KR101956538B1 - Isotropic conductive foam using porous polyurethane foam and manufacturing method thereof - Google Patents

Abstract

The present invention relates to an isotropic conductive foam using a porous polyurethane, and more particularly, to a polyurethane foam comprising an open cell and a closed cell, which is superior in shock absorbing and restoring force to a conventional conductive foam , An isotropic conductive foam using a porous polyurethane foam having uniform electrical conductivity and a remarkably improved electromagnetic wave shielding efficiency, and a manufacturing method thereof.

Description

TECHNICAL FIELD [0001] The present invention relates to an isotropic conductive foam using a porous polyurethane foam, and an isotropic conductive foam using the porous polyurethane foam,

The present invention relates to an isotropic conductive foam using a porous polyurethane, and more particularly to a porous polyurethane foam which is superior in shock absorbing power and restoring force to a conventional conductive foam and has a uniform electric conductivity, The present invention relates to an isotropic conductive foam using a porous polyurethane foam having a remarkably improved efficiency and a method for producing the same.

Conductive foam is used in various electronic products. It is used for mobile terminals such as smart phones and tablets, digital TVs such as LED TVs and OLED TVs, fixing parts for flexible displays, improving adhesion with adhered materials, shock absorption, electrostatic discharge (ESD), thermal diffusion, electromagnetic shielding, and grounding.

A conventional conductive foam is a urethane foam having a sponge structure having microcells. In general, when the compression is performed at a constant level during the compression, %, Which is known to be very poor.

In addition, in the case of the foam and fabric bonding products which have been used in the prior art, not only the appearance of the product is deteriorated due to the burr of the cutting face at the time of die-cutting, Causing a problem that results in a short circuit of the product. These problems lead to shortening of the service life of the product and deterioration of performance. In addition, the product is not restored to its original shape during reassembly after detachment due to repair of the product, and expensive accessories often need to be replaced.

The demand for improvement of these problems has been going on for a long time, but it is difficult to expect the improvement of the structural restoration rate due to the large pore structure, low density, and poor mechanical strength in the existing products which are plated on the foam of the existing microcell sponge structure . Therefore, in order to solve such a problem, it is necessary to change the structure of the foam itself, and accordingly, it is expected that the production technology and the plating technology of the foam should be developed together.

KR 10-1175346 KR 10-0705973

An object of the present invention is to provide an isotropic conductive foam using a porous polyurethane foam having uniform electrical conductivity and remarkably improved electromagnetic wave shielding efficiency by using a porous polyurethane foam having much better shock absorbing power and restoring force, and a method for producing the same.

It is another object of the present invention to provide a function of safely protecting constituent parts from impact by attaching an up-down energizing function and an improved impact absorbing power by a porous polyurethane foam including both an open cell and a closed cell.

Another object of the present invention is to satisfy the demand for miniaturization and weight reduction of a product by using a porous polyurethane foam.

In addition, in the case of the foam and the fabric-bonded product of the prior art, the conductive foam of the present invention damages the appearance of the product due to the burr of the cut surface at the time of die-cutting, It is another object of the present invention to provide a method for manufacturing a conductive foam which can solve the problem of causing a short circuit of a product and which can be manufactured to a desired thickness without breaking the pore structure even when cut.

The isotropic conductive foam using the porous polyurethane foam according to the present invention is a polyurethane foam formed by mixing an open cell and a closed cell, a bonding adhesive coated on the lower part of the polyurethane foam, a plurality of through holes And a conductive adhesive layer formed on one side of at least one of the fabric layer and the skin layer. The conductive adhesive layer is formed on at least one surface of the fabric layer and the skin layer. And a release paper for protecting the adhesive surface of the electrically conductive pressure sensitive adhesive layer.

At least one of the polyurethane foam, the fabric layer and the skin layer constituting the isotropic conductive foam may be impregnated with a plating solution to form a plating layer on the surface.

The fabric layer may be replaced with a thin film including at least one selected from the group consisting of aluminum, gold, silver, copper, nickel, and carbon nanotubes.

The polyurethane foam and the fabric layer are characterized by being plated with an electrolytic or electroless plating solution to be conductive.

The plating solution may include at least one selected from the group consisting of copper, nickel, gold, silver, tin, aluminum, stainless steel, and cobalt.

The conductive adhesive layer may include at least one selected from the group consisting of acrylic, urethane, silicone, and synthetic rubber.

The conductive adhesive layer may include at least one selected from the group consisting of copper, nickel, silver, gold, tungsten, and aluminum.

