CN112708166A - Conductive foam material for electromagnetic shielding and preparation method thereof - Google Patents
Conductive foam material for electromagnetic shielding and preparation method thereof Download PDFInfo
- Publication number
- CN112708166A CN112708166A CN202011621163.3A CN202011621163A CN112708166A CN 112708166 A CN112708166 A CN 112708166A CN 202011621163 A CN202011621163 A CN 202011621163A CN 112708166 A CN112708166 A CN 112708166A
- Authority
- CN
- China
- Prior art keywords
- solution
- electromagnetic shielding
- foam material
- conductive foam
- aluminum carbide
- 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
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J9/00—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
- C08J9/36—After-treatment
- C08J9/40—Impregnation
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2367/00—Characterised by the use of polyesters obtained by reactions forming a carboxylic ester link in the main chain; Derivatives of such polymers
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2375/00—Characterised by the use of polyureas or polyurethanes; Derivatives of such polymers
- C08J2375/04—Polyurethanes
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2401/00—Characterised by the use of cellulose, modified cellulose or cellulose derivatives
- C08J2401/02—Cellulose; Modified cellulose
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K3/00—Use of inorganic substances as compounding ingredients
- C08K3/10—Metal compounds
- C08K3/14—Carbides
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K3/00—Use of inorganic substances as compounding ingredients
- C08K3/16—Halogen-containing compounds
Abstract
The invention discloses a conductive foam material for electromagnetic shielding and a preparation method thereof, wherein flame-retardant sponge is soaked in titanium aluminum carbide composite solution and then dried in a dryer to obtain the conductive foam material for electromagnetic shielding.
Description
Technical Field
The invention belongs to the technical field of conductive foam materials, and particularly relates to a conductive foam material for electromagnetic shielding and a preparation method thereof.
Background
The conductive foam is an EMI material with good shielding performance, in use, EVA or PE foam is usually taken as a base material to wrap conductive cloth, and after a series of treatments, the conductive foam has good surface conductivity, can be easily fixed on a device to be shielded by an adhesive tape, and has different section shapes, installation methods, UL grades and shielding materials with shielding performance to be selected. The product is widely applied to electronic and electric products, mechanical parts, various small household appliances, mobile phone accessories, industrial instruments, computers and peripheral equipment, automobile accessories, audio and video equipment, toys, cosmetics and the like.
The preparation method of the prior conductive foam comprises the following steps: the sponge is coated by a flexible conductive film, and the conductive powder is added during sponge preparation, the sponge at the middle part of the conductive foam prepared by coating the sponge with the flexible conductive film is non-conductive, and the conductive sponge added with the conductive powder during sponge preparation has large resistance and cannot meet the requirement of high conductivity, so that a conductive foam material is needed to be provided, which can meet the requirement of conductivity and has ideal electromagnetic shielding effect.
Disclosure of Invention
The invention aims to make up the defects of the prior art and provides a conductive foam material for electromagnetic shielding and a preparation method thereof.
In order to achieve the above object, the present invention provides the following technical solutions:
a preparation method of a conductive foam material for electromagnetic shielding comprises the steps of dipping flame-retardant sponge into titanium aluminum carbide composite solution, and drying in a dryer to obtain the conductive foam material for electromagnetic shielding.
Further, the flame-retardant sponge material is selected from polyether ester or polyurethane, and the density is 20-70kg/m3The PPI is 30-80.
Furthermore, the flame-retardant sponge is continuously extruded and dipped for 5-10 times in the dipping process, so that the sponge is completely adsorbed and saturated.
Further, the flame-retardant sponge is subjected to heat preservation for 60-120 minutes at 80-120 ℃ in a nitrogen atmosphere during drying.
Further, the titanium aluminum carbide composite solution is prepared from the following raw materials in parts by weight: 1-4 parts of titanium aluminum carbide powder, 1-4 parts of lithium fluoride, 25-100 parts of powdery cellulose, a proper amount of 37% hydrochloric acid solution, a proper amount of 65% sulfuric acid solution and a proper amount of water.
Further, the preparation method of the titanium aluminum carbide composite solution comprises the following steps:
(1) mixing titanium aluminum carbide powder with lithium fluoride, adding a 37% hydrochloric acid solution with the mass being 20-25 times that of the titanium aluminum carbide powder, etching at normal temperature for 24-48 hours, then ultrasonically stripping for 1-3 hours, and centrifuging to remove the un-etched part after etching is finished to obtain a solution A for later use;
(2) immersing the powdery cellulose in a 65% sulfuric acid solution with the mass 6-10 times of that of the powdery cellulose, carrying out acidolysis for 30-60 minutes at 40-50 ℃, then adding water to stop the acidolysis, standing for 12-24 hours, centrifuging to collect a milky white solution, and dialyzing until the liquid outside the bag is nearly neutral to obtain a solution B for later use;
(3) and mixing the solution A and the solution B, and stirring until the solution A and the solution B are uniformly dispersed to obtain the titanium-aluminum carbide composite solution.
