High-strength antioxidant inductance glue for bonding superfine soft magnetic powder

Abstract

The invention discloses high-strength anti-oxidation inductance glue for bonding superfine soft magnetic powder, relates to the field of electronic component materials, and aims to provide anti-oxidation inductance glue which is high in curing strength, excellent in insulating property and capable of uniformly coating the surface of the superfine metal soft magnetic powder. The technical scheme provided by the invention comprises the following components in parts by weight: 80-100 parts of epoxy resin, 5-20 parts of nano silicon dioxide powder, 1-10 parts of a coupling agent, 1-10 parts of a wetting agent, 5-15 parts of a dispersing agent, 1-15 parts of an antioxidant, 3-30 parts of a curing agent and 100-200 parts of an organic solvent. According to the scheme, eddy-current loss can be effectively reduced, and the use efficiency of the inductor is improved.

Description

Technical Field

[0001] The invention relates to the field of electronic component materials, in particular to a high-strength anti-oxidation inductor glue for bonding ultrafine soft magnetic powder. Background Art

[0002] With the rapid development of third-generation semiconductors, new energy, and next-generation communications technologies, the demand for high-frequency applications in electronic devices has expanded dramatically, placing higher demands on the high-frequency performance of soft magnetic materials. Soft magnetic materials and related devices play a vital role in energy storage, conversion, and transmission. One-piece molded inductors, an upgraded version of wound inductors, feature a coil embedded within a soft magnetic composite core. They are experiencing explosive growth due to their small size, stable structure, high efficiency, and excellent current and saturation current characteristics. In recent years, AI chips have been rapidly moving towards high performance and power. As a core component, chip inductors are facing unprecedented technological challenges. One-piece inductors are trending towards miniaturization, high frequency, high current, and low loss. To effectively minimize inductor losses at high frequencies, ultra-fine soft magnetic metal powder is used to reduce eddy current losses within the magnetic powder particles. After an insulation and passivation treatment, the powder is coated with an organic or inorganic binder to minimize direct contact between the powder particles and reduce eddy current losses. However, introducing too much non-magnetic material during the insulation coating and binder addition process increases the hysteresis loss of the soft magnetic material. Furthermore, ultra-fine soft magnetic metal powders are more susceptible to oxidation in high-temperature air, resulting in a decrease in magnetic properties and increased losses. Therefore, in actual use, it is necessary to maintain inductance strength while reducing the amount of glue used to improve the glue's insulation properties. Furthermore, the glue must be evenly coated on the surface of the soft magnetic metal powder, isolating the powder particles from each other and further preventing oxidation.

[0003] Traditional inductor glue is mainly composed of epoxy / phenolic resin, curing agent and solvent. Due to the huge density difference between glue and soft magnetic powder, the soft magnetic powder is prone to agglomeration during the mixing process with the glue. The smaller the soft magnetic powder particles, the more likely they are to agglomerate.

[0004] Therefore, there is an urgent need for an anti-oxidation inductor glue that has high curing strength, excellent insulation performance, and can be evenly coated on the surface of ultrafine metal soft magnetic powder. Summary of the Invention

[0005] In view of the problems existing in the traditional inductor glue system in the above background, the present invention provides a high-strength and antioxidant inductor glue preparation solution that can be used in the field of electronic components. This solution can effectively reduce eddy current loss and improve the utilization efficiency of the inductor.

[0006] In order to achieve the above-mentioned purpose, the technical solution of the present invention comprises, by weight, 80-100 parts of epoxy resin, 5-20 parts of nano-silica powder, 1-10 parts of coupling agent, 1-10 parts of wetting agent, 5-15 parts of dispersant, 1-15 parts of antioxidant, 3-30 parts of curing agent, and 100-200 parts of organic solvent.

[0007] The preparation method is as follows: an organic solvent, a high-functionality epoxy resin, a coupling agent, a wetting agent, a dispersant and an antioxidant are added to a stirring container, and a stirring reaction is started at room temperature (about 60 minutes). After the reaction is completed and the solution is clarified, nano-silica is added and stirred at room temperature (about 60 minutes). Finally, a curing agent is added and stirring is continued. After the reaction is completed, the solution is sealed and refrigerated to obtain a high-strength antioxidant inductor glue.

[0008] High-functionality epoxy resin and nano-silica powder are mixed in a specific ratio, and then a coupling agent, a wetting agent, a dispersant, an antioxidant, a curing agent and an organic solvent are added in sequence to form a homogeneous mixture.