A method for producing an isotropic conductive foam using porous polyurethane foam according to the present invention comprises the steps of foaming polyurethane on the back surface of release paper to form a polyurethane foam so as to mix open cells and closed cells, Coating the adhesive layer with a fabric layer of a woven polyester fabric so that a plurality of through holes are formed in the bonding adhesive, removing the release layer and coating the skin layer, forming a plating solution to form a conductive isotropic layer And a step of laminating a conductive adhesive layer on the back surface of the isotropic conductive foam.

Forming a volume ratio of the closed cell and the open cell to 1: 0.1 to 3; and laminating the release paper after lamination of the conductive adhesive layer to protect the adhesive surface of the conductive adhesive layer.

The isotropic conductive foam using the porous polyurethane foam of the present invention is a thin film urethane foam superior in shock absorbing power and restoring force as compared with the conventional conductive foam, and has an excellent isotropic conductivity by imparting electrical conductivity to the porous foam.

In addition, the present invention is a method of filling a certain portion of an open cell with a plating solution by impregnating a plating solution containing a metal powder having an electric charge to form a porous foam of a vertically energized structure, There is a possible effect.

It is a microcellular conductive foam that has high isotropic electrical conductivity while maintaining excellent shock absorption and restitution of high density thin foams, thereby not only replacing the conductive foam of the conventional microcell sponge structure but also providing excellent shock absorption and heat conduction The heat diffusion function is excellent.

Further, the present invention has the effect of satisfying the demand for miniaturization and weight reduction of a product as a material capable of simultaneously implementing shock absorption, light shielding, and conductivity and diffusion.

1 is a cross-sectional view of an isotropic conductive foam using a porous polyurethane foam according to the present invention.
2 is a cross-sectional view of an isotropic conductive foam using a porous polyurethane foam according to another embodiment of the present invention.
3 is a view showing a method for producing an isotropic conductive foam using porous polyurethane foam according to the present invention.
4 is a view showing a method for producing an isotropic conductive foam using a porous polyurethane foam according to the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention, and how to accomplish them, will become apparent by reference to the embodiments described in detail below with reference to the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the invention to those skilled in the art. Is provided to fully convey the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims.

The terminology used herein is for the purpose of illustrating embodiments and is not intended to be limiting of the present invention. In the present specification, the singular form includes plural forms unless otherwise specified in the specification. Like reference numerals designate the same or functionally similar elements throughout the specification. Accordingly, although the same reference numerals or similar reference numerals are not mentioned or described in the drawings, they may be described with reference to other drawings. Further, even if the reference numerals are not shown, they can be described with reference to other drawings.

1 is a cross-sectional view of an isotropic conductive foam using a porous polyurethane foam according to the present invention. Referring to FIG. 1A, the conductive foam 100 of the present invention includes a polyurethane foam 110 formed to mix an open cell and a closed cell, a bonding adhesive 120 coated on the lower portion of the polyurethane foam, A fabric layer 130 woven to form a plurality of through holes adhered to the bonding adhesive, a conductive adhesive layer 140 formed on a lower portion of the fabric layer, a skin layer 150 formed on the polyurethane foam, And a release paper 160 for protecting the adhesive surface of the electrically conductive pressure sensitive adhesive layer.

The polyurethane foam 110 is formed by foaming a raw resin on a release paper, and the release paper serves to support the formation of the polyurethane foam. In addition, handling and workability of the polyurethane foam can be facilitated. The releasing paper is not limited to a PET film but may be a releasing agent such as fluorine, silicone and waxes to improve releasability on at least one surface selected from the group consisting of polyester, polyethylene, polypropylene, polyimide, paper, Can be used.

The porosity of the polyurethane foam 110 is formed by using an open cell and a closed cell. When the volume ratio of the open cells is increased, the electrical conductivity efficiency is increased. When the volume ratio of the closed cells is increased, Therefore, in consideration of this, the volume ratio of the closed cell and the open cell can be made to be 1: 0.1 to 3, preferably 1: 1 to 2. If the volume ratio of the open cells is less than 0.1, the electrical conductivity efficiency obtained by including the open cells is lowered. If the volume ratio of the open cells is 3 or more, it is difficult to expect an increase in the impact absorption effect to be obtained, have.

Since the conductive foam 100 according to the present invention has porosity, it imparts high impact resistance to the tape, has high restoring force after compression, and has high electrical conductivity efficiency. The material of the polyurethane foam 110 is not limited to polyurethane but may include at least one selected from the group consisting of silicone foam, acrylic foam and polyolefin foam. The thickness of the foam layer can be made to be 10 to 3000 탆, but preferably 50 to 800 탆 is more suitable. If it is less than 10 mu m, the impact resistance and the restoring force are lowered, and when it exceeds 3000 mu m, it is difficult to obtain a further increase in restoring force, and it is too thick to adhere to each other easily, resulting in economic loss.

