TWI445018B - Electromagnetic shielding composition, electromagnetic shielding device, anti-electrostatic device and method of manufacturing electromagnetic shielding structure - Google Patents

Description

Composition for electromagnetic shielding, electromagnetic shielding device, antistatic device and preparation method of electromagnetic shielding structure

The present disclosure relates to a composition for electromagnetic shielding, and more particularly to a composition having a nanowire and a nanoparticle.

With the advancement of wireless communication technology, wireless communication devices such as mobile phones and the like are widely used. Since the wireless communication device and its base station generate electromagnetic waves, it is easy to cause electromagnetic waves in the environment. In addition, many everyday electronic products, such as computers or microwave ovens, also generate trace amounts of electromagnetic waves.

According to a report published by the World Health Organization in 1998, people who have been exposed to higher than the standard value of electromagnetic waves for a long time are prone to diseases such as cardiovascular disease, diabetes or cancer, or are prone to diseases of the reproductive system, immune system, nervous system, etc., or Cause abortion, abortion or infertility in pregnant women. Long-term exposure to children above the standard value of electromagnetic waves is prone to symptoms such as slow bone development, decreased hematopoietic function, visual decline, and even retinal detachment. It can be seen that electromagnetic waves have a great impact on the health of the human body.

At present, the conventional method of shielding electromagnetic waves is to shield the electromagnetic wave source by using a metal block or a metal casing, but it is not easy to use because it is heavy in weight, difficult to fit with the desired shape, and easily oxidized and damaged under long-term use. All kinds of electronic products.

Another method of shielding electromagnetic waves is to mix metal particles in a colloid or lacquer to form an electromagnetic wave shielding layer on the body in a coating manner. The electromagnetic wave shielding layer is light in weight and can be produced in various shapes. However, in order to achieve a certain degree of electromagnetic wave shielding effect, a high concentration of metal particles needs to be added to the colloid or lacquer. High concentration of metal particles will improve the shielding effect, but will reduce the plasticity and strength of the mixed material, and lose the advantages of easy processing, light weight and low cost. In addition, the electromagnetic wave shielding layer generally only has metal particles of a single outer shape structure, and the content of the metal particles is increased in order to improve the shielding effect, and the improvement of the Shielding Effectiveness (S.E.) is generally limited.

In addition, the conventional electromagnetic wave shielding layer usually needs to be prepared to a thickness of 250 micrometers or more in order to have a significant electromagnetic wave shielding effect. However, the preparation of a thick electromagnetic wave shielding layer is not uniform and wastes a lot of material.

In view of the deficiencies of the conventional method of shielding electromagnetic waves, it is necessary to develop an electromagnetic wave shielding material having the advantages of high electromagnetic shielding rate, low cost, and ease of use.

One embodiment of the present disclosure discloses a composition for electromagnetic shielding comprising a carrier, a plurality of nanowires, and a plurality of nanoparticles. A plurality of nanowires are interspersed in the carrier, wherein the nanowires are between 1 and 95 parts by weight based on 100 parts by weight of the composition. A plurality of nanoparticles are dispersed in the carrier, wherein the nanoparticles are present in an amount of from 0.1 part by weight to 60 parts by weight based on 100 parts by weight of the composition.

Another embodiment of the present disclosure discloses a composition for electromagnetic shielding comprising a carrier, a plurality of nanowires, and a plurality of nanoparticles. A plurality of nanowires are interspersed in the carrier. The nano metal wires have an aspect ratio greater than 10. The nano metal wire is a mixture, alloy or oxide of gold, silver, copper, indium, palladium, aluminum, iron, cobalt, nickel or the foregoing metal, wherein the nano metal is 100 parts by weight of the composition. The wire is between 1 part by weight and 95 parts by weight. A plurality of nanoparticles are interspersed in the carrier. The nanoparticles are less than 1000 nm. The nanoparticle is gold, silver, copper, indium, palladium, aluminum, iron, cobalt, nickel or a mixture, alloy or oxide of the foregoing metals, wherein the nanoparticle is based on 100 parts by weight of the composition. It is from 0.1 part by weight to 60 parts by weight.

Another embodiment of the present disclosure discloses a composition for electromagnetic shielding comprising a carrier, a plurality of nanowires, and a plurality of nanoparticles. A plurality of nanowires are interspersed in the carrier. The nano metal wires have an aspect ratio greater than 10. The nanowire is a mixture, alloy or oxide of gold, silver, copper, indium, palladium, aluminum, iron, cobalt, nickel or the foregoing metals. A plurality of nanoparticles are interspersed in the carrier. The nanoparticles are less than 1000 nm. The nanoparticles are gold, silver, copper, indium, palladium, aluminum, iron, cobalt, nickel or a mixture, alloy or oxide of the foregoing metals. The nano metal wires are between 1 part by weight and 11 parts by weight based on 100 parts by weight of the composition, and the nano particles are between 0.5 parts by weight and 4 parts by weight, so that the combination is used for electromagnetic shielding. The object has an electromagnetic wave shielding efficiency value greater than 10 dB.

Another embodiment of the present disclosure discloses a composition for electromagnetic shielding comprising a carrier, a plurality of nanowires, and a plurality of nanoparticles. A plurality of nanowires are interspersed in the carrier. The nano metal wires have an aspect ratio of 20 to 500. The nanowire is a mixture, alloy or oxide of gold, silver, copper, indium, palladium, aluminum, iron, cobalt, nickel or the foregoing metals. A plurality of nanoparticles are interspersed in the carrier. The nanoparticles have a particle size of 30 to 1000 nm. The nanoparticles are gold, silver, copper, indium, palladium, aluminum, iron, cobalt, nickel or a mixture, alloy or oxide of the foregoing metals. Wherein the nano metal wire is from 1 part by weight to 3 parts by weight based on 100 parts by weight of the composition, and the nano particles are from 0.5 part by weight to 4 parts by weight based on the total weight of the composition, and thus used The composition for electromagnetic shielding has an electromagnetic wave shielding efficiency value greater than 10 dB.

An embodiment of the present disclosure discloses an electromagnetic shielding device including a body and a film, wherein a film is formed on the body to shield electromagnetic waves. The film comprises a plurality of nanowires and a plurality of nanoparticles, wherein a plurality of nanowires and a plurality of nanoparticles are respectively dispersed in the film, and the nanowires are 100 parts by weight of the film. It is between 1 part by weight and 95 parts by weight; the nano particles are between 0.5 parts by weight and 60 parts by weight.

One embodiment of the present disclosure discloses an antistatic device comprising a substrate and a film, wherein a film is formed on the substrate. The film comprises a plurality of nanowires and a plurality of nanoparticles, wherein a plurality of nanowires and a plurality of nanoparticles are respectively dispersed in the film, and the nanowires are 100 parts by weight of the film. Between 1 part by weight and 95 parts by weight; the nanoparticles are between 0.1 part by weight and 60 parts by weight.

The present disclosure further provides a method for preparing an electromagnetic shielding structure, comprising the steps of: providing a target; providing a mixed material, the mixed material comprising a plurality of nanowires, wherein the nanowires have an aspect ratio greater than 50: using the mixed material, forming a first film on one surface of the target; and heating the first film to a temperature between 50 degrees Celsius and 250 degrees Celsius.

