KR100459313B1 - Electromagnetic wave absorber composition comprising fe2o3, nio, zno, cuo, water, dispersant, plasticizer and lubricant, its preparation method, paint composition for absorbing electromagnetic wave containing the composition, its preparation method, its coating method, and device using the paint composition - Google Patents

Abstract

PURPOSE: Provided are an electromagnetic wave absorber composition to reduce the electromagnetic wave generated from an electrical or electronic device, its preparation method, a paint composition for absorbing an electromagnetic wave, its preparation method, its coating method, and a device emitting an electromagnetic wave using the paint composition. CONSTITUTION: The electromagnetic wave absorber composition comprises a powder source material comprising 55-65 parts by weight of Fe2O3, 15-20 parts by weight of NiO, 10-15 parts by weight of ZnO and 8-12 parts by weight of CuO; 30-50 parts by weight of water; 0.3-0.5 parts by weight of a dispersant; 0.5-1.0 parts by weight of a plasticizer; and 0.1-0.3 parts by weight of a lubricant. Preferably the plasticizer comprises poly(vinyl alcohol) and Bi2O3; the dispersant comprises hexamethanol; and the lubricant comprises H2ZnO2. The paint composition comprises 45-65 parts by weight of the electromagnetic wave absorber ceramics composition; 8-12 parts by weight of an acryl resin; 20-40 parts by weight of a solvent; and 3-8 parts by weight of an additive.

Description

Electromagnetic wave absorber composition and preparation method thereof, coating composition for electromagnetic wave absorption, preparation method thereof and coating method thereof

The present invention relates to an electromagnetic wave absorber composition, a method for manufacturing the same, a coating composition for absorbing electromagnetic wave, a method for manufacturing the same, and a method for applying the same. More specifically, a mobile phone, a pager, a computer, a wireless telephone, a television, a vacuum cleaner, a humidifier, and a hair Efficiently reduce electromagnetic waves generated by the device by simply attaching it to the inside or outside of the device that emits electromagnetic waves, such as dryers, refrigerators, washing machines, and electric devices of automobiles, or by applying it to the inner or outer walls of the housing of the device that emits electromagnetic waves. The present invention relates to an electromagnetic wave absorber composition, a method for producing the same, a coating composition for absorbing electromagnetic waves, a method for producing the same, and a method for applying the same.

The present invention is an improvement of patent application No. 08 / 735,794, filed by the applicant of October 21, 1996 and currently pending in the United States Patent Office. Invention.

At present, many electric and electronic devices such as mobile phones, pagers, computers, cordless phones, hair dryers, televisions, vacuum cleaners, humidifiers, hair dryers, refrigerators, washing machines, and electric devices of automobiles are used in daily life. . Devices that use such electricity are essential to modern life, but most of them emit electromagnetic waves to the outside. It is well known that electromagnetic waves generated and emitted from devices using electricity have various detrimental effects on the human body using the devices.

According to the safety standards of the Specific Absorption Rate (SAR), which was set in 1982 by the American National Standards Institute (ANSI), if the SAR exceeds 4-8 mW / g, In particular, it can cause thermal disturbances. The specific safety criteria of the specific absorption rate (SAR) are expected to be lower as further studies on electromagnetic interference continue. Recently, countries around the world have already prepared safety standards for Specific Absorption Rate (SAR) to protect the human body from electromagnetic waves.

Therefore, studies are underway to block electromagnetic waves harmful to the human body from the devices. As a result of these studies, an ultrasonic oscillator using ferrite or nickel is mounted on the front of the device. A method of blocking electromagnetic waves reaching the human body is disclosed. Also disclosed is a method of wrapping the device with copper or packaging the device in a case made of yttrium oxide (Y ₂ O ₃ ).

However, conventional methods for blocking electromagnetic waves are difficult to sufficiently reduce the electromagnetic waves generated from the electrical and electronic devices, and there is a problem in that the configuration of the device is complicated or the manufacturing cost is high.

Accordingly, a first object of the present invention is to provide an electromagnetic wave absorber composition which can effectively reduce the electromagnetic wave generated and emitted from the device by simply attaching it to the inside or the outside of the various devices emitting the electromagnetic wave.

It is a second object of the present invention to provide a method for producing an electromagnetic wave absorber composition, which is particularly suitable for producing the composition.

It is a third object of the present invention to provide a coating composition for absorbing electromagnetic waves, which can significantly reduce electromagnetic waves generated from the device by applying to the inner wall twisted outer wall of the case of the device for emitting electromagnetic waves.

A fourth object of the present invention is to provide a method for producing an electromagnetic wave absorbing coating composition, which is particularly suitable for producing the electromagnetic wave absorbing coating composition.

A fifth object of the present invention is to provide a coating method of the electromagnetic wave absorbing coating composition, which is particularly suitable for applying the electromagnetic wave absorbing coating composition to the inner wall or the outer wall of the case of the device for emitting electromagnetic waves.

In order to achieve the first object of the present invention described above,

In a powder raw material comprising 55 to 65 parts by weight of iron oxide (Fe ₂ O ₃ ), 15 to 20 parts by weight of nickel oxide (NiO), 10 to 15 parts by weight of zinc oxide (ZnO), and 8 to 12 parts by weight of copper oxide (CuO). And 30 to 50 parts by weight of water, 0.3 to 0.5 parts by weight of dispersant, 0.5 to 1.0 parts by weight of plasticizer, and 0.1 to 0.3 parts by weight of lubricant based on the powder raw material.

Preferably, the content of iron oxide is 58 to 62 parts by weight, and the content of nickel oxide is 18 to 19 parts by weight. The plasticizer includes polyvinyl alcohol and arsenic oxide (Bi ₂ O ₃ ), the dispersant includes hexamethanol, and the lubricant includes zinc acid (H ₂ ZnO ₂ ).

In order to achieve the second object of the present invention described above,

In a powder raw material comprising 55 to 65 parts by weight of iron oxide (Fe ₂ O ₃ ), 15 to 20 parts by weight of nickel oxide (NiO), 10 to 15 parts by weight of zinc oxide (ZnO), and 8 to 12 parts by weight of copper oxide (CuO). 30 to 50 parts by weight of water, 0.3 to 0.5 parts by weight of dispersant, 0.5 to 1.0 parts by weight of polyvinyl alcohol, 0.0005 to 0.004 parts by weight of arsenic oxide (Bi ₂ O ₃ ), and 0.1 to 0.3 parts by weight of lubricant. Mixing uniformly;

Grinding the mixed raw materials to form powder;

Spray drying the pulverized powder to form granular powder;

Molding the granular powder to form a molded body;

Sintering the molded body to form a sintered body; And

It provides a method for producing an electromagnetic wave absorber composition comprising the step of cooling the sintered body.

In order to achieve the third object of the present invention described above,

Powder raw material composed of 55 to 65 parts by weight of iron oxide (Fe ₂ O ₃ ), 15 to 20 parts by weight of nickel oxide (NiO), 10 to 15 parts by weight of zinc oxide (ZnO), and 8 to 12 parts by weight of copper oxide (CuO); 45 to 65 parts by weight of the ceramic composition comprising 30 to 50 parts by weight of water, 0.2 to 0.6 parts by weight of dispersant, 0.5 to 1.0 part by weight of plasticizer, and 0.1 to 0.4 part by weight of lubricant; And

Provided is a coating composition for absorbing electromagnetic waves, comprising 8 to 12 parts by weight of acrylic resin, 20 to 40 parts by weight of solvent, and 3 to 8 parts by weight of an additive with respect to the ceramic composition.

Preferably, the said solvent contains 50-90 weight part of true solvents, and 10-50 weight part of diluents. The diluent comprises 20 to 40 parts by weight of ketone and 30 to 50 parts by weight of ester, and the diluent includes 5 to 30 parts by weight of alcohol and 5 to 20 parts by weight of aliphatic hydrocarbon.

