JP4122541B2

JP4122541B2 - Shield material

Info

Publication number: JP4122541B2
Application number: JP19672097A
Authority: JP
Inventors: 和男岩岡; 新一加藤; 文雄森中
Original assignee: Panasonic Corp; Matsushita Electric Industrial Co Ltd
Current assignee: Panasonic Corp; Panasonic Holdings Corp
Priority date: 1997-07-23
Filing date: 1997-07-23
Publication date: 2008-07-23
Anticipated expiration: 2017-07-23
Also published as: JPH1140980A

Description

【０００１】
【発明の属する技術分野】
本発明は電磁波ノイズ、静電ノイズを低減させるためのシ−ルド材に関するものである。
【０００２】
【従来の技術】
電気、電子回路から発生する不要な電磁波の放射防止、逆に電気、電子回路に侵入する不要な電磁波ノイズの低減や静電気による電子部品の破壊防止を目的とした対策のために従来より多くの電子部品やシ−ルド材が提案されてきた。
【０００３】
近年、電気、電子回路に使用される制御周波数が高周波に移行していることや制御方式がアナログ方式からデジタル方式になるに従って、電気、電子回路から放射される電磁波ノイズや、逆に外部から侵入する電磁波ノイズが問題になってきた。また、回路形成に使用される半導体部品では静電気による悪影響が問題となって来た。従来よりこれら電磁波ノイズや、静電気ノイズ防止対策として回路内部に抵抗器、コンデンサ、コイル等で構成されるノイズフィルタ−部品の使用や、ノイズを発生する電気、電子回路の部分を金属板で覆うことや、機器の筐体を金属製にしたり、筐体内部表面に金属層を形成したり、金属箔を必要部分に貼付して使用していた。又、金属箔のシ−ルド材としては圧延法や、電界法で製作された金属箔が多く使用されてきた。
【０００４】
【発明が解決しようとする課題】
これら電磁波ノイズや、静電気ノイズに影響されやすい精密な電気制御機器、携帯用機器、情報端末機が増加するに従ってこれらの機器より放射される電磁波や、これらの機器に侵入して機器の誤動作を誘発する電磁波や静電気ノイズが課題になってきた。特に携帯電話や携帯情報端末機は人体付近の使用が多く、使用周波数が高いことなどで漏洩電磁波が人体に与える影響が懸念されているとともに外部からのノイズの侵入による機器の誤動作を防止することが必要である。又、これらの携帯用機器はノイズの受発振防止とともに携帯機器の性格上小型、軽量化が望まれている。
【０００５】
本発明はこれらの点に鑑み、電磁波ノイズや、静電気ノイズの低減効果が優れ、かつ軽量なシ−ルド材を堤供するものである。
【０００６】
【課題を解決するための手段】
本発明は、電磁波ノイズの放射低減や、侵入低減、また静電気ノイズにより電子部品の破壊を防止するために使用されるシールド材で、真空蒸着法を用いて高分子フィルム上に電気伝導度の優れた銅（Ｃｕ）の金属膜層と、該銅（Ｃｕ）の金属膜層の変色や酸化を防止するために、該銅（Ｃｕ）の金属膜層の表面に耐侯性の良好なアルミニウム（Ａｌ）の金属膜層との２層の金属膜層を形成して全厚が薄く、軽く、しかもシールド効果の優れたシールド材とし、該シールド材を金属膜層の厚み対ノイズ低減効果をより効率的にするために２枚以上ラミネートした後にスルーホールを設け、該スルーホール内に導電性インクを充填し、シールド材の各々の金属膜層間を電気的に接続したシールド材としたもので、広範囲のシールドに対応できるようにしたものである。
【０００７】
【発明の実施の形態】
本発明は、電磁波、及び静電気をシ−ルドするシ−ルド材において、基板に高分子形成物よリ成る長尺のフィルムを用い、該フィルム表面上に真空中で金属膜の層を形成する方法を用いて製作することで不要な電磁波、及び静電気をシ−ルドする。
【０００８】
また、真空中で金属膜層を形成する方法が真空蒸着法であって１層目の金属膜層が銅（Ｃｕ），アルミニウム（Ａｌ），のいずれかであり２層目の金属膜層がスズ（Ｓｎ），ニッケル（Ｎｉ），クロム（Ｃｒ），チタン（Ｔｉ），アルミニウム（Ａｌ）のいずれかである、１層の金属膜層もしくわ２層の金属膜層で有ることを特徴とすることで、これらの第１層目の金属が電磁波、及び静電気のシ−ルドに有効であり、２層目の金属は１層目の金属の防錆に有効である。
【０００９】
さらに、高分子形成物よリ成る長尺のフィルム表面上に金属膜層を形成したシ−ルド材を接着剤を介して２枚以上ラミネ−トすることで、低減させようとする電磁波ノイズの周波数範囲が広くする。
【００１０】
さらに、ラミネ−トされた２枚以上のシ−ルド材の各々の金属膜層間を電気的に接続することで、中間層にラミネ−トされた金属膜層を表面層の金属膜層と導通させることやア−スに落とすこととなる。
【００１１】
【実施例】
本発明の詳細な内容を実施例を掲げて説明する。
【００１２】
図１に本発明シ−ルド材の製造方法例を示す。本発明シ−ルド材は真空蒸着法により高分子フィルム上に金属膜層を形成して成るもので、真空槽１を仕切板２にてフィルムの巻出し、巻き取り室３と蒸着室４に分離されている。巻出し、巻き取り室３と蒸着室４は各々真空排気管５及び、６にて必要な真空度に排気されるようにしてある。巻出し軸７から出た厚さ９μｍのポリエチレンテレフタレ−トフィルム８（以降ＰＥＴフィルム）は、フリ−ロ−ル９を経て蒸着用ドラム１０の外周面上を蒸着用ドラム１０と同期して一定の速度で走行させる。本実施例では２０ｍ／ｍｉｎの速度で走行させた。蒸着用ドラム１０の下部に対向させて蒸発金属１５を配置した。蒸発金属１５は耐熱性の高い材料から成るルツボ１４の内部に入れた後加熱源１６にて昇温、溶解、蒸発させる。蒸発原子１７はルツボ１４より蒸発してＰＥＴフィルム８の表面に付着、堆積することで金属膜層が形成される。本実施例では図示されていないが蒸発金属を昇温、溶解、蒸発過程では蒸着用ドラム１０と蒸発金属１５の間に遮蔽板を配置し、蒸発金属１５が充分に蒸発した後、遮蔽板を除くことで速度中のＰＥＴフィルム８の表面に金属膜層を形成した。金属膜層が形成され金属化された金属化フィルム１１はフリ−ロ−ル１２を経て巻き取り軸１３に巻き取られる。本実施例では上述した方法により１層目の金属膜層に銅（Ｃｕ）を厚さ１μｍに形成した後、２層目の金属層としてニッケル（Ｎｉ）を厚さ０．１μｍ形成した。尚、１層目の金属膜層及び、２層目の金属膜層の厚みはシ−ルド効果や真空蒸着法による金属膜層を形成する場合の効果を検討した結果、各々０．２〜２μｍ，０．０５〜０．２μｍの範囲が本発明を構成するのに最適であった。
【００１３】
図２に本発明シ−ルド材実施例１の断面構造図を示す。ＰＥＴフィルム８の表面上に真空蒸着法で銅（Ｃｕ）１８を厚さ１μｍに形成した。銅（Ｃｕ）１８層表面上の防錆剤１９は必要に応じて塗布塗布すればよい。本実施例は金属膜層が銅（Ｃｕ）１層タイプのシ−ルド材を示す。
【００１４】
図３に本発明シ−ルド材実施例２の断面構造図を示す。ＰＥＴフィルム８の表面上に同じく真空蒸着法で銅（Ｃｕ）１８を厚さ１μｍに形成した後、銅（Ｃｕ）１８の表面上に真空蒸着法でニッケル（Ｎｉ）２０を厚さ０．１μｍに形成した金属膜層が銅（Ｃｕ）１８、ニッケル（Ｎｉ）２０の２層タイプシ−ルド材の断面図を示す。１層目に銅（Ｃｕ）１８を使用することは良好な電気伝導度を求めたものであり、銅以外に銀（Ａｇ）が有効であった。また２層目の金属膜であるニッケル（Ｎｉ）２０は銅（Ｃｕ）１８層の防錆用としの金属膜層でありニッケル以外にスズ（Ｓｎ），クロム（Ｃｒ），チタン（Ｔｉ），アルミニウム（Ａｌ）の金属膜層が有効であった。
【００１５】
図４本発明の実施例３を示す。図３に示したＰＥＴフィルム８の表面上に銅（Ｃｕ）１８、ニッケル（Ｎｉ）２０の金属膜層を形成した２層タイプシ−ルド材を接着剤２４にてラミネ−トした後スル−ホ−ル２２を設け、該スル−ホ−ル内に導電性インク２３を充填して金属膜層１８、１８’及び、２０、２０’を電気的に接続したシ−ルド材を示す。このようなラミネ−トタイプのシ−ルド材はシ−ルド目的に合わせて必要枚数をラミネ−トしてシ−ルド材とすることで多くのシ−ルドに対応できる。
【００１６】
尚、本発明実施例では詳細を説明するために、具体的な材料や、寸法、形状、方法を記述したが本発明はこれらに限定されるものではない。
【００１７】
この様にして得られた本発明シ−ルド材のシ−ルド効果をタケダ理研法で測定した結果を表−１に示す。
【００１８】
【表１】

【００１９】
表−１に示された如く、１０、１００、３００ＭＨｚにおける電界シ−ルド効果は、従来より使用されている比較例に掲げたＰＥＴと銅箔をラミネ−トしたシ−ルド材と同等のシ−ルド効果を示した。又、磁界−ルドにおいては１０ＭＨｚでは導電体層の厚み効果により本発明は比較例に比べて効果は低いが周波数が３００ＭＨｚでは比較例に比べて本実施例は金属層の厚みが約２２％であるにもかかわらずシ−ルド効果は８．３％程度低いに過ぎなかった。さらに、実施例と比較例でのシ−ルド材での静電シ−ルド効果を測定したところ本実施例すべてのシ−ルド材で比較例と同様の効果があった。尚、１層目金属の防錆用として塗布した防錆剤や、２層目にニッケル（Ｎｉ）、錫（Ｓｎ），クロム（Ｃｒ），チタン（Ｔｉ），アルミニウム（Ａｌ）を形成したシ−ルド剤について、８５℃、６０％の恒温恒湿槽で１２時間放置試験を実施した。この結果１層のみの金属膜層で構成されたシ−ルド材に比較して防錆剤や防錆用に２層目を形成したシ−ルド材の１層目の変色や、腐食は大幅に少なかった。
【００２０】
【発明の効果】
この様に本発明により、下記の点において、効果をもたらした。
【００２１】
１、高分子フィルム・金属膜層の構成で全厚が薄く、しかも軽いシ−ルド材であリ、優れたシ−ルド効果が得られる。
【００２２】
２、製造工程が少なく、金属膜成膜が早い、等により低コストのシ−ルド材が提供できる。
【００２３】
３、フレキシビリティに富みシ−ルド材の加工性が高く多方面に使用できため、工業的価値が大である。
【図面の簡単な説明】
【図１】本発明における真空蒸着法による金属膜層の形成方法を示す図
【図２】本発明の実施例１の断面構成例を示す図
【図３】本発明の実施例２の断面構成例を示す図
【図４】本発明の実施例３の断面構成例を示す図
【符号の説明】
８：高分子フィルム
１１：金属化フィルム
１８：銅（Ｃｕ）金属膜層
２０：ニッケル（Ｎｉ）金属膜層[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a shield material for reducing electromagnetic noise and electrostatic noise.
[0002]
[Prior art]
More electrons than before to prevent radiation of unnecessary electromagnetic waves generated from electricity and electronic circuits, and to reduce unnecessary electromagnetic noise that enters electric and electronic circuits and to prevent destruction of electronic components due to static electricity Parts and shield materials have been proposed.
[0003]
In recent years, as the control frequency used for electric and electronic circuits has shifted to high frequencies and the control method has changed from analog to digital, electromagnetic noise radiated from the electric and electronic circuits and vice versa. EMI noise has become a problem. In addition, adverse effects due to static electricity have become a problem in semiconductor components used for circuit formation. Conventionally, as a countermeasure against electromagnetic wave noise and electrostatic noise, the use of noise filter parts composed of resistors, capacitors, coils, etc. in the circuit, and the parts of the electrical and electronic circuits that generate noise are covered with a metal plate. In addition, the casing of the device is made of metal, a metal layer is formed on the inner surface of the casing, or a metal foil is attached to a necessary part. Further, many metal foils manufactured by a rolling method or an electric field method have been used as a shielding material for metal foils.
[0004]
[Problems to be solved by the invention]
As the number of precision electrical control devices, portable devices, and information terminals that are susceptible to electromagnetic noise and electrostatic noise increases, electromagnetic waves radiated from these devices, and intrusion into these devices, causing malfunction of the devices Electromagnetic waves and static electricity noise that have become a problem. In particular, mobile phones and personal digital assistants are often used near the human body, and there are concerns about the effects of leaked electromagnetic waves on the human body due to the high frequency used, etc., and prevent device malfunction due to intrusion of external noise. is required. In addition, these portable devices are desired to be small and light in weight due to the characteristics of the portable devices while preventing noise reception and oscillation.
[0005]
In view of these points, the present invention provides a lightweight shield material that is excellent in the effect of reducing electromagnetic wave noise and electrostatic noise.
[0006]
[Means for Solving the Problems]
The present invention is a shielding material used to reduce electromagnetic noise emission, intrusion reduction, and prevent destruction of electronic components due to electrostatic noise , and has excellent electrical conductivity on a polymer film using a vacuum deposition method. the metal film layer of copper (Cu) were, in order to prevent discoloration and oxidation of the metal film layer of copper (Cu), the surface weather resistance of the high aluminum metal layer of the copper (Cu) (Al ) To form a two-layer metal film layer that is thin, light and excellent in shielding effect, and the shielding material is more efficient in reducing the thickness of the metal film layer against noise. In order to achieve this, a through hole is formed after laminating two or more sheets, a conductive ink is filled in the through hole, and a shield material in which each metal film layer of the shield material is electrically connected is used. It can correspond to the shield of Those were Unishi.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
According to the present invention, in a shield material that shields electromagnetic waves and static electricity, a long film made of a polymer forming material is used as a substrate, and a metal film layer is formed on the film surface in a vacuum. By manufacturing using the method, unnecessary electromagnetic waves and static electricity are shielded.
[0008]
Further, the method of forming the metal film layer in vacuum is a vacuum deposition method, the first metal film layer is either copper (Cu) or aluminum (Al), and the second metal film layer is It is characterized by having one metal film layer or two metal film layers of any one of tin (Sn), nickel (Ni), chromium (Cr), titanium (Ti), and aluminum (Al). Thus, these first layer metals are effective for shielding electromagnetic waves and static electricity, and the second layer metal is effective for rust prevention of the first layer metal.
[0009]
Furthermore, by laminating two or more shield materials having a metal film layer formed on the surface of a long film made of a polymer-formed material through an adhesive, the electromagnetic noise to be reduced is reduced. Increase the frequency range.
[0010]
Furthermore, the metal film layer laminated on the intermediate layer is electrically connected to the surface metal film layer by electrically connecting the metal film layers of each of the two or more laminated shield materials. Will be dropped or grounded.
[0011]
【Example】
The detailed contents of the present invention will be described with reference to examples.
[0012]
FIG. 1 shows an example of a method for producing the shield material of the present invention. The shield material of the present invention is formed by forming a metal film layer on a polymer film by a vacuum vapor deposition method. The vacuum chamber 1 is unwound by a partition plate 2 and is placed in a winding chamber 3 and a vapor deposition chamber 4. It is separated. The unwinding / winding chamber 3 and the vapor deposition chamber 4 are evacuated to a required degree of vacuum by vacuum exhaust pipes 5 and 6, respectively. A polyethylene terephthalate film 8 (hereinafter referred to as a PET film) having a thickness of 9 μm that has come out from the unwinding shaft 7 is fixed on the outer peripheral surface of the vapor deposition drum 10 through the free roll 9 in synchronization with the vapor deposition drum 10. Drive at a speed of. In this example, the vehicle was run at a speed of 20 m / min. The evaporation metal 15 was arranged facing the lower part of the evaporation drum 10. The evaporated metal 15 is put into the crucible 14 made of a material having high heat resistance, and then heated, melted and evaporated by the heating source 16. The evaporated atoms 17 evaporate from the crucible 14 and adhere to and deposit on the surface of the PET film 8 to form a metal film layer. Although not shown in the present embodiment, a shielding plate is disposed between the evaporation drum 10 and the evaporation metal 15 in the process of heating, melting and evaporating the evaporated metal, and after the evaporation metal 15 has sufficiently evaporated, the shielding plate is removed. By removing, a metal film layer was formed on the surface of the PET film 8 during the speed. The metallized film 11 formed with the metal film layer is wound around the winding shaft 13 via the free roll 12. In this example, copper (Cu) was formed to a thickness of 1 μm on the first metal film layer by the method described above, and then nickel (Ni) was formed to a thickness of 0.1 μm as the second metal layer. The thicknesses of the first metal film layer and the second metal film layer are 0.2 to 2 μm as a result of examining the effect of forming the metal film layer by the shield effect or vacuum deposition method. The range of 0.05 to 0.2 μm was optimal for constructing the present invention.
[0013]
FIG. 2 shows a sectional structural view of shield material embodiment 1 of the present invention. Copper (Cu) 18 was formed to a thickness of 1 μm on the surface of the PET film 8 by vacuum deposition. The antirust agent 19 on the surface of the copper (Cu) 18 layer may be applied and applied as necessary. This embodiment shows a shield material in which the metal film layer is a copper (Cu) single layer type.
[0014]
FIG. 3 shows a sectional structural view of shield material embodiment 2 of the present invention. Similarly, after forming copper (Cu) 18 to a thickness of 1 μm on the surface of the PET film 8 by vacuum evaporation, nickel (Ni) 20 is formed to a thickness of 0.1 μm on the surface of the copper (Cu) 18 by vacuum evaporation. FIG. 2 shows a cross-sectional view of a two-layer type shield material in which the formed metal film layer is copper (Cu) 18 and nickel (Ni) 20. The use of copper (Cu) 18 in the first layer was a good electrical conductivity, and silver (Ag) was effective in addition to copper. Further, nickel (Ni) 20 as the second metal film is a metal film layer for rust prevention of 18 layers of copper (Cu). Besides nickel, tin (Sn), chromium (Cr), titanium (Ti), A metal film layer of aluminum (Al) was effective.
[0015]
4 shows Embodiment 3 of the present invention. A two-layer type shield material in which a metal film layer of copper (Cu) 18 and nickel (Ni) 20 is formed on the surface of the PET film 8 shown in FIG. A shield material in which a conductive ink 23 is filled in the through hole 22 and the metal film layers 18, 18 ′ and 20, 20 ′ are electrically connected is shown. Such a laminated type shield material can be used for many shields by laminating a required number of sheets according to the purpose of the shield to obtain a shield material.
[0016]
In the embodiments of the present invention, specific materials, dimensions, shapes, and methods have been described in order to describe the details, but the present invention is not limited to these.
[0017]
The results of measuring the shield effect of the shield material of the present invention thus obtained by the Takeda RIKEN method are shown in Table 1.
[0018]
[Table 1]

[0019]
As shown in Table 1, the electric field shield effect at 10, 100, and 300 MHz is equivalent to that of a shield material obtained by laminating PET and copper foil, which has been used in comparative examples. -It showed the Ludo effect. In the magnetic field, the effect of the present invention is lower than that of the comparative example at 10 MHz due to the effect of the thickness of the conductor layer. However, at a frequency of 300 MHz, the thickness of the metal layer is about 22% as compared with the comparative example. Nevertheless, the shield effect was only as low as 8.3%. Furthermore, when the electrostatic shield effect in the shield material in the example and the comparative example was measured, the same effect as in the comparative example was obtained in all the shield materials in this example. It should be noted that the rust preventive agent applied for rust prevention of the first layer metal, and the second layer formed of nickel (Ni), tin (Sn), chromium (Cr), titanium (Ti), aluminum (Al). -About Ludo agent, the standing test was implemented in 85 degreeC and a 60% constant temperature and humidity tank for 12 hours. As a result, the discoloration and corrosion of the first layer of the rust preventive agent and the second layer for rust prevention are greatly reduced compared to the shield material composed of only one metal film layer. There were few.
[0020]
【The invention's effect】
As described above, the present invention has the following effects.
[0021]
1. The structure of the polymer film / metal film layer is thin and the shield material is light, and an excellent shield effect can be obtained.
[0022]
2. It is possible to provide a low-cost shield material due to a small number of manufacturing steps and quick metal film formation.
[0023]
3. The industrial value is great because it is highly flexible and the processability of shield material is high and can be used in many fields.
[Brief description of the drawings]
FIG. 1 is a diagram showing a method for forming a metal film layer by vacuum deposition in the present invention. FIG. 2 is a diagram showing a cross-sectional configuration example of Example 1 of the present invention. FIG. 3 is a cross-sectional configuration of Example 2 of the present invention. FIG. 4 is a diagram showing an example of a cross-sectional configuration of Example 3 of the present invention.
8: Polymer film 11: Metallized film 18: Copper (Cu) metal film layer 20: Nickel (Ni) metal film layer

Claims

In a shielding material that shields electromagnetic waves and static electricity, a metal film layer is formed using a method of forming a metal film layer in a vacuum on the film surface using a long film made of a polymer formed material on the substrate. After laminating two or more of the shield materials with an adhesive, a through hole is provided, and a conductive ink is filled in the through hole to electrically connect the metal film layers of the shield material. The metal film layer is composed of two layers, the first metal film layer is copper (Cu), and the second metal film layer formed on the surface of the first layer is aluminum. A shielding material characterized by being (Al) .

The thickness of the first copper (Cu) metal film layer is in the range of 0.2 to 2 (μm), and the thickness of the second aluminum (Al) metal film layer is 0.05 to 0.2 ( The shielding material according to claim 1, which is in a range of μm).