Preferably, the ultrasonic power in the step (1) is 400-600W, and the frequency is 35-50 KHz.
Preferably, the centrifugation speed in the step (1) is 3000-4000 rpm, and the time is 1-2 hours.
The invention also provides a conductive foam material for electromagnetic shielding, which is prepared by the preparation method of the conductive foam material for electromagnetic shielding.
The invention has the advantages that:
the conductive foam material takes the flame-retardant sponge as a substrate, and is soaked in the titanium aluminum carbide composite solution to realize the lap joint with the material with the conductive and shielding functions, wherein the titanium aluminum carbide composite solution takes the titanium aluminum carbide as a raw material, after an aluminum layer is etched by lithium fluoride, titanium atoms exposed up and down can be connected by taking a large amount of fluoride ions and hydroxide ions in the solution as ligands to form a stable bonding structure, and the bonding structure has a two-dimensional nano structure similar to graphene, so that the conductive foam material has extremely excellent conductivity.
The conductive foam material has an ideal electromagnetic shielding effect, when electromagnetic waves enter the surface of the material, the electromagnetic waves are immediately reflected due to the existence of a large number of carriers on the surface after titanium aluminum carbide etching, and the residual electromagnetic waves are attenuated continuously under the action of multiple scattering and interface polarization between the sheet layers in the material under the action of induced dipoles generated by surface functional groups, so that the electromagnetic shielding effect is realized.
The preparation process of the conductive foamed cotton material is simple and easy to operate, the obtained product has excellent conductivity, an ideal electromagnetic shielding effect and stable overall performance, the phenomena of material falling and chipping caused by easy and weak bonding and weak adsorption of the traditional foamed cotton material are not easy to occur in the using process, and the conductive foamed cotton material has good use value.
Detailed Description
The technical scheme of the invention is further explained by combining the specific examples as follows:
example 1
A method for preparing conductive foam material for electromagnetic shielding comprises preparing a material with a density of 45kg/m3And soaking the polyether ester flame-retardant sponge with PPI of 55 in the titanium-aluminum carbide composite solution, continuously extruding and dipping for 7 times to ensure that the sponge is completely adsorbed and saturated, then keeping the temperature of 100 ℃ in a dryer for 90 minutes under the nitrogen atmosphere, and drying to obtain the conductive foamed material for the electromagnetic shielding.
The titanium aluminum carbide composite solution is prepared from the following raw materials in parts by weight: 2 parts of titanium aluminum carbide powder, 2 parts of lithium fluoride, 75 parts of powdery cellulose, a proper amount of 37% hydrochloric acid solution, a proper amount of 65% sulfuric acid solution and a proper amount of water, and the preparation method comprises the following steps:
(1) mixing titanium aluminum carbide powder with lithium fluoride, adding a 37% hydrochloric acid solution with the mass being 20 times that of the titanium aluminum carbide powder, etching at normal temperature for 36 hours, then ultrasonically stripping at 500W and 40KHz for 2 hours, centrifuging at 3500 rpm for 1.5 hours after the completion, and removing the un-etched part to obtain a solution A for later use;
(2) immersing powdery cellulose in 65% sulfuric acid solution with the mass of 8 times, carrying out acidolysis for 45 minutes at 45 ℃, then adding water to stop acidolysis, standing for 18 hours, centrifuging to collect milky white solution, and dialyzing until the liquid outside the bag is nearly neutral to obtain solution B for later use;
(3) and mixing the solution A and the solution B, and stirring until the solution A and the solution B are uniformly dispersed to obtain the titanium-aluminum carbide composite solution.
Example 2
A method for preparing conductive foam material for electromagnetic shielding comprises preparing a material with a density of 20kg/m3And soaking the polyurethane flame-retardant sponge with PPI of 30 in the titanium-aluminum carbide composite solution, continuously extruding and dipping for 5 times to ensure that the sponge is completely adsorbed and saturated, then keeping the temperature of 80 ℃ in a dryer for 120 minutes under the atmosphere of nitrogen, and drying to obtain the conductive foamed material for the electromagnetic shielding.