In order to achieve the fourth object of the present invention described above, the present invention,

Powder raw material composed of 55 to 65 parts by weight of iron oxide (Fe ₂ O ₃ ), 15 to 20 parts by weight of nickel oxide (NiO), 10 to 15 parts by weight of zinc oxide (ZnO), and 8 to 12 parts by weight of copper oxide (CuO); 30 to 50 parts by weight of water, 0.2 to 0.6 parts by weight of dispersant, 0.5 to 1.0 parts by weight of plasticizer, and 0.1 to 0.4 parts by weight of lubricant based on the powder raw material;

Grinding the mixed raw materials to form a first powder;

Spray drying the pulverized first powder to form granular powder;

Sintering the granular powder to form a sintered body;

Cooling the sintered body;

Grinding the cooled sintered compact to form a second powder; And

It provides a method for producing a coating composition for absorbing electromagnetic waves comprising the step of uniformly mixing the second powder and acrylic resin, a solvent, and an additive.

The step of pulverizing the mixed raw material to form a first powder is a step of forming a first powder having a particle size of 1 to 3㎛ by wet grinding for 2 to 4 hours using a ball mill, Spray drying the pulverized first powder to form granular powder may be achieved by maintaining the inlet temperature of the spray dryer at 550 to 600 ° C. and the outlet temperature of the spray dryer at 100 to 150 ° C. in the granular powder. It is a step which makes water content into 0.1-0.4 weight part with respect to the said granular powder.

Forming the second powder is a step of forming a second powder having a particle size of 5 to 15㎛ by grinding for 2 to 4 hours using a ball mill, the step of forming the sintered body, i) the granules Loading the mold powder into a kiln and heating it to a temperature of 400 ° C. for 3 hours, ii) maintaining the temperature of the kiln at 400 ° C. for 1 hour, i) maintaining the temperature of the kiln from 400 ° C. to 900 ° C. Heating for 4 hours, i) maintaining the temperature of the kiln at 900 ° C. for 2 hours, iii) heating the temperature of the kiln for 3 hours from 900 ° C. to 1200 ° C., and iii) The method may further include maintaining the temperature of the kiln at 1200 ° C. for 2 hours.

The cooling of the sintered body may include: slowly cooling the sintered body loaded in the sintering furnace for 40 to 60 hours after sealing the sintering furnace, and removing the sintered body loaded in the sintering furnace at a temperature of 200 ° C. or lower, thereby natural It further comprises the step of cooling.

Preferably, the step of uniformly mixing the second powder and acrylic resin, solvent, and additives to form a paint, 45 to 65 parts by weight of the second powder, 8 to 12 weight of acrylic resin relative to the second powder It is a step of mixing parts, 20 to 40 parts by weight of the solvent, and 3 to 8 parts by weight of the additive.

And, in order to achieve the fifth object of the present invention described above,

Provided is a method for applying an electromagnetic wave absorbing coating composition according to claim 10, wherein the coating composition for absorbing electromagnetic waves is sprayed to an inner wall or an outer wall of a case of an apparatus for emitting electromagnetic waves in a thickness of 15 to 40 µm.

Preferably, the coating method of the electromagnetic wave absorbing coating composition is a spray gun having a diameter of 1.3 to 1.5 mm at a spray pressure of 3 to 5 kg / cm 2 to obtain the electromagnetic wave absorbing coating composition. Spraying the inner or outer walls of the case of the device for emitting electromagnetic waves and drying the sprayed electromagnetic wave absorbing coating composition at a temperature of 30 to 40 ° C. for 10 to 15 minutes.

55 to 65 parts by weight of iron oxide, 15 to 20 parts by weight of nickel oxide, 10 to 15 parts by weight of zinc oxide, and 8 to 12 parts by weight of copper oxide are mixed and sintered to produce an electromagnetic wave absorber composition, followed by Hyundai Electronics Co., Ltd. When the electromagnetic wave absorber composition is attached to a predetermined position of the antenna portion of the cellular phone manufactured by, the measured value of Specific Absorption Rate (SAR) of the electromagnetic wave generated from the cellular phone in the folded state (IN state) of the cellular phone is 1.72 It was -1.78 mW / g, about 29.6%-31.5% compared with 2.50-2.53 mW / g which is the measured value of specific absorption rate (SAR) before attaching the said electromagnetic wave absorber composition to a mobile phone. In addition, after attaching the electromagnetic wave absorber composition to the mobile phone, the measured value of the specific absorption rate of the electromagnetic wave generated from the mobile phone in the open state (out state) of the mobile phone is 1.36 to 1.37mW / g, the composition to the mobile phone It decreased by about 19.9% to 21.4% compared to 1.71 to 1.73 mW / g, which is a measured value of the specific absorption rate before deposition.

Therefore, the electromagnetic wave absorber composition according to the present invention is the inside or outside of the device for emitting electromagnetic waves, such as mobile phones, pagers, computers, cordless phones, televisions, vacuum cleaners, humidifiers, hair dryers, refrigerators, washing machines, and electric devices of automobiles. By simply attaching to the device, electromagnetic waves harmful to the human body from the devices can be significantly reduced.

In addition, the ceramic composition is 45 to 65 parts by weight, and 8 to 12 parts by weight of acrylic resin, 20 to 40 parts by weight of solvent, and 3 to 8 parts by weight of additives are mixed with the ceramic composition to prepare a coating composition. When the coating composition is applied to the outside of the mobile phone emitting a thickness of 20 to 35㎛, the measured value of Specific Absorption Rate (SAR) of electromagnetic waves generated from the mobile phone while the antenna of the mobile phone is folded (IN state) It was 0.21-1.72 mW / g, about 32.0%-97.3% decrease compared with 2.50-2.53 mW / g which is the measured value of specific absorption rate (SAR) before apply | coating the said coating composition to a mobile phone. In addition, the measured value of the specific absorption rate of the electromagnetic wave generated from the mobile phone in the open state (out state) of the mobile phone is 0.12-1.16mW / g, which is a measured value of the specific absorption rate before applying the coating composition to the mobile phone. It was reduced by about 32.2% to 93.0% compared to -1.73 mW / g.

Particularly, the ceramic composition is 50 parts by weight, and 10 parts by weight of acrylic resin, 35 parts by weight of solvent, and 5 parts by weight of additives are mixed with the ceramic composition to prepare a coating composition, and then the outer wall of the case of the mobile phone emitting electromagnetic waves. When the coating composition was coated to have a thickness of about 35 μm, the measured value of specific absorption rate of electromagnetic waves generated from the mobile phone in the folded state (IN state) of the mobile phone was 0.21 mW / g, which is a measured value before application. It was reduced by about 91.7% compared to 2.52 mW / g, and the measured value of specific absorption rate of electromagnetic wave generated from the mobile phone in the open state (out state) of the mobile phone was 0.12 mW / g, which is 1.71 which is the measured value before application. The effect was the highest with about 93.0% reduction compared to mW / g.

Therefore, the electromagnetic wave absorbing coating composition according to the present invention can be conveniently applied to the inner wall or the outer wall of a case of a device that emits electromagnetic waves such as mobile phones, pagers, computers, cordless phones, televisions, and electric / electronic devices such as electric devices of automobiles. Application can significantly reduce electromagnetic waves harmful to the human body generated from the devices and emitted to the outside.

EMBODIMENT OF THE INVENTION Hereinafter, an electromagnetic wave absorber composition, a method for manufacturing the same, a material for absorbing electromagnetic waves, a method for manufacturing the same, and a method for applying the same will be described in detail with reference to the embodiments. However, the following examples do not limit or limit the present invention.

Example 1

The powder raw material in a raw powder consisting of 60 parts by weight of iron oxide (Fe ₂ O ₃ ), 18 parts by weight of nickel oxide (NiO), 12 parts by weight of zinc oxide (ZnO), and 10 parts by weight of copper oxide (CuO) 40 parts by weight of water was added, hexamethanol was added as a dispersant, 0.4 parts by weight of the powder raw material, 0.75 parts by weight of polyvinyl alcohol and 0.001 parts by weight of arsenic oxide (Bi ₂ O ₃ ) were added as a plasticizer. 0.2 parts by weight of zinc acid (H ₂ ZnO ₂ ) was added and mixed uniformly.

The iron oxide, the nickel oxide, the zinc oxide, and the copper oxide used powders produced by Kyocera Co., Ltd., Japan, and the dispersant and plasticizer used products manufactured by Sanop Co., Ltd., Japan.

Subsequently, the mixed raw materials were wet pulverized for 2 to 4 hours using a ball mill, and then spray-dried to prepare granular powder having a particle size of about 1 to 3 μm. At this time, while preparing the granular powder, the inlet temperature of the spray dryer is maintained at 550-600 ° C., and the outlet temperature of the spray dryer is maintained at 100-150 ° C. to maintain the moisture in the powder. Content was made into 0.2 to 0.3 weight part. As a result, granular powder having a density of 1.05 to 1.13 g / cm 3 was produced.

