high-speed, and packaging materials, with the development towards high functionality and high-density miniaturization, faster transmission speeds and lower transmission losses are required. Among them, substrates without glass fiber, thinner base materials, high-dielectric and ultra-low-loss materials, and extremely thin low-RZ copper foils are all effective ways to reduce transmission losses.

[0003] Polytetrafluoroethylene resin has relatively lower transmission losses compared to mainstream hydrocarbon resins for high-frequency use, polyimide resins, mainstream polyphenylene ethers for high-speed use, LCP liquid crystal polymer resins, etc., and is one of the preferred solutions for preparing high-performance thin substrates and flexible copper clad laminates (FCCL).

[0004] The main preparation methods for thinner base materials mainly include using polytetrafluoroethylene emulsion coating and casting molding. The disadvantages of the preparation are that high-temperature sintering above 330°C is required, the production process cost is high, and the thermal expansion coefficient of the base material is relatively large, making it difficult to meet the higher application requirements of high-frequency. In addition, Patent CN113306227B uses polytetrafluoroethylene resin powder for extrusion and calendering molding. Due to the large toughness of the resin powder, after the resin is fibrillated, it lacks flexibility when preparing a coreless base material with a thickness of 0.150 mm or less, and it is difficult to prepare an FCCL base material with a thickness of 0.050 mm or less that has uniform thickness and stable performance.

[0005] Currently, there are also methods of using ceramic fillers to fill polytetrafluoroethylene emulsion, followed by high-speed shear stirring, drying, and then coating or calendering to prepare thin base materials. The disadvantage of this method is that small bubbles are generated during high-speed mixing, resulting in uneven voids and poor electrical properties. In addition, there are also methods of using ceramic fillers to fill polytetrafluoroethylene emulsion, using a flocculant for stirring, drying, and then calendering to prepare thin base materials. The disadvantage of this method is that the flocculant needs to be removed at high temperature or through more steps and it is difficult to achieve a low expansion coefficient. There are also methods of using ceramic-filled PTFE resin turning films, and the disadvantage of this method is that it is difficult to achieve high-fill thin turning.

[0006] Therefore, how to develop a resin composition with excellent performance for preparing copper clad laminates is an urgent problem to be solved by those skilled in the art. Summary of the Invention

[0007] In view of this, the purpose of the present invention is to provide a resin composition, an adhesive sheet containing the same, a copper clad laminate, and a preparation method thereof to solve the deficiencies in the prior art.

[0008] To achieve the above purpose, the present invention adopts the following technical solutions:

[0009] A resin composition comprising raw materials in the following parts by weight: 65 - 75 parts of ceramic powder, 25 - 35 parts of modified polytetrafluoroethylene emulsion, 0.3 - 5 parts of non-ionic aqueous anti-settling agent, 15 - 55 parts of organic solvent, and 10 - 25 parts of solvent oil.

[0010] Furthermore, the above-mentioned ceramic powder is at least one of silicon nitride, boron nitride, alumina, silica, titanium dioxide, strontium titanate, barium strontium titanate, barium titanium silicate, rare earth, and negative thermal expansion coefficient materials.

[0011] Still further, the structure of the above-mentioned ceramic powder is angular, flaky, spherical, spherical aggregates, hollow spherical, fibrous or sponge-like ceramic powder, preferably sponge-like ceramic powder, more preferably nano-scale sponge-like mixture; wherein, the sphericity of the spherical shape ≥ 95%, and the particle size is 0.001 - 15 μm. It can be preferably selected according to the type of copper clad laminate to be prepared. For preparing low dielectric and low loss, hollow sphere silicon and sphere silicon combination are preferred; for high dielectric and low loss, titanium dioxide, barium titanium silicate, and strontium titanate combination are preferred; for high thermal conductivity copper clad laminate, boron nitride, alumina, and silica combination are preferred. When the filler ratio is higher than 65%, nano-scale sponge-like ceramic powder is used in combination, preferably alumina and titanium dioxide combination, to achieve a thermal expansion coefficient close to zero. Through the grading and mixing of angular, spherical, and sponge-like particles, the highest filler ratio reaches 75%, realizing thin-type and high filling.

[0012] Furthermore, the above-mentioned modified polytetrafluoroethylene emulsion is at least one of polytetrafluoroethylene (PTFE) emulsion, polytetrafluoroethylene (PTFE) suspension resin powder, polytetrafluoroethylene (PTFE) dispersion resin powder, fluorinated ethylene propylene copolymer (FEP), soluble polytetrafluoroethylene (PFA), and polyimide, and the solid content is 60%. Preferably, it is PFA and FEP resin emulsion modified polytetrafluoroethylene emulsion. The thin-type copper clad laminate prepared according to this formulation can reduce the highest lamination temperature and maintain high performance and low loss.

[0013] Furthermore, the above-mentioned non-ionic aqueous anti-settling agent is at least one of polyethylene glycol, polyethylene glycol laurate, polyurethane, and cellulose derivatives. Preferably, it is polyethylene glycol 600 with a boiling point below 300°C. This agent is solid below 10°C and liquid at normal temperature of 10 - 40°C, which is very suitable for mixing with modified polytetrafluoroethylene emulsion to achieve a uniform suspension state, enabling the demulsification resinification step to achieve a highly uniform fibrous network dispersion structure, and polyethylene glycol 600 can be completely removed below 300°C without residue, with obvious advantages.

[0014] Further, the above-mentioned organic solvent is at least one of isopropanone, methyl ethyl ketone, acetone, absolute ethanol, and γ-methacryloxypropyltrimethoxysilane. Preferably, it is a mixture of absolute ethanol and γ-methacryloxypropyltrimethoxysilane (KH570), preferably 30% by mass of the total resin mixture. It has high demulsification efficiency, is mild, rapid, and easy to remove. When combined with the foregoing process mixture in an amount of 50-100 kg, it results in high demulsification resinification and fibrosis, uniform distribution, and high flexibility.

