CN114007403A - Broadband efficient electromagnetic shielding silver paste and preparation method and application thereof - Google Patents
Broadband efficient electromagnetic shielding silver paste and preparation method and application thereof Download PDFInfo
- Publication number
- CN114007403A CN114007403A CN202111382684.2A CN202111382684A CN114007403A CN 114007403 A CN114007403 A CN 114007403A CN 202111382684 A CN202111382684 A CN 202111382684A CN 114007403 A CN114007403 A CN 114007403A
- Authority
- CN
- China
- Prior art keywords
- silver
- electromagnetic shielding
- nano
- silver paste
- broadband
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K9/00—Screening of apparatus or components against electric or magnetic fields
- H05K9/0073—Shielding materials
- H05K9/0081—Electromagnetic shielding materials, e.g. EMI, RFI shielding
Landscapes
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Engineering & Computer Science (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Shielding Devices Or Components To Electric Or Magnetic Fields (AREA)
Abstract
A broadband high-efficiency electromagnetic shielding silver paste and a preparation method and application thereof belong to the technical field of electromagnetic shielding materials. The invention provides a broadband efficient electromagnetic shielding silver paste which comprises, by mass, 30-80% of nano silver, 3-10% of magnetic particles, 1-5% of silver precursor, 0.5-5% of reducing agent, 0.5-3% of resin, 15-65% of solvent and 0-3% of dispersing agent. The invention also provides a preparation method and application of the broadband high-efficiency electromagnetic shielding silver paste. According to the invention, the nano silver and the magnetic particles are compounded, and the magnetic particles and the nano silver are combined through low-temperature sintering of the nano silver, so that the low-frequency shielding efficiency is improved. Meanwhile, a silver source is introduced to generate nano silver in situ, so that the loss of electrical property caused by the introduction of magnetic particles is reduced, and the broadband and efficient shielding coating material is obtained.
Description
Technical Field
The invention belongs to the technical field of electromagnetic shielding materials, and particularly relates to broadband efficient electromagnetic shielding silver paste and a preparation method and application thereof.
Background
With the rapid development of scientific technology and electronic information industry, the popularization and application of various digitalized and high-frequency electronic and electric equipment such as computers, radio communication equipment and the like inject new vitality into the information industry revolution, promote the development of industrial technology and improve the life of people. However, these electronic devices radiate a large amount of electromagnetic waves of different wavelengths and frequencies into space due to rapid voltage changes during operation, and these electromagnetic radiations not only interfere with signal propagation of communications and various electronic systems, but also may cause information leakage in digital transmission systems, posing a threat to national information and security. In addition, the large dose of electromagnetic radiation can also affect the nervous system and the lymphatic system of the human body, so that the human body suffers from nervous diseases and malignant tumors, and the living environment of the human body can be harmed. In this regard, a series of regulations and technical standards have been successively issued by various national and international organizations, such as VDE certification of the german electrical technology association, FCC regulation of the federal communications commission in the united states, electromagnetic wave protection regulation and environmental electromagnetic wave health standards in our country, CISPR standard of the special committee for radio interference, and the like. With the application of electronic equipment, the interference of electromagnetic wave radiation on electrical appliances and electronic equipment is effectively inhibited, and people are increasingly paid more attention to the protection of human beings from the harm of electromagnetic wave radiation, so that the electromagnetic wave radiation-resistant electromagnetic wave shielding material becomes an important task for scientific research and industrial product development.