The polyurethane foam 110 comprises 30 to 80 parts by weight, preferably 40 to 60 parts by weight, of a polyether polyol, 30 to 80 parts by weight, preferably 40 to 80 parts by weight, based on 100 parts by weight of the composition for foaming, To 60 parts by weight, and is prepared by mixing 5 to 10 parts by weight of a crosslinking agent, 1 to 3 parts by weight of a catalyst, 1 to 5 parts by weight of a foaming agent, 5 to 15 parts by weight of a curing agent and 1 to 5 parts by weight of a black pigment. Mixed and defoamed using a vacuum stirrer, and an inert gas such as air or nitrogen gas is added thereto at a ratio of 20 to 30 parts by volume based on 100 parts by volume of the composition, followed by mixing using an agitator. The mixture is foamed on a release paper through a foaming machine to produce a foam. When the nitrogen gas is supplied at 20 to 30% by volume based on the volume of the composition 100, the volume ratio of the open cells to the closed cell volume 1 can be made 1 to 2. When the nitrogen gas is increased, The volume ratio of the closed cell and the open cell is 1: 2 to 3, and when the volume is 10 to 20% by volume, the volume ratio of the closed cell and the open cell is 1: 0.1 to 1 at 30 to 40 volume% .

As the cross-linking agent, a glycol-based or amine-based cross-linking agent may be used. Specifically, the crosslinking agent is selected from the group consisting of ethylene glycol, diethylene glycol, triethylene glycol, dipropylene glycol, 1,4-butanediol, 1,6-hexanediol, pentaerythritol, diethanolamine, triethanolamine, ethylenediamine, Tetraamine, methyleneorthochloraniline, 4,4-diphenylmethanediamine, 2,6-dichloro-4,4-diphenylmethanediamine, 2,4-toluenediamine, 2,6-toluenediamine and the like can be used . The crosslinking agent is preferably contained in an amount of 5 to 10 parts by weight based on 100 parts by weight of the foaming composition. When the crosslinking agent is less than 5, the density of the polyurethane foam falls. When the crosslinking agent is more than 10, the density of the polyurethane foam increases, have.

The catalyst may be an amine-based urethane catalyst or a metal-based urethane catalyst. The amine-based urethane catalyst acts to prevent the harmful substances from being detected in the final foam by the amine component directly participating in the reaction. That is, in the case of the foam composition using the conventional amine catalyst, the amine component in the foam remained and organic chemical substances were detected. However, since the foaming composition of the present invention uses the reactive amine-based urethane catalyst, Friendly. The reactive amine-based urethane catalyst is preferably contained in an amount of 1 to 3 parts by weight based on 100 parts by weight of the composition for foaming. Outside this range, the catalytic reaction is delayed and the density of the polyurethane foam is too low or too high And quality deteriorates due to poor curing.

The foam stabilizer may use a silicone surfactant, which serves to maintain the molding state of the polyurethane foam well. In addition, the silicone foam stabilizer facilitates the mixing of raw materials, lowers the surface tension of the composition for foaming to increase bubble generation, and stabilizes the urethane cell membrane to prevent the breakdown of the urethane cell and the foam off. The silicone surfactant is preferably contained in an amount of 1 to 5 parts by weight based on 100 parts by weight of the composition for foaming. If the silicone surfactant is out of the range, it is difficult to maintain the molded state of the polyurethane foam and the urethane cell is broken due to bubble destabilization .

In addition, the polyurethane foam according to the present invention may further comprise a black pigment for light blocking effect. The black pigment may include at least one selected from the group consisting of carbon black, iron oxide, copper oxide, tin oxide, and mixtures thereof. By including the black pigment, it is possible to prevent the light from leaking from the display panel and to absorb the light from the outside, thereby enhancing the image quality of the display panel and having a shading effect that prevents the tacky surface from being seen.

The bonding adhesive 120 may be coated on the upper or lower surface of the polyurethane foam 110. The bonding adhesive 120 may be formed of one or more materials selected from the group consisting of acrylic, rubber, urethane, epoxy and acrylate, and bonding the polyurethane foam and the fabric layer through adhesion or adhesion. The thickness of the bonding adhesive 120 may be 1 to 50 탆, preferably 5 to 30 탆, depending on the adhesive properties.

The fabric layer 130 may be formed of polyester fibers and may serve as a supporting layer of the polyurethane foam 110. [ (Draw Textured Yarn (DTY), Producer Textured Yarn (PTY), Throwster's Textured Yarn (TTY), and the like. , Interlacing Textured Yarn (ITY), Air Textured Yarn (ATY), Micro Miracle Yan (M2) and Poly Trimethylene Terephthalate (PTT). .