Then, the granular powder was molded in a mold press at a pressure of 1000 kg / cm 2 at room temperature to obtain a shaped body having a density of 1.15 to 1.23 g / cm 3. Subsequently, the molded body was placed in a furnace and sintered in six steps for 15 hours in a nitrogen (N ₂ ) atmosphere as follows. First, the molded body was loaded into a firing furnace in a first step and heated to a temperature of 400 ° C. for 3 hours, and then the temperature of the firing furnace was fixed at 400 ° C. for 1 hour in a second step. Next, in the third step, the temperature of the kiln was heated for 4 hours from 400 ° C to 900 ° C, and then maintained in the fourth step at a temperature of 900 ° C for 2 hours. The molded body was sintered in a fifth step by heating the kiln for 3 hours from 900 ° C. to 1200 ° C., followed by maintaining the temperature of the kiln in 1200 ° C. for 2 hours.

Thereafter, the kiln was sealed and gradually cooled for 50 hours. When the temperature of the kiln reached 200 ° C. or less, the sintered compact was removed from the kiln, and then naturally cooled to prepare an electromagnetic wave absorber composition having a predetermined shape.

The measured values of Specific Absorption Rate (SAR) of the electromagnetic wave absorber composition according to the present embodiment are shown in Table 1 below. The measured values of the specific absorption rate shown in Table 1 are obtained by attaching the electromagnetic wave absorber composition to a region adjacent to the antenna of a mobile phone manufactured by Hyundai Electronics Co., Ltd. of Korea, and then the specific electromagnetic absorption rate (SAR) manufactured by US IDX System. ) Measured using IDX System, a measuring instrument.

Location of the antenna of the phone Measurement value without attaching the electromagnetic wave absorber composition according to Example 1 to the mobile phone Measured value after attaching the electromagnetic wave absorber composition according to Example 1 to the mobile phone Reduction rate (%) Specific Absorption Rate (SAR) (mW / g) IN status 2.51 1.72 31.5 OUT status 1.73 1.37 20.8

As shown in Table 1, the measured value of the specific absorption rate in the folded state (IN state) of the antenna of the cellular phone after the electromagnetic wave absorber composition according to the present embodiment is attached to a predetermined position adjacent to the antenna of the modern cellular phone is 1.72 mW. As / g, it was reduced by 31.5% compared to 2.51mW / g, which is a measure of the specific absorption rate before the composition was attached to the mobile phone.

In addition, the measured value of the specific absorption rate in the open state (out state) of the antenna of the mobile phone after attaching the electromagnetic wave absorber composition according to the present embodiment at a predetermined position adjacent to the antenna of the modern mobile phone is 1.37 mW / g. It decreased by 20.8% compared to 1.73 mW / g, which is a measured value of specific absorption rate before deposition. Therefore, it can be seen from the results of Table 1 that the electromagnetic wave absorber composition according to the present embodiment sufficiently reduces electromagnetic waves harmful to the human body emitted from the mobile phone. In the present embodiment, the electromagnetic wave absorber composition is attached to a predetermined position adjacent to the antenna of the mobile phone. However, the electromagnetic wave generated from the mobile phone may be reduced by attaching the electromagnetic wave absorber composition to the inside of the mobile phone.

Example 2

To a powder raw material consisting of 62 parts by weight of iron oxide (Fe ₂ O ₃ ), 18 parts by weight of nickel oxide (NiO), 10 parts by weight of zinc oxide (ZnO), and 10 parts by weight of copper oxide (CuO), water 40 Add weight parts, add 0.4 parts by weight of hexamethanol to the powder raw material as a dispersant, add 0.75 parts by weight of polyvinyl alcohol and 0.001 parts by weight of arsenic oxide (Bi ₂ O ₃ ) as a plasticizer, and then add zinc acid ( 0.2 parts by weight of H ₂ ZnO ₂ ) was added and mixed uniformly.

In this embodiment, the raw materials used the same product as in the case of Example 1 of the present invention described above.

The mixed raw materials were wet milled for 2 to 4 hours using a ball mill, and then spray dried to prepare granular powder having a particle size of about 1 to 3 μm. At this time, while preparing the granular powder, the inlet temperature of the spray dryer is maintained at 550-600 ° C., and the outlet temperature of the spray dryer is maintained at 100-150 ° C. so that the water content in the powder is 0.2-0.3. It was made to be a weight part. As a result, granular powder having a density of 1.05 to 1.13 g / cm 3 was produced.

Then, the granular powder was molded in a mold press at a pressure of 1000 kg / cm 2 at room temperature to obtain a shaped body having a density of 1.15 to 1.23 g / cm 3. Subsequently, the molded body was placed in a sintering furnace and sintered in six steps for 15 hours in a nitrogen atmosphere as follows. In the first step, the molded body was loaded into a firing furnace and heated to a temperature of 400 ° C. for 3 hours, and then, in the second step, the temperature of the firing furnace was fixed at 400 ° C. for 1 hour. Next, in the third step, the temperature of the kiln was heated for 4 hours from 400 ° C to 900 ° C, and then maintained in the fourth step at a temperature of 900 ° C for 2 hours. The molded body was sintered in a fifth step by heating the kiln for 3 hours from 900 ° C. to 1200 ° C., followed by maintaining the temperature of the kiln in 1200 ° C. for 2 hours.

Thereafter, the kiln was sealed and gradually cooled for 50 hours. When the temperature of the kiln reached 200 ° C. or less, the sintered compact was removed from the kiln, and then naturally cooled to prepare an electromagnetic wave absorber composition having a predetermined shape.

The measured values of Specific Absorption Rate (SAR) of the electromagnetic wave absorber composition according to the present embodiment are shown in Table 2 below. The measured values of the specific absorption rate shown in Table 2 are attached to the area adjacent to the antenna of the mobile phone manufactured by Hyundai Electronics Co., Ltd., and then measured by the US IDX System. Measured using the IDX System.

Location of the antenna of the phone Measurement value without attaching the electromagnetic wave absorber composition according to Example 2 to the mobile phone Measured value after attaching the electromagnetic wave absorber composition according to Example 2 to the mobile phone Reduction rate (%) Specific Absorption Rate (SAR) (mW / g) IN status 2.53 1.75 30.8 OUT status 1.73 1.36 21.4

As shown in Table 2, the measured value of the specific absorption rate is 1.75mW in the folded state (IN state) of the antenna of the mobile phone after attaching the electromagnetic wave absorber composition according to the present embodiment at a predetermined position adjacent to the antenna of the modern mobile phone. As / g, it decreased by 30.8% compared to 2.53mW / g, which is a measure of the specific absorption rate before the composition was attached to the mobile phone. In addition, the measured value of the specific absorption rate in the state in which the antenna of the cellular phone is extended (OUT state) after attaching the electromagnetic wave absorber composition according to the present embodiment at a predetermined position adjacent to the antenna of the modern cellular phone is 1.36 mW / g. It decreased by 21.4% compared to 1.73 mW / g, which is a measured value of the specific absorption rate before deposition.

Therefore, it can be seen from the results of Table 2 that the electromagnetic wave absorber composition according to the present embodiment sufficiently reduces electromagnetic waves harmful to the human body emitted from the mobile phone. In the present embodiment, the electromagnetic wave absorber composition is attached to a predetermined position adjacent to the antenna of the mobile phone. However, the electromagnetic wave generated from the mobile phone may be reduced by attaching the electromagnetic wave absorber composition to the inside of the mobile phone.

Example 3

In a powder raw material consisting of 58 parts by weight of iron oxide (Fe ₂ O ₃ ), 19 parts by weight of nickel oxide (NiO), 13 parts by weight of zinc oxide (ZnO), and 10 parts by weight of copper oxide (CuO), water 40 Add weight parts, add 0.4 parts by weight of hexamethanol to the powder raw material as a dispersant, add 0.75 parts by weight of polyvinyl alcohol and 0.001 parts by weight of arsenic oxide (Bi ₂ O ₃ ) as a plasticizer, and then add zinc acid ( 0.2 parts by weight of H ₂ ZnO ₂ ) was added and mixed uniformly.