The most convenient and effective way to suppress electromagnetic radiation is to achieve electromagnetic shielding using shielding materials. The electromagnetic shielding material reflects electromagnetic waves through impedance difference with air and attenuates eddy currents of the electromagnetic waves through self electromagnetic induction. Due to the good electrical conductivity of metallic materials, the most common EMI shielding solution has traditionally been to use a metal cover or cage to cover the target area or component. However, this solution cannot meet the continuously increasing demands for miniaturization (thinner and thinner packages), smaller footprint (footprint) and higher packing density of electronic components. This solution cannot be used in some micro devices, since the metal cover/lid requires too much space. Particularly, with the arrival of the high-frequency and high-speed 5G era and the development of wearable equipment, electronic components are developing towards miniaturization, light weight, digitalization and high-density integration, higher requirements are provided for electromagnetic shielding materials, and the novel shielding material should meet the characteristics of thinness, lightness, width, strength and the like, namely, the shielding material is thin in thickness, light in weight, wide in absorption frequency band and strong in wave absorption capacity under the same conditions. Therefore, research and development of novel electromagnetic shielding materials with high efficiency, easy use and high cost performance become key elements for treating space pollution and improving living environment. In the face of increasing social demands, the novel efficient electromagnetic shielding material has very remarkable social and economic benefits.
In recent years, in order to meet the ultra-thin requirement of the product and keep the same with the ultra-thin thickness of the product, the new generation of conformal shielding technology is increasingly emphasized. The leading technology for preparing the ultrathin shielding layer in the industry at present is mainly realized by three processes of sputtering, electroplating and spraying. The sputtering technique is a technique of bombarding the surface of a plating material with charged particles in a vacuum chamber to deposit the bombarded particles on a substrate. The prepared coating has uniform density, strong bonding force with a base material, controllable film thickness and good repeatability, but the target material has low utilization rate, complex equipment and high cost. In addition, the conformal shielding film prepared by the technology in the SIP package structure has some problems, such as poor bonding with EMC; the limited sidewall coating results in low coverage (< 50%), which may lead to poor shield grounding and reliable performance; at present, uniform sputtering of ferromagnetic targets cannot be realized, and the low-frequency shielding effect is low; low processing speed, low mass production efficiency and the like. The plating technique is a technique of forming a plating layer by depositing cations of a pre-plated metal in a plating solution on a substrate surface by electrolysis using a metal to be plated as a cathode in a salt solution containing the pre-plated metal. The method is not limited by the shape and size of the base material, the coating is uniform and has strong adhesive force, and the method can be used for batch production and has low cost. The disadvantage is that the varieties of plastics suitable for electroplating are few, and the plastics must be subjected to special activation and sensitization treatment before electroplating. More critically, the process requires soaking the SIP device in an electrolyte, which may increase the potential for later failure of the device. Further, the plating technique is not recognized due to environmental requirements and the like. The spray coating technique is a coating technique in which a liquid is atomized into a mist by an air flow of compressed air and sprayed on the surface of an object to form a thin film. Compared with the two technologies, the technology has the advantages of relatively low capital investment, simple and convenient operation, good coating quality, high coating efficiency and the like. The conformal shielding process can flexibly meet various requirements of a single-layer chip, and has excellent adhesive property and reliability, simple and clean process and low investment cost. Therefore, the technology is considered to be an attractive solution, which is concerned and favored by back-end application manufacturers.
The traditional electromagnetic shielding paste is mainly additive type, namely prepared by compounding polymer and conductive powder. For example, Chinese patent CN2917207 discloses an environment-friendly conductive material for electromagnetic shielding, which is prepared by compounding low-bulk-ratio flaky composite metal conductive powder with polymer film-forming resin and the like to prepare a shielding coating with the thickness of 8-15 mu m, wherein the electrical sheet resistance of the shielding coating is 150m omega/□. The method can only make the electrical property of the prepared coating reach 10 due to the existence of the polymer-4～10-5And the shielding requirement of the SiP package cannot be met. Subsequently, CN102321402A discloses a transparent conductive ink composed of organic amine or ammonia water as solvent and organic silver salt, wherein a surfactant or an adhesive is added according to the affinity and adhesiveness of the substrate when the conductive ink is used, and then the conductive ink is heated and cured at 90-200 ℃ to obtain a conductive circuit. Although the method does not need to add a protective agent, organic amine or ammonia water is adopted as a solvent, and organic silver salt and the like need to be prepared in advance, so that the method is complex and the stability of the organic silver salt is poor; in addition, fatty alcohol or other substances are added to adjust the viscosity of the ink according to the characteristics of different substrates during use, so that the ink is inconvenient to use and has poor bonding force with the substrates, and the addition of the substances still has the defects of influence on the final conductivity and poor surface flatness of the wires. CN104140717A discloses a high-solid-content spray printing conductive ink with good dispersibility and high stability, which can be sintered at low temperature and has conductivity reaching 9.1-40.2 m omega/□ after molding, but because the high-molecular-weight viscosity regulator used in the system is hydrophilic resin, the adhesion capability and the humidity and heat resistance performance of the high-molecular-weight viscosity regulator cannot reach the use standard of the electronic industry. CN202010995743.2 discloses a sprayable high-efficiency electromagnetic shielding slurry, which has better covering and adhesive force to SiP chips and devices, the shielding effectiveness of the material per se reaches more than 85dB, the shielding effectiveness is more than 35dB at a near field of 100 MHz-6 GHz,however, the shielding effectiveness below 100MHz is still insufficient and needs to be further improved.