[0015] Further, the above-mentioned solvent oil is at least one of odorless kerosene, white oil, isoparaffin, and aviation kerosene. Preferably, it is an isoparaffin with a median boiling point of 150-230 °C, more preferably an isoparaffin with a boiling point of 200 °C. The main purpose is to lubricate the extrusion and calendering process. By directly adding and mixing evenly, the selection of the median boiling point is to maintain a certain volatile VC when removing most of the organic solvents and water (polytetrafluoroethylene emulsion is a water / fluororesin mixture) at 150 °C in the foregoing short-time drying process, without affecting the implementation of the next extrusion and calendering of the solvent oil.

[0016] A method for preparing the above resin composition specifically includes the following steps:

[0017] (1) Vacuum mixing

[0018] Add the modified polytetrafluoroethylene emulsion to the non-ionic aqueous anti-settling agent, mix evenly, then add the ceramic powder, and perform vacuum mixing until a uniform suspension state is achieved to obtain a preliminary mixture.

[0019] (2) Demulsification resinification

[0020] Add the solvent oil to the preliminary mixture, mix evenly, and then add the organic solvent while stirring to perform stirring and mixing for demulsification, thereby obtaining the resin composition.

[0021] Further, in the above step (1), the time for vacuum mixing is 1-4 h;

[0022] The further beneficial effect of adopting the above is that the present invention uses vacuum feeding and vacuum mixing. This method can eliminate feeding dust and impurities and achieve a bubble-free state in vacuum mixing. Preferably, 50-100 kg of ingredients are mixed. Within this range, the feasibility of demulsification resinification is ensured, and it does not affect the batch production efficiency.

[0023] Further, in the above step (2), the time for stirring and mixing for demulsification is 1-3 min.

[0024] An adhesive sheet containing the above resin composition.

[0025] A method for preparing the above adhesive sheet specifically includes the following steps:

[0026] (1) Short-time drying

[0027] The resin composition is dried briefly to remove the organic solvent and most of the non-ionic aqueous anti-settling agent, obtaining a dried resin composition;

[0028] (2) Sheet extrusion

[0029] The dried resin composition is pre-pressed into a cylindrical shape and sheet-extruded to obtain a continuously rewound film;

[0030] (3) Roll die into sheets

[0031] The continuously rewound film is continuously roll-die into sheets to obtain a continuously rewound adhesive sheet;

[0032] (4) Low-temperature baking

[0033] The continuously rewound adhesive sheet is baked at a low temperature to further remove the organic solvent, non-ionic aqueous anti-settling agent and solvent oil, thus obtaining the adhesive sheet.

[0034] Furthermore, in the above step (1), the temperature for brief drying is 90 - 150 °C and the time is 30 min.

[0035] Furthermore, in the above step (2), the width of the continuously rewound film is 10 - 30 cm and the thickness is 1 - 5 mm.

[0036] The beneficial effect of the above further steps is that the extrusion process is similar to the extrusion process of PTFE tape, and can be continuously extruded in batches with multiple feedings, so it does not affect the overall mass production and efficiency. Moreover, it is easier to control the degree of uniformity for small-batch batching compared to tonnage batching.

[0037] Furthermore, in the above step (3), the temperature of the opposing rollers for continuous roll die into sheets is 50 - 150 °C; the width of the continuously rewound adhesive sheet is 45 - 55 cm and the thickness is 0.038 - 0.200 mm.

[0038] Furthermore, in the above step (4), the baking temperature is 160 - 300 °C and the time is 3 - 10 min; the thickness of the adhesive sheet is 0.070 - 0.200 mm.

[0039] A copper clad laminate contains the above adhesive sheet.

[0040] A method for preparing the above copper clad laminate specifically includes the following steps:

[0041] The adhesive sheet is cut, laminated and double-sided copper-clad or laminated with resin sheets on both sides and then copper-clad, and vacuum high-temperature oil pressure molding is carried out to obtain the copper clad laminate.

[0042] Further, the above resin sheet is at least one of a polytetrafluoroethylene resin film, a perfluoroethylene-propylene resin film, a tetrafluoroethylene-perfluoroalkoxy vinyl ether copolymer resin film, a double-sided modified polytetrafluoroethylene film, a polyimide resin film, a polydiene resin-coated film, and a polyphenylene ether resin-coated film.

[0043] Further, the maximum material temperature for the above vacuum high-temperature oil pressure molding is 200 - 395 °C, the pressure is 500 - 1000 N / cm 2 , and the pressure holding time is 1 - 3 h.

[0044] Another product of the above resin composition: The above adhesive sheet is double-sided activated: After treatment with dopamine impregnation, high-temperature plasma treatment, corona treatment, sodium treatment, nano-coating, grafted groups, etc., a hydrocarbon resin mixture (high-frequency hydrocarbon CT3330(L) copper-clad laminate resin glue sold by Chenzhou Gongtian Electronic Ceramics Technology Co., Ltd.) and a polyphenylene ether resin mixture (high-speed GTM70(L) copper-clad laminate resin glue sold by Chenzhou Gongtian Electronic Ceramics Technology Co., Ltd.) are double-sided coated and then dried. Double-sided copper plating can be vacuum laminated at room temperature of 200 - 300 °C to prepare a low-loss coreless copper-clad laminate for high-frequency and high-speed applications. Then, by using the double-sided copper-clad laminate prepared above as the core board, and cross-combining the core board + coated substrate + core board and laminating again, the purpose of manufacturing a multi-layer coreless copper-clad laminate is achieved.

[0045] It can be seen from the above technical solutions that, compared with the prior art, the beneficial effects of the present invention are as follows:

[0046] 1. The demulsification method is fast and effective, greatly reducing the working hours and making it easier to achieve batch production.

[0047] 2. The use of fibrous fillers in combination greatly improves the electrical properties of the product, and the coefficient of thermal expansion in the Z direction tends to zero.