In the present embodiment, the raw materials used were the same products as in Example 1 of the present invention, the grinding, molding, sintering and cooling method of the raw material powder is the same as in the case of Example 1.

The measured value of specific absorption rate (SAR) of the electromagnetic wave absorber composition according to the present embodiment is shown in Table 3 below. The measured values of the specific absorption rate shown in Table 3 are attached to the area adjacent to the antenna of the mobile phone manufactured by Hyundai Electronics Co., Ltd., and then the electromagnetic specific absorption rate (SAR) measuring equipment manufactured by US IDX System. Measured using the IDX System.

Location of the antenna of the phone Measurement value without attaching the electromagnetic wave absorber composition according to Example 3 to the mobile phone Measured value after attaching the electromagnetic wave absorber composition according to Example 3 to the mobile phone Reduction rate (%) Specific Absorption Rate (SAR) (mW / g) IN status 2.50 1.74 30.4 OUT status 1.71 1.36 20.5

As shown in Table 3, the measured value of the specific absorption rate in the folded state (IN state) of the antenna of the cellular phone after attaching the electromagnetic wave absorber composition according to the present embodiment at a predetermined position adjacent to the antenna of the modern cellular phone is 1.74 mW. As / g, it was reduced by 30.4% compared to 2.50mW / g, which is a measure of the specific absorption rate before the composition was attached to the mobile phone. In addition, the measured value of the specific absorption rate in the state in which the antenna of the cellular phone is extended (OUT state) after attaching the electromagnetic wave absorber composition according to the present embodiment at a predetermined position adjacent to the antenna of the modern cellular phone is 1.36 mW / g. It decreased by 20.5% compared to 1.71 mW / g, which is a measured value of specific absorption rate before deposition.

Therefore, it can be seen from the results of Table 3 that the electromagnetic wave absorber composition according to the present embodiment sufficiently reduces electromagnetic waves harmful to the human body emitted from the mobile phone.

Example 4

To a powder raw material consisting of 55 parts by weight of iron oxide (Fe ₂ O ₃ ), 20 parts by weight of nickel oxide (NiO), 15 parts by weight of zinc oxide (ZnO), and 10 parts by weight of copper oxide (CuO), water 40 Add weight parts, add 0.4 parts by weight of hexamethanol to the powder raw material as a dispersant, add 0.75 parts by weight of polyvinyl alcohol and 0.001 parts by weight of arsenic oxide (Bi ₂ O ₃ ) as a plasticizer, and then add zinc acid ( 0.2 parts by weight of H ₂ ZnO ₂ ) was added and mixed uniformly.

In the present embodiment, the raw materials used were the same products as in Example 1 of the present invention, the grinding, molding, sintering and cooling method of the raw material powder is the same as in the case of Example 1.

The measured values of specific absorption rate (SAR) of the electromagnetic wave absorber composition according to the present embodiment are shown in Table 4 below. The measured values of the specific absorption rate shown in Table 4 are obtained by attaching the electromagnetic wave absorber composition to a region adjacent to the antenna of a mobile phone manufactured by Hyundai Electronics Co., Ltd., and then measuring the specific absorption rate (SAR) equipment manufactured by the US IDX System. Measured using the IDX System.

Location of the antenna of the phone Measurement value without attaching the electromagnetic wave absorber composition according to Example 4 to the mobile phone Measured value after attaching the electromagnetic wave absorber composition according to Example 4 to the mobile phone Reduction rate (%) Specific Absorption Rate (SAR) (mW / g) IN status 2.53 1.78 29.6 OUT status 1.71 1.37 19.9

As shown in Table 4, the measured value of the specific absorption rate in the folded state (IN state) of the antenna of the cellular phone after attaching the electromagnetic wave absorber composition according to the present embodiment at a predetermined position adjacent to the antenna of the modern cellular phone is 1.78 mW. As / g, it was reduced by 29.6% compared to 2.53mW / g, which is a measure of the specific absorption rate before attaching the composition to a mobile phone. In addition, the measured value of the specific absorption rate in the open state (out state) of the antenna of the mobile phone after attaching the electromagnetic wave absorber composition according to the present embodiment at a predetermined position adjacent to the antenna of the modern mobile phone is 1.37 mW / g. It decreased by 19.9% compared with 1.71 mW / g, which is a measured value of specific absorption rate before deposition.

Therefore, it can be seen from the results of Table 4 that the electromagnetic wave absorber composition according to the present embodiment sufficiently reduces electromagnetic waves harmful to the human body emitted from the mobile phone.

Example 5

In a powder raw material consisting of 63 parts by weight of iron oxide (Fe ₂ O ₃ ), 17 parts by weight of nickel oxide (NiO), 10 parts by weight of zinc oxide (ZnO), and 10 parts by weight of copper oxide (CuO), water 40 Add weight parts, add 0.4 parts by weight of hexamethanol to the powder raw material as a dispersant, add 0.75 parts by weight of polyvinyl alcohol and 0.001 parts by weight of arsenic oxide (Bi ₂ O ₃ ) as a plasticizer, and then add zinc acid ( 0.2 parts by weight of H ₂ ZnO ₂ ) was added and mixed uniformly.

In the present embodiment, the raw materials used were the same products as in Example 1 of the present invention, the grinding, molding, sintering and cooling method of the raw material powder is the same as in the case of Example 1.

The measured values of specific absorption rate (SAR) of the electromagnetic wave absorber composition according to the present embodiment are shown in Table 5 below. The measured values of the specific absorption rate shown in Table 5 are attached to the area adjacent to the antenna of the mobile phone manufactured by Hyundai Electronics Co., Ltd., and then the electromagnetic specific absorption rate (SAR) measurement equipment manufactured by the US IDX System. Measured using the IDX System.

Location of the antenna of the phone Measurement value without attaching the electromagnetic wave absorber composition according to Example 5 to the mobile phone Measured value after attaching the electromagnetic wave absorber composition according to Example 5 to the mobile phone Reduction rate (%) Specific Absorption Rate (SAR) (mW / g) IN status 2.51 1.74 30.7 OUT status 1.72 1.37 20.3

As shown in Table 5, the measured value of specific absorption rate in the folded state (IN state) of the cellular phone after the electromagnetic wave absorber composition according to the present embodiment is attached to a predetermined position adjacent to the antenna of the modern cellular phone is 1.74 mW. As / g, it was reduced by 30.7% compared to 2.51mW / g, which is a measure of the specific absorption rate before attaching the composition to a mobile phone. In addition, the measured value of the specific absorption rate in the open state (out state) of the antenna of the mobile phone after attaching the electromagnetic wave absorber composition according to the present embodiment at a predetermined position adjacent to the antenna of the modern mobile phone is 1.37 mW / g. It decreased by 20.3% compared to 1.72 mW / g, which is a measured value of specific absorption rate before deposition.

Therefore, it can be seen from the results of Table 5 that the electromagnetic wave absorber composition according to the present embodiment sufficiently reduces electromagnetic waves harmful to the human body emitted from the mobile phone.

Example 6

To a powder raw material consisting of 60 parts by weight of iron oxide (Fe ₂ O ₃ ), 18 parts by weight of nickel oxide (NiO), 12 parts by weight of zinc oxide (ZnO), and 10 parts by weight of copper oxide (CuO), water 40 Add weight parts, add 0.4 parts by weight of hexamethanol to the powder raw material as a dispersant, add 0.75 parts by weight of polyvinyl alcohol and 0.001 parts by weight of arsenic oxide (Bi ₂ O ₃ ) as a plasticizer, and then add zinc acid ( 0.2 parts by weight of H ₂ ZnO ₂ ) was added and mixed uniformly.

In this embodiment, the raw materials used the same product as in the case of Example 1 of the present invention described above. Subsequently, the mixed raw materials are wet pulverized for 2 to 4 hours using a ball mill to prepare a first powder, and then spray-drying the first powder to about 1 to 3 μm. A granular powder having a particle size of was prepared. At this time, while preparing the granular powder, the inlet temperature of the spray dryer is maintained at about 550 to 600 ° C, and the outlet temperature of the spray dryer is maintained at about 100 to 150 ° C. The moisture content in it was made to be 0.2-0.3 weight part. As a result, granular powder having a density of 1.05 to 1.13 g / cm 3 was produced.

