KR100804438B1 - Conductive sheet with high density and the process of producing the same - Google Patents

Abstract

A conductive sheet with a high density and a method for producing the same are provided to be used as a gasket sheet for shielding electromagnetic waves having high density elastic power, impact absorption, and adhesion. A conductive sheet(100) with a high density comprises a high density anti-static sheet(20) and a conductive layer. The high density anti-static sheet has a density of 100~600 kg/m3. The conductive layer is formed on at least one surface of the high density anti-static sheet. The high density anti-static sheet is manufactured by compressing an anti-static foam(10) at a volume of 0.5~0.1 times as large as an initial volume of the anti-static foam manufactured by foaming and hardening a foaming liquid material including polyol, isocynate, and an ion complex type charger in a mold.

Description

Conductive Sheet with High Density and the process of producing the same

1 is a process chart showing a manufacturing method of a high-density conductive sheet according to an embodiment of the present invention.

* Description of the Drawing Symbols *

10: Chargeable foam containing ion complex type charging agent

20: high density electrostatic sheet

30: conductive layer

100: high density conductive sheet

The present invention relates to a high-density conductive sheet and a method of manufacturing the same, and more particularly, to a high-density chargeable sheet having a microcell structure that maximizes conductivity by compression molding a high-density antistatic high density foam and at least one of the high-density chargeable sheets. The present invention relates to a high-density conductive sheet capable of vertically conducting electricity including a conductive layer formed on one surface thereof, and a manufacturing method thereof.

Various electronic devices that appeared with the development of the industry have a complicated circuit configuration to have a variety of functions in accordance with the needs of consumers seeking more functions, speed, portability, etc. Especially, portable electronic devices such as mobile communication terminals The trend is to produce smaller sizes.

When the electronic devices are high performance and miniaturized, many circuits are inevitably integrated in a narrow space, and the circuits are affected by radio noise, that is, electromagnetic waves, and are likely to cause mechanical malfunction or product quality degradation. In addition, it is well known that when electromagnetic waves leak outside of electronic devices, they adversely affect the function of the human body. Therefore, it imparts conductivity to gaskets interposed to shield electromagnetic waves and static electricity generated from seams or opening doors of electronic devices, or it imparts conductivity to liquid crystal screen cushions that support LCD screens of digital devices. It shields electromagnetic waves and static electricity. In addition, the electromagnetic wave shielding agent is attached to the path through which radio waves are emitted to block electromagnetic waves.

Electromagnetic shielding shock-absorbing gaskets used in displays, mobile communications, and battery electronics must be fully closed and tightly shielded in tight spaces while simultaneously shielding electromagnetic waves from inside and outside the device. The surface of the impact preventing gasket having the electromagnetic shielding function must not only have electrical conductivity, but also have a good conductivity in the vertical direction of the gasket sheet.

In this regard, the conventional electromagnetic shielding gasket is a flexible conductive conductive material such as gold, silver, copper, nickel, aluminum, or the like wrapped with an adhesive on the upper and lower surfaces of the flexible foam sheet, or the foam in a mold containing the conductive fabric Adhesive molding by individual or continuous injection followed by die cutting to the required size and shape (US Pat. No. 5,028,739). Gaskets manufactured according to the prior art as described above are hard, stretchy and non-adhesive conductive fabrics are adhesively wrapped on both upper and lower sides of the polyurethane foam, and thus there is a problem of impairing shock absorption or vibration blocking.

In addition, Korean Patent Application No. 10-2003-0100112 discloses that a polymer elastomer sheet is cast laminated on one side of a polyester base film, and a conductive material layer is laminated on the other side of the base film. A gasket sheet manufacturing method is disclosed, which is formed by forming a through hole to penetrate the upper and lower portions, and coating a conductive paint layer on the upper elastic sheet surface of the laminate sheet and the inner wall of the punch. However, this also has the disadvantages of productivity and workability, such as the burden of the secondary post-processing process to form a through hole to penetrate the upper and lower parts.

Accordingly, the present inventors have intensively attempted to develop a high-density conductive sheet having excellent current conduction ability in the up, down, left, and right sides without adding an additional process after the manufacture of the sheet.

After all, an object of the present invention is to provide a high-density conductive sheet of a microcell structure through a foam compression process capable of energizing up and down without a separate punch.

Still another object of the present invention is to provide a method of manufacturing a high-density conductive sheet capable of vertically energizing without a separate drilling step.