The titanium aluminum carbide composite solution is prepared from the following raw materials in parts by weight: 1 part of titanium aluminum carbide powder, 1 part of lithium fluoride, 25 parts of powdery cellulose, a proper amount of 37% hydrochloric acid solution, a proper amount of 65% sulfuric acid solution and a proper amount of water, and the preparation method comprises the following steps:
(1) mixing titanium aluminum carbide powder with lithium fluoride, adding a 37% hydrochloric acid solution with the mass being 20 times that of the titanium aluminum carbide powder, carrying out normal-temperature etching for 24 hours, then carrying out ultrasonic stripping for 3 hours at 400W and 35KHz, centrifuging for 2 hours at 3000 rpm after completion, and removing the un-etched part to obtain a solution A for later use;
(2) immersing powdery cellulose in a 65% sulfuric acid solution with the mass 6 times that of the powdery cellulose, carrying out acidolysis for 60 minutes at 40 ℃, then adding water to stop the acidolysis, standing for 12 hours, centrifuging to collect a milky solution, and dialyzing until the liquid outside the bag is nearly neutral to obtain a solution B for later use;
(3) and mixing the solution A and the solution B, and stirring until the solution A and the solution B are uniformly dispersed to obtain the titanium-aluminum carbide composite solution.
Example 3
A method for preparing conductive foam material for electromagnetic shielding comprises preparing a material with a density of 70kg/m3And soaking the polyurethane flame-retardant sponge with PPI of 80 in the titanium-aluminum carbide composite solution, continuously extruding and dipping for 10 times to ensure that the sponge is completely adsorbed and saturated, then keeping the temperature of 120 ℃ in a dryer for 60 minutes under the atmosphere of nitrogen, and drying to obtain the conductive foamed material for the electromagnetic shielding.
The titanium aluminum carbide composite solution is prepared from the following raw materials in parts by weight: 4 parts of titanium aluminum carbide powder, 4 parts of lithium fluoride, 92 parts of powdery cellulose, a proper amount of 37% hydrochloric acid solution, a proper amount of 65% sulfuric acid solution and a proper amount of water, and the preparation method comprises the following steps:
(1) mixing titanium aluminum carbide powder with lithium fluoride, adding a 37% hydrochloric acid solution with the mass being 25 times that of the titanium aluminum carbide powder, carrying out normal-temperature etching for 48 hours, then carrying out ultrasonic stripping for 1 hour at 600W and 50KHz, centrifuging for 1 hour at 4000 rpm after completion, and removing the un-etched part to obtain a solution A for later use;
(2) immersing powdery cellulose in a 65% sulfuric acid solution with the mass being 10 times that of the powdery cellulose, carrying out acidolysis for 30 minutes at 50 ℃, then adding water to stop the acidolysis, standing for 24 hours, centrifuging to collect a milky solution, and dialyzing until the liquid outside the bag is nearly neutral to obtain a solution B for later use;
(3) and mixing the solution A and the solution B, and stirring until the solution A and the solution B are uniformly dispersed to obtain the titanium-aluminum carbide composite solution.
Comparative example
Compared with the embodiment 1, the sponge matrix is prepared by adopting a hydroelectric nickel plating mode, and the preparation method comprises the following specific steps:
a method for preparing conductive foam material with a density of 20kg/m3And the PPI is 30 polyurethane flame-retardant sponge, the sponge is plated with conductive nickel in vacuum by adopting a winding magnetron sputtering film plating machine, and the vacuum plating parameters are as follows: pre-pumping background pressure: 1.5X 10-2pa, working operating pressure: 0.25pa, flow of argon: 360SCCM, argon pressure: 0.3Mpa, planar rectangular single target sputtering power: 10Kw, linear speed of operation: 3.5m/min, planar rectangular nickel target purity: not less than 99.95%, surface resistance of vacuum nickel layer: and (3) less than or equal to 0.5k omega, and then carrying out hydroelectric nickel plating on the sponge after vacuum coating, rinsing in a three-stage countercurrent manner, and drying at 160 ℃.
The products obtained in examples 1 to 3 and comparative example were tested for electrical conductivity and electromagnetic wave shielding effect using an RTS-8 four-probe tester, and electromagnetic wave shielding effect using a vector network analyzer N5247A, with the results shown in table 1:
TABLE 1
From the above table, it can be seen that, compared with the conventional conductive foam material adopting the nickel plating method, the conductive foam material of the present invention has more excellent conductive performance and electromagnetic shielding performance.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (9)
1. A preparation method of a conductive foam material for electromagnetic shielding is characterized in that flame-retardant sponge is soaked in a titanium aluminum carbide composite solution and then dried in a dryer to obtain the conductive foam material for electromagnetic shielding.
