KR20090010595A - Electromagnetic absorber sheet enhanced thermal conductivity - Google Patents

Abstract

An electromagnetic absorber capable of improving thermal conductivity with Ni-Zn ferrite is provided to reduce bad effect reached on human body by emitting heat generated in electronic devices. An electromagnetic absorber(10) comprises a polymer matrix(120) and a filler(110). The polymer matrix comprises a resin compound, a catalyst, and a viscosity modifier. The resin compound comprises a room temperature hardening 2 liquid type silicone gel resin and a thermosetting 1 liquid type silicon gluing agent resin. The 2 liquid type silicone gel resin is vinylpolymethylsiloxane. The catalyst accelerates hardening of the resin compound. The viscosity modifier controls viscosity of the resin compound. The filler is mixed in the polymer matrix.

Description

Electromagnetic absorber sheet enhanced thermal conductivity

The present invention relates to an electromagnetic wave absorber which has improved thermal conductivity by applying Ni-Zn ferrite as a filler. It relates to an electromagnetic wave absorber in the form of a gel having an absorption function and a heat conduction function simultaneously.

Recently, due to the rapid development of the electric and electronic industry and information and communication technology, the integration of circuits mounted on them is increasing due to the trend of portability and slimming of products and devices.

In addition, electronic components mounted in the integrated circuit operate based on electrical energy, which inevitably generates thermal energy.

In particular, as a package such as a CPU is highly integrated, power consumption and calorific value increase, and as the precision becomes more sensitive, it becomes more sensitive to small impacts and interferences, so that heat problems in electronic products are highlighted.

In order to solve such a problem of deterioration of performance, a heat sink for transferring heat such as an IC package made of a metal plate and dissipating it to the outside is used.

The heat sink is installed on an electronic component or an electronic component module which is a heat generating source, and has a wide surface area and a good ventilation structure, thereby quickly dissipating heat generated.

When contacting such a heat sink and an electronic component, a gap may be formed due to the flatness of the surface to be contacted, so that effective thermal conductivity may not be achieved. Therefore, in order to increase thermal conductivity, grease, silicon rubber sheet, etc. having good thermal conductivity may be used. The method of fitting and mounting is conventionally performed.

Conventional thermally conductive greases are not affected by surface irregularities of electronic parts, heat sinks, etc., and can cope with or adhere to their adherend surfaces and have low interfacial thermal resistance. There was a defect such as separation.

In addition, the thermally conductive silicone rubber sheet has the advantage that it can be easily mounted, but in terms of processing in the manufacturing process, the content of the thermally conductive filler is limited, and the adhesion to the surface to be adhered is insufficient, so that the interface thermal resistance at the time of mounting is large. There existed a fault which heat dissipation characteristic is not fully exhibited.

As a countermeasure against this problem, it is possible to reduce the contact thermal resistance, but it is impossible to avoid the problem of electromagnetic interference inside the electronic device.

Currently, electromagnetic waves generated by the above-mentioned increase in the internal circuit density of electronic devices leak through the junctions and connections of the electronic devices, act as noise, and disturb the other circuits and components, causing problems such as malfunction of the device. .

In addition, when the human body is exposed to the electromagnetic waves generated from such electronic devices for a long time, it has been reported that the temperature of biological tissue cells is increased by thermal action, thereby weakening immune function and lowering fertility, and thus adversely affecting the human body.

Therefore, in order to shield the electromagnetic waves from electromagnetic waves, a conductive material was used to cover the electronic components or to contact them with a gasket.

However, these are conductive materials, which may cause electrical short when contacted with the electronic components, so that they are installed at a constant distance from the electronic components, thereby causing problems in heat dissipation.

On the other hand, in recent years, with the high integration and high functionality of electronic products, there is an increased risk of a hot topic due to the high temperature generated in electric and electronic components. In addition, it is mandatory to pass the strict standard, and the flame retardancy of the used product is regulated in Korea.

As such, the flame retardancy problem is a matter that must be considered in a situation in which heat generation due to high integration and high speed of circuits becomes more and more serious, and it is a problem that must be solved in the fields of electric and electronic materials and various related parts. In the case of this case, there is a problem that almost no consideration for such flame retardancy.

Therefore, there is an urgent need for the insulation part of the electromagnetic wave absorber, and at the same time, there is a need for an improvement in technology for excellent heat dissipation property that effectively dissipates heat generated inside the electronic device and dissipates it to the outside.