The present invention to achieve the above object

It provides a high density antistatic sheet having a density of 100 ~ 600kg / m ³ and a conductive layer on at least one side of the high density antistatic sheet.

The high-density antistatic sheet compresses the antistatic foam prepared by foaming and curing the foam liquid raw material for preparing the foam containing polyol, isocyanate and ion complex type charging agent in a mold to a volume of 0.5 to 0.1 times the initial volume. Can be prepared.

The foam may further comprise one or more of a reactive silicone foam stabilizer, a catalyst, a pigment, and a foaming agent.

The foamed liquid is 50 to 80% by weight of polyol, 10 to 30% by weight of isocyanate, 0.1 to 2% by weight of reaction catalyst, 0.5 to 3% by weight of reactive silicone foam stabilizer, 0.5 to 3% by weight of pigment, 0.1 to 1.0% by weight of blowing agent, organic ions It may be made of 0.25 to 32% by weight of the complex-type charging agent.

The conductive layer may be formed by coating and drying the conductive coating solution on the surface of the high-density antistatic sheet using a coating method such as gravure, roll, printing, casting, spray, screen printing, or the like.

The conductive coating solution has a conductive spherical shape or flake shape with respect to a highly elastic crosslinkable or non-crosslinkable synthetic resin such as an acrylic resin, a urethane resin, a silicone resin, a silicon fluoride resin, a polyester, an epoxy resin, or a copolymer resin thereof, which is a general thermosetting binder resin. It can be used by adding the powder of 50 to 80% by weight. The conductive powder may be at least one selected from metals such as gold, silver, copper, nickel, silver coated copper, aluminum, and carbon, graphite, and conductive polymers.

For another object of the present invention

Preparing a foaming liquid which is a raw material of polyurethane foaming comprising an ion complex conductive material, a polyol and an isocyanate; Preparing a foam by injecting the foam into a mold to foam and react with the foam; Manufacturing a high-density antistatic sheet for energizing the foam by compressing the foam to a volume of 0.5 to 0.1 times the initial volume by 150 to 200 ° C. for 1 to 5 minutes after peeling the foaming process. It provides a method for producing a high-density conductive sheet comprising the step of coating and drying the conductive coating solution on at least one surface of the high-density antistatic sheet to form a conductive layer.

1 is a process diagram showing a method for manufacturing a high density conductive sheet according to the present invention. As can be seen in Figure 1, in the present invention, the foam liquid raw material for preparing foam foam containing polyol, isocyanate and ionic complex type charging agent is foamed and cured in a mold to produce an antistatic foam 10, and After the foamed foam is subjected to peeling and compression processing to produce a high-density antistatic sheet 20, the conductive coating solution is coated on the antistatic sheet to form a conductive layer 3 to form a high density conductive sheet 100. Get

In order to obtain a general antistatic polyurethane foam block, a low density foam is formed because it is generally foamed in a slabstock type continuous polyurethane block production method and then sliced and processed into a sheet having a necessary thickness. There is no skin layer, and the adhesion is poor, and a high density foam cannot be obtained.

On the other hand, in the present invention, a polyol, an isocyanate and an ion-complex type charging agent, a foam stabilizer, a catalyst, and the like are mixed as a main raw material to prepare a foam material for polyurethane foam, and the raw material is foamed and cured in a cylindrical mold. After the foam is peeled to 0.9 ~ 5.0mm thickness. The exfoliated foam sheet may be thermally compressed by an automatic compression device to obtain a high-density chargeable sheet capable of fine control while having a thin film thickness of 0.2 to 2 mm.

In the case of a low-density elastic foam, the surface becomes rough, but the high-density electrified compressed sheet according to the present invention forms a constant skin layer by thermal compression, so that no separate surface treatment step is necessary.

That is, the antistatic foam prepared according to the present invention is cut in a continuous roll form to a thickness of 0.9 ~ 5 mm through a peeling cutting machine, and then 150 ~ 200 ℃, continuous compression for 1 to 5 minutes to a high density of the desired thickness An antistatic polyurethane sheet can be produced. The surface resistance of the high-density polyurethane sheet according to the present invention and the resistance of up and down current were measured in accordance with ASTM D257, which ranges from 105 kW / sq to 1010 kW / sq.