Disclosure of Invention
Aiming at the problems existing in the prior art, namely EMI interference around and in a System In Package (SiP), and the requirement of a spraying scheme on high conductivity, high magnetic conductivity, broadband high shielding efficiency and high reliability of shielding paste, the invention aims to design and provide the broadband high-efficiency electromagnetic shielding silver paste and the preparation method and application thereof. According to the invention, the nano silver and the magnetic particles are compounded, and the nano silver is sintered at a low temperature, so that the combination of the nano magnetic particles and the nano silver is realized, and the low-frequency shielding efficiency is improved. Meanwhile, a silver source is introduced to generate nano silver in situ, so that the loss of electrical property caused by the introduction of magnetic particles is reduced, the broadband and efficient shielding coating material is obtained, the adhesive force can reach 5B, the contact resistance is less than 12m omega, the shielding efficiency of low frequency 10MHz reaches 23dB, the shielding efficiency of 100MHz near field is greater than 38dB, and the shielding efficiency of 500 MHz-6 GHz near field is greater than 45 dB.
In order to achieve the purpose, the invention adopts the following technical scheme:
the broadband efficient electromagnetic shielding silver paste is characterized by comprising the following components in percentage by mass:
30-80% of nano silver;
3-10% of magnetic particles;
1 to 5 percent of silver precursor
0.5 to 5 percent of reducing agent
0.5-3% of resin;
15-65% of a solvent;
0.0-3% of a dispersant.
The broadband high-efficiency electromagnetic shielding silver paste is characterized in that the nano silver is one or more of a sheet shape, a spherical shape or a similar spherical shape, a cube shape, a triangular shape and a rod shape, and is preferably a sheet shape; the size of the nano silver is 2-100 nm, and the preferable size is 10-60 nm.
The broadband high-efficiency electromagnetic shielding silver paste is characterized in that the magnetic particles comprise one or more of nano nickel powder, nano silver coated nickel, nano carbonyl iron powder, rare earth cerium/neodymium doped ferrite nano powder, nano nickel coated multi-walled carbon nanotubes and silver/nickel/cobalt coated nano silicon carbide, and preferably the magnetic particles are rare earth cerium/neodymium doped ferrite nano powder and nano silver coated nickel.
The broadband efficient electromagnetic shielding silver paste is characterized in that the silver precursor comprises one or more of silver nitrate, silver acetate, silver oxalate, silver isobutyrate and silver neodecanoate, and preferably the silver precursor is silver acetate and silver oxalate.
The broadband efficient electromagnetic shielding silver paste is characterized in that the reducing agent comprises one or more of formic acid, acetaldehyde, benzaldehyde, ethylene glycol, ascorbic acid, glucose, triethanolamine, sodium citrate trihydrate and p-dimethylaminobenzaldehyde, and preferably the reducing agent is ethylene glycol or glucose.
The broadband high-efficiency electromagnetic shielding silver paste is characterized in that the resin comprises one or more of methyl cellulose, ethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, cellulose acetate, acrylic resin, polyurethane resin and polyester, and preferably the resin is ethyl cellulose or cellulose acetate.