The present invention has been made to improve the above problems, by applying Ni-Zn ferrite as a filler to absorb the electromagnetic waves to reduce the malfunction of the machine and adverse effects on the human body and at the same time generated inside the electronic device with improved thermal conductivity It is an object of the present invention to provide an electromagnetic wave absorber having a property of effectively dissipating heat to the outside.

In addition, it is an object of the present invention to provide an electromagnetic wave absorber that has a self-adhesive force as a gel-shaped sheet and is easy to apply to an apparatus and does not have a separate tape, thereby improving characteristics such as inherent electromagnetic wave absorption.

The electromagnetic wave absorber according to the present invention for solving the above technical problem is a resin mixture comprising a room temperature-curable two-component silicone gel resin and a thermosetting one-component silicone pressure-sensitive adhesive resin, a catalyst for promoting the curing of the resin mixture and the viscosity of the resin mixture Polymer matrix having a viscosity modifier to control; And a filler mixed in the polymer matrix.

The two-component silicone gel resin contained in the resin mixture is characterized in that the vinyl polymethyl siloxane (Vinylpolymethylsiloxane).

The vinyl polymethylsiloxane (Vinylpolymethylsiloxane) is a two-component silicone gel resin in a total of 100 parts by weight of A (topic), B (curing agent) of 45 parts by weight to 55 parts by weight: 55 parts by weight to 45 parts by weight of It is characterized by mixing at a ratio.

The resin mixture is based on a total of 100 parts by weight of the resin mixture, the two-component silicone material and the thermosetting resin are mixed in a ratio of 90 parts by weight to 97 parts by weight: 10 parts by weight to 3 parts by weight. It is done.

The catalyst is a composition containing a platinum containing compound and carbon black, a composition containing a platinum containing compound and fumed titanium dioxide, a composition containing a platinum containing compound and an azo compound, a composition containing a platinum compound and iron oxide, a platinum containing compound and It is any one selected from the composition which mix | blended the triazole type compound, the composition which mix | blended the platinum containing compound, the nitrogen-containing organic group, and the organosilicon compound containing an unsaturated group.

The catalyst is characterized in that the content of the platinum compound to promote the curing of the resin mixture is mixed in 0.1 to 2 phr (per hundred resin) in a total of 100 parts by weight of the resin mixture.

The viscosity modifier is characterized in that using a silicone oil.

The viscosity modifier is characterized in that dimethyl cyclopolysiloxane (dimethyl cyclo- poly siloxane).

The filler is characterized in that the Ni-Zn ferrite mixed with 6wt% to 8wt% of nickel (Ni), 10wt% to 15wt% of zinc (Zn), and Fe ₂ O ₃ or Fe ₂ O ₄ in the remaining amount.

The Ni-Zn ferrite is further characterized by adding CuO.

The filler is characterized in that formed in the powder form of 1㎛ to 10㎛ size.

The backlight assembly according to the present invention for solving the above technical problem is characterized in that it comprises the electromagnetic wave absorber.

The liquid crystal display device according to the present invention for solving the above technical problem is characterized in that it comprises the electromagnetic wave absorber.

The electromagnetic wave absorber according to the present invention has an effect of improving thermal conductivity while absorbing electromagnetic waves by using Ni-Zn ferrite, which is a soft magnetic material, as a filler.

In addition, the electromagnetic wave absorber according to the present invention absorbs electromagnetic waves of the electronic device and simultaneously dissipates heat generated inside the electronic device to the outside, thereby reducing the malfunction of the machine and adverse effects on the human body.

In addition, the electromagnetic wave absorber according to the present invention has a self-adhesive force as a sheet in the form of a gel is easy to apply to the apparatus, there is an effect that can maintain the unique characteristics without the attachment of a separate tape.

In addition, according to the present invention, by adding a platinum-based compound to the binder resin, it is possible to impart flame retardancy to the electromagnetic wave absorber, thereby effectively coping with the flame retardancy problem currently required for a wide range of electric and electronic materials and components.

Specific details of other embodiments are included in the detailed description and the accompanying drawings.

Advantages and features of the present invention, and methods for achieving them will be apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings.

However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various different forms, only the embodiments are to make the disclosure of the present invention complete, and the general knowledge in the technical field to which the present invention belongs. It is provided to fully convey the scope of the invention to those skilled in the art, and the present invention is defined only by the scope of the claims. Like reference numerals refer to like elements throughout.

1 is a view showing an electromagnetic wave absorber according to the present invention.