2. The method for preparing conductive foam material for electromagnetic shielding according to claim 1, wherein the flame-retardant sponge material is selected from polyether ester or polyurethane, and has a density of 20-70kg/m3The PPI is 30-80.
3. The method for preparing the conductive foam material for electromagnetic shielding according to claim 1, wherein the titanium aluminum carbide composite solution is prepared from the following raw materials in parts by weight: 1-4 parts of titanium aluminum carbide powder, 1-4 parts of lithium fluoride, 25-100 parts of powdery cellulose, a proper amount of 37% hydrochloric acid solution, a proper amount of 65% sulfuric acid solution and a proper amount of water.
4. The method for preparing the conductive foam material for electromagnetic shielding according to claim 3, wherein the method for preparing the titanium aluminum carbide composite solution comprises the following steps:
(1) mixing titanium aluminum carbide powder with lithium fluoride, adding a 37% hydrochloric acid solution with the mass being 20-25 times that of the titanium aluminum carbide powder, etching at normal temperature for 24-48 hours, then ultrasonically stripping for 1-3 hours, and centrifuging to remove the un-etched part after etching is finished to obtain a solution A for later use;
(2) immersing the powdery cellulose in a 65% sulfuric acid solution with the mass 6-10 times of that of the powdery cellulose, carrying out acidolysis for 30-60 minutes at 40-50 ℃, then adding water to stop the acidolysis, standing for 12-24 hours, centrifuging to collect a milky white solution, and dialyzing until the liquid outside the bag is nearly neutral to obtain a solution B for later use;
(3) and mixing the solution A and the solution B, and stirring until the solution A and the solution B are uniformly dispersed to obtain the titanium-aluminum carbide composite solution.
5. The method for preparing a conductive foam material for electromagnetic shielding as claimed in claim 4, wherein the ultrasonic power in step (1) is 400-600W, and the frequency is 35-50 KHz.
6. The method as claimed in claim 4, wherein the centrifugation speed in step (1) is 3000-4000 rpm for 1-2 hours.
7. The method for preparing a conductive foam material for electromagnetic shielding according to claim 1, wherein the flame-retardant sponge is continuously dipped and extruded 5-10 times during the dipping process, so that the sponge is completely adsorbed and saturated.
8. The method for preparing a conductive foam material for electromagnetic shielding according to claim 1, wherein the flame retardant sponge is dried and is kept at 80-120 ℃ for 60-120 minutes in a nitrogen atmosphere.
9. An electromagnetic shielding conductive foam material, which is prepared by the method for preparing the electromagnetic shielding conductive foam material according to any one of claims 1 to 8.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011621163.3A CN112708166A (en) | 2020-12-31 | 2020-12-31 | Conductive foam material for electromagnetic shielding and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011621163.3A CN112708166A (en) | 2020-12-31 | 2020-12-31 | Conductive foam material for electromagnetic shielding and preparation method thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN112708166A true CN112708166A (en) | 2021-04-27 |
Family
ID=75547505
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011621163.3A Pending CN112708166A (en) | 2020-12-31 | 2020-12-31 | Conductive foam material for electromagnetic shielding and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112708166A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114230853A (en) * | 2022-01-06 | 2022-03-25 | 常德力元新材料有限责任公司 | Hole type flame-retardant conductive shielding material and preparation method thereof |
| CN114806008A (en) * | 2022-04-01 | 2022-07-29 | 华南理工大学 | Metallocene polypropylene composite material with high crystallization temperature and preparation method thereof |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006152129A (en) * | 2004-11-30 | 2006-06-15 | Nakajima Kogyo:Kk | Electromagnetic wave-shielding film and sheet |
| CN106987020A (en) * | 2017-04-21 | 2017-07-28 | 唐林元 | A kind of preparation method of shielding conducting foam |
| CN109897343A (en) * | 2019-04-11 | 2019-06-18 | 西北工业大学 | A kind of MXene aeroge/epoxy resin electromagnetic shielding nanocomposite and preparation method thereof |
| CN110358136A (en) * | 2019-07-04 | 2019-10-22 | 武汉纺织大学 | A kind of composite foam film and preparation method thereof |
| CN111286078A (en) * | 2018-12-07 | 2020-06-16 | 中国科学院大连化学物理研究所 | Flexible conductive MXene-based foam and preparation method thereof |