Subsequently, the granular powder was placed in a furnace and sintered in six steps for 15 hours in a nitrogen (N ₂ ) atmosphere as follows. First, the granular powder was loaded into a kiln in a first step and heated to a temperature of 400 ° C. for 3 hours, and then the temperature of the kiln was fixed at 400 ° C. for 1 hour in a second step. Next, in the third step, the temperature of the kiln was heated for 4 hours from 400 ° C to 900 ° C, and then maintained in the fourth step at a temperature of 900 ° C for 2 hours. In the fifth step, the temperature of the kiln was heated for 3 hours to reach 900 ° C to 1200 ° C, and in the sixth step, the temperature of the kiln was maintained at 1200 ° C for 2 hours to sinter the granular powder.

Thereafter, the kiln was sealed and gradually cooled for 50 hours. When the temperature of the kiln reached 200 ° C or less, the sintered compact was taken out of the kiln, and then naturally cooled. Subsequently, the sintered compact was ground for 1 to 3 hours using a ball mill to prepare a second powder having a particle size of 5 to 15 µm, preferably about 8 to 10 µm. Subsequently, 50 parts by weight of the second powder, 10 parts by weight of acrylic resin, 35 parts by weight of solvent, and 5 parts by weight of additives are uniformly mixed with the second powder to absorb the electromagnetic wave. The composition was prepared. The solvent used was composed of 70 parts by weight of true solvent and 30 parts by weight of diluent. The diluent used was 30 parts by weight of ketone and 40 parts by weight of ester, and the diluent used was 20 parts by weight of alcohol and 10 parts by weight of aliphatic hydrocarbon.

Subsequently, the coating composition for absorbing electromagnetic waves was applied to the outer wall of the case of a mobile phone manufactured by Hyundai Electronics Co., Ltd. of Korea in a space of about 15 to 20 cm using a spray gun. At this time, the electromagnetic wave absorbing coating composition was applied to the outer wall of the case of the mobile phone around the antenna portion of the mobile phone to have a uniform thickness of about 20 ~ 35㎛.

In order to apply the electromagnetic wave absorbing coating composition, a spray gun having a diameter of about 1.3 to 1.5 mm at a spray pressure of 3 to 5 kg / cm 2 was first sprayed onto the outer wall of the case of the mobile phone. The sprayed electromagnetic wave coating composition was dried at a temperature of about 30 to 40 ° C. for about 10 to 15 minutes to fix the coating composition to the outer wall of the case of the mobile phone.

The measured values of specific absorption rate (SAR) of the coating composition according to the present embodiment are shown in Table 6 below. The measured values of specific absorption rate shown in Table 6 were measured using IDX System, an electromagnetic specific absorption rate (SAR) measuring device manufactured by IDX System, Inc., USA.

Location of the antenna of the phone Measurement value without applying the coating composition according to Example 6 to the mobile phone Measured value by thickness of the coating film after applying the coating composition according to Example 6 to the mobile phone % Reduction Specific Absorption Rate (SAR) (mW / g) IN status 2.52 Thickness of Coating Film (㎛) 35 0.21 91.7 30 0.23 90.9 25 1.29 48.8 20 1.63 35.3 OUT status 1.71 35 0.12 93.0 30 0.15 91.2 25 0.99 42.1 20 1.06 38.0

As shown in Table 6, the antenna of the mobile phone folded after uniformly applying the electromagnetic wave absorbing coating composition of the present embodiment to a thickness of about 20 ~ 35㎛ on the outer wall of the case of the modern mobile phone (IN state ), The specific absorption rate was 0.21 to 1.63 mW / g, which was reduced by about 35.3 to 97.2% compared to 2.52 mW / g, which is a measurement of the specific absorption rate before the coating composition was applied to a mobile phone.

In addition, the measured value of the specific absorption rate in the state in which the antenna of the mobile phone is extended (OUT state) is 0.12 to 1.06 mW / g, which is about 38.0 to 93.0 compared to 1.71 mW / g, which is the measured value of the specific absorption rate before applying the coating composition. % Decrease. Therefore, it can be seen from the results of Table 6 that the electromagnetic wave absorbing coating composition according to the present embodiment significantly reduces electromagnetic waves harmful to the human body emitted from the mobile phone. In the present embodiment, the coating composition is applied to the outer wall of the case of the mobile phone, but the electromagnetic wave generated from the mobile phone may be reduced by coating the coating composition on the inner wall of the mobile phone case.

Example 7

To a powder raw material consisting of 62 parts by weight of iron oxide (Fe ₂ O ₃ ), 18 parts by weight of nickel oxide (NiO), 10 parts by weight of zinc oxide (ZnO), and 10 parts by weight of copper oxide (CuO), water 40 Add weight parts, add 0.4 parts by weight of hexamethanol to the powder raw material as a dispersant, add 0.75 parts by weight of polyvinyl alcohol and 0.001 parts by weight of arsenic oxide (Bi ₂ O ₃ ) as a plasticizer, and then add zinc acid ( 0.2 parts by weight of H ₂ ZnO ₂ ) was added and mixed uniformly.

In this embodiment, the raw materials used the same product as in the case of Example 6 of the present invention described above. The method of preparing the first powder by pulverizing the raw powder, the method of manufacturing the sintered body by sintering and cooling the first powder, and the method of manufacturing the second powder by pulverizing the sintered body are the same as in Example 6. Do.

Subsequently, 53 parts by weight of the second powder, 10 parts by weight of acrylic resin, 32 parts by weight of solvent, and 5 parts by weight of additives were uniformly mixed to prepare a coating composition for absorbing electromagnetic waves. The composition of the said solvent is the same as that of Example 6.

Subsequently, the electromagnetic wave absorbing coating composition was applied to the outer wall of the case of the cellular phone manufactured by Hyundai Electronics Co., Ltd. at intervals of about 15 to 20 cm using a spray gun. In this case, the electromagnetic wave absorbing coating composition is applied to the outer wall of the case of the mobile phone around the antenna portion of the mobile phone to have a uniform thickness of about 20 ~ 35㎛. The method of applying the coating composition for absorbing electromagnetic waves is also the same as in Example 6.

The measured values of specific absorption rate (SAR) of the coating composition according to the present embodiment are shown in Table 7 below. The measured values of specific absorption rate shown in Table 7 were measured using IDX System, an electromagnetic specific absorption rate (SAR) measuring device manufactured by US IDX System.

Location of the antenna of the phone Measurement value without applying the coating composition according to Example 7 to the mobile phone Measured value by thickness of the coating film after applying the coating composition according to Example 7 to the mobile phone % Reduction Specific Absorption Rate (SAR) (mW / g) IN status 2.50 Thickness of Coating Film (㎛) 35 0.25 90.0 30 0.26 89.6 25 1.34 46.4 20 1.61 35.6 OUT status 1.72 35 0.14 91.9 30 0.17 90.1 25 0.90 47.7 20 1.09 36.6

As shown in Table 7, a state in which the antenna of the cellular phone is folded after uniformly applying the electromagnetic wave absorbing coating composition of the present embodiment to a thickness of about 20 to 35 μm on the outer wall of the case of the modern cellular phone (IN state) ), The specific absorption rate was 0.25 to 1.61 mW / g, which was reduced by about 35.6 to 90.0% compared to 2.50 mW / g, which is a measurement of the specific absorption rate before the coating composition was applied to a mobile phone.

In addition, the measured value of the specific absorption rate in the state in which the antenna of the mobile phone is extended (OUT state) is 0.14 to 1.09 mW / g, which is about 36.6 to 99.1 compared to 1.72 mW / g which is the measured value of the specific absorption rate before applying the coating composition. % Decrease. Therefore, it can be seen from the results of Table 7 that the electromagnetic wave absorbing coating composition according to the present embodiment significantly reduces electromagnetic waves harmful to the human body emitted from the mobile phone. In the present embodiment, the coating composition is applied to the outer wall of the case of the mobile phone, but the electromagnetic wave generated from the mobile phone may be reduced by coating the coating composition on the inner wall of the mobile phone case.