Referring to FIG. 1, the electromagnetic wave absorber 10 according to the present invention includes a polymer matrix 120 and a filler 110 mixed / dispersed in the polymer matrix 120.

The filler 110 may be formed in a powder form, mixed / dispersed in the polymer matrix 120, and formed of a Ni—Zn ferrite series capable of absorbing electromagnetic waves.

The Ni-Zn ferrite has an effect of blocking electromagnetic waves, and may be converted into heat by absorbing electromagnetic waves as a material having improved thermal conductivity. In other words, it is a material capable of absorbing harmful electromagnetic waves and releasing the absorbed electromagnetic waves as heat.

The Ni-Zn ferrite includes NiO and ZnO, and Fe ₂ O ₃ or Fe ₂ O ₄ may be mixed with the remaining amount.

The Ni-Zn ferrite may further add CuO.

The size of the Ni-Zn ferrite powder is preferably 1 to 10 µm, and preferably a powder having an average particle size of 5.10 µm and a compressive density of 3.61 g / cm 3.

And the composition of the Ni-Zn ferrite powder is formed of the content of the nickel (Ni) 6 ~ 8%, zinc (Zn) 10 ~ 15%.

The polymer matrix 120 will be described later in detail in the manufacturing process of the electromagnetic wave absorber and will be briefly described.

The polymer matrix 120 may be formed by mixing a resin mixture, a catalyst, and a viscosity modifier.

The resin mixture may allow the electromagnetic wave absorber 10 to have a predetermined shape, and may be formed by mixing a two-component silicone gel resin and a thermosetting one-component adhesive resin.

The thermosetting one-component pressure-sensitive adhesive resin may be a polymer and a low molecular material including epoxy resin, phenolic resin, furan resin, ester vinyl, and vinyl ester.

On the other hand, the resin mixture, the two-component silicone gel resin and the thermosetting one-component pressure-sensitive adhesive resin can be used by mixing a mixing ratio of 90 to 97%: 10 to 3%.

The catalyst may use platinum (Pt), it may be used as an additive that can promote the curing of the resin mixture.

The viscosity modifier may be used, such as silicone oil. The viscosity modifier may be used dimethyl cyclopolysiloxane (dimethyl cyclo- poly siloxane).

As such, the electromagnetic wave absorber 10 according to the present invention has a predetermined shape by the polymer matrix 120 and is formed of Ni-Zn ferrite mixed / dispersed in the polymer matrix 120. Absorption of electromagnetic waves can block the malfunction of electronic products that generate electromagnetic waves and electromagnetic waves harmful to humans.

In addition, as the resin mixture, a silicone resin mixture having excellent heat resistance may be preferably used, and a small amount of a platinum-based compound is preferably used for the purpose of promoting hardening and improving flame retardancy.

Further, in order to further increase the flame retardancy in adding the platinum compound as the catalyst, a composition containing a platinum-containing compound and carbon black, a composition containing a platinum-containing compound and a fumed titanium dioxide, and a composition containing a platinum-containing compound and an azo compound Can be optionally added one of a composition containing a platinum compound and iron oxide, a composition containing a platinum-containing compound and a triazole compound, a composition containing a platinum-containing compound and an organosilicon compound containing a nitrogen-containing organic group and an unsaturated group. Can be.

The content of the platinum compound is preferably added in the range of 0.1 ~ 2 phr (per hundred resin) relative to the resin mixture content.

The electromagnetic wave absorber according to the present invention was measured at a test voltage of 100 V using SRM-110 (manufactured by Wolfgang Warmbier, Germany), a surface resistance measuring instrument that complies with EN (European Standard) 61340-5-1. ¹² Ω or more.

Therefore, the electromagnetic wave absorber according to the present invention with the surface resistance as described above can minimize the defect of the electronic products generated by the electrical short.

In addition, the electromagnetic wave absorber according to the present invention exhibited an average breakdown voltage (DBV, Dielectric Breakdown Voltage) measured by preparing 20 specimens of 100 mm × 100 mm and 1.0 mm thickness in accordance with ASTM D149.

As a result of the measurement of the dielectric breakdown voltage, the electromagnetic wave absorber according to the present invention was excellent in terms of insulation required when applied to an electric and electronic component due to the extremely high dielectric breakdown voltage value.

2 is a graph showing the electromagnetic wave absorption characteristics of the electromagnetic wave absorber according to the present invention. Here, the electromagnetic wave absorber according to the present invention will be described with reference to FIG.