[0009] The epoxy resin is a compound of one or more of bisphenol A epoxy resin, dicyclopentadiene o-cresol resin, and tetraglycidylamine epoxy resin; Bisphenol A epoxy resin Dicyclopentadiene o-cresol resin Tetraglycidylamine type epoxy resin (Ag-80). The particle size of the nano-silicon dioxide powder is less than 30 nm; The coupling agent is a combination of one or more silane coupling agents or phthalate coupling agents with amino groups or long-chain fatty alkyl groups; The wetting agent is a combination of one or more polyoxyethylene fatty alcohol derivatives or alkyl sulfate derivatives; The dispersant is a combination of one or more of polyacrylamide derivatives, sodium dodecylbenzenesulfonate or oleyl amino oleate; The above antioxidant is a sterically hindered phenolthiadiazole derivative; Antioxidant.

[0010] The curing agent is a compound of one or more aromatic diamine curing agents or imidazole curing agents; The organic solvent is a mixture of one or more of acetone, ethanol and toluene.

[0011] The advantages of this patent are: (1) The bisphenol A epoxy resin and dicyclopentadiene o-cresol resin in the adhesive component have a high epoxy value, and their cured products have excellent curing strength, which can ensure the strength of the inductor shell at a lower usage amount.

[0012] (2) The tetraglycidylamine epoxy resin in the adhesive component is liquid at room temperature. Adding it to the solid resin can improve the compressibility of the soft magnetic powder, which is beneficial to increasing the density during the inductive pressing process, reducing the proportion of non-magnetic materials, and reducing hysteresis loss.

[0013] (3) Nano-silicon dioxide powder is added to the composition to reduce the contact probability between soft magnetic powders, reduce eddy current loss between powder particles, increase air gap, and improve DC bias characteristics.

[0014] (4) The addition of a coupling agent to the composition improves the adhesion of the resin to the soft magnetic powder and nano-silica powder, allowing the adhesive to be evenly coated on the substrate, especially for metal powders.

[0015] (5) The composition is added with a wetting agent, which can improve the wetting effect of the solid-liquid interface. By reducing the surface tension of the liquid and the interfacial tension between the solid and the liquid, the liquid can spread on the surface of the solid material or penetrate its surface, thereby wetting the solid material.

[0016] (6) A dispersant is added to the composition and is adsorbed on the particle surface by physical (such as van der Waals forces, hydrogen bonds, electrostatic interactions) or chemical (strong chemical bonds, such as covalent bonds or ionic bonds) means, thereby maintaining a distance between the particles and reducing the tendency of uncontrolled flocculation, mainly through electrostatic repulsion or steric hindrance. The wetting agent and the dispersant work synergistically to improve the uniformity of the mixture during mechanical stirring, so that the resin is fully, completely, and evenly distributed on the surface of the soft magnetic powder particles.

[0017] (7) Antioxidants are added to the composition to prevent the metal from reacting with oxygen in the air and causing corrosion.

[0018] (8) The curing agent in the composition can satisfy the requirement that the glue has a high strength after curing. DETAILED DESCRIPTION

[0019] The technical solutions of the present invention are described clearly and completely below through specific embodiments. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0020] Example 1 Take 150 parts of acetone, 50 parts of bisphenol A epoxy resin, 40 parts of tetraglycidylamine epoxy resin, 7 parts of silane coupling agent KH-550, 10 parts of polyoxyethylene fatty alcohol derivatives, 15 parts of polyacrylamide derivatives, and 3 parts of hindered phenol thiadiazole derivatives and add them into a stirring container in sequence. Stir at room temperature for 60 minutes. After the solution is clarified, add 10 parts of nano-silica and stir at room temperature for 60 minutes. Finally, add 10 parts of 4,4'-diaminodiphenylmethane and stir for 20 minutes. After stirring, seal and refrigerate to obtain high-strength antioxidant inductor glue.

[0021] Silane coupling agent KH-550.

[0022] Example 2 Take 150 parts of acetone, 50 parts of dicyclopentadiene o-cresol resin, 40 parts of tetraglycidylamine type epoxy resin, 7 parts of silane coupling agent, 10 parts of alkyl sulfate derivatives, 15 parts of oleyl amino oleate, and 3 parts of hindered phenol thiadiazole derivatives, and add them into a stirring container respectively. Stir at room temperature for 60 minutes. After the solution is clarified, 10 parts of nano-silica is added and stirred at room temperature for 60 minutes. Finally, 3 parts of dimethylimidazole are added and stirred for 20 minutes. After stirring, it is sealed and refrigerated to obtain a high-strength antioxidant inductor glue.