In the present invention, the antistatic foam may be prepared by using a polyurethane foam mainly composed of polyol and isocyanate. The polyurethane foam is 50 to 80% by weight of polyol, 10 to 30% by weight of isocyanate, 0.1 to 2% by weight of catalyst, 0.5 to 3% by weight of reactive silicone foam stabilizer, 0.5 to 3% by weight of pigment, 0.1 to 1.0% by weight of blowing agent, The foam raw material containing 0.25-32 weight% of ion complex type charging agents can be manufactured by foaming and hardening in a mold.

At this time, the addition amount of the ion-complex type charging agent is adjusted so as to have an appropriate resistance value according to the kind of the material to impart conductivity, and is generally 0.5 to 40 parts by weight, preferably 5 to 20 parts based on 100 parts by weight of the polyol component. It is set in the weight part range. If the addition amount is less than 0.5 parts by weight, the antistatic effect is insufficient, the surface resistance may exceed 1010Ω / cm, and if the addition amount is more than 40 parts by weight, the surface resistance is improved, while the brittleness of the chargeable foam This is because there is a possibility that physical problems such as deterioration may occur, and manufacturing cost increases.

In the present invention, the polyol constituting the polyurethane raw material is a polyether polyol, polyester polyol, polytetramethylene ether glycol, THF-alkylene oxide (alkylene oxide) Polyols selected from the group consisting of copolymer polyols, acrylic polyols and polyolefin polyols may be used.

In the present invention, the isocyanate (isocynate) may use a polyisocyanate type of at least two functional groups, toluene diisocynate (TDI), ortho toluidine diisocynate (TODI), naphthalene diisocyanate (naphthalene diisocynate: NDI), a group consisting of aromatic isocyanates such as xylene diisocynate (XDI), methylene diphenyl diisocynate (MDI) and carbodiimide modified MDI, aliphatic isocyanates, substituted isocyanates and derivatives thereof Isocyanates selected from can be used.

In the present invention, the ion complex type charging agent is a chemical structure of an ion-complex, and is a cation-ion conductive material formed by coordination bonding of at least one selected from alkali metal salts, alkaline earth metal salts and transition metal salts with an ion conductive organic compound. It is an anion-ion conductor. More specifically, an alkali metal cation or a transition metal cation is used as the conductive cation-ion conductive material, and elements such as oxygen, nitrogen, sulfur, and phosphorus in the molecule capable of forming a ligand for coordination with them are included. And a cation conducting organic compound having a boiling point of 140 ° C. or higher.

Examples of such cationic conducting organic compounds include carbonate, ketone, sulfone, amide, ether, polyol, nitrile and nitrite. ), An organic compound having a group selected from the group consisting of phosphonate and acetate. More specifically, propylene carbonate (PC), propanediol cyclic carbonate, hydroxybutyric acid lactone, acetonitrile, diphenyl ether, dimethyl formamide (DMF), N-methylacetamide (NMAA), N, N -Dimethylacetamide (DMA), N-methylpropionamide (NMPA), N-methylpyrrolidone (NMP), sulfinylbismethane and the like can be used together with ethylene glycol (EG), diethylene glycol Polyols and the like can be used, and when using them, they can be used alone or as a mixture. In particular, among them, EG, DMF, DMA, PC, NMP and the like most easily form various types of coordination bonds with the cations of the metal salts according to the present invention.

In addition, the conductive anion-ion conductive material is a counter anion of an alkali metal salt, a counter anion of a transition metal salt, and anionic conductive organic compounds having a boiling point of 140 ° C. or higher having an electron accepting function in the molecule are used to bond them. That is, compounds having a group selected from the group consisting of sulfoxide, ester, sulfate, phosphate, phosphite and imide are used. More specifically trilauryl phosphite, dipropylene glycol phosphite, poly dipropylene glycol phosphate, tris chloroethyl ester phosphate, triisodecyl phosphite, dichloropropanol phosphate, diphenylhydrogen phosphate, tris chloromethyl ester and One or a mixture of two or more selected from the group consisting of dimethyl sulfoxide (DMSO) is used. The reason why the boiling point is 140 ° C. or higher is that when the antistatic agent prepared by using the boiling point below 140 ° C. is added to the polymer resin, the antistatic effect due to the molecular weight decrease during thermoforming, the physical properties of the molded product, etc. It is caused.