The thickness of the yarn may be 0.01 to 1,000 denier, preferably 1 to 500 denier. The hole size formed by weaving is usually expressed by a mesh, and the mesh of the fabric layer of the conductive foam 100 according to the present invention is preferably 80 to 350 mesh. The thickness of the fabric layer can be from 1 to 3,000 mu m, more preferably from 10 to 150 mu m.

The fabric layer 130 may be replaced with a thin film including at least one selected from the group consisting of aluminum, gold, silver, copper, nickel, and carbon nanotubes instead of polyester fibers.

1 (a), the conductive adhesive layer 140 may be formed below the fabric layer 130 or may be formed on the skin layer 150 as shown in FIG. 1 (c) And can be made of an adhesive tape. The conductive adhesive layer 140 may include at least one selected from the group consisting of acrylic, urethane, silicone, and synthetic rubber. In addition to the above-described thermosetting adhesive, a photo-curing adhesive may be used as the adhesive, and a pressure-sensitive adhesive made of a mixture of acrylate or acrylate with rubber or other resin may be used.

Examples of the acrylic resin include acrylates such as methyl methacrylate, methyl acrylate, ethyl acrylate, butyl acrylate, hexyl acrylate, n-octyl acrylate, isooctyl acrylate, 2-ethylhexyl acrylate, isobornyl acrylate, Acrylic acid, acrylic acid, acrylamide, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxybutyl acrylate, methacrylic acid, itaconic acid, maleic acid and the like Or more, and preferably a polymer resin containing the above-mentioned 2-ethylhexyl acrylate monomer can be used.

When the polymer resin containing the 2-ethylhexyl acrylate monomer is used, the cohesive force of the pressure-sensitive adhesive layer is excellent and the excessive increase in the adhesion strength can be suppressed, so that the good adhesion to the display panel as well as various electronic devices, housings, metals, It is possible to form an adhesive layer excellent in adhesion, re-peeling property and reworkability.

The thickness of the conductive adhesive layer 140 may be 5 to 100 μm, preferably 20 to 50 μm. When the thickness is less than 5 탆, the structural strength is very low. On the other hand, when the thickness is more than 100 탆, the adhesive force is increased more than necessary, so that a great effect of the electric conductivity can not be expected. The pressure-sensitive adhesive composition for forming the conductive adhesive layer 140 may include, but is not limited to, 30 parts by weight of acrylic acid based on 100 parts by weight of the acrylic polymer containing 2-ethylhexyl acrylate monomer.

The conductive adhesive layer 140 may include at least one selected from the group consisting of nickel, copper, silver, gold, tungsten, and aluminum. The size of the metal powder is preferably from 10 to 150 mu m, and the size distribution of the metal particles can be used singly or in combination of monodisperse and polydisperse. The amount of the metal powder to be added may be 3 to 20 parts by weight based on 100 parts by weight of the pressure-sensitive adhesive resin, and 5 to 10 parts by weight is preferable in view of the adhesive property. If the amount of the metal powder is less than 3, it is difficult to obtain the electric conductivity. If the amount of the metal powder is more than 20, it is difficult to obtain the desired effect due to the aggregation of the powders.

The skin layer 150 may be formed on the polyurethane foam 110 as shown in FIG. 1 (a), and may be formed on both the upper and lower portions of the polyurethane foam 110 as shown in FIG. 1 (b) As shown in FIG. Referring to FIG. 1B, after the polyurethane foam 110 is formed on the release paper, the skin layer 150 may be formed on the back surface of the polyurethane foam 110 to improve workability. Then, the skin layer 150 may be coated on both sides of the polyurethane foam 110 by removing the release paper and coating the skin layer 150.

The skin layer 150 may be formed of UV coating or polyurethane (PU) or thermoplastic polyurethane (TPU). The UV coating layer is formed by applying UV paint and curing in a very short time by irradiating ultraviolet rays. The conductive foam 100 according to the present invention includes the skin layer 150, so that it is easy to work and has an effect of increasing surface strength and tensile force.

The release paper 160 is used for protecting the adhesive surface of the conductive adhesive layer 140 and is detached when used. A PET film may be used. However, the present invention is not limited to this, and it is possible to use a fluorine, silicon, or polyimide film for improving peelability from the adhesive layer on at least one surface selected from the group consisting of polyester, polyethylene, polypropylene, polyimide, paper, non- A coating agent such as a wax can be used.

The isotropic conductive foam of Fig. 1 may be impregnated into the plating solution to form a plating layer between at least one layer. The bonding layer 120 may be coated on the polyurethane foam 110 to form the fabric layer 130 and then the plating layer may be filled with the plating solution to deposit the plating solution into the layer. Alternatively, the polyurethane foam 110 and the fabric layer 130 may be respectively plated in a plating solution, and then plated using a bonding adhesive 120.

2 is a cross-sectional view of an isotropic conductive foam using a porous polyurethane foam according to another embodiment of the present invention. Referring to FIG. 2, the conductive foam according to another embodiment of the present invention may further include a fabric layer 130 and a conductive adhesive layer 140 on the polyurethane foam 110 to serve as a double-sided adhesive tape . A bonding adhesive 120 is formed on the polyurethane foam 110 and a fabric layer 130 is formed on the polyurethane foam 110 and then a conductive adhesive layer 140 is formed on the fabric layer 130, So that the grounding and energizing effect can be obtained.

3 is a view showing a method for producing an isotropic conductive foam using porous polyurethane foam according to the present invention. Referring to FIG. 3, a method of manufacturing an isotropic conductive foam using porous polyurethane foam includes forming polyurethane foam so as to mix open cells and closed cells by foaming polyurethane on the back surface of a release paper sheet (S310) A step S330 of coating a bonding adhesive on the back surface of the foam S320, a fabric layer of a woven polyester fabric so as to form a plurality of through holes in the bonding adhesive S330, removing the release paper, coating the skin layer A step S350 of forming an isotropic conductive foam by plating a multilayer formed in the step S340 by providing a plating liquid and a step S360 of laminating a conductive adhesive layer on the back surface of the isotropic conductive foam do.

In addition, it may further include a step of laminating the releasing paper to protect the adhesive surface of the stacked conductive adhesive layer in step S360.

4 is a view illustrating another method for producing an isotropic conductive foam using a porous polyurethane foam according to the present invention. The polyurethane foam is foamed on the back surface of the release paper to form a polyurethane foam so as to mix open cells and closed cells (S410) (S430) forming a skin layer on the back surface of the polyurethane foam, removing the release paper and coating the skin layer (S430), preparing a woven polyester fabric layer to form a plurality of through holes (S440), the polyurethane foam and the fabric layer are impregnated with a plating solution, plated and lapped to produce an isotropic conductive foam having conductivity (S450), and a step of laminating a conductive adhesive layer on the back surface of the isotropic conductive foam (S460).

In addition, it may further include a step of laminating the releasing paper to protect the adhesive surface of the stacked conductive adhesive layer in step S460.

Accordingly, the isotropic conductive foam using the porous polyurethane foam of the present invention is a thin-film urethane foam superior in shock absorbing power and restoring force as compared with the conventional conductive foam, and has an excellent isotropic conductivity by imparting electrical conductivity to the porous foam.

In addition, the present invention can be applied to a porous foam having a top-bottom energized structure by filling an open cell with a certain amount by impregnating a plating liquid containing a metal powder having electric charge, .

It is a microcellular conductive foam that has high isotropic electrical conductivity while maintaining excellent shock absorption and restitution of high density thin foams, thereby not only replacing the conductive foam of the conventional microcell sponge structure but also providing excellent shock absorption and heat conduction The heat diffusion function is excellent.

In addition, the present invention has the effect of satisfying the demand for miniaturization and weight reduction of a product as a material capable of simultaneously implementing shock absorption, light shielding, conductive and heat diffusion.

In addition, in the case of the foam and the fabric-bonded product of the prior art, the conductive foam of the present invention damages the appearance of the product due to the burr of the cut surface at the time of die-cutting, And a method for manufacturing a conductive foam which can solve the problem of causing a short circuit of the product and can be manufactured to a desired thickness without breaking the pore structure even when cut.

Hereinafter, the present invention will be described by way of examples, but the present invention is not limited thereto.

<Examples> Production of Isotropic Conductive Foam Using Porous Polyurethane Foam

Example 1

50 parts by weight of a polyether polyol resin, 50 parts by weight of a polyester polyol, 5 parts by weight of dipropylene glycol as a crosslinking agent, 2 parts by weight of nickel acetylacetone as a catalyst, 3 parts by weight of a silicone foam stabilizer as a catalyst, , 10 parts by weight of MDI (methylene diphenyl diisocyanate) as a curing agent, and 3 parts by weight of carbon black were mixed using a vacuum stirrer. After degassing treatment, 20 to 30% by volume of nitrogen gas was introduced into the mixture using a stirring / And then foamed on a PET film to prepare a porous polyurethane foam. The polyurethane foam was formed to have a thickness of 400 mu m. A bonding adhesive was coated on the back surface of the polyurethane foam, followed by laminating a fabric layer woven with polyester fibers. A plating solution containing copper was prepared and a laminated polyurethane foam-fabric layer was plated. A conductive adhesive layer prepared by using acrylic resin and copper powder on the back surface of the fabric layer was laminated. The conductive adhesive layer was cured by a thermal curing method and was made to have a thickness of 25 μm.

Example 2

A conductive foam was produced in the same manner as in Example 1, except that the polyurethane foam had a thickness of 10 mu m.

Example 3

A conductive foam was produced in the same manner as in Example 1, except that the polyurethane foam had a thickness of 3,000 mu m.

Example 4

A conductive foam was prepared in the same manner as in Example 1, except that the volume ratio of open cells to closed cells was changed by adding nitrogen gas at 30 to 40 volume%.

Example 5

A conductive foam was prepared in the same manner as in Example 1, except that the volume ratio of the open cell to the closed cell was changed by introducing nitrogen gas in an amount of 10 to 20% by volume.

Comparative Example 1

A conductive foam was produced in the same manner as in Example 1, except that the polyurethane foam had a thickness of 5 占 퐉.

Comparative Example 2

A conductive foam was produced in the same manner as in Example 1, except that the polyurethane foam had a thickness of 3,500 탆.

Comparative Example 3

A conductive foam was prepared in the same manner as in Example 1, except that the volume ratio of the open cell to the closed cell was changed by introducing nitrogen gas in an amount of 41 to 50% by volume.

Comparative Example 4

A conductive foam was prepared in the same manner as in Example 1, except that the volume ratio of the open cell to the closed cell was changed by adding nitrogen gas in an amount of 1 to 9% by volume.

Experimental Example

Experimental Example 1. Results of Resistance Test According to Thickness Change

The restorative force of the isotropic conductive foam using the porous polyurethane foam according to an embodiment of the present invention was tested.

The tape produced according to Examples 1 to 3 and Comparative Examples 1 and 2 was pressed through a press to test the restoring force thereafter. Here, restitution power was divided into ○ (good), △ (normal), and X (poor).

Thickness (㎛) Press force (N / m ² ) Psalter One 2 3 4 5 Example 1 400 196 O O O O O 490 O O O O O 588 O O O O O Example 2 10 196 O O O O O 490 O O O O O 588 O △ O △ O Example 3 3,000 196 O O O O O 490 O O O O O 588 △ O O △ O Comparative Example 1 5 196 △ △ △ △ △ 490 X △ X X X 588 X X X X X Comparative Example 2 3,500 196 O O O O O 490 O △ O O O 588 △ O △ △ △

Test results Referring to Table 1, the tapes of Examples 1 to 3 were found to have a much higher resilience than Comparative Examples 1 and 2. Comparative Example 1 having a polyurethane foam thickness of 5 탆 had a comparatively smaller restitution force than Example 1 and Comparative Example 2 having a surface roughness of 3,500 탆 showed a somewhat reduced restoring force as compared with Example 1, The thicker it is, the more the resilience is improved.

EXPERIMENTAL EXAMPLE 2 Closed-cell: Resilience test result according to volume change of open cell

The closed cell of the isotropic conductive foam using the porous polyurethane foam according to an embodiment of the present invention and the resilience according to the volume change of the open cell were tested. The tape produced according to Examples 1, 4 and 5 and Comparative Examples 3 and 4 was pressed through a press to test the restoring force thereafter. Here, restitution power was divided into ○ (good), △ (normal), and X (poor).

Closed cell: open cell ratio (volume%) Pressing force
(N / m ² ) Psalter One 2 3 4 5 Example 1 1: 1-2 196 O O O O O 490 O O O O O 588 O O △ O O Example 4 1: 2 ~ 3 196 O O O O O 490 O O O O O 588 O △ O △ △ Example 5 1: 0.1 to 1 196 O O O O O 490 O O O O O 588 △ O O O △ Comparative Example 3 1: 3.1 or higher 196 △ △ △ △ △ 490 X △ X X X 588 X X X X X Comparative Example 4 1: 0.001 to 0.09 196 O O O O O 490 O O O O O 588 O △ O O △

Test results Referring to Table 2, the tapes of Examples 1, 4 and 5 were found to have a very high restoring force compared to Comparative Example 3. Comparative Example 4 in which the volume percentages of the open cells and the closed cells are 1: 0.001 to 0.09 has similar resilience to that of Example 1, and Comparative Example 3 having a volume ratio of 1: 3.1 or more has relatively higher resilience And when the volume ratio of the open cell exceeds a certain ratio, it is difficult to obtain the restoration force due to the shock absorption effect of the closed cell, resulting in an economic loss.

Experimental Example 3: Closed-cell: Impact absorption test result according to volume change of open cell

A closed cell of an isotropic conductive foam using a porous polyurethane foam according to an embodiment of the present invention and a shock absorbing capacity according to a volume change of an open cell were tested.

Five specimens were prepared for each of the tapes prepared according to Examples 1, 4 and 5 and Comparative Examples 3 and 4, and were weighed using a ball drop tester using a weight of 55 g at a height of 500 mm After impacting the specimen, the impact buffer index of the specimen was measured by the impact energy.

Closed cell: open cell ratio (volume%) density
(g / cm ³ ) Psalter Face impact Face impact average Example 1 1: 1-2 0.48 One 53.96 54.95 2 52.36 3 56.65 4 58.80 5 53.08 Example 4
1: 2 ~ 3 0.38 One 38.51 36.85 2 37.03 3 37.11 4 36.15 5 35.45 Example 5
1: 0.1 to 1 0.58 One 66.18 67.91 2 69.03 3 69.55 4 68.26 5 67.55 Comparative Example 3 1: 3.1 or higher 0.29 One 17.05 17.12 2 16.95 3 17.39 4 17.28 5 16.94 Comparative Example 4 1: 0.001 to 0.09 0.67 One 29.01 29.11 2 28.95 3 29.39 4 29.27 5 28.94

Test results Referring to Table 3, the shock absorbing properties of Examples 1, 4 and 5 were superior to those of Comparative Examples 3 and 4, and the higher the volume ratio of the closed cells, the higher the shock absorbency.

Comparative Example 4 in which the volume% ratio of the open cell and the closed cell was 1: 0.001 to 0.09 showed a slight decrease in shock absorption as compared with Example 1, and Comparative Example 3 having a volume ratio of 1: It is found that when the volume ratio of the open cells exceeds a certain ratio, it is difficult to obtain the shock absorbing effect due to the closed cell, resulting in an economic loss.

EXPERIMENTAL EXAMPLE 4. Closed-cell: Compression force deflection (unit: Mpa) test result according to the volume change of the open cell

A closed cell of an isotropic conductive foam using a porous polyurethane foam according to an embodiment of the present invention and a shock absorbing capacity according to a volume change of an open cell were tested.

Five tapes prepared according to Examples 1, 4 and 5 and Comparative Examples 3 and 4 were prepared and compressed to 25% (Table 4) and 50% (Table 5) according to ASTM D3574 Standard Test Method The force repelled by the foam was measured.

Closed cell: open cell ratio (volume%) density
(g / cm ³ ) Psalter CFD (25%) CFD average value Example 1 1: 1-2 0.48 One 0.020 0.022 2 0.019 3 0.024 4 0.022 5 0.023 Example 4
1: 2 ~ 3 0.38 One 0.019 0.021 2 0.018 3 0.023 4 0.021 5 0.022 Example 5
1: 0.1 to 1 0.58 One 0.024 0.026 2 0.023 3 0.028 4 0.026 5 0.027 Comparative Example 3 1: 3.1 or higher 0.29 One 0.018 0.020 2 0.017 3 0.022 4 0.020 5 0.021 Comparative Example 4 1: 0.001 to 0.09 0.67 One 0.026 0.028 2 0.025 3 0.030 4 0.028 5 0.029

Closed cell: open cell ratio (volume%) density
(g / cm ³ ) Psalter CFD (50%) CFD average value Example 1 1: 1-2 0.48 One 0.060 0.062 2 0.059 3 0.064 4 0.062 5 0.063 Example 4
1: 2 ~ 3 0.38 One 0.052 0.054 2 0.051 3 0.056 4 0.054 5 0.055 Example 5
1: 0.1 to 1 0.58 One 0.085 0.087 2 0.084 3 0.089 4 0.087 5 0.088 Comparative Example 3 1: 3.1 or higher 0.29 One 0.038 0.040 2 0.037 3 0.052 4 0.050 5 0.051 Comparative Example 4 1: 0.001 to 0.09 0.67 One 0.096 0.098 2 0.095 3 0.100 4 0.098 5 0.099

Test results Referring to Tables 4 and 5, excellent CFDs were obtained in Examples 1, 4, and 5 as compared with Comparative Examples 3 and 4, and it was confirmed that the higher the volume ratio of the closed cells, the higher the CFD.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, It will be understood. It is therefore to be understood that the above-described embodiments are illustrative and not restrictive in every respect.

Accordingly, the spirit of the present invention should not be construed as being limited to the above-described embodiments, and all of the equivalents or equivalents of the claims, as well as the claims set forth below, belong to the scope of the present invention will be.

100: conductive foam 110: polyurethane foam
120: bonding adhesive 130: fabric layer
140: conductive adhesive layer 150: skin layer
160: release paper

Claims (11)

A polyurethane foam in which the volume ratio of the closed cell and the open cell is 1: 1 to 2;
A bonding adhesive coated on the lower part of the polyurethane foam;
A fabric layer of a woven polyester fabric so that a plurality of through holes adhered to the bonding adhesive are formed to have a size of 80 to 350 mesh;
A skin layer coated on at least one side of the polyurethane foam; And
And a conductive adhesive layer formed on one side of at least one of the fabric layer and the skin layer, the isotropic conductive foam comprising a porous polyurethane foam,
The volume ratio of the open cells to the closed cells of the polyurethane foam is preferably in the range
30 to 80 parts by weight of a polyether polyol, 30 to 80 parts by weight of a polyester polyol, 5 to 10 parts by weight of a crosslinking agent, 1 to 3 parts by weight of a catalyst, 1 to 5 parts by weight of a foaming agent, To 15 parts by weight of a black pigment and 1 to 5 parts by weight of a black pigment is degassed and nitrogen gas is introduced at a rate of 20 to 30 parts by volume per 100 parts by volume of the foaming composition to foam the mixture, ,
Wherein the polyurethane foam and the fabric layer comprise a plating layer partially filled with an open cell impregnated with a plating solution containing at least one or more metal powders of copper and nickel,
Wherein the electrically conductive pressure sensitive adhesive layer comprises a polymer resin containing a 2-ethylhexyl acrylate monomer, and comprises 3 to 20 parts by weight of a nickel metal powder having a size of 10 to 150 탆 based on 100 parts by weight of the pressure sensitive adhesive resin, Lt; RTI ID = 0.0 &gt; g / m. &Lt; / RTI &gt;
delete delete The method according to claim 1,
Wherein the fabric layer can be replaced with a thin film comprising at least one selected from the group consisting of aluminum, gold, silver, copper, nickel and carbon nanotubes.
delete delete delete delete (a) 30 to 80 parts by weight of a polyether polyol, 30 to 80 parts by weight of a polyester polyol, 5 to 10 parts by weight of a crosslinking agent, 1 to 3 parts by weight of a catalyst, 1 to 5 parts by weight of a foaming agent, , 5 to 15 parts by weight of a curing agent, and 1 to 5 parts by weight of a black pigment was subjected to defoaming treatment using a vacuum stirrer and nitrogen gas was introduced at a ratio of 20 to 30 parts by volume per 100 parts by volume of the foamable composition Forming a polyurethane foam such that the mixture of the closed cells and the open cells is mixed in a volume ratio of 1: 1 to 2;
(b) coating a bonding adhesive on the back surface of the polyurethane foam;
(c) laminating a woven polyester fabric layer so that a plurality of through holes adhered to the bonding adhesive are formed in a size of 80 to 350 mesh;
(d) removing the release paper and coating the skin layer;
(e) fabricating an isotropic conductive foam having conductivity that is partially filled with the plating liquid impregnated with a plating solution containing at least one of copper and nickel, which is electrically charged, and contains the metal powder; And
(f) 3 to 20 parts by weight of a nickel metal powder having a size of 10 to 150 탆, based on 100 parts by weight of the pressure-sensitive adhesive resin, of a polymer resin containing 2-ethylhexyl acrylate monomer on at least one surface of the isotropic conductive foam And a step of laminating a conductive adhesive layer on the conductive polyurethane foam.
(a) 30 to 80 parts by weight of a polyether polyol, 30 to 80 parts by weight of a polyester polyol, 5 to 10 parts by weight of a crosslinking agent, 1 to 3 parts by weight of a catalyst, 1 to 5 parts by weight of a foaming agent, , 5 to 15 parts by weight of a curing agent, and 1 to 5 parts by weight of a black pigment was subjected to defoaming treatment using a vacuum stirrer and nitrogen gas was introduced at a ratio of 20 to 30 parts by volume per 100 parts by volume of the foamable composition Forming a polyurethane foam such that the mixture of the closed cells and the open cells is mixed in a volume ratio of 1: 1 to 2;
(b) forming a skin layer on the back surface of the polyurethane foam;
(c) removing the release paper and coating the skin layer;
(d) preparing a fabric layer of a woven polyester fabric so that a plurality of through holes are formed in a size of 80 to 350 mesh;
(e) impregnating the polyurethane foam and the fabric layer with a plating liquid containing at least one or more metal powders of copper and nickel electrically charged to form a plated layer partially filled with the open cells, Preparing an isotropic conductive foil having an electrically conductive foam; And
(f) 3 to 20 parts by weight of a nickel metal powder having a size of 10 to 150 탆, based on 100 parts by weight of the pressure-sensitive adhesive resin, of a polymer resin containing 2-ethylhexyl acrylate monomer on at least one surface of the isotropic conductive foam And a step of laminating a conductive adhesive layer on the conductive polyurethane foam.
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