The broadband efficient electromagnetic shielding silver paste is characterized in that the solvent comprises at least one of ethanol, isopropanol, butanol, acetone, butanone, cyclohexanone, tetrahydrofuran, toluene, xylene, diethylbenzene, terpineol, propylene glycol methyl ether, propylene glycol ethyl ether, diethylene glycol methyl ether, dipropylene glycol methyl ether, diethylene glycol ethyl ether, dipropylene glycol butyl ether, diethylene glycol dimethyl ether, dipropylene glycol dimethyl ether, ethylene glycol phenyl ether, propylene glycol methyl ether acetate, propylene glycol butyl ether acetate, triethylene glycol monomethyl ether, ethylene glycol methyl ether acetate and ethylene glycol ethyl ether acetate, and the preferable solvent is terpineol or propylene glycol methyl ether acetate.
The broadband efficient electromagnetic shielding silver paste is characterized in that the dispersing agent is one or more of BYK-110, BYK-111, BYK182, BYK190, BYK W9010 and TEGO900, and the preferable dispersing agent is BYK-110 or BYK W9010.
The preparation method of the broadband high-efficiency electromagnetic shielding silver paste is characterized by comprising the following steps of:
(1) weighing the following raw materials in percentage by mass: 30-80% of nano silver, 3-10% of magnetic particles, 1-5% of silver precursor, 0.5-5% of reducing agent, 0.5-3% of resin, 15-65% of solvent and 0-3% of dispersing agent;
(2) dissolving the resin and the silver precursor in the step (1) in the solvent, uniformly dispersing by ultrasonic, adding the dispersing agent, and stirring at room temperature for ultrasonic dispersion for 20-40 min;
(3) sequentially adding the magnetic particles, the nano silver and the reducing agent in the step (1) and uniformly mixing to obtain a mixed material;
(4) and (4) grinding, filtering and defoaming the mixed material obtained in the step (3) to obtain the broadband high-efficiency electromagnetic shielding silver paste.
The broadband high-efficiency electromagnetic shielding silver paste is applied to an electromagnetic shielding material.
Compared with the prior art, the invention realizes the shielding requirements of different frequency bands by selecting the compounding and formula design of multiple functional particles and adopting a one-time spraying process, and has the following beneficial effects:
(1) according to the invention, nano-silver is selected as a medium-high frequency main shielding material, and through the surface contact and low-temperature sintering welding characteristics of the nano-sheets, the contact resistance among particles is reduced, the construction of a high-efficiency conductive network is realized, and the high-performance shielding requirement of a medium-high frequency band of 500 MHz-6 GHz is maintained; meanwhile, the nano magnetic particles with high magnetic conductivity and wave absorbing property are introduced, the shielding performance of a low-frequency band of 10-100 MHz is effectively improved by coating and doping rare earth elements, and the broadband shielding after multi-component packaging can be realized by a one-step spraying process.
(2) In order to overcome the construction of the magnetic particles on the conductive network, the invention also introduces a silver precursor into the system, realizes the connection between the nano magnetic particles and the nano silver through in-situ reduction and synchronous sintering processes, further strengthens the formation of the conductive network, improves the conductivity of the composite shielding coating, and has important significance for preparing the ultrathin, wide-band and high-performance electromagnetic shielding material.
(3) The broadband electromagnetic shielding silver paste obtained by the invention has the conductivity of 5.9-8.6 multiplied by 10 after being cured-6(omega cm), the adhesive force is 5B, the near field shielding effectiveness reaches 23-25 dB at 10MHz, 37-40 dB at 100MHz, and the shielding effectiveness is more than 49dB at 500 MHz-3 GHz.