Example 8

In a powder raw material consisting of 58 parts by weight of iron oxide (Fe ₂ O ₃ ), 19 parts by weight of nickel oxide (NiO), 13 parts by weight of zinc oxide (ZnO), and 10 parts by weight of copper oxide (CuO), water 40 Add weight parts, add 0.4 parts by weight of hexamethanol to the powder raw material as a dispersant, add 0.75 parts by weight of polyvinyl alcohol and 0.001 parts by weight of arsenic oxide (Bi ₂ O ₃ ) as a plasticizer, and then add zinc acid ( 0.2 parts by weight of H ₂ ZnO ₂ ) was added and mixed uniformly.

In this embodiment, the raw materials used the same product as in the case of Example 6 of the present invention described above. The method of manufacturing the first powder by pulverizing the raw material powder, the method of manufacturing the sintered body by sintering and cooling the first powder, and the method of manufacturing the second powder by pulverizing the sintered body are the same as in Example 6. Do.

Subsequently, 60 parts by weight of the second powder, 10 parts by weight of acrylic resin, 25 parts by weight of solvent, and 5 parts by weight of additives were uniformly mixed to prepare a coating composition for absorbing electromagnetic waves. The composition of the said solvent is the same as that of Example 6.

Subsequently, the electromagnetic wave absorbing coating composition was applied to the outer wall of the case of the cellular phone manufactured by Hyundai Electronics Co., Ltd. at intervals of about 15 to 20 cm using a spray gun. In this case, the electromagnetic wave absorbing coating composition is applied to the outer wall of the case of the mobile phone around the antenna portion of the mobile phone to have a uniform thickness of about 20 ~ 35㎛. The method of applying the coating composition for absorbing electromagnetic waves is also the same as in Example 6.

The measured values of specific absorption rate (SAR) of the coating composition according to the present embodiment are shown in Table 8 below. The measured values of specific absorption rate shown in Table 8 were measured using IDX System, an electromagnetic specific absorption rate (SAR) measuring device manufactured by US IDX System.

Location of the antenna of the phone Measurement value without applying the coating composition according to Example 8 to the mobile phone Measurement value by thickness of coating film after coating coating composition according to Example 8 to mobile phone % Reduction Specific Absorption Rate (SAR) (mW / g) IN status 2.51 Thickness of Coating Film (㎛) 35 0.26 89.6 30 0.32 87.3 25 1.40 44.2 20 1.65 34.3 OUT status 1.72 35 0.16 90.7 30 0.17 90.1 25 0.94 45.3 20 1.13 34.3

As shown in Table 8, the antenna of the mobile phone is folded after uniformly applying the electromagnetic wave absorption coating composition according to the present embodiment to a thickness of about 20 to 35㎛ on the outer wall of the case of the modern mobile phone (IN state ), The specific absorption rate was 0.26 to 1.65 mW / g, which was about 34.3 to 89.6% lower than 2.51 mW / g, which is a measurement of the specific absorption rate before the coating composition was applied to a mobile phone.

In addition, the measured value of the specific absorption rate in the state in which the antenna of the mobile phone is extended (out state) is 0.16-1.13 mW / g, which is about 34.3-90.7 compared to 1.72 mW / g which is the measured value of the specific absorption rate before applying the coating composition. % Decrease. Therefore, it can be seen from the results of Table 8 that the electromagnetic wave absorbing coating composition according to the present embodiment significantly reduces electromagnetic waves harmful to the human body emitted from the mobile phone. In the present embodiment, the coating composition is applied to the outer wall of the case of the mobile phone, but the electromagnetic wave generated from the mobile phone may be reduced by coating the coating composition on the inner wall of the mobile phone case.

Example 9

To a powder raw material consisting of 55 parts by weight of iron oxide (Fe ₂ O ₃ ), 20 parts by weight of nickel oxide (NiO), 15 parts by weight of zinc oxide (ZnO), and 10 parts by weight of copper oxide (CuO), water 40 Add weight parts, add 0.4 parts by weight of hexamethanol to the powder raw material as a dispersant, add 0.75 parts by weight of polyvinyl alcohol and 0.001 parts by weight of arsenic oxide (Bi ₂ O ₃ ) as a plasticizer, and then add zinc acid ( 0.2 parts by weight of H ₂ ZnO ₂ ) was added and mixed uniformly.

In this embodiment, the raw materials used the same product as in the case of Example 6 of the present invention described above. The method of preparing the first powder by pulverizing the raw powder, the method of manufacturing the sintered body by sintering and cooling the first powder, and the method of manufacturing the second powder by pulverizing the sintered body are the same as in Example 6. Do.

Subsequently, 55 parts by weight of the second powder, 10 parts by weight of acrylic resin, 30 parts by weight of solvent, and 5 parts by weight of the additive were uniformly mixed to prepare a coating composition for absorbing electromagnetic waves. The composition of the said solvent is the same as that of Example 6.

Subsequently, the electromagnetic wave absorbing coating composition was applied to the outer wall of the case of the cellular phone manufactured by Hyundai Electronics Co., Ltd. at intervals of about 15 to 20 cm using a spray gun. In this case, the electromagnetic wave absorbing coating composition is applied to the outer wall of the case of the mobile phone around the antenna portion of the mobile phone to have a uniform thickness of about 20 ~ 35㎛. The method of applying the coating composition for absorbing electromagnetic waves is also the same as in Example 6.

The measured values of specific absorption rate (SAR) of the coating composition according to the present embodiment are shown in Table 9 below. The measured values of specific absorption rate shown in Table 9 are measured using IDX System, an electromagnetic specific absorption rate (SAR) measurement device manufactured by IDX System, Inc., USA.

Location of the antenna of the phone Measurement value without applying the coating composition according to Example 9 to the mobile phone Measured value by thickness of the coating film after applying the coating composition according to Example 9 to the mobile phone % Reduction Specific Absorption Rate (SAR) (mW / g) IN status 2.53 Thickness of Coating Film (㎛) 35 0.28 88.9 30 0.33 87.0 25 1.48 41.5 20 1.72 32.0 OUT status 1.71 35 0.18 89.5 30 0.19 88.9 25 0.98 42.7 20 1.16 32.2

As shown in Table 9, a state in which the antenna of the mobile phone is folded after uniformly applying the electromagnetic wave absorption coating composition according to the present embodiment to a thickness of about 20 to 35 μm on the outer wall of the case of the modern mobile phone (IN state) ), The specific absorption rate was 0.28 to 1.72 mW / g, which was about 32.0 to 88.9% lower than 2.53 mW / g, which is the measurement of the specific absorption rate before the coating composition was applied to the mobile phone.

In addition, the measured value of the specific absorption rate in the state in which the antenna of the cellular phone is extended (OUT state) is 0.18-1.16 mW / g, which is about 32.2 to 89.5 compared to 1.71 mW / g which is the measured value of the specific absorption rate before applying the coating composition. % Decrease. Therefore, it can be seen from the results of Table 9 that the electromagnetic wave absorbing coating composition according to the present embodiment significantly reduces electromagnetic waves harmful to the human body emitted from the mobile phone. In the present embodiment, the coating composition is applied to the outer wall of the case of the mobile phone, but the electromagnetic wave generated from the mobile phone may be reduced by coating the coating composition on the inner wall of the mobile phone case.

Example 10

In a powder raw material consisting of 63 parts by weight of iron oxide (Fe ₂ O ₃ ), 17 parts by weight of nickel oxide (NiO), 10 parts by weight of zinc oxide (ZnO), and 10 parts by weight of copper oxide (CuO), water 40 Add weight parts, add 0.4 parts by weight of hexamethanol to the powder raw material as a dispersant, add 0.75 parts by weight of polyvinyl alcohol and 0.001 parts by weight of arsenic oxide (Bi ₂ O ₃ ) as a plasticizer, and then add zinc acid ( 0.2 parts by weight of H ₂ ZnO ₂ ) was added and mixed uniformly.

In this embodiment, the raw materials used the same product as in the case of Example 6 of the present invention described above. The method of preparing the first powder by pulverizing the raw powder, the method of manufacturing the sintered body by sintering and cooling the first powder, and the method of manufacturing the second powder by pulverizing the sintered body are the same as in Example 6. Do.

Subsequently, 58 parts by weight of the second powder, 10 parts by weight of the acrylic resin, 27 parts by weight of the solvent, and 5 parts by weight of the additive were uniformly mixed to prepare a coating composition for absorbing electromagnetic waves. The composition of the said solvent is the same as that of Example 6.