Prepare a specimen of the electromagnetic wave absorber according to the present invention in the coaxial form of the outer diameter of 7mm, inner diameter of 3mm and measure the reflection loss (S11, reflection loss) according to KS C0305 by using a network analyzer to determine the value as the electromagnetic wave absorption rate. And measured in dB. And the electromagnetic wave absorptivity was measured according to the thickness of the electromagnetic wave absorber.

2, it can be seen that the electromagnetic wave absorber 10 according to the present invention absorbs the provided high frequency.

It can be seen that when the thickness of the electromagnetic wave absorber 10 is 1.25mm, it absorbs 6 to 8dB for 5 to 6GHz provided, and when the thickness of the electromagnetic wave absorber is 1.5mm, 3.5 to 4.5GHz provided It can be seen that it absorbs 5-6 dB in the frequency band.

Figure 3 is a graph of the result of measuring the thermal conductivity according to the thickness of the electromagnetic wave absorber according to the present invention.

The device was constructed based on ASTM D5470, and the specimens were prepared and measured in squares of 50mm × 50mm. The thermal conductivity was calculated based on the Fourier equation and expressed in units of W / mK.

Referring to Figure 3, the electromagnetic wave absorber 10 according to the present invention was measured for each thermal conductivity in the thickness range of 0.6 to 1.6mm.

Here, the thermal conductivity of the electromagnetic wave absorber was measured 1.3 to 1.7W / mK.

4 is a flowchart illustrating a method of manufacturing an electromagnetic wave absorber according to the present invention.

Here, the electromagnetic wave absorber has a gel type sheet shape as an example. And for the easy description of the electromagnetic wave absorber of the present invention will be described with reference to FIG.

As shown in FIG. 4, a polymer matrix 120 is prepared to enable the electromagnetic wave absorber 10 to have a predetermined shape. Here, a resin mixture is formed to allow the polymer matrix 120 to have a predetermined shape. (S100)

The resin mixture may be formed by mixing a two-part silicone gel resin and a thermosetting one-part adhesive resin.

The two-component silicone gel resin may be formed by mixing vinyl polymethyl siloxanes A and B. Here, the mixing ratio of the vinyl polymethyl siloxanes A and B may be formed by mixing at a ratio of 45 to 55%: 55 to 45%.

The thermosetting one-component pressure-sensitive adhesive resin may be a polymer and a low molecular material including epoxy resin, phenolic resin, furan resin, ester vinyl, and vinyl ester.

On the other hand, the resin mixture, the two-component silicone gel resin and thermosetting one-component pressure-sensitive adhesive resin can be used by mixing the mixing ratio of 90 ~ 97%: 10 ~ 3%.

The process of mixing the viscosity modifier 620 to the resin mixture is carried out. (S200)

The viscosity modifier may reduce the viscosity of the resin mixture including the two-component silicone gel resin.

The viscosity modifier may be used, such as silicone oil. As the viscosity modifier, a polymer material including dimethyl cyclopolysiloxane may be used.

As such, the first mixture may be formed by mixing the viscosity modifier with the resin mixture.

The filler 110 is mixed in the first mixture in which the resin mixture and the viscosity modifier are mixed. (S300)

The filler 110 may be used Ni-Zn ferrite.

Here, the filler 110 may be mixed in two stages in total. In one step, 50 to 70% of the total weight may be mixed with the first mixture, and the remaining 50 to 30% of the filler 110 may be mixed in two stages. Can be.

More number of mixing steps is advantageous in terms of improving dispersion and minimizing mixing heat, but it is preferable to divide the process into two or three times in terms of process.

The step-by-step mixing as described above is to minimize the heat of kneading generated during the mixing of the composition and to uniformly disperse the filler 110 in the first mixture including the resin mixture.

As such, the second mixture may be formed by mixing the filler 110 with the first mixture.

The catalyst is mixed as an additive to the second mixture formed in the previous step. (S400)

The catalyst may promote hardening of the second mixture and improve flame retardancy.

A platinum (Pt) -based compound may be used as the catalyst, and the third mixture may be formed by mixing the catalyst with the second mixture.

The third mixture may be formed in a gel state due to the resin mixture, and a casting process may be performed to form the electromagnetic wave absorber 10 in a predetermined shape.

The third mixture is cast using a casting apparatus or the like so that the third mixture has a predetermined shape. (S500)

Here, it will be described as an embodiment in which the third mixture is formed in a sheet shape.

The third mixture preferably has a predetermined shape for easy application of the electromagnetic wave absorber 10 of the present invention to an actual product.