Detailed Description
To better illustrate the invention and to facilitate the understanding of the technical solutions thereof, typical but non-limiting examples of the invention are as follows:
it should be noted that the silver nanoparticles of the present invention are directly purchased from Jiangsu Xiancheng nanomaterial science and technology company Limited (XFJ78) and Suzhou cryolite nanomaterial science and technology company Limited (CST-NF-S150); the magnetic nanoparticles are respectively purchased from NiAg-GB0301, NiAg-Kyoto Bo-Shi New materials science and technology Co., Ltd, NanBaofensite powder, Shanghai Special Nannocteria science and technology Co., Ltd, silver-coated silicon carbide, etc.; the acrylic resin is purchased from Shanghai general chemical engineering (SK6528) ethanol, ethylene glycol, propylene glycol methyl ether acetate, terpineol, toluene, glucose, silver oxalate, silver neodecanoate, p-dimethylaminobenzaldehyde, ethyl cellulose, acetate fiber and the like in the following examples are analytically pure, and are purchased from Aladdin reagent GmbH, silver nitrate and analytically pure are purchased from national medicine reagents.
Example 1:
a broadband high-efficiency electromagnetic shielding silver paste comprises the following components in percentage by mass:
nano silver CST-NF-S150: 70g
Neodymium-doped ferrite powder: 15g of
Silver oxalate: 6g
Glucose: 2g
Ethylene glycol: 6g
Ethyl cellulose: 3g
Terpineol: 25g of
Propylene glycol methyl ether acetate: 35g of
BYK-110：2g。
The preparation method of the broadband high-efficiency electromagnetic shielding silver paste comprises the following steps:
s1, adding 3g of ethyl cellulose, 6.0g of silver oxalate and 2.0g of BYK110 into 25g of terpineol and 35g of propylene glycol methyl ether acetate, and ultrasonically dispersing for 30min to uniformly disperse the mixture.
S2, sequentially adding 15g of neodymium-doped ferrite powder, 70g of CST-NF-S150 nano silver, 2g of glucose and 6g of ethylene glycol, and uniformly mixing to obtain a mixed material.
And S3, grinding, filtering and defoaming the mixed material to obtain the broadband efficient electromagnetic shielding silver paste 1.
Example 2:
the broadband efficient electromagnetic shielding silver paste comprises the following components in percentage by mass:
nano silver CST-NF-S150: 80g of
Silver-coated nickel NiAg-GB 0301: 8g
Silver oxalate: 2g
Triethanolamine: 1g
Ethylene glycol: 3g
Ethyl cellulose: 3g
Terpineol: 15g of
Propylene glycol methyl ether acetate: 45g of
BYK-110：1.5g。
The preparation method of the broadband efficient electromagnetic shielding silver paste comprises the following steps:
s1, adding 3g of ethyl cellulose, 2.0g of silver oxalate and 1.5g of BYK110 into 15g of terpineol and 45g of propylene glycol methyl ether acetate, and ultrasonically dispersing for 30min to uniformly disperse the mixture.
S2, sequentially adding 80g of CST-NF-S150 nano silver, 8g of NiAg-GB0301 silver-coated nickel nano powder, 1g of triethanolamine and 3g of ethylene glycol, and uniformly mixing to obtain a mixed material.
And S3, grinding, filtering and defoaming the mixed material to obtain the broadband high-efficiency electromagnetic shielding silver paste 2.
Example 3:
the broadband efficient electromagnetic shielding silver paste comprises the following components in percentage by mass:
nano silver XFJ 78: 90g
Silver-coated nickel powder NiAg-GB 0301: 5g
Silver-coated silicon carbide: 5g
Silver neodecanoate: 4g
Ethylene glycol: 5g
Cellulose acetate: 4g
Toluene: 30g of
Terpineol: 15g of
Propylene glycol methyl ether acetate: 25g of
Butanol: 10g
BYK-182：2.0g。
The preparation method of the broadband efficient electromagnetic shielding silver paste comprises the following steps:
s1, firstly, adding 4g of cellulose acetate, 4.0g of silver neodecanoate and 2g of BYK182 into 30g of toluene, 15g of terpineol, 10g of butanol and 25g of propylene glycol methyl ether acetate, and ultrasonically dispersing for 30min to uniformly disperse the mixture.
S2, sequentially adding 5g of NiAg-GB0301 silver-coated nickel nano powder, 5g of silver-coated silicon carbide, 90g of XFJ78 nano silver and 5g of ethylene glycol, and uniformly mixing to obtain a mixed material.