One embodiment of the present disclosure discloses a composition for electromagnetic shielding comprising a carrier, a plurality of nanowires, and a plurality of nanoparticles. The plurality of nanowires are dispersed in the carrier; the plurality of nanoparticles are dispersed in the carrier; and the plurality of nanowires and the plurality of nanoparticles are mixed with each other.

In one embodiment, the content of the plurality of nanowires is between 1 part by weight and 95 parts by weight based on 100 parts by weight of the composition, and the plurality of nanoparticles is 100 parts by weight of the composition. The content of the particles is from 0.1 part by weight to 60 parts by weight. In another embodiment, the content of the nanoparticles is from 0.3 parts by weight to 40 parts by weight. In another embodiment, the content of the nanoparticles is from 0.5 parts by weight to 20 parts by weight. In another embodiment, the content of the nanoparticles is from 0.5 part by weight to 10 parts by weight. In another embodiment, the content of the nanoparticles is from 0.5 parts by weight to 4 parts by weight. In another embodiment, the content of the nanoparticles is from 0.5 parts by weight to 2 parts by weight.

In one embodiment, the content of the plurality of nanowires is between 1 part by weight and 95 parts by weight based on 100 parts by weight of the composition, and the plurality of nanoparticles is 100 parts by weight of the composition. The content of the particles is between 0.5 parts by weight and 60 parts by weight.

In one embodiment, the ratio of the plurality of nanowires to the plurality of nanoparticles may be greater than 0.1.

One embodiment of the present disclosure discloses a cured body formed by curing the aforementioned composition. In one embodiment, the aforementioned cured body may be a film on one of the electromagnetic shielding devices or one of the antistatic devices. The nanowire can form a conductive structure such that the cured body can be substantially electrically conductive.

According to the inference, the addition of nano particles can change the optical path difference of the electromagnetic wave, so that the electromagnetic wave energy can be lost in the solidified body, so the mixing of the nano particles into the nano metal wire can significantly improve the electromagnetic shielding efficiency of the solidified body (Shielding Effectiveness; SE ).

The plurality of nano particles disclosed in the present invention may have a particle diameter of less than 1000 nm.

In an embodiment, the nanoparticles can be electrically conductive particles. In another embodiment, the nano particles may be nano metal particles, and the material thereof may be gold, silver, copper, indium, palladium, aluminum, iron, cobalt, nickel or a mixture of the foregoing metals or an alloy of the foregoing or the foregoing An oxide of a metal wherein the nano metal particles are present in an amount of from 0.5 part by weight to 2 parts by weight based on the total weight of the composition. In still another embodiment, the nanoparticles may be gold-coated silver nanoparticles, silver-coated gold nanoparticles, gold-coated copper nanoparticles, copper-coated gold nanoparticles, and silver-coated copper nanoparticles. Particles, copper coated silver nanoparticles or a combination of the foregoing.

In an embodiment, the nanoparticles may be magnetically permeable particles and they may comprise ferromagnetic elements. In another embodiment, the nano particles may be insulating magnetic conductive particles, and the material thereof may include triiron tetroxide, wherein the nano particles may be 0.5 parts by weight to 4 parts by weight based on 100 parts by weight of the composition. Between 0.5 parts by weight and 2 parts by weight.

In one embodiment, the nano particles may be nano silver particles, nano-iron trioxide particles or a mixture of the foregoing particles, wherein the nano particles may be 0.5 parts by weight based on 100 parts by weight of the composition. Between 4 parts by weight or between 0.5 parts by weight and 2 parts by weight.

In one embodiment, the nanoparticles are conductive particles, magnetically permeable particles, insulated magnetically permeable particles, or a combination thereof, and the nanoparticles are between 0.5 parts by weight and 2 parts by weight.

In one embodiment, the nanoparticles may have a particle size greater than 10 nanometers, or such as between 30 nanometers and 1000 nanometers. In one embodiment, the nanoparticles may have a particle size between 30 nanometers and 500 nanometers.

The composition is cured into a solidified body, and the plurality of nanowires are uniformly distributed in the solidified body. In one embodiment, the plurality of nanowires can form a network structure within the cured body such that the cured body has a low surface resistivity, such as less than 10 ohms/square (Ω/sqr).

In another embodiment, the composition comprises a small amount of nanowire metal, and after the composition is cured into a cured body, the plurality of nanowires can form a network structure or a network-like structure in the cured body, wherein the network structure Or a network structure allows the cured body to have a higher surface resistivity value, for example between 10 and 10 ⁶ ohms/square (Ω/sqr).

In still another embodiment, the composition comprises a small amount of nanowires, and after the composition is cured into a cured body, the plurality of nanowires can form a network structure or a network-like structure in the cured body, wherein the network structure Or a network structure allows the cured body to have a high surface resistivity value, for example, between 10 ⁴ and 10 ¹² ohms/square (Ω/sqr), so that the cured body can be used in an antistatic environment. .

The composition may comprise a nano metal wire having a high aspect ratio. The use of high aspect ratio nanowires can greatly increase the electromagnetic shielding efficiency of the cured body. In addition, the use of nanometer metal wires with a high aspect ratio can further reduce the amount of nanowires used.

In an embodiment, the nano metal wires may have an aspect ratio greater than 10, or such as between 20 and 500, or such as between 50 and 300.

In one embodiment, the nanowire may be gold, silver, copper, indium, palladium, aluminum, iron, cobalt, nickel, or a mixture, alloy or oxide of the foregoing. In another embodiment, the nano metal wire may be a gold-coated silver nanowire, a silver-coated gold nanowire, a gold-coated copper nanowire, a copper-coated gold nanowire, or a silver-coated copper nano. Rice wire, copper coated silver nanowire or a combination of the foregoing.

The carrier may comprise a polymeric material. The polymer material may comprise a thermoplastic plastic such as an acrylic resin or a thermosetting plastic such as an epoxy resin. In one embodiment, the carrier may also be a photo-crosslinking or thermally crosslinking polymer material.

The use of a mixed material of a metal or magnetically conductive nanomaterial to form a film on a target allows the target to have an electromagnetic shielding effect. If the film is applied with light energy or heat energy, the electromagnetic shielding efficiency of the film can be further improved. Since the electromagnetic shielding efficiency of the film is improved, the thickness of the film can be reduced without detracting from the shielding effect of the electromagnetic wave required. The reduced thickness allows for a more uniform film and reduces the amount of material used. The film can be heated to a temperature between 50 degrees Celsius and 250 degrees Celsius. The hybrid material may comprise a nano material and a carrier, wherein the carrier may be a polymer material, and the nano material may be a nano metal wire, and the nano metal wires may have an aspect ratio of greater than 50. In one embodiment, the carrier may also be a photo-crosslinking or thermally crosslinking polymer material.

The film can be heated to a temperature between 50 degrees Celsius and 250 degrees Celsius for a period of time (at least 5 minutes or more) to increase the electromagnetic shielding efficiency of the film between 30M and 16G by at least 5dB. In one embodiment, the film is heated for at least 5 minutes at a temperature between 60 degrees Celsius and 250 degrees Celsius. In one embodiment, the heating is for at least 1 hour. In one embodiment, the film is heated at a temperature between 60 degrees Celsius and 200 degrees Celsius for 5 minutes to over 2 hours.

The material of the nano metal wire may be gold, silver, copper, indium, palladium, aluminum, iron, cobalt or nickel. The material of the nano metal wire may also be gold, silver, copper, indium, palladium, aluminum, iron, cobalt, nickel or a mixture of the foregoing metals, or gold, silver, copper, indium, palladium, aluminum, iron, cobalt, Nickel or an oxide of the foregoing metal.