[0048] 3. Through the preparation process and the synergistic effect of each component, the problems existing in the current thin-film polytetrafluoroethylene substrate (with a thickness of 0.050 mm and below), such as difficult thin-film formation, low filling amount, large coefficient of thermal expansion, and high dielectric loss, are solved.

[0049] 4. The prepared glass fiber-free substrate can replace the glass cloth, has good performance, and can be used for high-frequency, high-speed low-loss ultra-thin copper-clad laminates, FCCL substrates, and multi-layer copper-clad laminate coreless substrates, with obvious advantages.

[0050] 5. Through in-depth research on the preparation process, the present invention uses a ceramic-filled modified polytetrafluoroethylene emulsion and a non-ionic anti-settling agent to make the distribution state uniformly suspended. After demulsification with an organic solvent in a short time, resin fibrosis is formed while retaining its softness. After short-time drying, it is then sheet-extruded, rolled into sheets, and baked at a low temperature, thus achieving the purpose of preparing a substrate and FCCL with an ultra-thin thickness of less than 0.050 mm.

[0051] 6. The copper clad laminate of the present invention has the advantages of an ultra-thin thickness (0.010 - 0.050 mm), an adjustable dielectric constant (1.85 - 17.50), a low dielectric loss (0.00030 - 0.00180), a near-zero coefficient of thermal expansion and low loss characteristics at 50 - 260 °C, etc. It solves the problems existing in the prior art such as the difficulty in thinning ceramic-filled polytetrafluoroethylene products for high-frequency and high-speed applications, low filling amount, relatively large coefficient of thermal expansion, and relatively high dielectric loss. It is widely applicable to high-frequency, high-speed, high-performance ultra-thin copper clad laminates and FCCL substrates, and coreless substrates for multi-layer copper clad laminates. Specific Embodiments

[0052] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0053] Example 1

[0054] A resin composition, comprising raw materials in the following weights: 65 kg of ceramic powder (15 kg of fibrous alumina (Suzhou JinYi SC10), 50 kg of spherical silica (Suzhou JinYi Q200)), 35 kg of a modified polytetrafluoroethylene emulsion with a solid content of 60% (Zhonghao Chenguang SFN-1, PFA Daikin AW-1000G), 4 kg of a non-ionic aqueous anti-settling agent (Jiangxi Yisheng PEG-600), 30 kg of an organic solvent (Sinopharm anhydrous ethanol with a purity of ≥99.7%, Sinopharm KH570), and 15 kg of solvent oil (Japan's Idemitsu IP2028).

[0055] The preparation method of the above resin composition specifically includes the following steps:

[0056] (1) Vacuum mixing

[0057] Add the modified polytetrafluoroethylene emulsion to the non-ionic aqueous anti-settling agent, mix evenly, and then add the ceramic powder through an automatic vacuum feeding machine. Mix in a vacuum mixer for 4 h to reach a uniformly suspended state to obtain a preliminary mixture.

[0058] (2) Demulsification and resinification

[0059] Add solvent oil to the premix, mix evenly, and then add organic solvent while stirring. After stirring and mixing for 2 minutes, demulsify to obtain the resin composition.

[0060] The preparation method of the adhesive sheet containing the above resin composition specifically includes the following steps:

[0061] (1) Short-time drying

[0062] Place the resin composition in a constant-temperature degreasing oven and dry it at 150 °C for 30 minutes to remove the organic solvent and most of the non-ionic aqueous anti-settling agent, and obtain the dried resin composition;

[0063] (2) Sheet extrusion

[0064] Pour the dried resin composition into a pre-pressing machine to pre-press it into a cylinder, and then place it in an extruder. Extrude a continuously wound film with a width of 20 cm and a thickness of 5 mm through a heating cavity and a sheet basic die orifice;

[0065] (3) Rolling into sheets

[0066] Continuously roll the continuously wound film into sheets through a two-roll mill, and the temperature of the opposing rolls is 100 °C to obtain a continuously wound adhesive sheet with a width of 46 cm and a thickness of 0.070 mm;

[0067] (4) Low-temperature baking

[0068] Place the continuously wound adhesive sheet in a normal-temperature waste-removing constant-temperature oven and bake it at 300 °C for 10 minutes to further remove the organic solvent, non-ionic aqueous anti-settling agent, and solvent oil, and obtain the adhesive sheet.

[0069] The preparation method of the copper clad laminate containing the above adhesive sheet specifically includes the following steps:

[0070] Cut the adhesive sheet, perform lamination and double-sided copper cladding (18unHTE Luxembourg BF-NN-HT), and then perform hot pressing and forming through a vacuum high-temperature oil press. Keep the vacuum state, and keep the pressure at the highest material temperature of 385 °C and a pressure of 850 N / cm 2 for 2 hours to obtain the copper clad laminate.

[0071] Example 2

[0072] Resin composition, comprising raw materials in the following weights: 75 kg of ceramic powder (18 kg of fibrous alumina (Suzhou JinYi SC10), 56 kg of spherical silica (Suzhou JinYi Q200), 1 kg of angular alumina (Suzhou JinYi Y2)), 25 kg of modified polytetrafluoroethylene emulsion with a solid content of 60% (Zhonghao Chenguang SFN-1, PFA Daikin AW-1000G), 4 kg of non-ionic aqueous anti-settling agent (Jiangxi Yisheng PEG-600), 25 kg of organic solvent (Sinopharm anhydrous ethanol with purity ≥99.7%, Sinopharm KH570), and 18 kg of solvent oil (Japan Idemitsu IP2028).

[0073] The preparation method of the above resin composition specifically comprises the following steps:

[0074] (1) Vacuum mixing

[0075] Add the modified polytetrafluoroethylene emulsion to the non-ionic aqueous anti-settling agent, mix evenly, and then add the ceramic powder through an automatic vacuum feeding machine. Mix in a vacuum mixer for 4 h to reach a uniform suspension state to obtain a preliminary mixture.

[0076] (2) Demulsification and resinification

[0077] Add the solvent oil to the preliminary mixture, mix evenly, and then add the organic solvent while stirring. Demulsify after stirring and mixing for 2 min to obtain the resin composition.