| CN111592684A (en) * | 2020-05-29 | 2020-08-28 | 陕西科技大学 | Preparation method of isolated thermoplastic elastomer composite microporous electromagnetic shielding material |
-
2020
- 2020-12-31 CN CN202011621163.3A patent/CN112708166A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006152129A (en) * | 2004-11-30 | 2006-06-15 | Nakajima Kogyo:Kk | Electromagnetic wave-shielding film and sheet |
| CN106987020A (en) * | 2017-04-21 | 2017-07-28 | 唐林元 | A kind of preparation method of shielding conducting foam |
| CN111286078A (en) * | 2018-12-07 | 2020-06-16 | 中国科学院大连化学物理研究所 | Flexible conductive MXene-based foam and preparation method thereof |
| CN109897343A (en) * | 2019-04-11 | 2019-06-18 | 西北工业大学 | A kind of MXene aeroge/epoxy resin electromagnetic shielding nanocomposite and preparation method thereof |
| CN110358136A (en) * | 2019-07-04 | 2019-10-22 | 武汉纺织大学 | A kind of composite foam film and preparation method thereof |
| CN111592684A (en) * | 2020-05-29 | 2020-08-28 | 陕西科技大学 | Preparation method of isolated thermoplastic elastomer composite microporous electromagnetic shielding material |
Non-Patent Citations (1)
| Title |
|---|
| 车如心: "《界面与胶体化学》", 31 August 2012 * |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114230853A (en) * | 2022-01-06 | 2022-03-25 | 常德力元新材料有限责任公司 | Hole type flame-retardant conductive shielding material and preparation method thereof |
| CN114230853B (en) * | 2022-01-06 | 2023-01-17 | 常德力元新材料有限责任公司 | Hole type flame-retardant conductive shielding material and preparation method thereof |
| CN114806008A (en) * | 2022-04-01 | 2022-07-29 | 华南理工大学 | Metallocene polypropylene composite material with high crystallization temperature and preparation method thereof |
| CN114806008B (en) * | 2022-04-01 | 2023-12-22 | 华南理工大学 | Metallocene polypropylene composite material with high crystallization temperature and preparation method thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN112708166A (en) | Conductive foam material for electromagnetic shielding and preparation method thereof | |
| CA3076401A1 (en) | Nickel-plated carbon fiber film, manufacturing method of nickel-plated carbon fiber film, shielding structure and preparation method of shielding structure | |
| CN112094573B (en) | Sprayable efficient electromagnetic shielding slurry and preparation method thereof | |
| CN106793727A (en) | A kind of electromagnetic shielding film and preparation method thereof | |
| CN107354752B (en) | Surface-coated silver F-12 conductive fiber and preparation method thereof | |
| CN101469075B (en) | Method for preparing two-sided polyimide / silver compound film | |
| CN106397825A (en) | Graphene-based three-dimensional porous electromagnetic shielding material suitable for high-temperature humid environment | |
| CN111613367B (en) | Polyurethane cross-linked reduced graphene oxide composite conductive film and preparation method and application thereof | |
| CN103642039A (en) | Wood-based polyaniline electromagnetic shielding material and manufacture method thereof | |
| KR100935185B1 (en) | Method for manufacturing textile coated with conductive metal | |
| EP0140664B1 (en) | Radio wave shielding materials and a method of producing the same | |
| CN107626917B (en) | Preparation method of silver-plated copper powder | |
| CN105754512A (en) | Non-bright, anti-fingerprint and scraping-resistant single-side adhesive tape for conductive fabric and preparation method | |
| US2973502A (en) | Integral cable and connector | |
| CN1705045A (en) | Technological process for preparing flexible conducting material by vacuum sputtering | |
| CN205751550U (en) | A kind of all-directional conductive sponge | |
| CN103434210A (en) | Preparation method of high molecular material-metal film composite conducting stably | |
| CN107452433A (en) | A kind of all-directional conductive sponge and preparation method thereof | |
| CN103980827B (en) | The conductive communication method of conductive tape, electrical equipment and electric appliance casing, earthing method | |
| CN109760398B (en) | Combination mode of high-frequency copper-clad plate fluorine-containing resin prepreg | |
| CN112852010B (en) | High-shielding composite conductive sponge material and preparation method thereof | |
| CN110149790B (en) | Graphene electromagnetic shielding film and preparation method thereof | |
| CN1324161C (en) | Preparation method of non-conductive plastic surface metal membrane | |
| CN108384177B (en) | Four-phase double-percolation electromagnetic shielding material and preparation method thereof | |
| KR101965610B1 (en) | High frequency noise shielding film and method for manufacturing the same |
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 | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20210427 |
|
| RJ01 | Rejection of invention patent application after publication |