In an embodiment, the film may further comprise a plurality of nano particles, wherein the nano particles are metal nanoparticles, magnetic nanoparticles or a mixture thereof. The metal nanoparticles can be silver particles. The magnetically conductive nanoparticle may be a triiron tetroxide particle. Nanoparticles are less than 1000 nanometers (eg, between 30 nanometers and 1000 nanometers or between 30 nanometers and 500 nanometers). The content of the nanoparticles may be from 0.1 to 60 parts by weight, from 0.3 to 40 parts by weight, from 0.5 to 20 parts by weight, from 0.5 to 4 parts by weight or from 0.5 to 2, based on 100 parts by weight of the film. Between parts by weight.

Two films may be formed on the target, one of which comprises a nanowire and the other film comprises a metal or magnetically conductive nanoparticle.

The target can be determined by the application. For example, when applied to an electronic device, the target may be a housing of the electronic device, a circuit board on the electronic device, or a component on the electronic device that needs electromagnetic shielding. In addition, the target may also be a substrate carrying a film.

Several examples are listed below to explain the disclosure in more detail.

Experimental example 1

The preparation methods described below can be used to formulate combinations of different nanowires and nanoparticles. In each sample, first, a nanowire with a length to diameter ratio greater than 20 was synthesized. The preparation method of the nano silver wire may be a laser ablation method, a metal vapor synthesis method, a chemical reduction method or a polyol method. The foregoing preparation methods are well known to those skilled in the art and will not be described again.

Next, the synthesized nano silver wire and the nanoparticle are added to a polymer material to obtain a composition. The composition can uniformly disperse the nano silver wire and the nano particles in the polymer material by means of an ultrasonic oscillating device and a planetary centrifugal mixer. Then, after the composition is appropriately shaped and cured, a cured body is obtained. Finally, the electromagnetic wave shielding efficiency value of the cured body was tested. The electromagnetic wave shielding efficiency value can be tested by a standard electromagnetic wave testing method, for example, ASTM D4935-99. Generally, the electromagnetic wave shielding efficiency value (S.E.) can be expressed by the following formula.

Wherein, I _in is the electromagnetic wave intensity of the incident test sample; I _out is the electromagnetic wave intensity of the test sample.

Table 1 illustrates six different concentrations of the composition. The composition (sample 1 to sample 5) is the same weight part of nano silver wire (Ag nanowire; AgNW) but different parts by weight of ferroferric oxide particles (Fe ₃ O ₄ nano particle; Fe ₃ O ₄ NP Prepared by mixing into a polymer solution, wherein the content of the nano silver wire is 1.22 parts by weight, and the content of the ferroferric oxide particles is between 0 and 1.88 parts by weight, based on 100 parts by weight of the composition, The above polymer material is ETERSOL 6515 unsaturated polyester resin (Source: ETERNAL CHEMICAL CO., LTD, Taiwan). The polymer material contains a polymethyl methacrylate aqueous solution.

The methyl methacrylate content is about 45 to 55 parts by weight, and the water is about 55 to 45 parts by weight, based on 100 parts by weight of the polymer material. Further, the aforementioned nano silver wire has an aspect ratio of 250, and the ferroferric oxide nanoparticle has a particle diameter of 100 nm. In the sample 6, only the ferroferric oxide particles were mixed into the polymer solution, and the content of the triiron tetroxide particles was 9.09 parts by weight. After the samples 1 to 6 were uniformly mixed, they were respectively prepared into films of 50 μm thickness, and finally the electromagnetic wave shielding ratios of the films were tested.

As shown in Fig. 1 and Fig. 2, it can be found from the test results of the samples 1 to 5 that the efficiency of shielding the electromagnetic wave by the film is also increased substantially as the content of the ferroferric oxide particles increases. When the content of the ferric oxide nanoparticles is between 0.1 and 3 parts by weight, especially between 0.5 and 2 parts by weight, there is a good electromagnetic shielding efficiency value.

Therefore, it can be seen that an appropriate amount of the magnetic conductive particles is added to the film in which the nano metal wire is mixed, and the electromagnetic wave shielding efficiency can be remarkably improved, but when too much magnetic conductive particles are added to the film in which the nano metal wire is mixed, As a result, the more magnetic conductive particles speculated by the prior art, the better the opposite effect. Therefore, when the particle size of the ferroferric oxide nanoparticle is 80 to 120 nm, and the aspect ratio of the nano silver wire is 200 to 300, the content of the triiron tetroxide particles may be between 0.1 and 3 Parts by weight or between 0.5 and 2 parts by weight.

Further, it can be seen from the test results of the sample 6 that although the ferroferric oxide particles are magnetically conductive particles, only a film of 9.09 parts by weight of the ferroferric oxide particles is mixed, and there is little electromagnetic wave shielding effect. According to the test result of the sample 6, it is inferred that the content of less than 9.09 parts by weight of the ferroferric oxide particles in the film with the nanowire metal wire should not improve the electromagnetic wave shielding effect.

However, the experiments of the present disclosure have found that the incorporation of a low content of ferroferric oxide nanoparticles in a film having a nanowire can impart an unexpected result of an unexpected electromagnetic wave shielding efficiency.

Experimental example 2

The composition of Table 2 (samples 7 to 9) was mixed with 1.22 parts by weight of nano silver wire and mixed with 0 to 1.24 parts by weight of ferroferric oxide particles, respectively, based on 100 parts by weight of the composition. The length-to-diameter ratio of the rice-silver wire is 80, and the particle size of the ferro-oxide-semiconductor particles is 100 nm. Samples 7 to 9 after the completion of the mixing were respectively made into a film having a thickness of 50 μm to test the electromagnetic wave shielding efficiency value. The composition comprises a polymeric material and the polymeric material comprises a polymethyl methacrylate aqueous solution. The methyl methacrylate content is about 45 to 55 parts by weight, and the water is about 55 to 45 parts by weight, based on 100 parts by weight of the polymer material.

Referring to Figures 2 and 3, the films produced in Samples 7 through 9 have lower electromagnetic shielding efficiency than the results of Samples 1, 4 and 5 in which the content of ferroferric oxide particles and nano silver wires are similar. From the results of the simulation shown in Fig. 11, it can be inferred that the electromagnetic shielding efficiency decreases as the aspect ratio of the nano silver wire decreases, and the samples 7 to 9 may be due to the use of a relatively low diameter nano silver wire. , making its electromagnetic shielding less efficient.

For example, the film produced in sample 4 has an electromagnetic shielding efficiency between 38 and 58 dB at frequencies between 2 and 16 GHz. In contrast, the electromagnetic shielding efficiency of sample 8 in the same frequency range is acceptable. Between 20~27dB.

Except for the influence of the aspect ratio of the nano silver wire, similar to the foregoing experiment, the film made from the samples 7 to 9 has a higher electromagnetic shielding efficiency as the content of the ferroferric oxide particles is higher.

Furthermore, the electromagnetic shielding efficiency of the film prepared in sample 4 between 2 and 16 GHz is between 38 and 58 dB. In comparison, it can be seen from Fig. 3 that even if the content of the ferroferric oxide particles is increased to 1.2 parts by weight (sample 9), the electromagnetic shielding efficiency of the film is still less than 35 dB. From this, it can be seen that the effect of adjusting the aspect ratio of the nanowires in the film on the electromagnetic shielding efficiency of the film is greater than that of the nanoparticles in the film. In general, the aspect ratio of the nano silver wire can be 10 or more, 80 or more, or 100 to 300.