[0078] The preparation method of an adhesive sheet containing the above resin composition specifically comprises the following steps:

[0079] (1) Short-time drying

[0080] Place the resin composition in a constant-temperature degreasing oven and dry it at 150°C for 30 min to remove the organic solvent and most of the non-ionic aqueous anti-settling agent to obtain the dried resin composition.

[0081] (2) Sheet extrusion

[0082] Pour the dried resin composition into a pre-pressing machine to pre-press it into a cylindrical shape, and then place it in an extruder. Extrude through a heating cavity and a sheet base die orifice to obtain a continuously wound film with a width of 20 cm and a thickness of 5 mm.

[0083] (3) Rolling into sheets

[0084] Continuously roll and form the continuously wound film through a two-roll calender. The temperature of the rolls is 100°C to obtain a continuously wound adhesive sheet with a width of 46 cm and a thickness of 0.070 mm.

[0085] (4) Low-temperature baking

[0086] Place the continuously rewound adhesive sheet in a room temperature waste removal constant temperature oven and bake it at a low temperature of 300 °C for 10 min to further remove organic solvents, non-ionic aqueous anti-settling agents, and solvent oil, thus obtaining the adhesive sheet.

[0087] A method for preparing a copper clad laminate containing the above adhesive sheet specifically includes the following steps:

[0088] Cut the adhesive sheet, perform lamination and double-sided copper cladding (18unHTE Luxembourg BF-NN-HT), and then carry out hot pressing and forming through a vacuum high-temperature oil press. Keep the vacuum state, and hold the pressure for 2 h under the conditions of a maximum material temperature of 385 °C and a pressure of 850 N / cm 2 to obtain the copper clad laminate.

[0089] Example 3

[0090] A resin composition includes raw materials with the following weights: 65 kg of ceramic powder (45 kg of fibrous titanium dioxide (Wuxi Longao T-G-25), 19 kg of fibrous alumina (Suzhou Jinyi SC10), 1 kg of angular alumina (Suzhou Jinyi Y2)), 35 kg of modified polytetrafluoroethylene emulsion with a solid content of 60% (Zhonghao Chenguang SFN-1, PFA Daikin AW-1000G), 4 kg of non-ionic aqueous anti-settling agent (Jiangxi Yisheng PEG-600), 30 kg of organic solvents (Sinopharm anhydrous ethanol with a purity of ≥99.7%, Sinopharm KH570), and 15 kg of solvent oil (Japan's Idemitsu IP2028).

[0091] The preparation method of the above resin composition specifically includes the following steps:

[0092] (1) Vacuum mixing

[0093] Add the modified polytetrafluoroethylene emulsion to the non-ionic aqueous anti-settling agent, mix evenly, and then add the ceramic powder through an automatic vacuum feeding machine. Mix in a vacuum mixer for 4 h to reach a uniform suspension state to obtain a preliminary mixture;

[0094] (2) Demulsification and resinification

[0095] Add the solvent oil to the preliminary mixture, mix evenly, and then add the organic solvent while stirring. Demulsify after stirring and mixing for 2 min to obtain the resin composition.

[0096] A method for preparing an adhesive sheet containing the above resin composition specifically includes the following steps:

[0097] (1) Short-time drying

[0098] Place the resin composition in a constant temperature degreasing oven and dry it at 150 °C for 30 min to remove organic solvents and most of the non-ionic aqueous anti-settling agent to obtain the dried resin composition;

[0099] (2) Sheet extrusion

[0100] Pour the dried resin composition into a pre-pressing machine to pre-press it into a cylindrical shape, then place it in an extruder and extrude a continuously wound film with a width of 20 cm and a thickness of 5 mm through a heating cavity and a sheet base die orifice;

[0101] (3) Rolling into sheets

[0102] Continuously roll and form the continuously wound film through a two-roll mill. The temperature of the opposing rolls is 100 °C to obtain a continuously wound adhesive sheet with a width of 46 cm and a thickness of 0.070 mm;

[0103] (4) Low-temperature baking

[0104] Place the continuously wound adhesive sheet in a normal-temperature waste-removing constant-temperature oven and bake it at 300 °C for 10 min to further remove the organic solvent, non-ionic aqueous anti-settling agent, and solvent oil, thus obtaining the adhesive sheet.

[0105] A method for preparing a copper-clad laminate containing the above-mentioned adhesive sheet specifically includes the following steps:

[0106] Cut the adhesive sheet, perform lamination and double-sided copper cladding (18unHTE Luxembourg BF-NN-HT), and then perform hot pressing through a vacuum high-temperature hydraulic press. Maintain the vacuum state and hold the pressure at the highest material temperature of 385 °C and a pressure of 850 N / cm 2 for 2 h to obtain the copper-clad laminate.

[0107] Example 4

[0108] The resin composition includes raw materials with the following weights: 65 kg of ceramic powder (57 kg of fibrous titanium dioxide (Wuxi Longao T-G-25), 6 kg of fibrous alumina (Suzhou Jinyi SC10), 2 kg of angular alumina (Suzhou Jinyi Y2)), 35 kg of modified polytetrafluoroethylene emulsion with a solid content of 60% (Zhonghao Chenguang SFN-1, PFA Daikin AW-1000G), 4 kg of non-ionic aqueous anti-settling agent (Jiangxi Yisheng PEG-600), 30 kg of organic solvent (Sinopharm anhydrous ethanol with a purity of ≥99.7%, Sinopharm KH570), and 15 kg of solvent oil (Japan's Idemitsu IP2028).

[0109] The preparation method of the above resin composition specifically includes the following steps:

[0110] (1) Vacuum mixing

[0111] Add the modified polytetrafluoroethylene emulsion to the non-ionic aqueous anti-settling agent, mix evenly, and then add the ceramic powder through an automatic vacuum feeding machine. Mix in a vacuum mixer for 4 h to reach a uniform suspension state to obtain a preliminary mixture;

[0112] (2) Demulsification and resinification

[0113] Add solvent oil to the initial mixture, mix evenly, then add organic solvent while stirring. After stirring and mixing for 2 minutes, demulsify to obtain the resin composition.