Therefore, the third mixture is formed to have a predetermined shape to form the electromagnetic wave absorber 10.

In the casting process, predetermined heat energy may be provided to the third mixture. Therefore, the third mixture may be cured due to the room temperature-curable two-component silicone gel resin and the thermosetting one-component silicone adhesive resin included in the third mixture.

That is, the third mixture may be in a gel state by the resin mixture.

Therefore, due to the gel two-component silicone gel resin mixed in the resin mixture, it is possible to form the electromagnetic wave absorber 10 in the gel state without the use of an adhesive or the like. In addition, since the adhesive and the additional tape lamination process are not used, there is an effect of maintaining the characteristics of the electromagnetic wave absorber 10.

In addition, the electromagnetic wave absorber 10 has a self-adhesive force as a sheet in the form of a gel can be easily applied to the appliance.

Meanwhile, the casting process may be performed using a comma, a doctor blade, or the like.

After the casting process, the electromagnetic wave absorber 10 according to the present invention may be formed into a sheet through a cutting process.

As described above, through the above processes, the electromagnetic wave absorber 10 of the present invention can form the electromagnetic wave absorber 10 sheet in a gel-like sheet form, and by not using a tape such as an adhesive, the electromagnetic wave absorber 10 ) Characteristics can be maintained.

Hereinafter, the electromagnetic wave absorber according to the present invention will be described through specific examples.

Example  One

5 is a view showing a backlight assembly using an electromagnetic wave absorber as a first embodiment according to the present invention.

Referring to FIG. 5, the backlight assembly 40 includes a plurality of lamps 420 emitting light, a rear cover 410 capable of accommodating the lamp 420, and a seat on the rear cover 410. And a plurality of optical members 430 and a power supply device 440 for supplying power to the lamp 420, and absorb electromagnetic waves around a device generating electromagnetic waves such as the power supply device 440. And an electromagnetic wave absorber 10, which may be used.

In this case, the electromagnetic wave absorber 10 may be formed in a sheet shape of a gel type and attached to one surface of the rear cover 410.

The backlight assembly 40 is a light providing device that is uniformly used for lighting, advertising boards, liquid crystal displays, etc., and receives power from the power supply 440 to efficiently use light emitted from the lamp 420. It is a lighting device.

Since the lamp 420 emits light, there is considerable heat around the lamp 420. In addition, since the power supply device 440 supplies power to the lamp 420, electromagnetic waves may be generated.

However, since the lamp 420 may operate the lamp 420 even with a pulse wave, electromagnetic waves generated from the power supply device 440 may malfunction the lamp 420.

As described above, the formed backlight assembly 40 may degrade the product quality of the backlight assembly 40 due to malfunction of the lamp 420, heat around the lamp 420, or the like due to the electromagnetic waves.

Thus, the electromagnetic wave absorber 10 according to the present invention may be provided in the backlight assembly 40 to absorb electromagnetic waves generated from the backlight assembly 40.

In addition, by preventing the malfunction of the lamp 420, it is possible to absorb the electromagnetic waves harmful to the human body to protect the commercial user from the pollution of harmful electromagnetic waves.

The electromagnetic wave absorber 10 absorbs electromagnetic waves and converts the absorbed electromagnetic waves into heat to emit the electromagnetic waves. That is, since the electromagnetic wave absorber 10 according to the present invention is a material having excellent thermal conductivity, the electromagnetic wave absorber 10 may emit heat generated from the lamp 420.

Here, the electromagnetic wave absorber 10 may be formed around the power supply device 440 as shown in the drawing, or may be formed of a mold forming the rear cover 410.

Example  2

6 is a view showing a liquid crystal display device using an absorber for electromagnetic waves according to a second embodiment of the present invention.

The liquid crystal display may be formed of a liquid crystal panel having a backlight assembly and a liquid crystal. The backlight assembly will be described with reference to FIG. 5.

The liquid crystal display device is a display device capable of displaying an image by the light transmitted by operating the liquid crystal.

Referring to FIG. 6, the liquid crystal display device 50 includes a liquid crystal panel 510 and a backlight assembly 40 on the rear surface of the liquid crystal panel 510.

Here, since the backlight assembly has been described with reference to FIG. 5, it will be omitted or briefly described.

The liquid crystal panel 510 is formed with a plurality of metal wires, and provides a signal to the metal wires to operate the liquid crystal. The operating liquid crystal transmits light, and the transmitted light displays an image that can be seen by the user.