Experimental example 3

The composition of Table 3 (samples 10 to 13) comprises 1.14 parts by weight of nano silver wire and respectively containing lanthanum tetraoxide nanoparticles in an amount of 0 to 1.99 parts by weight, based on 100 parts by weight of the composition. The nano silver wire has a length to diameter ratio of 250, and the ferroferric oxide nanoparticle has a particle size of 100 nm. Samples 10 to 13 after the completion of the mixing were each formed into a film having a thickness of 50 μm to test the electromagnetic wave shielding efficiency value. The composition comprises a polymeric material and the polymeric material comprises a polymethyl methacrylate aqueous solution. The methyl methacrylate content is about 45 to 55 parts by weight, and the water is about 55 to 45 parts by weight, based on 100 parts by weight of the polymer material.

Referring to FIG. 2 and FIG. 4, compared with the experimental results of the film having the similar content of the ferroferric oxide nanoparticle in FIG. 2, since the sample 10 to the sample 13 have a lower content of the nano silver wire, Films made from Samples 10 through 13 have lower electromagnetic wave shielding efficiency values. For example, comparing the results of samples 4 and 5 with the results of sample 12, the films produced in samples 4 and 5 have electromagnetic shielding efficiencies between 36 and 58 dB at frequencies between 7 and 16 GHz, while sample 12 is in the same frequency range. The electromagnetic shielding efficiency is in the range of 22 to 27 dB lower.

In addition, it can be seen from the experimental results of Experimental Example 3 that the film can be greatly improved by adding 1.33 parts by weight of the ferroferric oxide particles after adding the film to the film without the addition of the ferroferric oxide particles. Electromagnetic shielding efficiency. Similarly, when too much, such as 1.99 parts by weight of the ferroferric oxide particles of the sample 13, is added, the electromagnetic shielding efficiency is lowered.

From the above results, it can be seen from the experimental results of the sample 4 and the sample 5 in FIG. 2 and the sample 11, the sample 12 and the sample 13 in FIG. 4, when the weight of the wire in the film material is 3%. In the following, when more than 2 parts by weight of particles are added, there is little influence on the improvement of the electromagnetic shielding rate. Therefore, when the particle size of the ferroferric oxide nanoparticle is 80 to 120 nm, the aspect ratio of the nano silver wire is 200 to 300, and the wire material in the film material is 1.0 to 1.3 parts by weight, the triiron telecommunications The content of the rice particles may be 0.1 to 3 parts by weight, 0.2 to 2 parts by weight or 1 to 2 parts by weight.

Experimental example 4

The composition of Table 4 (samples 14 to 17) contained 3 parts by weight of nano silver wire and contained ferrotitanium tetraoxide particles in an amount of 0 to 1.79 parts by weight, respectively, based on 100 parts by weight of the composition. The nano silver wire has an aspect ratio of 250, and the ferroferric oxide nanoparticle has a particle size of 0.5 μm. The sample 14 to the sample 17 after the completion of the mixing were respectively formed into a film having a thickness of 50 μm to test the electromagnetic wave shielding efficiency value. The composition comprises a polymeric material and the polymeric material comprises a polymethyl methacrylate aqueous solution. The methyl methacrylate content is about 45 to 55 parts by weight, and the water is about 55 to 45 parts by weight, based on 100 parts by weight of the polymer material.

Referring to FIG. 2 and FIG. 5, compared with the experiment of FIG. 2, since the sample 14 to the sample 17 have a relatively high content of nano silver wire, the film prepared from the sample 14 to the sample 17 can have a lower film. Surface resistivity. However, comparing the experimental results of FIG. 2 and FIG. 5, it can be found that the films prepared from the samples 14 to 17 do not significantly improve the electromagnetic shielding efficiency due to the lower surface resistivity.

For example, comparing sample 5 with sample 17, the film produced by sample 5 has an electromagnetic shielding efficiency between 36 and 53 dB at a frequency of 6 to 16 GHz, and the film produced with sample 17 is in the same frequency range with electromagnetic shielding. The efficiency is about the lower 9~52dB range. As the concentration of the wire increases, the particles increase their particle size at similar concentrations, and the effect on the high frequency appears to be more pronounced.

Further, referring to FIG. 5, the electromagnetic shielding efficiency of the film prepared from the sample 14 to the sample 16 is compared, and in most of the frequency range, the electromagnetic shielding efficiency is improved as the content of the ferroferric oxide particles increases. Compared with the film in which the Fe3O4 nanoparticles are not added, the electromagnetic shielding efficiency is significantly improved after the film is added with 1.2 parts by weight of the ferroferric oxide particles. Similarly, when more ferroferric oxide nanoparticles, such as 1.79 parts by weight of ferrotitanium tetraoxide particles of sample 17, are added, the electromagnetic shielding efficiency is instead reduced. Therefore, when the particle diameter of the ferroferric oxide nanoparticle is 300 to 700 nm, the aspect ratio of the nano silver wire is 200 to 300, and the thickness of the nanowire in the film material is increased to more than 3 parts by weight, the ferroferric oxide The content of the nanoparticles may be 0.1 to 3 parts by weight, 0.2 to 2 parts by weight or 0.3 to 2 parts by weight.

In addition, it can be seen from the comparison of the experiments of FIG. 2 and FIG. 3 that the use of a nanometer wire having a high aspect ratio contributes to an improvement in the electromagnetic shielding efficiency of the film. Moreover, referring to FIG. 10, if the nanowire in the film material is increased to more than 3 parts by weight, the electromagnetic shielding efficiency cannot be significantly improved; instead, if a different size of nano metal is added to the film material or The magnetically permeable particles can change the optical path difference of the electromagnetic wave of the film material in the high frequency band, and can effectively improve the shielding rate.

Experimental example 5

The composition of Table 5 (Sample 18 to Sample 21) contained 10.45 parts by weight of nano silver wire and contained ferrotitanium tetraoxide particles each having a content of 0 to 1.87 parts by weight, based on 100 parts by weight of the composition. The nano silver wire has a length to diameter ratio of 250, and the ferroferric oxide nanoparticle has a particle size of 30 nm. The sample 18 to the sample 21 after the completion of the mixing were respectively formed into a film having a thickness of 50 μm to test the electromagnetic wave shielding efficiency value. The composition comprises a polymeric material and the polymeric material comprises a polymethyl methacrylate aqueous solution. The methyl methacrylate content is about 45 to 55 parts by weight, and the water is about 55 to 45 parts by weight, based on 100 parts by weight of the polymer material.

Referring to FIG. 2 and FIG. 6, compared with the experiment of FIG. 2, the sample 18 to the sample 21 have a higher content of nano silver wire, so the film made from the sample 18 to the sample 21 can have a lower film. Surface resistivity. Comparing the experimental results of FIG. 2 and FIG. 5, it can be found that the films prepared from the samples 18 to 21 do not significantly improve the electromagnetic shielding efficiency due to the lower surface resistivity. By way of example, comparing sample 5 with sample 21, the electromagnetic shielding efficiency of the film made with sample 5 at a frequency between 4 and 16 GHz is between 36 and 48 dB, while the film produced by sample 21 is in the same frequency range, and the electromagnetic wave is Efficiency is around the lower 25 to 37 dB range.