And S3, grinding, filtering and defoaming the mixed material to obtain the broadband high-efficiency electromagnetic shielding silver paste 3.
Example 4:
the broadband efficient electromagnetic shielding silver paste comprises the following components in percentage by mass:
nano silver CST-NF-S150: 100g
Silver-coated nickel NiAg-GB 0301: 6g
Lanthanum-doped barium ferrite powder: 9g of
Silver neodecanoate: 5g
Ethylene glycol: 6g
Cellulose acetate: 5g
Terpineol: 15g of
Toluene: 30g of
Butanol: 10g
Propylene glycol methyl ether acetate: 25g of
BYK-W9010：2.0g。
The preparation method of the broadband efficient electromagnetic shielding silver paste comprises the following steps:
s1, firstly, adding 5g of cellulose acetate, 5.0g of silver neodecanoate and 2g of BYK-W9010 into 30g of toluene, 15g of terpineol, 10g of butanol and 25g of propylene glycol monomethyl ether acetate, and ultrasonically dispersing for 30min to uniformly disperse the mixture.
S2, sequentially adding 6g of NiAg-GB0301 silver-coated nickel nano powder, 9g of lanthanum-doped barium ferrite powder, 100g of CST-NF-S150 nano silver and 6g of glycol, and uniformly mixing to obtain a mixed material;
and S3, grinding, filtering and defoaming the mixed material to obtain the broadband high-efficiency electromagnetic shielding silver paste 4.
Example 5:
the broadband efficient electromagnetic shielding silver paste comprises the following components in percentage by mass:
nano silver CST-NF-S150: 100g
Silver-coated nickel NiAg-GB 0301: 12g of
Silver nitrate: 3g
P-dimethylaminobenzaldehyde: 3g
Acrylic resin SK 6528: 5g
Terpineol: 25g of
Ethanol: 35g of
Ethylene glycol: 5g
Propylene glycol methyl ether acetate: 15g of
TEGO900：1.5g。
The preparation method of the broadband efficient electromagnetic shielding silver paste comprises the following steps:
s1, firstly, 5gSK6528 acrylic resin, 3.0g of silver nitrate and 1.5g of TEGO900 are added into 25g of terpineol, 35g of ethanol, 5g of ethylene glycol and 15g of propylene glycol methyl ether acetate to be ultrasonically dispersed for 30min, so that the mixture is uniformly dispersed.
S2, sequentially adding 12g of silver-coated nickel nano powder, 100g of CST-NF-S150 nano silver and 3g of p-dimethylaminobenzaldehyde, and uniformly mixing to obtain a mixed material;
and S3, grinding, filtering and defoaming the mixed material to obtain the broadband efficient electromagnetic shielding silver paste 5.
Performance testing
The electromagnetic shielding slurry prepared in the examples and comparative examples was subjected to the following performance tests:
(1) determination of adhesion
The adhesion was tested according to the requirements specified in GB9286-98 "test for marking out paint films of paints and varnishes".
(2) Determination of volume resistivity
The volume resistance of the conductive shielding film was tested as required by the requirements specified in ASTM D2739-1997 test method for bulk resistivity of conductive adhesives.
(3) Determination of Shielding Properties
The near field shielding performance is tested by using a testing system consisting of a SmartScan-350-EMI electromagnetic interference scanning analyzer and an N5230C network analyzer to carry out shielding effectiveness test on the shielding coating, wherein the testing range is 10 MHz-3 GHz.
The test results and conditions are shown in table 1:
TABLE 1 Performance test of electromagnetic shielding pastes obtained in examples 1 to 5 and comparative examples 1 to 2
Comparing the examples 1-5 with the commercial imported product performance test, it can be seen from table 1 that the shielding effectiveness of the examples 1-5 at 10MHz is 3-5 dB higher than that of the commercial imported product EMI8880S, which indicates that the introduction of the magnetic particles into the electromagnetic shielding silver paste formulation can enhance the shielding effectiveness of low frequency. Meanwhile, the shielding effectiveness of the medium and high frequency of 500 MHz-3 GHz is also improved to a certain extent. Therefore, the technical scheme disclosed by the invention can obtain the ultrathin broadband high-efficiency shielding coating and meet the requirements of conformal shielding of system-level packaging devices and PCB boards.
