JP2015189094A - Electromagnetic wave shielding plate and manufacturing method of electromagnetic wave shielding plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electromagnetic wave shielding plate including an electromagnetic wave-shielding film in an assembled fiber state with a noise suppression function, having a rigid plate-like shape; and a manufacturing method of the electromagnetic wave shielding plate.SOLUTION: A laminate molding material 5 including an electromagnetic shielding film 100 held between a pair of molded original fabric materials 1 of fiber-reinforced resin composite material is disposed in a molding tool 9. The laminate molding material 5 includes an adhesion margin 1a which is not covered with the electromagnetic shielding film 100. A resin material 4 adhered to the molded original fabric material 1 is in a sticky adhesive-like semi-fluidized state before curing, and can be a commercially available prepreg sheet. The prepreg sheet is cured at 80°C. While the electromagnetic shielding film 100 typically melts at the temperature, the electromagnetic shielding film 100 held between the molded original fabric materials 1 can be cured in the molding tool 9 by heating and pressurizing.

Description

The present invention relates to an electromagnetic wave shielding plate obtained by laminating an electromagnetic shielding film having a noise suppressing function and a fiber reinforced resin composite, and a method for manufacturing the electromagnetic wave shielding plate.

Currently, mobile phones that are widely used in the world have an electromagnetic wave source with a predetermined frequency integrated with the mobile phone body. Therefore, as a result of using this in the vicinity of the temporal region, there is a concern about the influence on the user's brain and the surrounding human tissues and organs. In addition, there is a possibility of causing malfunction of a pacemaker or the like, and such problems that cannot be overlooked medically and problems of electromagnetic wave damage to an operator of a computer device or the like caused by electromagnetic waves transmitted from a CRT display have been pointed out (Patent Literature). 1).

Patent document 1 relates to such a problem, electromagnetic wave shielding sheet and film having a function of preventing the occurrence of various electromagnetic wave harmful effects and preventing the occurrence of various electromagnetic wave effects in advance, as well as properly blocking the irradiation of electromagnetic waves on various objects. And an electromagnetic shield.

Japanese Patent Laid-Open No. 10-259641

The electromagnetic wave shielding sheet, film, and electromagnetic wave shielding body having a static electricity generation preventing function shown in Patent Document 1 are thin and light sheets in a fiber assembly state, and for example, a shape necessary for forming a casing of an electronic device member Does not have retention.

The present invention has been made in view of the above problems in the prior art, and an object thereof is to provide an electromagnetic wave shielding plate having a rigid plate shape as an electromagnetic shielding film having a noise suppressing function in a fiber assembly state, and a method for producing the electromagnetic wave shielding plate. And

That is, the electromagnetic wave shielding plate of the present invention comprises an electromagnetic shielding film sandwiched between a pair of fiber reinforced resin composite materials, and each fiber reinforced resin composite material in a state in which the pair of fiber reinforced resin composite materials and the electromagnetic shielding film are laminated. An adhesive margin that is not covered with the electromagnetic shielding film is formed, and the opposing adhesive margins of the fiber reinforced resin composites are directly bonded to each other.

Since the electromagnetic wave shielding plate is formed by sandwiching an electromagnetic shielding film between a pair of fiber reinforced resin composite materials, rigidity, that is, shape retention is high, and surface design can be improved.

The fiber reinforced resin composite material is obtained by heat-curing a molding raw material of a fiber reinforced resin composite material obtained by impregnating a woven fabric base material containing a reinforcing fiber bundle with a resin material mainly composed of a thermosetting resin. can do.

Furthermore, the method for producing an electromagnetic wave shielding plate of the present invention comprises a step of sandwiching an electromagnetic shielding film between a pair of fiber reinforced resin composite molding raw materials and disposing the molding raw material in a molding die. And pressurizing surfaces are alternately provided in the upper mold direction and the lower mold direction in the circumferential direction centering on the pressing direction by the molding die.

According to the method for manufacturing an electromagnetic wave shielding plate of the present invention, since the pressing surface is alternately provided in the circumferential direction around the pressing direction in the upper mold direction and the lower mold direction of the molding die, It can be prevented that the mold adheres to the mold and is difficult to release, and the molded product can be easily released. Moreover, the burr can be easily removed from the mold to which the burr is attached.

Thus, by compression molding with a cross-beam structure, it is possible to prevent the occurrence of material displacement, which becomes a problem when molding with a normal molding die. In addition, a mold release mechanism is not required, and an unnecessary mold dividing line can be prevented from being transferred to the surface of the molded product, thereby improving the design.

The pressing surfaces can be extended alternately up and down to the edge of the mold. As a result, it is easy to remove burrs attached to the mold, and gas can be vented evenly from each side.

A pair of fibers is formed by forming an adhesive margin in which the electromagnetic shielding film is not laminated on the molding raw material of each fiber reinforced resin composite in a state in which the molding raw material of the pair of fiber reinforced resin composite and the electromagnetic shielding film are laminated. It is preferable to arrange the reinforced resin composite materials so that the bonding allowances face each other.

The forming raw material may be formed by impregnating a woven fabric base with a resin material containing a thermosetting resin as a main component.

Pre-heated laminated molding material with an electromagnetic shielding film sandwiched between a pair of molding raw materials that coincide in two orthogonal directions, and each of the two orthogonal directions of the bi-directional woven fabric is a square-cut die It is preferable to place them in the mold in a positional relationship orthogonal to the mold.

In such a method for producing an electromagnetic wave shielding plate of the present invention, the shape having a square-shaped standing wall is shaped so that the extending direction of the standing wall coincides with the orthogonal direction of the carbon fiber, thereby forming the rectangular shape. Even at the corners of the mold, the displacement of the weave of the bi-directional fabric was reduced to prevent an excessive decrease in strength.

Concavities and convexities may be provided on the pressing surface. Even in this case, by shaping the shape having a square-shaped standing wall so that the extending direction of the standing wall coincides with the orthogonal direction of the carbon fiber, the corners of the unevenness of the pressing surface provided with the unevenness In this case, the weave of the bi-directional fabric was reduced to prevent an excessive decrease in strength.

A metal plate may be sandwiched between a plurality of laminated molding materials in which an electromagnetic shielding film is sandwiched between a pair of molding raw materials in which two orthogonal directions coincide with each other, and placed in a molding die.

When an electromagnetic shielding film, that is, an electromagnetic shielding / absorbing film sheet, receives noise, it is consumed inside the sheet and has a high ability not to be reflected outside.
On the other hand, the carbon fiber reinforced resin composite is an electrical conductor, and when it receives noise, it reflects as it is and does not pass through the inside.
According to the electromagnetic wave shielding plate and the method for producing the electromagnetic wave shielding plate of the present invention, it is possible to further improve the performance as electromagnetic wave shielding by laminating the electromagnetic shielding film and the carbon fiber reinforced resin composite material. Become. Moreover, it can be expected that the added value of the product will be enhanced by the high design appearance of the carbon fiber reinforced resin composite material.

According to the electromagnetic wave shielding plate and the method for producing an electromagnetic wave shielding plate according to the present invention, an electromagnetic shielding film having a noise suppressing function in a fiber assembly state can be formed into a rigid plate shape.

The conceptual diagram of the electromagnetic wave shielding plate of one embodiment of this invention. (A) It is a conceptual diagram of the shaping | molding raw material used with the manufacturing method of the electromagnetic wave shielding board of this invention. (B) It is a conceptual diagram of the textile base material which comprises the shaping | molding raw material shown to Fig.1 (a). It is explanatory drawing of the shaping apparatus used with the manufacturing method of the electromagnetic wave shielding board of 1st embodiment of this invention. (A) It is a partial expansion perspective view of the shaping apparatus shown in FIG. (B) It is another partial expansion perspective view of the shaping apparatus shown in FIG. (A) FIG. 4 (a) is an IVa view. (B) FIG. 4 (b) is an IVb view. (A) It is a partial expansion perspective view of the other shaping apparatus used with the manufacturing method of the electromagnetic wave shielding board of 1st embodiment of this invention. (B) It is another partial expansion perspective view of the other shaping apparatus used with the manufacturing method of the electromagnetic wave shielding board of 1st embodiment of this invention. (A) FIG. 6 (a) is a view on arrow VIa. (B) FIG. 4 (b) is a view on arrow VIb. (A) It is an explanatory schematic diagram of the manufacturing method of the electromagnetic wave shielding plate of 2nd embodiment of this invention. (B) It is an explanatory schematic diagram regarding the manufacturing method of the electromagnetic wave shielding plate of 2nd embodiment of this invention. It is a description schematic diagram of the Example of this invention.

FIG. 1 is a conceptual schematic diagram of an electromagnetic wave shielding plate 101 according to an embodiment of the present invention.

The electromagnetic wave shielding plate 101 has an electromagnetic shielding film 100 sandwiched between a pair of fiber reinforced resin composites 1, and electromagnetic waves are applied to the fiber reinforced resin composites in a state where a pair of fiber reinforced resin composites and an electromagnetic shielding film are laminated. An adhesive margin 1a that is not covered by the shielding film is formed, and a bonding region I is formed by directly bonding the opposing adhesive margins of the respective fiber reinforced resin composite materials.

The electromagnetic wave shielding plate 1 is manufactured using a forming raw material 1 shown in FIG. As shown in FIG. 2 (a), the molding material 1 has a resin material 4 mainly composed of a thermosetting resin attached to at least one surface of a woven fabric base 3 including a plurality of reinforcing fiber bundles 2. Do it.

The woven fabric base 3 is a bi-directional woven fabric formed by weaving a plurality of reinforcing fiber bundles 2 aligned in one direction so as to be parallel to each other as shown in FIG. The bi-directional woven fabric has the advantage that it is easy to be deformed due to a change in the relative position between the reinforcing fiber bundles 2 and is easily deformed into a three-dimensional shape, and that it is easy to obtain a laminated molding material that is mechanically pseudo-isotropic with a small number of sheets. .

The reinforcing fiber bundle 2 may be a carbon fiber bundle, a graphite fiber bundle, a glass fiber bundle, an aramid fiber bundle, or the like, and is preferably a carbon fiber bundle. By using the carbon fiber bundle, the mechanical properties of the electromagnetic wave shielding plate as the final product can be improved.

The resin material 4 adhering to the surface of the woven fabric base 3 is mainly composed of a thermosetting resin capable of obtaining an action of bonding the layers of the woven fabric base 3.

As the thermosetting resin, an epoxy resin or other known materials can be appropriately applied.

A method for manufacturing the electromagnetic wave shielding plate according to the first embodiment of the present invention will be described in detail below with reference to FIG.

As shown in FIG. 3, a molding material 1 having a resin material 4 mainly composed of a thermosetting resin adhered to the surface of a woven fabric base 3 is used. First, a molding raw material 1 of a pair of fiber-reinforced resin composites is used. A step of placing the laminated molding material 5 sandwiching the electromagnetic shielding film 100 in the mold 9 is performed. An adhesive allowance 1 a that is not covered with the electromagnetic shielding film 100 is formed on the laminated molding material 5. The resin material 4 adhering to the molding material 1 is in a semi-fluid state with adhesive-like viscosity before the curing reaction, and a commercially available prepreg sheet can be used. Such a prepreg sheet is cured at 80 ° C., while the electromagnetic shielding film 100 usually melts the constituent film, but the electromagnetic shielding film 100 is sandwiched between the forming raw materials 1 in the molding die 9. Can be cured by heating and pressure.

At that time, the molding die 9 is heated in advance to raise the temperature of the molding raw material 1 sandwiching the electromagnetic shielding film 100, and the laminated molding material 5 is placed in the molding die 9. Next, the laminated molding material 5 is compressed. As a result, the thermosetting resin material 4 adhering to the fabric base material 3 is cured, and the layers of the laminated molding material 5 are bonded to each other, and the shape is maintained.

Thereafter, the mold 9 is cooled, the mold is opened, and the mold is released. Through the above steps, an electromagnetic wave shielding plate having high rigidity, that is, shape retention, obtained by sandwiching the electromagnetic shielding film 100 between a pair of fiber reinforced resin composite materials 5 using a thermosetting resin can be obtained.

As shown in FIGS. 4 and 5, the upper die 9a and the lower die 9b are alternately provided with pressing surfaces 91a and 91b in the circumferential direction around the pressing direction of the molding die 9 with respect to the laminated molding material 5, respectively. .

Thus, by heating the laminated molding material 5 to the curing temperature and then cooling it, it is possible to prevent the material from adhering to the molding die 9 and becoming difficult to release even if burrs are generated. Easy to release. Further, burrs can be easily removed from the mold 9 to which burrs have adhered.

In the embodiment in which the pressing surfaces 91a and 91b are alternately provided on the upper die 9a and the lower die 9b, as shown in FIGS. 6 and 7, the pressing surfaces 91a and 91b are alternately extended vertically to the mold edge. Can be. Thereby, the burr | flash adhering to the shaping | molding die 9 is easy to be removed, and it can degas from each side equally.

In the present embodiment, in the laminated molding material 5 in which the electromagnetic shielding film 100 is sandwiched between the molding raw materials 1, each molding raw material is in a state where a pair of the molding raw material 1 and the electromagnetic shielding film 100 are laminated. 1 is formed with an adhesive allowance 100a on which the electromagnetic shielding film 100 is not laminated, and the laminated forming material 5 is formed so that the adhesive allowances 100a of the pair of forming raw material materials 1 are opposed to each other.

By doing so, the laminated molding material 5 is placed in the mold 9 and compressed, whereby the thermosetting resin material 4 adhering to the fabric base material 3 is cured and the molding raw material of the laminated molding material 5 is obtained. The electromagnetic wave shielding plate 101 of the present invention is obtained by directly bonding the opposing materials 100a.

The obtained electromagnetic shielding plate 101 is not joined to the electromagnetic shielding film 100 and the forming raw material 1, and the electromagnetic shielding film 100 is held in a state of being sandwiched between the pair of forming raw materials 1.

Next, the manufacturing method of the electromagnetic shielding plate of 2nd embodiment of this invention is demonstrated.

In the manufacturing method of the electromagnetic wave shielding plate of the second embodiment, as shown in FIG. 8 (a), a plurality of laminated molding materials 5 each having the electromagnetic shielding film 100 sandwiched between the molding raw materials 1 are used. It differs from the manufacturing method of the electromagnetic wave shielding plate of 1st Embodiment-3rd Embodiment by the point which inserts and shape | molds the metal flake 102 between them.

In the method for manufacturing an electromagnetic wave shielding plate according to the second embodiment, a plurality of electromagnetic wave shielding plates 101 can be simultaneously formed using a plurality of laminated molding materials 5, and the production efficiency can be improved.

   As shown in FIGS. 4, 5 and 8A, the upper die 9a and the lower die 9b are alternately pressed in the circumferential direction around the pressurizing direction of the molding die 9 with respect to the laminated molding material 5 as a pressing surface 91a. And the manufacturing method of the electromagnetic shielding plate of this invention was implemented using the metal mold | die provided with 91b, and the electromagnetic shielding plate of this invention was manufactured. According to the mold shown in FIGS. 4, 5 and 8A, an ejector pin (projecting pin) 92 as provided in the mold 9 shown in FIG. 8B is not required. Also, the laminated molding material 5 can be put into the mold 9 directly on the mold surface while holding the material with both hands.

A thermosetting fiber reinforced resin composite material (Epoxy-CF3K) was used as a molding material, and a laminate with an electromagnetic shielding / absorbing film sheet was manufactured.
Three thermosetting Epoxy prepreg sheets were used as Epoxy-CF3K, and an electromagnetic shielding / absorbing film sheet as an electromagnetic shielding film 100 was sandwiched between the Epoxy prepreg sheets as shown in FIG. 9 (a).

Others were the same as in Example 1, and an electromagnetic shielding / absorbing film sheet as an electromagnetic shielding film 100 was sandwiched between two Epoxy prepreg sheets and one Epoxy prepreg sheet.

Others were carried out similarly to Example 1, and the electromagnetic shielding absorption Film sheet was pinched | interposed between two Epoxy prepreg sheets.

Other than in the first embodiment, a stainless steel plate is disposed between two laminated molded products 5 each having an electromagnetic shielding / absorbing film sheet sandwiched between two Epoxy prepreg sheets. At the same time, heating and pressing were performed.

For each of the above examples, production costs and molding cycles were evaluated. The production cost was 100 for Example 2, 82 for Example 3, and 63 for Example 4 when Example 1 was taken as 100. The molding cycle of Examples 1 to 3 is 18 minutes, whereas the molded product of Example 4 is 9 minutes, and Example 4 can be evaluated as a low-cost specification with the lowest production cost.

DESCRIPTION OF SYMBOLS 1 ... Molding raw material, 2 ... Reinforcement fiber bundle, 3 ... Textile base material, 4 ... Resin material, 5,14 ... Laminated molding material, 6 ... Preheating type, DESCRIPTION OF SYMBOLS 7 ... Near-infrared radiation | emission apparatus, 9 ... Mold, 91a, 91b ... Cut surface, 10 ... Product part type | mold, 11 ... Heat storage board, 13 ... Cooling water flow path, 12 ... Heater, 17 ... Lower mold, 17a ... Lower mold central block, 16 ... Upper mold, 16a ... Upper mold central block, 18 ... Counter mold, 19 ... concave type.

Claims (7)

An electromagnetic shielding film is sandwiched between a pair of fiber reinforced resin composites, and each fiber reinforced resin composite is not covered with an electromagnetic shielding film in a state where a pair of fiber reinforced resin composites and electromagnetic shielding films are laminated. An electromagnetic wave shielding plate, wherein the fiber-reinforced resin composite materials are bonded directly to each other with an opposing bonding margin.
The fiber reinforced resin composite material is obtained by heating and curing a molding raw material of a fiber reinforced resin composite material obtained by impregnating a woven fabric base material including a reinforcing fiber bundle with a resin material mainly composed of a thermosetting resin. 1. The electromagnetic wave shielding plate according to 1.
A step of sandwiching an electromagnetic shielding film between a pair of fiber reinforced resin composite molding raw materials, and placing the molding raw material in a mold; and pressing the molding raw material in the molding die. A method for producing an electromagnetic wave shielding plate, comprising: providing a pressing surface alternately in an upper die direction and a lower die direction in a circumferential direction centering on a pressing direction by a die.
A pair of fibers is formed by forming an adhesive margin in which the electromagnetic shielding film is not laminated on the molding raw material of each fiber reinforced resin composite in a state in which the molding raw material of the pair of fiber reinforced resin composite and the electromagnetic shielding film are laminated. The manufacturing method of the electromagnetic wave shielding board of Claim 3 arrange | positioned so that the adhesion allowance of each reinforced resin composite material may oppose.
The method for producing an electromagnetic wave shielding plate according to claim 4, wherein the forming raw material is obtained by impregnating a woven fabric base with a resin material containing a thermosetting resin as a main component.
Pre-heated laminated molding material with an electromagnetic shielding film sandwiched between a pair of molding raw materials that coincide in two orthogonal directions, and each of the two orthogonal directions of the bi-directional woven fabric is a square-cut die The method for producing an electromagnetic wave shielding plate according to any one of claims 3 to 5, wherein the electromagnetic wave shielding plate is placed and placed in a molding die in a positional relationship orthogonal to each other.
The electromagnetic wave shielding according to claim 5 or 6, wherein a metal plate is sandwiched between a plurality of laminated molding materials in which an electromagnetic shielding film is sandwiched between a pair of molding raw materials whose two orthogonal directions coincide with each other, and placed in a molding die. A manufacturing method of a board.

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