In addition, comparing the electromagnetic shielding efficiency of the film prepared from sample 18 to sample 21, the electromagnetic shielding efficiency is improved as the content of the ferroferric oxide nanoparticle increases, which is compared with the addition of the ferroferric oxide nanoparticle. In the case of a film, a film in which 1.87 parts by weight of triiron tetroxide particles are added generally has a better electromagnetic shielding efficiency. Therefore, when the particle diameter of the ferroferric oxide nanoparticle is 10 to 50 nm, the aspect ratio of the nano silver wire is 200 to 300, and the nanowire of the film material is increased to 10.45 parts by weight, the triiron tetanate The content of the rice particles may be between 0.4 and 2.6 parts by weight, between 0.6 and 2.4 parts by weight or between 1 and 2 parts by weight.

Therefore, it can be seen from FIG. 5 and FIG. 6 that when the addition of the silver wire reaches a certain degree (refer to FIGS. 8 to 10 again), increasing the addition amount of the silver wire has a limited improvement in the electromagnetic shielding efficiency of the film material, but instead By adding nanoparticles at specific concentrations, the masking rate of the film material to the high frequency is expected to increase.

Experimental example 6

The composition of Table 6 (sample 22 to sample 25) contained 1.14 parts by weight of nano silver wire and silver nanoparticles containing content of 0 to 1.99 parts by weight, respectively, based on 100 parts by weight of the composition; 26 contains only 7.65 parts by weight of silver nanoparticles, but does not contain nano silver wires, wherein the nano silver wire has an aspect ratio of 250, and the silver nanoparticles have a particle diameter of 100 nm. The sample 22 to the sample 26 after the completion of the mixing were respectively formed into a film having a thickness of 50 μm to test the electromagnetic wave shielding efficiency value. The composition comprises a polymeric material and the polymeric material comprises a polymethyl methacrylate aqueous solution. The methyl methacrylate content is about 45 to 55 parts by weight, and the water is about 55 to 45 parts by weight, based on 100 parts by weight of the polymer material.

Referring to FIG. 7, compared to the experiment of FIG. 4, the sample 23 to the sample 26 have conductive silver nanoparticles, so that the film prepared from the sample 23 to the sample 26 can have a lower surface resistivity. However, comparing the experimental results of FIG. 4 and FIG. 7, it can be found that the films prepared from the samples 23 to 26 do not have better electromagnetic shielding efficiency due to the lower surface resistivity. For example, comparing sample 12 to sample 24, the electromagnetic shielding efficiency of sample 12 between the indicated bands is between 18 and 29 dB, except for the resonant mode occurring at a frequency of 4.8 GHz. The electromagnetic shielding efficiency of sample 24 is between 19 and 30 dB, with no difference. From the above experimental results, it is understood that there is no significant difference in electromagnetic shielding efficiency between the film in which the silver nanoparticles are added and the film in which the magnetic particles are added.

Therefore, when the silver nanoparticles have a particle diameter of 80 to 120 nm and the nano silver wire has a length to diameter ratio of 200 to 300, the content of the silver nanoparticles may be 0.5 to 2.5 parts by weight or 0.7 to 0.7. 2 parts by weight.

In addition, comparing the electromagnetic shielding efficiency of the film made from sample 22 to sample 25, the electromagnetic shielding efficiency of simply adding the wire in the film is better than that of adding only particles in the film, and the electromagnetic shielding efficiency is the same as that of the silver nanoparticle. The content is improved and improved, and if the magnetic conductive particles are changed to conductive particles, it seems to have a certain electromagnetic wave avoidance rate. Figure 12 is a graph showing the results of the electromagnetic shielding efficiency of the two films, wherein the two films are based on bisphenol A epoxy resin BE188 (source: Changchun Plastics Co., Ltd., Taiwan). preparation. The two film systems are respectively prepared as a two-component compound, wherein the two components comprise a nanowire having an aspect ratio of 80 and a concentration of 2.06 parts by weight, and a particle diameter of 50 nm and a concentration of 0 parts by weight and 0.65, respectively. Parts by weight of nanoparticles. After the experiment, it was found that even the material of the carrier was changed from acrylic resin to bisphenol A type epoxy (BE188) (Source: Changchun Plastics Co., Ltd., Taiwan) After the addition of the nanoparticles to the carrier, the electromagnetic shielding efficiency of the film made therefrom can be improved. Therefore, the addition of a specific proportion of nanoparticles causes an unexpected effect and is not affected by the use of different polymeric materials.

The film made of the composition having a nanowire and a nanoparticle has an excellent electromagnetic wave shielding effect.

Table 7

From the results of Table 7 and Figure 13, it can be seen that the electromagnetic wave shielding material having the nano structure made of the sample 4 is more than the film made by the conventional products (B and C) of the conventional metal circular particles. Good EMI protection. Moreover, in the composition A of the present disclosure, only a low content of the nano material is required to have a higher electromagnetic wave shielding value than a commercially available product having a high content of particles.

Referring to FIG. 14, the present disclosure further discloses an electromagnetic shielding device 10. The electromagnetic shielding device 10 includes a body 11 and a film 12, wherein the body 11 has a surface 13 on which the film 12 is formed to provide electromagnetic wave shielding. The film 12 can comprise a plurality of nanowires and a plurality of nanoparticles. a plurality of nanowires and a plurality of nanoparticles are uniformly dispersed in the film 12 and mixed with each other, wherein the nanowires are between 1 part by weight and 95 parts by weight based on 100 parts by weight of the film 12; The nanoparticles are contained in an amount of from 0.5 part by weight to 60 parts by weight based on 100 parts by weight of the film. The body 11 can be any object that needs to be coated with the film 12 to shield electromagnetic waves. For example, the body 11 can be a wire, a plate, a polymer film or a casing.

Referring to Figure 15, the present disclosure further discloses an antistatic device 20. The antistatic device 20 includes a substrate 21 and a film 22, wherein the substrate 21 has a surface 23 on which the film 22 is formed to provide electromagnetic wave shielding. The film 22 can comprise a plurality of nanowires and a plurality of nanoparticles. The plurality of nanowires and the plurality of nanoparticles are uniformly dispersed in the film 22 and mixed with each other, wherein the nanowires comprise 1 part by weight of the total weight of the film 22, based on 100 parts by weight of the film. 95 parts by weight; the nanoparticles are from 0.5 part by weight to 60 parts by weight based on the total weight of the film 22.

In summary, by adding an appropriate amount of magnetic conductive or metallic nanoparticles to the composition containing the nanowire, the electromagnetic shielding efficiency of the film made of the composition can be improved. According to the results of the foregoing embodiments, the content of the nano metal wire may be from 1 part by weight to 95 parts by weight, from 1 part by weight to 11 parts by weight or from 1 part by weight to 3 parts by weight of the composition. Parts by weight. Further, the content of the magnetic conductive or metallic nanoparticles may be from 0.1 part by weight to 60 parts by weight, from 0.1 part by weight to 10 parts by weight, from 0.5 part by weight to 10 parts by weight, or from 0.5 part by weight to 2 parts by weight. Share.

Further, by adding a large amount of magnetic conductive or metallic nanoparticles to the composition containing the nanowire, the electromagnetic shielding efficiency is not significantly improved. In addition, the addition of the insulating magnetic nanoparticles to the film increases the electromagnetic shielding efficiency of the nanowire or the metal nanoparticle by increasing the conductivity.