Subsequently, the electromagnetic wave absorbing coating composition was applied to the outer wall of the case of the cellular phone manufactured by Hyundai Electronics Co., Ltd. at intervals of about 15 to 20 cm using a spray gun. In this case, the electromagnetic wave absorbing coating composition is applied to the outer wall of the case of the mobile phone around the antenna portion of the mobile phone to have a uniform thickness of about 20 ~ 35㎛. The method of applying the coating composition for absorbing electromagnetic waves is also the same as in Example 6.

The measured values of specific absorption rate (SAR) of the coating composition according to the present embodiment are shown in Table 10 below. The measured values of specific absorption rate shown in Table 10 were measured using IDX System, an electromagnetic specific absorption rate (SAR) measuring device manufactured by IDX System, Inc., USA.

Location of the antenna of the phone Measurement value without applying the coating composition according to Example 10 on the mobile phone Measured value by thickness of the coating film after applying the coating composition according to Example 10 to a mobile phone % Reduction Specific Absorption Rate (SAR) (mW / g) IN status 2.53 Thickness of Coating Film (㎛) 35 0.24 90.5 30 0.25 90.1 25 1.28 49.4 20 1.58 37.5 OUT status 1.73 35 0.14 91.9 30 0.17 90.2 25 0.89 48.6 20 1.06 38.7

As shown in Table 10, the antenna of the cellular phone folded after uniformly applying the electromagnetic wave absorption coating composition according to the present embodiment to a thickness of about 20 to 35㎛ on the outer wall of the case of the modern mobile phone (IN state ), The specific absorption rate was 0.24 to 1.58 mW / g, which was about 37.5 to 90.5% less than 2.53 mW / g, which is the measurement of the specific absorption rate before the coating composition was applied to a mobile phone.

In addition, the measured value of the specific absorption rate in the state in which the antenna of the mobile phone is extended (out state) is 0.14 to 1.06 mW / g, which is about 38.7 to 99.1 compared to 1.73 mW / g which is the measured value of the specific absorption rate before applying the coating composition. % Decrease. Therefore, it can be seen from the results of Table 10 that the electromagnetic wave absorbing coating composition according to the present embodiment significantly reduces electromagnetic waves harmful to the human body emitted from the mobile phone. In the present embodiment, the coating composition is applied to the outer wall of the case of the mobile phone, but the electromagnetic wave generated from the mobile phone may be reduced by coating the coating composition on the inner wall of the mobile phone case.

The electromagnetic wave absorber composition according to the present invention can be conveniently placed inside or outside a device for emitting electromagnetic waves such as a mobile phone, a pager, a computer, a cordless phone, a television, a vacuum cleaner, a humidifier, a hair dryer, a refrigerator, a washing machine, and an electric device of an automobile. By attaching, it is possible to effectively reduce electromagnetic waves harmful to the human body generated in the device and emitted to the outside.

In addition, the electromagnetic wave absorbing coating composition according to the present invention, mobile phones, pagers, wired and wireless telephones, wired and wireless communication devices, including radios, communication base station equipment and devices, broadcasting equipment and devices, computers, televisions, microwave ovens, hair dryers, Electrical and electronic products, medical instruments and devices, office automation equipment, including electric shavers, blankets and blankets, humidifiers, anion generators, vacuum cleaners, refrigerators, washing machines, fans, air conditioners, audio, electric massagers and massagers, and hearing aids And electrical equipment including motors, control equipment for rotation and distribution, lighting equipment, heating equipment, outlets, electrical materials, desk lamps, power distribution equipment, power distribution lines, power plant equipment, transformers, and measuring equipment using electric and electronic equipment. Electronics such as automobiles and parts thereof, including car car stereos, wiring, connectors, etc. By simply coating a coating material for absorbing electromagnetic waves on the inner wall or outer wall of a case of various electric and electronic devices emitting air waves, the electromagnetic waves emitted from the devices to the outside can be significantly reduced so as not to harm the human body.

Moreover, by using the electromagnetic wave absorbing paint according to the present invention, it is possible to reduce the specific absorption rate of the electromagnetic field and the electromagnetic wave on the human body, as well as to reduce interference and noise between devices such as EMC, EMI, and RFI.

In addition, the electromagnetic wave absorbing paint according to the present invention can be used for shielding a shielding room for measuring, and can also be used for the purpose of blocking electromagnetic waves by spraying on clothing and accessories worn in a laboratory. It can also be applied to shielding cables such as communication lines and distribution lines in a manner such as spraying or powder extrusion to reduce the generation of electromagnetic waves.

In addition, the electromagnetic wave absorbing paint according to the present invention can be used for all products using electric and electronic, as well as can be applied to wallpaper, paint, tiles, etc. of building materials in the same manner as spray coating and powder mixture injection.

Claims (42)