[0023] Example 3 Take 150 parts of acetone, 20 parts of dicyclopentadiene o-cresol resin, 30 parts of bisphenol A epoxy resin, 40 parts of tetraglycidylamine epoxy resin, 7 parts of titanate coupling agent, 10 parts of polyoxyethylene fatty alcohol derivatives, 15 parts of polyacrylamide derivatives, and 3 parts of hindered phenol thiadiazole derivatives and add them into a stirring container in sequence. Stir at room temperature for 60 minutes. After the solution is clarified, add 10 parts of nano-silica and stir at room temperature for 60 minutes. Finally, add 20 parts of 4,4'-diaminodiphenyl sulfone and 1 part of dimethylimidazole and stir for 20 minutes. After stirring, seal and refrigerate to obtain high-strength antioxidant inductor glue.

[0024] When using, add 5 parts of the glue prepared in Examples 1-3 directly to 100 parts of D 50 = 5μm carbonyl iron powder, mechanically stirred for 10 minutes, taken out and made into particles with a diameter of less than 60 mesh using a mechanical granulator, and the residual solvent was dried in an oven. 3g of the granulated powder was pressed into a magnetic ring with an inner diameter of 6mm and an outer diameter of 20mm using a 20-ton press, and then placed in a 200℃ oven for 1 hour. The following tests were performed: the breaking strength of the magnetic ring was tested using a ZT-825S tensile testing machine; Use TH2683A insulation withstand voltage tester to measure the insulation resistance of the magnetic ring at 100V; Use HYN-60 salt spray corrosion test chamber to measure the rust resistance of magnetic ring (coating uniformity evaluation); The magnetic ring loss was measured using a SY-8218 BH analyzer.

[0025] The test results are as follows: The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. High-strength, anti-oxidation inductor glue for bonding ultra-fine soft magnetic powder, characterized by: The glue is prepared from epoxy resin, nano silicon dioxide powder, coupling agent, wetting agent, dispersant, antioxidant, curing agent and organic solvent in the following weight ratio of 80-100:5-20:1-10:1-10:5-15:1-15:3-30:100-200.

2. The high-strength, anti-oxidation inductor glue for bonding ultrafine soft magnetic powder according to claim 1, characterized in that: The epoxy resin is one or more of bisphenol A epoxy resin, dicyclopentadiene o-cresol resin and tetraglycidylamine epoxy resin.

3. The high-strength, anti-oxidation inductor glue for bonding ultrafine soft magnetic powder according to claim 1, characterized in that: The particle size of the nano silicon dioxide powder is less than 30 nm.

4. The high-strength, anti-oxidation inductor glue for bonding ultrafine soft magnetic powder according to claim 1, characterized in that: The coupling agent is a silane coupling agent with amino group or fatty long-chain alkyl group, and / or a phthalate coupling agent.

5. The high-strength, anti-oxidation inductor glue for bonding ultrafine soft magnetic powder according to claim 1, characterized in that: The wetting agent is a polyoxyethylene fatty alcohol derivative and / or an alkyl sulfate derivative.

6. The high-strength, anti-oxidation inductor glue for bonding ultrafine soft magnetic powder according to claim 1, characterized in that: The dispersant is one or more of polyacrylamide derivatives, sodium dodecylbenzenesulfonate or oleyl amino oleate.

7. The high-strength, anti-oxidation inductor glue for bonding ultrafine soft magnetic powder according to claim 1, characterized in that: The antioxidant is a sterically hindered phenolthiadiazole derivative.

8. The high-strength, anti-oxidation inductor glue for bonding ultrafine soft magnetic powder according to claim 1, characterized in that: The curing agent is an aromatic diamine curing agent and / or an imidazole curing agent.

9. The high-strength, anti-oxidation inductor glue for bonding ultrafine soft magnetic powder according to claim 1, characterized in that: The organic solvent is one or more of acetone, ethanol or toluene.

10. The method for preparing a high-strength, anti-oxidation inductor glue for bonding ultrafine soft magnetic powder according to any one of claims 1 to 9, characterized in that: The preparation method comprises the following steps: adding an organic solvent, a high-functionality epoxy resin, a coupling agent, a wetting agent, a dispersant and an antioxidant into a stirring container, starting a stirring reaction at room temperature, adding nano-silica after the reaction is completed and the solution is clarified, stirring at room temperature, and finally adding a curing agent, continuing to stir, and sealing and refrigerating after the reaction is completed to obtain a high-strength antioxidant inductor glue.

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