FIG. 16 shows a schematic diagram of an electromagnetic shielding structure 30 in accordance with an embodiment of the present disclosure. The electromagnetic shielding structure 30 includes a target 31 and a film 32. The method for preparing the electromagnetic shielding structure 30 comprises the steps of: providing a target 31; forming a film 32 on the target 31 by coating or spraying; and heating the film 32 to a temperature by illumination or an oven, wherein the temperature is between 50 degrees Celsius to 250 degrees Celsius. The composition of film 32 is as listed in Table 8. The composition is configured for coating or spraying. The composition may comprise nano silver wires and polymeric materials. In some embodiments, the composition further comprises nanoparticle. The polymer material may comprise polyurethane and water, wherein the content of the polyurethane is about 45 to 55 parts by weight, and the water is about 55 to 45 weights, based on 100 parts by weight of the polymer material. Share.

Figure 17 is a view showing an electromagnetic wave shielding efficiency value at a frequency of 0 to 1800 MHz, which is a film made of a mixed material of 2.43 parts by weight of silver nanowires and 1.45 parts by weight of ferroferric oxide particles in an embodiment of the present invention. Measurement chart. Figure 18 is a view showing an electromagnetic wave shielding efficiency value at a frequency of 1 to 18 GHz in a film made of a mixed material of 2.43 parts by weight of silver nanowires and 1.45 parts by weight of ferroferric oxide particles in an embodiment of the present invention. Measurement chart. The sample 27 was coated on a target and then heated at 80 degrees Celsius for 5 minutes to form a film having a thickness of 50 μm. Thereafter, the electromagnetic wave shielding efficiency value of the film was measured. From the measurement results of Figs. 17 and 18, it can be seen that after the film is heated at 80 degrees Celsius for 5 minutes, the electromagnetic wave shielding efficiency is significantly improved at a frequency between 1 and 1800 MHz; and in the high frequency range, it is averaged. The electromagnetic wave shielding efficiency value can be higher than 40 dB.

Fig. 19 is a graph showing the relationship between the electromagnetic wave shielding efficiency value and the heating time of a film made of a mixed material of 2.43 parts by weight of silver nanowires and 1.45 parts by weight of triiron tetroxide particles. The sample 27 was coated on a target and heated at 80 ° C for 5 minutes to produce a film having a thickness of 30 μm. The film is then baked at 150 degrees Celsius and heated for different heating times. Then, the electromagnetic wave shielding efficiency values of the films baked at different heating times were measured, and the results shown in Fig. 19 were obtained. As can be seen from the results shown in Fig. 19, when the film is heated for more than 1 hour, the electromagnetic wave shielding efficiency value can be increased by 10 dB or more. If it is baked at 150 degrees Celsius for 72 hours, the electromagnetic wave shielding efficiency value can reach more than 40dB.

Fig. 20 is a graph showing the relationship between the electromagnetic wave shielding efficiency value and the heating temperature of a film made of a mixed material of 2.43 parts by weight of silver nanowires and 1.45 parts by weight of ferroferric oxide particles. The sample 27 was coated on a target and heated at 80 ° C for 5 minutes to produce a film having a thickness of 20 μm. The film was then heated at different heating temperatures for a fixed period of 1 hour. Then, the electromagnetic wave shielding efficiency values of the films heated at different temperatures were measured, and the results shown in Fig. 20 were obtained. As can be seen from the results shown in Fig. 20, the electromagnetic wave shielding efficiency value of the film increases as the heating temperature increases. Therefore, the film can be adjusted to the heating temperature to obtain the desired electromagnetic wave shielding efficiency value. Further, the film heated at the temperature shown in Fig. 20 can be tested by pencil hardness B and adhesion degree 4B.

Figure 21 is a view showing an electromagnetic wave shielding efficiency value at a frequency of 0 to 1800 MHz in a film made of a mixed material of 3.49 parts by weight of silver nanowires and 2.18 parts by weight of ferroferric oxide particles in an embodiment of the present invention. Measurement chart. Figure 22 is a view showing an electromagnetic wave shielding efficiency value at a frequency of 1 to 18 GHz in a film made of a mixed material of 3.49 parts by weight of silver nanowires and 2.18 parts by weight of ferroferric oxide particles in an embodiment of the present invention. Measurement chart. The sample 28 was coated on a target and then heated at 80 degrees Celsius for 5 minutes to form a film having a thickness of 80 μm. Thereafter, the electromagnetic wave shielding efficiency value of the film was measured. From the measurement results of Figs. 21 and 22, it can be known that after the film is heated at 80 degrees Celsius for 5 minutes, the electromagnetic wave shielding efficiency value can be higher than 40 dB. Furthermore, since the ferroferric oxide particles and the silver nanowire are mixed, the film can generate multiple scattering and absorption effects, so that better electromagnetic wave shielding efficiency can be obtained.

Figure 23 is a view showing a film made of a mixed material of 2.1 parts by weight of silver nanowires and 0.55 parts by weight of triiron tetroxide particles in an embodiment of the present invention, after different heating times and heating temperatures, at a frequency Measure the electromagnetic wave shielding efficiency value between 0 and 1800 MHz. The sample 29 was coated on a target and then heated at 80 degrees Celsius for 5 minutes to form a film having a thickness of 70 μm. Measuring the electromagnetic wave shielding efficiency of the film can be as shown in Fig. 23. Further, the film was placed in an oven and baked again at 150 ° C for 24 hours, and then the electromagnetic wave shielding efficiency was tested, and the results as shown in Fig. 23 were obtained. Comparing the results shown in Fig. 23, it can be seen that if the film is baked for another 24 hours and 150 degrees Celsius, the electromagnetic wave shielding efficiency value can be increased by 10 dB.

Figure 24 is a view showing a film made of a mixed material of 1.09 parts by weight of silver nanoparticles and 3.69 parts by weight of ferroferric oxide particles in an embodiment of the present invention, which has a frequency of 100 to 1800 MHz after different heating times. A measure of the electromagnetic wave shielding efficiency value between. The sample 30 was coated on a target and then heated at 80 degrees Celsius for 5 minutes to form a film having a thickness of 30 μm. Thereafter, the film was heated at different temperatures for 1 hour. Then, the electromagnetic wave shielding efficiency of the film was measured, and the results are shown in Fig. 24. It can be seen from the results shown in Fig. 24 that by heating above 80 degrees Celsius, the electromagnetic wave shielding efficiency value of the film can be increased by more than 40 dB.

Referring to FIG. 16, the electromagnetic shielding structure 30 may include a target 31, a film 32, and an adhesive layer 33. The film 32 is disposed on the target 31, and the adhesive layer 33 is disposed on the film 32. In one embodiment, the adhesive layer 33 comprises a pressure sensitive adhesive. In addition, in another embodiment, the electromagnetic shielding structure 30 may further include at least one second film (not shown), wherein the second film overlaps the film 32 and may be located between the adhesive layer 33 and the film 32. And the film 32 and the second film may have nano particles and a nano metal wire, respectively.