While preferred embodiments of the present invention have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. Therefore, it is intended that the appended claims be interpreted as including preferred embodiments and all such alterations and modifications as fall within the scope of the invention.
It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.
Claims (10)
1. The broadband efficient electromagnetic shielding silver paste is characterized by comprising the following components in percentage by mass:
30-80% of nano silver;
3-10% of magnetic particles;
1 to 5 percent of silver precursor
0.5 to 5 percent of reducing agent
0.5-3% of resin;
15-65% of a solvent;
0-3% of a dispersant.
2. The broadband high-efficiency electromagnetic shielding silver paste according to claim 1, wherein the nano silver is one or more of a sheet shape, a spherical shape or a spherical-like shape, a cube shape, a triangular shape and a rod shape, preferably a sheet shape; the size of the nano silver is 2-100 nm, and the preferable size is 10-60 nm.
3. The broadband high-efficiency electromagnetic shielding silver paste as claimed in claim 1, wherein the magnetic particles comprise one or more of nano nickel powder, nano silver coated nickel, nano carbonyl iron powder, rare earth cerium/neodymium doped ferrite nano powder, nano nickel coated multi-walled carbon nanotube, and silver/nickel/cobalt coated nano silicon carbide, and preferably the magnetic particles are rare earth cerium/neodymium doped ferrite nano powder and nano silver coated nickel.
4. The broadband high-efficiency electromagnetic shielding silver paste according to claim 1, wherein the silver precursor comprises one or more of silver nitrate, silver acetate, silver oxalate, silver isobutyrate and silver neodecanoate, and preferably the silver precursor is silver acetate and silver oxalate.
5. The broadband high-efficiency electromagnetic shielding silver paste according to claim 1, wherein the reducing agent comprises one or more of formic acid, acetaldehyde, benzaldehyde, ethylene glycol, ascorbic acid, glucose, triethanolamine, sodium citrate trihydrate and p-dimethylaminobenzaldehyde, and preferably the reducing agent is ethylene glycol or glucose.
6. The broadband high-efficiency electromagnetic shielding silver paste according to claim 1, wherein the resin comprises one or more of methyl cellulose, ethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, cellulose acetate, acrylic resin, polyurethane resin and polyester, and preferably the resin is ethyl cellulose or cellulose acetate.
7. The broadband high-efficiency electromagnetic shielding silver paste as claimed in claim 1, wherein the solvent comprises at least one of ethanol, isopropanol, butanol, acetone, butanone, cyclohexanone, tetrahydrofuran, toluene, xylene, diethylbenzene, ethylene glycol, terpineol, propylene glycol methyl ether, propylene glycol ethyl ether, diethylene glycol methyl ether, dipropylene glycol methyl ether, diethylene glycol ethyl ether, dipropylene glycol ethyl ether, diethylene glycol butyl ether, dipropylene glycol butyl ether, diethylene glycol dimethyl ether, dipropylene glycol dimethyl ether, ethylene glycol phenyl ether, propylene glycol methyl ether acetate, propylene glycol butyl ether acetate, triethylene glycol monomethyl ether, ethylene glycol methyl ether acetate, ethylene glycol ethyl ether acetate, ethylene glycol butyl ether acetate, preferably the solvent is terpineol or propylene glycol methyl ether acetate.
8. The broadband high-efficiency electromagnetic shielding silver paste as claimed in claim 1, wherein the dispersant is one or more of BYK-110, BYK-111, BYK182, BYK190, BYK W9010 and TEGO900, and preferably the dispersant is BYK-110 or BYK W9010.