[0114] The preparation method of the adhesive sheet containing the above resin composition specifically includes the following steps:

[0115] (1) Short-time drying

[0116] Place the resin composition in a constant-temperature degreasing oven and dry it at 150 °C for 30 minutes to remove the organic solvent and most of the non-ionic aqueous anti-settling agent, obtaining the dried resin composition;

[0117] (2) Sheet extrusion

[0118] Pour the dried resin composition into a pre-pressing machine to pre-press it into a cylindrical shape, then place it in an extruder and extrude it through a heating cavity and a sheet-based die orifice to obtain a continuously wound film with a width of 20 cm and a thickness of 5 mm;

[0119] (3) Rolling into sheets

[0120] Continuously roll the continuously wound film into sheets through a two-roll mill. The temperature of the opposing rolls is 100 °C to obtain a continuously wound adhesive sheet with a width of 46 cm and a thickness of 0.070 mm;

[0121] (4) Low-temperature baking

[0122] Place the continuously wound adhesive sheet in a room-temperature waste-removing constant-temperature oven and bake it at 300 °C for 10 minutes to further remove the organic solvent, non-ionic aqueous anti-settling agent, and solvent oil, obtaining the adhesive sheet.

[0123] The preparation method of the copper-clad laminate containing the above adhesive sheet specifically includes the following steps:

[0124] Cut the adhesive sheet, perform lamination and double-sided copper cladding (18unHTE Luxembourg BF-NN-HT), and then perform hot pressing and forming through a vacuum high-temperature oil press. Keep the vacuum state, and hold the pressure at the highest material temperature of 385 °C and a pressure of 850 N / cm 2 for 2 hours to obtain the copper-clad laminate.

[0125] Example 5

[0126] Resin composition, comprising raw materials in the following weights: 65 kg of ceramic powder (fibrous titanium dioxide (Wuxi Longao T-G-25) 64 kg, angular alumina (Suzhou Jinyi Y2) 1 kg), 35 kg of modified polytetrafluoroethylene emulsion with a solid content of 60% (Zhonghao Chenguang SFN-1, PFA Daikin AW-1000G), 4 kg of non-ionic aqueous anti-settling agent (Jiangxi Yisheng PEG-600), 30 kg of organic solvent (Sinopharm anhydrous ethanol with a purity of ≥99.7%, Sinopharm KH570), and 15 kg of solvent oil (Idemitsu IP2028, Japan).

[0127] The preparation method of the above resin composition specifically comprises the following steps:

[0128] (1) Vacuum mixing

[0129] Add the modified polytetrafluoroethylene emulsion to the non-ionic aqueous anti-settling agent, mix evenly, then add the ceramic powder through an automatic vacuum feeding machine, and mix in a vacuum mixer for 4 h to reach a uniform suspension state to obtain a preliminary mixture;

[0130] (2) Demulsification and resinification

[0131] Add the solvent oil to the preliminary mixture, mix evenly, then add the organic solvent while stirring, and demulsify after stirring and mixing for 2 min to obtain the resin composition.

[0132] The preparation method of an adhesive sheet containing the above resin composition specifically comprises the following steps:

[0133] (1) Short-time drying

[0134] Place the resin composition in a constant-temperature degreasing oven and dry it at 150 °C for 30 min to remove the organic solvent and most of the non-ionic aqueous anti-settling agent to obtain the dried resin composition;

[0135] (2) Sheet extrusion

[0136] Pour the dried resin composition into a pre-pressing machine to pre-press it into a cylindrical shape, then place it in an extruder, and extrude a continuously wound film with a width of 20 cm and a thickness of 5 mm through a heating cavity and a sheet base die orifice;

[0137] (3) Rolling into sheets

[0138] Continuously roll the continuously wound film into sheets through a calender, and the temperature of the opposing rollers is 100 °C to obtain a continuously wound adhesive sheet with a width of 46 cm and a thickness of 0.070 mm;

[0139] (4) Low-temperature baking

[0140] Place the continuously rewound adhesive sheet in a normal-temperature waste-removing constant-temperature oven and bake it at a low temperature of 300 °C for 10 minutes to further remove organic solvents, non-ionic aqueous anti-settling agents, and solvent oil, thus obtaining the adhesive sheet.

[0141] A method for preparing a copper-clad laminate containing the above-mentioned adhesive sheet specifically includes the following steps:

[0142] Cut the adhesive sheet, perform lamination and double-sided copper cladding (18unHTE Luxembourg BF-NN-HT), and then carry out hot pressing and forming through a vacuum high-temperature oil press, maintaining a vacuum state, with a maximum material temperature of 385 °C and a pressure of 850 N / cm 2 Pressurize for 2 hours under these conditions to obtain the copper-clad laminate.

[0143] Example 6

[0144] A resin composition, including raw materials with the following weights: ceramic powder (fibrous titanium dioxide (Wuxi Longao T-G-25) 8 kg, spherical silica (Suzhou Jinyi Q200) 12 kg, spherical boron nitride (SM-SN) 45 kg) 65 kg, modified polytetrafluoroethylene emulsion with a solid content of 60% (Zhonghao Chenguang SFN-1, PFA Daikin AW-1000G) 35 kg, non-ionic aqueous anti-settling agent (Jiangxi Yisheng PEG-600) 4 kg, organic solvents (Sinopharm anhydrous ethanol purity ≥ 99.7%, Sinopharm KH570) 30 kg, and solvent oil (Japan's Idemitsu IP2028) 15 kg.

[0145] The preparation method of the above resin composition specifically includes the following steps:

[0146] (1) Vacuum mixing

[0147] Add the modified polytetrafluoroethylene emulsion to the non-ionic aqueous anti-settling agent, mix evenly, and then add the ceramic powder through an automatic vacuum feeding machine. Mix in a vacuum mixer for 4 hours to reach a uniform suspension state to obtain a preliminary mixture;

[0148] (2) Demulsification and resinification

[0149] Add the solvent oil to the preliminary mixture, mix evenly, and then add the organic solvent while stirring. Demulsify after stirring and mixing for 2 minutes to obtain the resin composition.

[0150] The preparation method of an adhesive sheet containing the above resin composition specifically includes the following steps:

[0151] (1) Short-time drying

[0152] Place the resin composition in a constant-temperature degreasing oven and dry it at 150 °C for 30 minutes to remove organic solvents and most of the non-ionic aqueous anti-settling agent, obtaining the dried resin composition;

[0153] (2) Sheet extrusion

[0154] Pour the dried resin composition into a pre - press to pre - press it into a cylindrical shape, and then place it in an extruder. Extrude a continuously wound film with a width of 20 cm and a thickness of 5 mm through a heating cavity and a sheet - based die orifice.

[0155] (3) Rolling into sheets

[0156] Continuously roll the continuously wound film into sheets through a two - roll mill. The temperature of the opposing rolls is 100 °C to obtain a continuously wound adhesive sheet with a width of 46 cm and a thickness of 0.070 mm.

[0157] (4) Low - temperature baking

[0158] Place the continuously wound adhesive sheet in a room - temperature waste - removing and constant - temperature oven and bake it at 300 °C for 10 min to further remove organic solvents, non - ionic aqueous anti - settling agents, and solvent oil, thus obtaining the adhesive sheet.

[0159] The preparation method of a copper - clad laminate containing the above - mentioned adhesive sheet specifically includes the following steps:

[0160] Cut the adhesive sheet, perform lamination and double - sided copper cladding (18unHTE Luxembourg BF - NN - HT), and then perform hot - pressing forming through a vacuum high - temperature oil press. Keep the vacuum state, and hold the pressure for 2 h under the conditions of a maximum material temperature of 385 °C and a pressure of 850 N / cm 2 to obtain the copper - clad laminate.

[0161] Example 7

[0162] The resin composition includes raw materials with the following weights: ceramic powder (10 kg of spherical silica (Suzhou JinYi Q200), 60 kg of hollow - sphere silica (Zhengzhou Shenglaite HS75)) 70 kg, modified polytetrafluoroethylene emulsion with a solid content of 60% (Zhonghao Chenguang SFN - 1, PFA Daikin AW - 1000G) 35 kg, non - ionic aqueous anti - settling agent (Jiangxi Yisheng PEG - 600) 4 kg, organic solvents (Sinopharm anhydrous ethanol with a purity of ≥99.7%, Sinopharm KH570) 28 kg, and solvent oil (Japan's Idemitsu IP2028) 16 kg.

[0163] The preparation method of the above - mentioned resin composition specifically includes the following steps:

[0164] (1) Vacuum mixing

[0165] Add the modified polytetrafluoroethylene emulsion to the non - ionic aqueous anti - settling agent, mix evenly, and then add the ceramic powder through an automatic vacuum feeding machine. Mix in a vacuum mixer for 4 h to reach a uniform suspension state to obtain a preliminary mixture.

[0166] (2) Demulsification and resinification

[0167] Add solvent oil to the initial mixture and mix evenly. Then, while stirring, add an organic solvent. After stirring and mixing for 2 minutes, demulsify to obtain the resin composition.

[0168] The preparation method of the adhesive sheet containing the above resin composition specifically includes the following steps:

[0169] (1) Short-time drying

[0170] Place the resin composition in a constant-temperature degreasing oven and dry it at 150°C for 30 minutes to remove the organic solvent and most of the non-ionic aqueous anti-settling agent, obtaining the dried resin composition;

[0171] (2) Sheet extrusion

[0172] Pour the dried resin composition into a pre-pressing machine to pre-press it into a cylindrical shape, and then place it in an extruder. Extrude a continuously rewound film with a width of 20 cm and a thickness of 5 mm through a heating cavity and a sheet base die orifice;

[0173] (3) Rolling into sheets

[0174] Continuously roll the continuously rewound film into sheets through a two-roll mill. The temperature of the opposing rolls is 100°C to obtain a continuously rewound adhesive sheet with a width of 46 cm and a thickness of 0.070 mm;

[0175] (4) Low-temperature baking

[0176] Place the continuously rewound adhesive sheet in a normal-temperature waste-removing constant-temperature oven and bake it at 300°C for 10 minutes to further remove the organic solvent, non-ionic aqueous anti-settling agent, and solvent oil, obtaining the adhesive sheet.

[0177] The preparation method of the copper-clad laminate containing the above adhesive sheet specifically includes the following steps:

[0178] Cut the adhesive sheet, perform lamination and double-sided copper cladding (18unHTE Luxembourg BF-NN-HT), and then perform hot pressing and forming through a vacuum high-temperature oil press. Maintain the vacuum state, and keep the pressure for 2 hours under the conditions of a maximum material temperature of 385°C and a pressure of 850 N / cm 2 to obtain the copper-clad laminate.

[0179] Example 8

[0180] The adhesive sheet prepared in Example 1 (thickness 0.070 mm) was treated with a plasma processor at an ambient temperature of 100 °C, then subjected to sodium treatment for double-sided activation. A thermosetting hydrocarbon resin was coated with a coater. Using the formulated resin glue of the high-frequency hydrocarbon copper-clad laminate GT3330(L) sold by Chenzhou Gongtian Electronic Ceramic Technology Co., Ltd., it was double-sided coated in the coater at 135 °C / 2 min / 1 m for drying to a thickness of 0.200 mm (Combination A). The above-prepared (Combination A) was double-sided copper-clad (18 unHTE Luxembourg BF-NN-HT), and then hot-pressed and formed through a vacuum high-temperature oil press. While maintaining the vacuum state, at a maximum material temperature of 275 °C and a pressure of 680 N / cm 2 The pressure holding time was 5 h under the conditions, and a thin 0.150 mm double-sided copper-clad laminate was obtained. Two pieces of the obtained double-sided copper-clad laminate were used as core boards, and (Combination A) was laminated in the middle and then laminated to obtain a 4-layer coreless copper-clad laminate for high frequency.

[0181] Example 9

[0182] The coated glue in Example 8 was replaced with the formulated resin glue of the high-speed polyphenylene ether PPO copper-clad laminate GTM70(L) sold by Chenzhou Gongtian Electronic Ceramic Technology Co., Ltd. It was double-sided coated in the coater at 170 °C / 4 min / 1 m for drying to a thickness of 0.180 mm (Combination B). The above-prepared (Combination B) was double-sided copper-clad (18 unHTE Luxembourg BF-NN-HT), and then hot-pressed and formed through a vacuum high-temperature oil press. While maintaining the vacuum state, at a maximum material temperature of 220 °C and a pressure of 650 N / cm 2 The pressure holding time was 2 h under the conditions, and a thin 0.150 mm double-sided copper-clad laminate was obtained. Two pieces of the obtained double-sided copper-clad laminate were used as core boards, and (Combination B) was laminated in the middle and then laminated to obtain a 4-layer coreless copper-clad laminate for high speed.

[0183] Comparative Example 1

[0184] The difference from Example 1 is only that no non-ionic aqueous anti-settling agent is added.

[0185] Comparative Example 2

[0186] The difference from Example 1 is only that no organic solvent is added.

[0187] Comparative Example 3

[0188] The difference from Example 1 is only that no solvent oil is added.

[0189] Comparative Example 4

[0190] The difference from Example 1 is only that the dosage of spherical silica is replaced with 65 kg and the dosage of the modified polytetrafluoroethylene emulsion is replaced with 20 kg.

[0191] Comparative Example 5

[0192] It is only different from Example 1 in that the dosage of spherical silica is replaced with 40 kg and the dosage of modified polytetrafluoroethylene emulsion is replaced with 45 kg.

[0193] Comparative Example 6

[0194] It is only different from Example 8 in that GT3330(L) hydrocarbon resin glue is used, Tianqin Low Dk glass cloth 2116RC52% adopts the impregnation sizing process, a single-layer laminated double-sided copper clad laminate is used, and hot pressing is carried out through a vacuum high-temperature oil press, maintaining the vacuum state, at the highest material temperature of 275 °C and a pressure of 680 N / cm 2 Under the condition of a holding pressure time of 5 h, a double-sided copper clad laminate with a thickness of 0.150 mm is prepared.

[0195] Comparative Example 7

[0196] It is only different from Example 8 in that GTM70(L) polyphenylene ether resin glue is used, Tianqin Low Dk glass cloth 2116RC49% adopts the impregnation sizing process, a single-layer laminated double-sided copper clad laminate is used, and then hot pressing is carried out through a vacuum high-temperature oil press, maintaining the vacuum state, at the highest material temperature of 220 °C and a pressure of 650 N / cm 2 Under the condition of a holding pressure time of 2 h, a double-sided copper clad laminate with a thickness of 0.150 mm is prepared.

[0197] Performance Test

[0198] 1. Take the copper clad laminates prepared in Examples 1-7 and Comparative Examples 1-5 respectively, and test their thickness, peel strength, copper-containing solder dipping, dielectric constant, dielectric loss, thermal expansion coefficient, water absorption rate, reflow soldering, thermal conductivity and inner surface respectively.

[0199] Among them, the specific test methods are as follows:

[0200] 1. Thickness is measured using a micrometer thickness detector.

[0201] 2. Peel strength is measured according to the method specified in IPC-TM-650, 2.4.8.

[0202] 3. Copper-containing solder dipping is measured according to the method specified in IPC-TM-650, 2.4.24.13.

[0203] 4. Dielectric constant is measured using the SPDR (splite post dielectric resonator) method at 1 GHz and 10 GHz.

[0204] 5. Dielectric loss. The SPDR (split post dielectric resonator) method is used to measure the dielectric loss at 10 GHz.

[0205] 6. Coefficient of thermal expansion. The method specified in IPC-TM-650 2.4.41 is used for measurement. The Z coefficient of thermal expansion is selected for analysis at 50 - 260 °C.

[0206] 7. Water absorption rate. The method specified in IPC-TM-650 2.6.2.1 is used for measurement.

[0207] 8. Reflow soldering. The copper-containing samples are passed through the reflow soldering production line, and the set conditions are 80 °C / 30 min, 150 °C / 30 min, 240 °C / 30 min, and 280 °C / 30 min.

[0208] 9. Thermal conductivity. The method specified in ASTM C518 is used for measurement.

[0209] 10. Inner surface. Visual inspection and magnifying glass.

[0210] The test results are shown in Table 1.

[0211] Table 1 Test results of copper clad laminates of Examples 1 - 7 and Comparative Examples 1 - 5

[0212]

[0213] As can be seen from Table 1, by comparing Examples 1 - 6, when fibrous ceramic filling is selected and the filler ratio is 65%, a coefficient of thermal expansion with Z (50 - 260 °C) close to zero can be achieved. When it is 75%, a negative coefficient of thermal expansion can be achieved, and there is great application space when paired with a positive coefficient adhesive sheet. By comparing Example 7, it can be seen that when fibrous ceramic filling is not used, the coefficient of thermal expansion increases significantly. By comparing Example 1 and Comparative Example 1, when non-ionic anti-settling agent is not used, the coefficient of thermal expansion of the prepared sample becomes larger and uneven, and there are color difference defects. In Comparative Example 2, without using organic solvent, rapid demulsification cannot be achieved and demulsification resinification cannot be realized. In Comparative Example 3, without using solvent, oil pressure rolling cracking occurs and thinning cannot be achieved. In Comparative Example 4, too high a ceramic filler ratio will lead to defects such as non-formability and powder dropping. In Comparative Example 5, too low a ceramic filler ratio will lead to an increase in the coefficient of thermal expansion. The above components and ratios need to be used in combination and have a synergistic effect, and none of them can be missing.