Metal salts used in the present invention include alkali metal salts, that is, salts such as lithium, sodium, potassium, and alkaline earth metal salts, such as magnesium, calcium, and the like, specifically, LiPF ₆ , LiBF ₄ , LiSbF ₆ , LiClO ₄ , LiCF ₃ SO ₃ , LiAsF ₆ , LiC (CF ₃ SO ₃ ) ₃ , LiN (CF ₃ SO ₃ ) ₂ , LiI, LiBr, LiCl, LiF, NaPF ₆ , NaClO ₄ , NaI, NaSCN, KSCN, KPF ₆ , and KClO ₄ It may be selected from the group consisting of. In addition, a transition metal salt may be used. As the transition metal salt, all metal salts including Fe, Ni, Cu, Zn, etc., more specifically FeCl ₃ , FeCl ₂ , FeBr ₃ , FeBr ₂ , FeI ₂ , FeI ₃ , Fe (CH ₃ COO) ₃ , Fe (SCN) ₃ , CuCl, CuBr, CuI, CuCN, CuCl ₂ , CuBr ₂ , CuI ₂ , Cu (NO ₃ ) ₂ , Cu (CH ₃ COO) ₂ , Cu (SCN) ₂ A single or a mixture selected from the group consisting of ZnCl ₂ , ZnBr ₂ , ZnI ₂ , and Zn (CH ₃ COO) ₃ can be used.

The use amount of the ion complex type charging agent is preferably 0.25 to 32% by weight of the total foam liquid raw material, and most preferably 20 to 30% by weight. If the amount is less than 0.25% by weight, the electrical conductivity is low, it does not have an antistatic function, and when it is used more than 32% by weight, it causes a change in physical properties.

The ion complex type charging agent may be prepared by the following method. The metal salt is first placed in a cationic conducting organic compound and heated with vigorous stirring to form a coordination compound. The reaction time is from 1 hour to 24 hours. Upon completion of the reaction, anion conducting organic compounds are added to the reaction product and heated with vigorous stirring for an additional 1 hour to 24 hours. The coordination reaction is then completed under reduced pressure in vacuo to give the final solution. After the reaction mixture has cooled to room temperature, an unreacted metal salt is removed using a filter.

The ion complex type charging agent solution can form additional secondary coordination bonds with the polyether or polyester functional groups of the urethane polymer chain, thereby exhibiting more uniform and stable antistatic performance.

In the present invention, the conductive coating liquid on the high-density antistatic sheet is at least selected from metals such as copper, aluminum, carbon, graphite, and conductive polymers coated with at least one selected from the group consisting of gold, silver, copper, nickel and silver. Used as a spherical or flake structure), crosslinking properties excellent in elasticity such as acrylic resins, urethane resins, silicone resins, silicon fluoride resins, polyesters, epoxy resins or copolymers thereof, which are common thermosetting binder resins. Or it is prepared by adding 50 to 80% by weight to the non-crosslinked synthetic resin. Conductive spherical or flake powders used in the conductive coating liquids are those having a particle size in the range of 0.5-50 microns. The conductive coating solution thus prepared is coated on at least one side or both sides of the high-density antistatic sheet by using a coating method such as gravure, roll, printing, casting, spray, screen printing, and the like. It is possible to produce a high-density conductive sheet having high density, high elasticity, excellent shock absorption, and adhesiveness while having excellent electrical conductivity of up, down, left, and right without a secondary additional process.

Reaction catalysts that can be used in the present invention include, for example, triethylamine, diethanolamine, N, N, N ', N'-tetramethylhexanediamine, triethylenediamine, N-methylmorpholine, dimethylaminoethanol, and the like. And organometallic catalysts such as amine catalyst, dibutyl tin dilaurate, dibutyl tin diacetate, stanas octoate, dibutyl tin mercaptide and tin octenate. Among these catalysts, the amine catalyst is indispensable and an organometallic catalyst may be added if necessary.

Reactive silicone foam stabilizers that can be used in the present invention include polyether silicone oils, nonionic surfactants, ionic surfactants, and the like, which may be used alone or in combination of two or more thereof.

As the foaming agent that can be used in the present invention, the main foaming agent uses water, and as the auxiliary foaming agent, low boiling point organic foaming agents such as methylene chloride and cyclopentane can be used as necessary.

The high-density conductive sheet according to the present invention has a top and bottom left and right by the salt bridge effect by the additive-resistant high-density electrifying sheet without a secondary additional process such as a through hole process to penetrate the upper and lower parts to complement conductivity. It is possible to manufacture a conductive sheet excellent in the electrical conductivity. The surface resistance and the vertical conduction resistance of the high density conductive sheet according to the present invention have 0.1 kPa / sq or less.

Through the following examples will be described the present invention in more detail. These examples are only for illustrating the present invention, and the scope of the present invention will not be construed as being limited by these examples.

Example  One

Polyol, the main raw material (polyether polyol having a molecular weight of 4,00 to 6,000 and ethylene glycol (EO) content in the structure of 10 to 30%) 66.5 wt%, polyisocyanate (M-MDI, NCO content: 28%) 19.2 wt% %, 1.4 wt% crosslinking agent (1,4-butanol), 0.1 wt% amine catalyst (triethylamine), 1.3 wt% foam stabilizer (silicone-based material), ion complex type charging agent (SR 6005, Nano Chem Tech. Co., KOREA) 10% by weight, pigment 1 part by weight, foaming material (H ₂ O) 0.5% by weight of the polyurethane foam was prepared to prepare an antistatic foam by foaming reaction and curing in a cylindrical mold.

After peeling (peeling) the prepared anti-foam foam to a thickness of 2.0 mm and heat-compressed for 2 minutes at a temperature of 180 ℃ in an automatic compression device to prepare a high-density antistatic sheet having excellent up-down conduction sheet having a thickness of 0.3 mm thin film. . The surface resistance of the prepared high-density antistatic sheet showed 2 x 10E5 kW / sq by ASTM D257 method, and the upper and lower conduction resistances also showed 3 x 10E5 kW.

The conductive coating liquid (silver flake 60% by weight, urethane resin 40% by weight) was coated on the prepared high-density antistatic sheet by a roll coating method to provide excellent up-and-down conduction having a surface resistance of 0.03 s / sq and a vertical conduction resistance of 0.04 Ω. A high density conductive sheet was produced.

Example  2-3

In the polyurethane foam prepared in the same manner as in Example 1, 5 wt% (Example 2) and 15 wt% (Example 3) of the ion complex type charging agent (SR 6005, Nano Chem Tech. Co., KOREA) A high density conductive sheet having excellent up and down energization was prepared in the same manner except for the addition.

Example  4-5

The antistatic foam prepared in the same manner as in Example 1 was peeled to 4.0 mm thickness (Example 4) and 8 mm thickness (Example 5), and then thermally compressed in an automatic compression device to have a thickness of 0.3 mm thin film. Except that a high-density antistatic sheet was prepared, a high-density conductive sheet having excellent upper and lower conductance was similarly manufactured.

Comparative example  One

A high-density conductive sheet was produced in the same manner as in Example 1 except that an insulator high-density foam was not added to the polyurethane foam prepared in the same manner as in Example 1.

Comparative example  2

Except for producing an insulator high density foam that does not add an ion complex type charging agent to the polyurethane foam prepared in the same manner as in Example 1, a high density conductive sheet was prepared in the same manner, and then penetrated the upper and lower portions for vertical conduction. The high-density conductive sheet | seat was manufactured by making the perforation (0.5 mm in diameter and 1.5 mm of distance from an adjacent hole).

Comparative example  3

A conductive sheet was prepared in the same manner as in Example 1, except that the antistatic sheet was prepared by peeling the polyurethane foam prepared in the same manner as in Example 1 to have a thickness of 0.3 mm thin film without high temperature compression.

Table 1 shows the physical properties of the conductive sheets prepared in Examples 1 to 5 and Comparative Examples 1 to 3.

Comparison of Properties of High Density Conductive Sheets

Example 1 Example 2 Example 3 Example 4 Example 5 Comparative Example 1 Comparative Example 2 Comparative Example 3 Surface resistance (Ω / sq) 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.04 Top and bottom conduction resistance 0.04 0.06 0.03 0.04 0.03 10E11 0.06 0.08 Electromagnetic shielding efficiency (dB, 0.01 ~ 1GHz) 96 94 98 96 98 89 89 89

As shown in Table 1, the high-density conductive sheet manufactured according to the present invention penetrates the upper and lower portions by the salt bridge effect by the internal high-density high-charging sheet without the need for a secondary additional process such as a through hole penetrating the upper and lower portions. Compared with the perforated sheet, the high density conductive sheet having similar or somewhat better physical properties could be produced.

Example  6

50 wt% conductive polymer coating liquid [conductive polymer (Baytron PH, Bayer Co.), 20 wt% water-soluble urethane resin, 10 wt% n-methyl-2-pyrrolidinone to the high-density antistatic sheet prepared in the same manner as in Example 1 %, Isopropyl alcohol 20% by weight] was coated by a roll coating method to prepare a high-density conductive sheet having excellent up-down conduction resistance having a surface resistance of 2 x 10E4 dl / sq and a vertical conduction resistance of 3 x 10E4 dl.

As described in detail above, according to the present invention, it is not only excellent in up, down, left, and right conduction without undergoing a second additional process such as through holes penetrating the upper and lower parts, and also has a constant skin layer on the surface without a separate surface treatment. It is possible to provide a high density conductive sheet which can be formed. In addition, the high-density conductive sheet manufactured according to the present invention is excellent in high-density elastic force, shock absorption and adhesion can be applied to various applications such as a gasket sheet for electromagnetic shielding for application to display devices, mobile communication devices, electrical and electronic products.

Claims (11)

delete A high density antistatic sheet having a density of 100 to 600 kg / m ³ and a conductive layer on at least one surface of the high density antistatic sheet,  The high-density antistatic sheet is foamed and cured the foaming material raw material for preparing the foam containing polyol, isocyanate and ion complex type charging agent in a mold to compress the antistatic foam prepared by the volume of 0.5 ~ 0.1 times the initial volume The high density conductive sheet which is produced. The high density conductive sheet according to claim 2, wherein the ion-complex type charging agent is contained in an amount of 0.5 to 40 parts by weight based on 100 parts by weight of the polyol component. The method according to claim 2, wherein the foam is 50 to 80% by weight of polyol, 10 to 30% by weight of isocyanate, 0.1 to 2% by weight of reaction catalyst, 0.5 to 3% by weight of reactive silicone foam stabilizer 0.5 to 3% by weight of pigment, and 0.1 to 0.1% of foaming agent. 1.0 weight%, 0.25-32 weight% of organic ion complex type charging agents, The high-density electroconductive sheet characterized by the above-mentioned. The method of claim 2, wherein the conductive layer is formed by coating and drying a conductive coating solution on the surface of the high-density antistatic sheet using a coating method such as gravure, roll, printing, casting, spraying, screen printing, and the like. Conductive spherical or flake type powders are used for crosslinkable or non-crosslinkable synthetic resins having excellent elasticity, such as acrylic resins, urethane resins, silicone resins, silicon fluoride resins, polyesters, epoxy resins, or copolymerized resins, which are general thermosetting binder resins. A high density conductive sheet, which is prepared by adding 50 to 80% by weight. The high-density conductive sheet according to claim 5, wherein the conductive powder is at least one selected from gold, silver, copper, nickel, silver coated copper, aluminum, carbon, graphite, and a conductive polymer, or a mixture thereof. . The method of claim 2, wherein the polyol is a polyether polyol, polyester polyol, polytetramethylene ether glycol, THF-alkylene oxide copolymer polyol, acrylic A high density conductive sheet, characterized in that one or two or more polyols selected from the group consisting of polyols (acryl polyol) and polyolefin polyol (polyolefin polyol). According to claim 2, wherein the isocyanate (isocynate) is toluene diisocynate (TDI), ortho toluidine diisocynate (TODI), naphthalene diisocynate (NDI), xylene diisocyanate (xylene) at least two functional groups selected from the group consisting of aromatic isocyanates, aliphatic isocyanates, substituted isocyanates and derivatives thereof such as diisocynate: XDI), methylene diphenyl diisocynate (MDI) and carbodiimide-modified MDI Isocyanate having high density conductive sheet characterized by the above-mentioned. 3. The cation-ion conductive material according to claim 2, wherein the ion complex type charging agent is a chemical structure of an ion-complex, and is formed by coordinating an at least one selected from alkali metal salts, alkaline earth metal salts and transition metal salts with an ion conductive organic compound. Or an anion-ion conductive material. Preparing a foaming liquid which is a raw material of polyurethane foaming comprising an ionic complex type conductive agent, a polyol and an isocyanate; Preparing a foam by injecting the foam into a mold to foam and react with the foam; Manufacturing a high-density antistatic sheet having a top and bottom energization by compressing the foam to a volume of 0.5 to 0.1 times by compressing the foam to 150 to 200 ° C. for 1 to 5 minutes after peeling processing; And applying and drying a conductive coating solution on at least one surface of the high density antistatic sheet to form a conductive layer. The method of claim 10, wherein the filling of the foam is a step of filling the foam with a thickness of 0.9 to 5.0 mm.

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