9. The method for preparing the broadband high-efficiency electromagnetic shielding silver paste according to claims 1-8, comprising the following steps:
(1) weighing the following raw materials in percentage by mass: 30-80% of nano silver, 3-10% of magnetic particles, 1-5% of silver precursor, 0.5-5% of reducing agent, 0.5-3% of resin, 15-65% of solvent and 0-3% of dispersing agent;
(2) dissolving the resin and the silver precursor in the step (1) in the solvent, uniformly dispersing by ultrasonic, adding the dispersing agent, and stirring at room temperature for ultrasonic dispersion for 20-40 min;
(3) sequentially adding the magnetic particles, the nano silver and the reducing agent in the step (1) and uniformly mixing to obtain a mixed material;
(4) and (4) grinding, filtering and defoaming the mixed material obtained in the step (3) to obtain the broadband high-efficiency electromagnetic shielding silver paste.
10. The use of the broadband high-efficiency electromagnetic shielding silver paste of claims 1-8 as an electromagnetic shielding material.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111382684.2A CN114007403A (en) | 2021-11-22 | 2021-11-22 | Broadband efficient electromagnetic shielding silver paste and preparation method and application thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111382684.2A CN114007403A (en) | 2021-11-22 | 2021-11-22 | Broadband efficient electromagnetic shielding silver paste and preparation method and application thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN114007403A true CN114007403A (en) | 2022-02-01 |
Family
ID=79929605
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111382684.2A Pending CN114007403A (en) | 2021-11-22 | 2021-11-22 | Broadband efficient electromagnetic shielding silver paste and preparation method and application thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114007403A (en) |
-
2021
- 2021-11-22 CN CN202111382684.2A patent/CN114007403A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN112094573B (en) | Sprayable efficient electromagnetic shielding slurry and preparation method thereof | |
| CN108192325B (en) | Low-reflection high-shielding electromagnetic shielding composite material with gradient structure and preparation thereof | |
| CN102850885B (en) | Conductive coating used for plastic surface | |
| CN104039121B (en) | One kind inhales waveguide magnetic shield film and preparation method thereof | |
| CN102197718A (en) | Electromagnetic interference suppressing hybrid sheet | |
| CN103756509B (en) | A kind of anti-electromagnetic radiation anti-contamination function coating and preparation method thereof | |
| CN103609207B (en) | electromagnetic wave interference suppressor | |
| CN101781520B (en) | Water-based conducting polymer/metal composite nano-coating for porous wall board and preparation method thereof | |
| CN203233642U (en) | Wave-absorbing magnetic-conductive shielding film with laminated structure | |
| KR100624316B1 (en) | Electroconductive paint composition and electroconductive film prepared therefrom | |
| CN103929933B (en) | Structure for inhibition of electromagnetic wave interference and flexible printed circuit comprising same | |
| CN104854974A (en) | Electromagnetic interference suppression body | |
| CN101950597B (en) | Silver aluminum slurry for electromagnetic shielding and preparation method thereof | |
| CN112341972A (en) | Flexible wave-absorbing material and preparation method thereof, wave-absorbing adhesive tape and preparation method thereof | |
| CN112638143B (en) | Efficient electromagnetic shielding nano silver paste and preparation method thereof | |
| CN112111233A (en) | Thermosetting conductive shielding adhesive film and preparation method thereof | |
| CN105034483A (en) | Shield film having heat-dissipating function | |
| CN112625441B (en) | Manganese-zinc ferrite/polyaniline/titanium carbide composite wave-absorbing material and preparation method thereof | |
| CN114007403A (en) | Broadband efficient electromagnetic shielding silver paste and preparation method and application thereof | |
| KR100455338B1 (en) | Conductive paint composition for shielding a substrate against EMI/RFI | |
| CN110894396A (en) | Shielding paint capable of preventing electromagnetic wave interference and preparation method thereof | |
| CN111154228A (en) | Preparation method of electromagnetic wave shielding film | |
| CN108395807A (en) | A kind of anti-electromagnetic radiation anti-contamination function coating and preparation method thereof | |
| KR100582659B1 (en) | Electrically conductive paint compositions and preparation method thereof | |
| CN109894611B (en) | Chemical plating Cu-Fe-Co-based composite corrosion-resistant wave-absorbing material and preparation method and application thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |