KR20100027730A - A conductive cushion sheet and manufacturing method the same - Google Patents

Abstract

PURPOSE: A conductive cushion sheet and a method of manufacturing thereof are provided to insure excellent conductivity in both horizontal and vertical directions by plating a metal thin film layer on the surface and on the inside of a foaming foam. CONSTITUTION: A conductive cushion sheet comprises a polymer foaming foam, which is permeable vertically and horizontally with a density ranging from 40~400kg/cubic meters, to be used as a cushion material. The foaming foam is processed through electroless plating to improve horizontal and perpendicular conducting. The foaming foam has a sealing ability by applying conductivity to the surface and the inside of the foaming foam. The foaming foam is composed with a material selected from a group consisting of an acrylic resin, a urethane resin, a silicon resin, an epoxy resin, polyurethane, polyethylene, polypropylene, polyethylene terephthalate, or a synthetic rubber. The thickness of the polymer foaming foam is 0.01~15.0 millimeters.

Description

A conductive cushion sheet and manufacturing method the same

The present invention relates to a conductive cushion sheet excellent in electrical conductivity and a method of manufacturing the same, and more particularly to nickel, copper, gold, silver, and tin having excellent conductivity on the inside and the surface of a foam having air permeability in a thickness direction and a planar direction. The present invention relates to a conductive cushion sheet capable of conducting electricity up and down without drilling or cutting through upper and lower portions by imparting conductivity by electroless plating of a metal such as cobalt.

Harmful electromagnetic waves generated on the circuits of various electronic devices are inferior in some cases, impairing the propagation of the surrounding parts or the function of parts, degrading performance, damaging noise and images, shortening the lifespan, Cause generation.

In addition, as the electronic equipment has been improved in performance and miniaturization, many circuits have been integrated in a narrow space, and electromagnetic waves have leaked from the joints of the electronic devices or the opening and closing doors, thereby adversely affecting the electronic equipment and the human body.

As a result, a conductive gasket is used to shield the leaked electromagnetic wave, and the conductive gasket has a shock absorbing function and a sealing function that is completely in close contact with a gap to protect the electronic device from impact, and in the electronic device. There is a need for an electromagnetic shielding function for shielding generated electromagnetic waves. In particular, with respect to the electromagnetic shielding function of the conductive gasket, it should be electrically conductive in the horizontal direction of the gasket, and good conductivity in the vertical direction of the gasket.

Various electromagnetic and electromagnetic wave blocking materials have been developed to block electromagnetic waves or electromagnetic waves.A method of imparting electrical conductivity to a cushioning material that absorbs shock includes conductive materials such as polymer resin, plastic, rubber, foam, and the like. There is a method of mixing and dispersing inside and sticking or laminating a highly conductive material to the polymer surface. Recently, the cushion material made of a polymer elastomer resin is perforated to penetrate in the thickness direction, and the surface portion of the cushion material and the inner wall are perforated. A method of producing a conductive sheet for blocking electromagnetic waves by electroless plating, coating, and depositing a conductive material on the substrate has been proposed.

However, the technique of dispersing the conductive material inside the polymer should have a high filling rate of the conductive material in order to exhibit high conductivity, but in this case, the cushioning force of the conductive sheet is significantly lowered. Shielding performance is poor.

In addition, the technique of embedding the conductive material in the polymer matrix is limited in thickness when the mesh, the metal foil, the mesh plate, etc. are embedded, the conductivity varies depending on the density of the mesh state, and the density is high to obtain sufficient conductivity. In the case of facilitation, there is a problem that the buffering force of the conductive sheet is remarkably inferior.

In addition, the technique of sticking and laminating a highly conductive material to a polymer surface results in loss of elasticity on the surface of the conductive seek or adhesion when the metal mesh and the like are adhered and laminated, thereby degrading the performance of preventing electromagnetic leakage of electronic devices.

In addition, the technique of perforating the cushion material made of a polymer elastomer resin in the thickness direction so as to electrolessly plate, coat, and deposit a conductive material on the surface portion of the cushion material and the inner wall of the perforated material is perforated and cut through the upper and lower portions of the cushion material. The production cost is increased in the production of conductive sheets because additional processes such as these are required, and the sheet is ruptured during the processes such as drilling and cutting, which is not suitable for the production of continuous processes. The conductive sheet, which has undergone the process of having a relatively reduced surface area, has poor adhesion and physical strength on the surface, and thus, electromagnetic wave shielding effect is also reduced.

In addition, when the thickness of the sheet is 1.0 mm or more, there are limitations in the drilling and cutting processes, and there is a disadvantage in that a conductive sheet having a thickness of 1.0 mm or more cannot be manufactured.

Therefore, the present invention has been made to solve the above problems, the main object of the present invention is excellent in horizontal and vertical energization without further processing such as perforation or cutting of the sheet, and is limited in the thickness of the sheet It is to provide a conductive cushion sheet without.

In order to achieve the above object, the present invention uses a polymer foam having a breathability in a thickness direction and a planar direction having a density in the range of 40 ~ 400 kg / ㎥ as a cushioning material, electroless plating the surface and the inside of the foam Thus, it provides a conductive cushion sheet with excellent sealing and excellent horizontal and vertical energization.

In addition, the present invention provides a conductive cushion sheet for electromagnetic shielding laminated on one or both surfaces of the conductive cushion sheet for use in using a conductive adhesive layer, a conductive hot melt layer, a conductive coating layer, a conductive fiber layer, a metal foil layer.

The present invention also provides a method for producing a conductive cushion sheet for shielding electromagnetic waves excellent in electrical conductivity.

In the conductive cushion sheet according to the present invention, since foam foam having its own breathable structure is used as a cushioning material without undergoing additional processes such as perforation and cutting in the thickness direction of the cushioning material, when electroless plating the foam foam, The plating of the metal thin layer to the inside of the surface as well as the inside can exhibit excellent conductivity in the horizontal and vertical directions, and it is possible to preserve the physical properties of the foam foam as it is not processed, such as drilling and cutting.

In addition, the conductive cushion sheet of the present invention is excellent in electromagnetic shielding, elasticity, shock absorption and sealing properties to absorb external shock and internal vibration generated in devices such as electronic communication devices, portable mobile devices, plasma display panels, liquid crystal display devices, etc. Electromagnetic shielding by shock absorbers or excellent conductivity, and can be usefully used as a gasket sheet for shielding electromagnetic waves.

Hereinafter, the present invention will be described in detail.

The present invention provides an electrically conductive cushion sheet excellent in electrical conductivity and a method of manufacturing the same.

Specifically, the present invention uses a polymer foam having a breathability in the thickness direction and a planar direction in the range of 40 ~ 400 ㎏ / ㎥ density as a cushioning material and electroless plating the foam foam electroconductive on the surface and inside of the foam foam By providing this, a conductive cushion sheet excellent in hermeticity and horizontal and vertical energization is provided.

In the present invention, the polymer foam is acrylic resin, urethane resin, silicone resin, acrylic resin, epoxy resin, polyurethane (PU), polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), synthetic It is characterized by using foamed foams having air permeability in the horizontal and vertical directions by foaming foamed sheets charged, electrically conductive, flame retardant, and non-flammable, such as rubber. At this time, the thickness of the foam is preferably in the range of 0.01 to 15.0 mm, more preferably in the range of 0.1 to 5.0 mm.

In addition, the electroless plating is characterized in that a metal thin film layer is formed on the surface and the inside of the foam after a non-ferrous metal material such as copper, nickel, silver, gold, aluminum through a washing process, an etching process, a catalytic process, etc. In addition to the above, in order to correct the tensile strength of the foam foam or fiber or polymer film on one or both sides of the foam, preferably woven fabric, non-woven fabric, such as mesh or PE, PP, PET, polyethylene or Polymer films such as phthalate (PEN) and imide may be bonded to each other to perform electroless plating.

In addition, the present invention provides a conductive cushion sheet for electromagnetic shielding laminated on one or both surfaces of the conductive cushion sheet for use in using a conductive adhesive layer, a conductive hot melt layer, a conductive coating layer, a conductive fiber layer, a metal foil layer.

The conductive adhesive layer may be prepared by coating a plated fabric, a nonwoven fabric, a fiber, a metal foil, or the like as a support to one or both surfaces of the support at a predetermined thickness, preferably 3 to 100 μm, and the conductive As the hot melt layer, a hot melt adhesive based on a main base such as urethane, polyester, nylon, and ethylene vinyl acetate having a melting point of 50 to 300 ° C. may be used.

In addition, the conductive coating layer is prepared by adding conductive powders such as copper, nickel, silver gold, carbon black, graphite, etc. to urethane, acrylic, silicone, polyester, epoxy resin having excellent elasticity, roll coating, casting, screen printing, Coating may be performed by spraying, gravure coating, or the like.

In addition, the conductive fiber layer may impart conductivity by electroless plating of fibers such as woven fabrics, nonwoven fabrics, and meshes, and the metal foil layer may use a metal foil having conductivity such as aluminum, copper, nickel, and tin.

In the present invention, the electromagnetic shielding conductive cushion sheet is characterized in that the conductive cushion sheet is configured by stacking a single layer or two or more.

The present invention also provides a method for producing a conductive cushion sheet for shielding electromagnetic waves excellent in electrical conductivity.

Specifically, the present invention

(1) using a polymer foam having air permeability in the thickness direction and the planar direction in the range of density 40 ~ 400 ㎏ / ㎥ as a cushioning material, by electroless plating the foam foam to form a metal thin film layer on and inside the foam foam To impart electrical conductivity; And

(2) laminating to one or both sides of the cushioning material according to the use of a conductive adhesive layer, a conductive hot melt layer, a conductive coating layer, a conductive fiber layer, a metal foil layer, etc .; It provides a method of manufacturing.

Hereinafter, the present invention will be described in more detail with reference to Examples.

However, the following examples are merely to illustrate the invention, but the content of the present invention is not limited to the following examples.

Example 1.

Density is 40 ~ 400 ㎏ / ㎥, using a 0.5 mm thick polyurethane foam having a breathability in the thickness direction and planar direction as a cushioning material, and electroconductive to the surface and interior of the foam foam through electroless plating A cushion sheet was prepared.

By measuring the horizontal resistance, vertical resistance, shielding effect, etc. of the prepared conductive cushion sheet to confirm the performance as a conductive cushion sheet for electromagnetic shielding, the results are specified in Table 1 below.

Comparative Example 1.

Density is 40 ~ 400 ㎏ / ㎥, using 0.5 mm thick polyurethane foam with no breathability in the thickness direction and planar direction as a cushioning material, and by applying electroless plating to the surface and inside of the foam foam and conductive A cushion sheet was prepared.

Horizontal resistance, vertical resistance, shielding effect, etc. of the prepared conductive cushion sheet were measured, and the results are shown in Table 1 below.

Comparative Example 2.

The cushion foam is made of a polyurethane foam having air permeability in the thickness direction and the planar direction used in Example 1, perforated in the thickness direction (0.3 mm in diameter and 1.0 mm in the space of the cloth), and then electroless plating is performed to conduct the conductive cushion sheet. Was prepared.

Comparative Example 3.

A cushioning material made of polyurethane foam having no air permeability in the thickness direction and the planar direction used in Comparative Example 1, perforated in the thickness direction (0.3 mm in diameter and 1.0 mm distance in the cloth space), and then electroless plating was performed to conduct conductive cushion sheet. Was prepared.

Comparison of Properties of Conductive Cushion Sheets Example 1 Comparative Example 1 Comparative Example 2 Comparative Example 3 Horizontal resistance 0.03 0.03 0.03 0.03 Vertical resistance 0.03 ∞ 0.08 0.08 Shielding effect (dB) 94 92 85 82 Compression Strain (%) 5 or less below 10 5 or less below 10 Tensile Strength (㎏f / ㎠) 0.03 0.01 0.3 0.01 % Elongation 50 or less 100 or more 100 or more 100 or more

From the above results, the conductive cushion sheet according to the present invention uses a foam having its own breathable tissue structure, and since the foam is electroless plated, a metal thin film layer is plated and perforated as well as the surface of the foam. It was confirmed that excellent conductivity was exhibited in the horizontal and vertical directions without a process such as an incision.

1 is a cross-sectional view of a foam according to an embodiment of the present invention.

2 is a cross-sectional view of a thermal compression foam according to an embodiment of the present invention.

** Explanation of symbols on the main parts of the drawing **

1: breathable structure by continuous connection in foam

2: breathable foam foam with electroconductive plating on the surface and inside

Claims (13)

The airtightness and horizontality is achieved by using a polymer foam having air permeability in the thickness direction and a planar direction in the range of 40 to 400 ㎏ / ㎥ as a cushioning material and electroless plating the foam to impart conductivity to the surface and inside of the foam. , Conductive cushion seat with excellent vertical conduction. The method of claim 1, The polymer foam is selected from acrylic resin, urethane resin, silicone resin, acrylic resin, epoxy resin, polyurethane (PU), polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), or synthetic rubber Conductive cushion sheet, characterized in that at least one kind. The method according to claim 1 or 2, The conductive foam sheet, characterized in that the thickness of the polymer foam is in the range 0.01 ~ 15.0 mm. The method of claim 1, The electroless plating may be performed by washing at least one non-ferrous metal material selected from copper, nickel, silver, gold, or aluminum through a washing process, an etching process, and a catalytic process to form a metal thin film layer on the surface and inside of the polymer foam. A conductive cushion sheet, characterized in that. The method of claim 4, wherein In addition to the above, in order to correct the tensile strength of the foam foam conductive cushioning sheet characterized in that the electroless plating by bonding a fiber or polymer film to one or both sides of the foam. A conductive cushion sheet for electromagnetic shielding having excellent electrical conductivity by laminating one or more selected from a conductive adhesive layer, a conductive hot melt layer, a conductive coating layer, a conductive fiber layer, or a metal foil layer on one or both surfaces of the conductive cushion sheet of claim 1. The method of claim 6, The conductive pressure-sensitive adhesive layer is a conductive cushion sheet for electromagnetic shielding, characterized in that the fiber or metal foil as a support by applying a thickness of 3 ~ 100 ㎛ on one or both sides of the support. The method of claim 6, The conductive hot melt layer is a conductive cushion sheet for electromagnetic shielding, characterized in that using at least one hot melt adhesive selected from urethane, polyester, nylon, or ethylene vinyl acetate having a melting point of 50 ~ 300 ℃. The method of claim 6, The conductive coating layer is a roll coating, casting, screen printing, spray, by adding at least one conductive powder selected from copper, nickel, silver gold, carbon black, or graphite to urethane, acrylic, silicone, polyester, or epoxy resin Electromagnetic shielding conductive cushion sheet, characterized in that the coating by any one method of gravure coating. The method of claim 6, The conductive fiber layer is an electromagnetic shielding conductive cushion sheet, characterized in that to impart conductivity by electroless plating one or more fibers selected from woven, non-woven, or mesh. The method of claim 6, The metal foil layer is a conductive cushion sheet for electromagnetic shielding, characterized in that using a metal foil having at least one conductivity selected from aluminum, copper, nickel, or tin. The method of claim 6, A conductive cushion sheet for electromagnetic shielding, characterized in that the conductive cushion sheet is formed by laminating a single layer or two or more layers. (1) using a polymer foam having air permeability in the thickness direction and the planar direction in the range of density 40 ~ 400 ㎏ / ㎥ as a cushioning material, by electroless plating the foam foam to form a metal thin film layer on and inside the foam foam To impart electrical conductivity; And (2) laminating any one or more selected from conductive adhesive layers, conductive hot melt layers, conductive coating layers, conductive fiber layers, or metal foil layers on one or both surfaces of the cushioning material; Method for producing a conductive cushion sheet.

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