The signal provided to the liquid crystal panel 510 is provided with a pulse wave, and the pulse wave operates the liquid crystal in the liquid crystal panel 510.

As such, the provided signal generates electromagnetic waves and a user who views an image with the liquid crystal display 50 is exposed to harmful electromagnetic waves.

Therefore, the present invention provides an electromagnetic wave absorber 10 capable of absorbing electromagnetic waves in the liquid crystal display device 50 to protect a user who uses the liquid crystal display device 50 from harmful electromagnetic waves.

In addition, the electromagnetic wave absorber 10 may have an effect of preventing malfunction of the liquid crystal display device 50, which may occur due to electromagnetic waves.

Although the present invention has been described with reference to the embodiments shown in the drawings, this is merely exemplary, and those skilled in the art to which the art belongs can make various modifications and other equivalent embodiments therefrom. Will understand.

Therefore, the true technical protection scope of the present invention will be defined by the claims below.

1 is a view showing an electromagnetic wave absorber according to the present invention.

Figure 2 is a graph showing the electromagnetic wave absorption characteristics of the electromagnetic wave absorber according to the present invention.

Figure 3 is a graph measuring the thermal conductivity characteristics according to the thickness of the electromagnetic wave absorber according to the present invention.

Figure 4 shows a flow chart for manufacturing the electromagnetic wave absorber according to the present invention.

5 is a view showing a backlight assembly using an electromagnetic wave absorber as a first embodiment according to the present invention;

6 is a view showing a liquid crystal display device using an electromagnetic wave absorber as a second embodiment according to the present invention.

Claims (13)

A polymer matrix comprising a resin mixture comprising a room temperature-curable two-component silicone gel resin and a thermosetting one-component silicone pressure-sensitive adhesive resin, a catalyst for promoting curing of the resin mixture, and a viscosity modifier for adjusting the viscosity of the resin mixture; And Electromagnetic wave absorber comprising a filler mixed in the polymer matrix. The method of claim 1, The two-component silicone gel resin contained in the resin mixture is an electromagnetic wave absorber, characterized in that the vinyl polymethylsiloxane (Vinylpolymethylsiloxane). The method of claim 2, The vinyl polymethylsiloxane (Vinylpolymethylsiloxane) is a two-component silicone gel resin in a total of 100 parts by weight of A (topic), B (curing agent) of 45 parts by weight to 55 parts by weight: 55 parts by weight to 45 parts by weight of An electromagnetic wave absorber, characterized by mixing at a ratio. The method of claim 1 The resin mixture is based on a total of 100 parts by weight of the resin mixture, the two-component silicone material and the thermosetting resin are mixed in a ratio of 90 parts by weight to 97 parts by weight: 10 parts by weight to 3 parts by weight. Electromagnetic wave absorber The method of claim 1, The catalyst is a composition containing a platinum containing compound and carbon black, a composition containing a platinum containing compound and fumed titanium dioxide, a composition containing a platinum containing compound and an azo compound, a composition containing a platinum compound and iron oxide, a platinum containing compound and An electromagnetic wave absorber, which is any one selected from a composition containing a triazole-based compound, a composition containing a platinum-containing compound, a nitrogen-containing organic group and an organosilicon compound containing an unsaturated group. The method of claim 1, Wherein the catalyst is an electromagnetic wave absorber, characterized in that the content of the platinum compound to promote the curing of the resin mixture is mixed in 0.1 to 2 phr (per hundred resin) in a total of 100 parts by weight of the resin mixture. The method of claim 1, The viscosity modifier is an electromagnetic wave absorber, characterized in that using a silicone oil. The method of claim 7, wherein The viscosity modifier is a dimethyl cyclopolysiloxane (dimethyl cyclo-polysiloxane), characterized in that the electromagnetic wave absorber. The method of claim 1, The filler is an electromagnetic wave characterized in that the Ni-Zn ferrite mixed with 6wt% to 8wt% of nickel (Ni), 10wt% to 15wt% of zinc (Zn), and Fe ₂ O ₃ or Fe ₂ O ₄ mixed with the remaining amount. Absorber. The method of claim 9, The Ni-Zn ferrite is an electromagnetic wave absorber, characterized in that further added CuO. The method of claim 1, The filler is an electromagnetic wave absorber, characterized in that formed in the powder form of 1㎛ to 10㎛ size. A backlight assembly comprising an electromagnetic wave absorber formed from any one of claims 1 to 11. A liquid crystal display device comprising an electromagnetic wave absorber formed by any one of claims 1 to 11.

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