Figure 25 is a graph showing the relationship between electromagnetic strength and frequency obtained by measuring a hard disk having no anti-electromagnetic interference film. Fig. 26 is a graph showing the relationship between the electromagnetic field strength and the frequency obtained by measuring a hard disk having an electromagnetic interference resistant film (sample 31). The result of Figure 25 is that a hard disk is produced according to the EU Electromagnetic Compatibility Directive (EU-EMC Directive (2004/108/EC) EN 55022 class B), which is at frequencies 377, 486 and 593 MHz (number 4, 5, 6 marked) exceeds the standard. The sample 31 was coated on the hard disk to form a film having a thickness of less than 50 μm. After the film was dried, the hard disk was found to meet the EU electromagnetic compatibility guidelines in the frequency range of 30 MHz to 1.8 GHz. Therefore, the film produced by the sample 31 of the present disclosure can reduce the generation of electromagnetic interference. The polymer materials used in the samples 31-32 contained an aqueous polyurethane solution (containing 45 to 55 parts by weight of polyurethane and 55 to 45 parts by weight of water).

Figure 27 is a graph showing the relationship between the intensity of the electromagnetic field and the frequency obtained by measuring the film in a horizontal direction without a film having an anti-electromagnetic interference film. Figure 29 is a graph showing the relationship between the intensity of the electromagnetic field and the frequency obtained by measuring the film in a vertical direction without a film having an anti-electromagnetic interference film. Fig. 28 is a view showing the relationship between the intensity of the electromagnetic field and the frequency obtained by measuring the recording and reproducing machine of the film having the electromagnetic interference resistance (sample 32) in the horizontal direction. Figure 30 is a graph showing the relationship between the intensity of the electromagnetic field and the frequency obtained by measuring the film in a vertical direction with a film with anti-electromagnetic interference (sample 32). According to the EU Electromagnetic Compatibility Guidelines, the electromagnetic wave interference in the horizontal and vertical directions of the video recorders without anti-electromagnetic interference film can be found to be inconsistent with the standard at 15 frequencies and 17 frequencies. However, the film 32 was formed on the recording and reproducing machine with an electromagnetic interference resistant film (thickness less than 50 micrometers). After the film was dried, the video recorder was found to comply with the EU electromagnetic compatibility guidelines. Therefore, the film produced by the present disclosure 32 has a large bandwidth electromagnetic shielding effect.

The shielding rate of conventional electromagnetic waves is usually positively correlated with the conductivity. However, from the experimental results of the samples 31 and 32, it is known that when the conductive metal material is added to a certain extent, the influence on the shielding rate is limited.

Samples 31 and 32 include a polymer material, which may include a polyurethane and water, wherein the content of the polyurethane is about 45 to 55 parts by weight based on 100 parts by weight of the polymer material. The water is about 55 to 45 parts by weight.

In summary, the disclosure further discloses that the anti-electromagnetic interference film with nano material is heat-treated, and the electromagnetic wave shielding efficiency value of the film can be effectively improved. Therefore, the thickness of the film to be used can be reduced without reducing the electromagnetic shielding effect.

The technical content and technical features of the present disclosure have been disclosed as above, and those skilled in the art can still make various substitutions and modifications without departing from the spirit and scope of the disclosure. Therefore, the scope of the present disclosure is not to be construed as being limited by the scope of

10. . . Electromagnetic shielding device

20. . . Antistatic device

30. . . Electromagnetic shielding structure

11. . . Ontology

12. . . film

13. . . surface

twenty one. . . Substrate

twenty two. . . film

twenty three. . . surface

31. . . Target

32. . . film

33. . . Adhesive layer

1 and FIG. 2 are schematic diagrams showing the relationship between the electromagnetic wave shielding efficiency value and the frequency of a film having different content of ferroferric oxide nanoparticles according to an embodiment of the present disclosure;

3 is a schematic diagram showing the relationship between electromagnetic wave shielding efficiency values and frequency of a plurality of films according to an embodiment of the present invention, wherein the films comprise nano silver wires having an aspect ratio of 80 and respectively containing different contents of triiron tetroxide. particle;

4 is a schematic diagram showing the relationship between electromagnetic wave shielding efficiency values and frequency of a plurality of films according to an embodiment of the present invention, wherein the films comprise 1.14 parts by weight of nano silver wire and respectively contain different contents of triiron tetanate. Made of a composition of particles;

5 and FIG. 6 are schematic diagrams showing the relationship between electromagnetic wave shielding efficiency values and frequencies of a film having a high nano silver content according to an embodiment of the present disclosure;

7 is a schematic view showing the relationship between electromagnetic wave shielding efficiency values and frequency of a nano silver wire and a silver nanoparticle film according to an embodiment of the present disclosure;

Figure 8 is a graph showing the relationship between surface resistivity and nanowire concentration in an embodiment of the present disclosure;

Figure 9 is a graph showing the relationship between the electromagnetic wave shielding efficiency value of the material and the surface resistivity under the condition that a nano silver wire having a length to diameter ratio of 200 is used;

10 is a schematic diagram showing the relationship between electromagnetic wave shielding efficiency values and frequency of a plurality of films according to an embodiment, wherein the films are made of a composition comprising 1.14, 3, and 10.45 parts by weight of nano silver wire;

Figure 11 is a graph showing the relationship between the electromagnetic wave shielding efficiency value and the volume percentage of materials having different aspect ratios;

Figure 12 is a graph showing the relationship between electromagnetic wave shielding efficiency values and frequency using a composition in which an epoxy resin is used as a carrier and mixed with nanoparticles of different concentrations;

Figure 13 is a graph showing the relationship between the electromagnetic wave shielding efficiency value and the frequency of the composition of the present disclosure and a conventional product;

Figure 14 is a schematic view showing an electromagnetic shielding device according to an embodiment of the present disclosure;

Figure 15 is a schematic view showing an antistatic device according to an embodiment of the present disclosure;

Figure 16 is a schematic view showing an electromagnetic shielding structure according to an embodiment of the present disclosure;

Figure 17 is a view showing the amount of electromagnetic wave shielding efficiency at a frequency of 0 to 1800 MHz in a film made of a mixed material of 2.43 parts by weight of a silver wire and 1.45 parts by weight of a ferroferric oxide particle in an embodiment of the present invention. Mapping

Fig. 18 is a view showing the amount of electromagnetic wave shielding efficiency at a frequency of 1 to 18 GHz in a film made of a mixed material of 2.43 parts by weight of silver nene and 1.45 parts by weight of ferroferric oxide particles in an embodiment of the present invention. Mapping

Figure 19 is a graph showing the relationship between the electromagnetic shielding efficiency value and the heating time of a film made of a mixed material of 2.43 parts by weight of a silver nene line and 1.45 parts by weight of a ferroferric oxide particle;

Figure 20 is a graph showing the relationship between the electromagnetic shielding efficiency value and the heating temperature of a film made of a mixed material of 2.43 parts by weight of a silver nene line and 1.45 parts by weight of a ferroferric oxide particle;

Figure 21 is a view showing an electromagnetic wave shielding efficiency value at a frequency of 0 to 1800 MHz in a film made of a mixed material of 3.49 parts by weight of silver nanoparticles and 2.18 parts by weight of ferroferric oxide particles in an embodiment of the present invention. Measurement map

Figure 22 is a view showing an electromagnetic wave shielding efficiency value at a frequency of 1 to 18 GHz in a film made of a mixed material of 3.49 parts by weight of silver nanoparticles and 2.18 parts by weight of ferroferric oxide particles in an embodiment of the present invention. Measurement map

Figure 23 is a view showing a film made of a mixed material of 2.1 parts by weight of silver nanowires and 0.55 parts by weight of ferroferric oxide particles in an embodiment of the present invention, after different heating time and heating temperature, at a frequency Measure the electromagnetic wave shielding efficiency value between 0 and 1800 MHz;

Figure 24 is a view showing a film made of a mixed material of 1.09 parts by weight of silver nanoparticles and 3.69 parts by weight of ferroferric oxide particles in an embodiment of the present invention, at a different heating temperature, at a frequency of 100~ a measurement map of electromagnetic wave shielding efficiency values between 1800 MHz;

Figure 25 is a graph showing the relationship between electromagnetic strength and frequency obtained by measuring a hard disk having no anti-electromagnetic interference film;

Figure 26 is a graph showing the relationship between the electromagnetic field strength and the frequency obtained by measuring a hard disk having a film resistant to electromagnetic interference;

Figure 27 is a view showing the relationship between the intensity of the electromagnetic field and the frequency obtained by measuring the film in a horizontal direction without a film having an anti-electromagnetic interference film;

Figure 28 is a graph showing the relationship between the obtained electromagnetic field strength and the frequency of a hard disk having a film resistant to electromagnetic interference, measured in a horizontal direction;

Figure 29 is a view showing the relationship between the intensity of the electromagnetic field and the frequency obtained by measuring the film in a vertical direction without a film having an anti-electromagnetic interference; and

Figure 30 is a graph showing the relationship between the electromagnetic field strength and the frequency of a hard disk having a film resistant to electromagnetic interference measured in a vertical direction.

10. . . Electromagnetic shielding device

11. . . Ontology

12. . . film

13. . . surface

Claims (24)

A composition for electromagnetic shielding, comprising: a carrier; a plurality of nanowires, dispersed in the carrier, wherein the nanowires are between 1 part by weight based on 100 parts by weight of the composition To 11 parts by weight; and a plurality of nanoparticles, dispersed in the carrier, wherein the nanoparticles are between 0.13 parts by weight and 9.09 parts by weight based on 100 parts by weight of the composition. The composition of claim 1, wherein the nanoparticles are metal or metal oxides, and the nanoparticles are between 0.5 parts by weight and 20 parts by weight. The composition of claim 1 wherein the nanoparticles are gold, silver, copper, indium, palladium, aluminum, iron, cobalt, nickel or a mixture, alloy or oxide of the foregoing. The composition of claim 2, wherein the nanoparticles are nano silver particles, nano-ferric oxide particles or a mixture of the foregoing particles. The composition of claim 1 wherein the nanowires have an aspect ratio greater than 10. The composition of claim 1 wherein the nanoparticles have a particle size of less than 1000 nm. The composition of claim 1 wherein the ratio of the nanowires to the nanoparticles is greater than 0.1. The composition according to claim 1, wherein the nanowire is gold, silver, copper, indium, palladium, aluminum, iron, cobalt, nickel or a mixture of the foregoing metals, Alloy or oxide. The composition according to claim 1, wherein the nano metal wire is a gold-coated silver nanowire, a silver-coated gold nanowire, a gold-coated copper nanowire, a copper-coated gold nanowire, and a silver. A copper-coated nanowire, a copper-coated silver nanowire, or a combination thereof. The composition according to claim 1, wherein the nanoparticle is a gold-coated silver nanoparticle, a silver-coated gold nanoparticle, a gold-coated copper nanoparticle, a copper-coated gold nanoparticle, and a silver package. Copper-coated nanoparticle, copper-coated silver nanoparticle or a combination thereof. A composition for electromagnetic shielding, comprising: a carrier; a plurality of nanowires, dispersed in the carrier, the nanometer metal wires having an aspect ratio greater than 10, the nanowires being gold and silver a mixture, alloy or oxide of copper, indium, palladium, aluminum, iron, cobalt, nickel or the foregoing metals, wherein the nanowires are between 1 part by weight and 11 parts by weight based on 100 parts by weight of the composition. And a plurality of nano particles dispersed in the carrier, the nano particles being less than 1000 nm, the nanoparticles being gold, silver, copper, indium, palladium, aluminum, iron, cobalt, nickel or the foregoing metal a mixture, alloy or oxide, wherein the nanoparticles are between 0.13 parts by weight and 9.09 parts by weight. The composition of claim 11, wherein the nanoparticles are between 0.5 parts by weight and 9.09 parts by weight, and the composition thus used for electromagnetic shielding has an electromagnetic wave shielding efficiency value greater than 10 dB. The composition of claim 11 wherein the nanowires are The aspect ratio is 20 to 500; the nanoparticles have a particle size of 10 to 1000 nm; and the nanowires are between 1 and 3 parts by weight, wherein the nanoparticles comprise the composition. The total weight is from 0.5 part by weight to 2 parts by weight, and the composition thus used for electromagnetic shielding has an electromagnetic wave shielding efficiency value of more than 10 dB. An electromagnetic shielding device comprising: a body having a surface; and a film formed on the surface of the body to shield electromagnetic waves, the film comprising: a plurality of nanowires, dispersed in the film, wherein The film is 100 parts by weight, the nano metal wires are between 1 part by weight and 11 parts by weight; and a plurality of nano particles are dispersed in the film, wherein the nanometers are 100 parts by weight of the film. The particles are between 0.13 parts by weight and 9.09 parts by weight. The electromagnetic shielding device according to claim 14, wherein the nano particles are conductive particles, magnetic conductive particles, insulating magnetic conductive particles or a combination thereof, and the nano particles are between 0.5 parts by weight and 2 parts by weight. An antistatic device comprising: a substrate; and a film formed on the substrate, the film comprising: a plurality of nanowires, dispersed in the film, wherein the film is 100 parts by weight of the film a metal wire of between 1 part by weight and 11 parts by weight; A plurality of nanoparticles are dispersed in the film, wherein the nanoparticles are between 0.13 parts by weight and 9.09 parts by weight based on 100 parts by weight of the film. The antistatic device according to claim 16, wherein the nanoparticles are conductive particles, magnetically permeable particles, insulated magnetically permeable particles or a combination thereof, and the nanoparticles are between 0.5 parts by weight and 2 parts by weight. A method for preparing an electromagnetic shielding structure, comprising the steps of: providing a target; providing a mixed material comprising a plurality of nanowires and a plurality of nano particles, wherein the long diameter of the nanowires a ratio greater than 50; using the mixed material to form a first film on one surface of the target; and heating the first film to a temperature between 50 degrees Celsius and 250 degrees Celsius; wherein the first film The nano metal wires are from 1 part by weight to 11 parts by weight, and the nanoparticles are from 0.13 parts by weight to 9.09 parts by weight, based on 100 parts by weight. The preparation method according to claim 18, wherein the material of the nano metal wires is gold, silver, copper, indium, palladium, aluminum, iron, cobalt, nickel or a mixture, alloy or oxide of the foregoing metals. The preparation method according to claim 18, wherein the mixed material comprises a plurality of nano particles, wherein the nano particles are silver particles, triiron tetroxide particles or a mixture thereof. The preparation method according to claim 20, wherein the nanoparticles comprise 0.1 to 5 parts by weight based on the total weight of the first film. The preparation method according to claim 20, wherein the nanoparticles are less than 1000 nm. The preparation method of claim 18, further comprising a second film comprising a plurality of nano particles, wherein the first film is disposed on the second film. The preparation method according to claim 18, wherein the step of heating the first film to a temperature between 50 degrees Celsius and 250 degrees Celsius enables the first film to increase the shielding ratio between frequencies of 4 G to 16 G.