In a powder raw material comprising 55 to 65 parts by weight of iron oxide (Fe ₂ O ₃ ), 15 to 20 parts by weight of nickel oxide (NiO), 10 to 15 parts by weight of zinc oxide (ZnO), and 8 to 12 parts by weight of copper oxide (CuO). 30 to 50 parts by weight of water, 0.3 to 0.5 parts by weight of dispersant, 0.5 to 1.0 parts by weight of plasticizer, and 0.1 to 0.3 parts by weight of lubricant based on the powder raw material. The electromagnetic wave absorber composition according to claim 1, wherein the iron oxide is 58 to 62 parts by weight, and the nickel oxide is 18 to 19 parts by weight. The electromagnetic wave absorber composition of claim 1, wherein the plasticizer comprises polyvinyl alcohol and arsenic oxide (Bi ₂ O ₃ ). The electromagnetic wave absorber composition of claim 1, wherein the dispersant comprises hexamethanol and the lubricant comprises zinc acid (H ₂ ZnO ₂ ). In a powder raw material comprising 55 to 65 parts by weight of iron oxide (Fe ₂ O ₃ ), 15 to 20 parts by weight of nickel oxide (NiO), 10 to 15 parts by weight of zinc oxide (ZnO), and 8 to 12 parts by weight of copper oxide (CuO). 30 to 50 parts by weight of water, 0.3 to 0.5 parts by weight of dispersant, 0.5 to 1.0 parts by weight of polyvinyl alcohol, 0.0005 to 0.004 parts by weight of arsenic oxide (Bi ₂ O ₃ ), and 0.1 to 0.3 parts by weight of lubricant. Mixing uniformly; Grinding the mixed raw materials to form powder; Spray drying the pulverized powder to form granular powder; Molding the granular powder to form a molded body; Sintering the molded body to form a sintered body; And The method of producing an electromagnetic wave absorber composition comprising the step of cooling the sintered body. Powder raw material composed of 55 to 65 parts by weight of iron oxide (Fe ₂ O ₃ ), 15 to 20 parts by weight of nickel oxide (NiO), 10 to 15 parts by weight of zinc oxide (ZnO), and 8 to 12 parts by weight of copper oxide (CuO); 45 to 65 parts by weight of the ceramic composition comprising 30 to 50 parts by weight of water, 0.2 to 0.6 parts by weight of dispersant, 0.5 to 1.0 part by weight of plasticizer, and 0.1 to 0.4 part by weight of lubricant; And 8 to 12 parts by weight of an acrylic resin, 20 to 40 parts by weight of a solvent, and 3 to 8 parts by weight of an additive with respect to the ceramic composition. The coating composition for absorbing electromagnetic waves according to claim 6, wherein the solvent comprises 50 to 90 parts by weight of a true solvent and 10 to 50 parts by weight of a diluent. The coating composition for absorbing electromagnetic waves according to claim 7, wherein the true solvent comprises 20 to 40 parts by weight of a ketone and 30 to 50 parts by weight of an ester. The coating composition for absorbing electromagnetic waves according to claim 7, wherein the diluent comprises 5 to 30 parts by weight of alcohol and 5 to 20 parts by weight of aliphatic hydrocarbon. Powder raw material composed of 55 to 65 parts by weight of iron oxide (Fe ₂ O ₃ ), 15 to 20 parts by weight of nickel oxide (NiO), 10 to 15 parts by weight of zinc oxide (ZnO), and 8 to 12 parts by weight of copper oxide (CuO); 30 to 50 parts by weight of water, 0.2 to 0.6 parts by weight of dispersant, 0.5 to 1.0 parts by weight of plasticizer, and 0.1 to 0.4 parts by weight of lubricant based on the powder raw material; Grinding the mixed raw materials to form a first powder; Spray drying the pulverized first powder to form granular powder; Sintering the granular powder to form a sintered body; Cooling the sintered body; Grinding the cooled sintered compact to form a second powder; And Method for producing a coating composition for absorbing electromagnetic waves, comprising the step of uniformly mixing the second powder and acrylic resin, a solvent, and an additive. The method of claim 10, wherein the mixed raw materials are pulverized to form the first powder by wet milling for 2 to 4 hours using a ball mill to obtain a first powder having a particle size of 1 to 3 탆. Method of producing a coating composition for absorbing electromagnetic waves, characterized in that the step of forming. The method of claim 10, wherein the step of spray drying the pulverized first powder to form granular powder, maintaining the inlet temperature of the spray dryer at 550 ~ 600 ℃, the outlet temperature of the spray dryer 100 ~ 150 ℃ The water content in the granular powder is maintained at 0. 1 to 0.4 parts by weight with respect to the granular powder, thereby producing a coating composition for absorbing electromagnetic waves. The method of claim 10, wherein the forming of the second powder, the electromagnetic wave absorption, characterized in that for grinding for 2 to 4 hours using a ball mill to form a second powder having a particle size of 5 to 15㎛ Method for producing a coating composition for use. The method of claim 10, wherein the forming of the sintered compact includes: i) loading the granular powder in a firing furnace and heating it to a temperature of 400 ° C. for 3 hours, ii) heating the temperature of the firing furnace at 400 ° C. for 1 hour. Maintaining, iii) heating the temperature of the kiln for 4 hours from 400 ° C. to 900 ° C., iii) maintaining the temperature of the kiln at 900 ° C. for 2 hours, iii) maintaining the temperature of the kiln Heating for 3 hours to reach 900 ° C to 1200 ° C, and iii) maintaining the temperature of the kiln for 2 hours at 1200 ° C. The method of claim 14, wherein the cooling of the sintered compact comprises: slow cooling the sintered compact loaded in the calcination furnace for 40 to 60 hours after closing the sintering furnace and the sintered compact loaded in the calcination furnace at a temperature of 200 ° C or less. Taking out the step of naturally cooling the sintered body further comprising the manufacturing method of the electromagnetic wave absorbing coating composition. The method of claim 10, wherein the step of uniformly mixing the second powder, acrylic resin, solvent, and additives to form a paint, 45 to 65 parts by weight of the second powder, 8 to acrylic resin relative to the second powder 12 weight part, 20-40 weight part of solvents, and 3-8 weight part of additives are mixed, The manufacturing method of the electromagnetic wave absorption coating composition characterized by the above-mentioned. A method for applying an electromagnetic wave absorbing coating composition according to claim 10, wherein the coating composition for absorbing electromagnetic waves is sprayed with a thickness of 15 to 40 µm on the inner wall or the outer wall of the case of the device for emitting electromagnetic waves. The coating method for electromagnetic wave absorbing coating composition according to claim 17, wherein the method for applying the electromagnetic wave absorbing coating composition is performed by using a spray gun having a diameter of 1.3 to 1.5 mm at a spray pressure of 3 to 5 kg / cm 2. Spraying the inner or outer walls of the case of the device for emitting electromagnetic waves, and drying the sprayed electromagnetic wave absorbing coating composition at a temperature of 30 to 40 ° C. for 10 to 15 minutes. Coating method of coating composition for electromagnetic wave absorption. 18. The method of claim 17, wherein the device for emitting electromagnetic waves is a wired or wireless communication device including a cellular phone, a pager, a wired or wireless telephone, or a radio. 18. The method of claim 17, wherein the device that emits electromagnetic waves comprises communication base station equipment and devices. 18. The method of claim 17, wherein the device for emitting electromagnetic waves comprises a broadcast equipment and a device. 18. The apparatus of claim 17, wherein the device that emits electromagnetic waves is a computer, television, microwave oven, hair dryer, electric shaver, electric blanket and blanket, humidifier, anion generator, vacuum cleaner, refrigerator, washing machine, fan, air conditioner, audio, electricity. A method of applying an electromagnetic wave absorbing coating composition, characterized in that it is an electric or electronic device including a massager, a massager, and a hearing aid. 18. The method of claim 17, wherein the device for emitting electromagnetic waves comprises a medical instrument and a device. 18. The method of applying a coating composition for absorbing electromagnetic waves according to claim 17, wherein the device for emitting electromagnetic waves includes office automation equipment and devices. 18. The method of applying a coating composition for absorbing electromagnetic waves according to claim 17, wherein the device for emitting electromagnetic waves includes a control device for rotation and distribution. 18. The electromagnetic wave device according to claim 17, wherein the device for emitting electromagnetic waves is an electric wiring device including a light fixture, a heating device, an outlet, an electrical material, a desk lamp, a power distribution device, a power distribution line, a power plant device, and a transformer. Application method of the coating composition for absorption. 18. The method of applying a coating composition for absorbing electromagnetic waves according to claim 17, wherein the device for emitting electromagnetic waves comprises a motor. 18. The method of applying a coating composition for absorbing electromagnetic waves according to claim 17, wherein the device for emitting electromagnetic waves includes a measuring device using electric electrons. 18. The method of applying a coating composition for absorbing electromagnetic waves according to claim 17, wherein the device for emitting electromagnetic waves is an automobile or parts thereof including a car stereo, wiring, and connector of the automobile. A method for applying an electromagnetic wave absorbing coating composition according to claim 10, wherein the coating composition for absorbing electromagnetic waves is used for shielding a measurement shielding chamber. The coating method for electromagnetic wave absorbing coating composition according to claim 10, wherein the coating composition for electromagnetic wave absorbing is spray-coated to clothes and accessories with a thickness of 15 to 40 µm. A method for applying an electromagnetic wave absorbing coating composition according to claim 10, wherein the coating composition for absorbing electromagnetic waves is spray-coated to a shielding cable such as a communication line and a distribution line. A method for applying an electromagnetic wave absorbing coating composition according to claim 10, wherein the coating composition for electromagnetic wave absorbing is applied to a shielding cable such as a communication line and a transmission and distribution line by powder extrusion. A method for applying an electromagnetic wave absorbing coating composition according to claim 10, wherein the coating composition for absorbing electromagnetic waves is spray-coated to a building material such as wallpaper, paint, or tile at a thickness of 15 to 40 µm. A method for applying an electromagnetic wave absorbing coating composition according to claim 10, wherein the coating composition for absorbing electromagnetic waves is applied to a building material such as wallpaper, paint, or tile by powder injection. A device for emitting electromagnetic waves, characterized in that the coating composition for absorbing electromagnetic waves according to claim 10 is applied to an inner wall or an outer wall of the housing to reduce electromagnetic waves. 37. The device of claim 36, wherein the device for emitting electromagnetic waves coated with the electromagnetic wave absorbing coating composition is a wired or wireless communication device including a cellular phone, a pager, a wired or wireless telephone, and a radio. 37. The device of claim 36, wherein the device for emitting electromagnetic waves coated with the electromagnetic wave absorbing coating composition comprises communication base station equipment and equipment. The apparatus for emitting electromagnetic waves coated with the electromagnetic wave absorbing coating composition is a computer, a television, a microwave oven, a hair dryer, an electric shaver, an electric blanket and a blanket, a humidifier, an anion generator, a vacuum cleaner, a refrigerator and a washing machine. And electrical and electronic devices, including electric fans, air conditioners, audio, electric massagers and massagers, and hearing aids. 37. The apparatus of claim 36, wherein the device for emitting electromagnetic waves coated with the electromagnetic wave absorbing coating composition comprises medical devices and devices, office automation devices and devices, control devices for rotation or distribution, and light fixtures, heating devices, electrical outlets, electrical outlets, and electric appliances. An apparatus for emitting electromagnetic waves, characterized in that it is an electrical wiring apparatus comprising a material, a desk lamp, a distribution apparatus, a power distribution line, a power plant apparatus and a transformer. 37. The device of claim 36, wherein the device for emitting electromagnetic waves coated with the electromagnetic wave absorbing coating composition comprises a motor and a measuring device using electrical and electronic equipment. 37. The device of claim 36, wherein the device for emitting electromagnetic waves coated with the electromagnetic wave absorbing coating composition is a car or parts thereof including a car stereo, a wiring, and a connector of the automobile.