[0214] 2. Copper clad laminates prepared from Examples 8 - 9 and Comparative Examples 6 - 7 are each taken, and their thickness, DF, peel strength, and interlayer peel are respectively tested.

[0215] The test results are shown in Table 2.

[0216] Table 2 Test results of copper clad laminates of Examples 8 - 9 and Comparative Examples 6 - 7

[0217]

[0218] As can be seen from Table 2, the coreless double-sided copper clad laminates prepared in Examples 8-9 have lower dielectric loss DF and no difference in peel strength. The prepared double-sided activated substrates can be used to replace glass cloth in high-frequency and high-speed materials to achieve low transmission loss.

[0219] According to the above results, substrates and FCCLs with a thickness of less than 0.050 mm can be fabricated using the present invention. Moreover, the ultra-thin copper clad laminates prepared with the combined ratio of the present invention have a coefficient of thermal expansion tending to zero and low-loss characteristics within the range of 50-260 °C. By replacing glass cloth in high-frequency and high-speed materials, low-loss ultra-thin coreless copper clad laminates can be obtained, and coreless substrates can be laminated to fabricate multi-layer copper clad laminates, which can meet the different application scenarios and higher requirements of future high-frequency and high-speed transmission systems for printed circuit boards.

[0220] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the broadest scope consistent with the principles and novel features disclosed herein.

Claims

1. A resin composition, characterized in that The invention comprises the following raw materials in parts by weight: 65-75 parts of ceramic powder, 25-35 parts of modified polytetrafluoroethylene emulsion, 0.3-5 parts of non-ionic water-based anti-settling agent, 15-55 parts of organic solvent and 10-25 parts of solvent oil.

2. A resin composition according to claim 1, characterized in that, The ceramic powder is at least one of silicon nitride, boron nitride, aluminum oxide, silicon dioxide, titanium dioxide, strontium titanate, barium strontium titanate, barium titanium silicate, rare earth and negative expansion coefficient material; The structure of the ceramic powder is angular, flake, spherical, spherical agglomerates, hollow spherical, fibrous or sponge-like ceramic powder; the sphericity of the sphere is ≥95%, and the particle size is 0.001-15 μm; The modified polytetrafluoroethylene emulsion is at least one of polytetrafluoroethylene emulsion, polytetrafluoroethylene suspension resin powder, polytetrafluoroethylene dispersion resin powder, fluorinated ethylene propylene copolymer, soluble polytetrafluoroethylene and polyimide, and has a solid content of 60%; The non-ionic water-based anti-settling agent is at least one of polyethylene glycol, polyethylene glycol laurate, polyurethane and cellulose derivatives; The organic solvent is at least one of isopropyl ketone, butanone, acetone, anhydrous ethanol and γ-methacryloxypropyltrimethoxysilane; The solvent oil is at least one of odorless kerosene, white oil, isoparaffin and aviation kerosene.

3. A method for preparing the resin composition according to claim 1 or 2, characterized in that: The specific steps include: (1) Vacuum mixing Add modified polytetrafluoroethylene emulsion to non-ionic water-based anti-settling agent, mix evenly, then add ceramic powder, mix in vacuum to achieve uniform suspension state, and obtain primary mixed material; (2) Demulsification and resinification Add solvent oil to the primary mixture and mix evenly, then add organic solvent while stirring, stir and mix to break the emulsion, and then obtain the resin composition.

4. The method for preparing a resin composition according to claim 3, characterized in that: In step (1), the vacuum mixing time is 1-4 hours; In step (2), the stirring, mixing and demulsification time is 1-3 minutes.

5. An adhesive sheet, characterized in that: Contains the resin composition according to claim 1 or 2.

6. A method for preparing the adhesive sheet as claimed in claim 5, characterized in that: The specific steps include: (1) Short-time drying The resin composition is dried for a short time to remove the organic solvent and most of the non-ionic water-based anti-settling agent to obtain a dried resin composition; (2) Sheet extrusion The dried resin composition is pre-pressed into a cylindrical shape and extruded into a sheet to obtain a film that can be continuously rolled up; (3) Rolling into sheets The continuously rewindable film is continuously rolled into a sheet to obtain a continuously rewindable adhesive sheet; (4) Low temperature baking The continuously reelable adhesive sheet is baked at low temperature to further remove the organic solvent, the non-ionic water-based anti-settling agent and the solvent oil, thereby obtaining the adhesive sheet.

7. The method for preparing an adhesive sheet according to claim 6, characterized in that: In step (1), the temperature of the short-time drying is 90-150° C. and the time is 30 min; In step (2), the continuously reelable film has a width of 10-30 cm and a thickness of 1-5 mm; In step (3), the temperature of the rollers for continuously rolling the sheet is 50-150° C.; the width of the continuously rewindable adhesive sheet is 45-55 cm, and the thickness is 0.038-0.200 mm; In step (4), the baking temperature is 160-300° C., and the baking time is 3-10 min; and the thickness of the adhesive sheet is 0.070-0.200 mm.

8. A copper clad laminate, characterized in that: Contains the adhesive sheet according to claim 5.

9. A method for preparing a copper clad laminate as claimed in claim 8, characterized in that: The specific steps include: The adhesive sheet is cut, laminated and copper-clad on both sides or both sides of the laminate are covered with resin sheets and then copper-clad, and vacuum high-temperature oil-pressed to obtain the copper-clad board.

10. The method for preparing a copper clad laminate according to claim 9, characterized in that: The resin sheet is at least one of polytetrafluoroethylene resin film, polyperfluoroethylene propylene resin film, tetrafluoroethylene-perfluoroalkoxy vinyl ether copolymer resin film, polytetrafluoroethylene double-sided modified film, polyimide resin film, polybutadiene resin coating film and polyphenylene ether resin coating film; the maximum material temperature of the vacuum high-temperature oil pressure molding is 200-395°C, and the pressure is 500-1000N / cm 2 , the pressure holding time is 1-3h.

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